F. Musumeci

INFLUENCE OF THE PRESENCE OF ATRAZINE IN WATER ON THE IN-VIVO DELAYED LUMINESCENCE OF ACETABULARIA ACETABULUM

Abstract This article shows that the photoinduced delay luminescence in the seconds time range emitted from a unicellular alga Acetabuluria acetabulum is influenced in selective way by the presence of atrazine in the matrix. The presence of atrazine is noticeable up to a concentration of about 0.5 μg l −1 . The presented phenomenon suggests the possibility of analyzing trace elements in water, destined to be used for drinking, using a physical parameter related to a biological system and could make possible the development of a new methodology for monitoring water pollution.

Analogous features of delayed luminescence from Acetabularia acetabulum and some solid state systems

This paper compares some features of the delayed luminescence in the seconds range emitted from an unicellular alga Acetabularia acetabulum and from some solid state systems. Results lead us to think that such delayed luminescence is connected to the dimension of the ordered structures present in both biological and solid state systems. In particular, for the biological system examined, these structures are thought to be those which contribute to the dynamic formation of the cytoskeleton.

‘Simultaneous’ measurements of delayed luminescence and chloroplast organization in Acetabularia acetabulum

Abstract This paper reports results of ‘simultaneous’ measurements of chloroplast streaming and delayed luminescence of Acetabularia cells. We show that freezing in liquid nitrogen or incubation in chloroform affects significantly and rapidly both the organelle motility and delayed luminescence decay. Results suggest the idea that delayed luminescence is related to the integrity of the dynamic chloroplast organization.

Relation between delayed luminescence and functional state in soya seeds

SummaryThe possibility of using the parameters connected to delayed luminescence to detect thermal stress conditions in soya seeds is discussed here and the results of the measurement of photoinduced emission conducted on soya seeds characterized by a different vegetative vigour are presented. A phenomenological relationship between the total re-emission and the growth velocity was found. The distributions of the decay times relative to the different conditions of stress on the seeds have given indications towards the existence of different dynamics. On the basis of the results it seems that a correlation exists between the functional state of the seeds and delayed luminescence.

Impedance spectroscopy of pure water in the 0.01 Hz to 100 kHz range

SummaryThe complex impedance of a water-filled cell has been measured in the frequency range between 0.01 Hz and 100 kHz at temperatures ranging between 5°C and 80°C. The obtained results have been interpreted according to the Gouy, Chapmann and Stern model describing the water behaviour in the presence of electrode interfaces. The deconvolution of the measured complex impedance allowed to separate the contribution arising from the «bulk» water from those due to the Helmholtz layer and to the diffuse charge layer occurring at the electrode interface. The capacitance and resistance of the three layers are reported and their frequency and temperature dependences are briefly discussed. The use of this method as a tool to investigate the low-frequency dielectric properties of water is suggested.

Physical aspects of delayed luminescence inAcetabularia acetabulum

Delayed photo-induced luminescence has been studied inAcetabularia acetabulum individuals. The number of photons re-emitted when the wavelength, the intensity, or the duration of the incident radiation were varied are reported for 10 individuals. Reproducibility of the measurements in the same and in different individuals was good. The association between the incident radiation and photon re-emission was found to be non-linear. The relaitonship between the quantities involved in the phenomenon is discussed and a phenomenological equation describing the relationship is presented.

Comparison between time-of-flight measurements and numerical simulations for laser-generated plasmas

The modeling of laser-generated plasmas can be carried out by means of different theoretical approaches. Hydrodynamic simulations have the advantage of treating the plasma as a continuous fluid that expands in vacuum with a high Mach number. We used the analytical Anisimov model for the numerical simulations of a plasma expanding at supersonic velocities. The model describes the plume by means of a special solution of the gas dynamical equations on the hypothesis that the flow expands adiabatically. Here, we carry out a comparative analysis between experimental and numerical results: the model fits the experimental data for monoatomic plumes quite well. More specifically, the numerical data have been tested by comparing the time-of-flight signals obtained at the INFN-LNS in Catania from a pure metallic target. A Coulomb drift velocity was added to the expansion velocity, and only in this way was it possible to explain the experimental results, thus confirming the presence of self-generated electrostatic fields inside the expanding plasma plume.

The Liquid Crystalline Organism and Biological Water

The organism is a dynamic liquid crystalline continuum with coherent motions on every scale. Evidence is presented that biological (interfacial) water, aligned and moving coherently with the macromolecular matrix, is integral to the liquid crystallinity of the organism; and that the liquid crystalline continuum facilitates rapid intercommunication throughout the body, enabling it to function as a perfectly coherent whole

Activation Study of Implanted N+ in 6H-SiC by Scanning Capacitance Microscopy

Scanning Capacitance Microscopy has been used to determine the carr ier concentration profiles of N implanted 6H-SiC samples. The implantation dose and tar get temperature was chosen to avoid the formation of extended defects after annealing. Thermal t eatments were performed directly in a conventional furnace with a low ramp rate (0.05°C/s) and with a high ramp rate (200 °C/s). When performing high ramp rate thermal processes before the conv ntional furnace a higher activation occurs.

Temperature dependence of the ultraweak spontaneous photon emission from soya seeds

SummaryThe ultraweak radiation emitted from soya seeds during germination has been measured for different values of the temperature (20–35°C). The parameters relative to the photon emission time-counting series have been compared with the ones relative to germination and imbibition; it has been found that the activation energy relative to the process of the photon emission from live seeds is equal to that of the germination process (51 KJ/mole), demonstrating that the two processes are correlated. A function of the experimental parameters which eliminates the explicit dependence of the above biological processes on temperature has been proposed.