Phylogenetic Diversity and Antibacterial Activity of Bacteria Associated with Marine Sponge Mycale sp. from the Coast of Fujian, China

海绵是一类古老的多细胞后生动物，是海洋天然产物最主要的来源之一。目前，越来越多直接或间接的证据表明活性化合物是由海绵内微生物产生或相关的。因此，挖掘海绵共生微生物资源寻找活性化合物已成为世界各国竞相研究的热点。山海绵属（Mycale）主要分布在中国东南沿海，是福建沿海海域药源海绵的优势种群。本研究以Mycalesp.为研究对象，对其可培养共附生微生物进行多样性研究，对分离得到的微生物进行发酵培养，生物活性筛选，次级代谢产物PKS和NRPS功能基因多样性调查，以期为寻找和发现有价值的活性化合物或信息。同时利用微生物分子生态学技术，对海绵成体、幼体以及环境微生物群落进行调查，在揭示不同生长阶段山海...Marine sponge Mycale sp. is the potential source of natural bioactive products. Accumulating evidences indicate that the origin of bioactive compounds in marine sponges may be symbiotic microorganisms, or a cooperative interaction between sponges and associated microorganisms. Mycale sp. is widespread in the coastal region of Fujian sea area, and is a dominant marine sponge species. So, mining the...学位：理学硕士院系专业：海洋与环境学院_海洋生物技术学号：3112010115129

Flowsheet Simulation for Bulk Propylene Polymerization Based on Polymers Plus

对于聚合物生产过程，建立一个既能反映聚合反应机理又能紧密结合装置运行的全流程模型，不仅有助于掌握装置运行的内在规律，而且是装置生产优化和提高经济效益的重要途径。 以国产化的Hypol丙烯本体聚合工艺为研究对象，分析工艺流程的主要组分和操作参数，采用PC-SAFT状态方程作为主要热力学模型；其次根据AspenTech的PolymersPlus软件特点，对工艺流程进行合理的简化和模型化，建立了包括液相聚合反应釜、釜顶蒸汽循环撤热、气相聚合反应器、气相循环撤热、丙烯单体冷凝回收等的流程模型。其中，丙烯聚合反应器是各生产工艺的核心技术，对其建模是流程模拟的难点与关键点。结合Hypol工艺各反应器的生...To develop a flowsheet simulation for industrial polymerization process, which can reflect the polymerization mechanism in essence and combine the unit operation closely, is not only helpful to master the inherence of the polymerization process, but also an important access to improve the plant’s performance and profit. The Hypol technology of polypropylene process was taken as background flowshe...学位：工学硕士院系专业：化学化工学院化学工程与生物工程系_化学工程学号：2062006115202

Method Development on Valence Bond Theory and Its Applications

传统的价键理论方法较少涉及到溶液体系的理论研究及其应用，本文试图发展考虑溶剂效应的价键理论方法并将其进一步扩展到非平衡溶剂化的研究领域。另外，考虑到价键方法的研究领域仍然有限，本论文力图拓展从头算价键方法的应用研究范围。本工作主要包括以下三个方面：1．考虑溶剂效应的从头算价键方法的发展及其程序的编写第三章介绍本课题组最新发展的从头算溶剂化价键方法——VBSM方法。基本理论思路为：通过价键密度矩阵求得原子净电荷，运用Generalized-Born方程求得当前波函数下的极化溶剂化自由能。经过价键自恰场迭代，波函数和能量同时得到优化。VBSM的优点在于它不仅能够计算体系的溶剂化自由能而且能够得到该...In this paper, new Valence Bond (VB) methods for solvent effects are developed. Sequentially ab initio VB methods are applied to several chemical reactions and small molecules. There are three sections in it. 1. Development on VB methods Chapter 3 presents a VB method, called VBSM, to study free energies of solvation by VB methods. The VB calculation takes the polarization free energies which co...学位：理学博士院系专业：化学化工学院化学系_物理化学(含化学物理)学号：B20032503

Ab Initio Computational Method for Classical Valence Bond Theory

价键理论是两大现代化学键理论之一,广泛应用于化学键本质和化学反应机理的研究。由于计算困难,价键理论应用局限于定性的讨论而无法有效地开展从头计算研究。现代经典价键理论在经典价键理论的理论基础上,引入合理有效的计算方法,提高了价键计算的效率。本文回顾近年来经典价键理论从头算方法在提高计算精度和拓展研究范围方面的发展,并简要展望价键理论方法的发展趋势。In modern quantum chemistry,valence bond(VB) theory and molecular orbital(MO) theory are the two general theoretical approaches for chemical bonding.VB theory provides clear interpretation and chemical insights by employing covalent and ionic VB structures explicitly.This review focuses on the methodology development of the current modern classical VB methods in the improvement of computational accuracy and the extension of application areas.Moreover,the further development of modern classical VB methods is briefly prospected.国家自然科学基金项目(No.21120102035;21003101)资

优化资源研发具有影响力的电子结构计算软件包

理论化学的重要性和地位与日俱增,然而作为理论化学的主要研究手段,国内理论化学计算软件发展的现状却不容乐观。本文就当前理论化学国内软件开发工作面临的挑战和机遇,提出若干需要重视的问题

Cause analysis for fine power formation in the process for propylene polymerization in loop reactor

Spheripol环管工艺占我国聚丙烯生产能力的一半以上,该工艺具有转化率高、生产能力大等优点。然而,我国大多数环管装置均不同程度上存在生产过程中经常性出现细粉,影响产品质量以及造成生产不正常的缺陷。结合笔者多年相关的研究,对相关工艺细粉产生的原因进行分析,并提出了一些改进措施。The loop reactors process for propylene polymerization based on the patented Spheripol technology,has over half of the production capacity of polymerization in China,which has many characteristics including high conversion and throughput.Moreover,this technology has some disadvantages such asthe regular fine powder produced in the process for the propylene polymerization.According to authors' several years of works and lots of references,the reasons for the fine power produced in the loop reactors for propylene polymerization are summarized and analyzed in this paper

电学开路挠曲电悬臂梁自振频率分析

挠曲电效应是一种新兴的机电耦合效应,在微纳米尺度的传感器、致动器和俘能器方面有广阔的应用前景.本文基于挠曲电材料的变分原理和电吉布斯自由能,推导了表面覆盖电极的挠曲电悬臂梁在电学开路条件下的机电耦合动力学控制方程和相应的力电边界条件.进一步获得了求解电学开路条件下挠曲电悬臂梁自振频率的超越方程.以聚偏氟乙烯(PVDF)材料为算例,讨论了挠曲电系数、末端质量块和梁尺寸对结构自振频率和电学开路/短路条件下结构自振频率有效频移的影响.计算结果表明,挠曲电系数的增大会提高梁的自振频率;末端质量的增大可以降低梁的自振频率,并且末端质量块的转动效应对悬臂梁自振频率的影响很小;悬臂梁结构的有效频移随着结构尺寸减小而增加,并在某一厚度尺寸趋于饱和值.国家自然科学基金(11572271

MONTE CARLO SIMULATION of SINGLE-/MULTI-ACTIVE SITE CATALYSTS FOR PROPYLENE POLYMERIZATION

采用MOnTE CArlO模拟技术研究了在不考虑聚合物颗粒内物料与热量传递效应及不存在氢气作用下的单、多活性种类催化剂催化的丙烯聚合动力学。探讨了聚合产率、催化剂活性中心分率以及多分散指数随时间的变化规律,并对单、多活性中心种类催化的反应体系分别作了比较。基于MOnTE CArlO方法的模型得出的聚合动力学结果与文献相一致。此外,由MOnTE CArlO模拟也得到,催化剂多活性中心种类的性质对聚合产物的分布性质有很大影响;以多分散指数而言,多活性中心种类催化剂催化得到的聚丙烯多分散指数要比单活性中心种类催化剂催化得到的产物多分散指数宽。A Monte Carlo model was established to describe the propylene polymerization kinetics catalyzed by single-or multi-active site catalyst,ignoring the effects of intraparticle mass and heat transfer and the effect of hydrogen.Corresponding propylene polymerization kinetic data,including polymerization yield,concentration transformation of catalyst active sites,polydispersity etc.,were obtained via the model.Comparisons of the kinetic results between the polymerization catalyzed by the single-active site catalyst and the multi-active site type catalyst were conducted via the model.The simulated kinetic results are found to be in agreement with the reference ones obtained experimentally.The studied results showed that nature of multi-active site type could have a significant influence on polymer distribution properties.As of the polydispersity(PDI),polypropylene catalyzed by multi-active site type catalyst has a broader PDI than the one catalyzed by the single-site catalyst,under the same reaction circumstance.中国石油兰州石油化工研究中心课题(2007019);固体表面物理化学国家重点实验室(厦门大学)课题(200505)项目资

STEADY-STATE MODELING of COMMERCIAL LIQUID PHASE BULK PROPYLENE POLYMERIZATION

采用POlyMErS PluS软件对HyPOl聚丙烯工艺进行了模拟。建立了与现场流程及POlyMErS PluS软件均相匹配的模拟流程;采用PC-SAfT状态方程,并根据zIEglEr-nATTA催化体系的丙烯聚合机理,确定了丙烯聚合动力学。此外,通过文献提供的现场数据分析并确定了丙烯聚合动力学参数。最终建立了完整的HyPOl工艺流程模型。以采集的工业数据对模型进行验证,并采用模型考察了工业稳态操作下的主要工艺条件对丙烯聚合过程的影响。结果表明,模拟结果与工业现场采集数据比较吻合。随着H2进料量增加,聚合产品的熔融指数(MI)增大,数均相对分子质量(Mn)及其多分散分布指数(PdI)下降;催化剂及丙烯进料量的增加都将使各反应釜的聚合物产量增加。The HYPOL technology of polypropylene was simulated by Polymers Plus.First,a flowsheet which incorporates the actual technology into Polymers Plus was obtained.In addition,based on the perturbed-chain statistical associating fluid theory(PC-SAFT) and the propylene polymerization mechanism catalyzed by Ziegler-Natta catalyst,the propylene polymerization kinetics was obtained.Simultaneously,the polymerization kinetic parameters were obtained through the industrial dada provided via literature.Accordingly,the whole process model of the HYPOL technology was developed.The comparison between the simulated and plant data showed that they were in good agreement with each other.The model was also used to investigate the effects of the main operation parameters on the propylene polymerization under steady-state condition.The results indicated that the polymer melt index(MI) increased and the number average relative molecular mass(Mn) of the polymer and its polydispersity index(PDI) both decreased with the increase of the H2 flow rate.The polymer yield increased with the increase of the feed flow rate of catalyst and propylene.中国石油天然气股份有限公司兰州石油化工研究中心资助项