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971.
-(Thiocarbamoylthio)propionic acids derived from alkaloids, morpholine, and piperidine and their esters, amides, and nitriles were prepared by reactions of the corresponding dithiocarbamic acids with acrylic acid and its derivatives. Some of the compounds were tested for insecticidal activity.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 8, 2004, pp. 1336–1339.Original Russian Text Copyright © 2004 by Zhivotova, Gazaliev, Ibraev, Fazylov, Kasenov.  相似文献   
972.
D. VarechJ. Jacques 《Tetrahedron》1972,28(22):5671-5679
A series of bicyclo[2.2.2]octane derivatives whose absolute configurations are known through chemical correlations with confirmed reference products (bicyclo[2.2.2]octanol, bicyclo[2.2.2]octene carboxylic acid) have been prepared.  相似文献   
973.
Intramolecular coordination in dimethylaluminium phenoxides (with an ortho-substituted ring) was investigated. Only strongly donating groups in the phenoxy ring (COOMe) displayed strong intramolecular coordination. All compounds investigated formed donor-acceptor complexes with hexamethylphosphoramide (HMPA). Dimethylaluminium methylsalicilate coordinated HMPA without splitting the intramolecular carbonyl oxygen—aluminium bond, which suggests formation of the pentacoordinated aluminium atom.  相似文献   
974.
We present a new experimental determination of the Compton profiles of CH4 and C2H4 molecules using high energy electron impact. The observable q range has been extended up to 10 au (6 au for C2H4). Good agreement is found with an earlier X-ray scattering experiment and with new theoretical calculations.  相似文献   
975.
The reaction of N-phenylsulfonylbenzoxazolone with amines was investigated in order to study the mechanism of the reaction between aryloxazolones and amines. The sulfonyl group accelerates the reaction considerably. The structure of 2-(phenylsulfamido)phenyl esters of the corresponding N-substituted carbamic acids was assigned to the products on the basis of the IR spectra and alternative synthesis. The reaction with secondary aliphatic amines (dimethyl- and diethylamine)proceeds considerably more slowly and results in the formation of 2-(phenylsulfamido)phenol.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1333–1336, October, 1971.  相似文献   
976.
Rudzinski WE  Yin J  Norman SH  Glaska DA 《The Analyst》1998,123(10):2079-2083
A polyurethane foam (PUF) sponge was mounted in a cassette sampler and evaluated as a sorbent for the collection of hexamethylene diisocyanate (HDI) monomer and HDI-based oligomers. Recovery studies indicated 112 +/- 34% average recovery of HDI monomer and 92 +/- 9% and 97 +/- 25% average recovery of HDI-based oligomers when using impregnated PUF sponges. The PUF sponge was also evaluated during actual spray-painting operations. In a series of side-by-side sampling events, an impinger filled with 1-(2-methoxyphenyl)piperazine (MOP) in toluene was compared directly with a cassette sampler containing a PUF sponge impregnated with MOP or 1-(9-anthracenylmethyl)piperazine (MAP) in dimethyl sulfoxide (DMSO). For the analysis of HDI-based oligomer, there is no significant difference (p < 0.05, n = 7) in the air concentration when sampling with either the PUF sponge cassette or the impinger. The results are significant because they indicate that a PUF sponge, which is more convenient than an impinger, may be used for the collection of HDI-based oligomer generated during spray-painting operations.  相似文献   
977.
Novel approximate methods for calculating the vibrational structure of the electronic spectra of polyatomic molecules—a method for the direct calculation of the overlap integrals of vibrational wave functions for the electronic states involved in a transition and a variational method for the solution of the vibrational problem for the excited states—are discussed. The methods are based on the consideration of the displacement and entanglement of normal coordinates, the quasiorthogonality of the Dushinsky transformation, and the classification of the states by total vibrational quantum numbers. Matrix perturbation theory is employed. It is shown that the accuracy of these methods compares well with the accuracy of the available “exact” techniques (the errors are ∼1 cm−1 for frequency and 10% for relative intensity). At the same time, calculations by the new methods are performed more than two orders of magnitude faster than by the previously known methods. K. A. Timiryazev Agricultural Academy, Moscow. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 2, pp. 217–230, March–April, 1995. Translated by I. Izvekova  相似文献   
978.
Green and red rusts are formed when iron is partially or completely oxidised. Analogues of the rusts may be precipitated from iron(II) and iron (III) salt solutions treated with alkali under reducing or oxidising conditions. Variations in surface area and porosity have been investigated by gravimetric nitrogen gas sorption, using vacuum microbalance techniques.Freshly-precipitated red rusts, hydrous iron (III) oxide, have surface areas of about 200–400 m2g?1. When they are added to iron (II) hydroxide suspensions kept at pH 7, the green Fe (II)-Fe (III) rusts formed have lower surface areas of about 40–100 m2g?1, depending on the initial iron(II) sulphate concentrations.  相似文献   
979.
A simple method of encapsulating water-insoluble pesticides in a starch matrix is described. The method consists of mixing the pesticide with alkali starch followed by precipitation with a calcium chloride solution. A starch–calcium adduct that entraps the pesticide in small cells within granular particles is formed. Liquid and solid pesticides were successfully encapsulated by the new method. By use of the herbicide trifluralin [2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl) benzenamine] as core material more than 90% recovery and encapsulation was achieved. Use of acid-modified starches and flours resulted in a lower percentage of encapsulation. Effective encapsulation was also achieved by replacing calcium chloride with strontium chloride or barium chloride.  相似文献   
980.
L. Pogliani  D. Ziessow 《Tetrahedron》1979,35(24):2867-2873
The 1H and 13C NMR spectra of acetylserine, acetylphosphoserine and acetylphosphothreonine have been measured and completely analysed as a function of pD. For pD> 4 the NMR parameters are only slightly pD dependent. The second titration step of the phosphate group (pK2 = 6.5) is much more difficult to detect in AcPSer (AcPTher) than in PSer (PThr). The ionization of the phosphate is of minor direct influence on the NMR parameters, their comparatively much larger changes in PSer (PThr) are due to conformational changes caused by the electrostatic interaction between the amino and phosphate group. The conformation in which the atoms H-C-Cβ-O-P form a planar W-type arrangement predominates at all pD values in the studied region from 4 to 14 in contrast to the non-cetylated phosphoamino acids in which its percentage passes a minimum at pD 8.  相似文献   
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