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Coal mining in northeast India: an overview of environmental issues and treatment approaches 被引量:16
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作者 Mayuri Chabukdhara O. P. Singh 《International Journal of Coal Science & Technology》 EI 2016年第2期87-96,共10页
Northeast India has a good deposit of sub-bituminous tertiary coal. The northeast Indian coals have unusual physico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash cont... Northeast India has a good deposit of sub-bituminous tertiary coal. The northeast Indian coals have unusual physico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash content. In addition, many environmental sensitive organic and mineral bound elements such as Fe, Mg, Bi, AI, V, Cu, Cd, Ni, Pb, and Mn etc. remain enriched in these coals. Such characteristics are associated with more severe environmental impacts due to mining and its utilization in coal based industries. Environmental challenges include large scale landscape damage, soil erosion, loss of forest ecosystem and wildlife habitat, air, water and soil pollution. Several physical and chemical methods are reported in literature for the removal of mineral matter, total sulfur and different forms of sulfur from high sulfur coal in northeast India. This paper may help different researchers and stakeholders to understand current state of research in the field. Initiatives may be taken towards sustainable use of coal resources by adopting innovative clean technologies and by implementing effective control measures and regulatory policies. 展开更多
关键词 Northeast India Sub-bituminous coal Environmental issues Innovative technologies Management andregulatory policies
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Metamaterials: Reshape and Rethink 被引量:2
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作者 Ruopeng Liu Chunlin Ji +1 位作者 Zhiya Zhao Tian Zhou 《Engineering》 SCIE EI 2015年第2期179-184,共6页
Metamaterials are composite materials whose material properties(acoustic, electrical, magnetic, or optical, etc.) are determined by their constitutive structural materials, especially the unit cells. The development o... Metamaterials are composite materials whose material properties(acoustic, electrical, magnetic, or optical, etc.) are determined by their constitutive structural materials, especially the unit cells. The development of metamaterials continues to redefine the boundaries of materials science. In the field of electromagnetic research and beyond, these materials offer excellent design flexibility with their customized properties and their tunability under external stimuli. In this paper, we first provide a literature review of metamaterials with a focus on the technology and its evolution. We then discuss steps in the industrialization process and share our own experience. 展开更多
关键词 METAMATERIALS metasurface smart structure metadevices INDUSTRIALIZATION
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Overview on seagrasses and related research in China 被引量:4
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作者 石雅君 范航清 +3 位作者 崔晓健 潘良浩 李森 宋秀凯 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第2期329-339,共11页
Seagrass research in China is still in its infancy. Even though there has been progress recently, there is still a great deal of research needed to gain a better understanding of seagrass. In this article we review an... Seagrass research in China is still in its infancy. Even though there has been progress recently, there is still a great deal of research needed to gain a better understanding of seagrass. In this article we review and discuss the advances in seagrass research in China from two aspects: (1) seagrass species and their distribution; (2) seagrass research in China, including studies on their taxonomy, ecology, photosynthesis, applications in aquaculture, salt-tolerance mechanisms and other research topics. A total of 18 seagrass species belonging to 8 genera are distributed in nine provinces and regions in China (including Hong Kong and Taiwan), as well as the Xisha and Nansha Archipelagos. They can be divided into two groups: a North China Group and a South China Group. Based on the seagrass distribution, the Chinese mainland coast can be divided into three sections: North China Seagrass Coast, Middle China Seagrass Coast, and South China Seagrass Coast. Ecological studies include research on seagrass communities, nutrient cycling in seagrass ecosystems, genetic diversity, pollution ecology and research in the key regions of Shandong, Guangdong, Guangxi, and Hainan. Seagrass species and their locations, community structure, ecological evaluation, epiphytes, ecological functions and threats in the key regions are also summarized. Other studies have focused on remote sensing of seagrass, threatened seagrass species of China, and pollen morphology of Halophila ovalis. 展开更多
关键词 SEAGRASS seagrass meadow marine ecosystem China
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Analytical and numerical solutions for shear mechanical behaviors of structural plane
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作者 何忠明 熊喆怡 +1 位作者 胡庆国 杨明 《Journal of Central South University》 SCIE EI CAS 2014年第7期2944-2949,共6页
The original descriptive model of shear stress and shear displacement only reflects the stress deformation characteristics of plastic structural plane.The index model was revised and piecewise index model was built to... The original descriptive model of shear stress and shear displacement only reflects the stress deformation characteristics of plastic structural plane.The index model was revised and piecewise index model was built to describe the stress deformation characteristics of plastic structural plane and brittle structural plane.The relation of stress and strain to the failure mode of structural plane considering the effect of its shape was investigated,and a model which could reflect the relation between undulate angle and shear strength was built.The result indicates that structural plane presents nonlinear characteristics,specifically,the value of undulate angle,as well as corresponding shear strength,becomes larger as the normal stress decreases. 展开更多
关键词 structural plane shear mechanical behavior model failure mode nonlinear characteristics numerical analysis
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A Review on Researches of Active Tectonics—History,Progress and Suggestions 被引量:3
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作者 Deng Qidong Wen Xueze 《Earthquake Research in China》 2009年第1期1-27,共27页
This paper reviews the history and progress of research on active tectonics in China and overseas.By giving a brief introduction on the history of active tectonic research in China and other countries,the paper sums u... This paper reviews the history and progress of research on active tectonics in China and overseas.By giving a brief introduction on the history of active tectonic research in China and other countries,the paper sums up the process and development of quantitative investigation of active tectonics since the 1980s.The focus is on the main efforts and progress made in China on certain aspects of research,such as basic surveys and applied investigation of active tectonics,the study of theories related to regional active tectonics and their kinematics and geodynamics,surveys on coupling relations between deep and shallow structures,active fault surveys and prospecting and seismic hazard assessment in urban areas,as well as the efforts made using Quaternary geochronology.Furthermore,the paper looks back on Chinese quantitative investigation of active tectonics in China and sums up cognitions derived from studies on the determination of several basic and measurable parameters of active tectonics.These parameters include the length of fault and fault segmentation,coseismic slip and cumulative slip,fault slip rate,the sequence of paleoearthquake events and the time elapsed since the most recent event.At the same time,efforts and progress made in China on assessing the long-term seismic potential for active faults and evaluating the risk from potential active fault movement have been reviewed by summarizing research on developing theories,models,methods and the application of time-dependent seismic potential to probabilistic assessment,magnitude estimation for potential earthquakes on active faults,and the forecast of potential risk caused by active fault movement.Finally,in consideration of the realities and problems in the research of active tectonics in China,the authors put forward several suggestions for issues worthy of more attention for further investigation in the future. 展开更多
关键词 Active tectonics History and progress of research Quantitative investigation Problems and suggestions
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中医外治法治疗急性痛风性关节炎的研究进展 被引量:1
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作者 李熙红 王海东 《湖南中医杂志》 2012年第6期144-145,共2页
痛风(gout)为嘌呤代谢紊乱和(或)尿酸排泄障碍所致血尿酸增高的一组异质性疾病。其临床特点为高血尿酸症伴痛风性急性关节炎反复发作、痛风石沉积、痛风石性慢性关节炎和关节畸形,常累及肾脏引起慢性间质性肾炎和尿酸肾结石形成。... 痛风(gout)为嘌呤代谢紊乱和(或)尿酸排泄障碍所致血尿酸增高的一组异质性疾病。其临床特点为高血尿酸症伴痛风性急性关节炎反复发作、痛风石沉积、痛风石性慢性关节炎和关节畸形,常累及肾脏引起慢性间质性肾炎和尿酸肾结石形成。该病多见于40岁以上的男性和绝经期后的女性,主要表现为反复发作的关节红、肿、热、痛,以及痛风石形成,严重者可导致关节畸形和功能障碍,甚至损害心肾功能。 展开更多
关键词 痛风性关节炎 中医药疗法 外治法 综述 学述性
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Realistic interpretation of quantum mechanics and encounter-delayed-choice experiment 被引量:1
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作者 GuiLu Long Wei Qin +1 位作者 Zhe Yang Jun-Lin Li 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2018年第3期10-17,共8页
In this paper, a realistic interpretation(REIN) of the wave function in quantum mechanics is briefly presented. We demonstrate that in the REIN, the wave function of a microscopic object is its real existence rather t... In this paper, a realistic interpretation(REIN) of the wave function in quantum mechanics is briefly presented. We demonstrate that in the REIN, the wave function of a microscopic object is its real existence rather than a mere mathematical description.Specifically, the quantum object can exist in disjointed regions of space just as the wave function is distributed, travels at a finite speed, and collapses instantly upon a measurement. Furthermore, we analyze the single-photon interference in a Mach-Zehnder interferometer(MZI) using the REIN. Based on this, we propose and experimentally implement a generalized delayed-choice experiment, called the encounter-delayed-choice experiment, where the second beam splitter is decided whether or not to insert at the encounter of two sub-waves along the arms of the MZI. In such an experiment, the parts of the sub-waves, which do not travel through the beam splitter, show a particle nature, whereas the remaining parts interfere and thus show a wave nature. The predicted phenomenon is clearly demonstrated in the experiment, thus supporting the REIN idea. 展开更多
关键词 wave function realistic interpretation Mach-Zehnder interferometer wave-particle duality
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Achievements and Challenges: A Review of Chinese Literature on Gender and Women's Studies from 2001 to 2008
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作者 Zhu Xiao-hui 《Fudan Journal of the Humanities and Social Sciences》 2010年第2期42-63,共22页
This article explores Women's Studies through a review Database in the period 2001-2008, recent Chinese research on Gender and of the China Academic Journals Full-Text summarizing, classifying and evaluating the ma... This article explores Women's Studies through a review Database in the period 2001-2008, recent Chinese research on Gender and of the China Academic Journals Full-Text summarizing, classifying and evaluating the main areas of focus with which Chinese scholars have been concerned. The first part is concerned with Gender and Women's Studies of a distinctively Chinese character. Current Chinese social structure contains the binary framework: rural and urban. P, ural women's situations are being greatly changed since male laborers went in large numbers to work in the cities and have caused great concern among scholars. To build a "Harmomous Society," more attention has been paid to the study of gender and ethnic equality. Scholars have analyzed and discussed the remaining gender and ethnic inequalities existent in the actual society. The second part is women's lives in literary history, which were usually darkened by textual silence, despite China's rich ancient literature. To reinterpret Chinese traditional literature, discovering women's history and listening to women's voices has also become a major undertaking. The third part of the article summarizes the Chinese scholars' dilemma. On one hand, scholars have benefited from the rise of Western feminist theories; on the other hand, they are also disturbed that China's Women's Studies have been marginalized by such a strong Western feminist discourse. Chinese scholars have been trying to develop indigenous knowledge and to create a theoretical system with its focus on Chinese women, thereby breaking through the stereotype of the West versus the East or the center versus the periphery, and to communicate equally with Western scholars. 展开更多
关键词 gender and women's studies China ACHIEVEMENTS CHALLENGES
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Geostatistics for Spatial Uncertainty Characterization
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作者 ZHANG Jingxiong ZHANG Jinping YAO Na 《Geo-Spatial Information Science》 2009年第1期7-12,共6页
Most geospatial phenomena can be interpreted probabilistically because we are ignorant of the biophysical proc- esses and mechanisms that have jointly created and observed events. This philosophy is important because ... Most geospatial phenomena can be interpreted probabilistically because we are ignorant of the biophysical proc- esses and mechanisms that have jointly created and observed events. This philosophy is important because we are certain about the phenomenon under study at sampled locations, except for measurement errors, but, in between the sampled, we become uncertain about how the phenomenon behaves. Geostatistical uncertainty characterization is to generate random numbers in such a way that they simulate the outcomes of the random processes that created the existing sample data. This set of existing sample is viewed as a partially sampled realization of that random function model. The random function's spa- tial variability is described by a variogram or covariance model. The realized surfaces need to honour sample data at their lo- cations, and reflect the spatial structure quantified by the variogram models. They should each reproduce the sample histo- gram representative of the whole sampling area. This paper will review the fundamentals in stochastic simulation by covering univariate and indicator techniques in the hope that their applications in geospatial information science will be wide-spread and fruitful. 展开更多
关键词 UNCERTAINTY stochastic simulation REALIZATION normal score transform
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Application of Kinetic Models in Describing Soil Potassium Release Characteristics and Their Correlations with Potassium Extracted by Chemical Methods 被引量:8
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作者 A. R. HOSSEINPUR H. R. MOTAGHIAN 《Pedosphere》 SCIE CAS CSCD 2013年第4期482-492,共11页
Potassium (K) release characteristics in soil play a significant role in supplying available K. Information on K-release characteristics in soils of central Iran is limited. The objectives of this study were to dete... Potassium (K) release characteristics in soil play a significant role in supplying available K. Information on K-release characteristics in soils of central Iran is limited. The objectives of this study were to determine K release characteristics and correlations of K release rate constants with K extracted by different chemical methods in surface soils of ten calcareous soils of central Iran. The kinetics of K release in the soils was determined by successive extraction with 0.01 mol L-1 CaC12 in a period of 2-2017 h at 25±1℃. Soil K was extracted by distilled water, 0.5 mol L-1 MgNO3, 0.002 mol L-1 SrC12, 0.1 mol L-1 BaC12, 0.01 mol L-1 CaC12, 1 mol L-1 NaC1, 1 mol L-1 boiling HNO3, 1 mol L-1 NH4OAC, Mehlich 1, 0.002 mol L-1 SrC12 + 0.05 mol L-1 citric acid, and ammonium bicarbonate-diethylenetriamine pentaacetic acid (AB-DTPA). A plot of cumulative amounts of K released showed a discontinuity in slope at 168 h. Thus, two equations were applied to two segments of the total reaction time (2-168 and 168-2 017 h). Cumulative amounts of K released ranged from 55 to 299 mg kg-1 in 2-168 h and from 44 to 119 mg kg-1 in 168-2 017 h. Release kinetics of K in the two time segments conformed fairly well to parabolic diffusion, simplified Elovich, and power function models. There was a wide variation in the K release rate constants. Increasingly higher average concentrations of soil K were extracted by distilled water, Mehlich 1, SrC12, CaC12, SrC12 + citric acid, AB-DTPA, MgNO3, NaCI, NH4OAc, BaCI2, and HNO3. Potassium release rate constants were significantly correlated with K extracted. The results of this study showed that information obtained from mathematical modeling in two reaction time segments can help to estimate the K-supplying power of soils. 展开更多
关键词 chemical extraction calcareous soils mathematical modeling release rate constant time segments
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Effect of grain boundary on the mechanical behaviors of irradiated metals: a review 被引量:1
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作者 Xia Zi Xiao Hai Jian Chu Hui Ling Duan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第6期24-34,共11页
The design of high irradiation-resistant materials is very important for the development of next-generation nuclear reactors. Grain boundaries acting as effective defect sinks are thought to be able to moderate the de... The design of high irradiation-resistant materials is very important for the development of next-generation nuclear reactors. Grain boundaries acting as effective defect sinks are thought to be able to moderate the deterioration of mechanical behaviors of irradiated materials, and have drawn increasing attention in recent years. The study of the effect of grain boundaries on the mechanical behaviors of irradiated materials is a multi-scale problem. At the atomic level, grain boundaries can effectively affect the production and formation of irradiation-induced point defects in grain interiors, which leads to the change of density, size distribution and evolution of defect clusters at grain level. The change of microstructure would influence the macroscopic mechanical properties of the irradiated polycrystal. Here we give a brief review about the effect of grain boundaries on the mechanical behaviors of irradiated metals from three scales: microscopic scale, mesoscopic scale and macroscopic scale. 展开更多
关键词 mechanical behaviors irradiation effect grain boundary multi-scale modeling
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Parameter uncertainty in biomathematical model described by one-prey two-predator system with mutualism
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作者 D. Pal G. S. Mahapatra G. P. Samanta 《International Journal of Biomathematics》 2017年第6期147-182,共36页
In this paper, a three-species system consisting of two predators which are in mutual- ism with each other and preying on the same single prey is considered. Also, the prey and first predator are harvested under optim... In this paper, a three-species system consisting of two predators which are in mutual- ism with each other and preying on the same single prey is considered. Also, the prey and first predator are harvested under optimal conditions. The values of the biological parameters depend on the collection of data from the experts as well as on the nature of the environment in which prey predator system are considered. So the biological para- meters are not precise in reality. This paper presents a different approach to study the prey-predator model with imprecise biological parameters. All the possible equilibrium points are identified and the local as well as global stability criteria under imprecise- ness are discussed. The possibility of existence of bionomic equilibrium is discussed. The optimal harvesting policy is studied using Pontryagin's maximum principle. Numerical examples are provided to support the proposed approach. 展开更多
关键词 MUTUALISM EQUILIBRIUM stability bioeconomic optimal control intervalnumber.
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