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41.
Enhanced Degradation of Gaseous Xylene Using Surface Acidized TiO2 Catalyst with Non-thermal Plasmas
Wei Bolun Chen Yanping Ye Mingjie Shao Zhenhua He Yi Shi Yao 《Plasma Chemistry and Plasma Processing》2015,35(1):173-186
Plasma Chemistry and Plasma Processing - A plasma driven catalyst reactor was applied to the degradation of gaseous xylene combined with the TiO2 catalyst processed by an acidized treatment, which... 相似文献
42.
永磁向心轴承承载能力与刚度的计算 总被引:17,自引:1,他引:17
目前,尽管磁浮轴承技术的研究与开发应用已经受到国内外学者的广泛重视,但在永磁向心轴承承载能力的研究方面,却还存在着两个尚待解决的问题:一是将环形磁体作为无限长条形磁体处理,二是只能对轴承承载能力进行估算。针对这种情况,根据等效磁荷理论,在圆环状态下对轴向控制的永磁向心轴承的承载能力和刚度进行了研究,建立了永磁向心轴承承载能力数学模型,并对其计算结果作了试验验证,同时还提出了利用刚度系数建立的可供工程设计应用的永磁轴承承载能力和刚度的计算公式。结果表明,承载能力的计算值与实测值相当吻合;在偏心距的实际应用范围内,永磁向心轴承的径向刚度是个常量;内外磁环的轴向位移对磁轴承的承载能力和刚度都有明显的影响.因此,为了最大限度地提高这种轴承的承载能力和刚度,就要在设计其结构的过程中注意尽力保证内外磁环轴向对齐。 相似文献
43.
The potential energy curves of the low-lying electronic states of BeH+ molecular ion are performed by using highly accurate multi-reference configuration interaction with AV5Z basis sets for H atom and ACV5Z basis set for Be atom, 1s inner shell of Be is considered as the core orbit and the active orbit, respectively, which are used to characterise the spectroscopic properties of a manifold of singlet and triplet states. Fourteen electronic states correlated with eight dissociation channels are investigated, we have found that the a3Σ+ and c3Σ+ both are bound states, the 33Σ+ possesses double wells, and the C1Σ+, 33Σ+, 23Π, 21Π, 11Δ, 13Δ, 23Δ and 21Δ states are studied for the first time. Transition dipole moment, Franck–Condon factors qυ′υ″ and Einstein coefficients Aυ′υ″ for A1Σ+–X1Σ+, 21Π–B1Π, c3Σ+–a3Σ+ and b3Π–a3Σ+ systems have been calculated. Radiative lifetime of A1Σ+–X1Σ+ band system has also been determined. 相似文献
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45.
Yunfei Ru Ruochen Fang Zhandong Gu Lei Jiang Mingjie Liu 《Angewandte Chemie (International ed. in English)》2020,59(29):11876-11880
Synthetic gels with switchable interfacial properties have great potential in smart devices and controllable transport. Herein, we design an organogel by incorporating a binary liquid mixture with an upper critical solution temperature (UCST) into a polymer network, resulting in reversible modulation of lubrication and adhesion properties. As the temperature changes, the lubricating mechanism changes reversibly from boundary lubrication to hydrodynamic lubrication due to phase separation within the binary solution permeating the gel (friction coefficient 0.4–0.03). Droplets appear on the gel surface at low temperature and disappear with temperature higher than the critical phase separation temperature (Tps) of the organogel. The organogel possesses a relatively low ice adhesive strength (less than 1 kPa). This material has potential applications in anti‐icing and smart devices, and we believe that this design strategy can be expanded to other systems such as aqueous solutions and hydrogels. 相似文献
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47.
Mingjie Rong Jian Liu Zhen Sun Tong Li Yang Li Chunhuan Jiang Prof. Lehui Lu 《Angewandte Chemie (International ed. in English)》2023,62(19):e202216822
Pd-catalyzed chemistry has played a significant role in the growing subfield of bioorthogonal catalysis. However, rationally designing Pd nanocatalysts that show outstanding catalytic activity and good biocompatibility poses a great challenge. Herein, we propose an innovative strategy through exploiting black phosphorous nanosheets (BPNSs) to enhance Pd-mediated bioorthogonal catalytic activity. Firstly, the electron-donor properties of BPNSs enable in situ growth of Pd nanoparticles (PdNPs) on it. Meanwhile, due to the superb capability of reducing PdII, BPNSs can act as hard nucleophiles to accelerate the transmetallation in the decaging reaction process. Secondly, the lone pair electrons of BPNSs can firmly anchor PdNPs on their surface via Pd−P bonds. This design endows Pd/BP with the capability to retard tumor growth by activating prodrugs. This work proposes new insights into the design of heterogeneous transition-metal catalysts (TMCs) for bioorthogonal catalysis. 相似文献
48.
Tongle Xu Zhenghui Luo Ruijie Ma Zhanxiang Chen Top Archie Dela Peña Heng Liu Qi Wei Mingjie Li Cai'e Zhang Jiaying Wu Xinhui Lu Gang Li Chuluo Yang 《Angewandte Chemie (International ed. in English)》2023,62(30):e202304127
The central core in A-DA1D-A-type small-molecule acceptor (SMAs) plays an important role in determining the efficiency of organic solar cells (OSCs), while the principles governing the efficient design of SMAs remain elusive. Herein, we developed a series of SMAs with pyrido[2,3-b]quinoxaline (PyQx) as new electron-deficient unit by combining with the cascade-chlorination strategy, namely Py1, Py2, Py3, Py4 and Py5. The introduction of chlorine atoms reduces the intramolecular charge transfer effects but elevates the LUMO values. Density functional theory (DFT) reveals that Py2 with ortho chlorine substituted PyQx and Py5 with two chlorine atoms yield larger dipole moments and smaller π⋅⋅⋅π stacking distances, as compared with the other three acceptors. Moreover, Py2 shows the strongest light absorption capability induced by extended orbit overlap lengths and more efficient packing structures in the dimers. These features endow the best device performance of Py2 due to the better molecular packing and aggregation behaviors, more suitable domain sizes with better exciton dissociation and charge recombination. This study highlights the significance of incorporating large dipole moments, small π⋅⋅⋅π stacking distances and extended orbit overlap lengths in dimers into the development of high-performance SMAs, providing insight into the design of efficient A-DA1D-A-type SMAs for OSCs. 相似文献
49.
Simultaneous determination and pharmacokinetic study of four phenol compounds in rat plasma by ultra‐high performance liquid chromatography with tandem mass spectrometry after oral administration of Echinacea purpurea extract 下载免费PDF全文
Chunli Gan Lu Liu Yan Du Liqian Wang Mingjie Gao Lijun Wu Chunjuan Yang 《Journal of separation science》2016,39(9):1628-1637
A rapid and sensitive assay based on ultra‐high performance liquid chromatography with electrospray ionization tandem mass spectrometry was established and validated for the simultaneous determination of cichoric acid, chlorogenic acid, quinic acid, and caffeic acid in rat plasma after oral administration of Echinacea purpurea extract using butylparaben as the internal standard. Samples were pretreated by liquid–liquid extraction with ethyl acetate. The separations for analytes were performed on an ACQUITY UPLC HSS C18 column (1.8 μm 2.1 × 100 mm) using a gradient elution program with acetonitrile/10 mM ammonium acetate (pH 5.6) at a flow rate of 0.3 mL/min. The analytes were detected in multiple reaction monitoring mode with negative electrospray ionization. The lower limit of quantification of each analyte was not higher than 10.85 ng/mL. The relative standard deviation of the intraday and interday precisions was less than 14.69%. The relative errors of accuracies were in the range of –13.80 to 14.91%. The mean recoveries for extraction recovery and matrix effect were higher than 80.79 and 89.98%, respectively. The method validation results demonstrated that the proposed method was sensitive, specific, and reliable, which was successfully applied to the pharmacokinetic study of four components after oral administration of Echinacea purpurea extract. 相似文献
50.
Pranav P. Sharma Jingjie Wu Ram Manohar Yadav Mingjie Liu Christopher J. Wright Chandra Sekhar Tiwary Boris I. Yakobson Jun Lou Pulickel M. Ajayan Xiao‐Dong Zhou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(46):13905-13909
Nitrogen‐doped carbon nanotubes (NCNTs) have been considered as a promising electrocatalyst for carbon‐dioxide‐reduction reactions, but two fundamental chemistry questions remain obscure: 1) What are the active centers with respect to various defect species and 2) what is the role of defect density on the selectivity of NCNTs? The aim of this work is to address these questions. The catalytic activity of NCNTs depends on the structural nature of nitrogen in CNTs and defect density. Comparing with pristine CNTs, the presence of graphitic and pyridinic nitrogen significantly decreases the overpotential (ca. −0.18 V) and increases the selectivity (ca. 80 %) towards the formation of CO. The experimental results are in congruent with DFT calculations, which show that pyridinic defects retain a lone pair of electrons that are capable of binding CO2. However, for graphitic‐like nitrogen, electrons are located in the π* antibonding orbital, making them less accessible for CO2 binding. 相似文献