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1.
This paper relies on Gjølberg’s national corporate social responsibility (CSR) index while its purpose is twofold. First, it seeks to extend the methodological instrument for assessing national CSR and, second, it applies the new approach to a much larger pool of countries (n = 86) in an attempt to provide a global CSR outlook. The emergent picture from the study is one of deficient CSR penetration and wide variation among countries where most of the assessed countries are still lagging in the endorsement of international CSR initiatives and schemes. Findings offer fertile ground to theorists and researchers for a deeper investigation of the national specificity of CSR and to further identify institutional determinants that shape the social responsiveness and self-regulation of business entities. The study has also implications for managers and top executives to consider as it infers that the national background can be influential in the development of a CSR agenda and can condition the level of CSR penetration.  相似文献   
2.
This article aims to describe the characteristics of collective working situations in complex systems – especially those in nuclear power plants – related to common forms of cooperation, in order to improve systems resilience. In addition, we will try to detail some aspects of collective working situations, emphasizing the differences between various forms of control. The similarities between work activities (multi-addressed messages, linkage to regulation, central and peripheral information) are nonetheless exposed. We conclude by proposing a contribution to support systems design, thus facilitating cooperation in teamwork activities.  相似文献   
3.
Photocatalytic degradation of dissolved organic carbon (DOC) by utilizing Fe(III)-doped TiO2 at the visible radiation range is hereby reported. The photocatalyst was immobilized on sintered glass frits with the coating done by wet method, calcinated at 500 °C and then applied in a photodegradation reactor. The addition of a transition metal dopant, Fe(III), initiated the red shift which was confirmed by UV–Vis spectroscopy, and the photocatalyst was activated by visible radiation. X-ray diffraction patterns showed that Fe(III) doping had an effect on the crystallinity of the photocatalysts. Mixtures of DOC and associated coloured solutions were degraded in first-order kinetics, showing that the degradation process was not dependent on intermediates or other species in solution. A reactor with a catalyst coating area of 12.57 cm2 was able to degrade 0.623 mg of the dissolved material per minute. Exposure of the reactor to hostile acidic conditions and repeated use did not compromise its efficiency. It was observed that the reactor regenerates itself in the presence of visible light, and therefore, it can be re-used for more than 100 runs before the performance dropped to <95 %. The results obtained indicate that the photocatalyst reactor has a great potential of application for use in tandem with biosorbent cartridges to complement water purification methods for domestic consumption.  相似文献   
4.
Fingerprinting of hydrocarbon products requires high resolution differentiation of individual hydrocarbon compounds in any mixture. This requires the applications of various measuring techniques. In this paper, we have chosen the heavy hydrocarbons in fuels, lubricants and paving material as examples to discuss the methods for chemical characterization and differentiation. In the category most frequently termed "semi-volatile hydrocarbons" with boiling points from about 500°F to 1200°F or higher, there are several families of hydrocarbons, both natural and refined that are not easily distinguished by conventional EPA tests. Among the groups which we will use as examples are asphalts, hydraulic fluid, transmission oil, motor lubricating oils, heating oils, crude oil and coal. These hydrocarbon families are best studied using combined gas chromatography-mass spectrometry in full scan mode and characterizing various homologous series of hydrocarbons at known fragment ions. The hydrocarbon series providing the best information are: (1) N -alkanes; (2) iso-alkanes; (3) steranes; (4) terpanes; (5) polynuclear aromatic hydrocarbons; (6) aromatic steranes; and (7) specific polycyclic compounds.  相似文献   
5.
Abstract

Environmental agencies are currently in the process of implementing a new air management program, which includes the improvement of fuel quality. In this work, exhaust emissions data and estimated relative risk for various fuels testing in-use vehicles, equipped with three different exhaust emission control technologies, are presented. Aromatics, sulfur, and olefins contents; type of oxygenated compound; and Reid vapor pressure were varied. The aim also includes calculating the ozone (O3)of forming potential and a relative cancer risk of emissions from current and formulated gasoline blends in Mexico. The proposed gasoline decreases carbon monoxide, total hydrocarbons (THC), and nitrogen oxides emissions by 18 and 14%, respectively, when compared with gasoline sold in the rest of the country and within ozone nonattainment metropolitan areas in Mexico, respectively.  相似文献   
6.
Accumulation and elimination of aqueous and dietary silver in Daphnia magna   总被引:1,自引:0,他引:1  
Lam IK  Wang WX 《Chemosphere》2006,64(1):26-35
The dissolved uptake, dietary assimilation, and efflux of Ag in a freshwater cladoceran, Daphnia magna, were measured under different laboratory conditions. The dissolved uptake rate of Ag was proportional to the ambient Ag concentration, but the accumulation was highly variable due to the sorption of Ag onto the daphnid bodies. The ambient Na(+) but not the ambient K(+) concentration significantly decreased the dissolved uptake of Ag, suggesting a competitive uptake of Ag(+) with Na(+). The dietary assimilation efficiencies (AEs) of Ag are dependent on the concentration of the algal food available to D. magna. The AE was as low as 2% when the food concentration reached the saturation levels. In contrast, the Ag concentrations in the algae did not significantly affect the Ag AE in D. magna. The efflux rate constant of diet-incorporated Ag was twice that through dissolved uptake. The elimination of Ag was further separated into different compartments (excretion, egestion, molting, and reproduction) in the juveniles and adults after accumulation from dissolved and dietary sources. Regeneration into the dissolved phase was the predominant pathway by which the incorporated Ag was lost from D. magna, regardless of the exposure pathway. In contrast to the essential metals or Hg, there was minimal maternal transfer of Ag from the mothers to the offspring. By employing the biokinetic model, we further showed that water is a dominant pathway for Ag accumulation in D. magna. Trophic transfer is less significant primarily because of the low Ag AE when the food concentration reached the saturation levels.  相似文献   
7.
The carbamazepine (CBZ) abatement is herein evaluated using catalytic ozonation at different NiO concentrations as catalyst: 100, 300, and 500 mg   相似文献   
8.
Three men were killed and four others were injured during a well drill operation on Hobson Well C-10A in the Sea Cliff Oil Field (also known as Rincon Oil Field), in Ventura County, California, United States, on August 10, 1994, as a result of errors made by the work supervisors at the site. The oil field was under management by Vintage Petroleum, Ltd., which was sued for negligence by the families of the deceased and injured. The coroner's autopsy examination concluded that the cause of the deaths was due to the inhalation of the toxic gas carbon monoxide (CO). This gas was assumed to have been released from the firing of high-energy guns (HEGs) using carbon-rich explosive pentaerythritol tetranitrate (PETN) in an oxygen-depleted environment, during a fracking operation by Schlumberger Corporation on Well C-10A. The author of this article was appointed as an expert witness by Schlumberger to evaluate if the coroner's conclusion was correct. A series of chemical analytical analyses were conducted on the vapor phase of samples, in addition to dissolved components in water from Well C-10A and two adjacent wells. Stable isotope analyses were also conducted on hydrogen (H2), methane (CH4), nitrogen (N2), CO, and water (H2O) 3 weeks after the accident, as well as on four additional occasions from September to December 1994. Control test analyses were performed on the products from HEG firings, using the same explosives as those used in the perforation of Well C-10A in control chambers at a Schlumberger facility in Houston, Texas. The conclusion reached was that the dominant products of PETN detonations are H2, CH4, CO, and N2. However, the isotope ratios (D/H and 13C/12C) of methane in the control experiments were different in Well C-10A, following the detonation on August 10, 1994, than those resulting from controlled PETN explosions. The conclusion reached in this study was that the fracking of the well at a depth of around 2,150 ft had increased the permeability of the sediment layers in the Padres Zone at that depth to allow the rapid release of a large quantity of natural gas, primarily CH4, which supersaturated the water in the well. This event caused the formation of a large bubble, which ballooned out of the well to the surface, displacing air in the location where the men were working, and thus causing asphyxiation, which resulted in the death of the three men. The judge accepted this interpretation.  相似文献   
9.
In the present work, the adsorption capacity of anthill was investigated as a low‐cost adsorbent to remove the heavy metal ions, lead (II) ion (Pb2+), and zinc (II) ion (Zn2+) from an aqueous solution. The equilibrium adsorption isotherms of the heavy metal ions were investigated under batch process. For the study we examined the effect of the solution's pH and the initial cations concentrations on the adsorption process under a fixed contact time and temperature. The anthill sample was characterized using a scanning electron microscope (SEM), X‐ray fluorescence (XRF), and Fourier transform infrared (FTIR) techniques. From the SEM analysis, structural change in the adsorbent was a result of heavy metals adsorption. Based on the XRF analysis, the main composition of the anthill sample was silica (SiO2), alumina (Al2O3), and zirconia (ZrO2). The change in the peaks of the spectra before and after adsorption indicated that there was active participation of surface functional groups during the adsorption process. The experimental data obtained were analyzed using 2‐ and 3‐parameter isotherm models. The isotherm data fitted very well to the 3‐parameter Radke–Prausnitz model. It was noted that Pb2+ and Zn2+ can be effectively removed from aqueous solution using anthill as an adsorbent.  相似文献   
10.
This paper describes and analyses the public health system response to the deadly earthquake in Sichuan province, China, in May 2008. Drawing on an experiential learning project consisting of a literature review and field research, including a series of interviews with medical and public health professionals, policy‐makers and first responders, a conceptual framework was developed to describe the response. This approach emphasises the pre‐existing preparedness level of the medical and public health systems, as well as social, economic and geo‐political factors that had an impact on mitigation efforts. This framework was used to conduct post‐disaster analyses addressing major response issues and examining methods employed during the public health response to the disaster. This framework could be used to describe and analyse the emergency response to other disasters.  相似文献   
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