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排序方式: 共有1032条查询结果,搜索用时 15 毫秒
1.
Tadeusz Biedro Przemysaw Kubisa 《Journal of polymer science. Part A, Polymer chemistry》2004,42(13):3230-3235
The cationic polymerization of styrene in a neutral ionic liquid, 1‐butyl‐3‐methylimidazolium hexafluorophosphate, with a 1‐phenetyl chloride/TiCl4 initiating system is reported. The polymerization proceeds to a high conversion, but an analysis of the matrix‐assisted laser desorption/ionization time‐of‐flight spectra of the polymers indicates that chain transfer is significant, leading to a lack of control over the molecular weight and molecular weight distribution. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3230–3235, 2004 相似文献
2.
Sun G Kappl M Pakula T Kremer K Butt HJ 《Langmuir : the ACS journal of surfaces and colloids》2004,20(19):8030-8034
Forces across polymer melts are poorly understood despite their importance for adhesion and fabricating composite materials. Using an atomic force microscope (AFM), this interaction was measured for poly(dimethyl siloxane) (PDMS). The structure of the polymer at the surface changed during the first approximately 10 h. Afterward, short-range attractive forces were observed with short-chain PDMS (M(w) = 4200 g/mol). Using PDMS with a molecular weight (M(w) = 18 000 g/mol) above the entanglement limit, we measured a monotonically decaying repulsive force, which indicates that a quasi-immobilized layer had formed at the solid surface. Due to the small radius of curvature of the tip, forces could be measured in equilibrium. 相似文献
3.
Tadeusz Bednarski 《Probability Theory and Related Fields》1981,58(3):397-405
Summary Solutions to minimax test problems between neighbourhoods generated by specially defined capacities are discussed. The capacities are superpositions of probability measures and concave functions, so the paper covers most of the earlier results of Huber and Rieder concerning minimax testing between -contamination and total variation neighbourhoods. It is shown that the Neyman-Pearson lemma for 2-alternating capacities, proved by Huber and Strassen, can be applied to test problems between noncompact neighbourhoods of probability measures. It turns out that the Radon-Nikodym derivative between the special capacities is usually a nondecreasing function of the truncated likelihood ratio of some probability measures. 相似文献
4.
Teresa Olszewska Maria J. Milewska Maria Gdaniec Tadeusz Połoński 《Tetrahedron: Asymmetry》2012,23(3-4):278-283
The crystal structures of several bicyclic N-nitrosamines indicate that they crystallize in the chiral (Sohncke) space group P212121 as conglomerates. This allows the resolution of these compounds by manual picking of the enantiomorphous crystals. The optical activity of the single crystals was confirmed by their CD spectra taken in KBr disks. The absolute configurations of the title nitrosamines were assigned by crystallographic measurements and by a comparison of their CD spectra with those of a reference compound resolved by classical methods. The observed Cotton effect signs, corresponding to the n–π1 transition, were correlated with the helicity of the inherently chiral nitrosamine chromophore. 相似文献
5.
Tadeusz Balaban Michael O'Carroll Ricardo Schor 《Communications in Mathematical Physics》1989,122(2):233-247
Block renormalization group transformations (RGT) for lattice and continuum Euclidean Fermions in d dimensions are developed using Fermionic integrals with exponential and -function weight functions. For the free field the sequence of actionsD
k
generated by the RGT from D, the Dirac operator, are shown to have exponential decay; uniform ink, after rescaling to the unit lattice. It is shown that the two-point functionD
–1 admits a simple telescopic sum decomposition into fluctuation two-point functions which for the exponential weight RGT have exponential decay. Contrary to RG intuition the sequence of rescaled actions corresponding to the -function RGT do not have uniform exponential decay and we give examples of initial actions in one dimension where this phenomena occurs for the exponenential weight RGT also. 相似文献
6.
Tadeusz Bałaban 《Communications in Mathematical Physics》1983,88(3):411-445
This is the third paper of a series, and contains a proof of the bounds on the effective actions needed in the two previous papers. The proof is based on perturbative analysis of renormalization. 相似文献
7.
This paper presents a developed theory of computations
and analysis of piezoelectric photothermal amplitude and phase spectra of
semiconductors with surface defects states on one or both surfaces of the
sample exhibiting energies in the energy gap region of a semiconductor. The
theory comprises considerations of the front and rear experimental
configurations. The presented theory is the extension of the Jackson–Amer
model for the case of many optically generated and spatially separated heat
sources. 相似文献
8.
Tadeusz Bałaban 《Communications in Mathematical Physics》1987,109(2):249-301
We study four-dimensional pure gauge field theories by the renormalization group approach. The analysis is restricted to small field approximation. In this region we construct a sequence of localized effective actions by cluster expansions in one step renormalization transformations. We construct also -functions and we define a coupling constant renormalization by a recursive system of renormalization group equations. 相似文献
9.
Tadeusz Antczak 《Journal of Mathematical Analysis and Applications》2003,286(1):187-206
Invexity of a function is generalized. The new class of nonconvex functions, called B-(p,r)-invex functions with respect to η and b, being introduced, includes many well-known classes of generalized invex functions as its subclasses. Some properties of the introduced class of B-(p,r)-invex functions with respect to η and b are studied. Further, mathematical programming problems involving B-(p,r)-invex functions with respect to η and b are considered. The equivalence between saddle points and optima, and different type duality theorems are established for this type of optimization problems. 相似文献
10.
A unique bit-edge equalization (BEE) method for mitigating intersymbol interference (ISI) in high-speed backplane applications is presented. Using a least-mean-square (LMS) adaptive algorithm as a receiver (RX) error convergence engine, the proposed BEE method aims to optimize the bit-edge amplitudes by equalizing only the edges of data bits with an adjustment of the sampling points where the error information is collected. This adjustment of sampling points in turn changes the error information and affects filter coefficients for pulse amplitude modulation. As a result, the channel's far-end 3-level bit-edge eye diagrams can be optimized. This proposed BEE method employs transmitter (TX) pre-coding in conjunction with TX pre-emphasis using a symbol-spaced FIR (SSF) filter. In this work, a detailed analytical comparison of the proposed BEE transceiver architecture with the conventional NRZ bit-centre equalization (BCE) and duobinary transceiver architectures is presented. The simulation results demonstrate that at 10+ Gbps data rates, the proposed BEE is the most effective method for mitigating ISI in relatively high-loss channels. 相似文献