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Da’anshan, China

Guo H.,CAS Kunming Institute of Botany | Guo H.,Anshan Normal College | Guo H.,University of Chinese Academy of Sciences | Si J.,Beijing Forestry University | And 5 more authors.
Journal of Asian Natural Products Research | Year: 2013

Two new triterpenoids, 3β-(2-methoxy-oxalyloxy)-24-methylene-lanost-8- en-21-oic acid (1) and 3β-(2-methoxy-oxalyloxy)-15-hydroxy-24-methylene- lanost-8-en-21-oic acid (2), were isolated from cultures of the fungus Perenniporia maackiae, together with two previously known triterpenoids (3 and 4). Their structures were determined by spectroscopic methods, including 1D and 2D NMR, and MS analyses. All compounds were evaluated for their cytotoxic activities on five tumor cell lines. © 2013 Copyright Taylor and Francis Group, LLC. Source

Liu H.J.,University Of Science And Technology Liaoning | Wang H.Y.,Anshan Normal College
Advanced Materials Research | Year: 2013

For the dispersion problem of the widespread sensors in the R & D process of measuring instruments, this paper proposes a practical method for the automatic calibration of linearity error. Meanwhile, it takes the pressure sensor as an example to describe different calibration methods such as using the hardware, the combination of software and hardware, using the software. © (2013) Trans Tech Publications, Switzerland. Source

Lu Y.,Dalian Jiaotong University | Li M.,Anshan Normal College | Rahman A.,Tongji University | Shen J.,Tongji University | And 3 more authors.
Scripta Materialia | Year: 2014

The relationship between particle diffusion and free volume of colloidal glass was studied in real space by laser scanning confocal microscopy. By quantifying the particle diffusion distance and the free volume size, we found a strong spatial correlation between these two quantities. Large free-volume regions were observed to possess low elastic modulus and thus results in a low energy cost of diffusion-induced strain, indicating that a large free-volume region presents a low energy barrier to structural rearrangement, thereby benefiting particle diffusion. © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. Source

Wang Y.,Tongji University | Wang Y.,Northeast Petroleum University | Zheng Y.,CAS Shenyang Institute of Metal Research | Wang J.,CAS Shenyang Institute of Metal Research | And 2 more authors.
Jinshu Xuebao/Acta Metallurgica Sinica | Year: 2015

Amorphous alloy is a new type of material that exhibits exceptional properties or combinations of properties that are often not achievable in conventional crystalline materials. Fe-based amorphous alloys has attracted significant attention over the last few decades because of their low cost and enhanced mechanical performance. However, they are more suitable for the industrial application of coatings due to the fatal disadvantages of poor toughness. High velocity oxygen-fuel (HVOF) spraying is a good way to make amorphous alloy coatings (AMCs), for the individual droplets are cooled at a rate of around 107 K/s which is much higher than the critical cooling rate of the amorphous alloys during the thermal spraying. Fe-based AMCs obtained by using the HVOF spray method are important materials for industrial applications because of high glass-forming ability and exceptional performances, such as excellent corrosion resistance, high hardness, and superior wear resistance. In this work, FeCrMoMnWBCSi AMCs were prepared by HVOF thermal spray. The microstructure and amorphous characteristics of AMCs were characterized by SEM and XRD. Electrochemical corrosion behavior of AMCs was investigated in different concentration of NaCl and H2SO4 solutions compared with that of 304 stainless steel and ND steel. The surface film of materials after immersed in two solutions was analysed by XPS. The results indicated that HVOF thermal spraying Fe-based AMCs presented dense layered structure, high amorphous phase content and low porosity. The composite structure of AMCs was formed with some nanocrystallite phases embedded in the amorphous matrix. AMCs exhibited better resistance to pitting corrosion and relatively low uniform corrosion resistance due to the porosity, while the pitting potential of 304 stainless steel was sensitive to NaCl concentration. XPS results revealed that the presence of Cr, Mo and W oxides in the passive film of AMCs may result in the better corrosion resistance. The enrichment of Mo4+ oxides on the surface favored the formation of a more stable and protective layer which could be assumed to be responsible for the observed high stability of passive film. The diminishing or avording pores may be beneficial to further improve the pitting corrosion resistance of AMCs in NaCl solution. In all cases, AMCs showed better resistance to H2SO4 solutions corrosion due to the high stability of passive film. 304 stainless steel and ND steel presented stable passivation behavior only in high concentration of H2SO4 solution. In the lower concentration solution of H2SO4, the amorphous structure of the thinner coatings could facilitate the formation of thicker passivation film and lead to the higher corrosion resistance. The corrosion resistance of AMCs in H2SO4 solution could be enhanced significantly by formation of high amorphous phase. © Copyright. Source

Guo H.,CAS Kunming Institute of Botany | Guo H.,Anshan Normal College | Guo H.,University of Chinese Academy of Sciences | Feng T.,CAS Kunming Institute of Botany | And 2 more authors.
Journal of Asian Natural Products Research | Year: 2012

Four new compounds, craterellin D (1), 5-hydroxymethyl-2-hydroxy-4-methoxy- phenylethanone (2), 5-carboxyl-2-[2-(1,2-dihydroxyisopropyl)]-benzofuran (3), and 6-hydroxy-3-methoxy-4-methyl-2-cyclohexen-1-one (4), were isolated from cultures of the basidiomycete Craterellus odoratus, together with three known compounds craterellins A-C (5-7). Structures of 1-4 were elucidated on the basis of extensive spectroscopic analysis. Selected compounds were evaluated for their inhibitory activities against one isozyme of 11-hydroxysteroid dehydrogenase (11-HSD1) and cytotoxic activities on five tumor cell lines. Compound 2 was found to exhibit inhibitory activity against human 11-HSD1 with an IC50 value of 16.4g/ml. © 2012 Copyright Taylor and Francis Group, LLC. Source

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