Preparation, Characterization and Surface Reserach of Supported PtCux and PtSnx Bimetallic Nanocatalysts

Pt催化剂是一类高效、稳定的催化剂，但Pt资源短缺且价格昂贵，限制了Pt的广泛商业化应用。Pt基双组份催化剂（Pt-Cu，Pt-Sn，Pt-Fe等）大大减少了Pt的用量，是很有前景的替代者，被广泛应用于多相催化，电催化，燃料电池等各个领域。第二组分的添加使Pt基催化剂表现出更高的活性、选择性及稳定性。 多相催化反应几乎总是在催化剂表面发生，催化剂的表面原子组成和结构是影响其催化性能的关键因素。本论文工作采用准原位X-射线光电子能谱（XPS）和高灵敏度低能离子散射谱（HS-LEIS）对体相组分确定的负载型PtCux和PtSnx催化剂进行表征，探究催化剂的表面性质、金属间的相互作用、表面组成与体...Pt catalysts are a kind of high efficient and stable catalysts. Its scarcity and high cost limit its wide application. Recently, Pt based bimetallic catalysts (Pt-Cu, Pt-Sn, Pt-Fe etc.), which can greatly reduce the amount of Pt, have been promising candidates of pure Pt widely used in various fields like hetergeneous catalysis, electrocatalysis and fuel cells. Owing to alloy effect, Pt bimetallic...学位：理学硕士院系专业：化学化工学院_物理化学学号：2052014115157

Using Elasticsearch to Rebuild Library's Intrawebsite Search Engine

由于云搜索服务的灵活度和稳定性无法满足需求,厦门大学图书馆决定应用ElASTICSEArCH重构站内搜索。通过环境部署、索引配置、数据导入、索引错误处理等步骤,厦门大学图书馆成功实现了基于ElASTICSEArCH的站内搜索,且在功能、界面等方面有所改进。据此进一步提出,ElASTICSEArCH未来可应用于大数据环境,成为数字图书馆的私有云搜索引擎。Ximen University Library decides to use Elasticsearch to rebuild intrawebsite search,because the flexibility and stability of cloud search service cannot keep up demand.Xiamen University Library successfully achieves Elasticsearch-based intrawebsite search by taking the steps of environment arrangement,index configuration,data importing,index error handling and so on,furthermore the function and the interface are improved to a certain degree.At last,the paper hereby points out that Elasticsearch can be applied in the environment of big data,and will become private cloud search engine of digital library

化工专业本科毕业生就业质量分析与就业服务研究——以厦门大学化工专业2011-2016届本科毕业生为例

近年来大学生就业形势严峻,如何提高大学生的就业质量成为就业服务工作的重点难点问题。本文以厦门大学化工专业为例,分析了该专业连续6届本科毕业生的就业质量,并结合实际工作情况,提出创新人才培养和改进就业服务的意见

The Application of Aliyun Search Cloud Service to Build Search Engine for Library Sites

利用云搜索服务已成为新的站内搜索技术方向。厦门大学图书馆采用阿里云服务重构站内搜索,将云搜索封装为独立的搜索引擎。网站数据经过预处理后提交、生成索引,传递搜索字符串到云搜索引擎即可使用云服务,实现搜索及结果呈现。评测结果表明,阿里云站内搜索与原有站内搜索相比,在检索效率和功能等多方面有显著提升。The application of cloud search service becomes a new search technical direction.Xiamen University Library chooses Aliyun service to rebuild site search,and packages the cloud search as an independent search engine.After pre-processing,the site data is submitted and index files are generated,then the search strings are passed to the cloud search engine.Base on the cloud search service,searching finished and results displayed.Evaluation results show that Aliyun cloud search,compared with the old search engine,is significantly improved in search efficiency and functionality,etc

用户数据统计挖掘与展示——以厦门大学图书馆“圕·成长”项目为例

大数据时代到来,人们以新的技术和视角看待数据。图书馆如何应用现有数据,挖掘和提炼数据价值,已成为行业关注热点。文章以厦门大学图书馆针对用户数据进行统计挖掘,通过可视化的方法进行展现为例,介绍了厦门大学图书馆"圕·成长"项目的设计思路、实施过程和项目展望

用户数据统计挖掘与展示： 以厦门大学图书馆“圕•成长”项目为例

大数据时代到来，人们以新的技术和视角看待数据。图书馆如何应用现有数据，挖掘和提炼数据价值，已成为行业关注热点。本文以厦门大学图书馆针对用户数据进行统计挖掘，通过可视化的方法进行展现为例，介绍了厦门大学图书馆“圕•成长”项目的设计思路、实施过程和项目展望

Improved recursive constructing method of Reed-Muller codes

一般对rEEd-MullEr码的递归构造方法是对长码进行递归分解,直到不能再分解为止,即出现无冗余码和重复码时结束分解。提出了一种针对rEEd-MullEr码的递归构造改进方法,该改进方法比常规方法在递归分解的两端均提早一步结束对码字的分解,即出现双正交码和单奇偶校验码时结束分解,并对单奇偶校验码采用系统形式。对于双正交码,利用快速哈达玛变换实现快速的最大似然译码;对于单奇偶校验码,利用该码系统形式的特殊构造实现了简化的最大似然译码算法。对改进的译码算法的复杂度进行了详细的分析,并与其他已有的算法进行对比,结果表明,该算法具有更低的复杂度,尤其对于高码率的码型。此外,性能仿真结果表明,该译码算法具有更低的误码率。Reed-Muller code can be recursively decomposed and the decomposition is conventionally ended at repetition codes and non-redundancy codes,where repetition codes and non-redundancy codes cannot be decomposed further.In this paper,we propose a modified recursive structure of Reed-Muller code in which the recursive decompositions are ended one step earlier,i.e.decompositions are ended at dual-orthogonal codes or single parity check codes.Moreover,for single parity check code,the systematic form is used.In the decoding algorithm,we use fast Hadamard transform to simplify the maximum likelihood decoding of dual-orthogonal code.We also use simplified maximum likelihood decoder to decode the systematic single parity check code through its special structure.We analyze the decoding complexity of the proposed decoding algorithm and compare the complexity with two other existing algorithms.The analysis shows that the proposed algorithm has lower complexity,especially for the high-rate codes.In addition,the simulation results indicate that the proposed algorithm decreases the bit-error rate slightly.福建省自然科学基金(2013J01256); 国家自然科学基金(61271241)~

Pressure Measurement of Vacuum Insulation Panel with Infrared Spectroscopy

真空绝热板(VIP)主要是依靠其内部真空度来提高其绝热性能的,由于导热系数是表征真空绝热板绝热性能最重要的物性参数,准确测量出真空绝热板的导热系数,有助于将真空绝热板应用于需要绝热保温的场合并估算出其热负荷情况,为系统选择制冷设备或加热设备提供依据。在对真空绝热板真空度检测技术的研究中,本文致力于研究一种基于热红外技术的真空绝热板真空度检测方法,主要采用埋入热辐射器件、能量由外部无损耦合提供、使用红外热图像处理技术并结合电路控制系统等实现对真空绝热板的真空度检测。实验表明,红外检测技术用于测量真空度是可行的、检测速度快、检测结果可靠;对热红外检测技术的研究有利于推动国内真空度快速检测技术的发展。A novel technique has been successfully developed to non-destructively evaluate the pressure in the vacuum insulation panel( VIP),fabricated on industrial scale.In the newly-developed technique,the heat radiation device,embedded in the VIP and energized in non-contact mode by the lab-built,external power-supply,is capable of emitting infrared( IR) light.The internal pressure can be indirectly estimated via data analysis of the spectrum and image acquired with a digital IR camera.The impact of the time evolution of the pressure on the IR image was experimentally and analytically simulated.The preliminary results show that the newly-developed,IR pressure-probe is feasible to measure rapidly the VIP pressure with high reliability.Further improvement of its measurement accuracy was under way

黔西北土法炼锌区水土流失的特点及防治对策

作者简介: 吴桂容( 1970- ) , 女, 广西贺州人, 博士研究生, 副教授, 主要从事污染生态学研究。E - mail: hzwgr510@ 163. com。通信作者: 敖子强, 博士研究生, 主要从事环境生态和污染生态学研究。E - m ai:l aoz iq iang628@ 163. com。通过对土法炼锌区的土壤、废渣、植物、地表水和沉积物进行实地调查和采样分析,发现土法炼锌区水土流失主要是由于含有SO2和重金属的废气导致植被严重破坏、土壤裸露造成的;水土流失同时导致了重金属的迁移扩散,污染土壤中重金属可溶态比重大,而废渣中重金属可溶态比重小,主要随废渣一起流失。减少土法炼锌区水土流失的主要途径是恢复植被和利用工程措施将废渣固定。对于污染土壤来说限制因子是土壤pH值低,可溶态重金属比重大,主要对策是增加土壤的pH值,选择耐酸性和耐重金属的树种恢复植被;对于废渣来说限制因子是废渣持水保肥能力差,重金属含量高,及废渣本身的结构疏松,主要对策是保持废渣的pH值不降低,利用工程措施将废渣固定,及改变土壤的结构来恢复植被;废渣和污染土壤上的先锋植物醉鱼草(Buddleja lindleyana)可作为首选来恢复植被。贵州省科学技术基金(编号:20062014);广西重点实验室研究基金(编号:桂科能0704K002

Anti-resonance features of destructive quantum interference in single-molecule thiophene junctions achieved by electrochemical gating

基于单个有机分子来构筑电子器件为电子器件微型化提供潜在技术方案。本研究发展了可集成电化学门控的单分子电子器件测试芯片技术和科学仪器方法，在实验和理论两个层面对具有相消量子干涉效应的噻吩衍生物分子器件的电输运过程进行了电化学调控研究，从而首次在室温下实现了对单分子电子器件中量子干涉效应的反共振现象的直接观测和调控，为制备基于量子干涉效应的新型分子材料和器件提供了全新的设计思路和策略。该研究充分展示了电化学调控技术在信息材料和器件领域的重要应用潜力，也体现了我校固体表面物理化学国家重点实验室在电化学研究和科学仪器研发领域的技术积累，以及面向科学前沿开展交叉学科探索的研究特色。 该研究工作是在洪文晶教授、上海电力大学陈文博教授、英国兰卡斯特大学Colin Lambert教授指导下完成的。化学化工学院博士生白杰和李晓慧为论文的共同第一作者，刘俊扬副研究员、师佳副教授、研究生唐永翔、刘帅、黄晓娟、谭志冰和萨本栋微纳研究院的杨杨副教授等也参与了研究工作。田中群教授和毛秉伟教授为该工作提供了重要指导。【Abstract】Controlling the electrical conductance and in particular the occurrence of quantum interference in single-molecule junctions through gating effects, has potential for the realization of high-performance functional molecular devices. In this work, we used an electrochemically-gated, mechanically-controllable break junction technique to tune the electronic behaviour of thiophene-based molecular junctions that show destructive quantum interference (DQI) features. By varying the voltage applied to the electrochemical gate at room temperature, we reached a conductance minimum that provides direct evidence of charge transport controlled by an anti-resonance arising from DQI. Our molecular system enables conductance tuning close to two orders of magnitude within the non-faradaic potential region, which is significantly higher than that achieved with molecules not showing DQI. Our experimental results, interpreted using quantum transport theory, demonstrate that electrochemical gating is a promising strategy for obtaining improved in-situ control over the electrical performance of interference-based molecular devices.This research was supported by the National Key R&D Program of China (2017YFA0204902), National Natural Science Foundation of China (21722305, 21673195, 21503179, 21703188), the Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning, Natural Science Foundation of Shanghai (17ZR1447100), Science and Technology Commission of Shanghai Municipality (14DZ2261000), China Postdoctoral Science Foundation (2017M622060) for funding work in Xiamen. It was also supported by EU Horizon 2020 project QuIET under grant agreement no. 767187EC FP7 ITN ‘MOLESCO’ project no. 606728 and UK EPSRC grants EP/N017188/1 and EP/M014452/1 and Leverhulme Trust (Leverhulme Early Career Fellowships no. ECF-2017-186 and ECF-2018-375) for funding instrumentation used in Lancaster. It was also supported by Hungarian and Czech Academies of Sciences (P2015-107) and Hungarian Research Foundation (OTKA 112034) for funding instrumentation used in Hungary. The authors thank Z.-Q. Tian and B.-W. Mao, Xiamen University, for useful discussions. 该工作获得科技部国家重点研发计划课题（2017YFA0204902），国家自然科学基金委优秀青年科学基金等项目（21722305、21673195、21703188、21503179）以及中国博士后科学基金（2017M622060）等项目的资助，也得到了固体表面物理化学国家重点实验室、能源材料化学协同创新中心的支持