Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in neurons.As one of the major intracellular...Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in neurons.As one of the major intracellular degradation pathways,the autophagy-lysosome pathway plays an important role in eliminating these proteins.Accumulating evidence has shown that upregulation of the autophagy-lysosome pathway may contribute to the clearance ofα-synuclein aggregates and protect against degeneration of dopaminergic neurons in Parkinson’s disease.Moreover,multiple genes associated with the pathogenesis of Parkinson’s disease are intimately linked to alterations in the autophagy-lysosome pathway.Thus,this pathway appears to be a promising therapeutic target for treatment of Parkinson’s disease.In this review,we briefly introduce the machinery of autophagy.Then,we provide a description of the effects of Parkinson’s disease–related genes on the autophagy-lysosome pathway.Finally,we highlight the potential chemical and genetic therapeutic strategies targeting the autophagy–lysosome pathway and their applications in Parkinson’s disease.展开更多
Chinese fir(Cunninghamia lanceolata(Lamb.)Hook),a fast-growing and economically important timber tree species in China,is widely used in construction,furniture,and paper manufacture but has a long breeding cycle.Chemi...Chinese fir(Cunninghamia lanceolata(Lamb.)Hook),a fast-growing and economically important timber tree species in China,is widely used in construction,furniture,and paper manufacture but has a long breeding cycle.Chemical mutagens,such as ethyl methane sulfonate(EMS)and sodium azide(SA),are widely used in crops such as rice,wheat,cotton,soybean and sugarcane but their utility for tree breeding is unknown.In this study we examined the effects of EMS and S A on Chinese fir seed germination and growth.Chinese fir seeds were treated with the two chemical mutagens;were planted in Jiangle County,Fujian Province,China;and their heights were measured from 2011 to2017.The concentrations and durations of treatment with the two chemical mutagens were significantly associated with the Chinese fir seedling and mortality rates,as well as with the heights of trees from the seedling stage to 3 years old.We also generated 127 mutants with abnormal branches and reproductive growth.We report here the effects of two chemical mutagens on Chinese fir breeding;our data will contribute to knowledge of the utility of EMS and SA in forestry.展开更多
In view of the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them, there is a need to investiga...In view of the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them, there is a need to investigate modern trends in ground improvement techniques in order to determine their reliability. This study is thus aimed at using the reliability based approach to analyze the use of polyvinyl alcohol (PVA) in combination with 1,2,3,4 Butane-tetracarboxylic acid (BTCA) for ground improvement. This study is necessary given the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them. Simplex lattice design was employed to build the design of experiment before experimental investigations were carried out on the PVA-BTCA treated soft soils. Reliability indices were computed on the basis of the 28<sup>th</sup> day unconfined compressive strength (UCS) of the treated soil. Reliability index models were developed using the Scheffe’s technique and optimized using excel solver. From analysis of results, reliability model developed proved adequate at 5% level of significance. PVA-BTCA combination provided a potential reliability or probability of success of 99.936% at components combination of: 98.4256% for soil, 1.2352% for PVA, 0.3392% for BTCA and 15.9934% for water. It was therefore recommended that financial implications of using PVA-BTCA for stabilization be compared to those of conventional methods, in order to compare their performance-cost ratio.展开更多
Due to their low cost,environmental friendliness and high energy density,the lithium-sulfur batteries(LSB)have been regarded as a promising alternative for the next generation of rechargeable battery systems.However,t...Due to their low cost,environmental friendliness and high energy density,the lithium-sulfur batteries(LSB)have been regarded as a promising alternative for the next generation of rechargeable battery systems.However,the practical application of LSB is seriously hampered by its short cycle life and high self-charge owing to the apparent shuttle effect of soluble lithium polysulfides.Using MgSO_(4)@MgO composite as both template and dopant,template-guided S-doped mesoporous graphene(SMG)is prepared via the fluidized-bed chemical vapor deposition method.As the polypropylene(PP)modifier,SMG with high specific surface area,abundant mesoporous structures and moderate S doping content offers a wealth of physical and chemical adsorptive sites and reduced interfacial contact resistance,thereby restraining the serious shuttle effects of lithium polysulfides.Consequently,the LSB configured with mesoporous graphene(MG)as S host material and SMG as a separator modifier exhibits an enhanced electrochemical performance with a high average capacity of 955.64 mA h g^(-1) at 1C and a small capacity decay rate of 0.109%per cycle.Additionally,the density functional theory(DFT)calculation models have been rationally constructed and demonstrated that the doped S atoms in SMG possess higher binding energy to lithium polysulfides than that in MG,indicating that the SMG/PP separator can effectively capture soluble lithium polysulfides via chemical binding forces.This work would provide valuable insight into developing a versatile carbon-based separator modifier for LSB.展开更多
One of the most effective methods for sand control is the chemical consolidation of sandstone structures.In this paper,the impacts of crude oil and brine in the static state and the impact of the flow rates of the flu...One of the most effective methods for sand control is the chemical consolidation of sandstone structures.In this paper,the impacts of crude oil and brine in the static state and the impact of the flow rates of the fluids in the dynamic state have been assessed at the reservoir conditions.The analyses in this research were Young’s modulus,compressive strength,porosity,and permeability which were done on core samples after and before fluid contact.Samples made with two different resins showed good resistance to crude oil in both states.No considerable change was seen in the analyses even at high crude oil injection rates in the dynamic state.Conversely,brine caused a noticeable change in the analyses in both states.In the presence of brine at the static state,Young’s modulus and compressive strength respectively decreased by 37.5%and 34.5%for epoxy cores,whereas these parameters respectively reduced by 30%and 41%for furan cores.In brine presence at the dynamic state,compressive strength reduction was 10.28 MPa for furan and 6.28 MPa for epoxy samples and their compressive strength reached 16.75 MPa and 26.54 MPa respectively which are higher than the critical point to be known as weak sandstone core.Moreover,Young’s modulus decrease values for furan and epoxy samples were respectively 0.37 GPa and 0.44 GPa.Therefore,brine had a more destructive effect on the mechanical characteristics of samples in the static state than the dynamic one for two resins.In addition,brine injection increased permeability by about 13.6%for furan and 34.8%for epoxy.Also,porosity raised by about 21.8%for furan,and 19%for epoxy by brine injection.The results showed that the chemical sand consolidation weakens in the face of brine production along with crude oil which can lead to increasing cost of oil production and treating wellbore again.展开更多
Three compounds were obtained from the mycelia of an endophytic fungus Gliocladium sp. (designated as strain F) of Taxus chinensis (Pilg.) Rehd. growing in Fujian Province, China. Their structures were determined on t...Three compounds were obtained from the mycelia of an endophytic fungus Gliocladium sp. (designated as strain F) of Taxus chinensis (Pilg.) Rehd. growing in Fujian Province, China. Their structures were determined on the basis of spectral analysis. (20S,22S)-4a-homo-22-hydroxy-4-oxaergosta-7,24(28)-dien-3-one was a novel compound. 4,8,12,16-tetramethyl-1,5,9,13-tetraoxacyclohexadecane-2,6,10,14-tetraone was firstly isolated from the genus ofGliocladium and 6,9-epoxyergosta-7,22-dien-3-ol was firstly obtained from the strain F.展开更多
The structural parameters, chemical bonding and elastic properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were investigated by using density-functional theory (DFT) within generalized ...The structural parameters, chemical bonding and elastic properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were investigated by using density-functional theory (DFT) within generalized gradient approximation (GGA). The GGA calculated structural parameters are in agreement with the experimental results. Population analysis suggests that the chemical bonding in YZnAsO and LaZnAsO can be classified as a mixture of ionic and covalent characteristic. Single-crystal elastic constants were calculated and the polycrystalline elastic modules were estimated according to Voigt, Reuss and Hill's approximations (VRH). The result shows that both YZnAsO and LaZnAsO are relatively soft materials exhibiting ductile behavior. The calculated polycrystalline elastic anisotropy result shows that LaZnAsO is more anisotropy in compressibility and YZnAsO is more anisotropy in shear.展开更多
Owing to their low cost,high energy densities,and superior performance compared with that of Li-ion batteries,Li–S batteries have been recognized as very promising next-generation batteries.However,the commercializat...Owing to their low cost,high energy densities,and superior performance compared with that of Li-ion batteries,Li–S batteries have been recognized as very promising next-generation batteries.However,the commercialization of Li–S batteries has been hindered by the insulation of sulfur,significant volume expansion,shuttling of dissolved lithium polysulfides(Li PSs),and more importantly,sluggish conversion of polysulfide intermediates.To overcome these problems,a state-of-the-art strategy is to use sulfur host materials that feature chemical adsorption and electrocatalytic capabilities for Li PS species.In this review,we comprehensively illustrate the latest progress on the rational design and controllable fabrication of materials with chemical adsorbing and binding capabilities for Li PSs and electrocatalytic activities that allow them to accelerate the conversion of Li PSs for Li–S batteries.Moreover,the current essential challenges encountered when designing these materials are summarized,and possible solutions are proposed.We hope that this review could provide some strategies and theoretical guidance for developing novel chemical anchoring and electrocatalytic materials for high-performance Li–S batteries.展开更多
The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen(N)levels are important indicators of the effect...The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen(N)levels are important indicators of the effect of reclaimed water irrigation on environment.This study evaluated soil physicochemical properties and microbial community structure in soils irrigated with reclaimed water and receiving varied amounts of N fertilizer.The results indicated that the reclaimed water irrigation increased soil electrical conductivity(EC)and soil water content(SWC).The N treatment has highly significant effect on the ACE,Chao,Shannon(H)and Coverage indices.Based on a 16S ribosomal RNA(16S rRNA)sequence analysis,the Proteobacteria,Gemmatimonadetes and Bacteroidetes were more abundant in soil irrigated with reclaimed water than in soil irrigated with clean water.Stronger clustering of microbial communities using either clean or reclaimed water for irrigation indicated that the type of irrigation water may have a greater influence on the structure of soil microbial community than N fertilizer treatment.Based on a canonical correspondence analysis(CCA)between the species of soil microbes and the chemical properties of the soil,which indicated that nitrate N(NO3-–-N)and total phosphorus(TP)had significant impact on abundance of Verrucomicrobia and Gemmatimonadetes,meanwhile the p H and organic matter(OM)had impact on abundance of Firmicutes and Actinobacteria significantly.It was beneficial to the improvement of soil bacterial activity and fertility under 120 mg kg^-1 N with reclaimed water irrigation.展开更多
The emission of the traditional energy chemical industry accounts for 20% of the total manmade VOC emission in China, of which coal chemical and petrochemical plants are one of the most important VOC emission sources....The emission of the traditional energy chemical industry accounts for 20% of the total manmade VOC emission in China, of which coal chemical and petrochemical plants are one of the most important VOC emission sources. VOC emission sources mainly include the leakage of oil refinery units and equipment, pipes and valves, respiration and leakage of various types of storage tanks, effusion of oils during loading and unloading, effusion of sewage treatment systems, all kinds of process tail gas, etc. In this paper, the current management status of VOC emission in China’s coal chemical industry and petrochemical industry are analyzed, which divides VOC management into intentional and fugitive emission. The Leak Detection and Repair (LDAR) management method and technology for equipment, pipes and valves implemented in the United States are studied to propose self-inspection management methods and measures for VOC emissions in the energy chemical industry, providing strategies and recommendations for energy conservation, emission reduction and cleaner production in the traditional energy chemical industry.展开更多
In the etiology of hepatocellular carcinoma (HCC), in addition to hepatitis B virus and hepatitis C virus infections, chemical carcinogens also play important roles. For example, aflatoxin B 1 (AFB 1 ) epoxide reacts ...In the etiology of hepatocellular carcinoma (HCC), in addition to hepatitis B virus and hepatitis C virus infections, chemical carcinogens also play important roles. For example, aflatoxin B 1 (AFB 1 ) epoxide reacts with guanine in DNA and can lead to genetic changes. In HCC, the tumor suppressor gene p53 codon 249 mutation is associated with AFB 1 exposure and mutations in the K -ras oncogene are related to vinyl chloride exposure. Numerous genetic alterations accumulate during the process of hepatocarcinogenesis. Chemical carcinogen DNA-adduct formation is the basis for these genetic changes and also a molecular marker which reflects exposure level and biological effects. Metabolism of chemical carcinogens, including their activation and detoxification, also plays a key role in chemical hepatocarcinogenesis. Cytochrome p450 enzymes, N -acetyltransferases and glutathione S -transferases are involved in activating and detoxifying chemical carcinogens. These enzymes are polymorphic and genetic variation influences biological response to chemical carcinogens. This genetic variation has been postulated to influence the variability in risk for HCC observed both within and across populations. Ongoing studies seek to fully understand the mechanisms by which genetic variation in response to chemical carcinogens impacts on HCC risk.展开更多
The hydrodynamic research about the droplet condensing of the multi phase liquid state on the surface of the coal glass and water discusses the deepening process of convex shape curve and the formation of S shape, and...The hydrodynamic research about the droplet condensing of the multi phase liquid state on the surface of the coal glass and water discusses the deepening process of convex shape curve and the formation of S shape, and puts emphasis on describing the diagram formation method of the later. In the induction period the active diagram of the micro droplet is decided by pH value forming as convex shape diagram or S shape diagram. When pH value is above 4.0, the damage of convex shape diagram cannot be recovered, in that case produce S shape activity diagram. When pH value is equal to or above 12.0, the hard surface with alkali liquid state loses adhesion, so that the micro droplet condensing of the multi phase liquid state stops completely. The research result shows that the water cleaning conditions of getting rid of the oil micro droplets can be decided by the pH value.展开更多
Athetis lepigone Moschler is a new kind of insect pest occurring in summer corn production areas. By investigation, it was found especially serious in straw returning fields. In this paper, its damage status was inves...Athetis lepigone Moschler is a new kind of insect pest occurring in summer corn production areas. By investigation, it was found especially serious in straw returning fields. In this paper, its damage status was investigated in straw returning and chemical controlled fields, respectively. The results showed that the rate of damaged plants was 82% and the maximum pest number per 100 plants was 88 heads in the straw returning fields without chemical control. The application of herbicides and pesticides had no significant effects on occurrence quantity and damage rate, but the pest number per 100 plants decreased a little compared to the fields without chemical control. In the surer er maize fields without straw returning, the application of herbicides and pesticides could significantly decrease the damage of Athetis lepigone, the rate of damaged plants was 20%, and the pest number per 100 plants was 6.展开更多
基金supported by the National Natural Science Foundation of China,No.82101340(to FJ).
文摘Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in neurons.As one of the major intracellular degradation pathways,the autophagy-lysosome pathway plays an important role in eliminating these proteins.Accumulating evidence has shown that upregulation of the autophagy-lysosome pathway may contribute to the clearance ofα-synuclein aggregates and protect against degeneration of dopaminergic neurons in Parkinson’s disease.Moreover,multiple genes associated with the pathogenesis of Parkinson’s disease are intimately linked to alterations in the autophagy-lysosome pathway.Thus,this pathway appears to be a promising therapeutic target for treatment of Parkinson’s disease.In this review,we briefly introduce the machinery of autophagy.Then,we provide a description of the effects of Parkinson’s disease–related genes on the autophagy-lysosome pathway.Finally,we highlight the potential chemical and genetic therapeutic strategies targeting the autophagy–lysosome pathway and their applications in Parkinson’s disease.
基金supported by grants from the Guangdong Provincial Science and Technology Plan Project(2016B020201002)the Science and Technology Research Project of Beijing Forestry University(2018WS01)+2 种基金the Research and Development Project of Beijing Forestry University(2016BLPX13)the National Natural Science Foundation of China(31700581)the Key Project of the National Forestry Bureau(2012–06)。
文摘Chinese fir(Cunninghamia lanceolata(Lamb.)Hook),a fast-growing and economically important timber tree species in China,is widely used in construction,furniture,and paper manufacture but has a long breeding cycle.Chemical mutagens,such as ethyl methane sulfonate(EMS)and sodium azide(SA),are widely used in crops such as rice,wheat,cotton,soybean and sugarcane but their utility for tree breeding is unknown.In this study we examined the effects of EMS and S A on Chinese fir seed germination and growth.Chinese fir seeds were treated with the two chemical mutagens;were planted in Jiangle County,Fujian Province,China;and their heights were measured from 2011 to2017.The concentrations and durations of treatment with the two chemical mutagens were significantly associated with the Chinese fir seedling and mortality rates,as well as with the heights of trees from the seedling stage to 3 years old.We also generated 127 mutants with abnormal branches and reproductive growth.We report here the effects of two chemical mutagens on Chinese fir breeding;our data will contribute to knowledge of the utility of EMS and SA in forestry.
文摘In view of the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them, there is a need to investigate modern trends in ground improvement techniques in order to determine their reliability. This study is thus aimed at using the reliability based approach to analyze the use of polyvinyl alcohol (PVA) in combination with 1,2,3,4 Butane-tetracarboxylic acid (BTCA) for ground improvement. This study is necessary given the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them. Simplex lattice design was employed to build the design of experiment before experimental investigations were carried out on the PVA-BTCA treated soft soils. Reliability indices were computed on the basis of the 28<sup>th</sup> day unconfined compressive strength (UCS) of the treated soil. Reliability index models were developed using the Scheffe’s technique and optimized using excel solver. From analysis of results, reliability model developed proved adequate at 5% level of significance. PVA-BTCA combination provided a potential reliability or probability of success of 99.936% at components combination of: 98.4256% for soil, 1.2352% for PVA, 0.3392% for BTCA and 15.9934% for water. It was therefore recommended that financial implications of using PVA-BTCA for stabilization be compared to those of conventional methods, in order to compare their performance-cost ratio.
基金supported by the Science Foundation of China University of Petroleum,Beijing(No.ZX20230047)Open Research Fund of State Key Laboratory of Coking Coal Exploitation and Comprehensive Utilization,China Pingmei Shenma Group(No.41040220201308).
文摘Due to their low cost,environmental friendliness and high energy density,the lithium-sulfur batteries(LSB)have been regarded as a promising alternative for the next generation of rechargeable battery systems.However,the practical application of LSB is seriously hampered by its short cycle life and high self-charge owing to the apparent shuttle effect of soluble lithium polysulfides.Using MgSO_(4)@MgO composite as both template and dopant,template-guided S-doped mesoporous graphene(SMG)is prepared via the fluidized-bed chemical vapor deposition method.As the polypropylene(PP)modifier,SMG with high specific surface area,abundant mesoporous structures and moderate S doping content offers a wealth of physical and chemical adsorptive sites and reduced interfacial contact resistance,thereby restraining the serious shuttle effects of lithium polysulfides.Consequently,the LSB configured with mesoporous graphene(MG)as S host material and SMG as a separator modifier exhibits an enhanced electrochemical performance with a high average capacity of 955.64 mA h g^(-1) at 1C and a small capacity decay rate of 0.109%per cycle.Additionally,the density functional theory(DFT)calculation models have been rationally constructed and demonstrated that the doped S atoms in SMG possess higher binding energy to lithium polysulfides than that in MG,indicating that the SMG/PP separator can effectively capture soluble lithium polysulfides via chemical binding forces.This work would provide valuable insight into developing a versatile carbon-based separator modifier for LSB.
文摘One of the most effective methods for sand control is the chemical consolidation of sandstone structures.In this paper,the impacts of crude oil and brine in the static state and the impact of the flow rates of the fluids in the dynamic state have been assessed at the reservoir conditions.The analyses in this research were Young’s modulus,compressive strength,porosity,and permeability which were done on core samples after and before fluid contact.Samples made with two different resins showed good resistance to crude oil in both states.No considerable change was seen in the analyses even at high crude oil injection rates in the dynamic state.Conversely,brine caused a noticeable change in the analyses in both states.In the presence of brine at the static state,Young’s modulus and compressive strength respectively decreased by 37.5%and 34.5%for epoxy cores,whereas these parameters respectively reduced by 30%and 41%for furan cores.In brine presence at the dynamic state,compressive strength reduction was 10.28 MPa for furan and 6.28 MPa for epoxy samples and their compressive strength reached 16.75 MPa and 26.54 MPa respectively which are higher than the critical point to be known as weak sandstone core.Moreover,Young’s modulus decrease values for furan and epoxy samples were respectively 0.37 GPa and 0.44 GPa.Therefore,brine had a more destructive effect on the mechanical characteristics of samples in the static state than the dynamic one for two resins.In addition,brine injection increased permeability by about 13.6%for furan and 34.8%for epoxy.Also,porosity raised by about 21.8%for furan,and 19%for epoxy by brine injection.The results showed that the chemical sand consolidation weakens in the face of brine production along with crude oil which can lead to increasing cost of oil production and treating wellbore again.
文摘Three compounds were obtained from the mycelia of an endophytic fungus Gliocladium sp. (designated as strain F) of Taxus chinensis (Pilg.) Rehd. growing in Fujian Province, China. Their structures were determined on the basis of spectral analysis. (20S,22S)-4a-homo-22-hydroxy-4-oxaergosta-7,24(28)-dien-3-one was a novel compound. 4,8,12,16-tetramethyl-1,5,9,13-tetraoxacyclohexadecane-2,6,10,14-tetraone was firstly isolated from the genus ofGliocladium and 6,9-epoxyergosta-7,22-dien-3-ol was firstly obtained from the strain F.
基金Project(50474051)supported by the National Natural Science Foundation of China
文摘The structural parameters, chemical bonding and elastic properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were investigated by using density-functional theory (DFT) within generalized gradient approximation (GGA). The GGA calculated structural parameters are in agreement with the experimental results. Population analysis suggests that the chemical bonding in YZnAsO and LaZnAsO can be classified as a mixture of ionic and covalent characteristic. Single-crystal elastic constants were calculated and the polycrystalline elastic modules were estimated according to Voigt, Reuss and Hill's approximations (VRH). The result shows that both YZnAsO and LaZnAsO are relatively soft materials exhibiting ductile behavior. The calculated polycrystalline elastic anisotropy result shows that LaZnAsO is more anisotropy in compressibility and YZnAsO is more anisotropy in shear.
基金supported by the National Natural Science Foundation of China(No.51403094)Program of Liaoning Education Department of China(No.LJ2017FBL002)Australian Research Council through the Discovery Early Career Researcher Award(DECRA,No.DE170100871)Program.
文摘Owing to their low cost,high energy densities,and superior performance compared with that of Li-ion batteries,Li–S batteries have been recognized as very promising next-generation batteries.However,the commercialization of Li–S batteries has been hindered by the insulation of sulfur,significant volume expansion,shuttling of dissolved lithium polysulfides(Li PSs),and more importantly,sluggish conversion of polysulfide intermediates.To overcome these problems,a state-of-the-art strategy is to use sulfur host materials that feature chemical adsorption and electrocatalytic capabilities for Li PS species.In this review,we comprehensively illustrate the latest progress on the rational design and controllable fabrication of materials with chemical adsorbing and binding capabilities for Li PSs and electrocatalytic activities that allow them to accelerate the conversion of Li PSs for Li–S batteries.Moreover,the current essential challenges encountered when designing these materials are summarized,and possible solutions are proposed.We hope that this review could provide some strategies and theoretical guidance for developing novel chemical anchoring and electrocatalytic materials for high-performance Li–S batteries.
基金the financial support for this research from the National High-Tech R&D Program of China (2012AA101404)the National Natural Science Foundation of China (51209208, 51479201)
文摘The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen(N)levels are important indicators of the effect of reclaimed water irrigation on environment.This study evaluated soil physicochemical properties and microbial community structure in soils irrigated with reclaimed water and receiving varied amounts of N fertilizer.The results indicated that the reclaimed water irrigation increased soil electrical conductivity(EC)and soil water content(SWC).The N treatment has highly significant effect on the ACE,Chao,Shannon(H)and Coverage indices.Based on a 16S ribosomal RNA(16S rRNA)sequence analysis,the Proteobacteria,Gemmatimonadetes and Bacteroidetes were more abundant in soil irrigated with reclaimed water than in soil irrigated with clean water.Stronger clustering of microbial communities using either clean or reclaimed water for irrigation indicated that the type of irrigation water may have a greater influence on the structure of soil microbial community than N fertilizer treatment.Based on a canonical correspondence analysis(CCA)between the species of soil microbes and the chemical properties of the soil,which indicated that nitrate N(NO3-–-N)and total phosphorus(TP)had significant impact on abundance of Verrucomicrobia and Gemmatimonadetes,meanwhile the p H and organic matter(OM)had impact on abundance of Firmicutes and Actinobacteria significantly.It was beneficial to the improvement of soil bacterial activity and fertility under 120 mg kg^-1 N with reclaimed water irrigation.
文摘The emission of the traditional energy chemical industry accounts for 20% of the total manmade VOC emission in China, of which coal chemical and petrochemical plants are one of the most important VOC emission sources. VOC emission sources mainly include the leakage of oil refinery units and equipment, pipes and valves, respiration and leakage of various types of storage tanks, effusion of oils during loading and unloading, effusion of sewage treatment systems, all kinds of process tail gas, etc. In this paper, the current management status of VOC emission in China’s coal chemical industry and petrochemical industry are analyzed, which divides VOC management into intentional and fugitive emission. The Leak Detection and Repair (LDAR) management method and technology for equipment, pipes and valves implemented in the United States are studied to propose self-inspection management methods and measures for VOC emissions in the energy chemical industry, providing strategies and recommendations for energy conservation, emission reduction and cleaner production in the traditional energy chemical industry.
文摘In the etiology of hepatocellular carcinoma (HCC), in addition to hepatitis B virus and hepatitis C virus infections, chemical carcinogens also play important roles. For example, aflatoxin B 1 (AFB 1 ) epoxide reacts with guanine in DNA and can lead to genetic changes. In HCC, the tumor suppressor gene p53 codon 249 mutation is associated with AFB 1 exposure and mutations in the K -ras oncogene are related to vinyl chloride exposure. Numerous genetic alterations accumulate during the process of hepatocarcinogenesis. Chemical carcinogen DNA-adduct formation is the basis for these genetic changes and also a molecular marker which reflects exposure level and biological effects. Metabolism of chemical carcinogens, including their activation and detoxification, also plays a key role in chemical hepatocarcinogenesis. Cytochrome p450 enzymes, N -acetyltransferases and glutathione S -transferases are involved in activating and detoxifying chemical carcinogens. These enzymes are polymorphic and genetic variation influences biological response to chemical carcinogens. This genetic variation has been postulated to influence the variability in risk for HCC observed both within and across populations. Ongoing studies seek to fully understand the mechanisms by which genetic variation in response to chemical carcinogens impacts on HCC risk.
文摘The hydrodynamic research about the droplet condensing of the multi phase liquid state on the surface of the coal glass and water discusses the deepening process of convex shape curve and the formation of S shape, and puts emphasis on describing the diagram formation method of the later. In the induction period the active diagram of the micro droplet is decided by pH value forming as convex shape diagram or S shape diagram. When pH value is above 4.0, the damage of convex shape diagram cannot be recovered, in that case produce S shape activity diagram. When pH value is equal to or above 12.0, the hard surface with alkali liquid state loses adhesion, so that the micro droplet condensing of the multi phase liquid state stops completely. The research result shows that the water cleaning conditions of getting rid of the oil micro droplets can be decided by the pH value.
基金Supported by China Agricultural Research System ( CARS-02)
文摘Athetis lepigone Moschler is a new kind of insect pest occurring in summer corn production areas. By investigation, it was found especially serious in straw returning fields. In this paper, its damage status was investigated in straw returning and chemical controlled fields, respectively. The results showed that the rate of damaged plants was 82% and the maximum pest number per 100 plants was 88 heads in the straw returning fields without chemical control. The application of herbicides and pesticides had no significant effects on occurrence quantity and damage rate, but the pest number per 100 plants decreased a little compared to the fields without chemical control. In the surer er maize fields without straw returning, the application of herbicides and pesticides could significantly decrease the damage of Athetis lepigone, the rate of damaged plants was 20%, and the pest number per 100 plants was 6.