检索结果-南通市图书馆

Interface Structure and Formation Mechanism of Directly-Bonded Joints of Silicated Graphite to Fe-based Alloys

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2007年第1期23卷 92-96页

作者： Jichun CHEN Chuanyong HAO jinsong zhang Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Commercially available 000Cr3OMo2 ferritic stainless steel and 4J33 ferromagnetic expansion alloy were di- rectly bonded to silicated graphite at 1180-1200℃ and 1100-1150℃, respectively, Intedacial microstructures were examined by scanning electron microscopy, electron probe microanalysis, and X-ray diffraction. The results showed that transient liquid-phase present during bonding promoted the interracial reactions during bonding. Plenty of brittle chromium carbides, such as （Cr, Fe）7C3 and （Cr2.5Fe4.3Mo0.1）C3, were observed in 000Cr3OMo2/silicated graphite joints. Besides, transverse cracks were also found. In case of 4J33/silicated graphite system, well bonded joints free of defects Were obtained.

关键词： Bonding SiC Transient liquid-phase Interracial microstructure

Tobacco floral homeotic gene homologues: partial sequence and expression pattern

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第10期43卷 870-875页

作者： jinsong zhang Shouyi Chen Acad Sinica Inst Genet Beijing 100101 Peoples R China

Using PCR approach, three cDNA sequences, NTSQUA4, NTSQUA12 and NTSQUA15, were amplified from first_strand cDNAs of wild tobacco flower buds and identified as homologues for floral homeotic genes. All the three clones contained domains that a floral homeotic gene generally had, i.e. I domain, K domain and C_terminal domain except MADS_ box since the PCR primers were designed beyond this region. In addition, the amino acid sequences of them showed 50%-60% identity (70%-80% similarity) with the known floral organ identity class A gene AP1 and SQUA, possibly indicating that they are class A_like genes. NTSQUA4 and NTSQUA412 shared 95% identity in their amino acid sequence, while NTSQUA415 exhibited only 47% identity as compared with NTSQUA4 and NTSQUA12. Within tobacco flower, NTSQUA4 was expressed in sepals, petals and carpels, but not in stamens, while NTSQUA15 was expressed in every whorl of the flower. The possible functions of these genes are discussed.

关键词： nicotiana tabacum floral homeotic gene flower organ identity.

Improved monochromatic pyrometry for synchronous measurement of full-field temperature and deformation

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2021年第9期64卷 2033-2046页

作者： zhang jinsong YUE MengKun WANG JinYang TANG YunLong JIANG jinsong GUI YeWei FENG Xue Key Laboratory of Applied Mechanics Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Center for Advanced Mechanics and Materials Tsinghua UniversityBeijing 100084China School of Engineering and Technology China University of GeosciencesBeijing 100083China Chengdu Aircraft Design and Research Institute Chengdu 610041China China Aerodynamics Research and Development Center Mianyang 621000China

Measuring the temperature and deformation synchronously at elevated temperatures is technically challenging and has become a major concern in the evaluation of mechanical properties. In this study, a simple, easy-to-implement, yet effective monochromatic pyrometry is established for non-contact and full-field temperature measurements, which can significantly reduce the error caused by the camera’s channel crosstalk that commonly occurs in the existing improved two-color method. In addition, hightemperature digital image correlation, combined with band-pass filtering and monochromatic illumination, is applied for deformation measurement. Subsequently, an experimental system was set up to validate the accuracy of the proposed method,which consists of a CCD camera for image capturing, a blue bandpass filter for radiation suppression, blue light irradiation for light compensation, and an infrared pyrometer for temperature recording. The results of the thermal heating experiment on the C/SiC sample proved that the selection of camera channel R in monochromatic pyrometry can reduce the error by channel crosstalk,and the proposed method is applicable for synchronous measurement of temperature and deformation.

关键词： synchronous measurement monochromatic pyrometry high-temperature DIC

Hydrochlorination of Acetylene Using SiC Foam Supported Structured C/Au Catalysts

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2014年第5期30卷 434-440页

作者： Xiaodan Yang Chunhai Jiang Zhenming Yang jinsong zhang Institute of Metal Research Chinese Academy of Sciences

AuCl3 loaded structured catalysts were prepared on SiC foam supported with pre-coated activated carbon layers. The catalytic properties of the structured catalysts towards hydrochlorination of acetylene were tested in a fixed- bed reactor with the AuCl3 loaded on activated carbon pellets as a reference. For isopyknic catalysts, the structured catalyst with only one fifth of the Au amount as that was used on the reference catalyst exhibited even a little higher acetylene conversion and much better stability than the latter no matter what the gas hourly space velocities of acetylene were used. The results indicated that the more homogeneous distribution of AuCl3 particles and better heat transfer along the fixed-bed reactor originated from the low pressure drop and high thermal conductivity of the SiC foam supported structured catalysts might be able to account for their improved efficiency and stability. It is befieved that these novel structured C/Au catalysts can be potentially applied in VCM industrialization in view of their greatly reduced cost and much prolonged life.

关键词： Structured catalysts Acetylene hydrochlorination Silicon carbide foams Carbon coating Heterogeneous reaction

A comparative study of Ni/Al_2O_3–SiC foam catalysts and powder catalysts for the liquid-phase hydrogenation of benzaldehyde

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2019年第1期35卷 159-167页

作者： Kai Li Yilai Jiao Zhenming Yang jinsong zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences University of Chinese Academy of Sciences

In this study, Al_2O_3-washcoated SiC(Al_2O_3–SiC) foams and Al_2O_3 powder were employed as the supports of a Ni catalyst for the liquid-phase hydrogenation of benzaldehyde. A series of Ni/Al_2O_3–SiC foam catalysts and Ni/Al_2O_3 powder catalysts with a Ni loading from 10 wt% to 37 wt% of the weight of Al_2O_3 were first prepared by a deposition–precipitation(DP) method. The catalytic activity and recyclability of both kinds of catalysts were then compared. Although it had a smaller accessible surface area with the reactant, the foam catalyst with a Ni loading of 16 wt% exhibited a slightly higher conversion of benzaldehyde after 6 h(of 99.3%) in comparison with the Ni/Al_2O_3 catalyst with identical Ni loading(conversion of 97.5%). When the Ni loading increased from 16 wt% to 37 wt%, the reaction rate obtained with the foam catalyst increased significantly from 0.108 to 0.204 mol L^(-1)h^(-1), whereas the reaction rate obtained with the powder catalyst increased from 0.106 to 0.123 mol L^(-1)h^(-1). Furthermore, the specific activity(moles of benzaldehyde consumed by 1 g min^(-1)of Ni) of the foam catalyst with a Ni loading above 30 wt% was superior to that of the powder catalyst because of its smaller Ni-particle size and higher mass-transfer rate. The foam catalyst displayed a high recyclability as a function of run times owing to the strong interaction between the Ni component and the Al_2O_3 coating. The conversion of benzaldehyde over the foam catalyst remained almost unchanged after being used 8 times. In comparison, a drop of 43% in the conversion of benzaldehyde with the powder catalyst was observed after being used 7 times due to the leaching of the Ni component.

关键词： Foam catalyst Powder catalyst Benzaldehyde hydrogenation Ni loading Recyclability

A Surfactant-stable Bacillus pumilus K9 α-Keratinase and Its Potential Application in Detergent Industry

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2015年第1期31卷 91-97页

作者： GONG jinsong WANG Yue zhang Dandan LI Heng zhang Xiaomei zhang Rongxian LU Zhenming XU Zhenghong SHI jinsong School of Pharmaceutical Science Jiangnan University Wuxi 214122 P. R. China

An a-keratinase producing strain was isolated with wool as the sole carbon and nitrogen source and identified as Bacilluspumilus K9. The major amino acids liberated from the keratin degradation of wool by B. pumilus K9 were glutamic acid and leucine. The a-keratinase was purified to electrophoretic homogeneity with a molecular weight of 32000. The purified enzyme exhibits an optimum activity at 60 ℃ and pH=9.0. It was stable at pH values between 8 and 11. Bacillas pumilus keratinase displays a high activity towards casein, keratin, wool and feather, which indicates its wide application range. The keratinase was completely inhibited by phenylmethyl-sulfonyl fluoride（PMSF） and β-mercaptoethanol, and moderately inhibited by ethylemediamine-tetraacetic acid（EDTA）, suggesting it is a metallo-cysteine keratinase. This enzyme could remain stable that could even be promoted in the presence of surfactants, including sodium dodecyl sulfate（SDS）, Tween and Triton. And Tween 40 and Triton X-100 could substantially enhance the activity of the enzyme by 54% and 35%, respectively. It may indicate the prominent feature of the keratinase to tolerate surfactants. The enzymatic properties distinguish this keratinase from others in the literature. Furthermore, this enzyme is extremely stable in the presence of a commercially available detergent with 1% concentration. Detergents ARIEL, Bluemoon and WhiteCat can enhance the activity of the keratinase by 43.56%, 15.22%, and 22.48%, respectively.

关键词： a-Keratinase Bacilluspumilus K9 Wool degradation Surfactant stability Detergent

Photocatalytic Activities of TiO_2 Coated on Different Semiconductive SiC Foam Supports

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2013年第11期29卷 1074-1078页

作者： Dong Hao Zhenming Yang Chunhai Jiang jinsong zhang Institute of Metal Research Chinese Academy of Sciences University of Chinese Academy of Sciences

Different semiconductive SiC foam supports were prepared by varying the sintering temperature and atmosphere, and with or without alkaline solution treatment and high temperature oxidation following a macromolecule pyrogenation combined with reaction bonding method. Nano-TiO2 particles were immobilized onto these SiC foam supports by a composite sol-gel method. The phase, surface morphology, the type of conduction and the photocatalytic activity of the TiO2-SiC composite photocatalysts were studied. The TiO2 coated on p-type Si-free SiC support showed the highest photocatalytic efficiency in degradation of 4- aminobenzenesulfonic acid （4-ABS） in aqueous solution as compared to that coated on n-type SiC support and p-type SiC supports with residual Si or Si02 on the surface. The result showed that the TiO2 coatings immobilized on p-type semiconductive SiC foam supports exhibited obviously higher photocatalytic activity in comparison to that coated on n-type SiC foam support. The p-n heterojunctions formed between the p-type SiC supports and n-type TiO2 coatings might be able to account for the better charge separation and transfer as well as the photocatalytic activity of the TiO2-SiC composite photocatalyst.

关键词： SiC foam ceramics TiO2 coating Composite Sol-Gel Photocatalytic activity

Microstructure and Strength of Al_2O_3/Al_2O_3 Joints Bonded with ZnO—Al_2O_3—B_2O_3—SiO_2 Glass—Ceramic

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2014年第9期30卷 944-948页

作者： Weiwei Zhu Jichun Chen Chuanyong Hao jinsong zhang Institute of Metal Research Chinese Academy of Sciences

ZnO-Al2O3-B2O3-SiO2 （ZABS） glass powder was used as interlayer to join alumina ceramics. The effect of joining temperature on the microstructure and strength of joints was investigated. The results showed that the ZABS glass can react with alumina substrate to form a layer of ZnAl2O4 at Al2O3/glass interface. Bending test exhibited that low joining temperature （1150℃） led to low joint strength due to the formation of pores in the interlayer, originated by high viscosity of the glass. High joining temperature （1250 ℃） also resulted in low joint strength, because of large CTE （coefficient of thermal expansion） mismatch between amorphous interlayer and alumina substrate. Therefore, only when the joining temperature was appropriate （1200℃）, defect-free interface and high joint strength can be obtained. The optimum joint strength reached 285 MPa, which was the same as the base material strength.

关键词： Alumina Joining Glass--ceramic Microstrueture Strength

Solvent extraction with a three-dimensional reticulated hollow-strut SiC foam microchannel reactor

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2022年第6期35卷 53-62页

作者： Ye zhang Yong Gao Peng Wang Duo Na Zhenming Yang jinsong zhang School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Recently,there has been considerable interest in the use of microchannel reactors for hydrometallurgy of rare earths(REs).Here,a novel integrated microchannel reactor based on the hollow-strut SiC foam material is presented and demonstrated to extract Ce^(3+)and Pr^(3+)using 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester(P507)as the *** typical three-dimensional reticulated structure of the hollow-strut SiC foam was characterized by scanning electron microscopy and X-ray micro computed *** the reactor’s structure plays a key role in fluid mixing and mass diffusion during the extraction process,the structure-performance relationship of the foam was studied by extraction experiments combined with numerical *** the foam with the optimal structure,the influence of the flow rate Q_(0) of the two liquid phases on the extraction efficiency η and overall volume mass transfer coefficient KLa was *** both RE ions,with increasing Q_(0),η decreases while KLa *** the total flow rate of the two phases of 4 ml·min^(-1),the η values of Pr^(3+)and Ce^(3+)reached 98.7%and 97.0%,*** the total flow rate of 36 ml·min^(-1) which was much higher than that of many other microchannel reactors reported in the literatures,the η values of Pr^(3+)and Ce^(3+)still reached 92.2%and 86.9%,respectively,and the KLa values of Pr^(3+)and Ce^(3+)were 0.198 and 0.161 s^(-1),respectively,similar to the high values reported for other microchannel reactors studied in previous *** findings indicate that the hollow-strut SiC foam microchannel reactor is suitable for use in REs extraction.

关键词： Extraction Hollow Foam Microchannels Numerical simulation