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91.
Going beyond the entanglement of microscopic objects (such as photons, spins, and ions), here we propose an efficient approach to produce and control the quantum entanglement of three macroscopic coupled superconducting qubits. By conditionally rotating, one by one, selected Josephson-charge qubits, we show that their Greenberger-Horne-Zeilinger (GHZ) entangled states can be deterministically generated. The existence of GHZ correlations between these qubits could be experimentally demonstrated by effective single-qubit operations followed by high-fidelity single-shot readouts. The possibility of using the prepared GHZ correlations to test the macroscopic conflict between the noncommutativity of quantum mechanics and the commutativity of classical physics is also discussed.  相似文献   
92.
93.
In this paper, the DVRT (vector radiative transfer theory of densely distributed random discrete scatters) model to calculate the brightness temperature emitted by radiometer calibration load is presented. It takes the multiple scattering of isolation layer into account, which is neglected by the incoherent homogeneous model often used in calibration. Hence, it works much better than incoherent homogeneous model at millimeter wave band. Furthermore, the iteration of DVRT model is presented, and it proves that the incoherent homogeneous model is just the zero-order solution of DVRT model. Some numerical results are provided in the end.  相似文献   
94.
Main observation and conclusion The enzyme AbyU catalyses a Diels-Alder (DA) reaction during abyssomicin C biosynthesis.In this study,AbyU is shown to convert t...  相似文献   
95.
Main observation and conclusion With the rapid development of the wearable electronics,the flexible supercapacitor with high energy density has attracted more a...  相似文献   
96.
3-Carboxy-2-pyrazinehydroxamic acid was prepared by a one pot reaction starting from pyrazine-2,3-dicarboxylic anhydride with a high yield, and characterized by IR, Mass spectrum, 1H NMR and 13C NMR spectra and single-crystal X-ray diffraction. It crystallizes in triclinic, space group Pī with a=4.8659(10), b=7.4233(15), c=11.602(2), α=96.904(2), β=92.422(3), γ=107.454(2)°, V=395.51(14)3 , Z=2, Dc=1.689g/cm3 , F(000)=208, μ(MoKα)=0.149 mm-1 , the final R=0.0473 and wR=0.1306 for 2853 observed reflections (I>2σ (I)). A three-dimensional framework was assembled through intermolecular hydrogen bonding between water and 3-carboxy-2-pyrazine-carbohydroxamic acid molecules.  相似文献   
97.
Abstract

Optical patterns for the polarizing microscope textures of closed cylinders of liquid crystals (CCLCs) are studied by the Jones vector formulation. The simulated director configuration diagram of a CCLC with normal orientation at the walls contains four kinds of stable director configurations. The resulting texture under some approximations depends only on phase shifts. The patterns are characterized by dark brushes that coincide with the directions of the crossed polarizers. Additionally, there are concentric circle fringes. For the ring defect structure, the centre region of the cylinder exhibits a black extinction. However, this is not distinguishable as between the hyperbolic and radial structures for both the point and the ring defect patterns. Comparing the observed patterns with the simulated ones, we find that the dark cross brushes and the centre black extinction of simulated patterns are similar to those that are observed. However, the concentric circle fringes of the observed pattern are not in accordance with the simulated pattern.  相似文献   
98.
A simple and sensitive HPLC method using UV detection was developed to determine the concentration of protoapigenone in rat plasma. Chromatographic separation was conducted on a C18 column with a mobile phase consisting of an acetonitrile–methanol–aqueous phase (containing 0.2% acetic acid, pH 3.0) system at a flow rate of 1.0 mL/min. The UV detector was set at 248 nm. The calibration curve was linear over the range of 0.031–10.0 µg/mL. The lower limit of quantification was 31 ng/mL. The recoveries for plasma samples ranged from 70.3 to 82.5%. The intra‐ and inter‐day accuracy and precision fulfilled the international standards. This method was successfully applied to a pharmacokinetic study of protoapigenone in rats after oral administration of protoapigenone. It was shown that protoapigenone could be absorbed rapidly after oral administration and could reach the maximum concentration within 1 h. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
99.
The sorption capacity of cesium (Cs) and selenium (Se) in crushed mudrock was demonstrated in this study through a 2-site Langmuir model. To employ such a numerical analysis, batch tests were applied in this study in synthetic seawater and groundwater with sorption/desorption kinetic experiments (time-dependent) and different concentrations (10?2–10?7 M). The 2-site sorption models, which correspond to two rate constants (λ 1 and λ 2), might be more adequate than 1-site sorption models in characterizing Cs and Se sorption/desorption according to the least square errors between the numerical analysis and the results of the batch tests. The fitting results showed that a 2-site Langmuir model is capable of appropriately describing Cs and Se sorption in mudrock. Consequently, the sorption capacity was calculated at about 0.06 mol/kg for Cs and at 0.015 mol/kg for Se.  相似文献   
100.
An unusual substitution reaction of an aromatic sulfonic group based on 3-carbonyl-4-phenolsulfonic acid was discovered in a diazo-coupling process.The reaction occurred under mild reaction conditions (pH 8.0-9.0.0-5 C,solvent:water) within a short reaction time(1h).A plausible substitution reaction mechanism by phenol-ketone resonance was proposed.  相似文献   
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