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Journal of Radioanalytical and Nuclear Chemistry - Proficiency testing is an important way of evaluating the analytical method used in the laboratory. In recent years, neutron activation analysis...  相似文献   
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Three novel dental monomers containing phosphonic acid groups ( 1a and 2a , based on diethyl amino(phenyl)methylphosphonate and 3a based on diethyl 1‐aminoheptylphosphonate) were synthesized in two steps: the reaction of α‐aminophosphonates with acryloyl chloride (for monomers 1a and 3a ) or methacryloyl chloride (for 2a ) to give monomers with phosphonate groups, and the hydrolysis of phosphonate groups by using trimethyl silylbromide. Their (and the intermediates') structures were confirmed by FTIR, 1H, 13C, and 31P NMR spectroscopy. All the monomers dissolve well in water (1<pH<2) and are hydrolytically stable. Their homo‐ and copolymerizations with 2‐hydroxyethyl methacrylate (HEMA) and HEMA/glycerol dimethacrylate were investigated with photo‐DSC. Thermal polymerization of the new monomers in water or in ethanol/water solution was investigated, giving polymers in good yields. X‐ray diffraction results showed only dicalcium phosphate dehydrate formation upon interaction of 1a ‐ 3a with hydroxyapatite indicating its strong decalcification and that monomer‐Ca salts are highly soluble. Some results were also compared to those with a bisphosphonic acid‐containing methacrylamide ( 4a ) previously reported; and the influence of monomer structure on polymerization/adhesive properties is discussed. These properties, especially hydrolytic stability and good rates of polymerization, make these new monomers suitable candidates as components of dental adhesive mixtures. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 511–522  相似文献   
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In the present work, the transport of Zn(II) metal ion from an aqueous nitrate solution of different metal ions through a polymer inclusion membrane (PIM) containing calix[4]resorcinarene derivative used as a carrier were investigated. Zn(II)metal ion showing high permeability were transported through PIMs prepared from cellulose triacetate (CTA) as a polymeric support material and 2-NPOE as a plasticizer. Total Zn(II) concentration was determined with an Atomic Absorption Spectrometer (AAS) in the acceptor phase. The prepared PIM and supported liquid membrane (SLM) were characterized by using Scanning Electron Microscopy(SEM) and Atomic Force Microscopy (AFM) techniques. The effects of membrane composition, effects of type of plasticizer in the membrane, effects of carrier concentration, and the thickness of the membranes were examined in the facilitated transport experiments of Zn(II) ion through PIM. We compared the performance of SLM experiments under the optimum conditions identified by the PIM studies. Higher permeability coefficient values for Zn(II) was found for SLM, while lower values were ascertained for PIM. The kinetic parameters which have been calculated as the constant rate (k), permeability coefficient (P), flux (J) and diffusion coefficient (D).  相似文献   
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A new and convenient synthesis for amino‐phthalimide (1H‐isoindole‐1,3(2H)‐dione) derivatives has been developed starting from an α,β‐unsaturated ketone. The ketones were reacted with amines to give aromatic amine products. This is the first time that substituted amine groups have been incorporated in aromatic rings. The mechanism of the product formation is rationalized by the 1,2‐addition of amines to ketones. All aromatic compounds exhibited high fluorescence properties at the blue‐green region.  相似文献   
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Pesticide use in agriculture is one of the threats to water safety. Therefore, detection of pesticide residues is crucial for human health. Compared to conventional chromatographic methods, aptasensors are promising tools for fast, cheap and sensitive detection of environmental contaminants. To the best of our knowledge, such an aptasensor has not been reported for imidacloprid (Imi) which is one of the most widely used pesticides. In order to meet this demand, we initially selected two novel aptamers designated as ‘Apta‐1’ and ‘Apta‐2’ by graphene oxide‐SELEX (GO‐SELEX) method. Then, these aptamers were used to fabricate the gold electrode‐based aptasensor platforms and characterized by using electrochemical methods such as cyclic voltammetry, and electrochemical impedance spectroscopy as well as X‐Ray photoelectron spectroscopy. It was found that the limit of detection value of Apta‐1 based sensor for the Imi was found better than Apta‐2 based system, although linear ranges were similar. Based on that finding, Apta‐1 based system was further tested against possible interference molecules. The proposed platform was successfully used for detection of very low concentrations of Imi in the range of ng/mL. Thus, it eliminates the need for sample pre‐treatment and enables a practical analysis in real wastewater samples.  相似文献   
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Disulfiram (DS), known as an anti-alcoholism drug, has shown a potent antiviral activity. Still, the potential clinical application of DS is limited by its low water solubility and rapid metabolism. Cyclodextrins (CDs) have been widely used to improve the solubility of drugs in water. In this study, five concentrations of hydroxypropyl β-cyclodextrin (HP) and sulfobutyl ether β-cyclodextrin (SBE) were used to form inclusion complexes of DS for enhanced solubility. Solutions were freeze-dried, and the interaction between DS and CD was characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). In addition, the nebulization properties of the DS–CD solutions were studied. The aqueous solubility of DS increased significantly when loaded to either of both CDs. The phase solubility of both complexes was a linear function of the CD concentration (AL type). Furthermore, physicochemical characterization studies showed a potent inclusion of the drug in the CD–DS complexes. Aerosolization studies demonstrated that these formulations are suitable for inhalation. Overall, the CD inclusion complexes have great potential for the enhancement of DS solubility. However, further studies are needed to assess the efficacy of DS–CD inclusion complexes against SARS-CoV-2 via nebulization.  相似文献   
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The generation of conditional alleles using CRISPR technology is still challenging. Here, we introduce a Short Conditional intrON (SCON, 189 bp) that enables the rapid generation of conditional alleles via one-step zygote injection. In this study, a total of 13 SCON mouse lines were successfully generated by 2 different laboratories. SCON has conditional intronic functions in various vertebrate species, and its target insertion is as simple as CRISPR/Cas9-mediated gene tagging.Subject terms: Genetic engineering, Gene targeting, Genetic models  相似文献   
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