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h2/CO/air premixed and partially premixed flame structure at different pressures based on reaction limit analysis

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Science Bulletin 2018年第19期63卷 1260-1266页

作者： Zaigang Liu Wenjun kong jean-Louis Consalvi Wenhu han Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China School of Engineering Sciences. University of Chinese Academy of Sciences Beijing 100049 China IUSTI UMR 7343 Aix-Marseille Universite CNRS Marseille 13453 France

Premixed and partially premixed flames (PPFs) of h2/CO/air syngas are studied numerically to investigate the effect of pressure on syngas PPF structure. Chemical characteristics of the syngas flame at different pressures are investigated based on reaction limit analysis using a one-dimensional configuration. The results show that CO affects the syngas reaction limits through both physical effects that consist mainly in dilution and chemical effects that are related to both R23 (CO+Oh=CO2+h) and hCO pathway. In particular, the hCO pathway weakens the flame at low pressures due to the chain-terminating effect of R25 (hCO+O2=CO+hO2) and R26 (hCO+h=CO+h2), and enhances the flame at high pressures because of the contribution of R25 to the hO2chain-branching process. These CO chemical characteristics are also observed in the premixed zone of 50%h2+50%CO syngas PPFs whereas only R23 is important in the non-premixed zone.

关键词： Syngas Partially premixed flame Pressure effect Reaction limit Flame structure

Preparation and characterization of h_4SiW_(12)O_(40)@MIL-100(Fe) and its catalytic performance for synthesis of 4,4'-MDA

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Chinese journal of Chemical Engineering 2018年第2期26卷 330-336页

作者： Yunhuan kong Xiaomeng Cheng hualiang An Xinqiang Zhao Yanji Wang hebei Provincial Key Lab of Green Chemical Technology and Efficient Energy Saving School of Chemical Engineering and TechnologyHebei University of Technology

The catalytic performance of co mmonly used heteropolyacids （h3PW12O40, h4SiW12O40 and h3PMO12O40 synthesis of 4,4＇-methylenedianiline （4,4＇-MDA） from aniline and formaldehyde was evaluated and the result showed that h4SiW12O40 with moderate acid strength exhibited the best catalytic performance. Then haSiW12O40@MIL-100（Fe） was prepared by encapsulating h4SiW12O40 within the pores of MIL-100（Fe） to facilitate its recovery and reuse. The prepared h4SiW12O40@MIL-100（Fe） was characterized by means of FT-IR, N2 adsorption-desorption, XRD, TG and then the catalytic performance was evaluated. The result showed that h4SiW12O40 was highly dispersed in the pores of MIL-100（Fe）, and both the Keggin structure of haSiW12O40 and the crystal skeleton structure of MIL-100（Fe） could be effectively/preserved. Furthermore, h4SiW12O40@ MIL-100（Fe） showed excellent catalytic performance under the following reaction conditions： a molar ratio of aniline to formaldehyde = 5, a mass ratio of catalyst to formaldehyde = 1.2, a reaction temperature of 120 ℃ and a reaction time of 6 h. Under the above reaction conditions, the conversion of aniline was 41.1%, and the yield and selectivity of 4,4＇-MDA were 81,6% and 79.2%, respectively. Unfortunately, an appreciable loss in the catalytic activity of the recovered h4SiW12O40@MIL-100（Fe） was observed because of the blocking of the pores and the change of the acidity resulted from the adsorption of alkaline organics such as aniline and 4,4＇-MDA. The adsorbed alkaline organics could be cleaned up when the recovered catalyst was washed by methanol and DMF. Then the catalyst was effectively reused up to three cycles without much loss in its activity.

关键词： h4SiW12 O40@MIL- 100 ( Fe )Catalyst activation 4 4'-Methylenedianilinc synthesis Mukiphase reaction Stability

Structure and Thermochromic Property of a Silver(I) Complex Based on Dicyanamide and Phosphine Ligands

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Chinese journal of Structural Chemistry 2020年第7期39卷 1301-1306页

作者： XU Bo YANG Xiao-Dong kong Ling-Xue School of Chemistry and Chemical Engineering University of JinanJinan 250022China

A new silver(I)complex{Ag2(dppm)2[N(CN)2]}2[μ-N(CN)2]2(1)with chelate ligand bis(diphenylphosphino)methane(dppm)and bridging ligand dicyanamide(N(CN)2)was carefully synthesized and fully characterized by single-crystal X-ray crystallography,IR spectrometry,high-resolution mass spectrometry,thermal analysis and 1h *** to the crystal structure analysis,this complex could be considered as two binucleate moieties{Ag2(dppm)2[N(CN)2]}+linked by two bridging anionic ligands N(CN)2-.It exhibits thermochromic property in solid *** dependence of color or emission of substance on temperature is known as *** temperature luminescences of complex 1 are *** with the reduction of temperature from 298 K to 77 K,a noticeable emission enhancement as well as lifetime extension is observed.

关键词： silver complex crystal structure dicyanamide bis(diphenylphosphino)methane thermochromic property

Recent progress of CERN 39-cryogenic tracking detectors collaboration

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中国有色金属学会会刊：英文版 2006年第B1期16卷 137-140页

作者： j.hrknen helsinki Institute of Physics CERN /EPCH-1211 GenevaSwitzerland

Significant progress was made by the CERN RD39 collaboration in the development of super radiation-hard cryogenic silicon detectors for applications in experiments at LhC, in particular after its future luminosity upgrade. The detailed modeling shows that the electric field in irradiated silicon detectors can easily be manipulated by the filling state of two deep defect levels at cryogenic temperature. Advanced radiation hard detectors using charge or current injection and the current injected detectors(CID) were developed by RD39. The results show that CID detectors can be operated at the temperature of 100?200 K with much improved charge collection efficiency(CCE) as compared with RT operation. Future studies are developing ultra-hard cryogenic silicon detectors for the LhC upgrade, where the radiation hardness is required up to 1016 neq/cm2, at which trapping will limit the charge collection depth to the range of 20 to 50 μm regardless of the depletion depth. The key of our approach is to use freeze-out trapping to affect CCE.

关键词：欧洲原子能研究机构 CERN39协作组低温跟踪俘获粒子探测器研究进展

The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 51-61页

作者： h W A Riaz j Lin Department of Physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,which incorporates higher-order dispersive terms,is widely employed in the theoretical analysis of various physical *** this study,we explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated with the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly within the framework of *** visually understand the dynamics and solutions in the given example,we also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane waves and to understand the generation of periodic patterns within the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

Preparation and growth mechanism of nickel nanowires under applied magnetic field

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Nano-Micro Letters 2010年第2期2卷 134-138页

作者： j.Wang L.Y.Zhang P.Liu T.M.Lan j.Zhang L.M.Wei Eric Siu-Wai kong C.h.jiang Y.F.Zhang National Key Laboratory of Nano/Micro Fabrication Technology Key Laboratory for Thin Film and Microfabrication of the Ministry of Education Institute of Micro and Nano Science and Technology Shanghai Jiao Tong University School of Materials Science and Engineering Shanghai Jiao Tong University Zhongyuan University of Technology

Nickel nanowires with large aspect ratio of up to 300 have been prepared by a hydrazine hydrate reduction method under applied magnetic field. The diameter of nickel nanowires is about 200 nm and length up to 60 μm. The role of magnetic field on the growth of magnetic nanowires is discussed and a magnetic nanowire growth mechanism has been proposed. Nickel ions are firstly reduced to nickel atoms by hydrazine hydrates in a strong alkaline solution and grow into tiny spherical nanoparticles. Then, these magnetic particles will align under a magnetic force and form linear chains. Furthermore, the as-formed chains can enhance the local magnetic field and attract other magnetic particles nearby, resulting finally as linear nanowires. The formation and the size of nanowires depend strongly on the magnitude of applied magnetic field.

关键词： Nanowire growth mechanism Nickel nanowires Magnetic-field assisted synthesis

Effect of interlayer addition on microstructure and mechanical properties of NiTi/stainless steel joint by electron beam welding

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journal of Materials Science & Technology 2021年第2期61卷 16-24页

作者： h.Niu h.C.jiang M.j.Zhao L.j.Rong CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of ScienceShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China

NiTi/Stainless Steel(SS) sheets have been welded via a vacuum electron beam welding process, with three methods(offsetting electron beam to SS side without interlayer, adding Ni interlayer and adding Fe Ni interlayer), to promote mechanical properties of the Ni Ti/SS joints. The joints with different interlayers are all fractured in the weld zone near the Ni Ti side, which is attributed to the enrichment of intermetallic compounds including Fe2 Ti and Ni3 Ti. The fracture mechanisms of different joints are strongly dependent on the types of interlayers, and the joints without interlayer, adding Ni interlayer and adding Fe Ni interlayer exhibit cleavage fracture, intergranular fracture and mixed fracture composed of cleavage and tearing ridge, respectively. Compared with the brittle laves phase Fe2 Ti, Ni3 Ti phase can exhibit certain plasticity, block the crack propagation and change the direction of crack propagation. The composite structure of Ni3 Ti and Fe2 Ti will be formed when the Fe Ni alloy is taken as the interlayer, which provides the joint excellent mechanical properties, with rupture strength of 343 MPa.

关键词： NiTi Stainless steel Electron beam welding Interlayer Mechanical property

Effects of SiC Nanoparticle Content on the Microstructure and Tensile Mechanical Properties of Ultrafine Grained AA6063-SiC_(np) Nanocomposites Fabricated by Powder Metallurgy

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journal of Materials Science & Technology 2017年第9期33卷 1023-1030页

作者： X.Yao Z.Zhang Y.F.Zheng C.kong M.Z.Quadir j.M.Liang Y.h.Chen P.Munroe D.L.Zhang State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong University Electron Microscope Unit University of New South Wales School of Materials Science and Engineering University of New South Wales

Ultrafine grained AA6063-SiCnpnanocomposites with 1, 5 and 10 vol.% SiCnphave been fabricated by a novel powder metallurgy process. This process combines high energy ball milling of a mixture of 6063 alloy granules made from machining chips and Si C nanoparticles and thermomechanical powder consolidation by spark plasma sintering and hot extrusion. The microstructure and tensile mechanical properties of the samples were investigated in detail. Increasing the Si C nanoparticle content from 1 to 10 vol.%,the yield strength and ultimate tensile strength increased from 296 and 343 MPa to 545 and 603 MPa respectively, and the elongation to fracture decreased from 10.0%, to 2.3%. As expected, a higher Si C nanoparticle content generates a stronger inhibiting effect to grain growth during the thermomechanical powder consolidation process. Analysis of the contributions of various strengthening mechanisms shows that a higher Si C nanoparticle content leads to a higher contribution from nanoparticle strengthening, but grain boundary strengthening still makes the largest contribution to the strength of the *** the Si C nanoparticle content increased to 10 vol.%, the failure of the nanocomposite was initiated at weakly-bonded interparticle boundaries(IPBs), indicating that with a high flow stress during tensile deformation, the failure of the material is more sensitive to the presence of weakly-bonded IPBs.

关键词： Metal matrix nanocomposite Ultrafine grained material Powder metallurgy Tensile mechanical properties

g-C3N4-based nanocomposites for the photocatalytic degradation of VOCs:A review

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Progress in Natural Science:Materials International 2023年第4期33卷 407-424页

作者： huanran Miao Wenquan Zhang Tong Wang Zhimao Yang Chuncai kong Ministry of Education Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Advanced Functional Materials and Mesoscopic Physics School of Physics Xi'an Jiaotong University Shaanxi Coal Chemical Industry Technology Research Institute Co. Ltd.

With the rapid development of industries, the emission of volatile organic compounds(VOCs) produced by various chemical projects has been deteriorating the surrounding ecological environments and health of human being. Photocatalysis is an economic approach to solve environmental problems by using light irradiation to kick off chemical reactions under the action of photocatalysts. Owing to a narrow band gap, suitable redox potential,and high chemical stability, graphite carbon nitride(g-C3N4) has been widely adopted for performing cost-effective photocatalysis. however, the rapid recombination of electrons(e-) and holes(h+) on pure g-C3N4leads to its poor photocatalytic activity. To alleviate this shortcoming, g-C3N4has been reported in composite form(doped with other nanomaterials: carbon, metal, oxide, ion doping etc.) herein, we review detail research progress of four g-C3N4-based photocatalytic nanocomposites for the degradation of VOCs. Finally, we propose a scope for future research work for fabricating advanced g-C3N4-based heterostructure composite photocatalysts to treat VOCs admission.

关键词： g-C_3N_4 Nanocomposites Photocatalytic degradation VOCs