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Physiological responses in vitamin C system during hibernation in juvenile Chinese soft-shelled turtle Pelodiscus sinensis

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Journal of Oceanology and Limnology 2019年第2期37卷 767-776,I0001-I0011页

作者： chen bojian NIU Cuijuan YUAN Lin ZHANG Wenyi College of Animal Science and Technology Northwest Agriculture and Forestry University Yangling 712100 China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life Sciences Beijing Normal University Beijing 100875 China

Vitamin C (Vc) is an important antioxidant that helps turtles tolerating stressful environment. This work quantified changes in tissue Vc levels during winter hibernation in the soft-shelled turtle Pelodiscus sinensis , to reveal the stress response pattern of tissue Vc during hibernation and contribute basic data for turtle culture. We sampled juvenile soft-shelled turtles at pre-hibernation (17.0°C mud temperature;MT), during hibernation (5.8°C MT) and after arousal (20.1°C MT) in the field. The transcript levels of the gene encoding L-gulonolactone oxidase (GLO), the key enzyme for Vc synthesis, decreased significantly during hibernation. However, GLO activity did not match the GLO transcription patterns and remained stable during hibernation, and showed temperature-dependent kinetic characteristics. Vitamin C levels in the brain, liver, kidney, and spleen (but not muscle) all decreased significantly during hibernation, but recovered to pre-hibernation levels or even higher levels after arousal. The soft-shelled turtle endured 5 months of hibernation with no significant oxidative damage in most tissues, except in the spleen. Splenic Vc was nearly exhausted during hibernation, accompanied by a significantly elevated malonaldehyde (MDA) level. Although the high level of oxidative damage quickly decreased after arousal, the potential tissue damage in the spleen during hibernation might account for the weakened immune capacity of turtles after hibernation.

关键词： Chinese soft-shelled turtle hibernation reactive oxygen species (ROS) L-gulonolactone oxidase oxidative stress

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Comparison of the interface reaction behaviors of CaO–V_(2)O_(5) and MnO_(2)–V_(2)O_(5) solid-state systems based on the diffusion couple method

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International Journal of Minerals,Metallurgy and Materials 2023年第5期30卷 834-843页

作者： Jing Wen Hongyan Sun Tao Jiang bojian chen Fangfang Li Mengxia Liu School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China Liaoning Key Laboratory for Metallurgical Sensor and Technology Shenyang 110819China

The formation mechanism of calcium vanadate and manganese vanadate and the difference between calcium and manganese in the reaction with vanadium are basic issues in the calcification roasting and manganese roasting process with vanadium *** this work,CaO–V_(2)O_(5) and MnO_(2)–V_(2)O_(5) diffusion couples were prepared and roasted for different time periods to illustrate and compare the diffusion reaction ***,the changes in the diffusion product and diffusion coefficient were investigated and calculated based on scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) *** show that with the extension of the roasting time,the diffusion reaction gradually proceeds among the CaO–V_(2)O_(5) and MnO_(2)–V_(2)O_(5) diffusion *** regional boundaries of calcium and vanadium are easily identifiable for the CaO–V_(2)O_(5) diffusion ***,for the MnO_(2)–V_(2)O_(5) diffusion couple,MnO_(2) gradually decomposes to form Mn_(2)O_(3),and vanadium diffuses into the interior of Mn_(2)O_(3).Only a part of vanadium combines with manganese to form the diffusion production ***_(2)O_(6) and MnV_(2)O_(6) are the interfacial reaction products of the CaO–V_(2)O_(5) and MnO_(2)–V_(2)O_(5) diffusion couples,respectively,whose thicknesses are 39.85 and 32.13μm when roasted for 16 *** 16 h,both diffusion couples reach the reaction equilibrium due to the limitation of *** diffusion coefficient of the CaO–V_(2)O_(5) diffusion couple is higher than that of the MnO_(2)–V_(2)O_(5) diffusion couple for the same roasting time,and the diffusion reaction between vanadium and calcium is easier than that between vanadium and manganese.

关键词： solid-state reaction reaction regularity of calcium and vanadium reaction regularity of manganese and vanadium diffusion couple method interface reaction behavior

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High-chromium vanadium-titanium magnetite all-pellet integrated burden optimization and softening-melting behavior based on flux pellets

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 498-507页

作者： bojian chen Tao Jiang Jing Wen Guangdong Yang Tangxia Yu Fengxiang Zhu Peng Hu School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China Liaoning Key Laboratory for Metallurgical Sensor and Technology Shenyang 110819China State key laboratory of vanadium and titanium resources comprehensive utilization Panzhihua 617000China

High-chromium vanadium-titanium magnetite(HVTM)is a crucial polymetallic-associated resource to be *** allpellet operation is a blast furnace trend that aims to reduce carbon dioxide emissions in the *** referencing the production data of vanadium-titanium magnetite blast furnaces,this study explored the softening-melting behavior of high-chromium vanadium-titanium magnetite and obtained the optimal integrated burden based on flux *** results show that the burden with a composition of 70wt%flux pellets and 30wt%acid pellets exhibits the best softening-melting *** comparison to that of the single burden,the softening-melting characteristic temperature of this burden composition was *** melting interval first increased from 307 to 362℃and then decreased to 282℃.The maximum pressure drop(ΔPmax)decreased from 26.76 to 19.01 *** permeability index(S)dropped from 4643.5 to 2446.8 kPa·℃.The softening-melting properties of the integrated burden were apparently *** acid pellets played a role in withstanding load during the softening *** flux pellets in the integrated burden exhibited a higher slag melting point,which increased the melting temperature during the melting *** slag homogeneity and the TiC produced by over-reduction led to the gas permeability deterioration of the single *** segregation of the flux and acid pellets in the HVTM proportion and basicity mainly led to the better softening-melting properties of the integrated burden.

关键词： high-chromium vanadium-titanium magnetite softening-melting properties all pellets integrated burden flux pellets

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Continual learning fault diagnosis:A dual-branch adaptive aggregation residual network for fault diagnosis with machine increments

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Chinese Journal of Aeronautics 2023年第6期36卷 361-377页

作者： bojian chen Changqing SHEN Juanjuan SHI Lin KONG Luyang TAN Dong WANG Zhongkui ZHU School of Rail Transportation Soochow UniversitySuzhou 215131China China Chang Guang Satellite Technology CO.LTD Changchun 130102China Department of Industrial Engineering and Management and in the State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200030China

As a data-driven approach, Deep Learning(DL)-based fault diagnosis methods need to collect the relatively comprehensive data on machine fault types to achieve satisfactory performance. A mechanical system may include multiple submachines in the real-world. During condition monitoring of a mechanical system, fault data are distributed in a continuous flow of constantly generated information and new faults will inevitably occur in unconsidered submachines, which are also called machine increments. Therefore, adequately collecting fault data in advance is difficult. Limited by the characteristics of DL, training existing models directly with new fault data of new submachines leads to catastrophic forgetting of old tasks, while the cost of collecting all known data to retrain the models is excessively high. DL-based fault diagnosis methods cannot learn continually and adaptively in dynamic environments. A new Continual Learning Fault Diagnosis method(CLFD) is proposed in this paper to solve a series of fault diagnosis tasks with machine increments. The stability–plasticity dilemma is an intrinsic issue in continual learning. The core of CLFD is the proposed Dual-branch Adaptive Aggregation Residual Network(DAARN).Two types of residual blocks are created in each block layer of DAARN: steady and dynamic blocks. The stability–plasticity dilemma is solved by assigning them with adaptive aggregation weights to balance stability and plasticity, and a bi-level optimization program is used to optimize adaptive aggregation weights and model parameters. In addition, a feature-level knowledge distillation loss function is proposed to further overcome catastrophic forgetting. CLFD is then applied to the fault diagnosis case with machine increments. Results demonstrate that CLFD outperforms other continual learning methods and has satisfactory robustness.

关键词： Catastrophic forgetting Continual learning Fault diagnosis Knowledge distillation Machine increments Stability-plasticity dilemma

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Antioxidant response to severe hypoxia in Brandt’s vole Lasiopodomys brandtii

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Integrative Zoology 2022年第4期17卷 581-595页

作者： Luye SHI bojian chen Xinrui WANG Maolin HUANG Congcong QIAO Jingou WANG Zhenlong WANG School of Life Sciences Zhengzhou UniversityZhengzhouChina State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingChina College of Environmental Science and Engineering Tongji UniversityShanghaiChina Jiaxing-Tongji Environmental Research Institute JiaxingChina Centre for Nutritional Ecology Zhengzhou UniversityZhengzhouChina

The antioxidant defense system is essential for animals to cope with homeostasis disruption and overcome oxidative stress caused by adverse environmental conditions such as ***,our understanding of how this system works in subterranean rodents remains *** this study,Brandt’s vole Lasiopodomys brandtii was exposed to normoxia(21%O_(2))or hypoxia(mild or severe hypoxia:10%or 5%O_(2))for 6 *** in key enzymes of the classic enzymatic antioxidant system at both mRNA and enzyme activity levels,and tissue antioxidant levels of the low-molecular-weight antioxidant system were determined in brain,liver,and *** levels of the upstream regulator NF-E2-related factor 2(Nrf2)were also *** found that the mRNA expression of Nrf2 and its downstream antioxidant enzyme genes in *** were relatively conserved in response to hypoxia in most tissues and genes tested,except in the *** Nrf2,Cu/Zn SOD,GPx1,and GPx3 levels were significantly upregulated in response to mild hypoxia,whereas Mn SOD level decreased significantly in severe *** with changes at the RNA level,constitutively high and relatively stable antioxidant enzyme activities were maintained *** the low-molecular-weight antioxidant system,an abrupt increase of cerebral ascorbic acid(AA)levels in hypoxia indicated a tissue-specific antioxidant *** hypoxia did not cause significant oxidative damage in most tissues tested,the significant decrease in antioxidant enzyme activities(GPX and GR)and increase in lipid peroxidation in the kidney suggest that prolonged hypoxia may pose a critical threat to this species.

关键词： climate change Nrf2 oxidative stress oxygen fluctuation subterranean rodent

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Fine-grained Defect Information Prediction Based Key Factors Identification Method for Strip Steel Manufacturing

Fine-grained Defect Information Prediction Based Key Factors...

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第35届中国过程控制会议

作者： Jinchuan Qian Xuerui Zhang Songyan Pi Zhihuan Song bojian chen Xinmin Zhang State Key Laboratory of Industrial Control Technology College of Control Science and Engineering Zhejiang University

The surface defect is a key factor affecting the quality of steel products, and have attracted great attention in practical strip steel manufacturing. To accurately analyze key factor for improving product quality, this paper proposes a fine-grained defect information prediction based key factors identification method(FDP). The training of the proposed FDP is supervised by fine-gained defect-related information, which is obtained by a designed defect rate calculation strategy. In addition, after combing with data mode clustering, the final identification results are presented by a two-stage explainable method indicated by importance scores.

关键词： Explainable AI Surface Defects Steelmaking Process Key Factors Identification

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以资源基础理论与组织学习理论构建企业之竞争优势

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科技管理研究 2012年第11期32卷 104-109页

作者：陈柏樫吴青桦北京大学经济学院北京100871 高雄应用科技大学国际企业所台湾高雄80778

全球化的趋势加速了产业间竞争的速度,唯有比其它竞争对手更为杰出,才能从中脱颖而出获得胜利。为了创造持续性的竞争优势,企业除了拥有价值性、稀少性、难以模仿且无法替代的资源,还需透过组织内部积极学习及整合的能力,才能更加阻碍... 详细信息

全球化的趋势加速了产业间竞争的速度,唯有比其它竞争对手更为杰出,才能从中脱颖而出获得胜利。为了创造持续性的竞争优势,企业除了拥有价值性、稀少性、难以模仿且无法替代的资源,还需透过组织内部积极学习及整合的能力,才能更加阻碍竞争者的模仿及复制的能力,进而创造出持续性竞争优势。研究主要的目的是从资源基础理论和组织学习的观点来建构企业的竞争优势,并藉企业合作、技术资产、内部人力资本、管理愿景、配置能力和组织学习等要素建立衡量企业绩效的标准。

关键词：资源基础理论组织学习竞争优势多项logit模型

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基于多任务联合模型的居民用电模式分类方法

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电工技术学报 2022年第21期37卷 5490-5502页

作者：徐明杰赵健王小宇宣羿陈伯建上海电力大学电气工程学院上海200090 国网浙江省电力有限公司杭州供电公司杭州310016 国网福建省电力有限公司电力科学研究院福州350000

识别海量居民用户的用电行为模式并进行合理分类,可为需求侧精益化管理提供辅助决策。该文提出一种基于卷积神经网络自动编码器与层次聚类多任务联合模型的居民用电模式分类方法。首先,提出基于同时刻量测数据均值的缺失值填补方法和基... 详细信息

识别海量居民用户的用电行为模式并进行合理分类,可为需求侧精益化管理提供辅助决策。该文提出一种基于卷积神经网络自动编码器与层次聚类多任务联合模型的居民用电模式分类方法。首先,提出基于同时刻量测数据均值的缺失值填补方法和基于季节性极端学生化偏差检验的异常点检测方法,对海量且高维的用电数据进行数据清洗与修正;其次,利用卷积神经网络自动编码器对居民用电数据进行特征提取,获取可表征用户用电行为的特征向量;然后,结合层次聚类算法以及轮廓系数指标确定用户聚类个数以及聚类中心向量,并利用聚类中心向量初始化神经网络聚类层,进行用户聚类,将特征提取过程与用户聚类过程进行联合,组成多任务学习神经网络,实现端到端的用电模式分类;最后,结合环境温度和电价影响因素,在实际数据集进行验证。

关键词：居民负荷负荷聚类卷积神经网络自动编码器联合模型

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中国陆地生态系统净初级生产力时空变化特征及影响因素

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生态学报 2023年第3期43卷 1219-1233页

作者：涂海洋古丽·加帕尔于涛李旭陈柏建中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室乌鲁木齐830011 中国科学院中亚生态与环境研究中心乌鲁木齐830011 中国科学院大学北京100049

为揭示气候变化背景下我国各陆地生态系统净初级生产力(NPP)的时空分布特征与驱动机制,引入重心模型分析2000—2017年我国NPP的空间分布格局变化,并利用相关分析方法结合Thornthwaite Memorial模型定量区分气候变化与人类活动影响NPP的... 详细信息

为揭示气候变化背景下我国各陆地生态系统净初级生产力(NPP)的时空分布特征与驱动机制,引入重心模型分析2000—2017年我国NPP的空间分布格局变化,并利用相关分析方法结合Thornthwaite Memorial模型定量区分气候变化与人类活动影响NPP的相对作用。结果表明:(1)2000—2017年全国NPP均值为325.86 g C/m^(2),整体呈现出南方高北方低,东南向西北逐渐递减的特点。(2)近18年全国与各陆地生态系统NPP均呈现增长趋势,全国NPP增长速率为4.4597 g C m^(-2)a^(-1),总净增加约0.391 Pg C。空间上全国与森林、草地、荒漠生态系统的NPP重心向东北方向移动,农田与城市生态系统的NPP重心向西北方向移动,表明NPP在该方向上的增速和增量最大。(3)全国NPP在华北、西北地区与四川盆地主要受降水的影响,在青藏高原与云贵高原的东部主要受气温的影响,各陆地生态系统之间城市生态系统NPP对降水响应的敏感度相对最高,荒漠生态系统NPP对温度响应的敏感度相对最高。(4)气候变化和人类活动对全国NPP变化的贡献分别约占56%和44%,各陆地生态系统的NPP也表现为受气候变化的影响大于人类活动的影响。此外气候变化对荒漠生态系统NPP的影响最大,对森林生态系统的影响最小,人类活动对各陆地生态系统NPP的影响大小则相反。研究结果可为我国生态环境保护、资源的合理配置以及制定环境、社会经济发展等战略决策提供科学依据。

关键词：陆地生态系统净初级生产力重心模型 Thornthwaite Memorial模型驱动机制

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攀西钒钛磁铁矿尾矿制备储水泡沫陶瓷的研究

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矿产综合利用 2020年第6期41卷 7-13,6页

作者：李林姜涛陈超张裕书周密陈泊键东北大学冶金学院辽宁沈阳110819 中国地质科学院矿产综合利用研究所四川成都610041

以攀西钒钛磁铁矿尾矿和废玻璃为主要原料通过高温烧结法制备储水泡沫陶瓷,研究原料配比和发泡剂(SiC)添加量对材料性能的影响。结果表明,随着钒钛磁铁矿尾矿含量的增加,材料的体积密度及抗压强度逐渐增大,平均气孔孔径逐渐减小;当尾矿... 详细信息

以攀西钒钛磁铁矿尾矿和废玻璃为主要原料通过高温烧结法制备储水泡沫陶瓷,研究原料配比和发泡剂(SiC)添加量对材料性能的影响。结果表明,随着钒钛磁铁矿尾矿含量的增加,材料的体积密度及抗压强度逐渐增大,平均气孔孔径逐渐减小;当尾矿添加量为50%时,材料的体积吸水率出现极值。当SiC添加量为0.3%时,材料内部气孔分布均匀,平均孔径约为2.93 mm。最终以50.0%的钒钛磁铁矿尾矿和50.0%的废玻璃为原料,外加3.0%的石英,0.3%的SiC,3.0%的Na_3PO_4,在1040℃制得性能最优的储水泡沫陶瓷,材料的体积密度为0.26 g/cm^3,体积吸水率为56.5%,抗压强度为0.68 MPa。采用SEM、XRD等检测手段研究材料的微观形貌及物相组成,结果表明储水泡沫陶瓷内部由三维立体结构组成,有利于储存水分;材料主要物相包括硅灰石、长石、透辉石和钛铁矿。

关键词：钒钛磁铁矿尾矿储水泡沫陶瓷配方优化气孔分布

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