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Size and support effects for CO oxidation on supported Pd catalysts

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Science China Chemistry 2010年第9期53卷 2047-2056页

作者： WANG ZhaoWen,LI Bin,CHEN MingShu,WENG WeiZheng & WAN HuiLin State Key Laboratory of Physical Chemistry of Solid Surfaces national engineering Laboratory for {2. chemical productions of alcohols-ethers-esters Department of Chemistry,College of Chemistry and chemical engineering,Xiamen University,Xiamen 361005,China 1. State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen University Xiamen 361005 China2. National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters Xiamen University Xiamen 361005 China3. Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

Supporting Pd catalysts characterized significant different size distribution were obtained using PdCl2.[Pd(NH3)4](NO3)2.and Pd(acac)2.as ***-resolution transmission electron microscopy(TEM),X-ray diffraction(XRD),in-situ Fourier transform infrared spectroscopy(FTIR) and Raman spectroscopy were used to examine the dispersion of *** performance measurements show that the activities for CO oxidation increase as the Pd particle size decreases and the O2.CO ratio *** activities under oxygen rich conditions are significantly higher than those at near the stoichiometric *** on TiO2.prepared by the Pd(acac)2.precursor is highly dispersed,leading to a considerable activity for CO oxidation at near room *** oxidation on the 1 wt% Pd/TiO2.and under an O2.CO ratio of 1 characterized an apparent activation energy of 36.7 kJ/mol,which is closed to those reported for CO oxidation on the supported Au *** present work demonstrates a high catalytic activity of highly dispersed noble metals,and suggests a promising approach of using noble metals as catalysts with exceeding high efficiency.

关键词： noble metals supported palladium CO oxidation size effect support effect

Hydroalumination of diazo and azido compounds:An Al-H addition to end-on nitrogen of substrates

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Science China Chemistry 2010年第9期53卷 1970-1977页

作者： CHU ChenHui1,YANG Ying1,2.& ZHU HongPing1 1State Key Laboratory of Physical Chemistry of Solid Surfaces national engineering Laboratory for {2. chemical productions of alcohols-ethers-esters College of Chemistry and chemical engineering,Xiamen University,Xiamen 361005,China 2.chool of Chemistry and chemical engineering,Central South University,Changsha 410083,China 1. State Key Laboratory of Physical Chemistry of Solid Surfaces national engineering Laboratory for {2. chemical productions of alcohols-ethers-esters College of Chemistry and chemical engineering Xiamen University Xiamen 361005 China2. School of Chemistry and Chemical Engineering Central South University Changsha 410083 China

This paper reports the reactions of a monomeric aluminum dihydride LAlH2.L = HC[C(Me)N(Ar)]2.Ar = 2.6-i-Pr2.6H3) with diazo,azido,and terminal alkyne *** reaction of LAlH2.with N2.H(SiMe3) and N3(1-Ad) occurred through an Al-H addition to end-on nitrogen to yield respective compounds LAl[N(H)N = CH(SiMe3)]2.1) and LAl[N(H)N=N(1-Ad)]2.2.,while the reaction of LAlH2.with PhC≡CH occurred through a stepwise deprotonation to yield LAlH(C≡CPh)(5) and LAl-(C≡CPh)2.6),respectively.2.further reacted by N2.release to yield LAl[NH(1-Ad)][N(H)N=N(1-Ad)](3) and LAl[NH-(1-Ad)]2.4) upon the increased temperature *** 1-6 have been fully characterized,revealing novel reactivity patterns of LAlH2.toward different substrates under the steric influence from the bulky L ligand at Al.

关键词： hydroalumination bulky aluminum hydride multiple-bond molecule Al–H addition

Size control of silver nanoparticles via continuous-flow biosynthesis process

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Size control of silver nanoparticles via continuous-flow bio...

颗粒学最新进展研讨会——暨第十届全国颗粒制备与处理研讨会

作者： Hongyu Liu~(a,b,c,d) Jiale Huang~(b,c,d) Qingbia Li~(a,b,c,d) Lijing Wu~(b,c,d) a(Environmental Science Research Center,College of Oceanography and Environmental Science,Xiamen University,Xiamen 361005,PR China) b(Department of chemical and Biochemical {2.,College of Chemistry and chemical {2.,Xiamen University,Xiamen 361005,PR China) c(national {2. Laboratory for green chemical productions of alcohols,ethers and {12.,Xiamen University,Xiamen 361005,PR China) d(Key Lab for chemical Biology of Fujian Province,Xiamen University,Xiamen 361005,PR China)

Size control biosynthesis of silver nanoparticles(AgNPs) by continuous-flow process in microreactors with different types was demonstrated in this *** Platycladi(***) extract is served as both reducing and capping *** effect of volumetric flow rate,concentration of *** extract,interface of different materials and different diameter of *** the completion of nucleation and the particle growth dynamics(size) were *** of AgNPs were examined by UV-Visible Spectroscopy,transmission electron microscopy(TEM),X-ray diffraction(XRD),and energy dispersive X-ray(EDX) *** was found that two distinguished particle size distribution are formation(several nm and dozens of nm) in the process of continuous flow synthesis when the biomass was abundant.

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Synthesis of β-Amino-α-ferrocenyl alcohols

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Synthesis of β-Amino-α-ferrocenyl Alcohols

中国化学会第四届有机化学学术会议

作者： ZHAO, Hai-Ying BIAN, Zhan-Xi LI, Bao-Guo (College of Chemistry and chemical engineering, Inner Mongolia University, Huhhot 01002.)

＜正＞β-Aminoalcohols are useful intermediates in organic chemistry. The classical methods for the preparation ofβ-aminoalcohols have been developed including reduction of ketone cyanohydrins orβ-nitromethyl alcohols. Both procedures have suffered from lack of generality and low overall yields as does the reaction of ammonia with epoxides. However, the reduction of the protected cyanohydrins can be carried out efficiently, and a wide variety of aliphatic and aromaticβ-aminoalcohols have been gained. Nevertheless, there are no reports on the preparation ofβ-amino-α-ferrocenyl alcohols until now. Herein, we report the synthesis ofβ-aminoalcohols containing ferrocene by the reduction of cyanohydrin trimethylsilyl ethers of acylferrocenes with lithium aluminum hydride.

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Highly Efficient Kinetic Resolution of Allylic alcohols through Redox Isomerization Process Catalyzed by Chiral BINAP-Rhodium Complex

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Highly Efficient Kinetic Resolution of Allylic Alcohols thro...

中国化学会第十届全国有机合成化学学术研讨会

作者： Xiaomin Xie,Kai Ken,Zhaoguo Zhang School of Chemistry and chemical engineering,Shanghai JiaoTong University,800 Dongchuan Road, Shanghai 2.02.0,P.R.China

＜正＞The transition-metal-catalyzed redox-isomerization of allylic alcohols represents a useful synthetic method to generate saturated carbonyl compounds（aldehydes or ketones）.Recently,the asymmetric redox-isomerization of allylic alcohols has attracted great ***,there are only a few reports on the kinetic resolution of allylic alcohols by the redox-isomerzation,and the activity of the reported catalytic systems was *** researched the kinetic resolution of secondary allylic alcohols by

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Catalytic conversion of biomass to fuels and chemicals

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Catalytic conversion of biomass to fuels and chemicals

第五届中美化学工程学术会议

作者： YongWang Pacific Northwest national Laboratory USA

＜正＞Depleting oil reserves and increasing environmental concerns have made biomass derived fuels and chemicals an attractive *** the long term,however,bio-based refineries must have diverse product base to remain economically viable in the absence of government *** can be broken down into four major categories - forest resources,agricultural resources,municipal solid waste,and animal waste.A range of processes are available for conversion of biomass into liquid fuels and *** processes can be grouped into the following classes:gasification of lignocellulosic biomass for syngas production followed by syngas conversion, conversion of lignocellulosic biomass for bio-oil production and upgrading,production of sugar monomers and their conversion by fermentation and thermo chemical approaches,and triglyceride *** derived feedstocks are highly oxygenated compounds that have a high degree of functionality and low thermal *** phase processing not only is compatible with processing of wet biomass feedstocks but also allows the conversion of less stable biomass feedstocks without thermal *** of biomass in aqueous phase typically involves reactions that require hydrogen such as selective hydrogenation and C-C/C-O *** processing and the nature of biomass feedstocks also present additional catalyst and reaction {2. *** talk will present our recent advances in fundamental understanding of the roles of catalyst promoters,supports and pretreatment on the catalyst activity,selectivity and stability,con- trolling of reaction pathways by homogenous and heterogeneous catalysis,and reaction {2. innovations in small scale biomass *** following topic areas will be discussed:depolymerization of lignocellulosic biomass,selective hydrogenation of fermentation-derived acids and salts to useful chemicals,conversion of sugar/sugar alcohols to polyols, is

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不同流加发酵方式对重组枯草芽孢杆菌生产维生素B_2.影响(英文)

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天津大学学报 2006年第B6期39卷 7-12页

作者：陈涛武秋立李晓静陈洵赵学明天津大学化工学院天津300072

在5 L发酵罐中培养重组枯草芽孢杆菌RH33生产核黄素,该重组菌的染色体上含有多个解除了转录调节的核黄素操纵子．由于过高的初糖浓度导致严重的代谢溢流,因此间歇发酵过程只能得到较低的菌体量和产物产量．分别采用了3种不同的流加培养... 详细信息

在5 L发酵罐中培养重组枯草芽孢杆菌RH33生产核黄素,该重组菌的染色体上含有多个解除了转录调节的核黄素操纵子．由于过高的初糖浓度导致严重的代谢溢流,因此间歇发酵过程只能得到较低的菌体量和产物产量．分别采用了3种不同的流加培养方式：分批流加、恒速流加和葡萄糖限制流加来减弱代谢溢流并提高核黄素的产量．同间歇培养相比,分批流加培养能微弱提高重组菌的核黄素产量,而恒速流加和葡萄糖限制流加均能显著提高菌体量和核黄素产量．对于恒速流加培养,当流加速率为0．48 mL／min时核黄素产量和菌体量可以分别达到9．8g/L和2.．3g/L对于葡萄糖限制流加培养,通过人工控制葡萄糖流加速率使培养基中的葡萄糖浓度为10～2.g/L时,重组菌RH33可以达到最高的核黄素产量和菌体量(分别为12.5g/L和34．7g/L)．在葡萄糖限制流加培养中核黄素产率约为0．06 g(核黄素)／g(葡萄糖),高于其他几种培养方式．

关键词：枯草芽孢杆菌核黄素间歇培养流加培养

不同热风干燥温度对番木瓜粉品质与香气成分的影响

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热带作物学报 2018年第2期39卷 372-379页

作者：杨晓红赵宏亮丁陈潘永贵陈文学施瑞成魏静张伟敏海南大学材料与化工学院海南海口570228 海南省产品质量监督检验所海南海口570203 海南大学食品学院海南海口570228 海南省食品检验检测中心海南海口570314

采用国标方法分别对番木瓜粉在不同温度(60、80、90和100℃)下主要营养成分(蛋白质及氨基酸、粗脂肪、水分、碳水化合物)组成和含量及其物化特性的变化进行了测定,并利用顶空固相微萃取结合气质联用技术对不同温度下热风干燥所得番木瓜... 详细信息

采用国标方法分别对番木瓜粉在不同温度(60、80、90和100℃)下主要营养成分(蛋白质及氨基酸、粗脂肪、水分、碳水化合物)组成和含量及其物化特性的变化进行了测定,并利用顶空固相微萃取结合气质联用技术对不同温度下热风干燥所得番木瓜粉香气成分进行了分析。结果表明:番木瓜粉的色泽、褐变度随着温度的升高而加深;番木瓜粉的水分与蛋白质含量随干燥温度升高而逐渐降低,粗脂肪和碳水化合物的含量则随干燥温度升高而逐渐增加,灰分含量则受干燥温度的影响变化不明显;番木瓜粉氨基酸含量随干燥温度的升高而降低,以天门冬氨酸和精氨酸变化最为显著。番木瓜粉中的酸类、醇类、酯类和烃类化合物随着干燥温度的升高而逐步减少,而具有不良气味的醛类和酮类化合物则随干燥温度的升高而逐步增多。综上所述,以60℃干燥温度为最宜。

关键词：番木瓜热风干燥营养成分香气成分

1-MCP处理对不同成熟度富士苹果贮后货架品质和挥发性物质的影响

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食品工业科技 2018年第21期39卷 263-269页

作者：张鹏陈帅帅李江阔李博强国家农产品保鲜工程技术研究中心(天津)天津市农产品采后生理与贮藏保鲜重点实验室天津300384 大连工业大学食品学院辽宁大连116034 中国科学院植物研究所资源植物重点实验室北京100093

为了明确1-甲基环丙烯(1-MCP)对不同成熟度的苹果品质和挥发性物质的影响规律,以不同成熟度的富士苹果为试材,采后进行1μL/L的1-MCP处理,然后在(-0.5±0.3)℃贮藏10个月后出库,测定理化指标,并分析不同成熟度1-MCP处理苹果在货架期间... 详细信息

为了明确1-甲基环丙烯(1-MCP)对不同成熟度的苹果品质和挥发性物质的影响规律,以不同成熟度的富士苹果为试材,采后进行1μL/L的1-MCP处理,然后在(-0.5±0.3)℃贮藏10个月后出库,测定理化指标,并分析不同成熟度1-MCP处理苹果在货架期间果实挥发性物质种类和含量的变化。结果表明,1-MCP处理能够延缓不同成熟度苹果中可溶性固形物、可滴定酸含量和质地的下降,其中1-MCP处理对低成熟度果实保鲜效果更明显。HS-SPME/GC-MS分析表明,己醛(青草及苹果香味)和2.己烯醛(新鲜水果型清香)是富士苹果的主要挥发性物质。在货架初期,高成熟度的果实检测出酯类物质的种类和含量高于低成熟度果实; 1-MCP处理的果实中酯类挥发性物质含量降低,使果实的香气变淡,而醇类、醛类物质含量升高;随着果实的成熟,生理代谢旺盛,1-MCP处理成熟低的果实挥发物质含量升高。

关键词：成熟度富士苹果 1-甲基环丙烯挥发性物质