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Mechanism of forming an ink-bottle-like pore structure based on SBA-15 by a novel MOCVD technique

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Chinese Science Bulletin 2010年第4期55卷 446-451页

作者： ZHANG Ying FRANK Leung-YUK Lam YAN ZiFeng hu xijun School of Chemistry & Chemical Engineering China University of Petroleum Dongying 257061 China Department of Chemical Engineering Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong China

Metallorganic chemical vapor deposition is used as a novel simple pore tailoring method to fine-tune the pore opening size of SBA-15 materials without significant loss in pore volume and surface area. By using acetylene as carbon source and copper (II) acetylacetonate as precursor, the poremouth of SBA-15 is effectively reduced from 5.78 nm to 3.67 nm while maintaining the pore body at 5.78 nm. The effect of four pore modification factors-the ratio of acetylene/nitrogen, the feeding time of carbon precursor, the ratio of SBA-C/Cu(acac)2 and the cycles of MOCVD on the final pore structure of the SBA-15/carbon/copper composite is studied. The morphology and microstructure of the resulting product SBA-C-Cu are characterized by XRD patterns, TEM images and EDS analysis. The XRD and TEM reveal that the SBA-C-Cu composite is highly hexagonally ordered and has similar particle morphology as the original SBA-15.

关键词：金属有机化学气相沉积化学气相沉积技术 SBA 分子筛孔结构铜复合材料化学气相沉积法透射电子显微镜

Fabrication of copper nanorods by low-temperature metal organic chemical vapor deposition

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Chinese Science Bulletin 2006年第21期51卷 2662-2668页

作者： ZHANG Ying Frank Leung-Yuk Lam hu xijun YAN Zifeng State Key Laboratory for Heavy Oil Processing Key Laboratory of Catalysis CNPC University of Petroleum Dongying 257061 China Department of chemical Engineering The Hong Kong University of Science and Technology JiuLong Hong Kong China

Copper nanorods have been synthe-sized in mesoporous SBA-15 by a low-temperature metal organic chemical vapor deposition (MOCVD) employing copper (II) acetylacetonate, Cu(acac)2, and hydrogen as a precursor and reactant gas, re- spectively. The hydrogen plays an important role in chemical reduction of oganometallic precursor which enhances mass transfer in the interior of the SBA-15 porous substrate. Such copper nanostructures are of great potentials in the semiconductor due to their unusual optical, magnetic and electronic properties. In addition, it has been found that chemically modi- fying the substrate surface by carbon deposition is crucial to such synthesis of copper nanostructures in the interior of the SBA-15, which is able to change the surface properties of SBA-15 from hydrophilic to hydrophobic to promote the adsorption of organic cupric precursor. It has also been found that the copper nanoparticles deposited on the external sur- face are almost eliminated and the copper nanorods are more distinct while the product was treated with ammonia. This approach could be achieved under a mild condition: a low temperature (400℃) and vac-uum (2 kPa) which is extremely milder than the con- ventional method. It actually sounds as a foundation which is the first time to synthesize a copper nanorod at a mild condition of a low reaction temperature and pressure.

关键词：化学蒸气沉积法铜有机金属分解低温 MOCVD

Hill-Type Formula and Krein-Type Trace Formula for Hamiltonian Systems

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Analysis in Theory and Applications 2021年第1期37卷 74-101页

作者： xijun hu Yuwei Ou Penghui Wang Hao Zhu School of Mathematics Shandong UniversityJinanShandong 250100China School of Mathematics(Zhuhai) Sun Yat-Sen UniversityZhuhaiGuangdong 519082China Department of Mathematics Nanjing UniversityNanjingJiangsu 210093China

In this paper,we give a survey on the Hill-type formula and its ***,we generalize the Hill-type formula for linear Hamiltonian systems and Sturm-Liouville systems with any self-adjoint boundary conditions,which include the standard Neumann,Dirichlet and periodic boundary *** Hill-type formula connects the infinite determinant of the Hessian of the action functional with the determinant of matrices which depend on the monodromy matrix and boundary ***,based on the Hill-type formula,we derive the Krein-type trace *** applications,we give nontrivial estimations for the eigenvalue problem and the relative Morse index.

关键词： Hill-type formula trace formula conditional Fredholm determinant relative Morse index

Urban River Landscape Design Based on Regional Characteristics——A Case Study of Jinxi River in hushan Town

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Journal of Landscape Research 2014年第1期6卷 13-16,19页

作者： ZHAO Zan hu xijun College of Landscape Architecture Central South University of Forestry and Technology

River is an important resource for human survival and development, and also a material carrier for cultural inheritance. In recent years, with the further urbanization of China, more efforts have been devoted in economic construction, but protection of local ecological pattern and inheritance of historic context have been overlooked. Taking landscape design of Jinxi River in hushan Town for example, local resources were analyzed on the basis of regional characteristics to explore the future development trend. Colorful traditional cultures of south Fujian should be introduced into the design of waterfront landscapes, so historic and cultural elements of south Fujian will be inherited and demonstrated in new means by combining with modern landscape design techniques.

关键词： Regional characteristics Towns River landscape hushan Town Jinxi River

Catalytically active interfaces in titania nanorod-supported copper catalysts for CO oxidation

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Nano Research 2020年第2期13卷 533-542页

作者： Wasim U.Khan Season S.Chen Daniel C.W.Tsang Wey Yang Teoh xijun hu Frank L.Y.Lam Alex C.K.Yip Department of Chemical and Process Engineering The University of Canterbury Christchurch 8041New Zealand Department of Civil and Environmental Engineering.The Hong Kong Polytechnic University Hong Kong.China School of Chemical Engineering The University of New South WalesSydneyNSW 2052Australia Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyHong KongChina

One-dimensional titanium dioxide nanorod(TNR)-supported Cu catalysts(2.5 wt.%-12.5 wt.%)were synthesized using deposition-precipitation.X-ray photoelectron spectroscopy,temperature programmed reduction and CO chemisorption measurements showed that Cu doping over TNR offered metal-support interactions and interfacial active sites that had a profound impact on the catalytic *** role of the Cu-TNR interface was investigated by comparing the catalytic activity of Cu-TNR catalysts with that of pure CuO nanoparticles in CO *** presence of highly dispersed copper species,a high number of interfacial active sites,CO adsorption capacity and surface/lattice oxygen were found to be responsible for the excellent activity of 7.5CU-TNR(ie,Cu loading of 7.5 wt.%on TNR).Moreover,the Cu-TNR catalysts followed the Langmuir-Hinshelwood reaction mechanism with 7.5CU-TNR,exhibiting an apparent activation energy of 44.7 kJ/*** TNR-supported Cu catalyst gave the highest interfacial catalytic activity in medium-temperature CO oxidation(120-240℃)compared to other commonly used supports,including titanium dioxide nanoparticles(TiO2-P25),silica(SiO2)and alumina(Al20g)in which copper species were nonhomogeneously *** study confirms that medium-temperature CO oxidation is highly sensitive to the morphology and structure of the supporting material.

关键词： supported catalysts nanorod oxygen species interfacial active sites CO oxidation

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城市宜居性评价指标体系构建

生态经济 2014年第8期30卷 42-44页

作者：胡伏湘胡希军中南林业科技大学风景园林学院湖南长沙410004

从国内外研究成果入手,通过对宜居城市评价方法的对比分析,提出了城市宜居性评价指标体系的设计原则,设计了覆盖面更全、操作性更强的城市宜居性评价指标体系,包括7个准则层指标、24个领域层指标和81个指标层指标,对科学评价城市宜居性... 详细信息

从国内外研究成果入手,通过对宜居城市评价方法的对比分析,提出了城市宜居性评价指标体系的设计原则,设计了覆盖面更全、操作性更强的城市宜居性评价指标体系,包括7个准则层指标、24个领域层指标和81个指标层指标,对科学评价城市宜居性具有重要的指导意义。

关键词：城市宜居性宜居性评价框架设计指标体系

基于特色景观视野的长沙城市理念识别系统创建

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城市发展研究 2011年第5期18卷 112-117页

作者：胡希军陈玲循中南林业科技大学环境艺术设计学院

长沙作为三千年古城,自文夕大火销毁殆尽后,城市特色建设越来越受到关注。本文在介绍城市理念识别系统相关概念及理念识别系统研究的基础上,分析了长沙城市特色建设的不足,提出长沙心忧天下、敢为人先,山水洲城,娱乐之都的三大理念特征... 详细信息

长沙作为三千年古城,自文夕大火销毁殆尽后,城市特色建设越来越受到关注。本文在介绍城市理念识别系统相关概念及理念识别系统研究的基础上,分析了长沙城市特色建设的不足,提出长沙心忧天下、敢为人先,山水洲城,娱乐之都的三大理念特征,并基于理念识别系统提出三大理念景观的营造措施。

关键词：城市理念识别系统特色景观长沙

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晚清热河避暑山庄河工考述

中国园林 2022年第2期38卷 133-138页

作者：曹盼胡希军中南林业科技大学风景园林学院长沙410004 湖南省自然保护地风景资源大数据工程技术研究中心湖南农业大学东方科技学院长沙410128

避暑山庄与热河河工息息相关。利用档案资料系统地考证了清代热河河工舆图"热河城外河山图"的具体绘制时间与作者,并对于其所绘信息进行了解析。全面识读并分析了刊刻于1888年的热河河工碑碣——"避暑山庄宫墙及武列河堤坝各工程碑""武... 详细信息

避暑山庄与热河河工息息相关。利用档案资料系统地考证了清代热河河工舆图"热河城外河山图"的具体绘制时间与作者,并对于其所绘信息进行了解析。全面识读并分析了刊刻于1888年的热河河工碑碣——"避暑山庄宫墙及武列河堤坝各工程碑""武列河西崖大坝岁修章程碑"。梳理了该河工舆图、碑碣所记载的河工始末,1884—1888年先后2期的河工工程是晚清热河河工之最,并对晚清热河河工工程做了评述。晚清热河河工的考述有助于全面、深刻认识避暑山庄这一经典园林,也于当代涉水实践有启示意义。

关键词：风景园林避暑山庄河工舆图碑碣

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避暑山庄宫墙外引水水系探究

中国园林 2021年第4期37卷 127-132页

作者：曹盼胡希军中南林业科技大学风景园林学院长沙410004 湖南农业大学东方科技学院长沙410128

承德避暑山庄为中国现存最大皇家园林,以自然山水见胜,山庄理水将形式与功能完美融合,具有极高的营建智慧。以往对于避暑山庄理水的研究大都基于以围墙为界,多探讨宫墙内洲渚河湖交错的匠心巧思,而对于宫墙外这一智慧营建的起点鲜有关注... 详细信息

承德避暑山庄为中国现存最大皇家园林,以自然山水见胜,山庄理水将形式与功能完美融合,具有极高的营建智慧。以往对于避暑山庄理水的研究大都基于以围墙为界,多探讨宫墙内洲渚河湖交错的匠心巧思,而对于宫墙外这一智慧营建的起点鲜有关注,为数不多的相关经典研究尚有值得商榷之处。利用清代文档、舆图等文献信息,基于水文学原理,结合实地调研,论证了避暑山庄宫墙外所引之水是来自于武烈河,梳理了舆图"热河城外河山图"的河工信息,重新绘制了避暑山庄早期引水水系示意图,分析了武烈河与狮子沟交汇口河道演变过程。避暑山庄宫墙外引水水系的梳理有助于园林理水系统性的认识。

关键词：风景园林避暑山庄交汇口武烈河引水