Search results for "imide"
showing 10 items of 298 documents
Estimation of interfacial fracture toughness based on progressive edge delamination of a thin transparent coating on a polymer substrate
2010
Evaluation of interfacial toughness of sub-micron-thickness layers deposited on a ductile substrate is a challenging task which has motivated different experimental approaches Fragmentation testing was used in the present study as a means of interface characterization of a silicon-nitride-coated polyimide substrate. During the test, after an initial rapid segmentation-cracking phase, the coating fragments developed edge delaminations which propagated in a stable manner with further increase in the applied strain The debonding process was modelled by the finite element method Incorporating a cohesive zone at the front of the interfacial crack The edge cracks were found to be dominated by mod…
Killer toxin producing strains of the yeasts Hanseniaspora uvarum and Pichia kluyveri
1988
By heat treatment killer strains of the type K1 of Saccharomyces cerevisiae that are known to harbour dsRNA plasmids were completely cured, whereas only a small fraction of the clones of the killer type K2 had lost the dsRNA dependent killer character. The K2 killers but not the strains of killer type K1 were easily cured by cycloheximide. Killer strains of Hanseniaspora uvarum were not curable by heat treatment. Curing was successfull with cycloheximide or 5-fluorouracil. Two double-stranded RNA plasmids were detected in the killer strains of H. uvarum. The smaller dsRNA plasmid was absent in the strains that were cured of their killer character by 5-fluorouracil. The killer character of H…
Stability of phospholipase D in primary astrocytes.
2002
Induction of expression and proteolytic breakdown of phospholipase D (PLD) isoforms in primary astrocyte cultures have been investigated. Astrocytes express both PLD1 and 2 and are dependent on PLD activity for cell proliferation [K. Kotter, J. Klein, J. Neurochem. 73 (1999) 2517]. Competitive RT-PCR analysis demonstrated a higher level of PLD1 mRNA than PLD2 mRNA (8.9 vs. 0.9amol/microg RNA, respectively). Treatment of astroglial cultures with the phorbol ester, 4beta-phorbol-12beta,13alpha-dibutyrate (0.1 microM), for 24-48h selectively induced PLD1b but not PLD1a or 2 expression as shown by PCR and Western blot; the effect was sensitive to Go 6976. In cells transiently permeabilized with…
Destabilized green fluorescent protein detects rapid removal of transcription blocks after genotoxic exposure
2007
High stabilities of reporter proteins and their messenger RNAs (mRNAs) interfere with the detection of rapid transient changes in gene expression, such as transcriptional blocks posed by genotoxic DNA lesions. We have modified a green fluorescent protein (GFP) gene within the episomal pMARS vector by addition of a fragment encoding for mouse ornithine decarboxylase (ODC) proline-glutamate-serine-threonine-rich (PEST) sequence in order to target the protein to the proteasomes and achieved an unprecedentedly fast GFP turnover in permanently transfected human cells. As early as 1 h after inhibition of protein synthesis by cycloheximide, the number of fluorescent cells decreased more than 5-fo…
The quantitative determination of metabolites of 6-mercaptopurine in biological materials. VII. Chemical synthesis by phosphorylation of 6-thioguanos…
1990
Abstract A fast and reliable two-step method has been established for the chemical synthesis of 6-thioguanosine 5′-monophosphate, 6-thioguanosine 5′-diphosphate and 6-thioguanosine 5′-triphosphate starting from the ribonucleoside. In the first step, 6-thioguanosine dissolved in triethyl phosphate, at high yield reacts with phosphorus oxide trichloride to 6-thioguanosine 5′-monophosphate which is purified by anion-exchange chromatography on DEAE-Sephadex using a step gradient of hydrochloric acid. In the second step, 6-thioguanosine 5′-monophosphate dissolved in water, reacts with phosphoric acid in the presence of pyridine/dicyclohexyl carbodiimide and is converted to 6-thioguanosine 5′-dip…
Study of liquid–liquid equilibria at different temperatures of water + ethanol + 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide tern…
2016
Abstract The experimental liquid–liquid equilibria (LLE) data of the water + ethanol + 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([bmp][Tf2N]) system has been measured at different temperatures in this work. The LLE of the system has been measured at between 283 and 333 K. The UNIQUAC and NRTL models were used to correlate the LLE data and good results were obtained in both cases, however UNIQUAC gave a more accurate correlation. In order to apply the UNIQUAC model the volume and surface parameters for [bmp][Tf2N] (r, q) were determined. Finally, in order to obtain ethanol from the aqueous mixture, the solvent capability of the ionic liquid was checked and compared wit…
Capability study of 1-butyl-3- methylimidazolium bis(trifluoromethylsulfonyl)imide and trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phos…
2018
Abstract The liquid-liquid equilibria of the ternary systems water (1) + 1-propanol (2) + 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][Tf2N]) (3) and water (1) + 1-propanol (2) + trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate ([TDTHP][Phosph]) (3) at 283.2, 303.2 and 323.2 K and atmospheric pressure were determined to study their behaviour, determine their thermodynamic parameters and know the capability as solvents of [bmim][Tf2N] and [TDTHP][Phosph] in the separation of the azeotropic mixture water + 1-propanol. The non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models were used in the calculation of the thermodynamic par…
Study of the capability of 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquid as solvent in the separation of water from 1-pr…
2020
Abstract After the good behavior of different 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquids (ILs) used as solvents in the separation of 1-propanol and 2-propanol from water, liquid-liquid equilibria data was measured from a system formed by a ternary mixture of water, 1-propanol or 2-propanol and 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([dmim][Tf2N]) at 283.2, 303.2 and 323.2 K and atmospheric pressure. The non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models were employed to obtain the thermodynamic parameters of both ternary mixtures, with good results in all cases. Finally, the capability of [dmim][Tf2N] to separate…
Liquid–Liquid Equilibria of Water + Ethanol + 1-Butyl-3-methylimidazolium Bis(trifluoromethanesulfonyl)imide Ternary System: Measurements and Correla…
2015
In this work authors present the experimental liquid–liquid equilibria (LLE) data of water + ethanol + 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([bmim][Tf2N]) system at different temperatures. The LLE of the system was obtained in the temperature range from 283.2 to 323.2 K. The nonrandom two liquid (NRTL) and universal quasichemical (UNIQUAC) models were used to correlate ternary systems. The equilibrium compositions were successfully correlated by the interaction parameters from both models, however UNIQUAC gave a more accurate correlation. Finally, a study about the solvent capability of ionic liquid was made in order to evaluate the possibility of separating the mi…
Influence of double infections on the induction of thymidine kinase by UV-irradiated herpes simplex virus types 1 and 2 and pseudorabies virus
1975
Simultaneous infection of primary rabbit kidney cells with HSV type 1 TK+ and a TK- strain results in a mutual influence of both viruses on the induction of thymidine kinase (TK). TK+ virus has an enhancing and TK- virus a depressing effect on TK induction by a superinfecting TK+ virus. The enzyme induction depends on the ratio of multiplicities of both viruses. The mutual influence on TK induction depends further on the time of addition of the superinfecting virus: the effect of the second virus can still be observed when given 6 hours after primary infection. Identical phenomena can be observed using combinations with HSV type 2 or Pseudorabies viruses. The ability of HSV to induce TK is …