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Low-Dose 1 MeV Electron Irradiation-Induced Enhancement in the Photoluminescence Emission of Ga-Rich InGaN Multiple Quantum Wells

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Chinese Physics Letters 2013年第7期30卷 135-137页

作者： zhang Xiao-fu LI yu-Dong guo Qi LU Wu Key Laboratory of functional Materials and Devices for Special Environments Xinjiang Technical Institute of Physics&ChemistryChinese Academy of SciencesUrumqi 830011

We investigate the photoluminescence(PL)emission from InGaN/GaN multiple quantum-well structures before and after 1 MeV electron *** PL peak intensity exhibits a slight enhancement after low-dose electron irradiation(2×10^(13) e/cm^(2)),and then decreases with the cumulative electron ***,the full width at half maximum of the PL spectrum narrows after low-dose electron irradiation and widens when the irradiation dose is relatively *** respect to the yellow photoluminescence,there is no significant change until the electron fluence has accumulated up to 10^(14) e/cm^(2).

关键词： InGaN/GaN Electron Quantum

Metallogenesis and ore-forming time of the Changtuxili Mn-Ag-Pb-Zn deposit in Inner Mongolia:Evidence from C-O-S isotopes and U-Pb geochronology

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Geoscience Frontiers 2020年第4期11卷 1369-1380页

作者： Kuo zhang Ruo-Shi Jin feng-yue Sun Bi-Le Li Peng He yue-Long zhang Shuo guo Tian-fu zhang College of Earth Sciences Jilin UniversityChangchun130061China Tianjin Center China Geological SurveyTianjin300170China North China Center for Geoscience Innovation Tianjin300170China Qiqihar Branch Heilongjiang Institute of Geological Survey and ResearchQiqihar150036China

This paper reports new geochronological(U-Pb) and isotope(C,O,and S) data to investigate the timing of mineralization and mode of ore genesis for the recently discovered Changtuxili Mn-Ag-Pb-Zn deposit,located on the western slopes of the southern Great Hinggan Range in NE *** mineralization is hosted by intermediate-acidic lavas and pyroclastic rocks of the Baiyingaolao *** stages of mineralization are identified:quartz-pyrite(Stage I),galena-sphalerite-tetrahedrite-rhodochrosite(Stage II),and quartz-pyrite(Stage Ⅲ).δ13C and δ18O values for carbonate from the ore vary from-8.51‰ to-4.96‰ and 3.97‰ to 15.90‰,respectively,which are indicative of a low-temperature alteration environment.δ34SV-CDT values of sulfides range from-1.77‰ to 4.16‰ and show a trend of equilibrium fractionation(δ34SPy>δ34SSp>δ34SGn).These features indicate that pyrite,sphalerite,and galena precipitated during the period of *** alteration mineral assemblage and isotope data indicate that the weakly acidic to weakly alkaline ore-forming fluid was derived largely from meteoric water and the ore-forming elements C and S originated from *** the mineralization,a geochemical barrier was formed by changes in the pH of the ore-forming fluid,leading to the precipitation of *** the basis of the mineralization characteristics,new isotope data,and comparison with adjacent deposits,we propose that the Changtuxili Mn-Ag-Pb-Zn deposit is an intermediate-to lowsulfidation epithermal deposit whose formation was controlled by fractures and variability in the pH of the oreforming *** surrounding volcanic rocks yield zircon U-Pb ages of 160-146 Ma(Late Jurassic),indicating that the mineralization is younger than 146 Ma.

关键词： Inner Mongolia Changtuxili Mn-Ag-Pb-Zn deposit C-O-S isotope geochemistry Zircon U-Pb age Intermediate-to low-sulfidation epithermal deposit

Lane Detection:A Survey with New Results

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Journal of Computer Science & Technology 2020年第3期35卷 493-505页

作者： Dun Liang yuan-Chen guo Shao-kui zhang Tai-Jiang Mu Xiaolei Huang Department of Computer Science and Technology BNRistTsinghua UniversityBeijing100084China College of Information Sciences and Technology Pennsylvania State UniversityUniversity ParkPA16802USA

Lane detection is essential for many aspects of autonomous driving,such as lane-based navigation and high-definition(HD)map *** lane detection is challenging especially with complex road conditions,considerable progress has been witnessed in this area in the past several *** this survey,we review recent visual-based lane detection datasets and *** datasets,we categorize them by annotations,provide detailed descriptions for each category,and show comparisons among *** methods,we focus on methods based on deep learning and organize them in terms of their detection ***,we introduce a new dataset with more detailed annotations for HD map modeling,a new direction for lane detection that is applicable to autonomous driving in complex road conditions,a deep neural network LineNet for lane detection,and show its application to HD map modeling.

关键词： convolutional neural network(CNN) dataset deep learning high-definition(HD)map lane detection

Ecdysone receptor isoforms play distinct roles in larval–pupal–adult transition in Leptinotarsa decemlineata

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Insect Science 2020年第3期27卷 487-499页

作者： Qing-yu Xu Pan Deng Qiong zhang Ang Li Kai-yun fu Wen-Chao guo guo-Qing Li Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests College of Plant ProtectionNanjing Agricultural UniversityNanjingChina Institute of Plant Protection Xinjiang Academy of Agricultural SciencesUrumqiChina Institute of Microbiological Application Xinjiang Academy of Agricultural ScienceUrumqiChina

A heterodimer of two nuclear receptors,ecdysone receptor(EcR)and ultraspiracle,mediates 20‐hydroxyecdysone(20E)signaling to modulate many aspects in insect life,such as molting and metamorphosis,reproduction,diapause and innate *** the present paper,we intended to determine the isoform‐specific roles of EcR during larval–pupal–adult transition in the Colorado potato ***‐stranded RNAs(dsRNAs)were prepared using the common(dsEcR)or isoform‐specific(dsEcRA,dsEcRB1)regions of EcR as *** of either dsEcR or dsEcRA,rather than dsEcRB1,by the penultimate(3rd)and final(4th)instar larvae caused failure of larval–pupal and pupal–adult *** RNA interference(RNAi)larvae remained as prepupae,or became deformed pupae and *** of messenger RNA(mRNA)levels of EcR isoforms found that LdEcRA regulates the expression of ***,silencing the two EcR transcripts,LdEcRA or LdEcRB1 reduced the mRNA levels of Ldspo and Ldsad,and lowered 20E *** contrast,the expression levels of HR3,HR4,E74 and E75 were significantly decreased in the LdEcR or LdEcRA RNAi larvae,but not in LdEcRB1 depleted *** supplement with 20E did not restore the expression of five 20E signaling genes(USP,HR3,HR4,E74 and E75),and only partially alleviated the pupation defects in dsEcR‐or dsEcRA‐fed *** data suggest that EcR plays isoform‐specific roles in the regulation of ecdysteroidogenesis and the transduction of 20E signal in ***.

关键词： ecdysone receptor Leptinotarsa decemlineata metamorphosis RNA interference

Influence of Cold-Rolling Reduction on Microstructure and Tensile Properties of Nuclear FeCrAl Alloy with Low Cr and Nb Contents

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Acta Metallurgica Sinica(English Letters) 2022年第12期35卷 2101-2110页

作者： Hui Wang Biao guo Xuguang An yu zhang Science and Technology on Reactor fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu 610213China School of Materials Science and Engineering Xihua UniversityChengdu 610039China Interdisciplinary Materials Research Center Institute for Advanced StudyChengdu UniversityChengdu 610106China

FeCrAl alloy is one of the most promising candidates as an accident-tolerant fuel(ATF)cladding ***,the influence of cold-rolling(CR)reduction on microstructure and tensile properties of the as-annealed FeCrAl alloys,with low Cr and Nb contents,is systematically *** the increase in CR reduction,the grain size of FeCrAl alloy is obviously refined after annealing because the increase in stored deformation energy leads to enhanced ***,the large CR reductions result in a severe mixed-grain microstructure,significantly reducing the uniform deformability of the FeCrAl *** dislocation density of the as-annealed FeCrAl alloy decreases with the increase in CR reduction,except for the excessive CR reduction of 50%.Moreover,the Laves phases are crushed and dissolved during CR and annealing,as well as large amounts of refined Laves phases are found after large CR *** pinning effect of the Laves phases can significantly improve the strength of FeCrAl ***,the strengthening mechanisms of FeCrAl alloy consist of fine-grain strengthening,dislocation strengthening and precipitation ***,the FeCrAl alloy,with a CR reduction of 30%,achieves optimal tensile *** study can provide theoretical guidance for the industrial production of the FeCrAl alloy.

关键词： FeCrAl alloy Cold-rolling reduction Tensile properties Microstructure evolution Strengthening mechanism

Inactive Al^(3+)-doped La(CoCrFeMnNiAl_(x))_(1/(5+x))O_(3)high-entropy perovskite oxides as high performance supercapacitor electrodes

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Journal of Advanced Ceramics 2022年第5期11卷 742-753页

作者： Meng guo yufeng LIU fengnian zhang fuhao CHENG Chufei CHENG Yang MIAO feng GAO Jun yu College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

A series of high-entropy perovskite oxides(HEPOs)La(CoCrFeMnNiAl_(x))_(1/(5+x))O_(3-δ)(x=0.4,0.5,0.6,and 0.7)have been synthesized by coprecipitation method combined with calcination process and explored as electrodes for *** crystal structure,microstructure,and elemental composition of HEPOs were investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and energy-dispersive X-ray spectroscopy(EDS)in *** electrochemical properties of HEPOs as supercapacitor electrodes were *** specific capacitances of HEPOs(x=0.4,0.5,0.6,and 0.7)are 281.84,353.65,325.60,and 259.30 F/g at the current density of 1 A/g,*** 2000 cycles,the specific capacitances of HEPOs(x=0.4,0.5,0.6,and 0.7)remain 85.01%,88.61%,86.37%,and 91.25%,*** outstanding electrochemical properties can be attributed to the entropy-stabilized structure caused by mixed six cations in B-site and the Al^(3+)-doping suppressing active ion aggregation during charge-discharge *** research highlights the potential of HEPOs as electrodes for supercapacitors.

关键词： high-entropy oxides(HEOxs) perovskite structure Al3+-doping supercapacitors

Global attractor for Hirota equation

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Applied Mathematics(A Journal of Chinese Universities) 2008年第1期23卷 57-64页

作者： zhang Rui-feng guo Bo-ling Institute of Appl. Math. College of Math. and Inform. Sci. Henan Univ. Kaifeng 475001 China. Institute of Appl. Phys. and Comput. Math. Beijing 100088 China.

The long time behavior of solution for Hirota equation with zero order dissipation is studied. The global weak attractor for this system in Hper^k is constructed. And then by exact analysis of the energy equation, it ... 详细信息

关键词： Hirota equation a priori estimate global attractor.

Evolution of Dislocation Loops in AL-6XN Stainless Steels Irradiated by Hydrogen Ions

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Acta Metallurgica Sinica(English Letters) 2017年第1期30卷 89-96页

作者： Zhong-Cheng Zheng Yan-Xia yu Wei-Ping zhang Zhen-yu Shen feng-feng LUO Li-Ping guo Yao-Yao Ren Rui Tang Hubei Nuclear Solid Physics Key Laboratory Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology Wuhan University Wuhan 430072 China Institute of Applied Physics Jiangxi Academy of Science -Nanchang 330029 China Center for Electron Microscopy Wuhan University Wuhan 430072 China Science and Technology on Reactor fuel and Materials Laboratory Nuclear Power Institute of China Chengdu 610041 China

AL-6XN stainless steels, one of the candidate structure materials for supercritical water-cooled reactor, were irradiated from 0.5 to 5 dpa using 100 keV H2＋ ions at 290 and 380 ℃. Microstructures were characterized by transmission electron microscopy （TEM）. Dislocation loops were the dominant radiation-induced defects. All the dislocation loops had 1/3 〈111〉 type Burgers vector. Number density and size of the loops have been measured. Nucleation and evolution of dislocation loops were also investigated. Voids were observed only in the condition of 5 dpa at 380 ℃. Different evolution mechanisms of the radiation-induced dislocation loops were discussed. Effects of hydrogen and elevated temperature on the microstructural evolution were also investigated. Besides, the formed voids have a further effect on the evolution of dislocation loops.

关键词： Supercritical water-cooled reactor Austenitic stainless steels Ion irradiation Dislocation loops Hydrogen

Effect of Martensite Morphology on Impact Toughness of Ultra-High Strength 25CrMo48V Steel Seamless Tube Quenched at Different Temperatures

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Journal of Iron and Steel Research International 2013年第2期20卷 62-67页

作者： zhang Chuan-you WANG Qing-feng KONG Jin-li XIE guo-zhu WANG Ming-zhi zhang fu-cheng State Key Laboratory of Metastable Materials Science and Technology Yanshan University National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan University

A 25CrMo48V steel for ultra-deep oil/gas well casings was quenched at 900-1 200 ℃ and tempered at 650 ℃. The lath martensitic structures were characterized by optical microscope （OM）, field emission scanning electron microscopy （FESEM）, electron backscattering diffraction （EBSD） and transmission electron microscopy （TEM）, and the transverse impact energy at 0 ℃ was measured from the as-quenched and tempered specimens. The results show that with the quenching temperature decreased, the prior austenite grain, martensitic packet and block are refined, while the lath width seems to remain unchanged. The enhancement of impact toughness with the decreasing quenching temperature can be attributed to refinement of the martensitic structure with high-angle boundaries, and the block is the minimum structure unit controlling impact toughness. The transverse impact energy [ECVN （0 ℃） ≥100 J] required for seamless casings with ultra-high strength （Rp0.2≥932 MPa） has been finally achieved with the experimental steel quenched at 900-1 000 ℃ and tempered at 650 ℃.

关键词： seamless steel tube lath martensitic morphology toughness