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1.
Environ Res ; 251(Pt 1): 118613, 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38432570

RESUMEN

The contamination of sediments by toxic metals poses a significant threat to both river ecosystems and human health. In this study, the geo-accumulation index (Igeo), biotoxicity evaluation method, and potential ecological risk index (RI) were employed to analyze the contamination level, biotoxicity risk, and potential ecological risk of toxic metals in surface sediments of the Xiaoqing River. To identify toxic metal sources, Spearman correlation and principal component analysis with multiple linear regression analysis (PCA-MLR) were employed. Additionally, redundancy analysis (RDA) was utilized to investigate potential driving factors affecting toxic metal accumulation in sediments. The results revealed that the levels of the five investigated metals (Cr, Pb, As, Hg, and Cd) showed constant fluctuations during the period 1996-2020. The midstream was found to be more polluted than the upstream and downstream. In the research area, Hg was identified as the primary contaminant with high levels of contamination, posing a biotoxicity risk and potential ecological risk. Pollution sources were identified for two periods: A (1996-2010) and B (2011-2020), with industrial, agricultural, traffic, and natural sources being the main contributors. During period A, industrial sources accounted for the highest proportion (40.8%), followed by agricultural sources (36.6%), and geological natural sources (22.6%). During period B, agricultural sources accounted for the highest proportion (42%), followed by industrial and traffic sources (32.4%), and geological natural sources (25.6%). The distribution of toxic metals in the basin was significantly influenced by water pH, sediment organic matter, population density, and per capita GDP. The study results provide fundamental data for preventing pollution and managing water resources contaminated with toxic metals in the sediments of the Xiaoqing River in Jinan. Additionally, it serves as a reference for analyzing related ecological and environmental issues in the basin.

2.
Angew Chem Int Ed Engl ; 63(9): e202317876, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38193266

RESUMEN

Constructing uniform covalent organic framework (COF) film on substrates for electronic devices is highly desirable. Here, a simple and mild strategy is developed to prepare them by polymerization on a solid-liquid interface. The universality of the method is confirmed by the successful preparation of five COF films with different microstructures. These films have large lateral size, controllable thickness, and high crystalline quality. And COF patterns can also be directly achieved on substrates via hydrophilic and hydrophobic interface engineering, which is in favor of preparing device array. For application studies, the PyTTA-TPA (PyTTA: 4,4',4'',4'''-(1,3,6,8-Tetrakis(4-aminophenyl)pyrene and TPA: terephthalaldehyde) COF film has a high photoresponsivity of 59.79 µA W-1 at 420 nm for photoelectrochemical (PEC) detection. When employed as an active material for optoelectronic synaptic devices for the first attempt, it shows excellent light-stimulated synaptic plasticity properties such as short-term plasticity (STP), long-term plasticity (LTP), and the conversion of STP to LTP, which can be used to simulate biological synaptic functions.

3.
J Am Chem Soc ; 145(49): 26900-26907, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38010167

RESUMEN

The manipulation of topological architectures in two-dimensional (2D) covalent organic framework (COF) materials for different applications is promising but remains a great challenge. Here, we first report the topology-selective synthesis of two distinct varieties of 2DCOFs, imine-based HT-COFs and benzimidazole-fused BI-HT-COFs, by simply altering acid catalysts. To HT-COFs, a superlattice of 1D channel with a persistent triangular shape is formed via Schiff base reaction, while to BI-HT-COFs, a hexagonal lattice structure with a highly conjugated structure and imidazole linkages is constructed due to an imine-based cyclization reaction. The two COFs exhibited marked differences in their bandgap, chemical stability, molecular adsorption, and catalytic activity, which make them have different fields of application. This work not only diversifies the hexaaminotriphenylene-based 2DCOF topologies but also provides vivid examples of structure-property relationships, which would facilitate fundamental research and potential applications of 2DCOFs.

4.
Environ Sci Pollut Res Int ; 30(52): 112445-112461, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37831261

RESUMEN

The accumulation of heavy metals in river sediment poses a major threat to ecological safety. The Xiaoqing River originates in western Jinan, with higher population density and per capita gross domestic product (GDP) in its basin compared to the Shandong province average. This study analyzed the spatial characteristics, ecological risk, human health risk, and contamination sources of heavy metals by collecting sediment samples from Xiaoqing River. We use the methods such as geo-accumulation index (Igeo), ecological risk assessment based on the interval number sorting method, and health risk assessment to evaluate the risk of heavy metals in sediments. The research finding suggests heavy metals including Pb, As, Ni, and Cr are low ecological risks, while Hg and Cd have reached high and extreme ecological risks. Correlation analysis and principal component analysis were used to analyze the correlation and sources of different heavy metals. The six heavy metals were categorized into three groups. Factor 1, comprising Hg, Cr, and Pb, was identified as a mixed source with a contribution rate of 37.76%. Factor 2 is an agricultural source and comprises Ni, Cd, and As with a contribution rate of 27.05%. Factor 3 includes Pb and Ni contributing to 15.30% as a natural source. This study offers valuable insights for the prevention of heavy metal pollution, as well as promoting sustainable urban development.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes Químicos del Agua , Humanos , Monitoreo del Ambiente/métodos , Ríos , Cadmio/análisis , Plomo/análisis , Sedimentos Geológicos/análisis , Contaminantes Químicos del Agua/análisis , Metales Pesados/análisis , Medición de Riesgo , Mercurio/análisis , China
5.
PLoS Biol ; 21(9): e3002256, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37708089

RESUMEN

The eradication of cancer stem cells (CSCs) with drug resistance confers the probability of local tumor control after chemotherapy or targeted therapy. As the main drug resistance marker, ABCG2 is also critical for colorectal cancer (CRC) evolution, in particular cancer stem-like traits expansion. Hitherto, the knowledge about the expression regulation of ABCG2, in particular its upstream transcriptional regulatory mechanisms, remains limited in cancer, including CRC. Here, ABCG2 was found to be markedly up-regulated in CRC CSCs (cCSCs) expansion and chemo-resistant CRC tissues and closely associated with CRC recurrence. Mechanistically, TOX3 was identified as a specific transcriptional factor to drive ABCG2 expression and subsequent cCSCs expansion and chemoresistance by binding to -261 to -141 segments of the ABCG2 promoter region. Moreover, we found that TOX3 recruited WDR5 to promote tri-methylation of H3K4 at the ABCG2 promoter in cCSCs, which further confers stem-like traits and chemoresistance to CRC by co-regulating the transcription of ABCG2. In line with this observation, TOX3, WDR5, and ABCG2 showed abnormal activation in chemo-resistant tumor tissues of in situ CRC mouse model and clinical investigation further demonstrated the comprehensive assessment of TOX3, WDR5, and ABCG2 could be a more efficient strategy for survival prediction of CRC patients with recurrence or metastasis. Thus, our study found that TOX3-WDR5/ABCG2 signaling axis plays a critical role in regulating CRC stem-like traits and chemoresistance, and a combination of chemotherapy with WDR5 inhibitors may induce synthetic lethality in ABCG2-deregulated tumors.


Asunto(s)
Neoplasias Colorrectales , Resistencia a Antineoplásicos , Animales , Ratones , Resistencia a Antineoplásicos/genética , Modelos Animales de Enfermedad , Conocimiento , Células Madre Neoplásicas , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética
6.
ACS Appl Mater Interfaces ; 15(13): 16991-16998, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36972375

RESUMEN

Two-dimensional (2D) conjugated metal-organic framework (c-MOF) films bring a completely new opportunity in the fields of catalysis, energy, and sensors, but preparing large-area continuous 2D c-MOF films remains a tremendous challenge. Here, we report a universal recrystallization strategy to synthesize large-area continuous 2D c-MOF films, revealing that the recrystallization strategy can significantly improve the electrochemical sensor sensitivity. Applying the 2D Cu3(HHTP)2 (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) c-MOF film as the active layer, the electrochemical sensor for glucose detection shows a high sensitivity of 20600 µA mM-1 cm-2, which is the best compared with the active materials reported previously. Most importantly, the as-made Cu3(HHTP)2 c-MOF-based electrochemical sensor possesses excellent stability. Overall, this work brings a brand-new universal strategy to prepare large-area continuous 2D c-MOF films for electrochemical sensors.

7.
Cancer Sci ; 114(6): 2277-2292, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36786527

RESUMEN

The mediator complex usually cooperates with transcription factors to be involved in RNA polymerase II-mediated gene transcription. As one component of this complex, MED27 has been reported in our previous studies to promote thyroid cancer and melanoma progression. However, the precise function of MED27 in breast cancer development remains poorly understood. Here, we found that MED27 was more highly expressed in breast cancer samples than in normal tissues, especially in triple-negative breast cancer, and its expression level was elevated with the increase in pathological stage. MED27 knockdown in triple-negative breast cancer cells inhibited cancer cell metastasis and stemness maintenance, which was accompanied by downregulation of the expression of EMT- and stem traits-associated proteins, and vice versa in non-triple-negative breast cancer. Furthermore, MED27 knockdown sensitized breast cancer cells to epirubicin treatment by inducing cellular apoptosis and reducing tumorsphere-forming ability. Based on RNA-seq, we identified KLF4 as the possible downstream target of MED27. KLF4 overexpression reversed the MED27 silencing-mediated arrest of cellular metastasis and stemness maintenance capacity in breast cancer in vitro and in vivo. Mechanistically, MED27 transcriptionally regulated KLF4 by binding to its promoter region at positions -156 to +177. Collectively, our study not only demonstrated the tumor-promoting role of MED27 in breast cancer progression by transcriptionally targeting KLF4, but also suggested the possibility of developing the MED27/KLF4 signaling axis as a potential therapeutic target in breast cancer.


Asunto(s)
Neoplasias Mamarias Animales , Neoplasias de la Mama Triple Negativas , Humanos , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Neoplasias Mamarias Animales/genética , Complejo Mediador/genética , Complejo Mediador/metabolismo , Transducción de Señal , Neoplasias de la Mama Triple Negativas/genética
8.
Eur J Med Res ; 27(1): 299, 2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36529788

RESUMEN

PURPOSE: VEGF facilitates tumor angiogenesis, and bevacizumab targeting VEGF is used in anti-tumor therapy. It is meaningful to clarify the upstream regulatory mechanism of VEGF. BPTF is important in chromosomal remodeling, and promotes the progression of tumors. However, its role in promoting tumor angiogenesis by targeting VEGF has not been fully reported. This study aims to elucidate the expression regulation of VEGF by BPTF and its clinical significance in NSCLC. METHODS: 1. BPTF siRNA and shRNA plasmids were used to reduce the expression of BPTF by transfection in vivo and in vitro. BPTF, VEGF and CD144 expressions were examined by immunofluorescence and Western Blot. 2. The expressions of BPTF, VEGF, CD144 and CD31 were detected in lung adenocarcinoma samples by immunofluorescence, Western blot and immunohistochemical staining. 3. 26 lung adenocarcinoma patients treated by bevacizumab were divided into 2 groups according to the treatment efficacy. BPTF and VEGF expressions were analyzed. RESULTS: 1. BPTF knockdown inhibited the expression of VEGF and CD144 in vivo and in vitro. 2. Compared with para-cancer tissues, BPTF, VEGF, CD144 and CD31 were highly expressed in lung adenocarcinoma. 3. In 75 lung adenocarcinoma specimens, BPTF and VEGF overexpression was correlated with lymph node metastasis and clinical stage. The 5-year survival rate of patients with BPTF and VEGF low expression was higher, and BPTF expression was positively correlated with VEGF expression. 4. Among 26 patients treated with bevacizumab, the patients with BPTF overexpression are more sensitive to the treatment. CONCLUSIONS: BPTF positively regulates VEGF expression and its high expression predicts a better efficacy of bevacizumab treatment in NSCLC.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Bevacizumab/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Relevancia Clínica , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Proteínas del Tejido Nervioso , ARN Interferente Pequeño , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
9.
Redox Biol ; 55: 102418, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35932692

RESUMEN

As the largest subunit of the nuclear remodeling factor complex, Bromodomain PHD Finger Transcription Factor (BPTF) has been reported to be involved in tumorigenesis and development in several cancers. However, to date, its functions and related molecular mechanisms in colorectal cancer (CRC) are still poorly defined and deserve to be revealed. In this study, we uncovered that, under the expression regulation of c-Myc, BPTF promoted CRC progression by targeting Cdc25A. BPTF was found to be highly expressed in CRC and promoted the proliferation and metastasis of CRC cells through BPTF specific siRNAs, shRNAs or inhibitors. Based on RNA-seq, combined with DNA-pulldown, ChIP and luciferase reporter assay, we proved that, by binding to -178/+107 region within Cdc25A promoter, BPTF transcriptionally activated Cdc25A, thus accelerating the cell cycle process of CRC cells. Meanwhile, BPTF itself was found to be transcriptionally regulated by c-Myc. Moreover, BPTF knockdown or inactivation was verified to sensitize CRC cells to chemotherapeutics, 5-Fluorouracil (5FU) and Oxaliplatin (Oxa), c-Myc inhibitor and cell cycle inhibitor not just at the cellular level in vitro, but in subcutaneous xenografts or AOM/DSS-induced in situ models of CRC in mice, while Cdc25A overexpression partially reversed BPTF silencing-caused tumor growth inhibition. Clinically, BPTF, c-Myc and Cdc25A were highly expressed in CRC tissues simultaneously, the expression of any two of the three was positively correlated, and their expressions were highly relevant to tumor differentiation, TNM staging and poor prognosis of CRC patients. Thus, our study indicated that the targeted inhibition of BPTF alone, or together with chemotherapy and/or cell cycle-targeted therapy, might act as a promising new strategy for CRC treatment, while c-Myc/BPTF/Cdc25A signaling axis is expected to be developed as an associated set of candidate biomarkers for CRC diagnosis and prognosis prediction.

10.
Free Radic Biol Med ; 177: 31-47, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34648907

RESUMEN

In spite of significant advances in the understanding of glioma biology and pathology, survival remains poor. Therefore, it is still of great significance to further explore the key factors involved in tumorigenesis and development in glioma and find potential new therapeutic targets. Here, we show that thyroid hormone receptor interactor 4 (TRIP4) is highly expressed in glioma cells and tissues. Patients of glioma with high expression of TRIP4 possess poor overall survival. Knockdown of TRIP4 inhibited tumor cell proliferation, metastasis, and apoptosis suppression, whereas overexpression of TRIP4 displays the opposite effects. Further research showed that TRIP4 promoted glioma progression through regulating DDIT4 expression and subsequent activation of mTOR signaling. DDIT4 overexpression restored the inhibition of tumor growth by TRIP4 knockdown in vitro and in vivo. Consistently, mTOR activity inhibition reversed TRIP4 overexpression-mediated tumor promotion in vitro and in vivo. Moreover, molecular mechanism exploration demonstrates that TRIP4 functions as a specific transcriptional activator to anchor at the promoter region of DDIT4 gene (-196 to -11) to regulate its transcription and such regulation was affected by HIF1α. Clinically, TRIP4 expression is positively correlated with DDIT4 expression in glioma samples based on tissue microarray analysis and both of their high expression predicts the malignancy of the disease. Altogether, our findings identify TRIP4 as a critical promoter of glioma progression by targeting DDIT4 and mTOR signaling successively and suggest that TRIP4-DDIT4 axis has potential to be a novel therapeutic target in glioma treatment.


Asunto(s)
Glioma , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Humanos , Transducción de Señal , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Factores de Transcripción
11.
Waste Manag ; 136: 36-46, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34637977

RESUMEN

With the massive use of plastic products, plastic pollution has increasingly attracted worldwide attention. To deal with the problem of plastic pollution, the Chinese government issued the "Opinions on Further Strengthening the Control of Plastic Pollution" (Abbreviated as OFSCPP), which is known as "plastic restriction policy" by the public, in January 2020. It stipulates the timetable and main tasks for restricting the production, sales, and use of certain plastic products, such as plastic bags, disposable straws and agricultural mulch. Since the policy was officially implemented on January 1, 2021, people's lives in China have been considerably affected, and it has also attracted widespread attention from news media. In this study, 310 pieces of news items and information about the OFSCPP published in the first quarter of 2021 from the Baidu News website from which 44, 94, 90, 26, and 49 statements from producers, retailers, consumers, managers, and experts were extracted. The extracted words and expressions were then analyzed using the Latent Dirichlet Allocation topic model. Text analysis results showed that the production efficiency of plastic substitutes in China cannot meet market demand, consumers' experience on plastic substitutes is poor, and recycling and disposal processing information is opaque. To achieve the policy goals, the government should encourage the innovation of high-quality and inexpensive plastic alternatives, the national standards for plastic substitutes should be urgently improved, consumers' concept of green consumption should be gradually cultivated, and terminal recycling and disposal should be promoted.


Asunto(s)
Plásticos , Reciclaje , China , Minería de Datos , Humanos , Políticas
12.
Sci Total Environ ; 769: 145158, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33485207

RESUMEN

Coronavirus disease 2019 (COVID-19) is a global pandemic and a major health emergency. In the process of fighting against COVID-19, the China Ministry of Ecology and Environment (MEE) responded quickly and set up a working group as soon as possible. This article uses text mining to retrospectively analyze the government's public information on the website of MEE during the epidemic, sort out the timeline of MEE's response to COVID-19. We find that MEE's work during the COVID-19 pandemic is focused on medical waste and wastewater treatment, environment emergency monitoring, pollution prevention, and other environmental management for supporting economic recovery. It drafted three main medical waste management plans, an emergency environmental monitoring plan, and formulated "two lists" - a Positive checklist for Environmental impact assessment (EIA) approval and a positive checklist for supervision and enforcement, to promote the resumption of work and production. 2020 is the final year of China's "three years of fighting pollution prevention and control". In the case of the sudden COVID-19 epidemic, the Chinese environment department has ensured that the quality of the ecological environment has not been affected by the epidemic prevention and control while ensuring the smooth progress of the fight against pollution. China's medical waste disposal capacity has also been greatly improved during this epidemic. The review of China's environmental management strategy in response to COVID-19 can provide a reference for countries in the world that are still in the critical period of epidemic control; it can provide action guidelines for the ecological environment system to respond to sudden pandemic events in the future.


Asunto(s)
COVID-19 , Pandemias , China/epidemiología , Conservación de los Recursos Naturales , Minería de Datos , Gobierno , Humanos , Estudios Retrospectivos , SARS-CoV-2
13.
Mol Oncol ; 15(4): 1180-1202, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33305480

RESUMEN

Human telomerase reverse transcriptase (hTERT) plays an extremely important role in cancer initiation and development, including colorectal cancer (CRC). However, the precise upstream regulatory mechanisms of hTERT in different cancer types remain poorly understood. Here, we uncovered the candidate transcriptional factor of hTERT in CRC and explored its role and the corresponding molecular mechanisms in regulating hTERT expression and CRC survival with an aim of developing mechanism-based combinational targeting therapy. The possible binding proteins at the hTERT promoter were uncovered using pull-down/mass spectrometry analysis. The regulation of SPT6 on hTERT expression and CRC survival was evaluated in human CRC cell lines and mouse models. Mechanistic studies focusing on the synergy between SPT6 and staphylococcal nuclease and Tudor domain containing 1 (SND1) in controlling hTERT expression and CRC progression were conducted also in the above two levels. The expression correlation and clinical significance of SPT6, SND1, and hTERT were investigated in tumor tissues from murine models and patients with CRC in situ. SPT6 was identified as a possible transcriptional factor to bind to the hTERT promoter. SPT6 knockdown decreased the activity of hTERT promoter, downregulated the protein expression level of hTERT, suppressed proliferation, invasion, and stem-like properties, promoted apoptosis induction, and enhanced chemotherapeutic drug sensitivity in vitro. SPT6 silencing also led to the delay of tumor growth and metastasis in mice carrying xenografts of human-derived colon cancer cells. Mechanistically, SND1 interacted with SPT6 to co-control hTERT expression and CRC cell proliferation, stemness, and growth in vitro and in vivo. SPT6, SND1, and hTERT were highly expressed simultaneously in CRC tissues, both from the murine model and patients with CRC in situ, and pairwise expression among these three factors showed a significant positive correlation. In brief, our research demonstrated that SPT6 synergized with SND1 to promote CRC development by targeting hTERT and put forward that inhibiting the SPT6-SND1-hTERT axis may create a therapeutic vulnerability in CRC.


Asunto(s)
Neoplasias del Colon/patología , Endonucleasas/genética , Telomerasa/metabolismo , Factores de Transcripción/genética , Animales , Línea Celular Tumoral , Neoplasias del Colon/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias , Regiones Promotoras Genéticas
14.
Sci Total Environ ; 708: 134669, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31796270

RESUMEN

Eco-friendly treatment of refractory pollutants in wastewater is still full of challenge in catalytic oxidation and adsorption. In this study, based on the concept of green chemistry, sulfur-doped titanium dioxide hollow spheres modified by surfactant loaded on magnetic bentonite (CST/γ-Fe2O3-BT) is synthesized in two steps, and bisphenol A (BPA) was chosen as the representative organic pollutant. These materials were characterized by means of XRD, FTIR, SEM, EDS, TEM, XPS, BET, and VSM techniques. The adsorption and photodegradation behavior of CST/γ-Fe2O3-BT were examined. The Langmuir isotherm exhibited a better fit with a maximum adsorption capacity of 77.36 mg/g. At pH 7, the reaction rate constant (k) of the BPA photocatalytic degradation by product was 0.00104 min-1, and the adsorption equilibrium constant (K) was 0.04034L/mg. In addition, the composite can be recovered from the reaction mixture by applying an external magnetic field due to the existence of the superparamagnetic iron oxide nanoparticles in the construct. The recovered particles retained their catalytic activity which the catalytic activity of the material still reached 91% of the first catalytic experiment after 5 repetitive experiments. Results infer that the material has excellent reusability. Thus, CST/γ-Fe2O3-BT is a significant candidate for the treatment of recalcitrant organic pollutants in wastewater.

15.
Sci Total Environ ; 682: 505-513, 2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31129538

RESUMEN

Magnetic nano-composite materials have been attracting considerable attention due to their unique properties and versatile applications. In this study, a novel magnetic amino-functionalized conjugate adsorbent, named as bentonite/CoFe2O4@MnO2-NH2 (BCFMNs), was synthesized by combining APTES and MnO2 with magnetic bentonite. XRD, FT-IR, SEM, EDS, TEM, and VSM techniques were used to characterize its structure and magnetic properties. Results were in indicative of productive synthesis, well-defined architecture and satisfactory magnetism. BET examinations illustrated 84.97m2/g of specific surface area, 0.15cm3/g of pore volume and 7.02nm average pore size. The effect parameters such as adsorbent dosage, contact time, initial concentration and ion selectivity and recycling were evaluated and optimized systematically. Also, the metal concentrations were measured by ICP-MS spectrometer. The feasibility of the BCFMNs for removal of Cd2+ from aqueous solution was also evaluated by adsorption experiments with the maximal adsorption efficiency for Cd2+ up to 98.88%. Cd2+ adsorption could be interpreted by the Langmuir adsorption isotherm and the maximum adsorption capacity was 115.79mg/g. The results revealed that the adsorbent still had higher selectivity of Cd2+ removal even in the presence of high concentration coexisting cations. The as-prepared magnetic conjugate adsorbent could be recycled by taking advantage of its magnetic properties. The distinctive structure of BCFMNs and its excellent adsorption performance of cadmium reflects its prospective application in water treatment.

16.
Environ Sci Pollut Res Int ; 25(32): 32321-32331, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30229490

RESUMEN

In the process of excavation and utilization of the coal gangue hill, gangue at different weathering degree was exposed to the environment, which can be harmful to the surroundings. In order to find the law of heavy metal release and to evaluate the potential ecological risk, five kinds of coal gangue at different weathering degrees were collected from a coal mine named Suncun, an over 100-year-old mine of Xinwen coal mining field located in Tai'an city, Shandong Province of China. Samples were processed with microwave digestion for total content determination of heavy metals, and another part of samples was processed by Tessier sequential extraction for chemical forms analysis. Leaching tests at various pH were carried out to investigate the release of heavy metal. The laws of transformation and release of heavy metals were discussed and potential ecological risk was evaluated. The results indicated that the weathering degree had a significant impact on the content of heavy metal. Exchangeable and carbonate fractions of Cr and Pb were a large proportion of the total and should attract great attention. Potential ecological risk was at strong level (light black) and was up to very strong level (deep black) because of Cd. But Cr had contributed the most for gray gangue, which was 71% of the total. The species of heavy metal in gangue changed due to weathering and lead to the difference of the leaching characteristic and risk.


Asunto(s)
Minas de Carbón , Carbón Mineral/análisis , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Aguas Residuales/química , China , Cromo/análisis , Ciudades , Ecología , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/métodos , Plomo/análisis , Riesgo , Medición de Riesgo
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