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351.
Ilpo Rasanen Ilkka Ojanper Juhani Vartiovaara Erkki Vuori Pekka Sunila 《Journal of separation science》1996,19(6):313-321
A dual-column gas chromatographic retention index method was evaluated for the toxicological screening for basic drugs in autopsy blood samples. The dual-column approach with DB-5 and DB-1701 capillary columns doubles the Identification Power of the corresponding single column methods. The long-term intralaboratory variation of the dialkylfluoroaniline series based retention indices of drugs in blood ranged from 0.03% to 0.2% which was generally better than that obtained using the relative retention time. Novel software is described for the processing and reporting of the dual-column chromatographic data in analytically useful form. Besides retention data, the response factors served as an additional identification factor. 相似文献
352.
Juha Heinonen Pekka Pankka Kai Rajala 《Archive for Rational Mechanics and Analysis》2010,196(3):839-866
We consider n-tuples of differential 1-forms in the Euclidean n-space that satisfy a quasiconformality condition and an asymptotic closedness condition. We show that renormalized sequences
of such tuples have subsequences converging to differentials of quasiregular maps. We then use these maps to show that the
tuples carry topological information. 相似文献
353.
We deal with the obstacle problem for the porous medium equation in the slow diffusion regime . Our main interest is to treat fairly irregular obstacles assuming only boundedness and lower semicontinuity. In particular, the considered obstacles are not regular enough to work with the classical notion of variational solutions, and a different approach is needed. We prove the existence of a solution in the sense of the minimal supersolution lying above the obstacle. As a consequence, we can show that non-negative weak supersolutions to the porous medium equation can be approximated by a sequence of supersolutions which are bounded away from zero. 相似文献
354.
Given the ever-growing awareness on global warming, much interest has focused on new and effective ways to manage energy, especially by harvesting and exploiting low-temperature heat sources, ubiquitous in the modern environment. Here, the holy grail is the direct conversion of heat into electricity especially using thermoelectric devices, and in this contribution, we focus on thermoelectrochemical systems.We give a brief overview of the most common thermally regenerative electrochemical cells developed nowadays with a short overview of their thermodynamic derivation, and we collect some of the most recent results in terms of their thermoelectrochemical properties, in particular, their temperature coefficients. We see that although the most used redox couples are based on Fe3+/Fe2+ and their derivates, thermodiffusion effects and other entropy-related phenomena are attracting the attention of the scientific community and boosting astonishing results. On the other hand, thermally regenerative batteries are emerging, showing modest performance. 相似文献
355.
Pekka J. Korhonen Pekka Malo Tommi Pajala Niklas Ravaja Outi Somervuori Jyrki Wallenius 《European Journal of Operational Research》2018,264(1):270-279
We show that contextual variables in a Multiple Criteria Decision Making task influence choice quality. Based on an experiment we investigate the effects of product type, emotional attachment, and the amount and structure of information provided. We measured choice quality with nondominance, which is a desirable property of good choices. Regarding the product type effect, we distinguish between hedonic products that primarily are desirable due to affect, and utilitarian products, which are desirable because they are useful. When subjects with high emotional attachment make choices with hedonic products, they make fewer dominated choices than with utilitarian products. Further, we show that information overload is a relevant phenomenon in MCDM experiments. However, what matters is the quality of information, not just the quantity. When we add information that does not change the dominance relations between products, choice quality is not degraded. 相似文献
356.
Sukhomlinov Dmitry Tesfaye Fiseha Hellstén Niko Lindberg Daniel Taskinen Pekka 《Journal of Solid State Electrochemistry》2018,22(4):959-972
Journal of Solid State Electrochemistry - Thermodynamic properties of solid phases in the Cu–O–Al2O3 system were measured by means of the EMF method with oxygen concentration galvanic... 相似文献
357.
Quasi‐relativistic Douglas–Kroll CASPT2 calculations are reported for the title molecules, mainly to provide primary data for a fit of double‐bond covalent radii. Indeed, a well‐developed σ2π2 double bond is identified in all cases. For Eu and Yb, however, it is an excited state. The main valence orbitals of all Ln ions are 6s and 5d. In the σ bonds, more 5d than 6s character is found at the Ln. The Ln?C bond lengths show a systematic lanthanide contraction of 13 pm from La to Lu. An agostic symmetry breaking is demonstrated for Ce but its effect on the Ln? C length is small. 相似文献
358.
The electronic structures, as well as spectroscopic and thermodynamic properties of the title Pu@M12 clusters, are considered at the density functional theory level. In both cases, a Pu2+ ion is encapsulated in an icosahedral, stanna- or plumbaspherene cage. As suggested before for M = Pb, both systems are reported to follow a 32-electron principle for the central atom. 相似文献
359.
In this paper we investigate the coupling properties of pairs of quadrature observables, showing that, apart from the Weyl relation, they share the same coupling properties as the position-momentum pair. In particular, they are complementary. We determine the marginal observables of a covariant phase space observable with respect to an arbitrary rotated reference frame, and observe that these marginal observables are unsharp quadrature observables. The related distributions constitute the Radon transform of a phase space distribution of the covariant phase space observable. Since the quadrature distributions are the Radon transform of the Wigner function of a state, we also exhibit the relation between the quadrature observables and the tomography observable, and show how to construct the phase space observable from the quadrature observables. Finally, we give a method to measure together with a single measurement scheme any complementary pair of quadrature observables. 相似文献
360.
Akram Dehnokhalaji Pekka J. Korhonen Murat Köksalan Nasim Nasrabadi Jyrki Wallenius 《European Journal of Operational Research》2010
We develop an approach to efficiency analysis to enable us to incorporate interval-scale data in addition to ratio-scale data. Our approach introduces a measure of inefficiency and identifies efficient units as is done in Data Envelopment Analysis. The basic idea in our approach is to find the “best” hyperplane separating the units that are better and worse than each unit. “Best” is defined in such a way that the number of not-better units is maximal. The efficiency measure is defined as a proportion of not-better units to all units. The results are invariant under a strictly increasing linear re-scaling of any input- or output-variables. Thus zeroes or negative values do not cause problems for the analysis. The approach is used to analyze the data of the research evaluation exercise recently carried out at the University of Joensuu, Finland. 相似文献