共查询到20条相似文献,搜索用时 93 毫秒
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We present the preliminary results on the spin alignment matrix
element ρ00 for vector mesons K*0(892) and
φ(1020) in mid-central (20%—60%) Au+Au and p+p collisions at sNN=200GeV. The values of ρ00 with respect to reaction plane in Au+Au collisions are 0.36±0.02(stat)±0.13(sys) for K*0(892) and 0.38±0.01 (stat)±0.04 (sys) for φ(1020). No evident global spin alignment with respect to reaction plane is observed in the measured pT region up to 5GeV/c with current sensitivity. ρ00 with respect to the production plane of the vector meson is also measured for K*0(892) and φ(1020) in Au+Au collisions, and for φ(1020) in p+p collisions. No significant difference for the ρ00 between Au+Au and p+p collisions is observed with our data sample. 相似文献
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原子核电荷半径Rc所有的实验数据都表明, Rc系统偏离A1/3律, 即随A增大Rc/A1/3系统地递减, 而Rc/Z1/3则比较接近于一个常量. 原子核巨单极共振能量Ex ∝ R-1的大量实验数据也支持这一结论. 根本原因在于A1/3律与同位旋无关, 而Z1/3律已部分反映了同位旋的影响. 基于壳模型, 给出了Z1/3律的微观诠释. 壳模型中质子和中子谐振子势强度参数ωp和ωn的差异, 可以用Z1/3律说明. 基于与Wigner的原子核同位旋多重态质量公式(IMME)相似的理论考虑, 提出了核电荷半径改进的Z1/3律. 相似文献
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Abstract Fourier transform infrared spectroscopy has been used to study quantitatively the acetylation of monodisperse polystyrene microspheres with diameters ranging from 7 to 9μm. The CH2 stretching infrared vibration mode at 2921 cm?1 was used as the internal intensity standard. The acetylation extent could be easily measured by comparing the relative intensities of the bands of acetyl group (1678, 1415, 1359 cm?1) or the bands due to the para-substituted benzene ring to the band at 2921 cm?1 from the calibration curve. 相似文献
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T. M. Ivanova O. L. Lependina V. A. Smrchek I. N. Sinitsyna 《Journal of Applied Spectroscopy》1995,62(1):126-129
To whom correspondence should be addressd. 相似文献
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在采用体积相加原理计算混合物物态方程的基础上,建立了一种物理模型确定混合物温度。根据混合物中各组分温度和压强平衡条件,采用压强-密度迭代方法计算给出混合物物态方程,编制了两种组分的混合物物态方程计算程序。为检验建立的温度模型的合理性及程序的有效性,分析了不同密度、温度状态的氢(H2)和钨(W)组成的混合物状态参量,计算了以下情形及其组合情形的混合物物态方程:H2和W以不同质量比混合;质量比固定,单组分状态不同;温度区间和密度区间不同。研究表明:实际应用中在建立的混合物温度模型基础上确定的混合物物态方程是合理的。 相似文献
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傅里叶望远镜外场实验性能改进和结果分析 总被引:4,自引:0,他引:4
为了实现对傅里叶望远镜成像系统更接近实际的仿真,改进了外场实验系统结构。采用反射式目标,利用准直扩束镜替代空间滤波器和准直透镜,使用大靶面电荷耦合器件作为监视器。在无大气和包含200m水平大气两种情况下,分别对2.5mm的4种不同空间频谱分布目标进行实验。实验选用9×9,17×17,33×33和65×65傅里叶分量分别进行重构。最高成像角分辨率为3.5″。结果表明含大气与无大气重构结果的Strehl比值相近,从而证明傅里叶望远镜成像系统能够克服下行链路低阶大气扰动的影响。 相似文献
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T. S. Lebedev 《高压研究》2013,33(1-6):720-722
Abstract Results of petrophysical PT-experiments are discussed. Used is a method of program modeling of experiments. Thermobaric dependence of elastic properties of acid, intermediate and basic rocks as well as elastic wave velocity anisotropy in amphibolites is studied. Deep PT-regimes effect on electrical resistance of dry and water-saturated rocks has been studied. PT-conditions of full loss of the remanent magnetization of volcanites have been established. A number of regional petrophysical lithosphere models has been constructed. 相似文献
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Simulated contours of self-reversed lines of Tl at 535 nm (72S1/2−62P3/2) and 378 nm (72S1/2-62P1/2) in alternating-current closed-arc radiation in mercury vapor with an addition of Tll were compared with experimental contours.
It is shown that while a single self-reversed contour has many different sets of model parameters that ensure coincidence
of experimental and calculated profiles, in the case of operation with a large data file of contours that correspond to different
directions of observation along chords perpendicular to the discharge axis, and with different lines that have a common level,
such a set of parameters becomes virtually unique. Instantaneous spatial distributions of Hg and Tl atoms in the ground state
and of Tl atoms in the 62P3/2 state are determined and the parameters of the van der Waals broadening of the 72S1/2 level are found. It is shown that a considerable “red” shift of absorption contours in the outer layers of the discharge
is observed. The results obtained contradict the presumed existence of local thermodynamic equilibrium in the given discharge.
Reported at the Conference “Plasma Physics and Plasma Technologies,” Minsk, September 15–19, 1997
Petrozavodsk State University, 33, Lenin Ave, Petrozavodsk, 185640, Russia. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 65, No. 5, pp. 761–768, September–October, 1998. 相似文献
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A study of aggregation of sulphur particles in colloidal suspension of sulphur in water-methanol mixture using TEM and electron
diffraction is reported. From the micrographs the aggregates formed have been found to be random and tenuous indicating a
fractal structure. The electron diffraction patterns of the aggregates are used to study the mechanism of diffusion and reaction
limited aggregation. 相似文献
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Using time-resolved high-speed shadowgraphy, the dynamics of phenomena due to laser-based lithotripsy is studied. Collapsing mechanism of bubble formed therein is investigated. In order to study the mechanism, the optically implemented mathematical morphology is applied. The study of the shape of the plasma and the collapsing region of the bubble of fluid that we are studying can possibly be used for practical application for laser-based lithotripsy. 相似文献
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利用神经网络提高编码器精度的方法 总被引:1,自引:0,他引:1
介绍了编码器误差的构成及特点,针对系统误差的分布规律与特点提出了基于神经网络的误差修正方法。采用非线性逼近精度较高的径向基函数神经网络,以采样点的角度值作为网络的输人样本,以高精度检测编码器的检测值作为学习目标建立了误差修正模型。实验结果表明,采用此种方法可将编码器的精度提高至原来的3倍以上,可有效地改善编码器的系统精度。 相似文献