The occurrence of blockages of trash intercepting net in nuclear power plant due to marine biofouling has become increasingly frequent,leading to significant changes in the mechanical state.This paper establishes a CF...The occurrence of blockages of trash intercepting net in nuclear power plant due to marine biofouling has become increasingly frequent,leading to significant changes in the mechanical state.This paper establishes a CFD(Computational Fluid Dynamics)model to simulate the hydrodynamic forces of trash intercepting net under the action of regular waves.The porous media model is used to calculate the hydrodynamic forces,and the maximum mooring load is also evaluated.The simplified calculation method considering the different curved shape based on the flat nets are proposed,and the influences of wave parameters,solidity,and curved shape are investigated.The results indicate that under the regular wave conditions,as the solidity increases,the phenomenon of secondary wave peaks becomes more pronounced.The horizontal wave force reduction coefficient follows a three-piecewise linear relationship with the non-dimensional deformation level of curved shape.The trash intercepting net exhibits more potent scattering effects on short-wave conditions,displaying significant non-linear characteristics.The deformation level of the trash intercepting net is a significant factor influencing the mooring load.展开更多
Oriented towards oceans governance,this article delves into the management of land-based pollutants such as plastics.Waste such as plastics is having a grave impact on environment.The micro-plastic accretion in the oc...Oriented towards oceans governance,this article delves into the management of land-based pollutants such as plastics.Waste such as plastics is having a grave impact on environment.The micro-plastic accretion in the oceans endangers sustainable development.However,the land-based waste disposal,both on the land and on the sea,has been a typical “tragedy of the commons” problems for the communities of the whole world.To save the oceans and to safeguard the sustainable development,we need more than ever to develop a better awareness of shared future for oceans.This article makes an assessment of the Shanghai practice in trash sorting.Through reviewing the trash segregation management procedures,it explores for an optimum solution through innovating a source-based trash management model.To jointly cope with the challenges for sustainable development,the article also intends to create a consensus on building a Trash Management Organization for Coastal Cities in response to the principle of building a community of shared future for mankind.展开更多
Micrometeorological and microplot experiments were conducted in the field of freshly harvested green cane in Queensland, Australia. Results showed that high ammonia loss of fertilizer N could occur under relatively dr...Micrometeorological and microplot experiments were conducted in the field of freshly harvested green cane in Queensland, Australia. Results showed that high ammonia loss of fertilizer N could occur under relatively dry conditions when urea or commercial product of mixture of urea and muriate of potash were applied to the surface of sugarcane trash. The moisture content in the trash and the pH of fertilizer were two important factors controlling the processes of urea hydrolysis and ammonia volatilization. Most of the N in the soil was transformed to the nitrate+ nitrite from after 70 days of fertilizer application. No significant leaching was found. Urea-free N fertilizers had higher N recoveries compared to urea-containing fertilizers. .展开更多
In the article, the motions of the magpies inside the fibrous material are studied in the presence of an elastic bonding force and the force of dry friction. It is assumed that the volatility of raw cotton in the form...In the article, the motions of the magpies inside the fibrous material are studied in the presence of an elastic bonding force and the force of dry friction. It is assumed that the volatility of raw cotton in the form of a ball hits the initial velocity about the grate, and after the impact the velocity of the center of mass of the volatility is zero. Until the moment of impact, the mote is located along the beam, which tilts to the horizon and has the same velocity with the center of the fly, and after the impact it moves along this ray. The case is considered when the coefficients of dynamic rigidity, adhesion strength and coefficient of friction depend on the temperature difference between the initial and the current, and it is assumed that these parameters decrease with increasing temperature difference. Accordingly, in the equation of motion of the mote, the sign of the speed of movement of the magpies is taken into account in the direction of the force of contact between it and the fibrous mass. Different stages of the motion of the speck along the ray are considered. On the basis of the equations obtained, the trajectories and the geometric locations of the points of location of the magpies located along the ray are established.展开更多
Turbulent flow through a trash rack of bars of rectangular and biconvex shapes is considered. A trash rack is composed of an array of bars fitted into a hydro-electric power station to prevent debris and fish to enter...Turbulent flow through a trash rack of bars of rectangular and biconvex shapes is considered. A trash rack is composed of an array of bars fitted into a hydro-electric power station to prevent debris and fish to enter the waterway towards the turbine. The work is directed towards modeling a large number of bars for which the flow turn out to have a periodic structure. It is here shown that this case can be simplified with the flow past a single bar together with periodic boundary conditions. Using this approach the head loss is derived for different angles of attack α and blockages P for two shapes of the rack, a rectangular bar and an aerodynamically shaped biconvex bar. It is found that overall loss of the biconvex bars is in general about 15% of the loss for the rectangular case for small angles of attack. For large angle of attack this difference diminishes. Of interest for the biconvex bars is also a local minimum in the head loss for angles approximately greater than 20°and for a blockage P around 0.35. This combination of parameters gives a low loss together with an efficient barrier for debris and fishes.展开更多
Environmental pollution has had substantial impacts on human life,and trash is one of the main sources of such pollution in most countries.Trash classi-fication from a collection of trash images can limit the overloadi...Environmental pollution has had substantial impacts on human life,and trash is one of the main sources of such pollution in most countries.Trash classi-fication from a collection of trash images can limit the overloading of garbage dis-posal systems and efficiently promote recycling activities;thus,development of such a classification system is topical and urgent.This paper proposed an effective trash classification system that relies on a classification module embedded in a hard-ware setup to classify trash in real time.An image dataset isfirst augmented to enhance the images before classifying them as either inorganic or organic trash.The deep learning–based ResNet-50 model,an improved version of the ResNet model,is used to classify trash from the dataset of trash images.The experimental results,which are tested both on the dataset and in real time,show that ResNet-50 had an average accuracy of 96%,higher than that of related models.Moreover,integrating the classification module into a Raspberry Pi computer,which con-trolled the trash bin slide so that garbage fell into the appropriate bin for inorganic or organic waste,created a complete trash classification system.This proves the efficiency and high applicability of the proposed system.展开更多
TRASH separation has become the talk of the town in China these days as the government unveils a list of 46 “pilot cities” which have been selected to build up a garbage sorting and processing system by 2020. Mandat...TRASH separation has become the talk of the town in China these days as the government unveils a list of 46 “pilot cities” which have been selected to build up a garbage sorting and processing system by 2020. Mandatory schemes on household garbage sorting have already emerged in metropolises like Shanghai in order to improve its recycling rates.展开更多
The Simultaneous Saccharification and Fermentation （SSF） of alkali-acid pretreated sugarcane trash to ethanol was optimized using commercial cellulase and Saccharomyces cerevisiae TISTR 5596 cells. Substrate concent...The Simultaneous Saccharification and Fermentation （SSF） of alkali-acid pretreated sugarcane trash to ethanol was optimized using commercial cellulase and Saccharomyces cerevisiae TISTR 5596 cells. Substrate concentration （12.5% w/v, 15% w/v, 17.5% w/v and 20% w/v）, enzyme loading （25 FPU/g Dry Substrate （DS）, 50 FPU/g DS and 75 FPU/g DS）, and temperature （30 ~C, 35 ~C and 40 ~C） were evaluated. The SSF optimal conditions for alkali-acid pretreated sugarcane trash were 20% w/v of substrate concentration, enzyme loading 50 FPU/g DS, temperature 35 ~C, initial pH 5.0 and yeast inoculum 107 cells/mL. Under the above optimal conditions, ethanol concentration was possible to reach in the range between 50.14 g/L and 55.08 g/L at 96 hrs and 144 hrs, respectively. This study could establish the effective utilization of sugarcane trash for bioethanol production using optimized fermentation parameters.展开更多
The present study was conducted for the optimization of pretreatment and enzymatic hydrolysis of lignocellulosic biomass （sugarcane trash）, which is a renewable resource for the production of bioethanol. The pretrea...The present study was conducted for the optimization of pretreatment and enzymatic hydrolysis of lignocellulosic biomass （sugarcane trash）, which is a renewable resource for the production of bioethanol. The pretreatment and enzymatic hydrolysis conditions including alkali （NaOH）/dilute acid （H2SO4）, substrate and chemical concentration for pretreatment, enzyme dosage, pH, temperature and substrate concentration for hydrolysis were varied and evaluated for sugar and ethanol production at the end. The optimum condition was accomplished using 15% w/v DS of 0-2 mm sugarcane trash in size of particle. It was pretreated with two steps of 2% w/v NaOH autoclaving followed by 2% w/v H2SO4 autoclaving with washing step after pretreatment. An enzymatic hydrolysis was then performed using 15% w/v DS pretreated substrate, hydrolyzed with cellulase 50 filter paper unit （FPU）/g DS at 50 ℃ and pH 5. After incubating at 160 r for 48 h, 117.16 g/L reducing sugar was obtained. The achieved sugar after enzymatic hydrolysis was finally fermented to ethanol by Saccharomyces cerevisiae TISTR 5596, with concentration of 48.17 g/L ethanol or yield 0.509 g/g reducing sugars which was equal to 99.81% of theoretical yield.展开更多
By making the use of the processes which includes separating trash and solid materials from the wastewater-ammonia stripping tower-UASB-biological oxidation pond, we have treated the wastewater which comes from the sw...By making the use of the processes which includes separating trash and solid materials from the wastewater-ammonia stripping tower-UASB-biological oxidation pond, we have treated the wastewater which comes from the swine factory. The treated wastewater can meet the primary standard of The People＇s Republic of China based on sewage discharge standards and the wastewater treatment project design contract （GBl8596-2001）, and the effluent will be used as irrigation-water. We introduce this project including the quality of influent and effluent and the flow scheme, the statement of every part, the investment and the effect, etc. The operation indicated that this process has many merits such as the stability in operation-effect and the convenience in management. So it will provide some help for the similar wastewater treatment.展开更多
Background:Cotton gin trash(CGT)is a lignocellulosic residue that can be used in the production of cellulosic ethanol.In a previous research,the sequential use of ultrasonication,liquid hot water,and ligninolytic enzy...Background:Cotton gin trash(CGT)is a lignocellulosic residue that can be used in the production of cellulosic ethanol.In a previous research,the sequential use of ultrasonication,liquid hot water,and ligninolytic enzymes was selected as pretreatment for the production of ethanol from CGT.However,an increment in the ethanol production is necessary.To accomplish that,this research evaluated the effect of pretreating CGT using alkaline ultrasonication before a liquid hot water and ligninolytic enzymes pretreatments for ethanol production.Three NaOH concentrations(5%,10%,and 15%)were employed for the alkaline ultrasonication.Additionally,this work is one of the first applications of Fourier transform infrared(FT-IR)spectrum and principal component analysis(PCA)as fast methodology to identify the differences in the biomass after different types of pretreatments.Results:The three concentrations employed for the alkaline ultrasonication pretreatment produced ethanol yields and cellulose conversions higher than the experiment without NaOH.Furthermore,15%NaOH concentration achieved twofold increment yield versus the treatment without NaOH.The FT-IR spectrum confirmed modifications in the CGT structure in the different pretreatments.PCA was helpful to determine differences between the pretreated and un-pretreated biomass and to evaluate how the CGT structure changed after each treatment.Conclusions:The combination of alkali ultrasonication hydrolysis,liquid hot water,and ligninolytic enzymes using 15%of NaOH improved 35%the ethanol yield compared with the original treatment.Additionally,we demonstrated the use of PCA to identify the modifications in the biomass structure after different types of pretreatments and conditions.展开更多
IF you thought empty plastic bottles were no more than an environmental hazard, think again. A South African factory is getting ready to transform these polluting irritants into glossy blankets and stuffing for pillow...IF you thought empty plastic bottles were no more than an environmental hazard, think again. A South African factory is getting ready to transform these polluting irritants into glossy blankets and stuffing for pillows, duvet, and other products. The Chinese-invested eco-friendly factory will also provide much-needed jobs in a country struggling with growing unemployment. On a chilly autumn day in Boksburg, a city some 30 km southeast of downtown Johannesburg, the blanket factory, located in the local industrial park, is warm and buzzing with the vibrations of indus- trial looms and knitting machines.展开更多
In recent years,with the concept of green development and the basic national policy of conserving resources and protecting the environment,China speeds up the construction of a resource-saving and environment-friendly...In recent years,with the concept of green development and the basic national policy of conserving resources and protecting the environment,China speeds up the construction of a resource-saving and environment-friendly society,and forms a new pattern of harmonious development of man and nature.展开更多
As China has expanded capacity to handle urban waste and divert trash from landfills,overcapacity in waste-to-energy plants has left some regions scrabbling for garbage.
基金financially supported by National Natural Science Foundation of China(Grant No.52201311)Fundamental Research Funds for the Central Universities.
文摘The occurrence of blockages of trash intercepting net in nuclear power plant due to marine biofouling has become increasingly frequent,leading to significant changes in the mechanical state.This paper establishes a CFD(Computational Fluid Dynamics)model to simulate the hydrodynamic forces of trash intercepting net under the action of regular waves.The porous media model is used to calculate the hydrodynamic forces,and the maximum mooring load is also evaluated.The simplified calculation method considering the different curved shape based on the flat nets are proposed,and the influences of wave parameters,solidity,and curved shape are investigated.The results indicate that under the regular wave conditions,as the solidity increases,the phenomenon of secondary wave peaks becomes more pronounced.The horizontal wave force reduction coefficient follows a three-piecewise linear relationship with the non-dimensional deformation level of curved shape.The trash intercepting net exhibits more potent scattering effects on short-wave conditions,displaying significant non-linear characteristics.The deformation level of the trash intercepting net is a significant factor influencing the mooring load.
基金supported by the National Social Science Fund of China (Grant Nos. 17BGJ046, 20VHQ004)
文摘Oriented towards oceans governance,this article delves into the management of land-based pollutants such as plastics.Waste such as plastics is having a grave impact on environment.The micro-plastic accretion in the oceans endangers sustainable development.However,the land-based waste disposal,both on the land and on the sea,has been a typical “tragedy of the commons” problems for the communities of the whole world.To save the oceans and to safeguard the sustainable development,we need more than ever to develop a better awareness of shared future for oceans.This article makes an assessment of the Shanghai practice in trash sorting.Through reviewing the trash segregation management procedures,it explores for an optimum solution through innovating a source-based trash management model.To jointly cope with the challenges for sustainable development,the article also intends to create a consensus on building a Trash Management Organization for Coastal Cities in response to the principle of building a community of shared future for mankind.
文摘Micrometeorological and microplot experiments were conducted in the field of freshly harvested green cane in Queensland, Australia. Results showed that high ammonia loss of fertilizer N could occur under relatively dry conditions when urea or commercial product of mixture of urea and muriate of potash were applied to the surface of sugarcane trash. The moisture content in the trash and the pH of fertilizer were two important factors controlling the processes of urea hydrolysis and ammonia volatilization. Most of the N in the soil was transformed to the nitrate+ nitrite from after 70 days of fertilizer application. No significant leaching was found. Urea-free N fertilizers had higher N recoveries compared to urea-containing fertilizers. .
文摘In the article, the motions of the magpies inside the fibrous material are studied in the presence of an elastic bonding force and the force of dry friction. It is assumed that the volatility of raw cotton in the form of a ball hits the initial velocity about the grate, and after the impact the velocity of the center of mass of the volatility is zero. Until the moment of impact, the mote is located along the beam, which tilts to the horizon and has the same velocity with the center of the fly, and after the impact it moves along this ray. The case is considered when the coefficients of dynamic rigidity, adhesion strength and coefficient of friction depend on the temperature difference between the initial and the current, and it is assumed that these parameters decrease with increasing temperature difference. Accordingly, in the equation of motion of the mote, the sign of the speed of movement of the magpies is taken into account in the direction of the force of contact between it and the fibrous mass. Different stages of the motion of the speck along the ray are considered. On the basis of the equations obtained, the trajectories and the geometric locations of the points of location of the magpies located along the ray are established.
基金The Swedish Agency of Energy and Stand Up for Energy
文摘Turbulent flow through a trash rack of bars of rectangular and biconvex shapes is considered. A trash rack is composed of an array of bars fitted into a hydro-electric power station to prevent debris and fish to enter the waterway towards the turbine. The work is directed towards modeling a large number of bars for which the flow turn out to have a periodic structure. It is here shown that this case can be simplified with the flow past a single bar together with periodic boundary conditions. Using this approach the head loss is derived for different angles of attack α and blockages P for two shapes of the rack, a rectangular bar and an aerodynamically shaped biconvex bar. It is found that overall loss of the biconvex bars is in general about 15% of the loss for the rectangular case for small angles of attack. For large angle of attack this difference diminishes. Of interest for the biconvex bars is also a local minimum in the head loss for angles approximately greater than 20°and for a blockage P around 0.35. This combination of parameters gives a low loss together with an efficient barrier for debris and fishes.
文摘Environmental pollution has had substantial impacts on human life,and trash is one of the main sources of such pollution in most countries.Trash classi-fication from a collection of trash images can limit the overloading of garbage dis-posal systems and efficiently promote recycling activities;thus,development of such a classification system is topical and urgent.This paper proposed an effective trash classification system that relies on a classification module embedded in a hard-ware setup to classify trash in real time.An image dataset isfirst augmented to enhance the images before classifying them as either inorganic or organic trash.The deep learning–based ResNet-50 model,an improved version of the ResNet model,is used to classify trash from the dataset of trash images.The experimental results,which are tested both on the dataset and in real time,show that ResNet-50 had an average accuracy of 96%,higher than that of related models.Moreover,integrating the classification module into a Raspberry Pi computer,which con-trolled the trash bin slide so that garbage fell into the appropriate bin for inorganic or organic waste,created a complete trash classification system.This proves the efficiency and high applicability of the proposed system.
文摘TRASH separation has become the talk of the town in China these days as the government unveils a list of 46 “pilot cities” which have been selected to build up a garbage sorting and processing system by 2020. Mandatory schemes on household garbage sorting have already emerged in metropolises like Shanghai in order to improve its recycling rates.
文摘The Simultaneous Saccharification and Fermentation （SSF） of alkali-acid pretreated sugarcane trash to ethanol was optimized using commercial cellulase and Saccharomyces cerevisiae TISTR 5596 cells. Substrate concentration （12.5% w/v, 15% w/v, 17.5% w/v and 20% w/v）, enzyme loading （25 FPU/g Dry Substrate （DS）, 50 FPU/g DS and 75 FPU/g DS）, and temperature （30 ~C, 35 ~C and 40 ~C） were evaluated. The SSF optimal conditions for alkali-acid pretreated sugarcane trash were 20% w/v of substrate concentration, enzyme loading 50 FPU/g DS, temperature 35 ~C, initial pH 5.0 and yeast inoculum 107 cells/mL. Under the above optimal conditions, ethanol concentration was possible to reach in the range between 50.14 g/L and 55.08 g/L at 96 hrs and 144 hrs, respectively. This study could establish the effective utilization of sugarcane trash for bioethanol production using optimized fermentation parameters.
文摘The present study was conducted for the optimization of pretreatment and enzymatic hydrolysis of lignocellulosic biomass （sugarcane trash）, which is a renewable resource for the production of bioethanol. The pretreatment and enzymatic hydrolysis conditions including alkali （NaOH）/dilute acid （H2SO4）, substrate and chemical concentration for pretreatment, enzyme dosage, pH, temperature and substrate concentration for hydrolysis were varied and evaluated for sugar and ethanol production at the end. The optimum condition was accomplished using 15% w/v DS of 0-2 mm sugarcane trash in size of particle. It was pretreated with two steps of 2% w/v NaOH autoclaving followed by 2% w/v H2SO4 autoclaving with washing step after pretreatment. An enzymatic hydrolysis was then performed using 15% w/v DS pretreated substrate, hydrolyzed with cellulase 50 filter paper unit （FPU）/g DS at 50 ℃ and pH 5. After incubating at 160 r for 48 h, 117.16 g/L reducing sugar was obtained. The achieved sugar after enzymatic hydrolysis was finally fermented to ethanol by Saccharomyces cerevisiae TISTR 5596, with concentration of 48.17 g/L ethanol or yield 0.509 g/g reducing sugars which was equal to 99.81% of theoretical yield.
文摘By making the use of the processes which includes separating trash and solid materials from the wastewater-ammonia stripping tower-UASB-biological oxidation pond, we have treated the wastewater which comes from the swine factory. The treated wastewater can meet the primary standard of The People＇s Republic of China based on sewage discharge standards and the wastewater treatment project design contract （GBl8596-2001）, and the effluent will be used as irrigation-water. We introduce this project including the quality of influent and effluent and the flow scheme, the statement of every part, the investment and the effect, etc. The operation indicated that this process has many merits such as the stability in operation-effect and the convenience in management. So it will provide some help for the similar wastewater treatment.
文摘Background:Cotton gin trash(CGT)is a lignocellulosic residue that can be used in the production of cellulosic ethanol.In a previous research,the sequential use of ultrasonication,liquid hot water,and ligninolytic enzymes was selected as pretreatment for the production of ethanol from CGT.However,an increment in the ethanol production is necessary.To accomplish that,this research evaluated the effect of pretreating CGT using alkaline ultrasonication before a liquid hot water and ligninolytic enzymes pretreatments for ethanol production.Three NaOH concentrations(5%,10%,and 15%)were employed for the alkaline ultrasonication.Additionally,this work is one of the first applications of Fourier transform infrared(FT-IR)spectrum and principal component analysis(PCA)as fast methodology to identify the differences in the biomass after different types of pretreatments.Results:The three concentrations employed for the alkaline ultrasonication pretreatment produced ethanol yields and cellulose conversions higher than the experiment without NaOH.Furthermore,15%NaOH concentration achieved twofold increment yield versus the treatment without NaOH.The FT-IR spectrum confirmed modifications in the CGT structure in the different pretreatments.PCA was helpful to determine differences between the pretreated and un-pretreated biomass and to evaluate how the CGT structure changed after each treatment.Conclusions:The combination of alkali ultrasonication hydrolysis,liquid hot water,and ligninolytic enzymes using 15%of NaOH improved 35%the ethanol yield compared with the original treatment.Additionally,we demonstrated the use of PCA to identify the modifications in the biomass structure after different types of pretreatments and conditions.
文摘IF you thought empty plastic bottles were no more than an environmental hazard, think again. A South African factory is getting ready to transform these polluting irritants into glossy blankets and stuffing for pillows, duvet, and other products. The Chinese-invested eco-friendly factory will also provide much-needed jobs in a country struggling with growing unemployment. On a chilly autumn day in Boksburg, a city some 30 km southeast of downtown Johannesburg, the blanket factory, located in the local industrial park, is warm and buzzing with the vibrations of indus- trial looms and knitting machines.
文摘In recent years,with the concept of green development and the basic national policy of conserving resources and protecting the environment,China speeds up the construction of a resource-saving and environment-friendly society,and forms a new pattern of harmonious development of man and nature.
文摘As China has expanded capacity to handle urban waste and divert trash from landfills,overcapacity in waste-to-energy plants has left some regions scrabbling for garbage.
