Explicit finite difference simulations for accelerating cross diffusion flow over a perpendicular shield with parabolic motion

The heat transfer phenomenon subject to thermos-diffusion effects convey important applications in the heating processes, extrusion systems, chemical processes and various engineering systems. The objective of current work is to observe the contribution of Soret and Dufour effects in oscillating shield for cross diffusion flow. The perpendicular shield with oscillating motion induced the flow. The magnitude of oscillations is assumed to be small so that laminar flow due to oscillating shield has been resulted. The motivations for addressing the thermos-diffusion phenomenon due to oscillating of shield are due to applications in oscillatory pumps, moving surface, metal detectors, power systems etc. The dimensionless problem is obtained via introducing the appropriate set of variables. The numerical outcomes are suggested by using the most interesting explicit finite difference scheme. The physical illustration for flow parameters is presented. Moreover, the aspect of physical quantities involving the flow are graphically reported.     

Synthesis of platinum complexes containing (+)-bornyl- and (−)-menthylammonium in the outer coordination sphere and their catalytic activity in hydrosilylation reactions

Optically active (+)-bornyl- and (−)-menthylammonium platinates were synthesized starting from H₂[PtCl₆] · 4H₂O and hydrochlorides of the corresponding amines. Catalytic activity of the complexes in the hydrosilylation reactions of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane with 1,1,3,3-tetramethyldisiloxane and acetophenone with diphenylsilane was studied. The addition of the siloxanes leads to a predominant formation of β-adduct. Activity of the catalysts, evaluated on the 50% conversion of the substrate, decreases in the following sequence: (−)-(menthylNH₃)₂[PtCl₆] > (Et₃NH)₂[PtCl₆] > (+)-(bornylNH₃)₂[PtCl₄] > (+)-(bornylNH₃)₂[PtCl₆]. Asymmetric induction is observed in the hydrosilylation of aceto-phenone in the presence of (+)-(bornylNH₃)₂[PtCl _n ] (n = 4, 6); (+)-(bornylNH₃)₂[PtCl₆] showed the highest catalytic activity and selectivity. The hydrosilylation of acetophenone gave 1-phenylethoxy(diphenyl)silane, 1-phenylvinyloxy(diphenyl)silane, and 2-phenylethyl-2-diphenylsiloxy(diphenyl)silane as the products. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 341–349, February, 2008.     

Effect of Antioxidant System on Aging Properties of Poly(1-butene) and the Aging Mechanism

The aging property of poly(1-butene) in which different antioxidant systems were added was characterized by its physical and mechanical properties before and after aging for 300 h in a hot air aging box. In addition, the oxidation induction time (OIT) of all designed samples was tested. The result demonstrated that the primary antioxidant pentaerythritol tetrakys 3-(3,5-ditert-butyl-4-hydroxyphenyl) propionate performed better than n-octadecyl-β-(4-hydroxy-3,5-di-tert -butyl-phenyl)-propionate. The anti-aging effect of the secondary antioxidant was ranked in the order bis-(2,4-di-tert-butyl-pheny)-phosphiterythritol diphosphite better than tns-(2.4-di-tert-butyl)-phosphite, with both better than distearyl thiodipropionic acid. Confirmation of oxidation of the polymer was made by IR analysis and a general oxidation mechanism scheme for poly(1-butene) is presented.     

Stabilized nodal‐based finite element methods for the magnetic induction problem

We consider the time‐dependent magnetic induction model as a step towards the resistive magnetohydrodynamics model in incompressible media. Conforming nodal‐based finite element approximations of the induction model with inf‐sup stable finite elements for the magnetic field and the magnetic pseudo‐pressure are investigated. Based on a residual‐based stabilization technique proposed by Badia and Codina, SIAM J. Numer. Anal. 50 (2012), pp. 398–417, we consider a stabilized nodal‐based finite element method for the numerical solution. Error estimates are given for the semi‐discrete model in space. Finally, we present some examples, for example, for the magnetic flux expulsion problem, Shercliff's test case and singular solutions of the Maxwell problem. Copyright © 2015 John Wiley & Sons, Ltd.     

Poly(glycidyl methacrylate)‐grafted hydrophobic charge‐induction agarose resins with 5‐aminobenzimidazole as a functional ligand

Hydrophobic charge‐induction chromatography is a new technology for antibody purification. To improve antibody adsorption capacity of hydrophobic charge‐induction resins, new poly(glycidyl methacrylate)‐grafted hydrophobic charge‐induction resins with 5‐aminobenzimidazole as a functional ligand were prepared. Adsorption isotherms, kinetics, and dynamic binding behaviors of the poly(glycidyl methacrylate)‐grafted resins prepared were investigated using human immunoglobulin G as a model protein, and the effects of ligand density were discussed. At the moderate ligand density of 330 μmol/g, the saturated adsorption capacity and equilibrium constant reached the maximum of 140 mg/g and 25 mL/mg, respectively, which were both much higher than that of non‐grafted resin with same ligand. In addition, effective pore diffusivity and dynamic binding capacity of human immunoglobulin G onto the poly(glycidyl methacrylate)‐grafted resins also reached the maximum at the moderate ligand density of 330 μmol/g. Dynamic binding capacity at 10% breakthrough was as high as 76.3 mg/g when the linear velocity was 300 cm/h. The results indicated that the suitable polymer grafting combined with the control of ligand density would be a powerful tool to improve protein adsorption of resins, and new poly(glycidyl methacrylate)‐grafted hydrophobic charge‐induction resins have a promising potential for antibody purification applications.     

Generalized solvability and optimization of a parabolic system with a discontinuous solution

We consider the following linear parabolic system in a domain with a thin low-permeable insertion (“imperfect interface”):

     

Asymptotic behavior of positive solutions for heat equation with nonlinear term

We study the nonlinear parabolic equation , in Rn×(0,∞) with boundary condition u(x,0)=u₀(x), not necessarily bounded function. The nonlinearity φ((x,t),u) is required to satisfy some conditions related to the parabolic Kato class P^∞(Rn) while allowing existence of positive solutions of the equation and continuity of such solutions. Our approach is based on potential theory tools.     

Clerodane Diterpenoids from an Edible Plant Justicia insularis: Discovery,Cytotoxicity, and Apoptosis Induction in Human Ovarian Cancer Cells

Objectives: The toxicity of chemotherapeutic anticancer drugs is a serious issue in clinics. Drug discovery from edible and medicinal plants represents a promising approach towards finding safer anticancer therapeutics. Justicia insularis T. Anderson (Acanthaceae) is an edible and medicinal plant in Nigeria. This study aims to discover cytotoxic compounds from this rarely explored J. insularis and investigate their underlying mechanism of action. Methods: The cytotoxicity of the plant extract was evaluated in human ovarian cancer cell lines and normal human ovarian surface epithelia (HOE) cells using a sulforhodamine B assay. Bioassay-guided isolation was carried out using column chromatography including HPLC, and the isolated natural products were characterized using GC-MS, LC-HRMS, and 1D/2D NMR techniques. Induction of apoptosis was evaluated using Caspase 3/7, 8, and 9, and Annexin V and PI based flow cytometry assays. SwissADME and SwissTargetPrediction web tools were used to predict the molecular properties and possible protein targets of identified active compounds. Key finding: The two cytotoxic compounds were identified as clerodane diterpenoids: 16(α/β)-hydroxy-cleroda-3,13(14)Z-dien-15,16-olide (1) and 16-oxo-cleroda-3,13(14)E-dien-15-oic acid (2) from the Acanthaceous plant for the first time. Compound 1 was a very abundant compound (0.7% per dry weight of plant material) and was shown to be more potent than compound 2 with IC₅₀ values in the micromolar range against OVCAR-4 and OVCAR-8 cancer cells. Compounds 1 and 2 were less cytotoxic to HOE cell line. Both compounds induced apoptosis by increasing caspase 3/7 activities in a concentration dependent manner. Compound 1 further increased caspase 8 and 9 activities and apoptosis cell populations. Compounds 1 and 2 are both drug like, and compound 1 may target various proteins including a kinase. Conclusions: Clerodane diterpenoids (1 and 2) in J. insularis were identified as cytotoxic to ovarian cancer cells via the induction of apoptosis, providing an abundant and valuable source of hit compounds for the treatment of ovarian cancer.     

复杂显示中诱导域彩度对目标色貌的影响

用双目不对称匹配法测试了在复杂显示中目标色貌与其周围诱导域彩度的关系。结果表明：当保持目标与周围的色调相同且亮度不变,只改变诱导域的彩度时,色诱导引起的目标色觉位移的大小随诱导域彩度的增加而增加,色觉位移的方向大多数不随诱导域彩度改变,基本指向该色调彩度降低的方向。     

动生、感生电动势与法拉第电磁感应定律

从法拉第电磁感应定律出发证明了闭合线圈的感应电动势是感生电动势与动生电动势之和