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Topic: Monomethylhydrazine

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	Gemini Press Reference Book
		The combustion chamber and the expansion nozzle are lined with an ablative material which maintains internal geometry and protects the external wall from temperature damage.
		The oxidizer is nitrogen tetroxide; the fuel is monomethylhydrazine.
		The oxidizer and fuel propellant tanks are all-welded titanium spherical structures.
	www.apollosaturn.com /geminiNR/sec8.htm (1254 words)

	Nat' Academies Press, Acute Exposure Guideline Levels for Selected Airborne Chemicals: Volume 1 (2000)
		Earlier data were summarized regarding the pharmacologic and toxicologic effects of monomethylhydrazine in laboratory animals by various routes of administration, noting involvement of the central nervous system, lungs, liver, and kidneys.
		(1955) assessed the lethality of monomethylhydrazine in hamsters exposed for 4 h.
		Syrian golden hamsters were exposed to monomethylhydrazine at concentrations of 460, 620, 810, 910, 1,110, or 1,380 ppm for 1 h followed by a 14-d observation period.
	www.nap.edu /books/0309072948/html/113.html (5195 words)

	Further studies on the ex-vivo effects of procarbazine and monomethylhydrazine on rat semicarbazide-sensitive amine ...
		Further studies on the ex-vivo effects of procarbazine and monomethylhydrazine on rat semicarbazide-sensitive amine oxidase and monoamine oxidase activities.
		In a parallel in-vitro study, monomethylhydrazine was without effect on MAO A in brown adipose tissue homogenates.
		Following administration of the anticancer agent, procarbazine, or one of its metabolites, monomethylhydrazine, to rats, activities of monoamine oxidases A and B (MAO A and MAO B) and of semicarbazide-sensitive amine oxidase (SSAO) were measured ex-vivo.
	www.ihop-net.org /UniPub/iHOP/gp/495443.html (256 words)

	MSN Encarta - Print Preview - Mushroom
		Medically, the most important toxins formed by fungi are ibotenic acid, muscarine, monomethylhydrazine, and the amatoxins.
		Ibotenic acid is the principal toxin in the fly amanita, even though muscarine is so named because it is found in that mushroom; muscarine is also synthesized by other poisonous mushrooms.
		Monomethylhydrazine occurs in the poisonous false morels, which may be mistaken for true morels.
	encarta.msn.com /text_761561803___3/Mushroom.html (659 words)

	Gelled monomethylhydrazine thixotropic fuel - Patent 4039360
		The particular thixotropic fuel is particularly characterized by the fact that a low gellant concentration can be used and by the fact that the metallic fuel particles can be suspended with no separation or settling out of the metallic fuel particles in the fuel even when subjected to 500 g's.
		A composition consisting of monomethylhydrazine present in an amount of about 36 to about 40 weight percent, hydroxyalkyl cellulose present in an amount of about 1 to about 3 weight percent, metallic fuel particles, and dimethylurea present in an amount of about 0.05 to about 0.3 weight percent to form a gelled fuel.
		The composition of claim 1, wherein said hydroxyalkyl cellulose is hydroxypropyl cellulose, and wherein the remainder is composed of said metallic fuel particles, said metallic fuel particles being selected from the group consisting of aluminum, magnesium, boron, beryllium, lead, zirconium, aluminum hydride, magnesium hydride, boron hydride, beryllium hydride, lead hydride and zirconium hydride.
	www.freepatentsonline.com /4039360.html (975 words)

	N2O4/MMH
		Monomethylhydrazine (MMH) is 95+ per cent pure, while the normally expected impurities are methylamine and water.
		MMH is not sensitive to impact or friction; it is more stable than hydrazine on mild heating and similar to hydrazine in sensitivity to catalytic oxidation.
		Monomethylhydrazine may be produced by a modified Raschig process; methylamine is substituted for ammonia in the reaction with chloramine.
	www.friends-partners.org /partners/mwade/props/n2o4mmh.htm (446 words)

	SFS (Site not responding. Last check: 2007-11-05)
		ISO 15859-6:2004 specifies limits for the composition of monomethylhydrazine and establishes the sampling and test requirements applicable for the verification of the monomethylhydrazine (MMH) composition.
		ISO 15859-6:2004 is applicable to monomethylhydrazine propellant, used as a fuel in propellant systems of space systems as well as in both flight hardware and ground facilities, systems, and equipment, of Grade A (98,0 % pure) and Grade F (98,5 % pure).
		ISO 15859-6:2004 is applicable to any sampling operation required to ensure that, when the fluid enters the launch vehicle or spacecraft, the fluid composition complies with the limits provided hereafter or with any technical specification agreed to for a particular use.
	www.sfs.fi /luettelo/iso.php?standard=037281 (134 words)

	Active Skim View of: Monomethylhydrazine: Acute Exposure Guideline Levels
		Inhalation ' + 'of monomethylhydrazine was not carcinogenic in rats or dogs, but mice exposed at 2 ppm for 1 y exhibited an increased incidence of lung tumors, nasal adenomas, ' + 'nasal polyps, nasal osteomas, hemangioma, and liver adenomas and carcinomas.
		That is a reasonable estimate of the lethality threshold, because monomethylhydrazine has a steep exposure-response curve, ' + 'and data on other chemicals with similar dose response curves indicate that this approach represents a likely estimate of the threshold for lethality.
		monomethylhydrazine toxicity, and the most ' + 'closely related to humans, an uncertainty factor of 3 is justified.
	www.nap.edu /nap-cgi/skimit.cgi?isbn=0309072948&chap=113-154 (10177 words)

	Devices and methods for the detection of basic gases - Patent 6328932
		The intensity of the sensor response to either ammonia 72 (10 ppm), hydrazine 73 (500 ppb), monomethylhydrazine 74 (84 ppb) or 1,1'-dimethylhydrazine 75 (30 ppb) in air relative to the sensor response in air alone is plotted vs. wavelength in FIG.
		A polymer/dye film coated sensor prepared as above was exposed to monomethylhydrazine vapor and the sensor was shown to be useful for detection (and quantitation) of monomethylhydrazine.
		The relative sensitivities of this sensor to hydrazine, monomethylhydrazine and ammonia at.lambda.=635 nm are 20:1:0.06, respectively.
	www.freepatentsonline.com /6328932.html (11393 words)

	Ion-Mobility Spectrometric Determination of Hydrazines (Site not responding. Last check: 2007-11-05)
		Hydrazine, monomethylhydrazine, and unsymmetrical dimethylhydrazine can be detected and measured at concentrations as low as 10 parts per billion in the presence of ammonia at concentrations as high as 10 parts per million (greater than the odor threshold concentration of ammonia, approximately 5 ppm) by modified use of a portable, commercially available ion-mobility spectrometer.
		The modification consists in the substitution of 5-nonanone for acetone as the ion-forming compound in the drift or source region of the ion-mobility spectrometer.
		Previously, when acetone was used and ammonia was present in the sampled atmosphere even at ppm levels, chemical reactions between the ammonia and the acetone formed ion adducts that had mobilities comparable to those of monomethylhydrazine and that, consequently, interfered with the detection of hydrazines.
	www.nasatech.com /Briefs/Nov99/MSC21966.html (352 words)

	Active Skim View of: Monomethylhydrazine: Acute Exposure Guideline Levels
		Hamsters exposed at 2 or 5 ppm exhibited an increased incidence in nasal polyps, ' + 'interstitial fibrosis of the kidney, and benign adrenal adenomas.
		Mechanism of Toxicity The precise mechanism of monomethylhydrazine toxicity ' + 'is uncertain.
		(1955) assessed the lethality of monomethylhydrazine in hamsters exposed ' + 'for 4 h.
	www.nap.edu /nap-cgi/skimit.cgi?isbn=0309072948&chap=113-154 (10177 words)

	NASA WSTF HEBF Propellant Reaction Characterization Studies
		The objective of these tests is to determine the overpressure environments (near- and far-field) that are produced by monomethylhydrazine and nitrogen tetroxide mixtures under specific distributed mixing conditions.
		Tests performed with stoichiometric mixtures of propellants at approximately 68 kg (150 lb) were designed to establish the upper side-on pressure limit that could be generated during an intact impact scenario using selected propellant combinations.
		It was determined that monomethylhydrazine would be placed into glass ampules (approximately 1 liter), sealed, and secured in a sealed test pan for the monomethylhydrazine and nitrogen tetroxide tests.
	www.wstf.nasa.gov /Hazard/Explosion/HEBFReaction.htm (206 words)

	Recovery of Monomethylhydrazine Liquid Propellant by Pervaporation Technique (Site not responding. Last check: 2007-11-05)
		Monomethylhydrazine (MMH) is a well-known liquid propellant used as fuel for launching of rockets and satellites.
		The desalted reaction liquor of MMH contains about 2 wt % of the propellant (balance water), which also forms an azeotrope with water at 35% MMH concentration.
		Finally aging studies have been carried out to determine the life of the membrane in the propellant medium.
	pubs.acs.org /cgi-bin/abstract.cgi/iecred/2000/39/i07/abs/ie990776c.html (196 words)

	[No title] (Site not responding. Last check: 2007-11-05)
		Galileo uses monomethylhydrazine for its fuel, the same fuel used to launch Titan missiles, and also to control the position of the space shuttle once in orbit.
		There are many reasons nitrogen tetroxide and monomethylhydrazine were chosen to propel Galileo--long history, low freezing point, good performance, space storability, etc. However, one of the main reasons this combination was used was because these two propellants are hypergolic.
		I invite the reader to research the meaning of the word "hypergolic" and try to understand why this is important for the Galileo mission, with many tens-of-thousands of thruster firings.
	quest.arc.nasa.gov /galileo/Galileo-QA/Fuel/Fuel__propellant.1 (272 words)

	:: NASA Quest > Archives :: (Site not responding. Last check: 2007-11-05)
		To understand why it's so important to keep the fuel and oxidizer separate, I should mention here that the RPM is what is known as a "bipropellant" system, utilizing nitrogen tetroxide as the oxidizer and monomethylhydrazine (mono methel hi dra zeen) as the fuel.
		Nitrogen tetroxide and monomethylhydrazine are hypergolic--meaning, they ignite on upon contact--so keeping them from mixing, except in the rocket engines (for which they were designed to mix in a controlled manner), is an important safety consideration for the whole spacecraft!
		In the last two months or so, I have been mainly concerned with keeping the spacecraft safe by minimizing propellant tank temperature excursions, or changes in the tank temeperature, in case this oxidizer check valve really is stuck open.
	quest.arc.nasa.gov /galileo/journals/junior/jrjournal5.html (1041 words)

	:: NASA Quest > Archives :: (Site not responding. Last check: 2007-11-05)
		To understand why it's so important to keep the fuel and oxidizer separate, I should mention here that the RPM is what is known as a "bipropellant" system, utilizing nitrogen tetroxide as the oxidizer and monomethylhydrazine as the fuel.
		Nitrogen tetroxide and monomethylhydrazine are hypergolic--meaning, they ignite on upon physical contact--so keeping them from mixing except in the rocket engines (for which they were designed to mix in a controlled manner) is an important safety consideration for the whole spacecraft!
		In the last two months or so, I have been primarily concerned with keeping the spacecraft safe by minimizing propellant tank temperature excursions in case this oxidizer check valve really is stuck open.
	quest.arc.nasa.gov /galileo/bios/fjournals/barber-ofj1.html (865 words)

	[No title] (Site not responding. Last check: 2007-11-05)
		Two monohydrates of monomethylhydrazine are formed by annealing at low temperature (T < 218.9 K) of supercooled stoichiometric mixtures of monomethylhydrazine and water.
		A non-isothermal method based on the Johnson-Melh-Avrami formalism was developed to measure Avrami's exponent and the crystal growth kinetic constant of the two monomethylhydrazine monohydrates.
		It was also shown that the formation of each solid phase is controlled by two kinds of nuclei.
	www.elsevier.com /cdweb/journals/00220248/articles/180/2/S002202489700211.abstract.en (116 words)

	SBIR/STTR Interactive Topic Information System (SITIS)
		This effort would develop an automated, continuous hypergolic leak detection network that does not require calibration or routine maintenance for at least four years.
		The system must be able to detect to a few parts-per-billion (ppb) any of the common types of hypergolic fuels and oxidizers including monomethylhydrazine (MMH), unsymmetric dimethylhydrazine (UDMH), and nitrogen tetroxide (NTO).
		It should be readily integrateable with existing components such as missiles, missile canisters, shipboard electronics, passageways, and alarm systems.
	www.dodsbir.net /Sitis/archives_display_topic.asp?Bookmark=19473 (570 words)

	HELVELLACEAE in the Pacific Northwest
		Some specimens, particularly in other parts of the country, contain monomethylhydrazine or other compounds that liberate monomethylhydrazine upon ingestion.
		Furthermore, there are indications that monomethylhydrazine is carcinogenic, even when ingested in amounts that do not produce immediate symptoms of poisoning.
		Parboiling in an open vessel and discarding the water reduces the risk somewhat, as the poison is volatile and water soluble.
	www.svims.ca /council/Helvel.htm (3656 words)

	Re: [amsat-bb] Rocket Science (Site not responding. Last check: 2007-11-05)
		The shuttle OMS and RCS utilize > > monomethylhydrazine (MMH) and nitrogen tetroxide (n2o4), which, when mixed, > > ignite producing thrust.
		> > The nitrogen tetroxide is the oxidizer, so that the monomethylhydrazine > can burn in the vacuum of space.
		N2 is such a stable molecule, it might be a driving force for the release of oxygen.
	www.uk.amsat.org /ListArchives/amsat-bb/1999/msg04802.html (393 words)

	Conductive Polymer Films as Ultrasensitive Chemical Sensors for Hydrazine and Monomethylhydrazine Vapor (Site not responding. Last check: 2007-11-05)
		Thin films of the electrically conductive polymer poly(3-hexylthiophene) were investigated as ultrasensitive chemical sensors for hydrazine and monomethylhydrazine vapor.
		The threshold limit value for these highly toxic species, which are used extensively as rocket fuels, has recently been lowered to 10 ppb for 8-h exposure, necessitating the development of instrumentation with improved sensitivity.
		O and have a shelf-life of several years when stored in cold, dry conditions.
	pubs.acs.org /cgi-bin/jtext?ancham/68/i05/abs/ac950662k (232 words)

	California Fungi: Gyromitra esculenta
		Anecdotal evidence and preliminary tests by Duffy and Vergeer suggest that California material may not contain high levels of MMH, but caution is still advised.
		Although we cannot recommend eating this mushroom, it is commonly consumned in the Western United states.
		If you do try Gyromitra esculenta, it should always be cooked in a well ventilated area to avoid breathing any monomethylhydrazine that might be present and the cooking liquid should be discarded.
	www.mykoweb.com /CAF/species/Gyromitra_esculenta.html (407 words)

	Boeing: Rocketdyne: Peacekeeper Post Boost Propulsion System (Site not responding. Last check: 2007-11-05)
		The structure is fabricated from aluminum and includes external protection material, a Stage III/PBPS separation joint and access panels.
		The liquid bipropellant propulsion system utilizes hypergolic propellants, Monomethylhydrazine (MMH) and Nitrogen Tetroxide (NTO).
		Eight 70 lbs-thrust engines are used for attitude control and one 2563 lbs-thrust engine is used for vectored axial thrust.
	www.boeing.com /defense-space/space/propul/peacekpr.html (180 words)

	Morels! - How to find, identify and prepare them
		Related species including G. gigas, G. korfii and the genera Verpa and Helvella may also contain traces of hydrazines.
		Believe it or not, monomethylhydrazine is a key component of rocket fuel.
		Eating mushrooms containing hydrazines raw has caused many documented fatalities (mostly in Europe.) Cooking and/or drying can remove the volatile Gyromitrin poison, hence people have eaten these mushrooms for years with no ill effects.
	theforagerpress.com /fieldguide/morels (756 words)

	VC2: Ask-A-Chemist: What Makes Some Mushrooms Poisonous (Site not responding. Last check: 2007-11-05)
		False morel mushrooms (Gyromitra esculenta) are poisonous because they contain gyromitrin, which breaks down into the toxic and carcinogenic substance monomethylhydrazine.
		Monomethylhydrazine can be avoided by cooking the mushrooms in an uncovered pan.
		Common inky cap mushrooms (Coprinus atramentarius) contain coprine, a compound that inhibits the digestion of alcohol, thereby producing poisonous acetaldehyde�the normal product initially formed from ethanol by the liver enzyme alcohol dehydrogenase.
	acs.org /portal/a/c/s/1/acsdisplay.html?DOC=vc2\5qx\qx5_mushrooms.html (397 words)

	Environmental Fate of Hydrazine Fuels in Aqueous and Soil Environments - Storming Media
		Despite their hypergolic nature, these fuels are remarkably stable in uncatalyzed aqueous solutions.
		Monomethylhydrazine (MMH) and unsymmetrical dimethylhydrazine (UDMH) were found to be extremely stable in distilled water, and had slow half-lives (10-14 days) in ponds and seawaters.
		As this study minimized biological decomposition and phase transfer losses, the aqueous half-lives of 10-14 days are very conservative figures and represent worst case situations.
	www.stormingmedia.us /31/3185/A318521.html (155 words)

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