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61.
In this note, we classify completely distributive CSLs up to approximate unitary equivalence. Our proof uses a new characterization of complete distributivity and leads to a generalization of a result of Arveson on ordered group lattices. As consequences of our results, we obtain a similarity theorem for hyperreflexive, completely distributive CSLs and some new perturbation results.Partially supported by an NSERC grantResearch partially supported by NSF grant DMS-9204811. 相似文献
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Dr. Ngong Kodiah Beyeh Dr. Fangfang Pan Acad. Prof. Kari Rissanen 《Angewandte Chemie (International ed. in English)》2015,54(25):7303-7307
Iodine (I2) acts as a bifunctional halogen‐bond donor connecting two macrocyclic molecules of the bowl‐shaped halogen‐bond acceptor, N‐cyclohexyl ammonium resorcinarene chloride 1 , to form the dimeric capsule [(1,4‐dioxane)3@ 1 2(I2)2]. The dimeric capsule is constructed solely through halogen bonds and has a single cavity (V=511 Å3) large enough to encapsulate three 1,4‐dioxane guest molecules. 相似文献
64.
Mark Maric Wilhelm van Bronswijk Kari Pitts Simon W. Lewis 《Journal of Raman spectroscopy : JRS》2016,47(8):948-955
The clear coats from a collection of automotive paint samples of 139 vehicles, covering a range of Australian and international vehicle manufacturers and sold in Western Australia, were characterised using FT‐Raman spectroscopy. Principal component analysis (PCA) revealed 19 distinct classes that were associated with the vehicles' manufacturer and model, and in the case of Australian manufacturers, the years of manufacture. Linear discriminant analysis based on the PCA groupings gave excellent discrimination between the groups with 96.9% of the calibration set and 97.6% of the validation set being correctly classified. Although the sample set comprised only vehicles available in Australia, the methodology used is universal and hence applicable in any jurisdiction that is willing and able to generate a statistically significant data set and maintain and update it as new vehicles appear on the market. A FT‐Raman spectroscopy‐based database would rapidly provide information regarding vehicle origin and manufacture and hence generate investigative leads for questioned paint samples found at incident sites. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Cody Ross Pitts Michelle Sheanne Bloom Desta Doro Bume Qinze Arthur Zhang Thomas Lectka 《Chemical science》2015,6(9):5225-5229
Expanding the repertoire of controlled radical fluorination techniques, we present a photosensitized unstrained C–C bond activation/directed monofluorination method using Selectfluor and 9-fluorenone. The reaction is amenable to the opening of multiple 1-acetal-2-aryl substituted rings to yield ω-fluoro carboxylic acids, esters, alcohols, and ketones with relative ease. Initial mechanistic insight suggests radical ion intermediates. 相似文献
66.
Parshintsev J Ruiz-Jimenez J Petäjä T Hartonen K Kulmala M Riekkola ML 《Analytical and bioanalytical chemistry》2011,400(10):3527-3535
In this research, the two most common filter media, quartz and Teflon, were tested to obtain information about the possible
adsorption of gas-phase compounds onto filters during long sample collection of atmospheric aerosols. Particles of nanometer-size
for off-line chemical characterization were collected using a recently introduced differential mobility analyzer for size
separation. Samples were collected at an urban site (Helsinki, SMEARIII station) during spring 2010. Sampling time was 4 to
10 days for particles 50, 40, or 30 nm in diameter. Sample air flow was 4 L/min. The sampling setup was arranged so that two
samples were obtained for each sampling period almost simultaneously: one containing particles and adsorbed gas-phase compounds
and one containing adsorbed gas-phase compounds only. Filters were extracted and analyzed for the presence of selected carboxylic
acids, polyols, nitrogen-containing compounds, and aldehydes. The results showed that, in quartz filter samples, gas-phase
adsorption may be responsible for as much as 100% of some compound masses. Whether quartz or Teflon, simultaneous collection
of gas-phase zero samples is essential during the whole sampling period. The dependence of the adsorption of gas-phase compounds
on vapor pressure and the effect of adsorption on the deposited aerosol layer are discussed. 相似文献
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The acid catalyzed hydrolytic cleavage of the oxazine rings in the readily available tetraoxazine derivatives of resorcinarenes results in tetraaminoresorcinarenes. A similar process applied to C2-symmetrical bisoxazine resorcinarene tetratosylates affords C2v-symmetrical resorcinarenediamines. The mild acylation of these resorcinareneamines with BOC-anhydride or para-nitrophenyl ester proceeds selectively at the nitrogen atoms without affecting the hydroxyl groups. Most of the resulting resorcinareneamides are thus obtained in preparative yields and can be easily purified by simple crystallizations. In the crystalline state the compounds obtained are found to bind chloride anions through hydrogen bonds and electrostatic interactions and to display a chiral arrangement of hydrogen bonded functional groups at the wide rim of the macrocycle. 相似文献