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111.
Structural Chemistry - DFT/B3LYP calculations with full geometry optimizations have been carried out on 1-phenylazo-2-naphthol and their metal complexes of formula M(MePhNap)2 (M?=?Ni,... 相似文献
112.
113.
Dimensional reduction is carried out for space-times, with or without torsion, which possess non-abelian isometries. The spectra and the equations of motion of the dimensionally reduced theory are obtained directly from the higher dimensional theory. The spectra of the reduced theories are naturally given in terms of scalar fields and antisymmetric tensor field strengths. A method of studying the dependence on the extra dimensions is suggested. 相似文献
114.
We present all solutions to the equation with at most eight primes, improve the bound on the nonsolvability of the Erdös-Moser equation , and discuss the computational search techniques used to generate examples of perfectly weighted graphs.
115.
One of the most important information given by data envelopment analysis models is the cost, revenue and profit efficiency of decision making units (DMUs). Cost efficiency is defined as the ratio of minimum costs to current costs, while revenue efficiency is defined as the ratio of maximum revenue to current revenue of the DMU. This paper presents a framework where data envelopment analysis (DEA) is used to measure cost, revenue and profit efficiency with fuzzy data. In such cases, the classical models cannot be used, because input and output data appear in the form of ranges. When the data are fuzzy, the cost, revenue and profit efficiency measures calculated from the data should be uncertain as well. Fuzzy DEA models emerge as another class of DEA models to account for imprecise inputs and outputs for DMUs. Although several approaches for solving fuzzy DEA models have been developed, numerous deficiencies including the -cut approaches and types of fuzzy numbers must still be improved. This scheme embraces evaluation method based on vector for proposed fuzzy model. This paper proposes generalized cost, revenue and profit efficiency models in fuzzy data envelopment analysis. The practical application of these models is illustrated by a numerical example. 相似文献
116.
Fadoua Asraoui Ayoub Kounnoun Francesco Cacciola Fouad El Mansouri Imad Kabach Yassine Oulad El Majdoub Filippo Alibrando Katia Arena Emanuela Trovato Luigi Mondello Adnane Louajri 《Molecules (Basel, Switzerland)》2021,26(11)
Medicinal plants offer imperative sources of innovative chemical substances with important potential therapeutic effects. Among them, the members of the genus Inula have been widely used in traditional medicine for the treatment of several diseases. The present study investigated the antioxidant (DPPH, ABTS and FRAP assays) and the in vitro anti-hyperglycemic potential of aerial parts of Inula viscosa (L.) Aiton (I. viscosa) extracts through the inhibition of digestive enzymes (α-amylase and α-glucosidase), responsible of the digestion of poly and oligosaccharides. The polyphenolic profile of the Inula viscosa (L.) Aiton EtOAc extract was also investigated using HPLC-DAD/ESI-MS analysis, whereas the volatile composition was elucidated by GC-MS. The chemical analysis resulted in the detection of twenty-one polyphenolic compounds, whereas the volatile profile highlighted the occurrence of forty-eight different compounds. Inula viscosa (L.) Aiton presented values as high as 87.2 ± 0.50 mg GAE/g and 78.6 ± 0.55mg CE/g, for gallic acid and catechin, respectively. The EtOAc extract exhibited the higher antioxidant activity compared to methanol and chloroform extracts in different tests with (IC50 = 0.6 ± 0.03 µg/mL; IC50 = 8.6 ± 0.08 µg/mL; 634.8 mg ± 1.45 AAE/g extract) in DPPH, ABTS and FRAP tests. Moreover, Inula viscosa (L.) Aiton leaves did show an important inhibitory effect against α-amylase and α-glucosidase. On the basis of the results achieved, such a species represents a promising traditional medicine, thanks to its remarkable content of functional bioactive compounds, thus opening new prospects for research and innovative phytopharmaceuticals developments. 相似文献
117.
Fareghi-Alamdari Reza Zekri Negar Mansouri Fariborz 《Research on Chemical Intermediates》2017,43(11):6537-6551
Research on Chemical Intermediates - Cu0.5Co0.5Fe2O4 magnetic nanoparticles were prepared, characterized and employed as bench-top, highly active and magnetically separable nanocatalysts for the... 相似文献
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119.
Oscar P. Yanchatua Aguayo Lynda Mouheb Katherine Villota Revelo Paola A. Vsquez-Ucho Prasad P. Pawar Ashiqur Rahman Clayton Jeffryes Thibault Terencio Si Amar Dahoumane 《Molecules (Basel, Switzerland)》2022,27(2)
Bio-nanotechnology has emerged as an efficient and competitive methodology for the production of added-value nanomaterials (NMs). This review article gathers knowledge gleaned from the literature regarding the biosynthesis of sulfur-based chalcogenide nanoparticles (S-NPs), such as CdS, ZnS and PbS NPs, using various biological resources, namely bacteria, fungi including yeast, algae, plant extracts, single biomolecules, and viruses. In addition, this work sheds light onto the hypothetical mechanistic aspects, and discusses the impact of varying the experimental parameters, such as the employed bio-entity, time, pH, and biomass concentration, on the obtained S-NPs and, consequently, on their properties. Furthermore, various bio-applications of these NMs are described. Finally, key elements regarding the whole process are summed up and some hints are provided to overcome encountered bottlenecks towards the improved and scalable production of biogenic S-NPs. 相似文献
120.
Azadeh Mansouri Ahmad Mahmoudi Aznaveh Farah Torkamani-Azar J. Afshar Jahanshahi 《Optical Review》2009,16(2):49-53
In objective image quality metrics, one of the most important factors is the correlation of their results with the perceived
quality measurements. In this paper, a new method is presented based on comparing between the structural properties of the
two compared images. Based on the mathematical concept of the singular value decomposition (SVD) theorem, each matrix can
be factorized to the products of three matrices, one of them related to the luminance value while the two others show the
structural content information of the image. A new method to quantify the quality of images is proposed based on the projected
coefficients and the left singular vector matrix of the disturbed image based on the right singular vector matrix of the original
image. To evaluate this performance, many tests have been done using a widespread subjective study involving 779 images of
the Live Image Quality Assessment Database, Release 2005. The objective results show a high rate of correlation with subjective
quality measurements. 相似文献