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排序方式: 共有115条查询结果,搜索用时 406 毫秒
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Temperature–pressure phase diagram of the 2-D organic conductor, κ-(DHDA-TTP)2SbF6 (DHDA-TTP = 2-(1,3-dithiolan-2-ylidene)-5-(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene) is presented. This phase diagram exhibits a pressure boundary between insulator and Fermi liquid (FL). This boundary is considered as a critical pressure of quantum fluctuation between probable charge ordering and FL ground states. In the vicinity of the specific pressure, divergence of the prefactor A in ρ = ρ0 + AT2, is observed, where ρ is the in-plane resistivity and T is the temperature. Following the similar phase diagram to κ-(MeDH-TTP)2AsF6 by Yasuzuka et al., this is the second example in the two-dimensional 1/4-filled organic conductors, showing the temperature–pressure phase diagram of quantum critical behavior. It is remarkable that this kind of divergence of A at certain critical point is rather general phenomena at least in these 1/4-filled 2-D organic conductors, in contrast to the other 1/2-filled κ-type organic conductors, which show Kanoda's phase diagram with Mott insulator and superconductor.  相似文献   
84.
A 1-year randomized controlled trial examined effects of milk basic protein (MBP) supplementation (40 mg day?1) and daily physical activity (step count and duration of exercise > 3 metabolic equivalents [METs]) on bone metabolism, forearm bone mineral density (BMD) and a calcaneal osteosonic index (OSI) in 79 females aged 65–86 years. MBP did not affect osteocalcin or bone-specific alkaline phosphatase, but at 12 months, excretion of deoxypyridinoline and cross-linked N-teleopeptides of type I collagen (NTx) were significantly less than in controls. Experimental subjects also maintained BMD and had a 1.5% increase of OSI at 12 months. After adjustments for age and baseline bone parameters, osteocalcin, deoxypyridinoline, NTx and/or OSI at 12 months were significantly related to step count and/or duration of activity > 3 METs. MBP reduced markers of bone loss, particularly in the lower extremities. Reduced resorption of bone was also associated with moderate-intensity/duration exercise, MBP therapy interacting significantly with habitual physical activity.  相似文献   
85.
This paper presents a plain method of calculating the voltage waveform at motor input terminals from the inverter output terminal voltage and also a method of reducing the voltage. The voltage waveform at the motor input terminals is obtained by a frequency domain calculation using the transfer function of the cable and the frequency characteristics of the voltage waveform at the inverter output terminals. The analysis using this method clarifies the mechanism of the rise of the maximum voltage at the motor input terminals, that is, ringing at the motor input terminals, which occurs at specific frequencies at which the transfer gain increases, causing the rise of the maximum voltage. Therefore, to decrease the maximum voltage at the motor input terminals, it is effective to shorten the cable length or cancel the ringing voltage by preswitching. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(4): 11–19, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22482  相似文献   
86.
The chemokine receptor CXCR4 is a member of the seven transmembrane GPCR family, which is implicated in multiple diseases, including HIV infection, cancers, and rheumatoid arthritis. Low-molecular-weight nonpeptidic compounds, including AMD3100 and various pyridyl macrocyclic zinc(II) complexes, have been identified as selective antagonists of CXCR4. In the present study, structure-activity relationship studies were performed by combining the common structural features of alkylamino and pyridiyl macrocyclic antagonists. Several new zinc(II) or copper(II) complexes demonstrated potent anti-HIV activity, strong CXCR4-binding activity, and significant inhibitory activity against Ca(2+) mobilization induced by CXCL12 stimulation. These results may prove useful in the design of novel CXCR4 antagonists, and the compounds described could potentially be developed as therapeutics against CXCR4-relevant diseases or chemical probes to study the biological activity of CXCR4.  相似文献   
87.
Switching on kinases: Synthetic caged DAG-lactones have been developed and showed decreases of two orders of magnitude, relative to the corresponding parent compounds, in their binding affinities towards PKC. The caged compounds had no effect on the translocation of PKC until after photoactivation. This approach is a potentially powerful tool for probing the PKC signaling cascade.  相似文献   
88.
To achieve diversity with a single antenna, fractional sampling has been proposed. The imaging component of a desired signal must be transmitted by increasing the baseband filter bandwidth. This paper proposes and evaluates a system in which the imaging component is transmitted on the adjacent channel to the desired signal. The adjacent channel interference is cancelled by the precoding generated based on the basis of the channel state information of all the terminals. In this paper, the performance with perfect feedback and limited feedback is evaluated. Numerical results obtained through computer simulation show that the proposed scheme with a 6 bit random codebook for QPSK modulation improves the performance compared with that with the conventional scheme in the low $E_b/N_0$ region.  相似文献   
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We developed MDGRAPE-2, a hardware accelerator that calculates forces at high speed in molecular dynamics (MD) simulations. MDGRAPE-2 is connected to a PC or a workstation as an extension board. The sustained performance of one MDGRAPE-2 board is 15 Gflops, roughly equivalent to the peak performance of the fastest supercomputer processing element. One board is able to calculate all forces between 10 000 particles in 0.28 s (i.e. 310000 time steps per day). If 16 boards are connected to one computer and operated in parallel, this calculation speed becomes ∼10 times faster. In addition to MD, MDGRAPE-2 can be applied to gravitational N-body simulations, the vortex method and smoothed particle hydrodynamics in computational fluid dynamics.  相似文献   
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