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961.
The swimming mode of two interacting squirmers under gravity in a narrow vertical channel is simulated numerically using the lattice Boltzmann method (LBM) in the range of self-propelling strength 0.1 ≤ α ≤ 1.1 and swimming type −5 ≤ β ≤ 5. The results showed that there exist five typical swimming patterns for individual squirmers, i.e., steady upward rising (SUR), oscillation across the channel (OAC), oscillation near the wall (ONW), steady upward rising with small-amplitude oscillation (SURO), and vertical motion along the sidewall (VMS). The parametric space (α, β) illustrated the interactions on each pattern. In particular, the range of oscillation angle for ONW is from 19.8° to 32.4° as α varies from 0.3 to 0.7. Moreover, the swimming modes of two interacting squirmers combine the two squirmers’ independent swimming patterns. On the other hand, the pullers (β < 0) attract with each other at the initial stage, resulting in a low-pressure region between them and making the two pullers gradually move closer and finally make contact, while the result for the pushers (β > 0) is the opposite. After the squirmers’ interaction, the squirmer orientation and pressure distribution determine subsequent squirmer swimming patterns. Two pushers separate quickly, while there will be a more extended interaction period before the two pullers are entirely separated. 相似文献
962.
Mengzi Nie Chunhong Piao Jiaxin Li Yue He Huihan Xi Zhiying Chen Lili Wang Liya Liu Yatao Huang Fengzhong Wang Litao Tong 《Molecules (Basel, Switzerland)》2022,27(19)
The purpose of this study was to compare the gelatinization and retrogradation properties of highland barley starch (HBS) using different extraction methods. We obtained HBS by three methods, including alkali extraction (A-HBS), ultrasound extraction (U-HBS) and enzyme extraction (E-HBS). An investigation was carried out using a rapid viscosity analyzer (RVA), texture profile analysis (TPA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and Fourier-transform infrared spectrometry (FTIR). It is shown that the different extraction methods did not change the crystalline type of HBS. E-HBS had the lowest damaged starch content and highest relative crystallinity value (p < 0.05). Meanwhile, A-HBS had the highest peak viscosity, indicating the best water absorption (p < 0.05). Moreover, E-HBS had not only higher G′ and G″ values, but also the highest gel hardness value, reflecting its strong gel structure (p < 0.05). These results confirmed that E-HBS provided better pasting stability and rheological properties, while U-HBS provides benefits of reducing starch retrogradation. 相似文献
963.
The direct hydroxylation of benzene is a green and economical-efficient alternative to the existing cumene process for phenol production. However, the undesired phenol selectivity at high benzene conversion hinders its wide application. Here, we develop a one-pot synthesis of protonated g-C3N4 supporting vanadia catalysts (V-pg-C3N4) for the efficient and selective hydroxylation of benzene. Characterizations suggest that protonating g-C3N4 in diluted HCl can boost the generation of amino groups (NH/NH2) without changing the bulk structure. The content of surface amino groups, which determines the dispersion of vanadia, can be easily regulated by the amount of HCl added in the preparation. Increasing the content of surface amino groups benefits the dispersion of vanadia, which eventually leads to improved H2O2 activation and benzene hydroxylation. The optimal catalyst, V-pg-C3N4-0.46, achieves 60% benzene conversion and 99.7% phenol selectivity at 60 oC with H2O2 as the oxidant. 相似文献
964.
Xufeng Nie Yachuan Wang Lijun Yang Zaijun Yang Tairan Kang 《Tetrahedron letters》2017,58(31):3003-3007
A metal-free cyclopropanation of electron-deficient olefins 3-substituted-2-cyanoacrylamides with N-tosylhydrazones has been successfully developed. This strategy provide a simple route to the synthesis of very valuable 1-cyanocyclopropanecarboxamides with a quaternary stereogenic center in good yields and with high diastereoselectivities (up to 90% yield with 19:1 dr). The reaction could be performed in one-pot fashion and in a gram-scale from aryl aldehydes. 相似文献
965.
966.
967.
Jing Nie Xiuyi Yang Qing-Xu Yu Chong Li 《International Journal of Theoretical Physics》2014,53(12):4291-4301
We have studied the non-Markovian decoherence dynamics of the two-level system in a composite environment, which consists of a spin-star environment and a boson reservoir. By use of the measures presented recently, we theoretically study the non-Markovianity of the dynamics of the model. 相似文献
968.
Yuan-hua Li Ming-huang Sang Yi-you Nie 《International Journal of Theoretical Physics》2016,55(11):4693-4698
An experimental protocol for preparing an eight-qubit entangled state in cavity QED is proposed, which is insensitive to the cavity decay and the thermal field. And the experimental feasibility of our protocol is discussed. 相似文献
969.
Selective transformation of carbohydrates to hydroxymethyl furfural with polyaniline-based catalysts
Nie Guangxia Tong Xinli Zhang Yangyang Liang Mao Zhuang Xuli Xue Song 《Research on Chemical Intermediates》2016,42(12):8305-8319
Research on Chemical Intermediates - The efficient production of 5-hydroxymethyl furfural (HMF) from carbohydrates is achieved in the presence of polyaniline-based solid catalysts. The composite... 相似文献
970.