Online fault detection is one of the key technologies to improve the performance of cloud systems. The current data of cloud systems is to be monitored, collected and used to reflect their state. Its use can potential...Online fault detection is one of the key technologies to improve the performance of cloud systems. The current data of cloud systems is to be monitored, collected and used to reflect their state. Its use can potentially help cloud managers take some timely measures before fault occurrence in clouds. Because of the complex structure and dynamic change characteristics of the clouds, existing fault detection methods suffer from the problems of low efficiency and low accuracy. In order to solve them, this work proposes an online detection model based on asystematic parameter-search method called SVM-Grid, whose construction is based on a support vector machine(SVM). SVM-Grid is used to optimize parameters in SVM. Proper attributes of a cloud system's running data are selected by using Pearson correlation and principal component analysis for the model. Strategies of predicting cloud faults and updating fault sample databases are proposed to optimize the model and improve its performance.In comparison with some representative existing methods, the proposed model can achieve more efficient and accurate fault detection for cloud systems.展开更多
Various biotic and abiotic stresses threaten the cultivation of future agricultural crops.Among these stresses,heat stress is a major abiotic stress that substantially reduces agricultural productivity.Many strategies...Various biotic and abiotic stresses threaten the cultivation of future agricultural crops.Among these stresses,heat stress is a major abiotic stress that substantially reduces agricultural productivity.Many strategies to enhance heat stress tolerance of crops have been developed,among which is grafting.Here,we show that Momordica-grafted cucumber scions have intrinsically enhanced chlorophyll content,leaf area,and net photosynthetic rate under heat stress compared to plants grafted onto cucumber rootstock.To investigate the mechanisms by which Momordica rootstock enhanced cucumber scions heat stress tolerance,comparative proteomic analysis of cucumber leaves in response to rootstock-grafting and/or heat stress was conducted.Seventy-seven differentially accumulated proteins involved in diverse biological processes were identified by two-dimensional electrophoresis(2-DE)in conjunction with matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry(MALDI-TOF/TOF MS).The following four main categories of proteins were involved:photosynthesis(42.8%),energy and metabolism(18.2%),defense response(14.3%),and protein and nucleic acid biosynthesis(11.7%).Proteomic analysis revealed that scions grafted onto Momordica rootstocks upregulated more proteins involved in photosynthesis compared to scions grafted onto cucumber rootstocks under heat stress and indicated enhanced photosynthetic capacity when seedlings were exposed to heat stress.Furthermore,the expression of photosynthesis-related genes in plants grafted onto Momordica rootstocks significantly increased in response to heat stress.In addition,increased high-temperature tolerance of plants grafted onto Momordica rootstock was associated with the accumulation of ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)and oxygen-evolving enhancer protein 1(OEE1).Taken together,the data indicated that Momordica rootstock might alleviate growth inhibition caused by heat stress by improving photosynthesis,providing valuable insight into enhancing heat stress tolerance in the global warming epoch.展开更多
In plants and algae,PGR5-dependent cyclic electron flow(CEF)is an important regulator of acclimation to fluctuating environments,but how PGR5 participates in CEF is unclear.In this work,we analyzed two PGR5s in cucumb...In plants and algae,PGR5-dependent cyclic electron flow(CEF)is an important regulator of acclimation to fluctuating environments,but how PGR5 participates in CEF is unclear.In this work,we analyzed two PGR5s in cucumber(Cucumis sativus L.)under different conditions and found that CsPGR5a played the dominant role in PGR5-dependent CEF.The results of yeast two-hybrid,biomolecular fluorescence complementation(BiFC),blue native PAGE,and coimmunoprecipitation(CoIP)assays showed that PGR5a interacted with PetC,Lhcb3,and PsaH.Furthermore,the intensity of the interactions was dynamic during state transitions,and the abundance of PGR5 attached to cyt b_(6)f decreased during the transition from state 1 to state 2,which revealed that the function of PGR5a is related to the state transition.We proposed that PGR5 is a small mobile protein that functions when attached to protein complexes.展开更多
Putrescine(Put),melatonin(MT),proline(Pro),and potassium fulvic acid(MFA)are widely used as plant growth regulators to enhance stress tolerance.However,the roles of their mixtures in response to stress are largely unk...Putrescine(Put),melatonin(MT),proline(Pro),and potassium fulvic acid(MFA)are widely used as plant growth regulators to enhance stress tolerance.However,the roles of their mixtures in response to stress are largely unknown.Here,we mixed Put with MT,Pro,and MFA(hereafter referred to as Put mixture)with different concentrations and foliar sprayed at different growth stages(seedling,flowering,and fruiting stage)of cucumber(Cucumis sativus L.)to investigate their roles on plant growth,fruit yield,and quality under high temperature stress.The foliar application of the Put mixture promoted cucumber growth,increased chlorophyll and Pro contents and net photosynthesis rate,and reduced the values of relative electrolyte leakage,H_(2)O_(2)and malondialdehyde contents of cucumber leaves,indicating that treatment with Put mixture reduced the oxidative stress caused by high temperature.Furthermore,Put mixture-treated cucumber plants had lower fruit deformity rate and higher fruit yield compared with control.The contents of vitamin C and soluble solids of cucumber fruit significantly increased and the contents of tannin and organic acid decreased.The most profound effects were found in the plants treated with 8 mmol L^(−1)Put,50μmol L^(−1)MT,1.5 mmol L^(−1)Pro and 0.3 g L^(−1)MFA every 7 d,three times at the seedling stage,indicating that cucumber seedlings treated with the mixture of Put,MT,Pro,and MFA significantly alleviated the negative effects of high temperature stress.展开更多
Plants,as sessile in nature,are constantly confronted with diverse biotic and abiotic stresses throughout their life cycle in the changing environment.As a result,plants evolved root-shoot communications to optimize p...Plants,as sessile in nature,are constantly confronted with diverse biotic and abiotic stresses throughout their life cycle in the changing environment.As a result,plants evolved root-shoot communications to optimize plant growth and development,and regulate responses to environmental stresses.Here,we examined the roles of root-sourced cytokinin(CTK)response to heat stress in grafted cucumber seedlings.Cucumber plants grafted onto cucumber roots and bitter gourd(Momordica charantia)roots were exposed to heat to examine their heat tolerance by assessing the levels of photosynthetic capacity,CTK contents,chlorophyll-a/b-binding protein(Lhcb2),ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)and its activating enzyme(RCA)content,and the enzyme activity of Rubisco.Bitter gourd rootstock enhanced cucumber scions heat stress tolerance.This enhancement was positively correlated with a higher content of CTK in both leaf and root parts,chlorophyll contents,and Rubisco abundance and activity.In addition,the higher level of CTK and Rubisco content in bitter gourd grafted plants shoots than in cucumber self-gafted plants shoots were attributed to an increase in CTK transport from roots in grafted plants under hightemperature conditions.These results indicated that CTK transfer from bitter gourd rootstock to scion and triggered the accumulation of Rubisco in leaf,thus improving the heat resistance of bitter gourd-grafted plants.展开更多
Transglutaminases(TGases),which are widespread cross-linking enzymes in plants,play key roles in photosynthesis and abiotic/biotic stress responses;however,evidence concerning the genetics underlying how TGase improve...Transglutaminases(TGases),which are widespread cross-linking enzymes in plants,play key roles in photosynthesis and abiotic/biotic stress responses;however,evidence concerning the genetics underlying how TGase improves the capability of photosynthesis and the mechanism of TGase-mediated photosynthesis are not clear in this crop species.In this study,we clarified the function of TGase in the regulation of photosynthesis in tomato by comparing wild-type(WT)plants,tgase mutants generated by the CRISPR/Cas9 system and TGase-overexpressing(TGaseOE)plants.Our results showed that increasing the transcript level of TGase resulted in an enhanced net photosynthetic rate(Pn),whereas the tgase mutants presented significantly inhibited Pns and CO2 assimilation compared with the WT.Although the total RuBisCO activity was not affected by TGase,the initial and activation status of RuBisCO and the activity of RuBisCO activase(RCA)and fructose-1,6-bisphosphatase(FBPase)in TGaseOE plants were significantly higher than that in WT plants.Except for RuBisCO small subunit(RbcS),the transcription levels of Benson–Calvin cycle-related genes were positively related to the endogenous TGase activity.Furthermore,TGaseOE plants had higher protein levels of RuBisCO large subunit(RbcL)and RCA than did WT plants and showed a reduced redox status by enhancing the activity of dehydroascorbate reductase(DHAR)and glutathione reductase(GR),which was compromised in TGasedeficient plants.Overall,TGase positively regulated photosynthesis by maintaining the activation states of the Benson–Calvin cycle and inducing changes in cellular redox homeostasis in tomato.展开更多
Cotton(Gossypium hirsutum L.)is one of the world’s most important commercial crops.However,the dynamics of metabolite abundance and potential regulatory networks throughout its life cycle remain poorly understood.In ...Cotton(Gossypium hirsutum L.)is one of the world’s most important commercial crops.However,the dynamics of metabolite abundance and potential regulatory networks throughout its life cycle remain poorly understood.In this study,we developed a cotton metabolism regulatory network(CMRN)that spans various developmental stages and encompasses 2138 metabolites and 90309 expressed genesin upland cotton.By integrating high-resolution spatiotemporal metabolome and transcriptome data,we identified 1958 differentially accumulated metabolites and 13597 co-expressed differentially expressed genes between the dwarf mutant pagoda1 and its wild-type counterpart Zhongmiansuo 24.These metabolites and genes were categorized into seven clusters based on tissue-specific accumulation patterns and gene expression profiles across different developmental stages.Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed significant differential enrichment in the fatty acid elongation pathway,particularly in fibers.The differential involvement of genes and metabolites in very-long-chain fatty acid(VLCFA)synthesis led to the identification of GhKCS1b_Dt as a key gene.Overexpression of GhKCS1b_Dt significantly promoted fiber elongation,while its silencing markedly inhibited cotton fiber growth,affirming its positive regulatory role in fiber elongation.This dataset provides a valuable resource for further research into metabolic pathways and gene regulatory networks,offering novel insights for advancing cotton breeding strategies.展开更多
Muscle strength(MS)is related to our neural and muscle systems,essential for clinical diagnosis and rehabilitation evaluation.Although emerging wearable technology seems promising for MS assessment,problems still exis...Muscle strength(MS)is related to our neural and muscle systems,essential for clinical diagnosis and rehabilitation evaluation.Although emerging wearable technology seems promising for MS assessment,problems still exist,including inaccuracy,spatiotemporal differences,and analyzing methods.In this study,we propose a wearable device consisting of myoelectric and strain sensors,synchronously acquiring surface electromyography and mechanical signals at the same spot during muscle activities,and then employ a deep learning model based on temporal convolutional network(TCN)+Transformer(Tcnformer),achieving accurate grading and prediction of MS.Moreover,by combining with deep clustering,named Tcnformer deep cluster(TDC),we further obtain a 25-level classification for MS assessment,refining the conventional 5 levels.Quantification and validation showcase a patient's postoperative recovery from level 3.2 to level 3.6 in the first few days after surgery.We anticipate that this system will importantly advance precise MS assessment,potentially improving relevant clinical diagnosis and rehabilitation outcomes.展开更多
The existing plastic greenhouses in the Yangtze River Basin experience high temperatures in summer and low temperatures in winter,significantly impacting year-round greenhouse production.Double-layer plastic film gree...The existing plastic greenhouses in the Yangtze River Basin experience high temperatures in summer and low temperatures in winter,significantly impacting year-round greenhouse production.Double-layer plastic film greenhouses possess excellent thermal insulation in winter but suffer from high temperatures in summer.Spray cooling is an effective method for reducing summer temperatures in greenhouses,yet direct spraying increases the indoor humidity,which is detrimental to crop growth.To address these problems,the research team designed a double-layer spray greenhouse in which a spray system composed of nozzles was placed between the two layers of plastic films.This paper simulated the indoor temperature field of a greenhouse under different nozzle layouts using Computational Fluid Dynamics(CFD)software to identify the optimal spray system.Based on this analysis,the practical effectiveness of a double-layer spray greenhouse was examined,thereby providing theoretical justification for its promotion and application.The key findings are as follows:1)When the nozzle spacing was 0.8 m,the nozzle was placed 0.2 m from the inner arch top,and the nozzle sprayed downwards,the average temperature inside the greenhouse was the lowest,representing the optimal nozzle layout.2)Compared to a single-layer multispan greenhouse,the double-layer spray greenhouse had a higher average indoor temperature of 1.18℃ in spring,with a lower average indoor temperature of 2.14℃ in summer.The growth,yield,and fruit quality(soluble solids content,vitamin C content,and soluble sugar content)of tomatoes in the double-layer spray greenhouse were superior to those in the single-layer multispan greenhouse.展开更多
基金supported by the National Natural Science Foundation of China(61472005,61201252)CERNET Innovation Project(NGII20160207)
文摘Online fault detection is one of the key technologies to improve the performance of cloud systems. The current data of cloud systems is to be monitored, collected and used to reflect their state. Its use can potentially help cloud managers take some timely measures before fault occurrence in clouds. Because of the complex structure and dynamic change characteristics of the clouds, existing fault detection methods suffer from the problems of low efficiency and low accuracy. In order to solve them, this work proposes an online detection model based on asystematic parameter-search method called SVM-Grid, whose construction is based on a support vector machine(SVM). SVM-Grid is used to optimize parameters in SVM. Proper attributes of a cloud system's running data are selected by using Pearson correlation and principal component analysis for the model. Strategies of predicting cloud faults and updating fault sample databases are proposed to optimize the model and improve its performance.In comparison with some representative existing methods, the proposed model can achieve more efficient and accurate fault detection for cloud systems.
基金This work was financially supported by the National Natural Science Foundation of China(No.31672199,No.31471869,and No.31401919)the China Agriculture Research System(CARS-23-B12)+1 种基金the Central Research Institutes of Basic Research Fund(KYZ201738)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Various biotic and abiotic stresses threaten the cultivation of future agricultural crops.Among these stresses,heat stress is a major abiotic stress that substantially reduces agricultural productivity.Many strategies to enhance heat stress tolerance of crops have been developed,among which is grafting.Here,we show that Momordica-grafted cucumber scions have intrinsically enhanced chlorophyll content,leaf area,and net photosynthetic rate under heat stress compared to plants grafted onto cucumber rootstock.To investigate the mechanisms by which Momordica rootstock enhanced cucumber scions heat stress tolerance,comparative proteomic analysis of cucumber leaves in response to rootstock-grafting and/or heat stress was conducted.Seventy-seven differentially accumulated proteins involved in diverse biological processes were identified by two-dimensional electrophoresis(2-DE)in conjunction with matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry(MALDI-TOF/TOF MS).The following four main categories of proteins were involved:photosynthesis(42.8%),energy and metabolism(18.2%),defense response(14.3%),and protein and nucleic acid biosynthesis(11.7%).Proteomic analysis revealed that scions grafted onto Momordica rootstocks upregulated more proteins involved in photosynthesis compared to scions grafted onto cucumber rootstocks under heat stress and indicated enhanced photosynthetic capacity when seedlings were exposed to heat stress.Furthermore,the expression of photosynthesis-related genes in plants grafted onto Momordica rootstocks significantly increased in response to heat stress.In addition,increased high-temperature tolerance of plants grafted onto Momordica rootstock was associated with the accumulation of ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)and oxygen-evolving enhancer protein 1(OEE1).Taken together,the data indicated that Momordica rootstock might alleviate growth inhibition caused by heat stress by improving photosynthesis,providing valuable insight into enhancing heat stress tolerance in the global warming epoch.
基金the National Key Research and Development Program of China(2018YFD1000800)the National Natural Science Foundation of China(No.31672199 and No.31471869)the China Agriculture Research System(CARS-23-B12).
文摘In plants and algae,PGR5-dependent cyclic electron flow(CEF)is an important regulator of acclimation to fluctuating environments,but how PGR5 participates in CEF is unclear.In this work,we analyzed two PGR5s in cucumber(Cucumis sativus L.)under different conditions and found that CsPGR5a played the dominant role in PGR5-dependent CEF.The results of yeast two-hybrid,biomolecular fluorescence complementation(BiFC),blue native PAGE,and coimmunoprecipitation(CoIP)assays showed that PGR5a interacted with PetC,Lhcb3,and PsaH.Furthermore,the intensity of the interactions was dynamic during state transitions,and the abundance of PGR5 attached to cyt b_(6)f decreased during the transition from state 1 to state 2,which revealed that the function of PGR5a is related to the state transition.We proposed that PGR5 is a small mobile protein that functions when attached to protein complexes.
基金supported by the National Key Research and Development Program of China(2019YFD1001902).
文摘Putrescine(Put),melatonin(MT),proline(Pro),and potassium fulvic acid(MFA)are widely used as plant growth regulators to enhance stress tolerance.However,the roles of their mixtures in response to stress are largely unknown.Here,we mixed Put with MT,Pro,and MFA(hereafter referred to as Put mixture)with different concentrations and foliar sprayed at different growth stages(seedling,flowering,and fruiting stage)of cucumber(Cucumis sativus L.)to investigate their roles on plant growth,fruit yield,and quality under high temperature stress.The foliar application of the Put mixture promoted cucumber growth,increased chlorophyll and Pro contents and net photosynthesis rate,and reduced the values of relative electrolyte leakage,H_(2)O_(2)and malondialdehyde contents of cucumber leaves,indicating that treatment with Put mixture reduced the oxidative stress caused by high temperature.Furthermore,Put mixture-treated cucumber plants had lower fruit deformity rate and higher fruit yield compared with control.The contents of vitamin C and soluble solids of cucumber fruit significantly increased and the contents of tannin and organic acid decreased.The most profound effects were found in the plants treated with 8 mmol L^(−1)Put,50μmol L^(−1)MT,1.5 mmol L^(−1)Pro and 0.3 g L^(−1)MFA every 7 d,three times at the seedling stage,indicating that cucumber seedlings treated with the mixture of Put,MT,Pro,and MFA significantly alleviated the negative effects of high temperature stress.
基金supported by the China Agriculture Research System (CARS-23-B12).
文摘Plants,as sessile in nature,are constantly confronted with diverse biotic and abiotic stresses throughout their life cycle in the changing environment.As a result,plants evolved root-shoot communications to optimize plant growth and development,and regulate responses to environmental stresses.Here,we examined the roles of root-sourced cytokinin(CTK)response to heat stress in grafted cucumber seedlings.Cucumber plants grafted onto cucumber roots and bitter gourd(Momordica charantia)roots were exposed to heat to examine their heat tolerance by assessing the levels of photosynthetic capacity,CTK contents,chlorophyll-a/b-binding protein(Lhcb2),ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)and its activating enzyme(RCA)content,and the enzyme activity of Rubisco.Bitter gourd rootstock enhanced cucumber scions heat stress tolerance.This enhancement was positively correlated with a higher content of CTK in both leaf and root parts,chlorophyll contents,and Rubisco abundance and activity.In addition,the higher level of CTK and Rubisco content in bitter gourd grafted plants shoots than in cucumber self-gafted plants shoots were attributed to an increase in CTK transport from roots in grafted plants under hightemperature conditions.These results indicated that CTK transfer from bitter gourd rootstock to scion and triggered the accumulation of Rubisco in leaf,thus improving the heat resistance of bitter gourd-grafted plants.
基金supported by the National Natural Science Foundation of China(31672199 and 31801902)the China Earmarked Fund for Modern Agro-industry Technology Research System(CARS-23-B12)the Fundamental Research Funds for the Central Universities(KJQN201928).
文摘Transglutaminases(TGases),which are widespread cross-linking enzymes in plants,play key roles in photosynthesis and abiotic/biotic stress responses;however,evidence concerning the genetics underlying how TGase improves the capability of photosynthesis and the mechanism of TGase-mediated photosynthesis are not clear in this crop species.In this study,we clarified the function of TGase in the regulation of photosynthesis in tomato by comparing wild-type(WT)plants,tgase mutants generated by the CRISPR/Cas9 system and TGase-overexpressing(TGaseOE)plants.Our results showed that increasing the transcript level of TGase resulted in an enhanced net photosynthetic rate(Pn),whereas the tgase mutants presented significantly inhibited Pns and CO2 assimilation compared with the WT.Although the total RuBisCO activity was not affected by TGase,the initial and activation status of RuBisCO and the activity of RuBisCO activase(RCA)and fructose-1,6-bisphosphatase(FBPase)in TGaseOE plants were significantly higher than that in WT plants.Except for RuBisCO small subunit(RbcS),the transcription levels of Benson–Calvin cycle-related genes were positively related to the endogenous TGase activity.Furthermore,TGaseOE plants had higher protein levels of RuBisCO large subunit(RbcL)and RCA than did WT plants and showed a reduced redox status by enhancing the activity of dehydroascorbate reductase(DHAR)and glutathione reductase(GR),which was compromised in TGasedeficient plants.Overall,TGase positively regulated photosynthesis by maintaining the activation states of the Benson–Calvin cycle and inducing changes in cellular redox homeostasis in tomato.
基金supported by the National Natural Science Foundation of China(grants 32441062,32360509,32301888,and 32350410409)the National Key Laboratory of Cotton Bio-breeding and Integrated Uti-lization(CBIU2024004)+4 种基金the Xinjiang Science and Technological Pro-gram(the Tianshan Talent Training Program[grant 2022TSYCCX0087]the Key Research and Development Program of Xinjiang[grant 2022B02052]the Natural Science Foundation of Xinjiang Uygur Autonomous Region[grants 2022D01E08 and 2024D01A150])the Xinjiang Science and Technology Major Project of China(grant 2024A02002)the Natural Science Foundation of Henan Province(grant 232300421253).
文摘Cotton(Gossypium hirsutum L.)is one of the world’s most important commercial crops.However,the dynamics of metabolite abundance and potential regulatory networks throughout its life cycle remain poorly understood.In this study,we developed a cotton metabolism regulatory network(CMRN)that spans various developmental stages and encompasses 2138 metabolites and 90309 expressed genesin upland cotton.By integrating high-resolution spatiotemporal metabolome and transcriptome data,we identified 1958 differentially accumulated metabolites and 13597 co-expressed differentially expressed genes between the dwarf mutant pagoda1 and its wild-type counterpart Zhongmiansuo 24.These metabolites and genes were categorized into seven clusters based on tissue-specific accumulation patterns and gene expression profiles across different developmental stages.Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed significant differential enrichment in the fatty acid elongation pathway,particularly in fibers.The differential involvement of genes and metabolites in very-long-chain fatty acid(VLCFA)synthesis led to the identification of GhKCS1b_Dt as a key gene.Overexpression of GhKCS1b_Dt significantly promoted fiber elongation,while its silencing markedly inhibited cotton fiber growth,affirming its positive regulatory role in fiber elongation.This dataset provides a valuable resource for further research into metabolic pathways and gene regulatory networks,offering novel insights for advancing cotton breeding strategies.
基金supported by The Youth Innovation Promotion Association,CAS,and Key Clinical Projects of Peking University Third Hospital(no.BYSYZD2023004)This study was conducted with approval from the Peking University Third Hospital Medical Science Research Ethics Committee(no.M2021091)all patients were fully informed and provided written consent prior to participation.
文摘Muscle strength(MS)is related to our neural and muscle systems,essential for clinical diagnosis and rehabilitation evaluation.Although emerging wearable technology seems promising for MS assessment,problems still exist,including inaccuracy,spatiotemporal differences,and analyzing methods.In this study,we propose a wearable device consisting of myoelectric and strain sensors,synchronously acquiring surface electromyography and mechanical signals at the same spot during muscle activities,and then employ a deep learning model based on temporal convolutional network(TCN)+Transformer(Tcnformer),achieving accurate grading and prediction of MS.Moreover,by combining with deep clustering,named Tcnformer deep cluster(TDC),we further obtain a 25-level classification for MS assessment,refining the conventional 5 levels.Quantification and validation showcase a patient's postoperative recovery from level 3.2 to level 3.6 in the first few days after surgery.We anticipate that this system will importantly advance precise MS assessment,potentially improving relevant clinical diagnosis and rehabilitation outcomes.
基金supported by the Open Project of Xinjiang Production&Construction Corps Key Laboratory of Protected Agriculture(Grant No.NJSS2024102)the Science and Technology Plan Project of the First Division,Aral City(Grant No.2022NY07).
文摘The existing plastic greenhouses in the Yangtze River Basin experience high temperatures in summer and low temperatures in winter,significantly impacting year-round greenhouse production.Double-layer plastic film greenhouses possess excellent thermal insulation in winter but suffer from high temperatures in summer.Spray cooling is an effective method for reducing summer temperatures in greenhouses,yet direct spraying increases the indoor humidity,which is detrimental to crop growth.To address these problems,the research team designed a double-layer spray greenhouse in which a spray system composed of nozzles was placed between the two layers of plastic films.This paper simulated the indoor temperature field of a greenhouse under different nozzle layouts using Computational Fluid Dynamics(CFD)software to identify the optimal spray system.Based on this analysis,the practical effectiveness of a double-layer spray greenhouse was examined,thereby providing theoretical justification for its promotion and application.The key findings are as follows:1)When the nozzle spacing was 0.8 m,the nozzle was placed 0.2 m from the inner arch top,and the nozzle sprayed downwards,the average temperature inside the greenhouse was the lowest,representing the optimal nozzle layout.2)Compared to a single-layer multispan greenhouse,the double-layer spray greenhouse had a higher average indoor temperature of 1.18℃ in spring,with a lower average indoor temperature of 2.14℃ in summer.The growth,yield,and fruit quality(soluble solids content,vitamin C content,and soluble sugar content)of tomatoes in the double-layer spray greenhouse were superior to those in the single-layer multispan greenhouse.
