税企博弈模型──防止出口骗税的一个对策

本文初步探讨了现行出口骗税行为处罚所产生的负效应，进而建立了税企博弈模型．在国家税收期望损失为零的情况下，首次提出了出口骗税罚款系数公式（L）．该公式揭示了罚款系数与检查概率之间的关系，为税务决策部门制定罚款系数及税务操作部门安排检查力量提供了理论依据．公式（L）可操作性强，具有一定的实用价值．     

一类变系数线性波动方程初值问题的求解

本文讨论了一类变系数线性波动方程初值问题的求解，获得较为理想的结果．     

Diffusion of ethylene glycol accompanied by reactions in poly(ethylene terephthalate) melts

Diffusion coefficients of ethylene glycol (EG) have been measured in poly(ethylene terephthlate) (PET) melts by a quartz-spring sorption apparatus. A simple mathematical model was developed to investigate the sorption behavior accompanied by chemical reactions of EG and PET at high temperatures. Diffusion coefficients are deduced from experimental data for an asymptotically thin sample in order to minimize the effects of reactions. The diffusion coefficient of EG is strongly dependent on the vapor pressure of EG and temperature but not on the molecular weight of PET in this experimental range (degree of polymerization 80–120). The diffusion coefficient of EG in PET melt at 265°C is 2.58 × 10^?7 cm²/s at the limit of zero concentration of EG. The activation energy for diffusion is 38.4 kcal/gmol, and the heat of solution for sorption is ?44.9 kcal/gmol. The concentrations of the volatile materials resulting from reactions in PET-EG system were analyzed with gas chromatography. In addition, a fit of the current model to experimental data yields frequency factors for the polymerization reaction (k₁) and the acetaldehyde formation reaction (k₂) to be 5.84 × 10⁸ cm³/mol ? min and 3.90 × 10¹¹ min^?1, respectively.     

声学实验及部分声学量的测量

根据超声波在损耗介质中的淮驻波效应，对声速测量实验的内容进行了重新设计，丰富了机械波实验的内容和实验数据处理手段。     

The Inverse Spectral Problem for the Sturm-Liouville Operators with Discontinuous Coefficients

We study the inverse spectral problem for the Sturm–Liouville operator whose piecewise constant coefficient A(x) has discontinuity points x _k , k=1,...,n, and jumps A _k =A(x _k +0)/A(x _k -0). We show that if the discontinuity points x ₁,...,x _n are noncommensurable, i.e., none of their linear combinations with integer coefficients vanishes; then the spectral function of the operator determines all discontinuity points x _k and jumps A _k uniquely. We give an algorithm for finding x _k and A _k in finitely many steps.     

Non-linear waves in a fluid-filled inhomogeneous elastic tube with variable radius

In the present work, by employing the non-linear equations of motion of an incompressible, inhomogeneous, isotropic and prestressed thin elastic tube with variable radius and the approximate equations of an inviscid fluid, which is assumed to be a model for blood, we studied the propagation of non-linear waves in such a medium, in the longwave approximation. Utilizing the reductive perturbation method we obtained the variable coefficient Korteweg–de Vries (KdV) equation as the evolution equation. By seeking a progressive wave type of solution to this evolution equation, we observed that the wave speed decreases for increasing radius and shear modulus, while it increases for decreasing inner radius and the shear modulus.     

非水溶液盐效应的气液色谱研究——非电解质(烃、芳烃、氯代烃、酮)+盐(NaI、NaSCN、KSCN)+碳酸丙烯酯体系

由于碳酸丙烯酯(PC)具有较宽的液相区间(mp:224.0K,bp:514.9K)、较高的介电常数(64.92,298.15K)和较大的偶极矩(4.94D),它是一个在工业和科学研究中有广泛应用的非质子型极性溶剂。已有大量文献就PC溶液中电解质-PC、非电解质-PC和离子-离子间的相互作用情况作了报导。对于非电解质-电解质-PC三元系中溶质-溶剂间的相互作用情况还缺乏了解。本文希望通过测定非电解质溶质在PC的电解质溶液中的无限稀释活度系数γ_1~∞,对非水溶液中的溶质-溶剂作用情况有新的了解。气液色谱法(CLC)是测定无限稀释溶液活度系数的有效方法之一。作者曾利用GLC测定了一些烃、氯代烃、醇、酮在环丁砜电解质溶液中的无限稀释活度系数和盐效应常数.     

新疆××金矿主要矿物的标型特征及其意义

摘要黄铁矿的反射率均低于标准黄铁矿。含金黄铁矿的晶胞参数a_0为5.4170A—5.4175A、热电系数为正值。在600—200(cm~(-1))波数内,红外光谱曲线的吸收谷较为开阔,且随含金量的增加有向长波方向产生系统位移的趋势。在其求I矿,氧、氢和碳的同位素丰度是:δO_(SiO_2)~(18)11.93—16.3‰、δO_(H_2)~(12)O-1.06—4.34‰、δD—84.4—-128.8‰、δC~(13)-12.92—-17.22‰。在石英的包裹体气相中,CH_4/CO_2值为0.009—0.056,在液相中,l_7矿脉富K~+,l_(17)矿脉的K~+、Na~+相等,其它均为富Na~+型。离子组合及矿化度与岩体一致,矿化度属淡水型。文中还提出了说明矿床成因的地质年龄、化探成果、稳定同位素和流体包裹体成分的依据,补充了找矿评价的硫化物存在、黄铁矿的热电系数和红外谱标志。     

Effect of AlN content on the performance of brominated epoxy resin for printed circuit board substrate

Polymer matrix composites, based on brominated epoxy, a type of material widely used in printed circuit boards (PCBs), as matrix and AlN particle as filler were prepared. The influences of AlN content on the mechanical, thermal, and electrical properties of the composites were investigated by uniaxial tensile test, TMA, thermal conductivity measurement, DMA, and dielectric properties measurement. It was found that the properties of composites monotonically varied with AlN content except that maximum tensile strength and strain of composites corresponded to a filler content of 10 wt %. The results of DMA also showed the AlN reinforcement was more pronounced above T_g, and the peak area of tan δ versus T curves decreased with AlN content, which implied the damping capacity of the composite gradually decreased. The increase in T_g and decrease in damping were probably due to strong interaction between the AlN and epoxy matrix inhibiting the mobility of the epoxy chain. In addition, different theoretical models reported in the literature were used to predict the E, CTE, k, and D_k, and compared with the experimental data. Finally, suitable models were recommended in the present materials system. For the significant improvement of performance of epoxy, we can conclude that these composite materials may be promising for PCB substrate. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1662–1674, 2007     

Diffusion approximation for billiards with totally accommodating scatterers

We study the 2D motion of independent point particles colliding with a periodic array of circular obstacles. The interaction between the particles and the obstacles is described by a total accommodation reflection law. Assuming that the array of scatterers has finite horizon, the density of particles is approximated by the solution of a diffusion equation in the long-time and large-scale regime. The proof relies on a multiscale asymptotics and gives the order of approximation.