高效液相色谱法同时测定药物中异烟肼、异烟酸、异烟酰胺和4－氰基吡啶

建立了以甲醇醋酸钠溶液（体积比为１２∶８８）为流动相，同时分离和测定制药生产流程中的异烟肼、异烟酰胺、异烟酸和４氰基吡啶的高效液相色谱法。方法各组分的质量浓度线性范围和检出限分别为：异烟肼０１１～１０６０ｍｇ／Ｌ和０１１ｍｇ／Ｌ；异烟酰胺和异烟酸００７～１０２０ｍｇ／Ｌ和００７ｍｇ／Ｌ；４氰基吡啶０２６～１０２３ｍｇ／Ｌ和０２６ｍｇ／Ｌ。对高含量组分测定７次，其ＲＳＤ＜１％，微量组分的ＲＳＤ＜１０％。     

高效液相色谱法同时测定药物中异烟肼,异烟酸,异烟酰胺和4…

建立了以甲醇－酸醋酸钠溶液（体积比为１２：８８）为流动相，同时分离和测定制药生产流程中的烟肼、异烟酸和４－氧基吡啶的高效液相色谱法。方法各组分的质量浓度线性范围玫检出限分别为：异烟肼０．１１－１０６０ｍｇ／Ｌ和０．１１ｍｇ／Ｌ；异烟酸解和异烟酸０．０７－１０２０ｍｇ／Ｌ和０．０７ｍｇ／Ｌ；４－氰基吡啶０．２６－１０２３ｍｇ／Ｌ和０．２６ｍｇ／Ｌ。对高含量组分测定７次，其ＲＳＤ〈１％，微量组分的ＲＳ     

VCM—I型环境氯乙烯测定仪的研制

报导了一种用化学发光法来监测环境中氯乙烯的测定仪，其检测下限为１．０ｍｇ／ｍ＾３，线性范围为１．０￣２５５ｍｇ／ｍ＾３，响应时间〈２秒。本文阐述了其工作原理、仪器组成、性能指标，现场运行情况和抗干扰性能的测定等。     

同时测定药物多种有机溶剂残留量的气相色谱法

９５版中国药典收入了气相色谱法测定有机溶剂残留量。但不同溶剂采用不同柱温条件测定，甚是麻烦。美国药典可同时测定多种有机溶剂残留，但条件苛刻，操作繁复。为此，并研究提出了同时测定药物多种有机溶剂残留量的气相色谱法。测定条件是：４０１填充柱，柱温１５０℃，进样口温度２１０℃。气体流速氮气５０ｍｌ／ｃｍ＾２，空气０．５ｋｇ／ｃｍ＾２，氢气０．５ｋｇ／ｃｍ＾２，检测器为氢火焰，量程１０＾３，数据处理机衰减     

ICP—AES法直接测定金矿浸出液中的Au

研究了ＩＣＰ－ＡＥＳ法直接测定金矿浸出液中Ａｕ的各种条件，拟定了分析方法。方法的相对标准偏差（ＲＳＤ）为０．５３％，检出限（３ｓ）为０．０２μｍ／ｍｌ。该方法简便、快速，用于样品中Ａｕ的直接测定，结果满意。     

海光AFS—230双道原子荧光光度计特点及应用

ＡＦＳ－２３０型双道原子荧光光度计是北京海光仪器公司在１９９５年推出的最新一代氢化物发生原子荧光光度计，是全自动智能化的现代分子测试仪器。其对砷、硒、锑、铋等氢化物发生元素的检出限达到０．０２μｇ／Ｌ，铅达０．２μｇ／Ｌ，冷原子测汞达到０．００２μｇ／Ｌ，采用特殊试剂可直接测定溶液样品中的痕量镉，检出限优于０．００８μｇ／Ｌ，测定锌的检出限也达０．２μｇ／Ｌ。测量精度优于１％，测量样品速度大约１０     

紫外分光光度法测定酚醛树酯中游离酚

报告了紫外分光光度法测定酚醛树脂中游离酚含量的方法，波长为２７０ｎｍ时，１０－１００μｇ／ｍｌ苯酚与吸光度呈线性关系。相关系数Ｒ为０．９９９，平均回收率为１００．５９％，标准偏差０．８５１，变异系数为０．８４６％。     

冷原子吸收法测定植物样品中痕量汞

用重新组装的ＸＧ－３型测汞仪配合原子荧光仪的氢化物发生部分，对植物样品中痕量Ｈｇ进行冷原子吸收法测定。取５ｍＬ试液进行测定，灵敏度和检出限分别为０．３８μｇ／Ｌ（１％吸收）和０．０８μｇ／Ｌ。标准曲线线性范围０￣３０μｇ／Ｌ。对植物样品中汞含量０．０ｘｘμｇ／ｇ级进行测定（ｎ＝８），相对标准偏差小于６％。     

紫外分光光度法测定醋柳黄酮片总黄酮甙元的含量

建立了用紫外分光光度法测定醋柳黄酮片总黄酮甙元含量的方法。以无水乙醇为溶剂，测定波长为３７２ｎｍ，检测线性范围为１．８～１２．７μｇ／ｍｌ，γ＝０．９９９９，平均回收率为９９．９％，ＲＳＤ＝０．１９％。该方法准确、快速、简便，可作为醋柳黄酮片的含量测定方法。     

食品中微量砷的原子荧光光度法的测定

本文应用ＡＦＳ－２３０型双道原子荧光光谱仪对砷的测定方法进行了探讨。以饮料、粮果、方便面为样品，测定了其中微量总砷的含量。该方法的检出限为４．２６ｕｇ／Ｌ，线性范围为０～２００ｕｇ／ｍＬ。     

用电位滴定法测定工业用氢氧化钠中氢氧化钠和碳酸钠的含量

目前GB／T4348．1—2000测定工业用氢氧化钠中氢氧化钠和碳酸钠含量时，采用的是化学滴定法．而随着分析技术的发展，用电位滴定法是必然趋势。能够采用电位滴定法代替化学滴定法的前提条件是电位滴定法的准确度和精密度均满足国标的要求。用瑞士Metrohm682电位滴定仪对大量样品进行测定，数据表明，电位滴定法的准确度和精密度可以满足国标的要求。     

Sodium chromite as a friction-reducing material

Sodium chromite NaCrO₂ has a layered structure, with alternate layers of sodium and chromium interleaving oxygen layers. Although NaCrO₂ acts as a lubricant between metals in liquid sodium environments, exactly why it reduces the friction coefficient is not known. The purpose of this work was to develop knowledge about the properties of NaCrO₂ so that it could be applied more generally in liquid sodium systems. NaCrO₂ powder was prepared by reacting Na₂CO₃ and Cr₂O₃ at 900°C in argon. X-ray and electron spin resonance measurements confirmed that the material, when properly prepared, consisted entirely of NaCrO₂. NaCrO₂, which is stable in air, oxygen and argon at temperatures up to 200°C, is readily oxidized by air and oxygen at 600°C. The friction coefficient between NaCrO₂ specimens pressed from powder and a hemispherical stainless steel tip was measured at room temperature in air and helium and at temperatures up to 600°C in vacuum; the friction coefficient was found to lie in the range 0.20–0.45 for each of these conditions.     

食品中环己基氨基磺酸钠测定方法的研究

环已基氨基磺酸钠作为甜味剂替代糖精钠和蔗糖用在食品中,但过量食用会损害人体肝脏和神经系统。根据环已基氨基磺酸钠的物理化学特性,并参考GB/T5009.97-2003,对样品前处理和色谱分析方法进行优化改进,饮料样品的加标回收率为83.5%～99.04%。获得了更为完善而快速的检测方法。     

GD0511Na型钠离子浓度分析仪

本文以专利技术为核心,摒弃传统技术为依托的连续流动分析流路和手工标定方式,避免了分析过程中样品流相互交叉引起的滞后、静态人工标定和动态测量的差别以及流量变化诸因素的影响。经现场运行考核证明,该仪器具有精度和自动化程度高、工作可靠、维护量小、运行成本低等特点。     

铝电解质中钠的测定

提出用歉介的聚四氟乙烯烧杯代替铂皿,在低温近沸的盐酸溶液中分解试样,然后于原子吸收光谱仪上测其吸光度。     

Ball Bearings for High Temperature Liquid Sodium

A project has been conducted in support of the liquid metal cooled fast breeder nuclear reactor development, in which ball bearings have been designed, manufactured, and tested specifically for a typical reactor application involving operation in high temperature sodium.

A powder-processed tool steel was selected for rings and balls, and cages were manufactured from various candidate materials. Test bearings were made according to 7306 size (30 mm bore) envelope dimensions and tested under pure thrust loads up to 500 lbs, and speeds up to 1,000 rpm. A bearing life of 4 million shaft revolutions (67 hrs) was achieved in 600 F liquid sodium with an oxide concentration of 51 to 69 parts per million for the major part of the test. Excessive torque (greater than 30 pound inches), bearing noise (hash) and/or incipient binding constituted failure criteria. Wear of the balls and rings was identified as the principal operative failure mechanism determined by correlating operating performance and post-test microscopic and metrological examination. The results of this program confirmed that rolling contact bearings are viable mechanisms for use in high temperature liquid sodium systems and specific recommendations for LMFBR applications are made.     

The Effect of Concentration on Lubricating Properties of Aqueous Solutions of Sodium Lauryl Sulfate and Ethoxylated Sodium Lauryl Sulfate

The objective of this study was to formulate new ecological lubricating substances, primarily water-based, and to verify their tribological and physicochemical properties. Initially, simple binary solutions were investigated. Then, various additives were added depending on application targets. Two alkyl sulfates were selected as additives modifying lubricating properties of water: sodium lauryl sulfate (SLS) and ethoxylated sodium lauryl sulfate (ESLS). They have an identical hydrophobic part in the form of an alkyl chain consisting of 12 carbon atoms. The SO₄ ²⁻ anion forms the hydrophilic part in SLS molecules, whereas an ESLS molecule also contains two mers of ethylene oxide which cause an increase in its hydrophilicity relative to SLS. Both SLS and ESLS exhibit high surface activity measured by their surface tension. Micelles form in aqueous solutions of alkyl sulfates at low concentrations of the order of 1%, whereas the presence of liquid crystalline phases can be found at the concentrations of 40 and 70%. High surface activity and formation of structures in the solutions (micelles, mesophases) formed the basis for application of the compounds as additives modifying lubricating properties. Tribological properties of aqueous solutions of alkyl sulfates were verified with a four-ball machine (T02 tester) at a constant load of 2 kN. The values of friction coefficient (μ) were a measure of motion resistance, while the wear scar diameter (d) was a measure of wear. Alkyl sulfates significantly improve tribological properties of water. The coefficient of friction decreased sixfold and the wear scar diameter decreased by as much as twofold relative to the base. Non-monotonic changes in the tribological properties measured were observed as a function of concentration of additives. An attempt was made to relate those atypical changes with the presence of micelles and mesophases in both the surface phase and the bulk phase. In the model proposed the whole concentration range was divided into four areas in which tribological properties correspond well with physicochemical properties, particularly with the structures formed in solutions and at the interface.     

ASCS-15固定式碳酸钠混拌撬

本文对碳酸钠混拌橇的结构、工作原理进行了介绍。实践证明,此设备具有减轻工人劳动强度,改善工作环境等突出优点     

关于晶体钠的w～q关系及能带分析

钠作为一种碱金属,是固体物理学研究的一种重要材料。从固体物理学的几个重要概念出发,讨论钠晶体：色散关系：考虑钠晶格最近邻原子数为8个,写出运动方程,设解为角频率为ω的简谐振动Xm,n,l=Ae^i{a/2q（mi＋uj＋lk）-wt},从一般文献中提到的一维色散关系出发,并推导出钠三维晶格中格波的色散关系。能带理论：金属钠的费米面接近球面,从钠原子形成固体方面来考虑,由于数目庞大,原子间互相影响,电子能级分裂成相距很近的能级从而展宽为能带,文中利用紧束缚方法推导出钠晶格的能带宽度及固体电子论中的费米能量。     

用硫化钠制备二硫化钼纳米颗粒

将硫化钠与钼酸钠的水溶液混合,接着加入硫酸和催化剂溶液,生成棕色三硫化钼膏状沉淀。用蒸馏水反复洗涤除去杂质离子,经干燥去除水分,将干燥后的三硫化钼粉末在研钵中碾碎,在氢气氛中,在400～800℃下煅烧脱硫得到二硫化钼颗粒。用XRD和TEM对二硫化钼颗粒进行分析。结果表明：制备的二硫化钼颗粒的粒径在20～30nm之间。同时,对纳米二硫化钼颗粒的生成机制进行了讨论。