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991.
A method based on circuit model is used to tune the first home-made 9-cell TESLA type superconducting niobium cavity at Peking University.After tuning,a flat field profile with a final π-mode frequency within 3 kHz of target frequency is achieved.The field flatness is measured by a bead-pull method,and the relative electric field is calculated from the frequency shift perturbed by the bead stepping along the axis of the cavity. 相似文献
992.
There is a 1941 conjecture of Erdos and Turán on what is now called additive basis that we restate:
Suppose that
If 0$"> for all , then is unbounded.
Conjecture 0.1(Erdos and Turán). Suppose that is an increasing sequence of integers and
Suppose that
If 0$"> for all , then is unbounded.
Our main purpose is to show that the sequence cannot be bounded by . There is a surprisingly simple, though computationally very intensive, algorithm that establishes this.
993.
Joachim Zacharias 《Proceedings of the American Mathematical Society》2006,134(7):1909-1916
Recently J.Roe considered the question of whether for a discrete group the reduced group -algebra is the fixed point algebra of Ad acting on the uniform Roe algebra . is said to have the invariant translation approximation property in this case. We consider a slight generalization of this property which, for exact , is equivalent to the operator space approximation property of . We also give a new characterization of exactness and a short proof of the equivalence of exactness of and exactness of for discrete groups.
994.
Using the new two-dimensional cranking relativistic mean field (RMF) approach, the shears mechanism of magnetic rotation based on configuration πh211/2⊙νh-211/2 in 142Gd is microscopically and self-consistently examined by investigating the aligning angular momenta of the valence nucleons. 相似文献
995.
The accelerators should be properly designed to make the radiation field produced by beam loss satisfy the dose limits. The radiation field for high intensity H- cyclotron includes prompt radiation and residual radiation field. The induced radioactivity in accelerator components is the dominant source of occupational radiation exposure if the accelerator is well shielded. The source of radiation is the beam loss when cyclotron is operating. In this paper, the radiation field for CYCIAE-100 is calculated using Monte Carlo method and the radioactive contamination near stripping foil is studied. A method to reduce the dose equivalent rate of maintenance staff is also given. 相似文献
996.
设 $\Lambda$ 是域$k$上的有限维代数. 则 $\Lambda$的低阶 Hochschild上同调群在有限维代数的表示理论中扮演着重要的角色. 该文得到了 $l$ -遗传代数的一阶和二阶Hochschild 上同调群的维数方程. 相似文献
997.
本文研究了正定厄米特矩阵Schur补的迹和特征值的性质,通过一个不等式的证明,得到了正定厄米特矩阵和的Schur补与正定厄米特矩阵Schur补的和的迹和特征值之间的不等式. 相似文献
998.
Abdulmuhsen H. Ali 《International Journal of Theoretical Physics》2009,48(1):194-212
The derivation of the statistical nature of the quantum mechanical wave function is presented within the formalism of quantum
mechanics and the second quantization. The statistical wave function may be derived for non relativistic bosons, non relativistic
fermions, and relativistic bosons by employing the commuting field operator
. For relativistic electrons a strictly anticommuting
must be employed to derive the statistical wave function (spinor). The discussion at the end of the paper aims to show the
physical plausibility of a statistical wave function. 相似文献
999.
刘玉 《纯粹数学与应用数学》2007,23(2):255-261
刻画了2×2全矩阵代数保立方幂等映射,利用保立方幂等映射象与原象矩阵对应元素相等这个特点计算出相应的结果,得出特征不等于2,3,5域上2×2全矩阵代数保立方幂等单射的一个具体的刻画. 相似文献
1000.
给出了左C-半群的另一种结构,所谓左交错积结构,并刻画了它的特殊情形.这种结构为左C-半群在广义正则半群类中的再推广奠定了基础. 相似文献