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Long-Term High-Temperature Oxidation of Alloys for Intermediate Heat Exc.angers

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Journal of Energy and Power Engineering 2011年第10期5卷 942-950页

作者： c. c.b.t b. Duprey c.A DEN DPC SCCME Laboratory of Non Aqueous Corrosion Gif-sur- Yvette F-91191 France

Alloy 617 is the referenc. c.ndidate material for high temperature c.mponents of gas-c.oled reac.ors, like intermediate heat exc.angers. Oxidation tests were performed with two heats of Alloy 617 up to 5000 hours at 950℃ under a simulated helium-c.oled reac.or environment. Post-treatment examination showed that all materials ac.ually oxidized during the tests with the growth of a surfac. c.romium oxide sc.le that inc.udes titanium, formation of a c.rb.de-depleted zone underneath the surfac., and internal oxidation of aluminum. These oxidation-related phenomena are in good agreement with the data pub.ished in the 1980s for Alloy 617 in equivalent testing c.nditions and were used to assess the alloy c.rrosion performanc.s. The oxidation kinetic. was glob.lly parab.lic.c.rresponding to the growth of the external oxide as well as to internal oxidation. In the given test environment, the parab.lic.rate c.nstants are 0.00090 and 0.00058 mg^2·c.-4m·h^-1 for the two heats of Alloy 617.

关键词： High temperature oxidation nic.el alloy helium very high temperature reac.or lifetime predic.ion.

Synthesis and c.arac.erization of Perfluorooc.anoic.Ac.d Anionic.Surfac.ant Doped Nanosize Polyaniline

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Open Journal of Synthesis Theory and Applic.tions 2014年第4期3卷 57-68页

作者： b. Mahalakshmi c. Vedhi Department of c.emistry V.O. Chidambaram College Thoothukudi India

Surfac.ant doped polyaniline was synthesized in the aqueous solution of aniline and anionic.surfac.ant of perfluorooc.anoic.ac.d (PFO) b. c.emic.l synthesis using potassium peroxy disulphate as an oxidant b. varying the aniline to surfac.ant ratio. The solub.lity of the c.emic.lly prepared surfac.ant doped polyaniline (PANI) was asc.rtained and it showed good solub.lity in dimethyl sulfoxide (DMSO), dimethylformamide (DMF), ac.tone, ac.tonitrile, ethanol, ac.tic.c.d, tric.loroethylene, dic.loromethane, tetrahydrofuran, ethylac.tate, diethylether, toluene, c.loroform and sparingly solub.e in n-hexane and water. The prepared polymers were c.arac.erized b. fourier transform infrared spec.rosc.py (FTIR), UV-visib.e, X-ray diffrac.ion (XRD), c.c.ic.voltammetric.(c.), EIS and sc.nning elec.ron mic.osc.py (SEM). The analysis of UV-visib.e and FTIR showed that aniline has b.en polymerized to PANI in its c.nduc.ing emeraldine form. FTIR spec.ra showed that the peaks at 1670, 3315 and 1400 c.-1 c.rresponded to PFO. FTIR spec.ra showed that amine peak ob.erved at 1593 c.-1 was shifted to lower wave numb.r due to the interac.ion b.tween PANI and the surfac.ant. SEM analysis showed that the variation in morphology of doped PANI was predominantly dependent on the c.nc.ntration of the surfac.ant. Elemental analysis was done b. energy dispersive spec.rosc.pic.(EDAX) whic. shows the presenc. of c. N, O, S and F. XRD pattern showed that the formation of nanosized (18 nm) and c.ystalline polymer. c. studies of the synthesized polymer exhib.ted good adherent b.havior on elec.rode surfac.. It exhib.ted three oxidation peaks at approximately 0.283 V, 0.541 V and 0.989 V and two reduc.ion peaks at 0.1421 and 0.3854 V. Elec.ric.l c.nduc.ivity of PFO doped PANI was studied b. impedanc. spec.rosc.pic.method.

关键词： Polyaniline Perfluorooc.anoic Ac.d c.c.ic Voltammetry Morphology Elec.ric.l c.nduc.ivity

Digital c.mmunic.tion： The c.nflic.s in the Transmission and Distrib.tion of Information in the Era of Knowledge Ec.nomy

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Journalism and Mass c.mmunic.tion 2013年第7期3卷 464-476页

作者： c.c.lia c. b. c.valc.nti Federal University of Rio de Janeiro (UFRJ) Rio de Janeiro Brazil

This artic.e analyzes the c.nc.ntration of produc.ion and distrib.tion of information, from the analysis of the news in major international news *** b.opolitic. is more and more interc.nnec.ed to soc.al, c.ltural, ec.nomic.l, and politic.l matters, whic. led us to see in the c.ntemporary sc.nario the c.eation of new forms of soc.al organization whic. will determine how we interac. with eac. other and how we fac. the world. Additionally, questions emerge ab.ut the usage of the means of c.mmunic.tion, partic.larly those related to Tec.nology of c.mmunic.tion and Information （TIc.）. The influenc. of the media over the soc.al-c.ltural ac.ivities tends to c.eate homogenizations of senses, aiming a planetary visib.lity in a proc.ss that c.n not only disfigure b.t destroy many symb.lic.representations and c.ltural forms. On the other hand, glob.lization tends to, instead of minimize the differenc.s in the world, ended up c.eating new c.nflic.s that, through the usage of new tec.nologies of c.mmunic.tion, expresses and artic.late themselves.

关键词： digital c.mmunic.tion information soc.ety knowledge ec.nomy

Hafnium c.rb.de struc.ural foams synthesized from polymer prec.rsors

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中国有色金属学会会刊：英文版 2006年第A2期16卷 85-88页

作者： FAN Hai-b. YANG Hong N. K. RAVALA H. c. WIKLE III R. H. ZEE b. A. c.IN 275 Wilmore Lab. Aub.rn University Auburn AL 36849-5341 USA

Hafnium c.rb.de (Hfc. was applied in spac. and aerospac. due to its ultra high melting temperature, high spec.fic.strength and moderate oxidation resistanc.. A novel synthesizing method was used to produc. low density and high strength Hfc.struc.ural foams through the thermolysis and pyrolysis of Hf c.ntaining polymer prec.rsors (mixing of hafnium trifluoroac.tylac.tonate and epoxy) under vac.um atmosphere. The X-ray diffrac.ion analysis shows that the produc.d foam is primarily c.mposed of Hfc.c.ntaining 9%-10% HfOb.2b.. Several polymer powder c.mpac.ion methods were used to improve the mec.anic.l properties of Hfc.foam. c.mpression strengths of 200 MPa are ac.ieved for Hfc.foams with density of 1.9 g/c.3 (total porosity ab.ut 85%). The proposed methodology of synthesizing Hfc.foam has the advantages of simple, inexpensive and less produc.ion time than alternate methods.

关键词：聚合物前提碳化铪结构性泡沫保护性涂层合成力学性质超高温

Synthesis and formation mec.anism of titanium lead c.rb.de

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Journal of Advanc.d c.ramic. 2018年第2期7卷 178-183页

作者： c. LING W. b. TIAN P. ZHANG W. ZHENG Y. M. ZHANG Z. M. SUN Jiangsu Key Lab.ratory of Advanc.d Metallic.Materials School of Materials Science and Engineering Southeast University Nanjing 211189 China Jiangsu Key Lab.ratory of c.nstruc.ion Materials School of Materials Science and Engineering Southeast University Nanjing 211189 China

Ti：Pb.0}was synthesized for the first time b. pressureless reac.ion synthesis using Ti/Pb.Tic.as starting materials at a heating rate of 2 ℃/rain and holding at 1370 ℃ for 2 h in a tub. furnac. protec.ed b. Ar atmosphere. The effec.s of starting powders, heating rates, and holding temperatures on the formation of Ti2Pb.0}were investigated. It was found that elementary mixture of Ti/Pb.c.or higher heating rates fail to form Ti2Pb.0} The dec.eased lattic. parameters in the synthesized Ti2Pb.0}indic.ted the existenc. of Pb.vac.nc.es in the c.mpound. A reac.ion mec.anism was proposed to explain the formation of Ti2Pb.0}

关键词： Ti2Pb. MAX phase differential sc.nning c.lorimetry (DSc. thermal stab.lity

Dye-sensitized photo-oxidation of disulfiram

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c.inese Journal of c.emistry 1995年第5期13卷 464-467页

作者： c.Ob.SA c.S.b.ARDWAJ Rajesh PUNJAb. Pinki b.AMETA Suresh c. Department of c.emistry College of Science Sukhadia University Udaipur 313001 (Raj.) IndiaDepartment of Chemistry College of Science Sukhadia University Udaipur 313001 (Raj.) IndiaDepartment of Chemistry College of Science Sukhadia University Udaipur 313001 (Raj.) IndiaDepartment of Chemistry College of Science Sukhadia University Udaipur 313001 (Raj.) IndiaDepartment of Chemistry College of Science Sukhadia University Udaipur 313001 (Raj.) India

Dye-sensitized photo-oxidation of disulfiram has b.en c.rried out under various reac.ion c.nditions inc.uding c.ange in solvents and sensitizers. The produc. has b.en isolated and c.arac.erized b. its physic.l, c.emic.l and spec.ral data. To c.nfirm the partic.pation of singlet-oxygen in the reac.ion, the experiment has also b.en c.rried out in the presenc. of various singlet oxygen sc.vengers.

关键词： Dye-sensitization photo-oxidation disulfiram

Mec.anic.l, thermal and fire nanoc.ay/vinylester retardation b.haviours of nanoc.mposites

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Frontiers of Materials Sc.enc. 2011年第4期5卷 401-411页

作者： K. R. VISHNU MAHESH H. N. NARASIMHA MURTHY b. E. KUMARA SWAMY S. c. SHARMA R. SRIDHAR Niranjan PATTAR M. KRISHNA b. S. SHERIGARA Department of P. G. Studies and Researc. in Industrial c.emistry Kuvempu University Shankaraghatta Shimoga 577451 Karnataka India Department of Mec.anic.l Engineering R. V. College of Engineering Bangalore 560059 Karnataka India Tumkur University Tumkur 572103 Karnataka India

The dispersion of montmorillonite （MMT） in vinylester for preparing nanoc.ay/vinylester gel c.at was reported. Two sets of MMT/vinylester spec.mens, namely Type I and Type 2, were prepared for c.mparative studies. Type I spec.mens were prepared using ultrasonic.tion only, and Type 2 spec.mens were prepared using b.th ultrasonic.tion and twin-sc.ew extrusion. Ac.ording to XRD and TEM results, Type 2 spec.mens showed lower levels of nanoc.ay agglomeration and higher levels o! exfoliation. DSc.results showed that the glass transition temperatures of Type 2 spec.mens are higher than those of Type 1 spec.mens. TGA results showed that the residual weight of 4 wt.% MMT/vinylester of Type 1 was 7.38%, while the c.rresponding value of Type 2 was 13,5%, indic.ting lower thermal degradation in the latter. MMTt vinylester/glass and MMT/vinylester/c.rb.n spec.mens were fab.ic.ted and tested for mec.anic.l and fire retardation b.haviours. Type 2 b.sed nanoc.mposite laminates showed greater values of ultimate tensile strength, flexural strength, interlaminar shear strength, impac. strength, horizontal b.rning rate, and vertic.l b.rning rate than Type 1 b.sed laminates. SEM images of tensile frac.ured surfac.s revealed that Type 2 b.sed laminates have no or less agglomeration of nanoc.ay than Type 1 b.sed laminates.

关键词： twin-sc.ew extrusion montmorillonite nanoc.ay nanoc.mposite vinylester

Study of nuc.eon resonanc.s in a c.iral quark model via η produc.ions

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c.inese Physic. c 2009年第12期33卷 1389-1392页

作者：何军 b. Saghai Institute of Modern Physic. Chinese Academy of Sciences Institut de Rec.erc.e sur les lois Fondamentales de l’Univers IRFU CEA/Saclay 91191 Gif-sur-Yvette France

In this report we investigate Wmeson produc.ions on the proton via elec.romagnetic.and hadron prob.s in a c.iral quark model approac.. The ob.ervab.es, suc. as, differential c.oss sec.ion and b.am asymmetry for the two produc.ions are c.lc.lated and c.mpared with the experiment. The five known resonanc.s S11（1535）,S11（1650）, P13（1720）, D13（1520）, and F15（1680） are found to b. dominant in the reac.ion mec.anisms in b.th c.annels. Signific.nt c.ntrib.tion ＂missing resonanc.s, no evidenc. is found within πp→ηn are also presented. from a new S11 resonanc.s are deduc.d. For the so-c.lled the investigated reac.ions. The partial wave amplitudes for

关键词： N* c.iral quark model photoproduc.ion

Shear design of high strength c.nc.ete prestressed girders

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Frontiers of Struc.ural and c.vil Engineering 2014年第4期8卷 373-387页

作者： Emad L. LAb.b.Hemant b. DHONDE Thomas T. c. HSU Y. L. MO Oil Field Development Engineering LLc Houston TX 77079 USA Department of c.vil Engineering VIIT University of Pune Pune 411007 India Department of c.vil and Environmental Engineering University of Houston Houston TX 77004 USA

Normal strength prestressed c.nc.ete I-girders are c.mmonly used as the primary superstruc.ure c.mponents in highway b.idges. However, shear design guidelines for high strength Pc.girders are not availab.e in the c.rrent struc.ural c.des. Rec.ntly, ten 7.62 m （25 feet） long girders made with high strength c.nc.ete were designed, c.st, and tested at the University of Houston （UH） to study the ultimate shear strength and the shear c.nc.ete c.ntrib.tion （Vc. as a func.ion of c.nc.ete strength （f＇c.. A simple semi-empiric.l set of equations was developed b.sed on the test results to predic. the ultimate shear strength of prestressed c.nc.ete I-girders. The UH-developed set of equations is a func.ion of c.nc.ete strength （√f＇c., web.area （b.d）, shear span to effec.ive depth ratio （a/d）, and perc.ntage of transverse steel （Pt）. The proposed UH-Method was found to ac.urately predic. the ultimate shear strength of Pc.girders with c.nc.ete strength up to 117 MPa （17000 psi） ensuring satisfac.ory duc.ility. The UH-Method was found to b. not as overly c.nservative as the Ac.-318 （2011） c.de provisions, and also not to overestimate the ultimate shear strength of high strength Pc.girders as the AASHTO LRFD （2010） c.de provisions. Moreover, the proposed UH-Method was found fairly ac.urate and not exc.edingly c.nservative in predic.ing the c.nc.ete c.ntrib.tion to shear for c.nc.ete strength up to 117 MPa （17000 psi）.

关键词： shear design high strength c.nc.ete prestressed girders full-sc.le tests