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101.
102.
N. Nagaraj M. C. Shastry P. G. Vaidya 《The European physical journal. Special topics》2008,165(1):73-83
The direct measurement of the gluon polarization in the nucleon at the COMPASS experiment is discussed. Three complementary
analyses are considered. All of them study ΔG/G using method based on selection of events originating from the Photon Gluon Fusion process. Most precise preliminary value
of ΔG/G is obtained from the high p
T
pair channel for the Q
2 < 1 (GeV/c)2 region: ΔG/G = 0.016 ± 0.058 (stat.) ± 0.055 (syst.).
on behalf of the COMPASS collaboration 相似文献
103.
Panov VP Nagaraj M Vij JK Panarin YP Kohlmeier A Tamba MG Lewis RA Mehl GH 《Physical review letters》2010,105(16):167801
Hydrocarbon linked mesogenic dimers are found to exhibit an additional nematic phase below the conventional uniaxial nematic phase as confirmed by x-ray diffraction. The phase produces unusual periodic stripe domains in planar cells. The stripes are found to be parallel to the rubbing direction (in rubbed cells) with a well-defined period equal to double the cell gap. The stripes appear without external electromagnetic field, temperature or thickness gradients, rubbing or hybrid alignment treatments. Simple modeling proposes a negative sign for at least one of the two elastic constants: splay and twist, as a necessary condition for the observed pattern. 相似文献
104.
Lesaw Siero B. Nagaraj B. Prabhuswamy H. S. Yathirajan P. Nagaraja R. S. Narasegowda S. L. Gaonkar 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):o821-o823
The title compound (systematic name: {2‐butyl‐4‐chloro‐1‐[2′‐(2‐trityl‐2H‐tetrazol‐5‐yl)biphenyl‐4‐ylmethyl]‐1H‐imidazol‐5‐yl}methanol), C41H37ClN6O, crystallizes in the centrosymmetric space group P with two independent molecules in the asymmetric unit. These molecules differ significantly only in the relative orientations of the rings in the biphenylyltetrazole moieties. One of the molecules shows disorder for three C atoms in the n‐butyl group. Hydrogen bonds link the molecules in an infinite chain along the a axis. 相似文献
105.
106.
Monogioudis P. Conner K. Das D. Gollamudi S. Lee J.A.C. Moustakas A.L. Nagaraj S. Rao A.M. Soni R.A. Yifei Yuan 《Communications Magazine, IEEE》2004,42(10):28-39
This article outlines the development of intelligent antenna (IA) solutions for UMTS, a third-generation W-CDMA system. Since the selection of an antenna configuration paired with realizable uplink/downlink algorithms that can satisfy all operating environments is a broad task, this article focus is on cost-effective antenna arrays for macrocells. Algorithms that exploit the antenna configurations and act at both the physical and MAC layers are highlighted and supported by simulation results. Two solutions stand out for UMTS: a universal beamforming algorithm that unifies user-specific and fixed beamforming under one framework, and multibeam scheduling (MBS) that significantly increases downlink packet data throughput using the concept of code reuse in conjunction with beamforming. The article summarizes the critical issues that were faced in the development of an IA solution capable of delivering the theoretically promised benefits to end users. 相似文献
107.
Cherkupally Sanjeeva Reddy Adki Nagaraj 《中国化学快报》2007,18(12):1431-1435
An efficient route for the synthesis of 5-(arylpropenylidine)-2,4,6-pyrimidinetrione 3 from an appropriateα,β-unsaturated aromatic aldehydes 1 and barbituric acid 2 under both non-catalytic and solvent-free microwave irradiation conditions was described.In this way,a range of biologically important compounds 3 was obtained in good to excellent yields (86-98%) in a very short reaction time (30-80s). 相似文献
108.
LetY be a smooth projective curve degenerating to a reducible curveX with two components meeting transversally at one point. We show that the moduli space of vector bundles of rank two and odd
determinant on Ydegenerates to a moduli space onX which has nice properties, in particular, it has normal crossings. We also show that a nice degeneration exists when we fix
the determinant. We give some conjectures concerning the degeneration of moduli space of vector bundles onY with fixed determinant and arbitrary rank. 相似文献
109.
The complex relative permittivity of a non-crystallizable secondary alcohol, 5-methyl-2-hexanol, is measured over a wide range of temperatures and pressures up to 1750 MPa (17.5 kbar). The data at atmospheric pressure (P = 0.101 MPa) are analyzed in terms of three processes, and the results are in complete agreement with that of O. E. Kalinovskaya and J. K. Vij [J. Chem. Phys. 112, 3262 (2000)]. Process I is of the Debye type and process II is of the Davidson-Cole type, whereas process III is identified as the Johari-Goldstein relaxation process. For pressures of ~500 MPa and higher, processes I and II are seen to merge into each other to form a single dominant process which unambiguously cannot be resolved into more than one process. The dielectric relaxation strength of process I decreases slightly initially with pressure and when the two processes have merged at elevated pressures, the total relaxation strength increases with increase in pressure. Process III is better resolvable at higher pressures especially above T(g) in the supercooled liquid state for the reason that the separation in the time scales between the dominant and the JG relaxation process increases at elevated pressures. Surprisingly we find a change in the slope in the plot of log τ(JG) vs. 1/T for P = 1750 MPa. The results for the relaxation time of alcohols are compared with the Kirkwood correlation factor, g, and it is found that higher is the g, lower is the relaxation time for process I, and it is more of the Debye type. On a reduction in g brought about by an increase in pressure at lower temperatures, the dominant process becomes non-Debye though extensive hydrogen bonding is still present. The dielectric strength of the merged processes increases with increase in pressure. The values of the steepness index, m = |d log τ/d(T(g)/T)|(T = Tg) for processes I and II are different for P = 0.1 MPa. However the value of m, for the composite process, which is a merger of processes I and II, for P = 1750 MPa is almost the same for process II at P = 0.1 MPa. From the results of the activation volume, activation enthalpy, and a comparison of the relaxation times with the g factor, we conclude that both processes I and II are significantly affected by hydrogen bonding and both contribute to the structural relaxation. 相似文献
110.
B. R. Nagaraj 《偏微分方程通讯》2013,38(3-4):547-575