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1.
Int. braz. j. urol ; 45(3): 549-559, May-June 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-1012314

RESUMO

ABSTRACT Objective: To study the expression patterns of long noncoding RNA (lncRNA) colon cancer-associated transcript 1 (CCAT1) and the changes in cell proliferation, apoptosis, migration and invasion induced by silencing CCAT1 in bladder cancer cells. Materials and Methods: The expression levels of CCAT1 were determined using realtime quantitative polymerase chain reaction in cancerous tissues and paired normal tissues from 34 patients with bladder cancer. The relationship between clinical characteristics and CCAT1 expression was analyzed. And then we conducted cell experiments. Bladder urothelial carcinoma cell lines T24 and 5637 cells were transfected with CCAT1 small interfering RNA (siRNA) or scramble siRNA. Cell proliferation and apoptosis changes were determined using a Cell Counting Kit-8 (CCK-8) assay and a flow cytometry assay. Migration and invasion changes were measured using a wound healing assay and a trans-well assay. microRNAs (miRNAs) were predicted by Starbase 2.0, and their differential expression levels were studied. Results: CCAT1 was significantly upregulated in bladder cancer (P < 0.05). CCAT1 upregulation was positively related to tumor stage (P = 0.004), tumor grade (P = 0.001) and tumor size (P = 0.042). Cell proliferation, migration and invasion were promoted by abnormally expressed CCAT1. miRNAs miR-181b-5p, miR-152-3p, miR-24-3p, miR-148a-3p and miR-490-3p were potentially related to the aforementioned functions of CCAT1. Conclusion: CCAT1 plays an oncogenic role in urothelial carcinoma of the bladder. In addition, CCAT1 may be a potential therapeutic target in this cancer.

2.
J Hazard Mater ; 379: 120756, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31254784

RESUMO

Although bisulfite is able to activate manganese oxides for enhanced oxidation of organic contaminants with donor-electron functions, the removal mechanisms for some esters remain poorly understood. In this study, we investigated the bisulfite/MnO2-accelerated transformation of methyl parathion (MP), a recalcitrant and toxic organophosphorus pesticide (OPP). The removal rate constants of MP depended on pH, oxygen conditions, and the ratio between [HSO3-] and [MnO2]. MP transformation declined by 36% with the addition of pyrophosphate as a scavenging agent for Mn(III)aq. [Mn(OH)(SO3H)]+, a reactive intermediate, may be involved in enhancing the transformation of MP. The overall reaction can be divided into three distinct processes. The first process comprises two steps: the dissolution of MnO2 reduced by HSO3- and the formation of a Mn-sulfite complex by a relatively fast substitution-controlled process. The second process is much slower and forms a precursor organometallic complex between the MP and Mn(IV/III). The third process involves a series of redox/hydrolysis reactions via aqueous and surface reactions. The mechanisms of each process were interpreted using kinetic observation and product identification data. This study improved the fundamental understanding of the MnO2/HSO3- reaction process, thereby increasing the feasibility for remediating OPP pollution of the soil-water environment.

3.
Int Braz J Urol ; 45(3): 549-559, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038865

RESUMO

OBJECTIVE: To study the expression patterns of long noncoding RNA (lncRNA) colon cancer-associated transcript 1 (CCAT1) and the changes in cell proliferation, apoptosis, migration and invasion induced by silencing CCAT1 in bladder cancer cells. MATERIALS AND METHODS: The expression levels of CCAT1 were determined using realtime quantitative polymerase chain reaction in cancerous tissues and paired normal tissues from 34 patients with bladder cancer. The relationship between clinical characteristics and CCAT1 expression was analyzed. And then we conducted cell experiments. Bladder urothelial carcinoma cell lines T24 and 5637 cells were transfected with CCAT1 small interfering RNA (siRNA) or scramble siRNA. Cell proliferation and apoptosis changes were determined using a Cell Counting Kit-8 (CCK-8) assay and a fl ow cytometry assay. Migration and invasion changes were measured using a wound healing assay and a trans-well assay. microRNAs (miRNAs) were predicted by Starbase 2.0, and their differential expression levels were studied. RESULTS: CCAT1 was signifi cantly upregulated in bladder cancer (P < 0.05). CCAT1 upregulation was positively related to tumor stage (P = 0.004), tumor grade (P = 0.001) and tumor size (P = 0.042). Cell proliferation, migration and invasion were promoted by abnormally expressed CCAT1. miRNAs miR-181b-5p, miR-152-3p, miR-24-3p, miR-148a-3p and miR-490-3p were potentially related to the aforementioned functions of CCAT1. CONCLUSION: CCAT1 plays an oncogenic role in urothelial carcinoma of the bladder. In addition, CCAT1 may be a potential therapeutic target in this cancer.


Assuntos
RNA Longo não Codificante/análise , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Idoso , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo , Feminino , Citometria de Fluxo , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real , Sincalida/análise , Fatores de Tempo , Regulação para Cima , Cicatrização/genética
4.
Chemosphere ; 226: 858-864, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30978597

RESUMO

Organophosphorus pesticides (OPPs), a kind of effective insecticide, have attracted extensive attention of researchers because of the high toxicity and refractory character of their degradation products. Given the ubiquity of manganese dioxide (MnO2) and bisulfite (HSO3-) in environmental media, the abiotic degradation of several typical OPPs by the MnO2-HSO3- reaction system was investigated in batch experiments. As a representative OPP, methyl parathion (MP) was chosen to be the focus of the study. The removal rate of MP was remarkably improved by adding bisulfite (HSO3-) to the MnO2 single-reaction system, and the oxidation product methyl paraoxon was below the detection limit. The primary active substances generated from the reaction system were determined to be Mn(III) species by adding excess radical scavengers or complexants (methanol and pyrophosphate) to the reaction system. On the basis of the metabolic products of MP identified by liquid chromatography-high-resolution mass spectrometry (LC/HRMS) and gas chromatography-mass spectrometry (GC/MS), the transformation pathway of MP in the MnO2-HSO3- reaction system was elicited, which included the predominant processes of hydrolysis and oxidation. Furthermore, the typical OPPs with different structures were also degraded efficiently by the reaction system because of the oxidative degradation of Mn(III). This study offers significative information related to the abiotic oxidation of manganese minerals and the fate and dissipation of OPPs in the actual environment.


Assuntos
Poluentes Ambientais/química , Compostos de Manganês/química , Óxidos/química , Praguicidas/química , Sulfitos/química , Cromatografia Gasosa-Espectrometria de Massas , Hidrólise , Cinética , Metil Paration/análise , Metil Paration/química , Organofosfatos/química , Oxirredução , Praguicidas/análise
5.
Sci Total Environ ; 652: 52-58, 2018 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-30359801

RESUMO

Methylmercury (MeHg) is a toxic compound. It forms mainly in reducing environments, and then degrades through biogeochemical processes. Photodegradation and microorganism degradation of MeHg are among the processes that have been reported. However, little attention has been focused on the abiotic degradation of MeHg in soil/sediment without light. In our study, the percent MeHg of total Hg in Guangzhou soil in southern China was found to be variable and exhibited a significant negative correlation with the content of Fe or Cu where annite (KFe2+3(AlSi3O10)(OH)2), a Fe-bearing mineral, was identified. To understand the mechanisms of radical-initiated MeHg degradation by Fe/Cu-containing components, batch experiments were done. Results showed that annite in the soils could activate O2 to generate OH and O2- and facilitate MeHg degradation under oxic conditions. Meanwhile, Cu components in the soil further enhanced the production of O2-, and was oxidized to Cu(III) promoting degradation of MeHg directly. These findings help us understand that the distribution of MeHg in soil depends on not only external pollution sources, but also on biogeochemical processes in subsurface environments.

6.
Can Urol Assoc J ; 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30169147

RESUMO

INTRODUCTION: This single-centre, retrospective study aimed to assess the efficacy and safety of flexible ureteroscopy (FURS) combined with holmium laser lithotripsy in treating children with upper urinary tract stones. METHODS: From June 2014 to October 2015, a total of 100 children (74 boys and 26 girls) with upper urinary tract stones were treated using FURS. A 4.7 Fr Double-J stent was placed two weeks before operation. Patients were considered stone-free when the absence of residual fragments was observed on imaging studies. The preoperative, operative, and postoperative data of the patients were retrospectively analyzed. RESULTS: A total of 100 pediatric patients with a mean age of 3.51±1.82 years underwent 131 FURS and holmium laser lithotripsy. Mean stone diameter was1.49±0.92 cm. Average operation time was 30.8 minutes (range 15-60). The laser power was controlled between 18 and 32 W, and the energy maintained between 0.6 and 0.8 J at any time; laser frequency was controlled between 30 and 40 Hz. Complications were observed in 69 (69.0 %) patients and classified according to the Clavien system. Postoperative hematuria (Clavien I) occurred in 64 (64.0 %) patients. Postoperative urinary tract infection with fever (Clavien II) was observed in eight (7%) patients. No ureteral perforation and mucosa avulsion occurred. The overall stone-free rate of single operation was 89/100(89%). Stone diameter and staghorn calculi were significantly associated with stone-free rate. CONCLUSIONS: FURS and holmium laser lithotripsy is effective and safe in treating children with upper urinary tract stones.

7.
8.
Chemosphere ; 176: 288-295, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28273536

RESUMO

Although the kinetics and transformation of methyl parathion have been investigated extensively, its abiotic degradation mechanism in anoxic sulfur-containing groundwater system is still not clear. In this work, the abiotic degradation of methyl parathion in anoxic sulfur-containing system mediated by natural organic matter (NOM) was investigated in batch experiments. It was found that the removal of methyl parathion (up to 80.7%) was greatly improved in sulfide containing NOM compared to those in sulfide alone (with 15.5%) and in NOM alone (almost negligible). Various sulfur species presented significant differences in behaviors methyl parathion degradation, but followed by the pseudo-first-order model well. No facilitated degradation of methyl parathion was observed in sulfite (SO32-) or thiosulfate (S2O32-) containing NOM such as anthraquinone. Although elemental sulfur (S0) and cysteine could further improve the degradation rate of methyl parahtion, their impacts was very limited. The removal efficiency of methyl parathion in anoxic sulfur-containing system were related remarkably with NOM concentration and solution pH. Based on the transformation products identified by gas chromatography-mass spectrometer (GC/MS) and liquid chromatography high resolution mass spectrometer (LC/HRMS), both the nitro group reduction and hydrolysis (SN@C) processes by sulfide (HS-) were further proved to be two predominant reaction mechanisms for the abiotic degradation of methyl parathion in anoxic sulfur-containing system. The results of this study help to understand the natural attenuation of methyl parathion under anoxic sulfide-containing groundwater system mediated by NOM.


Assuntos
Substâncias Húmicas/análise , Metil Paration/análise , Compostos de Enxofre/química , Poluentes Químicos da Água/análise , Cromatografia Gasosa-Espectrometria de Massas , Hidrólise , Cinética , Modelos Teóricos , Soluções , Sulfetos/química , Sulfitos/química , Tiossulfatos/química
9.
Huan Jing Ke Xue ; 38(4): 1597-1605, 2017 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965164

RESUMO

In order to study the distribution characteristics of organophosphorus pesticides (OPPs)in the soil of Jianghan plain,78 profile-soil samples from various depth and 7 surface-soil samples were collected in September,2015 in established groundwater monitoring field site, Jianghan plain. The OPPs concentrations were determined by gas chromatography with nitrogen-phosphorus detector(GC-NPD). The results showed that OPPs were widespread in our studied area. The OPPs concentrations of suface-soil samples ranged from 89.80 ng·g-1 to 193.85 ng·g-1,with an average of 140.05 ng·g-1, whereas the OPPs concentrations of profile-soil samples ranged from 19.81 ng·g-1 to 138.28 ng·g-1,with an average of 40.99 ng·g-1. The main ingredients of OPPs in surface and profile soil samples were methamidophos, omethoate, diazinon and quinalphos,and the residual amount of 10 kinds of OPPs had posed a threat to agricultural products according to the America soil pesticide residue limits standards. The horizontal distribution of OPPs concentration in profile soil followed the order of nearby river farm area > nearby river area > farm area, namely GS1-1 > GS4 > GS2 > GS3. while the vertical distribution mostly decreased at first and then increased with increasing depth. The distribution characteristics of OPPs were also influenced by many factors, such as application amount of OPPs, the adsorption and desorption actions of soil, vertical movement of groundwater, the terrain environment in the study area, and the concentration of soil organic matters.

10.
Chemosphere ; 150: 90-96, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26891361

RESUMO

Methyl parathion, a widely used insecticide around the world, has aroused gradually extensive concern of researchers due to its degradation product such as methyl paraoxon, with higher toxicity for mammals and more recalcitrant. Given the ubiquity of manganese dioxide (MnO2) in soils and aquatic sediments, the abiotic degradation of methyl parathion by α-MnO2 was investigated in batch experiments. It was found that methyl parathion was decomposed up to 90% by α-MnO2 in 30 h and the removal efficiency of methyl parathion depended strongly on the loading of α-MnO2 and pH value in the solution where the reactions followed pseudo-first-order model well. The coexisting metal ions (such as Ca(2+), Mg(2+) and Mn(2+)) weakened markedly the degradation of methyl parathion by α-MnO2. However, the effect of dissolved organic matter (HA-Na) on reaction rates presented two sides: to improve hydrolysis rate but deteriorate oxidation rate of methyl parathion. Based on the degradation products identified by gas chromatography-mass spectrometer (GC/MS) and liquid chromatography high-resolution mass spectrometer (LC/HRMS), both hydrolysis and oxidation processes were proposed to be two predominant reaction mechanisms contributing to methyl parathion degradation by α-MnO2. This study provided meaningful information to elucidate the abiotic dissipation of methyl parathion by manganese oxide minerals in the environment.


Assuntos
Poluentes Ambientais/análise , Inseticidas/análise , Compostos de Manganês/química , Metil Paration/análise , Modelos Químicos , Óxidos/química , Animais , Poluentes Ambientais/química , Recuperação e Remediação Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Hidrólise , Inseticidas/química , Cinética , Metil Paration/química , Oxirredução
11.
Environ Sci Pollut Res Int ; 22(24): 19747-55, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26278904

RESUMO

Organophosphorus pesticides (OPPs), a kind of widely used pesticides, are currently attracting great attention due to their adverse effects on human central nervous systems, particularly in children. Although the hydrolysis behavior of OPPs has been studied well, its hydrolysis mechanism remained controversial, especially at various pH conditions, partly due to their relatively complex structures and abundant moieties that were prone to be attacked by nucleophiles. The Q-Exactive mass spectrometer, part of those hybrid high-resolution mass spectrometers (HRMS), was used to determine hydrolysis products of methyl parathion (MP), a kind of OPPs in situ buffer aqueous solution with pH ranging from 1 to 13 in this study. Most of the complex hydrolysis products of MP were identified due to the high sensitivity and accuracy of HRMS. The results demonstrated that the hydrolysis rate and pathway of MP were strong pH dependent. With the increase of pH, the hydrolysis rate of MP increased, and two different reaction mechanisms were identified: SN (2)@P pathway dominated the hydrolysis process at high pH (e.g., pH ≥ 11) while SN (2)@C was the main behavior at low pH (e.g., pH ≤ 9). This study helps understand the hydrolysis mechanism of OPPs at various pH and extends the use of Q-Exactive mass spectrometry in identifying organic pollutants and their degradation products in environmental matrices.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Espectrometria de Massas/métodos , Metil Paration/análise , Praguicidas/análise , Monitoramento Ambiental/instrumentação , Concentração de Íons de Hidrogênio , Hidrólise
12.
Huan Jing Ke Xue ; 36(1): 172-8, 2015 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-25898661

RESUMO

Sewage irrigation has been widely used in areas of water shortage in northern China, and it may introduce organic contaminants into groundwater. To characterize the organic contaminants in groundwater in sewage irrigation area, the Xiaodian sewage irrigation area in Shanxi Province was chosen as the case study area. A total of 16 groundwater samples (13 from shallow aquifer, 3 from deep aquifer) were collected. Polycyclic aromatic hydrocarbons (PAHs) were determined by gas chromatography-mass spectrometry (GC-MS) and organochlorine pesticides (OCPs) were ainalyzed by gas chromatography-electron capture detection (GC-ECD). The results showed that the concentrations of PAHs ranged from 13.98 to 505.89 ng x L(-1) with an average concentration of 115.67 ng x (L)(-1). The 2 and 3 ring-PAHs were the main components, while naphthalene and phenanthrene were most frequently detected. The concentrations of OCPs were in the range of 13.91-103.23 ng x L(-1) with an average concentration of 40.99 ng x L(-1), while alpha-HCH, delta-HCH, o,p'-DDD, Aldrin, Endosulfan-sulfate and HCB were most frequently detected. Overall, shallow aquifers appeared more contaminated with these pollutants than deep aquifers. In the area, the order of the organic contaminants concentration in groundwater was: East Main Channel < Beizhang Drainage < Taiyu Drainage, which indicated the quality of groundwater was influenced by the sewage irrigation.


Assuntos
Monitoramento Ambiental , Água Subterrânea/química , Resíduos de Praguicidas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Irrigação Agrícola , China , Cromatografia Gasosa , Cidades , Endossulfano/análogos & derivados , Cromatografia Gasosa-Espectrometria de Massas , Hexaclorocicloexano , Hidrocarbonetos Clorados/análise , Esgotos
13.
Ecotoxicology ; 23(10): 1943-50, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25139034

RESUMO

31 topsoil samples were collected by grid method in Xiaodian sewage irrigation area, Taiyuan City, North of China. The concentrations of 16 kinds of polycyclic aromatic hydrocarbons (PAHs) were determined by gas chromatograph coupled with mass spectrum. Generally speaking, the distribution order of PAHs in the area is: those with five and six rings > those with four rings > those with two and three rings. Source apportionment shows a significant zonation of the source of PAHs: the civil coal pollution occurred in the north part, the local and far factory pollution happened in the middle area and the mixed pollution sources from coal and wood combustion, automotive emission, presented in the south area. The distribution of PAHs has a definite relationship with the sewage water flow and soil adsorption. The related coefficient between PAHs and physicochemical property showed there was a negative correlation between pH, silt, clay and PAHs while there was a positive correlation between total organic carbon, sand and PAHs.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Solo/química , Agricultura/métodos , China , Eliminação de Resíduos Líquidos/métodos
14.
Talanta ; 122: 234-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24720989

RESUMO

A low power dielectric barrier discharge excitation source was developed to determine arsenic in a cost-effective manner. Arsenic in water was reduced to AsH3 by hydride generation (HG), which was transported to the miniature dielectric barrier discharge (DBD) excitation source for excitation and optical detection at As 193.7 nm atomic line. The DBD source consists of a quartz tube, a tungsten rod electrode, and a copper coil electrode. The main operation parameters and the potential interferences affecting the determination were investigated. The detection limit for arsenic with the proposed DBD-AES was 4.8 µg L(-1) when the HG products were dried with concentrated H2SO4 before introducing to DBD. Repeatability, expressed as the relative standard deviation of the spectral peak height, was 2.8% (n=11) for 0.1 mg L(-1) arsenic solution. The proposed method was successfully applied to the determinations of certified reference material (GBW08605) and nature water samples.


Assuntos
Arsênico/análise , Espectroscopia Dielétrica/normas , Espectrofotometria Atômica/normas , Espectroscopia Dielétrica/métodos , Espectrofotometria Atômica/métodos
15.
Sci Total Environ ; 473-474: 530-6, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24388903

RESUMO

The reuse of wastewater for irrigation of agricultural land is a well established resources management practice but has the disadvantage of inputting various forms of contaminants into the terrestrial environment including nonylphenol (NP), a well known endocrine disrupting substance. To elucidate the environmental fate and transport of NP, the sorption behavior on sewage-irrigated soil was studied by batch experiment. It was found that sorption processes of NP on different sorbents (soil, humic acid (HA) and silica) could be expressed well using two compartment pseudo first-order model, where both surface and intra-particle diffusion were probable rate-controlling processes. Linear model could better express the sorption of NP on soil, black carbon (BC) and mineral (e.g., SiO2) except HA than Freundlich model. The large value of distribution coefficients of normalized organic carbon (Koc) on soils indicated that NP was limited to migrate to deep soil. The higher desorption partition coefficient of NP on soil showed enhanced hysteresis. According to the experimental data, the calculated thermodynamic parameters implied that the sorption reaction on sewage-irrigation was spontaneous, exothermic and entropy decreasing process. The amount of soil organic matter (SOM) dominated the sorption capacity, whereas the sorption behavior of NP on soil showed no significant correlation with ionic strength.


Assuntos
Irrigação Agrícola/métodos , Fenóis/química , Poluentes do Solo/química , Solo/química , Eliminação de Resíduos Líquidos/métodos , Adsorção , Substâncias Húmicas , Cinética , Modelos Químicos , Fenóis/análise , Dióxido de Silício/química , Poluentes do Solo/análise , Termodinâmica
16.
Huan Jing Ke Xue ; 34(8): 3211-5, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24191570

RESUMO

Nine profile soil samples and two sewage water samples were collected from Xiaodian sewage irrigation area in Taiyuan city, concentrations of organochlorine pesticides (OCPs) were determined by the gas chromatography coupled with electron capture detector (GC-ECD) to analyze the influence of the leakage of sewage water. The result shows that OCPs in sewage water were mainly composed of HCHs. Concentrations of DDTs and other organochlorine pesticides were very low or out of the detection limit. Concentrations of sigmaOCPs and HCHs in eight profiles near irrigation channels to some extend decreased with the increasing of the linear distance off the channel, which shows influences of the leakage of sewage water on the soil nearby. Concentrations of HCHs clearly decreased with the increasing of soil depth in most profile soils. For the horizontal direction, concentrations of HCHs also decreased with the increasing of the linear distance off the channel. The correlation between HCHs and TOC was positive, but no correlation between pH and HCHs was found.


Assuntos
Hidrocarbonetos Clorados/química , Praguicidas/química , Poluentes do Solo/química , Solo/química , Águas Residuárias/química , China , Cromatografia Gasosa , Cidades , Monitoramento Ambiental , Esgotos/química
17.
Huan Jing Ke Xue ; 34(4): 1553-60, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23798142

RESUMO

Nine profile soil samples were collected from Xiaodian sewage irrigation area, Taiyuan city, China. The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were analyzed by gas chromatography equipped with a mass spectrometry detector (GC/ MS). The rank order of the average concentrations of PAHs in the 0-10 cm upper soil layer was background area < swamp area < groundwater irrigation area < sewage irrigation area. The concentrations of PAHs in most profile soils decreased with the increase of depth, and the PAHs were mainly accumulated in the surface soil layer (0-40 cm). 4-6 rings of PAHs were mainly accumulated in the 0-50 cm soil layer, and the accumulation capacity in groundwater-irrigation area was better than that in sewage irrigation area. The correlation between different rings of PAHs and TOC was positive (r(max) = 0.791, P = 0), and the same situation was found for PAHs and sand (r(max) = 0. 882, P = 0). The correlation between PAHs and pH was negative (r(min) = -0.1, P = 0.702). The main source of PAHs in the surface soil layer (0-40 cm) of study area was coal combustion. There were two pollution ways of PAHs in soil, one was settled into soil directly, the other was first settled into water and absorbed on the surface of solid particles, and then got enrichment in soil as irrigation water flew.


Assuntos
Irrigação Agrícola , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Esgotos , Poluentes do Solo/análise , Irrigação Agrícola/métodos , China , Águas Residuárias/química , Movimentos da Água
18.
Chemosphere ; 92(4): 337-43, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23402916

RESUMO

Serious shortage of water resources is one of the major factors restricting the sustainable development of cropland and pasture land in northern and northwestern China. Although the reuse of wastewater for agricultural irrigation becomes a well established practice in these regions, many contaminants have been also introduced into the soil-groundwater systems such as persistent organochlorine pesticides (OCPs). To study the influence of long-term sewage irrigation on the distribution of OCPs in soil-groundwater systems, the groundwater flow field was investigated and 31 topsoil samples, 9 boreholes, 11 sewage effluents and 34 groundwater samples were collected in Xiaodian, Taiyuan city, one of the largest sewage irrigation districts, China. During sampling, three representative types of regions were considered including effluent-irrigated area, groundwater-irrigated area served as the control field and no-irrigated area as reference "background". The results showed over-exploitation of groundwater had changed the flow field of groundwater and wherever in soil or in groundwater, the concentration of OCPs in effluent-irrigation area presented the highest value, which indicated that the sewage irrigation had a strong influence on the distribution of OCPs in soil-groundwater systems. Principal component analysis for OCPs content in groundwater showed that the major influence factors on the occurrence and distribution of OCPs in groundwater systems attribute to the flow field of groundwater and to the current pesticide use.


Assuntos
Água Subterrânea/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Esgotos/análise , Solo/química , Irrigação Agrícola , Cromatografia Gasosa , Análise de Componente Principal
19.
Huan Jing Ke Xue ; 33(10): 3495-500, 2012 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-23233979

RESUMO

Gel permeation chromatography was applied to analyze the variation characteristics of molecular mass of DOM six fractions during photocatalytic degradation. The results showed that most of DOM with average relative molecular mass was below 10(4). Large molecular fractions higher than 10(4) mainly containing HIB and HIN, accounted for nearly 20% of total DOM. Relative molecular mass of other fractions was mainly from 10(3) to 10(4). Fractions with relative molecular mass less than 500 were little. Most of DOM in leachate was yellow humic acid with moderate relative molecular mass and that is difficult to be biologically degraded. Relative molecular mass distribution of DOM fraction in different effluent broadened gradually during photocatalytic process, while polydispersity distribution coefficient (D) increased gradually. Relative molecular mass of HOB, HIB, HIA and HON decreased notably after photocatalytic treatment, especially HOB which relative molecular mass decreased from initial (4-25) x 10(3) to (0.4-1) x 10(3) after 72 h degradation. On the contrary, relative molecular mass of HOA and HIN tended to increase, and the more obvious is HOA which relative molecular mass increased from (2-20) x 10(3) of raw leachate to (20-50) x 10(3) of 72 h effluent. RID peak signal intensity of each DOM fraction decreased with the treatment time, which illustrated that the concentration decreased. As a whole, all fractions of DOM can be photocatalytically transformed efficiently.


Assuntos
Compostos Orgânicos/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Biodegradação Ambiental , Catálise , Compostos Orgânicos/química , Fotoquímica , Solubilidade , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/química
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(6): 1575-9, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22870642

RESUMO

Three-dimensional excitation emission matrix fluorescence spectroscopy (3D-EEM) was applied to analyze the fluorescence characterization of dissolved organic matter in landfill leachate. The results showed that fulvic-like, tryptophan-like and humic acids-like matters were the main compounds in landfill leachate. A number of UV fulvic-like matters led to ineffective biodegradation of leachate. HOA contained more UV fulvic-like and less Vis fulvic-like, by contrary to HIA; HIN was mainly composed of UV fulvic-like and Vis fulvic-like matters; HOB, HIB and HIN had more intense fluorescence signal, whose fluorescence peaks occurred in the region of fulvic-like, tryptophan-like and humic acids-like. This was similar to the original leachate as well as HON which had relatively weak fluorescence signal. Moreover, different fractions had different fluorescence signal intensity in different regions. HOB and HIB had more intense signal in the region of UV fulvic-like. HIN had more intense signal in the region of UV fulvic-like and Vis fulvic-like. HON had moderately intense signal in the whole region. HOA and HIA had relatively weak fluorescence signal.

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