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Grain-filling strategies of wheat of contrasting grain sizes under various planting patterns and irrigation levels
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作者 Zimeng Liang Jingyi Feng +4 位作者 Jiayu Li Yangyang Tang Tiankang He Vinay Nangia Yang Liu 《The Crop Journal》 SCIE CSCD 2024年第3期897-906,共10页
In a study comparing grain filling and yield in a large-and a small-grain-size wheat cultivar under two planting patterns and two irrigation regimes,plastic-covered ridge and furrow planting with sprinkler irrigation ... In a study comparing grain filling and yield in a large-and a small-grain-size wheat cultivar under two planting patterns and two irrigation regimes,plastic-covered ridge and furrow planting with sprinkler irrigation increased grain filling and yield in both cultivars.The largest contributors to grain yield were an extended active grain-filling period in Shuangda 1 and an increased mean grain-filling rate in XN538. 展开更多
关键词 Plastic-covered ridge and furrow cultivation Sprinkler irrigation WHEAT Grain size Grain filling
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Effects of Different Seed Stem Sizes on the Changes of Available Elements in Rhizosphere Soil of Fritillaria thunbergii Miq.
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作者 Yong PENG Rui PAN +3 位作者 Zhengyan LIU Xiaohong WU Nong ZHOU Wenwu YANG 《Agricultural Biotechnology》 2024年第3期18-23,共6页
[Objectives]This study was conducted to screen suitable seed stems of Fritillaria thunbergii Miq.from different provenances and to provide a theoretical basis for the high-yielding and high-efficiency cultivation of F... [Objectives]This study was conducted to screen suitable seed stems of Fritillaria thunbergii Miq.from different provenances and to provide a theoretical basis for the high-yielding and high-efficiency cultivation of F.thunbergii Miq.introduced to different places.[Methods]F.thunbergii Miq.from four different provenances including Zhejiang,Nantong and Chongqing were introduced and cultivated in Wanzhou of Chongqing.The contents of available Zn,Fe,Mn,Cu,Mo,N,P,K,Ca and Mg in rhizosphere soil of F.thunbergii Miq.during five growing stages were determined after selecting different stem sizes for field cultivation.[Results]Small stems of Pan an and Ningbo provenances(SSG3,121-160/kg)and middle stems of Nantong and Fengjie provenances(SSG2,81-120/kg)showed higher soil availability.[Conclusions]In the process of introduction and cultivation of F.thunbergii Miq.,high yield and high efficiency can be achieved by selecting smaller seed stems of F.thunbergii Miq. 展开更多
关键词 Fritillaria thunbergii Miq. Different provenances Stem size INTRODUCTION CULTIVATION Soil nutrient element AVAILABILITY
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Analysis of a landfill cover without geomembrane using varied particle sizes of recycled concrete 被引量:2
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作者 Charles Wang Wai Ng Cheuk Lam Ng +4 位作者 Junjun Ni Haowen Guo Qi Zhang Qiang Xue Rui Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第5期1263-1273,共11页
Previous studies have demonstrated the effectiveness of a novel three-layer landfill cover system constructed with recycled concrete aggregates(RCAs)without geomembrane in both laboratory and field.However,no systemat... Previous studies have demonstrated the effectiveness of a novel three-layer landfill cover system constructed with recycled concrete aggregates(RCAs)without geomembrane in both laboratory and field.However,no systematic investigation has been carried out to optimize the combination of the particle sizes for fine-grained RCAs(FRC)and coarse-grained RCAs(CRC)that can be used for the three-layer landfill cover system.The aim of this paper is to assist engineers in designing the three-layer landfill cover system under a rainfall of 100-year return period in humid climate conditions using an easily controlled soil parameter D10 of RCAs.The numerical study reveals that when D10 of FRC increases from 0.05 mm to 0.16 mm,its saturated permeability increases by 10 times.As a result,a larger amount of rainwater infiltrates into the cover system,causing a higher lateral diversion in both the top FRC and middle CRC layers.No further changes in the lateral diversion are observed when the D10 value of FRC is larger than 0.16 mm.Both the particle sizes of FRC and CRC layers are shown to have a minor influence on the percolation under the extreme rainfall event.This implies that the selection of particle sizes for the FRC and CRC layers can be based on the availability of materials.Although it is well known that the bottom layer of the cover system should be constructed with very fine-grained soils if possible,this study provides an upper limit to the particle size that can be used in the bottom layer(D10 not larger than 0.02 mm).With this limit,the three-layer system can still minimize the water percolation to meet the design criterion(30 mm/yr)even under a 100-year return period of rainfall in humid climates. 展开更多
关键词 Capillary barrier Landfill cover Particle size Recycled concrete
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Arc erosion behaviors of AgSnO_2 contact materials prepared with different SnO_2 particle sizes 被引量:10
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作者 张苗 王献辉 +2 位作者 杨晓红 邹军涛 梁淑华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第3期783-790,共8页
To clarify the effect of SnO2 particle size on the arc erosion behavior of AgSnO2 contact material, Ag?4%SnO2 (mass fraction) contact materials with different sizes of SnO2 particles were fabricated by powder metallur... To clarify the effect of SnO2 particle size on the arc erosion behavior of AgSnO2 contact material, Ag?4%SnO2 (mass fraction) contact materials with different sizes of SnO2 particles were fabricated by powder metallurgy. The microstructure of Ag?4%SnO2 contact materials was characterized, and the relative density, hardness and electrical conductivity were measured. The arc erosion of Ag?4%SnO2 contact materials was tested, the arc duration and mass loss before and after arc erosion were determined, the surface morphologies and compositions of Ag?4%SnO2 contact materials after arc erosion were characterized, and the arc erosion mechanism of AgSnO2 contact materials was discussed. The results show that fine SnO2 particle is beneficial for the improvement of the relative density and hardness, but decreases the electrical conductivity. With the decrease of SnO2 particle size, Ag?4%SnO2contact material presents shorter arc duration, less mass loss, larger erosion area and shallower arc erosion pits. 展开更多
关键词 AgSnO_2 contact materials SnO_2 particle size arc erosion electrical conductivity HARDNESS
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An Organic Solvent-Assisted Intercalation and Collection (OAIC) for Ti_(3)C_(2)T_(x) MXene with Controllable Sizes and Improved Yield 被引量:4
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作者 Danyao Qu Yingying Jian +11 位作者 Lihao Guo Chen Su Ning Tang Xingmao Zhang Wenwen Hu Zheng Wang Zhenhuan Zhao Peng Zhong Peipei Li Tao Du Hossam Haick Weiwei Wu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第11期428-440,共13页
A good method of synthesizing Ti_(3)C_(2)T_(x)(MXene)is critical for ensuring its success in practical applications,e.g.,electromagnetic interference shielding,electrochemical energy storage,catalysis,sensors,and biom... A good method of synthesizing Ti_(3)C_(2)T_(x)(MXene)is critical for ensuring its success in practical applications,e.g.,electromagnetic interference shielding,electrochemical energy storage,catalysis,sensors,and biomedicine.The main concerns focus on the moderation of the approach,yield,and product quality.Herein,a modified approach,organic solvent-assisted intercalation and collection,was developed to prepare Ti_(3)C_(2)T_(x) flakes.The new approach simultaneously solves all the concerns,featuring a low requirement for facility(centrifugation speed<4000 rpm in whole process),gram-level preparation with remarkable yield(46.3%),a good electrical conductivity(8672 S cm^(−1)),an outstanding capacitive performance(352 F g^(−1)),and easy control over the dimension of Ti_(3)C_(2)T_(x) flakes(0.47–4.60μm^(2)).This approach not only gives a superb example for the synthesis of other MXene materials in laboratory,but sheds new light for the future mass production of Ti_(3)C_(2)T_(x) MXene. 展开更多
关键词 Two-dimensional materials MXenes Controllable sizes High yield
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Model of homogenisation for analysing the effect of micrometre pore sizes on the elastic moduli of porous materials 被引量:2
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作者 A.F.Fedotov 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第5期1060-1066,共7页
A homogenisation model for analysing the effect of micrometre pore sizes on the engineering moduli of elasticity of porous materials was proposed.In the proposed model,the engineering coefficients of localization of t... A homogenisation model for analysing the effect of micrometre pore sizes on the engineering moduli of elasticity of porous materials was proposed.In the proposed model,the engineering coefficients of localization of total strains(LTS coefficients)are considered instead of the classical strain localization tensors.For a pore,these coefficients represent the ratio of the sum of the strains in the volume of the pore to the sum of the strains in the volume of the porous body.To estimate the elastic moduli of a material with an arbitrary pore size,it is sufficient to have information about the elastic moduli and the LTS coefficient of a material with one basic pore size.Then,in Eshelby's model of equivalent inclusion,a transition to LTS coefficient for material with arbitrary pore size is achieved,and its elasticity moduli are determined.The results for Young's modulus of porous titanium,with different sizes of spherical pores,completely conform with the experimental data.We have obtained a model theoretic estimate of the upper bounds of Young's modulus of porous materials with infinitely small pore size.For the spherical pores,the proposed assessment coincides with the upper limits of the Hashin-Shtrikman bounds. 展开更多
关键词 Elastic MODULI POROUS material PORE sizes
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AHP-Based Optimal Selection of Garment Sizes for Online Shopping 被引量:2
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作者 许轶超 齐洁 丁永生 《Journal of Donghua University(English Edition)》 EI CAS 2007年第2期222-225,共4页
Garment online shopping has been accepted by more and more consumers in recent years. In online shopping, a buyer only chooses the garment size judged by his own experience without trying-on, so the selected garment m... Garment online shopping has been accepted by more and more consumers in recent years. In online shopping, a buyer only chooses the garment size judged by his own experience without trying-on, so the selected garment may not be the fittest one for the buyer due to the variety of body's figures. Thus, we propose a method of optimal selection of garment sizes for online shopping based on Analytic Hierarchy Process (AHP). The hierarchical structure model for optimal selection of garment sizes is structured and the fittest garment for a buyer is found by calculating the matching degrees between individual's measurements and the corresponding key-part values of ready-to-wear clothing sizes. In order to demonstrate its feasibility, we provide an example of selecting the fittest sizes of men's bottom. The result shows that the proposed method is useful in online clothing sales application. 展开更多
关键词 optimal selection of garment sizes analytichierarchy process apparel online shopping
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Effects of Ru nanoparticle sizes confined in cavities of SBA-16 on the catalytic performance of Fischer-Tropsch synthesis reaction 被引量:1
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作者 Jian Chen Jinlin Li +2 位作者 Yanxi Zhao Yuhua Zhang Jingping Hong 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第6期673-679,共7页
Ru nanoparticles with different sizes confined in the cavities of mesoporous SBA-16 have been successfully synthesized by incipient wetness impregnation method with a Ru loading of 4 wt%. The catalysts were characteri... Ru nanoparticles with different sizes confined in the cavities of mesoporous SBA-16 have been successfully synthesized by incipient wetness impregnation method with a Ru loading of 4 wt%. The catalysts were characterized by XRD, N2 adsorption-desorption, H2-TPR, H2-TPD, O2-titration and TEM. The catalytic performance of Fischer-Tropsch synthesis over the catalyst was tested in a fixed-bed reactor. The addition of citric acid in the impregnation procedure shows a significant influence on the size of Ru nanoparticles. The selectivity to C5+ increases, while the selectivities to methane and C2-C4 light hydrocarbons decrease with Ru average particles size from 2.0 nm to 9.3 nm, . The Ru catalyst confined in the SBA-16 with average nanoparticle size of 5.3 nm gives the best activity. 展开更多
关键词 Fischer-Tropsch synthesis Ru catalyst SBA-16 particle sizes
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The Sizes of Sitophilus zeamais in Different Life Stage 被引量:1
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作者 JI Le WANG Dianxuan +2 位作者 ZHAO Chao ZHANG Ruijie ZENG Fangfang 《Grain & Oil Science and Technology》 2018年第4期163-170,共8页
Knowing the developmental states of stored grain insects, especially for the immature stages hidden in cereal kernel, such as Sitophilus zeamais, could be in favor of monitoring early and controlling effectively. Atla... Knowing the developmental states of stored grain insects, especially for the immature stages hidden in cereal kernel, such as Sitophilus zeamais, could be in favor of monitoring early and controlling effectively. Atlas and scale parameters on different developmental stages of S. zeamais in wheat kernel were captured and described by three-dimensional microscope of super depth of field observation. The four instars of larva, pre-pupa, pupa, new adult, old adult in kernel could be seen by dissecting the infested kernels. The length, height, and width of larva body increased with insect development and centralized the sizes corresponding to the four instars of larva. The length of larva body centralized near 554, 746, 1 462, and 2 147 μm. The height of larva body centralized about 388, 575, 847, and 1 651 μm. The width of larva body centralized near 340, 598, 798, and 1 568 μm. Head capsule width was in same size for each exuviating period, centralized near 203, 317, 535, and 603 μm, and got big sharply with the instar changed. Developmental duration of four larva instars was about 21 days reared in wheat, less than 28 days reared in maize as published. The atlas and description should be helpful for monitoring the S. zeamais development hidden in cereal kernels and designing control strategy. 展开更多
关键词 MAIZE WEEVIL IMMATURE STAGES MORPHOLOGY Life STAGES sizes
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Average cluster sizes and cluster size distributions of superfine nickel particles in light media
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作者 李敬生 杜飞虎 王娟 《Journal of Central South University》 SCIE EI CAS 2009年第3期399-404,共6页
Effects of shear rates on average cluster sizes (ACSs) and cluster size distributions (CSDs) in uni- and bi-systems of partly charged superfine nickel particles were investigated by Brownian dynamics, and clustering p... Effects of shear rates on average cluster sizes (ACSs) and cluster size distributions (CSDs) in uni- and bi-systems of partly charged superfine nickel particles were investigated by Brownian dynamics, and clustering properties in these systems were compared with those in non-polar systems. The results show that the ACSs in bi-polar systems are larger than those in the non-polar systems. In uni-polar systems the behavior of clustering property differs: at the lower ionic concentration (10%), repulsive force is not strong enough to break clusters, but may greatly weaken them. The clusters are eventually cracked into smaller ones only when concentration of uni-polar charged particles is large enough. In this work, the ionic concentration is 20%. The relationship between ACS and shear rates follows power law in a exponent range of 0.176-0.276. This range is in a good agreement with the range of experimental data, but it is biased towards the lower limit slightly. 展开更多
关键词 ionic concentration average cluster sizes cluster size distribution power law
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Influence of parental sample sizes on the estimating genetic parameters in cultured clam Meretrix meretrix based on factorial mating designs
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作者 LIANG Bingbing YUE Xin +1 位作者 WANG Hongxia LIU Baozhong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第6期42-49,共8页
The precise and accurate knowledge of genetic parameters is a prerequisite for making efficient selection strategies in breeding programs.A number of estimators of heritability about important economic traits in many ... The precise and accurate knowledge of genetic parameters is a prerequisite for making efficient selection strategies in breeding programs.A number of estimators of heritability about important economic traits in many marine mollusks are available in the literature,however very few research have evaluated about the accuracy of genetic parameters estimated with different family structures.Thus,in the present study,the effect of parent sample size for estimating the precision of genetic parameters of four growth traits in clam M.meretrix by factorial designs were analyzed through restricted maximum likelihood(REML) and Bayesian.The results showed that the average estimated heritabilities of growth traits obtained from REML were 0.23-0.32 for 9 and 16 full-sib families and 0.19-0.22 for 25 full-sib families.When using Bayesian inference,the average estimated heritabilities were0.11-0.12 for 9 and 16 full-sib families and 0.13-0.16 for 25 full-sib families.Compared with REML,Bayesian got lower heritabilities,but still remained at a medium level.When the number of parents increased from 6 to 10,the estimated heritabilities were more closed to 0.20 in REML and 0.12 in Bayesian inference.Genetic correlations among traits were positive and high and had no significant difference between different sizes of designs.The accuracies of estimated breeding values from the 9 and 16 families were less precise than those from 25 families.Our results provide a basic genetic evaluation for growth traits and should be useful for the design and operation of a practical selective breeding program in the clam M.meretrix. 展开更多
关键词 Meretrix meretrix parental sample sizes genetic parameter factorial design restricted maximum likelihood Bayesian inference
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An Artificial Neural Network for Estimating Sizes of Spot Welding Nuggets
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作者 张忠典 李严 +1 位作者 何幸平 吴林 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第2期94-98,共5页
Sizes of nuggets are often used to evaluate spot weld quality in production. This paper presents a neural estimator used to carry out non-destructive on-line analysis of spot weld quality in which trained ANN function... Sizes of nuggets are often used to evaluate spot weld quality in production. This paper presents a neural estimator used to carry out non-destructive on-line analysis of spot weld quality in which trained ANN functions to map dynamic resistance characteristics into sizes of spot weld nuggets and results confirm the validity of neural network for this type of application. 展开更多
关键词 Artificial neural network(ANN) SPOT welding sizes of NUGGETS ESTIMATING
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FLOWING FILM JIGGING FUNCTION IN THE NEW″IFFC″PROCESS FOR SEPARATING MINERALS OF ULTRAFINE SIZES
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作者 Lu,Yongxin Beijing General Research Institute of Mining and Metallurgy,Beijing 100044,China 《中国有色金属学会会刊:英文版》 CSCD 1993年第2期22-26,40,共6页
The concept of the flowing film jigging was first applied to the flowing film concentration area.The flowingfilm jigging function is an important element of the new process,in jection-flowing film centrifugation(IFFC)... The concept of the flowing film jigging was first applied to the flowing film concentration area.The flowingfilm jigging function is an important element of the new process,in jection-flowing film centrifugation(IFFC),for separating and recovering minerals of ultrafine sizes. 展开更多
关键词 flowing FILM JIGGING mineral processing ULTRAFINE sizes IFFC
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X-RAY MEASUREMENT OF THE GRAIN SIZES OF WSi_(2) FORMED IN COSPUTTERED W-Si FILMS
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作者 JIANG Xiaoming HUANG Yonglan +1 位作者 WU Ziqin LI Bingzong 《Chinese Physics Letters》 SCIE CAS 1986年第12期569-572,共4页
The broadening of X-ray diffraction peaks has been used successfully to measure the grain sizes of WSi_(2) in cosputtered W-Si films after annealing.The grain size of WSi_(2) increases with annealing temperature and r... The broadening of X-ray diffraction peaks has been used successfully to measure the grain sizes of WSi_(2) in cosputtered W-Si films after annealing.The grain size of WSi_(2) increases with annealing temperature and reaches 115nm after annealing at 1000°C.The grain sizes are quite similar to that obtained by transmission electron microscope in electron beam coevaporated film and low pressure chemical vapor deposited film. 展开更多
关键词 sizes GRAIN annealing.
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Effects of Some Additives on the Adhesion of Polyacrylamide Sizes to Fibers
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作者 祝志峰 雷良 《Journal of Donghua University(English Edition)》 EI CAS 2006年第4期21-25,共5页
The influences of some additives such as dissolving promoters, plasticizers and molecular stabilizers of polyacryiamide sizes on the adhesion of the sizes to polyester and cotton fibers were investigated for warp sizi... The influences of some additives such as dissolving promoters, plasticizers and molecular stabilizers of polyacryiamide sizes on the adhesion of the sizes to polyester and cotton fibers were investigated for warp sizing. The additives evaluated included glycerine, sodium sulfate, sodium nitrite, urea, thiourea, and sodium dodecyl benzene sulfonate. By an impregnated roving method, the adhesion was evaluated in terms of the maximum strength and work to break of slightly sized roving. The polyacrylamide used was prepared through solution polymerization by free radical initiator. It was found that the variation in the adhesion depends not only on the type and amount of additives, but also on the fibers to be glued, Some additives improve the adhesion while others can not. To enhance the adhesion, sodium sulfate is superior to urea or sodium dodecyl benzene sulfonate as dissolving promoters; sodium nitrite is better than urea as plasticizers~ and glycerine is favorable to urea and thiourea as molecule stabilizer. Moreover, the experimental results arc also discussed and analyzed from the viewpoint of adhesion theory, especially in accordance with the weak boundary layer and internal stress on the interfaces of fiber-adhesive layer. 展开更多
关键词 POLYACRYLAMIDE warp sizes ADHESION fibers.
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Determination of Particle Sizes and Crystalline Phases on Colloidal Silicon Nanoparticle Suspensions
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作者 S.M. Scholz and H Hofmann(Powder Technology Laboratory, Department of Materials Science, Swiss Federal Institiute of Technology Lausanne,CH-1015 Lausanne, Switzerland) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第6期548-550,共3页
Particle size and crystallinity of silicon nanoparticles were determined by analyzing the optical extinction spectra of colloidal suspensions. Experimental results from these colloids were anaiyzed using Mie theory in... Particle size and crystallinity of silicon nanoparticles were determined by analyzing the optical extinction spectra of colloidal suspensions. Experimental results from these colloids were anaiyzed using Mie theory in connection with effective medium theory, in order to determine particle sizes and their internal structure with the simple technique of optical transmission spectroscopy. By modeling an effective refractive index for the particles, the crystalline volume fraction can be extracted from extinction spectra in addition to information about the size. The crystalline volume fraction determined in this way were used to calibrate the ratio of the Raman cross sections for nanocrystalline and amorphous silicon, which was found to be σc./σa = 0.66 展开更多
关键词 Determination of Particle sizes and Crystalline Phases on Colloidal Silicon Nanoparticle Suspensions
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Effect of proteins,polysaccharides,and particle sizes on sludge dewaterability 被引量:37
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作者 SHAO Liming,HE Peipei,YU Guanghui,HE Pinjing State Key Laboratory of Pollution Control and Resources Reuse,Key Laboratory of Yangtze River Water Environment,College of Environmental Science and Engineering,Tongji University,Shanghai 200092,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第1期83-88,共6页
Four batch experiments of hydrolysis and acidification were carried out to investigate the distributions of proteins (PN) and polysaccharides (PS) in the sludge, the PN/PS ratio, the particle sizes, and their rela... Four batch experiments of hydrolysis and acidification were carried out to investigate the distributions of proteins (PN) and polysaccharides (PS) in the sludge, the PN/PS ratio, the particle sizes, and their relationship with sludge dewaterability (as determined by capillary suction time, CST). The sludge flocs were stratified through centrifugation- and ultrasound-based method into four fractions: (1) slime, (2) loosely bound extracellular polymeric substances (LB-EPS), (3) tightly bound EPS (TB-EPS), and (4) pellet. The results showed that PN was mainly partitioned in the pellet (80.7%) and TB-EPS (9.6%) fractions, while PS distributed evenly in the four fractions. During hydrolysis and acidification, PN was transferred from the pellet and TB-EPS fractions to the slime fraction, but PS had no significant transfer trends. The mean particle sizes of the sludge flocs decreased with hydrolysis and acidification. The pH had a more significant influence on the dewaterability of sludge flocs than temperature. Sludge dewaterability during hydrolysis and acidification processes greatly deteriorated from 9.7 s at raw sludge to 340-450 s under alkaline conditions. However, it was just slightly increased under acidic conditions. Further investigation suggested that CST was affected by soluble PN, soluble PN/PS, and particle sizes of sludge flocs, but was affected slightly by total PN, PS, or PN/PS in the whole sludge flocs and other fractions (except slime). 展开更多
关键词 DEWATERABILITY extracellular polymeric substances particle size POLYSACCHARIDES PROTEINS sewage sludge
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Leaching behavior of V,Pb,Cd,Cr,and As from stone coal waste rock with different particle sizes 被引量:10
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作者 Ying-bo Dong Yue Liu Hai Lin 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第8期861-870,共10页
This paper investigates the leaching behavior of heavy metals(V,Pb,Cd,Cr,and As) from stone coal waste rocks with various particle sizes using dynamic leaching experiments.The results show that the dissolved concentra... This paper investigates the leaching behavior of heavy metals(V,Pb,Cd,Cr,and As) from stone coal waste rocks with various particle sizes using dynamic leaching experiments.The results show that the dissolved concentrations of V and As initially increased and then slightly decreased as time progressed and that the dissolved concentrations of Pb,Cd,and Cr were high in the early stage before decreasing.The particle size of the stone coal waste rocks strongly influenced the heavy metal concentration in the leaching solutions.The effects of the particle size of the stone coal waste rocks on the dissolved concentrations of V,Pb,and As decreased in the order fine fraction > medium fraction > coarse fraction,and the effects of particle size on the dissolved concentrations of Cr and Cd decreased in the order medium fraction > coarse fraction > fine fraction and coarse fraction > medium fraction > fine fraction,respectively.The quantities of heavy metals dissolved from the stone coal waste rock with fine particle sizes were observed to decrease in the order V(17104.36 μg/kg) > As(609.41 μg/kg) > Pb(469.24 μg/kg) > Cr(56.35 μg/kg) > Cd(27.52 μg/kg),and the dissolution rates decreased in the order As(2.96%) > Pb(0.93%) > V(0.35%) > Cd(0.25%) > Cr(0.01%).The specific surface area,pore size of the stone coal waste rocks,and chemical forms of heavy metals also influenced the release of heavy metals from the stone coal waste rocks.Kinetic analysis showed that the dissolution of heavy metals fundamentally agreed with the rate equation controlled by the shrinking core model.The results of this study are expected to serve as a reference for the evaluation of heavy metals contamination from stone coal waste rocks. 展开更多
关键词 STONE COAL WASTE ROCKS HEAVY metal LEACHING behavior dynamic LEACHING test particle size
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Kinetics of oxidation roasting of molybdenite with different particle sizes 被引量:7
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作者 Xiao-bin LI Tao WU +3 位作者 Qiu-sheng ZHOU Tian-gui QI Zhi-hong PENG Gui-hua LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第3期842-852,共11页
The kinetics of oxidation roasting of molybdenum concentrate was studied by differential thermal−gravimetric experiments and non-isothermal analysis methods.The results show that high temperature is beneficial for oxi... The kinetics of oxidation roasting of molybdenum concentrate was studied by differential thermal−gravimetric experiments and non-isothermal analysis methods.The results show that high temperature is beneficial for oxidation of molybdenum concentrate.The initial oxidation temperature of the molybdenum concentrate is 450℃,and the rapid oxidation occurs above 500℃.The oxidation process conforms to the unreacted shrinking nucleus model.The early stage of the oxidation is controlled by chemical reaction with the apparent activation energy of 123.180 kJ/mol,while the later stage is controlled by internal diffusion with the apparent activation energy of 80.175 kJ/mol.Moreover,the oxidation rate is closely related to particle size of the concentrate.The smaller the particle size is,the larger the oxidation rate is. 展开更多
关键词 MOLYBDENITE OXIDATION ROASTING KINETICS particle size
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Diversity of intergranular corrosion and stress corrosion cracking for 5083 Al alloy with different grain sizes 被引量:10
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作者 Jin QIN Zhi LI +2 位作者 Ming-yang MA Dan-qing YI Bin WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第3期765-777,共13页
5083 Al alloy sheets with different grain sizes(8.7-79.2 μm) were obtained by cold rolling and annealing. Their microstructures, intergranular corrosion(IGC), stress corrosion cracking(SCC), and crack propagation beh... 5083 Al alloy sheets with different grain sizes(8.7-79.2 μm) were obtained by cold rolling and annealing. Their microstructures, intergranular corrosion(IGC), stress corrosion cracking(SCC), and crack propagation behaviors were investigated. The results showed that samples with coarse grains exhibit better IGC resistance with a corrosion depth of 15 μm. The slow strain rate test results revealed that fine-grained samples exhibit better SCC resistance with a susceptibility index(ISSRT) of 11.2%. Furthermore, based on the crack propagation mechanism, grain refinement can improve the SCC resistance by increasing the number of grain boundaries to induce the corrosion crack propagation along a tortuous path. The grains with {011} orientation could hinder crack propagation by orientating it toward the low-angle grain boundary region. The crack in the fine-grained material slowly propagates due to the tortuous path, and low H;and Cl;concentrations. 展开更多
关键词 grain size intergranular corrosion stress corrosion cracking crack propagation 5083 Al alloy
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