聚乙烯钢塑复合管导热系数的测定

聚乙烯钢塑复合管是新一代替代传统管道的新型管材，其导热系数的测试及相关的数据目前还没有报导。本文利用一维、稳态传热的基本规律，采用相对简单易行、测试成本低、较能真实反映实际情况的测试装置，对成都某企业的聚乙烯钢塑复合管导热系数进行了测试，获取了较满意的测试结果，并对测试结果的准确性进行了分析。所采用的测试方法及所获取的数据，对相应的生产厂家、设计、施工单位具有一定的指导意义。     

异辛酸钴合成工艺研究

考察了硫酸钴体系沉淀法合成异辛酸钴工艺中皂化反应温度及皂化时间、复分解反应时间、物料比、水洗温度和搅拌速度等因素对合成的影响,确定了合成的最佳工艺条件,建立了水相中钴的回收利用新工艺和测定方法。将整个工艺应用于全流程小试试验中,可保证钴的转化率达96.5%以上。     

多层分布式质量智能判定管理系统的设计与应用

对钢铁产品质量检验的多点分布性,建立了多层分布式的体系结构:对钢铁产品质量判定标准的规则多、类型多关联度高的特点,设计开发出多层推理机,实现了产品质量的智能化判定.介绍了系统主要功能模块及关键技术.     

Polymer Membrane Electrodes for Sensitive Potentiometric Determination of β-blockers

ABSTRACT

The construction of PVC matrix-type β-blockers (sotalol, carvedilol, and betaxolol) ion selective electrodes and their use for direct potentiometry of their respective species are described. The proposed sensors are based on the complex ion associates of β-blockers with tungstophosphate (TP) and Ammonium Reineckate (Rein) ionophoris in poly vinyl chloride membrane (PVC) with Dioctylphthalate (DOP) plasticizer. The four electrodes (Beta-TP), (Sota-TP), (Carve-TP), and (Cave-Rein) show stable potential response with near Nernstian slope of 50.8, 33.7, 32.35, and 33 mv per decade, range of concentration 10?2–10?7 M β-blockers. Selectivity coefficients data obtained for 11 different organic and inorganic ions are presented. The electrodes have fast response time (30 and 40 s) and were used over wide range of pH 4.5–8.5. Validation of the method according to the quality assurance standers shows suitability of proposed sensors for use in the quality control assessment of these drugs. The results obtained for the determination of β-blockers with the proposed electrodes show average recoveries of 100.78% and a mean standard deviation of ±1.2. The nominal are obtained. The data agree well with those obtained by standard methods.     

石墨炉原子吸收光谱法测定P91钢中Sb的含量

介绍了采用石墨炉原子吸收光谱法测定P91钢中Sb的含量。试样以盐酸、硝酸和高氯酸溶解,通过高氯酸冒烟除去氯化物。将试液移入石墨管中原子化,用Sb无极放电灯作光源,用原子吸收光谱仪于Sb217.6nm波长处测量其吸光度。     

Identification and determination of isoflavones in germinated black soybean sprouts by UHPLC−Q-TOF-MS mass spectrometry and HPLC-DAD

Ultra-performance liquid chromatography coupled with electrospray ionization tandem quadrupole time-of-flight mass spectrometry (UHPLC?Q-TOF-MS) and HPLC-DAD with an ultrasonic extraction method was developed for qualitative and quantitative compositions and contents in black soybean sprouts. Operational conditions of ultrasonic extraction were optimized by single-factor experiment. Phytochemical compositions of black soybean sprouts were identified by UHPLC?Q-TOF-MS in positive ion mode. A total of 23 compounds were tentatively characterized and identified by means of accurate mass and characteristic fragment ions. Among of them, the six isoflavones in different germinated black soybean sprouts were further quantified by HPLC-DAD. The results indicated that the calibration curves showed good linearity (r² > 0.9994). The intra-day and inter-day precision variations were less than 1.65% and 1.73%, respectively. The recoveries were in the range of 94.95–106.45%. The results indicated that the maximum amounts of isoflavones were produced on the fourth to fifth day germinated black soybean sprouts.     

ICP-AES法测定铅锌混合矿中的铁、铜、砷、锌、镉、汞

采用ICP-AES同时测定铅锌混合矿中铁、铜、砷、锌、镉、汞六种元素的含量,优化了实验条件,各元素的检出限为0.0069-0.07ug/mL,相对标准偏差为0.3%-4.72%,样品加标回收率为85.5%-112.8%。测试结果表明,该法测定铅锌矿的简单、准确、快速。     

ICP-MS测定锶矿石中稀土元素

研究了无水碳酸钠、草酸、硝酸钾混合溶剂半熔盐酸提取——等离子体质谱法同时测定锶矿石中15种稀土元素。检出限为0.006~0.015μg·g-1,变异系数(RSD,n=6)为1.95%~7.48%之间,加标回收率在91.4%~105.4%之间,通过分析国家一级标准物质GBW07831、GBW07832、GBW07833和GBW07834来验证方法的准确度,测定值和标准值吻合。稀土15项线性关系好,灵敏度和精密度较高,缩短了分析周期,为锶矿石中稀土15项的分析提供了测试方法。     

基于ADAMS的重载液压机械臂动力学建模与仿真

针对七自由度重载液压机械臂,建立精确、高效的重载液压机械臂系统逆动力学模型。利用牛顿-欧拉递推法、Spong柔性关节模型和Stribeck摩擦模型建立机械臂动力学模型;利用Creo完成机械臂三维模型搭建并导入ADAMS分析计算。与试验结果对比,确定系数均大于0.6,与无摩擦纯刚体模型计算结果相比有明显提升,验证了建模方法的准确性。     

煤中全硫测定方法的探讨

煤炭中全硫的分析，采用高温燃烧中和法进行测定，其中所用氧气采用纯氧瓶来供氧。因此，在试验中有很多不便。本文通过大量试验，从理论和实践中提出了直接以空气中氧来代替目前所用氧气钢瓶是完全可行的。