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991.
Jiyeon Lee Dahye Im Yajie Liu Jing Fang Xibao Tian Minsu Kim Prof. Wen-Bin Zhang Prof. Jongcheol Seo 《Angewandte Chemie (International ed. in English)》2023,62(51):e202314980
A technique combining ion mobility spectrometry-mass spectrometry (IMS-MS) and supercharging electrospray ionization (ESI) has been demonstrated to differentiate protein chemical topology effectively. Incorporating as many charges as possible into proteins via supercharging ESI allows the protein chains to be largely unfolded and stretched, revealing their hidden chemical topology. Different chemical topologies result in differing geometrical sizes of the unfolded proteins due to constraints in torsional rotations in cyclic domains. By introducing new topological indices, such as the chain-length-normalized collision cross-section (CCS) and the maximum charge state (zM) in the extensively unfolded state, we were able to successfully differentiate various protein chemical topologies, including linear chains, ring-containing topologies (lasso, tadpole, multicyclics, etc.), and mechanically interlocked rings, like catenanes. 相似文献
992.
993.
C. Masoller F.M. Atay 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,62(1):119-126
A network of delay-coupled logistic maps exhibits two different synchronization regimes,
depending on the distribution of the coupling delay times. When the delays are homogeneous
throughout the network, the network synchronizes to a time-dependent state [F.M. Atay, J.
Jost, A. Wende, Phys. Rev. Lett. 92, 144101 (2004)], which may be periodic or
chaotic depending on the delay; when the delays are sufficiently heterogeneous, the
synchronization proceeds to a steady-state, which is unstable for the uncoupled map [C.
Masoller, A.C. Marti, Phys. Rev. Lett. 94, 134102 (2005)]. Here we
characterize the transition from time-dependent to steady-state synchronization as the
width of the delay distribution increases. We also compare the two transitions to
synchronization as the coupling strength increases. We use transition probabilities
calculated via symbolic analysis and ordinal patterns. We find that, as the coupling
strength increases, before the onset of steady-state synchronization the network splits
into two clusters which are in anti-phase relation with each other. On the other hand,
with increasing delay heterogeneity, no cluster formation is seen at the onset of
steady-state synchronization; however, a rather complex unsynchronized state is detected,
revealed by a diversity of transition probabilities in the network nodes. 相似文献
994.
Kang-Pil Kim Daeic Chang Sang Kyoo Lim Soo-Keun Lee Hong-Kun Lyu Dae-Kue Hwang 《Current Applied Physics》2011,11(6):1311-1314
In this study, UV photodetectors based on a network of aluminium-doped zinc oxide (AZO) nanowires were manufactured at a low cost; for this purpose, a fast and simple fabrication process that involved dropping nanowires dispersion solution was employed instead of the conventional e-beam lithography process that is used to manufacture single nanowire–based UV photodetectors. It was demonstrated that nanowire network–based UV photodetectors provide a much faster UV photoresponse than conventional single nanowire–based UV photodetectors. The fast UV photoresponse of the fabricated UV photodetector can be attributed to the fact that the potential barriers formed in the nanowire network junctions effectively block the flow of electrons during the process of photocurrent decay. Furthermore, the UV photoresponse under illumination by a 254 nm UV source was studied as a function of the annealing temperature of the AZO nanowires network at a bias of 5 V. The fabricated UV photodetector showed the fastest response of 2 s to UV illumination in air when the sample was annealed in air for 1 h at 300 °C. 相似文献
995.
Il-Suk Kang Young-Su Kim Hyun-Sang Seo Chi Won Ahn Jun-Mo Yang Wook-Jung Hwang 《Current Applied Physics》2011,11(6):1319-1321
The effect of two-step hydrogenation, consisting of plasma hydrogenation and annealing in hydrogen, on the hysteresis phenomenon of metal-induced unilaterally crystallized silicon thin-film transistors (MIUC-Si TFTs) was investigated. The large hysteresis level of the conventional MIUC-Si TFTs caused a wide variation of the drain current with the previous gate voltage. As the plasma exposure time increased, the plasma hydrogenation commonly used for stability in poly-Si TFTs was found to increase the hysteresis level of MIUC-Si TFTs after a minimum point. This is because plasma-induced damages correlated with unique defects of MIUC-Si such as metal-related weak bonds, are accompanied by passivation. The following annealing repaired the damages. Consequently the hysteresis level was lower, which resulted in a narrower variation of the drain current. 相似文献
996.
The effect of ultrathin Fe underlayer on the strong in-plane magnetization of FePt magnetic thin film was investigated. This FePt thin film could be attained using the ultrathin Fe underlayer with 1 nm thickness. The in-plane coercivity of FePt film with 20 nm thickness grown on ultrathin Fe underlayer was high up to 7400 Oe. However, its out-of-plane coercivity was extremely low to 350 Oe compared to those of FePt thin films in other conventional studies. This result indicates that FePt thin film was strongly in-plane magnetized by ultrathin Fe underlayer. The strong ordering phase transformation kinetics and the high texturing to in-plane direction of the FePt thin film by ultrathin Fe underlayer were confirmed by Kinetics Monte Carlo (KMC) simulation and XRD measurement result, respectively. It is also supposed that they are associated with the reduction of an interface free energy between the film and the substrate with an introduction of ultrathin underlayer. 相似文献
997.
Yi Liu Tao Zou Fen Wang Chang-Hui Li Lin Zheng Young Sun 《Physica B: Condensed Matter》2011,406(6-7):1263-1266
We report on exotic dielectric properties of composite materials consisting of traditional ferroelectric BaTiO3 and electronic ferroelectric LuFe2O4. The composites were synthesized by a simple ceramic processing method with properties that can be tailored by adjusting LuFe2O4 concentration. A percolative effect was observed at the volume fraction of ~0.26, which led to an abrupt increase in the dielectric permittivity. For composites with high LuFe2O4 fractions, a giant dielectric tunability was observed over a broad temperature interval, which is in strong contrast to traditional ferroelectrics. 相似文献
998.
Xiao-Fei ZhangQing Xu Han-Xing LiuWen Chen Min Chen Bok-Hee Kim 《Physica B: Condensed Matter》2011,406(8):1571-1576
Nonlinear dielectric properties of Ba0.6Sr0.4TiO3 ceramics prepared by citrate method were investigated under bias electric field with respect to field history. X-ray diffraction analysis and temperature dependence of the dielectric constant (εr) confirmed a macroscopically paraelectric state for the specimen at room temperature. A slim polarization versus electric field (P-E) hysteresis loop of the specimen at room temperature indicated the existence of polar nano-regions (PNRs) superimposed on the paraelectric background. The nonlinear dielectric properties in continuous cycles of bias field sweep displayed a strong sensitivity to the field history. This phenomenon was qualitatively explained in terms of an irreversible polarization evolution of the PNRs under the bias fields. A considerable decline of the tunability with the cycle number suggests an appreciable contribution of the PNRs to the dielectric nonlinearity. The polarization and size of the PNRs were determined by fitting the dielectric constants to a multipolarization mechanism model. 相似文献
999.
Objectives
The present study was performed to examine which factors among self-rated scales, perceptual evaluations, and acoustic parameters, calculated from sustained vowels, are reliable indicators of physical and mental fatigues.Methods
A total of 73 volunteers (male:female, 52:21), aged 19–24 years, were enrolled in this study. We defined the high- and low-fatigue groups using the Chalder Fatigue Scale score. For assessment of self-rated symptoms, each subject was asked to complete Voice Handicap Index (VHI) and Voice Rating Scale (VRS). For perceptual evaluations, three clinicians assessed each subject’s vocal quality on the Grade, Roughness, Breathiness, Asthenia, Strain Scale. For acoustic analysis, each subject was asked to produce sustained vowels /a/, /e/, /i/, /o/, and /u/ for 3 seconds. Then, the habitual fundamental frequency (F0), jitter, shimmer, F0 tremor, mean F0, standard deviation of F0, maximum F0, minimum F0, normalized noise energy, harmonic-to-noise ratio (HNR), signal-to-noise ratio (SNR), amplitude tremor, and ratio within 2–4 kHz were calculated using Dr. Speech software.Results
In men, VHI, VRS, F0 tremor, shimmer, HNR, SNR, and amplitude tremor were related to mental fatigue. In women, only VHI was related to physical fatigue, and none of the acoustic parameters was related to the fatigue score. Perceptual evaluations were not related to fatigue in men or women.Conclusions
These findings suggest that self-rated symptoms and acoustic parameters related to voice quality are indicative of mental fatigue, and these features are prominent in men. 相似文献1000.
Hyun-Seo Park 《Thermophysics and Aeromechanics》2011,18(2):313-321
The paper presents the investigation of plasma melting of the mixed bottom and fly incineration ash at various mixing ratios
of the components. Chemical compound of the bottom and fly ash as well as the slag after its melting was analyzed by different
methods, and the content of toxic components in them was determined. It is demonstrated that the direct disposal of the fly
and bottom incineration ash may cause dioxin and heavy metal contamination of the environment. The influence of melted ash
basicity on the resulting slag compound was studied. The mass balance of the melting process was defined. The tests were performed
to determine the heavy-metals leaching from the ash and slag. It is also shown that the slag after plasma melting is dioxin-free
and environmentally friendly. 相似文献