Cold

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"Despite the growing interest in the field of ultracold chemistry, experimental progress has been hampered by a lack of appropriate methods to trap and cool molecules. Laser cooling, while very successful, is limited to a small number of atoms in the Periodic Table because few atoms and no molecules have closed cycling transitions. The main methods to produce cold molecules of chemical interest can be divided into two groups. Buffer gas cooling relies on collisions with cold helium in a dilution refrigerator to cool paramagnetic molecules and trap them in a magnetic trap. Super-sonic expansion is used by other methods to precool the molecules. The resulting cold molecular beams have been slowed and trapped in some experiments by interactions with pulsed electric fields Stark decelerator, by interactions with pulsed optical fields, by spinning the nozzle, and by billiardlike collisions. Finally, laser-cooled alkali-metal atoms are used to produce cold molecules via photoassociation. None of these methods have, to date, achieved the phase space densities required to observe reaction dynamics at ultracold temperatures. We recently demonstrated a general method to stop and eventually trap paramagnetic atoms. Our method is based on the interaction of a paramagnetic particle with pulsed magnetic fields. It operates in analogy with the Stark decelerator by reducing the kinetic energy of a para-magnetic atom passing through a series of pulsed electro-magnetic coils. The amount of kinetic energy removed by each stage is equal to the Zeeman energy shift that the atom experiences at the time the fields are switched off."

- Cold

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"Living in a cold house, apartment, or other building can cause hypothermia. In fact, hypothermia can happen to someone in a nursing home or group facility if the rooms are not kept warm enough. If someone you know is in a group facility, pay attention to the inside temperature and to whether that person is dressed warmly enough. People who are sick may have special problems keeping warm. Do not let it get too cold inside and dress warmly. Even if you keep your temperature between 60°F and 65°F, your home or apartment may not be warm enough to keep you safe. This is a special problem if you live alone because there is no one else to feel the chilliness of the house or notice if you are having symptoms of hypothermia. Here are some tips for keeping warm while you're inside: * Set your heat to at least 68–70°F. To save on heating bills, close off rooms you are not using. Close the vents and shut the doors in these rooms, and keep the basement door closed. Place a rolled towel in front of all doors to keep out drafts. * Make sure your house isn't losing heat through windows. Keep your blinds and curtains closed. If you have gaps around the windows, try using weather stripping or caulk to keep the cold air out. * Dress warmly on cold days even if you are staying in the house. Throw a blanket over your legs. Wear socks and slippers. *When you go to sleep, wear long underwear under your pajamas, and use extra covers. Wear a cap or hat. * Make sure you eat enough food to keep up your weight. If you don't eat well, you might have less fat under your skin. Body fat helps you to stay warm. *Drink alcohol moderately, if at all. Alcoholic drinks can make you lose body heat. *Ask family or friends to check on you during cold weather. If a power outage leaves you without heat, try to stay with a relative or friend. You may be tempted to warm your room with a space heater. But, some space heaters are fire hazards, and others can cause carbon monoxide poisoning. The Consumer Product Safety Commission has information on the use of space heaters."

- Cold

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