Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 62
Filtrar
1.
Mol Pharm ; 21(4): 1942-1951, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38447198

RESUMO

The stimulator of interferon genes (STING) is pivotal in mediating STING-dependent type I interferon production, which is crucial for enhancing tumor rejection. Visualizing STING within the tumor microenvironment is valuable for STING-related treatments, yet the availability of suitable STING imaging probes is limited. In this study, we developed [18F]AlF-ABI, a novel 18F-labeled agent featuring an amidobenzimidazole core structure, for positron emission tomography (PET) imaging of STING in B16F10 and CT26 tumors. [18F]AlF-ABI was synthesized with a decay-corrected radiochemical yield of 38.0 ± 7.9% and radiochemical purity exceeding 97%. The probe exhibited a nanomolar STING binding affinity (KD = 35.6 nM). Upon administration, [18F]AlF-ABI rapidly accumulated at tumor sites, demonstrating significantly higher uptake in B16F10 tumors compared to CT26 tumors, consistent with STING immunofluorescence patterns. Specificity was further validated through in vitro cell experiments and in vivo blocking PET imaging. These findings suggest that [18F]AlF-ABI holds promise as an effective agent for visualizing STING in the tumor microenvironment.


Assuntos
Benzimidazóis , Radioisótopos de Flúor , Tomografia por Emissão de Pósitrons , Microambiente Tumoral , Linhagem Celular Tumoral , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/química , Benzimidazóis/química , Benzimidazóis/farmacologia , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Humanos
2.
Environ Res ; 222: 115322, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36693467

RESUMO

The presence of antibiotics in water bodies seriously threatens the ecosystem and human health. Advanced oxidation processes (AOPs) based on peroxymonosulfate (PMS), an effective method to remove antibiotics, have a bottleneck problem that the low oxidant utilization is attributed to the hindered electron transfer between metal oxides and peroxides. Here, CuO with rich oxygen vacancies (OVs), MSCuO-300, was synthesized to efficiently degrade tetracycline hydrochloride (TTCH) (k = 0.095 min-1). The dominant role of direct adsorption and activation of OVs and its regulated Cu-O, rather than surface hydroxyl adsorption, mediated a short-range catalytic pathway. The shortened catalytic pathway between active sites and PMS accelerated the charge transfer at the interface, which promoted PMS activation. Compared with CuxO-500 and Commercial CuO, the activation rate of PMS was increased by 11.97, and 12.64 times, respectively. OVs contributed to the production of 1O2 and O2•-, the main active species. In addition, MSCuO-300/PMS showed excellent adaptability to real water parameters, such as pH (3-11), anions, and continuous reactor maintained for 168 h. This study provides a successful case for the purification of antibiotic-containing wastewater in the design of efficient catalysts by oxygen defect strategies.


Assuntos
Oxigênio , Tetraciclina , Humanos , Ecossistema , Peróxidos/química , Antibacterianos , Água
3.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(4): 384-389, 2021 Jul 30.
Artigo em Chinês | MEDLINE | ID: mdl-34363362

RESUMO

In order to improve the level of epidemic prevention and control, and strengthen the observation and monitoring of potential patients with viral pneumonia in isolated state, a medical intelligent monitoring collar based on DA14699 Bluetooth low-power chip was proposed. DA14699 chip is used as the main controller in the design scheme, and the temperature, cough and location information of potential patients are recorded and analyzed by its high-efficiency wireless multi-core processing ability. The LIS3DH three-axis acceleration sensor is used to judge the cough symptoms. The MLX90640 infrared sensor is used to continuously measure the body temperature. The L218 four frequency GSM / GPRS positioning module is used to complete the rapid and accurate positioning of personnel, so as to realize the comprehensive supervision of the implementation of home isolation measures. DA14699 chip supports Bluetooth BLE5.1 protocol. Epidemic prevention personnel can transmit and read the data recorded in the smart collar from a long distance, and display it directly on the intelligent Bluetooth handheld terminal, effectively avoid the risk of infection caused by close contact. Through the actual test, the monitoring function of the key parameters of the collar is reliable and has high application value.


Assuntos
Pneumonia Viral , Humanos , Monitorização Fisiológica
4.
J Environ Sci (China) ; 84: 1-12, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31284901

RESUMO

A series of functional organic-metal AgCl-decorated graphitic carbon nitride (AgCl-CNx) composites were synthesized and applied for the degradation of oxalic acid (OA) under visible light. The highest photocatalytic activity was achieved with AgCl decoration ratio of 1.0 (denoted as AgCl-CN1.0). The pseudo-first-order constant for OA degradation was 0.0722 min-1 with the mineralization efficiency of 90.80% after 60 min reaction in the photocatalytic process with AgCl-CN1.0. A variety of characterization techniques including Brunauer-Emmett-Teller, X-ray diffraction, scanning electron microscope, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectra, ultraviolet-visible diffuse reflectance spectra, photoluminescence, and Mott-Schottky were utilized to elucidate the physicochemical, microstructure, and optical properties contributing to the improvement of the photocatalytic performance. The results showed that AgCl-CN1.0 had an oblate flaky erythrocyte-like structure with a moderate band gap energy of ~3.00 eV. In addition, the effects of the key parameters (i.e., AgCl-CN1.0 dosage, initial OA concentration, solution pH, and presence of natural organic matter) on OA degradation were systematically investigated. Radical scavenger experiments indicated that photogenerated holes, electrons, superoxide anion radicals, and hydroxyl radicals were the dominant reactive species. Moreover, AgCl-CN1.0 exhibited excellent stability and reusability for OA degradation without detectable Ag+ release in the solution over multiple reaction cycles. The efficient OA mineralization could be mainly ascribed to the moderate specific surface area, increased numbers of active sites, and effective interfacial charge transfer of AgCl-CN1.0. Overall, the AgCl-CN1.0 composite was demonstrated to be a highly efficient, stable, and recoverable photocatalyst.


Assuntos
Grafite/química , Compostos de Nitrogênio/química , Ácido Oxálico/química , Fotólise , Compostos de Prata/química , Poluentes Químicos da Água/química
5.
Cell Physiol Biochem ; 43(1): 172-181, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848139

RESUMO

BACKGROUND/AIMS: Adiponectin (Apn) is a multifunctional adipokine that circulates as several oligomeric complexes in the blood stream. Previous reports showed that several conserved lysine residues within the N-terminal collagenous domain of Apn are modified by hydroxylation and glycosylation. Here, we investigated the potential roles of post-translational modifications of Apn on the function of human vascular smooth muscle cells (VSMCs). METHODS: Blood samples of 92 coronary artery disease (CAD) patients and 20 healthy volunteers were collected and total and high molecular weight (HMW) Apn concentration and glycosylation were analyzed. RESULTS: The results revealed that total and HMW Apn derived from blood samples of CAD patients with severe stenosis significantly increased, however the glycosylation of HMW Apn significantly decreased. Functional studies of human VSMCs revealed that glycosylated Apn significantly inhibited the oxidized LDL-induced lipid accumulation, proliferation and migration of VSMCs, whereas non-glycosylated Apn had no inhibitory effects. CONCLUSION: Taken together, these data suggest that glycosylation of Apn is critically involved in regulating function against atherosclerosis by inhibiting lipid accumulation and proliferation and migration of VSMCs.


Assuntos
Adiponectina/metabolismo , Doença da Artéria Coronariana/patologia , Adiponectina/antagonistas & inibidores , Adiponectina/sangue , Adiponectina/genética , Estudos de Casos e Controles , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colesterol/análise , Doença da Artéria Coronariana/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Glicosilação , Humanos , Lipoproteínas LDL/farmacologia , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Índice de Gravidade de Doença
6.
J Environ Sci (China) ; 61: 3-13, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29191312

RESUMO

Enhanced ozonation degradation of atrazine (ATZ) with nano-ZnO (nZnO) as catalyst and the influences of the operational parameters have been investigated through semi-continuous experiments in this study. The results demonstrated that the combination of ozone (O3) and nZnO showed an obvious synergetic effect and the ATZ degradation conformed to pseudo-first-order kinetics. An improvement of ATZ degradation efficiency by 41.8% and pseudo-first-order rate constant by more than a factor of four was obtained in the O3/nZnO process after 5min of reaction compared to O3 alone. Meanwhile, the degradation efficiency of ATZ was gradually enhanced with increasing nZnO dosage and initial pH in the range from 3.0 to 8.0, and a higher amount of ATZ was degraded when the initial concentration of ATZ rose from 0.5 to 5mg/L. Additionally, sulfate ion, chloride ion, nitrate ion and low concentrations of humic acid substances led to enhancement of the ATZ degradation. The notable decrease of ATZ removal efficiency observed in the presence of radical scavengers and the results of free radical tests indicated that OH is the dominant active radical species. The mechanism investigation demonstrated that the enhancement effect could be attributed to the introduction of nZnO, which could promote the utilization of O3, enhance the formation of superoxide radical, and further accelerate the production of hydrogen peroxide and the generation of OH/O2-.


Assuntos
Atrazina/química , Ozônio/química , Poluentes Químicos da Água/química , Atrazina/análise , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Cinética , Modelos Químicos , Poluentes Químicos da Água/análise , Óxido de Zinco
7.
Biochemistry (Mosc) ; 79(7): 663-71, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25108329

RESUMO

The purpose of the present study was to examine changes in preadipocytes following the coculture of preadipocytes and adipocytes and the effects on the secretion of adipocytes and macrophages following induction of inflammation and insulin resistance. Mature adipocytes and RAW264.7 macrophages were treated with lipopolysaccharide and insulin to establish models of inflammation and insulin resistance, respectively. The mRNA expression levels of IL-6, MCP-1, and TNF-α in all adipocyte treatment groups were significantly greater compared with the control, and that of adiponectin was less (P<0.05). In the RAW264.7 macrophages, the mRNA expression levels of IL-6 and TNF-α were greater than those in the control group (P<0.05). Moreover, the results of this study confirmed that adipocytes and macrophages increased the secretion of inflammatory factors under conditions of induced inflammation and insulin resistance. In addition, 3T3-L1 adipocytes inhibited the proliferation and differentiation of preadipocytes when cocultured with adipocytes under conditions of inflammation and/or insulin resistance, and the phenotype of preadipocytes did not change.


Assuntos
Adipócitos/metabolismo , Resistência à Insulina , Macrófagos/metabolismo , Células 3T3-L1 , Adipocinas/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Forma Celular , Técnicas de Cocultura , Inflamação/metabolismo , Camundongos
8.
J Colloid Interface Sci ; 658: 714-727, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38141393

RESUMO

This work developed a novel chalcopyrite (CuFeS2) incorporated catalytic ceramic membrane (CFSCM), and comprehensively evaluated the oxidation-filtration efficiency and mechanism of CFSCM/peroxymonosulfate (PMS) for organics removal and membrane fouling mitigation. Results showed that PMS activation was more efficient in the confined membrane pore structure. The CFSCM50/PMS filtration achieved almost complete removal of 4-Hydroxybenzoic acid (4-HBA) under the following conditions: pH = 6.0, CPMS = 0.5 mM, and C4-HBA = 10 mg/L. Meanwhile, the membrane showed good stability after multiple uses. During the reaction, SO4•- and •OH were generated in the CFSCM50/PMS system, and SO4•- was considered to be the dominant reactive species for pollutant removal. The roles of copper, iron, and sulfur species, as well as the possible catalytic mechanism were also clarified. Besides, the CFSCM50/PMS catalytic filtration exhibited excellent antifouling properties against NOM with reduced reversible and irreversible fouling resistances. The Extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory analysis showed an increased in repulsive energy at the membrane-foulant interface in the CFSCM50/PMS system. Membrane fouling model analysis indicated that standard blocking was the dominant fouling pattern for CFSCM50/PMS filtration. Overall, this work demonstrates an efficient catalytic filtration process for foulants removal and outlines the synergy of catalytic oxidation and interface interaction.

9.
Chemosphere ; 362: 142632, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897319

RESUMO

Investigating the effects of g-C3N4-based photocatalysts on experimental parameters during tetracycline (TC) degradation can be helpful in discovering the optimal parameter combinations to improve the degradation efficiencies in general. Machine learning methods can avoid the problems of high cost, time-consuming and possible instrumental errors in experimental methods, which have been proven to be an effective alternative for evaluating the entire experimental process. Eight typical machine learning models were explored for their effectiveness in predicting the TC degradation efficiencies of g-C3N4 based photocatalysts. XGBoost (XGB) was the most reliable model with R2, RMSE and MAE values of 0.985, 4.167 and 2.900, respectively. In addition, XGB's feature importance and SHAP method were used to rank the importance of features to provide interpretability to the results. This study provided a new idea for developing g-C3N4-based photocatalysts for TC degradation and intelligent algorithms for predicting the photocatalytic activity of g-C3N4-based photocatalysts.

10.
Sci Total Environ ; 921: 171107, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38387560

RESUMO

Soil contamination by Cr(VI) has attracted widespread attention globally in recent years, but it remains a significant challenge in developing an environmentally friendly and eco-sustainable technique for the disposal of Cr(VI)-contaminated soil. Herein, a sustainable cyclic soil washing system for Cr(VI)-polluted soil remediation and the recovery of washing agents using biochar supported nanoscale zero-valent iron (nZVI-BC) was established. Citric acid (CA) was initially screened to desorb Cr(VI) from contaminated soil, mobilizing Cr from the highly bioaccessible fractions. The nZVI-BC exhibited superior properties for Cr(VI) and Cr(total) removal from spent effluent, allowing effective recovery of the washing agents. The elimination mechanism of Cr(total) by nZVI-BC involved the coordinated actions of electrostatic adsorption, reduction, and co-precipitation. The contributions to Cr(VI) reduction by Fe0, surface-bound Fe(II), and soluble Fe(II) were 0.6 %, 39.8 %, and 59.6 %, respectively. Meanwhile, CA favored the activity of surface-bound Fe(II) and Fe0 in nZVI-BC, enhancing the production of soluble Fe(II) to strengthen Cr(VI) removal. Finally, the recovered washing agent was proven to be reused three times. This study showcases that the combined soil washing using biodegradable chelant CA and effluent treatment by nZVI-BC could be a sustainable and promising strategy for Cr(VI)-contaminated soil remediation.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Poluentes Químicos da Água , Ferro , Solo , Poluentes do Solo/análise , Carvão Vegetal , Cromo/análise , Adsorção , Compostos Ferrosos , Poluentes Químicos da Água/análise
11.
J Med Chem ; 67(10): 8460-8472, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38717104

RESUMO

Recognizing the significance of SPECT in nuclear medicine and the pivotal role of fibroblast activation protein (FAP) in cancer diagnosis and therapy, this study focuses on the development of 99mTc-labeled dimeric HF2 with high tumor uptake and image contrast. The dimeric HF2 was synthesized and radiolabeled with 99mTc in one pot using various coligands (tricine, TPPTS, EDDA, and TPPMS) to yield [99mTc]Tc-TPPTS-HF2, [99mTc]Tc-EDDA-HF2, and [99mTc]Tc-TPPMS-HF2 dimers. SPECT imaging results indicated that [99mTc]Tc-TPPTS-HF2 exhibited higher tumor uptake and tumor-to-normal tissue (T/NT) ratio than [99mTc]Tc-EDDA-HF2 and [99mTc]Tc-TPPMS-HF2. Notably, [99mTc]Tc-TPPTS-HF2 exhibited remarkable tumor accumulation and retention in HT-1080-FAP and U87-MG tumor-bearing mice, thereby surpassing the monomeric [99mTc]Tc-TPPTS-HF. Moreover, [99mTc]Tc-TPPTS-HF2 achieved acceptable T/NT ratios in the hepatocellular carcinoma patient-derived xenograft (HCC-PDX) model, which provided identifiable contrast and imaging quality. In conclusion, this study presents proof-of-concept research on 99mTc-labeled FAP inhibitor dimers for the visualization of multiple tumor types. Among these candidate compounds, [99mTc]Tc-TPPTS-HF2 showed excellent clinical potential, thereby enriching the SPECT tracer toolbox.


Assuntos
Compostos de Organotecnécio , Tomografia Computadorizada de Emissão de Fóton Único , Animais , Humanos , Camundongos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Compostos de Organotecnécio/química , Compostos de Organotecnécio/farmacocinética , Compostos de Organotecnécio/síntese química , Linhagem Celular Tumoral , Desenho de Fármacos , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/farmacocinética , Tecnécio/química , Distribuição Tecidual , Dimerização , Camundongos Nus , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Proteínas de Membrana/química , Endopeptidases/metabolismo , Serina Endopeptidases/metabolismo , Serina Endopeptidases/química
12.
J Med Chem ; 67(10): 8361-8371, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38726551

RESUMO

Due to the complex heterogeneity in different cancer types, the heterodimeric strategy has been intensively practiced to improve the effectiveness of tumor diagnostics. In this study, we developed a series of novel 18F-labeled biotin/FAPI-conjugated heterobivalent radioligands ([18F]AlF-NSFB, [18F]AlF-NSFBP2, and [18F]AlF-NSFBP4), synergistically targeting both fibroblast activation protein (FAP) and biotin receptor (BR), to enhance specific tumor uptake and retention. The in vitro and in vivo biological properties of these dual-targeting tracers were evaluated, with a particular focus on positron emission tomography imaging in A549 and HT1080-FAP tumor-bearing mice. Notably, in comparison to the corresponding FAP-targeted monomer [18F]AlF-NSF, biotin/FAPI-conjugated heterodimers exhibited a high uptake in tumor and prolong retention. In conclusion, as a proof-of-concept study, the findings validated the superiority of biotin/FAPI-conjugated heterodimers and the positive influence of biotin and linker on pharmacokinetics of radioligands. Within them, the bispecific [18F]AlF-NSFBP4 holds significant promise as a candidate for further clinical translational studies.


Assuntos
Biotina , Radioisótopos de Flúor , Animais , Humanos , Radioisótopos de Flúor/química , Biotina/química , Biotina/farmacocinética , Camundongos , Desenho de Fármacos , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/farmacologia , Tomografia por Emissão de Pósitrons , Camundongos Nus , Distribuição Tecidual , Dimerização , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C
13.
Aesthetic Plast Surg ; 37(2): 445-53, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23404449

RESUMO

BACKGROUND: Human facial aesthetics relies on the classification of facial features and standards of attractiveness. However, there are no widely accepted quantitative criteria for facial attractiveness, particularly for Chinese Han faces. Establishing quantitative standards of attractiveness for facial landmarks within facial types is important for planning outcomes in cosmetic plastic surgery. The aim of this study was to determine quantitatively the criteria for attractiveness of eight female Chinese Han facial types. METHODS: A photographic database of young Chinese Han women's faces was created. Photographed faces (450) were classified based on eight established types and scored for attractiveness. Measurements taken at seven standard facial landmarks and their relative proportions were analyzed for correlations to attractiveness scores. Attractive faces of each type were averaged via an image-morphing algorithm to generate synthetic facial types. Results were compared with the neoclassical ideal and data for Caucasians. RESULTS: Morphological proportions corresponding to the highest attractiveness scores for Chinese Han women differed from the neoclassical ideal. In our population of young, normal, healthy Han women, high attractiveness ratings were given to those with greater temporal width and pogonion-gonion distance, and smaller bizygomatic and bigonial widths. As attractiveness scores increased, the ratio of the temporal to bizygomatic widths increased, and the ratio of the distance between the pogonion and gonion to the bizygomatic width also increased slightly. Among the facial types, the oval and inverted triangular were the most attractive. CONCLUSION: The neoclassical ideal of attractiveness does not apply to Han faces. However, the proportion of faces considered attractive in this population was similar to that of Caucasian populations. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Povo Asiático/classificação , Beleza , Face/anatomia & histologia , Ossos Faciais/anatomia & histologia , Adolescente , Adulto , Bases de Dados Factuais , Expressão Facial , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Fotografação , Estudos de Amostragem , Cirurgia Plástica , Percepção Visual , Adulto Jovem
14.
Zhonghua Yi Xue Za Zhi ; 93(32): 2545-8, 2013 Aug 27.
Artigo em Chinês | MEDLINE | ID: mdl-24351593

RESUMO

OBJECTIVE: To explore the value of on-pump beating-heart coronary artery bypass grafting (OnP-BH CABG) for left-main patients with coronary heart disease through a comparative study with conventional coronary artery bypass grafting (CCABG). METHODS: The clinical data were retrospectively analyzed for 66 patients of OnP-BH and 48 control cases undergoing CCABG from January 2009 to January 2012 at Department of Cardiac Surgery, People's Hospital of Zhengzhou University. RESULTS: OnP-BH group had a better clinical outcome than CCABG group. There were obvious statistical difference in cardiopulmonary bypass (CPB) time, mean ventilation time, intensive care unit stay and recovery time of plasma cardiac troponin I (OnP-BH group vs CCABG group:(89 ± 25) vs (117 ± 28) min, (15 ± 14) vs (27 ± 19) h, (57 ± 27) vs (79 ± 34) h, (6.2 ± 1.8) vs (7.0 ± 2.4) d, all P < 0.05). The data of preoperative cTnI showed no significant difference between two groups (P > 0.05) .However, after CPB, significant intergroup difference existed in the level of cTnI (µg/L) OnP-BH group vs CCABG group: (0.5 h after CPB: (0.132 ± 0.022) vs (0.265 ± 0.014) , 1 h after CPB: (0.341 ± 0.027) vs (0.572 ± 0.046) , 1 h after operation: (0.641 ± 0.036) vs (0.932 ± 0.047) , 6 h after operation: (1.212 ± 0.765) vs (1.627 ± 0.542) and 24 h after operation: (1.496 ± 0.263) vs (1.734 ± 0.328) , all P < 0.05). CONCLUSIONS: On-pump beating-heart coronary artery bypass grafting is a feasible surgical approach for left-main patients. And it has a low risk and causes less myocardial damage.


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Doença da Artéria Coronariana/cirurgia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
Waste Manag ; 172: 117-126, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37913689

RESUMO

Membrane concentrated landfill leachate has been characterized by complex component and degradation resistant. In this work, a new catalytic ceramic membrane (CuCM) was developed by in-situ integrating copper oxide in the membrane and used in combination with peroxymonosulfate (PMS) for leachate concentrate treatment. The performance and key factors of the CuCM/PMS system were systematically studied. Results showed that the CuCM/PMS system experienced promising efficiency in the pH range of 3 âˆ¼ 11. The highest COD, TOC, UV254 and Color removal efficiency achieved by the CuCM-3/PMS system under the conditions of pH = 7.0 and CPMS = 10 mM, which reached up to 63.4%, 50.5%, 75.1% and 90.2%, respectively. The possible mechanism of leachate remediation was proposed and non-free radicals (Cu(Ⅲ), 1O2) played an important role in the CuCM/PMS system for leachate remediation. The fluorescence spectrum and GC-MS analysis showed that the refractory organics with a high molecular weight in the leachate concentrate were mostly oxidized into small molecules, which also alleviated the membrane fouling. In addition, the slight decrease in COD (7.4%) and TOC (9.7%) after 6 cycles revealed the good catalytic stability and reusability of CuCM-3/PMS. This work provides a feasible strategy for leachate concentrate remediation via a nonradical oxidation process.


Assuntos
Peróxidos , Poluentes Químicos da Água , Oxirredução , Cerâmica , Poluentes Químicos da Água/análise
16.
Environ Technol ; 44(10): 1478-1492, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34762002

RESUMO

A series of Zn-Al Layered Double Oxides (ZnAl-LDO) composites were prepared by the hydrothermal and calcination method via employing the Zn-Al Layered Double Hydroxide (ZnAl-LDH) as the precursors in the present study. The structural properties and the catalytic ozonation activity of ZnrAl-T composites synthesized with different Zn/Al molar ratios and calcination temperatures were systematically investigated. Diversified characterizations were applied to analyze the phase structure and chemical composition of ZnrAl-T composites. As the calcination temperature increased, the layered ZnAl-LDH structure could be entirely destroyed and the crystallinity gradually improved. With the Zn/Al mole ratio of 4.0 and calcination temperature of 500°C, the Zn4Al-500 composite obtained the outstanding catalytic ozonation performance for atrazine (ATZ) degradation with the pseudo-first-order constant of 0.5080 min-1, which was 5 times more than that in O3 alone. Meanwhile, the ATZ degradation efficiency was gradually enhanced from 44.1% to 99.9% within 3.0 min when the solution pH ranged from 3.0 to 10.0. Besides, the Zn4Al-500 composite exhibited splendid stability over multiple reaction cycles. In addition, the radical scavenging test and electron spin resonance measurement demonstrated that superoxide radical and hydroxyl radical are the dominant reactive species in O3/Zn4Al-500 process. Moreover, nineteen and ten transformation products were detected in O3 alone and O3/Zn4Al-500 process, and possible degradation pathways of ATZ were further elucidated. Overall, the Zn4Al-500 composite would provide a potential alternative for pollutants removal due to its high catalytic ozonation efficiency, stability, and reusability.


Assuntos
Atrazina , Ozônio , Poluentes Químicos da Água , Óxidos/química , Atrazina/química , Ozônio/química , Poluentes Químicos da Água/química , Catálise , Zinco
17.
Environ Sci Pollut Res Int ; 30(11): 30122-30129, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36427131

RESUMO

Cr(III) complexes are typical pollutants in various industrial wastewater and pose a serious threat to the ecosystem and humans. The coagulation process is commonly used in water treatment plants, yet its removal characteristic and mechanism toward Cr(III) complexes have been rarely reported. In this study, the Fe(III) coagulation process was adopted for the evaluation of Cr(III) complex removal in terms of Cr residual concentration as well as floc size. The results showed that Fe(III) with a dose of 0.8 mM removed more than 80% of total Cr for Cr3+ and Cr(III)-acetate, whereas poor removal rate (~ 50%) was obtained for Cr(III)-citrate under the same conditions. Neutral and alkaline conditions facilitated Cr(III)-acetate removal by Fe(III) coagulation, while limited influence was observed for Cr(III)-citrate with various pH. The main removal mechanism of Cr(III)-acetate was precipitation. Cr(III)-citrate elimination largely relied on the adsorption property and sweeping effect of Fe floc. Moreover, Cr(III)-acetate was easier to be separated from a solution since the generated floc sizes were 270 µm. Flocs that formed in the Cr(III)-citrate treatment were only 0.3 µm, resulting in separation difficulties during the coagulation process. The presence of Cr(III)-acetate and Cr(III)-citrate caused a significant decline in membrane flux. This study provided fundamental knowledge of Fe coagulation treatment in Cr(III) complex-containing wastewater.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Humanos , Águas Residuárias , Compostos Férricos/química , Sais , Ecossistema , Citratos , Ácido Cítrico , Acetatos , Purificação da Água/métodos , Poluentes Químicos da Água/química , Cromo/química
18.
Environ Sci Pollut Res Int ; 30(6): 15158-15169, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36166122

RESUMO

Extensive use of antibiotics in the world will cause potential risks to human health and ecosystems. The removal of these antibiotics has attracted much attention. Composite materials are growing attention for diverse pollutants separation and removal based on their specific functionality and surface area. In this study, a series of N-vinylpyrrolidone-divinylbenzene polymers (NVPD) with different N-vinylpyrrolidone (NVP) contents were facilely prepared for the adsorption of tetracycline (TC). The effect of polymer surface properties and aqueous solution chemistry (pH, ionic strength, humic acid) on TC adsorption was further studied. The dynamic adsorption and regeneration experiments were also assessed. The results showed that only 25% of NVP was involved in the reaction. When NVP dosage (%) was 75%, polymer (NVPD-g) owned the largest BET surface area (613.23 m2/g) and obtained the maximum TC adsorption capacities (258.76 mg/g). In the kinetic, the adsorption between TC and polymers with NVP was controlled by chemical adsorption and intra-particle diffusion. The TC adsorption process of NVPD-g depended on the contribution of the hydrophobic effect, electrostatic interactions, H-bonding, π-π electron donor-acceptor (EDA) interactions, and cation-π bonding. Moreover, the removal efficiency of TC by NVPD-g was enhanced in the presence of humic acid (HA) in the dynamic adsorption and 1197 BV (2394 mL) of TC simulated wastewater can be treated. These findings suggest that NVPD-g has a potential application in the purification of TC.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Humanos , Substâncias Húmicas , Adsorção , Ecossistema , Poluentes Químicos da Água/química , Purificação da Água/métodos , Antibacterianos/química , Tetraciclina/química , Água/química , Cinética , Concentração de Íons de Hidrogênio
19.
Environ Sci Pollut Res Int ; 30(27): 70054-70064, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37147539

RESUMO

In this study, Congo red (CR) was degraded by different particle sizes of zero-valent copper (ZVC) activated persulfate (PS) under mild temperature. The CR removal by 50 nm, 500 nm, 15 µm of ZVC activated PS was 97%, 72%, and 16%, respectively. The co-existence of SO42- and Cl- promoted the degradation of CR, and HCO3- and H2PO4- were detrimental to the degradation. With the reduction of ZVC particle size, the effect of coexisting anions on degradation grew stronger. The high degradation efficiency of 50 nm and 500 nm ZVC was achieved at pH=7.0, while the high degradation of 15 µm ZVC was achieved at pH=3.0. It was more favorable to leach copper ions for activating PS to generate reactive oxygen species (ROS) with the smaller particle size of ZVC. The radical quenching experiment and electron paramagnetic resonance (EPR) analysis indicated that SO4-•, •OH and •O2- existed in the reaction. The mineralization of CR reached 80% and three possible paths were suggested for the degradation. Moreover, the degradation of 50 nm ZVC can still reach 96% in the 5th cycle, indicating promising application potential in dyeing wastewater treatment.


Assuntos
Cobre , Poluentes Químicos da Água , Vermelho Congo , Tamanho da Partícula , Poluentes Químicos da Água/análise , Oxirredução
20.
RSC Adv ; 13(25): 17436-17448, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37313519

RESUMO

Catalytic ceramic membranes (CMs) integrated with different metal oxides were designed and fabricated by an impregnation-sintering method. The characterization results indicated that the metal oxides (Co3O4, MnO2, Fe2O3 and CuO) were uniformly anchored around the Al2O3 particles of the membrane basal materials, which could provide a large number of active sites throughout the membrane for the activation of peroxymonosulfate (PMS). The performance of the CMs/PMS system was evaluated by filtrating a phenol solution under different operating conditions. All the four catalytic CMs showed desirable phenol removal efficiency and the performance was in order of CoCM, MnCM, FeCM and CuCM. Moreover, the low metal ion leaching and high catalytic activity even after the 6th run revealed the good stability and reusability of the catalytic CMs. Quenching experiments and electron paramagnetic resonance (EPR) measurements were conducted to discuss the mechanism of PMS activation in the CMs/PMS system. The reactive oxygen species (ROS) were supposed to be SO4˙- and 1O2 in the CoCM/PMS system, 1O2 and O2˙- in the MnCM/PMS system, SO4˙- and ·OH in the FeCM/PMS system, and SO4˙- in the CuCM/PMS system, respectively. The comparative study on the performance and mechanism of the four CMs provides a better understanding of the integrated PMS-CMs behaviors.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA