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91.
Li Qiu WANG Xiao Jun PENG* Rong ZHANG Guo Quan XU Jing Nan CUI State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 《中国化学快报》2003,(1)
Indocyanine dyes as fluorescent labeling reagents have been used in bioanalysis1,2. Arylsulfonate indocyanine dyes 1d and 1e developed by Waggoner A. S. et al.3,4 have excellent fluorescent properties combined with good aqueous solubility, are a new generation of fluorescent label compounds for proteins, oligonucleotides and other compounds containing hydroxyl, mercaptol or primary amine groups5. However, photostability of these dyes has been a problem. Z. G. YAO et al.6 reported that p… 相似文献
92.
93.
94.
BaCe0.8Pr0.2O3-α ceramic was synthesized by high temperature solid-state reaction. The structural characteristics and the phase purity of the crystal were determined using powder X-ray diffraction analysis. By using the methods of AC impedance spectroscopy, gas concentration cell and electrochemical pumping of hydrogen, the conductivity and ionic transport number of BaCe0.8Pr0.2O3-α were measured, and the electrical conduction behavior of the material was investigated in different gases in the temperature range of 500-900 ffiC. The results indicate that the material was of a single perovskite-type orthorhombic phase. From 500 ffiC to 900 ffiC, electronic-hole conduction was dominant in dry and wet oxygen, air or nitrogen, and the total conductivity of the material increased slightly with increasing oxygen partial pressure in the oxygen partial pressure range studied. Ionic conduction was dominant in wet hydrogen, and the total conductivity was about one or two orders of magnitude higher than that in hydrogen-free atmosphere (oxygen, air or nitrogen). 相似文献
95.
He Liu Mengnan An Hongyang Si Yuhang Shan Chuantao Xu Gang Hu Yunbo Xie Dongyang Liu Shujun Li Rui Qiu Chong Zhang Yuanhua Wu 《Molecules (Basel, Switzerland)》2022,27(17)
As an important microbial resource, Actinomycetes, especially Streptomyces, have important application values in medicine and biotechnology. Streptomyces fungicidicus SYH3 was isolated from soil samples in tomato-growing areas and showed good inhibitory effects on Alternaria solani in tomato. To obtain pure active compounds, SYH3 fermentation broth was subjected to XAD-16 macroporous resin and silica gel column chromatography. Combined with the repeated preparation and separation of preparative high-performance liquid chromatography (HPLC), a total of four monomer compounds were obtained after activity tracking. Compound 4 was identified as a new six-membered lactone ring compound named 6-(5-hydroxy-6-methylheptyl)-5,6-dihydro-2H-pyran-2-one by 1D and 2D nuclear magnetic resonance (NMR) data and mass spectrometry (MS). The other three active compounds belong to the cyclodipeptide, and their half maximal inhibitory concentration (IC50) values against A. solani were 43.4, 42.9, and 30.6 μg/mL, respectively. Compound 4 significantly inhibited the spore germination and induced swollen and deformed local hyphae of A. solani with an IC50 value of 24.9 μg/mL. Compound 4 also had broad-spectrum antifungal activity and had a good antifungal effect on the tested plant-pathogenic fungi. The modes of action of new compound (4) still require further investigation, representing a novel and effective anti-fungal agent for future application. 相似文献
96.
Mingyue Qiu Haonan Wu Yi Huang Huijuan Guo Dan Gao Feng Pei Lijuan Shi Qun Yi 《Molecules (Basel, Switzerland)》2022,27(18)
The design of high-efficiency CO2 adsorbents with low cost, high capacity, and easy desorption is of high significance for reducing carbon emissions, which yet remains a great challenge. This work proposes a facile construction strategy of amino-functional dynamic covalent materials for effective CO2 capture from flue gas. Upon the dynamic imine assembly of N-site rich motif and aldehyde-based spacers, nanospheres and hollow nanotubes with spongy pores were constructed spontaneously at room temperature. A commercial amino-functional molecule tetraethylenepentamine could be facilely introduced into the dynamic covalent materials by virtue of the dynamic nature of imine assembly, thus inducing a high CO2 capacity (1.27 mmol·g−1) from simulated flue gas at 75 °C. This dynamic imine assembly strategy endowed the dynamic covalent materials with facile preparation, low cost, excellent CO2 capacity, and outstanding cyclic stability, providing a mild and controllable approach for the development of competitive CO2 adsorbents. 相似文献
97.
Lingyun Lou Tianqi Xu Yuzhan Li Changli Zhang Bochun Wang Xusheng Zhang Hean Zhang Yuting Qiu Junyan Yang Dong Wang Hui Cao Wanli He Zhou Yang 《Molecules (Basel, Switzerland)》2022,27(19)
Pure organic room-temperature phosphorescence (RTP) materials built upon noncovalent interactions have attracted much attention because of their high efficiency, long lifetime, and stimulus-responsive behavior. However, there are limited reports of noncovalent RTP materials because of the lack of specific design principles and clear mechanisms. Here, we report on a noncovalent material prepared via facile grinding that can emit fluorescence and RTP emission differing from their components’ photoluminescent behavior. Exciplex can be formed during the preparation process to act as the minimum emission unit. We found that H-bonds in the RTP system provide restriction to nonradiative transition but also enhance energy transformation and energy level degeneracy in the system. Moreover, water-stimulated photoluminescent ink is produced from the materials to achieve double-encryption application with good resolution. 相似文献
98.
Yiting Zheng Yuen Tsz Cheung Lixin Liang Huiying Qiu Lei Zhang Anson Tsang Qing Chen Rongbiao Tong 《Chemical science》2022,13(35):10479
Oxidative rearrangement of tetrahydro-β-carbolines (THβCs) is one of the most efficient methods for the synthesis of biologically active spirooxindoles, including natural products and drug molecules. Here, we report the first electrochemical approach to achieve this important organic transformation in a flow cell. The key to the high efficiency was the use of a multifunctional LiBr electrolyte, where the bromide (Br−) ion acts as a mediator and catalyst and lithium ion (Li+) acts as a likely hydrophilic spectator, which might considerably reduce diffusion of THβCs into the double layer and thus prevent possible nonselective electrode oxidation of indoles. Additionally, we build a zero-gap flow cell to speed up mass transport and minimize concentration polarization, simultaneously achieving a high faradaic efficiency (FE) of 96% and an outstanding productivity of 0.144 mmol (h−1 cm−2). This electrochemical method is demonstrated with twenty substrates, offering a general, green path towards bioactive spirooxindoles without using hazardous oxidants.A zero-gap flow cell was designed for the first electro-oxidative rearrangement of tetrahydro-β-carbolines to spirooxindoles with high yield, faradaic efficiency and productivity when LiBr was discovered as a bi-functional mediator and catalyst. 相似文献
99.
Jianmei Liu Hong Wang Zhi Ma Qianheng Duan Yangyang Fei Xiangdong Meng 《Entropy (Basel, Switzerland)》2022,24(7)
In this paper, we consider the optimization of the quantum circuit for discrete logarithm of binary elliptic curves under a constrained connectivity, focusing on the resource expenditure and the optimal design for quantum operations such as the addition, binary shift, multiplication, squaring, inversion, and division included in the point addition on binary elliptic curves. Based on the space-efficient quantum Karatsuba multiplication, the number of CNOTs in the circuits of inversion and division has been reduced with the help of the Steiner tree problem reduction. The optimized size of the CNOTs is related to the minimum degree of the connected graph. 相似文献
100.
In this paper,the symplectic perturbation series methodology of the non-conservative linear Hamiltonian system is presented for the structural dynamic response ... 相似文献