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51.
Kimmo Lahtinen Kalle Nättinen Jari Vartiainen 《Polymer-Plastics Technology and Engineering》2013,52(5):561-569
In this study, the effect of heat treatment on barrier and functionality of polyolefin-coated papers was investigated. The aim was to find the optimal improvements on barrier without losing the applicability of the materials due to physical damages. The results of the study proved considerable improvement in barrier characteristics of the structures. Both water vapor and oxygen transmission rates of LDPE-coatings decreased linearly following the set-temperature until 200°C. At this point, the treatment caused a continuing decrease in oxygen transmission achieving 10 × lower transmission levels than the untreated structure, whereas moisture transport faced corresponding but lower increase. This was considered to be caused by the difference in diameter of the H2O and O2 molecules; the smaller water molecules are able to penetrate between spherulites, whose size increased due to higher treatment temperature followed by cooling. 相似文献
52.
Sugars and acids of strawberry varieties 总被引:4,自引:0,他引:4
H. Kallio M. Hakala A-M. Pelkkikangas A. Lapveteläinen 《European Food Research and Technology》2000,212(1):81-85
The sugar and acid compositions of six strawberry (Fragaria×ananassa Duch.) varieties from 1997 and 1998, grown in different conditions, 26 samples in all, were investigated by GC as trimethylsilyl derivatives. The major sugars were glucose (1.89–4.52?g/100?ml), fructose (2.14–4.14?g/100?ml) and sucrose (0.90–3.87?g/100?ml), the major acids being citric (0.73–1.58?g/100?ml) and malic (0.22–0.69?g/100?ml). Total sugar content (glucose+fructose+sucrose) varied from 5.35?g/100?ml to 10.96?g/100?ml in accordance with soluble solids (°Brix). The correlation between them showed a linear regression y=0.873x-0.420, the percentage of determination of the regression model being 82.1%. Among one variety only, ‘Senga Sengana’, the percentage of the model was 86.9%. No significant differences were found between the strawberries from conventional versus those from organic farms. Contents of sugars and soluble solids were lower in varieties ‘Jonsok’ and ‘Honeoye’ than in ‘Korona’, ‘Bounty’ and ‘Polka’. The concentrations of malic acid were significantly higher in Senga Sengana, Jonsok and Bounty than in other varieties. 相似文献
53.
Quantitation of acyl migration during lipase-catalyzed acidolysis, and of the regioisomers of structured triacylglycerols formed 总被引:1,自引:0,他引:1
Huiling Mu Juha-Pekka Kurvinen Heikki Kallio Xuebing Xu Carl-Erik Høy 《Journal of the American Oil Chemists' Society》2001,78(9):959-964
Various MLM-type (M, medium-chain fatty acids; L, long-chain fatty acids) structured triacylglycerols were produced in pilot-
or small-scale packed-bed reactors by lipasecatalyzed acidolysis. The incorporation and acyl migration of octanoic acid were
measured by gas chromatography and Grignard degradation, and ranged from 39.0 to 48.7% and 0.6 to 9.3%, respectively. Quantitation
of triacylglycerol molecular species was performed by ammonia negative ion chemical ionization (NICI) mass spectrometry (MS).
The proportion of ACN (acyl carbon number) 34 species that contained one C18 fatty acid and two C8∶0′ in samples analyzed, varied from 12.5 to 23.2%. The selected regioisomers MLM and MML within the ACN 34 species group were
quantified by NICI tandem MS (MS/MS) and were in the range of 97.1 to 98.4% and 1.6 to 2.9%, respectively. There was no correlation
between the level of acyl migration during lipase-catalyzed esterification and the level of regioisomers of the selected MLM-type
triacylglycerols in the structured lipid samples. 相似文献
54.
A semi-operative approach to lake water quality retrieval from remote sensing data 总被引:21,自引:0,他引:21
Pulliainen J Kallio K Eloheimo K Koponen S Servomaa H Hannonen T Tauriainen S Hallikainen M 《The Science of the total environment》2001,268(1-3):79-93
A semi-operative approach to retrieve chlorophyll-a concentration from airborne/spaceborne spectrometer observations has been developed and tested using the airborne imaging spectrometer (AISA) data from 11 lakes located in southern Finland. The retrieval approach is empirical and requires nearly simultaneous in situ training data on water quality for the determination of regression coefficients. However, the training data does not have to be collected from every lake under investigation. Instead, the results obtained indicate that reliable estimates on the level of chlorophyll-a (chl-a) for an individual lake can be achieved without employing in situ data representing this specific lake. This enables the estimation of water quality from remotely sensed data for numerous lakes with the aid of reference data only for a few selected lakes representing the region under investigation. In addition, it is shown that the remotely sensed spectrum shape characteristics are highly affected by the trophic and humic state of the lake water. 相似文献
55.
56.
O Sj?vall E Honkanen H Kallio K Latva-Kala A M Sj?berg 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1990,191(3):181-183
Chemical changes due to gamma-irradiation were investigated in 11 pure aroma compounds typically found in spices. Samples were irradiated with doses of 0, 10, and 50 kGy. The irradiation source was 60Co. Irradiated samples and unirradiated controls were analyzed by gas chromatography alone and coupled with mass spectrometry. Significant changes due to the irradiation occurred only in (+/-)-linalool and alpha-terpineol, which are typical components of, for example, coriander and bay leaf. Their total amounts decreased by about 4-13% and some minor peaks increased as a result of irradiation. However, different results may be obtained when the spices themselves are irradiated. 相似文献
57.
58.
Analysis of butter fat triacylglycerols by supercritical fluid chromatography/electron impact mass spectrometry 总被引:2,自引:0,他引:2
Triacylglycerols (TAGs) from butter fat isolated by solvent extraction were analyzed by use of a capillary column supercritical fluid chromatograph (SFC) combined with a flame ionization detector or a double focusing mass spectrometer. The chromatographic separation was achieved by using a dimethyldiphenylpolysiloxane phase (DB-5) to bundle up the TAGs with the same carbon number. The ratio of TAGs with varying degree of unsaturation in each SFC peak was determined by using the selected ion monitoring of the molecular ions with electron impact mode. The discrimination between the fatty acids at the position sn-2 and positions sn-1/3 in a triacylglycerol molecule was demonstrated by monitoring the ions [M - RCO2CH2]+ from reference compounds. 相似文献
59.
To assess the value of adjunctive intravenous dexamethasone (DXM) and oral glycerol (GLY) for the treatment of bacteriologically proved bacterial meningitis, 122 infants and children with bacterial meningitis were randomly assigned to receive DXM intravenously (n = 32), GLY orally (n = 30), DXM plus GLY (n = 34) or neither (n = 26) of these drugs. All patients were treated with the same antimicrobial agent, ceftriaxone. The patients were followed neurologically for as long as 6 months. A thorough hearing evaluation was performed routinely 2 months or more after discharge from hospital. Overall 4 (7%) of the GLY-treated patients, compared with 11 (19%) of those not given GLY, developed audiologic or neurologic sequelae (P = 0.052), the relative risk of sequelae being 2.94 (95% confidence interval, 0.99 to 8.72). The patients who had received GLY showed less severe or profound bilateral hearing impairment than those not given GLY (0 vs. 7%, P = 0.049), and none of them had other neurologic abnormalities 3 or 6 months after discharge, compared with 5 (9%) of those not treated with GLY (P = 0.024). The DXM recipients showed only a tendency to less severe hearing impairment than those not given DXM. In conclusion oral GLY prevented neurologic sequelae in infants and children with bacterial meningitis more effectively than intravenous DXM. 相似文献
60.
H Glimm K Flügge D M?best VM Hofmann J Postmus R Henschler W Lange J Finke HP Kiem G Schulz F Rosenthal R Mertelsmann C von Kalle 《Canadian Metallurgical Quarterly》1998,9(6):771-778
BACKGROUND: Home training in self-lowering of blood pressure using continuous blood pressure feedback has not previously been reported. Enhancement of laboratory-learned skills was hypothesized on the basis of outcomes from other intellectual, emotional and physical endeavours. OBJECTIVE: To examine the supplementary effect of home blood pressure biofeedback training. DESIGN: Thirty unmedicated, mild hypertensives participated in a randomized, double-blinded, modified contingency placebo-controlled study. METHOD: After suitable screening and baseline blood pressure measurements subjects undertook eight laboratory biofeedback sessions and then 12 home training sessions over 4 weeks using continuous finger blood pressure monitoring. RESULTS: In the laboratory those being administered active therapy (n=16) lowered systolic pressures by 5 +/- 5.4 mmHg compared with a lowering of 4 +/- 4.2 mmHg with placebo (NS). During the fourth week at home lowering for the active group (11 +/- 8 mmHg) was greater than that with placebo (4 +/- 6.2 mmHg, P=0.017). Arm-cuff blood pressures were not statistically different for groups and with time but that of the active group was lower by 9 +/- 15.4/7 +/- 10.2 mmHg, which is a clinically relevant change, after home biofeedback. CONCLUSIONS: The efficacy of self-lowering of systolic blood pressure in mild hypertensives by continuous feedback was enhanced by 6 mmHg with 4 weeks of practice at home. Standard arm-cuff blood pressure was reduced by a clinically relevant amount. The home environment proved cost effective for this 'high-tech' approach. 相似文献