光稳定剂间苯二酚单苯甲酸酯的合成

研究了以苯甲酰氯和间苯二酚为原料、液碱为除酸剂,酯化合成然后精制得间苯二酚单苯甲酸酯的工艺.研究了酯化反应中温度、物料配比、pH、间苯二酚水溶液的浓度和反应时间等条件对反应的影响,获得了较佳的酯化工艺条件:苯甲酰氯与间苯二酚的摩尔比为1.15∶1;pH值为7.5;反应温度为25℃;反应时间为1.5 h;间苯二酚溶液的质量分数为10%.酯化反应收率为88.6%.考察了结晶溶剂配比、温度对产品质量和收率的影响,经实验评估得到了较佳的结晶工艺条件:结晶溶剂甲苯的体积(/mL)与初产物的质量(/g)之比为2.5∶1,结晶温度为30℃,结晶收率为95.0%.优化工艺条件下产品的总收率为84.2%.     

N-乙烯基己内酰胺的合成及放大

以己内酰胺和乙炔为原料,己内酰胺与叔丁醇钾制得的己内酰胺钾盐为催化剂,对叔丁基邻苯二酚为阻聚剂合成N-乙烯基己内酰胺.考察催化剂用量、阻聚剂用量、搅拌速率、反应温度及反应时间对产品收率的影响.用红外光谱仪、核磁共振波谱和质谱对产品结构进行表征.并依据小试条件进行放大实验.结果表明:在催化剂用量为3.5%,阻聚剂用量为0.04%(以己内酰胺质量计),搅拌速率200r/min,温度90℃,反应8h的优化工艺条件下,产品收率为75.4%,质量分数达99.87%.放大40倍后,产品收率为74.6%.     

威兰胶发酵液脱除菌体的酶解工艺研究

为研究威兰胶发酵液的菌体去除工艺与菌体脱除效果之间的关系,采用单因素优化法,考察了反应温度、反应体系pH值、溶菌酶用量和搅拌速率等操作条件对菌体去除率的影响。试验结果确定的菌体脱除工艺为:反应温度为40℃,反应体系pH为6.5,溶菌酶加入量为1.0%,搅拌速率为600 r/min。在此条件下,威兰胶发酵液中蛋白质的去除率为89.2%。经醇沉工艺提取后,威兰胶产品中菌体去除率为93.6%。     

极端微生物处理制浆黑液的影响因素

利用黑液塘底泥中的极端微生物对制浆黑液进行了厌氧生物处理,并研究了污泥投加量、黑液浓度、pH和温度等工艺条件对生物降解反应的影响.结果表明:温度为30～35℃,pH6.5～7.2,V黑液∶V污泥=2∶1的厌氧条件下,制浆黑液的生化降解速率较快,有机物的去除率较高.此外,黑液中糖醛酸的生化降解反应适宜在高温弱酸(T＞50℃,pH＜6)的环境中进行,而溶液中部分大分子木质素则在反应过程中发生了降解.     

羟基磷灰石负载Ru催化氨硼烷产氢性能研究

采用浸渍-还原法制备了Ru/羟基磷灰石(HAP)催化剂,并考察了Ru负载量、还原剂硼氢化钠的用量、还原温度以及反应条件对催化剂Ru/HAP催化BH₃NH₃水解产氢的影响.结果表明:当Ru的负载质量分数为0.3%、Ru与还原剂硼氢化钠的物质的量比为1.0:2.2、还原温度为303 K时,Ru/HAP催化剂催化BH₃NH₃水解产氢的转化频率T_OF为125 mol H₂·mol^-1Ru·min^-1.当搅拌转速为450 r·min^-1时,外扩散限制消除,产氢速率最大.产氢速率与催化剂浓度成正比,氨硼烷水解产氢反应由催化剂界面反应控制,Ru/HAP催化剂催化BH₃NH₃水解产氢反应对催化剂浓度反应级数为0.8.随着反应温度的升高,氨硼烷产氢速率系数增大,副产物偏硼酸钠越易从催化剂表面脱附,产氢速率逐渐增大.反应动力学计算表明Ru/HAP催化剂催化BH₃NH₃水解产氢反应对氨硼烷浓度为0级反应,活化能为44 kJ·mol^-1.     

偏钛酸催化水解环氧环己烷制备反-1,2-环己二醇

采用固体偏钛酸为催化剂,催化水解环氧环己烷制备反-1,2-环己二醇,考察搅拌速率、反应时间、反应温度、物料摩尔比、催化剂的量及催化剂的重复性对水解反应的影响,并通过数字熔点测试仪和傅里叶变换红外光谱仪(FT-IR)对产物进行表征。结果表明:在搅拌速度为350 r/min,反应时间为1 h,反应温度为80℃,环氧环己烷与水的摩尔比为1∶10,催化剂用量为1.8%时,产物的熔点为102.9~103.0℃,反-1,2-环己二醇的收率为98%左右。在优化条件下,催化剂重复使用5次,反-1,2-环己二醇的收率未有明显降低。     

采用相转移催化氧化法脱除焦化苯中噻吩的研究

以模拟焦化纯苯为研究对象,以四丁基溴化铵(TBAB)为相转移催化剂,采用相转移技术,探讨相转移催化(PTC)氧化法脱除焦化纯苯中噻吩的工艺条件.结果表明,加入TBAB改善了两相间的传质,有效增强了氧化脱硫过程的速率.于反应温度70 ℃、反应时间45 min、水相中TBAB含量为0.2%、H2O2含量为16%、甲酸含量为8%、搅拌速率为400 r/min、剂苯比为3:10等操作条件下反应时,噻吩脱除率可达到89%以上.     

磷钼酸季铵盐催化柴油氧化脱硫研究

以十八烷基三甲基磷钼酸铵作催化剂、H2O2作氧化剂,对模型油和直馏柴油进行了氧化脱硫研究.结果表明,相同反应条件下,以磷钼酸季铵盐作催化剂时,二苯并噻吩(DBT)和苯并噻吩(BT)的脱除率比磷钼酸作催化剂分别提高了5.3倍和2.4倍;在70℃下反应2.5h,DBT、BT的脱除率分别达到100%和40.5%;动力学研究表明,DBT、BT的催化氧化反应皆符合表观一级动力学规律,其活化能分别为22.5kJ/mol和62.4kJ/mol;各反应条件对直馏柴油脱硫率的影响大小顺序为:催化剂用量＞反应时间＞氧化剂用量＞反应温度;在m(催化剂)/m(柴油)=1.8%、V(H2O2)/V(柴油)=2.5%、反应温度70℃、反应时间3h条件下,柴油的脱硫率达 88.7% ,收得率不低于99%.     

生物质能源开发——Ⅳ.泥炭的催化水解法

以半纤维素含量较高的泥炭为原料,在常压和加压(200℃左右的水蒸汽压)条件下,研究了水解法中反应时间、液固比、反应温度、酸浓度、催化剂等工艺条件对糖化率的影响。并比较了一步法和二步法的转化率。实验结果表明:可用常压一步法水解。其工艺条件为:泥炭粒度100目,反应温度100℃,盐酸浓度1.0～1.5%,液固比10.5～12.0,反应时间80～100min。添加催化剂能提高水解反应速度,FeCl_3有较高的催化活性。在上述条件下有近70%的可水解物水解为还原糖。水解后的残渣可以用于气化。     

环丙烷甲酸的相转移催化合成

以γ-丁内酯和异丙醇为主要原科,经亚硫酰氯氯代开环,再经固/液相转移催化(PTC)环合得环丙烷甲酸异丙酯(Ⅰ),最后经液/液PTC水解、中和制备环丙烷甲酸(Ⅱ).比较了不同相转移催化剂(PTCs)对化合物Ⅰ水解的催化能力,结果表明PTCs能显著加快化合物Ⅰ的水解速率.不同的PTCs的催化能力大小为BTEAC＞BTMAC＞CTMAB＞TBAB.最佳反应条件为化合物ⅠNaOH=12(摩尔比),BTEAC1.5%(mol),回流反应2h.此条件下化合物Ⅱ的产率为83.7%,总收率为72.7%.     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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