Electron transfer between electronically excited states and electron donors or acceptors in the ground state has been established as an important mechanism for the quenching of excited states. The paper of Rehm and Weller [1], demonstrating for several aromatic excited singlets and numerous aromatic quenchers in acetonitrlle a clear-cut correlation between the quenching rate constant kq and the...

Article history: Received: 23.12.2013. Received in revised form: 15.01.2014. Accepted: 15.01.2014. Subcritical austenite reverse transformation quenching was used to improve the mechanical properties of 30CrMnSi steel, and the microstructure and mechanical properties of the samples were analyzed by subcritical austenite reverse transformation quenching. Experimental results show that subcritica...

Understanding and resolving the mechanisms that affect the photoluminescence (PL) of Si QDs are of great importance because of their strong potential for optoelectronic and solar cell materials. In this article, the intrinsic exciton dynamics of water-dispersed allylamine-functionalized silicon quantum dots (Si QDs) have been explored as a function of temperature by means of steady-state and ti...

The metal-to-ligand charge transfer (MLCT) excited states of two related heteroleptic Ru(ii) compounds [Ru(bpy)2(deeb)](2+) and [Ru(bpy)2(deebq)](2+), where bpy is 2,2'-bipyridine, deeb is 4,4'-(CO2CH2CH3)2-2,2'-bipyridine and deebq is 4,4'-(CO2CH2CH3)2-2,2'-biquinoline, were characterized in fluid acetonitrile by temperature dependent photoluminescence spectroscopies as well as quenching by io...

objective(s):the objective of this study was to investigate the interaction of daunorubicin (dnr) and cardiac myosin (cm) and the changes in mice hearts to exhibit dnr-induced cardiotoxicity . materials and methods:the interaction between dnr and cm was expressed using fluorescence quenching at ph 4.0-9.0 and 15-37 °c. dnr-induced cardiotoxicity was studied using in vivo experiment.  forty grou...

In This research, gold nanoparticles were synthesized and functionalized by the antibody of aflatoxins. The quenching of the fluorescence of excitation emission matrices (EEM) of two type of aflatoxins (B1, G1), provoked by the gold nanoparticles, was studied by principal component analysis (PCA) and multivariate curve resolution with alternating least squares (MCR-ALS). These aflatoxins show q...

curcumin (cur) is the active curcuminoid with many physiological, biochemical, and pharmacological properties. solubility and stability of cur is the limiting factors for realizing its therapeutic potential. bovine β-casein is an abundant milk protein that is highly amphiphilic and self-assembles into stable micellar nanoparticles in aqueous solution. β-casein nanoparticle can solubilize cur mo...

An appealing definition of the term "molecule" arises from consideration of the nature of fluorescence, with discrete molecular entities emitting a stream of single photons. We address the question of how large a molecular object may become by growing deterministic aggregates from single conjugated polymer chains. Even particles containing dozens of individual chains still behave as single quan...

the aggregation behavior of anionic cobalt(ii) 4,4′,4ʺ,4‴-tetrasulfonated phthalocyanine, [co(tspc)4-] was studied at its various concentrations and different ionic strengths using optical absorption and resonance light scattering (rls) spectroscopies in 5 mm phosphate buffer, ph 7.0 at 25 °c. the results show no aggregation behavior at concentration range of 5.1 × 10-6-7.5 × 10-5 m. also, the ...