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101.
The wide-range physics program of the P?ANDA experiment requires detectors which have to combine state-of-the-art and novel techniques in particle measurements and data-readout. The central straw tube tracker (STT) in the P?ANDA target spectrometer features a high-resolution spatial and momentum reconstruction of charged particle trajectories, a measurement of the specific energy-loss for particle identification, together with a minimal material budget by the technique of self-supporting straw layer modules. The STT is essential for the online track reconstruction and event identification in the continuous, triggerless data-acquisition at P?ANDA. This paper summarizes the detector design, test system and simulation results, and the time lines of the STT construction. 相似文献
102.
LHC Higgs Cross Section Working Group A. Denner S. Heinemeyer I. Puljak D. Rebuzzi M. Spira 《The European Physical Journal C - Particles and Fields》2011,71(9):1753
We present an update of the branching ratios for Higgs-boson decays in the Standard Model. We list results for all relevant
branching ratios together with corresponding uncertainties resulting from input parameters and missing higher-order corrections.
As sources of parametric uncertainties we include the masses of the charm, bottom, and top quarks as well as the QCD coupling
constant. We compare our results with other predictions in the literature. 相似文献
103.
A multiwavelength Brillouin/erbium fiber laser (BEFL) with low threshold power is realized. A low threshold power of 3 mW and a wide tuning range of 18 nm can be achieved by controlling the reflected power in the nonlinear optical loop mirror (NOLM). Up to 24 lines with a wavelength spacing of 0.086 nm are generated at the Brillouin pump and at the 1 480-nm pump with 0.5 dBm (0.9 mW) and 25 mW of power, respectively. 相似文献
104.
报道了一种热转印色带用黄染料的1H、13C NMR , 应用1H NMR、13C NMR、定量碳谱、DEPT、1H-1H COSY、HMQC、HMBC等确定了其在氘代氯仿中的分子结构, 并对全部谱峰进行了归属, 探索了黄染料在氘代氯仿中的结构对13C、1H NMR谱图化学位移及谱峰裂分的影响. 相似文献
105.
Two new C-glucoside oxanthrones,6-methoxyl-10-hydroxyaloin A(1) and 6-methoxyl-10-hydroxyaloin B(2),were isolated from the roots of Rumex gmelini Turcz.Their structures were elucidated on the basis of spectroscopic techniques and chemical means. 相似文献
106.
Ida K Inagaki S Sakamoto R Tanaka K Funaba H Takeiri Y Ikeda K Michael C Tokuzawa T Yamada H Nagayama Y Itoh K Kaneko O Komori A Motojima O;LHD Experimental Group 《Physical review letters》2006,96(12):125006
A new slow transition process for energy transport in magnetically confined plasmas is reported. The slow transition is characterized by the change between two metastable transport conditions characterized by a weak and a strong electron temperature (Te) dependence of normalized heat flux. These two branches are found to merge at the critical gradient. In metastable transport, the derivative of normalized heat flux to the Te gradient, [EQUATION: SEE TEXT], is positive, while it becomes negative during the transition phase. The time for the transition increases as the normalized Te gradient is increased and exceeds the transport time scale characterized by the global energy confinement time. 相似文献
107.
Harris RK Becker ED Cabral De Menezes SM Granger P Hoffman RE Zilm KW;International Union of Pure Applied Chemistry Physical Biophysical Chemistry Division 《Solid state nuclear magnetic resonance》2008,33(3):41-56
IUPAC has published a number of recommendations regarding the reporting of nuclear magnetic resonance (NMR) data, especially chemical shifts. The most recent publication [Pure Appl. Chem. 73, 1795 (2001)] recommended that tetramethylsilane (TMS) serve as a universal reference for reporting the shifts of all nuclides, but it deferred recommendations for several aspects of this subject. This document first examines the extent to which the 1H shielding in TMS itself is subject to change by variation in temperature, concentration, and solvent. On the basis of recently published results, it has been established that the shielding of TMS in solution [along with that of sodium-3-(trimethylsilyl)propanesulfonate, DSS, often used as a reference for aqueous solutions] varies only slightly with temperature but is subject to solvent perturbations of a few tenths of a part per million (ppm). Recommendations are given for reporting chemical shifts under most routine experimental conditions and for quantifying effects of temperature and solvent variation, including the use of magnetic susceptibility corrections and of magic-angle spinning (MAS).
This document provides the first IUPAC recommendations for referencing and reporting chemical shifts in solids, based on high-resolution MAS studies. Procedures are given for relating 13C NMR chemical shifts in solids to the scales used for high-resolution studies in the liquid phase. The notation and terminology used for describing chemical shift and shielding tensors in solids are reviewed in some detail, and recommendations are given for best practice. 相似文献
108.
109.
110.
University of Georgia VIGRE Algebra Group 《Journal of Algebra》2004,280(2):371
Let G be a simple algebraic group over k=C, or where p is good. Set g=LieG. Given rN and a faithful (restricted) representation , one can define a variety of nilpotent elements . In this paper we determine this variety when ρ is an irreducible representation of minimal dimension or the adjoint representation. 相似文献