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Bing Yang Yu Zhou Wenjie Yu Song Zhang Hongxiang Chen Ju Ye 《Polymer International》2019,68(4):675-683
In order to improve the dispersity and stability of the nano‐SiO2 aqueous system with high solid content, a kind of polyacrylic acid dispersant with methoxysilicon end groups (KH590‐PAA) was synthesized by photopolymerization of acrylic acid (AA) initiated with (3‐mercaptopropyl)trimethoxysilane (KH590). After adding KH590‐PAA into the nano‐SiO2 aqueous dispersion system (20 wt% solid content), the viscosity and the curing time of the system were measured with a rotational viscometer and the inverted bottle method. Moreover, the dispersion mechanism of KH590‐PAA for the nano‐SiO2 aqueous system was researched by measuring the adsorption capacity, the particle size and the zeta potential of the nanoparticles with a conductivity meter, dynamic light scattering, SEM and TEM, respectively. The results showed that the methoxysilicon groups in KH590‐PAA could react with hydroxyl groups on the surface of nano‐SiO2 in the process of stirring, which enhanced the adsorption capacity of the dispersant and then increased the surface charge of the particles. Therefore, electrostatic repulsion and steric hindrance effects between the SiO2 nanoparticles could be further enhanced by adding the KH590‐PAA dispersant, and then the nano‐SiO2 aqueous system exhibited better dispersity and stability. Besides, the dispersion properties of SiO2 nanoparticles in water were closely related to the addition amount and the molecular weight of the KH590‐PAA dispersant. © 2018 Society of Chemical Industry 相似文献
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Journal of Computer Science and Technology - DOACROSS loops are significant parts in many important scientific and engineering applications, which are generally exploited pipeline/wave-front... 相似文献
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Wu Ge Mu Yi Susilo Willy Guo Fuchun Zhang Futai 《International Journal of Information Security》2019,18(3):321-331
International Journal of Information Security - Data integrity is a critical security issue in cloud storage. The data integrity checking schemes by a third-party auditor (TPA) have attracted a lot... 相似文献
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Wei Lai Lihong Ge Huaming Li Yilin Deng Bin Xu Bo Ouyang Erjun Kan 《International Journal of Hydrogen Energy》2021,46(53):26861-26872
The electrochemical water splitting to produce H2 in high efficiency with earth-abundant-metal catalysts remains a challenge. Here, we describe a simple “cyclic voltammetry + ageing” protocol at room temperature to activate Ni electrode (AC-Ni/NF) for hydrogen evolution reaction (HER), by which Ni/Ni(OH)2 heterostructure is formed at the surface. In situ Raman spectroscopy reveals the gradual growth of Ni/Ni(OH)2 heterostructure during the first 30 min of the aging treatment and combined with polarization measurements, it suggests a positive relation between the Ni/Ni(OH)2 amount and HER performance of the electrode. The obtained AC-Ni/NF catalyst, with plentiful Ni–Ni(OH)2 interfaces, exhibits remarkable performance towards HER, with the low overpotential of only 30 mV at a H2-evolving current density of 10 mA/cm2 and 153 mV at 100 mA/cm2, as well as a small Tafel slope of 46.8 mV/dec in 1 M KOH electrolyte at ambient temperature. The excellent HER performance of the AC-Ni/NF could be maintained for at least 24 h without obvious decay. Ex situ experiments and in situ electrochemical-Raman spectroscopy along with density functional theory (DFT) calculations reveal that Ni/Ni(OH)2 heterostructure, although partially reduced, can still persist during HER catalysis and it is the Ni–Ni(OH)2 interface reducing the energy barrier of H1 adsorption thus promoting the HER performance. 相似文献
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Shibo Lv Yuyang Miao Dr. Dapeng Liu Prof. Fengling Song 《Chembiochem : a European journal of chemical biology》2020,21(15):2098-2110
Photothermal therapy (PTT) has attracted great attention due to its noninvasive and effective use against cancer. Various photothermal agents (PTAs) including organic and inorganic PTAs have been developed in the last decades. Organic PTAs based on small-molecule dyes exhibit great potential for future clinical applications considering their good biocompatibility and easy chemical modification or functionalization. In this review, we discuss the recent progress of organic PTAs based on small-molecule dyes for enhanced PTT. We summarize the strategies to improve the light penetration of PTAs, methods to enhance their photothermal conversion efficiency, how to optimize PTAs’ delivery into deep tumors, and how to resist photobleaching under repeated laser irradiation. We hope that this review can rouse the interest of researchers in the field of PTAs based on small-molecule dyes and help them to fabricate next-generation PTAs for noninvasive cancer therapy. 相似文献
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