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Deposition of Phase-pure Cr2AlC Coating by DC Magnetron sputtering and Post Annealing Using Cr-Al-C Targets with Controlled Elemental Composition but Different Phase Compositions

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Journal of Materials science & Technology 2018年第3期34卷 466-471页

作者： yueming li Guorui Zhao yuhai Qian Jingjun xu Meishuan li shenyang National Laboratory for Materials science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China University of Chinese Academy of sciences Beijing 100039China

Polycrystalline Cr2AlC coatings were prepared on M38G superalloy using a two-step method consisting of magnetron sputtering from Cr-Al-C composite targets at room temperature and subsequent annealing at 620 ℃. Particularly, various targets synthesized by hot pressing mixture of Cr, Al, and C powders at 650-1000 ℃ were used. It was found that regardless of the phase compositions and density of the com- posite targets, when the molar ratio of Cr：Al：C in the starting materials was 2：1：1, phase-pure crystalline Cr2AlC coatings were prepared by magnetron sputtering and post crystallization. The Cr2AIC coatings were dense and crack-free and had a duplex structure. The adhesion strength of the coating deposited on M38G superalloy from the 800 ℃ hot-pressed target and then annealed at 620 ℃ for 20 h in Ar exceeded 82 ± 6 MPa, while its hardness was 12 ± 3 GPa.

关键词： Cr2AlC Coating Magnetron sputtering Composite target Heat treatment

Influence of Vehicle Parameters on Critical Hunting speed Based on Ruzicka Model

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Chinese Journal of Mechanical Engineering 2012年第3期25卷 536-542页

作者： CUI Dabin li li JIN Xuesong XIAO Xinbiao DING Junjun school of Mechanical Engineering Southwest Jiaotong University Chengdu 610031 China state Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China

While introducing foreign advanced technology and cooperating with Chinese famous research institutes,the high-speed vehicles are designed and take the major task of passenger transport in *** high-speed vehicle,the characteristic of shock absorber is an important parameter which determines overall behavior of the *** most existing researches neglect the influence of the series stiffness of the shock absorber on the vehicle dynamic behavior and have one-sided views on the equivalent conicity of wheel *** this paper,a high speed passenger vehicle in China is modeled to investigate the effect of the parameters taking series hydraulic shock absorber stiffness into consideration on Ruzicka *** the vehicle dynamic model,the effect of main suspension parameters on critical speed is *** order to verify the reasonableness of shock absorber parameter settings,vibration isolation characteristics are calculated and the relationship between suspension parameters and the vehicle critical hunting speed is *** study the influence of equivalent conicity on vehicle dynamic behavior,a series of wheel treads with different conicities are set and the vehicle critical hunting speeds with different wheel treads are *** discipline between the equivalent conicity of wheel tread and critical speed are obtained in vehicle nonlinear *** research results show that the critical speed of vehicle much depends on wheelset positioning stiffness and anti-hunting motion damper,and the series stiffness produces notable effect on the vehicle dynamic *** critical speed has a peak value with the equivalent conicity increasing,which is different from the traditional opinion in which the critical speed will decrease with the conicity *** relationship between critical speed and conicity of wheel tread is effected by the suspension parameters of the *** study results obtained offer a method and useful data to designing the

关键词： high-speed vehicle critical hunting speed suspension system equivalent conicity

Towards the Unified Principles for Level 5 Autonomous Vehicles

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Engineering 2021年第9期7卷 1313-1325页

作者： Jianqiang Wang Heye Huang Keqiang li Jun li state Key Laboratory of Automotive safety and Energy School of Vehicle and MobilityTsinghua UniversityBeijing 100084China

The rapid advance of autonomous vehicles(AVs)has motivated new perspectives and potential challenges for existing modes of ***,driving assistance systems of Level 3 and below have been widely produced,and several applications of Level 4 systems to specific situations have also been gradually *** improving the automation level and vehicle intelligence,these systems can be further advanced towards fully autonomous ***,general development concepts for Level 5 AVs remain unclear,and the existing methods employed in the development processes of Levels 0-4 have been mainly based on task-driven function development related to specific ***,it is difficult to identify the problems encountered by high-level *** essential logical and physical mechanisms of vehicles have hindered further progression towards Level 5 *** exploring the physical mechanisms behind high-level autonomous driving systems and analyzing the essence of driving,we put forward a coordinated and balanced framework based on the brain-cerebellum-organ concept through reasoning and *** on a mixed mode relying on the crow inference and parrot imitation approach,we explore the research paradigm of autonomous learning and prior knowledge to realize the characteristics of self-learning,self-adaptation,and self-transcendence for *** a systematic,unified,and balanced point of view and based on least action principles and unified safety field concepts,we aim to provide a novel research concept and develop an effective approach for the research and development of high-level AVs,specifically at Level 5.

关键词： Autonomous vehicle Principle of least action Driving safety field Autonomous learning Basic paradigm

Facile synthesis and electrochemical properties of MnO_2/carbon nanotubes

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Particuology 2014年第4期12卷 34-38页

作者： yang Lv Huanqiao li yan Xie shushuang li Jia li yongheng Xing yujiang song College of Chemistry and Chemical Engineering Liaoning Normal University Dalian National Laboratories for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of Sciences Dalian University of Technology

The poor electrical conductivity of MnO2 limits its use as an electrode material. To overcome this limitation, we report an easy and rapid approach to deposit nanosized MnO2 onto multi-wall carbon nanotubes functionalized with hydroxyl groups （MWCNTs-OH） by chemical reduction of KMnO4 with MnsO4 in aqueous solution under ambient conditions. Characterization with XRD and TEM reveals that the obtained MnO2/MWCNTs-OH composite is nanocrystalline and partially covered by Mn02 nanosheets with a thick- ness of 1-3 nm at a MnO2 loading of 20 wt%. Cyclic voltammetry （CV） and galvanostatic charge-discharge measurements reveal that the MnO2/MWCNTs-OH composite with a MnO2 loading of 20 wt% has a relatively high specific capacitance of 234 F/g at a scan rate of 2 mV/s and exhibits good cycling stability. Furthermore, the oxygen reduction reaction （ORR） shows that MnO2/MWCNTs-OH composite may have potential applications as a non-noble metal electrocatalyst in fuel cells and metal-air batteries.

关键词： MnO2 MWCNTs-OH supercapacitorNon-noble metal electrocatalyst

Growth rate,catalase and superoxide dismutase activities in rock carp(Procypris rabaudi Tchang) exposed to supersaturated total dissolved gas

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Journal of Zhejiang University-science B(Biomedicine & Biotechnology) 2011年第11期12卷 909-914页

作者： Xiao-qing liU Ke-feng li Jun DU Jia li Ran li state Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China Fisheries Institute Sichuan Academy of Agricultural Sciences Chengdu 611731 China

Total dissolved gas supersaturation(TDGs) appears when the pressures of gases in a solution exceed the barometric *** is often caused by flood discharge at *** may lead to gas bubble disease(GBD) for fish and biochemical responses of selected fish and other aquatic *** purpose of this study was to determine the impact of long-term TDGs levels on the growth and biochemical responses of rock carp(Procypris rabaudi Tchang) dwelling in the upper reaches of the yangtze ***-year-old rock carp were exposed to TDGs levels at 100%,104%,108%,112%,and 116% for 42 *** were taken every 7 d after the start of the trial in order to determine catalase(CAT) and superoxide dismutase(sOD) activities in gill and muscle *** were taken at Days 0 and 42 of exposure to determine growth *** effect was found on growth rate in all treatment *** and CAT activities varied in different tissues,according to time of exposure and TDGs *** biochemical response of fish exposed to TDGs was more obvious in gill tissue than in muscle *** of sOD and CAT activities in different tissues offer important information about the effect of TDGs on the rare fish in the yangtze River,and may help evaluate the risk to the aquatic eco-environment and aquatic ecosystem in the downstream of the yangtze River.

关键词： Total dissolved gas supersaturation (TDGs) Rock carp (Procypris rabaudi Tchang) Growth rate Catalase superoxide dismutase

Recognition of abnormal body surface characteristics of oplegnathus punctatus

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Information Processing in Agriculture 2022年第4期9卷 575-585页

作者： Beibei li Jun yue shixiang Jia Qing Wang Zhenbo li Zhenzhong li school of Information and Electrical Engineering Ludong UniversityYantai 264025China school of Civil Engineering Ludong UniversityYantai 264025China school of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China shandong Dongrun Instrument Technology Co. Ltd.264000China

To identify the abnormal characteristics of the oplegnathus punctatus is great importance to the detection of iridovirus disease in the breeding *** this paper,an advanced neural network model to identify the characteristics of the oplegnathus puncta-tus and predict its different periods of suffering from iridovirus disease is proposed based on the establishment of a data *** of all,a standard format data set of oplegnathus punctatus and an abnormal format date set are established in order to verify the effective-ness of the method in this *** then,the feature extraction fusion method is used for preprocessing in terms of the abnormal format data set,which combines the edge fea-tures extracted by the improved multi-template sobel operator and the color features extracted by the HsV ***,an improved VGG-GoogleNet network recognition model comes into being through the fusion and improvement of the VGG and GoogleNet neural network *** experiments results show that the prediction accuracy rate for oplegnathus punctatus suffering from iridovirus disease in the the abnormal format data set and the standard format data set are improved,which reach 98.55%and 69.18%.

关键词： Oplegnathus punctatus Body surface characteristics Red seabream iridovirus Abnormal recognition Transfer learning

Influencing Factors and Improvement suggestions for Agricultural Green Development Performance:Empirical Insights from China

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Chinese Geographical science 2023年第5期33卷 917-933页

作者： li Erling ZHANG Mengzhen li Ruolan DENG Qingqing Key Research Institute of yellow River Civilization and sustainable Development&Collaborative Innovation Center on yellow River Civilization of Henan Province Henan UniversityKaifeng 475001China Key Laboratory of Geospatial Technology for the Middle and Lower yellow River Regions/The College of Geography and Environmental science Henan UniversityKaifeng 475001China Institute of sustainable Development in Agriculture and Rural Area Henan UniversityKaifeng 475004China

Agricultural green development is an essential direction for global sustainable *** academic literature,however,needs to place greater emphasis on studying the factors influencing agricultural green development performance and how such performance can be improved.A theoretical framework for agricultural green development performance was constructed in this paper using the super-sBM model,which considers undesirable outputs,to measure the agricultural green development performance of 330 cities at or above the prefecture level in China(excluding Tibet Autonomous Region,Hong Kong,Macao and Taiwan of China)from 2007 ***,the influencing mechanism of agricultural green development performance was then analyzed using a spatial econometric *** results show that:1)from 2007 to 2018,China’s agricultural green development performance experienced three stages of evolution:‘rise,decline and rise’.2)The regions with high performance agricultural green development are mainly distributed in eastern China,northeastern China,and southern Qinghai Province.3)The agricultural economic level,industrialization process,and labor quality play significant roles in promoting local agricultural green development performance,while such performance is obviously inhibited by the openness level and the government’s environmental *** agricultural green development performance is significant inhibited by the agricultural economic level and accelerated industrialization process in neighboring cities,while significantly promoted by the agricultural industrial structure in neighboring *** suggestions for improving agricultural green development performance are proposed based on these research results,which can provide scientific references for promoting sustainable agriculture.

关键词： agricultural green development performance influencing factors improvement suggestions China

Effect of M-A constituents formed in thermo-mechanical controlled process on toughness of 20CrNi2MoV steel

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Journal of Iron and steel Research International 2019年第12期26卷 1340-1349页

作者： Bin-zhou li Chang-sheng li Xin Jin Jian Zhang state Key Laboratory of Rolling Technology and Automation Northeastern UniversityShenyang 110819LiaoningChina Ansteel Beijing Research Institute Beijing 102211China

The effect of martensite–austenite(M–A)constituents formed in thermo-mechanical controlled process on impact toughness of 20CrNi2MoV steel was *** variation in fraction,size and morphology of M–A constituent and its effect on toughness under different cooling rates were carried *** result shows that there was no significant change in the fraction of M–A constituent under different cooling rates,but the distribution and size of M–A constituent were greatly influenced by cooling rate,which consequently influenced *** amount of large blocky M–A constituents decreased from 4.7%to 1.7%,while that of elongated M–A constituents increased from 3.8%to 8.6%with the cooling rate increasing from 7 to 26°C/s,and the corresponding impact energy decreased from 132 to 84 *** deterioration of impact toughness could be related to the increase in the elongated M–A *** elongated M–A constituents existing along the prior austenite grain boundaries in samples of 26°C/s could easily lead to the formation of cleavage crack,which then results in the lower crack initiation energy than that of low cooling rate samples.

关键词： 20CrNi2MoV steel Martensite–austenite constituent Thermo-mechanical controlled process Continuous cooling process Impact toughness

NGs-metabarcoding revealing novel foraminiferal diversity in the Western Pacific Magellan seamount sediments

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Journal of Oceanology and limnology 2021年第5期39卷 1718-1729页

作者： Junfeng sHI yanli LEI Haotian li Tiegang li Laboratory of Marine Organism Taxonomy and Phylogeny Institute of OceanologyChinese Academy of SciencesQingdao 266071China Key Laboratory of Marine sedimentology and Environmental Geology First Institute of OceanographyMinistry of Natural Resources(MNR)Qingdao 266061China Clinical Research Center Affi liated Hospital of Weifang Medical UniversityWeifang 261031China southern Marine science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of sciences Beijing 100049China Center for Ocean Mega-science Chinese Academy of SciencesQingdao 266071China

seamount is a unique deep-sea ecosystem widely distributed in the *** biodiversity is vibrant due to its specific geographical and hydrological ***,the diversity and features of foraminifera in such an environment have rarely been *** extracted environmental DNA(eDNA)in sedime nts and amplified the partial small subunit ribo somal DNA(ssU rDNA)of fo raminife ra to understand the foraminiferal diversity from four sites in Magellan seamount(Western Pacific Ocean).Partial s sU rDNA sequencing was conducted and 912979 foraminiferal reads were obtained and gathered into 266 operational taxonomic units(OTUs).In the available dataset,a high proportion of rare OTUs and low identity OTUs in each studied sample showed that the Magellan seamount foraminiferal community might have a high genetic *** relative abundance of foraminifera varied between replicates probably due to the existence of bias in amplification process and patchiness of the deep-sea *** showed that the Magellan seamount has a relatively high benthic foraminiferal diversity characterized mainly by monothalamiids(76.37%of total reads)in association with rotaliids(19.03%of total reads),including planktic foraminiferal sequences(38.58%of rotaliids;7.36%of total reads).The remaining reads were assigned to miliolids(0.83%of total reads)and textulariids(0.66%of total reads),and 3.11%of total reads are unassigned to a specific *** co mparative analysis with foraminiferal assemblage s from coastal and deep-sea environme nts indicated that seamounts could aggregate species from a nearby deep-sea.

关键词： metabarcoding Magellan seamount foraminifera Western Pacific Ocean