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241.
Filtration of drinking water by point-of-use (POU) or point-of-entry (POE) systems is becoming increasingly popular in the United States. Drinking water is filtered to remove both organic and inorganic contaminants. The objective of this study was to evaluate the use of granular activated carbon from nutshells (almond, English walnut, pecan) in a POU water filtration system to determine its effectiveness in removing select, potentially toxic metal ions, namely, copper (Cu2+), lead (Pb2+) or zinc (Zn2+) found in drinking water. The nutshell-based carbon system was designated "Envirofilter" and was compared to four commercial POU systems with brand names of BRITA, Omni Filter, PUR and Teledyne Water Pik. Eight prototype "Envirofilters", consisting of individual or binary mixtures of carbons made from acid-activated almond or pecan shells and steam-activated pecan or walnut shells were constructed and evaluated for adsorption of the three metal ions. The results indicated that a binary mixture of carbons from acid-activated almond and either steam-activated pecan or walnut shells were the most effective in removing these metals from drinking water of all the POU systems evaluated. Binary mixtures of acid-activated almond shell-based carbon with either steam-activated pecan shell- or walnut shell-based carbon removed nearly 100% of lead ion, 90-95% of copper ion and 80-90% of zinc ion. Overall the performance data on the "Envirofilters" suggest that these prototypes require less carbon than commercial filters to achieve the same metal adsorption efficiency and may also be a less expensive product.  相似文献   
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Bingol EB  Ergun O 《Meat science》2011,88(4):774-785
Effects of various concentrations of O2/CO2 in modified atmosphere packaging on the microbiological quality and shelf-life of ostrich meat was investigated. Nine–12 months old ostriches were used. The iliofibularis muscle was cut into small cubes that were divided into five groups and then separately packaged under various gas mixes: air and O2:CO2:N2 ratios of 80:20:0, 60:20:20, 60:40:0, and 40:40:20, using 2 different headspace ratios (1:1 and 3:1). The packaged meats were kept at 4 °C for 10 days and were analysed microbiologically, physico-chemically and sensorially. As a result, the meat quality and shelf-life of ostrich meat under various gas compositions were improved; microbial growth was delayed due to high CO2 usage and shelf-life was increased by 5–7 days. However, an undesired loss of red colour of the ostrich meat may affect consumer acceptance.  相似文献   
244.
In this study, silk fabric samples were dyed by various procedures using Helichrysum arenarium extracts. Alum, ferrous sulfate, stanium chloride, calcium nitrate, and potassium bitartrate were used as mordants. Reversed‐phase high‐performance liquid chromatography with diode‐array detection was utilised for identification of the dyes present in the dyed silk fabrics and the plant extracts. The extraction of dyes was carried out with a hydrochloric acid/methanol/water (2:1:1 v/v/v) mixture. The colour coordinates and K/S values, as well as wash, light, and rub fastness, were determined.  相似文献   
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This paper proposes the upscaling of conventional individual bridge health monitoring problems into urban regions and transportation networks via mobile and smart sensing techniques together with an innovative reconnaissance procedure. The paper associates structural failure probabilities with systemic features and proposes decision criteria to optimize postdisaster actions. Twenty bridges constituting transportation network infrastructure compose the testbed region and utilize smartphone accelerometers for dynamics characterization in a vibration-based framework. In this framework, reconnaissance output serves for model development, and mobile sensor data enable finite element model updating. Structural reliability analyses merged in a chain setting generate the systemic behavior of cascaded bridge performance. Combining systemic reliability with transportation and health services demand, one can optimize the response strategies of the bridge population and strategize disaster-related decisions in a postevent assessment setting. Based on a testbed region with remote access to nearby vicinities, 18 earthquake scenarios are conducted to visualize the optimal evacuation strategies on the network, taking systemic bridge performance into consideration. Cost-free mobile sensing support adds one more fundamental information source for reducing the uncertainty of the models and, therefore, improves associated mitigation actions.  相似文献   
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Magnetic Resonance Materials in Physics, Biology and Medicine -  相似文献   
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