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11.
Deutsch's theory of cooperation and competition or goal linkage has been developed by considerable experimental research, but is little used to study interdependence in organizations. Organizational members were interviewed in depth on a specific interaction and completed a questionnaire to describe their relationships with their co-workers and supervisors. Positive linkage, in contrast to negative linkage, was related to effective negotiations and the development of feelings of success and satisfaction. Positive linkage compared to negative linkage was also found to stengthen work relationshps and facilitate productivity. Independent linkage had dynamics similar to negative linkage, but was positively related to productivity. Questionnaire results also support the theory of goal linkage. Goal linkage, dynamics, and outcomes appear to be self-sealing and mutually causal. Results suggest that goal linkage theory has considerable potential to describe and influence actual organizational work relationships.  相似文献   
12.
Two studies were designed to test hypotheses derived from Locke's (1969, 1976, 1984) model of job satisfaction. Consistent with the model, both studies found that perceived have-want discrepancy scores were powerful predictors of facet job satisfaction. In addition, facet importance tended to moderate this relationship in the manner predicted by Locke. Workers who viewed a job facet as having high importance were more satisfied with a small perceived have-want discrepancy and more dissatisfied with a large discrepancy than workers who viewed the facet as having low importance. Finally, as expected, facet importance failed to moderate the relationship between facet satisfaction and overall job satisfaction. This finding supports Locke's proposition that facet satisfaction scores are ‘implicitly weighted’ by facet importance. Implications and directions for future research are discussed.  相似文献   
13.
Characteristics of bricks made from waste steel slag   总被引:4,自引:0,他引:4  
The characteristics of bricks made from steel slag were investigated in this research. Slag addition was shown to reduce the required firing temperature. When the firing temperature was greater than 1050 degrees C and the slag addition less than 10%, the bricks met ROC national standard CNS 3319 third-class brick for builders. The percentage of slag increased as the quartz and kaolin decreased in the sintered samples while the magnesium aluminum silicate and calcium silicate increased. There were no new crystal phases observed in these samples.  相似文献   
14.
Lead poisoning of waterfowl from direct ingestion of wetland mine tailings has been reported at the Coeur d'Alene River basin in Idaho. A greenhouse study was conducted to evaluate the effects of surface applications of amendments on lead bioavailability in the tailings. Treatments included sediment only, and sediment with three different surface amendments: (i) biosolids compost plus wood ash, (ii) compost + wood ash + a low SO4(2-) addition as K2SO4, and (iii) compost + wood ash + a high SO4(2-) addition. Measured variables included growth and tissue Pb, Zn, and Cd concentration of arrowhead (Sagittaria latifolia Willd.) and cattail (Typha latifolia L.) and soil pH, redox potential (Eh), pore water Pb, Pb speciation by X-ray absorption spectroscopy, and in vitro Pb bioavailability. The compost + ash amendment alleviated phytotoxicity for both plant species. Bioavailability of Pb as measured by a rapid in vitro extract decreased by 24 to 34% (over control) in the tailings directly below the amendment layer in the compost + SO4 treatments. The ratio of acid volatile sulfide (AVS) to simultaneously extracted metals (SEM) also indicated a reduction in Pb bioavailability (1:40 control, 1:20 compost, 1:8 compost + low SO4, and 1:3 compost + high SO4). Extended X-ray adsorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) spectroscopy data indicated that lead sulfide was greater after 99 d in the treatments that included additions of sulfate. These results indicated that, under reducing conditions, surface amendments of compost + wood ash (with or without sulfate) decreased the bioavailability of Pb in metal-contaminated mine tailings.  相似文献   
15.
ABSTRACT: Iron, added as (Fe-EDTA)-, was found stimulatory to V. spiralis at a concentration of 0.05 ppm. (Fe-EDTA)- had no effect upon growth of V. neotropicalis as measured by changes in dissolved oxygen and dry weight. Results are compared with those derived from similar studies with Hydrilla verticillata and Egeria densa. The implications of lake drawdown and aeration are discussed.  相似文献   
16.
ABSTRACT: The choice of a lake rehabilitation technique can be assisted by laboratory experiments concerned with the composition and properties of the sediments. This work on Sawgrass Lake, Pinellas County, Florida, provides an example of the type of laboratory information that can be useful towards making decisions regarding the most effective restorative techniques. Experiments include chemical analysis of sediment (water content, organic content, pesticides, nutrients), rate of sediment compaction and rehydration at ambient conditions, and the effect of treatment with alum and other chemicals.  相似文献   
17.
Particulate matter, including coarse particles (PM2.5–10, aerodynamic diameter of particle between 2.5 and 10 μm) and fine particles (PM2.5, aerodynamic diameter of particle lower than 2.5 μm) and their compositions, including elemental carbon, organic carbon, and 11 water-soluble ionic species, and elements, were measured in a tunnel study. A comparison of the six-hour average of light-duty vehicle (LDV) flow of the two sampling periods showed that the peak hours over the weekend were higher than those on weekdays. However, the flow of heavy-duty vehicles (HDVs) on the weekdays was significant higher than that during the weekend in this study. EC and OC content were 49% for PM2.5–10 and 47% for PM2.5 in the tunnel center. EC content was higher than OC content in PM2.5–10, but EC was about 2.3 times OC for PM2.5. Sulfate, nitrate, ammonium were the main species for PM2.5–10 and PM2.5. The element contents of Na, Al, Ca, Fe and K were over 0.8 μg m?3 in PM2.5–10 and PM2.5. In addition, the concentrations of S, Ba, Pb, and Zn were higher than 0.1 μg m?3 for PM2.5–10 and PM2.5. The emission factors of PM2.5–10 and PM2.5 were 18 ± 6.5 and 39 ± 11 mg km?1-vehicle, respectively. The emission factors of EC/OC were 3.6/2.7 mg km?1-vehicle for PM2.5–10 and 15/4.7 mg km?1-vehicle for PM2.5 Furthermore, the emission factors of water-soluble ions were 0.028(Mg2+)–0.81(SO42?) and 0.027(NO2?)–0.97(SO42?) mg km?1-vehicle for PM2.5–10 and PM2.5, respectively. Elemental emission factors were 0.003(V)–1.6(Fe) and 0.001(Cd)–1.05(Na) mg km?1-vehicle for PM2.5–10 and PM2.5, respectively.  相似文献   
18.
Although still widely assumed to be disruptive, conflict, when managed appropriately, has been found to make teamwork within and between organizations effective. However, organizational members often have competitive relationships and orientations to dealing with conflict that lead to conflict avoidance and escalation, approaches that sabotage decision‐making and relational bonds. Conflict researchers have contributed to the bad reputation of conflict by confounding conflict and competition and suggesting that the kind of conflict, rather than its management, determines its outcomes. Studies in the West and East indicate that by developing cooperative relationships and the skills to discuss diverse views open‐mindedly, organizations can empower managers and employees to use conflict to probe problems, create innovative solutions, learn from their experience, and enliven their relationships. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
19.
We conducted a comprehensive evidence-based review on the epidemiology and current standard of care of gastroschisis management as well as the pathophysiology, rationale and feasibility of fetal therapy as a viable alternative. Gastroschisis is a periumbilical abdominal wall defect characterized by abdominal viscera herniation in utero. It affects 4 in 10 000 live births, but the prevalence has steadily increased in recent years. Gastroschisis is typically diagnosed on routine second-trimester ultrasound. The overall prognosis is favorable, but complex gastroschisis, which accounts for about 10% to 15% of cases, is associated with a higher mortality, significant disease burden and higher healthcare costs due to long- and short-term complications. The current standard of care has yet to be established but generally involves continued fetal surveillance and multidisciplinary perinatal care. Postnatal surgical repair is achieved with primary closure, staged silo closure or sutureless repair. Experimental animal studies have demonstrated the feasibility of in utero closure, antiinflammatory therapy and prenatal regenerative therapy. However, reports of early preterm delivery and amnioinfusion trials have failed to show any benefit in humans. Further experimental studies and human trials are necessary to demonstrate the potential benefit of fetal therapy in gastroschisis.  相似文献   
20.
Extensive aerosol optical properties, particle size distributions, and Aerodyne quadrupole aerosol mass spectrometer measurements collected during TRAMP/TexAQS 2006 were examined in light of collocated meteorological and chemical measurements. Much of the evident variability in the observed aerosol-related air quality is due to changing synoptic meteorological situations that direct emissions from various sources to the TRAMP site near the center of the Houston-Galveston-Brazoria (HGB) metropolitan area. In this study, five distinct long-term periods have been identified. During each of these periods, observed aerosol properties have implications that are of interest to environmental quality management agencies. During three of the periods, long range transport (LRT), both intra-continental and intercontinental, appears to have played an important role in producing the observed aerosol. During late August 2006, southerly winds brought super-micron Saharan dust and sea salt to the HGB area, adding mass to fine particulate matter (PM2.5) measurements, but apparently not affecting secondary particle growth or gas-phase air pollution. A second type of LRT was associated with northerly winds in early September 2006 and with increased ozone and sub-micron particulate matter in the HGB area. Later in the study, LRT of emissions from wildfires appeared to increase the abundance of absorbing aerosols (and carbon monoxide and other chemical tracers) in the HGB area. However, the greatest impacts on Houston PM2.5 air quality are caused by periods with low-wind-speed sea breeze circulation or winds that directly transport pollutants from major industrial areas, i.e., the Houston Ship Channel, into the city center.  相似文献   
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