This work aimed to evaluate the thermal and photo stability of the antioxidant potential (AP) of the Spirulina platensis biomass. Thermal stability was established at 25ºC, 40ºC and 50ºC for 60 days, in the dark, protected from light. Photo stability was evaluated using UV (15 W, λ = 265 nm) and fluorescent (20 W, 0.16 A, power factor FP > 0.5, 50/60 Hz, 60 lm/w, 1200 lm) light for 90 days in c...

One of the technological challenges for hydrogen sensors is long-term stability and reliability. In this article, the UV-light irradiation was introduced into the hydrogen sensing process based on water photolysis effect of Pt/WO3. Ascribing to that, fiber optic hydrogen sensor with Pt/WO3 nanosheets as the sensing element was demonstrated with significantly improved performance of stability. U...

Biodiesel consists of long chain fatty acid esters derived from vegetable oils, animal fats, and used oils. Biodiesel contains different types, amounts, and configurations of unsaturated fatty acids, which are prone to oxidation. Biodiesel stability is affected by its interaction with atmospheric oxygen, light and temperature, storage conditions, and factors causing sediment formation. It can b...

In this paper numerical results are reviewed ([13]) that demonstrate that common second-order operator-splitting methods can exhibit instabilities when integrating the Brusselator equations out to moderate times of about seven periods of oscillation. These instabilities are manifested as high wave number spatial errors. In this paper we further analyze this problem and present a theorem for sta...

We present accurate ground-state energies for the positronium atom in a Coulomb field of point charge Z (XPs!, for the positronium hydrogen ~HPs! and positronium lithium ~LiPs! atoms. Calculations are done using the diffusion quantum Monte Carlo ~DQMC! method. For XPs, the critical value of Z for binding is examined. While HPs is stable, the results show that LiPs is unstable against dissociati...

Ambient light stable 3-trifluoromethyl-3-aryldiazirine photolabels are developed via stabilization of the strained three membered diazirine ring by replacing the phenyl ring with electron withdrawing heterocyclic rings. Photolabeling studies reveal that these ambient light stable photolabels are equally efficient in photolabeling target proteins as the traditional 3-trifluoromethyl-3-phenyldiaz...

The effect of an electric field on a dilute suspension of asymmetric colloidal particles is to impose rotational order which can be detected as an induced birefringence in the sol. Furthermore, · if the particles are charged, such rotation is followed by electrophoretic translation. In a single apparatus, pulsed electric fields have been applied to sols of the rod-like clay mineral attapulgite,...

Rubber wood (Hevea brasiliensis) was esterfied with phenylisothiocyanate, and dimensional stability, decay resistance, and photo stability of the modified wood was assessed. The chemically modified wood was characterized by FTIR and CP/MAS C NMR spectroscopy. Unmodified and modified samples were exposed to a brown rot (Polyporus meliae) and a white rot (Coriolus versicolor) fungus for 12 weeks....

background numerous factors have an effect on the accuracy of an impression and resultant cast, and these include: impression material, impression technique, tray selection, impression disinfection, storage time of impression before pouring, stone type used for fabrication of cast. up to now, there has been little research conducted on the effect of contact time of a cast with an impression, on...