Biotemplating of BaFBr:Eu for X-ray storage phosphor applications

The design of hierarchically patterned novel structures by replicating the cellular tissue of wood has recently attained increasing interest. X-ray storage phosphor BaFBr:Eu²⁺ is manufactured via vacuum assisted repeated infiltration of wood tissue (Pinus sylvestris). A submicrometer precipitate is formed via wet chemical reaction of NH₄F, BaBr₂·2H₂O and EuCl₃·6H₂O in methanol. According to scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX), the original wood cell walls are filled with the precipitate and completely transformed into BaFBr struts after sintering at 800 °C. The optical properties of the biomorphous phosphor microstructure are determined by photoluminescence spectroscopy (PL) at room temperature, photo-stimulated luminescence spectroscopy (PSL) and cathodoluminescence spectroscopy (CL) in the SEM. A broadening of the PSL peak is observed and ascribed to the incorporation of calcium impurities present in the pine wood tissue. The potential of biotemplates for generating highly oriented and optically isolated μm- and sub-μm matrix of X-ray storage phosphor material is illustrated.     

Limited‐memory adaptive snapshot selection for proper orthogonal decomposition

Reduced order models are useful for accelerating simulations in many‐query contexts, such as optimization, uncertainty quantification, and sensitivity analysis. However, offline training of reduced order models (ROMs) can have prohibitively expensive memory and floating‐point operation costs in high‐performance computing applications, where memory per core is limited. To overcome this limitation for proper orthogonal decomposition, we propose a novel adaptive selection method for snapshots in time that limits offline training costs by selecting snapshots according an error control mechanism similar to that found in adaptive time‐stepping ordinary differential equation solvers. The error estimator used in this work is related to theory bounding the approximation error in time of proper orthogonal decomposition‐based ROMs, and memory usage is minimized by computing the singular value decomposition using a single‐pass incremental algorithm. Results for a viscous Burgers' test problem demonstrate convergence in the limit as the algorithm error tolerances go to zero; in this limit, the full‐order model is recovered to within discretization error. A parallel version of the resulting method can be used on supercomputers to generate proper orthogonal decomposition‐based ROMs, or as a subroutine within hyperreduction algorithms that require taking snapshots in time, or within greedy algorithms for sampling parameter space. Copyright © 2016 John Wiley & Sons, Ltd.     

Drug transport in stimuli responsive acrylic and methacrylic interpenetrating polymer networks

The interpenetrating polymer networks (IPNs) are recently gaining attention as sustained drug delivery systems because they could ensure a proper combination of functionality and network density to control the drug release profiles. This study aims to reveal how the functionality of two IPNs based on polyacrylamide and respectively poly(acrylic acid) (PAA) and poly(methacrylic acid) (PMAA) influences their smart behavior as well as their properties as delivery systems of the cationic drug verapamil hydrochloride (VPM). The “extra” α‐methyl group of PMAA results into a loss of the temperature sensitivity in the studied region and changes the pH responsivity of the PMAA/PAAM IPNs as compared to the PAA/PAAM IPNs. Moreover, the VPM diffusion in both IPNs depends on their composition due to the change in their functionality as well as of their network density. The “extra” α‐methyl group of PMAA defines its enhanced hydrophobicity and hence influences the VPM diffusion mechanism. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45380.     

Design and study of the potential of crosslinked cationic polymers as drug delivery systems for dermal application

Crosslinked carriers based on cationic monomer [2‐(acryloyloxy)ethyl]trimethylammonium chloride or 2‐(dimethylamino)ethyl methacrylate were developed and investigated as new platform for ibuprofen transdermal delivery. Series of networks of varied composition and structure were synthesized and characterized by FTIR spectroscopy and following swelling kinetics in different solvents. Dermal safety tests to examine the skin irritation and sensitization potential of the network films were performed in vivo. Chosen network compositions were loaded with ibuprofen by swelling in its ethanol solution. The structures of the drug carriers were investigated by scanning electron microscopy. Ibuprofen release from the developed drug delivery systems was followed in phosphate buffer solution at 37 °C. The investigation proved the feasibility of the developed cationic copolymer networks as effective platforms with modified ibuprofen release for potential dermal application. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46420.     

The state of psychological ownership: Integrating and extending a century of research.

People develop feelings of ownership for a variety of objects, material and immaterial in nature. We refer to this state as psychological ownership. Building on and extending previous scholarship, the authors offer a conceptual examination of this construct. After defining psychological ownership, they address "why" it exists and "how" it comes into being. They propose that this state finds its roots in a set of intraindividual motives (efficacy and effectance, self-identity, and having a place to dwell). In addition, they discuss the experiences that give rise to psychological ownership and propose several positive and negative consequences of this state. The authors' work provides a foundation for the development of a comprehensive theory of psychological ownership and the conceptual underpinnings for empirical testing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Biochemical and technological characteristics of the milk from Black-and White Dutch]

Studied were the composition and the technologic properties of the milk of Dutch Black pied cattle under this country's conditions. Milk samples were taken for analysis once in a month on a cow farm founded in 1964 with a total of 67 impregnated heifers and having at the time of investigation 88 cows, twelve of them remaining from the initial animals imported from Holland and the others being the offspring of the herd. It was established that the annual milk yield per forage cow, amounting to 44881 has the following index values; dry matter--12.63 +/- 0.48 per cent; butterfat per cent--4.07 +/- 0.2%; total protein--3.37 +/- 0.16 per cent; casein--2.56 +/- 0.16; slids-nonfat--8.54 +/- 0.24 per cent; calcium--0.126 +/- 0.002 per cent; phosphorus--0.079 +/- 0.003 per cent. The technologic properties of milk proved unsatisfactory: coagulation capacity--359 s; rheologic value--112.93 X 1.10(-5) V/cm3; and technologic coeficient--1.32. The data on the composition and the technologic properties of Dutch Black-pied cow's milk showed, on the whole, that most profitable is its processing into butter as against processing into cheese in which case the yields would be unsatisfactory.     

Toluene oxidation on titanium- and iron-modified MCM-41 materials

Iron- and titanium-modified MCM-41 materials, prepared by direct synthesis at ambient temperature or wet impregnation technique, were investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM), temperature-programmed reduction (TPR), UV–vis diffuse reflectance, Mössbauer and FT-IR spectroscopies. Their catalytic behavior was studied in total oxidation of toluene. Materials with high surface area and well-ordered pore structure were obtained. The increase of the titanium content (up to 50%) in the bisubstituted, iron and titanium containing materials leads to partial structure collapse of the silica matrix. Finely dispersed anatase particles were also formed during the impregnation procedure. The catalytic activity of the bisubstituted materials was influenced by the method of their preparation, but higher catalytic stability could be achieved, compared to iron monosubstituted one. The nature of the catalytic active sites is discussed.     

Study of the Fixed‐Bed Adsorption Behavior of Phenylalanine on Solvent Impregnated Resins,Part III

Abstract

The implementation of the SIR technique for the amino acid separation from diluted aqueous solutions in a fixed‐bed column is presented and a mathematical model for the prediction of the adosrption behavior is developed. Independently determined equilibrium and kinetic parameters are used for the calculation of the breakthrough curves. Fixed‐bed parameters, such as axial dispersion and bed porosity, are determined experimently and compared with correlations. Analysis of the Biot and Bodenstein number reveal that the mass transfer through the film liquid around the particles, as well as the axial dispersion in the column, could be neglected at the studied experimental conditions. A simplified mathematical model was found to give the best prediction to the experimental breakthrough curves over a wide range of feed concentrations and flow rates.