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81.
Changshi Yu Yunhua Xu Shijie Liang Xudong Jiang Guitao Feng Cheng Li Weiwei Li 《中国化学快报》2018,29(2):325-327
Star-shaped electron acceptors based on perylene bisimide as end groups and spiro-aromatic core linked with ethynyl units were developed for nonfullerene solar cells. Ethynyl linkers are able to improve the planarity of conjugated backbone, resulting in enhanced electron mobility and power conversion efficiency in solar cells. 相似文献
82.
Phosphoric Acid Catalyzed Asymmetric [2+2] Cyclization/Penicillin–Penillonic Acid Rearrangement 下载免费PDF全文
Ming Zhang Changjun Yu Dr. Junqiu Xie Xudong Xun Dr. Wangsheng Sun Prof. Dr. Liang Hong Prof. Dr. Rui Wang 《Angewandte Chemie (International ed. in English)》2018,57(18):4921-4925
Enantioselective synthesis of imidazolidin‐5‐ones through a phosphoric acid catalyzed reaction between azlactones and N‐substituted β‐carbolines is reported. The reaction takes place via an initial formal [2+2] cycloaddition to generate an α‐amino‐β‐lactam, which subsequently undergoes an acid‐catalyzed asymmetric penicillin–penillonic acid (PPA) rearrangement with high diastereo‐ and enantioselectivity. To the best of our knowledge, this represents the first [2+2] cyclization of azlactones with imines and the first asymmetric PPA rearrangement, which are linked together by the phosphoric acid catalyst. 相似文献
83.
Dr. Tingting Xu Dr. Xudong Hou Dr. Yi Han Dr. Haipeng Wei Dr. Zhengtao Li Prof. Dr. Chunyan Chi 《Angewandte Chemie (International ed. in English)》2023,62(38):e202304937
Polycyclic hydrocarbons consisting of two or more directly fused antiaromatic subunits are rare due to their high reactivity. However, it is important to understand how the interactions between the antiaromatic subunits influence the electronic properties of the fused structure. Herein, we present the synthesis of two fused indacene dimer isomers: s-indaceno[2,1-a]-s-indacene ( s -ID ) and as-indaceno[3,2-b]-as-indacene ( as -ID ), containing two fused antiaromatic s-indacene or as-indacene units, respectively. Their structures were confirmed by X-ray crystallographic analysis. 1H NMR/ESR measurements and DFT calculations revealed that both s -ID and as -ID have an open-shell singlet ground state. However, while localized antiaromaticity was observed in s -ID , as -ID showed weak global aromaticity. Moreover, as -ID exhibited a larger diradical character and a smaller singlet-triplet gap than s -ID . All the differences can be attributed to their distinct quinoidal substructures. 相似文献
84.
Jing B Chen X Zhao Y Wang X Cai J Qiu H 《The journal of physical chemistry. B》2008,112(24):7191-7195
The supramolecular ionic self-assembly (ISA) strategy has been used to construct the long-range ordered hierarchical aggregates from the complexes of 1-adamantanamine hydrochloride (AdCl) and sodium bis(2-ethyl-1-hexyl)sulfosuccinate (AOT). The formed AOT-Ad complexes have been proved to possess a composition of equal molar ratio and a hexagonal columnar structure with Ad blocks as the core and AOT outside. More interestingly, the length, width, and thickness of the aggregates are on the order of milli-, micro-, and nanometer, respectively, and can thus be taken as one type of organic nanobelt. Such nanobelts are plastic and stable to resist breakage even bent to a circle, which makes them useful in the fields of novel nanomaterial fabrication. In addition, the ISA process of this aggregate can be tuned by including Ad blocks in beta-cyclodextrins to form a supramolecular complex, which is comparatively stable in the water and expected to self-assemble into some other ordered structures. 相似文献
85.
Tong Shen Dr. Ya Zou Dr. Xudong Hou Dr. Haipeng Wei Dr. Longbin Ren Liuying Jiao Prof. Jishan Wu 《Angewandte Chemie (International ed. in English)》2023,62(45):e202311928
Polycyclic aromatic hydrocarbons (PAHs) with a one-dimensional (1D), ribbon-like structure have the potential to serve as both model compounds for corresponding graphene nanoribbons (GNRs) and as materials for optoelectronics applications. However, synthesizing molecules of this type with extended π-conjugation presents a significant challenge. In this study, we present a straightforward synthetic method for a series of bis-peri-dinaphtho-rylene molecules, wherein the peri-positions of perylene, quaterrylene, and hexarylene are fused with naphtho-units. These molecules were efficiently synthesized primarily through intramolecular or intermolecular radical coupling of in situ generated organic radical species. Their structures were confirmed using X-ray crystallographic analysis, which also revealed a slightly bent geometry due to the incorporation of a cyclopentadiene ring at the bay regions of the rylene backbones. Bond lengh analysis and theoretical calculations indicate that their electronic structures resemble pyrenacenes more than quinoidal rylenes. That is, the aromatic sextets are predominantly localized along the long axis of the skeletones. As the chain length increases, these molecules exhibit enhanced electronic absorption with a bathochromic shift, and multiple amphoteric redox waves. This study introduces a novel synthetic approach for generating 1D extended PAHs and GNRs, along with their structure-dependent electronic properties. 相似文献
86.
We have demonstrated sensitive label-free virus detection using the opto-fluidic ring resonator (OFRR) sensor. The OFRR is a novel sensing platform that integrates the microfluidics and photonic sensing technology with a low detection limit and small volume. In our experiment, filamentous bacteriophage M13 was used as a safe model system. Virus samples were flowed through the OFRR whose surface was coated with M13-specific antibodies. We studied the sensor performance by monitoring in real-time the virus and antibody interaction. It is shown that OFRR can detect M13 with high specificity and sensitivity. The detection limit is approximately 2.3 x 10(3) pfu mL(-1) and the detection dynamic range spanned seven orders of magnitude. Theoretical analysis was also carried out to confirm the experimental results. Our study will lead to development of novel OFRR-based, sensitive, rapid, and low-cost micro total analysis devices for virus detection. 相似文献
87.
88.
Identification of chemical constituents in traditional Chinese medicine formula using HPLC coupled with linear ion trap‐Orbitrap MS from high doses of medicinal materials to equivalent doses of formula: Study on Xiang‐Sha‐Liu‐Jun‐Zi‐Jia‐Jian granules 下载免费PDF全文
Zhiwei Lu Qing Wang Meiling Wang Yuehong Liu Shuang Fu Xiaoyan Gao Xudong Tang 《Journal of separation science》2016,39(9):1619-1627
High‐resolution mass spectrometry has been a powerful tool for the research of chemical constituents in traditional Chinese medicine (TCM) formulas. However, the chromatographic peaks were difficult to discriminate clearly in data collection or analysis because of the complexity and the greatly different content of the constituents in TCM formula, which increased the difficulty of identification. In this study, a high‐performance liquid chromatography coupled with linear ion trap‐Orbitrap mass spectrometry based strategy focused on the comprehensive identification of TCM formula constituents was developed. Identification was carried out from a high dose of medicinal materials to equivalent dose of formula. Meanwhile, combined with mass spectrometry data, chromatographic behaviors, reference standards and previous reports, the identification of constituents in Xiang‐Sha‐Liu‐Jun‐Zi‐Jia‐Jian granules was described. 169 compounds were unambiguously or tentatively characterized, mainly including flavonoids, alkaloids, triterpenic acids, triterpene saponins, lactones, sesquiterpenoids and some other compounds. Among them, 11 compounds were unambiguously confirmed by comparing with reference standards. These results demonstrated that the method was effective and reliable for comprehensive identification of constituents of Xiang‐Sha‐Liu‐Jun‐Zi‐Jia‐Jian granules extracts and reveal the material basis of its therapeutic effects. This strategy might propose a research idea for the characterization of multi‐constituents in TCM formula. 相似文献
89.
Xinghao Lin Youzhong Dong Quan Kuang Danlin Yan Xudong Liu Wei Han Yanming Zhao 《Journal of Solid State Electrochemistry》2016,20(5):1241-1250
A new Co-base sodium metaphosphate compound, NaCo(PO3)3, has been synthesized here by solid-state method. The crystal structure is refined by the Rietveld method, and the results reveal that NaCo(PO3)3 has an orthorhombic structure with the space group of P2 1 2 1 2 1 and lattice parameters of a = 14.2453(2) Å, b = 14.2306(1) Å, and c = 14.2603(2) Å. Its typical morphology and chemical composition are confirmed by scanning electron microscopy (SEM) and energy-dispersive spectrometry (EDS). The valence states of all elements and the internal/external vibrational modes of NaCoP3O9 compound are measured by X-ray photoelectron and vibrational spectrum, where a typical feature of the (PO3)? polyanion group is observed. Meanwhile, the electrochemical properties of NaCo(PO3)3 cathode for sodium-ion batteries are also elevated and an initial discharge capacity of 33.8 mAh/g can be obtained at 0.05 C within 1.5–4.2 V. After 20 cycles, a discharge capacity of 26.7 mAh/g can be obtained and a well-kept oxidation–reduction plateau is still observed for NaCo(PO3)3 cathode, indicating the good reversibility of this metaphosphate electrode. 相似文献
90.
Superior Electrical Conductivity in Hydrogenated Layered Ternary Chalcogenide Nanosheets for Flexible All‐Solid‐State Supercapacitors 下载免费PDF全文
Dr. Xin Hu Wei Shao Xudong Hang Dr. Xiaodong Zhang Prof. Wenguang Zhu Prof. Yi Xie 《Angewandte Chemie (International ed. in English)》2016,55(19):5733-5738
As the properties of ultrathin two‐dimensional (2D) crystals are strongly related to their electronic structures, more and more attempts were carried out to tune their electronic structures to meet the high standards for the construction of next‐generation smart electronics. Herein, for the first time, we show that the conductive nature of layered ternary chalcogenide with formula of Cu2WS4 can be switched from semiconducting to metallic by hydrogen incorporation, accompanied by a high increase in electrical conductivity. In detail, the room‐temperature electrical conductivity of hydrogenated‐Cu2WS4 nanosheet film was almost 1010 times higher than that of pristine bulk sample with a value of about 2.9×104 S m?1, which is among the best values for conductive 2D nanosheets. In addition, the metallicity in the hydrogenated‐Cu2WS4 is robust and can be retained under high‐temperature treatment. The fabricated all‐solid‐state flexible supercapacitor based on the hydrogenated‐Cu2WS4 nanosheet film shows promising electrochemical performances with capacitance of 583.3 F cm?3 at a current density of 0.31 A cm?3. This work not only offers a prototype material for the study of electronic structure regulation in 2D crystals, but also paves the way in searching for highly conductive electrodes. 相似文献