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1.
Huan Jing Ke Xue ; 44(12): 6801-6810, 2023 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-38098405

RESUMO

Sludge biochar(BC), which was prepared by the pyrolysis of waste-activated sludge at 450℃, was applied for peroxymonosulfate(PMS) activation to construct a BC/PMS system for ciprofloxacin(CIP) degradation. The physical and chemical properties of BC were studied using scanning electron microscopy(SEM), an energy dispersive spectrometer(EDS), a Fourier transform infrared spectrometer(FTIR), X-ray diffraction(XRD), a Zeta potential analyzer, and electron paramagnetic resonance spectroscopy(EPR). The effects of BC dosage, PMS dosage, initial pH value, and inorganic anions on CIP removal in the BC/PMS system were investigated. Further, the degradation mechanism of the BC/PMS system was speculated through the free radical quenching experiment and X-ray photoelectron spectroscopy(XPS) analysis. The results showed that the CIP degradation rate was 49.09% at a BC dosage of 1.0 g·L-1, PMS of 3.0 mmol·L-1, CIP of 20 mg·L-1, and pH of 6.0 in 120 min. SO42- and NO3- had no obvious effect on the removal of CIP in the BC/PMS system, whereas HCO3- and Cl-could inhibit CIP degradation significantly. The CIP removal in the BC/PMS system was attributed to the common function of the radical pathway dominated by ·OH and SO4-· and the non-radical pathway dominated by 1O2. The CIP degradation pathway mainly included piperazine ring opening and hydroxylation reaction.


Assuntos
Esgotos , Poluentes Químicos da Água , Ciprofloxacina , Poluentes Químicos da Água/análise , Peróxidos/química
2.
Chemosphere ; 325: 138387, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36914007

RESUMO

A novel and recyclable composite material, Fe3O4/N co-doped sludge biochar (FNBC), was developed from original sludge biochar (BC) and found to have excellent stability and superior catalytic capacity during the ciprofloxacin (CIP) degradation under the action of peroxymonosulfate (PMS). In the FNBC/PMS system, an approximately complete removal of CIP was achieved within 60 min under the condition of 1.0 g/L FNBC, 3.0 mM PMS, and 20 mg/L CIP, which was about 2.08 times of that in BC/PMS system (48.01%). Besides, FNBC/PMS system could effectively remove CIP under the influence of wide pH (2.0-10.0) or inorganic ions compared with BC/PMS system. Moreover, it was found that there were radical produced under the effect of Fe element, defects, functional groups, pyridinic N and pyrrolic N and non-radical caused by graphitic N, carbon atoms next to the iron atoms and better adsorption capacity in the FNBC/PMS system. It was observed that the contribution of hydroxyl radical (•OH), sulfate radical (SO4•-) and singlet oxygen (1O2), which were the main reactive oxygen species, during the CIP degradation, were 75.80%, 11.49% and 10.26%, respectively. Furthermore, total organic carbon (TOC) variation was analyzed and the degradation pathway of CIP was speculated. The application of this material could combine the recycling of sludge with the effective degradation of refractory organic pollutant, providing an environmentally friendly and economic method.


Assuntos
Ciprofloxacina , Esgotos , Peróxidos , Carbono , Catálise , Ferro
3.
J Colloid Interface Sci ; 625: 596-605, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35764041

RESUMO

In this study, biochar derived from municipal sludge (SBC) was modified by CoFe-Layered double hydroxides (CoFe-LDH), and used as adsorbent and oxidant for the removal of ciprofloxacin (CIP) for the first time. Under the optimal conditions, the CIP removal rate is increased by 24% compared with the single SBC, while the removal rates of total organic carbon and total nitrogen in the modified one are increased by 24% and 27%, respectively. Mechanism investigation suggested that the specific surface area and adsorption sites of modified biochar increased, and more CIP was adsorbed to the composite surface and then oxidized by more environmental persistent free radicals contained in the CoFe-LDH@SBC, when the adsorbed CIP molecules was oxidized and degraded, the adsorption sites can be freed and thus new CIP could be adsorbed to the CoFe-LDH@SBC. In addition, the plausible degradation pathways of CIP were proposed according to high-performance liquid chromatography-mass spectrometry and density functional theory calculation. It not only reveals that CoFe-LDH@SBC has the high ability of adsorption and oxidation for CIP removal but also sheds novel insight into the application of biochar.


Assuntos
Carvão Vegetal , Ciprofloxacina , Esgotos , Poluentes Químicos da Água , Absorção Fisico-Química , Adsorção , Carvão Vegetal/química , Ciprofloxacina/química , Hidróxidos , Esgotos/química , Poluentes Químicos da Água/química
4.
Water Sci Technol ; 69(2): 422-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24473315

RESUMO

To assess the performance of urban drainage systems in metropolitan areas in southern China, 12 urban drainage systems, including nine separate sewer systems (SSSs) and three combined sewer systems (CSSs) were monitored from 2008 to 2012 in Shanghai and Hefei. Illicit connection rates of SSS were determined. The results indicate that serious illicit connections exist for most SSSs. Annual volume balance for two SSSs with serious illicit connection was assessed with a hydraulic model to determine the dry weather overflow volume. Although interception facilities have been implemented in SSSs, for some systems with serious illicit connections, a considerable volume of dry weather overflow still existed. Combined with monitoring of dry/wet weather flow quality, the pollutant load caused by wet/dry weather overflow was quantified. The results revealed that there was no obvious advantage of having SSSs over CSSs in terms of pollutant control. The serious pollution caused by illicit connections and insufficient management occurs in many cities in China. The performance assessment of separate and CSSs in Shanghai and Hefei provides important lessons and practical experience that can be applied to the construction and management of urban drainage system in China as well as other developing countries.


Assuntos
Monitoramento Ambiental/métodos , Esgotos , China , Cidades
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 26(4): 469-73, 2009 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20017319

RESUMO

OBJECTIVE: To investigate the genetic polymorphism of 15 autosomal short tandem repeat (STR) loci, i.e. D5S818, FGA, D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX and D18S51, in Tibetan population of Changdu area, and to analyze the genetic relationship between this population and other Asian populations. METHODS: The 15 loci were amplified simultaneously using a multiplex PCR typing system. Amplified STR fragments were analyzed with an ABI PRISM 3100 Avant DNA Analyzer. Arlequin software version 3.1 was used to obtain allele frequencies and polymorphism parameters. RESULTS: There were 135 STR alleles in the 15 STRs of Changdu Tibetan, with allele frequencies ranging from 0.0065 to 0.5455. The average heterozygosity was 0.7340, the discrimination power was higher than 0.8 except for TPOX and TH01. The accumulative discrimination power was more than 0.9999998, and the accumulative non-parental exclusion probability was 0.99999997. CONCLUSION: The 15 STR loci of Changdu Tibetan possess characteristics of high genetic diversity. They can be employed in minority genetics investigation, and individual and paternity test in forensic medicine.


Assuntos
Povo Asiático/etnologia , Povo Asiático/genética , Repetições de Microssatélites , Polimorfismo Genético , Feminino , Humanos , Masculino , Linhagem , Tibet/etnologia
6.
Huan Jing Ke Xue ; 30(12): 3527-33, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20187382

RESUMO

Dry-weather flow quantity and quality of three representative separate storm sewer systems in Shanghai-H, G, N were studied. Based on survey of operating status of the pumping stations as well as characteristics of the drainage systems, it was obtained that the interception sewage volumes per unit area in the three systems were 3610 m3/(km2 x d), 1550 m3/(km2 x d), 2970 m3/(km2 x d) respectively; the sanitary wastewater included accounted for 25%, 85% and 71% respectively; the interception volume of H was mainly composed of infiltrated underground water, so the dry-weather flow pollution was slighter, and the interception volumes of G, N were both mainly composed of sanitary wastewater, so the dry-weather which were flow pollution was relatively serious. The water characteristics of potential illicit discharge sources of dry-weather which were flow-grey water, black water and underground water were preliminarily explored, so that treating three parameters-LAS/ NH4+ -N, NH4+ -N/K, Mg/K as tracer parameters of grey water, black water and underground water was put forward. Moreover, the water characteristics of grey water and sanitary wastewater including black water were summarized: the feature of grey water was LAS/NH4+ -N > 0.2, NH4+ -N/K <1, and sanitary wastewater was LAS/NH4+ -N < 0.2, NH4+ -N/K >1. Based on the above, the applications of flow chart method and CMBM method in dry-weather flow detection of monitored storm systems were preliminarily discussed, and the results were basically same as that obtained in flow quantity and quality comprehensive analysis. The research results and methods can provide guidance for analysis and diagnosis of dry-weather flow sources and subsequent reconstruction projects in similar separate storm sewer systems at home.


Assuntos
Drenagem Sanitária , Chuva , Esgotos , Movimentos da Água , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-349051

RESUMO

<p><b>OBJECTIVE</b>To investigate the genetic polymorphism of 15 autosomal short tandem repeat (STR) loci, i.e. D5S818, FGA, D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX and D18S51, in Tibetan population of Changdu area, and to analyze the genetic relationship between this population and other Asian populations.</p><p><b>METHODS</b>The 15 loci were amplified simultaneously using a multiplex PCR typing system. Amplified STR fragments were analyzed with an ABI PRISM 3100 Avant DNA Analyzer. Arlequin software version 3.1 was used to obtain allele frequencies and polymorphism parameters.</p><p><b>RESULTS</b>There were 135 STR alleles in the 15 STRs of Changdu Tibetan, with allele frequencies ranging from 0.0065 to 0.5455. The average heterozygosity was 0.7340, the discrimination power was higher than 0.8 except for TPOX and TH01. The accumulative discrimination power was more than 0.9999998, and the accumulative non-parental exclusion probability was 0.99999997.</p><p><b>CONCLUSION</b>The 15 STR loci of Changdu Tibetan possess characteristics of high genetic diversity. They can be employed in minority genetics investigation, and individual and paternity test in forensic medicine.</p>


Assuntos
Feminino , Humanos , Masculino , Povo Asiático , Etnologia , Genética , Repetições de Microssatélites , Linhagem , Polimorfismo Genético , Tibet , Etnologia
8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 30(2): 135-9, 2005 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-15898419

RESUMO

OBJECTIVE: To investigate the frequencies of allele and genotype of HLA-DRB1 gene in Luoba ethnic group. METHODS: HLA-DRB1 genes from 92 individuals of Luoba ethnic group in Tibet Autonomous region were investigated, using PCR-SSO (polymerase chain reaction -sequence specific oligo-nucleotide) genotyping methods. We compared allele frequencies of Luoba population in HLA-DRB1 locus with that of various ethnic groups distributed worldwide, constructed the phylogenetic tree by UPGMA (unweighted pair group method with arithmetic mean), and counted genetic distance by Nei measure. RESULTS: Of the 11 DRB1 alleles detected, the two most common genes were DRBI * 04( gene frequency: 27.20% ) and DRB * 12 (25.50%) , which covered 52.70% of the total alleles detected from Luoba ethnic group. The frequencies of HLA-DRB1 * 14(15.20% ), DRB1 * 15(9.80% ) and DRB1 * 08(8.20% ) were more than 5%. Luoba was unique in the distribution of HLA alleles. The genetic distance between Luoba and Tibetan was closer than that with other population. A dendrogram based on the DRB1 genes by cluster analysis suggested that Luoba ethnic group might cluster with Tibetan firstly, then cluster with other population living in China (except Uygr) , and cluster with Caucasian and Black finally. CONCLUSION: The HLA-DRBI gene frequency of Luoba individuals in Tibet Linzhi had some differences compared with that of other Chinese population. The kindred relation between Luoba and Tibetan was closer than that with other population, which was coincident with the results of ethnology, history and sociology.


Assuntos
Antígenos HLA-DR/genética , Polimorfismo Genético , China/etnologia , Feminino , Frequência do Gene , Genótipo , Cadeias HLA-DRB1 , Humanos , Masculino , Filogenia , Tibet/etnologia
9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-813419

RESUMO

OBJECTIVE@#To investigate the frequencies of allele and genotype of HLA-DRB1 gene in Luoba ethnic group.@*METHODS@#HLA-DRB1 genes from 92 individuals of Luoba ethnic group in Tibet Autonomous region were investigated, using PCR-SSO (polymerase chain reaction -sequence specific oligo-nucleotide) genotyping methods. We compared allele frequencies of Luoba population in HLA-DRB1 locus with that of various ethnic groups distributed worldwide, constructed the phylogenetic tree by UPGMA (unweighted pair group method with arithmetic mean), and counted genetic distance by Nei measure.@*RESULTS@#Of the 11 DRB1 alleles detected, the two most common genes were DRBI * 04( gene frequency: 27.20% ) and DRB * 12 (25.50%) , which covered 52.70% of the total alleles detected from Luoba ethnic group. The frequencies of HLA-DRB1 * 14(15.20% ), DRB1 * 15(9.80% ) and DRB1 * 08(8.20% ) were more than 5%. Luoba was unique in the distribution of HLA alleles. The genetic distance between Luoba and Tibetan was closer than that with other population. A dendrogram based on the DRB1 genes by cluster analysis suggested that Luoba ethnic group might cluster with Tibetan firstly, then cluster with other population living in China (except Uygr) , and cluster with Caucasian and Black finally.@*CONCLUSION@#The HLA-DRBI gene frequency of Luoba individuals in Tibet Linzhi had some differences compared with that of other Chinese population. The kindred relation between Luoba and Tibetan was closer than that with other population, which was coincident with the results of ethnology, history and sociology.


Assuntos
Feminino , Humanos , Masculino , China , Etnologia , Frequência do Gene , Genótipo , Antígenos HLA-DR , Genética , Cadeias HLA-DRB1 , Filogenia , Polimorfismo Genético , Tibet , Etnologia
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