This study explores the thin-layer convective solar drying of Marrubium vulgare L.leaves under conditions typical of sun-rich semi-arid climates.Drying experiments were conducted at three inlet-air temperatures(40℃,5...This study explores the thin-layer convective solar drying of Marrubium vulgare L.leaves under conditions typical of sun-rich semi-arid climates.Drying experiments were conducted at three inlet-air temperatures(40℃,50℃,60℃)and two air velocities(1.5 and 2.5 m·s^(-1))using an indirect solar dryer with auxiliary temperature control.Moisture-ratio data were fitted with eight widely used thin-layer models and evaluated using correlation coefficient(r),root-mean-square error(RMSE),and Akaike information criterion(AIC).A complementary heattransfer analysis based on Reynolds and Prandtl numbers with appropriate Nusselt correlations was used to relate flow regime to drying performance,and an energy balance quantified the relative contributions of solar and auxiliary heat.The logarithmic model consistently achieved the lowest RMSE/AIC with r>0.99 across all conditions.Higher temperature and air velocity significantly reduced drying time during the decreasing-rate period,with no constantrate stage observed.On average,solar input supplied the large majority of the thermal demand,while the auxiliary heater compensated short irradiance drops to maintain setpoints.These findings provide a reproducible dataset and a modelling benchmark for M.vulgare leaves,and they support energy-aware design of hybrid solar dryers formedicinal plants in sun-rich regions.展开更多
Alternate wetting and drying irrigation(AWD)significantly influences the cooking and eating quality of rice(Oryza sativa L.).However,the mechanisms by which AWD affects rice cooking and eating quality remain unclear.L...Alternate wetting and drying irrigation(AWD)significantly influences the cooking and eating quality of rice(Oryza sativa L.).However,the mechanisms by which AWD affects rice cooking and eating quality remain unclear.Lipid and free fatty acid contents in grains correlate positively with cooking and eating quality of rice.This study examined Yangdao 6(YD6,a conventional taste indica inbred)and Nanjing 9108(NJ9108,a superior taste japonica inbred)cultivated under conventional irrigation(CI),alternate wetting and moderate drying irrigation(AWMD),and alternate wetting and severe drying irrigation(AWSD)from 10 days after transplanting to maturity.The research investigated the relationship between lipid and free fatty acid biosynthesis in grains and the cooking and eating quality of rice.Compared to CI treatment,AWMD significantly enhanced the contents of lipid,total free fatty acids(TFFAs),free unsaturated fatty acids(FUFAs),linoleic acid,and oleic acid in milled rice by increasing activities of enzymes associated with lipid synthesis,while AWSD produced opposite effects.Correlation analysis revealed that elevated levels of lipid,TFFAs,FUFAs,linoleic acid,and oleic acid contribute to improved rice cooking and eating quality.The findings demonstrate that AWMD enhances cooking and eating quality of milled rice through optimization of lipid and fatty acid synthesis in rice grains.展开更多
Soil microorganisms and labile soil organic carbon(SOC)fractions are essential factors affecting greenhouse gas(GHG)emissions in paddy fields.However,the effects of labile SOC fractions and microorganisms on GHG emiss...Soil microorganisms and labile soil organic carbon(SOC)fractions are essential factors affecting greenhouse gas(GHG)emissions in paddy fields.However,the effects of labile SOC fractions and microorganisms on GHG emissions from flooding to drying after organic fertilizer replacing for chemical fertilizer remain unclear.Here,a long-term experiment was conducted with four treatments:chemical fertilization only(control),organic fertilizer substituting 25%of chemical N fertilizer(NM1),50%of chemical N fertilizer(NM2),and NM2combined with crop straw(NMS).GHG emissions were monitored,and soil samples were collected to determine labile SOC fractions and microorganisms.Results revealed the GHG emissions in the NM2 significantly increased by 196.88%from flooding to drying,mainly due to the higher CO_(2) emissions.The GHG emissions per kg of C input in NMS was the lowest with the value of 9.17.From flooding to drying,organic fertilizer application significantly increased the readily oxidizable organic carbon(ROC)contents and C lability;the NM2 and NMS dramatically increased the SOC and non-readily oxidizable organic carbon(NROC).The bacterial communities showed significant differences among different treatments in the flooding,while the significant difference was only found between the NMS and other treatments in the drying.From flooding to drying,changing soil moisture conditions causes C fractions and microbial communities to jointly affect carbon emissions,and the NMS promoted carbon sequestration and mitigated GHG emissions.Our findings highlight the importance of the labile SOC fractions and microorganisms linked to GHG emissions in paddy fields.展开更多
This study evaluated corn kernel drying performance and quality changes using hot air drying(HAD)and infrared drying(ID)across temperatures ranging from 55℃ to 80℃.Optimal drying parameters were determined by using ...This study evaluated corn kernel drying performance and quality changes using hot air drying(HAD)and infrared drying(ID)across temperatures ranging from 55℃ to 80℃.Optimal drying parameters were determined by using the entropy weight method,with drying time,specific energy consumption,damage rate,fatty acids,starch,polyphenols,and flavonoids as indicators.Results demonstrated that ID significantly outperformed HAD,achieving drying times up to 20%shorter and reducing specific energy consumption and kernel damage by up to 79.3%and 66.7%,respectively,while also better preserving quality attributes.Both methods exhibited drying profiles characterized by acceleration,constant,and falling rate periods,although the constant rate phase was distinctly observable only at lower temperatures.The effective moisture diffusivity under ID was consistently higher than that under HAD,with a maximum increase of 20.4%.The optimal drying conditions were HAD at 65℃ and ID at 80℃.A BP model was also developed and it showed better predictive performance and adaptability than classical mathematical models.展开更多
Bananas are highly perishable after harvest,and processing them into dried products is a crucial approach to reducing losses and adding their economic values.To address the inefficiency and prolonged duration of tradi...Bananas are highly perishable after harvest,and processing them into dried products is a crucial approach to reducing losses and adding their economic values.To address the inefficiency and prolonged duration of traditional hot air drying(HAD)and the quality inconsistency associated with single infrared drying(IRD),this study proposed a novel hot air-infrared combined drying(HAD-IRD)strategy.The effects of HAD,IRD,and HAD-IRD on the drying kinetics,color,rehydration capacity,moisture diffusion mechanism,and sensory quality of banana slices were systematically investigated.The parameters of the combined drying process were optimized using an L_(9)(3^(3))orthogonal experimental design.Results indicated that both IRD and HAD-IRD significantly reduced drying time compared to single HAD.While single IRD achieved a rapid drying rate,the lack of effective convective airflow led to potential case-hardening and unstable product quality.In contrast,the HAD-IRD strategy demonstrated a synergistic effect.The optimal parameters were determined as follows:hot air temperature of 70℃,infrared temperature of 60℃,and radiation distance of 16 cm.Under these optimized conditions,HAD-IRD reduced the total drying time by over 70%while simultaneously yielding products with superior color,higher sensory scores,and improved rehydration ratio.This study confirms that HAD-IRD is an efficient and high-quality drying method for banana slices,providing a reliable theoretical foundation and technical solution for the drying of thermosensitive fruits.展开更多
The design and development of solar dryers are crucial in regions with abundant solar energy,such as Bhopal,India,where seasonal variations significantly impact the efficiency of drying processes.The paper is focused ...The design and development of solar dryers are crucial in regions with abundant solar energy,such as Bhopal,India,where seasonal variations significantly impact the efficiency of drying processes.The paper is focused on employing a comprehensive mathematical model to predict the dryer’s performance in drying the materials such as banana slices.To enhance this model,Hyper Tuned Swarm Optimization with Gradient Tree(HT_SOGT)was utilized to accurately predict and determine the optimal size of the dryer dimensions considering various mathematical calculations for material drying.The predictive model considered the influence of seasonal fluctuations,ensuring an efficient drying process with an objective function to optimize the drying time of an average of 7 hrs throughout the year.Across all recorded ambient temperatures(ranging from 16.985○C to 31.4○C),the outlet temperature of the solar dryer is consistently higher,ranging from 39.085○C to 66.2○C.The results show that the optimized dryer design,based on HT_SOGT modelling,significantly improves drying efficiency of the materials across varying conditions,making it suitable for sustainable applications in agriculture and food processing industries in the Bhopal region.展开更多
The dynamics of the drying process of polymer solutions are important for the development of coatings and films.In the present work,digital holographic microscopy(DHM)was performed to capture the drying dynamics of po...The dynamics of the drying process of polymer solutions are important for the development of coatings and films.In the present work,digital holographic microscopy(DHM)was performed to capture the drying dynamics of poly(ethylene oxide)(PEO)droplets using a gold nanoparticle tracer,where the heterogeneous flow field in different regions was illustrated.This demonstrates that the gold nanoparticles at either the center or the edge regions of the droplet exhibit anisotropic kinematic behavior.At early stage,Marangoni backflow causes gold nanoparticles to move towards the edge firstly,and the circles back towards the droplet center after arriving the contact line with a sudden increase in z axis for 10.4μm,indicating the scale of the upward-moving microscopic flow vortices.This phenomenon does not occur in water droplets in the absence of polymers.The gold nanoparticles underwent Brownian-like motion at the center of the PEO droplet or water droplet owing to the low perturbation of the flow field.At the late stage of pinning of the PEO droplets,the motion showed multiple reverses in the direction of the gold nanoparticles,indicating the complexity of the flow field.This study enhances the understanding of the drying dynamics of polymer solution droplets and offers valuable insights into the fabrication of surface materials.展开更多
To study the effects of fine-aggregates on the drying-shrinkage properties of concrete,two types of manufactured-sand and one type of natural sand(excluding<75μm particles)were selected for tests,and nine sets of ...To study the effects of fine-aggregates on the drying-shrinkage properties of concrete,two types of manufactured-sand and one type of natural sand(excluding<75μm particles)were selected for tests,and nine sets of concrete drying shrinkage tests were designed with three strength grade(C30,C40,and C50)as variables.By observing the drying-shrinkage deformation of the specimens over 360 days,the effects of fine-aggregate properties on the drying shrinkage properties of concrete of different strength grades were analyzed and a prediction model was developed.Compared with natural sand concrete,the development of drying shrinkage of manufactured-sand concrete exhibits the phenomenon of advancement.The apparent density of the fine-aggregate and the strength grade are the two main factors affecting the limit value of the drying shrinkage of concrete.With a reduction in the water absorption or apparent density of the fine-aggregate or the strength grade of concrete prepared using the same fine-aggregate,the prediction accuracy of the existing models decreases.According to the GL 2000 model,two coefficients-and-were introduced to propose a prediction model for the drying shrinkage of fine-aggregate concrete,which is applicable to different strength grades.展开更多
The low-temperature spray drying technology was developed to process instant berry powder with high efficiency and higher anthocyanin retention.The maltodextrin,whey protein and inulin were selected as additives for i...The low-temperature spray drying technology was developed to process instant berry powder with high efficiency and higher anthocyanin retention.The maltodextrin,whey protein and inulin were selected as additives for instant properties formation in berry powder.The effects of inlet air temperature(40℃–80℃),vacuum degree(0.02–0.06 MPa)and additive amount on the physicochemical properties of berry powder were analyzed through solubility,anthocyanin retention and powder yield,based on moisture content and microstructure.The findings indicated that adding maltodextrin to berry enhanced the powder yield and instant solubility.Whey protein,as an additive,provided effective protection for the anthocyanins of berry powder,and the addition less than 10 g·100^(-1) g improved the powder yield.Inulin,as an additive,reduced moisture content of berry powder,which was conducive to the higher anthocyanin retention and solubility.Technique for order preference by similarity to ideal solution(TOPSIS)analysis was conducted to optimize the spray drying parameters for anthocyanin protection and solubility.The addition of 100%maltodextrin enhanced anthocyanin protection and solubility,while maintaining the desired moisture content and powder yield.This approach was used to evaluate the comprehensive quality of berry powder.This research can provide technical guidance for producing berry powder under low-temperature spray drying.展开更多
Purpose–Severe scarcity of natural river sand(RS),exacerbated by environmental protection policies and extraction constraints,has significantly impacted aggregate supply for railway concrete.While manufactured sand(M...Purpose–Severe scarcity of natural river sand(RS),exacerbated by environmental protection policies and extraction constraints,has significantly impacted aggregate supply for railway concrete.While manufactured sand(MS)offers a substitute for RS in railway applications,its widespread adoption in high-strength railway prestressed structures is challenged by lack of drying shrinkage and creep research data on concrete.Design/methodology/approach–High-strength manufactured sand concrete(MSC)was prepared using MS with varying lithologies and stone powder contents.Its drying shrinkage and creep behaviors were evaluated in accordance with the Chinese standard GB/T 50082.The deformation mechanism was analyzed by combining nano-scratch testing.Findings–Compared to RS concrete,MSC from all tested lithologies showed higher drying shrinkage but lower creep deformation.The drying shrinkage rose steadily with increased stone powder content,while the creep strain displayed a distinct non-linear trend,decreasing first before rising.To prepare low-deformation MSC,select high-strength MS and limit stone powder content not greater 10%.Nano-scratch tests indicated that harder MS particles suppress microcracking at the interfacial transition zone(ITZ),improving the creep resistance.The predictive models for drying shrinkage and creep were also developed by incorporating coefficients for stone powder and lithology effects.Originality/value–These findings serve as a foundation for the application of MSC in railway prestressed structures,offering both theoretical and practical guidance.展开更多
This work investigates a combined cooling,heating,and power(CCHP)generation system utilizing waste energy.A cascade-CCHP system is developed,consisting of a 23.65-kWe organic Rankine cycle(ORC),a 4.00-kW adsorption ch...This work investigates a combined cooling,heating,and power(CCHP)generation system utilizing waste energy.A cascade-CCHP system is developed,consisting of a 23.65-kWe organic Rankine cycle(ORC),a 4.00-kW adsorption chiller,a 4.11-kW absorption chiller,a 15.99-kW drying room,and an incinerator of 150 kg/h.A net energy production of 36.08 kWh is achieved from a CCHP energy efficiency of 9.98%.The levelized cost for producing a total energy output of 2,020,592 kWh over a lifespan of 20 years is approximately 0.106 USD/kWh.The life cycle assessment(LCA)yields a single score of approximately 0.000151 Pt,mainly attributed to raw materials used in the construction process of 87.16%.In addition,the combustion ash is processed into concrete blocks measuring 39 cm×19 cm×7 cm,in accordance with the Industrial Product Standard(TIS)58-2533,with a water absorption value below 5%and a compressive strength exceeding 25 kg/cm2.The CCHP system demonstrates a novel method of waste-to-energy(WtE),and the construction material from waste combustion ash can also support a new concept of waste-to-zero(WtZ).展开更多
Onsite sanitation offers a sustainable alternative to centralized wastewater treatment;however,effective faecal sludge management is crucial for safe disposal and resource recovery.Among emerging treatment solutions,s...Onsite sanitation offers a sustainable alternative to centralized wastewater treatment;however,effective faecal sludge management is crucial for safe disposal and resource recovery.Among emerging treatment solutions,solar thermal drying holds significant promise to reduce sludge moisture content and enhance handling.Despite this potential,its application remains limited,with important knowledge gaps,particularly concerning the drying kinetics under different environmental and operational conditions.This study aims to fill these gaps by investigating the solar thermal drying behaviour of faecal sludge from ventilated improved pit latrines(VIPs)and urine-diverting dry toilets(UDs),with a specific focus on how air temperature and velocity influence drying performance.A bench-scale solar drying apparatus was used to investigate thin-layer sludge drying kinetics under controlled airflow conditions.The drying experiments were conducted at varying air temperatures(ambient,40℃,and 80℃)and velocities(0,0.5,and 1 m/s),where heated air was supplied via an electric resistance heater.Key drying parameters-including drying rate,critical moisture content,effective moisture diffusivity,and activation energy-were determined.Results showed that drying proceeded through a constant-rate period followed by a falling-rate period,with the critical moisture content ranging from 1.41 to 1.78 g/g db.Higher temperatures and airflow reduced the duration of the constant-rate phase,increased drying rates(0.31–0.99 g/g·min·m^(2)),and enhanced moisture diffusivity(4.56×10^(−9) to 1.52×10^(−8) m^(2)/s).Activation energy decreased with increased airflow,suggesting reduced temperature sensitivity.Thermal efficiency ranged from 14.6%to 35.1%,with solar energy contributing 73%–95% of total input.VIP sludge dried faster than UD sludge,which showed signs of surface crusting that limited moisture transfer.This research offers valuable insights into solar drying design and operation,providing scientific evidence to improve faecal sludge treatment strategies in decentralized sanitation systems.展开更多
The effect of a storage system on drying time and estimation of drying parameters of cocoa beans using an indirect solar dryer with a sensible heat energy storage system (stones which act as both absorber and heat sto...The effect of a storage system on drying time and estimation of drying parameters of cocoa beans using an indirect solar dryer with a sensible heat energy storage system (stones which act as both absorber and heat storage media) is the main subject of this article. This dryer, which uses stones as storage material and is made of wood and plywood, was used to dry a quantity of 5 kg of fermented cocoa beans. The drying parameters for the drying curves and the drying efficiency of cocoa beans were established and studied. The drying curves were modelled from semi-empirical models. The results showed that the moisture of cocoa beans decreased from 60% to 7% in wet basis. With a solar collector and drying efficiency of 40% and 34%, respectively. And this with a maximum average difference temperature between the drying air and the ambient temperature of 13.25˚C day or night. The best concordances are obtained with R2 values of 0.9983, 0.9843, 0.9813 and 0.9837 respectively from the models of Hii, Jena and Das, Demir et al. and Alibas.展开更多
As a typical sedimentary soft rock,mudstone has the characteristics of being easily softened and disintegrated under the effect of wetting and drying(WD).The first cycle of WD plays an important role in the entire WD ...As a typical sedimentary soft rock,mudstone has the characteristics of being easily softened and disintegrated under the effect of wetting and drying(WD).The first cycle of WD plays an important role in the entire WD cycles.X-ray micro-computed tomography(micro-CT)was used as a non-destructive tool to quantitatively analyze microstructural changes of the mudstone due to the first cycle of WD.The test results show that WD leads to an increase of pore volume and pore connectivity in the mudstone.The porosity and fractal dimension of each slice of mudstone not only increase in value,but also in fluctuation amplitude.The pattern of variation in the frequency distribution of the equivalent radii of connected,isolated pores and pore throats in mudstone under WD effect satisfies the Gaussian distribution.Under the effect of WD,pores and pore throats with relatively small sizes increase the most.The sphericity of the pores in mudstones is positively correlated with the pore radius.The WD effect transforms the originally angular and flat pores into round and regular pores.This paper can provide a reference for the study of the deterioration and catastrophic mechanisms of mudstone under wetting and drying cycles.展开更多
Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a la...Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a large amount of thermal energy to conquer the phase-change latent heat of moisture.Herein,we report a non-phase change technology based on particle high-speed self-rotation in a cyclone for fast,low-temperature drying of viscous sludge with high-moisture contents.Dispersed phase medium(DPM)is introduced into the cyclone self-rotation drying(CSRD)reactor to enhance the dispersion of the viscous sludge.The effects of carrier gas temperature,feeding rate,size,and proportion of DPM particles in the drying process are systematically examined.Under optimal operating conditions,the weighted content of moisture in the viscous sludge could be reduced from 80%to 15.01%in less than 5 s,achieving a high drying efficiency of 95.79%.Theoretical calculations also reveal that 89.26%of the moisture is removed through non-phase change pathway,contributing to a 522-fold increase in the drying rate of CSRD compared to TED technology.This investigation presents a sustainable effective approach for high moisture viscous sludge treatment with low energy consumption and carbon emissions.展开更多
Côte d’Ivoire has been the world’s leading producer of cocoa beans for several decades. Apart from this production performance, the quality of the beans, which are mainly exported to the major chocolate-making ...Côte d’Ivoire has been the world’s leading producer of cocoa beans for several decades. Apart from this production performance, the quality of the beans, which are mainly exported to the major chocolate-making countries, presents a quality problem to the point of suffering a discount on the international market. One of these quality problems is the content of ochratoxin A, a mycotoxin produced by fungi. Finally, to verify the level of contamination in beans produced in Côte d’Ivoire, a study was carried out. It consisted of collecting information on fermentation and drying times (The two major post-harvest operations) and collecting beans, which were analyzed by electrophoresis using the High Performance Liquid Chromatography (HPLC) method. The results obtained show ochratoxin A contents of between 0.05 µg/kg and 0.17 µg/kg. The general level of contamination is therefore very low and below the tolerable limit which is 2 µg/kg. In addition, the correlative study between the fermentation and drying times of the beans revealed no significant influence (p < 0.01) of the duration of these operations on the level of ochratoxin A contamination. Major contamination can occur after post-harvest activities carried out by producers. This is certainly due to the development of fungi responsible for the production of ochratoxin A during the period of storage and marketing of cocoa beans in conditions of high humidity in storage enclosures. Producers need to be made more aware of the need to ensure that cocoa beans are properly dried and stored in dry areas to avoid moisture build-up, which is a source of mould growth and ochratoxin A production.展开更多
The aim of this paper was to characterize through experiment the moisture and temperature kinetic behavior of Eucalyptus gomphocephala wood samples using microwave heating(MWH)in two scenarios:intermittently and conti...The aim of this paper was to characterize through experiment the moisture and temperature kinetic behavior of Eucalyptus gomphocephala wood samples using microwave heating(MWH)in two scenarios:intermittently and continuously.The mechanical properties and surface appearance of the heated samples were also investigated.Continuous and intermittent microwave drying kinetic experiments were conducted at a frequency of 2.45 GHz using a microwave laboratory oven at 300,500,and 1000 watts.Drying rate curves indicated three distinct phases of MWH.Increasing the microwave power with a shorter drying time led to rapid increases in internal temperature and water evaporation rates of the heated samples.Mechanical results indicated that samples heated under continuous MW(Microwave)power at 300 watts had a modulus of rupture(MOR)and modulus of elasticity(MOE)in three static bending tests higher than 29%and 36%,respectively,than samples heated at 1000 watts.Intermittent microwave heating(IMWH)of samples at 300 and 1000 watts produced the highest MOR and MOE values of 31%and 51%,respectively,unlike those heated under continuous microwave heating(CMWH).External qualitative observation showed that samples heated at high microwave power had severe surface checks.These defects were missing when using IMWH.An analysis of variance(ANOVA)showed that mechanical properties were linked to both microwave power level and the heating scenario,except for MOR in axial compression under CMWH.展开更多
Alternate wetting and soil drying irrigation(AWD)technique is crucial in infuencing grain quality in rice(Oryza sativa L.).Lipids are the third most abundant constituents in rice grains,after starch and proteins,and a...Alternate wetting and soil drying irrigation(AWD)technique is crucial in infuencing grain quality in rice(Oryza sativa L.).Lipids are the third most abundant constituents in rice grains,after starch and proteins,and are closely related to grain quality.However,it remains unclear about the changes in lipids profling under different AWD regimes.This study set up three irrigation regimes including conventional irrigation(CI),alternate wetting and moderate soil drying irrigation(AWMD),and alternate wetting and severe soil drying irrigation(AWSD).It explored lipidome changes in milled rice of Yangdao 6(YD6)using the untargeted lipidomics approach and analyzed rice cooking and eating quality.The results identifed seven lipid classes,55 lipid subclasses,and 1,086 lipid molecular species.Compared with the CI regime,the AWMD regime mainly altered lipid subclasses consisting of triglyceride(TG),ceramide(Cer),diglyceride(DG),bis-methyl lysophosphatidic acid(BisMePA),phosphocholine(PC),phosphoethanolamine(PE),monogalactosyldiacylglycerol(MGDG),and digalactosyl diglyceride(DGDG)in milled rice and improved cooking and eating quality of rice;in contrast,the AWSD regime distinctly changed lipid subclasses like TG,Cer,DG,PC,PE,hexosylceramide(Hex1Cer),DGDG,and BisMePA and degraded cooking and eating quality of rice.Specifcally,AWMD most signifcantly altered the expressions of lipid molecules,including DGDG(18:0_18:2),DGDG(16:0_14:0),PC(33:1),Cer(t17:0_26:0),and Cer(t17:0_16:0);AWSD most obviously influenced the expressions of TG(6:0_14:0_18:3),PC(41:1),TG(19:1_18:4_18:4),Hex1Cer(d18:2_24:0+O),and Hex1Cer(d18:2_24:1).These 10 altered lipid molecules in milled rice can be preferentially used for investigating their relationships with grain quality in rice.展开更多
文摘This study explores the thin-layer convective solar drying of Marrubium vulgare L.leaves under conditions typical of sun-rich semi-arid climates.Drying experiments were conducted at three inlet-air temperatures(40℃,50℃,60℃)and two air velocities(1.5 and 2.5 m·s^(-1))using an indirect solar dryer with auxiliary temperature control.Moisture-ratio data were fitted with eight widely used thin-layer models and evaluated using correlation coefficient(r),root-mean-square error(RMSE),and Akaike information criterion(AIC).A complementary heattransfer analysis based on Reynolds and Prandtl numbers with appropriate Nusselt correlations was used to relate flow regime to drying performance,and an energy balance quantified the relative contributions of solar and auxiliary heat.The logarithmic model consistently achieved the lowest RMSE/AIC with r>0.99 across all conditions.Higher temperature and air velocity significantly reduced drying time during the decreasing-rate period,with no constantrate stage observed.On average,solar input supplied the large majority of the thermal demand,while the auxiliary heater compensated short irradiance drops to maintain setpoints.These findings provide a reproducible dataset and a modelling benchmark for M.vulgare leaves,and they support energy-aware design of hybrid solar dryers formedicinal plants in sun-rich regions.
基金supported by the Natural Science Foundation of Jiangsu Province,China(BK20241931 and BK 20221371)the National Natural Science Foundation of China(32071943,32372214,and 31901444)the National Key Research and Development Program of China(2022YFD2300304)。
文摘Alternate wetting and drying irrigation(AWD)significantly influences the cooking and eating quality of rice(Oryza sativa L.).However,the mechanisms by which AWD affects rice cooking and eating quality remain unclear.Lipid and free fatty acid contents in grains correlate positively with cooking and eating quality of rice.This study examined Yangdao 6(YD6,a conventional taste indica inbred)and Nanjing 9108(NJ9108,a superior taste japonica inbred)cultivated under conventional irrigation(CI),alternate wetting and moderate drying irrigation(AWMD),and alternate wetting and severe drying irrigation(AWSD)from 10 days after transplanting to maturity.The research investigated the relationship between lipid and free fatty acid biosynthesis in grains and the cooking and eating quality of rice.Compared to CI treatment,AWMD significantly enhanced the contents of lipid,total free fatty acids(TFFAs),free unsaturated fatty acids(FUFAs),linoleic acid,and oleic acid in milled rice by increasing activities of enzymes associated with lipid synthesis,while AWSD produced opposite effects.Correlation analysis revealed that elevated levels of lipid,TFFAs,FUFAs,linoleic acid,and oleic acid contribute to improved rice cooking and eating quality.The findings demonstrate that AWMD enhances cooking and eating quality of milled rice through optimization of lipid and fatty acid synthesis in rice grains.
基金the support of the National Natural Science Foundation of China(No.42107247)the National Key Research and Development Project(No.2022YFD1901605)+1 种基金the Natural Science Foundation of Sichuan Province(Nos.2025YFHZ0142 and 2024NSFSC0800)the Tobacco Science Foundation of Sichuan Province(No.SCYC202407)。
文摘Soil microorganisms and labile soil organic carbon(SOC)fractions are essential factors affecting greenhouse gas(GHG)emissions in paddy fields.However,the effects of labile SOC fractions and microorganisms on GHG emissions from flooding to drying after organic fertilizer replacing for chemical fertilizer remain unclear.Here,a long-term experiment was conducted with four treatments:chemical fertilization only(control),organic fertilizer substituting 25%of chemical N fertilizer(NM1),50%of chemical N fertilizer(NM2),and NM2combined with crop straw(NMS).GHG emissions were monitored,and soil samples were collected to determine labile SOC fractions and microorganisms.Results revealed the GHG emissions in the NM2 significantly increased by 196.88%from flooding to drying,mainly due to the higher CO_(2) emissions.The GHG emissions per kg of C input in NMS was the lowest with the value of 9.17.From flooding to drying,organic fertilizer application significantly increased the readily oxidizable organic carbon(ROC)contents and C lability;the NM2 and NMS dramatically increased the SOC and non-readily oxidizable organic carbon(NROC).The bacterial communities showed significant differences among different treatments in the flooding,while the significant difference was only found between the NMS and other treatments in the drying.From flooding to drying,changing soil moisture conditions causes C fractions and microbial communities to jointly affect carbon emissions,and the NMS promoted carbon sequestration and mitigated GHG emissions.Our findings highlight the importance of the labile SOC fractions and microorganisms linked to GHG emissions in paddy fields.
基金financially supported by the Natural Science Foundation of Hunan Province(project No.2024JJ8037:https://kjt.hunan.gov.cn/kjt/xxgk/tzgg/tzgg_1/202403/t20240311_33144606.html,accessed on 27 October 2025)。
文摘This study evaluated corn kernel drying performance and quality changes using hot air drying(HAD)and infrared drying(ID)across temperatures ranging from 55℃ to 80℃.Optimal drying parameters were determined by using the entropy weight method,with drying time,specific energy consumption,damage rate,fatty acids,starch,polyphenols,and flavonoids as indicators.Results demonstrated that ID significantly outperformed HAD,achieving drying times up to 20%shorter and reducing specific energy consumption and kernel damage by up to 79.3%and 66.7%,respectively,while also better preserving quality attributes.Both methods exhibited drying profiles characterized by acceleration,constant,and falling rate periods,although the constant rate phase was distinctly observable only at lower temperatures.The effective moisture diffusivity under ID was consistently higher than that under HAD,with a maximum increase of 20.4%.The optimal drying conditions were HAD at 65℃ and ID at 80℃.A BP model was also developed and it showed better predictive performance and adaptability than classical mathematical models.
基金funded by the National Natural Science Foundation of China,grant number 52306124(received by Dan Huang),URL:https://mp.weixin.qq.com/s/HHNYjgYKAynqYR7ySxYwzQ(accessed on 01 January 2025)the Changsha Municipal Natural Science Foundation,grant number kq2402259(received by Shuai Huang),URL:http://kjj.changsha.gov.cn/zfxxgk/tzgg_27202/202501/t20250122_11726939.html(accessed on 01 January 2025)the Regional Joint Funds of the Natural Science Foundation of Hunan Province,grant num-ber 2025JJ70463(received by Shuai Huang),URL:https://kjt.hunan.gov.cn/kjt/xxgk/tzgg/tzgg_1/202502/t20250212_33585991.html(accessed on 01 January 2025).
文摘Bananas are highly perishable after harvest,and processing them into dried products is a crucial approach to reducing losses and adding their economic values.To address the inefficiency and prolonged duration of traditional hot air drying(HAD)and the quality inconsistency associated with single infrared drying(IRD),this study proposed a novel hot air-infrared combined drying(HAD-IRD)strategy.The effects of HAD,IRD,and HAD-IRD on the drying kinetics,color,rehydration capacity,moisture diffusion mechanism,and sensory quality of banana slices were systematically investigated.The parameters of the combined drying process were optimized using an L_(9)(3^(3))orthogonal experimental design.Results indicated that both IRD and HAD-IRD significantly reduced drying time compared to single HAD.While single IRD achieved a rapid drying rate,the lack of effective convective airflow led to potential case-hardening and unstable product quality.In contrast,the HAD-IRD strategy demonstrated a synergistic effect.The optimal parameters were determined as follows:hot air temperature of 70℃,infrared temperature of 60℃,and radiation distance of 16 cm.Under these optimized conditions,HAD-IRD reduced the total drying time by over 70%while simultaneously yielding products with superior color,higher sensory scores,and improved rehydration ratio.This study confirms that HAD-IRD is an efficient and high-quality drying method for banana slices,providing a reliable theoretical foundation and technical solution for the drying of thermosensitive fruits.
文摘The design and development of solar dryers are crucial in regions with abundant solar energy,such as Bhopal,India,where seasonal variations significantly impact the efficiency of drying processes.The paper is focused on employing a comprehensive mathematical model to predict the dryer’s performance in drying the materials such as banana slices.To enhance this model,Hyper Tuned Swarm Optimization with Gradient Tree(HT_SOGT)was utilized to accurately predict and determine the optimal size of the dryer dimensions considering various mathematical calculations for material drying.The predictive model considered the influence of seasonal fluctuations,ensuring an efficient drying process with an objective function to optimize the drying time of an average of 7 hrs throughout the year.Across all recorded ambient temperatures(ranging from 16.985○C to 31.4○C),the outlet temperature of the solar dryer is consistently higher,ranging from 39.085○C to 66.2○C.The results show that the optimized dryer design,based on HT_SOGT modelling,significantly improves drying efficiency of the materials across varying conditions,making it suitable for sustainable applications in agriculture and food processing industries in the Bhopal region.
基金supported by the Key-Area Research and Development Program of Guangdong Province(No.2023B0101200006)Guangdong Basic and Applied Basic Research Foundation(No.2024A1515011926)+1 种基金Fund of Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates,Guangzhou 510640,China(South China University of Technology)(No.2023B1212060003)State Key Laboratory of Applied Microbiology Southern China(No.SKLAM008-2022)。
文摘The dynamics of the drying process of polymer solutions are important for the development of coatings and films.In the present work,digital holographic microscopy(DHM)was performed to capture the drying dynamics of poly(ethylene oxide)(PEO)droplets using a gold nanoparticle tracer,where the heterogeneous flow field in different regions was illustrated.This demonstrates that the gold nanoparticles at either the center or the edge regions of the droplet exhibit anisotropic kinematic behavior.At early stage,Marangoni backflow causes gold nanoparticles to move towards the edge firstly,and the circles back towards the droplet center after arriving the contact line with a sudden increase in z axis for 10.4μm,indicating the scale of the upward-moving microscopic flow vortices.This phenomenon does not occur in water droplets in the absence of polymers.The gold nanoparticles underwent Brownian-like motion at the center of the PEO droplet or water droplet owing to the low perturbation of the flow field.At the late stage of pinning of the PEO droplets,the motion showed multiple reverses in the direction of the gold nanoparticles,indicating the complexity of the flow field.This study enhances the understanding of the drying dynamics of polymer solution droplets and offers valuable insights into the fabrication of surface materials.
基金Funded by the National Natural Science Foundation of China project(Nos.52108219 and U21A20150)the Lanzhou University of Technology Hongliu Outstanding Young Talent Program,China(No.04-062407)the Research on Quality Control Technology of High-performance Concrete Prepared by Manufactured Sand(No.2020Y21)。
文摘To study the effects of fine-aggregates on the drying-shrinkage properties of concrete,two types of manufactured-sand and one type of natural sand(excluding<75μm particles)were selected for tests,and nine sets of concrete drying shrinkage tests were designed with three strength grade(C30,C40,and C50)as variables.By observing the drying-shrinkage deformation of the specimens over 360 days,the effects of fine-aggregate properties on the drying shrinkage properties of concrete of different strength grades were analyzed and a prediction model was developed.Compared with natural sand concrete,the development of drying shrinkage of manufactured-sand concrete exhibits the phenomenon of advancement.The apparent density of the fine-aggregate and the strength grade are the two main factors affecting the limit value of the drying shrinkage of concrete.With a reduction in the water absorption or apparent density of the fine-aggregate or the strength grade of concrete prepared using the same fine-aggregate,the prediction accuracy of the existing models decreases.According to the GL 2000 model,two coefficients-and-were introduced to propose a prediction model for the drying shrinkage of fine-aggregate concrete,which is applicable to different strength grades.
基金Supported by the National Natural Science Foundation of China(32072352)。
文摘The low-temperature spray drying technology was developed to process instant berry powder with high efficiency and higher anthocyanin retention.The maltodextrin,whey protein and inulin were selected as additives for instant properties formation in berry powder.The effects of inlet air temperature(40℃–80℃),vacuum degree(0.02–0.06 MPa)and additive amount on the physicochemical properties of berry powder were analyzed through solubility,anthocyanin retention and powder yield,based on moisture content and microstructure.The findings indicated that adding maltodextrin to berry enhanced the powder yield and instant solubility.Whey protein,as an additive,provided effective protection for the anthocyanins of berry powder,and the addition less than 10 g·100^(-1) g improved the powder yield.Inulin,as an additive,reduced moisture content of berry powder,which was conducive to the higher anthocyanin retention and solubility.Technique for order preference by similarity to ideal solution(TOPSIS)analysis was conducted to optimize the spray drying parameters for anthocyanin protection and solubility.The addition of 100%maltodextrin enhanced anthocyanin protection and solubility,while maintaining the desired moisture content and powder yield.This approach was used to evaluate the comprehensive quality of berry powder.This research can provide technical guidance for producing berry powder under low-temperature spray drying.
基金supported by National Natural Science Foundation of China(award no.52408309)National Natural Science Foundation of China(award no.52438002).
文摘Purpose–Severe scarcity of natural river sand(RS),exacerbated by environmental protection policies and extraction constraints,has significantly impacted aggregate supply for railway concrete.While manufactured sand(MS)offers a substitute for RS in railway applications,its widespread adoption in high-strength railway prestressed structures is challenged by lack of drying shrinkage and creep research data on concrete.Design/methodology/approach–High-strength manufactured sand concrete(MSC)was prepared using MS with varying lithologies and stone powder contents.Its drying shrinkage and creep behaviors were evaluated in accordance with the Chinese standard GB/T 50082.The deformation mechanism was analyzed by combining nano-scratch testing.Findings–Compared to RS concrete,MSC from all tested lithologies showed higher drying shrinkage but lower creep deformation.The drying shrinkage rose steadily with increased stone powder content,while the creep strain displayed a distinct non-linear trend,decreasing first before rising.To prepare low-deformation MSC,select high-strength MS and limit stone powder content not greater 10%.Nano-scratch tests indicated that harder MS particles suppress microcracking at the interfacial transition zone(ITZ),improving the creep resistance.The predictive models for drying shrinkage and creep were also developed by incorporating coefficients for stone powder and lithology effects.Originality/value–These findings serve as a foundation for the application of MSC in railway prestressed structures,offering both theoretical and practical guidance.
基金National Research Council of Thailand(NRCT)and the School of Renewable Energy and Maejo University for the project to produce and develop graduates in renewable energy for ASEAN countries for graduate students(2021).
文摘This work investigates a combined cooling,heating,and power(CCHP)generation system utilizing waste energy.A cascade-CCHP system is developed,consisting of a 23.65-kWe organic Rankine cycle(ORC),a 4.00-kW adsorption chiller,a 4.11-kW absorption chiller,a 15.99-kW drying room,and an incinerator of 150 kg/h.A net energy production of 36.08 kWh is achieved from a CCHP energy efficiency of 9.98%.The levelized cost for producing a total energy output of 2,020,592 kWh over a lifespan of 20 years is approximately 0.106 USD/kWh.The life cycle assessment(LCA)yields a single score of approximately 0.000151 Pt,mainly attributed to raw materials used in the construction process of 87.16%.In addition,the combustion ash is processed into concrete blocks measuring 39 cm×19 cm×7 cm,in accordance with the Industrial Product Standard(TIS)58-2533,with a water absorption value below 5%and a compressive strength exceeding 25 kg/cm2.The CCHP system demonstrates a novel method of waste-to-energy(WtE),and the construction material from waste combustion ash can also support a new concept of waste-to-zero(WtZ).
基金funded by the Water Research Commission through the grant K5/2582 and the Gates Foundation through the grant OPP1170678.
文摘Onsite sanitation offers a sustainable alternative to centralized wastewater treatment;however,effective faecal sludge management is crucial for safe disposal and resource recovery.Among emerging treatment solutions,solar thermal drying holds significant promise to reduce sludge moisture content and enhance handling.Despite this potential,its application remains limited,with important knowledge gaps,particularly concerning the drying kinetics under different environmental and operational conditions.This study aims to fill these gaps by investigating the solar thermal drying behaviour of faecal sludge from ventilated improved pit latrines(VIPs)and urine-diverting dry toilets(UDs),with a specific focus on how air temperature and velocity influence drying performance.A bench-scale solar drying apparatus was used to investigate thin-layer sludge drying kinetics under controlled airflow conditions.The drying experiments were conducted at varying air temperatures(ambient,40℃,and 80℃)and velocities(0,0.5,and 1 m/s),where heated air was supplied via an electric resistance heater.Key drying parameters-including drying rate,critical moisture content,effective moisture diffusivity,and activation energy-were determined.Results showed that drying proceeded through a constant-rate period followed by a falling-rate period,with the critical moisture content ranging from 1.41 to 1.78 g/g db.Higher temperatures and airflow reduced the duration of the constant-rate phase,increased drying rates(0.31–0.99 g/g·min·m^(2)),and enhanced moisture diffusivity(4.56×10^(−9) to 1.52×10^(−8) m^(2)/s).Activation energy decreased with increased airflow,suggesting reduced temperature sensitivity.Thermal efficiency ranged from 14.6%to 35.1%,with solar energy contributing 73%–95% of total input.VIP sludge dried faster than UD sludge,which showed signs of surface crusting that limited moisture transfer.This research offers valuable insights into solar drying design and operation,providing scientific evidence to improve faecal sludge treatment strategies in decentralized sanitation systems.
文摘The effect of a storage system on drying time and estimation of drying parameters of cocoa beans using an indirect solar dryer with a sensible heat energy storage system (stones which act as both absorber and heat storage media) is the main subject of this article. This dryer, which uses stones as storage material and is made of wood and plywood, was used to dry a quantity of 5 kg of fermented cocoa beans. The drying parameters for the drying curves and the drying efficiency of cocoa beans were established and studied. The drying curves were modelled from semi-empirical models. The results showed that the moisture of cocoa beans decreased from 60% to 7% in wet basis. With a solar collector and drying efficiency of 40% and 34%, respectively. And this with a maximum average difference temperature between the drying air and the ambient temperature of 13.25˚C day or night. The best concordances are obtained with R2 values of 0.9983, 0.9843, 0.9813 and 0.9837 respectively from the models of Hii, Jena and Das, Demir et al. and Alibas.
基金Project(41877240)supported by the National Natural Science Foundation of China。
文摘As a typical sedimentary soft rock,mudstone has the characteristics of being easily softened and disintegrated under the effect of wetting and drying(WD).The first cycle of WD plays an important role in the entire WD cycles.X-ray micro-computed tomography(micro-CT)was used as a non-destructive tool to quantitatively analyze microstructural changes of the mudstone due to the first cycle of WD.The test results show that WD leads to an increase of pore volume and pore connectivity in the mudstone.The porosity and fractal dimension of each slice of mudstone not only increase in value,but also in fluctuation amplitude.The pattern of variation in the frequency distribution of the equivalent radii of connected,isolated pores and pore throats in mudstone under WD effect satisfies the Gaussian distribution.Under the effect of WD,pores and pore throats with relatively small sizes increase the most.The sphericity of the pores in mudstones is positively correlated with the pore radius.The WD effect transforms the originally angular and flat pores into round and regular pores.This paper can provide a reference for the study of the deterioration and catastrophic mechanisms of mudstone under wetting and drying cycles.
基金supported by the National Key Research and Development Program of China(2019YFA0705800)the National Natural Science Foundation of China(52030001)the Science&Technology Commission of Shanghai Municipality(20dz1207600).
文摘Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a large amount of thermal energy to conquer the phase-change latent heat of moisture.Herein,we report a non-phase change technology based on particle high-speed self-rotation in a cyclone for fast,low-temperature drying of viscous sludge with high-moisture contents.Dispersed phase medium(DPM)is introduced into the cyclone self-rotation drying(CSRD)reactor to enhance the dispersion of the viscous sludge.The effects of carrier gas temperature,feeding rate,size,and proportion of DPM particles in the drying process are systematically examined.Under optimal operating conditions,the weighted content of moisture in the viscous sludge could be reduced from 80%to 15.01%in less than 5 s,achieving a high drying efficiency of 95.79%.Theoretical calculations also reveal that 89.26%of the moisture is removed through non-phase change pathway,contributing to a 522-fold increase in the drying rate of CSRD compared to TED technology.This investigation presents a sustainable effective approach for high moisture viscous sludge treatment with low energy consumption and carbon emissions.
文摘Côte d’Ivoire has been the world’s leading producer of cocoa beans for several decades. Apart from this production performance, the quality of the beans, which are mainly exported to the major chocolate-making countries, presents a quality problem to the point of suffering a discount on the international market. One of these quality problems is the content of ochratoxin A, a mycotoxin produced by fungi. Finally, to verify the level of contamination in beans produced in Côte d’Ivoire, a study was carried out. It consisted of collecting information on fermentation and drying times (The two major post-harvest operations) and collecting beans, which were analyzed by electrophoresis using the High Performance Liquid Chromatography (HPLC) method. The results obtained show ochratoxin A contents of between 0.05 µg/kg and 0.17 µg/kg. The general level of contamination is therefore very low and below the tolerable limit which is 2 µg/kg. In addition, the correlative study between the fermentation and drying times of the beans revealed no significant influence (p < 0.01) of the duration of these operations on the level of ochratoxin A contamination. Major contamination can occur after post-harvest activities carried out by producers. This is certainly due to the development of fungi responsible for the production of ochratoxin A during the period of storage and marketing of cocoa beans in conditions of high humidity in storage enclosures. Producers need to be made more aware of the need to ensure that cocoa beans are properly dried and stored in dry areas to avoid moisture build-up, which is a source of mould growth and ochratoxin A production.
文摘The aim of this paper was to characterize through experiment the moisture and temperature kinetic behavior of Eucalyptus gomphocephala wood samples using microwave heating(MWH)in two scenarios:intermittently and continuously.The mechanical properties and surface appearance of the heated samples were also investigated.Continuous and intermittent microwave drying kinetic experiments were conducted at a frequency of 2.45 GHz using a microwave laboratory oven at 300,500,and 1000 watts.Drying rate curves indicated three distinct phases of MWH.Increasing the microwave power with a shorter drying time led to rapid increases in internal temperature and water evaporation rates of the heated samples.Mechanical results indicated that samples heated under continuous MW(Microwave)power at 300 watts had a modulus of rupture(MOR)and modulus of elasticity(MOE)in three static bending tests higher than 29%and 36%,respectively,than samples heated at 1000 watts.Intermittent microwave heating(IMWH)of samples at 300 and 1000 watts produced the highest MOR and MOE values of 31%and 51%,respectively,unlike those heated under continuous microwave heating(CMWH).External qualitative observation showed that samples heated at high microwave power had severe surface checks.These defects were missing when using IMWH.An analysis of variance(ANOVA)showed that mechanical properties were linked to both microwave power level and the heating scenario,except for MOR in axial compression under CMWH.
基金supported by the Natural Science Foundation of Jiangsu Province,China(BK20241931 and BK20221371)the National Natural Science Foundation of China(32071943 and 32372214)the National Key Research and Development Program of China(2022YFD2300304)。
文摘Alternate wetting and soil drying irrigation(AWD)technique is crucial in infuencing grain quality in rice(Oryza sativa L.).Lipids are the third most abundant constituents in rice grains,after starch and proteins,and are closely related to grain quality.However,it remains unclear about the changes in lipids profling under different AWD regimes.This study set up three irrigation regimes including conventional irrigation(CI),alternate wetting and moderate soil drying irrigation(AWMD),and alternate wetting and severe soil drying irrigation(AWSD).It explored lipidome changes in milled rice of Yangdao 6(YD6)using the untargeted lipidomics approach and analyzed rice cooking and eating quality.The results identifed seven lipid classes,55 lipid subclasses,and 1,086 lipid molecular species.Compared with the CI regime,the AWMD regime mainly altered lipid subclasses consisting of triglyceride(TG),ceramide(Cer),diglyceride(DG),bis-methyl lysophosphatidic acid(BisMePA),phosphocholine(PC),phosphoethanolamine(PE),monogalactosyldiacylglycerol(MGDG),and digalactosyl diglyceride(DGDG)in milled rice and improved cooking and eating quality of rice;in contrast,the AWSD regime distinctly changed lipid subclasses like TG,Cer,DG,PC,PE,hexosylceramide(Hex1Cer),DGDG,and BisMePA and degraded cooking and eating quality of rice.Specifcally,AWMD most signifcantly altered the expressions of lipid molecules,including DGDG(18:0_18:2),DGDG(16:0_14:0),PC(33:1),Cer(t17:0_26:0),and Cer(t17:0_16:0);AWSD most obviously influenced the expressions of TG(6:0_14:0_18:3),PC(41:1),TG(19:1_18:4_18:4),Hex1Cer(d18:2_24:0+O),and Hex1Cer(d18:2_24:1).These 10 altered lipid molecules in milled rice can be preferentially used for investigating their relationships with grain quality in rice.
