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排序方式: 共有359条查询结果,搜索用时 93 毫秒
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Mandana Amiri Zahra Tofighi Ali Khodayari Abolfazl Bezaatpour Shabnam Sohrabnezhad Vladyslav Mishyn Rabah Boukherroub Sabine Szunerits 《应用有机金属化学》2020,34(10):e5871
We report a Cu-based metal–organic framework (MOF) decorated by CuO nanostructures as an efficient catalyst for the oxygen evolution reaction (OER). MIL-53(Cu) was synthesized by a hydrothermal approach using 1,4-bezenedicarboxylic acid as organic precursor and further annealed at 300°C to form CuO nanostructures on its surface. The produced electrocatalyst, CuO@MIL-53(Cu), was characterized using various techniques. Under alkaline conditions, the developed electrocatalyst exhibited an overpotential of 801 and 336 mV versus RHE at 10 and 1 mA cm−2, respectively. The reproducibility of the catalytic performance was validated using several electrodes. It was confirmed that the CuO hair-like nanostructures grown on MIL-53(Cu) using thermal treatment exhibit high OER activity, good kinetics and durability. CuO@MIL-53(Cu) is an economic noble-metal-free OER electrocatalyst. It has potential for application as anode material for sustainable energy technologies like batteries, fuel cells and water electrolysis. 相似文献
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Saba Hemmati Mohammad Yousefi Mirmehdi Hashemi Salehi Mahdis Amiri Malak Hekmati 《应用有机金属化学》2020,34(8):e5653
This paper develops a green method for in situ decorated of palladium nanoparticles over Fe3O4 nanoparticles, by utilizing Strawberry fruit extract and ultrasound irradiations, with no use of any toxic reducing agent. The structure's characterization is represented via diverse analytical methods such as FT-IR, FE-SEM, TEM, WDX, ICP, EDS and XXPS. Catalytic efficiency of magnetic Fe3O4@Strawberry/Pd nanocatalyst is investigated in production of different biphenyls with good turnover frequencies (TOF) and turnover numbers (TON) through Suzuki coupling reactions. Furthermore, the catalyst could be recovered and reused 7 runs without considerable palladium leaching or alteration in its performance. 相似文献
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Hosseini Seyed Ghorban Gholami Setareh Mahyari Mojtaba 《Research on Chemical Intermediates》2019,45(3):1527-1543
Research on Chemical Intermediates - Nickel cobalt bimetallic nanoparticles (NiCo NPs) with different molar ratios were stabilized over three-dimensional nitrogen-doped graphene [3D-(N)G] by a... 相似文献
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Taghavizadeh Yazdi Mohammad Ehsan Modarres Masoomeh Amiri Mohammad Sadegh Darroudi Majid 《Research on Chemical Intermediates》2019,45(3):1105-1116
Research on Chemical Intermediates - We have synthesized silver nanoparticles (Ag-NPs) via a simple and eco-friendly method through the utilization of aqueous aerial parts of Salvia leriifolia... 相似文献
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Seyed Ahmad Razavizadeh Setareh Sheikh 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2019,93(4):625-630
Russian Journal of Physical Chemistry A - A new simple and accurate functional form for an attractive parameter α is introduced for Peng–Robinson equation of state. The modified... 相似文献
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Synthesis of a graphene‐based nanocomposite for the dispersive solid‐phase extraction of vancomycin from biological samples 下载免费PDF全文
Faezeh Khalilian Somayeh Amiri Hanzaki Mohammad Yousefi 《Journal of separation science》2015,38(6):975-981
The approach of this work was to study the capability of graphene‐based materials in the field of biological sample preparation. A polypyrrole/graphene composite was synthesized and characterized. The potential of the nanocomposite was investigated as a sorbent in dispersive solid‐phase extraction followed by high‐performance liquid chromatography with UV detection for vancomycin as a model drug. The effect of different parameters influencing extraction efficiency such as sample pH and sample volume, ionic strength, extraction time, type, and volume of desorption solvent and desorption time were investigated. A comparison study was also conducted between polypyrrole/graphene and some different novel and classic sorbents. Under optimized conditions, the calibration curve for vancomycin showed linearity in the range of 0.05–10 μg/mL. In addition, limits of detection, and quantification were 0.003 and 0.01 μg/mL, respectively. The intraday and interday relative standard deviations at a concentration of 0.05 μg/mL (n = 3) were 1.6 and 2.1%, respectively. Furthermore, the proposed method was successfully applied for the determination of vancomycin in plasma and urine samples. The relative recoveries indicated the feasibility of graphene‐based sorbents in biological sample analysis. 相似文献
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Naader Alizadeh Mahsa Amiri Fariba Mohammadpour Parviz Norouzi 《Electroanalysis》2023,35(10):e202300114
This research represents a novel detection method of acetone level in the exhaled breath samples (RH=88 %) based on polypyrrole/tungsten oxide (PPy/WO3) nanocomposite sensor. The PPy/WO3 sensor was fabricated by the deposition of nanocomposite on/between interdigitated electrodes (IDEs) through electrospray coating and was then characterized by FE-SEM imaging. In this detection method, the coulometric signal of the sensor was calculated using Fast Fourier Continuous Cyclic Voltammetry (FFTCCV), where cyclic voltammetry (CV) was applied to the sensor in the defined potential rang and then charge changes of the sensor was obtained by integration of the current in all scanned potential ranges. FFTCCV method enhances the sensitivity of the sensor when exposed to the gas mixtures containing acetone. In addition to its fast coulometric response time (≤5 s) in the two linear ranges of 0.7–2.8 ppm and 2.8–28.2 ppm (R2=0.99), FFTCCV method provides the low detection limit of 70 ppb, and high sensitivity toward acetone at the optimum values of the parameters. The fabricated sensor showed great selectivity toward acetone when exposed to humid air and some exhaled gas like carbon dioxide, ammonia, methanol, ethanol and alkyl amines. The results were very satisfying as the sensor was capable to detect different acetone levels in human exhaled breath as non-invasive diagnosis of diabetes with a good correlation (R2≃0.9) to the routine blood sugar test taken by different commercial glucometers results. 相似文献