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Studies of Soil Physical Properties and Community Characteristics of Different Abandoned Lands in the Minqin Oasis,Downstream of the Shiyang River
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作者 郭春秀 何芳兰 +6 位作者 马剑平 安富博 马俊梅 袁宏波 赵鹏 刘克彪 申国峰 《Agricultural Science & Technology》 CAS 2016年第7期1697-1701,共5页
[Objective] The aim was to explore physical properties and community characteristics of abandoned lands in different years in Minqin Oasis, downstream of the Shiyang River, [Method] The evolution of environment and pl... [Objective] The aim was to explore physical properties and community characteristics of abandoned lands in different years in Minqin Oasis, downstream of the Shiyang River, [Method] The evolution of environment and plant community characteristics in different abandoned lands were analyzed after abandonment for 1, 2, 3, 4, 5, 8, 15, 24 and 31 years, and the plant community characteristics, water content, bulk density, porosity and mechanical composition of soil in the different a- bandoned lands were also researched in the Minqin Oasis, downstream of the Shiyang River. [Result] Plant of 32 species spread over 14 family live through fifty years appeared in abandoned lands in the study area. Shrubs was 6 species, herbs was 26 species among them, which were 18.75%, 81.25% respectively. The goose- foot family (6 species), the composite family(4 species),the grass family(4 species), caltrop family(3 species) were 53.13% among them. Within the range of 0-40 cm of different abandoned Land, the soil moisture content showed a trend of first increase and then decrease with the increase of soil depth changes in soil bulk density and porosity of less obvious. In the range of 0-40 cm soil depth, the largest proportion of fine sand, followed by silt and clay and the smallest proportion of coarse sand in every plot, but the proportion of the each silt size varies little with the years aban- doned. [Conclusion] The research provides references for vegetation reconstruction and eco-environment construction in abandoned lands in downstream of Shiyang River. 展开更多
关键词 Minqin Oasis Abandoned land Years abandoned Soil physical proper- ties Vegetation characteristics
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Critical role of risk management in ground engineering and opportunities for improvement 被引量:2
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作者 Jim Galvin 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第5期725-731,共7页
Green mining is concerned with mining in a sustainable manner, such that the needs of the present are met without compromising future generations. The achievement of this objective depends on balancing social, environ... Green mining is concerned with mining in a sustainable manner, such that the needs of the present are met without compromising future generations. The achievement of this objective depends on balancing social, environmental and economic objectives and has to have regard to both active mining operations and legacy issues associated with mine closure. Ground engineering has a critical role in achieving green mining objectives but its contribution is characterised by pervasive uncertainty. Uncertainty equates to risk. This means that ground engineering should be practiced within a risk management framework that aims to both prevent unwanted outcomes and to mitigate their consequences to an acceptable level. This keynote address presents the fundamentals of risk management and demonstrates its effectiveness by reference to improvements in the safety performance of the NSW coal sector over the past three decades.Nevertheless, ground control remains a mix of art and science, relying heavily on judgements which should be premised on knowledge, skill and experience(that is, competence). Risk management has now been enshrined in mining legislation and operating practice in Australia for over two decades.Notwithstanding this, near-hit and accident and incident investigations, commissions of inquiry and legal proceedings almost invariably identify deficiencies and opportunities for improvements necessary to achieve the objectives of sustainable mining. Three of the more important opportunities which have global application in relation to ground engineering are discussed. These relate to the vexing issue of defining competency in ground engineering; the criteria for undertaking rigorous risk assessment; and the need for ground engineers to become involved in mine rehabilitation and closure planning over the full life cycle of a mine, commencing at the prefeasibility stage. 展开更多
关键词 BOW tie analysis MINE safety MINE CLOSURE RISK assessment RISK management Sustainable mining Uncertainty
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益母草注射液通过其生物碱成分上调Tie-2、VEGFR2和VEGF促进斑马鱼血管新生
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作者 李玉芝 宋肖敏婷 +4 位作者 王雯雯 周欣雨 黎娅琳 任吉霞 曹治兴 《聊城大学学报(自然科学版)》 2024年第1期85-91,共7页
目的:研究益母草注射液在斑马鱼血管损伤模型中的促血管生成作用,并阐明潜在的物质基础和分子机制。方法:采用HPLC-PAD和TLC技术检测益母草注射液的主要成分;利用舒尼替尼诱导转基因Tg(flk1:eGFP)斑马鱼血管损伤模型,益母草注射液干预... 目的:研究益母草注射液在斑马鱼血管损伤模型中的促血管生成作用,并阐明潜在的物质基础和分子机制。方法:采用HPLC-PAD和TLC技术检测益母草注射液的主要成分;利用舒尼替尼诱导转基因Tg(flk1:eGFP)斑马鱼血管损伤模型,益母草注射液干预治疗后,测量斑马鱼节间血管(ISVs)长度,QT-PCR检测血管生成相关基因的表达水平。结果:发现益母草注射液的主要成分是水苏碱、胆碱和葫芦巴碱;其中,益母草注射液、葫芦巴碱和胆碱可减轻化学诱导的斑马鱼血管损伤,其作用机制涉及益母草注射液上调Tie-2、VEGF和VEGFR2的表达,其主要成分葫芦巴碱上调Tie-2和VEGF的表达,胆碱上调VEGF和VEGFR2的表达。结论:益母草注射液及其主要生物碱成分可通过上调Tie-2、VEGFR2和VEGF来促进血管生成。 展开更多
关键词 益母草注射液 血管生成 葫芦巴碱 胆碱 tie-2 VEGFR2 VEGF
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Effects of anti-pull ties on the bearing behaviors of shallow tunnel-type anchorages in soft rock 被引量:1
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作者 HAN Ya-feng LIU Xin-rong +5 位作者 ABI Erdi TU Yi-liang XU Bin ZHOU Xiao-han DENG Zhi-yun WANG Zhong-hao 《Journal of Mountain Science》 SCIE CSCD 2023年第9期2708-2730,共23页
Tunnel-type anchorages(TTAs)installed in human gathering areas are characterized by a shallow burial depth,and in many instances,they utilize soft rock as the bearing stratum.However,the stability control measures and... Tunnel-type anchorages(TTAs)installed in human gathering areas are characterized by a shallow burial depth,and in many instances,they utilize soft rock as the bearing stratum.However,the stability control measures and the principle of shallow TTAs in soft rock have not been fully studied.Hence,a structure suitable for improving the stability of shallow TTAs in soft rock strata,named the anti-pull tie(APT),was added to the floor of the back face.Physical tests and numerical models were established to study the influence of the APT on the load transfer of TTAs,the mechanical response of the surrounding rock,the stress distribution of the interface,and the failure model.The mechanical characteristics of APTs were also studied.The results show that the ultimate bearing capacity of TTAs with an APT is increased by approximately 11.8%,as compared to the TTAs without an APT.Also,the bearing capacity of TTAs increases approximately linearly with increasing height,width,length,and quantity of APTs,and decreases approximately linearly with increasing distance from the back face and slope angle of the tie slope.The normal squeezing between the tie slope and the surrounding rock increases the shear resistance of the interface and expands the range of the surrounding rock participating in bearing sharing.Both tension and compression zones exist in the APT during loading.The tension zone extends from the tie toe to the tie bottom along the tie slope.The range of the tie body tension zone constantly expands to the deep part of the APT with an increasing load.The peak tensile stress value is located at the tie toe.The distribution of compressive stress in the tie body is the largest at the tie top,followed by the tie slope,and then the tie bottom. 展开更多
关键词 Shallow tunnel-type anchorage Soft rock Anti-pull tie Bearing behaviors Stability control measures
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Firm review revelation policy considering social ties among consumers 被引量:1
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作者 Liu Xueyu Mei Shu'e Zhong Weijun 《Journal of Southeast University(English Edition)》 EI CAS 2021年第1期98-103,共6页
An optimization model is proposed to analyze the optimal review revelation policies and consumer online social network management strategies of e-commerce firms.The results show that displaying friend reviews to consu... An optimization model is proposed to analyze the optimal review revelation policies and consumer online social network management strategies of e-commerce firms.The results show that displaying friend reviews to consumers does not necessarily increase firms profits.Only when positive reviews account for a large proportion of all the reviews and when the cost of showing friend reviews is not high,can showing friend reviews be more profitable than not showing such information.The distribution of social ties among consumers can affect firms profits.Even in the case that showing friend reviews to consumers is more profitable,an increase in the proportion of strong ties is not necessarily beneficial to firms.Only when the proportion of positive reviews is large enough,can firms profits increase with the increase in the proportion of strong ties among consumers.Moreover,the degree of consumer distrust in the average quality rating can also affect firms strategies for managing consumer online social networks.As the degree of consumer distrust in the average quality rating rises,firms are more likely to obtain higher profits by taking measures to increase the proportion of strong ties among consumers on their websites. 展开更多
关键词 online product review social tie review revelation policy social commerce
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脓毒症诊治中Ang/Tie信号通路的研究进展
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作者 杨航 戴菁 王学锋 《诊断学理论与实践》 2024年第1期90-95,共6页
脓毒症以及伴随的多器官功能障碍是一组常见的临床综合征,其患病率随着人口老龄化逐年上升。全球每年发生2000万例脓毒症,死亡率为26%。早期准确诊断脓毒症,有利于及时采取针对性的治疗策略,这是降低病死率的关键。内皮细胞是外源病原... 脓毒症以及伴随的多器官功能障碍是一组常见的临床综合征,其患病率随着人口老龄化逐年上升。全球每年发生2000万例脓毒症,死亡率为26%。早期准确诊断脓毒症,有利于及时采取针对性的治疗策略,这是降低病死率的关键。内皮细胞是外源病原体或内源性损伤信号的早期作用对象。研究提示,内皮细胞的结构改变与功能活化在脓毒症的发生、发展中发挥重要作用。作为内皮细胞专属信号通路,血管生成素(angiopoietin,Ang)/酪氨酸激酶受体(tyrosine kinase receptor,Tie)在内皮细胞的异常激活和损伤中发挥重要作用。Ang/Tie信号通路主要包括2种位于内皮细胞中的酪氨酸激酶受体(Tie1、Tie2)和4种分泌性糖蛋白配体(Ang-1、Ang-2、Ang-3、Ang-4)。机制研究方面,Ang-1可持续性激活Tie2受体,维持细胞与细胞、细胞与基质间的相互作用,支持血管内皮细胞正常的生理功能;Ang-2是Ang-1拮抗剂,可竞争性阻断Ang-1与Tie2受体结合。脓毒症环境下,Ang-1下降,Ang-2升高,Ang-1/Ang-2的比值下降。Ang-2竞争性阻断Ang-1与可溶性Tie2受体结合,内皮细胞处于严重异常激活状态。Ang-2介导肝素酶的释放导致糖萼损伤,可引起血管通透性增加;Ang-2可促进炎症反应;Ang/Tie信号系统失调介导凝血功能障碍,Ang-2升高是弥散性血管内凝血的前哨性事件。临床病情监测方面,Ang-2>5.61 ng/mL,诊断脓毒症的灵敏度为74.36%;Ang-2持续升高,提示内皮功能难以恢复,器官发生功能性改变。早期动态监测Ang-2可用于预测脓毒症相关肺损伤、急性肾损伤。Ang-2/Ang-1比值上升、Ang1/可溶性Tie2比值下降可预测脓毒症患者90 d病死率(ROC曲线面积分别为0.787和0.704)。Ang-2和可溶性Tie-2水平下降,则提示脓毒症血浆置换有效。靶向Ang/Tie信号通路的动物实验获得一定成功,但目前临床试验未能获得有价值的结果。脓毒症相关Ang/Tie信号通路有待于进一步深入研究。 展开更多
关键词 脓毒症 血管生成素 酪氨酸激酶受体Ang/tie
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Still Water Runs Deep:On Practices of Innovative Development in People-to-People Diplomacy of Henan 被引量:1
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作者 Song Liping 《International Understanding》 2017年第2期51-54,共4页
In recent years,Henan sticks to the points of General Secretary Xi Jinping,makes full use of its rich resources and relations,makes efforts to deepen friendship with people around the world,promotes relations with for... In recent years,Henan sticks to the points of General Secretary Xi Jinping,makes full use of its rich resources and relations,makes efforts to deepen friendship with people around the world,promotes relations with foreign countries,pushes 展开更多
关键词 of In OVER AS with on in Still Water Runs Deep:On Practices of Innovative Development in people-to-people Diplomacy of Henan
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调控Ang/Tie信号通路治疗眼底新生血管性疾病的研究进展
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作者 杨婧研(综述) 魏文斌(审校) 《中华实验眼科杂志》 CAS CSCD 北大核心 2024年第5期467-472,共6页
抗血管内皮生长因子(VEGF)治疗应用于眼底新生血管疾病领域以来,在提高视力、稳定疾病病变和在某些情况下逆转疾病方面显示了卓越的效果。但抗VEGF治疗需要频繁玻璃体内注射给药,患者治疗负担重,长期疗效受影响。前期临床研究发现,调控... 抗血管内皮生长因子(VEGF)治疗应用于眼底新生血管疾病领域以来,在提高视力、稳定疾病病变和在某些情况下逆转疾病方面显示了卓越的效果。但抗VEGF治疗需要频繁玻璃体内注射给药,患者治疗负担重,长期疗效受影响。前期临床研究发现,调控血管生成素(Ang)/含免疫球蛋白样环和上皮生长因子样域酪氨酸激酶(Tie)通路在眼底新生血管疾病的治疗中有较好的效果。目前已发布了3个Ang/Tie通路阻断药物治疗眼底新生血管疾病的临床研究数据,其中靶向VEGF-A和Ang-2的双特异性免疫球蛋白G1抗体faricimab进入了Ⅲ期临床试验并达到终点,faricimab的2种延长治疗间隔(12周和16周)的给药方案均被证实有效。本文基于已发表的研究报告,就调控Ang/Tie通路在眼底新生血管性疾病治疗中的作用及临床应用作一综述,总结分析Ang/Tie通路的作用机制以及未来药物的应用前景。 展开更多
关键词 眼底新生血管疾病 抗新生血管生成 Ang/tie通路
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Measurement of vibration frequencies of ties in masonry arches by means of a robotic total station
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作者 Marco Gatti 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第2期489-500,共12页
Measurement of the vibration frequencies of eight ties set in masonry arches of a church by means of a robotic total station is described.The instrument made continuous recordings(up to ten per second)of the three-dim... Measurement of the vibration frequencies of eight ties set in masonry arches of a church by means of a robotic total station is described.The instrument made continuous recordings(up to ten per second)of the three-dimensional positions of a reflector situated at 1/2 or 1/4 of the length of the tie during vertical oscillation induced by an impulsive load.The recording slips,vibration amplitudes(and their accuracy),hourly diagram and experimental spectra of vibrations,and the corresponding frequencies were calculated.The results were verified by comparing them with the vibration frequencies and indirectly the tension and fixed support constraint calculated from accelerometric measurements.The study provides interesting information on the accuracies of the reflector′s three-dimensional coordinates,but highlighted certain limits in the application of robotized total stations for measuring vibration frequencies of ties in masonry arches. 展开更多
关键词 RTS FREQUENCY vibrations ties ARCHES
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Fulbright Program: A Bright Facet of Sino-U.S. People-to-People Exchange
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作者 李晓晗 《海外英语》 2015年第19期169-172,共4页
In the history of Chinese-American people-to-people exchange,the implementation of the China-U.S.Fulbright Program is surely a bright facet which should not be ignored.This program has been cultivating talents in the ... In the history of Chinese-American people-to-people exchange,the implementation of the China-U.S.Fulbright Program is surely a bright facet which should not be ignored.This program has been cultivating talents in the fields of social sciences and humanities for the two countries,promoting Sino-U.S.communications in the domains of education,academia and culture,and propelling the diffusion and advance of both Chinese and American cultures.The Fulbright Program in China still has certain limitations waiting to be improved,and one obvious problem is its coverage in China.To solve this problem,more Chinese higher education institutions should be included in the China-U.S.Fulbright Program,and the result would be the generation of immeasurable value for the prosperity of Sino-American people-to-people exchange and therefore the construction of the new model of major country relations between China and the United States. 展开更多
关键词 The China-U S FULBRIGHT PROGRAM Sino-U people-to-people EXCHANGE James William FULBRIGHT talent CULT
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Extension of Switching Costs Antecedents Based on Customers' Social Ties
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作者 SHI Wenhua JI Chen +2 位作者 LI Xiaowen TANG Lingshu LV Tingjie 《China Communications》 SCIE CSCD 2014年第1期152-163,共12页
The effects of customers' social ties on switching costs have recently attracted researchers' attention.This study formally included customers' social ties as a new antecedent to supplement those elucidate... The effects of customers' social ties on switching costs have recently attracted researchers' attention.This study formally included customers' social ties as a new antecedent to supplement those elucidated by Burnham in 2003.Through empirical research,this study successfully verified the reliability and validity of items created to measure social ties,and it demonstrated the facilitating effects of social ties as an antecedent on customers' procedural and relational switching costs.Finally,the study lists managerial implications aimed at retaining customers through knowledge of this added antecedent. 展开更多
关键词 Switching costs ANTECEDENT social ties
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Post-Sept. -11 Sino-U. S. Ties
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作者 Yuan Peng Yuan Peng is Associate Research Professor and Deputy Director at Division for North and Latin American Studies, China Institute of Contemporary International Relations. 《Contemporary International Relations》 2001年第11期1-16,共16页
Like a big rock thrown into the pond of current international power configuration, the event of September 11 revealed the turbulent undercurrents beneath its seemingly tranquil surface. The splashdown effect has sprea... Like a big rock thrown into the pond of current international power configuration, the event of September 11 revealed the turbulent undercurrents beneath its seemingly tranquil surface. The splashdown effect has spread beyond the United States to reach every corner of our planet. It has triggered realignment in big power relations and will have its far- 展开更多
关键词 ties Post-Sept Sino-U
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The Sign Test with Ties Included
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作者 Jennings B. Marshall 《Applied Mathematics》 2014年第10期1594-1597,共4页
The sign rank test is taught in virtually all introductory Statistics classes. When teaching the sign rank test the students are told to ignore the ties. Ignoring ties that support the null hypothesis is not logical. ... The sign rank test is taught in virtually all introductory Statistics classes. When teaching the sign rank test the students are told to ignore the ties. Ignoring ties that support the null hypothesis is not logical. Why should valid data that support the null hypothesis be ignored? The approach taken here demonstrates a method for testing with ties included. A typical problem presentation in a text book would indicate that if you had ten ties in a sample of size fifty the tie scores would be excluded. However, the ten tie scores are a very valuable piece of statistical information which should not be ignored. The method demonstrated here shows that a different conclusion is reached in some cases when the ties are not excluded. Further many sign tests often will have ties because in some cases the data are not a cardinal number, but an ordinal number chosen from a set often results in ties. The alternative approach uses a one-tailed distribution and considers both +’s and -'s separated. A two-tailed test for equal variances is done with a one-tail of an F distribution. This alternate approach to the sign test allows the use of important statistical information which has been ignored with the traditional sign rank test. 展开更多
关键词 SIGN TEST ties
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Chinese,Portuguese Leaders Exchange Congratulations on 40th Anniversary of Diplomatic Ties
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《China Today》 2019年第3期6-6,共1页
Chinese President Xi Jinping and Portuguese President Marcelo Rebelo de Sousa on February 8 exchanged congratulations on the 40th anniversary of the establishment of China-Portugal diplomatic relations.
关键词 The establishment of diplomatic ties CHINESE PORTUGAL
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The Principle Describing Possible Combinations ofSingularities in Deformations of a Fixed Singularity
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作者 Tohsuke URABE 《Chinese Quarterly Journal of Mathematics》 CSCD 1995年第4期98-104,共7页
ThePrincipleDescribingPossibleCombinationsofSingularitiesinDeformationsofaFixedSingularity¥TohsukeURABE(Depa... ThePrincipleDescribingPossibleCombinationsofSingularitiesinDeformationsofaFixedSingularity¥TohsukeURABE(DepartmentofMathemati... 展开更多
关键词 Dynkin graph elementary transformation tie transformation
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Ponder over the Changes in Sino-Russian-U. S. Ties
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作者 Xing Guangcheng 《Contemporary International Relations》 2003年第6期8-12,共5页
Some changes have indeed taken place in international situation from September 11 to Iraq war. Changes in big power relations in particular have given food for thought. Today Ⅰ would like to focus on the changes in t... Some changes have indeed taken place in international situation from September 11 to Iraq war. Changes in big power relations in particular have given food for thought. Today Ⅰ would like to focus on the changes in the relations among China, Russia and the United States as well as my consideration of China’s diplomacy. 展开更多
关键词 in on ties Ponder over the Changes in Sino-Russian-U OVER
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The US Enhancing Ties with Sri Lanka: Motivations and Restraints
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作者 Li Yibo 《China International Studies》 2019年第4期98-112,共15页
The rapid growth in US-Sri Lanka relations is the latest attempt by the US to implement its Indo-Pacific strategy in South Asia. As the strategy materializes, the intensified US involvement in the region will bring ne... The rapid growth in US-Sri Lanka relations is the latest attempt by the US to implement its Indo-Pacific strategy in South Asia. As the strategy materializes, the intensified US involvement in the region will bring new variables to the security situation in the Bay of Bengal and the Indian Ocean. 展开更多
关键词 The US ENHANCING ties SRI Lanka MOTIVATIONS and RESTRAINTS
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Xi Meets European Leaders on Advancing Ties, Global Governance
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《China Today》 2019年第5期6-6,共1页
Chinese President Xi Jinping, French President Emmanuel Macron, German Chancellor Angela Merkel and European Commission President Jean- Claude Juncker met in Paris on March 26 and agreed to strengthen China-European U... Chinese President Xi Jinping, French President Emmanuel Macron, German Chancellor Angela Merkel and European Commission President Jean- Claude Juncker met in Paris on March 26 and agreed to strengthen China-European Union (EU) relations and global governance cooperation. 展开更多
关键词 XI Meets EUROPEAN LEADERS Advancing ties
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People-to-People Connectivity is the Key Foundation for the Implementation of the Belt and Road Initiative
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作者 Jin Xin Duan Jing 《International Understanding》 2018年第4期35-38,共4页
Since it was put forward more than five years ago,the Belt and Road Initiative has become a grand business card of a new round of opening up of China,leading the sound development of economic globalization and promoti... Since it was put forward more than five years ago,the Belt and Road Initiative has become a grand business card of a new round of opening up of China,leading the sound development of economic globalization and promoting the building of a community with a shared future for mankind.Over the past five years,the work that facilitates people-to-people connectivity has been carried out in a solid manner. 展开更多
关键词 people-to-people CONNECTIVITY the BELT and ROAD
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China's WTO Entry Helps Sino-US Ties
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作者 蒋裕国 《Contemporary International Relations》 2000年第9期1-10,共10页
China applied for restoration of its status as the GATT founding member in1986. The country has made great endeavor in reducing customs duties, removing non-tariff barriers, enhancing protection of intellectual proper... China applied for restoration of its status as the GATT founding member in1986. The country has made great endeavor in reducing customs duties, removing non-tariff barriers, enhancing protection of intellectual property rights andservice trades, launching reform of the foreign trade regime, eliminating trade bar-riers and improving environment for foreign investment. Over the past 14 years,China has taken part in 26 relevant multilateral meetings and hundreds of bilateralnegotiations. 展开更多
关键词 WTO WILL China’s WTO Entry Helps Sino-US ties US
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