Fluorescent clusters of several Ag atoms are fluorophores with a large set of attractive properties including sub-nanometer size, high fluorescence quantum yield and large Stokes shift. When formed on polymeric scaffolds they exhibit a broad range of heterogeneities in excitation and emission spectra. Addressing this issue we provide detailed spectroscopic studies of these clusters produced by ...

Fluorescence excitation-emission matrix (EEM) spectroscopy coupled with parallel factor analysis (PARAFAC) is an established tool of organic matter fingerprinting in aqueous systems. Recently, EEMPARAFAC has been successfully applied in drinking water treatment for simple, rapid, and sensitive evaluation of organic matter removal during different treatment processes. This review describes some ...

We study a system of two interacting, non-indentical quantum emitters driven by coherent field. focus on the particular condition two-photon resonance and obtain analytical expressions for stationary density matrix observables fluorescent emission. Importantly, our are valid general situation non-identical with different transition energies. Our results allow us to determine regime parameters i...

A weighted parallel factor analysis (W-PARAFAC) model is applied to excitation-emission matrix (EEM) fluorescence spectra of carbamate pesticides to aid with calibration in the presence of Raman scattering. Traditional PARAFAC inefficiently models the Raman scattering, resulting in prediction and calibration errors when a significant background is present. Four different weighting strategies we...

We present here three-dimensional time-wavelength-intensity displays of changes in variable fluorescence, during the O(JI)PSMT transient, observed in cyanobacterium at room temperature. We were able to measure contributions of individual chromophores to fluorescence spectra at various times of fluorescence induction (FI). The method was applied to a freshwater cyanobacterium, Synechococcus sp. ...

In evaluating the autofluorescence properties of normal and diseased skin we discovered that psoriatic plaques can emit a distinct red fluorescence when illuminated with UVA or blue light. Using a macrospectrofluorometer equipped with a 442 nm excitation laser, a sharp in vivo fluorescence emission peak around 635 nm could be demonstrated within the plaques of 34 of 75 (45%) patients with psori...

Optical methods for the detection of carious lesions, calculus and plaque have the advantage of being minimally invasive. The use of endogeneous fluorescence markers like porphyrins could simplify the application of fluorescence techniques in the dental practice. It is known that porphyrins are produced by some of the bacterial species that are present in the oral cavity. Since porphyrins have ...

Ž . Wide bandgap semiconductors such as diamond and the III–V nitrides GaN, AlN, and AlGaN alloys exhibit small or even negative electron affinities. Results have shown that different surface treatments will modify the electron affinity of Ž . diamond to cause a positive or negative electron affinity NEA . This study describes the characterization of these surfaces Ž . with photo-electron emiss...

Fluorescence quenching of the fluorescence is a useful method to determine copper complexing properties of the dissolved organic matter. This technique provides express results often by choosing one or two excitation-emission fluorescence measurement for a straight range of concentration. That why it is not representative of the whole sample. On another hand, using total luminescence spectra gi...

Dissolved organic matter (DOM) plays a non-negligible role in the indirect photodegradation of contaminants. This research investigated roles DOM and environmental factors (salinity, pH, NO 3 ? , HCO ) ofloxacin (OFX) simulated seawater. Results showed that can significantly accelerate OFX, 1 O 2 * were main reactive intermediates (RIs) could promote OFX. Fluorescence excitation–emission matrix...