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91.
This paper presents the experimental characterization of the in-plane deformation field at any depth within a granular support medium (GSM) called Carbomer 940 using digital image correlation (DIC) and particle image velocimetry (PIV). A method was developed to produce a 2D plane of randomly shaped speckles within the GSM for DIC. Four different needle diameters and four different speeds were used as test specimens representative of those utilized for 3D printing of soft matter in the GSM. The results can be used to determine dimensional tolerances and assessing interactions between multiple injection needles and acceptable spacing. The displacements in the direction of needle motion (u) and transverse (v) were obtained. Subsequently, the magnitudes were determined as a function of distance from the needle path and time history. Results show that near the needle there is a region of yielded/fluidized material and away from the needle path the material acts like a viscoelastic solid. Permanent deformation decreases with increased distance from the path and recovery is enhanced by reversing back through the path. 相似文献
92.
V. P. Danko S. N. Diyanova A. G. Abazyan 《Journal of Applied Mechanics and Technical Physics》2018,59(4):673-678
Hydrodynamic regimes of heat and mass transfer apparatuses with a moving packing are considered. Relations defining the critical velocity, the loss of momentum in the working area, and the dynamic thickness of the layer of packing elements are obtained which are necessary for engineering calculations. 相似文献
93.
The problem of describing the behavior of a highly filled polymeric material under compression, which was preceded by preliminary compression and unloading, is considered. The peculiarity of the compression diagrams obtained in the experiment is the downward convexity of the curves of the stress modulus versus time. To solve this problem, a variant of the non-linear endochronic theory of aging viscoelastic materials with several aging and viscosity functions and a numerical-graphical method for identifying the properties of viscoelasticmaterials proposed by the authors earlier, suggesting comparison of the deformation diagrams of intact samples and those that received preliminary damage, are used. 相似文献
94.
Chen Zhao Zifeng Chen Wei Wang Peixun Xiong Benfang Li Mengjie Li Dr. Jixing Yang Prof. Yunhua Xu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(29):12090-12096
Organic cathode materials have attracted extensive attention because of their diverse structures, facile synthesis, and environmental friendliness. However, they often suffer from insufficient cycling stability caused by the dissolution problem, poor rate performance, and low voltages. An in situ electropolymerization method was developed to stabilize and enhance organic cathodes for lithium batteries. 4,4′,4′′-Tris(carbazol-9-yl)-triphenylamine (TCTA) was employed because carbazole groups can be polymerized under an electric field and they may serve as high-voltage redox-active centers. The electropolymerized TCTA electrodes demonstrated excellent electrochemical performance with a high discharge voltage of 3.95 V, ultrafast rate capability of 20 A g−1, and a long cycle life of 5000 cycles. Our findings provide a new strategy to address the dissolution issue and they explore the molecular design of organic electrode materials for use in rechargeable batteries. 相似文献
95.
Jin Chen Dr. Chun-Li Hu Xiao-Han Zhang Dr. Bing-Xuan Li Dr. Bing-Ping Yang Prof. Jiang-Gao Mao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5419-5422
The first alkali-metal vanadium iodate fluoride, CsVO2F(IO3), with a novel 3D anionic framework, has been rationally designed and hydrothermally synthesized. The 3D [VO2F(IO3)]− framework in CsVO2F(IO3) is built from 0D Λ-shaped cis-[VO3F(IO3)2]4− polyanions via corner-sharing of oxo anions and bridging of the iodate groups. CsVO2F(IO3) displays both a strong second-harmonic generation (SHG) 1.1 times as strong as KTiOPO4 (KTP) under 2.05 μm laser radiation and high laser-induced damage threshold (LIDT) of 107.9 MW cm−2. This work provides a new route to design SHG crystals with stable 3D anionic structures from low-dimensional structural building units. 相似文献
96.
97.
K. E. Prikhodko M. M. Dementyeva B. A. Gurovich D. A. Komarov L. V. Kutuzov 《Crystallography Reports》2018,63(2):241-244
The change in the free-electron density in ultrathin (5 nm) superconducting NbN films in the initial state and after irradiation by O+ ions to doses of (0.1–0.9) × 1017 cm–2 has been studied by electron energy-loss spectroscopy (EELS). The analysis has been performed on cross section samples prepared by the focused ion beam method, using plasmon oscillations with energies up to 50 eV. The radiation-induced replacement of nitrogen atoms with oxygen atoms in niobium nitride is found to change the electrical properties of the material, which leads to a decrease in the free-electron density with an increase in the irradiation dose. 相似文献
98.
A. P. Dudka 《Crystallography Reports》2018,63(2):172-177
An accurate structure analysis of a Ba3TaGa3Si2O14 single crystal from langasite family was performed using four X-ray diffraction data sets collected on a diffractometer equipped with a CCD area detector (sp. gr. P321, Z = 1, sinθ/λ ≤ 1.35 Å–1; at 295 K a = 8.516(1) Å, c = 5.1910(6) Å, R/wR = 0.58/0.56%, Δρmin/Δρmax =–0.73/0.42 e/Å3, 4414 independent reflections; at 106 K a = 8.5109(9) Å, c = 5.1861(9) Å, R/wR = 0.75/0.86%, Δρmin/Δρmax =–0.81/1.06 e/Å3, 4382 reflections). The distinguishing feature of the Ba3TaGa3Si2O14 structure is a strong disorder of the Ga atom at the 3f site. Structural transformations in the series of Сa3TaGa3Si2O14–Sr3TaGa3Si2O14–Ba3TaGa3Si2O14–Ba3TaFe3Si2O14 crystals were analyzed. 相似文献
99.
G. Kalkabay A. L. Kozlovskiy M. A. Ibragimova D. I. Shlimas M. V. Zdorovets D. B. Borgekov A. V. Tikhonov 《Crystallography Reports》2018,63(1):90-95
Nickel nanotubes have been synthesized by electrochemical deposition, and their reactivity in aggressive media has been investigated. Kinetic curves of the variation in the atomic ratio between Ni and O in the nanotube crystal structure as a function of the medium acidity are built. 相似文献
100.
We summarize the results of our recent work on Bäcklund transformations (BTs), particularly focusing on the relation between BTs and infinitesimal symmetries. We present a BT for an associated Degasperis–Procesi (aDP) equation and its superposition principle and investigate the solutions generated by applying this BT. Following our general methodology, we use the superposition principle of the BT to generate the infinitesimal symmetries of the aDP equation. 相似文献