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981.
Janus 粒子,也称为阴阳结构粒子或两面性非对称粒子,是指表面上具有两种或两种以上不同化学组成或性质的不对称粒子。目前,Janus 粒子因其独特的结构和功能已经逐渐成为生物医药、催化、材料以及防污等领域中的新型功能材料。在环境检测领域,Janus材料亦因其特殊的光学、磁学及电学性能,为提高检测灵敏度、选择性和稳定性等提供了新的研究方向。基于此,本文主要讨论了Janus材料在环境检测方面的特点、优势和相关应用。最后,本文基于本课题组的研究经验以及工作中所面临的问题,对本领域的发展和未来的研究方向提出了展望,以期对本领域的未来发展提供指导。 相似文献
982.
983.
纸基生物传感器由于其具有成本低、操作方便、生物可降解、识别元件用量低等优点,近年来受到了广泛的关注。其中,以功能核酸作为识别元件的纸基荧光生物传感器具有较高的灵敏度、瞬时响应以及实时检测等特性,在便携式传感设备方面展现出巨大的潜力。此外,将核酸作为识别元件的纸基无细胞蛋白合成平台,通过条件合成的报告荧光蛋白可实现对病毒、重金属等目标物的特异性检测,具有良好的应用前景。首先,本文介绍了基于核酸的纸基荧光生物传感器的设计,特别是基于核酸的识别元件与纸基材料的结合方式。其次,总结了基于核酸的纸基荧光生物传感器在临床诊断、食品安全检测、环境污染物检测等不同领域的最新研究进展,讨论了其优势与局限性。最后,探讨了基于核酸的纸基荧光生物传感器的发展方向与应用前景,以期为相关领域的研究提供参考。 相似文献
984.
Mechanistic studies promote scientific development from phenomena to theories.Aggregation-induced emission(AIE),as an unusual photophysical phenomenon,builds the bridge between molecular science and aggregate mesoscience.With the twenty-year development of AIE,restriction of intramolecular motion(RIM)has been verified as the working mechanism of AIE effect.In this review,these mechanistic works about RIM are summarized from experimental and theoretical perspectives.Thereinto,the experimental studies are introduced from three parts:external rigidification,structural modification and structural characterization.In the theoretical part,calculations on the low-frequency motion of AIEgens have been performed to prove the RIM mechanism.By virtue of the theoretical calculations,some new mechanisms are proposed to supplement the RIM,such as restriction of access to conical intersection,suppression of Kasha transition,restriction of access to dark state,etc.It is foreseeable that the RIM mechanism will unify the photophysical theories for both molecules and aggregates,and inspire more progress in aggregate science. 相似文献
985.
Hua Lei Meixuan Wu Ying Liu Fan Mo Jiayao Chen Shilong Ji Yan Zou Xiaoping Dong 《中国化学快报》2021,32(7):2317-2321
Photocatalysis technology has been proved to be a potential strategy for removal of organic dyes, however high-power light sources are generally necessary to initiate photocatalytic reaction. In this work, we employed an excellent photocatalyst of Bi2WO6 with visible light harvest and meanwhile an intrinsic ferroelectricity, which realized the efficient degradation of organic dye via the synergetic photopiezocatalysis. Through coupling the illumination by a low-power (9 W) LED and the ultrasonic vibration (120 W) by an ultrasonic cleaner, the nanoflower-like Bi2WO6 composed of ultrathin nanosheets showed a much more enhanced photopiezocatalysis performance for purification of organic dye than the individual photocatalysis and piezocatalysis. Furthermore, the high mineralization efficiency and the good durability of the Bi2WO6 catalyst were demonstrated. The possible mechanism of photopiezocatalysis was finally proposed, where the ultrasound-induced piezoelectric field in Bi2WO6 drove photo-generated electrons and holes to diffuse along opposite directions, consequently promoting the separation efficiency of charge carriers. This work indicates that the synergetic photopiezocatalysis by coupling irradiation and ultrasonic vibration is a promising strategy to purify organic pollutants in wastewater. 相似文献
986.
987.
988.
Lingli Lei Yuanyuan Zhang Ying Jiang Lulu Xiong Yingshuai Liu Chang Ming Li 《Electroanalysis》2021,33(10):2180-2186
Biomimetic electrochemical sensors are very promising not only due to their lower expense and longer stability than conventional enzymatic ones, but they also often suffer from simultaneously achieving high sensitivity and good selectivity. Here we present a well-defined Au@Co3O4/CeO2 yolk-shell nanostructure (YSN) that is first synthesized and exploited as highly efficient electrocatalysts for hydrogen peroxide (H2O2) detection. The introduced CeO2 in Co3O4 matrix greatly facilitates the migration of lattice oxygen, which increases the concentration of surface oxygen vacancies (Oa), remarkably enhancing the adsorption ability of H2O2 and promoting the decomposition of H2O2 for faster electron transfer than pristine Au@Co3O4 core-shell nanostructure (CSN). The abundant Oa of Au@Co3O4/CeO2 YSN is confirmed by X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR). The as-prepared biomimetic sensor delivers a wide dynamic range (5.0 nM to 5.4 μM), a low limit of detection (LOD) (2.74 nM), and a high sensitivity (35.67 μA μM−1 cm−2), paving a new way to construct an ultrasensitive and selective enzyme-free biomimetic electrochemical sensor. Furthermore, the sensor is used to real-time monitor H2O2 released from human cervical cancer cells (HeLa) and human umbilical vein endothelial cells (HUVEC), demonstrating its great potential in practical applications. 相似文献
989.
Xiaoya Wang Bingbing Liu Jie Li Yunyun Zhai Haiqing Liu Lei Li Herui Wen 《Electroanalysis》2021,33(6):1484-1490
2D metal-organic framework (MOF) has potential applications in electrocatalysis owing to fast mass transfer, charge transfer and large specific surface area. Here, we had prepared three conductive 2D MOF based on Ni, NiCo and Co in a simple and rapid way. The 2D nanostructure of MOF was confirmed by SEM and TEM. The chemical composition was studied by XRD, Raman and XPS spectrum. The electrochemical oxidation and detection was investigated through cyclic voltammetry and current-time method. Their sensing performance for urea was determined by varying oxidation potentials and metal sites. The non-enzymatic Ni-, NiCo- and Co-MOF sensors had good catalytic activity for urea. Compared with NiCo- and Co-MOF, Ni-MOF had a wider linear range (0.5–832.5 μM), high sensitivity (1960 μA mM−1 cm−2), low detection limit (0.471 μM), and fast response time. The sensors had well repeatability, reproducibility, and selectivity to specific interfering species. Furthermore, Ni- and NiCo-MOF modified electrode was also applied to detection of milk samples. The results showed that the recovery was satisfactory, which further confirmed the effectiveness of non-enzyme sensor. In general, the highly-sensitive 2D Ni- and NiCo-MOF modified electrode has great potential as nonenzymatic urea sensors for real samples detection in hydrogen energy, clinical diagnostics, and environmental protection, et al. 相似文献
990.
Hao Xu Jie Zhu Xiong Wang Chao Shen Shengshen Meng Kai Zheng Chao Lei Longfeng Zhu 《Molecules (Basel, Switzerland)》2021,26(5)
Developing sustainable routes for the synthesis of zeolites is still a vital and challenging task in zeolite scientific community. One of the typical examples is sustainable synthesis of aluminosilicate EU-1 zeolite, which is not very efficient and environmental-unfriendly under hydrothermal condition due to the use of a large amount of water as solvent. Herein, we report a sustainable synthesis route for aluminosilicate EU-1 zeolite without the use of solvent for the first time. The physicochemical properties of the obtained EU-1 zeolite are characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry-differential thermal analysis (TG-DTA), N2 sorption, inductively coupled plasma (ICP) analysis, and solid nuclear magnetic resonance (NMR), which show the product has high crystallinity, uniform morphology, large BET surface area, and four-coordinated aluminum species. Moreover, the impact of synthesis conditions is investigated in detail. The sustainable synthesis of aluminosilicate EU-1 zeolite under solvent-free 相似文献