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汉宫春·初自南郑来成都作
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作者 陆游 《党员干部之友》 2008年第7期59-59,共1页
【赏析】 宋孝宗乾道九年(1173)春天,陆游从南郑前线调回后方成都,他虽然感到失望,但收复河山的信念仍然坚定不移,并激荡着慷慨昂扬的战斗激情。本篇即表现了这种心情。
关键词 《汉宫春·初自南郑来成都作》 陆游 文学评论 文学作品
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依达拉奉治疗急性脑梗死临床疗效观察 被引量:10
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作者 吕梅 吕军 《中国现代医生》 2008年第21期154-155,共2页
目的评价依达拉奉治疗急性脑梗死的临床疗效。方法将68例急性脑梗死患者随机分为依达拉奉组和对照组,依达拉奉组在对照组常规治疗用药的基础上另外采用依达拉奉30mg加入生理盐水100mL,静脉点滴,每天两次,14d一个疗程。观察两组治疗前后... 目的评价依达拉奉治疗急性脑梗死的临床疗效。方法将68例急性脑梗死患者随机分为依达拉奉组和对照组,依达拉奉组在对照组常规治疗用药的基础上另外采用依达拉奉30mg加入生理盐水100mL,静脉点滴,每天两次,14d一个疗程。观察两组治疗前后改良爱丁堡-斯堪的那维亚量表(SSS)及日常生活能力(ADL)的变化。结果治疗7d及14d后治疗组SSS评分及ADL评分与对照组比较差异有显著性(P<0.01或P<0.05),治疗组治疗前后SSS评分及ADL评分差异有显著性(P<0.01)。治疗组不良反应轻微。结论依达拉奉治疗急性脑梗死是安全有效的。 展开更多
关键词 依达拉奉 自南基清除剂 脑梗死
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作用力和反作用力等同共用与技术规律 被引量:4
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作者 蒋富民 《科学技术与工程》 2005年第5期288-292,共5页
通过举例讨论改变传统的应用技术而建立虚拟关系的对转拖带双转子电动机呈现的变化。对转拖带双转子电动机改变了只有一个原动组件和只保留一个机构自由度的机械设计原理,将电机中能量转换过程相互对应产生的一对作用力和反作用力,共同... 通过举例讨论改变传统的应用技术而建立虚拟关系的对转拖带双转子电动机呈现的变化。对转拖带双转子电动机改变了只有一个原动组件和只保留一个机构自由度的机械设计原理,将电机中能量转换过程相互对应产生的一对作用力和反作用力,共同提供给工作系统应用,机械原理相关内容分析可知,对转拖带双转子电动机若开发推广到相适应的实际生产中应用,不仅可以减少相应工作系统的设备配置,减小设施占用空间。 展开更多
关键词 双转拖带双转子电动机 作用力和反作用力 机构自南 虚拟技术关系 能量分配
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发展大化工 实现新跨越
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作者 彭布尔 《中国氯碱》 CAS 2001年第7期3-7,共5页
自贡因盐兴市,鸿化因"鹤"得福.浓缩了40多年的盐化发展史,鸿化通过技术创新不断发展壮大,逐步巩固了在中国化工和四川工业中的重要地位.
关键词 四川自南 化学工业 自贡鸿鹤化工股份有限公司
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Analysis of Forest Landscape Pattern in Nanling National Nature Reserve,Guangdong 被引量:3
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作者 廖芳均 何嘉 《Agricultural Science & Technology》 CAS 2013年第12期1839-1841,1876,共4页
[Objective] The study was to analyze the forest landscape in Nanling Na- tional Nature Reserve to provide information for the protection of local forest ecosys- tems. [Method] With the documents of 1:10 000 topograph... [Objective] The study was to analyze the forest landscape in Nanling Na- tional Nature Reserve to provide information for the protection of local forest ecosys- tems. [Method] With the documents of 1:10 000 topographic maps, updated Forest Resource Inventory Data, based on the GIS platform and Fragstats software, the paper analyzed the patterns and heterogeneity of forest landscapes by adopting the landscape ecological theory and the method of landscape index. [Result] The forest landscape types, in terms of area occupation from large to small, are in the order of evergreen broad-leaved forest, coniferous mixed forest, evergreen and deciduous broad-leaved mixed forest, shrubs, mixed needle leaf forest, suitable land for forest deciduous broad-leaved forest and non-forest. [Conclusion] Overall, the Reserve had maintained sufficient forest landscape diversity with a low level fragmentation. The distribution of various types of forest landscape was extremely uneven, dominated by several types such as evergreen broad-leaved forest, coniferous forest, etc. 展开更多
关键词 Forest landscapes Landscape patterns NANLING Nature reserve
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制氢装置酸性水汽提塔问题及解决措施
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作者 吴建辉 王何伟 +1 位作者 安冬 李宝强 《设备管理与维修》 2018年第1期39-40,共2页
制氢装置酸性水汽提塔处理的酸性水长期不合格,对该填料塔进行拆检,从设计及安装方面,分析塔内构件存在诸如填料支承板自由截面过小、升气管底部未满焊等问题并进行相应改进。
关键词 填料塔 支承板 自南截面 升气管
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ON EVOLUTION OF MAN-LAND SYSTEM IN OASIS-Taking Minqin Basin as a Case 被引量:2
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作者 MIAOLei-lei CAIWei-bin 《Chinese Geographical Science》 SCIE CSCD 2002年第3期199-205,共7页
Human beings have had a tremendous i mpact on natural ecosystems and are n ow the principal power to change the biosphere.It is logical t hat we should pay close attention to t he interaction between human system s an... Human beings have had a tremendous i mpact on natural ecosystems and are n ow the principal power to change the biosphere.It is logical t hat we should pay close attention to t he interaction between human system s and environ-mental systems.Taking Minqin basin,Gansu Province,as a case,this paper focuses on the evolution of regional physi-cal environments and the cultural sy stems by which people maintain their relationships with those environme nts.This pa-per presents the conceptual framewo rk for the man-land system.Expectin g to accelerate the regional sustain able develop-ment,it also analyses the evolution ary mechanism of regional man-land s ystem.On the basis of reviewing and a nalyzing the evolution of man-land system in Minqin basin,the paper also brings fo rward an adjusting mode for the studi ed area,which consists of three aspects:to b uild up a concept that economic growt h must harmonize with environmental quality’s and land productivity’s improvemen t;to make a whole planning and management in the drainage area;and to push for-ward the technique of water-saving i rrigation and establish water-saving agricultural system.It’s meanin gful for resource exploitation and sustainable development of Chinese northwestern arid area,which is represented by Minqin basin,by under-standing what great changes the basin has experienced and is experiencin g at the global background,and studying its time order and territorial structure,th e system’s character and law of evolu tion,trend and the regulating ways t o improve man-land relationship. 展开更多
关键词 minqin basin man-land system man-land relationship OASIS
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Natural mortality estimation and rational exploitation of purpleback flying squid Sthenoteuthis oualaniensis in the southern South China Sea 被引量:3
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作者 王雪辉 邱永松 +1 位作者 张鹏 杜飞雁 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第4期902-911,共10页
Based on the biological data of purpleback flying squid(Sthenoteuthis oualaniensis)collected by light falling-net in the southern South China Sea(SCS) during September to October 2012 and March to April 2013,growth an... Based on the biological data of purpleback flying squid(Sthenoteuthis oualaniensis)collected by light falling-net in the southern South China Sea(SCS) during September to October 2012 and March to April 2013,growth and mortality of 'Medium' and 'Dwarf' forms of squid are derived using the Powell-Wetherall,ELEFAN methods and length-converted catch curves(FiSAT package).Given a lack of commercial exploitation,we assume total mortality to be due entirely to natural mortality.We estimate these squid have fast growth,with growth coefficients(k) ranging from 1.42 to 2.39,and high natural mortality(M),with estimates ranging from 1.61 to 2.92.To sustainably exploit these squid stocks,yield per recruitment based on growth and natural mortality was determined using the Beverton-Holt dynamic pool model.We demonstrate squid stocks could sustain high fishing mortality and low ages at first capture,with an optimal fishing mortality >3.0,with the optimal age at first capture increased to 0.4-0.6 years when fishing mortality approached optimal levels.On the basis of our analyses and estimates of stock biomass,we believe considerable potential exists to expand the squid fishery into the open SCS,relieving fishing pressure on coastal waters. 展开更多
关键词 purpleback flying squid Sthenoteuthis oualaniensis mortality dynamic pool model FISHERY South China Sea
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The Making of Water-Floating Seasonal Cuisine and Its Association to Tourism Development in An Giang Province
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作者 Le Thi 《International Relations and Diplomacy》 2018年第5期298-305,共8页
Floods have been popularly understood as the nightmares of human beings for their devastation causes. Floods in traditional Vietnamese minds are of the same type since ancient Vietnamese used a metaphor to address the... Floods have been popularly understood as the nightmares of human beings for their devastation causes. Floods in traditional Vietnamese minds are of the same type since ancient Vietnamese used a metaphor to address the floods in Red River Delta (Hanoi area) as un-auspicious marine spirit Thuy Tinh being defeated by the inland spirit Son Tinh in the legendary battle of life. Therefore, as being expressed in many cultures, floods are symbol of death and loss, and human beings have always attempted to get rich of or overcome the floods. However, the floods, under the awareness and pragmatic life of the people of An Giang Province as well as the whole Mekong River Delta (in Southern Vietnam), the floods are considered as the sign of wealth and happiness. What makes the floods to be so auspiciously acknowledged, and how do people manage to ~exploit" the floods to enrich their life? This paper is to investigate and generalize the approaches of utilizing the floods' resources to diversify their life, especially in cuisine culture. The research learns that the regularly stable floods in the Mekong River system strongly and positively affects the life of the local residents, and the community is further wise to exploit and transform the natural resources into their cultural world, mentally and materially, among which, ecotourism is a potentially prospective field 展开更多
关键词 An Giang water-floating season CUISINE transformation ECOTOURISM
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Automatic detection of oceanic mesoscale eddies in the South China Sea 被引量:1
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作者 夏琼 申辉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第5期1334-1348,共15页
This study focuses on the spatial and temporal distribution characteristics of mesoscale eddies in the South China Sea(SCS). An automatic eddy detection method,based on the geometry of velocity vectors,was adopted to ... This study focuses on the spatial and temporal distribution characteristics of mesoscale eddies in the South China Sea(SCS). An automatic eddy detection method,based on the geometry of velocity vectors,was adopted to obtain an eddy dataset from 21 years of satellite altimeter data. Analysis revealed that the number of anticyclonic eddies was nearly equal to cyclonic eddies; in the SCS,cyclonic eddies are generally stronger than anticyclonic eddies and anticyclonic eddies are larger and longer-lived than cyclonic eddies. Anticyclonic eddies tend to survive longer in the spring and summer,while cyclonic eddies have longer lifetimes in the autumn and winter. The characteristics and seasonal variations of eddies in the SCS are strongly related to variations in general ocean circulation,in the homogeneity of surface wind stress,and in the unevenness of bottom topography in the SCS. The spatial and temporal variation of mesoscale eddies in the SCS could,therefore,be an important index for understanding local hydrodynamics and regional climate change. 展开更多
关键词 South China Sea mesoscale eddies eddy detection ALTIMETER STATISTICS
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The Impact of the Cognition of Landscape Experience on Tourist Environmental Conservation Behaviors 被引量:4
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作者 ZHANG Yu-ling ZHANG Jie +4 位作者 ZHANG Hong-Lei CHENG Shao-wen GUO Yong-rui MA Jin-hai SUN Jing-rong 《Journal of Mountain Science》 SCIE CSCD 2015年第2期501-517,共17页
This article explores the relationship between the tourist's cognition of the landscape experience and the environmental conservation efforts at three distinct tourist sites in mountains of southwestern China. A t... This article explores the relationship between the tourist's cognition of the landscape experience and the environmental conservation efforts at three distinct tourist sites in mountains of southwestern China. A total of 1500 on-site questionnaire surveys were distributed and 1142 valid questionnaires were used for statistical analysis. Results from multi-group path analysis showed that both cognition of the cultural landscape experience and cognition of the natural landscape experience had positive impacts on environmental conservation behaviors and behavior intentions of tourists. Results from comparative analysis among the three tourist sites indicated that cognition of the cultural landscape experience had a stronger power to predict senior environmental conservation behaviors and behavior intentions than cognition of the natural landscape experience, whereas cognition of the natural landscape experience had more power to predict general environmental conservation behaviors and behavior intentions than cognition of the cultural landscape experience. Furthermore, our findings benefit environmental management and sustainabilityat tourist sites. 展开更多
关键词 Landscape experience Tourist behaviors Environmental conservation COGNITION EMOTION
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Detection and Quantitative Analysis of Dominant Bacteria On Aging Flue-cured Tobacco Leaves 被引量:3
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作者 Fang LIU Zhe ZHAO Mingqin ZHAO 《Agricultural Science & Technology》 CAS 2016年第11期2611-2614,共4页
[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, ... [Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, neutro-protein, polyphenol in different aging period were investigated using Henan flue-cured tobacco leaves. [Result] Results showed that the DNA copies of Bacillus megaterium increased initially but decreased subsequently with the aging time. The DNA copies of Bacillus per gram of tobacco leaf surface reached the maximum number at 6 months aging. The activities of four enzymes showed the same variation trend as in DNA copies, and also reached the highest level at 6 months aging. Chemical ingredients, however, displayed a downward trend. The variation of enzyme activity and content of chemical composition were reflected in the changes of DNA copies in Bacillus megaterium. [Conclusion] The result indicate that Bacillus megaterium was the internal motivation of flue-cured tobacco natural aging. 展开更多
关键词 Flue-cured tobacco AGING Real-time PCR SYBR Green DNA copies
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The Arabidopsis Spontaneous Cell Death1 gene, encoding a ζ-carotene desaturase essential for carotenoid biosynthesis, is involved in chloroplast development, photoprotection and retrograde signalling 被引量:8
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作者 Haili Dong Yan Deng +7 位作者 Jinye Mu Qingtao Lu Yiqin Wang Yunyuan Xu Chengcai Chu Kang Chong Congming Lu Jianru Zuo 《Cell Research》 SCIE CAS CSCD 2007年第5期458-470,共13页
Carotenoids, a class of natural pigments found in all photosynthetic organisms, are involved in a variety of physiological processes, including coloration, photoprotection, biosynthesis of abscisic acid (ABA) and ch... Carotenoids, a class of natural pigments found in all photosynthetic organisms, are involved in a variety of physiological processes, including coloration, photoprotection, biosynthesis of abscisic acid (ABA) and chloroplast biogenesis. Although carotenoid biosynthesis has been well studied biochemically, the genetic basis of the pathway is not well understood. Here, we report the characterization of two allelic Arabidopsis mutants, spontaneous cell death1-1 (spcl-1) and spc1-2. The weak allele spc1-1 mutant showed characteristics of bleached leaves, accumulation of superoxide and mosaic cell death. The strong mutant allele spc1-2 caused a complete arrest of plant growth and development shortly after germination, leading to a seedling-lethal phenotype. Genetic and molecular analyses indicated that SPC1 encodes a putative ζ-carotene desaturase (ZDS) in the carotenoid biosynthesis pathway. Analysis of carotenoids revealed that several major carotenoid compounds downstream of SPC 1/ZDS were substantially reduced in spc1-1, suggesting that SPC 1 is a functional ZDS. Consistent with the downregulated expression of CAO and PORB, the chlorophyll content was decreased in spc1-1 plants. In addition, expression of Lhcb1. 1, Lhcbl. 4 and RbcS was absent in spc1-2, suggesting the possible involvement of carotenoids in the plastid-to-nucleus retrograde signaling. The spc1-1 mutant also displays an ABA-deficient phenotype that can be partially rescued by the externally supplied phytohormone. These results suggest that SPC1/ZDS is essential for biosynthesis of carotenoids and plays a crucial role in plant growth and development. 展开更多
关键词 carotenoid biosynthesis cell death chloroplast development PHOTOPROTECTION Arabidopsis SPC1/ZDS
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Pursuing a World of Ecological Harmony An Ecofeminist Study of Willa Cather's Pioneer Works
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作者 GAO Li-li WANG Ying 《Sino-US English Teaching》 2014年第7期542-546,共5页
Willa Cather (1873-1947) is one of the greatest women writers in the history of American literature, whose reputation centers on her novels about celebrating pioneer immigrants on Nebraska prairie and the American s... Willa Cather (1873-1947) is one of the greatest women writers in the history of American literature, whose reputation centers on her novels about celebrating pioneer immigrants on Nebraska prairie and the American southwest. For long Willa Cather's pioneer works have gained great critical acclaim and have been interpreted from different perspectives such as mythicism, romanticism, and feminism. This paper, interpreting Willa C ather' s classical pioneer works of the three periods from the 1920s to the 1930s-My A ntonia ( 1918), A Lost Lady (1923), and "Neighbor Rosicky" (1930), is devoted to making a full exploration into the evolution of her ecological thoughts from an ecofeminist perspective. In Willa Cather's three pioneer works of different creative stages, she deliberately constructs three eco-worlds as a standard of ecological harmony. In her three eco-worlds, Willa Cather not only investigates the relationship between man and nature, but also involves androcentrism, patriarchy, and other ecofeminist topics. Willa Cather's ecological views have undergone changes in her representation of three successive phrases. To interpret Willa Cather's pioneer works from the perspective of ecofeminism can provide a deeper comprehension about her works and her ecological thoughts for the world. 展开更多
关键词 Willa Cather pioneer works ECOFEMINISM ecological harmony
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Climate Change Adaptation for People and Nature:A Case Study from the U.S.Southwest
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作者 Patrick D.MCCARTHY 《Advances in Climate Change Research》 SCIE 2012年第1期22-37,共16页
In the U.S.Southwest,global climate change,acting in concert with extant stressors such as urbanization and over-allocation of water resources,is changing ecosystems in measureable and sometimes dramatic ways.Twenty-f... In the U.S.Southwest,global climate change,acting in concert with extant stressors such as urbanization and over-allocation of water resources,is changing ecosystems in measureable and sometimes dramatic ways.Twenty-first century projections indicate accelerating climate change and cascading ecological consequences.Effects observed to date include large-scale forest dieback,large and severe wildfires,and changes in the flow regimes of rivers and streams with attendant changes to riparian and aquatic ecosystems.Rising temperatures and changing precipitation patterns are pushing ecosystems across physiological and ecological thresholds,causing widespread mortality and,in some cases,major changes in composition,structure and function.These changes have prompted action by the conservation community to reduce the adverse effects of climate change.The Southwest Climate Change Initiative(SWCCI),a project led by The Nature Conservancy,works with local stakeholders in affected landscapes,reduces adverse impacts on ecological and social systems using scientific knowledge and practical tools.The Initiative has learned through practical experience that: 1) managers must embrace change and manage for resilience rather than resistance;2) strong local science-management partnerships are critical to effective adaptation planning and implementation;3) planners and managers must broaden the scope and accelerate the pace of conservation activities if ecosystem services are to be sustained;4) adaptation often does not require radically new or different management practices,rather,conservationists already have many of the tools they need;and 5) rapid documentation and widespread communication of methods and findings can build rapidly regional capacity for climate change adaptation.Our experience suggests that adaptation efforts can be effective if they are focused at the local scale;employ learning networks;and engage in ecosystem-based adaptation:the sustainable management,conservation and restoration of ecosystems so that they continue to provide the services that allow people to thrive in changing environments. 展开更多
关键词 climate change adaptation ecosystem-based adaptation ecological thresholds learning networks
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Economic impacts of the Natural Forest Protection Program in Yunnan Province, China:an input-output analysis 被引量:1
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作者 Wang Zanxin Margaret M. Calderon 《Ecological Economy》 2008年第1期66-73,共8页
The paper assesses the economic impacts of the natural forest protection program (NFPP) on the economy of Yunnan Province, China.in terms of gross output, value added,employment, and household income. An inputoutput... The paper assesses the economic impacts of the natural forest protection program (NFPP) on the economy of Yunnan Province, China.in terms of gross output, value added,employment, and household income. An inputoutput model is developed to estimate NFPP's economic impacts by means of backward linkages in the forestry sector and logging and haudage sector. It is found than the NFPP has positive impacts on gross output, value added and houschold income in the initial year, but has significantly negative impacts on the regional economy in the following years as the investment decreases. 展开更多
关键词 NFPP Input-output analysis Economic inpacts
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Effectiveness of Nature Reserves for Natural Forests Protection in Tropical Hainan: a 20 Year Analysis 被引量:4
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作者 YU Bowei CHAO Xuelin +2 位作者 ZHANG Jindong XU Weihua OUYANG Zhiyun 《Chinese Geographical Science》 SCIE CSCD 2016年第2期208-215,共8页
The establishment of nature reserves is a key approach for biodiversity conservation worldwide. However, there is a lack of unified methodology to evaluate the effectiveness of nature reserves, particularly in China, ... The establishment of nature reserves is a key approach for biodiversity conservation worldwide. However, there is a lack of unified methodology to evaluate the effectiveness of nature reserves, particularly in China, the world′s most populous nation supporting some of the most valuable biodiversity hotspots in the world. In this study, we conducted a long-term and large-scale analysis of the effectiveness of 20 of the earliest nature reserves established in Hainan Province, an island home to among the highest concentration of plants and animals in China. Remote sensing imagery from 1988, 1998, and 2008 were analyzed to investigate the temporal and spatial changes of natural forests in these nature reserves and surrounding areas. We also conducted transition matrix analysis and principle component analysis to identify the driving factors that affect the protection effectiveness of nature reserves. The results were as follows: 1) During the 20-year period from 1988 to 2008, natural forests coverage of the 20 studied nature reserves dropped 2.34 percentage points, whereas the natural forests coverage dropped 11.31 percentage points in a 0–5 km outside reserve buffer and 9.36 percentage points in a 5–10 km outside reserve buffer, indicating a significant inhibitory effect of the nature reserves on the loss of natural forests. 2) Natural forests coverage dropped in 60% of the studied nature reserves during the 20-year period, suggesting a poor protection effectiveness of these reserves, while the coverage proportion showed some increase(0%/yr–5%/yr) in other reserves. 3) Expansion of rubber and pulp forests as part of a booming economy were the main factors affecting the effectiveness of the nature reserves for conserving natural forests in Hainan Province. The results of this study provide an important empirical basis for the protection of natural forests in Hainan Province, which can be used as a blueprint for nature reserve evaluation in other places in China. 展开更多
关键词 nature reserve natural forests reserve effectiveness Hainan Province China
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South Africa's Media Freedom Landscape and the Closures in Democracy
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作者 Glenda Daniels 《Journalism and Mass Communication》 2015年第1期9-19,共11页
This research uses a theoretical conceptual method based on Chantal Mouffe's Radical Democracy which blended with Derrida's deconstruction thesis about "democracy to come" to reach findings on the state of South A... This research uses a theoretical conceptual method based on Chantal Mouffe's Radical Democracy which blended with Derrida's deconstruction thesis about "democracy to come" to reach findings on the state of South Africa's media freedom landscape. The method is contained in the conceptual framework. The article provides the constitutional legal landscape--or the overarching laws of the land--and the co-regulatory framework within which journalists work. There are four research explications: the Protection of State Information Bill (dubbed the Secrecy Bill), a painting of the president and Freedom of Expression, an arson attack on a community radio station and finally, the death of a photojournalist at the hands of police. The argument here is that the death, the arson attack, the Secrecy Bill, and the shut-down of dissent during the exhibition of the painting of the president all undermine democracy and signify significant closures for the media in the now 20-year-old post-apartheid South Africa. The analysis and reflections will be framed within theories of radical democracy, which argue for more fights and contestations and more voices from the margins in order to deepen democracy, rather than rational consensus which closes the spaces for greater plurality. 展开更多
关键词 radical democracy MEDIA freedom of expression SECRECY CLOSURES aporias
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Manganese potential mapping in western Guangxi-southeastern Yunnan(China) via spatial analysis and modal-adaptive prospectivity modeling 被引量:8
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作者 Fan-yun WANG Xian-cheng MAO +1 位作者 Hao DENG Bao-yi ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第4期1058-1070,共13页
While the region of western Guangxi-southeastern Yunan, China, is known and considered prospective for manganese deposits, carrying out prospectivity mapping in this region is challenging due to the diversity of geolo... While the region of western Guangxi-southeastern Yunan, China, is known and considered prospective for manganese deposits, carrying out prospectivity mapping in this region is challenging due to the diversity of geological factors, the complexity of geological process and the asymmetry of geo-information. In this work, the manganese potential mapping for further exploration targeting is implemented via spatial analysis and modal-adaptive prospectivity modeling. On the basis of targeting criteria developed by the mineral system approach, the spatial analysis is leveraged to extract the predictor variables to identify features of the geological process. Specifically, a metallogenic field analysis approach is proposed to extract metallogenic information that quantifies the regional impacts of the synsedimentary faults and sedimentary basins. In the integration of the extracted predictor variables, a modal-adaptive prospectivity model is built, which allows to adapt different data availability and geological process. The resulting prospective areas of high potential not only correspond to the areas of known manganese deposits but also provide a number of favorable targets in the region for future mineral exploration. 展开更多
关键词 prospectivity mapping manganese deposit western Guangxi-southeastern Yunnan field analysis approach modal-adaptive prospectivity modeling
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Hydrochemistry of the Natural Low p H Groundwater in the Coastal Aquifers near Beihai, China
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作者 ZHOU Xun SHEN Ye +3 位作者 ZHANG Hua SONG Chao LI Jingwei LIU Yan 《Journal of Ocean University of China》 SCIE CAS 2015年第3期475-483,共9页
Natural weak acidic groundwater occurs in the unconfined and confined aquifers consisting of Quaternary and Neogene unconsolidated sediments near Beihai in southern Guangxi, China. Under natural conditions the groundw... Natural weak acidic groundwater occurs in the unconfined and confined aquifers consisting of Quaternary and Neogene unconsolidated sediments near Beihai in southern Guangxi, China. Under natural conditions the groundwater has low TDS(less than 200 mg L-1) and low concentrations of trace elements(less than 100 μg L-1) with a deceasing tend in contents of the Lanthanides(rare earth elements, less than 1 μg L-1) towards higher atomic number. The groundwater ranges in p H from 3.33 to 7.0 with an average value of 5.12(even lower than that of local rainwater, 5.88). p H values in the groundwater are a bit higher in rainy seasons than those in dry seasons and do not show significant increasing or decreasing trend with time. The average p H value in groundwater in the confined aquifers is even a bit lower than that in the unconfined aquifer. Comprehensive analyses of the groundwater environment suggest that H+ in the groundwater may be derived from dissociation of H2CO3, release of the absorbed H3O+ in clay layers and the acidity of rainwater. The H2CO3 in the groundwater may be formed by dissolution of CO2(g). Minerals in the unconsolidated sediment are predominated by quartz with small amount of clay minerals. The sediments undergoing a long-term weathering contain low levels of soluble constitutes. Lack of alkaline substances in the groundwater system is also helpful in the accumulation of acidity of the groundwater. 展开更多
关键词 acidic groundwater carbonic equilibrium coastal aquifer unconsolidated sediments trace elements
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