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排序方式: 共有718条查询结果,搜索用时 15 毫秒
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Ze-Fang Jiang Shanshan Cao Wen-Jing Xing Xiaowen Li Ben-Wei Zhang 《中国物理C(英文版)》2023,47(2):024107-024107-9
Heavy quark observables are applied to probe the initial energy density distribution with violation of longitudinal boost invariance produced in relativistic heavy-ion collisions. Using an improved Langevin model coupled to a (3+1)-dimensional viscous hydrodynamic model, we study the nuclear modification factor (\begin{document}$R_{AA}$\end{document} ![]()
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) and directed flow (\begin{document}$ v_1 $\end{document} ![]()
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) and elliptic flow (\begin{document}$ v_2 $\end{document} ![]()
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) coefficients of heavy mesons and their decayed electrons at an RHIC energy. We find that the counter-clockwise tilt of nuclear matter in the reaction plane results in a positive (negative) heavy flavor \begin{document}$ v_1 $\end{document} ![]()
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in the backward (forward) rapidity region, whose magnitude increases with the heavy quark transverse momentum. The difference in the heavy flavor \begin{document}$R_{AA}$\end{document} ![]()
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between different angular regions is also proposed as a complementary tool to characterize the asymmetry of the medium profile. Our model results are consistent with currently available data at the RHIC and provide predictions that can be tested by future measurements. 相似文献
714.
Prof. Dr. Wei Zuo Yu Tao Zhipeng Luo Prof. Dr. Anyang Li Shanshan Wang Xinrui Qiao Prof. Dr. Fen Ma Prof. Dr. Chuandong Jia 《Angewandte Chemie (International ed. in English)》2023,62(12):e202300470
Inspired by the signal transduction function of organophosphates in biological systems, bioactive organophosphates were utilized for the first time as chiral nodes to dictate the stereoselective assembly of hydrogen-bonded anionic cages. Phosphonomycin (antibiotics), tenofovir (antivirals), adenosine monophosphate (natural product, AMP) and clindamycin phosphate (antibiotics) were assembled with an achiral bis-monourea ligand, thereby leading to the stereoselective formation of quadruple or triple helicates. The extent of the stereoselectivity could be enhanced by either lowering the temperature or adding stronger-binding cations as templates. With the chiral anionic cages as the host, some enantioselectivity was achieved when binding chiral quaternary ammonium cations. 相似文献
715.
Hugo Amistadi-Revol Shanshan Liu Dr. Sébastien Prévost 《European journal of organic chemistry》2023,26(31):e202300582
In order to directly functionalize C−H bonds of complex molecules and, in particular, to control the regioselectivity of the reaction, a wide range of directing groups has been used. However, these directing groups need to be installed and removed for further applications, which may limit the use of C−H activation in synthesis. Concerning aldehydes and ketones, a transient directing group strategy has recently emerged to overcome this drawback. The addition of an additive, in general an amine, allowed the in situ formation of the real directing group to achieve C−H activation. This review presents the latest developments in the field over the period 2020–2023. 相似文献
716.
Shanshan Li Xiaotian Wu Yuxin Ke Prof. Dr. Chen Ma 《European journal of organic chemistry》2023,26(15):e202201473
We have developed a useful method to synthesize quinoline derivatives, which required no transition metals, no peroxides, and no high temperatures. This method provides a novel and gentle synthetic route for various multifunctional 2,4-diarylquinolines with good yields. 相似文献
717.
This paper is concerned with the number of limit cycles for a class of piecewise Hamiltonian systems with two zones separated by two semi-straight lines. By constructing a Poincar\''{e} map, we obtain explicit expressions of the first, second and third order Melnikov functions. In addition, we apply their expressions to give upper bounds of the number of limit cycles bifurcated from
a period annulus of a piecewise polynomial Hamiltonian system. 相似文献
718.