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A Facile Synthesis of Monodisperse Au Nanoparticles and Their Catalysis of CO Oxidation

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Nano Research 2008年第3期1卷 229-234页

作者： Sheng Peng Youngmin Lee Chao Wang hongfeng yin Sheng Dai Shouheng Sun Department of Chemistry Brown UniversityProvidenceRhode Island 02912USA Chemical Sciences Division Oak Ridge National LaboratoryTennessee 37831USA

Monodisperse Au nanoparticles(NPs)have been synthesized at room temperature via a burst nucleation of Au upon injection of the reducing agent t-butylamine-borane complex into a 1,2,3,4-tetrahydronaphthalene solution of HAuCl4·3H2O in the presence of *** as-synthesized Au NPs show size-dependent surface plasmonic properties between 520 and 530 *** adopt an icosahedral shape and are polycrystalline with multiple-twinned *** deposited on a graphitized porous carbon support,the NPs are highly active for CO oxidation,showing 100%CO conversion at-45°C.

关键词： Nanoparticle synthesis Au nanoparticles catalysis CO oxidation

Improving Hydration Resistance of MgO-CaO Clinkers by Depositing MgO Coating

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China's Refractories 2016年第3期25卷 11-16页

作者： yin hongfeng LI Botao GAO Kui DING Songxiong College of Materials and Mineral Resources Xi'an University of Architecture & Technology Faculty of Science and Engineering University of Agder

By carbothermal reduction of Mg O with black carbon as reduction agent at a high temperature,Mg O was deposited on the surface of Mg O- Ca O clinker（ as coating） to improve the clinker ＇s hydration resistance. In the paper,effect of deposition temperature and holding time on the hydration resistance of the treated Mg O-Ca O,the deposition mechanism and Mg O coating kinetics were investigated with hydration resistance test,X-ray diffractometry（ XRD） and scanning electronic microscope（ SEM）. Results showed Mg O coating grew in a2D mode on the surface of Mg O- Ca O particles; the Mg O coating improved the hydration resistance of the coated Mg O- Ca O clinker,and the coated clinker would become stronger when coated at higher deposition temperature and longer holding time. The measurements also found that Mg O deposition process varied with the deposition temperature： it was mainly a chemical-controlled process at temperatures between 1 400- 1 500 ℃,with an apparent activation energy（ AAE） of 97. 8kJ·mol^（-1）; it would change into a diffusion-controlled process when the temperature rising to 1 500- 1 600 ℃,with apparent activation energy of 19. 2kJ·mol^（-1）.

关键词： magnesia- calcia clinker hydration re-sistance magnesia coating carbothermal reduction deposition mechanism

Preparation of Sialon Powder from Coal Gasification Slag

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Journal of Wuhan University of Technology(Materials Science) 2010年第6期25卷 1044-1046页

作者：汤云 State Key Lab of Western Architecture & Technology(Cultivating Base) Xi'an University of Architecture & Technology

X-ray fluorescence spectrometry（XRF）,X-ray powder diffractometry（XRD） and scanning electron microscopy（SEM） were used to characterize the chemical composition,phase constituent and microstructure of the coal gasification *** powders were synthesized by carbothermal reduction and nitridation using the coal gasification slag as raw *** experimental results showed that glass and amorphous carbon were the main phases,quartz and calcite as minor crystalline phases were also presented in porous coal gasification *** constituents of coal gasification slag were SiO2,Al2O3,CaO and residual *** powder with Ca-α-Sialon as main crystalline phase can be synthesized when coal gasification slag powders were reduced and nitrided at 1500 ℃ for 9 h using nitrogen flow of 500 ml/*** coal gasification slag is a valuable and economic starting material for preparing Sialon powders.

关键词： coal gasification slag characterization microstructure Sialon carbothermal reduction and nitridation

TaC/Ti_3SiC_2复合材料的制备与性能

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复合材料学报 2014年第5期31卷 1258-1263页

作者：尹洪峰杨祎诺西安建筑科技大学材料与矿资学院西安710055

采用反应热压烧结法制备了TaC/Ti3SiC2复合材料,借助XRD、SEM、能谱仪以及热重分析等,研究了TaC含量对TaC/Ti3SiC2复合材料的相组成、显微结构、力学性能和抗氧化性的影响。结果表明:采用反应热压烧结法可以制备出致密的TaC/Ti3SiC2复... 详细信息

采用反应热压烧结法制备了TaC/Ti3SiC2复合材料,借助XRD、SEM、能谱仪以及热重分析等,研究了TaC含量对TaC/Ti3SiC2复合材料的相组成、显微结构、力学性能和抗氧化性的影响。结果表明:采用反应热压烧结法可以制备出致密的TaC/Ti3SiC2复合材料,该复合材料的主晶相为Ti3SiC2和TaTiC2,还含有少量的TiC;随着TaC含量的增加,TaC/Ti3SiC2复合材料的弯曲强度和断裂韧性呈现先增大后降低的变化趋势,当TaC含量为30wt%时,二者均达到最大值,此时弯曲强度为404MPa,断裂韧性为4.10MPa·m1/2;TaC的引入,使TaC/Ti3SiC2复合材料抗氧化性能明显优于Ti3SiC2材料。

关键词： TaC Ti3SiC2 复合材料相组成显微结构力学性能抗氧化性

Fabrication and Properties of Ti_3SiC_2/SiC Composites

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China's Refractories 2008年第1期17卷 10-13页

作者： yin hongfeng FAN Qiang REN Yun ZHANG Junzhan School of Material Science and Engineering Xi＇an University of Architecture ＆ Technology Xi＇an 710055 China

Ti3SiC2/SiC composites were fabricated by reactive hot pressing method. Effects of hot pressing temperature, the content and particle size of SiC on phase composition, densification, mechanical properties and behavior of stress-strain of the composites were investigated. The results showed that ：（ 1 ） Hot-pressing temperature influenced the phase composition of Ti3SiC2/SiC composites. The flexural strength and fracture toughness of composites increased with hot pressing temperature. （2） It became more difficult for the composites to densify when the content of SiC in composites increased. It need be sintered at higher temperature to get denser composite. The flexural strength and fracture toughness of composites increased when the content of SiC added in composites increased. However, when the content of SiC reached 50 wt%, the flexural strength and fracture toughness of composites decreased due to high content of pore in composites. （3） When the content of SiC was same, Ti3SiC2/SiC composites were denser while the particle size of SiC added in composites is 12. 8 μm compared with the composites that the particle size of SiC added is 3 μm. The flexural strength and fracture toughness of composites increased with the increase of particle size of SiC added in composites. （4） Ti3SiC2/SiC composites were non-brittle fracture at room temperature.

关键词： Ti3SiC2/SiC composite Mechanical property Phase composition

层状硅酸镍纳米管催化剂的可控制备及其催化性能研究

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无机盐工业 2023年第5期55卷 128-136页

作者：李通尹宏峰中国科学院宁波材料技术与工程研究所浙江宁波315201

通过水热法合成了具有管状结构的层状硅酸镍纳米管材料,并考察了水热反应温度、时间、压力和氢氧化钠用量等对材料形貌和结构的影响。结果表明,氢氧化钠用量、水热反应温度、反应时间是影响层状硅酸镍纳米管形成的关键因素,而水热反应... 详细信息

通过水热法合成了具有管状结构的层状硅酸镍纳米管材料,并考察了水热反应温度、时间、压力和氢氧化钠用量等对材料形貌和结构的影响。结果表明,氢氧化钠用量、水热反应温度、反应时间是影响层状硅酸镍纳米管形成的关键因素,而水热反应压力对层状硅酸镍纳米管材料的形成无明显影响。确定了层状硅酸镍纳米管材料合成的最佳水热反应条件:水热反应温度为200℃、水热反应压力为2 MPa、n(Ni)∶n(NaOH)=1∶(54~72)、水热反应时间为12 h。此外,考察了层状硅酸镍纳米管催化剂在二氧化碳甲烷化反应中的催化性能,结果表明层状硅酸镍纳米管催化剂表现出了优异的二氧化碳甲烷化反应催化性能和反应稳定性,经过72 h的反应测试,催化剂性能没有明显降低,也没有出现镍纳米颗粒团聚烧结现象。

关键词：层状硅酸镍纳米管镍基催化剂可控合成甲烷化烧结

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New Sub-Two Micron BioSEC Particles for High Resolution and High SpeedSeparation of Monoclonal Antibodies in HPLC

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New Sub-Two Micron BioSEC Particles for High Resolution and ...

中国化学会第22届全国色谱学术报告会及仪器展览会

作者： Wu Chen Te-Wei Chu Veronica Qin Gregory Staples hongfeng yin Columns R＆D Agilent TechnologiesInc.

＜正＞Antibody drugs have been spotlighted as therapeutic agents which have a high specificity to the target molecule with few side *** is known that dimer and/or larger aggregates may be produced during the manufacturing process or storage of antibody *** it is possible that these aggregates may become immunogenic to induce antibody production and/or cellular immunity in the body and cause side effects,

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核电厂软岩地基地震反应研究

地震工程与工程振动 2015年第1期35卷 44-49页

作者：尹洪峰薄景山李平中国地震局工程力学研究所黑龙江哈尔滨150080 东北电力设计院吉林长春130021 防灾科技学院河北三河065012

软岩作为核电地基的适宜性问题主要集中在软岩的地震稳定性分析方面,目前我国还没有成熟的计算方法。论文以某核电项目的现场波速试验和室内动力学试验为基础,获得软岩动力学指标,采用一维等效线性化分析方法对核电软岩场地进行了地震... 详细信息

软岩作为核电地基的适宜性问题主要集中在软岩的地震稳定性分析方面,目前我国还没有成熟的计算方法。论文以某核电项目的现场波速试验和室内动力学试验为基础,获得软岩动力学指标,采用一维等效线性化分析方法对核电软岩场地进行了地震反应分析,得到了初步的地震反应结果。在此基础上,综合前人研究所取得的部分成果,对不同剪切波速区段(350 m/s^950 m/s)的软岩,进行了地震反应计算并进行了归纳,进一步验证了软岩对地震波传播的影响规律,并对地震输入界面进行了探讨,提出对重大工程,取剪切波速850 m/s作为地震输入界面。

关键词：核电厂软岩地基动力学特性地震反应

气化炉渣合成Ca-α-Sialon–SiC复相陶瓷

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硅酸盐学报 2011年第2期39卷 233-238页

作者：尹洪峰汤云任耘张军战西安建筑科技大学西部建筑科技国家重点实验室培育基地西安710055

利用X射线荧光分析仪、X射线衍射仪、扫描电子显微镜等研究了Texaco气化炉炉渣的化学组成、物相组成和显微结构。以气化炉渣为原料,分别在1 350,1 400,1 450℃和1 500℃4种氮化温度下碳热还原氮化,利用物相确定和显微结构分析等研究了... 详细信息

利用X射线荧光分析仪、X射线衍射仪、扫描电子显微镜等研究了Texaco气化炉炉渣的化学组成、物相组成和显微结构。以气化炉渣为原料,分别在1 350,1 400,1 450℃和1 500℃4种氮化温度下碳热还原氮化,利用物相确定和显微结构分析等研究了氮化温度对反应的影响。以1 450℃氮化产物为原料,热压制备了Ca-α-sialon–SiC复相陶瓷,并对此材料的力学性能进行了检测。结果表明:(1)Texaco气化炉炉渣主要化学成分为SiO2,Al2O3,CaO和残余碳,其中大多为玻璃相和无定形物质;(2)低温氮化产物主晶相为β-sialon和Ca-α-sialon,高温氮化产物主晶相为Ca-α-sialon和SiC,提高氮化温度更有利于CaO固溶于sialon形成Ca-α-sialon,在1 450℃碳热还原氮化可合成主要成分为Ca-α-sialon和SiC的复相粉体;(3)随着热压温度的升高,Ca-α-sialon-SiC复相陶瓷致密化程度增加,硬度和断裂韧性均有提高,添加剂对材料的力学性能影响较大,添加3%(质量分数,下同)Y2O3+2%MgO,1 650℃热压制备的复相陶瓷的Vickers硬度可达18 GPa,断裂韧性为5.2 MPa?m1/2。

关键词： sialon 碳化硅气化炉渣碳热还原氮化复相陶瓷力学性能