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101.
Fine powder of KI was coloured in an electrodeless discharge. Due to quick bleaching of the F centres produced in this method,
it was possible to prepare the samples that were almost free from the F centres. High concentration of the electron deficient
centres could be produced, which were studied by measuring the diffused reflectance. A band at 354 nm is shown to be composed
of two overlapping bands. Further, growth of a band appearing at 265 nm is studied. Bleaching characteristics of the samples
are studied and it is shown that, similar to F centre bleaching, bleaching of these samples also proceeds in at least two
steps. The difference between two components of the bleaching curves is quite marked. Further it is showed that the components
are related to the presence of different absorption bands and appear at different stages of colouration. 相似文献
102.
A comparative study ofγ-ray colouration and electrodeless discharge excitation is reported for NaF. New absorption bands and glow peaks were found.
These are shown to be characteristic of electrodeless discharge method of colouration. These are attributed to the multiple
types of defects. Further, it is shown that the process by which such defects are formed is strongly temperature dependant.
A tentative explanation for the peculiar characteristic of the electrodeless discharge excitation is put forth. The possibility
of exploiting these peculiarities for the study of certain properties of colour centres is pointed out. 相似文献
103.
104.
105.
Rajnikant Dinesh Mousmi M.B. Deshmukh S.S. Patil Anshu Sawhney 《Journal of chemical crystallography》2004,34(10):693-696
The three-dimensional molecular and crystal structure of 2-(2'-propanonylthio)3-(o-methyl phenyl)quinazol-4(3H)-one has been determined by X-ray crystallographic methods. This compound crystallizes in the orthorhombic space group Pbca with unit cell parameters: a=9.649(5), b=30.102(10), c=11.403(9)Å. It has been solved by direct methods and refined to a residual index of 0.054. The magnitude of torsion along C16— C11— N3— C4 bond is 93.5(4)°. The dihedral angle between the plane comprising all the ring atoms of quinazoline moiety and the atoms of the methyl substituted phenyl ring is 94.12(1)°. The crystal structure is stabilized by one intramolecular C— HsO interaction and three intermolecular C— HsN contacts. 相似文献
106.
Nishant D. Kambli V. Mageshwaran Prashant G. Patil Sujata Saxena Rajendra R. Deshmukh 《Cellulose (London, England)》2017,24(12):5355-5369
In the present study low cost microcrystalline cellulose (MCC) powder was prepared from cornhusk fibres, extracted chemically followed by anaerobic consortium treatment. Cornhusk fibres were treated with 10% alkali at 120 °C for 60 min followed by anaerobic consortium treatment for 3 days. It was then bleached with hydrogen peroxide and finally washed. Bleached pulp was hydrolysed using 4 N HCl to get the MCC. In the present investigation, we have characterized the MCC prepared from cornhusk fibres thoroughly for its physico-chemical properties and compared with Avicel®-PH 101, a commercial grade MCC. Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Powder Diffraction (XRD) and Differential Scanning Calorimetry (DSC) were used for characterization of samples. Similarly the powder and flow properties of the MCC prepared from cornhusk fibres were also investigated and the results were compared with Avicel®-PH 101. Our results showed that various properties and the purity of MCC prepared from cornhusk fibres are comparable to the commercial grade MCC. Since, cornhusk is an agricultural waste product, MCC obtained from cornhusk fibres will be from cheaper raw materials than current market MCC. 相似文献
107.
Deshmukh Amarsinh R. Bhosle Manisha R. Khillare Lalit D. Dhumal Sambhaji T. Mishra Akansha Srivastava Arvind K. Mane Ramrao A. 《Research on Chemical Intermediates》2017,43(2):1107-1120
Research on Chemical Intermediates - We report synthesis and in vivo antihyperglycemic evaluation of new 3-substituted... 相似文献
108.
109.
A simple and efficient protocol developed for the synthesis of 5-substituted 1H-tetrazole derivatives through [2+3] cycloaddition reaction between benzonitriles and sodium azide using diisopropylethylammonium acetate as a recyclable reaction medium is described. The reactions proceed well at 80?°C and provide the corresponding tetrazoles in good to excellent yields (up to 94% yield). Developed method has notable advantages, such as simple and mild conditions, easy workup, reusability with consistent catalytic activity, and safer alternative to hazardous, corrosive conventional Lewis acid catalysts. 相似文献
110.
Yogesh S. WaghDinesh N. Sawant Kishor P. DhakeKrishna M. Deshmukh Bhalchandra M. Bhanage 《Tetrahedron letters》2011,52(43):5676-5679
Simple methodology for the allylation of various N- and O-pronucleophiles with 1-phenyl-1-propyne as an allylating agent, using PS-TPP-Pd (polymer supported triphenylphosphine palladium) as a highly active heterogeneous recyclable catalyst has been developed. The protocol is applicable for a wide variety of hindered and functionalized aromatic amines, alcohols, and carboxylic acids. The catalyst exhibited remarkable catalytic activity for five consecutive recycles. 相似文献