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751.
In 1992 a comprehensive health-promotion project was initiated in seven nursing-homes in the Netherlands. This project was designed to implement an ergonomic-educational programme, with the intention of reducing physical workload and to bring about safe working in order to prevent work-related musculoskeletal complaints. After a period of external support, employees of the nursing-homes should be able to proceed with the programme independently. In this paper the content of the programme and its underlying strategies and theories are described. So far, the programme has got off to a good start in all the nursing-homes. Positive effects of the programme could be demonstrated and guidelines and protocols for safe working were introduced. However, it is as yet too early for definitive conclusions to be drawn regarding the aspect of continuity. 相似文献
752.
The use of pressure-volume-temperature (PVT) studies in processing of a biodegradable plastic composition made from soy protein
isolate and corn starch is described. The ability of PVT measurements to predict the combined effects of pressure, volume,
and temperature effects is demonstrated. The results show that the PVT relations of the plastic can be predicted by using
a regression analysis similar to the Tait equations of state. A change in slope of the PVT curves was observed at around 80‡C,
which is ascribed to the glass-transition process of the plastic. Evidence of onset of thermal degradation of the plastic
was observed at ca. 160‡C under 0 to 200 MPa isobaric pressure. This thermal degradation precluded determination of the crystal
melting point of the plastic. 相似文献
753.
754.
755.
This study examined the relationships between culture, individual attributes, and self‐rating behavior among 1,786 university students in Canada, Hong Kong, Taiwan, mainland China, and Japan, and in doing so extended and refined the cultural relativity hypothesis. It explored the difference between vertical and horizontal individualists in self‐rating behavior, and examined the mediating effects of two individual attributes, self‐enhancement propensity and general self‐efficacy in the relationship between individualism and self‐rating behavior. The results confirmed that individualism is the cultural driver for self‐rating leniency, and that the individual‐level assessment of individualism is a stronger predictor of self‐rating leniency than are culture‐level differences. Vertical individualism was found to be positively related to self‐enhancement propensity, which in turn was positively related to self‐rating. Whereas, horizontal individualism was positively related to general self‐efficacy, which in turn had a positive relationship with self‐rating. We discuss the implications of the results for academic research and practical management. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
756.
Elvis G. Ngwenya Maud Walsh Caroline A. Metosh‐Dickey Ralph J. Portier 《补救:环境净化治理成本、技术与工艺杂志》2006,16(2):79-90
Biological and physicochemical approaches were utilized in a treatment train for acid mine dis charge (AMD) waters. Anaerobic bioreactors, chemical precipitation reactors, and biopolymer chelation reactors, operated in static, semicontinuous, and continuous flow modes, removed significant quantities of metals and sulfates associated with AMD water. Static tests indicated accept able copper removal via precipitation by generation of hydrogen sulfide in anaerobic reactors. However, low pH affected the biopolymer coating in the chelation reactor, resulting in loss of bed surface. Corrections of AMD to pH > 7 resulted in some metal precipitationprior to biopolymer treatment. A series of static semicontinuous tests at pH 5.0 provided improved metal and sulfate removal. Copper (Cu+) was reduced to trace concentrations, while manganese (Mn+), although reduced, proved to be the most recalcitrant of the metals. © 2006 Wiley Periodicals, Inc. 相似文献
757.
758.
Calculating overpressure from BLEVE explosions 总被引:3,自引:0,他引:3
E. Planas-Cuchi J. M. Salla J. Casal 《Journal of Loss Prevention in the Process Industries》2004,17(6):431-436
Although a certain number of authors have analyzed the prediction of boiling liquid expanding vapour explosion (BLEVE) and fireball effects, only very few of them have proposed methodologies for predicting the overpressure from such explosions. In this paper, the methods previously published are discussed and shown to introduce a significant overestimation due to the erroneous thermodynamic assumptions—ideal gas behaviour and isentropic vapour expansion—on which they are based (in fact, they give the maximum value of overpressure which can be caused by a BLEVE). A new approach is proposed, based on the—more realistic—assumption of an adiabatic and irreversible expansion process; the real properties of the substance involved in the explosion are used. The two methods are compared through the application to a given case. 相似文献
759.
T. D. Blackall M. R. Theobald C. Milford K. J. Hargreaves E. Nemitz L. J. Wilson J. Bull P. J. Bacon K. C. Hamer S. Wanless M. A. Sutton 《Water, Air, & Soil Pollution: Focus》2004,4(6):279-285
Ammonia emissions from two contrasting seabird colonies in Scotland were measured, based on the determination of atmospheric concentrations downwind of the colonies. Atmospheric concentrations of ammonia (NH3) across the downwind plume were compared with the inverse application of a Gaussian dispersion model (ID) to calculate the modelled NH3 emission that would generate the measured cross-wind-integrated plume concentration. In parallel, a tracer gas (sulphur hexafluoride, SF6) was released from the colonies with air samples taken to allow determination of SF6 concentrations. On the basis of the known emission rate of SF6, the magnitude of ammonia emissions was estimated by the cross-wind-integrated tracer ratio (TR) of NH3/SF6 concentrations. Coupled with data on annual bird attendance, the measurements indicate annual emissions from the Isle of May and the Bass Rock of 18 and 132 tonnes NH3-N year–1, respectively. The measured NH3 emissions were compared with estimates of seabird nitrogen excretion to estimate the proportion of excreted N that is volatilised as NH3 (FNr). The emission estimates of the two methods compared favourably, giving 4 and 6 kg NH3-N h–1 (FNr = 15%) for the Isle of May for the ID and TR methods, respectively, and 21 and 25 kg NH3-N h–1 (FNr = 50%) for the Bass Rock for the ID and TR methods, respectively. The results provide the first measurement-based estimates to allow regional up scaling of ammonia emissions from seabirds. 相似文献
760.
David Fowler Jennifer B. A. Muller Lucy J. Sheppard 《Water, Air, & Soil Pollution: Focus》2004,4(6):3-8
This paper provides the background to this special issue, outlining the extent to which the global atmospheric nitrogen cycle has been modified by human activity and outlining the range of effects. The global total emissions of reduced and oxidized nitrogen, amount to 124 Tg N, and exceed those from natural sources (34 Tg N) by almost a factor of four showing the extent to which anthropogenic activity has taken over the global N cycle. Of the 124 Tg N, 70 Tg N is emitted in the oxidized form, largely as NO and 70% of which results directly from anthropogenic activity. The remaining 54 Tg N is emitted as NH3, (66% anthropogenic). The enhanced nitrogen emissions are associated with a range of local, regional and global issues including, acidification, eutrophication, climate change, human health and tropospheric O3. The paper also places the Global Nitrogen Enrichment (GaNE) research programme in the UK in a wider perspective. 相似文献