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Effect of different cold air intensities and their lagged effects on outpatient visits for respiratory illnesses in Handan in different seasons 被引量:1
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作者 Xingshan Zhang Guiqin Fu +4 位作者 Liang Zhao Ji Wang Caimeng Liang Juanhuai Wang Meng Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第1期39-44,共6页
本文利用2016年到2019年邯郸市气象要素和呼吸系统疾病门诊数据,分析了不同季节不同强度的冷空气过程及其对呼吸系统疾病的影响,结果显示:尽管呼吸系统疾病在冬季高发,夏季最低,但冷空气对呼吸系统疾病的影响在夏,春季最大,就诊人数分... 本文利用2016年到2019年邯郸市气象要素和呼吸系统疾病门诊数据,分析了不同季节不同强度的冷空气过程及其对呼吸系统疾病的影响,结果显示:尽管呼吸系统疾病在冬季高发,夏季最低,但冷空气对呼吸系统疾病的影响在夏,春季最大,就诊人数分别在冷空气日后两天和五天增加18.4%和13.3%,而冬季就诊人数在冷空气日后三天仅增加3.2%.冷空气对疾病影响的滞后时间在夏,秋和冬季随冷空气强度的增加而减少,而春季的滞后时间总是很长.这些发现可为科学应对气候异常导致的人群健康风险提供针对性依据. 展开更多
关键词 冷空气过程 降温幅度 呼吸系统疾病 滞后效应
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Artificial ground freezing of underground mines in cold regions using thermosyphons with air insulation
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作者 Ahmad F.Zueter Mohammad Zolfagharroshan +1 位作者 Navid Bahrani Agus P.Sasmito 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第5期643-654,共12页
Current practice of underground artificial ground freezing(AGF)typically involves huge refrigeration systems of large economic and environmental costs.In this study,a novel AGF technique is proposed deploying availabl... Current practice of underground artificial ground freezing(AGF)typically involves huge refrigeration systems of large economic and environmental costs.In this study,a novel AGF technique is proposed deploying available cold wind in cold regions.This is achieved by a static heat transfer device called thermosyphon equipped with an air insulation layer.A refrigeration unit can be optionally integrated to meet additional cooling requirements.The introduction of air insulation isolates the thermosyphon from ground zones where freezing is not needed,resulting in:(1)steering the cooling resources(cold wind or refrigeration)towards zones of interest;and(2)minimizing refrigeration load.This design is demonstrated using well-validated mathematical models from our previous work based on two-phase enthalpy method of the ground coupled with a thermal resistance network for the thermosyphon.Two Canadian mines are considered:the Cigar Lake Mine and the Giant Mine.The results show that our proposed design can speed the freezing time by 30%at the Giant Mine and by two months at the Cigar Lake Mine.Further,a cooling load of 2.4 GWh can be saved at the Cigar Lake Mine.Overall,this study provides mining practitioners with sustainable solutions of underground AGF. 展开更多
关键词 Artificial ground freezing Underground mining Sustainable mining theRMOSYPHON air insulation cold regions
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Analysis of a Large Scale Cold Air Weather Process in China during January 2021
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作者 Baojun Wu 《Journal of Geoscience and Environment Protection》 2023年第9期54-63,共10页
This study uses data provided by the National Meteorological Information Center of China, Japan Meteorological Agency (JMA) and National Oceanic Atmospheric Administration (NOAA) Physical Sciences Laboratory of the US... This study uses data provided by the National Meteorological Information Center of China, Japan Meteorological Agency (JMA) and National Oceanic Atmospheric Administration (NOAA) Physical Sciences Laboratory of the USA to analyze a cold air weather process at the beginning of January 2021. Synoptic analysis is mainly used to summarize synoptic laws or patterns based on observational data, and describe and infer weather processes. The main conclusions are as follows: The cold air travels south along the northwest path, affecting most of China. During the cold wave process, the first cold air is weak, which has a certain cooling effect on northern China. The second cold air was guided by the low vortex, the accumulation in the transverse groove of Mongolia was strengthened, and the cooling effect was significant. The southwest jet showed an increasing trend, and the water vapor transport conditions were good. However, due to the relatively gentle southern branch system, the warm and humid air flow was weak and the precipitation level was small. The purpose of this study is to better understand a large-scale cold air weather process in January 2021 in China. 展开更多
关键词 cold air South Branch System Low Vortex Atmospheric Circulation
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Formation of diffuse and spark discharges between two needle electrodes with the scattering of particles
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作者 Victor F TARASENKO Dmitry V BELOPLOTOV +1 位作者 Alexei N PANCHENKO Dmitry A SOROKIN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期32-39,共8页
The development of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark decay.Positive and ... The development of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark decay.Positive and negative nanosecond voltage pulses with an amplitude of tens of kilovolts were applied.Time-resolved images of the discharge development were taken with a fourchannel Intensified Charge Coupled Device(ICCD)camera.The minimum delay between the camera channels could be as short as≈0.1 ns.This made it possible to study the gap breakdown process with subnanosecond resolution.It was observed that a wide-diameter streamer develops from the high-voltage pointed electrode.The ionization processes near the grounded pin electrode started when the streamer crossed half of the gap.After bridging the gap by the streamer,a diffuse discharge was formed.The development of spark leaders from bright spots on the surface of the pointed electrodes was observed at the next stage.It was found that the rate of development of the spark leader is an order of magnitude lower than that of the wide-diameter streamer.Long thin luminous tracks were observed against the background of a discharge plasma glow.It has been established that the tracks are adjacent to brightly glowing spots on the electrodes and are associated with the flight of small particles. 展开更多
关键词 needle electrodes short voltage pulses atmospheric air streamer breakdown diffuse and spark discharges scattering metal particles
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Analysis of Cold Air and Precipitation in Central and Eastern China, 2-5 October, 2022
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作者 Ming Shi 《Journal of Geoscience and Environment Protection》 2023年第7期205-212,共8页
This paper used potential height field data published by the China National Climate Center and the US NCEP reanalysis data. A study was conducted on a strong cold wave weather process in central and eastern China from... This paper used potential height field data published by the China National Climate Center and the US NCEP reanalysis data. A study was conducted on a strong cold wave weather process in central and eastern China from October 2 to 5, 2022. The results show that this weather process is a cold air weather process of “horizontal trough to vertical” type from the east of Novaya Zemlya Island. Cold air passes through Russia and Mongolia south, controlling northern China. The precipitation process is caused by the combination of high-altitude trough, ground front, warm and humid air flow, and precipitation weather formed by the influence of warm and humid air due to the 700 hPa shear line. The northern Sichuan Basin and the middle and lower reaches of the Yellow River in China can precipitate almost 50 mm. Water vapor is transported from the South China Sea to central and eastern China by the southwest warm and humid air flow along the west side of the West Pacific Subtropical High. Water vapor is concentrated over the precipitation area through horizontal convergence and is the most important source of water vapor causing precipitation. 展开更多
关键词 METEOROLOGICAL METHOD PRECIPITATION cold Wave cold air
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The effect of living environment on developmental disorders in cold regions
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作者 Yue Liu Yongchen Wang 《Frigid Zone Medicine》 2023年第1期22-29,共8页
Developmental disorders(DDs)are a kind of chronic maladies,which can cause serious irreversible detriment to children’s physical and mental health.It is predominantly regulated by the interaction of environment and h... Developmental disorders(DDs)are a kind of chronic maladies,which can cause serious irreversible detriment to children’s physical and mental health.It is predominantly regulated by the interaction of environment and heredity.Cold regions are mainly located in the high latitudes of China.Their living environment is characterized by frequent cold wave,huge temperature difference,severe air pollution,high calorie diet,less exercise,smoking,drinking,etc.In recent years,substantial advances have been made in studies of the correlation between the living environment features in cold regions and the DDs.Accordingly,this article reviews the impact of the peculiar living environment of cold regions on DDs,with a view to provide fresh prevention strategies for reducing the morbidity of DDs in China cold regions by ameliorating living environment. 展开更多
关键词 developmental disorders cold region low temperature air pollution LIFESTYLE
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Some Characteristics of the Surface Boundary Layer of a Strong Cold Air Process over Southern China 被引量:2
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作者 刘熙明 程雪玲 +2 位作者 吴琼 傅敏宁 曾庆存 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第1期210-218,共9页
In southern China, cold air is a common weather process during the winter season; it can cause strong wind, sharp temperature decreases, and even the snow or freezing rain events. However, the features of the atmosphe... In southern China, cold air is a common weather process during the winter season; it can cause strong wind, sharp temperature decreases, and even the snow or freezing rain events. However, the features of the atmospheric boundary layer during cold air passage are not clearly understood due to the lack of comprehensive observation data, especially regarding turbulence. In this study, four-layer gradient meteorological observation data and one-layer, 10-Hz ultrasonic anemometer-thermometer monitoring data from the northern side of Poyang Lake were employed to study the main features of the surface boundary layer during a strong cold-air passage over southern China. The results show that, with the passage of a cold air front, the wind speed exhibits low-frequency variations and that the wind systematically descends. During the strong wind period, the wind speed increases with height in the surface layer. Regular gust packets are superimposed on the basic strong wind flow. Before the passage of cold air, the wind gusts exhibit a coherent structure. The wind and turbulent momentum fluxes are small, although the gusty wind momentum flux is slightly larger than the turbulent momentum flux. However, during the invasion of cold air, both the gusty wind and turbulent momentum fluxes increase rapidly with wind speed, and the turbulent momentum flux is larger than the gusty wind momentum flux during the strong wind period. After the cold air invasion, this structure almost disappears. 展开更多
关键词 cold air surface boundary layer gusty wind descending motion
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Electronically Controlling the System of Preheating Intake Air by Flame for Diesel Engine Cold-Start 被引量:2
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作者 杜巍 赵福堂 《Journal of Beijing Institute of Technology》 EI CAS 2003年第2期158-161,共4页
In order to improve the cold start performance of heavy duty diesel engine, electronically controlling the preheating of intake air by flame was researched. According to simulation and thermodynamic analysis about th... In order to improve the cold start performance of heavy duty diesel engine, electronically controlling the preheating of intake air by flame was researched. According to simulation and thermodynamic analysis about the partial working processes of the diesel engine, the amount of heat energy, enough to make the fuel self ignite at the end of compression process at different temperatures of coolant and intake air, was calculated. Several HY20 preheating plugs were used to heat up the intake air. Meanwhile, an electronic control system based on 8 bit micro controller unit (MCS 8031) was designed to automatically control the process of heating intake air. According to the various temperatures of coolant and ambient air, one plug or two plugs can automatically be selected to heat intake air. The demo experiment validated that the total system could operate successfully and achieve the scheduled function. 展开更多
关键词 diesel engine cold start preheating intake air electronically control
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Field experimental study on the cooling effect of mine cooling system acquiring cold source from return air 被引量:8
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作者 Guo Pingye Chen Chen 《International Journal of Mining Science and Technology》 SCIE EI 2013年第3期453-456,共4页
With the increase of mining depth, more and deeper coal mines are limited by heat disaster. The cooling energy in deep mine cooling system comes from mine water inrush or ground cooling tower, but we cannot adopt the ... With the increase of mining depth, more and deeper coal mines are limited by heat disaster. The cooling energy in deep mine cooling system comes from mine water inrush or ground cooling tower, but we cannot adopt the two methods because mine water inrush in many old coal mines in China is limited. What is more, the cooling pipelines cannot be put in narrow pit-shaft. To settle the problem above, according to the characteristics of Zhangxiaolou Coal Mine, this paper adopts the deep mine return air as the cooling energy for deep mine cooling system. In addition, we carried out cite test to extract cold energy from return air. Through monitoring the water quantity, water temperature of cooling system and air temperature, we got the thermodynamic equilibrium parameters during the cooling energy acquisition analysis and the effect of cooling system that the temperature and humidity on working face are respectively reduced to 8-12 ℃ and 8-15% through cooling. This research offers experimental reference for deep mine cooling which lacks cooling energy. 展开更多
关键词 Heat disaster cold source Return air Cooling system
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ANALYSIS OF THE COLD AIR EFFECT ON AN EXTREME PRECIPITATION EVENT TRIGGERED BY AN INVERTED TROUGH OF TYPHOON HAIKUI(1211) 被引量:2
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作者 吴海英 陈海山 +2 位作者 曾明剑 刘安宁 王伟丽 《Journal of Tropical Meteorology》 SCIE 2015年第3期211-221,共11页
Based on intensive automatic weather station data, satellite cloud imagery, NCEP reanalyzed data, and the simulation results from mesoscale numerical models, this study analyzes the characteristics and formation mecha... Based on intensive automatic weather station data, satellite cloud imagery, NCEP reanalyzed data, and the simulation results from mesoscale numerical models, this study analyzes the characteristics and formation mechanisms of the mesoscale convection system(MCS) during the extreme precipitation event that was triggered by a weakened low-pressure inverted trough of Typhoon Haikui on August 10/2012. The results of this study show that cold air at the rear of a northeastern cold vortex creates thermodynamic conditions favorable to the development of extreme precipitation. The main body of the cold air is northward located so that the cold air invades only the middle layer of the periphery of the inverted trough. Thus, the cold air minimally affects the lower layer, which results in a vertically distributed structure of the temperature advection that augments the formation and development of convective instability stratification. In the middle troposphere, the cold air encounters the convergent, ascending, warm moist air from the low-pressure inverted trough, leading to frontogenesis. The frontogenesis enhances wind convergence which, in turn, further enhances the frontogenesis, and the positive feedback between these two forces augments the development of meso- and small-scale convection systems in the rainstorm region and its vicinity, which strengthens the upward transportation of water vapor from low layers and thickening of water vapor convergence and results in local heavy rains. 展开更多
关键词 heavy rain cold air FRONTOGENESIS mesoscale convection system(MCS)
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THE ROLE OF COLD AIR AND CHARACTERISTICS OF WATER VAPOR IN BOTH TCS NANMADOL (0428) AND IRMA (7427) MAKING LANDFALL ON CHINA IN WINTERTIME 被引量:3
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作者 何洁琳 管兆勇 +1 位作者 万齐林 王黎娟 《Journal of Tropical Meteorology》 SCIE 2010年第2期160-170,共11页
The NCEP/NCAR reanalysis data are used to investigate the role of cold air and moisture characteristics during the evolution of two cases of tropical cyclones (Nanmadol and Irma) which made landfall on China in winter... The NCEP/NCAR reanalysis data are used to investigate the role of cold air and moisture characteristics during the evolution of two cases of tropical cyclones (Nanmadol and Irma) which made landfall on China in wintertime. The results are shown as follows. (1) The East Asia trough steered the cold air into the tropical ocean in early winter. The tropical cyclones moved in opposite directions with a high moving out to sea and the enhancement of the pressure gradient at the periphery played a role in maintaining and strengthening the intensity of the storms. The intrusion of weak cold air into the low levels of the tropical cyclones strengthened them by improving the cyclonic disturbance when they were still over the warm sea surface. When the cold air was strong enough and intruded into the eyes, the warm cores were damaged and stuffed before dissipation. (2) The tropical cyclones were formed in a convergence zone of moisture flux and their development could enhance the disturbance of water vapor convergence, thus strengthening the moisture convergence zone. However, when they were outside the moisture zone, the storms could not gain sufficient water vapor and became weak. There were no belts of strong moisture transportation during the wintertime tropical cyclone processes. 展开更多
关键词 tropical cyclones cold air water vapor wintertime
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A Study on a Snowband Associated with a Coastal Front and Cold-Air Damming Event of 3-4 February 1998 along the Eastern Coast of the Korean Peninsula 被引量:1
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作者 Jae-Gyoo LEE Ming XUE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第2期263-279,共17页
A 24-h simulation with the Advanced Regional Prediction System (ARPS) nonhydrostatic model is performed for the heavy snowfall event of 3-4 February 1998 along the eastern coast of Korean Peninsula; the results are ... A 24-h simulation with the Advanced Regional Prediction System (ARPS) nonhydrostatic model is performed for the heavy snowfall event of 3-4 February 1998 along the eastern coast of Korean Peninsula; the results are used to understand the snowfall process, including why the precipitation maxima formed along the Yeongdong coastal region rather than over the mountain slope and ridge top during. The numerical simulation with a 4-kin horizontal grid spacing and 43 levels reproduces very well the narrow snowband located off the eastern Korean coast, away from, instead of over, the Yeongdong coastal mountain range. The general evolution of the snowband agrees quite well with radar observations, while the water-equivalent precipitation amount agrees reasonably well with radar precipitation estimate. The simulation results clearly show that the snow band developed due to the lifting by a coastal front that developed because of the damming of cold air against the eastern slope of the coastal mountain range. The damming was enhanced by the advection of cold air by a tow-level mountain-parallel jet from the north, formed due to geostrophic adjustment as the on-shore upslope air was decelerated by the mountain blocking. As the onshore flow weakened later due to synoptic-scale flow pattern change, the cold front propagated off shore and the precipitation dissipated. 展开更多
关键词 coastal snowfall cold air damming orographic precipitation
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Thermo sensitive TRPM8 channel and its role in cold induced airway symptoms 被引量:1
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作者 Jana Plevkova Zuzana Biringerova Silvia Gavliakova 《Open Journal of Molecular and Integrative Physiology》 2012年第1期21-26,共6页
It is generally accepted that environmental factors can significantly influence respiratory system. Cold is one of these factors. Understanding of the reaction of airways to cold air is very important tool leading to ... It is generally accepted that environmental factors can significantly influence respiratory system. Cold is one of these factors. Understanding of the reaction of airways to cold air is very important tool leading to improvement in management of cold induced rhinitis, cold induced asthma, exercise induced asthma, and exacerbation of chronic airway diseases induced by cold exposure. Despite the airways are protected against cold air by powerful heat and moisture exchanging counter current system within the nose, they are still at the risk of onset and development of cold induced symptoms mainly if this mechanism is insufficient, exposed person hyperventilates or is breathing subfreezing air. Some of the mechanisms involved in cold air induced reactions are understood quite well, but some of them are still discussed as they have not been satisfactorily explained, yet. Most discussed mechanisms by which cold air may induce respiratory symptoms include direct cooling and exsiccation of mucosal surface with subsequent hyper-tonicity of superficial fluid layer and interactions between the trigeminal and the vagus nerve at the central level. Molecular background for such a reaction may rely on the presence of thermo sensitive channels, mainly TRPM8, expressed on airway afferent nerves, which initiate response to cold air, giving a rise to autonomic responses like bronchoconstriction, cough, dyspnoea, chest tightness, mucus secretion and mucosal swelling. Identification of targets for cold action in the airway may help to identify potent antagonists which may prevent or reverse cold induced reactions sharing possibility for clinical application. 展开更多
关键词 cold air airWAYS thermo SENSATION TRPM8 cold HYPERTONICITY
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EFFECT OF DRY COLD AIR ACTIVITY ON THE OFFSHORE RAPID INTENSIFICATION OF SUPER TYPHOON SAOMAI(2006): A NUMERICAL SIMULATION RESEARCH
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作者 于玉斌 赵大军 陈联寿 《Journal of Tropical Meteorology》 SCIE 2016年第4期455-465,共11页
Employing the mesoscale WRF(Weather Research and Forecast) model, Super Typhoon Saomai(2006) is simulated. The variation of track and intensity and its offshore rapid intensification process are well demonstrated by t... Employing the mesoscale WRF(Weather Research and Forecast) model, Super Typhoon Saomai(2006) is simulated. The variation of track and intensity and its offshore rapid intensification process are well demonstrated by the model, and the temperature and humidity patterns associated with the dry cold air activity and their impact on and mechanism of the offshore rapid intensification of Saomai are mainly studied in this paper. The results indicate that high-resolution water vapor imagery can visually reveal the development, evolution, interaction as well as the mutual complementation of the dry cold air activity accompanied with the development of Saomai. The offshore rapid intensification phenomenon of Saomai is closely related to the dry cold air which originates from the upper- and mid-troposphere. Besides, the dry cold air from the upper troposphere is stronger than that from the mid-troposphere.Saomai intensifies as the dry cold air from the northwest moves toward its circulation but weakens when the dry cold air from the southwest is drawn into the storm. Dry cold airflows and their cold advection effect caused by the downward motion across the isentropic surface are favorable to the development of Saomai. The dry cold air always moves along an isentropic surface from the upper troposphere to the mid-troposphere around the typhoon circulation and contributes to Saomai's abrupt intensity change. 展开更多
关键词 TYPHOON rapid inTENSITY change WRF model DRY cold air
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Thermal partition of two asymmetric discrete heat sources by cold air curtain
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作者 DENG Quan-wei DENG Qi-hong 《Journal of Central South University of Technology》 2005年第z1期268-273,共6页
A partition solution implemented by a cold air curtain for two asymmetric discrete heat sources in a twodimensional rectangular enclosure was numerically studied. Main attentions were focused on the effects of Reynold... A partition solution implemented by a cold air curtain for two asymmetric discrete heat sources in a twodimensional rectangular enclosure was numerically studied. Main attentions were focused on the effects of Reynolds number, Grashof number, separation distance between heat sources, and buoyancy ratio. It is found that the airflow and heat transfer are not only determined by governing parameters, but also affected by boundary conditions. It is also found that nearly symmetry of flow structure corresponds to nearly thermal partition, and the symmetry can be enhanced when Reynolds number, separation distance and buoyancy ratio increase. In addition, it is observed that there is a minimum Reynolds number for obtaining nearly thermal partition, which increases when Grashof number increases. 展开更多
关键词 cold air CURTAin ASYMMETRIC discrete heat sources critical PARTITION REYNOLDS number mixed CONVECTION
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Analysis on the Process of a Convective Rainstorm of Stationary Front Triggered by Weak Cold Air
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作者 Jian Chen Xiakun Zhang +1 位作者 Jiayin Li Zonggui Lin 《Atmospheric and Climate Sciences》 2017年第3期382-399,共18页
Based on the conventional meteorological data and the NCEP/NCAR 1&#176 × 1&#176 reanalysis data and those related to mid-scale automatic station, satellite cloud picture and radar return, with the dynamic... Based on the conventional meteorological data and the NCEP/NCAR 1&#176 × 1&#176 reanalysis data and those related to mid-scale automatic station, satellite cloud picture and radar return, with the dynamic diagnosis analysis method, an analysis is made on the process of the convective rainstorm of quasi-stationary front triggered by the weak cold air on June 4-7, 2014, showing: 1) the process occurred in the event of convection of a stationary front triggered by the eastward moving south trough and the southward moving weak cold air from west under the background of circulation of two ridges and one trough at the Asian-European mid-high latitude and weakening and southeastward moving subtropical high;2) a system configuration that contributes to convective rainstorms formed in the event of the convergence of low-level moisture, upper-level divergence and the continuous vertical ascending motion after the 200 hPa upper-level jet stream moved westwards from east and the 850 hPa southwest jet stream intensified;3) after the intrusion by weak cold air of the meso-scale katallobaric area formed by the accumulated warm moist air of Guangxi before the intrusion, the warm moist air rose to trigger convection;convection cells developed and spread nearby the boundary between anallobaric area and katallobaric area, during which total 5 MCSs developed and each formed a rainstorm center at the part where the MCSs coincide;a meso-scale katallobaric area forms and develops 2 - 5 hours earlier than convection, so that it is also a warning of heavy rains. 展开更多
关键词 WEAK cold air STATIONARY FRONT CONVECTIVE RAinSTORM GUANGXI
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Air-sea fluxes of heat and momentum over the Yellow Sea during cold air outbreaks
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作者 WANG Jian-hong SHI Jia-lin +3 位作者 LIANG Xiang-san PENG Mo LI Zhi-jin MIAO Chun-sheng 《Marine Science Bulletin》 CAS 2019年第2期16-35,共20页
The impact of sea surface waves on air-sea fluxes of heat and momentum over the Yellow Sea caused by cold fronts during cold air outbreak(CAO)events is investigated through numerical experiments with a FVCOM-SWAVE(Fin... The impact of sea surface waves on air-sea fluxes of heat and momentum over the Yellow Sea caused by cold fronts during cold air outbreak(CAO)events is investigated through numerical experiments with a FVCOM-SWAVE(Finite-Volume Coastal Ocean Model-Surface WAVE)wave-current coupled model.Two typical types of cold fronts,i.e.,those respectively from the north and from the west,are simulated and compared to each other and with monthly mean.During cold seasons,currents in the Yellow Sea are weaker than that during warm seasons.As a result,waves show a more prominent impact.The numerical simulations suggested that both the heat and momentum fluxes are significantly enhanced during CAO events;and they could be a few times larger than the monthly average of a five-year mean.The enhancement is highly sensitive to the features of CAOs.Specifically,it depends on the cold front orientation,intensity and evolution.One mechanism that strengthens the two fluxes is via sea waves.For the CAOs that are studied,an increase in sea wave height by 50%can double the maximal momentum flux,and cause an increase in heat flux by 10-160 W/m^2. 展开更多
关键词 Yellow Sea air-sea fluxes of heat and momentum cold air outbreak sea surface wave FVCOM-SWAVE coupled model
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Effect of continuous annealing parameters on the mechanical properties and microstructures of a cold rolled dual phase steel 被引量:11
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作者 Shuang Kuang Yong-lin Kang +1 位作者 Hao Yu Ren-dong Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第2期159-164,共6页
A cold rolled dual phase (DP) steel with the C-Si-Mn alloy system was trial-produced in the laboratory, utilizing a Gleeble-3800 thermal simulator. The effects of continuous annealing parameters on the mechanical pr... A cold rolled dual phase (DP) steel with the C-Si-Mn alloy system was trial-produced in the laboratory, utilizing a Gleeble-3800 thermal simulator. The effects of continuous annealing parameters on the mechanical properties and microstructures of the DP steel were investigated by mechanical testing and microstructure observation. The results show that soaking between 760 and 820℃ for more than 80 s, rapid cooling at the rate of more than 30℃/s from the quenching temperature between 620 and 680℃, and overaging lower than 300℃ are beneficial for the mechanical properties of DP steels. An appropriate proportion of the two phases is one of the key factors for the favorable properties of DP steels. If the volume fraction of martensite and, thereby, free dislocations are deficient, the tensile strength and n value of DP steels will decrease, whereas, the yield strength will increase. But if the volume fraction of martensite is excessive to make it become a dominant phase, the yield and tensile strength will increase, whereas, the elongation will decrease obviously. When rapid cooling rate is not fast enough, pearlite or cementite will appear, which will degrade the mechanical properties. Even though martensite is sufficient, if it is decomposed in high temperature tempering, the properties will he unsatisfied. 展开更多
关键词 austenization intercritical annealing dual phase steel cold rolling DIFFUSION
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NUMERICAL STUDY OF COLD AIR IMPACT ON RAINFALL REINFORCEMENT ASSOCIATED WITH TROPICAL CYCLONE TALIM(2005):I.IMPACT OF DIFFERENT COLD AIR INTENSITY 被引量:7
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作者 董美莹 陈联寿 +2 位作者 李英 程正泉 郑沛群 《Journal of Tropical Meteorology》 SCIE 2013年第1期87-96,共10页
In 2005,significant rainfall reinforcement and severe disaster was induced by tropical cyclone(TC) Talim after it made landfall on the east of China.Observational analyses show that it has relationship with cold air i... In 2005,significant rainfall reinforcement and severe disaster was induced by tropical cyclone(TC) Talim after it made landfall on the east of China.Observational analyses show that it has relationship with cold air intrusion.For investigating the impact of cold air intensity,we make use of Weather Research and Forecasting(WRF) model,the synthesizer of NCEP/NCAR reanalysis data and Japan regional spectral model data,to carry out numerical experiments.Results show that rainfall reinforcement occurs in all experiments.Different intensity of cold air can modify the rainfall distribution and intensity significantly.In the rainfall center,the increment maximum of rainfall is twice as large as that of the minimum.Moderate cold air intrusion may result in the strongest rainfall reinforcement.Different cold air intensity can lead to different motion of low-level convergence lines and fronts.There is a good relationship between the rainfall region and the eastern part of the front.On one hand,strong cold air weakens the TC intensity by its intrusion into the TC center and results in weak convergence and a convergent zone and a rain band shifted southward.On the other hand,weak cold air reduces the convergence and moves the convergent zone and rain band northward.Moderate cold air intrusion maintains strong low-level convergence and high-level divergence,keeping strong upward motion over certain regions.Consequently,the rain band begins to stagnate and rainfall reinforces abruptly therein. 展开更多
关键词 numerical study cold air TROPICAL CYCLONE RAinFALL REinFORCEMENT
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A novel approach to regulate cell membrane permeability for ATP and NADH formation in Saccharomyces cerevisiae induced by air cold plasma 被引量:1
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作者 Xiaoyu DONG Tingting LIU Yuqin XIONG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第2期1-7,共7页
Air cold plasma has been used as a novel method for enhancing microbial fermentation. The aim of this work was to explore the effect of plasma on membrane permeability and the formation of ATP and NADH in Saccharomyce... Air cold plasma has been used as a novel method for enhancing microbial fermentation. The aim of this work was to explore the effect of plasma on membrane permeability and the formation of ATP and NADH in Saccharomyces cerevisiae, so as to provide valuable information for largescale application of plasma in the fermentation industry. Suspensions of S. cerevisiae cells were exposed to air cold plasma for 0, 1, 2, 3, 4 and 5 min, and then subjected to various analyses prior to fermentation (Oh) and at the 9 and 21 h stages of fermentation. Compared with nonexposed cells, cells exposed to plasma for 1 min exhibited a marked increase in cytoplasmic free Ca2+ concentration as a result of the significant increase in membrane potential prior to fermentation. At the same time, the ATP level in the cell suspension decreased by about 40%, resulting in a reduction of about 60% in NADH prior to culturing. However, the levels of ATP and NADH in the culture at the 9 and 21 h fermentation stages were different from the level at 0 h. Taken together, the results indicated that exposure of S. cerevisiae to air cold plasma could increase its cytoplasmic free Ca2+ concentration by improving the cell membrane potential, consequently leading to changes in ATP and NADH levels. 展开更多
关键词 Saccharomyces cerevisiae air cold plasma discharge membrane permeability
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