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1.
Two-dimensional surface-enhanced Raman scattering(SERS) substrates have drawn intense attention due to their excellent spectral reproducibility, high uniformity and perfect anti-interference ability. However, the inferior detection sensitivity and low enhancement have limited the practical application of two-dimensional SERS substrates. To address this issue, we propose that the interaction between the MoTe_2 substrate and the analyte rhodamine 6 G molecules could be remarkably enhanced by the introduced p-doping effect and lattice distortion of MoTe_2 via hydrogen plasma treatment. After the treatment, the SERS is greatly improved, the enhancement factor of probe molecules reaches 1.83 × 10~6 as well as the limit of detection concentration reaches 10-13 M.This method is anticipated to afford new enhancement probability for other 2D materials, even non-metal oxide semiconductor SERS substrates.  相似文献   
2.

Quantum entanglement is one of the key methods in quantum information processing, but it is difficult to prepare quantum entanglement. Quantum walk is widely used in quantum computation and quantum simulation, it can be applied to the preparation of quantum entangled states. In this paper, a controllable quantum network coding scheme based on quantum walk is proposed. With the help of quantum walk, the scheme preliminary realized the entanglement distribution of butterfly network, reduced entanglement resources and enhanced scalability. According to the existing technology, it is feasible to implement the quantum network coding scheme proposed in this paper.

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3.
We propose a model to describe the energy structure and dynamics of a system of a molecule interacting with infinite photon modes in a vibrating microcavity whose boundary oscillates in the fundamental resonance.By constructing an so(2,1) Lie algebra for the infinite photon modes,we obtain analytical expressions of the energy eigenstates,energy eigenvalues and the system‘s evolution operator for this Raman model under certain conditions.  相似文献   
4.
用中和法合成了氨基酸离子液体1-乙基-3-甲基咪唑丙氨酸([C2mim][Ala]),并利用恒温环境的溶解反应热量计,在(288.15±0.01) K-(308.15±0.01) K温度范围内每隔5 K,测定不同质量摩尔浓度离子液体在水中的溶解焓(ΔsolHmθ).根据Archer的方法,通过线性拟合得到了该离子液体的标准摩尔溶解焓(Δsol),并计算了其相对表观摩尔溶解焓(ΦL).在298.15 K下,根据Glasser经验方法得到了格子能UPOT = 566 kJ·mol-1,并计算了其阴阳离子水化焓值(ΔH+ + ΔH-) = -620 kJ·mol-1及阴离子水化焓ΔH-([Ala]-) = -387 kJ·mol-1.此外,估算了[C2mim][Ala]水溶液的热容(Cp(sol))和表观摩尔热容(ΦCp).  相似文献   
5.
We present the explicit analytical expressions of the steady-state probability amplitudes and populations of atom levels in N-photon electromagnetically induced transparency for an arbitrary positive integer N.  相似文献   
6.
建立了超声酸提取-高效液相-原子荧光联用测定温州海产品中无机汞[Hg(Ⅱ)]、甲基汞(MeHg)和乙基汞(EtHg)含量的方法,并优化了实验条件.实验采用5mol/L盐酸溶液,超声3.0h提取汞化合物,硫代硫酸钠络合,最后经C18柱(4.6mm×150mm)分离,流动相为5%乙腈-0.06mol/L乙酸铵-0.12% L-半胱氨酸.在最佳条件下,3种汞化合物在0-20μg/L范围内线性良好,相关系数(r)均优于0.9990,检出限分别为1.04、1.09和1.29μμg/L,相对标准偏差(RSDs)均小于5%(n=10),温州海产品的汞加标回收率达到90.1%-107.3%.该方法操作简便,精密度高,干扰少,适用于各地海产品中汞化合物的形态分析测定.  相似文献   
7.
A photoinduced flexible Li-CO2 battery with well-designed, hierarchical porous, and free-standing In2S3@CNT/SS (ICS) as a bifunctional photoelectrode to accelerate both the CO2 reduction and evolution reactions (CDRR and CDER) is presented. The photoinduced Li-CO2 battery achieved a record-high discharge voltage of 3.14 V, surpassing the thermodynamic limit of 2.80 V, and an ultra-low charge voltage of 3.20 V, achieving a round trip efficiency of 98.1 %, which is the highest value ever reported (<80 %) so far. These excellent properties can be ascribed to the hierarchical porous and free-standing structure of ICS, as well as the key role of photogenerated electrons and holes during discharging and charging processes. A mechanism is proposed for pre-activating CO2 by reducing In3+ to In+ under light illumination. The mechanism of the bifunctional light-assisted process provides insight into photoinduced Li-CO2 batteries and contributes to resolving the major setbacks of the system.  相似文献   
8.
Six new O-alkyldithiophosphate nickel complexes with dcpf ligand, [(dcpf)Ni(S2P{O}OR)] (dcpf = 1,1′-bis (dicyclohexylphosphino)ferrocene, R = CH3 ( 1 ), CH3CH2 ( 2 ), Ph ( 3 ), 4-MeC6H4 ( 4 ), PhCH2 ( 5 ) and PhCH2CH2 ( 6 )), have been synthesized by the treatment of dcpf with ((RO)2PS2)2Ni in satisfactory yields. These complexes were characterized by elemental analysis, spectroscopy (FTIR, UV–vis, 1H, 13C, and 31P NMR), thermogravimetric analysis and single crystal X-ray diffraction. The nickel atom in 1 , 2 ·CH2Cl2, 3 ·CH2Cl2, 4 ·2CH2Cl2·THF, and 2( 5 )·hexane adopts a slightly distorted square-planar coordination environment finished by two phosphorus atoms of dcpf ligand and two sulfur atoms of O-alkyldithiophosphate ligand. Furthermore, the electrochemical properties for complexes 1 – 6 were also investigated by cyclic voltammetry. With the addition of 120 mM trifluoroacetic acid (TFA), the turnover frequency (TOF) values for 1 – 6 are estimated to be 1243.83, 1046.54, 1331.71, 2545.29, 1899.03, and 1191.37 s−1, with the overpotential (η) values of 0.62, 0.58, 0.71, 0.67, 0.60, and 0.56 V, respectively. The result of electrochemical studies indicates that all complexes can be used as efficient molecular eletrocatalysts for the reduction of protons to hydrogen in the presence of TFA in MeCN.  相似文献   
9.
制备了吡啶类离子液体N-己基吡啶二氰胺盐[C_6py][DCA],并用核磁共振氢谱(~1H NMR)、核磁共振碳谱(~(13)C NMR)、差热扫描量热(DSC)、傅里叶变换红外(FT-IR)光谱对其进行表征。在288.15–338.15 K温度范围内,采用标准加入法,测定其密度(ρ)、表面张力(γ)和折光率(n_D)。在测得的实验数据的基础上,得到了离子液体[C_6py][DCA]的分子体积(V_m)、表面能(E_a)、摩尔极化度(R_m)和极化率(α_p)。结果显示E_a、R_m和α_p几乎不随温度的变化而发生改变。本文还提出了摩尔表面Gibbs自由能(g_s)的概念,并改进了E?tv?s方程。同时还计算了gs、临界温度(T_c)和E?tv?s方程经验参数(kE),并预测了离子液体[C_6py][DCA]的表面张力,预测值与实验值具有较好的一致性。  相似文献   
10.
A series of two-dimensional equations with the two-dimensional Korteweg-de Vries equation being their first one are constructed as Sawada-Kotera did in one-dimensional case. Their soliton chain solutions are obtained and investigated.  相似文献   
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