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Susceptible time window and endurable duration of cotton fiber development to high temperature stress
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作者 XU Bo ZHOU Zhi-guo +5 位作者 GUO Lin-tao XU Wen-zheng ZHAO Wen-qin CHEN Bing-lin MENG Ya-li WANG You-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第9期1936-1945,共10页
The development of the cotton fiber is very sensitive to temperature variation, and high temperature stress often causes reduced fiber yield and fiber quality. Short-term high temperature stress often occurs during co... The development of the cotton fiber is very sensitive to temperature variation, and high temperature stress often causes reduced fiber yield and fiber quality. Short-term high temperature stress often occurs during cotton production, but little is known about the specific timing and duration of stress that affects fiber development. To make this clear, pot experiments were carried in 2014 and 2015 in a climate chamber using cotton cultivars HY370WR(less sensitive variety) and Sumian 15(heat sensitive variety), which present different temperature sensitivities. Changes of the most important fiber quality indices(i.e., fiber length, fiber strength and marcironaire) and three very important fiber development components(i.e., cellulose, sucrose and callose) were analyzed to define the time window and critical duration to the high temperature stress at 34°C(max38°C/min30°C). When developing bolls were subjected to 5 days of high temperature stress at different days post-anthesis(DPA), the changes(Δ%) of fiber length, strength and micronire, as a function of imposed time followed square polynomial eq. as y=a+bx+cx^2, and the time around 15 DPA was the most sensitive period for fiber quality development in response to heat stress. When 15 DPA bolls were heat-stressed for different durations(2, 3, 4, 5, 6, 7 days), the changes(Δ%) of fiber length, strength and micronire, as a function of stress duration followed logistic equations y=A_1-A_2/1+(x/x_0)~p+A_2. Referred to that 5, 10 and 15% are usually used as criteria to decide whether techniques are effective or changes are significant in crop culture practice and reguard to the fiber quality indices change range, we suggested that 5% changes of the major fiber quality indices(fiber length, fiber strength and micronaire) and 10% changes of fiber development components(cellulose, sucrose and callose) could be taken as criteria to judge whether fiber development and fiber quality have been significantly affected by high temperature stress. The key time window for cotton fiber development in response to the high temperature stress was 13–19 DPA, and the critical duration was about 5 days. 展开更多
关键词 cotton(Gossypium hirsutum L.) fiber quality high temperature stress susceptible time window stress endurable duration
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A Study of the Time Narrative in Curious Case of Benjamin Button
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作者 柴晓丽 《海外英语》 2017年第3期167-169,共3页
This paper aims to provide new research perspective and highlight the importance of time in a novel.The paper first generally summarizes the research on the novel home and abroad.It goes on to describe the curious tim... This paper aims to provide new research perspective and highlight the importance of time in a novel.The paper first generally summarizes the research on the novel home and abroad.It goes on to describe the curious time in the novel and analyze the effect.Then,in light of Geneard Genette’s theory,the paper analyzes the time duration and the effects.It points out that the narration of time contributes to reinforcing the theme and the adjustment of the narrative rhythm. 展开更多
关键词 time narrative time narrative effect time duration
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Arctic summer sea ice phenology including ponding from 1982 to 2017
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作者 Xiaoli Chen Chunxia Zhou +3 位作者 Lei Zheng Mingci Li Yong Liu Tingting Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第9期169-181,共13页
Information on the Arctic sea ice climate indicators is crucial to business strategic planning and climate monitoring.Data on the evolvement of the Arctic sea ice and decadal trends of phenology factors during melt se... Information on the Arctic sea ice climate indicators is crucial to business strategic planning and climate monitoring.Data on the evolvement of the Arctic sea ice and decadal trends of phenology factors during melt season are necessary for climate prediction under global warming.Previous studies on Arctic sea ice phenology did not involve melt ponds that dramatically lower the ice surface albedo and tremendously affect the process of sea ice surface melt.Temporal means and trends of the Arctic sea ice phenology from 1982 to 2017 were examined based on satellite-derived sea ice concentration and albedo measurements.Moreover,the timing of ice ponding and two periods corresponding to it were newly proposed as key stages in the melt season.Therefore,four timings,i.e.,date of snow and ice surface melt onset(MO),date of pond onset(PO),date of sea ice opening(DOO),and date of sea ice retreat(DOR);and three durations,i.e.,melt pond formation period(MPFP,i.e.,MO–PO),melt pond extension period(MPEP,i.e.,PO–DOR),and seasonal loss of ice period(SLIP,i.e.,DOO–DOR),were used.PO ranged from late April in the peripheral seas to late June in the central Arctic Ocean in Bootstrap results,whereas the pan-Arctic was observed nearly 4 days later in NASA Team results.Significant negative trends were presented in the MPEP in the Hudson Bay,the Baffin Bay,the Greenland Sea,the Kara and Barents seas in both results,indicating that the Arctic sea ice undergoes a quick transition from ice to open water,thereby extending the melt season year to year.The high correlation coefficient between MO and PO,MPFP illustrated that MO predominates the process of pond formation. 展开更多
关键词 Arctic sea ice sea ice phenology melt timings and durations melt ponds remote sensing
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Reducing toxic effect of seed-soaked Cu fertilizer on germination of wheat
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作者 Sukhdev S. Malhi D. Leach 《Agricultural Sciences》 2012年第5期674-677,共4页
A laboratory incubation experiment (20℃) was conducted to find if the detrimental effects of seed-soaked Cu on wheat seedlings can be minimized by reducing time duration of seed in contact with Cu EDTA fertilizer sol... A laboratory incubation experiment (20℃) was conducted to find if the detrimental effects of seed-soaked Cu on wheat seedlings can be minimized by reducing time duration of seed in contact with Cu EDTA fertilizer solution. The 24 treatments in a 6 x 4 factorial arrangement included 6 rates/amounts of Cu (0, 15, 30, 60, 120 and 240 g Cu 100 kg-1 seed) and 4 seed-soaking time durations (0, 4, 8 and 16 h). The germination of wheat seed was 100% in the zero-Cu control treatments, irrespective of the duration of seed soaking time. However, seed germination decreased with increasing amount of fertilizer Cu in the seed-soaking solution, and the magnitude of reduction in seed germination due to Cu toxicity increased with increasing duration of seed-soaking time in the Cu fertilizer solution. For the seed-soaked treatments, the detrimental effect of Cu on germination was greatest with 16 h soaking, where only 13% - 18% of the seeds germinated with Cu applied at 15 to 30 g Cu 100 kg-1 seed. For the 4 and 8 h seed soaking treatments, germination of wheat seed ranged from 73% to 83% with 15 g Cu 100 kg-1 seed treatment and 42% to 62% with 30 g Cu 100 kg-1 seed. The findings suggest that the detrimental effect of Cu on germination of wheat seed soaked in Cu EDTA solution can be decreased by reducing duration of soaking time from 16 h to 4 or 8 h, but this needs further investigation using soil under growth chamber and/or field conditions in order to make valid recommendations for use of this new technology on a commercial scale. 展开更多
关键词 Amount/rate of CU Seed-Soaked CU SOAKING time/duration Solution CU
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An investigation of the persistence property of wind power time series 被引量:5
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作者 SUN HaiShun LI JiaMing +4 位作者 LI JingHua Wu Tong WEN JinYu XIE HaiLian YUE ChengYan 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第8期1578-1587,共10页
Mining the inherent persistence property of the time series of wind power is crucial for forecasting and controlling wind power.Few common methods exist that can fully depict and quantify the persistence property.Base... Mining the inherent persistence property of the time series of wind power is crucial for forecasting and controlling wind power.Few common methods exist that can fully depict and quantify the persistence property.Based on the definition of the active power output state of a wind farm,this paper describes the statistical persistence property of the duration time and state transition.Based on the results of our analysis of significant amounts of wind power field measurements,it is found that the duration time of wind power conforms to an inverse Gaussian distribution.Additionally,the state transition matrix of wind power is discovered to yield a ridge property,the gradient of which is related to the time scale of interest.A systemaic methodology is proposed accordingly,allowing the statistical characteristics of the wind power series to be represented appropriately. 展开更多
关键词 characteristics analysis persistence property duration time state transition wind power series
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Effects of timing and duration under brackish water mulch drip irrigation on cotton yield in northern Xinjiang,China 被引量:1
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作者 Wang Chunxia Yang Guang +3 位作者 Li Junfeng He Xinlin Xue Lianqing Long Aihua 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2017年第6期115-122,共8页
The brackish water is an important potential water source and has frequently been utilized to drip-irrigate cotton due to the water shortage in the arid region of Xinjiang,northwestern of China.The brackish water is u... The brackish water is an important potential water source and has frequently been utilized to drip-irrigate cotton due to the water shortage in the arid region of Xinjiang,northwestern of China.The brackish water is usually saline water with salinity ranging from 1 g/L to 5 g/L,which is widely distributed in this area,so the reasonable use of that brackish water may not only play a vital role in the local agricultural production,but also save plenty of freshwater.However,irrigation with brackish water usually causes the reduction of crop yield and soil salinization which can negatively impact plants through three major components:osmotic,nutritious and toxic stresses.Therefore,a field experiment,with eight different time-series irrigation modes using brackish water(3.5±0.2)g/L and freshwater(<1 g/L),beneath a combined film and drip-irrigation system was carried out to study the changes of soil salt content and cotton yield aiming to search for a balanced method during the 2 cotton growing seasons in 2012 and 2013.The results indicated that the time-series irrigation modes determined the soil salinity and moisture distribution based on observed spatio-temporal distribution of water content and electric conductivity,and soil salinity generally gathered at the depth of 0-10 cm and 60 cm of soil with the increase of irrigation quota.Moreover,the results demonstrated that the yields of cotton which was grown using brackish water and freshwater were better than those only using freshwater and the soil salinity with reasonable irrigation timing was not accumulated obviously. 展开更多
关键词 brackish water mulch drip irrigation timing and duration for irrigation irrigation scheduling COTTON
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The Temporal-Spatial Distribution of Light Intensity in Maize and Soybean Intercropping Systems 被引量:9
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作者 何汉明 杨磊 +5 位作者 赵丽华 吴晗 范黎明 谢勇 朱有勇 李成云 《Journal of Resources and Ecology》 CSCD 2012年第2期169-173,共5页
Intercropping can improve field microclimates, decrease the incidence of crop diseases, and increase crop yields, but the reasons for this remain unknown. Solar radiation is the most important environmental influence.... Intercropping can improve field microclimates, decrease the incidence of crop diseases, and increase crop yields, but the reasons for this remain unknown. Solar radiation is the most important environmental influence. To understand the mechanisms of intercropping we established an experiment consisting of three cropping patterns: a monocropping control {treatment A) and two intercropping treatments (B: two rows of maize and two rows of soybean intercropping; C: two rows of maize and four rows of soybean intercropping). Results show that compared to monocropping, intercropping increased the amount of light penetrating to inferior leaves in maize plants. Light intensity reaching maize plants at the heading stage in intercropping increased over two-fold at 30 cm above ground and 10-fold at 70 cm above ground, compared with monocropping. At the flowering to maturity stage, light intensity at 110, 160 and 210 cm above ground among maize plants was greatly increased in intercropping compared with monocropping, by some five-fold, two-fold and 12%, respectively. Moreover, light intensity declined more slowly at the measured heights in the intercropping system compared with monocropping. From the 7-18th leaf, light intensity per leaf increased two-fold in intercropping compared with monocropping. Daily light duration increased more than a mean of 5 h per day per leaf in intercropping compared with monocropping. The biological characters of maize including thousand kernel weight, yield per plant and area of ear leaves were all greater in intercropping than monocropping. These results suggest that, for maize, intercropping improves light density and duration significantly and this may contribute to biomass and yield increases. 展开更多
关键词 INTERCROPPING maize plants light intensity duration time biological characters
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Analysis of shopping behavior characteristics in the Keihanshin metropolitan area in Japan based on a person trip survey 被引量:2
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作者 Takashi Yamada Takumi Hayashida 《Geo-Spatial Information Science》 SCIE CSCD 2020年第4期305-315,共11页
This study analyzed weekday shopping behavior from a home base to a destination using data from the 4th Keihanshin metropolitan area person trip survey.We first analyzed the relationships between occupation and transp... This study analyzed weekday shopping behavior from a home base to a destination using data from the 4th Keihanshin metropolitan area person trip survey.We first analyzed the relationships between occupation and transportation means,transportation means and travel time,and transportation means and duration of time at the destination.Results of a chi-square test,residual analysis,and correspondence analysis confirmed that employed persons tend to travel by cars while unemployed persons tend to travel by bus or walk.The relationship between travel time and duration of time at the destination was also revealed according to transportation means.Results of a cluster analysis then classified shopping behaviors to expose four patterns.Finally,multiple regression analyzed the degree to which certain variables were related to duration of time at the destination.Results confirmed a strong relationship between duration of time at the destination and travel time.The degree of this factor’s influence on other variables was also clarified.The value of these findings is that the relationship between travel time by means of transportation and the duration of time at the destination was clarified using statistical analysis.We then found a highly accurate equation that estimates the duration of time at a destination from the travel time.If the duration of time at a destination can be estimated,it may be possible to more accurately develop the structure of rest facilities,the number of parking lots,the degree of congestion,and so on,which can be associated with the customer’s usage behavior in a shopping site.This research in this paper contributes to the field of urban analysis and marketing by presenting a new effective method for person trip survey and analysis. 展开更多
关键词 Person trip survey shopping behavior transportation means travel time duration of time at a destination
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Mobility Pattern of Taxi Passengers at Intra-Urban Scale:Empirical Study of Three Cities
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作者 Mengqiao XU Ling ZHANG +1 位作者 Wen LI Haoxiang XIA 《Journal of Systems Science and Information》 CSCD 2017年第6期537-555,共19页
The study of human mobility patterns is of both theoretical and practical values in many aspects. For long-distance travel, a few research endeavors have shown that the displacements of human travels follow a power-la... The study of human mobility patterns is of both theoretical and practical values in many aspects. For long-distance travel, a few research endeavors have shown that the displacements of human travels follow a power-law distribution. However, controversies remain regarding the issue of the scaling laws of human mobility in intra-urban areas. In this work, we focus on the mobility pattern of taxi passengers by examining five datasets of three metropolitans. Through statistical analysis, we find that the lognormal distribution with a power-law tail can best approximate both the displacement and the duration time of taxi trips in all the examined cities. The universality of the scaling laws of human mobility is subsequently discussed, in view of the analysis of the data. The consistency of the statistical properties of the selected datasets that cover different cities and study periods suggests that, the identified pattern of taxi-based intra-urban travels seems to be ubiquitous over cities and time periods. 展开更多
关键词 human mobility pattern taxi travel displacements duration time
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