[Objective]The aimed to optimize transformation system for Agrobacterium-mediated green cotton shoot tip and provide reference for genetic engineering-assisted breeding of color cotton. [Method]With shoot tip of natur...[Objective]The aimed to optimize transformation system for Agrobacterium-mediated green cotton shoot tip and provide reference for genetic engineering-assisted breeding of color cotton. [Method]With shoot tip of natural green cotton as receptor and by using Agrobacterium-mediated transformation method,the optimum conditions of regeneration system were obtained. [Result]Combining with vacuum infiltration,3-old-day shoot tips were infected for 10 minutes in Abarobacterium suspension with OD600 value about 0.5 followed by co-culture for 24 h on the medium containing MS＋l mg/L KT,pH value of 5.8. The regeneration culture was conducted in MS medium containing l mg/L KT and increasingly 30,50 and 70 mg/L Kan. The highest transformation frequency was 34.6%,and the positive resistant plantlets of green cotton 9804 were obtained. [Conclusion]Green cotton is more beneficial than white cotton to conduct genetic transformation.展开更多
Alternation of two different modes of action of green chemicals： spinosad and methoxyfenozide to combat Virachola livia on dates in Dakhla Oasis, New Valley, Egypt, were done in 2010 and 2011. Based on infestation le...Alternation of two different modes of action of green chemicals： spinosad and methoxyfenozide to combat Virachola livia on dates in Dakhla Oasis, New Valley, Egypt, were done in 2010 and 2011. Based on infestation levels in fruit, the three spray programs including rotations with spinosad 24 SC at 20 mL/100 L were not significantly different. Based on minimum effective rotation doses, alternation of spinosad at 20 mL/100 L followed by methoxyfenozide 24 SC at 15 mL/100 L on a three-week interval showed 0.3% and 0.6% infestation, before harvest for 2010 and 2011, respectively, compared to check treatments which showed 33% and 70% infestations. Also, successful penetration and survival of V. livia （% live larvae） into the fruit by following a spinosad and methoxyfenozide rotation program resulted in 1.8% and 1% larvae, before harvest in 2010 and 2011, respectively, compared to fhait infestation levels of 97% and 89% in the untreated in 2010 and 2011, respectively. Fruit were penetrated by first instar larvae upon hatching, in case no chemical treatment. The last data reflect the excellent performance of this rotation. During the same period, reduction of the three rotation programs was 97.8%-100% and 99%-100% for 2010 and 2011, respectively. Both products proved to be working under dry hot temperatures in these areas.展开更多
Photoredox catalysis has become an indispensable solution for the synthesis of small organic molecules.However,the precise construction of single-atomic active sites not only determines the catalytic performance,but a...Photoredox catalysis has become an indispensable solution for the synthesis of small organic molecules.However,the precise construction of single-atomic active sites not only determines the catalytic performance,but also avails the understanding of structure–activity relationship.Herein,we develop a facile approach to immobilize single-atom Ni sites anchored porous covalent organic framework(COF)by use of 4,4',4''-(1,3,5-triazine-2,4,6-triyl)trianiline and 2,6-diformylpyridine(Ni SAS/TD-COF).Ni SAS/TDCOF catalyst achieves excellent catalytic performance in visible-light-driven catalytic carbon–nitrogen cross-coupling reaction between aryl bromides and amines under mild conditions.The reaction provides amine products in excellent yields(71%–97%)with a wide range of substrates,including aryl and heteroaryl bromides with electron-deficient,electron-rich and neutral groups.Notably,Ni SAS/TD-COF could be recovered from the reaction mixture,corresponding to the negligible loss of photoredox performance after several cycles.This work provides a promising opportunity upon rational design of single-atomic active sites on COFs and the fundamental insight of photoredox mechanism for sustainable organic transformation.展开更多
Poly(dibutyl itaconate-co-isoprene-co-methacrylic acid)(PDIM) elastomer was designed and synthesized by redox emulsion polymerization under mild conditions. PDIM has high molecular weight, relatively high yield, and l...Poly(dibutyl itaconate-co-isoprene-co-methacrylic acid)(PDIM) elastomer was designed and synthesized by redox emulsion polymerization under mild conditions. PDIM has high molecular weight, relatively high yield, and low glass transition temperature(Tg). The structure of PDIM was determined by FTIR and NMR, and the carboxyl content was obtained by titration in a non-proton solvent. Tensile strength and elongation at break increased with increasing carboxyl content. In addition, the interaction between PDIM and silica was elucidated by rubber process analyzer(RPA) and TEM, and the results showed that the silica-PDIM interaction was strong, but the silica-silica interaction was weak.展开更多
With concerns of diminishing fossil fuel reserves and environmental deterioration, great efforts have been made to explore novel approaches of efficiently utilizing bio-renewable feedstocks to produce chemicals and fu...With concerns of diminishing fossil fuel reserves and environmental deterioration, great efforts have been made to explore novel approaches of efficiently utilizing bio-renewable feedstocks to produce chemicals and fuels. 5-Hydroxymethylfurfural(HMF),generated from dehydration of six-carbon ketose, is regarded as a primary and versatile renewable building block to realize the goal of production of these high valued products from renewable biomass resources transformation. In this review, we summarize the recent advances via green routes in the heterogeneous reaction system for the catalytic production of HMF from glucose conversion, and emphasize reaction pathways of these reaction approaches based on the fundamental mechanistic chemistry as well as highlight the challenges(such as separation and purification of products, reusing and regeneration of catalyst, recycling solvent) in this field.展开更多
文摘[Objective]The aimed to optimize transformation system for Agrobacterium-mediated green cotton shoot tip and provide reference for genetic engineering-assisted breeding of color cotton. [Method]With shoot tip of natural green cotton as receptor and by using Agrobacterium-mediated transformation method,the optimum conditions of regeneration system were obtained. [Result]Combining with vacuum infiltration,3-old-day shoot tips were infected for 10 minutes in Abarobacterium suspension with OD600 value about 0.5 followed by co-culture for 24 h on the medium containing MS＋l mg/L KT,pH value of 5.8. The regeneration culture was conducted in MS medium containing l mg/L KT and increasingly 30,50 and 70 mg/L Kan. The highest transformation frequency was 34.6%,and the positive resistant plantlets of green cotton 9804 were obtained. [Conclusion]Green cotton is more beneficial than white cotton to conduct genetic transformation.
文摘Alternation of two different modes of action of green chemicals： spinosad and methoxyfenozide to combat Virachola livia on dates in Dakhla Oasis, New Valley, Egypt, were done in 2010 and 2011. Based on infestation levels in fruit, the three spray programs including rotations with spinosad 24 SC at 20 mL/100 L were not significantly different. Based on minimum effective rotation doses, alternation of spinosad at 20 mL/100 L followed by methoxyfenozide 24 SC at 15 mL/100 L on a three-week interval showed 0.3% and 0.6% infestation, before harvest for 2010 and 2011, respectively, compared to check treatments which showed 33% and 70% infestations. Also, successful penetration and survival of V. livia （% live larvae） into the fruit by following a spinosad and methoxyfenozide rotation program resulted in 1.8% and 1% larvae, before harvest in 2010 and 2011, respectively, compared to fhait infestation levels of 97% and 89% in the untreated in 2010 and 2011, respectively. Fruit were penetrated by first instar larvae upon hatching, in case no chemical treatment. The last data reflect the excellent performance of this rotation. During the same period, reduction of the three rotation programs was 97.8%-100% and 99%-100% for 2010 and 2011, respectively. Both products proved to be working under dry hot temperatures in these areas.
基金supported by the National Natural Science Foundation of China(21972015 and 22088102)Young top talents project of Liaoning Province(XLYC1907147)+1 种基金the Liaoning Revitalization Talent Program(XLYC2008032)the Fundamental Research Funds for the Central Universities(DUT22LAB602)。
文摘Photoredox catalysis has become an indispensable solution for the synthesis of small organic molecules.However,the precise construction of single-atomic active sites not only determines the catalytic performance,but also avails the understanding of structure–activity relationship.Herein,we develop a facile approach to immobilize single-atom Ni sites anchored porous covalent organic framework(COF)by use of 4,4',4''-(1,3,5-triazine-2,4,6-triyl)trianiline and 2,6-diformylpyridine(Ni SAS/TD-COF).Ni SAS/TDCOF catalyst achieves excellent catalytic performance in visible-light-driven catalytic carbon–nitrogen cross-coupling reaction between aryl bromides and amines under mild conditions.The reaction provides amine products in excellent yields(71%–97%)with a wide range of substrates,including aryl and heteroaryl bromides with electron-deficient,electron-rich and neutral groups.Notably,Ni SAS/TD-COF could be recovered from the reaction mixture,corresponding to the negligible loss of photoredox performance after several cycles.This work provides a promising opportunity upon rational design of single-atomic active sites on COFs and the fundamental insight of photoredox mechanism for sustainable organic transformation.
基金supported by the National Natural Science Foundation of China(50933001,51221102)the National Science Fund for Distinguished Young Scholars(50725310)+3 种基金the National Basic Research Program of China(2011 CB606003)the Beijing Nova Program(Z131102000413015)the Beijing Municipal Training Program Foundation for the Talents(2013D003034 00041)the Goodyear Tire & Rubber Company
文摘Poly(dibutyl itaconate-co-isoprene-co-methacrylic acid)(PDIM) elastomer was designed and synthesized by redox emulsion polymerization under mild conditions. PDIM has high molecular weight, relatively high yield, and low glass transition temperature(Tg). The structure of PDIM was determined by FTIR and NMR, and the carboxyl content was obtained by titration in a non-proton solvent. Tensile strength and elongation at break increased with increasing carboxyl content. In addition, the interaction between PDIM and silica was elucidated by rubber process analyzer(RPA) and TEM, and the results showed that the silica-PDIM interaction was strong, but the silica-silica interaction was weak.
基金supported by the National Natural Science Foundation of China(91545103,21273071,21403065)the Commission of Science and Technology of Shanghai Municipality(10dz2220500)
文摘With concerns of diminishing fossil fuel reserves and environmental deterioration, great efforts have been made to explore novel approaches of efficiently utilizing bio-renewable feedstocks to produce chemicals and fuels. 5-Hydroxymethylfurfural(HMF),generated from dehydration of six-carbon ketose, is regarded as a primary and versatile renewable building block to realize the goal of production of these high valued products from renewable biomass resources transformation. In this review, we summarize the recent advances via green routes in the heterogeneous reaction system for the catalytic production of HMF from glucose conversion, and emphasize reaction pathways of these reaction approaches based on the fundamental mechanistic chemistry as well as highlight the challenges(such as separation and purification of products, reusing and regeneration of catalyst, recycling solvent) in this field.
