皮胶原纤维固载Zr(IV)对水体中苯羧酸的吸附特性

制备皮胶原纤维固载Zr(IV)吸附剂(ZLCF),并考察ZLCF对水体中苯甲酸(BA)、邻苯二甲酸(o-PA)、对苯二甲酸(p-PA)和间苯二甲酸(m-PA)的吸附特性.研究表明:这4种苯羧酸的吸附平衡同时符合Langmuir和Freundlich方程,但随着它们的羧基数量和位置的不同,其吸附容量也随之变化.总体看,ZLCF对所研究的苯羧酸均具有较大的吸附容量.当苯羧酸溶液(10 m1)的初始浓度为6 mmol/L、吸附温度为293 K时,ZLCF(0.05 g)对BA、o-PA、m-PA和p-PA的吸附容量分别达0.4616、0.5892、0.4912和0.3138 mmol/g.吸附动力学研究表明:BA的吸附符合拟一级速率方程,边界层扩散为主控步骤;而o一PA、m-PA和p-PA的吸附符合拟二级速率方程,化学吸附为主控步骤.     

杂多酸(盐)催化新型香料草莓酯的合成

采用硅钨酸铝作催化剂 ,以乙酰乙酸乙酯和 1 ,2 丙二醇为原料合成草莓酯。优化的反应条件为 :0 2mol乙酰乙酸乙酯 ,0 2mol1 ,2 丙二醇 ,40ml环己烷 ,0 3 g硅钨酸铝 ,反应 3 5h ,草莓酯收率达 81 6%。产物经理化检验和红外光谱确证     

Coupling System for Food Wastes Anaerobic Digestion and Polyhydroxyalkanoates Production with Ralstonia eutropha

A new technology was developed to couple the anaerobic digestion of food wastes with production of polyhydroxyalkanoates (PHAs). Acetic, propionic, butyric and lactic acids were produced during food wastes anaerobic digestion and their concentrations reached 5.5, 1.8, 27.4 and 32.7 g/L, respectively under appropriate digestion conditions. The fermentative acids were transferred through a dialysis membrane to an air-lift reactor for PHA synthesis by Ralstonia eutropha. Dry cell concentration and PHA content reached 22.7 g/L and 72.6%, respectively. The obtained PHA was a copolymer of b-hydroxybutyrate (HB) and b-hydroxyvalerate (HV) with 2.8% (mole ratio) of HV units in polymer.     

Characterization of chemicals mediating ovipositional host-plant finding byAmyelois transitella females

Ovipositional host-finding in the navel orangeworm,Amyelois transitella (Walker), is brought about by an in-flight response to host odors. Wind-tunnel studies of the response of gravid females to almonds showed that this response is mediated primarily by long-chain fatty acids, particularly oleic acid and linoleic acid. Evidence for the behavioral activity of fatty acids is based on the fact that: (1) behavioral activity of almond oil was concentrated in a single liquid chromatographic fraction whose composition was predominantly long-chain fatty acids, (2) behavioral activity was lost when either almond oil or the active fraction of that oil was treated with diazomethane, (3) full activity was elicited by a selective extraction of free fatty acids from crude almond oil, and (4) upwind response by females was elicited by a blend of synthetic oleic and linoleic acids, albeit at a level less than that elicited by almond oil. Five fatty acids identified from the almond oil were: myristic acid (1%), palmitic acid (16%), stearic acid (3%), oleic acid (58%), and linoleic (22%). Attraction to various combinations of synthetic acids was observed only when oleic acid was present, and oleic acid elicited upwind flights to the source when presented alone; however, short-range responses were enhanced by the addition of linoleic acid, which elicited no long-range orientation by itself. Despite significant levels of attraction to synthetic blends, the percentage of females flying to the source was lower than that flying to acidulated almond oil, the best natural attractant tested. Thus, although longrange response may be mediated primarily by a blend of oleic and linoleic acids, additional and as yet unidentified components must also play an important role. Long-range chemically modulated host finding in this and other generalist plant feeders is discussed with respect to current models of the evolution of host finding, and it is argued that suggestions that long-range host finding should be correlated with narrowness of host utilization are logically flawed and are not supported by our current understanding of specific examples of host finding.     

In situ esterification of rice bran oil with methanol and ethanol

In situ esterifications of high-acidity rice bran oil with methanol and ethanol and with sulfuric acid as catalyst were investigated. In the esterification with methanol, all free fatty acids (FFA) dissolved in methanol were interesterified within 15 min, and it was possible to obtain nearly pure methyl esters. The amount of methyl esters obtained from a given rice bran was dependent on the FFA content of the rice bran oil. In the esterification with ethanol, it was not possible to obtain pure esters as in methanol esterification, because the solubilities of oil components in ethanol were much higher than those in methanol.     

Macromolecular recognition by cyclodextrins. Interaction of cyclodextrins with polymethacrylamides bearing hydrophobic amino acid residues

The interaction of cyclodextrins (CDs) with poly(N-methacryloyltryptophan) (pMTrp) and with poly(N-methacryloylphenylalanine) (pMPhe) was investigated as a simple model system of macromolecular recognition of proteins. The association constants (K) for the model compounds, sodium salts of tryptophan and phenylalanine, are not so different (i.e. 43 and 16 M⁻¹ for α-CD, 59 and 69 M⁻¹ for β-CD, and 12 and 3 M⁻¹ for γ-CD, respectively). On the other hand, there is a significant difference in the apparent K values for pMTrp and pMPhe (i.e. the K values for pMPhe are considerably smaller than ca. 10 M⁻¹, whereas those for pMTrp are 30, 83, and 11 M⁻¹ for α-, β-, and γ-CDs, respectively). These observations indicate that a subtle difference in polymer side chains can be critical in macromolecular recognition.     

A highly regioselective synthesis of δ-lactones from meadowfoam fatty acids

Meadowfoam fatty acids, when treated with mineral acid catalysts in the presence of polar nonparticipating solvents, undergo a facile ring closure to form δ-lactones. Perchloric and sulfuric acids catalyze the cyclization at concentrations of 0.6–13 mole equivalents, both neat and in the presence of solvent. Under constant acid concentrations, methylene chloride was found to increase the rate of reaction, the regioselectivity for the formation of δ-lactone, and the overall yield. In the absence of solvent, increased acid concentration improved the yield of lactone but reduced regioselectivity for the δ-isomer. Solvent polarity plays a significant role in the regioselectivity of the cyclization for δ-lactone, with solvents of higher dielectric strength providing larger δ/γ ratios (38:1) and higher yields up to 92%.     

Separation of crude palm oil components by semipreparative supercritical fluid chromatography

Successful separation of triglycerides, diglycerides, free fatty acids, carotenes, tocopherol, and tocotrienols from crude palm oil has been achieved by supercritical fluid chromatography (SFC) with a combination of a C18 and a silica gel column. The separation was carried out by the programmed extraction elution method. Free fatty acids were separated into five components by gas-liquid chromatography; tocopherol and tocotrienols were also separated into four components by SFC analysis, and the pure fractionated carotenes were obtained by preparative SFC. Thus, by using supercritical fluid chromatography, crude palm oil components can be separated and fractionated, based on differences in their functional groups.     

腐殖活性污泥生化特征及处理效能

为探讨腐殖活性污泥的生物化学特征及其作用机理,对腐殖生物填料进行扫描电镜和能谱(SEM-EDAX)测定,表明填料中主要组成元素为C、O、Si,同时含有少量Al、S、Fe. 腐殖活性污泥与普通活性污泥中若干特征菌群的对比分析表明,腐殖活性污泥中的一般细菌总量、硝酸菌、亚硝酸菌、脱氮菌及放线菌含量明显高于普通活性污泥;腐殖活性污泥中有机质的质量分数比普通活性污泥低,但腐殖酸及富里酸和胡敏酸质量分数明显高于普通活性污泥;腐殖活性污泥法运行的SBR反应器对CODCr、TP和TN的去除效果优于普通SBR反应器,分别高出4％、14％和10％．     

大鼠灌胃中国蜂胶醇提物后血浆中5种酚酸类成分的HPLC测定及其药代动力学

对大鼠灌胃蜂胶乙醇提取物（EEP）后,血浆中5种酚酸类成分的药代动力学特性进行研究.用HPLC-UV法测定血浆中咖啡酸、香豆酸、阿魏酸、异阿魏酸和3,4-二甲氧基肉桂酸的浓度.应用WinNonlin非典型房室模型计算软件计算相应的药代动力学参数.血浆中内源性物质和内标对酚酸类成分测定无干扰,回收率、准确度及日内、日间精密度均符合生物样品测定要求.结果表明,该方法简便、快速、重复性好,适用于咖啡酸等5种蜂胶中酚酸类成分的大鼠血药质量浓度测定及体内药动学研究.