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91.
92.
Multi-residue analytical methods using LC-tandem MS for the determination of pharmaceuticals in environmental and wastewater samples: a review 总被引:1,自引:0,他引:1
Multi-residue analytical methodologies are becoming the preferred and required tools against single group analysis, as they
provide wider knowledge about the occurrence of pharmaceuticals in the environment necessary for further study of their removal,
partition and ultimate fate. However, simultaneous analysis of compounds from different groups with quite different physico-chemical
characteristics requires a compromise in the selection of experimental conditions, which in some cases are not the best conditions
for all the analytes studied. In this article, an overview of analytical methodologies focusing on the simultaneous determination
of acidic, neutral and basic compounds belonging to different therapeutical classes is presented. The state-of-the-art of
LC-MS/MS for multi-class analysis is reviewed, highlighting the specific requirements for such analysis. 相似文献
93.
94.
Mira Bozzini Christophe Rabut Milvia Rossini 《Advances in Computational Mathematics》2018,44(4):1003-1040
The aim of the paper is to construct a multiresolution analysis of L2(IRd) based on generalized kernels which are fundamental solutions of differential operators of the form \(\boldsymbol {\prod }_{\ell =?1}^{m}(-{\Delta }+\kappa _{\ell }^{2}\,I)\). We study its properties and provide a set of pre-wavelets associated with it, as well as the filters which are indispensable to perform decomposition and reconstruction of a given signal, being very useful in applied problems thanks to the presence of the tension parameters κ?. 相似文献
95.
96.
Mansoor Ahmed Qazi Ümmühan Ocak Miraç Ocak Shahabuddin Memon Imam Bakhsh Solangi 《Journal of fluorescence》2013,23(3):575-590
A readily available chromionophore 5,11,17,23-tetra-tert-butyl-25,27-bis(hydrazidecarbonylmethoxy)-26,28-dihydroxycalix[4]arene (HCC4) was employed as a chromogenic sensing probe selective for Pb(II) and Cr2O7 2? ions among a series of various ions such as Li(I), Na(I), K(I), Rb(I), Ba(II), Sr(II), Al(III), Cd(II), Co(II), Cu(II), Hg(II), Ni(II), Pb(II) and Zn(II) as well as Cr2O7 2?, CH3CO2 ?, Br?, Cl?, F?, I?, ClO4 ? and NO3 ? that have been examined by UV-visible and fluorescence spectroscopic techniques. The HCC4 in DCM-MeCN system forms 2:1 (ligand-metal) complex with Pb(II). It also shows 2:1 stoichiometry with Cr2O7 2?. The complexation phenomenon has been confirmed by FTIR spectroscopy that favors the selective nature of HCC4 with Pb(II) and Cr2O7 2?. Thermal gravimetric analysis (TGA) also supports its utility in drastic conditions. 相似文献
97.
Alberto Castellón Serrano José Antonio Cuenca Mira Cándido Martín González 《代数通讯》2013,41(10):4699-4706
This work, jointly with [9], completes the structure theory and classification of the Jordan H *- triple systems. The problem of describing the Jordan H *-triple systems is reduced in [5] to that of describing the topologically simple ones. Ruling out the finite-dimensional case, we have that any of these H *-triples has an underlying triple system structure of quadratic type (and these can be fully described), or it is the H *-triple system associated to the odd part of a topologically simple Z2-graded Jordan H *-algebra, whose classification is given in [13]. 相似文献
98.
Let W → 𝔸 2 be the universal Weierstrass family of cubic curves over ?. For each N ≥ 2, we construct surfaces parameterizing the three standard kinds of level N structures on the smooth fibers of W. We then complete these surfaces to finite covers of 𝔸 2. Since W → 𝔸 2 is the versal deformation space of a cusp singularity, these surfaces convey information about the level structure on any family of curves of genus g degenerating to a cuspidal curve. Our goal in this note is to determine for which values of N these surfaces are smooth over (0, 0). From a topological perspective, the results determine the homeomorphism type of certain branched covers of S 3 with monodromy in SL2 (?/N). 相似文献
99.
100.
Dr. Yujia Qing Mira D. Liu Denis Hartmann Dr. Linna Zhou Dr. William J. Ramsay Prof. Hagan Bayley 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(36):15841-15846
We report a single-molecule mechanistic investigation into 2-cyanobenzothiazole (CBT) chemistry within a protein nanoreactor. When simple thiols reacted reversibly with CBT, the thioimidate monoadduct was approximately 80-fold longer-lived than the tetrahedral bisadduct, with important implications for the design of molecular walkers. Irreversible condensation between CBT derivatives and N-terminal cysteine residues has been established as a biocompatible reaction for site-selective biomolecular labeling and imaging. During the reaction between CBT and aminothiols, we resolved two transient intermediates, the thioimidate and the cyclic precursor of the thiazoline product, and determined the rate constants associated with the stepwise condensation, thereby providing critical information for a variety of applications, including the covalent inhibition of protein targets and dynamic combinatorial chemistry. 相似文献