Several aromatic amino acid residues and haem resonances in the fully reduced form of Desulfovibrio gigas cytochrome c3 are assigned, using two-dimensional 1H n.m.r., on the basis of the interactions between the protons of the aromatic amino acids and the haem protons as well as the intrahaem distances known from the X-ray structure [Kissinger (1989) Ph.D. Thesis, Washington State University]. ...

Engine oils undergo oxidative degradation and wears out during service. Hence it is important to characterize ageing of engine oils at different simulated conditions to evaluate the performance of existing oils and also design new formulations. This work focuses on characterizing the thermo-oxidative degradation of synthetic and semi-synthetic engine oils aged at 120, 149 and 200 °C. Apparent a...

In order to study the thermal stability of accelerated-curing PF resin, the curing behavior of fresh PF resin was investigated in the presence of single accelerator of methylolurea derivatives (MMU), magnesium hydrate (Mg(OH)2), 25% aqueous solution of sodium carbonate (Na2CO3), and propylene carbonate (PC). Also their optimum combination was added in fresh PF resin. The thermal stability of cu...

Cyrtobagous salviniae Calder and Sands (Coleoptera: Curculionidae) is a successful biological control agent of aquatic weeds suppressing species like giant salvinia, Salvinia molesta D.Mitch. (Salviniales: Salviniaceae), in at least 15 countries over 3 continents (Julien et al. 2002). There are at least 2 ecotypes of this insect; the smaller Florida ecotype found on common salvinia, S. minima B...

The focus of energetic materials is on searching for a high-energy, high-density, insensitive material. Previous investigations have shown that 3D energetic metal-organic frameworks (E-MOFs) have great potential and advantages in this field. A nitrogen-rich E-MOF, Pb(bta)·2H₂O [N% = 31.98%, H₂bta = N,N-Bis(1H-tetrazole-5-yl)-amine], was prepared through a one-step hydrothermal reaction in this ...

A thermal behavior study of lipid-extracted Nannochloropsis gaditana (LEA) was performed in a thermogravimetric analyzer. The by heating the sample under different rates (5, 10, and 15 °C/min) from room temperature to 1000 °C using N2 gas as medium. This is crucial for stability studies kinetic control regime. following three stages chemical decompositions were found: (1) moisture removal (2) d...

in this paper, we intend to solve special kind of ordinary differential equations which is called heun equations, by converting to a corresponding stochastic differential equation(s.d.e.). so, we construct a stochastic linear equation system from this equation which its solution is based on computing fundamental matrix of this system and then, this s.d.e. is solved by numerically methods. mo...

Surface oxygen of oxide catalyst has low coordination number; they are negatively charged. can act active site for decomposition energetic nitramines (i.e. HMX). Additionally hydrous surface release OH radicals. Colloidal particles fulfil these requirements. Furthermore induce thermite reaction with aluminium particles. This study reports on the facile fabrication colloidal ferric 5 nm average ...

Thermal degradation behavior, exothermic patterns, and kinetic parameters of symmetrically/asymmetrically substituted polysilanes during the kumada thermal rearrangement in temperature range 100–450 °C, were investigated applying thermogravimetric (TGA) differential scanning calorimetric (DSC) techniques. Three kinds polysilanes, viz., Polydimethylsilane (PDMS), Polydiphenylsilane (PDPS) Polyme...

In this study, we show that adding halloysite nanotubes (HNT) to carbon black (CB)-packed acrylic rubber (ACM) composites improves their thermal properties. The thermo-oxidative stability, and dynamic mechanical properties of ACM (filled simply with 70 phr CB) hybrid comprising a fixed amount CB (60 phr) variable (2, 4, 6, 8, 10 were investigated. As evidenced by the oxidation induction time an...