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Recent Progress in Studies of the Variabilities and Mechanisms of the East Asian Monsoon in a Changing Climate 预览
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作者 Wen CHEN Lin WANG +4 位作者 Juan FENG Zhiping WEN Tiaojiao MA Xiuqun YANG Chenghai WANG 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第9期887-901,共15页
Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community... Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community and is particularly challenging in a changing climate where the global mean temperature has been rising.Recent advances in studies of the variabilities and mechanisms of the EAM are reviewed in this paper,focusing on the interannual to interdecadal time scales.Some new results have been achieved in understanding the behaviors of the EAM,such as the evolution of the East Asian summer monsoon(EASM),including both its onset and withdrawal over the South China Sea,the changes in the northern boundary activity of the EASM,or the transitional climate zone in East Asia,and the cycle of the EASM and the East Asian winter monsoon and their linkages.In addition,understanding of the mechanism of the EAM variability has improved in several aspects,including the impacts of different types of ENSO on the EAM,the impacts from the Indian Ocean and Atlantic Ocean,and the roles of mid-to high-latitude processes.Finally,some scientific issues regarding our understanding of the EAM are proposed for future investigation. 展开更多
关键词 EAST ASIAN summer MONSOON EAST ASIAN winter MONSOON CHANGING CLIMATE MONSOON onset and withdrawal transitional CLIMATE zone different types of ENSO erent types of ENSO
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EAST柔性机械手臂体数据采集系统设计 预览
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作者 刘武常 杨婵娟 《自动化技术与应用》 2019年第5期92-95,共4页
柔性机械手由机械臂体和执行器组成,在EAST装置的正常运行与维护中作用重大,该设备臂体需达到定位精度高及耐高温的要求,据此本文完成了位姿数据采集系统的设计,该系统主要采用磁线性编码器芯片和倾角传感器芯片,实现了臂体姿态的精确定... 柔性机械手由机械臂体和执行器组成,在EAST装置的正常运行与维护中作用重大,该设备臂体需达到定位精度高及耐高温的要求,据此本文完成了位姿数据采集系统的设计,该系统主要采用磁线性编码器芯片和倾角传感器芯片,实现了臂体姿态的精确定位,与上位机通过CAN总线方式实现数据交换,可在高温环境下正常工作(115℃),系统整体控制过程及读取传感器信号主要由主控芯片完成,为采集电机的外表温度,结合温度传感器Pt100设计了调理电路,通过对高温、定位和姿态方面进行试验,结果表明该系统准确性较高且耐高温,满足设计的要求。 展开更多
关键词 柔性机械手 EAST 磁线性编码器 传感器
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EAST液态锂试验测试平台磁体系统的MATLAB辅助设计
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作者 胡乐星 杨庆喜 +3 位作者 宋云涛 宋伟 左桂忠 胡建生 《机械设计》 CSCD 北大核心 2019年第3期19-23,共5页
为了设计一套液态锂台面试验测试平台磁体系统,并保证磁体线圈的安全稳定运行,采用了MATLAB对其进行辅助设计,并对计算结果进行了校核计算。通过对线圈产生的磁场及其电参数和水参数的计算,可知:线圈的安匝数、线圈半径等对线圈磁场的... 为了设计一套液态锂台面试验测试平台磁体系统,并保证磁体线圈的安全稳定运行,采用了MATLAB对其进行辅助设计,并对计算结果进行了校核计算。通过对线圈产生的磁场及其电参数和水参数的计算,可知:线圈的安匝数、线圈半径等对线圈磁场的分布、冷却水的流速及平台的综合成本具有显著的影响。计算结果对于磁体线圈的参数设计,以及冷却水泵和电源的选型具有重要的指导意义。 展开更多
关键词 EAST 液态锂限制器 测试平台 亥姆霍兹线圈
EAST新型下偏滤器冷却结构传热性能数值模拟 预览
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作者 徐厚昌 李磊 +5 位作者 姚达毛 周自波 曹磊 许铁军 韩乐 訾鹏飞 《核聚变与等离子体物理》 CAS CSCD 北大核心 2019年第2期127-133,共7页
为实现EAST装置超400s长脉冲高约束模、10MW加热功率下的稳态运行,需对现有的下碳偏滤器进行升级改造,拟采用钨串结极水冷却系统,热通量控制在水冷钨铜第一壁材料允许的稳态的10MW·m^-2。在对下钨偏滤器的冷却结极传热性能进行数... 为实现EAST装置超400s长脉冲高约束模、10MW加热功率下的稳态运行,需对现有的下碳偏滤器进行升级改造,拟采用钨串结极水冷却系统,热通量控制在水冷钨铜第一壁材料允许的稳态的10MW·m^-2。在对下钨偏滤器的冷却结极传热性能进行数值模拟仿真研究的基础上,研究了多种以钨串单元为基础的冷却结极,提出了一种新型下钨偏滤器水冷结极设计,幵建立了满足传热要求的EAST装置新型下钨偏滤器单元结构模型。 展开更多
关键词 EAST 等离子体 鸭偏滤器 水冷 传热分析
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2018 update of expert consensus statement on antiplatelet therapy in East Asian patients with ACS or undergoing PCI
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作者 Yong Huo Young-Hoon Jeong +16 位作者 Yanjun Gong Daowen Wang Ben He Jiyan Chen Guosheng Fu Yundai Chen Jianping Li Yi Li Shinya Goto Udaya S.Tantry Paul A.Gurbel Jong-Hwa Ahn Hyo-Soo Kim Myung Ho Jeong Yaling Han Sidney C.Smith Jr. Junbo Ge 《科学通报:英文版》 SCIE EI CSCD 2019年第3期166-179,共14页
East Asians are the most populous race in the world and their health status is an important global issue.Compared with Caucasian populations, East Asian patients have a different benefit/risk ratio when using antithro... East Asians are the most populous race in the world and their health status is an important global issue.Compared with Caucasian populations, East Asian patients have a different benefit/risk ratio when using antithrombotic treatment. Despite this observation, treatment strategies in East Asian patients are mostly based on the American and European guidelines. Despite a lower platelet inhibitory response to clopidogrel, East Asian patients show a similar or even a lower rate of ischemic event occurrence and higher bleeding risk compared with Caucasian patients. For potent P2Y12 inhibitors(ticagrelor and prasugrel),East Asian patients have shown less favorable net clinical benefits compared with Caucasian patients,which may be related to differences in pharmacokinetic/pharmacodynamic profiles and therapeutic zone of antiplatelet effect. This updated consensus mainly focuses on state-of-the-art and current controversies in the East Asian population. In addition, when East Asian patients are administered potent P2Y12 receptor inhibitors, the strategies and ongoing trials to overcome the related hurdles are discussed. 展开更多
关键词 East Asian CORONARY artery disease ANTIPLATELET BLEEDING
透平膨胀机控制系统设计 预览
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作者 付贤政 袁恺 《淮南师范学院学报》 2019年第2期107-109,共3页
氦透平膨胀机是氦制冷机的关键部件,它的工作效率以及稳定性直接影响氦制冷机的各项性能指标。EAST托卡马克装置低温系统中原有四台俄罗斯透平制动性能较差,故障率高,严重影响着低温系统的稳定性。通过调研,从捷克PBS公司购买一台透平... 氦透平膨胀机是氦制冷机的关键部件,它的工作效率以及稳定性直接影响氦制冷机的各项性能指标。EAST托卡马克装置低温系统中原有四台俄罗斯透平制动性能较差,故障率高,严重影响着低温系统的稳定性。通过调研,从捷克PBS公司购买一台透平代替原有的透平D。文章主要完成了新透平控制系统的设计以及运行调试,为后续透平的更换奠定了基础。 展开更多
关键词 先进实验超导托卡马克 低温系统 透平膨胀机
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Calculation of the heat flux in the lower divertor target plate using an infrared camera diagnostic system on the experimental advanced superconducting tokamak 预览
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作者 Zhi-Xue Cui Xin Li +3 位作者 Shuang-Bao Shu Jia-Rong Luo Mei-Wen Chen Yu-Zhong Zhang 《核技术:英文版》 SCIE CAS CSCD 2019年第6期63-69,共7页
During the discharging of Tokamak devices, interactions between the core plasma and plasma-facing components (PFCs) may cause exorbitant heat deposition in the latter. This poses a grave threat to the lifetimes of PFC... During the discharging of Tokamak devices, interactions between the core plasma and plasma-facing components (PFCs) may cause exorbitant heat deposition in the latter. This poses a grave threat to the lifetimes of PFCs materials. An infrared (IR) diagnostic system consisting of an IR camera and an endoscope was installed on an Experimental Advanced Superconducting Tokamak (EAST) to monitor the surface temperature of the lower divertor target plate (LDTP) and to calculate the corresponding heat flux based on its surface temperature and physical structure, via the finite element method. First, the temperature obtained by the IR camera was calibrated against the temperature measured by the built-in thermocouple of EAST under baking conditions to determine the true temperature of the LDTP. Next, based on the finite element method, a target plate model was built and a discretization of the modeling domain was carried out. Then, a heat conduction equation and boundary conditions were determined. Finally, the heat flux was calculated. The new numerical tool provided results similar to those for DFLUX;this is important for future work on related physical processes and heat flux control. 展开更多
关键词 EAST DIVERTOR TARGET PLATE INFRARED CAMERA Heat FLUX Finite element analysis
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Concentration and Characterization of Colored Dissolved Organic Matter in the Surface Microlayer and Subsurface Water of the Yellow Sea and the East China Sea 预览
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作者 ZHANG Jing ZHAO Junjie +1 位作者 YANG Guipeng LIU Weifeng 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第2期383-393,共11页
The distribution and chemical properties of colored dissolved organic matter(CDOM)in the Yellow Sea and the East China Sea during December 2011-January 2012 were investigated.The input of freshwater and biological act... The distribution and chemical properties of colored dissolved organic matter(CDOM)in the Yellow Sea and the East China Sea during December 2011-January 2012 were investigated.The input of freshwater and biological activities had an evident influence on the CDOM levels(characterized by the light absorption coefficient at the wavelength of 355 nm a355)in the study area.The spatial distribution of CDOM levels displayed a gradually decreasing trend from the coastal waters(0.37m^-1)to the open sea(0.18m^-1).The spectral slope ratio(the slope ratio SR defined as S275-295:S350-400)during the cruise was correlated with salinity,and exhibited a large variation from inshore(average of 2.515)to offshore sites(average of 5.327)compared with the distribution of a355.The values of SR were related to CDOM molecular weight(MW).The a355,SR,and chlorophyll a in 37 samples collected from the surface microlayer were significantly correlated with those in the corresponding subsurface water samples,implying a strong exchange action between the microlayer and bulk water.The a355 and SR of CDOM exhibited significant microlayer enrichment,with mean enrichment factors(EFs)of 1.72 and 1.62,respectively. 展开更多
关键词 COLORED dissolved organic matter(CDOM) absorption coefficient SPECTRAL SLOPE ratio Yellow SEA East China SEA
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Improvements in Long-Lead Prediction of Early-Summer Subtropical Frontal Rainfall Based on Arctic Sea Ice 预览
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作者 XING Wen HUANG Fei 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期542-552,共11页
Seasonal prediction of East Asia(EA) summer rainfall, especially with a longer-lead time, is in great demand, but still very challenging. The present study aims to make long-lead prediction of EA subtropical frontal r... Seasonal prediction of East Asia(EA) summer rainfall, especially with a longer-lead time, is in great demand, but still very challenging. The present study aims to make long-lead prediction of EA subtropical frontal rainfall(SFR) during early summer(May-June mean, MJ) by considering Arctic sea ice(ASI) variability as a new potential predictor. A MJ SFR index(SFRI), the leading principle component of the empirical orthogonal function(EOF) analysis applied to the MJ precipitation anomaly over EA, is defined as the predictand. Analysis of 38-year observations(1979-2016) revealed three physically consequential predictors. A stronger SFRI is preceded by dipolar ASI anomaly in the previous autumn, a sea level pressure(SLP) dipole in the Eurasian continent, and a sea surface temperature anomaly tripole pattern in the tropical Pacific in the previous winter. These precursors foreshadow an enhanced Okhotsk High, lower local SLP over EA, and a strengthened western Pacific subtropical high. These factors are controlling circulation features for a positive SFRI. A physical-empirical model was established to predict SFRI by combining the three predictors. Hindcasting was performed for the 1979-2016 period, which showed a hindcast prediction skill that was, unexpectedly, substantially higher than that of a four-dynamical models’ ensemble prediction for the 1979-2010 period(0.72 versus 0.47). Note that ASI variation is a new predictor compared with signals originating from the tropics to mid-latitudes. The long-lead hindcast skill was notably lower without the ASI signals included, implying the high practical value of ASI variation in terms of long-lead seasonal prediction of MJ EA rainfall. 展开更多
关键词 East Asia SUBTROPICAL FRONTAL rainfall long-lead seasonal PREDICTION Arctic sea ice Physical-empirical model
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Middle East respiratory syndrome coronavirus in pediatrics: a report of seven cases from Saudi Arabia
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作者 Sarah H. Alfaraj Jaffar A. Al-Tawfiq +1 位作者 Talal A. Altuwaijri Ziad A. Memish 《医学前沿:英文版》 CAS CSCD 2019年第1期126-130,共5页
Infection with Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in 2012 as an important respiratory disease with high fatality rates of 40%—60%. Despite the increased number of cases over subsequent ye... Infection with Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in 2012 as an important respiratory disease with high fatality rates of 40%—60%. Despite the increased number of cases over subsequent years, the number of pediatric cases remained low. A review of studies conducted from June 2012 to April 19, 2016 reported 31 pediatric MERS-CoV cases. In this paper, we present the clinical and laboratory features of seven patients with pediatric MERS. Five patients had no underlying medical illnesses, and three patients were asymptomatic. Of the seven cases, four (57%) patients sought medical advice within 1-7 days from the onset of symptoms. The three other patients (43%) were asymptomatic and were in contact with patients with confirmed diagnosis of MERS-CoV. The most common presenting symptoms were fever (57%), cough (14%), shortness of breath (14%), vomiting (28%), and diarrhea (28%). Two (28.6%) patients had platelet counts of < 150 ×10^9/L, and one patient had an underlying end-stage renal disease. The remaining patients presented with normal blood count, liver function, and urea and creatinine levels. The documented MERS-CoV Ct values were 32 38 for four of the seven cases. Two patients (28.6%) had abnormal chest radiographic findings of bilateral infiltration. One patient (14.3%) required ventilator support, and two patients (28.6%) required oxygen supplementation. All the seven patients were discharged without complications. 展开更多
关键词 Middle East RESPIRATORY SYNDROME CORONAVIRUS MERS-CoV pregnancy PEDIATRICS
Development Optimization for a Typical Carbonate Reservoir in the Middle East 预览
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作者 Wei Chenji Yang Jian +2 位作者 Liu Shuangshuang Li Zhengzhong Lou Yuankeli 《中国油气:英文版》 CAS 2019年第1期29-36,共8页
Belt and Road initiative is a very important strategy for Chinese companies to cooperate with foreign ones.The Middle East is a region that contains abundant oil and gas resources. Meanwhile, many countries in the Mid... Belt and Road initiative is a very important strategy for Chinese companies to cooperate with foreign ones.The Middle East is a region that contains abundant oil and gas resources. Meanwhile, many countries in the Middle East support and join in the Belt and Road initiative. Since oil and gas resources are of vital significance for Chinese industry,the cooperation in oil and gas with countries in the Middle East is an important part in ’Belt and Road’ initiative. CNPC began its overseas business from the year 1993 and now it keeps cooperating with many countries in the Middle East. UAE has a large amount of oil and gas reserves and after evaluation, CNPC became the shareholder of ADNOC Onshore and gained 8% of the stocks.In order to improve the development effect, ADNOC appointed several international oil companies as asset leaders for four assets. As a reward, each asset leader can have more income and less tax. As a result, CNPC decided to compete for NEB asset leader with other international oil companies. After analyzing the current development plan, our group conducted the optimization scheme for NEB asset that can help improve the current situation and enhance oil recovery.The optimization scheme is divided into three steps. First is the establishment of effective drainage system.Second is to control water cut and GOR. Third is to enhance oil recovery factor based on first two steps. After discussion with the research group of ADNOC, they admitted that our strategy can solve the problems. Finally, CNPC obtained the asset leader, and has more impact on UAE oil and gas industry since then. 展开更多
关键词 MIDDLE East CARBONATE Reservoir NEB ASSET LEADER
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Pathways of Influence of the Northern Hemisphere Mid–high Latitudes on East Asian Climate:A Review 预览
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作者 Jianping LI Fei ZHENG +2 位作者 Cheng SUN Juan FENG Jing WANG 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第9期902-921,共20页
This paper reviews recent progress made by Chinese scientists on the pathways of influence of the Northern Hemisphere mid-high latitudes on East Asian climate within the framework of a“coupled oceanic-atmospheric(lan... This paper reviews recent progress made by Chinese scientists on the pathways of influence of the Northern Hemisphere mid-high latitudes on East Asian climate within the framework of a“coupled oceanic-atmospheric(land-atmospheric or seaice-atmospheric)bridge”and“chain coupled bridge”.Four major categories of pathways are concentrated upon,as follows:Pathway A—from North Atlantic to East Asia;Pathway B—from the North Pacific to East Asia;Pathway C—from the Arctic to East Asia;and Pathway D—the synergistic effects of the mid-high latitudes and tropics.In addition,definitions of the terms“combined effect”,“synergistic effect”and“antagonistic effect”of two or more factors of influence or processes and their criteria are introduced,so as to objectively investigate those effects in future research. 展开更多
关键词 East Asian climate Northern HEMISPHERE mid-high LATITUDES COUPLED oceanic-land-sea-ice-atmospheric BRIDGE chain COUPLED BRIDGE pathway synergistic effect
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Plasma shape optimization for EAST tokamak using orthogonal method
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作者 陈远洋 鲍晓华 +1 位作者 傅鹏 高格 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第1期453-459,共7页
It is necessary to reduce the currents of poloidal field(PF) coils as small as possible, during the static equilibrium design procedure of Experimental Advanced Superconductive Tokamak(EAST). The quasi-snowflake(QSF) ... It is necessary to reduce the currents of poloidal field(PF) coils as small as possible, during the static equilibrium design procedure of Experimental Advanced Superconductive Tokamak(EAST). The quasi-snowflake(QSF) divertor configuration is studied in this paper. Starting from a standard QSF plasma equilibrium, a new QSF equilibrium with 300 kA total plasma current is designed. In order to reduce the currents of PF6 and PF14, the influence of plasma shape on PF coil current distribution is analyzed. A fixed boundary equilibrium solver based on a non-rigid plasma model is used to calculate the flux distribution and PF coil current distribution. Then the plasma shape parameters are studied by the orthogonal method. According to the result, the plasma shape is redefined, and the calculated equilibrium shows that the currents of PF6 and PF14 are reduced by 3.592 kA and 2.773 kA, respectively. 展开更多
关键词 EAST PLASMA SHAPE ORTHOGONAL method PLASMA EQUILIBRIUM CALCULATION
The Hong Kong–Zhuhai–Macao Bridge 预览
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作者 Yongling Zhu Ming Lin +2 位作者 Fanchao Meng Xiaodong Liu Wei Lin 《工程(英文)》 2019年第1期10-14,共5页
The Hong Kong–Zhuhai–Macao Bridge (HZMB) is located at the Pearl River Estuary on the southeast coast of China;it is the longest as-build marine crossings made of island, tunnel, and bridge. It links Hong Kong in th... The Hong Kong–Zhuhai–Macao Bridge (HZMB) is located at the Pearl River Estuary on the southeast coast of China;it is the longest as-build marine crossings made of island, tunnel, and bridge. It links Hong Kong in the east with Zhuhai–Macao in the west with a total length of 55 km. The link was built according to the highway standard of six lanes with three lanes going each way;it has a design speed of 100 km·h^-1 and a design life of 120 years. The HZMB has improved traffic conditions on the east and west sides of the coast of the Pearl River Estuary and strengthened the communication, transportation, and economic integration of the three regions, thus accelerating the formation of the Guangdong–Hong Kong–Macao Greater Bay Area. This paper introduces the design and construction of the HZMB, with a focus on the new technologies involved in building the artificial islands and immersed tunnel. 展开更多
关键词 BRIDGE marine TUNNEL EAST HAS was is it
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Fishery biology of whitespotted conger Conger myriaster (Brevoort, 1856) in the Yellow Sea and East China Sea 预览
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作者 Xiuxia Mu Chi Zhang +3 位作者 Ying Xue Chongliang Zhang Binduo Xu Yiping Ren 《海洋学报:英文版》 SCIE CAS CSCD 2019年第6期18-24,共7页
Whitespotted conger Conger myriaster is a commercially important species in the seas around China, Korea and Japan. The coastal waters of China serve as an important feeding ground for congers, but the spatio-temporal... Whitespotted conger Conger myriaster is a commercially important species in the seas around China, Korea and Japan. The coastal waters of China serve as an important feeding ground for congers, but the spatio-temporal variations in the fishery and biological characteristics of the population have been rarely evaluated and less well understood in this area. We studied the growth, spawning and feeding characteristics of C. myriaster on the basis of samples collected from October 2016 to April 2017 in the Yellow Sea and East China Sea. A total of 529 specimens were collected, with ages ranging from 1 to 6 years and total length ranging from 132 mm to 834 mm. The parameters of von Bertalanffy growth equation L∞ and k were 1 026 mm and 0.226 a^–1, respectively;the sex ratio was 88:0 (female: male) in the East China Sea and 2.67:1 in the South Yellow Sea;the development stage of ovary ranged from peri-nucleolus stage to secondary yolk globule stage, and the testis of two males was at midmeiotic stage;Crustacean was the major prey for conger of small length, and food source shift to fish with somatic growth. The results showed substantial differences from previous studies in Japan and Korean waters, as well as from China seas in the 1980s, suggesting potential spatiotemporal changes in the biological characteristics of C. myriaster. This study may improve current understanding of the fishery biology of C. myriaster in the Yellow Sea and East China Sea. 展开更多
关键词 Conger myrisater age and growth GONAD development STOMACH contents YELLOW SEA and EAST China SEA
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Zircon U-Pb chronology, geochemistry and Lu-Hf isotope constraints on genesis of monzonitic granite from Harizha area in eastern section of East Kunlun region 预览
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作者 LI Qing CUI Bo +4 位作者 WANG Li PENG Bo ZHANG Yong JIN Ye YIN Yue 《世界地质:英文版》 2019年第1期36-49,共14页
The Harizha area is located in the eastern section of East Kunlun orogenic belt. The petrology, the zircon LA-ICP-MS U-Pb chronology and the petrogeochemistry of the monzonitic granite in the area were studied. The re... The Harizha area is located in the eastern section of East Kunlun orogenic belt. The petrology, the zircon LA-ICP-MS U-Pb chronology and the petrogeochemistry of the monzonitic granite in the area were studied. The results show that the formation age of the monzonitic granite in the Harizha area is 237.4±1.4 Ma, which belongs to Middle Triassic. The content of SiO2 in the rock is 61.29%--63.30%,(K2O+Na2O) is 5.41%--5.84%, Al2O3 is 14.80%--15.99%, the Mg# value is 46.33--48.33, and the aluminum saturation index A/CNK is 0.87--0.91. Therefore, it can be concluded that the rock belongs to the I-type granite of quasi-aluminous high potassium Ca-alkaline series. The total REE content of the rock is 118.82×10-6--164.54×10-6, and the La/Yb ratios range from 7.77 to 10.13. Meanwhile, the rock does not show obvious Eu anomalies(δEu=0.61--0.75) and is characterized by enrichment of LREE and LILE such as Rb and K, relative depletion of HREE and HFSE such as Nb, Ti and Ta. Zircon Hf isotopic dating exhibits that the average εHf(t) is-2.4 and the average of two-stage model age(tDM2) is 1 417 Ma, indicating that the source rocks are mainly crustal materials. It can be concluded from research findings and regional geological structural analysis that the monzonitic granite in the Harizha area originated from partial melting of the Mesoproterozoic mafic lower crust in the later stage of the subduction of the Paleo-Tethys Ocean. 展开更多
关键词 GEOCHEMISTRY U-Pb dating LU-HF ISOTOPES Middle TRIASSIC East KUNLUN OROGENIC belt
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Keeping the Peace
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作者 Godfrey Olukya 《中国与非洲:英文版》 2019年第1期32-33,共2页
When Uganda sent its troops to Somalia to keep peace in the war-torn country in East Africa in March 2007,many locals considered the move would backfire miserably. But the Ugandan armed forces proved their critics wro... When Uganda sent its troops to Somalia to keep peace in the war-torn country in East Africa in March 2007,many locals considered the move would backfire miserably. But the Ugandan armed forces proved their critics wrong and showed their mettie,going on to successfully execute peacekeeping missions not only in Somalia,but also in other countries in the region. 展开更多
关键词 Uganda sent EAST AFRICA CRITICS WRONG
The East Asian Monsoon since the Last Glacial Maximum:Evidence from geological records in northern China
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作者 Shiling YANG Xinxin DONG Jule XIAO 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第8期1181-1192,共12页
The impact of global warming on the climate of northern China has been investigated intensively, and the behavior of the East Asian monsoon during previous intervals of climatic warming may provide insight into future... The impact of global warming on the climate of northern China has been investigated intensively, and the behavior of the East Asian monsoon during previous intervals of climatic warming may provide insight into future changes. In this study, we use paleovegetation records from loess and lake sediments in the marginal zone of the East Asian summer monsoon(EASM) to reconstruct the EASM during the interval of warming from the Last Glacial Maximum(LGM) to the Holocene. The results show that during the LGM, desert steppe or dry steppe dominated much of northern China;in addition, the southeastern margin of the deserts east of the Helan Mountains had a distribution similar to that of the present-day, or was located slightly further south, due to the cold and dry climate caused by a strengthened East Asian winter monsoon(EAWM) and weakened EASM. During the last deglaciation, with the strengthening of the EASM and concomitant weakening of the EAWM, northern China gradually became humid. However, this trend was interrupted by abrupt cooling during the Heinrich 1(H1) and Younger Dryas(YD) events. The EASM intensified substantially during the Holocene, and the monsoon rain belt migrated at least 300 km northwestwards, which led to the substantial shrinking of the desert area in the central and eastern part of northern China, and to the large expansion of plants favored by warm and humid conditions. Paleoclimatic records from the marginal zone of the EASM all show that the EASM reached its peak in the mid-Holocene, and past global climatic warming significantly strengthened the EASM, thereby greatly improving the ecological environment in northern China. Thus, northern China is expected to become wetter as global warming continues. Finally, high resolution Holocene vegetation records are sparse compared with the numerous records on the orbital timescale, and there is a need for more studies of Holocene climatic variability on the centennial-to-decadal scale. 展开更多
关键词 East Asian monsoon Last GLACIAL Maximum HOLOCENE PALEOVEGETATION Global WARMING
国内外新能源开发资料选登 预览
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作者 本刊编辑部 《水电与新能源》 2019年第6期79-80,共2页
核聚变发电 中国进步迅速中国科学家建造的一座突破性核聚变反应堆凸显北京方面决心成为清洁能源技术的核心。它希望到2050年建成一座功能齐全的核聚变发电站。由于产生的热量和能量,位于中国安徽的先进实验超导托卡马克实验装置(简称“... 核聚变发电 中国进步迅速中国科学家建造的一座突破性核聚变反应堆凸显北京方面决心成为清洁能源技术的核心。它希望到2050年建成一座功能齐全的核聚变发电站。由于产生的热量和能量,位于中国安徽的先进实验超导托卡马克实验装置(简称“EAST”)有时被称为“人工太阳”。它已拿下一连串“第一”。 展开更多
关键词 新能源开发 托卡马克实验装置 中国科学家 核聚变发电 清洁能源技术 核聚变反应堆 EAST 发电站
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扭转思维,提升国际科技治理话语权和领导力 预览
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作者 张悦悦 何光喜 张文霞 《科技中国》 2019年第2期31-34,共4页
2018年底,南方科技大学副教授贺建奎基因编辑婴儿事件引发世界舆论关注。回顾我国生命科学领域发展历程,这类事件并非单独个案。从2001年中国研发出世界首例人兔嵌合体引发国际争议、西方媒体给中国科技界冠以“野蛮东方”(Wild East)恶... 2018年底,南方科技大学副教授贺建奎基因编辑婴儿事件引发世界舆论关注。回顾我国生命科学领域发展历程,这类事件并非单独个案。从2001年中国研发出世界首例人兔嵌合体引发国际争议、西方媒体给中国科技界冠以“野蛮东方”(Wild East)恶名,到近年来干细胞试验治疗、免疫细胞治疗乱象在中国屡禁不止,我国科技界每隔几年就爆出一件类似的“冷门”事件(如2012年黄金大米事件、2015年黄军就事件、2016年魏则西事件、2017年“换头手术”事件)。有国际期刊指出,中国科研以“快”著名,却缺乏相匹配的社会伦理约束,“先做事、后讨论”的模式让中国速度令人担忧。 展开更多
关键词 科技界 话语权 扭转 治理 细胞治疗 基因编辑 生命科学 EAST
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