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991.
John Louis Parker 《环境索赔杂志》2017,29(3):242-252
Perflourinated compounds, or PFCs, have been widely used in our industrialized society. Notably, they are used in the manufacture of non-stick coated bakeware and in firefighting foams designed to fight high heat fires. These unregulated chemicals have gotten into surface and groundwater sources of drinking water in locations around the United States and likely the world. Data shows widespread release, particularly near airports and air bases and near industrial production sites.
PFCs cause many health related impacts. Human exposure pathways include perinatal transfer, consuming contaminated water, and consuming contaminated fish. Clean Water Act permitting programs can address their release into waterways. Contaminated site clean-up laws can also be used to remove the source contamination. Granular activated carbon technology can remove most forms of the chemicals from drinking water. The case study of drinking water contamination in Newburgh, New York illustrates the PFC challenge, public reaction, and government response. 相似文献
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Fashion, accessories, and homeware fall outside the regulations of Fairtrade Labelling Organizations International (FLO), which certifies mostly food products. A handful of fashion-led Fair Trade enterprises are now providing ranges of high-quality desirable products, made by workers employed in urban enterprises as well as independent producers in cooperatives. Tabeisa, an NGO involved in Fair Trade retailing, has developed a new regulatory framework which uniquely starts by defining the relations of production between all actors in the chain. This ensures that those not previously covered by existing standards are made visible and receive fair pay and conditions. 相似文献
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This article evaluates poverty transition using self-assessment in a quasi-experimental framework. Data are drawn from a survey conducted in 2006 of 400 women who were the beneficiaries of a poverty-alleviation programme which involved longer-term interventions towards building the strength of government departments, participating organisations, and beneficiaries. During the survey, when the project was approaching its conclusion, about 50 per cent of these farmers were still in the programme. The article addresses a number of key questions related to pathways out of poverty through livestock-based activities, heterogeneity in livelihood choice and its impact on household welfare, and wider applications. 相似文献
998.
Allgeier L Hemenway J Shirley N LaNier T Coyle HM 《Journal of forensic sciences》2011,56(5):1245-1249
The validity and feasibility of using DNA collection cards in the field for preservation and analysis of Cannabis sativa genotypes were investigated using a highly specific hexanucleotide marker. Collection cards were submitted to the National Marijuana Initiative, which selectively trained and managed the collection of specific types of samples from a variety of participating agencies. Samples collected at seizure sites included fresh marijuana leaf samples, dried "dispensary" samples, U.S. border seizures, and hashish. Using a standardized PCR kit with custom-labeled oligonucleotide primers specific to marijuana, collection cards produced eight genotypes and 13 different alleles, extremely low baselines, and no cross-reactivity with control plant species. Results were produced from all sample types with the exception of hashish. Plant DNA collection cards represent an easily implementable method for the genetic identification and relatedness of C. sativa street and grow site-seized samples with applications for databasing and market disruption. 相似文献
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Bond JW 《Journal of forensic sciences》2011,56(4):999-1002
From an examination of the fingerprint sweat corrosion of 40 different individuals on α phase brass, we show that an increase in visualization can be achieved by applying a negative potential to the brass followed by the introduction of a conducting powder. Previously, this technique has been demonstrated only for a positive applied potential and a corrosion product that was dominated by p-type copper (I) oxide. X-ray photoelectron and Auger electron spectroscopic analyses of the surface of the corroded brass show that an increase in visualization with a negative applied potential corresponds with an increase in the concentration of n-type zinc oxide relative to p-type copper (I) oxide with the Cu:Zn ratio <0.8:1. Work function conditions for the formation of an n-type zinc oxide/brass rectifying Schottky barrier are fulfilled. 相似文献
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Through a comparison of fingermark sweat corrosion of α phase brass in both the U.K. and Iraq, we show how samples from Iraq have improved fingermark corrosion over U.K. samples that require no additional enhancement prior to visualization. Over 50% of Iraqi samples produced fingermark corrosion with full ridge detail compared with 0% from the U.K. X-ray photoelectron spectroscopy analysis of the fingermark corrosion products showed that Iraqi samples exhibit more dezincification with the Zn:Cu ratio averaging 1:1.82 compared with 1:3.07 for U.K. samples. Auger spectroscopy showed the presence of both zinc oxide and copper (I) oxide. No copper (II) was observed on the surface of the corroded brass. Opportunities to exploit the optical properties of these thin film oxides to enhance the visualization of fingermark corrosion are considered, and the potential to use fingermark corrosion of metal as a means of visualizing fingerprints in war zones is discussed. 相似文献