scholarly journals Synthesis and Morphological Characterization of Nanoporous Aluminum Oxide Films by Using a Single Anodization Step

Coatings ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 115 ◽  
Author(s):  
Florencia Bruera ◽  
Gustavo Kramer ◽  
María Vera ◽  
Alicia Ares
Keyword(s):  
Aluminum Oxide ◽  
Pore Diameter ◽  
Morphological Characteristics ◽  
Morphological Characterization ◽  
Morphological Properties ◽  
Pore Density ◽  
Synthesis Conditions ◽  
Interpore Distance ◽  
Wide Range

Nanoporous anodic aluminum oxide (AAO) films play an important role in nanotechnology due to their easily adjustable morphological properties and wide range of applications. Thus, a deep and systematic characterization of the morphological properties of these coatings is essential. The most important variables in the synthesis of nanoporous AAO films include the anodization voltage, nature, concentration and temperature of the electrolyte, which, combined, result in pores of different sizes and geometries. In the present work, AA 1050 alloy was used to synthesize AAO films, using 0.3 and 0.9 M oxalic acid as the electrolyte and combining different electrolyte temperatures (20, 30 and 40 °C) and anodizing voltages (30, 40 and 60 V), with the aim to correlate the morphological properties of the coatings with the synthesis parameters of a single anodization step. The coatings obtained were characterized by optical microscopy and scanning electron microscopy, determining pore diameter, interpore distance, pore density and coating thickness. The results showed that, by varying the anodic synthesis conditions, it is possible to obtain coatings with a pore diameter between 21 and 97 nm, an interpore distance between 59 and 138 nm, pore density between 2.8 × 1010 and 5.4 × 109 pores/cm2 and thicknesses between 15 and 145 µm. In this way, the right combination of synthesis variables allows synthesizing AAO coatings with morphological characteristics best suited to each particular application.

Fabrication of Low Cost Membrane from Anodic Aluminum Oxide

2017 ◽  
Vol 751 ◽  
pp. 363-367
Author(s):  
Peerawith Sumtong ◽  
Apiluck Eiad-Ua
Keyword(s):  
Aluminum Oxide ◽  
Anodic Aluminum Oxide ◽  
Pore Diameter ◽  
Average Pore Diameter ◽  
Process Conditions ◽  
Low Grade ◽  
Pore Density ◽  
Average Pore ◽  
Anodic Aluminum ◽  
Interpore Distance

Anodic Aluminum Oxide (AAO) membrane has been successfully fabricated from two-step anodization with aluminum low grade (Al6061). The pore density, the pore diameter, and the interpore distance can be controlled by varying anodization process conditions. However, there are limits to control the mechanical strength and growth of AAO arrays, such as pore density, pore diameter and interpore distance. In this research the self-organized two-step anodization is carried out varying time at 24, 48 and 72 hours, respectively with 40V at the low temperature 2-5°C. The optimum conditions of AAO with two-step anodization is 40V for 48 hr. Finally, AAO substrate is separated from aluminum low-grade and enlarged pore diameter with pore widening process by 5% H3PO4. The physical properties were investigated by mean of field emission scanning electron microscope (FE-SEM) show that the average pore diameter and average interpore distance increase with the anodization time. Al6061 Aluminum substrate can be used to fabricate a nanoporous AAO film with an average pore diameter and average interpore distance larger than 70 and 90 nanometers, respectively but less mechanical stability.

scholarly journals Fabrication and geometric characterization of highly-ordered hexagonally arranged arrays of nanoporous anodic alumina

2014 ◽  
Vol 16 (1) ◽  
pp. 63-69 ◽  
Author(s):  
Wojciech J. Stępniowski ◽  
Agata Nowak-Stępniowska ◽  
Marta Michalska-Domańska ◽  
Małgorzata Norek ◽  
Tomasz Czujko ◽  
...  
Keyword(s):  
Aluminum Oxide ◽  
Anodic Aluminum Oxide ◽  
Pore Diameter ◽  
Theoretical Calculations ◽  
Anodization Voltage ◽  
Voltage Range ◽  
Nanoporous Anodic Alumina ◽  
Anodic Aluminum ◽  
Interpore Distance

Abstract Anodic aluminum oxide (AAO) has been fabricated in the 0.3 M oxalic acid at voltage range 20-60 V and temperature range of 35-50oC. The resulting nanoporous alumina surfaces were characterized by high resolution scanning electron microscopy, and the images were quantitatively analysed by means of an innovative approach based on fast Fourier transform. The influence of operating anodization voltage and electrolyte temperature on nanopores geometry (pore diameter, interpore distance, porosity, pores density) and arrangement has been studied in details and compared to literature data and theoretical calculations. It was found that independently from the temperature, the best arrangement of the nanopores is for anodic aluminum oxide formed at voltages ranging from 40 to 50 V. Moreover, it was found that pore diameter and interpore distance increase linearly with voltage, what is in line with the literature data.

scholarly journals Fabrication and characterization of highly ordered nanotubes of anodic aluminum oxide

2021 ◽  
pp. 9-13
Keyword(s):  
Aluminum Oxide ◽  
Anodic Aluminum Oxide ◽  
Pore Diameter ◽  
Nanometer Scale ◽  
Force Microscopy ◽  
Anodic Aluminum ◽  
Interpore Distance ◽  
Adhesion Sites ◽  
Atomic Force

Investigated the electrochemical synthesis and characterized of a nanometer scale porous anodic aluminum oxide (AAO) membrane with a mean pore diameter about of 80-100 nm. The anodizing process done by varying the anodizing temperature from 20 °C to 25 °C. The membranes exhibit interesting properties such as controllable pore diameters, periodicity and density distribution. These properties can preselect by adjusting the controlling parameters of a temperature-controlled two-step anodization process. The surface features of the nanometer scale membrane such as pore density, pore diameter and interpore distance were quantified using scanning electron microscopy (SEM) and atomic force microscopy (AFM). SEM and AFM investigations revealed the presence of focal adhesion sites over the surface of the porous membranes. The positive outcomes of the study, indicates that AAO membranes can used for applications in the future.

scholarly journals Influence of the anodization conditions and chemical treatment on the formation of alumina membranes with defined pore diameters

2021 ◽  
Author(s):  
Iwona Dobosz
Keyword(s):  
Aluminum Oxide ◽  
Chemical Treatment ◽  
Anodic Aluminum Oxide ◽  
Pore Diameter ◽  
Operating Conditions ◽  
Oxide Growth ◽  
Pore Density ◽  
Anodic Aluminum ◽  
Pore Widening ◽  
Oxide Membranes

AbstractPorous anodic aluminum oxide membranes were fabricated via two-step anodization of aluminum in 0.3 M H2C2O4, 0.3 M H2SO4 and 0.17 M H3PO4 solutions. The parameters of the oxide film such as: pore diameter (Dp), interpore distance (Dc), porosity (P) and pore density (ρ) can be completely controlled by the operating conditions of the anodization. Additionally, the pore diameters and pore density can be controlled via a chemical treatment (pore opening/widening process). The effect of anodizing conditions such as the applied voltage, type of electrolyte and purity of the substrate on the rate of porous oxide growth are discussed. The obtained results were compared with the theoretical predictions and data that has been reported in the literature. The influence of the duration of chemical etching on the structural features of the oxide membranes was studied. On the based on qualitative and quantitative FFT analyzes and circularity maps, it was found that the nanostructures of anodized aluminum have the maximum order under certain specified conditions. The presence of alloying elements affects not only the rate of oxide growth but also the morphology of the anodic aluminum oxide. The rate of oxide growth depends on the electrolyte type and temperature. During chemical treatment of the oxide films pore diameter increases with the pore widening time and the highest pore widening was observed in phosphoric acid solution.

scholarly journals Overview of Agaricus Subrufescens Strains used in the Last 15 Years in Brazil and other Countries and Current Potential Materials for the Future

2021 ◽  
Author(s):  
Diego Cunha Zied ◽  
Wagner G. Vieira Junior ◽  
Douglas M. M. Soares ◽  
Cassius V. Stevani ◽  
Eustáquio S. Dias ◽  
...  
Keyword(s):  
Internal Transcribed Spacer ◽  
High Weight ◽  
Morphological Characteristics ◽  
Morphological Characterization ◽  
Agaricus Blazei ◽  
Internal Transcribed Spacer Region ◽  
Commercial Use ◽  
Agaricus Subrufescens ◽  
Current Potential

Abstract The mushroom Agaricus subrufescens has been synonymous with Agaricus blazei and Agaricus brasiliensis during the last decades and there has been much discussion with regards to the origin, distribution, and nomenclature of this mushroom. Therefore, we conducted a genetic and morphological characterization of the mycelium and mushroom of four commercial strains currently cultivated in Brazil (ABL CS7, ABL 18/01, ABL 98/11, and ABL 16/01) together with an assessment of their agronomic behavior and compared these results with those of other strains used during the last 15 years. All the A. subrufescens strains characterized here are phylogenetically related to the Americas/Europe specimens, bearing an internal transcribed spacer region of type A (ABL 16/01) or both types A and B (ABL 18/01, ABL 98/11, and ABL CS7). We did not find any correlation between the morphological characteristics of the mycelial colonies and the agronomic behavior of the strains. Strains ABL 98/11 and ABL 16/01 produced the best yields and morphological characteristics for the mushrooms, indicating their high weight, which enhances the commercialization of the mushroom and justifies their longstanding commercial use over the last 15 years.

scholarly journals Morphological characterization of gram-positive and gram-negative bacteria from treated latex processing wastewater

2021 ◽  
Vol 1 (2) ◽  
pp. 32-36
Author(s):  
Farrah Aini Dahalan ◽  
Nor Azizah Parmin
Keyword(s):  
Oxygen Demand ◽  
Morphological Characterization ◽  
The Other ◽  
Morphological Properties ◽  
Morphological Observation ◽  
Gram Positive ◽  
Bacterial Colony ◽  
Gram Negative ◽  
Gram Staining

A preliminary morphological screening and isolation of bacterial colony from latex industrial wastewater was carried out. Bacteria colonies from latex processing wastewater were isolated from a local latex processing industry. It was found that 17 bacterial isolates had been purified grown on nutrient agar under 35˚C. The colonies were then purified and morphologically indicated via Gram staining and motility test. After morphological observation, it was identified that out of 17 isolates, 9 isolates were Gram positive and 8 isolates were Gram negative. There are 11 out of 17 colonies were rod-shaped bacterial colonies, while the other 6 colonies were cocci-shaped bacteria. There were 11 colonies of gliding bacteria, three colonies were non-motile bacteria and the other three colonies were flagellated bacteria. This study is only limited to morphological observation as the main aim of this study was to investigate the potential occurrence of viable growth in treated latex processing wastewater. The bacterial colonies were classified base on their morphological properties shown. This study has classified several genera such as Staphylococcus, Escherichia, Thiobacillus, Arthrobacter and other Genus. The growth curve of 17 isolates studied and the chemical oxygen demand were determined.

scholarly journals Genetic and Morphological Characterization of Mangifera indica L. Growing in Egypt

HortScience ◽  
2018 ◽  
Vol 53 (9) ◽  
pp. 1266-1270 ◽  
Author(s):  
Nader R. Abdelsalam ◽  
Hayssam M. Ali ◽  
Mohamed Z.M. Salem ◽  
Elsayed G. Ibrahem ◽  
Mohamed S. Elshikh
Keyword(s):  
Genetic Diversity ◽  
Mangifera Indica ◽  
Morphological Characteristics ◽  
Morphological Characterization ◽  
Molecular Techniques ◽  
Germplasm Management ◽  
Fruit Crops ◽  
The Family ◽  
High Diversity

Mango (Mangifera indica L.) is a fruit crops belong to the family Anacardiaceae and is the oldest cultivated tree worldwide. Cultivars maintained in Egypt have not been investigated previously. Mango was first brought to Egypt from South Asia. Morphological and molecular techniques were used to identify the genetic diversity within 28 mango cultivars. SSR and EST-SSR were used for optimizing germplasm management of mango cultivars. Significant variations were observed in morphological characteristics and genetic polymorphism, as they ranged from 0.71% to 100%. High diversity was confirmed as a pattern of morphological and genotypes data. Data from the present study may be used to calculate the mango relationship and diversity currently grown in Egypt.

Notes on some lesser known crickets of the tribe Podoscirtini (Podoscirtinae: Gryllidae: Orthoptera) from India 

Zootaxa ◽  
2020 ◽  
Vol 4821 (1) ◽  
pp. 49-70
Author(s):  
ASHOK KUMAR MEENA ◽  
RAJAMANI SWAMINATHAN ◽  
RAJENDRA NAGAR
Keyword(s):  
New Species ◽  
Morphological Characteristics ◽  
Morphological Characterization ◽  
Tropical Region ◽  
Two New Species

The present paper deals with a description of two new species of crickets of the subfamily Podoscirtinae (Orthoptera: Gryllidae), Trelleora khasiana sp. nov. and Indotrella maculata sp. nov., from India; besides, some additional morphological characteristics of the already reported species, Indotrella angusta Gorochov, 2003 is also presented. The morphological characterization of these two new species is supported with suitable line diagrams and plates. A checklist of crickets of Podoscirtinae for the Asia-tropical region is included.

scholarly journals Variability among selective guava (Psidium guajava L.) varieties revealed by morphology and RAPD marker

2018 ◽  
Vol 7 (2) ◽  
pp. 89-98 ◽  
Author(s):  
Farzana Alam ◽  
Kazi Didarul Islam ◽  
SM Mahbubur Rahman
Keyword(s):  
Random Amplified Polymorphic Dna ◽  
Rapd Marker ◽  
Scientific Information ◽  
Psidium Guajava ◽  
Morphological Characterization ◽  
Evolutionary Changes ◽  
Wide Range ◽  
The Difference ◽  
Range Of Variation

The research was conducted for the assessment of genetic diversity using both morphological and random amplified polymorphic DNA (RAPD) analysis of twelve guava (Psidium guajava L.) varieties growing in Bangladesh. Morphological characterization of guava varieties showed a wide range of variation. The highest variability was observed between Poly and Jelly varieties.Polymerase chain reaction with 5 arbitrary 10-mer and 3 arbitrary 12- mer RAPD primers produced a total of 50 bands of which 75.23 percent were polymorphic. The highest percentage of polymorphic loci (100%) was observed for primer A and the lowest (50%) for A03 primer. The UPGMA dendrogram revealed the segregation pattern and the difference of evolutionary changes. Guava varieties were separated into two main groups, one of them was made up of Chineese, Jelly, Kazi, Apple, L-49, Local-2 and Local-3. The other one was made up of Local-1, Poly, Kashi, Thai and Bombay. The highest genetic distance between Apple and Kazi peyara indicate that these varieties might be interesting in breeding programme for improving trait of interest. This scientific information could be used for further improvement of guava. Jahangirnagar University J. Biol. Sci. 7(2): 89-98, 2018 (December)

Characterization of pancreas-projecting rat dorsal motor nucleus of vagus neurons

2005 ◽  
Vol 288 (5) ◽  
pp. G950-G955 ◽  
Author(s):  
Kirsteen N. Browning ◽  
F. Holly Coleman ◽  
R. Alberto Travagli
Keyword(s):  
Morphological Characteristics ◽  
Input Resistance ◽  
The Body ◽  
Morphological Properties ◽  
Motor Nucleus ◽  
Electrophysiological Properties ◽  
Dorsal Motor Nucleus ◽  
Whole Cell Patch Clamp ◽  
Brain Stem Slices

The electrophysiological and morphological properties of rat dorsal motor nucleus of the vagus (DMV) neurons innervating the pancreas were examined by using whole cell patch clamp recordings from brain stem slices and postfixation morphological reconstructions of Neurobiotin-filled neurons. Recordings were made from 178 DMV neurons whose projections had been identified by previous apposition of the fluorescent neuronal tracer DiI to the body of the pancreas. DMV neurons projecting to the pancreas had an input resistance of 434 ± 14 MΩ, an action potential duration of 3 ± 0.1 ms, and an afterhyperpolarization of 18 ± 0.4 mV amplitude and 108 ± 7 ms time constant of decay; these electrophysiological properties resembled those of gastric-projecting neurons but were significantly different from those of intestinal-projecting neurons. Interestingly, 14 of 178 pancreas-projecting neurons showed the presence of a slowly developing afterhyperpolarization whose presence was not reported in DMV neurons projecting to any other gastrointestinal area. The morphological characteristics of pancreas-projecting neurons (soma area 274 ± 12 μm2; soma diameter of 25 ± 0.7 μm; soma form factor 0.74 ± 0.01; segments 9.7 ± 0.41), however, were similar to those of intestinal- but differed from those of gastric-projecting neurons. In summary, these results suggest that pancreas-projecting rat DMV neurons are heterogeneous with respect to some electrophysiological and morphological properties. These differences might underlie functional differences in the vagal modulation of pancreatic functions.

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