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Forestry Studies in China 2013年第4期15卷 302-309页

作者： Zhuang WANG yan ZHANG Juan SHI You-qing LUO Li-Li REN Yu-Ming SHI Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry University State Forest Farm in Pinghu

In order to investigate the effect of invastion by pine wood nematode(PWN), this study analyzed several functional indices, i.e., the increment in DBH and stand volume and biomass, in the damaged stands with various mixed percentages of Pinus massoniana and P. thunbergii and with different levels of damage. According to the results of rate of change in increment of DBH and stand volume, the forest ecosystem resistance against PWN increased with a reduction in the mixed ratio of pine. The resistance was highest with a mixed percentage of 50%. The invasion of PWN changed the corresponding relationship of increment between DBH and stand volume(pure stands > 7:3 conifer and broadleaf > 6:4 conifer and broadleaf > 5:5 conifer and broadleaf) among the P. thunbergii stands when there is no damage, but for P. massoniana stands this phenomenon did not occur. For the increment rate of DBH and stand volume, this significant change in P. thunbergii forest indicates that the resistance of pure P. thunbergii forest was higher than that of P. massoniana. The invasion of PWN accelerates the succession from pure stands to mixed stands and then to the broadleaf evergreen stands.

关键词： biological invasion community succession ,plant community function PinuS rnassoniana,PinuS thunbergii

Microstructures and Hardness of 8CrWMoV Steel with Multiple Types of Ultra Fine Carbides

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材料热处理学报 2004年第5期25卷 279-283页

作者： DAIYu-mei ZHANGZhan-ping MAYong-qing QIYu-hong LIUyan-xia YUTao Instituteofmaterialsandtechnology DalianMaritimeUniversityDalian116026

The structure and hardness of 8CrWMoV steel with multiple types of ultra fine carbides are studied after annealing, quenching and tempering in this paper. The results show that multiple types of carbides M3C, M7C3, M23C6, M6C and MC were observed in the annealed steel. Nucleation and coalescence of new carbides, partial dissolution of original carbides in γ phase region during annealing at 800～840℃, result in ultra-fine carbides. Average size of the carbides is0.33～0.34μm in the steel annealed at 800～840℃. Because M3C and M23C6 dissolve easily in austenite, the high hardness HRC63～65 can be obtained by quenching at 840～860℃. Un-dissolved carbides M6C and MC (VC) can effectively prevent the coarsening of austenitic grain, and conduce to obtain very fine martensite. The retained austenite can be easy to decompose during tempering at low and middle temperature due to the precipitation of multiple types of carbides and the good tempering-resistance of the steel is obtained. The microstructure and property of the steel after heat treatment can be accurately explained by calculating based on phase equilibrium *** Words: 8CrWMoV steel, ultra-fine carbide, heat treatment, microstructure,

关键词：显微结构 8CrWMoV钢超细硬质合金硬度热处理

Low thermal expansion and broad band photoluminescence of Zr0.1Al1.9Mo2.9V0.1O12

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Chinese Physics B 2021年第3期30卷 423-429页

作者： Jun-Ping Wang qing-Dong Chen Li-Gang Chen yan-Jun Ji You-Wen Liu Er-Jun Liang Shandong Engineering Research Center of Aeronautical Materials and Devices Key Laboratory of Aeronautical Optoelectronic Materials and DevicesCollege of Aeronautical EngineeringBinzhou UniversityBinzhou 256603China College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Physical Science&Engineering and Key Laboratory of Materials Physics of Ministry of Education Zhengzhou UniversityZhengzhou 450052China

A new material of Zr0.1Al1.9Mo2.9V0.1O12 is synthesized by the traditional solid state synthesis *** phase transition,coefficient of thermal expansion,and luminescence properties of Zr0.1Al1.9Mo2.9V0.1O12 are explored with Raman spectrometer,dilatometer,and x-ray diffraction(XRD)*** results show that the Zr0.1Al1.9Mo2.9V0.1O12 possesses the strong broad-band luminescence characteristics almost in the whole visible *** sample is crystallized in a monoclinic structure group of P21/a(No.14)crystallized at room temperature(RT).The crystal is changed from monoclinic to orthorhombic structure when the temperature increases to 463 *** material has very low thermal expansion performance in a wide temperature *** excellent low thermal expansion and strong pale green light properties in a wide temperature range suggest its potential applications in light-emitting diode(LED)and other optoelectronic devices.

关键词： low thermal expansion phase transition x-ray diffraction(XRD) Raman spectrum luminescence

基于虚拟技术的复合型人才培养体系建设——以化工单元及流程仿真实习为例

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大学化学 2024年第10期39卷 314-317页

作者：熊辉王燕白荣献邬勇奇刘承美龚跃法张建华中科技大学化学与化工学院

针对现有化学化工人才培养体系的不足，基于虚拟仿真技术，本着“虚实结合、相互补充、能实不虚”原则，构建“开放式”和“一站式”的“专业教学–科学研究–就业实践”三层次实验实习实践平台，打造理论知识与实践相结合的虚拟资源，... 详细信息

针对现有化学化工人才培养体系的不足，基于虚拟仿真技术，本着“虚实结合、相互补充、能实不虚”原则，构建“开放式”和“一站式”的“专业教学–科学研究–就业实践”三层次实验实习实践平台，打造理论知识与实践相结合的虚拟资源，提升仿真实习教学效果，提高综合实践能力，培养化学化工复合型应用人才。

关键词：虚拟仿真化工单元生产实习交叉复合培养体系

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2012—2021年河北省营养改善计划地区义务教育阶段学生身高及生长迟缓率变化

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现代预防医学 2024年第2期51卷 250-253+384页

作者：苗润晓罗晓燕赵晶晶周园园田美娜乔晓芳刘长青河北省疾病预防控制中心

目的了解2012—2021年“农村义务教育学生营养改善计划”实施以来，河北省营养改善地区学生身高的变化及生长迟缓状况的变化，为更好的改善学生健康状况以及为下一步决策提供依据。方法采用分层整群的抽样方法对河北省纳入监测的学校... 详细信息

目的了解2012—2021年“农村义务教育学生营养改善计划”实施以来，河北省营养改善地区学生身高的变化及生长迟缓状况的变化，为更好的改善学生健康状况以及为下一步决策提供依据。方法采用分层整群的抽样方法对河北省纳入监测的学校的学生进行体检，测量其身高计算生长迟缓率。结果 2021年同年龄段男生、女生平均身高比2012年平均增长3.62 cm、2.65 cm(P均<0.01)。2012—2021年间男生平均身高增长的峰值在12、13岁，增加值为5.7 cm,女生平均身高增长的峰值在11、12岁，增加值为4.3 cm。男生、女生的生长迟缓率逐年下降(卡方线性趋势检验P均<0.005)。结论 2012—2021年我省农村学生营养改善计划地区6～15岁学生平均身高均增加，但身高平均增速低于全国水平，学生生长迟缓率呈逐年下降趋势，生长迟缓率低于全国平均水平。

关键词：营养改善学生身高生长迟缓

Real-time abnormal light curve detection based on a Gated Recurrent Unit network

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Research in Astronomy and Astrophysics 2020年第1期20卷 49-56页

作者： Rui-qing yan Wei Liu Meng Zhu Yi-Jing Wang Cong Dai Shuo Cao Kang Wu Yu-Chen Liang Xian-Chuan Yu Meng-Fei Zhang College of Information Science and Technology Beijing Normal UniversityBeijing 100875China Department of Astronomy Beijing Normal UniversityBeijing 100875China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

Targeting the problem of high real-time requirements in astronomical data processing,this paper proposes a real-time early warning model for light curves based on a Gated Recurrent Unit(GRU)*** the memory function of the GRU network,a prediction model of the light curve is established,and the model is trained using the collected light curve data,so that the model can predict a star magnitude value for the next moment based on historical star magnitude *** this paper,we calculate the difference between the model prediction value and the actual observation value and set a *** the difference exceeds the set threshold,the observation value at the next moment is considered to be an abnormal value,and a warning is *** can carry out further certification based on the early warning and in combination with other means of *** method proposed in this paper can be applied to real-time observations in time domain astronomy.

关键词： methods:data analysis techniques:photometric stars:variables:general

Knowledge Level about HIV/AIDS among Reproductive Men in Five Counties in China

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Journal of Reproduction and Contraception 2007年第2期18卷 121-126页

作者： Jun-qing WU Bin-yi LIU Wen-ying LI Yu-yan LI Zong-min JIAND Department of Epidemiology and Social Science of Reproductive Health Shanghai hlstitute of Planned Parenthood Research Shanghai 200032 China Fudan University School of Public health Shanghai 200032 China

To understand the HIV/IDS knowledge level and its influential factors among reproductive men in China so as to provide scientific evidence for preventive measures. Methods Cross-sectional survey, system random sample and constructed questionnaire were used in this study. There were 1 285 male subjects who had filled in anon）,mous questionnaires. Results There were significant differences on the HIV/IDS knowledge level in different counties and different demographic characteristic people. Major inJluential factors inchtded area, urban/rural, marriage, educational level, age, consultation about HIV/AIDS. Conclusion It is necessary to strengthen the training of HIV/AIDS knowledge among reproductive men.

关键词： AIDS HIV knowledge reproductive men

Self-template synthesis of peapod-like MnO@N-doped hollow carbon nanotubes as an advanced anode for lithium-ion batteries

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Rare Metals 2023年第3期42卷 929-939页

作者： yan-Ping Liu Chen-Xi Xu Wen-qing Ren Li-Ying Hu Wen-Bin Fu Wei Wang Hong Yin Bin-Hong He Zhao-Hui Hou Liang Chen Key Laboratory of Hunan Province for Advanced Carbon-Based Functional Materials School of Chemistry and Chemical EngineeringHunan Institute of Science and TechnologyYueyang 414006China College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082China School of Materials Science and Engineering Georgia Institute of TechnologyAtlanta 30332USA

The exploration of low-cost and high-performance transition metal oxides/carbon(TMOs/C)-based anodes to replace commercial graphite is still a huge challenge for the development of lithium-ion batteries(LIBs).In this work,MnO@N-doped hollow carbon nanotubes(MnO@NHCNT-v,v refers to the adding volume of pyrrole)hybrids are successfully prepared by a facile selftemplate strategy using Mn3O4 nanotubes(Mn3O4 NT)and pyrrole(PY)as the *** morphology,structure and composition of these MnO@NHCNT-v samples are systematically *** the effect of PY adding amounts on the synthesis of MnO@NHCNT-v samples is also *** results show that the Mn_(3)O_(4) NT works as a self-template,which releases Mn3+and guides the growth of polypyrrole(PPY)on Mn_(3)O_(4) ***,it is demonstrated that the synthesis of MnO@NHCNTv hybrids can be well regulated by the added PY *** a result,MnO@NHCNT-1 hybrid not only makes a good balance on the proportion of MnO and carbon matrix but also simultaneously obtains unique peapod-like structure and successful N doping in NHCNT,resulting in good electrical contact between the two components,enhanced chemical binding by Mn-N-C bonds and enough void space inside its *** from these merits,the resulting MnO@NHCNT-1 hybrid exhibits outstanding cycling stability and rate capability when used as a LIBs *** work offers a good guidance on the design and preparation of low-price and high-performance TMOs/C-based LIBs anodes.

关键词： Self-template strategy Peapod-like structure N doping MnO@N-doped hollow carbon nanotubes(MnO@NHCNT) Lithium storage performance

琼东南盆地中中新统海底扇碎屑岩锆石U-Pb年龄特征及物源分析

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地质科技通报 2024年第5期43卷 45-54页

作者：龚胜利闫琢玉李百强张铜耀吴土荣彭俊峰郑磊张东峰黄向胜罗程飞王任中海油能源发展股份有限公司工程技术分公司天津300450 广东省海上高温高压油气藏勘探开发企业重点实验室广东湛江524057 中国地质大学(武汉)地球科学学院武汉430074 中国地质大学(武汉)地质过程与矿产资源国家重点实验室武汉430074 安徽理工大学地球与环境学院安徽淮南232001

琼东南盆地中中新统海底扇是南海北部天然气勘探的重要目标,但长期以来对该海底扇沉积物的物源并未达成共识,因此,物源分析对于该区天然气勘探有利目标优选具有重要意义。通过钻井取心开展了碎屑锆石U-Pb年龄谱特征研究,并与周缘潜在物... 详细信息

琼东南盆地中中新统海底扇是南海北部天然气勘探的重要目标,但长期以来对该海底扇沉积物的物源并未达成共识,因此,物源分析对于该区天然气勘探有利目标优选具有重要意义。通过钻井取心开展了碎屑锆石U-Pb年龄谱特征研究,并与周缘潜在物源区锆石U-Pb年龄进行了对比分析,示踪了研究区中中新统海底扇物源。结果表明:(1)盆地北部N-1、N-2、N-3、N-4等4口井碎屑锆石U-Pb年龄表现为燕山期(160,157,133,107,102,99 Ma)、印支期(249,241,239 Ma)、加里东期(466,455 Ma)的年龄峰值特征,且与中国海南岛碎屑锆石U-Pb年龄特征相似度高,但与红河、越南中部碎屑锆石U-Pb年龄特征相似度低;(2)盆地南部S-1、S-2、S-3等3口井碎屑锆石U-Pb年龄特征表现为印支期(242,238,237 Ma)、加里东期(435,431,425 Ma)、海西期(396,392 Ma)以及燕山期(143 Ma)的年龄峰值特征,且S-2井具有较年轻的喜马拉雅期(21 Ma)单峰年龄特征。琼东南盆地北部中中新统沉积物源主要来自海南岛,红河及越南中部物源对其影响非常有限,盆地南部中中新统为红河和海南岛双物源供给,且以红河物源为主,自西向东差异明显。

关键词：锆石U-Pb年龄物源海底扇中中新统琼东南盆地碎屑岩

枳壳中3,5,6,7,8,3′,4′-七甲氧基黄酮对湿阻中焦大鼠的改善作用研究

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中国药房 2024年第7期35卷 819-824页

作者：龚文慧谢亚婷辛力严世豪赵蓓蓓郑郁清郭静英商杰郑鹏张金莲江西中医药大学药学院南昌330004

目的研究枳壳中3,5,6,7,8,3′,4′-七甲氧基黄酮(HMF)对湿阻中焦大鼠的改善作用。方法将大鼠随机分为正常组、模型组、阳性对照组(消旋山莨菪碱片,1 mg/kg)和HMF低、中、高剂量组(0.3、0.6、0.9 mg/kg),每组7只。除正常组外,其余各组大... 详细信息

目的研究枳壳中3,5,6,7,8,3′,4′-七甲氧基黄酮(HMF)对湿阻中焦大鼠的改善作用。方法将大鼠随机分为正常组、模型组、阳性对照组(消旋山莨菪碱片,1 mg/kg)和HMF低、中、高剂量组(0.3、0.6、0.9 mg/kg),每组7只。除正常组外,其余各组大鼠均采用内因加外因复合因素法造模。造模成功后,各组大鼠灌胃相应药物或生理盐水,每日1次,连续14 d。观察各组大鼠饮食量、饮水量及精神状态等一般行为学状态,测定大鼠粪便含水率及唾液流率。采用苏木素-伊红染色法观察大鼠胃和小肠组织的病理形态学变化;检测大鼠血浆中醛固酮含量;检测大鼠胃组织中水通道蛋白3(AQP3)表达水平。结果与正常组比较,模型组大鼠饮食量、饮水量均显著减少(P<0.01),粪便含水率、唾液流率、血浆中醛固酮含量和胃组织中AQP3表达水平均显著增加/升高(P<0.01);大鼠胃组织损伤侵及黏膜肌层,黏膜肌层断裂;小肠出现少量肠绒毛糜烂,腺体结构破坏等病理形态学变化。与模型组比较,HMF各剂量组大鼠饮食量、饮水量均增加,粪便含水率、唾液流率、血浆中醛固酮含量和胃组织中AQP3表达水平均减少/降低,上述差异大部分有统计学意义(P<0.05或P<0.01);胃和小肠组织的病理形态学变化均有不同程度改善。结论枳壳燥性成分HMF对湿阻中焦大鼠症状有一定的改善作用,其机制可能与降低血浆醛固酮含量、下调胃组织中AQP3表达有关。

关键词： 3,5,6,7,8,3′,4′-七甲氧基黄酮燥性湿阻中焦醛固酮水通道蛋白