土壤中拟除虫菊酯类残留农药的气相色谱测定方法研究

建立了土壤中氯氰菊酯、氰戊菊酯和溴氰菊酯的提取、净化以及毛细管气相色谱的测定方法。运用石油醚-丙酮（P／P，2：1）混合溶剂提取，用氟罗里硅土进行层析净化，60ml石油醚／乙酸乙酯（V／V，9：1）进行洗脱，电子捕获-气相色谱测定，单点外标法定量。实验表明：土样中添加0．08mgkg^-1的氯氰菊酯、氰戊菊酯和溴氰菊酯3种农药混标时，方法回收率为89．67％～90．62％，添加0．40mgkg^-1时．方法回收率为91、07％～93．02％；操作中相对标准偏差（RSD）为2．02％～3．70％，最小检出量可达1．00pg。在检测色谱精密度实验中，5次测定3种农药混标，相对标准偏差（RSD）为1．37％～2．88％。实验表明，该法具有灵敏度高、操作简便、净化效果好、重现性好等特点。     

参术补钙颗粒的质量标准研究

建立了参术补钙颗粒的质量标准。采用薄层鉴别方法鉴别甘草、党参、白术;采用原子吸收分光光法测定参术补钙颗粒中钙的含量; HPLC法测定参术补钙颗粒中维生素D_3的含量。结果表明以三氯甲烷∶乙酸乙酯∶甲醇∶水(15∶40∶22∶10)10℃以下放置的下层溶液作为展开剂,喷10%硫酸乙醇,加热5至10 min,置紫外365 nm下检视可鉴别出甘草;以甲苯∶乙酸乙酯∶甲酸(20∶8∶0.5)为展开剂中展开,喷10%硫酸乙醇,105℃加热可鉴别出党参;以三氯甲烷∶丙酮(19∶1)作为展开剂,置紫外365 nm下检视可鉴别出白术;钙在0～18μg/mL范围内线性关系良好,RSD为1.75%,参术补钙颗粒中所含钙的含量定为8.76 mg/g;维生素D_3.在125～100μg/mL范围内线性关系良好,平均回收率为94.83%,RSD为2.77%,参术补钙颗粒中所含维生素D_3的含量定为0.0248μg/g。该方法定性定量方法简便、准确、灵敏度高、重复性好,可用于参术补钙颗粒的质量控制。     

超高效液相色谱-质谱法测定豆芽中6-苄基腺嘌呤的方法研究

[目的]建立超高效液相色谱-质谱联用法(UPLC-MS/MS)测定豆芽中6-苄基腺嘌呤(6-BA)的方法。[方法]豆芽样品经过酸化甲醇提取,高速离心沉淀分离后,采用超高效液相色谱柱WATERS ACQUITY C18(50 mm×2.1 mm,1.7μm)分离,乙腈和0.1%甲酸水溶液进行梯度洗脱。[结果]6-BA在1.0~200.0 ng/ml范围内,线性关系良好,回归系数R~2为0.998 4,回收率达到85.3%~93.0%,精密度达到1.39%~2.75%。[结论]该方法稳定,操作简便、快速,提取效率高,重现性好,对豆芽样品中6-BA的检测提供了有力的技术支持,有很高的实用价值。     

低压离子色谱综述

低压离子色谱仪器简单、易使用和维护,分析准确率、精密度、灵敏度、检测限及速度都可与离子色谱相媲美。介绍了低压离子色谱的诞生、工作流程、色谱柱的型号及适用分离离子、洗脱条件、检测器以及在环境样品分析、石油化工工业分析、皮革工业分析、稀土样品分析、食品分析、生化样品分析中的应用。     

电感耦合等离子体质谱法和原子荧光法测定植物性食品中硒含量的对比分析

[目的]运用电感耦合等离子体质谱法和原子荧光法对植物性食品中的硒含量进行测定.[方法]试验采用密闭高压消解技术和湿法消解对样品进行前处理,分别采用电感耦合等离子体质谱法和原子荧光法测定植物性食品中痕量硒的含量,并对2种方法进行了对比分析.[结果]研究表明,2种方法的线性回归方程的相关系数均大于0.999,其方法检出限分别为0.01、0.04 ~L,加标回收率在95.6％～103.0％,相对标准偏差均小于5％,2种方法均具有良好的准确度和灵敏度.[结论]试验表明,电感耦合等离子体质谱法简单快速、线性范围宽,更加省时,效率更高.     

Litterfall,decomposition, and nitrogen release in two age groups of trees in Casuarina equisetifolia plantations in the dry tropical Vindhyan plateau,India

Litterfall, decomposition, and N release in 5-year-old and 8-year-old plantations of Casuarina equisetifolia (Forst.) in the dry tropical region of the Vindhyan plateau were studied during 1989–1990. Maximum litterfall occurred in May. The total litterfall ranged from 7.2 to 9.9t ha^-1 year^-1 in the 5-year-old stand and from 11.3 to 12.7t ha^-1 year^-1 in the 8-year-old stand over the 2-year period. Photosynthetic branchlets contributed 87–95% to the total litter. The relative decomposition rates of litter components of the ash-free mass were highest in the rainy months (4.7 to 9.9mg g^-1 day^-1) followed by winter (2.8 to 3.6 mg g^-1 day^-1) and lowest in the summer months (1.7 to 3.0 mg g^-1 day^-1). Similar patterns were observed for N release. The annual decay constant was highest for cone litter and lowest for photosynthetic branchlets. During decomposition, the photosynthetic branchlets showed N immobilization in November and April, the twig litter in March, and the roots in January and February. N release per unit area (g m^-2) was maximum from the photosynthetic branchlets (5.3–6.3) followed by cones (4.4) > roots (3.4) > twigs (2.6–3.2). The combination of the litter C:N ratio, moisture, and temperature with the relative decomposition rate in a multiple regression analysis explained 66–84% of the variability in mass loss and 58–66% of the variability in N release.     

LXH-CY型质量流量计的研制

介绍了一种主要用于油田单井出油初步计量的三相质量流量计，包括其测量原理、结构、功能特点和技术指标等。     

油茶炭疽病菌毒素对不同抗性油茶物种的生理生化效应

根据植物感病过程中特异性毒素对寄主的作用原理,利用油茶炭疽病菌产生的外毒素,对不同抗性油茶物种的叶进行处理,观察毒素对细胞质膜透性的影响,测定与抗性有关的重要生理生化指标效应。高抗攸县油茶、中抗小叶油茶和高感普通油茶叶组织的电导率及各项生理生化指标的变化趋势是与林间鉴定的三种不同油茶物种抗炭疽病能力一致;并证实了油茶炭疽病菌毒素是普通油茶的专一性毒素。     

Alteration of serum free fatty acids during the carbon tetrachloride-induced fatty liver in rats

AIM: To investigate the alteration of serum free fatty acids in the carbon tetrachloride-induced fatty liver. METHODS: Drug-induced fatty liver rat models were built by injection 40% CCl₄. Serum free fatty acids were analyzed by gas chromatography. RESULTS: In the composition of serun free fatty acids, polyunsaturated fatty acids[oleic acid C18:1,(28.672±7.332/mg·L^-1 vs 41.373±2.180/mg·L^-1),linoleic acid C18:2(16.739±0.871/mg·L^-1 vs 24.959±5.325/mg·L^-1),arachidonic acid C20:4(6.105±2.656/mg·L^-1 vs 9.802±0.779/mg·L^-1),P<0 05], were decreased significantly, but saturated fatty acids [lauric acid C12：0(3.368±0.330/mg·L^-1 vs 2.742 0.351/mg·L^-1),myrist ic acid C14:0(27.136 3.158/mg·L^-1 vs 16.152±0.638/mg·L^-1),palmitic acid C16:0(51.731±9.561/mg·L^-1 vs 34.522±1.401/mg·L^-1),P<0 05] increased. CONCLUSION: Serum polyunsaturated fatty acids were decreased and saturated fatty acids increased in the drug-induced fatty liver.     

散堆木片热物性参数的测定与研究

本实验利用ＤＲＭ－１型导热系数测试仪，测定和研究了杨木、桦木、椴木、榆木四种木片在不同含水率时的导热系数、导温系数和比热容（料床绝干密度保持不变）。实验表明，当含水率变化范围为１０％～９０％时，木片的导热系数随含水率的降低而明显减小，数量级为０．１７～０．２８Ｗ／（ｍ·Ｋ）；木片的导温系数随含水率的降低而有所增大，数量级为０．００１２～０．００３４ｍ￣２／ｈ；木片的比热容随含水率的降低而明显减小，数量级为０．４～０．７ｋＪ／（ｋｇ·Ｋ）。树种均为阔叶树材，树种对热物性参数几乎没有影响。