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51.
Liangzhao Cai Mengyao Xue Jia Lun Shuang Li Jia Yu Xingjie Guo 《Electrophoresis》2020,41(24):2092-2101
The enantioseparation of eight psychoactive drugs has been firstly performed on a coated cellulose-based chiral stationary phase (Chiralcel OJ-H). To obtain optimum separation conditions, the influences of alcohol modifiers and basic/acidic additives have been studied. As a result, except for the partial separation of oxybutynin enantiomers, the other seven drug enantiomers, including mirtazapine, sulpiride, promethazine, citalopram, oxazepam, donepezil, and cyamemazine, have been completely separated. Additionally, for gaining a better insight into the chiral recognition mechanisms, molecular docking was carried out using the Autodock software. Herein, binding energy and conformations of the chiral stationary phase complexes were provided, and it was found that the distinction in enantiomeric conformation determined the number and strength of intermolecular interactions between analytes and chiral stationary phase which resulted in the difference in binding energies of two enantiomers, and ultimately led to the different migration. These modeling results were in accordance with the observed enantioseparation results in high performance liquid chromatography experiments. At last, chiral separation mechanisms have been discussed in detail, and it has been confirmed that hydrogen bond, π–π, hydrophobic interactions, and some special interactions synergistically contributed to the enantioseparation of psychoactive drugs. 相似文献
52.
Yiliang Wang Liu-Pan Yang Xiang Zhao Lei Cui Jian Li Xueshun Jia Jianhui Fang Chunju Li 《Molecules (Basel, Switzerland)》2020,25(24)
Conformational exchanges of synthetic macrocyclic acceptors are rather fast, which is rarely studied in the absence of guests. Here, we report multiple stimuli-responsive conformational exchanges between two preexisting conformations of 2,2′,4,4′-tetramethoxyl biphen[3]arene (MeBP3) macrocycle. Structures of these two conformations are both observed in solid state, and characterized by 1H NMR, 13C NMR and 2D NMR in solution. In particular, conformational exchanges can respond to solvents, temperatures, guest binding and acid/base addition. The current system may have a role to play in the construction of molecular switches and other stimuli-responsive systems. 相似文献
53.
Nonlinear Dynamics - Chaotic resonance (CR) is the response of a nonlinear system to weak signals enhanced by internal or external chaotic activity (such as the signal derived from Lorenz system).... 相似文献
54.
Feng Zhanxia Chang Zongyu Deng Chao Zhao Lin Chen Jia Zhang Jiakun Zheng Zhongqiang 《Nonlinear dynamics》2022,108(3):2007-2022
Nonlinear Dynamics - Wave glider is an unmanned surface vehicle that can directly convert wave energy into forward propulsion and fulfill long-term marine monitoring. A previous study suggested... 相似文献
55.
将一种人工合成的无机聚合物——蒙脱石皂石黏土(smectite,Sm)应用于基质辅助激光解吸电离飞行时间质谱分析(matrix-assisted laser desorption/ionization time of flight mass spectrometry, MALDI-TOF-MS),以检测糖类化合物。 将传统的有机基质2,4,6-三羟基苯乙酮(trihydroxyacetophenone, THAP)与阳离子交换后的皂石黏土混合制备成新型复合基质,应用于糖类化合物的检测。通过比较不同的制样方法,测定不同分子直径的糖类化合物,发现由于受复合基质晶面间距的限制,只有小分子糖类化合物能进入晶面间隙充分接触有机基质并被离子化,从而实现对小分子糖类化合物的选择性检测。 相似文献
56.
Jia Zhao 《应用数学与计算数学学报》2021,(2):357-369
In this paper,we introduce a new deep learning framework for discovering the phase-field models from existing image data.The new framework embraces the approxim... 相似文献
57.
58.
The three lowest-lying states, i.e., (1S), (2S), and (3S), composed of bb¯ pairs and below the BB ¯ threshold, provide a good platform for the researches of hadronic physics and physics beyond the Standard Model. They can be produced directly in e+e− colliding experiments, such as CLEO, Babar, and Belle, with low continuum backgrounds. In these experiments, many measurements of the exclusive (1S) and (2S) decays into light hadrons, which shed light on the “80% rule” for the Okubo–Zweig–Iizuka suppressed decays in the bottomonium sector, were carried out. Meanwhile, many studies of the charmonium and bottomonium productions in (1S, 2S, 3S) decays were performed, to distinguish different Quantum Chromodynamics (QCD) models. Besides, exotic states and new physics were also extensively explored in (1S, 2S, 3S) decays at CLEO, BaBar, and Belle. The (1S, 2S, 3S) states can also be produced in pp collisions and in collisions involving heavy ions. The precision measurements of their cross sections and polarizations at the large hadron collider (LHC), especially in the CMS, ATLAS, and LHCb experiments, help to understandΥproduction mechanisms in pp collisions. The observation of the sequentialΥsuppression in heavy ion collisions at CMS, LHCb, and ALICE is of great importance for verifying the quark–gluon plasma predicted by QCD. In this article, we review the experimental results on (1S, 2S, 3S) at e+e− colliders and the LHC, and summarize their prospects at Belle II and the LHC. 相似文献
59.
Bismuth oxide subacetate(CH3COO(BiO);BiOAc)with a large band gap energy(Eg)was first applied as an ultraviolet-light-driven photocatalyst in our group.MoS2 nano... 相似文献
60.
Lei Jia Jianzhu Wang Tianyuan Wang Xiaobao Li Haomin Yu Qingyong Li 《Entropy (Basel, Switzerland)》2022,24(4)
Vehicles carrying hazardous material (hazmat) are severe threats to the safety of highway transportation, and a model that can automatically recognize hazmat markers installed or attached on vehicles is essential for intelligent management systems. However, there is still no public dataset for benchmarking the task of hazmat marker detection. To this end, this paper releases a large-scale vehicle hazmat marker dataset named VisInt-VHM, which includes 10,000 images with a total of 20,023 hazmat markers captured under different environmental conditions from a real-world highway. Meanwhile, we provide an compact hazmat marker detection network named HMD-Net, which utilizes a revised lightweight backbone and is further compressed by channel pruning. As a consequence, the trained-model can be efficiently deployed on a resource-restricted edge device. Experimental results demonstrate that compared with some established methods such as YOLOv3, YOLOv4, their lightweight versions and popular lightweight models, HMD-Net can achieve a better trade-off between the detection accuracy and the inference speed. 相似文献