Since the introduction of the membrane bioreactor(MBR)in China in the early 1990s,remarkable progress has been achieved on the research and application of this technology.China has now become one of the most active fi...Since the introduction of the membrane bioreactor(MBR)in China in the early 1990s,remarkable progress has been achieved on the research and application of this technology.China has now become one of the most active fields in the world in this regard.This review outlines the development of MBR-based processes in China and their performance of treating municipal and industrial wastewaters.Since membrane fouling is a critical operational problem with MBR processes,this paper also proposes updated understanding of fouling mechanisms and strategies of fouling control,which are mainly compiled from publications of Chinese researchers.As for the commercial application of MBR in the country,the latest statistics of large-scale MBR plants(>10000 m^(3)·d^(–1))are provided,and the growth trend of total treatment capacity as well as its driving force is analyzed.展开更多
In this work, three widely used commercial Zn alloys (ZA4-1, ZA4-3, ZA6-1 ) were purchased and pre- pared by hot extrusion at 200℃. The microstructure, mechanical properties, corrosion behaviors, biocompatibility a...In this work, three widely used commercial Zn alloys (ZA4-1, ZA4-3, ZA6-1 ) were purchased and pre- pared by hot extrusion at 200℃. The microstructure, mechanical properties, corrosion behaviors, biocompatibility and hemocompatibility of Zn alloys were studied with pure Zn as control, Commercial Zn alloys demonstrated increased strength and superb elongation compared with pure Zn. Accelerated corrosion rates and uniform corrosion morphologies were observed in terms of commercial Zn alloys due to galvanic effects between Zn matrix and α-Al phases. 100% extracts of ZA4-1 and ZA6-1 alloys showed mild cytotoxicity while 50% extracts of all samples displayed good biocompatibility. Retardant cell cycle and inhibited stress fibers expression were observed induced by high concentration of Zn^2+ releasing during corrosion. The hemolysis ratios of Zn alloys were lower than 1% while the adhered platelets showed slightly activated morphologies. In general, commercial Zn alloys possess promising mechanical properties, appropriate corrosion rates, significantly improved biocompatibility and good hemocompatibility in comparison to pure Zn. It is feasible to develop biodegradable metals based on commercial Zn alloys.展开更多
Modifying effect and mechanism of trace rare earth on Fe(Si) rich impurity phases in commercial purity aluminum were studied with the aids of SEM, EDAX, TEM, etc. It is found that Ce rich mixed rare earth (RE) is an...Modifying effect and mechanism of trace rare earth on Fe(Si) rich impurity phases in commercial purity aluminum were studied with the aids of SEM, EDAX, TEM, etc. It is found that Ce rich mixed rare earth (RE) is an effective modifying agent, which makes the coarse Fe rich impurity phases transform into complex compounds of tiny, sphere/short stick form, thus improving mechanical properties of this material; its modifying mechanism is in that RE gathering in front of solid/liquid interface enters into the impurity phases, forming complex (AlFeSiRE) compounds; or is adsorbed in the impurity phases surface, impeding the growth of impurity phases; however, excessive RE will result in the increasing of RE compounds (secondary phases), and plasticity reduction of this material. Therefore, its addition amount should be less than 0 07% (mass fraction).展开更多
This review describes the present hot research areas of mangrove-associated fungi, including its biodiversity, ecological roles, novel metabolites productions and biotechnological potential. Mangrove-associated fungi ...This review describes the present hot research areas of mangrove-associated fungi, including its biodiversity, ecological roles, novel metabolites productions and biotechnological potential. Mangrove-associated fungi were divided into saprophytic, parasitic and true symbiotic fungi based on its ecological roles. Saprophytic fungi are fundamental to decomposition and energy flow of mangrove, additionally, their potential toxicity also exists. Pathogenic fungi have significant effects on mangrove survival, growth, and fitness. Endophytic fungi, the most prolific source of diverse bioactive compounds found among that of mangrove-associated fungi, are found in most species of mangroves. Although a significant number of reports focused on the antimicrobial, insecticidal and other bioactive metabolites as well as many novel enzymes isolatcd from mangrove-associated fungi, and many of those metabolites from endophytic fungi are suspected to be of significant to mangrove, only few studies have provided convincing evidence for symbiotic producers in mangrove. Hence, this paper discusses the present progress of molecular methods used to correlate the ecological roles of endophytic fungi with their bioactive metabolites;, meanwhile, the potential of using metabolic engineering and post-genomic approaches to isolate more novel enzymes and bioactive compounds and to make their possible commercial application was also discussed.展开更多
Meat quality traits of four genotypes of Chinese indigenous chicken [Ninghai chicken(NC),frizzle chicken(FC),Ninghai xiang chicken(XC),and Zhenning loquat chicken(LC)] and one genotype of commercial broiler [Arbor Acr...Meat quality traits of four genotypes of Chinese indigenous chicken [Ninghai chicken(NC),frizzle chicken(FC),Ninghai xiang chicken(XC),and Zhenning loquat chicken(LC)] and one genotype of commercial broiler [Arbor Acres plus broiler(AAB)] were analyzed.The indigenous chickens were raised before the commercial chickens in order to achieve the same final processed days.Indigenous chickens of NC,FC,XC,and LC showed significantly higher inosine-5′-monophosphate(IMP) content,shorter fiber diameter,and lower shear force than those of AAB(P<0.05).In the indigenous genotypes,NC and FC had significantly shorter fiber diameters and lower shear forces than XC and LC(P<0.05),and NC and XC had a higher IMP content than FC and LC(P<0.05).Moreover,the indigenous genotype of LC significantly displayed the highest protein content(P<0.05) in the five genotypes of birds,and no significant differences of protein content were found between the other genotypes of NC,FC,XC,and AAB(P>0.05).The indigenous chickens from FC displayed the highest total lipid content in the five bird genotypes(P<0.05).Significant differences of pH,color values of L* and a*,and drip loss for the five genotypes of birds were also observed.In conclusion,there were significant differences in the meat quality traits of the bird breeds selected in this study,and the indigenous chickens,especially the NC genotype,produced better quality meat as far as the IMP content,fiber diameters,and shear forces were concerned.展开更多
Length-frequency data of eight commercial fish species in the Beibu Gulf (Golf of Tonkin), northern South China Sea, were collected during 2006-2007. Length-weight relationships and growth and mortality parameters w...Length-frequency data of eight commercial fish species in the Beibu Gulf (Golf of Tonkin), northern South China Sea, were collected during 2006-2007. Length-weight relationships and growth and mortality parameters were analyzed using FiSAT II software. Five species had isometric growth, two species had negative allometric growth, and one species had positive allometric growth. Overall, the exploitation rates of the eight species were lower in 2006 2007 than in 1997-1999: for four species (Saurida tumbil, Saurida undosquamis, Argyrosomus macrocephalus, and Nemipterus virgatus) it was lower in 2006-2007 than in 1997 1999, for two species (Parargyrops edita and Trichiurus haumela) it remained the same, and for the other two species (Trachurus japonicus and Decapterus maruadsi) it was higher in 2006~007 than in 1997-1999. The exploitation rates might have declined because of the decline in fishing intensity caused by high crude oil prices. The optimum exploitation rate, estimated using Beverton-Holt dynamic pool models, indicated that although fishes in the Beibu Gulf could sustain high exploitation rates, the under-size fishes at first capture resulted in low yields. To increase the yield per recruitment, it is more effective to increase the size at first capture than to control fishing effort.展开更多
Microstructures of three kinds of typical product states for commercially fabricated alloy 2195 were observed.It is found that the hot-rolled plate is characterized by a fibrous structure containing fine,polygonized s...Microstructures of three kinds of typical product states for commercially fabricated alloy 2195 were observed.It is found that the hot-rolled plate is characterized by a fibrous structure containing fine,polygonized substructures;and the cold-rolled sheet was characterized by a "pan-caked" grain structure containing high density dislocation cells.The product under near peak-aging temper is proved to contain a large amount of dispersive,plate-shaped T1(Al2CuLi) precipitates,together with a small fraction of θ'(Al2Cu) plates,exhibiting a desirable combination of mechanical properties.Analyses using scanning electron microscopy reveal that many coarse,irregular-shaped Al7Cu2Fe constituent particles exist in all product states,which indicates that intermediate heat treatments have little influence on this iron-caused,detrimental phase.The formation and evolution of microstructures for different product states of alloy 2195 were discussed in view point of the commercial production condition.展开更多
基金the National Science Fund for Distinguished Young Scholars(Grant No.50725827)the National High Technology Research and Development Program(863 program)of China(Grant No.2009AA062901).
文摘Since the introduction of the membrane bioreactor(MBR)in China in the early 1990s,remarkable progress has been achieved on the research and application of this technology.China has now become one of the most active fields in the world in this regard.This review outlines the development of MBR-based processes in China and their performance of treating municipal and industrial wastewaters.Since membrane fouling is a critical operational problem with MBR processes,this paper also proposes updated understanding of fouling mechanisms and strategies of fouling control,which are mainly compiled from publications of Chinese researchers.As for the commercial application of MBR in the country,the latest statistics of large-scale MBR plants(>10000 m^(3)·d^(–1))are provided,and the growth trend of total treatment capacity as well as its driving force is analyzed.
基金supported by the National Basic Research Program of China (973 Program) (Grant Nos. 2012CB619102 and 012CB619100)National Science Fund for Distinguished Young Scholars (Grant No. 51225101)+3 种基金National Natural Science Foundation of China (Grant Nos. 51431002 and 31170909)the NSFC/RGC Joint Research Scheme (Grant No. 51361165101)State Key Laboratory for Mechanical Behavior of Materials (Grant No. 20141615)Beijing Municipal Science and Technology Project (No. Z141100002814008)
文摘In this work, three widely used commercial Zn alloys (ZA4-1, ZA4-3, ZA6-1 ) were purchased and pre- pared by hot extrusion at 200℃. The microstructure, mechanical properties, corrosion behaviors, biocompatibility and hemocompatibility of Zn alloys were studied with pure Zn as control, Commercial Zn alloys demonstrated increased strength and superb elongation compared with pure Zn. Accelerated corrosion rates and uniform corrosion morphologies were observed in terms of commercial Zn alloys due to galvanic effects between Zn matrix and α-Al phases. 100% extracts of ZA4-1 and ZA6-1 alloys showed mild cytotoxicity while 50% extracts of all samples displayed good biocompatibility. Retardant cell cycle and inhibited stress fibers expression were observed induced by high concentration of Zn^2+ releasing during corrosion. The hemolysis ratios of Zn alloys were lower than 1% while the adhered platelets showed slightly activated morphologies. In general, commercial Zn alloys possess promising mechanical properties, appropriate corrosion rates, significantly improved biocompatibility and good hemocompatibility in comparison to pure Zn. It is feasible to develop biodegradable metals based on commercial Zn alloys.
文摘Modifying effect and mechanism of trace rare earth on Fe(Si) rich impurity phases in commercial purity aluminum were studied with the aids of SEM, EDAX, TEM, etc. It is found that Ce rich mixed rare earth (RE) is an effective modifying agent, which makes the coarse Fe rich impurity phases transform into complex compounds of tiny, sphere/short stick form, thus improving mechanical properties of this material; its modifying mechanism is in that RE gathering in front of solid/liquid interface enters into the impurity phases, forming complex (AlFeSiRE) compounds; or is adsorbed in the impurity phases surface, impeding the growth of impurity phases; however, excessive RE will result in the increasing of RE compounds (secondary phases), and plasticity reduction of this material. Therefore, its addition amount should be less than 0 07% (mass fraction).
基金Foundation project: This work was supported partly by the Guangzhou Natural Science Foundation (Grant No. 2007Z3-EO581), the Guangdong Provincial Natural Science Foundation (Grant No. 2007A0200300001-7 05003268), the Chinese High-Tech 863 Project (Grant No. 2006AA09Z422), and the National Natural Science Foundation of China (Grant No. 20572136).
文摘This review describes the present hot research areas of mangrove-associated fungi, including its biodiversity, ecological roles, novel metabolites productions and biotechnological potential. Mangrove-associated fungi were divided into saprophytic, parasitic and true symbiotic fungi based on its ecological roles. Saprophytic fungi are fundamental to decomposition and energy flow of mangrove, additionally, their potential toxicity also exists. Pathogenic fungi have significant effects on mangrove survival, growth, and fitness. Endophytic fungi, the most prolific source of diverse bioactive compounds found among that of mangrove-associated fungi, are found in most species of mangroves. Although a significant number of reports focused on the antimicrobial, insecticidal and other bioactive metabolites as well as many novel enzymes isolatcd from mangrove-associated fungi, and many of those metabolites from endophytic fungi are suspected to be of significant to mangrove, only few studies have provided convincing evidence for symbiotic producers in mangrove. Hence, this paper discusses the present progress of molecular methods used to correlate the ecological roles of endophytic fungi with their bioactive metabolites;, meanwhile, the potential of using metabolic engineering and post-genomic approaches to isolate more novel enzymes and bioactive compounds and to make their possible commercial application was also discussed.
基金Project supported by the Zhejiang Provincial Public Technology Application Research Project(No.2012C22052)the Hangzhou Science and Technology Development Project(Nos.20120232B72and 20101032B18)the General Administration of Quality Supervision,Inspection and Quarantine of China(No.201310120)
文摘Meat quality traits of four genotypes of Chinese indigenous chicken [Ninghai chicken(NC),frizzle chicken(FC),Ninghai xiang chicken(XC),and Zhenning loquat chicken(LC)] and one genotype of commercial broiler [Arbor Acres plus broiler(AAB)] were analyzed.The indigenous chickens were raised before the commercial chickens in order to achieve the same final processed days.Indigenous chickens of NC,FC,XC,and LC showed significantly higher inosine-5′-monophosphate(IMP) content,shorter fiber diameter,and lower shear force than those of AAB(P<0.05).In the indigenous genotypes,NC and FC had significantly shorter fiber diameters and lower shear forces than XC and LC(P<0.05),and NC and XC had a higher IMP content than FC and LC(P<0.05).Moreover,the indigenous genotype of LC significantly displayed the highest protein content(P<0.05) in the five genotypes of birds,and no significant differences of protein content were found between the other genotypes of NC,FC,XC,and AAB(P>0.05).The indigenous chickens from FC displayed the highest total lipid content in the five bird genotypes(P<0.05).Significant differences of pH,color values of L* and a*,and drip loss for the five genotypes of birds were also observed.In conclusion,there were significant differences in the meat quality traits of the bird breeds selected in this study,and the indigenous chickens,especially the NC genotype,produced better quality meat as far as the IMP content,fiber diameters,and shear forces were concerned.
基金Supported by the Chinese Ministry of Agriculture under the Investigation of Fishery Stocks in China Seas Program (No. 070404)the Special Project of the Social Commonwealth Research National Institute (Nos.2009TS08, 2010YD10)
文摘Length-frequency data of eight commercial fish species in the Beibu Gulf (Golf of Tonkin), northern South China Sea, were collected during 2006-2007. Length-weight relationships and growth and mortality parameters were analyzed using FiSAT II software. Five species had isometric growth, two species had negative allometric growth, and one species had positive allometric growth. Overall, the exploitation rates of the eight species were lower in 2006 2007 than in 1997-1999: for four species (Saurida tumbil, Saurida undosquamis, Argyrosomus macrocephalus, and Nemipterus virgatus) it was lower in 2006-2007 than in 1997 1999, for two species (Parargyrops edita and Trichiurus haumela) it remained the same, and for the other two species (Trachurus japonicus and Decapterus maruadsi) it was higher in 2006~007 than in 1997-1999. The exploitation rates might have declined because of the decline in fishing intensity caused by high crude oil prices. The optimum exploitation rate, estimated using Beverton-Holt dynamic pool models, indicated that although fishes in the Beibu Gulf could sustain high exploitation rates, the under-size fishes at first capture resulted in low yields. To increase the yield per recruitment, it is more effective to increase the size at first capture than to control fishing effort.
基金supported by the National Key Technologies R&D Program of China during the 10th Five-year Plan Period
文摘Microstructures of three kinds of typical product states for commercially fabricated alloy 2195 were observed.It is found that the hot-rolled plate is characterized by a fibrous structure containing fine,polygonized substructures;and the cold-rolled sheet was characterized by a "pan-caked" grain structure containing high density dislocation cells.The product under near peak-aging temper is proved to contain a large amount of dispersive,plate-shaped T1(Al2CuLi) precipitates,together with a small fraction of θ'(Al2Cu) plates,exhibiting a desirable combination of mechanical properties.Analyses using scanning electron microscopy reveal that many coarse,irregular-shaped Al7Cu2Fe constituent particles exist in all product states,which indicates that intermediate heat treatments have little influence on this iron-caused,detrimental phase.The formation and evolution of microstructures for different product states of alloy 2195 were discussed in view point of the commercial production condition.