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Classification and Source Materials of Continental Crust Transformation Series Granitoids in South China 被引量:4
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作者 Liu Changshi Zhu Jinchu +1 位作者 Shen Weizhou Xu Shijin Department of Earth Sciences, Nanjing University, Nanjing, Jiangsu Jiang Minxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1990年第3期287-298,共12页
The granitoids of the continental crust transformation series in South China may be divided into threetypes: (1) synorogenic migmatic and magmatic type. (2) anorogenic continental crust anatexis type, and (3)syncollis... The granitoids of the continental crust transformation series in South China may be divided into threetypes: (1) synorogenic migmatic and magmatic type. (2) anorogenic continental crust anatexis type, and (3)syncollision type. Based on the results of Sr and Nd isotopic determinations, the source material compositionof the three types of granitoids is calculated with crust-mantle binary mixing simulation. The calculations indi-cate that the granitoids of the first type consist of 78.6-89.7% upper crust endmember materials and15.0-10.3% depleted mantle endmember materials, the granitoids of the second type are composed of 63.7%upper crust endmember materials and 36.3% depleted mantle endmember materials, and those of the third type100% upper crust endmember materials. Hence. the source material composition of the granitoids of all thethree types is dominated by upper crust endmembers. 展开更多
关键词 classification and source Materials of Continental Crust Transformation Series Granitoids in South China source
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Source Rock Classification and the Basic Structure of Coal and Kerogen
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作者 金奎励 杨陆武 《Journal of China University of Mining and Technology》 2002年第1期1-5,共5页
In accordance with the confusion on classification of source rocks, the authors raised a source rock classification for its enriched and dispersed organic matter types based on both Alpern’s idea and maceral genesis/... In accordance with the confusion on classification of source rocks, the authors raised a source rock classification for its enriched and dispersed organic matter types based on both Alpern’s idea and maceral genesis/composition. The determined rock type is roughly similar to palynofacies of Combaz , whereas it is "rock maceral facies (for coal viz. coal facies)" in strictly speaking. Therefore, it is necessary to use the organic ingredients classification proposed by the authors so that it can be used for both maceral analysis and environment research . This source rock classification not only shows sedimentology and diagenetic changes but also acquires organic matter type even if hydrocarbon potential derived from maceral’s geochemical parameters. So, it is considered as genetic classification. The "rock maceral facies" may be transformed to sedimentary organic facies , which is used as quantitative evaluation means if research being perfect.Now, there are many models in terms of structure either for coal or for kerogen. In our opinion, whatever coal or kerogen ought be polymer, then we follow Combaz’s thought and study structure of amorphous kerogens which are accordance with genetic mechanism showing biochemical and geochemical process perfectly. Here, we use the time of flight secondary ion mass spectrometry (TOFSIMS) to expand Combaz’s models from three to five. They are also models for coal. 展开更多
关键词 source rock classification organic ingredient classification basic structure for coal/kerogen time of flight secondary ion mass spectrometry (TOFSIMS)
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A comprehensive classification method for VOC emission sources to tackle air pollution based on VOC species reactivity and emission amounts 被引量:41
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作者 Guohao Li Wei Wei +4 位作者 Xia Shao Lei Nie Hailin Wang Xiao Yan Rui Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第5期78-88,共11页
In China, volatile organic compound(VOC) control directives have been continuously released and implemented for important sources and regions to tackle air pollution. The corresponding control requirements were base... In China, volatile organic compound(VOC) control directives have been continuously released and implemented for important sources and regions to tackle air pollution. The corresponding control requirements were based on VOC emission amounts(EA), but never considered the significant differentiation of VOC species in terms of atmospheric chemical reactivity. This will adversely influence the effect of VOC reduction on air quality improvement. Therefore,this study attempted to develop a comprehensive classification method for typical VOC sources in the Beijing–Tianjin–Hebei region(BTH), by combining the VOC emission amounts with the chemical reactivities of VOC species. Firstly, we obtained the VOC chemical profiles by measuring 5 key sources in the BTH region and referencing another 10 key sources, and estimated the ozone formation potential(OFP) per ton VOC emission for these sources by using the maximum incremental reactivity(MIR) index as the characteristic of source reactivity(SR). Then, we applied the data normalization method to respectively convert EA and SR to normalized EA(NEA) and normalized SR(NSR) for various sources in the BTH region.Finally, the control index(CI) was calculated, and these sources were further classified into four grades based on the normalized CI(NCI). The study results showed that in the BTH region,furniture coating, automobile coating, and road vehicles are characterized by high NCI and need to be given more attention; however, the petro-chemical industry, which was designated as an important control source by air quality managers, has a lower NCI. 展开更多
关键词 VOC source chemical profile source classification Beijing-Tianjin-Hebei (BTH) region
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Research on Classification of Malware Source Code
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作者 陈嘉玫 赖谷鑫 《Journal of Shanghai Jiaotong university(Science)》 EI 2014年第4期425-430,共6页
In the face threat of the Internet attack, malware classification is one of the promising solutions in the field of intrusion detection and digital forensics. In previous work, researchers performed dynamic analysis o... In the face threat of the Internet attack, malware classification is one of the promising solutions in the field of intrusion detection and digital forensics. In previous work, researchers performed dynamic analysis or static analysis after reverse engineering. But malware developers even use anti-virtual machine(VM) and obfuscation techniques to evade malware classifiers. By means of the deployment of honeypots, malware source code could be collected and analyzed. Source code analysis provides a better classification for understanding the purpose of attackers and forensics. In this paper, a novel classification approach is proposed, based on content similarity and directory structure similarity. Such a classification avoids to re-analyze known malware and allocates resources for new malware. Malware classification also let network administrators know the purpose of attackers. The experimental results demonstrate that the proposed system can classify the malware efficiently with a small misclassification ratio and the performance is better than virustotal. 展开更多
关键词 MALWARE source code classification static analysis HONEYPOT
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Quantifying the characteristics of particulate matters captured by urban plants using an automatic approach 被引量:3
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作者 Jingli Yan Lin Lin +2 位作者 Weiqi Zhou Lijian Han Keming Ma 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第1期259-267,共9页
It is widely accepted that urban plant leaves can capture airborne particles. Previous studies on the particle capture capacity of plant leaves have mostly focused on particle mass and/or size distribution. Fewer stud... It is widely accepted that urban plant leaves can capture airborne particles. Previous studies on the particle capture capacity of plant leaves have mostly focused on particle mass and/or size distribution. Fewer studies, however, have examined the particle density, and the size and shape characteristics of particles, which may have important implications for evaluating the particle capture efficiency of plants, and identifying the particle sources. In addition, the role of different vegetation types is as yet unclear. Here, we chose three species of different vegetation types, and firstly applied an object-based classification approach to automatically identify the particles from scanning electron microscope(SEM)micrographs. We then quantified the particle capture efficiency, and the major sources of particles were identified. We found(1) Rosa xanthina Lindl(shrub species) had greater retention efficiency than Broussonetia papyrifera(broadleaf species) and Pinus bungeana Zucc.(coniferous species), in terms of particle number and particle area cover.(2) 97.9% of the identified particles had diameter ≤10 μm, and 67.1% of them had diameter ≤2.5 μm. 89.8% of the particles had smooth boundaries, with 23.4% of them being nearly spherical.(3) 32.4%–74.1% of the particles were generated from bare soil and construction activities, and 15.5%–23.0% were mainly from vehicle exhaust and cooking fumes. 展开更多
关键词 Particulate matter retention Urban vegetation Object-based classification Size and shape characteristics source identification
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