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261.
Pekka Lahti 《International Journal of Theoretical Physics》2003,42(5):893-906
This talk is a survey of the question of joint measurability of coexistent observables and it is based on the monograph Operational Quantum Physics (Busch et al., Springer-Verlag, Berlin, 1997) and on the papers (Lahti et al., Journal of Mathematical Physics
39, 6364–6371, 1998; Lahti and Pulmannova, Reports on Mathematical Physics
39, 339–351, 1997; 47, 199–212, 2001). 相似文献
262.
Paul M. Lahti 《International journal of quantum chemistry》1992,44(5):785-794
AM 1 SCF -MO -CI computations find the bisected biphenyl dication to have nearly degenerate triplet and singlet states, with the lowest-energy state being a quininoid singlet planar dication. The bisected perchlorobiphenyl dication favors a triplet ground state by a small amount (0.4-1.9 kcal/mol), in qualitative agreement with recent experimental findings and with theoretical expectations that such an orthogonal open-shell pi-system should exhibit ferromagnetic exchange coupling. The higher oligomeric bisected para-linked phenylenes polycations do not show an appreciable computational preference for a high-spin multiplicity ground state either with or without perchlorine substitution. Chlorine substitution para to the 1,1′-linkage may lend a unique stabilization to the biphenyl system, which is not available in higher oligomeric analogs of poly(1,4-phenylene)s. The small magnitude of ferromagnetic exchange in these systems suggests that small geometric or substituent effects may confound experimental efforts to design polymeric ferromagnetic materials by this strategy. © 1992 John Wiley & Sons, Inc. 相似文献
263.
Comparative, fully relativistic (FR), scalar relativistic (SR) and non-relativistic (NR) DFT calculations attribute about 30% of the mercury-battery voltage to relativity. The obtained percentage is smaller than for the lead-acid battery, but not negligible. 相似文献
264.
Beus Maja Persoons Leentje Daelemans Dirk Schols Dominique Savijoki Kirsi Varmanen Pekka Yli-Kauhaluoma Jari Pavić Kristina Zorc Branka 《Molecular diversity》2022,26(5):2595-2612
Molecular Diversity - In the present study, we report the design and synthesis of novel amide-type hybrid molecules based on anthranilic acid and quinoline or β-carboline heterocyclic... 相似文献
265.
In earlier studies the methods for determination of chlorine by aluminium monochloride molecular absorption spectrometry have been based on the use of the continuous light sources. In this study we investigated the molecular absorption of AlCl in a carbon rod furnance for determination of chlorine, by using the lead atomic line at 261.418 nm emitted from a Pb-hollow cathode lamp. A deuterium lamp was used for simultaneous back-ground correction. 相似文献
266.
The present study was conducted to investigate the molecular absorption of sulfur dioxide in a carbon rod furnace for the determination of sulfur. The arsenic atomic line at 206.98 nm emitted from an As-hollow cathode lamp was used as an irradiation source in the measurements. The interferences caused by molecular absorption of some other molecules present in these conditions was also examined. Using the ionexchange as the pretreatment for the sample the method can be applied for a great variety of inorganic samples. 相似文献
267.
Jonna Salminen Tuire Koponen Pekka Räsänen Mikko Aro 《Mathematical Thinking and Learning》2013,15(4):273-295
Weaknesses in early number skills have been found to be a risk factor for later difficulties in mathematical performance. Nevertheless, only a few intervention studies with young children have been published. In this study, the responsiveness to early support in kindergarteners with most severe difficulties was examined with two different computer programs. Two intervention groups were matched by age, visuo-spatial, and phonological working memory, as well as early number skills. After a short and intensive computerized intervention, the results indicated significant intervention effects for verbal counting Wilcoxon ES (r) = 0.46, and dot counting fluency, r = 0.52, when practiced with GraphoGame Math, as well as for basic arithmetic, r = 0.63, when practiced with Number Race. The findings suggest that a targeted computerized practice can produce specific training effects in kindergarteners most at-risk for mathematics difficulties. The results are discussed with regard to practical implications for educational game development. 相似文献
268.
One common way to describe one's voice in an objective way is to measure the sound levels of the softest (pianissimo) and loudest possible (fortissimo) phonations at given pitches (voice range profile measurement). However, the reliability of the measurement has not been thoroughly investigated. The aim of the present study was to describe the repeatability and reproducibility of the sound level measurement in statistical terms, focusing on five target frequencies within the estimated speaking pitch range. Ten healthy female university students volunteered as test subjects. The voice range profiles within the speaking pitch range were defined 10 times in succession and in five sample sessions between 45-minute-long oral readings. Our study followed the ideas of the Gage repeatability and reproducibility design. The results showed that the method used was reliable in fortissimo phonations at four of the measured frequencies. Better reliability can be achieved by measuring three successive phonations at each pitch prior to the next target tone. 相似文献
269.
In Benjamini and Schramm [BS01] introduced the notion of distributional limit of a sequence of graphs with uniformly bounded valence and studied such limits in the case that the involved graphs are planar. We investigate distributional limits of sequences of Riemannian manifolds with bounded curvature which satisfy a quasi-conformal condition. We then apply our results to somewhat improve Benjamini’s and Schramm’s original result on the recurrence of the simple random walk on limits of planar graphs. For instance, as an application we give a proof of the fact that for graphs in an expander family, the genus of each graph is bounded from below by a linear function of the number of vertices. 相似文献
270.