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111.
Three‐dimensional (3D) printing becomes an attractive technique to fabricate tissue engineering scaffolds through its high control on fabrication and repeatability using the printing parameters. This technique can be combined by the finite element method (FEM), and tissue‐specific scaffolds with desirable morphological and mechanical properties can be designed and manufactured. In this study, the influential 3D printing parameters on the morphological and mechanical properties of polycaprolactone (PCL) filament and scaffold were studied experimentally and numerically. First, the effects of printing parameters and process on the properties of extruded PCL filament were investigated. Then, using FEM, the effects of filament specifications on the overall characteristics of the scaffold were evaluated. Results showed that both the printing process in terms of resting time and remaining time and the printing parameters like pressure, printing speed, and printing path length have influenced the filament properties. In addition, both the filament diameter and elastic modulus had significant effects on the properties of scaffold especially, a 20% increase in the filament diameter caused the scaffold compressive elastic modulus to rise by around 72%. It is concluded that the printing parameters and process must be tuned very well in fabricating scaffolds with the desired morphology and mechanical property. 相似文献
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113.
Inês R. Ramos Fiona M. Lyng Ihtesham Ur Rehman Basil Sharrack M. Nicola Woodroofe 《应用光谱学评论》2017,52(10):868-882
Spectroscopy techniques are valuable tools in biomedical research and have been used extensively in the study of disease. However, neurological conditions such as multiple sclerosis (MS) have received little attention and the available spectroscopy studies are limited, both in overall numbers of patients studied and the disease samples considered. MS is a complex immune-mediated disease, with variable clinical courses and limited therapeutic options. This review aims to summarize current literature in the area, demonstrating how spectroscopy techniques can provide valuable information to inform and advance research into the most common neurological condition affecting young adults. 相似文献
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Costas Iliopoulos M. Sohel Rahman Michal Voráček Ladislav Vagner 《Journal of Discrete Algorithms》2010,8(2):117-130
In this paper, we present linear-time algorithms for the construction two novel types of finite automata and show how they can be used to efficiently solve the Longest Common Subsequence (LCS), Shortest Common Supersequence (SCS) and Constrained Longest Common Subsequence (CLCS) problems for degenerate strings. 相似文献
116.
C. Andreoiu M. Axiotis G. de Angelis J. Ekman C. Fahlander E. Farnea A. Gadea T. Kröll S.M. Lenzi N. Mărginean T. Martinez M.N. Mineva C. Rossi Alvarez D. Rudolph C.A. Ur 《The European Physical Journal A - Hadrons and Nuclei》2002,15(4):459-462
Excited states in 59Zn were observed for the first time following the fusion-evaporation reaction 24Mg + 40Ca at a beam energy of 60 MeV. The GASP array in conjunction with the ISIS Silicon ball and the NeutronRing allowed for the
detection of γ-rays in coincidence with evaporated light particles. The mirror symmetry of 59Zn and 59Cu is discussed.
Received: 28 May 2002 / Accepted: 10 July 2002 / Published online: 3 December 2002
RID="a"
ID="a"Present address: Oliver Lodge Laboratory, University of Liverpool, P.O. Box 147, Liverpool, L69 7ZE, United Kingdom; e-mail: ca@ns.ph.liv.ac.uk.
RID="b"
ID="b"Present address: Physik-Departament, Technische Universit?t München, D-85748 Garching, Germany.
Communicated by W. Henning 相似文献
117.
Part of this work was done while the second author was visiting the University of Georgia, Athens/Georgia, USA. 相似文献
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119.
(+)-Bis(methyl-1-naphthylphenylsilyl)mercury has been prepared, though probably in an optically impure state. Racemization without decomposition takes place at about 150°, and stereospecific cleavages of the Si—Hg bonds are possible. 相似文献
120.
Talat S. Rahman D.L. Mills J.E. Black 《Journal of Electron Spectroscopy and Related Phenomena》1983,29(1):199-212
Electron energy loss spectroscopy has proved a powerful probe of vibrational modes of a wide variety of adsorbed species. Here the primary focus has been on modes with frequency well above the maximum phonon frequency of the substrate. Examples are internal vibration modes of adsorbed molecules, possibly shifted significantly in frequency from their gas phase analogues, and high frequency vibrations of an adsorbed molecule or atom against the substrate. Recent experiments explore features in the energy loss spectrum with frequency below the maximum phonon frequency of the substrate, for ordered overlayers of atoms adsorbed on low index metal surfaces. We shall summarize our theoretical studies of such spectra for several adsorbate/substrate combinations, with emphasis oh the physical origin of the features which appear in the calculations. We obtain a good account of the existing data, within the framework of a rather simple lattice dynamical model, and the calculations show that the features which appear are quite sensitive to the symmetry of the adsorption sits, and other details of the surface geometry. We shall illustrate this with several specific examples. 相似文献