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ABSTRACT: To investigate the performances of phosphorus removal in a sequencing batch reactor (SBR) with single-stage oxic process using synthetical wastewater, glucose (R1) and acetate (R2) were fed to two SBRs as the sole carbon source, respectively. The operation run mode was determined to be: influent --> aeration (4 h) --> settling (8 h) --> effluent. The results showed that the performance of phosphorus removal in R1 was higher than that in R2 after steady-operation. Total phosphorus (TP) removed per MLVSS in R1 and R2 were 7.2-7.7 and 3.8-4.6 mg x g(-1) during aeration, respectively, but the rate of phosphorus release at the two reactors were 3.6-3.8 and 2.7-3.1 mg x g(-1) during the idle zone, respectively. The energy storage of poly-beta-hydroxyalkanoates (PHA) was constant nearly in R1 during the whole period, but glycogen was accumulated to the maximum value at 30 minutes of aeration, and then was decreased to the initial level. However in R2, PHA and glycogen were both accumulated at about 45 minutes of aeration. This phenomenon suggested that glycogen is the main energy source for metabolism during aerobic period in R1, and the main energy resource come from the decomposition of PHA and the hydrolysis of glycogen in R2. The facts showed that glycogen could replace PHAs to supply energy for phosphate uptake and polyphosphate accumulation in such a single-stage oxic process. Since glycogen accumulated in R1 was more than that in R2, the efficiency of phosphorus removal in R1 was higher than that in R2.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 01/2010; 31(1):124-8.
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Advanced Synthesis & Catalysis 11/2009; 351(18):3096 - 3100. · 6.05 Impact Factor
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ABSTRACT: A mild method for selective synthesis of o-acylbenzylphosphonates has been developed by the reactions of arynes with beta-ketophosphonates. In the presence of CsF and THF, the carbon-carbon sigma-bonds of 2-oxopropylphosphonates were selectively cleaved and added to arynes providing the corresponding 2-acylbenzylphosphonates in moderate to good yields.
The Journal of Organic Chemistry 09/2009; 74(15):5691-4. · 4.45 Impact Factor
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ABSTRACT: According to nitrogen-containing wastewater, effects of salinity variation on nitrification and denitrification in internal circulation sequencing batch biofilm reactor (SBBR) and sequencing batch reactor (SBR), and the process of recovery as decreased salinity were investigated. The results show that nitrosation process is effected in internal circulation SBBR and SBR as the increase of salinity, and as the salinity is less than 1.0 x 10(4) mg x L(-1), the speed of ammonia-oxidize is quicker in the SBR than in the SBBR, but the state is opposite as the salinity beyond 1.5 x 10(4) mg x L(-1). As the salinity increased to 4.0 x 10(4) mg x L(-1), the process of ammonia-oxidize was restrained strongly both in SBBR and SBR. The nitrite accumulation is attained continually as the salinity at 1.5 x 10(4) mg x L(-10 and 2.5 x 10(4) mg x L(-1) in the SBBR and SBR respectively. In the SBBR, the removal rate of TN was about 60% as the salinity was less than 1.5 x 10(4) mg x L(-1), and the SND was restrained strongly as the salinity beyond 3.0 x 10(4) mg x L(-1).
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 09/2009; 30(9):2603-8.
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ABSTRACT: Palladium-catalyzed cocyclotrimerization of allenes with arynes has been developed for selectively synthesizing phenanthrenes. In the presence of [(allyl)PdCl](2) and P(o-tol)(3), a variety of allenes, including internal and terminal allenes, underwent the cocyclotrimerization with arynes to afford the corresponding phenanthrenes in moderate to good yields. The results showed the selectivity of the reaction based on allenes.
The Journal of Organic Chemistry 05/2009; 74(8):3199-202. · 4.45 Impact Factor
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ABSTRACT: A single-chamber and membrane-less microbial fuel cells were successfully started up using anaerobic sludge as inoculums without any chemical substance for 20 d. The electricity generation of the microbial fuel cell using surplus sludge as fuel and the change of substrate were investigated. The results showed that the obtained maximum voltage and power density were 495 mV and 44 mW x m(-2) (fixed 1,000 Omega), and the internal resistance was about 300 Omega during steady state. In a cycle, the removal efficiency of SS and VSS were 27.3% and 28.7%, pH was 6.5-8.0. In addition, the COD increased from 617 mg x L(-1) to 1,150 mg x L(-1) and decreased afterwards with time. The change of glucose was similar to that of COD, glucose increased from 47 mg x L(-1) to 60 mg x L(-1) and decreased afterwards with time. Consequently, the microbial fuel cell can transform chemical energy of surplus sludge into the cleanest electrical energy, and it provides a new way of sludge recycling.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 05/2009; 30(4):1227-31.
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ABSTRACT: A novel and selective protocol for the synthesis of 1-allyl-2-ethynylbenzenes has been developed by palladium-catalyzed decarboxylative coupling of allylic alkynoates with arynes. This new route allows for both sp-sp(2) and sp(2)-sp(3) couplings of allylic alkynoates with arynes in one pot involving a decarboxylation process.
Organic Letters 05/2009; 11(11):2309-12. · 5.86 Impact Factor
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Dong-bo Wang,
Xiao-ming Li,
Qi Yang,
Wei Zheng,
Zong-yao Liu, Yi-lin Liu,
Jian-bin Cao,
Xiu Yue,
Ting-ting Shen,
Guang-ming Zeng,
Jiu-hua Deng
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ABSTRACT: To investigate the possible biochemical metabolisms for excess phosphate uptake in a sequencing batch reactor (SBR) with single-stage oxic process, which was reported using glucose as the sole carbon source previously, glucose and acetate were fed to two SBRs as the sole carbon source, respectively. The changes of polyhydroxyalkanoates (PHAs), glycogen and the removal of phosphorus were compared between two SBRs. It was observed that the phosphorus removal efficiency was 91.8-94.4% with glucose, and 23.3-28.5% with acetate, although the former showed much lower accumulations/transformations of PHAs. Instead, the former showed a much higher transformation of glycogen. The facts suggested that glycogen could replace PHAs to supply energy for phosphate uptake under the single-stage oxic condition. Furthermore, the possible biochemical metabolisms were proposed to describe the relation between phosphate uptake and energy storages formations under such a single-stage oxic process. Such a process may serve as a prototype for the development of alternative biological and chemical options for phosphate removal from wastewaters.
Bioresource technology 05/2009; 100(17):4005-11. · 4.25 Impact Factor
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ABSTRACT: The performance of phosphorus removal with a sequencing batch reactor was investigated by simulated municipal wastewater. The experimental results showed that phosphorus removal could be achieved in sequencing batch reactor without anaerobic phase, which was conventionally considered as a key phase for phosphorus removal. Phosphorus concentration in the effluent was 1.0 mg x L(-1) below after 4 h aeration, during which pH was 7.0 +/- 0.2. Which indicated the removal rate of phosphorus was above 90% when the COD and phosphorus concentrationof influent were about 400 mg x L(-1), 15-20 mg x L(-1), respectively. Intracellular storage of poly-phosphate (poly-P) was increasing in the aeration after decreasing in first hour aeration (the content of poly-P was 83.034 mg x g(-1) at the beginning of aerobic phase, 79.980 mg x g(-1) in first aeration and 83.086 mg x g(-1) in end), but the energy storage poly-beta-hydroxyalkanoates (PHA) was constant nearly and the content was very low (PHA concentration was about 5 mg x L(-1)). The researches indicated that phosphate could be transformed to poly-P by poly-phosphate-accumulating organisms without anaerobic zone and PHA, biological phosphorus removal was obtained by removing sludge with rich phosphorus, and this phenomenon could not be explained by conventional theory.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 08/2008; 29(7):1867-73.
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ABSTRACT: A mild and general cycloaddition of arynes with iodonium ylides protocol has been developed for the synthesis of benzofurans. In the presence of CsF, ortho-silyl aryltriflates were reacted with iodonium ylides smoothly at room temperature in moderate to good yields.
Organic Letters 05/2008; 10(8):1525-8. · 5.86 Impact Factor