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11.
Langmuir films of binary mixtures of the following liquid crystal materials: 4-octyl-4′-cyanobiphenyl (8CB) or 4-pentyl-4″-cyano-p-terphenyl (5CT) with 4-(trans-4'-octylcyclohexyl)isothiocyanatobenzene (8CHBT), trans-4-octyl(4′-cyanophenyl)cyclohexane (8PCH) or 4-octyl4′-isothiocyanatobiphenyl (8BT) were investigated. Surface pressure-mean molecular area isotherms were recorded at various mixture compositions. It was found that only liquid crystal materials for which the molecules have a terminal -CN group are able to form a stable monolayer at the air-water interface. Moreover, information about the miscibility or the phase separation of the two components in the mixures was obtained by using the excess area criterion and surface phase rules. 相似文献
12.
Tomasz Girek 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(3-4):237-252
In the paper cyclodextrin-based (CD) polyrotaxanes are presented in the aspect of their syntheses and properties allowing various applications. The text consists of four parts, which describe CD-based polyrotaxanes with threads containing poly(ethylene oxide), poly (4,4′-diphenylenevinylene), polyfluorene and other chains. Conclusion shows new trends connected with this theme. 相似文献
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Tomasz Schoen 《Combinatorica》2015,35(6):695-701
We prove, in particular, that every finite subset A of an abelian group with the additive energy κ|A|3 contains a set A′ such that |A′|?κ|A| and |A′ ? A′|?κ ?4|A′|. 相似文献
15.
Dr. Szymon Chorazy Tomasz Charytanowicz Dr. Dawid Pinkowicz Junhao Wang Dr. Koji Nakabayashi Stephen Klimke Prof. Dr. Franz Renz Prof. Dr. Shin-ichi Ohkoshi Prof. Dr. Barbara Sieklucka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(36):15871-15879
A two-step hysteretic FeII spin crossover (SCO) effect was achieved in programmed layered Cs{[Fe(3-CNpy)2][Re(CN)8]}⋅H2O ( 1 ) (3-CNpy=3-cyanopyridine) assembly consisting of cyanido-bridged FeII-ReV square grid sheets bonded by Cs+ ions. The presence of two non-equivalent FeII sites and the conjunction of 2D bimetallic coordination network with non-covalent interlayer interactions involving Cs+, [ReV(CN)8]3− ions, and 3-CNpy ligands, leads to the occurrence of two steps of thermal SCO with strong cooperativity giving a double thermal hysteresis loop. The resulting spin-transition phenomenon could be tuned by an external pressure giving the room-temperature range of SCO, as well as by visible-light irradiation, inducing an efficient recovery of the high-spin FeII state at low temperatures. We prove that octacyanidorhenate(V) ion is an outstanding metalloligand for induction of a cooperative multistep, multiswitchable FeII SCO effect. 相似文献
16.
Two 3-silanyl-propenylphosphonate esters ( 1a , 1b ) were synthesized, and their deprotonation was attempted using RONa/ROH, RLi/THF, and LDA/THF systems. In the first two cases, the nucleophilic addition was the predominant (or exclusive) reaction observed; deprotonation was achieved with LDA, as confirmed by the reaction of the lithiated species with alkylating agents and with benzaldehyde. Chemical behavior of substrates 1 does not parallel closely that of the parent silanyl or phosphoryl-substituted allylic systems. © John Wiley & Sons, Inc. 相似文献
17.
Tomasz Bujak Martyna Zagrska-Dziok Aleksandra Ziemlewska Zofia Nizio-ukaszewska Kamila Lal Tomasz Wasilewski Zofia Hordyjewicz-Baran 《Molecules (Basel, Switzerland)》2022,27(3)
Flowers are a natural source of bioactive compounds that not only have antioxidant, anti-inflammatory, and anti-aging properties, but can also be used as natural dyes. For this reason, nowadays plants are widely used to produce natural cosmetics and foods. In these studies, the properties of the water extracts of Papaver rhoeas L., Punica granatum L., Clitoria ternatea L., Carthamus tinctorius L., and Gomphrena globosa L., as bioactive, natural dyes, were investigated. Plant flower extracts were tested for their antioxidant (ABTS and DPPH radical methods) and anti-inflammatory effects by determining the ability to inhibit the activity of lipoxygenase and proteinase. The extracts were tested for their cytotoxic effect on skin cells, using Alamar Blue and Neutral Red tests. The ability to inhibit the activity of enzymes responsible for the destruction of elastin and collagen was also studied. Research has shown that extracts have no toxic effect on skin cells, are a rich source of antioxidants and show the ability to inhibit the activity of elastase and collagenase enzymes. P. rhoeas extract showed the strongest antioxidant properties with IC50 value of 24.8 ± 0.42 µg/mL and 47.5 ± 1.01 µg/mL in ABTS and DPPH tests, respectively. The tested plants are also characterized by an anti-inflammatory property, for which the ability to inhibit lipoxygenase at a level above 80% and proteinase at the level of about 55% was noted. Extracts from P. rhoeas, C. ternatea, and C. tinctorius show the strongest coloring ability and can permanently dye cosmetic products, without significant color changes during the storage of the product. 相似文献
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19.
Simple-structured, well-functioned disposable poly(dimethylsiloxane) (PDMS) microchips were developed for capillary isoelectric focusing with whole column imaging detection (CIEF-WCID). Side-by-side comparison of the developed microchips with well-established commercial capillary cartridges demonstrated that the disposable microchips have comparable performance as well as advantages such as absence of lens effect and possibility of high-aspect-ratio accompanied with a dramatic reduction in cost. 相似文献
20.
We derive tight Bell's inequalities for N>2 observers involving more than two alternative measurement settings. We give a necessary and sufficient condition for a general quantum state to violate the new inequalities. The inequalities are violated by some classes of states, for which all standard Bell's inequalities with two measurement settings per observer are satisfied. 相似文献