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991.
Shu Xia Wang Yan Qin Yongqiang Yu Cuiping Zhang Jianfang Zhao Jiebo Cui Jiewu Cui Lihua Zheng Hongmei Zhang Yong Wang Wenfang Wu Yucheng 《Journal of Solid State Electrochemistry》2017,21(5):1489-1497
Journal of Solid State Electrochemistry - Binder-free, high-performance electrode materials play a critical role for supercapacitors. In this paper, through the electrochemical anodization process,... 相似文献
992.
应用密度泛函理论,在DZP基组水平上研究了(5,5)型锗纳米管催化的氧还原反应(ORR)的性能以及可能的催化机理.计算结果表明,ORR在锗纳米管上可能经历O2解离、OOH解离、H2O2解离三种可能机理.无论是对哪种机理,整个ORR均遵循四电子反应路径.评估ORR性能的重要中间产物O和OH的吸附能分别为-4.33 eV和-2.21 eV,这与它们在贵金属铂(Pt)上的吸附能非常接近.此外,在GeNT上,整个ORR过程中最后一步生成的H2O分子的吸附能仅仅为-0.05 eV,比O2分子的吸附能弱得多,意味着整个ORR催化循环在GeNT上可以顺利更替.因此,联合ORR的反应能量数据和中间产物的吸附数据,可以认为(5,5)型锗纳米管具有类Pt的催化性能.溶剂效应计算结果表明,一些反应中间产物的吸附结构,如O中间体会在很大程度上受到溶剂效应的影响.对所研究的锗纳米管来说,溶剂效应可以促进其催化的ORR进程. 相似文献
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995.
高速通道压裂是近年在非常规致密油气资源开采中出现的新工艺, 已在世界范围内推广实施, 并取得了良好的增产效果. 该技术可使支撑剂在人工压裂缝中形成簇团式分布, 从而形成油气高速流动通道, 提高裂缝的导流能力. 但目前对于高速通道压裂裂缝高导流能力的形成机理及其影响因素尚不清楚. 对此, 本文从流体力学理论出发, 首先将高速通道压裂裂缝内形成的支撑剂簇团视为渗流区域, 簇团间的大通道视为自由流动区域; 然后基于Darcy-Brinkman方程建立了裂缝内的流动数学模型, 采用均匀化理论对该流动数学模型进行了尺度升级, 推导得到了高速通道压裂裂缝的渗透率, 揭示了其高导流能力的形成机理; 并以此为基础, 分析了不同支撑剂簇团形状、大小以及分布方式等因素对其导流能力的影响, 可为高速通道压裂工艺参数设计与优化提供基础. 相似文献
996.
Dr. Xianghe Meng Xingyu Zhang Qingxiong Liu Dr. Zhengyang Zhou Dr. Xingxing Jiang Prof. Yonggang Wang Prof. Zheshuai Lin Prof. Mingjun Xia 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(1):e202214848
Nonlinear optical (NLO) crystal, which simultaneously exhibits strong second-harmonic-generation (SHG) response and desired optical anisotropy, is a core optical material accessible to the modern optoelectronics. Accompanied by strong SHG effect in a NLO crystal, a contradictory problem of overlarge birefringence is ignored, leading to low frequency doubling efficiency and poor beam quality. Herein, a series of rare earth cyanurates RE5(C3N3O3)(OH)12 (RE=Y, Yb, Lu) were successfully characterized by 3D electron diffraction technique. Based on a “three birds with one stone” strategy, they enable the simultaneous fulfillment of strong SHG responses (2.5–4.2× KH2PO4), short UV cutoff (ca. 220 nm) and applicable birefringence (ca. 0.15 at 800 nm) by the introduction of rare earth coordination control of π-conjugated (C3N3O3)3− anions. These findings provide high-performance short-wavelength NLO materials and highlight the exploration of cyanurates as a new research area. 相似文献
997.
Prof. Dr. Yuandong Xu Binyang Liu Chaoyang Dong Haoyang Feng Prof. Dr. Yajun Wei Prof. Dr. Xia Zhang 《欧洲无机化学杂志》2023,26(1):e202200569
Three-dimensional (3D) heterostructured molybdenum disulfide (MoS2) is used as base materials for aniline monomer in situ polymerization on its surface. It is found that the aniline addition has a remarkable effect on the energy storage of the final compounds due to the improvement of the conductivity and structure stability combined with the synergistic effect between the two types of species. The optimal compound of PANI@MoS2-150 not only shows a high capacitance value of 801.4 F ⋅ g−1 at a current density of 0.5 A ⋅ g−1 but also provides a high retention rate of 77.4 % after 10,000 cycles. The capacitance fading may be due to the increase of the internal resistance analyzed by EIS. Furthermore, a flexible symmetric supercapacitor based on PANI@MoS2-150 has also been fabricated and the specific capacitance reaches 105 F ⋅ g−1 at a current density of 1 A ⋅ g−1. Impressively, the capacitance retention is larger than 100 % undergoing 10,000 cycles. Besides, the highest energy density of 21 Wh ⋅ kg−1 was obtained. Additionally, the fabricated symmetric supercapacitor demonstrates excellent flexibility. 相似文献
998.
Ibrahim Y. Wakai Qiulin Wang Jing Zhao Xiaoyu Wang Shihai Xia Wencheng Zhang Wei Xu Yakai Feng 《先进技术聚合物》2023,34(2):531-538
As the clinical demand for blood-contacting materials increases, higher requirements are placed on their physicochemical properties, durability and hemocompatibility in vivo. In this work, a multiple functionalized material was developed through a facile modification process. Herein, polycarbonate urethane (PCU) surface was co-modified with polyethylene glycol (PEG) and bivalirudin (BVLD). PCU provides excellent physical and mechanical properties, PEG and BVLD, especially BVLD, enable the surface with outstanding anticoagulant capacity. Specifically, PCU surface was first treated with hexamethylene diisocyanate to introduce active isocyanate groups onto the surface, followed by hydroxy-PEG grafting to improve the hydrophilicity. Finally, BVLD was immobilized on the surface via Michael addition reaction to improve antithrombotic properties. Attenuated total reflection Fourier transforms infrared spectroscopy and UV spectrophotometers were used to confirm the modified surfaces. The hydrophilicity was characterized by static water contact angle measurement, the morphology of the modified surfaces was observed by scanning electron microscopy. Blood compatibility of the modified surfaces was characterized by the hemolysis rate, platelet adhesion assay and cell culture test. The results showed that the BVLD immobilized surface has excellent anticoagulant properties, good fibrin-bound thrombin inhibition, and good resistance against non-specific adhesion of proteins. Hence, the co-modification with PEG and BVLD was proved an encouraging strategy for improving hemocompatibility. 相似文献
999.
以Ce3+为中心离子,N,N-二甲基甲酰胺(DMF)为有机配体,通过温度调节,合成系列形貌和电化学信号不同的铈配合物(Ce-COPs)。筛选出电化学信号最强的多面体状Ce-COP为信号探针。通过凝血酶(TB)与TB适体链之间的特异性识别作用,设计了一种简单通用的TB适体传感器。最优实验条件下,该传感器对TB的线性响应范围为1.0 fmol·L-1~1.0 nmol·L-1,检测限为0.94 fmol·L-1。此外,本方案方法与商品人凝血酶(TM) ELISA试剂盒检测结果相近。结果表明,我们构建的TB适体传感器具有良好的灵敏度、特异性、选择性和稳定性。 相似文献
1000.
Mingxia Guo Long Fang Linlin Zhang Mingzhu Li Meiyu Cong Xiping Guan Chuanwei Shi ChunLei Gu Xia Liu Yong Wang Xin Ding 《Angewandte Chemie (International ed. in English)》2023,62(13):e202217635
Atomically dispersed Fe was designed on TiO2 and explored as a Janus electrocatalyst for both nitrogen oxidation reaction (NOR) and nitrogen reduction reaction (NRR) in a two-electrode system. Pulsed electrochemical catalysis (PE) was firstly involved to inhibit the competitive hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Excitingly, an unanticipated yield of 7055.81 μmol h−1 g−1cat. and 12 868.33 μmol h−1 g−1cat. were obtained for NOR and NRR at 3.5 V, respectively, 44.94 times and 7.8 times increase in FE than the conventional constant voltage electrocatalytic method. Experiments and density functional theory (DFT) calculations revealed that the single-atom Fe could stabilize the oxygen vacancy, lower the energy barrier for the vital rupture of N≡N, and result in enhanced N2 fixation performance. More importantly, PE could effectively enhance the N2 supply by reducing competitive O2 and H2 agglomeration, inhibit the electrocatalytic by-product formation for longstanding *OOH and *H intermediates, and promote the non-electrocatalytic process of N2 activation. 相似文献