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1.
Water Sci Technol ; 66(5): 1022-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22797230

RESUMO

Construction solid waste (CSW), an inescapable by-product of the construction and demolition process, was used as main substrate in a four-stage vertical subsurface flow constructed wetland system to improve phosphorus P removal from domestic wastewater. A 'tidal flow' operation was also employed in the treatment system. Under a hydraulic loading rate (HLR) of 0.76 m3/m2 d for 1st and 3rd stage and HLR of 0.04 m3/m2 d for 2nd and 4th stage of the constructed wetland system respectively and tidal flow operation strategy, average removal efficiencies of 99.4% for P, 95.4% for ammoniacal-nitrogen, 56.5% for total nitrogen and 84.5% for total chemical oxygen demand were achieved during the operation period. The CSW-based constructed wetland system presents excellent P removal performance. The adoption of tidal flow strategy creates the aerobic/anoxic condition intermittently in the treatment system. This can achieve better oxygen transfer and hence lead to more complete nitrification and organic matter removal and enhanced denitrification. Overall, the CSW-based tidal flow constructed wetland system holds great promise for enabling high rate removal of P, ammoniacal-nitrogen and organic matter from domestic wastewater, and transforms CSW from a waste into a useful material.


Assuntos
Carbono , Materiais de Construção , Nitrogênio , Fósforo , Eliminação de Resíduos Líquidos/métodos , Áreas Alagadas , Eliminação de Resíduos/métodos , Fatores de Tempo , Poluentes Químicos da Água , Purificação da Água
2.
Water Sci Technol ; 63(10): 2367-73, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21977662

RESUMO

This study examined a novel reuse of alum sludge, an inescapable by-product of drinking water treatment process when aluminium salt is added as a coagulant, as the main medium in a laboratory-scale multi-stage constructed wetland (CW) system for reject water treatment. Such reject water is a main concern in municipal wastewater treatment plant (MWWTP) for increasing the organic and nutrient loading. A 'tidal flow' strategy was employed to enhance the wetland aeration to stimulate organic matters (OM) and ammoniacal-nitrogen (N) oxidation while the 'step feed' operation was adopted to supply the necessary amount of carbon source for denitrification. The results reveal that alum sludge acting as P adsorbent can secure the P removal. Meanwhile, high removals of N and OM can also be obtained due to the active bacteria growth on the alum sludge surface. The results show that average removal efficiencies of 65.4 +/- 12.3% for chemical oxygen demand (COD), 67.8 +/- 9.2% for five-day biochemical oxygen demand (BOD5), 33.6 +/- 17.0% for N and 99.5 +/- 0.49% for P can be achieved over a period of 190 days. This indicates that novel reuse of alum sludge as medium in CW system can provide a promising approach for reject water treatment. Therefore, it will significantly reduce the amount of pollutant feedback through reject water recycling in a MWWTP.


Assuntos
Compostos de Alumínio/química , Movimentos da Água , Purificação da Água , Áreas Alagadas , Resíduos Industriais , Compostos Orgânicos/isolamento & purificação , Fósforo/isolamento & purificação , Compostos de Amônio Quaternário/isolamento & purificação
3.
Artigo em Inglês | MEDLINE | ID: mdl-21644153

RESUMO

This study was conducted to examine the possibility of using construction solid waste (CSW), an inevitable by-product of the construction and demolition process, as the main substrate in a laboratory scale multi-stage constructed wetland system (CWs) to improve phosphorus (P) removal from secondary sewage effluent. A tidal-flow operation strategy was employed to enhance the wetland aeration. This will stimulate aerobic biological processes and benefit the organic pollutants decomposition and nitrification process for ammoniacal-nitrogen (NH(+)(4)-N) removal. The results showed that the average P concentration in the secondary sewage effluent was reduced from 1.90 mg-P/L to 0.04 mg-P/L. CSW presents excellent P removal performance. The average NH(+)(4)-N concentration was reduced from 9.94 mg-N/L to 1.0 mg-N/L through nitrification in the system. The concentration of resultant nitrite and nitrate in the effluent of the CSW based CWs ranged from 0.1 to 2.4 mg-N/L and 0.01 to 0.8 mg-N/L, respectively. The outcome of this study has shown that CSW can be successfully used to act as main substrate in CWs. The application of CSW based CWs on improving N and P removals from secondary sewage effluent presents a win-win scenario. Such the reuse of CSW will benefit both the CSW disposal and nutrient control from wastewater. More significantly, such the application can transfer the CSW from a 'waste' to 'useful' material and can ease the pressure of construction waste solid management. Meanwhile, the final effluent from the CSW-based CWs can be used as non-potable water source in landscape irrigation, agriculture and industrial process.


Assuntos
Materiais de Construção , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Áreas Alagadas , Aerobiose , Amônia/análise , Amônia/metabolismo , Carvão Mineral , Recuperação e Remediação Ambiental , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Nitrogênio/metabolismo , Fósforo/análise , Fósforo/metabolismo , Esgotos/microbiologia , Poluentes Químicos da Água/metabolismo
4.
Anal Biochem ; 273(2): 298-304, 1999 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-10469501

RESUMO

A direct UV-VIS spectrophotometric assay has been developed for peptide deformylase. This assay employs a novel class of peptide mimetics as deformylase substrates which, upon enzymatic removal of the N-terminal formyl group, rapidly release free thiols. The released thiols are quantitated using Ellman's reagent. A variety of peptide analogues that contain beta-thiaphenylalanine or beta-thiamethionine as the N-terminal residue were synthesized and found to be excellent substrates of the peptide deformylase from Escherichia coli (k(cat)/K(M) = 6.9 x 10(5) M(-1) s(-1) for the most reactive substrate). The deformylase reaction is conveniently monitored on a UV-VIS spectrophotometer in a continuous fashion. The versatility of the assay has been demonstrated by its application to kinetic characterization of the deformylase, pH profile studies, and enzyme inhibition assays. The assay can also be performed in an end-point fashion. The results demonstrate that this assay is a simple, highly sensitive, and rapid method to study kinetic properties of deformylases without the use of any coupling enzymes.


Assuntos
Amidoidrolases , Aminopeptidases/análise , Espectrofotometria Ultravioleta/métodos , Espectrofotometria/métodos , Aminopeptidases/antagonistas & inibidores , Aminopeptidases/metabolismo , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/farmacologia , Escherichia coli/enzimologia , Concentração de Íons de Hidrogênio , Cinética , Oligopeptídeos/síntese química , Oligopeptídeos/química , Especificidade por Substrato
5.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 15(11): 646-8, 1995 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-8732146

RESUMO

The authors treated 40 cases of shoulder-hand syndrome of apoplexy hemiplegia with electro-acupuncture (EA) and filiform needle acupuncture (FNA) respectively. The results showed that EA had better results in treating hand back swelling, hand skin temperature elevating and the bending finger caused pain than that with FNA (P < 0.05). The finger joint and shoulder joint improvement (the functional scoring increased for 3 points or more) in EA was also better than that of FNA (P < 0.05). The total marked effective rate was higher in EA group (75%) than that in FNA (50%), P < 0.05). It suggested that EA produced rhythmic muscle contraction which had a "shoulder-hand pump" like action, and is significant in eliminating hand back swelling and preventing atrophy of hand muscles.


Assuntos
Terapia por Acupuntura , Transtornos Cerebrovasculares/complicações , Eletroacupuntura , Hemiplegia/terapia , Distrofia Simpática Reflexa/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemiplegia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Distrofia Simpática Reflexa/etiologia
6.
Zhong Xi Yi Jie He Za Zhi ; 11(5): 263-4, 259, 1991 May.
Artigo em Chinês | MEDLINE | ID: mdl-1831734

RESUMO

The relationship between 68 cases of thromboxane B2(TXB2), 6-keto-prostaglandin F1 alpha (6-K-PGF1 alpha), beta-thromboglobulin (beta TG), platelet factor 4 (PF4), protein C antigen (PC:Ag), total-proteins (T-Ps) with coronary heart disease (CHD) based on TCM syndrome differentiation were studied. 45 cases of male, 23 cases of female, they were divided into 30 cases of blood stasis group and 38 cases of Qi syndrome group. 39 healthy subjects of same age and sex were chosen as the control group. The results were as follows: The TXB2, beta TG, PF4 in CHD were higher than those of control. 6-K-PGF1 alpha was lower (P less than 0.05, P less than 0.01) respectively. The TXB2 in blood stasis was significantly higher than that of Qi syndrome while the 6-K-PGF1 alpha in Qi Syndrome was significantly lower than that of blood stasis syndrome (P less than 0.01). The PC:Ag, T-Ps in CHD were higher than those of the control. The PC:Ag in blood stasis was lower and was higher in Qi syndrome (P less than 0.01). It showed that microthrombosis formed in blood stasis group caused blood flow slowly, while coronary-pathy and/or coronary spasm were the major pathologic change in Qi syndrome. Elevated PC:Ag, T-Ps in Qi syndrome showed that there were complementary action to hypercoagulation in Qi syndrome to eliminate coagulation factor to prevent coagulation happening and stimulation of fibrinolysin activator, promoting fibrinogenolysis.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
6-Cetoprostaglandina F1 alfa/sangue , Plaquetas/fisiologia , Doença das Coronárias/sangue , Medicina Tradicional Chinesa , Proteína C/imunologia , Adulto , Idoso , Angina Pectoris/sangue , Antígenos/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fator Plaquetário 4/análise , beta-Tromboglobulina/análise
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