钴(Ⅱ)与α-联呋喃甲醛二肟的络合吸附催化波的研究

在pH 10.8的含NO-2的NH3/NH4Cl缓冲液中,使用单扫描示波极谱仪测定了α-联呋喃甲醛二肟与钴(Ⅱ)在-1.18 V处形成的灵敏的络合吸附波,此方法用于测定维生素B12针剂中痕量钴的含量,结果满意.其一阶导数峰峰电流与Co2+浓度在4×10-10 g·mL-1～4×10-8 g·mL-1范围内呈线性关系,检出限为2×10-10 g·mL-1.使用不同电化学方法对该极谱波的性质进行了研究,表明该极谱波是一具有催化作用的络合吸附波,电极过程不可逆.     

头孢氨苄在磷酸盐缓冲液中的单扫描极谱法

采用单扫描极谱法研究了头孢氨苄在pH 7.4的KH2PO4-K2HPO4缓冲溶液中的极谱行为,发现在-1.2V附近产生一个灵敏的还原峰.还原峰峰电流与头孢氨苄的浓度分别在2.7×10-7～2.7×10-6mol/L和2.7×10-6～1.0×10-3mol/L范围存在良好的线性关系,检测限为2.7×10-8mol/L(S/N=3).用于药片中头孢氨苄测量,加入回收率为94.0%～102.0%.     

维生素B2在硫酸溶液中的单扫描极谱氧化波及其应用

报道了维生素B2在酸性溶液中的极谱氧化波及其应用.在0.12 mol/L的硫酸溶液中,维生素B:在-0.04V(vs.SCE)处产生一个灵敏的吸附性氧化峰,其二阶导数波峰尖锐、对称,波高与0.025×10-6～9.0×10-6g/mL范围内的维生素Bz呈线性关系,相关系数为0.997,检出限达0.020×10-6g/mL对于5.0×10-6g/mL的维生素B2平行进行11次测试,RSD为1.10%.极谱波的波高在室温下可以稳定8 h.讨论了测定中干扰物质中的影响及机理包括循环伏安图,温度系数,表面活性剂的影响和电毛细管曲线.结果降低了检测下限.     

玻碳电极吸附循环伏安法测定维生素B2

目的研究维生素B2在玻碳电极表面吸附的电化学行为及定量分析方法.方法玻碳电极在8.0 mol/L HNO3介质中,于+0.6～+2.O V(vs.SCE)的电位范围内进行循环扫描电活化后,维生素B2在电极表面具有很强的吸附性,在底液为0.05mol/L柠檬酸+0.1 mol/L Na2HPO4(pH=4.9)的介质中,吸附电位-0.3 V,在0～-0.7 V的范围内,以90mV/s的速度进行循环伏安扫描.结果实验表明VB2在电极表面具有可逆吸附波的特征,VB2浓度与峰电流在6.O x 10-～7.0×10-6 mol/L之间成线性关系,检测限为1 0×10-8 mol/L.结论建立了维生素B2在玻碳电极表面的电化学分析方法,将该法运用于实际样品药片中VB2含量的测定,获得满意的结果.     

玻碳电极吸附循环伏安法测定维生素B_2

目的 :研究维生素B2 在玻碳电极表面吸附的电化学行为及定量分析方法 .方法 :玻碳电极在 8.0mol/LHNO3 介质中 ,于 + 0 .6～ + 2 .0V (vs.SCE)的电位范围内进行循环扫描电活化后 ,维生素B2 在电极表面具有很强的吸附性 ,在底液为 0 .0 5mol/L柠檬酸 + 0 .1mol/LNa2 HPO4 (pH =4 .9)的介质中 ,吸附电位 - 0 .3V ,在 0～ - 0 .7V的范围内 ,以 90mV/s的速度进行循环伏安扫描 .结果 :实验表明VB2 在电极表面具有可逆吸附波的特征 ,VB2 浓度与峰电流在 6.0× 10 - 8～ 7.0× 10 - 6 mol/L之间成线性关系 ,检测限为 1.0× 10 - 8mol/L .结论 :建立了维生素B2 在玻碳电极表面的电化学分析方法 ,将该法运用于实际样品药片中VB2 含量的测定 ,获得满意的结果 .     

巴比妥类药物的极谱分析方法

研究了单扫描极谱法分别测定巴比妥、苯巴比妥、异戊巴比妥的方法,在0.1 mol·L-1H2SO4的溶液中,巴比妥、苯巴比妥、异戊巴比妥与吡啶铜体系均产生一个灵敏的极谱波,该吸附还原波的二阶导数峰电流与其浓度在1.0×10-6～2.0×10-3mol·L-1范围内都呈线性关系,本方法可用于原料药与片剂的分析.     

铑—1—（2—吡啶偶氮）萘酚络合吸附波测定微量铑

铑和 1- (2 -吡啶偶氮 )萘酚 (PAN)在 p H=5.0 0的邻苯二甲酸氢钾—氢氧化钠介质中生成具有电活性的络合物 ,在单扫示波极谱 - 0 .6 7V(vs.SCE)处呈现良好极谱还原波 .该波二阶导数峰高与铑的浓度在 2 .3× 10 -8～ 4 .8× 10 -7mol· L-1和 4 .8× 10 -7～ 9.7× 10 -6mol· L-1范围内呈线性关系 ,检出限为 7.6× 10 -9mol· L-1,并成功的用于贵金属合成样及合金样品中铑含量的测定 .实验结果表明该极谱波属络合吸附波     

四环素的极谱法测定

四环素的检定方法,药物学上用微生物检定法,也有用分光光度法、色谱法。1952年以后有用极谱法的报导。Chatten等用直流极谱在硼酸底液中测定了0.01～0.125mg/ml的四环素。Olliff等在HAc-NaAc缓冲液中用交流极谱测定了2×10~(-6)～1×10~(-4)M四环素。Bard报导用微分脉冲极谱检测下限达0.2ppm。我们用直流、交流、示波和微分脉冲极谱研究了四环素在醋酸、硼酸、磷酸盐的缓冲液中的极谱行为,提高了分析灵敏度,并应用于四环素药片、软膏、眼膏和针剂中四环素含量的测定,得到满意的结果。     

以双(N-甲基-N-苯基氨基二硫代甲酸)1,4-丁二醇酯为载体的PVC膜银离子选择电极的研究

报道了以双(N-甲基-N-苯基氨基二硫代甲酸)1,4-丁二醇酯为载体的PVC膜电极的响应行为.结果表明:该选择电极对银离子有良好的灵敏度和高选择性,在10-3~10-6mol/L的浓度范围内响应斜率为53.3 mV/paAg ,检测下限为3.8×10-7mol/L,碱金属、碱土金属及过渡金属离子不干扰银的测定,电极具有较好的重现性和稳定性.该电极可作为Ag 准确滴定卤素阴离子和维生素B1药片中维生素B1含量的电位滴定指示电极,并用于水样中银离子含量的直接测定.     

利巴韦林含量的线性扫描极谱法测定

建立了用线性扫描极谱法测定药物中利巴韦林含量的新方法,在HAc-NaAc缓冲溶液中(pH=4.8),发现利巴韦林在-2.1V(vs SCE)产生一灵敏的极谱还原峰.该峰峰电流i p与利巴韦林浓度在5.0×10-6～6.0×10-4mol/L范围内,呈良好的线性关系(r=0.999 2,n=9).经11次平行测定,其相对标准偏差RSD为0.9%,平均回收率为99.45%.     

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