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多组份混合基体改进剂石墨炉原子吸收法测定全血中铅 被引量:7
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作者 王立 于笑宇 +1 位作者 施家威 金米聪 《中国卫生检验杂志》 CAS 2008年第7期1313-1314,1383,共3页
目的:建立一种新型的全血中铅的多组份混合基体改进剂石墨炉原子吸收测定方法。方法:全血样用5%硝酸脱去蛋白,经离心后取上清液采用优化进样程序直接进样,使用多组份混合基体改进剂,石墨炉原子吸收法测定。结果:连续3个月的小牛... 目的:建立一种新型的全血中铅的多组份混合基体改进剂石墨炉原子吸收测定方法。方法:全血样用5%硝酸脱去蛋白,经离心后取上清液采用优化进样程序直接进样,使用多组份混合基体改进剂,石墨炉原子吸收法测定。结果:连续3个月的小牛血铅样国际实验室间比对试验结果均为优秀,方法的精密度为2.74%~5.20%,回收率为98.7%~102%。结论:该法具有测定结果可靠、成本节省、操作简便、不需消化等优点,可用于全血中铅的测定,尤其适合大批量样品测定。 展开更多
关键词 石墨炉原子吸收法 多组混合基体改进剂 全血
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用连续热力学方法计算多组份混合物 被引量:1
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作者 徐忠 《工程热物理学报》 EI CAS CSCD 北大核心 1989年第1期16-18,共3页
多组份混合物常规上总是用混合物中各组份分数来加以描述。这种描述方法一般称为离散组份方法。最近,对多组份混合物,提出了不用离散组份,而代之以用一个概率密度函数来加以描述。建立在这样描述基础上的热力学理论与计算方法称为“连... 多组份混合物常规上总是用混合物中各组份分数来加以描述。这种描述方法一般称为离散组份方法。最近,对多组份混合物,提出了不用离散组份,而代之以用一个概率密度函数来加以描述。建立在这样描述基础上的热力学理论与计算方法称为“连续热力学”。直到最近,连续热力学方法才开始得到发展。 展开更多
关键词 连续热力学 计算 多组混合
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多组份混合工质掺混机理数值研究 被引量:1
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作者 蔡剑钢 袁新 叶大均 《工程热物理学报》 EI CAS CSCD 北大核心 2000年第5期563-566,共4页
本文采用高分辨率的数值算法,分析了热解炉内多组份湍流流场。在冷态掺混实验以前对其进行了数值模拟以指导实验,数值模拟的结果定性上得到了冷态掺混实验的证实。为研究旋焰乙炔热解炉喷油联产乙烯的化学反应机理及工程放大问题提供... 本文采用高分辨率的数值算法,分析了热解炉内多组份湍流流场。在冷态掺混实验以前对其进行了数值模拟以指导实验,数值模拟的结果定性上得到了冷态掺混实验的证实。为研究旋焰乙炔热解炉喷油联产乙烯的化学反应机理及工程放大问题提供了依据。 展开更多
关键词 高分辨率格式 多组混合工质 掺混机理
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(Sn_(1-x)Zn_(x))_(57)(In_(0.78)Bi_(0.22))_(43)低熔点无铅焊料的微观结构表征
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作者 张天宇 程清 +2 位作者 竺恒宇 魏琴琴 徐先东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第1期201-208,共8页
为了寻求一种应用于三维集成电路低温焊接的无铅焊料,基于多组元混合的概念设计并表征(Sn_(1-x)Zn_(x))_(57)(In_(0.78)Bi_(0.22))_(43)(x=0.10,0.15,0.20,摩尔分数,%)四元合金。采用扫描电子显微镜、X射线衍射仪和差示扫描量热仪研究... 为了寻求一种应用于三维集成电路低温焊接的无铅焊料,基于多组元混合的概念设计并表征(Sn_(1-x)Zn_(x))_(57)(In_(0.78)Bi_(0.22))_(43)(x=0.10,0.15,0.20,摩尔分数,%)四元合金。采用扫描电子显微镜、X射线衍射仪和差示扫描量热仪研究合金的显微组织、热性能和润湿性。结果表明,合金由金属间化合物BiIn_(2)、In_(0.2)Sn_(0.8)和富Zn固溶体组成。随着Zn添加量的增加,BiIn_(2)和富Zn相的体积分数增加。合金的熔点低至70℃,源自低熔点金属间化合物In_(0.2)Sn_(0.8)和BiIn_(2)的形成;合金具有良好的润湿性,润湿角约为40°。在合金和Cu板的界面结合处形成一种薄而坚韧的Cu_(5)Zn_(8)层,提高焊点可靠性。研究表明,通过多组元混合概念设计合金可以有效提高焊料的焊接性能。 展开更多
关键词 无铅焊料 多组混合 低熔点 显微 热性能
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γ-多聚谷氨酸产生菌高效诱变育种的研究 被引量:7
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作者 陈咏竹 田天丽 +5 位作者 卢锦 陈智 王嫱 高婷 张兴宇 孙启玲 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第2期389-394,共6页
设计了几组不同的诱变条件对γ多聚谷氨酸生产菌BacilluslicheniformisATCC9945A进行诱变,诱变后将所有菌株混合,以此未经筛选的混合菌共同发酵,并以终产量为指标对发酵条件进行连续的定向调控,使发酵条件逐渐向高产正突变株倾斜,产量... 设计了几组不同的诱变条件对γ多聚谷氨酸生产菌BacilluslicheniformisATCC9945A进行诱变,诱变后将所有菌株混合,以此未经筛选的混合菌共同发酵,并以终产量为指标对发酵条件进行连续的定向调控,使发酵条件逐渐向高产正突变株倾斜,产量得以逐步提高.同时在混合菌状态下找到适合高产正突变株的发酵条件,以此发酵条件作为筛选平板,对混合菌分离纯化,选育到γPGA高产菌Zγ29,产量是出发菌株的4.14倍,筛选条件即为该突变株的最佳发酵条件. 展开更多
关键词 复合诱变 多组混合 复杂系统定向调控技术 高效诱变育种 γ-多聚谷氨酸
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Modeling of Mass Transfer in Nonideal Multicomponent Mixture with Maxwell-Stefan Approach 被引量:2
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作者 宋一鸣 宋金荣 +3 位作者 龚明 曹彬 杨燕红 马晓迅 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第3期362-371,共10页
The Intalox metal tower packing was used to simulate an industrial relevant extractive distillation column for purifying azeotropic multicomponent mixture.In order to explain the inconsistencies in the modeling of tra... The Intalox metal tower packing was used to simulate an industrial relevant extractive distillation column for purifying azeotropic multicomponent mixture.In order to explain the inconsistencies in the modeling of transfer process in nonideal multicomponent distillation column,a method was developed with equilibrium stage models(EQ)and non-equilibrium model(NEQ)incorporated with Maxwell-Stefan diffusion equations in the framework of AspenONE simulator.Dortmund Modified UNIFAC(UNIFAC-DMD)thermodynamic model was employed to estimate activity coefficients.In addition,to understand the reason for the diffusion against driving force and the different results by EQ and NEQ models,explicit investigations were made on diffusion coefficients, component Murphree efficiency and mass transfer coefficients.The results provide valuable information for basic design and applications associated with extractive distillation. 展开更多
关键词 rate based model equilibrium model mass transfer coefficient Murphree efficiency extractive distillation simulation
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Chromatographic separation of Be(Ⅱ) from Mg(Ⅱ), Ca(Ⅱ), Sr(Ⅱ) and Ba(Ⅱ) using poly[dibenzo-18-crown-6] and L-arginine
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作者 Sandip R. Sabale Baburao S. Mohite 《Journal of Chemistry and Chemical Engineering》 2009年第6期37-43,共7页
A simple and selective method for the separation of Be(Ⅱ) was developed using poly[dibenzo-18-crown-6] as a stationary phase in column chromatography. The study was carried out in L-arginine medium. 1.0-8.0 M HCl a... A simple and selective method for the separation of Be(Ⅱ) was developed using poly[dibenzo-18-crown-6] as a stationary phase in column chromatography. The study was carried out in L-arginine medium. 1.0-8.0 M HCl and CH3COOH, 0.5-8.0 M HBr, HClO4 and H2SO4, 0.2-1.0 M EDTA and 0.02-0.12 M ammonium oxalate were found to be an efficient eluents for Be(Ⅱ). The capacity of polymer was 0.554-0.01 mmol/g of crown polymer. The tolerance limit of various cations and anions were reported. Be(Ⅱ) was quantitatively separated from Mg(Ⅱ), Ca(Ⅱ), Sr(Ⅱ) and Ba(Ⅱ). The selective separation of Be(Ⅱ) was possible from multicomponent mixtures. The method was extended to determine Be(Ⅱ) from geological samples. Method was simple, rapid and selective having good reproducibility (approximately4-2%). 展开更多
关键词 Be(Ⅱ) poly[dibenzo-18-crown-6] L-ARGININE SEPARATION column chromatography
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Explosive limits of mixed gases containing CH_4,CO and C_2H_4 in the goaf area 被引量:8
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作者 DENG Jun LUO Zhenmin +1 位作者 WU Xiaochun HU Yaoyuan 《Mining Science and Technology》 EI CAS 2010年第4期557-561,共5页
The explosive gases CO and C2H4, released mainly flammable gases during the process of coal self-ignition, are of the most important ingredients of the multi-component gases in goal areas, along with CH4. We have dete... The explosive gases CO and C2H4, released mainly flammable gases during the process of coal self-ignition, are of the most important ingredients of the multi-component gases in goal areas, along with CH4. We have determined some of the parame- ters of explosive properties of the one-component gases CH4, CO and C2H4 using an explosive trial device of polybasic explosive gas mixtures and emphasized particularly the effect on the limits of explosive concentration of the binary explosive mixed gases CH4+CO, CH4+C2H4, as a function of the amount of CO, C2H4 and inert flame resisting gases (N2, CO2). The experimental results show that the effect of inert gases on the explosive limits of mixed gases, given the property of explosive gas, is obvious: the inert gases (N2, CO2) possess some inhibitory effects on the explosion of the multi-component explosive gas mixtures. The results will provide some experimental support to suppress the occurrence of the gas explosions in goaf areas and provide some directions for designing explosion-proof electric equipment and fire arresters. 展开更多
关键词 gob indication gas of self-ignition GAS concentration explosive limits
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气相色谱质谱法在运动员药检中的应用
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作者 祝英 潘淑敏 《辽宁体育科技》 1996年第1期4-5,共2页
竞技体育发展到今天,除依靠科学技术的发展,采用各种训练手段来提高运动成绩外,一些禁用的药物也作为提高运动成绩的手段而被运动员服用。药物的使用违反了体育本来的精神和原则。
关键词 运动员 色谱质谱法 提高运动成绩 多组混合 气相色谱 分子离子峰 定性分析 定性鉴定 GC/MS 竞技体育发展
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Uniform design ray in the assessment of combined toxicities of multi-component mixtures 被引量:22
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作者 Shu-Shen Liu Qian-Fen Xiao +1 位作者 Jin Zhang Mo Yu 《Science Bulletin》 SCIE EI CAS CSCD 2016年第1期52-58,共7页
Multi-component mixture(MCM) is a complicated chemical system that contains a great deal of mixture rays with various mixture ratios, and each ray includes many mixtures with different concentration levels.Currently, ... Multi-component mixture(MCM) is a complicated chemical system that contains a great deal of mixture rays with various mixture ratios, and each ray includes many mixtures with different concentration levels.Currently, in combined toxicity field, almost all studies on MCM focus on the mixtures designed by the equivalenteffect concentration ratio(EECR) procedure. However, the EECR mixtures cannot represent the whole mixture system because the EECR mixtures are located on one mixture ray in concentration space formed by multiple components. In our view, some optimal experimental design such as the uniform design(UD) should be used to effectively select many representative mixture rays from the MCM system,instead of single EECR ray. The uniform design ray(UDray) integrating UD idea with fixed-ratio ray design can systematically and comprehensively measure the combined toxicity changes in the MCM system. This review introduces the operation method, construction of uniform table and corresponding usable table, and some cases of application of the UD-ray to help readers easily use UD-ray in their MCM toxicity assessment. 展开更多
关键词 Chemical mixture Uniform design Ray design Mixture ratio. Concentration-responserelationship Toxicity interaction
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