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41.
This paper presents the potential applications of solar aggregate stockpiles intended for storing materials used in the production of hot mix asphalt. The stored materials are crushed stone, waste glass, and recycled asphalt. Three set‐ups, ie, models of solar stockpiles were made for testing, each having an equal volume, form, type and thickness of thermal insulation, and size of the opening through which sunlight is acting. The research aimed at determining the effects of exposure to sunlight on the temperature of the stored materials, the growth/loss of material temperature, the effects of different types of stored materials on the mixture temperature, and temperature loss in periods where there was no exposure to sunlight. The conclusions drawn from the analysis are that temperature stored in the stockpile material is affected by the duration of its exposure to the sunlight, the type of material stored, the way it is stored, and when it is stored.  相似文献   
42.
Usage of a multiple-arcs system has significantly improved process stability and coating properties in air plasma spraying. However, there are still demands on understanding and controlling the physical process to determine process conditions for reproducible coating quality and homogeneity of coating microstructure. The main goal of this work is the application of numerical simulation for the prediction of the temperature profiles at the torch outlet for real process conditions. Behaviour of the gas flow and electric arcs were described in a three-dimensional numerical model. The calculated results showed the characteristic triangular temperature distribution at the torch nozzle outlet caused by three electric arcs. These results were compared with experimentally determined temperature distributions, which were obtained with specially developed computed tomography equipment for reconstructing the emissivity and temperature distribution of the plasma jet close to the torch exit. The calculated results related to temperature values and contours were verified for the most process parameters with experimental ones.  相似文献   
43.
This paper presents a finite element time domain model for a numerical solution of a coupled non‐uniform transmission line problem. On the basis of the finite element method, a novel numerical procedure for the solution of a system of the non‐uniform multi‐conductor transmission line equations in the time domain is presented. The results obtained by the proposed method have been compared with the solution obtained using the finite difference time domain method, and an excellent correlation has been demonstrated. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
44.
Virgin olive oil (VOO) enriched with phospholipids (soy lecithin) up to the levels present in seed oils (from 2.5 to 10.0 g/kg) was studied as a potential functional food. Lecithin addition slightly increased the concentration of tocopherols and considerably increased K270 values. In the fatty acid composition, an increase of linoleic and a slight decrease of oleic acid were observed, as the decrease of monounsaturated/polyunsaturated fatty acid ratio. The radical-scavenging activity was evaluated by two methods: electron spin resonance spectroscopy using galvinoxyl free radical and VIS spectroscopy measurement of the disappearance of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical. Results indicate that lecithin addition retards the scavenging activity of VOO that is ascribed to the bipolar character of lecithin and its ability to entrap hydrophilic antioxidants. The effect of lecithin addition on the oxidative stability of VOO was evaluated by the Rancimat method, and a positive linear correlation (r = 0.9849) with induction time was found.  相似文献   
45.
Hypertension is one of the most prevalent and powerful contributors of cardiovascular diseases. Malignant hypertension is a relatively rare but extremely severe form of hypertension accompanied with heart, brain, and renal impairment. Resveratrol, a recently described grape-derived, polyphenolic antioxidant molecule, has been proposed as an effective agent in the prevention of cardiovascular diseases. This study was designed to examine chronic resveratrol administration on blood pressure, oxidative stress, and inflammation, with special emphasis on cardiac structure and function in two models of experimental hypertension. The experiments were performed in spontaneously (SHRs) and malignantly hypertensive rats (MHRs). The chronic administration of resveratrol significantly decreased blood pressure in both spontaneously and malignant hypertensive animals. The resveratrol treatment ameliorated morphological changes in the heart tissue. The immunohistochemistry of the heart tissue after resveratrol treatment showed that both TGF-β and Bax were not present in the myocytes of SHRs and were present mainly in the myocytes of MHRs. Resveratrol suppressed lipid peroxidation and significantly improved oxidative status and release of NO. These results suggest that resveratrol prevents hypertrophic and apoptotic consequences induced by high blood pressure with more pronounced effects in malignant hypertension.  相似文献   
46.
The research was conducted on days 60, 90, 120 and 150 during the lactation with the aim to determine the effect of lactation stage on the concentration of crucial elements and chemical composition in Croatian spotted goats' milk. Milk yield significantly decreased (from 1.15 to 0.76 kg/day), while the concentration of Ca, Mg, P, Zn and Mo in the milk of the goats significantly increased during lactation. The concentrations of Cr, Cd and Pb in milk were very low, with no significant deviations during lactation. The quality of milk from Croatian spotted goats is adequate compared with other breeds in the surrounding area of Croatia.  相似文献   
47.
The phenolic composition, antioxidant activity, and antimicrobial activity of extracts from vine leaves of six grape varieties collected in May, August, and September was studied. The phenolic potential of the extracts was dependent on variety and picking-time. Extracts of leaves collected in September were the richest in total phenols, flavonoids, flavonols, and stilbenes. The antioxidant properties determined by ferric reducing antioxidant power and 2,2-diphenyl-1-picrylhydrazyl assays, and antimicrobial activity against Stapylococcus aureus, Bacillus cereus, Campylobacter jejuni, Escherichia coli, and Salmonella Infantis were good and in correlation with the chemical composition changes of the leaf extracts. The results indicated that leaves remaining on the vine in September after the grape harvest could be especially promising as an inexpensive source of effective antioxidant/antimicrobial agents.  相似文献   
48.
This paper presents a numerical model of transmission line equations based on a combination of the finite element method and the generalized method of characteristics. A local system of the transmission line finite element is obtained using the generalized method of characteristics applied to the Telegrapher's equations. In this way, a spatial functional approximation using local shape functions together with the generalized trapezoidal rule used for time integration as it is done in the classical finite element formulation is avoided and higher accuracy of results is obtained. In order to show the essential principles of the proposed numerical method, for sake of simplicity, the scope of the paper is restricted to a single transmission line problem at the low frequency regime.  相似文献   
49.

The paper documents a concept of ocean forecasting system for ocean surface currents based on self-organizing map (SOM) trained by high-resolution numerical weather prediction (NWP) model and high-frequency (HF) radar data. Wind and surface currents data from the northern Adriatic coastal area were used in a 6-month long training phase to obtain SOM patterns. Very high correlation between current and joined current and wind SOM patterns indicated the strong relationship between winds and currents and allowed for creation of a prediction system. Increasing SOM dimensions did not increase reliability of the forecasting system, being limited by the amount of the data used for training and achieving the lowest errors for 4 × 4 SOM matrix. As the HF radars and high-resolution NWP models are strongly expanding in coastal oceans, providing reliable and long-term datasets, the applicability of the proposed SOM-based forecasting system is expected to be high.

  相似文献   
50.
Aeromonas species are becoming renowned as emerging pathogens by increasingly giving rise to a wide spectrum of food and waterborne infections in humans. Another worrisome feature of aeromonads is the growing frequency of antibiotic resistance as a consequence of their prominent diversity in terms of resistance determinants. This study aimed at determining the antimicrobial resistance pattern, prevalence and characterization of acquired β-lactamases, including extended-spectrum-β-lactamases (ESBLs) and AmpC cephalosporinases, as well as the presence of class 1 and 2 integrons, in Aeromonas isolates from wild-growing Mediterranean mussel (Mytilus galloprovincialis) of the eastern coast of Adriatic Sea, Croatia. Isolates were tested for susceptibility to 16 antibiotics and β-lactam/β-lactamase inhibitor combinations. Cephalosporin-resistant isolates were further screened by PCR for genes encoding AmpC (blaFOX, blaCMY, blaMOX, blaLAT, blaBIL, blaDHA, blaACC, blaMIR, blaACT), ESBLs (blaTEM, blaSHV, blaCTX-M, blaPER, blaVEB, blaGES/IBC, blaOXA) and integrases (intI1, intI2, intI3). Location of bla genes was characterized by plasmid DNA fingerprinting and Southern blot hybridization. Plasmids carrying ESBL genes were investigated for transferability by conjugation and PCR-based replicon typed. Out of 147 Aeromonas isolates recovered, 30 (20%) demonstrated multiple resistance profile, with co-resistance most frequently detected against penicillins, piperacillin/sulbactam and tetracycline. ESBL-encoding genes were detected in 21 (13 Aeromonas caviae and 8 Aeromonas hydrophila) isolates, with blaCTX-M-15 gene identified in 19 and blaSHV-12 in 12 isolates. Among them, 10 isolates simultaneously harboured blaCTX-M-15 and blaSHV-12, while 3 isolates additionally carried an AmpC β-lactamase blaFOX-2 gene. blaPER-1 gene was identified in a single isolate also harbouring the blaCTX-M-15 gene. While blaSHV-12 was chromosomally encoded, blaCTX-M-15 was located on conjugative IncFIB-type plasmids of ~ 40 kb in A. caviae isolates. IntI1 and intI2 genes were detected in 57.1% and 33.3% of ESBL-producing isolates.  相似文献   
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