Search results for "METALS"
showing 10 items of 2013 documents
Environmental impact assessment on the Monza cathedral (Italy): A multi-analytical approach
2020
This research deals with the characterization of black crusts collected from the Dome of Monza (Milan, Italy). Air pollution is responsible for the degradation of historical buildings surfaces. In urban and industrial areas, the degradation process is accelerated, due to carbonaceous particles and heavy metals emitted by combustion processes which contribute to the formation of black crust (BCs). In this study the characterization of BC was performed using different analytical techniques such as: HRSEM-EDX, IC, LA-ICP/MS and digital image analysis. In particular, the research focused on the study of "heavy metals" which contribute to the identify the main sources of pollution responsible fo…
Infection of Soybean Plants with the Insect Bacterial Symbiont Burkholderia gladioli and Evaluation of Plant Fitness
2017
To investigate the establishment and consequences of host-microbe interactions, it is important to develop controlled infection assays suitable for each system, as well as appropriate methods to evaluate successful infection and its associated effects. Here, we describe a procedure for bacterial inoculation of soybean plants, followed by the assessment of systemic infection and impact on plant fitness. Soybean (Glycine max) seedlings were mechanically wounded using a device that mimics insect herbivory and inoculated with known cell numbers of Burkholderia gladioli bacteria previously isolated from an insect host. The impact on the plants was evaluated by monitoring changes in height, time …
Laser heterodyne displacement measuring using PLZT frequency shifter
1991
Abstract The implementation of a frequency shifter based on lead lanthanum zirconate titanate ceramic (PLZT) and a voltage-controlled λ/4 plate is described. The capabilities of these elements are demonstrated with results from a Michelson-type laser heterodyne displacement measuring interferometer with 0.01 μm accuracy and 1 Hz display update rate.
Electrochemical formation of N,N′-diarylhydrazines by dehydrogenative N–N homocoupling reaction
2020
Hydrazines represent a class of compounds of high interest due to their applicability as versatile starting materials in many important transformations. Herein, we report a synthetic approach to hydrazine derivatives using commercially available anilines and an anodic dehydrogenative N-N coupling reaction as the key step.
Optimization of ZnO:Al/Ag/ZnO:Al structures for ultra-thin high-performance transparent conductive electrodes
2012
Al-doped ZnO (AZO)/Ag/AZO multilayer coatings (50-70 nm thick) were grown at room temperature on glass substrates with different silver layer thickness, from 3 to 19 nm, by using radio frequency magnetron sputtering. Thermal stability of the compositional, optical and electrical properties of the AZO/Ag/AZO structures were investigated up to 400 °C and as a function of Ag film thickness. An AZO film as thin as 20 nm is an excellent barrier to Ag diffusion. The inclusion of 9.5 nm thin silver layer within the transparent conductive oxide (TCO) material leads to a maximum enhancement of the electro-optical characteristics. The excellent measured properties of low resistance, high transmittanc…
In-situ annealing characterization of atomic-layer-deposited Al2O3 in N2, H2 and vacuum atmospheres
2019
Tarkista embargo, kun artikkeli julkaistu. Atomic-layer-deposited Al 2 O 3 films can be used for passivation, protective, and functional purposes in electronic devices. However, as-deposited, amorphous alumina is susceptible to chemical attack and corrosion during manufacturing and field-use. On the contrary, crystalline Al 2 O 3 is resistant against aggressive chemical treatments and corrosion. Here, high-temperature treatments in N 2 , H 2 , and vacuum were used to crystallize alumina which exhibited different crystalline phases. The annealing process was monitored continuously in situ by measuring the film temperature and surface reflectance to understand the crystallization kinetics. Ex…
High-pressure study of the aurophilic topological Dirac material AuI
2022
We endeavour to explore the high-pressure study in the aurophilic AuI within the state-of-the-art of first principles. The impediment of expressing precise ground-state features of aurophilic compounds that had afflicted prior theoretical research has been resolved by incorporating van der Waals corrections (vdw). Mechanical and dynamical stability are ensured at ambient using the computed elastic constants and phonon dispersion curves. The dynamical instability is triggered by the application of pressure in AuI, as evidenced by the softening of an acoustic mode (Eu) at ∼7 GPa. Non-adherence of estimated elastic constants to the Born stability criterion at this pressure illustrates the syst…
Thermal activated carrier transfer between InAs quantum dots in very low density samples
2010
In this work we develop a detailed experimental study of the exciton recombination dynamics as a function of temperature on QD-ensembles and single QDs in two low density samples having 16.5 and 25 dots/¼m2. We corroborate at the single QD level the limitation of the exciton recombination time in the smallest QDs of the distribution by thermionic emission (electron emission in transient conditions). A portion of these emitted carriers is retrapped again in other (larger) QDs, but not very distant from those emitting the carriers, because the process is limited by the diffusion length at the considered temperature.
Effect of the Alkaline Cations on the Stability of the Model Polynucleotide Poly(dG-dC)·Poly(dG-dC)
2011
When the model polynucleotide poly(dG-dC)∙poly(dG-dC) [polyGC] is titrated with a strong acid (HCl) in unbuffered aqueous solutions containing the chlorides of the alkali metals in the concentration range 0.010 M-0.600 M, two transitions in the absorbance vs. pH plots are evidenced, characterized by the constants pK(a(₁)) and pK(a(₂)). The limiting values at infinite saline concentrations of these two constants, namely pK(∞)(a(₁)) and pK(∞)(a(₂)) obtained making use of the "one site saturation constant" equation or, in turn, of the double logarithmic plot: pK(a) vs. log([salt]⁻¹), exhibit a clear dependence on the nature of the cations. The effects of the different alkali cations on the pK(…
Response of soil bacterial community structure to successive perturbations of different types and intensities
2008
SummaryIn soil, genetic structure modifications of indigenousbacterial community consecutively to a severe stress(mercury contamination) were delayed when thecommunity was pre-exposed to various minor per-turbations (heat, copper and atrazine). Such minorperturbations induced transitory community struc-ture modifications leading to an increase of commu-nity stability towards a severe mercury stress. Theseresults illustrated well the short-term pre-adaptationprocess for bacterial community hypothesizing thatcommunity submitted to perturbations become moreresistant to withstand another stress. Compared with other environmental matrices of the bio-sphere, soils are considered as the main reservo…