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Analysis of Temperature Trends and Variations in the Arabian Peninsula’s Upper Atmosphere
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作者 Abdullrahman H. Maghrabi 《Atmospheric and Climate Sciences》 2024年第1期85-100,共16页
In this study, the trends of upper-air temperatures are analysed by utilising radiosonde observations for the barometric levels at 700, 500, 300, 200, 150, 100 and 50 hPa from five meteorological stations within the A... In this study, the trends of upper-air temperatures are analysed by utilising radiosonde observations for the barometric levels at 700, 500, 300, 200, 150, 100 and 50 hPa from five meteorological stations within the Arabian Peninsula from January 1986 to August 2015. The mean monthly variations of the temperatures at these levels are characterised and established. The magnitudes of the annual trends of the mean temperatures for each site for the selected barometric levels are studied and statistically tested using Mann-Kendall rank statistics at different significance levels. The temperature trends at different pressure levels show that the upper troposphere and lower stratosphere are warming, while the middle troposphere is cooling which is consistent with the findings of other studies. The variations in upper air temperature observed in this study can be attributed to a range of factors, including increasing greenhouse gas concentrations, changes in atmospheric circulation patterns, variations in solar activity, aerosols and volcanic eruptions, and land use and land cover change. 展开更多
关键词 Upper-Air temperature Variability Long-Term Trend Arabian Peninsula Climate Change Mann-Kendell
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SOLID-STATE VARIABLE-TEMPERATURE NMR STUDY ON THE PHASE SEPARATION OF POLYETHER POLYURETHANE ZWITTERIONOMERS
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作者 杨光 陈群 +2 位作者 王源身 杨昌正 邬学文 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第4期302-308,共7页
Polyether-polyurethane zwitterionomers based on 4, 4'-diphenylmethane diisocyanate(MDI), methyl diethanolamine (MDEA), and polytetramethylene oxide glycol (PTMO) werestudied with variable-temperature wide-line ~1H... Polyether-polyurethane zwitterionomers based on 4, 4'-diphenylmethane diisocyanate(MDI), methyl diethanolamine (MDEA), and polytetramethylene oxide glycol (PTMO) werestudied with variable-temperature wide-line ~1H NMR. It is found that upon ionization, degree ofphase separation in the polymer system decreased at first due to the loss of hard segmentregularity, while further ionization increased the degree of phase separation through increasinghard phase cohesion and difference of polarity between hard and soft segments. 展开更多
关键词 Polyether polyurethane variable temperature Wide-line NMR Phase separation
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On Multi-Timescale Variability of Temperature in China in Modulated Annual Cycle Reference Frame 被引量:16
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作者 钱诚 Zhaohua WU +1 位作者 符淙斌 周天军 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第5期1169-1182,共14页
The traditional anomaly (TA) reference frame and its corresponding anomaly for a given data span changes with the extension of data length. In this study, the modulated annual cycle (MAC), instead of the widely us... The traditional anomaly (TA) reference frame and its corresponding anomaly for a given data span changes with the extension of data length. In this study, the modulated annual cycle (MAC), instead of the widely used climatological mean annual cycle, is used as an alternative reference frame for computing climate anomalies to study the multi-timescale variability of surface air temperature (SAT) in China based on homogenized daily data from 1952 to 2004. The Ensemble Empirical Mode Decomposition (EEMD) method is used to separate daily SAT into a high frequency component, a MAC component, an interannual component, and a decadal-to-trend component. The results show that the EEMD method can reflect historical events reasonably well, indicating its adaptive and temporally local characteristics. It is shown that MAC is a temporally local reference frame and will not be altered over a particular time span by an exten-sion of data length, thereby making it easier for physical interpretation. In the MAC reference frame, the low frequency component is found more suitable for studying the interannual to longer timescale variability (ILV) than a 13-month window running mean, which does not exclude the annual cycle. It is also better than other traditional versions (annual or summer or winter mean) of ILV, which contains a portion of the annual cycle. The analysis reveals that the variability of the annual cycle could be as large as the magnitude of interannual variability. The possible physical causes of different timescale variability of SAT in China are further discussed. 展开更多
关键词 modulated annual cycle the Ensemble Empirical Mode Decomposition climate anomaly climate normal variability of surface air temperature in China
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A New Weighting Function for Estimating Microwave Sounding Unit Channel 4 Temperature Trends Simulated by CMIP5 Climate Models
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作者 张选泽 郑小谷 +1 位作者 杨赤 骆三 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第3期779-789,共11页
A new static microwave sounding unit (MSU) channel 4 weighting function is obtained from using Coupled Model Inter-comparison Project, Phase 5 (CMIP5) historical multimodel simulations as inputs into the fast Radi... A new static microwave sounding unit (MSU) channel 4 weighting function is obtained from using Coupled Model Inter-comparison Project, Phase 5 (CMIP5) historical multimodel simulations as inputs into the fast Radiative Transfer Model for TOVS (RTTOV v10). For the same CMIP5 model simulations, it is demonstrated that the computed MSU channel 4 brightness temperature (T4) trends in the lower stratosphere over both the globe and the tropics using the proposed weighting function are equivalent to those calculated by RTTOV, but show more cooling than those computed using the traditional UAH (University of Alabama at Huntsville) or RSS (Remote Sensing Systems in Santa Rosa, California) static weighting functions. The new static weighting function not only reduces the computational cost, but also reveals reasons why trends using a radiative transfer model are different from those using a traditional static weighting function. This study also shows that CMIP5 model simulated T4 trends using the traditional UAH or RSS static weighting functions show less cooling than satellite observations over the globe and the tropics. Although not completely removed, this difference can be reduced using the proposed weighting function to some extent, especially over the tropics. This work aims to explore the reasons for the trend differences and to see to what extent they are related to the inaccurate weighting functions. This would also help distinguish other sources for trend errors and thus better understand the climate change in the lower stratosphere. 展开更多
关键词 CMIP5 RTTOV MSU weighting function lower stratospheric temperature variability
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Conduction Properties of highly Conductive a-Si∶H∶Y Alloy Films at Low Temperature
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作者 张德恒 王家俭 +2 位作者 刘汝军 高汝伟 王矜奉 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第2期50-54,共5页
Conductive n type a Si∶H∶Y alloy films with the conductivity as high as 60 S/cm have been deposited on Si substrate by radio frequency sputtering. In the temperature range 20~300 K, for samples with large Y conte... Conductive n type a Si∶H∶Y alloy films with the conductivity as high as 60 S/cm have been deposited on Si substrate by radio frequency sputtering. In the temperature range 20~300 K, for samples with large Y contents, the thermally activated conduction is also observed and the plots of lg σ vs. 1/ T can be fitted by two linear functions with different slopes. The corresponding temperatures of the kinks between the two straight lines depend on the Y contents in the samples. For small Y content films, the conductivities can be fitted to the funciton σ∝ exp (-1/ T 1/4 ). The present results are interpreted using different conduction mechanisms in different temperature ranges for samples with different Y contents. 展开更多
关键词 Rare earths a Si∶H∶Y alloy CONDUCTIVITY variable temperature conduction
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Spatial and Temporal Patterns of In Situ Sea Surface Temperatures within the Gulf of Mexico from 1901-2010
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作者 Jason Allard John V. Clarke III Barry D. Keim 《American Journal of Climate Change》 2016年第3期314-343,共30页
This work examines the spatial and temporal patterns of seasonal sea surface temperatures (SSTs) across the Gulf of Mexico (GoM) for the period 1901-2010. The Extended Reconstructed Sea Surface Temperature, version 4 ... This work examines the spatial and temporal patterns of seasonal sea surface temperatures (SSTs) across the Gulf of Mexico (GoM) for the period 1901-2010. The Extended Reconstructed Sea Surface Temperature, version 4 (ERSST.v4), dataset was selected for this study over other reconstructions because of its 2° × 2° grid cell spatial resolution, its recent update to adjust for known biases in SST observations, and its ability to be compared to other in situ studies of GoM SSTs. The monthly ERSST.v4 data were averaged seasonally for each year and grid cell in the GoM. Seasonal SST trends were then calculated for each grid cell with varying start dates (e.g., 1901-2010, 1911- 2010) to account for nonlinear SST changes over the study period. Results indicate that the GoM SSTs closely resemble those of global annual temperature trends: SSTs warmed from 1901 to ~1940, followed by a period with little trend or a slight cooling until the mid-1970s, and then a warming afterwards through 2010. The spatial patterns and magnitudes of SST changes, however, varied by season and location within the GoM. The spatial patterns involved gradients with latitudinal and/or longitudinal components: a southwest-northeast (warmer-cooler) gradient in winter, an east-west (warmer-cooler) gradient in spring and fall, and a northwest-southeast (warmer-cooler) gradient in summer. The magnitude of SST changes tended to be largest in summer, followed by spring, fall, and winter. The long-term (1901-2010) SST trends were significant throughout the GoM in summer and fall, but only significant towards the southwestern GoM in winter and spring. These results have implications in discussion of climate change and its impacts on tropical activity in the GoM Basin. 展开更多
关键词 Sea Surface temperature Gulf of Mexico temperature Reconstructions temperature Variability
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Magnitude and direction of temperature variability affect hospitalization for myocardial infarction and stroke:population-based evidence from Guangzhou,China
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作者 Zhou Yang Murui Zheng +5 位作者 Ze-Lin Yan Hui Liu Xiangyi Liu Jie-Qi Jin Jiagang Wu Chun-Quan Ou 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2024年第3期1-11,共11页
Relationships between nonoptimal temperatures and cardiovascular disease(CVD)mortality have been well documented.However,evidence of the association between temperature variability(TV)and CVD morbidity is limited.This... Relationships between nonoptimal temperatures and cardiovascular disease(CVD)mortality have been well documented.However,evidence of the association between temperature variability(TV)and CVD morbidity is limited.This study aimed to quantify the risk and burden of CVD-related hospitalization associated with the magnitude and direction of TV.Data on meteorology and population-based hospitalizations for myocardial infarction(MI)and stroke were collected in Guangzhou,China,from 2013 to 2017.Hourly temperature variability(HTV)was measured as the standard deviation of hourly temperature records over specific exposure days.The direction(upward or downward)of HTV was defined as the average daily mean temperature change relative to that of the previous day during the exposure period.Quasi-Poisson regression was applied to assess the impact of HTV after adjusting for the daily mean temperature,and the hospitalization fractions attributable to HTV were calculated.A 1℃-increase in HTV was significantly associated with a 2.24%and 1.72%increase in hospitalizations for MI and hemorrhagic stroke(HS)at lag 0–1 d,respectively,and a 1.55%increase in hospitalizations for ischemic stroke(IS)at lag 0–3 d.During the study period,5.99%,4.64%,and 4.53%of MI,HS,and IS hospitalizations,respectively,were attributable to HTV.The upward TV exerts acute effects on CVD hospital admissions,whereas the impact of downward TV generally lags.These findings highlight the importance of the magnitude and direction of temperature fluctuations,in addition to the mean level,in assessing the adverse health impacts of temperature variations. 展开更多
关键词 Hourly temperature variability CARDIOVASCULAR HOSPITALIZATION Direction China
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Environmental Protection and Energy Color Changing Clothing Design under the Background of Sustainable Development 被引量:1
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作者 Jingyu Dai Hongyu Dai +1 位作者 Yutong Xie T.Indumathi 《Journal of Renewable Materials》 SCIE EI 2022年第11期2717-2728,共12页
In order to promote the application of clean energy technology in clothing and promote the integration of industrial development and artificial intelligence wearable technology,this study elaborates the energy applica... In order to promote the application of clean energy technology in clothing and promote the integration of industrial development and artificial intelligence wearable technology,this study elaborates the energy application characteristics of intelligent wearable products at home and abroad and its application in different fields,aiming at the current research status of wearable technology in the field of textile and clothing.The wearable distributed generation technology is classified,and a creative clothing design for detecting climate temperature is designed.Based on the monitoring of body temperature,the changes in clothing pattern color can reflect people’s health and emotional status.At the same time,it can also be applied to the screening of abnormal body temperature during the COVID-19. 展开更多
关键词 Clean energy temperature variable materials WEARABLE clothing design
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Temperature-variable high-frequency dynamic modeling of PIN diode
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作者 叶尚斌 张佳佳 +1 位作者 张逸成 姚勇涛 《Journal of Semiconductors》 EI CAS CSCD 2016年第4期82-87,共6页
The PIN diode model for high frequency dynamic transient characteristic simulation is important in conducted EMI analysis. The model should take junction temperature into consideration since equipment usually works at... The PIN diode model for high frequency dynamic transient characteristic simulation is important in conducted EMI analysis. The model should take junction temperature into consideration since equipment usually works at a wide range of temperature. In this paper, a temperature-variable high frequency dynamic model for the PIN diode is built, which is based on the Laplace-transform analytical model at constant temperature. The relationship between model parameters and temperature is expressed as temperature functions by analyzing the physical principle of these parameters. A fast recovery power diode MUR1560 is chosen as the test sample and its dynamic performance is tested under inductive load by a temperature chamber experiment, which is used for model parameter extraction and model verification. Results show that the model proposed in this paper is accurate for reverse recovery simulation with relatively small errors at the temperature range from 25 to 120 ℃. 展开更多
关键词 PIN diode Laplace transform temperature variable model parameter extraction
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Effect of Curing Regime on Degree of Al^(3+) Substituting for Si^(4+) in C-S-H Gels of Hardened Portland Cement Pastes 被引量:5
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作者 胡晨光 胡曙光 +2 位作者 DING Qingjun FENG Xiaoxin HUANG Xiulin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第3期546-552,共7页
The effect of curing regime on degree ofAl3+ substituting for Si^4+ (Al/Si ratio) in C-S-H gels of hardened Portland cement pastes was investigated by 29Si magic angel spinning (MAS) nuclear magnetic resonance ... The effect of curing regime on degree ofAl3+ substituting for Si^4+ (Al/Si ratio) in C-S-H gels of hardened Portland cement pastes was investigated by 29Si magic angel spinning (MAS) nuclear magnetic resonance (NMR) with deconvolution technique. The curing regimes included the constant temperature (20, 40, 60 and 80 ℃) and variable temperature (simulated internal temperature of mass concrete with 60 ℃ peak). The results indicate that constant temperature of 20 ℃ is beneficial to substitution ofAl3+ for Si4+, and AI/Si ratio changes to be steady after 180 d. The increase of Al/Si ratio at 40 ℃is less than that at 20℃ for 28 d. The other three regimes of high temperature increase Al/Si ratio only before 3 d, on the contrary to that from 3 to 28 d. However, the 20 ℃ curing stage from 28 to 180 d at variable temperature regime, is beneficial to the increase of AI/Si ratio which is still lower than that at constant temperature regime of 20 ℃ for the same age. A nonlinear relation exists between the Al/Si ratio and temperature variation or mean chain length (MCL) of C-S-H gels, furthermore, the amount ofAl3+ which can occupy the bridging tetrahedra sites in C-S-H structure is insufficient in hardened Portland cement pastes. 展开更多
关键词 constant temperature variable temperature degree of Al3+ substituting for Si4+ C-S-H hardened cement pastes
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Opposing Trends of Winter Cold Extremes over Eastern Eurasia and North America under Recent Arctic Warming 被引量:1
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作者 Shuangmei MA Congwen ZHU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第12期1417-1434,共18页
Under recent Arctic warming,boreal winters have witnessed severe cold surges over both Eurasia and North America,bringing about serious social and economic impacts.Here,we investigated the changes in daily surface air... Under recent Arctic warming,boreal winters have witnessed severe cold surges over both Eurasia and North America,bringing about serious social and economic impacts.Here,we investigated the changes in daily surface air temperature(SAT)variability during the rapid Arctic warming period of 1988/89–2015/16,and found the daily SAT variance,mainly contributed by the sub-seasonal component,shows an increasing and decreasing trend over eastern Eurasia and North America,respectively.Increasing cold extremes(defined as days with daily SAT anomalies below 1.5 standard deviations)dominated the increase of the daily SAT variability over eastern Eurasia,while decreasing cold extremes dominated the decrease of the daily SAT variability over North America.The circulation regime of cold extremes over eastern Eurasia(North America)is characterized by an enhanced high-pressure ridge over the Urals(Alaska)and surface Siberian(Canadian)high.The data analyses and model simulations show the recent strengthening of the high-pressure ridge over the Urals was associated with warming of the Barents–Kara seas in the Arctic region,while the high-pressure ridge over Alaska was influenced by the offset effect of Arctic warming over the East Siberian–Chukchi seas and the Pacific decadal oscillation(PDO)–like sea surface temperature(SST)anomalies over the North Pacific.The transition of the PDO-like SST anomalies from a positive to negative phase cancelled the impact of Arctic warming,reduced the occurrence of extreme cold days,and possibly resulted in the decreasing trend of daily SAT variability in North America.The multi-ensemble simulations of climate models confirmed the regional Arctic warming as the driver of the increasing SAT variance over eastern Eurasia and North America and the overwhelming effect of SST forcing on the decreasing SAT variance over North America.Therefore,the regional response of winter cold extremes at midlatitudes to the Arctic warming could be different due to the distinct impact of decadal SST anomalies. 展开更多
关键词 daily surface air temperature variability extreme cold days Arctic warming eastern Eurasia North America
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Effect of climate change on seasonal monsoon in Asia and its impact on the variability of monsoon rainfall in Southeast Asia 被引量:8
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作者 Yen Yi Loo Lawal Billa Ajit Singh 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第6期817-823,共7页
Global warming and climate change is one of the most extensively researched and discussed topical issues affecting the environment.Although there are enough historical evidence to support the theory that climate chang... Global warming and climate change is one of the most extensively researched and discussed topical issues affecting the environment.Although there are enough historical evidence to support the theory that climate change is a natural phenomenon,many research scientists are widely in agreement that the increase in temperature in the 20 th century is anthropologically related.The associated effects are the variability of rainfall and cyclonic patterns that are being observed globally.In Southeast Asia the link between global warming and the seasonal atmospheric flow during the monsoon seasons shows varying degree of fuzziness.This study investigates the impact of climate change on the seasonality of monsoon Asia and its effect on the variability of monsoon rainfall in Southeast Asia.The comparison of decadal variation of precipitation and temperature anomalies before the 1970 s found general increases which were mostly varying.But beyond the 1970 s,global precipitation anomalous showed increases that almost corresponded with increases in global temperature anomalies for the same period.There are frequent changes and a shift westward of the Indian summer monsoon.Although precipitation is observed to be 70%below normal levels,in some areas the topography affects the intensity of rainfall.These shifting phenomenon of other monsoon season in the region are impacting on the variability of rainfall and the onset of monsoons in Southeast Asia and is predicted to delay for 15 days the onset of the monsoon in the future.The variability of monsoon rainfall in the SEA region is observed to be decadal and the frequency and intensity of intermittent flooding of some areas during the monsoon season have serious consequences on the human,financial,infrastructure and food security of the region. 展开更多
关键词 Climate change temperature anomalies Precipitation anomalies Seasonal monsoons Rainfall variability Southeast Asia
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Interdecadal change of winter SST variability in the Kuroshio Extension region and its linkage with Aleutian atmospheric low pressure system 被引量:3
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作者 YU Peilong ZHANG Lifeng +1 位作者 ZHANG Yongchui DENG Bing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第5期24-37,共14页
By utilizing multiple datasets from various sources available for the last 100 years, the existence for the interdecadal change of the winter sea surface temperature(SST) variability in the Kuroshio Extension(KE) ... By utilizing multiple datasets from various sources available for the last 100 years, the existence for the interdecadal change of the winter sea surface temperature(SST) variability in the Kuroshio Extension(KE) region is investigated. And its linkage with the Aleutian Low(AL) activity changes is also discussed. The results find that the KE SST variability exhibits the significant ~6 a and ~10 a oscillations with obvious interdecadal change. The ~6 a oscillation is mainly detected during 1930–1950, which is largely impacted by the anomalous surface heat flux forcing and Ekman heat transport associated with the AL intensity variation. The ~10 a oscillation is most evident after the 1980s, which is predominantly triggered by the AL north-south shift through the bridge of oceanic Rossby waves. 展开更多
关键词 sea surface temperature(SST) variability interdecadal change Kuroshio Extension Aleutain Low
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Charge carrier dynamics in different crystal phases of CH_(3)NH_(3)PbI_(3)perovskite 被引量:2
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作者 Efthymis Serpetzoglou Ioannis Konidakis +6 位作者 George Kourmoulakis Ioanna Demeridou Konstantinos Chatzimanolis Christos Zervos George Kioseoglou Emmanuel Kymakis Emmanuel Stratakis 《Opto-Electronic Science》 2022年第4期1-10,22-27,共16页
Despite that organic-inorganic lead halide perovskites have attracted enormous scientific attention for energy conversion applications over the recent years,the influence of temperature and the type of the employed ho... Despite that organic-inorganic lead halide perovskites have attracted enormous scientific attention for energy conversion applications over the recent years,the influence of temperature and the type of the employed hole transport layer(HTL)on the charge carrier dynamics and recombination processes in perovskite photovoltaic devices is still largely unexplored.In particular,significant knowledge is missing on how these crucial parameters for radiative and non-radiative recombinations,as well as for efficient charge extraction vary among different perovskite crystalline phases that are induced by temperature variation.Herein,we perform micro photoluminescence(pPL)and ultrafast time resolved transient absorption spectroscopy(TAS)in Glass/Perovskite and two dierent Glass/ITO/HTL/Perovskite configurations at temperatures below room temperature,in order to probe the charge carrier dynamics of different perovskite crystalline phases,while considering also the effect of the employed HTL polymer.Namely,CH_(3)NH_(3)Pbb films were deposited on Glass,PEDOT:PSS and PTAA polymers,and the developed Glass/CH_(3)NH_(3)PbI_(3)and Glass/ITO/HTL/CH_(3)NH_(3)PbI_(3)architectures were studied from 85 K up to 215 K in order to explore the charge extraction dynamics of the CH_(3)NH_(3)PbI_(3)orthorhombic and tetragonal crystalline phases.It is observed an unusual blueshift of the bandgap with temperature and the dual emission at temperature below of 100 K and also,that the charge carrier dynamics,as expressed by hole injection times and free carrier recombination rates,are strongly depended on the actual pervoskite crystal phase,as well as,from the selected hole transport material. 展开更多
关键词 transient absorption spectroscopy p-photoluminescence variable temperature perovskite crystalline phases hole transport layer charge carrier dynamics
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Thermal boundary layer in stagnation-point flow past a permeable shrinking sheet with variable surface temperature 被引量:1
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作者 MdSharif Uddin Krishnendu Bhattacharyya 《Propulsion and Power Research》 SCIE 2017年第3期186-194,共9页
An investigation is made to study the heat transfer in boundary layer stagnationpoint flow over a non-isothermal permeable shrinking sheet with suction/injection.In this study,power-law variation of sheet temperature... An investigation is made to study the heat transfer in boundary layer stagnationpoint flow over a non-isothermal permeable shrinking sheet with suction/injection.In this study,power-law variation of sheet temperature is considered.By similarity transformation,the governing equations with the boundary conditions are transformed to self-similar nonlinear ordinary differential equations and then those are solved numerically by shooting method.In presence of variable sheet temperature,the variation of temperature is analysed.For larger shrinking rate compared to that of straining rate,dual solutions for velocity and temperature are obtained.It is found that for positive value of power-law exponent of variable sheet temperature heat transfer at the sheet as well as heat absorption at the sheet with temperature overshoot near the sheet occur and for negative value heat transfer from the sheet occurs though there is overshoot away from the sheet.With increasing positive power-law exponent heat transfer reduces for first solution and heat absorption enhances for second solution.Whereas,with increasing magnitude of negative power-law exponent heat transfer increases for second solution and for first solution the heat transfer increases for larger shrinking rate and it decreases for smaller shrinking rate.Due to suction heat transfer/absorption increases in all cases and for injection heat transfer/absorption increases for first solution and decreases for second solution.Also,interesting effects of suction/injection and Prandtl number on temperature distribution are observed when the sheet temperature varies(directly/inversely)along the sheet. 展开更多
关键词 Dual solutions Heat transfer Boundary layer Stagnation-point flow Non-isothermal permeable shrinking sheet Suction/injection variable surface temperature
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IAP/LASG全球海-陆-气耦合系统模式的纬向平均大气气候态分析(英文)
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作者 张韬 郭裕福 吴国雄 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第6期1091-1102,共12页
The results of four versions of IAP/LASG Global Ocean-Atmosphere-Land System Model (GOALS) are analyzed separately over the oceans and over continents, and compared with observed data. Some fundamental atmospheric var... The results of four versions of IAP/LASG Global Ocean-Atmosphere-Land System Model (GOALS) are analyzed separately over the oceans and over continents, and compared with observed data. Some fundamental atmospheric variables including surface air temperature (SAT), sea level pressure (SLP) and precipitation are examined to evaluate the ability of the GOALS model to simulate the contemporary climate and climate variability. In general, all four versions of the GOALS model are capable of reproducing the main features of the mean state and seasonal variation of the observed climate with reasonable accuracy. The evaluation also reveals some weakness of the model. According to this study, we can clearly see that the essential discrepancy of global averaged SLP lies over the continents in boreal summer. The simulated higher SAT over land versus the observed is mainly due to the effect of the land surface process. It is worth noting the underestimation by simulated precipitation rates mostly appears over the oceans, yet over-land precipitation is higher in high and middle latitudes than the observed for the boreal winter. Through intercomparisons among different versions of the model, it can be clearly seen that the incorporation of the diurnal cycle of solar radiation apparently improves the simulation of SAT, especially in the low and middle latitudes over land. Also, the introduction of the diurnal cycle shows a great improvement in precipitation in tropical continents and wintertime precipitation in high and middle latitudes. Furthermore, based on the daily flux anomaly exchange scheme (DFA), the latest version of GOALS model simulated over-ocean temperature variability is improved in the low and middle latitudes. Having compared the standard deviation of the annual mean surface air temperature (SAT) simulated by the GOALS model to observation, it is found that all four versions of the GOALS model underestimate surface air temperature variability over both oceans and land relative to observations. Several factors that may contribute to these differences between simulated and observed temperature variability are identified. 展开更多
关键词 zonal mean climate state temperature variability air-sea coupling
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The regime shift in the 1960s and associated atmospheric change over the southern Indian Ocean
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作者 WANG Tianyu DU Yan LIAO Xiaomei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第1期1-8,共8页
The change of sea surface temperature(SST) in the southern Indian Ocean(SIO) during the recent six decades has been analyzed based on oceanic reanalysis and model, as well as atmospheric data. The results show tha... The change of sea surface temperature(SST) in the southern Indian Ocean(SIO) during the recent six decades has been analyzed based on oceanic reanalysis and model, as well as atmospheric data. The results show that a thermal regime shift in SIO during the 1960 s, which is not caught enough attentions, has been of equal magnitude to the linear warming since 1970. Empirical Orthogonal Function(EOF) analyses reveal that a thermal shift is combined with atmospheric changes such as the weakening of westerly during the period of 1960–1967. Inner dynamic connections can be defined that when the westerly winds turn weak, the anticyclonic wind circulation between westerly winds and the trade winds decreases, which further reduces the SST to a negative peak in this period. It is noted that the shifts in the 1960 s are also evident for Southern Hemisphere. For example, subtropical high and the entire westerly winds belt at high latitudes both change dramatically in the 1960 s. This large-scaled process maybe link to the change of southern annular mode(SAM). 展开更多
关键词 sea surface temperature regime shift southern Indian Ocean interdecadal variabilities linear trend
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The characteristics of temperature variability with terrain, latitude and longitude in Sichuan- Chongqing Region 被引量:11
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作者 SHAO Jing'an LI Yangbing NI Jiupai 《Journal of Geographical Sciences》 SCIE CSCD 2012年第2期223-244,共22页
Using the daily temperature data of 95 meteorological stations from Sichuan-Chongqing Region and its surrounding areas, this paper adopted these methods (e.g., linear regression, trend coefficient, geographical stati... Using the daily temperature data of 95 meteorological stations from Sichuan-Chongqing Region and its surrounding areas, this paper adopted these methods (e.g., linear regression, trend coefficient, geographical statistics, gray relational analysis and spatial analysis functions of GIS) to analyze the relations of temperature variability with topography, latitude and longitude. Moreover, the rank of gray correlation between temperature variability and elevation, longitude, latitude, topographic position and surface roughness also was meas- ured. These results indicated: (1) The elevation affected temperature variability most obviously, followed by latitude, and longitude. The slope of the linear regression between temperature change rate and elevation, latitude and longitude was 0.4142, 0.0293 and -0.3270, respectively (2) The rank of gray correlation between temperature change rate and geographic factors was elevation 〉 latitude 〉 surface roughness 〉 topographic position 〉 longitude. The gray correla- tion degree between temperature change rate and elevation was 0.865, followed by latitude with 0.796, and longitude with 0.671. (3) The rate of temperature change enhanced with the increase of elevation. Especially, the warming trend was significant in the plateau and mountain areas of western Sichuan, and mountain and valley areas of southwestern Sichuan (with the warming rate of 0.74℃/10a during the 1990s). However, there was a weak warming trend in Sichuan Basin and its surrounding low mountain and hilly areas. (4) The effects of latitude on temperature change rate presented the specific regulation, which the warming rate of low-latitude areas was more significant than that of high-latitude areas. However, they were consistent with the regulation that the increasing of low temperature controlled most of the warming trend, due to the effects of terrain and sically, temperature variability along longitude elevation on annual mean temperature. (5) Ba- direction resulted from the regular change of elevation along longitude. It was suggested that, in Sichuan-Chongqing Region, special features of temperature variability largely depended on the terrain complexity (e.g., undulations, mutations and roughness). The elevation level controlled only high or low annual mean temperature and the range of temperature change rate in the macro sense. 展开更多
关键词 temperature variability geographic factors transect analysis grey relation short-term scale Sichuan- Chongqing Region
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Patterns of Multiscale Temperature Variability over the Eastern and Central Tibetan Plateau During 1960-2008 被引量:1
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作者 宋辞 裴韬 +1 位作者 周成虎 何亚文 《Acta meteorologica Sinica》 SCIE 2013年第4期521-540,共20页
Climate variability is an important inherent characteristic of climate and it varies on all timescales. Through examination of temperature variability on multiple temporal scales at 63 stations over the eastern and ce... Climate variability is an important inherent characteristic of climate and it varies on all timescales. Through examination of temperature variability on multiple temporal scales at 63 stations over the eastern and central Tibetan Plateau (TP) during 1960-2008, we find decreasing trends in daily and intraannual temperature, especially in cold seasons (autumn and winter). These changes are more sensitive than those in the eastern China coastal region at the same latitude and indicate an asymmetric change of temperature, with hourly, daily, and monthly trends in cold periods stronger than those in warm periods during the recent years. The variation of interannual temperature is complex, showing an increasing trend in autumn and winter and decreasing trend in spring and summer, which is similar to those in the northern polar region. The changes of multiscale variability of temperature are mainly related to changes of atmospheric water vapor, cloudiness, anthropogenic aerosols, monsoon-driven climate, and some local factors. To find the influences of local conditions on temperature variability, we analyze the effects of altitude, topography, and urbanization. The results show that elevation is strongly and positively related to diurnal temperature range (DTR) and slightly positively related to interannual temperature variability (IVT), but intraannual temperature variability shows no clear elevation dependency. Topography and urbanization also play important roles in multiscale temperature variability. Finally, strong relationships are observed between temperature variability on each scale and different extreme indices. 展开更多
关键词 multiscale temperature variability Tibetan Plateau altitude effect topography effect
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Understanding the thermal stability of human serum proteins with the related near-infrared spectral variables selected by Monte Carlo-uninformative variable elimination 被引量:2
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作者 Xiu-Wei Liu Xiao-Yu Cui +2 位作者 Xiao-Ming Yu Wen-Sheng Cai Xue-Guang Shao 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第7期1447-1452,共6页
Understanding the thermal stability of the proteins in human serum is essential since human serum is the important source of pharmaceutical proteins. Near-infrared(NIR) spectroscopy was applied to the investigation ... Understanding the thermal stability of the proteins in human serum is essential since human serum is the important source of pharmaceutical proteins. Near-infrared(NIR) spectroscopy was applied to the investigation of thermal changes in secondary structure and hydration of human serum proteins.However, as a multicomponent system, the overlap of the broad NIR bands makes the structural analysis very difficult directly using the spectra of serum samples. Therefore, continuous wavelet transform(CWT) was used to improve the resolution of NIR spectra, and Monte Carlo-uninformative variable elimination(MC-UVE) method was applied to the selection of the variables associated with the proteins for the structural analysis. The variables(5956, 5867, 5815, 5747, 4525, 4401, 4359 and 4328 cm^-1) related to protein secondary structures and those(7074, 6951, 6827 and 6700 cm 1) connected with water species were selected. Then, the thermal stability was analyzed through the intensity variations of the selected variables with temperature from 30℃ to 80 ℃. It was found that the variation of the spectral variables related to both a-helix and b-sheet changes apparently around 60 ℃, indicating the beginning of the thermal denaturation and the transition from a-helix to b-sheet. Moreover, an obvious change was found around 60℃for the content of the water specie S3, i.e., the water cluster containing three hydrogen bonds. The result demonstrates that MC-UVE can identify the protein-related NIR spectral variables, and the water species may be a marker for investigation of the structural change of proteins in biochemical systems. 展开更多
关键词 Near-infrared spectroscopy temperature dependent spectroscopy Monte Carlo-uninformative variable elimination Protein Human serum
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