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Wetting alternating with partial drying during grain filling increases lysine biosynthesis in inferior rice grain
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作者 Yi Jiang Wenli Tao +2 位作者 Weiyang Zhang Zhiqin Wang Jianchang Yang 《The Crop Journal》 SCIE CSCD 2024年第1期262-270,共9页
Lysine content is a criterion of the nutritional quality of rice.Understanding the process of lysine biosynthesis in early-flowering superior grain(SG)and late-flowering inferior grain(IG)of rice would advance breedin... Lysine content is a criterion of the nutritional quality of rice.Understanding the process of lysine biosynthesis in early-flowering superior grain(SG)and late-flowering inferior grain(IG)of rice would advance breeding and cultivation to improve nutritional quality.However,little information is available on differences in lysine anabolism between SG and IG and the underlying mechanism,and whether and how irrigation regimes affect lysine anabolism in these grains.A japonica rice cultivar was grown in the field and two irrigation regimes,continuous flooding(CF)and wetting alternating with partial drying(WAPD),were imposed from heading to the mature stage.Lysine content and activities of key enzymes of lysine biosynthesis,and levels of brassinosteroids(BRs)were lower in the IG than in the SG at the early grainfilling stage but higher at middle and late grain-filling stages.WAPD increased activities of these key enzymes,BR levels,and contents of lysine and total amino acids in IG,but not SG relative to CF.Application of 2,4-epibrassinolide to rice panicles in CF during early grain filling reproduced the effects of WAPD,but neither treatment altered the activities of enzymes responsible for lysine catabolism in either SG or IG.WAPD and elevated BR levels during grain filling increased lysine biosynthesis in IG.Improvement in lysine biosynthesis in rice should focus on IG. 展开更多
关键词 BRASSINOSTEROIDS Inferior grain Lysine biosynthesis Rice Wetting alternating with partial drying
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Effect of different drying methods on the amino acids,α-dicarbonyls and volatile compounds of rape bee pollen 被引量:1
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作者 Yanxiang Bi Jiabao Ni +6 位作者 Xiaofeng Xue Zidan Zhou Wenli Tian Valérie Orsat Sha Yan Wenjun Peng Xiaoming Fang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期517-527,共11页
The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed ... The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed vacuum drying(PVD),freeze drying(FD),infrared drying(IRD),hot-air drying(HAD)and sun drying(SD)on free amino acids(FAAs),α-dicarbonyl compounds(α-DCs)and volatile compounds(VOCs)in rape bee pollen(RBP)were determined.The results showed that FD significantly released the essential amino acids(EAAs)compared with fresh samples while SD caused the highest loss.Glucosone was the dominantα-DCs in RBP and the highest loss was observed after PVD.Aldehydes were the dominant volatiles of RBP and SD samples contained more new volatile substances(especially aldehydes)than the other four drying methods.Comprehensively,FD and PVD would be potential methods to effectively reduce the quality deterioration of RBP in the drying process. 展开更多
关键词 drying Bee pollen Free amino acids α-Dicarbonyl compounds Volatile compounds
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Asymmetric Drying and Wetting Trends in Eastern and Western China 被引量:1
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作者 Wen WU Fei JI +1 位作者 Shujuan HU Yongli HE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期221-232,共12页
As an important factor that directly affects agricultural production, the social economy, and policy implementation,observed changes in dry/wet conditions have become a matter of widespread concern. However, previous ... As an important factor that directly affects agricultural production, the social economy, and policy implementation,observed changes in dry/wet conditions have become a matter of widespread concern. However, previous research has mainly focused on the long-term linear changes of dry/wet conditions, while the detection and evolution of the non-linear trends related to dry/wet changes have received less attention. The non-linear trends of the annual aridity index, obtained by the Ensemble Empirical Mode Decomposition(EEMD) method, reveal that changes in dry/wet conditions in China are asymmetric and can be characterized by contrasting features in both time and space in China. Spatially, most areas in western China have experienced transitions from drying to wetting, while opposite changes have occurred in most areas of eastern China. Temporally, the transitions occurred earlier in western China compared to eastern China. Research into the asymmetric spatial characteristics of dry/wet conditions compensates for the inadequacies of previous studies, which focused solely on temporal evolution;at the same time, it remedies the inadequacies of traditional research on linear trends over centennial timescales. Analyzing the non-linear trend also provides for a more comprehensive understanding of the drying/wetting changes in China. 展开更多
关键词 aridity index EEMD dry/wet conditions asymmetric evolution
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Effect of drying cracks on swelling and self-healing of bentonite-sand blocks used as engineered barriers for radioactive waste disposal
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作者 Yu Tan Guangping Zhou +2 位作者 Huyuan Zhang Xiaoya Li Ping Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1776-1787,共12页
Experiments were conducted to evaluate the healing of drying cracks in air-dried bentonite-sand blocks after hydration and swelling in groundwater,providing justifications to simplify the protection of blocks prior to... Experiments were conducted to evaluate the healing of drying cracks in air-dried bentonite-sand blocks after hydration and swelling in groundwater,providing justifications to simplify the protection of blocks prior to installation in a high-level radioactive waste repository.Synthetic groundwater was prepared to represent the geochemistry of Beishan groundwater,and was used to hydrate the blocks during the swelling pressure and swelling strain measurements,as Beishan is the most promising site for China's repository.Healing of the surface cracks was recorded by photography,and healing of the internal cracks was visualized by CT images and hydraulic conductivity of air-dried blocks.The results indicate that the maximum swelling pressure and swelling strain are primarily affected by the geochemistry of Beishan groundwater,but not affected by the drying cracks.The maximum swelling pressure and swelling strain of air-dried blocks are comparable to or even higher than the pressure and strain of fresh blocks.The maximum swelling pressure measured in strong(i.e.high ion strength)Beishan groundwater was 44%of the pressure measured in deionized(DI)water,and the maximum swelling strain was reduced to 23%of the strain measured in DI water.Nevertheless,the remained swelling of the blocks hydrated in strong Beishan groundwater was sufficient to heal the surface and internal drying cracks,as demonstrated by the pictures of surface cracks and CT images.The hydraulic conductivity of the air-dried block permeated with strong groundwater was comparable(3.7×higher)to the hydraulic conductivity of the fresh block,indicating the self-healing of drying cracks after hydration and swelling in groundwater.A simplified method of protecting the block with plastic wraps before installation is recommended,since the remained swelling of the block hydrated in Beishan groundwater is sufficient to heal the drying cracks. 展开更多
关键词 Beishan groundwater chemistry Bentonite buffer drying cracks High-level radioactive waste(HLW) SELF-HEALING SWELLING
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Solvent transport dynamics and its effect on evolution of mechanical properties of nitrocellulose(NC)-based propellants under hot-air drying process
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作者 Enfa Fu Mingjun Yi +1 位作者 Qianling Liu Zhenggang Xiao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期262-270,共9页
Appropriate drying process with optimized controlling of drying parameters plays a vital role in the improvement of the quality and performance of propellant products.However,few research on solvent transport dynamics... Appropriate drying process with optimized controlling of drying parameters plays a vital role in the improvement of the quality and performance of propellant products.However,few research on solvent transport dynamics within NC-based propellants was reported,and its effect on the evolution of mechanical properties was not interpreted yet.This study is conducted to gain a comprehensive understanding of hot-air drying for NC-based propellants and clarify the effect of temperature on solvent transport behavior and further the change of mechanical properties during drying.The drying kinetic curves show the drying time required is decreased but the steady solvent content is increased and the drying rate is obviously increased with the increase of hot-air temperatures,indicating hot-air temperatures have a significant effect on drying kinetics.A modified drying model was established,and results show it is more appropriate to describe solvent transport behavior within NC-based propellants.Moreover,two linear equations were established to exhibit the relationship between solvent content and its effect on the change of tensile properties,and the decrease of residual solvent content causes an obvious increase of tensile strength and tensile modulus of propellant products,indicating its mechanical properties can be partly improved by adjustment of residual solvent content.The outcomes can be used to clarify solvent transport mechanisms and optimize drying process parameters of double-based gun propellants. 展开更多
关键词 Nitrocellulose-based propellants Solvent transport dynamics Mechanical properties drying kinetics Effective solvent diffusion coefficient
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Short Communication: Enhancing the Drying Process of Microbial-Based Products with a Dehumidifier
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作者 Nor Hidayah Bohari Elya Masya Mohd Fishal +2 位作者 Ili Bazilah Abd Razak Muhammad Ashraf Arif Mohd Nasir Cik Mohd Rizuan Zainal Abidin 《Advances in Microbiology》 CAS 2024年第6期333-339,共7页
The development of microbial-based products requires certain criteria for them to be successfully commercialized. The product must meet the following desirable criteria: effectiveness, contamination free, stability, c... The development of microbial-based products requires certain criteria for them to be successfully commercialized. The product must meet the following desirable criteria: effectiveness, contamination free, stability, cost-effectiveness, and a prolonged shelf life. Controlling the drying process is crucial for ensuring the stability and durability of the product. The traditional approach, which involved mechanical and natural drying, led to decreased productivity and quality. The objective of this research endeavour was to achieve a dry process enhancement while preserving the microbial quality of Trichoderma asperellum (M103). The temperature and relative humidity during the drying period were monitored under two conditions: with and without a dehumidifier. The results demonstrate that the dehumidifier increases drying period efficiency by up to 63%. 展开更多
关键词 DEHUMIDIFIER drying Relative Humidity Microbial-Based Product
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Determination of Natural Logarithm of Diffusion Coefficient and Activation Energy of Thin Layer Drying Process of Ginger Rhizome Slices
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作者 Austin Ikechukwu Gbasouzor Sam Nna Omenyi +1 位作者 Sabuj Mallik Jude E. Njoku 《World Journal of Engineering and Technology》 2024年第1期213-228,共16页
This study is an extension of the previous work done with ARS-680 Environmental Chamber. Drying is a complex operation that demands much energy and time. Drying is essentially important for preservation of ginger rhiz... This study is an extension of the previous work done with ARS-680 Environmental Chamber. Drying is a complex operation that demands much energy and time. Drying is essentially important for preservation of ginger rhizome. Drying of ginger was modeled, and then the effective diffusion coefficient and activation energy were determined. For this purpose, the experiments were done at six levels of varied temperatures: 10°C, 20°C, 30°C, 40°C, 50°C and 60°C. The values of effective diffusion coefficients obtained in this work for the variously treated ginger rhizomes closely agreed with the average effective diffusion coefficients of other notable authors who determined the drying kinetics and convective heat transfer coefficients of ginger slices. 展开更多
关键词 Activation Energy Diffusion Coefficients Ginger Rhizomes drying Model drying Time Moisture Ratio Thin Layer
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Modeling the Drying Kinetics of Pigeon Pea [Cajanus cajan (L.) Millspaugh]
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作者 Nadia Pamela Gladys Pambou-Tobi Arnaud Wenceslas Geoffroy Tamba Sompila +3 位作者 Michel Elenga Reyes Herdenn Gampoula Gloire Horiane Louya Banzouzi Sylvia Petronille Ntsossani 《Open Journal of Applied Sciences》 2024年第6期1425-1436,共12页
We set out to model the oven-drying kinetics of a legume known as pigeon pea, harvested in the Bouenza department in the south-west of the Republic of Congo. The drying kinetics of pigeon peas was carried out in an ov... We set out to model the oven-drying kinetics of a legume known as pigeon pea, harvested in the Bouenza department in the south-west of the Republic of Congo. The drying kinetics of pigeon peas was carried out in an oven under experimental conditions using temperatures of: 50°C, 60°C and 70°C. Seven mathematical models were used to describe pigeon pea drying. During drying, water loss was faster and shorter at 70°C [10.446 g/25 g wet weight (wwb) for 320 min (5.3 h)] compared to 50°C [10.996 g/25 g wet weight (wwb) for 520 min (8.6 h)] and 60°C [10.616 g/25 g wet weight (wwb) for 420 min (7.0 h)] where it was slower and longer. With regard to modeling, and based on the principle of choosing the right model focusing on the high value of R2 and low values of χ2 and RMSE, two models were selected, the Midili model for temperatures of 50°C and 60°C and the Henderson and Pabis model modified for temperature of 70°C showed better results. The R2, χ2 and RMSE values calculated for pigeon pea are 0.99985, 3.93404E-5 and 0.00627;0.9997, 9.245E-5 and 0.00962;0.99996, 1.56332E-5 and 0.00395 respectively at 50°C, 60°C and 70°C. 展开更多
关键词 Cajanus cajan LEGUME Kinetic Models drying
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Soil Cover in the Eastern Part of the Dried Bed of the Aral Sea
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作者 Galina Stulina Kamaladin Idirisov 《Journal of Geoscience and Environment Protection》 2024年第6期30-37,共8页
The greatest environmental disaster in Central Asiathe drying up of the Aral Seahas led to the formation of a new terrain, extending over 2.7 million hectares in Uzbekistan. This newly formed terrain is dynamically de... The greatest environmental disaster in Central Asiathe drying up of the Aral Seahas led to the formation of a new terrain, extending over 2.7 million hectares in Uzbekistan. This newly formed terrain is dynamically developing, with emerging soil formations replacing bottom sediments. This paper analyzes the results of a study on soil formation in the eastern part of the dried-up seabed, focusing on the influence of natural processes occurring there. 展开更多
关键词 Aral Sea ENVIRONMENTAL Dried Seabed Soil Cover
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Physiological and biochemical appraisal for mulching and partial rhizosphere drying of cotton 被引量:2
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作者 Rashid IQBAL Muhammad A S RAZA +5 位作者 Muhammad F SALEEM Imran H KHAN Salman AHMAD Muhammad S ZAHEER Muhammad U ASLAM Imran HAIDER 《Journal of Arid Land》 SCIE CSCD 2019年第5期785-794,共10页
Water is the main factor for the healthy life of plant.One of the main negative effects of climate change is the increasing scarcity of water that is lethal for plant.Globally,for water deficit regions(arid and semi-a... Water is the main factor for the healthy life of plant.One of the main negative effects of climate change is the increasing scarcity of water that is lethal for plant.Globally,for water deficit regions(arid and semi-arid),drought is the main factor responsible for low production of agriculture,especially for cotton.Great efforts have been and are being made to find alternatives to water saving practices.This study aimed to examine the effects of partial rhizosphere drying(PRD,half of the root system irrigated at one event,and the other half irrigated in the next event,and so on)with and/or without various mulching treatments on physiological and biochemical traits of cotton.To explore this objective,we laid out experiments in completely randomized design with factorial arrangement in the Islamia University of Bahawalpur,Pakistan in 2016.Two factors included were four mulching treatments(M0,no mulching;M1,black plastic mulching;M2,wheat straw mulching;and M3,cotton sticks mulching)and two irrigation levels(I0,control(full irrigation);and I1,PRD).Fisher's analysis of variance among means of treatments was compared using least significant difference test at 5% probability level.Results revealed that the maximum plant height,leaf area,leaf gas exchange(photosynthetic rate and stomata conductance),chlorophyll,proline and total sugar contents,and enzyme activities were higher under M2 than under other three mulching treatments.As for irrigation levels,higher values of plant height,photosynthesis and water related parameters(leaf water potential,leaf osmotic potential,leaf turgor potential,etc.)were recorded.Contents of total sugar and proline and activities of antioxidant enzymes were significantly higher in PRD-treated plants than in control plants.It was concluded that combined application of PRD and mulching was more effective than the rest of the treatments used in the experiment.Similar study can be conducted in the field by applying irrigation water in alternate rows in semi-arid regions. 展开更多
关键词 antioxidant enzymes MULCHING partIAL RHIZOSPHERE drying PHOTOSYNTHETIC rate STOMATAL conductance
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Effects of Partial Rootzone Drying on the Growth of Vitis vinifera cv.Malvasia Grafted on Different Rootstocks 被引量:2
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作者 QI Wei GUAN Xue-qiang +3 位作者 LI En-mao ZHAI Heng WANG Xiao-fang DU Yuan-peng 《Agricultural Sciences in China》 CAS CSCD 2007年第5期567-572,共6页
To lay a biological foundation for rootstocks and alternate irrigation (AI) popularization, the effects of partial rootzone drying (PRD) on the growth of the grapevine Malvasia grafted on different rootstocks were... To lay a biological foundation for rootstocks and alternate irrigation (AI) popularization, the effects of partial rootzone drying (PRD) on the growth of the grapevine Malvasia grafted on different rootstocks were investigated. Biological effects of 1/2 divided root irrigation on three combinations, i.e., Malvasia/420A, Malvasia/3309C, and Malvasia/110R, were studied by wood-boxed plants. All the plants were separated into three groups for different irrigation strategies. Mass growth of new root in alternate-irrigated plants was remarkably promoted by about 7.8-22.2% higher than the well- watered ones. However, new shoot growth, especially the internode was reduced by alternate irrigation. The average root-shoot ratio of all the three combinations was increased from 1.1 to 1.46. New root growth and internode length were decreased by fixed partial rootzone irrigation (FI) at different amount, M/3309C at 37.9 and 36.9%, M/110R at 18.4 and 22.5%, respectively. Total biomass of all the three combinations under FI decreased at the rate of 19.2-34.3% compared with well-watered ones. Water stress adaptation of grapevine mainly depends on rootstock. 110R is more efficient than 3309C and 420A in water stress adaptation. PRD-AI benefited root growth, thus improved the drought-resistant ability of grapevine. 展开更多
关键词 grapevine (Vitis vinifera) ROOTSTOCK partial rootzone drying GROWTH
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Gas-Solid Flow Behavior in a Pneumatic Conveying System for Drying Applications: Coarse Particles Feeding with a Venturi Device 被引量:1
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作者 Thiago Faggion de Pádua Rodrigo Béttega José Teixeira Freire 《Advances in Chemical Engineering and Science》 2015年第3期225-238,共14页
The feeding of coarse particles (>0.5 mm diameter) directly into a riser operating at positive pressure is important for drying and pre-heating applications. The presence of the feeding device can lead to heterogen... The feeding of coarse particles (>0.5 mm diameter) directly into a riser operating at positive pressure is important for drying and pre-heating applications. The presence of the feeding device can lead to heterogeneity of drying and heating, and is the main factor responsible for pressure loss in short conveying systems. However, there is a lack of information concerning the axial and radial distributions of coarse particles in this type of configuration, despite the recent advances when dealing with fine particles (FCC catalyst). The present work therefore investigates a vertical venturi feeder with the conveying system operating in dilute-phase regime with 1 mm spherical glass particles. Experimental assays revealed the behavior of the mass flow rate of solids in the system, and pressure measurements were made along the riser in order to evaluate the accuracy of simulations. Euler-Euler simulations provided close estimation of the experimental pressure drop and the pressure drop according to distance in the linear region. Simulation of the fluid dynamics in the riser showed that solids clusters were formed at low concentrations near the feeding device, reflecting heterogeneity in the solid phase volume fraction. 展开更多
关键词 Pneumatic CONVEYING VENTURI FEEDER Coarse particles drying CFD
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Investigation on microstructure evolution of clayey soils: A review focusing on wetting/drying process 被引量:3
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作者 Chao-Sheng Tang Qing Cheng +2 位作者 Xuepeng Gong Bin Shi Hilary I.Inyang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第1期269-284,共16页
Variability in moisture content is a common condition in natural soils.It influences soil properties significantly.A comprehensive understanding of the evolution of soil microstructure in wetting/drying process is of ... Variability in moisture content is a common condition in natural soils.It influences soil properties significantly.A comprehensive understanding of the evolution of soil microstructure in wetting/drying process is of great significance for interpretation of soil macro hydro-mechanical behavior.In this review paper,methods that are commonly used to study soil microstructure are summarized.Among them are scanning electron microscope(SEM),environmental SEM(ESEM),mercury intrusion porosimetry(MIP)and computed tomography(CT)technology.Moreover,progress in research on the soil microstructure evolution during drying,wetting and wetting/drying cycles is summarized based on reviews of a large body of research papers published in the past several decades.Soils compacted on the wet side of op-timum water content generally have a matrix-type structure with a monomodal pore size distribution(PSD),whereas soils compacted on the dry side of optimum water content display an aggregate structure that exhibits bimodal PSD.During drying,decrease in soil volume is mainly caused by the shrinkage of inter-aggregate pores.During wetting,both the intra-and inter-aggregate pores increase gradually in number and sizes.Changes in the characteristics of the soil pore structure significantly depend on stress state as the soil is subjected to wetting.During wetting/drying cycles,soil structural change is not completely reversible,and the generated cumulative swelling/shrinkage deformation mainly derives from macro-pores.Furthermore,based on this analysis and identified research needs,some important areas of research focus are proposed for future work.These areas include innovative methods of sample preparation,new observation techniques,fast quantitative analysis of soil structure,integration of microstructural parameters into macro-mechanical models,and soil microstructure evolution charac-teristics under multi-field coupled conditions. 展开更多
关键词 Soil microstructure Pore size distribution(PSD) Wetting/drying cycle SUCTION Volume change
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Hydraulic and volume change behaviors of compacted highly expansive soil under cyclic wetting and drying 被引量:3
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作者 Mohamed Farid Abbas Abdullah Ali Shaker Mosleh A.Al-Shamrani 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第2期486-499,共14页
The wide engineered application of compacted expansive soils necessitates understanding their behavior under field conditions.The results of this study demonstrate how seasonal climatic variation and stress and bounda... The wide engineered application of compacted expansive soils necessitates understanding their behavior under field conditions.The results of this study demonstrate how seasonal climatic variation and stress and boundary conditions individually or collectively influence the hydraulic and volume change behavior of compacted highly expansive soils.The cyclic wetting and drying(CWD)process was applied for two boundary conditions,i.e.constant stress(CS)and constant volume(CV),and for a wide range of axial stress states.The adopted CWD process affected the hydraulic and volume change behaviors of expansive soils,with the first cycle of wetting and drying being the most effective.The CWD process under CS conditions resulted in shrinkage accumulation and reduction in saturated hydraulic conductivity(k sat).On the other hand,CWD under CV conditions caused a reduction of swell pressure while has almost no impact on k sat.An elastic response to CWD was achieved after the third cycle for saturated hydraulic conductivity(k sat),the third to fourth cycle for the volume change potential under the CV conditions,and the fourth to fifth cycle for the volume change potential under the CS conditions.Finally,both swell pressure(s s)and saturated hydraulic conductivity(k sat)are not fundamental parameters of the expansive soil but rather depend on stress,boundary and wetting conditions. 展开更多
关键词 Expansive soils Hydraulic conductivity Volume change potential Cyclic wetting and drying(CWD) Swell pressure
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Modeling and simulation of solvent behavior and temperature distribution within long stick propellants with large web thickness undergoing drying 被引量:2
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作者 Enfa Fu Qianling Liu +3 位作者 Yu Luan Yao Zhu Weidong He Zhenggang Xiao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第10期42-55,共14页
Drying is a complicated physical process which involves simultaneous heat and mass transfer in the removal of solvents inside propellants.Inappropriate drying techniques may result in the formation of a hard skin laye... Drying is a complicated physical process which involves simultaneous heat and mass transfer in the removal of solvents inside propellants.Inappropriate drying techniques may result in the formation of a hard skin layer near the surface to block the free access of most solvent through for long stick propellants with large web thickness,which lead to lower drying efficiency and worse drying quality.This study aims to gain a comprehensive understanding of drying process and clarify the mechanism of the blocked layer near the propellant surface.A new three-dimensional coupled heat and mass transfer(3D-CHMT)model was successfully developed under transient conditions.The drying experiment results show that the 3DCHMT model could be applied to describe the drying process well since the relative error of the content of solvent between simulation and experiment values is only 5.5%.The solvent behavior simulation demonstrates that the mass transfer process can be divided into super-fast(SF)and subsequent minorfast(MF)stages,and the SF stage is vital to the prevention of the blocked layer against the free access for solvent molecules inside propellant grains.The effective solvent diffusion coefficient(Deff)of the propellant surface initially increases from 3.4×10^(-6)to 5.3×10^(-6)m^(2)/s as the temperature increases,and then decreases to 4.1×10^(-8)m^(2)/s at 60-100 min.The value of Deffof surface between 0-1.4 mm has a unique trend of change compared with other regions,and it is much lower than that of the internal at100 min under simulation conditions.Meanwhile,the temperature of the propellant surface increases rapidly at the SF stage(0-100 min)and then very slowly thereafter.Both the evolution of Deffand temperature distribution demonstrate that the blocked layer near the propellant surface has been formed in the time period of approximately 0-100 min and its thickness is about 1.4 mm.To mitigate the formation of blocked layer and improve its drying quality of finial propellant products effectively,it should be initially dried at lower drying temperature(30-40℃)in 0-100 min and then dried at higher drying temperature(50-60℃)to reduce drying time for later drying process in double base gun propellants.The present results can provide theoretical guidance for drying process and optimization of drying parameters for long stick propellants with large web thickness. 展开更多
关键词 Stick propellants drying Large web thickness 3D numerical modeling Heat transfer Solvent behavior
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Diversity of Arbuscular Mycorrhizal Fungi Associated with Six Rice Cultivars in Italian Agricultural Ecosystem Managed with Alternate Wetting and Drying 被引量:1
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作者 Veronica VOLPE Franco MAGURNO +2 位作者 Paola BONFANTE Stefano GHIGNONE Erica LUMINI 《Rice science》 SCIE CSCD 2023年第4期348-358,I0028-I0030,共14页
Alternate wetting and drying(AWD)system,in which water has been reduced by approximately 35%with an increased occurrence of beneficial arbuscular mycorrhizal(AM)symbiosis and no negative impact on rice yield,was propo... Alternate wetting and drying(AWD)system,in which water has been reduced by approximately 35%with an increased occurrence of beneficial arbuscular mycorrhizal(AM)symbiosis and no negative impact on rice yield,was proposed to utilize water and nutrients more sustainable.In this study,we selected six rice cultivars(Centauro,Loto,Selenio,Vialone nano,JSendra and Puntal)grown under AWD conditions,and investigated their responsiveness to AM colonization and how they select diverse AM taxa.In order to investigate root-associated AM fungus communities,molecular cloning-Sanger sequencing on small subunit rDNA data were obtained from five out of the six rice cultivars and compared with Next Generation Sequencing(NGS)data,which were previously obtained in Vialone nano.The results showed that all the cultivars were responsive to AM colonization with the development of AM symbiotic structures,even if with differences in the colonization and arbuscule abundance in the root systems.We identified 16 virtual taxa(VT)in the soil compartment and 7 VT in the root apparatus.We emphasized that the NGS analysis gives additional value to the results thanks to a more in-depth reading of the less represented AM fungus taxa. 展开更多
关键词 alternate wetting and drying system arbuscular mycorrhizal fungi rice molecular diversity virtual taxa
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Development of Polycaprolactone/Poly(Vinyl Alcohol)/Clay Microparticles by Spray Drying 被引量:1
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作者 Mariana Sato de S. de B. Monteiro Claudia Lopes Rodrigues +1 位作者 Eduardo Miguez Maria Inês B. Tavares 《Materials Sciences and Applications》 2016年第10期575-592,共18页
In this study, nanostructured microparticles was developed with polycaprolactone (PCL), poly(vinyl alcohol) (PVAL) and nanoparticles of the commercial sodium clay NT-25&reg;by using the spray drying technique. The... In this study, nanostructured microparticles was developed with polycaprolactone (PCL), poly(vinyl alcohol) (PVAL) and nanoparticles of the commercial sodium clay NT-25&reg;by using the spray drying technique. The systems obtained were characterized by Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Dynamic Laser Light Scattering (DLS) and Differential Scanning Calorimetry (DSC). The NMR <sup>13</sup>C and FTIR techniques showed that both polymers were present in the microparticles and the DSC analysis revealed a small variation in the glass transition temperature of the PCL. The XRD and SEM analyses showed that the microparticles produced were amorphous and had a concave morphology. The NT-25 nanoload reduced the microparticles’ size due to the multiple interactions formed in the hybrid nanocomposite material. Therefore, it was possible to develop microparticles by using biodegradable and biocompatible polymers, with different polarities, allowing the incorporation of hydrophilic and hydrophobic materials and enabling the inclusion of otherwise incompatible materials in the same system. 展开更多
关键词 MICROpartICLES Spray drying POLYCAPROLACTONE Poly(Vinyl Alcohol) Sodium Clay NT-25
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Drying kinetics of soy protein isolate-corn starch film during preparation and its moisture adsorption characteristics during storage 被引量:1
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作者 Tingwei Zhu Jinyu Yang +3 位作者 Wanting Qin Yadong Tian Yingying Wang Xingfeng Guo 《Grain & Oil Science and Technology》 CAS 2023年第3期120-126,共7页
To better understand the mass transfer process of moisture in the soy protein isolate-corn starch(SPI-CS)films during preparation and storage process,the drying kinetics model of SPI-CS films with different formation ... To better understand the mass transfer process of moisture in the soy protein isolate-corn starch(SPI-CS)films during preparation and storage process,the drying kinetics model of SPI-CS films with different formation conditions during the drying process and the moisture adsorption characteristics of the SPI-CS films under different humidity conditions were investigated.Within the range of experimental conditions,the moisture migration rule in the SPI-CS films during the drying preparation was combined with the Page model which was expressed as MR=exp(-kt^(n)).It was found that the adsorption equilibrium needed shorter time(about 3 h)when the SPI-CS films existed in the environment with lower humidity(RH<54%).Additionally,the secondorder adsorption kinetic equation was successful to describe the moisture adsorption characteristic of the SPICS films during storage under different humidity conditions. 展开更多
关键词 Soy protein isolate Corn starch FILM drying kinetics MOISTURE
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A Comparative Analysis for a Novel Irrigation Method: Partial Rootzone Drying
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作者 Alaa Abdallah El-Sadek Mona Ezo Radwan Ahmed Ali Salih 《Journal of Agricultural Chemistry and Environment》 2018年第1期34-44,共11页
Partial Rootzone Drying (PRD) is an irrigation technique which offers a means of modifying the growth and development of crops through relatively simple changes to the method of water delivery. The technique causes th... Partial Rootzone Drying (PRD) is an irrigation technique which offers a means of modifying the growth and development of crops through relatively simple changes to the method of water delivery. The technique causes the stimulation of physiological responses which are normally associated with water stress and this results in a significant reduction in water use through the production of chemical signals in drying roots. Partial drying of one half of the roots of plants grown with two root systems is rapidly translated into a reduction in transpiration and assimilation of all the crop leaves. The aim of this research is to examine and simulate the novel irrigation method (PRD), which would stimulate the endogenous stress response mechanisms of Conocarpus erectus trees in the pilot area of the Arabian Gulf University in Bahrain and wheat and maize crops in the Mashtul Pilot Area (MPA), Egypt using Saltmed model so that vigor is reduced and the efficiency of water use is enhanced. This is to be achieved by the manipulation of the hydration status of parts of a crop’s roots that could be used to control vegetative vigor without detrimental effects on canopy water relations. The PRD technique is researched for wheat as a winter crop and maize as a summer crop in Egypt. The technique causes the stimulation of physiological responses which are normally associated with water stress and this results in a significant reduction in water use through the production of chemical signals in drying roots. The results confirmed an increase in irrigation water use efficiency using PRD comparing with conventional flood irrigation. The research highly recommends applying the PRD method in the Gulf Cooperation Council (GCC) countries and in new reclaimed areas in Egypt to save water and improve crop quality. 展开更多
关键词 partIAL ROOTZONE drying Conocarpus Erectus Trees MPA GCC
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Numerical Modelling of Drying Induced Cracks in Wood Discs Using the Extended Finite Element Method
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作者 Zongying Fu Yongdong Zhou +1 位作者 Tingguo Yan Yun Lu 《Journal of Renewable Materials》 SCIE EI 2023年第1期93-102,共10页
Drying crack is a common phenomenon occurring during moisture discharge from wood,reducing efficient wood utilization.Drying crack is primarily caused by drying stress,and the reasonable methods for determining drying... Drying crack is a common phenomenon occurring during moisture discharge from wood,reducing efficient wood utilization.Drying crack is primarily caused by drying stress,and the reasonable methods for determining drying stress are sparse.In this study,the initiation and propagation of cracks during wood discs drying were simulated using the extended finite element method(XFEM).The distribution of drying stress and displacement was analyzed at different crack conditions based on the simulation results.This study aimed to solve the problem of the limitation of drying stress testing methods and provide a new idea for the study of wood drying stress.The numerical simulation results are found in good agreement with the experimental results,thus corroborating the feasibility of XFEM in modeling drying crack of wood discs.The stress concentration was observed at the crack tip region,while a minor stress was presented in the region of crack passing through,indicating that the crack formation process was also a process of releasing drying stress.Further,more energy was required to form double cracks in comparison with the single crack mode. 展开更多
关键词 Wood drying queensland peppermint drying cracks numerical simulation experimental validation XFEM
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