The engineering profession has responded to the issue of sustainable development in two main ways. It has responded through public policy statements that acknowledge the magnitude of the problem in addition to pledgin...The engineering profession has responded to the issue of sustainable development in two main ways. It has responded through public policy statements that acknowledge the magnitude of the problem in addition to pledging to steer engineering towards a more sustainable future, and it has also responded more directly through technological innovation. In this paper, these two responses will be explored with respect to the debate on how to operationalize sustainability principles in practical terms. This paper also attempts to provide the rationale for a philosophy of engineering ethics grounded in the notion of sustainable development. It is hoped that this would lead to a revised “social contract” that would enable engineers to engage more actively in political, technical, economic and social discussions and processes.展开更多
This study explores the broad-spectrum application of OsRALF26,a small secreted peptide belonging to the rapid alkalinization factor(RALF)family in rice.We found that the rice genome carries numerous lineage-specific ...This study explores the broad-spectrum application of OsRALF26,a small secreted peptide belonging to the rapid alkalinization factor(RALF)family in rice.We found that the rice genome carries numerous lineage-specific OsRALFs,suggesting that this evolutionary expansion could be the result of an arms race with pathogens.Among them,we focused on the Oryza-specific Os RALF26 and its closest homolog,OsRALF27,analyzing their effects across a range of plant species from monocots to dicots.The exogenous application of OsRALF26 significantly reduced bacterial populations in rice challenged with Xanthomonas oryzae pv.oryzae(Xoo)and in Arabidopsis and tomato challenged with Pseudomonas syringae pv.tomato DC3000(Pst DC3000),whereas Os RALF27 did not enhance resistance.展开更多
Irrigation methods and nitrogen(N) fertilization modes have complicated impacts on wheat physiology, growth, and development, leading to the regulation of wheat grain yield and quality. However, the optimal water-N co...Irrigation methods and nitrogen(N) fertilization modes have complicated impacts on wheat physiology, growth, and development, leading to the regulation of wheat grain yield and quality. However, the optimal water-N combination for drip-irrigated winter wheat remains unclear. A two-year field study was conducted to evaluate the influences of various N-fertigation and water regimes on wheat post-anthesis grain weight variation, yield, grain NPK content, and grain quality. The two irrigation quotas were I_(45)(irrigation when crop evapotranspiration reduced by effective rainfall(ETa-P) reaches 45 mm) and I_(30)(irrigation when ETa-P reaches 30 mm), while the six N application rates were N_(0–100)(100% at jointing/booting), N_(25–75)(25% at sowing and 75% at jointing/booting), N_(50–50)(50% at sowing and 50% at jointing/booting), N_(75–25)(75% at sowing and 25% at jointing/booting), N_(100–0)(100% at sowing), and SRF100(100% of slow-release fertilizer at sowing). The experimental findings showed that post-anthesis grain weight variation, grain yield, grain NPK content, and grain quality were all markedly influenced by the various irrigation schedules and N-fertilization modes. The N_(50–50)treatment was more beneficial for winter wheat post-anthesis grain weight variation than the N_(100–0)and N_(0–100)treatments under the two irrigation quotas and during the two seasons. The highest grain yields of 9.72 and9.94(t ha^(-1)) were obtained with the I_(45)N_(50–50)treatment in 2020–2021 and 2021–2022, respectively. The grain crudeprotein was higher in the I_(45)SRF100treatment during the two seasons. The I_(45)N_(100–0)combination significantly(P<0.05)enhanced the content of grain total starch by 7.30 and 8.23% compared with the I_(45)N_(0–100)and I_(30)N_(0–100)treatments,respectively, during the 2021–2021 season. The I_(45)N_(100–0)treatment significantly(P<0.05) enhanced the content ofgrain total starch concentration by 7.77, 7.62 and 7.88% compared with the I_(45)N_(0–100), I_(30)N_(0–100), and I_(30)N_(25–75)treatments,respectively, in the 2021–2022 season. The principal component analysis(PCA) indicated that the N_(50–50)splitN-fertigation mode could be the optimal choice for farmers during winter wheat production via drip irrigation.展开更多
The demand for flexible electric heating devices has increased due to technology advancement and improved living standards.These devices have various applications including personal thermal management,hyperthermia,def...The demand for flexible electric heating devices has increased due to technology advancement and improved living standards.These devices have various applications including personal thermal management,hyperthermia,defrosting,agricultural heating film,and oil-water separation.Joule heat,generated by electric currents,is commonly used in electrical appliances.To incorporate Joule heating into flexible electronics,new materials with excellent mechanical properties are necessary.Traditional polymers,used as reinforcements,limit the continuity of conductive networks in composites.Therefore,there is a need to develop flexible Joule thermal composite materials with enhanced mechanical strength and conductivity.Cellulose,a widely available renewable resource,is attracting attention for its excellent mechanical properties.It can be used as a dispersant and reinforcing agent for conductive fillers in cellulose-based composites,creating highly conductive networks.Various forms of cellulose,such as wood,nanocellulose,pulp fiber,bacterial cellulose,cellulose paper,textile clothing,and aramid fiber,have been utilized to achieve high-performance Joule thermal composites.Researchers have achieved excellent mechanical properties and developed efficient electric heating devices by designing cellulose-based composites with different structures.The scalable production methods enable large-scale application of cellulose-based devices,each with unique advantages in 1D,2D,and 3D structures.This review summarizes recent advancements in cellulose-based Joule thermal composites,providing insights into different structural devices,and discussing prospects and challenges in the field.展开更多
在玉米-大豆轮作系统中种植冬季覆盖作物黑麦有助于减小地下排水量和硝态氮(NO_3^--N)的流失量。该研究利用美国爱荷华州的试验数据校正和验证了DRAINMOD-N II模型在美国寒冷地区的适用性,并模拟长期(20 a)种植冬季覆盖作物黑麦对地下...在玉米-大豆轮作系统中种植冬季覆盖作物黑麦有助于减小地下排水量和硝态氮(NO_3^--N)的流失量。该研究利用美国爱荷华州的试验数据校正和验证了DRAINMOD-N II模型在美国寒冷地区的适用性,并模拟长期(20 a)种植冬季覆盖作物黑麦对地下排水量和氮素运移的影响。结果表明,模型模拟地下排水量和NO_3^--N流失量时,Nash-Sutcliffe模型效率系数(Nash-Sutcliffe efficiency,NSE)>0.65、百分比偏差(percent bias,PBIAS)在±25%之间、均方根误差与标准差比值(ratio of root mean square error to standard deviation,RSR)≤0.7均在误差范围内;模拟地下排水中NO_3^--N浓度时,NSE>0.50、PBIAS在±15%之间、RSR≤0.5均在误差范围内,说明模型模拟的效果好。长期种植冬季覆盖作物黑麦可降低排水量8.1%(2.5 cm),减小NO_3^--N流失量16.6%(6 kg/hm^2),NO_3^--N流量加权平均浓度下降了8.6%(1 mg/L,以N计),增加蒸散值5.9%,模型模拟值与实测值拟合效果好,表明模型具有良好的水文和氮素运移模拟功能,可以模拟不同农田管理措施对地下水和氮素运移的长期影响,为优化农田管理措施提供参考。展开更多
Presence of fine dust in air causes serious health hazard for mine operators resulting in such serious problems as coal workers’pneumoconiosis and silicosis.Major sources of dust appear of course along the mining fac...Presence of fine dust in air causes serious health hazard for mine operators resulting in such serious problems as coal workers’pneumoconiosis and silicosis.Major sources of dust appear of course along the mining face where the minerals are extracted.Proper control and management are required to ensure safe working environment in the mine.Here,we utilize the computational fluid dynamic(CFD)approach to evaluate various methods used for mitigating dust dispersion from the mining face and for ensuring safe level of dust concentration in the mine tunnel for safety of the operators.The methods used include:application of blowing and exhaust fans,application of brattice and combination of both.The results suggest that among the examined methods,implementation of appropriately located brattice to direct the flow from the main shaft to the mining face is the most effective method to direct dust particles away from the mining face.展开更多
The feasibility of using two types of biochars to reduce steroid hormone pollution from poultry and swine manure application on agricultural land was evaluated. The sorption affinity and desorption resistance of softw...The feasibility of using two types of biochars to reduce steroid hormone pollution from poultry and swine manure application on agricultural land was evaluated. The sorption affinity and desorption resistance of softwood and hardwood biochars were also determined for two estrogen hormones, 17β-estradiol （E2） and its primary metabolite estrone （E1）. The softwood and hardwood biochars demonstrated high retention capacity for both estrogens. The effective distribution coefficient （Kedff） of soil-softwood-derived biochar （SBS450） was significantly higher than soil-hardwood-derived biochar （SBH750）, indicating the stronger sorption affinity of SBS450 for estrogens. To validate the laboratory results, a field lysimeter experiment was conducted to study the fate and transport of E2 and E1 in soil and leachate in the presence of 1% softwood-biochar （BS450） in topsoil and to compare it with soil without any amendments. The spatio-temporal distribution of both estrogens was monitored at four depths over a 46-day period. The lysimeters, in which the surface layer of soil was amended with biochar, retained significantly higher concentrations of both estrogen hormones. Although they leached through the soil and were detected in leachates, collected at 1.0 m depth, the concentrations were significantly lower in the leachate collected from biochar-amended lysimeters. The result confirmed the efficacy of biochar amendment as a remediation technique to alleviate the manure-borne hormonal pollution of groundwater.展开更多
Excessive application of nitrogen (N) fertilizer is the main cause of N loss and poor use efficiency in winter wheat (Triticum aestivum L.) production in the North China Plain (NCP).Drip fertigation is considered to b...Excessive application of nitrogen (N) fertilizer is the main cause of N loss and poor use efficiency in winter wheat (Triticum aestivum L.) production in the North China Plain (NCP).Drip fertigation is considered to be an effective method for improving N use efficiency and reducing losses,while the performance of drip fertigation in winter wheat is limited by poor N scheduling.A two-year field experiment was conducted to evaluate the growth,development and yield of drip-fertigated winter wheat under different split urea (46%N,240 kg ha^(-1)) applications.The six treatments consisted of five fertigation N application scheduling programs and one slow-release fertilizer (SRF) application.The five N scheduling treatments were N0–100 (0%at sowing and 100%at jointing/booting),N25–75 (25%at sowing and 75%at jointing and booting),N50–50(50%at sowing and 50%at jointing/booting),N75–25 (75%at sowing and 25 at jointing/booting),and N100–0 (100%at sowing and 0%at jointing/booting).The SRF (43%N,240 kg ha^(-1)) was only used as fertilizer at sowing.Split N application significantly (P<0.05) affected wheat grain yield,yield components,aboveground biomass (ABM),water use efficiency(WUE) and nitrogen partial factor productivity (NPFP).The N50–50 and SRF treatments respectively had the highest yield(8.84 and 8.85 t ha^(-1)),ABM (20.67 and 20.83 t ha^(-1)),WUE (2.28 and 2.17 kg m^(-3)) and NPFP (36.82 and 36.88 kg kg^(-1)).This work provided substantial evidence that urea-N applied in equal splits between basal and topdressing doses compete economically with the highly expensive SRF for fertilization of winter wheat crops.Although the single-dose SRF could reduce labor costs involved with the traditional method of manual spreading,the drip fertigation system used in this study with the N50–50 treatment provides an option for farmers to maintain wheat production in the NCP.展开更多
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
Zn（Ⅱ） and Pb（Ⅱ） from Nigerian sphalerite and galena ores were bioleached by a mixed culture of acidophilic bacteria.The influences of pH and ferric ion on the bioleaching rates of sphalerite and galena were exam...Zn（Ⅱ） and Pb（Ⅱ） from Nigerian sphalerite and galena ores were bioleached by a mixed culture of acidophilic bacteria.The influences of pH and ferric ion on the bioleaching rates of sphalerite and galena were examined.The result shows that pH 2.1 and 2.7 are favourable for the leaching of Zn（Ⅱ） and Pb（Ⅱ） from sphalerite and galena,respectively.It was observed that the use of agarose-simulated media caused cells to excrete exopolymers containing ferric ions which enhanced oxidation.The oxidation equilibrium for sphalerite and galena took 3 and 4 d,respectively.About 38.3% sphalerite and 34.2% galena were leached within 1 d and approximately 92.0% Zn（Ⅱ） and 89.0% Pb（Ⅱ） were recovered in 5 d,respectively.The unleached residual products were examined by X-ray diffraction for sphalerite,revealing the presence of elemental sulphur（S）,zinc sulphate（ZnSO4） and few traces of calcium aluminate（Ca3Al2O6）.The XRD pattern also indicates the presence of elemental sulphur（S）,lead sulphate（PbSO4） and few traces of itoite [Pb（S,Ge）（O,OH）4] and cobalt lead silicate [Pb8Co（Si2O7）3] in the unleached galena ore.展开更多
Genome-wide association study(GWAS)is effective in identifying favorable alleles for traits of interest with high mapping resolution in crop species.In this study,we conducted GWAS to explore quantitative trait loci(Q...Genome-wide association study(GWAS)is effective in identifying favorable alleles for traits of interest with high mapping resolution in crop species.In this study,we conducted GWAS to explore quantitative trait loci(QTL)for eight fruit traits using 162 tomato accessions with diverse genetic backgrounds.The eight traits included fruit weight,fruit width,fruit height,fruit shape index,pericarp thickness,locule number,fruit firmness,and brix.Phenotypic variations of these traits in the tomato collection were evaluated with three replicates in field trials over three years.We filtered 34,550 confident SNPs from the 51K Axiom®tomato array based on<10%of missing data and>5%of minor allele frequency for association analysis.The 162 tomato accessions were divided into seven clusters and their membership coefficients were used to account for population structure along with a kinship matrix.To identify marker-trait associations(MTAs),four phenotypic data sets representing each of three years and combined were independently analyzed in the multilocus mixed model(MLMM).A total of 30 significant MTAs was detected over data sets for eight fruit traits at P<0.0005.The number of MTA per trait ranged from one(brix)to seven(fruit weight and fruit width).Two SNP markers on chromosomes 1 and 2 were significantly associated with multiple traits,suggesting pleiotropic effects of QTL.Furthermore,16 of 30 MTAs suggest potential novel QTL for eight fruit traits.These results facilitate genetic dissection of tomato fruit traits and provide a useful resource to develop molecular tools for improving fruit traits via marker-assisted selection and genomic selection in tomato breeding programs.展开更多
Field pea(Pisum sativum L.) is an important protein-rich pulse crop produced globally. Increasing the lipid content of Pisum seeds through conventional and contemporary molecular breeding tools may bring added value t...Field pea(Pisum sativum L.) is an important protein-rich pulse crop produced globally. Increasing the lipid content of Pisum seeds through conventional and contemporary molecular breeding tools may bring added value to the crop. However, knowledge about genetic diversity and lipid content in field pea is limited. An understanding of genetic diversity and population structure in diverse germplasm is important and a prerequisite for genetic dissection of complex characteristics and marker-trait associations. Fifty polymorphic microsatellite markers detecting a total of 207 alleles were used to obtain information on genetic diversity, population structure and marker-trait associations. Cluster analysis was performed using UPGMA to construct a dendrogram from a pairwise similarity matrix. Pea genotypes were divided into five major clusters. A model-based population structure analysis divided the pea accessions into four groups. Percentage lipid content in 35 diverse pea accessions was used to find potential associations with the SSR markers. Markers AD73, D21, and AA5 were significantly associated with lipid content using a mixed linear model(MLM) taking population structure(Q) and relative kinship(K) into account. The results of this preliminary study suggested that the population could be used for marker-trait association mapping studies.展开更多
Supercapacitors are favored by researchers because of their high power density,especially with the acceleration of people’s life rhythm.However,their energy density,especially from the point of view of the whole ener...Supercapacitors are favored by researchers because of their high power density,especially with the acceleration of people’s life rhythm.However,their energy density,especially from the point of view of the whole energy storage device,is far lower than that of commercial batteries.In this work,a kind of customizable full paper-based supercapacitor device with excellent self-healing ability is fabricated by simple and low-cost screen printing,electropolymerization and dip coating methods.The resultant separatorfree supercapacitor device exhibits both ultrahigh gravimetric and areal specific energy(power)densities of 39 Wh kg^(-1)(69 k W kg^(-1))and 692μWh cm^(-2)(236 m W cm^(-2)),achieving excellent supercapacitor performance.Notably,the addition of vitrimers endows the whole device with outstanding self-healing properties,which is helpful for enhancing the adaptability of the device to the environment.In addition,this kind of paper-based device also displays good photothermal and electromagnetic shielding performances.These striking features make paper matrix composites attractive in the fields of supercapacitors,medical photothermal treatment and electromagnetic shielding.展开更多
Three pumpkin species Cucurbita maxima,C.moschata,and C.pepo are commonly cultivated worldwide.To identify genome-wide SNPs in these cultivated pumpkin species,we collected 48 F1 cultivars consisting of 40 intraspecif...Three pumpkin species Cucurbita maxima,C.moschata,and C.pepo are commonly cultivated worldwide.To identify genome-wide SNPs in these cultivated pumpkin species,we collected 48 F1 cultivars consisting of 40 intraspecific hybrids(15 C.maxima,18 C.moschata,and 7 C.pepo)and 8 interspecific hybrids(C.maxima x C.moschata).Genotyping by sequencing identified a total of 37,869 confident SNPs in this collection.These SNPs were filtered to generate a subset of 400 SNPs based on polymorphism and genome distribution.Of the 400 SNPs,288 were used to genotype an additional 188 accessions(94 F1 cultivars,50 breeding lines,and 44 landraces)with a SNP array-based platform.Reliable polymorphisms were observed in 224 SNPs(78.0%)and were used to assess genetic variations between and within the four predefined populations in 223 cultivated pumpkin accessions.Both principal component analysis and UPGMA clustering found four major clusters representing three pumpkin species and interspecific hybrids.This genetic differentiation was supported by pairwise Fst and Nei’s genetic distance.The interspecific hybrids showed a higher level of genetic diversity relative to the other three populations.Of the 224 SNPs,five subsets of 192,96,48,24,and 12 markers were evaluated for variety identification.The 192,96,and 48 marker sets identified 204(91.5%),190(85.2%),and 141(63.2%)of the 223 accessions,respectively,while other subsets showed<25%of variety identification rates.These SNP markers provide a molecular tool with many applications for genetics and breeding in cultivated pumpkin.展开更多
The changes in total polyphenolics in elderberry (Sambucus nigra) following treatment with various doses of pulsed ultraviolet rays (UV) were investigated. Four pulsed UV durations (5, 10, 20, 30 seconds) at three ene...The changes in total polyphenolics in elderberry (Sambucus nigra) following treatment with various doses of pulsed ultraviolet rays (UV) were investigated. Four pulsed UV durations (5, 10, 20, 30 seconds) at three energy dosages (4500, 6000, 11,000 J/m2/pulse) were considered for the research. All treated elderberry fruits were incubated for 24 h at room temperature (25℃) following treatment to ensure enough response duration for enhanced development of polyphenols by the berries. The highest increase in total phenolics around 50% was found with 11,000 J/m2/pulse for a 10 seconds treatment while nearly 40% increase in total phenolics was found at an energy dosage of 11,000 J/m2/pulse after 5 seconds exposure. Even though most of the treatments indicated an increase in total polyphenols, some treatment expressed a decrease in phenolics content when compared to untreated fruits.展开更多
Street food trading solves major social and economic problems in developing countries through the provision of ready-made meals at relatively inexpensive prices and employment for teeming rural and urban populace alon...Street food trading solves major social and economic problems in developing countries through the provision of ready-made meals at relatively inexpensive prices and employment for teeming rural and urban populace along its value chain.However,due to informal nature of the enterprise,the activities of the practitioners are not regulated.This gives ample room for unwholesome practices.The results are the risks such activities pose to the health and safety of practitioners along the value chain.This review paper,a summary of literature reports on risk factors in street food trade in developing countries and recommended safety intervention,is written with the hope of providing global baseline for intervention to ensure safe food practices.Adoption of safety approaches that permeates the entire chain of street food business from good agricultural practices through hazard analysis critical control points strategy to good hygiene practices by farmers,vendors and consumers would significantly reduce risks in street food consumption.Above all,active collaboration of all stakeholders toward the strengthening and proper enforcement of public health policies to ensure safe practices and engender safer and healthier society is recommended.展开更多
文摘The engineering profession has responded to the issue of sustainable development in two main ways. It has responded through public policy statements that acknowledge the magnitude of the problem in addition to pledging to steer engineering towards a more sustainable future, and it has also responded more directly through technological innovation. In this paper, these two responses will be explored with respect to the debate on how to operationalize sustainability principles in practical terms. This paper also attempts to provide the rationale for a philosophy of engineering ethics grounded in the notion of sustainable development. It is hoped that this would lead to a revised “social contract” that would enable engineers to engage more actively in political, technical, economic and social discussions and processes.
基金supported by the National Research Foundation of Korea grant funded by the Korea government(Grant Nos.NRF-2020R1A2C1007778 and RS-2024-00454908)。
文摘This study explores the broad-spectrum application of OsRALF26,a small secreted peptide belonging to the rapid alkalinization factor(RALF)family in rice.We found that the rice genome carries numerous lineage-specific OsRALFs,suggesting that this evolutionary expansion could be the result of an arms race with pathogens.Among them,we focused on the Oryza-specific Os RALF26 and its closest homolog,OsRALF27,analyzing their effects across a range of plant species from monocots to dicots.The exogenous application of OsRALF26 significantly reduced bacterial populations in rice challenged with Xanthomonas oryzae pv.oryzae(Xoo)and in Arabidopsis and tomato challenged with Pseudomonas syringae pv.tomato DC3000(Pst DC3000),whereas Os RALF27 did not enhance resistance.
基金supported by the China Agriculture Research System of MOF and MARA (CARS-03-19)the National Natural Science Foundation of China (51879267)the Agricultural Science and Technology Innovation Program (ASTIP), Chinese Academy of Agricultural Sciences。
文摘Irrigation methods and nitrogen(N) fertilization modes have complicated impacts on wheat physiology, growth, and development, leading to the regulation of wheat grain yield and quality. However, the optimal water-N combination for drip-irrigated winter wheat remains unclear. A two-year field study was conducted to evaluate the influences of various N-fertigation and water regimes on wheat post-anthesis grain weight variation, yield, grain NPK content, and grain quality. The two irrigation quotas were I_(45)(irrigation when crop evapotranspiration reduced by effective rainfall(ETa-P) reaches 45 mm) and I_(30)(irrigation when ETa-P reaches 30 mm), while the six N application rates were N_(0–100)(100% at jointing/booting), N_(25–75)(25% at sowing and 75% at jointing/booting), N_(50–50)(50% at sowing and 50% at jointing/booting), N_(75–25)(75% at sowing and 25% at jointing/booting), N_(100–0)(100% at sowing), and SRF100(100% of slow-release fertilizer at sowing). The experimental findings showed that post-anthesis grain weight variation, grain yield, grain NPK content, and grain quality were all markedly influenced by the various irrigation schedules and N-fertilization modes. The N_(50–50)treatment was more beneficial for winter wheat post-anthesis grain weight variation than the N_(100–0)and N_(0–100)treatments under the two irrigation quotas and during the two seasons. The highest grain yields of 9.72 and9.94(t ha^(-1)) were obtained with the I_(45)N_(50–50)treatment in 2020–2021 and 2021–2022, respectively. The grain crudeprotein was higher in the I_(45)SRF100treatment during the two seasons. The I_(45)N_(100–0)combination significantly(P<0.05)enhanced the content of grain total starch by 7.30 and 8.23% compared with the I_(45)N_(0–100)and I_(30)N_(0–100)treatments,respectively, during the 2021–2021 season. The I_(45)N_(100–0)treatment significantly(P<0.05) enhanced the content ofgrain total starch concentration by 7.77, 7.62 and 7.88% compared with the I_(45)N_(0–100), I_(30)N_(0–100), and I_(30)N_(25–75)treatments,respectively, in the 2021–2022 season. The principal component analysis(PCA) indicated that the N_(50–50)splitN-fertigation mode could be the optimal choice for farmers during winter wheat production via drip irrigation.
基金supported by the fund of the National Natural Science Foundation of China(Nos.22378249,22078184,and 22171170)the China Postdoctoral Science Foundation(No.2019M653853XB)the Natural Science Advance Research Foundation of Shaanxi University of Science and Technology(No.2018QNBJ-03).
文摘The demand for flexible electric heating devices has increased due to technology advancement and improved living standards.These devices have various applications including personal thermal management,hyperthermia,defrosting,agricultural heating film,and oil-water separation.Joule heat,generated by electric currents,is commonly used in electrical appliances.To incorporate Joule heating into flexible electronics,new materials with excellent mechanical properties are necessary.Traditional polymers,used as reinforcements,limit the continuity of conductive networks in composites.Therefore,there is a need to develop flexible Joule thermal composite materials with enhanced mechanical strength and conductivity.Cellulose,a widely available renewable resource,is attracting attention for its excellent mechanical properties.It can be used as a dispersant and reinforcing agent for conductive fillers in cellulose-based composites,creating highly conductive networks.Various forms of cellulose,such as wood,nanocellulose,pulp fiber,bacterial cellulose,cellulose paper,textile clothing,and aramid fiber,have been utilized to achieve high-performance Joule thermal composites.Researchers have achieved excellent mechanical properties and developed efficient electric heating devices by designing cellulose-based composites with different structures.The scalable production methods enable large-scale application of cellulose-based devices,each with unique advantages in 1D,2D,and 3D structures.This review summarizes recent advancements in cellulose-based Joule thermal composites,providing insights into different structural devices,and discussing prospects and challenges in the field.
基金国家高技术研究发展计划(863计划)(2013AA102904)高等学校学科创新引智计划(111计划)资助项目(B12007)Iowa Department of Agriculture and Land Stewardship
文摘在玉米-大豆轮作系统中种植冬季覆盖作物黑麦有助于减小地下排水量和硝态氮(NO_3^--N)的流失量。该研究利用美国爱荷华州的试验数据校正和验证了DRAINMOD-N II模型在美国寒冷地区的适用性,并模拟长期(20 a)种植冬季覆盖作物黑麦对地下排水量和氮素运移的影响。结果表明,模型模拟地下排水量和NO_3^--N流失量时,Nash-Sutcliffe模型效率系数(Nash-Sutcliffe efficiency,NSE)>0.65、百分比偏差(percent bias,PBIAS)在±25%之间、均方根误差与标准差比值(ratio of root mean square error to standard deviation,RSR)≤0.7均在误差范围内;模拟地下排水中NO_3^--N浓度时,NSE>0.50、PBIAS在±15%之间、RSR≤0.5均在误差范围内,说明模型模拟的效果好。长期种植冬季覆盖作物黑麦可降低排水量8.1%(2.5 cm),减小NO_3^--N流失量16.6%(6 kg/hm^2),NO_3^--N流量加权平均浓度下降了8.6%(1 mg/L,以N计),增加蒸散值5.9%,模型模拟值与实测值拟合效果好,表明模型具有良好的水文和氮素运移模拟功能,可以模拟不同农田管理措施对地下水和氮素运移的长期影响,为优化农田管理措施提供参考。
基金financially supported by the Singapore Economic Development Board (EDB) through Minerals Metals and Materials Technology Centre (M3TC) (No.R261501013414)
文摘Presence of fine dust in air causes serious health hazard for mine operators resulting in such serious problems as coal workers’pneumoconiosis and silicosis.Major sources of dust appear of course along the mining face where the minerals are extracted.Proper control and management are required to ensure safe working environment in the mine.Here,we utilize the computational fluid dynamic(CFD)approach to evaluate various methods used for mitigating dust dispersion from the mining face and for ensuring safe level of dust concentration in the mine tunnel for safety of the operators.The methods used include:application of blowing and exhaust fans,application of brattice and combination of both.The results suggest that among the examined methods,implementation of appropriately located brattice to direct the flow from the main shaft to the mining face is the most effective method to direct dust particles away from the mining face.
文摘The feasibility of using two types of biochars to reduce steroid hormone pollution from poultry and swine manure application on agricultural land was evaluated. The sorption affinity and desorption resistance of softwood and hardwood biochars were also determined for two estrogen hormones, 17β-estradiol （E2） and its primary metabolite estrone （E1）. The softwood and hardwood biochars demonstrated high retention capacity for both estrogens. The effective distribution coefficient （Kedff） of soil-softwood-derived biochar （SBS450） was significantly higher than soil-hardwood-derived biochar （SBH750）, indicating the stronger sorption affinity of SBS450 for estrogens. To validate the laboratory results, a field lysimeter experiment was conducted to study the fate and transport of E2 and E1 in soil and leachate in the presence of 1% softwood-biochar （BS450） in topsoil and to compare it with soil without any amendments. The spatio-temporal distribution of both estrogens was monitored at four depths over a 46-day period. The lysimeters, in which the surface layer of soil was amended with biochar, retained significantly higher concentrations of both estrogen hormones. Although they leached through the soil and were detected in leachates, collected at 1.0 m depth, the concentrations were significantly lower in the leachate collected from biochar-amended lysimeters. The result confirmed the efficacy of biochar amendment as a remediation technique to alleviate the manure-borne hormonal pollution of groundwater.
基金funded by the earmarked fund for China Agriculture Research System(CARS-03-19)the National Natural Science Foundation of China(51879267 and 51709264)+1 种基金the Open Fund Projects of the Agricultural Environment Experimental Station of Minstry of Agriculture and Rural Affairs,China(FIRI2021040103)the Agricultural Science and Technology Innovation Program(ASTIP)of Chinese Academy of Agricultural Sciences。
文摘Excessive application of nitrogen (N) fertilizer is the main cause of N loss and poor use efficiency in winter wheat (Triticum aestivum L.) production in the North China Plain (NCP).Drip fertigation is considered to be an effective method for improving N use efficiency and reducing losses,while the performance of drip fertigation in winter wheat is limited by poor N scheduling.A two-year field experiment was conducted to evaluate the growth,development and yield of drip-fertigated winter wheat under different split urea (46%N,240 kg ha^(-1)) applications.The six treatments consisted of five fertigation N application scheduling programs and one slow-release fertilizer (SRF) application.The five N scheduling treatments were N0–100 (0%at sowing and 100%at jointing/booting),N25–75 (25%at sowing and 75%at jointing and booting),N50–50(50%at sowing and 50%at jointing/booting),N75–25 (75%at sowing and 25 at jointing/booting),and N100–0 (100%at sowing and 0%at jointing/booting).The SRF (43%N,240 kg ha^(-1)) was only used as fertilizer at sowing.Split N application significantly (P<0.05) affected wheat grain yield,yield components,aboveground biomass (ABM),water use efficiency(WUE) and nitrogen partial factor productivity (NPFP).The N50–50 and SRF treatments respectively had the highest yield(8.84 and 8.85 t ha^(-1)),ABM (20.67 and 20.83 t ha^(-1)),WUE (2.28 and 2.17 kg m^(-3)) and NPFP (36.82 and 36.88 kg kg^(-1)).This work provided substantial evidence that urea-N applied in equal splits between basal and topdressing doses compete economically with the highly expensive SRF for fertilization of winter wheat crops.Although the single-dose SRF could reduce labor costs involved with the traditional method of manual spreading,the drip fertigation system used in this study with the N50–50 treatment provides an option for farmers to maintain wheat production in the NCP.
基金supported by National Natural Science Foundation of China(Nos.31871861 and 31501548)The Apicultural Industry Technology System(NCYTI-43-KXJ17)The Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2015-IAR)。
文摘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.
文摘Zn（Ⅱ） and Pb（Ⅱ） from Nigerian sphalerite and galena ores were bioleached by a mixed culture of acidophilic bacteria.The influences of pH and ferric ion on the bioleaching rates of sphalerite and galena were examined.The result shows that pH 2.1 and 2.7 are favourable for the leaching of Zn（Ⅱ） and Pb（Ⅱ） from sphalerite and galena,respectively.It was observed that the use of agarose-simulated media caused cells to excrete exopolymers containing ferric ions which enhanced oxidation.The oxidation equilibrium for sphalerite and galena took 3 and 4 d,respectively.About 38.3% sphalerite and 34.2% galena were leached within 1 d and approximately 92.0% Zn（Ⅱ） and 89.0% Pb（Ⅱ） were recovered in 5 d,respectively.The unleached residual products were examined by X-ray diffraction for sphalerite,revealing the presence of elemental sulphur（S）,zinc sulphate（ZnSO4） and few traces of calcium aluminate（Ca3Al2O6）.The XRD pattern also indicates the presence of elemental sulphur（S）,lead sulphate（PbSO4） and few traces of itoite [Pb（S,Ge）（O,OH）4] and cobalt lead silicate [Pb8Co（Si2O7）3] in the unleached galena ore.
基金This work was carried out with the support of Cooperative Research Program for Agriculture Science and Technology Development(Project No.PJ0158982021)the Next-Generation BioGreen21 Program(Project No.PJ0131142020)Rural Development Administration,Republic of Korea.
文摘Genome-wide association study(GWAS)is effective in identifying favorable alleles for traits of interest with high mapping resolution in crop species.In this study,we conducted GWAS to explore quantitative trait loci(QTL)for eight fruit traits using 162 tomato accessions with diverse genetic backgrounds.The eight traits included fruit weight,fruit width,fruit height,fruit shape index,pericarp thickness,locule number,fruit firmness,and brix.Phenotypic variations of these traits in the tomato collection were evaluated with three replicates in field trials over three years.We filtered 34,550 confident SNPs from the 51K Axiom®tomato array based on<10%of missing data and>5%of minor allele frequency for association analysis.The 162 tomato accessions were divided into seven clusters and their membership coefficients were used to account for population structure along with a kinship matrix.To identify marker-trait associations(MTAs),four phenotypic data sets representing each of three years and combined were independently analyzed in the multilocus mixed model(MLMM).A total of 30 significant MTAs was detected over data sets for eight fruit traits at P<0.0005.The number of MTA per trait ranged from one(brix)to seven(fruit weight and fruit width).Two SNP markers on chromosomes 1 and 2 were significantly associated with multiple traits,suggesting pleiotropic effects of QTL.Furthermore,16 of 30 MTAs suggest potential novel QTL for eight fruit traits.These results facilitate genetic dissection of tomato fruit traits and provide a useful resource to develop molecular tools for improving fruit traits via marker-assisted selection and genomic selection in tomato breeding programs.
基金supported by the Natural Sciences and Engineering Research Council of Canada Collaborative Research and Development and Lefsrud Seeds (CRDRJ385395-09)
文摘Field pea(Pisum sativum L.) is an important protein-rich pulse crop produced globally. Increasing the lipid content of Pisum seeds through conventional and contemporary molecular breeding tools may bring added value to the crop. However, knowledge about genetic diversity and lipid content in field pea is limited. An understanding of genetic diversity and population structure in diverse germplasm is important and a prerequisite for genetic dissection of complex characteristics and marker-trait associations. Fifty polymorphic microsatellite markers detecting a total of 207 alleles were used to obtain information on genetic diversity, population structure and marker-trait associations. Cluster analysis was performed using UPGMA to construct a dendrogram from a pairwise similarity matrix. Pea genotypes were divided into five major clusters. A model-based population structure analysis divided the pea accessions into four groups. Percentage lipid content in 35 diverse pea accessions was used to find potential associations with the SSR markers. Markers AD73, D21, and AA5 were significantly associated with lipid content using a mixed linear model(MLM) taking population structure(Q) and relative kinship(K) into account. The results of this preliminary study suggested that the population could be used for marker-trait association mapping studies.
基金financially supported by the National Natural Science Foundation of China(No.22078184)the China Postdoctoral Science Foundation(No.2019M653853XB)+6 种基金the Natural Science Foundation of Shaanxi Province(No.2020JQ-729)the Key Projects of Collaborative Innovation Center of Shaanxi Provincial Department of Educationthe Opening Project of Guangxi Key Laboratory of Clean Pulp&Papermaking and Pollution Control(No.2019KF21)the Natural Science Advance Research Foundation of Shaanxi University of Science and Technology(No.2018QNBJ-03)the National Demonstration Center for Experimental Light Chemistry Engineering Education(No.2018QGSJ02-13)the Jiangxi Qingyue Technology Co.,Ltd(No.210200122)the Biomass Chemistry and Materials Academician Workstation Project in SUST(No.134090002)。
文摘Supercapacitors are favored by researchers because of their high power density,especially with the acceleration of people’s life rhythm.However,their energy density,especially from the point of view of the whole energy storage device,is far lower than that of commercial batteries.In this work,a kind of customizable full paper-based supercapacitor device with excellent self-healing ability is fabricated by simple and low-cost screen printing,electropolymerization and dip coating methods.The resultant separatorfree supercapacitor device exhibits both ultrahigh gravimetric and areal specific energy(power)densities of 39 Wh kg^(-1)(69 k W kg^(-1))and 692μWh cm^(-2)(236 m W cm^(-2)),achieving excellent supercapacitor performance.Notably,the addition of vitrimers endows the whole device with outstanding self-healing properties,which is helpful for enhancing the adaptability of the device to the environment.In addition,this kind of paper-based device also displays good photothermal and electromagnetic shielding performances.These striking features make paper matrix composites attractive in the fields of supercapacitors,medical photothermal treatment and electromagnetic shielding.
基金supported by the Korea Institute of Planning and Evaluation for Technology in Food,Agriculture,Forestry and Fisheries(IPET)through the Agri-Bioindustry Technology Development Program funded by the Ministry of Agriculture,Food and Rural Affairs(MAFRA)(No.317011-04-3-HD030)to S.S.
文摘Three pumpkin species Cucurbita maxima,C.moschata,and C.pepo are commonly cultivated worldwide.To identify genome-wide SNPs in these cultivated pumpkin species,we collected 48 F1 cultivars consisting of 40 intraspecific hybrids(15 C.maxima,18 C.moschata,and 7 C.pepo)and 8 interspecific hybrids(C.maxima x C.moschata).Genotyping by sequencing identified a total of 37,869 confident SNPs in this collection.These SNPs were filtered to generate a subset of 400 SNPs based on polymorphism and genome distribution.Of the 400 SNPs,288 were used to genotype an additional 188 accessions(94 F1 cultivars,50 breeding lines,and 44 landraces)with a SNP array-based platform.Reliable polymorphisms were observed in 224 SNPs(78.0%)and were used to assess genetic variations between and within the four predefined populations in 223 cultivated pumpkin accessions.Both principal component analysis and UPGMA clustering found four major clusters representing three pumpkin species and interspecific hybrids.This genetic differentiation was supported by pairwise Fst and Nei’s genetic distance.The interspecific hybrids showed a higher level of genetic diversity relative to the other three populations.Of the 224 SNPs,five subsets of 192,96,48,24,and 12 markers were evaluated for variety identification.The 192,96,and 48 marker sets identified 204(91.5%),190(85.2%),and 141(63.2%)of the 223 accessions,respectively,while other subsets showed<25%of variety identification rates.These SNP markers provide a molecular tool with many applications for genetics and breeding in cultivated pumpkin.
文摘The changes in total polyphenolics in elderberry (Sambucus nigra) following treatment with various doses of pulsed ultraviolet rays (UV) were investigated. Four pulsed UV durations (5, 10, 20, 30 seconds) at three energy dosages (4500, 6000, 11,000 J/m2/pulse) were considered for the research. All treated elderberry fruits were incubated for 24 h at room temperature (25℃) following treatment to ensure enough response duration for enhanced development of polyphenols by the berries. The highest increase in total phenolics around 50% was found with 11,000 J/m2/pulse for a 10 seconds treatment while nearly 40% increase in total phenolics was found at an energy dosage of 11,000 J/m2/pulse after 5 seconds exposure. Even though most of the treatments indicated an increase in total polyphenols, some treatment expressed a decrease in phenolics content when compared to untreated fruits.
文摘Street food trading solves major social and economic problems in developing countries through the provision of ready-made meals at relatively inexpensive prices and employment for teeming rural and urban populace along its value chain.However,due to informal nature of the enterprise,the activities of the practitioners are not regulated.This gives ample room for unwholesome practices.The results are the risks such activities pose to the health and safety of practitioners along the value chain.This review paper,a summary of literature reports on risk factors in street food trade in developing countries and recommended safety intervention,is written with the hope of providing global baseline for intervention to ensure safe food practices.Adoption of safety approaches that permeates the entire chain of street food business from good agricultural practices through hazard analysis critical control points strategy to good hygiene practices by farmers,vendors and consumers would significantly reduce risks in street food consumption.Above all,active collaboration of all stakeholders toward the strengthening and proper enforcement of public health policies to ensure safe practices and engender safer and healthier society is recommended.
