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排序方式: 共有3292条查询结果,搜索用时 15 毫秒
1.
Injun Lee Taeseong Jung Junggi Kim Suho Ro Chulsu Kim Yeji Lee Youngmi Kim Juhyun Lee Misook Kang 《Journal of Industrial and Engineering Chemistry》2008,14(6):869-873
This study focuses on the relationship between photo-catalytic performance and optical property over Si-incorporated TiO2. The Si-incorporated TiO2 particles exhibited a pure structure of anatase having a particle size of less than 20 nm and surface area of more than 190 m2/g. The absorbance did not shift to a higher wavelength in spite of the incorporation of the Si ions, but the intensity of the photoluminescence (PL) curve was the smallest in the case of the 2.0 mol% Si-TiO2, which was related to the recombination between the excited electrons and holes. Based on these results, the photodecomposition of methyl orange in the liquid reaction was enhanced over the 2.0 mol% Si-incorporated TiO2 compared with that over pure TiO2: Methyl orange at 10.0 ppm was completely decomposed after 100 min when 1.0 g of the 2.0 mol% Si-incorporated TiO2 was used. 相似文献
2.
Photocatalytic degradation of methyl orange using heteropolytungstic acid-encapsulated TiSBA-15 总被引:1,自引:0,他引:1
Heteropolyphosphotungstic acid (H3PW12O40) (HPA)-encapsulated titanium-supported SBA15 nanoporous materials (HPA-TiSBA-15) were synthesized as a new photocatalyst, and they were characterized by FT-IR and 31P NMR MAS spectroscopic methods. Their photocatalytic effects on degradation of methyl orange in water were investigated under natural conditions, and it was found that a 4-fold increase in the photodegradation rate is observed in the presence of HPA-TiSBA-15 as compared to the rate observed in the presence of titanium-supported SBA15 nanoporous materials (TiSBA-15) without HPA. 相似文献
3.
金属-橡胶硫化粘接过程中分子取向行为的间接证据 总被引:2,自引:1,他引:1
对金属-橡胶热硫化粘接复合体的剥离行为进行了研究,同一粘接试样的双向180°剥离试验显示出了巨大的差异。本文分析了弹性材料在硫化过程中的分子行为,并提出了相应的新假设,认为这是由于金属-橡胶在硫化粘接过程中分子取向交联行为所致。这种双向180°剥离破坏现象可被看作是金属-橡胶硫化粘接过程中分子取向行为的间接证据。 相似文献
4.
Nanocrystalline thin films of important surface roughness and complexity were prepared by screen-printing of commercial TiO2 powder. The screen-printed titania films were tested in the photocatalytic decomposition reaction of methyl orange under UV light (350 nm). The photocatalytic activity strongly depends on the titania paste components and especially on the presence of a surface modifier (acetyl acetone) combined with a rheology controlling agent (ethyl cellulose). This results in improvement of the paste viscosity and optimization of the films morphology. Experiments under direct full sunlight illumination prove the importance of the screen-printed films for practical applications. 相似文献
5.
Analyses of the practical adhesion strengths of the metal/polymer interfaces in electronic packaging
There is a plethora of techniques to measure the adhesion strength of metal/polymer interfaces. However, the practical adhesion
strength, which is the work done in separating the film from the substrate (or one film from another), is very sensitive to
the test methods and the mechanical effects, such as the residual stress, thickness and mechanical properties of the layers,
strain rate, and phase angle. Deriving intrinsic-adhesion properties of the interfaces, which are independent of such parameters,
from the practical adhesion-strength measurements is a formidable task. In the present work, data from the three commonly
used adhesion tests; pull-out, 90°-peel, and T-peel tests are compared with the intrinsic-adhesion properties of the interface,
such as the interface-fracture toughness or the interface-fracture energy, and their implications are discussed. Material
systems analyzed were Cu-based lead frame/epoxy-molding compound (EMC) and Cu/Cr/polyimide. 相似文献
6.
Thermodynamic parameters have been determined for the interaction of methyl orange and poly(vinylpyrrolidone) in aqueous solutions containing tris, tris and hydrochloric acid, or water only. Enthalpy changes were determined by use of a flow microcalorimeter. Free energy changes were calculated from the results of equilbrium dialysis studies. The results are interpreted in terms of the behaviour of poly(vinylpyrrolidone) in these systems. Analysis of data shows that the hydrophobic interactions in the systems are in the order: tris > wateronly > tris-HC1. 相似文献
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9.
GJ5×2双槽剥片机及其在高岭土剥片中的应用 总被引:2,自引:0,他引:2
GJ5×2大型双槽剥片机是国内超细物料加工中最新出现的超细磨/剥片设备,也是目前国内这一领域内最大规格的设备,已成功应用于煤系硬质高岭土剥片中,单机能力可达1.5~2.0t/h,产品细度可达小于2μm颗粒占85%~90%。 相似文献
10.
This study investigated the peculiar “orange peel” effect often observed in nanomaterials using high-resolution scanning electron microscopes. The study used different materials, including semiconductor thin films and ceramic nanoparticles. The investigation established that the “orange peel” is of an artifact caused by the metallic coating of the samples in sample preparation. This discovery is important in eliminating the misinterpretation of such effect on the true surface feature of materials, hence avoiding the confusion in the discussion of the properties of nanomaterials. 相似文献