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Properties and microstructure of oxide dispersion strengthened tungsten alloy prepared by liquid-phase method:a review

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Tungsten 2023年第4期5卷 481-502页

作者： Liu-Jie Xu zhou Li Fang-Nao Xiao Yun-Chao Zhao Yu-Cheng zhou Shi-Zhong Wei National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials Henan University of Science and TechnologyLuoyang471003China Henan Key Laboratory of High-temperature Structural and Functional Materials Henan University of Science and TechnologyLuoyang471003China College of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing201116China

The addition of the second phase into tungsten can significantly refine the grain size of tungsten alloys,and also play a role in dispersion strengthening,thus improving the properties of tungsten *** a preparation method of tungsten alloy powder,liquid-phase method avoids the disadvantage of mechanical alloying,and the obtained powder composition is accurate and controllable,with high purity and excellent *** present,the second phase particles used for dispersion strengthening tungsten alloys are mainly composed of *** particles can be synthesized and precipitated in nitrate solution through in situ chemical reaction,and are uniformly distributed in composite powder by mixing and ***,the oxide dispersion strengthened tungsten alloy(ODS-W)was obtained by reduction and ***-phase methods for preparing ODS-W alloys include azeotropic distillation,sol-gel methods,freeze-drying,hydrothermal synthesis,spray-drying,*** this paper,several liquid-phase methods for preparing tungsten alloy composite powder precursors are reviewed,and their latest research progresses are *** addition,the morphologies and properties of tungsten alloys prepared by different methods are compared,which provides guidance for preparing high-performance tungsten alloys.

关键词： Tungsten alloy ODS-W Liquid-phase method Microstructure Property

Yearly variation in character istics and health risk of polycyclic aromatic hydrocarbons and nitro-PAHs in urban shanghai from 2010-2018

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Journal of Environmental Sciences 2021年第1期33卷 72-79页

作者： Lu Yang Xuan Zhang Wanli Xing Quanyu zhou Lulu Zhang Qing Wu Zhijun zhou Renjie Chen Akira Toriba Kazuichi Hayakawa Ning Tang Graduate School of Medical Sciences Kanazawa UniversityKakuma-machiKanazawa920-1192Jjapan School of Public Health Fudan UniversityShanghai 200032China Institute of Medical Pharmaceutical and Health SciencesKanazawa UniversityKakuma-machiKanazawa920-1192Japan Institute of Nature and Environmental Technology Kanazawa UniversityKakuma-machi920-1192KanazawaJapan

This study encompassed the regular observation of nine polycyclic aromatic hydrocarbons(PAHs)and three nitro-PAHs(NPAHs)in particulate matter(PM)in Shanghai in summer and winter from 2010 to *** results showed that the mean concentrations of∑PAHs in summer decreased by 24.7%in 2013 and 18.1%in 2017 but increased by 10.2%in 2015 compared to the data in ***,the mean concentrations of∑PAHs in winter decreased by 39.7%from 2010(12.8±4.55 ng/m^3)to 2018(7.72±3.33 ng/m^3),and the mean concentrations of 1-nitropyrene in winter decreased by 79.0%from 2010(42.3±16.1 pg/m^3)to 2018(8.90±2.09 pg/m^3).Correlation analysis with meteorological conditions revealed that the PAH and NPAH concentrations were both influenced by ambient *** diagnostic ratios of PAHs and factor analysis showed that they were mainly affected by traffic emissions with some coal and/or biomass *** ratio of 2-nitrofluoranthene to 2-nitropyrene was near 10,which indicated that the OH radical-initiated reaction was the main pathway leading to their secondary ***,backward trajectories revealed different air mass routes in each sampling period,indicating a high possibility of source effects from the northern area in winter in addition to local and surrounding ***,the mean total benzo[a]pyrene-equivalent concentrations in Shanghai in winter decreased by 50.8%from 2010(1860±645 pg/m^3)to 2018(916±363 pg/m^3).These results indicated the positive effects of the various policies and regulations issued by Chinese authorities.

关键词： Air pollution Fine particulate matter Polycyclic aromatic hydrocarbons Nitropolycyclic aromatic hydrocarbons Health risk Shanghai

Identification of differentially expressed genes in esophageal cancer through SSH in combination with high throughput reverse Northern screening

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Chinese Science Bulletin 2001年第14期46卷 1195-1198页

作者： zhou Jin LIU Zhihua WANG Xiuqin DING Fang zhou Chuannong WU Min National Laboratory of Molecular Oncology Department of Cell BiologyCancer InstitutePeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100021China

To understand the molecular mechanisms of carcinogenesis of esophagus and to isolate genes with different expression levels in esophageal cancer, suppression sub-tractive hybridization (SSH) was combined with PCR-based cDNA synthesis and reverse Northern on the cancer tissues and matched almost normal mucosa using 5 microgram of total RNA as starting marterial. Eight genes were found expressed differentially in esophageal cancer, in which 5 were known genes and 3 were novel ones; and 6 were down-regulated in cancer tissues, while 2 were up-regulated; 6 were of mid-high abundance and 2 were of low abundance in esophagus. The results revealed that alteration in expression level of multiple genes underlied the initiation and development of esophageal cancer. The differentially expressed genes identified in this study such as liporcotin I, cystatin A, cystatin B, cytokeratin 13 may play roles in dedifferentiation, transformation and malignant proliferation of esophageal cancer. The combination of SSH with

关键词： esophageal cancer suppression subtractive hybridization (SSH) differential expression lipocortin cystatin.

A multifunctional osteogenic system of ultrasonically spray deposited bone-active coatings on plasma-activated magnesium

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Journal of Magnesium and Alloys 2023年第8期11卷 2719-2739页

作者： Hui Fang Shicheng zhou Xiaoyun Qi Chenxi Wang Yanhong Tian State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

Biomimetic bone-active coatings composed of inorganic nano-hydroxyapatite(i.e.,nHA)and organic silk fibroin(i.e.,SF)are layer-by-layer deposited on Mg-Zn-Ca alloy by a controllable ultrasonic spray ***,plasma activation is developed as a promising strategy to pretreat magnesium surfaces,which facilitates the direct adhesion of coatings with enhanced bonding *** this work,we engineer the nHA/SF composite coatings with excellent mechanical properties and adhesion *** optimized parameters of ultrasonic spray bring significant influence on the surface morphologies of *** by hybrid plasma of oxygen and nitrogen(i.e.,O_(2)/N_(2) plasma),the activated Mg-Zn-Ca surfaces are uniformly covered by a robust and compact nHA/SF composite coating,establishing a multifunctional system with superior corrosion resistance and biological ***,secondary oxygen plasma treatment of nHA/SF coatings(A-nHA/SF)promotes the hydrophilicity,leading to a rapid self-repair effect from surface *** improvement of anti-corrosion and self-repair provides a dependable platform for better cell adhesion,proliferation,spreading and *** favorable factors contribute to the preferable in vivo biocompatibility and the promotion of newly formed bones for the A-nHA/SF-coated Mg *** study lays important foundations for coating strategy on biomedical magnesium alloy as multifunctional osteogenic system in bioactive implantable applications.

关键词： Magnesium alloy Hydroxyapatite Silk fibroin Biocompatibility Self-repair

Whole-infrared-band camouflage with dual-band radiative heat dissipation

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Light(Science & Applications) 2023年第11期12卷 2391-2401页

作者： Bing Qin Yining Zhu Yiwei zhou Min Qiu Qiang Li State Key Laboratory of Modern Optical Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province School of EngineeringWestlake University18 Shilongshan RoadHangzhou 310024 ZhejiangChina Institute of Advanced Technology Westlake Institute for Advanced Study18 Shilongshan RoadHangzhou 310024 ZhejiangChina

Advanced multispectral detection technologies have emerged as a significant threat to objects,necessitating the use of multiband ***,achieving effective camouflage and thermal management across the entire infrared spectrum,especially the short-wave infrared(SWIR)band,remains *** paper proposes a multilayer wavelength-selective emitter that achieves effective camouflage across the entire infrared spectrum,including the near-infrared(NIR),SWIR,mid-wave infrared(MWIR),and long-wave infrared(LWIR)bands,as well as the visible(VIS)***,the emitter enables radiative heat dissipation in two non-atmospheric windows(2.5-3μm and 5-8μm).The emitter’s properties are characterized by low emittance of 0.270/0.042/0.218 in the SWIR/MWIR/LWIR bands,and low reflectance of 0.129/0.281 in the VIS/NIR ***,the high emittance of 0.742/0.473 in the two non-atmospheric windows ensures efficient radiative heat dissipation,which results in a temperature decrement of 14.4℃ compared to the Cr reference at 2000Wm^(−2) input power *** work highlights the role of solar radiance in camouflage,and provides a comprehensive guideline for developing multiband camouflage compatible with radiative heat dissipation,from the visible to LWIR.

关键词： dissipation visible radiative

Kinetics and mechanism of propylene hydro-oxidation to acrolein on Au catalysts

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Nano Research 2024年第1期17卷 354-363页

作者： Wei Du Zhihua Zhang Nan Song Xuezhi Duan Xinggui zhou State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

Propylene epoxidation by H_(2)and O_(2)to propylene oxide(PO)over the Au-Ti bifunctional catalysts,as an ideal reaction for PO production,has attracted great *** the mechanism of acrolein formation is of great importance for understanding the mechanism of molecular oxygen activation and the formation of hydroperoxo species on the Au ***,we investigate the reaction mechanism of propylene oxidation to acrolein on the Au/uncalcined TS-1(Au/TS-1-B)catalyst through a combination of multiple characterization,H_(2)/D_(2)exchange,kinetics experiment,and *** Ti sites are found to be non-essential to acrolein ***,the acrolein formation on the Au/TS-1-B catalyst is confirmed to be promoted by H_(2)through hydroperoxo species formation,which includes two main steps:propylene dehydrogenation to*C_(3)H_(5)with the aid of*OOH species,and*C_(3)H_(5)oxidation by*OOH to *** latter step is determined to be the rate-determining step because the corresponding kinetics model gives the best description for experimental *** work not only provides kinetics insights for the propylene hydro-oxidation to acrolein on the Au-Ti bifunctional catalysts,but also facilitates the rational design of Au catalysts with high activity and selectivity in the direct propylene epoxidation with H_(2)and O_(2).

关键词： kinetics mechanism gold acrolein hydro-oxidation

Analysis of the Microstructure and Mechanical Properties during Inertia Friction Welding of the Near-α TA19 Titanium Alloy

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Chinese Journal of Mechanical Engineering 2020年第6期33卷 205-217页

作者： Yanquan Wu Chunbo Zhang Jun zhou Wu Liang Yunlei Li Research and Development Center Harbin Welding Institute Limited CompanyHarbin150028China China Academy of Machinery Science and Technology Group Co. LtdBeijing100044China

The current research of titanium alloy on friction welding process in the field of aero-engines mainly focuses on the linear friction *** to the linear friction welding,inertial friction welding of titanium alloy still has important application position in the welding of aero-engine rotating ***,up to now,few reports on inertial friction welding of titanium alloy are *** this paper,the near-alpha TA19 titanium alloy welded joint was successfully obtained by inertial friction welding(IFW)*** microstructures and mechanical properties were investigated *** showed that the refined grains within 15‒20μm and weak texture were found in the weld zone due to dynamic recrystallization caused by high temperature and plastic *** weld zone consisted of acicularα′martensite phase,αp phase and metastableβ*** lath-shapedαs andβphase in base metal were transformed into acicular martensiteα′phase and metastableβphase in thermo-mechanically affected zone and heat affected *** a result,the microhardness of welded joint gradually decreased from the weld zone to the base *** specimens in room temperature and high temperature of 480℃ were all fractured in base metal illustrating that the inertia friction welded TA19 titanium alloy joint owned higher tensile strength compared to the base metal.

关键词： Inertia friction welding TA19 Micostructure Mechanical property Texture

Adopting inclined channel to decline the salinity mixing for rotary energy recovery device:Simulation and optimization

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Chinese Journal of Chemical Engineering 2021年第4期34卷 100-107页

作者： Wenjie Li Yue Wang Jie zhou Xiaoyu Qiao Shichang Xu Tianjin Key Laboratory of Membrane Science and Desalination Technology State Key Laboratory of Chemical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China

After years of research,the energy efficiency of energy recovery device has been raised to a high level,but the salinity mixing has not been effectively *** will lead to a rise of highpressure seawater salinity,which will increase the operating *** this paper,the computational fluid dynamics(CFD)simulation of the rotary energy recovery device(RERD)is carried *** is found that the unstable flow caused by the nonparallel between the channel and the flow direction of fluid is an important reason for *** the inclined channel structure is adopted,the nonparallel problem is *** formation of unstable flow is effectively *** the commercial product operating conditions,the volumetric mixing of the optimized device is reduced from 3.34%to 1.29%,showing the effectiveness of the structure.

关键词： CFD Inclined channel RERD Salinity mixing

Climatology of tropical cyclone tornadoes in China from 2006 to 2018

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Science China Earth Sciences 2020年第1期63卷 37-51页

作者： Lanqiang BAI Zhiyong MENG Kenta SUEKI Guixing CHEN Ruilin zhou School of Atmospheric Sciences and Guangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesSun Yat-sen UniversityGuangzhou 510275China Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China RIKEN Center for Computational Science Kobe 650-0047Japan

We surveyed the occurrence of tropical cyclone(TC) tornadoes in China from 2006 to 2018. There were 64 cataloged TC tornadoes, with an average of five per year. About one-third of the landfalling TCs in China were tornadic. Consistent with previous studies, TC tornadoes preferentially formed in the afternoon shortly before and within about 36 h after landfall of the TCs. These tornadoes mainly occurred in coastal areas with relatively flat terrains. The maximum number of TC tornadoes occurred in Jiangsu and Guangdong provinces. Most of the TC tornadoes were spawned within 500 km of the TC center. Two notable characteristics were found:(1) TC tornadoes in China mainly occurred in the northeast quadrant(Earth-relative coordinates) rather than the right-front quadrant(TC motion-relative coordinates) of the parent TC circulation;and(2) most tornadoes were produced by TCs with a relatively weak intensity(tropical depressions/storms), in contrast with the United States where most tornadoes are associated with stronger TCs. Further analyses showed that TC tornadoes in China tend to be spawned in an environment with large low-level storm relative helicity and large convective available potential energy taking entrainment effects into account. TC tornadoes were particularly active in 2018, with 24 reported tornadoes accounting for 37.5% of the total surveyed samples. The first recorded tornado outbreak in the modern history of China occurred in the envelope of TC Yagi(2018), in which 11 tornadoes were reported in association with significant midlevel intrusions of dry air and the interaction of Yagi with an approaching midlatitude midlevel trough.

关键词： Tornadoes Tropical cyclones Historical statistics China