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71.
Dong Wang Rongpei Shi Yufeng Zheng Rajarshi Banerjee Hamish L. Fraser Yunzhi Wang 《JOM Journal of the Minerals, Metals and Materials Society》2014,66(7):1287-1298
In this overview, we present integrated CAPHAD and phase-field modeling with critical experiments to explore a newly discovered, nonconventional, solid–solid phase transformation pathway based on the so-called pseudo-spinodal mechanism. We show that this new transformation pathway offers a new design strategy for Ti alloys with extremely fine and uniform α + β microstructures that could potentially have highly attractive balances of mechanical properties. To broaden the processing window for such a mechanism to operate, we also explore a different nonconventional transformation pathway that involves precursory phase separation. In addition, the variant selection process during the β → α transformation leading to macrozones is investigated and the results could shed light on how to control processing conditions to avoid or reduce microtexture at both the individual β grain level and the overall polycrystalline sample level. 相似文献
72.
Talukder Alam Pavani Kami Lingfei Cao Soumya Nag Colleen Bettles Xinhua Wu Rajarshi Banerjee 《Metallurgical and Materials Transactions A》2014,45(3):1089-1095
The onset of α nucleation in a carbon containing β-titanium alloy has been investigated by coupling atom probe tomography (APT) with transmission electron microscopy. The analysis of the APT results indicates that in addition to ω precipitates that can act as potential α nucleation sites, carbon atoms tend to form clusters within the β-matrix, which in turn give rise to additional nucleation sites for α, resulting in finer scale α precipitates due to increased nucleation density. 相似文献
73.
A. Ananthanarayanan S. A. Khot V. Jaiswal A. Joseph P. P. Songire D. Banerjee 《The International journal of environmental studies》2017,74(2):192-201
Ag loaded mordenite can be used as a trap for radio-iodine arising from nuclear reprocessing operations. Typically, iodine is trapped in the Ag loaded mordenite by the formation of AgI in the pores of the mordenite, through a solid-vapour reaction. In the presence of NOx and water vapour, AgI is most likely formed by liquid-vapour reaction between AgNO3 and I2. This reaction results in the formation of large aggregates of AgI crystals on the surface of the mordenite, also leading to a yellow colouration of the mordenite, which is not observed when NOx and water vapour is absent. 相似文献
74.
Making of a layered composite using two biopolymer gels with regularly aligned voids in the inner layer is described in this article. Calcium alginate constituted the inner layer, within which voids of 500 μm diameter were embedded in monolayer or in multiple layers using a fluidic device for bubbling. The chitosan without any additional crosslinker was used to form the outer layer. The layered structure enabled compartmentalization of drug hold-up, and differential release rates. These aspects were reviewed using bovine serum albumin and vitamin B12 as model solutes. The presence of voids at the inner layer of alginate increased the uptake, raising the level of absorptivity to more than 4000%. The composite film could hold two solutes at a time. The one, held inside the alginate layer started releasing only after 1 h of dipping in the release media. The adhesive strength between layers and the response of the composite film to compressive deformation are studied here. The effect of single or multiple layers of voids in the inner layer is reviewed. The slowing of degradation rate due to chitosan-encapsulation is experimentally determined. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47599. 相似文献
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76.
Abstract We discuss self-phase modulations and related transverse effects accompanying interaction of a light beam with a second harmonic radiation generated by it. Some experimental observations are explained by a simple perturbative approach. Numerical simulations provide a further insight into the nature of transverse self-effects in quadratically nonlinear media. An effective x (3)-like behaviour of dispersive quadratically nonlinear media is discussed. Such feature may lead to important consequences for measurements of the x (3) tensor in complex nonlinear media. 相似文献
77.
Experimental evidence of concurrent compositional and structural instabilities leading to ω precipitation in titanium-molybdenum alloys 总被引:1,自引:0,他引:1
A. DevarajS. Nag R. SrinivasanR.E.A. Williams S. BanerjeeR. Banerjee H.L. Fraser 《Acta Materialia》2012,60(2):596-609
The ω phase is commonly observed in many commercial β or near-β titanium alloys on rapidly cooling from the single β phase field and also during subsequent isothermal annealing. However, the crystallographic formation mechanism for the ω particles is hitherto unclear/under discussion. The present study primarily focuses on ω precipitation within the β (body-centered cubic (bcc)) matrix of simple model binary titanium-molybdenum (Ti-Mo) alloys. It provides direct experimental evidence of the formation of ω-like embryos from competing compositional and structural instabilities arising in the bcc lattice of Ti-Mo alloys during rapid cooling from the high-temperature single β phase field. The displacive partial collapse of the {1 1 1} planes of the parent bcc structure within compositionally phase-separated regions containing several at.% less of Mo, forming ω-like embryos, has been conclusively shown by coupling aberration-corrected high-resolution scanning transmission electron microscopy with atom probe tomography observations. Growth and coarsening of these ω-like embryos take place during subsequent isothermal annealing, accompanied with both a completion of the collapse of the {1 1 1} β planes leading to a fully developed ω structure as well as rejection of Mo from these precipitates, resulting in near-equilibrium compositions. 相似文献
78.
The Cr:Fe ratio (chromium-to-iron mass ratio) of chromite affects the production of chrome-based ferroalloys. Although the lit-erature contains numerous reports related to the magnetic separation of di... 相似文献
79.
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