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11.
Merih Ötker Uslu 《The Science of the total environment》2009,407(11):3450-3458
An integrated treatment method based on magnesium salt extraction followed by chemical oxidation was used for the treatment of a veterinary antibiotic, oxytetracycline (OTC) contaminated cow manure since animal manure can be an important source for antibiotic pollution in the environment. Pretreatment with magnesium salt enhanced the efficiencies of subsequent oxidation processes by extracting 63.9% of OTC from the manure thereby making it more favorable for oxidation with the hydroxyl radicals produced by the Fenton and ozone oxidation processes. Both the 24 h Fenton oxidation process with 434 mM H2O2 and 43.4 mM Fe2+ doses and the 1-h ozonation process with an applied ozone dose of 2.5 mg min− 1 provided more than 90% OTC removal from the manure slurry. However, the second-order OTC removal rate constant of Fenton process (119 M− 1s− 1) was remarkably lower than that obtained with the ozonation process (548 M− 1s− 1). The oxidant dose was a significant factor for the efficiency of the Fenton treatment but not for the ozone treatment. The efficiencies of both the Fenton and ozone oxidation processes were not affected by the pH adjustment of the manure slurry. 相似文献
12.
Ahmed Jamal Abdullah Al-Gburi Zahriladha Zakaria Merih Palandoken Imran Mohd Ibrahim A. A. Althuwayb Sarosh Ahmad Samir Salem Al-Bawri 《计算机、材料和连续体(英文)》2022,73(2):2785-2799
This article introduces a novel, ultrawideband (UWB) planar monopole antenna printed on Roger RT/5880 substrate in a compact size for small Internet of Things (IoT) applications. The total electrical dimensions of the proposed compact UWB antenna are 0.19 λo × 0.215 λo × 0.0196 λo with the overall physical sizes of 15 mm × 17 mm × 1.548 mm at the lower resonance frequency of 3.8 GHz. The planar monopole antenna is fed through the linearly tapered microstrip line on a partially structured ground plane to achieve optimum impedance matching for UWB operation. The proposed compact UWB antenna has an operation bandwidth of 9.53 GHz from 3.026 GHz up to 12.556 GHz at −10 dB return loss with a fractional bandwidth (FBW) of about 122%. The numerically computed and experimentally measured results agree well in between. A detailed time-domain analysis is additionally accomplished to verify the radiation efficiency of the proposed antenna design for the ultra-wideband signal propagation. The fabricated prototype of a compact UWB antenna exhibits an omnidirectional radiation pattern with the low peak measured gain required of 2.55 dBi at 10 GHz and promising radiation efficiency of 90%. The proposed compact planar antenna has technical potential to be utilized in UWB and IoT applications. 相似文献
13.
Unek IT Birlik M Cavdar C Ersoy R Onen F Celik A Camsari T 《Hemodialysis international. International Symposium on Home Hemodialysis》2005,9(4):344-348
A patient with end-stage renal disease presented with reflex sympathetic dystrophy syndrome (RSDS) on her left hand 1 month after arteriovenous fistula (AVF) surgery. Magnetic resonance angiography revealed steal syndrome at the AVF level. Bone scintigraphy revealed early-stage RSDS. We considered that arterial insufficiency because of steal phenomenon following AVF surgery and underlying occlusive arterial disease triggered RSDS development. 相似文献
14.
The efficiency of ozonation on the degradation of oxytetracycline, a veterinary antibiotic, has been investigated in both cow manure and synthetic animal feeding operation wastewater at varying experimental conditions. With a rapid degradation of antibiotic in synthetic wastewater, ozonation improved its biodegradability and eliminated bacterial toxicity caused by oxytetracycline. The degradation rate of oxytetracycline depended on pH and applied ozone dose, but not initial antibiotic concentration in wastewater. In the case of manure treatment, ozonation efficiency in terms of oxytetracycline degradation was negatively affected by moisture and antibiotic content of manure. The degradation rate of oxytetracycline in manure slowed down upon the extension of treatment time since ozone could not react with strongly adsorbed antibiotic on manure. Increase in humic and fulvic acid carbon and mineral nitrogen content was an indicator for the improvement of fertilizing value of manure by ozonation. 相似文献
15.
This article proposes a novel rectenna design based on modified Hilbert fractal shaped microstrip antenna and Villard voltage doubler rectifying circuit for RF energy harvesting applications operating at Global System for Mobile Communications (GSM) 900 MHz band. The energy harvesting antenna is numerically optimized and fabricated on a Rogers RO4003 substrate of thickness 1.52 mm with a compact overall physical sizes of 80 mm × 82 mm (λ0/4.16 × λ0/4.06). Various geometric parameters and circuit component values of the proposed energy harvesting system are optimized in order to achieve a matched input impedance with good radiation performance of high gain for the input power level less than ?20 dBm. The numerical and experimental results point out the technical potential of the proposed rectenna design to be utilized in DC power supply modules of low voltage, low power electronic devices. 相似文献
16.
This paper investigates the use of conditional demand analysis (CDA) method to model the residential end-use energy consumption at the national level. There are several studies where CDA was used to model energy consumption at the regional level; however the CDA method had not been used to model residential energy consumption at the national level. The prediction performance and the ability to characterize the residential end-use energy consumption of the CDA model are compared with those of a neural network (NN) and an engineering based model developed earlier. The comparison of the predictions of the models indicates that CDA is capable of accurately predicting the energy consumption in the residential sector as well as the other two models. The effects of socio-economic factors are estimated using the NN and the CDA models, where possible. Due to the limited number of variables the CDA model can accommodate, its capability to evaluate these effects is found to be lower than the NN model. 相似文献
17.
18.
An aeroelastic model for wind turbine blades derived from the unsteady Navier‐Stokes equations and a mode shape–based structural dynamics model are presented. For turbulent flows, the system is closed with the Spalart‐Allmaras turbulence model. The computation times for the aerodynamic solution are significantly reduced using the harmonic balance method compared to a time‐accurate solution. This model is significantly more robust than standard aeroelastic codes that rely on blade element momentum theory to determine the aerodynamic forces. Comparisons with published results for the Caradonna‐Tung rotor in hover and the classical AGARD 445.6 flutter case are provided to validate the aerodynamic model and aeroelastic model, respectively. For wind turbines, flutter of the 1.5 MW WindPACT blade is considered. The results predict that the first flapwise and edgewise modes dominate flutter at the rotor speeds considered. 相似文献
19.
An ultrathin dual‐layer flexible metamaterial absorber with triple‐band for RF energy harvesting applications has been reported in this article. The sub‐wavelength unit cell of the proposed absorber is composed of six distinct concentric annular having outer circumference of ring and octagonal inner circumference. The metallic resonators are constructed from copper foil self‐adhesive tape which are affixed on flexible neoprene rubber sheet terminated by metal ground plate. The proposed absorber prototype is ultrathin and compact with the thickness less than 0.037λ0 and cell size less than 0.2λ0 at the lower absorption frequency of 1.75 GHz. Flexible dual‐layer absorber exhibits triple absorption peaks of 96.91%, 96.41% and 90.12% at 1.75 GHz, 2.17 GHz and 2.6 GHz with full width at half maximum (FWHM) bandwidth of about ~6.5%. The RF performance of proposed absorber is numerically computed for different polarization and incidence angle variations. The absorption value is above 76% for the oblique incidence angle up to 45° in TE mode operation, whereas the absorption value is 94% for oblique incidence angle up to 60° in TM mode operation. The measured outcomes are in agreement with the numerically calculated results. The energy harvesting potential of the proposed absorber structure is numerically confirmed by the resulting improved RF absorption value in dependence to different resistive loading of the polarization insensitive unit cells. 相似文献
20.
Emre Topak Sviatoslav Voloshynovskiy Oleksiy Koval M. Kivanc Mihcak Thierry Pun 《Multimedia Systems》2005,11(2):121-132
In this paper we analyze performance of practical robust data-hiding in channels with geometrical transformations. By applying
information-theoretic argument we show that performance of a system designed based on both random coding and random binning
principles is bounded by the same maximal achievable rate for the cases when communication channel includes geometrical transformations
or not. Targeting to provide theoretic performance limits of practical robust data-hiding we model it using a multiple access
channel (MAC) with side information (SI) available at one of encoders and present the bounds on achievable rates of reliable
communications to such a protocol. Finally, considering template-based and redundant-based design of geometrically robust
data-hiding systems, we perform security analysis of their performance and present results in terms of number of trial efforts
the attacker needs to completely remove hidden information. 相似文献