Showing papers on "Halogen published in 1981"

Halogens in the atmosphere

Abstract: Atmospheric halogen measurement data are presented for: (1) inorganic and organic gaseous compounds of chlorine, fluorine, bromine and iodine; and (2) chloride, fluoride, bromide and iodine in particulate form and in precipitation. The roles that these data and other, unavailable data play in the determination of the global cycles of the halogens are discussed. It is found that the speciation of the halogen gases in the troposphere is uncertain, with the only inorganic species detected by species-specific methods being HC1 and SF6. It is shown that heterogeneous reactions, both gas-to-particle and particle-to-gas processes, precipitation removal, and sea-salt aerosol generation and fractionation processes, need quantitative investigation to allow progress in estimating halogen sources and sinks. Where practical, quantitative comparisons are made between measured and predicted concentrations.

Microwave-excited atmospheric pressure helium plasma emission detection characteristics in fused silica capillary gas chromatography

Abstract: Interfacing of fused silica gas chromatographic capillary columns to a microwave-excited atmospheric pressure helium plasma (MED) is investigated. The system for glass and fused silica capillary operation incorporates an interface where excess solvent can be vented by a chemically deactivated fluidic-logic gas switching system. A TM/sub 010/ resonant cavity allows axial viewing of plasma emission. A quartz refractor plate background corrector improves selectivity ratios for elements whose emission occurs in the high-carbon (cyanogen) background region. Background emission characteristics of the helium plasma under various conditions are established from 200 to 500 nm. Calibration curves, selectivity ratios, and detection limits are established for the elements vanadium, niobium, chromium, molybdenum, tungsten, manganese, iron, ruthenium, osmium, cobalt, nickel, mercury, boron, aluminum, carbon, silicon, germanium, tin, lead, phosphorus, arsenic, sulfur, selenium, fluorine, chlorine, bromine, iodine, hydrogen, and deuterium.

A convenient trifluoromethylation of aromatic halides with sodium trifluoroacetate.

Abstract: Regiospecific trifluoromethylation by substitution of the halogen in aromatic halides was achieved by the use of sodium trifluoroacetate and copper(I) iodide. The reaction proceeded smoothly in dipolar aprotic solvents in good to high yields.

Photocatalytic hydrogen production from water by the decomposition of poly-vinylchloride, protein, algae, dead insects, and excrement

Abstract: Xe-lamp irradiation of a platinized TiO2 photocatalyst in the presence of water and chlorine or nitrogen containing organic molecules, synthetic or natural, leads to the production of hydrogen at room temperature without the release of halogen or nitrogen compounds in the gas phase.

Enhanced effect of spray-dried potassium fluoride on fluorination

Abstract: Spray-dried potassium fluoride was found to be much less hygroscopic and much more effective as a fluorinating agent than usual calcine-dried potassium fluoride. Organic compounds containing an activated halogen atom were readily fluorinated in acetonitrile with spray-dried potassium fluoride.

Method of manufacturing hydrogen peroxide

Abstract: A process for producing hydrogen peroxide wherein a gaseous mixture comprising hydrogen and oxygen is contacted with a catalyst in the presence of water and an organic solvent wherein: (i) the organic solvent is immiscible with water and unreactive with hydrogen peroxide under the contacting conditions; (ii) the distribution coefficient for hydrogen peroxide between the water and the organic solvent is greater than 1; (iii) the catalyst is of the formula L 2 MX 2 wherein L is a ligand represented by the formula A R 1 R 2 R 3 wherein R 1 R 2 and R 3 are alkyl, cycloalkyl or aryl groups, hydrogen or halogen, A is a Group 5b element selected from the group consisting of nitrogen, phosphorous and arsenic, M is a Group 8 metal and X is halogen, said catalyst being soluble in said organic solvent and insoluble in water; and (iv) the gaseous mixture is non-ignitable under the process conditions characterized in that the organic solvent is selected from the group consisting of fluorocarbons, halofluorocarbons and mixtures thereof.

Sanitizing complexes of polyoxazolines or polyoxazines and polyhalide anions

Abstract: The title complexes comprise (a) a poly-2-oxazoline or poly-2-oxazine, such as the homopolymers of polymerized 2-ethyl-2-oxazoline or 2-ethyl-2-oxazine, and (b) IBrCl - or polyhalide anion of the formula (XY 2n ) - where X and Y are individually chloride, bromide or iodide, but not both chloride, and n is 1, 2 or 3, and an independently supplied cation selected from the group consisting of alkali metals, alkaline earth metals, hydrogen and mixtures thereof. These complexes are readily prepared in either an aqueous or anhydrous environment at room temperature and are significantly more stable than either complexes of polyoxazolines or polyoxazines and halogen or interhalogen; or complexes of polyvinylpyrrolidone and polyhalide anions.

Composition and method for decomposing hydrogen peroxide

Abstract: A method for decomposing hydrogen peroxide is disclosed. The hydrogen peroxide is reacted with a compound represented by the formula (I) ##STR1## wherein Z represents OH or NR4.R5 wherein R4 and R5 are the same or different and represent hydrogen, alkyl, substituted alkyl or acyl, and R1,R2 and R3 are the same or different and represent hydrogen, halogen, alkyl, alkoxy, amino, nitro, carboxyl or sulphonyl, in the presence of peroxidase.

Method for improving surface properties of shaped articles of synthetic resins

Abstract: The invention provides a novel and efficient method for the improvement of the surface properties of a shaped article of a synthetic resin such as a vinyl chloride-based resin. In particular, the outstanding defective point of the plastic resin articles toward accumulation of static electricity on the surface is greatly reduced by the inventive method, in which the surface of the article is exposed to the low temperature plasma generated in a gaseous atmosphere containing an organic silicon compound followed, preferably, by contacting treatment with a halogen or a halogen compound such as hydrogen halides and halogen-containing organic compounds in a gaseous phase. The organic silicon compound in the gaseous plasma atmosphere is preferably diluted with a diluent gas which may be nitrogen, nitrogen oxides, ammonia or rare gases at a specified partial pressure.

Carbon-13 NMR spectra of polybromoalkanes and polychlorobromoalkanes. Structural increments of halogens in polyhalogenated groups

Abstract: The 13C NMR spectra of 48 polychlorobromoalkanes have been studied. Unlike the 13C signals of chlorine-containing groups (38–105 ppm), those of bromine-containing fragments, with the exception of CBr2 (60–70 ppm), appear in a rather narrow range (25–50 ppm) and are shifted to higher field in relation to similar chlorine-containing groups. The spin–spin coupling constants in similar bromine- and chlorine-containing groups practically coinciEN. Calculation of the chemical shifts for the polyhaloalkanes under study according to the additivity scheme, as previously observed for polychloroalkanes, renders values which are in considerable discord with experimental values (up to –32 ppm for CBr3). These discrepancies may be compensated for by corrections for the binary interaction of halogen atoms by grouping the halogen-containing fragments according to the geminal, vicinal, 1,3-, 1,3,5- and 1,2,3-arrangement of halogen atoms, and by introducing an increment for the position of the halogen at the secondary atom. It is established that as compared to 1-monohaloalkanes: (a) in the case of the geminal arrangement of halogen atoms the α- and γ-effects diminish (Δ α from –3.2 to –8 ppm; Δγ = 2.6 ppm), while the β-effect increases slightly (from 0 to 1.2 ppm); (b) in the case of a vicinal arrangement both the α- and β-effects diminish (by about –3.5 ppm) and the γ-effect remains constant, as if the vicinal system of the halogens was topologically insulated; (c) for the 1,3- and 1,3,5-arrangement of halogens their mutual influence is weak (about –0.5 ppm for each halogen atom in the α- and γ-positions); (d) the 1,2,3 system (serial arrangement of halogen atoms) is the sum of two vicinal fragments and hardly deviates from the additivity scheme; (e) the arrangement of a halogen at the secondary C atom enhances the α-effect (Δα = 2.8 and 1.0 for methyl and methylene, respectively, in the case of Cl, and 3.5 and 3.7 ppm in the case of Br); the variation of the β-effect has a different sign in relation to CH3 and CH2 groups (+1.2 and –1.7 for Cl, and +2.5 and –1.0 for Br). More distant effects of halogens (δ and ϵ) were not considered. The determined increments (Δα, Δβ and Δγ) for the α-, β- and γ-effects of chlorine and bromine atoms allow the prediction of the 13C chemical shifts in polyhaloalkanes with an accuracy up to ±1.5 ppm. Some deviations of up to ±5 ppm may be connected with the influence of a three particle interaction of halogen atoms, which was taken into account only in the case of a geminal arrangement of halogen atoms.

Cyclic Carbene–Palladium(II) Complexes Derived from the Reactions of Isocyanide–Palladium(II) Complexes with Nitrilimines and Nitrilylides

Abstract: cis-[PdCl2(PPh2R1)(CN–C6H4–CH3-p)] (R1=Ph or Et) reacts with nitrilimines or nitrilylides, derived from the reactions of either N-phenylarenecarbohydrazonoyl chlorides or N-(p-nitrobenzyl)arenecarboximidoyl chlorides with triethylamine, to afford novel cyclic carbene–palladium(II) complexes, viz. 1,2,4-triazol-5(4H)-ylideneor 2-imidazolin-5-ylidenepalladium(II) ones, respectively. Halogen exchange reactions of the carbene complexes with lithium bromide or sodium iodide give the corresponding dibromo- or diiodocarbene complexes, respectively. trans-[PdI2(PPh2-C6H4-CH3-p)(CN-C6H4–NO2-p)] also reacts with the nitrilimine or the nitrilylide to produce cyclic carbene–palladium(II) complexes. All the complexes prepared in this study are characterized by elemental analysis, IR and 1H-NMR.

Substituted 1-azolyl-2-ol butanes, their preparation and their application as plant protection agents and as intermediates

Abstract: 1. Substituted 1-azolyl-butan-2-ols of the general formula I see diagramm : EP0055833,P52,F2 in which Az represents 1,2,4-triazol-1-yl or -4-yl or imidazol-1-yl, R**1 represents hydrogen, alkyl with 1 to 12 carbon atoms, alkenyl or alkinyl with in each case 2 to 6 carbon atoms, optionally methyl-substituted cycloalkyl with 3 to 7 carbon atoms or cycloalkylalkyl with 3 to 7 carbon atoms in the cycloalkyl part and 1 to 14 carbon atoms in the alkyl part, or phenylalkyl or phenoxyalkyl with in each case 1 to 2 carbon atoms in the alkyl part, it being possible for the phenylalkyl and phenoxyalkyl groups to be substituted in the phenyl part by halogen, alkyl with 1 to 6 carbon atoms, by methoxy, methylthio, cyclohexyl, dimethylamino, trifluoromethyl, trifluoromethoxy, trifluoromethylthio, by nitro, cyano or alkoxycarbonyl with 1 to 4 carbon atoms in the alkyl part, or by phenyl or phenoxy which are each optionally halogen-substituted, or by the grouping -CO-NR**6 R**7 , n represents 0 or 1, R**2 represents phenyl, which can optionally be substituted by the phenyl substituents mentioned under R**1 , or represents cyano, alkoxycarbonyl with 1 to 4 carbon atoms in the alkyl part or the groupings -X-R**3 or -CO-NR**4 R**5 , wherein X represents oxygen, sulphur or the SO or SO2 group, R**3 represents alkyl with 1 to 4 carbon atoms, phenyl or benzyl, it being possible for the latter two groups to be optionally substituted by the phenyl substituents mentioned under R**1 , R**4 represents hydrogen, alkyl with 1 to 4 carbon atoms or phenyl, it being possible for the latter to be substituted by the phenyl substituents mentioned under R**1 , R**5 represents hydrogen or alkyl with 1 to 4 carbon atoms, and R**6 and R**7 represent hydrogen, alkyl with 1 to 4 carbon atoms or optionally halogen-substituted phenyl, or both, together with the linking nitrogen, represent a morpholine ring, and acid addition salts and metal salt complexes thereof which are tolerated by plants.

Process for the preparation of copolymers of ethylene with at least one other 1-alkene

Abstract: Process for the preparation of copolymers consisting of 25-85% by wt. of ethylene, 15-75% by wt. of at least one other 1-alkene and optionally up to 20% by wt. of a polyunsaturated compound with application of a catalyst system containing a compound of a metal from sub-groups IV-VI of the periodic system and a compound of a metal from groups I-III of the periodic system, in which at least one hydrocarbon group is bound directly to the metal atom via a carbon atom, the polymerization being carried out in the presence of a halogen-containing compound of one of the following groups: a. compounds of the general formula where A is a phenyl or benzoyl group with one or two substituent nitro groups, X is a chlorine or bromine atom, Y is a chlorine, bromine or hydrogen atom or a hydrocarbon group with 1-8 carbon atoms, and Z is a nitrile group, a carboxyl group, an ester group, a hydrocarbyloxyalkylcarboxyl group, a carboxylhalide group, an amide group, a benzoyl group, a carboxyphenyl group, a carboxyhydrocarbylphenyl group, a phenyl group or a phenyldihalogenmethyl group, b. compounds of the general formula where B is a phenyl group which may contain one or two substituent halogen atoms or alkyl groups, or is a thienyl, furyl, pyrrollyl, N alkyl pyrollyl or pyridyl group, which group is bound to the carbon atom directly or via a carbonyl group, X is a chlorine or bromine atom, Y is a chlorine, bromine or hydrogen atom or a hydrocarbon group with 1-8 carbon atoms, and Q is a phenyl group or a phenyldihalogen methyl group. c. oxalyl chloride or oxalylbromide.

Halogen gas leak detector

Abstract: A method and apparatus for measuring the presence of trace amounts of a halogen gas in ambient air by changes in conductivity of a negative corona in an electrical sensing gap due to the presence therein of such electro-negative gas molecules, utilizes a digital feedback loop sensitive to gap corona current to adjust the high voltage producing the corona discharge to obtain the optimum corona current for best sensitivity irrespective of the concentration of the halogen contaminant present. The presence of the halogen gas contaminant in the air is indicated by a bi-level audible alarm consisting of a periodically interrupted tone the frequency of which goes above or below a base line value to indicate small variations in impurity concentration above or below the base line concentration, and the tone interruption rate of which, at the same time, increases for large impurity concentrations.

Complex compounds, process for their preparation, and their use

Abstract: A complex compound of a metal salt or metalloid salt and an ansolvo-acid or proton-acid, of the general formula I M.sub.n.sup.m.X.sub.m.sup.n.pY.qZ (I) in which M is a m-valent cation of a metal or metalloid, a metal-oxy or metal-dioxy cation or a hydrogen atom, X is a n-valent anion of a n-basic inorganic proton-acid or of a n-basic organic acid selected from the group of the aliphatic and cycloaliphatic carboxylic acids with up to 8 C atoms, which can be substituted by halogen and/or hydroxyl groups, the aromatic monocarboxylic, dicarboxylic and tricarboxylic acids, which may be substituted by hydroxyl, halogen and/or nitro groups, the organic oxyacids of phosphorus and sulphur, the organic thioacids of phosphorus, and the mercaptans, the inorganic or organic acid having a pKa value of at most 15.8 or, if M is a proton, of at most 11, Y is water or a neutral organic molecule which can be bound coodinatively by the cation or the anion, Z is a complex-forming vicinal diol with at least 6 C atoms, p is 0 or a value between 0 and 2, q is a value from 1 to 32, m is an integer from 1 to 6 and, if M is a hydrogen atom, is 1 and n is an integer from 1 to 4, and mixtures of such compounds.

Detection of impurities in a fluid containing free gas using nuclear techniques

Abstract: Fluid containing free gas and in a pipeline or container at a refinery or at any of various petroleum producing operations is bombarded with neutrons and high energy gamma rays resulting from capture of thermal neutrons are detected The spectra of the detected gamma rays are then analyzed to determine the concentration of the elements chlorine and hydrogen The counting rate for thermal neutron gamma rays for hydrogen permits a measure of the hydrogen index (HI) of the fluid to be obtained The hydrogen index and the relative concentrations of chlorine and hydrogen are used to obtain an indication of the presence and concentration of chlorine or salt water in the fluid

Pyrimidine-2-sulphides and their S-oxides for use in medicine, pharmaceutical compositions containing them, processes for their preparation and such compounds when novel per se

Abstract: Compounds of the formula (wherein X represents a halogen atom; nis 0,1 or 2; R 1 and R 2 , which may be the same or different, each represents a hydrogen atom or a carboxyl, esterified carboxyl, amido or mono-or di-C1-4 alkylamido group or a C1-4 alkyl group which may if desired carry a carboxyl or esterified carboxyl group; and R 3 represents a Ci-32 saturated or unsaturated, straight or branched, cyclic or acyclic aliphatic group or an araliphatic or heterocyclic substituted aliphatic group, a heterocyclic group or an aryl group which groups may if desired carry one or more substituents selected from halogen atoms and oxo, nitro, hydroxy, etherified hydroxy, esterified hydroxy, primary, secondary or tertiary amino, acylamino etherified mercapto or S = 0 or -SO 2 derivatives thereof and esterified phosphoric acid groups) and, where an acidic or basic group is present, physiologically compatible salts thereof have been found to be of use in combating abnormal cell proliferation. The compounds are prepared inter alia by oxidation of the corresponding sulfide, displacement of a leaving atom or group from the 2-position of the pyrimidine by reaction with a sulfinic acid or by ring closure of the pyrimidine ring.

Electro-chemical cells

Abstract: OF THE INVENTION The invention relates to an electro-chemical cell having an electrolyte comprising water, a halogen other than fluorine, a halide other than fluoride, which is not oxidised by the halogen as a soluble salt, and a stable, saturated, organic nitrile or dinitrile containing from 2 to 5 carbon atoms or a mixture thereof, said electrolyte being composed such as to exist in two phases, a first phase being halogen and nitrile-rich and a second phase being water-rich and con-taining halide salt, the cell having an inert electrode in the halogen and nitrile-rich phase and an electrode, con-taining or contacting halogen oxidisable material, in the water-rich phase. The electro-chemical cell of the invention is particularly applicable to systems containing zinc as the halogen oxidisable material. The use of the nitrile-rich phase reduces the degree of reaction between the halogen and the halogen oxidisable material.

Metal derivatives of azoles, part VII. Pyrazolato-bridged dinuclear complexes containing either cyclopalladated or -platinated trimesitylphosphine or -arsine

Abstract: The halogen bridges of the dimeric, cyclometallated trimesityl-arsine and -phosphine complexes of palladium(II) and platinum(II), where M=Pd or Pt and E=P or As have been replaced with pyrazolate groups to give the corresponding and less symmetric pyrazolato-bridged complexes, where M=Pd or Pt, E=P or As, Pz=pyrazolato anion, and M=Pd, E=As, Pz=3,5-dimethylpyrazolato anion. In the case of the palladium complexes,1H. n.m.r. clearly indicates the presence of only one isomer which is most likely to have thetrans configuration while the platinum complexes are mixtures of bothcis andtrans forms.