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Yu J.,Harbin Institute of Technology | Meng L.,Harbin Institute of Technology | Fan D.,Harbin Institute of Technology | Zhang C.,Harbin Institute of Technology | And 2 more authors.
Composites Part B: Engineering | Year: 2014

Carbon fiber reinforced composite materials can be enhanced by introducing oxygen-containing groups on the surface of the reinforcing fibers to improve the interface bonding strength between carbon fibers and polymer matrix. While the addition of oxygen-containing groups has been shown to effectively increase the interfacial interaction between fibers and matrix, the treatments tend to consume the carbon fiber tensile strength. In this work, the surface of carbon fibers is oxidized by a chemical oxidation method which employs a strong oxidant of K2S2O8 and a catalyst of AgNO3 to effectively creating carboxyl and hydroxy functionalized surface and the reaction is shown that it can preserve the tensile strength and morphology of the carbon fibers. The surface oxidation is investigated by X-ray photoelectron spectroscopy, which shows that the relative surface coverage by oxygen atoms is increased from an initial 4.49% up to a maximum of 14.11% while the results of single fiber tensile strength tests demonstrate that the reaction did not lead to any obvious decrease in the fiber tensile strength. After oxidation, the interfacial shear strength (IFSS) improved from 59.52 to 96.73 MPa, with a increase of 62.5%. © 2014 Elsevier Ltd. All rights reserved. Source

Chu H.,Shandong University | Xin B.,Shandong University | Liu P.,Rizhao Entry Exit Inspection and Quarantine Bureau | Wang Y.,Shanghai JiaoTong University | And 6 more authors.
Biotechnology for Biofuels | Year: 2015

Background: Butane-2,3-diol (2,3-BD) is a fuel and platform biochemical with various industrial applications. 2,3-BD exists in three stereoisomeric forms: (2R,3R)-2,3-BD, meso-2,3-BD and (2S,3S)-2,3-BD. Microbial fermentative processes have been reported for (2R,3R)-2,3-BD and meso-2,3-BD production. Results: The production of (2S,3S)-2,3-BD from glucose was acquired by whole cells of recombinant Escherichia coli coexpressing the α-acetolactate synthase and meso-butane-2,3-diol dehydrogenase of Enterobacter cloacae subsp. dissolvens strain SDM. An optimal biocatalyst for (2S,3S)-2,3-BD production, E. coli BL21 (pETDuet-PT7-budB-PT7-budC), was constructed and the bioconversion conditions were optimized. With the addition of 10 mM FeCl3 in the bioconversion system, (2S,3S)-2,3-BD at a concentration of 2.2 g/L was obtained with a stereoisomeric purity of 95.0 % using the metabolically engineered strain from glucose. Conclusions: The engineered E. coli strain is the first one that can be used in the direct production of (2S,3S)-2,3-BD from glucose. The results demonstrated that the method developed here would be a promising process for efficient (2S,3S)-2,3-BD production. © 2015 Chu et al. Source

Su Z.,Rizhao Entry Exit Inspection and Quarantine Bureau | Zhang Y.-S.,Rizhao Entry Exit Inspection and Quarantine Bureau | Cheng L.,Rizhao Environmental Protection Bureau
Yejin Fenxi/Metallurgical Analysis | Year: 2012

In view of the geochemical characteristics of laterite nickel ore and the feature of containing mainly a high iron and low magnesium limonite in imported laterite nickel ore in China, a high precision and feasibility sampling and sample preparation method of bulk laterite nickel ore was established through a large amount of on-site experimental statistic data and reference to related sampling and preparation sample method of ISO, China, Japan. The proposed method was emplayed for sampling and sample preparation of a boat of laterite nickel imported from Indonesia. Through the determination of nickel, iron and water, it was found the sampling and preparation method precision(βs) and total precision (βspm) were all small and fit for the quality fluctuation law of goods, indicating a fine representativeness and reliability. The method is applicable to the sampling and sample preparation of imported nickel ore of China. Source

Jin W.,Rizhao Entry Exit Inspection and Quarantine Bureau | Hu S.-F.,Rizhao Entry Exit Inspection and Quarantine Bureau | Tian F.-L.,Rizhao Entry Exit Inspection and Quarantine Bureau
Xiandai Huagong/Modern Chemical Industry | Year: 2013

The cement sample is extracted with the ultrasonic method. The extracted solution is filtered using a 0.22 μm filter membrane. A Supp 4 type anion separation column is used to purify the obtained solution with the 1.8 mmol/L Na2CO3 and 1.7 mmol/L NaHCO3as eluents. The results show that the detection limit of Cl- is 30 μg/L. The linear correlation is good for the work curve and the linearly dependent coefficient is greater than 0.9999. The Cl- content determined by ion chromatography is basically consistent with the standard value. The relative standard deviation is not more than 1%. The method has wide linear range, simple operation, rapid analysis and less interference factors. The results are accurate and reliable with good repeatability and reproducibility, so it is a good method for determination of chloride ion content in the cement and cement clinker. Source

Yuan X.-Y.,Rizhao Entry Exit Inspection and Quarantine Bureau | Zhao G.-F.,Rizhao Entry Exit Inspection and Quarantine Bureau | Ye X.-Y.,Rizhao Entry Exit Inspection and Quarantine Bureau | Ma C.-J.,Rizhao Entry Exit Inspection and Quarantine Bureau
Chung-kuo Tsao Chih/China Pulp and Paper | Year: 2010

The basic conditions required by system design, the process flow and the equipment of the wood chips machine sampling system in Rizhao port, as well as the operation of the system are introduced. Such machine sampling system earlier application in national wide is suggested. Source

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