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11.
Torbjørn Helvik Kristian Lindgren Mats G. Nordahl 《Communications in Mathematical Physics》2007,272(1):53-74
We introduce a local version of the Shannon entropy in order to describe information transport in spatially extended dynamical
systems, and to explore to what extent information can be viewed as a local quantity. Using an appropriately defined information
current, this quantity is shown to obey a local conservation law in the case of one-dimensional reversible cellular automata
with arbitrary initial measures. The result is also shown to apply to one-dimensional surjective cellular automata in the
case of shift-invariant measures. Bounds on the information flow are also shown. 相似文献
12.
Svante Wold Michael Sjöström Rolf Carlson Torbjörn Lundstedt Sven Hellberg Bert Skagerberg Conny Wikström Jerker Öhman 《Analytica chimica acta》1986
In multivariate data analysis such as principal components analysis (PCA) and projections to latent structures (PLS), it is essential that the training set systems (objects) are selected to provide data with substantial information for model parametrization, and to represent properly any future situations where the multilvariate model is used for predictions. In the framework of multivariate projections (PCA, SIMCA and PLS), elementary concepts of statistical design (fractional factorials and composite designs) can be used with the latent variables (PC or PLS scores) as design variables. The plan of action thus becomes: (1) problem formulation (specify aim and model, make a conceptual division of the investigated system into subsystems); (2) collection of multivariate data for each type of subsystems; (3) estimation of the practical dimensionality of the data for each type of subsystems by PC or PLS analysis; (4) use of the PC or PLS scores (t) as design variables in the combination of subsystems to systems in the training set; (5) measurement of responses (Y); (6) analysis of data by PCA or PLS; (7) interpretation of results with possible feedback to steps 1, 2 or 3. The procedures are illustrated by two problems: a structure/activity relationship for a family of peptides, and optimization of an organic synthesis with respect to system variables (solvent, substrate, co-reactant_) and process variables (temperature, reactant concentrations). 相似文献
13.
Carl‐Johan Wallentin Torbjörn Wixe Ola F. Wendt Dr. Karl‐Erik Bergquist Dr. Kenneth Wärnmark Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(13):3994-4002
A pair of molecular tweezers (syn‐ 4 ) that consists of quinoline and pyrazine units fused to a bicyclic framework is presented. The tweezers were synthesised both as a racemic mixture (rac‐ 4 ) and an enantiomerically pure form ((R,R,R,R)‐ 4 ) starting from either racemic or enantiomerically pure bicyclo[3.3.1]nonane‐2,6‐dione ( 3 ). Homochiral dimers were observed in the solid state for rac‐ 4 . The self‐association of both rac‐ 4 and (R,R,R,R)‐ 4 was studied in solution. A weak self‐association constant in CDCl3 was estimated by 1H NMR spectroscopic dilution titration experiments in both cases, following several proton resonances. For this purpose, a general normalisation model for the accurate determination of association constants from multiple datasets was developed. In contrast to the solid state, no diastereomeric discrimination was observed for rac‐ 4 in solution. 相似文献
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Well‐Defined Palladium Nanoparticles Supported on Siliceous Mesocellular Foam as Heterogeneous Catalysts for the Oxidation of Water
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Dr. Oscar Verho Dr. Torbjörn Åkermark Dr. Eric V. Johnston Karl P. J. Gustafson Dr. Cheuk‐W. Tai Henrik Svengren Dr. Markus D. Kärkäs Prof. Jan‐E. Bäckvall Prof. Björn Åkermark 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(15):5909-5915
Herein, we describe the use of Pd nanoparticles immobilized on an amino‐functionalized siliceous mesocellular foam for the catalytic oxidation of H2O. The Pd nanocatalyst proved to be capable of mediating the four‐electron oxidation of H2O to O2, both chemically and photochemically. The Pd nanocatalyst is easy to prepare and shows high chemical stability, low leaching, and recyclability. Together with its promising catalytic activity, these features make the Pd nanocatalyst of potential interest for future sustainable solar‐fuel production. 相似文献
18.
Torbjörn Pettersson Johannes Hellwig Per-Johan Gustafsson Stig Stenström 《Cellulose (London, England)》2017,24(10):4139-4149
Flexibility and modulus of elasticity data for two types of wet cellulose fibres using a direct force–displacement method by means of AFM are reported for never dried wet fibres immersed in water. The flexibilities for the bleached softwood kraft pulp (BSW) fibres are in the range of 4–38 × 1012 N?1 m?2 while the flexibilities for the thermomechanical pulp (TMP) fibres are about one order of magnitude lower. For BSW the modulus of elasticity ranges from 1 to 12 MPa and for TMP between 15–190 MPa. These data are lower than most other available pulp fibre data and comparable to a soft rubber band. Reasons for the difference can be that our measurements with a direct method were performed using never dried fibres immersed in water while other groups have employed indirect methods using pulp with different treatments. 相似文献
19.
Pinto RC Stenlund H Hertzberg M Lundstedt T Johansson E Trygg J 《Analytica chimica acta》2011,(2):127-131
To find and ascertain phenotypic differences, minimal variation between biological replicates is always desired. Variation between the replicates can originate from genetic transformation but also from environmental effects in the greenhouse. Design of experiments (DoE) has been used in field trials for many years and proven its value but is underused within functional genomics including greenhouse experiments. We propose a strategy to estimate the effect of environmental factors with the ultimate goal of minimizing variation between biological replicates, based on DoE. DoE can be analyzed in many ways. We present a graphical solution together with solutions based on classical statistics as well as the newly developed OPLS methodology.In this study, we used DoE to evaluate the influence of plant specific factors (plant size, shoot type, plant quality, and amount of fertilizer) and rotation of plant positions on height and section area of 135 cloned wild type poplar trees grown in the greenhouse. Statistical analysis revealed that plant position was the main contributor to variability among biological replicates and applying a plant rotation scheme could reduce this variation. 相似文献
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