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The growth of the screw dislocation of nacreous layer on Pteria penguin

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Science China Earth Sciences 2011年第7期54卷 951-958页

作者： QI LiJian HUANG YiLan zhou ZuYi zhou zhengyu State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

In response to various environmental factors in offshore South China Sea,a group of microstructures of the screw dislocation are assembled in multiphase screw dislocations on the surface of the nacreous layer of Pteria penguin from the coastal waters of Hainan Island,*** results of the transmission and scanning electronic microscope testing show that organic matter periodically secreted by epithelial histology of mantle of Pteria penguin pre-forms the original screw dislocation growth tem-plate in the form of film,along with its function to select,identify,and adhere to the amorphous calcium carbonate particles as the fine organic venations diffused in the epitaxial screw growth *** the inducement and screw modulation of the or-ganic film and venations,the amorphous calcium carbonate particles gradually evolve into the pseudohexagonal *** microsheet with long-range order and screw dislocation structure by location-selecting tropism and screw dislocation *** micron-scale aragonite microsheets join in the cluster's interactive movement and screw dislocation self-assembly of the organic film,stacking forward along the axis C spirally and forming the nacreous layer with screw dislocation structure.

关键词： Pteria penguin nacreous layer organic film aragonite micro sheet screw dislocation

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基于联合层级问答的新闻人物言论抽取方法

中国传媒大学学报（自然科学版） 2024年第3期31卷 57-65页

作者：张能欢冯爽周正宇国家广播电视总局广播电视科学研究院北京100866 中国传媒大学北京100024

新闻人物言论的抽取对理解社会动态、分析公众意见、辅助决策制定至关重要。本文针对新闻场景定义了人物言论事件框架,提出了一种基于联合层级问答的新闻人物言论抽取方法。该方法改变原有的针对起始位置进行预测的指针标注方式和序列标... 详细信息

新闻人物言论的抽取对理解社会动态、分析公众意见、辅助决策制定至关重要。本文针对新闻场景定义了人物言论事件框架,提出了一种基于联合层级问答的新闻人物言论抽取方法。该方法改变原有的针对起始位置进行预测的指针标注方式和序列标注,采用联合层级标注,以提高模型在面对复杂人物名称时的识别能力,并利用多轮问答的特性,准确匹配人物名称和触发词,以解决复杂人物言论抽取中的多任务问题。为进一步提升模型训练效果,引入了额外位置向量和交替双向训练策略。实验结果表明,本文方法在(人物,触发词)抽取、言论抽取以及(人物、触发词、言论)三元组抽取任务中均取得了较好的结果。

关键词：人物言论事件抽取联合层级标注多轮问答

基于RFRM-有限云模型的智能船舶航行风险预警

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中国安全生产科学技术 2024年第1期20卷 172-178页

作者：杨仔豪张英俊邹宜洋周正宇大连海事大学航海学院辽宁大连116026

为了对L3级别智能船舶的远洋航行风险进行预警,提出1种基于RFRM-有限云模型理论的智能船舶航行风险预警模型,全面识别出恶劣气象海况下影响智能船舶远洋航行安全的28个风险指标,对识别出的风险指标进行双重标准过滤和多重标准评估,运用... 详细信息

为了对L3级别智能船舶的远洋航行风险进行预警,提出1种基于RFRM-有限云模型理论的智能船舶航行风险预警模型,全面识别出恶劣气象海况下影响智能船舶远洋航行安全的28个风险指标,对识别出的风险指标进行双重标准过滤和多重标准评估,运用有限云模型理论结合风险指标动态权重对11个关键风险指标进行定量化评级。研究结果表明:采用定性与定量相结合的方式能实现对航行风险的动态预警,研究结果可为船舶航行风险管理提供参考。

关键词：智能船舶航行风险 RFRM 有限云模型动态权重

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甲翠的宝石学和矿物谱学表征研究

激光与光电子学进展 2024年第15期61卷 360-367页

作者：芦明媚刘子琪唐校周征宇陈仪方郑浚豪张灵敏同济大学海洋地质国家重点实验室上海200092 中国美术学院跨媒体艺术系浙江杭州310000 上海宝石及材料工艺工程技术研究中心上海200092 同济大学宝石及工艺材料实验室上海200092

针对岫岩玉中的特色品种——甲翠开展了常规宝石学及谱学分析,以揭示其宝石学及矿物学归属。常规宝石学分析表明,甲翠是一种浅绿色与白色斑纹相间分布的岫岩玉,呈蜡状或油脂光泽,不透明至微透明。测得其折射率均为1.56,密度在2.53~2.67 ... 详细信息

针对岫岩玉中的特色品种——甲翠开展了常规宝石学及谱学分析,以揭示其宝石学及矿物学归属。常规宝石学分析表明,甲翠是一种浅绿色与白色斑纹相间分布的岫岩玉,呈蜡状或油脂光泽,不透明至微透明。测得其折射率均为1.56,密度在2.53~2.67 g/cm^(3)范围内。通过镜下观察、红外光谱实验和激光拉曼光谱实验揭示了甲翠主要由叶蛇纹石组成,次要矿物包含透闪石、方解石和白云石等,其中透闪石相对较为普遍。拉曼光谱与电子探针分析显示,甲翠的绿色部分通常为叶蛇纹石,而白色斑纹处或为透闪石,或为白云石及方解石等碳酸盐矿物。考虑到碳酸盐矿物主要以围岩形式附着,不适合参与玉石命名,因此建议将甲翠限定为一种含透闪石的叶蛇纹石质玉。

关键词：光谱学激光拉曼光谱红外光谱电子探针叶蛇纹石透闪石甲翠岫岩玉

Boosting Zn-ion storage capability of self-standing Zn-doped Co_(3)O_(4)nanowire array as advanced cathodes for high-performance wearable aqueous rechargeable Co//Zn batteries

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Nano Research 2021年第1期14卷 91-99页

作者： Qiulong Li Qichong Zhang zhengyu zhou Wenbin Gong Chenglong Liu Yongbao Feng Guo Hong Yagang Yao College of Materials Science and Engineering Nanjing Tech University30 Puzhu RoadNanjing 211816China National Laboratory of Solid State Microstructuresy College of Engineering and Applied Sciences Jiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Division of Advanced Nanomaterials Key Laboratory of Nanodevices and ApplicationsJoint Key Laboratory of Functional Nanomaterials and DevicesCAS Center for Excellence in NanoscienceSuzhou Institute of Nanotech and NanobionicsChinese Academy of Sciencesy Suzhou 215123China Division of Nanomaterials and Jiangxi Key Lab of Carbonene Materials Suzhou Institute of Nano-Tech and Nano-BionicsNanchangChinese Academy of SciencesNanchang 330200China Department of Chemical and Biomolecular Engineering National University of Singapore4 Engineering Drive 4Singapore 117585Singapore Institute of Applied Physics and Materials Engineering University of Macao.Avenida da UniversidadeTaipaMacao SAR 999078China Department of Physics and Chemistry Faculty of Science and TechnologyUniversity of MacaoAvenida da UniversidadeTaipaMacao SAR 999078China

Neutral aqueous rechargeable Co_(3)O_(4)//Zn batteries with high-output voltage and outstanding cycling stability have yielded new insights into wearable energy-storage *** meet the increasing demand for a means of powering wearable and portable devices,the development of a high-performance fiber-shaped Co//Zn battery would be highly ***,the intrinsically poor conductivity of C 03O4 significantly restricts the application of these high-capacity and high-rate aqueous rechargeable ***,density functional theory(DFT)calculations demonstrate that the substitution of Zn for Co^(3+)leads to an insulatormetal transition in the Zn-doped Co_(3)O_(4)(Zn-Co_(3)O_(4)).In this study,we used metallic Zn-Co_(3)O_(4)nanowire arrays(NWAs)as a novel binder-free cathode to successfully fabricate an all-solid-state fiber-shaped aqueous rechargeable(AFAR)Co//Zn *** resulting fiber-shaped Co//Zn battery takes advantage of the enhanced conductivity,increased capacity,and improved rate capability of Zn-Co_(3)O_(4)NWAs to yield a remarkable capacity of 1.25 mAh·cm^(-2)at a current density of 0.5 mA·cm^(-2),extraordinary rate capability(60.8%capacity retention at a high current density of 20 mA·cm^(-2))and an admirable energy density of 772.6 mWh·cm^(-3).Thus,the successful construction of Zn-Co_(3)O_(4)NWAs provides valuable insights into the design of high-capacity and high-rate cathode materials for aqueous rechargeable high-voltage batteries.

关键词： Zn-doped Co_(3)O_(4) aqueous rechargeable Co//Zn battery fiber-shaped high-capacity high-rate

Characterization and immunogenicity of bone marrow-derived mesenchymal stem cells under osteoporotic conditions

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Science China(Life Sciences) 2020年第3期63卷 429-442页

作者： Yingkang Huang Yin Yin Yanzheng Gu Qiaoli Gu Huilin Yang zhengyu zhou Qin Shi Orthopedic Department the First Affiliated Hospital of Soochow UniversityMedical College of Soochow UniversityOrthopedic Institute of Soochow UniversitySuzhou 215006China Laboratory Animal Center Medical College of Soochow UniversitySoochow UniversitySuzhou 215123China Clinical Immunology Institute of Jiangsu Province the First Affiliated Hospital of Soochow UniversitySuzhou 215006China Key Laboratory of Stem Cells and Biomedical Materials of Jiangsu Province and Chinese Ministry of Science and Technology Suzhou 215123China

Mesenchymal stem cells (MSCs) are characterized by their multilineage potential and low ***,the properties of MSCs under pathological conditions are *** current study investigated the differentiation potential and immunological characteristics of bone marrow-derived MSCs from ovariectomized-osteoporotic rats (OP-BMSCs).Although the expression of cell morphology-and sternness-related surface markers was similar between OP-BMSCs and BMSCs from healthy rats (H-BMSCs),the proliferation rate was significantly decreased compared with that of *** multilineage potential,osteogenesis and chondrogenesis abilities of OP-BMSCs decreased,but the adipogenesis ability was significantly enhanced compared with that of *** expected,decreased osteogenesis following osteogenic induction resulted in reduced expression of p-catenin,osteocalcin,and runt-related transcription factor 2 in ***,the expression of the co-stimulatory proteins CD40 and CD80 was significantly higher,whereas the expression of the negative costimulatory molecule programmed cell death ligand 1 was significantly lower in the OP-BMSCs than that in ***,H-BMSCs inhibited the proliferation and secretion of inflammatory cytokines from anti-CD3 antibody-activated T cells,whereas OP-BMSCs did *** results indicate that decreased osteogenesis and increased immunogenicity of OPBMSCs contribute to bone loss in osteoporosis.

关键词： mesenchymal stem cells osteogenesis chondrogenesis adipogenesis immunogenicity osteoporosis

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聚丙烯腈纤维径向致密结构的光密度法研究

化工新型材料 2024年第3期52卷 109-112页

作者：邓卓寅刘宇涛赵德明周铮钰徐樑华李常清北京化工大学有机无机复合材料国家重点实验室北京100029 北京化工大学碳纤维及功能高分子教育部重点实验室北京100029 威海市产品质量标准计量检验研究院威海264299

凝固过程聚丙烯腈(PAN)初生纤维在径向上各点的双扩散程度不同,可能会造成PAN纤维在径向上致密结构的差异。首先采用光密度法测定PAN初生纤维径向的致密结构及其差异性的可行性和影响因素,在此基础上采用光密度法研究了凝固浴温度对PAN... 详细信息

凝固过程聚丙烯腈(PAN)初生纤维在径向上各点的双扩散程度不同,可能会造成PAN纤维在径向上致密结构的差异。首先采用光密度法测定PAN初生纤维径向的致密结构及其差异性的可行性和影响因素,在此基础上采用光密度法研究了凝固浴温度对PAN初生纤维致密性结构差异的影响。结果表明:对于PAN初生纤维,采用纤维切片厚度为4μm、调整入射光强使背景灰度为140时进行PAN初生纤维光密度的测定;保持凝固浴浓度恒定不变,凝固浴温度从25℃升高到65℃会导致PAN初生纤维的灰度降低、光密度值增大、纤维径向皮部与芯部的光密度差值增大,这表明随着凝固浴温度的升高,纤维的致密性降低、径向致密结构差异增大。光密度法可以用来定量表征PAN纤维的径向结构及其差异。

关键词：聚丙烯腈初生纤维径向结构致密结构光密度凝固浴温度

Cartiex^(TM)Ⅱ型胶原蛋白对大鼠骨关节炎治疗效果研究

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扬州大学学报（农业与生命科学版） 2024年第4期45卷 20-28页

作者：沈艳华潘明明孙菠张乐文胡宇蝶肖敏朱美红周正宇苏州大学苏州医学院实验动物中心江苏苏州215123 嘉兴恒杰生物制药股份有限公司浙江嘉兴314000

为探讨Cartiex^(TM)Ⅱ型胶原蛋白对碘乙酸钠诱导的大鼠骨关节炎(OA)的治疗作用,大鼠膝关节腔内单次注射碘乙酸钠溶液,建立大鼠骨关节炎模型;造模后分别以Ⅱ型胶原蛋白及牛骨胶原蛋白灌胃;试验期间每周测量大鼠饮食、饮水、体重、足底机... 详细信息

为探讨Cartiex^(TM)Ⅱ型胶原蛋白对碘乙酸钠诱导的大鼠骨关节炎(OA)的治疗作用,大鼠膝关节腔内单次注射碘乙酸钠溶液,建立大鼠骨关节炎模型;造模后分别以Ⅱ型胶原蛋白及牛骨胶原蛋白灌胃;试验期间每周测量大鼠饮食、饮水、体重、足底机械痛;试验结束后心脏采血测量血清中前列腺素E2(PGE-2)、转化生长因子β(TGF-β)、金属基质降解酶13(MMP-13)、白介素-1β(IL-1β)、IL-6、肿瘤坏死因子-α(TNF-α)含量;取膝关节甲醛固定、脱钙后进行病理检查。结果表明:造模大鼠膝关节在试验期间出现明显肿胀,各给药组与OA模型组相比均有不同程度缓解。Ⅱ型胶原蛋白高、低剂量组能显著升高大鼠机械痛值,并显著降低血清中MMP-13、IL-1β、IL-6、TNF-α含量,显著升高PGE-2、TGF-β含量。Ⅱ型胶原蛋白干预后,大鼠关节炎症状明显改善,软骨组织增生,炎症细胞浸润明显减少,Mankin’s评分显著降低。综上,Ⅱ型胶原蛋白可调节骨关节炎大鼠血液中相关炎症因子表达,降低关节痛,减少炎症细胞浸润,改善滑膜组织炎症,并促进软骨增生,进而缓解骨关节炎症状;相对于阳性对照品,Cartiex^(TM)Ⅱ型胶原蛋白具有用量少、效果好、起效快的优点。

关键词：大鼠 Ⅱ型胶原蛋白碘乙酸钠骨关节炎

A New Location Precision Model for Multi-Static Over-the-Horizon Radar System

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Wuhan University Journal of Natural Sciences 2010年第2期15卷 143-147页

作者： SONG Jun, ZHAO zhengyu, zhou Chen School of Electronic Information, Wuhan University, Wuhan 430072, Hubei, China School of Electronic Information Wuhan University Wuhan China

In this paper, a multi-static system working in an active way is made up of ionospheric oblique backscatter sounding system （IOBSS） and two separate receiving stations, which adopts discontinuous wave mechanism. We have advanced a new model that contains skywave condition to locate over-the-horizon targets. We use a single quasi-parabolic （QP） ionosphere model and an analytic ray-tracing program to obtain the coordinate registration （CR） index, which changes skywave group range to ground range. Also, IOBSS and other two receiving stations use this distance information to locate the target which is far away from the system. The analytic expression for the geometric dilution of precision （GDOP） under different station deployments are obtained, which shows GDOP is influenced by the system measurement precision, the stations＇ coordinates, and CR index. By computer simulation, we find that GDOP of isosceles right triangle deployment is smaller than that of line deployment and location precision will be improved with increasing base line length. The results indicate that this model is practicable with an acceptable range of error （less than 500 m under certain conditions in this paper）.

关键词： over-the-horizon radar (OTHR) multi-static coor-dinate registration target location