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21.
Liu Yuanyuan Zhou Weibo Liu Haiyan Wei Qianglin Gao Bai Chen Gongxin 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):33-42
Journal of Radioanalytical and Nuclear Chemistry - The concentrations of 238U, 226Ra, 232Th and 40K and gross α, β were measured in soils and sediments around a uranium tailings reservoir... 相似文献
22.
Chen Yujie Sang Weixuan Chen Rong Liu Xue Li Xiaoyan Guan Fenfen Li Xun Xiao Hui 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):367-373
Journal of Radioanalytical and Nuclear Chemistry - The nanoscale zero-valent nickel (nano-Ni0) was prepared by liquid-phase reduction method and characterized by BET, XPS, FT-IR and XRD and be used... 相似文献
23.
24.
A new polyoxygenated dihydropyrano[2,3-c]pyrrole-4,5-dione derivative, pyranonigrin F (1), together with a related known compound, pyranonigrin A (2), were isolated and identified from Penicillium brocae MA-231, an endophytic fungus obtained from the fresh tissue of the marine mangrove plant Avicennia marina. The structures of these metabolites were determined based on comprehensive spectral interpretation and the absolute configuration of compound 1 was established by X-ray crystallographic analysis. Compounds 1, and 2 showed potent activity against a broad spectrum of human-, aqua-, and plant-pathogens. 相似文献
25.
Czechoslovak Mathematical Journal - Let G = (VG,EG) be a graph and let NG[υ] denote the closed neighbourhood of a vertex υ in G. A function f: VG ? {?1,0,1} is said to be a... 相似文献
26.
Yang Shaoming Deng Kaiqiang Shao Shan Zhang Jian Peng Jiaxi Fang Zhili Xu Wenyuan 《Journal of Solid State Electrochemistry》2022,26(3):821-830
Journal of Solid State Electrochemistry - A molecularly imprinted photoelectrochemical (PEC) cathodic sensor was developed for the detection of bovine serum albumin (BSA). The PEC sensor was... 相似文献
27.
Ligand-promoted copper-catalyzed cascade reactions have become a robust tool for the synthesis of cyclic compounds. Although numerous ligands have been developed, this review focuses on the introduction of commercially available 1,10-phenanthroline-promoted copper-catalyzed cascade reactions in recent years. Moreover, based on original articles, this review highlights product yields in the presence and absence of the ligand, and the possible mechanistic role of the ‘copper/1,10-phenanthroline’ catalytic system. 相似文献
28.
We describe an effective and novel method to prepare N-aryl imidazoles via the copper quinolate-catalyzed N-arylation of aryl halides and imidazoles. A wide range of products were obtained in moderate to excellent yields under the optimal reaction conditions. Applying standard conditions, the model reaction could be performed on a gram scale. This method also presents a new avenue to the “click” reaction of terminal alkynes, benzyl bromide, and sodium azide and to the construction of C–C bonds by homocoupling of phenylboronic acid or phenylacetylene derivatives with the aid of copper quinolate. 相似文献
29.
Jia Mo Zhaofeng Ma Yixian Yang Xinxin Niu 《International Journal of Theoretical Physics》2013,52(11):3813-3819
This paper presents a Bell-dual-basis-based quantum watermarking protocol composed of three major algorithms: watermark embedding and extracting and the intercepting test. The first two are completed by using the entanglement swapping property of Bell dual basis and the test is accomplished through IBF protocol to guarantee its bottom security. The watermarking protocol is mainly designed for the protection of digital copyright in the existence of classical information. This design finds that the quality of digital contents is not damaged with its zero-watermark attributes when embedding watermarks. 相似文献
30.
Rigui Zhou Huian Wang Qian Wu Yang Shi 《International Journal of Theoretical Physics》2012,51(3):705-723
Based on analysis on properties of quantum linear superposition, to overcome the complexity of existing quantum associative
memory which was proposed by Ventura, a new storage method for multiply patterns is proposed in this paper by constructing
the quantum array with the binary decision diagrams. Also, the adoption of the nonlinear search algorithm increases the pattern
recalling speed of this model which has multiply patterns to O( log22n -t ) = O( n - t )O( {\log_{2}}^{2^{n -t}} ) = O( n - t ) time complexity, where n is the number of quantum bit and t is the quantum information of the t quantum bit. Results of case analysis show that the associative neural network model proposed in this paper based on quantum
learning is much better and optimized than other researchers’ counterparts both in terms of avoiding the additional qubits
or extraordinary initial operators, storing pattern and improving the recalling speed. 相似文献