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Defence Technology（防务技术） 2022年第5期18卷 723-734页

作者： qing-bo yu Jia-hao Zhang hong-wei Zhao Yan-wen Xiao Hai-fu Wang beijing Institute of Technology State Key Laboratory of Explosion Science and TechnologyBeijing100081China Academy of the Rocket Force Beijing100094China Equipment Project Management Center Army Equipment DepartmentBeijing100072China

Ballistic impact and sealed chamber tests were performed on the steel-encased reactive material projectile(SERMP)to understand its behind-plate overpressure effect when impacting the thin aluminum *** reactive material encased with a 1.5 mm thick 30CrMnSiNi2A steel shell was launched onto the initially sealed test chamber with a 3 mm thick 2024-T3 thin aluminum cover ***,the overpressure signals in the test chamber were recorded by pressure *** experimental results indicate an unusual behind-plate overpressure effect:as the density of the projectile increases from 6.43 g/cm^(3) to 7.58 g/cm^(3) by increasing the content of tungsten powder,although its total chemical energy decreases,it produces a higher behind-target overpressure at a lower impact velocity.A theoretical model is proposed to predict the reaction length of reactive material inside the projectile based on one-dimensional shock wave theory to understand this unexpected *** addition,the deviation between the actual energy release and the theoretical calculation results,also the variation of overpressure rise time are analyzed and *** the analyses show,when the SERMP successfully penetrates the cover plate,an increasing density of the reactive material inside the projectile always means that the delaying rarefaction wave effect,an increase of its internal pressure and strain rate *** factors lead to the increase of the overpressure limit velocity and reaction extent of the reactive material,while the overpressure rise time decreases.

关键词： Reactive materials Steel-encased reactive material projectile Over-pressure effect Overpressure limit velocity Energy release

Recovery of iron from copper slag by deep reduction and magnetic beneficiation

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International Journal of Minerals,Metallurgy and Materials 2013年第11期20卷 1035-1041页

作者： Ke-qing Li Shuo Ping hong-yu Wang wen Ni Key Laboratory of the Ministry of Education of China for High-Efcient Mining and Safety of Metal Mines University of Science and Technology Beijing School of Civil and Environmental Engineering University of Science and Technology Beijing

Aiming at recovering iron from high-iron-content copper slag, this article introduced a combination technol- ogy of deep reduction and magnetic beneficiation, investigated the iron recovery efficiency and optimized the technical conditions. When coke powder with 86wt% fixed carbon was used as a reductant, iron was successfully extracted from the copper slag. Under the optimized condition of the coke powder content of 14wt%, the calcium-to-silicon mass ratio （Ca/Si） of 0.2, the roasting temperature of 1300℃, the roasting time of 3 h, the grinding time of 20 min, and the magnetic field intensity of 61 kA-m-1, the iron recovery rate of the copper slag can reach 91.82%, and the extracted iron powder has an iron grade of 96.21%. With the characteristics of high iron grade and low impurity content, the extracted iron powder can be used as high-quality raw materials of weathering steel.

关键词： copper slag waste utilization ore reduction magnetic separation beneficiation

Improving interfacial and electrical properties of HfO_(2)/SiO_(2)/p-Si stacks with N_(2)-plasma-treated SiO_(2) interfacial layer

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Rare Metals 2023年第6期42卷 2081-2086页

作者： Xiao-Qiang Chen yu-hua Xiong Jun Du Feng Wei hong-Bin Zhao qing-Zhu Zhang wen-Qiang Zhang Xiao-Ping Liang Advanced Electronic Materials Institute General Research Institute for Nonferrous MetalsBeijing100088China State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous MetalsBeijing100088China Key Laboratory of Microelectronics Devices and Integrated Technology Institute of MicroelectronicsChinese Academy of SciencesBeijing100029China

The effect of N_(2)-plasma-treated SiO_(2) interfacial layer on the interfacial and electrical characteristics of HfO_(2)/SiO_(2)/p-Si stacks grown by atomic layer deposition(alD) was *** microstructure and interfacial chemical bonding configuration of the HfO_(2)/SiO_(2)/Si stacks were also examined by high-resolution transmission electron microscopy(HRTEM) and X-ray photoelectron spectroscopy(XPS).Compared with the samples without N2-plasma treatment,it is found that the samples with N2-plasma treatment have less oxygen vacancy density for SiO_(2) interfacial layer and better HfO_(2)/SiO_(2) *** agreement with XPS analyses,electrical measurements of the samples with N2-plasma treatment show better interfacial quality,including lower interface-state density(Dit,9.3 × 1011 cm^(-2)·eV^(-1) near midgap) and lower oxidecharge density(Q_(ox),2.5 × 1012 cm^(-2)),than those of the samples without N_(2)-plasma ***,the samples with N_(2)-plasma treatment have better electrical performances,including higher saturation capacitance density(1.49 μF·cm^(-2)) and lower leakage current density(3.2 × 10^(-6) A·cm^(-2) at V_(g)=V_(fb)-1 V).furthermore,constant voltage stress was applied on the gate electrode to investigate the reliability of these *** shows that the samples with N_(2)-plasma treatment have better electrical stability than the samples without N_(2)-plasma treatment.

关键词： Metal-oxide-semiconductor High-k Atomic layer deposited N_(2)-plasma treatment Interfacial characteristic Reliability

The precipitation strengthening behavior of Cu-rich phase in Nb contained advanced Fe-Cr-Ni type austenitic heat resistant steel for USC power plant application

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Progress in Natural Science:Materials International 2012年第3期22卷 175-185页

作者： Cheng-yu Chi a, hong-yao yu b, Jian-xin Dong b, wen-qing Liu c, Shi-chang Cheng d, Zheng-dong Liu d, Xi-shan Xie b a School of Metallurgical and Ecological Engineering, University of Science & Technology beijing, beijing 100083, China b School of Materials Science and Engineering, University of Science & Technology beijing, beijing 100083, China c Instrumental Analysis & Research Center, Shanghai University, Shanghai 200444, China d Central Iron and Steel Research Institute, beijing 100081, China [a] School of Metallurgical and Ecological Engineering University of Science & Technology Beijing Beijing 100083 China [b] School of Materials Science and Engineering University of Science & Technology Beijing Beijing 100083 China [c] Instrumental Analysis & Research Center Shanghai University Shanghai 200444 China [d] Central Iron and Steel Research Institute Beijing 100081 China

Copper has been used as a strengthening element in newly developed Fe-Cr-Ni type austenitic heat resistant steel for inducing Cu-rich phase precipitation to meet high temperature strength requirement for 600 ℃ Ultra Super-Critical (USC) coal fired power plants for many years. However, the precipitation behavior and strengthening mechanism of Cu-rich phase in these advanced austenitic heat resistant steels is still unclear. In order to understand the precipitation strengthening behavior of Cu-rich phase and to promote high strength austenitic heat resistant steel development, 18 Cr9 NiCuNb steel which is a Cu-added Nb contained advanced Fe-Cr-Ni type austenitic heat resistant steel has been selected for this study to be aged at 650 ℃ till to 10,000 h. Micro-hardness and room temperature tensile test were conducted after long-time aging. SEM, TEM, HRTEM and three dimensional atom probe (3DAP) technology accompanying with thermodynamic calculation have been used to investigate the Cu-rich phase precipitation behavior during 650 ℃ aging. The experimental results showed that Cu atoms can quickly concentrate in clusters at very early precipitation stage to form the fine nano-size Cu-rich "segregation areas" within less than 1 h at 650 ℃. With increasing aging time at 650 ℃ Cu atoms continuously concentrate to Cu-rich segregation areas (clusters) and simultaneously other kinds of atoms such as Fe, Cr and Ni diffuse away from Cu-rich segregation areas to austenitic matrix, and finally to complete the transformation from Cu-rich segregation areas to Cu-rich phase. However, there is only Cu atoms concentration but not crystallographic transformation from early stage of Cu-rich clusters forming to the final Cu-rich phase formation. Even the Cu atom becomes the main composed element after 500 h aging at 650 ℃ the Cu-rich phase still keeps coherent relationship with austenitic matrix. According the experimental results in this study, Cu-rich phase precipitation sequence which st

关键词： USC power plant Austenitic heat resistant steel Microstructure Cu-rich phase TEM 3DAP

Free-standing two-dimensional Au films

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Rare Metals 2022年第12期41卷 4235-4240页

作者： Shi-Zhuang Gao Mu Yang qing-yun Xiang yu Wang huan Zhang Yang Bai wen-qing Yao Jiang-Li cao Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Corrosion-Erosion and Surface Technology beijing Key Laboratory Beijing 100083China Department of Applied Physics Hong Kong Polytechnic UniversityHong KongChina Department of Chemistry Tsinghua UniversityBejing 100084China

Free-standing two-dimensional(FS-2D) materials of covalent or ionic bonds can be prepared through mechanical exfoliation by virtue of their intrinsic layered crystal ***,following this strategy,it was reported the fabrication of large-area FS-2D Au films with controllable lattice orientations via an electrochemical hydrogen-detaching *** was further characterized the catalytic properties of FS-2D ***(111)-oriented FS-2D Au with 20 nm in thickness shows a catalytic conversion up to 43.8% for the oxidation of cyclohexane as a model reaction system,a result of more than double of generally reported *** exceptionally high catalytic activity could be attributed to the flexible structure of the FS-2D Au catalyst,which differs from the rigid structure of general *** results give useful implications for large-scale productions of a variety of FS-2D metals with controllable orientations,by which their applications may not be confined to catalysis chemistry.

关键词： Free-standing two-dimensional Au thin films Eelectrochemical hydrogen-detaching method Catalysis

Major physiological adjustments in freezing-tolerant grey tiger longicorn beetle(Xylotrechus rusticus) during overwintering period

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Journal of Forestry Research 2014年第3期25卷 653-659页

作者： Jue-wen Li Juan Shi yu Xue hong-bo Mao You-qing Luo beijing Key Laboratory of Forest Pest Control Beijing Forestry University College of Forestry Northeast Forestry University Forestry Administration of Acheng District

1Xylotrechus rusticus （Linnaeus） is one of the most destruc-tive woodborers in northeast China;it damages poplar and is listed as a domestic forestry quarantine pest. Overwintering larvae were collected during October 2012 and March 2013 in Harbin, China, to quantify indi-cators related to the insect’s overwintering strategy and the major cryo-protectants. The supercooling points （SCPs）, which ranged from-14.7＆#176;C to -2.9＆#176;C, were higher than the lethal temperatures of LT50 （-33.64＆#176;C） and LT99 （-40.17＆#176;C） after 24 h exposure. , also the minimum mean daily temperature （-24.5＆#176;C） and mean monthly temperature （-18.0＆#176;C） at the sampling site in January during 2008-2012. Thus, X. rusticus is a typical freezing-tolerant insect. Glycerol serves as a major cryoprotectant for overwintering larvae , because it was the only polyol accumulated during the winter and it also had a significant negative correlation with the SCP （p=0.033, R=0.907）. The glycogen and lipid are major sources of ener-gy and their levels decreased substantially in the middle of overwintering, when glycogen had a significant correlation with the SCP （p= 0.006, R=0.971） whereas the lipid contents did not. Moreover, inter-conversions between glycerol and glycogen, as well as mannose and glycogen, were suggested by their negative correlations. The water content did not change obviously during the winter and was not correlated with the SCP. The free amino acids in the hemolymph and the total protein contents of the bodies of larvae changed significantly during winter, although both had no correlations with the SCP.

关键词： cold hardiness cryoprotectant freezing tolerant physiological variation Xylotrechus rusticus.

Trends in Lipids Level and Dyslipidemia among Chinese Adults, 2002-2015

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Biomedical and Environmental Sciences 2019年第8期32卷 559-570页

作者： SONG Peng Kun MAN qing qing LI hong PANG Shao Jie JIA Shan Shan LI yu Qian HE Li ZHAO wen hua ZHANG Jian National Institute for Nutrition and Health Chinese Center for Disease Control and PreventionBeijing 100050China Central laboratory of beijing Center for Disease Control and Prevention Beijing 100013China Academy of National Food and Strategic Reserves Administration Beijing 100037China

Objective To investigate the trends of lipid profiles and dyslipidemia among Chinese adults from 2002 to *** Data were collected from three nationally representative cross-sectional *** venous blood samples were collected and serum lipids were tested by biochemical analysis and enzymatic *** levels and the prevalence of dyslipidemia among adults were analyzed with complex sampling weighting adjustment for age and *** The weighted means of TC, TG, and LDL-c significantly increased linearly from 3.93, 1.12, and 2.12 mmol/L in 2002 to 4.59, 1.41, and 2.78 mmol/L in 2010 and then to 4.63, 1.47, and 2.87 mmol/L in 2015, respectively;by contrast, HDL-c levels decreased significantly from 1.30 mmol/L to 1.26 mmol/L over the same *** trends in mean non-HDL-c and lipid-related ratios were *** weighted dyslipidemia prevalence linearly increased;in particular, hypercholesterolemia increased from 1.6% to 5.6% and then to 5.8%, hypertriglyceridemia increased from 5.7% to 13.6% and then to 15.0%, low HDL-c increased from 18.8% to 35.5% and then to 24.9%, and high LDL-c increased from 1.3% to 5.6% and then to 7.2%(P for trend <0.001).Conclusion Dyslipidemia increased among Chinese adults from 2002 to *** of a comprehensive strategy to decrease lipid levels in this population is urgently required.

关键词： Lipids Dyslipidemia Cross-sectional study Adults China

Commissioning of laser electron gamma beamline SLEGS at SSRF

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Nuclear Science and Techniques 2022年第7期33卷 103-114页

作者： hong-Wei Wang Gong-Tao Fan Long-Xiang Liu Hang-hua Xu wen-qing Shen yu-Gang Ma Hiroaki Utsunomiya Long-Long Song Xi-Guang cao Zi-Rui Hao Kai-Jie Chen sheng Jin yu-Xuan Yang Xin-Rong Hu Xin-Xiang Li Pan Kuang Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai201800China University of Chinese Academy of Science Beijing100049China fudan University Shanghai200433China Department of Physics Konan UniversityKobe658-8501Japan ShanghaiTech University Shanghai201210China Zhengzhou University Zhengzhou450001China

The Shanghai Laser Electron Gamma Source(SLEGS)is a powerful gamma source that provides MeV gamma-ray beams for nuclear science and *** was developed as one of the 16 beamline stations in the Phase Ⅱ Project of the Shanghai Synchrotron Radiation *** slant-scattering mode is for the first time systematically employed in laser Compton scattering at SLEGS to produce energy-tunable quasi-monoenergetic gamma-ray *** SLEGS officially completed its commissioning from July to December *** rays in the energy range of 0.25-21.7 MeV with a flux of 2.1×10^(4)-1.2×10^(7) photons/s and an energy spread of 2-15% were produced during the *** paper reports the results from commissioning the SLEGS beamline.

关键词： SLEGS Laser Compton scattering Slant-scattering mode Backscattering mode

Independent prognostic value of the congestion and renal index in patients with acute heart failure

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Journal of Geriatric Cardiology 2023年第7期20卷 516-526页

作者： Run-qing JI Bin WANG Jin-Guo ZHANG Shu-hong SU Li LI Qin yu Xian-YanJIANG Xin fu Xue-hua FANG Xiao-wen MA Ao-Xi TIAN Jing LI National Clinical Research Center for Cardiovascular Diseases NHC Key Laboratory of Clinical Research for Cardiovascular MedicationsState Key Laboratory of Cardiovascular DiseaseFuwai HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeNational Center for Cardiovascular DiseasesBeijingChina fuwai hospital Chinese Academy of Medical SciencesShenzhenChina Department of Cardiology Affiliated Hospital of Jining Medical UniversityJiningChina Department of Cardiology Xinxiang Central HospitalXinxiangChina Department of Cardiology Shanxi Fenyang HospitalFenyangChina Department of Cardiology Affiliated Zhongshan Hospital of Dalian UniversityDalianChina Heart Center Qingdao Fuwai Cardiovascular HospitalQingdaoChina Department of Cardiology the First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina Department of Cardiology Beijing Liangxiang HospitalBeijingChina Department of Cardiology Qinyang People’s HospitalQinyangChina

BACKGROUND Clinical outcomes are poor if patients with acute heart failure(AHF)are discharged with residual congestion in the presence of renal ***,there is no single indication to reflect the combined effects of the two related pathophysiological ***,therefore,proposed an indicator,congestion and renal index(CRI),and examined the associations between the CRI and one-year outcomes and the incremental prognostic value of CRI compared with the established scoring systems in a multicenter prospective cohort of *** We enrolled AHF patients and calculated the ratio of thoracic fluid content index divided by estimated glomerular filtration rate before discharge,as *** we examined the associations between CRI and one-year *** A total of 944 patients were included in the analysis(mean age 63.3±13.8 years,39.3%women).Compared with patients with CRI≤0.59 mL/min per kΩ,those with CRI>0.59 mL/min per kΩhad higher risks of cardiovascular death or HF hospitalization(HR=1.56[1.13-2.15])and all-cause death or all-cause hospitalization(HR=1.33[1.01-1.74]).CRI had an incremental prognostic value compared with the established scoring *** In patients with AHF,CRI is independently associated with the risk of death or hospitalization within one year,and improves the risk stratification of the established risk models.

关键词： patients acute index