Superconductivity in Bilayer Cuprates

We calculate the stability of d_x²-y² wave superconducting state in bilayer cuprates within the antiferromagnetic and van Hove scenario. We find an increment ~10 K of T_c^max with the growth from one plane to a bilayer when the hole pairing induced by the spin-wave exchange is included.     

离子液体1-丙基-3-甲基咪唑醋酸盐[C_3mim][OAc]蒸气压和蒸发焓的测定及极性预测

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In this paper, we first study the strong law of large numbers for the frequencies of occurrence of random ordered couples of states for nonhomogeneous bifurcating Markov chains indexed by a binary tree. Then the strong law of large numbers are studied for functions of the nonhomogeneous bifurcating Markov chains indexed by a binary tree. As a corollary, we obtain the shannon-McMillan theorem for these Markov chains with finite state space.     

The fluidity and molding ability of glass-forming Zr-based alloy melt

The fluidity and filling ability of glass-forming Zr-based alloy melt in copper mould were investigated both theoretically and experimentally. The major factors which affected the flowing behavior of the metallic melt in the mold were determined, which provides the foundation for overcoming the contradiction between the filling and formation of amorphous alloy during the rapid cooling process of the metallic melts. The casting factors to prepare a metallic ring were discussed and selected. As a result, a Zr-based bulk metallic glass ring was prepared successfully. Supported by the National Natural Science Foundation of China (Grant No. 50731005), SKPBRC (Grant No. 2006CB605201/2007CB616915), PCSIRT (Grant No. IRT0650), the Natural Science Foundation of Hebei Province of China (Grant No. E2004000209), the Scientific Research Foundation of Education Department of Hebei Province of China (Grant No. 2004464), and the Experts and Scholars Fund of Personnel Department of Hebei Province, China (Grant No. 2003)     

溶液临界现象研究进展

溶液临界现象是热力学研究中的一个重要领域,其对于认识临界普适性规律以及理解和应用由于超常临界涨落引起的溶液特殊性质具有重要意义.本文简述了临界现象的基本概念和研究历史,介绍了近年来溶液临界现象的研究进展,重点评述了以下几个方面的理论和实验成果:(1)临界指数与指前因子标度关系在溶液体系中的普适性;(2)完全标度理论的建立、发展及其实验检验;(3)临界区域与非临界区域的跨接现象;(4)多元溶液中的三临界现象;(5)临界溶液中的化学反应速率及平衡常数的奇异性.     

北京谱仪Ⅱ顶点探测器的离线刻度

介绍了在VCJULI基础上对北京谱仪Ⅱ顶点探测器进行离线刻度的方法,包括整体T0的获得、单丝零时间t0的扣除、丝位的修正、顶点探测器相对于主漂移室位置的校正以及漂移时间一漂移距离关系的修正等.并由此给出了北京谱仪Ⅱ顶点探测器的主要参数:空间分辨好于100μm.     

RFQ加速器同时加速同荷质比正负离子的实验研究

阐述了利用北京大学26MHz 300keV整体分离环高频四极场(ISR RFQ)加速器同时加速同荷质比正负离子的研究结果.分别用O⁺和O^－离子的连续束以及脉冲束同时注入,均实现了RFQ加速器对同荷质比正负离子的同时加速.用快靶测得的经RFQ腔同时加速后形成的O⁺及O^－离子微脉冲束与预想的正负氧离子微脉冲束相位关系完全一致.证实了同时加速时得到的氧离子束总和明显高于单加速一种离子时得到的氧离子束.在国际上首次实现了用RFQ加速器同时加速同荷质比的正负离子.