Questions related to Cold Temperature
How cold air moves from the poles to the equator and how would the air move from equator to poles if the Earth did not rotate?
How does sea ice affect ocean currents and role of ocean currents in heat distribution and effect of cold current water on the continental coastline?
Manuscript Title: Impact of Machining Parameters on Surface Roughness and Machining Forces in Al7075 Turning with MQL and Cold Fluid
People around the world are now nervous and confused about 'Corona Virus' . What are the differences between corona virus induced fever/cold/cough and normal fever/cold/cough ?
For the first rxn, I performed Claisen Schmidt condensation reaction to form an animated- diarylpentadienone product in cold conditions by dissolving aminoacetophenone in ethanol with 6M NaOH as a catalyst and then adding cinnamaldehyde. After an overnight reaction, a yellow product spot was formed on the TLC.
However, the issue begins during the second rxn. For 2nd rxn, sulfonamide-containing diarylpentadienone synthesized via condensation of the equimolar quantity of 4-trifluoromethylbenzene sulfonylchloride and aminated diarylpentadienone in methanol before the addition of pyridine (catalyst). The rxn is not completed after running overnight for 24 hours. According to the TLC, both the starting material (SM) spots and product spots look exactly similar with the same Rf value, showing the rxn does not happen. if the rxn continues longer than 24 hours, the product spot starts to vanish. 1H NMR shows the rxn is not working with some missing H peaks from the second rxn for the sulfonamide compound.
For both rxn 1 & 2:-
8:2 (hexane: ethyl acetate) is used as a mobile phase for TLC.
I have tried TEA as a catalyst replacing pyridine for rnx 2 still the reaction is still not working. I really need help.
Any explanation or suggestions regarding my current issue will be highly appreciated.
Subjective experience in a hot near-desert climate with extremes of hot and cold temperatures during the year
I am trying to figure out the best way to keep a 96-well plate frozen inside an anaerobic chamber. I am currently using a cold plate, sticking it in the -80C freezer, then keeping it all on dry ice until I am ready to take it in the chamber. However, I cannot take dry ice into the chamber, so I bring the 96-well plate on top of the cold plate into the chamber to attempt to keep it frozen. This doesn't work for a very long time before it begins to thaw, so I'm looking for a better solution. Any suggestions?
Why is the top of a mountain cold if it's closer to the sun and relationship between pressure density and height?
Have I taken my area correctly to find the enthalpy of fusion Hm , so here the percentage crystallinty be Hm/Hm0 or i should consider the peak before the melting peak also and use the Hm-Hc/hm0 formula . Is this an example of cold crystallisation ?
I need to add a latent heat flux of evaporation to the hot side boundary, which is a function of the pressure difference between the cold side and the hot side boundary.However, the pressure at the cold side boundary is a function of temperature. How does it apply to the hold side? How can I solve this problem?
What causes the winds to curve as air travels from warm areas to cold areas and western coast of India receive very high rainfall in summer mainly?
Are temperatures changing in Polar Regions faster than other regions of the planet and why there is snowfall in cold countries instead of rainfall?
We synthesized a peptide made up of 7 amino acids. After cleaving the peptide with TFA, we tried to precipitate the peptide from cold ether. However, it seems like our peptide is somehow soluble in ether. Are there any other organic solvents to precipitate peptides?
How do divergence and convergence each affect wind speed and in which part of the Earth where warm air converges to cold air that causes circulation?
I'm trying to obtain xylose crystals from the aqueous phase of an acid hydrolysis-derived process. After evaporating the water, we performed an ethanol extraction in cold. It was supposed to yield xylose crystals, but I had none. Would any of you recommend a different protocol?
We have a fisherbrand powerbank (cat. FB300Q) that we use for our western blots. During the transfer, we noticed that it would not reach 90 volts and only get up to 77 volts. We thought it might have been the electrodes, so we switched out the cassette and lid, but unfortunately, that didn't resolve the issue. We also thought it might not be cold enough, so we put a fresh ice pack in the chamber, but that didn't work as well. Also, in the past, we used to put our transfers in the cold room (large walk-in 4C) and sometimes the power banks would switch from volts to amps.
Has anyone else ever experienced this during a transfer? Could this problem be mechanical, or something else?
Thanks for all your help!
1. Explain how dew, frozen dew, and frost are visible.
2. Vary between cold fog, humid wet, and fog.
3. When the relative humidity of the air is less than 100 percent, can it form fog?
4. Name and description of four types of fog.
5. Why do winter fogs usually "burn off" in the late afternoon?
6. As many positive consequences of fog as you can.
7. List and describe the three methods of fog dispersion?
8. How is a radiation element normally formed?
9. Are the atmospheric conditions necessary for the development of fog mixture?
10. How does evaporation (mixing) fog form?
11. Clouds are more generally classified from the height above the ground, the surface is a list of large values of height and cloud types
List associated with each
12. List at least two recognizable features from each of the ten lower clouds
13. Why are clouds usually thin? Why are they almost entirely composed of ice crystals?
14. How can you tell Altostratus from cirrostratus?
Snow accumulation on road surfaces will turn into ice by over-passing traffic, especially heavy traffic. Ice will move by a small amount every time a vehicle passes. Why will it end up in pointed, thorn-like peaks?
what are the parameters to check or consider when select a bonding agent for old concrete with fresh concrete or apply to avoid cold joints when a continuous concrete pouring for raft or Silo.
I am using cell heater that heat only the curved survace of the cell so cold spots are observed on the flat surface. How can I remove it?
I am looking for this publication:
G. J. Ranque, “Experiments on Expansion in a Vortex with Simultaneous Exhaust of Hot and Cold Air,” Le Journal De Physique et le Radium (Paris), Vol. 4, 1933, pp. 112-114.
Unfortunately I can not find it.
Which part of India has hot summer and very cold winter and why is the seasonal temperature range less in the coastal region than it is in the interior of the continent?
Why are places near the sea neither very hot nor very cold andplaces near the sea are cooler in summer and warmer in winter than places inland?
What are the control affecting the climate of India andreasons for excessive cold in North India during winters as compared to the peninsular region?
Why the places near the sea usually have temperature that remains fairly constant throughout the year and desert very hot during the day and very cold during the night?
Why the weather in coastal areas is not as cold as in other regions in winter and why water in the sea is cold during day and warm during night?
What are the main reasons for excessive cold in North India during winters as compared to the peninsular region and does climate change affect coastal areas in India?
Why does the hot water rise and mix with the cold water but the cold water does not rise and mix with the hot water?
What happens when two liquids of different temperatures are mixed and when two cups of cold water of the same temperature are mixed the water will be twice as cold?
Which kind of rock transforms because of hotness or coldness and pressure and what rock type is formed from the slow cooling of magma under the Earth's surface?
What is the breaking of rocks by heat rain cold and wind and process of breaking rock into small pieces without changing the composition of the rock?
How does cold temperature affect rocks and how does the freezing and melting action of water affect a rock?
I tried using ChatGPT for the first time...thought maybe it could provide something different than what I planned. I think it is giving really wrong information. Wouldn't using acetone precipitate macromolecules (and not small metabolites)?
I asked for a method to separate small metabolites from a cell lysis, ChatGPT replied with.....
Certainly! Here's a simple procedure that you could use for yeast lysis and crude purification of small metabolites:
- Grow the yeast cells to the desired density and harvest them by centrifugation.
- Wash the cells with cold distilled water and then resuspend them in a buffer solution containing 50 mM Tris-HCl (pH 8.0), 1 mM EDTA, 1 mM DTT, and 1 mM PMSF.
- Lyse the cells by mechanical means such as bead beating or sonication. Be sure to keep the samples cold during this step to avoid protein denaturation.
- Centrifuge the lysate at 10,000 g for 10 minutes to remove the cell debris and large organelles.
- Collect the supernatant and add 3 volumes of cold acetone to precipitate the small metabolites. Mix well and incubate at -20°C for 1 hour.
- Centrifuge the samples at 10,000 g for 10 minutes to pellet the precipitated metabolites.
- Discard the supernatant and wash the pellet with cold acetone to remove any remaining proteins.
- Air dry the pellet and resuspend it in a suitable
I'm sure ChatGPT can be very convenient, and I've heard it can be used to develop protocols etc., but I'm not convinced.
Does chemical weathering occur fastest in cold or dry climate and type of weathering is more active in polar areas why?
Is the rate of chemical weathering faster in hot wet climates than in cold dry climates and weathering is more effective in dry and cold area?
Does chemical weathering occur fastest in cold or dry climates and rate of chemical weathering faster in warm wet climates?
What can be the reason for Himalayan Mountains are very cold and most of the ranges are covered with snow all the time?
Is the rate of chemical weathering faster in hot wet climates than in cold dry climates and chemical weathering happen more slowly?
Why does chemical weathering occur slowly in Polar Regions and types of weathering are slower in cold dry places?
Why is there so much difference in day and night temperature in a desert and weathering is more effective in dry and cold area?
Can bacteria grow in cold environment and organisms that grow at 20°C and have a maximum growth temperature of 30°C called?
What happens to bacteria at 0 degrees and which bacteria survive in extreme cold and organism can live in extremely cold conditions?
Can bacteria survive in extreme very cold and hot environments and microorganisms thrive between low and high temperature?
Why seasons are reversed between northern and Southern Hemisphere and why is it so cold in the Southern Hemisphere during winter?
Which of these is an adaptation to help organisms survive in the cold and type of organisms those grow best at temperatures of 45°C to 70°C?
Why air pressure is more in cold air regions & less in hot regions & why is cold air less dense than warm air & reason why it rises up?
Why is it so cold in the Southern Hemisphere during winter and why is the sun stronger in summer than winter?
How do bacteria survive in cold temperatures and bacteria live in extreme environments and can allows bacteria to survive in extreme environments?
What bacteria can grow at higher temperatures & type of bacteria grows best at moderate temperatures 20° and 45°C which are not too hot & not too cold?
What is the reason behind an early heat wave in north India & reasons for excessive cold in north India during winter & as compared to peninsular region?
Why cold environments are found at high latitudes and which zones of latitude experience the most changes of temperature why?
Why do low latitude areas have a warmer climate & why is climate in low latitude regions mainly hot & sunny but climate in high latitude regions mainly cold?
Where the coldest is place in India and where the coldest recorded place on Earth why is it so cold?
What is low temperature stress in plants and maintain crops in cold weather and does cold temperature affect farming?
I want to know any available article of statistical method to estimate - Human activities (Anthropogenic), which can accelerate snow melting. Please help to find any suitable method to any published article on this topic.
There are several human activities (GHGs emission, CO2 release, urbanization etc.), which resulted massive snow melting now a days. But to quantify the percentage (%) of share coming from Human activities, which causing SCA change.
Thanks in advance.
Email - firstname.lastname@example.org
I've extracted PHA in chloroform using soxchlet extraction method at 65 degree celsius and tried precipitating the dissoloved polymer in cold methanol (70%), but could'nt see any precipitation. I've tried this method many times but not able to see the polymer. Is there a problem with my extraction method or the produced polymer is so low in concentration that I'm not able to get the precipitation.
I use UV and photoinitiator to gel my PEG-acrylate hydrogel. But I observe that when the temperature is lower (at night during winter), it's very easy to get pre-gelled before molding, even without the light. what is the reason behind?
Thanks very much!
I am trying to stimulate Brown Adipose Tissue cells by exposing to cold.
Previous research had shown that in-vivo, the optimal temperature exposure (of the whole organism) is 16°C for at least 2 hours. During the exposure the BAT cells start to to regulate energy expenditure through non-shivering thermogenesis.
I am trying to do it in-vitro.
Any ideas on an optimal temperature exposure?
Thanks in advance,
(1) Effects of cold on human physiological and pathological processes (2) Features of characteristic diseases in cold areas (3) Basic and clinical study of cold stimulation on different diseases (4) Clinical application of Cryotherapy (5) Clinical treatment and basic research of of frostbite (6) Pharmaceutical Research in Cold Regions (7) Sports medicine in Cold Condition (8) Military support
In order to save some energy, one decision our lab is examining would be to increase the temperature limit of the freezers at -70°C instead of -80°C. I guess 10°C difference in this very low temperatures may help to save substantial amount of energy supply. Therefore, we are wondering if samples can be stored at this temperature without causing any remaining molecular activities (oxidative stress and so on).
It is not super clear in the litterature why this threshold of -80°C has been selected, does it result from empirical measures or not?
If anyone has an idea on the reasons for the choice of -80°C, this could help us to take the best decision.
Thanks in advance
I want to produce a part with wet bag cold isostatic press. this part is complicated in terms of dimensions and geometry. till now I have use integrated mold and sealing and demoulding was an issue, but for this part it is different.
I would be grateful if you could guide me.
Normally, the air descending down the side of a mountain heats up and the wind speed decreases. This wind is called Föhn. Schematic link https://atlasprirodirossii.ru/veter-fen-i-ego-sekret-dlya-cheloveka/. Sometimes the foehn turns into a cold mistral wind and its speed increases downhill. This happens only in those places where the lee side of the mountain is very steep. Link to two photos where the mistral occurs https://en.wikipedia.org/wiki/Mont_Ventoux. Most often, such a wind occurs on the coast. In the Black Sea, this is the Novorossiysk mistral (Bora). We conducted a study and found that at the foot of a steep leeward slope of a mountain, when a jet of air is separated from the slope, a "vacuum" is formed. It is associated with a decrease in air temperature and increases the pressure gradient down the mountainside. The temperature can drop from positive to minus 15 degrees. The wind can increase up to 60 m/s. Check out our article file:///C:/Users/User/Downloads/texc_2015_4(1)__7.pdf.