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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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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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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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An integrated strategy of UPLC-Q-TOF/MS and HPTLC/PAD-DESI-MSI for the analysis of chemical variations:A case study of Tibetan medicine Tiebangchui
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作者 Yue Liu Mengjia Li +2 位作者 Xing Fu Yi Zhang Ce Tang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期615-618,共4页
The dried roots of Aconitum pendulum Busch are the major source of a commonly used Tibetan medicine,namely Tiebangchui(TBC)(Fig.S1).However,raw TBC contains a large amount of high toxic diester-diterpenoid alkaloids(D... The dried roots of Aconitum pendulum Busch are the major source of a commonly used Tibetan medicine,namely Tiebangchui(TBC)(Fig.S1).However,raw TBC contains a large amount of high toxic diester-diterpenoid alkaloids(DDAs),and the improper use would cause arrhythmia,irreversible cardiovascular damages,and even death.“Paozhi”,an appropriate processing method,is the essential prerequisite for the safe clinical application of TBC.Water-decocting and sand-frying are commonly used processing methods for toxicity attenuation and efficacy preservation for TBC. 展开更多
关键词 DRIED IRREVERSIBLE ROOTS
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Combined application of organic fertilizer and chemical fertilizer alleviates the kernel position effect in summer maize by promoting post-silking nitrogen uptake and dry matter accumulation
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作者 Lichao Zhai Lihua Zhang +7 位作者 Yongzeng Cui Lifang Zhai Mengjing Zheng Yanrong Yao Jingting Zhang Wanbin Hou Liyong Wu Xiuling Jia 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1179-1194,共16页
Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CA... Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CAOFCF)can alleviate the kernel position effect of summer maize,field experiments were conducted during the 2019 and 2020 growing seasons,and five treatments were assessed:CF,100%chemical fertilizer;OFCF1,15%organic fertilizer+85%chemical fertilizer;OFCF2,30%organic fertilizer+70%chemical fertilizer;OFCF3,45%organic fertilizer+55%chemical fertilizer;and OFCF4,60%organic fertilizer+40%chemical fertilizer.Compared with the CF treatment,the OFCF1 and OFCF2 treatments significantly alleviated the kernel position effect by increasing the weight ratio of inferior kernels to superior kernels and reducing the weight gap between the superior and inferior kernels.These effects were largely due to the improved filling and starch accumulation of inferior kernels.However,there were no obvious differences in the kernel position effect among plants treated with CF,OFCF3,or OFCF4 in most cases.Leaf area indexes,post-silking photosynthetic rates,and net assimilation rates were higher in plants treated with OFCF1 or OFCF2 than in those treated with CF,reflecting an enhanced photosynthetic capacity and improved postsilking dry matter accumulation(DMA)in the plants treated with OFCF1 or OFCF2.Compared with the CF treatment,the OFCF1 and OFCF2 treatments increased post-silking N uptake by 66.3 and 75.5%,respectively,which was the major factor driving post-silking photosynthetic capacity and DMA.Moreover,the increases in root DMA and zeatin riboside content observed following the OFCF1 and OFCF2 treatments resulted in reduced root senescence,which is associated with an increased post-silking N uptake.Analyses showed that post-silking N uptake,DMA,and grain yield in summer maize were negatively correlated with the kernel position effect.In conclusion,the combined application of 15-30%organic fertilizer and 70-85%chemical fertilizer alleviated the kernel position effect in summer maize by improving post-silking N uptake and DMA.These results provide new insights into how CAOFCF can be used to improve maize productivity. 展开更多
关键词 chemical fertilizer dry mater accumulation kernel position effect N uptake organic fertilizer
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Dry eye disease in systemic lupus erythematosus: a cross sectional study
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作者 Sui-Fang Kang Ying-Xue Wang +2 位作者 Qi-Chen Zhang Zhi-Lun Wang Guo-Ling Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第7期1255-1261,共7页
AIM:To explore ocular surface manifestations of dry eye disease(DED)and its influencing factors in systemic lupus erythematosus(SLE)patients.METHODS:Ophthalmological examinations were conducted in SLE patients(n=43)an... AIM:To explore ocular surface manifestations of dry eye disease(DED)and its influencing factors in systemic lupus erythematosus(SLE)patients.METHODS:Ophthalmological examinations were conducted in SLE patients(n=43)and controls(n=41),including Ocular Surface Disease Index(OSDI),objective scatter index(OSI),tear meniscus height(TMH),lipid layer thickness(LLT),non-invasive Keratograph tear breakup time(NIKBUT),corneal fluorescein score(CFS),Schirmer I test.DED was diagnosed according to the Tear Film and Ocular Surface Society Dry Eye Workshop II Criteria.SLE patients were further divided into DED group and non-DED group,the disease activity,clinical manifestations and laboratory investigations were compared between the two groups.The disease activity was evaluated by Systemic Lupus Erythematosus Disease Activity Index 2000(SLEDAI-2K).Receiver operative characteristic(ROC)curve and multiplefactor binary logistic regression were performed.RESULTS:SLE patients showed higher OSDI[9.1(2.8-15.9)vs 6.3(2.2-7.5),P=0.035],higher OSI[1.67(1.09-2.60)vs 0.96(0.87-1.60),P=0.001],higher CFS[1(0-2)vs 0(0-1),P=0.001],lower LLT[65(42-100)vs 100(79.5-100),P=0.010],and lower NIKBUT[8.03(4.02-9.73)vs 9.67(5.26-12.71),P=0.030]than controls.The 32.6%of SLE patients had DED,which was higher than 12.2%of healthy controls.DED group showed higher SLEDAI-2K score[9.7±6.1 vs 5.4±3.4,P=0.025],higher anti-cardiolipin antibody(ACL)[8.7(3.5-13.2)vs 3.6(2.0-6.9),P=0.035],and higher proportion of patients with cutaneous eruption[42.9%vs 6.9%,P=0.015]than non-DED group.According to multiple-factor binary logistic regression analysis,the SLEDAI-2K score(OR=1.194,P=0.041)and cutaneous eruption(OR=7.094,P=0.045)could be consider as risk factors for DED in SLE patients.The ROC curve of the combined factors including age,disease duration,SLEDAI-2K score,ACL,and cutaneous eruption was analyzed,with a sensitivity of 0.786,a specificity of 0.793,and an area under curve of 0.820.CONCLUSION:Ocular surface affection is frequent in SLE patients,and patients with high disease activity and cutaneous eruption show increased risk of DED. 展开更多
关键词 autoimmune disease systemic lupus erythematosus dry eye disease
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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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The Role of the Size Effect on the Drying of Refractory Castables—How Its Under-standing Could Narrow the Gap between Laboratory Studies and Industrial Reality
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作者 M.H.MOREIRA H.PENG +1 位作者 S.Dal PONT V.C.PANDOLFELLI 《China's Refractories》 CAS 2024年第2期35-40,共6页
Refractories have unique capabilities such as sustaining their shape and properties at extreme conditions such as the combination of high temperatures and thermal shock,contact with molten metals and slags and in some... Refractories have unique capabilities such as sustaining their shape and properties at extreme conditions such as the combination of high temperatures and thermal shock,contact with molten metals and slags and in some circumstances resistance to erosion from abrasive particles.Given the large processing output of the heavy industries such as the cement and steel ones which both require high temperature processes,the refractories structures span various meters and weight of several tons.As the water removal stage of hydraulic bonded castables in industrial sites takes hours(10-60 h)due to the risk of explosive spalling,efforts to mitigate it are commonly studied.This has provided theoretical understanding of the general aspects of drying and important tools,such as the thermogravimetry analysis(TGA),for the design of refractory compositions with higher explosive spalling resistance.However,the optimization of this process is still far from the industrial reality especially because the actual linings that require the drying are orders of magnitude larger than the samples considered in the laboratory tests.Therefore,this study proposed the analysis of the sample volume effect on the water removal dynamics through TGA of high alumina castables with calcium aluminate cement.Conventionalφ5 cm×5 cm cylindrical samples were assessed in a laboratory scale equipment whereas macro TGA were carried out considering 20 cm×20 cm×20 cm and 30 cm×30 cm×30 cm cubic samples.Additionally,the effect of polymeric fibers was also considered.It was found out that the different thermal gradients within the macro TGA samples resulted in an inflection on the sample’s heating rate and that the mass loss was affected by the volume considered,especially for the composition without additives.These findings highlight the requirement of carefully taking into consideration the different dimensional sizes and thermal gradients in the samples when analyzing and interpreting the laboratory studies,and especially when trying to extrapolate such results to the industrial reality. 展开更多
关键词 drying refractory castables size effect thermogravimetry analysis
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Effect of Supplementary Irrigation on the Yield of Sorghum (Sorghum bicolor L. Moench) in the Context of Climate Change in the Dry Savannahs of Togo
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作者 Adjiwanou Atiglo-Gbenou Yaovi Ouézou Azouma Jean Mianikpo Sogbedji 《American Journal of Climate Change》 2024年第2期163-174,共12页
Under the current context of climate change, supplementary irrigation may be needed for crop production resilience. We determined the effects of supplementary irrigation on sorghum grain yield in the dry Savannah regi... Under the current context of climate change, supplementary irrigation may be needed for crop production resilience. We determined the effects of supplementary irrigation on sorghum grain yield in the dry Savannah region of Togo. A two-year trial was conducted in a controlled environment at AREJ, an agro-ecological center in Cinkassé. The plant material was sorghum variety Sorvato 28. The experimental design was a Completely Randomized Block with three replications and three treatments as follows: T0 control plot (rainfed conditions);T1 (supplementary irrigation from flowering to grain filling stage) and T2 (supplementary irrigation from planting to grain filling stage). Two irrigation techniques (furrow and Californian system) were used under each watering treatment. The results showed that irrigation technique significantly affected panicle length with no effect on 1000 grains mass. Panicle length and grain yields varied from 15.59 to 25.71 cm and 0.0 to 2.06 t∙h−1, respectively, with the highest values (25.66 cm and 2.06 t∙h−1, respectively) under the T2 treatment with the California system-based supplementary irrigation. The comparison of results obtained on treatment T0 and T2, shows that supplementary irrigation increased the yields by at least 68.62%. Supplementary irrigation during sowing and growing season (T2) improved sorghum yields in the dry savannahs of Togo, with a better performance of the California irrigation system. 展开更多
关键词 Climate Change Supplementary Irrigation Sorghum Grain Yield Dry Savannah TOGO
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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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Grain yield and water use efficiency of super rice under soil water deficit and alternate wetting and drying irrigation 被引量:25
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作者 ZHOU Qun JU Cheng-xin +4 位作者 WANG Zhi-qin ZHANG Hao LIU Li-jun YANG Jian-chang ZHANG Jian-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第5期1028-1043,共16页
This study investigated if super rice could better cope with soil water deficit and if it could have better yield performance and water use efficiency (WUE) under alternate wetting and drying (AWD) irrigation than... This study investigated if super rice could better cope with soil water deficit and if it could have better yield performance and water use efficiency (WUE) under alternate wetting and drying (AWD) irrigation than check rice. Two super rice cultivars and two elite check rice cultivars were grown in pots with three soil moisture levels, well watered (WW), moderate water deficit (MWD) and severe water deficit (SWD). Two cultivars, each for super rice and check rice, were grown in field with three irrigation regimes, alternate wetting and moderate drying (AWMD), alternate wetting and severe drying (AWSD) and conventional irrigation (CI). Compared with that under WW, grain yield was significantly decreased under MWD and SWD treatments, with less reduction for super rice than for check rice. Super rice had higher percentage of productive tillers, deeper root distribution, higher root oxidation activity, and greater aboveground biomass production at mid and late growth stages than check rice, especially under WMD and WSD. Compared with CI,AWMD increased, whereasAWSD decreased grain yield, with more increase or less decrease for super rice than for check rice. Both MWD and SWD treatments and eitherAWMD orAWSD regime significantly increased WUE compared with WW treatment or CI regime, with more increase for super rice than for check rice. The results suggest that super rice has a stronger ability to cope with soil water deficit and holds greater promising to increase both grain yield and WUE by adoption of moderate AWD irrigation. 展开更多
关键词 super rice soil water deficit alternate wetting and drying (AWD) grain yield water use efficiency
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Influence of Superplasticizer Type and Dosage on Early-age Drying Shrinkage of Cement Paste with Consideration of Pore Size Distribution and Water Loss 被引量:2
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作者 钱晓倩 YU Congdi +3 位作者 ZHANG Lifeng QIAN Kuangliang FANG Minghui LAI Junying 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第4期758-767,共10页
We introduced a parameter r_s(the radius of the pores where the meniscus forms),which is composed of two factors,i e,water loss and cumulative pore size distribution(PSD),to provide a better explanation of the influen... We introduced a parameter r_s(the radius of the pores where the meniscus forms),which is composed of two factors,i e,water loss and cumulative pore size distribution(PSD),to provide a better explanation of the influence of superplasticizers(SPs)on early-age drying shrinkage.In our experiments,it is found that the addition of three types of SPs leads to a significant increase in the early-age drying shrinkage of cement paste,and drying shrinkage increases with the dosage of SPs.Based on the results above,we further studied the mechanism of the effects of SPs on the early-age drying shrinkage of cement paste by PSD and water loss,which are two components of r_s.The experimental results indicate that r_s can be a better index for the early-age drying shrinkage of cement-based materials with SPs than a single factor.In addition,the effects of SPs on other factors such as hydration degree and elastic modulus were also investigated and discussed. 展开更多
关键词 SupERPLASTICIZER early-age drying shrinkage water loss pore size distribution
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Synthesis of Ti-Ce-Si Binary and Ternary Nanocomposite Photocatalyst by Supercritical Fluid Drying Technology 被引量:2
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作者 张敬畅 高玲玲 曹维良 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第2期182-187,共6页
Ti-Ce, Ti-Si binary and Ti-Ce-Si ternary novel nanocomposite oxide photocatalysts were prepared with cheap inorganic salts TiCI4, Na2SiO3·9H2O and Ce(NO3)3·6H2O as precursors by supercritical fluid drying ... Ti-Ce, Ti-Si binary and Ti-Ce-Si ternary novel nanocomposite oxide photocatalysts were prepared with cheap inorganic salts TiCI4, Na2SiO3·9H2O and Ce(NO3)3·6H2O as precursors by supercritical fluid drying (SCFD) technology. The catalysts were characterized by means of XRD and TEM. The particle size of nanocomposite oxide photocatalysts synthesized by SCFD method is about 6 - 11 nm, which is smaller than those obtained by common drying method (CD). The phase transformation from anatase to rutile was inhibited by SCFD technology. The peaks of SiO2 and CeO2 in XRD patterns indicate that a SiO2 amorphorous phase exists in all the samples and CeO2 is well dispersed on the surface of TiO2. The orthogonal test was designed to optimize the preparing conditions. It is found that ceria dop;.ng enhances the photocatalyric activity markedly, and the optimum doping of CeO2 is 0.1%. The thermal stability of photocatalyst can be improved ; the growth of particle-size and the decrease of surface area can be prohibited by doping of SlOe. Heat-treatment is a necessary factor to induce chemistry change of Ti-Si surface. The optimum heat-treating temperature is 600℃. A novel and efficient Ti-Ce-Si ternary nanocomposite was prepared by SCFI) method with strong thermal stability and high photoactivity in the photodegratation of phenol. 展开更多
关键词 TITANIA SILICA CERIA nanocomposite photocatalysts supercritical fluid dried rare earths
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Synthesis and Characterization of TiO_2-CeO_2 Nanocomposite by Supercritical Fluid Drying 被引量:2
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作者 张敬畅 高玲玲 曹维良 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第S1期134-137,共4页
TiO_2-CeO_2 nanocomposite particles were prepared with Ce(NO_3)_3·6H_2O and TiCl_4 as precursors by the codeposition method and supercritical fluid drying (SCFD) technology. The particles prepared were characteri... TiO_2-CeO_2 nanocomposite particles were prepared with Ce(NO_3)_3·6H_2O and TiCl_4 as precursors by the codeposition method and supercritical fluid drying (SCFD) technology. The particles prepared were characterized by means of XRD, TEM and FTIR. The results show that SCFD can give rise to the direct synthesis of the anatase TiO_2-CeO_2,and the particle size is 6~11 nm under 500 ℃ thermal-treated,smaller than that by common drying (CD). The phase transformation from anatase to rutile is inhibited by supercritical fluid drying technology. The peak of CeO_2 is not observed in XRD patterns,Ce-O band vibration was present in FTIR spectrum,which indicates that CeO_2 is well dispersed on the surface of TiO_2. 展开更多
关键词 TITANIA CERIA supercritical fluid dried NANOCOMPOSITE rare earths
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Influence of Superplasticizers on Early Age Drying Shrinkage of Cement Paste with the Same Consistency 被引量:3
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作者 赖俊英 ZHANG Lifeng +2 位作者 钱晓倩 SHEN Chong ZHANG Jinjian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第6期1201-1207,共7页
The influence of superplasticizer(SP) on the early age drying shrinkage of cement paste with the same consistency was investigated. To conduct the test, which lasted for 72 hours, three paste mixtures were used for ... The influence of superplasticizer(SP) on the early age drying shrinkage of cement paste with the same consistency was investigated. To conduct the test, which lasted for 72 hours, three paste mixtures were used for comparison. The 72 hours early age drying shrinkage staring from the initial setting time was measured by a clock gauge. The pore size distribution was measured by Mercury Intrusion Method. The surface tension of capillary simulation liquid and mass loss of paste were also measured. The experimental results showed that the addition of SP increased the early drying shrinkage greatly. The ratios of water evaporation and the total free water in mixtures added with SPs showed great differences. SPs fined the capillary pores of paste, and the volume of pore with diameter within 50 nm was well consistent with shrinkage rate. The addition of SPs did not raise the capillary liquid surface tension. It showed that with the volume of pore with diameter within 50 nm and the ratio of water evaporation and the total free water a tolerable shrinkage result of paste added with SP could be predicted, and the elastic modulus could have an influence on the early shrinkage. These results have never been proposed before. 展开更多
关键词 superplasticizer early age drying shrinkage paste water evaporation pore size distribution
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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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