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1.
The hygienic working practices of the maintenance personnel as well as the hygiene of the equipment in the food industry were investigated with questionnaires and microbial surveys. The protective clothing, washing of hands and tools as well as avoiding foreign bodies left on the production lines should be targeted when the hygienic working practices are developed for maintenance personnel. Based on the questionnaire to food processors, packaging machines, conveyers, dispensers, slicing and cooling machines were considered the most problematic pieces of equipment hygienically mainly because of poor hygienic design. In order to improve food safety, both the training of maintenance personnel in food hygiene and equipment design should be more emphasised.  相似文献   
2.
In this study, Pd/Al2O3 and Pd/BaO/Al2O3 metallic monoliths were used to investigate the effect of BaO in C2H4 and CO oxidation as well as in NO reduction. A FT-IR gas analyser was used to study the activity of the catalysts. Several activity experiments carried out with dissimilar feedstreams revealed that BaO enhances CO and C2H4 oxidation as well as NO reduction reactions in rich conditions. This effect is due to BaO, which causes a decrease in the ethene poisoning of palladium. In lean conditions BaO is present in the form of Ba(OH)2 which reacts with oxidised NO releasing water. Therefore, NO was stored during the lean reaction.  相似文献   
3.
The effects of elevated atmospheric CO2 concentration on soil moisture, N2O fluxes, and biomass production of Phleum pratense were studied in the laboratory. Farmed peat and sandy soil mesocosms sown with P. pratense were fertilized with a commercial fertilizer. In peat soil 10 g N m−2 of commercial fertilizer were added and in sandy soil 15 g N m−2. In both experiments, soil moisture was regulated with deionized water; 18 mesocosms were tended to keep equally moist, and the other 18 were watered with equal amounts of water. Nine mesocosms from both watering treatments were grown under ambient (360 μmol mol−1) CO2 concentration and the remaining nine under doubled (720 μmol mol−1) CO2. N2O efflux was monitored using a closed chamber technique and a gas chromatograph. The elevated supply of CO2 increased production of above- and belowground biomass, soil moisture and N2O fluxes, but decreased the total N content in the aboveground biomass, especially for the sandy soil. In similar water levels, N2O efflux from the sandy soil was the same magnitude as that from the peat soil. In addition to moisture, N availability was the main limiting factor for N2O production, but C availability also seemed to regulate the denitrification activity. In addition to an increase in C availability the increase in the N2O efflux under the raised CO2 concentration also required a simultaneous increase in soil moisture.  相似文献   
4.
The activity of fresh and hydrothermally aged zeolite-based catalysts in the NH3-selective catalytic reduction (SCR) reaction with excess of oxygen were studied. In addition, the effect of NO2 in the gas feed as well as the acidity of the catalysts for the SCR activity was investigated. The studied catalysts were hydrogen, copper, iron and silver ion exchanged ZSM-5, mordenite, beta, ferrierite, and Y-zeolites. The investigation verifies that the zeolite-based catalysts are very promising for the ammonia SCR reaction. Especially, the activity at low and high temperatures was higher than the activity of commercial vanadia-based catalysts. From the studied catalysts, Fe-beta was the most potential one. The presence of NO2 in the inlet flow enhanced significantly the catalytic activity of fresh and hydrothermally aged zeolite catalysts. This suggests that the oxidation of NO to NO2 is probably the rate-determining step for the SCR reaction.  相似文献   
5.
Bilberry is a characteristic field layer species in the boreal forests and is an important forage plant for herbivores of the North European ecosystem. Bilberry leaves contain high levels of phenolic compounds, especially hydroxycinnamic acids, flavonols, catechins, and proanthocyanidins. We investigated the phenolic composition of bilberry leaves in two studies, one following foliar development in forest and open areas, and the other along a wide geographical gradient from south to north boreal forests in Finland. An analysis of bilberry leaves collected in open and forest areas showed that major phenolic changes appeared in the first stages of leaf development, but, most importantly, synthesis and accumulation of flavonoids was delayed in the forest compared to the high light sites. Sampling along a geographical gradient in the boreal zone indicated that leaves from higher latitudes and higher altitudes had greater soluble phenolic and flavonol levels, higher antioxidant capacity, and lower contents of chlorogenic acid derivatives. The ecological significance of the results is discussed.  相似文献   
6.
Milk casein-derived biologically active tripeptides isoleucine–proline–proline and valine–proline–proline have shown antihypertensive effects both in animal and clinical studies. Contradictory findings from clinical intervention studies may be related to different manufacturing processes. The present study aimed to compare cardiovascular effects of two different tripeptide powders in spontaneously hypertensive rat (SHR). Rats received tripeptide powders produced either by Lactobacillus helveticus fermentation (A) or Lb. helveticus plus proline specific endoprotease (B) in drinking fluid for 8 weeks. Systolic blood pressure was recorded weekly. At the end, blood and tissue samples were collected and arterial responses studied. Blood pressure was 13.6 and 14.2 mmHg lower in the groups A and B, respectively, versus the water group (P < 0.01). Vascular responses of aorta and mesenteric artery did not differ between the groups. Both tripeptide products increased urinary cGMP (P < 0.001) and decreased albumin (P < 0.05). The fermentation process did not influence the cardiovascular effects of the tripeptide powders.  相似文献   
7.
There is currently no suitable replacement for damaged temporomandibular joint (TMJ) discs after discectomy. In the present study, we fabricated bilayer biodegradable polylactide (PLA) discs comprising a non-woven mat of poly(L/D)lactide (P(L/D)LA) 96/4 and a P(L/DL)LA 70/30 membrane plate. The PLA disc was examined in combination with adipose stem cells (ASCs) for tissue engineering of the fibrocartilaginous TMJ disc in vitro. ASCs were cultured in parallel in control and chondrogenic medium for a maximum of six weeks. Relative expression of the genes, aggrecan, type I collagen and type II collagen present in the TMJ disc extracellular matrix increased in the ASC-seeded PLA discs in the chondrogenic medium. The hypertrophic marker, type X collagen, was moderately induced. Alcian blue staining showed accumulation of sulphated glycosaminoglycans. ASC differentiation in the PLA discs was close to that observed in pellet cultures. Comparison of the mRNA levels revealed that the degree of ASC differentiation was lower than that in TMJ disc-derived cells and tissue. The pellet format supported the phenotype of the TMJ disc-derived cells under chondrogenic conditions and also enhanced their hyalinization potential, which is considered part of the TMJ disc degeneration process. Accordingly, the combination of ASCs and PLA discs has potential for the development of a tissue-engineered TMJ disc replacement.  相似文献   
8.
Biodegradable polymers, mainly derivates of -hydroxy acids, are widely used today in oral- and maxillofacial surgery, orthopedics, and other fields of surgery. These biomaterials are well tolerated by living tissue and fracture fixation devices made of polylactic or polyglycolic acid are clinically widely used today. Still, there are some problems in application of biodegradable polymers. Abacterial inflammatory reactions have been noticed after the clinical introduction of these devices. Both swelling and pain at the site of implantation have also been reported. The etiology of this inflammatory reaction is still unknown, despite the numerous studies. Therefore, the aim of the present study was to further characterize this inflammatory reaction in detail, by electronmicroscopy. We prepared a mixture of -caprolactone–lactide copolymer and tricalcium phosphate and placed it in the dermis in 12 sheep. Follow-up times were 9, 14, 24, and 52 weeks. We found that the mixture caused a mild inflammatory reaction. There were no signs of cell damage. Fibroblasts, macrophages, and eosinophils were found adjacent to the copolymer. The mixture is easy to handle and can be moulded into different shapes in room temperature. The results encourage us to continue our studies to develop a filling material for bone defects.  相似文献   
9.
The broad aim of this interpretive study was to investigate the lived experiences of inter-organisational information system (IOIS) project members who worked in a 3-year-long IOIS project. The study presents an original longitudinal study of project member experiences. In this paper, we have described and analysed one core category, project power, which was derived from a grounded theory (GT) study. This study extends existing theories about power in organisational contexts, in particular the everyday use of power in projects. The paper shows how GT can be used to gain significant insights into a case study, and also generate new concepts. This paper gives detailed insights into the power issues as they played out in a complex IOIS project. This IOIS project spanned four user organisations, two suppliers, one national organisation, a research organisation and a government Ministry. One key finding is that, given the complexity of the project management structures in an IOIS project such as this, project members often resorted to formal authority as a means of getting things done, in the absence of informal links between organisations. The project history also had major ramifications on the use of power in this project.  相似文献   
10.
Development of a reliable laboratory scale test for the design of industrial catalysts is crucial. In this article, different laboratory-scale tests were compared with an industrial scale CVOCs treatment. With dichloromethane (DCM) the laboratory scale test results corresponded well to the industrial scale oxidation results. However, the perchloroethylene (PCE) conversions measured in industry were always higher than what was achieved in the laboratory scale indicating that the industrial scale catalytic incinerator operating in transient conditions is highly beneficial in PCE oxidation. It was clearly shown that in order to design high-quality laboratory scale experiments, information on complete composition and total concentration of the emission is needed but also different types of catalytic tests need to be used depending on the industrial reactor. In addition, the catalysts’ performance in an industrial VOC abatement unit was examined as the oxidation efficiencies of DCM, PCE and other hydrocarbons (OHC) were compared after 3, 10 and 23 months of operation. After 23 months and 13,065 operating hours, no significant decrease in the activity of the catalysts was observed showing that the used noble metal catalysts are highly resistant towards these demanding conditions.  相似文献   
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