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211.
One of Volvo Car Corporation's core values is "Environmental Care". Volvo Cars has a tradition of attention to the work environment and has over the years developed a working environment management system, an organisational strategy for the participation of everyone, a working environment policy, standards/specifications and methods for efficient practical performance. The Production Ergonomics Project is an example of this. In order to achieve results in ergonomics one has to work comprehensively, which means working with the product, the process, the workplace, the individuals and the work organisation. The key to success is to train all categories concerned in load ergonomics and to perform methodical ergonomic work through the whole chain from design to production. 相似文献
212.
Takafumi Shido Takumi Okazaki Maria A. Ulla Toshiyuki Fujimoto Masaru Ichikawa 《Catalysis Letters》1993,17(1-2):97-103
Rh4-xCox(CO)12 (x = 0, 2, 3) are attached by carbonyl substitution to THP (tris-hydroxymethylphospine)-grafted silica keeping their cluster frameworks. They have been characterized by Rh K-edge EXAFS (extended X-ray absorption fine structure) and Fourier transform IR spectroscopy. They exhibited high catalytic activity with > 98% selectivity in gas phase hydroformylation of ethene and propene to give aldehydes under mild conditions (40 kPa and 300–373 K).On leave from Research Center, Arakawa Chemical Industries, LTD, Tsurumi, Osaka 538, Japan.On leave from Department of Chemistry, National University of Literal, Santiago del Estero, 2829-3000, Santa Fe, Argentina. 相似文献
213.
Ulla I. Brimberg 《Journal of the American Oil Chemists' Society》1993,70(3):249-254
The mechanism of fat autoxidation is elucidated from the rate data. All the data treated here and in an earlier publication
follow the same basic rate equation, including the time function f(t) empirically derived for heterogeneous oxidation. Metals
and glass (the wall of the reaction vessel) are catalysts. Depending on the state of the catalyst, f(t)=t2 or f(t)=t. When f(t)=t, the kinetics are first-order as found for monolayer autoxidation, but in bulk phase they are complicated
by a transient stage caused by the solubilization of O2 into the hydroperoxide micelles produced in the exponential (“autocatalytic”) part of the oxidation. Certain additives, such
as inhibitors, affect the catalyst and thereby f(t). The kinetics, as determined by O2 consumption or by analysis of the remaining unreacted substrate, show the first oxidation step. It is unaffected by further
chemical changes of the primary oxidation products,e.g., decomposition of hydroperoxides and trimerization in the autoxidation of 9,11-octadecadienoic acid methyl ester. 相似文献
214.
The effect of probiotic fermented milk and inulin on the functions and microecology of the intestine 总被引:1,自引:0,他引:1
Sairanen U Piirainen L Gråsten S Tompuri T Mättö J Saarela M Korpela R 《The Journal of dairy research》2007,74(3):367-373
We investigated the effects of a probiotic fermented milk and inulin on gastrointestinal function and microecology. The study was double-blinded and comprised 66 healthy adults (22 male, 44 female), mean age 40 years (range, 22-60 years). After a 12-d baseline period the subjects were randomized to consume, for 3 weeks, 3x200 ml daily of either (1) a fermented milk with probiotics (Bifidobacterium longum BB536, Bifidobacterium spp. 420 and Lactobacillus acidophilus 145), (2) a fermented milk with the same probiotics plus 4 g inulin, or (3) a control fermented milk. During the last 7 d of the baseline and the intervention periods, the subjects kept a record of their defaecation frequency and gastrointestinal symptoms, and collected all their faeces. Intestinal transit time, stool weight and faecal enzyme activities were measured. Thirty-nine subjects were randomized to give faecal samples for analysis of pH and microbes, including lactobacilli, bifidobacteria, coliforms, Escherichia coli, Bacteroides and Clostridium perfringens. Consumption of fermented milk with probiotics or with probiotics and inulin increased the faecal number of lactobacilli (P=0.009, P=0.003) and bifidobacteria (P=0.046, P=0.038) compared with the baseline. Compared with the control fermented milk, both active products increased lactobacilli (P=0.005, ANCOVA). Subjects consuming fermented milk with probiotics and inulin suffered from gastrointestinal symptoms, especially flatulence, more than the others (P<0.001). In conclusion, the probiotic fermented milk product had a positive effect by increasing the number of lactobacilli and bifidobacteria in the colon. Inulin did not alter this effect but it increased gastrointestinal symptoms. 相似文献
215.
Maguregui M Knuutinen U Martínez-Arkarazo I Castro K Madariaga JM 《Analytical chemistry》2011,83(9):3319-3326
After many decades exposed to a polluted environment, in some areas of Marcus Lucretius House, there are clear signs that plasters and hematite pigments are suffering deterioration. In the exhaustive analysis of the black layer covering the red pigment hematite it was possible to identify magnetite (Fe(3)O(4)) as responsible for the black colour, which always appears in combination with gypsum. Thermodynamic modelling stated that the presence of gypsum as well as the transformation of hematite into magnetite is a consequence of the attack of atmospheric SO(2). 相似文献
216.
S?rensen LB Greve T Kreutzer M Pedersen U Nielsen CM Toubro S Astrup A 《Revue canadienne de la pratique et de la recherche en diététique》2011,72(4):181-185
We compared the effect on weight regain of behaviour modification consisting of either a gourmet cooking course or neurolinguistic programming (NLP) therapy. Fifty-six overweight and obese subjects participated. The first step was a 12-week weight loss program. Participants achieving at least 8% weight loss were randomized to five months of either NLP therapy or a course in gourmet cooking. Follow-up occurred after two and three years. Forty-nine participants lost at least 8% of their initial body weight and were randomized to the next step. The NLP group lost an additional 1.8 kg and the cooking group lost 0.2 kg during the five months of weight maintenance (NS). The dropout rate in the cooking group was 4%, compared with 26% in the NLP group (p=0.04). There was no difference in weight maintenance after two and three years of follow-up. In conclusion, weight loss in overweight and obese participants was maintained equally efficiently with a healthy cooking course or NLP therapy, but the dropout rate was lower during the active cooking treatment. 相似文献
217.
Riina Ritasalo Ulla Kanerva Yanling Ge Simo-Pekka Hannula 《Metallurgical and Materials Transactions B》2014,45(2):489-496
In this work, dispersion strengthening of copper by diamonds is explored. In particular, the influence of 50- and 250-nm diamonds at contents of 3 and 6 vol. pct on the mechanical and thermal properties of pulsed electric current sintered (PECS) Cu composites is studied. The composite powders were prepared by mechanical alloying in argon atmosphere using a high-energy vibratory ball mill. The PECS compacts prepared had high density (>97 pct of T.D.) with quite evenly distributed diamonds. The effectiveness of dispersoids in increasing the microhardness was more pronounced at a smaller particle size and larger volume fraction, explained by Hall–Petch and Orowan strengthening models. The microhardness of Cu with 6 and 3 vol. pct nanodiamonds and pure sm-Cu (submicron-sized Cu) was 1.77, 1.46, and 1.02 GPa, respectively. In annealing experiments at 623 K to 873 K (350 °C to 600 °C), the composites with 6 vol. pct dispersoids retained their hardness better than those with less dispersoids or sm-Cu. The coefficient of thermal expansion was lowered when diamonds were added, being the lowest at about 14 × 10?6 K?1 between 473 K and 573 K (200 °C and 300 °C). Good bonding between the copper and diamond was qualitatively demonstrated by nanoindentation. In conclusion, high-quality Cu-diamond composites can be produced by PECS with improved strength and better thermal stability than for sm-Cu. 相似文献
218.
219.
This comprehensive study focused on the spatial and seasonal variations of organophosphorus flame retardants and plasticizers (OPs) in surface water from the estuary of the River Elbe and the German Bight (North Sea). 100 surface water samples were extracted by solid phase extraction (SPE) and analyzed by gas chromatography-mass spectrometry (GC-MS) with regard to 16 different OPs. The dominating substance was found to be tris(1-chloro-2-propyl) phosphate (TCPP) (Elbe: 40-250 ng L−1, German Bight: 3-28 ng L−1). Furthermore, triethyl phosphate (TEP), tri-iso-butyl phosphate (TiBP), tris(2-butoxyethyl) phosphate (TBEP), and triphenylphosphine oxide (TPPO) were detected in concentrations up to 180 ng L−1. Seasonal trends were detected for the longitudinal profile of the Elbe estuary. Besides the dilution of river water with North Sea water toward the mouth, leading to decreasing concentrations at the four sampling cruises (March, May, August, and October, 2010), an additional depletion of non-halogenated OPs was observed in summer which is supposed to be due to biodegradation or photodegradation.In addition, a comparison of all important tributaries of the German Bight (Elbe, Ems, and Weser) as well as the indirect tributaries Meuse, Rhine, and Scheldt was done by multivariate statistical methods. It could be shown that the contribution of non-halogenated alkylated OPs in the Rhine was higher than in all other tributaries. The riverine input of OPs into the North Sea via the investigated tributaries was estimated to be about 50 t yr−1. 相似文献
220.
Åse Mattsson Maria Malmlöf Albrecht Seidel Ulla Stenius Bengt Jernström 《Polycyclic Aromatic Compounds》2013,33(4-5):392-401
The human lung cancer cell line A549 was exposed to diol epoxides (DEs) and the effect on DNA damage signaling proteins was studied. The DEs used were derived from the bay-region PAHs chrysene; CDE and dibenz[a,h]anthracene; DBADE, or the fjord-region PAHs benzo[c]chrysene; B[c]CDE, benzo[g]chrysene; B[g]CDE and benzo[c]phenanthrene; B[c]PhDE. All DEs induced a rapid response on Mdm2, p53 and histone H2AX phosphorylation, where Mdm2 was the most sensitive marker of DNA damage. Fjord-region DEs induced a stronger and more persistent effect on the proteins studied than the bay-region DEs. This variance is likely to reflect differences in adduct recognition and handling by nucleotide excision repair. The stimulating effect of DEs on histone H2AX phosphorylation demonstrated that, in addition to DNA strand breaks and UV-induced photoproducts, stable and bulky DNA-adducts also possess this capacity. 相似文献