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排序方式: 共有3419条查询结果,搜索用时 13 毫秒
991.
992.
An infrared thickness measuring technique for thin film coated on the metal mold was developed and applied to thickness measuring of the artificial breast implant pack. The infrared light emitted from a metal mold itself was partly absorbed to the silicon film, and the remainder of the infrared light was transmitted through the film. The relationship between the thermal image captured by an infrared camera and the film thickness was analyzed. The thicker the film, the bigger the amount absorbed. The new infrared thickness measuring technique agreed well with the results directly measured by a microscope when applied to the artificial breast implant pack. 相似文献
993.
Sung-Nam Lee Ryu H.Y. Paek H.S. Son J.K. Sung Y.J. Kim K.S. Kim H.K. Kim H. Jang T. Ha K.H. Nam O.H. Park Y. 《Electron Device Letters, IEEE》2008,29(8):870-872
InGaN quantum-well (QW) green laser diodes (LDs) with an emission wavelength of 483.7 nm were characterized by controlling the injection pulsewidth. The emission wavelength of LDs showed a large blueshift (> 20 nm) of spontaneous emission peak with increasing injection current below the threshold current. The huge blueshift was ascribed to the deep In localization states and the strong piezoelectric field in the green InGaN QW structure with higher In contents than conventional violet/blue InGaN QWs. However, the lasing wavelength of LDs was slightly redshifted by increasing the injection pulsewidth due to the thermal heating effects. 相似文献
994.
A cooperative coding scheme using M-ary modulation for high spectral efficiency and repetitive information transmission for diversity improvement is proposed.
The encoder is a parallel concatenation of two bit-interleaved coded M-ary modulators (BICM) with scalable repetition of information symbols. As a result, the fraction of repeated information
and the spectral efficiency of M-ary modulation can be used for bandwidth-performance tradeoff. Performance analysis is carried out to verify the performance
advantage of the proposed system. In particular, analytical and simulation results in various block fading scenarios show
that for a given bandwidth efficiency, a proper selection of the fraction of repeated information and the spectral efficiency
of M-ary modulation can provide a large performance improvement.
相似文献
Ha H. NguyenEmail: |
995.
Sang Eun Ha Seong Min Kim Preethi Vetrivel Hun Hwan Kim Pritam Bhagwan Bhosale Jeong Doo Heo Ho Jeong Lee Gon Sup Kim 《International journal of molecular sciences》2021,22(16)
Scutellarein (SCU) is a well-known flavone with a broad range of biological activities against several cancers. Human hepatocellular carcinoma (HCC) is major cancer type due to its poor prognosis even after treatment with chemotherapeutic drugs, which causes a variety of side effects in patients. Therefore, efforts have been made to develop effective biomarkers in the treatment of HCC in order to improve therapeutic outcomes using natural based agents. The current study used SCU as a treatment approach against HCC using the HepG2 cell line. Based on the cell viability assessment up to a 200 μM concentration of SCU, three low-toxic concentrations of (25, 50, and 100) μM were adopted for further investigation. SCU induced cell cycle arrest at the G2/M phase and inhibited cell migration and proliferation in HepG2 cells in a dose-dependent manner. Furthermore, increased PTEN expression by SCU led to the subsequent downregulation of PI3K/Akt/NF-κB signaling pathway related proteins. In addition, SCU regulated the metastasis with EMT and migration-related proteins in HepG2 cells. In summary, SCU inhibits cell proliferation and metastasis in HepG2 cells through PI3K/Akt/NF-κB signaling by upregulation of PTEN, suggesting that SCU might be used as a potential agent for HCC therapy. 相似文献
996.
Ha Seulki Park Sangheon Lim Hyeoncheol Baek Seung Ho Kim Do Kyoung Yoon Sang-Hee 《Journal of Mechanical Science and Technology》2019,33(7):3237-3244
Journal of Mechanical Science and Technology - Advancement in wearable healthcare technology allows a digital revolution in healthcare that is intended to extend life length and improve life... 相似文献
997.
998.
Transmission electron microscopy images showed that ZnO nanoparticles were randomly distributed inside the polymethyl methacrylate (PMMA) layer. Capacitance-voltage (C-V) measurements on the Al/ZnO nanoparticles embedded in a PMMA layer/C60/p-Si diode at 300 K showed a clockwise hysteresis with a flatband voltage shift due to existence of the ZnO nanoparticles and a C60 buffer layer. The insertion of the C60 layer enlarged the memory window of the device containing the ZnO nanoparticle, as estimated by the flatband voltage shift in the C-V hysteresis. Capacitance-time measurements showed that the devices exhibited excellent memory retention ability at ambient conditions. Operating mechanisms of the charge injection, capture, and emission in the active layer and the charging and the discharging processes in the devices are described on the basis of the C-V results. 相似文献
999.
Jeon SM Yoo SI Kim KS Kim DH Sohn BH 《Journal of nanoscience and nanotechnology》2010,10(10):6819-6824
We controlled the fluorescence resonance energy transfer (FRET) between ZnO nanoparticles and rhodamine B (RB) within multilayered thin films prepared by the layer-by-layer (LbL) assembling method. Positively charged ZnO nanoparticles and RB-labeled poly(allyamine hydrochloride) (RB-PAH) were accurately incorporated into LbL assemblies of polyelectrolytes. The distance between ZnO nanoparticles and RB-PAH was adjusted by varying the number of layers of pure polyelectrolytes, leading to the controlled FRET from ZnO nanoparticles to RB-PAH. 相似文献
1000.
This paper suggests a novel method for improving the ductility of magnesium alloy sheets using a laser scanning treatment combined with a defocusing technique. The crystallographic orientation on both surface regions of the AZ31B magnesium alloy sheet processed using this method was changed from a strong basal texture to an almost random texture. The laser-scanned magnesium alloy sheet showed enhanced tensile elongation of up to 50% with a similar a tensile strength. 相似文献