Two biological nitrogen removal processes are compared in the aspect of nitrogen removal, process operation and energy saving. Results show that when the returned sludge ratio is 50% of the inflow rate, the step-feedi...Two biological nitrogen removal processes are compared in the aspect of nitrogen removal, process operation and energy saving. Results show that when the returned sludge ratio is 50% of the inflow rate, the step-feeding process achieves over 80% total nitrogen （TN） removal efficiency, but the TN removal efficiency of the A/O process is only 40%. Moreover, filamentous sludge bulking can be well restrained in the step-feeding process. Given the conditions of a returned sludge ratio of 100% and a nitrifying liquor recycle ratio of 200%, the TN removal efficiency is 78.32% in the A/O process, but the sludge volume index （SVI） value increases to 143 mL/g. In the step-feeding process, the SVI is only 94.4 mL/g when the TN removal efficiency reaches 81. 1%. The step-feeding process has distinct advantages over the A/O process in the aspects of practicability, nitrogen removal and operating stability.展开更多
This paper relates to highly dispersed supported Pd/MWCNTs and Fd/a-Al2O3 catalysts prepared by biological reduction method. The physico-chemical properties and the difference in catalytic activity of Pd catalysts pre...This paper relates to highly dispersed supported Pd/MWCNTs and Fd/a-Al2O3 catalysts prepared by biological reduction method. The physico-chemical properties and the difference in catalytic activity of Pd catalysts prepared by bio- logical reduction method and chemical method, respectively, were investigated using XRD, TEM and specific surface char- acterization methods. The catalytic properties of catalysts were studied through activity evaluation means. The test results showed that the catalysts prepared by biological method were characteristic of small Pd nanoparticle size, good dispersion and low agglomeration, while possessing a high activity and stability in styrene hydrogenation reaction in comparison with catalysts prelgared via the chemical method.展开更多
In order to examine the optimal design and operating parameters in composting of waste activated sludge,a series of experiments were conducted to discuss the optimal operating parameters for aerobic composting of wast...In order to examine the optimal design and operating parameters in composting of waste activated sludge,a series of experiments were conducted to discuss the optimal operating parameters for aerobic composting of waste activated sludge obtained from Vinh Loc Industrial Park that is located in Ho Chi Minh City.The study was done by optimizing the ratios of sludge/inactive fillers and sludge/microbial products to improve the composting efficiency.After 50 days of composting,the composts of all experiment batches met the microorganism-organic fertilizer standards of 10 TCN 526:2002.The study indicated that the highest efficiency decomposition was obtained at the ratio of a sludge/inactive fillers of 1/0.1 and sludge/microbial products of 1/0.05:TOC(Total Organic Carbon)reduced by 20.2%,loss of Nitrogen was trivial(0.53%),the highest temperature reached at 55.5 oC and lasting for 5 days which ensures elimination of pathogens.However,the addition of nitrogen compounds during the composting is necessary to ensure the compost product can meet the nitrogen standard of microorganism-organic fertilizer.展开更多
A series of rotenone O-alkyl oxime derivatives was designed and synthesized. Their structures were confirmed by elemental analyses, Fourier transform infrared（FTIR） and 1H NMR spectral studies, and the typical cryst...A series of rotenone O-alkyl oxime derivatives was designed and synthesized. Their structures were confirmed by elemental analyses, Fourier transform infrared（FTIR） and 1H NMR spectral studies, and the typical crystal structure of rotenone O-ethyl oxime（3b） was determined by X-ray diffraction. The preliminary biological activities of the new compounds were evaluated. The results of bioassays indicate that the title compounds exhibit moderate insecticidal and bactericidal activities. Among the synthesized compounds, compound 3q exhibited 90.0% mortality against M. separata at 1000 μg/mL. Compounds 3b and 3g exhibited both 90.0% inhibition rate against R. solani at 500 μg/mL, respectively.展开更多
Microstructure and interracial reactions of Al2O3 joints brazed with Al2O3-particulate-contained composite Ag-Cu-Ti filler material were researched by scanning electron microscopy （SEM）, electron probe microscopy an...Microstructure and interracial reactions of Al2O3 joints brazed with Al2O3-particulate-contained composite Ag-Cu-Ti filler material were researched by scanning electron microscopy （SEM）, electron probe microscopy analysis （EPMA）, energy dispersive spectroscopy （EDS） and X-ray diffraction （XRD）. The interracial reaction layer thickness of joints brazed with conventional active filler metal and active composite filler materials with different volume fraction of Al2O3 particulate was also studied. The experimental results indicated although there were Al2O3 particulates added into active filler metals, the time dependence of interracial layer growth of joints brazed with active composite filler material is t^1/2 as described by Fickian law as the joints brazed with conventional active filler metal.展开更多
基金The Project of Scientific Research Base and Scientific Innovation Platform of Beijing Municipal Education Commission (No.PXM2008-014204-050843)the Project of Beijing Science and Technology Committee (No.D07050601500000)+1 种基金the Knowledge Innovation Program of the Chinese Academy of Sciences (No.RCEES-QN-200706)the Special Funds for Young Scholars of RCEES,CAS.
文摘Two biological nitrogen removal processes are compared in the aspect of nitrogen removal, process operation and energy saving. Results show that when the returned sludge ratio is 50% of the inflow rate, the step-feeding process achieves over 80% total nitrogen （TN） removal efficiency, but the TN removal efficiency of the A/O process is only 40%. Moreover, filamentous sludge bulking can be well restrained in the step-feeding process. Given the conditions of a returned sludge ratio of 100% and a nitrifying liquor recycle ratio of 200%, the TN removal efficiency is 78.32% in the A/O process, but the sludge volume index （SVI） value increases to 143 mL/g. In the step-feeding process, the SVI is only 94.4 mL/g when the TN removal efficiency reaches 81. 1%. The step-feeding process has distinct advantages over the A/O process in the aspects of practicability, nitrogen removal and operating stability.
文摘This paper relates to highly dispersed supported Pd/MWCNTs and Fd/a-Al2O3 catalysts prepared by biological reduction method. The physico-chemical properties and the difference in catalytic activity of Pd catalysts prepared by bio- logical reduction method and chemical method, respectively, were investigated using XRD, TEM and specific surface char- acterization methods. The catalytic properties of catalysts were studied through activity evaluation means. The test results showed that the catalysts prepared by biological method were characteristic of small Pd nanoparticle size, good dispersion and low agglomeration, while possessing a high activity and stability in styrene hydrogenation reaction in comparison with catalysts prelgared via the chemical method.
文摘In order to examine the optimal design and operating parameters in composting of waste activated sludge,a series of experiments were conducted to discuss the optimal operating parameters for aerobic composting of waste activated sludge obtained from Vinh Loc Industrial Park that is located in Ho Chi Minh City.The study was done by optimizing the ratios of sludge/inactive fillers and sludge/microbial products to improve the composting efficiency.After 50 days of composting,the composts of all experiment batches met the microorganism-organic fertilizer standards of 10 TCN 526:2002.The study indicated that the highest efficiency decomposition was obtained at the ratio of a sludge/inactive fillers of 1/0.1 and sludge/microbial products of 1/0.05:TOC(Total Organic Carbon)reduced by 20.2%,loss of Nitrogen was trivial(0.53%),the highest temperature reached at 55.5 oC and lasting for 5 days which ensures elimination of pathogens.However,the addition of nitrogen compounds during the composting is necessary to ensure the compost product can meet the nitrogen standard of microorganism-organic fertilizer.
基金Supported by the National Science and Technology Pillar Program of China(No.2011BAE06B01)
文摘A series of rotenone O-alkyl oxime derivatives was designed and synthesized. Their structures were confirmed by elemental analyses, Fourier transform infrared（FTIR） and 1H NMR spectral studies, and the typical crystal structure of rotenone O-ethyl oxime（3b） was determined by X-ray diffraction. The preliminary biological activities of the new compounds were evaluated. The results of bioassays indicate that the title compounds exhibit moderate insecticidal and bactericidal activities. Among the synthesized compounds, compound 3q exhibited 90.0% mortality against M. separata at 1000 μg/mL. Compounds 3b and 3g exhibited both 90.0% inhibition rate against R. solani at 500 μg/mL, respectively.
基金the National Natural Science Foundation of China(Grant No.50075019) the Visiting Scholar Foundation of Key Lab.in University of China
文摘Microstructure and interracial reactions of Al2O3 joints brazed with Al2O3-particulate-contained composite Ag-Cu-Ti filler material were researched by scanning electron microscopy （SEM）, electron probe microscopy analysis （EPMA）, energy dispersive spectroscopy （EDS） and X-ray diffraction （XRD）. The interracial reaction layer thickness of joints brazed with conventional active filler metal and active composite filler materials with different volume fraction of Al2O3 particulate was also studied. The experimental results indicated although there were Al2O3 particulates added into active filler metals, the time dependence of interracial layer growth of joints brazed with active composite filler material is t^1/2 as described by Fickian law as the joints brazed with conventional active filler metal.
