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1.
The oxodiperoxo complexes of Mo(VI) of the type [MoO(O2)2L], where L = Morpholinomethyl urea, morpholinomethyl thiourea, piperidinomethyl urea, piperidinomethyl thiourea, pyrrolidinomethyl
urea, and pyrrolidinomethyl thiourea have been synthesized and characterized by elemental analysis, molar conductance, IR,
UV-Vis, and TGA/DTA techniques. It is shown that the ligands coordinate to the metal ion in a symmetrical bidentate fashion
through heterocyclic nitrogen and carbonyl oxygen or thiocarbonyl sulfur. Thermal studies indicate continuous weight loss
until a stable oxide is formed.
The text was submitted by authors in English. 相似文献
2.
The transformation of gibbsite have been studied under hydrothermal influence. Results of the X-ray diffraction analysis of the samples heated at different temperatures from 170°C to 265°C are also discussed in detail. The percentage of the boehmite phase formed, due to the transformation of the gibbsite, have been determined by comparing the intensity of the most strongest reflection of the boehmite phase with a fully transformed sample. The activation energy value calculated form X-ray diffractograms is almost comparable with the value calculated from main DTA endotherm of gibbsite.Es wurde die Umwandlung von Gibbsit unter hydrothermalem Einfluß untersucht. Weiterhin werden auch Ergebnisse der Röntgendiffraktionsanalyse an den bei verschiedenen Temperaturen zwischen 170°C und 265°C erhitzten Proben besprochen. Durch Vergleich der Intensität der stärksten Reflexion der Böhmitphase mit einer vollständig umgewandelten Probe wurde der prozentuelle Anteil der während der Umwandlung von Gibbsit gebildeten Böhmitphase bestimmt. Der Wert für die Aktivierungsenergie, berechnet aus den Röntgendiffraktogrammen ist annähernd vergleichbar mit dem aus der DTA von Gibbsit berechneten Wert.
RRL Contribution No. 2028. 相似文献
RRL Contribution No. 2028. 相似文献
3.
Tricyclopentadienyl cerïum(IV) chloride has been treated with various primary and secondary alcohols in benzene medium in the presence of triethylamine to give compounds, (C5H5)3Ce(OR) wherein R may be CH3 C2H3, n-C2H3, iso-C3H7, N-C4H9, iso-C4H9 and iso-C3H11. Infrared spectra and some physical characteristics of all these compounds and reported. 相似文献
4.
5.
H. R. Khajuria S. K. Mehta A. Kalsotra 《Journal of Thermal Analysis and Calorimetry》1987,32(3):749-753
Clay from the Leh area of J&K State (India) was separated into various size fractions by the method of sedimentation and with Sharpie's supercentrifuge process. The results of dilatometric studies of the fractions are discussed in detail.
The authors are grateful to the Director, Regional Research Laboratory, Jammu, for his kind permission to publish this paper. Thanks are also due to Professor G. Mandal, Department of Chemical Engineering, IIT, Bombay, for his suggestions during the study. 相似文献
Zusammenfassung Ton aus dem Leh-Gebiet des J&K Staates (Indien) wurde mittels Sedimentation und nach dem Ultrazentrifugenverfahren nach Sharple in Fraktionen unterschiedlicher Grösse zerlegt. Die Ergebnisse von dilatometrischen Untersuchungen dieser Fraktionen werden detailliert diskutiert.
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The authors are grateful to the Director, Regional Research Laboratory, Jammu, for his kind permission to publish this paper. Thanks are also due to Professor G. Mandal, Department of Chemical Engineering, IIT, Bombay, for his suggestions during the study. 相似文献
6.
M. L. Kaul B. L. Kalsotra R. N. Kapoor 《Journal of Thermal Analysis and Calorimetry》1977,11(1):121-123
The TG curves of dipyridinium complexes of Ce(IV), Th(IV) and Zr(IV) have been reported. The mode of decomposition of the cerium and thorium complexes is broadly comparable but the decomposition of Zr complex shows some variation. 相似文献
7.
Puri S Handa G Kalsotra AK Gupta VK Shawl AS Suri OP Qazi GN 《Journal of chromatographic science》2006,44(4):177-180
St. John's Wort (Hypericum perforatum), a perennial flowering plant, has been used medicinally for thousands of years and has most recently been identified as an effective treatment for mild to moderate depression and neuralgic disorders. This work presents a procedure for the isolation of naphthodianthrones from St. John's Wort by an accelerated extraction and separation of marker compounds by preparative high-performance liquid chromatography (HPLC) with photodiode array detection. The accelerated extraction method minimizes the extraction time and increases the yield, and the marker compounds obtained by preparative HPLC are of 98% purity. The compounds are characterized by liquid chromatography-mass spectrometry (electrospray ionization) and NMR spectra. 相似文献
8.
Copper (II) aryl carboxylates are known to form co-ordination complexes with various oxygen and nitrogen donors such as pyridine-N-oxide1), quinoline and isoquinoline2) diethylamine and dipropylamine1). There is no reference in literature regarding the preparation of complexes of copper (II) aryl carboxylates with 2,6-lutidine. The present communication describes the preparation of complexes of various copper (II) aryl carboxylates with 2,6-lutidine in acetone or ethylacetate medium. 相似文献
9.
Stowers MA van Wuijckhuijse AL Marijnissen JC Scarlett B van Baar BL Kientz CE 《Rapid communications in mass spectrometry : RCM》2000,14(10):829-833
Matrix-assisted laser desorption/ionization (MALDI) mass spectra were obtained from single biological aerosol particles using an aerosol time-of-flight mass spectrometer (ATOFMS). The inlet to the ATOFMS was coupled with an evaporation/condensation flow cell that allowed the aerosol to be coated with matrix material as the sampled stream entered the spectrometer. Mass spectra were generated from aerosol composed either of gramicidin-S or erythromycin, two small biological molecules, or from aerosolised spores of Bacillus subtilis var niger. Three different matrices were used: 3-nitrobenzyl alcohol, picolinic acid and sinapinic acid. A spectrum of gramicidin-S was generated from approximately 250 attomoles of material using a molar ratio of 3-nitrobenzyl alcohol to analyte of approximately 20:1. A single peak, located at 1224 Da, was obtained from the bacterial spores. The washing liquid and extract solution from the spores were analyzed using electrospray mass spectrometry and subsequent MS/MS product ion experiments. This independent analysis suggests that the measured species represents part of the B. subtilis peptidoglycan. The on-line addition of matrix allows quasi-real-time chemical analysis of individual, aerodynamically sized particles, with an overall system residence time of less than 5 seconds. These results suggest that a MALDI-ATOFMS can provide nearly real-time identification of biological aerosols. Copyright 2000 John Wiley & Sons, Ltd. 相似文献
10.
The vanadium(V) peroxo complexes containing Mannich base ligands having composition Na[VO(O2)2(L‐L)]·H2O [where L‐L=morpholinobenzyl acetamide (MBA), piperidinobenzyl acetamide (PBA), morpholinobenzyl benzamide (MBB), piperidinobenzyl benzamide (PBB), morpholinomethyl benzamide (MMB), piperidinomethyl benzamide (PMB), morpholinobenzyl formamide (MBF), piperdinobenzyl formamide (PBF)] have been reported. The complexes have been prepared by stirring vanadium pentoxide with excess of 30% aqueous‐H2O2 followed by treatment with ethanolic solution of the ligand and finally maintained the pH of the reaction mixture by adding dilute solution of sodium hydroxide. The synthesized complexes have been characterized by various physico‐chemical techniques, via elemental analysis, molar conductivity, magnetic susceptibility measurements, infra red, electronic, mass, 1H NMR spectral and TGA/DTA studies. These studies revealed that the synthesized complexes are uni‐univalent electrolytes and diamagnetic in nature. The ligands are bound to metal in a bidentate mode through carbonyl oxygen and the ring nitrogen. Thermal analysis result provides conclusive evidence for the presence of one molecule of lattice water in the complexes. Mass spectra confirm the molecular mass of the complexes. 相似文献