Sine-azimuthal wavefront-modulated cosh-Gaussian beams with half-space amplitude modulation

Half-space amplitude modulation was introduced into the linearly polarized cosh-Gaussian beams with sine-azimuthal variation wavefront, and corresponding tunable focal patterns were investigated in detail. Simulation results show that focal pattern can be changed remarkably by the amplitude modulation. And under condition of different beam parameters and phase parameter that indicates the sine-azimuthal variation wavefront, the focal pattern evolution also differs considerably. Some novel focal shape may appear, including cross-shape, multiple-peak focal pattern, multiple intensity lines, wheel focal pattern, bell shape, and swallowtail focal spots. Symmetry of the whole focal pattern can be altered remarkably, the whole focal pattern evolves into uniaxial symmetry about perpendicular axes for odd and even phase parameter, respectively.     

Facile Synthesis of (S,S)‐1,2‐Diacylamides and (S,S)‐1,2‐Diamines with C 2‐Symmetry

A series of chiral vicinal tertiary diacylamides with C ₂‐symmetry was synthesized from (S)‐α‐phenylethylamine, different aromatic aldehydes, and oxalyl chloride. The diacylamides obtained were then reduced to afford chiral vicinal diamines with C ₂‐symmetry. We propose that the diacylamides existed in four stable conformational isomers in solution because of the dihedral angle between acylamide bonds.     

Focal shift in radially polarized hollow Gaussian beam

Focal shift in radially polarized hollow Gaussian beam (HGB) with radial wavefront distribution is investigated theoretically. The wavefront phase distribution is cosine function of radial coordinate. Simulation results show that the intensity distribution in focal region of the radially polarized HGB can be adjusted considerably by the beam order of HGB n and cosine parameter C that indicates the phase change degree. On increasing C, focus can shift along optical axis and focal pattern changes remarkably. Focus may move in different direction under different condition. Focal shift distance fluctuates on increasing C, and fluctuation amplitude also increases simultaneously. In addition, threshold value of C for focal shift from one side to the other side of the paraxial focal plane differs for different n.     

硒(Ⅳ)-四乙基碘化铵-砷(Ⅲ)体系的极谱吸附波及其应用

报道了一个测定硒的高灵敏极谱吸附波新体系。在 ０． ７ ｍｏｌ／Ｌ ＨＢｒ溶液中，Ｓｅ（Ⅳ）－ （Ｃ２Ｈ５）４ＮＩ－Ａｓ（Ⅲ）体系于－０．６１Ｖ（ｖｓ．ＳＣＥ）处产生一高灵敏的极谱吸附波。峰电流与Ｓｅ （ Ⅳ）浓度在 ０． １～４０ μｇ／Ｌ范围内呈线性关系。检出限为 ０． ０５ μｇ／Ｌ。研究了极谱波的性质。 用本法测定了土壤中的全硒和有效硒，结果满意。     

线损管理系统中电网模型的建立

针对现有线损管理系统电网模型中存在的主配网没有直接连通、二次设备的测量作用没有被充分发挥的问题,提出了建设一种连通主配网、关联一次设备与二次设备的电网模型;通过一对一的数字化建模方法,建立一次设备与二次设备的分层模型连通主网、配网,除去等值连接的二次工作量和兼容性问题;设计二次设备的关口属性树建立一次设备与二次设备的关联关系,避免信息系统中关口与实际关口不符的问题;模型的搭建在SG-CIM的规范下进行;电网模型建立后,遵循SOA架构设计线损管理系统,实现电网模型的可重用管理及线损的实时管理。     

Polymer dewetting via stimuli responsive structural relaxation-contact angle analysis

Thin films of a stimuli-responsive homopolymer dewet as a stimulus response after anion exchange of the imidazolium's counter anion. Contact angle analysis and interfacial energy considerations indicate dewetting goes counter to increasing spreading coefficient. Intrafilm stress arising from structural relaxation drives the dewetting.     

Stimuli responsive poly(1-[11-acryloylundecyl]-3-methyl-imidazolium bromide): dewetting and nanoparticle condensation phenomena

A stimuli-responsive homopolymer poly(ILBr) is fabricated via a "two-phase" atom transfer radical polymerization (ATRP) process, where ILBr stands for the reactive ionic liquid surfactant, 1-[11-acryloylundecyl]-3-methyl-imidazolium bromide. An extraordinarily wide molecular weight distribution (PDI = 6.0) was obtained by introducing the initiator (4-bromomethyl methyl benzoate) in a heterogeneous two-phase process. The molecular weight distribution of poly(ILBr) was characterized by size-exclusion chromatography (SEC). The resulting homopolymer was found to be surface active and stimuli responsive. Poly(ILBr) films coated on quartz exhibit stimuli-responsive dewetting after ion exchange of Br(-) by PF(6)(-). This dewetting phenomenon can be understood in chain segmental terms as a stimuli-induced structural relaxation and appears to be the first such reported stimuli-responsive polymeric dewetting. Titrating aqueous poly(ILBr) with aqueous bis(2-ethylhexyl)sulfosuccinate induces nanophase separation and results in the condensation of nanoparticles 30-60 nm in diameter.     

微波法制备的茶籽壳基磁性生物质活性炭富集水样中的微囊藻毒素

本实验以茶籽壳为原料,Fe3 O4为磁性添加剂和微波吸收介质,采用微波辅助法制备磁性生物质活性炭(MBAC).实验结果表明,制备MBAC的最佳工艺条件为:50％的H3 PO4浸渍150目茶籽壳粉末,浸渍比为5∶1(V/m),活化后茶籽壳粉末与Fe3 O4的质量比为5∶2,微波功率为500 W.应用扫描电镜(SEM)、透...     

系数为缺项幂级数的高阶线性微分方程解的超级

In this paper,we investigate the hyper order of the solutions of high order linear differential equations with some dominated coefficient being lacunary series,and obtain some results which improve and...     

Ce促进Ni/SAPO-11催化剂上正庚烷的临氢异构化

通过浸渍法制备了Ni/SAPO-11催化剂, 并进一步通过分步浸渍法制备了Ni-Ce /SAPO-11双金属催化剂, 对其晶相结构和表面酸性进行了表征. 实验结果表明, Ce的引入导致比表面积和孔容增大, 总酸量升高而酸强度降低, 金属Ni在载体SAPO-11表面的分散度提高. 通过对正庚烷的临氢异构化反应研究发现, 引入Ce可以显著提高异庚烷的选择性. 在n(H₂)/n(n-C₇H₁₆)=12, MHSV=3.52 h^-1, 催化剂量0.3 g, 反应温度300 ℃条件下, Ni-2%Ce/SAPO-11催化剂的正庚烷转化率可达25.4%, 异庚烷的选择性可达90.4%.