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31.
Ming Xia LI Yan Ming WANG Ru Ru CHEN* Research Institute of Elemento-Organic Chemistry Nankai University Tianjin Pittsburgh University Medical Center Pittsburgh PA U. S. A 《中国化学快报》2001,(6)
The chiral diols ((,(,((,((-Tetraaryl-1,3-dioxolane-4,5-dimethanols) have been used for the formation of cyclic titanates and similar derivatives of Mg, Al and Zr. These complexes of oxophilic metal centers were employed in catalytic and stiochiometric enantioselective reactions such as enantioselective addition reactions of carbon-centered nucleophiles to aldehydes1, [2+2] cycloadditions2, and Diels-Alder reactions3. So far, the two hydrogen atoms of all this type of diols are in trans form… 相似文献
32.
A. Banerjee S. Majumder 《Journal of Contemporary Mathematical Analysis (Armenian Academy of Sciences)》2013,48(6):310-321
With the help of weighted sharing of sets we deal with the problem of unique range set for meromorphic functions with deficient values and obtain a result which improves, generalizes and extends some previous results. We provide two examples to show that the condition in one of our results is the best possible. 相似文献
33.
A. Majumder V. K. Mago A. K. Ray P. T. Kathar A. K. Das 《Applied physics. B, Lasers and optics》2005,81(5):669-674
Two-color, two-step resonant photoionization has been used to produce low-density (∼106 – 107cm−3) barium photoplasma in an atomic beam. The two-photon induced specific absorption coefficient at 355nm for the photoionization process has been measured. The motion of the finite size photoplasma bounded by vacuum is experimentally studied in a static electric field in parallel-plate electrode configuration. It is observed that at sufficiently high electric fields all electrons leave the plasma and the evolution of the left over ion bunch is understood on the basis of independent particle motion. 相似文献
34.
Gobinda Majumder 《Pramana》2004,62(3):587-590
Semileptonic decays ofB →X
u
lv have great importance both from theoretical and experimental point of view, as they are useful for extracting the magnitude
ofV
ub, one of the tiniest elements of CKM matrix. Similarly measurement ofB √ Ds×u can be used to calculateV
ub The Belle Collaboration has measured these branching ratios and extractedV
ub for various theoretical models. 相似文献
35.
We consider diffraction by a semi-infinite crack located alonga fusion interface between two differing elastic media. Twotypes of crack, namely open and partially closed cracks, areinvestigated. An open crack is modelled by a stress-free contactboundary condition and a partially closed crack is modelledby a spring contact boundary condition. For the latter, thejump in the stress across the crack is assumed to be proportionalto the jump in the displacement across the crack. This situationarises in, for example, a K-weld where the fine grain of theparent material (for example, ferritic or forged austeniticsteel) is in stark contrast with the coarse-grained weld metal(for example, austenitic weld metal). In the metal weld thedirection of the grain axis varies through the metal. However,diffraction is a local phenomenon and so the austenitic steelis assumed to have a zonal axis so that it may be modelled bya transversely isotropic composite. The ferritic or forged austeniticsteel will be modelled as an isotropic material. 相似文献
36.
Sonjoy Majumder B. K. Sahoo R. K. Chaudhuri B. P. Das D. Mukherjee 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,41(3):441-445
Ab initio calculations have been carried out to study the magnetic dipole and
electric quadrupole hyperfine structure constants of 205Pb+. Many-body
effects have been considered to all orders using the relativistic coupled-cluster theory in the singles, doubles and partial
triples approximation. The trends of these
effects are found to be different from atomic systems that have been studied
earlier. 相似文献
37.
We derive an expression relating the transport parameter q and the shear viscosity eta of a weakly coupled quark-gluon plasma. A deviation from this relation can be regarded as a quantitative measure of "strong coupling" of the medium. The ratio T{3}/q, where T is the temperature, is a more broadly valid measure of the coupling strength of the medium than eta/s, where s denotes the entropy density. Different estimates of q derived from existing Relativistic Heavy Ion Collider data are shown to imply radically different structures of the produced matter. 相似文献
38.
Mahbubul Majumder Xiaoyue Cheng 《Journal of computational and graphical statistics》2017,26(4):779-780
Donoho’s article “50 Years of Data Science” is a well-thought explanation of a newly developed discipline called “data science.” In this article, we examine his explanations and suggestions about data science, follow-up on some of the issues he mentioned, and share our experiences in developing a data science curriculum and the teaching of related courses. 相似文献
39.
Vargis E Kanter EM Majumder SK Keller MD Beaven RB Rao GG Mahadevan-Jansen A 《The Analyst》2011,136(14):2981-2987
In this paper, we examine how variations in normal tissue can influence disease classification of Raman spectra. Raman spectra from normal areas may be affected by previous disease or proximity to areas of dysplasia. Spectra were acquired in vivo from 172 patients and classified into five tissue categories: true normal (no history of disease), previous disease normal (history of disease, current normal diagnosis), adjacent normal (disease on cervix, spectra acquired from visually normal area), low grade, and high grade. Taking into account the various "normal" states of the tissue before statistical analysis led to a disease classification accuracy of 97%. These results indicate that abnormal changes significantly affect Raman spectra, even when areas are histopathologically normal. The sensitivity of Raman spectroscopy to subtle biochemical differences must be considered in order to successfully implement it in a clinical setting for diagnosing cervical dysplasia and cancer. 相似文献
40.
H. -E. Swoboda F. A. Majumder V. G. Lyssenko C. Klingshirn L. Banyai 《Zeitschrift für Physik B Condensed Matter》1988,70(3):341-348
We investigate and analyze the time-integrated nonlinear optical behaviour of an electronhole plasma in CdS as a function of the temperature and the exciting intensity. The competition between the temperature dependences of the absorption tail and of the manyparticle effects leads with increasing temperature around 160 K to a turn-over from a red- to a blue-shift of the absorption edge under excitation. The frequency dependence of the absorption for high plasma concentrations is in good agreement with theoretical calculations. 相似文献