Search

The ocean covers 70% of the earth’s area, and the seawater uranium is more than 1000 times that of terrestrial uranium ore. In order to increase the power generation and ensure the sustainable operation of nuclear power plants, the development of unconventional uranium resources is of great significance. As an effective means to solve shortage of terrestrial uranium resources, uranium extraction from seawater has received extensive attention in recent years. At present, many methods including membrane separation, chemical deposition, solvent extraction, ion exchange, reduction and adsorption have been applied to uranium extraction from seawater. This paper focuses on the recent research progress of adsorption method used inorganic materials, organic materials, carbon materials as adsorbent, and emerging electroreduction technologies, and further discusses the challenges and opportunities of these two methods.

Monodispersed and spherical gold nanoparticles and over nanoparticles with average is about 50 nm and 45 nm respectively, were synthesized by chemical reduction method using gearing as the protective agents, chioroauric aid SOUSE and over nitrate as metal source, hydrant hydrate as riding agents. UV-vis spectrum (UV-vis), X-ray powder diffraction ( XRD), flourier transform mortared spectrometer (FT-IR)and scorning electron microscope (SEM)were used to check the as-prepared gold and over nanoparticles. Some influencing factors nan the process of preparation of gold and over nanoparticles are briefly discussed. The results show that the prepared gold and over nanopaerieles are small Nan is with narrow distriburion. The amounts of precursor soon, reducing agent and gelatin solution play important roles in the size and morphologies of gold and silver nanoparticles. As the amount of precursor solution, reducing agents and gelatin solution increased, the particles size showed a trend of first decreasing and then increasing. The optimized processing parameters nan this research for preparation of gold and silver nanoparticles can be obtained when the consumption of gelatin solution, precursor solution, and redoing agent is 5,2 and 2 mL,respectively. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University (Science Edition) is the property of Journal of Zhejiang University (Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Wool Textile Journal is the property of National Wool Textile Science & Technology Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper is devoted to design the time-delayed controller using direct acceleration feedback for active vibration control systems. By means of the reduction method and the output state-derivative feedback control approach, a new continuous time-delayed acceleration feedback controller is proposed without the inclusion of the displacement and velocity signal, so that the accumulation errors caused by once and twice integration of the acceleration signal can be avoided. In order to cater for the requirement of computer control, the discrete form of the proposed controller is obtained by the discretization of the corresponding integral system equation. The developed time-delayed feedback controller is examined by the computer simulation, with a special focus on the control performance of a cantilever beam with the piezoelectric actuator and the acceleration sensor. Simulation results demonstrate that the proposed controller can effectively reduce the free vibration response of the intelligent cantilever beam, and compared with the acceleration feedback controller, it has wider parametric stable intervals and better control effects. In addition, the proposed controller exhibits good robustness to the inaccuracy of the estimated time delay of the controlled system. [ABSTRACT FROM AUTHOR]