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91.
The molecular orbitals obtained from conventional quantum chemistry calculations, are expressed in terms of symmetrized valence bond functions of fragment, and a direct picture of chemical bonding can be drawn easily. This method is utilized, together with extended Huckel calculations, to interpret the bonding properties of a centipede-like chain structure for novel laser-producing boranes B3k+pH?5k+p+3 which is constructed from the repeated unit B3H5 halted to each other by three B—H—B bonds. 相似文献
92.
Prof. Shuaijun Yang Ping-An Yin Lin Li Prof. Qian Peng Prof. Xinggui Gu Prof. Ge Gao Prof. Jingsong You Prof. Ben Zhong Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(25):10222-10228
Squaraines (SQs) with tunable emission in the solid state is of great importance for various demands; however a remaining challenge is emission quenching upon aggregation. Herein, a unique SQ, named as CIEE-SQ, is designed to exhibit strong emission in crystal, undergoing crystallization-induced reverse from dark 1(n+σ,π*) to bright 1(π,π*) excited states. Such an excited state of CIEE-SQ can be subtly tuned by molecular conformation changes during the unexpected temperature-triggered single-crystal to single-crystal (SCSC) reversible transformation. Furthermore, co-crystallization between CIEE-SQ and chloroform largely stabilize the 1(π,π*) state, enhancing the transition dipole moment and decreasing the reorganization energy to boost the fluorescence, which is promising in data encryption and decryption. 相似文献
93.
Dr. Weihui Ou Dr. Binbin Zhou Junda Shen Dr. Tsz Wing Lo Prof. Dangyuan Lei Dr. Shengliang Li Jing Zhong Prof. Yang Yang Li Prof. Jian Lu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(17):6856-6859
Hot carriers (HCs) and thermal effects, stemming from plasmon decays, are crucial for most plasmonic applications. However, quantifying these two effects remains extremely challenging due to the experimental difficulty in accurately measuring the temperature at reaction sites. Herein, we provide a novel strategy to disentangle HCs from photothermal effects based on the different traits of heat dissipation (long range) and HCs transport (short range), and quantitatively uncover the dominant and potential-dependent role of photothermal effect by investigating the rapid- and slow-response currents in plasmon-mediated electrochemistry at nanostructured Ag electrode. Furthermore, the plasmoelectric surface potential is found to contribute to the rapid-response currents, which is absent in the previous studies. 相似文献
94.
Dr. Shuang Pan Dr. Haiyang Zou Aurelia C. Wang Dr. Zewei Wang Jiwoo Yu Chuntao Lan Qiliang Liu Prof. Zhong Lin Wang Prof. Tianquan Lian Prof. Juan Peng Prof. Zhiqun Lin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(35):15052-15059
Despite recent progress in producing perovskite nanowires (NWs) for optoelectronics, it remains challenging to solution-print an array of NWs with precisely controlled position and orientation. Herein, we report a robust capillary-assisted solution printing (CASP) strategy to rapidly access aligned and highly crystalline perovskite NW arrays. The key to the CASP approach lies in the integration of capillary-directed assembly through periodic nanochannels and solution printing through the programmably moving substrate to rapidly guide the deposition of perovskite NWs. The growth kinetics of perovskite NWs was closely examined by in situ optical microscopy. Intriguingly, the as-printed perovskite NWs array exhibit excellent optical and optoelectronic properties and can be conveniently implemented for the scalable fabrication of photodetectors. 相似文献
95.
Dr. Chengzhi Jin Fengyin Liang Dr. Jinquan Wang Dr. Lili Wang Dr. Jiangping Liu Xinxing Liao Dr. Thomas W. Rees Bo Yuan Prof. Dr. Hui Wang Prof. Dr. Yong Shen Prof. Dr. Zhong Pei Prof. Dr. Liangnian Ji Prof. Dr. Hui Chao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16121-16125
Compared to 2PE (two-photon excitation) microscopy, 3PE microscopy has superior spatial resolution, deeper tissue penetration, and less defocused interference. The design of suitable agents with a large Stokes shift, good three-photon absorption (3PA), subcellular targeting, and fluorescence lifetime imaging (FLIM) properties, is challenging. Now, two IrIII complexes (3PAIr1 and 3PAIr2) were developed as efficient three-photon phosphorescence (3PP) agents. Calculations reveal that the introduction of a new group to the molecular scaffold confers a quadruple promotion in three-photon transition probability. Confocal and lifetime imaging of mitochondria using IrIII complexes as 3PP agents is shown. The complexes exhibit low working concentration (50 nm ), fast uptake (5 min), and low threshold for three-photon excitation power (0.5 mW at 980 nm). The impressive tissue penetration depth (ca. 450 μm) allowed the 3D imaging and reconstruction of brain vasculature from a living specimen. 相似文献
96.
Guangrui Chen Yuxing Yan Dr. Jie Wang Prof. Yong Sik Ok Guiyuan Zhong Prof. Bu Yuan Guan Prof. Yusuke Yamauchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(44):19831-19836
Mesoporous core–shell nanostructures with controllable ultra-large open channels in their nanoshells are of great interest. However, soft template-directed cooperative assembly to mesoporous nanoshells with highly accessible pores larger than 30 nm, or even above 50 nm into macroporous range, remains a significant challenge. Herein we report a general approach for precisely tailored coating of hierarchically macro-/mesoporous polymer and carbon shells, possessing highly accessible radial channels with extremely wide pore size distribution from ca. 10 nm to ca. 200 nm, on diverse functional materials. This strategy creates opportunities to tailor the interfacial assembly of irregular mesostructured nanounits on core materials and generate various core–shell nanomaterials with controllable pore architectures. The obtained Fe,N-doped macro-/mesoporous carbon nanoshells show enhanced electrochemical performance for the oxygen reduction reaction in alkaline condition. 相似文献
97.
Dr. Haoxuan Li Haifei Wen Dr. Zhijun Zhang Dr. Nan Song Prof. Ryan T. K. Kwok Prof. Jacky W. Y. Lam Prof. Lei Wang Prof. Dong Wang Prof. Ben Zhong Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(46):20551-20555
Using reverse thinking of the aggregation-induced emission (AIE) principle, we demonstrate an ingenious and universal protocol for amplifying molecular motions to boost photothermal efficiency of fibers. Core–shell nanofibers having the olive oil solution of AIE-active molecules as the core surrounded by PVDF-HFP shell were constructed by coaxial electrospinning. The molecularly dissolved state of AIE-active molecules allows them to freely rotate and/or vibrate in nanofibers upon photoexcitation and thus significantly elevates the proportion of non-radiative energy dissipation, affording impressive heat-generating efficiency. Photothermal evaluation shows that the core–shell nanofibers with excellent durability can reach up to 22.36 % of photothermal conversion efficiency, which is 26-fold as the non-core–shell counterpart. Such a core–shell fiber can be used for photothermal textiles and solar steam generation induced by natural sunlight with green and carbon-zero emission. 相似文献
98.
Prof. Ping Yu Huan Wei Peipei Zhong Yifei Xue Dr. Fei Wu Dr. Yang Liu Prof. Junjie Fei Prof. Lanqun Mao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(50):22841-22847
The development of new principles and techniques with high neuronal compatibility for quantitatively monitoring the dynamics of neurochemicals is essential for deciphering brain chemistry and function but remains a great challenge. We herein report a neuron-compatible method for in vivo neurochemical sensing by powering a single carbon fiber through spontaneous bipolar electrochemistry as a new sensing platform. By using ascorbic acid as a model target to prove the concept, we found that the single-carbon-fiber-powered microsensor exhibited a good response, high stability and, more importantly, excellent neuronal compatibility. The microsensor was also highly compatible with electrophysiological recording, thus enabling the synchronous recording of both chemical and electrical signals. The sensing principle could be developed for in vivo monitoring of various neurochemicals in the future by rationally designing and tuning the electrochemical reactions at the two poles of the carbon fiber. 相似文献
99.
Zhong Yingying Li Qing-lan Lu Minglei Wang Tiantian Yang Huiyi He Qiyi Cui Xiping Li Xiangguang Zhao Suqing 《Mikrochimica acta》2020,187(12):1-11
Microchimica Acta - Testing gluten content in food, before it reaches the consumer, becomes a major challenge where cross-contamination during processing and transportation is a very common... 相似文献
100.
PENG Xiaoyu ZHAO Anran HUANG Kelin HU Tingju LIU Buming HUANG Yan CHEN Hailan CHAI Ling LIN Cuiwu 《高等学校化学研究》2020,36(5):795-803
Structural modification of native compounds is an effective way to develop new drugs with increased pharmacological activities and improved material characteristics. In this study, caffeic acid sulphonamide derivatives(CSs) were synthesised by conjugating sulphonamides to the backbone of caffeic acid. The structures of these derivatives were elucidated by means of Fourier transform infrared spectroscopy(FTIR), 1H NMR, 13C NMR, and electrospray ionization mass spectroscopy(ESI-MS). A content determination method was established by ultraviolet detection. The lipophilicity, 2,2-diphenyl-1-picrylhydrazy free radical(DPPH) scavenging capacity, anti-coagulant effects, anti-bacterial activity, cytotoxicity, in vitro anti-proliferative activity against tumour cells, and the ability of the compounds to promote the proliferation of chondrocytes were evaluated. The results indicate that CSs exhibit strong DPPH scavenging activity, high lipophilicity, good anti-coagulant activities, wide anti-bacterial activity range, low cytotoxicity, and an excellent ability to promote chondrocyte proliferation. 相似文献