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91.
Horton JM Bao C Bai Z Lodge TP Zhao B 《Langmuir : the ACS journal of surfaces and colloids》2011,27(21):13324-13334
This article reports on the synthesis of thermo- and pH-sensitive polymer-brush-grafted silica particles ("hairy" particles) and the study of their phase-transfer behavior between water and a hydrophobic ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMIM][TFSA]), in response to temperature and pH changes. The hairy particles were made by the surface-initiated atom transfer radical polymerization of methoxytri(ethylene glycol) methacrylate (TEGMMA) and tert-butyl methacrylate with a molar ratio of 100:11 in the presence of a free initiator and the subsequent removal of tert-butyl groups. The cloud points (CPs) of poly(TEGMMA-co-methacrylic acid), obtained after the treatment of the free polymer with trifluoroacetic acid, in both water and [EMIM][TFSA]-saturated water increased with the increase in pH and can be tuned over a wide temperature range. The hairy particles moved spontaneously from the aqueous phase to the [EMIM][TFSA] phase upon heating at 80 °C and returned to the aqueous layer upon cooling at 10 °C. This process can be repeated many times regardless of whether the pH of the aqueous phase is 2.99, 5.00, or 7.02. UV-vis absorbance measurements showed that the transfer temperature (T(tr)) of hairy particles from water to [EMIM][TFSA] increased with the increase in the pH of the aqueous phase. A linear relationship was observed between the T(tr) of hairy particles and the CP of the corresponding free polymer. By taking advantage of the tunability of the T(tr) of hairy particles, we demonstrated the pH-driven reversible transfer of hairy particles at a fixed temperature by changing the pH of the aqueous phase and multiple phase-transfer processes by controlling both the temperature and pH. 相似文献
92.
Functionalism about truth is the view that truth is an explanatorily significant but multiply-realizable property. According
to this view the properties that realize truth vary from domain to domain, but the property of truth is a single, higher-order,
domain insensitive property. We argue that this view faces a challenge similar to the one that Jaegwon Kim laid out for the
multiple realization thesis. The challenge is that the higher-order property of truth is equivalent to an explanatorily idle
disjunction of its realization bases. This consequence undermines the alethic functionalists’ non-deflationary ambitions.
A plausible response to Kim’s argument fails to carry over to alethic functionalism on account of significant differences
between alethic functionalism and psychological functionalism. Lynch’s revised view in his book Truth as One and Many (2009) fails to answer our challenge. The upshot is that, while mental functionalism may survive Kim’s argument, it mortally wounds
functionalism about truth. 相似文献
93.
94.
Virendra C. Bhavsar Uday G. Gujar Joseph D. Horton Lambros A. Lambrou 《BIT Numerical Mathematics》1990,30(2):257-267
The discrepancy of a pseudo-random number (PRN) sequence has been defined as a quantity which measures the deviation of the sequence's distribution from the ideal uniform distribution. In this paper, we give three algorithms for computer evaluation of the discrepancy of PRN sequences. The computational results for the discrepancy of PRN sequences generated by a linear congruential method are included.This research is partially funded by Natural Sciences and Engineering Research Council of Canada, Grant No. 0GP00089. A research grant from IBM Canada through the Supercomputer Center, University of New Brunswick, is gratefully acknowledged. 相似文献
95.
96.
97.
M. Odlyha Q. Wang G. M. Foster J. de Groot M. Horton L. Bozec 《Journal of Thermal Analysis and Calorimetry》2005,82(3):627-636
Dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC) and thermogravimetry (TG) have been used
to characterise model tapestries, especially woven for the EC-funded project (MODHT) and to historic tapestries in royal palaces
and museums. Modulus values of woollen threads from model tapestries are reported and the effects of traditional dyeing and
mordanting processes quantified. TG, particularly of black woollen threads showed alterations in thermal stability. Tests
of creep on immersion in water and subsequent heating to 90°C and on exposure to a controlled relative humidity programme
were also used to rank these effects. Modulus values of historic woollen samples were also obtained and DSC studies of model
and historic silk samples are reported together with preliminary atomic force microscopy (AFM) images of silk fibres. 相似文献
98.
Nguyen HL Horton PN Hursthouse MB Legon AC Bruce DW 《Journal of the American Chemical Society》2004,126(1):16-17
It is shown for the first time that liquid crystal behavior can be induced through halogen bonding. Thus, mixing the nonmesomorphic components 4-alkoxystilbazole with pentafluoroiodobenzene leads to a 1:1 halogen-bonded complex whose integrity is shown by X-ray single-crystal analysis and which shows thermotropic smectic A and nematic phases. 相似文献
99.
The nature of art lends itself to forgery as a skilled and determined forger can mimic the techniques and styles of an artist to a level where even an expert can be duped. The authentication of paintings is a subjective process, but modern techniques may provide the means to provenance artist pigments based on elemental composition. This study applies laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to the analysis of artist paints from different manufacturers to identify variation between the elemental association patterns of these materials. The technique facilitates comparison of the paints used by an artist with produced works of art to assist provenancing initiatives of questioned materials. The effects of the trace element profiles of the backing substrate and binder on analytical data were also identified. By applying the technique to paint scraped from real paintings, a limited database was created to allow comparison to be made with some of Australian artist, Kathleen O’Connor's artworks and assist in determining production chronology. Data from this study were able to facilitate comparison of blue paints from two different paintings and confirm their co-provenance consequently determining the relative production date of a separate painting of previously unknown age.Preliminary trials of a prototype collection device designed to reduce damage and allow for in situ sampling of artworks were also undertaken. The device, which allows direct laser-based sampling of a complete painting, was tested using a Francis Ryan painting. The prototype allows for the collection of debris directly generated by LA-ICP-MS of a predefined area of a painting prior to subsequent analysis using direct LA-ICP-MS. This collection method significantly minimizes the amount of damage produced by conventional sampling methods. Analyses of the debris collected, using the prototype, were found to be comparable to the scrapings of equivalent paint analysed using direct LA-ICP-MS analysis. 相似文献
100.
Mountford AJ Lancaster SJ Coles SJ Horton PN Hughes DL Hursthouse MB Light ME 《Inorganic chemistry》2005,44(16):5921-5933
The reaction between B(C(6)F(5))(3) and NH(3)(g) in light petroleum yielded the solvated adduct H(3)N.B(C(6)F(5))(3).NH(3). Treatment with a second equivalent of B(C(6)F(5))(3) afforded H(3)N.B(C(6)F(5))(3). Attempts to prepare the analogous alane adduct were unsuccessful and resulted in protolysis. Related compounds of the form R'R' 'N(H).M(C(6)F(5))(3) were synthesized from M(C(6)F(5))(3) and the corresponding primary and secondary amines (M = B, Al; R' = H, Me, CH(2)Ph; R' ' = Me, CH(2)Ph, CH(Me)(Ph); R'R' ' = cyclo-C(5)H(10)). The solid-state structures of 13 new compounds have been elucidated by single-crystal X-ray diffraction and are discussed. Each of the borane adducts has a significant bifurcated intramolecular hydrogen bond between an amino hydrogen and two o-fluorines, while N-H...F-C interactions in the alane adducts are weaker and more variable. (19)F NMR studies demonstrate that the borane adducts retain the bifurcated C-F...H...F-C hydrogen bond in solution. Compounds of the type R'R' 'N(H).M(C(6)F(5))(3) conform to Etter's rules for the prediction of hydrogen-bonding interactions. 相似文献