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41.
J?rg Brüggemann Jorma Kumpulainen 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1995,201(1):1-6
In representative samples of bread cereals and cereal products from the former Federal Republik of Germany (FRG) the status of 11 trace elements was analysed in 1989. It is demonstrated that the results are quite representative for the former FRG as compared with results published in the previous 15 years. The sampling technique for staple foods is explained. A number of certified standard reference materials were used to validate the analytical methods employed.
Spurenelementgehalte in Grundnahrungsmitteln der BundesrepublikI. Gehalte von 11 Spurenelementen
Zusammenfassung In repräsentativen Proben von Brotgetreide und Getreideprodukten aus der Bundesrepublik werden die Gehalte von 11 Spurenelementen für das Jahr 1989 analysiert. Es wird gezeigt, daß die Ergebnisse repräsentativ für die alte Bundesrepublik sind, wenn man sie mit den Ergebnissen aus den vergangenen 15 Jahren vergleicht. Die Probennahmetechnik für die Herstellung von Grundnahrungsmittelproben wird erklärt. Zertifizierte Standard-Referenz-Materialien wurden verwendet, um die Ergebnisse der Analysen abzusichern.相似文献
42.
Spreadsheet calculation is a powerful tool in simple administrative data processing. Formulae in spreadsheets have similar forms to expressions in traditional programming languages, but the implementation of control structures is totally different. This paper contains an analysis of 101 spreadsheets made and used in business and government. The analysis concerns general properties, such as cell contents and referencing, the role of input, output and computation, and the different ways iteration is implemented. Finally some effects of expertise are studied. The results show that less than half of the available functions are really used, only one cell in 25 contains computation, and iteration is implemented in at least four different ways. Formulae are found to differ in their contents from expressions of programming languages, as control structures are implemented differently in these systems. Summation with a constant skip is suggested to be included in the set of functions of spreadsheet calculation. 相似文献
43.
Anneli Niemi Eija-Riitta Venäläinen Timo Hirvi Jorma Hirn Eeva Karppanen 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1991,192(5):427-429
Summary The lead, cadmium and mercury concentrations in muscle, liver and kidney from Finnish pigs and cattle were determined. The average wet weight lead concentrations in pig muscle, liver and kidney were 15 g/kg, 38 g/kg and 40 g/kg, respectively. The corresponding concentrations for cattle were 13 g/kg, 57 g/kg and 110 g/kg. The average wet weight cadmium concentrations were 1.5 g/kg, 28 g/kg and 170 g/kg (pigs) and 1.3 g/kg, 61 g/kg and 350 g/kg (cattle). The corresponding mercury concentrations were 11 g/kg, 12 g/kg and 14 g/kg (pigs) and 11 g/kg, 12 g/kg and 15 g/kg (cattle). The average concentrations were at or above the detection limit of the metal in question. According to the results obtained by the National Veterinary Institute, the cadmium concentration in pigs and cattle has decreased during the period 1973–1988. The provisional tolerable daily intake of lead/person (60 kg), recommended by GEMS/Food, is 0.43 mg. According to the results for lead levels in these products in Finland, a daily intake of 29 kg pig muscle, 33 kg cattle muscle, 11 kg pig liver, 8 kg cattle liver, 11 kg pig kidney or 4 kg cattle kidney would be required to reach this norm. The corresponding provisional tolerable daily intake of cadmium/person (60 kg) is 0.06 mg and is equivalent to 40 kg pig muscle, 46 kg cattle muscle, 2 kg pig liver, 1 kg cattle liver, 0.4 kg pig kidney and 0.2 kg cattle kidney. The validity of the methods was tested four times a year using spiked check samples.
Der Blei-, Cadmium- und Quecksilbergehalt im Muskel, Leber und Nieren von finnischen Schweinen und Rindern 1987–1988
Zusammenfassung Fleisch, Leber und Nieren von finnischen Schweinen und Rindern wurden auf Blei, Cadmium und Quecksilber untersucht. Die durchschnittlichen Bleikonzentrationen (Frischgewicht) in Schweinefleisch, -leber und -nieren betrugen 15 g/kg, 38 g/kg und 40 g/kg. Die entsprechenden Bleikonzentrationen der Rinder waren 13 g/kg, 57 g/kg und 110 g/kg. Die Untersuchung der durchschnittlichen Cadmiumkonzentrationen ergab folgende Werte: 1,5 g/kg, 28 g/kg, 170 g/kg (Schweine) und 1,3 g/kg, 61 g/kg, 350 g/kg (Rinder), und der entsprechenden Quecksilberkonzentrationen 11 g/kg, 12 /kg, 14 g/kg (Schweine) und 11 g/kg, 12 g/kg, 15 g/kg (Rinder). Die durchschnittlichen Konzentrationen des jeweils untersuchten Metalls entsprachen den Grenzwerten oder darüber. Die Cadmiumkonzentrationen der Schweine und Rinder sind nach den Untersuchungen des Staatlichen Veterinärinstitutes in Helsinki während den Jahren 1973–1988 gesunken. Der von Gems/Food empfohlene Höchstwert der tolerierten täglichen Aufnahme von Blei/Person (60 kg) beträgt 0,43 mg. Nach den Ergebnissen bezüglich der Bleikonzentration der o. a. finnischen Produkte würden die folgenden Mengen diese tägliche Norm überschreiten: 29 kg Schweinefleisch, 33 kg Rindfleisch, 11 kg Schweineleber, 8 kg Rinderleber, 11 kg Schweineniere oder 4 kg Rinderniere. Die entsprechenden Normwerte für Cadmium/Person (60 kg) ist 0,06 mg und wäre äquivalent mit 40 kg Schweinefleisch, 46 kg Rindfleisch, 2 kg Schweineleber, 1 kg Rinderleber, 0,4 kg Schweineniere und 0,2 kg Rinderniere. Die Richtigkeit der angewandten Methoden wurde viermal jährlich mit künstlich kontaminierten Proben kontrolliert.相似文献
44.
Laitinen J Julkunen-Tiitto R Rousi M Heinonen J Tahvanainen J 《Journal of chemical ecology》2005,31(10):2243-2262
This study investigates variation in the secondary chemistry of the bark of three closely related, winter-dormant species
of white birch (Betula resinifera, B. pendula, and B. platyphylla) at different ontogenetic stages by using different plant parts (top and base). The experimental birches were grown for 4 years
in two growing conditions (pot and field) at different nutrient levels. There was considerable species-specific quantitative
and qualitative variation in the secondary chemicals in bark, but this was also affected by fertilization and the age of the
plant. In general, there was greater chemical diversity in saplings than in seedlings. The study revealed three new components,
secoisolariciresinol 9-O-β-glucopyranoside and two of its derivatives, that have not been reported previously for the bark of white birches. Principal
component analysis showed that the species studied had a similar chemical composition at the juvenile stage, but as the plants
grew, they became more clearly differentiated, which indicates that the species of older plants can be identified by chemotaxonomy.
Evidently, the secondary chemistry of birches is under genetic control, but it is affected by properties of growing conditions
and ontogeny.
Electronic Supplementary Material Supplementary material to this paper is available in electronic form at 相似文献
45.
46.
Lamminen H. Sernberg V. Ruohonen K. Roine R. 《IEEE transactions on information technology in biomedicine》2001,5(2):174-177
The objective of the paper is to follow-up the success of Finnish telemedicine programs identified in 1996 in a nation-wide survey. The methods used are questionnaires sent to those in charge of a total of 40 telemedicine programs identified in 1996. Of the results of the programs responding to the survey (36 out of 40, i.e., 90%), 69% were still operative at the time of the follow-up in 1999. According to the respondents, one-third of the programs were deemed to have had an impact on the working process of the organization. The majority of the programs lacked a clear effect in this respect. In only four cases out of 36, the telemedicine program was deemed to have achieved savings, three of the programs had brought about extra costs, and four were cost neutral. However, in the majority of the cases, the respondents were not able to assess the financial impart of the program. The average duration of the programs still in progress was 4.2 years and those terminated was 2.5 years. The average number of patients treated in the programs still in progress was 370, i.e., approximately 88 patients per year. Of the telemedicine programs identified three years earlier, two-thirds were still in progress during the repeat survey. The average number of patients treated per year in these programs was relatively small, suggesting that telemedicine was not very successful in replacing traditional ways of delivering patient care. In line with this, only a minority of the programs were deemed to have had an effect on the working process of the organization, and cost savings were achieved in only a handful of cases 相似文献
47.
Marika P. Immonen Mikko Karppinen Jorma K. Kivilahti 《Microelectronics Reliability》2007,47(2-3):363-371
In this paper, the effects of environmental stresses on the properties of polymeric optical waveguides were investigated. Optical multimode waveguides were embedded on printed circuit boards by employing commercial polymers. Three optical-PCB constructions varying in board structure and in optical build-up materials were compared. The guide systems were subjected to four different tests: damp heat-high humidity, isothermal annealing, thermal shock and environmental flowing multigas test. Isothermal annealing reduced the refractive index to greatest extent. The optical-PCB structure with optical surface build-up layer was observed to be more vulnerable under temperature shock when compared with the O-PCB with optical inner layer. The buffer layer beneath the optical build-up was found to improve the stability of the optical waveguides significantly. The results indicated of a wavelength dependence to the aging factor with a failure mechanism. The factors affecting the performance and reliability of polymer-based optical waveguides on PCBs were discussed. 相似文献
48.
We have developed a novel system for content-based image retrieval in large, unannotated databases. The system is called PicSOM, and it is based on tree structured self-organizing maps (TS-SOMs). Given a set of reference images, PicSOM is able to retrieve another set of images which are similar to the given ones. Each TS-SOM is formed with a different image feature representation like color, texture, or shape. A new technique introduced in PicSOM facilitates automatic combination of responses from multiple TS-SOMs and their hierarchical levels. This mechanism adapts to the user's preferences in selecting which images resemble each other. Thus, the mechanism implements a relevance feedback technique on content-based image retrieval. The image queries are performed through the World Wide Web and the queries are iteratively refined as the system exposes more images to the user. 相似文献
49.
An Van Cleempoel Jorma Joutsensaari Esko Kauppinen Renaat Gijbels Magda Claeys 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(4):599-627
Abstract Aerosol routes were used to produce fullerene particles in the nanometer size range. Particle formation mechanisms at processing temperatures of 400-700°C were studied by measuring particle number and mass size distributions in the gas phase by a differential mobility analyzer and a low-pressure impactor respectively. Subsequently, the foils of the impactor onto which fullerene particles were collected were examined by HPLC. 相似文献
50.
Antti Rostedt Anssi Arffman Kauko Janka Jaakko Yli-Ojanperä Jorma Keskinen 《Aerosol science and technology》2014,48(10):1022-1030
The Pegasor PPS-M sensor is an electrical aerosol sensor based on diffusion charging and current measurement without particle collection. In this study, the role and effect of each component in the instrument is discussed shortly and the results from a thorough calibration measurements are presented. A comprehensive response model for the operation of the PPS-M sensor was developed based on the calibration results and computational fluid dynamics (CFD) modeling results. The obtained response model, covering the effects of the particle charger, the mobility analyzer, and both diffusion and inertial losses, was tested in the laboratory measurements with polydisperse test aerosols, where a good correlation between the model and the measured results was found.
Copyright 2014 American Association for Aerosol Research 相似文献