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81.
Glass and Ceramics - A catalyst was developed in the form of a composite based on a zeolite matrix modified with titanium nanoparticles based on zeolite raw materials from the Kulikovskoe deposit...  相似文献   
82.
Glass and Ceramics - The granulometric compositions of native and acid-activated rocks containing aluminosilicates are compared. It is shown that in water rocks gradually dissolve and the particle...  相似文献   
83.
Russian Engineering Research - Polymer samples based on polydicyclopentadiene produced from Russian dicyclopentadiene are investigated by thermogravimetric analysis and differential scanning...  相似文献   
84.
85.
Composites comprising Poly(Methyl Methacrylate) (PMMA) and CaCu3Ti4O12 (CCTO) via melt mixing followed by hot pressing were fabricated. These were characterized using X‐ray diffraction, thermo gravimetric, scanning electron microscopy, and Impedance analyzer for their structural, morphology, and dielectric properties. Composites were found to have better thermal stability than that of pure PMMA. The composite, with 38 Vol % of CCTO (in PMMA), exhibited remarkably low dielectric loss at high frequencies and the low frequency relaxation is attributed to the space charge polarization/MWS effect. Theoretical models were employed to rationalize the dielectric behavior of these composites. At higher temperatures, the relaxation peak shifts to higher frequencies, due to the merging of both β and α relaxations into a single dielectric dispersion peak. The AC conductivity in the high frequency region was attributed to the electronic polarization. POLYM. ENG. SCI., 54:551–558, 2014. © 2013 Society of Plastics Engineers  相似文献   
86.
Toughness of rigid thermoplastic is an important mechanical property in polymer technology. In the present study, toughening of waste polypropylene (WPP) with ethylene–propylene–diene monomer (EPDM) rubber at different loading levels was carried out by melt blending at 180 °C. The EPDM-toughened WPP samples were characterized for its thermo-mechanical properties. The effect of carbon black (5 wt%) as a functional filler in WPP/EPDM to impart UV protection was also studied. The test sheets were subjected to natural weathering in variable climatic conditions for a 4-month period of time and were taken out at regular intervals for characterization. The waste PP underwent excessive degradation as the mechanical strength properties such as tensile, flexural and impact strengths were reduced drastically. On the other hand, WPP containing varying proportions of EPDM and carbon black showed better retention of strength properties. The percentage degree of crystallinity has been unusually increased after the environmental degradation due to chemi-crystallization. The impact-modified WPP which contains carbon black retained the processability even after the environmental aging. After aging, the non-stabilized systems were shown extensive change, whereas the structural integrity has been well retained of the toughened WPP containing carbon black as was evident from SEM and optical photomicroscopy.  相似文献   
87.
Poorvasha  S.  Lakshmi  B. 《SILICON》2022,14(4):1479-1488
Silicon - This paper presents the analytical approximation of device physics of heterojunction based double gate (DG) Tunnel field effect transistors (TFETs) in terms of potential distribution,...  相似文献   
88.
Samal  Priyaranjan  Surekha  B.  Vundavilli  Pandu R. 《SILICON》2022,14(7):3317-3328
Silicon - Aluminum metal matrix composites (MMCs) exhibit promising mechanical properties that are potential materials for the aeronautical and automotive industries. In this study,...  相似文献   
89.
Metal Science and Heat Treatment - The nature of stability of dendritic microsegregation of rhenium in single crystals of intermetallic (γ′ + γ) alloys based on γ′-Ni3Al...  相似文献   
90.
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