allied chemical says we did it first in nj

while growing crystals in an environment of hydrogen sulfide we vented the gas to the atmodphere only to didcover the lsb's rooftop exhaust vent was adjacent to the intake vent.  thar she blows

what can you expect from a company thst fured the akexandrite crystal groeing department only to recall them weeks later and tell them that they were weeks behind schrduke.alexandrite makes for tunable lasers

the australians fidcovered tbat people study chemistry while american eecute themselves safeky and effectively with feantanyl while states use combinstions of substances that are vastly inferior


make america great again fentsnyl, heroin, and morphine for all and morphine otofucing yeast in every microbrewery

Characteristics of Alexandrite Lasers In Q-Switched And Tuned Operations

C. L. Sam ; J. C. Walling ; H. P. Jenssen ; R. C. Morris ; E. W. O'Dell

[-] Author Affiliations

C. L. Sam, J. C. Walling, H. P. Jenssen, R. C. Morris, E. W. O'Dell

Allied Chemical Corporation (United States)

Proc. SPIE 0247, Advances in Laser Engineering and Applications, 130 (October 31, 1980); doi:10.1117/12.959391

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From Conference Volume 0247

• Advances in Laser Engineering and Applications
• Malcolm L. Stitch
• San Diego | July 29, 1980

Abstract

abstract

Alexandrite is a laser crystal which is unique in that it is broadly tunable, is four-level, and has a long storage time making Q-switched operation possible. In addition the crystal is surpassed only by ruby in desirable strength and thermal properties of all practical laser crystals. A simple four-level model that describes the laser operation in alexandrite is presented. The terminal laser level in this model is a set of vibrational states well above the ground state. The initial laser level is a level 800 cm-1 above a long-lived storage level and in thermal equilibrium with it. Experimental results of Q-switched operation and tuned long pulse operation are presented, both as a function of temperature. In Q-switched operation, pulsewidths from 70 ns to 300 ns have been measured and laser efficiency increases with temperature. In tuned operation, the increase in gain with temperature is accompanied by a shift of the tuning curve to the red. Both observations are consistent with the simple model. Some laser design parameters are discussed.

© (1980) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Topics

Alexandrite lasers ; Q switching ; Lasers ; Alexandrite ; Data storage ; Laser crystals ; Laser development ;Crystals ; Ruby

Citation

C. L. Sam ; J. C. Walling ; H. P. Jenssen ; R. C. Morris and E. W. O'Dell
"Characteristics of Alexandrite Lasers In Q-Switched And Tuned Operations", Proc. SPIE 0247, Advances in Laser Engineering and Applications, 130 (October 31, 1980); doi:10.1117/12.959391; http://dx.doi.org/10.1117/12.959391

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Hydrogen sulfide

Chemical compound

Hydrogen sulfide (British English: hydrogen sulphide) is the chemical compound with the formula H₂S, is a colorless, toxic, flammable gas that is responsible for the foul smell of rotten eggs and flatulence. It often results when bacteria break down organic matter in the absence of oxygen. This happens in swamps, and sewers (alongside the process of anaerobic digestion). It also occurs in volcanic gases, natural gas and some well waters. This is the smell that people often think to be that of sulfur. But sulfur itself does not smell.

Hydrogen sulfide
Systematic name Hydrogen sulfide[1]
Other names	Dihydrogen monosulfide Dihydrogen sulfide Sewer gas Stink damp Sulfane Sulfurated hydrogen Sulfureted hydrogen Sulfuretted hydrogen Sulfur hydride
Identifiers
CAS number	7783-06-4
PubChem	402
EC number	231-977-3
KEGG	C00283
MeSH	Hydrogen+sulfide
ChEBI	CHEBI:16136
RTECS number	MX1225000
SMILES	S
InChI
Beilstein Reference	3535004
Gmelin Reference	303
3DMet	B01206
Properties
Molecular formula	H2S
Molar mass	34.08 g mol-1
Appearance	Colorless gas
Odor	faint rotten egg
Density	1.363 g dm-3
Melting point	-82 °C, 191 K, -116 °F
Boiling point	-60 °C, 213 K, -76 °F
Solubility in water	4 g dm-3 (at 20 °C)
Vapor pressure	1740 kPa (at 21 °C)
Acidity (pKa)	7.0[2]
Basicity (pKb)	6.95
Refractive index (nD)	1.000644 (0 °C)[3]
Structure
Molecular shape	Bent
Dipole moment	0.97 D
Thermochemistry
Std enthalpy of formation ΔfHo298	−21 kJ·mol−1[4]
Standard molar entropy So298	206 J·mol−1·K−1[4]
Specific heat capacity, C	1.003 J K-1 g-1
Hazards
EU classification	F+ T+  N
EU Index	016-001-00-4
NFPA 704	4 4 0
R-phrases	R12, R26, R50
S-phrases	(S1/2), S9, Template:S16, S36, Template:S38, S45, S61
Flash point	-82.4 °C.[5]
Autoignition temperature	232 °C
Explosive limits	4.3–46%
Related compounds
Related hydrogen chalcogenides	Water Hydrogen selenide Hydrogen telluride Hydrogen polonide Hydrogen disulfide Sulfanyl
Related compounds	Phosphine
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)

Hydrogen sulfide is also known as sulfane, sulfur hydride, sour gas, sulfurated hydrogen, hydrosulfuric acid, sewer gas and stink damp. IUPACaccepts the names "hydrogen sulfide" and "sulfane". When people speak of more complicated compounds they always use the term "sulfane".

Contents

Occurrence

SafetyEdit

Hydrogen sulfide is a highly toxic and flammable gas. Because it is heavier than air it tends to accumulate at the bottom of poorly ventilated spaces.

ToxicityEdit

Hydrogen sulfide is considered a broad-spectrum poison, meaning that it can poison several different systems in the body, although the nervous system is most affected. The toxicity of H₂S is comparable with that of hydrogen cyanide.

ReferenceEdit

1. ↑ "Hydrogen Sulfide - PubChem Public Chemical Database". The PubChem Project. USA: National Center for Biotechnology Information. http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=402&loc=ec_rcs.
2. ↑ Perrin, D.D., Ionisation Constants of Inorganic Acids and Bases in Aqueous Solution, 2nd Ed., Pergamon Press: Oxford, 1982.
3. ↑ Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw-Hill, 2002, ISBN 0-07-049439-8
4. ↑ ^4.0 4.1 Zumdahl, Steven S. (2009). Chemical Principles 6th Ed.. Houghton Mifflin Company. p. A23. ISBN 0-618-94690-X.
5. ↑ Hydrogen sulfide: Overview, National Pollutant Inventory, Australia
6. ↑ "Southern Natural Gas Company Tariff, General Terms and Conditions Section 3.1(b)". http://ixsnp.sonetpremier.com/ebbmasterpage/Tariff/OrgChart.aspx?code=SNG&pdftag=gtcq. Retrieved October 18, 2011.

• "Hydrogen Sulfide", Committee on Medical and Biological Effects of Environmental Pollutants, University Park Press, 1979, Baltimore. ISBN 0-8391-0127-9

Other websitesEdit

• International Chemical Safety Card 0165
• Concise International Chemical Assessment Document 53
• National Pollutant Inventory - Hydrogen sulfide fact sheet
• NIOSH Pocket Guide to Chemical Hazards
• MSDS safety data sheet
• Abstract of survey article on H₂S as used by the body, by P. Kamoun
• Computational Chemistry Wiki