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1.
Beeranahally H Doreswamy Madegowda Mahendra Hirihally C Devarajegowda Venkatesh B Devaru Sridhar M Anandalwar Javaregowda S Prasad 《Analytical sciences》2004,20(2):407-408
The title compound was extracted from a natural product and its structure was characterized by an X-ray diffraction method. It crystallizes in the tetragonal space group P41 with cell parameters a = 15.832(10)A, c = 11.622(10)A, Z = 4; the final residual factor is R1 = 0.0769. The structure has both intra and intermolecular hydrogen bonds. 相似文献
2.
Additive-subtractive phase modulated speckle interferometry (ASPMSI) is a technique that minimizes the susceptibility of speckle methods to environmental noise while providing fringes of good visibility. The method requires the acquisition of two consecutive video frames of additive-speckle images of the same two deformed states of an object at a rapid enough rate such that ambient noise is not a problem. The additive-speckle images as expected are of very poor visibility due to the presence of the self-interference term. An interframe phase-modulation is introduced and the two additive-speckle images are digitally subtracted to improve the fringe visibility by removing the self-interference term. The ASPM-SI method works with in-plane and out-of-plane deformation sensitive ESPI as well as with displacement-gradient sensitive speckle-shearing interferometry. It is shown that the ASPM-SI scheme has higher visibility than conventional additive-SI and performs consistently better than subtractive-SI schemes in the presence of partial interframe speckle decorrelating optical noise. Furthermore, it is shown that the fringe visibility of the out-of-plane displacement sensitive interferometer which uses a protected reference beam separate from the object beam can be made to be essentially unity even at complete interframe decorrelation. 相似文献
3.
K. Ravikumar B. Sridhar M. Mahesh V. V. Narayana Reddy 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):o574-o576
The crystal structures of pyranoquinolines 9‐fluoro‐5‐phenyl‐3,4,4a,5,6,10b‐hexahydro‐2H‐pyrano[3,2‐c]quinoline, C18H18FNO, and 9‐methyl‐5‐phenyl‐3,4,4a,5,6,10b‐hexahydro‐2H‐pyrano[3,2‐c]quinoline, C19H21NO, are isomorphous. In both structures, the pyran ring is exo to the six‐membered N‐heterocyclic ring formed in the cycloaddition step. The torsion angles across the phenyl linkage for the two structures are −91.2 (1) and −88.3 (2)°. The striking feature in both crystal packings is that they do not contain the expected conventional hydrogen bonds, in spite of the presence of good hydrogen‐bonding functionalities. Possible C—H⋯π interactions are, however, observed. 相似文献
4.
Sunanda Banerjee Rohini M Godbole Sreerup Raychaudhuri Ben Allanach Sunanda Banerjee Satyaki Bhattacharyya Debajyoti Choudhury Siba Prasad Das Anindya Datta Rohini M Godbole Monoranjan Guchait Sabine Kraml Gobinda Majumdar David Miller Margarete Mühlleitner Nobuchika Okada Maxim Perelstein Santosh K Rai Sreerup Raychaudhuri Saurabh D Rindani DP Roy K Sridhar Rishikesh Vaidya D Zeppenfeld 《Pramana》2006,67(4):617-637
This is summary of the activities of the working group on collider physics in the IXth Workshop on High Energy Physics Phenomenology
(WHEPP-9) held at the Institute of Physics, Bhubaneswar, India in January 2006. Some of the work subsequently done on these
problems by the subgroups formed during the workshop is included in this report. 相似文献
5.
Hadroprduction ofJ/ψ in π? nucleus collisions is studied in the context of the colour singlet model using nuclear structure functions from three different models of the EMC effect. We conclude that it is possible to understand the data on the large transverse momentum (p T ) and small Feynmanx (x F ) of theJ/ψ in terms of the nuclear dependence of structure functions alone. We further show that these data can be used to distinguish between different models of the EMC effect, and that a study of distributions in various kinematic variables in photoproduction ofJ/ψ should be able to very effectively supplement the information obtained from hadroproduction experiments. 相似文献
6.
Electrochemical oxidation of thio/carbohydrazide and their hydrazone derivatives Benzaldehyde thiocarbohydrazone [BTCH] diacetylene
thiocarbohydrazone [DATCH] have been studied in Brit-ton Robinson buffer in aqueous and nonaqueous media at a glassy carbon
electrode. The effects of pH, sweep rate, concentration, temperature and surfactants have been studied. The complex bis (carbo/thiocabohydrazide) Zn(II) chloride was also subjected to voltammetric analysis in order to understand the reactivity
both in free and metal bound states. The reaction conditions were optimized for the determination of above compounds in micrograms
quantities by differential pulse voltammetry, analytical utility of this investigation is also highlighted. 相似文献
7.
V. Mahadevan S. Padma M. Srinivasan 《Journal of polymer science. Part A, Polymer chemistry》1981,19(6):1409-1419
A new class of polyhydrazides having aromatic as well as aliphatic units has been synthesized by low-temperature solution polycondensation from equimolar amounts of diacid chloride and dihydrazides in HMPT as solvent. These polyhydrazides have poor solubilities and their intrisnsic viscosities ranged from 0.2 to 0.6 dl/g. X-ray diffractograms of these polyhydrazides show that the polymers having terephthalic acid dihydrazide unit were more crystalline and all the polymers have densities in the range of 1.2-1.8 g/cm3. Thermogravimetric analysis of these polyhydrazides showed initial weight losses commencing at 220–300°C in both air and nitrogen. 相似文献
8.
9.
Propargyloxycarbonyl (Poc) as a protective group for the hydroxyl function in carbohydrate synthesis
[reaction: see text] The propargyloxycarbonyl (Poc) group can be used for the selective protection of the hydroxyl function in carbohydrates and can be removed under neutral conditions using tetrathiomolybdate MoS(4)(2-) (1) in CH(3)CN at room temperature. Under the conditions of deprotection benzylidine acetals, benzyl ethers, acetyl and levulinoyl esters, and allyl and benzyl carbonates are left untouched. It has also been shown that the new protective group (Poc) is compatible with acidic, basic, and also glycosylation conditions. 相似文献
10.
A. Mahammad Ibrahim V. Mahadevan M. Srinivasan 《Journal of polymer science. Part A, Polymer chemistry》1981,19(3):687-693
Novel poly(N-oxyimide)s (PNOI) were synthesized by the room temperature polycondensation of N,N′-dihydroxypyromellitimide (I) with dichloro compounds in N,N-dimethylformamide (DMF) in the presence of triethylamine both as base as well as catalyst. The dichloro compounds used were 1,4-bis(chloromethyl)-2,5-dimethylbenzene (II), 1,5-bis(chloromethyl)-2,4-dimethylbenzene (III), 1,4-bis(chloromethyl)-2,5-dimethoxybenzene (IV) and 1,4-dichlorobut-2-yne (V). Polymer synthesis, characterization, and properties such as density, viscosity, solubility, crystallinity, and thermal stability were described. Two model compounds, viz. (i) MNOI-1 from N-hydroxyphthalimide and a dichloro compound (III), (ii) MNOI-2 from I and benzyl chloride were also synthesized to confirm the formation of polymers. The polymers thus obtained had high intrinsic viscosities in the range 1.09–1.18 dl/g. The thermal decomposition of the polymers started around 260°C with 20–25% decomposition and about 50% weight loss was observed at 400°C. 相似文献