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超导与化学
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作者 贾玉珍 《河北师范大学学报(自然科学版)》 CAS 1990年第3期122-127,共6页
1 超导与其发展史当前世界上出现了一股超导热,所谓“超导”是指导电材料在一定条件下电阻变为零的现象。自1911年发现超导现象以来,科学家已经意识到超导现象必将深远地影响未来科学技术的发展,成为各种新技术发展的关键。如用超导状... 1 超导与其发展史当前世界上出现了一股超导热,所谓“超导”是指导电材料在一定条件下电阻变为零的现象。自1911年发现超导现象以来,科学家已经意识到超导现象必将深远地影响未来科学技术的发展,成为各种新技术发展的关键。如用超导状态的电线制成闭合线圈,在这种超导线圈中由于没有电阻,故在无电压下电流仍能持续流动,因而可产生磁场,这种磁场即超导磁场。超导技术的应用包括超导强磁和超导弱磁。 展开更多
关键词 起导技术 化学
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美国开展超导在未来防卫系统中的应用研究
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作者 唐臻富 《电子对抗技术》 1989年第1期54-56,共3页
自从1911年荷兰物理学家、诺贝尔物理学奖获得者H.K.昂尼斯发现了超导电性以来,人们便开始了对超导电性的基本探索和认识性的研究。直到近两年制成了Tc高于液氮沸点的高温超导材料以后,人类才真正从此拉开了高温超导技术开发的序幕。就... 自从1911年荷兰物理学家、诺贝尔物理学奖获得者H.K.昂尼斯发现了超导电性以来,人们便开始了对超导电性的基本探索和认识性的研究。直到近两年制成了Tc高于液氮沸点的高温超导材料以后,人类才真正从此拉开了高温超导技术开发的序幕。就像著名的专家所预言的那样,“如能在常温下,例如在300K左右能实现超导电现象的话,现代文明的一切技术都将发生变化。”众所周知,任何军事武器系统总是对任何先进的新技术有特殊的敏感性。因此,超导技术的进展对未来军事防卫系统的影响,也必定受到关注。 展开更多
关键词 电机 起导技术 防卫系统
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超导技术在军事上的应用
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作者 孙晓亮 《世界导弹与航天》 北大核心 1990年第2期42-45,共4页
无论是利用较早出现的低温超导材料还是利用新出现的高温超导材料,超导技术在军用和民用产品上都有着广阔的应用前景,它可以被应用到许多重要的电子装置和大功率装置上。在军事方面,超导技术将用于弹道导弹潜艇、弹道导弹防御系统、反... 无论是利用较早出现的低温超导材料还是利用新出现的高温超导材料,超导技术在军用和民用产品上都有着广阔的应用前景,它可以被应用到许多重要的电子装置和大功率装置上。在军事方面,超导技术将用于弹道导弹潜艇、弹道导弹防御系统、反装甲作战武器、先进空面导弹和反潜武器等许多重要的军事系统上。下面介绍这项技术在电子技术和大功率装置领域的应用。 一、电子技术 军事和空间系统对电子装置。 展开更多
关键词 技术 起导技术 军事
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1988年日本高温超导研究开发的新进展
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作者 张景秀 《国际科技交流》 1989年第7期19-20,43,共3页
一 1988年,日本高温超导的有关研究和开发机构由争夺高温超导发现权的激烈竞争转向了重视基础的踏实研究阶段。国家对高温超导研究和开发投入了充足的经费。
关键词 高温起导 研究 日本
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用电泳法制YBCO厚膜 被引量:3
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作者 方家光 王蕾 +3 位作者 刘梦林 郭增 黄贺生 杨燕池 《低温与超导》 CAS CSCD 北大核心 1994年第3期22-25,共4页
电泳法是制备高温超导厚膜一种简便而又省钱的方法.我们已分别在4mm长300mm的银棒和50mm的银片上淀积出YBCO超导厚膜,它们在77K时,在微波场中显示出良好的超导性能。
关键词 厚膜 电泳法 高温起导材料
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为图书情报工作现代化做出贡献──纪念《现代图书情报技术》创刊五周年
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作者 武宁生 《现代图书情报技术》 CSSCI 北大核心 1989年第S1期4-5,共2页
关键词 《现代图书情报技术》 图书情报工作 现代化 信息工作 光盘技术 书馆学 国内外发展 技术决策 起导 单位制
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Mid-Course Guidance Law for Long Range Multi-Purpose Missiles
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作者 罗喜霜 张天桥 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期121-124,共4页
A useful mid course guidance law for long range multi purpose missiles is proposed. The law consists of two parts. One is used in the horizontal guidance plane, and the other in the vertical guidance plane. The mid ... A useful mid course guidance law for long range multi purpose missiles is proposed. The law consists of two parts. One is used in the horizontal guidance plane, and the other in the vertical guidance plane. The mid course is combined with variable structure proportional navigation in the homing phase. Simulation results show that the proposed guidance law can meet the demands for starting up the homing phase and so the handing over between mid course guidance and terminal guidance can be carried out successfully. 展开更多
关键词 multi purpose missile mid course guidance demands for startup
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溶解-凝胶法及其在无机新材料制备中的应用 被引量:1
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作者 别利剑 尹静 《临沂师专学报》 1994年第6期27-31,共5页
简要介绍了溶胶-疑使法的研究现状及其在无机新材料制备方面的应用,并在目前研究结果的基础上,提出了一些有待解决的问题.
关键词 溶胶-凝胶法 源物质 无机新材料 功能陶瓷 起导材料
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企业文化及其功能
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作者 姜兰波 《内蒙古宣传》 1992年第18期28-28,共1页
关键词 企业文化 企业成员 大雁矿务局 质量标准化 起导 向功能 企业精神 文化个体 群体思想 行为规范
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麻黄附子细辛汤配合电针介导TGF-β1/Smad通路调控钙通道改善窦房结纤维化
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作者 刘芳 王宇 王一钧 《解剖科学进展》 CAS 2023年第3期233-236,共4页
目的 探讨麻黄附子细辛汤配合电针对窦房结纤维化小鼠钙离子通道的影响及可能机制。方法 C57B6小鼠随机分为对照组(Control组)、模型组(Model组)、麻黄附子细辛汤配合电针治疗组(MFXE组);其中Model组、MFXE组饲养至18月龄进行实验,MFXE... 目的 探讨麻黄附子细辛汤配合电针对窦房结纤维化小鼠钙离子通道的影响及可能机制。方法 C57B6小鼠随机分为对照组(Control组)、模型组(Model组)、麻黄附子细辛汤配合电针治疗组(MFXE组);其中Model组、MFXE组饲养至18月龄进行实验,MFXE组灌胃麻黄附子细辛汤配合电针处理,持续21天。电生理仪监测各组小鼠心率;取心脏窦房结,分别进行HE、Masson染色,观察窦房结病理损伤及纤维化程度;Western blot检测Klotho、Trpv3、Trpv6蛋白的表达;Western blot与qRT-PCR方法检测TGF-β1/Smad通路相关TGF-β1、Smad2、Smad3和Smad7蛋白和mRNA的表达。结果 麻黄附子细辛汤配合电针治疗能够提高窦房结纤维化小鼠的心率,从而改善窦房结纤维化损伤,同时上调Klotho蛋白的表达,增加钙通道调节蛋白Trpv3、Trpv6蛋白的表达,抑制TGF-β1、Smad2、Smad3蛋白表达。结论 麻黄附子细辛汤配合电针通过调控TGF-β1/Smad通路降低窦房结纤维化损伤,促进窦房结纤维化小鼠的钙离子转运。 展开更多
关键词 麻黄附子细辛汤 电针治疗 窦房结纤维化 TGF-β1/Smad通路 钙通道 C57B6小鼠
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Crack initiation rate of brittle rock under thermal-hydro-mechanical coupling condition 被引量:2
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作者 Zhuo LI Qiu-hua RAO +1 位作者 Peng LI Wei YI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第10期2107-2113,共7页
A calculation formula of thermal-hydro-mechanical(THM)coupling crack initiation rate for brittle rock was derived based on the energy conservation law.The self-designed THM coupling fracture test with conductive adhe... A calculation formula of thermal-hydro-mechanical(THM)coupling crack initiation rate for brittle rock was derived based on the energy conservation law.The self-designed THM coupling fracture test with conductive adhesive electrical measurement method was applied to measuring the THM coupling crack propagation rate of brittle rock continuously.Research results show that both calculation and test results of crack initiation rate increased with increase of the temperature and the hydraulic pressure.They are almost in good agreement,which can prove validity of the calculation formula of THM coupling crack initiation rate. 展开更多
关键词 crack initiation rate thermal-hydro-mechanical coupling test conductive adhesive electrical method fracture mechanism brittle rock
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Wilson's disease: Prospective developments towards new therapies 被引量:6
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作者 Giusy Ranucci Roman Polishchuck Raffaele Iorio 《World Journal of Gastroenterology》 SCIE CAS 2017年第30期5451-5456,共6页
Wilson's disease(WD) is an autosomal recessive disorder of copper metabolism, caused by mutations in the ATP7 B gene. A clear demand for novel WD treatment strategies has emerged. Although therapies using zinc sal... Wilson's disease(WD) is an autosomal recessive disorder of copper metabolism, caused by mutations in the ATP7 B gene. A clear demand for novel WD treatment strategies has emerged. Although therapies using zinc salts and copper chelators can effectively cure WD, these drugs exhibit limitations in a substantial pool of WD patients who develop intolerance and/or severe side effects. Several lines of research have indicated intriguing potential for novel strategies and targets for development of new therapies. Here, we review these new approaches, which comprise correction of ATP7 B mutants and discovery of new compounds that circumvent ATP7B-deficiency, as well as cell and gene therapies. We also discuss whether and when these new therapeutic strategies will be translated into clinical use, according to the key requirements for clinical trials that remain to be met. Finally, we discuss the hope for the current rapidly developing research on molecular mechanisms underlying WD pathogenesis and for the related potential therapeutic targets to provide a solid foundation for the next generation of WD therapies that may lead to an effective, tolerable and safe cure. 展开更多
关键词 ATP7B Stem cell-derived hepatocyte like cells Methanobactin Heat shock protein 70 p38 JNK CORRECTORS Translational medicine Precision medicine
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Effects of prostaglandin F_(2α) on small intestinal interstitial cells of Cajal 被引量:1
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作者 Chan Guk Park Young Dae Kim +5 位作者 Man Yoo Kim Jae Woong Koh Jae Yeoul Jun Cheol Ho Yeum Insuk So Seok Choi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第9期1143-1151,共9页
AIM:To explore the role of prostaglandin F2α(PGF2α) on pacemaker activity in interstitial cells of Cajal(ICC)from mouse small intestine. METHODS:In this study,effects of PGF2αin the cultured ICC cells were in... AIM:To explore the role of prostaglandin F2α(PGF2α) on pacemaker activity in interstitial cells of Cajal(ICC)from mouse small intestine. METHODS:In this study,effects of PGF2αin the cultured ICC cells were investigated with patch clamp technology combined with Ca 2+ image analysis. RESULTS:Externally applied PGF2α(10μmol/L)produced membrane depolarization in current-clamp mode and increased tonic inward pacemaker currents in voltage-clamp mode.The application of flufenamic acid(a non-selective cation channel inhibitor)or niflumic acid(aCl channel inhibitor)abolished the generation of pacemaker currents but only flufenamic acid inhibited the PGF2α-induced tonic inward currents.In addition,the tonic inward currents induced by PGF2αwere not inhibited by intracellular application of 5’-[-thio]diphosphate trilithium salt.Pretreatment with Ca 2+ free solution, U-73122,an active phospholipase C inhibitor,and thapsigargin,a Ca 2+ -ATPase inhibitor in endoplasmic reticulum,abolished the generation of pacemaker currents and suppressed the PGF2α-induced tonic inward currents.However,chelerythrine or calphostin C,protein kinase C inhibitors,did not block the PGF2α-induced effects on pacemaker currents.When recording intracellular Ca 2+ ([Ca 2+ ]i)concentration using fluo-3/AM,PGF2α broadly increased the spontaneous[Ca 2+ ]i oscillations. CONCLUSION:These results suggest that PGF2αcan modulate pacemaker activity of ICC by acting non-selective action channels through phospholipase C-dependent pathway via[Ca2+]i regulation 展开更多
关键词 Prostaglandin F2α Interstitial cells of Cajal Tonic inward currents Intestinal motility
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Surgical Removal of a Giant Vegetation on Permanent Endocavitary Pacemaker Wire and Lead
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作者 Guo-tao Ma Qi Miao Chao-ji Zhang Li-hua Cao 《Chinese Medical Sciences Journal》 CAS CSCD 2011年第4期251-253,共3页
PACEMAKER lead infections are rare.There are only about 0.4%-1.1% of the patients who have been implanted permanent pacemakers suffering from serious infections which lead to endocarditis.1 Generally,removal of the ... PACEMAKER lead infections are rare.There are only about 0.4%-1.1% of the patients who have been implanted permanent pacemakers suffering from serious infections which lead to endocarditis.1 Generally,removal of the infected pacemaker wire and lead,long-term anti-infection therapy,and implantation of a new pacemaker to another anatomic site are accepted approaches for these patients. 展开更多
关键词 pacemaker lead VEGETATION Scopulariopsis sp VORICONAZOLE
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Franck-Condon Factors and Band Origins for MgH in the A2П-X2∑+ System
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作者 Xu Cheng Jiao Bai +1 位作者 Jian-ping Yin Hai-ling Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第3期253-256,I0001,共5页
We measure the dispersed spectrum of the A2H-X2E+ system of MgH using laser abla- tion/laser induced Fluorescence method and obtain the Frank-Condon factors and related transition frequencies of the A2H(v'=0)-X2... We measure the dispersed spectrum of the A2H-X2E+ system of MgH using laser abla- tion/laser induced Fluorescence method and obtain the Frank-Condon factors and related transition frequencies of the A2H(v'=0)-X2∑+(v"=0,1) system by analyzing the experimental spectrum. Also, we calculate the Franck-Condon factors and transition frequencies of the A2H-X2∑+ system of MgH. A comparison of our theoretical calculation and experimental results with other reported theoretical results was carried out as well. 展开更多
关键词 Franck-Condon factors Energy curve Vibrational frequencies Dispersed fluorescence
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掺Eu^(3+)的Tl-Ba-Ca-Cu-O系高T_c超导材料的X射线衍射研究
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作者 周衡南 丁世英 +2 位作者 余正 周礼 陈峻 《科学通报》 EI CAS CSCD 北大核心 1990年第22期1710-1712,共3页
自从Maeda等发现无稀土高温超导材料Bi-Sr-Ca-Cu-O系后,Sheng等相继发现了另一类Tl-Ba-Ca-Cu-O系高温超导材料,其超导转变温度似乎更高一些,其结构也非常相似,均存在二、三个超导相,相应的T_c分别为~85K和110K或更高一点;而相的化学组... 自从Maeda等发现无稀土高温超导材料Bi-Sr-Ca-Cu-O系后,Sheng等相继发现了另一类Tl-Ba-Ca-Cu-O系高温超导材料,其超导转变温度似乎更高一些,其结构也非常相似,均存在二、三个超导相,相应的T_c分别为~85K和110K或更高一点;而相的化学组分则分别为2212和2223,或其它化学配比关系,通常分别称之为低温相和高温相。 展开更多
关键词 高TC 起导材料 X射线衍射 EU
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高T_c氧化物体系的相关系和晶体结构 被引量:1
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作者 梁敬魁 《物理》 CAS 北大核心 1989年第11期641-651,共11页
本文综述了R-Ba-Cu-O体系,Bi-Sr-Ca-Cu-O体系,T1-Ba-Ca-Cu-O #系,T1-Sr-Ca-R-Cu-O体系以及Pb-Sr-R(Ca)Cu-O体系超导相的相关系和晶体结构,并讨论了超导相的结... 本文综述了R-Ba-Cu-O体系,Bi-Sr-Ca-Cu-O体系,T1-Ba-Ca-Cu-O #系,T1-Sr-Ca-R-Cu-O体系以及Pb-Sr-R(Ca)Cu-O体系超导相的相关系和晶体结构,并讨论了超导相的结构特点和它们之间的相互关系. 展开更多
关键词 氧化物 起导 相关系
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Potassium-induced bifurcations and chaos of firing patterns observed from biological experiment on a neural pacemaker 被引量:11
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作者 GU HuaGuang CHEN ShengGen 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第5期864-871,共8页
Changes of neural firing patterns and transitions between firing patterns induced by the introduction of external stimulation or adjustment of biological parameter have been demonstrated to play key roles in informati... Changes of neural firing patterns and transitions between firing patterns induced by the introduction of external stimulation or adjustment of biological parameter have been demonstrated to play key roles in information coding.In this paper,bifurcation processes of bursting patterns were observed from an experimental neural pacemaker,through the adjustment of potassium parameter including ion concentration and calcium-dependent channel conductance.The adjustment of calcium-dependent potassium channel conductance was achieved by changing the extracellular tetraethylammonium concentration.The deterministic dynamics of chaotic bursting patterns induced by period-doubling bifurcation and intermittency,and lying between two periodic bursting patterns in a period-adding bifurcation process was investigated with a nonlinear prediction method.The bifurcations included period-doubling and period-adding bifurcations of bursting patterns.The experimental bifurcations and chaos closely matched those previously simulated in the theoretical neuronal model by adjusting potassium parameter,which demonstrated the simulation results of the theoretical model.The experimental results indicate that the potassium concentration and conductance of calcium-dependent potassium channel can induce bifurcations of the neural firing patterns.The potential role of these bifurcation structures in neural information coding mechanism is discussed. 展开更多
关键词 BIFURCATION neural firing pattern CHAOS potassium ion
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Predator-induced phenotypic plasticity of shape and behavior: parallel and unique patterns across sexes and species 被引量:1
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作者 Heather A. ARNETT Michael T. KINNISON 《Current Zoology》 SCIE CAS CSCD 2017年第4期369-378,共10页
Phenotypic plasticity is often an adaptation of organisms to cope with temporally or spatially heter- ogenous landscapes. Like other adaptations, one would predict that different species, populations, or sexes might t... Phenotypic plasticity is often an adaptation of organisms to cope with temporally or spatially heter- ogenous landscapes. Like other adaptations, one would predict that different species, populations, or sexes might thus show some degree of parallel evolution of plasticity, in the form of parallel reaction norms, when exposed to analogous environmental gradients. Indeed, one might even ex- pect parallelism of plasticity to repeatedly evolve in multiple traits responding to the same gradi- ent, resulting in integrated parallelism of plasticity. In this study, we experimentally tested for paral- lel patterns of predator-mediated plasticity of size, shape, and behavior of 2 species and sexes of mosquitofish. Examination of behavioral trials indicated that the 2 species showed unique patterns of behavioral plasticity, whereas the 2 sexes in each species showed parallel responses. Fish shape showed parallel patterns of plasticity for both sexes and species, albeit males showed evidence of unique plasticity related to reproductive anatomy. Moreover, patterns of shape plasticity due to predator exposure were broadly parallel to what has been depicted for predator-mediated popula- tion divergence in other studies (slender bodies, expanded caudal regions, ventrally located eyes, and reduced male gonopodia). We did not find evidence of phenotypic plasticity in fish size for ei- ther species or sex. Hence, our findings support broadly integrated parallelism of plasticity for sexes within species and less integrated parallelism for species. We interpret these findings with respect to their potential broader implications for the interacting roles of adaptation and constraint in the evolutionary origins of parallelism of plasticity in general. 展开更多
关键词 BOLDNESS common garden geometric morphometrics reaction norm sexual dimorphism size at maturity.
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Dongsha erosive channel on northern South China Sea Shelf and its induced Kuroshio South China Sea Branch 被引量:11
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作者 LUAN XiWu ZHANG Liang PENG XueChao 《Science China Earth Sciences》 SCIE EI CAS 2012年第1期149-158,共10页
Based on a data base of multi-channel seismic profiles covered over Dongsha plateau of the northern South China Sea margin, we found that the sea bed morphology of northern South China Sea margin had been changed dram... Based on a data base of multi-channel seismic profiles covered over Dongsha plateau of the northern South China Sea margin, we found that the sea bed morphology of northern South China Sea margin had been changed dramatically after Dongsha uplifting, that sedimentary layer since Miocene age had been eroded with maximum eroded thickness more than 1000 m, and that an erosive channel had been formed of 20 km in width and 200 km in length and several hundreds meters in depth on the outer shelf of northern South China Sea. The erosive channel is parallel to the 600 m isobath line, stretching from northeast to the southwest north of Dongsha uplift. The Kuroshio intrudes the South China Sea through Luzon Strait both in winter time and summer time, and in the northern South China Sea margin area, the intruded Kuroshio Branch takes the form of Pacific-Indian Ocean Through Flow (PITH) in winter time, while the Luzon Strait Subsurface Inflow (LSSIF) in summer time, the routes of both PITH and LSSIF coincide well with the distribution of the erosive channel. After climbing from the northern slope up to the northern shelf, and after joined by the southward flow from the middle northern shelf of South China Sea, the Kuroshio Branch is strengthened and thus is able to erode the sea floor, and the shape of the erosive channel is a result of the long-term interaction between the Kuroshio South China Sea Branch and the Dongsha outer shelf sea floor. 展开更多
关键词 Northern South China Sea margin Dongsha Uplift erosion Dongsha erosive channel Kuroshio South China Sea Branch
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