笼形聚偕胺肟树脂的研究─—H_2PtCl_6在酸处理树脂上的吸附过程

H2PtCl6可被一系列的酸处理定形聚偕胺肟树脂所吸附，吸附容量的大小与处理树脂的质子酸的Pka值有关．认为是解高度低的酸所处理的树脂上的伯胺基成盐的机会较少，即树脂的吸附中心保留着较多的空穴，有利于H2PtCl6的接近而被吸附下来．吸附动力学的研究表明化学反应是吸附速度的控制因素。     

CARBONIZED FIBROUS RESIN AS A NEW SORBENT FOR SAMPLING POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) IN AMBIENT AIR

1. INTRODUCTION When investigating contaminated sites it is often essential to determine specific pollutants in a large number of ambient air samples. Amongst these sites, polycylic aromatic hydrocarbons (PAHs) are a major class of compounds that hav…     

螯合树脂交换——光度法测定氯化钠溶液中微量镁

研究了用螯合树脂交换分离富集氯化钠溶液中微量镁及吸光光度法测定镁含量的方法。回收率为９６．０－１０１．０％，在ＰＨ１０的硼砂－氢氧化钠介质中，镁含量在０－１２μｇ／２５ｍｌ范围内符合比耳定律。方法稳定性高、重现性好。     

Synthesis of Ultrafine SiC Powders from Carbon-Silica Hybridized Precursors with Carbothermic Reduction

Inorganic-organic hybrid gels were prepared by simultaneous condensation of the liquid mixture of ethyl silicate, ethyl borate and water soluble phenol resin with low molecular weight. The liquid mixtures were changed into lightly colored transparent gels after a catalyst addition and stirring. The obtained gels were crushed, dried and fired in controlled conditions to yield the inorganic precursors. Since the tailored inorganic precursors mainly consisted of SiO2 and carbon, silicon carbide was formed with the heat treatments in an Ar atmosphere beyond 1773 K with carbothermic reduction. The properties and morphology of the formed silicon carbide powders in terms of the starting precursor compositions and the conditions of the carbothermic reduction were investigated with SEM, XRD and TG-DTA analysis.     

Mechanistic study of thermal behavior and combustion performance of epoxy resins: I homopolymerized TGDDM

Tetraglycidyl 4,4′-diaminodiphenylmethane (TGDDM) undergoes homopolymerization on heating. Intramolecular reactions which compete with crosslinking favor the formation of cyclic structures with increasing thermal and fire resistance of the resin, whereas physical mechanical properties tend to decrease. The mechanism of thermal decomposition of TGDDM is studied by thermogravimetry, differential scanning calorimetry and thermal volatilization analysis with characterization of volatiles evolved and residue left. Thermal degradation of poly-(TGDDM) starts at 260°C with elimination of water from secondary alcoholic groups which is a typical pathway for epoxy resin degradation. Resulting unsaturations weaken bonds in the β-position and provoke the first chain breaking at allyl–amine and allyl–either bonds. With increasing temperature, saturated alkyl–ether bonds and alkyl carbon–carbon bonds are broken first, followed by the most stable alkyl–aryl bonds at T>365°C. The combustion performance of TGDDM is discussed on the basis of the thermal degradation behavior.     

A straightforward preparation of a polystyrene thiol resin

A mild and efficient two-step synthesis of a polystyrene thiol resin is reported. Firstly, a polystyrene resin was reacted with an activated sulfoxide to afford the resin bound bis-(2-methoxy-carbonylethyl)-sulfonium trifluoromethanesulfonate. Smooth β-elimination based dealkylations afforded the polystyrene thiol resin with good and controlled loading. Its reactivity was assessed through a derivatisation step.     

双烯合成反应与气相色谱法联合测定油品中共轭二烯烃含量的研究 Ⅱ.短毛细管柱气相色谱法

在填充柱气相色谱法的基础上，使用１２ｍ×０．２２ｍｍｉ．ｄ．的ＳＥ－３０短毛细管柱（ＷＣＯＴ），分析了乙烯生产副产物——未加氢裂解汽油（５５℃～２２０℃馏分）中共轭二烯烃的含量，分析一次需２２ｍｉｎ，内标物正十六烷得到了很好的分离。     

配糖蛋白B—阳离子丙烯酸树脂微胶囊的性能研究

本文研究了配糖蛋白B-阳离子丙烯酸树脂微胶囊的形态、粒径及粒径分布,并在模拟胃液的酸性缓冲液中进行了微胶囊的溶解释放试验。结果表明该微胶囊能溶于人体的胃液中,可配制适合儿童口服的混悬剂。     

Functionalization of chitosan with 3-nitro-4-amino benzoic acid moiety and its application to the collection/concentration of molybdenum in environmental water samples

A chitosan resin functionalized with 3-nitro-4-amino benzoic acid moiety (CCTS-NABA resin) was newly synthesized for the collection/concentration of trace molybdenum by using cross-linked chitosan (CCTS) as base material. The carboxyl group of the moiety was chemically attached to amino group of cross-linked chitosan through amide bond formation. The adsorption behavior of molybdenum as well as other 60 elements on the resin was examined by passing the sample solutions through a mini-column packed with the resin. After the elution of the elements collected on the resin with 1 M HNO₃, the eluates were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) and atomic emission spectrometry (ICP-AES).

The CCTS-NABA resin can adsorb several metal ions, such as vanadium, gallium, arsenic, selenium, silver, bismuth, thorium, tungsten, tin, tellurium, copper, and molybdenum at appropriate pHs. Among these metal ions, only molybdenum could be adsorbed almost completely on the resin at acidic regions. An excellent selectivity toward molybdenum could be obtained at pH 3–4. The adsorption capacity of CCTS-NABA resin for Mo(VI) was 380 mg g⁻¹ resin. Through the column pretreatment, alkali and alkaline earth metals in river water and seawater samples were successfully removed.

The CCTS-NABA resin was applied to the adsorption/collection of molybdenum in river water and seawater samples. The concentrations of molybdenum in river water samples were found in the range of 0.84 and 0.95 ppb (ng g⁻¹), whereas molybdenum in seawater was about 9 ppb. The validation of the proposed method was carried out by determining molybdenum in the certified reference materials of SLRS-4, CASS-4, and NASS-5 after passing through the CCTS-NABA resin; the results showed good agreement with the certified values.     

弱酸树脂D113对S-腺苷-L-蛋氨酸的交换行为及分离应用研究

考察了S-腺苷-L-蛋氨酸 (S-adenosyl-L-methionine, SAM) 在弱酸树脂争光D113上的静态吸附及分离行为,利用Langmuir等温式对平衡等温线进行了拟合,实验表明,随着pH的提高,平衡交换量增加,提高温度和SAM的初始浓度在一定程度上能促进内扩散过程,利用D113树脂在f 1.7×30.0cm小型柱上从酵母提取液中分离SAM的得率为90%以上,纯度达87%以上。