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141.
Clustering phenomenon has been studied in a film-deposition model in which a monolayer of particles is deposited onto a substrate. The occupation of a given site is assumed to depend on the occupation states of its nearest neighbouring sites as well as on the temperature of the particles being deposited. It is found that the percolating clusters remain ramified in that the number of their boundary sites are proportional to the number of particles in the cluster. The percolation threshold, however is lowered to (54±2)% as compared to 59% density for the uncorrelated case. 相似文献
142.
Nausheen Joondan Prakashanand Caumul 《Journal of Dispersion Science and Technology》2018,39(11):1550-1564
Amino acid-based amphiphiles have attracted much attention as environmentally friendly surfactants because of their biodegradability, low toxicity and the use of renewable sources of raw materials for their syntheses. With respect to molecular design, the amino acid-based architecture allows the possibilities of multiple structures of amphiphiles with varying head groups and chain lengths. This review focuses on the synthetic strategies for the development of various types of surfactants derived from amino acids. Their properties in terms of surface, biological and catalytic activities are illustrated. 相似文献
143.
Xiping Du Chun Wang Ling Wu Zhipeng Li Faizan Ahmed Sadiq Zedong Jiang Feng Chen Hui Ni Qingbiao Li 《Journal of separation science》2020,43(16):3206-3215
An effective two‐dimensional liquid chromatography method has been established for the analysis of all‐trans‐astaxanthin and its geometric isomers from Phaffia rhodozyma employing a C18 column at the first dimension and a C30 column in the second dimension, connected by a 10‐port valve using the photo‐diode array detector. The regression equation of astaxanthin calibration curve was established, and the precision and accuracy values were found to be in the range of 0.32–1.14% and 98.21–106.13%, respectively. By using two‐dimensional liquid chromatography, it was found that day light, ultrasonic treatment, and heat treatment have significant influence on the content of all‐trans‐astaxanthin in the extract from P. rhodozyma due to the transformation of all‐trans‐astaxanthin to cis‐astaxanthin. The day light and ultrasonic treatments more likely transform all‐trans‐astaxanthin to 9‐cis‐astaxanthin, and the thermal treatment transforms all‐trans‐astaxanthin to 13‐cis‐astaxanthin. These results indicate that the two‐dimensional liquid chromatography method can facilitate monitoring astaxanthin isomerization in the raw extract from P. rhodozyma. In addition, the study will provide a general reference for monitoring other medicals and bioactive chemicals with geometric isomers. 相似文献
144.
S. Sadiq Basha 《Optimization Letters》2011,5(4):639-645
Given non-void subsets A and B of a metric space and a non-self mapping T:A? B{T:A\longrightarrow B}, the equation T x = x does not necessarily possess a solution. Eventually, it is speculated to find an optimal approximate solution. In other words,
if T x = x has no solution, one seeks an element x at which d(x, T x), a gauge for the error involved for an approximate solution, attains its minimum. Indeed, a best proximity point theorem
is concerned with the determination of an element x, called a best proximity point of the mapping T, for which d(x, T x) assumes the least possible value d(A, B). By virtue of the fact that d(x, T x) ≥ d(A, B) for all x in A, a best proximity point minimizes the real valued function x? d(x, T x){x\longrightarrow d(x, T\,x)} globally and absolutely, and therefore a best proximity in essence serves as an ideal optimal approximate solution of the
equation T x = x. The aim of this article is to establish a best proximity point theorem for generalized contractions, thereby producing optimal
approximate solutions of certain fixed point equations. In addition to exploring the existence of a best proximity point for
generalized contractions, an iterative algorithm is also presented to determine such an optimal approximate solution. Further,
the best proximity point theorem obtained in this paper generalizes the well-known Banach’s contraction principle. 相似文献
145.
We propose a probabilistic strategy to upscale the material spatial variability from fine to coarse scale. To implement this idea in a numerical framework, we consider the coarse-scale as stochastic, i. e. its material properties are considered uncertain and modeled as random variables/fields. Numerical examples are shown to demonstrate the applicability of proposed approach. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
146.
I. Mohammed Sadiq Sunandan Pakrashi N. Chandrasekaran Amitava Mukherjee 《Journal of nanoparticle research》2011,13(8):3287-3299
In view of increasing commercial applications of metal oxide nanoparticles their toxicity assessment becomes important. Alumina
(Al2O3) nanoparticles have wide range of applications in industrial as well as personal care products. In the absence of prior report
on toxicological impact of alumina nanoparticles to microalgae, the principal objective of this study was to demonstrate the
effect of the nanoparticles on microalgae isolated from aquatic environment (Scenedesmus sp. and Chlorella sp.). The growth inhibitory effect of alumina nanoparticles was observed for both the species (72 h EC50 value, 45.4 mg/L for Chlorella sp.; 39.35 mg/L for Scenedesmus sp.). Bulk alumina also showed toxicity though to a lesser extent (72 h EC50 value, 110.2 mg/L for Chlorella sp.; 100.4 mg/L for Scenedesmus sp.). A clear decrease in chlorophyll content was observed in the treated cells compared to the untreated ones, more effect
being notable in the case of nanoparticles. Preliminary results based on FT-IR studies, optical and scanning electron microscopic
images suggest interaction of the nanoparticles with the cell surface. 相似文献
147.
This paper is aimed to study the tidal forces produced by a class of regular black holes. We consider the radial infall of test particle and find radial as well as angular components of tidal forces by taking geodesic deviation equations. We also compute geodesic deviation vector by solving geodesic deviation equation numerically. It is concluded that a particle undergos either compression or stretching in radial or angular direction due to tidal forces. 相似文献
148.
Fawad Mahmood Jamshaid Ali Khan Mater H. Mahnashi Muhammad Saeed Jan Muhammad Aamir Javed Umer Rashid Abdul Sadiq Syed Shams ul Hassan Simona Bungau 《Molecules (Basel, Switzerland)》2022,27(13)
In the current study, a series of new (2S,3S)-2-(4-isopropylbenzyl)-2-methyl-4-nitro-3-phenylbutanals (FM1-6) with their corresponding carboxylic acid analogues (FM7-12) has been synthesized. Initially, the aldehydic derivatives were isolated in the diastereomeric form, and the structures were confirmed with NMR, MS and elemental analysis. Based on the encouraging results in in vitro COX 1/2, 5-LOX and antioxidant assays, we oxidized the compounds and obtained the pure single (major) diastereomer for activities. Among all the compounds, FM4, FM10 and FM12 were the leading compounds based on their potent IC50 values. The IC50 values of compounds FM4, FM10 and FM12 were 0.74, 0.69 and 0.18 µM, respectively, in COX-2 assay. Similarly, the IC50 values of these three compounds were also dominant in COX-1 assay. In 5-LOX assay, the majority of our compounds were potent inhibitors of the enzyme. Based on the potency and safety profiles, FM10 and FM12 were subjected to the in vivo experiments. The compounds FM10 and FM12 were observed with encouraging results in in vivo analgesic and anti-inflammatory models. The molecular docking studies of the selected compounds show binding interactions in the minimized pocked of the target proteins. It is obvious from the overall results that FM10 and FM12 are potent analgesic and anti-inflammatory agents. 相似文献
149.
Journal of Thermal Analysis and Calorimetry - In this paper, the heat transfer in thin film flow on unsteady stretch plate of nanofluids is studied. The nanoparticles of copper Cu, alumina Al2O3... 相似文献
150.
Role of hybrid nanoparticles in thermal performance of peristaltic flow of Eyring–Powell fluid model
Riaz Arshad Ellahi R. Sait Sadiq M. 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1021-1035
Journal of Thermal Analysis and Calorimetry - Nanoparticles have great potential to improve thermophysical properties and thermal execution. At different polymer fixations, hybridization of... 相似文献