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Advances in chemical Engineering and Science 2017年第2期7卷 108-124页

作者： j.-ch. Buhl Institut für Mineralogie Leibniz Universit&auml t Hannover Hannover Germany

NaBH4 sodalites were obtained by two new modified methods of crystallization: (1) autothermal synthesis and (2) crystallization with crossover from gel to melt flow in NaoH flux. Syntheses results were presented according to XRD, SEM and FTIR. Besides important features of both synthesis procedures product properties like crystal size and morphology were investigated. Spherical agglomerates of microcrystalline sodalite of composition Na7[AlSio4]6BH4(H2o)2 were already observed after 4 h without any external heating by the autothermal procedure. Sodalites of the same average composition but in form of agglomerated nanoparticles are crystallized after very short times (2 h 30’) by the crossover reaction from gel to melt flow. Hydrogen release by heating was further studied for two selected samples with comparable composition from each synthesis procedure. Total hydrogen release by hydrolysis reaction with the internal cage water was found during heating of the autothermal product in synthetic air up to 550°C. In contrast hydrogen release from the nanocrystalline sample of crossover synthesis was not completed when heated under the same conditions. These differences were discussed in terms of crystal size and an earlier loss of the internal water from the nanocrystals of the crossover

关键词： Modified Synthesis Autothermal Process Combined Synthesis Procedures Tailored Tetrahydroborate Sodalites

3D Micromechanical Modeling of Failure and Damage Evolution in Dual Phase Steel Based on a Real 2D Microstructure

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Acta Mechanica Solida Sinica 2016年第1期29卷 95-110页

作者： M.R.Ayatollahi A.ch.Darabi H.R.chamani j.Kadkhodapour Fatigue and Fracture Lab. Center of Excellence in Experimental Solid Mechanics and DynamicsSchool of Mechanical EngineeringIran University of Science and Technology

A plate of dual phase steel was produced from low carbon steel with intercritical annealing treatment. Its optically determined surface microstructure was utilized to construct three different microstructural models. To describe the ductile damage in the ferritic matrix, the Gurson-Tvergaard-Needleman model was used with the failure in the martensite phase being ignored. The numerical results obtained for the mechanism of void initiation and coalescence were compared with the experimental observations. The numerical results obtained from the randomly extruded 3D model showed a significantly better agreement with the experimental ones than those obtained from the 2D model or the uniformly extruded 3D model.

关键词： dual phase steel 3D model microstructure micromechanical modeling GTN dam-age model

Crystallization of Hydrosodalite Na6[AlSio4]6(H2o)8and Tetrahydroborate Sodalite Na8[AlSio4]6(BH4)2inside the openings of Wafer-Thin Steel Mes

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Advances in chemical Engineering and Science 2017年第3期7卷 277-290页

作者： j.-ch.Buhl Institut für Mineralogie Leibniz Universitat HannoverHannoverGermany

The zeolitic properties of hydrosodalite Na6[AlSio4]6(H2o)8 and the reactivity and hydrogen content of tetrahydroborate sodalite Na8[AlSio4]6(BH4)2 favour both species for future industrial applications. A use in chemical process often efforts a sample preparation in form of membrane-like thin wafers. The present study presents experiments on hydrosodalite as well as BH4-sodalite formation as steel mesh supported thin wafers. Preparation of both sodalite wafers is performerd by the crossover synthesis (CS) from solution to melt flow, first described in [1] [2]. Whereas the space filling of the steel mesh with BH4-sodalite crystals was proved to be a complete close and stable package, hydrosodalite reached only a somewhat weaker quality. Beside the synthesis step, hydrosodalite formation requieres a treatment of the crystal filled mesh at 130°C for 20 h in water to transform the as synthesized hydroxysodalite into hydrosodalite, as known from literature [3] [4] [5]. This leaching procedure was found to be responsible for the obtained loss of quality as demonstrated by a further experiment using a self supported hydrosodalite wafer. Further problems like evolution of pores as a result of the mechanically ripping out the steel inlay from the sample pellets after synthesis have to be solved in future. Nevertheless the results of the present paper are of significance for the development of steel mesh supported hydrosodalite and BH4-sodalite membranes.

关键词： Microporous Materials chemical Synthesis Steel Mesh Supported Membranes BH4-Sodalite Hydrosodalite

Corrosion and tribocorrosion behavior of Ti6Al4V/xTiN composites for biomedical applications

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Transactions of Nonferrous Metals Society of china 2022年第2期32卷 540-558页

作者： j.chÁVEZ o.j.MÉNEZ D.BRAVo-BARCENAS L.oLMoS F.ALVARADo-HERNÁNDEZ M.A.GoNZÁLEZ A.BEDoLLA-j.CUINDE M.FLoRES Departamento de Ingeniería Mecánica Eléctrica CUCEIUniversidad de GuadalajaraBlvd.Marcelino García Barragán#1421GuadalajaraC.P.44430México Departamento de Ingeniería de Proyectos CUCEIUniversidad de GuadalajaraJoséGuadalupe Zuno#48Los BelenesZapopanC.P.45150México Departamento de Ingeniería de Proyectos CUCEIUniversidad de Guadalajara-CONACyTBlvd.Marcelino García Barragán#1421GuadalajaraC.P.44430México Instituto de Investigaciones en Ciencias de la Tierra INICITUniversidad Michoacana de San Nicolás de HidalgoAv.Francisco J.Mujica S/NCiudad UniversitariaMoreliaMichoacánC.P.58030México Unidad Académica de Ingeniería I Universidad Autónoma de ZacatecasAv.López Valverde 801ZacatecasZacatecasC.P.98060México Instituto de Investigaciones Metalúrgicas IIMMUniversidad Michoacana de San Nicolás de HidalgoEdificio‘‘U-5’’Ciudad UniversitariaMoreliaMichoacánC.P.58030México

The corrosion and tribocorrosion behavior of Ti6Al4V/xTiN(x=0,5,10 and 15,vol.%)composites fabricated by solid-state sintering and their relationship with the microstructure and microhardness were *** body conditions such as a temperature of 37℃ and a simulated body fluid were *** main results demonstrated a microstructural change caused by theα-Ti stabilization due to solid-solution of nitrogen(N)into the titanium(Ti)lattice,producing a maximum hardening effect up to 109%for the Ti64 matrix by using 15 vol.%*** potentials of composites changed to more noble values with the TiN particle addition,while corrosion current density of samples increased as an effect of the remaining porosity,decreasing the corrosion resistance of ***,changes to a less passive behavior were observed for samples with 15 vol.%*** non-passive behavior of composites resulted in the reduction of the potential drops during rubbing in tribocorrosion ***,an improvement of up to 88%of the wear rate of composites was seen from the solid-solution *** results allowed to understand the relationship between composition and sintering parameters with the improved tribocorrosion performance of materials.

关键词： Ti64 alloy composites powder metallurgy microstructure corrosion tribocorrosion

Contrasting plant growth performance of invasive polyploid and native diploid Prosopis is mediated by the soil bacterial community

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Ecological Processes 2023年第1期12卷 193-203页

作者： Rishabh Kaushik Meesha Sharma ch.V.Ramana ch.Sasikala Maharaj.K.Pandit j.alott’s Hill International Research Centre WarfieldBracknell RG426EYEnglandUK Department of Environmental Studies University of DelhiDelhi 110007India Department of Plant Sciences School of Life SciencesUniversity of HyderabadP.O.Central UniversityHyderabad 500046India Bacterial Discovery Laboratory Centre for EnvironmentInstitute of Science and TechnologyJ.N.T.University HyderabadKukatpallyHyderabad 500085India j.ndal Sch.ol of Environment&Sustainability OP Jindal Global UniversitySonipatHaryana 131001India

Background Soil microbial communities affect above-ground plant diversity and community composition by influencing plant growth *** studies have tested the effect of soil bacterial microbiome on growth performance of native and invasive plants,but the influence of specific bacterial isolates has not been ***,we investigated the effects of soil bacterial exclusion by soil sterilization and by inoculation of Streptomyces rhizobacterial isolates on the growth performance of native and invasive Prosopis *** Plant growth performance of invasive *** was significantly reduced when grown in sterilized soils,whereas native *** showed enhanced growth performance in the sterilized *** grown in the soil inoculated with the specific Streptomyces isolate from ***(Pj.),the growth performance of invasive *** was significantly enhanced while that of native *** seedlings was significantly ***,inoculation of *** and *** seedlings with Streptomyces isolate from the rhizosphere of native ***(PC1)had no significant effect on the growth performances either of *** or *** our study reveals that invasive *** experiences positive feedback from the non-native soil bacterial community,while the native *** experiences negative feedback from its soil bacterial *** results provide fresh experimental evidence for the enemy release hypothesis,and further our understanding of the contrasting growth-promoting effects of differentially recruited microbial species belonging to the same genus(Streptomyces)in the rhizospheres of alien invasive and native plants.

关键词： Soil bacteria Streptomyces Invasive Prosopis j.liflora Prosopis cineraria Soil microbiota

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Synthesis and optical properties of nanosized CdS prepared in a quaternary CTAB/n-hexanol/n-heptane/water reverse micelle

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chinese Science Bulletin 2001年第22期46卷 1873-1877页

作者： Zhang, j.Sun, LD Qian, C Liao, CS Yan, ch Peking Univ PKU HKU Joint Lab Rare Earth Mat & Bioinorgan Chem State Key Lab Rare Earth Mat Chem & Applicat Beijing 100871 Peoples R China

Quaternary water-in-oil reverse micelles consisting of cetyltrimethylammonium bromide (CTAB), n-hexanol, n-heptane and water were prepared and characterized. The optimized reaction conditions were determined, and monodispersed droplets of the reverse micelles were used as microreactors to synthesize CdS nanoparticles. By using transmission electron microscopy (TEM), UV-Vis spectroscopy and fluorescence spectroscopy, the influences of the reverse micelle components on the size, size distribution, morphology, stability and optical properties of CdS nanoparticles were investigated. CdS nanoparticles with narrow size distribution were obtained and the size range is 6-8 nm when W=24 (W=[water]/[CTAB]), F=5.27 (P=[n-hexanol]/ [CTAB]), [CTAB]=0.2 mol/L, [Cd2+] and [S2-] are 8.45×10-4 mol/L.

关键词： reverse micelles CdS nanoparticles optical properties.

FoRMABILITY CRITERIA oF INTERMETALLIC CoMPoUNDS CoNTAINING TRANSITIoN METAL SYSTEMS

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中国有色金属学会会刊：英文版 1997年第3期7卷 136-139页

作者： Guo, j.Li, ch Qin, P chen, NY Cao, Y Qiu, GF chINESE ACAD SCI SHANGHAI INST METSHANGHAI 200050PEOPLES R CHINA SUZHoU UNIV DEPT CHEMSUZHOU 215006PEOPLES R CHINA

ＦＯＲＭＡＢＩＬＩＴＹＣＲＩＴＥＲＩＡＯＦＩＮＴＥＲＭＥＴＡＬＬＩＣＣＯＭＰＯＵＮＤＳＣＯＮＴＡＩＮＩＮＧＴＲＡＮＳＩＴＩＯＮＭＥＴＡＬＳＹＳＴＥＭＳＧｕｏＪｉｎ，ＬｉＣｈｏｎｇｈｅ，ＱｉｎＰｅｉ，ＣｈｅｎＮｉａｎｙ... 详细信息

ＦＯＲＭＡＢＩＬＩＴＹＣＲＩＴＥＲＩＡＯＦＩＮＴＥＲＭＥＴＡＬＬＩＣＣＯＭＰＯＵＮＤＳＣＯＮＴＡＩＮＩＮＧＴＲＡＮＳＩＴＩＯＮＭＥＴＡＬＳＹＳＴＥＭＳＧｕｏＪｉｎ，ＬｉＣｈｏｎｇｈｅ，ＱｉｎＰｅｉ，ＣｈｅｎＮｉａｎｙｉＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔ...

关键词： formability criterion intermetallic compound transition element

LANGMUIR－BLoDGETT　FILM　oF　STRoNG　LUMINESCENT　EURoPIUM　DIBENZoYLMETHANE　CoMPLEXES

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chinese chemical Letters 1995年第10期6卷 903-906页

作者： Zhou, Dj.Yao, GQ Huang, ch Bai, j.Li, TK Beij.ng Univ State Key Lab Rare Earth Mat Chem & Applicat Beijing 100871 Peoples R China Acad Sinica Inst Photog Chem Beijing 100101 Peoples R China

Two strong fluorescent amphiphilic europium-dibenzoylmethane complexs Me3NC 16,H33.F(DBM)(A) and ***(DUM)4 (B) have heed synthesized and1 their Langmuir films have been formed at theair/water *** Langmuir film of of A can be easily transferred onto hydrophific substrates with transferratio around unity to huild up Langmuir-Blodgett(LB)*** LB films were characterized by UV-vis speetraand low-angle X-ray diffraction. Their fluorescence spectra and fluorescence lifetime have heen studied both insolution and highly ordered LB films.

关键词：

Endoscopic and Endosonographic Diagnostic

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The chinese-German j.urnal of Clinical oncology 2004年第4期3卷 213-214页

作者： A. H. Hlscher H. Schfer ch. Gutschow j. Leers Department for Visceral- and Vascular Surgery University of CologneDepartment for Visceral- and Vascular Surgery University of CologneDepartment for Visceral- and Vascular Surgery University of CologneDepartment for Visceral- and Vascular Surgery University of Cologne Cologne GermanyCologne GermanyCologne GermanyCologne Germany

Endoscopy together with endoscopic ultrasonography (EUS) are the most important diagnos- tics for esophageal cancer and staging of the primary. The results have important clinical consequences concerning type of resection or multimodal approach. Further re?nements of endoscopy will increase its signi?cance especially for early cancer. EUS has an accuracy of 80% for the primary compared to 60% for the N-staging. Therefore EUS represents the gold standard for T-staging but it is of little value for detection of lymph node metastasis.

关键词： esophageal cancer endoscopy ch.omoendoscopy endoscopic ultrasonography

Slope Instability on Pyroclastic Deposits: Landslide Distribution and Risk Mapping in Zacapoaxtla, Sierra Norte De Puebla, Mexico

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j.urnal of Mountain Science 2006年第1期3卷 1-19页

作者： Borj.-Baeza R.C. Esteban-chávez o Marcos-López j. Pea-Garnica R.j. Alcántara-Ayala I. Institute of Geography UNAM Circuito Exterior C.U. Coyoacan 04510 Mexico D.F. Institute of Geography UNAM Circuito Exterior C.U. Coyoacan 04510 Mexico D.F.Institute of Geography UNAM Circuito Exterior C.U. Coyoacan 04510 Mexico D.F.Institute of Geography UNAM Circuito Exterior C.U. Coyoacan 04510 Mexico D.F.Institute of Geography UNAM Circuito Exterior C.U. Coyoacan 04510 Mexico D.F.

In october 1999, rainfall induced landslides devastated different communities of the Sierra Norte, Puebla, causing more than 250 victims and economic losses greater than $ 450 million. The town of Zacapoaxtla was one of the sectors most affected by slope instability due to the existing geological features and geomorphic characters determined by material properties, landforms and processes. Extensive areas formed by pyroclastic piedmonts developed on the Quaternary volcanic ignimbrite deposits highly dissected by marginal gully erosion combined with an extreme rainfall event played a significant role as an ideal scenario for the occurrence of landsliding. Distribution of landslides triggered by rainfall within the main sector of the Zacapoaxtla municipality was analyzed by using IKoNoS images in terms of exploring the likely relationship between mass movement incidence and levels of vegetation density. The later was undertaken by means of producing an NDVI and applying a fragmentation algorithm. Finally, a map of potential areas of mass movements risk was produced based on the combination of a socio-economic vulnerability index, geologic and geomorphological maps and the spatial landslide distribution.

关键词： Rainfall landslides IKoNoS vegetation density risk Mexico