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41.
Mechanochemical sulfidization of a mixed sulfide/oxide copper ore by co-grinding with sulfur and additives including Mg(NO3)2 and Fe(NO3)3 salts and iron, aluminum and magnesium powders was investigated for the first time. Also, the influence of sulfidization during the wet-milling process was examined on the separation efficiency and recovery of copper in detail. The results demonstrated that co-grinding with sulfur solely had the best flotation performance at the value of 0.5 wt.% and it was attributed to the possible existence of S-O bonding on copper oxides surfaces. In addition, adding magnesium nitrate salt, magnesium powder, iron nitrate salt and aluminum powder as additive associated with 0.5 wt% sulfur into ball milling caused the flotation improvement at the amounts of 0.2 wt%, 0.2 wt%, 0.5 wt% and 0.5 wt%, respectively. Also, the effect of grinding time and sulfidization pH with 0.5 wt% sulfur solely was determined and pHs of 7.5 to 8.5 gave the best results. The highest recovery (75.76%) and separation efficiency (63.44%) were achieved at pH of 7.5 and 8.5, respectively. 相似文献
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Drug‐loaded microparticles prepared by the one‐step deposition of calcium carbonate/alginate onto cotton fabrics 下载免费PDF全文
Huan‐Ling Wu Xiao‐Xiao Hou Christopher Branford‐White Xiao‐Zhu Sun Lei Tao Syeda Um‐I‐Zahra Li‐Min Zhu 《应用聚合物科学杂志》2015,132(40)
Calcium carbonate (CaCO3)/alginate inorganic–organic hybrid particles were synthesized and deposited on to the surface of cotton fabrics with a novel one‐step procedure. The effects of the Ca2+/CO32?/alginate molar ratio on the cotton matrix were investigated. The optimization of the process resulted in a regular shaped hybrid microparticles, and scanning electron microscopy revealed that the particles were uniformly distributed on the surface of the fibers. Dynamic light scattering showed that the particles were about 2 μm in diameter. Moreover, transmission electron microscopy images demonstrated that the core–shell structure of the particles existed along with CaCO3 evenly enfolded into the alginate layer. An X‐ray diffraction pattern displayed that the alginate/CaCO3 hybrid microparticles were a mixture of calcite and vaterite crystal. Fourier transform infrared spectroscopy indicated that CaCO3/alginate hybrid particles formed in situ were the only deposited materials. The thermogravimetric analysis curve indicated a certain mass ratio of the alginate and CaCO3 in the hybrid particles. Furthermore, the drug‐loading and drug‐release properties of the hybrid microspheres were studied, and the results show that the water‐soluble diclofenac sodium could be effectively loaded in the hybrid microparticles and the drug release could be effectively sustained. Finally, both of the microparticles and modified fabrics had good cytocompatibility. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42618. 相似文献
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Scientometrics - We analyzed breakthrough patents that serve as the basis of emerging technological trajectories and paradigm over 25-years. The results showed that although technological fields... 相似文献
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Zahra Azimi Aswani Gopakumar Amira S.Ameruddin Li Li Thien Truong Hieu T.Nguyen Hark Hoe Tan Chennupati Jagadish Jennifer Wong-Leung 《Nano Research》2022,(4):3695-3703
Catalyst-free InGaAs nanowires grown by selective area epitaxy are promising building blocks for future optoelectronic devices in the infrared spectral region.D... 相似文献
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Alireza Ahmadiparidari Robert E. Warburton Leily Majidi Mohammad Asadi Amir Chamaani Jacob R. Jokisaari Sina Rastegar Zahra Hemmat Baharak Sayahpour Rajeev S. Assary Badri Narayanan Pedram Abbasi Paul C. Redfern Anh Ngo Mrton Vrs Jeffrey Greeley Robert Klie Larry A. Curtiss Amin Salehi‐Khojin 《Advanced materials (Deerfield Beach, Fla.)》2019,31(40)
Lithium–CO2 batteries are attractive energy‐storage systems for fulfilling the demand of future large‐scale applications such as electric vehicles due to their high specific energy density. However, a major challenge with Li–CO2 batteries is to attain reversible formation and decomposition of the Li2CO3 and carbon discharge products. A fully reversible Li–CO2 battery is developed with overall carbon neutrality using MoS2 nanoflakes as a cathode catalyst combined with an ionic liquid/dimethyl sulfoxide electrolyte. This combination of materials produces a multicomponent composite (Li2CO3/C) product. The battery shows a superior long cycle life of 500 for a fixed 500 mAh g?1 capacity per cycle, far exceeding the best cycling stability reported in Li–CO2 batteries. The long cycle life demonstrates that chemical transformations, making and breaking covalent C? O bonds can be used in energy‐storage systems. Theoretical calculations are used to deduce a mechanism for the reversible discharge/charge processes and explain how the carbon interface with Li2CO3 provides the electronic conduction needed for the oxidation of Li2CO3 and carbon to generate the CO2 on charge. This achievement paves the way for the use of CO2 in advanced energy‐storage systems. 相似文献