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African swine fever and meat prices fluctuation:An empirical study in China based on TVP-VAR model

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Journal of Integrative Agriculture 2021年第8期20卷 2289-2301页

作者： LI Hui-shang HU chen-pei LÜZheng LI Mei-qi GUO Xin-zhu Agricultural Information Institute/Key Laboratory of Big Agri-Data of Ministry of Agriculture and Rural Affairs Chinese Academy of Agricultural SciencesBeijing 100081P.R.China International Statistical Information Center National Bureau of StatisticsBeijing 100826P.R.China School of Statistics and Mathematics Central University of Finance and EconomicsBeijing 100081P.R.China

African swine fever(ASF),a fatal disease outbroken in China in August 2018,has widely attracted social concern especially in the information *** occurrence of ASF led to an imbalance between supply and demand in pork and other meat *** a result,meat prices fluctuated greatly during the past year in *** measure ASF quantitatively,the internet public concern index about ASF was created using web crawler *** relationships between ASF and meat prices were analyzed based on time-varying parameter vector auto-regressive(TVP-VAR)*** results showed that there were some differences in the impact size,direction and duration of ASF on the prices of pork,chicken,beef and mutton,and the characteristics of time variability and heterogeneity were *** the same time,the impact of ASF on meat prices is not consistent with the trend and degree of *** impulse intensity is strongly correlated with the strength and duration of ASF,and it is generally weak in the early stage and much stronger in the middle and late *** results indicate that macro regulations,monitoring and early-warning system,standardizing production and circulation,and the public opinion monitoring and guidance about ASF should be given more attention in future to stabilize the market expectations and to promote a smooth functioning of the livestock markets.

关键词： African swine fever meat prices dynamic transmission TVP-VAR model

The Late Quaternary Coastal Geo-Environment Evolution and Modern Process of Bohai Bay,China

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Acta Geologica Sinica(English Edition) 2015年第6期89卷 2101-2102页

作者： WANG Fu shang Zhiwen LI Jianfen chen Yongsheng WANG Hong Tianjin Center of Geological Survey China Geological Survey(CGS)CGS Key Laboratory of Muddy Coast Geoenvironment

Paleoenvironmental reconstruction is fundamental to understand the modern environmental changes and to predict future environment, which is especially critical to understand the evolution of land and sea during geological periods. However, the basic geological research on China＇s muddy coastal zone is not enough to provide quantitative data to compare with global changes. Therefore, in 2011, China Geological Survey deployed the ＂Late Quaternary geo-environmental evolution and modern process of China＂ project, and focused on the muddy coastal zones of the Liaodong Bay, Bohai Bay, the Yellow River Delta, Yangtze River Delta and Pearl River Delta （Fig. 1）. Next we will briefly introduce our latest results in the Bohai Bay.

关键词： BP area rate The Late Quaternary Coastal Geo-Environment Evolution and Modern Process of Bohai Bay,China Bay

Zonal extraction technology and numerical simulation analysis in open pit coal mine

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International Journal of Mining Science and Technology 2012年第4期22卷 487-491页

作者： chen Yanlong Cai Qingxiang shang Tao Peng Hongge Zhou Wei chen Shuzhao School of Mines China University of Mining&TechnologyXuzhou 221116China Department of Earth Resources Engineering Faculty of EngineeringKyushu UniversityFukuoka 819-0395Japan

In order to enhance coal recovery ratio of open pit coal mines, a new extraction method called zonal mining system for residual coal around the end-walls is presented. The mining system can improve economic benefits by exploiting haulage and ventilation roadways from the exposed position of coal seams by uti- lizing the existing transportation systems. Moreover, the main mining parameters have also been dis- cussed. The outcome shows that the load on coal seam roof is about 0.307 MPa and the drop step of the coal seam roof about 20.3 m when the thickness of cover and average volume weight are about 120 m and 0.023 MN/m~ respectively. With the increase of mining height and width, the coal recovery ratio can be improved. However, when recovery ratio is more than 0.85, the average stress on the coal pillar will increase tempestuously, so the recovery ratio should also be controlled to make the coal seam roof safe. Based on the numerical simulation results, it is concluded that the ratio of coal pillar width to height should be more than 1.0 to make sure the coal pillars are steady, and there are only minor dis- placements on the end-walls.

关键词： Extraction technologyNumerical simulationZonal miningResidual coalEnd-walls

OTFS Modulation and PAPR Reduction for IoT-Railways

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China Communications 2023年第1期20卷 102-113页

作者： Huichao shang Ruifeng chen Haoxiang Zhang Guoyu Ma Ruisi He Bo Ai Zhangdui Zhong State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China Institute of Computing Technologies China Academy of Railway Sciences Co.Ltd.Beijing 100081China China Academy of Industrial Internet Ministry of Industry and Information TechnologyBeijing 100804China

The internet of things(IoT)has been widely considered to be integrated with high-speed railways to improve safety and *** is important to achieve reliable communication in IoT for railways(IoT-R)under high mobility scenarios and strict energy *** time frequency space(OTFS)modulation is a two-dimensional modulation technique that has the potential to overcome the challenges in high Doppler *** addition,OTFS can have lower peak-to-average power ratio(PAPR)compared to orthogonal frequency division multiplexing,which is especially important for the application of ***,OTFS modulation for IoT-R is investigated in this *** order to decrease PAPR of OTFS and promote the application of OTFS modulation in IoT-R,the peak windowing technique is used in this *** technique can reduce the PAPR of OTFS by reducing the peak power and does not require multiple *** impacts of different window functions,window sizes and clipping levels on PAPR and bit error rate of OTFS are simulated and *** simulation results show that the peak windowing technique can efficiently reduce the PAPR of OTFS for IoT-R.

关键词： internet of things for railways(IoT-R) orthogonal time frequency space(OTFS) peak-toaverage power ratio(PAPR) peak windowing

Carbon-supported high-entropy Co-Zn-Cd-Cu-Mn sulfide nanoarrays promise high-performance overall water splitting

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Nano Research 2022年第7期15卷 6054-6061页

作者： Yuanting Lei Lili Zhang Wenjing Xu chengli Xiong Wenxing chen Xu Xiang Bing Zhang Huishan shang School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Transition metal sulfides with homogeneous multi-metallic elements promise high catalytic performance for water electrolysis owing to the unique structure and highly tailorable electrochemical *** existing synthetic routes require high temperature to ensure the uniform mixing of various elements,making the synthesis highly ***,for the first-time novel carbon fiber supported high-entropy Co-Zn-Cd-Cu-Mn sulfide(CoZnCdCuMnS@CF)nanoarrays are fabricated by the mild cation exchange *** from the synergistic effect among multiple metals and the strong interfacial bonding between high-entropy Co-Zn-Cd-Cu-Mn sulfide nanoarrays and the carbon fiber support,CoZnCdCuMnS@CF exhibits superior catalytic activity and stability toward overall water splitting in alkaline ***,CoZnCdCuMnS@CF only needs low overpotentials of 173 and 220 mV to reach the current density of 10 mA•cm^(−2),with excellent durability for over 70 and 113 h for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)*** importantly,the bifunctional electrode(CoZnCdCuMnS@CF||CoZnCdCuMnS@CF)for overall water splitting can deliver a small cell voltage of 1.63 V to afford 10 mA•cm^(−2) and exhibit outstanding stability of negligible decay after 73 h continuous *** work provides a viable synthesis route toward advanced high-entropy materials with great potential applications.

关键词： electrocatalysis high-entropy metal sulfides oxygen evolution reaction hydrogen evolution reaction low-temperature cation exchange

Dense ceramics with complex shape fabricated by 3D printing:A review

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Journal of Advanced Ceramics 2021年第2期10卷 195-218页

作者： Zhe chen Xiaohong Sun Yunpeng shang Kunzhou Xiong Zhongkai Xu Ruisong Guo Shu Cai Chunming Zheng School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin300072China School of Chemistry and Chemical Engineering State Key Laboratory of Hollow-fiber Membrane Materials and Membrane ProcessesTiangong UniversityTianjin300387China

Three-dimensional(3D)printing technology is becoming a promising method for fabricating highly complex ceramics owing to the arbitrary design and the infinite combination of *** density is one of the main problems with 3D printed ceramics,but concentrated descriptions of making dense ceramics are *** review specifically introduces the principles of the four 3D printing technologies and focuses on the parameters of each technology that affect the densification of 3D printed ceramics,such as the performance of raw materials and the interaction between energy and *** technical challenges and suggestions about how to achieve higher ceramic density are presented *** goal of the presented work is to comprehend the roles of critical parameters in the subsequent 3D printing process to prepare dense ceramics that can meet the practical applications.

关键词： 3D printing dense ceramics particle characteristics process parameters

Effects of functional phylogeny of light-response-related orthologous genes on seedling survival in a subtropical forest

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Forest Ecosystems 2023年第1期10卷 31-36页

作者： Hui shang Yunquan Wang Baocai Han Xiangcheng Mi Lei chen Yu Liang Keping Ma State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China shanghai chenshan Plant Science Research Center Chinese Academy of SciencesShanghai Chenshan Botanical GardenShanghai 201602China College of Chemistry and Life Sciences Zhejiang Normal UniversityJinhua 321004China State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China

Background: Light is an important environmental factor affecting the growth and survival of plants in forest communities. The competition for light resources and divergent responses to light may affect plant species coexistence in natural forests through niche partitioning and environmental filtering, ***: In the present study, sequences of light-response-related functional genes were extracted from transcriptomic data of 99 tree species in a subtropical forest and average and nearest taxon phylogenetic diversity of adult(A_Apd’, A_NTpd’) and seedling neighbors(S_Apd’, S_NTpd’) around each focal seedling were calculated to evaluate effects of differentiation in light-response-related genes on community assembly ***: The results showed that seedling survival was related to S_NTpd’, S_Apd’and A_Apd’of two chlorophyll ab-binding proteins involved in the assembly of photosystem Ⅱ and two genes responsive to light intensity,indicating seedlings surrounded by neighbors with distinct light responses tended to have high survival ***: Our results indicated that niche partitioning due to competition for light resources between plants may act as the key mechanism in determining seedling dynamics in subtropical forests.

关键词： Species co-existence Forest communities Neighbor effects Community genomics Negative density dependence Niche partitioning

Enhanced efficiency of graphene-silicon Schottky junction solar cell through inverted pyramid arrays texturation

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Journal of Materials Science & Technology 2018年第11期34卷 2197-2204页

作者： Jiajia Qiu Yudong shang Xiuhua chen Shaoyuan Li Wenhui Ma Xiaohan Wan Jia Yang Yun Lei Zhengjie chen State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and Technology Faculty of Physical Science and Technology Yunnan University Institute of New Energy/Silicon Metallurgy and Silicon Material Engineering Research Center of Universities in Yunnan Province Kunming University of Science and Technology

Nanostructures of silicon are gradually becoming hot candidate due to outstanding capability for trapping light and improving conversion efficiency of solar cell. In this paper, silicon nanowires（SiNWs） and silicon inverted pyramid arrays（SiIPs） were introduced on surface of Gr-Si solar cell through silver and copper-catalyzed chemical etching, respectively. The effects of SiNWs and SiIPs on carrier lifetime, optical properties and efficiency of Gr-SiNWs and Gr-SiIPs solar cells were systematically analyzed. The results show that the inverted pyramid arrays have more excellent ability for balancing antireflectance loss and surface area enlargement. The power conversion efficiency（PCE） and carrier lifetime of Gr-SiIPs devices respectively increase by 62% and 34% by comparing with that of Gr-SiNWs solar cells. Finally, the Gr-SiIPs cell with PCE of 5.63% was successfully achieved through nitric acid doping. This work proposes a new strategy to introduce the inverted pyramid arrays for improving the performance of Gr-Si solar cells.

关键词： Graphene-Si solar cell Silver/copper-assisted chemical etching Silicon nanowires Silicon inverted pyramid arrays

Evaluating the methodology of studies conducted during the global COVID-19 pandemic: A systematic review of randomized controlled trials

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Journal of Integrative Medicine 2021年第4期19卷 317-326页

作者： Meng-zhu Zhao chen Zhao Shuang-shuang Tu Xu-xu Wei Hong-cai shang Department of Cardiology First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300381China National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300381China Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical SciencesBeijing 100700China Editorial Department of Journals Tianjin University of Traditional Chinese MedicineTianjin 301617China Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing Dongzhimen Hospital Affiliated to Beijing University of Chinese MedicineBeijing 100700China International Evidence-based Research Institute of Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China

Background: The therapeutic evidence collected from well-designed studies is needed to help manage the global pandemic of the coronavirus disease 2019(COVID-19). Evaluating the quality of therapeutic data collected during this most recent pandemic is important for improving future clinical research under similar ***: To assess the methodological quality and variability in implementation of randomized controlled trials(RCTs) for treating COVID-19, and to analyze the support that should be provided to improve data collected during an urgent pandemic *** strategy: Pub Med, Excerpta Medica Database, China National Knowledge Infrastructure, Wanfang,and Chongqing VIP, and the preprint repositories including Social Science Research Network and Med Rxiv were systematically searched, up to September 30, 2020, using the keywords "coronavirus disease 2019(COVID-19)," "2019 novel coronavirus(2019-n Co V)," "severe acute respiratory syndrome-related coronavirus-2(SARS-Co V-2)," "novel coronavirus pneumonia(NCP)," "randomized controlled trial(RCT)" and "random."Inclusion criteria: RCTs studying the treatment of COVID-19 were eligible for *** extraction and analysis: Screening of published RCTs for inclusion and data extraction were each conducted by two researchers. Analysis of general information on COVID-19 RCTs was done using descriptive statistics. Methodological quality was assessed using the risk-of-bias tools in the Cochrane Handbook for Systematic Reviews of Interventions(Version 5.1.0). Variability in implementation was assessed by comparing consistency between RCT reports and registration ***: A total of 5886 COVID-19 RCTs were identified. Eighty-one RCTs were finally included, of which,45 had registration information. Methodological quality of the RTCs was not optimal due to deficiencies in five main domains: allocation concealment, blinding of participants and personnel, blinding of outcome assessment, incomp

关键词： COVID-19 Randomized controlled trial Therapeutic evidence Methodology Systematic review