检索结果-南通市图书馆

Science China Earth Sciences 2009年第12期52卷 1932-1952页

作者： VIJAYA Birbal Sahni Institute of Palaeobotany 53 University Road Lucknow 226007 India

The study of Upper Paleozoic and Mesozoic palynomorphs in three boreholes from the Deocha-Pachami area, Birbhum Coalfield, West Bengal, India, has allowed dating of the Talchir, Barakar, Dubrajpur, and Rajmahal formations, and revealed many hiatuses. The lowermost unit, the Talchir Formation, yielded earliest Permian palynomorphs. The Barakar Formation, which includes coal-bearing strata, was previously dated as Early Permian. However, data presented herein indicate an Early Permian to earliest Triassic age for this unit,containing actually the Karharbari, Barakar s.s., Kulti, and Ranigang formations as well as the basal part of the Panchet Formation. The overlying Dubrajpur Formation is Jurassic (Callovian to Tithonian), with an unconformity at its base. The uppermost Dubrajpur Formation is Tithonian-Berriasian. The palynomorphs from the intertrappeans within the Rajmahal Formation suggest an Early Cretaceous age. The revised ages of the Barakar and Dubrajpur formations are of major regional significance. The distribution patterns of spore-pollen may provide a broad spectrum of paleoclimate during Permian, Late Jurassic, and Early Cretaceous times, as there is no record of marine signatures in the study area.

关键词： Talchir to Rajmahal formations Upper Paleozoic Mesozoic spores and pollen biostratigraphy India

Vanishing Results for the Cotton Tensor on Gradient Quasi-Einstein Solitons

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2021年第4期37卷 588-596页

作者： Lin Feng WANG School of Science Nantong UniversityNantong 226007P.R.China

In this paper we study on gradient quasi-Einstein solitons with a fourth-order vanishing condition on the Weyl *** precisely,we show that for n≥4,the Cotton tensor of any ndimensional gradient quasi-Einstein soliton with fourth order f-divergence free Weyl tensor is flat,if the manifold is compact,or noncompact but the potential function satisfies some growth *** corollaries,some local characterization results for the quasi-Einstein metrics are derived.

关键词： Gradient quasi-Einstein soliton Cotton tensor Weyl tensor locally conformally flat

Wear mechanism and microstructures of Mo-implanted 4Cr5MoV1Si steel

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2004年第3期15卷 155-159页

作者： YANGJian-Hua ZHANGTong-He DepartmentofPhysics NantongInstituteofTechnology.Nantong226007 RadiationBeamandMaterialsEngineeringLab BeijingNormalUniversityBeijing100875

Mo ions extracted from a metal vapor vacuum arc ion source (MEVVA) were implanted into 4Cr5MoV1Si(H13) steel samples with a high implantation dose of 5×1017cm-2 and a pulsed ion beam flux of about 300 μA·cm-2·An optical interference microscope and pin-on-disc apparatus were used to investigate the wear and friction characteristics of the steel. The results from Rutherford backscattering spectroscopy (RBS) and the collision theory demonstrated that the radiation enhanced diffusion gave great influence on the Mo profile. It was observed by X-ray photoelectron spectroscopy (XPS) and grazing-angle X-ray diffraction (GXRD) that carbide of Mo appeared in the doped region for the implantation at 48 kV. The results showed that improvement in the wear resistance of the Mo-implanted steel were mainly due to the formation of Mo2C in the doped zone and the implantation affected zone underneath. Oxidation resistance of the surface iron and the surface with small crystal grains gave influences on the wear resistance in a way.

关键词：磨损阻抗微观结构离子注入钢铁 X射线光电子谱分析

Epithelial plasticity and cancer stem cells:Major mechanisms of cancer pathogenesis and therapy resistance

在线全文

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2017年第8期9卷 118-126页

作者： Minal Garg Department of Biochemistry University of LucknowLucknow 226007India

Epithelial-mesenchymal transition(EMT) has been linked with aggressive tumor biology and therapy resistance. It plays central role not only in the generation of cancer stem cells(CSCs) but also direct them across the multiple organ systems to promote tumor recurrence and metastasis. CSCs are reported to express stem cell genes as well as specific cell surfacemarkers and allow aberrant differentiation of *** facilitates cancer cells to leave primary tumor, acquire migratory characteristics, grow into new environment and develop radio-chemo-resistance. Based on the current information, present review discusses and summarizes the recent advancements on the molecular mechanisms that derive epithelial plasticity and its major role in generating a subset of tumor cells with stemness properties and pathophysiological spread of tumor. This paper further highlights the critical need to examine the regulation of EMT and CSC pathways in identifying the novel probable therapeutic *** improved therapeutic strategies based on the co-administration of inhibitors of EMT, CSCs as well as differentiated tumor cells may provide improved antineoplastic response with no tumor relapse.

关键词： Epithelial-mesenchymal transition Anticancer therapies Cancer stem cells Molecular pathogenesis Tumor relapse

Changes in Unsaturated Levels of Fatty Acids in Thylakoid PSII Membrane Lipids During Chilling-induced Resistance in Rice

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2007年第4期49卷 463-471页

作者： Su-Qin Zhu Chun-Mei Yu Xin-Yan Liu Ben-Hua Ji De-Mao Jiao Institute of Bioengineering Nantong University Nantong 226007 China College of Life Sciences Nantong University Nantong 226007 China Institute of Agrobiological Genetics and Physiology Jiangsu Academy of Agricultural Sciences Nanjing 210014 China

Temperature is one of the abiotic factors limiting growth and productivity of plants. In the present work, the effect of low non-freezing temperature, as an inducer of ＂chilling resistance＂, was studied in three cultivars of rice （Oryza sativa L.）, japonica cv. 9516 （j-9516）, the two parental lines of superhigh-yield hybrid rice between subspecies, Peiai/E32 （ji-PE）, and the traditional indica hybrid rice Shanyou 63 （i-SY63）. Leaves of chill-treated rice showed chilling-induced resistance, as an increase of their low-temperature tolerance was measured using chlorophyll fluorescence measurements, revealing a change in photosystem II （PSII） efficiency. After 5 d of exposure to 11 ~C under low light （100 pmol·m^-2·s^-1）, levels of unsaturated fatty acids in PSII thylakoid membrane lipids decreased during the initial 1-2 d, then increased slowly and reached 99.2%, 95.3% and 90.1% of the initial value （0 d） in j-9516, ji-PE and i-SY63, respectively, on the fifth day. However, under medium light （600 μmol·m^-2·s^-1）, all cultivars experienced similar substantial photoinhibition, which approached steady state levels after a decline in levels of unsaturated fatty acids in PSII thylakoid membrane lipids to about 57.1%, 53.8% and 44.5% of the initial values （0 d） in j-9516, ji-PE and i-SY63 on the fifth day. Under either chilling-induced resistance （the former） or low temperature photoinhibition （the latter） conditions, the changes of other physiological parameters such as D1 protein contents, electron transport activities of PSII （ETA）, Fv/Fm, xanthophyl cycle activities expressed by DES （deepoxide state） were consistent with that of levels of unsaturated fatty acids in PSII thylakoid membrane lipids. So there were negative correlations between saturated levels of fatty acids （16：1（3t）, 16：0, 18：0）, especially the 16：1（3t） fatty acid on thylakoid membrane and other physiological parameters, such as D1 protein contents, ETA and （A＋Z）/（A＋V＋Z）. A specific role of desaturation o

关键词： chilling-induced resistance D1 protein rice thylakoid PSII membrane lipids unsaturated fatty acids xanthophyl cycleactivity.

Palaeodiet of Miocene Producers and Depositional Environments:Inferences from the First Evidence of Microcoprolites from India

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2020年第5期94卷 1574-1590页

作者： Vivesh VKAPUR Kamlesh KUMAR P.MORTHEKAI Amritpal Singh CHADDHA Birbal Sahni Institute of Palaeosciences 53University RoadLucknowUttar Pradesh 226007India

This paper reviews research on coprolites from India,providing the first evidence of microcoprolites from the early Miocene(Aquitanian)Khari Nadi Formation sedimentary succession,exposed about 1.5 km northeast of the village of Kotada,Kachchh(Kutch)District,Gujarat State,western *** and size comparisons(in a statistical framework)with known coprolites from the Mesozoic-Cenozoic successions of India(including those recorded herein)and globally suggest that fishes were the likely producers of the Kotada *** electron microscopy confirms the presence of fish dental remains within the coprolites,while both Scanning Electron Microscopy(SEM)and Energy Dispersive X-ray Spectroscopy(EDS)reveal the phosphatic nature of the microscopic coprolite specimens(recorded herein)hinting that the producer(s)were predominantly carnivorous(ichthyophagous)in their ***,X-Ray Fluorescence(XRF)analysis of the host and associated lithologies allows us to deduce that the Kotada coprolites were deposited in a shallow marine environment,with possible aerial exposure of the host lithology occurring at some point after *** the best of our knowledge,the present report is the first record of microscopic fish coprolites from India,as well as being the first from the Aquitanian of India and the oldest Neogene record from India.

关键词： coprolites palaeodiet palaeoenvironment Energy Dispersive Spectroscopy(EDS) X-Ray Fluorescence(XRF)analysis Miocene(Aquitanian)

Investigating the Evolution of Cursive Script from Huang Xingjian＇ s Pencraft in Tang and Song Dynasty

在线全文

学校读者我要写书评

暂无评论

学术界 2015年第10期 289-294页

作者： Wu Xuehun School of Art Nantong University Nantong Jiangsu 226007

Cursive script has experienced a dramatic evolution in Song Dynasty,in which the expression changed from enthusiasm to rational description,thus the pencraft of cursive script and philosophy innovation also changed *** a representative calligrapher in Song Dynasty,Huang Tingjian has maintained the philosophy of "pencraft in script" and emphasized the standard of cursive *** the case of Huang' s perception of pencraft and his practical creation,we observed the transforming of calligraphy forms and a broader aesthetic connotation in Song Dynasty.

关键词：书法进化理念创新转化形式宋代黄庭坚

在线全文

学校读者我要写书评

暂无评论

双能CT材料分解图像在肺结节中的应用进展

分子影像学杂志 2025年第1期48卷 126-130页

作者：魏文恺崔磊南通大学医学院江苏南通226007 南通大学第二附属医院放射科江苏南通226000

肺癌是全球发病率最高的癌症之一,同时也是癌症的主要死亡原因,早期通常表现为肺结节。CT是评估肺结节的重要影像学检查方法。随着技术的进步,双能CT广泛应用于临床。通过获取两种不同能量谱的图像,双能CT实现材料分解,生成特定于材料... 详细信息

肺癌是全球发病率最高的癌症之一,同时也是癌症的主要死亡原因,早期通常表现为肺结节。CT是评估肺结节的重要影像学检查方法。随着技术的进步,双能CT广泛应用于临床。通过获取两种不同能量谱的图像,双能CT实现材料分解,生成特定于材料和能量的图像。现有研究表明,双能CT不仅可以用于鉴别肺结节良恶性、预测肺癌病理分型、肿瘤分化程度和肺癌基因表达,还可以评估肺癌疗效及预后。本文就双能CT材料分解图像在鉴别肺结节良恶性、预测肺癌病理分型、肿瘤分化程度、肺癌基因表达、疗效评估及预后等临床应用方面展开综述,旨在系统梳理双能CT材料分解图像在肺结节中的临床应用进展,为临床决策提供更科学准确的依据,推动肺癌精准医疗的进一步发展。

关键词：双能CT 肺结节肺肿瘤影像组学

维普期刊数据库博看期刊

同方期刊数据库

Effects of Anisotropy on Pair-wise Entanglement of a Four-Qubit Heisenberg XXZ Chain

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2006年第11期23卷 2888-2891页

作者：曹敏朱士群 School of Science Nantong University Nantong 226007 School of Physical Science and Technology Suzhou University Suzhou 215006

The pair-wise thermal entanglement in a four-qubit Heisenberg XXZ chain ＆ investigated to study the role of anisotropy when an external magnetic field is included. It is found that pair-wise entanglement is absent between nearest- and next-nearest neighbouring qubits with anisotropic parameter △≤-1. For two nearest-neighbouring qubits, increasing the parameter can not only induce the entanglement, but also extend the entanglement region in terms of magnetic field B and temperature T. For two next-nearest-neighbouring qubits, increasing anisotropic parameter can shift the location of the entanglement and control the extent of the entanglement in terms of magnetic field at a finite temperature.

关键词： THERMAL ENTANGLEMENT XYZ CHAIN MODELS

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

TBM常截面盘形滚刀破岩过程受力研究

人民长江 2025年第1期56卷 173-179,204页

作者：李忠艳刘杨张雯超吴志强李瑞红南通职业大学建筑工程学院江苏南通226007 苏州高新区(虎丘区)铁路建设服务中心江苏苏州215011 苏州大学轨道交通学院江苏苏州215131

针对目前工程上常用的常截面盘形滚刀受力分析问题,应用有限元方法建立了滚刀破岩的三维旋转切割模型,模拟滚刀破岩过程。通过计算得出常截面盘形滚刀破岩时的切削力,并与实验数据和文献数据进行比较,结果表明模拟的滚刀切削力与实际情... 详细信息

针对目前工程上常用的常截面盘形滚刀受力分析问题,应用有限元方法建立了滚刀破岩的三维旋转切割模型,模拟滚刀破岩过程。通过计算得出常截面盘形滚刀破岩时的切削力,并与实验数据和文献数据进行比较,结果表明模拟的滚刀切削力与实际情况较为吻合,验证了仿真模拟的可靠性。同时,滚刀破岩掘进试验结果表明,所测滚刀垂直力随时间变化曲线与仿真结果一致,呈波动特征,且滚刀切削力试验值与仿真数据误差较小。进一步将模拟数据与科罗拉多矿业大学(CSM)模型对比,发现整体结果较CSM模型值偏大,但与实验值更接近。通过对仿真模型岩石强度、掘进加载速率、刀刃宽度3个因素进行参数敏感性分析,得出在相同贯入度下,垂直力随上述因素的增大而提高,但掘进加载速率对垂直力的影响较小。相关成果可为TBM隧道的掘进设计与施工提供参考。

关键词：滚刀破岩切削力有限元掘进试验 CSM模型