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861.
Hua Ning LIU Wen Peng ZHANG 《数学学报(英文版)》2007,23(5):915-924
The main purpose of this paper is to use the generalized Bernoulli numbers, Gauss sums and the mean value theorems of Dirichlet L-functions between a quadratic residue and its inverse modulo p value formula. to study the asymptotic property of the difference (a prime), and to give an interesting hybrid mean 相似文献
862.
863.
针对90t RH精炼装置,以水力学模拟研究了吹气孔直径对真空循环精炼过程中钢液流动和混合特性的影响.模型和原型的相似比为15.模型吹气孔直径分别为0.8 mm和1.2 mm.结果表明,1.2 mm孔径下环流量和主要工艺参数间的关系为Ql Q80.26Du0.69Dd0.80;在给定的吹气量和插入管内径下,增大吹气孔直径并不显著改变精炼过程中钢液流动特征,环流量随吹气孔直径的增大而略有增大,其关系式为Ql=2.40Q 0.23gD0.72u D0.88d d0.13in;相应地,混合时间稍有缩短;0.8和1.2 mm孔径下,τm与搅拌能密度的关系分别为τm ε5和τm ε0.49. 相似文献
864.
D. Seweryniak P. J. Woods B. Blank M. P. Carpenter T. Davinson S. J. Freeman J. Grres A. Heinz R. V. F. Janssens H. Mahmud T. L. Khoo Z. Liu G. Mukherjee E. Rehm F. Sarazin J. Shergur M. Shawcross S. Sinha A. Woehr 《Physics letters. [Part B]》2004,590(3-4):170-175
The fusion–evaporation reaction 10B(12C, 2n) was used to make the first observation of in-beam γ decays from the astrophysically important nucleus 20Na, lying adjacent to the proton drip-line. All states below the proton threshold in 20Na were populated and identified in the experiment. These include new levels, previously unresolved levels, and states located with improved energy precision. The level structure of 20Na, and its γ transitions, are compared to the mirror partner 20F measured simultaneously in this experiment. In particular, a high degree of energy stability is found for all negative parity states. These results are discussed in the context of the nuclear shell model. 相似文献
865.
提出级联佛克脱型原子滤光器(Linked VADOF)的新构想。从理论上分析并计算了级联佛克脱型原子滤光器的透射谱。结果表明,级联佛克脱型原子滤光器将佛克脱型原子滤光器的多峰改造为单峰结构,具有比佛克脱型原子滤光器更窄的线宽和更高的噪声抑制比。将这种新型结构应用于激光信标锁频。该锁频方案提高了信标光频率的稳定性。在此基础上,给出了发射端采用级联佛克脱型原子滤光器锁频,接收端采用法拉第型原子滤光器(FADOF)滤光的新型卫星激光链路系统。外场初步联调实验表明了该系统的可行性。 相似文献
866.
本文描述了利用KTP晶体和腔的基波输出镜构成非线性镜实现1.08μmNd:YAP激光器的被动锁模。实验表明,这种新的锁模技术比用染料作可饱和吸收体的被动锁模技术有很多突出的优点,具有很大的发展潜力。实验测得锁模时基波1.08μm输出2.4mJ,二次谐波0.54μm输出0.5mJ(同样条件下的静态输出为2.5mJ),基波脉冲的平均脉宽为40ps。 相似文献
867.
X-ray absorption spectra of plasmas 总被引:1,自引:0,他引:1
In this paper we present a theoretical method to calculate the absorption spectra of hot dense plasmas. Based on our fully relativistic treatment incorporated with the quantum defect theory to handle the huge number of transition arrays from many configurations with high principal quantum number, we can calculate the absorption spectra for any element or multi-element plasmas with little computational efforts. We calculate the absorption spectra of C10H1605 plasmas, which are in good agreement with the experimental spectra. We can then provide diagnostic analysis for plasmas in relevant inertial confinement fusion (lCF) experiments; namely not only to determine plasmas' temperatures and densities, but also to provide the population densities of various ionic stages. Our theoretical method verified by "benchmark experiments" will be a basic tool to provide "precise" opacity data for the ICF research.`` 相似文献
868.
A regular simple geodesic loop on a tetrahedron is a simple geodesic loop which does not pass through any vertex of the tetrahedron. It is evident that such loops meet each face of the tetrahedron. Among these loops, the minimal loops are those which meet each face exactly once. Necessary and sufficient conditions for the existence of minimal loops are obtained. These conditions fall naturally into two categories, conditions in the first category being called coherence conditions and conditions in the second category being called separation conditions. It is shown that for the existence of three distinct minimal loops through any point on the face of a tetrahedron it is necessary and sufficient that the tetrahedron be isosceles, which, in turn, amounts to the tetrahedron satisfying three coherence conditions. All other regular simple geodesic loops on an isosceles tetrahedron are then classified. Finally, coherence conditions for the existence of similar loops on an arbitrary tetrahedron are found. 相似文献
869.
Meng F. Q. Lu M. K. Yang Z. H. Zeng H. 《Journal of Thermal Analysis and Calorimetry》1998,52(2):609-613
The thermal behavior of two new non-linear optical (NLO) materials, urea-(D) tartaric acid (UDT) and urea-(DL) tartaric acid
(UDLT) were studied by using DSC, TG and TMA. The results show that: 1) The two crystals have different melting points but
similar decomposition temperatures due to the influences of intermolecular forces, which is attributed to the stereo effects
of (D)-tartaric and (DL)-tartaric acid molecules; 2) There was only thermal expansion and no thermal contraction when the
UDT and UDLT crystals were heated; 3) There was no phase transition within the measured temperature range; 4) The thermal
expansion of the UDT and UDLT crystals shows a small anisotropy; 5) The specific heats of UDT and UDLT change linearly with
temperature in the measured temperature range and the value for UDT is 1.321 J g-1 K-1 at 320 K while the specific heat of
UDLT is 1.357 J g-1 K-1 at the same temperature.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
870.