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41.
A number of 4-n-nonylphenyl esters and mono- and di-fluorinated 4-n-nonylphenyl esters derived from 3-(4'-n-alkoxybiphenylyl)propanoic acids (II) have been synthesized and their thermotropic liquid crystal properties assessed with a view to obtaining tilted smectic phases for possible use in ferroelectric display devices. Many of these compounds exhibit wide temperature range SC and SI/F phases, but none gave the ideal phase sequence SC-SA-N-I mainly because the structure of these compounds was not conducive to the formation of the nematic phase. To try to alleviate this problem a series of 4-n-nonylphenyl esters based on 3-(4'-n-alkoxybiphenylyl)-3-methylpropanoic acid was prepared, where a lateral methyl group was incorporated in the β-position of the -CH2CH2CO2- linkage. Incorporation of the lateral methyl group encouraged the formation of a nematic phase at the expense of both the smectic A phase and tilted smectic phases. 相似文献
42.
H. H. Sutherland Z. Ali Adib G. W. Gray D. Lacey G. Nestor K. J. Toyne 《Liquid crystals》1988,3(10):1293-1300
A series of terminally cyano substituted side chain polysiloxanes have been characterized using optical microscopy, D.S.C., and X-ray diffraction. Values for the lamellar spacings, d, of the interdigitated smectic A phases were obtained, and the variations in d with temperature and length of the flexible aliphatic spacer are discussed. The spacing for m = 4, 5, and 6 increased regularly with m whereas the short m = 3 spacer gave an anomalously high value. 相似文献
43.
Enzymatic Electrosynthesis of Alkanes by Bioelectrocatalytic Decarbonylation of Fatty Aldehydes 下载免费PDF全文
Dr. Sofiene Abdellaoui Dr. Florika C. Macazo Rong Cai Dr. Antonio L. De Lacey Dr. Marcos Pita Prof. Shelley D. Minteer 《Angewandte Chemie (International ed. in English)》2018,57(9):2404-2408
An enzymatic electrosynthesis system was created by combining an aldehyde deformylating oxygenase (ADO) from cyanobacteria that catalyzes the decarbonylation of fatty aldehydes to alkanes and formic acid with an electrochemical interface. This system is able to produce a range of alkanes (octane to propane) from aldehydes and alcohols. The combination of this bioelectrochemical system with a hydrogenase bioanode yields a H2/heptanal enzymatic fuel cell (EFC) able to simultaneously generate electrical energy with a maximum current density of 25 μA cm?2 at 0.6 V and produce hexane with a faradaic efficiency of 24 %. 相似文献
44.
45.
Littleford RE Matousek P Towrie M Parker AW Dent G Lacey RJ Smith WE 《The Analyst》2004,129(6):505-506
The first use of Kerr gated fluorescence rejection Raman spectroscopy for the analysis of street samples of cocaine in a fluorescing matrix is reported. 相似文献
46.
Witzmann FA Bauer MD Fieno AM Grant RA Keough TW Lacey MP Sun Y Witten ML Young RS 《Electrophoresis》2000,21(5):976-984
We analyzed protein expression in the cytosolic fraction prepared from whole kidneys in male Swiss-Webster mice exposed 1 h/day for five days to aerosolized JP-8 jet fuel at a concentration of 1000 mg/m3, simulating military occupational exposure. Kidney cytosol samples were solubilized and separated via large-scale, high-resolution two-dimensional electrophoresis (2-DE) and gel patterns scanned, digitized and processed for statistical analysis. Significant changes in soluble kidney proteins resulted from jet fuel exposure. Several of the altered proteins were identified by peptide mass finger-printing and related to ultrastructural abnormalities, altered protein processing, metabolic effects, and paradoxical stress protein/detoxification system responses. These results demonstrate a significant but comparatively moderate JP-8 effect on protein expression in the kidney and provide novel molecular evidence of JP-8 nephrotoxicity. Human risk is suggested by these data but conclusive assessment awaits a noninvasive search for biomarkers in JP-8 exposed humans. 相似文献
47.
Capon RJ Vuong D McNally M Peterle T Trotter N Lacey E Gill JH 《Organic & biomolecular chemistry》2005,3(1):118-122
The principle nematocidal agent present in a southern Australian marine sponge of the genus Echinodictyum has been isolated and identified as the novel betaine (+)-echinobetaine B (6), and the structure assigned by spectroscopic analysis has been confirmed by total synthesis. Preliminary SAR conclusions are drawn from analysis of synthetic intermediates and the known marine metabolites zooanemonin (12) and norzooanemonin (13), and the new sponge metabolite norzooanemonin methyl ester (14). The latter compound is reported for the first time from a selection of Australian sponges, including an Axinyssa sp., a Niphates sp., an Axinella sp. and a Ptilocaulis sp. 相似文献
48.
Optimized procedures have been developed for the addition of sulfonic acid groups to the N-termini of low-level peptides. These procedures have been applied to peptides produced by tryptic digestion of proteins that have been separated by two-dimensional (2-D) gel electrophoresis. The derivatized peptides were sequenced using matrix-assisted laser desorption/ionization (MALDI) post-source decay (PSD) and electrospray ionization-tandem mass spectrometry methods. Reliable PSD sequencing results have been obtained starting with sub-picomole quantities of protein. We estimate that the current PSD sequencing limit is about 300 fmol of protein in the gel. The PSD mass spectra of the derivatized peptides usually allow much more specific protein sequence database searches than those obtained without derivatization. We also report initial automated electrospray ionization-tandem mass spectrometry sequencing of these novel peptide derivatives. Both types of tandem mass spectra provide predictable fragmentation patterns for arginine-terminated peptides. The spectra are easily interpreted de novo, and they facilitate error-tolerant identification of proteins whose sequences have been entered into databases. 相似文献
49.
50.
H. H. Sutherland Z. Ali Adib G. W. Gray D. Lacey G. Nestor K. J. Toyne 《Liquid crystals》2013,40(10):1293-1300
Abstract A series of terminally cyano substituted side chain polysiloxanes have been characterized using optical microscopy, D.S.C., and X-ray diffraction. Values for the lamellar spacings, d, of the interdigitated smectic A phases were obtained, and the variations in d with temperature and length of the flexible aliphatic spacer are discussed. The spacing for m = 4, 5, and 6 increased regularly with m whereas the short m = 3 spacer gave an anomalously high value. 相似文献