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The synergic extraction of uranyl thiocyanate with binary system of 1-phenyl-3-methy1~4-benzoylpyrazolone-5 (PMBP)and tributyl phosphate(TBP)or tetraphenylarsonium chloride [(C6H5)4AsCl] and ternary system of PMBP-TBP-(C6H5 )4AsCl was studied.There was an obvious synergic effect of uranium (VI)from thiocyanate medium in binary and ternary systems.The formation of a ternary extracted complex,(C6H5)4AsUO2.(NCS)A2 TBP,was confirmed by the slope method.A method was first proposed for the calculation of the equilibrium constant of ternary synergic reaction. 相似文献
123.
An ion chromatographic method is described for the purpose of quality control in the process of monochloroacetic acid production. Using 2.5 mM NaOH–10% methanol as eluent, the simultaneous determination of acetic acid, monochloroacetic acid, dichloroacetic acid, and Cl− was obtained in a single run. Monochloroacetic acid and dichloroacetic acid showed good linearity in the range 0.1–20 and 0.15–20 μg/ml and correlation coefficients were 0.9999 and 0.9998, respectively. The detection limits (signal-to-noise ratio 3:1) of monochloroacetic acid and dichloroacetic acid were 17 and 25 ng/ml. This simple, sensitive, and time-saving method can be applied for composition analysis in acetic acid chlorination production. 相似文献
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Gabriele Sciacca Petra Martini Sara Cisternino Liliana Mou Jonathan Amico Juan Esposito Giancarlo Gorgoni Emiliano Cazzola 《Molecules (Basel, Switzerland)》2021,26(20)
Cyclotron-based radionuclides production by using solid targets has become important in the last years due to the growing demand of radiometals, e.g., 68Ga, 89Zr, 43/47Sc, and 52/54Mn. This shifted the focus on solid target management, where the first fundamental step of the radiochemical processing is the target dissolution. Currently, this step is generally performed with commercial or home-made modules separated from the following purification/radiolabelling modules. The aim of this work is the realization of a flexible solid target dissolution system to be easily installed on commercial cassette-based synthesis modules. This would offer a complete target processing and radiopharmaceutical synthesis performable in a single module continuously. The presented solid target dissolution system concept relies on an open-bottomed vial positioned upon a target coin. In particular, the idea is to use the movement mechanism of a syringe pump to position the vial up and down on the target, and to exploit the heater/cooler reactor of the module as a target holder. All the steps can be remotely controlled and are incorporated in the cassette manifold together with the purification and radiolabelling steps. The performance of the device was tested by processing three different irradiated targets under different dissolution conditions. 相似文献
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Eutectic molecular liquids (EMLs) based on hydrogen‐bonding interaction and π–π stacking were prepared. We found that the thermodynamic properties like initial decomposition temperature and glass transition temperature of EMLs are mainly dominated by the hydrogen bond donor, which is beneficial for designing and preparing new EMLs. These new liquid systems could be applied in the field of environmental and material science. 相似文献
129.
Ming Luo Yuzhou Jiang Jingbei Su Zhuoyi Deng Fangzhi Mou Leilei Xu Jianguo Guan 《化学:亚洲杂志》2019,14(14):2503-2511
Extraction of nucleic acids in microsystems is of significance for biomedical applications, but the current extraction methods generally require sophisticated microchannels and external equipment, hindering their practical applications. In this work, we have demonstrated a simple, versatile and efficient approach to extract nucleic acids in microsystems by developing cationic branched polyethyleneimine (PEI)‐functionalized tubular micromotors. The as‐developed tubular micromotors are fabricated by a two‐step process combining the template‐assisted electrodeposition and carbodiimide chemistry, and contain an inner catalytic Pt layer, a middle magnetic Ni layer and an outer cationic PEI layer. They exhibit autonomous bubble‐propelled motion in aqueous hydrogen peroxide solutions, which can be guided by an external magnetic field, and the surface charges can be reversibly modulated by changing the pH value of the solution. Consequently, the as‐developed tubular micromotors can selectively absorb nucleic acids from acidic solutions and desorb them into alkaline solutions, leading to the extraction of nucleic acids with high efficiency without external stirring. Furthermore, they can be operated in a microchannel chip without the aid of a pumping system. Our results indicate that this PEI‐functionalized tubular micromotor platform provides a novel, simple and versatile microsystem nucleic acid extraction technology, holding considerable promise for important practical applications. 相似文献