PM_(1)0 samples were collected from an urban/industrial site nearby Athens,where uncontrolled burning activities occur.PAHs,monocarboxylic,dicarboxylic,hydroxycarboxylic and aromatic acids,tracers from BVOC oxidation,...PM_(1)0 samples were collected from an urban/industrial site nearby Athens,where uncontrolled burning activities occur.PAHs,monocarboxylic,dicarboxylic,hydroxycarboxylic and aromatic acids,tracers from BVOC oxidation,biomass burning tracers and bisphenol A were determined.PAH,monocarboxylic acids,biomass burning tracers and bisphenol A were increased during autumn/winter,while BSOA tracers,dicarboxylic-and hydroxycarboxylic acids during summer.Regarding aromatic acids,different sources and formation mechanisms were indicated as benzoic,phthalic and trimellitic acids were peaked during summer whereas p-toluic,isophthalic and terephthalic were more abundant during autumn/winter.The Benzo[a]pyrene-equivalent carcinogenic power,carcinogenic and mutagenic activities were calculated showing significant(p<0.05)increases during the colder months.Palmitic,succinic and malic acids were the most abundant monocarboxylic,dicarboxylic and hydrocarboxylic acids during the entire sampling period.Isoprene oxidation was the most significant contributor to BSOA as the isoprene-SOA compounds were two times more abundant than the pinene-SOA(13.4±12.3 and 6.1±2.9 ng/m^3,respectively).Ozone has significant impact on the formation of many studied compounds showing significant correlations with:isoprene-SOA(r=0.77),hydrocarboxylic acids(r=0.69),pinene-SOA(r=0.63),dicarboxylic acids(r=0.58),and the sum of phthalic,benzoic and trimellitic acids(r=0.44).PCA demonstrated five factors that could explain sources including plastic enriched waste burning(30.8%),oxidation of unsaturated fatty acids(23.0%),vehicle missions and cooking(9.2%),biomass burning(7.7%)and oxidation of VOCs(5.8%).The results highlight the significant contribution of plastic waste uncontrolled burning to the overall air quality degradation.展开更多
Solving high-temperature plastic mulching film-induced leaf burning in the first week during tobacco cultivation would take much time and effort. In the present study, the growth as well as the leaf sugar and nicotine...Solving high-temperature plastic mulching film-induced leaf burning in the first week during tobacco cultivation would take much time and effort. In the present study, the growth as well as the leaf sugar and nicotine contents of seedlings with or without leaf burning induced by high-temperature plastic mulching film were tested at two independent sites in 2015 and 2016 to identify the influence of leaf burning on seedling growth. The results showed that the growth of seedlings with leaf burning was improved with increased leaf area, leaf number and plant height compared to those without leaf burning, combined with an increased seedling survival rate at two sites in two years. In seedlings with leaf burning, the contents of fructose and glucose increased and peaked at 11：00 and 13：00 in the leaf and root, respectively, with an increased root nicotine content beginning at 13：00, highlighting the signalling role of sugars. Activities of antioxidant enzymes including peroxidase （POD）, superoxide dismutase （SOD） and catalase （CAT） were all increased in seedlings with leaf burning. More plant biomass was allocated to roots in seedlings with leaf burning with increased root volume compared to control seedlings, which might facilitate the absorption of water and nutrients from the soil. Our findings demonstrate that high-temperature plastic mulching film-induced leaf burning not inhibited but benefited seedling survival and growth, suggesting that the time and labour-consuming manual plucking of burnt leaves can be avoided during tobacco cultivation.展开更多
A method is described, that allows a quick and simple testing of the burning behaviour of plastics. It takes into account ignition time as well as afterflame time;properties that are characteristic for the burning beh...A method is described, that allows a quick and simple testing of the burning behaviour of plastics. It takes into account ignition time as well as afterflame time;properties that are characteristic for the burning behaviour of a particular plastic material. The procedure is easy to perform, it does neither require injection-moulded samples nor expensive equipment. The method provides a classification of the burning behaviour. It is especially suitable for a screening of plastic materials complementing established methods like UL-94, GWFI and LOI, and may find application in the development of flame retardants.展开更多
The effects of plasticizers,antioxidants and burning rate modifiers on the aging performance of the composite solid propellant based on hydroxyl-terminated polybutadiene(HTPB)/hexamethylene diisocyanate(HMDI)were expl...The effects of plasticizers,antioxidants and burning rate modifiers on the aging performance of the composite solid propellant based on hydroxyl-terminated polybutadiene(HTPB)/hexamethylene diisocyanate(HMDI)were explored by apply-ing an accelerated aging program for 90 day at 70 ℃. The HTPB propellant matrix with the diisooctyl sebacate(DOS)as plasti-cizers and diisooctyl azelate(DOZ), antioxidants as N,N ′-Diphenyl-p-phenylenediamine(AO) and 2,2′-methylenebis(4-methyl-6-tert-butylphenol)(cyanox 2246)and burning rate modifiers as barium ferrite(BF),copper chromites(CC)and fer-ric oxide(FO)were varied. Results show that sample(S1)which based on DOS decreases the stress value and increases the strain value which considered to be an excellent start for aging program. Sample(S3)containing AO presents the higher resis-tance to oxidation showing the better performance that reflects on increasing the shelf life of the composite solid propellant mo-tor. Sample(S5)which based on BF enhances the ballistic performance among over the other tested two samples. The accelerat-ed aging program allowed us to estimate the motor in-service lifetime.展开更多
AIM：To investigate the effect of allogeneic acellular dermal matrix(ADM) on cograft in joint functional positions of patients with post-burn plastic operation.METHODS:9 patients with hypertrophic acar and joint dysfu...AIM：To investigate the effect of allogeneic acellular dermal matrix(ADM) on cograft in joint functional positions of patients with post-burn plastic operation.METHODS:9 patients with hypertrophic acar and joint dysfunction after severe burns were used.After pre-treating with trypsin and TritonX-100,13 reticulated ADM were overlapped with autogenous ultrathin split-thickness skin grafts(USTS),and were transplanted to the acar excision wounds in the joints of four limbs at the same time.The neighbouring autogenous thin split-thickness skin grafts(TSTS) were used as control.RESULTS:The composite skin grafts as well as the controls were all survived.The rejection and hypertrophic scars were not found during (1-5) years follow-up studies.The apearance,fiber and function of composite skin grafts were near to normal skins.CONCLUSION;The ADM could be used to joint functional positions of patients with post-burn hypertrophicscare and could produce satisfactory plastic results as dermal substitute.展开更多
文摘PM_(1)0 samples were collected from an urban/industrial site nearby Athens,where uncontrolled burning activities occur.PAHs,monocarboxylic,dicarboxylic,hydroxycarboxylic and aromatic acids,tracers from BVOC oxidation,biomass burning tracers and bisphenol A were determined.PAH,monocarboxylic acids,biomass burning tracers and bisphenol A were increased during autumn/winter,while BSOA tracers,dicarboxylic-and hydroxycarboxylic acids during summer.Regarding aromatic acids,different sources and formation mechanisms were indicated as benzoic,phthalic and trimellitic acids were peaked during summer whereas p-toluic,isophthalic and terephthalic were more abundant during autumn/winter.The Benzo[a]pyrene-equivalent carcinogenic power,carcinogenic and mutagenic activities were calculated showing significant(p<0.05)increases during the colder months.Palmitic,succinic and malic acids were the most abundant monocarboxylic,dicarboxylic and hydrocarboxylic acids during the entire sampling period.Isoprene oxidation was the most significant contributor to BSOA as the isoprene-SOA compounds were two times more abundant than the pinene-SOA(13.4±12.3 and 6.1±2.9 ng/m^3,respectively).Ozone has significant impact on the formation of many studied compounds showing significant correlations with:isoprene-SOA(r=0.77),hydrocarboxylic acids(r=0.69),pinene-SOA(r=0.63),dicarboxylic acids(r=0.58),and the sum of phthalic,benzoic and trimellitic acids(r=0.44).PCA demonstrated five factors that could explain sources including plastic enriched waste burning(30.8%),oxidation of unsaturated fatty acids(23.0%),vehicle missions and cooking(9.2%),biomass burning(7.7%)and oxidation of VOCs(5.8%).The results highlight the significant contribution of plastic waste uncontrolled burning to the overall air quality degradation.
基金supported by the Science and Technology Foundation of Guizhou Province,China (20146015-2,20152099 and 20161097)the Special Fund for Excellent Young Talents of Guizhou Province,China (201534)the Foundation of Guizhou Academy of Tobacco Science,China (GZYKS2018-02)
文摘Solving high-temperature plastic mulching film-induced leaf burning in the first week during tobacco cultivation would take much time and effort. In the present study, the growth as well as the leaf sugar and nicotine contents of seedlings with or without leaf burning induced by high-temperature plastic mulching film were tested at two independent sites in 2015 and 2016 to identify the influence of leaf burning on seedling growth. The results showed that the growth of seedlings with leaf burning was improved with increased leaf area, leaf number and plant height compared to those without leaf burning, combined with an increased seedling survival rate at two sites in two years. In seedlings with leaf burning, the contents of fructose and glucose increased and peaked at 11：00 and 13：00 in the leaf and root, respectively, with an increased root nicotine content beginning at 13：00, highlighting the signalling role of sugars. Activities of antioxidant enzymes including peroxidase （POD）, superoxide dismutase （SOD） and catalase （CAT） were all increased in seedlings with leaf burning. More plant biomass was allocated to roots in seedlings with leaf burning with increased root volume compared to control seedlings, which might facilitate the absorption of water and nutrients from the soil. Our findings demonstrate that high-temperature plastic mulching film-induced leaf burning not inhibited but benefited seedling survival and growth, suggesting that the time and labour-consuming manual plucking of burnt leaves can be avoided during tobacco cultivation.
文摘A method is described, that allows a quick and simple testing of the burning behaviour of plastics. It takes into account ignition time as well as afterflame time;properties that are characteristic for the burning behaviour of a particular plastic material. The procedure is easy to perform, it does neither require injection-moulded samples nor expensive equipment. The method provides a classification of the burning behaviour. It is especially suitable for a screening of plastic materials complementing established methods like UL-94, GWFI and LOI, and may find application in the development of flame retardants.
文摘The effects of plasticizers,antioxidants and burning rate modifiers on the aging performance of the composite solid propellant based on hydroxyl-terminated polybutadiene(HTPB)/hexamethylene diisocyanate(HMDI)were explored by apply-ing an accelerated aging program for 90 day at 70 ℃. The HTPB propellant matrix with the diisooctyl sebacate(DOS)as plasti-cizers and diisooctyl azelate(DOZ), antioxidants as N,N ′-Diphenyl-p-phenylenediamine(AO) and 2,2′-methylenebis(4-methyl-6-tert-butylphenol)(cyanox 2246)and burning rate modifiers as barium ferrite(BF),copper chromites(CC)and fer-ric oxide(FO)were varied. Results show that sample(S1)which based on DOS decreases the stress value and increases the strain value which considered to be an excellent start for aging program. Sample(S3)containing AO presents the higher resis-tance to oxidation showing the better performance that reflects on increasing the shelf life of the composite solid propellant mo-tor. Sample(S5)which based on BF enhances the ballistic performance among over the other tested two samples. The accelerat-ed aging program allowed us to estimate the motor in-service lifetime.
文摘AIM：To investigate the effect of allogeneic acellular dermal matrix(ADM) on cograft in joint functional positions of patients with post-burn plastic operation.METHODS:9 patients with hypertrophic acar and joint dysfunction after severe burns were used.After pre-treating with trypsin and TritonX-100,13 reticulated ADM were overlapped with autogenous ultrathin split-thickness skin grafts(USTS),and were transplanted to the acar excision wounds in the joints of four limbs at the same time.The neighbouring autogenous thin split-thickness skin grafts(TSTS) were used as control.RESULTS:The composite skin grafts as well as the controls were all survived.The rejection and hypertrophic scars were not found during (1-5) years follow-up studies.The apearance,fiber and function of composite skin grafts were near to normal skins.CONCLUSION;The ADM could be used to joint functional positions of patients with post-burn hypertrophicscare and could produce satisfactory plastic results as dermal substitute.
