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101.
Titanium(IV) alkyl xanthates of the types CpTi(S2COR)Cl2, CpTi(S2COR)2Cl and CpTi(S2COR)3, where R = CH3, C2H5, C3H7, C4H9 and C5H11, have been prepared by the reaction of monocyclopentadienyl titanium(IV) trichloride with potassium alkyl xanthates in anhydrous dichloromethane. Conductance and infrared studies suggest that these complexes are non-electrolytes in which all of the xanthate ligands are bidentate. Proton nmr spectra of these complexes indicate that there is rapid rotation of the cyclopentadienyl ring about the metal-ring axis and for the CpTi(S2COR)3 complexes non-equivalence of the alkylxanthate ligands was observed. 相似文献
102.
Using hodograph and Legendre transformation functions the basic equations are recast in terms of this function, and the conditions which this function should satisfy are stated. Several applications of this method are considered, and the geometry of magnetic field lines is discussed. 相似文献
103.
D. B. Parihar Om Prakash Indira Bajaj R. P. Tripathi K. K. Verma 《Mikrochimica acta》1971,59(3):393-398
Summary High explosives having the sameR
f
values on a thin-layer chromatogram and difficult to separate are readily resolved as their coloured -complexes with aromatic amines. After liberation from their complexes on the plate, up to 1.5 g of the explosives can be conveniently estimated at their characteristic absorption maxima.
Zusammenfassung Hochexplosive Substanzen mit gleichenR f -Werten auf Dünnschichtchromatogrammen, die sich schlecht trennen lassen, werden als gefärbte -Komplexe mit aromatischen Aminen gut voneinander getrennt. Nach Freisetzung aus den Komplexen auf der Platte können bis zu 1,5 g der Explosivstoffe bei ihrem charakteristischen Absorptionsmaximum auf übliche Weise bestimmt werden.相似文献
104.
Sandeep Mishra Sarvpreet Kaur S. K. Tripathi C. G. Mahajan G. S. S. Saini 《Journal of Chemical Sciences》2006,118(4):361-369
We present here infrared absorption spectra of dithia tetraphenylporphine and its cation in the 450–1600 and 2900–3400 cm−1 regions. Most of the allowed IR bands are observed in pairs due to overallD
2h
point group symmetry of the molecule. The observed bands have been assigned to the porphyrin skeleton and phenyl ring modes.
Some weak bands, which are forbidden underD
2h
, also appear in the spectra due to the distortion of the molecule from planarity-caused by the out-of-plane positioned N
and S atoms. Increased intensity of some phenyl ring bands compared to free-base tetraphenylporphine is explained on the basis
of rotation of phenyl rings towards the mean molecular plane. Contrary to the point group symmetry of cation of dithia tetraphenylporphine,
certain bands are observed to be degenerate due to identical bonding arrangements in pyrrole rings of the cation 相似文献
105.
Ramachandran K. Tripathi V.K. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1998,26(2):141-144
Near the critical layer, a large-amplitude laser beam creates a transverse plasma channel due to the ponderomotive force. The axis of the channel is normal to the ambient density gradient. Inside the channel, the laser beam decays into counter-propagating ion acoustic and Langmuir waves. A nonlocal theory of the process is developed for a parabolic density profile. The growth rate of the instability is significantly reduced due to the nonlocal effects 相似文献
106.
107.
The Coulomb-Glauber approximation is applied to evaluate the electron-impact excitation integrated cross sections for 11
S —n
1
P (n=2, 3) transitions in helium-like ions, C4+, N5+, O6+ and Ne8+. The results are presented in terms of scaled collision strengthn
3
Z
2
k
i
2
σ and scaled integrated cross-sectionZ
4σ. Our values when compared with other available theoretical results are found to be larger than the Coulomb-Born and distorted
wave polarised orbital (DWPO) values. 相似文献
108.
The effective interaction W which was recently deduced empirically from saturation considerations as an addition to the Sussex matrix elements is compared with earlier estimates of corrections arising from an assumed short-range repulsion and from the tensor force in second order. 相似文献
109.
M. S. Sodha S. Prasad V. K. Tripathi 《Applied Physics A: Materials Science & Processing》1974,3(3):213-216
On the basis of perturbation theory, the phenomenon of nonlinear self distortion of an electromagnetic pulse (Gaussian in time) in a collisional plasma has been studied. The nonlinearity appears through the modulation of electron collision frequency by the power absorption from the wave. At moderate energies of the pulse, considerable distortion in the amplitude envelope has been predicted. 相似文献
110.
The phonon frequencies of platinum are calculated using a model potential approach. The results are in fair agreement with the experimental data but do not show any Kohn anomaly or any kink, as revealed experimentally. The magnitude of the anomaly has been theoretically estimated and comes out to be very small. 相似文献