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冀东太古宙表壳岩的地层划分及形成环境──冀东太古宙地质问题讨论之一 被引量:5
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作者 王启超 张少卿 齐鸿烈 《华北地质矿产杂志》 1994年第1期47-64,共18页
由于高级变质区的复杂性,因此对区内太古字的划分众说纷坛。在恢复变质岩原岩的基础上,论证了新的地层及时代划分方案,包括古(早)太古代曹庄群(时限为3600~3200Ma)、中太古代迁西群(包括早期的下亚群水厂表壳岩,时... 由于高级变质区的复杂性,因此对区内太古字的划分众说纷坛。在恢复变质岩原岩的基础上,论证了新的地层及时代划分方案,包括古(早)太古代曹庄群(时限为3600~3200Ma)、中太古代迁西群(包括早期的下亚群水厂表壳岩,时限为3200~3000Ma及晚期的上亚群太平寨表壳岩,时限为3000~2800Ma)、新(晚)太古代早期的遵化群(2800~2650Ma)与晚期的双山子群(原滦县群,相当下亚群〕、朱丈子群(二者的时限为2650~2450Ma)。利用岩石化学、微量元素、稀土元素分析广太古宇的变火山岩系列,认为均属沟、弧盆的生成环境,曹庄群属于稳定单陆屑建造。生成于冒地槽环境(沉积第一阶段);迁西群至朱丈子群为非稳定型杂陆屑建造。参照听伴生的火山岩的地化成果,进一步划分中太古代属于岛内至岛前盆地的海进层序(第二沉积阶段)及新太占代各群白早而晚为孤前、孤内至孤后盆地的海退层序(第三沉积阶段)。 展开更多
关键词 太古宙 表壳岩 地层划分 形成环境
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Regional Oceanic Impact on Circulation and Direct Radiative Effect of Aerosol over East Asia 被引量:1
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作者 XIONG Zhe HAN Zhi-Wei 《Atmospheric and Oceanic Science Letters》 2011年第6期324-329,共6页
The Regional Integrated Environmental Model System (RIEMS 2.0) coupled with a chemistry-aerosol model and the Princeton Ocean Model (POM) is employed to simulate regional oceanic impact on atmospheric circulation ... The Regional Integrated Environmental Model System (RIEMS 2.0) coupled with a chemistry-aerosol model and the Princeton Ocean Model (POM) is employed to simulate regional oceanic impact on atmospheric circulation and the direct radiative effect (DRE) of aerosol over East Asia. The aerosols considered in this study include both major anthropogenic aerosols (e.g., sulfate, black carbon, and organic carbon) and natural aerosols (e.g., soil dust and sea salt). The RIEMS 2.0 is driven by NCEP/NCAR reanalysis II, and the simulated period is from 1 January to 31 December 2006. The results show the following: (1) The simulated annual mean sea-level pressure by RIEMS 2.0 with POM is lower than without POM over the mainland and higher without POM over the ocean. (2) In summer, the subtropical high simulated by RIEMS 2.0 with POM is stronger and extends further westward, and the continental low is stronger than without POM in summer. (3) The aerosol optical depth (AOD) simulated by RIEMS 2.0 with POM is larger in the middle and lower reaches of the Yangtze River than without POM. (4) The direct radiative effect with POM is stronger than that without POM in the middle and lower reaches of the Yangtze River and parts of southern China. Therefore, the authors should take account of the impact of the regional ocean model on studying the direct climate effect &aerosols in long term simulation. 展开更多
关键词 aerosols direct radiative effect circulation regional ocean model the Regional Integrated environ- mental Model System 2.0
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Identification and evolution of tectonic units in the Philippine Sea Plate
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作者 Tian-yu Zhang Pan-feng Li +4 位作者 Lu-ning Shang Jing-yi Cong Xia Li Yong-jian Yao Yong Zhang 《China Geology》 2022年第1期96-109,共14页
The Philippine Sea Plate is located at the convergence zone of the Eurasian Plate,the Pacific Plate,and the Indo-Australian Plate.This paper divides the Philippine Sea Plate into two second-order tectonic units and ei... The Philippine Sea Plate is located at the convergence zone of the Eurasian Plate,the Pacific Plate,and the Indo-Australian Plate.This paper divides the Philippine Sea Plate into two second-order tectonic units and eight third-order tectonic units by summarizing the marine geological,geophysical,and submarine geomorphological data of the Philippine Sea Plate collected for years and referring to the seafloor spreading theory and the trench-arc-basin system.The two second-order tectonic units are the West Philippine Sea block and the Izu-Bonin-Mariana arc-basin system.The former includes the West Philippine Basin,the Huatung Basin,the Daito Basin,and the Palau Basin,while the latter consists of the Kyushu-Palau Ridge,the Shikoku-Parece Vela Basin,the Izu-Bonin Arc,and the Mariana Arc.Furthermore,this study concludes that the Philippine Sea Plate has undergone three stages of tectonic evolution,namely the early stage of the evolution of marginal basins with Cretaceous basement(Early Cretaceous),the middle stage of the spreading of the West Philippine Basin(Eocene),and the late stage of the subduction of the Izu-Bonin-Mariana arc-basin system(Oligocene-present).The Kyushu-Palau Ridge is a window to discover the tectonic evolution of the Philippine Sea Plate due to its unique geographical location. 展开更多
关键词 Philippine Sea Plate Tectonic unit Tectonic evolution trench-arc-basin system Kyushu-Palau Ridge Izu-Bonin-Mariana arc Marine scientific survey
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Crustal and upper mantle structure and the deep seismogenic environment in the source regions of the Lushan earthquake and the Wenchuan earthquake 被引量:38
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作者 ZHENG Yong GE Can +3 位作者 XIE ZuJun YANG YingJie XIONG Xiong HSU HouTze 《Science China Earth Sciences》 SCIE EI CAS 2013年第7期1158-1168,共11页
Following the M w 7.9 Wenchuan earthquake, the M w 6.6 Lushan earthquake is another devastating earthquake that struck the Longmenshan Fault Zone (LFZ) and caused severe damages. In this study, we collected continuous... Following the M w 7.9 Wenchuan earthquake, the M w 6.6 Lushan earthquake is another devastating earthquake that struck the Longmenshan Fault Zone (LFZ) and caused severe damages. In this study, we collected continuous broadband ambient noise seismic data and earthquake event data from Chinese provincial digital seismic network, and then utilized ambient noise tomography method and receiver function method to obtain high resolution shear wave velocity structure, crustal thickness, and Poisson ratio in the earthquake source region and its surroundings. Based on the tomography images and the receiver function results, we further analyzed the deep seismogenic environment of the LFZ and its neighborhood. We reveal three main findings: (1) There is big contrast of the shear wave velocities across the LFZ. (2) Both the Lushan earthquake and the Wenchuan earthquake occurred in the regions where crustal shear wave velocity and crustal thickness change dramatically. The rupture faults and the aftershock zones are also concentrated in the areas where the lateral gradients of crustal seismic wave speed and crustal thickness change significantly, and the focal depths of the earthquakes are concentrated in the transitional depths where shear wave velocities change dramatically from laterally uniform to laterally non-uniform. (3) The Wenchuan earthquake and its aftershocks occurred in low Poisson ratio region, while the Lushan earthquake sequences are located in high Poisson ratio zone. We proposed that the effect of the dramatic lateral variation of shear wave velocity, and the gravity potential energy differences caused by the big contrast in the topography and the crustal thickness across the LFZ may constitute the seismogenic environment for the strong earthquakes in the LFZ, and the Poisson ratio difference between the rocks in the south and north segments of the Longmenshan Fault zone may explain the 5 years delay of the occurrence of the Lushan earthquake than the Wenchuan earthquake. 展开更多
关键词 Lushan earthquake Wenchuan earthquake receiver function ambient noise tomography deep seismogenic environ-ment
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Operational characteristics of mixed traffic flow under bi-directional environment using cellular automaton 被引量:6
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作者 Zhenke Luo Yue Liu Chen Guo 《Journal of Traffic and Transportation Engineering(English Edition)》 2014年第6期383-392,共10页
Mixed traffic flow composed of autos and non-autos widely exists in developing countries and areas. To investigate the operational characteristics of the mixed traffic flow consisting of vehicles in different types (... Mixed traffic flow composed of autos and non-autos widely exists in developing countries and areas. To investigate the operational characteristics of the mixed traffic flow consisting of vehicles in different types (large vehicles, cars, and bicycles), we develop a cellular automaton model to repli- cate the travel behaviors on a bi-directional road segment with respect to the physical and mechanic features of different vehicle types. By implementing the essential parameters calibrated through the field data collection, a numerical study is carried out considering the variation in volume, density, and velocity with different compositions of mixed traffic flows. The primary findings include: the average ve- locity of traffic flow and total volume decrease 60% and 30% after incorporating 10% bicycles, respectively; the phenomenon of double-summit in terms bicycle is beyond 60 % ; the maximal total volume higher than 10 %. of the total volume appears when the proportion of starts to recover when the proportion of bicycle is 展开更多
关键词 mixed traffic flow operational characteristic cellular automaton bi-directional environ-ment
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Addressing the environmental risk of persistent organic pollutants in China 被引量:5
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作者 Bin WANG Jun HUANG +2 位作者 Shubo DENG Xiaoling YANG Gang YU 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2012年第1期2-16,共15页
The Stockholm Convention on persistent organic pollutants (POPs) was adopted in 2001. This year is the 10th anniversary of the adoption of the Convention. Until now, 22 chemicals or chemical categories have been lis... The Stockholm Convention on persistent organic pollutants (POPs) was adopted in 2001. This year is the 10th anniversary of the adoption of the Convention. Until now, 22 chemicals or chemical categories have been listed as POPs in the Stockholm Convention. The POPs Research Center was established in Tsinghua University in the same year when the Convention was adopted. In the last ten years, much work has been done by Chinese researchers to understand the environ- mental risk of POPs in China. This article aims to review the recent research progress of our POPs Research Center and some other Chinese researchers' studies in addressing the environmental risk of POPs, including the priority screening and inventory study of POPs, monitoring and modeling of POPs pollution and exposure, and environ- mental risk assessment and modeling of POPs. Although great advances in addressing the environmental risk of POPs have been made in recent years, we are still facing quite a few problems, such as data scarcity and uncertainty in environmental risk assessment of POPs. The study on the effect of POPs mixtures is in its infancy and currently POPs are usually assessed from legal perspective by risk assessment of single chemicals. These problems should be well addressed by further efforts. Further studies should also be taken in future to study environment risk of POPs by considering aspects of coupled dynamics between climate processes and POPs. Such sound scientific, riskbased information can support decision-making aiming to effectively minimize the risk level of POPs. 展开更多
关键词 persistent organic pollutant (POPs) environ- mental risk assessment INVENTORY environmental monitoring fugacity model emerging POPs
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Improvement of thermal environment and reduction of energy consumption for coolin8 and heating by retrofitting windows 被引量:1
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作者 Mochidome Takashi Hokoi Shuichi +2 位作者 Ogura Daisuke Takamura Masahiko Suzuki Jun 《Frontiers of Architectural Research》 CSCD 2013年第1期1-10,共10页
Various techniques for creating a comfortable thermal environment and saving energy have been proposed and employed in residential buildings in many countries, including Japan. For these techniques to be introduced, e... Various techniques for creating a comfortable thermal environment and saving energy have been proposed and employed in residential buildings in many countries, including Japan. For these techniques to be introduced, existing houses should be renovated. Among the techniques available, installation of additional inner windows is effective in creating a comfortable and energy-efficient living environment. In the present research, the effect of additional inner windows on the thermal environment and energy saving was investigated by measuring indoor climates. Windows were renovated in two rooms on the fourth floor of a four-story reinforced concrete building. Air temperatures, the humidity, the global solar radiation on horizontal and vertical surfaces, radiant temperatures, and the electricity consumption of air-conditioners were measured. A comparison of these vatues before and after the installation of inner- windows showed that the thermal environment and energy saving had improved. Results obtained from a thermal model agreed well with measured results by changing the value of solar transmittance and heat transmission coefficient of the glazing forlowing renovation. Furthermore, in a questionnaire survey conducted in summer, more than half of the occupants answered "cornfortabte" to a question on the overall thermal comfort. 展开更多
关键词 Double-skin windows Retrofitting windows Thermat environ-ment Energy saving
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Thermal physiological response to local heating and cooling during sleep 被引量:1
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作者 Yu Hibino Shuichi Hokoi +3 位作者 Katsuaki Yoshida Satoru Takada Masanori Nakajima Miho Yamate 《Frontiers of Architectural Research》 CSCD 2012年第1期51-57,共7页
For a healthy and productive life, good steep is essential, which has prompted studies on how comfortable sleep can be achieved. Understanding the relationship between thermal environment and physiological responses s... For a healthy and productive life, good steep is essential, which has prompted studies on how comfortable sleep can be achieved. Understanding the relationship between thermal environment and physiological responses such as skin and core temperatures, and psychological responses such as thermal and sleep sensations is necessary to identify the most suitable thermal environment for steep. As an energy-saving and practical method of creating the most appropriate thermal environment for sleep, local heating or cooling is sometimes used, which takes into consideration the differences in local thermal responses. We performed this study to identify the most effective thermal environment for inducing comfortable sleep by identifying the physiological responses during sleep on the basis of sleep experiments conducted under local body heating or cooling conditions. We also used a human thermal model, which can be applied for predicting physiological responses. In the experiments, the feet of the subject were the primary area to be heated or cooled, which was achieved by installing a flexible duct with an outlet placed close to the subject's feet and inlet connected to an air conditioner. Differences in the fluctuation of body temperature and sleep stage depended on the airflow direction from the duct to the feet. When air was blown downward towards the feet, body temperature decreased and the subject was able to sleep well. Measured skin and core temperatures were calculated using an improved 27-node human thermal model that was originally developed for use in subjects who are not in steep. Although skin 展开更多
关键词 SLEEP Thermal environ-ment Local air conditioning Physiologicalresponse Human thermal mode[
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The MAP/PH/N Retrial Queue in a Random Environment 被引量:1
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作者 Gang YANG Luo-gen YAO Zi-sheng OUYANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2013年第4期725-738,共14页
We consider the MAP/PH/N retrial queue with a finite number of sources operating in a finite state Markovian random environment. Two different types of multi-dimensional Markov chains are investigated describing the b... We consider the MAP/PH/N retrial queue with a finite number of sources operating in a finite state Markovian random environment. Two different types of multi-dimensional Markov chains are investigated describing the behavior of the system based on state space arrangements. The special features of the two formulations are discussed. The algorithms for calculating the stationary state probabilities are elaborated, based on which the main performance measures are obtained, and numerical examples are presented as well. 展开更多
关键词 retrial queue Markovian arrival process (MAP) phase-type service Markovian random environ-ment finite number of sources
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Enhancement of Quantum Correlations in Qubit-Qutrit Systems under the non-Markovian Environment
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作者 Abdul Basi Hamad Ali +1 位作者 Fazal Badshah Guo-Qin Ge 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第7期29-34,共6页
We investigate the time evolution of quantum correlations of a hybrid qubit-qutrit system under the classical Ornstein-Uhlenbeck(OU) noise. Here we consider two different one-parameter families of qubit-qutrit states ... We investigate the time evolution of quantum correlations of a hybrid qubit-qutrit system under the classical Ornstein-Uhlenbeck(OU) noise. Here we consider two different one-parameter families of qubit-qutrit states which independently interact with the non-Markovian reservoirs. A comparison with the Markovian dynamics reveals that for the same set of initial condition parameters, the non-Markovian behavior of the environment plays an important role in the enhancement of the survival time of quantum correlations. In addition, it is observed that the non-Markovian strength(γ/Γ) has a positive impact on the correlations time. For the initial separable states it is found that there is a finite time interval in which the geometric quantum discord is frozen despite the presence of a noisy environment and that interval can be further prolonged by using the non-Markovian property. Moreover, its decay can be significantly delayed. 展开更多
关键词 ENTANGLEMENT geometric quantum discord Ornstein-Uhlenbeck noise non-Markovian environ-ment
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Analysis of the current situation of environmental policy of China and establishment of distributed environmental policy framework
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作者 Chaoyang FU Wangfeng LI 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2015年第2期310-316,共7页
In this study, China's current macro-environ- mental policies as well as their implementation and management tools are analyzed. By using the basic economic methodology, detailed studies are conducted focusing on the... In this study, China's current macro-environ- mental policies as well as their implementation and management tools are analyzed. By using the basic economic methodology, detailed studies are conducted focusing on the implementation effect of contemporary China's typical environmental policy of the total pollutant discharge quantity control type, and also the two types of environmental management tools are compared from the perspective of implementation costs and policy uncertainty. By introduction of distributed management tools into the implementation of environmental policies, marketoriented means and the methods of economic analysis are introduced into environmental policy decision-making mechanisms, which could afford a new method for changing the current relatively low efficiency of environ- mental policy, solving the problem of"government failure" in environmental policy implementation, and providing a new way to make environmental policy system more flexible and more efficient. It is of great practical significance to solve China's current structural, complex and accumulative environmental problems. 展开更多
关键词 environmental policy distributed environ-ment policy distributed parameter model lumped para-meter model
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The influencing factors of the WTP for the risk reduction of chemical industry accidents in China
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作者 Lei HUANG Zhijuan SHAO +3 位作者 Weiliang BAO Bailing DUAN Jun BI Zengwei YUAN 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2012年第6期860-868,共9页
To explore the factors that influence respon- dents' willingness to pay (WTP) for the risk reduction of chemical industry accidents, a questionnaire survey combined with contingent valuation and psychometric paradi... To explore the factors that influence respon- dents' willingness to pay (WTP) for the risk reduction of chemical industry accidents, a questionnaire survey combined with contingent valuation and psychometric paradigm methods were conducted in the city of Yancheng, Jiangsu Province, China. Both traditional socioeconomic variables and perceived characteristics of the hazards were considered in this study, and a Tobit model was used to find the factors influencing WTP under three risk reduction scenarios. The results showed that three demographic characteristics, age, gender, and income, significantly affected the WTP for chemical risk reduction. In addition, three extracted public risk perception factors, effect, knowledge, and trust, also strongly affected the WTP. The mean WTP value increased as the magnitude of the risk reduction increased. The number of factors influencing the WTP decreased as the reduction level improved, and only the effect factor had a significant influence on the WTP for a higher level (80%) of risk reduction. The cost for chemical safety management of Yancheng was calculated, and the optimized risk reduction level was determined. These findings can assist governments and policy makers to formulate suitable strategies for risk control, to reach target groups of people to develop effective communication, and to provide specific refer- ences for the best investment for the security of local residents. 展开更多
关键词 risk perception willingness to pay contingentvaluation method risk management school of the environ-ment
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