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Chinese pangolins (Manis pentadactyla) are not functionally extinct in China 被引量:1
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作者 Zhi-Cheng Liu peng cen +4 位作者 Jian-Kun Sun Fu-Hua Zhang Amna Mahmood Chen Lei Shi-Bao Wu 《Zoological Research(Diversity and Conservation)》 2024年第1期79-81,共3页
DEAR EDITOR,The key features of functional extinction include continuous reproductive failure,lack of new recruitment,and persistent population decline(Jarićet al.,2016;Roberts et al.,2017).However,the conclusion of f... DEAR EDITOR,The key features of functional extinction include continuous reproductive failure,lack of new recruitment,and persistent population decline(Jarićet al.,2016;Roberts et al.,2017).However,the conclusion of functional extinction for the Chinese pangolin(Manis pentadactyla)by the China Biodiversity Conservation and Green Development Foundation(CBC-GDF)based on preliminary field information is unconvincing as they did not assess reproductive function or new individual recruitment of Chinese pangolin populations(Supplementary Materials). 展开更多
关键词 EXTINCTION Roberts Manis
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资源依赖、政府廉政水平与绿色技术创新——来自中国资源型城市的经验证据 被引量:10
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作者 秦炳涛 彭涔 +1 位作者 葛力铭 俞勇伟 《中国环境科学》 EI CAS CSCD 北大核心 2023年第7期3835-3847,共13页
基于2000~2017年我国资源型城市面板数据,综合采用固定效应模型、中介效应模型、调节效应模型与工具变量法等多种计量分析方法,实证分析了资源依赖对资源型城市绿色技术创新的影响及其作用机制.结果表明,资源依赖显著抑制了资源型城市... 基于2000~2017年我国资源型城市面板数据,综合采用固定效应模型、中介效应模型、调节效应模型与工具变量法等多种计量分析方法,实证分析了资源依赖对资源型城市绿色技术创新的影响及其作用机制.结果表明,资源依赖显著抑制了资源型城市的绿色技术创新,这一结论在经过一系列稳健性检验以及控制内生性问题后依然成立.机制分析表明,资源依赖会通过降低政府清廉水平,进而抑制资源型城市的绿色技术创新.异质性分析表明,资源依赖通过降低政府廉政水平抑制绿色技术创新存在显著的地区差异,资源依赖的挤出效应仅在高腐败城市、高资源依赖城市、中小城市和传统矿业类城市显著,政府廉政水平这一中介机制在扩张型资源型城市发挥了更为明显的作用,而再生型资源型城市产业结构多元,资源依赖正向影响绿色技术创新.政府规模过大降低政府廉政水平的同时,对资源依赖影响绿色技术创新起负向调节作用. 展开更多
关键词 资源依赖 政府廉政水平 绿色技术创新 资源型城市
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基于OBE理念的SPOC教学在老年心内科护理教学中的应用 被引量:2
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作者 彭岑 喻卓 +1 位作者 胡伟 宋文红 《中国继续医学教育》 2022年第18期91-95,共5页
目的探讨基于成果导向教育(outcome based education,OBE)理念小规模限制性在线课程(small private online course,SPOC)教学在老年心内科护理教学中的应用价值。方法纳入2020年1—12月100名接受老年心内科临床护理教学的护生作为研究... 目的探讨基于成果导向教育(outcome based education,OBE)理念小规模限制性在线课程(small private online course,SPOC)教学在老年心内科护理教学中的应用价值。方法纳入2020年1—12月100名接受老年心内科临床护理教学的护生作为研究对象。按照随机数字表对照法分为两组,每组50名。对照组接受常规护理教学,观察组接受基于OBE理念的SPOC教学。比较两组护生教学结束后心内科理论知识考核结果、技能操作考核结果、综合素质考核结果以及对教学模式的满意度差异。结果观察组护生心内科理论知识与技能操作考核成绩均高于对照组,差异有统计学意义(P<0.05)。观察组护生交流沟通能力、问题分析和解决能力、主观能动性及应急反应考核成绩均高于对照组,差异有统计学意义(P<0.05)。观察组护生对激发学习兴趣、培养自主学习能力、提高理解能力、巩固深化理论知识、提高操作技能的满意度均高于对照组,差异有统计学意义(P<0.05)。结论基于OBE理念的SPOC教学能够提高老年心内科临床护理教学效果,护生满意度较高,值得临床推荐。 展开更多
关键词 老年心内科 临床护理教学 OBE理念 SPOC教学 理论知识考核 技能操作考核 综合素质考核
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Characterization and ultraviolet-visible shielding property of samarium-cerium compounds containing Sm_(2)O_(2)S prepared by co-precipitation method 被引量:1
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作者 Yanping Li Xue Bian +3 位作者 Xun Jin peng cen Wenyuan Wu Gaofeng Fu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第9期1809-1816,共8页
Since ultraviolet(UV)light,as well as blue light,which is part of visible light,is harmful to skin,samarium-cerium compounds containing Sm_(2)O_(2)S were synthesized by co-precipitation method.This kind of compounds b... Since ultraviolet(UV)light,as well as blue light,which is part of visible light,is harmful to skin,samarium-cerium compounds containing Sm_(2)O_(2)S were synthesized by co-precipitation method.This kind of compounds blocks not only UV light,but also blue light.The minimum values of average transmittance(360-450 nm)and band gap of samarium-cerium compounds were 8.90%and 2.76 eV,respectively,which were less than 13.96%and 3.01 eV of CeO_(2).Elemental analysis(EA),X-ray diffraction(XRD),Fourier transformation infrared(FTIR),and Raman spectra determined that the samples contained Ce_(4)O_(7),Sm_(2)O_(2)S,Sm_(2)O_(3),and Sm_(2)O_(2)SO_(4).The microstructure of samples was analyzed by scanning and transmission electron microscopies(SEM and TEM).X-ray photoelectron spectrum(XPS)showed that cerium had Ce^(3+)and Ce^(4+) valence states,and oxygen was divided into lattice oxygen and oxygen vacancy,which was the direct cause of the decrease of average transmittance and band gap. 展开更多
关键词 band gap co-precipitation method samarium-cerium compound ultraviolet light blue light
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Sentiment Analysis Using Deep Learning Approach 被引量:2
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作者 peng cen Kexin Zhang Desheng Zheng 《Journal on Artificial Intelligence》 2020年第1期17-27,共11页
Deep learning has made a great breakthrough in the field of speech and image recognition.Mature deep learning neural network has completely changed the field of natural language processing(NLP).Due to the enormous amo... Deep learning has made a great breakthrough in the field of speech and image recognition.Mature deep learning neural network has completely changed the field of natural language processing(NLP).Due to the enormous amount of data and opinions being produced,shared and transferred everyday across the Internet and other media,sentiment analysis has become one of the most active research fields in natural language processing.This paper introduces three deep learning networks applied in IMDB movie reviews sentiment analysis.Dataset was divided to 50%positive reviews and 50%negative reviews.Recurrent Neural Network(RNN)and Long Short-Term Memory(LSTM)neural networks are two main types,which are widely used in NLP tasks,while Convolutional Neural Networks(CNN)is often used in image recognition.The results have shown that,CNN network model can achieve good classification effect when applied to sentiment analysis of movie reviews.CNN have reported the accuracy of 88.22%,while RNN and LSTM have reported accuracy of 68.64%and 85.32%respectively. 展开更多
关键词 Deep learning RNN LSTM CNN sentiment analysis
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Electrochemical properties of LiNi_(0.5)Mn_(1.3)Ti_(0.2)O_4/Li_4Ti_5O_(12)cells
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作者 Guo-qiang Liu Xi Wang +5 位作者 Ya-jie Gao Lei Wen Guang-yin Liu Jian-jie Zheng peng cen Ying Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第5期457-460,共4页
Spinel compounds LiNi0.5Mn1.3Ti0.2O4(LNMTO) and Li4Ti5O12 (LTO) were synthesized by different methods. The particle sizes of LNMTO and LTO are 0.5-2 and 0.5-0.8 μm, respectively. The LNMTO/LTO cell exhibits bette... Spinel compounds LiNi0.5Mn1.3Ti0.2O4(LNMTO) and Li4Ti5O12 (LTO) were synthesized by different methods. The particle sizes of LNMTO and LTO are 0.5-2 and 0.5-0.8 μm, respectively. The LNMTO/LTO cell exhibits better electrochemical properties at both a low current rate of 0.2C and a high current rate of 1C. When the specific capacity was determined based on the mass of the LNMTO cathode, the LNMTO/LTO cell delivered 137 mA.h.g-1 at 0.2C and 118.2 mA-h-g-l at 1C, and the corresponding capacity retentions after 30 cycles are 88.5% and 92.4%, respectively. 展开更多
关键词 lithium batteries titanium compounds nickel compounds manganese compounds OXIDES electrochemical properties
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Isoconversional kinetic analysis of decomposition of bastnaesite concentrates with calcium hydroxide 被引量:4
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作者 peng cen Xue Bian Wenyuan Wu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第12期1361-1371,共11页
Isoconversional methods combined with thermogravimetry were applied to investigate the decomposition kinetics of bastnaesite concentrates with different amounts of calcium hydroxide added.The apparent activation energ... Isoconversional methods combined with thermogravimetry were applied to investigate the decomposition kinetics of bastnaesite concentrates with different amounts of calcium hydroxide added.The apparent activation energy was calculated,and the results indicate that the overall reaction involves more than one single step.The reaction with a lower content(<15 wt%)of calcium hydroxide can be divided into two steps,while the reaction with a higher content(>15 wt%)involves another step which denotes the decomposition of newly formed calcium carbonate during roasting.The activation energy increases with increasing amount of calcium hydroxide in the lower range(0-15 wt%).This is due to the resistance of calcium hydroxide to heat and mass transport,However,more calcium can promote the decomposition reaction more effectively and thus reduce the activation energy.Nonlinear fitting was performed by fitting the experimental data to Avrami-Erofeev model to determine the reaction model and pre-exponential factor.The theoretical models were proven to be reliable for kinetic prediction. 展开更多
关键词 BASTNAESITE Thermal analysis kinetics Isoconversional method Calcium hydroxide Rare earths
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穿山甲肉在中国内地的非法贸易网络及对其实施关键干预措施的启示
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作者 张富华 席菲 +2 位作者 汤芯蕊 岑鹏 吴诗宝 《生物多样性》 CSCD 北大核心 2023年第10期83-94,共12页
中国是穿山甲(Manis spp.)肉及甲片的主要消费区域之一。针对穿山甲不同形式产品的非法贸易和消费特点制定差异化、精准的保护对策,对于穿山甲物种保护具有重要的促进作用。然而,目前缺乏分别对穿山甲的肉或甲片开展非法贸易和消费特点... 中国是穿山甲(Manis spp.)肉及甲片的主要消费区域之一。针对穿山甲不同形式产品的非法贸易和消费特点制定差异化、精准的保护对策,对于穿山甲物种保护具有重要的促进作用。然而,目前缺乏分别对穿山甲的肉或甲片开展非法贸易和消费特点的研究。本研究通过使用关键词“穿山甲”检索2022年1月11日之前在中国裁判文书网和网络媒体上报道的穿山甲肉的非法贸易案例,对其涉及区域、贸易网络特征及贸易方式等进行了研究。结果发现,穿山甲肉的贸易和消费主要集中在中国南方地区;这些肉主要是由东南亚地区输入我国,少量可能来自查获地。防城港、保山以及德宏是穿山甲肉非法贸易入境的主要陆路通道,而广东和福建的港口和小码头是主要的海运通道。国内防城港、广州和昆明是穿山甲非法贸易网络上的关键城市。本研究的结果可能会受到2013年之前裁判文书网相应案件收录不全以及越久远的网络报道案例丢失越多的数据偏差的影响。根据本研究结果,我们建议:加强中国广西、云南边境口岸以及广东、福建港口、小码头等的货物走私检查和监察力度,提高防城港、广州、保山和德宏出境车辆货物检查率,在中国南方和北方采取差异化的穿山甲保护公众教育措施,同时呼吁东南亚国家加强野生动物保护立法、执法力度和公众教育等措施,是有效遏制中国内地穿山甲肉非法贸易和消费的手段。本研究对于中国的穿山甲物种保护具有较大的实践意义。 展开更多
关键词 非法贸易 穿山甲肉 走私 动物保护 中国内地
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Only Sunda and Chinese pangolin(Pholidota)are naturally distributed in China 被引量:1
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作者 peng cen Jiankun SUN +6 位作者 Qiaoyan WANG Fuhua ZHANG Lianxian MO Amna MAHMOOD Jiaqi LI Yifu WANG Shibao WU 《Integrative Zoology》 SCIE CSCD 2023年第4期704-709,共6页
INTRODUCTION Pangolin is the common name for animals in the Family Pholidota,Mammalia,which consists of eight extant species.All pangolin species have been listed as critically endangered(CR),endangered(EN),or vulnera... INTRODUCTION Pangolin is the common name for animals in the Family Pholidota,Mammalia,which consists of eight extant species.All pangolin species have been listed as critically endangered(CR),endangered(EN),or vulnerable(VU)species in the International Union for Conservation of Nature(IUCN)Red List of Threatened Species(Challender et al.2020).In June 2020,the Chinese government upgraded the Chinese pangolin(Manis pentadactyla Linnaeus,1758)from a national second-class protected animal to a national first-class protected animal.In February 2021,the Sunda pangolin(Manis javanica Desmarest,1822)and the Indian pangolin(Manis crassicaudata Geoffroy,1803)were added to the list of national first-class protected animals.However,the number of species of pangolins naturally distributed in China varies in the literature:Some sources have recorded only one species,namely the Chinese pangolin(Nowak&Paradiso 1983;Sheng 1999),while most have recorded two species,namely the Chinese pangolin and Indian pangolin(Allen 1938;Zhang 1997;Wang 2003;Wu et al.2005a;Hu&Hu 2017). 展开更多
关键词 protected INDIAN LISTED
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