نتایج جستجو برای: nitrogen inversion barrier

تعداد نتایج: 251299  

Amir Khacpai Hosein Abolghasemi, Hozhabr Sohbat zadeh Mohammad Ghannadi maragheh

In this paper, we studied effect of different parameters including density, viscosity, interfacial tension and solute transfer concentration on phase inversion hold-up. The results showed that change in phase density ratio had no effect on phase inversion hold-up. It also disclosed that the phase viscosity ratio was the most effective parameter affecting phase inversion hold-up and each phase h...

Journal: :Corrosion Science 2022

We report the role of ultrasonic shot-peening (SP) and laser-shock peening (LSP) on insertion atmospheric nitrogen during high temperature oxidation pure titanium improvement its resistance. Ion Beam analysis showed that for short durations, a layer Ti2N is formed at oxide-metal interface. However, only LSP treatment leads to formation long-term stable nitrogen-rich which acts as barrier diffus...

ژورنال: ژئوفیزیک ایران 2020
Mahjoobeh Meskaranian Peyman Pour Moghaddam

This study derives the discretized adjoint states full waveform inversion (FWI) in both time and frequency domains based on the Lagrange multiplier method. To achieve this, we applied adjoint state inversion on the discretized wave equation in both time domain and frequency domain. Besides, in this article, we introduce reliability tests to show that the inversion is performing as it should be ...

Journal: :Angewandte Chemie 2016
Romina Wechsel James Raftery Dominique Cavagnat Gilles Guichard Jonathan Clayden

Oligoureas (up to n=6) of meso cyclohexane-1,2-diamine were synthesized by chain extension with an enzymatically desymmetrized monomer 2. Despite being achiral, the meso oligomers adopt chiral canonical 2.5-helical conformations, the equally populated enantiomeric screw-sense conformers of which are in slow exchange on the NMR timescale, with a barrier to screw-sense inversion of about 70 kJ mo...

Journal: :Chemistry 2002
Peter Brandt Per-Ola Norrby Adrian M Daly Declan G Gilheany

The mechanism of alkene epoxidation by chromium(v) oxo salen complexes has been studied by DFT and experimental methods. The reaction is compared to the closely related Mn-catalyzed process in an attempt to understand the dramatic difference in selectivity between the two systems. Overall, the studies show that the reactions have many similarities, but also a few critical differences. In agreem...

Gravity data inversion is one of the important steps in the interpretation of practical gravity data. The inversion result can be obtained by minimization of the Tikhonov objective function. The determination of an optimal regularization parameter is highly important in the gravity data inversion. In this work, an attempt was made to use the active constrain balancing (ACB) method to select the...

Remnant magnetization causes a change in the direction and intensity of the magnetization vector. If inversion is performed regardless of remnance, in some cases it may have unreliable and misleading results. For inversion with respect to remnant magnetization, several solutions have been proposed so far, one of which is to convert the data of total magnetic field into data that is independent ...

2015
Dorian S. N. Parker Tao Yang Beni B. Dangi Ralf. I. Kaiser Partha P. Bera Timothy J. Lee

Meteorites contain bio-relevant molecules such as vitamins and nucleobases, which consist of aromatic structures with embedded nitrogen atoms. Questions remain over the chemical mechanisms responsible for the formation of nitrogen-substituted polycyclic aromatic hydrocarbons (PANHs) in extraterrestrial environments. By exploiting single collision conditions, we show that a radical mediated bimo...

Journal: :Nanoscale 2012
Danil W Boukhvalov Young-Woo Son

Based on first principles density functional theory calculations we explored energetics of oxygen reduction reaction over pristine and nitrogen-doped graphene with different amounts of nitrogen doping. The process of oxygen reduction requires one more step than the same reaction catalyzed by metals. Results of calculations evidence that for the case of light doped graphene (about 4% of nitrogen...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید