Microkinetic analysis of the oxidative conversion of methane. Dependence of rate constants on the electrical properties of (CaO) x (CeO2)1−x catalysts

Elementary reaction steps of the oxidative conversion of methane to CO _x and ethane were derived from kinetic data for various (CaO) _x (CeO₂)_1–x catalysts. The rate constants depend on electron and O^2– conductivity as well as on the reducibility of the oxides. It is shown hereby that reactions resulting in increased or in decreased ethane selectivity are interrelated via the same catalyst properties.     

Language-driven concept learning: Deciphering Jabberwocky.

Four experiments assessed (Whorfian) effects of language on acquiring event categories. During learning, English-like spoken language accompanied animated scenes in some conditions. Lexical (novel verbs) and/or syntactic cues (either argument structures or prepositions) covaried with event category. Other conditions provided no language. All participants' knowledge of event categories was tested without language. Participants learned the event categories better when some aspect of language covaried with them (Experiments 1, 2, & 3; but not with sounds, Experiment 4), and better still when two aspects of language covaried (Experiments 1 & 3). However, multiple (Experiments 2 & 3) and individual language cues (Experiment 4) did not always facilitate learning. The effect of language is more complicated than providing feedback, as in supervised learning, or increasing systematicity, as in unsupervised learning. Language form induced specific expectations, with effects on learning analogous to the effects of prior theories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of Preparation Parameters on the Performance of Colloid-derived Oxidic Palladium Catalysts for Selective Hydrogenation of C–C Triple Bonds

(Hydr-) oxidic PdO _x H _y colloids were prepared by H₂PdCl₄ hydrolysis in presence of poly(vinylpyrrolidone) under pH control. After immobilization, the resulting catalysts show a high chemo- and stereo selectivity in the hydrogenation of C–C triple bonds. Systematic investigations of the preparation parameters indicate that the hydrolysis pH, the PVP amount and chainlength as well as the colloid aging time are of major importance for catalytic performance.     

Genetic mediation in the relationship of education to cognitive function in older people.

We used data from 136 monozygotic and 125 dizygotic human, male twin pairs (M age?=?64 years, range?=?59 to 70 years) to test whether the previously observed association (r?=?.30, p?     

Skyline-Based Registration of 3D Laser Scans

Acquisition and registration of terrestrial 3D laser scans is a fundamental task in mapping and modeling of cities in three dimensions. To automate this task marker-free registration methods are required. Based on the existence of skyline features,this paper proposes a novel method. The skyline features are extracted from panoramic 3D scans and encoded as strings enabling the use of string matching for merging the scans. Initial results of the proposed method in the old city center of Bremen are pre-sented.     

Tailor-made porous solid foods

A method of controlling the porosity of cellular solid foods and its dependence on solids content were investigated. Freeze-dehydration of cold-set alginate gels was used to produce tailor-made porous solids. Gels were composed of sodium alginate, corn starch, oil and other additives necessary to induce gelation. Porosity values were derived from particle and bulk densities utilizing a helium pycnometer and a volumetric displacement method. To achieve a wider range of porosities, the gels were immersed in sucrose solutions of 10 to 60 8Bx. Gel porosity after drying decreased from 0.85 to 0.42 and 0.07 after immersion in the 30 and 60 8Bx solution for 183 and 158 h, respectively. Similarly, after immersing gels containing an additional 5% soy oil, porosity decreased to 0.36 and 0.04 after 165 and 158 h, in 30 and 60 8Bx solution, respectively. Preparation and formulation play a significant role in porosity, and they can both be utilized to control its value within the range 0.85–0.04. SEM micrographs revealed changes in the original cellular solid, characterized by numerous large void spaces, to a denser and more uniform appearance of the specimen after immersion in the 60 8Bx sucrose solution. The dry gel system with controlled porosity provides a novel tool for the production of tailor-made cellular-solid foods.     

Marc concentration of sugar beet (Beta vulgaris L) in relation to sucrose storage

Pulp as a feed stuff produced in the sugar factory is estimated by the marc concentration in sugar beet, which consists of the insoluble cell wall compounds. To identify factors affecting level and development of marc concentration during the growing season, several field trials and pot experiments were carried out in 2000, 2001 and 2002. The results show that marc concentration decreased until 100 days after sowing, but then did not change markedly until October, when it ranged between 34 and 45 g kg^?1 beet. Marc concentration was affected more by site and variety than by year. Differences in marc concentration were already established very early in the season (65 days after sowing). This was attributed to the formation of cambial rings and parenchyma cells in the root during this period, which determine sucrose storage. There was a positive correlation between marc and dry matter, sucrose and betaine, but a negative correlation to root yield and amino N. Marc concentration was about 10% lower than reported in the past, which is supposed to be due to a change in the optimal cell volume for sucrose storage and the cell wall thickness of new sugar beet varieties. Copyright © 2004 Society of Chemical Industry     

Berry seed press residues and their valuable ingredients with special regard to black currant seed press residues

Berry seeds are distinguished by longevity though clear scientific appraisals cannot be made. Besides a hard seed coat other protecting substances are presumed in the seeds. Commonly the seeds are utilized as a source of oils. After pressing, there is a residue left that is still rich in bioactive ingredients. This paper gives an overview of the health-beneficial ingredients remaining in the residue of various berry seeds (bilberry, cranberry, rose hip, strawberry, elder, and black currant) with special focus on black currant. The fatty acid distribution and the content of fat, tocopherols and tocotrienols, phytosterols, carotenoids, vitamin C, fibre, protein, amino acids, dry matter, ashes, minerals, total phenols (gallic acid equivalent) and antioxidant capacity (TEAC) were determined. The investigation of berry seed press residues revealed that the total phenols and tocopherols were quantitatively the most important features of this material but there were significant differences between batches and cultures.