高压处理对BiSrCaCu2Oy超导电性的影响

 本文在高T_c超导体BiSrCaCu₂O_y常压制备的基础上，研究了热压烧结和冷压处理对其形成、结构及超导电性的影响，并与常压结果进行了比较。结果表明，高压可以使样品的合成时间缩短，合成温度降低。但同时它也抑制了晶格参数较大的相（高T_c相）的形成，使小晶格参数的杂相含量增多。对于提高样品的超导电性而言，1.5 GPa时一个较好的压力点。     

Correlation of Moments and Critical Phenomenon in Disassembly of Hot Nuclei

We used Monte Carlo method to generate the configurations of disassembly of hot nucleus Au* based on the Atomic Mass Table and the conservation of mass and charge number.The resulted charge distribution of fragments was then used to calculate the conditional moments.The logarithm correlation between second and third moments of experimental charge distribution is very well reproduced by theory.It seems that no connection to the critical phenomenon of concerned system exists.     

The Decay of 120Ba

¹²⁰Ba was produced by 68MeV ¹⁶O beam bombarding a 2mg/cm² thick ¹⁰⁶Cd target and fluorated in a halium-jet ion source.The decay of on-line mass separated activity ¹²⁰Ba has been studied by γ-X,γ-γ γ-β coincidence measurements.Its halflife was measured to be 24±2s.The total decay energy was extracted to be Q_EC=5.0±0.3MeV.A simple decay scheme has been proposed.     

Boson Representations of Subalgebra Chain for Quantum Algebra (Cl)q with q a Root of Unity

The method of q-deformed boson realization is extended to the caee that q is a root of unity. By using thb method, many irreducible and indecomposable representations of each su balgebra in a su balgebra chain of the quantum universal enveloping algebra (quan tum algebra) (C_l)_q are obtained on the q-deformed Fock space and its quotient space. AB an example, the representations of (C₃)_q are constructed in explicit forms. Besides, by embedding (A₁)_q = (C_l)_q, into the subalgebra chain, a new realisation of (A₁)_q and its representations are obtained.     

准一维有机铁磁体的磁性机理研究

对准一维有机铁磁体ｐｏｌｙ－ＢＩＰＯ体系的磁性机理进行了研究。详细考虑了该体系中的电子跳跃、电子关联及派尔斯不稳定性，自洽地计算了其能带结构和自旋密度分布，并数值地研究了各因素对系统特性的影响。结果发现该体系基态为稳定的铁磁态． 关键词：     

重水的冲击压缩性

 用二级轻气炮作为加载装置，测量了重水（D₂O）的冲击压缩线，压力范围为10~43 GPa。用轴对称式电磁感应探头测量冲击波速度，测量精度约1.2%~1.5%。用电探针测量飞片速度，其精度约0.5%。用对比法原理进行测量，标准样品材料为无氧铜。实验发现，重水的冲击波速度随粒子速度变化呈斜率不同的两段直线关系，两线连结处出现拐折。分析认为，这一现象可能由液体D₂O分子在冲击波作用下的离解过程引起。     

The WKBZ mode approach to sound propagation in range-independent ocean channels

I.IntroductionThenorma1-modeapproachcangiveanexactso1utiontotheacousticfie1dinastratifiedmedium,soitisoftenusedtocomparewithotherapproximatemethodssuchasraytheory,parabo1icequationl'](PE)methodandGaussianbeam[21approach,andtakenasacriteriontochecktheaccuracyofapproximatemeth0dsl3J.Themodeapproachmayalsobeextendedtorange-dcpendente..i,onmentsl4.5l.Thoughtherearemanynumerica1propagationcodesbasedonthemodeapproachI'],theconventionalmodeapproachisawkwardtoapplyt0'higherfrequencya-ndbroadbandprop…     

同步扫描－固体基质室温磷光法同时测定痕量对位三联苯和间位三联苯的研究

本文提出了一种新的测定间三联苯和对三联苯的同步扫描－ＳＳ－ＲＴＰ法。固体基质选用慢速定量滤纸，重原子盐为Ｔｌ２ＳＯ４。以激发单色器和发射单色器的波长差△λ＝１８０ｎｍ进行同步扫描，其同步特征峰间三联苯为４５０ｎｍ，对三联苯为４９０ｎｍ（均指发射波长）。间三联苯可直接由该特征峰的高度进行定量测定。对三联苯在４９０ｎｍ处的特征峰略受间三联苯同步拖尾的影响，其峰值信号需加校正。间三联苯和对三联苯的线性范围分别为０．４６～９２ｎｇ／斑点和０．４６～４６ｎｇ／斑点     

美式期权定价中非局部问题的有限元方法

在本文中 ,我们关心的是美式期权的有限元方法 .首先 ,根据 [4 ]我们对所讨论的问题引进一个新奇的实用的方法 ,它涉及到对原问题重新形成准确的数学公式 ,使得数值解的计算可以在非常小的区域上进行 ,从而该算法计算速度快精度高 .进而 ,我们利用超逼近分析技术得到了有限元解关于 L2 -模的最优估计 .     

强奇异卷积算子交换子的Hardy型空间估计

本文给出了强奇异卷积算子交换子[6,T]在Hardy型空间中的估计,其中 b∈BMO(Rn)且一致连续, T为强奇异卷积算子.