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Low-temperature CO oxidation over Au-doped 13X-type zeolite catalysts:preparation and catalytic activity

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Frontiers of Environmental Science & Engineering 2011年第4期5卷 497-504页

作者： Qing YE Donghui LI Jun zhao jiansheng zhao Tianfang KANG Shuiyuan CHENG Department of Environmental Science College of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China

Au-supported 13X-type zeolite(Au/13X)was synthesized using a common deposition-precipitation(DP)method with a solution of sodium carbonate as a precipitate *** testing was conducted to test for catalytic oxidation of CO.A study was conducted on the effects of different preparation conditions(i.e.,chloroauric acid concentration,solution temperature,pH of solution,and calcinations temperature)on Au/13X for CO *** respect to the catalytic activity,the relationship between different the preparation conditions and gold particles in 13X zeolite was analyzed using X-ray diffraction,TEM and *** activity of Au/13X catalysts in CO oxidation was dependent on the chloroauric acid *** XRD results,a higher chloroauric acid concentration induced larger gold nanoparticles,which resulted in lower catalytic *** revealed that higher temperatures induced higher Au loading,homogeneous deposit,and smaller gold clusters on the support of 13X,resulting in higher CO ***,a pH of 5 or 6 generated greater amounts of Au loading and smaller Au particles on 13X than at a pH of 8 or *** may be a result of an effective exchange between Au(OH)_(2)Cl_(2)^(-)and Au(OH)_(3)Cl^(-)on specific surface sites of zeolite under the pH’s 5 and *** sample calcined at 300℃showed the highest activity,which may be due to the sample’s calcined at 200℃inability to decompose completely to metallic gold while the sample calcined at 400℃had larger particles of gold deposited on the *** can be concluded from this study that Au/13X prepared from a gold solution with an initial chloroauric acid solution concentration of 1.5×10^(-3)mol·L^(-1)gold solution pH of 6,solution temperature of around 90℃,and a calcination temperature of 300℃provides optimum catalytic activity for CO oxidation.

关键词： 13X-type zeolite CO oxidation gold solution pH calcination temperature

INHERITANCE OF PRECIPITATED V_4C_3 IN MARTENSITIC TRANSFORMATION

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Acta Metallurgica Sinica(English Letters) 1992年第2期5卷 82-88页

作者： XIE Changsheng SUN Peizhen zhao jiansheng SUN Desheng Huazhong University of Science and Technology,Wuhan,China Huazhong Univ of Science and Technology Wuhan China

The inheritance phenomenon of precipitated V_4C_3 in martensitic transformation has been in- vestigated by means of electron diffraction and matrix analysis.A crystallographic orientation relation among austenite,martensite and V_4C_3 carbide was found to be. (010)_A∥( 10)_M∥(010)_(v_4c_3), [10 ]∥[11 ]_M [10 ]_(v_4c_3) The V_4C_3 first precipitated in austenite,and then was inherited to *** cer- tain orientation relation was kept between V_4C_3 and martensite,the interfacial structural ana- lysis pointed out that the biphase interfacial energy is higher than that determined by Baker-Nutting relation,thus it is *** the V_4C_3 precipitated along the crystalline defects in austenite,they could be inherited to martensite.

关键词： V_4C_3 transformation inheritance orientation

Microstructure and Mechanical Properties of a Duplex Martensite Austenitic Steel Precipitation-hardened by VC Carbide

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Journal of Materials Science & Technology 1994年第5期10卷 367-373页

作者： Changsheng XIE jiansheng zhao Peizhen SUN and Xia LIANG (Dept.of Mech. Eng. Ⅱ, Huazhong University of Science and Technology, Wuhan, 430074, China)(To whom correspondence should be addressed) Huazhong Univ of Science and Technology Wuhan China

This paper presents an investigation on the primary microstructure and mechanical properties of a martensite-austenitic duplex steel precipitation-hardened by VC carbide. The results show that the mechanical properties at room temperature are strongly dependent upon the volume fraction of austenite fA. When fA 32%, with increasing ***. ultimate strength rises and yield strength drops down. Experimental results at elevated temperatures. show that when test temperature ≤500℃. the yield strength to modulus ratio remains unchanged, however. as the temperature rises a substantial fall in the ratio occurs. The strength values at 600 and 700℃ are increased with increasing strain rate measured by cross-head speed of testing rnachine, The law of mixtures and the contribution of strain-induced transformation from unstable austen ite to martensite to the mechanical properties are discussed.

关键词： Martensite

A User Differential Range Error Calculating Algorithm Based on Analytic Method

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Chinese Journal of Aeronautics 2011年第6期24卷 762-767页

作者： SHAO Bo LIU jiansheng zhao Ruibin HUANG Zhigang LI Rui School of Electronics and Information Engineering Beihang University Beijing 100191 China

To enhance the integrity, an analytic method （AM） which has less execution time is proposed to calculate the user differential range error （UDRE） used by the user to detect the potential risk. An ephemeris and clock correction calculation method is introduced first. It shows that the most important thing of computing UDRE is to find the worst user location （WUL） in the service volume. Then, a UDRE algorithm using AM is described to solve this problem. By using the covariance matrix of the error vector, the searching of WUL is converted to an analytic geometry problem. The location of WUL can be obtained directly by mathematical derivation. Experiments are conducted to compare the performance between the proposed AM algorithm and the exhaustive grid search （EGS） method used in the master station. The results show that the correctness of the AM algorithm can be proved by the EGS method and the AM algorithm can reduce the calculation time by more than 90%. The computational complexity of this proposed algorithm is better than that of EGS. Thereby this algorithm is more suitable for computing UDRE at the master station.

关键词： satellite navigation user differential range error integrity analytic method worst user location

Assessment of deep groundwater over-exploitation in the North China Plain

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Geoscience Frontiers 2011年第4期2卷 593-598页

作者： jiansheng Shi zhao Wang zhaoji Zhang Yuhong Fei Yasong Li Feng＇e Zhang Jingsheng Chen Yong Qian Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences Shigang Street 406 ShijiazhuangHebei 050061 China

A series of environmental—geological problems have been caused by over-exploitation of deep groundwater（i.e.,confined aquifer water） in the North China *** order to better understand the status of deep groundwater over-exploitation and the resultant environmental—geological problems on a regional scale,the over-exploitation of groundwater has been assessed by way of the groundwater exploitation potential coefficient（i.e.,the ratio of exploitable amount of deep groundwater to current exploitation）, cumulative land subsidence,and long-term average lowering rate of the groundwater *** is a good correlation among the results calculated by the different *** a regional scale,deep groundwater has been over-exploited and there is no further exploitation potential under the current *** groundwater exploitation degree index takes the exploitation in 2003 as the reference for the calculations, so the results mainly reflect the degree of current groundwater *** results of over-exploitation of deep groundwater obtained by land subsidence data and long-term average rate of depression of the water table mainly reflect environmental—geological problems caused by exploitation of deep groundwater.

关键词： North China Plain Deep groundwater Assessment of over-exploitation Land subsidence Water table depression

非平衡磁控溅射类金刚石薄膜的抗刻划性能及氟对结合强度的影响

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机械工程学报 1999年第5期35卷 80-84页

作者：赵建生许大庆 ChoyKwangLeong 华中理工大学材料科学与工程系武汉430074 ImperialCollegeofScience TechnologyandMedicine

使用非平衡磁控溅射方法沉积了类金刚石（ＤＬＣ）和一定含氟浓度的氟化ＤＬＣ。使用划痕方法试验了不同ＤＬＣ薄膜的抗刻划性能并对其试验机理进行了研究。结果表明划痕试验过程中随着试验载荷的增加，ＤＬＣ破坏形式可分为开裂、崩片... 详细信息

使用非平衡磁控溅射方法沉积了类金刚石（ＤＬＣ）和一定含氟浓度的氟化ＤＬＣ。使用划痕方法试验了不同ＤＬＣ薄膜的抗刻划性能并对其试验机理进行了研究。结果表明划痕试验过程中随着试验载荷的增加，ＤＬＣ破坏形式可分为开裂、崩片、划入剥落及表层的脱落等阶段。其中抗开裂、崩片及划入性能取决于ＤＬＣ本身的力学特性。膜层的脱落载荷取决于膜层与基体的结合强度。降低薄膜的摩擦系数有利于提高ＤＬＣ薄膜的刻划抗力。氟元素的加入可以降低ＤＬＣ层的刻划摩擦力，提高其开裂强度并增加ＤＬＣ薄膜与基体材料的结合强度。

关键词：类金刚石薄膜氟化类金刚石磁控溅射结合强度

EFFECT OF ALLOY ELEMENTS ON QUASIEQUILIBRIUM MICROSTRUCTURE IN Fe-Mn-Ni-Cr STEELS

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Acta Metallurgica Sinica(English Letters) 1990年第1期3卷 52-57页

作者： XIE Changsheng SUN Peizhen zhao jiansheng CHEN Yuqiu Huazhong University of Science and Technology,Wuhan,China XIE Changsheng Associate Professor,Department of Mechanical Engineering No.2,Huazhong University of Science and Technology,Wuhan 430074,China

The microstructures of Fe-Mn-Ni-Cr steels with medium carbon and the effect of alloy ele- ments on them have been investigated by means of X-ray diffraction quantitative phase ana- lyses,metallography and hardness *** volume fraction of martensite in steels quenched at 1100℃ can be expressed as: f_M^(1100)=162.643-15.482Mn-7.36Ni-4.286(Cr+Mo+V) Based on this expression,the quasi-equilibrium microstructure diagram has been *** is shown that the effect of Mn on the austenite stability is greater than that of *** equiva- lent [Ni]=2.104Mn+Ni and equivalent [Cr]=Cr+Mo+V. The driving force for martensite transformation at M_s point has been calculated to he drastically decreased by element Mn.

关键词： quasi-equilibrium microstructure diagram martensitic transformation driving force multi-factor regression analysis

高温固井水泥浆用降失水剂GT-1的制备及性能

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钻井液与完井液 2022年第2期39卷 234-240页

作者：赵建胜代清霍锦华李杨中石化中原石油工程有限公司固井公司河南濮阳457000 四川川庆井下科技有限公司四川德阳618300 西安工程大学环境与化学工程学院西安710048 华北油田公司二连分公司内蒙古锡林浩特026000

随着油气勘探向深井、超深井方向的不断发展,固井作业对其工作液体系及外加剂提出了更高要求。针对目前降失水剂耐温、抗盐性能不足、适应温度范围窄、且与其他外加剂相容性差等问题,基于分子结构设计思想并结合功能单体优选,以2-丙烯... 详细信息

随着油气勘探向深井、超深井方向的不断发展,固井作业对其工作液体系及外加剂提出了更高要求。针对目前降失水剂耐温、抗盐性能不足、适应温度范围窄、且与其他外加剂相容性差等问题,基于分子结构设计思想并结合功能单体优选,以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、丙烯酰胺(AM)、对苯乙烯磺酸钠(SSS)、纳米二氧化硅等为原料制备了高温固井水泥浆用降失水剂GT-1。采用红外光谱、凝胶色谱、热综合及扫描电镜等分析方法研究了其化学结构、分子量、热稳定性及水溶液微观形貌。并对GT-1的失水性能、耐温性能、抗盐性能及所配制水泥浆体系的流变性能、抗压强度和稠化性能进行了研究。结果表明,降失水剂GT-1化学结构符合预期设计,重均相对分子质量为138431,热稳定性优良,且其水溶液呈现规整的空间网状结构;同时,降失水剂GT-1耐温、抗盐性能突出,能够控制水泥浆失水量,且所配制水泥浆工程性能良好,满足固井施工需求,具有较好的应用前景。

关键词：降失水剂耐温性能抗盐性能水泥浆固井固井质量

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山西某矿井煤层瓦斯赋存特征及抽放方案优化

现代矿业 2018年第7期34卷 180-182页

作者：赵建盛山西汾西矿业集团高阳煤矿

分析了山西某矿井煤层瓦斯赋存特征,对矿井22#煤层瓦斯的基础技术参数进行了测定,并对该煤层瓦斯抽放效果进行了评价。认为该矿井瓦斯抽采率仅达到32%,采煤工作面瓦斯抽采率仅为35%,瓦斯抽采浓度也达不到年度计划要求,抽放效果总体不理... 详细信息

分析了山西某矿井煤层瓦斯赋存特征,对矿井22#煤层瓦斯的基础技术参数进行了测定,并对该煤层瓦斯抽放效果进行了评价。认为该矿井瓦斯抽采率仅达到32%,采煤工作面瓦斯抽采率仅为35%,瓦斯抽采浓度也达不到年度计划要求,抽放效果总体不理想。在此基础上,对该矿瓦斯抽放方案进行了优化,在3N2石门22#煤层右三段溜子道施工了顺层瓦斯抽放钻孔,在回风巷道施工了高位钻场布置走向高位钻孔,选用2BEA-353型抽采泵,将抽放负压由-25 k Pa调整为-30 k Pa,钻孔直径由0.072 m调整为0.086 m。研究表明:方案优化后,工作面瓦斯浓度、上隅角瓦斯浓度均有不同程度下降,回风流中的瓦斯浓度也得到明显降低。

关键词：瓦斯抽放瓦斯赋存特征瓦斯参数抽放效果