On Lexicographical Treatment of Discourse Markers in E-C Bilingual Learner’s Dictionaries

话语标记语在英语为母语的人群中的使用频率非常高，是英语学习者必须重点学习掌握的一种词汇类型。随着话语分析和对话语标记语研究的不断深入，双语学习词典也应该相应地提高对话语标记语这种词汇类型的描写，以对英语学习者学习这种特殊的词汇类型作出应有的指导。然而，到目前为止，词典编纂者们对话语标记语这种词汇类型的关注相当有限，故本研究可看成是弥补这方面的缺憾的一次尝试。 本研究围绕如何改进话语标记语在英汉学习词典中的处理这个问题而展开，尝试将语言学界对话语标记语的研究观点和成果运用到英汉学习词典的词条处理中，以期英语学习者能更好、更系统地学习这种词汇类型。 为了达到研究目标，本研究介绍了该研究领域的术...Discourse markers (DMs), which are used very frequently by native speakers of English, are an important group of lexical elements that deserve close attention in English language learning. With the deepening of discourse analysis and DM study, bilingual learner’s dictionaries (BLDs) should accordingly improve the description of DMs, to provide sufficient guidance on the usage of this group of lexi...学位：文学硕士院系专业：外文学院英语语言文学系_英语语言文学学号：1202006115033

Expression of recombinant hARRG cDNA in E.coli and purification of hARRG protein

目的　构建含重组人类抗砷相关基因 (humanarsenicresistencerelatedgene ,hARRG)的表达载体 ,诱导其在转化菌表达 ,分离纯化表达蛋白 ,研究该蛋白质的理化性质、抗砷功能和免疫活性 ,深入研究人类对砷化物的抵抗作用。方法　将hARRGcDNA开放阅读框亚克隆到原核表达载体Pet11C中 ,用异丙基 - β -D -硫代半乳糖苷 (IPTG)诱导表达蛋白质 ,利用阴离子交换柱Sepharose纯化蛋白质 ,SDS -PAGE胶电泳观察结果。 结果　将hARRGcDNA成功亚克隆到原核表达载体Pet11C中 ,并成功在大肠杆菌中表达 ,表达的hARRG蛋白占菌体蛋白的 5 %左右 ,该蛋白质被分离纯化。结论　原核表达载体Pet11C可以在大肠杆菌中表达hARRGcDNA ,可用阴离子交换柱Sepharose纯化抗砷相关蛋白质Objective To construct expression vector of the recombinant human arsenic resistance related gene (hARRG),induce its expression in DE\-3 and isolate and purify expression product,for studying the physiochemistry characteristic,function and immune activity of the protein,and further researching the arsenic resistant effects of human.Methods hARRG cDNA was subcloned into prokaryotic expression vector Pet11C.The recombinant protein expression was induced by IPTG,then,the protein was purified by anions Ion-exchange column Sepharose and examined by SDS-PAGE gel.Results hARRG cDNA was successfully subcloned into prokaryotic expression vector Pet11C and expressed in E.coli and the protein was purified by anions Ion-exchange column successfully.Conclusion Pet11C excpression vector containing hARRG cDNA wassuccessfully constructed,the cell DE\-3 transformed with expression vector capable of expression the gene and a hARRG protein could be purified by anions Ion-exchange column Sepharose.国家自然科学基金资助项目 (30 0 60 0 74

Association of Gln223Arg Polymorphism in Lepr Gene with Type 2 Diabetes in Northern Chinese HaM Population

目的探讨瘦素受体(Lepr)基因第6外显子Gln223Arg多态性与中国北方人2型糖尿病(T2DM)的关系。方法应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法鉴定了相互间无亲缘关系且具有完整临床资料的728例中国北方汉族人的Lepr基因Gln223Arg多态性的基因型(其中包括有糖尿病家族史的T2DM患者333例,非糖尿病健康对照395例)。结果 Lepr基因Gln223Arg多态性的基因型频率和等位基因频率在T2DM组和正常对照组中的分布存在显著性差异(P&lt;0.05)。多因素Logistic回归分析结果显示,进行年龄、性别、BMI和腰围等因素调整后,GG基因型的携带仍然能够增加T2DM的患病风险。结论 Lepr基因第6外显子Gln223Arg多态性与中国北方人T2DM的易感性相关联。</p

TiO_2表面光催化基元过程

在过去的几十年里,得益于二氧化钛（TiO2）作为光催化剂在光催化分解水、污染物降解方面的潜在应用,人们对TiO2光催化剂的开发、改良以及TiO2表面光催化机理的基础研究方面都投入了巨大的精力。因此,在超高真空环境下,利用不同的实验和理论方法,人们对TiO2表面（特别是金红石TiO2（110）表面）的热催化和光催化过程进行了大量的研究,以此来获得上述重要反应中的一些机理性的信息。本文中,将从TiO2的物质结构以及电子结构开始,然后着重介绍TiO2表面光生电荷（电子和空穴）的传输、捕获以及电子转移动力学方面的进展。在此基础上,总结了甲醇在金红石TiO2（110）、TiO2（011）以及锐钛矿TiO2（101）表面光化学基元反应过程的一些实验结果。这些结果不仅能增进我们对表面光催化基元过程的认识,同时也能激励我们进一步去研究表面光催化基元过程。最后,基于现有光化学实验结果,简短地讨论了我们对光催化反应机理的一点看法,并提出了一个可能的光催化模型,这可以引起人们对光催化反应机理更全面的思考

甲醇在TiO2(110)表面的光化学

Titanium dioxide is one of the most important materials for real world applications in chemical catalysis[1-4]. Photocatalysis by TiO2, especially its application in water splitting[1], has attracted much attention. It has been reported that pure TiO2 is minimally active for water splitting to produce hydrogen[5], while the same catalyst is much more active for hydrogen production from water–methanol mixture[6]. Clearly, the chemistry of methanol on TiO2 has played a crucial role in this process. Therefore, it is essential to understand the photocatalytic chemistry of methanol on TiO2, which could potentially provide clues for developing new efficient photocatalysts for water splitting. Here, we report the first clear evidence of photocatalyzed splitting of methanol on TiO2 derived from time-dependent two-photon photoemission (TD-2PPE) results in combination with scanning tunneling microscopy (STM). STM tip induced molecular manipulation before and after UV light irradiation clearly reveals photocatalytic bond cleavage, which occurs only at Ti4+ surface sites. TD-2PPE reveals that the kinetics of methanol photodissociation can be well described by the fractal-like kinetics model, however, the physical nature of the fractal parameters is not clear immediately. Further studies showed that the photocatalyzed dissociation rate of methanol on reduced TiO2(110) is more than an order of magnitude faster than on the stoichiometric surface, indicating the surface defects could accelerate the photocatalysis process of methanol on TiO2(110) in a significant way, probably by lowering the reaction barrier.Titanium dioxide is one of the most important materials for real world applications in chemical catalysis[1-4]. Photocatalysis by TiO2, especially its application in water splitting[1], has attracted much attention. It has been reported that pure TiO2 is minimally active for water splitting to produce hydrogen[5], while the same catalyst is much more active for hydrogen production from water–methanol mixture[6]. Clearly, the chemistry of methanol on TiO2 has played a crucial role in this process. Therefore, it is essential to understand the photocatalytic chemistry of methanol on TiO2, which could potentially provide clues for developing new efficient photocatalysts for water splitting. Here, we report the first clear evidence of photocatalyzed splitting of methanol on TiO2 derived from time-dependent two-photon photoemission (TD-2PPE) results in combination with scanning tunneling microscopy (STM). STM tip induced molecular manipulation before and after UV light irradiation clearly reveals photocatalytic bond cleavage, which occurs only at Ti4+ surface sites. TD-2PPE reveals that the kinetics of methanol photodissociation can be well described by the fractal-like kinetics model, however, the physical nature of the fractal parameters is not clear immediately. Further studies showed that the photocatalyzed dissociation rate of methanol on reduced TiO2(110) is more than an order of magnitude faster than on the stoichiometric surface, indicating the surface defects could accelerate the photocatalysis process of methanol on TiO2(110) in a significant way, probably by lowering the reaction barrier