大豆分离蛋白结构与性能

大豆分离蛋白是大豆的重要组成部分,含有大量活性基团,具有可再生、可生物降解性等优点,可以成为制备环境友好材料的主要原料。由于大豆分离蛋白的组成和构象会对其功能特性产生明显的影响,因此对其结构和性能之间的关系进行系统的研究无疑会对材料学家在今后开发出新型的具有优异性能的大豆蛋白材料具有相当的帮助。本文首先介绍了大豆分离蛋白的组成、亚基的结构以及对其两种主要成分——β-大豆伴球蛋白（7S球蛋白）和大豆球蛋白（11S球蛋白）的分离方法;然后对大豆分离蛋白在不同条件下的构象研究和其主要物理化学性质,如溶解性和凝胶性的研究进展作了介绍;最后对大豆分离蛋白在薄膜、纤维和塑料等材料领域的应用进行了简要的综述。     

Swimming Mode of Two Interacting Squirmers under Gravity in a Narrow Vertical Channel

The swimming mode of two interacting squirmers under gravity in a narrow vertical channel is simulated numerically using the lattice Boltzmann method (LBM) in the range of self-propelling strength 0.1 ≤ α ≤ 1.1 and swimming type −5 ≤ β ≤ 5. The results showed that there exist five typical swimming patterns for individual squirmers, i.e., steady upward rising (SUR), oscillation across the channel (OAC), oscillation near the wall (ONW), steady upward rising with small-amplitude oscillation (SURO), and vertical motion along the sidewall (VMS). The parametric space (α, β) illustrated the interactions on each pattern. In particular, the range of oscillation angle for ONW is from 19.8° to 32.4° as α varies from 0.3 to 0.7. Moreover, the swimming modes of two interacting squirmers combine the two squirmers’ independent swimming patterns. On the other hand, the pullers (β < 0) attract with each other at the initial stage, resulting in a low-pressure region between them and making the two pullers gradually move closer and finally make contact, while the result for the pushers (β > 0) is the opposite. After the squirmers’ interaction, the squirmer orientation and pressure distribution determine subsequent squirmer swimming patterns. Two pushers separate quickly, while there will be a more extended interaction period before the two pullers are entirely separated.     

3D Porous Structure-Inspired Lignocellulosic Biosorbent of Medulla tetrapanacis for Efficient Adsorption of Cationic Dyes

The focus of this work was on developing a green, low-cost, and efficient biosorbent based on the biological structure and properties of MT and applying it to the remediation of cationic dyes in dye wastewater. The adsorption performance and mechanism of MT on methylene blue (MB) and crystal violet (CV) were investigated by batch adsorption experiments. The results demonstrated that the highest adsorption values of MT for MB (411 mg/g) and CV (553 mg/g) were greatly higher than the reported values of other biosorbents. In addition, the adsorption behaviors of methylene blue (MB) and crystal violet (CV) by MT were spontaneous exothermic reactions and closely followed the pseudo-second-order (PSO) kinetics and Langmuir isotherm. Further, the depleted MT was regenerated using pyrolysis mode to convert depleted MT into MT-biochar (MBC). The maximum adsorption of Cu²⁺ and Pb²⁺ by MBC was up to 320 mg/g and 840 mg/g, respectively. In conclusion, this work presented a new option for the adsorption of cationic dyes in wastewater and a new perspective for the treatment of depleted biosorbents.     

Changes in Chemical Composition of Flaxseed Oil during Thermal-Induced Oxidation and Resultant Effect on DSC Thermal Properties

To investigate the changes in chemical composition of flaxseed oil during thermal-induced oxidation and the resultant effect on thermal properties, samples with different oxidation levels were obtained by being heated at 180 °C for two hours and four hours. The oxidation degree was evaluated using peroxide value (PV), extinction coefficient at 232 nm and 268 nm (K₂₃₂ and K₂₆₈), and total polar compounds (TPC). Using chromatography, the fatty acid profile and triacylglycerol (TAG) profile were examined. Differential scanning calorimetry (DSC) was used to determine the crystallization and melting profiles. Thermal-induced oxidation of flaxseed oil led to a significant increase (p < 0.05) in PV, K₂₃₂, K₂₆₈, and TPC, but the relative content of linolenic acid (Ln) and LnLnLn reduced dramatically (p < 0.05). TPC derived from lipid degradation affected both crystallization and melting profiles. Statistical correlations showed that the onset temperature (T_on) of the crystallization curve was highly correlated with K₂₃₂, TPC, and the relative content of LnLnLn (p < 0.05), whereas the offset temperature (T_off) of the melting curve was highly correlated with the relative content of most fatty acids (p < 0.05). This finding provides a new way of rapid evaluation of oxidation level and changes of chemical composition for flaxseed oils using DSC.     

XIPAF磁铁电源电流纹波对慢引出的影响

从理论和模拟两方面研究了西安质子应用装置二极铁、四极铁电源电流纹波对引出束流的影响,并根据模拟结果确定出以下单种磁铁电源电流纹波标准：对于聚焦四极铁电源,电流纹波/设定值应小于1.2×10^-4;对于散焦四极铁电源,电流纹波/设定值应小于2×10^-3;对于二极铁电源,电流纹波/设定值应小于4×10^-4。因西安质子应用装置同步环上所有磁铁电源采用同一纹波标准,综合考虑所有磁铁电源电流纹波后,最终确定电源电流纹波/设定值应小于1×10^-4。     

万焦耳激光装置上多热力学路径高压加载技术实验研究

针对极端高压条件物质特性研究需求,在我国万焦耳激光装置上利用其高能量、高功率、任意整形长脉冲输出的技术优势先后开展了冲击压缩、准等熵压缩以及“预冲击准等熵压缩”复合热力学路径压缩等多种热力学路径的高压加载技术研究,建立了实用的高压加载设计方法,重点优化了高压加载源的平面性和干净性,发展了高压状态精密表征技术,实现了10¹¹ Pa以上准等熵,10¹² Pa以上冲击以及两种路径之间的宽区高压加载状态能力,为激光装置上的高压状态方程及相变动力学研究提供了重要的技术基础。     

带2k个周期径向裂纹的圆形孔口问题的精确分析解

利用复变函数的方法,通过构造保角映射研究了带2k个周期径向裂纹的圆形孔洞的平面弹性问题,给出了裂纹尖端应力强度因子的解析解.并由此模拟出了十字裂纹,米字裂纹,带单裂纹、对称双裂纹、对称四裂纹、对称八裂纹的圆形孔洞,共点周期裂纹问题.     

Preparation of multi-walled carbon nanotubes functionalized magnetic particles by sol-gel technology and its application in extraction of estrogens

Magnetic silica particles coated with hydroxy-terminated multi-walled carbon nanotubes (MWCNTs-OH) were prepared by sol-gel technology, characterized and used for the convenient, rapid and efficient extraction of several estrogens (including diethylstilbestrol, estrone and estriol) in water followed by sweeping micellar electrokinetic chromatography analysis with UV detection. The results demonstrated that sol-gel technology was a feasible, simple and effective technique for the preparation of MWCNTs-OH functionalized magnetic silica particles. The factors affecting the extraction efficiency of estrogens (the pre-activation of magnetic particles, adsorption time, desorption time and the amount of elution solvent) were carefully investigated. The extraction efficiencies for diethylstilbestrol, estrone and estriol were 95.9%, 93.9%, and 52.4%, respectively, under the optimum conditions. The method detection limits for the three estrogens were less than 0.2 ng mL⁻¹. The developed method was applied for the analysis of tap water, mineral water, Pearl River water and honey.     

萘磺酸盐与β-环糊精衍生物的包结行为

以自组装方式在石英晶体谐振器的金电极表面修饰末端含巯基的β 环糊精衍生物（β CDd）,用石英晶体微天平（QCM）在线监测α 、β 萘磺酸盐与之发生包结反应的过程,探讨了温度、浓度、取代基位置对包结反应稳定常数Kin和速率常数ka的影响.从理论上推导并通过实验验证了Kin和ka所遵从的关系式.结果表明：所形成的包结配合物中β CDd与萘磺酸盐的化学计量均为1:1;包结配位反应过程符合Langmuir吸附模型;取代基在萘环上的位置对Kin和ka有很大影响,说明不同取代位置的萘磺酸盐与β CDd的包结行为存在明显差异.