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141.
Harald Krautscheid Eberhard Matern Jolanta Olkowska‐Oetzel Jerzy Pikies Gerhard Fritz 《无机化学与普通化学杂志》2001,627(4):675-678
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXII. The Formation of [η2‐{tBu–P=P–SiMe3}Pt(PR3)2] from (Me3Si)tBuP–P=P(Me)tBu2 and [η2‐{C2H4}Pt(PR3)2] (Me3Si)tBuP–P = P(Me)tBu2 reacts with [η2‐{C2H4}Pt(PR3)2] yielding [η2‐{tBu–P=P–SiMe3}Pt(PR3)2]. However, there is no indication for an isomer which would be the analogue to the well known [η2‐{tBu2P–P}Pt(PPh3)2]. The syntheses and NMR data of [η2‐{tBu–P=P–SiMe3}Pt(PPh3)2] and [η2‐{tBu–P=P–SiMe3}Pt(PMe3)2] as well as the results of the single crystal structure determination of [η2‐{tBu–P=P–SiMe3}Pt(PPh3)2] are reported. 相似文献
142.
143.
Rony Snyders Christophe Roberges Marie-Pierre Faure Jolanta E. Klemberg-Sapieha 《Surface science》2007,601(1):112-122
We studied the mechanism of adhesion between N2 plasma treated polypropylene (PP/N2) backing and a hybrid hydrogel (HG) produced by chemical crosslinking between poly(ethylene glycol) and soy albumin. The work of adhesion, measured by peel testing, was found to be 25 times higher for PP/N2 compared to untreated PP (≈5.0 J/m2 versus ≈0.2 J/m2). In order to understand the adhesion mechanism, we performed a detailed analysis of the surface chemical composition of PP and PP/N2 using X-ray photoelectron spectroscopy (XPS), chemical derivatization and attenuated total reflectance infra-red (ATR-IR) measurements. The results confirm incorporation of different nitrogen- (amine, amide,…) and oxygen- (hydroxyl, carboxyl,…) containing chemical groups on the PP/N2 surface. The derivatized functions were primary amine, hydroxyl, carboxyl and carbonyl groups. Chemical derivatization reactions validated the XPS results (except for carbonyl groups), and they clearly underlined the essential role of primary amine groups in the adhesion process. In fact, after derivatization of the amine functions, the work of adhesion was found to be 0.41 ± 0.12 J/m2. Participation of amine groups in the formation of covalent bonds at the interface between PP/N2 and HG was directly confirmed by ATR-IR measurements. 相似文献
144.
Schlesinger PH Ferdani R Liu J Pajewska J Pajewski R Saito M Shabany H Gokel GW 《Journal of the American Chemical Society》2002,124(9):1848-1849
The design, synthesis, and characterization of a synthetic chloride membrane transporter, SCMTR (synthetic chloride membrane transporter, "scimitar"), are presented. The compound [CH3(CH2)17]2NCOCH2OCH2CO-GGGPGGG-OBzl inserts rapidly into liposomes and planar lipid bilayers. SCMTR has a 1.3 +/- 0.01 nS chloride diffusion pathway (>10:1 Cl/K selectivity). Evidence was also obtained for voltage gating behavior. 相似文献
145.
Mark J. Tobin Ljiljana Puskar Jafar Hasan Hayden K. Webb Carol J. Hirschmugl Michael J. Nasse Gediminas Gervinskas Saulius Juodkazis Gregory S. Watson Jolanta A. Watson Russell J. Crawford Elena P. Ivanova 《Journal of synchrotron radiation》2013,20(3):482-489
The wings of some insects, such as cicadae, have been reported to possess a number of interesting and unusual qualities such as superhydrophobicity, anisotropic wetting and antibacterial properties. Here, the chemical composition of the wings of the Clanger cicada (Psaltoda claripennis) were characterized using infrared (IR) microspectroscopy. In addition, the data generated from two separate synchrotron IR facilities, the Australian Synchrotron Infrared Microspectroscopy beamline (AS‐IRM) and the Synchrotron Radiation Center (SRC), University of Wisconsin‐Madison, IRENI beamline, were analysed and compared. Characteristic peaks in the IR spectra of the wings were assigned primarily to aliphatic hydrocarbon and amide functionalities, which were considered to be an indication of the presence of waxy and proteinaceous components, respectively, in good agreement with the literature. Chemical distribution maps showed that, while the protein component was homogeneously distributed, a significant degree of heterogeneity was observed in the distribution of the waxy component, which may contribute to the self‐cleaning and aerodynamic properties of the cicada wing. When comparing the data generated from the two beamlines, it was determined that the SRC IRENI beamline was capable of producing higher‐spatial‐resolution distribution images in a shorter time than was achievable at the AS‐IRM beamline, but that spectral noise levels per pixel were considerably lower on the AS‐IRM beamline, resulting in more favourable data where the detection of weak absorbances is required. The data generated by the two complementary synchrotron IR methods on the chemical composition of cicada wings will be immensely useful in understanding their unusual properties with a view to reproducing their characteristics in, for example, industry applications. 相似文献
146.
Magorzata Szczesio Andrzej Olczak Jolanta Goka Katarzyna Gobis Henryk Foks Marek L. Gwka 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(7):o235-o240
Methyl 2‐(pyrazin‐2‐ylcarbonyl)hydrazinecarbodithioate, C7H8N4OS2, (E1), N′‐[bis(methylsulfanyl)methylidene]pyrazine‐2‐carbohydrazide, C8H10N4OS2, (F1), N′‐[bis(methylsulfanyl)methylidene]‐6‐methoxypyrazine‐2‐carbohydrazide, C9H12N4O2S2, (F2), and methyl 1‐methyl‐2‐(pyrazin‐2‐ylcarbonyl)hydrazinecarbodithioate, C8H10N4OS2, (G1), can be considered as derivatives of classical (thio)amide‐type tuberculostatics, and all are moderately active against Mycobacterium tuberculosis. This study was undertaken in a search for relationships between activity and specific intramolecular interactions, especially conjugations and hydrogen‐bond contacts, and the molecular structures were compared with respective amine analogues, also active against the pathogen. Despite the differences between the amine and carbonyl groups with opposite functions in the hydrogen bond, the two types of structure show a surprisingly similar planar geometry, mostly due to the conjugations aided by the bifurcated intramolecular hydrogen‐bond contact between the N—H group of the central hydrazide group as donor and a pyrazine N atom and an S atom of the dithio function as acceptors. Planarity was suggested to be crucial for the tuberculostatic activity of these compounds. The N‐methylated derivative (G1) showed a significant twist at the N—N bond [torsion angle = −121.9 (3)°] due to the methyl substitution, which precludes an intramolecular N—H...S contact and the planarity of the whole molecule. Nonetheless, the compound shows moderate tuberculostatic activity. 相似文献
147.
Jolanta Kochana Katarzyna Hnida Grzegorz Sulka Paweł Knihnicki Joanna Kozak Agnieszka Gilowska 《Chemical Papers》2015,69(8):1130-1135
Polypyrrole nanowires (PPyNWs) were fabricated and examined as a structural component of amperometric biosensor matrix. An enzyme, tyrosinase (TYR), was immobilized onto PPyNWs using glutaraldehyde (GA). Matrix composite morphology was investigated using scanning electron microscopy. Electrochemical behavior of the prepared PPyNWs/GA/TYR biosensor towards catechol was studied and the assessment of its analytical characteristics was carried out taking into account linear range, sensitivity, repeatability, reproducibility and operational stability. 相似文献
148.
Ślęzak Andrzej Ślęzak-Prochazka Izabella Grzegorczyn Sławomir Jasik-Ślęzak Jolanta 《Transport in Porous Media》2017,116(2):941-957
Transport in Porous Media - S-entropy source of membrane system was described based on linear non-equilibrium thermodynamics. The volume and diffusive fluxes of non-electrolyte solutions and... 相似文献
149.
The Ramanujan Journal - It is known that among Siegel modular forms of degree 2 and level 1 the only functions that violate the Ramanujan conjecture are Saito–Kurokawa lifts of modular forms... 相似文献