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51.
Ouyang Jinbo Wang Yun Li Tianqi Zhou Limin Liu Zhirong 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(3):1419-1428
Journal of Radioanalytical and Nuclear Chemistry - The carboxyl-modified multiwalled carbon nanotubes were immobilized in chitosan-based composite membranes (CS-CNTs) which were used as efficient... 相似文献
52.
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
53.
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
54.
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
55.
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
56.
Lin Kaiwen Ming Shouli Chen Shuai Zhang Xiaobin Wang Ke Wang Yuehui Xu Jingkun 《Journal of Solid State Electrochemistry》2020,24(6):1387-1396
Journal of Solid State Electrochemistry - Electrochromic technologies require electrochromic π-conjugated polymers to reversibly transition between highly transmissive and broadly absorbing... 相似文献
57.
Optical bistability and multistability in a three-level Δ-type atomic system under the nonresonant condition 下载免费PDF全文
Under a nonresonant condition, we theoretically investigate hybrid
absorptive-dispersive optical bistability and multistability
behaviours in a three-level Δ-type system by using a microwave
field to drive a hyperfine transition between two upper excited
states inside a unidirectional ring cavity. We find that the optical
bistability and multistability behaviours can be controlled by
adjusting the intensity of the microwave field or the intensity of
the coherent coupling field. Furthermore, our studies show an
interesting phenomenon of the transition from the optical
bistability to the optical multistability only by changing the
negative detuning of the coupling field into the positive detuning
of the coupling field. 相似文献
58.
Estimating the distorted parameter in the case of non negative heavy-tailed losses has been treated in Brahimi et al. (2011). In this paper, we extend this work to the case of the real heavy-tailed losses. We derive an asymptotic distribution of the estimator. We construct a practically implemented confidence interval for the distortion parameter and illustrate the performance of the interval in a simulation study with application to real data. 相似文献
59.
Ultrasound (US) has become one of the most important techniques in green chemistry and emerging technologies. Many research investigations documented the usefulness of US in a wide range of applications in food science, nanotechnology, and complementary medicine, where effective extraction of natural products is important. However, as with all novel technologies, US has advantages and limitations that require clarification for full adaptation at an industrial scale. The present review discusses recent applications of US in herbal phytochemistry with the emphasis on US effects on chemical structures of bioactive compounds extracted from herbs and their bioactivities. The impact of different US processing conditions such as frequency, intensity, duration, temperature, and pressure on the effectiveness of the extraction process and the properties of the extracted materials are also discussed. Different frequencies and intensities of US have demonstrated its potential applications in modifying, determining, and predicting the physicochemical properties of herbs and their extracts. US has important applications in nanotechnology where it supports the fabrication of inexpensive and eco-friendly herbal nanostructures, as well as acoustic-based biosensors for chemical imaging of the herbal tissues. The application of US enhances the rates of chemical processes such as hydrolysis of herbal fibers, which reduces the time and energy consumed without affecting the quality of the final products. Overall, the use of US in herbal science has great potential to create novel chemical constructions and to be used as an innovative diagnostic system in various biomedical, food, and analytical applications. 相似文献
60.
核电池具有能量密度高、工作稳定可靠、无需人工干预等优点,在需要长期稳定供电的场合具有独特优势,其中热转换式核电池(RTG)是技术最为成熟且应用最早的一类,而β辐射伏特效应核电池已有商业化案例。目前,在β辐射伏特效应核电池研究中存在着放射源自吸收效应浪费能量、转化效率低、换能器件辐射损伤严重等问题,而对于一个实际的核电池,由于放射源自身不断衰变的属性,导致源的成分及其活度随着时间而发生变化,最终影响核电池的电学性能,其影响程度需要加以深入研究。本文以时间轴的形式对核电池的发展进行了全面回顾,简要介绍多种主流类型核电池的原理和应用范围;对于β辐射伏特效应核电池,指出放射源的自吸收是其中的关键科学问题。对于使用63Ni和TiT2放射源的核电池,给出了其电学性能随时间变化的规律;指出对于某一特定结构的β辐射伏特效应核电池设计,在前期的模拟优化环节中,精细计算是至关重要的;最后提出了将放射源与换能材料相结合、使用含有较重同位素的换能器件的设想,这些设想有利于解决放射源自吸收问题、提高核电池输出功率和减轻辐射损伤的影响。 相似文献