scholarly journals Спектры электролюминесценции и структура анодного оксида алюминия при его формировании в химически чистой воде и спиртах

2021 ◽  
Vol 129 (3) ◽  
pp. 362
Author(s):  
Д.С. Овеченко ◽  
А.П. Бойченко

For a film of aluminum oxide (Al2O3) formed in distilled water (H2O), a linear growth was revealed during the high-voltage anodization time of 2000 s, and it was found that its electroluminescence (EL) is reliably recorded at an Al2O3 thickness of about 120 nm. It is shown that in DV and its deuterium-containing analogue, deuterium water (D2O), the electrolysis formation of Al2O3 is possible. cellular-nanoporous structure, identical to that formed in aqueous solutions of electrolytes. It was found that the presence of such a structure in the oxide is not a prerequisite for the generation of its EL. The EL spectrum of Al2O3 in H2O and D2O, as well as in “water-like” electrolytes: ethylene glycol, N, N-dimethylethanolamine, and isopentanol, was recorded for the first time. In the investigated range of 400–700 nm, significant differences in the luminescence in water and the above alcohols are revealed. For EL, the short-wavelength component with a wavelength of the order of 440 nm dominates in water, and in alcohols, the long-wavelength component with a maximum at 625 nm. In this case, nonstationarity of luminescence is observed both in the spectral composition and in the intensity of individual parts of the spectrum for the entire time of aluminum anodization.

RSC Advances ◽  
2016 ◽  
Vol 6 (29) ◽  
pp. 24142-24153
Author(s):  
Andreea S. Voda ◽  
Kevin Magniez ◽  
Nisa V. Salim ◽  
Cynthia Wong ◽  
Qipeng Guo

We report for the first time the use of Nα-Boc-l-tryptophan for the synthesis of amphiphilic BAB triblock copolymers for potential drug delivery applications.


1964 ◽  
Vol 41 (3) ◽  
pp. 499-511
Author(s):  
P. S. MEADOWS

1. A simple method is described for determining the substrate preferences of Corophium volutator (Pallas) and Corophium arenarium Crawford. 2. If offered a choice of its own substrate with that of the other species each prefers its own. 3. Level of illumination and colour of substrate have little effect on choice. An animal's size and hence its age has little effect on its substrate preferences. 4. C. volutator prefers a substrate previously maintained under anaerobic conditions, C. arenarium vice versa. 5. Treatments which kill, inactivate, or remove micro-organisms render sands unattractive to Corophium. These include boiling, acid-cleaning, drying, and soaking in fixatives or distilled water. Attempts to make these sands attractive again failed. 6. Distilled water, and solutions of the non-electrolytes sucrose and glycerol at the same osmotic pressure as sea water, induce many bacteria to desorb from sand particles; smaller numbers are desorbed in the presence of solutions of electrolytes at the same ionic strength as sea water (NaCl, Na2SO4, KC1, MgSO4, MgCl2, CaCl2). Of all these, only distilled water and solutions of MgCl2 and CaCl2 reduce the attractive properties of sands. Hence the loss of bacteria from the surface of sand grains, though related to the ionic strength and composition of the medium, is not necessarily associated with a substrate becoming unattractive.


2014 ◽  
Vol 50 (60) ◽  
pp. 8151-8153 ◽  
Author(s):  
N. Arjona ◽  
A. Palacios ◽  
A. Moreno-Zuria ◽  
M. Guerra-Balcázar ◽  
J. Ledesma-García ◽  
...  

AuPd/polyaniline was used for the first time, for ethylene glycol electrooxidation in a microfluidic fuel cell operated at room temperature.


2013 ◽  
Vol 832 ◽  
pp. 333-337 ◽  
Author(s):  
Zainovia Lockman ◽  
Dede Miftahul Anwar ◽  
Monna Rozana ◽  
Syahriza Ismail ◽  
Ehsan Ahmadi ◽  
...  

Anodic oxidation of titanium (Ti), zirconium (Zr) and niobium (Nb) foils in fluoride ethylene glycol (EG) added to it 1 H2O2 as oxidant was done to produce oxide film with nanostructures at 40 V. Whilst arrays of aligned nanotubes were successfully formed on the surface of Ti and Zr respectively, anodic Nb2O5 was found to consist of nanoporous structure with pore size of ~ 20 nm. Despite long nanotubes were formed on both Ti (2 μm) and Zr (3 μm), the surface of the nanotubes suffered from severe dissolution, thinning the wall and collapsing them. Well defined, ordered surface structure of the nanotubes is required as they will be used as template for subsequent deposition of nanoparticles. This was achieved when Ti anodised in 5 ml H2O2 fluoride EG. With excess H2O2 etching at the surface occur more uniformly forming homogenous surface structure. α-Fe2O3 were then electrodeposited on this surface at-3 V from chloride solution and the mode of formation is believed to be due to electrogeneration of base at the surface of the TiO2.


Nanomaterials ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 464 ◽  
Author(s):  
Sizhe Hu ◽  
Kai Jiang ◽  
Yuci Wang ◽  
Sui Wang ◽  
Zhongjun Li ◽  
...  

Carbon dots (CDs) with a room temperature phosphorescent (RTP) feature have attracted considerable interest in recent years due to their fundamental importance and promising applications. However, the reported matrix-free RTP CDs only show short-wavelength (green to yellow) emissions and have to be triggered by ultraviolet (UV) light (below 400 nm), limiting their applications in certain fields. Herein, visible-light-excited matrix-free RTP CDs (named AA-CDs) with a long-wavelength (orange) emission are reported for the first time. The AA-CDs can be facilely prepared via a microwave heating treatment of L-aspartic acid (AA) in the presence of ammonia and they emit unique orange RTP in the solid state with visible light (420 nm) excitation just being switched off. Through the studies of the carbonization process, the C=O and C=N containing moieties in the AA-CDs are confirmed to be responsible for the observed RTP emission. Finally, the applications of AA-CDs in information encryption and anti-counterfeiting were preliminarily demonstrated.


Author(s):  
R. A. Rooth ◽  
W. Hiemstra

Through rapid developments in fiber technology and data acquisition technology, pyrometry has become a successful tool for the measurement of gas turbine blade temperatures. The technology enables gas turbine owners and operators to monitor the blades and to optimise the exploitation of their assets in terms of efficiency and maintenance. With the application of thermal barrier coatings on turbine blades, pyrometry faces a new challenge as these coatings are not opaque at commonly used wavelengths. The application of TBC’s to protect the metal blades allows an increase of the firing temperature, increasing the efficiency of the installation, but is potentially an additional cause of locally overheating blades in the case the coating comes off. The present paper reports on the results of experimental work related to the temperature measurement on an in service Alstom 13E2 turbine with TBC coated first stage blades. Temperature measurements have been performed with both short- and long wavelength instruments (1 μm and 10 μm). The optical characteristics of ZrO2 material at a range of temperatures have been determined. These characteristics are important in the implementation of an algorithm that calculates the metal temperature from the temperature measurement results. These metal temperatures are of primary interest, This is the first time that experimental radiation temperature measurements on an industrial turbine, using both 1 and 10 μm technology, are reported. As the measurement trace over the turbine airfoil consists of areas on the blade that are covered with TBC as well as uncovered areas, a very interesting comparison on the merits of the various systems can be presented.


1975 ◽  
Vol 53 (19) ◽  
pp. 2110-2114 ◽  
Author(s):  
Richard A. Nolan

The phenomenon of self-parasitism in the aquatic phycomycetes has apparently been overlooked since it was first mentioned in the work of Klebs in 1899. This study documents fungal self-parasitism for the first time in Saprolegnia megasperma Coker (isolate 369A). The 369A isolate was grown for 48 h at 16 °C in shake cultures of a medium containing glucose, lactalbumin hydrolysate, phosphate, and micronutrients. The resulting vegetative growth was then transferred to shake-and-standing flasks at 16 °C and standing flasks at 4 °C containing either a dilute salts solution or double-distilled water to enhance the formation of both sexual and asexual structures. The results in both shake and standing cultures were comparable. When oogonia were produced in the absence of antheridial branches, the oospheres developed into normal oospores. When an antheridial branch was produced, an antheridial cell was never observed and the branch penetrated the oogonium via a pit and destroyed all or some of the oospheres (oospores?). This parasitic antheridial branch could reemerge from an oogonium via a pit and penetrate additional oogonia. The possible implications of self-parasitism for the relationship between S. megasperma and Saprolegnia unispora (Coker and Couch) Seymour are discussed.


2015 ◽  
Vol 51 (7) ◽  
pp. 1252-1254 ◽  
Author(s):  
Chao Lian ◽  
Fumin Ren ◽  
Yuxi Liu ◽  
Guofeng Zhao ◽  
Yongjun Ji ◽  
...  

Heterogeneous selective hydrogenation of ethylene carbonate to methanol and ethylene glycol, which provides an opportunity for industrial application of CO2 indirect conversion, was achieved for the first time over a copper chromite nanocatalyst.


RSC Advances ◽  
2014 ◽  
Vol 4 (81) ◽  
pp. 42965-42970 ◽  
Author(s):  
Lin Zhou ◽  
Xiaoxiao Li ◽  
Yong Wang ◽  
Mei Hong ◽  
Yongye Liang ◽  
...  

A monodisperse Pt/ceria hybrid with controlled nanoporous structure was fabricated with the aid of poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) microspheres as a hard template.


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