酸催化下苯酚液化木材的制备与表征

在硫酸作用下用苯酚对人工林杨木和杉木进行液化,考察反应时间、反应温度等对液化反应的影响,并对液化产物进行表征分析.结果表明:1)在硫酸催化下,杨木和杉木被苯酚液化的历程相似,但残渣含量稍有不同.酸性催化剂不仅对纤维素和半纤维素起作用,对木质素也起作用.2)反应温度比反应时间对液化效率的影响大,二者均能影响液化产物的分子量和分子量分布.通常杉木液化产物的重均分子量高于杨木.3)液化过程中,木质素和半纤维素首先被液化,最后是纤维素.木材组分的分解、酚化和再缩聚反应主宰整个液化动力学过程及液化产物的结构特征.     

中国野漆树与日本野漆树油脂成分差异性分析

漆树科(Anacandiaceae)资源丰富,约60属600种.据不完全统计,我国现有漆树群体5亿多株,能结籽的有1亿多株.目前,漆树研究大多是以生产生漆的漆树类为对象,对野漆树(Toxicodendron succedaneum)研究较少,而漆蜡(油)用途广泛,在化妆品、防水剂、涂料、粘接剂、润滑剂、电子摄影调色剂、水果保鲜剂及蜡纺印花等轻化电子产业中有巨大的潜力(王成章,2001;唐丽等,2010).     

液液萃取气相色谱法测定地表水中多氯联苯

指出了多氯联苯是一种持久性环境污染物,地表水中 PCBs液液萃取气相色谱法分析技术具有相当的代表性,以EPA的标准分析方法为基础,结合多年实验经验,对此方法内容进行了详细描述并对部分内容进行了优化,旨在为该方法的转化研究提供一些参考。     

离子色谱-质谱联用法测定食品中溴酸盐

建立离子色谱-质谱（IC-MS）联用方法检测食品中溴酸盐。不同食品样品中的BrO3-离子经水提取,经过C18和Ag柱除杂质,再经离子色谱分离,最后在选择反应监测模式（SRM）下进行检测,外标法定量。 BrO3-质量浓度在0.1~100μg/L内具有良好的线性关系（R2=0.9999）,检出限为1.0μg/kg,定量限为4.0μg/kg。加标回收率为92.7%~104.2%,精密度RSD<5%,该方法的灵敏度、准确度和精密度均符合相关的技术要求,适用于食品中痕量BrO3-分析的要求。     

DETERMINATION OF METALLIC IRON IN HIGH TITANIUM SLAG BY HEADSPACE GAS CHROMATNGRALHY

The following details are discussed in the present paper, after high titanium slag and H3PO4 is put in the closed system,the .reaction takes place under controlled temperature conditions, and the gas produced is collected. The two phases of gas liquid attain kinetic equilibrium, ihe gas above the liquid is used to make GC analysis with the aid of chromatographic column of 5A molecular sieve, TCD and N2 30ml/min. Satisfactory quantitative results can be achieved with simple instruments and uncomplicated operation technique.     

The use of reversed-phase high performance liquid chromatography as an aid to the identification of European barley cultivars

Summary A reversed-phase high performance liquid chromatography (RP-HPLC) system was used to separate the storage proteins (hordeins) extracted from European barley cultivars. From a total of 38 barleys tested, 26 types of hordein patterns could be distinguished after RP-HPLC. This appears to be a marked improvement in resolution over that achieved in a similar survey of European barley cultivars using SDS polyacrylamide electrophoresis (32 hordein patterns resolved by SDS PAGE from a total of 160 spring and winter barleys tested).Different hordein patterns were resolved by RP-HPLC within each of two groups of barley previously classified by SDS PAGE as indistinguishable within groups (three distinct patterns identified in a total of five cultivars tested from group 1A and five patterns observed among eight cultivars from group 3B). Thus RP-HPLC achieves a higher resolution than undirectional electrophoresis and promises to be a valuable aid in the identification of European barley cultivars.     

印度Leh地区沙棘籽油中脂肪酸测定

本文分析了印度Leh地区沙棘籽油中脂肪酸各成分的含量,结果显示沙棘种子含油量为17.61%,籽油富含油酸(23.012%)和亚油酸(30.162%).     

Patterns and heritability of carboxylic acids and soluble sugars in fruits of apricot (Prunus armeniaca L.)

The investigation of acid and sugar content in an array of apricot cultivars and progenies indicates the existence of marked variability. Citric acid varied from 0.17 to 1.20% and malic acid from 0.21 to 1.51% on fresh weight. Fructose varied from 0.27 to 1.60%, glucose from 0.90 to 3.13% and sucrose from 1.92 to 6.92%. The estimate of heritability was high for total and main sugars, reaching over 0.50%. Acids generally showed low coefficients, although those for citric (0.27) and malic (0.36) were good. With the exception of one progeny, all genotype/year comparisons were not significant, showing constant patterns for acid and sugars over the years regardless of the variability in absolute values. This means that the patterns of each genotype are under genetic control. The wide range of diversity in acid and sugar content in apricot germplasm and the independent heritability for most of these compounds make it possible to breed and select cultivars with improved flavour on the basis of superior phenotypes.     

Tandem size exclusion chromatography-Polyacrylamide gel electrophoresis of humic acids

Humic acids (HAs) from four soils were fractionated by size exclusion chromatography (SEC) on Sephadex G-75. Three fractions were obtained in all humic acids, collected and assayed by Polyacrylamide gel electrophoresis (PAGE). The unfractionated HA from each soil was used as reference. Each chromatographic fraction formed one electrophoretic zone corresponding closely to one band of the reference sample with some admixture of the fractions preceding or following. The results indicate that fractionation of HAs by tandem SEC-PAGE can be successfully used for obtaining fractions of reduced polydispersity and different electrophoretic mobilities. Pyrolysis/methylation-gas chromatography-mass spectrometry of the full size preparations of HA and fractions with exactly defined molecular size and electrophoretic mobility showed a different distribution in humic components, mainly lipids, lignin derivatives and N-containing compounds.     

纸层析分离转氨作用产物方法的改进

本文介绍作者研制的一种用于纸层析分离转氨作用产物──氨基酸的展层剂,它含有乙醇、水和尿素（80：20：0．5）,与传统的展层剂苯酚和水相比,它具有价格便宜（节省经费217％）、安全无毒、操作方便等优点,是一种理想的展层剂。