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11.
In this paper we present a versatile and scalable simulation code for the two- and three dimensional Ising model which can be used across different parallel acceleration frameworks (CUDA, OpenCL, OpenMP, MPI).  相似文献   
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Anhydrous EuII–acetylenedicarboxylate (EuADC; ADC2− = O2C-C≡C-CO2) was synthesized by reaction of EuBr2 with K2ADC or H2ADC in degassed water under oxygen-free conditions. EuADC crystallizes in the SrADC type structure (I41/amd, Z=4) forming a 3D coordination polymer with a diamond-like arrangement of Eu2+ nodes (msw topology including the connecting ADC2− linkers). Deep orange coloured EuADC is stable in air and starts decomposing upon heating in an argon atmosphere only at 440 °C. Measurements of the magnetic susceptibilities (μeff=7.76 μB) and 151Eu Mössbauer spectra (δ=−13.25 mm s−1 at 78 K) confirm the existence of Eu2+ cations. Diffuse reflectance spectra indicate a direct optical band gap of Eg=2.64 eV (470 nm), which is in accordance with the orange colour of the material. Surprisingly, EuADC does not show any photoluminescence under irradiation with UV light of different wavelengths. Similar to SrADC, EuADC exhibits a negative thermal volume expansion below room temperature with a volume expansion coefficient αV=−9.4(12)×10−6 K−1.  相似文献   
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Ona-Nguema  G.  Abdelmoula  M.  Jorand  F.  Benali  O.  Géhin  A.  Block  J.-C.  Génin  J.-M. R. 《Hyperfine Interactions》2002,139(1-4):231-237
Dissimilatory iron-reducing bacteria (DIRB) couple the oxidation of organic matter or H2 to the reduction of iron oxides. The bacterial reduction of a most common well-crystallised ferric oxyhydroxide, -FeOOH was investigated using DIRB Shewanella putrefaciens, strain CIP 8040. Experiments were conducted in the presence of neither organic buffer nor phosphate, with formate as electron donor, bicarbonate, and anthraquinone-2,6-disulfonate (AQDS, a humic acid analogue) that influenced the extent of ferric oxide bioreduction. The production of Fe2+ was followed with time. The solid phases obtained after bacterial iron reduction were analysed by transmission Mössbauer spectroscopy (TMS) and X-ray diffraction (XRD). Biogenic formation of green rust 1 compound, which contains carbonate anions, [FeII 2FeIII 2(OH)8]2+[CO3 2–]2– was observed. TMS was used to follow the evolution of the green rust abundance during the bacterial culture.  相似文献   
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Proton-antiproton and proton-proton elastic scattering have been measured in the four-momentum transfer range 0.001|t|0.06 GeV2 for center-of-mass energy 52.8 GeV at the CERN Intersecting Storage Rings (ISR). Using the known pp total cross section, a simultaneous fit to the p and pp differential cross sections yields the p total cross section; in addition, we obtain the ratio of the real-to-imaginary part of the forward nuclear-scattering amplitude and the nuclear-slope parameter for both p and pp. Our results show conclusively that the p total cross section is rising at ISR energies and lend support to conventional theories in which the difference between the p and pp total cross section vanishes at very high energy.  相似文献   
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We measured the neutron scattering intensities from pure liquid H2O relative to that of pure D2O and also relative to H2O-D2O mixtures, at room temperature. This study is relevant to the problem of quantum entanglement. The neutrons were generated from an electron Linac and the final energy of the scattered neutrons was fixed at 24.3 keV using a 20 cm thick pure iron filter. The scattering intensity ratios were found to agree with expected values deduced from the tabulated total cross sections within an accuracy of 3%. Thus no anomaly was observed.  相似文献   
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