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Boron nitrate

Boron nitrate (B + N —> BN) is a white powder used to line high-temperatures furnaces, to make heating crucibles, for electrical and chemical equipment, for heat shields on spacecraft nosecones, and to make high-strength fabrics. [Pg.178]

Datermination of boron, nitrate, perchlorate, rhenium, tungsten, molybdenum. [Pg.1046]

Boron nitrate nanotubes 0.2 PPF Compressive modulus 15% Farshid et al. [Pg.36]

Another aspect of my early research in Budapest was in nitration chemistry, specifically the preparation of nitronium tetrafluoroborate, a stable nitronium salt. 1 was able to prepare the salt in a simple and efficient way from nitric acid, hydrogen fluoride, and boron trifluoride. [Pg.58]

Nitration has also been effected with the complexes from dinitrogen tetroxide and Lewis acidsin the case of boron trifluoride the complex appears to be a mixture of nitronium and nitrosonium tetrafluoroborates. ... [Pg.50]

The cr-complexes (iv) are thus the intermediates corresponding to the substitution process of hydrogen exchange. Those for some other substitutions have also been isolated in particular, benzylidyne trifluoride reacts with nitryl fluoride and boron trifluoride at — ioo°C to give a yellow complex. Above — 50 °C the latter decomposes to hydrogen fluoride, boron trifluoride, and an almost quantitative yield of tn-nitrobenzylidyne trifluoride. The latter is the normal product of nitrating benzylidyne trifluoride, and the complex is formulated as... [Pg.114]

From these results it appears that the 5-position of thiazole is two to three more reactive than the 4-position, that methylation in the 2-position enhances the rate of nitration by a factor of 15 in the 5-position and of 8 in the 4-position, that this last factor is 10 and 14 for 2-Et and 2-t-Bu groups, respectively. Asato (374) and Dou (375) arrived at the same figure for the orientation of the nitration of 2-methyl and 2-propylthiazole Asato used nitronium fluoroborate and the dinitrogen tetroxide-boron trifluoride complex at room temperature, and Dou used sulfonitric acid at 70°C (Table T54). About the same proportion of 4-and 5-isomers was obtained in the nitration of 2-methoxythiazole by Friedmann (376). Recently, Katritzky et al. (377) presented the first kinetic studies of electrophilic substitution in thiazoles the nitration of thiazoles and thiazolones (Table 1-55). The reaction was followed spec-trophotometrically and performed at different acidities by varying the... [Pg.104]

It is also possible to use more powerful reagents to nitrate thiazoles for example, 2-methylthiazole has been nitrated using nitronium tetrafluorobo-rate and the complex nitrogen dioxide-boron tn fluoride (240). The overall yield is about 50 to 60%. [Pg.382]

Phosphine Air, boron trichloride, bromine, chlorine, nitric acid, nitrogen oxides, nitrous acid, oxygen, silver nitrate... [Pg.1211]

Tin(ll) chloride Boron trifluoride, ethylene oxide, hydrazine hydrate, nitrates, Na, K, hydrogen peroxide... [Pg.1212]

Titanium Aluminum, boron trifluoride, carbon dioxide, CuO, halocarbons, halogens, PbO, nitric acid, potassium chlorate, potassium nitrate, potassium permanganate, steam at high temperatures, water... [Pg.1212]

Thousands of compounds of the actinide elements have been prepared, and the properties of some of the important binary compounds are summarized in Table 8 (13,17,18,22). The binary compounds with carbon, boron, nitrogen, siUcon, and sulfur are not included these are of interest, however, because of their stabiUty at high temperatures. A large number of ternary compounds, including numerous oxyhaUdes, and more compHcated compounds have been synthesized and characterized. These include many intermediate (nonstoichiometric) oxides, and besides the nitrates, sulfates, peroxides, and carbonates, compounds such as phosphates, arsenates, cyanides, cyanates, thiocyanates, selenocyanates, sulfites, selenates, selenites, teUurates, tellurites, selenides, and teUurides. [Pg.221]

Lead borate moaohydrate [14720-53-7] (lead metaborate), Pb(B02)2 H20, mol wt 310.82, d = 5.6g/cm (anhydrous) is a white crystalline powder. The metaborate loses water of crystallization at 160°C and melts at 500°C. It is iasoluble ia water and alkaHes, but readily soluble ia nitric and hot acetic acid. Lead metaborate may be produced by a fusion of boric acid with lead carbonate or litharge. It also may be formed as a precipitate when a concentrated solution of lead nitrate is mixed with an excess of borax. The oxides of lead and boron are miscible and form clear lead-borate glasses in the range of 21 to 73 mol % PbO. [Pg.72]

Acid mixtures containing nitric acid and a strong acid, eg, sulfuric acid, perchloric acid, selenic acid, hydrofluoric acid, boron trifluoride, or an ion-exchange resin containing sulfonic acid groups, can be used as the nitrating feedstock for ionic nitrations. These strong acids are catalysts that result in the formation of nitronium ions, NO" 2- Sulfuric acid is almost always used industrially since it is both effective and relatively inexpensive. [Pg.32]

Two colorimetric methods are recommended for boron analysis. One is the curcumin method, where the sample is acidified and evaporated after addition of curcumin reagent. A red product called rosocyanine remains it is dissolved in 95 wt % ethanol and measured photometrically. Nitrate concentrations >20 mg/L interfere with this method. Another colorimetric method is based upon the reaction between boron and carminic acid in concentrated sulfuric acid to form a bluish-red or blue product. Boron concentrations can also be deterrnined by atomic absorption spectroscopy with a nitrous oxide—acetjiene flame or graphite furnace. Atomic emission with an argon plasma source can also be used for boron measurement. [Pg.231]

Great Salt Lake, Utah, is the largest terminal lake in the United States. From its brine, salt, elemental magnesium, magnesium chloride, sodium sulfate, and potassium sulfate ate produced. Other well-known terminal lakes ate Qinghai Lake in China, Tu2 Golu in Turkey, the Caspian Sea and Atal skoje in the states of the former Soviet Union, and Urmia in Iran. There ate thousands of small terminal lakes spread across most countries of the world. Most of these lakes contain sodium chloride, but many contain ions of magnesium, calcium, potassium, boron, lithium, sulfates, carbonates, and nitrates. [Pg.406]

The main metals in brines throughout the world are sodium, magnesium, calcium, and potassium. Other metals, such as lithium and boron, are found in lesser amounts. The main nonmetals ate chloride, sulfate, and carbonate, with nitrate occurring in a few isolated areas. A significant fraction of sodium nitrate and potassium nitrate comes from these isolated deposits. Other nonmetals produced from brine ate bromine and iodine. [Pg.406]

The monothioacetal is also stable to 12 N hydrochloric acid in acetone (used to remove an TV-triphenylmethyl group) and to hydrazine hydrate in refluxing ethanol (used to cleave an A -phthaloyl group). It is cleaved by boron trifluoride etherate in acetic acid, silver nitrate in ethanol, and tiifluoroacetic acid. The monothioacetal is oxidized to a disulfide by thiocyanogen, (SCN)2- ... [Pg.290]

Group 2 Nitrate/metal/sulphur compositions Compositions with >65% chlorate Black powder Nitrate/boron compositions Burn violently Large firework shells Fuse unprotected signal flares Non-pressed report bullets (bird scarers) Report cartridges (unpacked) Black matches (uncovered) Accelerating single-item explosions... [Pg.242]

Electroless nickel-phosphorus should not be used with either fused or hot, strong, aqueous caustic solutions because the coating offers lower resistance to attack than does electrodeposited nickel. As-deposited electroless nickel-boron, however, offers good resistance to hot aqueous caustic solutions It is also resistant to solutions of oxidising salts such as potassium dichromate, permanganate, chlorate and nitrate. [Pg.537]

Nitromum tetrafluoroborate, from nitric acid, boron tnfluonde, and hy drogen fluoride, 47, 56 m nitration of aromatic rings, 47,... [Pg.134]

Notable examples of general synthetic procedures in Volume 47 include the synthesis of aromatic aldehydes (from dichloro-methyl methyl ether), aliphatic aldehydes (from alkyl halides and trimethylamine oxide and by oxidation of alcohols using dimethyl sulfoxide, dicyclohexylcarbodiimide, and pyridinum trifluoro-acetate the latter method is particularly useful since the conditions are so mild), carbethoxycycloalkanones (from sodium hydride, diethyl carbonate, and the cycloalkanone), m-dialkylbenzenes (from the />-isomer by isomerization with hydrogen fluoride and boron trifluoride), and the deamination of amines (by conversion to the nitrosoamide and thermolysis to the ester). Other general methods are represented by the synthesis of 1 J-difluoroolefins (from sodium chlorodifluoroacetate, triphenyl phosphine, and an aldehyde or ketone), the nitration of aromatic rings (with ni-tronium tetrafluoroborate), the reductive methylation of aromatic nitro compounds (with formaldehyde and hydrogen), the synthesis of dialkyl ketones (from carboxylic acids and iron powder), and the preparation of 1-substituted cyclopropanols (from the condensation of a 1,3-dichloro-2-propanol derivative and ethyl-... [Pg.144]

Fluoride ion, and weak acids and bases do not interfere, but nitrate, nitrite, perchlorate, thiocyanate, chromate, chlorate, iodide, and bromide do. Since analysis of almost all boron-containing compounds requires a preliminary treatment which ultimately results in an aqueous boric acid sample, this procedure may be regarded as a gravimetric determination of boron. [Pg.476]

Attempted Nitration of MeNGu Various methods of nitration were attempted including nitric acid alone, or in combination with 100% perchloric acid, zinc chloride, perboric acid, boron trifluoride, etc. All of them gave MeNGu nitrate, described above, but no nitro derivatives (Ref 7, p 3029)... [Pg.130]


See other pages where Boron nitrate is mentioned: [Pg.360]    [Pg.164]    [Pg.208]    [Pg.202]    [Pg.164]    [Pg.6]    [Pg.360]    [Pg.164]    [Pg.208]    [Pg.202]    [Pg.164]    [Pg.6]    [Pg.134]    [Pg.50]    [Pg.205]    [Pg.240]    [Pg.319]    [Pg.327]    [Pg.304]    [Pg.233]    [Pg.233]    [Pg.315]    [Pg.135]    [Pg.351]    [Pg.299]    [Pg.459]    [Pg.163]    [Pg.959]    [Pg.335]    [Pg.444]   
See also in sourсe #XX -- [ Pg.406 ]




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Nitration nitric acid-hydrogen fluoride-boron

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