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Rahmatollah Rahimi Azadeh Tadjarodi Mahboubeh Rabbani Hamed Kerdari Mina Imani 《Journal of Superconductivity and Novel Magnetism》2013,26(1):219-228
In this study, Ba-Cd-Sr-Ti doped Fe3O4 nanohollow spheres were successfully prepared via a simple solvothermal method. The crystal size, structure, morphology and elemental analysis of the as-prepared sample were investigated in detail by X-ray diffraction (XRD), FT-IR, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy, respectively. Magnetic hysteresis measurement was carried out on a vibrant sample magnetometer (VSM) showing the soft ferromagnetic property at room temperature. The synthesized nanohollow spheres were employed as a photocatalyst to study the photocatalytic degradation of dye contaminations. The UV-Vis results showed that the specimen could well catalyze the decolorizing of congo red (CR) solution and a removal efficiency of 99.5 % was obtained at pH 6. The optical characteristic of the products was studied by estimating the band-gap energy based on diffuse-reflectance spectroscopy (DRS) which represented the doped magnetite with semiconductor metals to be more prone in the visible region as compared to UV region. Some factors such as initial dye concentration, pH, and contact time influencing the decomposition of CR were evaluated. 相似文献
43.
Zahra Bakhtiary Jaleh Barar Ayuob Aghanejad Amir Ata Saei Elhameh Nemati 《Drug development and industrial pharmacy》2017,43(8):1244-1253
Non-small cell lung cancer (NSCLC) patients with sensitizing mutations in the exons 18–21 of the epithelial growth factor receptor (EGFR) gene show increased kinase activity of EGFR. Hence, tyrosine kinase inhibitors (TKIs) such as erlotinib (ETB) have commonly been used as the second line therapeutic option for the treatment of metastatic NSCLC. While the ETB is available as an oral dosage form, the local delivery of this TKI to the diseased cells of the lung may ameliorate its therapeutic impacts. In the current study, we report on the development of ETB-loaded solid lipid nanoparticle (SLN) based formulation of dry powder inhaler (ETB-SLN DPI). ETB-SLNs were formulated using designated amount of compritol/poloxamer 407. The engineered ETB-SLNs showed sub-100?nm spherical shape with an encapsulation efficiency of 78.21%. MTT assay and DAPI staining revealed that the ETB-SLNs enhanced the cytotoxicity of cargo drug molecules in the human alveolar adenocarcinoma epithelial A549 cells as a model for NSCLC. To attain the ETB-SLN DPI, the ETB-SLNs were efficiently spray dried into microparticles (1–5?μm) along with mannitol. The ETB-SLN DPI powder displayed suitable flowability and aerodynamic traits. The Carr's Index, Hausner ratio and Next Generation Impactor (NGI) analyses confirmed deep inhalation pattern of the formulation. Based on these findings, we propose the ETB-SLN DPI as a promising treatment modality for the NSCLC patients. 相似文献
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Zahra Shabeh tu Syed Waqar A.A. Rafiq Nouman Shah Wiqar H. Iqbal Zafar 《Protection of Metals and Physical Chemistry of Surfaces》2021,57(2):321-328
Protection of Metals and Physical Chemistry of Surfaces - Chromium oxide thin films were grown on Al2O3 substrates by ablating a pure Cr2O3 target using a KrF excimer laser. The energy density on... 相似文献
46.
Using Fuzzy Cost‐Based FMEA,GRA and Profitability Theory for Minimizing Failures at a Healthcare Diagnosis Service 下载免费PDF全文
Samira Abbasgholizadeh Rahimi Afshin Jamshidi Daoud Ait‐Kadi Angel Ruiz 《Quality and Reliability Engineering International》2015,31(4):601-615
This paper proposes an integrated approach to identify, evaluate and improve the potential failures in a service setting. This integrated approach combines Fuzzy cost‐based service‐specific FMEA (FCS‐FMEA), Grey Relational Analysis (GRA) and profitability theory for better prioritization of the service failures by considering cost as an important issue and using the profitability theory in a way that the corrective actions costs are taken into account. Considering profitability with FCS‐FMEA and GRA reduces the losses caused by failure occurrence. Besides, a maximization linear mathematical problem is used to select the best mix of failures to be repaired. We apply our approach to an academic example concerning the potential failures diagnosis of the Internal Medicine service of a hospital located in Seoul, Korea. We applied our approach and solved the associated maximization problem by a commercial solver, producing an optimal solution which indicates the most convenient mix of failures to be repaired by considering available budget. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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A simple and fast method based on solid phase extraction (SPE) applying zinc oxide (ZnO) nanoparticles and atomic absorption spectrometry (AAS) was developed for the trace amount determination of silver (Ag) in aqueous samples. The method linearity was in the range of 14 to 700 ng mL?1. The extraction efficiency of Ag was greater than 98% and limit of detection (LOD) was 4.2 ng mL?1. The preconcentration factor was 200 and the relative standard deviation (RSD%) of the method was 3.7% (n = 6). 相似文献
49.
In this work a newly semi polar extraction phase of carboxylated multiwalled carbon nanotube (MWCNTs) reinforced sol-gel immobilized polypropylene hollow fiber was prepared by low temperature hydrothermal process. It is coupled with flame atomic absorption spectroscopy was employed in the extraction and determination of cobalt and cadmium ions in wastewaters. The main factors influencing the pre-concentration and extraction of the metal ions have been examined in detail. Detection limits obtained in this way for Co(II) and Cd(II) ions were 0.0186 and 0.024 ng mL?1, respectively. 相似文献
50.
A magnetic solid phase extraction was developed for preconcentration of Cu(II) as a 4-bromo-2-(2,4-dichloro-phenylimino)-phenol complex on Fe3O4/SiO2 nanoparticles prior to its determination by atomic absorption spectroscopy. The effect of different parameters influencing the formation of the Cu complex and the extraction efficiency of the Cu complex were studied. Under optimal conditions, the calibration graph showed linearity in the range of 0.946–700 µg L?1 (R2 = 0.9995) of Cu(II). The limit of detection and relative standard deviation of the method (n = 6) were 0.283 µg L?1 and 3.0%, respectively. The method was successfully applied to determine copper (II) in water samples. 相似文献