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101.
可生物降解聚酯酰胺共聚物的合成与表征 总被引:8,自引:0,他引:8
以两种合成的酰胺二元醇和癸二酸为原料合成了可生物降解的聚酯酰胺共聚物,研究了该癸半晶性聚合物的合成、结晶及其生物降解性,并应用IR,^1H NMR,SEM及DSC进行了表征。 相似文献
102.
103.
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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105.
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
106.
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
107.
108.
限进介质固相萃取及其应用 总被引:5,自引:0,他引:5
系统地介绍了限进介质固相萃取的原理、特点、发展现状及其发展趋势,并对该技术在生物和环境样品前处理中的应用作了较详细的综述。引用文献58篇。 相似文献
109.
An modified laminar crystal sodium silicate(Al-SKS-6)was synthesized by spray drying and high temperature crystallization using sodium silicate as silicon source,Al atom as inorganic source and hexadecyltrimethy ammomum bromide(CTMAB)as the structure template.The hydrothermal stability of product was at least 1 h.The synthesized material was characterized by XRD and SEM.The results indicated that shape and intensity of XRD diffraction peak at 20 took changes.but raw material δ phase crystal form kept unchanged.and assured high Ca2+ and Mg2+ binding capacity of the products.The Ca2+ and Mg2+ binding capacity of product is up to 380 mg Ca/g and 410mg Mg/g respectively.It was found that the hole of product became smaller and appeared rod structure based on SEM. The hydrothermal stability was increased due to the pillaring of A1 atom. 相似文献
110.
Chein‐I Wu Jiann‐Wen Huang Ya‐Lan Wen Shaw‐Bing Wen Yun‐Hwei Shen Mou‐Yung Yeh 《中国化学会会志》2009,56(6):1231-1235
Stable aqueous dispersions of silver (Ag) nanoparticles were prepared by reducing silver nitrate solutions with sodium borohydride (NaBH4) in the presence of waterborne polyurethane as a stabilizing agent. WPU/Ag nanocomposites were obtained after evaporating water. Transmission electron microscope (TEM) shows nanoscale Ag particles are well dispersed in WPU matrix at a lower concentration, while particles exhibit a little aggregation at a higher concentration. UV‐visible spectra, X‐ray powder diffraction, and energy dispersive X‐ray spectrometer (EDS) confirm the existence of Ag particle in WPU matrix. The WPU/Ag composite films show good antibiotic ability. 相似文献