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Spatial pattern recognition for near-surface high temperature increases in mountain areas using MODIS and SRTM DEM
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作者 WANG Yanxia YANG Lisha +1 位作者 HUANG Xiaoyuan ZHOU Ruliang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2025-2042,共18页
Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are n... Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are necessary but highly difficult due to the complicated environmental conditions and instrumental issues.This paper develops a spatial pattern recognition method to measure the near-surface high temperature increase(NSHTI),one of the lesser-attended changes.First,raster window measurement was proposed to calculate the temperature lapse rate using MODIS land surface temperature and SRTM DEM data.It fully considers the terrain heights of two neighboring cells on opposite or adjacent slopes with a moving window of 3×3 cell size.Second,a threshold selection was performed to identify the NSHTI cells using a threshold of-0.65℃/100 m.Then,the NSHTI strips were parameterized through raster vectorization and spatial analysis.Taking Yunnan,a mountainous province in southwestern China,as the study area,the results indicate that the NSHTI cells concentrate in a strip-like pattern along the mountains and valleys,and the strips are almost parallel to the altitude contours with a slight northward uplift.Also,they are located mostly at a 3/5 height of high mountains or within 400 m from the valley floors,where the controlling topographic index is the altitude of the terrain trend surface but not the absolute elevation and the topographic uplift height and cutting depth.Additionally,the NSHTI intensity varies with the geographic locations and the proportions increase with an exponential trend,and the horizontal width has a mean of about 1000 m and a maximum of over 5000 m.The result demonstrates that the proposed method can effectively recognize NSHTI boundaries over mountains,providing support for the modeling of weather and climate systems and the development of mountain resources. 展开更多
关键词 High temperature increase Mountain areas MODIS Spatial pattern recognition Raster window measurement Threshold selection
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Dielectric properties and temperature increase characteristics of zinc oxide dust from fuming furnace 被引量:1
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作者 张利波 马爱元 +4 位作者 刘晨辉 曲雯雯 彭金辉 罗永光 左勇刚 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期4004-4011,共8页
Cavity perturbation method was used to determine the dielectric properties (ε′,ε″, and tanδ) of zinc oxide dust in different apparent densities. The process was conducted to study the microwave-absorption prope... Cavity perturbation method was used to determine the dielectric properties (ε′,ε″, and tanδ) of zinc oxide dust in different apparent densities. The process was conducted to study the microwave-absorption properties of zinc oxide dust and the feasibility of microwave roasting zinc oxide dust to remove fluorine and chlorine. The dielectric constant, dielectric loss, and loss tangent were proportional to the apparent density of zinc oxide dust. The effects of sample mass and microwave power on the temperature increase characteristics under the microwave field were also studied. The results show that the apparent heating rate of the zinc oxide dust increases with the increase in microwave roasting power and decreases with the increase in the sample mass. The temperature of the samples reaches approximately 800 &#176;C after microwave treatment for 8 min, which indicates that the zinc oxide dust has strong microwave-absorption ability. 展开更多
关键词 zinc oxide dust apparent density dielectric properties microwave heating temperature increase characteristics
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Spatial distribution modeling of temperature increase for the uplifted mountain terrains and its characteristics in Southwest China 被引量:2
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作者 WANG Yan-xia DING Kun +1 位作者 LI Mao-biao ZHOU Ru-liang 《Journal of Mountain Science》 SCIE CSCD 2017年第11期2270-2283,共14页
Local temperature changes in mountain areas are significantly affected by the uplifted mountain terrains. Understanding how temperature increase with mountain terrains is an important component in accurately modeling ... Local temperature changes in mountain areas are significantly affected by the uplifted mountain terrains. Understanding how temperature increase with mountain terrains is an important component in accurately modeling the spatial distribution of temperature. The study, after minimizing the effect of elevation and latitude, quantitatively simulated the temperature increase in the uplifted mountain terrains, described the characteristics in the spatial distribution of warming areas with different magnitudes, and identified the correlated indices of mountain bodies for warming. Selecting Yunnan Province in southwest China as the study area, we simulated the warming field on a baseline surface at the average elevation of 2000 m and average latitude of 24.96°. The results indicated that the warming magnitudes in different local areas varied with the change in the spatial locations, and the warming process concentrated in the mountainous regions. Throughout the entire study area, the warming field presented a general pattern of three terraces from the regions of high mountains to middle mountains and then low mountains. The areasof high warming magnitude mainly surrounded large mountain bodies and were distributed on the upper part. The areas of low warming magnitude clustered in the valleys and basins of the middle mountain region, mostly on the lower part of the large mountain bodies and its branches. The areas with zero warming magnitude occurred in the low mountains and broad valleys, which were distributed largely on the lower parts of the middle mountains and in most of the valleys. Quantified sampling analysis demonstrated good positive correlation between the warming magnitudes in uplifted mountain terrains and the volume index of the mountain body, as well as elevation difference, with the coefficients corresponding to 0.82 and 0.91, respectively. 展开更多
关键词 Uplifted MOUNTAIN terrains temperature increase BASELINE surface Highwarming MAGNITUDE Remote sensing retrieval
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The effect of sea surface temperature increase on the potential habitat of Ommastrephes bartramii in the Northwest Pacific Ocean 被引量:10
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作者 XU Jie CHEN Xinjun +2 位作者 CHEN Yong DING Qi TIAN Siquan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第2期109-116,共8页
In the Northwest Pacific Ocean, the squid jigging fisheries from China, Japan and other countries and regions have targeted the west winter-spring cohort of neon flying squid(Ommastrephes bartramii) from August to N... In the Northwest Pacific Ocean, the squid jigging fisheries from China, Japan and other countries and regions have targeted the west winter-spring cohort of neon flying squid(Ommastrephes bartramii) from August to November since the 1970 s. This squid is a short-lived ecological opportunist with a life-span of about one year,and its population is labile and recruitment variability is driven by the environment or climate change. This variability provides a challenge for ones to forecast the key habitats affected by climate change. The catch data of O. bartramii from Chinese squid jigging fishery and the satellite-derived sea surface temperature(SST) data are used in the Northwest Pacific Ocean from August to November of 1998 to 2004, the SST preferences of O.bartramii corresponding to high values of catch per fishing day(CPUE) are determined and monthly potential habitats are predicted using a histogram analysis of the SST data. The possible changes in the potential habitats of O. bartramii in the Northwest Pacific Ocean are estimated under four climate change scenarios based on the Fourth Assessment Report(AR4) of the Intergovernmental Panel on Climate Change, i.e., 0.5, 1, 2 and 4°C increases in the SST because of the climate change. The results reveal an obvious poleward shift of the potential habitats of O. bartramii in the Northwest Pacific Ocean. 展开更多
关键词 Ommastrephes bartramii sea surface temperature increase potential habitat Northwest Pacific Ocean
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ESTIMATION OF THE CRITICAL RATE OF TEMPERATURE INCREASE OF THERMAL EXPLOSION OF NITROCELLULOSE USING NON-ISOTHERMAL DSC 被引量:1
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作者 胡荣祖 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第3期285-290,共6页
A method of estimating the critical rate of temperature increase of thermal explosion for the first orderautocatalytic decomposition reaction system using non-isothermal DSC is presented. Information is obtained on th... A method of estimating the critical rate of temperature increase of thermal explosion for the first orderautocatalytic decomposition reaction system using non-isothermal DSC is presented. Information is obtained on theincreasing rate of temperature in nitrocellulose containing 13.54% of nitrogen when the first order autocatalytic decomposition converts into thermal explosion. 展开更多
关键词 DSC NITROCELLULOSE increasing rate of temperature NON-ISOTHERMAL
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Characteristic Analysis of DS18B20 Temperature Sensor in the High-voltage Transmission Lines’ Dynamic Capacity Increase
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作者 Song Nie Yang-chun Cheng Yuan Dai 《Energy and Power Engineering》 2013年第4期557-560,共4页
Dynamic capacity increase in high voltage electric power transmission line is currently the most economical method for solving electric power transmission bottleneck nowadays. DS18B20 temperature sensor is applied to ... Dynamic capacity increase in high voltage electric power transmission line is currently the most economical method for solving electric power transmission bottleneck nowadays. DS18B20 temperature sensor is applied to the dynamic capacity increase of high voltage transmission lines to measure the conductor temperature and ambient temperature. The paper is focused on the experiment of DS18B20 both in the laboratory and outside. From the result of the lab temperature measurement data analysis, using 4 DS18B20’s is the most suitable plan, considering both accuracy and economical efficiency. In the experiment outside, we get four groups of conductor (uncharged) temperature and four groups of ambient temperature. The data proved that DS18B20 has good stability, and small measurement error. It is suitable for measuring the temperature of conductor and ambient in dynamic capacity increase, and helpful to improve the accuracy of the calculation of capacity increasing. 展开更多
关键词 DS18B20 temperature SENSOR Measurement ERROR DYNAMIC Capacity increase Data Analysis
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PRELIMINARY STUDY OF INDOOR FEATURES OF TEMPERATURE AND HUMIDITY FOR ROOMS FACING NORTH-SOUTH IN WINTER IN A LOW-LATITUDE PLATEAU CITY
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作者 张一平 李佑荣 +2 位作者 王进欣 刘玉洪 马友鑫 《Journal of Tropical Meteorology》 SCIE 2002年第1期85-92,共8页
Analyzing observations of wintertime air temperature in both indoor and outdoor surroundings in Kunming, a city lying in low latitudes, characteristics of temperature and humidity have been studied for the interior of... Analyzing observations of wintertime air temperature in both indoor and outdoor surroundings in Kunming, a city lying in low latitudes, characteristics of temperature and humidity have been studied for the interior of rooms facing north-south under different weather conditions. Significant warming effect has been identified in terms of lowest and daily-mean indoor temperature in the area of Kunming. The heating amplitude ranges from 7.7C to 10.0C and from 4.6C to 5.8C for the interior part of rooms facing the south and from 4.6C to 7.0C and from 1.3C to 4.4C for the interior part of rooms facing the north, respectively for the two elements. The highest air temperature is higher indoor than outdoor for rooms facing the south, but otherwise is usually true for rooms facing the north. Additional findings point out that buildings not only help maintain relatively warm indoor temperature but delay its variation. The diurnal cycle of temperature indoor is smaller and ranges by 40% ~ 48% for south-facing rooms, and by 20% ~ 30% for north-facing rooms, than outdoor, and the highest temperature is about 2 hours late inside the room than outside. It shows how inertly indoor temperature varies. The work also finds that relative humidity is less indoor in southward rooms than in northward ones and difference is the largest on fine days but the smallest when it is overcast. For the diurnal variation, the indoor relative humidity is large at nighttime with small amplitude but small during daytime with large amplitude. The above-presented results can be served as scientific foundation for more research on climate in low-latitude cities and rational design of urban architectures. 展开更多
关键词 orientation of room air temperature and humidity different weather condition WINTER low-latitude plateau city
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Microwave absorbing characteristics and temperature increasing behavior of basic cobalt carbonate in microwave field
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作者 刘秉国 彭金辉 +4 位作者 张利波 SRINIVASAKANNAN C 黄铭 张泽彪 郭胜惠 《Journal of Central South University》 SCIE EI CAS 2010年第6期1211-1215,共5页
The microwave absorbing characteristics of basic cobalt carbonate,cobalt oxide(Co3O4),and the mixture of basic cobalt carbonate and cobalt oxide were investigated by means of microwave cavity perturbation,their temper... The microwave absorbing characteristics of basic cobalt carbonate,cobalt oxide(Co3O4),and the mixture of basic cobalt carbonate and cobalt oxide were investigated by means of microwave cavity perturbation,their temperature increasing curves were measured,and their ability to absorb microwave energy was also assessed based on the temperature increasing behavior of the material exposed to microwave field.Analyses of spectrum attenuation and relative frequency shift show that basic cobalt carbonate has weak capability to absorb microwave energy,while cobalt oxide has very strong capability to absorb microwave energy.It is feasible to thermally decompose basic cobalt carbonate though addition of small amount of cobalt oxide in microwave fields.The capability to absorb microwave energy of sample increases with an increase in mixing ratio of Co3O4. 展开更多
关键词 basic cobalt carbonate cobalt oxide (Co3O4) MICROWAVE temperature increasing behavior absorption
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Effect of temperature on dielectric property and microwave heating behavior of low grade Panzhihua ilmenite ore 被引量:10
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作者 刘晨辉 张利波 +4 位作者 彭金辉 刘秉国 夏洪应 顾晓春 史谊峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3462-3469,共8页
The permittivity of low grade Panzhuhua ilmenite ore at 2.45 GHz in the temperatures from 20 ℃ up to 100 ℃ was measured using the technology of open-ended coaxial sensor combined with theoretical computation. The re... The permittivity of low grade Panzhuhua ilmenite ore at 2.45 GHz in the temperatures from 20 ℃ up to 100 ℃ was measured using the technology of open-ended coaxial sensor combined with theoretical computation. The results show that both the real (ε′) and imaginary (ε′) part of complex permittivity (ε′-jε′) of the ilmenite significantly increase with temperature. The loss tangent (tanδ) is a quadratic function of temperature, and the penetration depth of ilmenite decreases with temperature increase from 20 ℃to 100 ℃ The increase of the sample temperature under microwave radiation displays a nonlinear relationship between the temperature (T) and microwave heating time (t). The positive feedback interaction between complex permittivity and sample temperature amplifies the interaction between ilmenite and the microwave radiation. The optimum dimensions for uniform heat deposition vary from 10 cm to 5 cm (about two power penetration depths) in a sample being irradiated from both sides in a 2.45 GHz microwave field when temperature increases from room temperature to 100 ℃ 展开更多
关键词 dielectric properties Panzhihua ilmenite low grade microwave heating temperature increase
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Long Term Temperature Trends at Major, Medium, Small Cities and Hill Stations in India during the Period 1901-2013 被引量:2
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作者 Dilip Rajaram Kothawale Nayana Rajendra Deshpande Rupa Kumar Kolli 《American Journal of Climate Change》 2016年第3期383-398,共16页
Industrialization and urbanization are the most dominant causal factors for long-term changes in surface air temperatures. To examine this fact, the long term changes in the surface-air temperatures have been evaluate... Industrialization and urbanization are the most dominant causal factors for long-term changes in surface air temperatures. To examine this fact, the long term changes in the surface-air temperatures have been evaluated by the linear trend for the different periods, i.e. 1901-2013, 1901-1970 and recent period 1971-2013 as rapid industrialization was observed during the recent four decades. In the present study, seasonal and annual mean, maximum and minimum temperature data of 36 stations for the period 1901-2013 have been used. These stations are classified into 4 groups, namely major, medium, small cities and hill stations. During the period 1901-1970, less than 50% stations from each group showed a significant increasing trend in annual mean temperature, whereas in the recent period 1971-2013, more than 80% stations from all the groups except small city group showed a significant increasing trend. The minimum temperature increased faster than that of the maximum temperature over major and medium cities, while maximum temperature increased faster than the minimum temperature over the small cities and hill stations. The annual mean temperature of all the coastal stations showed a significant increasing trend and positive correlation with Precipitable Water Vapour (PWV). The effect of PWV is more pronounced on minimum temperature than that of the maximum. 展开更多
关键词 increasing Trend Decreasing Trend temperature Anomalies Aerosol Index Precipitable Water Vapour
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Perioperative outcomes of different temperature management in pediatric aortic arch surgery:a single center 8-year experience
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作者 Yuanyuan Tong Jinping Liu +1 位作者 Ruoning Lv Yu Jin 《中国循环杂志》 CSCD 北大核心 2018年第S01期171-171,共1页
Objective With the widespread application of regional low flow perfusion, deep hypothermia is non-essential for organ protection;therefore, there is a growing tendency to increase systemic temperature.
关键词 different temperature low flow PERFUSION increase SYSTEMIC temperature
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超材料天线罩温度升高快速分析
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作者 张强 孙红兵 +4 位作者 李钊 周浩 钱吉裕 唐守柱 李洋 《现代雷达》 CSCD 北大核心 2024年第3期21-27,共7页
随着电子系统的功率越来越高,必须考虑超材料天线罩中温度升高。由于超材料天线罩的复杂性,其温度升高分析难度更大。超材料天线罩的热分析涉及电磁场和温度场的多物理场的分析,对于电大尺寸的天线罩,模型复杂,计算时间很长。文中首先... 随着电子系统的功率越来越高,必须考虑超材料天线罩中温度升高。由于超材料天线罩的复杂性,其温度升高分析难度更大。超材料天线罩的热分析涉及电磁场和温度场的多物理场的分析,对于电大尺寸的天线罩,模型复杂,计算时间很长。文中首先进行了系统的理论分析,然后给出了天线罩内部温度升高的快速方法,先后计算了单层超材料天线罩、夹层超材料天线罩的最大温度升高和温度升高分布,计算结果与实测及全波仿真符合较好,与全波分析相比计算时间大大缩短,速度提高数百倍。该方法物理概念清晰,快速简便,还能够迅速分析存在环境温度差情况下的超材料天线罩的温度升高分布,为大功率系统中的超材料天线罩设计提供有力的支撑。 展开更多
关键词 天线罩 超材料 温度升高 快速分析 降本增效
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光热站辅助生物质燃气炉燃烧与升负荷优化大涡模拟
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作者 李想 戚胜 《化学工程》 CAS CSCD 北大核心 2024年第7期14-19,共6页
生物质燃气炉设计对于提高低碳能源整合利用具有重要价值,采用LES(大涡模拟)方法,分析热管区温度分布及升负荷时出口参数变化,提出敏感温度T_(a),并分析燃料增加比b对其影响,以焓降分析底部燃烧口角度及位置的影响,得出结论:增加底部入... 生物质燃气炉设计对于提高低碳能源整合利用具有重要价值,采用LES(大涡模拟)方法,分析热管区温度分布及升负荷时出口参数变化,提出敏感温度T_(a),并分析燃料增加比b对其影响,以焓降分析底部燃烧口角度及位置的影响,得出结论:增加底部入口后,烟气流动更加顺畅,热管进、出口管温度不均情况缓解明显。在升负荷时,烟气分布更加均匀,换热均匀性提升。b=3时,流量差异较小。当底部入口角度为60°,距离热管区域距离为0.135 m时,效果最佳。整体上,增加底部燃烧口在提升设备的运行效率的同时,能够显著改善运行安全性,具有较高的应用价值。 展开更多
关键词 生物质燃气炉 底部燃烧口 温度分布 升负荷 焓降 大涡模拟
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深井高速涡轮钻配套同径取心技术研究
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作者 闫家 梁健 +6 位作者 王文 王瑜 张凯 张恒春 曹龙龙 吴纪修 王志刚 《钻探工程》 2024年第4期23-30,共8页
分析了涡轮钻具结构特征及性能特点,在深井、特深井的高温高压、强研磨性地层中,涡轮钻具基本上成为唯一可选的用于复合钻进提速降本的井下动力钻具。针对深部资源的勘探开发需求,阐述了现有涡轮钻具同径取心技术的优势及存在的问题,利... 分析了涡轮钻具结构特征及性能特点,在深井、特深井的高温高压、强研磨性地层中,涡轮钻具基本上成为唯一可选的用于复合钻进提速降本的井下动力钻具。针对深部资源的勘探开发需求,阐述了现有涡轮钻具同径取心技术的优势及存在的问题,利用数值模拟仿真技术分析和研究了涡轮钻具同径取心过程中钻井液的流动状态对取心效果的影响,认识到涡轮钻具可耐高温,适于深井、特深井全面钻进及取心钻进,但其高转速在取心钻进过程也容易造成岩心磨损、岩柱螺旋,而改善同径取心钻具高速单动性能、加长涡轮钻具螺旋稳定器、利用反螺旋扰流板等技术措施,有利于减小取心钻具井底的涡动、降低岩心内外管轴向速度差,从而提高涡轮钻同径取心钻进的岩心质量。 展开更多
关键词 特深井 高温硬岩 涡轮钻具 同径取心 提速降本 数值模拟 玛页1井
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温度和砷对不同品种水稻幼苗生长和砷吸收的影响
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作者 翟伊然 李仁英 +4 位作者 张婍 祁梦如 卢炳浩 黄利东 徐向华 《土壤学报》 CAS CSCD 北大核心 2024年第4期1156-1165,共10页
为明确温度和外源砷对水稻生长发育的影响,选取江苏地区常见的8个水稻品种为试验材料,通过添加不同浓度外源砷[0(As0)、0.5(As0.5)和1mg·L^(–1)(As1)]和模拟不同温度[白天/夜晚分别为30℃/25℃(T0)和35℃/30℃(T1)],在人工气候箱... 为明确温度和外源砷对水稻生长发育的影响,选取江苏地区常见的8个水稻品种为试验材料,通过添加不同浓度外源砷[0(As0)、0.5(As0.5)和1mg·L^(–1)(As1)]和模拟不同温度[白天/夜晚分别为30℃/25℃(T0)和35℃/30℃(T1)],在人工气候箱内进行了发芽和苗期培养试验,并分析了8个品种水稻种子萌发、幼苗生长及砷含量状况。结果表明,外源砷对水稻的芽长和活力指数具有抑制作用,与对照(T0As0)相比,T0As1处理使不同品种水稻的芽长和活力指数分别降低13.69%~43.34%和28.14%~52.88%。而温度对水稻种子萌发的影响与水稻品种有关。在T1处理下,盐两优1618的发芽率、芽长和活力指数均优于其他品种。温度和外源砷的共同作用显著降低了不同品种水稻的芽长(P<0.05)。与T0As0相比,T1As1使水稻芽长显著降低5.66%~43.34%。水稻根长和根系活力显著受到温度和外源砷的单一因素的影响。与T0As0相比,T0As1处理使水稻根系活力降低3.01%~58.21%。温度和外源砷的共同作用抑制了水稻根长和根系活力,其中T1As1使水稻根系活力显著降低53.80%~89.01%。不同品种水稻的苗高和根系活力在相同温度或外源砷处理下具有显著差异(P<0.05),其中盐两优888的苗高和根系活力均处于较高水平。水稻茎叶砷含量在外源砷处理下显著增加,在增温处理下却降低。与单一的砷处理相比,温度和外源砷的共同作用降低了水稻茎叶的砷含量。综上可知,温度和外源砷影响水稻的生长及砷吸收,但水稻生长状况具有明显的品种间差异,其中盐两优888和盐两优1618在增温和外源砷共存条件下的种子萌发和生长状况优于其他水稻品种。 展开更多
关键词 水稻 增温 生长 发芽 砷吸收
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基于分子动力学的升温条件下煤中锂吸附扩散特性研究
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作者 张俊爽 张彬 +1 位作者 孙蓓蕾 刘超 《地质学报》 EI CAS CSCD 北大核心 2024年第8期2499-2508,共10页
煤是特殊的沉积有机岩石,在其形成过程中可以富集战略性金属,并在煤系中形成大型或超大型金属矿床,成为矿产资源勘探的重要领域。温度是影响煤化作用及其过程中锂等关键金属赋存方式变化的重要因素。为了研究升温过程对煤中锂吸附特征... 煤是特殊的沉积有机岩石,在其形成过程中可以富集战略性金属,并在煤系中形成大型或超大型金属矿床,成为矿产资源勘探的重要领域。温度是影响煤化作用及其过程中锂等关键金属赋存方式变化的重要因素。为了研究升温过程对煤中锂吸附特征的影响,本文以内蒙古准格尔煤田典型高锂煤为研究对象,构建锂-煤可视化模型,通过分子动力学方法计算了不同温度点锂在煤结构中的径向分布函数、扩散系数,分析了锂与有机大分子结构和高岭石相互作用能的变化,探讨了煤结构对锂的吸附特征。结果表明:锂在吸附过程中与氮原子、有机结构中的氧原子和硅原子存在较强的相互作用,与其他原子相互作用较弱或者不存在相互作用。锂与氮原子和有机结构中的氧原子主要是通过氢键作用吸附,而与硅原子则存在静电力和范德华力作用。从20℃升温到300℃的过程中,锂扩散系数受到温度和煤结构变化的影响,呈现出先升高后降低的趋势;煤结构对锂的吸附作用能以静电能为主。 展开更多
关键词 准格尔煤田 分子动力学 升温 吸附特征
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滨海地区增温对水稻产量及稻米品质的影响
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作者 杜萌 马凌霄 +1 位作者 隋鑫 安迪 《北方水稻》 CAS 2024年第5期25-28,共4页
为探究滨海地区增温对水稻产量及稻米品质的影响,以“盐粳476”、“盐粳313”为试验材料,设增温(增加2℃)、常温对照两个处理进行试验。结果表明:水稻花粉不育率增温处理盐粳476为15.18%、盐粳313为12.56%;增温处理盐粳476产量为277.81 ... 为探究滨海地区增温对水稻产量及稻米品质的影响,以“盐粳476”、“盐粳313”为试验材料,设增温(增加2℃)、常温对照两个处理进行试验。结果表明:水稻花粉不育率增温处理盐粳476为15.18%、盐粳313为12.56%;增温处理盐粳476产量为277.81 kg/667 m^(2)、盐粳313产量388.36 kg/667 m^(2),比相对应的CK处理大幅减产,分别减产231.89 kg/667 m^(2)、265.3 kg/667 m^(2);增温处理的加工品质大体呈下降的趋势,增温处理相比于对应CK处理食味值降低、直链淀粉含量和蛋白质含量升高。 展开更多
关键词 水稻 增温 育性 产量 品质
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浸种和增温对赤皮青冈种子萌发及内源激素含量影响
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作者 林昱堃 徐卫可 +3 位作者 吴仁超 苏光浪 周志春 王斌 《西部林业科学》 CAS 北大核心 2024年第4期35-42,共8页
为分析浸种和增温处理下赤皮青冈种子萌发节律和内源激素含量变化规律,探索种子打破休眠的机制,采用双因素析因试验设计,通过浸种和增温处理对赤皮青冈种子进行萌发试验,统计发芽情况并定期测定种子的内源激素含量。结果显示:增温播种... 为分析浸种和增温处理下赤皮青冈种子萌发节律和内源激素含量变化规律,探索种子打破休眠的机制,采用双因素析因试验设计,通过浸种和增温处理对赤皮青冈种子进行萌发试验,统计发芽情况并定期测定种子的内源激素含量。结果显示:增温播种与浸种48 h的处理组合种子发芽率最高,达到最高发芽势的时间最短,在增温播种处理下种子的萌发时间提前。不同内源激素对浸种和增温的响应不同,其中增温播种配合浸种可以降低种子在萌发末期生长素(IAA)的含量,有助于赤皮青冈种子萌发。赤霉素(GA_(3))含量在不同播种温度下均呈波动上升趋势;反式玉米素(TZR)含量在大棚播种处理下呈先下降后上升趋势,而增温播种处理下则呈先上升后下降趋势;增温处理下,茉莉酸(JA)含量总体呈下降趋势;4月末水杨酸(SA)含量在不同播种温度下均为浸种48 h含量最高,浸种24 h含量最低。TZR含量基本不受浸种处理影响。GA_(3)/ABA和TZR/ABA比值的增加均能促进赤皮青冈种子解除休眠。相关性分析显示,3月份TZR和GA_(3)呈显著正相关,TZR和SA呈显著负相关,4月份各激素之间的相关性明显下降。结果表明,增温处理有助于赤皮青冈种子萌发,若配合48 h浸种可以打破种皮界限,提高种子发芽率,并且使种子萌发达到最大发芽势的时间提前。 展开更多
关键词 赤皮青冈 种子萌发 内源激素 浸种 增温
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2022年夏季武汉市三类空间气温时空变化分析
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作者 刘火胜 昝嘉惠 +2 位作者 成雅田 余乾慧 吴昌广 《气象与环境学报》 2024年第2期51-58,共8页
选用2022年6—8月武汉市都市发展区89个自动气象站逐时气温观测资料,分析该地区夏季三类空间(城镇、农业、生态)夏季不同天气条件下的气温变化,探究高温天气事件对三类空间气温的空间分布及生态、农业空间对城镇空间气温的影响。结果表... 选用2022年6—8月武汉市都市发展区89个自动气象站逐时气温观测资料,分析该地区夏季三类空间(城镇、农业、生态)夏季不同天气条件下的气温变化,探究高温天气事件对三类空间气温的空间分布及生态、农业空间对城镇空间气温的影响。结果表明:高温日、非高温日的城镇、农业、生态三类空间气温均为05—06时逐时平均气温最低,14—16时最高的昼间变化趋势。高温天气事件显著增加了三类空间的夜间气温,其中城镇空间的夜间气温增幅最大,为4.5℃。三类空间气温类间差异在高温日最大,在阴雨日最小。三类空间气温在高温日和非高温日的夜间均存在显著的空间分布异质性,形成了气温由中心城区向边缘区逐渐递减的圈层结构,而三类空间的昼间气温差异较小。高温日、非高温日的生态、农业空间对其临近城镇空间的降温作用在日出前后、夜间最显著,两类空间对城镇空间的降温强度在高温日大于非高温日。 展开更多
关键词 高温日 气温增幅 气温差
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基于增温敏感性指数的城市功能区升温效应空间分异研究
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作者 杨慧 徐伟铭 +2 位作者 邵尔辉 廖云婷 林馨 《热带地理》 CSCD 北大核心 2024年第3期557-568,共12页
利用福州市三环内的POI数据和Place2vec模型识别城市功能区,并在此基础上分析各功能区的热场等级空间分异特征,借助增强回归树算法(Boosting Regression Tree, BRT)构建功能区增温敏感性指数,对不同功能区在地表升温过程中的敏感性差异... 利用福州市三环内的POI数据和Place2vec模型识别城市功能区,并在此基础上分析各功能区的热场等级空间分异特征,借助增强回归树算法(Boosting Regression Tree, BRT)构建功能区增温敏感性指数,对不同功能区在地表升温过程中的敏感性差异进行定量测度,进而对区域尺度上的城市热环境空间分异机制进行深入探讨。结果表明:1)基于Place2vec模型的城市功能区识别结果具有较高的精度;2)除绿地与广场区外的4类功能区均具有高温现象,其中产业区的热场强度最高;3)各类功能区整体增温敏感性由高至低依次是:产业区、生活服务与住宅区、商业区、公共管理与服务区、绿地与广场区;不同升温阶段的功能区增温敏感性存在差异,在高温梯度下差异显著;地表覆被增温敏感性具有明显的功能区域分异特征。 展开更多
关键词 城市功能区 城市热环境 地表升温 增温敏感性 Place2vec模型 BRT算法 福州市
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