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Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment
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作者 Zhao-Jun Zhang Wen-Wei Wang +4 位作者 Jing-Shui Zhen Bo-Cheng Li De-Cheng Cai Yang-Yang Du Hui Huang 《Structural Durability & Health Monitoring》 EI 2025年第1期105-123,共19页
This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment z... This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment zone.An experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was proposed.The composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab specimens.Two methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel beams.The experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal support.In contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading process.As the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan section.When the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span section.Since GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span section.All test specimens experienced compressive failure of concrete at the mid-span section.Calculation results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support section.The proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs. 展开更多
关键词 Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model
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Freezing-Induced Redistribution of Fe(Ⅱ)Species within Clay Minerals for Nonlinear Variations in Hydroxyl Radical Yield and Contaminant Degradation
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作者 Dong Yu Hongbin Peng +3 位作者 Chenglong Yu Wenwen Ji Xin Wang Shengyan Pu 《Journal of Earth Science》 2025年第3期1226-1235,共10页
Hydroxyl radical(·OH)formation from Fe(Ⅱ)-bearing clay mineral oxygenation in the shallow subsurface has been well documented under moderate environmental conditions.However,the impact of freezing processes on t... Hydroxyl radical(·OH)formation from Fe(Ⅱ)-bearing clay mineral oxygenation in the shallow subsurface has been well documented under moderate environmental conditions.However,the impact of freezing processes on the·OH production capability of Fe(Ⅱ)-bearing clay minerals for organic contaminant degradation,particularly in seasonally frozen soils,remains unclear.In this study,we investigated the influence of pre-freezing durations on the mineral proprieties,·OH production,and phenol degradation during the oxygenation of reduced Fe-rich nontronite(rNAu-2)and Fe-poor montmorillonite(rSWy-3).During the freezing process of reduced clay minerals(1 mM Fe(Ⅱ)),the content of edge surface Fe and Fe(Ⅱ)decreased by up to 46%and 58%,respectively,followed by a slight increased as clay mineral particles aggregated and subsequently partially disaggregated.As the edge surface Fe(Ⅱ)is effective in O_(2) activation but less effective in the transformation of H_(2)O_(2) to·OH,the redistribution of edge surface Fe(Ⅱ)leads to that·OH production and phenol degradation increased initially and then decreased with pre-freezing durations ranging from 0 to 20 days.Moreover,the rate constants of phenol degradation for both the rapid and slow reaction phases also first increase and then decrease with freezing time.However,pre-freezing significantly influenced the rapid phase of phenol degradation by rNAu-2 but affected the slow phase by rSWy-3 due to the much higher edge-surface Fe(Ⅱ)content in rNAu-2.Overall,these findings provide novel insights into the mechanism of·OH production and contaminant degradation during the freeze-thaw processes in clay-rich soils. 展开更多
关键词 FREEZE-THAW Fe(Ⅱ)-bearing clay mineral Fe sites redistribution hydroxyl radical contaminant degradation aquifers soils environmental geology
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Composition redistribution-induced dynamic failure of dual-phase 90W-Ni-Fe alloy during adiabatic shear localization process
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作者 Lei Zhang Jia-Tao Zhou +6 位作者 Bai-Shan Chen Yao Wang Yun-Zhu Ma Juan Wang Yu-Feng Huang Chao-Ping Liang Wen-Sheng Liu 《Rare Metals》 2025年第3期1998-2010,共13页
With the upgrade of armor protection materials,higher requirements are put forward for the penetration performance of tungsten alloy kinetic energy armor-piercing projectiles,and the penetration performance is closely... With the upgrade of armor protection materials,higher requirements are put forward for the penetration performance of tungsten alloy kinetic energy armor-piercing projectiles,and the penetration performance is closely related to the adiabatic shear band under extreme stress conditions.Here,the detailed analysis of the adiabatic shear band microstructure evolution of a dual-phase 90W-Ni-Fe alloy under a high strain rate was conducted by combining advanced electron microscopic characterization,while discussing shear fracture from a mechanical perspective under thermoplastic instability.The high temperature and high stress environment inside the adiabatic shear band led to the refinement of the W phase andγ-(Ni,Fe)phase grains to the submicron level,and induced the elements redistribution of W,Ni,and Fe to precipitate W nanocrystalline with hardness as high as 11.7 GPa along the recrystallization grain boundaries of theγ-(Ni,Fe)phase.Mechanical incompatibility caused by the hardness difference between W nanocrystalline andγ-(Ni,Fe)phases led to a strain gradient at the interface.The microvoids preferentially nucleated at the W nanocrystalline/γ-(Ni,Fe)phase interface,then merged to form microcracks and grew further,leading to shear failure. 展开更多
关键词 Adiabatic shear Dual-phase alloy Dynamic recrystallization Composition redistribution High strain rate
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Multicomponent phase field simulation of impact of solidification direction on solute redistribution in Ni-based single crystal superalloys
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作者 Ye-yuan Hu Hu-xiang Xia Qing-yan Xu 《Journal of Iron and Steel Research International》 2025年第9期2926-2936,共11页
With the evolution of nickel-based single crystal superalloys,there is an increase in heavy elements such as Re and Ru.This has made solutal convection more pronounced during the directional solidification process,lea... With the evolution of nickel-based single crystal superalloys,there is an increase in heavy elements such as Re and Ru.This has made solutal convection more pronounced during the directional solidification process,leading to solute redistribution and increasing the risk of casting defects such as low-angle grain boundaries.To avoid casting defects,downward directional solidification(DWS)method is adopted to eliminate solutal convection and change solute redistribution.However,there is currently no in-situ characterization or quantitative simulation studying the solute redistribution during DWS and upward directional solidification(UWS)processes.A multicomponent phase field simulation coupled with lattice Boltzmann method was employed to quantitatively investigate changes in dendrite morphology,solutal convection and deviation of dendrite tips from the perspective of solute redistribution during UWS and DWS processes.The simulation of microstructure agrees well with the experimental results.The mechanism that explains how solutal convection affects side branching behavior is depicted.A novel approach is introduced to characterize dendrite deviation,elucidating the reasons why defects are prone to occur under the influence of natural convection and solute redistribution. 展开更多
关键词 Ni-based single crystal superalloy Solute redistribution Solutal convection Downward directional solidification Multicomponent phase field simulation
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NH_(4)^(+)-Modulated Cathodic Interfacial Spatial Charge Redistribution for High-Performance Dual-Ion Capacitors
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作者 Yumin Chen Ziyang Song +2 位作者 Yaokang Lv Lihua Gan Mingxian Liu 《Nano-Micro Letters》 2025年第5期391-406,共16页
Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical b... Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical behaviors,yet has not been unraveled.Here we propose an NH_(4)^(+)-modulated cationic solvation strategy to optimize cathodic spatial charge distribution and achieve dynamic Zn^(2+)/NH_(4)^(+)co-storage for boosting Zinc hybrid capacitors.Owing to the hierarchical cationic solvated structure in hybrid Zn(CF_(3)SO_(3))_(2)–NH_4CF_(3)SO_(3)electrolyte,high-reactive Zn^(2+)and small-hydrate-sized NH_4(H_(2)O))(4)^(+)induce cathodic interfacial Helmholtz plane reconfiguration,thus effectively enhancing the spatial charge density to activate 20%capacity enhancement.Furthermore,cathodic interfacial adsorbed hydrated NH_(4)^(+)ions afford high-kinetics and ultrastable C···H(NH_(4)^(+))charge storage process due to a much lower desolvation energy barrier compared with heavy and rigid Zn(H_(2)O)_6^(2+)(5.81 vs.14.90 eV).Consequently,physical uptake and multielectron redox of Zn^(2+)/NH_(4)^(+)in carbon cathode enable the zinc capacitor to deliver high capacity(240 mAh g^(-1)at 0.5 A g^(-1)),large-current tolerance(130 mAh g^(-1)at 50 A g^(-1))and ultralong lifespan(400,000cycles).This study gives new insights into the design of cathode–electrolyte interfaces toward advanced zinc-based energy storage. 展开更多
关键词 NH_(4)^(+)-modulated cathodic interface Spatial charge redistribution Zn^(2+)/NH_(4)^(+) co-storage Dual-ion capacitor
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Correction:NH_(4)^(+)‑Modulated Cathodic Interfacial Spatial Charge Redistribution for High‑Performance Dual‑Ion Capacitors
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作者 Yumin Chen Ziyang Song +2 位作者 Yaokang Lv Lihua Gan Mingxian Liu 《Nano-Micro Letters》 2025年第9期94-94,共1页
Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because th... Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because they mistakenly used the incorrect version.The original article[1]has been corrected. 展开更多
关键词 nh modulated cathodic interfacial spatial charge redistribution dual ion capacitors supplementary file correction supplementary file
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Redistribution of iron during directional solidification of metallurgical-grade silicon at low growth rate 被引量:2
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作者 甘传海 方明 +6 位作者 张磊 邱实 李锦堂 姜大川 温书涛 谭毅 罗学涛 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第3期859-864,共6页
Redistribution of iron during directional solidification of metallurgical-grade silicon (MG-Si) was conducted at low growth rate. Concentrations of iron were examined by ICP-MS and figured in solid and liquid phases, ... Redistribution of iron during directional solidification of metallurgical-grade silicon (MG-Si) was conducted at low growth rate. Concentrations of iron were examined by ICP-MS and figured in solid and liquid phases, at grain boundary and in growth direction. Concentrations are significantly different between solid and liquid phases. The thickness of the solute boundary layer is about 4 mm verified by mass balance law, and the effective distribution coefficient is 2.98×10?4. Iron element easily segregates at grain boundary at low growth rate. In growth direction, concentrations are almost constant until 86% ingot height, and they do not meet the Scheil equation completely, which is caused by the low growth rate. The effect of convection on the redistribution of iron was discussed in detail. Especially, the “dead zone” of convection plays an important role in the iron redistribution. 展开更多
关键词 directional solidification metallurgical-grade silicon redistribution IRON grain boundary
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The Involvement of Hydrogen Peroxide in the Regulation of Cell Content Redistribution in the Excised Garlic Scape of Allium sativum
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作者 赵林川 《Developmental and Reproductive Biology》 2002年第2期95-100,共6页
During long term storage at 25℃ in the dark,a large number of cell content were transferred from the senescing scape to the developing cloves,and the transfer from the basal part of scape was earlier than that from t... During long term storage at 25℃ in the dark,a large number of cell content were transferred from the senescing scape to the developing cloves,and the transfer from the basal part of scape was earlier than that from the apical part in the excised garlic scape ( Allium sativum var Taichang).Levels of H 2O 2 decreased in the cloves and significantly increased up to 10 folds and then declined quickly in the scape.Levels of H 2O 2 were enhanced early in the basal part of scape.In the treatment of GA 3 at the cloves,levels of H 2O 2 were strongly enhanced in the cloves and inhibited in the scape,coinciding with the distinct inhibition of cell content tansfer.The results indicated that H 2O 2 may be involved in cell content redistribution and its regulation.3-Amino-1,2,4-triazole (AT) is a specific inhibitor of catalase.Effects of AT on cell content redistribution and levels of H 2O 2 were almost similar to those of GA 3,It further proved the above concept.According to the changes of H 2O 2 leves and activities of peroxidase and catalase in the cloves and in the scape,we suggest that the accumulation of H 2O 2 in the scape was transducted from the cloves,and the decline of H 2O 2 level in the scape with GA 3 or AT at the cloves was mainly through the inhibition of H 2O 2 synthesis in the cloves. 展开更多
关键词 excised garlic scape cell content redistribution REGULATION hydrogen peroxide
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Effect of moisture regime on the redistribution of heavy metals in paddy soil 被引量:35
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作者 Shunan Zheng Mingkui Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第3期434-443,共10页
Sequential extraction procedure was applied to assess the dynamics of solid-phase transformation of added Cu, Pb, Cd, and Hg in a typical Chinese paddy soil incubated under three moisture regimes (75% field capacity,... Sequential extraction procedure was applied to assess the dynamics of solid-phase transformation of added Cu, Pb, Cd, and Hg in a typical Chinese paddy soil incubated under three moisture regimes (75% field capacity, wetting-drying cycle, and flooding). The heavy metals spiked in the soil were time-dependently transferred from the easily extractable fraction (the exchangeable fraction) into less labile fractions (Fe-Mn oxide- and organic matter-bound fractions), and thus reduced lability of the metals. No significant changes were found for the carbonate-bound and residual fractions of the heavy metals in the soil during the whole incubation. Change rate of the mobility factor (MF), a proportion of weakly bound fractions (exchangeable and carbonate-bound) in the total metal of soil, reflected the transformation rate of metal speciation from the labile fractions toward stable fractions. It was found that soil moisture regime did not change the direction and pathways of transformation of metal speciation, but it significantly affected the transformation rate. In general, the paddy soil under flooding regime had higher metal reactivity compared with 75% field capacity and wetting-drying cycle regimes, resulting in the more complete movement of metals toward stable fractions. This might be related to the increased pH, precipitation of the metals with sulfides and higher concentration of amorphous Fe oxides under submerged condition. 展开更多
关键词 heavy metal SPECIATION moisture regime redistribution paddy soil
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Leaching and Redistribution of Nutrients in Surface Layer of Red Soils in Southeast China 被引量:14
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作者 SUN BO ZHANG TAOLIN and ZHAO QIGUO(Institute of Soil Science, the Chinese Academy of Sciences, P.O. Box 821, Naniing 210008 China) 《Pedosphere》 SCIE CAS CSCD 2000年第2期135-142,共8页
The leaching and redistribution of nutrients in the surface layer of 4 types of red soils in SoutheastChina were studied with a lysimeter experiment under field conditions. Results showed that the leachingconcentrated... The leaching and redistribution of nutrients in the surface layer of 4 types of red soils in SoutheastChina were studied with a lysimeter experiment under field conditions. Results showed that the leachingconcentrated in the rainy season (from April to June). Generaily, the leaching of soil nutrients from thesurface layer of red soils was in the order of Ca > Mg > K > NO3-N. In fertilization treatment, the totalamount of soil nutrients leached out of the surface layer in a red soil derived from granite was the highest inall soils. The uptake by grass decreased the leaching of fertilizer ions in surface layer, particularly for NO3-N.Soil total N and exchangeable K, Ca and Mg in the surface layer decreased with leaching and grass uptakeduring the 2 years without new fertilization of urea, Ca(H2PO4)2, KCl, CaCO3 and MgCO3. Ca movedfrom the application layer (0~5 cm) of fertilizer and accumulated in the 10~30 cm depth in the soils studiedexcept that derived from Quaternary red clay. The deficiency of soil exchangeable K will become a seriousdegradation process facing the Southeast China. 展开更多
关键词 LEACHING NUTRIENTS red soils redistribution Southeast China
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Redistribution of Pb, Zn and Cu Fractions in Tailing Soils Treated with Different Extractants 被引量:12
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作者 LIU Yun-Guo WANG Xian-Hai +5 位作者 ZENG Guang-Ming LI Xin ZHOU Chun-Hua FAN Ting LI Yong-Li YUAN Xin-Zhong 《Pedosphere》 SCIE CAS CSCD 2006年第3期312-318,共7页
The efficiency of EDTA, HNO3 and CaCl2 as extractants to remove Pb, Zn and Cu from tailing soils without varying soil pH was investigated with distributions of Pb, Zn and Cu being determined before and after extractio... The efficiency of EDTA, HNO3 and CaCl2 as extractants to remove Pb, Zn and Cu from tailing soils without varying soil pH was investigated with distributions of Pb, Zn and Cu being determined before and after extraction using the sequential extraction procedure of the optimized European Community Bureau of Reference (BCR). Results indicated that EDTA and HNO3 were both effective extracting agents.The extractability of extractants for Pb and Zn was in the order EDTA > HNO3 > CaCl2, while for Cu it was HNO3 > EDTA > CaCl2. After EDTA extraction, the proportion of Pb, Zn and Cu in the four fractions varied greatly, which was related to the strong extraction and complexation ability. Before and after extraction with HNO3 and CaCl2, the percentages of Pb, Zn and Cu in the reducible, oxidizable and residual fractions changed little compared to the acid-extractable fraction. The lability of metal in the soil and the kinds of extractants were the factors controlling the effects of metal extraction. 展开更多
关键词 BCR extraction FRACTION heavy metals redistribution
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Patterns,magnitude,and controlling factors of hydraulic redistribution of soil water by Tamarix ramosissima roots 被引量:12
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作者 TengFei YU Qi FENG +2 位作者 JianHua SI HaiYang XI Wei LI 《Journal of Arid Land》 SCIE CSCD 2013年第3期396-407,共12页
Tamarix spp. (Saltcedar) is a facultative phreatophyte that can tolerate drought when groundwater is not accessed. In addition to deep water uptake, hydraulic redistribution (HR) is another factor contributing to ... Tamarix spp. (Saltcedar) is a facultative phreatophyte that can tolerate drought when groundwater is not accessed. In addition to deep water uptake, hydraulic redistribution (HR) is another factor contributing to the drought tolerance of Tarnarix spp. In this study, data on soil volumetric moisture content (0), lateral root sap flow, and relevant climate variables were used to investigate the patterns, magnitude, and controlling factors of HR of soil water by roots of Tamarix ramosissima Ledeb. in an extremely arid land in Northwest China. Results showed evident diurnal fluctuations in 0 at the depths of 30 and 50 cm, indicating "hydraulic lift" (HL). 0 increased remarkably at 10 and 140 cm but decreased at 30 and 50 cm and slightly changed at 80 cm after rainfall, suggesting a possible "hydraulic descent" (HD). However, no direct evidence was observed in the negative flow of lateral roots, supporting HR (including HL and HD) of T. ramosissima. The HR pathway unlikely occurred via lateral roots; instead, HR possibly occurred through adventitious roots with a diameter of 2-5 mm and a length of 60-100 cm. HR at depths of 20-60 cm ranged from 0.01-1.77 mm/d with an average of 0.43 mm/d, which accounted for an average of 22% of the estimated seasonal total water depletion at 0-160 cm during the growing season. The climate factors, particularly vapor pressure deficit and soil water potential gradient, accounted for at least 33% and 45% of HR variations with depths and years, respectively. In summary, T. ramosissima can be added to the wide list of existing species involved in HR. High levels of HR may represent a considerable fraction of daily soil water depletion and substantially improve plant water status. HR could vary tremendously in terms of years and depths, and this variation could be attributed to climate factors and soil water potential gradient. 展开更多
关键词 drought tolerance phreatophyte hydraulic redistribution root sap flow Tamarix ramosissima
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Variation of nutrient fluxes by rainfall redistribution processes in the forest canopy of an urban larch plantation in northeast China 被引量:6
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作者 Houcai Sheng Na Guo +1 位作者 Cunyong Ju Tijiu Cai 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第4期1259-1269,共11页
Atmospheric deposition(dry and wet deposition)is one of the primary sources of chemical inputs to terrestrial ecosystems and replenishes the nutrient pool in forest ecosystems.Precipitation often acts as a primary tra... Atmospheric deposition(dry and wet deposition)is one of the primary sources of chemical inputs to terrestrial ecosystems and replenishes the nutrient pool in forest ecosystems.Precipitation often acts as a primary transporting agent and solvent;thus,nutrient cycles in forests are closely linked to hydrological processes.We collected precipitation data during a growing season to explore variations in nutrient cycling and nutrient balances in the rainfall redistribution process(wet deposition)in a larch plantation in northeast China.We measured nutrient(NO_(3)^(-),PO_(4)^(3−),Cl^(−),K,Ca,Na,and Mg)inputs via bulk precipitation,throughfall and stemfl ow,and used a canopy budget model to estimate nutrient fl uxes via canopy exchange.Our results suggest that the average concentrations of the base cation(K,Ca,Na,and Mg)showed the following order:stemfl ow>throughfall>bulk precipitation.Throughfall and stemfl ow chemistry dramatically fl uctuated over the growing season when net fl uxes(throughfall+stemfl ow—bulk precipitation)of NO−3,PO3−4,SO2−4,Cl−,K,Ca,Na,and Mg were−6.676 kg·ha^(-1),−1.094 kg·ha^(-1),−2.371 kg·ha^(-1),1.975 kg·ha^(-1),0.470 kg·ha^(-1),−5.202 kg·ha^(-1),−0.336 kg·ha^(-1),and 1.397 kg·ha^(-1),respectively.These results suggest that NO−3,PO3−4,SO2−4,Ca,and Na were retained,while Cl−,K,and Mg were washed off by throughfall and stemfl ow. 展开更多
关键词 Rainfall redistribution Aqueous fluxes Water chemistry Macronutrients input Plantation forest HARBIN
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An Analytical Solution for One-Dimensional Water Infiltration and Redistribution in Unsaturated Soil 被引量:7
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作者 WANG Quan-Jiu R. HORTON FAN Jun 《Pedosphere》 SCIE CAS CSCD 2009年第1期104-110,共7页
Soil infiltration and redistribution are important processes in field water cycle, and it is necessary to develop a simple model to describe the processes. In this study, an algebraic solution for one-dimensional wate... Soil infiltration and redistribution are important processes in field water cycle, and it is necessary to develop a simple model to describe the processes. In this study, an algebraic solution for one-dimensional water infiltration and redistribution without evaporation in unsaturated soil was developed based on Richards equation. The algebraic solution had three parameters, namely, the saturated water conductivity, the comprehensive shape coefficient of the soil water content distribution, and the soil suction allocation coefficient. To analyze the physical features of these parameters, a relationship between the Green-Ampt model and the algebraic solution was established. The three parameters were estimated based on experimental observations, whereas the soil water content and the water infiltration duration were calculated using the algebraic solution. The calculated soil water content and infiltration duration were compared with the experimental observations, and the results indicated that the algebraic solution accurately described the unsaturated soil water flow processes. 展开更多
关键词 algebraic solution Green-Ampt model soil water infiltration and redistribution unsaturated soil
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Effect of pre-tensioned rock bolts on stress redistribution around a roadway—insight from numerical modeling 被引量:12
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作者 GAO Fu-qiang KANG Hong-pu 《Journal of China University of Mining and Technology》 EI 2008年第4期509-515,共7页
The importance of the pre-tensioned force of rock bolts has been recognized by more and more researchers. To investi- gate the effect of pre-tensioned rock bolts on stress redistribution around roadways, a numerical a... The importance of the pre-tensioned force of rock bolts has been recognized by more and more researchers. To investi- gate the effect of pre-tensioned rock bolts on stress redistribution around roadways, a numerical analysis was carried out using FLAC3D and a special post-process methodology, using surfer, is proposed to process the numerical simulation results. The results indicate that pre-tensioned rock bolts have a significant effect on stress redistribution around a roadway. In the roof, pre-tensioned rock bolts greatly increase vertical stress; as a result, the strength of the rock mass increased significantly which results in a greater capacity of bearing a large horizontal stress. The horizontal stress decreases in the upper section of the roof, indicating that pre-tensioned rock bolts significantly reduce the coefficient and the size of the region concentration of horizontal stress. At the lat- eral side, pre-tensioned rock bolts greatly increase the horizontal stress; therefore, the rock mass strength significantly increases which results also in a greater capacity of bearing a large vertical stress. The greater the size of pre-tensioned force, the larger the region of stress redistribution around a roadway is affected and the higher the size of the stress on the roadway surface the more the rock mass strength increases. 展开更多
关键词 pre-tensioned rock bolts stress redistribution numerical simulation
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Load-redistribution strategy based on time-varying load against cascading failure of complex network 被引量:5
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作者 刘军 熊庆宇 +2 位作者 石欣 王楷 石为人 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期371-377,共7页
Cascading failure can cause great damage to complex networks, so it is of great significance to improve the network robustness against cascading failure. Many previous existing works on load-redistribution strategies ... Cascading failure can cause great damage to complex networks, so it is of great significance to improve the network robustness against cascading failure. Many previous existing works on load-redistribution strategies require global information, which is not suitable for large scale networks, and some strategies based on local information assume that the load of a node is always its initial load before the network is attacked, and the load of the failure node is redistributed to its neighbors according to their initial load or initial residual capacity. This paper proposes a new load-redistribution strategy based on local information considering an ever-changing load. It redistributes the loads of the failure node to its nearest neighbors according to their current residual capacity, which makes full use of the residual capacity of the network. Experiments are conducted on two typical networks and two real networks, and the experimental results show that the new load-redistribution strategy can reduce the size of cascading failure efficiently. 展开更多
关键词 load redistribution time-varying load cascading failure complex networks
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Effects of nitrogen fertilization strategies on nitrogen use efficiency in physiology, recovery, and agronomy and redistribution of dry matter accumulation and nitrogen accumulation in two typical rice cultivars in Zhejiang, China 被引量:3
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作者 XIE Wen-xia, WANG Guang-huo, ZHANG Qi-chun, GUO Hai-chao (Institute for Soil and Water Resources and Environment, Zhejiang University, Hangzhou 310029, China) 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第3期208-216,共9页
Field experiments were conducted in farmers’ rice fields in 2001 and 2002 to study the effects of nitrogen (N) man-agement strategies on N use efficiency in recovery (RE), agronomy (AE) and physiology (PE) and redist... Field experiments were conducted in farmers’ rice fields in 2001 and 2002 to study the effects of nitrogen (N) man-agement strategies on N use efficiency in recovery (RE), agronomy (AE) and physiology (PE) and redistribution of dry matter accumulation (DMA) and nitrogen accumulation (NA) in two typical rice cultivars in Jinhua, Zhejiang Province. This study aimed mainly at identifying the possible causes of poor fertilizer N use efficiency (NUE) of rice in Zhejiang by comparing farmers’ fertilizer practice (FFP) with advanced site-specific nutrient management (SSNM) and real-time N management (RTNM). The results showed that compared to FFP, SSNM and RTNM reduced DMA and NA before panicle initiation and increased DMA and NA at post-flowering. There is no significant difference between SSNM and FFP in post-flowering dry matter redistribution (post-DMR) and post-flowering nitrogen redistribution (post-NR). These results suggest that high input rate of fertilizer N and improper fertilizer N timing are the main factors causing low NUE of irrigated rice in the farmer’s routine practice of Zhejiang. With SSNM, about 15% of the current total N input in direct-seeding early rice and 45% in single rice could be reduced without yield loss in Zhejiang, China. 展开更多
关键词 RECOVERY N USE EFFICIENCY (RE) Agronomic N USE EFFICIENCY (AE) Physiological N USE EFFICIENCY (PE) Nitrogen management Rice Accumulation and redistribution
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Stress redistribution of simply supported reinforced concrete beams under fire conditions 被引量:4
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作者 DING Fa-xing LI Zhe YU Zhi-wu 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第9期2093-2106,共14页
This study presents experimental and numerical investigations of simply supported steel reinforced concrete(RC)beams under fire.The temperature field of cross sections,the vertical deflection at mid-span,and specifica... This study presents experimental and numerical investigations of simply supported steel reinforced concrete(RC)beams under fire.The temperature field of cross sections,the vertical deflection at mid-span,and specifically the axial expansion displacement at beam-ends were measured during the fire tests.A novel finite element(FE)model of a RC beam under fire was developed,in which the water loss in the heat transfer analysis and the concrete transient strain in the mechanical analysis were considered.Based on the validated FE model proposed in this study,parametric studies were conducted to investigate the effects of the beam type,the protective layer thickness,and the load ratio on the thermal and mechanical behavior of simply supported RC beams.It was found that greater fire resistance and fire performance of girder beams in comparison to secondary beams contributed to the non-structural reinforcements,which effectively compensated for the reduced tensile capacities of structural reinforcements because of the degradation of the material properties.In addition,the history of normal stress distributions of concrete under fire can be divided into three phases:expansion,stress redistribution and plateau phases. 展开更多
关键词 reinforced concrete beam transient strain fire condition parametric analysis stress redistribution
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Exercise induces tissue hypoxia and HIF-1α redistribution in the small intestine 被引量:4
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作者 Die Wu Wei Cao +3 位作者 Dao Xiang Yi-Ping Hu Beibei Luo Peijie Chen 《Journal of Sport and Health Science》 SCIE 2020年第1期82-89,共8页
Background:Exercise induces blood flow redistribution among tissues,leading to splanchnic hypoperfusion.Intestinal epithelial cells are positioned between the anaerobic lumen and the highly metabolic lamina propria wi... Background:Exercise induces blood flow redistribution among tissues,leading to splanchnic hypoperfusion.Intestinal epithelial cells are positioned between the anaerobic lumen and the highly metabolic lamina propria with an oxygen gradient.Hypoxia-inducible factor(HIF)-la is pivotal in the transcriptional response to the oxygen flux.Methods:In this study,the pimonidazole hydrochloride staining was applied to observe the tissue hypoxia in different organs,which might be affected by the blood flow redistribution.The HIF-la luciferase reporter ROSA26 oxygen-dependent degradation domain(ODD)-Luc/^+mouse model(ODD domain-Luc;female,n=3-6/group) was used to detect the HIF-la expression in the intestine.We used 3 swimming models:moderate exercise for 30 min,heavy-intensity exercise bearing 5% bodyweight for 1.5 h,and long-time exercise for 3 h.Results:We found that 1 session of swimming at different intensities could induce tissue hypoxia redistribution in the small intestine,colon,liver and kidney,but not in the spleen,heart,and skeletal muscle.Our data showed that exercise exacerbated the extent of physiological hypoxia in the small intestine.Next,using ODD-Luc mice,we found that moderate exercise increased the in vivo HIF-1α level in the small intestine.The postexercise HIF-1α level was gradually decreased in a time-dependent manner.Interestingly,the redistribution of tissue hypoxia and the increase of HIF-la expression were not related to the exercise intensity and duration.Conclusion:This study provided evidence that the small intestine is the primary target organ for exercise-induced tissue hypoxia and HIF-la redistribution,suggesting that HIF-1α may be a potential target for the regulation of gastrointestinal functions after exercise. 展开更多
关键词 Blood flow redistribution Hypoxia-inducible factor-1α ODD-Luc Pimonidazole HCl SWIMMING
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Verifiable Secret Redistribution for Proactive Secret Sharing Schemes 被引量:4
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作者 于佳 孔凡玉 李大兴 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第2期236-241,共6页
A new scheme to verifiably redistribute a secret from the old to new shareholders without reconstruction of the secret is presented in this paper. The scheme allows redistribution between different access structures a... A new scheme to verifiably redistribute a secret from the old to new shareholders without reconstruction of the secret is presented in this paper. The scheme allows redistribution between different access structures and between different threshold schemes. A point worth mentioning is that this verifiable secret redistribution (VSR) scheme can identify dishonest old shareholders during redistribution without any assumption. A certain technique is adopted to verify the correctness of the old shares of the secret. As a result, the scheme is very efficient. It can be applied to proactive secret sharing (PSS) schemes to construct more flexible and practical proactive secret sharing schemes. 展开更多
关键词 secret sharing verifiable secret redistribution proactive secret sharing
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