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991.
Research on work aggression or anger has typically focused on supervisors and co‐workers as the instigators of aggression; however, aggressive customers are also likely and may have unique consequences for the employee. We explore this phenomenon with a sample of 198 call center employees at two work sites. The employees reported that customer verbal aggression occurred 10 times a day, on average, though this varied by race and negative affectivity. Using LISREL, our data indicated that both the frequency and stress appraisal of customer aggression positively related to emotional exhaustion, and this burnout dimension mediated the relationship of stress appraisal with absences. Stress appraisal also influenced employees' emotion regulation strategies with their most recent hostile caller. Employees who felt more threatened by customer aggression used surface acting or vented emotions, while those who were less threatened used deep acting. Job autonomy helped explain who found these events more stressful, and implications of these results are discussed. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
992.
Tao Liang Hao Wang Hsiang‐te Rung Chao‐sheng Zhang 《Journal of the American Water Resources Association》2004,40(6):1499-1510
ABSTRACT: Five types of land use/land covers in the West Tiaoxi watershed of China were studied for nutrient losses in artificial rainstorm runoff. A self‐designed rainfall simulator was used. In situ rainfall simulations were used to: (1) compare the concentrations of nitrogen and phosphorous in different land use/land covers and (2) evaluate the flux of nitrogen and phosphorous export from runoff and sediment in various types of land use/land covers. Three duplicated experiments were carried out under rain intensity of 2 mm/min, each lasting 32 minutes on a 3 m2 plot. Characteristics of various species of nitrogen and phosphorous in runoff and sediment were investigated. The results showed that the concentrations of total nitrogen (TN) and total phosphorous (TP) were greatest in runoff from mulberry trees and smallest from pine forest. The TN and TP export was mainly from suspended particulate in runoff. TN and TP exports from the top 10 cm layer of five types of land use/land covers were estimated as high as 4.66 to 9.40 g/m2 and 2.57 to 4.89 g/m2, respectively, of which exports through sediment of runoff accounted for more than 90 percent and 97 percent. The rate of TN and TP exports ranged from 2.68 to approximately 14.48 and 0.45 to approximately 4.11 mg/m2/min in runoff; these rates were much lower than those of 100.01 to approximately 172.67 and 72.82 to approximately 135.96 mg/m2/min in the runoff sediment. 相似文献
993.
Pote DH Kingery WL Aiken GE Han FX Moore PA Buddington K 《Journal of environmental quality》2003,32(6):2392-2398
Poultry litter provides a rich source of nutrients for perennial forages, but the usual practice of surface-applying litter to pastures can degrade water quality by allowing nutrients to be transported from fields in surface runoff, while much of the NH4-N volatilizes. Incorporating litter into the soil can minimize such problems in tilled systems, but has not been used for perennial forage systems. In this study, we minimized disturbance of the crop, thatch, and soil structure by using a knifing technique to move litter into the root zone. Our objective was to determine effects of poultry litter incorporation on quantity and quality of runoff water. Field plots were constructed on a silt loam soil with well-established bermudagrass [Cynodon dactylon (L.) Pers.] and mixed grass forage. Each plot had 8 to 10% slopes, borders to isolate runoff, and a downslope trough with sampling pit. Poultry litter was applied (5.6 Mg ha(-1)) by one of three methods: surface-applied, incorporated, or surface-applied on soil-aeration cuts. There were six treatment replications and three controls (no litter). Nutrient concentrations and mass losses in runoff from incorporated litter were significantly lower (generally 80-95% less) than in runoff from surface-applied litter. By the second year of treatment, litter-incorporated soils had greater rain infiltration rates, water-holding capacities, and sediment retention than soils receiving surface-applied litter. Litter incorporation also showed a strong tendency to increase forage yield. 相似文献
994.
Sorption data and subsequent predictive models for evaluating acidic pesticide behavior on variable-charge soils are needed to improve pesticide management and environmental stewardship. Previous work demonstrated that sorption of pentachlorophenol (PCP), a model organic acid, was adequately modeled by accounting for pH-and pKa-dependent chemical speciation and using two organic carbon-normalized sorption coefficients; one each for the neutral and anionic species. Such models do not account for organic anion interaction to positively charged surface sites, which can be significant for variable-charge minerals present in weathered soils typical of tropical and subtropical regions. The role of anion exchange in sorption of ionizable chemicals by variable-charge soils was assessed by measuring sorption of PCP by several variable-charge soils from aqueous solutions of CaCl2, CaSO4, Ca(H2PO4)2 as a function of pH. Differences in sorption from phosphate and chloride electrolyte solutions were attributed to pentachlorophenolate interactions with anion exchange sites. Suppression of PCP sorption by phosphate ranged from negligible in a soil with essentially no positively charge sites, as measured by negligible anion exchange capacity, to as much as 69% for variable-charge soils. Pentachlorophenolate exchange correlated well with the ratio of pH-dependent anion exchange capacity to net surface charge. Sorption reversibility of PCP by both CaCl2 and Ca(H2PO4)2 solutions was also demonstrated. Results for PCP clearly demonstrate that sorption to anion exchange sites in variable-charge soils should be considered in assessing pesticide mobility and that phosphate fertilizer application may increase the mobility of acidic pesticides. 相似文献
995.
996.
把超速旋转工艺引入高压容器自紧过程,提出旋转自紧方法,并对平面应变问题导出了厚壁圆管在旋转时的弹塑性及塑性极限的应力解和停转后的残余应力解,所得结果表明,由于残余应力的存在而导致了圆管弹性强度极限的提高,达到了自紧的效果。 相似文献
997.
应用浮游植物对扎龙自然保护区水质的初步评价 总被引:3,自引:0,他引:3
通过对扎龙自然保护区水体中浮游植物调查及运用几种评价公式分析,评价结论为:扎龙水体浮游植物由8门60个属组成,数量在19 515×10~2~23 755×10~3个/升之间;水质属中污染型,同一年度污染情况为:8月>6月,北区>南区。 相似文献
998.
Han JS Moon KJ Kong BJ Lee SJ Kim JE Kim YJ 《Environmental monitoring and assessment》2005,107(1-3):221-237
PM2.5 aerosol samples were collected at Gosan in Jeju Island during six intensive measurement periods between November 2001 and
August 2003. In order to investigate the chemical composition of fine particles, major ion components, trace elements, and
elemental and organic carbon were analyzed. Quite different seasonal characteristic in the chemical composition of fine particles
was observed. The concentration of most secondary aerosol components showed a summer minimum and a winter maximum with higher
correlation between them at Gosan. This fact clearly reveals the possibility of long-range transport of such pollutants in
winter. On the other hand, OC and EC had the highest concentration and good correlation with ion components, such as K+, Ca2+ in fall. It means that biomass burning could significantly influence the ambient fine carbonaceous particulate in fall, which
was primarily long-range transported. 相似文献
999.
1000.
对吹气-吸收法测定废水中硫化物进行了吸收试验,提出了用去离子除氧水配制硫化物标液,可增加其稳定性;用ISO硫化物吹脱器取代普通气吸收装置,可提高硫化物回收率。试验结果表明,改进后方法的精密度,准确度及适用怀强垃令人满意。 相似文献