离子色谱法测定饮用水中痕量卤乙酸

本文建立了一种无需样品前处理,直接大体积进样,电导检测饮用水中痕量卤乙酸的离子色谱新方法。分析柱为Dionex IonPac As9阴离子交换柱,GP40在线产生NaCO3淋洗液,等浓度泵作梯度淋洗。该方法对卤乙酸的检出限为:二氯乙酸30μg/L、三氯乙酸40μg/L。将该方法用于济南市自来水卤乙酸的检测,实际样品的加标回收率:二氯乙酸90%～109%、三氯乙酸92%～106%。     

吹扫捕集气质联用法检测供水管网中消毒副产物——三氯乙醛

建立了供水管网中三氯乙醛的吹扫捕集/GC-MS检测方法.吹扫捕集与碱化反应同时进行,三氯乙醛完全快速转化为三氯甲烷,通过检测加碱前后管网水中三氯甲烷的含量,间接计算出管网水中三氯乙醛的含量.方法的线性范围为0～20μg/L,检出限为0.16μg/L,相对标准偏差<5%,平均回收率为90%～100%.     

气相色谱法测定水环境中甲苯及硝基苯类化合物含量

采用正己烷萃取,气相色谱法测定水中甲苯、硝基苯、邻硝基甲苯、间硝基甲苯、对硝基甲苯。方法在6.25~100μg/L范围内线性良好,检出限为0.2~0.25μg/L。标准溶液平行测定的RSD≤10.0%,加标回收率分别为80%~114%。方法简便快速,可用于实际样品的检测。     

饮用水中三卤甲烷的顶空-气相色谱-质谱联用检测方法及健康风险评估

利用顶空-气相色谱-质谱联用仪建立了选择离子扫描方法(SIM)用以检测饮用水中三卤甲烷含量,并针对顶空条件进行优化以提高检测的灵敏度及效率.将该方法应用于N市4个小区2016年6—8月饮用水中三卤甲烷含量的检测;同时基于美国环境保护署(EPA)推荐的健康风险评价模型对经口暴露途径的三卤甲烷的致癌风险进行评估.研究结果表明,该方法在2～100μg/L范围内可以准确高效地检测饮用水中的三卤甲烷.对三卤甲烷含量的致癌风险评估发现, N市饮用水中三卤甲烷的致癌风险计算值为2.74×10~(-5),在10~(-4)～10~(-6)之间,提示存在致癌风险,但在可接受的风险水平,其中CHCl_2Br对总致癌风险贡献最大.该研究对N市饮用水中消毒副产物的健康风险有了进一步了解,可为今后开展饮用水安全评价提供参考.     

顶空气相色谱法测定水中乙醛、丙烯醛、丙烯腈和吡啶

建立水中乙醛、丙烯醛、丙烯腈和吡啶的顶空气相色谱测定方法,经顶空进样,用HP-INNOWAX毛细管色谱柱程序升温分离,FID检测,以保留时间定性,外标法定量。水中乙醛、丙烯醛、丙烯腈和吡啶的浓度范围分别在16.0~800μg/L、16.0~800μg/L、15.4~768μg/L、80.0~4 000μg/L时,回归曲线相关系数为0.999 7、0.998 9、0.999 9和0.997 9,检出限分别为2.6、2.7、2.0和4.4μg/L。乙醛、丙烯醛、丙烯腈和吡啶分别在16.0μg/L、16.0μg/L、15.4μg/L、80.0μg/L浓度时,7次平行测定结果的相对标准差分别为5.3%、5.6%、4.3%和1.7%,样品加标回收率乙醛为92.6%、丙烯醛为92.8%、丙烯腈为99.6%和吡啶为102%。实验结果表明,顶空气相色谱法在相关系数、检出限、相对标准偏差、回收率等各方面均满足地表水环境质量标准要求,而且顶空气相色谱法前处理简单,无需使用有机溶剂,简便、快速、准确、重现性好,适合各种水体中乙醛、丙烯醛、丙烯腈和吡啶的同时测定。     

氢化物发生原子荧光法测定饮用水中的砷和硒

建立饮用水中砷和硒同测的氢化物发生-原子荧光法测定方法。选择最佳的仪器条件,在体积分数为10%的盐酸介质中,砷和硒线性范围为0~40.00μg/L,砷和硒的检出限分别为0.06μg/L和0.04μg/L,加标回收率为97.8%~106.6%,RSD(n=10)2.9%。此方法操作简便,灵敏度高,适用于饮用水中砷和硒的测定。     

液相色谱-串联质谱法检测水中痕量微囊藻毒素-LR和微囊藻毒素-RR

建立直接进样测定饮用水和水源水中的微囊藻毒素(MC-RR、MC-LR)的液相色谱-质谱分析方法。水样过0.22,μm PTFE滤膜,用Waters Xevo TQD超高效液相色谱串联质谱仪分析检测,采用色谱柱Waters BEH C81.7,μm、2.1,mm×50,mm进行分离。采用电喷雾电离正离子模式(ESI+),以外标法定量分析。MC-RR的浓度在0.1~2.0,μg/L,MC-LR的浓度在0.5~10.0,μg/L范围时,它们的线性关系r≥0.999,0。微囊藻毒素-LR、微囊藻毒素-RR在水中进行高、中、低3个水平的添加,各组分相对标准偏差(RSD)为4.18%,~8.69%,,平均回收率在82%,~91%,之间,最低检测下限(LOD)MC-RR为0.04μg/L,MC-LR为0.09,μg/L。此方法简便、快捷、准确,具有较好的实用价值。     

硫酸浓度对纳米级SO2-4/TiO2固体超强酸的影响

用锐钛型纳米TiO2制备了纳米级SO2-4/TiO2固体超强酸,分析了硫酸浓度不同时其比表面积、失重率、红外光谱及催化活性的不同.当硫酸浓度为1.0mol/L时,它在450～900℃的失重率为3.3%,比表面积为105.2 m2/g,对乙酸和丁醇酯化反应的酯化率达到98.4%.玻璃球负载纳米级SO2-4/TiO2固体超强酸的重复使用性能好,在乙酸和丁醇的酯化反应中重复使用9次后的酯化率才由初次的99.3%变为84.9%.     

顶空固相微萃取-气相色谱法测定水中芳香胺类化合物

建立了顶空固相微萃取-气相色谱法(HS-SPME-GC)测定水中芳香胺类化合物的方法.采用溶胶-凝胶法,加入自制的离子液体键合固相微萃取涂层,对萃取温度、萃取时间、pH值、离子强度等实验条件进行了优化.方法的检测限为0.5～5μg/L,线性范围在10～1000μg/L,相对标准偏差(RSD)不大于8.6%.对东湖水样进行了测定,未检测到3种芳香胺类化合物,其回收率为87.5%～99.9%.     

CdTe/CdS量子点荧光探针测定痕量汞(Ⅱ)

在水溶液中合成巯基乙酸修饰的CdTe/CdS量子点(QDs),再基于Hg2+与CdTe/CdS量子点的荧光猝灭作用,建立用CdTe/CdS量子点作为荧光探针检测微量汞的新方法,并用该方法测定水中汞的含量。研究表明,pH值为6.24的磷酸缓冲溶液中,量子点浓度为3.75×10-4mol/L时,Hg2+离子浓度在2.3～150μg/L范围与CdTe/CdS量子点荧光猝灭强度呈良好的线性关系,相关系数为0.9985,检出限为0.87μg/L,回收率为99.0%～107.5%。该方法检测效果好,可用于实际样品分析。     

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-