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排序方式: 共有2720条查询结果,搜索用时 15 毫秒
1.
Babak Jaleh Mahmoud Nasrollahzadeh Bahareh Feizi Mohazzab Mahtab Eslamipanah Mohaddeseh Sajjadi Hossein Ghafuri 《Ceramics International》2021,47(8):10389-10425
In both developing and industrialized/developed countries, various hazardous/toxic environmental pollutants are entering water bodies from organic and inorganic compounds (heavy metals and specifically dyes). The global population is growing whereas the accessibility of clean, potable and safe drinking water is decreasing, leading to world deterioration in human health and limitation of agricultural and/or economic development. Treatment of water/wastewater (mainly industrial water) via catalytic reduction/degradation of environmental pollutants is extremely critical and is a major concern/issue for public health. Light and/or laser ablation induced photocatalytic processes have attracted much attention during recent years for water treatment due to their good (photo)catalytic efficiencies in the reduction/degradation of organic/inorganic pollutants. Pulsed laser ablation (PLA) is a rather novel catalyst fabrication approach for the generation of nanostructures with special morphologies (nanoparticles (NPs), nanocrystals, nanocomposites, nanowires, etc.) and different compositions (metals, alloys, oxides, core-shell, etc.). Laser ablation in liquid (LAL) is generally considered a quickly growing approach for the synthesis and modification of nanomaterials for practical applications in diverse fields. LAL-synthesized nanomaterials have been identified as attractive nanocatalysts or valuable photocatalysts in (photo)catalytic reduction/degradation reactions. In this review, the laser ablation/irradiation strategies based on LAL are systematically described and the applications of LAL synthesized metal/metal oxide nanocatalysts with highly controlled nanostructures in the degradation/reduction of organic/inorganic water pollutants are highlighted along with their degradation/reduction mechanisms. 相似文献
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3.
Oblivious polynomial evaluation (OPE) is a two-party protocol that allows a receiver, R to learn an evaluation f(α), of a sender, S's polynomial f(x), whilst keeping both α and f(x) private. This protocol has attracted a lot of attention recently, as it has wide ranging applications in the field of cryptography.
In this article we review some of these applications and, additionally, take an in-depth look at the special case of information theoretic OPE. Specifically, we provide a current and critical review of the existing information theoretic OPE protocols in the literature. We divide these protocols into two distinct cases (three-party and distributed OPE) allowing for the easy distinction and classification of future information theoretic OPE protocols. In addition to this work, we also develop several modifications and extensions to existing schemes, resulting in increased security, flexibility and efficiency. Lastly, we also identify a security flaw in a previously published OPE scheme. 相似文献
4.
Zeraati Malihe Alizadeh Vali Kazemzadeh Parya Safinejad Moosareza Kazemian Hossein Sargazi Ghasem 《Journal of Porous Materials》2022,29(1):257-267
Journal of Porous Materials - A Ni-MOF-based novel electrochemical sensor was synthesized with high surface area of 1381 m2/g, significant porosity of 1.14–9.6 nm and average... 相似文献
5.
Mahmoodi Javad Nezamabadi-pour Hossein Abbasi-Moghadam Dariush 《Multimedia Tools and Applications》2022,81(15):20945-20961
Multimedia Tools and Applications - With the rapid development of detecting violent behaviors in surveillance cameras, requests on systems that automatically recognize violent events are expanded.... 相似文献
6.
Alireza Ramezani Hossein Abdizadeh Mohammad Reza Golobostanfard 《Ceramics International》2021,47(13):17895-17906
In this work, the BaTiO3 and SrTiO3 thin films as well as BaTiO3/SrTiO3 lamellar composites are synthesized via sol-gel spin-coating method. The formation of corresponding phases from their sols is investigated by virtue of X-ray diffraction on their powders, which confirms the formation of tetragonal structure for BaTiO3, but cubic structure for SrTiO3. The field emission scanning electron microscopy images show that crack-free films with different morphologies are formed in each sample. Likewise, by changing periodicity of the samples, the morphology of the composite samples is changed. As the number of layers increases from 1 to 20, the band gap reduces from 4.38 eV to 4.10 eV for BaTiO3 samples and from 4.13 eV to 3.80 eV for SrTiO3 samples confirmed by UV–Vis spectra. The band gap of periodicity = 1 sample is higher than that of BaTiO3, while band gaps of periodicity = 2 and 5 composites mount between those of BaTiO3 and SrTiO3. In addition, the refractive indices of multi-stacked composites are about 0.2 lesser than refractive indices of BaTiO3 sample in high wavelengths. The periodicity dependence of optical frequency dielectric constant, dielectric loss, impedance, Urbach tail, extinction coefficient, and electric modulus of multi-stacked composites are also studied. 相似文献
7.
In the presence of modified methylaluminoxane as cocatalyst, the behavior of a binary catalytic system based on pyridine-imine nickel ( N ) and iron ( F ) catalysts was evaluated in order to reach a proper mixture of polyethylene (PE). A computational study along with kinetic profile suggested that the catalyst F with higher electron affinity (A) and electrophilicity (ω) in the methyl cationic active center and stronger interaction with the monomer led to high integrated monomer consumption and higher activity. In addition, the samples produced by the mixture of catalysts showed a higher value of [19.4 × 104 g (PE) mol (Fe+Ni)−1 h−1)], melting point (127.8 °C), and crystallinity extent (41.29%) than the samples produced by the single catalysts. The addition of multiwalled carbon nanotubes (MWCNT) into the polymerization media reduced the activity of catalysts [from 7.50 × 104 to 0.66 × 104 g (PE) mol (Fe+Ni)−1 h−1] and the thermal properties of the low-density polyethylene nanocomposite samples. However, the sample containing 2.33% MWCNT20-30 improved the total thermal stability of the neat polyethylene blend up to 400 °C. Scanning electron microscope images of the samples demonstrated irregular to virtually uniform morphologies were obtained through the in situ and solution-mixing techniques. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47376. 相似文献
8.
Al-Musawi Tariq J. Mahvi Amir Hossein Khatibi Aram Dokht Balarak Davoud 《Journal of Porous Materials》2021,28(3):835-852
Journal of Porous Materials - In the present work, the adsorption performance of powdered activated carbon magnetized by iron(III) oxide magnetic nanoparticles (PAC@Fe3O4-MN) for the removal of... 相似文献
9.
Hossein Arayesh Nadereh Golshan Ebrahimi Behnam Khaledi Masood Khabazian Esfahani 《应用聚合物科学杂志》2020,137(41):49243
Chain extension/branching by reactive processing is a well-known method to enhance the rheological properties of polymers. In this study, pyromellitic dianhydride, poly(glycolic acid), triglycidyl isocyanurate, and bisphenol A diglycidyl ether were used as chain extender/branching agents to produce branched Polyethylene terephthalate (PETs) with four different molecular structures. According to the linear rheological characterizations, the storage modulus and complex viscosity of modified PET samples enhanced significantly after branching. The shear viscosities of modified PET show a pronounced shear-thinning behavior and a remarkable increase at low frequencies, which can be an indication of the existence of long-chain branches (LCBs) in the molecular structure of polymer and broadening the molecular weight distribution. Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC) analysis were used to investigate the effect of branching agents on the chemical structure and thermal properties of PET, respectively. DSC results show that higher amounts of LCBs lead to lower melting and crystallization temperatures. 相似文献
10.
Vahabzadeh Nosrat-Ali Boochani Arash Elahi Seyed Mohammad Akbari Hossein 《SILICON》2020,12(9):2165-2178
Silicon - Thermodynamic stability, electronic and optical properties of the Zr2TiSi compound in the bulk and its [111] films have been investigated, based on the density functional theory (DFT)... 相似文献