期刊文献+
共找到18篇文章
< 1 >
每页显示 20 50 100
Residual effects of TMOF-Bti formulations against 1^(st) instar Aedes aegypti Linnaeus larvae outside laboratory
1
作者 Saiful AN Lau MS +1 位作者 Sulaiman S Hidayatulfathi O 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第4期315-319,共5页
Objective:To evaluate the effectiveness and residual effects of trypsin modulating ecstatic factor-Bacillus thuringiensis israeliensis(TMOF-Bti) formulations against Aedes aegypti(Ae. aegypti)(L) larvae at UKM Campus ... Objective:To evaluate the effectiveness and residual effects of trypsin modulating ecstatic factor-Bacillus thuringiensis israeliensis(TMOF-Bti) formulations against Aedes aegypti(Ae. aegypti)(L) larvae at UKM Campus Kuala Lumpur.Methods:Twenty first instar Ae.aegypti larvae were added in each bucket containing 4 L of water supplied with crushed dried-leaf powder as their source of food.Combination of TMOF-Bti in rice husk formulation with the following weights viz 10,25,50 and 100 mg,respectively in duplicate was distributed in the buckets;while TMOF-Bti in wettable powder formulation each weighing viz 2,5,10 and 20 mg,respectively in duplicate was also placed in the buckets.The control buckets run in duplicate with 4 L of water and 20 first instar Ae.aegypti larvae.All buckets were covered with mosquito netting.Larval mortality was recorded after 24 hours and weekly for five weeks.A new batch of 20 1^(st) instar larvae Ae.aegypti was introduced into each bucket weekly without additional TMOF-Bti rice husk formulation or wettable powder.The experiment was repeated for four times.Results:The result of the study showed that all formulations were very effective on the first two weeks by giving 100% larval mortality for all concentrations applied.The TMOF(2%) + Bti(2%) had a good residual effect until the end of 3^(rd) week,TMOF(4%) + Bti(4%) until 4^(th) week,wettable powder TMOF(20%) + Bti(20%) until the third week.Condusions:From the results it can be concluded that the TMOF-Bti formulations can be utilized in dengue vector control. 展开更多
关键词 TMOF-Bti formulations 1^(st) instar Aedes aegypti Outside laboratory residual effect LARVAE DENGUE Dengue vector control Mosquito Larval mortality
下载PDF
Residual Effect of Fipronil in Eriocheir sinensis
2
作者 Xi CHEN Cong ZHANG +3 位作者 Chao SONG Longxiang FANG Xinyue DONG Jiazhang CHEN 《Agricultural Biotechnology》 CAS 2020年第4期140-143,共4页
The residual effects of fipronil aqueous solutions(at mass concentrations of 10,30 and 50μg/L,respectively)on Eriocheir sinensis were investigated by the semi-static experiment method.The results showed that among th... The residual effects of fipronil aqueous solutions(at mass concentrations of 10,30 and 50μg/L,respectively)on Eriocheir sinensis were investigated by the semi-static experiment method.The results showed that among the treatment groups with different mass concentrations,the high mass concentration group contained fipronil at a significantly higher content in the crab legs than the low-mass concentration group,and also a significantly higher content in the body than the low mass concentration group.There were no significant differences in the content of fipronil between different parts of E.sinensis.The trend of fipronil-enriched parts was from the legs to the body to the gonads.Fipronil residue in E.sinensis had no sex selectivity,but it enriched faster in female E.sinensis than males.This study provides a certain reference for dealing with related fishery pollution accidents. 展开更多
关键词 FIPRONIL Eriocheir sinensis residual effect
下载PDF
Residual effects of tobacco biochar along with different fixing agents on stabilization of trace elements in multi-metal contaminated soils 被引量:3
3
作者 Altaf Hussain Lahori Monika Mierzwa-Hersztek +5 位作者 Muhammad Rashid Shahmir Ali Kalhoro Mehrunisa Memon Zobia Naheed Muneer Ahmed Zengqiang Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第1期299-309,共11页
The residual effect of tobacco biochar(TB≥500°C)mono and co-application with Cahydroxide(CH),Ca-bentonite(CB)and natural zeolite(NZ)on the bio-availability of trace elements TE(s)in alkaline soils has not been d... The residual effect of tobacco biochar(TB≥500°C)mono and co-application with Cahydroxide(CH),Ca-bentonite(CB)and natural zeolite(NZ)on the bio-availability of trace elements TE(s)in alkaline soils has not been deeply studied yet.A pot study that had earlier been investigated TB mono and blended with CH,CB and NZ on the immobilization of Pb,Cu Cd,and Zn by Chinese cabbage.Maize crop in the rotation was selected as test plant to assess the residual impact of amendments on stabilization of Pb,Cu Cd,and Zn in mine polluted(M-P),smelter heavily and low polluted(S-HP and S-LP,respectively)soils.The obtained results showed that stabilization of Pb,Cd,Cu and Zn reached 63.84% with TB+CB,61.19% with TB+CH,83.31% with TB+CH and 35.27% with TB+CH for M-P soil,36.46% with TB+NZ,38.46% with TB+NZ,19.40% with TB+CH and 62.43% with TB+CH for S-LP soil,52.94%TB+NZ,57.65% with TB+NZ,52.94% with TB+NZ,and 28.44% with TB+CH for S-LP soil.Conversely,TB+CH and TB alone had mobilized Pb and Zn up to19.29% and 34.96% in M-P soil.The mobility of Zn reached 8.38% with TB+CB and 66.03% with TB for S-HP and S-LP soils.The uptake and accumulation of Pb,Cd,Cu and Zn in shoot and root were reduced in three polluted soils.Overall,the combination of TB along with CH,CB and NZ has been proven to be effective in Pb,Cd,Cu and Zn polluted mine/smelter soils restoration. 展开更多
关键词 Tobacco biochar residual effect Trace elements stabilization MAIZE Soil remediation
原文传递
Effect of Residual Charge Carrier on the Performance of a Graphene Field Effect Transistor
4
作者 Sedighe Salimian Mohammad Esmaeil Azim Araghi 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期113-117,共5页
The temperature-dependent effect of residual charge carrier (no), at the Dirac point, on mobility is studied. We fabricate and characterize a graphene field effect transistor (GFET) using 7nm TiO2 as the top-gate ... The temperature-dependent effect of residual charge carrier (no), at the Dirac point, on mobility is studied. We fabricate and characterize a graphene field effect transistor (GFET) using 7nm TiO2 as the top-gate dielectric. The temperature-dependent gate voltage-drain current and room temperature gate capacitance are measured to extract the carrier mobility and to estimate the quantum capacitance of the GFET. The device shows the mobility value of gOO cm^2 /V.s at room temperature and it decreases to 45 cm^2 /V.s for 20 K due to the increase of n0. These results indicate that the phonon scattering is not the dominant process for the unevenness dielectric layer while the coulomb scattering by charged impurities degrades the device characteristically at low temperature. 展开更多
关键词 of it by effect of residual Charge Carrier on the Performance of a Graphene Field effect Transistor on IS VTG HIGH for into that
下载PDF
Composition Dependence and Irradation Effects on Residual Resistivity in Cu-Al Alloys
5
作者 M. Sadiq and Nazma Ikram(Centre for Solid State Physics, University of the Punjab, New Campus, Lahore-54590, Pakistan)A. Shaukat(Physics Dept., University of the Punjab, New Campus, Lahore-54590, Pakistan)Farid A. Khwaja(Dept. of Physics, Quaid-e-Azam Uni 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1996年第4期261-266,共6页
Residual electrical resistivity due to short-range order has been calculated for Cu100-xAlx (x=9.13,13.56, 14.5 and 14.76 in at pct) alloys using pseudopotential approach, and the results have been discussed in the li... Residual electrical resistivity due to short-range order has been calculated for Cu100-xAlx (x=9.13,13.56, 14.5 and 14.76 in at pct) alloys using pseudopotential approach, and the results have been discussed in the light of experimental studies of the local-order structure of these alloys. In case of Cu85.5Al14.5, change in the total residual electrical resistivity due to neutron-irradiation effects has been estimated by including contributions from the short-range order and static atomic displacement correction. Our results show a decrease in the residual resistivity in the irradiated Cu-Al solid solution as compared to the unirradiated sample. This is in accordance with the experimental results 展开更多
关键词 AL Composition Dependence and Irradation effects on residual Resistivity in Cu-Al Alloys CU
下载PDF
Effect and mechanism of coking residual ammonia water treating by flue gas
6
《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第2期237-246,共10页
关键词 effect and mechanism of coking residual ammonia water
下载PDF
Effect of Long-Term Application of Compost on Some Chemical Properties of Wheat Rhizosphere and NonRhizosphere Soils 被引量:9
7
作者 SHENALIN LIXUEYUAN 《Pedosphere》 SCIE CAS CSCD 1996年第4期355-363,共9页
Compost of dtherent rates was applied to artificial field plots of a low humic andosol at National Agriculture Research Center (NARC) of Japan for 15 or 28 years, and their effects on the chemical properties of wheat ... Compost of dtherent rates was applied to artificial field plots of a low humic andosol at National Agriculture Research Center (NARC) of Japan for 15 or 28 years, and their effects on the chemical properties of wheat rhisosphere soil and nonrhizosphere soil were measured.Continuous application of compost for 28 years resulted in raise of soil C, N, P, pH and exchangeable bases. The building up of organic matter in the soil occurred slowly A residual effect of the compost on soil chemical properties was still present after 13 years of no application, but this effect was weaker in comparison with that of the continuous application treatments. In the rhizosphere soil, NaHCO3-extracted P and exchangeable Ca were higher than those in the bulk soil. The removal of free organic acid slightly affected the soil pH, especially, the rhizosphere soil pH. The raise of soil pH may result from the increase of exchangeable base by the application of compost. 展开更多
关键词 chemical properties COMPOST organic acid residual effect rhizosphere
下载PDF
Effects of improved fallow with Sesbania sesban on maize productivity and Striga hermonthica infestation in Western Kenya 被引量:1
8
作者 Hans Sjogren Keith D Shepherd Anders Karlsson 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第3期379-386,400,共9页
Striga hermonthica is a major constraint to smallholder sub-sistence agriculture production in the sub-Saharan African region. Low soil fertility and overall environmental degradation has contributed to the build-up o... Striga hermonthica is a major constraint to smallholder sub-sistence agriculture production in the sub-Saharan African region. Low soil fertility and overall environmental degradation has contributed to the build-up of the parasitic weed infestation. Improved cropping systems have to be introduced to address the interrelated problems of S. her-monthica and soil fertility decline. Thus, the effects of improved fallow with leguminous shrub Sesbania sesban on maize yields and levels of S. hermonthica infestation on farm land in the bimodal highlands of western Kenya were investigated. The experimental treatments were arranged in a phased entry, and randomized complete block scheme were six months Sesbania fallow, 18 months Sesbania fallow, six months natural fallow consisting of regrowth of natural vegetation without cultivation, 18 months natural fallow, continuous maize cropping without fertilizer application, and continuous maize cropping with P and N fertilization. Results show that Sesbania fallows significantly (p0.05) increase maize yield relative to continuous unfertilized maize. S. hermonthica plant populations decrease in continuous maize between the first season (mean = 428 000 ± 63 000 ha-1) and second season (mean=51 000 ± 15 000 ha-1), presumably in response to good weed management. S. hermonthica seed populations in the soil decrease throughout the duration of the experi-ment in the continuous maize treatments. Short-duration Sesbania fal-lows can provide modest yield improvements relative to continuous unfertilized maize, but short-duration weedy fallows are ineffective. Continuous maize cultivation with good weed control may provide more effective S. hermonthica control than fallowing. 展开更多
关键词 AGROFORESTRY crop yield improved fallow residual effect root parasite soil fertility replenishment
下载PDF
Impact of sampling interval on variance components of epoch-wise residual error in relative GPS positioning: A case study of a 40-km-long baseline
9
作者 Darko Andic 《Geodesy and Geodynamics》 CSCD 2021年第5期368-380,共13页
The study presents sampling interval impacts on variance components of the epoch-wise residual errors in relative GPS positioning. In the variance components estimation process, the 2-way nested ANOVA method was used.... The study presents sampling interval impacts on variance components of the epoch-wise residual errors in relative GPS positioning. In the variance components estimation process, the 2-way nested ANOVA method was used. For that purpose, GPS observation data during four months at two permanent GPS stations, establishing a 40-km-long baseline as a part of the Montenegrin permanent network(Monte Pos), were used. The study results showed that there is no statistically significant impact of sampling interval changes on epoch-wise variance components related to the residual tropospheric and ionospheric delays(effect a) when it comes to such a baseline. However, it is not the case with epoch-wise variance components related to the interstation-distance-independent residual ‘far-field’ multipath effect(effect b). It turned out that the absolute values of relative differences of standard deviations of the effect a on the relative GPS coordinates(e, n and u) had maximum values 11.1%, 10.2% and 8.9%,respectively. Keeping the same order of presentation for the effect b, the values of 5.9%, 9.9% and 12.5%were obtained. In addition, absolute values of relative differences of standard deviations of horizontal and vertical position had maximum values of 3.8% and 7.7%, respectively. 展开更多
关键词 Relative GPS positioning residual effects Variance components Positional accuracy Sampling interval
下载PDF
Toxic Effects of Pirimiphos-methyl Residues on Rats
10
作者 NEkO K.NEKOVI VESELA .KARAN +1 位作者 VESNA SABOVLJEVI SLAVOLJUB LJ.VITOROVI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1989年第2期115-130,共16页
This study analyzes the level of total and bound pirimiphos-methyl residues in treated wheat grain and its toxic effects on rats.Wheat grain was treated with[(14)~C]pirimiphos-methyl of 16.36 mCi/mmol specific activit... This study analyzes the level of total and bound pirimiphos-methyl residues in treated wheat grain and its toxic effects on rats.Wheat grain was treated with[(14)~C]pirimiphos-methyl of 16.36 mCi/mmol specific activity to determine the bioavailability of bound residues in rats.At the same time,grain was treated with nonlabeled pirimiphos-methyl as required to determine any possible toxic effects of bound residues in a subacute feeding study in rats.Two dose levels were used:10 and 100 ppm(the former being the recommended dose level in practical treatment). Estimation of the type of residues was performed at intervals of 0,30,90,120,150,and 180 days.During and after the animal feeding study,changes in body weight gain,organ weight, cholinesterase activity,serum enzyme activity,and hematology were investigated.There is an indication that bound residues of the pesticide pirimiphos-methyl provoke toxic effects to some extent.1989 Academic Press.Inc. 展开更多
关键词 In Toxic effects of Pirimiphos-methyl Residues on Rats
下载PDF
Toxic Effects of Bound Malathion Residues in Rats
11
作者 NESKOK.NESKOVIC VERAD.VOJINOVIC +1 位作者 VESELAZ.KARAN SLAVOLJUBLJ.VITOROVIC 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1991年第4期423-432,共10页
The level of bound malathion residues in treated wheat grain and its toxic effects on rats were investigated. Wheat grain was treated with [14C] malathion (specific activity: 2.76 MBq/mg) to determine the bioavailabil... The level of bound malathion residues in treated wheat grain and its toxic effects on rats were investigated. Wheat grain was treated with [14C] malathion (specific activity: 2.76 MBq/mg) to determine the bioavailability of bound residues in rats. At the same time, grain was treated with nonlabeled malathion to test for possible toxic effects of bound residues in a subchronic (90 days) feeding study in rats at two dose levels. 10 and 100 ppm.It was observed that the level of malathion-bound residues amounted to 11.28% of the applied dose (for six months). Also, it was noted that the main route of [14C]-malathion excretion was through the urine. This signifies that grain-bound malathion was bioavailable. In subchronic test on rats bound malathion residues (both dose levels) induced effects to some extent in organ weight (spleen and adrenals), and blood ChE activity. In both, males and females, there was an increase in SGPT activity (lower dose), and in alkaline phosphatase in females (higher dose). Hematological data showed changes only in hemoglobin concentration in males (both dose levels). 展开更多
关键词 In Toxic effects of Bound Malathion Residues in Rats
下载PDF
An Air Defense Weapon Target Assignment Method Based on Multi-Objective Artificial Bee Colony Algorithm 被引量:1
12
作者 Huaixi Xing Qinghua Xing 《Computers, Materials & Continua》 SCIE EI 2023年第9期2685-2705,共21页
With the advancement of combat equipment technology and combat concepts,new requirements have been put forward for air defense operations during a group target attack.To achieve high-efficiency and lowloss defensive o... With the advancement of combat equipment technology and combat concepts,new requirements have been put forward for air defense operations during a group target attack.To achieve high-efficiency and lowloss defensive operations,a reasonable air defense weapon assignment strategy is a key step.In this paper,a multi-objective and multi-constraints weapon target assignment(WTA)model is established that aims to minimize the defensive resource loss,minimize total weapon consumption,and minimize the target residual effectiveness.An optimization framework of air defense weapon mission scheduling based on the multiobjective artificial bee colony(MOABC)algorithm is proposed.The solution for point-to-point saturated attack targets at different operational scales is achieved by encoding the nectar with real numbers.Simulations are performed for an imagined air defense scenario,where air defense weapons are saturated.The non-dominated solution sets are obtained by the MOABC algorithm to meet the operational demand.In the case where there are more weapons than targets,more diverse assignment schemes can be selected.According to the inverse generation distance(IGD)index,the convergence and diversity for the solutions of the non-dominated sorting genetic algorithm III(NSGA-III)algorithm and the MOABC algorithm are compared and analyzed.The results prove that the MOABC algorithm has better convergence and the solutions are more evenly distributed among the solution space. 展开更多
关键词 Weapon target assignment multi-objective artificial bee colony air defense defensive resource loss total weapon consumption target residual effectiveness
下载PDF
Fate of ^(15)N-Labeled Urea Under a Winter Wheat-Summer Maize Rotation on the North China Plain 被引量:44
13
作者 JU Xiao-Tang LIU Xue-Jun +1 位作者 PAN Jia-Rong ZHANG Fu-Suo 《Pedosphere》 SCIE CAS CSCD 2007年第1期52-61,共10页
A field experiment was conducted to investigate the fate of ^15N-labeled urea and its residual effect under the winter wheat (Triticum aestivum L.) and summer maize (Zea mays L.) rotation system on the North China... A field experiment was conducted to investigate the fate of ^15N-labeled urea and its residual effect under the winter wheat (Triticum aestivum L.) and summer maize (Zea mays L.) rotation system on the North China Plain. Compared to a conventional application rate of 360 kg N ha^-1 (N360), a reduced rate of 120 kg N ha^-1 (N120) led to a significant increase (P 〈 0.05) in wheat yield and no significant differences were found for maize. However, in the 0-100 cm soil profile at harvest, compared with N360, N120 led to significant decreases (P 〈 0.05) of percent residual N and percent unaccounted-for N, which possibly reflected losses from the managed system. Of the residual fertilizer N in the soil profile, 25.6%-44.7% and 20.7%-38.2% for N120 and N360, respectively, were in the organic N pool, whereas 0.3%-3.0% and 11.2%-24.4%, correspondingly, were in the nitrate pool, indicating a higher potential for leaching loss associated with application at the conventional rate. Recovery of residual N in the soil profile by succeeding crops was less than 7.5% of the applied N. For N120, total soil N balance was negative; however, there was still considerable mineral N (NH4^+-N and NO3^--N) in the soil profile after harvest. Therefore, N120 could be considered ngronomically acceptable in the short run, but for long-term sustainability, the N rate should be recommended based on a soil mineral N test and a plant tissue nitrate test to maintain the soil fertility. 展开更多
关键词 ^15N-labeled urea nitrogen recovery nitrogen residual effect North China Plain winter wheat-summer maize rotation
下载PDF
Water and sediment quality parameters in the Chalan Beel, the largest wetland of Bangladesh
14
作者 SAYEED Md.Abu HOSSAIN Mostafa Ali Reza +3 位作者 WAHAB Md.Abdul HASAN Md.Tawheed SIMON Kumar Das MAZUMDER Sabuj Kanti 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第4期895-904,共10页
A study was conducted to investigate the status of the water and sediment quality in the Chalan Beel——a major fresh water fish reservoir of the country for a period of one year from July 2007 to June 2008. The mean ... A study was conducted to investigate the status of the water and sediment quality in the Chalan Beel——a major fresh water fish reservoir of the country for a period of one year from July 2007 to June 2008. The mean values of water quality parameters(depth: 214.73±152.22 cm, temperature 27.68±4.26℃, transparency 123±82 cm, p H 9.7±0.47, total alkalinity 137±42 mg/L, conductivity 307±147 μs/cm, total dissolved solids 183±89 mg/L, ammonia-N 0.27±0.39 mg/L, nitrate-N 0.09±0.07 mg/L, phosphate-P 2.01±2.53 mg/L) and sediment quality parameters(p H 7.21±0.35, organic matter 2.59±0.52%, total nitrogen 0.09±0.04%, available phosphorus 5.4±3.6 Meq./100 g and exchangeable potassium 0.43±0.14 Meq./100 g) were within the range recommended for most of the inland fishes of Bangladesh. Although the water and sediment quality parameters except ammonia and phosphate are in the suitable range, the overall results suggest that better management techniques should be practiced in order to overcome the declining trend of associated aquatic life(fauna and flora) of this important fresh water body of Bangladesh. 展开更多
关键词 Chalan Beel total dissolve solids TRANSPARENCY residual effect organic matter sustainable management
下载PDF
Enhanced Growth and Yield Performance of Cassava Peel Compost and Mineral Fertilizer on Corchorus olitorius L.
15
作者 Ibidunni Temitope Okesiji Amudalat Bolanle Olaniyan +1 位作者 James Alabi Adediran Adeniyi Olumuyiwa Togun 《Journal of Agricultural Science and Technology(B)》 2014年第3期188-194,共7页
Application of inorganic fertilizers improves crop yields but costs and adverse health effects often discourage their applications. This study therefore aims at evaluating the combined effects of cassava peel compost ... Application of inorganic fertilizers improves crop yields but costs and adverse health effects often discourage their applications. This study therefore aims at evaluating the combined effects of cassava peel compost with poultry manure and mineral fertilizer on growth and yields of Corchorus olitorius. Pots (factorial laid out in a randomized complete block design) and field (split-plot with fertilizer being the main effect and the varieties the sub plot effect) experiments were carried out during rainy season at Ibadan, Nigeria. Treatments consisted of 0, 5, l0 and 20 t/ha composts prepared from cassava peel and poultry manure in ratio 3:1 and mineral fertilizer (NPK 15:15:15) at the rate of 250 kg/ha, using two varieties of C. olitorius. Five and six weeks after planting (WAP), plants were assessed for growth and yields in pot and field experiments respectively, and also in residual studies. Application of compost significantly improved growth (heights) (36.50-41.56 cm), while morphological and dry weight values increased with increase in compost. Marketable yield increase of 13.2%, 22.3%, 32.1% and 29.3% were recorded using 5, 10, 20 t/ha compost and NPK fertilizer respectively in the field. Corresponding increase when ratooned were 40.0%, 42.9%, 57.1% and 52.0%, respectively. Application of compost at the rate of 20 t/ha performed better in the main and residual effect experiments compared to NPK fertilizer and other compost rates. Application of cassavas peels compost at the rate of 20 t/ha proved to be adequate for optimum growth and yield performance of C. olitorius. 展开更多
关键词 Corchorus olitorius COMPOST mineral fertilizer residual effect yield.
下载PDF
Simulation of Fatigue Stiffness Degradation in Prestressed Concrete Beams under Cyclic Loading
16
作者 Junqing Lei Shanshan Cao +1 位作者 Guoshan Xu Yun Xiao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第1期67-74,共8页
In order to investigate and research the fatigue cracking of prestressed concrete fatigue properties and loading and stiffness degeneration process,cyclic loading tests were carried out on six prestressed concrete bea... In order to investigate and research the fatigue cracking of prestressed concrete fatigue properties and loading and stiffness degeneration process,cyclic loading tests were carried out on six prestressed concrete beams and the stiffness degradation under fatigue was investigated. A simulation model of stiffness degradation is proposed based on the stiffness analysis of the fatigue-damaged section. The elastic modulus of damaged concrete and the effective residual area of steel were introduced as well as an adjusted three-stage concrete fatigue damage evolution model. The strip method was used to analyze concrete damage due to changing stress along the depth of the beam section. The simulation and test results were compared and a method of predicting fatigue deflection was presented based on the simulation model. The predicted results were compared with that of the neural network method. It is in good agreement for the simulation results with the test results. It is only less than5% error for the simulation model which can reveal the two-stage degradation of prestressed concrete beams under cyclic loading. It is more precise for the simulation prediction method under proper conditions. 展开更多
关键词 prestressed concrete beam FATIGUE stiffness degradation simulation damaged concrete elastic modulus steel effective residual area deflection prediction
下载PDF
Efficiency of soil-applied ^(67)Zn-enriched fertiliser across three consecutive crops
17
作者 Edson M.MATTIELLO Eduardo L.CANCELLIER +3 位作者 Rodrigo C.DA SILVA Fien DEGRYSE Roslyn BAIRD Mike J.MCLAUGHLIN 《Pedosphere》 SCIE CAS CSCD 2021年第4期531-537,共7页
A very small amount of applied zinc(Zn) is taken up by crops, resulting in low recovery by plants. Adding elemental sulphur to zinc oxide(ZnO) fertiliser could improve Zn solubilisation and exert a higher residual eff... A very small amount of applied zinc(Zn) is taken up by crops, resulting in low recovery by plants. Adding elemental sulphur to zinc oxide(ZnO) fertiliser could improve Zn solubilisation and exert a higher residual effect on crops than soluble Zn sources. We produced an isotopically labelled Zn-elemental sulphur fertiliser and evaluated its performance in comparison to traditional Zn sources during sequential crop cultivation. Three ^(67)Zn-labelled fertilisers,ZnO, zinc sulphate(ZnSO_(4)), and ZnO co-granulated with elemental sulphur(ZnOS^(0)), were soil applied, and their contributions to the uptake of Zn by three consecutive crops, wheat, ryegrass, and corn, were assessed in a 294-d pot experiment. The contributions of Zn fertilisers followed the order: ZnSO_(4) > ZnO= ZnOS^(0). The relative contributions of Zn fertilisers were lower in the first crop than in the subsequent crops. The overall recovery of applied Zn by the three crops was higher for ZnSO_(4) than for ZnO and ZnOS^(0), reaching 1.56%, 0.45%, and 0.33% of the applied Zn, respectively. Zinc recovery by plants was very low, regardless of the source of Zn. Adding elemental sulphur to ZnO did not increase its effectiveness up to 294 d after application. Fertiliser contribution was higher for the subsequent crops than for the initial crop, indicating the importance of assessing the residual effects of Zn fertilisers. 展开更多
关键词 agronomic biofortification elemental sulphur fertilizer residual effect plant uptake Zn bioavailability Zn fertilization Zn source
原文传递
A unifying approach in simulating the shot peening process using a 3D random representative volume finite element model 被引量:13
18
作者 Dianyin HU Ye GAO +4 位作者 Fanchao MENG Jun SONG Yanfei WANG Mengxi REN Rongqiao WANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第4期1592-1602,共11页
Using a modified 3D random representative volume(RV)finite element model,the effects of model dimensions(impact region and interval between impact and representative regions),model shapes(rectangular,square,and c... Using a modified 3D random representative volume(RV)finite element model,the effects of model dimensions(impact region and interval between impact and representative regions),model shapes(rectangular,square,and circular),and peening-induced thermal softening on resultant critical quantities(residual stress,Almen intensity,coverage,and arc height)after shot peening are systematically examined.A new quantity,i.e.,the interval between impact and representative regions,is introduced and its optimal value is first determined to eliminate any boundary effect on shot peening results.Then,model dimensions are respectively assessed for all model shapes to reflect the actual shot peening process,based on which shape-independent critical shot peening quantities are obtained.Further,it is found that thermal softening of the target material due to shot peening leads to variances of the surface residual stress and arc height,demonstrating the necessity of considering the thermal effect in a constitutive material model of shot peeing.Our study clarifies some of the finite element modeling aspects and lays the ground for accurate modeling of the SP process. 展开更多
关键词 Almen intensity Boundary effect Finite element modeling residual stress Shot peening
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部