用偶氮氯磷—Ⅲ光度法测定水体中微量镁

水中微量镁,可用偶氮氯膦Ⅲ光度法快速、灵敏地进行测定。方法选用pH7.0的硼酸—氢氧化钾缓冲溶液,络合物最大吸收波长670nm,比尔定律适用范围0—0.48μg/ml。大量的钙,可用EGTA掩蔽,其它离子无干扰。水样实际分析结果和EDTA络合滴定法完全一致。     

流动注射分光光度法同时快速测定水泥及其原材料中高低含量的钙和镁

本文提出用流动注射光度法测定水泥及其原材料中高低含量的钙、镁。以EGTA标准溶液掩蔽高钙含量样品中的部份钙,并将其掩蔽部份加入结果计算;以缓冲剂氨—氯化铵和CTMAB退色的显色剂二甲酚橙的混和液为载流;于570,590nm处同时测定钙,镁络合物的吸光系数和样品吸光度,通过联立方程组求解结果。同时快速测定了样品中从高到低含量的钙和镁。进样频率为120样/小时;样品测定的查对百分偏差为钙(0.24％～3％),镁12.6～4％)(视样品种类和含量高低而定)。     

线性回归K系数分析法同时测定Ca(Ⅱ)和Mg(Ⅱ)

以酸性铬蓝K为显色剂，在20℃左右，pH为10～11时，经约10min的反应，其与Ca2^ 、Mg2^ 的生成稳定的1：1的配合物。采用Visual Basic编程处理，用线性回归方法同时确定K系数法中的系数K及工作曲线的斜率。测镁的波长组合为512～470nm，测钙的波长组合为541—528nm，由于所求得的K值和工作曲线的斜率均来自混合溶液本身，在样品中同时测定Ca^2 和Mg^2 离子的浓度时，即使在吸收曲线重叠严重、加和性也较差的情况下，钙、镁加入回收率约99．7％～10．8％，无需分离或加掩蔽试剂便可获得可靠的分析结果，方法简便易行。     

多波长数据线性回归光度法同时测定钙和镁

本文研究了酸性铬蓝K体系用于同时测定钙和慎的显色条件，借助多波长线性回归法处理数据，提出光度测定钙和镁的简便方法，免去了分离手续。应用于三个水样中钙、镁含量的测定，结果满意。     

双波长分光光度法同时测定环境水样中钙、镁

本文讨论了采用双波长分光光法同时测定环境水样中钙和镁。     

以长分光光度法同时测定环境水样中钙,镁

本文讨论了采用双波长分光光法同时测定环境水样中钙和镁。     

分光光度法同时测定海带中钙镁的含量

研究了以酸性铬蓝K为显色剂,同时测定海带中钙镁的方法.在pH=10~10.5的缓冲溶液中,络合物的最大吸收波长为:钙离子496 nm,镁离子506 nm.钙离子含量在0~6.00×10-5mol.L-1,镁离子含量在0~5.60×1 0-5mol.L-1范围内符合朗伯-比耳定律.经用本方法测定海带样品证明:每克干海带含钙量9.59 mg、含镁量1.41 mg.研究结果为进一步开发海带产品的医用价值提供了参考依据.     

ICP-AES法测定湿法磷酸中铝镁铁

建立了电感耦合等离子体—原子发射光谱法(ICP-AES)快速、准确并同时测定湿法磷酸中的铝、镁和铁,选定灵敏度较高的特征谱线作为分析线,优化仪器工作参数,无需使用磷酸配制标准工作溶液即可消除基体效应对测定结果的影响。在光谱仪处于最佳分析条件下,选定波长分别为396.156 nm、279.077 nm、238.204 nm的特征谱线作为本方法中元素铝、镁和铁的分析线。利用方法同时测定湿法磷酸中铝、镁和铁金属元素含量,检出限分别为0.0013μg/mL、0.0022μg/mL、0.0054μg/mL,铝、镁和铁测定结果的相对标准偏差(RSD)分别为1.5~6.5%、1.8~5.3%、2.5~8.0%,各项加标回收率为96.9%~106.2%、92.5%~104.0%、97.0%~105.5%。同时与标准加入法进行对比实验,分析结果基本吻合,铝、镁和铁的相对偏差(SD)分别≤3.85%、2.84%、2.63%,验证方法的准确性,能够满足科研及企业日常生产对湿法磷酸中铝、镁和铁一次性测定的需要。     

用钙离子选择电极电位滴定测胆汁中总钙和总镁含量

胆结石是外科常见病,钙和镁在胆石形成中有重要的作用。为探索胆石的成因和溶石的途径,需要测定胆汁中钙和镁的含量。关于胆汁中离子钙的测定,上次我们作了报导。对总钙测定,国内目前常用EDTA络合滴定法,因指示剂变色受胆汁颜色干扰等原因,精确度和准确度均较差。本文介绍用钙离子选择电极作指示电极,在pH 9—10氨性缓冲液中用EGTA作滴定剂测胆汁中总钙和EDTA作滴定剂测胆汁中总钙和总镁的合量,从两者之     

多波长数据线性回归分光光度法同时测定微量钙和镁

文章采用多波长数据线性回归法，以酸性格兰Ｋ与钙、镁的显色体系同时测定钙和镁．应用氢氧化物及硫化物沉淀分离法有效地消除了常见元素对测定的干扰．将此法用于自来水样分析，所得结果满意．     

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-