Search results for "Chromis"

Seasonal changes in size, sex-ratio and body condition of the damselfishChromis chromisin the central Mediterranean Sea

2014

Chromis chromisis one of the most abundant fish species on the Mediterranean rocky shores. Acting as a by-pass of nutrients from the pelagic to the rocky littoral system, it plays an important role as a resource provider and has a relevant function in the community assemblage.Chromis chromishas many of the characteristics required of an indicator species (e.g. it is easy to recognize in the field, small sized, widespread and abundant). In this study we focused on individual size, sex-ratio and body condition in a damselfish population occurring in a central Mediterranean marine protected area. Fishing trials on a monthly basis (April–November) allowed us to assess seasonal changes in popula…

SWEET IONIC LIQUIDS BASED MATERIALS FOR ENVIRONMENTAL APPLICATIONS

Thermochromic Thin Films: Synthesis, Properties and Energy Consumption Modelling

2013

Thermochromic materials such as vanadium dioxide have been postulated for use in “SMART” windows for a number of years. Such windows work by exploiting a structural phase change from an infra-red transmissive state to a infra-red reflective state. Significant challenges still remain before such materials will be able to find wide spread use. In this mini review we discuss the nature of this thermochromic transition with reference to the latest research work in the field. We pay particular attention to challenges such as film colouration, transition temperature, and transition hysteresis. We describe the most up to date strategies for addressing these challenges, considering advanced synthes…

Proton conducting composite electrolytes based on antimonic acid

1997

Abstract This report concerns a composite proton electrolyte suitable for use in electrochromic devices. The electrolyte consists of nanosize pyrochlore antimonic acid particles suspended in a poly(vinyl acetate) matrix by a gel route. It was found possible to substitute the antimonic acid by inert oxides of aluminum and silicon, thus making the electrolyte less harmful to the oxide electrodes of the electrochromic devices without considerably decreasing the conductivity. The proton conductivity of the antimonic acid electrolyte was ∼10 −4 S/cm at room temperature, practically independent of its amount of absorbed water.

Modulating the luminance of organic light-emitting diodes via optical stimulation of a photochromic molecular monolayer at transparent oxide electrode

2020

Nanoscale 12(9), 5444-5451 (2020). doi:10.1039/D0NR00724B

Solid state ionics and optical materials technology for energy efficiency, solar energy conversion, and environment control

1991

The fundamental electronic properties (including optical) of a solid are determined by the character of the interaction between its ionic and electronic subsystems. The state of the ionic subsystem can be changed persistently and reversibly by an external stimulus (current, light). The pertinent ion-controlled phenomena in the solids (solid electrolytes or mixed conductors) causes the ions to be inserted, extracted, transferred, or absorbed or transforms the states of the ions by redox reactions in the bulk or on the surface of the solid or on the interface of a (laminar or planar) solid ionic heterosystem. Several functions can be accomplished: (1) the optical response function of the soli…

Bis(pyridylvinyl)diaminobenzenes: synthesis, acidochromism and solvatochromism of the fluorescence

2005

Abstract C2-symmetrical 1,4-distyrylbenzenes with 4-dimethylaminobenzene or pyridine as terminal rings, and propyloxy or dipropylamino groups in the central 2,5-positions were prepared. Solvatochromism of the absorption is small, but more pronounced in the fluorescence spectra. Some compounds exhibit huge Stokes shifts. Acid strongly alters the fluorescence: red shifts and decreasing quantum yields is the general result, but depending on the position and character of the basic sites, a strong recovery of fluorescence efficiency combined with large hypsochromic shifts may result in highly acidic solutions.

Does the change in the length of the alkyl chain bring us closer to the compounds with the expected photophysical and biological properties? – Studie…

2022

The novel imidazole-based phenothiazine derivatives 3a-3e differing in the length of the alkyl chain at the imidazole substituents were effectively designed and synthesized. The effect of the alkyl chain on the photophysical properties of novel compounds was systematically investigated and supported by TD/DFT calculations. The photophysical characterization of 3a-3e compounds was performed in a series of solvents. Both absorption and fluorescence spectra exhibited positive solvatochromism. Phenothiazine derivatives 3a-3e have a noteworthy emission from blue to yellow region 450–600 nm, high quantum yields 41–93%, lifetimes in nanosecond scale (4.01–7.55 ns), and Stokes shifts in the range o…

Ultrafast Photo-Dynamics of a Reversible Photochromic Spiropyran

2002

We report the first ultrafast ring closure kinetics of the merocyanine (MC) of a reverse photochromic spiropyran 1‘,3‘,3‘-trimethyl-6,8-dinitrospiro[2H-1-benzopyran-2,2-indoline] (6,8-dinitro BIPS) and its 1‘-(2-carboxyethyl) substituted derivative. The reaction is fast and essentially over in a few hundred picoseconds. The rate of MC-S1 state decay evaluated from transient absorbance can be correlated directly with the MC-S1 state lifetime as determined using stimulated and ordinary emission measurements. The recovery of the MC-S0 state from MC-S1 has a component with a lifetime of 60−78 ps in acetonitrile with a second component of 350−470 ps probably due to a metastable intermediate. We …

Ground- and First-Excited-Singlet-State Electric Dipole Moments of Some Photochromic Spirobenzopyrans in Their Spiropyran and Merocyanine Form

2002

The dipole moments of four photochromic derivatives of indolinospirobenzopyran have been studied in their spiro and their open merocyanine form, in dioxane. Determinations have been done by electrooptical absorption measurements (EOAM). To prepare either a pure spiropyran or a pure merocyanine form solution, the experimental setup had to be modified by addition of a second light beam. In this way thermal equilibration between the spiropyran and the merocyanine form and switching from one form to the other induced by the measuring light beam could be avoided. The ground-state dipole moment of the spiro form amounts to (10−15) × 10-30 C m and increases strongly to about 60 × 10-30 C m with th…