KBrO3--KBr紫外分光光度法测定痕量苯酚

研究了HCl溶液中KBrO3-KBr紫外分光光度法测定苯酚的条件.建立了测定痕量苯酚的新方法.结果表明,在0.6 mol/L HCl,4.6×10-5 mol/L KBrO3,5.1×10-4mol/L KBr,5.7×10-4mol/L KI溶液中测定苯酚,其线性范围为0～120 mg/L,表观摩尔吸光系数为4.58×104L@mo1-1@cm-1,Sandell灵敏度为0.001 9μg/cm2.本法用于废水中苯酚的测定,结果满意.     

非离子微乳液增敏4-AAP光度法测定废水中痕量的苯酚

在磷酸-磷酸二氢钾缓冲介质中,痕量苯酚对铁氰化钾氧化4-氨基安替比林（4-AAP）的反应有一定的催化作用.实验发现,OP/异戊醇/甲苯/水非离子型微乳液对上述反应有较强的增敏作用,因此建立了一种测定痕量苯酚的分光光度法.实验结果表明,溶液的最大吸收波长在520 nm,表观摩尔吸光系数为9.69×102L/（mol.cm）.该方法的检出限是0.2632μg/mL,相对标准偏差为2.3%,回收率为101.2%.该方法用于废水中痕量苯酚的测定,结果满意.     

分光光度法测定洋葱中微量锗

用苯芴酮—溴化十六烷基三甲胺分光光度法测定洋葱中的微量锗 ,不经萃取分离 ,有色溶液在 5 12 nm处比色。分析方法的线性范围为 0 .0 - 2 .5 μg/m L,获得较满意结果     

吸光光度法间接测定痕量苯酚

研究了用吸光光度法间接测定痕量苯酚的方法。在 KBrO_3和KBr溶液中,以淀粉-碘化钾为显色剂,最大吸收波长为590nm,线性范围为0.1～2.0mg/L,测定值的相对标准偏差为2.36％,平均回收率为101％。该方法应用于测定废水中苯酚,结果满意。     

阻抑溴酸钾氧化丁基罗丹明B褪色光度法测定痕量苯酚

用停流动力学分析技术研究了H2SO4介质中苯酚抑制BrO-3氧化丁基罗丹明B褪色的反应,并探讨了其反应机理;基于苯酚对该反应诱导期的影响作用,建立了停流-抑制动力学褪色光度法测定痕量苯酚的新方法.该方法测定苯酚的检出限为1.3×10-9 g/L,线性范围为0.3～15.0 μg/L,11次测定苯酚(5.0 μg/L)的相对标准偏差为2.1%;用于测定河水和工业废水样品中的痕量苯酚,结果满意.     

流动注射化学发光法测定苯酚

本文采用流动注射技术,研究了高锰酸钾-苯酚体系的化学发光行为,对影响化学发光强度的诸因素进行了实验和探讨,建立了化学发光法测定苯酚的新方法.方法的检出限为3×10-7g/mL线性范围为1.0×10-6~1.0×10-4g/mL.对4.0×10-6g/mL的苯酚进行11次平行测定,得方法的相对标准偏差为1.5%.方法用于废水中苯酚含量的测定,结果与分光光度法测得值一致.     

紫外可见分光光度法测定污水中间-硝基苯酚的含量

采用紫外可见分光光度法测定污水中间-硝基苯酚的含量,结果表明间-硝基苯酚在以去离子水为溶剂、最大吸收波长为272nm的条件下,浓度在2mg/L～10mg/L范围内线性关系良好,得到其线性方程为A=0.040 2C＋0.035 2,R2=0.999 8。结合线性回归方程可以计算出各地区污水中间-硝基苯酚的含量,并测得对各地区污水中间-硝基苯酚的平均回收率为97.7%,RSD小于0.39,由此说明采用紫外可见分光光度法测定各地区污水中间-硝基苯酚的含量具有操作简便,结果准确,灵敏度高的优点,在实际应用过程中可以做到降低检测成本,简化操作步骤,从而提高研究的工作效率。紫外可见分光光度法对各地区污水中间-硝基苯酚的含量测定,也为今后研究此类问题提供依据。     

紫外分光光度法测定废水中油的含量

介绍了利用紫外分光光度法测定废水中油的含量.选定波长为255 nm,对实验数据进行线性回归,列出了回归方程,标准偏差为1.91%,最低检测限为0.043 mg/L,精密度和灵敏度高,检测限低.所用溶剂为石油醚,溶解能力强,来源较广,毒性小.因此,利用紫外分光光度法测定废水中油的含量简单、快速,测定结果准确可靠.     

紫外分光光度法检测土壤-水溶液中百菌清分析方法的建立

探讨了紫外分光光度法测定土壤-水溶液中百菌清的方法,分别考察了离子强度和溶液的p H值对百菌清测定的影响,该方法测定百菌清在0.05~0.8 mg/L范围内线性良好,其工作曲线为y=0.229 2 x+0.003 1,相关系数R=0.999 1.平均加标回收率为86.34%~103.85%,RSD值在0.6%~1.06%之间(n=3),方法的检测限为0.013 4 mg/L.所建立的紫外分光光度法与气相色谱法测定结果无显著性差异.结果表明,紫外分光光度法操作简便快捷,干扰少,测定结果准确可靠,可用于土壤-水溶液中低浓度百菌清的测定.     

胶束毛细管电泳法测定焦化废水中苯酚

利用胶束毛细管电泳法建立了测定焦化废水中苯酚的方法.研究了检测波长、缓冲体系、缓冲液pH值和浓度、SDS浓度以及分离电压对苯酚测定的影响.研究表明测定苯酚的最适条件为：检测波长275 nm,40mmol/L硼砂-40 mmol/L SDS缓冲液（pH 9.5）,分离电压25 kV.苯酚检出限为4.614×10-3mg/L,线性范围为0.094~0.941 mg/L,相对标准偏差RSD（n=5）〈3%。该方法可高效快捷测定焦化废水中的苯酚含量.     

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.     

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the