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da Silva Andre Luis Ferreira Salas Ruben Andres Silva Emilio Carlos Nelli 《Meccanica》2021,56(2):417-437
Meccanica - Fiber reinforced materials are used in assorted engineering application and for this reason, new additive manufacturing technologies have been developed for this type of materials. With... 相似文献
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Yalda Liaghati Mobarhan Ronald Soong Daniel Lane Andre J. Simpson 《Magnetic resonance in chemistry : MRC》2020,58(5):427-444
Traditionally, due to different hardware requirements, nuclear magnetic resonance (NMR) has developed as two separate fields: one dealing with solids, and one with solutions. Comprehensive multiphase (CMP) NMR combines all electronics and hardware (magic angle spinning [MAS], gradients, high power Radio Frequency (RF) handling, lock, susceptibility matching) into a universal probe that permits a comprehensive study of all phases (i.e., liquid, gel-like, semisolid, and solid), in intact samples. When applied in vivo, it provides unique insight into the wide array of bonds in a living system from the most mobile liquids (blood, fluids) through gels (muscle, tissues) to the most rigid (exoskeleton, shell). In this tutorial, the practical aspects of in vivo CMP NMR are discussed including: handling the organisms, rotor preparation, sample spinning, water suppression, editing experiments, and finishes with a brief look at the potential of other heteronuclei (2H, 15N, 19F, 31P) for in vivo research. The tutorial is aimed as a general resource for researchers interested in developing and applying MAS-based approaches to living organisms. Although the focus here is CMP NMR, many of the approaches can be adapted (or directly applied) using conventional high-resolution magic angle spinning, and in some cases, even standard solid-state NMR probes. 相似文献
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Kondakov N. N. Mel´nikova T. M. Chekryzhova T. V. Mel´nikova M. V. Zinin A. I. Torgov V. I. Chizhov A. O. Kononov L. O. 《Russian Chemical Bulletin》2015,64(5):1142-1148
Russian Chemical Bulletin - Terminal disaccharide fragment of phenolic glycolipid from Mycobacterium leprae (PGL-I) was synthesized as a glycoside with 4-(2-aminoethoxy)phenyl aglycon. The obtained... 相似文献
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Tatiana Monaretto Andre Souza Tiago Bueno Moraes Victor Bertucci-Neto Corinne Rondeau-Mouro Luiz Alberto Colnago 《Magnetic resonance in chemistry : MRC》2019,57(9):616-625
The traditional way to enhance signal-to-noise ratio (SNR) of nuclear magnetic resonance (NMR) signals is to increase the number of scans. However, this procedure increases the measuring time that can be prohibitive for some applications. Therefore, we have tested the use of several post-acquisition digital filters to enhance SNR up to one order of magnitude in time domain NMR (TD-NMR) relaxation measurements. The procedures were studied using continuous wave free precession (CWFP-T1) signals, acquired with very low flip angles that contain six times more noise than the Carr–Purcell–Meiboom–Gill (CPMG) signal of the same sample and experimental time. Linear (LI) and logarithmic (LO) data compression, low-pass infinity impulse response (LP), Savitzky–Golay (SG), and wavelet transform (WA) post-acquisition filters enhanced the SNR of the CWFP-T1 signals by at least six times. The best filters were LO, SG, and WA that have high enhancement in SNR without significant distortions in the ILT relaxation distribution data. Therefore, it was demonstrated that these post-acquisition digital filters could be a useful way to denoise CWFP-T1, as well as CPMG noisy signals, and consequently reducing the experimental time. It was also demonstrated that filtered CWFP-T1 method has the potential to be a rapid and nondestructive method to measure fat content in beef and certainly in other meat samples. 相似文献
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Florin Radu Alexei Nefedov Johannes GrabisGregor Nowak Andre BergmannHartmut Zabel 《Journal of magnetism and magnetic materials》2006
We have used soft X-ray resonant magnetic scattering (XRMS) to search for the presence of an effective ferromagnetic moment belonging to the antiferromagnetic (AF) layer which is in close contact with a ferromagnetic (F) layer. Taking advantage of the element specificity of the XRMS technique, we have measured hysteresis loops of both Fe and CoO layers of a CoO(40 Å)/Fe (150 Å) exchange bias bilayer. From these measurements we have concluded that the proximity of the F layer induces a magnetic moment in the AF layer. The F moment of the AF layer has two components: one is frozen and does not follow the applied magnetic field and the other one follows in phase the ferromagnetic magnetization of the F layer. The temperature dependence of the F components belonging to the AF layer is shown and discussed. 相似文献
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Jean Ravez Re´gnault Von Der Mu¨hll Paul Hagenmuller 《Journal of solid state chemistry》1975,14(1):20-24
Au sein d'un re´seau de type BaFeF5 des chai?nes d'octae`dres fluore´sa`sommets communs peuvent disparai?tre en donnant naissance a des canaux dont l'occupation partielle ou totale par des files de cations Sr2+ et de couples d'anions F?, conduit respectivement aux phases Sr3(FeF6)2 ou Sr5T3F19 (T = Cr, Co, Ga). Une discussion cristallochimique permet d'expliquer l'existence d'un domaine de solutions solides au sein du diagramme ternaire SrF2BaF2FeF3. 相似文献
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