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671.
This paper examines the relationship between environmental compliance and financial performance of large US companies. The environmental performance is measured in penalties assessed for violations of environmental regulations. The financial performance is represented by the profit margins. The regression models developed in this paper suggest that the degrees of environmental compliance have a positive influence on the profit margins. Conventional economic wisdom is that regulations impose costs and restrictions and therefore put companies at a competitive disadvantage. However, this paper is consistent with the proponents of environmental regulations who argue that tough regulations force companies to be innovative and as a result make them more productive.  相似文献   
672.
Carrier agent as one of the synthetic persistent molecules present in textile effluents considered as one of the most highly toxic, carcinogenic and serious inhibitor of the microbial respirometric activity. This chemical is used as accelerants in the dyeing or printing the hydrophobic fibers by dispersed dyes. Hydrophobic polypropylene (PP) fibers cannot be dyed by conventional dyeing process due to the absence of dye sites in the molecular chain and their high crystallinity. This study presents a carrier-free exhaust dyeing as an environmentally friendlier and cleaner process. In order to produce dyeable PP fibers, the PP was blended and melt spun with poly(butylene terephthalate) (PBT) at various ratios. First PP and PBT granules at blend ratios of 5, 10, 20, 30, 40 percent of PBT dispersed phase were physically mixed then the melt spinning of blended samples was carried out by a Maddock mixing zone extruder. The results showed that suitable exhaust dyeing process without using any carrier agents was possible for all PP/PBT alloy fiber samples. The dye uptake of samples significantly increased by increasing the PBT dispersed phase content. By increasing the PBT dispersed phase content decrease in the crystallinity percent resulting in significant enhancement in dye uptake of the alloy fiber samples was observed. A degree of four polynomial equation for dye uptake against blend ratio was obtained by which the optimum blend ratio was 72/28 percent of PP/PBT alloy fiber composition. In all alloy fiber dyed samples uniform coloration was observed. No considerable changes in the mechanical properties for dyed samples against undyed samples were observed. Interestingly, the best mechanical property among alloy fiber samples was observed in the sample containing 30 percent PBT dispersed phase which approximately corresponds to optimum blend ratio gained from mathematical calculations. In all PP/PBT alloy fiber samples strong fastness to soaping and very good to excellent fastness to light were achieved.  相似文献   
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674.
Growth responses of herbaceous mimosa (Mimosa strigillosa Torr. and Gray), a potential new reclamation species in the SE USA and Mexico, to nine soil pH scales were studied under a controlled environment at Nacogdoches, TX, USA. Twenty seeds were planted in each of 40 (nine scales plus one control in four replicates) 20.3-cm pots filled with Tonkawa sandy soil. These pots were treated with H2SO4 or Ca(OH)2 to adjust each pot to its designated pH level. After 15 days of seeding, the emergence rate was at best about 50–70% for pH 4.7–6.6. The plant can survive and grow at soil pH as low as 4.7, but the optimum growth seems to be on soils with pH ranging from 6.2 to 7.1. At this pH range, the plant exhibits higher values of green and dry biomass, longer shoot growth and lower root/shoot weight and length ratios. The survival rate was greater than 90% for all treatments, except for pH 4.1. There were no nutrient deficiencies in plant tissues on soil pH 4.7 or higher. The plant allocated more growth to the shoot under optimum conditions, but more growth to the roots under environmental stress. It is not suitable for herbaceous mimosa to grow on soils with pH 4.1 or less.  相似文献   
675.
676.
Journal of Polymers and the Environment - The effect of long term immersion in seawater at different temperatures on the properties of pultruded glass fibre reinforced polymer (GFRP) composite...  相似文献   
677.
Sustainable development is a process which aims at establishing a harmonious relationship between man, on the one hand, and environmental and natural resources, on the other, capable of coping with ever-increasing changes and challenges over time. This paper investigates, in a conceptual and qualitative manner, the practices and procedures of sustainable development in Jordan and outlines constraints and difficulties facing Jordan in pursuing such development. The paper concludes with a presentation of some prerequisites for the process in the light of the national objectives and suggests recommendations for future action.  相似文献   
678.
Environmental Geochemistry and Health - Sediment can accumulate trace elements in the environment. This study profiled the magnitude of As, Ba, Cd, Co, Cu, Cr, Ni, Pb, Se, and Zn pollution in...  相似文献   
679.
Sorption characteristics of the Benzimidazole fungicide Carbendazim were assessed in seven different soils using batch equilibrium method and analysed by UV-Vis spectrophotometer. The values of adsorption co-efficient Kd ranged from 14.3 to 39.8?µg/mL depending upon unique physiochemical properties of soils. Negative values for Gibbs free energy (ΔG) proposed an exothermic and low interaction between Carbendazim and soil samples leading to physiosorption. Statistical analysis showed a negative correlation of soil pH and Kd (R2= ?0.80) and a positive correlation with organic matter (R2?=?0.77). Activated carbon prepared from Arachis hypogaea (peanut shells) by acid activation for Carbendazim removal from soils was characterised by FTIR spectrometry, indicating the change in functional groups. The highest percentage removal observed was 70% in 5?ppm initial Carbendazim concentration while 65% in 7.5?ppm concentration. This method can be implied in agricultural soils as an efficient and cheap technique for removing the hazardous pesticides from the environment.  相似文献   
680.
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