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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   
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The need for on-line information in any environment has led to the development of mobile satellite communication terminals. These high data-rate terminals require inertial antenna pointing error tolerance within fractions of a degree. However, the base motion of the antenna platform in mobile applications complicates this pointing problem and must be accounted for. Gimbaled motorised pedestals are used to eliminate the effect of disturbance and maintain uninterrupted communication. In this paper, a three-axis ship-mounted antenna on a pedestal gimbal system is studied. Based on the derived dynamic model of the antenna pedestal multi input-multi output PID and H linear controllers are designed to stabilise the antenna to keep its orientation unaltered towards the satellite while the sea waves disturb the antenna. Simulation results are presented to show the stabilisation performance of the system with the synthesised controllers. It is shown through performance comparison and analysis that the proposed H control structure is preferable over PID controlled system in terms of system stability and the disturbance rejection.  相似文献   
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This study introduces a comprehensive framework designed for detecting and mitigating fake and potentially threatening user communities within 5G social networks. Leveraging geo-location data, community trust dynamics, and AI-driven community detection algorithms, this framework aims to pinpoint users posing potential harm. Including an artificial control model facilitates the selection of suitable community detection algorithms, coupled with a trust-based strategy to effectively identify and filter potential attackers. A distinctive feature of this framework lies in its ability to consider attributes that prove challenging for malicious users to emulate, such as the established trust within the community, geographical location, and adaptability to diverse attack scenarios. To validate its efficacy, we illustrate the framework using synthetic social network data, demonstrating its ability to distinguish potential malicious users from trustworthy ones.  相似文献   
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K-feldspar and Na-feldspar exhibit similar mineralogical, chemical and surface properties. Froth flotation is known to be the only technique to enable their separation. Our earlier studies revealed a good selectivity in the presence of K+ and to a larger extent with Na+ ions. In this context, in order to further identify the role of Na+ ions in the selective separation of these minerals, ion selective electrodes were employed to determine the released Na and K ions released from albite and microcline into the solution and those adsorbed ions onto the mineral surfaces. Adsorption isotherms in feldspars/inorganic systems were constructed and the regions representing ion exchange and ion adsorption isotherms delineated. The mechanism of selective separation was elaborated on the basis of micro-flotation, solubility, adsorption and zeta potential measurements.  相似文献   
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In this study, polyvinyl alcohol (PVA) and boric acid (BA) were mixed in an aqueous medium by heating in order to prepare a PVA/BA hybrid material. The viscosity and pH values of the PVA/BA hybrid material mixed in various proportions were determined. Then the hybrid polymer was electrospun to give dimensions to fibers. The FT-IR spectra of these fibers revealed that BA chemically reacted with PVA and formed B–O–C bonds. The fibers were first calcified at 500 °C and then the calcified products were pelleted and exposed to the sintering process at 1300 °C. The XRD peaks of the sintered product were seen at 2θ = 34.7 and 37.7° verified the formation of boron carbide. The study proved that it was possible to use sub-micron fibers for the production of sub-micron boron carbide material.  相似文献   
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