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91.
Electrocatalysts: Guided Evolution of Bulk Metallic Glass Nanostructures: A Platform for Designing 3D Electrocatalytic Surfaces (Adv. Mater. 10/2016) 下载免费PDF全文
Gustavo Doubek Ryan C. Sekol Jinyang Li Won‐Hee Ryu Forrest S. Gittleson Siamak Nejati Eric Moy Candy Reid Marcelo Carmo Marcelo Linardi Punnathat Bordeenithikasem Emily Kinser Yanhui Liu Xiao Tong Chinedum O. Osuji Jan Schroers Sundeep Mukherjee André D. Taylor 《Advanced materials (Deerfield Beach, Fla.)》2016,28(10):1902-1902
92.
Reproducible Enhancement of Fluorescence by Bimetal Mediated Surface Plasmon Coupled Emission for Highly Sensitive Quantitative Diagnosis of Double‐Stranded DNA 下载免费PDF全文
Nhu Hoa Thi Tran Kieu The Loan Trinh Jun‐Ho Lee Won Jung Yoon Heongkyu Ju 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(32)
Plasmonic enhancement of fluorescence from SYBR Green I conjugated with a double‐stranded DNA (dsDNA) amplicon is demonstrated on polymerase chain reaction (PCR) products. Theoretical computation leads to use of the bimetallic (Au 2 nm–Ag 50 nm) surface plasmons due to larger local fields (higher quality factors) than monometallic (Ag or Au) ones at both dye excitation and emission wavelengths simultaneously, optimizing fluorescence enhancement with surface plasmon coupled emission (SPCE). Two kinds of reverse Kretschmann configurations are used, which favor, in signal‐to‐noise ratio, a fluorescence assay that uses optically dense buffer such as blood plasma. The fluorescence enhancement (12.9 fold at maximum) with remarkably high reproducibility (coefficient of variation (CV) < 1%) is experimentally demonstrated. This facilitates credible quantitation of enhanced fluorescence, however unlikely to obtain by localized surface plasmons. The plasmon‐induced optical gain of 46 dB due to SPCE‐active dye molecules is also estimated. The fluorescence enhancement technologies with PCR enables LOD of the dsDNA template concentration of ≈400 fg µL?1 (CV < 1%), the lowest ever reported in DNA fluorescence assay to date. SPCE also reduces photobleaching significantly. These technologies can be extended for a highly reproducible and sufficiently sensitive fluorescence assay with small volumes of analytes in multiplexed diagnostics. 相似文献
93.
94.
The use a stabilized lithium structure as cathode material for batteries could be a fundamental alternative in the development of next-generation energy storage devices. However, the lithium structure severely limits battery life causes safety concerns due to the growth of lithium (Li) dendrites during rapid charge/discharge cycles. Solid electrolytes, which are used in high-density energy storage devices and avoid the instability of liquid electrolytes, can be a promising alternative for next-generation batteries. Nevertheless, poor lithium ion conductivity and structural defects at room temperature have been pointed out as limitations. In this study, through the application of a low-dimensional graphene quantum dot (GQD) layer structure, stable operation characteristics were demonstrated based on Li+ ion conductivity and excellent electrochemical performance. Moreover, the device based on the modified graphene quantum dots (GQDs) in solid state exhibited retention properties of 95.3% for 100 cycles at 0.5 C and room temperature (RT). Transmission electron microscopy analysis was performed to elucidate the Li+ ion action mechanism in the modified GQD/electrolyte heterostructure. The low-dimensional structure of the GQD-based solid electrolyte has provided an important strategy for stably-scalable solid-state lithium battery applications at room temperature. It was demonstrated that lithiated graphene quantum dots (Li-GQDs) inhibit the growth of Li dendrites by regulating the modified Li+ ion flux during charge/discharge cycling at current densities of 2.2–5.5 mA cm, acting as a modified Li diffusion heterointerface. A full Li GQD-based device was fabricated to demonstrate the practicality of the modified Li structure using the Li–GQD hetero-interface. This study indicates that the low-dimensional carbon structure in Li–GQDs can be an effective approach for stabilization of solid-state Li matrix architecture. 相似文献
95.
Duplex spinel-ZrO2 ceramic composites were produced by an emulsion-hot kerosene drying technique. The sintered duplex spinel-ZrO2 ceramics which had the composition of 55 wt% Al2O3-20 wt% ZrO2-25 wt% MgO, consisted of a spinel matrix, whose grain size was in the range of 1.5 to 2.0 m, and uniformly dispersed zirconia agglomerates having grain sizes ranging from 1.0 to 2.0 m. Zirconia agglomerates began to appear at a temperature of 1500 °C and the duplex spinel-ZrO2 structure was formed with the weight ratio of Al2O3/MgO being within 1.67 to 2.20 and the amount of ZrO2 addition being within 5 to 25 wt %. The relative density, fracture toughness, flexural strength, and critical temperature difference of the spinel-ZrO2 composite were 97.8%, 1.98 MPam0.5, 390 MPa, and 275 °C, respectively. 相似文献
96.
S. S. Cho B. S. Chun C. H. Won B. S. Lee H. K. Kim B. J. Song M. Ryu 《Advanced Performance Materials》1996,3(1):29-42
The Al-12Si-5Fe-3Cu-1Mg(wt%) alloy was rapidly solidified by centrifugal atomization. The microstructural characteristics of rapidly solidified powder and the microstructure changes with heat treatment were investigated in terms and related to powder size. The microstructures of the powder consisted of dendritic -Al, eutectic phase, Cu-rich phase, and needle-like intermetallic compounds. These phases were much finer than that of ingot cast structure and the size decreased with increasing cooling rate. The X-ray diffraction of the atomized powders revealed the presence of non-equilibrium 3-(AlFeSi) intermetallic phase. This phase appeared to transform to an equilibrium -(AlFeSi) phase by heating at temperatures above 470°C. The extruded rod which was hot extruded at 360°C with an extrusion ratio of 40:1 also revealed the presence of the -(AIFeSi) intermetallic phase. Using DSC, the exothermic peak due to precipitation from the supersaturated -Al matrix was observed in the range of 200–250°C during continuous heating of atomized powder, and the size of the peaks increased with decreasing powder size. 相似文献
97.
Sul Gee Park Ho Cheol Jeong Jeong Won Kim Dong-Hwan Hwang Sang Jeong Lee 《International Journal of Control, Automation and Systems》2011,9(2):276-284
This paper proposes a magnetic compass fault detection method for GPS/INS/Magnetic compass integrated navigation systems.
The fault is assumed to be caused by the hard iron and soft iron effect and modeled as an abrupt change in the magnetic compass
output. In order to detect the fault, a test statistic related with only azimuth error measurement is determined. When a fault
is detected, the GPS/INS/Magnetic compass integrated navigation system is changed into a GPS/INS integrated navigation system
mode. In order to show the validity of the proposed method, computer simulation and van testing are carried out. The simulation
and van test results show that the proposed navigation system gives more accurate outputs than the GPS/INS/Magnetic compass
without the proposed method. 相似文献
98.
Abstract— High‐efficiency and simple‐structured red‐emitting phosphorescent devices based on the hole‐injection layer of 4,4′,4″‐tris(2‐naphthylphenyl‐phenylamino)‐triphenylamine [2‐TNATA] and the emissive layer of bis(10‐hydroxybenzo[h] quinolinato)beryllium complex [Bebq2] doped with SFC‐411 (proprietary red phosphorescent dye) have been researched. The fabricated devices are divided into three types depending on whether or not the hole‐transport layer of N,N′‐bis(1 ‐naphthyl)‐N, N'‐diphenyl‐1,1′‐biphenyl‐4,4′‐diamine [NPB] or the electron‐transport layer of SFC‐137 (proprietary electron transporting material) is included. Among the experimental devices, the best electroluminescent characteristics were obtained for the device with an emission structure of 2‐TNATA/Bebq2:SFC‐411/SFC‐137. In this device, current density and luminance were found to be 200 mA/cm2 and 15,000 cd/m2 at an applied voltage of 7 V, respectively. Current efficiencies were 15 and 11.6 cd/A under a luminance of 500 and 5000 cd/m2. The peak wavelength in the electroluminescent spectral distribution and color coordinates on the Commission Internationale de I'Eclairage (CIE) chart were 628 nm and (0.67, 0.33), respectively. 相似文献
99.
Hyunjoo Kim Heon Y. Yeom Sooyong Kang Youjip Won 《Multimedia Tools and Applications》2010,50(2):313-333
In this work, we develop an efficient storage technique to support real-time streaming of layer encoded video in a single
hard disk. The size of a single hard disk drive will soon be able to hold multi-tera bytes and is going to handle relatively
larger number of files. We expect that disk layout in a single disk will be rather critical issue in determining the efficiency
of the storage system. We propose a novel storage technique, Inter-Object Layer Clustering for layer encoded video objects. In Inter-Object Layer Clustering, storage is partitioned into two regions: lower layer partition
and upper layer partition. Lower and upper layer partition harbor the lower layer and upper layer data blocks across all video
objects and cluster them together. We develop an elaborate performance model for this placement scheme. We examine the performance
of the proposed technique using analytical formulation as well as a physical experiment. We found that clustering the layers
across all objects brings 100% increase in the number of concurrent sessions compared to the case where file is stored in
temporal order when the clients’ access bandwidth is narrow. Inter-Object Layer Clustering shows 15% performance improvement
compared to the clustering of layers within the objects. 相似文献
100.
Here we present a method for selectively and efficiently immobilizing antibodies to enhance the detection performance of surface plasmon resonance immune-sensors (SPRIs) for diagnostic applications. To improve the performance of antibody arrays, protein G was used as antibody-selective linkage layer with aldehyde functionalized poly-(para-xylylene) film. To estimate the efficiency of antibody immobilization, immunoglobulin G (IgG) was measured using the anti-IgG immobilized SPRIs. To demonstrate the proof-of-concept validation, the signal detected from the IgG using parylene-H film was compared with that of a combination of parylene-H and protein G in SPRIs. The results showed that the detection of IgG on the immobilized anti-IgG layer using the combination of parylene-H and protein G has a larger change of signal than that of using parylene-H layer. These results also imply that the anti-IgG was densely and efficiently immobilized on the modified surface with the linkage layer in a combination with parylene-H and protein G. Therefore, we believe that this combinatorial approach could selectively immobilize the antibodies, and also be applied for detection and diagnosis of immune diseases in the field of many SPRIs applications. 相似文献