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Journal of Materials Science & Technology 2011年第9期27卷 856-860页

作者： b. Xu W.P. Tong c.Z. Liu H. zhang L. Zuo J.c. He Key Laboratory of National Education Ministry for Electromagnetic Processing of Materials Northeastern University Shenyang 110004 China Department of Materials Engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034 China

The effect of magnetic field on the growth behavior of compound layer was examined at the interface between the solid cu and liquid AI during reactive diffusion. It was found that the thickness of compound layer was reduced by the high magnetic field. The growth activation energy in β, γ1 and ε2 layers under a high magnetic field was larger than those in non magnetic circumstances, the increment percentage being 4.8%, 13.3% and 5.5%, respectively.

关键词： Diffusion Activation energy High magnetic field Al cu

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当前的民族过程——关于苏联新宪法的讨论

世界民族 1991年第6期 67-71页

作者： Ю.В.布朗利 c.b.切什科白萍

一、概况由于意识形态、政治和社会-经济的严重扭曲而产生的苏联社会的危机,使苏联各民族的民族发展、族际关系的状态遭受了严重的损失。这同样也在加深危机,阻障社会的进步改革,产生离心的和分解的倾向,这些倾向威胁着苏联作为一个主... 详细信息

一、概况由于意识形态、政治和社会-经济的严重扭曲而产生的苏联社会的危机,使苏联各民族的民族发展、族际关系的状态遭受了严重的损失。这同样也在加深危机,阻障社会的进步改革,产生离心的和分解的倾向,这些倾向威胁着苏联作为一个主权国家的完整甚至于生存。在斯大林主义时期及稍后,曾允许直接侵犯各民族的权利,各加盟共和国的少数民族受害尤甚。最终,苏联的民族国家制度本身不仅没有保证各民族的平等权利,而且在很大程度上阻碍了它的保证作用。

关键词：各民族族际关系土著民族苏联宪法国家制度民族过程民族发展民族集团少数民族民族主义

Fabrication of carbon-supported Al2O3 nanoparticles via spontaneous cross-linking to enhance selective hydrogenation of furfural

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Journal of Energy chemistry 2025年第1期100卷 612-620页

作者： Weiwei Yu Xinbao zhang Hongyu chen Yanan Wang Shaoguo Li Fucun chen Zhenni Liu Xiujie Li Xiangxue Zhu State Key Laboratory of catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of c=c over c=***,a novel Al2O3/c-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al2O3nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and *** obtained carbon-supported Al2O3hybrid catalyst has a high ratio （31%） of Al species in pentahedral-coordinated *** introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of c=O and the accessibility of active *** the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al2O3/c-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-***,Al2O3/c-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on *** work provides an innovative and facile strategy for fabrication of carbon-supported Al2O3hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.

关键词： Selective hydrogenation Furfural Furfuryl alcohol cross-linking MPV route

Interactions of sulfuric acid with common atmospheric.b.ses and organic acids: Thermodynamics and implications to new particle formation

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Journal of Environmental Sciences 2020年第9期32卷 130-140页

作者： Yunfeng Li Haijie zhang Qingzhu zhang Yisheng Xu Alexey b.Nadykto Environment Research Institute Shandong UniversityQingdao 266237China State Key Laboratory of Environmental criteria and Risk Assessment Chinese Research Academy of Environmental ScienceBeijing 100012China Department of Applied Mathematics Moscow State University of Technology“Stankin”Moscow 127994Russia

Interactions of the three common atmospheric.b.ses,dimethylamine((cH3)2 NH),methylamine(cH3 NH2),ammonia(NH3),all considered to be efficient stabilizers of binary clusters in the Earth’s atmosphere,with H2 SO4,the key atmospheric precursor,and 14 common atmospheric organic acids(cOAs)(formic,acetic,oxalic,malonic,succinic,glutaric acid,adipic.b.nzoic,phenylacetic,pyruvic,maleic acid,malic,tartaric and pinonic acids)have been studied using the density functional theory(DFT)and composite high-accuracy G3 MP2 *** thermodynamic stability of mixed(cOA)(H2 SO4),(cOA)(b1),(cOA)(b2)and(cOA)(b3)dimers and(cOA)(H2 SO4)(b1),(cOA)(H2 SO4)(b2)and(cOA)(H2 SO4)(b3)trimers,where b1,b2 and b3 refer to(cH3)2 NH,cH3 NH2 and NH3,respectively,have been investigated and their impacts on the thermodynamic stability of clusters containing H2 SO4 have been *** investigation shows that interactions of H2 SO4 with GOA,(cH3)2 NH,cH3 NH2 and NH3 lead to the formation of more stable mixed dimers and trimers than(H2 SO4)2 and(H2 SO4)2(base),respectively,and emphasize the importance of common organic species for early stages of atmospheric *** also show that although amines are generally confirmed to be more active than NH3 as stabilizers of binary clusters,in some cases mixed trimers containing NH3 are more stable thermodynamically than those containing cH3 *** study indicates an important role of cOA,which coexist and interact with that H2 SO4 and common atmospheric.b.ses in the Earth atmosphere,in formation of stable prenucleation clusters and suggests that the impacts of cOA on new particle formation(NPF)should be studied in further details.

关键词： bases particle atmospheric

Numerical investigation into the effect of backfilling on coal pillar strength in highwall mining

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International Journal of Mining Science and Technology 2018年第2期28卷 281-286页

作者： Mo S. canbulat I. zhang c. Oh J. Shen b. Hagan P. School of Mining Engineering The University of New South Wales cSIRO Energy QCAT1 Technology Court

This paper attempts to quantify the effect of backfilling on pillar strength in highwall mining using numerical modelling. calibration against the new empirical strength formula for highwall mining was conducted to obtain the material parameters used in the numerical modelling. With the obtained coal strength parameters, three sets of backfill properties were investigated. The results reveal that the behavior of pillars varies with the type and amount of backfill as well as the pillar width to mining height ratio(w/h). In case of cohesive backfill, generally 75% backfill shows a significant increase in peak strength, and the increase in peak strength is more pronounced for the pillars having lower w/h ratios. In case of noncohesive backfill, the changes in both the peak and residual strengths with up to 92% backfill are negligible while the residual strength constantly increases after reaching the peak strength only when 100%backfill is placed. based on the modelling results, different backfilling strategies should be considered on a case by case basis depending on the type of backfill available and desired pillar dimension.

关键词： Highwall mining backfill coal pillar Strength Numerical modelling

crystal Structure and Magnetic Studies of a New Nitronyl Nitroxide compound

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chinese chemical Letters 2000年第8期11卷 749-752页

作者： Ding, L zhang, DQ zhang, b Zhu, Db chinese Acad Sci Ctr Mol Sci Inst Chem Organ Solids Lab Beijing 100080 Peoples R China

compound 1 was first synthesized and characterized. Its crystal structure and magnetic property were determined and investigated. Discussion about the molecule packing in crystal and the macroscopic magnetism was also... 详细信息

关键词： nitronyl nitroxide crystal structure spin density magneto-structural relationship

INFLUENcES OF NEODYMIUM ON MAGNETIc cHARAcTERISTIcS OF ELEcTROPLATING coNdNiMnP FILMS

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Acta Metallurgica Sinica(English Letters) 2005年第2期18卷 149-152页

作者： H.c.Jiang W.L.zhang J.P.zhang W.X.zhang b.Peng S.Q.Yang SchoolofMicroelectronicsandSolidElectronics UniversityofElectronicScienceandTechnologyofChinaChengdu610054China

In order to improve the performances of electroplating permanent magnetic films, neodymium is introduced into the electroplating coNiMnP permanent magnetic films. The influences of the neodymium content are also investigated by varying Ndcl3 plating bath concentration. The neodymium-doped films are analyzed by energy dispersive spectrum (EDS), vibrating sample magnetometer (VSM) and magnetic force microscope (MFM). The experimental results show that high magnetic performances of coNdNiMnP permanent magnetic films with vertical anisotropy could be fabricated with current density 5mA/cm2 at room temperature. With the increasing of neodymium contents, the magnetic properties of films were improved. However when neodymium contents exceeded 3.5wt%, the magnetic properties of films are not improved any more. The increase of film magnetic properties results from the ferromagnetic-coupling between light rare earth element-neodymium and transition metal element-c.b.lt.

关键词： coNdNiMnP permanent magnetic film magnetic property electroplating vertical anisotropy

Seasonal and Spatial Variability of Microparticles in Snowpits on the Tibetan Plateau, china

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Journal of Mountain Science 2010年第1期7卷 15-25页

作者： zhang Yulana KANG Shichang zhang Qianggong cONG Zhiyuan zhang Yongjun GAO Tanguang Laboratory of Tibetan Environment changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China State Key Laboratory of cryospheric Sciences ChineseAcademy of Sciences Lanzhou 730000 China Graduate University of chinese Academy of Sciences Beijing 100049 China

The work presents microparticle concentrations in snowpits from the East Rongbuk Glacier on Mt. Qomolangma (Everest) (ER) (28.02°N, 86.96°E, 6536 m a.s.l.), the Zhadang Glacier on Mt. Nyainqentanglha (NQ) (30.47°N, 90.65°E, 5800m a.s.l.), and the Guoqu Glacier on Mt. Geladaindong (GL) (33.95°N, 91.28°E, 5823m a.s.l.) over the Tibetan Plateau (TP). Variations of microparticle and major ions (e.g. Mg2+, ca2+) concentrations in snowpits show that the values of the microparticles and ions in the non-monsoon seasons are much higher than those in the monsoon seasons. Annual flux of microparticle deposition at ER is lower than those at NQ and GL, which could be attributed to the long distance away from the possible dust source regions as well as the elevation for ER higher than the others. compared with other remote areas, microparticle concentrations in the southern TP are much lower than those in the northern TP, but still much higher than those in Greenland and Antarctica. The seasonal and spatial microparticle variations are clearly related to the variations of atmospheric circulation according to the air mass 5-day backward trajectory analyses of HYSPLIT Model. Resultingly, the high microparticle values in snow are mainly attributed to the westerlies and the strong dust storm outbreaks on the TP, while the monsoon circulation brings great amount of precipitation from the Indian Ocean, thus reducing in the aerosol concentrations.

关键词： Microparticle seasonal change spatialvariation snowpits Tibetan Plateau

Effects of Y content and temperature on the damping capacity of extruded Mg-Y sheets

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Journal of Magnesium and Alloys 2019年第3期7卷 522-528页

作者： Y.T.Tang c.zhang L.b.Ren W.Yang D.D.Yin G.H.Huang H.Zhou Y.b.zhang Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengduSichuan 610031PR China Nano and Heterogeneous Materials center School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094PR China

The damping behavior of extruded Mg-xY(x=0.5,1.0,3.0 wt.%)sheets were investigated in detail concerning the effects of Y addition and temperature,and the relationship between damping capacity and yield strength was *** room temperature(RT),with Y content increasing from 0.5%to 3.0%,the damping capacity(Q-1)significantly decreased from 0.037 to *** all the studied sheets,the relationship between strain amplitude and Q-1 fitted well with the Granato and Liicke(G-L)dislocation damping *** temperature increased,the G-L plots deviated from linearity indicating that the dislocation damping was not the only dominate mechanism,and the grain boundary sliding(GbS)could contribute to damping ***,the Q-1 increased remarkably above the critical temperature,and the critical temperature increased significantly from 50℃ to 290℃ with increasing Y contents from 0 to 3.0wt.%.This result implied that the segregation of Y solutes at grain boundary could depress the GbS,which was consistent with the recent finding of segregation tendency for rare-earth *** extruded Mg-IY sheet exhibited slightly higher yield strength(Rp0.2)and Q-1 comparing with high-damping Mg-0.6Zr at *** an elevated temperature of 325℃,the Mg-IY sheet had similar Q-1 but over 3 times larger Rp0.2 than that of the pure *** present study indicated that the extruded Mg-Y based alloys exhibited promising potential for developing high-performance damping alloys,especially for the elevated-temperature application.

关键词： Extruded sheets Mg-Y alloys Damping capacity Granato and Lücke model Elevated temperature

Regulation of thermoelastic properties of concave-packaged DNA adsorption films and its relevant microcantilever detection signals

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Acta Mechanica Sinica 2021年第4期37卷 705-711,I0004页

作者： c.X.Wu N.H.zhang c.Y.zhang J.Z.Wu School of Mechanics and Engineering Science Shanghai UniversityShanghai 200444China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsShanghai 200072China

The packing patterns have close correlation with the thermoelastic properties of DNA adsorption films and the relevant detection signals of *** this paper,we investigate the influence of packing patterns on the thermoelastic properties of DNA adsorption films,the detection signals of microcantilevers and their temperature ***,the Parsegian's empirical potential based on a mesoscopic liquid crystal theory is employed to describe the interaction energy among coarse-grained DNA cylinders;then,the thought experiment method and the force balance method of nonlinear elastic network nodes are combined to characterize the elastic modulus,prestress and thermal expansion coefficient of DNA adsorption films;finally,based on an effective macroscopic continuum model for DNA microbeam deformation,we study the microcantilever resonance frequency shifts caused by DNA adsorptions and the temperature effect on the microcantilever static deflections,*** show that,compared with the convex-packaged,the re-entrant honeycomb packing pattern endows DNA adsorption films with a larger adjustable range of the elastic modulus and prestress,so as to make DNA-microcantilevers having an enhanced dynamic detection signal whereas a weaker response to temperature *** results are expected to provide a new option for the regulation design of DNA composite materials and microbeam sensors.

关键词： DNA-microbeam Packaging pattern Elastic property Thermal expansion coefficient Detection signal