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981.
982.
This study examines supervisor and subordinate perceptions of and attributions for psychological contract breach. The data suggest that supervisor and subordinate perceptions are most likely to differ on the extent to which the organization violated its obligations to provide fair pay, advancement opportunities, and a good employment relationship. In addition, the results indicate that the greater the degree of psychological contract breach reported by subordinates, the less committed they are to the organization and the lower their job performance (as rated by their supervisor). Moreover, when psychological contract breach is perceived, supervisors' and subordinates' attributions regarding the reasons for the breach are likely to differ. Specifically, the findings suggest that subordinates are more likely to attribute breach to the organization's intentional disregard for the commitments that it had made to the employee, while supervisors are more inclined to attribute breach to situations beyond the organization's direct control. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
983.
利用造纸黑液制备水煤浆添加剂 总被引:5,自引:0,他引:5
利用造纸黑液中有效成分,经过适当处理制备水煤浆添加剂,并且对添加剂的性能进行了测试。结果表明,依照该工艺生产的添加剂,性能优良,能够满足工业生产需要。 相似文献
984.
N. K. Woodfield J. W. S. Longhurst C. I. Beattie D. P. H. Laxen 《Water, Air, & Soil Pollution: Focus》2002,2(5-6):677-688
Across the United Kingdom, the majority of local authoritieshave now completed their first phase of local air qualityreview and assessment work, as required under the AirQuality Strategy for England, Scotland, Wales and NorthernIreland (DETR, 2000a). Emerging from this first phasework is an anticipated suite of over 110 Air QualityManagement Areas (AQMAs). These areas are identifiedlocations where one or more of the national air qualityobjectives are predicted to exceed by specific target dates,and their spatial extent and shape is emerging as highlyvariable. Local authorities are guided to use a variety ofscientific tools to underpin the scientific assessments, anda consideration of uncertainty in both the tools used andsubsequent delineation of AQMAs is likely to affect theemerging management areas significantly. With subsidiarity underpinning the process of local air qualitymanagement (LAQM), local decision-making is anticipated toinfluence the outcome of the LAQM process in its entirety,with the declaration of AQMAs necessitating the preparationand implementation of air quality action plans. UKexperience of the effective management of local air quality,through the designation of AQMAs, demonstrates a valuableframework for other European countries developing mechanismsto manage air quality locally. 相似文献
985.
P. Herzsprung K. Friese R. Frömmichen J. Göttlicher M. Koschorreck W. V. Tümpling Jr. K. Wendt-Potthoff 《Water, Air, & Soil Pollution: Focus》2002,2(3):123-140
In the past five years, enclosures have beeninstalled in an acidic mining lake in Lusatia to investigate insitu remediation processes. They were treated with straw, withstraw and Carbokalk, or with Carbokalk alone, where Carbokalkis a by-product of the sugar industry (solid precipitate ofnon-sugars after lime clarification of extracted sugar beetjuice). Sediment samples were taken as cores to get informationabout the behaviour of organic and inorganic components insediment pore-water with depth. Vertical distributions of pH,soluble reactive phosphate, nitrate, ammonium, silica,aluminium, iron, manganese, calcium, magnesium, sodium,potassium, sulphate, and DOC were measured. The resultingprofiles, each consisting of 15 data points at differentdepths, were compared by cluster analysis. The similarities ofsediment cores from different treated enclosures relating toprofiles of chemical components were discussed. Increasedconcentrations of potassium and sulphate were found in pore-water after substrate treatment. The data imply dissolution ofpotassium iron sulphate hydroxide minerals (jarosite) after anincrease of pH caused by dissolution of lime and by sulphatereducing processes which were stimulated by organic substrateaddition. 相似文献
986.
Biological Pollutants: Alien Fishes in Mountain Lakes 总被引:2,自引:0,他引:2
Many lakes in the national parks of the Canadian Rockies were stocked with alien fish species in the early to mid 20th century. Changes to Parks Canada's mandate require the original communities of these lakes to be restored. We document the changes to invertebrate communities caused by the stocking of alien fishes into three fishless alpine lakes, and describe the results of two restoration experiments, one the reintroduction of Hesperodiaptomus arcticus, a planktonic predator that had been eliminated from Snowflake Lake by stocked fish, and the other the removal of brook trout (Salvelinus fontinalis) from Bighorn Lake. In both cases, there were great changes to the zooplankton communities, which required several years to complete, probably because of the cold water and unproductive nature of the lakes. Many of the invertebrate species extirpated by stocked alien fishes co-exist with native fish species in nearby lakes. Possible reasons are discussed. 相似文献
987.
Development of Stream Water Chemistry during Spring Melt in a Northern Hardwood Forest 总被引:1,自引:0,他引:1
Semkin R. G. Hazlett P. W. Beall F. D. Jeffries D. S. 《Water, Air, & Soil Pollution: Focus》2002,2(1):37-61
The role of snowmelt and subsurface hydrology in determiningthe chemistry of a small headwater stream in the TurkeyLakes Watershed (TLW) was evaluated for the spring meltperiods 1992 to 1996. Spring runoff is the dominanthydrological event at the TLW each year. Processesoccurring within the snowpack during snowmelt wereprincipally responsible for the above-ground changes inchemical fluxes relative to bulk deposition (the effect ofwinter throughfall was minimal). Large changes in chemicalfluxes occurred below ground. Organic matter decomposition,weathering, nitrification, and element cycling are some ofthe more important below-ground processes that operateduring the snow accumulation and ablation season and controlthe composition of the water ultimately appearing in thestream. Maximum stream discharge was accompanied byelevated concentrations of H+, NO3
-, K+,NH4
+, DOC, Al and Mn, but reduced levels ofCa2+, Mg2+, SO4
2- and SiO2. Theconcentration-discharge relationships were consistent withwater movement through and above the forest floor duringpeak discharge, a flowpath facilitated by rapid infiltrationof meltwater and the existence of a relatively impermeablelayer in the mineral soil creating a perched water table. Averaged over the five periods of snow accumulation andablation, it was estimated that pre-melt stream flow, andwater routed through the forest floor and through the uppermineral soil contributed 9, 28 and 63%, respectively, ofthe discharge measured at the outlet of the catchment. Theforest floor contribution would be greater at peak dischargeand at higher elevations. An end-member mixing modelestimated concentrations of SO4
2-, NO3
-,Cl-, Ca2+, Mg2+, Na+ and Al that werecomparable to average values measured in the stream. Othervariables (NH4
+, H+, K+ and DOC) wereover-estimated implying retention mechanisms operatingoutside the model assumptions. 相似文献
988.
日常工作中,由于机械伤害常常给人造成痛苦,甚至终身残疾。怎样才能有效地防止机械伤害事故呢?首先要正确分析产生机械伤害事故的原因,然后采取相应的安全防范措施。形成机械伤害事故的原因: 1.修理、检查机械时,忽视安全措施。在线检修时,未采取必要的预防措施;断电作业,电源处未悬挂警示牌。 2.安全防护装置不健全或形同虚设。 3.电源布局混乱,不利于紧急停车。 4.违章作业,随便进入危险作业区。 5.不熟悉操作规程,遇有紧急情况发生判断错误。 相似文献
989.