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981.
The polymerization of methyl 2-cyanoacrylate and heptyl 2-cyanoacrylate was carried out with the use of aqueous solutions of 14C-tagged glycine, methyl glycine, and acetyl glycine as initiators. When glycine and methyl glycine were used, radioactive polymers were formed. When acetyl glycine was used, the polymer formed was not radioactive. The data seem to indicate that free NH2 groups appear to be necessary for the incorporation of the glycine initiator in the polymer. A possible mechanism for the polymerization is presented.  相似文献   
982.
The infrared and ultraviolet spectra of many pyridine N-oxide derivatives have been studied. Ultraviolet spectra show a strong solvent effect in going from aprotic to hydroxylic solvents due to strong hydrogen bonding. Values of δ H° for several systems CH3OH/XPyNO in tetra-chloroethylene solution were evaluated by infrared techniques and a linear correlation δ H° vs. δ v OH has been found. Features of the infrared and ultraviolet characteristic absorption bands were also investigated.  相似文献   
983.
Summary Spot tests have been described for calcium sulphate, lead sulphate, silver, thallium and formaldehyde based on the reaction with selenosulphate. In these reactions either red elemental selenium (CaSO4, CH2O) or black metal selenide (PbSO4 Tl, Ag) is formed. The limits of identification are: 0.2 mg of PbS04 or CaSO4, 2 g of Ag, 10 g of Tl, 0.2 g of CH2O.
Zusammenfassung Für Calciumsulfat, Bleisulfat, Silber, Thallium und Formaldehyd werden Tüpfelproben beschrieben, die auf Umsetzungen mit Selenosulfat beruhen. Hierbei -wird entweder rotes elementares Selen abgeschieden (CaSO4 CH2O) oder schwarze Selenide werden gebildet (PbSO4, Tl, Ag). Die Nachweisgrenzen betragen: 0,2 mg PbSO4 oder CaSO4, 2 g Ag, 10 g Tl, 0,2 g CH2O.


This paper has been dedicated to Prof. Dr.Fritz Wessely, Vienna, on the occasion of his 70th birthday.  相似文献   
984.
    
Zusammenfassung Wird die Kondensation von o-Aminophenol und Glyoxal zur Schiffschen Base Glyoxal- bis [2-hydroxyanil] in Gegenwart von Calciumoxyd vorgenommen, so entsteht bei Zimmertemperatur unmittelbar das rote innerkomplexe Calciumsalz der Schiffschen Base. Dies ermöglicht den Nachweis von Glyoxal und von o-Aminophenol in der Arbeitsweise der Tüpfelanalyse. Es werden Erfassungsgrenzen von 1 g Glyoxal und 25 g o-Aminophenol erreicht.  相似文献   
985.
Zusammenfassung Aus 1,3,5-Triphenyl-verdazyl (1) entsteht mit Azo-isobuttersäurenitril das farblose Tetrazinderivat3, das beim Erhitzen unter Zerfall der gebildeten C-N-Bindung das grüne Radikal1 zurückliefert.
1.3.5-Triphenylverdazyl yields with 2.2-azobis[2-methylpropionitril] the colourless tetrazine-derivative3, which upon heating reverts to the green radical1 via dissociation of the C-N bond.


9. Mitt.:R. Kuhn, F. A. Neugebauer undH. Trischmann, Mh. Chem.97, 846 (1966).  相似文献   
986.
The equilibrium and kinetic characteristics of uranium sorption from simulated sulfuric acid leaching solutions by AMP, Lewatit K 6367, Purolite A 500, Purolite A 600, and AM-p gel-like and porous strongly basic anion exchangers were studied.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 5, 2005, pp. 736–740.Original Russian Text Copyright © 2005 by Kolomiets, Troshkina, Sheremet’ev, Konopleva.  相似文献   
987.
In this work Strontium was separated selectively form, Pd2+, Ni2+ and Ca3+ using anionic resins of Amberlite type IRA-900 and IRA-410 from nitrate medium. The Separation of strontium by strongly basic anion exchangers IRA-410 and IRA-900 from simulated waste containing, Sr2+, Eu3+, Ce3+, Pd2+, Rh3+, Ru3+, VO2 2+, Fe3+, Cr3+, Ni2+, Al3+, Ca2+, and Cs+, in K2SO4/nitrate medium which adsorbed as strontium sulphate complex was achieved through ligand- ligan exchange. The elution of strontium carried out via “loading” the column with a solution of 0.03N EDTA in presence of 0.1N NaNO3 at pH7 where Sr2+ has low Kd value. An inductively Coubled Plasma — Optical Emission Spectrometry (ICP — OES) of ARL type model 3520, was used for elemental analysis.  相似文献   
988.
The liquid membrane extraction (MX) and the solvent extraction (SX) of pertechnetate with Aliquat 336 as a carrier has been studied. From the results of SX the percentage of pertechnetate in the inner solution in experiment with LM was proposed. It has been found that the pertraction of pertechnetate depends on the inner solution used and the most effective solutions were those with ClO 4 and SCN. Effects of the carrier concentration in membranes and outer phase composition have been studied too. The results of these experiments were kinetic curves with a minimum, which may be interpreted as a result of competing processes in the systems.  相似文献   
989.
Bases convert 3-(4-substituted phenyl)-4-sulfolenes to 3-aryl-3-sulfolenes, which are subsequently isomerized to 3-aryl-2-sulfolenes. The ratios of the products depend on the character of the substituent in the phenyl ring, and electron-acceptor substituents accelerate the isomerization.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1072–1077, August, 1975.  相似文献   
990.
We perform static light scattering experiments on a dilute suspension of microgel particles and model the resultant form factors Pq by assuming an exponentially decaying dielectric permittivity. The result is that Pq is a Lorentzian function of the scattering wavevector q for length scales greater than the particle size; the width approximately corresponding to twice the particle radius. This simple model reasonably accounts for scattered light from both swollen and shrunken microgel phases.  相似文献   
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