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71.
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Complete Separation of ternary mixtures of Ca, Mg and Sr or Ba ions with ammonium chloride and less complete but detectable separation of the same mixtures with ammonium nitrate have been achieved, as well as a few binary separations of the type Ca-Ba, Ca-Sr, Ca-Mg, Mg-Sr and Mg-Ba. 相似文献
74.
Compatibilities of various PVC blends with chlororubber-20 and its graft polyblends have been studied on the basis of our previous findings. It has been found that chlororubber-20 makes compatible blends with PVC, while grafting of styrene, ethyl acrylate or acrylonitrile onto chlororubber-20 generates heterogeneity in their blends with PVC. The behaviour of these blends at the molecular level is reflected in the changes of ultrasonic velocity and absolute viscosity with composition. 相似文献
75.
The Mössbauer spectrum of ferrous zirconium double sulphate FeZrO(SO4)2·8H2O shows a quadrupole split doublet at room temperature. The results are discussed in terms of high-spin Fe(II) in distorted octahedral symmetry. 相似文献
76.
Balwant Singh S. S. Sahota A. S. Narang 《Fresenius' Journal of Analytical Chemistry》1961,182(4):241-244
Summary Copper(II) or Copper(II) and iron(III) in a mixture are determined by titration with EDTA (disodium salt) solution as complexometric reagent at pH 4.0 using potassium thiocyanate-p-anisidine as an indicator.FeIII is estimated in the mixture by titration with EDTA (disodium salt) solution using potassium thiocyanate-ether as an indicator.CuII present in the mixture is, therefore, equivalent to the difference in amounts of the EDTA (disodium salt) used for the two sets of titrations of the mixture using potassium thiocyanate-p-anisidine and potassium thiocyanate-ether as indicators respectively.Strontium, magnesium, manganese, calcium, barium and mercuric ions do not interfere in these estimations.
Zusammenfassung Kupfer(II) oder Kupfer(II) und Eisen(III) zusammen werden komplexometrisch mit ÄDTA-Lösung bei pH 4,0 unter Verwendung von Kaliumthiocyanat-p-Anisidin als Indicator titriert. Eisen(III) wird in dem Gemisch durch komplexometrische Titration gegen Kaliumthiocyanat-Äther als Indicator bestimmt. Der Kupfer(II)-gehalt ergibt sich aus der Differenz der beiden Titrationen. Strontium, Magnesium, Mangan, Calcium, Barium und Quecksilber(II) stören nicht.相似文献
77.
Summary In this paper we have reported our results on the attempted separation of copper(II), nickel(II), cobalt(II) and iron(III) in mixtures by filter paper strip chromatography, using aqueous ethanol as solvent. The effect of the presence of varying concentrations of citrate ion as a complexing agent in the mixtures has been studied. The complexing agent has been added in the metal solution, and not in the solvent as usually done by previous workers. 相似文献
78.
Photochemical and thermal transformations of carboxylic dithiocarbamic anhydrides and acyl xanthates
The reaction of diphenylchloroacetyl chloride with different dithiocarbamates gave the corresponding dithiocarbamic anhydrides. Under analogous conditions, dithiocarbamyl phenylacetic acids and dithiocarbamyl acetic acids were formed from the reaction of dithiocarbamates with phenylchloroacetyl chloride and chloroacetyl chloride, respectively. O-Ethyl S-acyl xanthates were formed from the reaction of potassium O-ethyl xanthate with diphenylacetyl chloride, diphenylchloroacetyl chloride, cyclopentylphenylacetyl chloride and triphenylacetyl chloride. Photolysis of dithiocarbamic anhydrides gave a mixture of products consisting of 1,2-dichlorotetraphenylethane, carbon monoxide and the corresponding thiocarbamoyl sulfides. Acyl xanthates, on the other hand, gave carbon monoxide and the corresponding substituted ethane derivatives. When dithiocarbamic anhydrides were refluxed in hydroxylic solvents such as methanol, ethanol and n-propanol, the corresponding dithiocarbamyl acetates were formed. Thermal decomposition of acyl xanthates gave carbon disulfide and the corresponding esters. 相似文献
79.
Thiotropolone forms chloroform-soluble reddish-brown and violet complexes with cobalt(II) and nickel(II), in the pH range 7.0-8.5 and 6.0-9.0 respectively. Based on this, a sensitive and rapid method for the spectrophotometric determination of traces of cobalt and nickel in metals and alloys has been developed. The two metals can be determined accurately in the range 0.6-2.6 ppm of cobalt and 0.75-4.57 ppm of nickel, simultaneously. 相似文献
80.
In this review, the applications of beta galactosidase complementation are described. alpha Complementation is a naturally occurring process in bacteria and in engineered cells, and can also occur in eukaryotic cells. Two forms of alpha complementation have been used in high throughput screening (HTS), in which interacting fragments complement with either low or high affinity. Low affinity complementation is used to monitor protein protein interactions, such as those occurring in homodimerization of the epidermal growth factor receptor (EGFR), and provides a robust screen for detection of EGFR inhibitors. High affinity complementation provides the basis for several HTS assays, in which analytes, such as cAMP or IP(3), are detected in crude cell lysates. A development of the latter approach is protein labeling, providing for measurement of cell protein expression and trafficking. Collectively, the use of beta galactosidase complementation provides a novel and flexible technology for highly sensitive, homogeneous HTS assay development. 相似文献