水平极化光在单轴吸收晶体中的传播

根据光在各向同性吸收介质中传播的分析方法,引入了波法线矢量传播常量,讨论了水平极化光在单轴吸收晶体中的传播规律,得到了波法线折射率、光线折射率、吸收系数等描述吸收晶体性质和光传播性质的物理量的表达式,推导出透明晶体的相应公式.数值计算表明,由该法得到的晶体表面的反射和透射系数与用复折射率表示法得到的结论一致.     

铝-镉-铜三元系富铜合金相图

铝-镉-铜三元系富铜合金相图的室温固相截面已用X-射线方法测定。合金含量最高达30％(重量)铝及30％镉。室温相截面由五个单相区α,γ₂,δ,ζ₂,η₂;十个两相区α+β,α+γ₂,β+γ₂,γ₂+δ,β+δ,δ+ζ₂,ζ₂+η,η₂+δ,η₂+β,η₂+θ及四个三相区α+β+γ₂,β+γ₂+δ,β+δ+η₂,δ+ζ₂+η₂所构成。没有发现新相。     

介孔CuO/γ-Al2O3催化剂的 制备及其在合成气制二甲醚反应中的应用

以三嵌段共聚物F₁₂₇为模板剂,以异丙醇铝、硝酸铜为原料,采用溶剂挥发自组装法制备具有介孔结构的CuO/γ-Al₂O₃复合催化剂.通过XRD、SEM-EDS、H₂-TPR、N₂-吸附脱附、TEM等技术对该催化剂的结构进行了表征.实验结果表明,通过溶剂挥发自组装法制备的催化剂CuO/γ-Al₂O₃具有有序的介孔结构,并且具有较大的比表面积以及均一的介孔结构,并且Cu元素均匀地分布在γ-Al₂O₃的表面.将该复合催化剂用于合成气直接制备二甲醚的反应,在空速1 500 h^-1、温度320 ℃、压力5 MPa的条件下,CO转化率最高达到68.8%、DME选择性达到59.0%.连续反应50 h后,CO转化率从68.8%降低至59.5%,DME选择性基本保持不变,催化剂部分失活的原因是由于铜元素部分发生了聚集.     

动叶尾迹对跨声速压气机静叶非定常分离结构的影响研究

采用数值模拟的方法研究了动叶尾迹对跨声速压气机设计工况下静叶表面和下端壁分离结构的非定常影响规律。首先,采用Rotor37的实验结果验证了数值模拟方法的可靠性。通过对跨声速压气机设计工况的计算,认为定常计算和非定常计算的结果整体上是相似的,非定常计算考虑了动叶尾迹对静叶流场的影响。研究表明,动叶尾迹在向下游输运过程中经历了拉伸、扭曲、积聚和耗散的过程。动叶尾迹使动静叶交界面气流角发生周期性波动。动叶尾迹的扫掠,使静叶前缘闭式分离区域范围发生先增大后减小的周期性波动,使静叶尾缘分离形式呈现由闭式分离向开式分离的周期性转化。动叶尾迹的扫掠在马蹄涡吸力面分支前诱导出一个小尺度的旋涡,并使得静叶根部尾缘和下端壁角区处的螺旋点拓扑结构呈周期性变化。动叶尾迹的扫掠使得静叶压力面的局部高静压区发生周期性的迁移。     

Construction of Tetrathiafulvalene-based Covalent Organic Frameworks for Superior Iodine Capture

The effective capture of radioiodine species during nuclear fuel reprocessing and nuclear accidents is of primary importance but remains challenging for the sustainable development of nuclear energy. Herein, we report two newly designed two-dimensional(2D) and three-dimensional(3D) covalent organic frameworks by introducing tetrathiafulvalene functional groups into the building units for the simultaneous physisorption and chemisorption capture of iodine molecules. Remarkably, the obtained 3D TTF-TAPT-COF material exhibited a superior iodine vapor adsorption capacity of up to 5.02 g/g at 348 K and under ambient pressure and an adsorption kinetics of 0.515 g/(g∙h), surpassing most of other materials reported so far. The strong physiochemical interactions between iodine molecules and the frameworks of the obtained COFs were revealed by a set of experimental techniques. This study provides a feasible approach for the rational design and the construction of novel and effective COF-based adsorbents for iodine enrichment and related environmental remediation.     

A general and efficient FeCl3-catalyzed nucleophilic substitution of propargylic alcohols

A general and efficient FeCl3-catalyzed substitution reaction of propargylic alcohols with carbon- and heteroatom-centered nucleophiles such as allyl trimethylsilane, alcohols, aromatic compounds, thiols, and amides, leading to the construction of C-C, C-O, C-S and C-N bonds, has been developed.     

Highly sensitive response to dopamine at a modified electrode involving a composite film with Au nanoparticles dispersed in a fluorocarbon polymer

A new approach for the highly sensitive detection of dopamine by a novel composite film involving gold nanoparticles trapped in a negatively-charged fluorocarbon polymer (Nafion) on a glassy carbon (GC) electrode fabricated by a simple method is described. Gold nanoparticles with an average diameter of 2.3 nm ± 0.2 nm are dispersed throughout the whole Nafion film. The introduction of gold nanoparticles into the Nafion film not only gives a highly active electrode surface area but also increases the conduct...     

(S)-4-苄基-2-噁唑烷酮的合成工艺改进

以L-苯丙氨酸为原料,经还原和关环反应合成了(S)-4-苄基-2-噁唑烷酮,总收率66%,其结构经1HNMR,13C NMR和HR-MS表征。     

Expression and Characterization of a Recombinant Truncated Capsid Protein of Hepatitis E Virus in Pichiapastoris

Hepatitis E is an enterically transmitted viral disease caused by infection with hepatitis E virus(HEV).HEV is a nonenveloped virus that has been classified in the family of Caliciviridae.The virus appears to be a polyadenylated,positive-stranded RNA virus with three major open reading frames(ORFs).The capsid protein of HEV is encoded by the open reading frame 2(ORF2).We attempted to produce a truncated capsid protein,designed p293,in Pichia pastoris.The p293 gene encoding amino acids(aa) 382-674 of HEV ORF2 was designed based on the full length of HEV ORF2,cloned into the yeast vector pPIC9K,and expressed in P.pastoris strain GS115.SDS-PAGE and Western blotting demonstrated that the recombinant protein p293 could well be expressed in P.pastoris.Under optimized conditions (culture medium pH,6.0―6.5;methanol concentration added daily,3.0%;inoculum density,OD600=60;induction time point,72―96h),the yield of soluble p293 was approximately 80 mg/L.We also observed p293 secretory expressed in P.pastoris to be 30 nm viral like particles by using electron microscopy.These results show that the p293 may has utility in the analysis of cell specific factors in the protein processing and assembly of HEV,and serve as a useful antigen for both diagnostic and vaccine purposes.     

6-(4-氯苯氧基)四唑并[5,1-a]酞嗪的核磁共振谱峰归属

为确保具有独立知识产权的国家级一类抗癫痫创新候选药物的药品安全,采用500 MHz核磁共振（NMR）技术,结合规范不变原子轨道-核磁共振（GIAO-NMR）量子化学计算方法,对进入临床阶段的抗癫痫药6-（4-氯苯氧基）四唑并[5,1-a]酞嗪的¹H NMR、¹³C NMR和¹⁵N NMR信号进行了归属,从而为安全用药提供了精确结构信息．线性回归对比表明,标度法计算的NMR化学位移与实验值吻合较好．