Multiple positive solutions for discrete nonlocal boundary value problems

In this paper, we investigate a second-order nonlinear difference equation with sign-changing nonlinearity subject to two different sets of nonlocal boundary conditions. The explicit expressions of the associated Green's functions are presented. By using a recently developed fixed point theorem, we establish sufficient conditions for the existence of multiple positive solutions of the boundary value problem.     

平行四边形的3-剖分

It has been proved that if a rectangle is dissected into three congruent pieces,then those pieces must themselves be rectangles. In the present paper this result is generalized to the case of parallelogram.     

降血糖新药格列美脲的HPLC含量测定法

采用ZORBAX—C18色谱柱(4.6 mm×150 mm,5μm),以甲醇-0.03 mol/L磷酸二氢胺水溶液(70:30,用磷酸调节缓冲盐水溶液的pH为3.5)作为流动相,流速1.0 mL/min;紫外检测波长为230 nm.用安定做为内标测定格列美脲(glimepiride,GMD)原药的含量.此方法对格列美脲的线性范围是10μg/mL～200 μg/mL,相关系数r>0.999 9;最低检测限为1.2 ng;平均回收率为99.39％～100.34％.RSD是0.33％～0.37％.结果表明用反相HPLC测定格列美脲原药含量操作简便,结果准确.     

Characteristics of Quantum Radiation as Tunneling from a Cylindrically Symmetric Black Hole

Applying the semi-classical quantum tunneling model, we have studied the Hawking radiation via tunneling from a cylindrically symmetric black hole. The derived results show that the tunneling rate of at the event horizon of the black hole is related to Bekenstein–Hawking entropy and the factual radiation spectrum is not strictly pure thermal, but is consistent with the underlying unitary theory. PACS numbers: 04.20.-s, 97.60.Lf.     

二维平板光子晶体直波导的制备和光传输特性的测量

利用聚焦离子束刻蚀的方法在SOI(silicon on insulator)基片上制备了W3型二维光子晶体直波导.观察并测量了近红外激光通过光子晶体波导的散射图形和透过谱.实验结果说明，激光在有引入引出脊形波导的光子晶体直波导中具有很好的传输特性. 关键词： 光子晶体波导 光子带隙 脊型波导     

Photonic band structures of two-dimensional photonic crystals with deformed lattices

Using the plane-wave expansion method, we have calculated and analysed the changes of photonic band structures arising from two kinds of deformed lattices, including the stretching and shrinking of lattices. The square lattice with square air holes and the triangular lattice with circular air holes are both studied. Calculated results show that the change of lattice size in some special ranges can enlarge the band gap, which depends strongly on the filling factor of air holes in photonic crystals; and besides, the asymmetric band edges will appear with the broken symmetry of lattices.     

一个关于球面和环面上嵌入图的近-三角剖分嵌入的内插定理(I)

一个近-三角剖分嵌入是指一个曲面上的嵌入图使得几乎所有的面都是三角形,至多只有一个可能的例外.文中作者证明了如下结论:如果一个图G 在球面S₀(或环面S₁)上有近-三角剖分嵌入,那么G在每一个可定向曲面S_k有近-三角剖分嵌入,其中k=h,h+1,\cdots ,\lfloor\frac{\beta(G)}{2}\rfloor$, 而h=0(或1)并且β(G)是图G的Betti数.特别地,G是上可嵌入的.     

On the local and asymptotic behavior of Brownian motion on simply connected nilpotent Lie groups

The aim of this paper is to study the local and asymptotic behavior of Brownian motion on simply connected nilpotent Lie groups. We carry over a qualitative version of the Erdös-Rényi law of large numbers for Brownian motion to simply connected step 2-nilpotent Lie groups. The method applied gives rise to a proof for qualitative results concerning the modulus of continuity of Brownian motion on simply connected step 3-resp. step 2-nilpotent Lie groups without using the Ventsel-Freidlin theory as in Baldi.     

PT-PEK-c电光聚合物薄膜的厚度和介电性质

研制了新的PT-PEK-c电光聚合物薄膜材料,用准波导耦合m线方法测量了PT-PEK-c电光聚合物薄膜的厚度,并测量了该聚合物薄膜在1×10²Hz到1×10⁷Hz频率范围内的室温介电常数.测量结果为:厚度d=2.328±0.315μm,在10KHz下,介电常数ε_r＝4023±0.063,介电损耗tanδ＝0.003.     

多模玻色二次多项式型系统的特性函数和准概率分布函数

运用多模玻色系统广义线性量子变换的普遍理论，对多模玻色二次多项式型系统进行了研究.给出了多模玻色二次多项式型系统的正规、反正规、Wigner特性函数、P表示和Q表示.举例讨论了该系统的压缩性质. 关键词： 多模玻色二次多项式型系统 特性函数 准概率分布函数