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61.
Baudry Y Pasini D Nishihara M Sakai N Matile S 《Chemical communications (Cambridge, England)》2005,(38):4798-4800
Voltage-sensitive blockage by ADP, ATP and phytate (IP6) demonstrates that active-site contraction toward the middle of newly synthesized rigid-rod beta-barrels provides a general strategy to rationally create and modulate the voltage sensitivity (and to increase the efficiency) of molecular recognition by synthetic multifunctional pores. 相似文献
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Vladimir Chaloupka Claude Bricman Angela Barbaro-Galtieri Denyse M. Chew Robert L. Kelly Thomas A. Lasinski Alan Rittenberg Arthur H. Rosenfeld Thomas G. Trippe Fumiyo Uchiyama Naomi Barash-Schmidt Paul Söding Matts Roos 《Physics letters. [Part B]》1974,50(1):i
This review of the properties of leptons, mesons, and baryons is an updating of Review of Particle Properties, Particle Data Group [Rev. Mod. Phys. 45, No. 2, Part II, Supplement (1973)]. Data are evaluated, listed, averaged, and summarized in tables. 相似文献
65.
Tsuchiya T Wakahara T Lian Y Maeda Y Akasaka T Kato T Mizorogi N Nagase S 《The journal of physical chemistry. B》2006,110(45):22517-22520
A preferential extraction of endohedral metallofullerenes (EMFs) from carbon soot through the use of reduction in the extraction process and a convenient isolation of endohedral metallofullerene anions (EMFs(-)) and empty fullerenes utilizing their difference in solubility are accomplished. EMFs are easily isolated by one-stage high-performance liquid chromatography after chemical oxidation of the extracted endohedral EMFs(-). 相似文献
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The pressure required to drive flow through a microfluidic device is an important characteristic of that device. We present a method to measure the flow rate through microfluidic components and systems, including micropumps and microvalves. The measurement platform is composed of two pressure sensors and a glass tube, which provides series resistance. The principle of the measurement is the fluid dynamical equivalent of Ohm's law, which defines the relationship between current, resistance, and voltage that are analogues to flow rate, hydraulic resistance, and pressure drop, respectively. Once the series resistance is known, it is possible to compute the flow rate through a device based on pressure alone. In addition, the dynamic system characteristics of the device-resistance and capacitance-can be computed. The benefits of this method are its simple configuration, capability of measuring flow rate accurately from the more easily measured pressure, and the ability to predict the dynamic response of microfluidic devices. 相似文献
68.
The purpose of this paper is to prove that a primitive Hilbert cusp form \(\mathbf{g}\) is uniquely determined by the central values of the Rankin–Selberg L-functions \(L(\mathbf{f}\otimes \mathbf{g}, \frac{1}{2})\), where \(\mathbf{f}\) runs through all primitive Hilbert cusp forms of weight \(k\) for infinitely many weight vectors \(k\). This result is a generalization of the work of Ganguly et al. (Math Ann 345:843–857, 2009) to the setting of totally real number fields, and it is a weight aspect analogue of our previous work (Hamieh and Tanabe in Trans Am Math Soc, arXiv:1609.07209, 2016). 相似文献
69.
The internal friction Q?1 and Young’s modulus E of Zr–Ti–Cu–Ni–Be bulk metallic glass specimens were measured using a dynamical mechanical spectrometer. Temperature dependence measurements were carried out for differently heat-treated specimens from room temperature up to a temperature above the crystallization temperature using several vibration frequencies (0.2–25 Hz). Two types of Q?1 peaks appeared: a high-temperature peak in the supercooled region, and a medium-temperature peak in the glassy state region. Both of them were shown to be Arrhenius-type anelastic peaks. From the obtained results, the kinetics of movable atoms in the material were discussed. The amplitude dependence of the internal friction was measured at a given frequency at various temperatures. Fluctuations and rapid changes were observed in Q?1 when the amplitude was gradually increased. The fluctuations were especially large near the glass transition temperature. The results were considered on the basis of the dynamics of the atoms in glass-forming materials near the glass transition. 相似文献
70.
François N. Miros Guangxi Huang Yingjie Zhao Naomi Sakai 《Supramolecular chemistry》2015,27(5-6):303-309
Catalysis with anion–π interactions is emerging as an important topic in supramolecular chemistry. Among the reactions explored so far on π-acidic surfaces, coumarin synthesis stands out as a cascade process with several coupled anionic transition states. Increasing π-acidity has been shown in a different context to increase transition-state stabilisation and thus catalytic activity. In this report, we explore the possible use of macrocycles to accelerate coumarin synthesis between two π-acidic surfaces. To our disappointment, we found that compared to monomeric π-acids, coumarin synthesis within divalent macrocycles is clearly slower. Hindered access to an overly confined active site within the macrocycles could possibly account for this loss in activity, but several other explanations are certainly possible. However, operational coumarin synthesis on monomeric π-acidic surfaces is shown to tolerate structural modifications. Best results are obtained with structures that aim for proximity without obstructing transition-state stabilisation on the π-acidic surface. 相似文献