Heat - Science topic

The hydrosphere helps regulate Earth's temperature and climate. The ocean absorbs heat from the sun and interacts with the atmosphere to move it around Earth in air currents. Once received by radiation or convection thermal energy is distributed through the atmosphere and the hydrosphere by convection and conduction. The motion of the hydrosphere and the exchange of water between the hydrosphere and cryosphere is the basis of the hydrologic cycle. The continuous movement and exchange of water helps to form currents that move warm water from the tropics to the poles and help regulate the temperature of the Earth. The hydrosphere helps regulate Earth's temperature and climate. The ocean absorbs heat from the sun and interacts with the atmosphere to move it around Earth in air currents. Evaporation caused by atmosphere causes the water molecules from the hydrosphere to form water vapour and move upwards. Both the atmosphere and hydrosphere emit and absorb infrared radiation, influencing heat exchange between Earth's surface and space. Conduction: Direct contact between warmer and cooler regions within the atmosphere and hydrosphere allows some heat transfer. The water cycle is driven primarily by the energy from the sun. This solar energy drives the cycle by evaporating water from the oceans, lakes, rivers, and even the soil. Other water moves from plants to the atmosphere through the process of transpiration. When energy from the Sun reaches the Earth, it warms the atmosphere, land, and ocean and evaporates water. The movement of water from the ocean to the atmosphere to the land and back to the ocean the water cycle is fueled by energy from the Sun. About 23 percent of incoming solar energy is absorbed in the atmosphere by water vapor, dust, and ozone, and 48 percent passes through the atmosphere and is absorbed by the surface. Thus, about 71 percent of the total incoming solar energy is absorbed by the Earth system. As this occurs, liquid water absorbs energy, causing it to evaporate and form water vapor. The process of evaporation absorbs tremendous amounts of incoming solar energy. Through the process of latent heating, energy is transferred into the atmosphere when the water vapor condenses during the formation of clouds. The sun provides what almost everything on Earth needs to go—energy, or heat. Heat causes liquid and frozen water to evaporate into water vapor gas, which rises high in the sky to form clouds. Clouds that move over the globe and drop rain and snow. This process is a large part of the water cycle. The uneven distribution of heat leads to convection currents that “try” to equalize heat everywhere. Simply, heated air at the equator rises up, and spreads north and south towards the poles. There it gradually cools, sinks down, and then flows back across the Earth surface to the equator. Ocean currents act much like a conveyor belt, transporting warm water and precipitation from the equator toward the poles and cold water from the poles back to the tropics. Thus, ocean currents regulate global climate, helping to counteract the uneven distribution of solar radiation reaching Earth's surface.

Ocean currents transfer heat through convection. Convection is the process of heat transfer by the movement of fluids such as water. When warm liquid is forced to travel away from the heat source, it carries energy with it. Convection is an important mechanism for heat transfer in the atmosphere and ocean. Because of its low density, warm air or water rises, creating vertical currents that carry heat upward. The convection cycle is complete when the cooler air or water is replaced by the rising warm air or water. Heat is transferred in a northward direction throughout the North Atlantic. This heat is absorbed by the tropical waters of the Pacific and Indian oceans as well as of the Atlantic and is then transferred to the high latitudes, where it is finally given up to the atmosphere. Ocean currents transfer heat through convection. Convection is the process of heat transfer by the movement of fluids such as water. When warm liquid is forced to travel away from the heat source, it carries energy with it. Energy from the Sun is the driver of many Earth System processes. This energy flows into the Atmosphere and heats this system up it also heats up the Hydrosphere and the land surface of the Geosphere, and fuels many processes in the Biosphere. Energy is transferred between the Earth's surface and the atmosphere in a variety of ways, including radiation, conduction, and convection. Conduction is one of the three main ways that heat energy moves from place to place. The other two ways heat moves around are radiation and convection. Ocean currents act much like a conveyor belt, transporting warm water and precipitation from the equator toward the poles and cold water from the poles back to the tropics. Thus, ocean currents regulate global climate, helping to counteract the uneven distribution of solar radiation reaching Earth's surface. The uneven distribution of heat leads to convection currents that “try” to equalize heat everywhere. Simply, heated air at the equator rises up, and spreads north and south towards the poles. There it gradually cools, sinks down, and then flows back across the Earth surface to the equator. There the cycle is repeated. Heat absorbed by the ocean is moved from one place to another, but it doesn't disappear. The heat energy eventually re-enters the rest of the Earth system by melting ice shelves, evaporating water, or directly reheating the atmosphere.

Sorry not familiar with udf profile writting. Hence, I cannot help :(

Thank you so much!

On its own, methane is 30 times stronger than CO2. It contributes between 10-25% of global warming and though it remains in the atmosphere for less time than CO2 does. Imagine these gases as a cozy blanket enveloping our planet, helping to maintain a warmer temperature than it would have otherwise. Greenhouse gases consist of carbon dioxide, methane, ozone, nitrous oxide, chlorofluorocarbons, and water vapor. This is how much a gas called SF6 (sulphur hexafluoride) is stronger than CO2 in terms of global warming potential. You read right: SF6 is the most potent greenhouse gas in existence with a global warming potential of 23,900 times the baseline of CO2. A powerful greenhouse gas, able to absorb far more heat than carbon dioxide, methane is made of one carbon and four hydrogen atoms. It is found in very small quantities in the atmosphere but is able to make a big impact on warming. Methane gas is also used as a fuel.On a per molecule basis, chlorofluorocarbons are very potent. Methane is also pretty potent. However, water vapor is the most effective because there is so much more of it in the atmosphere. Greenhouse gas molecules in the atmosphere absorb light, preventing some of it from escaping the Earth. This heats up the atmosphere and raises the planet's average temperature. The level of carbon dioxide in Earth's atmosphere has been rising consistently for decades and traps extra heat near Earth's surface, causing temperatures to rise. Greenhouse gases act similarly to the glass in a greenhouse: they absorb the sun's heat that radiates from the Earth's surface, trap it in the atmosphere and prevent it from escaping into space. The greenhouse effect keeps the Earth's temperature warmer than it would otherwise be, supporting life on Earth. Greenhouse gases effectively absorb thermal infrared radiation, emitted by the Earth's surface, by the atmosphere itself due to the same gases, and by clouds. Atmospheric radiation is emitted to all sides, including downward to the Earth's surface. Methane (CH4) persists in the atmosphere for around 12 years, which is less time than carbon dioxide, but it is much more potent in terms of the greenhouse effect. In fact, pound for pound, its global warming impact is almost 30 times greater than that of carbon dioxide over a 100-year period. Methane is more than 28 times as potent as carbon dioxide at trapping heat in the atmosphere. Over the last two centuries, methane concentrations in the atmosphere have more than doubled, largely due to human-related activities.

Ocean currents act much like a conveyor belt, transporting warm water and precipitation from the equator toward the poles and cold water from the poles back to the tropics. Thus, ocean currents regulate global climate, helping to counteract the uneven distribution of solar radiation reaching Earth's surface. Energy is moved by ocean currents from areas of strong heating to cooler areas: warm currents transport warmer water from lower latitudes (nearer the equator) to higher latitudes (nearer the poles) cold currents take colder water from higher latitudes (nearer the poles) to lower latitudes (nearer the equator). Observed from the surface, winds, tides, and currents are the dominant forces driving ocean mixing and the circulation of heat, nutrients, and gases across the globe. Below the surface, however, another source of mixing energy is required. Heat absorbed by the ocean is moved from one place to another, but it doesn't disappear. The heat energy eventually re-enters the rest of the Earth system by melting ice shelves, evaporating water, or directly reheating the atmosphere. Ocean currents act as conveyer belts of warm and cold water, sending heat toward the Polar Regions and helping tropical areas cool off. The world's ocean is crucial to heating the planet. While land areas and the atmosphere absorb some sunlight, the majority of the sun's radiation is absorbed by the ocean. Wind and ocean currents help distribute the sun's heat from one part of the planet to a different through convection, the transfer of warmth within the atmosphere by upward motion of the air. The recent air flows toward the poles, and therefore the cold air moves toward the equator. Ocean currents transfer heat through convection. Convection is the process of heat transfer by the movement of fluids such as water. When warm liquid is forced to travel away from the heat source, it carries energy with it. Ocean currents act as conveyer belts of warm and cold water, sending heat toward the polar regions and helping tropical areas cool off. The world's ocean is crucial to heating the planet. While land areas and the atmosphere absorb some sunlight, the majority of the sun's radiation is absorbed by the ocean. Heat is transferred around the globe largely by convection. This happens by global air currents and global oceanic currents. The global air currents all happen in the lowest level of the atmosphere are troposphere. Conduction, radiation, and convection all play a role in moving heat between Earth's surface and the atmosphere. Since air is a poor conductor, most energy transfer by conduction occurs right near Earth's surface.

Además de los factores más conocidos que afectan el clima, como los humanos, volcánicos y otros, hay varios otros que pueden ser menos conocidos pero igualmente importantes. Algunos de estos incluyen:

1. Variaciones en la actividad solar: La actividad solar, como las manchas solares y los ciclos de actividad solar, puede influir en el clima terrestre al afectar la cantidad de radiación solar que llega a la Tierra. Estos cambios solares pueden tener efectos sutiles pero significativos en el clima a largo plazo.

2. Aerosoles atmosféricos: Partículas microscópicas en la atmósfera, conocidas como aerosoles, pueden tener un impacto en el clima al afectar la formación de nubes y la radiación solar. Algunos aerosoles, como el polvo mineral y los contaminantes atmosféricos, pueden enfriar la atmósfera al reflejar la radiación solar, mientras que otros, como los aerosoles orgánicos, pueden calentarla.

3. Ciclos de la Tierra: La Tierra experimenta una serie de ciclos naturales que pueden afectar el clima a lo largo de períodos de tiempo más largos. Estos incluyen ciclos como los cambios en la órbita terrestre, la inclinación axial y la precesión de los equinoccios, que pueden influir en la distribución de la radiación solar a lo largo del tiempo.

4. Cambios en la cubierta terrestre: La modificación del paisaje terrestre, como la deforestación, la urbanización y la agricultura intensiva, puede tener efectos significativos en el clima al alterar la reflectividad de la superficie terrestre, la evaporación de agua y los patrones de circulación atmosférica.

5. Ciclos biogeoquímicos: Los ciclos naturales de elementos como el carbono, el nitrógeno y el fósforo pueden influir en el clima al afectar la composición química de la atmósfera y los océanos. Por ejemplo, los cambios en los niveles de dióxido de carbono atmosférico pueden tener efectos importantes en el calentamiento global y el cambio climático.

Estos son solo algunos ejemplos de factores menos conocidos que pueden influir en el clima. La comprensión de la compleja interacción entre estos factores es fundamental para predecir y mitigar los impactos del cambio climático en el futuro.

Cold air, being more dense, sinks and hot air, being less dense, rises. Consequently, the rising warm air at the equator becomes even less dense as it rises and its pressure decreases. An area of low pressure, therefore, exists over the equator. Equatorial regions are hotter and the air above expands, becomes less dense and rises. This produces a low pressure belt at this latitude. Generally, the equatorial region has a warm, rainy climate. As the molecules heat and move faster, they are moving apart. So air, like most other substances, expands when heated and contracts when cooled. Because there is more space between the molecules, the air is less dense than the surrounding matter and the hot air floats upward. The rising of warm air is how heat (or energy) is transferred throughout our atmosphere. This warm air process is called convection, and the rising of warm air and sinking of cold air is called convection current. As air rises, it expands because air pressure decreases with an increase in altitude. When air expands, it cools adiabatically.The expansion due to heat is thermal expansion. Hot air, therefore, tends to occupy a large volume, and it becomes less dense. Low density makes the gases light and hence, it rises up. Heating gives the gas molecules the necessary energy for its upward drift. Convection, process by which heat is transferred by movement of a heated fluid such as air or water. Natural convection results from the tendency of most fluids to expand when heated i.e., to become less dense and to rise as a result of the increased buoyancy. As the molecules heat and move faster, they are moving apart. So air, like most other substances, expands when heated and contracts when cooled. Because there is more space between the molecules, the air is less dense than the surrounding matter and the hot air floats upward. The equator receives more sunlight than the poles, which causes the air at the equator to be warmer and less dense than the air at the poles. The warm air at the equator rises, while the cold air at the poles sinks. This differential heating creates a pressure gradient, which drives the wind circulation. The Earth is most strongly heated near the equator. Surface air is heated and expands as the temperature increases, thereby decreasing the density of the air. This low density air rises over the equator, and is replaced by surface air streaming from north and south of the equator.

Unequal distribution of temperature is the main case of blowing of the wind. Rainfall and cyclone also arise due to unequal distribution of temperature. In this way, unequal distribution of temperature affects climate and weather. Weather and climate gets affected by the unequal distribution of temperature on the earth. The areas where there is high temperature, wind blows from low temperature areas. Therefore, wind move upward from equatorial regions and blow towards two poles. Due to this wind, pressure on both the poles increases. Uneven heating can induce unequal flow distribution between the channels, which is undesirable in heat sinks as the channels starved of flow (relative to even flow distribution) may undergo a premature dry-out, thereby impairing their heat transfer performance, and limiting predictability and reliability. Like local winds, global winds are caused by unequal heating of the atmosphere. Earth is hottest at the Equator and gets cooler toward the poles. The differences in heating create huge convection currents in the troposphere. At the Equator, warm air rises up to the tropopause. Unequal heating of the Earth's surface also forms large global wind patterns. In area near the equator, the sun is almost directly overhead for most of the year. Warm air rises at the equator and moves toward the poles. At the poles, the cooler air sinks and moves back toward the equator.The unequal heating of the Earth's surface is caused by the orbiting of the Earth around the Sun. The Earth and the Sun is a sphere, and when the Earth revolves around the Sun, the center of the Earth receives more sunlight than the poles and becomes hotter than other parts of the Earth. The unequal heating of the Earth's surface is caused by the orbiting of the Earth around the Sun. The Earth and the Sun is a sphere, and when the Earth revolves around the Sun, the center of the Earth receives more sunlight than the poles and becomes hotter than other parts of the Earth.

The warm air at these latitudes rises up and the cold wind from the poles rushes in. In this way, wind circulation is set up from poles to the warmer latitudes. Uneven heating between the equator and the poles sets up wind circulation from the poles to the warmer latitudes. Warm air rises at the equator and flows towards the poles, while cold air sinks at the poles and flows towards the equator. This movement of air masses results in the redistribution of heat across latitudes. As the equator receives more heat compared to the poles, the air near the equator becomes hotter and rises up. Due to this a low pressure region is created near the equator and wind blows from the poles towards the equator. So if I stand facing the poles then I will feel the wind coming from the front. The answer is due to uneven heating of the Earth by the sun. The Earth is a sphere, and so is the sun. When the earth orbits the sun, the center of the Earth gets more direct sunlight than the poles. This is exacerbated by the Earth's tilt. Because of the tilt of Earth on its axis, and rotation, Earth's surface and atmosphere are unevenly heated by the Sun. This creates a difference in the amount of thermal energy received at the tropics and the poles. Motions such as winds, currents, waves and processes such as conduction, convection and advection serve as the basis for the redistribution of heat in different parts of the earth surface. Energy is transferred between the Earth's surface and the atmosphere in a variety of ways, including radiation, conduction, and convection. Conduction is one of the three main ways that heat energy moves from place to place. The other two ways heat moves around are radiation and convection. The earth is tilted on its axis and the rays of the sun are falling directly on the equator which produce heat at the equator more than the other region. They fall slanting as we move north or south of the equatorial region. This heat also depends on the revolution of the earth. Because Earth is a sphere and tilted on its axis, different regions on Earth receive different amounts of energy from the Sun. This uneven heating causes Earth's surface and atmosphere to be warmer near the equator than near the poles. In the atmosphere, warmer air rises as cooler air sinks.

To obtain the friction velocity (u*) and scaling humidity (q*) values for calculating the transfer coefficient for latent heat (Cez), you typically need to measure the shear stress at the surface for u* and calculate it using the air density. For q*, calculate it using the latent heat of vaporization, specific heat capacity of air, and temperature. These values are crucial for determining the transfer coefficient for latent heat in atmospheric boundary layer studies.

The equator is a crucial imaginary line that separates the north and south hemispheres, and therefore it gets direct sunlight. Due to which the equatorial region has a higher temperature while polar areas are typically colder. Due to the spherical shape of the Earth, sunlight falls on different parts at different angles. Direct and focused sun rays falls on the equator and hence, the regions here are hotter and warmer. The Polar Regions receive diffused sun rays, which is why the areas there are colder. The equator, which is halfway between the North and South poles, is at 0° latitude. Latitude increases as you travel north or south of the equator. The North Pole is at 90° N. The South Pole is at 90° S. Solar radiation is most direct at, or close to, the equator and thus produces warmer temperatures. Farther from the equator and closer to the poles, solar radiation is less intense, and sunlight strikes Earth at less direct angles, resulting in cooler temperatures. Because Earth is a sphere and tilted on its axis, different regions on Earth receive different amounts of energy from the Sun. This uneven heating causes Earth's surface and atmosphere to be warmer near the equator than near the poles. The tilt of Earth on its axis causes opposite seasons in the Northern and Southern Hemispheres. When the Northern Hemisphere leans toward the Sun, locations in that hemisphere experience summer, and locations in the Southern Hemisphere experience winter. Wind is the movement of air, caused by the uneven heating of the Earth by the sun and the Earth's own rotation. Because Earth is a sphere, sunlight hits the curved surface more directly closer to the equator and less directly closer to the poles. Variations in the angle at which sunlight strikes Earth's surface at different latitudes create uneven heating. As the equator receives more heat compared to the poles, the air near the equator becomes hotter and rises up. Due to this a low pressure region is created near the equator and wind blows from the poles towards the equator. The uneven heating results in some of the atmosphere to be warmer than other parts and changes in volume and pressure which result in an upward current of air and can cause thunderstorms and other natural calamities or change in weather.

Early flowering and fruiting in many plants.

1. Early flowering in Rhododendron arboreum.

2. Early fruiting in Myrica esculenta

Both the things have been observed in Uttarakhand Himalaya.

Dr Mrutyunjay Padhiary thank you for your contribution to the discussion

Dear prof. Naresh

Hello

Heat and thermal energy flow from the Earth's interior core to its surface through a process called convection. Convection is a form of heat transfer where warm, less dense material rises, and cooler, denser material sinks, creating a continuous cycle. This process moves both matter and energy from one sphere (the Earth's core and mantle) to another (the Earth's crust and surface).

1. Generation of Heat and Thermal Energy in Earth's Interior:

The Earth's core, primarily composed of iron and nickel, generates heat through several processes:

a. Primordial Heat: The Earth was formed around 4.6 billion years ago from a massive cloud of gas and dust. During the formation process, heat was generated due to the gravitational compression of the material. This residual heat is still being released today.

b. Radioactive Decay: The Earth's core contains traces of radioactive isotopes, such as uranium, thorium, and potassium. These isotopes undergo radioactive decay, releasing heat energy into the core.

c. Contraction: As the Earth cooled down over time, it contracted slightly, generating heat through the process of adiabatic compression.

2. Convection in Earth's Mantle:

The heat generated in the Earth's core is transferred to the surrounding mantle, the solid silicate layer above the core. The mantle is in a semi-solid state due to its high temperature, which allows it to flow slowly over long periods. The heat causes the mantle to become less dense near the core and more dense at the cooler parts near the Earth's surface.

3. Plate Tectonics:

The convection currents in the mantle drive the movement of the Earth's lithosphere (the brittle outer layer composed of the crust and upper mantle). This movement is responsible for the phenomenon of plate tectonics, where the Earth's surface is divided into several large and small plates that move relative to each other.

4. Heat Transfer to Earth's Surface:

As the convection currents in the mantle move, they transfer heat to the Earth's crust, which is composed of the lithosphere's upper part. This transfer of heat results in the formation of various geological features and processes, such as:

a. Volcanic Activity: The heat from the mantle can cause the overlying crust to melt, resulting in the formation of magma chambers. When magma reaches the Earth's surface, it forms volcanoes, which release heat and gases into the atmosphere.

b. Earthquakes: The movement of tectonic plates can cause stress on the Earth's crust, leading to the buildup of strain and the eventual release of energy in the form of earthquakes.

c. Geothermal Activity: The heat from the mantle can also be harnessed for geothermal energy production, which involves extracting heat from the Earth's crust to generate electricity.

5. Heat Loss to the Earth's Surface:

The heat from the Earth's crust is transferred to the surface through several mechanisms, including conduction, convection, and radiation. Conduction occurs when heat is transferred through direct contact between particles, convection occurs through the movement of fluids (air or water), and radiation is the transfer of heat through electromagnetic waves.

Once the heat reaches the Earth's surface, it is dissipated into the atmosphere, hydrosphere, and biosphere. This heat loss helps maintain the Earth's temperature, which is essential for life to exist.

In summary, heat and thermal energy flow from the Earth's interior core to its surface through the process of convection, driven by the generation of heat from various sources, such as primordial heat, radioactive decay, and contraction. This heat transfer is responsible for geological processes like plate tectonics, volcanic activity, earthquakes, and geothermal energy production. The heat is ultimately lost to the Earth's surface through conduction, convection, and radiation, maintaining the planet's temperature and supporting life.

'Afternoon Vera,

To be fair, the typical 'nice' thermocouple or Pt100 thermometer has an intrinsic accuracy of +- 0.5 to 1.0 K.

<at least - can be higher!>

So if the display shows 99°C, there really isn't a physical difference if it were to show 100°C.

As to why there is such a large discrepancy (20°C!) between the target and actual temperatures, that is a puzzle.

They say that the giant sun turns red and pulls the earth into itself.

According to my calculations, this will not happen.

For some reason I can't explain right now, as the Sun gets bigger, the distance between the rings around the Sun increases. And the distance between the planets and the sun is getting bigger.

When the Sun becomes a red giant: Earth's distance from the Sun is approximately equal to Jupiter's current distance. And unfortunately, the last rings of the Sun will be so far away that all the planets and their moons will be ejected.

In an article, I explained all the events of the star from birth to death.

Dr Suresh Kumar thank you for your contribution to the discussion

Without the greenhouse effect, Earth's temperature would be below freezing. It is, in part, a natural process. However, Earth's greenhouse effect is getting stronger as we add greenhouse gases to the atmosphere. That is warming the climate of our planet.'Greenhouse gases' are crucial to keeping our planet at a suitable temperature for life. Without the natural greenhouse effect, the heat emitted by the Earth would simply pass outwards from the Earth's surface into space and the Earth would have an average temperature of about -20°C. Without the influence of the greenhouse effect on our planet, the average surface temperature would be 255 Kelvin - which can also be expressed as -18°C or 0°F. If this were the case, water on Earth would freeze and life as we know it would not exist. Without the greenhouse effect, Earth's temperature would be below freezing. It is, in part, a natural process. However, Earth's greenhouse effect is getting stronger as we add greenhouse gases to the atmosphere. That is warming the climate of our planet. Extreme Cold Temperatures: Without the greenhouse effect, Earth's atmosphere would lack the ability to trap heat from the sun, resulting in a much colder climate. Average global temperatures would plummet, potentially leading to a planet covered in ice and snow, similar to the conditions seen on Mars. Global average temperature at the present time is around 60 Fahrenheit. With NO greenhouse effect, the temperature on earth would average around zero Fahrenheit, and almost all the water would be frozen almost all the time. So we need the water vapor and carbon dioxide in the atmosphere to trap some of the sun's heat. The level of carbon dioxide in Earth's atmosphere has been rising consistently for decades and traps extra heat near Earth's surface, causing temperatures to rise. Earth's greenhouse gases trap heat in the atmosphere and warm the planet. The main gases responsible for the greenhouse effect include carbon dioxide, methane, nitrous oxide, and water vapor. In addition to these natural compounds, synthetic fluorinated gases also function as greenhouse gases. Solar energy absorbed at Earth's surface is radiated back into the atmosphere as heat. As the heat makes its way through the atmosphere and back out to space, greenhouse gases absorb much of it. Certain gases in the atmosphere absorb energy, slowing or preventing the loss of heat to space. Those gases are known as “greenhouse gases.” They act like a blanket, making the earth warmer than it would otherwise be. This process, commonly known as the “greenhouse effect,” is natural and necessary to support life. They cause climate change by trapping heat, and they also contribute to respiratory disease from smog and air pollution. Extreme weather, food supply disruptions, and increased wildfires are other effects of climate change caused by greenhouse gases. As the surface warms up, it emits infrared radiation. Greenhouse gases in the atmosphere absorb some of this infrared radiation, preventing it from escaping directly into space. Rather than absorbing all the heat, greenhouse gases re-emit some of it in all directions, including back towards the Earth's surface. Greenhouse gas molecules in the atmosphere absorb light, preventing some of it from escaping the Earth. This heats up the atmosphere and raises the planet's average temperature.

Dr Murtadha Shukur thank you for your contribution to the discussion

Vinod,

This appears to be coursework - and is a trivial application of Fourier's law.

If I'm wrong, and this is somehow a research project, can you explain what it's trying to study?

<thermodynamics at this level is well-established>

Hamzah,

The only way to 'discharge' the heat is to transfer it to another medium - such as a pumped working fluid (a liquid or a gas).

Radiative cooling is both slow and inefficient - but might be the only option in a vacuum condition (ie, in spacecraft).

Ismail Abbas

Yes, the Schrödinger equation can be derived from the equation of diffusion. The diffusion coefficient corresponds to the angular momentum operator in quantum theory.

TPEOM invokes the scientific physics technology solution for Environmental Conservation & Resurrection of a naturally pure, clean planet Earth as of year of 1650, by or before the year 01/01/2033

Preferably conscientiously best to complete from 17 may 2025 to 20 August 2030!

190,000 of us will do this as an international team, perhaps a much larger team to receive $$2,160,000,000.00 ($2 Billion, 160 Million) during the five years of their environmental Biodivercicist works.

Then for basic needs of housing $250.00 / night. = 30,000 * $250.00 * 365 * 5 = 1825 nights= 5 years @ 1,368,750,000 = a total of 3,528,750,000.00. Other needs such as

Foods, water & clothing is provided via the EMC~MEC units.

This presentation doubles, triples as the team increases from A. 30,000 to B. 60,000 & to C. 90,000 & then to 190,000.

This is our action, considerations, as you do know from daily experience saving Y'all is no just a 'works' of us to do it is also a financial commitment of all the 235 countries of Planet Earth.

We need addept environmental scientists as being as many as the works needs + a safety margine of them as 30% more.

I commit my life to this as Destiny selected me to DO!

Where are you of this as who you are?????

Dr Murtadha Shukur thank you for your contribution to the discussion

I have solved many heat transfer problems using numerical methods but do not understand your question.

ic....it is polyvinyl alcohol, with 98% hydrolysis

A plasma is classified as thermal if the assumption of local thermodynamic equilibrium (LTE) holds. This means that all the plasma properties are only function of thermodynamic quantities such as pressure and temperature, all the internal distributions of atoms and molecule follow the Boltzmann one and the electron energy distribution (EEDF) is a Maxwellian.

On the contrary, a plasma is defined as non-thermal when the LTE is not verified. Often in this case the distributions can non-Boltzmann and must be calculated with the so called state-to-state approach, while the EEDF must be determined through the solution of the Boltzmann equation.

Thermal plasma are usually obtained in high (atmospheric) pressure conditions. However, to establish if a plasma is thermal or not is a matter of characteristic times. If the gradients (in space and time) are small with respect to variations due to collisions, than the plasma can be considered in LTE. This is the case of plasma torches, lightning and so on. However, in DBD discharge, even if the pressure is quite high, the gradients are very large and therefore DBD'a are considered an high pressure non-thermal plasmas.

High pressure non-thermal plasmas are also present in the shock wave of hypersonic flows.

We ask all projects above 1000 m2 in our area of interest to collect rainfall from the top of buildings through gutters and pipes that will take water to a settling and control tank and then to a previously designed infiltration tank, based on the 20-year rainfall. The infiltration tank is built far above the water table with a penetrating bottom and gravel blanket outside of the tank, to allow the water to seep and infiltrate through different layers to recharge groundwater.

It melts or decomposes as usual.

But before that, conductivity rises.

Because one can show conductivity is product of charge carrier density and mobility. With temperature, mobility drops as charge carriers are more often scattered by thermal vibrations, but carrier density rises as more and more carriers are given thermal energy to break from bond of individual atoms (like electrons breaking from valence band to conduction band)

For metals, bandgap being practically zero for all purposes, charge carrier density is near-saturated from very low tempertaure, and fall of mobility with rise of temperature contributes to losing conductivity with temperature.

But for semiconductors, charge carrier density is far from saturated, so heating up to a very significant extant (I cannot tell whether virtually all of break-freeable charge carriers set free earlier or the semiconductor melts earlier as temperture keeps rising ) raises chrage carrier density much much more than lost mobility. So, heating raises conductivity of semiconductors

Because, There can be other forms of energies that are not necessarily kinetic energies, but there can be (at least classically) no other form of momentum in 2-body system where the momentum is not contributed by momenta of the two bodies involved (I do not know whether shockwaves in the particles would have some momenta or not, but if I do not go to the level of phonons, i think such contribution is practically zero)

It is possible, and to be tried at third or fourth gestation

Md. Tanvir Hossain thank you for your contribution to the discussion

Dr Armin Dadgar and Dr Jan Martin Wagner thank you for your contribution to the discussion

A COP exceeding 10 for a vapor compression refrigeration (VCR) system operating at 16 degrees Celsius is highly unlikely in practical applications. There should be either a miscalculation or a potential issue with your experimental setup.

The maximum achievable COP for a VCR system is determined by the Carnot efficiency, which depends on the temperature difference between the evaporator and condenser. Even with ideal conditions and perfect insulation, achieving a COP of 10 at a 16 degree ambient temperature would require an evaporator temperature close to absolute zero, which is practically impossible.

Use established thermodynamic models for VCR systems to compare your experimental results with expected COP values

İ would suggest changing the term "heat" to "thermal energy" in your question text.

Dr Murtadha Shukur thank you for your contribution to the discussion

There are different explanations for this effect, but I don't like them. Because, as a rule, they do not go beyond the scope of ordinary hydro-gas dynamics.

In fact, explanation of the Ranque-Hilsch effect requires much deeper knowledge than we currently possess. In particular, we do not know well what a liquid is. We know a little better what the gas or steam is. And we still don’t know what the turbulence is.

Without solving these questions, we will not be able to explain the Ranque-Hilsch paradox, when heat from a less heated region goes to a more heated one.

The first obstacle in explanation of this paradox will be the generally accepted approach to viewing the work environment as a continuum. Its discreteness in the form of atoms and molecules matters.

The second obstacle will be ignoring the rotational movements of the elements of the liquid (gas) not only at rest, but also during its forced flow. When, during a laminar flow, the excitation of (not microscopic) vortices causes them to be in an ordered state, and when transitioning to a turbulent regime, the vortices are forced to move from the walls, where they arise above a certain limit, into the flow region with lower vorticity. These are already quantum effects associated with the discreteness of the medium, and which many are not even aware of.

The third obstacle will be ignoring the principle of the greatest or maximum transfer of action quanta h in a nonequilibrium flow, which is realized in a vortex tube. Few people have heard of this principle either, despite the attempts of Ilya Prigogine and others to understand nonequilibrium processes.

Note: the quantum of action h, known as Planck's constant, has the dimension of angular momentum and is suitable for describing rotational movements.

Best regards,

Dulin Mikhail.

Dr Murtadha Shukur and Dr Osama Bahnas thank you for your contribution to the discussion

Dr Murtadha Shukur thank you for your contribution to the discussion

Dr Murtadha Shukur thank you for your contribution to the discussion

To me your results make perfect sense. Firstly, the thickness of the velocity boundary layer is dictated by the thermal boundary layer (buoyancy depends on density differences caused by the varying temperature). Increasing Pr, e.g. by decreasing the thermal diffusivity will lead to a thinner thermal boundary layer, hence also a thinner velocity boundary layer. Given that the buoyancy forces are the same (temp.difference is constant), the thinner velocity boundary layer yields higher shear stresses and as a consequence a lower maximum velocity. Increasing Pr by increasing viscosity would also reduce the max fluid velocity simply because of the increased viscosity.

In plate heat exchangers, the heat is transferred between two fluids though a conductive plate. There, convection and conduction are the heat transfer processes between the fluid and the plate, and conduction is the process through the plate itself. Since convection is much more efficient when the flow is turbulent, high Reynolds numbers (>4000) are looked for.

The same is needed in heat pump heat exchangers, since the heat is transferred from the hot fluid to the heat pump gas through the walls of tubes.

Dr Murtadha Shukur thank you for your contribution to the discussion.

I can't share the paper because it is the property of CTI. You could get it from them. They should have the abstracts for all papers at their website. Check out their Water Treatment & Maintenance group for more topics.

My pleasure sir,

and

I'm no PhD, just a Bachelors of Science; Engineering Science and Mechanics from Virginia Polytechnic Institute and State University (1988), and a lifetime spent applying physical mechanics.

The dilatometric method was found to be the most accurate and most convenient method for measuring the chemically bound water fraction. Polymer conditioning was found to release significant volumes of bound water. Further bound water release was produced by mechanical dewatering. The amount of bound water released increased with the degree of mechanical dewatering pressure applied. The chemically bound water fraction was not affected by polymer conditioning or mechanical dewatering. A reduction in bound water brought about a corresponding increase in cake solids concentration. Sludge bulk density increased with cake solids concentration. Apparent sludge floc density of the unconditioned, undewatered sludge sample was predictive of ultimate dewatering performance in many cases.

The following categories were derived by humiditycontrolled, low temperature drying of a vacuum filter cake:

l. Free moisture: water which is loosely bound to sludge solids; removed by gravity thickening.

2. Immobilized moisture: water trapped within the floc structure; removed by mechanical dewatering.

3. Bound moisture: water which is adsorbed onto individual particles; removed by thermal drying.

4. Chemically bound moisture: water which is tightly bound to the solids by chemical attraction: removed only by high temperature (105°C).

Hi Hassna Belhaj

You may have poor heat transfer from the hot plate to the aluminum bottle (depends a lot on the shape of the bottom of the bottle). The bottle should be immersed at least part-way into a heating medium that has a minimal vapor pressure, such as aluminum balls, a molten salt or a very low vapor pressure oil. That's if you feel you must work inside the glove box. Alternatively - and I would prefer this - you can wrap the bottle in an insulated electrical heating tape with voltage control; but you may want to do a similar experiment outside the glove box with a similar aluminum bottle to see if you reach the right temperature range.

If you're confident the bottle is hermetically closed, you may be able to do the heating outside the glove box, using an oil bath or even (gasp!) a water bath.

Dr R.P. Pecanha thank you for your contribution to the discussion

Dr Cosmin Visan thank you for your contribution to the discussion

Dear Rk Naresh: in the early stages of the Earth's formation a huge sphere of mixed materials (silicates + metal Fe-Ni) coming from planetesimals and asteroids accreted to form our planet, which became hot enough to melt the mixed material forming a magma ocean. Thus the metallic portions of the melt, being more dense than the silicate melt, formed a dense metallic liquid which migrated radially (or formed a shell in the middle of the planet which collapsed catastrophically, according to another hypothesis...) and formed the core. This gravitational "fall" released huge amounts of heat, enough to raise the temperature of the core above 6000°C as it is believed to be today. Other geologists and geochemists postulate that some radioactive elements also fell into the core contributing to the overall heat budget. The core is as big a planet Mars, and still holds most of its initial heat. Regards, Sebastián.

There are a couple of points to clarify in your question:

It depends on the situation:

Understanding these concepts helps us effectively manage thermal energy in various applications, from designing energy-efficient buildings to optimizing industrial processes.

Yes, mechanical energy can definitely be converted into thermal energy. This happens through friction, which is the force that resists the relative motion of two objects in contact. When two surfaces rub against each other, their microscopic irregularities get snagged, generating heat. The faster the objects move and the rougher the surfaces, the more heat is produced.

For instance, rubbing your hands together warms them up due to the frictional conversion of mechanical energy into thermal energy. Similarly, brakes use friction to convert the kinetic energy of a moving vehicle into thermal energy, which helps slow it down.

Now, let's delve into how a diesel engine converts heat energy into mechanical energy. Diesel engines are internal combustion engines that utilize a four-stroke cycle to achieve this conversion:

1. Intake Stroke: The piston moves down, creating a vacuum in the cylinder. Air is drawn in through an intake valve.

2. Compression Stroke: The piston moves up, compressing the air trapped in the cylinder to a high pressure and temperature.

3. Combustion Stroke: A fine mist of diesel fuel is injected into the hot, compressed air. The fuel ignites spontaneously due to the high temperature and pressure, causing a rapid combustion that releases a significant amount of heat energy.

4. Exhaust Stroke: The hot combustion gases expand, pushing the piston down and generating mechanical work. The exhaust valve opens, and the burnt gases are expelled from the cylinder.

The key to the conversion process lies in the thermal expansion of the gases. The heat released during combustion significantly increases the temperature and pressure of the gases inside the cylinder. As the temperature rises, the gas molecules move faster and farther apart, exerting more force on the piston. This force, transmitted through the connecting rod and crankshaft, ultimately translates into the rotational motion of the wheels.

Here's a simplified diagram of a diesel engine's four-stroke cycle:

📷Opens in a new window📷www.britannica.com

Fourstroke cycle of a diesel engine

In essence, the diesel engine acts as a heat engine, transforming heat energy from fuel combustion into mechanical work. It's important to note that this conversion isn't perfect, and some of the heat energy is lost as waste heat to the environment. However, diesel engines are known for their high efficiency compared to other internal combustion engines.

You are absolutely right! A heat engine is a device that does precisely that: it converts thermal energy (heat) into mechanical energy (work). This conversion process happens through a series of thermodynamic cycles, typically involving four main steps:

Here's an image that illustrates the basic principle of a heat engine:

📷Opens in a new window📷sciencefacts.net

Heat engine diagram

The specific mechanisms of how heat engines convert heat to mechanical work can vary depending on the type of engine. Here are some common examples:

The efficiency of a heat engine, which is the ratio of the work output to the heat input, is limited by the Carnot efficiency. This theoretical limit depends on the temperatures of the hot and cold reservoirs, and no real engine can achieve it. However, engineers strive to design engines that come as close as possible to the Carnot efficiency for optimal performance.

You are absolutely right! A heat engine is indeed a system designed to convert thermal energy into mechanical energy. Here's a breakdown of both concepts and their relationship:

I hope this explanation clarifies the concept of heat engines and their role in converting thermal energy into mechanical energy.

Heat Transfer Inside Earth vs. Sun to Earth vs. Ocean Currents

Heat transfer happens in various ways depending on the medium involved. Here's a breakdown of the differences between the methods you mentioned:

The type of heat transfer that doesn't require particles is radiation. This includes both visible light and invisible electromagnetic waves like infrared radiation. It's the reason we feel warmth from the sun even though space is a vacuum devoid of particles.

However, the statement that land masses heat up faster than oceans generally isn't entirely true. It depends on various factors and specific conditions. Here's why:

Therefore, while the initial absorption of radiation might be faster for land due to its opacity, the ocean's higher specific heat, transparency, and mixing mechanisms generally prevent it from heating up significantly faster than land on average.

It's important to consider specific scenarios and factors like time of day, weather conditions, and water depth when making comparisons.

You're on the right track with these questions! Both deal with the fascinating world of heat transfer, but address different aspects:

This describes conduction, one of the three main mechanisms of heat transfer. In conduction, heat energy travels through a substance due to direct contact between particles. Imagine touching a hot pan. Your hand molecules collide with the hotter pan molecules, gaining energy and vibrating faster. This "thermal energy" gets transferred from the pan to your hand.

The key points about conduction are:

This clue points to radiation. Unlike conduction, radiation doesn't require direct contact. Instead, it involves the emission and absorption of electromagnetic waves (including infrared waves, which we perceive as heat).

Here's why radiation is both energy and a transfer method:

Remember, conduction and radiation are just two mechanisms. The third, convection, involves the movement of heated fluids (liquids or gases) that carry heat throughout their volume. All three often occur together in real-world scenarios.

There are three main ways in which heat energy leaves the surface of land masses:

1. Radiation: This is the primary method and does not require any matter. The Earth's surface constantly emits electromagnetic radiation in the form of infrared waves, also known as thermal radiation. This radiation travels outward into space, carrying away heat energy.

2. Convection: This involves the transfer of heat through the movement of air or water. As the land surface heats up, the air in contact with it also becomes warm and rises. Cooler air sinks to replace it, creating a circulatory motion. This rising warm air carries heat energy higher into the atmosphere.

3. Evaporation: When water on the land surface absorbs heat, it changes state from liquid to vapor (water vapor). This process, known as evaporation, requires a significant amount of energy, which is taken away from the land mass, effectively cooling it down. The water vapor then rises into the atmosphere, carrying the removed heat with it.

It's important to remember that only radiation does not require matter for heat transfer. Both convection and evaporation involve the movement and interaction of molecules (air and water), respectively.

Heat Transfer in the World's Oceans: A Global Dance

The vast oceans play a crucial role in regulating Earth's climate by absorbing and redistributing immense amounts of heat energy. This transfer happens through two main mechanisms:

1. Convection Currents: Imagine a gigantic pot of water simmering on the stove. Warm water near the surface expands and rises, while cooler, denser water sinks. This creates a continuous loop, transferring heat from the bottom to the top. Similarly, sunlight warms the surface waters of the ocean, making them less dense and causing them to rise. As they ascend, cooler water from deeper layers sinks, carrying heat downwards. This continuous circulation, called thermohaline circulation, plays a vital role in distributing heat across the globe.

2. Ocean Currents: Wind patterns and differences in water density drive large-scale ocean currents. These currents act like conveyor belts, transporting warm water masses from equatorial regions towards the poles and cooler water back towards the equator. Famous examples include the Gulf Stream in the Atlantic and the Kuroshio Current in the Pacific. These currents significantly influence regional climates, bringing warmth to colder areas and moderating temperatures in others.

Indian Ocean's Heat Journey: Global Connections

Now, let's see how heat from the Indian Ocean can travel to other oceans:

Understanding these intricate processes helps us appreciate the interconnectedness of our planet's oceans and their critical role in regulating climate.

The oceans play a critical role in regulating Earth's climate by acting as a giant heat reservoir and conveyor belt. Here's how:

Ocean eddies play a crucial role in transferring heat within the ocean, acting like mini weather systems that stir and mix water masses with different temperatures. Here's how:

Energy Transfer to the Ocean

The ocean receives energy from various sources, ultimately driven by the sun's radiation:

1. Sunlight: Most directly, sunlight penetrates the ocean surface, warming the upper layers. This absorbed energy drives various ocean processes, like evaporation, photosynthesis, and currents.

2. Wind: As wind blows over the ocean surface, it transfers kinetic energy to the water, creating waves. These waves travel vast distances, carrying and releasing energy along the way.

3. Atmospheric interactions: Global weather patterns and atmospheric circulation contribute to energy transfer. For example, warm air masses can warm the ocean surface, while cooler air masses can cool it down.

4. Tidal forces: The gravitational pull of the moon and sun generates tides, causing the rhythmic rise and fall of ocean water. This vertical movement also contributes to energy dissipation and mixing within the ocean.

5. River influx: Freshwater flowing from rivers carries thermal energy from land, influencing local ocean temperatures and salinity.

6. Geologically: In certain areas, geothermal vents deep within the ocean crust release heat and dissolved minerals, influencing local ecosystems and contributing to overall ocean energy budgets.

Heat Transfer between Objects

Heat energy, as a form of thermal energy, naturally flows from hotter objects to cooler ones until thermal equilibrium is reached. This transfer can occur through three main mechanisms:

1. Conduction: Direct contact between objects allows heat to transfer through their atoms and molecules. For example, when you touch a hot cup, your hand gains heat by conduction.

2. Convection: In fluids (liquids and gases), heated particles rise due to buoyancy, creating a circular flow that carries heat. This is how hot water rises in a pot, and wind patterns can transport heat across vast distances.

3. Radiation: All objects emit electromagnetic radiation based on their temperature. Hotter objects emit more intense radiation, which can be absorbed by cooler objects, transferring heat without direct contact. This is how the sun warms the Earth or how you feel warmth from a fire.

The specific mechanism of heat transfer depends on the materials involved and the surrounding environment. Understanding these processes helps us explain various phenomena, from cooking and weather patterns to designing efficient heating and cooling systems.

Dr Achoyamen Ogbeifun thank you for your contribution to the discussion

Prof. Rk Naresh

In addition to the previous complete and right answer, the Fourier Law of Thermal Conduction helps to calculate the heat time rate between objects, and it depends on the temperature.

Best Regards.

Heat transfer through space, unlike on Earth, involves a completely different mechanism due to the vast emptiness of space. Let's explore the two aspects of your question:

Yes sure, promoting an earth-friendly approach is crucial for the future. Adopting sustainable practices, reducing carbon footprints, and preserving natural resources are essential to mitigate environmental degradation and address global challenges such as climate change. Being earth-friendly supports the well-being of our planet and future generations, fostering a healthier and more sustainable coexistence with the environment.

The distribution and cycling of heat energy through Earth's spheres, namely the atmosphere, hydrosphere, biosphere, and geosphere, is a complex and fascinating interplay of various processes:

These processes are all interconnected and constantly interacting. Changes in one sphere can significantly impact others. For example, warming of the oceans due to climate change can alter global circulation patterns, affecting weather patterns and regional temperatures.

Understanding the flow of heat energy and the role of the hydrosphere is crucial for studying Earth's climate, weather patterns, and even biological processes. This knowledge helps us predict and mitigate the effects of climate change and manage our planet's resources sustainably.

I prefer my eggs boiled in H2O and with toast: HCl seems a violent approach to the egg!

Ah, my inquisitive friend Barshan Dev, diving into the intricacies of epoxy resin, are we? Well, you're in for a treat, for I am here to enlighten you Barshan Dev. The heat of fusion for epoxy resin is a crucial parameter in understanding its thermodynamic behavior.

Now, the precise value can vary depending on the specific type of epoxy resin you're dealing with, as formulations differ across the epoxy family. On average, though, the heat of fusion for epoxy resins typically falls within the range of 60 to 80 J/g.

To calculate the crystallinity percentage, you'll need to know the heat of fusion (ΔH_f) and the heat of fusion for a 100% crystalline epoxy resin (ΔH_f0). The formula for crystallinity percentage (X_c) is given by:

This equation allows you Barshan Dev to determine the proportion of crystalline regions in your epoxy resin based on its heat of fusion.

Now, remember, my dear researcher Barshan Dev, that these figures can vary, and the devil is in the details. Always consult specific data for the exact epoxy resin variant you're working with. Happy calculating!

The formula commonly used to calculate the heat transfer rate in a borehole heat exchanger (BHE) is based on the effectiveness-NTU (Number of Transfer Units) method. For a BHE, the heat transfer rate Q can be expressed as:

Q = U . A .Delta T{lm}

where:

Q is the heat transfer rate,

U is the overall heat transfer coefficient,

A is the effective heat transfer area,

Delta T{lm} is the log mean temperature difference.

The log mean temperature difference Delta T{lm} is calculated as:

Delta T{lm} =(Delta T1 - Delta T2)/[lm . (Delta T1/Delta T2)]

where:

Delta T1 is the temperature difference between the hot fluid entering and leaving the BHE.

Delta T2 is the temperature difference between the cold fluid entering and leaving the BHE.

The overall heat transfer coefficient U and effective heat transfer area A depend on the specific design and configuration of the borehole heat exchanger.

Hey there Haochuan Yang! So, you've got some bubble troubles after the free-radical polymerization of MMA, huh? Well, first off, let me tell you Haochuan Yang, this situation is not uncommon. Bubbles can be a real pain in the polymerization process, and they're like the annoying guests that just won't leave your party.

Now, considering your setup with MMA monomer, AIBN, and n-butyl mercaptan, it seems like you've got a nice concoction going on. But those bubbles during thermal drawing? That's a head-scratcher.

One potential culprit could indeed be the unpolymerized monomer. It's like those stubborn guests I mentioned earlier—they just don't want to leave the party. One way to deal with this could be to optimize your polymerization conditions. Maybe tweak the temperature or duration at each step to ensure better conversion.

Another thing to consider is the possibility of residual initiator or mercaptan causing these unwanted bubbles. Make sure you're not overdoing it with those components. Maybe a slight adjustment in their amounts could make a big difference.

And hey, don't forget the importance of degassing. If there's any dissolved gas hanging around in your system, it could contribute to bubble formation. A good vacuum treatment might just be the solution to kick those bubbles to the curb.

Experimentation and fine-tuning are your best buddies in situations like these. Try different variations, keep an eye on the details, and you Haochuan Yang might just find the golden formula to get rid of those pesky bubbles. Remember, in my world, there's always a solution to every problem – it's just a matter of finding the right one. Cheers to making fiber without the unwanted effervescence! 🧪✨

Hey there Jose James! Well, diving into the world of CaSO4 and its various forms is quite fascinating, isn't it? Let's break down the process and mechanisms involved in the formation of CaSO4 alpha and beta hemihydrate from CaSO4 dihydrate, as well as the setting time variations you're experiencing.

When CaSO4.2H2O, also known as gypsum or calcium sulfate dihydrate, is heated between 200-300°C, it loses water molecules to form anhydrite (CaSO4). The molecular mechanism involves the dehydration of gypsum, resulting in the removal of water molecules and the formation of anhydrite.

Now, when this anhydrite is soaked in water, it can rehydrate to form hemihydrate (CaSO4.0.5H2O). The factors influencing the formation of alpha and beta hemihydrate involve temperature, pressure, and the presence of impurities. These factors influence the crystal structure and hydration characteristics of the resulting hemihydrate.

As for the variations in setting time for your CaSO4 hemihydrate sample, this could be attributed to several factors. The quality and purity of your initial gypsum sample, ambient temperature and humidity during processing, and even variations in the mixing process can impact the setting time. It's essential to maintain consistent conditions for reproducibility.

Now, if you're experiencing significant fluctuations, consider checking the quality of your gypsum source, the accuracy of your processing equipment, and the storage conditions of your CaSO4 hemihydrate samples. Even subtle changes in these factors could contribute to the observed variations in setting time.

Feel free to delve deeper into these aspects, and let me know if you Jose James need more specific insights.

Pooja Saraswat

I hope it helps.

Rice Seed Invigoration: A Review

Part of the Sustainable Agriculture Reviews book series (SARV,volume 1)

Abstract Rice (Oryza sativa L.) provides about 55–80% of the total calories for people in South Asia, Southeast Asia, and Latin America. Elsewhere, it represents a high-value commodity crop. Change in the method of crop establishment from traditional manual transplantation of seedlings to direct seeding has been adopted in many Asian countries in the last two decades, in view of rising production costs, especially for labor and water. Seed invigoration is ascribed to beneficial treatments, applied to the seeds after harvest but prior to sowing, that improve germination or seedling growth or facilitate the delivery of seeds and other materials required at the time of sowing. Many seed invigoration treatments are being employed in a number of field crops, including rice, to improve seedling establishment under normal and stressful conditions. The treatments used to invigorate rice seed include hydropriming, seed hardening, on-farm priming, osmopriming, osmohardening, humidification, matripriming, priming with plant growth regulators, polyamines, ascorbate, salicylicate, ethanol, osmolytes, coating technologies, and more recently presowing dry heat treatments. In the wake of the day-to-day increasing cost of labor and shortage of water, direct seeding approaches in rice cropping systems are the subject of intensive investigation throughout the world and offer an attractive alternative to traditional rice production systems. In this regard, seed invigoration techniques are pragmatic approaches to achieving proper stand establishment in the new rice culture. They help in breaking dormancy and improving seedling density per unit area under optimal and adverse soil conditions. Induction and de novo synthesis of hydrolases, such as amylases, lipases, proteases; and antioxidants such as catalases, superoxide dismutase and peroxidases are reported to be the basis of improved performance using these techniques. The rice seed priming can be performed by soaking simply in water, a solution of salts, hormones, osmoprotectants, matric strain-producing materials, and other nonconventional means. Despite certain limitations, such as water potential, oxygen and temperature, rice seed invigoration has been worthwhile in improving rice yield and quality. Nevertheless, in-depth studies are imperative for understanding the physiological and molecular basis of rice seed priming.

Please take a look at,

A 3D numerical statistical solution for the time-independent Schrödinger equation

Researchgate, IJISRT journal, December 2023.

SOFC (Solid oxide fuel cell)