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101.
Ewelina Klem-Marciniak Marta Huculak-Mczka Kinga Marecka Krystyna Hoffmann Jzef Hoffmann 《Molecules (Basel, Switzerland)》2021,26(7)
In application conditions, the influence of environmental parameters on used fertilizer chelates and their distribution over time is important. For this purpose, the changes in the content of micronutrient ions and Fe-EDDHA and Fe-EDDHSA chelates in an aqueous medium at different pH values were studied. In the assumed time, changes in the ions content were analyzed using the voltammetry method at pH 3, 5 and 7. The content of isomers and chelate forms was analyzed by ion pair chromatography at pH 3, 5 and 7. These studies allowed us to determine the effect of pH on the stability of iron chelates over time. 相似文献
102.
Roszak Kinga Katrusiak Andrzej Dega-Szafran Zofia Komasa Anna Kowalczyk Iwona Szafran Mirosław 《Structural chemistry》2017,28(3):859-865
Structural Chemistry - The cation of 3-(trimethylammonium)-benzoic acid exhibits a considerable conformational flexibility connected to the orientation of carboxyl group, coupled to the proton... 相似文献
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105.
Kinga I. Leszczyska Volker Huch Carsten Prsang Jan Schwabedissen Raphael J. F. Berger David Scheschkewitz 《Angewandte Chemie (International ed. in English)》2019,58(15):5124-5128
Small‐ to medium‐sized clusters occur in various areas of chemistry, for example, as active species of heterogeneous catalysis or as transient intermediates during chemical vapor deposition. The manipulation of stable representatives is mostly limited to the stabilizing ligand periphery, virtually excluding the systematic variation of the property‐determining cluster scaffold. We now report the deliberate expansion of a stable unsaturated silicon cluster from six to seven and finally eight vertices. The consecutive application of lithium/naphthalene as the reducing agent and decamethylsilicocene as the electrophilic source of silicon results in the expansion of the core by precisely one atom with the potential of infinite repetition. 相似文献
106.
Drzewiecka Aleksandra Koziol Anna E. Pena Ruiz Tomas Fernandez Gomez Manuel Struga Marta Kossakowski Jerzy Ostrowska Kinga Lis Tadeusz 《Structural chemistry》2012,23(5):1617-1629
Structural Chemistry - The selected derivatives of the 2- and 3-benzo[b]furancarboxylic acids were synthesized and their structures were studied using the X-ray crystallography and the... 相似文献
107.
Assoc. Prof. Dr. Cem B. Yildiz Dr. Kinga I. Leszczyńska Dr. Sandra González-Gallardo Dr. Michael Zimmer Prof. Dr. Akin Azizoglu Priv.-Doz. Dr. Till Biskup Prof. Dr. Christopher W. M. Kay Dr. Volker Huch Prof. Dr. Henry S. Rzepa Prof. Dr. David Scheschkewitz 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(35):15199-15204
108.
Małgorzata Różanowska Kinga Handzel Michael E. Boulton Bartosz Różanowski 《Photochemistry and photobiology》2012,88(6):1362-1372
All‐trans‐retinal (AtRal) can accumulate in the retina as a result of excessive exposure to light. The purpose of this study was to compare cytotoxicity of AtRal and photodegraded AtRal (dAtRal) on cultured human retinal pigment epithelial cells in dark and upon exposure to visible light. AtRal was degraded by exposure to visible light. Cytotoxicity was monitored by imaging of cell morphology, propidium iodide staining of cells with permeable plasma membrane and measurements of reductive activity of cells. Generation of singlet oxygen photosensitized by AtRal and dAtRal was monitored by time‐resolved measurements of characteristic singlet oxygen phosphorescence. Photodegradation of AtRal resulted in a decrease in absorption of visible light and accumulation of the degradation products with absorption maximum at ~330 nm. Toxicity of dAtRal was concentration‐dependent and was greater during irradiation with visible light than in dark. DAtRal was more cytotoxic than AtRal both in dark and during exposure to visible light. Photochemical properties of dAtRal indicate that it may be responsible for the maximum in the action spectra of retinal photodamage recorded in animals. In conclusion, photodegradation products of AtRal may impose a significant threat to the retina and therefore their roles in retinal pathology need to be explored. 相似文献
109.
The structure of griseofulvic acid, C16H15ClO6, at 100 K has orthorhombic (P2(1)2(1)2) symmetry. It is of interest with respect to biological activity. The structure displays intermolecular O-H...O, C-H...O hydrogen bonding as well as week C-H...pi and pi...pi interactions. In strong acidic conditions the griseofulvin undergoes dimerization. The structure of dimerized griseofulvin, C34H32C12O12 x C2H6O x H2O, at 100 K has monoclinic (P2(1)) symmetry. The molecule crystallized as a solvate with one ethanol and one water molecule. The dimeric molecules form intermolecular O-H...O hydrogen bonds to solvents molecules only but they interact via week C-H...O, C-H...pi, C-Cl...pi and pi...pi interactions with other dimerized molecules. 相似文献
110.
Lazar A Danylyuk O Suwinska K Perret F Coleman AW 《Chemical communications (Cambridge, England)》2006,(8):903-905
An extremely complex solid state structure described by two virtual channels and a 2-D square grid of hydrogen bonds is generated by four carboxylic acids groups of calix[4]arene tetrabutyroxycarboxylic acid. 相似文献