标准加入双波长光度法同时测定化学镀层中的镍钴

研究了标准加入双波长光度法同时测定化学镀层中镍钴的试验条件,并对镍钴合成样和实际镀层样品进行了测定。在pH3．8的乙酸-乙酸钠缓冲溶液中,采用显色剂5-Br-PADAP测定镍钴的测定波长和参比波长分别为564nm和592nm,镍在两个波长下符合比耳定律的范围分别为0—50μg／25mL和0—40μg／25mL,钴为0—50μg／25mL。用该法对镍钴合成样和实际化学镀钴-镍-磷及镍-钴-磷合金镀层中镍、钴的同时测定,回收率在95％-105％之间,结果令人满意。     

电感耦合等离子体发射光谱法(ICP-AES)测定铀矿石中微量钪、硒、铼

用HF—HNO3—HClO4溶解样品，在0．6mol／L盐酸介质中，用ICP—AES法对铀矿石中钪(Sc)、硒(Se)、铼(Re)进行了测定．测得各元素的测定下限分别为：Sc0．03μg/mL、Se0．03μg/mL、Re0．016μg/mL．低、中、高3种浓度的平均标准加入回收率为96％～106％，相对标准偏差小于8％。     

用导数分光光度法同时测定微量钴和镍

以5—Br—PADAP为显色剂,用二阶导数分光光度法对微量钴镍进行了同时测定,按“零交法”取569nm和616nm的峰——零导数峰值分别对镍钴定量,服从比耳定律的线性范围分别为0～14μg/25mL和0～22μg/25mL.样品的测定和回收实验表明,该方法准确、灵敏,符合测定要求,与原子吸收法的分析结果相吻合。     

环境生物样品中放射性核素铷铯的测定方法探讨

环境生物样品低温灰化后，混合酸溶解，转成碱性介质。在碱性介质中，采用4-叔丁基-2(α-甲苄基)-苯酚(t—BAMBP)进行萃取，有机相直接进行原子吸收测定。该方法简便、快速、灵敏。标准回收率分别为铷97—104％、铯99—103％；检出限分别为铷0．07μg/mL，铯0.05μg/mL。     

DPPH·法评价葡萄籽提取物淬灭自由基的方法研究

通过DPPH·法测定葡萄籽梯度提取各组分清除自由基能力的研究,结果表明,最佳活性测定样品浓度范围1.0-10μg/mL、放置时间30min、温度25℃,运用此法测得的清除率在25-80%之间,具有较高的灵敏度和准确度。样品浓度0.25-10μg/mL与活性呈正相关关系,其中从1.0-5.0μg/mL范围内有良好的线性关系。当样品用量低于25μg/mL时,样品自身的贡献微不足道,清除率按公式:IP(%)=[(Ac-Ai)/Ac]×100计算。浓度大于25μg/mL时,其结果计算必须扣除样品背景影响IP(%)=[1-(Ai-Aj)/Ac]×100%,否则可能得出样品无抗氧化性或有助氧化作用的错误结论。     

微量Pt,Pd和Rh的在线分离富集与FAAS测定

提出用VS-Ⅱ型碱性阴离子交换纤维流动注射在线分离富集-火焰原子吸收光谱法(FI-FAAS)测定复杂样品中的Pt,Pd和Rh的分析方法.该方法检测限低,Pt:0.064μg/mL,Pd:0.074 μg/mL,Rh:0.025μg/mL,采样频率大,可用于复杂样品中痕量贵金属的测定.     

火焰原子吸收法测定指甲中的微量镁、锌

使用非完全消化法处理指甲样品,建立非完全消化-火焰原子吸收光谱法快速测定指甲中镁、锌的分析方法。以Sr2＋作为镁的释放剂。用工作曲线法测定。对样品处理条件、化学干扰、硝酸的影响、介质的影响、试液与空白溶液粘度一致性及背景吸收干扰进行了考察。测定结果的相对标准偏差：镁3.4%、锌5.2%。测定结果与灰化法一致,测定结果的相对误差：镁-1.2%、锌-2.3%。,检出限：镁0.0017μg/mL、锌0.0119μg/mL。方法简便。     

高效液相色谱法测定冰茶栓中的咖啡因

本叙述了应用HPLC法对戒毒新药冰茶栓中咖啡因含量的测定方法，样品经1：1的乙醚-石油醚溶化，用1：1的甲醇水溶液提取，用20mmol／1醋酸铵缓冲液和甲醇(80：20)作为流动相，经ODS-C18柱分离，紫外270nm检测，加标平均回收率为98．22％，相对标准偏差(CV)日内为0.30％，日间为0．97％，最低检出浓度为25μg/L，最低定量浓度为100μg/L，线性范围为10～250μg／mL，相关系数为0．9999。     

基于荧光多元猝灭响应原理的膜传感器测定正己烷中的噻吩、正辛硫醇及单质硫

为研究测定石油制品中藏化物的光纤化学传感器提供实验基础。用溶胶-凝胶法制备芘丁酸-二氧化硅敏感膜(试剂项),根据荧光多元猝灭响应的原理分别测定正己烷中噻吩、正辛硫醇及单质硫的含量。结果:噻吩、正辛硫醇及单质硫分别在10.6-265μg/ml、0.84-16.80μg/ml、0.75-15.0μg/ml浓度范围内与lg(F0/F)成线性关系,相关系数分别为0.9984、0.9981、0.9993。检出限分别为10.6μg/ml、0.81μg/ml、0.75μg/ml,平均回收率分别为105.0±7.7％、103.2±7.5％、97.5±1.4％。结论:用芘丁酸-二氧化硅试剂相分别测定正已烷溶液中的噻吩、正辛硫醇及单质硫的含量可取得较好的精密度,回收率和可逆度。     

微波等离子体炬原子发射光谱法测定芦荟中金属元素的含量

采用微波消解技术消解芦荟,利用微波等离子体炬原子发射光谱法(MPT—AES)测定了元江芦荟和华芦荟中Ca、Mg、Fe、Zn元素的含量。考察了分析谱线、微波前向功率、载气流量、工作气流量、氧屏蔽气压力等实验参数对元素测定的影响,优化了最佳实验条件。方法对Ca、Mg、Fe、Zn元素的检出限分别为5.62ng/mL,3.03ng/mL,78.36ng/mL,25.41ng/mL;线性范围分别为(0.05—100)μg/mL,(0.01—100)μg/mL,(0.2—20)μg/mL,(0.1—20)μg/mL;相对标准偏差均小于1.96%,回收率在96.5%—102.4%之间。实验结果显示,本方法准确、快速、操作简便,具有一定的实际应用价值,且华芦荟与元江芦荟中金属元素含量基本相同,但华芦荟中铁元素含量比元江芦荟含量丰富。     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that