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In situ measured growth rates of bainite plates in an Fe-C-Mn-Si superbainitic steel

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International Journal of Minerals,Metallurgy and Materials 2014年第4期21卷 371-378页

作者： Zhang-wei hu guang Xu Hai-jiang hu Li Wang Zheng-liang Xue Key Laboratory for Ferrous Metallurgy and Resources Utilization of the Ministry of Education Wuhan University of Science and Technology State Key Laboratory of Development and Application Technology of Automotive Steels (Baosteel Group)

The growth rates of bainite plates in an Fe-C-Mn-Si superbainitie steel were investigated by in situ observation. The lengthening rates of ferrite bainite during both cooling and isothermal holding processes were observed and the growth rates of bainite plates nucleating at grain boundaries, within grains and on preformed bainite were measured. It is indicated that the lengthening rates of bainite plates during the cooling and isothermal processes were different, and that the growth rates of bainite plates nucleating at different types of sites also demon- strated diversity. The bainite plates initiating at [vain boundaries during cooling grew the fastest, while the plates nucleating on preformed bainite did the slowest. However, the growth rate of the bainite plates nucleating at grain boundaries during isothermal transformation de- creased the most, whereas the bainite plates initiating within grains grew the fastest. In addition, the growth rate of ferrite bainite in the study supported the diffusion transformation mechanism of bainite from the viewooint of ~rowth rate.

关键词： bainitic steel bainite growth rate cooling isothermal treatment phase transitions

Two pairs of chlorine-containing phenylpropanoid enantiomers from Acorus tatarinowii

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Chinese Chemical Letters 2017年第7期28卷 1460-1464页

作者： yuan-yuan Lu Xue-Peng Gong Yong-Bo Xue hu-Cheng Zhu Xiao-Nian Li Lin-Zhen hu Jian-Kun Guan Jin-Wen Zhang guang Du Yong-hui Zhang Tongji Hospital Affiliated to Tongji Medical College Huazhong University of Science and Technology hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of Pharmacy Tongji Medical College Huazhong University of Science and Technology State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences College of Life Science Hubei University

Two pairs of chlorine-containing phenylpropanoid enantiomers（1a/1b and 2a/2b） were isolated from the rhizomes of Acorus tatarinowii. Interestingly, these optical isomers（1a/1b and 2a/2b） were co-existed in the same plant, which were characterized as the first halogen-containing natural products from the genus Acorus. Their structures and absolute configurations were elucidated by a combination of spectroscopic analysis and a single-crystal X-ray diffraction, assisted by a modified Mosher＇s method. The phenylpropanoid isomers（1a/1b and 2a/2b） were evaluated for their antioxidant activities using DPPH assay and cytotoxic activities against five human cancer cell lines.

关键词： Acorus tatarinowii Chlorine-containing phenylpropanoid Enantiomers Antioxidant activity Cytotoxicity

Buckling of composite cylindrical shells with ovality and thickness variation subjected to hydrostatic pressure

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Defence Technology（防务技术） 2022年第5期18卷 862-875页

作者： Zhun Li Ke-chun Shen Xin-hu Zhang guang Pan School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an710072China Key Laboratory for Unmanned Underwater Vehicle Northwestern Polytechnical UniversityXi'an710072China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China

The initial geometric imperfection is one of the primary factors affecting the buckling behaviors of composite cylindrical shells under hydrostatic *** this study,ovality and thickness variations as two representative types of the geometric imperfections are *** measuring the geometric imperfections,a typical carbon fiber reinforced polymers(CFRP)cylindrical shell is tested to obtain the buckling *** buckling behaviors of the shell sample are analyzed in combination with the strain *** using the nonlinear numerical analysis,the buckling shapes of the CFRP cylinder shells with different combinations of ovality and thickness variation are firstly *** rules of influence of such imperfections on the buckling pressure are then obtained by nonlinear regression ***,an empirical formula is proposed to predict the buckling pressure of the composite cylinder shells,and the calculated results from the formula are in good agreement with the numerical results.

关键词： Composite Cylindrical shell Buckling Hydrostatic pressure Imperfections

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方钢管混凝土柱穿入式组合节点耗能机制

Evaluation of differential antitermitic activities of Lantana camara oven-dried tissues against Reticulitermes virginicus （Isoptera： Rhinotermitidae）

工程力学 2025年第1期42卷 116-128页

作者：徐庆元雷建雄丁发兴周期石张华帅邱远光杨建军中南大学土木工程学院湖南长沙410075 中铁城建集团有限公司湖南长沙410075 中铁城建第一工程有限公司湖南长沙410075

开展了4个翼缘削弱的钢管混凝土柱穿入式组合节点抗震性能与三维实体有限元精细化模型分析。在混凝土三轴塑性损伤和钢材混合强化模型基础上，进一步引入钢材的韧性损伤模型，探讨了钢梁削弱程度对节点抗震性能与破坏形式的影响规律，... 详细信息

开展了4个翼缘削弱的钢管混凝土柱穿入式组合节点抗震性能与三维实体有限元精细化模型分析。在混凝土三轴塑性损伤和钢材混合强化模型基础上，进一步引入钢材的韧性损伤模型，探讨了钢梁削弱程度对节点抗震性能与破坏形式的影响规律，结果显示引入钢材韧性损伤的有限元模型分析结果与试验结果更加吻合，且钢梁削弱程度降低了该节点的刚度、承载力和耗能。随后对不同钢梁尺寸和柱端拉筋强构造下的组合节点进行了承载力、刚度和塑性耗能分配与失效机制的影响规律分析，分析结果表明：穿入式节点分别在梁-柱抗弯承载力比介于1.66~2.11、梁-柱线刚度比介于1.90~1.96、梁-柱截面刚度比介于1.16~1.21时，将由梁耗能向柱耗能转变;柱端拉筋强构造技术后，由于拉筋直接约束混凝土，大幅度提升了柱端抗弯承载力和耗能能力，组合节点在高轴压比时仍维持梁端失效破坏模式;根据《建筑抗震设计规范》，梁-柱抗弯承载力比取值小于1时为强柱弱梁，这对穿入式组合节点强柱弱梁的定义较为保守。

关键词：方钢管混凝土柱钢-混凝土组合梁穿入式组合节点韧性损伤塑性耗能

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Insect Science 2011年第6期18卷 671-681页

作者： Zhonglin yuan Xing Ping hu Qingdao Agricultural University Qingdao Shandong Province China Department of Entomology and Plant Pathology Auburn University Auburn Alabama USA

Chemical-treated soil or physical barriers have been the most commonly used approach for termite management. We hypothesized that a barrier of soil incorporated with oven-dried Lantana camara L. tissues could prevent termite infestation. We first examined the antitermitic effects of the dried tissues from two cultivars （＇Mozelle＇ and ＇New Gold＇） on the subterranean termite, Reticulitermes virginicus （Banks）（Isoptera： Rhinotermitidae）. Results show that all of the tissues of Mozelle had greater antitermic activity than corresponding tissues of New Gold, and leaves had greater termiticidal effects than flowers and stems. When termites were exposed to the test materials in a no-choice bioassay, the 24-day test resulted in a significant reduction of survival （52.5%-88.6%）, running speed （18.2%-37.3%）, live weight （21.8%-53.5%） and body water content （33.2%-56.2%） compared to the control. The consumption of leaves and flowers was exiguous. When used as 25% tissue mulch-barrier, the oven-dried lantana tissues decreased termite tunneling and wood consumption and increased termite mortality. The decreased survival, vigor, and low consumption indicate a toxic and anti-feeding property of the materials tested. The results therefore support our hypothesis that the dried lantana tissues possess antitermitic activities.

关键词： antitermitic activity mulch barrier bioassay no-choice bioassay organictermite control oven-dried plant tissues subterranean termite termiticidal toxicity

The distribution, hydrocarbon potential, and development of the Lower Cretaceous black shales in coastal southeastern China

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Journal of Palaeogeography 2017年第4期6卷 333-351页

作者： guang hu Wen-Xuan hu Jian Cao Ruo-Fei Yang Hong-Yu Chen Dong-Fang Zhao Qian Pang Hong-yuan Wang Xiu-Cheng Tan State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation School of Geoscience and Technology Southwest Petroleum University School of Geoscience and Technology Southwest Petroleum University Petro China Key Laboratory of Carbonate Reservoir Southwest Petroleum University State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing University

Lower Cretaceous black shales in coastal southeastern China are of significance to the geological study of the Tethys and Pacific realms and to hydrocarbon exploration of southeastern China and East China Sea. However, the stratigraphic correlation, distribution patterns and hydrocarbon potential of the black shales have not been well constrained so far. In this study, the zircon UePb ages, organic petrologic and geochemical analyses were performed for representative outcrop sections in the region. Zircon UePb ages demonstrate that the Lower Cretaceous black shales in coastal southeastern China can be divided into two regional-scale sets. The first set was deposited during the early stage of the Early Cretaceous（K_1~1, BerriasianeHauterivian）. The second set was deposited during the late stage of the Early Cretaceous（K_1~2）, and might extend to the Taiwan Strait. Detailed organic geochemical analyses including organic matter abundance, type and maturity of the Lower Cretaceous black shales demonstrate that the organic matter abundance of the sources reached medium to good quality by the hydrocarbon source rock standards, and the average TOC values and the chloroform bitumen ＂A＂ of the K_1~1 black shales are higher. The type of organic matter is mainly type III, type II can also be found from the K_1~2 black shales. The thermal maturity of most samples is high to overmature. A relatively comprehensive hydrocarbon resource evaluation indicates that favorable regions are in the northern guangdong Province for the K_1~1 and in the coastal region of Zhejiang Province and the westernFujian Province for the K_1~2. Sedimentology studies on the Shipu section for the K_1~1 black shales illuminated that the K_1~2 black shales in coastal southeastern China were mainly deposited during transgressive period. The relative sea level changes controlled the sequential development pattern of the K_1~2 black shales.

关键词： Lower cretaceous Black shales Hydrocarbon potential Development pattern Southeastern China

Packet Cache-Forward Method Based on Improved Bayesian Outlier Detection for Mobile Handover in Satellite Networks

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China Communications 2016年第6期13卷 167-177页

作者： Hefei hu Dongming yuan Mingxia Liao yuan'an Liu School of Information and Communication Engineering Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications

In this paper, we propose a Packet Cache-Forward(PCF) method based on improved Bayesian outlier detection to eliminate out-of-order packets caused by transmission path drastically degradation during handover events in the moving satellite networks, for improving the performance of TCP. The proposed method uses an access node satellite to cache all received packets in a short time when handover occurs and forward them out in order. To calculate the cache time accurately, this paper establishes the Bayesian based mixture model for detecting delay outliers of the entire handover scheme. In view of the outliers' misjudgment, an updated classification threshold and the sliding window has been suggested to correct category collections and model parameters for the purpose of quickly identifying exact compensation delay in the varied network load statuses. Simulation shows that, comparing to average processing delay detection method, the average accuracy rate was scaled up by about 4.0%, and there is about 5.5% cut in error rate in the meantime. It also behaves well even though testing with big dataset. Benefiting from the advantage of the proposed scheme in terms of performance, comparing to conventional independent handover and network controlled synchronizedhandover in simulated LEO satellite networks, the proposed independent handover with PCF eliminates packet out-of-order issue to get better improvement on congestion window. Eventually the average delay decreases more than 70% and TCP performance has improved more than 300%.

关键词： satellite networks handover bayesian method outlier detection

Current status and challenges of pig-to-human organ xenotransplantation

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Science China(Life Sciences) 2024年第4期67卷 829-831页

作者： Minghui Fang Yong-guang Yang Zheng hu Key Laboratory of Organ Regeneration&Transplantation of Ministry of Education and National-Local Joint Engineering Laboratory of Animal Models for Human DiseasesThe First Hospital of Jilin UniversityChangchun 130061China

Organ shortage is a global *** collected by the Global Observatory on Donation and Transplantation reveals that over 150,000 solid organ transplants are conducted globally each year,a 52%increase from 2010(http://***/... 详细信息

关键词： globally global shortage

Longitudinal Susceptibility of S=1/2 Low-Dimensional Heisenberg Ferromagnet in a Magnetic Field

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Communications in Theoretical Physics 2008年第5期49卷 1349-1352页

作者： CHEN yuan XIANG Ying hu Ai-yuan Department of Physics Guangzhou University Guangzhou 510006 China School of Information Engineering Guangdong University of Technology Guangzhou 510006 China

Longitudinal susceptibifity of the spin-1/2 low-dimensional Heisenberg ferromagnet in a magnetic field, is studied by the Green＇s function method within the random phase approximation. The static and dynamic longitudinal susceptibilities are calculated in the low- and high-field regions. Power laws for the position and height of the static susceptibility maximum are shown not to support the predictions of Landau theory.

关键词： Heisenberg ferromagnet longitudinal susceptibility Green's function