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31.
Y.N. Joshi K.S. Bhatia W.E. Jones 《Spectrochimica Acta Part B: Atomic Spectroscopy》1973,28(4):149-155
The third and fourth spectra of gallium have been photographed in the region 6000–400 Å by using a 3-m normal-incidence, vacuum spectrograph and a 3.5-m Ebert spectrograph. A three-electrode vacuum spark and a spark in helium were used as sources. New measurements for the wavelengths have confirmed earlier work and provided material to extend the analysis of Ga III and Ga IV. 相似文献
32.
Adams J Aggarwal MM Ahammed Z Amonett J Anderson BD Arkhipkin D Averichev GS Badyal SK Bai Y Balewski J Barannikova O Barnby LS Baudot J Bekele S Belaga VV Bellwied R Berger J Bezverkhny BI Bharadwaj S Bhasin A Bhati AK Bhatia VS Bichsel H Billmeier A Bland LC Blyth CO Bonner BE Botje M Boucham A Brandin AV Bravar A Bystersky M Cadman RV Cai XZ Caines H Calderón de la Barca Sánchez M Carroll J Castillo J Cebra D Chajecki Z Chaloupka P Chattopdhyay S Chen HF Chen Y Cheng J Cherney M Chikanian A 《Physical review letters》2004,93(25):252301
Results on high transverse momentum charged particle emission with respect to the reaction plane are presented for Au + Au collisions at square root s(NN)=200 GeV. Two- and four-particle correlations results are presented as well as a comparison of azimuthal correlations in Au + Au collisions to those in p + p at the same energy. The elliptic anisotropy v(2) is found to reach its maximum at p(t) approximately 3 GeV/c, then decrease slowly and remain significant up to p(t) approximately 7-10 GeV/c. Stronger suppression is found in the back-to-back high-p(t) particle correlations for particles emitted out of plane compared to those emitted in plane. The centrality dependence of v(2) at intermediate p(t) is compared to simple models based on jet quenching. 相似文献
33.
Nair VA Mustafa SM Mohler ML Fisher SJ Dalton JT Miller DD 《Tetrahedron letters》2004,45(51):9475-9477
A series of optically active nonsteroidal selective androgen receptor modulators with structures analogous to bicalutamide was prepared by replacing the trifluoromethyl group with iodine and the sulfonyl linker by oxygen. 相似文献
34.
Bachhawat P Mishra S Bhatia Y Bisaria VS 《Applied biochemistry and biotechnology》2004,118(1-3):269-282
The biosynthetic activity of yeast Pichia etchellsii β-glucosidase II (BglII) expressed in recombinant Escherichia coli was utilized for synthesis of cellooligosaccharides, alkyl and terpene glucosides. Cellooligosaccharides with a degree of
polymerization of 3 and greater were resolved by thin-layer chromatography (TLC) using an ethyl acetate: 1-propanol:2-propanol:water
(8:5:1:1) solvent system followed by visualization with 0.2% naphthoresorcinol reagent. Using 2M cellobiose and 15 IU of partially purified BglII, 57 mmol/L of oligosaccharides (comprising mostly cellotriose and cellopentaose) was synthesized in 16 h. Similarly, alkyl
glucosides with chain lengths from 6 to 10 carbons were synthesized and products extracted to near purity by ethylacetate
extraction. The same extraction method was employed to separate, to near purity, various monoterpenyl (nerol, geraniol, citronellol)
glucosides. A reliable and simple method for separation of cellooligosaccharides using a combination of Bio-Gel P-2 gel filtration
and charcoal celite adsorption chromatography was developed. The cellooligosaccharides were separated to purity as confirmed
by TLC. The enzyme was among the very few that could synthesize a wide variety of glycoconjugates. 相似文献
35.
We present a theory for the transport of molecules adsorbed in slit and cylindrical nanopores at low density, considering the axial momentum gain of molecules oscillating between diffuse wall reflections. Good agreement with molecular dynamics simulations is obtained over a wide range of pore sizes, including the regime of single-file diffusion where fluid-fluid interactions are shown to have a negligible effect on the collective transport coefficient. We show that dispersive fluid-wall interactions considerably attenuate transport compared to classical hard sphere theory. 相似文献
36.
Nelson ML Ismail MY McIntyre L Bhatia B Viski P Hawkins P Rennie G Andorsky D Messersmith D Stapleton K Dumornay J Sheahan P Verma AK Warchol T Levy SB 《The Journal of organic chemistry》2003,68(15):5838-5851
A diverse collection of tetracycline derivatives has been synthesized utilizing Heck, Suzuki, and other palladium-coupling reactions via tetracycline arenediazonium and iodoarene salts. Large numbers of tetracyclines are now possible via these reactions, including numerous upper periphery derivatives of doxycycline, minocycline, sancycline, and methacycline modified at positions C7, C9, and C6-C13 on the tetracycline naphthacene ring. Application of palladium-coupling reactions to the tetracyclines has yielded new tetracycline classes with differing structural attributes, greatly increasing the structural diversity of this family of antibiotics, one of the last of the early antibiotic families to be expanded by organic and medicinal chemistry. 相似文献
37.
An infinitely extending homogenous partially ionized plasma endowed with several physical mechanisms and permeated by a variable magnetic field is considered. The combined effect of these parameters, namely, Hall currents, finite conductivity, ion viscosity, collision with neutrals and thermal conductivity on the gravitational instability of the plasma is studied. It is found that the several mechanisms play different physical roles in the perturbed problem. Jeans' Criterion is analyzed in the framework of Tsallis' statistics for possible modifications due to the presence of nonextensive effects. A simple generalization of the Jeans' criterion is obtained and the standard values are obtained in the limiting case q = 1, q being the nonextensive parameter. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
38.
The II-VI compound semiconductor, ZnSe having wide band gap between 2.58 and 2.82 eV is a promising material for use in photovoltaic devices, blue light emitting diodes and laser diodes. Several methods have been used to prepare ZnSe thin films. We have deposited ZnSe films on ultra-clean glass substrate by sintering technique. The optical, structural and electrical properties of ZnSe thin films have been examined. The optical band gap of these films is studied using reflection spectra in wavelength range 325-600 nm and structure of these films is studied using XRD. The DC conductivity of the films was measured in vacuum by two-probe technique.Sintering is a very simple and viable method compared to other intensive methods. The results of the present investigation will be useful in characterizing the material ZnSe for its applications in photovoltaics. 相似文献
39.
Smita A Ghanekar Sonny Bhatia Joyce J Ruitenberg DeLa Corazon Rosa Mary L Disis Vernon C Maino Holden T Maecker Cory A Waters 《Journal of immune based therapies and vaccines》2007,5(1):7-14
Background
Monocyte-derived-dendritic-cells (MDDC) are the major DC type used in vaccine-based clinical studies for a variety of cancers. In order to assess whether in vitro differentiated MDDC from cryopreserved PBMC of cancer patients are functionally distinct from those of healthy donors, we compared these cells for their expression of co-stimulatory and functional markers. In addition, the effect of cryopreservation of PBMC precursors on the quality of MDDC was also evaluated using samples from healthy donors. 相似文献40.
Poly(methyl methacrylate)-supportedβ-diketone-linked palladium complexes on refluxing with olefins at 70°C in methanol-water medium for 10 h afforded carbonyl
compounds. The course of the reaction was found to be influenced by the degree of cross-linking of the polymer matrix and
the structural environment of the ligand. The reaction is assumed to proceed through a hydroxy palladation intermediate. A
suitable mechanism is also suggested. 相似文献