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992.
为实现污泥雾化破碎的数值模拟,探究污泥雾化特征和操作参数对污泥雾化效果的影响,在污泥雾化试验平台试验的基础上基于Fluent软件对污泥在气体辅助式雾化器的雾化破碎进行模拟研究,模拟结果确定了污泥的雾化特征和最优操作参数。通过耦合流体体积法(VOF)与离散相模型(DPM),对较大的液体团采用VOF方法直接求解,对小液滴采用双向耦合的离散相模型进行追踪,能最大程度地提高计算的准确性。结果表明,污泥的密度和黏度随着含水率升高逐渐降低,气体速度、气液比和雾化角度是影响污泥雾化破碎的最重要的三个操作参数。在雾化过程中,中心区域的雾滴密度大于边缘区域且有少量大颗粒的聚集。对于含水率为87%、密度为1.065×103 kg/m3的污泥,在风速为180 m/s,气液比为126.3,雾化角度为55°时雾化效果最佳,雾滴颗粒的平均粒径约为0.193 mm,试验结果与模拟结果的颗粒粒径吻合度较好,最大相对误差为5.80%。 相似文献
993.
Zhang Yu Dong Yi Zou Renzhi Zhou Zhiying Hu Wenshuo Ran Mingchu Song Hao Liu Shaojun Zheng Chenghang Gao Xiang 《Catalysis Letters》2022,152(4):1140-1144
Catalysis Letters - Investigation of the low-temperature (LT) selective catalytic reduction (SCR) of NOx has adsorbed extensive efforts, and is now a hot topic in environmental catalysis. In this... 相似文献
994.
Zhou Jianping Pei Ziyuan Li Nan Han Shitong Li Yongpeng Chen Qi Sui Zhuyin 《Journal of Porous Materials》2022,29(4):983-990
Journal of Porous Materials - In this work, a three-dimensional (3D) graphene/manganese dioxide nanocomposite (PGA/MnO2) with a hierarchically porous structure was prepared by facile steam... 相似文献
995.
Chaoqun Xia Shi Liu Baining Cui Mingjun Li Hongshui Wang Chunyong Liang Phong A. Tran Yan Wang Huan Zhou Lei Yang 《International Journal of Applied Ceramic Technology》2022,19(5):2437-2449
Development of reliable ultraviolet (UV) blockers is crucial for UV radiation protection applications such as sunscreen and UV-resistant fabric. To date, zinc oxide (ZnO) has been extensively used as a physical UV blocker worldwide but has also been criticized for with its unfavored UV-induced reactive oxygen species (ROS) generation phenomena. As an attempt to suppress the photocatalytic activity of ZnO without compromising its UV absorbance property, amorphous selenium (Se) nanoparticles (NPs) were incorporated to ZnO using a facile and cost-effective coprecipitation method. Additionally, this process also enables an economical synthesis route for harvesting amorphous Se NPs from an aqueous medium. The ZnO–Se composites were thoroughly characterized to confirm its enhanced UV absorptivity combined with high transparency in the visible light range and to understand the interaction between ZnO and Se. Besides, Se-induced photocatalytic activity suppression of ZnO was demonstrated using methylene orange as an indicator. In vitro study revealed that ZnO–Se composite had improved biocompatibility over ZnO but comparable bacteriostasis ability under full-spectrum light irradiation. These results suggest that ZnO–Se composite is a promising UV blocker with advantages of facile synthesis, UV-induced ROS generation diminishment and biocompatibility. 相似文献
996.
Shanshan Ye Dan Luo Lizhen Shi Jianpeng Mou Junpeng Du Dewu Wu Jiangchong Zhou Jianyan Ding Quansheng Wu 《International Journal of Applied Ceramic Technology》2022,19(6):3367-3375
Lithium-containing silicates have been considered as a considerable alternative for luminescent materials. In this study, a novel cyan-emitting phosphor, Na3LiHf2Si3O12: Eu2+, was successfully synthesized via cationic substitution with Na4Hf2Si3O12: Eu2+ as the initial model. The crystal structure, morphology, and luminescence performance of Na4-xLixHf2Si3O12: Eu2+ were investigated in detail. The substitution of Li+ for Na+ site causes a significant blue-shift of the emission band in the range of 550–500 nm and a smaller full width at half maximum. As a result, a cyan phosphor Na3LiHf2Si3O12: Eu2+ that can be effectively excited by near-ultraviolet and high-energy beams is obtained. The mechanism of emission regulation was proposed based on the transformation of crystal structure and luminescence performance. In addition, the thermal quenching and cathodoluminescence behaviors were also studied. The results show that cation substitution is an effective method to design new lithium-containing silicate phosphors. 相似文献
997.
998.
Yuemin Lin Yuanyuan Zhang Renfeng Nie Kai Zhou Yao Ma Mingjie Liu Dan Lu Zongbi Bao Qiwei Yang Yiwen Yang Qilong Ren Zhiguo Zhang 《Frontiers of Chemical Science and Engineering》2022,16(12):1782
Ultra-dispersed Ni nanoparticles (7.5 nm) on nitrogen-doped carbon nanoneedles (Ni@NCNs) were prepared by simple pyrolysis of Ni-based metal–organic-framework for selective hydrogenation of halogenated nitrobenzenes to corresponding anilines. Two different crystallization methods (stirring and static) were compared and the optimal pyrolysis temperature was explored. Ni@NCNs were systematically characterized by wide analytical techniques. In the hydrogenation of p-chloronitrobenzene, Ni@NCNs-600 (pyrolyzed at 600 °C) exhibited extraordinarily high performance with 77.9 h–1 catalytic productivity and > 99% p-chloroaniline selectivity at full p-chloronitrobenzene conversion under mild conditions (90 °C, 1.5 MPa H2), showing obvious superiority compared with reported Ni-based catalysts. Notably, the reaction smoothly proceeded at room temperature with full conversion and > 99% selectivity. Moreover, Ni@NCNs-600 afforded good tolerance to various nitroarenes substituted by sensitive groups (halogen, nitrile, keto, carboxylic, etc.), and could be easily recycled by magnetic separation and reused for 5 times without deactivation. The adsorption tests showed that the preferential adsorption of –NO2 on the catalyst can restrain the dehalogenation of p-chloronitrobenzene, thus achieving high p-chloroaniline selectivity. While the high activity can be attributed to high Ni dispersion, special morphology, and rich pore structure of the catalyst. 相似文献
999.
Xuxin Zhao Kunling Yang Zhou Liu Ho Cheung Shum Tiantian Kong 《Frontiers of Chemical Science and Engineering》2022,16(11):1681
Bubbles and foams are ubiquitous in daily life and industrial processes. Studying their dynamic behaviors is of key importance for foam manufacturing processes in food packaging, cosmetics and pharmaceuticals. Bare bubbles are inherently fragile and transient; enhancing their robustness and shelf lives is an ongoing challenge. Their rupture can be attributed to liquid evaporation, thin film drainage and the nuclei of environmental dust. Inspired by particle-stabilized interfaces in Pickering emulsions, armored bubbles and liquid marble, bubbles are protected by an enclosed particle-entrapping liquid thin film, and the resultant soft object is termed gas marble. The gas marble exhibits mechanical strength orders of magnitude higher than that of soap bubbles when subjected to overpressure and underpressure, owing to the compact particle monolayer straddling the surface liquid film. By using a water-absorbent glycerol solution, the resulting gas marble can persist for 465 d in normal atmospheric settings. This particle-stabilizing approach not only has practical implications for foam manufacturing processes but also can inspire the new design and fabrication of functional biomaterials and biomedicines. 相似文献
1000.
Yang Zhang Guowu Zhan Yibo Song Yiping Liu Jiale Huang Shu-Feng Zhou Kok Bing Tan Qingbiao Li 《Frontiers of Chemical Science and Engineering》2022,16(12):1793
Recycling industrial solid waste not only saves resources but also eliminates environmental concerns of toxic threats. Herein, we proposed a new strategy for the utilization of petrochemical-derived carbon black waste, a waste vanadium-bearing resource (V > 30000 ppm (10 −6)). Chemical leaching was employed to extract metallic vanadium from the waste and the leachate containing V was used as an alternative raw material for the fabrication of vanadate nanomaterials. Through the screening of various metal cations, it was found that the contaminated Na+ during the leaching process showed strong competitive coordination with the vanadium ions. However, by adding foreign Ce3+ and Y3+ cations, two rare-earth vanadates, viz., flower-like CeVO4 and spherical YVO4 nanomaterials, were successfully synthesized. Characterization techniques such as scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier-transform infrared, and N2 physisorption were applied to analyze the physicochemical properties of the waste-derived nanomaterials. Importantly, we found that rare-earth vanadate catalysts exhibited good activities toward the semi-hydrogenation of α,β-unsaturated aldehydes. The conversion of cinnamaldehyde and cinnamic alcohol selectivity were even higher than those of the common CeVO4 prepared using pure chemicals (67.2% vs. 27.7% and 88.4% vs. 53.5%). Our work provides a valuable new reference for preparing vanadate catalysts by the use of abundant vanadium-bearing waste resources. 相似文献