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111.
Kaisa Linderborg Oskar LaaksonenHeikki Kallio Baoru Yang 《Food research international (Ottawa, Ont.)》2011,44(7):2027-2033
Alpine bearberry (Arctostaphylos alpina L.) is a special circumpolar edible berry primarily used for household purposes but with greater potential in commercial applications than utilized thus far. In this study, the flavonoids of alpine bearberry were investigated with HPLC-DAD and HPLC-MS, and the sugars and fruit acids as trimethylsilyl derivates with GC-FID. The most abundant anthocyanin was cyanidin-3-O-galactoside accounting for over 95% of the anthocyanins. Eight other anthocyanins existed in trace amounts only, the richest of them being cyanidin-3-O-arabinoside and cyanidin-3-O-glucoside. Cyanidin accounted for over 99% of the anthocyanin aglycones. All the flavonols identified were glycosides of quercetin. Majority of the sugars were glucose and fructose while the most abundant fruit acid was quinic acid. The unique anthocyanin composition of alpine bearberry encourages advanced use of the berry as a food ingredient in private households and in industrial applications. In addition, it serves as a unique reference material for research purposes. 相似文献
112.
Kalle Arve Hannes Kannisto Hanna Härelind Ingelsten Kari Eränen Magnus Skoglundh Dmitry Yu. Murzin 《Catalysis Letters》2011,141(5):665-669
Abstract
Silver particle size and dispersion on a Ag/Al2O3 for HC-SCR were examined by means of chemisorption and TEM. Experimental results showed that determination of the accurate mean particle size (mps) is challenging and that the both applied methods have specific characteristics increasing the inaccuracy in the results which has to be taken into account in evaluation of catalytic activity. The results from TEM imaging were found to depend highly on the mode in which the surface was scanned (bright field versus dark field). Generally the point resolution was higher in dark field but the obtained mps did not increased along with the increasing silver loading. The main limitation with the O2-chemisorption was related to the choice of the stoichiometric factor between the adsorbent and silver atoms. However, together these techniques support each other and help to give a more realistic picture of the mean silver particle size, distribution and indications of the oxidation states on the alumina support. 相似文献113.
Marko Tarvainen Jukka‐Pekka Suomela Heikki Kallio 《European Journal of Lipid Science and Technology》2011,113(4):409-422
A fast ultra high performance liquid chromatography (UHPLC)–electrospray ionization (ESI)–mass spectrometric (MS) method was developed for simultaneous analysis of free fatty acids (FFAs), monoacylglycerols (MAG), diacylglycerols (DAG), triacylglycerols (TAG), and their oxidized equivalents. Effect of elevated column temperature was studied in order to optimize the chromatography of closely eluting peaks and to reduce high back pressure formed in UHPLC. The elevated temperature enabled high flow rate, better mass transfer, and therefore more narrow peaks and better separation of the analytes. The new method was applied to the analysis of total lipid extracts of lipolysis samples prepared by an artificial digestion model in order to investigate oxidized lipids and changes in their profiles in the chyme. Over 150 compounds were identified from the extracts. The UHPLC–ESI–MS method was proved to be fast, highly selective, and sensitive. Compared to a previously used high performance LC–ESI–MS method, the new UHPLC–ESI–MS method was over five times faster and consumed one tenth of the solvents while producing comparable quantitative results. Practical applications: Edible oils and fats contain mainly TAGs, the lipolysis of which produces FFAs and MAGs with minor DAG components. These compounds are susceptible to oxidation in the stomach, and therefore the analysis of the oxidation products is important. Fast determination of FFAs and acylglycerols is also important in quality control of biodiesel. Our new method enables accurate and sensitive determination of different molecular species present in digested and processed samples with minimal sample preparation requirements. In this respect, the new method is applicable to large scale and fast screening of biological samples for lipidomic and metabolomic studies. 相似文献
114.
A three-dimensional model has been developed for the free-breathing direct methanol fuel cell (DMFC) assuming steady-state isothermal and single-phase conditions. Especially the MeOH crossover phenomenon is investigated and the model validations are done using previous cathodic current distribution measurements. A free convection of air is modelled in the cathode channels and diffusion and convection of liquid (anode) and gaseous species (cathode) in the porous transport layers. The MeOH flow in the membrane is described with diffusion and protonic drag. The parameter ψ in the model describes the MeOH oxidation rate at the cathode and it is fitted according to the measured current distributions. The model describes the behaviour of the free-breathing DMFC, when different operating parameters such as cell temperature, MeOH concentration and flow rate are varied in a wide range. The model also predicts the existence of the experimentally observed electrolytic domains, i.e. local regions of negative current densities. Altogether, the developed model is in reasonable agreement with both the measured current distributions and polarization curves. The spatial information gained of mass transfer phenomena inside the DMFC is valuable for the optimization of the DMFC operating parameters. 相似文献
115.
Sigfridsson K Lundqvist A Strimfors M 《Drug development and industrial pharmacy》2011,37(9):1036-1042
In Sigfridsson et al. (2011, Drug Dev Ind Pharm, 37:243-251), there was no difference in plasma concentration of BA99 when administering the drug as nanosuspension or microsuspension and analyzing the blood samples by liquid chromatography-mass spectrometry. This was related to the dissolved amount of drug in the gastric tract, which was high enough to support fast absorption when the drug reached the small intestine. One single physicochemical property (pK(a), about 3 for BA99) abolished the benefit of small particles. These results were further confirmed in the present study, where a proton pump inhibitor, AZD0865, was used to elevate the gastric pH and then drastically decreased the gastric solubility. In this way, BA99 could be considered as a model compound for a neutral substance. By increasing the gastric pH to 5-6 and 8-9, respectively, in rats, the plasma concentrations of BA99, after administering nanosuspensions, were unchanged compared with untreated (i.e. no AZD0865) animals. For microsuspensions of the test compound, on the other hand, the exposure of BA99 was 2- to 3-fold lower than for nanosuspensions at both pHs. Moreover, the blood concentrations of BA99 administered as microsuspension were also 2- to 3-fold lower compared with untreated (no AZD0865) individuals receiving both nanoparticles and microparticles of BA99. Obviously, for neutral compounds, with similar physicochemical properties as the present compound, size reduction will be crucial for increased plasma exposure. For basic compounds, with similar physicochemical properties as the present compound, the crucial step for absorption is the dissolution and solubility in the gastric tract. 相似文献
116.
Based on the Eulerian–Eulerian two-fluid continuum approach, an improved unified second-order-moment two-phase turbulence model combining with the kinetic theory of particle collision frictional stress model is developed to simulate the dense gas–particle flows in downer, where the effective coefficient of restitution is incorporated into the particle–particle collision. The interaction term between gas and particle turbulence is fully taken into account by the transport equation of two-phase stress correlation. Hydrodynamics of high density particle flow, measured by Wang et al. [27] are predicted and the simulated results are in good agreement with experimental data. On the conditions of considering the realistic energy dissipation due to frictional stress, particle concentration and particle axial averaged velocity are closely the measured and they are better than without frictional stress model. Furthermore, the particle Reynolds stress is redistributed and the particle temperature is reduced. Effect of frictional stress leads to increase obviously the collision frequency at the outlet and inlet regions and the magnitude of frequency of particle collisions is 102. 相似文献
117.
Rita Lavikka Johanna Kallio Thomas Casey Miimu Airaksinen 《Construction Management & Economics》2013,31(11):635-650
Decision-makers in the architecture, engineering and construction (AEC) industry lack knowledge about the implementation of digitalization to generate value. We applied a scenario planning method developed by Schoemaker and Mavaddat to provide decision-makers with information for using digital data and technologies to create value for customers. We aim to theoretically understand how the scenario planning process helps AEC decision-makers to make sense of the future. Our findings show that boundary spanners are needed for steering the discussions among industry actors towards shared knowledge about the technological, social, economic and political changes needed at the industry level to optimize the benefits of digitalization. Our findings also show that boundary spanners apply scenario figures as boundary objects to cross knowledge boundaries. Based on our findings, we theoretically conceptualize scenario planning as a boundary-spanning activity that enables AEC decision-makers from different fields to share tacit knowledge and to cross knowledge boundaries. The practical implication is that scenario planning provides a method for AEC decision-makers to make sense of the changes needed to realize the preferred future for the industry. 相似文献
118.
Riitta Partanen Mikko Ahro Mari Hakala Heikki Kallio Pirkko Forssell 《European Food Research and Technology》2002,214(3):242-247
Microencapsulation of supercritical CO2 extracted caraway fruit oil was investigated. Encapsulation was carried out by molecular inclusion with #-cyclodextrin, by spray-drying with maltodextrin and by spray-drying with a starch derivative. Carvone, one of the two main constituents of caraway essential oil, was efficiently complexed with #-cyclodextrin. Only half of the other major constituent, limonene, was complexed. The inclusion complex seemed to protect volatile substances more efficiently during storage, whereas microcapsules with modified starches as wall material were more heat tolerant. During rapid heating, the #-cyclodextrin microcapsules protected the volatile substances from evaporation up to 100 °C and HiCap microcapsules protected them up to 140 °C, while the protection properties of the maltodextrin microcapsules seemed to depend on the encapsulated molecules (160 °C for limonene and 120 °C for carvone). 相似文献
119.
Flaxseed in Breadmaking: Effects on Sensory Quality, Aging, and Composition of Bakery Products 总被引:1,自引:0,他引:1
Terhi A. Pohjanheimo Mari A. Hakala Raija L. Tahvonen Seppo J. Salminen Heikki P. Kallio 《Journal of food science》2006,71(4):S343-S348
ABSTRACT: This paper describes the effect of flaxseed on two bread formulations. The quality of bread rolls—containing flaxseed—and the quality of cinnamon rolls—containing flaxseed and flaxseed oil—is determined by sensory evaluation (texture, odor, and flavor), instrumental texture measurement and chemical analysis (fatty acids, fiber, secoisolarisiresinol diglycoside, and cadmium). Bread aging is monitored by measuring sensory attributes during storage. The results indicate that the flaxseed rolls retain moisture and softness more efficiently than the control rolls that do not contain flaxseed. No off-odors were detected during the storage period from 0 to 6 d at room temperature (+22 °C), although flaxseed rolls and cinnamon rolls were discovered to be high in unsaturated fats. The major fatty acid in both bakery samples that contained flaxseed was α-linolenic acid. The flaxseed rolls were also high in fiber. Therefore, from a nutritional viewpoint flaxseed shows beneficial properties in breadmaking. It has a positive impact on the texture parameters during storage as well as on the nutritional composition, for example, the content of fiber and unsaturated fats. 相似文献
120.
CM Forsblom T Sane PH Groop KJ T?tterman M Kallio C Saloranta L Laasonen P Summanen M Lep?ntalo L Laatikainen E Matikainen AM Teppo S Koskimies L Groop 《Canadian Metallurgical Quarterly》1998,41(11):1253-1262
To test the hypothesis that interaction between genetic, immunological, clinical and metabolic risk factors influences the outcome of Type II (non-insulin-dependent) diabetes mellitus, we examined which of the above factors present at baseline were associated with mortality in 134 Type II diabetic patients followed for 9 years. Thirty-eight patients (29%) died during the follow-up period; the majority of whom (68%) died from cardiovascular disease. At baseline, the deceased patients had higher HbA1c values (p = 0.002), higher LDL-triglycerides (p = 0.007), lower HDL-cholesterol (p = 0.007), higher non-esterified fatty acid (NEFA) concentrations (p = 0.014), and higher albumin excretion rate (p < 0.0001) than the patients who survived. In addition, the frequency of HLA-DR4 (21 vs 39%, p = 0.048) and of parietal cell antibodies (5 vs 14%, p = 0.016) were decreased in the deceased as compared to the living patients. Patients who died during follow-up also had more retinopathy (42 vs 16%, p = 0.002), neuropathy (57 vs 23%, p < 0.001), microalbuminuria (45 vs 6%, p < 0.0001), coronary heart disease (50 vs 13%, p < 0.0001), and peripheral vascular disease (27 vs 9%, p = 0.005) at baseline than patients who survived. In a multiple logistic regression analysis macroangiopathy (p = 0.004), neuropathy (p = 0.007), HbA1c (p = 0.018) and albumin excretion rate (p = 0.016) were independent risk factors for death. In patients free of cardiovascular disease at baseline, conventional risk factors such as LDL-cholesterol (p = 0.005) and age (p = 0.003) were associated with subsequent development of cardiovascular disease. In conclusion, in addition to coexisting macroangiopathy, increased albumin excretion rate, poor glycaemic control and neuropathy are risk factors for cardiovascular mortality in patients with Type II diabetes. The presence of HLA-DR4 and signs of autoimmunity may be associated with decreased risk of cardiovascular disease. 相似文献