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331.
Sivapalan BaskaranNarayanan Ramachandran Xiangtong HeSankar Thiruvannamalai Ho Joon LeeHyun Heo Qin ChenJohn Y. Fu 《Physics letters. A》2011,375(20):2082-2084
Recent studies have shown that giant flexoelectricity may exist in certain elastomers with bent-core molecular structures, which contradicts the previous theoretical estimation that the flexoelectric coupling is small in those materials. In this Letter, we report an analogous phenomenon, i.e., the giant direct flexoelectric effect, observed in a polyvinylidene fluoride (PVDF) film. Our experimental studies indicate that such an enhanced flexoelectric effect might be induced by the interaction between the energy couplings of the apolar and the polar molecular structures of the polymer film under elastic deformation. 相似文献
332.
Based on the Hilbert C?-module structure we study non-stationary monotone quantum stochastic processes and general Markov processes constructed from quantum dynamical hemigroups indexed by a totally ordered set. We prove that the quantum stochastic monotone process implementing the weakly covariant process described by a covariant quantum dynamical hemigroup with respect to a symmetry semigroup is again covariant in the strong sense. 相似文献
333.
Heo JY Cho CH Jeon HS Cheong BS Cho HG 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,83(1):425-431
The surface-enhanced Raman spectrum of lawsone, a well known natural dye, has been investigated. Activation with KNO(3) or Na(2)SO(4) solution was necessary to enhance the Raman signal, whereas addition of NaCl solution depletes the effects. In the enhanced Raman spectrum, the strong double-bond stretching bands are most distinctive and show large red shifts from those in the infrared and FT-Raman spectra. The observed strong double-bond stretching bands reflect lawsone coordinated perpendicular to the Ag surface. DFT computations have been carried out for the plausible configurations of lawsone coordinated to an adatom on the Ag surface. Lawsone coordinated to an Ag(+) adatom with H(+) released best reproduces the observed vibrational characteristics. 相似文献
334.
Kiseok Jeon Seung Wook Shin Jaeseung Jo Myung Sang Kim Jae Cheol Shin Chaehwan Jeong Jun Hyung Lim Junho Song Jaeyeong Heo Jin Hyeok Kim 《Current Applied Physics》2014,14(11):1591-1595
High-energy electron-beam irradiation of indium gallium zinc oxide (IGZO) films improved the short-range arrangement. The increase in band gap was used as an indication of such improvement. X-ray diffraction confirmed that the films treated with a DC voltage of 2–4.5 kV for duration of up to 35 min are in the amorphous state or nanocrystalline phase. Higher energy electron-beam irradiation led to increased conductivity, which mainly comes from the drastic increase in electron concentration. Electron-beam treatment could be a viable route to improve the contact resistance between the source/drain and channel layer in thin-film transistor devices. 相似文献
335.
Keun Heo Kyung‐Sang Cho Jae Hyun Lee Yamujin Jang Sangsig Kim Sung Woo Hwang Dongmok Whang 《固体物理学:研究快报》2014,8(7):617-620
In this study, large area mono‐, bi‐, and multi‐layer graphenes (MLG) were synthesized using low pressure chemical vapor deposition (LPCVD) process and co‐planar waveguides (CPW) with graphenes being fabricated using conventional photolithography. The intrinsic room temperature radio frequency (RF) characteristics were measured via direct contact to the graphene surface with a probe–tip in the range of 0.1 GHz to 40 GHz without using metal electrodes. The device characteristics were also evaluated by physics‐based RLC equivalent circuit simulation. The proposed equivalent circuit model reproduced all of the measured characteristics within 3% of RMSE and we numerically extracted the set of component values which minimize the error between the measured data and the simulation results over the measured regime. Our findings demonstrate that MLG is an effective candidate in RF interconnect device applications. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
336.
Eun Jeong Heo 《International Journal of Game Theory》2014,43(2):439-454
We study the problem of assigning objects to a set of agents. We focus on probabilistic solutions that only take agents’ preferences over objects as input. Importantly, agents may be indifferent among several objects. The “extended serial correspondence” is proposed by Katta and Sethuraman (J Econ Theory 131:231–250, 2006) to solve this problem. As a follow-up to Liu and Pycia (Ordinal efficiency, fairness, and incentives in large markets. Mimeo, 2012) who introduce the notion of profiles with “full support”, we work with two interesting classes of preference profiles: profiles that (i) have rich support on a partition or (ii) are single-peaked with rich support on a partition. For each profile in these classes, an assignment matrix is selected by the extended serial correspondence if and only if it is sd-efficient and sd envy-free. We also provide an asymptotic result. 相似文献
337.
In-Sung Song Yu Jeong Jeong Seung Hun Jeong Hye Jin Heo Hyoung Kyu Kim Sung Ryul Lee Tae Hee Ko Jae Boum Youm Nari Kim Kyung Soo Ko Byoung Doo Rhee Jin Han 《Experimental & molecular medicine》2013,45(10):e50
Bortezomib is a proteasome inhibitor used for the treatment of relapsed/refractory multiple myeloma (MM). However, intrinsic and acquired resistance to bortezomib has already been observed in MM patients. In a previous report, we demonstrated that changes in the expression of mitochondrial genes lead to changes in mitochondrial activity and bortezomib susceptibility or resistance, and their combined effects contribute to the differential sensitivity or resistance of MM cells to bortezomib. Here we report that the combination treatment of bortezomib and 2-methoxyestradiol (2ME), a natural estrogen metabolite, induces mitochondria-mediated apoptotic cell death of bortezomib-resistant MM KMS20 cells via mitochondrial reactive oxygen species (ROS) overproduction. Bortezomib plus 2ME treatment induces a higher level of cell death compared with treatment with bortezomib alone and increases mitochondrial ROS and Ca2+ levels in KMS20 cells. Pretreatment with the antioxidant N-acetyl-L-cysteine scavenges mitochondrial ROS and decreases cell death after treatment with bortezomib plus 2ME in KMS20 cells. Moreover, we observed that treatment with bortezomib plus 2ME maintains the activation of c-Jun N-terminal kinase (JNK) and mitogen-activated protein kinase kinase kinase 4/7 (MKK4/7). Collectively, combination treatment with bortezomib and 2ME induces cell death via JNK-MKK4/7 activation by overproduction of mitochondrial ROS. Therefore, combination therapy with specific mitochondrial-targeting drugs may prove useful to the development of novel strategies for the treatment of bortezomib-resistant MM patients. 相似文献
338.
Dr. Sang Soo Han Dr. Dong Hyun Jung Dr. Seung‐Hoon Choi Prof. Jiyoung Heo 《Chemphyschem》2013,14(12):2698-2703
We have used grand canonical Monte Carlo simulations with a first‐principles‐based force field to show that metal–organic frameworks (MOFs) with Li functional groups (i.e. C? Li bonds) allow for exceptional H2 uptake at ambient temperature. For example, at 298 K and 100 bar, IRMOF‐1‐4Li shows a total H2 uptake of 5.54 wt % and MOF‐200‐27Li exhibits a total H2 uptake of 10.30 wt %, which are much higher than the corresponding values with pristine MOFs. Li‐functionalized MOF‐200 (MOF‐200‐27Li) shows 11.84 wt % H2 binding at 243 K and 100 bar. These hydrogen‐storage capacities exceed the 2015 DOE target of 5.5 wt % H2. Moreover, the incorporation of Li functional groups into MOFs provides more benefits, such as higher delivery amount, for H2 uptake than previously reported Li‐doped MOFs. 相似文献
339.
An appended sector of two octet-colored scalars, each an electroweak doublet, is an interesting extension of the simple two Higgs doublet model motivated by the minimal flavor violation. Their rich CP violating interaction gives rise to a sizable electron electric dipole moment, besides the quark electric dipole moment via the two-loop contribution of Barr–Zee mechanism. 相似文献
340.
We obtain Calderón–Zygmund-type gradient estimates below the duality exponent of very weak solutions to p-Laplacian-type elliptic equations with non-divergence datum by providing an analytic approach without using the fractional maximal function of order 1 for the non-divergence datum. 相似文献