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941.
Coordination Compounds of Aminoacridine-N-oxides with Thiocyanates of the 3d Metals . Reactions of thiocyanates of the 3d metals with selected aminoacridine-N-oxides in homogeneous dilutions of N,N-dimethylformamide form compounds of the type [M(AAcNO)a(DMF)b(NCS)2] · cDMF and [M′(AAcNO)d(DMF)e(NCS)3] · fDMF, M = Mn2+, Co2+, Ni2+, Cu2+, Zn2+; M′ = Cr3+, Fe3+; AAcINO = 3,6-diamino-2,7-dimethylacridin-N-oxide, AAcIINO = 3,6-bis(dimethylamino)acridin-N-oxide, AAcIIINO = 2-ethoxy-6,9-diaminoacridin-N-oxide; a = 1, 2, 3, 4; b = 0, 1; c = 0, 1, 2, 3; d = 1, 2, 3; e = 0, 1, 2; f = 0, 1, 2, 3. The complexes are characterized by IR (4000–200 cm?1) and UV-VIS spectra in solutions and solids and by EPR and conductivity investigations. 相似文献
942.
The Raman spectrum of NH4Cl has been studied as a function of temperature and pressure close to the multicritical point at which the λ-transition changes from first to second order. Variations in the intensities of appropriate bands have been used to calculate the critical exponents for the order parameter. By varying the temperature at fixed pressures of zero, 3.0 k bar and 1.5 k bar, exponent values of β = 0.154 ± 0.012, β = 0.33 ± 0.06 and β = 0.26 ± 0.06 have been obtained for the first-order, second-order and multicritical regions respectively.Our first-order exponent value is close to that observed by previous workers, our second-order value is close to that predicted by the three dimensional Ising model, and our multicritical value is close to that predicted by mean field theory. 相似文献
943.
We have measured serum ferritin level using double antibody radioimmunoassay kit (Eiken ICL) and evaluated the characteristics of the kit and clinical usefulness. Satisfactory results were observed in standard curve, reproducibility, dilution and recovery test. In clinical evaluation, we have measured in normal subjects and patients with various diseases. The range in normal males and females were 13.0-158.7 ng/ml and 7.3-73.0 ng/ml, respectively. Serum ferritin level was elevated in patients with hepatoma, biliary cancer, lung cancer and other malignant diseases. Measurement of serum ferritin value would be useful in the monitoring of cancer patients. 相似文献
944.
The structure and stereochemistry of the cyclopentenolones obtained by condensation of dialkyl ketones with benzil have been studied by NMR spectroscopy. These enolones were converted into cyclopentenones and cyclopentadienes. Alkyl-substituted cyclopentadienes required phenyllithium to effect their conversion by toluenesulphonyl azide into diazo-cyclopentadienes; otherwise piperidine sufficed as base catalyst.2,3,4-Triphenyldiazocyclopentadiene was simply procured by reaction of the condensation product of benzil and phenylacetone with toluenesulphonylhydrazone followed by alkali. Cyclohexyl- and methoxy-triphenylcyclopentadienes were prepared by photolytic decomposition of diazotriphenylcyclopentadiene in cyclohexane or methanol respectively. 相似文献
945.
Product state distributions from low energy He+N2 and N+2He collisions are presented. These data, obtained from collision-produced emission spectra, show severe deviations from Franck-Condon behavior which cannot be solely the result of molecular distortion arising from electrodynamic effects. A model based on consideration of the short-range interaction between the collision partners is proposed. 相似文献
946.
Estimation of the aqueous solubility of organic molecules by the group contribution approach 总被引:1,自引:0,他引:1
Several group contribution methods to estimate the aqueous solubility of organic molecules are proposed and evaluated for their ability to predict the water solubility of new molecules. The learning set consisted of 1168 organic compounds with experimental data taken from the literature after critical evaluation. The best method, based on a new fragment atom scheme, leads to a squared correlation coefficient of 0.95 and an average absolute calculation error of 0.50 log unit, which is superior to other group contribution methods currently available. One of the advantages of this model is that it has upper and lower limits so that the predicted solubilities cannot be unrealistily high or low. 相似文献
947.
Abstract— In dimethylsulfoxide the emission spectrum of luminol chemiluminescence is red-shifted by 300 cm-1 from the photoexcited fluorescence of the product 3-aminophthalate dianion, while in aqueous solvent the two spectra are identical. The spectral properties of the product dianion have been measured in aqueous solvent and in a number of aprotic solvents, both at room temperature and at 77°K. The ground states and the excited states from which emissions are observed are characterized. Two alternatives are presented to explain the aprotic emission spectra. 相似文献
948.
Zusammenfassung Die Eignung einiger tertiärer aromatischer Amine zur Extraktion von Zink aus sauren und neutralen Lösungen wurde untersucht. Man kann diese Amine in drei Gruppen einteilen: solche mit gutem, solche mit schlechtem Extraktionsvermögen und solche, die zwar eine gute Extraktion vortäuschen, die aber tatsächlich als Maskierungsmittel wirken. Die Mehrzahl ist in die zweite Gruppe einzuordnen. In die dritte Gruppe gehören vor allem die Amine 3-(Benzylmethylamino)-propanol, N-Methyl-N-Propargyl-Benzylamin und N-Benzyl-N,N-Dimethyläthylendiamin. 3-(Dimethylamino)-Methylindol in schwach saurem Medium und N,N-Dimethylhomotryptamin im Neutralbereich können als gute Extraktionsmittel für Zink angesehen werden. Nickel wird von den meisten Aminen ganz oder teilweise maskiert.
The extraction of zinc and nickel with tertiary aromatic amines
Summary A study has been made of the suitability of several tertiary aromatic amines for the extraction of zinc from acid and neutral solutions. These amines may be placed in three groups: those with good, those with poor extraction capabilities, and those which simulate a good extraction but in truth act as labelling agents. The majority should be placed in the second category. The third group includes above all the following amines: 3-(Benzylmethylamino)-propanol, N-methyl-N-propargyl-benzylamine and N-benzyl-N,N-dimethylethylenediamine. 3-(Dimethylamino)-methylindole in weakly acid medium and N, N-dimethylhomotryptamine in the neutral region can be looked upon as good extraction agents for zinc. Nickel is entirely or partially masked by most amines.相似文献
949.
The dianthrimide method for the determination of boron in iron and low-alloy steels may be applied to nickel-base materials. The sample is dissolved, without any loss of boron, by hydrochloric and sulphuric acids and the resulting boric acid determined spectrophotometrically with dianthrimide. Background corrections are necessary to compensate for the absorbance from ions such as nickel and iron. 相似文献
950.
A new catalytic oxidation procedure, involving the use of a cerium(IV) sulfate reagent in perchloric acid with a mixed silver(I)—manganese(II) perchlorate catalyst, has been developed for the determination of phosphite, hypophosphite, and tellurium. By this method 15—100 mg of phosphite, 5—35 mg of hypophosphite, and 10—105 mg of tellurium may be determined with standard deviations of ±0.17, ±0.32, and ±0.21% respectively. A direct titration procedure for mercury(I) is described using a ceric perchlorate solution as titrant with the mixed catalyst system. Samples from 65–510 mg may be analyzed with a standard deviation of ±0.36%. 相似文献