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“三鹿奶粉”事件引起的思考——以成本与利润问题分析为例

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天津大学学报（社会科学版） 2010年第2期12卷 129-132页

作者：于富生梁帆中国人民大学会计系北京10872 北京大学考古文博学院北京100871

"三鹿奶粉"重大食品安全事故,已导致全国近5万名婴幼儿患病,并一度造成广大社会民众对食品安全的极度恐慌。"三鹿奶粉"事件不但使中国食品行业发展遭遇重创,引发了整个中国食品行业的安全信任危机,而且在世界范围内再次掀起对"中国制造... 详细信息

"三鹿奶粉"重大食品安全事故,已导致全国近5万名婴幼儿患病,并一度造成广大社会民众对食品安全的极度恐慌。"三鹿奶粉"事件不但使中国食品行业发展遭遇重创,引发了整个中国食品行业的安全信任危机,而且在世界范围内再次掀起对"中国制造"问题的热议。"三鹿奶粉"事件产生的原因是多方面的,但主要归结于奶粉监督管理部门的规章制度不完善和监管不力以及企业道德失范、责任不明确或责任心不强等原因。而笔者力求利用经济学原理,从成本与利润分析这一新的视角出发,探讨奶制品行业造假贩假的本源,探索揭示"三鹿奶粉"事件发生的内在必然性,并提出相应的对策。

关键词： “三鹿奶粉”事件恶性竞争成本与利润

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东濮凹陷构造变形的物理模拟研究

地球学报 2017年第3期38卷 430-438页

作者：马宝军漆家福于福生河北地质大学资源学院河北石家庄050031 中国石油大学(北京)地球科学学院北京102249

东濮凹陷是一个研究程度较高的含油气区,前人在构造变形研究方面多注重于伸展变形的几何学分析而忽略了形成机制中走滑分量的作用。本文在对区域地质背景和东濮凹陷构造特征分析基础上,设计平、剖面砂箱实验对该凹陷的构造变形进行伸展... 详细信息

东濮凹陷是一个研究程度较高的含油气区,前人在构造变形研究方面多注重于伸展变形的几何学分析而忽略了形成机制中走滑分量的作用。本文在对区域地质背景和东濮凹陷构造特征分析基础上,设计平、剖面砂箱实验对该凹陷的构造变形进行伸展-走滑模拟研究。结果表明:(1)具走滑性质的断裂组合形成的构造样式更加复杂多样,走滑断层弯曲会产生挤压或伸展分量,在相邻的区域内形成局部的凹陷和隆起,主动盘的不同会形成不同的断裂组合;(2)在区域NNW—SSE向伸展变形下,形成了东濮凹陷两洼一凸的近对称格局,基底深断裂的张扭性开裂加速了凹陷的形成,主断层上、下盘均有明显的活动;(3)受基底断裂活动影响,大约Es^2-Ed沉积期凹陷存在一个明显的右旋走滑变形期,在凹陷的中部隆起带上出现了负花状、火焰状等典型走滑构造样式,走滑变形具有阵发性特点。

关键词：构造变形物理模拟沙箱实验基底走滑断裂东濮凹陷

The etching strategy of zinc anode to enable high performance zinc-ion batteries

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Journal of Energy Chemistry 2024年第1期88卷 125-143,I0004页

作者： Xueqing fu Gaopeng Li Xinlu Wang Jinxian Wang Wensheng yu Xiangting Dong Dongtao Liu School of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130022JilinChina Department of Chemistry Northeast Normal UniversityChangchun 130024JilinChina

Zinc-ion batteries(ZIBs)are considered to be one of the most promising candidates to replace lithium-ion batteries(LIBs)due to the high theoretical capacity,low cost and intrinsic ***,zinc dendrites,hydrogen evolution reaction,surface passivation and other side reactions will inevitably occur during the charging and discharging process of Zn anode,which will seriously affect the cycle stability of the battery and hinder its practical *** etching strategy of Zn anode has attracted wide attention because of its simple operation and broad commercial prospects,and the etched Zn anode can effectively improve its electrochemical ***,there is no comprehensive review of the etching strategy of Zn *** review first summarizes the challenges faced by Zn anode,then puts forward the etching mechanisms and properties of acid,salt and other ***,based on the above discussion,the challenges and opportunities of Zn anode etching strategy are proposed.

关键词： Zinc-ion batteries Zn anode Etching 3D structures Dendrite-free

Response of ocean acidification to atmospheric carbon dioxide removal

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Journal of Environmental Sciences 2024年第6期140卷 79-90页

作者： Jiu Jiang Long Cao Xiaoyu Jin Zechen yu Han Zhang Jianjie fu Guibin Jiang School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Key Laboratory of Geoscience Big Data and Deep Resources of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhou 310058China Zhejiang Climate Center Hangzhou 310052China

Artificial CO_(2)removal from the atmosphere(also referred to as negative CO_(2)emissions)has been proposed as a potential means to counteract anthropogenic climate *** we use an Earth system model to examine the response of ocean acidification to idealized atmospheric CO_(2)removal *** our simulations,atmospheric CO_(2)is assumed to increase at a rate of 1%per year to four times its pre-industrial value and then decreases to the pre-industrial level at a rate of 0.5%,1%,2%per year,*** results show that the annual mean state of surface ocean carbonate chemistry fields including hydrogen ion concentration([H^(+)]),pH and aragonite saturation state respond quickly to removal of atmospheric CO_(2).However,the change of seasonal cycle in carbonate chemistry lags behind the decline in atmospheric CO_(2).When CO_(2)returns to the pre-industrial level,over some parts of the ocean,relative to the pre-industrial state,the seasonal amplitude of carbonate chemistry fields is substantially *** results also show that changes in deep ocean carbonate chemistry substantially lag behind atmospheric CO_(2)*** CO_(2)returns to its pre-industrial value,the whole-ocean acidity measured by[H^(+)]is 15%-18%larger than the pre-industrial level,depending on the rate of CO_(2)*** study demonstrates that even if atmospheric CO_(2)can be lowered in the future as a result of net negative CO_(2)emissions,the recovery of some aspects of ocean acidification would take decades to centuries,which would have important implications for the resilience of marine ecosystems.

关键词： Carbon dioxide removal Net negative CO_(2)emission Ocean acidification Climate change Earth system modeling

Wireless electrical stimulation generated by piezoelectric nanomaterial promotes the dental pulp regeneration via regulating mitochondrial Ca^(2+)/PKA signaling pathway

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Journal of Materials Science & Technology 2024年第1期168卷 24-34页

作者： Jianmao Zheng Jiyuan Zuo Cairong Xiao Qining Guo Xiaobin fu Chengyun Ning Peng yu Guangdong Provincial Key Laboratory of Stomatology Hospital of StomatologySun Yat-Sen UniversityGuangzhou 510080China School of Materials Science and Engineering National Engineering Research Center for Tissue Restoration and ReconstructionSouth China University of TechnologyGuangzhou 510641China

The induction of dental pulp stem cells(DPSCs)into odontogenic differentiation is a cutting-edge method of dental pulp regeneration ***,it remains a challenge to develop biomaterials and ther-apies that can induce odontogenic ***,we propose a wireless electrical stimulation strat-egy to induce DPSCs odontogenic differentiation via K_(0.5)Na_(0.5)NbO_(3)piezoelectric nanoparticles(KNN)and polarized KNN(PKNN),which can be endocytosed by *** vitro,several odontogenic differentiation indexes were also increased in DPSCs treated with KNN and PKNN,and the increase was more obvious in the PKNN *** wireless electrical field promoted mitochondrial calcium concentration via mitochondrial calcium unidirectional transporter(MCU),increased the production of adenosine triphos-phate(ATP),and induced odontogenic differentiation through the activation of the cAMP-PKA signaling *** vivo,dental pulp-like tissue was induced by electrical stimulation wirelessly with KNN and PKNN,which was more clinically friendly compared with the wired device,and the induction was more obvious in the PKNN group consistent with in vitro *** conclusion,this work demonstrates the potential of PKNN as an effective stimulus that can induce odontogenic differentiation of DPSCs and be applied to dental pulp regeneration treatment.

关键词： Piezoelectric nanoparticles Dental pulp stem cells Odontogenic differentiation

Elastohydrodynamic Lubrication Interface Stiffness and Damping Considering Asperity Lateral Contact

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Acta Mechanica Solida Sinica 2024年第1期37卷 109-123页

作者： Zhiqiang Gao yu Zhang Xian Wei Yanfang Zhu Lixia Peng Weiping fu Wen Wang School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048China School of Intelligent Manufacturing Panzhihua UniversityPanzhihua 617000China Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Light Chemical TechnologyYibin 644002China School of Mechanical Engineering Anyang Institute of TechnologyAnyang 455099China

Elastohydrodynamic lubrication(EHL)point contact occurs between two rough surfaces at the mesoscopic level,while the interaction of rough surfaces involves contact between asperities at the microscale *** most cases,the contact between asperities within an interface takes the form of lateral contact rather than peak *** devoid of contact asperities are filled with lubricating ***,conventional models often oversimplify lateral contact forms as interactions between asperities and a smooth,rigid *** simplifications fail to accurately represent the true contact conditions and can lead to inaccuracies in the analysis of EHL’s contact *** address this issue,we have developed a novel EHL interface model comprising two rough *** model allows us to explore the influence of asperity height,contact angle,and contact azimuth angle on EHL interface performance.

关键词： EHL interface Asperity lateral contact Contact stiffness Damping

Multivariate chemical analysis:From sensors to sensor arrays

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Chinese Chemical Letters 2024年第7期35卷 14-24页

作者： Xueling yu Lixing fu Tong Wang Zhixin Liu Na Niu Ligang Chen College of Chemistry Chemical Engineering and Resource UtilizationKey Laboratory of Forest Plant EcologyNortheast Forestry UniversityHarbin 150040China

Chemical sensor arrays can obtain more comprehensive analyte information through high-dimensional *** is of great significance in the analysis of multi-component complex *** review summarizes the development and status of chemical sensor *** focused on the design of chemical sensor arrays based on various sensing *** addition,several pattern recognition methods in chemometrics are *** applications of chemical sensor arrays in food monitoring,medical diagnosis,and environmental monitoring are *** on the analysis of the limitations of current sensor array technology,the direction of the array is also *** review aims to help the broad readership understand the research state of chemical sensor arrays and their development prospects.

关键词： Chemical sensor arrays Sensing materials Pattern recognition methods Analytical application

Metal-to-insulator transition in platinum group compounds

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Rare Metals 2024年第8期43卷 3460-3474页

作者： yu-Xuan Xia Jian-Gang He Nuo-fu Chen Ji-Kun Chen School of New Energy North China Electric Power UniversityBeijing102206China School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China Key Laboratory of Advanced Materials and Devices for PostMoore Chips(Ministry of Education) School of Materials Science and EngineeringJniversity of Science and Technology BeijingBeijing 100083China

The metal-to-insulator transition(MIT) as usually achieved in 3d-orbital transitional metal(TM) compounds opens up a new paradigm in correlated electronics via triggering abrupt variations in their transportation *** to such 3d-orbital TM compounds,the MIT within the platinum group(Pg) element compounds based on the 4d-and 5d-orbital configurations is more complicated,owing to their elevation in the spinorbit coupling and meanwhile weakened intra-atomic Coulomb *** brings in a new freedom to regulate the balance in their metallic or semiconductive orbital configurations,while their MIT properties can be potentially combined with their spintronic properties to enable new electronic ***,we review the electronic transport and MIT behaviors within the existing family of Pg-containing compounds,particularly those showing first-order MIT behaviors that can be useful in correlated *** is also hoped that summarizing the presently reported Pg-containing MIT compounds will lead to the discovery of more new material families and/or new mechanisms associated with the Pg-containing compounds showing MIT properties.

关键词： Metal-to-insulator transition Platinum group compounds Electron correlation Spin-orbital coupling

EvolveKG:a general framework to learn evolving knowledge graphs

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Frontiers of Computer Science 2024年第3期18卷 43-59页

作者： Jiaqi LIU Zhiwen yu Bin GUO Cheng DENG Luoyi fu Xinbing WANG Chenghu ZHOU School of Computer Science Northwestern Polytechnical UniversityXi’an 710129China Department of Computer Science Shanghai Jiao Tong UniversityShanghai 200240China Institute of Geographical Science and Natural Resources Research Chinese Academy of SciencesBejjing 100864China

A great many practical applications have observed knowledge evolution,i.e.,continuous born of new knowledge,with its formation influenced by the structure of historical *** observation gives rise to evolving knowledge graphs whose structure temporally grows over ***,both the modal characterization and the algorithmic implementation of evolving knowledge graphs remain *** this end,we propose EvolveKG–a general framework that enables algorithms in the static knowledge graphs to learn the evolving *** quantifies the influence of a historical fact on a current one,called the effectiveness of the fact,and makes knowledge prediction by leveraging all the cross-time knowledge *** novelty of EvolveKG lies in Derivative Graph–a weighted snapshot of evolution at a certain ***,each weight quantifies knowledge effectiveness through a temporarily decaying function of consistency and attenuation,two proposed factors depicting whether or not the effectiveness of a fact fades away with ***,considering both knowledge creation and loss,we obtain higher prediction accuracy when the effectiveness of all the facts increases with time or remains *** four real datasets,the superiority of EvolveKG is confirmed in prediction accuracy.

关键词： knowledge graph evolution modal characterization algorithmic implementation