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41.
Rabindra N. Roy Lakshmi N. Roy Kathleen A. Allen Casey J. Mehrhoff Isaac B. Henson Jessica M. Stegner Alexis L. Jenkins Ankita A. Shah Stephen D. Rocchio 《Journal of solution chemistry》2012,41(6):1044-1053
In this study, we report the pH values of two buffer solutions without chloride ion and eight buffer solutions with NaCl with an ionic strength I=0.16 mol?kg?1. Electromotive force (emf) techniques have been used to get the cell potentials at 12 temperatures from 5 to 55?°C, including 37?°C. An extended form of the Bates-Guggenheim convention is used in the entire ionic strength range, 0.04 to 0.16?mol?kg?1. The residual liquid junction potentials (??E j ) of the buffer solutions of MOBS have been estimated from previous measurements with a flowing junction cell. These values of ??E j have been used for correction in order to ascertain the operational pH values of four buffer solutions of MOBS at 25 and 37?°C. These solutions are recommended as pH standards for physiological application in the pH range 7.4 to 7.7. 相似文献
42.
Dr. Isaac Omari Dr. Lars P. E. Yunker Dr. Johanne Penafiel Darlene Gitaari Atzin San Roman Prof. J. Scott McIndoe 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(11):3812-3816
Organotrifluoroborates serve as coupling partners during transmetalation in the Suzuki–Miyaura reaction but require hydrolysis prior to the coupling reaction. Their anionic nature allows study of their hydrolysis by electrospray ionization mass spectrometry (ESI-MS) through real-time monitoring, complemented by pH analysis. The induction period varied according to the borates employed, and a dynamic series of equilibria for numerous ions was observed during hydrolysis. We found that the induction periods and reaction rates were sensitive to the R group of the borates, the shape of the reaction vessel, and stir rate. 相似文献
43.
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Mathematische Zeitschrift - 相似文献
46.
Isochores of solid H2 and D2 have been measured to 2 kbar. Our results lead to reevaluation of the 4.2 K isotherm of Anderson and Swenson to 25 kbar. The equation of state has been determined, including ortho-para dependence. The pre-melting phase transition cited in recent russian literature has not been detected. 相似文献
47.
Isaac M. Daniel 《Experimental Mechanics》1985,25(4):413-420
The behavior of quasi-isotropic graphite/epoxy laminates with cracks subjected to various biaxial-stress fields was studied
experimentally. This was accomplished by uniaxial tensile loading of specimens with cracks of various orientations with the
loading axis. It was found that the critical stress-intensity factor, based on a projected crack length increased by a characteristic
damage dimension, is nearly constant with stress biaxiality and initial crack length.
Paper was presented at V International Congress on Experimental Mechanics held in Montreal, Quebec, Canada on June 10–15,
1984. 相似文献
48.
Electromagnetically induced transparency is an effect observed in atomic systems, originating from quantum interference, in which electromagnetic transitions to and from a certain quantum state become suppressed. This dark state is also characterized by a quantum phase, relative to other states, which theoretically should stop evolving, but remain phase coherent, during transparency. We test this theoretical prediction using techniques developed for liquid-state nuclear magnetic resonance quantum computation, applied to a spin-7/2 nuclear spin system. A sequence of quantum operations is applied to create the dark state, and during transparency its phase evolution is measured relative to a reference state using Ramsey interferometry. Experimental measurements of the fringe visibility are in excellent agreement with theoretical expectations, taking into account measured decoherence rates. 相似文献
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We report the realization of a nuclear magnetic resonance computer with three quantum bits that simulates an adiabatic quantum optimization algorithm. Adiabatic quantum algorithms offer new insight into how quantum resources can be used to solve hard problems. This experiment uses a particularly well-suited three quantum bit molecule and was made possible by introducing a technique that encodes general instances of the given optimization problem into an easily applicable Hamiltonian. Our results indicate an optimal run time of the adiabatic algorithm that agrees well with the prediction of a simple decoherence model. 相似文献