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571.
Bell inequalities were created with the goal of improving the understanding of foundational questions in quantum mechanics. To this end, they are typically applied to measurement results generated from entangled systems of particles. They can, however, also be used as a statistical tool for macroscopic systems, where they can describe the connection strength between two components of a system under a causal model. We show that, in principle, data from macroscopic observations analyzed with Bell’ s approach can invalidate certain causal models. To illustrate this use, we describe a macroscopic game setting, without a quantum mechanical measurement process, and analyze it using the framework of Bell experiments. In the macroscopic game, violations of the inequalities can be created by cheating with classically defined strategies. In the physical context, the meaning of violations is less clear and is still vigorously debated. We discuss two measures for optimal strategies to generate a given statistic that violates the inequalities. We show their mathematical equivalence and how they can be computed from CHSH-quantities alone, if non-signaling applies. As a macroscopic example from the financial world, we show how the unfair use of insider knowledge could be picked up using Bell statistics. Finally, in the discussion of realist interpretations of quantum mechanical Bell experiments, cheating strategies are often expressed through the ideas of free choice and locality. In this regard, violations of free choice and locality can be interpreted as two sides of the same coin, which underscores the view that the meaning these terms are given in Bell’s approach should not be confused with their everyday use. In general, we conclude that Bell’s approach also carries lessons for understanding macroscopic systems of which the connectedness conforms to different causal structures. 相似文献
572.
Gustavo A. Narvaez Pawel Hawrylak Jos A. Brum 《Physica E: Low-dimensional Systems and Nanostructures》2001,9(4)
The role of finite hole mass on the ground and excited states of the negatively charged exciton in two dimensions is discussed. We present results of configuration-interaction calculation using exact excitonic states and results of a variational calculation of the ground-state energy to elucidate the interplay of finite hole mass and electron–electron interactions. 相似文献
573.
Arthur Mucha Roman Tyka Pawel Kafarski Tadeusz Glowiak Anna Goplaska 《Heteroatom Chemistry》1995,6(5):433-441
A series of previously unknown α-guanidinoalkanephosphonous, α- and β-guanidinoalkanephosphonic acids has been prepared in order to study their structures and biological activity. Aminoalkanephosphonous and phosphonic acids have been converted into their guanidino derivatives by means of S-methylisothiourea hydroiodide or cyanamide amidination. The crystal and molecular structures of three guanidino acids have been determined by single-crystal X-ray diffraction. The plant growth regulating activity of all synthesized guanidinoalkanephosphinates and phosphonates has been evaluated on Lepidium sativum. © 1995 John Wiley & Sons, Inc. 相似文献
574.
Tadeusz Błaszczyk Danuta Kaźmierczak Pawel Krzyczmonik Henryk Scholl Krzysztof Polański 《Journal of Solid State Electrochemistry》2000,4(2):95-106
The oxidation of cobalt electrodes has been carried out by means of cyclic voltammetry and coulometry under controlled potential
in sulfuric acid solutions of different concentrations. The electrochemical scanning tunneling microscope/scanning tunneling
microscope (ECSTM/STM) systems constructed by the authors and scanning electron microscopy (SEM) with the SEM-EDX system of
surface analysis of the elements have been used. The procedure applied in this work made it possible to observe the fragments
of the same surface by means of SEM and ECSTM/STM. The most typical images for a polycrystalline Co electrode with a ±10%
accuracy at the scales of 4800 nm × 4800 nm and 100 nm × 100 nm are presented and the results are discussed. In a diluted
electrolyte (0.1 M), irregular forms of a stable cobalt oxide with Co:O ratio ∼1:1 appear. Unreproducible results have been
obtained in a 1.0 M H2SO4 solution. Compact and relatively regular layers of cobalt oxide of the same ratio have been obtained in 0.1 M H2SO4, as well as in 10.0 M sulfuric acid solution, under controlled oxidation potential at the passivation range.
Received: 6 January 1999 / Accepted: 5 May 1999 相似文献
575.
Cumulative Atomic Multipole Moments were calculated for all natural amino acids and symmetric cyclic hexapeptides within Self‐Consisted Field (SCF) and Density Functional Theory (DFT) approaches using a standard 6‐31G(d,p) basis set. These data were used to analyze in detail the quality and the conformational and the intermolecular transferability of molecular charge distributions expressed in the atomic multipole form. Intermolecular interaction energies were reproduced reasonably by CAMM transformed from other conformations. Good transferability of CAMM based model was also achieved between similar molecular environments, which opens a route to modeling electrostatic effects in highly symmetric (e.g., crystalline) systems. Transferability deficiencies of various charge distribution models were analyzed and attributed to different levels of multipole expansion. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1082–1097, 2001 相似文献
576.
Tomáš Grygar Petr Bezdička Pawel Piszora Emilia Wolska 《Journal of Solid State Electrochemistry》2001,5(7-8):487-494
Electrochemical reductive dissolution of Li–Mn–O and Li–Fe–Mn–O spinels and Li+ extraction/insertion in these oxides were performed using voltammetry of microparticles. Both electrochemical reactions are
sensitive to the Fe/(Fe+Mn) ratio, specific surface area, Li content in tetrahedral positions, and Mn valence, and can be
used for electrochemical analysis of the homogeneity of the elemental and phase composition of synthetic samples. The peak
potential (E
P) of the reductive dissolution of the Li–Mn–O spinel is directly proportional to the logarithm of the specific surface area. E
P of Li–Fe–Mn–O spinels is mainly controlled by the Fe/(Fe+Mn) ratio. Li+ insertion/extraction can be performed with Mn-rich Li–Fe–Mn–O spinels in aqueous solution under an ambient atmosphere and
it is sensitive to the regularity of the spinel structure, in particularly to the amount of Li in tetrahedral positions and
the Mn valence.
Electronic Publication 相似文献
577.
Polynuclear ruthenium oxide/cyanoruthenate films on carbon substrates were grown by cycling the potential between 0.5 and 1.0 V (vs SCE) for 5–90 min in fresh 2 mM RuCl3·3 H2O, 2 mM K4Ru(CN)6·3 H2O, 0.5 M KCl solution at pH 2. During the positive scans, the cationic Ru(III,IV)-oxo polynuclear species interacted with the simultaneously formed anionic CN-bridged Ru dimers to yield sparingly soluble deposits on the electrode surfaces. Different thicknesses, typically corresponding to 2–50×10−10 mol cm−2, could be obtained by varying the cycling times. The absorption spectra of the coatings obtained at SnO2-covered glass electrodes were different from those known for RuO2 films and exhibited two absorption bands at about 400 and 700 nm. IR spectroscopic measurements confirmed the presence of a CN group in the deposit, as well as showing significant aquation of the entire coating. Ru, O, N and K (from KCl) were detected by means of Auger electron spectroscopy. The surface electrochemistry and stability of the film were significantly enhanced in K+-containing supporting electrolytes. The system provides a durable catalytic surface which allows the voltammetric oxidation of methanol; in 0.5 M H2SO4+0.5 M K2SO4 electrolyte the resulting anodic peak is at 1.01 V (vs. SCE). Electrooxidation was not possible at bare carbon electrodes, at least before the onset of the electrolyte decomposition. 相似文献
578.
Brian Herman Pawel Wodnicki Seongwook Kwon Ammasi Periasamy Gerald W. Gordon Nupam Mahajan Xue Feng Wang 《Journal of fluorescence》1997,7(1):85-91
Time-resolved fluorescence lifetime microscopy (TRFLM) allows the combination of the sensitivity of fluorescence lifetime
to environmental parameters to be monitored in a spatial manner in single living cells, as well as providing more accurate,
sensitive, and specific diagnosis of certain clinical diseases and chemical analyses. Here we discuss two applications of
TRFLM: (1) the use of nonratiometric probes such as Calcium Crimson, for measuring Ca2+; and (2) quantification of protein interaction in living cells using green and blue fluorescent protein (GFP and BFP, respectively)
expressing constructs in combination with fluorescence resonance energy transfer microscopy (FRET). With respect to measuring
Ca2+ in biological samples, we demonstrate thatintensity-based measurements of Ca2+ with single-wavelength Ca2+ probes such as Calcium Crimson may falsely report the actual Ca2+ concentration. This is due to effects of hydrophobicity of the local environment on the emission of Calcium Crimson as well
as interaction of Calcium Crimson with proteins, both of which are overcome by the use of TRFLM. The recent availability of
BFP (P4-3) and GFP (S65T) (which can serve as donor and acceptor, respectively) DNA sequences which can be attached to the
carboxy-or amino-terminal DNA sequence of specific proteins allows the dual expression and interaction of proteins conjugated
to BFP and GFP to be monitored in individual cells using FRET. Both of these applications of TRFLM are expected to enhance
substantially the information available regarding both the normal and the abnormal physiology of cells and tissues. 相似文献
579.
Pawel Pohl Anna Lesniewicz Wieslaw Zyrnicki 《International journal of environmental analytical chemistry》2013,93(11):963-970
Hydride generation inductively coupled plasma atomic emission spectrometry (HG-ICP-AES) in the system with aerosolised sample introduction has been employed for the first time for analysis of conifer needles. Arsenic, bismuth, antimony and tin along with other trace elements were simultaneously determined in pine, spruce, yew and thuja foliage sampled from various locations in Poland and Norway. Quality of the measurements was assured by examination of two attested plant reference materials. The application of different analyte introduction techniques and interference effects from matrix elements, i.e. Na, K, Mg, Ca and transition metals in the analysis of needles are discussed. 相似文献
580.