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Anh Ha Lan Nhan Dang Duc Frew Russell Quynh Tran Minh 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3613-3621
Journal of Radioanalytical and Nuclear Chemistry - This research aimed to authenticate the geographical origin of imported fresh apples using isotopic techniques. The results show that the... 相似文献
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Zeus A. De los Santos Sean MacAvaney Katina Russell Christian Wolf 《Angewandte Chemie (International ed. in English)》2020,59(6):2440-2448
We have developed an optical method for accurate concentration, er, and dr analysis of amino alcohols based on a simple mix‐and‐measure workflow that is fully adaptable to multiwell plate technology and microscale analysis. The conversion of the four aminoindanol stereoisomers with salicylaldehyde to the corresponding Schiff base allows analysis of the dr based on a change in the UV maximum at 420 nm that is very different for the homo‐ and heterochiral diastereomers and of the concentration of the sample using a hypsochromic shift of another absorption band around 340 nm that is independent of the analyte stereochemistry. Subsequent in situ formation of CuII assemblies in the absence and presence of base enables quantification of the er values for each diastereomeric pair by CD analysis. Applying a linear programming method and a parameter sweep algorithm, we determined the concentration and relative amounts of each of the four stereoisomers in 20 samples of vastly different stereoisomeric compositions with an averaged absolute percent error of 1.7 %. 相似文献
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Crosslinked poly(ethylene oxide) containing siloxanes fabricated through thiol‐ene photochemistry 下载免费PDF全文
Victor A. Kusuma Elliot A. Roth William P. Clafshenkel Steven S. Klara Xu Zhou Surendar R. Venna Erik Albenze David R. Luebke Meagan S. Mauter Richard R. Koepsel Alan J. Russell David Hopkinson Hunaid B. Nulwala 《Journal of polymer science. Part A, Polymer chemistry》2015,53(13):1548-1557
Homogenous amphiphilic crosslinked polymer films comprising of poly(ethylene oxide) and polysiloxane were synthesized utilizing thiol‐ene “ click ” photochemistry. A systematic variation in polymer composition was Carried out to obtain high quality films with varied amount of siloxane and poly(ethylene oxide). These films showed improved gas separation performance with high gas permeabilities with good CO2/N2 selectivity. Furthermore, the resulting films were also tested for its biocompatibility, as a carrier media which allow human adult mesenchymal stem cells to retain their capacity for osteoblastic differentiation after transplantation. The obtained crosslinked films were characterized using differential scanning calorimetry, dynamic mechanical analysis, thermogravimetric analysis, FTIR, Raman‐IR , and small angle X‐ray scattering. The synthesis ease and commercial availability of the starting materials suggests that these new crosslinked polymer networks could find applications in wide range of applications. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1548–1557 相似文献
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Dr. Lucy Clark Dr. Farida H. Aidoudi Dr. Cameron Black Dr. Kasun S. A. Arachchige Prof. Dr. Alexandra M. Z. Slawin Prof. Dr. Russell E. Morris Prof. Dr. Philip Lightfoot 《Angewandte Chemie (International ed. in English)》2015,54(51):15457-15461
The ionothermal synthesis, structure, and magnetic susceptibility of a novel inorganic–organic hybrid material, imidazolium vanadium(III,IV) oxyfluoride [C3H5N2][V9O6F24(H2O)2] (ImVOF) are presented. The structure consists of inorganic vanadium oxyfluoride slabs with kagome layers of V4+ S=${{ 1/2 }}$ ions separated by a mixed valence layer. These inorganic slabs are intercalated with imidazolium cations. Quinuclidinium (Q) and pyrazinium (Pyz) cations can also be incorporated into the hybrid structure type to give QVOF and PyzVOF analogues, respectively. The highly frustrated topology of the inorganic slabs, along with the quantum nature of the magnetism associated with V4+, means that these materials are excellent candidates to host exotic magnetic ground states, such as the highly sought quantum spin liquid. Magnetic susceptibility measurements of all samples suggest an absence of conventional long‐range magnetic order down to 2 K despite considerable antiferromagnetic exchange. 相似文献
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Dr. Samuel C. Scott Dr. Jamie A. Cadge Grace K. Boden Prof. John F. Bower Dr. Christopher A. Russell 《Angewandte Chemie (International ed. in English)》2023,62(23):e202301526
We describe a AuI complex of a hemi-labile (C^N) N-heterocyclic carbene ligand that is able to mediate oxidative addition of aryl iodides. Detailed computational and experimental investigations have been undertaken to verify and rationalize the oxidative addition process. Application of this initiation mode has resulted in the first examples of “exogenous oxidant-free” AuI/AuIII catalyzed 1,2-oxyarylations of ethylene and propylene. These demanding yet powerful processes establish these commodity chemicals as nucleophilic-electrophilic building blocks in catalytic reaction design. 相似文献
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In situ and operando techniques providing information regarding adsorbate bonding and atomic arrangements on the electrode surface along with pure electrochemical measurements are needed to more fully understand the detailed mechanism of electrocatalytic reactions on high surface areas/nanoparticle electrocatalysts. X-ray adsorption spectroscopy (XAS) is a powerful tool to interrogate the electronic structure and local coordination environment of such electrocatalysts under working conditions, but it should be acknowledged that standard XAS methods are not intrinsically surface sensitive. This review will present recent in situ XAS studies on single-atom, metal, and metal oxide electrocatalysts, highlighting the approaches taken to achieve surface sensitivity by careful designing of the sample under investigation. 相似文献