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Mihails Arhangelskis Dejan-Kreimir Bu
ar Simone Bordignon Michele R. Chierotti Samuel A. Stratford Dario Voinovich William Jones Dritan Hasa 《Chemical science》2021,12(9):3264
We demonstrate that liquid additives can exert inhibitive or prohibitive effects on the mechanochemical formation of multi-component molecular crystals, and report that certain additives unexpectedly prompt the dismantling of such solids into physical mixtures of their constituents. Computational methods were employed in an attempt to identify possible reasons for these previously unrecognised effects of liquid additives on mechanochemical transformations.Liquid additives can exert catalytic, inhibitive or prohibitive effects on the mechanochemical formation of multi-component molecular crystals. 相似文献
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By use of the pyroelectric temperature analysis (PTA) of the unsintered pressed powder samples in the temperature region of the phase transition it is possible to determine the value of the electric charge released during the transition. The comparison of results of the transition charges obtained from unpoled as well as from poled samples can differentiate a ferroelectric from nonferroelectric material. The proposed method is successfully validated with KH2PO4, (NH4)2SO4 and NH4H2PO4 pressed powder. 相似文献
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Righi M Topi F Bartolucci S Bedini A Piersanti G Spadoni G 《The Journal of organic chemistry》2012,77(14):6351-6357
An efficient, one-pot reductive alkylation of indoles with N-protected aminoethyl acetals in the presence of TES/TFA is reported. It represents the first general method for the direct synthesis of tryptamine derivatives from indoles and nitrogen-functionalized acetals. This convergent and versatile approach employs safe and inexpensive reagents, proceeds under mild conditions, and tolerates several functional groups. The new procedure was efficiently applied to a gram-scale synthesis of both luzindole, a reference MT2-selective melatonin receptor antagonist, and melatonin. 相似文献
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Hočevar Mateja Berginc Marko Topič Marko Krašovec Urša Opara 《Journal of Sol-Gel Science and Technology》2010,53(3):647-654
A titanium oxide layer used in a dye-sensitized solar cell (DSSC) has to meet two opponent properties to enable high conversion
efficiency: a large surface area (for high dye loading) and good connection between TiO2 grains (for efficient extraction of electrons toward the front contact). In order to meet a trade-off between these criteria
a preparation method for TiO2 paste formulation based on Pechini sol–gel method and commercial nanocrystalline TiO2 powder has been developed. A series of TiO2 pastes with different molar ratios between titanium isopropoxide, citric acid and ethylene glycol (1:X:4X) in the paste have been examined. The structure and morphology as well as cross-cut tests of deposited and sintered TiO2 layers have been analyzed. Results reveal that the paste with X = 8 exhibits the best properties, resulting in an overall conversion efficiency of DSSC under standard test conditions (100 mW/cm2, 25 °C, AM 1.5G) up to 6.6% for ionic liquid based electrolyte. 相似文献
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Identification of differentially expressed, tumor-associated proteins in oral squamous cell carcinoma by proteomic analysis 总被引:6,自引:0,他引:6
Oral squamous cellular carcinoma is a malignant tumor with poor prognosis and therefore the discovery of early markers to discriminate malignant from normal cells would be of critical importance in clinical diagnosis. Subcellular fractions from oral squamous cell carcinoma (OSCC) and control samples, enriched in mitochondrial and cytosolic proteins, were analyzed by 2-DE, followed by MALDI-TOF-MS. Twenty proteins showed altered expression levels in OSCC; 14 were up- and 6 were down-regulated in comparison with the control samples. For 11 proteins, cofilin, C-reactive protein precursor, creatine kinase m-chain, fatty acid-binding protein, keratin type II, myosin light chain 2 and 3, nucleoside diphosphate kinase A, phosphoglycerate mutase 1, plakoglobulin, and retinoic acid-binding protein II, it is shown for the first time that they are differentially expressed in OSCC. Proteins with highly up-regulated levels may be of interest as potential diagnostic markers and consequently of clinical interest. 相似文献
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A New Structural Motif for an Enantiomerically Pure Metallosupramolecular Pd4L8 Aggregate by Anion Templating
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M. Sc. Christoph Klein Dr. Christoph Gütz Maximilian Bogner M. Sc. Filip Topić Prof. Dr. Kari Rissanen Prof. Dr. Arne Lützen 《Angewandte Chemie (International ed. in English)》2014,53(14):3739-3742
An enantiomerically pure BINOL‐based bis(3‐pyridyl) ligand 1 assembles into a homochiral [Pd4( 1 )8] complex upon coordination to tetravalent PdII ions. The formation of this aggregate is templated by two tetrafluoroborate counterions that are encapsulated in two peripheral cavities. The resulting structure is a new structural motif for this kind of metallosupramolecular assemblies that arranges the palladium ions in a distorted tetrahedral fashion and forces ligand 1 to adopt two different conformations. Both phenomena are unique and cause an overall three‐dimensional structure that has another confined, chiral, and hydrophilic central cavity. 相似文献
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AbstractOlive oils may provide health benefits, including the prevention of coronary heart diseases, cancers, and the modification of immune and inflammatory responses. These benefits mainly originate from the phenolic compounds found in olive oil. There has been no study on the advanced characterization of Albanian olive oils from various cultivars regarding phenolic compounds. Hence, a comprehensive characterization of phenolic compounds is carried out in Albanian monocultivar virgin olive oils from five different cultivars, including Kalinjot, Bardhi Tirana, Ulliri-i-Zi Tirana, Krips Kruja, and Bardhi Kruja for the first time. Liquid chromatography coupled to diode array detection and electrospray ?onization tandem mass spectrometry (LC-DAD-ESI-MS/MS) is employed for the determination of phenolic compounds. In total, 18 compounds were identified in all samples, including phenolic alcohols, phenolic acids, secoiridoids, flavonoids, and phenolic aldehydes. Significant quantitative differences were detected among the cultivars, with the highest concentrations detected in virgin olive oil (VOO) from cv. Ulli-i-Zi. Secoiridoids were found in abundance, in general, followed by phenolic alcohols, and in this group, 3,4-DHPEA-EDA and p-HPEA-EDA stood out as dominant compounds, especially in Kalinjot virgin olive oils. Regarding phenolic alcohols, 3,4-DHPEA-AC was determined as the main phenolic compound. Phenolic profiles were found to be significantly different among the olive oil samples of different cultivars. Principal component analyses (PCA) displayed the differentiation of samples in terms of phenolic compounds. 相似文献
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Dr. Lucia Volbach Dr. Niklas Struch Fabian Bohle Dr. Filip Topić Dr. Gregor Schnakenburg Andreas Schneider Prof. Dr. Kari Rissanen Prof. Dr. Stefan Grimme Prof. Dr. Arne Lützen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(15):3335-3347
Two isostructural ligands with either nitrile ( Lnit ) or isonitrile ( Liso ) moieties directly connected to a [2.2]paracyclophane backbone with pseudo-meta substitution pattern have been synthesized. The ligand itself ( Lnit ) or its precursors ( Liso ) were resolved by HPLC on a chiral stationary phase and the absolute configuration of the isolated enantiomers was assigned by XRD analysis and/or by comparison of quantum-chemical simulated and experimental electronic circular dichroism (ECD) spectra. Surprisingly, the resulting metallosupramolecular aggregates formed in solution upon coordination of [(dppp)Pd(OTf)2] differ in their composition: whereas Lnit forms dinuclear complexes, Liso exclusively forms trinuclear ones. Furthermore, they also differ in their chiral self-sorting behavior as (rac)- Liso undergoes exclusive social self-sorting leading to a heterochiral assembly, whereas (rac)- Liso shows a twofold preference for the formation of homochiral complexes in a narcissistic self-sorting manner as proven by ESI mass spectrometry and NMR spectroscopy. Interestingly, upon crystallization, these discrete aggregates undergo structural transformation to coordination polymers, as evidenced by single-crystal X-ray diffraction. 相似文献