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31.
N. Neibolts O. Platnieks S. Gaidukovs A. Barkane V.K. Thakur I. Filipova G. Mihai Z. Zelca K. Yamaguchi M. Enachescu 《Materials Today Chemistry》2020
Sustainable materials have slowly overtaken the nanofiber research field while the tailoring of their properties and the upscaling for industrial production are some of the major challenges. We report preparation of nanofibers that are bio-based and biodegradable prepared from poly (butylene succinate) (PBS) with the incorporation of nanofibrillated cellulose (NFC) and graphene nanoplatelets (GN). NFC and GN were combined as hybrid filler, which led to the improved morphological structure for electrospun nanofibers. A needleless approach was used for solution electrospinning fabrication of nanofiber mesh structures to promote application scalability. The polymer crystallization process was examined by differential scanning calorimetry (DSC), the thermal stability was evaluated by thermal gravimetric analysis (TGA), while the extensive investigation of the nanofibers structure was carried out with scanning electron microscopy (SEM) and atomic force microscopy (AFM). NFC and GN loadings were 0.5 and 1.0 wt %; while poly (ethylene glycol) (PEG) was employed as a compatibilizer to enhance fillers’ interaction within the polymer matrix. The interactions in the interface of the fillers and matrix components were studied by FTIR and Raman spectroscopies. The hybrid filler approach proved to be most suitable for consistent and high-quality nanofiber production. The obtained dense mesh-based structures could have foreseeable potential application in biomedical field like scaffolds for the tissue and bone recovery, while other applications could focus on filtration technologies and smart sensors. 相似文献
32.
Ana Maria Toader Maria Cristina Buta Alice Mischie Mihai V. Putz Fanica Cimpoesu 《Molecules (Basel, Switzerland)》2022,27(1)
Aromatic hydrocarbons with fused benzene rings and regular triangular shapes, called n-triangulenes according to the number of rings on one edge, form groundstates with n-1 unpaired spins because of topological reasons. Here, we focus on methodological aspects emerging from the density functional theory (DFT) treatments of dimer models of the n = 2 triangulene (called also phenalenyl), observing that it poses interesting new problems to the issue of long-range corrections. Namely, the interaction comprises simultaneous spincoupling and van der Waals effects, i.e., a technical conjuncture not considered explicitly in the benchmarks calibrating long-range corrections for the DFT account of supramolecular systems. The academic side of considering dimer models for calculations and related analysis is well mirrored in experimental aspects, and synthetic literature revealed many compounds consisting of stacked phenalenyl cores, with intriguing properties, assignable to their long-range spin coupling. Thus, one may speculate that a thorough study assessing the performance of state-of-the-art DFT procedures has relevance for potential applications in spintronics based on organic compounds. 相似文献
33.
Mihai Răducă Cristian D. Ene Sorana Ionescu Mihaela Florea 《Journal of Coordination Chemistry》2019,72(8):1222-1237
Abstract1-D coordination polymers, 1∞[Zn(fl)2]·2EtOH and 1∞[Zn(fl)2]·2MeOH, and a dinuclear complex, [{Zn(fl)2}2(dienpip)]·4H2O·4EtOH (dienpip?= N,N′-bis(2-aminoethyl)piperazine), were obtained using Zn(II) ions and fluorescein anions (fl). Thermal analysis shows stability of the polymers after solvent removal up to more than 400?°C. Crystallization solvent molecules were removed under reduced pressure with the preservation of the polymeric structure, 1∞[Zn(fl)2]. Desolvated crystals were exposed to I2 vapors and the crystal structure determination by X-ray diffraction confirmed the presence of I2 molecules in the channels generated in crystals by the metal-organic framework. The iodine content, evaluated by X-ray diffraction, corresponds to the overall formula 1∞[Zn(fl)2]·0.3I2. The optical properties of the coordination polymers and the dinuclear complex have been investigated. 相似文献
34.
Nagi Reddy Vanga Anudeep Kota Ramakrishna Sistla Mallavadhani Uppuluri 《Molecular diversity》2017,21(2):273-282
35.
Ciprian Dragan Adrian Samuila Subhankar Das Dan Iancu Mihai Bilici Lucian Dascalescu 《Journal of Electrostatics》2009,67(2-3):184-188
The aim of this study is to refine the understanding of the tribo-electrostatic phenomena that can affect the efficiency of suction-type dilute-phase transport systems. The study was conducted with mm-size ABS-PC particles, a granular material originating from genuine information technology wastes. The tribo-charging process was modelled using the response surface method of experimental design. The controlled variables were the granular material feed rate and the aspirating air speed rate. The monitored variable was the charge imparted to a well-defined section of the duct and which is equal to the charge transferred to the particles passing through that section of the pneumatic transport system. An induction type sensor connected to an electrometer has been employed for the measurements. The data were processed by a virtual instrument developed in LabView. A commercial software package was employed for estimating the effects of the various factors and predicting the optimum operating conditions, which were then confirmed by a final experiment. 相似文献
36.
The first total synthesis of Pestalotioprolide C and C7-epi-Pestalotioprolide C adopting Noyori asymmetric reduction, HWE Olefination and Shiina macrolactonization as the key steps has been described. 相似文献
37.
Mihai Mari 《Journal de Mathématiques Pures et Appliquées》2002,81(12):109-1239
We are interested in the existence of travelling-waves for the nonlinear Schrödinger equation in RN with “ψ3−ψ5”-type nonlinearity. First, we prove an abstract result in critical point theory (a local variant of the classical saddle-point theorem). Using this result, we get the existence of travelling-waves moving with sufficiently small velocity in space dimension N4. 相似文献
38.
M. C. Reddy B. P. Nagi Reddy K. R. Sridharan J. Ramakrishna 《Magnetic resonance in chemistry : MRC》1984,22(7):464-467
From consideration of 1H–1H vicinal coupling constants and 13C? 1H long-range coupling constants in a series of amino acid derivatives, the precise values of 13C component vicinal coupling constants have been calculated for the three minimum energy staggered rotamers for the C(α)H? C(β)H2 side-chains of amino acids. 相似文献
39.
M. Petrascu A. Isbasescu I. Lazar I. Mihai H. Petrascu A. T. Rudchik V. A. Chernievski O. A. Ponkratenko V. A. Ziman 《Zeitschrift für Physik A Hadrons and Nuclei》1993,345(4):395-399
The energy spectra and angular distributions of products in the reaction27Al(14N,X) have been measured at 116 MeV bombarding energy. It is shown that the energy spectra of the products lighter than the projectile, are well described by a three-body breakup calculation. The experimental total breakup cross-section estimated in the present work, together with Glas-Mosel calculation of the fusion cross-section, are in a reasonable agreement with the optical model total reaction cross-section. 相似文献
40.