Unbalanced fertilizer application with high intensity nitrogen(N)and insufficient potassium(K)results in declining soil fertility.Balanced fertilization represents an effective approach to reduce fertilizer usage whil...Unbalanced fertilizer application with high intensity nitrogen(N)and insufficient potassium(K)results in declining soil fertility.Balanced fertilization represents an effective approach to reduce fertilizer usage while enhancing maize yield and efficiency.This study examined two N levels(180 and 225 kg N ha^(-1),abbreviated N12 and N15)and four K treatments(0,75,150,and 75+75 kg K_(2)O ha^(-1),abbreviated K0,K5,K10,and K5+5)to investigate the effects of combined N and K application on biomass,nutrient accumulation,and remobilization characteristics in waxy maize.Results indicated that grain yield increased with higher K application at constant N levels,demonstrating an average increase of 1,254.8 kg ha^(-1)(2020)and 727.3 kg ha^(-1)(2021)compared with K0.Under identical N and K applications,K5+5 enhanced grain yield through increased kernel weight.The K5+5 treatment showed no significant difference in biomass and nutrient accumulation between N12 and N15.Compared to K10,K5+5 enhanced both the average remobilization amount(RBA)of biomass and increased RBA of N,phosphorus(P)and K.Additionally,the average remobilization efficiency(RBE)of biomass,N,P,and K in K5+5 increased by 3.3,4.6,10.6,and 4.2%,respectively.Moreover,topdressing K improved the apparent contribution to grain(AC)of biomass,N,P and K,facilitating greater nutrient transfer to grains and significantly increasing nutrient harvest index.Based on yield and fertilizer use efficiency,this study recommends optimized K application(basal and topdressing 75 kg ha^(-1))and moderate reduction in N application(from 225 to 180 kg ha^(-1))for spring-sown waxy maize production in southern China.展开更多
Modified ethylene-vinyl acetate copolymer(EVAM)and amino-functionalized nano-silica(NSiO_(2))par-ticles were employed as the base materials for the synthesis of the nanocomposite pour point depressant designated as EV...Modified ethylene-vinyl acetate copolymer(EVAM)and amino-functionalized nano-silica(NSiO_(2))par-ticles were employed as the base materials for the synthesis of the nanocomposite pour point depressant designated as EVAM-g-NSiO_(2).This synthesis involved a chemical grafting process within a solution system,followed by a structural characterization.Moreover,combining macro-rheological performance with microscopic structure observation,the influence of the nanocomposite pour point depressant on the rheological properties of the model waxy oil system was investigated.The results indicate that when the mass ratio of NSiO_(2) to EVAM is 1:100,the prepared EVAM-g-NSiO_(2) nanocomposite pour point depressant exhibits excellent pour point reduction and viscosity reduction properties.Moreover,the nanocomposite pour point depressant obtained through a chemical grafting reaction demonstrates structural stability(the bonding between the polymer and nanoparticles is stable).The pour points of model waxy oils doped with 500 mg/kg ethylene-vinyl acetate copolymer(EVA),EVAM,and EVAM/SiO_(2) were reduced from 34℃ to 23,20,and 21℃,respectively.After adding the same dosage of EVAM-g-NSiO_(2) nanocomposite pour point depressant,the pour point of the model wax oil decreased to 12℃ and the viscosity at 32℃ decreased from 2399 to 2396.9 mPa·s,achieving an impressive viscosity reduction rate of 99.9%.Its performance surpassed that of EVA,EVAM,and EVAM/SiO_(2).The EVAM-g-NSiO_(2) dispersed in the oil phase acts as the crystallization nucleus for wax crystals,resulting in a dense structure of wax crystals.The compact wax crystal blocks are difficult to overlap with each other,pre-venting the formation of a three-dimensional network structure,thereby improving the low-temperature flowability of the model waxy oil.展开更多
One-third of the global population is affected by micronutrient deficiency, particularly folate. Although folate synthesis has been relatively well characterized, few folate-related genes in maize have been cloned, an...One-third of the global population is affected by micronutrient deficiency, particularly folate. Although folate synthesis has been relatively well characterized, few folate-related genes in maize have been cloned, and the molecular mechanism regulating folate synthesis in maize remains unclear. In this study,transcriptome and proteome analyses of three waxy maize inbred lines with high, medium, and low folate contents were performed to identify key genes controlling folate biosynthesis. Pairwise comparisons revealed 21 differentially expressed genes and 20 differentially expressed proteins potentially associated with folate biosynthesis in the three lines. Six key folate-associated genes, Zm Mocos2, Zm GGH,Zm ADCL2, Zm CBR1, Zm SHMT, and Zm Pur H, were identified. These genes encode enzymes that potentially function in folate biosynthesis. Functional validation of one of these genes, Zm ADCL2, using an EMS mutant(Mut9264) showed that a 4-base insertion in an exon increased the folate content of fresh maize kernels 1.37-fold that of the wild type. Zm ADCL2 was considered a potential target for generating maize lines with higher folate content. KEGG enrichment analysis of differentially expressed genes and proteins showed that several pathways in addition to folate biosynthesis were likely indirectly involved in folate metabolism and content(e.g., glycine, serine, and threonine metabolism;purine metabolism;cysteine and methionine metabolism;alanine, aspartate and glutamate metabolism;glutathione metabolism;and pyruvate metabolism. The transcriptome and proteomic data generated in this study will help to clarify the mechanisms underlying folate accumulation and aid breeding efforts to biofortify maize with folate.展开更多
本研究测定了100份糜子种质资源的直链淀粉和支链淀粉含量,采用分子标记对胚乳直链淀粉合成调控基因Waxy进行基因分型,并选取不同直链淀粉含量代表种质资源进行基因测序和差异位点分析。结果表明,100份糜子种质资源直链淀粉含量变化幅度...本研究测定了100份糜子种质资源的直链淀粉和支链淀粉含量,采用分子标记对胚乳直链淀粉合成调控基因Waxy进行基因分型,并选取不同直链淀粉含量代表种质资源进行基因测序和差异位点分析。结果表明,100份糜子种质资源直链淀粉含量变化幅度为0~22.78%,平均6.07%,直链淀粉含量低于3.7%的糯性材料占36%,完全糯性材料占24%;支链淀粉含量变化幅度为4.55%~56.73%,平均15.30%。分子标记M5/R11扩增产物能有效区分S_(0)、S_(-15)和S_(0)S_(-15)基因型;标记int5Lf/R3和M12/R12的PCR产物利用内切酶ACC I和Eco N I剪切,可鉴别出L_(C)、L_(Y)、L_(F)基因型。100份糜子种质共发现9种基因型,其中S_(0)/L_(c)数量最多,占33%,S_(-15)/L_(F)占25%,杂合型S_(0)S_(-15)/L_(F)、S_(0)S_(-15)/L_(C)、S_(0)S_(-15)/L_(Y)L_(F)各占2%。通过Waxy基因序列比对,在地方品种甘谷黑蝉背、黑糜子、庆阳饿死牛,育成品种晋黍9号、赤糜2号等种质资源中发现了大量新的SNPs位点,可用于基因功能和糜子育种材料创制研究。本研究结果为糜子分子育种工作及品质改良提供了理论依据。展开更多
A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax depositi...A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax deposition in crude oil pipelines.Aiming at the shortcomings of the ENN prediction model,which easily falls into the local minimum value and weak generalization ability in the implementation process,an optimized ENN prediction model based on the IRSA is proposed.The validity of the new model was confirmed by the accurate prediction of two sets of experimental data on wax deposition in crude oil pipelines.The two groups of crude oil wax deposition rate case prediction results showed that the average absolute percentage errors of IRSA-ENN prediction models is 0.5476% and 0.7831%,respectively.Additionally,it shows a higher prediction accuracy compared to the ENN prediction model.In fact,the new model established by using the IRSA to optimize ENN can optimize the initial weights and thresholds in the prediction process,which can overcome the shortcomings of the ENN prediction model,such as weak generalization ability and tendency to fall into the local minimum value,so that it has the advantages of strong implementation and high prediction accuracy.展开更多
With the advancement of oilfield extraction technology,since oil-water emulsions in waxy crude oil are prone to be deposited on the pipe wall,increasing the difficulty of crude oil extraction.In this paper,the mesosco...With the advancement of oilfield extraction technology,since oil-water emulsions in waxy crude oil are prone to be deposited on the pipe wall,increasing the difficulty of crude oil extraction.In this paper,the mesoscopic dissipative particle dynamics method is used to study themechanism of the crystallization and deposition adsorbed on thewall.The results show that in the absence of water molecules,the paraffin molecules near the substrate are deposited on themetallic surface with a horizontalmorphology,while the paraffin molecules close to the fluid side are arranged in a vertical column morphology.In the emulsified system,more water molecules will be absorbed on the metallic substrate than paraffin molecules,which obstructed the direct interaction between paraffin molecules and solid surface.Therefore,the addition of watermolecules hinders the crystallization of wax near the substrate.Perversely,on the fluid side,water molecules promote the formation of paraffin crystallization.The research in this paper reveals the crystallization mechanism of paraffin wax in oil-water emulsions in the pipeline from the microscopic scale,which provides theoretical support for improving the recovery of wax-containing crude oil and enhancing the transport efficiency.展开更多
基金the financial support of the Jiangsu Agricultural Industry Technology System of China(JATS[2022]497)the Jiangsu Agriculture Science and Technology Innovation Fund,China(CX[23]3117)+2 种基金the Key Research&Development Program of Jiangsu Province,China(BE2021317)the National Natural Science Foundation of China(32101828)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China(PAPD)。
文摘Unbalanced fertilizer application with high intensity nitrogen(N)and insufficient potassium(K)results in declining soil fertility.Balanced fertilization represents an effective approach to reduce fertilizer usage while enhancing maize yield and efficiency.This study examined two N levels(180 and 225 kg N ha^(-1),abbreviated N12 and N15)and four K treatments(0,75,150,and 75+75 kg K_(2)O ha^(-1),abbreviated K0,K5,K10,and K5+5)to investigate the effects of combined N and K application on biomass,nutrient accumulation,and remobilization characteristics in waxy maize.Results indicated that grain yield increased with higher K application at constant N levels,demonstrating an average increase of 1,254.8 kg ha^(-1)(2020)and 727.3 kg ha^(-1)(2021)compared with K0.Under identical N and K applications,K5+5 enhanced grain yield through increased kernel weight.The K5+5 treatment showed no significant difference in biomass and nutrient accumulation between N12 and N15.Compared to K10,K5+5 enhanced both the average remobilization amount(RBA)of biomass and increased RBA of N,phosphorus(P)and K.Additionally,the average remobilization efficiency(RBE)of biomass,N,P,and K in K5+5 increased by 3.3,4.6,10.6,and 4.2%,respectively.Moreover,topdressing K improved the apparent contribution to grain(AC)of biomass,N,P and K,facilitating greater nutrient transfer to grains and significantly increasing nutrient harvest index.Based on yield and fertilizer use efficiency,this study recommends optimized K application(basal and topdressing 75 kg ha^(-1))and moderate reduction in N application(from 225 to 180 kg ha^(-1))for spring-sown waxy maize production in southern China.
基金supported by the National Natural Science Foundation of China(No.52076036)supported by the National Natural Science Foundation of China(No.52174020).
文摘Modified ethylene-vinyl acetate copolymer(EVAM)and amino-functionalized nano-silica(NSiO_(2))par-ticles were employed as the base materials for the synthesis of the nanocomposite pour point depressant designated as EVAM-g-NSiO_(2).This synthesis involved a chemical grafting process within a solution system,followed by a structural characterization.Moreover,combining macro-rheological performance with microscopic structure observation,the influence of the nanocomposite pour point depressant on the rheological properties of the model waxy oil system was investigated.The results indicate that when the mass ratio of NSiO_(2) to EVAM is 1:100,the prepared EVAM-g-NSiO_(2) nanocomposite pour point depressant exhibits excellent pour point reduction and viscosity reduction properties.Moreover,the nanocomposite pour point depressant obtained through a chemical grafting reaction demonstrates structural stability(the bonding between the polymer and nanoparticles is stable).The pour points of model waxy oils doped with 500 mg/kg ethylene-vinyl acetate copolymer(EVA),EVAM,and EVAM/SiO_(2) were reduced from 34℃ to 23,20,and 21℃,respectively.After adding the same dosage of EVAM-g-NSiO_(2) nanocomposite pour point depressant,the pour point of the model wax oil decreased to 12℃ and the viscosity at 32℃ decreased from 2399 to 2396.9 mPa·s,achieving an impressive viscosity reduction rate of 99.9%.Its performance surpassed that of EVA,EVAM,and EVAM/SiO_(2).The EVAM-g-NSiO_(2) dispersed in the oil phase acts as the crystallization nucleus for wax crystals,resulting in a dense structure of wax crystals.The compact wax crystal blocks are difficult to overlap with each other,pre-venting the formation of a three-dimensional network structure,thereby improving the low-temperature flowability of the model waxy oil.
基金supported by Youth Scientific Research Foundation of Beijing Academy of Agriculture and Forestry Sciences (QNJJ202208)the Collaborative Innovation Center of Beijing Academy of Agriculture and Forestry Sciences (KJCX20240408)+1 种基金Major Scientific and Technological Achievements Cultivation Project of Beijing Academy of Agriculture and Forestry SciencesNational Natural Science Foundation of China (32201815)。
文摘One-third of the global population is affected by micronutrient deficiency, particularly folate. Although folate synthesis has been relatively well characterized, few folate-related genes in maize have been cloned, and the molecular mechanism regulating folate synthesis in maize remains unclear. In this study,transcriptome and proteome analyses of three waxy maize inbred lines with high, medium, and low folate contents were performed to identify key genes controlling folate biosynthesis. Pairwise comparisons revealed 21 differentially expressed genes and 20 differentially expressed proteins potentially associated with folate biosynthesis in the three lines. Six key folate-associated genes, Zm Mocos2, Zm GGH,Zm ADCL2, Zm CBR1, Zm SHMT, and Zm Pur H, were identified. These genes encode enzymes that potentially function in folate biosynthesis. Functional validation of one of these genes, Zm ADCL2, using an EMS mutant(Mut9264) showed that a 4-base insertion in an exon increased the folate content of fresh maize kernels 1.37-fold that of the wild type. Zm ADCL2 was considered a potential target for generating maize lines with higher folate content. KEGG enrichment analysis of differentially expressed genes and proteins showed that several pathways in addition to folate biosynthesis were likely indirectly involved in folate metabolism and content(e.g., glycine, serine, and threonine metabolism;purine metabolism;cysteine and methionine metabolism;alanine, aspartate and glutamate metabolism;glutathione metabolism;and pyruvate metabolism. The transcriptome and proteomic data generated in this study will help to clarify the mechanisms underlying folate accumulation and aid breeding efforts to biofortify maize with folate.
文摘本研究测定了100份糜子种质资源的直链淀粉和支链淀粉含量,采用分子标记对胚乳直链淀粉合成调控基因Waxy进行基因分型,并选取不同直链淀粉含量代表种质资源进行基因测序和差异位点分析。结果表明,100份糜子种质资源直链淀粉含量变化幅度为0~22.78%,平均6.07%,直链淀粉含量低于3.7%的糯性材料占36%,完全糯性材料占24%;支链淀粉含量变化幅度为4.55%~56.73%,平均15.30%。分子标记M5/R11扩增产物能有效区分S_(0)、S_(-15)和S_(0)S_(-15)基因型;标记int5Lf/R3和M12/R12的PCR产物利用内切酶ACC I和Eco N I剪切,可鉴别出L_(C)、L_(Y)、L_(F)基因型。100份糜子种质共发现9种基因型,其中S_(0)/L_(c)数量最多,占33%,S_(-15)/L_(F)占25%,杂合型S_(0)S_(-15)/L_(F)、S_(0)S_(-15)/L_(C)、S_(0)S_(-15)/L_(Y)L_(F)各占2%。通过Waxy基因序列比对,在地方品种甘谷黑蝉背、黑糜子、庆阳饿死牛,育成品种晋黍9号、赤糜2号等种质资源中发现了大量新的SNPs位点,可用于基因功能和糜子育种材料创制研究。本研究结果为糜子分子育种工作及品质改良提供了理论依据。
文摘A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax deposition in crude oil pipelines.Aiming at the shortcomings of the ENN prediction model,which easily falls into the local minimum value and weak generalization ability in the implementation process,an optimized ENN prediction model based on the IRSA is proposed.The validity of the new model was confirmed by the accurate prediction of two sets of experimental data on wax deposition in crude oil pipelines.The two groups of crude oil wax deposition rate case prediction results showed that the average absolute percentage errors of IRSA-ENN prediction models is 0.5476% and 0.7831%,respectively.Additionally,it shows a higher prediction accuracy compared to the ENN prediction model.In fact,the new model established by using the IRSA to optimize ENN can optimize the initial weights and thresholds in the prediction process,which can overcome the shortcomings of the ENN prediction model,such as weak generalization ability and tendency to fall into the local minimum value,so that it has the advantages of strong implementation and high prediction accuracy.
基金sponsored by Natural Science Foundation of Xinjiang Uygur Autonomous Region,Grant No.2023D01C197Performance Incentive Guidance Project of Chongqing Scientific Research Institutions(cstc2022jxjl20016).
文摘With the advancement of oilfield extraction technology,since oil-water emulsions in waxy crude oil are prone to be deposited on the pipe wall,increasing the difficulty of crude oil extraction.In this paper,the mesoscopic dissipative particle dynamics method is used to study themechanism of the crystallization and deposition adsorbed on thewall.The results show that in the absence of water molecules,the paraffin molecules near the substrate are deposited on themetallic surface with a horizontalmorphology,while the paraffin molecules close to the fluid side are arranged in a vertical column morphology.In the emulsified system,more water molecules will be absorbed on the metallic substrate than paraffin molecules,which obstructed the direct interaction between paraffin molecules and solid surface.Therefore,the addition of watermolecules hinders the crystallization of wax near the substrate.Perversely,on the fluid side,water molecules promote the formation of paraffin crystallization.The research in this paper reveals the crystallization mechanism of paraffin wax in oil-water emulsions in the pipeline from the microscopic scale,which provides theoretical support for improving the recovery of wax-containing crude oil and enhancing the transport efficiency.
