脉冲极谱溶出法测定高纯铟中镉和铜

本文研究了大量铟存在下能测定镉和铜的一系列支持电解质,研究了用JP—M1型脉冲极谱仪的仪器参数,用示波极谱仪研究了铟、镉、铜等离子的氧化电位和还原电位,了解了控制电解电位可排出大量铟对镉、铜的干扰,还研究了底液各成份浓度和镉、铜峰电流大小的关系及干扰离子影响情况。通过研究确定了在测定高纯金属铟中痕量镉和铜时先在5NHBr介质中用异丙醚萃取分离主体元素后,用0.5M乙二胺——0.5MKOH——5×10~(-5)MHg(NO_3)_2底液,在-1.1伏电解富集2分钟即可测定2毫微克/毫升的镉和铜。如改变仪器参数或增加富集时间可达更高的灵敏度,得出的波形良好,再现性好,此法操作简便、快速、测定样品中镉和铜的相对标准偏差<10％,镉的回收率92—98％,铜的回收率为69—103％,准确度符合要求。     

纯二氧化锆中痕量铜、铅和锌的汞膜电极反向极谱法连续测定

一、绪言 二氧化锆中铜、铅和锌的测定,有光谱法、原子吸收光谱法和极谱法等,用光谱法测定的报导较多,等用光谱法同时测定铜、铅和锌等元素,灵敏度为1×10~(-6)—1.5×10~(-2)％。采用原子吸收光谱结合内标法测定镉和铅等元素,灵敏度为10~(-5)—10~(-4)％,武内次夫等用交流极谱法同时测定Cu、Pb、Cd、Ni     

硝酸-氢氟酸密封消解同时测定茶园土壤中Cd和Pb的方法研究

硝酸和氢氟酸密封消解茶场土壤样品,用石墨炉原子吸收测定镉和铅含量．其检出限镉为0．053ngmL^-1、铅为0．1ngmL^-1,线性范围镉为0～2ngmL^-1、铅为0～50ngmL^-1．回收率在93．0％～104．0％．本方法简便了消解过程,一次消解能同时测定样品中的多种重金属．     

等温平台石墨炉原子吸收光谱法测定高纯铟中痕量杂质铅和砷

利用石墨炉原子吸收法，在等温平台条件下利用标准加入法直接测定了高纯铟中的痕量杂质铅和砷．并对石墨炉加热程序中的干燥时问、灰化温度及原子化温度进行了优化，同时也考察了介质酸度的影响．本方法中铅和砷的特征质量分别为37．8pg和40．7pg，相对标准偏差平均值分别为2．8％和2．0％，加标回收率分别为85．6％～95．4％和97．3％～105．0％，是测定高纯铟中杂质铅和砷的一种简单、快速、准确的方法．     

电感耦合等离子体质谱法测定谷类产品中7种元素

为建立准确、快速地同时测定谷类产品中微量重金属元素含量的方法,采用电感耦合等离子体质谱法测定藜麦和绿豆芽等谷类产品中砷、镉、铅、锰、铜、锌和铁等7种微量重金属元素.以硝酸和双氧水消解样品,调谐优化仪器分析条件,锌、砷、铜、锰和铁等5种元素选用KED模式,铅和镉选用STD模式,以标准曲线法进行测定.结果显示：砷、镉、铅、锰、铜、锌和铁的线性回归方程分别为y=1.49×10²x+0、y=3.06×10²x+0、y=1.026 7×10⁴x+0、y=1.029×10³x+0、y=1.088×10³x+0、y=2.67×10²x+0和y=3.4×10¹x+0;砷、镉、铅、锰和铜的线性范围均为0.10～800.0μg·L^-1,锌的线性范围为5.00～300.0μg·L^-1,铁的线性范围为5.00～800.0μg·L^-1,相关系数均在0.999 4～0.999 6之间;检出限在6....     

利用ICP—AES法测定中药材中铅、镉、铜含量的研究

建立了利用ICP—AES测定中药材中重金属元素铅、镉、铜的轴向观测方法,对轴向观测和横向观测的精密度结果和样品测定结果进行了比较。结果表明,采用轴向观测方式测得Pb、cd、cu的检出限（Ct．）分别为3．1ng·mL^-1、0．4ng·mL^-1、1．7ng·mL^-1;相对标准偏差（RSD）均小于5％;平均加标回收率分别为102．3％、101．8％、101．1％。轴向观测方式能满足中药材中铅镉铜的检测要求,横向观测方式不符合要求。     

硫氰酸铟—碱性染料水相光度法测定痕量铟

本文报道了利用一系列碱性染料与硫氰酸铟配阴离子反应的水相直接光度法测定铟的分析方法,在水溶液中,甲基紫、乙基紫、结晶紫、甲基绿、灿烂绿、孔雀绿、碘绿和罗丹明B,罗丹明6G、乙基罗丹明B、丁基罗丹明B与硫氰酸铟配阴离子均形成高灵敏度离子缔合物,其摩尔吸光系数均高于10~5数量级,最高可达8×10~5,是目前最灵敏的铟的测量方法之一。这些测定方法可用于痕量铟的测定     

火焰原子吸收法连续测定锑白中铜、铅、镉、铋、铁含量

改进国家标准制定的锑白(三氧化二锑)中铜、铅、镉、铋、铁含量的方法,利用火焰原子吸收光谱法(FAAS)连续测定铜、铅、镉、铋、铁含量。探讨了样品前处理、基体元素及共存元素的干扰情况、介质以及酸度的影响,确定了各元素分析最佳条件。试验结果表明,该方法能满足锑白中铜、铅、镉、铋、铁的连续测定。该方法的回收率:铜99.25%～108.75%,铅99.44%～105.34%,镉99.67%～102.23%,铋99.37%～105.73%,铁99.10%～112.50%;标准偏差:铜(4.22～5.16)×10~(-5),铅(9.45～9.65)×10~(-4),镉(7.38～7.41)×10~(-4),铋(5.68～7.07)×10~(-5),铁(1.14～1.25)×10~(-4);相对标准偏差:铜6.98%～8.78%,铅2.02%～2.64%,镉2.44%～3.22%,铋1.26%～1.63%,铁2.70%～3.14%。     

硫酸锌中微量铅镉的极谱法连续测定

在盐酸-磷酸-酒石酸-碘化钾-抗坏血酸底液中，Pb（Ⅱ）于-0．56V（vs，SCE），Cd（Ⅱ）（vs，SCE）于-0．69V产生灵敏的催化吸附波，铅镉的浓度在0．01～2ug·mL^-1范围内与波高呈线性关系，大量的锌和硫酸根离子不干扼测定。试样经水直接溶解后，在上述条件下进行测定，锸标准回收卒：97．80％～105.17％，相对标准偏差：5．86％～9．32％;镉标准回收率：95．38%～107．32％，相对标准偏差：9．38％～13．86％。适用于硫酸锌中铅、镉含量〉0．5μg·g^-1试样的测定。     

同位镀铋膜电极测定水样中铅和镉离子的研究

采用阳极溶出伏安法,以铋膜电极替代汞膜电极测定水样中痕量铅和镉离子。考察并优化了同位镀铋膜测定铅、镉的条件。实验结果表明：铅和镉在铋膜电极上可得到灵敏的溶出峰,峰高和溶出电位与汞膜电极法相近,使用铋膜电极可避免使用汞膜电极带来的环境污染。当电沉积时间为5min时,铅和镉的检出限分别达1．0&#215;10^-7moL／L和5．0&#215;10^-8mol／L。同时,由于每次溶出后可方便地将铋膜溶解更新,因此,能保证各次测定的重现性。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-