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61.
Aleksandra Pawlaczyk Magdalena Gajek Martyna Balcerek Magorzata I. Szynkowska-J
wik 《Molecules (Basel, Switzerland)》2021,26(21)
Eye shadows, which are products willingly and frequently used by women and even children, have been reported in literature to contain toxic metals. In this work, a total of 94 eye shadows samples available on the Polish market were collected. Eye shadow products have been selected in order to include several parameters important from the point of view of the typical consumer such as: product type (mat/pearl), consumer group (for adults and children), price range (very cheap, medium price, expensive and very expensive), color (twelve different colors were tested), manufacturer (eight brands were investigated) or country of production (four countries were included). The concentration of selected metals (Ag, Ba, Bi, Cd, Pb, Sr, Tl) was determined by ICP-MS technique after the sample extraction with a mixture of nitric acid and hydrogen peroxide in a microwave closed system. For Ag, Cd and Tl, some results were below the established limit of quantification for the employed technique. The presence of strontium, barium, lead and bismuth was confirmed in all studied samples. The obtained results for analyzed elements were, in general, quite comparable with the data reported by other authors. A small number of samples exceeding the permissible values (two samples were beyond the limit value for Cd of 0.5 mg/kg and one exceed the acceptable concentration for Pb of 10 mg/kg) also proves a relatively good condition of the Polish cosmetics market and suggests insubstantial risk for the potential consumers. The results gathered for some of the eye shadows intended for children turned out to be alarmingly high, in particular for elements such as Cd. The highest concentration of Cd reached almost 4 mg/kg, while of Pb amounted to 16 mg/kg. The presence of the statistically significant differences was confirmed for all included parameters with an exception of the color of the eye shadow. Considering the results acquired only for Cd and Pb with respect to the country of origin, the least contaminated cosmetics by metallic impurities seem to be the one produced in Canada, while the ones presenting the highest health risk among all studied eye shadows are make-up cosmetics originating from Poland and Italy. Multivariate analysis of a large data set using CA methods and PCA provided valuable information on dependencies between variables and objects. 相似文献
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Joanna Kowalczuk Andrzej apiski Elbieta Stolarczyk Oleg M. Demchuk Konrad Kubiski Monika Janeczko Aleksandra Martyna Maciej Masyk Sylwia Turczyniak-Surdacka 《Molecules (Basel, Switzerland)》2021,26(24)
An aqueous solution of sodium citrate stabilized gold nanoparticles (AuNP) in the presence of N-lauroyl-L-alanine (C12ALA) forms a stable gel. The structure of the gel and the distribution profile of AuNP in it were analyzed. Will nanoparticles separated from each other with sodium citrate behave in the same way in solution and trapped in the gel matrix? Will the spatial limitation of solvent molecules aggregate nanoparticles and destroy their homogeneity? These questions are very important from the point of view of the use of gold nanoparticles, trapped in the gel structure as carriers of drugs in the slow-release process. The lack of homogeneity of this distribution will have a major impact on the rate of release of the appropriate amount of therapeutic drug from the matrix. In this work, we attempt to answer these questions. The performed biological assays revealed that both C12ALA and C12ALA-AuNP show an excellent level of biological neutrality. They might be used as a transporting medium for a drug delivery without affecting the drug’s activity. 相似文献
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Martyna Durko-Maciag Prof. Denis Jacquemin Dr. Gilles Ulrich Dr. Julien Massue Prof. Jaroslaw Mysliwiec 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(44):e202201327
The excited-state intramolecular proton transfer chromophores were regarded as good materials for laser action generation due to their inherent four-level photocycle. The excitation-dependent properties of these compounds enable light amplification from two distinct forms: both enol and keto, making it possible to obtain dual fluorescence emission. Herein, we report that a third option is possible for the first time stimulated emission was realized with a deprotonated ESIPT molecule based on a novel rigidified 2-(2’-hydroxyphenyl)benzothiazole derivative, triggering the possibility to fabricate real-time tunable active material. Through the rational engineering of the ratio of each emissive species, a red-green-blue device was fabricated with the possibility of white light generation. The degenerated two-wave mixing setup was applied to construct a continuously tunable distributed feedback laser. 相似文献
66.
New Squaraine‐based two‐component initiation systems for UV‐blue light induced radical polymerization: Kinetic and time‐resolved laser spectroscopy studies 下载免费PDF全文
Janina Kabatc Katarzyna Kostrzewska Katarzyna Jurek Martyna Kozak Alicja Balcerak Łukasz Orzeł 《Journal of polymer science. Part A, Polymer chemistry》2017,55(3):471-484
In this article, the ability of two‐component photoinitiator systems for efficient polymerization of 2‐ethyl‐2‐(hydroxymethyl)?1,3‐propanediol triacrylate was presented. The photophysics and photochemistry of squaraine dyes in the presence of an electron donor as well as an electron acceptor was investigated, and it was found that the photosensitizer in an excited state might act as an electron acceptor or an electron donor. The excited states of squaraines may be quenched by tetramethylammonium n‐butyltriphenylborate ( B2 ), diphenyliodonium chloride ( I1 ), and N‐methoxy‐4‐phenylpyridinium tetrafluoroborate ( NO ). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 471–484 相似文献
67.
Marcelina Binczyk Martyna Nowak Monika Skrobanska Bartosz Tylkowski Tomasz Runka Renata Jastrzab 《Journal of the Iranian Chemical Society》2016,13(5):841-845
A silver Compact Disc Recortable (CD-R) based substrate has been proposed as an alternative to silver colloids as active material successfully used in surface-enhanced Raman spectroscopy (SERS). Scanning Electron Microscope (SEM) and Energy-Dispersive X-ray Spectroscopy (EDXS) measurements revealed that silver nanoparticles are present over the entire surface of the uncovered reflective layer of commonly used CD-R. The process of preparation of the CD-R based surface is simple, fast and repeatable. Recorded Raman spectra of 10 µM Rhodamine 6G applied to the substrate corroborate strong enhancement of Raman signal. The maximum value of EF was calculated to be about 5.76 × 106. Raman maps are consistent with SEM micrographs and confirmed the presence of a numerous SERS hot spots occurring on the trucks of CD-R based substrate. 相似文献
68.
Bożena Modzelewska-Banachiewicz Barbara Michalec Teresa Kamińska Liliana Mazur Anna E. Kozioł Jacek Banachiewicz Marzena Ucherek Martyna Kandefer-Szerszeń 《Monatshefte für Chemie / Chemical Monthly》2009,140(4):439-444
Abstract (Z)-3-(3,4-diaryl-1,2,4-triazole-5-yl)prop-2-enoic acid derivatives were obtained in the course of the reaction of N
3-substituted amidrazones with maleic anhydride, and isomerized into the (E) isomers by heating under reflux in acetic acid solution. The molecular structure of the compounds obtained was confirmed
by IR and 1H NMR spectroscopy, and by X-ray crystallography for (2E)-3-(4,5-diphenyl-4H-1,2,4-triazol-3-yl)prop-2-enoic acid. The antiviral and immunomodulating activity of several of the compounds was examined.
Graphical abstract
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69.
To gain further insight into liquid water's structure and explore the role of different physical forces underlying the interaction between water molecules, the radial and angular structure of water is probed as a function of temperature for a carefully selected set of theoretical models. Simulations are performed with empirical rigid, empirical polarizable, empirical flexible with classical and quantum nuclei, and ab initio models with classical nuclei at 300 and 353 K and quantum nuclei at 300 K. The predicted radial distribution functions, spatial maps, and angular distributions of the neighboring water molecules are consistent with a model of liquid water in which water molecules are tetrahedrally coordinated. In addition, three-dimensional joint distribution functions are introduced and analyzed. By comparison of the functions obtained for hexagonal ice to those of liquid water, several thermally disordered, ice-like cluster structures are identified in the fluid. 相似文献
70.
Marek Pekala Jan Grabski Martyna Jachimowicz 《Monatshefte für Chemie / Chemical Monthly》2002,12(8):815-822
Magnetic properties of nanocrystalline Fe78B13Si9 alloys are studied for three series prepared by ball milling starting from amorphous ribbons, crystallized ribbons, and elemental powders. Temperature variation of static magnetization results in strong ferromagnetic interaction which is weakly dependent on the initial material. Magnetic hysteresis loops show that saturation magnetization, magnetic remanence, and coercive field increase with frequency for both series of ribbon samples, whereas they decrease for alloys prepared from elemental powders. Power losses raise faster for the alloys prepared from elemental powders than for the two other alloys. 相似文献