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1.
《Advanced Powder Technology》2020,31(12):4585-4597
Focussing on visible light active ferrites for high performance removal of noxious pollutants, we report the synthesis of Mg0.5NixZn0.5-xFe2O4 (x = 0.1, 0.2, 0.3, 0.4, & 0.5) ferrite nanoparticle for degradation of reactive blue-19 (RB-19). Lattice parameters calculated using intense X-ray diffraction (XRD) peaks and Nelson-Riley plots (N-R plot) are in well agreement with each other. The sample Mg0.5Ni0.4Zn0.1Fe2O4 (M5N4) exhibits best performance with 99.5% RB-19 degradation in 90 min under visible light. Photoluminescence (PL) results confirm that recombination of charge carriers is highly reduced in the photocatalyst. Scavenging experiments suggest that O2 radicals were the dominant species responsible for photocatalytic performance. The photocatalytic mechanism was explained in terms of dopant driven shifting of conduction bands and valence bands (calculated by Mott-Schottky plots). The thermodynamic probability of radical generation along with role of redox cycles of metal ions has been discussed in the mechanism. The dye degradation was ascertained by detection of intermediates via mass spectrometry analysis and a possible degradation route was also predicted. The findings in this work provide intriguing opportunities to modify the electronic band structure of spinel ferrites for visible and solar light photocatalytic activity for environmental detoxification.  相似文献   
2.
We report on conductivity and optical property of three different types of poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) films [pristine PH1000 film (PH1000-p), with 5 wt.% ethylene glycol additive (PH1000-EG) and with sulfuric acid post-treatment (PH1000-SA)] before and after polyethylenimine (PEI) treatment. The PEI is found to decrease the conductivity of all the PEDOT:PSS films. The processing solvent of 2-methoxyethanol is found to significantly enhance the conductivity of PH1000-p from 1.1 up to 744 S/cm while the processing solvent of isopropanol or water does not change the conductivity of PH1000-p much. As for the optical properties, the PEI treatment slightly changes the transmittance and reflectance of PH1000-p and PH1000-EG films, while the PEI leads to an substantial increase of the absorptance in the spectral region of 400–1100 nm of the PH1000-SA films. Though the optical property and conductivity of the three different types of PEDOT:PSS films vary with the PEI treatment, the treated PEDOT:PSS films exhibit similar low work function. We demonstrate solar cells with a simple device structure of glass/low-WF PEDOT:PSS/P3HT:ICBA/high-WF PEDOT:PSS cells that exhibit good performance with open-circuit voltage of 0.82 V and fill factor up to 0.62 under 100 mW/cm2 white light illumination.  相似文献   
3.
The non-equiatomic FeCoNiAlSi alloy is prepared by the Bridgman solidification (BS) technique at different withdrawal velocities (V = 30, 100, and 200 μm/s). Various characterization techniques have been used to study the microstructure and crystal orientation. The morphological evolutions accompanying the crystal growth of the alloy prepared at different withdrawal velocities are nearly the same, from equiaxed grains to columnar crystals. The transition of coercivity is closely related to the local microstructure, while the saturation magnetization changes little at different sites. The coercivity can be significantly reduced from the equiaxed grain area to the columnar crystal area when the applied magnetic field direction is parallel to the crystal growth direction, no matter what is the withdrawal velocity. In addition, the alloy possesses magnetic anisotropy when the applied magnetic field is in different directions.  相似文献   
4.
Using a comprehensive set of drop weight impact test data (h50) newly compiled from literature for 308 materials, a recent approach to predict impact sensitivities of nitro compounds is generalized to most explosive substances of interest. Compared to previous ones, this procedure is more thoroughly validated and exhibits a good predictive value. Furthermore, it yields new insight into the physical mechanisms involved, explaining for instance the unexpected desensitization of some oxygen-deficient triazoles upon nitration.  相似文献   
5.
储层应力敏感性影响因素研究   总被引:16,自引:5,他引:11  
全面分析储层应力敏感性产生的机理认为,外部因素的改变会引起储层产生应力敏感性.而储层岩石物性等内部因素对应力敏感性的强弱起决定性作用。室内岩心应力敏感性评价时.仪器与设备的精度、加载与卸载方式、实验用流体类型以及各种人为因素等都会对评价结果产生影响,其中岩心密封套在高压、高温条件下的密闭性会对实验结果产生较大影响。所以储层应力敏感性不应该从孔隙度和渗透率的高低进行简单评价,中、高渗储层和低渗储层在生产过程也都可能表现出较强的应力敏感性现象。  相似文献   
6.
Six genotypes of sweet potato commercially available in Taiwan, including TNG57, TNG66, TNG68, TYY1, RP and WP, were used as samples in this study of the effects of steaming and kneading with pre-steaming treatments on the antioxidant components and antioxidant properties of methanolic extracts. Steam treatment increased the total phenols contents of all genotypes (2–13 times), flavonoids content of RP (1.3 times) and anthocyanins contents of RP and WP (5–6 times). Steam treatment also increased the reducing power and scavenging DPPH radical effect of sweet potato flours. For the methanolic extracts of steamed and kneaded flours, reducing powers were 0.02–1.70 at 5.0 mg ml−1 and the scavenging effects on DPPH radicals were 19–92% at 2.5 mg ml−1. Both showed the order of RP > WP > TYY1 and TNG66 > TNG57 and TNG68. However, the chelating effect of the six genotypes at 1.0 mg ml−1 ranged from 50% to 73%. Contents of total phenols, flavonoids, and anthocyanins of sweet potato flours were significantly positively correlated with the reducing power and scavenging DPPH radical effects. After steaming and kneading treatments, RP showed the highest increase in the contents of total phenols, flavonoids and anthocyanins among the six genotypes studied.  相似文献   
7.
Effect of stoichiometry on microstructures, electrochemical properties and PCT characteristics of the alloys MI(Ni0.71Co0.15-Al0.06Mn0.08)x (MI=Lanthanum-rich Michmetal, x=4.6~5.2) have been investigated. The lattice constants a, c, and cellvolumes of non-stoichiometric alloys are bigger than those of the stoichiometric alloy. With the increasing stoichiometry x,the value of a decreases, and the value of c and cell volume increases except for those of the stoichiometric alloy; the plateaupressure of PCT curve, discharge capacity and cycling stability all increase. The alloy with x=5.2 shows the highest dischargecapacity and the best cycling stability among the studied alloys.  相似文献   
8.
套保稠油油田火烧油层可行性分析   总被引:2,自引:1,他引:1  
从火烧油层的筛选标准、实际地质条件及室内物理模拟实验入手,对该油田火烧可行性进行了分析。分析结果认为,套保油田进行火烧总体上是可行的,在实际火烧时应避开底水的影响,火烧区域应选在构造高部位或仅烧其主力层。  相似文献   
9.
水煤浆燃烧技术及其发展   总被引:9,自引:1,他引:8  
分析了水煤浆雾化燃烧的技术状况、应用方向和存在问题,介绍了水煤浆流化—悬浮高效洁净燃烧新技术及其优点,结合实践应用情况,分析了发展水煤浆流化—悬浮燃烧技术的意义和应用前景。  相似文献   
10.
本文在液相合成(SrPb)TiO3粉的基础上,研究了升温速率、保温时间、烧结温度及降温方式对(SrPb)TiO3基陶瓷的V型PTC热敏特性的影响。实验表明:升温速率对其热敏特性影响不大,保温时间和烧结温度的作用是一致的,具有一最佳范围。而降浊方式对材料的热敏特性影响较大。综合各因素的影响,本配方中,样品的烧结制度定为:以200℃/h的速率升温,在1250℃保温1h,炉冷至950℃,保温0.5h,再  相似文献   
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