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排序方式: 共有3239条查询结果,搜索用时 15 毫秒
71.
Do Il Chang Dong Sung Lim Min Yong Jeon Hak Kyu Lee Kyong Hon Kim Taesang Park 《Electronics letters》2000,36(16):1356-1358
Dual-wavelength lasing at 1480 and 1500 nm has been demonstrated from a cascaded Raman fibre laser with a WDM coupler and two pairs of Bragg gratings. Intensity-adjustable, wavelength-tunable laser operation was achieved by tensile stress wavelength tuning of the gratings 相似文献
72.
Moumita Mukherjee Biswanath Mukherjee Youngill Choi Kyoseung Sim Junghwan Do Seungmoon Pyo 《Synthetic Metals》2010,160(5-6):504-509
We report a copper hexadecafluorophthalocyanine (F16CuPc) based n-type organic field-effect transistor (OFET) with polymeric gate dielectrics with different physical/electrical properties. The gate dielectrics are four types of cross-linked poly(4-vinylphenol) and newly prepared poly(4-phenoxy methyl styrene) and those are characterized based on surface tension, leakage current and capacitance. The performance of F16CuPc OFETs with those gate dielectrics was compared. We found that the composition of the gate dielectrics and the interfacial interaction of F16CuPc with the gate dielectric play a decisive role in the performance of OFETs. The effect of physical/electrical properties, composition and processing condition of the gate dielectrics on the device performance was investigated. 相似文献
73.
Kee Do Woo Jae Hwang Kim Eui Pyo Kwon Min Seok Moon Hyun Bom Lee Tatsuo Sato Zhiguang Liu 《Metals and Materials International》2010,16(2):213-218
To fabricate an Al-V matrix composite reinforced with submicron-sized Al2O3 and AlxVy (Al3V, Al10V) phases, high energy mechanical milling (HEMM) and sintering were employed. By increasing the milling time, the size of mechanically milled powder was significantly reduced. In this study, the average powder size of 59 μm for Al, and 178 μm for V2O5 decreased with the formation of a new product, Al-Al2O3-AlxVy, with a size range from 1.3 μm to 2.6 μm formed by the in-situ combustion reaction during sintering of HEM milled Al and V2O5 composite powders. The in-situ reaction between Al and V2O5 during the HEMM and sintering transformed the Al2O3 and AlxVy (Al3V, Al10V) phases. Most of the reduced V reacted with excess the Al to form AlxVy (Al3V, Al10V) with very little V dissolved into Al matrix. By increasing the milling time and weight percentage of V2O5, the hardness of the Al-Al2O3-AlxVy composite sintered at 1173 K increased. The composite fabricated with the HEMM Al-20wt.%V2O5 composite powder and sintering at 1173 K for 2 h had the highest hardness. 相似文献
74.
75.
Polyaniline nanocomposites encapsulating gold nanoparticles on camphor sulfonic acid (CSA) surface were prepared via the polymerization of aniline hydrochloride with different concentrations of CSA using HAuCl4 as oxidant. The synthesized composites were characterized by Fourier transform infrared spectroscopy and UV–visible spectroscopy. Surface morphology was studied by scanning electron microscopy and transmission electron microscopy. The embedded crystallinity of the composites was investigated by X‐ray diffraction analysis. The solubility of the nanocomposites was studied using water, N‐methyl‐2‐pyrrolidinone, chloroform, and dimethylformamide solvents. The room temperature direct current conductivity of the composites was also observed in solution state. Electrical property of the composites was examined using cyclic voltammetric measurements at room temperature. The fabricated polymer nanocomposites with better solubility in water and some organic solvents will have various applications in electrical devices and biosensors. POLYM. COMPOS., 36:245–252, 2015. © 2014 Society of Plastics Engineers 相似文献
76.
Kyung Rae Ko Hyunil Lee Soo-Hong Han Wooyeol Ahn Do Kyung Kim Il-Su Kim Bo Sung Jung Soonchul Lee 《International journal of molecular sciences》2022,23(5)
A large number of studies have focused on the role of substance P (SP) and the neurokinin-1 receptor (NK1R) in the pathogenesis of a variety of medical conditions. This review provides an overview of the role of the SP-NK1R pathway in the pathogenesis of musculoskeletal disorders and the evidence for its role as a therapeutic target for these disorders, which are major public health problems in most countries. To summarize, the brief involvement of SP may affect tendon healing in an acute injury setting. SP combined with an adequate conjugate can be a regenerative therapeutic option in osteoarthritis. The NK1R antagonist is a promising agent for tendinopathy, rheumatoid arthritis, and osteoarthritis. Research on the SP-NK1R pathway will be helpful for developing novel drugs for osteoporosis. 相似文献
77.
Vo Phuoc-Hung Nguyen Thai-Son Huynh Van-Thanh Do Thanh-Nghi 《Multimedia Tools and Applications》2018,77(21):28777-28797
Multimedia Tools and Applications - In this paper, we propose a novel reversible data hiding technique based on two-dimensional histogram shifting for quantized discrete cosine transformation... 相似文献
78.
Effects of operating parameters in the thermal gradient chemical vapor infiltration of propane such as thermal gradient, diffusion, infiltrations time, and concentration of propane were studied by focusing on the visualizations of the intrinsic effects of these parameters. A uniform deposition in the preform was obtained with a gradually increasing temperature along the gas flow. The uniformity of deposition through the preform got improved with increasing deposition time. Results of numerical modeling estimated the experimental data very well when the pre-exponential factor of the overall rate of carbon deposition from propane reported by Vaidyaraman[1] was multiplied by 4. The average density of a preform increased by about 3 times from 0.38 to 1.15 g/cm3 after 60 hr deposition with a thermal gradient under the conditions of 3% propane in nitrogen and 840 to 900 ℃. 相似文献
79.
Kilicaslan M. Fatih Altaib Salaheddin Salem Vurdu Can Doğan 《Metals and Materials International》2019,25(6):1457-1466
Metals and Materials International - In this project the morphology and microstructure of both conventional cast and melt spun of Al–20Si–9Fe–1.2Nb and... 相似文献
80.