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991.
Yayang Wang Xiaojie Yang Jiahui Lou Yaqiong Huang Jian Peng Yuesheng Li Yi Liu 《Molecules (Basel, Switzerland)》2022,27(23)
Environmental pollution, especially water pollution, is becoming increasingly serious. Organic dyes are one type of the harmful pollutants that pollute groundwater and destroy ecosystems. In this work, a series of graphitic carbon nitride (g-C3N4)/ZnO photocatalysts were facilely synthesized through a grinding method using ZnO nanoparticles and g-C3N4 as the starting materials. According to the results, the photocatalytic performance of 10 wt.% CN-200/Z-500 (CN-200, which g-C3N4 was 200 kGy, referred to the irradiation metering. Z-500, which ZnO was 500 °C, referred to the calcination temperature) with the CN-200 exposed to electron beam radiation was better than those of either Z-500 or CN-200 alone. This material displayed a 98.9% degradation rate of MB (20 mg/L) in 120 min. The improvement of the photocatalytic performance of the 10 wt.% CN-200/Z-500 composite material was caused by the improvement of the separation efficiency of photoinduced electron–hole pairs, which was, in turn, due to the formation of heterojunctions between CN-200 and Z-500 interfaces. Thus, this study proposes the application of electron-beam irradiation technology for the modification of photocatalytic materials and the improvement of photocatalytic performance. 相似文献
992.
Yinping Qin Hefeng Wang Jingjing Zhou Ruyi Li Chun Jiang Yi Wan Xiaoyi Wang Zhenlian Chen Xiaolei Wang Yang Liu Bingkun Guo Deyu Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(19):e202402456
The solid electrolyte interphase (SEI) membrane on the Li metal anode tends to breakdown and undergo reconstruction during operation, causing Li metal batteries to experience accelerated decay. Notably, an SEI membrane with self-healing characteristics can help considerably in stabilizing the Li-electrolyte interface; however, uniformly fixing the repairing agent onto the anode remains a challenging task. By leveraging the noteworthy film-forming attributes of bis(fluorosulfonyl)imide (FSI−) anions and the photopolymerization property of the vinyl group, the ionic liquid 1-vinyl-3-methylimidazolium bis(fluorosulfonyl)imide (VMI-FSI) was crosslinked with polyethylene oxide (PEO) in this study to form a self-healing film fixing FSI− groups as the repairing agent. When they encounter lithium metal, the FSI− groups are chemically decomposed into LiF & Li3N, which assist forming SEI membrane on lithium sheet and repairing SEI membrane in the cracks lacerated by lithium dendrite. Furthermore, the FSI− anions exchanged from film are electrochemically decomposed to generate inorganic salts to strengthen the SEI membrane. Benefiting from the self-healing behavior of the film, Li/LiCoO2 cells with the loading of 16.3 mg cm−2 exhibit the initial discharge capacities of 183.0 mAh ⋅ g−1 and are stably operated for 500 cycles with the retention rates of 81.4 % and the average coulombic efficiency of 99.97 %, operated between 3.0–4.5 V vs. Li+/Li. This study presents a new design approach for self-healing Li metal anodes and durable lithium metal battery. 相似文献
993.
994.
995.
Zhen Zhou Hong Ren Lei Zhou Peng Wang Xiaoming Lou Hua Zou Yiyao Cao 《Molecules (Basel, Switzerland)》2023,28(1)
In the context of the rapid development of the world’s nuclear power industry, it is vital to establish reliable and efficient radioanalytical methods to support sound environment and food radioactivity monitoring programs and a cost-effective waste management strategy. As one of the most import fission products generated during human nuclear activities, 90Sr has been widely determined based on different analytical techniques for routine radioactivity monitoring, emergency preparedness and radioactive waste management. Herein, we summarize and critically review analytical methods developed over the last few decades for the determination of 90Sr in environmental and biological samples. Approaches applied in different steps of the analysis including sample preparation, chemical separation and detection are systematically discussed. The recent development of modern materials for 90Sr concentration and advanced instruments for rapid 90Sr measurement are also addressed. 相似文献
996.
Hao-Fei Ni Lou-Kai Ye Peng-Cheng Zhuge Bo-Lan Hu Jia-Rui Lou Chang-Yuan Su Zhi-Xu Zhang Li-Yan Xie Da-Wei Fu Yi Zhang 《Chemical science》2023,14(7):1781
Organic–inorganic halide perovskites (OIHPs) are very eye-catching due to their chemical tunability and rich physical properties such as ferroelectricity, magnetism, photovoltaic properties and photoluminescence. However, no nickel-based OIHP ferroelectrics have been reported so far. Here, we designed an ABX3 OIHP ferroelectric (3-pyrrolinium)NiCl3, where the 3-pyrrolinium cations are located on the voids surrounded by one-dimensional chains composed of NiCl6-face-sharing octahedra via hydrogen bonding interactions. Such a unique structure enables the (3-pyrrolinium)NiCl3 with a high spontaneous polarization (Ps) of 5.8 μC cm−2 and a high Curie temperature (Tc) of 428 K, realizing dramatic enhancement of 112 and 52 K compared to its isostructural (3-pyrrolinium)MCl3 (M = Cd, Mn). To our knowledge, remarkably, (3-pyrrolinium)NiCl3 should be the first case of nickel(ii)-based OIHP ferroelectric to date, and its Tc of 428 K (35 K above that of BaTiO3) is the highest among all reported one-dimensional OIHP ferroelectrics. This work offers a new structural building block for enriching the family of OIHP structures and will inspire the further exploration of new nickel(ii)-based OIHP ferroelectrics.Organic–inorganic halide perovskites (OIHPs) are very eye-catching due to their chemical tunability and rich physical properties such as ferroelectricity, magnetism, photovoltaic properties and photoluminescence. 相似文献
997.
998.
Improved all-optical OR gates are proposed, using a novel fiber nonlinearity-based technique, based on the principles of combined Brillouin gain and loss in a polarization-maintaining fiber (PMF). Switching contrasts are simulated to be between 82.4%-83.6%, for two respective configurations, and switching time is comparable to the phonon relaxation time in stimulated Brillouin scattering (SBS). 相似文献
999.
We study the swelling of a gel annulus attached to a rigid core when it is immersed in a solvent.For equilibrium states,the free-energy function of the gel can be converted into a strain energy function,and as a result the gel can be treated as a compressible hyperelastic material.Asymptotic methods are used to study the inhomogeneous swelling in order to obtain the leading-order solution.Some analytical insights are then deduced.Because of the compressive hoop stress in this state,at some stage instability can occur,leading to wrinkles in the gel.An incremental deformation theory in nonlinear elasticity is used to conduct a linear bifurcation analysis for understanding such instability.More specifically,the critical loading for the onset of a wrinkled state is obtained.Detailed discussions on the behaviors of various physical quantities in this critical state are given.It is found that the critical mode number,while insensitive to the material parameters,is greatly influenced by the ratio of the inner and outer radii of the gel.Also,an interesting finding is that the critical swelling ratio is an increasing function of this geometrical parameter,which implies that a thin annulus is more likely to be unstable than a thick one. 相似文献
1000.