SPME-HPLC联用分析环境水样中五种多环芳烃

应用固相微萃取与高效液相色谱联用技术(SPME-HPLC)分析环境水样中菲、蒽、苯并(α)蒽、苯并(k)萤蒽和苯并(α)芘等五种多环芳烃。对影响SPME的实验条件如萃取时间、萃取温度、离子强度、解吸方式、解吸溶剂、解吸时间以及HPLC条件进行了优化,建立了分析方法,并将其用于实际水样分析。方法的线性范围分别为0 03-20,0 01—20,0 06—5,0 3—12,0.15—10μg/L,检出限分别为0 009,0 004,0 018,0 090,0 045μg/L,相对标准偏差(RSD%,n=6)介于1 0%～4 5%,加标回收率在99 7%～112 9%之间。该方法适合于环境水样中多环芳烃混合物的分析,体现了SPME在样品前处理中快速、灵敏、简单、无溶剂的特点。     

水中林丹的固相微萃取与气相色谱耦合研究

介绍了一种改进的固相微萃取技术(SPME)、气相色谱-电子捕获检测器(GCLECD)联用测定水中林丹的新方法.该法将萃取了林丹的PDMS纤维用少量有机溶剂解吸,解吸后的有机溶剂进入气相色谱检测,从而实现固相微萃取与自动进样器的耦合.通过评价吸附时间、解吸时间、温度、pH等条件对萃取效率的影响,确定如下实验条件:吸附时间120 min、解吸时间60 min、室温(25℃).当林丹加标浓度为20 ng/mL时,该法与GC-ECD耦合后的回收率为82%,检测限为21 ng/L,相对标准偏差为0.8%,浓度-响应曲线在2.5～40 ng/mL时呈线性(R2=0.993,N=5).该法已应用到太湖水样中林丹的监测.     

改性TiO_2纳米管介质用于快速检测柴油机排放多环芳烃的研究

使用阳离子表面活性剂CTAB对二氧化钛纳米管阵列进行修饰作为固相微萃取(SPME)材料,对固相微萃取的参数如提取时间、解吸时间和解吸溶剂进行优化,用于检测船舶柴油机排放的非常规污染物多环芳烃.优化的SPME条件为:CTAB浓度为90 mg/L;有机溶剂为二氯甲烷;pH值为7;解吸液为二氯甲烷;解吸附时间为6 min.16种多环芳烃在浓度范围0.5~100μg/L之间呈良好的线性关系,相关系数均达到0.990以上,检测限达到0.001~0.005μg/L,样品加标回收率范围为80.1%~99.2%,日内精密度(n=6)的相对标准偏差范围在3.7%~9.1%之间.新方法的样品采集和预处理时间比传统方法节约90%,方法灵敏、准确,可以用于快速检测柴油机非常规排放.     

自动固相微萃取-气相色谱法检测水样中壬基酚

利用气相色谱仪器上的自动固相微萃取平台,建立了自动固相微萃取-气相色谱(SPME-GC)联用测定水样中壬基酚的分析方法。对SPME的条件如萃取纤维涂层、萃取时间、解吸时间、离子强度等条件进行了优化,并用于珠江水样和造纸工业废水等实际水样的分析。该方法的检测限为2.0μg/L,线性范围为5.0~100μg/L,线性相关系数为0.997 3,相对标准偏差(RSD)为3.3%(n=5),回收率为83.2%~106.4%。     

自制聚二甲基硅氧烷/二乙烯基苯固相微萃取膜富集水样中邻苯二甲酸酯类化合物

采用湿法制膜技术制备了聚二甲基硅氧烷/二乙烯基苯(PDMS/DVB)新型固相微萃取膜,以扫描电镜、红外光谱和热重分析等手段对自制膜的性能进行表征.考察了吸附条件、解吸条件的影响,用于珠江水和湖水中邻苯二甲酸酯类化合物的分离富集.珠江水样检出3种邻苯二甲酸酯类化合物,湖水样检出5种邻苯二甲酸酯类化合物,含量在41.17～119.49μg/L之间,回收率79.6%～112.4%,RSD 12.5%～23.8%.与固相微萃取纤维相比,固相微萃取膜制作成本低、使用方便、吸附容量大,是一种有发展前景的样品前处理新技术.     

固相微萃取——高效液相色谱联用测定水样中的痕量苯并（k）荧蒽

研究了固相微萃取(SPME)——高效液相色谱(HPLC)联用测定水样中痕量苯并(k)荧蒽的的分析方法。对SPME的条件如萃取时间、萃取温度、离子强度、解吸溶剂、解吸时间和HPLC条件进行了优化，建立了SPME-HPLC联用分析水样中痕量苯并(k)荧蒽的方法，并用于自来水、雨水和纯净水等实际水样的分析。SPME优化的条件为室温、搅拌速度l100r／min、萃取时间30min、甲醇解吸溶剂、解吸时间2min。HPLC的条件为C18反相色谱拄、甲醇流动相、流速为1mL/min、紫外检测器、波长244nm，以峰高为测量信号。方法的线性范围为0—8．00μg/L，检出限为0．014μg/L，相对标准偏差(n＝6)为6．7％，回收率为82．0％-104．2％。该方法适合于水样中痕量苯并(k)荧蒽的分析。     

固相微萃取/气相色谱-质谱联用技术在有机磷酸三酯阻燃剂土壤吸附分析中的应用

以3种常用且极性相差较大的有机磷酸三酯阻燃剂(OPFRs)作为研究对象,采用固相微萃取/气相色谱-质谱(SPME/GC-MS)联用技术建立了一种适用于研究OPFRs土壤吸附的分析方法:优化固相微萃取的萃取条件——取样体积为7mL,萃取时间为30min,解吸温度和时间分别为270℃和5min;分析测定过程中导致空白值升高的干扰因素;针对不同类型的土壤分别绘制标准曲线。利用已建立的SPME/GC-MS法对3种OPFRs在不同类型土壤中的吸附程度进行了初步评估,结果表明:3种OPFRs在试验土壤中的吸附率为27%~69%,吸附程度随着OPFRs极性的减弱以及土壤有机质含量的增加而增加。该方法具有操作简单,分析速度快,准确度、灵敏度和精密度均能满足定量测试要求,空白干扰小以及易于普及等特点。     

不锈钢纤维支载SiO_2/PDMS-MWNTs膜固相微萃取测定水样中三苯含量

采用sol-gel法首次制备了不锈钢纤维支载SiO2/聚二甲基硅氧烷-多壁碳纳米管复合膜(SiO2/PDMS-MWNTs)固相微萃取(SPME)新型萃取头,并与气相色谱联用,检测了环境样品中的痕量苯、甲苯和二甲苯(BTX),文中研究了SiO2/PDMS-MWNTs复合膜的制备条件,并探讨和优化了测定痕量BTX的SPME条件,结果表明,最佳萃取条件:萃取温度为40℃,萃取时间为20 min,搅拌速度为300 r min-1,解吸时间为3 min,在最佳条件下,本法检出限为0.01-0.02μg mL-1,线性范围为1-1000μg mL-1,样品回收率为92.2-103.4%,比较商用萃取头,SiO2/PDMS-MWNTs复合膜萃取头具有稳定,寿命长,萃取效率高等特点,     

几种新技术在茶叶农药残留分析样品前处理中的应用

介绍了几种发展较快的样品前处理技术:如固相微萃取(SPME)、微波辅助萃取(MAE)、加速溶剂萃取(ASE)、超临界流体萃取(SFE)、凝胶渗透色谱(GPC)、基质固相分散技术(MSPD)的原理及其在茶叶农药残留分析中的应用情况.     

自制固相微萃取涂层同时测定水中的多环芳烃和酞酸酯

采用自制的固相微萃取涂层, 通过顶空固相微萃取与气相色谱法（HS SPME GC）联用测定水中的多环芳烃(PAHs)和酞酸酯(PAEs), 并优化了固相微
萃取条件. 实验结果表明： 当样品中加入4 g NaCl, 并以一定速度搅拌, 70 ℃顶空萃取50 min, 280 ℃解吸5 min时, 其检测限为0.005～0.1 μg/L, 线性范围为1～100 μg/L. 使用该方法检测武汉市东湖水样的加标回收率为72.0%～116.3%, 相对标准偏差(RSD)为5.2%～8.5%.     

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-