离子色谱法测定甘草提取物中草酸的含量

建立了用离子色谱测定甘草提取物中残留草酸含量的新方法。选用DionexIonPacAS11-HC阴离子分析柱(250mm×4mmi.d.),淋洗液为18mmol/LNaOH溶液,流速为1.0mL/min,抑制电导检测器检测。草酸色谱峰面积(Y)与浓度(X)在1.004～10.04mg/L内线性关系良好,线性回归方程为Y=0.1939X-0.0326,相关系数r=0.9999,检出限为0.012mg/L。样品回收率为96.8%～98.6%,相对标准偏差为0.78%。该方法简便、快速。     

(NH4)2SiF6脱铝八面沸石酸性和1-已烯结碳研究

(NH_4)_2SiF_6液相同晶取代脱铝技术,作为沸石脱铝方法之一,自1985年提出后,己引起了人们的广泛注意.研究结果已表明:(NH_4)_2SiF_6脱铝沸石的结晶度很高,二次中孔道很少;由于在脱铝过程中扩散影响较大,使得脱铝沸石晶粒表面富硅.本文由(NH_4)_2SiF_6方法制备了骨架Si/Al 比在2.62～5.20的系列样品,用吡啶吸     

三核铜(Ⅰ/Ⅱ)配合物[Cu(en)_2]·[Cu(pht)_2]_2的合成、晶体结构及与DNA相互作用的研究

报道了多核铜配合物[Cu(en)_2]·[Cu(pht)_2]_2(Hpht:苯妥英,即5,5-二苯基-2,2-咪唑烷酮;en:乙二胺)的溶剂热合成、晶体结构及其与DNA的相互作用.该晶体属三斜晶系,P_1~-空间群,晶胞参数:a=0.8453(2)nm,b=1.1878(3)nm,c=1.5674(4)nm,a=101.197(3)°,β=97.690(3)°,γ=103.283(3)°,V=1.476(6)nm~3,D_c=1.480 g/cm~3,Z=1,F(000)=679,μ=1.139nm~(-1),R_1=0.0402,wR_2=0.0962[I>2σ(Ⅰ)],GOF=1.035.XPS和X射线单晶衍射数据显示该配合物分子由混价铜组成,包括两个一价铜和一个二价铜,其中每个Cu(Ⅰ)分别与两个苯妥英配体提供的氮原子配位,N-Cu(Ⅰ)-N的夹角为177°,一个Cu(Ⅱ)与六个配位原子配位(CuN_4O_2),形成一个稍变形八面体结构.配合物与DNA相互作用研究表明,该配合物主要是以插入方式与小牛胸腺DNA结合.     

共晶含能材料研究进展

共晶是不同种类的分子(两种或两种以上)通过氢键等分子间相互作用,形成具有特定结构和性能的多组分分子晶体,不同含能材料形成共晶可以有效改善炸药的感度、安全性等性能。针对目前高能炸药的改性需求,共晶在含能材料领域中的应用具有巨大的潜力。综述了共晶的形成原理及生长特性,总结了常见共晶的制备方法和表征方法,评述了含能材料共晶的研究现状和发展前景。     

巯基乙酸锑(Ⅲ)配合物合成与晶体结构

以三氧化二锑和巯基乙酸在水溶液中反应合成了配合物HSb(SCH2COO)2,并通过元素分析、红外光谱、X射线粉末衍射进行了表征,利用单晶X射线四圆衍射法测定了晶体结构,结果表明该配合物晶体属于单斜晶系,C2/c空间群,晶胞参数为:a=1.40005(8)nm,b=1.19121(8)nm,c=1.23588(8)nm,β=126.822(1)°,V=1.6499(2)nm^3,Dc=2.439g·cm^-3,Z=8,R1=0.0250。并对X射线粉末衍射数据进行了指标化,其结果与单晶数据吻合。     

十二烷基甜菜碱/十二烷基硫酸钠复配体系的表面活性

研究了两性表面活性剂十二烷基甜菜碱（C12BE）和阴离子型表面活性剂十二烷基硫酸钠（SDS）复配体系的形成胶束能力,降低表面张力效率,降低表面张力能力三种增效作用.发现C12BE和SDS摩尔比为6 :4时增效作用最显著.并考察了盐、醇对复配体系表面活性的影响,结果表明,加盐能导致表面活性的提高,加醇的机理比较复杂,乙醇对复配体系表面活性影响不大,而正丁醇影响则比较显著.     

Synthesis of CuS@CoS2 Double‐Shelled Nanoboxes with Enhanced Sodium Storage Properties

Metal sulfides have received considerable attention for efficient sodium storage owing to their high capacity and decent redox reversibility. However, the poor rate capability and fast capacity decay greatly hinder their practical application in sodium‐ion batteries. Herein, an elegant multi‐step templating strategy has been developed to rationally synthesize hierarchical double‐shelled nanoboxes with the CoS₂ nanosheet‐constructed outer shell supported on the CuS inner shell. Their structure and composition enable these hierarchical CuS@CoS₂ nanoboxes to show boosted electrochemical properties with high capacity, outstanding rate capability, and long cycle life.     

Rationally Designed Three‐Layered Cu2S@Carbon@MoS2 Hierarchical Nanoboxes for Efficient Sodium Storage

Hybrid materials, integrating the merits of individual components, are ideal structures for efficient sodium storage. However, the construction of hybrid structures with decent physical/electrochemical properties is still challenging. Now, the elaborate design and synthesis of hierarchical nanoboxes composed of three‐layered Cu₂S@carbon@MoS₂ as anode materials for sodium‐ion batteries is reported. Through a facile multistep template‐engaged strategy, ultrathin MoS₂ nanosheets are grown on nitrogen‐doped carbon‐coated Cu₂S nanoboxes to realize the Cu₂S@carbon@MoS₂ configuration. The design shortens the diffusion path of electrons/Na⁺ ions, accommodates the volume change of electrodes during cycling, enhances the electric conductivity of the hybrids, and offers abundant active sites for sodium uptake. By virtue of these advantages, these three‐layered Cu₂S@carbon@MoS₂ hierarchical nanoboxes show excellent electrochemical properties in terms of decent rate capability and stable cycle life.     

双中心全息记录的矢量分析与记录方向优化

对描述双掺杂晶体非挥发性全息记录动力学过程的Kukhtarev方程进行了矢量分析,分析中考虑了体光生伏特效应和外加电场的作用。在小信号近似的基础上给出了双中心全息记录中记录与固定阶段空间电荷场的矢量解析解。在综合考虑空间电荷场的各向异性以及晶体有效电光系数的各向异性后,给出了双中心全息记录的优化记录方向。结果表明,对(Fe,Mn)∶LiNbO3晶体633nm寻常光记录,优化记录方向主要由有效电光系数决定,光栅波矢与光轴夹角为22°,方位角为30°;对(Fe,Mn)∶LiNbO3晶体633nm非寻常光记录,优化记录方向主要由固定空间电荷场决定,光栅波矢与光轴夹角为44°,方位角为90°。     

Testifying experiment of the multi-pulse phenomena of capillary discharge soft-X-ray laser

In a capillary discharge experiment for the neon-like argon lasing, we have proposed an experimental scheme to verify that the multi-spike of X-ray diode (XRD) signal is a multi-pulse laser or is a reflection of the laser pulse in the XRD.The ceramic capillary has an inner diameter of 3mm and a length of 200mm.At the gas pressure of 28Pa and discharge current of 27kA, stable lasing has been realized.The experimental results prove that the multi-spike of XRD signal is a reflection of the electromagnetic signal produced by the laser pulse in the XRD.The improved electrocircuit scheme of the XRD to minimize the reflection phenomena is also found.