CTAB胶束溶液对正脂肪酸乙酯碱性水解反应的催化动力学行为研究

在20℃条件下，运用电导测定方法及非线性动力学模型进行数据处理，得到了在不同浓度十六烷基三甲基溴化胺(CTAB)胶束水溶液中正脂肪酸乙酯(甲酸乙酯，乙酸乙酯，丙酸乙酯，丁酸乙酯及正戊酸乙酯)碱性水解反应的速率常数．依据离子交换模型(PIE)理论讨论了在第一和第二临界胶束浓度(CMC)时，CTAB对正脂肪酸乙酯碱性水解反应速率的影响及规律性．     

固－液相转移催化合成1－氰基环丙烷甲酸乙酯

在固－液相转移催化条件下，以氟化钾浸渍的氧化铝作为强碱，合成了１－氰基环丙烷甲酸乙酯，并探讨了该反应的机理．     

甲酸乙酯和乙醇汽液相平衡的估算

用修正的UNIFAC模型对常压下甲酸乙酯和乙醇的汽液平衡进行估算,得到理论共沸组成为0.935(甲酸乙酯摩尔分数).与UNIFAC模型计算结果相比,修正的UNIFAC模型更接近实验值.常压下甲酸乙酯和乙醇存在共沸点,共沸温度为327.38K,不能用普通精馏进行分离.     

3-氨基-2-苯并呋喃甲酸乙酯合成方法的改进

对文献报道的3-氨基-2-苯并呋喃甲酸乙酯的合成方法作了改进，简化了操作方法，提高了产率．化合物结果与文献报道完全符合．     

N-(2,4-二甲苯基)亚胺基甲酸乙酯的合成研究

本文研究了在酸催化下,2,4—二甲基苯胺和原甲酸乙酯反应,合成N—(2,4—二甲苯基)亚胺基甲酸乙酯。通过提高反应温度,增加原甲酸乙酯对2,4—二甲苯胺的配比,以盐酸作催化剂,用常压代替减压,从反应混合物中及时蒸出生成的乙醇,使产品收率从文献报导的70%增加到90%以上。过量的原甲酸乙酯能够回收和继续使用。付产物N,N′—双(2,4—二甲苯基)甲脒和乙醇分别用于合成N—(2,4—二甲苯基)亚胺基甲酸乙酯和原甲酸乙酯。     

甲酸乙酯对土耳其扁谷盗的熏蒸作用

采用密闭熏蒸法研究了甲酸乙酯在不同条件下对土耳其扁谷盗卵、低龄幼虫、高龄幼虫、蛹和成虫的致死作用．在28 ℃条件下,以体积分数为0.040和0.045的药剂处理土耳其扁谷成虫12　h,其校正死亡率分别为88.633%和99.453%;以体积分数为0.035的药剂在15,18,21,24,27,30,33　℃下处理24　h,校正死亡率分别为84.367%,88.087%,92.376%,74.266%,63.252%,60.935%,58.775%,表明甲酸乙酯具有良好的速效性,且在相对低温时比在相对高温时熏蒸效果好.在20,25,30　℃条件下,熏蒸处理土耳其扁谷盗成虫24　h,其半致死体积分数LC50为0.014 31,0.017 335,0.021 073;处理48　h时则分别为0.012 828,0.015 446,0.020 068,质量浓度为30　g/m3的甲酸乙酯处理土耳其扁谷盗卵,低龄幼虫,高龄幼虫和蛹24　h,对应死亡率为93.372%,99.782%,96.638%,91.645%,表明甲酸乙酯对土耳其扁谷盗低龄幼虫熏蒸效果最好,蛹和卵对甲酸乙酯具较强的抗药性.     

香豆素-3-甲酸乙酯合成方法的改进

微波辐射下水杨醛和丙二酸二乙酯在六氢吡啶催化下于119W反应5分钟,以83．4％的产率得到香豆素-3-甲酸乙酯。和教材方法相比,微波法具有反应时间短、产率高、物耗低及污染物少等特点,体现了新兴技术的运用和化学实验绿色化的改革目标。     

氢化诺卜基腈及其衍生物的合成与结构表征

由氢化诺卜基溴在乙醇中与氰化钠回流反应,合成了氢化诺卜基腈,得率达90%以上.后者经水解制得氢化诺卜基甲酸,乙醇解得氢化诺卜基甲酸乙酯,经催化氢化制得了氢化诺卜基甲基胺.各产物经纯化后进行了红外光谱、核磁共振和质谱分析,表征了它们的结构.     

氯代甲酸乙酯与活性聚丁二烯基锂反应机理的研究

以有机锂为引发剂,丙酮、苯甲醛或1,1-二苯基乙烯为戴帽剂,氯代甲酸乙酯为终止剂,研究了氯代甲酸乙酯与不同端基阴离子活性聚丁二烯的反应机理.氯代甲酸乙酯与聚丁二烯基锂发生偶联反应,采用戴帽方法,可消除偶联反应,合成出端碳酸酯基和端酯基遥爪聚丁二烯.     

(4 S)-苯氧基-(S)-脯氨酸的合成

以光学活性的天然L-羟基脯氨酸为原料，通过氯甲酸乙酯／甲醇反应生成N—乙氧羰基—(4R)—羟基—(S)—脯氨酸甲酯，然后通过Mitsunobu反应在吡咯环4—位引入苯氧基，最后通过水解脱去保护基，合成了(4S)—苯氧基—(S)—脯氨酸．产物经核磁、元素分析鉴定．     

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