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181.
Journal of Analytical Chemistry - An Erratum to this paper has been published: https://doi.org/10.1134/S1061934822340019  相似文献   
182.
Journal of Cluster Science - The aim of present study was to develop and evaluate novel in situ nanoemulgel (NEG) of azithromycin (AZM) with eugenol for intra-pocket drug delivery for the treatment...  相似文献   
183.
A very simple and selective spectrophotometric method for simultaneous determination of iron(II), nickel(II) and cobalt(II) based on formation of their complexes with 1-(2-pyridylazo)-2-naphtol (PAN) in micellar media is described. Although the complexes of Fe(II), Ni(II) and Co(II) with reagent show a spectral overlap, they have been simultaneously determined by partial least squares (PLS) with and without preprocessing step using direct orthogonal signal correction (DOSC). The linear range was 0.30-4.50 μg ml−1 for Co(II), 0.20-3.00 μg ml−1 for Ni(II) and 0.30-5.00 μg ml−1 for Fe(II). The results obtained by the PLS and DOSC-PLS were statistically compared. Interference effects of common anions and cations were studied and the proposed method was also applied satisfactorily to the determination of Fe(II), Ni(II) and Co(II) in synthetic samples.  相似文献   
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A straightforward and atom-economical base-free palladium-catalyzed regioselective direct arylation of coumarins and chromenones is devised. This protocol is compatible with a wide variety of electron-donating and -withdrawing substituents and allows construction of various biologically important flavone and neoflavone backbones.  相似文献   
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An efficient and straightforward procedure for the Suzuki–Miyaura cross-coupling reaction was studied by using aryldiazonium silica sulfates and sodium tetraphenylborate in the presence of a catalytic amount of Pd(OAc)2. These reactions were carried out in water at room temperature without using additional ligands.  相似文献   
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To assess coastal ecosystem status and pollution baselines, prawns were collected from the commercial catches of eight Asia-Pacific countries (Australia, Bangladesh, Indonesia, Myanmar, Philippines, Pakistan, Sri Lanka and Thailand). Samples collected from 21 sites along regional coastlines were analysed for trace metal and stable isotopic compositions of H, C, N, O and S. A combination of simple averaging and multivariate analyses was used to evaluate the data. Sites could be assigned to easily recognise polluted and unpolluted groups based on the prawn results. Some filter-feeding clams were also collected and analysed together with the benthic-feeding prawns, and the prawns generally had lower trace metal burdens. Climate change effects were not strongly evident at this time, but altered ocean circulation and watershed run-off patterns accompanying future climate change are expected to change chemical patterns recorded by prawns along these and other coastlines. Stable isotopes, especially 15N, can help to distinguish between relatively polluted and unpolluted sites.  相似文献   
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