Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
J Environ Manage ; 315: 115168, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35525047

RESUMO

Magnetic coagulation is a promising approach for treating high phosphorous (high-P) wastewater by enhancing precipitation efficiency using magnetic particles. In this study, a cost-effective and environmentally friendly magnetic seed from coal fly ash (MS-CFA) was used as an alternative material for Fe3O4 magnetic seed (MS) coagulation. The potential effect of MS-CFA was explored to reduce the settling time and the dosage of coagulant aid of polyacrylamide (PAM) in treating high-phosphorous (high-P) simulated wastewater at 100 and 200 mg P/L. The physicochemical characteristics of MS-CFA were analysed through particle size distribution (20-100 µm), pore size distribution (14-30 nm), specific surface area (1.654 m2/g), X-ray diffraction (XRD), specific gravity (4.2), and magnetic induction intensity (49.8 emu/g). The characteristics met the requirements as magnetic coagulation material. MS-CFA was combined with polyaluminum chloride (PAC) and polyacrylamide (PAM) to improve phosphorous precipitation performance. The synergised magnetic coagulation effect using MS-CFA and PAM reduced the settling time of flocs to less than 1 min due to the high specific gravity. This represents a reduction of 90% of the settling time compared to the control using PAM alone (15 min) without MS-CFA. MS-CFA efficiently reduced PAM dosage by 83% and 87% for treating 100 and 200 mg P/L, respectively. The presence of PAM (1 mg/L for 100 mg P/L and 2 mg/L for 200 mg P/L) was imperative for binding the MS-CFA and flocs, hence increasing the particle size of the magnetic flocs. The characteristics of the magnetic flocs were analysed through microscopy, particle size distribution, zeta potential measurements, and magnetic induction intensity. The characteristics of the magnetic flocs confirmed that MS-CFA could be an alternative material for Fe3O4 as the magnetic seeds in the magnetic coagulation process for treating high-P wastewater.


Assuntos
Cinza de Carvão , Águas Residuárias , Carvão Mineral , Fenômenos Magnéticos , Fósforo
2.
J Environ Manage ; 244: 399-407, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31132621

RESUMO

For the low-concentration oily micro-polluted water formed by the leakage of refined oil products, an unexpensive and high-efficiency magnetic enhanced flocculation method was introduced in this study. First, the performance of magnetic flocculation(MF) to remove oily contaminants was discussed. The results indicated that it achieved more than 95% removal in only 1min with 50mg/L-Polyaluminum chloride(PAC), 50mg/L-Fe3O4 and10mg/L- Polyacrylamide (PAM). The novel indexs Rδand Si were proposed to evaluate the oil removal with UV-Abs in-situ method. According to the adsorption kinetics of oil contaminants, the adsorption kinetics changed from pseudo-first-order to pseudo-second-order kinetics after the addition of Fe3O4 on the basis of conventional coagulation (CF). It was transformed into intraparticle diffusion kinetics when the PAM continued to be added. Combined with the Fe-O-Al bond in the FTIR spectrum of flocs, the main mechanism of MF is enhanced charge neutralization and hydrogen bond adsorption. In addition, it was shown that satisfactory oil removal after recover, which indicated the great potential of a sustainable way by reusing low-cost magnetic seeds.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Floculação , Magnetismo , Óleos , Poluição da Água
3.
J Environ Sci (China) ; 81: 4-16, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30975328

RESUMO

Core-shell magnetic seeds with certain adsorption capacity that were prepared by sulfated roasting, served as the core of a magnetic separation technology for purification of starch wastewater. XRD and SEM results indicate that magnetite's surface transformed to be porous α-Fe2O3 structure. Compared with magnetite particles, the specific surface area was significantly improved to be 8.361 from 2.591 m2/g, with little decrease in specific susceptibility. Zeta potential, FT-IR and XPS experiments indicate that both phosphate and starch adsorbed on the surface of the core-shell magnetic seeds by chemical adsorption, which fits well with the Langmuir adsorption model. The porous surface structure of magnetic seeds significantly contributes to the adsorption of phosphate and starch species, which can be efficiently removed to be 1.51 mg/L (phosphate) and 9.51 mg/L (starch) using magnetic separation.


Assuntos
Fósforo/análise , Amido/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Óxido Ferroso-Férrico/química , Magnetismo , Sulfatos/química
4.
Eur J Surg Oncol ; 50(10): 108485, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39047326

RESUMO

BACKGROUND: Localization of non-palpable melanoma, Merkel cell carcinoma (MCC) and soft tissue sarcoma (STS) lesions can be difficult due to size, location, and obesity of patients or fibrosis due to previous treatments. Magnetic seed localization (MSL) is a common method to localize non-palpable breast lesions, but the feasibility of MSL for non-palpable melanoma, MCC and STS lesions has not yet been described. METHODS: In this retrospective single center cohort study, all consecutive patients between January 2021 and October 2023 who had a resection of a non-palpable melanoma, MCC or STS lesion guided by Sirius Pintuition, a MSL technique, were included. The primary endpoint was successful lesion localization during surgery and the secondary endpoints were seed migration, negative resection margins, and complications. RESULTS: Seventy-nine seeds were placed for 76 lesions, which were resected during 68 surgeries in 61 patients. All lesions (100 %) were localized and resected. Median time of surgery was 44 min. No seed migration was observed. A negative resection margin was achieved for 60 (78.9 %) lesions. Clavien Dindo grade ≥2 complications occurred in 7.4 %. CONCLUSION: Magnetic seed localization with Sirius Pintuition is feasible for both non-palpable melanoma, MCC, and STS lesions.


Assuntos
Carcinoma de Célula de Merkel , Estudos de Viabilidade , Melanoma , Sarcoma , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico por imagem , Melanoma/cirurgia , Melanoma/patologia , Feminino , Estudos Retrospectivos , Idoso , Masculino , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/cirurgia , Pessoa de Meia-Idade , Sarcoma/diagnóstico por imagem , Sarcoma/cirurgia , Sarcoma/patologia , Carcinoma de Célula de Merkel/diagnóstico por imagem , Carcinoma de Célula de Merkel/patologia , Carcinoma de Célula de Merkel/cirurgia , Adulto , Idoso de 80 Anos ou mais , Margens de Excisão , Marcadores Fiduciais
5.
Pharmaceutics ; 15(2)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36839964

RESUMO

This article reports on incorporating magnetic nanoparticles into natural carbon frameworks derived from Nigella Sativa seeds and their synthesis via co-precipitation reactions for application in biomedicine. The magnetic Nigella Sativa Seeds (Magnetic NSS), a metal oxide-based bio-nanomaterial, has shown excellent water diaper presence due to the presence of a wide range of oxygenous hydroxyl and carboxyl groups. The physicochemical properties of the composites were characterized extensively using Fourier transform infrared spectroscopy (FTIR), powder-X-ray diffraction (XRD), scanning electron microscopy (SEM), elemental analysis, transmission electron microscopy (TEM), and vibrating-sample magnetometer. Furthermore, synthesized magnetic NSS showed antioxidant and antifungal activity. The antifungal susceptibility was further tested against Candida albicans with a MIC value of 3.125 µg/mL. Analysis of antioxidant defense enzymes was determined quantitatively; the results suggested that antioxidant enzyme activity increase with increased magnetic NSS concentration. Furthermore, biofilm inhibition assay from scanning electron microscopy results revealed that magnetic NSS at the concentration of 3.5 µg/mL has anti-biofilm properties and can disrupt membrane integrity.

6.
Artigo em Inglês | MEDLINE | ID: mdl-35193816

RESUMO

The increasingly early diagnosis of breast disease and the more widespread use of primary systemic therapy leads to an increasing number of surgeries for non-palpable breast lesions (NPL) in clinical practice. Breast-conserving surgery often requires the use of an image-guided preoperative localization procedure, in which a device is placed within the lesion to be removed to guide the surgeon during surgery. These are patients with small, non-palpable tumors detected in the population screening mammogram, cases with significant reduction of the lesion after neoadjuvant chemotherapy and sometimes it is even necessary to mark axillary lymphadenopathies prior to systemic treatment. For decades, wire localization has been the standard for preoperative marking in breast cancer. Due to the external component of this device, extreme care must be taken not to alter its position before surgery, which is why it is placed hours before surgery and entails complex and limited flexibility in surgical programming. Intraoperative ultrasound improves this drawback but has the limitation that it can only be performed in those NPLs that have ultrasound translation. The Radioguided Occult Lesion Localization (ROLL) technique, although it is another alternative adopted by many institutions, is not without complications, among which the possibility of diffusion of the radiotracer into healthy tissue stands out. To overcome these problems, more recently, 125I radioactive seeds began to be used. Subsequently, thanks to technological advances, non-radioactive seed alternatives such as radar reflectors, magnetic seeds and radio frequency markers have emerged. These locating devices can be placed days before surgery, avoiding wire-related problems and complications. They are introduced percutaneously and identified intraoperatively using a detector device. There is no perfect intraoperative localization method for NPL excision, but fortunately, we have multiple techniques with different advantages and disadvantages that must be assessed and adapted to the center's own resources, the type of surgery, and always to the benefit of the patient.


Assuntos
Neoplasias da Mama , Mamografia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Detecção Precoce de Câncer , Feminino , Humanos , Mastectomia Segmentar , Ultrassonografia
7.
Environ Sci Pollut Res Int ; 27(29): 37011-37021, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32577974

RESUMO

A large number of iron ore tailings (IOTs) are produced in steel industry, posing threat to the environment during its storage and disposal. To effectively reutilize Fe in IOTs, we propose a comprehensive utilization scheme: (1) most Fe in IOTs is extracted by concentrated hydrochloric acid to form FeCl3 flocculants; (2) after separation from the FeCl3 flocculants, a small amount of Fe is absorbed on the residue solids, which is further washed out to synthesize micron Fe3O4 as magnetic seeds. Results show that the as-synthetic FeCl3 flocculants meet the product standard for FeCl3 flocculants in China (GB/T 4482-2018) after a series of treatments including rotary evaporation, neutralization, and dilution and have comparable performance with commercial polyaluminum chloride (PAC) and polyaluminum ferric chloride (PAFC). Moreover, the addition of synthetic superparamagnetic Fe3O4 (as magnetic seeds) doubled the flocculation rate compared with as-synthetic FeCl3 flocculants alone. Finally, the reutilization of Fe in IOTs can create a direct economic value of ¥ 1.27/kg IOTs, and produce 745 g high-silicon residues for further reutilization, which indicates that our comprehensive utilization scheme is of great application potential.


Assuntos
Ferro , Magnetismo , China , Floculação , Fenômenos Magnéticos
8.
Anticancer Res ; 40(1): 315-321, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31892582

RESUMO

BACKGROUND: Wire-guided localisation (WGL) remains the most widely used technique to guide surgical excision of non-palpable breast lesions worldwide. However, recent technological advances have led to the advent of less invasive radiation-free localisation methods to overcome the limitations of WGL. PATIENTS AND METHODS: This study prospectively evaluated the role of two radiation-free non-wire localisation methods. Magnetic seeds (n=16) and radiofrequency tags (n=6) were deployed under imaging guidance to guide the surgical excision in 19 consecutive patients. RESULTS: The identification/retrieval and migration rates were 100% and 4.5%, respectively. Twenty-one out of 22 (95.5%) cases had clear surgical margins and no complications were observed. All radiologists and the surgeon rated these methods as being much better than wire localisation. Patient satisfaction data were recorded using a linear visual analogue scale (n=10/19). The mean score was 9.7/10 (range=8-10). CONCLUSION: Our study provides further evidence that radiation-free wireless breast localisation is an effective alternative to WGL.


Assuntos
Neoplasias da Mama/cirurgia , Fenômenos Magnéticos , Mastectomia , Dispositivo de Identificação por Radiofrequência , Adulto , Idoso , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade
9.
In Vivo ; 34(3): 1159-1164, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32354905

RESUMO

BACKGROUND: Exact localization of non-palpable breast lesions is necessary to ensure that the correct lesion is removed. Conventional methods come with several disadvantages. PATIENTS AND METHODS: We compared 28 patients who underwent breast-conserving surgery for a non-palpable lesion. By surgeon choice, 14 patients were assigned to undergo magnetic seed localization and 14 underwent standard wire localization. The primary outcome was the operative time, and secondary outcome was the patient pain level. RESULTS: The mean age was 52±10 (SD) years in the seed arm, and 55±13 years in the wire arm. The median time from skin incision to tumor extraction was not significantly different between the two groups. Patients in the wire localized group significantly more often reported pain during coughing/breathing, movement, and sleep. CONCLUSION: Using seed localization at Charité Breast Center did not lead to a significant decrease in operative time but might allow time savings once established, while increasing patient comfort and reducing organizational burden.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Adulto , Idoso , Neoplasias da Mama/terapia , Diagnóstico por Imagem , Feminino , Humanos , Mamografia/métodos , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Carga Tumoral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA