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Biostratigraphic and Chemostratigraphic Correlation for the Base of the Middle Ordovician between Yichang and Western Zhejiang Areas,South China

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 320-329页

作者： ZHANG Yuandong Axel MUNNECKE CHEN Xu cheng junfeng LIU Xiao State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China GeoZentrum Nordbayern FG Palaoumwelt University Erlangen-Nuremberg D-91054 Erlangen Germany Research Institute of Petroleum Exploration and Development East China Company SINOPEC Nanjing 210011 China

The base of the Middle Ordovician （i.e. Dapingian Stage） has been defined at the first appearance datum （FAD） of conodont Baltoniodus？ triangularis at Huanghuachang, Yichang, China,but the precise correlation of the boundary to regions of other facies remain to be resolved. Herein we review the biostratigraphy and chemostratigraphy of the Huanghuachang Global Standard Stratotype-Section and Point （GSSP） section, and present our latest stratigraphic work on the nearby Chenjiahe s ection in Yichang, and the Hengtang Quarry section, Jiangshan, Zhejiang, which is regarded as representative of slope facies. The conodont and graptolite biostratigraphy as well as chemostratigraphy of the Chenjiahe section indicate that the base of the Middle Ordovician also falls within the graptolite Azygograptus suecicus Zone, and coincides with a high or maximum δ13C value within a minor positive carbon isotope excursion, suggesting that the base boundary can be readily recognized across the entire Yangtze Gorges area. The integrated graptolite and conodont biostratigraphy and chemostratigraphy of the Hengtang section, Jiangshan, indicates that the basal boundary probably falls within the graptolite lsograptus caduceus imitatus Zone that overlies the Azygograptus suecicus Zone, and coincides with a remarkable drop of δ13C. This difference indicates that a multi-disciplinary approach is critical to identify the base boundary in those regions where the Baltoniodus ？ triangularis is absent.

关键词： Graptolite biostratigraphy chemostratigraphy Middle Ordovician slope facies South China

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铝氢化钠储氢性能及其改进方法研究进展

科技导报 2024年第4期42卷 84-90页

作者：仝小刚李志鹏程军锋陇南师范高等专科学校陇南742500

配位氢化物NaAlH_(4)具有较高的储氢密度且生产成本低廉,是一种典型的储氢材料;然而,较高的脱氢温度、较慢的氢吸放速率及较差的可逆性限制了其实际应用。作为一种很有前途的车载储氢介质,其储氢性能的改性研究长期备受关注。论述了NaAl... 详细信息

配位氢化物NaAlH_(4)具有较高的储氢密度且生产成本低廉,是一种典型的储氢材料;然而,较高的脱氢温度、较慢的氢吸放速率及较差的可逆性限制了其实际应用。作为一种很有前途的车载储氢介质,其储氢性能的改性研究长期备受关注。论述了NaAlH_(4)储氢性能及其改进方法,阐明了添加催化剂和结构纳米化2种基本改进方法的原理,也阐述了理论模拟在研究NaAlH4储氢性能中的重要促进作用。

关键词： NaAlH_(4) 化学储氢储氢性能催化剂结构纳米化

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集中配筋连接预制剪力墙抗震性能试验研究

中南大学学报（自然科学版） 2024年第1期55卷 201-218页

作者：肖扬卢谦罗小勇陈林松程俊峰张璧玮中南大学土木工程学院湖南长沙410075 湖南省装配式建筑工程技术研究中心湖南长沙410075 中交第二航务工程局有限公司技术中心湖北武汉430014

针对现有预制混凝土剪力墙接缝施工容错率低、混凝土现场浇筑作业量大和钢筋锚固过长等不足,提出一种使用超高性能混凝土(UHPC)的集中配筋连接预制剪力墙。通过对比1片现浇剪力墙试件、3片不同接缝形式的集中配筋连接预制剪力墙试件的... 详细信息

针对现有预制混凝土剪力墙接缝施工容错率低、混凝土现场浇筑作业量大和钢筋锚固过长等不足,提出一种使用超高性能混凝土(UHPC)的集中配筋连接预制剪力墙。通过对比1片现浇剪力墙试件、3片不同接缝形式的集中配筋连接预制剪力墙试件的拟静力试验结果,揭示该类预制剪力墙的破坏规律和抗震性能、竖缝对墙体抗震性能的影响和连接钢筋的受力特点。采用ABAQUS软件对试件进行有限元模拟,分析轴压比和集中配筋率对试件抗震性能的影响。研究结果表明:预制试件与现浇试件具有相同的破坏规律,均为弯剪破坏;这2类试件的滞回曲线均较饱满,骨架曲线走势基本一致,耗能能力接近,且预制试件的最小承载力仅比现浇试件低5.6%,表明预制试件的抗震性能与现浇试件的抗震性能基本相同;竖缝对剪力墙承载力的影响较小,使剪力墙的延性和耗能能力有一定的削弱;不同竖缝形式预制墙的抗震性能相近但各有特点,竖缝形式预制墙采用UHPC出筋搭接具有更好的整体性,采用U形键槽的预制墙具有更大的刚度和更强的耗能能力;连接钢筋的应力分布具有典型受弯构件的特征;随着轴压比增加,模型的刚度和承载力不断增加,在轴压比从0.05增加到0.30时,最大的峰值荷载增幅发生在轴压比从0.05到0.10时,从承载力的提高、刚度、耗能和墙角抬高等方面考虑,试件的集中配筋率保持在90%~110%为宜。

关键词：预制剪力墙集中配筋拟静力试验 UHPC(ultra-high performance concrete) 抗震性能

聚丙烯酰胺/羧甲基壳聚糖/羟基化氮化硼复合水凝胶的制备以及导热传感性能

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功能高分子学报 2024年第2期37卷 130-137页

作者：刘浩辰柯桂嫔黄蓓曹峥成骏峰陶国良刘春林常州大学材料科学与工程学院材料科学与工程国家级实验教学示范中心江苏常州213164 常州大学怀德学院江苏靖江214500

利用丙烯酰胺(AM)和羧甲基壳聚糖(CMCS)构建双网络结构,采用浸泡六水合三氯化铁(FeCl_(3)·6H_(2)O)溶液的策略,并引入羟基化氮化硼(OH-BNNS),通过两步法制备出复合水凝胶(PAM/CMCS-Fe^(3+)/OH-BNNS)。通过扫描电子显微镜和傅里叶变换... 详细信息

利用丙烯酰胺(AM)和羧甲基壳聚糖(CMCS)构建双网络结构,采用浸泡六水合三氯化铁(FeCl_(3)·6H_(2)O)溶液的策略,并引入羟基化氮化硼(OH-BNNS),通过两步法制备出复合水凝胶(PAM/CMCS-Fe^(3+)/OH-BNNS)。通过扫描电子显微镜和傅里叶变换红外光谱仪对水凝胶进行了结构表征,并通过电子万能材料试验机对其进行了力学性能以及自回复性能的测试,最后还通过导热系数测试仪以及热红外成像仪对其导热性能进行了测试。研究表明,该水凝胶具有超柔韧性、良好的导热性、吸水性、优异的机械强度和自回复性能。OH-BNNS的引入使复合水凝胶在力学和热响应中都表现出明显的增强,其导热系数最大能达到0.514 W/(m·℃)。

关键词：羧甲基壳聚糖羟基化氮化硼聚丙烯酰胺热响应机械增强

Suppression of Dilepton in Expanding Hot Baryon-Rich Quark-Gluon Matter

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Chinese Physics Letters 1994年第8期11卷 472-475页

作者： HE Zejun ZHANG Jiaju cheng junfeng XIU Xaoming Institute of Nuclear Research Academia SinicaShanghai 201800 CCAST(World Laboratory) P.O.Box 8730Beijing 100080 Department of Applied Physics Shanghai Jiaotong UniversityShanghai 200030

With the increase of the initial baryon density,the dilepton production in invariant masses between 2mπ and 1 GeV is shown to be suppressed and an abnormal peak of the dilepton spectrum appears near the invariant mass 0.75 GeV if a baryon-rich quark-gluon matter was formed in the ultrarelativistic nucleus-nucleus collision.These predictions are important for several large-scale experiments at CERN and Brookhaven.

关键词： invariant lepton quark

Satellite E2E Network Slicing Based on 5G Technology

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ZTE Communications 2020年第4期18卷 26-33页

作者： ZHANG Jing WEI Xiao cheng junfeng FENG Xu China Academy of Electronics and Information Technology Beijing 100041China

We investigate the design of satellite network slicing for the first time to provide customized services for the diversified applications,and propose a novel scheme for satellite end-to-end(E2E) network slicing based on 5G technology,which provides a view of common satellite network slicing and supports flexible network deployment between the satellite and the ground.Specifically,considering the limited satellite network resource and the characteristics of the satellite channel,we propose a novel satellite E2E network slicing architecture.Therein,the deployment of the network functions between the satellite and the ground is coordinately considered.Subsequently,the classification and the isolation technologies of satellite network sub-slices are proposed adaptively based on 5G technology to support resource allocation on demand.Then,we develop the management technologies for the satellite E2E network slicing including slicing key performance indicator(KPI) design,slicing deployment,and slicing management.Finally,the analysis of the challenges and future work shows the potential research in the future.

关键词： satellite communications E2E network slicing diversified applications 5G technology

乙肝相关肝细胞癌患者外周血T细胞表面PD-1分子的表达及临床意义

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肝胆胰外科杂志 2024年第5期36卷 306-309页

作者：程俊峰厉学民任超吴晓康傅俊豪浙江大学医学院附属金华医院肝胆胰外科一区浙江金华321000 浙江大学医学院附属金华医院中心实验室浙江金华321000

目的探讨乙肝相关肝细胞肝癌(HCC)患者外周血T细胞表面程序性死亡受体1(PD-1)分子的表达及临床意义。方法收集2021年6月至2022年7月浙江大学医学院附属金华医院肝胆胰外科收治的乙肝相关HCC手术患者共50例(肝癌组),并选择性别、年龄匹配... 详细信息

目的探讨乙肝相关肝细胞肝癌(HCC)患者外周血T细胞表面程序性死亡受体1(PD-1)分子的表达及临床意义。方法收集2021年6月至2022年7月浙江大学医学院附属金华医院肝胆胰外科收治的乙肝相关HCC手术患者共50例(肝癌组),并选择性别、年龄匹配的30单纯慢性乙肝患者作为对照组。采用流式细胞学方法检测两组患者外周血CD4^(+)T细胞、CD8^(+)T细胞表面PD-1分子的表达率并比较两组PD-1表达的差异,并分析其与临床病理参数的关系。结果乙肝相关HCC患者外周血CD4^(+)T细胞、CD8^(+)T细胞表面PD-1分子表达率高于单纯慢性乙肝患者[(14.28±7.73)%vs(11.95±4.0)%,(18.22±8.21)%vs(13.04±4.85)%,均P0.05);在术前AFP>400 ng/mL,中性粒细胞与淋巴细胞比值(NLR)≥2.81,肿瘤最大径≥5 cm,存在微血管浸润的患者中PD-1分子表达率更高(均P<0.05);且肿瘤分化程度越低,肿瘤中国肝癌分期(CNLC)越靠后,PD-1分子表达率越高。结论外周血T细胞表面PD-1分子表达可能参与乙肝相关HCC的发生、发展,并与肝癌患者的临床病理特征具有相关性。

关键词：程序性死亡受体1(PD-1) 肝细胞癌慢性乙型肝炎外周血 T细胞中性粒细胞/淋巴细胞比值

Ordovician graptolite-bearing strata in southern Jiangxi with a special reference to the Kwangsian Orogeny

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Science China Earth Sciences 2010年第11期53卷 1602-1610页

作者： Xu Chen YuanDong Zhang JunXuan Fan junfeng cheng QiJian Li Chinese Acad Sci Nanjing Inst Geol & Palaeontol State Key Lab Palaeobiol & Stratig Nanjing 210008 Peoples R China

The Ordovician graptolite sequence of the Yongxin-Chongyi area in southern Jiangxi was suggested as a standard for the correlation of Ordovician in the Zhujiang region of South China. Based on a restudy of the Upper Ordovician graptolites, the Shikou and Huamianlong formations are recognized herein as a part of the Hanjiang Formation, corresponding only to the Dipla-canthograptus caudatus-Diplacanthograptus spiniferus Zone. Two graptolite zones in the Longxi Formation of Yongxin and Chongyi, the Nemagraptus gracilis Zone and Climacograptus bicornis Zone, are redefined here. A rapid replacement of facies from the typical deep-water graptolitic black shale of Longxi Formation to the rapidly-accumulated, shallow-water clastic deposits of Hanjiang Formation indicates the tectonic initiation of the Kwangsian Orogeny. The thick clastic deposits of the Han-jiang Formation are proposed to come from a nearby source area that rose during the Kwangsian Orogeny. The D. caudatus-D. spiniferus graptolite Zone of the Hanjiang Formation indicates the initiation time of this tectonic event.

关键词： Longxi Formation Hanjiang Formation Sandbian Ordovician graptolite Kwangsian Orogeny

Exploration of the mechanism of cavitation vortex rope and vortex development in the draft tube of tubular turbine units

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 163-171,F0002页

作者： Chuang cheng Zhenggui Li Changrong Shen Shenglong Gu Chuchu Zeng Chuanzheng Bai Meng Liu junfeng Hu Qinghai University of Science and Technology Xining 810000China Key Laboratory of Fluid and Power Machinery Ministry of Education(Xihua University)Chengdu 610039China South-to-North Water Diversion East Jiangsu Water Source Co. Ltd.Nanjing 210029China School of civil engineering and water resources Qinghai UniversityXining 810016China Dongyuan Branch of Shenzhen Water Planning and Design Institute Co. Ltd.Changsha 410000China

Draft tube vortex rope is considered a special cavitation flow phenomenon in tubular turbine units.Cavitation vortex rope is one of the most detrimental factors affecting the safety of hydraulic turbines.In this study,ANSYS CFX software was utilized to numerically simulate the internal cavitation flow of a hydraulic turbine draft tube.The evolution of the cavitation vortex core was characterized by vortex line distribution and vorticity transport equation.The shape and number of blades influenced the revolving direction and distribution characteristics of the vortex close to the runner cone,which formed a counterclockwise-clockwise-counterclockwise distribution pattern.Simultaneously,there were many secondary flows in the draft tube.Mutual cancellation and dissipation between the flows was one of the reasons for reduction in vorticity.When the cross-sectional shape of the draft tube was changed,the vorticity was distributed from the center of the vortex rope to all parts of the cross-sectional draft tube,with extreme values at the center and at the walls.The vortex stretching and dilatation terms played a major role in the change in vorticity,with the baroclinic torque having an effect at the center of the vortex rope,this study is helpful to understand the flow of water in the draft tube and guide the design and optimization of the draft tube in engineering application.

关键词： cavitation vortex rope vorticity transport equation vortex line draft tube