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1.
Tibor Kelen Tibor Kelen Lajos Balogh Istvan Majoros Gyorgy Deak 《Macromolecular Symposia》1993,67(1):325-338
The possibilities of increasing the livingness in cationic isobutylene polymerizations has been investigated. It has been assumed that the living chain-end is polarized but non-dissociated and relatively stable, therefore, i) shifting of the dissociation equilibrium by adding salts with common or non-common anion in excess, and ii) increasing of the stability of the chain-end by complexing it with electrondonors, may increase the livingness of the system. Indeed, the addition of n-Bu4NCl or n-Bu4NI to systems with BCl3 or TiCl4 coinitiators, as well as the addition of dimethyl sulphoxide as electrondonor in a broad concentration range, improved the living character. The possibility of complexation of the chain-end by the monomer has also been supported 相似文献
2.
CM Thaker S Rayaprol Krushna Mavani DS Rana MS Sahasrabudhe SI Patil DG Kuberkar 《Pramana》2002,58(5-6):1035-1039
The effect of simultaneous substitution of a fluctuating cation and a divalent cation in LaMnO3 perovskite modifies the properties of the material to exhibit large valence colossal magnetoresistance (CMR) effect. A good
example of these properties is (La1−2x
Pr
x
Ca
x
)MnO3 (LPCMO) type CMR material. In this communication it is reported that, with the increase in x (for x=0.1, 0.15, 0.2), the T
c varies between 100 and 120 K with improvisation in metal-insulator transition. Interestingly, resistance increases with x from few hundred ohms to few kilo ohms with corresponding decrease in the unit cell volume. The results of the studies using
X-ray diffraction (XRD), electrical resistivity, magnetoresistance and ac susceptibility measurements on LPCMO samples for
understanding the structural, transport and magnetic properties are discussed in detail. 相似文献
3.
4.
The nanostructured (7 x 4) surface of SrTiO(3)(001) is used as a template to order C(70) into single-molecule-wide chains and linear islands. 相似文献
5.
Nagy N Deak A Hórvölgyi Z Fried M Agod A Barsony I 《Langmuir : the ACS journal of surfaces and colloids》2006,22(20):8416-8423
The validity of various effective medium approximations (EMAs) (Bruggeman, Maxwell-Garnett) was studied for nanostructured systems, where the scale of inhomogeneities is comparable to the wavelength. Langmuir-Blodgett (LB) layers of St?ber silica nanospheres of diameters between 40 and 129 nm are excellent model structures for the experimental verification of the validity of the EMA methods in spectroscopic ellipsometry (SE) evaluation. Nanostructured mono- and multilayered silica films were investigated by SE and reflectance spectroscopy. The effective refractive index and film thickness were determined from the results of multiparameter fitting of SE spectra in the 300-759 nm wavelength region. The distribution of the effective refractive index in the particulate films was calculated assuming an ideal close-packed arrangement of particles. The average deviation from such a structure was deduced from the corrected model by introducing a "fill factor". In the EMA approximation, the spherical shape of the silica particle determines the optical behavior, rather than the "depth distribution" of silica or porosity. Therefore, the shape of particles has a dominant effect on the optical properties of nanoparticulate LB films. 相似文献
6.
Michal Deak Krzysztof Kutak Konrad Tywoniuk 《The European Physical Journal C - Particles and Fields》2017,77(11):793
We propose a new framework, merging High Energy Factorization with final-state jet quenching effects due to interactions in a quark–gluon plasma, to compute di-jet rates at mid-rapidity and forward rapidity. It allows one to consistently study the interplay of initial-state effects with medium interactions, opening the possibility for understanding the dynamics of hard probes in heavy-ion collisions and the QGP evolution in rapidity. 相似文献
7.
M. Deak F. Hautmann H. Jung K. Kutak 《The European Physical Journal C - Particles and Fields》2012,72(4):1982
We observe that at the Large Hadron Collider, using forward + central detectors, it becomes possible for the first time to
carry out calorimetric measurements of the transverse energy flow due to “mini-jets” accompanying production of two jets separated
by a large rapidity interval. We present parton-shower calculations of energy flow observables in a high-energy factorized
Monte Carlo framework, designed to take into account QCD logarithmic corrections both in the large rapidity interval and for
hard transverse momentum. Considering events with a forward and a central jet, we examine the energy flow in the interjet
region and in the region away from the jets. We discuss the role of these observables to analyze multiple parton collision
effects. 相似文献
8.
Nguyen HN Cee VJ Deak HL Du B Faber KP Gunaydin H Hodous BL Hollis SL Krolikowski PH Olivieri PR Patel VF Romero K Schenkel LB Geuns-Meyer SD 《The Journal of organic chemistry》2012,77(8):3887-3906
Herein we describe a general three-step synthesis of 4-substituted chlorophthalazines in good overall yields. In the key step, N,N-dimethylaminophthalimide (8a) directs the selective monoaddition of alkyl, aryl, and heteroaryl organometallic reagents to afford 3-substituted 3-hydroxyisoindolinones 9b, 9i-9am. Many of these hydroxyisoindolinones are converted to chlorophthalazines 1b-1v via reaction with hydrazine, followed by chlorination with POCl(3). We have also discovered two novel transformations of 3-vinyl- and 3-alkynyl-3-hydroxyisoindolinones. Addition of vinyl organometallic reagents to N,N-dimethylaminophthalimide (8a) provided dihydrobenzoazepinediones 15a-15c via the proposed ring expansion of 3-vinyl-3-hydroxyisoindolinone intermediates. 3-Alkynyl-3-hydroxyisoindolinones react with hydrazine and substituted hydrazines to afford 2-pyrazolyl benzoic acids 16a-16d and 2-pyrazolyl benzohydrazides 17a-17g rather than the expected alkynyl phthalazinones. 相似文献
9.
J. Hladký M. Novák A. Prokeš J. Votruba V. I. Genchev V. D. Kekelidze V. G. Krivokhizhin V. V. Kukhtin M. F. Likhachev I. Manno I. A. Savin L. V. Silvestrov G. Vesztergombi K. -F. Albrecht A. Meyer H. -E. Ryseck M. Sachwitz F. Deak 《Czechoslovak Journal of Physics》1976,26(11):1290-1293
New experimental results on the coherentK
L
0
C K
S
0
C regeneration in the momentum range 10p30 GeV/c are presented. For the quantity (f
0–¯f
0/k (where f0 and¯f
0 are theKC and¯K
0C forward scattering amplitudes andk is the wave number) we have obtained: arg (f
0–¯f
0)/k=–126±14 and ¦(f
0–¯f
0/k¦ p
–0.62±0.14 These results are well described by a simple Regge pole model including only the (-trajectory exchange in thet-channel with the intercept (0) close to 0.4.Presented at the IV International Symposium on High Energy and Elementary Particle Physics, Warszaw, September 1975. 相似文献
10.