Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation ac...Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation activity were studied.Several different carbon materi-als were produced from them by oxida-tion in air(350℃,300 mL/min)fol-lowed by carbonization(1000℃ in Ar),and the effect of the cross-linked structure on their structure and sodium storage properties was investigated.The results showed that the two pitch fractions were obviously different after the air oxidation.The TS fraction with a low degree of condensation and abundant side chains had a stronger oxidation activity and thus introduced more cross-linked oxygen-containing functional groups C(O)―O which prevented carbon layer rearrangement during the carbonization.As a result,a disordered hard carbon with more defects was formed,which improved the electrochemical performance.Therefore,the carbon materials derived from TS(O-TS-1000)had an obvious disordered structure and a larger layer spacing,giving them better sodium storage perform-ance than those derived from the TI-PS fraction(O-TI-PS-1000).The specific capacity of O-TS-1000 was about 250 mAh/g at 20 mA/g,which was 1.67 times higher than that of O-TI-PS-1000(150 mAh/g).展开更多
The magnetization reduction of hematite using biomass waste can effectively utilize waste and reduce CO_(2) emission to achieve the goals of carbon peaking and carbon neutrality.The effects of temperatures on suspensi...The magnetization reduction of hematite using biomass waste can effectively utilize waste and reduce CO_(2) emission to achieve the goals of carbon peaking and carbon neutrality.The effects of temperatures on suspension magnetization roasting of hematite using biomass waste for evolved gases have been investigated using TG-FTIR,Py-GC/MS and gas composition analyzer.The mixture reduction process is divided into four stages.In the temperature range of 200-450℃ for mixture,the release of CO_(2),acids,and ketones is dominated in gases products.The yield and concentration of small molecules reducing gases increase when the temperature increases from 450 to 900℃.At 700℃,the volume concentrations of CO,H_(2) and CH_(4) peak at 8.91%,8.90% and 4.91%,respectively.During the suspension magnetization roasting process,an optimal iron concentrate with an iron grade of 70.86%,a recovery of 98.66% and a magnetic conversion of 45.70% is obtained at 700℃.Therefore,the magnetization reduction could react greatly in the temperature range of 600 to 700℃ owing to the suitable reducing gases.This study shows a detail gaseous evolution of roasting temperature and provides a new insight for studying the reduction process of hematite using biomass waste.展开更多
This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternati...This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternatives for liquid fuel and aviation industry is first discussed.Key insights encompass the evolutionary progression of biofuel production from first-generation to second-generation biofuels,with a focus on utilizing non-food sources like woody biomass for enhanced sustainability.Available data from the literature on techno-economic assessments of various SAF production pathways are analyzed including production costs,conversion efficiency,and scalability.Moreover,results of lifecycle assessments associated with different SAF production pathways are presented,providing essential insights for decision-making processes.The challenges of scaling up woody biomass-based SAF production are discussed based on the assessment results,and recommendations are proposed to steer stakeholders towards a greener and more sustainable trajectory for aviation operations.展开更多
To solve the problem of sealing between the barrel and the rubber ring of shell body during an launching process of aerodynamic extinguishing cannon, a rubber sealing model with bionic dimpled characteristics was esta...To solve the problem of sealing between the barrel and the rubber ring of shell body during an launching process of aerodynamic extinguishing cannon, a rubber sealing model with bionic dimpled characteristics was established based on the theory of bionic dimpled drag reduction and the principle of rubber sealing. In condition that the bionic dimpled characteristic diameters were 1, 2, 3, 4, and 5 mm, respectively, by numerical simulation, the influence of the installing compression of the rubber sealing ring on its surface stress and deformation was analyzed, and sealing performance of the rubber ring with different diameters of bionic dimpled was studied. The results show that the deformation of rubber ring appears prominent nonlinear characteristics when compression is increased from 1.5 mm to 2.5 ram. When the compression is 2.5 mm, the equivalent compression stress on the sealing areas of both sides of the rubber seal is greater than the working pressure of aerodynamic extinguishing cannon, which could meet the sealing requirement and would not cause leakage. So the rubber sealing ring with bionic dimpled surface possesses a good sealing characteristic and has no negative effect on the sealing of shell body; When the compression is 2.5 mm, the larger equivalent stress on the edge of sealing ring and the more even stress distribution in the high pressure area are generated due to the smaller compressive stress on the bionic dimple areas, which lays a foundation for the drag reduction characteristics of the shell body＇s rubber ring with bionic dimpled surface.展开更多
Producer gas through gasification of biomass can be used as an alternate fuel in rural areas due to high potential of biomass resources in India.Experiments were conducted to study the performance of a diesel engine(f...Producer gas through gasification of biomass can be used as an alternate fuel in rural areas due to high potential of biomass resources in India.Experiments were conducted to study the performance of a diesel engine(four stroke,single cylinder,5.25 kW) with respect to its thermal efficiency,specific fuel consumption and diesel substitution by use of diesel alone and producer gas-cum-diesel(dual fuel mode).Three types of biomass,i.e.wood chips,pigeon pea stalks and corn cobs were used for generation of producer gas.A producer gas system consisting of a downdraft gasifier,a cooling cum cleaning unit,a filtering unit and a gas air mixing device was designed,fabricated and used to power a 5.25 kW diesel engine on dual fuel mode.Performance of the engine was reported by keeping biomass moisture contents as 8%,12%,16%,and 21%,engine speed as 1 600 r/min and with variable engine loads.The average value of thermal efficiency on dual fuel mode was found slightly lower than that of diesel mode.The specific diesel consumption was found to be 60%-64% less in dual fuel mode than that in diesel mode for the same amount of energy output.The average diesel substitution of 74% was observed with wood chips followed by corn cobs(78%) and pigeon pea stalks(82%).Based on the performance studied,the producer gas may be used as a substitute or as supplementary fuel for diesel conservation,particularly for stationary engines in agricultural operations in the farm.展开更多
Experiments were conducted to investigate the behavior of the sequential system of intensified zero-valent iron process(IZVI) and anaerobic filter and biological aerated filter(AF/BAF) reactors for advanced treatment ...Experiments were conducted to investigate the behavior of the sequential system of intensified zero-valent iron process(IZVI) and anaerobic filter and biological aerated filter(AF/BAF) reactors for advanced treatment of biologically pretreated coking wastewater. Particular attention was paid to the performance of the integrated system for the removal of chemical oxygen demand(COD), ammonia nitrogen(NH3-N) and total nitrogen(TN). The average removal efficiencies of COD, NH3-N and TN were 76.28%, 96.76% and 59.97%, with the average effluent mass concentrations of 56, 0.53 and 18.83 mg/L, respectively, reaching the first grade of the national discharge standard. Moreover, the results of gas chromatography/mass spectrum(GC/MS) and gel permeation chromatography(GPC) analysis demonstrated that the refractory organic compounds with high relative molecular mass were partly removed in IZVI process by the function of oxidation-reduction, flocculation and adsorption which could also enhance the biodegradability of the system effluent. The removal efficiencies of NH3-N and TN were achieved mainly in the subsequent AF/BAF reactors by nitrification and denitrification. Overall, the results obtained show that the application of IZVI in combination with AF/BAF is a promising technology for advanced treatment of biologically pretreated coking wastewater.展开更多
Reburning was applied to Polish automatic coal-fired retort boiler (25 kW).The use of bio-syngas reduced NOx emissions from the boiler by over 25%,below the significant level of 200 mg/m3 .Reburning was carried out us...Reburning was applied to Polish automatic coal-fired retort boiler (25 kW).The use of bio-syngas reduced NOx emissions from the boiler by over 25%,below the significant level of 200 mg/m3 .Reburning was carried out using an integrated system consisting of the boiler and a fixed-bed 60 kW (GazEla) gasification reactor.The process gas was continuously introduced above the coal burner of the boiler.The process parameters of the boiler and the gasifier were also measured and compared with the other units.Characteristic NOx emissions from automatic and manually operated boilers were also presented.展开更多
The gasification industries make use of biomass residue as feedstock to produce synthesis gas,but the gasification of this waste biomass generates tons of ash everyday.Performance properties and agglomeration behavior...The gasification industries make use of biomass residue as feedstock to produce synthesis gas,but the gasification of this waste biomass generates tons of ash everyday.Performance properties and agglomeration behavior of corncob ash(CCA) collected from the gasification of corncobs in a pilot-scale gasification station were investigated by using some experimental methods.Based on the chemical composition results,the agglomeration tendency of CCA from combustion and gasification process was also analyzed.Chemical analysis shows that the fly ash is mainly composed of inorganic matters formed by K,Mg,Ca,Na,Fe,Al,S,etc.The agglomeration characteristics indicate that the slagging degree increases with the increase of ashing temperature,and the slagging tendency of these CCA samples from gasification or combustion is different with various slagging indices.All CCA samples from combustion or gasification can cause slagging/fouling problems in thermal conversion systems.The applications of CCA are closely related to its performances,and CCA has the potential to be used in various fields,for example,as a material for ceramic products and activated carbon,as an adsorbent,as a crude fertilizer,and as a structural material.展开更多
The process of urbanization affects the urban warming.The change of urban warming was investigated by several urbanization factors in Changsha,China.The data of surface temperature(minimum,maximum and mean) of Changsh...The process of urbanization affects the urban warming.The change of urban warming was investigated by several urbanization factors in Changsha,China.The data of surface temperature(minimum,maximum and mean) of Changsha were analyzed to understand the possible effects of urbanization on the climate of this region owing to the population growth,built-up area expansion and energy consumption increases.The weights of these three factors were calculated by the analytical hierarchy process(AHP).Then,three weights were simulated with nonlinear method to obtain the urbanization development rate which was utilized to reveal the influence of the urbanization factors on the surface temperature.The result shows that there is a significant upward trend in the urban temperatures of Changsha.The temperature increase seems to be closely related to the rate of urbanization between 1993 and 2008,and there is an evidential increase trend of the influence on urban temperature by urbanization during 16 years.It is a quantifiable approach measuring the relationship between urbanization and urban eco-environment,and can be applied for the urban sustainability.展开更多
Generation of polydisperse KCl aerosol with a new salt aerosol generator was investigated, Special attention was paid on particles with diameters between 3 and 10 μm. The main improvement consists of the different ro...Generation of polydisperse KCl aerosol with a new salt aerosol generator was investigated, Special attention was paid on particles with diameters between 3 and 10 μm. The main improvement consists of the different routes of KCl solution droplets. In traditional generators, the solution droplets travel through one cylinder; while in the case analyzed here, after spray atomization, the droplets travel through two cylinders in series. The first cylinder was fed with warm air and the second one with cold air. In such way, the complete evaporation of the water from the droplets can be ensured. The influencing factors of the generated aerosol size distribution were investigated. The data measured show that the concentration of generated aerosol becomes higher both increasing the flow rate of the KCI solution injected in the first cylinder and increasing the concentration in the solution. The temperature of solution influences mainly the generation of smaller KCI particles （0,3-3 μm）. The amount of hot air used in the generation process increases the concentration of larger KC1 particles （〉3 μm） while cold air does not have the same effect. The aerosol generator is able to generate KC1 aerosol stably. This instrument can be used effectively for testing air filters for automotive.展开更多
Hypereutectic Al-40 wt.%Si alloys were fabricated by the combination of gas atomization and spark plasma sintering(SPS) technology. The effects of holding time(15-60 min) on phase composition, microstructure, density,...Hypereutectic Al-40 wt.%Si alloys were fabricated by the combination of gas atomization and spark plasma sintering(SPS) technology. The effects of holding time(15-60 min) on phase composition, microstructure, density,mechanical properties of Al-Si alloys were investigated by XRD, SEM, a hydrostatic balance, an automatic micro hardness tester and a universal tensile testing machine. The results showed that homogenous distribution of ultrafine primary Si and high density of alloys can be obtained at holding time of 30 min. Compared with primary Si(3.7 μm)fabricated by gas atomization, the average size increased from 5.17 to 7.72 μm with the increase of holding time during SPS process. Overall, the relative density, maximum tensile strength and Vickers hardness of 94.9%, 205 MPa and HV;196.86 were achieved at holding time of 30 min, respectively. In addition, all the diffraction peaks were corresponded to α-Al or β-Si and no other phase can be detected. Finally, the densification process of SPS was also discussed.展开更多
To study the abilities of Chlorella sorokiniana CS-01 on using CO2 from flue gases to produce biodiesel,the microaglae was cultured with different simulated flue gases containing 5%-15%(volume fraction) of CO2.The res...To study the abilities of Chlorella sorokiniana CS-01 on using CO2 from flue gases to produce biodiesel,the microaglae was cultured with different simulated flue gases containing 5%-15%(volume fraction) of CO2.The results show that strain CS-01 could grow at 15% CO2 and grow well under CO2 contents ranging from 5%-10%.The maximal biomass productivity and lipid productivity were obtained when aerating with 10% of CO2.The lipids content ranged from 28% to 43% of dry mass of biomass.The main fatty acid compositions of strain CS-01 were C14-C18(>72%) short-chain FAMEs(known as biodiesel feedstocks).Meanwhile,the biodiesel productivity was over 60%,suggesting that Chlorella sorokiniana CS-01 has a great potential for CO2 mitigation and biodiesel production.Furthermore,differential expression of three genes related to CO2 fixation and fatty acid synthesis were studied to further describe the effect of simulated flue gases on the growth and lipid accumulation of strain CS-01 at molecular level.展开更多
A refractory gold concentrate with 19% arsenic was treated by a mixed moderately thermophiles in an airlift bioreactor through an adaptation protocol. The moderately thermophiles could respond well to 20%(w/v) pulp de...A refractory gold concentrate with 19% arsenic was treated by a mixed moderately thermophiles in an airlift bioreactor through an adaptation protocol. The moderately thermophiles could respond well to 20%(w/v) pulp density with less than 10% loss of productivity, and resist arsenic up to 15 g/L. There were a lot of jarosite, arsenolite and sulfur, but not scorodite and ferric arsenate in the bioleached residue. Jarosite passivation and lower sulfur-oxidizing activity of the cells due to the toxicity of the high concentrations of soluble arsenic and iron ions at low p H value should mainly response for the incomplete extraction at high pulp density. The initial bacterial community did not change in nature except for new found P aeruginosa ANSC, but sulfur-oxidizing microorganisms have been dominant microorganisms after a long time of adaptation. Pseudomonas aeruginosa originating from the gold concentrate should be closely relative to the metabolism of the organic matters contained in the refractory gold concentrate.展开更多
文摘Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation activity were studied.Several different carbon materi-als were produced from them by oxida-tion in air(350℃,300 mL/min)fol-lowed by carbonization(1000℃ in Ar),and the effect of the cross-linked structure on their structure and sodium storage properties was investigated.The results showed that the two pitch fractions were obviously different after the air oxidation.The TS fraction with a low degree of condensation and abundant side chains had a stronger oxidation activity and thus introduced more cross-linked oxygen-containing functional groups C(O)―O which prevented carbon layer rearrangement during the carbonization.As a result,a disordered hard carbon with more defects was formed,which improved the electrochemical performance.Therefore,the carbon materials derived from TS(O-TS-1000)had an obvious disordered structure and a larger layer spacing,giving them better sodium storage perform-ance than those derived from the TI-PS fraction(O-TI-PS-1000).The specific capacity of O-TS-1000 was about 250 mAh/g at 20 mA/g,which was 1.67 times higher than that of O-TI-PS-1000(150 mAh/g).
基金Project(52022019)supported by the National Natural Science Foundation of China。
文摘The magnetization reduction of hematite using biomass waste can effectively utilize waste and reduce CO_(2) emission to achieve the goals of carbon peaking and carbon neutrality.The effects of temperatures on suspension magnetization roasting of hematite using biomass waste for evolved gases have been investigated using TG-FTIR,Py-GC/MS and gas composition analyzer.The mixture reduction process is divided into four stages.In the temperature range of 200-450℃ for mixture,the release of CO_(2),acids,and ketones is dominated in gases products.The yield and concentration of small molecules reducing gases increase when the temperature increases from 450 to 900℃.At 700℃,the volume concentrations of CO,H_(2) and CH_(4) peak at 8.91%,8.90% and 4.91%,respectively.During the suspension magnetization roasting process,an optimal iron concentrate with an iron grade of 70.86%,a recovery of 98.66% and a magnetic conversion of 45.70% is obtained at 700℃.Therefore,the magnetization reduction could react greatly in the temperature range of 600 to 700℃ owing to the suitable reducing gases.This study shows a detail gaseous evolution of roasting temperature and provides a new insight for studying the reduction process of hematite using biomass waste.
文摘This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternatives for liquid fuel and aviation industry is first discussed.Key insights encompass the evolutionary progression of biofuel production from first-generation to second-generation biofuels,with a focus on utilizing non-food sources like woody biomass for enhanced sustainability.Available data from the literature on techno-economic assessments of various SAF production pathways are analyzed including production costs,conversion efficiency,and scalability.Moreover,results of lifecycle assessments associated with different SAF production pathways are presented,providing essential insights for decision-making processes.The challenges of scaling up woody biomass-based SAF production are discussed based on the assessment results,and recommendations are proposed to steer stakeholders towards a greener and more sustainable trajectory for aviation operations.
基金Project(51275102)supported by the National Natural Science Foundation of ChinaProject(159070220011)supported by the Science and Technology Innovative Research Programs Foundation of Harbin city,ChinaProject(HEUCF110702)supported by the Fundamental Research Funds for the Central Universities of China
文摘To solve the problem of sealing between the barrel and the rubber ring of shell body during an launching process of aerodynamic extinguishing cannon, a rubber sealing model with bionic dimpled characteristics was established based on the theory of bionic dimpled drag reduction and the principle of rubber sealing. In condition that the bionic dimpled characteristic diameters were 1, 2, 3, 4, and 5 mm, respectively, by numerical simulation, the influence of the installing compression of the rubber sealing ring on its surface stress and deformation was analyzed, and sealing performance of the rubber ring with different diameters of bionic dimpled was studied. The results show that the deformation of rubber ring appears prominent nonlinear characteristics when compression is increased from 1.5 mm to 2.5 ram. When the compression is 2.5 mm, the equivalent compression stress on the sealing areas of both sides of the rubber seal is greater than the working pressure of aerodynamic extinguishing cannon, which could meet the sealing requirement and would not cause leakage. So the rubber sealing ring with bionic dimpled surface possesses a good sealing characteristic and has no negative effect on the sealing of shell body; When the compression is 2.5 mm, the larger equivalent stress on the edge of sealing ring and the more even stress distribution in the high pressure area are generated due to the smaller compressive stress on the bionic dimple areas, which lays a foundation for the drag reduction characteristics of the shell body＇s rubber ring with bionic dimpled surface.
文摘Producer gas through gasification of biomass can be used as an alternate fuel in rural areas due to high potential of biomass resources in India.Experiments were conducted to study the performance of a diesel engine(four stroke,single cylinder,5.25 kW) with respect to its thermal efficiency,specific fuel consumption and diesel substitution by use of diesel alone and producer gas-cum-diesel(dual fuel mode).Three types of biomass,i.e.wood chips,pigeon pea stalks and corn cobs were used for generation of producer gas.A producer gas system consisting of a downdraft gasifier,a cooling cum cleaning unit,a filtering unit and a gas air mixing device was designed,fabricated and used to power a 5.25 kW diesel engine on dual fuel mode.Performance of the engine was reported by keeping biomass moisture contents as 8%,12%,16%,and 21%,engine speed as 1 600 r/min and with variable engine loads.The average value of thermal efficiency on dual fuel mode was found slightly lower than that of diesel mode.The specific diesel consumption was found to be 60%-64% less in dual fuel mode than that in diesel mode for the same amount of energy output.The average diesel substitution of 74% was observed with wood chips followed by corn cobs(78%) and pigeon pea stalks(82%).Based on the performance studied,the producer gas may be used as a substitute or as supplementary fuel for diesel conservation,particularly for stationary engines in agricultural operations in the farm.
基金Project(2006BAJ04A)suppprted by the National Sci-Tech Support Plan,China
文摘Experiments were conducted to investigate the behavior of the sequential system of intensified zero-valent iron process(IZVI) and anaerobic filter and biological aerated filter(AF/BAF) reactors for advanced treatment of biologically pretreated coking wastewater. Particular attention was paid to the performance of the integrated system for the removal of chemical oxygen demand(COD), ammonia nitrogen(NH3-N) and total nitrogen(TN). The average removal efficiencies of COD, NH3-N and TN were 76.28%, 96.76% and 59.97%, with the average effluent mass concentrations of 56, 0.53 and 18.83 mg/L, respectively, reaching the first grade of the national discharge standard. Moreover, the results of gas chromatography/mass spectrum(GC/MS) and gel permeation chromatography(GPC) analysis demonstrated that the refractory organic compounds with high relative molecular mass were partly removed in IZVI process by the function of oxidation-reduction, flocculation and adsorption which could also enhance the biodegradability of the system effluent. The removal efficiencies of NH3-N and TN were achieved mainly in the subsequent AF/BAF reactors by nitrification and denitrification. Overall, the results obtained show that the application of IZVI in combination with AF/BAF is a promising technology for advanced treatment of biologically pretreated coking wastewater.
基金Projects(DEC-2011/01/B/ST8/07394,DEC-2011/01/D/ST8/07399)supported by the Polish National Centre for Science(NCN)
文摘Reburning was applied to Polish automatic coal-fired retort boiler (25 kW).The use of bio-syngas reduced NOx emissions from the boiler by over 25%,below the significant level of 200 mg/m3 .Reburning was carried out using an integrated system consisting of the boiler and a fixed-bed 60 kW (GazEla) gasification reactor.The process gas was continuously introduced above the coal burner of the boiler.The process parameters of the boiler and the gasifier were also measured and compared with the other units.Characteristic NOx emissions from automatic and manually operated boilers were also presented.
基金Project(2013020137)supported by the Natural Science Foundation of Liaoning Province,ChinaProject(2015-36)supported by Rural Energy Comprehensive Construction Foundation of the Ministry of Agriculture,China
文摘The gasification industries make use of biomass residue as feedstock to produce synthesis gas,but the gasification of this waste biomass generates tons of ash everyday.Performance properties and agglomeration behavior of corncob ash(CCA) collected from the gasification of corncobs in a pilot-scale gasification station were investigated by using some experimental methods.Based on the chemical composition results,the agglomeration tendency of CCA from combustion and gasification process was also analyzed.Chemical analysis shows that the fly ash is mainly composed of inorganic matters formed by K,Mg,Ca,Na,Fe,Al,S,etc.The agglomeration characteristics indicate that the slagging degree increases with the increase of ashing temperature,and the slagging tendency of these CCA samples from gasification or combustion is different with various slagging indices.All CCA samples from combustion or gasification can cause slagging/fouling problems in thermal conversion systems.The applications of CCA are closely related to its performances,and CCA has the potential to be used in various fields,for example,as a material for ceramic products and activated carbon,as an adsorbent,as a crude fertilizer,and as a structural material.
基金Projects(2008JT1013,2007JT3018,05SK3002) supported by the Key Program for Science and Technology in Hunan Province,ChinaProject(2007ZK2025) supported by the Key Program for Soft Science in Hunan Province,China
文摘The process of urbanization affects the urban warming.The change of urban warming was investigated by several urbanization factors in Changsha,China.The data of surface temperature(minimum,maximum and mean) of Changsha were analyzed to understand the possible effects of urbanization on the climate of this region owing to the population growth,built-up area expansion and energy consumption increases.The weights of these three factors were calculated by the analytical hierarchy process(AHP).Then,three weights were simulated with nonlinear method to obtain the urbanization development rate which was utilized to reveal the influence of the urbanization factors on the surface temperature.The result shows that there is a significant upward trend in the urban temperatures of Changsha.The temperature increase seems to be closely related to the rate of urbanization between 1993 and 2008,and there is an evidential increase trend of the influence on urban temperature by urbanization during 16 years.It is a quantifiable approach measuring the relationship between urbanization and urban eco-environment,and can be applied for the urban sustainability.
基金Project(2010EME006) supported by Open Fund of the Key Laboratory of Environmental Medicine Engineering of Ministry of Education of China Project(51008063) supported by the National Natural Science Foundation of China+1 种基金 Project(3203000601) supported by the Postdoctoral Key Research Program from Southeast University, China Project(2011BAJ03B05) supported by the National Science and Technology Pillar Program during the 12th Five-Year Plan Period of China
文摘Generation of polydisperse KCl aerosol with a new salt aerosol generator was investigated, Special attention was paid on particles with diameters between 3 and 10 μm. The main improvement consists of the different routes of KCl solution droplets. In traditional generators, the solution droplets travel through one cylinder; while in the case analyzed here, after spray atomization, the droplets travel through two cylinders in series. The first cylinder was fed with warm air and the second one with cold air. In such way, the complete evaporation of the water from the droplets can be ensured. The influencing factors of the generated aerosol size distribution were investigated. The data measured show that the concentration of generated aerosol becomes higher both increasing the flow rate of the KCI solution injected in the first cylinder and increasing the concentration in the solution. The temperature of solution influences mainly the generation of smaller KCI particles （0,3-3 μm）. The amount of hot air used in the generation process increases the concentration of larger KC1 particles （〉3 μm） while cold air does not have the same effect. The aerosol generator is able to generate KC1 aerosol stably. This instrument can be used effectively for testing air filters for automotive.
基金Project(18JS060) supported by the Shaanxi Key Laboratory of Nano-materials and Technology,ChinaProject(2018JQ5087) supported by Natural Science Basic Research Plan of Shaanxi Province,China。
文摘Hypereutectic Al-40 wt.%Si alloys were fabricated by the combination of gas atomization and spark plasma sintering(SPS) technology. The effects of holding time(15-60 min) on phase composition, microstructure, density,mechanical properties of Al-Si alloys were investigated by XRD, SEM, a hydrostatic balance, an automatic micro hardness tester and a universal tensile testing machine. The results showed that homogenous distribution of ultrafine primary Si and high density of alloys can be obtained at holding time of 30 min. Compared with primary Si(3.7 μm)fabricated by gas atomization, the average size increased from 5.17 to 7.72 μm with the increase of holding time during SPS process. Overall, the relative density, maximum tensile strength and Vickers hardness of 94.9%, 205 MPa and HV;196.86 were achieved at holding time of 30 min, respectively. In addition, all the diffraction peaks were corresponded to α-Al or β-Si and no other phase can be detected. Finally, the densification process of SPS was also discussed.
基金Project(50621063) supported by the National Natural Science Foundation for Distinguished Group of ChinaProjects(2010bsxt05,2010ssxt246) supported by the Innovation Foundation of Science and Technology of Central South University,China
文摘To study the abilities of Chlorella sorokiniana CS-01 on using CO2 from flue gases to produce biodiesel,the microaglae was cultured with different simulated flue gases containing 5%-15%(volume fraction) of CO2.The results show that strain CS-01 could grow at 15% CO2 and grow well under CO2 contents ranging from 5%-10%.The maximal biomass productivity and lipid productivity were obtained when aerating with 10% of CO2.The lipids content ranged from 28% to 43% of dry mass of biomass.The main fatty acid compositions of strain CS-01 were C14-C18(>72%) short-chain FAMEs(known as biodiesel feedstocks).Meanwhile,the biodiesel productivity was over 60%,suggesting that Chlorella sorokiniana CS-01 has a great potential for CO2 mitigation and biodiesel production.Furthermore,differential expression of three genes related to CO2 fixation and fatty acid synthesis were studied to further describe the effect of simulated flue gases on the growth and lipid accumulation of strain CS-01 at molecular level.
基金Project(2010CB630903)supported by the National Basic Research Program of ChinaProject(31200382)supported by the Chinese Science Foundation for Distinguished Group,China
文摘A refractory gold concentrate with 19% arsenic was treated by a mixed moderately thermophiles in an airlift bioreactor through an adaptation protocol. The moderately thermophiles could respond well to 20%(w/v) pulp density with less than 10% loss of productivity, and resist arsenic up to 15 g/L. There were a lot of jarosite, arsenolite and sulfur, but not scorodite and ferric arsenate in the bioleached residue. Jarosite passivation and lower sulfur-oxidizing activity of the cells due to the toxicity of the high concentrations of soluble arsenic and iron ions at low p H value should mainly response for the incomplete extraction at high pulp density. The initial bacterial community did not change in nature except for new found P aeruginosa ANSC, but sulfur-oxidizing microorganisms have been dominant microorganisms after a long time of adaptation. Pseudomonas aeruginosa originating from the gold concentrate should be closely relative to the metabolism of the organic matters contained in the refractory gold concentrate.
