COMPLEX STABILITY OF SUGARS AND SUGAR ALCOHOLS WITH Na + , Ca 2+ , and La 3+ IN CHROMATOGRAPHIC SEPARATIONS USING POLY(STYRENE- CO -DIVINYLBENZENE) RESINS AND AQUEOUS ORGANIC ELUENTS

The complex formation between metal ions and carbohydrates in solvent mixtures has been studied by chromatographic measurements. The effect of noncomplexing partition was decreased by attaching the active groups only on the shell of the stationary phase particles. Poly(styrene- co -divinylbenzene) resin beads were surface-sulfonated for that purpose. Thus the inner part of the sulfonated bead remained inactive and nonswellable. The counter-ions examined were Na + , Ca 2+ , and La 3+ , and the organic cosolvents were ethanol and acetonitrile. The stability constants of the very weakly complexing D -glucose, D -xylose, and L -rhamnose, the weakly complexing D -fructose and L -arabinose, and the strongly complexing xylitol and D -sorbitol were determined. The increasing organic cosolvent content increased the retention times, which is explained by the increased complex stability between the complexing solute and the counter-ion. The effect was greatest for the complex-forming sugars in the Ca 2+ form and for the sugar alcohols in the La 3+ form. The organic cosolvent had only a minor effect on the weakly complexing components, whereas the complex stability of the strongly complexing xylitol and sorbitol in 50 wt% ethanol solution in the La 3+ resin was more than five times higher compared to the stability measured in pure water.     

Measurement and correlation of solubility of xylitol in binary water+ethanol solvent mixtures between 278.00 K and 323.00K

The solubility of xylitol in ethanol+water solvent mixtures was measured at temperatures ranging from 278.00 K to 323.00 K at atmospheric pressure by using a laser technique. The results of these measurements were correlated by the combined nearly ideal binary solvent CNIBS/Redlich-Kister equation. The experimental solubility and correlation equation in this work can be used as essential data and models in the purification process of xylitol. The variant 2 in the CNIBS/R-K models was confirmed to be more adaptable to predict solubility of xylitol in binary ethanol +water system. Using the experimentally measured solubilities, the thermodynamic properties of dissolution of xylitol, such as Gibbs energy, molar enthalpy of dissolution, and molar entropy of dissolution, were calculated.     

一种乙醇柴油的微乳化性能研究

针对乙醇与柴油互溶性差的特点,采用添加表面活性剂脂肪醇聚氧乙烯醚（AEO3）和助溶剂正戊醇的方法,改变乙醇柴油的微乳化性能。并通过实验考察了它们的最佳复配比,通过乙醇、柴油、稳定剂体系的拟三元相图,考察了温度对其稳定性的影响。最后对乙醇柴油的主要物性进行了测定。通过一系列实验得知,醇类可以作为乙醇柴油混合燃料的助溶剂,正戊醇的助溶效果相对较好;随着温度的降低,乙醇柴油的微乳化液会逐渐变浑浊,最终会分离;乙醇、助溶剂和表面活性剂的加入会降低乙醇柴油的闪点;表面活性剂AEO3作为乳化剂,在醇类稳定剂助溶下（例如AEO3：正戊醇=1：4）制成的乙醇柴油微乳液,稳定时间可达二个月以上。     

水样中痕量铜的富集和测定的研究

铜离子与1-(2-吡啶偶氮)-2-萘酚(PAN)反应,生成疏水性的络合物,在助溶剂乙醇的作用下,被萃取到三氯甲烷相中,用分光光度法测定三氯甲烷相中的Cu2+-PAN,建立了析相富集-分光光度法测定水样中痕量铜的分析方法。对影响络合反应和相分离的各种条件进行了优化。在选择的实验条件下,铜的质量浓度在0.50～15μg/mL范围内与吸光度呈线性关系,相关系数为0.999 57,方法的检出限为0.089μg/mL,对铜浓度为5.0μg/mL的样品溶液进行7次平行测定,相对标准偏差为1.67%。该方法用于水样中铜的测定,回收率在95.6%～101.5%之间。     

高纯度绿原酸的稳定性研究

目的：研究高纯度绿原酸在不同条件下的稳定性。方法：采用高纯度绿原酸在抗氧化剂（亚硫酸氢钠、焦亚硫酸钠、L一半胱胺酸盐、维生素c）、不同pH值磷酸盐缓冲液、有机溶剂（甲醇、乙醇）、金属铜离子及络合剂及13一环糊精中的稳定性。结果：绿原酸在抗氧化剂L一半胱胺酸盐中最稳定,在酸性环境较碱性环境中更稳定,在上述有机溶剂中稳定,...     

除镍离子交换树脂的优选及其效能的研究

为优选除Ni~(2+)交换树脂,采用电镀镍废水(Ni~(2+)的质量浓度为80 mg/L)研究了5种阳离子交换树脂对Ni~(2+)的吸附等温式和吸附动力学,考察了其对电镀镍废水中Ni~(2+)的吸附交换容量、吸附交换速率、再生性能以及废水中共存离子对树脂处理电镀镍废水效能的影响。结果表明,在120 min内5种阳离子树脂对Ni~(2+)的吸附基本达到平衡,吸附等温线均符合Freundlich吸附,吸附动力学均遵循准二级动力学方程;KP752和CH-90树脂对Ni~(2+)吸附交换容量分别为22.421和22.831 mg/g,吸附效果最好,并且2种树脂对Ni~(2+)的回收率都可达80%以上;共存的Ca~(2+)、Mg~(2+)会显著影响CH-90树脂吸附Ni~(2+)的效果,而对KP752树脂的影响较小。     

彩印纸板醇溶快干上光涂料的研制

以氨基树脂585-1、0.5 s硝化棉为成膜物质,再加入助溶剂、催干剂,并以无水乙醇作为稀释剂进行溶合,制得一种醇溶性纸张上光涂料。讨论了树脂、硝化棉、助溶剂、催干剂等组分及其用量对涂料性能的影响。结果表明:树脂、硝化棉、助溶剂、催干剂配比为4∶10∶21∶1时,上光涂料的干燥速率最大,涂膜综合性能良好。     

Stabilization and activation of {alpha}-chymotrypsin in water-organic solvent systems by complex formation with oligoamines

Formation of enzyme–oligoamine complexes was suggestedas an approach to obtain biocatalysts with enhanced resistancetowards inactivation in water–organic media. Complex formationresults in broadening (by 20–40% v/v ethanol) of the rangeof cosolvent concentrations where the enzyme retains its catalyticactivity (stabilization effect). At moderate cosolvent concentrations(20–40% v/v) complex formation activates the enzyme (by3–6 times). The magnitude of activation and stabilizationeffects increases with the number of possible electrostaticcontacts between the protein surface and the molecules of oligoamines(OA). Circular dichroism spectra in the far-UV region show thatcomplex formation stabilizes protein conformation and preventsaggregation in water–organic solvent mixtures. Two populationsof the complexes with different thermodynamic stabilities werefound in -chymotrypsin (CT)–OA systems depending on theCT/OA ratio. The average dissociation constants and stoichiometriesof both low- and high-affinity populations of the complexeswere estimated. It appears that it is the low-affinity siteson the CT surface that are responsible for the activation effect.     

非均相Fenton催化剂的制备及其对含铜废水的处理研究

以D072型树脂为载体制备非均相Fenton催化剂,并研究了该催化剂在氧化剂作用下对含铜废水的处理效果。在催化剂制备阶段,D072型树脂吸附Fe~(2+)的平衡时间为60min。当Fe~(2+)的质量浓度为1 200mg/L时,D072型树脂上负载的Fe~(2+)量基本不变,载铁量达到107.42mg/g,并且温度对催化剂载铁量的影响不大。对于100mg/L的含铜废水,最佳的处理条件为:pH值3,催化剂的投加量15g/L,H_2O_2的质量浓度672mg/L,反应温度30℃,反应时间90min。在此条件下,Cu2+的去除率可达到87.17%。催化剂在多次使用后处理效果依旧良好,但处理速率每次都有所下降。     

Morphology,mechanical property,and processing thermal stability of PVC/La‐OMMTs nanocomposites prepared via in situ intercalative polymerization

Poly(vinyl chloride) (PVC) nanocomposites were prepared via an in situ intercalative suspension polymerization of vinyl chloride with four organic carboxylic acid salts (montmorillonite [MMT] units) containing thermally stable lanthanum ions. The effects of different lanthanum organic montmorillonites (La‐OMMTs) on the particle features and molecular weight were investigated. The transmission electron microscopy data indicated the formation of partially exfoliated or intercalated PVC/La‐OMMTs nanocomposites. The effect of different functional groups on the mechanical properties and processing thermal stability of PVC/La‐OMMT nanocomposites were investigated. Tensile testing and two‐roll mill processing results showed that La‐OMMTs could enhance the dynamic thermal stability and mechanical properties versus PVC pure resin and PVC/I.30P nanocomposites (composed of PVC and I.30P). This suggested that the double bond and amidogen group in La‐OMMTs could promote the dispersion of La‐OMMTs in the PVC matrix and also improve the adhesion between the La‐OMMTs and PVC matrix. The results have potential value in the industrial development of PVC/La‐OMMTs nanocomposites. J. VINYL ADDIT. TECHNOL., 26:97–108, 2020. © 2019 Society of Plastics Engineers     

乙醇柴油的微乳化研究

乙醇柴油的开发有助于缓和石油系燃料的供需矛盾,同时乙醇柴油的使用可以减轻汽车尾气对大气的污染。为提高乙醇柴油的稳定性,文章采用乳化与互溶法制备在一定温度范围内稳定存在的乙醇柴油微乳液,研究了不同表面活性剂和助溶剂对该体系的乳化和助溶效果,并探讨了温度对该体系的影响。在此基础上,对表面活性剂AEO-3与正庚醇的复配效果进行研究。     

The Use of 24-Crown-8's in the Solvent Extraction of CsNO3 and Sr(NO3)2

Abstract

The feasibility of a solvent extraction process for removing strontium and cesium from acidic high activity nuclear waste is shown. Both strontium and cesium can be extracted from an aqueous HNO₃ phase containing the metal nitrates into an organic phase containing kerosene or CCl₄ as a diluent and complexing agents dissolved in the diluent. The most promising results obtained thus far have required the use of a mixture of three metal complexing agents: tributyl phosphate, di-2-ethylhexyl phosphoric acid, and 4,4′(5′)-di-tert-butylbenzo-24-crown-8. The highest distribution coefficients obtained (organic/aqueous) were 1.45 ± 0.05 for Cs⁺ and 200 for Sr²⁺. The extraction is reversible and is strongly dependent on the pH of the aqueous phase. The metal can be removed from the organic phase by lowering the pH to 1, while raising the pH above 3 causes the metal to return to the organic phase. The utility of this extraction technique for nuclear processing will depend on the radiation stability of the complexing agents and the degree of selectivity obtained when extracting strontium and cesium from mixed fission products.     

改性芳纶纬编增强体复合材料力学性能的研究

为探讨芳纶纬编增强体复合材料的力学性能,以对位芳纶为原料,采用LiCl/无水乙醇溶液对芳纶表面进行改性处理,设计并编织1+1满针罗纹和罗纹空气层2种组织织物增强体,以E-51环氧树脂为基体,应用手糊成型技术制备芳纶纬编增强体平板复合材料。采用YG026D型电子织物强力机对制备的芳纶纬编增强体复合平板材料的经纬向拉伸、弯曲、压缩以及层间剪切性能进行测定。结果显示:经LiCl/无水乙醇络合溶液处理的芳纶纬编增强体复合材料的各项力学性能均有所提高,且经向的各项力学性能优于纬向。在拉伸、弯曲性能方面,罗纹空气层芳纶纬编增强体平板复合材料优于1+1满针罗纹芳纶纬编增强体复合材料。     

对羟基苯甲酸稀土(铕)配合物及其荧光纤维的制备

合成了Eu3+与对羟基苯甲酸、1,10-邻菲啰啉(phen)的具有新型结构的稀土配合物。通过TEM、元素分析、IR、TG及荧光光谱分析对其表观形貌、粒径、组成结构及荧光性能进行了分析表征。结果表明:对羟基苯甲酸稀土配合物呈球状,粒径在100nm左右;配合物具有良好的热稳定性。配合物的荧光发射峰分别与稀土铕5D0→7FJ(J=0,1,2,4)的跃迁相对应,最强发射峰位于616.3nm处。将制得的配合物与聚丙烯树脂进行熔融纺丝,制得稀土荧光纤维。测试结果表明:纤维具有优异的荧光性能,最强发射峰位于618nm处,是Eu3+的特征红色发射谱带。     

交联羧甲基壳聚糖树脂对稀土离子吸附性能研究

以羧甲基壳聚糖为原料，经戊二醛交联制备阳离子型树脂，考察了其对稀土离子La^3 、Nd^3 、Sm^3 、Lu^3 吸附性能。探讨了溶液的酸度、体系温度、初始离子浓度及离子强度对该树脂吸附性能的影响；发现羧甲基壳聚糖经戊二醛交联制成的树脂对稀土离子有较强的吸附性，最高吸附率可达99％以上，并且具有良好的重复使用性；其吸附性为满足Langmuir或Freumdilich等温式。     

Synthesis and Surface Characteristics of Zirconia and Modified Zirconia: Performance of CO Hydrogenation

Palladium-catalyzed alkoxycarbonylation of allyl bromide to unsaturated esters in supercritical carbon dioxide (sc-CO₂) was performed and compared with alkoxycarbonylation in organic solvents in this paper. Effects of the catalytic precursor, triphenyl phosphine ligand, base, pressure, and reaction temperature on the reaction yield and selectivity were mainly discussed. The results showed that sc-CO₂ was a favorable reaction medium for the reaction under lower CO pressure. Small changes, both in the CO₂ pressure as well as the amount of cosolvent ethanol, can cause drastic changes in both the reaction yield and selectivity. Moreover, FeCl₂ was found to have a promoting effect as cocatalyst on the reaction. The synergic effect of cosolvent ethanol with FeCl₂ can lead to an even better result than that in organic solvents.     

利用Ca2+掺杂增强钙钛矿型LaFeO3的红外发射率

采用固相反应法,在空气气氛中制备了纯LaFeO3和Ca2+掺杂的LaFeO3,对其在近红外波段的发射率进行了研究和比较. 结果表明,掺杂10mol% Ca2+的La0.9Ca0.1FeO3在3?5 ?m波段的红外发射率达0.92,比纯LaFeO3提高了119%. 原因为Ca2+掺杂进入LaFeO3的晶格后,在其半导体带隙中引入Fe4+杂质能级,形成了跃迁激活能仅需0.1 eV的Fe3+?Fe4+小极化子吸收带,增强了LaFeO3的红外辐射性能.     

彩印纸板醇溶快干上光涂料的研制

以氨基树脂585-1、0.5s稍化棉为成膜物质、无水乙醇作为稀释剂,加入助溶剂和催干剂,得到一种醇溶性纸张上光涂料.通过正交试验,讨论了树脂、硝化棉、助溶剂、催干剂等组分及用量对涂料性能的影响.结果表明,当树脂、硝化棉、助溶剂和催干剂质量分别为4、10、21和1g时,上光涂料的干燥速率最大,涂膜综合性能良好.     

载铜树脂处理高含盐氨氮废水的性能

针对高含盐氨氮废水,选择具有不同功能基团的树脂为载体,进行负载Cu2+改性制得载铜树脂并对其处理高含盐氨氮废水的性能进行研究。在筛选出最佳载铜树脂的基础上,研究pH及Na+浓度、树脂投加量、反应时间对载铜树脂处理高含盐氨氮废水效果的影响,通过对吸附氨氮前后的载铜树脂进行SEM和EDS表征分析并构建吸附动力学模型以进一步探究配位吸附的过程。结果表明,Cu2+可与螯合树脂D751稳定结合且在宽pH值下均表现出耐盐性和良好的氨氮吸附效果;在室温(25℃)、pH=11及Na+浓度4 g/L、树脂投加量8 g/L、反应时间60 min的条件下,D751载铜树脂对氨氮的去除率为34.8%。D751载铜树脂吸附氨氮后其表面出现明显的晶状结构物质,该物质可能为铜氨络合物。D751载铜树脂对高含盐氨氮的吸附符合准二级动力学模型。     

镧和钴掺杂纳米TiO2的溶胶-凝胶法制备及其光催化性能

采用溶胶-凝胶法,制备了TiO2、Co^2＋／TiO2、La^3＋／TiO2＋,Co^2＋,La^3＋／TiO2光催化剂。通过考察掺杂离子的种类和用量对所得催化剂用于紫外光催化降解亚甲基蓝性能的影响,得出La^3＋／TiO2中La^3＋的适宜掺杂量为1.0％,Co^2＋,La^3＋／TiO2中,当La^3＋的掺杂量为1.0％时,Co^2＋的适宜掺杂量为0.2％,相应的脱色效率为99.83％、98.79％。当掺杂量适当时,四种催化剂用于紫外光催化降解亚甲基蓝的活性次序为：La^3＋／TiO2〉Co^2＋,La^3＋／TiO2〉TiO2〉Co^2＋／Ti02o XRD分析结果表明,所得光催化剂均为纳米粒子。