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431.
Despite the importance of employee learning for organizational effectiveness, scholars have yet to identify the factors that influence employees' perception of individual learning. This paper identified employees' self‐efficacy as a potential antecedent to their perception of individual learning in the context of teamwork. We also hypothesized that team‐learning behavior had a moderating effect on the relationship between employees' self‐efficacy and their perception of individual learning. We conducted a study of 236 teams working in a retail firm, comprising 236 team supervisors and 1397 employees, and analyzed the data using hierarchical linear modeling. This study revealed that employees' individual‐level self‐efficacy was positively associated with their perception of individual learning in teams. Additionally, team‐learning behaviors moderated the positive relationship between employees' self‐efficacy and the perception of individual learning. This study has theoretical and practical implications for a more nuanced understanding of the perception of individual learning in the context of teamwork. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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433.
Removal of ammonia solutions used in catalytic wet oxidation processes   总被引:9,自引:0,他引:9  
Hung CM  Lou JC  Lin CH 《Chemosphere》2003,52(6):989-995
Ammonia (NH(3)) is an important product used in the chemical industry, and is common place in industrial wastewater. Industrial wastewater containing ammonia is generally either toxic or has concentrations or temperatures such that direct biological treatment is unfeasible. This investigation used aqueous solutions containing more of ammonia for catalytic liquid-phase oxidation in a trickle-bed reactor (TBR) based on Cu/La/Ce composite catalysts, prepared by co-precipitation of Cu(NO(3))(2), La(NO(3))(2), and Ce(NO(3))(3) at 7:2:1 molar concentrations. The experimental results indicated that the ammonia conversion of the wet oxidation in the presence of the Cu/La/Ce composite catalysts was determined by the Cu/La/Ce catalyst. Minimal ammonia was removed from the solution by the wet oxidation in the absence of any catalyst, while approximately 91% ammonia removal was achieved by wet oxidation over the Cu/La/Ce catalyst at 230 degrees C with oxygen partial pressure of 2.0 MPa. Furthermore, the effluent streams were conducted at a liquid hourly space velocity of under 9 h(-1) in the wet catalytic processes, and a reaction pathway was found linking the oxidizing ammonia to nitric oxide, nitrogen and water. The solution contained by-products, including nitrates and nitrites. Nitrite selectivity was minimized and ammonia removal maximized when the feed ammonia solution had a pH of around 12.0.  相似文献   
434.
Measurements collected using five real-time continuous airborne particle monitors were compared to measurements made using reference filter-based samplers at Bakersfield, CA, between December 2, 1998, and January 31, 1999. The purpose of this analysis was to evaluate the suitability of each instrument for use in a real-time continuous monitoring network designed to measure the mass of airborne particles with an aerodynamic diam less than 2.5 microns (PM2.5) under wintertime conditions in the southern San Joaquin Valley. Measurements of airborne particulate mass made with a beta attenuation monitor (BAM), an integrating nephelometer, and a continuous aerosol mass monitor (CAMM) were found to correlate well with reference measurements made with a filter-based sampler. A Dusttrak aerosol sampler overestimated airborne particle concentrations by a factor of approximately 3 throughout the study. Measurements of airborne particulate matter made with a tapered element oscillating microbalance (TEOM) were found to be lower than the reference filter-based measurements by an amount approximately equal to the concentration of NH4NO3 observed to be present in the airborne particles. The performance of the Dusttrak sampler and the integrating nephelometer was affected by the size distribution of airborne particulate matter. The performance of the BAM, the integrating nephelometer, the CAMM, the Dusttrak sampler, and the TEOM was not strongly affected by temperature, relative humidity, wind speed, or wind direction within the range of conditions encountered in the current study. Based on instrument performance, the BAM, the integrating nephelometer, and the CAMM appear to be suitable candidates for deployment in a real-time continuous PM2.5 monitoring network in central California for the range of winter conditions and aerosol composition encountered during the study.  相似文献   
435.
436.
Prenatal testing was performed in a 39-year-old Chinese pregnant woman referred for increased nuchal translucency measuring 5.7 mm. Non-invasive prenatal testing and SNP array study on amniotic fluid samples were normal. Whole exome sequencing (WES) was initiated further as the fetus had pericardial effusion of 1.2 mm, thickened myocardium over the right ventricular lateral wall and aberrant right subclavian artery. A detailed fetal echocardiogram also revealed persistent left superior vena cava and dilated coronary sinus at 20 weeks. From whole exome sequencing of the trio, a de novo heterozygous variant NM_005359.5(SMAD4): c.1499T>C (p.Ile500Thr) was detected. This pathogenic variant has been reported in the postnatal case cohort of Myhre syndrome. This condition is characterized by facial dysmorphism, intellectual disability, hearing loss, skeletal abnormalities and potential life threatening respiratory or cardiovascular manifestations. Termination of pregnancy was performed at 23 weeks. Small chins, pre-axial polydactyly, brachydactyly and clinodactyly were noted in the abortus. Ultrasound findings of increased nuchal translucency, thickened myocardium and pericardial effusion prompted further genetic evaluation for the prenatal diagnosis of Myhre syndrome by whole exome sequencing.  相似文献   
437.
Passive air sampling for nitrogen dioxide (NO(2)) and select volatile organic compounds (VOCs) was conducted at 24 fire stations and a compliance monitoring site in Dallas, Texas, USA during summer 2006 and winter 2008. This ambient air monitoring network was established to assess intra-urban gradients of air pollutants to evaluate the impact of traffic and urban emissions on air quality. Ambient air monitoring and GIS data from spatially representative fire station sites were collected to assess spatial variability. Pairwise comparisons were conducted on the ambient data from the selected sites based on city section. These weeklong samples yielded NO(2) and benzene levels that were generally higher during the winter than the summer. With respect to the location within the city, the central section of Dallas was generally higher for NO(2) and benzene than north and south. Land use regression (LUR) results revealed spatial gradients in NO(2) and selected VOCs in the central and some northern areas. The process used to select spatially representative sites for air sampling and the results of analyses of coarse- and fine-scale spatial variability of air pollutants on a seasonal basis provide insights to guide future ambient air exposure studies in assessing intra-urban gradients and traffic impacts.  相似文献   
438.
Medical waste management in Korea   总被引:2,自引:0,他引:2  
The management of medical waste is of great importance due to its potential environmental hazards and public health risks. In the past medical waste was often mixed with municipal solid waste and disposed of in residential waste landfills or improper treatment facilities (e.g. inadequately controlled incinerators) in Korea. In recent years, many efforts have been made by environmental regulatory agencies and waste generators to better manage the waste from healthcare facilities. This paper presents an overview of the current management practices of medical waste in Korea. Information regarding generation, composition, segregation, transportation, and disposal of medical wastes is provided and discussed. Medical waste incineration is identified as the most preferred disposal method and will be the only available treatment option in late 2005. Faced with increased regulations over toxic air emissions (e.g. dioxins and furans), all existing small incineration facilities that do not have air pollution control devices will cease operation in the next few years. Large-scale medical waste incinerators would be responsible for the treatment of medical waste generated by most healthcare facilities in Korea. It is important to point out that there is a great potential to emit air toxic pollutants from such incinerators if improperly operated and managed, because medical waste typically contains a variety of plastic materials such as polyvinyl chloride (PVC). Waste minimization and recycling, control of toxic air emissions at medical waste incinerators, and alternative treatment methods to incineration are regarded to be the major challenges in the future.  相似文献   
439.
Leaching tests of paraffin waste forms including boric acid, cobalt, strontium and cesium were performed to investigate the leaching characteristics of paraffin waste forms which had been generated in Korean nuclear power plants. The leaching tests were conducted according to ANSI/ANS-16.1 test procedure and the cumulative fractions leached (CFLs) of boric acid, cobalt, strontium and cesium were obtained. The compressive strength before and after the leaching test was measured for various waste forms with different mixing ratios of boric acid to paraffin. It was observed that boric acid and other nuclides immobilized within paraffin waste forms were congruently released and the leaching rates were influenced by reacted layer depth as the dissolution reaction progressed. A shrinking core model based on the diffusion-controlled dissolution kinetics was developed in order to simulate the test results. The CFLs and the leaching rates were well expressed by the shrinking core model and the cross-sectional view of specimen after the test demonstrated the applicability of this model with the shrinking dissolution front to the leaching analysis of paraffin waste forms.  相似文献   
440.
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