Research on the Acid Fastness of Polyphenylene Sulfide Fiber

2011 ◽  
Vol 332-334 ◽  
pp. 281-285
Author(s):  
Xiu Hua Wang ◽  
Yan Fen Qin ◽  
Ji Xian Wan ◽  
Shao Bo Li ◽  
Yong Zhan ◽  
...  

Polyphenylene sulfide (PPS) fiber is a kind of high-performance fiber. This paper aimed at investigating the acid resistant performance of PPS fiber. The corrosive action of PPS fiber in nitric acid (HNO3), sulfuric acid (H2SO4), hydrochloric acid (HCl), the mixture of HNO3 and HCl, the mixture of HNO3 and H2SO4, the mixture of HNO3, H2SO4 and HCl were researched. In addition, the influence of various acid concentrations on the performances of the PPS fiber was also studied in the paper. The acid-treated sample was analyzed by the fiber tensile instrument, the Fourier infrared spectrometer, and the scanning electron microscope (SEM) to observe the change of mechanical performance, configuration and appearance.

Author(s):  
Marc H. Peeters ◽  
Max T. Otten

Over the past decades, the combination of energy-dispersive analysis of X-rays and scanning electron microscopy has proved to be a powerful tool for fast and reliable elemental characterization of a large variety of specimens. The technique has evolved rapidly from a purely qualitative characterization method to a reliable quantitative way of analysis. In the last 5 years, an increasing need for automation is observed, whereby energy-dispersive analysers control the beam and stage movement of the scanning electron microscope in order to collect digital X-ray images and perform unattended point analysis over multiple locations.The Philips High-speed Analysis of X-rays system (PHAX-Scan) makes use of the high performance dual-processor structure of the EDAX PV9900 analyser and the databus structure of the Philips series 500 scanning electron microscope to provide a highly automated, user-friendly and extremely fast microanalysis system. The software that runs on the hardware described above was specifically designed to provide the ultimate attainable speed on the system.


1980 ◽  
Vol 59 (2) ◽  
pp. 124-128 ◽  
Author(s):  
Y. Galindo ◽  
K. McLachlan ◽  
Z. Kasloff

A silver-plating technique was developed in an effort to produce good mechanical bonding characteristics between stainless steelpins and amalgam. Metallographic microscope and scanning electron microscope (SEM) studies were made to assess the presence, or otherwise, of such a bond between (a) the silver layer plating and the surface of the stainless steel pins, and (b) and silver plating and the amalgam. Unplated stainless steel and sterling silver pins were used as a control and as a comparison, respectively. A "rubbing" technique of condensation was devised to closely adapt amalgam to the pins. It is concluded that there is strong evidence for the existence of a good bond between the plated pins and amalgam. The mechanical performance of the bond is discussed elsewhere. 1.


2020 ◽  
Vol 70 (1) ◽  
Author(s):  
Xiujie Gong ◽  
Hongtao Zou ◽  
Chunrong Qian ◽  
Yang Yu ◽  
Yubo Hao ◽  
...  

Abstract Purpose The highly efficient degradation bacteria were selected from the humus from the very cold straw in China for many years to construct the in situ degradation bacteria, and the degradation efficiency of corn straw was determined by process optimization. Methods According to the main components of corn straw, through morphological, physiological, and biochemical screening, three highly efficient complementary degradation strains were selected to construct the compound flora, and the degradation efficiency was analyzed by Fourier transform infrared spectrometer, field emission scanning electron microscope, and X-ray diffractometer. Result The corn straw selected in this paper is mainly composed of cellulose (31.99%), hemicellulose (25.33%), and lignin (14.67%). Through the determination of enzyme activity, strain Streptomyces sp. G1T has high decomposition ability to cellulose and hemicellulose but weak utilization ability to lignin; strain Streptomyces sp. G2T has the strongest decomposition ability to cellulose and hemicellulose among the three strains. The decomposition ability of strain Streptomyces sp. G3T to lignin was the strongest among the three strains. Therefore, by compounding the three strains, the decomposition ability has been greatly improved. The optimal process conditions obtained by single factor and response surface method are as follows: pH is 7, temperature is 30 °C, inoculation amount is 5%, rotational speed is 210 rpm, and the weight loss rate of straw is 60.55% after decomposing for 7 days. A large amount of degradation of corn straw can be seen by Fourier transform infrared spectrometer, field emission scanning electron microscope, and X-ray diffractometer. Conclusion Streptomyces sp. G1T, Streptomyces sp. G2T, and Streptomyces sp. G3T screened from straw humus in very cold areas were used to construct in situ degradation bacteria, which had good straw degradation activity and had the potential to be used for straw treatment in cold areas after harvest. This characteristic makes the complex bacteria become a strong competitive candidate for industrial production, and it is also an effective biotechnology in line with the current recycling of resources.


2011 ◽  
Vol 311-313 ◽  
pp. 473-476
Author(s):  
Jian Hua Du ◽  
Jian Guo Han ◽  
Cheng Fa Xu

The Cu-based friction materials with nano-AlN (n-AlN) and nano-graphite (n-C) were prepared by powder metallurgy technology, respectively. The microstructures and friction performance were studied through scanning electron microscope (SEM) and friction tester rig, respectively. The results indicate that the n-AlN and n-C particles can enhance the properties of Cu-based friction materials remarkably. Compared with the friction materials without any nanometer materials, the wear resistance of the friction materials with n-AlN and n-C has been improved by 25 % and 11 %, respectively. The heat resistance of the materials with n-AlN and n-C has been improved 18 % and 25 %, respectively. The n-AlN and n-C particles can reduce the abrasive wear and enhance the wear resistance of the Cu-based friction materials.


Author(s):  
B. F. Luan ◽  
L. Q. Yang ◽  
T. G. Wei ◽  
K. L. Murty ◽  
C. S. Long ◽  
...  

To investigate the effects of Mo and Bi on mechanical properties of a Zr-Fe-Cr alloy at room temperature, seven Zr-Fe-Cr-Mo-Bi alloys with different compositions were designed. They were subjected to a series of rolling processes and heat treatments, and then sampled to measure mechanical properties by hardness and tensile test and to characterize microstructures by scanning electron microscope (SEM) and electron channel contrast (ECC) technique. Results indicated that among them two types of Zr-Fe-Cr-Mo-Bi alloys achieve the designed goals on mechanical properties and have the following advantages: (i) the hardness of the alloys, up to 334HV after annealing, is 40% higher than traditional Zr-4. (ii) The yield strength (YS) and ultimate tensile strength (UTS) of the alloys are 526 MP a and 889 MP a after hot rolling and annealing, markedly higher than the traditional Zr alloy. (iii) Good plasticity of the new Zr-Fe-Cr-Mo-Bi alloy is obtained with about 40% elongation, which is greatly higher than the Zr-Fe-Cr-Mo alloy thanks to the addition of Bi offsetting the disadvantage of addition Mo. Furthermore, according to observations of the microstructure observation, the reasons of the effect of the Mo and Bi elements on the mechanical performance of Zr-Fe-Cr alloy were studied and discussed.


2017 ◽  
Vol 88 (1) ◽  
pp. 75-81 ◽  
Author(s):  
Josko Viskic ◽  
Drazen Jokic ◽  
Suzana Jakovljevic ◽  
Lana Bergman ◽  
Sladana Milardovic Ortolan ◽  
...  

ABSTRACT Objective: To evaluate the surface of glazed lithium disilicate dental ceramics after irradiation under different irradiation settings of Nd:YAG and Er:YAG lasers using a scanning electron microscope (SEM). Materials and Methods: Three glazed-press lithium disilicate ceramic discs were treated with HF, Er:YAG, and Nd:YAG, respectively. The laser-setting variables tested were laser mode, repetition rate (Hz), power (W), time of exposure (seconds), and laser energy (mJ). Sixteen different variable settings were tested for each laser type, and all the samples were analyzed by SEM at 500× and 1000× magnification. Results: Surface analysis of the HF-treated sample showed a typical surface texture with a homogenously rough pattern and exposed ceramic crystals. Er:YAG showed no effect on the surface under any irradiation setting. The surface of Nd:YAG-irradiated samples showed cracking, melting, and resolidifying of the ceramic glaze. These changes became more pronounced as the power increased. At the highest power setting (2.25 W), craters on the surface with large areas of melted or resolidified glaze surrounded by globules were visible. However, there was little to no exposure of ceramic crystals or visible regular surface roughening. Conclusions: Neither Er:YAG nor Nd:YAG dental lasers exhibited adequate surface modification for bonding of orthodontic brackets on glazed lithium disilicate ceramics compared with the control treated with 9.5% HF.


Gels ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 53
Author(s):  
Rayed Alyousef ◽  
Ahmed Abdel Khalek Ebid ◽  
Ghasan Fahim Huseien ◽  
Hossein Mohammadhosseini ◽  
Hisham Alabduljabbar ◽  
...  

Various geopolymer mortars (GPMs) as concrete repairing materials have become effective owing to their eco-friendly properties. Geopolymer binders designed from agricultural and industrial wastes display interesting and useful mechanical performance. Based on this fact, this research (experimental) focuses on the feasibility of achieving a new GPM with improved mechanical properties and enhanced durability performance against the aggressive sulfuric acid and sulfate attacks. This new ternary blend of GPMs can be achieved by combining waste ceramic tiles (WCT), fly ash (FA) and ground blast furnace slag (GBFS) with appropriate proportions. These GPMs were designed from a high volume of WCT, FA, and GBFS to repair the damaged concretes existing in the construction sectors. Flexural strength, slant shear bond strength, and compatibility of the obtained GPMs were compared with the base or normal concrete (NC) before and after exposure to the aggressive environments. Tests including flexural four-point loading and thermal expansion coefficient were performed. These GPMs were prepared using a low concentration of alkaline activator solution with increasing levels of GBFS and FA replaced by WCT. The results showed that substitution of GBFS and FA by WCT in the GPMs could enhance their bond strength, mechanical characteristics, and durability performance when exposed to aggressive environments. In addition, with the increase in WCT contents from 50 to 70%, the bond strength performance of the GPMs was considerably enhanced under sulfuric acid and sulfate attack. The achieved GPMs were shown to be highly compatible with the concrete substrate and excellent binders for various civil engineering construction applications. It is affirmed that the proposed GPMs can efficiently be used as high-performance materials to repair damaged concrete surfaces.


2021 ◽  
pp. 67-75

Eight historical textile objects belonging to the 16th-20th centuries in the collection of the Topkapi Palace Museum in Istanbul were analyzed with the purpose of reaching improved conservation and restoration methods. The historical textiles underwent dyestuff analysis by High Performance Liquid Chromatography, morphological and elemental analysis by Scanning Electron Microscope with energy Dispersive X-ray Spectroscopy, CIEL*a*b color measurement as well as technical analysis by optical microscopy.


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