Vortex lattices in a spin-orbit coupled binary Bose-Einstein condensates with dipolar interaction

International Journal of Theoretical Physics - We consider the stationary state of a spin-orbit coupled (SOC) binary Bose-Einstein condensates with dipole-dipole interaction (DDI). Our results are...     

基于模糊神经元PID算法的注塑机注射速度控制算法研究

基于一款市场较为畅销的注塑机, 设计出一种能精确控制注射速度的模糊神经元PID控制器. 首先, 设计出具有自学能力的神经元PID控制器, 利用模糊算法对其进行优化; 其次, 在原有注射速度线性数学模型的基础上, 构建注塑机注射速度的非线性模型; 最后, 利用MATLAB在所建数学模型的基础上对模糊神经元PID控制器进行仿真实验. 实验结果表明, 所设计控制器具有响应迅速、无超调量、控制精度高、控制稳定等优点.     

Direct gem-Difluoroalkenylation of X−H Bonds with Trifluoromethyl Ketone N-Triftosylhydrazones for Synthesis of Tetrasubstituted Heteroatomic gem-Difluoroalkenes

The direct gem-difluoroalkenylation of X−H bonds represents the most straightforward approach to access heteroatomic gem-difluoroalkenes that, as the isostere of the carbonyl group, have great potency in drug discovery. However, the construction of tetrasubstituted heteroatomic gem-difluoroalkenes by this strategy is still an unsolved problem. Here, we report the first direct X−H bond gem-difluoroalkenylation of amines and alcohols with trifluoromethyl ketone N-triftosylhydrazones under silver (for (hetero)aryl hydrazones) or rhodium (for alkyl hydrazones), thereby providing a most powerful method for the synthesis of tetrasubstituted heteroatomic gem-difluoroalkenes. This method features a broad substrate scope, high product yield, excellent functional group tolerance, and operational simplicity (open air conditions). Moreover, the site-specific replacement of the carbonyl group with a gem-difluorovinyl ether bioisostere in drug Trimebutine and the post-modification of bioactive molecules demonstrates potential use in medicinal research. Finally, the reaction mechanism was investigated by combining experiments and DFT calculations, and disclosed that the key step of HF elimination occurred via five-membered ring transition state, and the difference in the electrophilicity of Ag- and Rh-carbenes as well as the multiple intermolecular interactions rendered the effectiveness of Rh catalyst selectively for alkyl hydrazones.     

Raman Scattering Enhancement Based on High-Pressure High-Temperature Diamonds†

Journal of Russian Laser Research - We discuss the use of high-pressure high-temperature (HPHT) diamonds for the determination of trace amounts of various Raman active substances. The amount of the...     

Concentrated steady vorticities of the Euler equation on 2-d domains and their linear stability

We consider concentrated vorticities for the Euler equation on a smooth domain $\mathrm{\Omega }?{\mathbf{R}}^2$ in the form of

$\omega =\sum _{j=1}^N{\omega }_j{\chi }_{{\mathrm{\Omega }}_j},|{\mathrm{\Omega }}_j|=\pi r_j^2,\underset{{\mathrm{\Omega }}_j}{\int }{\omega }_{j}d\mu ={\mu }_j\ne 0,$

supported on well-separated vortical domains ${\mathrm{\Omega }}_j$, $j=1,\dots ,N$, of small diameters $O(r_j)$. A conformal mapping framework is set up to study this free boundary problem with ${\mathrm{\Omega }}_j$ being part of unknowns. For any given vorticities ${\mu }_1,\dots ,{\mu }_N$ and small $r_1,\dots ,r_N\in {\mathbf{R}}^{+}$, through a perturbation approach, we obtain such piecewise constant steady vortex patches as well as piecewise smooth Lipschitz steady vorticities, both concentrated near non-degenerate critical configurations of the Kirchhoff–Routh Hamiltonian function. When vortex patch evolution is considered as the boundary dynamics of $?{\mathrm{\Omega }}_j$, through an invariant subspace decomposition, it is also proved that the spectral/linear stability of such steady vortex patches is largely determined by that of the 2N-dimensional linearized point vortex dynamics, while the motion is highly oscillatory in the 2N-codim directions corresponding to the vortical domain shapes.     

Two novel Co (II)-coordination polymers as bifunctional materials for efficient photocatalytic degradation of dyes and electrocatalytic water oxidation

Two novel Co (II)- coordination polymers (CPs) based on 2,5-bis(4-carboxylpheny)-1,3,4-oxadiazole (bcpo), namely [Co/(bcpo)_0.5(tib)(H₂O)₂]_n (1) and [Co (bcpo)_0.5(bidpe)(H₂O)₂]_n (2) (tib = 1,3,5-tirs(1-imidazolyl)benzene, bidpe = 4,4′-bis (imidazolyl)diphenyl ether) have been synthesized under solvothermal conditions and characterized by powder X-ray diffraction (PXRD), single crystal X-ray diffraction, photochemistry as well as electrochemistry. The investigation of the photo-degradation methyl blue and methyl violet (MB, MV) properties of CPs 1–2 demonstrates that CP 1 shows great performance for the degradation of MB, and CP 2 could efficiently degrade MB/MV. Meanwhile, the possible photo-degradation mechanism has been proposed and explored. Simultaneously, electrochemistry studies show that both CPs 1 and 2 can catalyze water oxidation under an alkaline condition at the potential around 1.20 V vs. NHE with relatively low overpotential of 330–510 mV vs. NHE.