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排序方式: 共有198条查询结果,搜索用时 31 毫秒
51.
Angelina Pena Sofia Duarte Andr M. P. T. Pereira Liliana J. G. Silva Clia S. M. Laranjeiro Marta Oliveira Celeste Lino Simone Morais 《Molecules (Basel, Switzerland)》2022,27(1)
Human biomonitoring (HBM) data provide information on total exposure regardless of the route and sources of exposure. HBM studies have been applied to quantify human exposure to contaminants and environmental/occupational pollutants by means of determining the parent compounds, their metabolites, or even their reaction products in biological matrices. HBM studies performed among the Portuguese population are dispersed and limited. Thus, to overcome this knowledge gap, this work reviews the published Portuguese HBM information concerning mycotoxins detected in the urine, serum, milk, hair, and nails of different groups of the Portuguese population. This integrative approach to the available HBM data allows us to analyze the main determinants and patterns of exposure of the Portuguese population to the selected hazardous compounds, as well as to assess the potential health risks. We also aimed to identify the main difficulties and challenges of HBM through the analysis of the enrolled studies. Ultimately, this study aims to support national and European policies in promoting human health by summarizing the most important outcomes and lessons learned through the HBM studies carried out in Portugal. 相似文献
52.
Angelina Pena Sofia Duarte Andr M. P. T. Pereira Liliana J. G. Silva Clia S. M. Laranjeiro Marta Oliveira Celeste Lino Simone Morais 《Molecules (Basel, Switzerland)》2022,27(1)
Human biomonitoring (HBM) data provide information on total exposure regardless of the route and sources of exposure. HBM studies have been applied to quantify human exposure to contaminants and environmental/occupational pollutants by determining the parent compounds, their metabolites or even their reaction products in biological matrices. HBM studies performed among the Portuguese population are disperse and limited. To overcome this knowledge gap, this review gathers, for the first time, the published Portuguese HBM information concerning polycyclic aromatic hydrocarbons (PAHs), metals, metalloids, and pesticides concentrations detected in the urine, serum, milk, hair, and nails of different groups of the Portuguese population. This integrative insight of available HBM data allows the analysis of the main determinants and patterns of exposure of the Portuguese population to these selected hazardous compounds, as well as assessment of the potential health risks. Identification of the main difficulties and challenges of HBM through analysis of the enrolled studies was also an aim. Ultimately, this study aimed to support national and European policies promoting human health and summarizes the most important outcomes and lessons learned through the HBM studies carried out in Portugal. 相似文献
53.
54.
Francesco Ciardelli Angelina Altomare Simona Bronco Lotfi Oulderrahmania Francesco Masi 《Macromolecular Symposia》2000,156(1):147-154
After a short comparative analysis of different macromolecular ligands reported in the relevant literature, the presentation will be centered on the results obtained in the authors' laboratory using structurally defined inorganic supports in terms also of their macromolecular structure. Zeolites and mesomorphous silica can link, after proper chemical modification of their surface with MAO, unmodified metallocene complexes through cage entrapment and weak interactions, thus allowing the transfer from the solution to the solid phase. The metallocene complexes in their new phase are characterized by the catalytic behavior in olefin polymerization after activation with MAO. A decrease of productivity is generally observed depending on the type of support. The steric hindrance provided by the support is evidenced by the depression of chain transfer rate with formation of higher molecular weight polymers. Also shape selectivity is observed during copolymerization of ethylene with α‐olefins having variable size. These steric effects are released when going from HY zeolite to MCM silica. 相似文献
55.
56.
Angelina M Stoyanova 《Analytical sciences》2008,24(5):595-599
The analytical features of the reaction between N-phenylanthranilic acid (PAA) and potassium periodate in acidic medium are explored with the aim of improving the catalytic kinetic determination of iron in water samples. In the presence of Fe(II, III), PAA is oxidized by potassium periodate in a formic acid medium to form a violet-colored compound. The reaction is followed spectrophotometrically by measuring the increase in the absorbance of the oxidation product at 525 nm. The variables that affected the reaction rate were investigated and the reaction conditions were established. Calibration graphs are linear in the range of concentrations 2 - 500 ng mL(-1). As low as 10(-8) mol L(-1) Fe(II, III) can be easily determined by the fixed time method. The established catalytic method was successfully applied to the determination of iron in tap water and in pharmaceutical samples. 相似文献
57.
Angelina V. Biitseva Olha V. Hordiyenko Volodymyr A. Sukach Myhailo V. Vovk Konstantin A. Pichugin Irina S. Konovalova Oleg V. Shishkin 《Monatshefte für Chemie / Chemical Monthly》2008,139(8):939-943
The condensation of binucleophilic 3-amino-1-arylimino-1H-isoindoles with bifunctional 1-chloro-benzylisocyanates occurs regioselectively resulting in 3,4-dihydro-1,3,5-triazino[2,1-a]isoindol-2-one derivatives. The structures of the synthesized compounds were unambiguously established by NOE experiments.
Correspondence: Olha V. Hordiyenko, Chemistry Department, Kyiv National Taras Shevchenko University, 01033 Kyiv, Ukraine. 相似文献
58.
Zlata tefanac und Angelina Verbi 《Fresenius' Journal of Analytical Chemistry》1967,232(2):113-115
Ohne Zusammenfassung 相似文献
59.
Anna Maria Lapi Angelina Altomare Michele Alderighi Andrea Corti Alberto Dessy Federica Chiellini Antonella Solimando Roberto Solaro 《Journal of polymer science. Part A, Polymer chemistry》2013,51(18):3800-3809
Multiblock copolymers containing periodically spaced side‐chain carboxyl groups were obtained by a two‐step synthesis involving the preparation of ABA triblock prepolymers of ε‐caprolactone (A blocks) and ethylene glycol (B block) followed by chain extension to ABAn multiblock copolymers by reaction with pyromellitic dianhydride (PMDA). NMR analysis demonstrated the incorporation of PMDA in polymer chain and revealed the possibility of PMDA units to exist in two isomers, cisoid and transoid forms. Chain extension resulted in the incorporation of free carboxylic groups in polymer backbone and in an almost twofold increase of molecular weight. Thermal analysis indicated that the presence of PMDA residues interferes with the formation of crystalline phases by the chain‐extended polymers. The polymers were found to slowly degrade in buffer solution at 37 °C. Further, the carboxylated polymers can be processed into nanoparticulates by nanoprecipitation. Depending on the selected organic solvent, the particulate was constituted by either a monodispersed nanoparticles with average size of 150 nm or a bimodal distribution centered at about 100 nm and 7 μm. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3800–3809 相似文献
60.
Graham Kendall Ruibin Bai Jacek Błazewicz Patrick De Causmaecker Michel Gendreau Robert John Jiawei Li Barry McCollum Erwin Pesch Rong Qu Nasser Sabar Greet Vanden Berghe Angelina Yee 《The Journal of the Operational Research Society》2016,67(4):676-689
Good Laboratory Practice has been a part of non-clinical research for over 40 years. Optimization Research, despite having many papers discussing standards being published over the same period of time, has yet to embrace standards that underpin its research. In this paper we argue the need to adopt standards in optimization research. Building on previous papers, many of which have suggested that the optimization research community should adopt certain standards, we suggest a concrete set of recommendations that the community should adopt. We also discuss how the proposals in this paper could be progressed. 相似文献