应用分光光度法对Fe-Si-B-Nb-Cu合金中铌含量的测定进行了研究.对试样的预处理方法、试剂和显色剂的加入量以及显色时间与温度等条件进行了优化.在优化条件下,于650 nm波长处对试样进行比色分析.实验结果表明,该方法测定结果与电感耦合等离子体发射光谱法测定结果相符,其回收率为94.0％～99.5％,测定结果的相对标准偏差小于1.0％(n=11),该方法操作简便、分析成本低,能满足纳米晶合金中铌含量的测定精度.

关键词：铌含量;Fe-Si-B-Nb-Cu纳米晶;光度法;quantity of niobium;nanocrystal Fe-Si-B-Nb-Cu;spectrophotometric method

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无机改性膨润土制备环境功能材料的方法主要有无机盐改性、无机柱撑.介绍了无机盐改性膨润土、无机柱撑膨润土环境功能材料的水污染控制作用原理,并详细综述了两种无机改性膨润土环境功能材料在水污染控制中的研究新进展,提出了无机改性膨润土作为环境功能材料应用于水污染控制需进一步研究的问题.

关键词：膨润土;无机改性;环境功能材料;水污染;吸附;催化;bentonite;inorganic modification;environment function material;water pollution;adsorption;catalysis

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在浆态床反应器中,对Fe-Mn催化剂上CO加氢合成低碳烯烃的反应性能进行了研究,考察了不同温度、空速和压力下Fe-Mn催化剂的催化性能,并借助XRD和N2物理吸附等手段对催化剂进行了表征.实验结果表明,Fe-Mn催化剂在运行300h后达到稳定运行状态.反应参数的适当调变,可有效提高Fe-Mn催化剂的活性和低碳烯烃收率,并使产物分布得到优化在n(H2):n(CO)=2、320℃、2.0 MPa、合成气空速1 000 h-1的条件下,CO转化率83.10％,CH4选择性11.88％,C5+烃选择性39.06％,C2～4烃中烯烃与烷烃的质量比3.59,低碳烯烃收率38.50 g/m3(基于H2与CO的总体积).

关键词：低碳烯烃；铁-锰催化剂；浆态床反应器；合成气；费托合成

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通过在多层量子点体系中引入应变补偿层,改变量子点系统的应力场分布,可以控制生长过程中量子点的大小均匀性和密度,最终获得高质量、高密度的多层量子点体系,应用到量子点光电器件中,可改善器件的电学和光学性能.介绍了应变补偿层在量子点体系中作用的原理,常用的应变补偿材料体系,以及目前国内外对应变补偿技术的研究状况,最后提出了现存的问题和今后的发展方向.

关键词：InAs量子点;应变补偿技术;太阳电池

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The purpose of this Toxicological Review is to provide scientific support and rationale for the hazard and dose-response assessment in IRIS pertaining to chronic exposure to tetrachloroethylene. It is not intended to be a comprehensive treatise on the chemical or toxicological nature of tetrachloroethylene.

关键词：电子信息；信息系统；四氯乙烯；评论

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Dioxins and dioxin-like compounds (DLCs), including polychlorinated dibenzo-dioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls, are structurally and toxicologically related halogenated dicyclic aromatic hydrocarbons. Dioxins and DLCs are released into the environment from several industrial sources such as chemical manufacturing, combustion, and metal processing; from individual activities including the burning of household waste; and from natural processes such as forest fires. Dioxins and DLCs are widely distributed throughout the environment and typically occur as chemical mixtures. They do not readily degrade; therefore, levels persist in the environment, build up in the food chain, and accumulate in the tissues of animals. Human exposure to these compounds occurs primarily through the ingestion of contaminated foods (Lorber et al., 2009), although exposures to other environmental media and by other routes and pathways do occur. The health effects from exposures to dioxins and DLCs have been documented extensively in epidemiologic and toxicological studies. 2,3,7,8-Tetrachlor odibenzo-p-dioxin (TCDD) is one of the most toxic members of this class of compounds and has a robust toxicological database. Characterization of TCDD toxicity is critical to the risk assessment of mixtures of dioxins and DLCs because it has been selected repeatedly as the 'index chemical' for the dioxin toxicity equivalence factors (TEF) approach.

关键词：电子信息；信息系统；EPA；综合风险信息系统；IRIS；分析

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关键词：化肥；进口关税；配额总量

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The purpose of this toxicological review is to provide scientific support and rationale for the hazard and dose-response assessment in IRIS pertaining to chronic exposure to tetrahydrofuran. It is not intended to be a comprehensive treatise on the chemical or toxicological nature of tetrahydrofuran. The intent of Section 6, Major Conclusions in the Characterization of Hazard and Dose Response, is to present the major conclusions reached in the derivation of the reference dose, reference concentration and cancer assessment, where applicable, and to characterize the overall confidence in the quantitative and qualitative aspects of hazard and dose response by addressing the quality of data and related uncertainties. The discussion is intended to convey the limitations of the assessment and to aid and guide the risk assessor in the ensuing steps of the risk assessment process.

关键词：电子信息；信息系统；四氢呋喃；评论

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报告从战略性分析、环境信息、竞争对手情报、资讯信息快报、市场行情与数据分析等几个方面进行了分析评论。

关键词：石油化工；战略性分析；环境信息；竞争对手情报；资讯信息快报；市场行情

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关键词：尿素；市场价格

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