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1.
Hang Qin Wenming Guo Pengzhao Gao Hanning Xiao 《Journal of the European Ceramic Society》2021,41(4):2724-2733
Two types of spherical zirconyl oxalate aqueous sols were successfully customized by a reverse micelles-mediated aqueous sol-gel process, and the sols were sequentially spin-coated on porous supports to prepare ZrO2 loose/tight bilayer ultrafiltration membranes. After three times of spin-coating process, a defect-free ZrO2 loose ultrafiltration membrane with pure water permeability of 110.5 ± 2.25 L m?2 h-1 bar-1, molecular weight cut-off (MWCO) of 16.5 kDa and excellent rejection of up to 97.5 % for bovine serum albumin was fabricated. Then, the loose ultrafiltration membrane was used as a substrate to prepare ZrO2 tight ultrafiltration membrane. Performances of tight ultrafiltration membrane regarding to permeability, retention of polyethylene glycol and treatment of dyes wastewater were evaluated. The tight ultrafiltration membrane with a thickness of 200 nm exhibited a pure water permeability of 22.5 ± 0.3 L m-2 h-1 bar-1 and MWCO of 1150 Da. Additionally, the rejections of methyl red and methyl orange by the tight ultrafiltration membrane were both <65 %, while of alizarin red, direct red, bromocresol green and methyl blue achieved maximum values of 98.5 %, 99.2 %, 99.5 % and 99.6 %, respectively. The fouled membranes could restore the virgin performance for reuse by cleaning and low-temperature calcination. 相似文献
2.
Yi Qin Tao Xiong Ting Zhao Jianfeng Zhu Jun Yang Yi Liu Xingang Kong Xiaohan Li 《Ceramics International》2021,47(9):12641-12650
The strengthening method of multi-element M-site solid solution is a common approach to improve mechanical properties of MAX phase ceramic. However, the research on capability of multi-element A-site solid solution to improve mechanical properties has rarely been reported. Thereupon, quasi-high-entropy MAX phase ceramic bulks of Ti2(Al1?xAx)C and Ti3(Al1?xAx)C2 (A = Ga, In, Sn, x = 0.2, 0.3, 0.4) were successfully synthesized by in situ vacuum hot pressing via multi-elements solid solution. The multi-elements solid solution in single-atom thick A layer was confirmed by X-ray diffraction and X-ray photoelectron spectroscopy as well as by energy dispersive X-ray spectroscopy mappings. Effects of doped multi-elements contents on the phase, microstructure, mechanical properties, and high temperature tribological behaviors were studied. Results demonstrated that the Vickers hardness, anisotropic flexural strength, fracture toughness, and tribological properties of Ti–Al–C based MAX ceramics could be remarkably improved by constitution of quasi-high-entropy MAX phase in A layers. Moreover, the strengthening and wear mechanisms were also discussed in detail. This method of multi-element solid solution at A-site provides new way to enhance mechanical properties of other MAX phase ceramics. 相似文献
3.
Yujing Zhang Pin Liu Kumara Raja Kandula Wenru Li Yanfeng Qin Haibo Zhang Guangzu Zhang 《Journal of the European Ceramic Society》2021,41(1):360-367
The applications of antiferroelectric (AFE) materials in miniaturized and integrated electronic devices are limited by their low energy density. To address the above issue, the antiferroelectricity of the reinforced material was designed to improve its AFE-ferroelectric (FE) phase transition under electric fields. In this present study, the composition of Zr4+ (0.72 Å) and Ti4+ (0.605 Å) at B-site of Pb0.97La0.02(ZrxSn0.05Ti0.95-x)O3 ceramics with orthogonal reflections are synthesized via the tape-casting method. These ceramics are modified to enhance their antiferroelectricity by reducing their tolerance factor. A recoverable energy storage density Wrec 12.1 J/cm3 was obtained for x = 0.93 under 376 kV/cm, which is superior value than reported until now in lead-based energy storage systems. Moreover, the discharge energy density can reach 10.23 J/cm3, and 90 % of which can be released within 5.66 μs. This work provides a new window and potential materials for further industrialization of pulse power capacitors. 相似文献
4.
5.
自然通风广泛存在于城市之中,了解城市自然通风建筑室内环境质量现状及存在的问题,是改善城市建筑室内环境质量的基础. 通过文献整理,首先研究城市街道峡谷中单侧自然通风的驱动因素,其次从建筑几何特征、通风能力、污染率、颗粒物浓度以及街谷设施等方面综述单侧自然通风的相关研究,最后提出建议. 研究表明,合理的展弦比、更好的城市布局以及精心的街谷设施设计能够最大限度地利用单侧自然通风,提升城市街道峡谷的室内环境品质. 相似文献
6.
针对动态非刚性在线重建存在的重建漂移问题,提出了一种基于单个RGB-D传感器的稠密变形场在线融合策略,实现了对非刚性几何形状的动态重建.通过局部平滑和输入约束处理,将空间的最优变形转换为非线性正则变分优化问题,并使用数据并行闪存优化策略,以摄像机捕获速率,实现对非刚性场景的在线跟踪重建.通过实验表明,本文方法实现了对非刚性场景的鲁棒跟踪,减少了在线重建过程中的漂移现象,适用于快速运动和缺乏几何特征的场景重建. 相似文献
7.
Shucheng Qin Zhenrong Jia Lei Meng Can Zhu Wenbin Lai Jinyuan Zhang Wenchao Huang Chenkai Sun Beibei Qiu Yongfang Li 《Advanced functional materials》2021,31(25):2102361
Organic solar cells (OSCs) have recently reached a remarkably high efficiency and become a promising technology for commercial application. However, OSCs with top efficiency are mostly processed by halogenated solvents and with additives that are not environmentally friendly, which hinders large-scale manufacture. In this study, high-performance tandem OSCs, based on polymer donors and two small-molecule acceptors with different bandgaps, are fabricated by solution processing with non-halogenated solvents without additive. Importantly, the two active layers developed from non-halogenated solvents show better phase segregation and charge transport properties, leading to superior performance than halogenated ones. As a result, a tandem OSC with high efficiency of up to 16.67% is obtained, showing unique advantages in future massive production. 相似文献
8.
Shuhai Liu Ming Han Xiaolong Feng Qiuhong Yu Long Gu Longfei Wang Yong Qin Zhong Lin Wang 《Advanced functional materials》2021,31(17):2010339
Utilizing inner-crystal piezoelectric polarization charges to control carrier transport across a metal-semiconductor or semiconductor–semiconductor interface, piezotronic effect has great potential applications in smart micro/nano-electromechanical system (MEMS/NEMS), human-machine interfacing, and nanorobotics. However, current research on piezotronics has mainly focused on systems with only one or rather limited interfaces. Here, the statistical piezotronic effect is reported in ZnO bulk composited of nanoplatelets, of which the strain/stress-induced piezo-potential at the crystals’ interfaces can effectively gate the electrical transport of ZnO bulk. It is a statistical phenomenon of piezotronic modification of large numbers of interfaces, and the crystal orientation of inner ZnO nanoplatelets strongly influence the transport property of ZnO bulk. With optimum preferred orientation of ZnO nanoplatelets, the bulk exhibits an increased conductivity with decreasing stress at a high pressure range of 200–400 MPa, which has not been observed previously in bulk. A maximum sensitivity of 1.149 µS m−1 MPa−1 and a corresponding gauge factor of 467–589 have been achieved. As a statistical phenomenon of many piezotronic interfaces modulation, the proposed statistical piezotronic effect extends the connotation of piezotronics and promotes its practical applications in intelligent sensing. 相似文献
9.
Wan-Li Tan Dr. Chun Zhang Yang Li Dr. Kai Guo Dr. Xiao-Wei Gao Dr. Jun Wei Dr. Dong Yi Prof. Lin Pu Prof. Dr. Qin Wang 《ChemMedChem》2021,16(23):3569-3575
Forty samples of optically active falcarindiol analogues are synthesized by using the easily available C2 symmetric (R)- and (S)-1,1’-binaphth-2-ol (BINOL) in combination with Ti(OiPr)4, Zn powder and EtI. Their anticancer activities on Hccc-9810, HepG2, MDA-MB-231, Hela, MG-63 and H460 cells are assayed to elucidate their structure-activity relationships. These results showed that the falcarindiol analogue (3R,8S)- 2 i with the terminal double bond has the most potent anti-proliferation effect on Hccc-9810 cells with IC50 value of 0.46 μM. The falcarindiol analogue (3R,8S)- 2 i can induce obvious Hccc-9810 cell apoptosis in a concentration-dependent manner by Hoechst staining and flow cytometry analysis. The proposed mechanism suggests that the falcarindiol analogue (3R,8S)- 2 i increases LDH release and MDA content, and reduces the levels of SOD activity, which lead to the accumulation of oxidative stress and induce apoptosis in Hccc-9810 cells. 相似文献
10.
海南小型露天采石场矿山数量多且呈遍地开花式分布,且不规范的开采对环境造成较大的破坏,与绿色矿山之路背道而行,相对大型矿山规范化的治理,小型矿山治理比较滞后,本文以日富采石场地质环境治理为例,通过摸清当地的地质环境条件,结合矿山现状,因地制宜地制定出日富采石场地质环境治理的具体措施,通过治理可获得林地2.6hm2,矿山安全隐患及地貌景观等矿山地质环境问题得到有效地防治,有效解决农业灌溉及周边虾塘养殖用水缺乏问题,实现较好的社会经济效益,为今后治理类似矿山提供参考。 相似文献