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Short-term Effects of Air Pollution on Mortality in a Heavily Polluted Chinese City 被引量:1
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作者 WANG Zong Shuang CHEN Ren Jie +3 位作者 WU Ji Rao KAN Hai Dong WU Gang WU Xue Fang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第8期671-674,共4页
Since the London fog in 1952, numerous epidemioLogical studies have revealed that both short-term and long-term exposure to air pollutants is associated with the development of diseases[1]. Up to date, the assessment ... Since the London fog in 1952, numerous epidemioLogical studies have revealed that both short-term and long-term exposure to air pollutants is associated with the development of diseases[1]. Up to date, the assessment of air quality on health and air quality standard establishment in developing countries were mainly relied on extrapolation based on the results from long-term cohort studies conducted in Europe and North America. 展开更多
关键词 Short-term Effects of air Pollution on Mortality in a Heavily Polluted Chinese City
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The Weather Temperature and Air Pollution Interaction and Its Effect on Hospital Admissions due to Respiratory System Diseases in Western China 被引量:5
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作者 WANG Min Zhen ZHENG Shan +2 位作者 WANG Shi Gong TAO Yan SHANG Ke Zheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第5期403-407,共5页
Air pollution has ever become a global major public health problem.Previous studies showed that air pollution is associated with excessive mortality and morbidity of respiratory disease[1-2].The extreme weather temper... Air pollution has ever become a global major public health problem.Previous studies showed that air pollution is associated with excessive mortality and morbidity of respiratory disease[1-2].The extreme weather temperature can impact human health and the thermal stresses can lead not only to direct deaths and illnesses,but also to aggravation of respiratory disease[3-4].Though the independent 展开更多
关键词 The Weather Temperature and air Pollution Interaction and Its Effect on Hospital Admissions due to Respiratory System Diseases in Western China
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Impact of Air Pollution on Community’s Health, Evidence of Industrial Zone in Masoro, Ndera Sector, Rwanda
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作者 Kagame Tonny Nsanzumukiza Martin Vincent +3 位作者 Mucyo Jean Claude Maniragaba Abias Akimanizanye Victoire Nsengimana Janvier 《Journal of Geoscience and Environment Protection》 2020年第6期47-60,共14页
Air pollution is among the leading global risks for mortality and responsible for increasing risk for chronic diseases. The aim of this study was to explore the impact of industrial zone air pollution on Masoro commun... Air pollution is among the leading global risks for mortality and responsible for increasing risk for chronic diseases. The aim of this study was to explore the impact of industrial zone air pollution on Masoro community and identify some health problems which are experienced in the communities. The key informants were selected using a purposive sampling technique and random sampling based on polluted areas. During this research, Kibagabaga hospital was consulted to identify different illness associated with air pollution in Ndera industrial zone. Respondents illustrated that a great part of emission came from industry, related activities and vehicles. The findings from the hospital illustrated that the respiratory, hypertension and diabetes dominated the illness in community due to air pollution from industrial zone, which was confirmed in this research with reference to the survey results. Air pollution is one of the greatest environmental threats and has been implicated for several adverse cardiovascular effects including arterial hypertension and diabetes. Air contamination provokes oxidative stress, systemic inflammation, and autonomic nervous system imbalance that subsequently induce endothelial dysfunction and vasoconstriction leading to increased blood pressure. The respondents confirmed that the communities are aware of pollution and experienced the consequences of pollution such as cancer and other complicated illness. 展开更多
关键词 air Pollution Community Heath Effect of air Pollution Industrial Zone
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Air breakdown induced by the microwave with two mutually orthogonal and heterophase electric field components
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作者 赵朋程 郭立新 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期577-581,共5页
The air breakdown is easily caused by the high-power microwave, which can have two mutually orthogonal and heterophase electric field components. For this case, the electron momentum conservation equation is employed ... The air breakdown is easily caused by the high-power microwave, which can have two mutually orthogonal and heterophase electric field components. For this case, the electron momentum conservation equation is employed to deduce the electric field power and effective electric field for heating electrons. Then the formula of the electric field power is introduced into the global model to simulate the air breakdown. The breakdown prediction from the global model agrees well with the experimental data. Simulation results show that the electron temperature is sensitive to the phase difference between the two electron field components, while the latter can affect obviously the growth of the electron density at low electron temperature amplitudes. The ionization of nitrogen and oxygen induces the growth of electron density, and the density loss due to the dissociative attachment and dissociative recombination is obvious only at low electron temperatures. 展开更多
关键词 high power microwave air breakdown effective electric field global model
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MFM Study:the Air Damping Effect on Magnetic Imaging of CoNbZr Thin Film
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作者 王志红 陈琨 +1 位作者 周宇 沈博侃 《Journal of Electronic Science and Technology of China》 2007年第1期50-52,共3页
This paper studies the CoNbZr soft magnetic thin film by magnetic force microscopy (MFM). By measuring in atmosphere circumstance, the magnetic force images display some clear dark dots which are corresponding to th... This paper studies the CoNbZr soft magnetic thin film by magnetic force microscopy (MFM). By measuring in atmosphere circumstance, the magnetic force images display some clear dark dots which are corresponding to the clusters in the topography images welL Then the dark dots disappear in magnetic force images, scanning in high vacuum. This indicates that the dark dots are caused by air damping between the vibrating tip and the sample. An interpretation for the above observation is given. 展开更多
关键词 air damping effect magnetic force microscopy TOPOGRAPHY magnetichnaging
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ON TEMPERATURE CHANGES OF SHANGHAI AND URBANIZATION IMPACTS
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作者 穆海振 孔春燕 +1 位作者 汤绪 柯晓新 《Journal of Tropical Meteorology》 SCIE 2009年第1期93-96,共4页
To understand how temperature varies in urban Shanghai under the background of global climate change and how it is affected by urbanization, the Shanghai temperature responses to global warming were analyzed, and then... To understand how temperature varies in urban Shanghai under the background of global climate change and how it is affected by urbanization, the Shanghai temperature responses to global warming were analyzed, and then the temperature trends of urban and suburb stations under different climatic backgrounds were obtained. The urbanization effects on temperature were studied by comparing urban stations to suburb stations, the relationship between urbanization variables and temperature components were obtained, and observation data of surface and high level were combined to assess the contribution of urbanization effect. In the last part of the paper, the cause of urbanization effects on temperature was discussed. The results indicated: The long term change trend of Shanghai annual mean temperature is 1.31/100a from 1873 to 2004, the periods of 1921 – 1948 and 1979 – 2004 are warmer, and the 1979 – 2004 period is the warmest; compared to suburb stations, the representative urban station has slower decreases in the cool period and faster increases in the warm one; the urban and suburb temperatures have distinct differences resulting from urbanization and the differences are increasing by the year, with the difference of mean temperature and minimum temperature being the greatest in fall and that of maximum temperature being the largest in summer between the urban and suburban areas. The urbanization process accelerates the warming speed, with the minimum temperature being the most obvious; the urbanization effect contributes a 0.4°C increase in 1980s and 1.1°C in 1990s to the annual mean temperature. 展开更多
关键词 climatology shanghai air temperature climate change urbanization effect
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Numerical simulation of water entry problems considering air effect using a multiphase Riemann-SPH model 被引量:3
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作者 Zi-Fei Meng Fu-Ren Ming +1 位作者 Ping-Ping Wang A-Man Zhang 《Advances in Aerodynamics》 2021年第1期244-259,共16页
The water entry is a classic fluid-structure interaction problem in ocean engineering.The prediction of impact loads on structure during the water entry is critical to some engineering applications.In this paper,a mul... The water entry is a classic fluid-structure interaction problem in ocean engineering.The prediction of impact loads on structure during the water entry is critical to some engineering applications.In this paper,a multiphase Riemann-SPH model is developed to investigate water entry problems.In this model,a special treatment,a cut-off value for the particle density,is arranged to avoid the occurrence of negative pressure.A remarkable advantage of the present multiphase SPH model is that the real speed of sound in air can be allowed when simulating water-air flows.In the present work,considering the air effect,several typical water entry problems are studied,and the evolution of multiphase interface,the motion characteristic of structure and complex fluid-structure interactions during the water entry are analyzed.Compared with the experimental data,the present multiphase SPH model can obtain satisfactory results,and it can be considered as a reliable tool in reproducing some fluid-structure interaction problems. 展开更多
关键词 Water entry Multiphase flow Fluid-structure interaction SPH air effect
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NUMERICAL EXPERIMENT WITH PROCESSES FOR EFFECT OF AUSTRALIAN COLD AIR ACTIVITY ON EAST-ASIAN SUMMER MONSOON 被引量:6
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作者 何金海 李俊 李永平 《Acta meteorologica Sinica》 SCIE 1990年第1期51-59,共9页
Based on diagnostic results,a numerical study is made of the processes of Australian cold air activity affecting East Asian summer monsoon by using Kuo-Qian P-σ incorporated coordinate five-layer primitive equation s... Based on diagnostic results,a numerical study is made of the processes of Australian cold air activity affecting East Asian summer monsoon by using Kuo-Qian P-σ incorporated coordinate five-layer primitive equation spherical band model.Analysis is done of the response to the Southern Hemisphere circulation with and without cold air activity in Australia of the flow,rainfall and diabatic heating fields in the monsoon area of Asia,especially,East Asia,with special attention to the intensification and northward march of the monsoon due to the activity.It is found that the processes for the effect transmission are very analogous to the meridional propagation of quasi-40-day oscillation,together with the meridional wind disturbance showing south-north travel and the flow/rainfall fields exhibitirg corresponding movement in this direction,only with a 12-day lag. 展开更多
关键词 NUMERICAL EXPERIMENT WITH PROCESSES FOR EFFECT OF AUSTRALIAN COLD air ACTIVITY ON EAST-ASIAN SUMMER MONSOON ASIA BAY
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Design of the Airbag Inflation System Applicable to Conventional and Autonomous Vehicles 被引量:1
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作者 Nina F.Yurchenko David S.Breed Shaowei Zhang 《Automotive Innovation》 EI CSCD 2021年第4期390-399,共10页
The emergency transformation of various aspects of life and business these days requires prompt evaluation of autonomous vehicles.One of the primary reassessments deals with the applicability of the vehicle passive sa... The emergency transformation of various aspects of life and business these days requires prompt evaluation of autonomous vehicles.One of the primary reassessments deals with the applicability of the vehicle passive safety system to the protec-tion of arbitrarily positioned passengers.To mitigate possible risks caused by the simultaneous deployment of several big airbags,a new principle of their operation is required.Herein,the aspirated inflator for a driver airbag is developed that can provide 50L-airbag inflation within 30-40 ms.As a result,about 3/4 of the air is to be entrained into an airbag from the vehicle compartment.The process is initiated by a supersonic pulse jet(1/3 air volume)generated pyrotechnically.Then the Prandtl-Meyer problem formulation enables guiding linear and angular dimensions of the essential parts of the device.Accordingly,a family of experimental models of varied geometry is fabricated and tested to determine their operational effectiveness in a range of motive pressure within~3-7 MPa.Experiments are performed on a specially designed facility equipped with compressed-air tanks and a high-speed valve to mimic the inflator operation with the pyrotechnic gas generator.The aspirated inflator operability is characterized using multivariate measurements of pressure fields,high-speed video-recording of the airbag inflation process,and evaluation of aspiration(entrainment)ratio.The average volume aspiration ratio measured at 300 K is found to reach 2.8 and it’s expected to almost double at 1200 K. 展开更多
关键词 Novel airbag system Aspirated inflator air entrainment effectiveness Experimental investigations
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A prospective study (SCOPE) comparing the cardiometabolic and respiratory effects of air pollution exposure on healthy and pre-diabetic individuals 被引量:4
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作者 Yanwen Wang Yiqun Han +2 位作者 Tong Zhu Weiju Li Hongyin Zhang 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第1期46-56,共11页
Air pollution is known to be a major risk factor for cardiopulmonary disease, but this is unclear for cardiometabolic disease (e.g.diabetes). This is of considerable public health importance, given the nationwide epid... Air pollution is known to be a major risk factor for cardiopulmonary disease, but this is unclear for cardiometabolic disease (e.g.diabetes). This is of considerable public health importance, given the nationwide epidemic of diabetes, accompanied by severe air pollution, in China. The evidence so far remained inadequate to answer questions of whether individuals with cardiometabolic dysfunctions are susceptible to air pollution and whether air pollution exacerbates diabetes development via certain biological pathways. In this manuscript, we summarize the results and limitations of studies exploring these two topics and elaborate our design of a prospective panel study (SCOPE) as a solution. We assessed and compared the health effect of air pollution among pre-diabetic individuals and matched healthy controls through four repeated clinical visits over 1 year. Comprehensive evaluation was made to both health endpoints and exposure. The primary biomarkers were assessed to reveal the impact on multiple biological pathways, including glycolipid metabolism and insulin resistance, endothelial function, and inflammation. Detailed chemical and size fractional components of particulate matter were measured in this study, along with the application of personal monitors.The work should increase our understanding of how air pollution affects individuals with cardiometabolic dysfunction and the underlying mechanisms. 展开更多
关键词 panel study air pollution diabetes susceptibility cardiometabolic effect
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Polarization effect on critical power and luminescence in an air filament 被引量:1
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作者 刘畅 臧宏伟 +2 位作者 李贺龙 于颜豪 徐淮良 《Chinese Optics Letters》 SCIE EI CAS CSCD 2017年第12期1-5,共5页
We demonstrate that the filamentation process is strongly influenced by the polarization state of the driver laser. When the laser polarization changes from linear to circular, the critical power for the self-focusing... We demonstrate that the filamentation process is strongly influenced by the polarization state of the driver laser. When the laser polarization changes from linear to circular, the critical power for the self-focusing of a Ti:Sapphire laser (800 nm, 40 fs) in air increases from about 9.6 ± 1.0 to 14.9± 1.5 GW, while the second nonlinear refractive index n2 of air decreases from 9.9 × 10-2o to 6.4 ×10-20 cm2/W. We also demonstrate that the luminescence from the neutral nitrogen molecules at 337 nm is dependent on both the laser intensity and plasma density inside the filament. 展开更多
关键词 Polarization effect on critical power and luminescence in an air filament
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Air turbulence effects on performance of optical wireless communication with crosstalk in server backplane
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作者 D.Elmakias D.Bykhovsky S.Arnon 《Chinese Optics Letters》 SCIE EI CAS CSCD 2017年第2期20-24,共5页
Free space optical interconnections(FSOIs) are anticipated to become a prevalent technology for short-range high-speed communication. FSOIs use lasers in board-to-board and rack-to-rack communication to achieve impr... Free space optical interconnections(FSOIs) are anticipated to become a prevalent technology for short-range high-speed communication. FSOIs use lasers in board-to-board and rack-to-rack communication to achieve improved performance in next generation servers and are expected to help meet the growing demand for massive amounts of inter-card data communication. An array of transmitters and receivers arranged to create an optical bus for inter-card and card-to-backplane communication could be the solution. However, both chip heating and cooling fans produce temperature gradients and hot air flow that results in air turbulence inside the server, which induces signal fading and, hence, influences the communication performance. In addition, the proximity between neighboring transmitters and receivers in the array leads to crosstalk in the received signal, which further contributes to signal degradation. In this Letter, the primary objective is to experimentally examine the off-axis crosstalk between links in the presence of turbulence inside a server chassis. The effects of geometrical and inter-chassis turbulence characteristics are investigated and first-and second-order statistics are derived. 展开更多
关键词 air turbulence effects on performance of optical wireless communication with crosstalk in server backplane
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DSMC modeling of rarefied ionization reactions and applications to hypervelocity spacecraft reentry flows 被引量:3
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作者 Ming Fang Zhi-Hui Li +2 位作者 Zhong-Hua Li Jie Liang Yong-Hao Zhang 《Advances in Aerodynamics》 2020年第1期120-144,共25页
The DSMC modeling is developed to simulate three-dimensional(3D)rarefied ionization flows and numerically forecast the communication blackout around spacecraft during hypervelocity reentry.A new weighting factor schem... The DSMC modeling is developed to simulate three-dimensional(3D)rarefied ionization flows and numerically forecast the communication blackout around spacecraft during hypervelocity reentry.A new weighting factor scheme for rare species is introduced,whose key point is to modify the corresponding chemical reaction coefficients involving electrons,meanwhile reproduce the rare species in resultants and preserve/delete common species in reactants according to the weighting factors.The resulting DSMC method is highly efficient in simulating weakly inhomogeneous flows including the Couette shear flow and controlling statistical fluctuation with high resolution.The accurate reliability of the present DSMC modeling is also validated by the comparison with a series of experimental measurements of the Shenzhou reentry capsule tested in a low-density wind tunnel from the HAI of CARDC.The obtained electron number density distribution for the RAM-C II vehicle agrees well with the flight experiment data,while the electron density contours for the Stardust hypervelocity reentry match the reference data completely.In addition,the present 3D DSMC algorithm can capture distribution of the electron,N+and O+number densities better than the axis-symmetric DSMC model.The introduction of rare species weighting factor scheme can significantly improve the smoothness of the number density contours of rare species,especially for that of electron in weak ionization case,while it has negligible effect on the macroscopic flow parameters.The ionization characteristics of the Chinese lunar capsule reentry process are numerically analyzed and forecasted in the rarefied transitional flow regime at the flying altitudes between 80 and 97 km,and the simulations predict communication blackout altitudes which are in good agreement with the actual reentry flight data.For the spacecraft reentry with hypervelocity larger than the second cosmic speed,it is forecasted and verified by the present DSMC modeling that ionization reactions will cover the windward capsule surface,leading to reentry communication blackout,and the communication interruption must be considered in the communication design during reentry in rarefied flow regimes. 展开更多
关键词 Spacecraft hypervelocity reentry Chemical reaction air ionization effect Rarefied gas dynamics DSMC method Communication blackout
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Ordering effects of cholesterol on sphingomyelin monolayers investigated by high-resolution broadband sum-frequency generation vibrational spectroscopy 被引量:1
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作者 Yiyi Li Rongjuan Feng +3 位作者 Lu Lin Minghua Liu Yuan Guo Zhen Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第3期357-360,共4页
This report investigated the ordering of the alky chain of sphingomyelin (SMs) monolayers induced by cholesterol at the air/water interface using high-resolution broadband sum frequency generation vibrational spectr... This report investigated the ordering of the alky chain of sphingomyelin (SMs) monolayers induced by cholesterol at the air/water interface using high-resolution broadband sum frequency generation vibrational spectroscopy (HR-BB-SFG-VS). The SFG spectra of the three nature sphingomyelin/cholesterol mixture monolayers with two concentrations of the cholesterol at the air/water interface are performed under different polarization combination. A new resolved CH2 symmetric stretching (d+, ~2834 cm-1) and the CH3 symmetric stretching (r+, ~2874 cm-1) mode are applied to characterize the conformational order in the sphingomyelin/cholesterol mixture monolayers. It was found that the cholesterol make the sphingosine backbones more conformational order. During this process, the conformational order of the N-linked acyl chain remains unaltered. Moreover, the sphingosine backbones of SMs have much larger contributions to gauche defects of SMs than one in the N-linked acyl chain. These results presented here not only shed lights on understanding of the interactions of sphingomyelin molecules with cholesterol molecules at interface but also demonstrates the ability of HR-BB-SFG to probe such complicated molecular systems. 展开更多
关键词 Sphingomyelin Cholesterol Ordering effect air/liquid interface High-resolution broadband sum frequency generation Vibrational spectroscopy
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NUMERICAL SIMULATION OF THE VERTICAL IMPACT OF A SUPERSONIC FLAT-HEAD BODY ON A WATER SURFACE
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作者 Li Sen-hu He You-sheng Lu Chuan-jing Shanghai Jiao Tong University,Shanghai 200030,P.R.China 《Journal of Hydrodynamics》 SCIE EI CSCD 1993年第3期1-8,共8页
By using PIC method ,the vertical impact on the water surface for a 2-D su- personic flat-head body with a detached shock wave is studied in this paper.Numerical results show that various complicated flow phenomena su... By using PIC method ,the vertical impact on the water surface for a 2-D su- personic flat-head body with a detached shock wave is studied in this paper.Numerical results show that various complicated flow phenomena such as the supersonic flow around the body,the air cushion effect,the propagation of the shock wave in water,the initial formation of the wa- ter-entry cavity and the pile-up of the water surface are simulated successfully. 展开更多
关键词 water entry IMPACT air cushion effect shock wave supersonic flow PIC method
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