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61.
62.
通过介绍混合教学模式在有机化学实验课程教学中的设计、实施情况及效果评价与反馈等内容,与大家分享混合教学模式在有机化学实验课程教学中的应用经验与思考。 相似文献
63.
Yu Liu Xian-Hua Li Qiu-Li Li Guo-Qiang Tang 《Surface and interface analysis : SIA》2020,52(5):214-223
A zircon U–Pb dating method with a high spatial resolution of 2- to 3-μm was successfully implemented by using Cameca IMS-1280HR SIMS in this study. Homemade cathode and modified intermediate pole were used to improve the intrinsic performance of duoplasmatron ion source. An O− primary beam with intensity of approximately 3 μA and stability of 0.68% over 40 minutes was achieved and could be used continuously for more than 240 hours under high current conditions. Under Gaussian illumination mode, a 2- to 3-μm O− primary beam was obtained with an intensity of approximately 200 pA. Four standard zircons, namely, 91500, Temora, Plešovice, and Qinghu, were dated using the 2- to 3-μm high spatial resolution U–Pb isotopic analysis, yielding U–Pb ages consistent with their recommended values, within errors. Our work shows that zircon U–Pb dating with high accuracy and spatial resolution can be achieved, on the basis of a series of duoplasmatron modification and instrumental optimization. 相似文献
64.
Yu Chen Cagri Ayranci Tian Tang 《Journal of polymer science. Part A, Polymer chemistry》2022,60(9):1539-1549
Viscoelastic properties of moisture-sensitive polymers can be significantly affected by moisture in the ambient environment, resulting in drastic changes in the properties as the absorbed moisture content increases. In this article, a simple yet important modification to the Reimschuessel model is introduced by considering both plasticization and anti-plasticization induced by water molecules. The proposed model is validated against the results of four different polymers obtained by Onogi et al., which demonstrates its capability of describing the available data. This model can be used to estimate the performance and service life of products produced using moisture-sensitive polymers. It also reveals that small amounts of diffused moisture might have a stiffening effect on the mechanical properties of hydrophilic polymers. 相似文献
65.
Weiquan Xu Jin-Yu Chao Dr. Bohan Tang Prof. Zhan-Ting Li Prof. Jiang-Fei Xu Prof. Xi Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(63):e202202200
A supramolecular organic framework-type photocatalyst, named TM-SOF, is constructed by the self-assembly of cucurbit[8]uril and a tetra-arm monomer containing four N, N’-dimethyl 2,5-bis(4-pyridinium)thiazolo[5,4-d]thiazole (MPT) moieties. Benefiting from the multivalent assembly, a photocatalytically active supramolecular MPT dimer can be stably formed in TM-SOF. In addition, TM-SOF exhibits better stability against temperature, substrate, and light irradiation. As a result, TM-SOF shows a significantly improved performance for the photocatalytic aerobic oxidation of aryl boronic acids and thioethers. It is anticipated that this line of research will provide a facile approach for fabricating high-performance supramolecular photocatalysis systems. 相似文献
66.
Li Mengya Yan Pengfei Liu Jie Pei Ying Zheng Xuejing Tang Keyong Wang Fang 《Cellulose (London, England)》2022,29(3):1609-1621
Cellulose - One-step acid hydrolysis was successfully employed to prepare carboxylated cellulose nanofibrils (CCNFs) from pomelo peel waste with the mixture of hydrochloric acid and citric acid... 相似文献
67.
Ricerche di Matematica - In this paper, we investigate a mixed fractional integral boundary value problem with p(t)-Laplacian operator. Firstly, we derive the Green function through the direct... 相似文献
68.
为了改善高速流动工况下水翼吸力面上流场的空化特性,提出了水翼表面主动射流对绕水翼周围流动加以控制的方法.基于密度分域滤波的FBDCM混合湍流模型联合Zwart-Gerber-Belamri空化模型,分析了来流空化数为0.83,来流攻角为8°,射流位置距水翼前缘为x=0.19c时,主动射流对于水翼吸力面上流动的空化特性和水动力特性影响.对回射流的强度进行了量化分析,以探究回射流与流场空化特性的关系.数值分析结果表明,在射流水翼吸力面上的时均空泡体积为原始水翼的1/15,使得流场内空化流动由云空化状态转变为较为稳定的片空化状态,显著地削弱了云空化的发展.此外,射流极大地改善了水翼的水动力性能,使得水翼的升阻比较原始水翼提高了22.9%,空泡的脱落频率减少了26.2%,空泡脱落所引起的振幅减小了9.1%.射流大幅降低了水翼吸力面上低压区面积,水翼吸力面上流体的逆向压力减小,回射流强度降低;同时,射流使水翼吸力面上的边界层减薄,增强了流动的抗逆压梯度能力,一定程度上阻挡了回射流向水翼前缘的流动,这也从机理上分析了主动射流抑制空化的原因. 相似文献
69.
Nonlinear Dynamics - A finite element model of the cantilever combined support rotor included two discs established in this paper to predict and explain the nonlinear vibration phenomenon. The... 相似文献
70.
Jian-Kun Sun Linlin Zhang Liang Yue Tang Tang Wen-Jie Jiang Yun Zhang Zhenxiao Pan Xinhua Zhong Jin-Song Hu Li-Jun Wan 《中国科学:化学(英文版)》2018,61(10):1338-1344
Developing efficient counter electrodes (CEs) and quantum dots made of earth-abundant and non-toxic elements is essential but still challenging for quantum dot-sensitized solar cells (QDSSCs). Here, we report a facile strategy to prepare self-supported and robust CoS2 and NiS nanocrystals-assembled nanosheets directly grown on carbon paper (MSx NS@CP) as efficient counter electrodes for QDSSCs. Such CEs integrate the merits of fast electron transfer from interconnected conductive scaffold, efficient mass transfer from hierarchically vertical nanosheet on 3D open substrate, as well as abundant highly active catalytic sites from metal sulphide nanocrystal units. As a result, QDDSCs based on such CoS2 NS@CP and NiS NS@CP CEs achieve a PCE of 8.88% and 7.53%, respectively. The detailed analyses suggest that CoS2 NS@CP has the highest catalytic activity and shows the lowest charger transfer resistance, leading to the highest PCE. These findings may inspire the design and exploration of other self-supported efficient CEs by integrating highly active catalysts onto 3D conductive networks for efficient QDSSCs. 相似文献