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A comparative study on transradial vs transfemoral artery access for primary percutaneous coronary intervention in patients with acute myocardial infarction
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作者 傅向华 《介入放射学杂志》 CSCD 2003年第S1期152-,共1页
Objective Comparative study on the feasibility,safety and outcome of transradial artery and transfemoral artery access for primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction(... Objective Comparative study on the feasibility,safety and outcome of transradial artery and transfemoral artery access for primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction(AMI).Methods Two hundred and eight patients with AMI episoded within 12 hours, male 159, female 49, age 58.9 ±11.9 (34~88)years, were randomly divided into transradial artery access for primary PCI (TRA pPCI) group of 106 cases and transfemoral artery access for PCI (TFA pPCI) group of 102 cases during Sept, 2000 to Aug, 2002. The protocols of the manipulation duration and the effect for TRA pPCI and TFA pPCI procedures were respectively compared, including the time of transradial artery puncture and the rate of puncture success at first time ; the time of guiding catheter engaging into target coronary ostium; the rate of patence in infarct related artery (IRA); total duration of manipulation and the successful rate.The incidence of complications such as bleeding, vessel injury,thrombi and embolism as well as the average stay of hospitalization between two groups was compared. The status and the incidance of vessel spasm were observed and the effect of medicine administration to prevent from and relieve the vascular spasm was evaluated. The time of Allen’s test before and after TRA pPCI , the inner diameter and the peak of blood velocity of the right and left radial artery were investigated with color Doppler vessel echography as well as the complications of radial artery were followed up 1 month after TRA pPCI procedure. Results Two cases in every TRA pPCI and TFA pPCI groups were crossed over each other because procedure of the transradial or transfemoral access was failure. One handred and six vessels (48 vessels in LAD,22 vessels in LCX and 36 vessels in RCA) associated with 28 vessels of total occlusion in TRA pPCI group and 102 vessels (51 vessels in LAD,18 veesles in LCX and 33 vessels in RCA) with 24 vessels in total occlusion in TFA pPCI group were angioplasticized . The successful rates of the first time puncture in access artery, the re patence IRA and pPCI were similar in TRA pPCI and TFA pPCI groups ( 93.4% vs 96.1% ;100% vs 100%; 96.2% vs 97.1% , P >0.05 ). There were no significant diffierence in the average time of puncture time of access artery ,engaging in target vessels of guiding catheters and the total procedure of PCI between the two groups ( 1.3 ±0.3s vs 1.2 ±0.3s ; 6.0 ±1.6min vs 5.8 ±0.9min ; 49.2 ±24.1min vs 46.5 ± 26.4min , P >0.05 ). The access artery complications such as bleeding ,hematoma and embolism as well the veneous thrombosis in TFA pPCI group were much more than those in TRA pPCI group(p< 0.01 ). Although slight artery spasm of 4.7% cases in TRA pPCI group was happened during the procedure of PCI , the procedure had being continued after administration of medicine to release the spasm. The time of Allen’s test ,diameter and the systolic velocity of blood in daul radial arteries were no significant change before and after pPCI.Conclusions The duration and effect by TRA pPCI for AMI with stable hemodynamics was similar to TFA pPCI. The complications such as of bleeding,vessel injury, thrombi and embolism by TRA pPCI were few, and it was unnecessary to discontinue the anticoagulation medicine. TRA pPCI might be selected as a access vessel for pPCI in AMI patients with stable hemodynamics. 展开更多
关键词 for in on A comparative study on transradial vs transfemoral artery access for primary percutaneous coronary intervention in patients with acute myocardial infarction with
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Comparative study of different theories on active earth pressure 被引量:1
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作者 S.P.Yap F.A.Salman S.M.Shirazi 《Journal of Central South University》 SCIE EI CAS 2012年第10期2933-2939,共7页
Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on com... Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on comparison between the theories. In this work, comparison between the theories with finite element analysis is done using the PLAXIS software. The comparative results show that in terms of distribution and magnitude of active earth pressure, RANKINE's theory possesses the highest match to the PLAXIS analysis. Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters Increasing soil friction angle and wall friction causes decrease in active earth pressure. In contrast, active earth pressure increases with increasing soil unit weight and height of wall. RANK/NE's theory has the highest compatibility to finite element analysis among all theories, and utilization of this theory leads to proficient retaining wall design. 展开更多
关键词 active earth pressure retaining wall PLAXIS comparative study RANKINE's theory COULOMB's theory
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A comparative study on the performances of synthetic diamond made by belt press & cubic press 被引量:1
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作者 Jia Pan~1,Lu Canhua~1,Ye Hongyu~2,Li Zhihong~3 (1.Nanyang Zhongnan Diamond Co.,Ltd.Nanyang,China) (2.Wuhan Wanbang Laser Diamond Tools Co.,Wuhan,China) (3.Industrial Diamond Association of China,Zhengzhou 450013,China ) 《金刚石与磨料磨具工程》 CAS 北大核心 2008年第S1期50-55,共6页
There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic press.It has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that ma... There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic press.It has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that made by belt press.With the on-going improvement in technology,know-how & accumulated experiences, perhaps it’ s time for us to review the qualities & performances of synthetic diamond made by the cubic press more objectively.Studies were carried out on the performances of the two kinds of diamond by choosing from top brands & top qualities,with coarser mesh sizes 20/30 & 30/40.Comparisons were made on parameters, such as TI,TTI,PPC,bulk density,compact,roughness and arealight.And the diamonds chosen were used to produce the relevant diamond core drill bits and saw blades,their respective cutting performances such as cutting efficiency,segments consumption were measured and reported in this paper.The report demonstrates that producing the high quality diamond does not depend on the type of presses(Belt or Cubic) but rather on the know-how,technology and what it is made. 展开更多
关键词 comparative study performance synthetic DIAMOND BELT press cubic PRESS
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A comparative study on three EOF analysis techniques using decades of Arctic sea-ice concentration data
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作者 陈新保 刘信陶 +1 位作者 李松年 Chow Annie 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2681-2690,共10页
Change in Arctic sea ice extent is one of the indicators of global climate changes. Spatio-temporal change and change patterns can be identified using various methods to facilitate human understanding global climate c... Change in Arctic sea ice extent is one of the indicators of global climate changes. Spatio-temporal change and change patterns can be identified using various methods to facilitate human understanding global climate changes. Three empirical orthogonal function(EOF) techniques are discussed and applied to decades of sea-ice concentration(SIC) dataset in Arctic area for identifying independent patterns. It was found that: 1) discrepancies exist in magnitude and scope for each EOF pattern, however, the first two leading EOFs of variability possess high similarities in structure and shape; 2) Even though there are somewhat differences in amplitude of each PC mode, the first two leading PC modes maintain consistent in overall trend and periodicity; 3) There are significant discrepancies and inconsistencies in the third and fourth leading EOF and PC modes. The accuracies of three techniques are further validated in representing the physical phenomena of SIC anomaly patterns. 展开更多
关键词 empirical orthogonal functions sea-ice concentration comparative study patterns arctic
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A Comparative Study of State and Guojia from A Cross - disciplinary Perspective
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作者 Li Gengyan 《学术界》 CSSCI 北大核心 2015年第12期305-309,共5页
Language is a carrier of culture and a comparative study of the source language and the target language in translation will reflect the differences and similarities of two cultures.Due to different socio-cultural back... Language is a carrier of culture and a comparative study of the source language and the target language in translation will reflect the differences and similarities of two cultures.Due to different socio-cultural backgrounds and distinctive characteristics of Chinese and English,some concepts about culture are accordingly expressed and translated differently,and it is worthwhile to reflect on these concepts from a cross-disciplinary perspective,such as State and Guojia.The paper tries to explore the connotations of Guo,Jia,Guojia and State,and illustrates how different culture origins results in incomplete equivalence in translation,which can be regarded as a blessing in the times of culture diversity. 展开更多
关键词 跨学科 语言翻译 文化背景 文化多样性 文化起源 源语言 不完全 汉语
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Solid-state Effects on Luminescence Properties of TADF Emitters Based on Pyrido[2,3-b]pyrazine-Dihydrophenazasilines Donor-acceptor Structures:Theoretical Study
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作者 LI Yuheng LIU Meiqi +2 位作者 HOU Baoming PAN Yuyu YANG Bing 《发光学报》 北大核心 2025年第2期354-365,共12页
Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular st... Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular structure and luminescence properties,TADF molecules are far from meeting the needs of practical applications in terms of variety and number.In this paper,three twisted TADF molecules are studied and their photophysical properties are theoretically predicted based on the thermal vibrational correlation function method combined with multiscale calculations.The results show that all the molecules exhibit fast reverse intersystem crossing(RISC)rates(kRISC),predicting their TADF luminescence properties.In addition,the binding of DHPAzSi as the donor unit with different acceptors can change the dihedral angle between the ground and excited states,and the planarity of the acceptors is positively correlated with the reorganization energy,a property that has a strong influence on the non-radiative process.Furthermore,a decrease in the energy of the molecular charge transfer state and an increase in the kRISC were observed in the films.This study not only provides a reliable explanation for the observed experimental results,but also offers valuable insights that can guide the design of future TADF molecules. 展开更多
关键词 solid-state effects thermally activated delayed fluorescence(TADF) theoretical study multi-scale simulation
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Corrigendum to“Mechanistic Insights into Water-Mediated CO_(2)Electrochemical Reduction Reactions on Cu@C_(2)N Catalysts:A Theoretical Study”[Acta Physico-Chimica Sinica(2024)40,2303040]
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《物理化学学报》 北大核心 2025年第5期144-144,共1页
Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian Univers... Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,Liaoning Province,China. 展开更多
关键词 chemical engineeringdalian theoretical study water mediated Cu C N catalysts fine chemicalsschool CO electrochemical reduction chemical engineeringstate
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A Comparative Study of Traditional Chinese and Western Cultural Connotations
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作者 Zhang Mo Zhu Dequan 《学术界》 CSSCI 北大核心 2016年第3期257-263,共7页
By conducting specific comparison on traditional Chinese and western cultural connotations,it can be summarized that the specific differences existing in the elements of traditional cultural connotations as well as th... By conducting specific comparison on traditional Chinese and western cultural connotations,it can be summarized that the specific differences existing in the elements of traditional cultural connotations as well as their impacts on the overall development of social cultures. Effective research and exploration processes could be further formed to propel the overall development of social cultures,so that the roles of traditional Chinese and western cultural connotations in inheriting and developing traditional cultures can be fully revealed. 展开更多
关键词 文化内涵 传统文化 社会文化
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A Comparative Study on Two Techniques of Reducing the Dimension of Text Feature Space
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作者 Yin Zhonghang, Wang Yongcheng, Cai Wei & Diao Qian School of Electronic & Information Technology, Shanghai Jiaotong University, Shanghai 200030, P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第1期87-92,共6页
With the development of large scale text processing, the dimension of text feature space has become larger and larger, which has added a lot of difficulties to natural language processing. How to reduce the dimension... With the development of large scale text processing, the dimension of text feature space has become larger and larger, which has added a lot of difficulties to natural language processing. How to reduce the dimension has become a practical problem in the field. Here we present two clustering methods, i.e. concept association and concept abstract, to achieve the goal. The first refers to the keyword clustering based on the co occurrence of 展开更多
关键词 in the same text and the second refers to that in the same category. Then we compare the difference between them. Our experiment results show that they are efficient to reduce the dimension of text feature space. Keywords: Text data mining
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Comparative Proteomics Study on Human High-metastatic Large Cell Lung Cancer Cell Lines Before and After Transfecting with Nm23-H1 Gene
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作者 Liwei GAO Yu FAN Li MA Jun CHEN Seng WEI Zhigang LI Hon-gyu LIU Haisu WAN Zhihao WU QInghua ZHOU 《中国肺癌杂志》 CAS 2009年第6期497-498,共2页
Background and Objective Lung cancer is not only the most dangerous threating tumor to human’s health and life, but also a malignant tumor with poor prognosis. In the past 10 years,
关键词 肺癌 癌细胞 扩散 治疗
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Comparative Proteomics Study on Human High-metastatic Large Cell Lung Cancer Cell Lines with Differential Metastatic Potential
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作者 Xingyang XUE Yu FAN Li MA Jun CHEN Sen WEI Zhigang LI Hongyu LIU Haisu WAN Zhihao WU Qinghua ZHOU 《中国肺癌杂志》 CAS 2009年第6期521-522,共2页
Background and Objective Lung cancer is not only the most dangerous threating tumor to humans health and life, but also a malignant tumor with poor prognosis. It has been
关键词 肺癌 癌细胞 治疗 疗效
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A Comparison study of First and Second Language Acquisition 被引量:2
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作者 赵健 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S1期339-341,共3页
More focuses of foreign language teaching theory and practice are on the study of first language and second language acquisition. The article deals with the concept of first and second language acquisition, the relati... More focuses of foreign language teaching theory and practice are on the study of first language and second language acquisition. The article deals with the concept of first and second language acquisition, the relationship between them and the factors influencing on them. The characteristics of the children acquisition and adult acquisition are also studied. 展开更多
关键词 first language acquisition second language acquisition comparison study
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Comparative analysis of chemical components between barks and leaves of Eucommia ulmoides Oliver 被引量:10
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作者 周菊峰 张泰铭 +1 位作者 陈望爱 梁逸曾 《Journal of Central South University》 SCIE EI CAS 2009年第3期371-379,共9页
The chemical components of the essential oils in the barks and leaves of Eucommia ulmoides Oliver were analyzed and compared by chromatograms and mass spectra technique, heuristic evolving latent projections (HELP), a... The chemical components of the essential oils in the barks and leaves of Eucommia ulmoides Oliver were analyzed and compared by chromatograms and mass spectra technique, heuristic evolving latent projections (HELP), alternative moving window factor analysis (AMWFA) algorithms and normalization method based on the peak areas; the flavones in the barks and leaves of Eucommia ulmoides Oliver were separated on an ODS column by gradient elution carried out with the flow phase consisting of water, methanol and phosphoric acid (0.1%), and their contents were quantitatively determined by standard curve method and diode array detection (DAD) at 362 nm. The results show that 68 and 73 compounds respectively from essential oils of the barks and leaves of Eucommia ulmoides Oliver are identified, and there are 33 mutual compounds among 108 compounds determined. The total contents of these volatile components of the two samples possess 92.9% and 97.75% of the gross of the relevant essential oils, respectively; the contents of the rutin, quercetin and kaempferol in the barks and leaves of Eucommia ulmoides Oliver are 0.016 9, 0.003 6, 0.002 1 and 0.064 4, 0.030 2, 0.010 0 mg/g, respectively, and the determination recoveries are 95.2%-106.2%. The comparative analysis shows that for the barks and leaves of Eucommia ulmoides Oliver, there are significant differences in their components of the relevant essential oils and flavones. 展开更多
关键词 couple chromatography chemometric algorithm comparative analysis essential oil FLAVONE Eucommia ulmoides Oliver
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Comparison of thermal and mechanical properties of γ'-Pt_(3)Al and γ'-Ni_(3)Al phases:A first principles study 被引量:1
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作者 ZHANG Xiao ZHOU Xiao-long +2 位作者 YAO Bi-xia YU Jie WANG Li-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期32-42,共11页
High-temperature Ni-based alloys are widely used in the aerospace field due to their excellent properties,but the shortcomings of brittle fracture at the grain boundaries and poor plasticity at room temperature also l... High-temperature Ni-based alloys are widely used in the aerospace field due to their excellent properties,but the shortcomings of brittle fracture at the grain boundaries and poor plasticity at room temperature also limit their development to a certain extent.Researchers found that there areγ′precipitation phases similar to Ni_(3)Al in Pt-Al based alloys.In this paper,the CASTEP code of Materials Studio software package is used to simulate the thermal and mechanical properties ofγ′-Pt_(3)Al phase andγ′-Ni_(3)Al phase.By comparing the performance characteristics of the electronic structure,mechanical properties and point defect structure of the two,it is found that the stability,elastic deformation resistance and high temperature creep resistance of theγ′-Pt_(3)Al phase are better than those of theγ′-Ni_(3)Al phase.This will provide theoretical guidance for promoting the development of Pt-Al-based high-temperature materials. 展开更多
关键词 first-principles study SUPERALLOY γ'-Pt 3 Al electronic properties mechanical-properties
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The Role of Comparative Literature for Building a Community of Shared Future for Mankind
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作者 Li Yongmei 《学术界》 CSSCI 北大核心 2019年第10期195-206,共12页
The human society is an interdependent community of shared future.Rooted in the foundation of “Great Harmony” ideology in Chinese traditional culture,the idea of “a community of shared future for mankind” is an im... The human society is an interdependent community of shared future.Rooted in the foundation of “Great Harmony” ideology in Chinese traditional culture,the idea of “a community of shared future for mankind” is an important part of the socialism thoughts with Chinese characteristics in new era.The similarities and differences of cultures are the base of complementation and premise of innovative development rather than the source of conflicts.The core value of community of shared future is harmony,which with the goal of win-win can be achieved only by actively advocating cultural diversity,strengthening the effective and equal dialogue and understanding and complementing between different cultures or civilizations,and creating an inclusive,tolerant and reasonable peaceful environment.In this respect,the comparative literature research should inevitably play its irreplaceable role as a bridge to enable the communication,dialogue and understanding between eastern and western literature and cultures.The communication between cultures is homogeneous but the interaction between cultural soils as well as national cultures is heterogeneous.During the communication process of literature works,it’s necessary to further study the literature content under cultural differences.The community of shared future for mankind is not only a new idea for global governance but also a new kind of expression of the habitat guarding and building awareness;it is the real and physically objective existence and also the imaginary and emotional spirit pursuit.In the context that the comparative literature is trying to develop into the world literature,it’s the mission for mankind to make it possible the wide transmission,reading and studying of the diversified and unique literature works of different countries,which can manifest the common value connotation of human beings,and to spare no effort to remove obstacles from the path to the destination of a community of shared future for mankind. 展开更多
关键词 comparative LITERATURE a COMMUNITY of SHARED FUTURE for mankind VALUES
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Comparative Analysis on Public and Private Partnership Legislation
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作者 Fu Jingjing Li Shuang 《学术界》 CSSCI 北大核心 2019年第6期204-213,共10页
Public-Private Partnerships (PPPs) mode is a new governance mode which combines the advantages of government,private investor and the financial institution together.However,there is no sound legal system for PPPs in C... Public-Private Partnerships (PPPs) mode is a new governance mode which combines the advantages of government,private investor and the financial institution together.However,there is no sound legal system for PPPs in China at present.Therefore,it is critical to build a PPP legal legislation in order to facilitate investments in complex and long-term PPP arrangements,reduce transaction costs,ensure appropriate regulatory controls,and provide legal and economic mechanisms to enable the resolution of contract disputes.This article provides an international perspective on PPP legal framework by drawing upon the existing of PPP laws from several countries. 展开更多
关键词 PPPs LEGISLATION comparative ANALYSIS
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Comparative Proteomic Analysis of the Fiber Elongating Process in Cotton 被引量:1
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作者 LIU Jin-yuan,YANG Yi-wei,BIAN Shao-min(Laboratory of Molecular Biology,Department of Biological Sciences and Biotechnology,Tsinghua University,Beijing 100084,China) 《棉花学报》 CSCD 北大核心 2008年第S1期58-,共1页
A comparative proteomic analysis was performed to explore the mechanism of cell elongation in developing cotton fibers.The temporal changes of global proteomes at five representative
关键词 comparative Proteomic Analysis of the Fiber Elongating Process in Cotton
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Comparison of the Results in CO_2 Sequestration Field Experience and Laboratory Studies
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作者 Lijiang Duan,Shuheng Tang School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期153-153,共1页
Sequestration of carbon dioxide(CO<sub>2</sub>) in deep, unminable coalseam is an innovative technology, because it can not only reduce greenhouse gas in the atmosphere,but also enhance coalbed methane r... Sequestration of carbon dioxide(CO<sub>2</sub>) in deep, unminable coalseam is an innovative technology, because it can not only reduce greenhouse gas in the atmosphere,but also enhance coalbed methane recovery(CO<sub>2</sub>-ECBM).Lots of research have been carried out on this topic in recent years.However,few of them were focused on the comparison of the 展开更多
关键词 CO2 SEQUESTRATION ECBM field EXPERIENCE LABORATORY study
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Revealed Comparative Advantage and Competitiveness in Chinese Agricultural Sectors
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作者 ZHAN Jing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2005年第2期163-168,共6页
This paper examined the competitiveness of Chinese agricultural products, in relation to the rest of the world, based on the index of revealed comparative advantage, using lots of data during period of 1980 to 2000. T... This paper examined the competitiveness of Chinese agricultural products, in relation to the rest of the world, based on the index of revealed comparative advantage, using lots of data during period of 1980 to 2000. The index is useful in identifying the demarcation between comparative advantage and comparative disadvantage, though a problem exits when using it. China is shown to have a comparative advantage in a range of agricultural products, including edible vegetables and tea. This complements the findings of those studies that have used price and cost based on approaches in identifying competitiveness in agricultural products. Results indicated that the RCA values had been weakening over the 21-year period. These have vastly different implication for the future reform in China's agriculture, 展开更多
关键词 comparative advantage RCA values: competitiveness
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Comparative Genetics of Floral Morphology in Diploid and Allotetraploid Gossypium
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作者 CHEE Peng W 《棉花学报》 CSCD 北大核心 2008年第S1期115-,共1页
The cultivated Gossypium A genome diploid species G.arboreum and G.herbaceum and the allotetraploid species G.hirsutum and G.barbadense share common morphology for various floral traits,
关键词 QTLS comparative Genetics of Floral Morphology in Diploid and Allotetraploid Gossypium
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