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排序方式: 共有2371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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Fatemeh Norouzi Jobie Mojtaba Ranjbar Akbar Hajizadeh Moghaddam Mahmoud Kiani 《Advanced Powder Technology》2021,32(6):2043-2052
For the first time in this study, Zinc oxide nanoparticles were biosynthesized by the eco-friendly and cost-effective procedure using Amygdalus scoparia stem bark extract then used as antibacterial, antifungal, anticancer, and anti-diabetic agents. The characterization techniques confirmed the biosynthesis, crystalline nature, structure, size, elemental composition of ZnO NPs and bioactive compounds that exist in A. scoparia extract accounting for Zn2+ ion reduction, capping and stabilization of ZnO NPs. The ZnO NPs displayed remarkable inhibitory activity against E. coli, E. aerigenes, S. aureus, P. oryzae, F. thapsinum, and F. semitectum compared to antibiotic standards. The ZnO NPs showed significant inhibitory effects on cancer cell lines, while it had no toxic effect on Vero normal cell line. The ZnO NPs (30 mg/kg)-treated diabetic rats showed significantly higher levels of insulin and lower AST, ALT and blood glucose compared with the STZ induced diabetic group and other treated groups (P < 0.05). The ZnO NPs- and extract-treated rats showed significantly higher levels of IR, GluT2, and GCK expression and lower TNFα expression compared with the STZ induced diabetic rats. Our findings showed that ZnO NPs represented an outstanding performance for biological applications. 相似文献
4.
Basaleh A. S. Amin M. S. Mahmoud M. H. H. 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(9):3829-3841
Journal of Inorganic and Organometallic Polymers and Materials - The present work offers beneficial method for Hg (II) elimination from aqueous solution. ZnIn2S4/g-C3N4 nanocomposites were... 相似文献
5.
Mahmoud MOUSTAFA Saad ALAMRI Hoida ZAKI Naglaa LOUTFY Tarek TAHA Ali SHATI Mohamed ALKAHTANI Sajda SIDDIQI 《Biocell》2019,43(2):81-88
The present research reports of quick and marked changes induced by plant extract of Euryops arabicus in the
gene expression of 49-kDa apyrases, cytoskeletal proteins, ATPases, ADPase and amount of amino acid of pea (Pisum
sativum L. var. Alaska). Pellets of cytoskeletals proteins (27000 xg) were probed with anti-apyrase antibody, biotinylated
anti-rat, actin and alpha and beta-tubulin for Western blotting. ATPase and ADPase activities were determined based
on the hydrolytic efficacy of adenine triphosphate and adenine diphosphate. By 72 hours, the abundance of apyrases,
cytoskeletal proteins and amount of amino acid in pellets of 27000 xg of germinated pea seeds in E. arabicus extracts
were sharply increased than those sown in distilled water. All the samples exhibited that the stems had more amount
from apyrases, cytoskeletal proteins, amino acids and ATPase and ADPase activities than primary leaves and primary
roots that were germinated either on E. arabicus water extract or in distilled water. Based on the enzyme’s capability to
hydrolyse nucleotide triphosphate and nucleotide diphosphate as well as the direct association between expression of
49-kDa apyrase and cytoskeletal proteins, E. arabicus water extract had an important effect on plant germinations. 相似文献
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Mahmoud Ghazavi Ahad Ehsani Yamchi Javad Nazari Afshar 《Geotextiles and Geomembranes》2018,46(3):312-318
In very soft soils, the bearing capacity of stone columns may not improve significantly due to very low confinement of the surrounding soil. Therefore, they may be reinforced with geosynthetics by using vertical encasement or horizontal layers. Very limited studies exist on horizontally reinforced stone columns (HRSCs). In this research, some large body laboratory tests have been performed on horizontally reinforced stone columns with diameters of 60, 80, and 100?mm and groups of stone columns with 60?mm diameter. Results show that the bearing capacity of stone columns increases by using horizontally reinforcing layers. Also, they reduce lateral bulging of stone columns by their frictional and interlocking effects with stone column aggregates. Finally, numerical analyses were carried out to study main affecting parameters on the bearing capacity of HRSCs. Numerical analysis results show that the bearing capacity increases considerably with increasing the number of horizontal layers and decreasing space between layers. 相似文献
8.
In this article, a new generalization of the inverse Lindley distribution is
introduced based on Marshall-Olkin family of distributions. We call the new distribution,
the generalized Marshall-Olkin inverse Lindley distribution which offers more flexibility
for modeling lifetime data. The new distribution includes the inverse Lindley and the
Marshall-Olkin inverse Lindley as special distributions. Essential properties of the
generalized Marshall-Olkin inverse Lindley distribution are discussed and investigated
including, quantile function, ordinary moments, incomplete moments, moments of
residual and stochastic ordering. Maximum likelihood method of estimation is considered
under complete, Type-I censoring and Type-II censoring. Maximum likelihood estimators
as well as approximate confidence intervals of the population parameters are discussed.
A comprehensive simulation study is done to assess the performance of estimates based
on their biases and mean square errors. The notability of the generalized Marshall-Olkin
inverse Lindley model is clarified by means of two real data sets. The results showed the
fact that the generalized Marshall-Olkin inverse Lindley model can produce better fits
than power Lindley, extended Lindley, alpha power transmuted Lindley, alpha power
extended exponential and Lindley distributions. 相似文献
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