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Enhanced ferroelectric and improved leakage of BFO-based thin films through increasing entropy strategy
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作者 Dongfei Lu Guoqiang Xi +5 位作者 Hangren Li Jie Tu Xiuqiao Liu Xudong Liu Jianjun Tian Linxing Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2263-2273,共11页
BiFeO_(3)(BFO)has received considerable attention as a lead-free ferroelectric film due to its large theoretical remnant polariza-tion.However,BFO suffers from a large leakage current,resulting in poor ferroelectric p... BiFeO_(3)(BFO)has received considerable attention as a lead-free ferroelectric film due to its large theoretical remnant polariza-tion.However,BFO suffers from a large leakage current,resulting in poor ferroelectric properties.Herein,the sol-gel method was used to deposit a series of BFO-based thin films on fluorine-doped tin oxide substrates,and the effects of the substitution of the elements Co,Cu,Mn(B-site)and Sm,Eu,La(A-site)on the crystal structure,ferroelectricity,and leakage current of the BFO-based thin films were invest-igated.Results confirmed that lattice distortion by X-ray diffraction can be attributed to the substitution of individual elements in the BFO-based films.Sm and Eu substitutions contribute to the lattice distortion in a pseudo-cubic structure,while La is biased toward pseudo-tet-ragonal.Piezoelectric force microscopy confirmed that reversible switching of ferroelectric domains by nearly 180°can be realized through the prepared films.The ferroelectric hysteresis loops showed that the order for the polarization contribution is as follows:Cu>Co>Mn(B-site),Sm>La>Eu(A-site).The current density voltage curves indicated that the order for leakage contribution is as follows:Mn<Cu<Co(B-site),La<Eu<Sm(A-site).Scanning electron microscopy showed that the introduction of Cu elements facilitates the formation of dense grains,and the grain size distribution statistics proved that La element promotes the reduction of grain size,leading to the increase of grain boundaries and the reduction of leakage.Finally,a Bi_(0.985)Sm_(0.045)La_(0.03)Fe_(0.96)Co_(0.02)Cu_(0.02)O_(3)(SmLa-CoCu)thin film with a qualitative leap in the remnant polarization from 25.5(Bi_(0.985)Sm_(0.075)FeO_(3))to 98.8µC/cm^(2)(SmLa-CoCu)was prepared through the syner-gistic action of Sm,La,Co,and Cu elements.The leakage current is also drastically reduced from 160 to 8.4 mA/cm^(2)at a field strength of 150 kV/cm.Thus,based on the increasing entropy strategy of chemical engineering,this study focuses on enhancing ferroelectricity and decreasing leakage current,providing a promising path for the advancement of ferroelectric devices. 展开更多
关键词 increasing entropy SYNERGISTIC ferroelectric film remnant polarization leakage current
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Factors responsible for the increasing trend of mei-yu season rainfall during 1979-2020 over the western and eastern mei-yu domain 被引量:1
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作者 Xuejie Zhao Guoxiong Wu +2 位作者 Jiangyu Mao Yimin Liu Bian He 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第3期27-32,共6页
近几十年来,江淮流域梅雨监测区(MMD)的梅雨期(6-7月)降水呈增加趋势.本文基于1979-2020年台站观测降水资料和ERA5再分析数据,从大气环流变异的角度揭示了这种长期增加趋势的主要影响因素.发现在MMD范围内,梅雨期降水趋势的增幅东部大... 近几十年来,江淮流域梅雨监测区(MMD)的梅雨期(6-7月)降水呈增加趋势.本文基于1979-2020年台站观测降水资料和ERA5再分析数据,从大气环流变异的角度揭示了这种长期增加趋势的主要影响因素.发现在MMD范围内,梅雨期降水趋势的增幅东部大于西部.水汽收支定量诊断表明,异常的蒸发和水汽平流对MMD西部和东部降水增加趋势的相对贡献是不同的.MMD西部(东部)的降水趋势主要归咎于增强的局地蒸发(增强的垂直水汽平流),后者又取决于MMD对流层中,低层的异常气旋环流.这种位于气候平均的西太平洋副热带高压西北侧的异常气旋有助于MMD东部600 hPa以上的水汽辐散增加,伴随加强的850 hPa水汽辐合,从而导致垂直水汽平流的增强.相反,该异常气旋则有利于增强MMD西部的局地蒸发. 展开更多
关键词 梅雨期降水 增加趋势 蒸发 水汽平流
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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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The Effects of Increasing Production of Endophytes Phomopsis B3 on Rice 被引量:18
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作者 戴传超 袁志林 +2 位作者 杨启银 史青山 李霞 《Agricultural Science & Technology》 CAS 2008年第1期39-42,48,共5页
After insufflating extended endophytes phomopsis B3 ferment diluent on seedling bed of rice, the effect of microbial inoculum on rice growth was studied. The investigation result of seedlings before transplanting seed... After insufflating extended endophytes phomopsis B3 ferment diluent on seedling bed of rice, the effect of microbial inoculum on rice growth was studied. The investigation result of seedlings before transplanting seedling showed that leaf age,the number of green leaves,the number of tiller of individual plant and the weight of per 100 fresh plants in microbial inoculum treatment group increased 0.11,0.12 ,0. 03 and 2.6 g respectively compared with those of control group. 20 days after transplanting, increased tiller number in microbial inoculum treatment group was 55 500 hm^2 more than that in control group. 30 days after transplanting, tiller number in microbial inoculum treatment group was 42 000 hm^2 more than that in control group. In harvest season, the yield ,weight of I 0130 grain and seed-setting rate increased 300 kg/hm2, 0. 7 g and 0. 23% respectively compared with these in control group. The result of preliminary study demonstrated that microbial inoculum confected by endophytes phomopsis B3 could increase the number of strong seedling and yield. 展开更多
关键词 ENDOPHYTES PHOMOPSIS RICE Yield increasing Strong seedling
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Construction controlling and strength increasing characteristics of locally developed epoxy asphalt mixture 被引量:7
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作者 陈春 钱振东 陈磊磊 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期61-64,共4页
The construction controlling elements,including construction performance at low ambient temperatures,reserved time ranges,and the strength increasing rule,for locally developed epoxy asphalt mixture(LDEAM) are studi... The construction controlling elements,including construction performance at low ambient temperatures,reserved time ranges,and the strength increasing rule,for locally developed epoxy asphalt mixture(LDEAM) are studied through laboratory tests.Air void and Marshall stability are chosen as the performance measures for evaluating the construction quality.The wheel rolling test is used to simulate the actual construction situations,while the Marshall test and the Brookfield viscosity test are adopted to study the strength increasing rule.The experimental results reveal that the LDEAM can be constructed under a low ambient temperature condition of 10℃,and its longest reserved time is 70 min at a reserved temperature of 120℃.Test also shows that the strength of the LDEAM increases with time and temperature before cured.Finally,the theoretical reason for the strength increasing rule is analyzed on the basis of the organic chemistry theory. 展开更多
关键词 construction characteristics locally developed epoxy asphalt strength increasing characteristics
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DUAL RANDOM MODEL OF INCREASING ANNUITY 被引量:6
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作者 He Wenjiong Zhang YiEconomic College & Science College, Zhejiang Univ.(Xixi Campus),Hangzhou 310028. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第4期430-438,共9页
The dual random models about the life insurance and social pension insurance have received considerable attention in the recent articles on actuarial theory and applications. This paper discusses a general kind of inc... The dual random models about the life insurance and social pension insurance have received considerable attention in the recent articles on actuarial theory and applications. This paper discusses a general kind of increasing annuity based on its force of interest accumulation function as a general random process. The dual random model of the present value of the benefits of the increasing annuity has been set, and their moments have been calculated under certain conditions. 展开更多
关键词 increasing annuity random model independent increment process.
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SIMULATING THE RESPONSE OF NON-UNIFORMITY OF PRECIPITATION EXTREMES OVER CHINA TO CO_2 INCREASING BY MIROC_HIRES MODEL 被引量:4
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作者 朱坚 黄丹青 +1 位作者 周鹏 林惠娟 《Journal of Tropical Meteorology》 SCIE 2013年第4期331-339,共9页
The response of non-uniformity of precipitation extremes over China to doubled CO2has been analyzed using the daily precipitation simulated by a coupled general circulation model,MIROC_Hires.The major conclusions are ... The response of non-uniformity of precipitation extremes over China to doubled CO2has been analyzed using the daily precipitation simulated by a coupled general circulation model,MIROC_Hires.The major conclusions are as follows:under the CO2increasing scenario(SRES A1B),the climatological precipitation extremes are concentrated over the southern China,while they are uniformly distributed over the northern China.For interannual variability,the concentration of precipitation extremes is small over the southern China,but it is opposite over the northern China.The warming effects on the horizontal and vertical scales are different over the northern and southern part of China.Furthermore,the atmospheric stability is also different between the two parts of China.The heterogeneous warming is one of the possible reasons for the changes in non-uniformity of precipitation extremes over China. 展开更多
关键词 precipitation EXTREMES concentration density and PERIOD CO2 increasE asymmetric pattern
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Survey on Influence of Tourism Development on Ensuring Supply and Increasing Income of Farmers in Nyingchi 被引量:3
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作者 Hongmei GONG Lianjiu SONG 《Asian Agricultural Research》 2015年第8期48-52 56,56,共6页
Tourism is an essential industry promoting economic development of Nyingchi and also plays a great role in national economy. Increasing people's income and improving living conditions are starting points of promot... Tourism is an essential industry promoting economic development of Nyingchi and also plays a great role in national economy. Increasing people's income and improving living conditions are starting points of promoting tourism development. This survey indicates that tourism in Nyingchi develops rapidly,growth rate of tourists is slightly lower than growth rate of income,and per capita tourist consumption is also increasing. Comparative analysis indicates that tourist resources,traffic condition,tourism propaganda intensity,development intensity of relevant products,and seasonal factor have significant influence on ensuring supply and increasing income of farmers. Further analysis shows that low educational level,weak basic tourism knowledge,backward tourism sanitation,and lagging tourist service infrastructure are major problems and obstacles. Resource advantages of scenic spots,setting foot on structural adjustment of characteristic industry,developing specialized farmer cooperatives and leading enterprises,and deeply exploring intension of tourist culture are major approaches for ensuring supply and increasing income of farmers. In sum,it is urgent and important to strengthen ability of ensuring supply and increasing income in improving people's living conditions and promoting tourism development. 展开更多
关键词 Nyingchi TOURISM Ensuring supply and increasing in
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Forecasting increasing rate of power consumption based on immune genetic algorithm combined with neural network 被引量:1
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作者 杨淑霞 《Journal of Central South University》 SCIE EI CAS 2008年第S2期327-330,共4页
Considering the factors affecting the increasing rate of power consumption, the BP neural network structure and the neural network forecasting model of the increasing rate of power consumption were established. Immune... Considering the factors affecting the increasing rate of power consumption, the BP neural network structure and the neural network forecasting model of the increasing rate of power consumption were established. Immune genetic algorithm was applied to optimizing the weight from input layer to hidden layer, from hidden layer to output layer, and the threshold value of neuron nodes in hidden and output layers. Finally, training the related data of the increasing rate of power consumption from 1980 to 2000 in China, a nonlinear network model between the increasing rate of power consumption and influencing factors was obtained. The model was adopted to forecasting the increasing rate of power consumption from 2001 to 2005, and the average absolute error ratio of forecasting results is 13.521 8%. Compared with the ordinary neural network optimized by genetic algorithm, the results show that this method has better forecasting accuracy and stability for forecasting the increasing rate of power consumption. 展开更多
关键词 IMMUNE GENETIC algorithm neural network power CONSUMPTION increasing RATE FORECAST
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Modeling the Roles of Precipitation Increasing in Glacier Systems Responding to Climate Warming—Taking Xinjiang Glaciated Region as Example 被引量:3
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作者 WANG Xin XIE Zichu +3 位作者 LIU Shiyin TAO Jianjun HAN Yongshun YANG Yuelong 《Journal of Mountain Science》 SCIE CSCD 2005年第4期306-312,共7页
The studies on prediction of climate in Xinjiang almost show that the precipitation would increase in the coming 50 years, although there were surely some uncertainties in precipitation predictions. On the basis of th... The studies on prediction of climate in Xinjiang almost show that the precipitation would increase in the coming 50 years, although there were surely some uncertainties in precipitation predictions. On the basis of the structure of glacier system and nature of equilibrium line altitude at steady state (ELAo), a functional model of the glacier system responding to climate changes was established, and it simultaneously involved the rising of summer mean temperature and increasing of mean precipitation. The results from the functional model under the climatic scenarios with temperature increasing rates of 0.01, 0.03 and 0.05 K/year indicated that the precipitation increasing would play an evident role in glacier system responding to climate change: if temperature become 1 ℃ higher, the precipitation would be increased by 10%, which can slow down the glaciers retreating rate in the area by 4 %, accelerate runoff increasing rate by 8 % and depress the ELAo rising gradient by 24 m in northern Xinjiang glacier system where semi-continental glaciers dominate, while it has corresponding values of only 1%, 5 % and 18m respectively in southern Xinjiang glacier system, where extremely continental glaciers dominate. 展开更多
关键词 Glacier system climate warming precipitation increasing role
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The Buffer Capability of the Ocean to Increasing Atmospheric CO_2 被引量:7
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作者 徐永福 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第4期501-510,共10页
The CO_2-seawater system and the method for calculating the partial pressure of CO2 (pCO2) in seawater are studied. The buffer capability of the ocean to increasing atmospheric CO2 is expressed in terms of the differe... The CO_2-seawater system and the method for calculating the partial pressure of CO2 (pCO2) in seawater are studied. The buffer capability of the ocean to increasing atmospheric CO2 is expressed in terms of the differential buffer factor and buffer index. Dissolutions of aragonite and calcite have a significant inffluence on the differential buffer factor. The trend of change in the buffer factor is obtained by a box model. 展开更多
关键词 The Buffer Capability of the Ocean to increasing Atmospheric CO2 CO
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FIXED POINTS OF INCREASING OPERATORS IN ORDERED SPACE WITH APPLICATIONS 被引量:1
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作者 YANG Guang-chong(杨光崇) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第3期341-349,共9页
The minimal-maximal fixed points theorems of increasing operators are proved in ordered space and some well-known results of increasing operators and monotone operators are improved and generalized. The obtained resul... The minimal-maximal fixed points theorems of increasing operators are proved in ordered space and some well-known results of increasing operators and monotone operators are improved and generalized. The obtained results are then applied to singular nonlinear boundary problem in ordinary differential equation without any assumption of continuity, compactness, convexity and concavity. 展开更多
关键词 ordered space supremum and infimum increasing operator and fixed point singular boundary problem
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Effect of Increasing Course of Temperature and Pressure on Polypropylene Degradation in Supercritical Water 被引量:2
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作者 苏磊 吴学华 +3 位作者 刘秀茹 陈丽英 陈克宇 洪时明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第5期738-741,共4页
The effect of increasing course of temperature and pressure on polypropylene (PP) degradation in supercritical water was investigated for developing a process of recycling waste plastic. A group of experiments was c... The effect of increasing course of temperature and pressure on polypropylene (PP) degradation in supercritical water was investigated for developing a process of recycling waste plastic. A group of experiments was carded out in a reaction system at a pressure of 26MPa, temperature of 380℃ or 400℃ for 30min, 70min, and 120min by Course One (the increasing course of temperature and pressure is via gaseous regions to supercritical regions), and the other group was carried out at corresponding holding conditions by Course Two (the increasing course of temperature and pressure is via liquid regions to supercritical regions). The time of the increasing courses was about 30min. Products were analyzed by Ostward-type viscometer, gaseous chromatography, and mass spectrometers (GC/MS). Characterization results suggested that different increasing courses of temperature and pressure would give rise to different results, although they were treated under the similar holding conditions. It was also found that Course Two was more effective on PP degradation in supercritical water. 展开更多
关键词 increasing course polypropylene degradation supercritical water
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Effect of Agricultural Comprehensive Development on Increasing Income of Farmers in Jiangsu Hilly and Mountainous Areas 被引量:1
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作者 Tuzhan WANG 《Asian Agricultural Research》 2015年第12期37-40,共4页
To adapt to rural and agricultural economic development,Jiangsu Province adjusted main task of comprehensive development of hilly and mountainous areas to supporting and promoting agricultural structural adjustment of... To adapt to rural and agricultural economic development,Jiangsu Province adjusted main task of comprehensive development of hilly and mountainous areas to supporting and promoting agricultural structural adjustment of hilly and mountainous areas and promoting increase of agricultural benefits and farmers' income. Through typical survey,this paper made an objective evaluation of effect of agricultural comprehensive development of hilly and mountainous areas in Jiangsu Province from increasing farmers' income. Results indicated that agricultural comprehensive development investment projects in Jiangsu hilly and mountainous areas are closely coupled with local agricultural production structure; financial funds promote social capital input to construction of economic forest,fruit and grass planting,and livestock raising. Through demonstration and guidance of farmers,it promoted adjustment of agricultural production structure and increased farmers' income. Finally,it came up with pertinent policy recommendations. 展开更多
关键词 AGRICULTURAL comprehensive development increasing farmers’ INCOME EFFECT Jiangsu HILLY and mountainous areas
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Decreasing Arctic Sea Ice Mirrors Increasing CO_2 on Decadal Time Scale 被引量:3
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作者 Ola M Johannessen 《Atmospheric and Oceanic Science Letters》 2008年第1期51-56,共6页
Arctic sea ice is a keystone indicator of greenhouse-gas induced global climate change, which is expected to be amplified in the Arctic. Here we directly compare observed variations in arctic sea-ice extent and CO 2 s... Arctic sea ice is a keystone indicator of greenhouse-gas induced global climate change, which is expected to be amplified in the Arctic. Here we directly compare observed variations in arctic sea-ice extent and CO 2 since the beginning of the 20th century, identifying a strengthening linkage, such that in recent decades the rate of sea-ice decrease mirrors the increase in CO 2 , with r ~ -0.95 over the last four decades, thereby indicating that 90% (r 2 ~ 0.90) of the decreasing sea-ice extent is empirically "accounted for" by the increasing CO 2 in the atmosphere. The author presents an empirical relation between annual sea-ice extent and global atmospheric CO 2 concentrations, in which sea-ice reductions are linearly, inversely proportional to the magnitude of increase of CO 2 over the last few decades. This approximates sea-ice changes during the most recent four decades, with a proportionality constant of 0.030 million km 2 per ppmv CO 2 . When applied to future emission scenarios of the Intergovernmental Panel on Climate Change (IPCC), this relationship results in substantially faster ice decreases up to 2050 than predicted by IPCC models. However, departures from this projection may arise from non-linear feedback effects and/or temporary natural variations on interannual timescales, such as the record minimum of sea-ice extent observed in September 2007. 展开更多
关键词 CO2 increase ice decrease ice projection to2050
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Increasing physical activity among children and adolescents:Innovative ideas needed 被引量:1
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作者 Tom Baranowski 《Journal of Sport and Health Science》 SCIE 2019年第1期1-5,共5页
1.Introduction For anyone paying attention,this is a disruptive time in science in general and in health promotion science in particular.Obesity is the most prevalent nutrition-related health problem around the globe.... 1.Introduction For anyone paying attention,this is a disruptive time in science in general and in health promotion science in particular.Obesity is the most prevalent nutrition-related health problem around the globe.The issue of whether,as is commonly thought,obesity is causative of early mortality or whether it is only a marker of risk has been raised.The lack of substantial and maintained change in child obesity prevention has been recognized, and numerous limitations in our conceptual and methodological approach to obesity prevention have been identified. 展开更多
关键词 increasing PHYSICAL INTRODUCTION paying ATTENTION
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Water-use efficiency in response to simulated increasing precipitation in a temperate desert ecosystem of Xinjiang, China 被引量:6
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作者 HUANG Gang LI Yan +2 位作者 MU Xiaohan ZHAO Hongmei CAO Yanfeng 《Journal of Arid Land》 SCIE CSCD 2017年第6期823-836,共14页
Water-use efficiency(WUE) is a key plant functional trait that plays a central role in the global cycles of water and carbon. Although increasing precipitation may cause vegetation changes, few studies have explored... Water-use efficiency(WUE) is a key plant functional trait that plays a central role in the global cycles of water and carbon. Although increasing precipitation may cause vegetation changes, few studies have explored the linkage between alteration in vegetation and WUE. Here, we analyzed the responses of leaf WUE, ecosystem carbon and water exchanges, ecosystem WUE, and plant community composition changes under normal conditions and also under extra 15% or 30% increases in annual precipitation in a temperate desert ecosystem of Xinjiang, China. We found that leaf WUE and ecosystem WUE showed inconsistent responses to increasing precipitation. Leaf WUE consistently decreased as precipitation increased. By contrast, the responses of the ecosystem WUE to increasing precipitation are different in different precipitation regimes: increasing by 33.9% in the wet year(i.e., the normal precipitation years)and decreasing by 4.1% in the dry year when the precipitation was about 30% less than that in the wet year.We systematically assessed the herbaceous community dynamics, community composition, and vegetation coverage to explain the responses of ecosystem WUE, and found that the between-year discrepancy in ecosystem WUE was consistent with the extent to which plant biomass was stimulated by the increase in precipitation. Although there was no change in the relative significance of ephemerals in the plant community, its greater overall plant biomass drove an increased ecosystem WUE under the conditions of increasing precipitation in 2011. However, the slight increase in plant biomass exerted no significant effect on ecosystem WUE in 2012. Our findings suggest that an alteration in the dominant species in this plant community can induce a shift in the carbon-and water-based economics of desert ecosystems. 展开更多
关键词 desert ecosystem ecosystem water-use efficiency gross carbon exchange increasing precipitation leaf water-use efficiency net carbon exchange Gurbantunggut Desert
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Preparation and Characterization of Phenolic Prepolymer Impregnated Chinese Fir by Cyclic Increasing-Pressure Method with Green and Efficient 被引量:2
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作者 Yuan Zhang Ping Li +3 位作者 Yiqiang Wu Guangming Yuan Xianjun Li Yingfeng Zuo 《Journal of Renewable Materials》 SCIE EI 2020年第11期1473-1488,共16页
The Chinese fir wood was impregnated using a cyclic increasingpressure method(CIPM)with phenolic prepolymers as the impregnating modifier.Unmodified Chinese fir and progressive increasing-pressure method(PIPM)impregn... The Chinese fir wood was impregnated using a cyclic increasingpressure method(CIPM)with phenolic prepolymers as the impregnating modifier.Unmodified Chinese fir and progressive increasing-pressure method(PIPM)impregnated Chinese fir were used as reference samples and were compared and analyzed.The product’s chemical structure,internal morphology,crystal structure,and heat resistance were characterized.The transversal and longitudinal sections showed better filling effects,so that it bore greater external loading and reduced the water storage space.CIPM infused more phenolic prepolymer into the Chinese fir.Not only producing more physical filling but also forming more hydrogen bond associations and chemical bond combinations.Compared with PIPM and unmodi-fied Chinese fir,the CIPM impregnated Chinese fir had better mechanical strength and water resistance.The cellulose chains in CIPM impregnated Chinese fir were more closely linked and their crystallinity were clearly improved.Changes in internal morphology and crystal structure explained the reason why the mechanical properties and water resistance of CIPM impregnated Chinese fir were improved significantly.This Chinese fir had lower thermal decomposition rates,higher decomposition residual rates,and smaller combustion flames,which confirmed that it possessed improved heat and fire resistance. 展开更多
关键词 Chinese fir phenolic prepolymer cyclic increasing pressure method chemical structure crystalline structure heat resistance
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Effect of Increasing Speed on Stress of Biaxial Bogie Frames 被引量:1
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作者 Mohammad Zehsaz Farid Vakili Tahami +1 位作者 Ali Ziaei Asl Fatemeh Ahmadian 《Engineering(科研)》 2011年第3期276-284,共9页
Increasing the trains’ speed has always been one of the goals of any railway industry and train manufacturers. Also, the influence of the train speed on bogie’s dynamics has an immense importance. Therefore, it is i... Increasing the trains’ speed has always been one of the goals of any railway industry and train manufacturers. Also, the influence of the train speed on bogie’s dynamics has an immense importance. Therefore, it is important to analyze the effect of train speed on the stress distribution in different parts of train structure. In this study the result of the increasing speed on the applied stresses of a biaxial bogie frame has been examined. For this purpose, a biaxial bogie frame has been modeled using finite element analysis. Static and dynamic forces applied on the bogie with biaxial frame have been obtained for different speeds and rail roughness. The Von Mises stresses are adopted as equivalent stresses in the strength calculation. The results show that maximum stress always has been induced in the bogie bowl also the increase in bogie’s speed has remarkable effect on the increment of applied stresses in the bogie frame. 展开更多
关键词 BIAXIAL BOGIE Frame SPEED increase RAIL Way ROUGHNESS STRESS Finite Element Analysis
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C1q/TNF-related protein 1 promotes vasodilatory dysfunctions by increasing arginase 1 activity and uncoupling of endothelial nitric oxide synthase 被引量:1
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作者 Xiaoqun Wang Chang Li +4 位作者 Jiawei Chen Ying Shen RuiyanZhang Weifeng Shen Lin Lu 《中国循环杂志》 CSCD 北大核心 2018年第S01期131-131,共1页
Objective C1q/TNF-related protein(CTRP)1 was initiallyidentified as a paralog of adiponectin based on the similarity in C1q domain of these two proteins.Previously,we showed that CTRP1promotes the development of ather... Objective C1q/TNF-related protein(CTRP)1 was initiallyidentified as a paralog of adiponectin based on the similarity in C1q domain of these two proteins.Previously,we showed that CTRP1promotes the development of atherosclerosis by increasing endothelial adhesiveness.Here,we sought to investigate whether CTRP1 also influences vascular dilatory functions. 展开更多
关键词 C1q/TNF-related PROTEIN 1 increasing ARGINASE 1 ACTIVITY endothelial nitric oxide synthase
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