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81.
Applied Intelligence - Object detection and tracking is one of the most important and challenging branches in computer vision, and have been widely applied in various fields, such as health-care... 相似文献
82.
J. A. Saggio K. Sujata J. Hahn S. J. Hwu K. R. Poeppelmeier T. O. Mason 《Journal of the American Ceramic Society》1989,72(5):849-853
Solid-phase relationships have been determined for the Bi2 O3 –SrO–CuO system at 800°C in air with and without Li2 CO3 mineralizer. Two ternary compounds were detected with Bi:Sr:Cu ratios of approximately 2:2:1 and a solid-solution phase 11−;x:9+x:5 with 0x0.4. The solid-solution phase is a 9 K super-conductor at x=0.4. Two additional compounds with Bi:Sr:Cu ratios of approximately 4:9:1 and 2:7:2 are apparently stabilized by the presence of Li2 CO3 , but do not form without it. X-ray crystallographic data are provided for each compound. Ramifications for quaternary Bi:Sr:Ca:Cu-O superconductors are discussed. 相似文献
83.
Summary: Ethylene vinyl acetate (EVA) copolymer/dodecyl ammonium ion intercalated montmorillonite (12Me‐MMT) nanocomposites were swelled in xylene under atmospheric condition. Swelling index of these nanocomposites decreased with filler loading indicating that the solvent uptake of these nanocomposites was inversely related to the filler contents. The volume fractions of nanocomposites showed an increasing trend with filler concentration because of unswelling effect exerted by aluminosilicate layers. The cross‐link density was determined using the Flory‐Rehner equation and it was observed that the cross‐link density of these nanocomposites also showed an increasing trend with increasing filler loading. Free energy change (ΔGmix) and the change in entropy (ΔSmix) on swelling of EVA/12Me‐MMT nanocomposites in xylene were calculated and these values reaffirmed that the interaction between polymer chains and silicate layers was very strong which induced remarkable inhibiting ability on EVA matrix when swelled in xylene.
84.
85.
Smith L. Moroz V. Eneman G. Verheyen P. Nouri F. Washington L. Jurczak M. Penzin O. Pramanik D. De Meyer K. 《Electron Device Letters, IEEE》2005,26(9):652-654
Hole mobility is found to more than double in fabricated p-MOSFETs with SiGe source/drain due to longitudinal compressive stress in the channel exceeding 1 GPa. The maximum observed low-field mobility enhancement is 140% at a simulated stress level of 1.45 GPa. The mobility enhancement is approximately linear with stress at moderate levels but becomes super-linear above 1 GPa. An important consequence of this behavior is that for moderate stress levels, an average channel stress can be used to estimate the performance of transistors with a nonuniform stress distribution across the channel width. Two alternative approaches to model stress-enhanced hole mobility are suggested. Analysis of the physical effects behind the experimental observations reveals the relative roles of band repopulation and mass modulation. In addition, previously published wafer bending experiments with compressive stress levels below 400 MPa are used to implicitly verify the accuracy of the stress simulations. 相似文献
86.
Sujata Kumari Sayanika Banerjee Manoj Kumar Arata Hayashi Balakrishnan Solaimuthu Einav Cohen-Kfir Yoav D. Shaul Alexander Rouvinski Reuven Wiener 《International journal of molecular sciences》2022,23(13)
Ufmylation is a posttranslational modification in which the modifier UFM1 is attached to target proteins. This conjugation requires the concerted work of three enzymes named UBA5, UFC1, and UFL1. Initially, UBA5 activates UFM1 in a process that ends with UFM1 attached to UBA5’s active site Cys. Then, in a trans-thiolation reaction, UFM1 is transferred from UBA5 to UFC1, forming a thioester bond with the latter. Finally, with the help of UFL1, UFM1 is transferred to the final destination—a lysine residue on a target protein. Therefore, not surprisingly, deletion of one of these enzymes abrogates the conjugation process. However, how overexpression of these enzymes affects this process is not yet clear. Here we found, unexpectedly, that overexpression of UBA5, but not UFC1, damages the ability of cells to migrate, in a similar way to cells lacking UBA5 or UFC1. At the mechanistic level, we found that overexpression of UBA5 reverses the trans-thiolation reaction, thereby leading to a back transfer of UFM1 from UFC1 to UBA5. This, as seen in cells lacking UBA5, reduces the level of charged UFC1 and therefore harms the conjugation process. In contrast, co-expression of UBA5 with UFM1 abolishes this effect, suggesting that the reverse transfer of UFM1 from UFC1 to UBA5 depends on the level of free UFM1. Overall, our results propose that the cellular expression level of the UFM1 conjugation enzymes has to be tightly regulated to ensure the proper directionality of UFM1 transfer. 相似文献
87.
New chemical methods for the deposition of thin film of Cu1·8S and TlSe have been developed. The deposition of Cu1·8S thin film has been performed by thiourea, ammonia and Cu2+ ions at room temperature, while TlSe thin films are obtained from triethanolamine as complexing agent, ammonia, sodium selenosulphate
solution and Tl1+ ions at room temperature. The electrical resistance, mobility, carrier concentration and optical band gap have been measured. 相似文献
88.
Paknia A. Pramanik A. Dixit A. R. Chattopadhyaya S. 《Journal of Materials Engineering and Performance》2016,25(10):4444-4459
Journal of Materials Engineering and Performance - The objective of this research was to investigate the mechanical behavior of metal matrix composites (MMCs) 6061 aluminum, reinforced with silicon... 相似文献
89.
Ethanol is one of the promising future fuels of Direct Alcohol Fuel Cells (DAFC). The electro‐oxidation of ethanol fuel on anode made of carbon‐supported Pt‐Ru electrode catalysts was carried out in a lab scale direct ethanol fuel cell (DEFC). Cathode used was Pt‐black high surface area. The membrane electrode assembly (MEA) was prepared by sandwiching the solid polymer electrolyte membrane, prepared from Nafion® (SE‐5112, DuPont USA) dispersion, between the anode and cathode. The DEFC was fabricated using the MEA and tested at different catalyst loadings at the electrodes, temperatures and ethanol concentrations. The maximum power density of DEFC for optimized value of ethanol concentration, catalyst loading and temperature were determined. The maximum open circuit voltage (OCV) of 0.815 V, short circuit current density (SCCD) of 27.90 mA/cm2 and power density of 10.30 mW/cm2 were obtained for anode (Pt‐Ru/C) and cathode (Pt‐black) loading of 1 mg/cm2 at a temperature of 90°C anode and 60°C cathode for 2M ethanol. 相似文献
90.
The grafting of N,N′‐methylenebisacrylamide (N,N′‐MBA) onto cellulose is carried out using the cobaltacetylacetonate complex (Co(acac)3) under nitrogen atmosphere at 40°C. The rate of graft copolymerization has been studied as a function of [N,N′‐MBA], [Co(acac)3], and temperature. The activation energy of grafting is found to be 156.0 k J mol−1 within the temperature range of 30–60°C. The effect of perchloric acid, methanol, and surfactants on graft yield has also been studied and results are suitably explained. The higher efficiency of the metal chelate in initiation of graft copolymerization has been assumed due to the coordination of the π electrons of the N,N′‐MBA with the metal chelate, which facilitated the formation of the radicals through homolytic cleavage of metal–oxygen bond of the cobalt acetylacetonate complex. On the basis of the results, a suitable kinetic scheme for graft copolymerization is presented and rate expression is derived. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 906–912, 2000 相似文献