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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(3): 784-8, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21595240

RESUMO

The dissolved organic matter (DOM) of acrylonitrile-butadiene-styrene (ABS) resin wastewater was qualitatively analysed by gas chromatography with mass spectrometry(GC-MS), Fourier transform infrared spectrometer(FTIR) and three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy. The detected results shows that the GC-MS qualitatively analysed 21 dissolved organic pollutants, such as acetophenone, styrene, alpha, alpha-dimethyl-benzenemethanol, 3,3'oxybis-propanenitrile, 3, 3'-iminobis-propanenitrile, 3,3'-thiobis-propanenitrile, 3-(dimethylamino)-propanenitrile and 2-propenenitrile. The results of Fourier transform infrared spectrometer (FTIR) and three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy could examine and certify the accuracy and integrity for the qualitative analysis of GC-MS. The results of this study provides an important guiding role for the development of wastewater treatment process.

2.
Water Sci Technol ; 54(9): 35-43, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17163040

RESUMO

To find an efficient biological method to solubilize waste activated sludge (WAS) from the biological wastewater treatment process, several strains of thermophilic bacteria capable of solubilizing WAS were isolated from sewage sludge compost. The culture supernatants of the isolates were able to lyse vegetable bacterial cells and the lytic activity mainly came from the exoenzyme produced by the isolates. The culture supernatants of the different isolates showed different lysis characteristics. The factors affecting bacterial cell lysis were investigated using E. coli as a model bacterium. The E. coli cells were lysed easily at higher temperature (60 degrees C or 70 degrees C) while little lytic activity by the supernatants of isolates was observed at lower temperature (50 degrees C). The level of pH also had great influence on the lysis of E. coli cells. The E. coli cells in the early stationary growth phase were easier to lyse than those in the late stationary growth phase or death phase.


Assuntos
Bactérias/isolamento & purificação , Bacteriólise/fisiologia , Microbiologia Ambiental , Esgotos/microbiologia , Gerenciamento de Resíduos/métodos , Bactérias/citologia , Biodegradação Ambiental , Escherichia coli/citologia , Escherichia coli/isolamento & purificação , Temperatura Alta , Controle de Infecções , Modelos Biológicos , Solubilidade , Fatores de Tempo
3.
Lancet Infect Dis ; 15(2): 196-203, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25539588

RESUMO

BACKGROUND: Human babesiosis is an emerging zoonosis. "Babesia venatorum" has been identified in only four asplenic men and a child so far. We aimed to describe the epidemiological, clinical, and laboratory characteristics of a series of cases with "B venatorum" infection identified in a sentinel hospital in China. METHODS: We recruited participants with a recent tick bite at Mudanjiang Forestry Central Hospital, Heilongjiang province, China. Cases were diagnosed through PCR followed by sequencing, microscopic identification, or isolation by animal inoculation, or both. FINDINGS: 48 individuals (30 women or girls; median age 45 years, range 7 months to 75 years) with "B venatorum" infection were identified. 32 of these individuals were confirmed cases and 16 were probable cases. None of the 48 cases had received a blood transfusion or had a splenectomy. Geographically, cases were distributed diffusely throughout the hospital catchment area. Of the 32 confirmed cases, 21 (66%) presented with a fever, 13 (41%) with a headache, 12 (38%) with myalgia or arthralgia, and three (9%) with chills. 14 (44%) patients had fatigue, eight (25%) had dizziness, and eight (25%) had hypersomnia. Six (19%) patients had an erythematous non-pruritic rash around the tick-bite site and two (6%) had lymphadenopathy. Seven (22%) and four (13%) patients had anaemia and thrombocytopenia, respectively, and seven (50%) of 14 patients with confirmed infection had increased hepatic transaminase concentrations. In the confirmed cases, concentrations of intercellular adhesion molecule 3 (p<0·001), P-selectin (p<0·05), and platelet endothelial cell adhesion molecule 1 (p<0·001) were significantly reduced, whereas tumour necrosis factor α (p<0·01) and vascular cell adhesion molecule 1 (p<0·001) were significantly increased. INTERPRETATION: "B venatorum" infection should be included in the differential diagnosis of patients with a tick-exposure history in areas where this pathogen has previously been identified in ticks or people. FUNDING: Natural Science Foundation of China and Mega-Project for Infectious Diseases.


Assuntos
Babesia/isolamento & purificação , Babesiose/epidemiologia , Babesiose/patologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/patologia , Adolescente , Adulto , Idoso , Animais , Babesiose/diagnóstico , Babesiose/parasitologia , Criança , Pré-Escolar , China/epidemiologia , Técnicas de Laboratório Clínico , Feminino , Humanos , Lactente , Masculino , Microscopia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Picadas de Carrapatos/complicações , Doenças Transmitidas por Carrapatos/diagnóstico , Doenças Transmitidas por Carrapatos/parasitologia , Adulto Jovem
4.
Lancet Infect Dis ; 15(6): 663-70, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25833289

RESUMO

BACKGROUND: Anaplasma phagocytophilum and Anaplasma ovis cause human infections. We investigated the potential for human pathogenicity of a newly discovered Anaplasma species infecting goats in China. METHODS: We collected blood samples from patients with a history of tick bite in the preceding 2 months at Mudanjiang Forestry Central Hospital of Heilongjiang Province from May 1, to June 10, 2014, to detect the novel Anaplasma species by PCR. We inoculated positive samples into cell cultures. We characterised the isolated pathogen by morphological and phylogenetic analyses. We tested serum antibodies by indirect immunofluorescence assay. FINDINGS: 28 (6%) of 477 patients assessed were infected with the novel Anaplasma species according to PCR and sequencing. We isolated the pathogen in vitro from three patients. Phylogenetic analyses of rrs, gltA, groEL, msp2, and msp4 showed that the pathogen was distinct from all known Anaplasma species. We provisionally nominate it "Anaplasma capra". 22 (92%) of 24 patients with data available had seroconversion or a four-fold increase in antibody titres. All 28 patients developed non-specific febrile manifestations, including fever in 23 (82%), headache in 14 (50%), malaise in 13 (46%), dizziness in nine (32%), myalgia in four (14%), and chills in four (14%). Additionally, ten (36%) of 28 patients had rash or eschar, eight (29%) had lymphadenopathy, eight (29%) had gastrointestinal symptoms, and three (11%) had stiff neck. Five patients were admitted to hospital because of severe disease. Six (35%) of 17 patients with data available had high hepatic aminotransferase concentrations. INTERPRETATION: The emergence of "A capra" as a cause of human disease suggests that individuals living in or travelling to endemic regions in northern China should take precautions to reduce their risk of exposure to this novel tick-borne pathogen. FUNDING: Natural Science Foundation of China and the US National Institutes of Health.


Assuntos
Anaplasma/classificação , Anaplasma/isolamento & purificação , Ehrlichiose/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Adolescente , Adulto , Idoso , Anaplasma/genética , Animais , Técnicas de Cultura de Células , Criança , China/epidemiologia , Monitoramento Epidemiológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Adulto Jovem
5.
Huan Jing Ke Xue ; 33(9): 3167-71, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23243875

RESUMO

A multi-stage microaerobic biological fluidized bed reactor was used for the pretreatment of synthetic wastewater containing high concentration of acrylic acid (AA). The effect of influent load was investigated and the intermediate products of acrylic acid degradation were analyzed. It indicated that the removal rate of AA was above 95% with effluent acrylic acid less than 150 mg x L(-1) and COD removal rate of 15%-30%, under the following conditions: hydraulic retention time of 12 h, waste water temperature of 25 degrees C, influent acrylic acid concentration of 3 000-9 000 mg x L(-1), volume load of 6.0-18.0 kg x (m3 x d)(-1). The main intermediate products of acrylic acid degradation were acetic and propionic acids. The multi-stage microaerobic biological fluidized bed reactor can transform each 1.00 mol acrylic acid into 0.22 mol acetic acid and 0.36 mol propionic acid, and achieve the pretreatment of acrylic acid wastewater at high loads.


Assuntos
Acrilatos/isolamento & purificação , Reatores Biológicos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Acrilatos/metabolismo , Aerobiose , Biodegradação Ambiental
6.
Huan Jing Ke Xue ; 32(5): 1382-7, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21780595

RESUMO

The butyl-acrylate-production wastewater was treated by a three-phase biological fluidized bed reactor. The influences of acrylic acid concentrations, p-toluenesulfonic acid concentrations, volumic load and hydraulic retention time on pollutants removal efficiencies were investigated. It was indicated that the reactor was suitable for the treatment of butyl-acrylate-production wastewater at a high loading rate. Acrylic acid of 100 mg/L or p-toluenesulfonic acid of 50 mg/L in the influent can inhibit the unacclimated microorganisms in the fluidized bed reactor. The inhibition effects were eliminated after an acclimation of two weeks. Acrylic acid and p-toluenesulfonic acid could be removed completely at COD loading rates up to 11.56-13.56 kg/(m3 x d). The effluent COD could satisfy the demand of Class II in Chinese Integrated Wastewater Discharge Standard (GB 8978-1996) at COD loading rates up to 8.86 kg/(m3 x d) when influent COD concentration is below 2000 mg/L. When the influent COD concentration was increased to 9550-11,800 mg/L(acrylic acid of 6244 mg/L and p-toluenesulfonic acid of 1000 mg/L), the effluent COD was 271-360 mg/L, which satisfied the demand of Class III in Chinese Integrated Wastewater Discharge Standard (GB 8978-1996) at COD loading rates of 7.96-9.83 kg/(m3 x d).


Assuntos
Acrilatos/isolamento & purificação , Reatores Biológicos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Biodegradação Ambiental
7.
Huan Jing Ke Xue ; 32(4): 1055-9, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21717747

RESUMO

Wastewater from the condensation and drying section of acrylonitrile-butadiene-styrene (ABS) resin plant was pretreated by the microelectrolysis, and the effect of the influent pH value on the pollution removal efficiency of the microelectrolysis was mainly studied. In order to study the electrochemical action of the microelectrolysis for the degradation of toxic refractory organic pollutants, two control experiments of activated carbon and iron were set up. The results showed that the TOC removal efficiencies were all fluctuated between 40% and 60% under the condition of different influent pH values. The microelectrolysis can decompose and transform the toxic refractory organic pollutants and increase the BOD5/COD ratio from 0.32 to 0.60, which increased the biodegradability of ABS resin wastewater significantly. When the pH value of influent was 4.0, the BOD5/COD ratio of effluent reached 0.71. The result of UV-vis spectra indicates that the removal efficiency of the organic nitrile was the highest with influent pH was 4.0. Therefore, the best influent pH value of microelectrolysis was 4.0.


Assuntos
Resinas Acrílicas , Butadienos , Eletrólise/métodos , Resíduos Industriais , Poliestirenos , Eliminação de Resíduos Líquidos/métodos , Acrilonitrila/química , Butadienos/química , Eletroquímica/métodos , Microeletrodos , Estireno/química
8.
Huan Jing Ke Xue ; 32(10): 2956-60, 2011 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-22279908

RESUMO

High-concentration acrylate wastewater was treated by an electrocatalytic reduction process. The effects of the cation exchange membrane (CEM) and cathode materials on acrylate reduction were investigated. It indicated that the acrylate could be reduced to propionate acid efficiently by the electrocatalytic reduction process. The addition of CEM to separator with the cathode and anode could significantly improve current efficiency. The cathode materials had significant effect on the reduction of acrylate. The current efficiency by Pd/Nickel foam, was greater than 90%, while those by nickel foam, the carbon fibers and the stainless steel decreased successively. Toxicity of the wastewater decreased considerably and methane production rate in the biochemical methane potential (BMP) test increased greatly after the electrocatalytic reduction process.


Assuntos
Acrilatos/isolamento & purificação , Técnicas Eletroquímicas/métodos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Acrilatos/química , Catálise , Metano/análise , Oxirredução , Propionatos/análise , Propionatos/química
9.
Huan Jing Ke Xue ; 28(9): 2106-11, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17990566

RESUMO

One spore-forming thermophilic bacterial strain SY-14, isolated from sewage sludge compost, showed significant capability to lyse bacterial cells. The strain was identified as Geobacillus sp. based on morphological characteristics and homology identification of 16S rDNA sequence. The optimal temperature and pH for growth were about 60 degrees C and pH 6.0-7.0 respectively. The culture supernatant of SY-14 showed lytic activity against both intact and thermal inactivated bacterial cells, and the cell lysis percentages at 6 hours were 70% and 85% respectively. The lytic activity of the culture supernatant decreased significantly after heat treatment, which inferred the lytic activity mainly derived from extracellular lytic enzymes of SY-14. The lytic activity of the culture supernatants of SY-14 increased significantly during the log phase in the batch culture process, and then decreased quickly after the maximum activity was reached. The culture supernatant of SY-14 showed lytic activity against all the five tested Gram-negative strains and some tested Gram-positive strains.


Assuntos
Bacteriólise/fisiologia , Geobacter/metabolismo , Esgotos/microbiologia , Bacteriólise/efeitos dos fármacos , Biodegradação Ambiental , Meios de Cultivo Condicionados/farmacologia , Geobacter/genética , Geobacter/isolamento & purificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Temperatura Alta , Viabilidade Microbiana/efeitos dos fármacos , RNA Ribossômico 16S/genética , Fatores de Tempo
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