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Nitrous oxide emissions from different land use patterns in a typical karst region, Southwest China

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Chinese Journal Of Geochemistry 2013年第2期32卷 137-145页

作者： CHENG Jianzhong LEE Xinqing zhou zhihong WANG Bing XING Ying CHENG Hongguang State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Fluxes of nitrous oxide (N2O) from different land use patterns (matured forest, secondary forest, grassland and cropland) in a subtropical karst region of Guizhou Province, Southwest China, were measured for one year with a closed static chamber technique and by gas chromatography. The results showed that soil under different land uses was a source of atmospheric N2O. The cropland was a source with relatively high N2O as compared to forest and grassland, but no significant differences were observed. N2O emissions from soils varied with land use change and fertilizer application. There were two peaks of N2O flux occurred following the combination of two obvious precipitation and fertilizer events in the cultivated land. Converting from the matured forest to secondary forest tended to increase annual emissions of N2O (from 1.40 to 1.65 kg N ha -1 a -1 ), while changing land use from secondary forest to scattered grassland tended to decrease annual emissions of N2O slightly (from 1.65 to 1.45 kg N ha -1 a -1 ). Our range of cumulative annual N2O emission across different land uses (1.40-1.91 kg N ha -1 a -1 ) in a karst region is in general agreement with previously published data in a non-karst region. However, in the maize field, N2O emission factor (EF) was 0.34% for fertilizer application, which is about 71.2% lower than the IPCC default value. It is suggested that current IPCC (Intergovernmental Panel on Climate Change) EF methodology could overestimate N2O emission from the karstic cropland. Anyway, the N2O emission from cropland in the karst region would contribute significantly to the global N2O budget, so reducing fertilization frequency during the crop growing season could lead to a decrease in N2O emission in the whole year.

关键词：氧化亚氮排放土地利用方式中国西南地区喀斯特地区 N2O通量 N2O排放森林草原岩溶地区

Multi-field Coupled Inverse Hall–Petch Relations for Ferroelectric Nanocrystals

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Acta Mechanica Solida Sinica 2024年第1期37卷 139-147页

作者： Xiaodong Zhang Wei Yan Xuhui Lou Yujun Chen zhihong zhou Qingyuan Wang Lianhua Ma Xiaobao Tian Non-Destructive Testing Laboratory School of Quality and Technical SupervisionHebei UniversityBaoding 071002China AVIC Huiyang Aviation Propeller Co. LtdBaoding 071051China Department of Mechanics and Engineering Sichuan UniversityChengdu 610065China Yibin Institute of Industrial Technology Sichuan University Yibin ParkYibin 644000China Research Institute of Interdisciplinary Sciences(RISE) Dongguan University of TechnologyDongguan 523808China School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China

Tailoring grain size can improve the strength of polycrystals by regulating the proportion of grains to grain boundaries and the interaction *** the grain size decreases to the nanoscale,the deformation mechanism in polycrystals shifts from being primarily mediated by dislocations to deformation occurring within the grains and grain ***,the mechanism responsible for fine-grain strengthening in ferroelectric materials remains unclear,primarily due to the complex multi-field coupling effect arising from spontaneous *** molecular dynamics simulations,we investigate the strengthening mechanism of barium titanate(BaTiO3),with extremely fine-grain *** material exhibits an inverse Hall–Petch relationship between grain size and strength,rooting in the inhomogeneous concentration of atomic strain and grain ***,we present a theoretical model to predict the transition from the inverse Hall–Petch stage to the Hall–Petch stage based on strength variations with size,which aligns well with the simulation *** has been found that the piezoelectric properties of the BaTiO3 are affected by polarization domain switching at various grain *** study enhances our understanding of the atomic-scale mechanisms that contribute to the performance evolution of fine-grain nano-ferroelectric *** also provides valuable insights into the design of extremely small-scale ferroelectric components.

关键词： Ferroelectrics Multi-field coupling Molecular dynamics Fine-grain reinforcement Inverse Hall-Petch effect

Chemical composition and pharmacological activity of seco-prezizaane-type sesquiterpenes

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Chinese Herbal Medicines 2024年第1期16卷 70-81页

作者： Ye Jin Yanqing Xie Peng Zhang Afsar Khan zhihong zhou Lu Liu Yunnan Yunzhong Institute of Nutrition and Health Yunnan University of Chinese MedicineKunming 650500China Department of Chemistry COMSATS University IslamabadAbbottabad CampusAbbottabad 22060Pakistan

The seco-prezizaane-type sesquiterpenes(SPS),as a special class of sesquiterpenes with a highly oxidative five-ring cage structure and seven consecutive chiral centers,are isolated from the genus Illicium,which have a variety of biological activities,including neurotoxicity and neurotrophic effects,*** review summarizes the chemical constituents and pharmacological effects of SPS,and discusses the potential trend and scope of future research.

关键词： anisatin chemical composition Illicium genus majucin pharmacological activity seco-prezizaane-type sesquiterpenes

Ciphertext-only fault analysis on the Midori lightweight cryptosystem

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Science China(Information Sciences) 2020年第3期63卷 288-292页

作者： Wei LI Linfeng LIAO Dawu GU Shan CAO Yixin WU Jiayao LI zhihong zhou Zheng GUO Ya LIU Zhiqiang LIU School of Computer Science and Technology Donghua University Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Key Laboratory of Integrate Administration Technologies for Information Security School of Microelectronics Shanghai Jiao Tong University Department of Computer Science and Engineering University of Shanghai for Science and Technology

Dear editor,The Midori lightweight cipher can be applied in the RFID tags and other low-resource devices to protect information on the Internet. This cipher was proposed by Banik et al. and presented at the ASIACRYPT conference [1]. It has a Substitution Permutation Network structure with a 128-bit keysize, and two block-size variants, 64 bits

关键词： CFA Ciphertext-only fault analysis on the Midori lightweight cryptosystem

PREPARATION OF TiN FILMS BY N_2 ASSISTED Xe^+ ION BEAM ENHANCED DEPOSITION AND THEIR MECHANICAL PROPERTIES

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Acta Metallurgica Sinica(English Letters) 1992年第11期5卷 370-374页

作者： WANG Xi YANG Genqing LIU Xianghuai ZHENG zhihong HUANG Wei zhou Zuyao ZOU Shichang Ion Beam Laboratory,Shanghai Institute of Metallurgy,Academia Sinica,shanghai,China Shanghai Inst of Metallurgy Acad Sinica Shanghai China

A new method for preparation of hard TiN films has been developed by using electron beam evaporation-deposition of Ti and bombardment with 40 keV Xe^+ ion beam in a N_2 gas *** synthesized TiN films were superior to PVD and CVD ones in respects of improved adhesion to substrate and low preparing *** exhibited good wear resistance and high hardness up to 2200 kg/mm^*** industrial applications have been reported.

关键词： TiN film ion beam enhanced deposition mechanical properties

Research on International Trade VR Practice System Construction Based on Cross-Border E-Commerce

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Research on International Trade VR Practice System Construct...

作者： Zhixia zhou zhihong zhou Yazhou Li Economy and Management College Weifang University Accounting Faculty Shandong Economy and Trade Vocational College

Practical teaching is the core teaching link of applied undergraduate colleges and bears the main task of cultivating applied *** thesis deeply explored the impact of cross-border e-commerce on international trade,constructed practice talent training system based on cross-border e-commerce,based on theoretical analysis and practical research,it proposed comprehensive VR practice platform and operating suggestions for *** research is beneficial for undergraduates to improve their practical abilities in international trade field.

关键词： Practical teaching Cross-border e-commerce VR practice platform International trade

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风力发电机组塔筒地震载荷计算

太阳能学报 2017年第7期38卷 1952-1958页

作者：彭超周志红国电联合动力技术有限公司风电设备及控制技术国家重点实验室北京100039 中联重科股份有限公司长沙410013

建立3种不同精细程度的风力发电机组有限元模型,开展模态分析;采用振型分解反应谱法计算塔底地震载荷。结果表明:考虑叶片的柔性后,塔筒模态频率降低,塔底地震载荷总体上减小;考虑土-结构相互作用后,塔筒模态频率进一步降低,塔底地震载... 详细信息

建立3种不同精细程度的风力发电机组有限元模型,开展模态分析;采用振型分解反应谱法计算塔底地震载荷。结果表明:考虑叶片的柔性后,塔筒模态频率降低,塔底地震载荷总体上减小;考虑土-结构相互作用后,塔筒模态频率进一步降低,塔底地震载荷增大,这是因为塔底地震载荷同时受模态频率和模态振型的影响,模态振型的变化使模态参与因子增大,覆盖了模态频率对地震载荷减小的贡献;塔底地震载荷随地基刚度的变化呈无规律状态,当地基刚度取某个值时,塔底剪切力或弯矩会达到最大值,设计时应予以避免;叶片和土-结构相互作用对塔底地震载荷有重要影响,在建模和计算时应当考虑。

关键词：风力发电机组塔筒地震载荷振型分解反应谱法土-结构相互作用

砥砺奋进六十载，凝心聚力谱新篇——庆祝《华南农业大学学报》创刊60周年

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华南农业大学学报 2019年第5期40卷 226-230页

作者：周志红华南农业大学学报编辑部

《华南农业大学学报》(简称《学报》)是由华南农业大学主管主办的学术期刊,创办于 1959 年 5 月,是 20 世纪 50 年代创(复)办的 70 余种大学自然科学学报之一。2019 年迎来了《学报》创刊 60 周年,60 年来《学报》伴随着学校的发展不断... 详细信息

《华南农业大学学报》(简称《学报》)是由华南农业大学主管主办的学术期刊,创办于 1959 年 5 月,是 20 世纪 50 年代创(复)办的 70 余种大学自然科学学报之一。2019 年迎来了《学报》创刊 60 周年,60 年来《学报》伴随着学校的发展不断成长,经过 8 届编委会和几代编辑人员的努力,《学报》已发展成为在国内有一定影响力的综合性农业科学核心学术期刊,在同类期刊中处于较领先的地位。本文通过查阅《学报》创刊以来的所有期刊以及有关的档案、文献,对《学报》创刊以来的历史进行了梳理,总结经验、肯定成绩,并对《学报》今后的发展进行了展望,为推动《学报》在新时期再上新台阶、跻身我国同类顶级学术期刊之列树立信心。

关键词：大学学报办刊历程经验总结开放办刊回顾与展望

“双一流”建设中高校科技期刊面临的挑战与机遇

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中国科技期刊研究 2021年第1期32卷 41-48页

作者：周志红华南农业大学学报编辑部广东省广州市510642

【目的】了解"双一流"建设对高校科技期刊发展的影响,探讨"双一流"建设给高校科技期刊带来的挑战和机遇。【方法】对137所"双一流"建设高校的中文网站进行搜索,结合电话访问,调查各高校科技期刊的发展状况,从稿源、期刊影响力以及办刊... 详细信息

【目的】了解"双一流"建设对高校科技期刊发展的影响,探讨"双一流"建设给高校科技期刊带来的挑战和机遇。【方法】对137所"双一流"建设高校的中文网站进行搜索,结合电话访问,调查各高校科技期刊的发展状况,从稿源、期刊影响力以及办刊人才等方面分析"双一流"建设高校科技期刊面临的挑战与机遇。【结果】"双一流"建设给高校学科发展带来质的飞跃,产生更多高质量的科研成果,这给高校科技期刊提出更高的要求。高校科技期刊在优质稿源、期刊影响力以及办刊人才等方面普遍存在不足,不能满足高校"双一流"建设的学科发展和学术交流的需要。"双一流"建设促进了高校科技期刊的发展,高校对科技期刊的重视有助于改善办刊环境、吸引优秀人才加入办刊队伍,依托"双一流"的建设,近年来高校科技期刊取得可喜的进步,数量和质量均得到快速的提升。【结论】"双一流"建设对高校科技期刊的发展既是挑战也是机遇,随着高校"双一流"建设的发展和对科技期刊的重视,高校的科技期刊也将迎来一个快速发展期,为我国建设世界一流科技期刊作出应有的贡献。

关键词： “双一流”建设高校科技期刊世界一流期刊挑战与机遇