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51.
Song Zhang Luke A. Galuska Xiaodan Gu 《Journal of polymer science. Part A, Polymer chemistry》2022,60(7):1108-1129
Thin films with a nanometer-scale thickness are of great interest to both scientific and industrial communities due to their numerous applications and unique behaviors different from the bulk. However, the understanding of thin-film mechanics is still greatly hampered due to their intrinsic fragility and the lack of commercially available experimental instruments. In this review, we first discuss the progression of thin-film mechanical testing methods based on the supporting substrate: film-on-solid substrate method, film-on-water tensile tests, and water-assisted free-standing tensile tests. By comparing past studies on a model polymer, polystyrene, the effect of different substrates and confinement effect on the thin-film mechanics is evaluated. These techniques have generated fruitful scientific knowledge in the field of organic semiconductors for the understanding of structure–mechanical property relationships. We end this review by providing our perspective for their bright prospects in much broader applications and materials of interest. 相似文献
52.
Ming-Qiang Huang Huan-Huan Wang Xiao-Bin Shan Liu-Si Sheng Chang-Jin Hu Xue-Jun Gu Wei-Jun Zhang 《中国化学会会志》2023,70(4):938-948
Secondary organic aerosol (SOA) produced by ozonolysis of styrene and other alkene compounds is a major part of fine particles in urban atmospheres. The atmospheric ozonolysis process of styrene is simulated in a smog chamber, and the formed SOA particles are detected on-line by a synchronous radiation vacuum ultraviolet photoionization mass spectrometer (VUV-PIMS) in this study. Through molecular ion peaks in the photonionization mass spectra of SOA and the corresponding photoionization efficiency curve, combined with off-line measurement verification of ultraviolet visible and infrared absorption spectra, it is determined that formaldehyde, formic acid, benzene, phenol, benzaldehyde, and benzoic acid are the main constituents of styrene SOA. These provide new information for studying the atmospheric ozonolysis oxidation mechanism of styrene. VUV-PIMS can get over complicated sample preparation procedures, secondary pollution, and other shortcomings of the off-line method and is a useful instrument to measure constituents and unveil the formation process of SOA particles. 相似文献
53.
54.
Shuangxi Jing Ren Sheng Dr. Xinxin Liang Prof. Dong Gu Dr. Yuhao Peng Prof. Juanxiu Xiao Prof. Yijun Shen Prof. Di Hu Prof. Wei Xiao 《Angewandte Chemie (International ed. in English)》2023,62(6):e202216315
An overall carbon-neutral CO2 electroreduction requires enhanced conversion efficiency and intensified functionality of CO2-derived products to balance the carbon footprint from CO2 electroreduction against fixed CO2. A liquid Sn cathode is herein introduced into electrochemical reduction of CO2 in molten salts to fabricate core–shell Sn−C spheres (Sn@C). An in situ generated Li2SnO3/C directs a self-template formation of Sn@C. Benefitting from the accelerated reaction kinetics from the liquid Sn cathode and the core–shell structure of Sn@C, a CO2-fixation current efficiency higher than 84 % and a high reversible lithium-storage capacity of Sn@C are achieved. The versatility of this strategy is demonstrated by other low melting point metals, such as Zn and Bi. This process integrates energy-efficient CO2 conversion and template-free fabrication of value-added metal-carbon, achieving an overall carbon-neutral electrochemical reduction of CO2. 相似文献
55.
Dr. Yuxuan Hu Dr. Jingsheng Miao Dr. Cheng Zhong Yang Zeng Prof. Shaolong Gong Dr. Xiaosong Cao Xue Zhou Dr. Yu Gu Prof. Chuluo Yang 《Angewandte Chemie (International ed. in English)》2023,62(19):e202302478
Heavy-atom integration into thermally activated delayed fluorescence (TADF) molecule could significantly promote the reverse intersystem crossing (RISC) process. However, simultaneously achieving high efficiency, small roll-off, narrowband emission and good operational lifetime remains a big challenge for the corresponding organic light-emitting diodes (OLEDs). Herein, we report a pure green multi-resonance TADF molecule BN-STO by introducing a peripheral heavy atom selenium onto the parent BN-Cz molecule. The organic light-emitting diode device based on BN-STO exhibited state-of-the-art performance with a maximum external quantum efficiency (EQE) of 40.1 %, power efficiency (PE) of 176.9 lm W−1, well-suppressed efficiency roll-off and pure green gamut. This work reveals a feasible strategy to reach a balance between fast RISC process and narrow full width at half maximum (FWHM) of MR-TADF by heavy atom effect. 相似文献
56.
Di Liu Jiyan Pei Prof. Xu Zhang Xiao-Wen Gu Prof. Hui-Min Wen Prof. Banglin Chen Prof. Guodong Qian Prof. Bin Li 《Angewandte Chemie (International ed. in English)》2023,62(12):e202218590
Developing porous materials for C3H6/C3H8 separation faces the challenge of merging excellent separation performance with high stability and easy scalability of synthesis. Herein, we report a robust Hofmann clathrate material (ZJU-75a), featuring high-density strong binding sites to achieve all the above requirements. ZJU-75a adsorbs large amount of C3H6 with a record high storage density of 0.818 g mL−1, and concurrently shows high C3H6/C3H8 selectivity (54.2) at 296 K and 1 bar. Single-crystal structure analysis unveil that the high-density binding sites in ZJU-75a not only provide much stronger interactions with C3H6 but also enable the dense packing of C3H6. Breakthrough experiments on gas mixtures afford both high separation factor of 14.7 and large C3H6 uptake (2.79 mmol g−1). This material is highly stable and can be easily produced at kilogram-scale using a green synthesis method, making it as a benchmark material to address major challenges for industrial C3H6/C3H8 separation. 相似文献
57.
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
58.
Kevin Doyle Maxine Roberts Jenna Harvey Richard Hewer Matthias Zebisch Victor Rangel Meigang Gu Yiming Wu Lichao Yang Mark Carlton Lee Dawson Roland Bürli 《Helvetica chimica acta》2023,106(9):e202300080
Brain concentrations of nicotinamide adenine dinucleotide (NAD+), an important cellular co-factor, tend to decrease with age and in neurodegeneration. As the NADase cluster of differentiation 38 (CD38) significantly contributes to NAD+ consumption, we reasoned that CD38 inhibition may be of therapeutic value for CNS disorders. The new pyrazole compound was designed based on a known CD38 inhibitor and showed good inhibitory potency. Several attempts to co-crystallise this pyrazole with CD38 and cyclic adenosine diphosphate ribose (cADPR) culminated in a high-resolution X-ray structure, in which the pyrazolyl group in the new compound formed a covalent bond with one of the ribosyl units of cADPR. This reaction proceeded under retention of configuration and resulted in a neutral ribosyl-pyrazole conjugate that is embedded within the active site of the enzyme. An analysis of this structural complex gave rise to design principles that enabled the preparation of more potent CD38 inhibitors with drug-like properties. 相似文献
59.
Dr. Yinxiang Zeng Zhihao Pei Dr. Yan Guo Dr. Deyan Luan Prof. Xiaojun Gu Prof. Xiong Wen Lou 《Angewandte Chemie (International ed. in English)》2023,62(45):e202312145
Constructing multifunctional interphases to suppress the rampant Zn dendrite growth and detrimental side reactions is crucial for Zn anodes. Herein, a phytic acid (PA)-ZnAl coordination compound is demonstrated as a versatile interphase layer to stabilize Zn anodes. The zincophilic PA-ZnAl layer can manipulate Zn2+ flux and promote rapid desolvation kinetics, ensuring the uniform Zn deposition with dendrite-free morphology. Moreover, the robust PA-ZnAl protective layer can effectively inhibit the hydrogen evolution reaction and formation of byproducts, further contributing to the reversible Zn plating/stripping with high Coulombic efficiency. As a result, the Zn@PA-ZnAl electrode shows a lower Zn nucleation overpotential and higher Zn2+ transference number compared with bare Zn. The Zn@PA-ZnAl symmetric cell exhibits a prolonged lifespan of 650 h tested at 5 mA cm−2 and 5 mAh cm−2. Furthermore, the assembled Zn battery full cell based on this Zn@PA-ZnAl anode also delivers decent cycling stability even under harsh conditions. 相似文献
60.
Jingcheng Wu Leitao Xu Zhijie Kong Kaizhi Gu Yuxuan Lu Xianwen Wu Prof. Yuqin Zou Prof. Shuangyin Wang 《Angewandte Chemie (International ed. in English)》2023,62(45):e202311196
Alanine is widely employed for synthesizing polymers, pharmaceuticals, and agrochemicals. Electrocatalytic coupling of biomass molecules and waste nitrate is attractive for the nitrate removal and alanine production under ambient conditions. However, the reaction efficiency is relatively low due to the activation of the stable substrates, and the coupling of two reactive intermediates remains challenging. Herein, we realize the integrated tandem electrochemical-chemical-electochemical synthesis of alanine from the biomass-derived pyruvic acid (PA) and waste nitrate (NO3−) catalyzed by PdCu nano-bead-wires (PdCu NBWs). The overall reaction pathway is demonstrated as a multiple-step catalytic cascade process via coupling the reactive intermediates NH2OH and PA on the catalyst surface. Interestingly, in this integrated tandem electrochemical-chemical-electrochemical catalytic cascade process, Cu facilitates the electrochemical reduction of nitrate to NH2OH intermediates, which chemically couple with PA to form the pyruvic oxime, and Pd promotes the electrochemical reduction of pyruvic oxime to the desirable alanine. This work provides a green strategy to convert waste NO3− to wealth and enriches the substrate scope of renewable biomass feedstocks to produce high-value amino acids. 相似文献