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An Al 2024 (AA2024-T351) alloy having less Mg and a higher proportion of Cu to Mg (mass ratio ≈3.7) has been characterised to provide input data for microscale and macroscale corrosion models. The Al 2024 alloy microstructure has a significant presence of nanoscale dispersoid and microscale AlCuFeMnSi (2nd phase) intermetallic particles, but a smaller population of microscale S phase (Al2CuMg) and θ phase (Al2Cu) intermetallic particles. Microscale electrochemical data show that pitting potential (SCE) values for 2nd phase, S phase, or matrix overlap significantly. The localised corrosion susceptibility is affected by S and inhomogeneous 2nd phase particles. 相似文献
97.
预吸附水对低阶煤成浆性能的影响 总被引:1,自引:0,他引:1
针对低阶煤由于内水分高、含氧量高导致的成浆性差的问题,研究了预吸附水对低阶煤成浆性能的影响.结果表明,预吸附水处理后低阶煤的成浆性能得到了较大的提高,当制浆浓度达到63%时黏度仅为1 200 mPa·s,比相同黏度下原煤制浆浓度提高了约3%.元素分析结果表明,预吸附水后低阶煤含氧官能团含量没有发生变化;比表面积和孔隙结构测试结果表明,煤样预吸附水处理后比表面积减少,吸附水阻塞了一部分中孔,使总孔容积减少,减少了煤孔隙中分散剂的吸附,同时预吸附水使煤样的润湿性能增强,煤粒间的静电斥力增加,从而提高了低阶煤的成浆性能. 相似文献
98.
The breakage of liquid-liquid, solid-liquid and solid-gas dispersions occurs in many industrial processes during the transport of particulate materials. In this work, breakage of whey protein precipitates passing through a capillary pipe is examined and an experimentally derived breakage frequency is applied to construct a suitable population balance model to characterize the breakage process. It has been shown that the breakage frequency of precipitate particles is highly dependent on their shear history and on the turbulent energy dissipation rate in the pipe. The population balance equation (PBE) uses a volume density based discrete method which is adapted from mass density based discretization. In addition to comparing the model with experimental data, predicted results at different velocities are presented. It was found that the population balance breakage model provides satisfactory results in terms of predicting particle size distributions for such processes. 相似文献
99.
Comb‐type grafted hydrogels composed of polyacrylamide (PAAm) and chitosan (CT) were prepared and used for DNA adsorption. Instead of direct grafting of the acrylamide monomer onto the CT chain, semitelechelic PAAm with carboxylic acid end groups (PAAm–COOH) was synthesized by free‐radical polymerization with mercaptoacetic acid as the chain‐transfer agent, and it was grafted onto CT with amino groups. The synthesis of telechelic PAAm–COOH and the formation of comb‐type grafted hydrogels were confirmed by attenuated total reflectance/Fourier transform infrared spectroscopy and scanning electron microscopy measurements. The prepared comb‐type grafted hydrogels were used as sorbents in DNA adsorption experiments conducted at +4°C in a tris(hydroxymethyl)aminomethane/ethylenediaminetetraacetic acid solution of pH 7.4. DNA adsorption capacities as high as 2.0 × 103 μg of DNA/g of dry gel could be achieved by the comb‐type hydrogels with higher PAAm contents. This value was approximately 6 times higher than that of CT alone. In addition, the comb‐type hydrogels showed a high adsorption/desorption rate depending on the PAAm content in the hydrogel. As a result, these comb‐type hydrogels carrying higher amounts of DNA may be considered good candidates for achieving higher removal rates for anti‐DNA antibodies and for effective gene therapy systems. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
100.
Hao Yang Qing Guo Rong He Ding Li Xueqing Zhang Chenchen Bao Hengyao Hu Daxiang Cui 《Nanoscale research letters》2009,4(12):1469-1474
Quantum dot is a special kind of nanomaterial composed of periodic groups of II–VI, III–V or IV–VI materials. Their high quantum
yield, broad absorption with narrow photoluminescence spectra and high resistance to photobleaching, make them become a promising
labeling substance in biological analysis. Here, we report a quick and parallel analytical method based on quantum dots for
ToRCH-related antibodies including Toxoplasma gondii, Rubella virus, Cytomegalovirus and Herpes simplex virus type 1 (HSV1)
and 2 (HSV2). Firstly, we fabricated the microarrays with the five kinds of ToRCH-related antigens and used CdTe quantum dots
to label secondary antibody and then analyzed 100 specimens of randomly selected clinical sera from obstetric outpatients.
The currently prevalent enzyme-linked immunosorbent assay (ELISA) kits were considered as “golden standard” for comparison.
The results show that the quantum dots labeling-based ToRCH microarrays have comparable sensitivity and specificity with ELISA.
Besides, the microarrays hold distinct advantages over ELISA test format in detection time, cost, operation and signal stability.
Validated by the clinical assay, our quantum dots-based ToRCH microarrays have great potential in the detection of ToRCH-related
pathogens. 相似文献