Search results for " Template"
showing 10 items of 89 documents
Ni-Based Alloy Nanostructured Electrodes for Alkaline Electrolyzers
In water alkaline electrolyzer field, the development of Nickel-based nanostructured electrode is one of the possible ways to improve the water electrolysis efficiency
Ruthenium Oxide Nanotubes Via Template Electrosynthesis
2011
Ruthenium oxide nanotubes were fabricated by a single-step galvanostatic deposition using porous anodic alumina membrane as template. For the electrodeposition process, we used a electrochemical cell specifically designed in order to employ only 0.5 ml of 0.02 M RuCl3•xH2O solution. The deposition from a very small volume was specifically addressed owing to the high cost of ruthenium compounds, which could be of some relevance from an applicative point of view. Several techniques were used to characterize the samples prior to and after thermal treatment, which was carried out at different temperatures in order to study the crystallization process of the deposit. Raman spectroscopy of as-dep…
Tin(IV) catalyzed D-galacturonic acid anomerization
2008
A comparative kinetic study of anomerization between the four main forms (alpha/beta-pyranosides and alpha/beta-furanosides) of D-galacturonic acid (GalAH(2), 1) and tin(IV) complexed D-galacturonate ([Sn(CH(3))(2)(GalA)(H(2)O)(2)], 2) in D(2)O, is reported. Important differences are shown by pD vs. mutarotation rate profiles of 1 and 2. Coordination, in fact, causes: i) a spectacular increase of the rate due to kinetic template assistance of the carboxylic tail holding the metal in close proximity to the reactive centre and ii) a change in the dependence of the rate on the pD. Entropic and enthalpic factors contribute to the huge activation energy decrease in 2. Anomerization rates of the …
Effect of temperature on the growth of alfa-PbO2 nanostructures
2010
Abstract Ordered arrays of α-PbO 2 nanostructures were grown by galvanostatic anodic deposition into the channels of alumina templates. Electrodepositions were performed in an aqueous solution containing lead acetate and sodium acetate at pH 5.4. Bath temperature and electrodeposition time were varied to check their effect on the growth of nanostructures. It has been found that filling of alumina pores is independent of the time and electrodeposition temperature, whilst height and growth kinetics of nanostructures vary with both parameters. Temperature greatly influences morphology: wires grown at room temperature consisted of clusters of particles, leading to poorly compact structures, whi…
Electrosynthesis of Ce–Co Mixed Oxide Nanotubes with High Aspect Ratio and Tunable Composition
2008
Cerium oxide and cobalt oxides have attracted the interest of several researchers due to their potential application in several technological fields electrochromism, lithium batteries, catalysis, etc.. Ceria has been used as a promoter in the so-called “three-way catalyst” for the control of toxic emission from automobile exhaust. The promotion consists of the enhancement of the noble metal dispersion, as well as stabilization of the supporting medium toward thermal sintering. 1,2 A direct catalytic effect of CeO2 in chemical processes such as water–gas shift reaction or NOx decomposition has been also evidenced. 3,4
Accelerating orthodontic tooth movement: a new, minimally-invasive corticotomy technique using a 3D-printed surgical template
2015
Background A reduction in orthodontic treatment time can be attained using corticotomies. The aggressive nature of corticotomy due to the elevation of muco-periosteal flaps and to the duration of the surgery raised reluctance for its employ among patients and dental community. This study aims to provide detailed information on the design and manufacture of a 3D-printed CAD-CAM (computer-aided design and computer-aided manufacturing) surgical guide which can aid the clinician in achieving a minimally-invasive, flapless corticotomy. Material and Methods An impression of dental arches was created; the models were digitally-acquired using a 3D scanner and saved as STereoLithography ( STL ) file…
Fabrication and Photoelectrochemical Behavior of Ordered CIGS Nanowire Arrays for Application in Solar Cells
2010
In this work, we report some preliminary results concerning the fabrication of quaternary copper, indium, gallium, and selenium CIGS nanowires that were grown inside the channels of an anodic alumina membrane by one-step potentiostatic deposition at different applied potentials and room temperature. A tunable nanowire composition was achieved through a manipulation of the applied potential and electrolyte composition. X-ray diffraction analysis showed that nanowires, whose chemical composition was determined by energy-dispersive spectroscopy analysis, were amorphous. A composition of Cu0.203In0.153Ga0.131Se0.513, very close to the stoichiometric value, was obtained. These nanostructures wer…
Anodic Alumina Membranes: From Electrochemical Growth to Use as Template for Fabrication of Nanostructured Electrodes
2022
The great success of anodic alumina membranes is due to their morphological features coupled to both thermal and chemical stability. The electrochemical fabrication allows accurate control of the porous structure: in fact, the membrane morphological characteristics (pore length, pore diameter and cell density) can be controlled by adjusting the anodizing parameters (bath, temperature, voltage and time). This article deals with both the fabrication and use of anodic alumina membranes. In particular, we will show the specific role of the addition of aluminum ions to phosphoric acid-based anodizing solution in modifying the morphology of anodic alumina membranes. Anodic alumina membranes were …
Aromatic N-oxide templates open inclusion and dimeric capsular assemblies with methylresorcinarene
2015
C2-2-methylresorcinarene forms host–guest complexes with pyridine N-oxide and quinoline N-oxide. In solution the NMR studies support the 1 : 1 host–guest complexes while in the solid state, the single crystal X-ray diffraction studies reveal dimeric capsule-like assemblies with 2 : 3 and 2 : 2 host–guest stoichiometry.
Constraints on Cosmic Strings Using Data from the Third Advanced LIGO–Virgo Observing Run
2021
We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 data set. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks and, for the first time, kink-kink collisions.cA template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension, $G\mu$, as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models.cAdditionally, we develop and test a third model which interpolat…