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Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem
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作者 HAO Aihua LUO Zhengming CHEN Xiaojiang 《Journal of Mountain Science》 SCIE CSCD 2024年第1期146-159,共14页
Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradient... Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(P<0.05), and the percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(P<0.01) and Shannon-Weiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatment(P<0.05). The warmed aboveground biomass had a significant nonlinear response to soil temperature and significant linear responses to soil moisture(P<0.05). This study provided evidence that altitude is a factor in sensitivity to climate warming, and these different parameters(e.g., plant species richness, Shannon-Weiner index, soil temperature, soil moisture, SOC, and TN) can be used to measure this sensitivity. 展开更多
关键词 Warming effect Plant diversity pattern Community structure change Elevation gradient Alpine meadow ecosystem Mount Wutai
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Effects of Six Cultivation Patterns on Occurrence of Major Diseases and Pests and Yield of Rice 被引量:1
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作者 张舒 吕亮 +3 位作者 常向前 程建平 余永志 钟爱荣 《Agricultural Science & Technology》 CAS 2016年第3期700-707,共8页
The occurrence rules of major diseases and pests in rice were investigated under six cultivation patterns, i.e., mechanical plowing-artificial transplanting, mechanical plowing-mechanical transplanting, mechanical plo... The occurrence rules of major diseases and pests in rice were investigated under six cultivation patterns, i.e., mechanical plowing-artificial transplanting, mechanical plowing-mechanical transplanting, mechanical plowing-scattered transplanting,cattle plowing-artificial transplanting, cattle plowing-mechanical transplanting and cattle plowing-scattered transplanting. The results showed that the six cultivation patterns showed small effects on the occurrence of rice sheath blight, second-generation rice planthopper, rice stem borer and rice false smut, but showed great effects on the occurrence of rice leaf folder, third-and fourth-generation rice planthopper and weeds; there were certain differences in the rice yield among different cultivation patterns, and the rice yield under the pattern of mechanical plowing-mechanical transplanting ranked first, while that under the pattern of cattle plowing-scattered transplanting ranked last. 展开更多
关键词 Cultivation pattern RICE Disease peST WEED effect
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Long-term effects of pattern scan laser pan-retinal photocoagulation on diabetic retinopathy in Chinese patients: a retrospective study 被引量:7
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作者 Chuang-Xin Huang Kun-Bei Lai +6 位作者 Li-Jun Zhou Zhen Tian Xiao-Jing Zhong Fa-Bao Xu Ya-Jun Gong Lin Lu Chen-Jin Jin 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第2期239-245,共7页
●AIM:To evaluate the long-term effects of pattern scan laser(PASCAL)pan-retinal photocoagulation(PRP)on diabetic retinopathy(DR)in Chinese patients.●METHODS:In this retrospective study,we evaluated clinical data of ... ●AIM:To evaluate the long-term effects of pattern scan laser(PASCAL)pan-retinal photocoagulation(PRP)on diabetic retinopathy(DR)in Chinese patients.●METHODS:In this retrospective study,we evaluated clinical data of 29 patients(53 eyes)with severe non-proliferative DR(SNPDR)or proliferative DR(PDR)who received PRP and follow-up at our hospital from 2008 to 2013.Sixteen patients(29 eyes)received PASCAL PRP and 13 patients(24 eyes)received 100-ms conventional laser PRP.●RESULTS:After long-term follow-up(mean,min-max days:719.8,290-1666 for PASCAL PRP vs 743.5,240-1348 for conventional PRP,P=0.569),patients receiving PASCAL PRP required fewer photocoagulation sessions than the conventional PRP group(2.6±1.0 vs 3.9±0.9,P<0.01).Best corrected visual acuity(BCVA)was reduced slightly in PASCAL PRP group while reduced significantly in conventional PRP group.At last visit,24 eyes in the PASCAL group(88.9%)and 21 eyes in the conventional group(91.7%)were improved or stable.Two eyes in PASCAL PRP group(7.4%)and 3 eyes in the conventional PRP group(12.5%)developed vitreous hemorrhage or vitreous fibrovascular proliferation.●CONCLUSION:PASCAL PRP is as effective and may be more conducive to maintaining visual acuity with less treatment sessions for DR treatment compared to conventional laser PRP. 展开更多
关键词 PROLIFERATIVE DIABETIC RETINOPATHY severe non-proliferative DIABETIC RETINOPATHY pattern SCAN laser pan-retinal photocoagulation clinical effect
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Tunable acoustic radiation pattern assisted by effective impedance boundary 被引量:1
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作者 钱枫 全力 +2 位作者 王力维 刘晓宙 龚秀芬 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期215-220,共6页
The acoustic wave propagation from a two-dimensional subwavelength slit surrounded by metal plates decorated with Helmholtz resonators (HRs) is investigated both numerically and experimentally in this work. Owing to... The acoustic wave propagation from a two-dimensional subwavelength slit surrounded by metal plates decorated with Helmholtz resonators (HRs) is investigated both numerically and experimentally in this work. Owing to the presence of HRs, the effective impedance of metal surface boundary can be manipulated. By optimizing the distribution of HRs, the asymmetric effective impedance boundary will be obtained, which contributes to generating tunable acoustic radiation pattern such as directional acoustic beaming. These dipole-like radiation patterns have high radiation efficiency, no finger- print of sidelobes, and a wide tunable range of the radiation pattern directivity angle which can be steered by the spatial displacements of HRs. 展开更多
关键词 effective impedance boundary acoustic radiation pattern Helmholtz resonator
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Pattern Structure of Deterministic Displacement in Random Porous Media with Dispersion Effect
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作者 TIANJu-Ping YAOKai-Lun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第1期91-95,共5页
A new model — model of random porous media degradation via several fluid displacing, freezing, and thawing cycles is introduced and investigated in this paper. The fluid transport is based on the deterministic method... A new model — model of random porous media degradation via several fluid displacing, freezing, and thawing cycles is introduced and investigated in this paper. The fluid transport is based on the deterministic method with dispersion effect. The result shows that the topology and the geometry of the porous media have a strong effect on displacement processes. The cluster size of viscous fingering (VF) pattern in percolation cluster increases with the increase of iteration parameter n. When iteration parameter , VF pattern does not change with n. We find that the displacement fluid forms trapping regions in random porous media with dispersion effect. And the trapping regions will expand with the increasing of the iteration parameter n. When r (throat size) and , the peak value of the distribution increases as n increases, where is the normalized distribution of throat sizes after different displacement-damages but before freezing. The peak value of the distribution reaches a maximum when and , where is the normalized distribution of the size of invaded throat. This result is different from invasion percolation. It is found that the sweep efficiency E increases along with the increasing of iteration parameter n and decreases with the network size L, and E has a minimum as L increases to the maximum size of lattice. The VF pattern in percolation cluster has one frozen zone and one active zone. 展开更多
关键词 random porous media dispersion effect pattern structure
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Pattern-Prototype Effects of Processing Familiar Metonymy in Sentential Context
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作者 LI Jie 《Journal of Literature and Art Studies》 2021年第6期404-411,共8页
This study conducted an eye-tracking experiment on processing different patterns of Chinese familiar metonymy in sentential contexts.It analyzes five eye-tracking measures concerning the processing of metonymy.The res... This study conducted an eye-tracking experiment on processing different patterns of Chinese familiar metonymy in sentential contexts.It analyzes five eye-tracking measures concerning the processing of metonymy.The results indicate that different patterns of metonymy experience different processing processes under a sentential-context condition,and results in prototype effects.The main finding is that Spatial Part&Whole metonymy is more prototypical than other three patterns of metonymy,i.e.,Container and Contained,Location and Located,Entity and Adjacent Entity,and that the effect of metonymy pattern on the processing is stable and observable.It concludes that contextual information facilitates the processing of non-prototypical metonymy,but restrain the processing of prototypical metonymy. 展开更多
关键词 EYE-TRACKING pattern effects familiar metonymy PROCESSING sentential contexts
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Behaviour of layered sandstone under Brazilian test conditions:Layer orientation and shape effects 被引量:9
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作者 Abbass Tavallali André Vervoort 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2013年第5期366-377,共12页
The experimental study in this paper focuses on the effects of the layer orientation and sample shape on failure strength and fracture pattern of samples tested under Brazilian test conditions(i.e.diametrical loading ... The experimental study in this paper focuses on the effects of the layer orientation and sample shape on failure strength and fracture pattern of samples tested under Brazilian test conditions(i.e.diametrical loading of cylindrical discs)for one particular layered sandstone which is from Modave in the south of Belgium.The variations of the strength in combination with the failure patterns are examined as a function of the inclination angle between the layer plane and the loading direction.The experimental,results clearly show that the induced fracture patterns are a combination of tensile and/or shear fractures.In shape effect experiments the layer thickness and the number of layer boundaries are investigated.Different blocks of Modave sandstone are used to prepare samples.The layer thickness is different among the various blocks,but the layer thickness in each studied rock block can be considered to be constant;hence,the number of layer boundaries changes according to the sample diameter for samples of the same block.The experimental study shows that the layer thickness plays a more important role than the number of layer boundaries per sample. 展开更多
关键词 Layered sandstone Brazilian test Fracture pattern Layer activation Shape effect
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Effect of spatial pattern on nutrient reduction in the Liaohe Delta 被引量:2
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作者 LI Xiu-zhen, XIAO Du-ning, HU Yuan-man, WANG Xian-li (Institute of Applied Ecology, CAS, Shenyang 110016, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期336-349,共14页
The effect of spatial pattern on the nutrient reduction is investigated based on the spatial simulation model developed for the study area of the Liaohe Delta, China. Four scenarios are designed to test the effect of ... The effect of spatial pattern on the nutrient reduction is investigated based on the spatial simulation model developed for the study area of the Liaohe Delta, China. Four scenarios are designed to test the effect of different landscape components on the nutrient reduction in the reed marsh: Canal density, reed area size, reed area shrinking pattern, and pumping station position. Based on a spatial model designed for the study area, the nutrient reduction in each case of these scenarios is simulated. The results indicate that each factor brings less than 10% change in the total nutrient reduction rate. More canals will not help much to improve nutrient reduction. Smaller areas are more efficient than larger ones. The shrinkage pattern is better than others in keeping a higher nutrient reduction rate. It is also more efficient to keep the pumping station near the border of the area to be irrigated. These conclusions provide theoretical supports to strategy makers for local land use planning, and contribute to the understanding of the relationship between landscape patterns and functions. 展开更多
关键词 pattern effect nutrient reduction WETLAND canal density area size shrinking pattern pumping station position
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Spatial pattern of paulownia witches' broom and its effects on the growth of Paulownia elongata in Shaanxi Province,China 被引量:4
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作者 LI Jin ZHANG Xing-yao TIAN Cheng-ming 《Forestry Studies in China》 CAS 2009年第1期34-38,共5页
The spatial pattern of paulownia witches' broom was investigated using an Iwao's (m^*-m) model in Shaanxi Province, China. Iwao's (m^*-m) model revealed that spatial pattern of paulownia witches' broom exhib... The spatial pattern of paulownia witches' broom was investigated using an Iwao's (m^*-m) model in Shaanxi Province, China. Iwao's (m^*-m) model revealed that spatial pattern of paulownia witches' broom exhibited a uniform distribution in sample plots. In this model, characteristics of contagiousness coefficient (a) justified the probability of infection by virus-transmission vectors. For tree age less than six, susceptible individuals were aggregated as clusters in the plots and then mutually repelled over age. A preliminary survey of stand volume show that from age five to six, stand volumes of disease grade II showed excessive vegetative growth and returned to normal level between ages ten and 11. Loss rate of volume increment with disease grade II decreased, and then returned to raising trend both at grades III and IV. This phenomenon is possibly caused by an over-compensation effect and by environmental factors. The redundancy of growth hormones in branches, shoots, leaves, buds and roots increased the stem volume of entire trees. 展开更多
关键词 paulownia witches' broom spatial pattern stand volume loss rate of volume increment over-compensation effect
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Influence of Different Quality Sperm on Early Embryo Morphokinetic Parameters and Cleavage Patterns:A Retrospective Time-lapse Study 被引量:2
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作者 Qiu-yue LIAO Bo HUANG +4 位作者 Si-jia ZHANG Jing CHEN Ge CHEN Ke-zhen LI Ji-hui AI 《Current Medical Science》 SCIE CAS 2020年第5期960-967,共8页
To investigate whether sperm with low concentration and motility can impact preimplantation embryos and to analyze how the effects present under a time-lapse incubation system,2905 oocytes were collected from 219 coup... To investigate whether sperm with low concentration and motility can impact preimplantation embryos and to analyze how the effects present under a time-lapse incubation system,2905 oocytes were collected from 219 couples between January 2014 and December 2015.Patients were divided into three groups according to sperm quality.Morphokinetic parameters and six cleavage patterns in the initial three cleavages were evaluated using the Primo Vision system.Embryo quality and clinic outcomes such as implantation rate,pregnancy rate and live birth rate were measured.The results showed that the concentration and motility of sperm correlated strongly with the rate of 2PN embryos,good-quality embryos on D3,blastocysts on D5/6 and good quality embryos on D5/6.The time-lapse system recordings showed that compromised sperm quality could result in a significant delay in cc l and a decrease in cc2,and impact embryo developmental potential mainly through large fragments or/and blastomere fragmentation in the initial three cleavages.In conclusion,sperm with low concentration and motility can have paternal effects on preimplantation embryos.These paternal effects present both as changes in morphokinetic parameters and cleavage patterns,which occur as early as fertilization and may cause severe damage to the preimplantation embryos. 展开更多
关键词 embryo development patermal effect TIME-LAPSE morphokinetic parameters cleavage patterns
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Study on cumulative effects of different cultivation patterns on wetland soil environment
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作者 YUAN Zhaohua JIANG Ming +1 位作者 SONG Ge ZHOU Jia 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第3期229-234,共6页
Cumulative effects on wetland soils under different cultivation patterns were analyzed in the experimental fields of the Ecological Experimental Station of Mire-wetlands in Sanjiang Plain. The results suggested that t... Cumulative effects on wetland soils under different cultivation patterns were analyzed in the experimental fields of the Ecological Experimental Station of Mire-wetlands in Sanjiang Plain. The results suggested that the paddy field combined with the glebe to act on the soil environment. Under the combination of natural and anthropological factors, the cultivation of the paddy field and the glebe obviously related with different kinds of fertility factors of soil. The remarkable relation among organic matter, total nitrogen and available nitrogen reflected the fertilization of the soil at some extent. 展开更多
关键词 Sanjiang Plain WETLAND cultivation pattern accumulative effects
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Influencing Factors and Urbanization Effects of the Spatial Pattern of Floating Population in Anhui Province
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作者 XU Zeguo 《Journal of Landscape Research》 2019年第5期88-94,98,共8页
Based on the population census data,this paper analyzed the influencing factors and urbanization effects of the floating population in Anhui Province using ArcGIS spatial analysis,factor analysis,multiple liner regres... Based on the population census data,this paper analyzed the influencing factors and urbanization effects of the floating population in Anhui Province using ArcGIS spatial analysis,factor analysis,multiple liner regression,and spatial autocorrelation,and reached the following conclusions:① From 2000 to 2010,the floating population in Anhui Province was concentrated in cities dotted the Huai River and the Yangtze River,and Hefei City absorbed the most inter-provincial floating population and intra-provincial floating population.② The overall economic strength had the greatest impact on attracting floating population,while the income level factor has less impact on attracting floating population.The overall economic strength and the strength of science,education,culture,and health of prefecture-level cities in Anhui Province were more attractive to the intra-provincial floating population and less attractive to the inter-provincial floating population.③ Population mobility promoted urbanization.Large cities could attract more migrants from counties.The urban population system in Anhui Province was generally developing towards the concentration of large cities,while the proportion of the county population in the total population was decreased. 展开更多
关键词 FLOATING POPULATION Spatial pattern Influencing FACTOR URBANIZATION effect
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Evaluation of the migration and environmental effects of metal elements within cementitious gangue-fly ash backfill in underground coal mines
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作者 Xuejie Deng Yuan Jiao +5 位作者 Shicong Li Nan Zhou Yan An Erol Yilmaz Qingxue Zheng Xifeng Liang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第11期1551-1562,共12页
Cementitious gangue-fly ash backfill(CGB)is used as a green mining technology worldwide.However,under the coupled effects of geological stress and groundwater,the metal elements in the CGB tend to migrate into nearby ... Cementitious gangue-fly ash backfill(CGB)is used as a green mining technology worldwide.However,under the coupled effects of geological stress and groundwater,the metal elements in the CGB tend to migrate into nearby strata,which can consequently result in pollution of the groundwater environment.In this paper,the influence of initial pH and stress damage on the migration behavior of metal elements in CGB is quantitatively studied through the multi-physical field coupling model of stress-permeability-con centration.The enhanced Nemerow index evaluation method is used to comprehensively evaluate the impact of these metal elements migration behaviors on the groundwater environment.The research results show that:(1)When the stress damage of the CGB increases from 0.76 to 0.95,the Darcy velocity at the bottom of the CGB first increases,then decreases,and finally stabilizes at 2.01×10^(-7)m/s.The longest time to reach the maximum Darcy velocity is 3 a.(2)When the damage of the CGB is 0.95,the farthest migration distances of Al,Cr,Mn,Fe,Ba,and Pb are 40.5,34.0,29.8,32.9,38.8 and 32.1 m,respectively.(3)The alkaline environment stimulates the migration of Al,Cr,Fe,Mn,and Pb,whereas Ba migrates farther under acidic conditions.The farthest migration distance of Ba is 31.6 m under pH 3.(4)The enhanced Nemerow index indicates that when stress damage increases from 0.76 to 0.95,the areas with poor water quality increase from 0 to 1.71%,and no area is classified as very poor grade.When the initial pH changes from 3 to 11,100%of the region is classified as fair or above.The initial pH of the CGB has a relatively slight influence on the groundwater environment.This study provides experimental data and theoretical basis for the environmental evaluation of CGB. 展开更多
关键词 Cementitious gangue-fly ash backfill Metal elements Migration patterns Environmental effects Geological stress damage pH
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钢-PE混杂纤维水泥基复合材料动态压缩性能试验研究
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作者 李堂军 李亮 +1 位作者 王子晨 姜锡权 《防灾减灾工程学报》 CSCD 北大核心 2024年第5期1140-1148,共9页
将钢纤维和PE纤维混杂掺入水泥基基体材料中,控制纤维体积总掺量为2%,通过改变两种纤维比例,制成E2、E1.5S0.5、E1S1、E0.5S1.5和S2试件,应用分离式霍普金森压杆(Split Hopkinson Pressure Bar, SHPB)装置,开展了钢-PE混杂纤维水泥基复... 将钢纤维和PE纤维混杂掺入水泥基基体材料中,控制纤维体积总掺量为2%,通过改变两种纤维比例,制成E2、E1.5S0.5、E1S1、E0.5S1.5和S2试件,应用分离式霍普金森压杆(Split Hopkinson Pressure Bar, SHPB)装置,开展了钢-PE混杂纤维水泥基复合材料在高应变率(30~120 s^(-1))条件下的动态压缩试验,从试件破坏形态、材料的动态抗压强度、韧性及其应变率效应等方面进行了分析研究。试验结果表明:①钢-PE混杂纤维水泥基复合材料表现出明显的应变率效应,其动态抗压强度、韧性以及动态抗压强度增长因子(Dynamic Increase Factor of Compressive Strength, DIF)随着应变率的增加而提高。应变率为60-80 s^(-1)时,PE纤维增韧效果更好;而应变率为100s^(-1)时,钢纤维增韧效果更优。②随着PE纤维掺量的增加,材料应力-应变曲线的应变硬化现象更明显。而钢纤维掺量达到1.5%以上且继续增大时,材料的动态抗压强度和韧性得到提高,表明一定掺量的钢纤维可以提高材料动态抗压强度的应变率敏感性。③两种纤维混杂的试件其动态压缩力学性能要优于单掺PE或钢纤维的试件,综合动态抗压强度、韧性以及DIF,得出抵抗冲击压缩荷载的最优纤维配比是0.5%的PE纤维+1.5%的钢纤维。 展开更多
关键词 钢-pe混杂纤维 动态压缩 动态抗压强度增强因子 应变率效应 分离式霍普金森压杆
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The effect of different irrigation patterns on rice yield and water consumption
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作者 CHEN Guolin and WANG Renmin, Agro Dept, Zhejiang Agri Univ, Hangzhou 310029, China 《Chinese Rice Research Newsletter》 1998年第1期11-12,共2页
The ecological and physiological water require-ment of rice and rice yield was studied underthree irrigation patterns, which were A: moistirrigation, remains 70-90% of saturated soilwater content except 3-4 cm deep wa... The ecological and physiological water require-ment of rice and rice yield was studied underthree irrigation patterns, which were A: moistirrigation, remains 70-90% of saturated soilwater content except 3-4 cm deep water layerin tillering stage in paddy; B: flood irrigation,remains 4-5 cm deep water layer except 80%relative water content in the late tillering stage 展开更多
关键词 BE The effect of different irrigation patterns on rice yield and water consumption
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The Aharonov-Bohm Effect: An Exploration of Quantum Interference and Electromagnetic Potentials
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作者 Bahman Zohuri 《Journal of Energy and Power Engineering》 CAS 2024年第3期79-87,共9页
The AB(Aharonov-Bohm)effect is a pivotal quantum mechanical phenomenon that illustrates the fundamental role of the electromagnetic vector potential A in determining the phase of a charged particle’s wave function,ev... The AB(Aharonov-Bohm)effect is a pivotal quantum mechanical phenomenon that illustrates the fundamental role of the electromagnetic vector potential A in determining the phase of a charged particle’s wave function,even in regions where the magnetic field B is zero.This effect demonstrates that quantum particles are influenced not only by the fields directly present but also by the potentials associated with those fields.In the AB effect,an electron beam is split into two paths,with one path encircling a solenoid and the other bypassing it.Despite the absence of a magnetic field in the regions traversed by the beams,the vector potential A associated with the magnetic flux Φ through the solenoid induces a phase shift in the electron’s wave function.This phase shift,quantified by △φ=qΦ/hc,manifests as a change in the interference pattern observed in the detection screen.The phenomenon underscores the principle of gauge invariance in QED(quantum electrodynamics),where physical observables remain invariant under local gauge transformations of the vector and scalar potentials.This reinforces the notion that the vector potential A has a profound impact on quantum systems,beyond its classical role.This article outlines the AB effect,including its theoretical framework,experimental observations,and implications.The focus on the role of the vector potential in quantum mechanics provides a comprehensive understanding of this important phenomenon. 展开更多
关键词 AB effect vector potential(A) magnetic flux(Φ) quantum phase shift gauge invariance electromagnetic potentials interference pattern scalar fields longitudinal waves QED
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不同厚度PE膜包装对鲜食石榴籽粒保鲜效果的影响 被引量:9
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作者 初丽君 王琼 +1 位作者 王敏 寇莉萍 《保鲜与加工》 CAS 北大核心 2017年第6期20-26,共7页
以陕西临潼"净皮甜"鲜食石榴籽粒为试材,采用不同厚度(0.02、0.03、0.04、0.05 mm)PE保鲜膜对石榴籽粒进行包装,在(4±1)℃条件下贮藏,定期对包装袋内气体含量、可溶性固形物含量、色泽、DPPH自由基清除能力、总酚、花色... 以陕西临潼"净皮甜"鲜食石榴籽粒为试材,采用不同厚度(0.02、0.03、0.04、0.05 mm)PE保鲜膜对石榴籽粒进行包装,在(4±1)℃条件下贮藏,定期对包装袋内气体含量、可溶性固形物含量、色泽、DPPH自由基清除能力、总酚、花色苷、细胞膜透性进行测定,研究不同厚度PE膜对石榴籽粒保鲜效果及感官品质评价的影响。结果表明,不同厚度的包装膜对石榴籽粒的颜色及花色苷的含量无显著影响,但随着厚度的增加,呼吸作用明显受到抑制,并可较好地保持可溶性固形物含量及总酚含量,提高DPPH自由基清除能力,抑制相对电导率的增加,保持较好的感官品质。其中,0.05 mm厚的PE包装袋对石榴籽粒的保鲜效果最佳。 展开更多
关键词 鲜食 石榴籽粒 不同厚度 保鲜效果 聚乙烯膜
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微胶囊红磷对PE/Ca(OH)2复合材料动态流变行为的影响 被引量:4
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作者 杨浩 黄宝铨 +4 位作者 杨燕 陈艺兰 刘欣萍 肖荔人 陈庆华 《塑料》 CAS CSCD 北大核心 2008年第6期61-63,108,共4页
采用AR-2000旋转流变仪对不同含量微胶囊红磷(MRP)协效阻燃的PE/Ca(OH)2复合材料进行流变性能分析。探讨了MRP的用量对PE/Ca(OH)2/MRP复合材料的动态流变行为、力学性能和阻燃性能之间关系的影响。结果发现:当MRP含量为6份时能够较好地... 采用AR-2000旋转流变仪对不同含量微胶囊红磷(MRP)协效阻燃的PE/Ca(OH)2复合材料进行流变性能分析。探讨了MRP的用量对PE/Ca(OH)2/MRP复合材料的动态流变行为、力学性能和阻燃性能之间关系的影响。结果发现:当MRP含量为6份时能够较好地满足PE/Ca(OH)2/MRP复合材料的加工性能、力学性能以及阻燃性能。 展开更多
关键词 微胶囊红磷 聚乙烯 动态流变 第二平台 PAYNE效应
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光敏不育粳稻及其杂交后代的光周期效应指数(PE)分析 被引量:4
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作者 薛光行 陈长利 陈平 《作物学报》 CAS CSCD 北大核心 1996年第3期271-278,共8页
作者通过剥蘖分株,把供试水稻每一单株的4个第1次分蘖分别栽培在高温长日(光照时数/平均气温为15小时/28.4℃)、低温长日(15小时/23.5℃)、高温短日(10小时/28.4℃)和低温短日(10小时/23.5℃)环境下,在对号统计供试个体分株苗的育性(花... 作者通过剥蘖分株,把供试水稻每一单株的4个第1次分蘖分别栽培在高温长日(光照时数/平均气温为15小时/28.4℃)、低温长日(15小时/23.5℃)、高温短日(10小时/28.4℃)和低温短日(10小时/23.5℃)环境下,在对号统计供试个体分株苗的育性(花粉败育度和小穗不育率)、计算个体光周期效应指数(PE,等于长日与短日植株育性之差)的基础上,分析了光敏不育粳稻(农垦58s、7001s)及它们的杂交F_1、BF_1和F_2个体、群体的PE.结果表明:1.农垦58s和7001s群体的PE以花粉败育度(或小穗不育率)为指标时大于50%(或 6.4%).温度处理间差异不显著.2.F_1群体的PE表现超亲优势.3.BF_1和F_2个体的PE(A)或PE(B)(分别表示以花粉败育度或小穗不育率为指标的PE)的变异远大于双亲.PE(A)的遗传力估值为82.0%(高温环境)和71.8%(低温环境);PE(B)的遗传力估值为58.0%与14.8%.4.F_2个体的PE(A)或PE(B)呈偏态的双峰连续分布.其中有约5%的PE(A)、10%的PE(B)高于双亲的最高值.据此研究结果,作者建议光敏不育水稻育种应注重对PE性状的选择. 展开更多
关键词 水稻 雄性不育 光周期效应指数 遗传力
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PE可执行程序中Main函数的定位技术 被引量:2
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作者 付文 赵荣彩 +1 位作者 庞建民 张一弛 《计算机工程》 CAS CSCD 北大核心 2010年第16期47-48,51,共3页
针对二进制代码分析中由于无符号表信息造成的难以定位主函数main()的问题,提出一种面向PE可执行程序的main函数定位方法。通过分析PE程序从入口点处开始的执行过程从而提炼相关模板,采用模板匹配的方法定位程序中主函数main()的地址。... 针对二进制代码分析中由于无符号表信息造成的难以定位主函数main()的问题,提出一种面向PE可执行程序的main函数定位方法。通过分析PE程序从入口点处开始的执行过程从而提炼相关模板,采用模板匹配的方法定位程序中主函数main()的地址。实验结果表明,该方法能够有效实现不同编译环境下PE可执行程序的main()函数定位,有助于提高二进制代码分析工具的分析能力。 展开更多
关键词 二进制代码分析 符号表 pe可执行程序 模板匹配
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