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Anti-Poverty Cooperation between China and West Asian and North African Countries in the Context of the Belt and Road Initiative
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作者 Xiaoxing WANG 《Asian Agricultural Research》 2018年第12期1-5,9,共6页
As important parts of the Belt and Road Initiative,West Asia and North Africa have rich resources and prominent strategic position.Anti-poverty has always been a crucial social issue of China,West Asia and North Afric... As important parts of the Belt and Road Initiative,West Asia and North Africa have rich resources and prominent strategic position.Anti-poverty has always been a crucial social issue of China,West Asia and North Africa. Through literature review and data analysis,this paper analyzed the current situations of anti-poverty in West Asia and North Africa and the causes of poverty,and objectively summarized the realistic foundation of anti-poverty cooperation between China and West Asian and North African countries. On the basis of current situations,it put forward a path for anti-poverty cooperation between China and West Asian and North African countries,in the hope of providing decisionmaking basis and policy recommendations for China to undertake anti-poverty cooperation in the worldwide range. 展开更多
关键词 the BELT and Road INITIATIVE China WEST asia and NORTH africa ANTI-POVERTY COOPERATION
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A Friendly Visit across Europe,Asia and Africa:Sidelights on the Visit of H.E.Ji Bingxuan to the Republic of Congo,Portugal and Tanzania
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作者 Jin Yan 《International Understanding》 2019年第3期5-9,共5页
The visit to three countries took 10 days and nights via 8 flights. From 11 to 20 December, a fifteen-member delegation led by H.E. Ji Bingxuan, Deputy Chairman, Standing Committee of National People’s Congress and P... The visit to three countries took 10 days and nights via 8 flights. From 11 to 20 December, a fifteen-member delegation led by H.E. Ji Bingxuan, Deputy Chairman, Standing Committee of National People’s Congress and President of the Chinese Association for International Understanding(CAFIU) visited the Republic of Congo,Portugal and Tanzania. 展开更多
关键词 A Friendly VISIT ACROSS EUROPE asia and africa Sidelights on the VISIT PORTUGAL and Tanzania
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Near-infrared reflectance spectroscopy reveals wide variation in major components of sesame seeds from Africa and Asia 被引量:10
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作者 Komivi Dossa Xin Wei +7 位作者 Marème Niang Pan Liu Yanxin Zhang Linhai Wang Boshou Liao Ndiaga Cissé Xiurong Zhang Diaga Diouf 《The Crop Journal》 SCIE CAS CSCD 2018年第2期202-206,共5页
Sesame is an important oilseed crop in Africa and Asia, owing to its high nutritional quality seed and market value. Variation in sesame seed components including oil, oleic acid,linoleic acid, and protein was investi... Sesame is an important oilseed crop in Africa and Asia, owing to its high nutritional quality seed and market value. Variation in sesame seed components including oil, oleic acid,linoleic acid, and protein was investigated by near-infrared reflectance spectrometry in 139 samples collected from different countries. Oil and protein contents were between 40.8%and 60.3%(mean 53.0%) and 15.5% to 25.5%(mean 20.4%), respectively. Linoleic acid,ranging from 31.8% to 52.4%(mean 46%) was more abundant than oleic acid(31.8%–50.6%,mean 38.1%). Light-seeded samples displayed higher nutritional quality, as they were richer in oil, protein, and linoleic acid than dark seeds. Samples from Africa had higher oil and linoleic acid contents, while Asian samples had higher oleic content. The analysis revealed West African sesame cultivars containing especially high levels of seed components, which may command high market values. Two clusters of sesame samples grouped by seed composition were obtained, including one cluster with high oil and oleic acid content and the other with high protein and linoleic acid content. This study revealed that sesame samples from Africa and Asia harbor high variation for major seed components and also provided background information for breeding high-nutrition varieties according to the demands of sesame seed markets. 展开更多
关键词 Sesamum indicum Major SEED components VARIATION asia africa NIRS
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Study of Changing Features of Precipitation from 1900-2010 Years in Africa-Asia Arid and Semi-Arid Area
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作者 Xiangkun Cheng Hang Cheng +1 位作者 Guowu Sun Xiaomeng Shi 《Journal of Geoscience and Environment Protection》 2017年第1期62-72,共11页
The relationship between time-space variation characteristics and the variation of the general atmospheric circulation of rainfall occurred in Asia, Africa through North Africa-Middle East-Western Middle Asia-Eastern ... The relationship between time-space variation characteristics and the variation of the general atmospheric circulation of rainfall occurred in Asia, Africa through North Africa-Middle East-Western Middle Asia-Eastern Middle Asia, Northwest China-Eastern Northwest China-North China and Northeast China is studied based on the analysis of GPCC rainfall data from 1901 to 2010 and annual precipitation in relevant cities of China from 1901 to 2010, and the data of NCEP of surface pressure as well as 500 Hpa potential high from 1950 to 2010. The result shows that the total precipitation presents a decreasing trend in north Africa to the northeast of China in recent 100 years. It has a mutation in 1950s. The precipitation presented a decreasing trend in North Africa and Middle East, in recent 100 years;it presented a further decreasing trend after 1950s. It presented a decreasing trend before 1950s and an increasing trend after 1950s in Middle Asia and Northwest china. It also presented a decreasing trend before 1950s and an increasing trend between 1950s to 1990s, and decreased later in Eastern Northwest China, North China and Northeast China which also presented in a more or less period in different areas from North Africa to Northeast China. The beginning of less precipitation years and less period occurred after it presented less period in north Africa in time and space. After it moved to the east areas as the year past, at last, the SLPA fields which presented more or less precipitations of years from North Africa to Northeast China were analyzed. It also shows that the SLPA fields which presented more were beneficial to the precipitations and presented negative effects of precipitations in the polar, high and mid- and lower latitudes. 展开更多
关键词 asia-africa ARID and SEMI-ARID Region RAINFALL above or below the Normal PRECIPITATION Sea Lever Pressure ANOMALIES
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The Distribution of Petroleum Resources and Characteristics of Main Petroliferous Basins along the Silk Road Economic Belt and the 21st-Century Maritime Silk Road 被引量:3
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作者 HAO Qingqing ZUO Yinhui +3 位作者 LI Lintao CHEN Weijun YI Junjie WU Lei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第4期1457-1486,共30页
The Silk Road Economic Belt and the 21st-Century Maritime Silk Road Initiative, abbreviated as the Belt and Road Initiative, is a primary development strategy of China's future international cooperation. Especially, ... The Silk Road Economic Belt and the 21st-Century Maritime Silk Road Initiative, abbreviated as the Belt and Road Initiative, is a primary development strategy of China's future international cooperation. Especially, the energy resource cooperation, including oil and gas resources cooperation, is an important part of this initiative. The Belt and Road has undergone complicated geological evolution, and contains abundant mineral resources such as oil, gas, coal, uranium, iron, copper, gold and manganese ore resources. Among these, Africa holds 7.8% of the world's total proven oil reserves. The oil and gas resources in Africa are relatively concentrated, with an overall low exploration degree and small consumption demand. Nigeria and Libya contain the most abundant oil resources in Africa, accounting for 2.2% and 2.9% of the world's total reserves, respectively. Nigeria and Algeria hold the richest natural gas resources in Africa, occupying 2.8% and 2.4% of the world's total reserves, respectively. Africa's oil and gas resources are mainly concentrated in Egypt, Sultan and Western Sahara regions in the northern Africa, and the Gulf of Guinea, Niger River and Congo River area in the western Africa. The Russia--Central Asia area holds rich petroleum resources in Russia, Kazakhstan, Turkmenistan and Uzbekistan. The potential oil and gas areas include the West Siberia Basin, East Siberia Basin and sea continental shelf in Russia, the northern and central Caspian Basin in Kazakhstan, the right bank of the Amu-Darya Basin, the East Karakum uplift and the South Caspian Basin in Turkmenistan, and the Amu-Daria Basin, Fergana Basin, Afghan-Tajik Basin and North Ustyurt Basin in Uzbekistan. The Middle East oil and gas resources are mainly distributed in the Zagros foreland basin and Arabian continental margin basin, and the main oil-producing countries include Saudi Arabia, Iran and Iraq. The Asia Pacific region is a new oil and gas consumption center, with rapid growth of oil and gas demand. In 2012, this region consumed about 33.6% of the world's total oil consumption and 18.9% of the world's total natural gas consumption, which has been ranked the world's largest oil and gas consumption center. The oil and gas resources are concentrated in China, Indosinian, Malaysia, Australia and India. The abundant European proven crude oil reserves are in Norway, Britain and Denmark and also rich natural gas resources in Norway, Holland and Britain. Norway and Britain contain about 77.5% of European proven oil reserves, which accounts for only 0.9% of the world's proven reserves. The Europe includes main petroliferous basins of the Voring Basin, Anglo-Dutch Basin, Northwest German Basin, Northeast German-Polish Basin and Carpathian Basin. According to the analysis of source rocks, reservoir rocks, cap rocks and traps for the main petroliferous basins, the potential oil and gas prospecting targets in the Belt and Road are mainly the Zagros Basin and Arabic Platform in the Middle East, the East Barents Sea Basin and the East Siberia Basin in Russia-Central Asia, the Niger Delta Basin, East African rift system and the Australia Northwest Shelf. With the development of oil and gas theory and exploration technology, unconventional petroleum resources will play an increasingly important role in oil and gas industry. 展开更多
关键词 petroliferous basin pay zone africa Middle East Central asia RUSSIA asia Pacific region
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Institutions as Tools of Public Policy: A Comparative Evaluation of South East Asian-Sub-Saharan African Post War Development
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作者 Munetsi Mandere 《Journal of Earth Science and Engineering》 2015年第5期319-332,共14页
In general, it can be argued that institutional framework a country or region designs plays a significant role in crafting, applying or even success of public policy. Drawing lessons from how Asia exploited the develo... In general, it can be argued that institutional framework a country or region designs plays a significant role in crafting, applying or even success of public policy. Drawing lessons from how Asia exploited the developmental state's concept by designing institutions which targeted key public policy areas such as education, health, domestic savings, and rural development, or aligned infrastructures such as roads, transport and ports, to drive economic development. The paper explores how this approach can be applied in sub-Saharan Africa (or individual countries). The objective is to extricate constant factors impacting development both in ahistorical and atemporal terms. The investigation is guided by the key question: whether quality of institutions and institutional analysis can help explain development failures in Africa? Hence, on one part, it probes institutions, institution-making, public policy making and what uniquely the Asian developmental state did that can help illuminate institutional role in policymaking and application. In pursuing this objective, the paper is cognisant of the question by Brousseau et al. asked, regarding generalizability of institutional capabilities, "If growth-enhancing institutions are identified in a specific country, can other countries learn from and transplant these". The investigation concludes that in public policy and development strategy-making institutions do matter as they delimit or even help create possibilities necessary for development and its sustenance, and to a certain extent, they are the vital constant (factors) that explains development differentiations in different geographic spaces or time periods. 展开更多
关键词 DEVELOPMENT developmental state institutions I0 (international organisations) public policy SEA (South East asia SSA (Sub-Saharan africa).
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Politics and the Science of COVID-19;Global Lessons
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作者 Manya Wandefu Stephen Odok Kizito 《Journalism and Mass Communication》 2023年第2期66-70,共5页
Politics is essentially about who gets what,when,and how.It involves realization of power relations and activities for impartial welfare of a populace.The varied human appeals invariably demand that politicians or ins... Politics is essentially about who gets what,when,and how.It involves realization of power relations and activities for impartial welfare of a populace.The varied human appeals invariably demand that politicians or institution advocate for means that meet physical and related needs of the public.Science is distinctly about experiential truths and how these truths distress human lives.It is broadly an intellectual activity about the systematic study of the structure and behavior of the corporeal and the natural world through observation and experiment leading to uncovering germane truths.The correlation between the dual disciplines is consequently symbiotic and relates to the welfare of the populace.This relationship is deepened in times of calamities as well as in times of natural disasters like medical tragedies,famine,draught,and social obliteration.While politics seeks to ameliorate such crisis by seeking short-term remedies for partisan contentment or as long as politicians have power,science demands caution and empirical truths regarding the causes for such misfortunes and proposes scientific solutions to the crisis.These scientific veracities are timeless,meant to provide remedies to such emerging calamities.The contemporary case of COVID-19 has validated how these two fields have either complemented or controverted each other occasioning weighty apprehensions regarding human lives around the globe.This paper is descriptive in nature and seeks to isolate the global lessons learnt since COVID-19 as politics encounters science.It has relied on obtainable and emerging literature regarding the subject. 展开更多
关键词 POLITICS SCIENCE COVID-19 AMERICA EUROPE asia and africa
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Poverty reduction through the development of inclusive food value chains 被引量:3
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作者 Rob VOS Andrea CATTANEO 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第4期964-978,共15页
Propelled by urbanization,rising incomes,and changing diets,food markets have been expanding in Africa and South Asia,creating the vast potential for job and income opportunities along food supply chains and,hence,for... Propelled by urbanization,rising incomes,and changing diets,food markets have been expanding in Africa and South Asia,creating the vast potential for job and income opportunities along food supply chains and,hence,for poverty reduction.The novel coronavirus(COVID-19)that spread to a pandemic in early 2020 provokes enormous setbacks to this expansion.This,however,should provide lessons regarding the importance of resilient and inclusive food systems.Emergency responses to COVID-19 should consider interventions towards that end and leverage the opportunities provided by food markets growth as economies recover from the present economic recession.This paper assesses options of how this could be done by facilitating the better functioning and interconnectedness of the many small and medium-sized enterprises that are proliferating along the"hidden middle"of food value chains in storage,logistics,transportation,and wholesale and retail distribution.It also explores how policies can help smallholder farmers connect to this"hidden middle"in more gainful ways and help them climb out of poverty as well. 展开更多
关键词 POVERTY food security and hunger food supply chains South asia sub-Saharan africa
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China's unique role in the field of global health 被引量:1
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作者 Yang Cheng Feng Cheng 《Global Health Journal》 2019年第4期98-101,共4页
China's participation in global governance,inspired by the 17 United Nations Sustainable Development Goals,is driven by the guiding principle of"Building a Community of Shared Future for Mankind".China h... China's participation in global governance,inspired by the 17 United Nations Sustainable Development Goals,is driven by the guiding principle of"Building a Community of Shared Future for Mankind".China has been promoting the Belt and Road Initiative and South-South Cooperation and has made significant contributions to the prosperity of human beings.Along with the opportunities that globalization brought about such as the World Health Organization and the boom in the economy,global health challenges also emerged.This resulted in certain obstacles for China when it sought to advocate the Belt and Road Initiative and when it attempted to carry out its strategy to address global health issues.What are the emerging challenges for global health?What can China do for global health?Why does global health need China?We tried to address these questions as China's global engagement continues to expand in the new era.This article makes the case for Chinese approaches,including getting involved in public health,being consistent in addressing local conditions,and sharing China's experience with handling health services and staying in the lead through government action while being guided by relative policies.China has a lot to offer in the promotion of global health and in overcoming the challenges and risks that this goal currently faces.Thus,China should be considered an inseparable part of global health governance and bilateral health development cooperation. 展开更多
关键词 China GLOBAL HEALTH africa PROPOSAL asia
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Indian Anti-Malaria OMARIA Is Effective Against African Drug Resistant <i>P. falciparum</i>Field Isolates and Laboratory Strains;without Toxicity
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作者 Jean Bernard Lekana-Douki Deepak Bhattacharya +1 位作者 Rafika Zatra Fousseyni S. Toure-Ndouo 《International Journal of Clinical Medicine》 2012年第1期1-8,共8页
OMARIA which is used to treat malaria in Odisa province, India, was investigated in Africa. The in-vitro anti-malarial activity of OMARIA was tested on P. falciparum strains FCB (chloroquine-resistant) and 3D7 (chloro... OMARIA which is used to treat malaria in Odisa province, India, was investigated in Africa. The in-vitro anti-malarial activity of OMARIA was tested on P. falciparum strains FCB (chloroquine-resistant) and 3D7 (chloroquine-sensitive) and on fresh clinical isolates from Gabon, using the DELI method. Host cell toxicity was analysed with the MTT test. Interesting activity was observed. Inhibition concentrations (IC50) were 20.6 ± 5.2 μg/ml and 14.1 ± 4.3μg/ml respectively on FCB and 3D7 strains. On clinical isolates, the mean of IC50 was 10.65 ± 4.8μg/ml. OMARIA is highly potent against all field isolates tested by us (Gabon includes Pfmdr1 N86). Lethal dose on Vero cells being 165 ± 10.7μg/ml indicate a selective index of 13 for FCB, i.e., non-toxic. Data substantiates scientific rationale for use of OMARIA. This information and such understanding can be used in searching African phyto parables (for use in Africa with similar results as in India) and in new drug design. With Indian assistance, Punica granatum can also be cultivated in Central Africa, and OMARIA can be made, with an aim to Fight Malaria at Home. 展开更多
关键词 Fruit Extracts OMARIA ANTIPLASMODIAL Activity asia-africa Efficacy Cytotoxicity Drug Resistant-Field Isolates PLASMODIUM FALCIPARUM
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The Upheaval in West Asia and North Africa:A Constructed New Viewpoint of World Security
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作者 WU Sike 《Asian Journal of Middle Eastern and Islamic Studies》 2013年第1期1-16,共16页
The Arab political transformations originally occurring in early 2011 are posing negative impact over China’s overseas interests in the Middle East region,including those related to its trade with the Arab world,the ... The Arab political transformations originally occurring in early 2011 are posing negative impact over China’s overseas interests in the Middle East region,including those related to its trade with the Arab world,the China-Middle East bilateral investments,its contracted projects,and the safety of its nationals living in the Middle East,whether these influences are direct or indirect,overt or covert.Three aspects are strongly impacted by these negative influences:1)Libya;2)Northern and southern Sudan;3)Energy supply.The dramatic changes of the Arab world have brought alerting signals to China over its national interests in the Middle East,so China shall undertake a meticulous review of its overseas activities and draw the correct lessons from its experiences there so that practical responses can be worked out.In consideration of the loss that Chinese corporations have suffered from the Arab political changeovers,China should establish its own grand strategy for its foreign relations so as to protect its growing overseas interests. 展开更多
关键词 Dramatic Political Changeovers in West asia and North africa China Overseas Interests New Viewpoint of Security
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2022年欧美以外其他地区中密度纤维板产能概况
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作者 陈怡 《中国人造板》 2024年第9期37-41,共5页
对亚洲、南美洲、大洋洲和非洲地区主要国家中密度纤维板年产能、新增产能情况进行介绍。2022年,亚洲、南美洲、大洋洲和非洲等欧美以外地区,中密度纤维板年产能为8810.7万m^(3),2023年及其后总年产能将达到9474.9万m^(3)。
关键词 中密度纤维板 亚洲 南美洲 大洋洲 非洲 产能
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印日“亚非增长走廊”计划:战略缘起、发展进程、影响要素与应对
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作者 涂志明 《云南行政学院学报》 2024年第4期124-135,148,共13页
作为回应中国“一带一路”倡议的政策,“亚非增长走廊”计划是印度和日本在印度洋—太平洋地区战略调整的结果。在加强双边关系的前提下,两国联合推动亚洲与非洲基础设施的共同开发,并力求将印度的战略触手和日本的经济触手从南亚地区... 作为回应中国“一带一路”倡议的政策,“亚非增长走廊”计划是印度和日本在印度洋—太平洋地区战略调整的结果。在加强双边关系的前提下,两国联合推动亚洲与非洲基础设施的共同开发,并力求将印度的战略触手和日本的经济触手从南亚地区延伸至印度洋—太平洋地区。印、日通过基础设施建设以及其他领域内的合作,谋求通过联合的方式与美国的亚太政策呼应,进而实现对中国的战略包围。两国通过构建共同的地区战略,不仅能够实现与“一带一路”竞争的目标,还能以抱团的形式介入到地缘政治的角逐中。由于印、日在战略认知、对非政策等层面的差异,以及亚非增长走廊计划本身的内在问题,该计划仍然面临诸多不确定性。在此背景下,中国仍需保持战略定力,在推动“一带一路”高质量发展的基础上,强化与相关国家的互利关系,从而有效应对印、日的地区发展规划。 展开更多
关键词 亚非增长走廊 “一带一路” 印度 日本
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West Asia in the Post-Pandemic World Order:Shaping the RIC(Russia-India-China)as an Instrument for Regional Peace 被引量:1
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作者 Talmiz Ahmad 《Asian Journal of Middle Eastern and Islamic Studies》 2020年第3期323-344,共22页
The ongoing COVID-19 pandemic has raised questions about the shape of the world order that will emerge from this crisis.The general view is that it will accelerate trends that were already apparent in world affairs.Th... The ongoing COVID-19 pandemic has raised questions about the shape of the world order that will emerge from this crisis.The general view is that it will accelerate trends that were already apparent in world affairs.The pandemic has hit West Asia with a‘double whammy’-the health crisis coupled with the collapse in oil prices on which most regional economies depend to maintain their political,economic and social order.With the region already enmeshed in serious conflicts-in Syria,Yemen and Libya-and experiencing widespread destruction and instability,there are legitimate concerns that the pandemic could aggravate regional divisions and,by design or inadvertence,plunge West Asia into a region-wide conflagration.Given diminished US capacity,credibility and interest in global leadership and responsibility,this paper argues that the pandemic has opened up opportunities for the exploration of new engagements and alignments and shaping of new leadership roles.The paper proposes that the three RIC nations-Russia,India and China-work jointly in a‘Greater Eurasian Partnership’framework to address their internal,regional and global interests.This will strengthen mutual ties within the trilateral format,particularly through resetting Sino-Indian relations,so that the RIC could become an effective instrument to promote regional security and stability.This revitalised RIC would then be well-equipped to pursue initiatives to deal with West Asia’s immediate pandemic-related challenges and shape and lead a peace process in West Asia. 展开更多
关键词 Post-pandemic world order Covid-19 West asia and North africa asia and the Middle East
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40kaBP来亚非季风演化趋势及青藏高原泛湖期 被引量:16
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作者 贾玉连 施雅风 +2 位作者 马春梅 申洪源 吴敬禄 《地理学报》 EI CSCD 北大核心 2004年第6期829-840,共12页
基于18个黄土/古土壤序列(黄土高原与青藏高原)与27个湖泊沉积序列(青藏高原、新疆、云南与赤道非洲及其以北的非洲季风区)对比分析了东亚季风区、印度季风区与非洲季风区40 ka以来的区域环境演变特征.结果显示:上述区域在对应岁差周期... 基于18个黄土/古土壤序列(黄土高原与青藏高原)与27个湖泊沉积序列(青藏高原、新疆、云南与赤道非洲及其以北的非洲季风区)对比分析了东亚季风区、印度季风区与非洲季风区40 ka以来的区域环境演变特征.结果显示:上述区域在对应岁差周期的高太阳辐射阶段,也就是40~24 kaBP与14~4 kaBP分别经历了一次环境湿润期,而在末次冰期最盛期,除中国云南、青藏高原及新疆部分地区外,其他地区则较为干燥.青藏高原及其北侧的新疆区,40~24 kaBP比14~4 kaBP气候更为湿润,湖泊呈现40 ka以来的最高最大湖面,高原进入一次泛湖期.而非洲区及黄土高原,则与此相反;14~4 kaBP气候比40~24 kaBP更为湿润、适宜,湖面更高,成壤作用更强.40~24 kaBP,印度季风强盛,加强了对高原的水汽与潜热输送,同时,由于北方冰盖的存在,西风气流则相对南移,增加了对高原的影响,两种气流交互作用引起的强降水,可能是造成湖泊显著扩张的主要原因. 展开更多
关键词 青藏高原 印度季风 季风演化 季风区 东亚季风 强降水 岁差周期 BP 新疆 非洲
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全新世期间亚洲和非洲干旱区环境的短尺度变化 被引量:19
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作者 郭正堂 N.Petit-Maire 刘东生 《古地理学报》 CAS CSCD 1999年第1期68-74,共7页
过去对北非和中国干旱区140 ka BP来环境演化的初步对比表明,两地的干旱度在万年时间尺度上基本同步。这种关系是否也适用于全新世百年尺度的干旱事件,仍是有待研究的问题。本文对撒哈拉地区569个地表淡水指示物和我国北方干旱区158个... 过去对北非和中国干旱区140 ka BP来环境演化的初步对比表明,两地的干旱度在万年时间尺度上基本同步。这种关系是否也适用于全新世百年尺度的干旱事件,仍是有待研究的问题。本文对撒哈拉地区569个地表淡水指示物和我国北方干旱区158个古土壤和湖泊沉积的^(14)C年代数据进行了时空频数统计分析,揭示出两地沙漠在全新世期间至少经历了三次同时性的、百年—千年尺度的干旱事件,叠置于季风气候对地球轨道变化响应的总体趋势上;沙漠在纬向上的进退主要受控于季风前沿的伸缩幅度,说明两个季风系统的短尺度变化可能受统一因素控制。最为显著的干旱事件发生于约4 ka BP。两地干旱区在过去认为的6 ka BP前后的全新世气候适宜期并没有表现为稳定的湿润环境。我国过去发现的该时期不少的干旱证据被解释为高温所导致的强烈蒸发作用所致。但全新世中期的干旱期在热带的存在及其与冰心记录中低甲烷事件的吻合难以用蒸发来解释,而应与夏季风环流的减弱有关。 展开更多
关键词 全新世 短尺度变化 亚洲 非洲 季风 干旱化
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地表反照率的改变影响夏季北非副热带高压的数值模拟 被引量:13
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作者 李伟平 吴国雄 刘辉 《气象学报》 CSCD 北大核心 2000年第1期26-39,共14页
利用 LASG L 9R1 5AGCM设计了两组不同地表反照率的数值试验。通过分析其夏季平均气候的差异来考察地表反照率改变对夏季北非副高的影响。结果表明 ,当北非地表反照率增大时 ,由于地面接收到的净辐射减少 ,地面温度降低 ,底层大气的感... 利用 LASG L 9R1 5AGCM设计了两组不同地表反照率的数值试验。通过分析其夏季平均气候的差异来考察地表反照率改变对夏季北非副高的影响。结果表明 ,当北非地表反照率增大时 ,由于地面接收到的净辐射减少 ,地面温度降低 ,底层大气的感热加热减弱 ,抑制了局地的对流和降水 ,相应的对流层中层的凝结加热也减弱。这种中、低层的冷却强迫出高空的异常辐合与低空的异常辐散 ,导致北非地区下沉运动增强 ,从而加强了北非副高。另外 ,这种北非地区的环流异常 ,通过辐散风环流加强了南亚高空的辐散 ,在一定程度上加强了南亚高压。 展开更多
关键词 地表反照率 数值模拟 南亚高压 气压 副热带高压
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发展中国家农业科研投资现状 被引量:11
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作者 王平 杨巍 《中国农业科技导报》 CAS CSCD 2002年第5期74-79,共6页
198 0年以来 ,发展中国家的农业科研投资增长速度和农业科研人员人均科研支出均呈现下降趋势 ;在非洲和拉丁美洲 ,发展中国家的农业科研面临严重资金短缺局面 ,农业科研人员人均科研支出大幅下降 ;非洲发展中国家的农业科研支出占政府... 198 0年以来 ,发展中国家的农业科研投资增长速度和农业科研人员人均科研支出均呈现下降趋势 ;在非洲和拉丁美洲 ,发展中国家的农业科研面临严重资金短缺局面 ,农业科研人员人均科研支出大幅下降 ;非洲发展中国家的农业科研支出占政府财政支出的比重高于其它发展中国家 ;近年来 ,非洲国家的农业科研投资中国际援助资金的比重上升 ,政府财政资助的比重下降 ;拉丁美洲的农业科研投资还是主要以公共部门为主 ;亚洲发展中国家的农业科研投资虽然保持继续增长的势头 ,但增速下降 ;近年来 ,亚洲发展中国家的私人农业科研投资迅速增长 。 展开更多
关键词 发展中国家 农业科研 投资现状 拉丁美洲 非洲 亚洲
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东亚和早期人类第一次大迁徙浪潮 被引量:14
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作者 侯亚梅 黄慰文 《人类学学报》 CSCD 北大核心 1998年第4期293-309,共17页
以欧、亚大陆一系列考古学重要地点的发现及最新研究成果,勾勒出迄今所知早期人类走出其假想发祥地非洲的时空架构,并特别讨论了早期人类起源于东亚的可能性。
关键词 早期人类 第一次大迁徙 早更新世 中更新世 亚洲
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从“非洲起源说”研究到“DNA族群地域推断”侦查应用 被引量:2
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作者 江丽 刘京 李彩霞 《法医学杂志》 CAS CSCD 2019年第5期519-524,共6页
伴随全基因组测序、生物信息等技术的发展,单核苷酸多态性(single nucleotide polymorphism,SNP)、插入/缺失(insertion/deletion,InDel)等遗传标记被发现并大量应用,从遗传学角度逐步研究获知了现代人群的起源和遗传结构。法医遗传学... 伴随全基因组测序、生物信息等技术的发展,单核苷酸多态性(single nucleotide polymorphism,SNP)、插入/缺失(insertion/deletion,InDel)等遗传标记被发现并大量应用,从遗传学角度逐步研究获知了现代人群的起源和遗传结构。法医遗传学领域族群地域来源推断研究也应运而生并快速发展,为案件侦办过程中确定侦查方向、缩小排查范围提供了线索和科学依据。本文对目前族群推断技术的研究进展、推断方法、发展趋势等情况进行综述。 展开更多
关键词 法医遗传学 多态性 单核苷酸 非洲起源 族群地域推断 东亚
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