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101.
Michael Koch Mahmood Saleem Gernot Krammer 《Particle & Particle Systems Characterization》2007,24(6):431-439
The measurement of a distributed property is frequently encountered in engineering applications. The impact of a possible measurement error on the measured distribution is described and two methods to account for such an error are detailed: A Fourier transform based deconvolution procedure and a moment based deconvolution approach via kernel estimators are presented. The deconvolution methods can be used in many particle characterization and process applications where particle features or properties are commonly presented in a distributed form. In the current instance, these methods are carefully explored by using artificially generated data and applied to experimental data obtained from filter cake thickness measurements. 相似文献
102.
Bazzi Aicha Abbiche Khalid Izzaouihda Safia Acharjee Nivedita Zejli Hanane Marakchi Khadija Komiha Najia El Issami Souad Bazzi Lahcen Hilali Mustapha 《Structural chemistry》2021,32(6):2183-2198
Structural Chemistry - A combined experimental and theoretical study is presented to predict and analyze the inhibition efficiency and adsorption mechanism of 4-aminobenzoic acid molecule for... 相似文献
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Elia Merzari H. Ninokata A. Mahmood M. Rohde 《Theoretical and Computational Fluid Dynamics》2009,23(5):333-351
Geometries containing a narrow gap are characterized by strong quasi-periodical flow oscillations in the narrow gap region.
The above mentioned phenomena are of inherently unstable nature and, even if no conclusive theoretical study on the subject
has been published, the evidence shown to this point suggests that the oscillations are connected to interactions between
eddy structures of turbulent flows on opposite sides of the gap. These coherent structures travel in the direction of homogeneous
turbulence, in a fashion that strongly recalls a vortex street. Analogous behaviours have been observed for arrays of arbitrarily
shaped channels, within certain range of the geometric parameters. A modelling for these phenomena is at least problematic
to achieve since they are turbulence driven. This work aims to address the use of Proper Orthogonal Decomposition (POD) to
reduce the Navier–Stokes equations to a set of ordinary differential equations and better understand the dynamics underlying
these oscillations. Both experimental and numerical data are used to carry out the POD. 相似文献
105.
Muhammad Sultan Hajira Tahir Khalid Ahmed Qazi Jahanzeb 《Frontiers of Chemistry in China》2011,6(2):105-112
The kinetics of the reaction of Fast Green dye (FG) with cetylpyridinum chloride was studied in alkaline medium by UV-Visible
spectrophotometer. Reduction of Fast Green dye was carried out by varying the fast green dye concentration, cetylpyridinum
chloride concentration and concentration of sodium hydroxide. In the present study the reduction of dye was carried out in
order to reduce the color content. The interaction of dye was carried out with reducing analyte (cetylpyridinum chloride).
The rate of the reaction was determined by varying the above parameters at different temperatures. It was observed that the
reduction followed pseudo first-order kinetics with respect to dye, surfactant, OH− ion concentration according to the following reaction pathway. The mechanism for the photo bleaching of the dye has been
proposed and well confirmed by the data simulation procedure. The activation parameters of the reaction like entropy of activation
(ΔS) and free energy of activation (ΔG) showed the extremely solvated states of transient complex which was less disorderly arranged than the oxidized form of dye,
whereas E
a
values reflects a high amount of energy required for the reduction of dye with cetylpyridinum chloride. 相似文献
106.
Visible‐light‐driven photocatalytic degradation of fenpyroximate in rotating packed bed reactor using Fe3O4@PbS@Ni2P magnetic nanocomposite photocatalyst: Response surface modelling and optimization 下载免费PDF全文
107.
Khalid Bouras 《Rendiconti del Circolo Matematico di Palermo》1938,62(2):227-236
We introduce and study the class of almost Dunford–Pettis sets in Banach lattices. It also discusses some of the consequences derived from this study. As an application, we characterize Banach lattices whose relatively weakly compact sets are almost Dunford–Pettis sets. Also, we establish some necessary and sufficient conditions on which an almost Dunford–Pettis set is L-weakly compact (respectively, relatively weakly compact). In particular, we characterize Banach lattices under which almost Dunford–Pettis sets in the topological dual of a Banach lattice coincide with that of L-weakly compact (respectively, relatively weakly compact) sets. As a consequences we derive some results. 相似文献
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Abd Elmoneim O. Elkhalifa Eyad Al-Shammari Mohd Adnan Jerold C. Alcantara Khalid Mehmood Nagat Elzein Eltoum Amir Mahgoub Awadelkareem Mushtaq Ahmad Khan Syed Amir Ashraf 《Molecules (Basel, Switzerland)》2021,26(12)
Abelmoschus esculentus (Okra) is an important vegetable crop, widely cultivated around the world due to its high nutritional significance along with several health benefits. Different parts of okra including its mucilage have been currently studied for its role in various therapeutic applications. Therefore, we aimed to develop and characterize the okra mucilage biopolymer (OMB) for its physicochemical properties as well as to evaluate its in vitro antidiabetic activity. The characterization of OMB using Fourier-transform infrared spectroscopy (FT-IR) revealed that okra mucilage containing polysaccharides lies in the bandwidth of 3279 and 1030 cm−1, which constitutes the fingerprint region of the spectrum. In addition, physicochemical parameters such as percentage yield, percentage solubility, and swelling index were found to be 2.66%, 96.9%, and 5, respectively. A mineral analysis of newly developed biopolymers showed a substantial amount of calcium (412 mg/100 g), potassium (418 mg/100 g), phosphorus (60 mg/100 g), iron (47 mg/100 g), zinc (16 mg/100 g), and sodium (9 mg/100 g). The significant antidiabetic potential of OMB was demonstrated using α-amylase and α-glucosidase enzyme inhibitory assay. Further investigations are required to explore the newly developed biopolymer for its toxicity, efficacy, and its possible utilization in food, nutraceutical, as well as pharmaceutical industries. 相似文献