b****a
发帖数: 4465 | 1 The following is an actual question given on a University of Washington
chemistry mid-term exam. The answer by one student was so "profound" that
the professor shared it with colleagues, via the Internet, which is, of
course, why we now have the pleasure of enjoying it as well...
Here is the "Bonus Question" on the exam: "Is Hell exothermic or
endothermic ?"
Most of the students wrote proofs of their beliefs using Boyle's Law or
some variant. One student, however, wrote the following:
First, w... 阅读全帖 |
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B******m
发帖数: 2643 | 2 The following is an actual question given on a University of Washington
chemistry mid-term exam. The answer by one student was so "profound" that
the professor shared it with colleagues, via the Internet, which is, of
course, why we now have the pleasure of enjoying it as well...
Here is the "Bonus Question" on the exam: "Is Hell exothermic (gives off
heat) or endothermic (absorbs heat)?"
Most of the students wrote proofs of their beliefs using Boyle's Law (gas
cools when it expands and heats wh... 阅读全帖 |
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n*********7
发帖数: 4682 | 3 THR我给你看看盐酸是怎么治的，稀释小苏打是contraindications!!!!，插胃管过了30
分钟P用没有，因为早被吸收了
Gastric emptying and decontamination
Do not administer emetics because of risks of re-exposure of the
vulnerable mucosa to the caustic agent. This may result in further injury or
perforation.
Gastric lavage by traditional methods using large-bore orogastric Ewald
tubes are contraindicated in both acidic and alkaline ingestions because of
risk of esophageal perforation and tracheal aspiration of stomach contents.
Activat... 阅读全帖 |
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F****y
发帖数: 145 | 4 https://en.wikipedia.org/wiki/Shock_wave
Detonation wave[edit]
Main article: Detonation
A detonation wave is essentially a shock supported by a trailing exothermic
reaction. It involves a wave travelling through a highly combustible or
chemically unstable medium, such as an oxygen-methane mixture or a high
explosive. The chemical reaction of the medium occurs following the shock
wave, and the chemical energy of the reaction drives the wave forward.
A detonation wave follows slightly different ru... 阅读全帖 |
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A********0
发帖数: 2070 | 5 google了一下，品种还不少
发现里面有一种是以前女朋友送过我暖手的
可以重复使用，用完放锅里煮，就又能用了
Heating pads are made of a plastic pouch and a clear liquid. Inside the
pouch is a metal disk that crystallizes the liquid causing it to heat up.
Types of heating pads include electrical, chemical and hot water bottles.
Disposable chemical pads employ a one-time exothermic chemical reaction such
as catalyzed rusting of iron, or dissolving calcium chloride. The reagents
are kept in separate compartments within the pad. When the user squeezes... 阅读全帖 |
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c*****r
发帖数: 529 | 6 http://truthcdm.com/this-could-be-the-end-for-big-oil/
This Could be the End for Big Oil
stunning breakthrough in chemical engineering has unleashed a massive supply
of fuel…
Enough fuel, in fact, to power the entire globe for over 36,000 years.
It’s poised to decimate Big Oil’s obscene profits, make OPEC obsolete, and
hand the United States 100% energy independence.
In fact, the U.S. Department of Defense just invested $7 billion in a single
day…
Apple, Google, and Facebook are spending billion... 阅读全帖 |
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B******1
发帖数: 9094 | 7 Crazyman is a chemist. He could many exothermic reactions at his disposal. |
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M*******n
发帖数: 1165 | 8 是一种基于锆的子弹，单shell就5 USD，而且由于产生后座不足只能在手动action上用
。应该是有些州禁了这种子弹...
Dragon's Breath
Dragon's Breath at night
A Dragon's Breath usually refers to a zirconium-based pyrotechnic shotgun
round. When the round is fired, sparks shoot out to about 5 m (20 feet).[1]
While it has few tactical uses, the visual effect it produces is impressive,
similar to that of a short-ranged flamethrower. The pyrotechnic shell is
expensive compared to other shells, costing around 5 US dollars per shell.
Because it is a very... 阅读全帖 |
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b*********z
发帖数: 1817 | 9 我看了，是假，但是同一个主题下，有这篇比较updated的
http://skepticalteacher.wordpress.com/2011/03/15/japanese-nucle
13.internal contamination not external radiation is the danger said
April 28, 2011 at 11:42 pm
There is a difference between radiation and contamination. Also a difference
between getting a dose of radiation externally (like an xray) and ingesting
radioactive particles which then target specific tissues (eg thyroid, lung,
brain, bone marrow etc depending on the specific element).
Radiation levels from t... 阅读全帖 |
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b*s
发帖数: 82482 | 10 诗人有Poetic license，可以定义名词。
非诗人的燃烧的定义是这样的：
Combustion (play /kmbs.tn/) or burning is the sequence of exothermic
chemical reactions between a fuel and an oxidant accompanied by the
production of heat and conversion of chemical species. The release of heat
can result in the production of light in the form of either glowing or a
flame. Fuels of interest often include organic compounds (especially
hydrocarbons) in the gas, liquid or solid phase.
当然，诗人可以把核反应叫做燃烧，正如Lucas Star Wars里面Death Star爆炸可以有
声音一样.... 阅读全帖 |
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r****a
发帖数: 41 | 11 Here is a nerdy joke, a bit long, and in English. But in the end, it worths
the pain, I think ;)
=============================================================
The following is an actual question given in a University of Washington
chemistry mid term paper. The
answer by one student was so 'profound' that the professor shared it with
colleagues, via the Internet,
which, of course, is why we now have the pleasure of enjoying it as well:
Bonus Question: Is Hell exothermic (gives off heat) or endoth |
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G******U
发帖数: 4211 | 12 Properties of Hydrogen
Hydrogen is a nonmetal. It is placed above group in the periodic table
because it has ns1 electron configuration like the alkali metals. However,
it varies greatly from the alkali metals as it forms cations (H+) more
reluctantly than the other alkali metals. Hydrogen‘s ionization energy is
1312 kJ/mol, while lithium (the alkali metal with the highest ionization
energy) has an ionization energy of 520 kJ/mol.
Because hydrogen is a nonmetal and forms H- (hydride anions), ... 阅读全帖 |
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R******d
发帖数: 5739 | 13
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i am not a christian and I am neither proud of being one nor proud of not
being one. and I don't think i am arrogant either, merely to point out that
attacking a scientific point without even understanding it is foolish
your
----------------------------
diamond is a metastable state of carbon occuring in nature.
http://en.wikipedia.org/wiki/Metastability
according to this:
http://www.physicsforums.com/showthread.php?t=138720
quote:
----------------------------
For any comp... 阅读全帖 |
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l*****7
发帖数: 8463 | 14 1
http://disinfo.com/2011/05/could-human-photosynthesis-power-the-future/
Could Human Photosynthesis Power The Future?
Posted By: phunkychic666 MAY 4, 2011
Chlorophyll. Photo: Wilfredo R. Rodriguez H. (CC)
Chlorophyll. Photo: Wilfredo R. Rodriguez H. (CC)
By Hank Mills for Pure Energy System News:
Dr. Arturo Solis Herrera has developed a technology that utilizes the
properties of melanin – the animal analogue to chlorophyll. His melanin
based (polihydroxyindol) photo-cell absorbs a broad spectru... 阅读全帖 |
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R*****U
发帖数: 241 | 15 here it is for your reference:
To a three-necked flask equipped with a nitrogen source inlet, an addition
funnel and a cold thermometer, cooled to -5℃ was added a solution of methyl
glycinate hydrochloride 34 (31.7 g, 250 mmol) in water (63 mL) followed by
CH2Cl2 (150 mL). An ice-cold solution of sodium nitrite (20.9 g, 300 mmol)
in water (63 mL) was added and the reaction vessel was cooled to -10℃. An
aqueous solution of H2SO4 (5 wt%, 24 g) was added via the addition funnel
over a 3 min period.... 阅读全帖 |
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p***l
发帖数: 1775 | 16 4-methyl 1-pentyne 跟 EtMgBr 反应
是exothermic还是endothermic?
delta-S 是positive,zero,or negative? |
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