为探明热带海绵可培养共附生真菌的多样性,本研究以采集自三亚海域的5种热带海绵样品为研究对象,采用4种不同的分离培养基对其共附生真菌进行分离,并进一步利用r DNA ITS序列对可培养的真菌进行分子鉴定和系统发育分析.研究结果表明:热...为探明热带海绵可培养共附生真菌的多样性,本研究以采集自三亚海域的5种热带海绵样品为研究对象,采用4种不同的分离培养基对其共附生真菌进行分离,并进一步利用r DNA ITS序列对可培养的真菌进行分子鉴定和系统发育分析.研究结果表明:热带海绵具有较丰富的真菌资源,5种样品4种分离培养基共分离得到33株真菌,r DNA ITS序列表明,它们分属于13个属,其中Trichoderma为优势种属,本研究分离得到的Hortaea、Westerdykella、Wickerhamomyces、Valsaria、Paraphaeosphaeria、Allocryptovalsa、Cystobasidium等在前人的研究中较为少见或尚未发现.展开更多
In this study,a novel bio-based thermosetting system has been developed from epoxy resin(EP),with rosin-sourced anhydrides(maleopimaric acid,RAM) as curing agent and imidazole type latent catalyst(two amino imidazole ...In this study,a novel bio-based thermosetting system has been developed from epoxy resin(EP),with rosin-sourced anhydrides(maleopimaric acid,RAM) as curing agent and imidazole type latent catalyst(two amino imidazole salt complex,IMA),to be used as matrix for hot-melt prepreg curing at mid-temperature.For comparison,the epoxy resin system with petroleum sourced hardener methylhexahydrophthalicanhydride(MHHPA) was also examined.The curing behaviour and mechanism were investigated by non-isothermal differential scanning calorimeter(DSC) analysis and Fourier transform infrared(FTIR) spectra.The results showed that the curing course of bio-based epoxy resin system containing RAM included two stages,which were the reaction between the free carboxyl group of RAM and oxirane ring under the acceleration of IMA,and the main reaction attributed to the reaction between anhydride and oxirane.According to Kissinger method,the reaction activation energy(E_a) of two stages were 68.9 and 86.5kJmol^(-1),respectively.The E_a of EP/MHHPA and EP/IMA resin system were 81.04 and 77.9kJmol^(-1).The processing property of EP/RAM/IMA system,i.e.the relationship between viscosity-temperature-time,was characterized by cone-plate viscometer aim to decide the processing parameter of prepreg preparation.The effect of RAM content on mechanical performance and dynamic mechanical property was investigated.Noteworthily,compared with the laminates with EP/MHITPA as matrix,the laminates with RAM as hardeners achieved a 44%,73% and 70℃ increase in bending strength,bending modulus and the glass transition temperature,respectively,due to the bulky hydrogenated phenanthrene ring structure incorporated into the cross-linking networks.When the fiber volume fraction reached 47%,the mechanical property of the laminates prepared with hot melt prepreg was superior or comparable to that of composites with pure petroleum sourced matrix.RAM as cross-linking agent of epoxy resin holds a great potential to satisfy the requirement of composites such as structure and secondary structure parts preparation.展开更多
文摘为探明热带海绵可培养共附生真菌的多样性,本研究以采集自三亚海域的5种热带海绵样品为研究对象,采用4种不同的分离培养基对其共附生真菌进行分离,并进一步利用r DNA ITS序列对可培养的真菌进行分子鉴定和系统发育分析.研究结果表明:热带海绵具有较丰富的真菌资源,5种样品4种分离培养基共分离得到33株真菌,r DNA ITS序列表明,它们分属于13个属,其中Trichoderma为优势种属,本研究分离得到的Hortaea、Westerdykella、Wickerhamomyces、Valsaria、Paraphaeosphaeria、Allocryptovalsa、Cystobasidium等在前人的研究中较为少见或尚未发现.
基金supported by the China-EU co-funded project ECO-COMPASS(Grant No.MJ2015-HG-103)
文摘In this study,a novel bio-based thermosetting system has been developed from epoxy resin(EP),with rosin-sourced anhydrides(maleopimaric acid,RAM) as curing agent and imidazole type latent catalyst(two amino imidazole salt complex,IMA),to be used as matrix for hot-melt prepreg curing at mid-temperature.For comparison,the epoxy resin system with petroleum sourced hardener methylhexahydrophthalicanhydride(MHHPA) was also examined.The curing behaviour and mechanism were investigated by non-isothermal differential scanning calorimeter(DSC) analysis and Fourier transform infrared(FTIR) spectra.The results showed that the curing course of bio-based epoxy resin system containing RAM included two stages,which were the reaction between the free carboxyl group of RAM and oxirane ring under the acceleration of IMA,and the main reaction attributed to the reaction between anhydride and oxirane.According to Kissinger method,the reaction activation energy(E_a) of two stages were 68.9 and 86.5kJmol^(-1),respectively.The E_a of EP/MHHPA and EP/IMA resin system were 81.04 and 77.9kJmol^(-1).The processing property of EP/RAM/IMA system,i.e.the relationship between viscosity-temperature-time,was characterized by cone-plate viscometer aim to decide the processing parameter of prepreg preparation.The effect of RAM content on mechanical performance and dynamic mechanical property was investigated.Noteworthily,compared with the laminates with EP/MHITPA as matrix,the laminates with RAM as hardeners achieved a 44%,73% and 70℃ increase in bending strength,bending modulus and the glass transition temperature,respectively,due to the bulky hydrogenated phenanthrene ring structure incorporated into the cross-linking networks.When the fiber volume fraction reached 47%,the mechanical property of the laminates prepared with hot melt prepreg was superior or comparable to that of composites with pure petroleum sourced matrix.RAM as cross-linking agent of epoxy resin holds a great potential to satisfy the requirement of composites such as structure and secondary structure parts preparation.
