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排序方式: 共有198条查询结果,搜索用时 15 毫秒
1.
Cssio Luiz Coutinho Almeida-da-Silva Nallusamy Sivakumar Homer Asadi Anna Chang-Chien M. Walid Qoronfleh David M. Ojcius Musthafa Mohamed Essa 《Molecules (Basel, Switzerland)》2022,27(13)
Boswellia trees, found throughout the Middle East and parts of Africa and Asia, are the source of frankincense oil. Since antiquity, frankincense has been traded as a precious commodity, but it has also been used for the treatment of chronic disease, inflammation, oral health, and microbial infection. More recently, the bioactive components of Boswellia trees have been identified and characterized for their effects on cancer, microbial infection (especially infection by oral pathogens), and inflammation. Most studies have focused on cell lines, but more recent research has also investigated effects in animal models of disease. As natural products are considered to be safer than synthetic drugs, there is growing interest in further developing the use of substances such as frankincense oil for therapeutic treatment. 相似文献
2.
Youssef Walid Mohamed El Sheikh Ahmed Said Ahmed Sherien Hussien Morsy Ahmed Morsy Ahmed 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):87-96
Journal of Radioanalytical and Nuclear Chemistry - Polyacrylic acid/polyaniline composite (a three-dimensional cross-linked hydrophilic chelating polymeric sorbent) was improved for promoted... 相似文献
3.
Subuhi Khan Mustafa Walid Al-Saad Ghazala Yasmin 《Applied mathematics and computation》2010,217(5):2169-2183
In this paper, the concepts and the formalism associated with monomiality principle and Sheffer sequences are used to introduce family of Hermite-based Sheffer polynomials. Some properties of Hermite-Sheffer polynomials are considered. Further, an operational formalism providing a correspondence between Sheffer and Hermite-Sheffer polynomials is developed. Furthermore, this correspondence is used to derive several new identities and results for members of Hermite-Sheffer family. 相似文献
4.
This paper discusses Supply Chain Network (SCN) design problem under uncertainty, and presents a critical review of the optimization models proposed in the literature. Some drawbacks and missing aspects in the literature are pointed out, thus motivating the development of a comprehensive SCN design methodology. Through an analysis of supply chains uncertainty sources and risk exposures, the paper reviews key random environmental factors and discusses the nature of major disruptive events threatening SCN. It also discusses relevant strategic SCN design evaluation criteria, and it reviews their use in existing models. We argue for the assessment of SCN robustness as a necessary condition to ensure sustainable value creation. Several definitions of robustness, responsiveness and resilience are reviewed, and the importance of these concepts for SCN design is discussed. This paper contributes to framing the foundations for a robust SCN design methodology. 相似文献
5.
The interaction of Ru3(CO)12 with a novel family of monodentate V‐shaped Schiff base ligands (L1–4; L1: (E)‐1‐(4‐((4‐bromobenzylidene)amino)phenyl)ethanone, L2: (E)‐1‐(3‐(4‐(dimethylamino)benzylideneamino)phenyl)ethanone, L3: (E)‐1‐(4‐(4‐(dimethylamino)benzylideneamino)phenyl)ethanone, L4: (E)‐1‐(3‐(3,4‐dimethoxybenzylideneamino)phenyl)ethanone) in air under atmospheric pressure afforded the novel complexes [Ru(CO)3(L1–4)2]. The parent ligands and their complexes were characterized using elemental analyses and spectroscopic techniques. In addition, the structure of the representative ligand L1 was determined using single‐crystal X‐ray analysis. The stereochemistry and theoretical optimization of the three‐dimensional geometry of the ligands and their complexes were justified. In vitro antimicrobial screening against bacterial stains Escherichia coli and Staphylococcus aureus and fungus Candida albicans was conducted. Cytotoxicity of the compounds as anti‐tumour agents was evaluated against liver carcinoma (HepG2), breast carcinoma (MCF7) and colon carcinoma (HCT‐116) cell lines relative to cisplatin and doxorubicin. The complexes showed variable in vitro cytotoxic activities against the three studied cell lines, with IC50 values less than those of cis‐platin, and thus appear to be building blocks for promising anti‐tumour agents. 相似文献
6.
Saraya Roshdy E. Hassan Yasser F. Eltukhi Walid E. Salman Baher I. 《Journal of fluorescence》2022,32(5):1725-1732
Journal of Fluorescence - Vonoprazan (VON) has been approved recently via US-FDA in 2015 as the first in class of potassium competitive acid blocker group. VON is used for management of... 相似文献
7.
Walid Mabrouk Ridha Lafi Jean Franois Fauvarque Amor Hafiane Cyrille Sollogoub 《先进技术聚合物》2021,32(1):304-314
The purpose of this work is to study the desalination of brackish water using a new ion exchange membrane, made from sulfochlorated polyethersulfone (Cl‐PES), and crosslinked using aminated polyethersulfone (NH2‐PES) as a crosslinking reagent. This membrane, named ClNH2 membrane, has been obtained by reaction between Cl‐PES with 1.3 SO2Cl groups per monomer unit and 0.2 equivalent amount of NH2‐PES. ClNH2 membrane has been characterized in terms of contact angle, transport number, intrinsic conductivity, and water uptake (as a function of temperature). Electrodialysis performances of the newly synthetized membranes have been measured using an electrodialysis cell at a laboratory scale and compared to commercial membranes. All the experiments have been performed using synthetic brackish water solutions prepared from sodium chloride salts with different concentrations (varying from 0.5 to 5.0 g/L). The concentration of different water samples obtained has been found to be below the amount recommended by the World Health Organization (WHO) for drinking water. 相似文献
8.
9.
Thermal degradation studies of alkyl-imidazolium salts and their application in nanocomposites 总被引:1,自引:0,他引:1
Walid H Awad Jeffrey W Gilman Marc Nyden Thomas E Sutto Paul C Trulove Douglas M Fox 《Thermochimica Acta》2004,409(1):3-11
Increasing the thermal stability of organically-modified layered silicates is one of the key points in the successful technical application of polymer-layered silicate nanocomposites on the industrial scale. To circumvent the detrimental effect of the lower thermal stability of alkyl ammonium-treated montmorillonite, a series of alkyl-imidazolium molten salts were prepared and characterized by elemental analysis, thermogravimetry (TGA) and thermal desorption mass spectroscopy (TDMS). The effect of counter ion, alkyl chain length and structural isomerism on the thermal stability of the imidazolium salts was investigated. Alkyl-imidazolium-treated montmorillonite clays were prepared by ion exchange of the imidazolium salts with Na-montmorillonite. These organically-modified clays were characterized by X-ray diffraction (XRD), TDMS and thermogravimetry coupled with Fourier transform infrared spectroscopy (TGA-FTIR), and compared to the conventional quaternary alkyl ammonium montmorillonite. Results indicate that the counter ion has an effect on the thermal stability of the imidazolium salts, and that imidazolium salts with PF6−, N(SO2CF3)2− and BF4− anions are thermally more stable than the halide salts. A relationship was observed between the chain length of the alkyl group and the thermo-oxidative stability; as the chain length increased from propyl, butyl, decyl, hexadecyl, octadecyl to eicosyl, the stability decreased. The results also show that the imidazolium-treated montmorillonite has greater thermal stability compared to the imidazolium halide. Analysis of the decomposition products by FTIR provides an insight about the decomposition products which are water, carbon dioxide and hydrocarbons. 相似文献
10.
We study the adiabatic time evolution of quantum resonances over time scales which are small compared to the lifetime of the
resonances. We consider three typical examples of resonances: The first one is that of shape resonances corresponding, for
example, to the state of a quantum-mechanical particle in a potential well whose shape changes over time scales small compared
to the escape time of the particle from the well. Our approach to studying the adiabatic evolution of shape resonances is
based on a precise form of the time-energy uncertainty relation and the usual adiabatic theorem in quantum mechanics. The
second example concerns resonances that appear as isolated complex eigenvalues of spectrally deformed Hamiltonians, such as
those encountered in the N-body Stark effect. Our approach to study such resonances is based on the Balslev-Combes theory
of dilatation-analytic Hamiltonians and an adiabatic theorem for nonnormal generators of time evolution. Our third example
concerns resonances arising from eigenvalues embedded in the continuous spectrum when a perturbation is turned on, such as
those encountered when a small system is coupled to an infinitely extended, dispersive medium. Our approach to this class
of examples is based on an extension of adiabatic theorems without a spectral gap condition. We finally comment on resonance
crossings, which can be studied using the last approach. 相似文献