Gas chromatography – chromatography using a gas as
the mobile phase and a solid/liquid as a stationary phase
– In GC, the analytes migrate in the gas phase, so their
boiling point plays a role
– GC is generally applicable to compounds with masses
up to about 500 Da and with ~60 torr vapor pressure
at room temp (polar functional groups are trouble)
Supercritical fluid chromatography – chromatography
using a supercritical fluid as the mobile phase and a
solid/liquid as a stationary phase
– In SFC, the analytes are solvated in the supercritical
– SFC is applicable to a much ...
Hydrogen cyanide (HCN) is volatile (boiling point: 25.7°C) and weakly acidic (pKa: 9.2). It is bound with cytochrome oxidase to inhibit its activity and induce cellular anoxia; it shows an immediate toxic effects. The fatal dose of HCN is about 100 mg. Cyanide has been being involved in various incidents of suicides, homicides and accidents. It is relatively easy to obtain cyanide, because it is being widely used in metallurgy, metal-plating and other chemical industries. It is a typical poison to be analyzed with high priority.
Alkyl nitrites are highly volatile organic solvents of aliphatic alcohol esters of nitrites . Amyl nitritea, butyl nitrite and isobutyl nitrite are the representative alkyl nitrites; their boiling points are 98, 78 and 67 °C, respectively. Amyl nitrite is being widely used as a detoxicant for cyanide poisoning, because alkyl nitrites oxidize hemoglobin in erythrocytes to yield methemogloblin, which is bound with cyanide to inactivate it .
At one time, computational chemistry techniques were used only by experts
extremely experienced in using tools that were for the most part di½cult to
understand and apply. Today, advances in software have produced programs
that are easily used by any chemist. Along with new software comes new
literature on the subject. There are now books that describe the fundamental
principles of computational chemistry at almost any level of detail.
After attending lectures, reading the text and working assigned problems related to this chapter, students will have acquired the following knowledge and abilities: Given the IUPAC name for a compound containing an amine functional group, be able to draw its structure; know the orbital mechanism for inversion at a pyramidal amine nitrogen; know how the relative electronegativity of N vs. O affects the boiling point, solubility, and basicity of amines vs. alcohols;...
In the distilling plant dirty solvent mixtures are cleaned. The principle is based on the difference of the boiling point between the solvents used as cleaning dilution and the contamination contained in it. The dirty cleaning agent is heated up and easily volatile constituents to evaporate. The boiling point of the assigned solvents amounts to max. 155°C. The materials simmering up to this temperature are led over a cooling column. The condensate consists to a large section of the solvents used as cleaning agents.
Chapter 14 introduce to ethers, epoxides, and sulfides. After completing this chapter, students will be able to: Draw and name ethers and heterocyclic ethers, including epoxides; explain the trends in their boiling points, solubilities, and solvent properties; determine the structures of ethers from their spectra, and explain their characteristic absorptions and fragmentations;...
The idea when we started was to collect the core Emergency Medicine
information and present it in an abbreviated, succinct manner, useful to
housestaff and medical students. As we progressed it became obvious that
the very breadth of the specialty prevented any one person from accomplishing
this task. It also became obvious that our specialty had advanced past the
point where succinctness was possible. We peeled, boiled and pared, and
came up with this. We hope you find it useful.
The arrows that point from the box labeled “Information distilled, interpreted, excerpted” indicate where
this processing occurs. So for instance, scientists and committees process information before handing
it on to policy advisors, and policy advisors do the same before handing information on to policy makers.
And at the end of the chain, complex scientific information often gets boiled down to just a few pages
and messages that reach the desks of the policy makers themselves.
In January 2005 Peg McQueary nicked her ankle while shaving.
It was a tiny cut, but that little opening in her skin provided
a perfect entry point for dangerous bacteria. Two weeks later
McQueary developed a pus-filled boil on her ankle. Shortly
thereafter, her leg swelled to three times its normal size. It was
hot, tender, and painful.
McQueary went to see her doctor. He rushed her to the hospital,
where she was intravenously administered vancomycin,
a powerful antibiotic. It took more than a month for Mc-
Queary’s leg to heal....
Much of the literature on carbon offsets (and nearly all aspiring “standards”) point out
that credible offsets must be “real, surplus, permanent, verifiable, and enforceable” – or
some variation of these terms.
Different sources do not always agree on the definitions
of these criteria, however, and having a “standard” for carbon offsets really depends on
how they are interpreted.
None of the knowledge is mine. What I have learnt is from others. You will find such similar ideas in many books. But I wanted a book that is precise, simple to understand, makes sense and is freely available to anyone. A straight to the point book. This is the effort of many years, boiled, purified and refined to the very basic principles. There are too many people to thank for, far too many to even list them down in this book.