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101.
The effects of the operating conditions, the initial concentrations of marine diesel fuel (MDF) and the coexisting Pb in the soil, and the ethylene diamine tetra acetic salt (EDTA) in solution on MDF removal by sodium dodecyl sulfate (SDS) washing were extensively investigated with the aim of optimizing the process parameters and determining the MDF removal efficiency by SDS under different contamination conditions. The experimental results from batch tests indicated that the majority of MDF was removed by SDS in the first 2?h, and its optimal pH was nearly neutral. Increasing the SDS concentration linearly increased the MDF removal efficiency. At a given SDS concentration, the removal efficiency was dependent on the existing forms of MDF in soils, and the free phase of MDF was found to be more easily removed than the adsorbed phase. MDF removal by SDS was significantly reduced by the coexisting Pb in soils, which likely forms a complexation with SDS and thereby enhances the partitioning of MDF in the soil by the re-adsorption of released MDF onto the hydrophobic tails of the adsorbed SDS. EDTA alone, or with SDS, could remove MDF, but the remaining MDF in the contaminated soil after EDTA washing became more difficult to be removed by SDS. Therefore, the EDTA washing followed by SDS washing is not recommended for MDF removal. 相似文献
102.
Complex nonconstant envelope high-order digital modulation schemes used in modern communication satellites bring new requirements for the linearity and power efficiency of the on-board traveling-wave tubes (TWTs). As a result, a reassessment of typical TWT specifications is required. A digital system-level figure-of-merit, the total degradation, is proposed. It accounts for the characteristics of any coded signaling scheme, as well as for the performance of the overall communications link, including cochannel and adjacent channel interference. This figure-of-merit allows for reoptimizing the operating point of currently used TWTs, comparing the end-to-end performance of different tubes, and revising the standard TWT linearity-versus-efficiency requirements based on carrier-to-third-order-intermodulation (IM) ratio (C/IM3), noise power ratio, and carrier-to-noise-plus-IM ratio [C/(N + I)]. 相似文献
103.
Moderate consumption of red wine provides beneficial effects to health. This is attributed to polyphenol compounds present in wine such as resveratrol, quercetin, gallic acid, rutin, and vanillic acid. The amount of these antioxidants is variable; nevertheless, the main beneficial effects of red wine are attributed to resveratrol. However, it has been found that resveratrol and quercetin are able to photosensitize singlet oxygen generation and conversely, gallic acid acts as quencher. Therefore, and since resveratrol and quercetin are some of the most important antioxidants reported in red wines, the aim of this research was to evaluate the photosensitizing ability of 12 red wine extracts through photo‐oxidation of ergosterol. The presence of 1O2 was detected by ergosterol conversion into peroxide of ergosterol through 1H NMR analysis. Our results showed that 10 wine extracts were able to act as photosensitizers in the generation of singlet oxygen. The presence of 1O2 can damage other compounds of red wine and cause possible organoleptic alterations. Finally, although the reaction conditions employed in this research do not resemble the inherent conditions in wine making processing or storing, or even during its consumption, this knowledge could be useful to prevent possible pro‐oxidant effects and avoid detrimental effects in red wines. 相似文献
104.
Factors affecting bulk to total bacteria ratio in drinking water distribution systems 总被引:1,自引:0,他引:1
Bacteria in drinking water systems can grow in bulk water and as biofilms attached to pipe walls, both causing regrowth problems in the distribution system. While studies have focused on evaluating the factors influencing the bacteria in bulk water and in biofilms separately, there is a need for understanding biofilm characteristics relative to the bulk water phase. The current study evaluated the effects of chlorine and residence time on the presence of culturable bacteria in biofilms relative to that in bulk water. The results showed that when no chlorine residual was present in the system, the median ratio of bulk to total bacteria was 0.81, indicating that 81% of the bacteria were present in bulk water, whereas only 19% were present in the biofilm. As chlorine concentration increased to 0.2, 0.5, and 0.7 mg/L, the median percentage of bacteria present in bulk water decreased to 37, 28, and 31, respectively. On the other hand, as the residence times increased to 8.2, 12, 24, and 48h, the median percentage of bacteria present in bulk water increased to 7, 37, 58, and 88, respectively, in the presence of a 0.2mg/L chlorine residual. The common notion that biofilms dominate the distribution system is not true under all conditions. These findings suggest that bulk water bacteria may dominate in portions of a distribution system that have a low chlorine residual. 相似文献
105.
Luis Martínez Irene Cilla José Antonio Beltrán Pedro Roncalés 《Journal of food science》2006,71(1):S48-S53
ABSTRACT Capsicum annuum (red sweet and hot cayenne) and Piper nigrum (black and white) pepper powders were evaluated for inhibition of oxidative reactions and extension of the shelf life of fresh pork sausages packaged in a modified atmosphere. Sausages containing either red sweet pepper or cayenne pepper (0.1%, 0.5%, or 2%) or black or white pepper (0.1%, 0.5%, or 1%) were packaged in a modified atmosphere of 80% O2+ 20% CO2, stored for 16 d in the dark at 2 °C, and analyzed each 4 d for pH, CIE L*, a*, and b*, 2‐thiobarbituric acid‐reactive substances (TBARS), psychrotrophic aerobes, sensory discoloration, and off‐odor. Results demonstrated that Capsicum peppers (sweet red and hot cayenne) enhanced red color but failed to prevent discoloration, whereas they were very effective in inhibiting lipid oxidation, chiefly at the highest concentration used (2%), which resulted in a delay of off‐odor formation. Piper peppers (black and white) significantly delayed discoloration with small modification of sausage color; furthermore, they also inhibited lipid oxidation, which led to a delay of off‐odor formation, particularly in the form of black pepper. Besides this, all those spices inhibited microbial growth when added at the highest concentration (1%Piper and 2%Capsicum). 相似文献
106.
C. Bustreo G. Casini G. Zollino T. Bolzonella R. Piovan 《Fusion Engineering and Design》2013,88(12):3141-3151
FRESCO (Fusion REactor Simplified COsts) is a code based on simplified models of physics, engineering and economical aspects of a TOKAMAK-like pulsed or steady-state fusion power plant. The experience coming from various aspects of ITER design, including selection of materials and operating scenarios, is exploited as much as possible.Energy production and plant power balance, including the recirculation requirements, are derived from two models of the PPCS European study, the helium cooled lithium/lead blanket model reactor (model AB) and the helium cooled ceramic one (model B). A detailed study of the availability of the power plant due, among others, to the replacement of plasma facing components, is also included in the code.The economics of the fusion power plant is evaluated through the levelized cost approach. Costs of the basic components are scaled from the corresponding values of the ITER project, the ARIES studies and SCAN model. The costs of plant auxiliaries, including those of the magnetic and electric systems, tritium plants, instrumentation, buildings and thermal energy storage if any, are recovered from ITER values and from those of other power plants.Finally, the PPCS models AB and B are simulated and the main results are reported in this paper. 相似文献
107.
Irene Peinado Isabel Moya Laura García-Valverde Raquel Francs Rosana Ribes Patrocinio Polo María Jos Gmez-Torres Ana Monz 《International journal of molecular sciences》2023,24(1)
How does the in vitro maturation (IVM) medium and the vitrification procedure affect the survival of germinal vesicle (GV) oocytes obtained from stimulated cycles and their development to the blastocyst stage? In total, 1085 GV human oocytes were obtained after women underwent a cycle of controlled ovarian stimulation, and these oocytes were subjected to IVM before or after their vitrification. IVM was carried out in two commercial culture media not specifically designed for maturation. MII oocytes were then activated and embryo development until day 6 was evaluated. According to the results, a higher percentage of oocytes reach the MII stage if they are vitrified before they undergo IVM. Nevertheless, the medium used and the sample size determine whether these differences become significant or not. Similar survival rates and development to blastocysts were observed in all the conditions studied. 相似文献
108.
Valente P Forastiere F Bacosi A Cattani G Di Carlo S Ferri M Figà-Talamanca I Marconi A Paoletti L Perucci C Zuccaro P 《Tobacco control》2007,16(5):312-317
Background
A smoking ban in all indoor public places was enforced in Italy on 10 January 2005.Methods
We compared indoor air quality before and after the smoking ban by monitoring the indoor concentrations of fine (<2.5 μm diameter, PM2.5) and ultrafine particulate matter (<0.1 μm diameter, UFP). PM2.5 and ultrafine particles were measured in 40 public places (14 bars, six fast food restaurants, eight restaurants, six game rooms, six pubs) in Rome, before and after the introduction of the law banning smoking (after 3 and 12 months). Measurements were taken using real time particle monitors (DustTRAK Mod. 8520 TSI; Ultra‐fine Particles Counter‐TRAK Model 8525 TSI). The PM2.5 data were scaled using a correction equation derived from a comparison with the reference method (gravimetric measurement). The study was completed by measuring urinary cotinine, and pre‐law and post‐law enforcement among non‐smoking employees at these establishmentsResults
In the post‐law period, PM2.5 decreased significantly from a mean concentration of 119.3 μg/m3 to 38.2 μg/m3 after 3 months (p<0.005), and then to 43.3 μg/m3 a year later (p<0.01). The UFP concentrations also decreased significantly from 76 956 particles/cm3 to 38 079 particles/cm3 (p<0.0001) and then to 51 692 particles/cm3 (p<0.01). Similarly, the concentration of urinary cotinine among non‐smoking workers decreased from 17.8 ng/ml to 5.5 ng/ml (p<0.0001) and then to 3.7 ng/ml (p<0.0001).Conclusion
The application of the smoking ban led to a considerable reduction in the exposure to indoor fine and ultrafine particles in hospitality venues, confirmed by a contemporaneous reduction of urinary cotinine. 相似文献109.
Carmen de Jesús-Gil Lídia Sans-de San Nicols Ester Ruiz-Romeu Marta Ferran Laura Soria-Martínez Irene García-Jimnez Anca Chiriac Josep Manel Casanova-Seuma Josep Manel Fernndez-Armenteros Sherry Owens Antonio Celada Michael D. Howell Ramn María Pujol Luis Francisco Santamaria-Babí 《International journal of molecular sciences》2021,22(4)
Candida albicans (CA) infections have been associated with psoriasis onset or disease flares. However, the integrated immune response against this fungus is still poorly characterized in psoriasis. We studied specific immunoglobulins in plasma and the CA response in cocultures of circulating memory CD45RA− cutaneous lymphocyte antigen (CLA)+/− T cell with autologous epidermal cells from plaque and guttate psoriasis patients (cohort 1, n = 52), and also healthy individuals (n = 17). A complete proteomic profile was also evaluated in plaque psoriasis patients (cohort 2, n = 114) regarding their anti-CA IgA levels. Increased anti-CA IgA and IgG levels are present in the plasma from plaque but not guttate psoriasis compared to healthy controls. CA cellular response is confined to CLA+ T cells and is primarily Th17. The levels of anti-CA IgA are directly associated with CLA+ Th17 response in plaque psoriasis. Proteomic analysis revealed distinct profiles in psoriasis patients with high anti-CA IgA. C-C motif chemokine ligand 18, chitinase-3-like protein 1 and azurocidin were significantly elevated in the plasma from plaque psoriasis patients with high anti-CA levels and severe disease. Our results indicate a mechanism by which Candida albicans exposure can trigger a clinically relevant IL-17 response in psoriasis. Assessing anti-CA IgA levels may be useful in order to evaluate chronic psoriasis patients. 相似文献
110.
Backwash procedures for deep bed filters were evaluated and compared by means of a new integrated approach based on productivity. For this, different backwash procedures were experimentally evaluated by using a pilot plant for direct filtration. A standard backwash mode as applied in practice served as a reference and effluent turbidity was used as the criterion for filter run termination. The backwash water volumes needed, duration of the filter-to-waste period, time out of operation, total volume discharged and filter run-time were determined and used to calculate average filtration velocity and average productivity. 相似文献