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101.
Iuliana Spiridon Ramona Gabriela Ursu Irene Alexandra Cianga Spiridon 《International Journal of Polymer Analysis and Characterization》2015,20(8):681-692
The interest in antimicrobial packaging materials based on polylactic acid (PLA) polymers has increased due to the need to improve food safety and environment quality and also to find alternatives to synthetic polymers made from petrochemicals. PLA films by addition of different fillers (grape wastes and celery fibers) were obtained. The mechanical, thermal, surface, and antimicrobial properties of the films were evaluated. The incorporation of inexpensive fillers into the PLA matrix could reduce costs and the studied formulations offer approaches to realize composites with high performances and antimicrobial response, suitable for film food-active packaging materials, especially by use of grape wastes. 相似文献
102.
Nicolae Dan Tesloianu Lucian Dobreci Vlad Ghizdovat Andrei Zala Adrian Valentin Cotirlet Alina Gavrilut Maricel Agop Decebal Vasincu Igor Nedelciuc Cristina Marcela Rusu Irina Iuliana Costache 《Entropy (Basel, Switzerland)》2021,23(4)
By assimilating biological systems, both structural and functional, into multifractal objects, their behavior can be described in the framework of the scale relativity theory, in any of its forms (standard form in Nottale’s sense and/or the form of the multifractal theory of motion). By operating in the context of the multifractal theory of motion, based on multifractalization through non-Markovian stochastic processes, the main results of Nottale’s theory can be generalized (specific momentum conservation laws, both at differentiable and non-differentiable resolution scales, specific momentum conservation law associated with the differentiable–non-differentiable scale transition, etc.). In such a context, all results are explicated through analyzing biological processes, such as acute arterial occlusions as scale transitions. Thus, we show through a biophysical multifractal model that the blocking of the lumen of a healthy artery can happen as a result of the “stopping effect” associated with the differentiable-non-differentiable scale transition. We consider that blood entities move on continuous but non-differentiable (multifractal) curves. We determine the biophysical parameters that characterize the blood flow as a Bingham-type rheological fluid through a normal arterial structure assimilated with a horizontal “pipe” with circular symmetry. Our model has been validated based on experimental clinical data. 相似文献
103.
Mihaela Avadanei Mioara Drobota Iuliana Stoica Elena Rusu Virgil Barboiu 《Journal of polymer science. Part A, Polymer chemistry》2010,48(23):5456-5467
Surface of biaxially oriented poly(ethylene terephthalate) films was chemically modified by exposure to ethylenediamine (EDA), triethylenetetramine (TETA), and tetraethylenepentamine (TEPA) for different treatment times. Variable angle attenuated total reflection Fourier transform infrared (ATR‐FTIR) spectroscopy was used in conjunction with weight loss measurements, scanning electron microscopy (SEM), and atomic force microscopy to establish the surface modification and to draw the depth profile of the newly created species, with emphasis on amide group. A clear differentiation was found between the effects of the three amines studied: EDA produces the highest amidation degree but, because of its deep penetration into the film, leads to delamination of rather thick layers, TETA reacts at and near surface and develops surface cracks without delamination, and TEPA is the mildest reactant, generating amide groups on the surface without visible deterioration of the sample. It was proved that the amide II absorption band became weaker with increasing analyzed depth, with a pronounced heterogeneity near the surface. SEM micrographs showed the development of cracks onto the surface at longer aminolysis time, which allowed a better understanding of ATR‐FTIR observations. Assuming an exponential decay for the depth profile spectrally obtained, the surface concentration of amide groups and the decay constant were determined for the amines and reaction times used. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
104.
Variously substituted novel dihydropyridoazepinones have been prepared by an intermolecular radical addition followed by a radical cyclisation on a pyridine ring. The latter process involved the use of a combination of two different peroxides, an experimental contrivance resulting from a careful product analysis and a better understanding of the cyclisation step. 相似文献
105.
This study aims to evidence the influence of polyelectrolytes structure and the number of double layers on the properties
of some new nanostructured architectures formed by layer-by-layer self-assembly of complementary weak polyelectrolytes on
planar surfaces. For this purpose, we used chitosan and poly(allylamine hydrochloride) as polycations, and poly(acrylic acid)
and poly(2-acrylamido-2-methylpropanesulfonic acid–co-acrylic acid) as polyanions. To get a direct image on the polyelectrolyte
multilayers formation and properties, gravimetry, infrared spectroscopy, and atomic force microscopy have been used. The capacity
of the polyions to overcompensate the complementary polyions charges, and thus to influence the swelling degree in water of
thin films, was strongly influenced by the chain structure and flexibility. A special attention was paid to the responsiveness
of the new composite materials to the pH of the swelling environment. 相似文献
106.
Vlad Tiberiu Alexa Atena Galuscan Codrua M. Soica Antoanela Cozma Dorina Coricovac Florin Borcan Iuliana Popescu Alexandra Mioc Camelia Szuhanek Cristina Adriana Dehelean Daniela Jumanca 《Molecules (Basel, Switzerland)》2022,27(3)
Medicinal plants and essential oils (EOs), in particular, were intensively studied in recent years as viable alternatives for antiproliferative chemical synthetic agents. In the same lines, the present study focuses on investigating the effects of natural preparations (emulsions) based on EOs obtained from Citrus bergamia Risso (bergamot-BEO), Citrus sinensis Osbeck (orange-OEO), and Syzygium aromaticum Merill et L. M. Perry (clove-CEO) on different healthy (human immortalized keratinocytes—HaCaT and primary human gingival fibroblasts—HGF) and human tumor cell lines (human melanoma—A375 and oral squamous carcinoma—SCC-4) in terms of the cells’ viability and cellular morphology. The obtained results indicate that the CEO emulsion (ECEO) induced a dose-dependent cytotoxic in both healthy (HaCaT and HGF) and tumor (A375 and SCC-4) cells. OEO emulsion (EOEO) increased cell viability percentage both for HaCaT and A375 cells and had an antiproliferative effect at the highest concentration in HGF and SCC-4 cells. BEO emulsion (EBEO) decreased the viability percentage of SCC-4 tumor cells. By associating OEO with CEO as a binary mixture in an emulsified formulation, the inhibition of tumor cell viability increases. The E(BEO/OEO) binary emulsion induced an antiproliferative effect on oral health and tumor cells, with a minimal effect on skin cells. The non-invasive tests performed to verify the safety of the test compound’s emulsions at skin level indicated that these compounds do not significantly modify the physiological skin parameters and can be considered safe for human skin. 相似文献
107.
Racles Carmen Airinei Anton Stoica Iuliana Ioanid Aurelia 《Journal of nanoparticle research》2010,12(6):2163-2177
Journal of Nanoparticle Research - Silver nanoparticles were obtained in aqueous medium, at room temperature, by redox reactions, with or without glucose, in the presence of a glucose-containing... 相似文献
108.
Adrian Carabineanu Adrian Dinu Iuliana Oprea 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1995,46(6):971-981
A boundary element method is developed in order to investigate the flow of viscous, incompressible, electrically conducting fluids in cylindrical ducts having arbitrary cross-sections. The numerical results obtained for the circular duct with insulating wall are very close to the results obtained by means of analytical formulas. 相似文献
109.
Prof. Dr. C. Drăgulescu E. Petrovici Iuliana Lupu 《Monatshefte für Chemie / Chemical Monthly》1974,105(6):1170-1175
Hexachloroantimonates with nitroderivatives as ligands on the cations are formed in a double complexation reaction of a mono-valent metal chloride (LiCl, NaCl, KCl, CuCl) with SbCl5, and a nitroderivativeL (nitromethane, nitrobenzene, α-nitronaphthalene). Solid complexes of the typeML(SbCl6) andML 2(SbCl6) were isolated. Synthesis, analytical results andi.r. spectra are discussed. 相似文献
110.
Rueping M Uria U Lin MY Atodiresei I 《Journal of the American Chemical Society》2011,133(11):3732-3735
Chiral contact ion-pair catalysis with particular focus on metal-free processes is gaining in interest. As a result, new perspectives are opened, and highly stereoselective transformations, traditionally performed under metal catalysis, can be realized. Herein, we report the development of an unprecedented asymmetric Br?nsted acid-catalyzed allylic alkylation. The concept relies on chiral contact ion-pair catalysis, in which the chiral organic counteranion of an allylic carbocation induces high enantioselectivities and allows access to biologically relevant chromenes in good yields and with excellent enantioselection. 相似文献