Chronic alcohol consumption induces hepatic steatosis, the early stage of alcoholic liver disease （ALD）. The aim ofpresent study is to investigate the protective effect ofPanax notoginseng saponins （PNS） against c...Chronic alcohol consumption induces hepatic steatosis, the early stage of alcoholic liver disease （ALD）. The aim ofpresent study is to investigate the protective effect ofPanax notoginseng saponins （PNS） against chronic ethanol-induced hepaticsteatosis in vivo. Mice were pair-fed a modified Lieber-DeCarli liquid diet containing alcohol or isocaloric maltose dextrin ascontrol diet with or without PNS （200 mg/kg, BW） for 8 weeks. Animals supplemented with PNS were protected against hepaticlipid accumulation induced by chronic ethanol exposure. Accordingly, PNS could significantly decrease the elevation of plasmatriglyceride, plasma enzyme activities, i.e. alanine aminotransferase （ALT） and aspartate aminotransferase （AST）, and hepaticTNF-ct and IL-6 levels which were induced by chronic alcohol exposure. In addition, PNS markedly reduced the lipolysis ofwhite adipose tissue （WAT） that stimulated by alcohol feeding through the inhibiting protein expression of phosphorylation ofhormone-sensitive lipase （p-HSL）, rather than total HSL. Furthermore, alcohol exposure also enhanced fatty acid uptake capacityin liver by elevated hepatic CD36 expression, which could attenuated by PNS treatment. These results demonstrate that PNSsupplementation protects against chronic ethanol-induced hepatic steatosis, which is associated with ameliorating dysfunctionallipid metabolism of WAT and the reduced inflammatory cytokines. Our findings suggested that PNS might be potential to bedeveloped as an effective agent for the treatment of chronic alcoholic steatosis.展开更多
The effluent from the pulping of E. urophylla by alkali sodium sulfite chemi mechanical process(AS-CMP) was characterized for its biodegradability by photosynthetic bacteria (PSB). Chemical coagulation post treat...The effluent from the pulping of E. urophylla by alkali sodium sulfite chemi mechanical process(AS-CMP) was characterized for its biodegradability by photosynthetic bacteria (PSB). Chemical coagulation post treatment of biotreated wastewater was also studied. One month continuous treatment in the laboratory indicated that the COD Cr , BOD 5 and SS removals in biotreatment stages reached 56%, 83% and 89% respectively, and the CH 2Cl 2 extractives decreased from 10.7 mg/L to 7.7 mg/L. In chemical coagulation post treatment stage, the effects of process conditions, such as coagulant dosage, pH value and the coordinated coagulation flocculation treatment of three kinds of coagulants on coagulation effectiveness were discussed. The optimum operating conditions were given.展开更多
Membrane fouling curtails severely the economical and practical implementation of membrane process. The fundamental principles and mechanisms of membrane fouling as well as factors affecting fouling have been summariz...Membrane fouling curtails severely the economical and practical implementation of membrane process. The fundamental principles and mechanisms of membrane fouling as well as factors affecting fouling have been summarized in this paper. It also has covered three fouling resistance models and four kinds of approaches to improve membrane performance. Membrane cleaning methods are also discussed including physical, chemical, physico\|chemical and biological methods. In the four groups of basic cleaning methods, biological cleaning has considerable advantages and potentials. Extensive research work should be carried out further to explore and develop new ideas and techniques in the field of membrane cleaning and restoration.展开更多
Nanometer perovskite LaMnO 3+λ, La 0.6Ce 0.4MnO 3+λ and La 0.6Sr 0.4MnO 3+λ were prepared by citric acid-aid ed sol-gel method. The effects of Ce, Sr on the structure and properties of nan ome...Nanometer perovskite LaMnO 3+λ, La 0.6Ce 0.4MnO 3+λ and La 0.6Sr 0.4MnO 3+λ were prepared by citric acid-aid ed sol-gel method. The effects of Ce, Sr on the structure and properties of nan ometer perovskite were studied through DT-TGA, XRD, TEM and BET analyses. The r esults show that, by sol-gel method, LaMnO 3+λ, La 0.6Ce 0. 4MnO 3+λ and La 0.6Sr 0.4MnO 3+λ were made with average particle size of about 60, 100 and 30 nm, respectively. After partially substituting Sr on La positions in LaMnO 3+λ, it is found that Sr is l ocated at the perovskite lattice so as to reduce the formation temperature of th e perovskite. As a result, the perovskite has a smaller particle size and larger specific surface area. On the contrary, it is difficult for Ce to enter the per ovskite lattice. Ce exists mostly in the form of CeO 2 as partially substitutin g La in LaMnO 3+λ. The formation temperature of the perovskite increas es, and the catalyst containing CeO 2 presents a larger particle size and less specific surface area.展开更多
In order to study the feasibility of treating petro chemical wastewater by the combination of anaerobic and aerobic biological process, a research of treating wastewater in UASB reactor and aeration basin has been co...In order to study the feasibility of treating petro chemical wastewater by the combination of anaerobic and aerobic biological process, a research of treating wastewater in UASB reactor and aeration basin has been conducted. The test results shows that under moderate temperature, with 5\^2 kgCOD/(m\+3·d) volumetric load of COD Cr in the UASB reactor and 24h of HRT, 85% removal rate of BOD 5 and 83% of COD \{Cr\} and 1\^34 m\+3/(m\+3·d) volumetric gas production rate can be obtained respectively. The aerobic bio degradability can be increased by 20%—30% after the petro chemical wastewater has been treated by anaerobic process. As Ns=0\^45 kgCOD/(kgMLSS·d), HRT=4h in the aeration tank, 94% removal rate of BOD 5, 93% of COD \{Cr\}, 98\^8% total removal rate of COD \{Cr\} and 99% removal rate of BOD 5 can be reached.展开更多
Destruction of trichloro ethylene (C 2HCl 3) by pulsed corona discharge reactor packed with alumina pellets and in absence of packing was investigated. Higher conversion of C 2HCl 3 was observed in presence of alu...Destruction of trichloro ethylene (C 2HCl 3) by pulsed corona discharge reactor packed with alumina pellets and in absence of packing was investigated. Higher conversion of C 2HCl 3 was observed in presence of alumina than in absence of packing. Furthermore CO/CO 2 ratio in the by products was found to shift in favor of CO 2 by alumina compared with absence of packing. Influence of catalyst porosity on C 2HCl 3 destruction and on by product ozone generation during the processing was also studied. Both alumina Ⅰ and alumina Ⅱ show similar improvement in C 2HCl 3 destruction. However, more important observation was that alumina Ⅰ produces higher by product ozone, while, alumina Ⅱ produces lower by product ozone, than in the case of no packing. The catalyst porosity effect was also investigated for destruction of toluene and was found to be similar. Intermediates of C 2HCl 3 destruction, as identified by GC MS, were COCl 2, CH 2Cl 2CHCl 3, CCl 4 and C 2HCl 5. In presence of alumina the amount of these intermediates was much reduced, indicating the catalytic function of alumina.展开更多
Ecosystem health is a newly proposed concept that sets new goals for environmental management. Its definition, assessment indicators, and assessment methods are reviewed in this paper. Literature shows that the defini...Ecosystem health is a newly proposed concept that sets new goals for environmental management. Its definition, assessment indicators, and assessment methods are reviewed in this paper. Literature shows that the definitions and the assessment indicators cover a wide range of ecosystem health, and they differ in terms of researchers different scientific background. It is concluded that the concept of ecosystem health cannot be defined or understood simply in biological or ethical or aesthetic or historical terms and the assessment should be based on applying several indicators simultaneously to get overall picture of the health or integrity state of an ecosystem.展开更多
To demonstrate the feasibility of using bioaugmentation to enhance biodegradation of quinoline, four strains capable of using quinoline as sole source of carbon, nitrogen and energy were isolated from different enviro...To demonstrate the feasibility of using bioaugmentation to enhance biodegradation of quinoline, four strains capable of using quinoline as sole source of carbon, nitrogen and energy were isolated from different environmental samples by enrichment technique. Screening for quinoline degrader with the highest quinoline mineralizing rate was carried out in respirometer and one bacterium identified as \%Burkholderia pickettii W2\% was chosen as inoculum in bioaugmentation tests. Quinoline biodegradation experiment results showed that this bacterium degraded quinoline very quickly. 100, 200 and 500 mg/L quinoline can be transformed completely within 1, 2 and 7 hours respectively. A bioaugmentation procedure was proposed and laboratory experiments confirmed that bioaugmentation was an effective way to improve the performance of traditional wastewater treatment facilities for quinoline removal. The effect of inoculum size on bioaugmentation was also investigated in this paper.展开更多
This paper studied the change in soil animal community in contaminated and irrigated area by organophosphorus pesticide waste water and its mechanism was discussed. The results showed that the species and quantities o...This paper studied the change in soil animal community in contaminated and irrigated area by organophosphorus pesticide waste water and its mechanism was discussed. The results showed that the species and quantities of soil animals decreased with organophosphorus pesticide pollution degree increasing. The species of soil animals decreased with average and rare population mainly decreasing, while the amount change was associated with that of the dominant population of Acarina, Collembola and Nematoda. Toxicity experiment demonstrated that the respiration intensity of soil animal was restrained obviously by pesticide pollution. After observation of SEM, the effect of pesticide pollution on the earthworm (\%Pheretima robusta)\% stomach intestinal mucosa damage has been observed, which showed the pesticide contamination may damage the earthworms bodies. Ulcerous focus and perforation on stomach mucosa were usually seen. The stomach microvilli appeared atrophic and disordered especially in the bodies of these earthworms growing in seriously polluted soil, bad atrophic phenomena were seen not only on the stomach mucosa microvilli but also on the cilia of the intestinal mucosa which appeared swollen as a spheroid. Under TEM, RER and Golgi compound dilatation, chondrisome swell and ridge disappearance were observed on cells of stomach epithelium mucosa of \%P.robusta\% collected from heavy polluted area. By calculation, the safety concentration of earthworm in methamidophos pesticide is 0\^2517 ml/L.展开更多
Based upon the deep seismic sounding profile conducted in the Tengchong volcanic-geothermal area, a two-dimensional crustal P velocity structure is obtained by use of the finite-difference inversion and the forward tr...Based upon the deep seismic sounding profile conducted in the Tengchong volcanic-geothermal area, a two-dimensional crustal P velocity structure is obtained by use of the finite-difference inversion and the forward travel-time fitting method. The crustal model shows that there is a low velocity zone in upper crust in the Tengchong area, which may be related to the volcanic-geothermal activities, and two intracrustal faults (the LonglingRuili fault and Tengchong fault) exist on the profile, where the Tengchong fault may extend to the Moho discontinuity. Meanwhile, based on teleseismic data recorded by a temporary seismic network, we obtained the S-wave velocity structures beneath the RehaiRetian region in the Tengchong area, which show the low S-wave velocity anomaly in upper crust. The authors discuss the causes of Tengchong volcanic eruption based on the deep crustal structure. The crustal structure in the Tengchong volcanic-geothermal area is characterized by low P-wave and S-wave velocity, low resistivity, high heat-flow value and low Q value. The P-wave velocity in the upper mantle is also low. For this information, it can be induced that the magma in the crust is derived from the upper mantle, and the low velocity anomaly in upper crust in the Tengchong area may be related to the differentiation of magma. The Tengchong volcanoes are close to an active plate boundary and belong to plate boundary volcanoes.展开更多
The additives such as phosphoric acid, calcium phosphate, calcium super phosphate, calcium over super phosphate, calcium carbonate, sodium hydrosulphite, etc. were used to produce furfural from the straw by hydrolys...The additives such as phosphoric acid, calcium phosphate, calcium super phosphate, calcium over super phosphate, calcium carbonate, sodium hydrosulphite, etc. were used to produce furfural from the straw by hydrolysis with sulfuric acid. The effect of amount of the additives, the content of the added substance and the conditions of distillation on the acidity of the residues were studied. The experiment results showed that the all residues became neutral complex fertilizer, and the productivity of furfural increases under the following conditions: sulfuric acid concentration is 20% (by weight), the ratio of liquid to solid is 3∶1—4∶1 (by weight), the ratio of the additives to straw is suitable.展开更多
With the rapid economic development and the speeding up of urbanization, the urban environmental problems in China are experiencing a progressive transition, which is characterized by steady transferring to the living...With the rapid economic development and the speeding up of urbanization, the urban environmental problems in China are experiencing a progressive transition, which is characterized by steady transferring to the living (or consumption) oriented pollution pattern from the production oriented pollution pattern. Regarding this transition, the environmental education recognized as an important measure for approaching the objective of sustainable development, should transfer its focus correspondingly in urban area, which is to transfer to the habit cultivating pattern on the basis of the traditional knowledge inputting environmental education pattern. In practice, the urban environmental education should emphasize more on developing or cultivating the sustainable living mode of the urban residents, especially the students in elementary and primary schools and women. By this transform, the environmental education may be guided further towards sustainable development, and to serve the achievement of sustainable cities better in China.展开更多
A series solution for surface motion amplification due to underground group cavities for incident plane P waves is derived by Fourier-Bessel series expansion method. It is shown that underground group cavities signifi...A series solution for surface motion amplification due to underground group cavities for incident plane P waves is derived by Fourier-Bessel series expansion method. It is shown that underground group cavities significantly am-plify the surface ground motion nearby. It is suggested that the effect of subways on ground motion should be con-sidered when the subways are planned and designed.展开更多
To understand the earthquake characteristics in Xinfengjiang (XFJ for short) reservoir area, we collected the small earthquakes occurred in the area from 1961 to 1999. We segmented this 40-year period, parted the rese...To understand the earthquake characteristics in Xinfengjiang (XFJ for short) reservoir area, we collected the small earthquakes occurred in the area from 1961 to 1999. We segmented this 40-year period, parted the research region and calculated the composite fault plane solution of each block, disscussed the effect characteristics of stress field of water pressure using Mohrs stress circle. The final result shows that the main rupture pattern was very different before and after the M = 6.1 main shock, changing from strike slip to normal rupture. The maximum principal stress axes of composite fault plane solutions are characterized by synchronous change with water level.展开更多
A numerical model has been developed to simulate the transport and fate of oil spilled at sea. The model combines the transport and fate processes of spilled oil with the random walk technique. Oil movement under th...A numerical model has been developed to simulate the transport and fate of oil spilled at sea. The model combines the transport and fate processes of spilled oil with the random walk technique. Oil movement under the influence of tidal currents, wind driven currents, and turbulent eddies is simulated by the PLUME RW dispersion model developed by HR Wallingford. The weathering processes in the model represent physical and chemical changes of soil slicks with time, and comprise mechanical spreading, dispersion, evaporation and emulsification. Shoreline stranding is determined approximately using a capacity method for different shoreline types. This paper presents details of the model, and describe the results of various sensitivity tests. The model is suitable for oil spill contingency planning.展开更多
The acidic wastewater containing manganese and other heavy metal ions came from the plant which produce titanium dioxide in the method of the sulfuric acid digestion was disposed under the processes of the pre\|neutra...The acidic wastewater containing manganese and other heavy metal ions came from the plant which produce titanium dioxide in the method of the sulfuric acid digestion was disposed under the processes of the pre\|neutralization with the mineral containing phosphorus and calcium, alkaline precipitation and re\|regulating pH with the raw wastewater. The removal ratio of manganese and ferrous were higher than 99% and 98%, respectively, when the concentration of manganese and ferrous were 46 mg/L and 2000 mg/L. More than 5800 mg/L of SO\+\{2-\}\-4 were neutralized also. The effluent pH was the range between 6 and 9, the concentration of other pollution substances were all very lower even have not discoveried.展开更多
Polyferric\|silicate\|sulfate(PFSS),as a new type of coagulant,was prepared by using sodium silicate, sulfuric acid and ferric sulfate as materials.The zeta potential of hydrolyzate of PFSS under different pH values w...Polyferric\|silicate\|sulfate(PFSS),as a new type of coagulant,was prepared by using sodium silicate, sulfuric acid and ferric sulfate as materials.The zeta potential of hydrolyzate of PFSS under different pH values was investigated.The effects of Fe/SiO\-2 molar ratio and dosage of PFSS on turbidity removal were studied. The relation between the optimum coagulation pH range and Fe/SiO\-2 molar ratio was found and the coagulation mechanism of PFSS was discussed.The experimental results showed that Fe/SiO\-2 molar ratio has an effect on the zeta potential of hydrolyzate, the coagulation performance and the optimum coagulation pH range of PFSS and that PFSS gives the best turbidity removal effect when its Fe/SiO\-2 molar ratio was 1.5.展开更多
The IC 50 values of 20 nitroaromatics were determined by the activity of ATPase of carp ( Cyprinus carpio ) kidney in vitro, and used to develop the quantitative structure activity relationship (QSAR) wi...The IC 50 values of 20 nitroaromatics were determined by the activity of ATPase of carp ( Cyprinus carpio ) kidney in vitro, and used to develop the quantitative structure activity relationship (QSAR) with 6 descriptors of 1 X v, Σσ -, I , 1 Ka , E LUMO , log P . A best equation was obtained by multiple regression analysis -log IC 50 =1 306 Σσ -+0 657 I +0 584E LUMO +2 852( r =0 925). Σσ - is the sum of substituent constants. I is the indicator variable. E LUMO is the energy of the lowest unoccupied orbital. Results showed that the Σσ -, I and E LUMO were closely correlated with toxicity of nitroaromatics. Some toxicity mechanisms by nitroaromatics are also discussed in this paper.展开更多
The transfer kinetics of phenol between aqueous phase and N,N di(methyl heptyl) acetaminde (N503) in kerosene has been studied using Lewis cell technique. The effects of the factors including the concentrations of p...The transfer kinetics of phenol between aqueous phase and N,N di(methyl heptyl) acetaminde (N503) in kerosene has been studied using Lewis cell technique. The effects of the factors including the concentrations of phenol in aqueous phase and organic phase, the concentration of N503 in organic phase, the acidity of aqueous phase, the stirring speed and the temperature on the rates of forward and backward extraction of phenol have been examined. The regularity of extraction rate has been obtained. According to experimental results, the rates of both forward and backward extraction of phenol might be controlled by diffusion process. The diffusion step of phenol from aqueous phase to interface for forward extraction and from interface to aqueous phase for backward extraction might be the rate controlling steps.展开更多
The novel ways for the filtration improvement of zinc hydroxide sludge precipitated from the zinc\|containing solutions was investigated. It was found that, when the zinc\|containing solutions were added to sodium hyd...The novel ways for the filtration improvement of zinc hydroxide sludge precipitated from the zinc\|containing solutions was investigated. It was found that, when the zinc\|containing solutions were added to sodium hydroxide solution, the filtration of the obtained precipitates was improved to some extent, depending on the molar ratios of OH\+-/Zn, in comparison with those obtained by conventional addition of hydroxide solution to zinc\|containing solution, even the ratios were kept the same in these two alkalization methods. The experimental results showed that such an improvement may be contributed to the presence of muddy precipitates formed homogeneously in the sludge. It was suggested that it was zinc\|containing solution that should be added into hydroxide solution, when the zinc was removed from aqueous solution by the precipitation of zinc hydroxides. As a result, the sludge obtained will be filtered and rinsed readily.展开更多
基金Research Committee of the University of Macao(Grant No.MYRG123-ICMS12 and MYRG111-ICMS13)from Macao Science and Technology Development Fund(Grant No.010/2013/A1)
文摘Chronic alcohol consumption induces hepatic steatosis, the early stage of alcoholic liver disease （ALD）. The aim ofpresent study is to investigate the protective effect ofPanax notoginseng saponins （PNS） against chronic ethanol-induced hepaticsteatosis in vivo. Mice were pair-fed a modified Lieber-DeCarli liquid diet containing alcohol or isocaloric maltose dextrin ascontrol diet with or without PNS （200 mg/kg, BW） for 8 weeks. Animals supplemented with PNS were protected against hepaticlipid accumulation induced by chronic ethanol exposure. Accordingly, PNS could significantly decrease the elevation of plasmatriglyceride, plasma enzyme activities, i.e. alanine aminotransferase （ALT） and aspartate aminotransferase （AST）, and hepaticTNF-ct and IL-6 levels which were induced by chronic alcohol exposure. In addition, PNS markedly reduced the lipolysis ofwhite adipose tissue （WAT） that stimulated by alcohol feeding through the inhibiting protein expression of phosphorylation ofhormone-sensitive lipase （p-HSL）, rather than total HSL. Furthermore, alcohol exposure also enhanced fatty acid uptake capacityin liver by elevated hepatic CD36 expression, which could attenuated by PNS treatment. These results demonstrate that PNSsupplementation protects against chronic ethanol-induced hepatic steatosis, which is associated with ameliorating dysfunctionallipid metabolism of WAT and the reduced inflammatory cytokines. Our findings suggested that PNS might be potential to bedeveloped as an effective agent for the treatment of chronic alcoholic steatosis.
文摘The effluent from the pulping of E. urophylla by alkali sodium sulfite chemi mechanical process(AS-CMP) was characterized for its biodegradability by photosynthetic bacteria (PSB). Chemical coagulation post treatment of biotreated wastewater was also studied. One month continuous treatment in the laboratory indicated that the COD Cr , BOD 5 and SS removals in biotreatment stages reached 56%, 83% and 89% respectively, and the CH 2Cl 2 extractives decreased from 10.7 mg/L to 7.7 mg/L. In chemical coagulation post treatment stage, the effects of process conditions, such as coagulant dosage, pH value and the coordinated coagulation flocculation treatment of three kinds of coagulants on coagulation effectiveness were discussed. The optimum operating conditions were given.
文摘Membrane fouling curtails severely the economical and practical implementation of membrane process. The fundamental principles and mechanisms of membrane fouling as well as factors affecting fouling have been summarized in this paper. It also has covered three fouling resistance models and four kinds of approaches to improve membrane performance. Membrane cleaning methods are also discussed including physical, chemical, physico\|chemical and biological methods. In the four groups of basic cleaning methods, biological cleaning has considerable advantages and potentials. Extensive research work should be carried out further to explore and develop new ideas and techniques in the field of membrane cleaning and restoration.
文摘Nanometer perovskite LaMnO 3+λ, La 0.6Ce 0.4MnO 3+λ and La 0.6Sr 0.4MnO 3+λ were prepared by citric acid-aid ed sol-gel method. The effects of Ce, Sr on the structure and properties of nan ometer perovskite were studied through DT-TGA, XRD, TEM and BET analyses. The r esults show that, by sol-gel method, LaMnO 3+λ, La 0.6Ce 0. 4MnO 3+λ and La 0.6Sr 0.4MnO 3+λ were made with average particle size of about 60, 100 and 30 nm, respectively. After partially substituting Sr on La positions in LaMnO 3+λ, it is found that Sr is l ocated at the perovskite lattice so as to reduce the formation temperature of th e perovskite. As a result, the perovskite has a smaller particle size and larger specific surface area. On the contrary, it is difficult for Ce to enter the per ovskite lattice. Ce exists mostly in the form of CeO 2 as partially substitutin g La in LaMnO 3+λ. The formation temperature of the perovskite increas es, and the catalyst containing CeO 2 presents a larger particle size and less specific surface area.
文摘In order to study the feasibility of treating petro chemical wastewater by the combination of anaerobic and aerobic biological process, a research of treating wastewater in UASB reactor and aeration basin has been conducted. The test results shows that under moderate temperature, with 5\^2 kgCOD/(m\+3·d) volumetric load of COD Cr in the UASB reactor and 24h of HRT, 85% removal rate of BOD 5 and 83% of COD \{Cr\} and 1\^34 m\+3/(m\+3·d) volumetric gas production rate can be obtained respectively. The aerobic bio degradability can be increased by 20%—30% after the petro chemical wastewater has been treated by anaerobic process. As Ns=0\^45 kgCOD/(kgMLSS·d), HRT=4h in the aeration tank, 94% removal rate of BOD 5, 93% of COD \{Cr\}, 98\^8% total removal rate of COD \{Cr\} and 99% removal rate of BOD 5 can be reached.
文摘Destruction of trichloro ethylene (C 2HCl 3) by pulsed corona discharge reactor packed with alumina pellets and in absence of packing was investigated. Higher conversion of C 2HCl 3 was observed in presence of alumina than in absence of packing. Furthermore CO/CO 2 ratio in the by products was found to shift in favor of CO 2 by alumina compared with absence of packing. Influence of catalyst porosity on C 2HCl 3 destruction and on by product ozone generation during the processing was also studied. Both alumina Ⅰ and alumina Ⅱ show similar improvement in C 2HCl 3 destruction. However, more important observation was that alumina Ⅰ produces higher by product ozone, while, alumina Ⅱ produces lower by product ozone, than in the case of no packing. The catalyst porosity effect was also investigated for destruction of toluene and was found to be similar. Intermediates of C 2HCl 3 destruction, as identified by GC MS, were COCl 2, CH 2Cl 2CHCl 3, CCl 4 and C 2HCl 5. In presence of alumina the amount of these intermediates was much reduced, indicating the catalytic function of alumina.
文摘Ecosystem health is a newly proposed concept that sets new goals for environmental management. Its definition, assessment indicators, and assessment methods are reviewed in this paper. Literature shows that the definitions and the assessment indicators cover a wide range of ecosystem health, and they differ in terms of researchers different scientific background. It is concluded that the concept of ecosystem health cannot be defined or understood simply in biological or ethical or aesthetic or historical terms and the assessment should be based on applying several indicators simultaneously to get overall picture of the health or integrity state of an ecosystem.
文摘To demonstrate the feasibility of using bioaugmentation to enhance biodegradation of quinoline, four strains capable of using quinoline as sole source of carbon, nitrogen and energy were isolated from different environmental samples by enrichment technique. Screening for quinoline degrader with the highest quinoline mineralizing rate was carried out in respirometer and one bacterium identified as \%Burkholderia pickettii W2\% was chosen as inoculum in bioaugmentation tests. Quinoline biodegradation experiment results showed that this bacterium degraded quinoline very quickly. 100, 200 and 500 mg/L quinoline can be transformed completely within 1, 2 and 7 hours respectively. A bioaugmentation procedure was proposed and laboratory experiments confirmed that bioaugmentation was an effective way to improve the performance of traditional wastewater treatment facilities for quinoline removal. The effect of inoculum size on bioaugmentation was also investigated in this paper.
文摘This paper studied the change in soil animal community in contaminated and irrigated area by organophosphorus pesticide waste water and its mechanism was discussed. The results showed that the species and quantities of soil animals decreased with organophosphorus pesticide pollution degree increasing. The species of soil animals decreased with average and rare population mainly decreasing, while the amount change was associated with that of the dominant population of Acarina, Collembola and Nematoda. Toxicity experiment demonstrated that the respiration intensity of soil animal was restrained obviously by pesticide pollution. After observation of SEM, the effect of pesticide pollution on the earthworm (\%Pheretima robusta)\% stomach intestinal mucosa damage has been observed, which showed the pesticide contamination may damage the earthworms bodies. Ulcerous focus and perforation on stomach mucosa were usually seen. The stomach microvilli appeared atrophic and disordered especially in the bodies of these earthworms growing in seriously polluted soil, bad atrophic phenomena were seen not only on the stomach mucosa microvilli but also on the cilia of the intestinal mucosa which appeared swollen as a spheroid. Under TEM, RER and Golgi compound dilatation, chondrisome swell and ridge disappearance were observed on cells of stomach epithelium mucosa of \%P.robusta\% collected from heavy polluted area. By calculation, the safety concentration of earthworm in methamidophos pesticide is 0\^2517 ml/L.
基金The Climb Program (95-S-05-01) of National Scientific and Technological Ministry of China, the Key Project (95-11-02) from China Seismological Bureau, the State Natural Sciences Foundation of China (49974020) and the Joint Earthquake S
文摘Based upon the deep seismic sounding profile conducted in the Tengchong volcanic-geothermal area, a two-dimensional crustal P velocity structure is obtained by use of the finite-difference inversion and the forward travel-time fitting method. The crustal model shows that there is a low velocity zone in upper crust in the Tengchong area, which may be related to the volcanic-geothermal activities, and two intracrustal faults (the LonglingRuili fault and Tengchong fault) exist on the profile, where the Tengchong fault may extend to the Moho discontinuity. Meanwhile, based on teleseismic data recorded by a temporary seismic network, we obtained the S-wave velocity structures beneath the RehaiRetian region in the Tengchong area, which show the low S-wave velocity anomaly in upper crust. The authors discuss the causes of Tengchong volcanic eruption based on the deep crustal structure. The crustal structure in the Tengchong volcanic-geothermal area is characterized by low P-wave and S-wave velocity, low resistivity, high heat-flow value and low Q value. The P-wave velocity in the upper mantle is also low. For this information, it can be induced that the magma in the crust is derived from the upper mantle, and the low velocity anomaly in upper crust in the Tengchong area may be related to the differentiation of magma. The Tengchong volcanoes are close to an active plate boundary and belong to plate boundary volcanoes.
文摘The additives such as phosphoric acid, calcium phosphate, calcium super phosphate, calcium over super phosphate, calcium carbonate, sodium hydrosulphite, etc. were used to produce furfural from the straw by hydrolysis with sulfuric acid. The effect of amount of the additives, the content of the added substance and the conditions of distillation on the acidity of the residues were studied. The experiment results showed that the all residues became neutral complex fertilizer, and the productivity of furfural increases under the following conditions: sulfuric acid concentration is 20% (by weight), the ratio of liquid to solid is 3∶1—4∶1 (by weight), the ratio of the additives to straw is suitable.
文摘With the rapid economic development and the speeding up of urbanization, the urban environmental problems in China are experiencing a progressive transition, which is characterized by steady transferring to the living (or consumption) oriented pollution pattern from the production oriented pollution pattern. Regarding this transition, the environmental education recognized as an important measure for approaching the objective of sustainable development, should transfer its focus correspondingly in urban area, which is to transfer to the habit cultivating pattern on the basis of the traditional knowledge inputting environmental education pattern. In practice, the urban environmental education should emphasize more on developing or cultivating the sustainable living mode of the urban residents, especially the students in elementary and primary schools and women. By this transform, the environmental education may be guided further towards sustainable development, and to serve the achievement of sustainable cities better in China.
基金Supported by National Natural Science Foundation of China (50378063), Excellent Young Teachers Program of MOE and SRF for ROCS, MOE.
文摘A series solution for surface motion amplification due to underground group cavities for incident plane P waves is derived by Fourier-Bessel series expansion method. It is shown that underground group cavities significantly am-plify the surface ground motion nearby. It is suggested that the effect of subways on ground motion should be con-sidered when the subways are planned and designed.
文摘To understand the earthquake characteristics in Xinfengjiang (XFJ for short) reservoir area, we collected the small earthquakes occurred in the area from 1961 to 1999. We segmented this 40-year period, parted the research region and calculated the composite fault plane solution of each block, disscussed the effect characteristics of stress field of water pressure using Mohrs stress circle. The final result shows that the main rupture pattern was very different before and after the M = 6.1 main shock, changing from strike slip to normal rupture. The maximum principal stress axes of composite fault plane solutions are characterized by synchronous change with water level.
文摘A numerical model has been developed to simulate the transport and fate of oil spilled at sea. The model combines the transport and fate processes of spilled oil with the random walk technique. Oil movement under the influence of tidal currents, wind driven currents, and turbulent eddies is simulated by the PLUME RW dispersion model developed by HR Wallingford. The weathering processes in the model represent physical and chemical changes of soil slicks with time, and comprise mechanical spreading, dispersion, evaporation and emulsification. Shoreline stranding is determined approximately using a capacity method for different shoreline types. This paper presents details of the model, and describe the results of various sensitivity tests. The model is suitable for oil spill contingency planning.
文摘The acidic wastewater containing manganese and other heavy metal ions came from the plant which produce titanium dioxide in the method of the sulfuric acid digestion was disposed under the processes of the pre\|neutralization with the mineral containing phosphorus and calcium, alkaline precipitation and re\|regulating pH with the raw wastewater. The removal ratio of manganese and ferrous were higher than 99% and 98%, respectively, when the concentration of manganese and ferrous were 46 mg/L and 2000 mg/L. More than 5800 mg/L of SO\+\{2-\}\-4 were neutralized also. The effluent pH was the range between 6 and 9, the concentration of other pollution substances were all very lower even have not discoveried.
文摘Polyferric\|silicate\|sulfate(PFSS),as a new type of coagulant,was prepared by using sodium silicate, sulfuric acid and ferric sulfate as materials.The zeta potential of hydrolyzate of PFSS under different pH values was investigated.The effects of Fe/SiO\-2 molar ratio and dosage of PFSS on turbidity removal were studied. The relation between the optimum coagulation pH range and Fe/SiO\-2 molar ratio was found and the coagulation mechanism of PFSS was discussed.The experimental results showed that Fe/SiO\-2 molar ratio has an effect on the zeta potential of hydrolyzate, the coagulation performance and the optimum coagulation pH range of PFSS and that PFSS gives the best turbidity removal effect when its Fe/SiO\-2 molar ratio was 1.5.
文摘The IC 50 values of 20 nitroaromatics were determined by the activity of ATPase of carp ( Cyprinus carpio ) kidney in vitro, and used to develop the quantitative structure activity relationship (QSAR) with 6 descriptors of 1 X v, Σσ -, I , 1 Ka , E LUMO , log P . A best equation was obtained by multiple regression analysis -log IC 50 =1 306 Σσ -+0 657 I +0 584E LUMO +2 852( r =0 925). Σσ - is the sum of substituent constants. I is the indicator variable. E LUMO is the energy of the lowest unoccupied orbital. Results showed that the Σσ -, I and E LUMO were closely correlated with toxicity of nitroaromatics. Some toxicity mechanisms by nitroaromatics are also discussed in this paper.
文摘The transfer kinetics of phenol between aqueous phase and N,N di(methyl heptyl) acetaminde (N503) in kerosene has been studied using Lewis cell technique. The effects of the factors including the concentrations of phenol in aqueous phase and organic phase, the concentration of N503 in organic phase, the acidity of aqueous phase, the stirring speed and the temperature on the rates of forward and backward extraction of phenol have been examined. The regularity of extraction rate has been obtained. According to experimental results, the rates of both forward and backward extraction of phenol might be controlled by diffusion process. The diffusion step of phenol from aqueous phase to interface for forward extraction and from interface to aqueous phase for backward extraction might be the rate controlling steps.
文摘The novel ways for the filtration improvement of zinc hydroxide sludge precipitated from the zinc\|containing solutions was investigated. It was found that, when the zinc\|containing solutions were added to sodium hydroxide solution, the filtration of the obtained precipitates was improved to some extent, depending on the molar ratios of OH\+-/Zn, in comparison with those obtained by conventional addition of hydroxide solution to zinc\|containing solution, even the ratios were kept the same in these two alkalization methods. The experimental results showed that such an improvement may be contributed to the presence of muddy precipitates formed homogeneously in the sludge. It was suggested that it was zinc\|containing solution that should be added into hydroxide solution, when the zinc was removed from aqueous solution by the precipitation of zinc hydroxides. As a result, the sludge obtained will be filtered and rinsed readily.
