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1.
The chiral ordering in aggregated poly(3-alkylthiophene) can be controlled by a metal salt-dependent doping-dedoping process. Enhancement or reduction in the chiral anisotropy factor depends on the doping level, such that doping driven by polymer-metal salt interactions, and dedoping driven by aggregate formation must be balanced in order to achieve maximal chiral ordering. This phenomenon provides a new basis to control chiral arrangement in conjugated polymer aggregates, relying solely on doping, and thus avoiding tedious modification of side-chain or main-chain structures.  相似文献   
2.
A convenient procedure for the preparation of some new germasesquioxides containing phosphonyl groups carried by an intramolecular catalytic Mannich-type reaction is reported.  相似文献   
3.
Evolution process can be calculated from the relativistic hydrodynamic equation with certain estimated initial conditions about a single spherical fireball here.So one can estimate a kind of initial condition qualitatively with a possible energy density about ε0≈1.9 GeV/fm^3,and to fit the experimental data at thermal freeze-out based on this process.The evolution from a cylindrical fireball is discussed simply.  相似文献   
4.
Tetraquarks can be produced in relativistic heavy-ion collision. The yield of this kind of tetraquarks can increase significantly soon as the formation of QGP after the collision. If there is no phase transition after collision, the upper bound of the production of this four-quark states can be estimated from the free hadronlc gas model for nuclear matter. The relative yield ratio of tetraquark cs^-s^-s to Ω is less than 0.0164.  相似文献   
5.
Abstract

Asymmetric Michael-type Friedel–Crafts (F–C) alkylations of indoles with nitroolefins catalyzed by a chiral H8-BINOL-based phosphoric acid were investigated. The reactions took place very smoothly in the presence of only 5 mol-% of catalyst at room temperature to afford the desired F–C alkylation products in good yields and with moderate enantioselectivities.

GRAPHICAL ABSTRACT   相似文献   
6.
Tetraquarks can be produced in relativistic heavy-ion collision. The yield of this kind of tetraquarks can increase significantly soon as the formation of QGP after the collision. If there is no phase transition after collision, the upper bound of the production of this four-quark states can be estimated from the free hadronic gas model for nuclearmatter. The relative yield ratio of tetraquark cs(s)(s) to Ω is less than 0.0164.  相似文献   
7.
Energy density for the central region in relativistic heavy ion collisionscan be estimated via the pseudora-pidity distribution of transverse energy. The way to estimate the local energy density for the centralregion in relativisticheavyion collisions is proposed, in which only final state particles emitted from the same source are included. Thcarrived energy density in NA49 experiments is about 1.03 GeV/fm3.  相似文献   
8.
A way to calculate ratios of baryon produced from quark gluon plasma in relativistic heavyion collisionsis presented. It is assumed that at the beginning of the hadronization there are diquarks and anti-diquarks in the quarkmatter. The number of three-quark states is distributed between the corresponding multiplets, and hadronic decays aretaken into account. The results are shown at last.  相似文献   
9.
Evolution process can be calculated from the relativistic hydrodynamic equation with certain estimatedinitial conditions about a single spherical fireball here. So one can estimate a kind of initial condition qualitatively witha possible energy density about ε0 ≈ 1.9 GeV/fm3, and to fit the experimental data at thermal freeze-out based on thisprocess. The evolution from a cylindrical fireball is discussed simply.  相似文献   
10.
We present a way to calculate tetraquarks ratios for quark gluon plasma with diquarks, The ratios of tetraquarks over baryons produced from quark matter are high than hadronic gas model limits. It is a better way to search for four-quark states in relativistic heavy ion collisions. It may become a criterion to judge whether quark-gluon plasma has formed to search for four-quark states in relativistic heavy ion collisions.  相似文献   
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