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131.
Sakai N Lista M Kel O Sakurai S Emery D Mareda J Vauthey E Matile S 《Journal of the American Chemical Society》2011,133(39):15224-15227
Facile access to complex systems is crucial to generate the functional materials of the future. Herein, we report self-organizing surface-initiated polymerization (SOSIP) as a user-friendly method to create ordered as well as oriented functional systems on transparent oxide surfaces. In SOSIP, self-organization of monomers and ring-opening disulfide exchange polymerization are combined to ensure the controlled growth of the polymer from the surface. This approach provides rapid access to thick films with smooth, reactivatable surfaces and long-range order with few defects and high precision, including panchromatic photosystems with oriented four-component redox gradients. The activity of SOSIP architectures is clearly better than that of disordered controls. 相似文献
132.
Kajitani T Onouchi H Sakurai S Nagai K Okoshi K Onitsuka K Yashima E 《Journal of the American Chemical Society》2011,133(24):9156-9159
We report a unique macromolecule consisting of a rodlike helical polyisocyanide backbone with a narrow molecular weight distribution and rigid mesogenic chiral pendants linked via a flexible spacer that exhibits lyotropic nematic and latticelike new smectic (lat-Sm) liquid crystal phases at different concentrations. The unprecedented lat-Sm phase is associated with the smectic ordering of both the stiff polymer backbone and the rigid-rod side groups. A detailed investigation of the films using X-ray scattering and atomic force microscopy revealed a novel tilted smectic layer structure of the polymer backbone aligned perpendicular to the smectic layer of the mesogenic pendants, which arrange in an antiparallel overlapping interdigitated manner. 相似文献
133.
Treatment of perylene bisimides (PBIs) with bis(pinacolato)diboron in the presence of an iridium catalyst provides tetraborylated PBIs at 2,5,8,11-positions in good yields with perfect regioselectivity. The planar structure of the perylene core has been confirmed by X-ray diffraction analysis. Oxidation of tetraborylated PBI with hydroxylamine hydrochloride affords tetrahydroxy PBI in excellent yield, which exhibits a substantially blue-shifted absorption spectrum due to an intramolecular hydrogenbonding interaction between carbonyl and hydroxy groups. 相似文献
134.
We have investigated the effect of co-absorbed CO and reaction temperature on the angular distribution of N(2) desorption by N(2)O decomposition under the steady state of N(2)O-CO reaction on Rh(110). Spatial distributions of desorbing product N(2) emission have been measured at various surface temperatures and CO coverages. The decomposed N(2) collimates at 48°-61° off normal in the parallel plane to [001] and [110] directions, indicating that adsorbed N(2)O just before the decomposition is oriented along the [001] direction. Although the inclined and collimated N(2) desorption is always observed at any steady-state CO coverage and reaction temperature, the shape of the collimated N(2) distribution varied dependent on the co-adsorbed CO coverage. The distribution becomes sharp and shifts toward the surface normal direction with increasing CO coverage. These effects of adsorbed CO on the angular distribution of N(2) are interpreted by the collision of desorbed N(2) with co-adsorbed CO. 相似文献
135.
Jin Q Ikeda T Fujishima M Tada H 《Chemical communications (Cambridge, England)》2011,47(31):8814-8816
The electronic modification of TiO(2) with highly dispersed NiO particles smaller than ca. 2 nm by the chemisorption-calcination-cycle technique has given rise to a high level of visible-light-activity exceeding that of iron oxide-surface modified TiO(2) simultaneously with the UV-light-activity being significantly increased. 相似文献
136.
This paper investigates the flow field near three intersecting shock waves appearing in steady Mach reflection. Results of
numerical computations reveal a “von Neumann Paradox”—like feature for weak shock waves, in which the flow field between the
reflected and the Mach stem is smooth with no distinct slip flow region and changes rather smoothly. An analytical solution
of the Navier–Stokes equations constructed using a polar–coordinate system gives a flow field with the same properties as
the numerical simulation. 相似文献
137.
Yasunori Fujikoshi Tamio Kan Shin Takahashi Tetsuro Sakurai 《Annals of the Institute of Statistical Mathematics》2011,63(2):387-403
Several criteria, such as CV, C
p
, AIC, CAIC, and MAIC, are used for selecting variables in linear regression models. It might be noted that C
p
has been proposed as an estimator of the expected standardized prediction error, although the target risk function of CV
might be regarded as the expected prediction error R
PE. On the other hand, the target risk function of AIC, CAIC, and MAIC is the expected log-predictive likelihood. In this paper,
we propose a prediction error criterion, PE, which is an estimator of the expected prediction error R
PE. Consequently, it is also a competitor of CV. Results of this study show that PE is an unbiased estimator when the true model
is contained in the full model. The property is shown without the assumption of normality. In fact, PE is demonstrated as
more faithful for its risk function than CV. The prediction error criterion PE is extended to the multivariate case. Furthermore,
using simulations, we examine some peculiarities of all these criteria. 相似文献
138.
A germacalix‐crown, 25,27‐bis[1‐(3‐trimethylgermylpropyl)oxy]calix[4]arene‐crown‐6, 1,3‐alternate ( 1a ), and its carbon analog, 25,27‐bis‐[1‐(4,4‐dimethylpentyl)oxy]calix[4]arene‐crown‐6, 1,3‐alternate ( 1b ), were prepared and their structures were confirmed by elemental analysis and 1H and 13C NMR spectroscopy. A cation transport test indicated that both compounds exhibited much the same cation transport ability, so that the role of the germanium moiety in capturing and transporting counteranions is not yet clear. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
139.
H. Iwasaki T. Motobayashi H. Akiyoshi Y. Ando N. Fukuda H. Fujiwara Zs. Fülöp K. I. Hahn Y. Higurashi M. Hirai I. Hisanaga N. Iwasa T. Kijima A. Mengoni T. Minemura T. Nakamura M. Notani S. Ozawa H. Sagawa H. Sakurai S. Shimoura S. Takeuchi T. Teranishi Y. Yanagisawa M. Ishihara 《The European Physical Journal A - Hadrons and Nuclei》2002,13(1-2):55-58
Experimental studies on in-beam γ-ray spectroscopy using a 12Be radioactive beam are presented. Inelastic scattering of the neutron-rich 12Be nucleus on 208Pb, 12C, and (CH2)n targets has been studied by measuring de-excitation γ-rays in coincidence with scattered particles. The level schemes and
transition probabilities are determined for low-lying excited states in 12Be. The present paper presents a brief review of the spectroscopic results, which may be associated with the N = 8 shell quenching near the drip line.
Received: 1 May 2001 / Accepted: 4 December 2001 相似文献
140.
H.S. Margolis J. Asada T.V. Back D.J. Bieber F.J. Currell E.G. Myers N. Nakamura S. Ohtani P.K. Oxley M. Sakurai J.D. Silver H. Watanabe 《Hyperfine Interactions》1998,112(1-4):139-142
The presence of the σ-phase in Fe-Cr alloys (eg. Stainless steel) is important in industrial applications and from an academic
point of view. The presence of the σ-phase in these alloys drastically affects their mechanical properties and their resistance
to various corrosive media. In the present investigation Fe-Cr alloys containing different amounts of Mo were prepared and
the transformation to the σ-phase was carried out by isothermally annealing the samples for various periods in an argon atmosphere.
It will be shown that the presence of Mo has a dramatic accelerating effect on the rate of the σ-phase formation in these
alloys.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献