Differential operators and immersions of a Riemann surface into a Grassmannian

We consider equivariant holomorphic immersions of a universal cover of a compact Riemann surface X into a Grassmannian satisfying a nondegeneracy condition. The equivariance condition says that there is a homomorphism ρ of the Galois group to that takes the natural action of the Galois group on to the action of the Galois group on defined using ρ. We prove that the space of such embeddings are in bijective correspondence with the space of all holomorphic differential operators of order two on a rank n vector bundle over X with the property that the symbol of the operator is an isomorphism.     

基于丙烯酸-丙烯酰胺共聚物的氧化铟锡蚀刻油墨的制备与性能

以丙烯酸（AA）、丙烯酰胺（AM）为单体,采用水溶液聚合法制备了低黏度聚（丙烯酸-丙烯酰胺）P（AA—Co—AM）树脂。使用旋转黏度计和热重分析仪等测试了树脂的性质,并以该树脂为连接料,制备了新型水性氧化铟锡（ITO）蚀刻油墨。探讨了该油墨的保水性、pH变化和蚀刻图像解析度等。结果表明：通过优化合成工艺可制备分子量适宜的P（AA—CO—AM）树脂,它在150℃以下无分解现象;油墨在使用3h后失水率仅为3．68％-5．34％,存放60d后pH基本无变化,且丝网印刷效果明显好于市售油墨。     

具有积分边界条件的二阶半线性奇摄动方程脉冲状对照结构(英文)

本文讨论了带有积分边界条件的二阶半线性奇摄动方程的脉冲状对照结构.借助于边界函数法,在一定条件下,构造了该问题的形式渐近解.利用缝接法证明了该问题解的存在性和形式渐近解的一致有效性.     

Lax Connection of Strings in γ-Deformed Backgrounds

In this paper we consider classical strings propagating in γ-deformed AdS3 × S^3 backgrounds generated by TsT transformation on the AdS3 sector, which is described as the group manifold SL（2, R）, then we prove that the U（1） currents of strings with the twisted boundary conditions are equal to those in γ-deformed backgrounds. Using TsT transformation, we can derive the local Lax connection and the monodromy matrix in γ-deformed backgrounds with the spectral parameter, which ensures the classical integrability of the string theories.     

Epidemic Spread in Networks Induced by Deactivation Mechanism

We have studied the topology and epidemic spreading behaviors on the networks in which deactivation mechanism and long-rang connection are coexisted. By means of numerical simulation, we find that the clustering coefficient C and the Pearson correlation coefficient r decrease with increasing long-range connection μ and the topological state of the network changes into that of BA model at the end （when μ = 1）. For the Susceptible-Infect-Susceptible model of epidemics, the epidemic threshold can reach maximum value at μ = 0.4 and presents two different variable states around μ= 0.4.     

部分剪力连接钢—砼组合梁的滑移及曲率分析

对受均布荷载作用的简支部分剪力连接钢－砼组合梁的滑移应变和滑移的分布规律进行了理论分析,得出部分剪力连接钢－砼组合梁的剪力连接程度系数与滑移应变和滑移的关系。分析了考虑滑移效应的梁的曲率及其与剪力连接程度系数之间的关系。结果与结构在弹性阶段的实验相当吻合,对组合梁挠度的精确计算有指导意义。     

焊管的残余应力测试与研究

通过小孔法与分割法对φ272mm螺旋埋弧焊管和φ380mm对接焊管的残余应力测试,分析探讨了螺旋焊缝、环焊缝以及焊缝热影响区的残余应力分布。研究结果表明,不同工艺焊接成型的圆管,其焊缝纵向均匀为拉应力分布,焊缝横向均为压应力分布,焊缝热影响区的残余应力分布各异。     

利用变压器研究两个互感线圈的串并联

利用变压器研究了两个互感线圈串并联的等效电感。     

电磁热效应裂纹止裂的实验研究

通过本文给出的实验表明：利用电磁场的热效应对载流导体中的裂纹进行止裂是一种行之有效的方法。在电磁场作用瞬间,由于裂尖处的热集中效应,能够使其在附近一定范围内熔化形成微小焊口。由此,裂纹前缘处的曲率半径增加了2-3个数量级。同时,细化了裂纹前缘的显微组织,提高了材料的韧性,显著地减少了应力集中,阻止了干线裂纹源的形成,可有效地遏制了裂纹的扩展。文中介绍了实验原理、方法和结果;讨论了一些参数之间的关系。