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181.
Dr. Yong-Zhi Li Gang-Ding Wang Hong-Yun Yang Prof. Lei Hou Prof. Yao-Yu Wang Prof. Zhonghua Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(69):16402-16407
To develop efficient adsorbent materials for storage and separation of C2H2, an unprecedented supercage MOF, [Me2NH2]⋅[Zn3(ALP)(TDC)2.5]⋅3.5DMF⋅2 H2O ( 1 ) was constructed through medicinal molecule allopurinol (ALP) and S-containing 2,5-thiophenedicarboxylic acid (H2TDC). 1 contains a novel linear trinuclear cluster that is composed by ALP and carboxylates and forms a final uncommon 5-connected yfy topological framework. The framework possesses three types of interlinked cages decorated by rich functional sites, and reveals not only high adsorption capacity for C2H2 but also excellent selective separation for C2H2/CO2 and C2H2/CH4 at 298 K. Dynamic breakthrough experiments on C2H2/CO2 (1:1) mixture and C2H2/CH4 (1:1) mixture also demonstrated the potential of the material to separate C2H2 from CO2 or CH4 mixtures. Molecular simulations were also studied to identify the different CO2- and C2H2- binding sites in 1 , such as carboxylate groups, S atoms and carbonyl groups. 相似文献
182.
Yingjun Sun Dr. Yingjie Li Yingnan Qin Prof. Lei Wang Prof. Shaojun Guo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(18):4032-4038
Searching for new anti-poisoning Pt-based catalysts with enhanced activity for alcohol oxidation is the key in direct alcohol fuel cells (DAFCs). However, in the traditional strategy for designing bimetallic or multimetallic alloy is still difficult to achieve a satisfactory heterogeneous electrocatalyst because the activity often depends on only the surface atoms. Herein, we fabricate the multicomponent active sites by creating a sulfide structure on 1D PtNiCo trimetallic nanowires (NWs), to give a PtNiCo/NiCoS interface NWs (IFNWs). Owing to the presence of sulfide interfaces, the PtNiCo/NiCoS IFNWs enable an impressive methanol/ethanol oxidation reaction (MOR/EOR) performance and excellent anti-CO poisoning tolerance. They have the MOR and EOR mass activities of 2.25 Amg-1Pt and 1.62 Amg-1Pt, around 1.26, 3.21 and 1.46, 2.96 times higher than those of PtNiCo NWs and commercial Pt/C, respectively. CO-stripping and XPS measurements further demonstrate that the new interfacial structure and optimal bonding of Pt−CO can result in accelerating the removal of surface adsorbed carbonaceous intermediates. Moreover, such a unique structure has also demonstrated a much-improved ability for the electrochemical detection of some important molecules (H2O2 and NH2NH2). 相似文献
183.
Zhou Shuiping Zhou Xiaoyang Tang Gen Guo Xiang Pang Aimin 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2529-2540
Journal of Thermal Analysis and Calorimetry - Differences of thermal decomposition characteristics and combustion properties between CL-20-based propellants and HMX-based propellants were... 相似文献
184.
Chen Dan Dan He Zhi Qiang Wang Min Wu Di Chen Xiang Ying Zhang Zhong Jie 《Journal of Solid State Electrochemistry》2020,24(3):641-654
Journal of Solid State Electrochemistry - In the present work, we demonstrate a strategy of combining boron doping and porosity engineering for a highly modulated carbon component and pore... 相似文献
185.
We classify all Leibniz conformal algebras of rank two. 相似文献
186.
Xiang Hao Kaixiang Yang Hairong Wang Feng Peng Haiyang Yang 《Angewandte Chemie (International ed. in English)》2020,59(11):4314-4319
Non‐Newtonian fluids are ubiquitous in daily life and industrial applications. Herein, we report an intelligent fluidic system integrating two distinct non‐Newtonian rheological properties mediated by an autocatalytic enzyme reaction. Associative polyelectrolytes bearing a small amount of ionic and alkyl groups are engineered: by carefully balancing the charge density and the hydrophobic effect, the polymer solutions demonstrate a unique shear thickening property at low pH while shear thinning at high pH. The urea‐urease clock reaction is utilized to program a feedback‐induced pH change, leading to a strong upturn of the nonlinear viscoelastic properties. As long as the chemical fuel is supplied, two distinct non‐Newtonian states can be achieved with a tunable lifetime span. As a proof of concept, we demonstrate how the physical energy‐driven nonequilibrium properties can be manipulated by a chemical‐fueled process. 相似文献
187.
Long-term pulmonary exposure to multi-walled carbon nanotubes (MWCNTs) may promote breast cancer metastasis and rapid colonization in the lungs and other organs according to recent research conducted by Prof.Chunying Chen,Prof.Tao Zhu and their colleagues,published in Nature Nanotechnology [1]. 相似文献
188.
Shuangfei Xiang Ting Li Weifu Dong Qinghua Lu 《Journal of polymer science. Part A, Polymer chemistry》2018,56(21):1469-1474
In this article, we report a synergistic strategy to develop dual physically cross-linked tough hydrogels via one-pot bulk copolymerization of N-vinyl-2-pyrrolidone, acrylic acid, and stearyl methylacrylate (SMA) without any adscititious surfactant. Due to synergic effects of hydrogen bonding and hydrophobic association, the resulted dual physically cross-linked hydrogels (DP Gel) with ultra-wide range adjustable Young's modulus (0.08–45.6 MPa), tensile stress (0.7–6.9 MPa), and toughness (3.3–23.1 MJ m−3). Stretching to 300%, DP Gel exhibited fast recoverability that remained ~95% of initial dissipated energy after resting in 60 °C for 3 min. Finally, scanning electron microscopy revealed that the microstructure of hydrogel changed from phase separation structure to micro phase separation as SMA added, which accounted for excellent performance of DP Gel. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1469–1474 相似文献
189.
Xiang Wang 《Optics Communications》2009,282(14):2841-3034
In this paper, an athermal silicon arrayed waveguide grating (AWG) with the assistance of a polymer-filled slot structure is proposed. Arrayed slot waveguides were used to replace arrayed silicon photonic wires (SPWs). By carefully controlling the temperature dependence of the effective index of the polymer-filled slot waveguides, the athermal silicon AWG is realized. Analysis shows that the center wavelength shift of the AWG can be down to 0.14 pm/°C. 相似文献
190.
采用多层介质膜衍射光栅实现多路高功率光纤激光共孔径光谱合成有望成为光纤激光同时实现高功率、高效率和高光束质量的最具发展潜力的技术途径。搭建了一套基于双光栅色散补偿设计的5 kW共孔径光谱合成系统。采用国产多层介质膜衍射光栅实现了5路kW级窄谱子束激光的高效优质共孔径光谱合成,最大输出功率达5.07 kW,光束质量因子(M2)小于3,合成效率达到91.2%。初步研究表明:多层介质膜衍射光栅在较高功率水平、较宽光谱范围内均能保持较高衍射效率,是实现高功率光纤激光高效率光谱合成的重要器件;参与合成的子束自身的光束质量水平和线宽是影响合成输出光束质量的重要因素,光谱合成系统的输出功率主要受限于窄谱子束的输出功率和合成路数,增加窄谱子束的功率或合成路数均可进一步提升系统的输出功率。 相似文献