The thermal stress of the quartz oscillator module packaging isinvestigated using digital-im- age correlation method (DICM), and theexperimental results are given. Under the quartz oscillator modulepackaging, the quar...The thermal stress of the quartz oscillator module packaging isinvestigated using digital-im- age correlation method (DICM), and theexperimental results are given. Under the quartz oscillator modulepackaging, the quartz oscillator and the Fe-Sn-Cu alloy frame arejoined together with the electroconductive adhesive (PI), and theelectroconductive adhesive needs to be cured twice at 150 deg. C and275 deg. C respective- ly.展开更多
Three kinds of novel aromatic diamine-based benzoxazines containing naphthalene, propane-2,2-diyldibenzene and neopentyl groups in the backbone, respectively （designated as BAPNCP, BAPBACP and BAPNPGCP, respectively...Three kinds of novel aromatic diamine-based benzoxazines containing naphthalene, propane-2,2-diyldibenzene and neopentyl groups in the backbone, respectively （designated as BAPNCP, BAPBACP and BAPNPGCP, respectively）, were synthesized and characterized. In addition, the effects of backbone structures on curing behaviors of the monomers and thermal and flammability properties of the resulting polymers were systematically studied. The results indicated that BAPNPGCP displayed the highest enthalpy of the curing reaction associated with the ring-opening of benzoxazine, which was due to the effect of benzoxazine ring content per unit mass. Interestingly, the 5 wt% weight loss temperature and char residue after thermogravimetric test for poly（BAPNPGCP） were 8 ℃ and 7% higher than those of poly（BAPBACP）. Meanwhile, the total heat release of poly（BAPNPGCP） was less than half of that for poly（BAPBACP）, indicating the substantial effect of benzoxazine ring content on flammability and char formation. Furthermore, it was found that poly（BAPNCP） gave the best thermal stability and flame retardancy, which was due to the synergistic effect between naphthalene group and benzoxazine ring content. This study provides new insight into the curing behavior of benzoxazine and further understanding on the high performance of polybenzoxazine.展开更多
Postharvest seafood mushroom(Hypsizygus marmoreus)is highly susceptible to rapid dehydration,decay,and softening,rendering single preservation technologies insufficient to effectively address these issues.This study i...Postharvest seafood mushroom(Hypsizygus marmoreus)is highly susceptible to rapid dehydration,decay,and softening,rendering single preservation technologies insufficient to effectively address these issues.This study investigated a complementary strategy by integrating a low-voltage electrostatic field(LVEF)with biodegradable poly(butylene adipate-co-terephthalate)/polylactic acid(PBAT/PLA)packaging to extend the mushroom's shelf life.Results showed that compared with conventional low-density polyethylene(LDPE),PBAT/PLA film effec-tively prevented moisture condensation and maintained lower CO_(2)concentrations.In contrast,LVEF treatment could suppress respiratory intensity,modulate relevant enzyme activity,and significantly mitigate excessive moisture loss caused by PBAT/PLA films.The findings indicated that the combined treatment effectively increased the mushrooms'antioxidant capacity,maintained cell membrane stability,sustained cell wall poly-saccharide levels,and preserved optimal appearance and texture during storage.The combined application of LVEF and PBAT/PLA packaging effectively preserved quality and extended the shelf life at 4℃from 6 to 15 days,offering a promising,eco-friendly strategy for preserving high-respiration edible fungi.展开更多
The average transient lifetime of a chaotic transient versus the Lyapunov dimension of a chaotic saddle is studied for high-dimensional nonlinear dynamical systems. Typically the average lifetime depends upon not only...The average transient lifetime of a chaotic transient versus the Lyapunov dimension of a chaotic saddle is studied for high-dimensional nonlinear dynamical systems. Typically the average lifetime depends upon not only the system parameter but also the Lyapunov dimension of the chaotic saddle. The numerical example uses the delayed feedback differential equation.展开更多
Leather is a collagen-based biomass prepared from raw skins or hides by a series of unit operations, in which the unhairing and fiber opening are extremely important operations. However, the conventional Na2S/Ca(OH)2 ...Leather is a collagen-based biomass prepared from raw skins or hides by a series of unit operations, in which the unhairing and fiber opening are extremely important operations. However, the conventional Na2S/Ca(OH)2 system used in unhairing and fiber opening has given rise to the pollution to the environment. It is necessary to develop substitute technology for the Na2S/Ca(OH)2. In the present study, 1-allyl-3-methylimidazolium chloride ([AMIm]Cl) was used to cooperate with dispase for cycle unhairing and one-pot beamhouse to recycle waste bovine hides and com-pared with conventional processing. During those processes, the mechanism of [AMIm]Cl-dispase synergistic unhair-ing and collagen fibers opening were studied. Besides, plant hazard, organic matter and [AMIm]Cl of wastewater from [AMIm]Cl-dispase process were respectively investigated and separated to evaluate the environmental and economic benefits of the [AMIm]Cl-dispase process. As a result, enzyme activity after unhairing by [AMIm]Cl-diapase system for using 5 times is higher than that by KCl-dispase system, and needs lower unhairing time, which is because of rapid penetration of [AMIm]Cl-dispase solution in bovine hides. For this reason, the tensile strength and elastic modulus of tanned leather from [AMIm]Cl-dispase process are higher than those from the KCl-diapase and conventional pro-cesses, and its hydrothermal shrinkage temperature is comparable to that of the conventional one. Because of the 58.13% lower wastewater discharge (WD), 66.60% lower total solids (TS), 97.23% lower ammonia nitrogen (NH3-N), non-toxic wastewater and organic matter recovery in wastewater are reached from [AMIm]Cl-dispase process, which is expected to be an alternative to the conventional process to reduce environmental pollution and realize the sustainable development of technology for leather manufacturing.展开更多
Plasma-activated water(PAW)is increasingly recognized for its role in mitigating microbial contamination in fresh-cut produce,but its disinfection effectiveness can be limited under certain conditions.Notably,dissolvi...Plasma-activated water(PAW)is increasingly recognized for its role in mitigating microbial contamination in fresh-cut produce,but its disinfection effectiveness can be limited under certain conditions.Notably,dissolving organic acids in PAW is an effective way to boost its antimicrobial properties through a synergistic effect.This study examined the enhanced antimicrobial efficacy of PAW when combined with tartaric acid against Staphylococcus aureus and its application on fresh-cut asparagus lettuce.Results demonstrated that PAW combined with tartaric acid showed stronger antimicrobial efficacy than PAW alone(p<0.05).The addition of tartaric acid to PAW increased the oxidation-reduction potential and lowered the pH,contributing to its superior antimicrobial performance against S.aureus.The underlying antimicrobial mechanisms included the inactivation of Ca^(2+)-Mg^(2+)-ATPase and Na^(+)-K^(+)-ATPase accompanied by damage to bacterial cell membrane,enhanced oxidative damage due to the influx of extracellular reactive oxygen species such as H_(2)O_(2),the disrupted energy metabolic activities,and the mitigated bacterial defense system constructed by antioxidant enzymes,such as superoxide dismutase and catalase.Furthermore,the synergistic treatment improved the quality of fresh-cut asparagus lettuce by retarding browning,curbing microbial spoilage,and lessening weight loss.The preservation of color was largely due to the decreased activities of polyphenol oxidase and peroxidase,along with controlled chlorophyll degradation.These findings suggest that PAW enhanced with tartaric acid could be a promising,cost-effective disinfection strategy for fresh-cut asparagus lettuce.展开更多
To achieve long-term effective protection of food by continuously controlling the release of active substances in an active film,IRMOF-3 was post-synthetic modified with benzoic acid(BA)to obtain BA-IRMOF-3.This modif...To achieve long-term effective protection of food by continuously controlling the release of active substances in an active film,IRMOF-3 was post-synthetic modified with benzoic acid(BA)to obtain BA-IRMOF-3.This modification enhanced the loading capacity of carvacrol(CA)and slowed down its release rate.Research on IRMOF-3 synthesis has found that increasing the proportion of metal nodes can improve its crystallinity.The post-synthesis modification of IRMOF-3 through amide reaction successfully enhanced the binding energy with CA from5.1 kcal/mol to6 kcal/mol,resulting in an improved CA loading rate of 28.62%±0.15%and delayed release.Furthermore,the BA-IRMOF-3/CA assembly was added to the sodium alginate matrix to prepare the active film BMC@SA,which improved the mechanical and physical properties of the film.The release and antibacterial/antioxidant properties were investigated.The results demonstrated that the active film BMC@SA exhibited significant sustained-release properties and antibacterial/antioxidant activities,reducing the growth of E.coli and S.aureus by 61.95%and 49.33%respectively.In refrigerated pork experiments,the film BMC@SA slowed down the color,weight,pH changes and inhibited microbial growth of fresh pork effectively,and extended the shelf life of pork from 6 d to 12 d,which demonstrated the potential application of active film BMC@SA in food preservation.展开更多
基金the Natural Science Foundation of Tianjin (013605211)
文摘The thermal stress of the quartz oscillator module packaging isinvestigated using digital-im- age correlation method (DICM), and theexperimental results are given. Under the quartz oscillator modulepackaging, the quartz oscillator and the Fe-Sn-Cu alloy frame arejoined together with the electroconductive adhesive (PI), and theelectroconductive adhesive needs to be cured twice at 150 deg. C and275 deg. C respective- ly.
基金supported by the National Natural Science Foundation of China(No.51103129)the National Basic Research Program of China("973 Program",No.2010CB631105)+1 种基金the Ningbo Natural Science Foundation(No.2012A610084)the Open Fund of Zhejiang Provincial Top Key Discipline of New Materials and Process Engineering(No.20110939)
文摘Three kinds of novel aromatic diamine-based benzoxazines containing naphthalene, propane-2,2-diyldibenzene and neopentyl groups in the backbone, respectively （designated as BAPNCP, BAPBACP and BAPNPGCP, respectively）, were synthesized and characterized. In addition, the effects of backbone structures on curing behaviors of the monomers and thermal and flammability properties of the resulting polymers were systematically studied. The results indicated that BAPNPGCP displayed the highest enthalpy of the curing reaction associated with the ring-opening of benzoxazine, which was due to the effect of benzoxazine ring content per unit mass. Interestingly, the 5 wt% weight loss temperature and char residue after thermogravimetric test for poly（BAPNPGCP） were 8 ℃ and 7% higher than those of poly（BAPBACP）. Meanwhile, the total heat release of poly（BAPNPGCP） was less than half of that for poly（BAPBACP）, indicating the substantial effect of benzoxazine ring content on flammability and char formation. Furthermore, it was found that poly（BAPNCP） gave the best thermal stability and flame retardancy, which was due to the synergistic effect between naphthalene group and benzoxazine ring content. This study provides new insight into the curing behavior of benzoxazine and further understanding on the high performance of polybenzoxazine.
基金funded by the National Key Research and Development Program of China(2022YFA1203604 and 2023YFF1105200)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX24_2507).
文摘Postharvest seafood mushroom(Hypsizygus marmoreus)is highly susceptible to rapid dehydration,decay,and softening,rendering single preservation technologies insufficient to effectively address these issues.This study investigated a complementary strategy by integrating a low-voltage electrostatic field(LVEF)with biodegradable poly(butylene adipate-co-terephthalate)/polylactic acid(PBAT/PLA)packaging to extend the mushroom's shelf life.Results showed that compared with conventional low-density polyethylene(LDPE),PBAT/PLA film effec-tively prevented moisture condensation and maintained lower CO_(2)concentrations.In contrast,LVEF treatment could suppress respiratory intensity,modulate relevant enzyme activity,and significantly mitigate excessive moisture loss caused by PBAT/PLA films.The findings indicated that the combined treatment effectively increased the mushrooms'antioxidant capacity,maintained cell membrane stability,sustained cell wall poly-saccharide levels,and preserved optimal appearance and texture during storage.The combined application of LVEF and PBAT/PLA packaging effectively preserved quality and extended the shelf life at 4℃from 6 to 15 days,offering a promising,eco-friendly strategy for preserving high-respiration edible fungi.
基金Supported by the Hu'nan Natural Science Foundation(No.SSY2066).
文摘The average transient lifetime of a chaotic transient versus the Lyapunov dimension of a chaotic saddle is studied for high-dimensional nonlinear dynamical systems. Typically the average lifetime depends upon not only the system parameter but also the Lyapunov dimension of the chaotic saddle. The numerical example uses the delayed feedback differential equation.
基金National Natural Science Foundation of China(No.51673177)National Key R&D Program of China(No.2017YFB0308500).
文摘Leather is a collagen-based biomass prepared from raw skins or hides by a series of unit operations, in which the unhairing and fiber opening are extremely important operations. However, the conventional Na2S/Ca(OH)2 system used in unhairing and fiber opening has given rise to the pollution to the environment. It is necessary to develop substitute technology for the Na2S/Ca(OH)2. In the present study, 1-allyl-3-methylimidazolium chloride ([AMIm]Cl) was used to cooperate with dispase for cycle unhairing and one-pot beamhouse to recycle waste bovine hides and com-pared with conventional processing. During those processes, the mechanism of [AMIm]Cl-dispase synergistic unhair-ing and collagen fibers opening were studied. Besides, plant hazard, organic matter and [AMIm]Cl of wastewater from [AMIm]Cl-dispase process were respectively investigated and separated to evaluate the environmental and economic benefits of the [AMIm]Cl-dispase process. As a result, enzyme activity after unhairing by [AMIm]Cl-diapase system for using 5 times is higher than that by KCl-dispase system, and needs lower unhairing time, which is because of rapid penetration of [AMIm]Cl-dispase solution in bovine hides. For this reason, the tensile strength and elastic modulus of tanned leather from [AMIm]Cl-dispase process are higher than those from the KCl-diapase and conventional pro-cesses, and its hydrothermal shrinkage temperature is comparable to that of the conventional one. Because of the 58.13% lower wastewater discharge (WD), 66.60% lower total solids (TS), 97.23% lower ammonia nitrogen (NH3-N), non-toxic wastewater and organic matter recovery in wastewater are reached from [AMIm]Cl-dispase process, which is expected to be an alternative to the conventional process to reduce environmental pollution and realize the sustainable development of technology for leather manufacturing.
基金supported by the fundamental Research Funds for the Central Universities(JUSRP124028)the National Key R&D Program of China(2022YFF1100803)+3 种基金the Modern Agriculture Grant of Key Research and Development Program of Jiangsu Province(BE202331O)the Natural Science Foundation of China(32261133623)the Science and Technology Planning Project of Jiangsu Market Supervision and Administration Bureau(KJ21125006)the Open Project of Engineering Research Center of Dairy Quality and Safety Control Technology of Ministry of Education of China(R202101).
文摘Plasma-activated water(PAW)is increasingly recognized for its role in mitigating microbial contamination in fresh-cut produce,but its disinfection effectiveness can be limited under certain conditions.Notably,dissolving organic acids in PAW is an effective way to boost its antimicrobial properties through a synergistic effect.This study examined the enhanced antimicrobial efficacy of PAW when combined with tartaric acid against Staphylococcus aureus and its application on fresh-cut asparagus lettuce.Results demonstrated that PAW combined with tartaric acid showed stronger antimicrobial efficacy than PAW alone(p<0.05).The addition of tartaric acid to PAW increased the oxidation-reduction potential and lowered the pH,contributing to its superior antimicrobial performance against S.aureus.The underlying antimicrobial mechanisms included the inactivation of Ca^(2+)-Mg^(2+)-ATPase and Na^(+)-K^(+)-ATPase accompanied by damage to bacterial cell membrane,enhanced oxidative damage due to the influx of extracellular reactive oxygen species such as H_(2)O_(2),the disrupted energy metabolic activities,and the mitigated bacterial defense system constructed by antioxidant enzymes,such as superoxide dismutase and catalase.Furthermore,the synergistic treatment improved the quality of fresh-cut asparagus lettuce by retarding browning,curbing microbial spoilage,and lessening weight loss.The preservation of color was largely due to the decreased activities of polyphenol oxidase and peroxidase,along with controlled chlorophyll degradation.These findings suggest that PAW enhanced with tartaric acid could be a promising,cost-effective disinfection strategy for fresh-cut asparagus lettuce.
基金support of the National Key Research&Development Program of China(grant numbers:2018YFC1603200,2018YFC1603202)Taishan Industry Leading Personnel Engineering(no grant number).
文摘To achieve long-term effective protection of food by continuously controlling the release of active substances in an active film,IRMOF-3 was post-synthetic modified with benzoic acid(BA)to obtain BA-IRMOF-3.This modification enhanced the loading capacity of carvacrol(CA)and slowed down its release rate.Research on IRMOF-3 synthesis has found that increasing the proportion of metal nodes can improve its crystallinity.The post-synthesis modification of IRMOF-3 through amide reaction successfully enhanced the binding energy with CA from5.1 kcal/mol to6 kcal/mol,resulting in an improved CA loading rate of 28.62%±0.15%and delayed release.Furthermore,the BA-IRMOF-3/CA assembly was added to the sodium alginate matrix to prepare the active film BMC@SA,which improved the mechanical and physical properties of the film.The release and antibacterial/antioxidant properties were investigated.The results demonstrated that the active film BMC@SA exhibited significant sustained-release properties and antibacterial/antioxidant activities,reducing the growth of E.coli and S.aureus by 61.95%and 49.33%respectively.In refrigerated pork experiments,the film BMC@SA slowed down the color,weight,pH changes and inhibited microbial growth of fresh pork effectively,and extended the shelf life of pork from 6 d to 12 d,which demonstrated the potential application of active film BMC@SA in food preservation.
