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61.
Ozgur OzayErk Inger Nahit AktasNurettin Sahiner 《International Journal of Hydrogen Energy》2011,36(14):8209-8216
In situ Co, Cu and Ni nanoparticles were synthesized by chemical reduction of the absorbed Co (II), Cu (II) and Ni (II) ions inside hydrogel networks prepared from 2-acrylamido-2-methyl-1-propansulfonic acid (AMPS) and were used as a catalyst system in the generation of hydrogen in hydrolysis of ammonia borane (AB). Several parameters affecting the hydrolysis reaction such as the type of the metal, the amount of catalyst, the initial concentration of AB, and temperature, were investigated. The activation energy values in the hydrolysis reaction of AB solution in the presence p(AMPS)-Co, p(AMPS)-Cu and p(AMPS)-Ni catalyst systems were calculated as Ea = 47.7 kJ mol−1, 48.8 kJ mol−1 and 52.8 kJ mol−1, respectively. Thus, the catalytic activity of the metal nanoparticles prepared inside the same hydrogel matrix was found to be Ni < Cu < Co. 相似文献
62.
Heft’s functional taxonomy for children’s outdoor environment based on the concept of affordances was applied and investigated in a Danish preschool context. Affordances here refer to the meaningful action possibilities of the environment. Two groups of children (3–6 years) enrolled in preschool were observed during times for ‘free play’ in their usual outdoor settings: traditional playground and forest (12 visits, respectively). Modified classes of outdoor features are suggested along with new practical class names: open ground, sloping terrain, shielded places, rigid fixtures, moving fixtures, loose objects, loose material, water, creatures and fire. Each class is specified by distinctive and attractive key activities found by observation. Examining each class indicated that important characteristics apart from availability were variation, sizes and change. The concept of affordances emphasises the ongoing user–environment–activity relationship important for planning with children in mind, but clarification is needed when using the term. 相似文献
63.
Dorota Kostrzewa Agnieszka Dobrzyńska–Inger Edward Rój Karolina Grzęda Kazimierz Kozłowski 《Journal of the Institute of Brewing》2016,122(3):493-499
An isomerization process of the α‐acids contained in hop extract (with magnesium oxide, potassium hydroxide and magnesium peroxide as catalysts at ambient temperature) was carried out. The influence of two factors (the amount of applied catalyst and the isomerization time) was studied. Ultra‐high performance liquid chromatography was used for the evaluation of the isomerization process. The best results were obtained with magnesium oxide. In this case, the influence of the operating variables on the isomerization process and optimal process parameters were determined using statistical methods. The isomerization method described above could be carried out with high efficiency without heating and could be easily adopted and applied on an industrial scale. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
64.
Janna Cropotova Revilija Mozuraityte Inger B. Standal Magnhild S. Grøvlen Turid Rustad 《International Journal of Food Science & Technology》2019,54(6):2228-2235
Changes in quality characteristics in relation to protease activity and protein oxidation in chilled, superchilled and frozen mackerel fillets during storage were studied. The solubility of sarcoplasmic proteins was quite stable in mackerel samples for all storage experiments, whereas the solubility of myofibrillar proteins decreased in both superchilled and frozen samples. A significant correlation (r = 0.983, P < 0.05) between the increased activity of cathepsin B+L in chilled fillets and softening of the fish flesh during storage was revealed. Contrary with chilled samples, the texture of superchilled mackerel fillets became tougher along the storage period, which can be explained by a higher rate of myofibrillar oxidation (r = 0.940, P < 0.05). The hardness and drip loss decreased slightly at the end of frozen storage. Superchilling preserved the quality of mackerel fillets with the least side effects in relation to protein solubility, drip loss and softening of the fish tissue as compared to chilled and frozen storage. 相似文献
65.
Polymeric microgels were prepared from dextran (Dex) by crosslinking linear natural polymer dextran with divinyl sulfone (DVS) with a surfactant-free emulsion technique resulting in high gravimetric yield of 78.5 ± 5.3% with wide size distribution. Dex microgels were chemically modified, and then used as catalyst in the methanolysis of NaBH4 to produce H2. The chemical modification of Dex microgel was done on epichlorohydrin (ECH)-reacted Dex microgels with ethylenediamine (EDA), diethylenetriamine (DETA), and triethylenetetraamine (TETA) in dimethylformamide (DMF) at 90°C for 12 hours. The modified dextran-TETA microgels were protonated using treatment with hydrochloric acid (HCl) and m-Dex microgels-TETA-HCl was found to be a very efficient catalyst for methanolysis of NaBH4 to produce H2. The effects of reaction temperature and NaBH4 concentration on H2 generation rates were investigated and m-Dex microgels-TETA-HCl catalyst possessed excellent catalytic performances with 100% conversion and 80% activity at end of 10 consecutive uses and was highly re-generatable with simple HCl treatment. Interestingly, m-Dex microgels-TETA-HCl catalyst can catalyze NaBH4 methanolysis reaction in a mild temperature range 0 to 35°C with Ea value of 30.72 kJ/mol and in subzero temperature range, −20 to 0°C with Ea value of 32.87 kJ/mol, which is comparable with many catalysts reported in the literature. 相似文献
66.
Pallesen St?le; Hilde Inger Nordhus; Havik Odd E.; Nielsen Geir H?stmark 《Canadian Metallurgical Quarterly》2001,32(2):115
Insomnia is characterized by problems initiating and maintaining sleep—problems that often go unrecognized by psychotherapists as well as physicians. This article addresses central questions related to the diagnosis, assessment, and treatment of this problem. Differential diagnosis is focused upon as well as the comorbidity with psychiatric and organic disorders. The Assessment of Insomnia section covers different subjective measures of sleep: sleep diaries, sleep questionnaires, and sleep interview. Additionally, central objective sleep measures are included. In the Treatment of Insomnia section, the 6 most common behavioral interventions are presented together with the most current pharmacological approaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
68.
Witt MJ Sheehan EV Bearhop S Broderick AC Conley DC Cotterell SP Crow E Grecian WJ Halsband C Hodgson DJ Hosegood P Inger R Miller PI Sims DW Thompson RC Vanstaen K Votier SC Attrill MJ Godley BJ 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2012,370(1959):502-529
Marine renewable energy installations harnessing energy from wind, wave and tidal resources are likely to become a large part of the future energy mix worldwide. The potential to gather energy from waves has recently seen increasing interest, with pilot developments in several nations. Although technology to harness wave energy lags behind that of wind and tidal generation, it has the potential to contribute significantly to energy production. As wave energy technology matures and becomes more widespread, it is likely to result in further transformation of our coastal seas. Such changes are accompanied by uncertainty regarding their impacts on biodiversity. To date, impacts have not been assessed, as wave energy converters have yet to be fully developed. Therefore, there is a pressing need to build a framework of understanding regarding the potential impacts of these technologies, underpinned by methodologies that are transferable and scalable across sites to facilitate formal meta-analysis. We first review the potential positive and negative effects of wave energy generation, and then, with specific reference to our work at the Wave Hub (a wave energy test site in southwest England, UK), we set out the methodological approaches needed to assess possible effects of wave energy on biodiversity. We highlight the need for national and international research clusters to accelerate the implementation of wave energy, within a coherent understanding of potential effects-both positive and negative. 相似文献
69.
Inger Lindin Yimingjiang Wuxiuer Aina Westrheim Ravna Ugo Moens Ingebrigt Sylte 《International journal of molecular sciences》2014,15(3):4878-4902
The mitogen-activated protein kinase-activated protein kinase MK5 is a substrate of the mitogen-activated protein kinases p38, ERK3 and ERK4. Cell culture and animal studies have demonstrated that MK5 is involved in tumour suppression and promotion, embryogenesis, anxiety, cell motility and cell cycle regulation. In the present study, homology models of MK5 were used for molecular dynamics (MD) simulations of: (1) MK5 alone; (2) MK5 in complex with an inhibitor; and (3) MK5 in complex with the interaction partner p38α. The calculations showed that the inhibitor occupied the active site and disrupted the intramolecular network of amino acids. However, intramolecular interactions consistent with an inactive protein kinase fold were not formed. MD with p38α showed that not only the p38 docking region, but also amino acids in the activation segment, αH helix, P-loop, regulatory phosphorylation region and the C-terminal of MK5 may be involved in forming a very stable MK5-p38α complex, and that p38α binding decreases the residual fluctuation of the MK5 model. Electrostatic Potential Surface (EPS) calculations of MK5 and p38α showed that electrostatic interactions are important for recognition and binding. 相似文献
70.
Inger B. Standal David E. Axelson Marit Aursand 《Journal of the American Oil Chemists' Society》2009,86(5):401-407
The aim of this study was to use 13C-nuclear magnetic resonance (NMR) regiospecific analyses of triacylglycerols to distinguish fish oils from different fish
species for authentication purposes. 13C-NMR data of muscle lipids from Atlantic salmon (Salmo salar L.), mackerel (Scomber scombrus) and herring (Clupea harengus) were obtained, and the distribution of omega-3 polyunsaturated fatty acids between the sn-1,3 and sn-2 glycerol chains calculated
from the carbonyl region. The results show that there were significant differences in the sn-2 position specificity of the
fatty acids 22:6n-3, 20:5n-3 and 18:4n-3 among the species investigated. The most pronounced difference was that herring had
a higher proportion of its 22:6n-3 in the sn-2 position compared to the two other species. Principal component analysis of
data points in the carbonyl-region showed that there were also differences in the level and regiospecific distribution of
monounsaturated/saturated fatty acids, which made it possible to distinguish oils of these three species solely from the carbonyl
region of 13C-NMR spectra. 相似文献