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First-principles calculation of Aun@(ZnS)(42)(n=6-16)hetero-nanostructure system

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Rare Metals 2020年第10期39卷 1165-1173页

作者： Han-Yue Zhao Qing Liu Xiao-xu Wang Jin-Rong Huo Lu Li ping Qian Yan-jing Su Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Department of Physics University of Science and Technology BeijingBeijing 100083China Corrosion and Protection Center Key Laboratory for Environmental Fracture(MOE)University of Science and Technology BeijingBeijing 100083China

The structure stability and electronic and optical properties of a series of Au@ZnS core-shell nanocomposites with different sizes were investigated theoretically by first-principle calculation based on density functional theory(DFT).A series of Aun@(ZnS)(42)structures with different n values from 6 to 16 were optimized and *** on the core-shell interaction energy and second-order difference of total energy of these structures,it is found that Au(13)@(ZnS)(42)turns out to be the most stable *** on the model of Au(13)@(ZnS)(42),the density of state and charge density difference were studied and provided a deeper understanding of the electronic structures of Au@*** the other hand,absorption coefficient and dielectric function were investigated to study the optical *** is found that an optical absorption peak appears in visible-light region,indicating that the photo-catalytic can be improved prominently due to the optical redshift to visible-light region when forming core-shell structure from ZnS *** the redshift phenomenon accords well with ***,the electronic structure further confirms the existence of redshift of optical absorption spectrum.

关键词： Core-shell structure Density functional theory(DFT) Electronic structure Optical properties Redshift phenomenon

The Change of Orientation Relationships Between Austenite and α'-Martensite During Deformation in High Manganese TRIP Steel

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 289-294页

作者： Hai-Yan Yang jing Li ping Yang School of Materials Science and Engineering University of Science and Technology Beijing

In situ observation of electron backscattering diffraction technique was used to evaluate the orientation relationships between austenite and α′-martensite（α′-M） for high manganese transformation-induced plasticity *** was noted that different from the thermal martensite,which well obeyed K-S relationship with austenite,the orientation relationship between deformation-induced α′-M with austenite changed during deformation,namely K-S and N-W relations *** clear differences existed between α′-M variants with two kinds of relationships in terms of martensitic orientation,shape and the misorientation between α′-M *** this phenomenon happened in almost all austenitic grains with different orientations investigated in this *** atom displacement mechanism through conjugate complex slips of partial dislocations in the distorted fcc lattice was applied in this article to interpret the coexistence of K-S and N-W relationships.

关键词： In situ observation Orientation relationship Electron backscattered diffraction technique(EBSD) Martensitic transformation High manganese TRIP steel

Calculation of Hugoniot properties for shocked nitromethane based on the improved Tsien's EOS

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Acta Mechanica Sinica 2010年第3期26卷 365-370页

作者： Bo Zhao Ji-ping Cui jing Fan Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of SciencesBeijing 100190 China

We have calculated the Hugoniot properties of shocked nitromethane based on the improved Tsien＇s equa- tion of state （EOS） that optimized by ＂exact＂ numerical molecular dynamic data at high temperatures and pressures. Comparison of the calculated results of the improved Tsien＇s EOS with the existed experimental data and the direct simu- lations show that the behavior of the improved Tsien＇s EOS is very good in many aspects. Because of its simple analytical form, the improved Tsien＇s EOS can be prospectively used to study the condensed explosive detonation coupling with chemical reaction.

关键词： Equation of state High pressures andtemperatures Shocked nitromethane Hugoniot properties

Strengthening poly(2-hydroxyethyl methacrylate) hydrogels using biochars and hydrophobic aggregations

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International Journal of Smart and Nano Materials 2022年第4期13卷 561-574页

作者： ping Zhang Ziyi xu Zhiying Wu ping xu Canhui Yang Shenzhen Key Laboratory of Soft Mechanics&Smart Manufacturing Department of Mechanics and Aerospace EngineeringSouthern University of Science and TechnologyShenzhenP.R.China Department of Chemistry City University of Hong KongHong KongP.R.China Department of Respiratory and Critical Care Medicine Peking University Shenzhen HospitalShenzhenGuangdongP.R.China

As the first version of synthetic hydrogel,poly(2-hydroxyethyl methacrylate)hydrogels have found broad ***,their poor mechanical performances have been longstanding hurdles for practical ***,we report on strengthening the poly(2-hydroxyethyl methacrylate)hydro-gels with biochar nanoparticles and hydrophobic aggregations,which are induced by solvent exchange and reinforced by *** the vast anchoring points on the multifunc-tional surfaces of the biochar nanoparticles and the aggregates formed between poly(2-hydroxyethyl methacrylate)chains engender strong and dissipative physical *** result-ing hydrogels exhibit marked mechanical properties,encom-passing high stretchability~7,high fracture toughness~1360 J m−2,high elastic modulus~180 kPa,low friction coefficient~0.2,self-recovery,and ***,we demonstrate the versatility of the proposed strategy by using water/ionic liquid binary solvent as the sol-vent system,Laponite as the nano-reinforcement,and dryanneal as the hydrophobic aggregation enhancer to synthesize mechanically robust ***(2-hydroxyethyl methacry-late)hydrogels of superior mechanical properties are expected to enable previously inaccessible applications in biomedicine and engineering.

关键词： Hydrogel PHEMA mechanical properties biochar hydrophobic aggregation

Elastoplastic Analysis of Circular Tunnel in Saturated Ground Under Different Load Conditions

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Computers, Materials & Continua 2020年第1期62卷 179-197页

作者： Panpan Zhai ping xu College of Water Conservancy&Environmental Engineering Zhengzhou UniversityZhengzhou450001China National Local Joint Engineering Laboratory of Major Infrastructure Testing and Rehabilitation Technology Zhengzhou450001China

When a tunnel is excavated below the groundwater table,groundwater flows in through the excavated wall of the tunnel and seepage forces act on *** forces significantly affect the ground reaction curve,which is defined as the relationship between the internal pressure and radial displacement of the tunnel *** study investigates analytical solutions for seepage forces acting on the lining of a circular tunnel under steady-state groundwater *** the tunnel’s construction or service period and boundary conditions,the direction of maximum principal stress changes,and the input stress of the Mohr-Coulomb criterion *** stress distribution and yield range of the surrounding soils and linings are *** first,second,and third critical inner pressures are defined and *** influence of the seepage field on the plastic radius,first critical pressure,and stress distribution of the tunnel is *** is shown that during the construction period,the seepage force promotes the expansion of the yield area,whereas during the service period,the opposite is the *** first critical pressure increases nearly linearly with the distant water *** radial stress distribution decreases clearly in comparison with that when the seepage force is not considered,and the reduction is more prominent when internal pressure *** tangential stress distribution increases clearly compared with that when the seepage force is not considered.

关键词： Tunnel lining surrounding soils elastoplastic analysis critical pressure plastic radius seepage force

Domains and enrichment mechanism of the lithospheric mantle in western Yunnan: A comparative study on two types of Cenozoic ultrapotassic rocks

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Science China Earth Sciences 2005年第3期48卷 326-337页

作者： XIA ping xu Yigang Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Geochemical comparison of two suites of Cenozoic potassic volcanic rocks in western Yunnan reveals the existence of two mantle domains beneath this region, which corre- spond to their respective tectonic affinity. The Erhai ultrapotassic rocks (42—24Ma) in western Yangtze Craton are characterized by LILE enrichment, HFSE depletion, low TiO2 content (2%), low initial 87 Sr/86Sr (0.7041—0.7060) and positive εNd (5.46—7.03). These features resemble the typical intraplate potassic rocks around the world. These rocks are thus interpreted as melting products of a fertile garnet lherzolitic source which has been infiltrated by small-volume, asthenosphere-derived silicate melts. The temporal and spatial distribution of these two types of K-rich rocks cannot be explained by any unified tectonic model. It is proposed that the Oligocene magmatism in the Erhai area may have resulted from convective thinning of the thickened lithosphere, whereas the post-Miocene volcanism in the Maguan area was related to the opening of South China Sea.

关键词： ultrapotassic magma, geochemistry, magmatic evolution, lithospheric mantle, western Yunnan.

Penetration and lubrication evaluation of vegetable oil with nanographite particles for broaching process

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Friction 2021年第6期9卷 1406-1419页

作者： Ming xu Xin YU jing NI School of Mechanical Engineering Hangzhou Dianzi UniversityHangzhou 310018China

With increasing environmental concerns,the substitution of mineral oil-based cutting fluid has become an urgent *** vegetable soybean oil as base fluid,nanofluid cutting fluids(NFCFs)were prepared by adding different weight concentrations of nanographite particles(NGPs),and their penetration and lubrication performances were studied.A novel simulated tool-chip slit with micrometersized geometry was manufactured to evaluate and quantify the penetration rate of the NFCFs by image analysis ***,a large number of comparative experiments on the closed-type broaching machine were carried out to compare the performance of the proposed NFCFs and a commercial cutting fluid in terms of cutting force,workpiece surface roughness,and metal *** is found that there is an optimal NGP concentration in NFCF for practical cutting *** the concentration of NGP is 0.4 wt%,the broaching process lubrication exhibits an ideal mixed lubricate state,resulting in minimal friction resistance,and thus,both the cutting force and chip curling angle reach their corresponding best ***,the proposed NGP-based vegetable-oil cutting fluid exhibits excellent environmentfriendliness and low-cost consumption in the minimal quantity lubrication(MQL)method;this demonstrates its potential for replacing the traditional broaching cutting fluid.

关键词： cutting fluid vegetable oil nano-graphite particle penetration broaching

Visualizing nanopore blinkings in parallel:a high-throughput nanopore array potential for ultra-rapid DNA sequencing

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Science Bulletin 2015年第23期60卷 2067-2068页

作者： jing-Juan xu State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences School of Chemistry and Chemical EngineeringNanjing University

Upon finishing the sequencing of the first complete human genome in 2004[1],the demand for fast DNA reading with less than$1,000 has been fueled by the ever-increasing awareness for personalized medicine and clinical diagnosis[2,3].Plenty of sequencing techniques,from the original Sanger sequencing method to novel sequencing-by-synthesis technologies(Roche,Solexa,SOLi D,etc.)[3],have been developed rapidly in past decades,which are sug-

关键词： DNA测序纳米孔阵列高通量可视化超快速人类基因组测序平行临床诊断

A Novel 3D Extended Network Cobalt Paradodecatungstate:Synthesis,Characterization and Crystal Structure of [Co(H_2O)_5]_2[Co(H_2O)_4]_3[H_2W_(12)O_(42)]·11H_2O

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1167-1174页

作者： WANG jing-ping REN Qing ZHAO Jun-Wei NIU jing-Yang Institute of Molecular and Crystal Engineering College of Chemistry and Chemical Engineering Henan University Kaifeng Henan 475001 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhcu Fujian 350002 China

A cobalt paradodecatungstate [Co（H2O）5]2[Co（H2O）4]3[H2W12O42]·11H2O has been successfully synthesized and structurally characterized by X-ray crystallography. Structure analysis indicates that the title compound is of monoclinic, space group P21/n, with a = 13.449（3）, b = 19.585（4）, c = 13.990（3） °A, = 113.79（3）°, V = 3371.8（12） °A^3, Z = 2, R = 0.0519 and wR = 0.1242. The title compound exhibits a novel 3D extended network structure constructed by interconnecting the paradodecatungstate polyanion [H2W12O42]^10- clusters and cobalt^11 coordination ions.

关键词： paradodecatungstate polyoxometalate cobalt Keggin structure