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冷藏凡纳滨对虾肌肉软化的生化特性及生物标记物

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广东海洋大学学报 2024年第1期44卷 125-132页

作者：徐德峰廖威龙李彩虹廖建萌李欣广东海洋大学食品科技学院广东湛江524088 广东医科大学海洋医药研究院广东湛江524023 湛江市食品药品研究所广东湛江524000 桂林理工大学化学与生物学院广西桂林541000

【目的】探究冷藏凡纳滨对虾(Litopenaeus vannamei)质构品质劣变生化变化特性并识别生物标记物。【方法】测定凡纳滨对虾4℃冷藏期间肌肉质构参数,检测肌肉组织中糖原与乳酸含量、ATP水平,以及Ca^(2+)-ATP酶、酸性与碱性磷酸酶(ACP、A... 详细信息

【目的】探究冷藏凡纳滨对虾(Litopenaeus vannamei)质构品质劣变生化变化特性并识别生物标记物。【方法】测定凡纳滨对虾4℃冷藏期间肌肉质构参数,检测肌肉组织中糖原与乳酸含量、ATP水平,以及Ca^(2+)-ATP酶、酸性与碱性磷酸酶(ACP、AKP)活性,分析无氧代谢特征和磷酸化调控酶活性动态变化,解析各指标间相互联系。【结果与结论】4℃冷藏期间对虾质构指标迅速下降,冷藏72 h后硬度显著下降至(2947±113)g(P<0.05),肌原纤维小片化指数(MFI)与质构指标呈显著负相关(P<0.01);新鲜对虾冷藏24 h后磷酸果糖激酶(PFK)活性显著下降至(20.82±0.38)U/mg(P<0.05),且PFK活性与糖酵解各指标相关性最强,其调控的糖酵解是触发和加速肌肉快速软化的关键前期生化事件;ATP含量调控磷酸酶和Ca^(2+)-ATP酶活性,ACP活性和AKP活性在冷藏96 h显著上升至(16.39±1.17)U/mg和(0.86±0.05)U/mg(P<0.05),Ca^(2+)-ATP酶活性24 h后降至(0.50±0.01)U/mg(P<0.05)。随时间延长,Ca^(2+)-ATP酶活性下降诱导内质网释放Ca^(2+)诱导磷酸酶开启去磷酸化进程,蛋白质降解信号暴露被泛素化标记,肌原纤维蛋白进而被降解;相关性分析结合生化基本原理初步判定,Ca^(2+)-ATP酶为质构劣化的生物标记物。

关键词：凡纳滨对虾肌肉软化生化热性生物标记物 Ca^(2+)-ATP酶

中国省际水资源效率与韧性测度及其协同演化分析

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人民珠江 2024年第9期45卷 47-55页

作者：景燕燕郑德凤张茜芮辽宁师范大学地理科学学院辽宁大连116029

水资源效率与韧性是可持续性研究的2个核心问题,分析中国水资源效率与韧性的协同发展关系对促进中国水资源可持续利用具有重要意义。以2000—2022年全国30个省区为研究对象,运用超效率SBM模型和三维矢量模型测度了中国水资源效率和韧性... 详细信息

水资源效率与韧性是可持续性研究的2个核心问题,分析中国水资源效率与韧性的协同发展关系对促进中国水资源可持续利用具有重要意义。以2000—2022年全国30个省区为研究对象,运用超效率SBM模型和三维矢量模型测度了中国水资源效率和韧性水平,并使用哈肯模型探究了两者的协同演化特征。结果表明:研究期内水资源效率呈波动式上升—缓慢下降趋势,2022年中国区域水资源效率均值为0.47,整体上处于非有效区;研究期内中国水资源韧性水平整体呈平稳波动—快速上升—缓慢上升趋势,区域内水资源韧性水平存在梯度差异,表现为东部地区>东北地区>中部地区>西部地区;研究期内中国水资源韧性与效率协同水平整体上呈波动式上升趋势,水资源效率为协同演化的序参量,对整个系统的演化进程起积极导向作用。

关键词：水资源韧性效率协同度

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一种压电换能器热释电防护电路设计

压电与声光 2024年第2期46卷 253-258,263页

作者：李世国潘灿赵德峰母江东李军何知益中国电子科技集团公司第二十六研究所重庆400060 中国电科芯片技术(集团)有限公司重庆401332 云南无线电有限公司云南昆明650223

该文探讨了压电材料热释电效应产生的机理,得出压电换能器中压电陶瓷材料受温度变化会产生极化电荷,引起的热释电压会使压电换能器输出信号幅值增大,导致输出失效。因此针对热释电问题提出了两点解决方案。经过对比分析设计了一种ESD保... 详细信息

该文探讨了压电材料热释电效应产生的机理,得出压电换能器中压电陶瓷材料受温度变化会产生极化电荷,引起的热释电压会使压电换能器输出信号幅值增大,导致输出失效。因此针对热释电问题提出了两点解决方案。经过对比分析设计了一种ESD保护电路来解决热释电问题。该ESD保护电路通过设计一种改进型二极管钳位电路,针对压电换能器存在的极化电荷构建热释电释放环路,消除了热释电压对有用信号收发的影响。最后,通过对比实验验证了设计方案的可行性。

关键词：压电换能器热释电效应信号幅值增大 ESD保护电路改进型二极管钳位电路

基于自适应网格多目标鲸鱼算法的火力分配问题研究

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郑州大学学报（理学版） 2024年第6期56卷 17-24页

作者：佘维王业腾孔德锋刘炜李英豪田钊郑州大学网络空间安全学院河南郑州450002 郑州大学互联网医疗与健康服务河南省协同创新中心河南郑州450052 郑州市区块链与数据智能重点实验室河南郑州450002 军事科学院国防工程研究院工程防护研究所河南洛阳471023

传统多目标优化算法在解决多于两个目标函数的火力分配问题时收敛效果不佳,多样性差,耗时过大。基于此,提出了一种自适应网格多目标鲸鱼优化算法(AG-MOWOA)来解决以震塌比例、弹药成本和自身剩余价值为目标函数的火力分配问题。该算法... 详细信息

传统多目标优化算法在解决多于两个目标函数的火力分配问题时收敛效果不佳,多样性差,耗时过大。基于此,提出了一种自适应网格多目标鲸鱼优化算法(AG-MOWOA)来解决以震塌比例、弹药成本和自身剩余价值为目标函数的火力分配问题。该算法引入混沌映射和外部Pareto存档进化策略提高了种群的多样性,通过自适应网格选取最优个体的方法极大地减少了算法运行时间。仿真实验结果表明,该算法较其他算法收敛速度更快、收敛质量更高、解集分布更多样,能够有效解决火力分配问题。

关键词：火力分配混沌映射自适应网格划分多目标优化鲸鱼优化算法

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A UNIFIED ALGORITHMIC FRAMEWORK OF SYMMETRIC GAUSS-SEIDEL DECOMPOSITION BASED PROXIMAL ADMMS FOR CONVEX COMPOSITE PROGRAMMING

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Journal of Computational Mathematics 2019年第6期37卷 739-757页

作者： Liang Chen defeng Sun Kim-Chuan Toh Ning Zhang College of Mathematics and Econometrics Hunan UniversityChangsha 410082China Department of Applied Mathematics The Hong Kong Polytechnic UniversityHong KongChina Department of Mathematics and Institute of Operations Research and AnalyticsNational University of Singapore10 Lower Kent Ridge RoadSingapore School of Computer Science and Technology Dongguan University of TechnologyDongguanChina

This paper aims to present a fairly accessible generalization of several symmetric Gauss-Seidel decomposition based multi-block proximal alt ernating direction met hods of multipliers(ADMMs)for convex composite optimization *** proposed method unifies and refines many constructive techniques that were separately developed for the computational efficiency of multi-block ADMM-type algor计***,the majorized augmented Lagrangian functions,the indefinite proximal terms,the inexact symmetrie Gauss-Seidel decomposition theorem,the tolerance criteria of approximately solving the subproblems,and the large dual step-lengths,are all incorporated in one algoi?计hmic framework,which we named as *** the popularity of convergent variants of multi-block ADMMs in recent years,especially for high-dimensional multi-block convex composite conic programming problems,the unification presen ted in this paper,as well as the corresponding convergence results,may have the great potential of facilitating the implemen tation of many multi-block ADMMs in various problem set tings.

关键词： Convex optimization Multi-block Alternating direction method of multipliers Symmetric Gauss-Seidel decomposition Majorization

Origin, dissemination and entry of the pandemic Zika viruses

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Science Bulletin 2016年第10期61卷 749-751页

作者： Huimin Zhang Swaminath Srinivas defeng Li Youjun Feng Department of Medical Microbiology and Parasitology Zhejiang University School of Medicine Hangzhou 310058 China Institute for Genomic Biology University of Illinois UrbanaIL 61801 USA Department of Biochemistry University of Illinois UrbanaIL 61801 USA Institute of Biophysics Chinese Academy of SciencesBeijing 100101 China

Zika virus （ZIKV） is a previously-neglected, but newly-emerging zoonotic pathogen that has swept most of the western hemisphere. The unexpected attention aroused worldwide lies in the explosive spread of ZIKV to Brazil and USA in 2015 and its rare correlation to micro- cephaly in newborns, raising a serious challenge to public health. We show the origin and fast dissemination of these epidemic ZIKA isolates. Phylogenetic analyses revealed that all the newly-emerging ZIKV isolates belong to the Asian-American Lineage. Structural analyses of the ZIKV E surface protein suggested that it might adopt a similar entry mechanism to that of other Flavi-viruses like Dengue Virus and West Nile Virus.

关键词： Zika virus Flavivirus DisseminationEntry Origin

播期与播量对河南省秋播饲用燕麦生产性能的影响

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中国饲料 2024年第15期 155-161页

作者：吴嘉浩桑瑞娟董春阳姚晋李德锋河南农业大学动物科技学院河南郑州450046 河南省草地资源创新与利用重点实验室河南郑州450046 河南省牧草工程技术研究中心河南郑州450046

为研究播期与播量对河南省秋播饲用燕麦的影响,试验设置4个播期、3个播种量,研究不同播期与播量对秋播燕麦越冬率、分蘖和株高等农艺性状和干草产量、籽粒产量的影响。结果表明:10月下旬播种的燕麦越冬率最高,早播和晚播燕麦越冬率较低... 详细信息

为研究播期与播量对河南省秋播饲用燕麦的影响,试验设置4个播期、3个播种量,研究不同播期与播量对秋播燕麦越冬率、分蘖和株高等农艺性状和干草产量、籽粒产量的影响。结果表明:10月下旬播种的燕麦越冬率最高,早播和晚播燕麦越冬率较低,但各播期燕麦越冬率均在90%以上;株高、干草和籽粒产量与冬后分蘖数显著正相关;早播燕麦部分分蘖在越冬时被冻死,使其株高、干草和籽粒产量降低;晚播燕麦生育期缩短,分蘖减少,干草和籽粒产量较低;早播和晚播均降低干草产量和籽粒产量,10月下旬播种达到最高,分别为16.10、3.85 t/hm^(2);播种越晚乳熟中期收货时的燕麦草品质越好。综上所述,秋播燕麦可在河南省安全越冬,干草品质、干草和籽粒产量主要受播期影响,播种量对其影响不显著;河南省秋播燕麦适宜在10月下旬播种,播量60~90 kg/hm^(2)。

关键词：燕麦播期播量:生产性能:营养品质

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Morphology control and photocatalytic characterization of WO_3 nanofiber bundles

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Chinese Chemical Letters 2018年第9期29卷 1350-1354页

作者： Ying Zhang defeng Zhang Xinyu Xu Bingsen Zhang College of Chemistry Chemical Engineering and Environmental Engineering Liaoning Shihua University Shenyang National Laboratory for Materials Science Institute of Metal research Chinese Academy of Sciences

The design and fabrication of semiconductor photocatalysts have attracted much attention. Herein, the effect of pH value and soluble salt additives on crystal structure, morphology and photocatalytic properties of WO3 was investigated in detail. It was found that the phase structure of WO3 changed from monoclinic to hexagonal phase when pH value of the solution increased. The ultraviolet-visible absorption spectra show that the monoclinic and hexagonal WO3 had absorbance from 600 nm to the ultraviolet-visible region. Hexagonal WO3 with nanofiber bundle morphology was successfully synthesized through Na2SO4 and Zn（CH3COO）2.2H2O-assisted hydrothermal method when pH value was 0.8. It exhibits the highest photocatalytic efficiency and better than that of cubic-shaped rnonoclinic WO3. The shuttle-like hexagonal WO3 prepared at pH 1.4 gives much lower activity. The morphology is a decisive parameter for the photocatalytic properties of WO3.

关键词： Tungstic trioxide Microstructure Nanofiber bundles Hydrothermal method Photocatalytic activity

Research on cracking mechanism of the thin shell mould in expendable pattern shell casting during pattern removal process

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China Foundry 2010年第3期7卷 230-235页

作者： Jiang Wenming Fan Zitian Liao defeng Zhao Zhong State Key Laboratory of Material Processing and Die ＆ Mould Technology Huazhong University of Science and Technology Wuhan 430074 Hubei China

Aiming at the cracking phenomenon of the thin shell mould in the expendable pattern shell casting during the pattern removing process, some systemic researches are *** influence of the pattern removing method and temperature on the pattern removing were *** shell mould cracking mechanism was analyzed by using thermo-gravimetric analysis (TGA), and combining the temperature field and the volume change of the expanded polystyrene (EPS) foam pattern being *** results indicated that the shell mould was not easily cracked when the pattern removing process was carried out with the furnace being heated little by little because of the shell slowly shrinking with dehydration and shell strength gradually *** shell mould was soon destroyed when it was set directly into the furnace at above 400 oC because of the thin shell mould rapidly shrinking and the foam pattern ***, the shell mould had no cracking when it had been preheated for a long time even if the furnace temperature was above 400 oC and the shell was put into the furnace ***, when the shell mould was directly set into the furnace at lower temperatures, 250 to 300 ℃, the shell would shrink slowly and the foam pattern would stay at the maximum expansion stage temperature of 100 to 110 ℃ for a long time; and the shell mould would experience an expansion force from the foam pattern for a long *** expansion force is related to the pattern removing temperature, holding time, foam pattern thickness and ***, the foam pattern with higher density could make the shell crack.

关键词： expendable pattern shell casting pattern removing cracking shrinkage expansion force