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31.
Anjan Biswas Abhijit Bandyopadhyay Nikhil K. Singha Anil K. Bhowmick 《应用聚合物科学杂志》2007,105(6):3409-3417
In the present work, the metallocene‐based polyethylene–octene elastomer (POE) was chemically modified by solution grafting of acrylic acid in presence of benzoyl peroxide. The relative proportions of graft and gel formation were optimized through %weight gain, Fourier Transform infrared spectroscopy, elemental analysis and proton nuclear magnetic resonance spectroscopy. The gel formation in the POE matrix was found to be the prime competitor. The effect of grafting at its maximum level on various physicomechanical properties was thoroughly investigated, using X‐ray diffraction analysis, differential scanning calorimetry, mechanical, dynamic mechanical, and thermogravimetric analysis. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
32.
33.
Dev K. Mahato T. P. Sinha 《Journal of Materials Science: Materials in Electronics》2013,24(11):4399-4405
The polycrystalline praseodymium zinc zirconate Pr2ZnZrO6 (PZZO) is synthesized at 1,150 °C by means of solid state reaction technique. X-ray structural analysis confirmed the formation of a single phase monoclinic structure at room temperature. The nonzero intercept in the Nyquist plot indicates the presence of an arc for frequency higher than the maximum frequency measured (1 MHz). Comparative study of the impedance and modulus plot confirm the contribution from grain and grain-boundary and grain-boundary contribution dominates in the material. The activation energy of the compound calculated from imaginary part of impedance plot is found to be 0.442 eV which suggests that the polaron hopping is responsible for conduction mechanism in PZZO. Semiconducting behavior of the material is observed. Summerfield scaling shows a quite satisfying overlap of the data at different temperatures on a single master curve. 相似文献
34.
JP Gibbs G Murray L Risler JY Chien R Dev JT Slattery 《Canadian Metallurgical Quarterly》1997,57(24):5509-5516
Busulfan, a bifunctional alkylating agent, is a mainstay of myeloablative preparative regimens before hematopoietic stem cell transplantation. The apparent oral clearance of busulfan expressed relative to body surface area is 2-3-fold higher in children 1-4 years old than it is in adults. The first step in busulfan elimination is the formation of a tetrahydrothiophenium ion (THT+) in a glutathione S-transferase-catalyzed reaction. We present computer simulations that demonstrate that the ratio of the AUC of THT+ to that of busulfan over 6 h [(AUC(THT+)/AUC(BU))(0-->6)] is highly correlated (r2 = 0.805) with the determinants of THT+ formation and is virtually independent of the determinants of its elimination (r2 = 0.0201). We compared (AUC(THT+)/AUC(BU))(0-->6) determined in 14 children (0.5-4 years) to that of 11 adults (12-54 years) and found a 1.5-fold elevation in the area ratio (P = 0.0098) and a similarly significant increase in busulfan apparent oral clearance expressed relative to body surface area (P = 0.042). The only common explanation for the elevated busulfan apparent oral clearance and (AUC(THT+)/AUC(BU))(0-->6) is an enhanced ability of children to metabolize busulfan through glutathione conjugation. 相似文献
35.
Abhishek R. Indurkar Viraj D. Sangoi Nikhil D. Moon Mansingraj S. Nimbalkar 《IET nanobiotechnology / IET》2019,13(6):593
In this study, the synthesis of ultra‐fine grade antimony trioxide (Sb2 O3) using plant extract for the first time is reported. Antimony chloride was used as a starting material and Dioscorea alata tuber extract was used as a reducing and capping agent. The synthesised nanoparticles were characterised by X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy. XRD analysis indicates the formation of pure Sb2 O3 nanoparticles. The result from FE‐SEM and DLS showed that the particles have a cube‐like morphology and have an average size of 346.4 nm which falls within the range of ultra‐fine grade Sb2 O3.Inspec keywords: field emission electron microscopy, scanning electron microscopy, X‐ray diffraction, particle size, nanofabrication, light scattering, transmission electron microscopy, ultraviolet spectra, nanoparticles, antimony compounds, Fourier transform infrared spectraOther keywords: field emission scanning electron microscopy, FE‐SEM, dynamic light scattering, DLS, XRD analysis, antimony chloride, starting material, reducing agent, ultrafine grade antimony trioxide, plant extract, dioscorea alata tuber extract, capping agent, X‐ray diffraction, pure antimony trioxide nanoparticles, cube‐like morphology, Sb2 O3 相似文献
36.
37.
This paper presents the theory and performance of a differential induction machine, which is a special type of induction machine
having two shafts projected from the two ends of a single stator. Application of a differential load on the two shafts cause
them to run at different speed as a motor, which permits true differential movement and thus can meet the requirements of
a differential drive in an electric vehicle. The machine is also capable of regeneration in the differential mode. This paper
presents the construction of the above machine and performance of the same based on experimental results from a laboratory
prototype. The equivalent circuit of the motor has been presented and verified experimentally. 相似文献
38.
39.
Electron beam welding plays an important role in the aerospace industry where components like sensors,gears,actuators and air frames used in aircraft and rocket engines were welded using this technique.Welding is normally performed in a vacuum to avoid the scatter of electron due to the presence of gas molecules in the atmosphere and hence electron beam welding process provides the greater results.But still joining of dissimilar metals is challenging.This paper represents review of process,generation and distribution of heat source various input parameters,materials,microstructure,mechanical strength and the possibilities of joining dissimilar metals using electron beam welding. 相似文献
40.
Fei Chen Nikhil Gupta Rakesh K. Behera Pradeep K. Rohatgi 《JOM Journal of the Minerals, Metals and Materials Society》2018,70(6):837-845
Graphene-reinforced aluminum (Gr-Al) matrix nanocomposites (NCs) have attracted strong interest from both research and industry in high-performance weight-sensitive applications. Due to the vastly different bonding characteristics of the Al matrix (metallic) and graphene (in-plane covalent?+?inter-plane van der Waals), the graphene phase has a general tendency to agglomerate and phase separate in the metal matrix, which is detrimental for the mechanical and chemical properties of the composite. Thus, synthesis of Gr-Al NCs is extremely challenging. This review summarizes the different methods available to synthesize Gr-Al NCs and the resulting properties achieved in these NCs. Understanding the effect of processing parameters on the realized properties opens up the possibility of tailoring the synthesis methods to achieve the desired properties for a given application. 相似文献