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Pt/TiO_(2) Nanosheets Array Dominated by {001} Facets with Enhanced Photocatalytic Activity

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Chinese Journal of Chemical Physics 2014年第5期27卷 530-534,I0003页

作者： Feng Li Zheng-ping Fu ya-lin lu CA5 Key laboratory of Materials for Energy Conversion Department of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

{001}facets dominated single crystalline anatase TiO_(2) nanosheet array(TNSA)was synthe-sized through an optimized organic solvothermal route on uorine-doped tin oxide *** field emission scanning electron microscopy images and X-ray diffraction patterns re-vealed that the{001}synthesized facets dominated TNSA exhibited much higher orientation than that synthesized by hydrothermal *** TNSAs were loaded with Pt nanoparti-cles in uniformly size by using a photodecomposition method,which were further con rmed by high resolution transmission electron microscopy(HRTEM).The HRTEM images also revealed that Pt nanoparticles preferred to deposit on{001}*** loading of Pt nanoparticles,the optical absorbance was significantly enhanced,while the photolumines-cence(PL)was *** photocatalytic activity of TNSA was signi cantly improved by Pt loading and reached the maximum with optimal amount of Pt *** optimal amount of Pt on{001}facets is far less than that on TiO_(2) nanoparticles,which may be attributed to the specific atom structure of reactive{001}facets.

关键词： Organic solvothermal route Photodecomposition TiO_(2) Nanosheet array {001}facet

Microstructure and mechanical properties of AZ91-Ca magnesium alloy cast by different processes

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China Foundry 2018年第4期15卷 263-269页

作者： xiao-yang chen yang zhang ya-lin lu xiao-ping li Key lab of advanced Materials Design and Additive Manufacturing of Jiangsu Province Jiangsu University of TechnologyChangzhou 213001China

The microstructure and mechanical properties of magnesium （Mg） alloys are significantly influenced by the casting process. In this paper, a comparative study on microstructure and mechanical properties at ambient and elevated temperatures of AZ91-2wt.% Ca （AZX912） Mg alloy samples prepared by gravity casting （GC）, squeeze casting （SC） and rheo-squeeze casting （RSC）, respectively, was carried out. The results show that mMg grains in SC and RSC samples are significantly refined compared to the GC sample. The average secondary dendritic arm spacing of AZX912 alloy samples decreases in the order of GC, SC and RSC. As testing temperature increases from 25 ~C to 200 ~C, strength of AZX912 alloy samples is reduced, while their elongation is increased continuously. Compared to GC and SC processes, RSC process can improve the mechanical properties of AZX912 alloy at both ambient and elevated temperatures. The enhancement of mechanical properties of RSC sample over GC and SC samples mainly results from grain refinement in the as-cast microstructure of AZX912 alloy.

关键词： magnesium alloys casting process microstructure mechanical properties

Microstructure evolution and mechanical properties of rheo-squeeze casting AZ91-Ca alloy during heat treatment

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China Foundry 2017年第6期14卷 485-491页

作者： yang Zhang Xiao-ping Li Shun-ping Sun ya-lin lu Guo-hua Wu School of Materials Engineering Jiangsu University of Technology Changzhou 213001 China National Engineering Research Center of Light Alloy Net Forming Shanghai Jiao Tong University Shanghai 200240 China

The rheo-squeeze casting(RSC)process is a newly-developed casting process for high-performance *** order to further improve the mechanical properties of magnesium alloys,AZ91-2wt.%Ca(AZX912)alloy was prepared by the RSC process and then subjected to heat *** microstructure evolution and mechanical properties of AZX912 alloy during heat treatment were *** was found that during solid solution treatment at 410°C,β-Mg_(17)Al_(12) phase with low melting point dissolves intoα-Mg matrix,while the connected network-like Al_2Ca phase with high melting point tends to separate gradually,and the tips of Al_2Ca phase is partially *** the increase of solid solution time,the yield strength(YS)of AZX912 alloy decreases gradually while the ultimate tensile strength(UTS)and elongation to failure(E_f)increase *** ageing at 225°C promotes the precipitation ofβ-Mg_(17)Al_(12) phase in the matrix of AZX912 *** hardness reaches the peak after ageing for 96 h and the increase in hardness is about 24.8%.The precipitation ofβ-Mg_(17)Al_(12) phase during ageing treatment is beneficial to YS but harmful to E_*** mechanism of microstructure evolution during heat treatment and its effect on mechanical properties are discussed.

关键词： magnesium alloys semisolid processing heat treatment microstructure mechanical properties

Effects of oxygen vacancy concentration and temperature on memristive behavior of SrRuO3/Nb:SrTiO3 junctions

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Chinese Physics B 2019年第8期28卷 324-328页

作者： Zhi-Cheng Wang Zhang-Zhang Cui Hui Xu Xiao-Fang Zhai ya-lin lu Hefei National Laboratory for Physical Sciences at Microscale University of Science and Technology of ChinaHefei 230026China National Synchrotron Radiation Laboratory University of Science and Technology of ChinnHefei 230026China Synergy Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China

Metal/semiconductor memristive heterostructures have potential applications in nonvolatile memory and computing *** enhance the performance of the memristive devices,it requires a comprehensive engineering to the metal/semiconductor *** in this paper,we discuss the effects of oxygen vacancies and temperature on the memristive behaviors of perovskite-oxide Schottky junctions,each consisting of SrRuO3 thin films epitaxially grown on Nb:SrTiO3 *** oxygen partial pressure and laser fluence are controlled during the film growth to tune the oxygen defects in SrRuO3 films,and the Schottky barrier height can be controlled by both the temperature and oxygen *** resistive switching measurements demonstrate that the largest resistance switching ratio can be obtained by controlling oxygen vacancy concentration at lower *** suggests that reducing Schottky barrier height can enhance the resistive switching performance of the SrRuO3/Nb:SrTiO3 *** work can conduce to the development of high-performance metal-oxide/semiconductor memristive devices.

关键词： memristor oxygen vacancy Schottky barrier

Characteristics and geological significance of the stress state of the lithosphere in the Qinghai-Tibetan Plateau and its neighboring areas

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Science China Earth Sciences 2024年第6期67卷 1836-1855页

作者： Qianwen ZHANG ya XU Wei CHU Shupeng lu Key Lab of Petroleum Resource Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The present-day lithospheric stress state of the Qinghai-Tibetan Plateau and neighboring areas is controlled by both the lithosphere itself and the underlying *** other words,the stress is affected by the gravitational potential energy(GPE)difference caused by the change in the density distribution within the lithosphere and the drag force on the base of the lithosphere caused by mantle *** study of the lithospheric stress state plays an important role in further understanding the dynamic background and mechanism for the evolution of the Qinghai-Tibetan *** this study,the Crust1.0 crustal density model combined with the S40RTS mantle shear wave velocity variation model was used to calculate the *** EGM2008gravity field model was used to calculate the drag force from mantle convection at the base of the *** lithospheric and joint stress fields of the two sources were obtained by solving the force balance under the thin sheet *** way,we could comprehensively analyze the characteristics of the stress state within the *** regions were classified according to the GPE stress field,mantle drag force stress field,the relative magnitude of the two stress fields,and correlation between the two stress fields and surface *** lithospheric stress fields of the Tarim Basin and other stable blocks are mainly controlled by the GPE *** lithospheric stress field in the collision zone between the Indian Plate and the QinghaiTibetan Plateau is predominantly controlled by the deep mantle drag *** lithospheric stress field in the interior of the Plateau is controlled by both GPE and mantle *** correlation between the lithospheric stress field and surface deformation at the southeast margin of the Qinghai-Tibetan Plateau is *** is hypothesized that the presence of lower crustal flow with lower effective viscosity leads to crust-mantle decoupling,and the mantle drag force has a weaker influe

关键词： Qinghai-Tibetan Plateau Gravitational potential energy Mantle convection Lithospheric deviatoric stress field GPS strain rate field

Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： Yong-Zhi lin lu-Kun Feng ya-Dong Li Chao-Fan Chang Cai-Zhen Zhu Ming-Liang Wang Jian Xu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of *** approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric *** validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric ***,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and *** resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in *** findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT

Microstructure and mechanical properties of as-extruded Mg-Sn-Zn-Ca alloy with different extrusion ratios

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Transactions of Nonferrous Metals Society of China 2018年第11期28卷 2191-2199页

作者： yang ZHANG Xiao-yang CHEN ya-lin lu Xiao-ping LI School of Materials Engineering Jiangsu University of TechnologyChangzhou 213001China School of Mechanical Engineering Jiangsu University of TechnologyChangzhou 213001China

The effect of extrusion ratio on microstructure and mechanical properties of as-extruded Mg-6Sn-2Zn-1Ca （TZX621）（mass fraction, %） alloy was investigated. It is found that incomplete dynamic recrystallization （DRX） took place in as-extrudedTZX621 alloy. As the extrusion ratio was increased from 6 to 16, both fraction of un-DRXed grains and average size of DRXedgrains in as-extruded TZX621 alloy decreased and the basal texture was weakened. Coarse CaMgSn phase was broken into particlesand fine Mg2Sn phase precipitated from α-Mg matrix during hot extrusion. Yield strength, ultimate tensile strength and elongation ofas-extruded TZX621 alloy with extrusion ratio of 16 reached 226.9 MPa, 295.6 MPa and 18.1%, which were improved by 36.0%,17.7% and 13.5%, respectively, compared to those of as-extruded TZX621 alloy with extrusion ratio of 6.

关键词： Mg-Sn alloy extrusion ratio microstructure texture mechanical properties

Comprehensive study on the spatial distribution of heavy metals and their environmental risks in high-sulfur coal gangue dumps in China

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Journal of Environmental Sciences 2024年第2期136卷 486-497页

作者： Yingbo Dong Huan lu Hai lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in *** spatial distribution and environment risk assessment are extremely important for the management and remediation of *** soil samples were collected from the high-sulfur CG site in northern China and analyzed for six *** results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment *** semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of ***,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more *** spatial autocorrelation indicated that all HMs had strong spatial *** BCR sequential extraction was employed to qualify the geochemical fractions of *** data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)*** correlation analysis showed that pH was the main control factor affecting the non-residue fractions of ***,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of ***,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.

关键词： High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment

Robust textile-based spoof plasmonic frequency scanning antenna for on-body IoT applications

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Science China(Information Sciences) 2024年第8期67卷 269-284页

作者： Zhao-Min CHEN Jun-lin ZHAN Hao CHEN ya LI Hongjun HE Wu yaNG Zhen-Guo LIU Wei-Bing lu State Key Lab of Millimeter Waves School of Information Science and EngineeringSoutheast University Center for Flexible RF Technology Frontiers Science Center for Mobile Information Communication and SecuritySoutheast University Future Research Laboratory China Mobile Research Institute Purple Mountain Laboratories

Securing a comfortable, wearable compact frequency beam scanning antenna(FBSA) with robustness to deformation, low specific absorption rate(SAR), and good coverage of the surrounding environment for Internet of Things(IoT) applications, such as on-body navigation and wireless communication is an emerging challenge. In this work, a robust textile-based spoof plasmonic frequency scanning antenna utilizing higher-order modes is presented, which is also robust to deformation caused by the activities of the human body. The innovative design of the element ensures the high-efficiency transmission of the fundamental mode of spoof surface plasmon polaritons(SSPP) structure, providing the potential of being a multifunctional composite device in the compact on-body network. Besides, an artificial magnetic conductor(AMC) is designed underneath the SSPP structure, obtaining a low SAR value(0.113 W/kg), which ensures the safety of users. As a practical realization of this concept, a textile-based spoof plasmonic antenna was fabricated in the microwave regime and the performed experimental results show the proposed antenna has a single-beam radiation characteristic with a 70° beam scanning angle range when the frequency is 4.7–6.0 GHz with a high average realized gain of 13.15 dBi. And it still maintains a steady performance when faced with structure deformation, which proves its robustness. Wireless communication quality experiments are performed to demonstrate the proposed antenna can measure the angles of targets and realize wireless signal transmission to specific targets as the frequency varies, it may find great potential in the field of on-body IoT applications.

关键词： frequency beam scanning antenna (FBSA) Internet of Things (IoT) on-body communication spoof surface plasmon polaritons (SSPP) textile-based antenna

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