Aiming at solving the problem of high global warming potential of R134 a,a new mixed refrigerant R13 I1/R152 a(molar fraction ratio of 35:65)with no ozone depletion potential and low global warming potential was propo...Aiming at solving the problem of high global warming potential of R134 a,a new mixed refrigerant R13 I1/R152 a(molar fraction ratio of 35:65)with no ozone depletion potential and low global warming potential was proposed as a substitute for R134 a in automotive air conditioning.The computational models for the thermodynamic properties of R13 I1/R152 a were established by using the PR(Peng-Robinson)equation of state combined with the vdW mixing rule.Based on these models,the cycle performance of this working fluid was calculated,which was also compared with that of R134 a and R1234 yf under the different operating conditions.The results show that R13 I1/R152 a is a near azeotropic refrigerant whose temperature glide is approximately 0,and the saturated vapor pressure curve of which is equivalent to that of R134 a.Moreover,compared to R134 a,R13 I1/R152 a has an average 5.7%improvement in coefficient of performance as well as similar volumetric cooling capacity.The average coefficient of performance and volumetric cooling capacity of R13 I1/R152 a are significantly higher than those of R1234 yf by 13.8%and12.0%,respectively.However,the average discharge temperature of R13 I1/R152 a is approximately13.3 K higher than that of R134 a,but it is also within reasonable limits.Hence,the application of the proposed refrigerant R13 I1/R152 a in automotive air conditioning system is technically feasible.展开更多
The effect of R-styrene-maleic anhydride copolymer （R- SMA） compatibilzation on Nylon 6 （ PA6 ）/polypropylene （ PP ） blends has been investigated experimentally through Molan test, microscopic morphology, and ch...The effect of R-styrene-maleic anhydride copolymer （R- SMA） compatibilzation on Nylon 6 （ PA6 ）/polypropylene （ PP ） blends has been investigated experimentally through Molan test, microscopic morphology, and chemical structure. Results show that the moderate R-SMA addition can promote reaction between anhydride in R-SMA and amino in PA6, and lead to a new PA6-g- R-SMA copolymer in the blends. Such PA6-g-R-SMA eopolymer in the blends can effectively reduce the interfaeial tension and PP particle size, and improve the compatibility of two immiscible phases in the blends. The crystallinity of PA6 in PA6/PP blends has greatly decreased by PP blends. The blends have the best comprehensive mechanical and thermal properties when the mass ratio of PA6/PP/ R-SMA is 90：10：2 to 90：10：4. The impact strength of the PA6/PP blends with the eompatibilizer is increased by more than 150 %.展开更多
Licochalcone A(LCA)is a characteristic compound in licorice Glycyrrhiza inflata and is widely utilized in pharmaceutical and cosmetic industries.However,the biosynthetic pathway and regulatory mechanisms of LCA remain...Licochalcone A(LCA)is a characteristic compound in licorice Glycyrrhiza inflata and is widely utilized in pharmaceutical and cosmetic industries.However,the biosynthetic pathway and regulatory mechanisms of LCA remain poorly understood.In this study,we first found the accumulation of LCA is induced by methyl jasmonate(MeJA).Given that MYB transcriptional factors are well-documented as key regulators of flavonoid biosynthesis,we identified a total of 147 GiR2R3-MYB genes in G.inflata,which were classified into 28 subgroups.The chromosome distributions,sequence characteristics,gene structures,duplication events and cis-acting elements were also investigated.Through integrated analysis of GiR2R3-MYBs expression patterns across different tissues and under MeJA treatment,along with phylogenetic relationship,we identified GiMYB76—a MeJA-inducible MYB transcription factor—as a potential regulator of LCA accumulation.Functional validation showed that transgenic hairy roots overexpressing GiMYB76 exhibited a significant increase in LCA content.DAP-seq analysis of GiMYB76 revealed potential target genes involved in flavonoid biosynthesis regulation.Subsequent promoter activity assay verified that GiMYB76 can bind to the promoter and activate the expression of GiCHS4.Consistently,overexpression of GiCHS4 in G.inflata hairy roots also significantly enhanced LCA production.This study not only clarifies that GiMYB76 transcriptionally activated GiCHS4 to promote LCA biosynthesis but also provides valuable insights for basic research on licorice and the development of related industries.展开更多
Dry fig is a traditional healthy snack and has important economic value in a number of Mediterranean and Middle Eastern countries.Cultivars with no anthocyanin accumulation in the fruit peel are preferred for dry fig ...Dry fig is a traditional healthy snack and has important economic value in a number of Mediterranean and Middle Eastern countries.Cultivars with no anthocyanin accumulation in the fruit peel are preferred for dry fig production.R2R3-MYB transcription factors have promotive or repressive regulatory roles in plant anthocyanin biosynthesis.In this study,113 R2R3-MYB genes were identified in Ficus carica,3 of which were assigned to the S4 subfamily of flavonoid-biosynthesis repressors.FcMYB57 was further recruited as a candidate anthocyaninbiosynthesis repressor based on its sequence features and expression,which was significantly negatively correlated with that of anthocyanin-biosynthesis structural genes.Transient overexpression of FcMYB57 in strawberry totally inhibited fruit pigmentation and significantly increased fruit firmness.The metabolomic analysis confirmed a significant reduction in the contents of cyanidin-3-O-glucoside and pelargonidin-3-O-glucoside,as well as other flavonoids,and transmission electron microscopy revealed an increment in cell-wall thickness.Transcriptome analysis showed downregulation of anthocyanin-biosynthesis structural genes and upregulation of genes related to xylan synthesis.Yeast one-hybrid and dual luciferase assays demonstrated a negative regulatory effect of FcMYB57 on the promoter of FcUFGT3(UDP glucose-flavonoid 3-O-glcosyl-transferase).Yeast two-hybrid assay showed that FcMYB57 does not interact with FcbHLH42,3,14,MYC2,or FcTTG1,all of which have a previously identified or predicted role in flavonoid biosynthesis,however,interaction was detected with FcTPL(Topless),suggesting that FcMYB57 serves as an active repressor of anthocyanin biosynthesis.This is the first identification of an anthocyaninbiosynthesis repressor in fig,with a possible role in fig fruit quality.展开更多
基金supported by the National Natural Science Foundation of China(22068024)。
文摘Aiming at solving the problem of high global warming potential of R134 a,a new mixed refrigerant R13 I1/R152 a(molar fraction ratio of 35:65)with no ozone depletion potential and low global warming potential was proposed as a substitute for R134 a in automotive air conditioning.The computational models for the thermodynamic properties of R13 I1/R152 a were established by using the PR(Peng-Robinson)equation of state combined with the vdW mixing rule.Based on these models,the cycle performance of this working fluid was calculated,which was also compared with that of R134 a and R1234 yf under the different operating conditions.The results show that R13 I1/R152 a is a near azeotropic refrigerant whose temperature glide is approximately 0,and the saturated vapor pressure curve of which is equivalent to that of R134 a.Moreover,compared to R134 a,R13 I1/R152 a has an average 5.7%improvement in coefficient of performance as well as similar volumetric cooling capacity.The average coefficient of performance and volumetric cooling capacity of R13 I1/R152 a are significantly higher than those of R1234 yf by 13.8%and12.0%,respectively.However,the average discharge temperature of R13 I1/R152 a is approximately13.3 K higher than that of R134 a,but it is also within reasonable limits.Hence,the application of the proposed refrigerant R13 I1/R152 a in automotive air conditioning system is technically feasible.
基金Science and Technology Program from Jiangxi Provincial Department of Education,China (No. CJJ10377)
文摘The effect of R-styrene-maleic anhydride copolymer （R- SMA） compatibilzation on Nylon 6 （ PA6 ）/polypropylene （ PP ） blends has been investigated experimentally through Molan test, microscopic morphology, and chemical structure. Results show that the moderate R-SMA addition can promote reaction between anhydride in R-SMA and amino in PA6, and lead to a new PA6-g- R-SMA copolymer in the blends. Such PA6-g-R-SMA eopolymer in the blends can effectively reduce the interfaeial tension and PP particle size, and improve the compatibility of two immiscible phases in the blends. The crystallinity of PA6 in PA6/PP blends has greatly decreased by PP blends. The blends have the best comprehensive mechanical and thermal properties when the mass ratio of PA6/PP/ R-SMA is 90：10：2 to 90：10：4. The impact strength of the PA6/PP blends with the eompatibilizer is increased by more than 150 %.
基金supported by the Guangdong Basic and Applied Basic Research Foundation (2025A1515012679)Open Fund of Shanghai Key Laboratory of Plant Functional Genomics and Resources (PFGR202502)
文摘Licochalcone A(LCA)is a characteristic compound in licorice Glycyrrhiza inflata and is widely utilized in pharmaceutical and cosmetic industries.However,the biosynthetic pathway and regulatory mechanisms of LCA remain poorly understood.In this study,we first found the accumulation of LCA is induced by methyl jasmonate(MeJA).Given that MYB transcriptional factors are well-documented as key regulators of flavonoid biosynthesis,we identified a total of 147 GiR2R3-MYB genes in G.inflata,which were classified into 28 subgroups.The chromosome distributions,sequence characteristics,gene structures,duplication events and cis-acting elements were also investigated.Through integrated analysis of GiR2R3-MYBs expression patterns across different tissues and under MeJA treatment,along with phylogenetic relationship,we identified GiMYB76—a MeJA-inducible MYB transcription factor—as a potential regulator of LCA accumulation.Functional validation showed that transgenic hairy roots overexpressing GiMYB76 exhibited a significant increase in LCA content.DAP-seq analysis of GiMYB76 revealed potential target genes involved in flavonoid biosynthesis regulation.Subsequent promoter activity assay verified that GiMYB76 can bind to the promoter and activate the expression of GiCHS4.Consistently,overexpression of GiCHS4 in G.inflata hairy roots also significantly enhanced LCA production.This study not only clarifies that GiMYB76 transcriptionally activated GiCHS4 to promote LCA biosynthesis but also provides valuable insights for basic research on licorice and the development of related industries.
基金supported by the key research project for fig development of Weiyuan County(Grant No.1002-69199007),China.
文摘Dry fig is a traditional healthy snack and has important economic value in a number of Mediterranean and Middle Eastern countries.Cultivars with no anthocyanin accumulation in the fruit peel are preferred for dry fig production.R2R3-MYB transcription factors have promotive or repressive regulatory roles in plant anthocyanin biosynthesis.In this study,113 R2R3-MYB genes were identified in Ficus carica,3 of which were assigned to the S4 subfamily of flavonoid-biosynthesis repressors.FcMYB57 was further recruited as a candidate anthocyaninbiosynthesis repressor based on its sequence features and expression,which was significantly negatively correlated with that of anthocyanin-biosynthesis structural genes.Transient overexpression of FcMYB57 in strawberry totally inhibited fruit pigmentation and significantly increased fruit firmness.The metabolomic analysis confirmed a significant reduction in the contents of cyanidin-3-O-glucoside and pelargonidin-3-O-glucoside,as well as other flavonoids,and transmission electron microscopy revealed an increment in cell-wall thickness.Transcriptome analysis showed downregulation of anthocyanin-biosynthesis structural genes and upregulation of genes related to xylan synthesis.Yeast one-hybrid and dual luciferase assays demonstrated a negative regulatory effect of FcMYB57 on the promoter of FcUFGT3(UDP glucose-flavonoid 3-O-glcosyl-transferase).Yeast two-hybrid assay showed that FcMYB57 does not interact with FcbHLH42,3,14,MYC2,or FcTTG1,all of which have a previously identified or predicted role in flavonoid biosynthesis,however,interaction was detected with FcTPL(Topless),suggesting that FcMYB57 serves as an active repressor of anthocyanin biosynthesis.This is the first identification of an anthocyaninbiosynthesis repressor in fig,with a possible role in fig fruit quality.
