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61.
The single-photon excitation and transmission spectra of strong-coupling hybrid optomechanics are theoretically analyzed, where a two-level system (TLS) is coupled to a mechanical resonator (MR), generating Jaynes–Cummings-type polariton doublets. In this model, both the optomechanical coupling and the TLS-MR coupling are strong. In this parameter region, polaron-assisted excitation reemission processes can strongly affect the single-photon excitation and output spectra of the cavity. It is found that the fine structure around each sideband can be used to characterize the TLS-MR and the effective TLS-photon couplings, even at the single-quantum level. Thus, the spectrum structures may make it possible to sensitively probe the quantum nature of a macroscopic mechanical element. A possible approach for tomographic reconstruction of the state of a TLS, utilizing the single-photon transmission spectra, is further provided. 相似文献
62.
ABSTRACTThe complexes of H2X (X?=?O, S, Se) with hypervalent halogens YF3 and YF5 (Y?=?Cl, Br, I) have been studied. The σ-hole on the Y atom participates in a halogen bond with the lone pair on the chalcogen atom. In addition, some secondary interactions coexist with the halogen bond in most complexes. The interaction energy correlates with the nature of both X and Y atoms. In most cases, the complex is more stable for the heavier Y atom and the lighter X atom. Of course, there are some exceptions in H2X···YF3. YF3 forms a more stable complex with H2X than does YF5. These complexes are dominated by electrostatic interaction and the halogen bond involving H2S and H2Se exhibits some covalent character.Halogen bond plays an important role in chemical reactions and multivalent halogens can regulate chemical reactions by participating in a halogen bond. Thus we compare the effect of the chalcogen electron donor on the strength and nature of halogen bonding involving multivalent halogens. 相似文献
63.
Sudipta Ponra Jianping Yang Haibo Wu Wangchuk Rabten Pher G. Andersson 《Chemical science》2020,11(41):11189
We have developed a simple protocol for the preparation of 1,2-fluorohydrin by asymmetric hydrogenation of fluorinated allylic alcohols using an efficient azabicyclo thiazole-phosphine iridium complex. The iridium-catalyzed asymmetric synthesis of chiral 1,2-fluorohydrin molecules was carried out at ambient temperature with operational simplicity, and scalability. This method was compatible with various aromatic, aliphatic, and heterocyclic fluorinated compounds as well as a variety of polyfluorinated compounds, providing the corresponding products in excellent yields and enantioselectivities.We have developed a simple protocol for the preparation of 1,2-fluorohydrin by asymmetric hydrogenation of fluorinated allylic alcohols using an efficient azabicyclo thiazole-phosphine iridium complex. 相似文献
64.
Let x=(x',x')with x'∈Rk and x'∈R^N-k andΩbe a x'-symmetric and bounded domain in R^N(N≥2).We show that if 0≤a≤k-2,then there exists a positive constant C>0 such that for all x'-symmetric function u∈C0^∞(Ω)with∫Ω|■u(x)|^N-a|x'|^-adx≤1,the following uniform inequality holds1/∫Ω|x|^-adx∫Ωe^βa|u|N-a/N-a-1|x'|^-adx≤C,whereβa=(N-a)(2πN/2Γ(k-a/2)Γ(k/2)/Γ(k/2)r(N-a/2))1/N-a-1.Furthermore,βa can not be replaced by any greater number.As the application,we obtain some weighted Trudinger–Moser inequalities for x-symmetric function on Grushin space. 相似文献
65.
Cen Benqiang Li Kexun Lv Cuicui Yang Rui 《Journal of Solid State Electrochemistry》2020,24(3):687-697
Journal of Solid State Electrochemistry - In this work, we synthesized metal-organic framework Cu3(BTC)2 which was applied as the doping materials of anode electrodes in capacitive deionization... 相似文献
66.
Jialong Duan Yudi Wang Xiya Yang Qunwei Tang 《Angewandte Chemie (International ed. in English)》2020,59(11):4391-4395
Improved charge extraction and wide spectral absorption promote power conversion efficiency of perovskite solar cells (PSCs). The state‐of‐the‐art carbon‐based CsPbBr3 PSCs have an inferior power output capacity because of the large optical band gap of the perovskite film and the high energy barrier at perovskite/carbon interface. Herein, we use alkyl‐chain regulated quantum dots as hole‐conductors to reduce charge recombination. By precisely controlling alkyl‐chain length of ligands, a balance between the surface dipole induced charge coulomb repulsive force and quantum tunneling distance is achieved to maximize charge extraction. A fluorescent carbon electrode is used as a cathode to harvest the unabsorbed incident light and to emit fluorescent light at 516 nm for re‐absorption by the perovskite film. The optimized PSC free of encapsulation achieves a maximum power conversion efficiency up to 10.85 % with nearly unchanged photovoltaic performances under 80 %RH, 80 °C, or light irradiation in air. 相似文献
67.
Numerical Algorithms - This paper considers the inverse problem for identifying the initial value problem of a space-time fractional diffusion wave equation. In general, this problem is ill-posed... 相似文献
68.
QiuHong Wang Abdusalam Abdukerim Wei Chen Xun Chen YunHua Chen XiangYi Cui YingJie Fan DeQing Fang ChangBo Fu LiSheng Geng Karl Giboni Franco Giuliani LinHui Gu XuYuan Guo Ke Han ChangDa He Di Huang Yan Huang YanLin Huang Zhou Huang Peng Ji XiangDong Ji YongLin Ju YiHui Lai Kun Liang HuaXuan Liu JiangLai Liu WenBo Ma YuGang Ma YaJun Mao Yue Meng Parinya Namwongsa KaiXiang Ni JinHua Ning XuYang Ning XiangXiang Ren ChangSong Shang Lin Si AnDi Tan AnQing Wang HongWei Wang Meng Wang SiGuang Wang XiuLi Wang Zhou Wang MengMeng Wu ShiYong Wu JingKai Xia MengJiao Xiao PengWei Xie BinBin Yan JiJun Yang Yong Yang ChunXu Yu Jumin Yuan Dan Zhang HongGuang Zhang Tao Zhang Li Zhao QiBin Zheng JiFang Zhou Ning Zhou XiaoPeng Zhou 《中国科学:物理学 力学 天文学(英文版)》2020,(3):54-63
In dark matter direct detection experiments,neutron is a serious source of background,which can mimic the dark matter-nucleus scattering signals.In this paper,we present an improved evaluation of the neutron background in the PandaX-II dark matter experiment by a novel approach.Instead of fully relying on the Monte Carlo simulation,the overall neutron background is determined from the neutron-induced high energy signals in the data.In addition,the probability of producing a dark-matter-like background per neutron is evaluated with a complete Monte Carlo generator,where the correlated emission of neutron(s)andγ(s)in the(α,n)reactions and spontaneous fissions is taken into consideration.With this method,the neutron backgrounds in the Run 9(26-ton-day)and Run 10(28-ton-day)data sets of PandaX-II are estimated to be(0.66±0.24)and(0.47±0.25)events,respectively. 相似文献
69.
Nonlinear Dynamics - Global dynamics of a flexible asymmetrical rotor resting on vibrating supports is investigated. Hamilton’s principle is used to derive the partial differential governing... 相似文献
70.
Ge Huang Prof. Li Yang Qi Yin Zhi-Bin Fang Xiao-Jing Hu An-An Zhang Prof. Jun Jiang Prof. Tian-Fu Liu Prof. Rong Cao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(11):4415-4420
Although many ionic metal–organic frameworks (MOFs) have been reported, little is known about how the charge of the skeleton affects the properties of the MOF materials. Herein we report how the chemical stability of MOFs can be substantially improved through embedding electrostatic interactions in structure. A MOF with a cationic skeleton is impervious to extremely acidic, oxidative, reductive, and high ionic strength conditions, such as 12 m HCl (301 days), aqua regia (86 days), H2O2 (30 days), and seawater (30 days), which is unprecedented for MOFs. DFT calculations suggested that steric hinderance and the repulsive interaction of the cationic framework toward positively charged species in microenvironments protects the vulnerable bonds in the structure. Diverse functionalities can be bestowed by substituting the counterions of the charged framework with identically charged functional species, which broadens the horizon in the design of MOFs adaptable to a demanding environment with specific functionalities. 相似文献