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101.
Jongwon Yoon Woojin Park Ga‐Yeong Bae Yonghun Kim Hun Soo Jang Yujun Hyun Sung Kwan Lim Yung Ho Kahng Woong‐Ki Hong Byoung Hun Lee Heung Cho Ko 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(19):3295-3300
A highly flexible and transparent transistor is developed based on an exfoliated MoS2 channel and CVD‐grown graphene source/drain electrodes. Introducing the 2D nanomaterials provides a high mechanical flexibility, optical transmittance (~74%), and current on/off ratio (>104) with an average field effect mobility of ~4.7 cm2 V?1 s?1, all of which cannot be achieved by other transistors consisting of a MoS2 active channel/metal electrodes or graphene channel/graphene electrodes. In particular, a low Schottky barrier (~22 meV) forms at the MoS2/graphene interface, which is comparable to the MoS2/metal interface. The high stability in electronic performance of the devices upon bending up to ±2.2 mm in compressive and tensile modes, and the ability to recover electrical properties after degradation upon annealing, reveal the efficacy of using 2D materials for creating highly flexible and transparent devices. 相似文献
102.
Yang Y Hwang Y Cho HA Song JH Park SJ Rogers JA Ko HC 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(4):484-491
The ability to create and manipulate large arrays of inorganic semiconductor micro/nanostructures for integration on unconventional substrates provides new possibilities in device engineering. Here, simple methods are described for the preparation of structures of single crystalline silicon in suspended and tethered configurations that facilitate their deterministic assembly using transfer-printing techniques. Diverse shapes (e.g., straight or curved edges), thicknesses (between 55 nm and 3 μm), and sizes (areas of 4000 μm(2) to 117 mm(2) ) of structures in varied layouts (regular or irregular arrays, with dense or sparse coverages) can be achieved, using either flat or cylindrical roller-type stamps. To demonstrate the technique, printing with 100% yield onto curved, rigid supports of glass and ceramics and onto thin sheets of plastic is shown. The fabrication of a printed array of silicon p(+) -i-n(+) junction photodiodes on plastic is representative of device-printing capabilities. 相似文献
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105.
Yi Hayoon Cho Yeongpil Paek Yunheung Ko Kwangman 《The Journal of supercomputing》2019,75(8):4575-4600
The Journal of Supercomputing - In computer systems, ensuring the integrity of the kernel assumes importance as attacks against the kernel allow an adversary to obtain the highest privilege within... 相似文献
106.
107.
SH Ahn DW Seo YK Ko DS Sung GU Bae JW Yoon SY Hong JW Han HW Lee 《Canadian Metallurgical Quarterly》1998,21(6):657-663
OBJECTIVE: To identify factors associated with the initiation of breast-feeding in a predominantly Puerto Rican population living in inner-city Hartford, Conn. DESIGN: Retrospective study of 144 Latino women (mean +/- standard deviation age = 26.3 +/- 5.7 years) with children at least 1 year old but younger than 6 years old (mean +/- standard deviation age = 3.0 +/- 1.2 years) at the time of the survey. Women were recruited from agencies sponsoring health programs for mothers and children. They were interviewed in their homes (69%) or at the Hispanic Health Council, Hartford, Conn (31%). SUBJECTS/SETTING: Low-income Latino women who had at least 1 preschooler at the time of the interview. The women lived in inner-city Hartford, and the overwhelming majority were Puerto Rican and received welfare assistance and food stamps. Seventy-eight percent of the women chose to be interviewed in Spanish; the other 22% were interviewed in English. STATISTICAL ANALYSES: Explanatory variables that related to breast-feeding initiation (P < or = .2) in bivariate chi 2 analyses were entered into a multivariate logistic regression model that was reduced using backward stepwise elimination procedures. RESULTS: Multivariate analyses indicated that breast-feeding the previous child, shorter length of maternal residence in the United States, not receiving prenatal bottle-feeding advice, more recent birth, and higher birth weight were positively associated with breast-feeding initiation. A major reason for choosing not to breast-feed was that women felt socially uncomfortable doing it. APPLICATIONS: Breast-feeding initiation was more likely in Latino women who received prenatal breast-feeding counselling and postpartum support. Mothers of low-birth-weight infants and women breast-feeding for the first time may need additional help. These findings can be used by programs like the Special Supplemental Nutrition Program for Women, Infants, and Children to increase breast-feeding initiation. 相似文献
108.
Tribological behavior of hydrogenated diamond-like carbon (DLC) films and Si incorporated DLC (Si-DLC) films deposited on Si (100) wafer by r.f.-plasma assisted chemical vapor deposition were investigated by ball-on-disk type tribometry in various environments. The friction tests were performed in ambient air of relative humidity ranging from 0% to 90% or dry oxygen environment. We focused on the tribochemical reactions by analyzing chemical composition, chemical bond structure and agglomerated shape of the debris. High and unstable friction behavior was observed in both humid air and dry oxygen environments. In these environments, Auger spectrum analysis showed that the debris contained large amounts of Fe. Significant incorporation of Fe in the debris resulted from the wear of the steel ball, which might be enhanced by the surface oxidation of the ball. These results show that the humidity dependence of friction coefficient is not an inherent tribological property of DLC films but results from the surface reaction of the steel ball in humid environments. Two possible reasons for the Fe rich debris affecting the friction behavior are presented. Reduced dependence of the friction coefficient on the relative humidity observed for Si-DLC films is discussed in terms of the two possible reasons. 相似文献
109.
Derya Koçak Hasene Keskin Sibel Fadıloğlu Boleslaw Kowalski Fahrettin Göğüş 《Journal of the American Oil Chemists' Society》2011,88(10):1531-1538
Characterization of the fatty acid and triacylglycerol composition of terebinth fruit oil and the synthesis of structured
lipids (SL) were performed in this study. Interesterification reaction of terebinth fruits oil (Pistacia terebinthus L.) with caprylic acid (CA) and stearic acid (SA) to produce a SL was performed in n-hexane using immobilized sn-1,3 specific lipase from Mucor miehei. The effect of reaction conditions and relationship among them were analyzed by response surface methodology (RSM) with a
four-factors five-level central composite rotatable experimental design. The four major factors chosen were enzyme load (10–30 wt%
based on substrates), reaction time (7–18 h), reaction temperature (40–60 °C) and substrate mole ratio (terebinth oil:SA:CA
1:1:1–1:1:3). The best fitting quadratic model was determined by regression and backward elimination. Based on the fitted
model, the optimal reaction conditions for the incorporation of CA and SA were found to be temperature 50 °C; time 18 h; enzyme
load 30 wt%; substrate ratio 1:1:3. Under these optimum conditions, the incorporation of SA and CA could be obtained as 19
and 14%, respectively. 相似文献
110.
Suk‐Joong L. Kang Ji‐Hoon Park Seok‐Young Ko Ho‐Yong Lee 《Journal of the American Ceramic Society》2015,98(2):347-360
Solid‐state conversion of single crystals from polycrystalline materials has the advantages of cost‐effectiveness, chemical homogeneity, and versatility over the conventional melt growth and solution growth methods, particularly for systems with high melting points, incongruent melting, high reactivity (volatility), and phase transformations at high temperature. Nevertheless, for commercial production, this technique has only been successful in a few limited systems, in particular ferroelectric systems. This is mostly because of the difficulty in controlling the microstructure, particularly suppressing grain growth in the polycrystal during its conversion. This article describes the principle and the current status of the solid‐state conversion of single crystals. We first introduce the recently developed principle of microstructural evolution to explain the basis of the microstructure control in polycrystals for solid‐state conversion. We then report recent technical developments in fabricating single crystals by the solid‐state single crystal growth (SSCG) method and their physical properties. The SSCG method is expected to be studied and utilized more widely in fabricating single crystals with complex compositions as a strong alternative to the melt growth and solution growth methods. 相似文献