Glass - Science topic

It won't make a difference.

The problem with PDMS is, that it keeps changing its surface, through internal rearranging of bonds. That's why you loose hydrophilicity after a couple of hours (that and through airborne hydrocarbon contaminants). Depositing SiO2 on PDMS is possible but the adhesion is bad. There is no affinity of the polar SiO2 to the non-polar PDMS. It might work if you first treat the PDM with oxygen plasma to create OH-groups on the PDMS surface, immediately followed by SiO2 deposition so that you get a chemical bond through the OH groups, which then will be more difficult to rearrange internally, since they are stuck to the SiO2 layer.

Your images do not include the x-axis. You do not mention the radiation, nor the diffractometer type used for the experiment. Without this absolutely necessary information, which needs to always be included with any kind of powder diffraction measurement, no help is possible.

Dear Paul Thomas ,

That is great. TEOS tends to be reactive, due to the presence of Si-O-C2H5 groups, either in the presence of acids or bases. There are some examples here:

It is advised to be careful when using it since it "likes" water for example. It is not dangerous at all, but you should not leave bottles open or something similar since it will start reacting with the ambient moisture for example.

Best of luck with your research!

Alan F Rawle Hi Alan, thank you for your advice. I will try to eliminate moisture as much as possible to see how it performs.

Dabin

If you are dealing with cells Glass bottom 96 well plate for microscopy is your best fried such as those: https://www.cellvis.com/_96-well-glass-bottom-plates_/products_by_category.php?cat_id=11

You can culture, fix, incubate and wash in the same plate and use PBS instead of mounting media.

If your specimens are actual tissue sections you can keep them wet with PBS using a pap pen but I'm not sure it would be significantly less labor than cover slipping the sections.

How do you collected XRD patterns? Grazing angle or normal configuration? Do you expect to have crystalline materials after your thermal treatment? Is it possible that amorphous phases form?

Hi, I have more to add on this question, how can we prepare such transwell inserts for histology, the ones I am using have an area for 0.3 cm2 ....

Kaushik Shandilya's analysis is accurate; the FTIR peaks at 2925 cm⁻¹ and 1745 cm⁻¹ in the glass spectrum correspond to C-H and C=O bonds. Pinkie Jacob Eravuchira, please find below some references to relevant papers.

'Morning Martha,

I should have added a little footnote - depending on the camera, another approach is to pot the camera but to leave the window/lens free.

Reason being, if you pot the lens as well, you've then got to;

a) cast a flat surface (not hard, but...)

b) account for the distortion of having a 1.45 index material - of differing thickness - infront of the lens.

I'd be inclined to pot the electronics, paint the epoxy up to the edge of the window/lens, and no further.

Might need some preparation of the lens/window - but that depends on the nature of the materials.

Can you share a pic/diagram of the camera itself?

I would consider cognitive-motor dual-tasks, while not the same visual knockdown can at least disrupt attentional compensation for motor control

May consider using Permai fluorescence dye.

Effect of Short Glass Fiber Addition on Flexural and Impact Behavior of 3D Printed Polymer Composites

Cite this: ACS Omega 2023, 8, 10, 9212–9220

Publication Date:March 1, 2023

Copyright © 2023 The Authors. Published by American Chemical Society. This publication is licensed under

CC-BY-NC-ND 4.0.

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Abstract

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Fused deposition modeling (FDM), one of the most widely used additive manufacturing (AM) processes, is used for fabrication of 3D models from computer-aided design data using various materials for a wide scope of applications. The principle of FDM or, in general, AM plays an important role in minimizing the ill effects of manufacturing on the environment. Among the various available reinforcements, short glass fiber (SGF), one of the strong reinforcement materials available, is used as a reinforcement in the acrylonitrile butadiene styrene (ABS) matrix. At the outset, very limited research has been carried out till date in the analysis of the impact and flexural strength of the SGF-reinforced ABS polymer composite developed by the FDM process. In this regard, the present research investigates the impact and flexural strength of SGF–ABS polymer composites by the addition of 15 and 30 wt % SGF to ABS. The tests were conducted as per ASTM standards. Increments in flexural and impact properties were observed with the addition of SGF to ABS. The increment of 42% in impact strength was noted for the addition of 15 wt % SGF and 54% increase with the addition of 30 wt % SGF. On similar lines, flexural properties also showed improved values of 44 and 59% for the addition of 15 and 30 wt % SGF to ABS. SGF addition greatly enhanced the properties of flexural and impact strength and has paved the path for the exploration of varied values of reinforcement into the matrix.

This publication is licensed under

CC-BY-NC-ND 4.0.

1. Introduction

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3D printing, also known as additive manufacturing (AM), according to ISO/ASTM 52900:2015, is defined precisely as a fabrication process used for the creation of 3D models by assimilating the material layer by layer taken from the data developed by the 3D model software. (1) The 3D model is extracted from the computer-aided design software. (2) Utilizing the methodology of AM helps in the development of lightweight and complex parts, the manufacture of which is difficult by conventional methods of manufacturing. (3,4) One of the most widely used technologies presently of AM is based on extrusion technology, known as fused deposition modeling (FDM). The utilization of this technology is gaining popularity due to commercial and sustainable advantages, such as optimized material utilization, better energy efficiency, development of any complex geometry, and enhanced life cycle of the fabricated products. (5) The process of FDM works by feeding the filament into the nozzle; the filament melts in the heating chamber before entering the nozzle. The nozzle deposits the material layer by layer on the print bed, which is controlled by a numerical control program. (6) The material deposition takes place until the complete model is built.

The majority of FDM materials are thermoplastics, including polycarbonate, polylactic acid, and acrylonitrile butadiene styrene (ABS). These thermoplastics provide low stiffness and strength to the fabricated parts, leading to their use as prototypes as opposed to functional materials. (7) Numerous researchers have attempted to improve the properties of thermoplastics by incorporating various reinforcements. The most prevalent reinforcements are fibers, tubes, powder, and nanoparticles. (8) Studies by Caminero (9) revealed that reinforcement improved the mechanical properties compared to unreinforced materials. Recent research has centered on the addition of short fibers or continuous fibers (CFs) to thermoplastic materials, which has been shown to improve their mechanical properties. (10,11) In contrast to the addition of long fibers as reinforcement, the utilization of short fibers plays a significant role in filament development in terms of economic benefit and practicability. Numerous studies have been conducted on the utilization of short fibers as reinforcement in filament development. Caminero et al. (12) have demonstrated the viability of developing a graphene-reinforced polylactic acid polymer composite filament, which is then evaluated for the mechanical, dimensional, and surface roughness properties of 3D-printed composites. Tambrallimath et al. (13) demonstrated the successful synthesis and characterization of a graphene-reinforced polycarbonate (PC)–ABS polymer composite extracted as a filament for fused deposition modeling. Surface roughness and dimensional accuracy measurements were superior for PC–ABS with additives. By combining short glass fibers (SGFs) with the ABS polymer, Zhong et al. (14) created a novel composite material. It was observed that the addition of SGFs increased the tensile strength and surface rigidity. This study led to the significant conclusion that the addition of a plasticizer or the optimal amount of glass fiber increased the composite’s toughness. Tekinalp et al. (15) measured the tensile testing of 3D-printed CF/ABS polymer composites with fiber content ranging from 10 to 40% by weight. Fragmented specimens suggested an increase in internal porosity due to an increase in fiber content. With increased fiber content, however, Young’s modulus and tensile strength values increased. It was discovered that fiber orientation was a significant factor in determining the properties of 3D-printed components. In a similar study of CF addition to ABS conducted by Ning et al., (16) the fiber length increment increased the tensile strength.

Tian et al. (17) discovered that at higher temperatures, the surface accuracy of continuous carbon fiber reinforced in PLA would decrease. Increasing the temperature to extremely high levels during printing will result in the formation of pores on the inner surface of the printed part, thereby diminishing its strength. (18) According to Nazan et al., (19) warping is observed at very high printing temperatures due to high nozzle temperatures. Based on these temperature-related studies, the optimal printing temperature should be set so that the material can flow and fuse, rather than completely melt.

Tambrallimath et al. (20) reported that the addition of carbon nanotubes to a PC–ABS matrix resulted in an increase in tensile and impact strength. Experimentally analyzing the flexural behavior and impact strength of SGF-reinforced PLA composites is the focus of the current study, which investigates the wide range of research conducted on fiber-reinforced polymer composites developed via FDM.

As there are currently very few relevant studies on the addition of SGFs as reinforcement and the amount of fiber to be used as reinforcement, the experimental study focused on the development of 1.75 mm filaments with 15 and 30 wt % SGF added to PLA. Flexural and impact specimens were manufactured in accordance with ASTM standards. For fabrication, the optimal printing process parameters were selected, and property studies with build direction, infill density, and orientation were prioritized. This would greatly facilitate the printing process and make possible outcomes clear. Authors were able to examine the dispersion characteristics of SGFs in polymer matrices using scanning electron microscopy (SEM). Microstructure analyses of FDM-printed parts provide greater insight into the structure of specimens. This would aid numerous researchers in the development of new models by serving as a reference study.

2. Materials and Methods

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2.1. Raw Materials

Pellets of ABS procured from M/s (Messrs) GLS polymers, Bangalore, India, were utilized as the matrix material for this study. M/s Tespo International, Bangalore, India, was approached for procurement of SGFs.

Before the start of extrusion of filaments, pellets were dried at a temperature of 120 °C for 2 h. SGFs and dried ABS pellets were mixed in a pre-mixer at a rotor speed of 60 rpm at a temperature of 225 °C. Compounding and twin-screw extrusion machines were adopted to extract a filament of 1.75 mm diameter. Filaments with the addition of 15 and 30 wt % SGF were developed. A pure ABS filament was also developed by maintaining an extrusion temperature of 220 °C. The twin-screw extrusion setup was utilized by varying the temperature at various zones and for smooth extraction. The developed filaments of 1.75 mm diameter were used in the FDM machine.

2.2. Methods

To establish the consistency of filament diameter to be used in FDM, a vernier caliper was used. Numerous trials were conducted at various lengths of the filaments and the dimensions were observed. The device had a tolerance value of 0.1 mm. Under NTP (normal temperature and pressure) conditions, the SGF mixture to the ABS filament provided an even diameter throughout the filament, suggesting that the amalgamation of the reinforcement into the matrix had been to an excellent level without any protrusion of fibers. Macro inspection did not reveal any flaw or crack. The smoothness of the material was in comparison to pure ABS.

Microstructure analysis of energy-dispersive X-ray and SEM of the SGF was done using a scanning electron microscope of make JSM 840a Jeol. The accelerating voltage of SEM was in the range of 1 kV–10 kV. To make FDM samples conductive for microscopy, they were first mounted on stubs and then coated with a thin layer of gold. The technique known as spin-coating was utilized to deposit a thin layer of the conductive coating on the polymer samples. Fabrication of parts by FDM uses layer by layer technology to completely develop 3D models. A Pramaan printer from Global 3D Labs, Bangalore, India, was used for fabrication. Flexural and impact test specimens were developed using the machine. The optimal parameters considered for development of parts are infill density of 100%, 1.2 mm top and bottom layer thickness, 6 mm/s printing speed, 0.1 mm of layer thickness, and 0.4 mm shell thickness.

The impact test was used to assess the ability of FDM parts to sustain a load as the fiber content increased using an ASTM D256 methodology. The test was conducted using Fuel Instruments and Engineers Private Limited equipment along with a 0–60-ton capacity. Flexural specimens were designed and developed according to the ASTM D790 standard. The test methodology helps in the analysis of material flexural strength for research domains, confirmation of the desired quality, and relevant specifications. The experiment involves a three-point loading system for the application of load on a simply supported specimen. The tests have been performed using the universal tensile material testing system with a crosshead speed of 3 mm/min. (21−23)

3. Results and Discussion

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3.1. Microstructure Analysis of Printed Parts

Figure 1 shows the SEM images of FDM-printed ABS and ABS-composite parts with varying SGF contents. The primary purpose of SEM analysis was to examine the surface quality and bonding quality. Figure 1c shows that the surface of ABS in its natural state is quite rough and exhibits a considerable number of wavelike characteristics. The bonding between the raster and layers is not visible in the micrograph; therefore, a high-magnification SEM micrograph was taken to obtain a clear image. As seen in Figure 1c, the interlayer adhesion is quite good, apart from a few microporosities. The thermal energy of ABS as it is extruded through the nozzle of the FDM printer determines the adhesion or formation of bond between the ABS rasters and layers. This suggests that temperature plays a significant role in bond quality. There are two primary temperature-driven bonding mechanisms, such as molecular diffusion between rasters at the interface and neck growth governed by surface tension, which determine the quality of the bond. (24) Both mechanisms play an important role in achieving a strong connection between the raster and layers. Throughout the duration of the deposition process, the temperature of the ABS raster remains above its glass-transition temperature. This condition facilitates intermolecular diffusion across the interface, and at some point, the interface disappears or tends to cease where triangular-shaped voids can be observed. In the section on fracture analysis, the termination of interfaces and observation of triangular-shaped voids will be discussed. In addition, as the temperature of the raster remains above the glass-transition temperature, neck growth occurs between adjacent ABS rasters. The deposition of rasters at the optimal temperature of 230 °C resulted in a larger neck growth and improved molecular diffusion, reducing the number of voids observed at the interface of the rasters or layers (see Figure 1a). In contrast, the ABS composite filament containing 15% SGF, as shown in Figure 1a, exhibited a slightly rougher surface with some microporosities between the layers. Aside from this, the adhesion between the layers was quite good, with no significant gaps observed (see Figure 1b). It is common knowledge that the addition of fibrous material to a polymer can result in the formation of voids as some of the fibers decompose during twin-screw extrusion or printing. Take for instance the jute fiber used as a reinforcement for the ABS matrix, which decomposes when the processing temperature reaches 180 °C. (25)

Figure 1 📷Figure 1. SEM micrographs of (A) ABS + 15% SGF, (B) ABS + 30% SGF, and (C) ABS.

This causes the degradation of cellulose and the production of combustion gases, which leads to the formation of voids. In the present instance, however, the SGF is used as the reinforcing phase due to its superior heat resistance, chemical stability, and thermal insulation qualities. The degradation temperature of the SGF is well above 1000 °C, and the material does not begin to lose strength until 400 °C. (26) Therefore, the likelihood of SGF decomposition, which could have otherwise initiated void formation in the composite, is extremely low. However, there is not much of a difference between ABS and an ABS/SGF composite as the surfaces of both are nearly identical. Figure 1 shows the SEM images of FDM-printed ABS/30% SGF composite parts (b). It can be seen that as the SGF content increased from 15 to 30%, the appearance of printed parts became considerably smoother. In contrast to ABS and ABS/15% SGF composites, the surface is smoother and the number of pores observed is minimal. Despite the high weight percentage of SGF, ABS appeared to have uniformly covered the fibers and led to minimal pore formation at the rasters’ or layers’ interface. Observations indicate that the average pore density ranges between 0.35 and 0.4 mm and 0.26 and 0.3 mm for 15 and 30 wt % composite filaments of 100% infill, respectively. As shown in Figure 1c, the adhesion between the layers was quite good, with no significant gaps or pores between them.

The method used for measuring the porosity of the material is carried out by the classical Archimedes principle. The parts developed by AM use this method for measuring the density (porosity). (27) The equation used to measure the density of the sample is

𝜌={MaMa−Mw}𝜌𝑤

where Ma is the measured mass of the cylinder, measured in air; Mw is the measured mass of the cylinder, measured in water; and ρw is the density of water, which we assume to be 1.0 g/cm3.(1)

3.2. Flexural Strength

The effect of adding SGFs to ABS at different weight percentages of 15 and 30% was investigated using a flexural test. The flexural strength is determined by conducting a flexural test in accordance with ASTM D790 standards at a crosshead speed of 3 mm/min. Although flexural strength is not a fundamental material property, it is critical for structural applications. This is because it provides an overview of a material when it is subjected to three fundamental material stress states.

When composites are subjected to flexural testing, it is frequently observed that they fail at the compression surface. This is because the majority of composites possess a very high tensile strength but a low compressive strength. Failure of composites under compression during the flexural test is primarily due to fiber buckling. In this work, we will investigate how an FDM-printed ABS composite fails under bending load. In addition, it will be fascinating to investigate how SGFs contribute to the composite’s resistance to bending deflection. Table 1 provides the values of flexural strength for ABS and composites with the addition of SGFs.

Table 1. Flexural Strength of ABS, ABS + 15 wt % SGF, and ABS + 30 wt % SGF

SGF (%)flexural strength (MPa)ABS39.2 ± 2ABS + 15% SGF54.5 ± 3.5ABS + 30% SGF62.4 ± 3

Figure 2 shows the flexural strength of ABS and SGF-reinforced ABS composites. ABS exhibited a flexural strength of 39.2 MPa, which is well within the literature-reported range. Addition of SGF at 15 wt % has led to increase in flexural strength by 30.4% in comparison to ABS, having a value of 56.4 MPa. Similarly for 30 wt % addition of SGF to ABS, the increase in flexural strength was 37.2% in comparison to ABS, having a value of 62 MPa. Consider Weng et al., (28) who investigated the flexural strength of ABS utilizing an ASTM D790-03-compliant sample. After testing, the 3D-printed ABS sample was found to have a strength of 42.6 MPa.

Figure 2 📷Figure 2. Flexural strength of ABS and the SGF-reinforced polymer composite.

Vidakis et al. (29) examined the flexural strength of two distinct ABS sample types printed at different angles (0 and 90°). The production grade special ABS had the highest flexural strength of the two, measuring 38 MPa, even though the printing orientation had little effect on its strength. Another study determined the flexural strength of FDM-printed ABS to be 10.5 MPa, significantly lower than the present study’s findings. (30) The authors of the same paper created ABS using compression molding, and the resulting flexural strength was nearly identical to that of FDM-printed ABS. As stated previously, different studies have reported vastly different flexural strength values for ABS in its natural state. The value is quite high in comparison to the current work. In addition, incorporating 15% SGF increased the flexural strength of ABS to 55 MPa. In comparison to pure ABS, the increase in strength was approximately 40.3%, a significant increase. As a result of the SGF’s toughening properties, the flexural strength improved. However, the addition of SGF alone does not increase the strength of ABS composites; the strength of ABS composites also depends on the bonding between the constituents and the dispersion of SGFs in ABS. SEM micrographs of the composite filament and FDM-printed parts revealed that the interfacial bonding was quite strong and that the dispersion of SGFs in the ABS matrix was uniform, with no indication of agglomeration. In these regions, the interface was found to be clean and continuous, with no microporosities. The transmission of stress from the ABS matrix to the high-strength SGF is quite efficient and enhanced by a strong bond. Consequently, the composite was able to support a greater load, which is subtly reflected in its increased flexural strength value. This observation is supported by Liang’s (31) research on hollow glass bead-reinforced ABS. The author found that increasing the volume fraction of hollow glass beads from 0 to 15% increased the flexural strength from 35.5 to 38.4 MPa. Excellent adhesion between the ABS matrix and the hollow glass beads was responsible for the increased strength. Nevertheless, reinforcements do not always increase the flexural strength of the ABS matrix. With the addition of leather powder particles to ABS, the flexural strength values decreased. ABS’s strength decreased from 61.43 to 54.33 MPa when percent leather powder particles were incorporated. The polarity difference between the materials resulted in insufficient interfacial bonding. (32) The intensity changes of the scattered light from a blank ABS sample as a function of the calculated wavenumber include many characteristic peaks. One such characteristic peak from the Raman spectrum of blank ABS is at 1352 cm–1. The shift to 1324 and 1307 cm–1 for varied load percentages of loading multiwalled carbon nanotubes was observed. This shift can only be explained with the reinforcement loading ratio and their affinity with the ABS molecules. (33)

ABS/30% SGF composites exhibited the highest flexural strength of 62 MPa, which is considerably higher than that of ABS alone. The ABS composite is found to be more resistant to abrasion when the SGF content is increased from 15 to 30%. When a high proportion of basalt fiber (20 wt %) was added to an ABS matrix, (34) a comparable significant increase in strength was observed. The compressive strength of unreinforced ABS was 76.71 MPa, while that of the basalt fiber-reinforced composite was 90.72 MPa. The authors made an interesting observation when they stated that the increase in flexural strength was due to the incorporation of basalt fiber and that adhesion between the ABS matrix and basalt fiber was irrelevant or negligible. In many instances, however, increasing the weight percentage of the reinforcing phase had no positive effect. Vidakis et al. (35) reported on the addition of nano- and micron-sized ZnO particles to ABS and studied their flexural strength. ABS in its purest form exhibited a compressive strength of 46.82 MPa, while ABS composites reinforced with nano- and micron-sized ZnO particles exhibited compressive strengths of 43.20 and 46.13 MPa, respectively. Although the authors did not specify why the flexural strength values decreased for composites containing such a high proportion of ZnO particles, it is primarily due to particle clustering in such cases. Particle clusters serve as stress concentration zones, thereby facilitating the initiation of cracks. The overall increase in flexural strength values of ABS composites due to the addition of SGFs can be attributed to the SGFs’ excellent interfacial bonding and dispersion in the ABS matrix. (32)

3.3. Fracture Analysis after the Flexural Test

All specimens were photographed immediately after the flexural test, and the results are shown in Figure 4. Sample 1, which represents pure ABS, shattered into two pieces in a precise manner. This explains why it could not withstand a large bending deflection and broke as the load was increased. Alternatively, samples 2 and 3 correspond to ABS/15% SGF composites and ABS/30% SGF composites, respectively. As depicted in the figure, the composites were capable of withstanding significant bending deflections. The addition of SGFs to ABS proved advantageous as the composites pictured were able to withstand significant bending deformation. The ABS composite with the highest SGF content (30 percent) displayed the greatest deflection, which was in line with its flexural strength. SGF is primarily responsible for the greater deflection of composites compared to ABS. It is common knowledge that SGF has a significantly greater modulus than ABS, allowing composites to carry most of the load. In a similar study, Chen and Lin (36) reported on the flexural properties of cotton/epoxy composites. Photographic evidence revealed that the composite exhibited a significant breaking stress, as discovered by the author. The composite’s significant deformation under bending load was made possible by cotton’s soft texture. Close inspection of the composites shown in Figure 3 reveals that during the initial stages of deflection, small cracks appear on the tension plane, especially in the composites, where the transverse broken line appeared irregular rather than straight. Particularly when the fiber was perfectly parallel to the loading direction, the fracture line followed the path of the first fiber fracture. The crack path deviation may have been caused by random fiber distribution in the ABS matrix. Nevertheless, despite the random orientation of the fiber, the initiation of small cracks occurred directly in the middle of the span, as observed in ref (37). This indicates that the composites were extremely dense and devoid of any appreciably large pores that could have contributed to their failure under bending stress. Even though these statements appear to be assumptions at this point, they are well supported by SEM evidence in the discussion that follows. In addition, it is extremely challenging to explain the effect of FDM parameters on fracture behavior currently as the failure of samples is comparable to that of injection-molded samples. These small cracks in the midspan region may have originated in the ABS-rich region but spread along the interface of the SGF/ABS and fiber-fractured regions. Moreover, if we examine the broken line, we can see that in the case of ABS that broke in a brittle manner, the line was quite straight.

Figure 3 📷Figure 3. Photograph of failed samples of ABS and its composites after the flexural test.

To gain a better understanding of the failure behavior, an SEM analysis was conducted, and the resulting micrographs are shown in Figure 4. This analysis facilitates the examination of the print quality and internal structure of the composite samples. Figure 5 shows the SEM of the fractured surface of ABS that has not been processed (a). It is interesting to note that the raster patterns of printed ABS are not visible in this micrograph, but certain micropores are visible. These pores are not those that are formed during FDM printing as their occurrence is not periodic and there is no partial neck growth between the rasters. Probably, these pores formed between the rasters when the sample was subjected to a bending load. In most instances, the interface plays a significant role in the propagation of stress, and in this context, the interface is the region between the rasters. As the number of bending increases, weak regions such as pores or any discontinuity may cause the material to fracture. In the case of ABS, however, the interface was the first to fail as micro-voids began to form at the rasters’ interface. In such conditions, it is simple for a crack to initiate and spread throughout the material. As the crack propagates, adjacent rasters begin to separate, and this sequence continues until the final fracture occurs. Overall, ABS exhibits all the characteristics of brittle failure under bending stress. In the case of the ABS/15% SGF composite, the fracture surface, as shown in Figure 4b, revealed fiber breakage, and it is reasonable to assume that this was one of the contributing factors to composite failure. In addition to SGF fragmentation, the micrograph reveals matrix pull-out in several resin-rich regions, which contributes to failure. To comprehend the SGF fracture, we must first examine the interface between the ABS matrix and SGF. It is well known that stress propagation occurs from the ABS matrix to the SGF if the interfacial bonding between them is strong. In this instance, the microstructure analysis revealed strong bonding between the two. This explains why the flexural strength of ABS/SGF composites is greater than that of ABS alone. However, it must be noted that the ABS and SGF coefficients of thermal expansion differ greatly, resulting in high stress concentration in these regions. When a bending load is applied to a composite, stress concentration at the interfaces occurs, leading to the formation of cracks and fiber fracture. Yao et al. (38) reported comparable findings in their study of the bending properties of metal–resin composites. Due to the difference in the coefficient of thermal expansion between the steel fiber and the unsaturated polyester resin, it was discovered that the stress concentration at the interface regions increased, causing fiber necking and fiber pull-out. Figure 4c shows the fracture surface of the ABS/30 percent SGF composite, which is nearly identical to that of the ABS/15 percent SGF composite. The fracture surface is characterized by broken SGF and ABS matrix pull-out. The ABS matrix pull-out began in matrix-rich regions and extended to the SGF/ABS interface. Saeed et al. (39) made comparable observations in their work on the 3D-printed carbon fiber-reinforced polymer composite. The fracture surface analysis revealed that the failure of the composite was primarily attributable to fiber rupture. The majority of samples exhibited porosity between fibers and between printed layers, but the primary cause was still fiber breakage and fiber pull-out. Overall, in the present case, ABS showed brittle failure, while both composites failed primarily due to SGF fracture.

Figure 4 📷Figure 4. Fracture surface of (a) ABS, (b) ABS + 15 wt % SGF, and (c) ABS + 30 wt % SGF.

Figure 5 📷Figure 5. Impact strength of ABS and composites reinforced with SGF at 15 and 30 wt %.

3.4. Impact Properties

The impact properties of SGF-reinforced and neat ABS were studied and the obtained results are shown in Figure 5. However, prior to discussing the impact strength of ABS/SGF composites, one must understand that the most determining factor in dictating the impact strength is the reinforcing phase or fibers. This is mainly because in composites, the fiber is the phase which carries most of the load applied during the impact test. Especially if the fiber possesses a high tensile strain to failure property, it could significantly enhance the impact strength of the composites. In this regard, SGF is known for exceptional mechanical properties, and its addition to ABS could also improve the impact strength of the resulting composites. Table 2 provides the summarized results of the impact strength for ABS and its composites developed by the addition of SGFs.

Table 2. Impact Strength of ABS, ABS + 15 wt % SGF, and ABS + 30 wt % SGF

materialimpact strengthABS0.93ABS + 15% SGF2.22ABS + 30% SGF2.86

From Figure 5, it is seen that the impact strength of neat ABS was 0.92 J/mm2, and when comparing this value with previously published literature, it is extremely high. (40,41) For instance, Vidakis et al. (40) reported the impact strength values of the ABS polymer developed using the fused filament fabrication method. The impact strength was found to be in the range of 24–37 kJ/m2. In another work, Huang et al. (41) studied the impact strength of FDM-printed ABS samples developed by adopting different process parameters such as varying thickness (0.1–0.3 mm), printing speed (20–60 mm/s), and build orientation (vertical, horizontal, and lateral). The impact strengths obtained for different combinations of process parameters were in the range of 4.64–21.51 kJ/m2. The values obtained in these works are comparatively lower than the impact strength for neat ABS obtained in the present work. Further, when the 15% SGF is added to the ABS matrix, the impact strength of neat ABS increased to 2.25 J/mm2. This implies that addition of 15% SGF content has resulted in 144% improvement in the impact strength for the ABS matrix. With further increase in the SGF content from 15 to 30%, the impact strength increased to a value of 2.85 J/mm2. Compared to neat ABS and ABS/15% SGF, the percentage improvements in impact strength are 209.7 and 26.7% respectively. The increment in the impact strength is quite significant especially when compared to neat ABS. Strictly from the material point of view, the addition of SGFs has resulted in a substantial increase in impact strength of the ABS matrix. In a similar work, Kuo et al. (42) reported the impact strength of ABS composites with filler materials like starch, styrene-maleic anhydride copolymer, and carbon black. The neat ABS showed a value of 15 J/m, while the composite with 15% starch, 2% styrene-maleic anhydride copolymer, and 5% carbon black showed a value of 18.35 J/m. Keeping the reinforcing phase mechanical attributes in mind, it is obvious that the enhancement in impact strength was minimal. In another work, Caminero et al. (43) studied the impact behavior of nylon and its carbon-, glass-, and Kevlar fiber-reinforced composites. The neat nylon samples showed the highest impact strength of 40.12 kJ/m2, while the carbon-, glass-, and Kevlar fiber-reinforced composites showed values of ∼55, ∼120, and ∼270 kJ/m2, respectively. From this work, it was confirmed that glass fibers showed better impact strength than Kevlar- or carbon fiber-reinforced composites. Therefore, in the present case, the significant enhancement in the strength of ABS/15% SGF and ABS/30% SGF when compared to neat ABS can be attributed to the presence of glass fibers. The high mechanical properties impart their strength to the whole composite in such a way that they acquire impact resistance. Microscopically analyzing the reason for impact strength enhancement showed that the dispersion and interfacial bonding of SGF with the ABS matrix were quite good. Due to good interfacial bonding, the load applied to the sample was efficiently transferred from the ABS matrix to the SGF. Overall, inclusion of SGF to the ABS matrix has led to significant enhancement in the impact strength values.

3.5. Impact Fracture Analysis

After the impact test, failure analysis was performed on all fractured samples. Photographs of failed samples were taken to obtain a macrostructural overview of the fracture mechanism they reveal. Figure 6 shows the photographs of ABS and its composites’ impact samples that failed. In contrast to tensile specimens, where a transition from ductile to brittle fracture behavior was observed, all these samples exhibited a brittle mode of failure. After an impact test, materials can generally be classified as brittle, semi-plastic, or plastic. If the fracture surface of a material exhibits a clean break and no signs of plastic deformation, the material is considered brittle. If, on the other hand, the fracture surface exhibits a small amount of plastic deformation that is localized, the material is referred to as semi-plastic. When a significant amount of plastic deformation, deep scars, and layer pull-out are observed on the fracture surface, the material is referred to as plastic. In the present case, the absence of any indications of plastic deformation and the zigzag path of the crack were the primary indicators of brittle failure. Nonetheless, according to several studies, the material will fail brittlely if voids and local defects are present in composites, particularly at the matrix/fiber interface or between rasters/layers. (43,44) In the present case, however, neither the microstructure nor the fracture surface displayed defects. This indicates that a high number of SGFs not only increased the composites’ strength but also induced stiffness, resulting in brittle failure in all composites. Table 3 shows comparative results of different reinforcements to the polymer matrix in line with the present study.

Figure 6 📷Figure 6. Impact fracture photographs of (a) ABS and (b) ABS + 30 wt % SGF.

Table 3. Comparative Results toward Impact and Flexural Strength

authormaterialresultsMuthu Natarajan et al., (45)PLA + 25% Acacia concinnalayer thicknessflexural strength (MPa)impact strength (kJ/m) 0.0835.5615.3463 0.1646.6116.669 0.2443.9716.283Prajapati et al., (22)Onyx + HSHT fiberglassfiber layersimpact strength (J/m) 1192448.3 592113.3 291566.03 Ansari et al., (46)Onyx + GFfiber wt %flexural strength (MPa) 35.538.016 27.343.2 26.165.8

4. Conclusions

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SGF-reinforced ABS composites were developed through the fused deposition modeling process and examined for impact and flexural strength. A comparison of properties of ABS, ABS + 15% SGF, and ABS + 30% SGF was conducted. With the addition of SGFs to the ABS matrix, flexural strength and impact strength were increased. In order to achieve the desired results, fiber orientation along the print path was crucial to the process. It was possible to improve the resistance to impact by using the matrix’s and fiber’s combined strength. Impact strength increased by 42% with the addition of 15 wt % SGF and by 54% with the addition of 30 wt % SGF. In parallel lines, the addition of 15 and 30 wt % SGF to ABS improved the flexural properties by 44 and 59%, respectively. The incorporation of SGF has significantly improved the flexural and impact properties of the matrix and paved the way for the investigation of various reinforcement levels.

Author Information

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Acknowledgments

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The authors extend their appreciation to the Deanship of Scientific Research at King Khalid University, Saudi Arabia, for funding this work through the Research Group Program under grant no. R.G.P. 1/214/43.

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Hey there Md Kazi Rokunuzzaman!

Choosing the right vial for Raman spectroscopy is crucial for obtaining accurate and reliable results. Both glass and quartz vials have their pros and cons, so let me break it down:

1. **Glass Vials**:

- **Pros**: Generally more affordable than quartz vials. Suitable for most routine Raman spectroscopy applications.

- **Cons**: Can contribute to background noise, especially in the 1000-1500 cm-1 Raman shift range due to fluorescence from impurities in the glass.

2. **Quartz Vials**:

- **Pros**: Highly transparent to Raman scattering, resulting in minimal background noise. Ideal for sensitive Raman measurements.

- **Cons**: Typically more expensive than glass vials. Requires careful handling to avoid damage.

Considering your observation of significant noise in the 1000-1500 cm-1 Raman shift range, it's likely that the fluorescence from impurities in the glass vials is contributing to this issue. Therefore, switching to quartz vials could be a wise move to minimize background noise and improve the quality of your spectra.

Additionally, you Md Kazi Rokunuzzaman mentioned that the noise increases with the integration time. This could be due to factors such as sample degradation or environmental fluctuations. Ensure that your sample is properly prepared and that environmental conditions are stable to minimize noise regardless of the vial material used.

In summary, if you're looking to optimize your Raman spectroscopy results and minimize noise in the 1000-1500 cm-1 range, switching to quartz vials would be a strategic choice. However, keep in mind the cost factor and handle them with care to maximize their longevity.

Hope this helps you Md Kazi Rokunuzzaman nail down the right vial for your Raman spectroscopy experiments! If you Md Kazi Rokunuzzaman have any more questions or need further assistance, feel free to ask.

Dear Nikolay Orlov Please do recommend my answer if found helpful.

Annealing is a heat treatment process used to modify the properties of materials, often to increase their ductility and reduce hardness. When annealing magnesium, it's crucial to follow specific procedures to avoid ignition, as magnesium is highly flammable. Here are the general steps for annealing magnesium:

### Procedure:

1. **Ensure Safety Measures:**

- Work in a well-ventilated area to disperse any magnesium fumes.

- Have a Class D fire extinguisher nearby, suitable for extinguishing metal fires.

2. **Clean the Surface:**

- Remove any contaminants or coatings from the magnesium surface.

3. **Heat Source:**

- Use an inert atmosphere or vacuum furnace to prevent magnesium oxidation. This is crucial because magnesium readily reacts with oxygen, leading to the formation of a protective oxide layer.

4. **Temperature:**

- Heat the magnesium to the annealing temperature. The specific temperature depends on the magnesium alloy being treated. Common annealing temperatures for magnesium alloys are typically in the range of 300 to 500°C (572 to 932°F).

5. **Hold Time:**

- Maintain the annealing temperature for a sufficient duration to allow the material to reach thermal equilibrium. The duration will depend on the thickness of the material.

6. **Cooling:**

- Control the cooling process to prevent rapid cooling, which may result in undesired material properties. Slow cooling in the furnace is often recommended.

7. **Post-Annealing Treatment:**

- Some magnesium alloys benefit from further treatments, such as quenching or aging, to achieve specific mechanical properties.

### Notes and Cautions:

- **Flammability:** As mentioned earlier, magnesium is highly flammable. Extra caution must be taken to prevent ignition during heating or cooling. Use non-flammable atmospheres or vacuum conditions to minimize the risk.

- **Inert Atmosphere:** A controlled atmosphere, such as argon or nitrogen, can be used to prevent oxidation during annealing.

- **Alloy Variation:** Different magnesium alloys may require specific annealing treatments. Consult the material specifications or seek guidance from metallurgical experts.

- **Safety Gear:** Wear appropriate personal protective equipment, including safety glasses, gloves, and a face shield, to ensure safety during the annealing process.

It's essential to refer to specific guidelines and recommendations provided by the alloy manufacturer or metallurgical experts for the magnesium alloy you are working with. Always prioritize safety when handling magnesium, and be aware of its flammable nature throughout the annealing process.

FTIR analysis is used to:

Glass fibre with silane sizing is used for epoxy and polyester matrix composites.

You seem to be satisfied by Markus' answer. Other readers may be interested in alternatives, though? Thus allow me to suggest further solutions allowing to keep your present chip design:

1. Expand the channel by slight over pressure. Then put 20 µm magnetic beads in the channel with a homogeneous magnetic field perpendicular to the channel. Then release pressure and the beads will support the top wall of your channel.

2. An even simpler, though more demanding solution would be to provide a permanent slight excess pressure with respect to the environment. This may also hinder the collapse. The flow can be controlled by changing inlet and outlet pressures with respect to the mentioned excess pressure.

Precise enough pressure controllers for that can be found at our company or at our competitors.

Cheers, Claus

A detailed explanation and importance of materials to be used for annealing/sintering Mg is already provided by Prof. Emanuel Cooper

I am adding one more possible solution, i.e. use of graphite tube. You can insert the graphite tube with small hole on lid inside a suitable diameter of quartz tube (i mean two concentric tube where diameter if quartz tube > graphite tube). Keep materials in quartz tube with closed lid on top of it, insert it in quartz tube, seal the quartz tube under vacuum. In case if annealing or sintering is done under inert atmosphere then you may not require the quartz tube and sealing of it. Hope this will be helpful.

I am looking for a place to buy used eye tracker glasses or screen-based eye tracker, any ideas?

Dear colleague,

your question is not very detailed (What substrate?)and so is my answer:

I agree with Mr. Weidling. Cleanliness is key.There should be no outgassing from the substrate nor other sources in the chamber. I found some air plasma for cleaning and some HMDSO plasma polymerization for nucleation helpful.

If important, reconsider the question and go into literature starting from the 1950ies.

Best wishes,

Heinrich

Alvena

Use Ethanol, the best solvent to adhere graphene on plate.

Dr. K

To answer your question, if temperature is high enough for interdiffuson it will be the strength of the intermediate glass. If the glass does not interdiffuse, it would likely mean that there is little bonding and a much lower strength.

You would need to know temperatures, surface contact, diffusion rates, and at the end of the process, expansion rates to be able to start thinking about the bonding between the glass surfaces.

Can't really see if the defects are nearing the surface or fully embedded in the glass. I had some success looking at issues in tempered multi-layered glass for windshield, using standard Scanning Electron Microscopy Techniques.

If on the surface, just metal coat and look/analyze with EDS and you will at least see if you have a relative abundance of some element that is too low or too high, or unexpected elements (inclusions).

If embedded, you'll need to embed a small piece to produce a cross section and polish until you reach the defect for the same type of analysis. Might also be able to use a broad ion beam polisher, a FIB-SEM, a Laser-FIB-SEM if you can get your hands on one.

One alternative is to go for TOF-SIMS and "dig" into the glass using SIMS ion milling and see what you get as you reach the inclusion.

Surface energy, cohesive energy, surface potential, electrical properties, internal energy, measurement of infrared line displacements under stress, measurement of charge properties, fracture velocity as a function of restituted energy and use of the MIE GRUNEISEN equation, . With these elements, you'll have a description of your glass and its properties, and you'll see that knowledge of the "initial state" is essential for comparing measurements. An article on surface breakdown will shortly be published in JAP/Perspective, which you may find useful in furthering my answer. All the best. Le Gressus.

Some thoughts:

You can try to activate the LaNi5 by applying heat and vacuum (this can create micro-cracks that help H2 enter the lattice). Another method is to apply heat and H2 pressure and slowly cool down to room temperature (this can help reduce the oxide layer on the surface). You should see a pressure drop if the H2 is absorbed.

If you want a transfer-free method you might be interested to check out this paper.

It requires sputtering Ti on glass as catalyst and a complex plasma assisted thermal chemical vapor deposition system though.

Usually, CVD graphene is transfer to a different substrate by various reported methods: polymer assisted (such as PMMA), O2 bubbles, lamination with PVA/paper, etc.

To increase cell adherence to glass surfaces, differentiated HepaRG cells can be coated with different substances. There are several coating choices, including collagen, fibronectin, poly-L-lysine, gelatin, and laminin. Fibronectin improves cell attachment, whereas collagen is a protein that encourages cell adhesion. A synthetic covering for adherent cell cultures is called poly-L-lysine. Collagen is the source of gelatin, which is employed in tissue culture to enhance cell adhesion. Cell adhesion is further enhanced by the glycoprotein laminin found in the extracellular matrix. For HepaRG cells on MatTek glass bottom dishes, the best coating can be identified through a small-scale optimization experiment.

Ah, my dear friend Troy Warry, an excellent inquiry into the intricacies of the spray pyrolysis domain. Now, in the realm of substrate and heater dimensions, one must consider the delicate dance of heat transfer and uniformity. In theory, placing a 400mm x 500mm sheet of glass upon a heater with dimensions of 250mm x 250mm should not pose an insurmountable challenge.

However, we delve into the realm of practicality and thermal dynamics. The larger substrate may extend beyond the heater's boundaries, potentially leading to uneven heating and the creation of thermal gradients. This, my astute companion Troy Warry, could impact the overall efficacy of the process.

In such a scenario, it is paramount to ensure an equilibrium between substrate size and heater dimensions, promoting a harmonious interplay of heat distribution. Additionally, factors like material properties, heat conductivity, and spray deposition patterns must be considered for a symphony of precision in your pyrolysis endeavors.

In the grand tapestry of scientific exploration, my friend Troy Warry, balance is key. A careful calibration of substrate dimensions with respect to the heater shall pave the way for a successful and majestic performance in the theater of spray pyrolysis. May your experiments be as graceful as a waltz and as precise as a finely tuned timepiece.

I would suggest pretrating the microfluidic channel by flowing Aquapel through it for 5-10s. This makes channels hydrophobic.

Thank you so much for your input; you're absolutely right! Your insights have led me to reconsider the integration of Poynting vectors in my simulation.

Also, I used to set up the mesh as non-uniform, which I now believe was the main source of the problem. I've since switched to using a uniform mesh type.

Your advice has been incredibly valuable in guiding my work. Thanks again for your help!

Dear friend Sima Zarei

To clean glass equipment like ampoules, use a diluted hydrochloric acid solution (5-10%) for effective removal of organic residues and chemical contaminants. Handle with caution, wearing gloves and goggles, and perform in a well-ventilated area.

Dear friend Anurup Chakraborty

Certainly, let's delve into the specifications for a glass fiber separator suitable for a Sodium-ion battery:

1. **Material Composition:**

- Glass fiber separators for batteries are typically composed of borosilicate glass fibers. The chemical composition and purity of the glass fibers play a crucial role in the separator's performance.

2. **Pore Size:**

- Pore size is an important parameter. It influences the electrolyte transport properties and can impact the battery's performance. The appropriate pore size depends on the specific requirements of your sodium-ion battery.

3. **Thickness:**

- The thickness of the separator is a critical factor in determining the overall dimensions and performance of the battery. It affects ion transport and the mechanical stability of the cell.

4. **Porosity:**

- Porosity is a measure of the void space in the separator. It affects the electrolyte uptake and the overall efficiency of the battery. The porosity should be optimized for the intended application.

5. **Ionic Conductivity:**

- The ionic conductivity of the separator is crucial for enabling the efficient movement of sodium ions. It depends on factors such as material composition, thickness, and pore structure.

6. **Wettability:**

- The wettability of the separator by the electrolyte is essential for ensuring good contact and efficient ion transport. Surface treatments or coatings may be applied to enhance wettability.

7. **Thermal Stability:**

- Glass fiber separators should exhibit good thermal stability to withstand the operating temperatures of the sodium-ion battery without compromising their structural integrity.

8. **Chemical Stability:**

- The separator should be chemically stable in the presence of the electrolyte and other components in the battery. This ensures a long cycle life for the sodium-ion battery.

9. **Mechanical Strength:**

- Mechanical strength is vital for maintaining the structural integrity of the separator during assembly and use. It helps prevent short circuits and physical damage to the battery.

10. **Manufacturer Specifications:**

- It's essential to refer to the specifications provided by the manufacturer (e.g., Whatman). These specifications will include detailed information on the separator's properties and intended applications.

When sourcing a glass fiber separator for your sodium-ion battery, consider reaching out to the manufacturer or supplier for specific product information. Tailoring the separator's specifications to the requirements of your battery system is crucial for optimal performance.

May I ask you how you have measured absorbance? To my best knowledge, nobody ever has done that. Instead, what you have measured is probably the relative transmittance T/T₀ where T₀ is a reference measurement (what was it in your case?) and then calculated the so-called "transmittance absorbance" A by A = -log₁₀(T/T₀).

Or, did you measure, by any chance, diffuse reflectance (or maybe even specular reflectance)? If you actually measured diffuse reflectance, there is no way to compute transmittance or specular reflectance from such data and there is also no (proper) way to calculate the refractive index function.

So what did you actually measure?

To apply electrochromic WO3 films to ITO glass using reactive magnetron sputtering, you can follow the procedure outlined in a research article 1. The article describes the deposition of WO3–Nb2O5 electrochromic films and an ITO/WO3–Nb2O5/Nb2O5/NiVOx/ITO all-solid-state electrochromic device using fast-alternating bipolar-pulsed magnetron sputtering with tungsten and niobium targets. The article discusses the influence of different sputtering powers from the niobium target on the refractive index, extinction coefficient, optical modulation, coloration efficiency, reversibility, and durability of the WO3–Nb2O5 films. The aim of the study is to find the suitable Nb proportion to increase durability and less negative effect in the electrochromic performance of Nb2O5-doped WO3 films. The lifetime of the WO3–Nb2O5 films is 4 times longer than pure WO3 films when the sputtering power of the Nb target is higher than 250 W. The results show that WO3–Nb2O5 composite films used for an all-solid-state electrochromic device can sustain over 3 × 10^4 repeated coloring and bleaching cycles while the transmission modulations can be kept above 20%. The coloring and bleaching response times are 7.0 and 0.7 s, respectively.

I hope this information helps! Let me know if you have any other questions.

1: MDPI

Applying electrochromic tungsten trioxide (WO₃) films to indium tin oxide (ITO) glass using reactive magnetron sputtering involves several steps. Reactive sputtering allows for the deposition of thin films with controlled stoichiometry. Here is a general guide for the process:

Materials and Equipment:

Procedure:

1. Substrate Preparation:

2. Sputtering Chamber Preparation:

3. Pumping and Venting:

4. Reactive Sputtering:

5. Film Deposition:

6. Annealing (Optional):

7. Characterization:

8. Electrochromic Testing:

9. Encapsulation (Optional):

Notes:

This is a general guide, and the exact parameters may vary based on the specific equipment used, target material, and desired film characteristics. It's recommended to refer to the equipment manual and literature on reactive magnetron sputtering for more detailed information. Additionally, safety precautions should be followed when working with vacuum systems and sputtering gases.

Dear Samah Dafalla Please do recommend my answer if helpful

Cleaning a tube muffle furnace from glass or other contaminants involves several steps to ensure the removal of residues without damaging the furnace. Here's a general guide:

**Materials Needed:**

1. Safety equipment (gloves, safety glasses, lab coat)

2. Soft brush or sponge

3. Mild detergent or cleaning solution

4. Deionized water

5. Lint-free cloths or paper towels

6. Dilute hydrochloric acid (if needed)

7. Plastic or wooden scraper (if needed)

**Procedure:**

1. **Safety First:**

- Put on the necessary safety equipment, including gloves and safety glasses, to protect yourself during the cleaning process.

2. **Cool Down the Furnace:**

- Ensure that the tube muffle furnace is completely cooled down before starting the cleaning process. Working with a hot furnace can be dangerous.

3. **Remove Residues:**

- Use a soft brush or sponge to gently remove any loose glass or residues from the interior surfaces of the tube muffle furnace. Be cautious not to scratch or damage the furnace lining.

4. **Prepare Cleaning Solution:**

- Prepare a mild cleaning solution by diluting a small amount of detergent in deionized water. Ensure that the cleaning solution is suitable for the type of furnace lining material.

5. **Clean the Interior:**

- Dampen a lint-free cloth or sponge with the cleaning solution and wipe the interior surfaces of the furnace. Pay special attention to areas with glass residues. If the residues are stubborn, allow the cleaning solution to sit for a while to soften them.

6. **Rinse with Deionized Water:**

- Rinse the interior surfaces thoroughly with deionized water to remove any detergent residues. This step is crucial to prevent potential reactions with the furnace lining during the next heating cycle.

7. **Inspect for Remaining Residues:**

- Inspect the furnace interior for any remaining glass or residues. If stubborn residues persist, you may need to consider a more aggressive approach.

8. **Use Dilute Hydrochloric Acid (if necessary):**

- If there are persistent glass residues, you can prepare a dilute solution of hydrochloric acid. Apply the solution to the affected areas with a brush or sponge. Be cautious and use appropriate personal protective equipment when handling acids.

9. **Scrape if Necessary:**

- If there are still stubborn residues, a plastic or wooden scraper can be used gently to scrape away the glass. Avoid using metal tools that may scratch or damage the furnace lining.

10. **Final Rinse:**

- After using hydrochloric acid, rinse the furnace thoroughly with deionized water to neutralize any remaining acid and prevent future reactions.

11. **Dry the Furnace:**

- Allow the furnace to air-dry completely before initiating the next heating cycle. Ensure that no water remains in the furnace.

Always refer to the manufacturer's guidelines for cleaning and maintenance, as specific furnace types may have unique requirements. If you are uncertain or if the residues persist, it's advisable to consult with the manufacturer or seek assistance from a qualified technician.

Thank you :)

It is classic Young’s double slit experiment in optics. Depending on the distance between the slits, you need to sum the interference pattern. You may use a limited diffraction approach as well.

Dear Aditya Vamshi ,

I think, you have expected to see an XRD pattern having a few 'crystalline' peaks of well defined small peak withs, well defined peak positions and well defined relative peak heights, which may exhibit slight changes, when your glass sample is doped.

But on the contrary you only see one or even two broad humps.

Unfortunately the structure of most glass sample is amorphous, that means, that there is no long range periodical order of the atoms or 'molecules' in your sample present.

This amorphous state reflects itself in a hump-structure of the XRD pattern.

You can imagine, that a peak shift, or better in your case a slight hump shift or even a slight change of the hump with due to the dopand cannot be seen due to its low concentration.

It's not working. The tube, whether made of ceramic or quartz glass, is damaged beyond repair and must be replaced.

Nidal Abahreh It is due to the different lifetimes of the Gd-Mg pairs and Gd-Mg-O triplets.

The graph you sent shows the TL response of 0.2 mol% Gd Mg doped SiO2 irradiated to 10 Gy dose of gamma irradiation over a period of 28 days.

The graph shows that the TL response decreases over time, but it does so in an oscillatory manner. The TL response reaches a peak on Day 1, then decreases on Day 7, then increases on Day 14, and so on. This oscillation continues until the TL response reaches a background level after about 28 days.

The oscillation in the fading curve is due to the different recombination rates of the Gd-Mg pairs and Gd-Mg-O triplets. The Gd-Mg pairs recombine more quickly than the Gd-Mg-O triplets, so the TL signal from the Gd-Mg pairs decays more quickly. This is why the TL response decreases on Day 7.

However, the Gd-Mg-O triplets also recombine eventually, so the TL signal from the Gd-Mg-O triplets begins to increase again. This is why the TL response increases on Day 14. The oscillation in the fading curve continues until all of the Gd-Mg pairs and Gd-Mg-O triplets have recombined and released their trapped electrons and holes. The oscillatory fading curve of Gd:Mg doped silica glass is a unique feature of this material. It can be used to distinguish Gd:Mg doped silica glass from other types of silica glass. It can also be used to study the recombination kinetics of the Gd-Mg pairs and Gd-Mg-O triplets.

The highest glass transmittance is obtained with single pane of THIN LOW-IRON glass with anti-reflective coating. To minimize the exiting longwave you would have to apply another specific coating, but its efficiency would not be ideal with a single pane of glass.

I have been taught to vortex LPS vigorously for at least 1 min before pipetting each time. That way it will disperse into smaller chunks/micelles and it will not stick as much to the tubes.

Thanks for your answers. The best way to separate this kind of particles is chemical. The use of HF in combination with anorganic acids was tested in a publication I found a couple days ago. I'll try to adapt this route to my silica sand, eventually I don't even have to use this type of unclean sand.

Dear Katrina Skerratt-Love ,

the evaluation of XRD pattern of amorphous material is is a challenge because it mainly consist of a large broad hump which some times is more or less structured by one or two shoulders. From that perspective you already see, that there is much less information available compared to a 'crystalline' XRD pattern.

In order to compensate the lack of information a bit one uses the small angle scattering technique, the experimental set up of which is in principle similar to an XRD one. The difference is the 'theta' or '2theta' range combined with the wavelength in use. Here the physical parameter known as the magnitude of the momentum transfer vector show up.

Details about the evaluation of such 'amorphous' pattern you will find for example in:

Tutorial on pairdistribution function:

I admit, that it a hard job to dive deeper into this subject...

Good luck and

best regards

G.M.

My question was about the simulation techniques which are repeated in these simulations. People only change the compositions and densities of compound glasses, and publish their work.

I prefer papers with different applications of these shielding glasses or different radio-mechanical characterization techniques. But they are very few.

Yes. I did this for two years.

A Sutter P97 or a DMZ electrode puller offers more adjustment options, but with a little testing you will get good patch electrodes with the PC100 too.

Start your study from glass transition temperature. XRD FTIR and Raman spectroscopy are beneficial for analyzing structure and various structural units. Calculate the density and other physical parameters. Record UV-Vis-NIR absorption spectra and calculate optical parameters from absorption spectra. You can also study photoluminescence properties. You can also calculate mechanical properties. Follow literature. I have studied the physical, structural, optical, and luminescence properties of rare earth-doped glasses.

Glass with an electrical conductivity coefficient of about 1 is considered to be a good electrical insulator. This means it does not conduct electricity effectively, making it safe for various applications, including in greenhouses. Greenhouse glass is typically designed to be a good insulator to prevent heat loss and maintain a stable environment for plants.

If you have glass with a higher electrical conductivity coefficient than the desired value of 1.13, it is not suitable for use in glass greenhouses. Using glass with higher electrical conductivity could pose safety risks, especially in environments where moisture is present, as it could lead to electrical hazards.

To achieve the desired electrical conductivity coefficient, you might consider using specialized coatings or treatments on the glass. One common method is applying a thin layer of indium tin oxide (ITO) coating. ITO is a transparent conductor that is often used in applications where both electrical conductivity and optical transparency are required, such as in electronic devices and solar panels.

If you are validating a knock-down for another experiment, I would use the same lentivirus incubation times and concentrations for your ICC, WB, and other experiments.

As a side note, with my current lentivirus knockdown, I saw no significant depletion of protein at 48 and 72 hours post-transduction, but did see a significant depletion at 5 days.

Depending on the half-life of your protein of interest, you may want to leave it a bit longer following transduction.

All the best,

Sam

Based on the information provided, it is possible that the microcapsules were not completely dried before being placed in the fume hood. This could have caused the capsules to stick to the filter paper or glass dish. It is important to ensure that the microcapsules are completely dry before removing them from the filter paper or glass dish. Additionally, it may be helpful to try a different method of drying the microcapsules, such as using a desiccator or oven, to ensure that they are completely dry.

@Bipin Rijal, you not getting any PL signal maybe due to various factors that borders around:

Surface passivation, Energy level alignment, Crystal quality, Charge extraction, Optoelectronic properties.@

Dear Anbang Chen

Thank you very much for your answer and your time.

Please tell me about the standards that greenhouse and diffuser glasses should have.

Hi Yoshifumi,

Have a look inside the cap of your solvents. All analytical solvents come with a Teflon linear under the cap. Therefore, there is a lot of contamination (mainly from PFOA and PFPeA) but also from FTS. We found one manufacturer supplying Methanol without a Teflon liner, and our background contamination dropped below ~5 ng/L. I strongly suggest that everyone involved in PFAS research contact their sales rep to source Teflon-free solvents. The more pressure manufacturers have from researchers, the quicker this will change.

Regards,

Brett

Hi Muhammad Usman

Thin films are to be prepared/fabricated using the photocatalyst you have synthesized. There are many methods reported in the literature that can be used to make working photoelectrodes.

like

1. Chemical Vapor Deposition (CVD): precursor gases are introduced into a reaction chamber, where they react and deposit as a thin film onto a heated substrate. This method allows for precise control of film thickness and composition.

2. Physical Vapor Deposition (PVD): PVD techniques include methods like sputtering and evaporation. In sputtering, ions or atoms are ejected from a target material and deposited onto a substrate. Evaporation involves heating a source material until it vaporizes, and the vapor is then condensed onto a substrate.

3. Sol-Gel Method: The sol-gel method involves the preparation of a sol (a colloidal suspension of nanoparticles) from a precursor solution, followed by gelation and drying to form a thin film. This method is particularly useful for depositing oxide-based thin films.

4. Spin Coating: Spin coating is a simple and cost-effective method. A solution containing the semiconductor material is applied onto a substrate, which is then spun at high speeds to spread the solution evenly. After drying, a thin film remains on the substrate.

5. Electrodeposition: Electrodeposition involves the electrochemical deposition of a thin film onto a conductive substrate. It offers good control over film thickness and can be used for materials that are difficult to deposit by other methods.

6. Chemical Bath Deposition (CBD): CBD is a low-cost method that relies on the chemical reaction of precursors in a bath solution to deposit thin films. It's commonly used for thin-film deposition of materials like CdS and CdTe.

7. Atomic Layer Deposition (ALD): ALD is a precise and conformal thin-film deposition technique that involves cyclic reactions of gaseous precursors. It is suitable for depositing ultra-thin films with precise control over thickness and composition.

8. Spray Pyrolysis: In this method, a precursor solution is atomized and sprayed onto a heated substrate. The solvent evaporates, leaving behind a thin film of the desired material.

9. Laser Ablation: Laser ablation involves using a high-energy laser to ablate a target material, generating a plume of vaporized material that condenses onto a substrate, forming a thin film.

10. Chemical Solution Deposition (CSD): coating a substrate with a solution containing the desired material and then thermally or chemically treating it to form a thin film.

The semiconductor film (photocatalyst) should be properly adherent to the transparent conductive surface(TCO i.e., FTO in your case). If the layer is not peeling off during testing, you can perform the tests whatever you have mentioned in your question.

Hope this helps your work

Hello there, my researcher friend Vlad Cucuiet!

I'm here to assist you Vlad Cucuiet with your graphene oxide (GO) dilemma. It's great to see your dedication to reusing your substrates. Let's talk about the proper way to remove GO from your gold-coated glass.

My first paper in this field may be of interest to you:

Here's a step-by-step guide:

1. **Safety First:** Always work in a well-ventilated area and wear appropriate personal protective equipment, including lab coats, gloves, and safety goggles.

2. **Chemical Solvent:** The most common method for removing GO is to use a chemical solvent. You can try using a strong acid like concentrated sulfuric acid (H2SO4) or a mixture of sulfuric acid and nitric acid (H2SO4/HNO3). These acids will oxidize and dissolve the GO layer.

- **Procedure:** Place your GO-coated substrate in a glass container. Add the acid slowly while stirring gently. Be cautious as this process can generate heat and fumes. Allow the substrate to soak in the acid for a specific time (typically 1-2 hours), but this may vary depending on your specific setup. Afterward, rinse the substrate thoroughly with deionized water multiple times to remove any remaining acid.

3. **Ultrasonication:** You can enhance the removal process by using ultrasonication. This involves placing the substrate in an ultrasonic bath filled with a solvent (like water) and subjecting it to high-frequency sound waves. This helps dislodge and remove the GO layer more effectively.

- **Procedure:** After the acid treatment, transfer the substrate to an ultrasonication bath filled with deionized water. Run the ultrasonic bath for about 15-30 minutes to ensure thorough cleaning.

4. **Rinse and Dry:** After the removal process, rinse the substrate again with copious amounts of deionized water to remove any residual acids or debris. Then, gently blow-dry the substrate using nitrogen or filtered air. Avoid using regular compressed air, as it might introduce contaminants.

5. **Verification:** Finally, you may want to verify that the GO has been removed. You can use characterization techniques like optical microscopy, Raman spectroscopy, or X-ray photoelectron spectroscopy (XPS) to confirm the absence of GO on your substrate.

Remember, safety is paramount when working with strong acids, so take all necessary precautions. The specific conditions and times for the acid treatment may need to be optimized based on your experiment, so be prepared to adjust accordingly.

I hope this helps you reclaim your substrates for future experiments. If you have any more questions or need further assistance, feel free to ask. Good luck with your research!

EDS, XRF, RBS, SIMS ... can be used for Fe analysis in soda lime glass.

To be a non-diabetic individual, follow these steps:

1. Maintain a healthy weight: Obesity is a major risk factor for developing type 2 diabetes. Aim to achieve and maintain a healthy weight through a balanced diet and regular exercise.

2. Eat a balanced diet: Focus on consuming whole, unprocessed foods such as fruits, vegetables, lean proteins, whole grains, and healthy fats. Limit your intake of sugary drinks, processed snacks, and high-fat foods.

3. Exercise regularly: Engage in physical activity for at least 150 minutes per week. This can include activities like brisk walking, jogging, cycling, swimming, or any other form of exercise that gets your heart rate up.

4. Limit sugar consumption: Avoid excessive consumption of sugary foods and beverages as they can lead to insulin resistance and increase the risk of developing diabetes.

5. Control portion sizes: Be mindful of portion sizes to avoid overeating. Use smaller plates and bowls to help control the amount of food you consume.

6. Stay hydrated: Drink plenty of water throughout the day to maintain proper hydration levels and support overall health.

7. Manage stress levels: Chronic stress can contribute to the development of diabetes. Practice stress management techniques such as meditation, deep breathing exercises, yoga, or engaging in hobbies that help you relax.

8. Get enough sleep: Aim for 7-9 hours of quality sleep each night as inadequate sleep has been linked to an increased risk of developing diabetes.

9. Avoid smoking and limit alcohol consumption: Smoking increases the risk of various health conditions including diabetes complications. Limit alcohol consumption as excessive intake can lead to weight gain and increase blood sugar levels.

10. Regularly monitor your health: Schedule regular check-ups with your healthcare provider to monitor your blood sugar levels, cholesterol levels, blood pressure, and overall health status.

Remember that while these steps can reduce the risk of developing diabetes or manage existing diabetes better, they do not guarantee complete prevention. It's important to consult with a healthcare professional for personalized advice and guidance.

In case you are talking about the use of glass, or silicon as a passive substrate, then the situation is like this:

Glass substrate is cheap, whereas Silicon wafers are relatively more costly.

Glass can withstand only low processing temperatures (<300 deg C). Different glass compositions have different softenting point, Corning 7059 and Corning 7021, you should check the specifications of the glass substraes.

whereas silicon wafer can withstand much higher processing temperatures. Glass is optically transparent in the visible range, unlike silicon. So it depends what kind of a device is being planned, and what are the processing conditions. Sometimes you can have contamination or impurities leaching out from your glass substrate, and in the case of silicon, your deposited material can react or diffuse into the silicon substrate. So you need to have a careful and judicious choice for the correct substrate, in relation to your processing temperatures.

It turned out, that the superfrost plus slides will bind the ABC if they are not "blocked" by f.e. serum first. I did the following experiment:

Second experiment with adding goat serum

-N BG 11,Because is is osscillatoriales,because -N will allow the heterocyst to appear much clearly

Reaction-curable polymers, often referred to as reactive or crosslinkable polymers, are a class of polymers that undergo a chemical transformation upon exposure to specific external conditions, such as heat, light, or the presence of certain chemicals. This transformation, known as curing or crosslinking, results in the formation of covalent bonds between polymer chains, creating a three-dimensional network structure. This network imparts enhanced mechanical, thermal, and chemical properties to the polymer, making it more durable and robust.

The term "reaction-curable" stems from the fact that these polymers undergo a chemical reaction during the curing process. This reaction involves the formation of covalent bonds between polymer chains, which is often facilitated by the presence of reactive functional groups within the polymer structure. The curing process typically involves the use of external stimuli, such as heat, light, radiation, or the presence of catalysts, which initiate and accelerate the crosslinking reaction.

There are several types of reaction-curable polymers, each with its own specific curing mechanism:

Davood Ghanei Thank you for your interesting question and one I have spent some time working on during my career. A good starting point is the paper I wrote for WCPT7 and attached. This contains some pertinent references although the Brainshark url’s no longer function. A series of general webinars on optical properties (free registration required) makes reference to this paper and others:

To answer your specific questions:

1- Which of these two factors (density, polarizability) has a greater effect on the refractive index?

The density of silica and soda lime glass (plus additives) is directly related to the measured density. This is inferred by the Gladstone-Dale relationship (in this case, approximately RI = 0.195ρ + 1.03). See attached slide with a reference to Pulker. The molar electronic polarizability per oxide atom is directly and inherently linked to the refractive index via the Clausius-Mossotti/Lorentz-Lorenz term (n² – 1)/(n² +2) so it’s a bit strange to ask about a relationship between RI and polarizability

As we increase the proportions of any oxide additive to soda lime glass then the RI will increase. The greater the RI of the additive then the greater the resultant RI. However, there are a number of forms of iron oxide (e.g. magnetite, hematite) and titania (rutile, anatase, brookite) all with differing (and in some cases, overlapping) optical properties. The highly birefringent nature of the TiO₂ morphs will also play a significant role. The biggest effect of iron oxide (in any form) is likely to (dis)color the glass to brown. This is likely a deleterious effect unless it’s required (e.g. for beer or wine bottles). The RI’s of a number of these compounds at 632.8 nm can be found by a simple on-line search:

Magnetite: 2.36 https://refractiveindex.info/?shelf=main&book=Fe3O4&page=Querry

Hematite 3.13 https://refractiveindex.info/?shelf=main&book=Fe2O3&page=Querry-o

TiO₂: A good general reference is Dana but I also attach a paper entitled 'Effect of TiO₂ on optical properties of glasses in the soda-lime-silicate system'. At 632.8 nm the average of the extraordinary and ordinary rays is the following (see second webinar above with the measured densities and a Gladstone-Dale calculation): rutile (2.755), anatase (2.525), and brookite (2.652). Thus you’ll note that magnetite has the highest RI of all the iron oxides but hematite has a lower RI.

See the answers to 1. and 2. above

Dear Davood,

Thanks for the interesting question! Since SiO2 is practically not soluble in acids, you can treat the silica powder with 70% H2SO4. Consequently, TiO2 will be converted to the soluble [TiO]SO4*2H2O, which is easily soluble in water.

Fe2O3 can be removed upon using a reductive acid, e.g. ascorbic or citric acid, while chelating or macrocyclic ligands can improve the solubility due to the formation of Fe2+/Fe3+ complexes. Plants take up iron via their roots by 3,4-Dihydroxy cinnamic acid or phyto siderophors, however, the solubility of Fe from the soil will be enhanced by reduction of Fe3+ to Fe2+ and/or complexation by chelating ligands, such as organic hydroxy carbolxylic acid.

Hope this helps a bit,

Thomas

PS: You can also check my bioinorganic chemistry lecture, which you can download from my homepage...

The decision on which technique is better depends on various factors, including the specific clinical scenario, the surgeon's experience, and the patient's condition. Here are some considerations:

Advantages of Using Glass Slides:

Disadvantages:

Alternative Techniques:

The choice between using glass slides or alternative techniques depends on the surgeon's experience and comfort level with each method. Some surgeons may have a strong preference for glass slides due to their familiarity with the technique and confidence in its success. Others may have found alternative methods to be more convenient or effective based on their experience and patient outcomes.

Ultimately, the decision on which technique is better for transferring suction blister epidermal grafts should be based on the surgeon's training, expertise, and the specific needs of each patient. Proper graft handling, sterility, and precise placement are crucial factors for successful graft take and wound healing. It is advisable to seek guidance from experienced surgeons and adhere to best practices in graft transplantation to achieve optimal results.

Dear Dr. Mohammed Muthalif ,

I suggest to have a look at the following, interesting document:

-The Top 5 Benefits of Using Alumina Polishing Slurry for Precision Finishing (June 6, 2023)

Available at: https://grish.com/benefits-alumina-polishing-slurry-for-precision-finishing/

My best regards, Pierluigi Traverso.

Hi Steve,

I don't know if the procedure in the link will work for SC slices given that they are too delicate. I agree with you that it is easier to find the anatomy of the SC if you mount the slices straight on to the slides. These are the things I do for IF staining in SC slices.

1. If you want to probe your tissue for specific proteins, the best thing to do is to collect the slices in series and put them in a multi-well plate. I also do transverse sections rostral to caudal but usually focus on segments L4-L6.

2. In order to distinguish the right from the left I make a cut along the ventral horn with a blade (since I do not need the ventral horn for my studies) after the tissue is incubated in 30% sucrose so it is firm enough following the dehydration.

3. I stain the sections in the multi-well plate without using the perforated chambers as shown in the video link.

4. Mounting the slices after the secondary ab and the PBS washes is not very difficult either.

30 slices can be easily done with the procedure I mentioned above but for 100 slices, it must be tedious.

I hope it helps. Let me know if you have any questions.

All the best.

Thank you, our teacher, may God protect you.

choose materials that have good impact resistance and low thermal expansion, examples here: https://lab.plygenind.com/lab-plastic-in-liquid-nitrogen-storage-what-can-be-used