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11.
In Marrakech, solid by-products from tanneries are highly polluting, generating large amounts of nitrogenous and organic matter. In the present study composting is tested as a cost-effective method for waste management to overcome many of the environmental hazards and produce a stable, rich material for soil fertilization. Two composting trials were conducted after neutralization by ammonia or lime. The aim of the neutralization was to avoid the antimicrobial effects of the acidity in the tannery waste, thus ensuring correct composting. Different techniques such as elemental analysis and 13C NMR spectroscopy were applied to analyse humic acids isolated from raw and composted materials, and to monitor the process of tannery waste composting, and the stability and maturity of the final product according to the means of neutralization. Comparison of data showed similar behaviour in both trials, but the composting process appeared to be more complete following neutralization with lime. The C, H and N content decreased, while the O increased. The FTIR and 13C NMR spectra show the decrease of aliphatic compounds demonstrated by the reduction of absorbance around 2922 cm−1 and of the resonance in the C-alkyl area around 0–55 ppm. The humic acids newly formed during composting were richer in the O–N alkyl and oxidized aromatic structures that increased almost twofold on composting after neutralization with lime. The first principal component axis PC1 (54%) separated C-aliphatic, C-carboxylic and other less stable and less polycondensed compounds such as polyphenols from the more polycondensed O–N alkyl and oxidized C-aromatic compounds.  相似文献   
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The possible involvement of lipid peroxidation (LPO) in the lead-induced inhibition of type I iodothyronine 5'-monodeiodinase activity (5'-D) has been worked out in chicken liver. Lead nitrate (1.5 mg per bird per day) for 30 days increased the lipid peroxidative process with a concomitant decrease in 5'-D activity in chicken liver. Also, a significant decrease in serum triiodothyronine (T3) concentration and an increase in serum thyroxine (T4) concentration were observed. The data suggest that lead-induced inhibition of type I 5'-D activity in chicken liver is mediated through the lipid peroxidative process.  相似文献   
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Burning dense, viscous combustibles such as heavy fuel‐oil as a water‐in‐oil emulsified combustible enables to decrease the emission of solid carbonaceous residue, in comparison with raw, non‐emulsified combustible. This is due to the phenomenon of micro‐explosion, meaning the rapid (<0.1 ms) vaporization of the water droplets inside the emulsion, breaking up the initial emulsion droplet into numerous and faster ‘daughter‐droplets’. The present work is based on a small‐scale furnace (300 kW max.) feed with heavy fuel‐oil mixed with 10–20% of gasoil, with and without emulsion of water. The emulsification of combustible enables to record a reproducible lowering in emission of carbonaceous residue from the combustion of emulsified fuel, in comparison with raw fuel. This is added to a variation in granulometry of carbonaceous residue, hereby considered as an indicator of second atomization. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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Wireless Networks - In Vehicular Ad-Hoc Networks, a link failure may occur due to non-optimal channel conditions, congestion or node mobility which causes data loss. Common proposed approaches try...  相似文献   
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Silicon - Herein, a pure and well crystallized Na-magadiite was synthesized by hydrothermal method. It was then used as a host matrix to prepare hybrid materials by intercalation of zwitterionic...  相似文献   
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This study examines the risk associated with oral contraceptive (OC) use in women with focal nodular hyperplasia (FNH). A total of 216 women (mean age, 36.2 years) with FNH were studied during 1989-98. The studied women were separated into five groups: no OC use (n = 28); high-dose OC use (50 mcg ethinyl estradiol, n = 46); low-dose OC use (30 mcg or less ethinyl estradiol, n = 98); low-dose and high-dose OC use (n = 33); pure progestagen use (n = 11). In each group, the mean diameter and the number of lesions per patient were assessed via magnetic resonance imaging (MRI). Findings revealed no differences between the five groups as to the number and the size of the lesions. The data showed that neither the intake nor the type of OC influenced the size and number of FNHs. A total of 128 women were followed up with serial MRI done after a mean of 23 months: 89 discontinued OCs, 14 remained without OCs, and 25 had taken or remained on low-dose OCs. In those who discontinued OCs, the FNH had decreased in size in two lesions and increased in size in one lesion. Despite continuation of OCs, the largest FNH disappeared 2 years after the first diagnosis, whereas the other FNH remained unchanged. Moreover, during this follow-up study, 12 women became pregnant; no increase in lesion size was seen during pregnancy. These findings indicate that low-dose OCs can be maintained in young women with FNH.  相似文献   
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We report on a patient with atypical clinical findings in whom magnetic resonance imaging confirmed the suspicion of penile rupture. The tear appeared as an obvious discontinuity of the low signal intensity of the tunica albuginea and was associated with a hematoma. We conclude that magnetic resonance imaging is useful for confirming the diagnosis of penile rupture when clinical findings are atypical, indicating surgical repair.  相似文献   
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