凝结水精处理阳树脂硫酸根溶出特性研究

电站给水系统中存在微量的SO42-就会对金属材料造成严重腐蚀。针对目前凝结水精处理系统投运后导致核电站蒸汽发生器或炉水中SO42-含量升高的问题,采用动态循环溶出和静态浸泡的方法对几种凝结水精处理常用阳树脂的SO42-溶出行为进行了研究。结果表明,不同树脂的SO42-溶出行为有较大差异,SO42-含量在短时间内随时间增长呈上升趋势,新树脂溶出SO42-的量比旧树脂大得多。通过对溶出液进行高温和氧化处理,发现溶出物中还含有一些有机磺酸盐,它们在高温或氧化条件下会分解产生SO42-和酸性物质。     

对凝结水处理用离子交换树脂的有机溶出物的研究

对具有代表性的凝结水处理阳、阴各十种离子交换树脂有机溶出物的量及溶出规律进行了测定,同时就阳树脂溶出物对阴离子交换树脂的污染,以及通过再生、碱性盐水复苏对此污染的去除,也作了试验测定。     

离子交换树脂在高参数水汽系统中的分解特性研究

通过高压釜模拟高温高压的水汽环境,研究了离子交换树脂在温度为230℃和300℃下的分解特性,全面检测了离子交换树脂的各种分解产物和树脂分解前后的结构变化,结合树脂的化学结构,分析了离子交换树脂的分解机理,并通过高压釜挂片试验,探究了离子交换树脂的分解产物对TA16合金的影响。试验结果表明,离子交换树脂的分解包括具有离子交换能力的活性基团的脱离和树脂骨架的分解,H型阳树脂分解产生了H2SO4,Na型阳树脂分解生成了NaHSO4,OH型阴树脂分解生成了三甲胺,Cl型阴树脂分解产生氯化三甲铵,4种树脂分解都有苯及苯的同系物生成,且分解产物对TA16合金没有明显的腐蚀。     

大孔阳离子交换树脂对井冈霉素的吸附研究

比较了5种大孔树脂与常用的001×4凝胶树脂对井冈霉素的静态和动态吸附的性能实验,并选择了其中几种有代表性的树脂,研究其对井冈霉素的吸附特性及其机理.采用正交试验筛选出具有较大吸附量的大孔强酸性阳离子树脂HD-8,并对其工艺条件进行了优化,其较优吸附能力为15.34mg/ml树脂h;同时考察了HD-8树脂的解吸行为,发现用1mol/L的氨水:80%乙醇=1:1洗脱率为98.8%,洗脱效果明显.     

采用吸附树脂Amberlite XAD-4从水溶液中富集痕量元素

本文采用短吸附柱(10×60mm,充填高度24mm)研究了非离子性吸附树脂AmberliteXAD-4从水溶液中对16种金属元素的氢氧化物,二硫代氨基甲酸衍生物的配合物和二甲酚橙配合物的吸附行为。难溶金属化合物在树脂上的吸附率与溶液pH值的关系与采用活性碳作吸附剂的情况十分相似。而含有亲水基团的二甲酚橙螯合物不被树脂吸附。对吸附于树脂上的痕量元素的洗脱以及采用火焰原子吸收光谱法测定丙酮富集液中的金属元素问题也进行了讨论。     

离子交换树脂去除氯化铝溶液中铁和镓工艺研究

本文采用离子交换树脂去除“一步酸溶法”提取氧化铝工艺中氯化铝溶出液的铁和镓杂质,考察了四种离子交换树脂去除杂质的能力。试验表明,D201MBP型离子交换树脂的杂质吸附率最高,最佳反应条件为树脂和溶出液质量比为1:10,反应温度70℃,反应时间30min,溶出液浓度1～1.2(原溶出液浓度设为1),Fe和Ga的吸附率可达93%和98%,且Al的损失率仅为3.9%。在室温下,用0.5%盐酸溶液洗脱饱和树脂,可达到良好的再生效果。     

医药和食品级高分子材料溶出物试验模拟试剂选择原则及选择方案

高分子材料制品与医药和食品工业的液体制品在生产和储运过程中长时间接触后的材料溶出程度和溶出物质的安全性越来越受到国内外学者的关注。对于溶出物试验而言,如何根据实际液体制品的成分确定合适的模拟试剂体系显得十分重要。本文从溶出物试验的试剂选择原则和溶剂分类理论角度入手,提出了基于两种不同理论依据的模拟试剂选择方案,为之后研究人员在撰写和评估溶出物试验方案时提供了模拟试剂体系的设计思路和参考意见。     

新型阻溶促溶酚树脂用于热敏CTP版的性能研究

使酚树脂与乙烯基醚发生反应,合成出一种新型醚化物,作为新型阻溶促溶剂.将它与产酸剂、背景染料、红外染料、成膜树脂、其它助剂及有机溶剂作为热敏CTP组合物.研究了该热敏CTP组合物的化学性能和热敏成像性能,发现在热敏CTP组合物中适量的新型阻溶促溶剂能够使热敏CTP版的热敏性、显影性、抗碱性及耐异丙醇性都得到了较大的改善.     

先锋褐煤可溶有机质中含氮化合物的组成和结构特征（英文）

先锋褐煤在高压釜中用等体积的甲醇/甲苯溶剂300℃下热溶得到热溶物和热溶残渣,利用X射线光电子能谱(XPS)分析了先锋褐煤及其热溶残渣中氮的形态,利用气相色谱/质谱(GC/MS)和电喷雾傅里叶变换-离子回旋共振质谱(ESI FT-ICR MS)分析了热溶物中含氮化合物的组成和结构特征。研究表明,先锋褐煤中氮形态含量顺序为季氮吡啶氮吡咯氮,而季氮在热溶过程中更易溶出。GC/MS共检测出热溶物中20种含氮化合物,并且大部分为胺类化合物。ESI FT-ICR MS检测出热溶物中300多种含氮化合物,大部分含氮化合物含一个或三个氮原子。含一个氮原子的含氮化合物主要以N_1O_1、N_1O_2和N_1O_xS_(1-2)类化合物为主,而含三个氮原子的含氮化合物主要以N_3O_xS_(1-2)(x=1-12)类化合物为主。含一个氮原子的含氮化合物的等效双键数和碳数随氧原子数增加而增加。     

盐酸酸洗对油页岩小分子溶出行为的影响

以广东茂名和辽宁抚顺油页岩为样品,对其进行盐酸酸洗,利用两种溶剂二氯甲烷和四氢呋喃对酸洗前后的油页岩进行索氏萃取,并利用GC/MS对萃取液进行分析,得出两种溶剂在酸洗前后萃取到的物质种类。研究油页岩在有机溶剂萃取条件下,小分子化合物的溶出规律。结果表明,酸洗更有利于油页岩中的小分子溶出,可以提高萃取率。酸洗对于萃取物组分中的烷烃化合物组分影响较小而对含氧小分子化合物组分影响相对较大。对比同一样品酸洗前后的萃取液,一些重复出现的物质的相对含量或检出物的个数发生了变化。二氯甲烷的溶出物主要是烷烃,四氢呋喃的溶出物主要是含氧小分子化合物。     

胺基化树脂负载Pd(0)对Heck反应催化性能的研究

将氯球用胺化剂、乙二胺、胍进行胺化后负载氯化钯, 在乙醇溶液中用硼氢化钾还原, 制备了含胺功能基树脂负载钯(0)的催化剂; 研究了催化剂对含各种取代基碘代苯与丙烯酸的Heck芳基化反应催化性能. 结果表明, 该类催化剂具有良好的催化活性和重复使用性能, 其中用乙二胺功能化树脂负载的Pd(0)催化剂在90 ℃重复使用17次时能保持良好的催化活性. 催化剂反应前后的SEM形貌图和过滤液的活性试验表明催化剂活性组分Pd(0)在反应中有沥取(leaching)现象.     

Particleboards from Acetylated Wood Flakes

Particleboards from acetylated wood flakes with various resins were pressed and compared with untreated control boards with respect to their weathering resistance and mechanical strength. The industrially used melamine, urea, and phenol resins showed a poor adhesion behavior to the acetylated flakes resulting in a high decrease of the mechanical strength of the particleboards. A novel type of apolar resin based on methylmelamines was developed and characterized. Using this resin particleboards with good mechanical strength and weathering stability could be produced.     

Particleboards from Acetylated Wood Flakes

Summary. Particleboards from acetylated wood flakes with various resins were pressed and compared with untreated control boards with respect to their weathering resistance and mechanical strength. The industrially used melamine, urea, and phenol resins showed a poor adhesion behavior to the acetylated flakes resulting in a high decrease of the mechanical strength of the particleboards. A novel type of apolar resin based on methylmelamines was developed and characterized. Using this resin particleboards with good mechanical strength and weathering stability could be produced.     

The immobilisation of anion exchange resins in polymer modified cements

Organic anion exchange resins, loaded with⁹⁹Tc pertechnate were incorporated into polymer modified cements and BFS/OPC(9∶1) cements. The composites formed were tested for initial compressive strenghts, underwater and radiation stabilities and leach rates. IAEA standard leach testing was with simulated sea and ground waters. Ground water leaching was also carried out on composites subjected to 1.1 MGy (γ). Polymer modified composites performed better than the BFS/OPC mix under all the conditions studied and, in most cases, were able to encapsulate high resin loading.     

Comparison of chromatographic ion-exchange resins. I. Strong anion-exchange resins

A comparative study has been undertaken on various strong anion-exchangers to investigate the pH dependence, titration curves, efficiency, binding strength, and dynamic capacity of the chromatographic resins. The resins tested included: Macro-Prep 25Q, TSK-Gel Q-5PW-HR, Poros QE/M, Q Sepharose FF, Q HyperD 20, Q Zirconia, Source 30Q, Fractogel EMD TMAE 650s, and Express-Ion Q. Testing was performed with five different proteins: Anti-FVII Mab (IgG), aprotinin, BSA, lipolase, and myoglobin. The dependence of pH on retention varies from generally low to very high for proteins with low pI. No direct link between pH dependence on retention and titration curves of the different resins was observed. Efficiency results show the expected trend of lower dependence of the plate height with increasing flow-rate of resins for medium and high pressure operation compared to the soft resins. Binding to the anion-exchange resins as a function of ionic strength may vary depending on the specific protein. Generally, binding and elution at a high salt concentration may be performed with Poros QE/M or Macro-Prep 25Q, while binding and elution at low salt concentration may be done with TSK-Gel Q-5PW. Dynamic capacities are strongly dependent on the specific protein employed and for some resins dependent on the flow-rate. A general good agreement was obtained between this study and data obtained by suppliers for the dynamic capacity. The results of this study may be used for selection of resins for testing in process development, however, the data does not tell anything about specific selectivity differences or resolution between a target protein and a given impurity. None of the resins studied here should be regarded as good or bad, but more or less suitable for a specific purpose, and only testing for the specific application will determine which one is the optimal resin.     

Behavior of human serum albumin on strong cation exchange resins: I. Experimental analysis

Experiments with human serum albumin on the strong cation exchange resin Fractogel EMD SE Hicap (M) were carried out. Even though human serum albumin was used at high purity, two peaks in gradient elution experiments occurred. The obtained data can be explained by considering that human serum albumin binds to Fractogel EMD SE Hicap (M) in two different binding conformations: the protein adsorbs instantaneously in the first conformation and then changes into the second one with a kinetic limitation. The two-peak behavior of human serum albumin was analyzed in detail, especially at various gradient lengths, concentrations and temperatures. Breakthrough curves were performed at four modifier concentrations and three velocities. The characteristic adsorption behavior, found for gradient experiments, was confirmed by the breakthrough curves. The two-peak elution pattern of human serum albumin was also found for other strong cation exchange resins, but not for weak cation exchange resins. It is concluded that the described behavior is peculiar for the interaction of human serum albumin with the strong cation exchange ligand of the resin.     

Protein adsorption and transport in dextran-modified ion-exchange media. I: Adsorption

Adsorption behavior is compared on a traditional agarose-based ion-exchange resin and on two dextran-modified resins, using three proteins to examine the effect of protein size. The latter resins typically exhibit higher static capacities at low ionic strengths and electron microscopy provides direct visual evidence supporting the view that the higher static capacities are due to the larger available binding volume afforded by the dextran. However, isocratic retention experiments reveal that the larger proteins can be almost completely excluded from the dextran layer at high ionic strengths, potentially leading to significant losses in static capacity at relevant column loading conditions. Knowledge of resin and protein properties is used to estimate physical limits on the static capacities of the resins in order to provide a meaningful interpretation of the observed static capacities. Results of such estimates are consistent with the expectation that available surface area is limiting for traditional resins. In dextran-modified media, however, the volume of the dextran layer appears to limit adsorption when the protein charge is low relative to the resin charge, but the protein–resin electroneutrality may be limiting when the protein charge is relatively high. Such analyses may prove useful for semiquantitative prediction of maximum static capacities and selection of operating conditions when combined with protein transport information.     

Multivariate Screening Analysis of Water-in-Oil Emulsions in High External Electric Fields as Studied by Means of Dielectric Time Domain Spectroscopy

The effect of crude oil resins with various polar characters on the stability of w/o model emulsions containing asphaltenes is investigated using a mixture design. The resins were extracted using an adsorption-desorption technique. One asphaltene fraction and four different resin fractions from one European crude oil were used. The stabilities are measured using time-domain dielectric spectroscopy in high external electric field. It is found that resins with different polar character have different effects on the emulsion stability. At asphaltene/resin ratios of 1 and 5 : 3 the resins in some cases lead to an emulsion stability higher than that of a similar emulsion stabilized by asphaltenes only, while at low asphaltene/resin ratios ( approximately 1 : 3) the emulsion stability is reduced by the resins. The effect on emulsion stability of combining two different resin fractions depended on the resin types combined as well as the relative amount of resins and asphaltenes. Also, an increase in the stability of some of the emulsions containing resins and asphaltenes for a period of 50-300 min after the emulsification was observed. This time-dependence of emulsion stability is attributed to the mobility of resins at the oil-water interface and the slow buildup of a stabilizing interfacial film consisting of resins and asphaltenes. Copyright 2000 Academic Press.     

Bioinspired Design Provides High‐Strength Benzoxazine Structural Adhesives

A synthetic strategy to incorporate catechol functional groups into benzoxazine thermoset monomers was developed, leading to a family of bioinspired small‐molecule resins and main‐chain polybenzoxazines derived from biologically available phenols. Lap‐shear adhesive testing revealed a polybenzoxazine derivative with greater than 5 times improved shear strength on aluminum substrates compared to a widely studied commercial benzoxazine resin. Derivative synthesis identified the catechol moiety as an important design feature in the adhesive performance and curing behavior of this bioinspired thermoset. Favorable mechanical properties comparable to commercial resin were maintained, and glass transition temperature and char yield under nitrogen were improved. Blending of monomers with bioinspired main‐chain polybenzoxazine derivatives provided formulations with enhanced shear adhesive strengths up to 16 MPa, while alloying with commercial core–shell particle‐toughened epoxy resins led to shear strengths exceeding 20 MPa. These results highlight the utility of bioinspired design and the use of biomolecules in the preparation of high‐performance thermoset resins and adhesives with potential utility in transportation and aerospace industries and applications in advanced composites synthesis.