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Subsoiling and Ridge Tillage Alleviate the High Temperature Stress in Spring Maize in the North China Plain 被引量:20
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作者 TAO Zhi-qiang SUI Peng +5 位作者 CHEN Yuan-quan LI Chao NIE Zi-jin YUAN Shu-fen SHI Jiang-tao GAO Wang-sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2179-2188,共10页
High temperature stress(HTS) on spring maize(Zea mays L.) during the filling stage is the key factor that limits the yield increase in the North China Plain(NCP).Subsoiling(SS) and ridge tillage(R) were intr... High temperature stress(HTS) on spring maize(Zea mays L.) during the filling stage is the key factor that limits the yield increase in the North China Plain(NCP).Subsoiling(SS) and ridge tillage(R) were introduced to enhance the ability of spring maize to resist HTS during the filling stage.The field experiments were conducted during the 2011 and 2012 maize growing seasons at Wuqiao County,Hebei Province,China.Compared with rotary tillage(RT),the net photosynthetic rate,stomatal conductance,transpiration rate,and chlorophyll relative content(SPAD) of maize leaves was increased by 40.0,42.6,12.8,and 29.7% under SS,and increased by 20.4,20.0,5.4,and 14.2% under R,repectively.However,the treatments reduce the intercellular CO 2 concentration under HTS.The SS and R treatments increased the relative water content(RWC) by 11.9 and 6.2%,and the water use efficiency(WUE) by 24.3 and 14.3%,respectively,compared with RT.The SS treatment increased the root length density and soil moisture in the 0-80 cm soil profile,whereas the R treatment increased the root length density and soil moisture in the 0-40 cm soil profile compared with the RT treatment.Compared with 2011,the number of days with temperatures 33°C was more 2 d and the mean day temperature was higher 0.9°C than that in 2012,whereas the plant yield decreased by 2.5,8.5 and 10.9%,the net photosynthetic rate reduced by 7.5,10.5 and 18.0%,the RWC reduced by 3.9,5.6 and 6.2%,and the WUE at leaf level reduced by 1.8,5.2 and 13.1% in the SS,R and RT treatments,respectively.Both the root length density and the soil moisture also decreased at different levels.The yield,photosynthetic rate,plant water status,root length density,and soil moisture under the SS and R treatments declined less than that under the RT treatment.The results indicated that SS and R can enhance the HTS resistance of spring maize during the filling stage,and led to higher yield by directly improving soil moisture and root growth and indirectly improving plant water status,photosynthesis and grain filling.The study can provide a theoretical basis for improving yield of maize by adjusting soil tillage in the NCP. 展开更多
关键词 high temperature stress spring maize filling stage SUBSOILING ridge tillage
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Surface decarburization characteristics and relation between decarburized types and heating temperature of spring steel 60Si2MnA 被引量:10
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作者 Chao-lei Zhang Le-yu Zhou Ya-zheng Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第8期720-724,共5页
The characteristics of complete and partial decarburizations in spring steel 60Si2MnA were systematically investigated, including the microstructure, the hardness gradient, and the formation mechanism. The relation be... The characteristics of complete and partial decarburizations in spring steel 60Si2MnA were systematically investigated, including the microstructure, the hardness gradient, and the formation mechanism. The relation between decarburized types and heating temperature of the steel was comprehensively discussed. It is found that heating temper- ature has an important influence on the decarburized types. With the rise of heating temperature, the decarburized types change from no decarburization to complete decarburization, complete and partial decarburizations, partial decarburiza- tion, and no decarburization. 展开更多
关键词 spring steel DECARBURIZATION temperature MICROSTRUCTURE HARDNESS
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Diversity on the Interannual Variations of Spring Monthly Precipitation in Southern China and the Associated Tropical Sea Surface Temperature Anomalies 被引量:3
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作者 郭如月 潘蔚娟 +2 位作者 柯敏玲 魏维 王子谦 《Journal of Tropical Meteorology》 SCIE 2023年第3期337-346,共10页
There is a continuous and relatively stable rainy period every spring in southern China(SC).This spring precipitation process is a unique weather and climate phenomenon in East Asia.Previously,the variation characteri... There is a continuous and relatively stable rainy period every spring in southern China(SC).This spring precipitation process is a unique weather and climate phenomenon in East Asia.Previously,the variation characteristics and associated mechanisms of this precipitation process have been mostly discussed from the perspective of seasonal mean.Based on the observed and reanalysis datasets from 1982 to 2021,this study investigates the diversity of the interannual variations of monthly precipitation in spring in SC,and focuses on the potential influence of the tropical sea surface temperature(SST)anomalies.The results show that the interannual variations of monthly precipitation in spring in SC have significant differences,and the correlations between each two months are very weak.All the interannual variations of precipitation in three months are related to a similar western North Pacific anomalous anticyclone(WNPAC),and the southwesterlies at the western flank of WNPAC bring abundant water vapor for the precipitation in SC.However,the WNPAC is influenced by tropical SST anomalies in different regions each month.The interannual variation of precipitation in March in SC is mainly influenced by the signal of El Nino-Southern Oscillation,and the associated SST anomalies in the equatorial central-eastern Pacific regulate the WNPAC through the Pacific-East Asia(PEA)teleconnection.In contrast,the WNPAC associated with the interannual variation of precipitation in April can be affected by the SST anomalies in the northwestern equatorial Pacific through a thermally induced Rossby wave response.The interannual variation of precipitation in May is regulated by the SST anomalies around the western Maritime Continent,which stimulates the development of low-level anomalous anticyclones over the South China Sea and east of the Philippine Sea by driving anomalous meridional vertical circulation. 展开更多
关键词 spring precipitation monthly diversity interannual variation southern China tropical sea surface temperature
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Effects of Lower Temperature in Spring on Tea Yield in Xuancheng Area
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作者 Wang Dalin Wang Jun 《Meteorological and Environmental Research》 CAS 2014年第2期48-49,54,共3页
Data of daily mean temperature, precipitation, sunshine hours and tea yield in Xuancheng area from 1979 to 2008 were used to analyze the relationship between lower temperature in spring and tea yield. The results show... Data of daily mean temperature, precipitation, sunshine hours and tea yield in Xuancheng area from 1979 to 2008 were used to analyze the relationship between lower temperature in spring and tea yield. The results showed during 1979 -2008, the per unit area yield of tea in Xu- ancheng area fluctuated greatly in various years. The relative meteorological yield of tea changed greatly during 1979 -2008, and the decrease in tea yield occurred frequently over the past 30 years. Over the past 30 years, the probability of lower temperature in spring was 56.7%, and the probability of serious and extremely serious lower temperature in spring was 43.4%. In each off year with decrease in tea yield, medium or above lower temperature in spring occurred, showing that the impact of lower temperature in spring on tea yield was very obvious. 展开更多
关键词 Lower temperature in spring Tea yield Xuancheng China
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Analysis on the Influence of Spring Low Temperature on the Agriculture and the Formation Reason in Liaoning Province in 2010
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作者 HAN Xiu-jun1, YU Xiao-li2, WANG Gui-chun3 1. Liaoning Meteorological Observatory, Shenyang 110016, China 2. Dalian Meteorological Bureau in Liaoning Province, Dalian 116001, China 3. Jinzhou Meteorological Bureau in Dalian City of Liaoning Province, Jinzhou 116100, China 《Meteorological and Environmental Research》 CAS 2011年第4期15-17,共3页
[Objective] The research aimed to study the influence of spring low temperature on the agriculture and the formation reason in Liaoning Province in 2010. [Method] Based on the synoptics analysis principle, by analyzin... [Objective] The research aimed to study the influence of spring low temperature on the agriculture and the formation reason in Liaoning Province in 2010. [Method] Based on the synoptics analysis principle, by analyzing the atmospheric circulation situation and satellite cloud map, the influence of spring low temperature on the agriculture and the formation reason of low temperature weather in Liaoning Province during April-May, 2010 were discussed. [Result] The high-altitude situation analysis showed that it was two-trough-two-ridge situation in the high latitude of Eurasia in April, 2010. Ural Mountains high-pressure ridge strengthened to move eastward. Lake Baikal cold air went down toward the southeast along the front of ridge and strengthened into the cold vortex. Liaoning was in the front of cold vortex. Affected by the cold vortex, the temperature in Liaoning area was low. In the first dekad of May, 2010, the activity of cold air was frequent. There were two times cold vortex influence, and the temperature was still low. In the later period of middle dekad of May, the warm ridge entered, and the temperature rose. The high-altitude trough and the low-level jet were the main system and the dynamic condition of precipitation generation respectively. The cold vortex was the main reason of spring continuous low temperature generation, and the secondary reason was the more precipitation. [Conclusion] The research provided the reference basis for the prevention and prediction of spring low temperature in Liaoning Province. 展开更多
关键词 spring low temperature Agricultural influence Formation reason analysis Liaoning Province China
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Variation Characteristics of Low Temperature and Rainy Weather in Guangxi during Spring Sowing Period of Recent 50 Years
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作者 LI Yan-lan HUANG Zhuo QIN Wei-jian 《Meteorological and Environmental Research》 CAS 2011年第8期56-59,73,共5页
[Objective] The research aimed to study the variation characteristics of low temperature and rainy weather in Guangxi during spring sowing period of recent 50 years.[Method] Based on the daily average temperature data... [Objective] The research aimed to study the variation characteristics of low temperature and rainy weather in Guangxi during spring sowing period of recent 50 years.[Method] Based on the daily average temperature data from 1961 to 2010 at 88 meteorological stations in Guangxi,yearly days and end date of low temperature and rainy weather during spring sowing period were carried out statistics.The variation characteristics of low temperature and rainy weather in Guangxi during spring sowing period of recent 50 years were analyzed by using linear tendency calculation,phased analysis,Morlet wavelet analysis and correlation analysis.Moreover,the influences of climate warming on days and end date of low temperature and rainy weather in spring sowing period were analyzed.[Result] The average days of low temperature and rainy weather in Guangxi during spring sowing period from 1961 to 2010 was during 3.5-23.2 d.The regional distribution characteristics were that it was more in northeast and mountain zone,and less in southwest and valley.The regional distribution characteristics of end date were that it was late in northeast and mountain zone,and early in southwest and valley.The days of low temperature and rainy weather in Guangxi during spring sowing period of recent 50 years presented slight decrease trend,and the end date presented slight advancing trend.The phased variation characteristics of days and end date of low temperature and rainy weather were obvious.The days of low temperature and rainy weather from the early 1980s to metaphase of 1990s was obviously more,and the end date was obviously later.After the 1990s,the days of low temperature and rainy weather was obviously less,and the end date was obviously earlier.The days of low temperature and rainy weather had periodic oscillation signals of 4,6,8,10-14 years.The end date had periodic oscillation signals of 6,12-14 years.The days and end date of low temperature and rainy weather in Guangxi during spring sowing period significantly related to average temperature from middle dekad of February to first dekad of April.The climate warming made that the days of low temperature and rainy weather tended to decrease,and the end date tended to advance.[Conclusion] The research provided reference for further understanding the occurrence rule of low temperature and rainy weather,going after profits and avoiding disadvantages,reasonably arranging production,carrying out correlated research. 展开更多
关键词 spring sowing period Low temperature and rainy weather Variation characteristics GUANGXI China
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Effects of Temperature and Humidity Changes inside and outside Insect-proof Net in the Spring on the Spring Shoot Growth of Citrus Shatangju
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作者 Xiaofeng ZHANG Yanjun GUO +4 位作者 Hui JIANG Liying GUO Xiqin ZHOU Yaping HU Qianhua JI 《Asian Agricultural Research》 2018年第1期69-72,共4页
The experiment was mainly used to study the effect of insect-proof net mulching cultivation technology on the temperature and humidity of the greenhouse and the spring shoot growth of citrus Shatangju. The results sho... The experiment was mainly used to study the effect of insect-proof net mulching cultivation technology on the temperature and humidity of the greenhouse and the spring shoot growth of citrus Shatangju. The results showed that the 40-mesh translucent insect-proof net had a positive effect on the spring shoot growth of Shatangju in the spring from January to April. In the meantime,according to the change of the temperature and humidity inside and outside the insect-proof net and the change of quantity of Aleyrodidae,Tetranychidae and Phyllocnisidae,it was found that the role of insect-proof net in enhancing the spring shoot growth of Shatangju was possibly achieved by the regulation of citrus pests and the temperature and humidity inside the net. 展开更多
关键词 Insect-proof net Citrus Shatangju spring shoot temperature and humidity Citrus pests
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Fault-weakening effect of reservoir temperature of hot spring and its influence on seismic activities
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作者 林元武 《Acta Seismologica Sinica(English Edition)》 CSCD 1994年第2期321-330,共10页
In this paper, the reservoir temperatures of 14 hot spring samples collected from the northern segment of theRed River Fault are calculated by using the mixing-model of SiO2-geothermometer. Based on the features ofres... In this paper, the reservoir temperatures of 14 hot spring samples collected from the northern segment of theRed River Fault are calculated by using the mixing-model of SiO2-geothermometer. Based on the features ofreservoir temperatures and densities of hot springs, the northern segment of the Red River Fault is furtherdivided into 4 sub-segments. The influence of weakening effect of water on seismic activities is discussed fromthe view point of fault-weakening effect of water. It is suggested that the difference in seismic activity between various sub-segments is principally caused by the difference in intensity of the fault-weakening effect ofwater of these sub-segments. The Eryuan sub-segment where the reservoir temperatures are high and the hotsprings are dense corresponds to a slipped region, however, the Jianchuan and Midu sub-segments where thereservoir temperatures are lower and the hot springs are fewer as well as the Dan sub-segment where the hotspring are very few all correspond to locked regions. It is suggested that Dan sub-segment is the riskiest region for strong earthquake preparation, while the possibility for strong earthquake preparation is very little inthe Eryuan sub-segment. 展开更多
关键词 northern segment of the Red River Fault SiO_2-geothermometer reservoir temperature of hot spring weakening effect seismicity potential earthquake source region
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Mild spring temperature rising affects the anti-oxidation and immune functions of Asian Short-toed Larks
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作者 Na Zhu Tingting Liu +2 位作者 Fei Wang Wei Liang Shuping Zhang 《Avian Research》 CSCD 2020年第2期115-121,共7页
Background:Predicting the possibility of severe effects of global warming on animals is important for understanding the ecological consequences of climate change on ecosystem.Spring is the season during which birds ha... Background:Predicting the possibility of severe effects of global warming on animals is important for understanding the ecological consequences of climate change on ecosystem.Spring is the season during which birds have to physiologically prepare for the subsequent breeding period,and unusual spring temperature rising probably becomes a heat stress to the birds which have adapted to the low spring temperature.Therefore,it is necessary to understand the physiological effect of spring warming on the temperate birds.Methods:Using the activities of blood anti-oxidative enzymes(SOD,CAT,GPx)and the concentrations of serum immunogloblins(IgA,IgY,IgM)as indicators,we compared the anti-oxidative and immune functions of Asian Shorttoed Larks(Calandrella cheleensis)captured between 10 and 15 March,2015 and housed under conditions of 21°C and 16°C.Results:The SOD activities of birds in 21°C group were significantly lower than those in 16°C group on all the treatment days.The CAT activities of the birds in 21°C group were significantly lower than those in 16°C group on the 1 st,5 th,13 th,17 treatment days.The GPx activities of the birds in 21°C group were signifthicantly lower than those in 16°C group on the 1 st,13 th and 17 th,but significantly higher on the 21 st treatment day.The IgA,IgY and IgM concentrations of birds in 21°C group were significantly lower than those in 16°C group on all the treatment days.Conclusions:This study shows that spring temperature rising negatively influences antioxibative and humoral immune functions,which indicates that spring climate warming might reduce the fitness of the temperate passerine birds which have adapted to the low spring temperature. 展开更多
关键词 Mild temperature rising Anti-oxidant capacity Immunity Asian Short-toed Larks spring
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The Relationship Between Temperature & Sunshine and Spring-Sown Wheat Quality
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作者 CAOGuang-cai WUDong-bing +7 位作者 SUNQun QIANGXiao-lin CHENHe-qin DONGMei KOUHao WANGJian-lin HOULi-bai LIMeng 《Agricultural Sciences in China》 CAS CSCD 2003年第12期1329-1337,共9页
In order to study the relationship between temperature & sunshine and spring-sown wheat qua lity, a spring-sown experiment with 3 wheat varieties was conducted in Rikaze, Lasa, Linzhi, Beijing and Shenyang from 1... In order to study the relationship between temperature & sunshine and spring-sown wheat qua lity, a spring-sown experiment with 3 wheat varieties was conducted in Rikaze, Lasa, Linzhi, Beijing and Shenyang from 1998 to 2001. The results indicated that significant difference on some quality characteristics of experimental wheat varieties were observed from different locations and different years. The results also showed: protein content was positively correlated with wet gluten content, falling number, the average day temperature and sunshine hours from heading to maturation; and negatively correlated with the growing days and the average diurnal temperature difference from sowing to maturation; wet gluten content was positively correlated with the average day temperature and sunshine hours during the same period. Sedimentation value and falling number were positively correlated with the average sunshine hours from sowing to maturation. The basic way of wheat production in Tibet was as follows: mainly developing medium gluten wheat varieties, suitably planting weak gluten wheat varieties, introducing some inland excellent varieties. 展开更多
关键词 temperature SUNSHINE spring-sown wheat Quality CORRELATION
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Mass-Spring-Damper Model with Steady State Parameters for Predicting the Movement of Liquid Column and Temperature Oscillation in Loop Heat Pipe
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作者 Ge Zhang Di Chen +1 位作者 Yingying Hong Li Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第5期82-89,共8页
In order to investigate the mechanism of the temperature oscillation in loop heat pipes,this paper investigated the movement of the phase interface as the changed input power by a mass-spring-damper model.The model wa... In order to investigate the mechanism of the temperature oscillation in loop heat pipes,this paper investigated the movement of the phase interface as the changed input power by a mass-spring-damper model.The model was solved with MATLAB and was used to explain the high-frequency and low-amplitude temperature oscillation.Temperature variation with the input power from 20 W to 75 W was investigated based on a LHP prototype in a literature.The model agreed well with the experimental data in the literature.The simulation results suggested that the movement of the liquid column was caused by the fluctuation of pressure difference applied on the liquid column and the stiffness coefficients of the vapor springs increasing with the input power.According to parameter analyses,the temperature oscillation at the outlet of the condenser can be weakened by increasing the mass of the liquid column and keeping the temperature at the outlet of the condenser steady. 展开更多
关键词 loop heat pipe temperature oscillation DISPLACEMENT mass-spring-da^nper model steady state para^neters
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Seasonal air temperature variations retrieved from a Geladaindong ice core, Tibetan Plateau
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作者 ZHANG Yongjun KANG Shichang +4 位作者 QIN Dahe REN Jiawen ZHANG Yulan Bjorn GRIGHOLM Paul MAYEWSKI 《Journal of Geographical Sciences》 SCIE CSCD 2007年第4期431-441,共11页
A 70-year history of precipitation δ^18O record has been retrieved using an ice core drilled from a plat portion of the firn area in the Guoqu Glacier (33°34'37.8″ N, 91°10'35.3″ E, 5720 m a.s.l.) on ... A 70-year history of precipitation δ^18O record has been retrieved using an ice core drilled from a plat portion of the firn area in the Guoqu Glacier (33°34'37.8″ N, 91°10'35.3″ E, 5720 m a.s.l.) on Mt. Geladaindong (the source region of Yangtze River) during October and November, 2005. Based on the seasonality of δ^18O records and the significant positive relationships between monsoon/non-monsoon δ^18O values and summer/spring air temperature from the nearby meteorological stations, the history of summer and spring air temperature have been reconstructed for the last 70 years. The results show that both summer and spring air temperature variations present similar trends during the last 70 years. Regression analysis indicates that the slope of the temperature-δ^18O relationship is 1.3℃/‰ for non-monsoon δ^18O values and spring air temperature, and 0.4℃/‰ for monsoon δ^18O values and summer air temperature. Variation of air temperature recorded in the ice core is consistent with that in the Northern Hemisphere (NH), however, the warming trend in the Geladaindong region is more intense than that in the NH, reflecting a higher sensitivity to global warming in the high elevation regions. In addition, warming trend is greater in spring than in summer. 展开更多
关键词 ice core δ^18O SUMMER spring air temperature variations Mt. Geladaindong Tibetan Plateau
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Estimation of reservoir temperature using silica and cationic solutes geothermometers:a case study in the Tengchong geothermal area
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作者 Xiaobo Zhang Qinghai Guo +3 位作者 Jiexiang Li Mingliang Liu Yanxin Wang Yijun Yang 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2015年第2期233-240,共8页
Reservoir temperature estimation is vitally important for assessing the exploitation potential of a geothermal field.In this study,the concentrations of major chemical constituents in geothermal water sampled from boi... Reservoir temperature estimation is vitally important for assessing the exploitation potential of a geothermal field.In this study,the concentrations of major chemical constituents in geothermal water sampled from boiling and hot springs in the Tengchong hydrothermal area were measured,and quartz and cationic solutes geothermometers were used to calculate subsurface temperatures.Log(Q/K) diagrams and Na-K-Mg triangular diagrams were applied to evaluating the equilibrium status of geothermal water samples with regard to reservoir minerals,and results were used to select suitable geothermometers.The results show that samples RH01,RH03,RH04,RH05,and LL16 were in or very close to full equilibrium with the selected minerals,and therefore a NaK geothermometer is appropriate.A K/Mg geothermometer,however,is applicable to LP08 and PZH18 whose chemical compositions adjusted to the shallow reservoir temperatures during their re-equilibrium processes.In contrast,cationic solute geothermometers are unsuitable for SQ20 and RH07,which are categorized as immature water in the Na-K-Mg diagram;a quartz geothermometer was adopted to evaluate the corresponding subsurface temperatures of these samples.According to the reservoir temperature estimation made in this study,there is at least one high-temperature reservoir below Rehai with a possible temperature range of 210-270 ℃. 展开更多
关键词 温度采样 地热区 阳离子 地温 溶质 腾冲 储层 地质温度计
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基于Spring Boot框架结构的环境试验设备远程温湿度校准系统 被引量:4
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作者 熊智淳 陈旭 +2 位作者 周伟 肖天雷 凌彦萃 《上海计量测试》 2020年第5期28-31,共4页
环境试验设备远程温湿度校准系统采用Spring Boot框架结构,将信号接收节点收到的温湿度数据通过主机存入数据库,用户通过系统访问数据库,浏览、分析处理数据。系统人机交互界面采用Web网页形式。可兼容计算机和手机的主浏览器,通过Web... 环境试验设备远程温湿度校准系统采用Spring Boot框架结构,将信号接收节点收到的温湿度数据通过主机存入数据库,用户通过系统访问数据库,浏览、分析处理数据。系统人机交互界面采用Web网页形式。可兼容计算机和手机的主浏览器,通过Web界面直接登录访问,不占本地内存。可同时监控检测校准20台以上设备,大大提高检测效率,满足昼夜检测的需求。可对测得数据进行分析,将检测业务、检测仪器、检测标准、检测客户等资源进行整合,提供一站式计量检测服务平台。 展开更多
关键词 环境试验设备 温湿度 远程测试 spring Boot框架 数据分析
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INTERANNUAL VARIABILITY OF WINTER AND SPRING PRECIPITATION IN SOUTH CHINA AND ITS RELATION TO MOISTURE TRANSPORT 被引量:8
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作者 吴蔚 温之平 +1 位作者 陈运光 崔少萍 《Journal of Tropical Meteorology》 SCIE 2013年第4期322-330,共9页
The interannual variability of winter and spring precipitation in South China(SC)and its relation to moisture transport are investigated by using the monthly precipitation data of NMIC,NCEP reanalysis datasets and NOA... The interannual variability of winter and spring precipitation in South China(SC)and its relation to moisture transport are investigated by using the monthly precipitation data of NMIC,NCEP reanalysis datasets and NOAA ERSST analysis datasets from 1960 to 2008.The results show that winter and spring precipitation in SC is less than normal from the 1960s to the start of the 1970s and from the end of the 1990s to the present.Most of rainfall anomalies on the whole regional scale of SC is well in phase during winter and spring,and the frequency of persistent drought is higher than that of persistent flood.Seasonal variations of moisture transport differences of SC between persistent drought and flood events are observed:the differences in winter are characterized by moisture transport from Bay of Bangle(BOB)and South China Sea(SCS),while differences in spring are characterized by that from SCS and North China(NC).There are two types of Ni o3.4 sea surface temperature anomaly(SSTA)related to persistent winter and spring drought(flood)events in SC,which are positive SSTA next to Ni o4(Ni o3)and negative SSTA next to Ni o3(Ni o4).Moreover,the variations of moisture transport from BOB and SC have important effects on persistent drought/flood in SC when the Ni o3.4 index is in the positive phase,while those from western North Pacific(WNP)-SC in winter and those from Philippine Sea(PHS)-SC and NC in spring primarily contribute to persistent drought/flood events in SC when the Ni o3.4 index is in the negative phase,and these stronger(weaker)moisture transports are observed in persistent flood(drought)during winter and spring regardless of the Ni o3.4 index.In conclusion,with the correlation between variations and distributions of Ni o3.4 SSTA and persistent drought/flood events in SC,moisture transport is responsible for the formation of precipitation anomalies.In addition,the moisture transport from SCS is most significantly correlated with persistent drought/flood events during winter and spring. 展开更多
关键词 INTERANNUAL variability EEOF analysis WINTER and spring PRECIPITATION moisture transport sea surface temperature ANOMALY
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Changing Spring Phenology Dates in the Three-Rivers Headwater Region of the Tibetan Plateau during 1960–2013 被引量:5
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作者 Shuang YU Jiangjiang XIA +1 位作者 Zhongwei YAN Kun YANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第1期116-126,共11页
The variation of the vegetation growing season in the Three-Rivers Headwater Region of the Tibetan Plateau has recently become a controversial topic. One issue is that the estimated local trend in the start of the veg... The variation of the vegetation growing season in the Three-Rivers Headwater Region of the Tibetan Plateau has recently become a controversial topic. One issue is that the estimated local trend in the start of the vegetation growing season(SOS)based on remote sensing data is easily affected by outliers because this data series is short. In this study, we determine that the spring minimum temperature is the most influential factor for SOS. The significant negative linear relationship between the two variables in the region is evaluated using Moderate Resolution Imaging Spectroradiometer–Normalized Difference Vegetation Index data for 2000–13. We then reconstruct the SOS time series based on the temperature data for 1960–2013.The regional mean SOS shows an advancing trend of 1.42 d(10 yr)during 1960–2013, with the SOS occurring on the 160th and 151st days in 1960 and 2013, respectively. The advancing trend enhances to 6.04 d(10 yr)during the past 14 years. The spatiotemporal variations of the reconstructed SOS data are similar to those deduced from remote sensing data during the past 14 years. The latter exhibit an even larger regional mean trend of SOS [7.98 d(10 yr)] during 2000–13. The Arctic Oscillation is found to have significantly influenced the changing SOS, especially for the eastern part of the region,during 2000–13. 展开更多
关键词 start of growing season normalized difference vegetation index spring minimum temperature Three-Rivers Headwater Region Arctic Oscillation
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Wavelet analysis of spring climate characteristics in arid aeolian area of agro-pastoral ecotone in China 被引量:2
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作者 Chun-xia ZOU Xiang-dong SHEN +2 位作者 Hong-yun LI Xia-zi LI Zhang-jun LI 《Water Science and Engineering》 EI CAS 2012年第3期269-277,共9页
The unique regional climate characteristics are among the main reasons for the frequent wind-sand activity in arid and cold areas in the agro-pastoral ecotone in Inner Mongolia, China. This paper focuses on the time s... The unique regional climate characteristics are among the main reasons for the frequent wind-sand activity in arid and cold areas in the agro-pastoral ecotone in Inner Mongolia, China. This paper focuses on the time series of temperature and precipitation in spring when sandstorms often occur in the area. Based on meteorological data for a 46-year period from 1959 to 2004, multi-scale variations and abrupt changes in temperature and precipitation were analyzed with the Mexican hat function (MHF) wavelet method, showing the multi-scale variation characteristics of temperature and precipitation, as well as the periods and change points at different time scales. The relationship between temperature and precipitation was obtained using the wavelet analysis method. Obvious staggered features of the variations of spring temperature and precipitation were observed in this agro-pastoral ecotone. The strongest oscillation periods of spring temperature variations were 1 and 22 years, while for precipitation, the strongest oscillation periods of variations were 2, 8, and 22 years. In addition, lower spring temperature corresponded to lower precipitation, whereas higher temperature yielded higher precipitation rate. 展开更多
关键词 spring temperature spring precipitation climate characteristics MHF waveletmethod arid aeolian area agro-pastoral ecotone
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Extreme spring cold spells in North China during 1961–2014 and the evolving processes 被引量:3
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作者 Ya-Li ZHU Hui-Jun WANG +1 位作者 Tao WANG Dong GUO 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第5期432-437,共6页
This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving processes.During an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies... This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving processes.During an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies and an anomalous anticyclone that continuously transport northern cold air to North China,causing significant,persistent,lower-than-normal daily temperatures.In fact,these positive SLP and anticyclonic wind anomalies begin to appear over northwestern Europe about 10 days prior to the ESCS.The anticyclonic wind anomalies keep moving southeastward and expand to the west of Lake Baikal until two days before the ESCS.Then,the center of the anomalous low-level anticyclone moves over Lake Baikal,inducing northerly wind anomalies that transport cold air into North China.In the following days,as the positive SLP anomalies weaken,the anomalous anticyclone and related northerly winds appear to wane,and the ESCS gradually comes to an end.The results may prove meaningful for the prediction and early warning of ESCSs. 展开更多
关键词 spring cold spell North China spring temperature extreme weather
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Changes in Mixed Layer Depth and Spring Bloom in the Kuroshio Extension under Global Warming 被引量:1
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作者 Ruosi ZHANG Shang-Ping XIE +1 位作者 Lixiao XU Qinyu LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第4期452-461,共10页
The mixed layer is deep in January-April in the Kuroshio Extension region. This paper investigates the response in this region of mixed layer depth (MLD) and the spring bloom initiation to global warming using the o... The mixed layer is deep in January-April in the Kuroshio Extension region. This paper investigates the response in this region of mixed layer depth (MLD) and the spring bloom initiation to global warming using the output of 15 models from CMIP5. The models indicate that in the late 21st century the mixed layer will shoal and the MLD reduction will be most pronounced in spring at about 33~N on the southern edge of the present deep-MLD region. The advection of temperature change in the upper 100 m by the mean eastward flow explains the spatial pattern of MLD shoaling in the models. Associated with the shoaling mixed layer, the onset of spring bloom inception is projected to advance due to the strengthened stratification in the warming climate. 展开更多
关键词 mixed layer depth global warming temperature advection spring bloom
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高温环境下弹簧功能-传感共形位移测量装置及方法
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作者 宁克焱 曾强 +4 位作者 田金山 赵攀 兰海 何家富 万丽 《兵工学报》 EI CAS CSCD 北大核心 2024年第2期662-670,共9页
机械装备的位移测量是状态检测和运动控制的关键,基于激光、电涡流、电感和电阻等原理的常规位移测量方法无法应对高端装备紧凑测试空间和高温、油污等恶劣环境条件下的位移测量挑战。基于材料力学与弹簧结构,构建一种新的弹簧功能-传... 机械装备的位移测量是状态检测和运动控制的关键,基于激光、电涡流、电感和电阻等原理的常规位移测量方法无法应对高端装备紧凑测试空间和高温、油污等恶劣环境条件下的位移测量挑战。基于材料力学与弹簧结构,构建一种新的弹簧功能-传感共形的位移测量模型,对弹簧整体受力及位移进行分析,确定位移-应变映射关系;基于有限元方法建立弹簧的应变-位移模型,分析弹簧位移测量的敏感点、不同组桥形式、位移激励频率等因素影响;通过搭建电液伺服高频冲击试验台,在扫频和加热工况下进行弹簧位移测量装置及方法的有效性和动态性能测试。试验结果表明:加载频率在100 Hz及以下时测试精度可达0.06 mm,高温适应性不低于275℃;经车用干片式制动器高温制动试验应用验证,在工作温度160℃以上仍能实时稳定获取机构的动态位移信号,为高温制动器状态检测及其故障诊断提供了嵌入式测试技术支撑;该共形位移测量方法在高温条件下具有良好的线性度和精度,为紧凑空间及高温等恶劣环境下位移测量提供了一种有效方法,尤其是在具有弹簧等弹性元件的情况下能够实现对原系统无影响的嵌入式测试。 展开更多
关键词 弹簧 位移测量 应变 高温 制动
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