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101.
On the fractional differential equations with uncertainty   总被引:1,自引:0,他引:1  
This paper is based on the concept of fuzzy differential equations of fractional order introduced by Agarwal et al. [R.P. Agarwal, V. Lakshmikantham, J.J. Nieto, On the concept of solution for fractional differential equations with uncertainty, Nonlinear Anal. 72 (2010) 2859-2862]. Using this concept, we prove some results on the existence and uniqueness of solutions of fuzzy fractional differential equations.  相似文献   
102.
No equipment (system) can be perfectly reliable in spite of the utmost care and best efforts on the part of the designer, decision-maker and manufacturer. The two sides of maintenance are corrective and preventive maintenance. It is generally assumed that a preventive maintenance action is less costly than a repair maintenance action. We examine this proposition in detail on the basis of a failure-time model that relates conformance quality to reliability. Illustratively, we present reliability in the context of contracts with asymmetric information. The model shows how to overcome information rents through price distortions and quantity rationing. The paper ends with a conclusion and an outlook to future studies.  相似文献   
103.
This study delves into a comprehensive physical analysis of entropy measures applied to sodium oxide Na 2 O . A key idea in information theory and thermodynamics, entropy is essential to comprehending the stability of a system. The study clarifies the intricate relationships and physical properties of Na 2 O by combining theoretical analysis with statistical methods, providing important knowledge for material design and industrial operations. In a chemical graph, atoms are shown by vertices while their bonding are illustrated by edges. Sodium oxide is a major contributor to manufacture glass, it also has potential applications in CO 2 sequestration, transparent materials, biomedical devices and nano grating glass. A topological index is a relationship between the molecular graph and its topology. We have computed various graph entropies based on different topological indices of chemical graph of sodium oxide. Further we have integrated these graph entropies with distinct thermodynamical measures of sodium oxide by developing mathematical models between both quantities. We have developed these mathematical frameworks in MATLAB. All the models are selected relying on the least mean squared error or sum of squared error.  相似文献   
104.
The microbial transformation of (+)-adrenosterone (1) by Cephalosporium aphidicola afforded three metabolites identified as androsta-1,4-diene-3,11,17-trione (2), 17beta-hydroxyandrost-4-ene-3,11-dione (3) and 17beta-hydroxyandrosta-1,4-diene-3,11-dione (4). The fermentation of 1 with Fusarium lini also produced metabolites 2 and 4, while the fermentation with Trichothecium roseum afforded metabolite 3. The structures of transformed products were determined by spectroscopic methods.  相似文献   
105.
Phytochemicals investigation of the whole plant of Zygophyllum atriplicoides resulted in the isolation of two new triterpenoidal saponins together with a known compound. The structure of the new compounds atriplicosaponin A (1) and atriplicosaponin B (2) were established as 3-O-[alpha-D-glucopyranosyl-(1-->2)-beta-D-xylopyranosyl]-hederagenin and 27 alpha-hydroxyurs-12-ene-3-O-[beta-D-glucopyranosyl(1-->4)(2-O-sulpho)-beta-D-quinovopyranoside] and known compound was identified as 3-O-[beta-D-glucopyranosyl]-beta-sitosterol. The structure elucidations of the compounds were based primarily on 1D and 2D-NMR analysis, including COSY, HMBC and HMQC correlations.  相似文献   
106.
Laser irradiation effects on morphological, structural and mechanical properties of copper are explored. The targets are exposed by employing low-cost continuous wave (CW) laser (wavelength of 532?nm) in air. The surface morphology, structural and mechanical modification of irradiated targets was investigated by scanning electron microscopy (SEM) (Fei, Quanta 250), an X-ray diffractrometer (XRD) (DMAX III ARigaku, Japan) and a Vickers hardness tester, respectively. The SEM analysis revealed the exfoliation sputtering, electronic sputtering, thermal stresses and cracks. The grain size, dislocation line density, relative intensity and d-spacing of irradiated metals were studied by XRD. Micro hardness is found to increase with the increase in time of laser irradiation, in accordance with the Vickers hardness tester. This work provides a cost-effective, user-friendly and easy-to-handle study of several properties of irradiated targets with good results.  相似文献   
107.
108.
A mitochondria targeting dual-action platinumIV prodrug exhibits high anticancer activity in triple negative breast cancer cells. The complex intervenes in several cellular processes including DNA damage, perturbation of mitochondrial bioenergetics and induction of necrosis to kill cancer cells.  相似文献   
109.
Azobenzene-containing small molecules and polymers are functional photoswitchable molecules to form supramolecular nanomaterials for various applications. Recently, supramolecular nanomaterials have received enormous attention in material science because of their simple bottom-up synthesis approach, understandable mechanisms and structural features, and batch-to-batch reproducibility. Azobenzene is a light-responsive functional moiety in the molecular design of small molecules and polymers and is used to switch the photophysical properties of supramolecular nanomaterials. Herein, we review the latest literature on supramolecular nano- and micro-materials formed from azobenzene-containing small molecules and polymers through the combinatorial effect of weak molecular interactions. Different classes including complex coacervates, host-guest systems, co-assembled, and self-assembled supramolecular materials, where azobenzene is an essential moiety in small molecules, and photophysical properties are discussed. Afterward, azobenzene-containing polymers-based supramolecular photoresponsive materials formed through the host-guest approach, polymerization-induced self-assembly, and post-polymerization assembly techniques are highlighted. In addition to this, the applications of photoswitchable supramolecular materials in pH sensing, and CO2 capture are presented. In the end, the conclusion and future perspective of azobenzene-based supramolecular materials for molecular assembly design, and applications are given.  相似文献   
110.
A molecularly imprinting polymer (MIP) was synthesized for Basic Blue 3 dye and applied to wastewater for the adsorption of a target template. The MIPs were synthesized by bulk polymerization using methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA). Basic Blue 3 dye (BB-3), 2,2′-azobisisobutyronitrile (AIBN) and methanol were used as a functional monomer, cross linker, template, initiator and porogenic solvent, respectively, while non-imprinting polymers (NIP) were synthesized by the same procedure but without template molecules. The contact time was 25 min for the adsorption of BB-3 dye from 10 mL of spiked solution using 25 mg polymer. The adsorption of dye (BB-3) on the MIP followed the pseudo-second order kinetic (k2 = 0.0079 mg·g−1·min−1), and it was according to the Langmuir isotherm, with maximum adsorption capacities of 78.13, 85.4 and 99.0 mg·g−1 of the MIP at 283 K, 298 K and 313 K, respectively and 7 mg·g−1 for the NIP. The negative values of ΔG° indicate that the removal of dye by the molecularly imprinting polymer and non-imprinting polymer is spontaneous, and the positive values of ΔH° and ΔS° indicate that the process is endothermic and occurred with the increase of randomness. The selectivity of the MIP for BB-3 dye was investigated in the presence of structurally similar as well as different dyes, but the MIP showed higher selectivity than the NIP. The imprinted polymer showed 96% rebinding capacity at 313 K towards the template, and the calculated imprinted factor and Kd value were 10.73 and 2.62, respectively. In this work, the MIP showed a greater potential of selectivity for the template from wastewater relative to the closely similar compounds.  相似文献   
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