KCaA型分子筛制备及其对CO2吸附性能的研究

采用离子交换法,在CaA型分子筛中加入氯化钾水溶液,并搅拌一定时间,将功能K+引入到CaA型分子筛结构中,以调控CaA型分子筛的孔径和增加它的吸附活性位点.考察了离子交换时间和气体吸附压力等条件对制备的KCaA型分子筛的结构、形貌和CO2吸附性能的影响.通过X射线衍射、扫描电子显微镜和CO2吸附等温线等表征手段,结果发现:获得的KCaA型分子筛具有与CaA型分子筛相同的结构与形貌;增大气体吸附压力,分子筛对CO2的吸附量增大;但随着离子交换时间的增长,分子筛对CO2的吸附能力先增大后减小;在室温及1bar气压下对CO2气体的吸附性能比原CaA型分子筛提高了26.7%.     

超大孔离子交换制备色谱分离纯化高活性凝血因子VIII

建立了一条从人血浆中分离高活性凝血因子VIII(FVIII)的纯化工艺。基于FVIII和介质孔径的尺度比及其对蛋白质活性影响的分析,设计了以超大孔离子交换制备色谱为核心步骤的新型分离纯化工艺。分别进行超大孔离子交换色谱与传统离子交换色谱的条件优化,并对优化工艺所得产品进行了活性检测(底物显色法)和纯度检测(高效凝胶过滤和凝胶电泳)。结果表明,超大孔介质结构不但可以有效地保护蛋白质大分子结构,而且能够大幅度地提高制备色谱的传质速率,从而得到具有高凝血活性的FVIII产品。FVIII在超大孔制备色谱过程中的回收率(85%)比传统离子交换制备色谱高4～5倍,产品比活高达154 IU/mg。此外,还研究了超大孔介质的再生程序,采用5个柱体积的1 mol/L NaOH低流速清洗色谱柱,保证了色谱工艺的稳定性。本纯化工艺步骤简单,重现性好,易于放大生产。     

Fluctuation relations for heat exchange in the generalized Gibbs ensemble

In this work, we investigate the heat exchange between two quantum systems whose initial equilibrium states are described by the generalized Gibbs ensemble. First, we generalize the fluctuation relations for heat exchange discovered by Jarzynski and Wójcik to quantum systems prepared in the equilibrium states described by the generalized Gibbs ensemble at various generalized temperatures. Secondly, we extend the connections between heat exchange and the Rényi divergences to quantum systems under generic initial conditions. These relations are applicable for quantum systems with conserved quantities and universally valid for quantum systems in the integrable and chaotic regimes.     

Determination of Water and Solute Transport in Polyacrylamide Gels

Summary: Water exchange between five polyacrylamide gels (Bulkamid®, Aquamid®, Rectamid®, HV-PAAG, Acuvue) with a physiological salt solution was determined by means of tritium-labeled water. Urea and chloride exchange was also determined in Acuvue. The method was a modified version to measure rapid transport processes in red blood cells. The study shows that water and solutes easily exchange between the hydrogel under study and the surrounding medium, independent of the solid polymer content (2.5–40 wt%) and an over ten-fold variation of the cross-linking density.     

Adsorption Behavior of Metal Ions by Amidoxime Chelating Resins

In this work, the acrylonitrile (AN) – divinylbenzene (DVB) –methylacrylate (MA) resin was synthesized via suspension polymerization in the presence of toluene as diluent, and benzoylperoxide (BPO) as initiator. The effect of MA, toluene and alkaline treatment on the exchange capacity of the resin were investigated. The results showed that the anion exchange capacity decreased with an increase in the amount of MA, while alkaline treatment had no significant effect. Also, the cation exchange capacity increased with an increase in the amount of hydrophilic agent and reached a maximum point. The sorption equilibrium was achieved relatively fast within 40 mins, and the resin exhibited affinity towards lead (II), copper (II) and in particular uranium (VI). The adsorption of uranium was directly depended up on the pH value. Furthermore, the macroreticular chelating resin, containing amidoxime group had higher adsorption of uranium (VI) in comparison to other metal ions studied. Finally, the alkaline treatment enhanced the potential for much faster adsorption characteristics and the highly porous chelating resin provided a more favorable pore structure for the rapid rate of diffusion of metal ions.     

人民币汇率波动对我国出口价格的传递效应研究——区分持久性与暂时性汇率变动的不同影响

实体经济的变化和货币政策与金融市场的扰动,分别造成汇率的持久性变动与暂时性变动。为了研究这两种不同的汇率变动对出口价格产生的影响,本文通过研究不完全竞争市场中出口企业的定价行为,建立理论分析框架,并使用Blanchard-Quah方法对汇率变动进行分解,得出两种不同的汇率变动。基于VEC模型,采用1997年1月至2012年12月我国的出口价格数据进行实证分析,结果表明:人民币实际有效汇率的持久性变动和暂时性变动对我国出口价格的传递系数分别为0.84和0.67。因此,加快出口行业的转型与升级以及维持好货币政策与金融市场的稳定,对降低汇率波动对我国出口企业的影响具有重要的意义。     

铂合金纳米立方块催化剂的氧还原反应活性比较

氧还原反应是质子交换膜燃料电池和金属-空气电池的重要反应,贵金属铂（Pt）与元素周期表中第一排的非贵过渡金属（M）形成铂合金催化剂（PtM）可以提高氧还原反应活性. 但是,有关活性的提高有多大程度上是来自合金元素的贡献却仍然存在争议. 为了研究合金元素对PtM催化活性的影响,本工作合成了颗粒形状与合金元素含量相似的铂锰（PtMn）, 铂铁（PtFe）, 铂钴（PtCo）和铂镍（PtNi）纳米立方块催化剂,并考察了不同铂合金催化剂在酸性介质中的氧还原反应活性. 选择制备立方块形状纳米颗粒催化剂进行比较,可以将颗粒表面结构对催化活性的影响降到最小. 结果表明,氧还原反应活性与铂d-带中心值曲线呈现火山形关系,其中PtCo纳米立方块催化剂的活性最高. 本文所得到的实验结果与基于d-带理论框架已知表面的密度泛函理论计算结果一致.     

Effect of Sulfonation Degree on Performance of Proton Exchange Membranes for Direct Methanol Fuel Cells

A series of proton exchange membranes based on sulfonated polyarylene ether ketones(SPAEKs) was used to study the effect of sulfonation degree on proton conductivity, methanol permeation and performance of direct methanol fuel cells(DMFCs). Dependences of physical characteristics of the membranes, i. e., proton conductivity, water uptake, swelling ratio, methanol permeability and ion exchange capacity(IEC) were systematically studied. Both methanol permeability and proton conductivity of the SPAEK membrane grow rapidly as the increase in sulfonation degree since methanol molecules and protons share the same transfer channel. However,the methanol permeability plays more important role comparing to proton conductivity. As a result, the SPAEK membrane with a medium sulfonation degree(60%) was found to yield the best performance in a DMFC due to the acquirement of balanced conductivity and methanol permeability.     

The investigation of the bitumen from ancient Greek amphora using FT ICR MS,H/D exchange and novel spectrum reduction approach.

Recently Russian archeologists have discovered on Taman peninsula an ancient (V B.C.) Greek amphora full of dense bitumen. This is the oldest amphora in the world that contains bitumen. We report the investigation of this bitumen using ultrahigh resolution Fourier transform mass spectrometry. Also we used recently developed in‐ESI source Hydrogen/Deuterium exchange approach for the structural characterization of the individual molecules and estimation of the biodegradation of the bitumen. The increase of number of the labile hydrogens compared to the non‐degraded oil can serve as an additional evidence of the degradation of bitumen via oxidation. For the facilitation of the spectrum processing we have developed the special iterative spectrum reduction approach. It was observed that molecules that have only oxygen heteroatoms possess two –OH groups what is unusual for the petroleum. Based on this we suggested that the bitumen degraded during its being in amphora for 2500 years. Copyright © 2016 John Wiley & Sons, Ltd.     

碳酸钠-氧化锌熔矿离子交换电感耦合等离子体-质谱法测定土壤样品中的碘

通过碳酸钠-氧化锌熔矿,电感耦合等离子体-质谱法测量土壤样品中碘的含量。系统讨论分析了熔矿温度的影响、离子交换树脂用量及交换时间的优化、记忆效应消除、乙醇对灵敏度的增强效应、测量元素校准的选择以及标准曲线基体匹配等实验条件对分析结果的影响。经国家一级标准物质分析验证,该方法对于碘含量大于5μg／g的样品具有很大优势,不需稀释即可直接测量准确,结果较满意,对今后碘的分析测定时的注意事项有较好的引导作用。