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排序方式: 共有316条查询结果,搜索用时 31 毫秒
1.
As a new type of quantum dots (QDs), hexagonal boron nitride quantum dots (BNQDs) exhibit promising potential in the applications of disease diagnosis, fluorescence imaging, biosensing, metal ion detection, and so on, because of their remarkable chemical stability, excellent biocompatibility, low cytotoxicity, and outstanding photoluminescence properties. However, the large-scale fabrication of homogeneous BNQDs still remains challenging. In this article, the properties and common fabrication methods of BNQDs are summarized based on the recent research progress. Then, the corresponding yields, morphologies, and fabrication mechanisms of these as-obtained BNQDs are discussed in detail. Moreover, the applications of these as-obtained BNQDs in different fields are also discussed. This article is expected to inspire new methods and improvements to achieve large-scale fabrication of homogeneous BNQDs, which will enable their practical applications in future. 相似文献
2.
Yaron Paz Ellina Kesselman Lulu Fahoum Irina Portnaya Ory Ramon 《Journal of Polymer Science.Polymer Physics》2004,42(1):33-46
The effect of two strong salting-out salts (Na2SO4 and K2SO4) on the temperature-induced phase-separation process in aqueous solutions of poly(N-isopropylacrylamide) (PNIPA) was examined by attenuated total reflectance/Fourier transform infrared spectroscopy, differential scanning calorimetry, and viscosity measurements. On the basis of these measurements, a detailed scenario of the phase-separation process was deduced. The phase-separation scenario of solutions containing PNIPA and water was altered in the presence of sulfate ions. Here, the sulfate ions induced partial intrachain collapse, manifested by a relatively compact structure well below the lower critical solution temperature. This led to a more gradual, smooth phase transition, with temperature-resolved intrachain collapse and interchain aggregation and a lesser extent of hysteresis. Although at the macrolevel one may not be able to differentiate among various scenarios altering the solvent into a poor solvent, the aforementioned microlevel measurements provided a way to expose the difference between raising the temperature and adding cosolutes. Follow-up studies on the effect of salting-in salts will be presented. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 33–46, 2004 相似文献
3.
Zhanglin Liu Dong Tian Fei Shen Lulu Long Yanzong Zhang Gang Yang Yongmei Zeng Jing Zhang Jinsong He Ying Zhu Shihuai Deng 《中国化学快报》1990,30(12):2221-2224
Four distinct biochars were employed to remove three typical pollutants, meanwhile, path analysis, a multi-statistical regression method, was performed to elucidate the dominant factors of biochar adsorption. This work can provide a new insight to prepare a targeted biochar as adsorbents. 相似文献
4.
Yuliang Zhang Leishan Shao Jingjing Li Qi Xu Lulu Liu Heng Zhang 《Liquid crystals》2013,40(10):1428-1435
In this study, we demonstrated that doping polymer matrix with a small amount of reduced graphene oxide (rGO) component (0.05–0.2%) had significant influence on the polymerisation kinetics and electro-optical performances of polymer-dispersed liquid crystal films (PDLCs) fabricated with macro reversible addition-fragmentation chain transfer agents. The effects of rGO content were studied in terms of morphology, compound viscosity, polymer conductivity, polymerisation kinetics and driving voltage of PDLCs. The results exhibited that higher rGO content increased the compound viscosity and the entire process proceeded slowly. Furthermore, the addition of rGO increased the polymer conductivity and local electric field, and reduced the saturation voltage as well as the threshold voltage from 27.3 to 19.5 V and 13.2 to 6.41 V, respectively. 相似文献
5.
Zhu Xiaoyang Wang Jing Chai Lulu Tang Guangshi Wan Kangni Pan Junqing 《Journal of Solid State Electrochemistry》2022,26(5):1163-1173
Journal of Solid State Electrochemistry - In this work, nanorods like bimetallic Zn/Mn metal–organic-frameworks (MOFs) are proposed as the precursor for preparing MnxOy/porous carbon... 相似文献
6.
Dr. Weixin Zou Lixia Xu Yu Pu Haojie Cai Xiaoqian Wei Yidan Luo Dr. Lulu Li Prof. Dr. Bin Gao Prof. Dr. Haiqin Wan Prof. Dr. Lin Dong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(19):5058-5064
Bimetallic AgPd nanoparticles have been synthesized before, but the interfacial electronic effects of AgPd on the photocatalytic performance have been investigated less. In this work, the results of hydrogen evolution suggest that the bimetallic AgPd/g-C3N4 sample has superior activity to Ag/g-C3N4 and Pd/g-C3N4 photocatalysts. The UV/Vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, CO adsorption diffuse reflectance FTIR spectroscopy, and FTIR results demonstrate that in the AgPd/g-C3N4, the surface electronic structures of Pd and Ag are changed, which is beneficial for faster photogenerated electron transfer and greater H2O molecule adsorption. In situ ESR spectra suggest that, under visible light irradiation, there is more H2O dissociation to radical species on the AgPd/g-C3N4 photocatalyst. Furthermore, DFT calculations confirm the interfacial electronic effects of AgPd/g-C3N4, that is, Pdδ−⋅⋅⋅Agδ+, and the activation energy of H2O molecule dissociation on AgPd/g-C3N4 is the lowest, which is the main contributor to the enhanced photocatalytic H2 evolution. 相似文献
7.
8.
Lulu Wang Jinmiao Wang Chuanbin Fan Caifeng Bi Xia Zhang Dongmei Zhang Mei Wang Yuhua Fan 《应用有机金属化学》2020,34(9):e5767
Two novel Co (II)- coordination polymers (CPs) based on 2,5-bis(4-carboxylpheny)-1,3,4-oxadiazole (bcpo), namely [Co/(bcpo)0.5(tib)(H2O)2]n (1) and [Co (bcpo)0.5(bidpe)(H2O)2]n (2) (tib = 1,3,5-tirs(1-imidazolyl)benzene, bidpe = 4,4′-bis (imidazolyl)diphenyl ether) have been synthesized under solvothermal conditions and characterized by powder X-ray diffraction (PXRD), single crystal X-ray diffraction, photochemistry as well as electrochemistry. The investigation of the photo-degradation methyl blue and methyl violet (MB, MV) properties of CPs 1–2 demonstrates that CP 1 shows great performance for the degradation of MB, and CP 2 could efficiently degrade MB/MV. Meanwhile, the possible photo-degradation mechanism has been proposed and explored. Simultaneously, electrochemistry studies show that both CPs 1 and 2 can catalyze water oxidation under an alkaline condition at the potential around 1.20 V vs. NHE with relatively low overpotential of 330–510 mV vs. NHE. 相似文献
9.
A high-performance liquid chromatography coupled with photodiode array detection and electrospray ionization tandem mass spectrometry (HPLC-PAD–ESI-MS) method has been developed for the simultaneous identification and quantification of active compounds (rutin and quercetin) contained in Traditional Chinese Medicine (TCM) Euonymus alatus (Thunb.) Siebold (EAS). The herb samples from ten main origins and five medicinal portions (leaf, fruit, stem, pterygium and root) were investigated. The separation was performed on a Shim C18 column at 30 °C with an isocratic elution. Methanol (A) and water (0.5% methanoic acid, v/v) (B) were used as mobile phases. The recoveries of the two compounds were 100.184% and 100.417%, respectively, and all of them showed good linearity (r2 ? 0.9993) in relatively wide concentration ranges. The developed method was applied to identify and quantify the two major active compounds in the collected herb samples, and the results indicated that contents of the two compounds in EAS varied significantly from habitat to habitat. It was demonstrated that the proposed method was helpful for the quality evaluation of EAS. 相似文献
10.
Lulu Huang Xiao Xiao Yinping Xie Hubert Kageruka Youe Zhou Fengjiao Deng Hongying Zhong 《Analytica chimica acta》2013
The inhomogeneous re-crystallization process of matrix materials is the major concerns associated with matrix assisted laser desorption/ionization (MALDI) analysis. We describe here the approach termed compressed matrix thin film (CMTF) in order to make a uniform matrix deposition. In this approach, solid matrix particles are compressed under 10 MPa of pressure by a compressor that is regularly used in infrared spectroscopic analysis. Then aqueous samples can be deposited on the surface of the matrix film. Major advantages of the CMTF approach are summarized as follows. (1) Reproducible sample preparation procedure. Size and thickness of matrix thin films can be controlled by using a fixed mold.force and known amount of matrix materials. (2) Significantly decreased shot-to-shot variations and enhanced reproducibility. (3) Tolerance for in situ salt washing. Because matrix materials are hydrophobic, salts can be washed away while proteins or peptides are retained on the surface of matrix thin films through hydrophobic interactions. (4) Improved sensitivity. The hydrophobic coating of MALDI sample plate by matrix thin films prevents the spreading of samples across the plate and confines analytes to a small area, leading to increased local concentration. (5) A new means for tissue analysis. Tissue sections can be directly transferred to the uniform surface of matrix materials for reproducible and quantitative comparison of different molecules in different localization. The proposed CMTF should be an enabling technique for mass spectrometric analysis with improved correlations between signal intensities and sample quantities. 相似文献