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101.
This study investigates the relationship between characteristics of environmental policy statements and the reputations of ISO 14001 registrars who had performed certification audits of firms operating in mainland China. Three characteristics of environmental policy statements were examined: (1) The conformance of the policy to strict interpretations of the international standard; (2) The policy statement's adherence to the good practice guidelines specified in ISO 14004; and, (3) Self-reported evaluations of the policy statement's effectiveness as implemented. Data from 106 facilities in Beijing, Shanghai and Guangzhou reveal that registrar quality has a relatively weak, positive relationship with conformance to both ISO 14001 standards and to ISO 14004 guidelines, but no relationship was observed with the self-reported data. Additional findings are that the use of foreign registrars is significantly associated with the adoption of ISO 14004 guidelines and that conformance with ISO 14001 standards is somewhat higher for international joint ventures and foreign-owned firms than for state-owned enterprises.  相似文献   
102.
Simultaneous removal of hydrogen sulfide (H2S) and ammonia (NH3) gases from gaseous streams was studied in a biofilter packed with granule activated carbon. Extensive studies, including the effects of carbon (C) source on the growth of inoculated microorganisms and gas removal efficiency, product analysis, bioaerosol emission, pressure drop, and cost evaluation, were conducted. The results indicated that molasses was a potential C source for inoculated cell growth that resulted in removal efficiencies of 99.5% for H2S and 99.2% for NH3. Microbial community observation by scanning electron microscopy indicated that granule activated carbon was an excellent support for microorganism attachment for long-term waste gas treatment. No disintegration or breakdown of biofilm was found when the system was operated for 140 days. The low bioaerosol concentration emitted from the biofilter showed that the system effectively avoided the environmental risk of bioaerosol emission. Also, the system is suitable to apply in the field because of its low pressure drop and treatment cost. Because NH3 gas was mainly converted to organic nitrogen, and H2S gas was converted to elemental sulfur, no acidification or alkalinity phenomena were found because of the metabolite products. Thus, the results of this study demonstrate that the biofilter is a feasible bioreactor in the removal of waste gases.  相似文献   
103.
Chung HH  Choi SW  Ok YS  Jung J 《Chemosphere》2004,57(10):1383-1387
Clays from tidal flat sediments showed efficient catalytic activity in the decomposition of PCE by gamma-radiation. The highest PCE removal of 98.6% was obtained with clays heated to 700 degrees C after acid treatment. The improved catalytic activity was identified by electron paramagnetic resonance (EPR) spectroscopy. The EPR spectra of clays were significantly changed by the acid and thermal treatments. The intensity of a narrow signal at g=2 (signal III) was decreased with increasing thermal treatment temperature and this increased the PCE removal efficiency. The acid treatment completely removed a broad signal at g=2 (signal II), decreased the intensity of signal III, and improved the gamma-radiation treatment of PCE.  相似文献   
104.
Nonequilibrium disc-flow techniques may better reproduce dynamic soil-pesticide interactions than traditional batch sorption studies. Batch kinetic and equilibrium experiments and dual-label thin-disc flow experiments were conducted with atrazine (6-chloro-N-ethyl-N'-isopropyl-1,3,5-triazine-2,4-diamine) and imazaquin [2-(4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl)-3-quinolinecarboxylic acid] using a Demopolis silt loam (loamy-skeletal, carbonatic, thermic, shallow Typic Udorthent; 8% clay, 62 g kg(-1) organic matter, 7.6 pH). Batch kinetic studies with both herbicides revealed an almost instantaneous rapid phase and a much slower gradual phase. The rapid phase was complete after 5 min and equilibrium was reached at 24 h. The rapid phase accounted for 74% and 12 to 30% of the total amounts adsorbed for atrazine and imazaquin, respectively. The sorption of both the rapid and 24-h isotherms for each herbicide best fit the Freundlich equation. The rapid and 24-h K(f) values of atrazine were 1.38 and 2.41, respectively, and the N value of both phases was approximately 0.93. For imazaquin, the rapid and 24-h K(f) values were 0.056 and 035, respectively, and the N value for the rapid phase of imazaquin was 0.71, compared with 0.86 for the 24-h isotherm. In the dual-label thin-disc flow experiments, the average partition coefficient for atrazine at the peak soil concentration point was 1.54. This value closely agreed with the observed rapid-phase K(f) value of 1.38. In contrast, the thin-disc flow experiments failed to detect any imazaquin retention. The thin-disc flow method can allow for a greater resolution of rapid sorption kinetics, which is impractical with batch studies. Along with dynamic partitioning data, the thin-disc flow method may provide kinetics data that may better complement environmental models than coefficients generated with batch techniques.  相似文献   
105.
A two-dimensional reservoir toxics model is essential to establishing effective water resources management and protection. In a reservoir, the fate of a toxic chemical is closely connected with flow regimes and circulation patterns. To better understand the kinetic processes and persistence and predict the dissipation of toxic contaminants in the reservoir during a spill or storm runoff event, a toxics submodel was developed and incorporated into an existing laterally integrated hydrodynamics and transport model. The toxics submodel describes the physical, chemical, and biological processes and predicts unsteady vertical and longitudinal distributions of a toxic chemical. The two-dimensional toxicant simulation model was applied to Shasta Reservoir in California to simulate the physico-chemical processes and fate of a volatile toxic compound, methyl isothiocyanate (MITC), during a chemical spill into the Sacramento River in 1991. The predicted MITC concentrations were compared with those observed. The effect of reservoir flow regimes on the transport and fate of the toxic substance was investigated. The results suggested that the persistence of MITC is significantly influenced by different flow regimes. Methyl isothiocyanate is more persistent in the reservoir under an interflow condition due to reduced volatilization from deep layers than under an overflow condition. In the overflow situation, the plume moved more slowly toward the dam and experienced greater dissipation. This analysis can assist in toxic spill control and reservoir management, including field sampling and closure of water intakes.  相似文献   
106.
BACKGROUND: Safety teams have become a popular means to recognize and prevent injuries in the workplace. In fact, organizations, such as OSHA, NIOSH, NIEHS, DOE, and the Ohio BWC, not only encourage safety teams, but have implemented them in their organizations. However, safety teams may not be legal as defined by NLRB Act Sections 2(5) and 8(a)(2). OBJECTIVE: To determine whether safety teams are illegal labor organizations. METHODS: A review of government regulations, safety programs, and safety teams was performed to create a framework of what types of safety programs/regulations are requested and/or required by a variety of government agencies. Next, these requirements were compared to existing case law on illegal labor organizations as defined by the NLRB. RESULTS: Most safety teams and programs, even those implemented by the Federal Government, are illegal labor organizations as defined by NLRB Act Sections 2(5) and 8(a)(2). CONCLUSIONS: The Federal Government needs to amend existing legislation and develop a revision of the NLRB Act that would allow safety teams to function legally in organizations without having to meet intrusive, constricting guidelines that may inhibit the value of safety teams. IMPACT ON INDUSTRY: Organizations must be aware that safety teams may be valuable in reducing job-related accidents and injuries but they may be illegal labor organizations.  相似文献   
107.
Lake Erie water quality has improved dramatically since the degraded conditions of the 1960s. Additional gains could be made, but at the expense of further investment and reductions in fishery productivity. In facing such cross-jurisdictional issues, natural resource managers in Canada and the United States must grapple with conflicting objectives and important uncertainties, while considering the priorities of the public that live in the basin. The techniques and tools of decision analysis have been used successfully to deal with such decision problems in a range of environmental settings, but infrequently in the Great Lakes. The objective of this paper is to illustrate how such techniques might be brought to bear on an important, real decision currently facing Lake Erie resource managers and stakeholders: the choice of new phosphorus loading targets for the lake. The heart of our approach is a systematic elicitation of stakeholder preferences and an investigation of the degree to which different phosphorus-loading policies might satisfy ecosystem objectives. Results show that there are potential benefits to changing the historical policy of reducing phosphorus loads in Lake Erie.  相似文献   
108.
Electrical resistance heating (ERH) is proving to be an effective technology to rapidly heat the subsurface and, in doing so, removing volatile organic compounds. Practitioners of this technology have observed that other processes (biodegradation, abiotic degradation, hydrolysis, and possibly others) occur to break down the chemicals of concern, and remediation is not solely accomplished through vaporization. Few sites treated using ERH have been monitored during and after treatment to identify and evaluate the processes occurring and assess the contribution of these other biological and chemical processes in the remediation effort so that they may be incorporated in the remediation design. At Fort Lewis, Washington, a landfill has been undergoing ERH treatment in three phases, where chlorinated volatile organic compounds represent the primary chemicals of concern in soil and groundwater. Other chemicals of concern include petroleum products, oils, and lubricants. The Fort Lewis remediation projects provided an opportunity to observe the reactions occurring in the subsurface during ERH and fine‐tune the study with each phase of operation. This study is still under way. However, the data gathered to date, which focuses on biodegradation, provides insights into the processes that have been observed. For the Fort Lewis site, biotic and abiotic degradation processes have been observed throughout the range of operating temperatures. At the lower temperature ranges (up to 70°C), biological processes appear to predominate. Above 70°C, abiotic processes become much more active. The goal of this work is to eventually optimize the use of these intrinsic processes in ERH remediation to reduce energy requirements and costs. © 2007 Wiley Periodicals, Inc.  相似文献   
109.
We examined the direct and moderated effects of an ability‐based measure of emotional intelligence (MSCEIT© V2.0) on individual performance in a sample of business undergraduates. Controlling for general mental ability and personality, emotional intelligence explained unique incremental variance in performance ratings on only one of two measures of interpersonal effectiveness (public speaking effectiveness). However, the interaction of emotional intelligence with conscientiousness explained unique incremental variance both in public speaking and group behavior effectiveness, as well as academic performance (cumulative GPA). We conclude that the effects of emotional intelligence on performance are more indirect than direct in nature. Individuals must not only have emotional intelligence, but also must be motivated to use it. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
110.
ABSTRACT: A three-year study has been conducted on a 4.6 mile stretch of the Saddle River near Lodi, New Jersey. The primary objectives of this investigation were (1) to provide baseline information on the concentration and distribution of heavy metals in bottom sediments of the Saddle River; (2) to qualitatively evaluate which parameters affect this distribution; and (3) to determine the effect of urbanization on the concentration and distribution of these materials. Significant enrichments of several heavy metals were observed in bottom sediments of the lower Saddle River near Lodi, New Jersey, as compared to the upper Saddle River. Attempts to correlate metal concentrations in bottom sediments with chemical-oxygen demand were not successful in demonstrating a relationship between these two factors. Metal concentrations were found to be strongly dependent upon particle size. In general, metal concentrations in bottom sediments increased with decreasing partical diameter. However, metals enrichment was observed to be considerably greater in the larger sediment fractions studied (>420μ) than the smaller sediment fractions as one proceeded downstream through the urban area. Since the larger sediment fractions are least effected by scour and transport they may best reflect the effect of urbanization on the distribution of heavy metals over an extended period of time at a given location.  相似文献   
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