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361.
Reetta Karinen Sanna Airaksinen Päivi Kiviranta Kari Keskinen Juha Linnekoski Petri Uusi-Kyyny A. Outi I. Krause 《Topics in Catalysis》2011,54(16-18):1206-1212
Microreactors with chromia/alumina catalyst were investigated in isobutane dehydrogenation. Chromia was deposited in the reactor by atomic layer deposition (ALD). Conversion increased with chromium content in the reactor and isobutene selectivity was higher than with conventional powder catalyst. Thermal reactions were negligible making microreactors attractive for measuring kinetic data. 相似文献
362.
Kalle Nättinen Juha Nikkola Hannu Minkkinen Pirjo Heikkilä Juho Lavonen Mikko Tuominen 《Journal of Coatings Technology and Research》2011,8(2):237-245
Plasma deposition equipment was developed and installed at a pilot extrusion coating line for reel-to-reel substrates. Hexamethyldisiloxane
was used as a siloxane precursor for the atmospheric plasma deposition of siloxane coatings on substrates of three different
categories: paper, polyethylene-coated paper, and textile materials (woven cotton fabric and polypropylene nonwoven). SEM,
H2O contact angle measurements, heat sealability, and water vapor barrier measurements were carried out to characterize the
composition and surface structure of the samples. The potential of the method and the equipment was shown by the coatings,
ranging to micrometer scale. With selected samples, hydrophobic coating was shown to form at speeds up to 100 m/min. 相似文献
363.
364.
Satu Tamminen Ilmari Juutilainen Juha Röning 《Expert systems with applications》2013,40(11):4577-4584
The purpose of this study was to develop methods for exceedance probability estimation in the case of highly scattered measurement sets. The situation may occur when product quality is verified with several test samples, and thus, traditional point prediction based modelling methods are not sufficient.Density forecasting methods are needed when not only the mean but also the deviance and the distribution shape of the response depend on the explanatory variables. Furthermore, with probability predictors, the ranking methods for the model selection should be chosen carefully, when models trained with different methods are compared.In this article, the impact toughness of the steel products was modelled. The rejection probability in Charpy-V quality test was predicted with mean and deviation models, distribution shape model and quantile regression model. The proposed methods were employed in two steel manufacturing applications with different distributional properties. 相似文献
365.
Antti A Mero Tuomo Ojala Juha J Hulmi Risto Puurtinen Tuomo AM Karila Timo Seppälä 《Journal of the International Society of Sports Nutrition》2010,7(1):1-8
Background
The effect of moderate dehydration and consequent fluid replenishment on short-duration maximal treadmill performance was studied in eight healthy, fit (VO2max = 49.7 ± 8.7 mL kg-1 min-1) males aged 28 ± 7.5 yrs.Methods
The study involved a within subject, blinded, crossover, placebo design. Initially, all subjects performed a baseline exercise test using an individualized treadmill protocol structured to induce exhaustion in 7 to 10 min. On each of the three subsequent testing days, the subjects exercised at 70-75% VO2max for 60 min at 29-33°C, resulting in a dehydration weight loss of 1.8-2.1% body weight. After 60 min of rest and recovery at 22 C, subjects performed the same treadmill test to voluntary exhaustion, which resulted in a small reduction in VO2max and a decline in treadmill performance by 3% relative to the baseline results. Following another 60 min rest and recovery, subjects ingested the same amount of fluid lost in the form of one of three lemon-flavored, randomly assigned commercial drinks, namely Crystal Light (placebo control), Gatorade® and Rehydrate Electrolyte Replacement Drink, and then repeated the treadmill test to voluntary exhaustion.Results
VO2max returned to baseline levels with Rehydrate, while there was only a slight improvement with Gatorade and Crystal Light. There were no changes in heart rate or ventilation with all three different replacement drinks. Relative to the dehydrated state, a 6.5% decrease in treadmill performance time occurred with Crystal Light, while replenishment with Gatorade, which contains fructose, glucose, sodium and potassium, resulted in a 2.1% decrease. In contrast, treatment with Rehydrate, which comprises fructose, glucose polymer, calcium, magnesium, sodium, potassium, amino acids, thiols and vitamins, resulted in a 7.3% increase in treadmill time relative to that of the dehydrated state.Conclusions
The results indicate that constituents other than water, simple transportable monosaccharides and sodium are important for maximal exercise performance and effective recovery associated with endurance exercise-induced dehydration. 相似文献366.
Maret Liiri Henry Hatakka Juha Kallas Juhani Aittamaa Ville Alopaeus 《Chemical Engineering Research and Design》2010
In this study a combination of computational fluid dynamics (CFD) and multiblock model is used for modelling crystal growth in a 100 dm3 suspension crystallizer equipped with two turbine impellers. Local hydrodynamics and crystal suspension densities were modelled using CFD. Simulation results were compared with experimental results to verify flow profile and slip velocities (Hatakka et al., 2008, 2009), and classification of crystals. Results from CFD simulations were then translated to a proper form and used as input data for the multiblock model. 相似文献
367.
This review discusses the developments in aerosol instrumentation that have led to the current vapor condensation based instruments capable of detecting sub-3?nm particles. We begin from selected reports prior to the year 1991, which have advanced the technology or understanding in condensation particle counting toward sub-3?nm sizes, and continue to more in depth review of the past efforts after 1991. We discuss how the developments in the calibration methods have progressed the development of particle counting techniques, and review briefly the sub-3?nm calibration experiments and cluster production methods used in calibration experiments. Based on these reviews, we identify several technological and scientific advances for the future to improve the accuracy, understanding, and technology of sub-3?nm particle counting.Copyright © 2019 American Association for Aerosol Research 相似文献
368.
Maoshuai He Sami Vasala Hua Jiang Maarit Karppinen Esko I. Kauppinen Marita Niemelä Juha Lehtonen 《Carbon》2012,50(12):4750-4754
A novel catalyst of cobalt supported by single crystal MgO was prepared by atomic layer deposition and used for carbon nanotube growth. With CO as carbon source, vertically-aligned carbon nanotubes with predominant double-walled (82%) were produced at 700 °C. Similar carbon nanotube array with a majority of single-walled tubes (62%) was produced at 900 °C using methane as the carbon source. Due to their high flexibility compared with multi-walled carbon nanotubes, the low-wall-number carbon nanotube array could form a 3-dimensional honeycomb-like network when being spread with acetone. 相似文献
369.
Miina Rautiainen Juha Suomalainen Pauline Stenberg Jouni Peltoniemi 《Remote sensing of environment》2007,110(3):332-343
The Arctic region is predicted to experience considerable climatic and environmental changes as the global atmospheric CO2 increases. Growing awareness of the role of tundra and taiga ecosystems and their transition zone in the climate change process has resulted in a recent increase in remote sensing studies focusing on the Arctic latitudes. Remote sensing of biophysical properties of the canopy layer in the forested part of the region is often, however, challenged by the dominating role of the understory in the spectral signal. In this paper, we examine the influence of understory vegetation on forest reflectance in the Arctic region of Finland during no-snow conditions. The study is based on SPOT HRVIR images, field goniospectrometry, 300 ground reference plots and a physically-based forest reflectance model (PARAS). The results indicate that lichen-dominated forest site types can be distinguished from sites dominated by dwarf shrubs. The paper also contains results from applying an analytical method for calculating photon recollision probability from canopy transmittance data for forest stands, and then using it to simulate the reflectance of the same stands. 相似文献
370.
Harri Hakala Pivi Liitti Katri Puukka Jari Peuralahti Kristiina Loman Jarkko Karvinen Pia Ollikka Alice Ylikoski Veli-Matti Mukkala Jari Hovinen 《Inorganic chemistry communications》2002,5(12):2511
A series of new stable, luminescent samarium(III) chelates were synthesized and their photophysical properties were measured. The iodoacetamido activated chelate coupled to a peptide was used in a caspase-3 assay. 相似文献