scholarly journals Electrochemically-Obtained Polysulfonic-Acids Doped Polyaniline Films—A Comparative Study by Electrochemical, Microgravimetric and XPS Methods

Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1050 ◽  
Author(s):  
Vladimir Lyutov ◽  
Varvara Kabanova ◽  
Oxana Gribkova ◽  
Alexander Nekrasov ◽  
Vessela Tsakova
Keyword(s):  
Structural Rearrangement ◽  
Disulfonic Acid ◽  
Polymer Backbone ◽  
High Doping Level ◽  
Long Term Storage ◽  
Polyaniline Films ◽  
Electrochemical Redox ◽  
Doped Polyaniline ◽  
Redox Switching

Polyaniline (PANI) layers are electrochemically obtained in the presence of four polysulfonic acids with different rigidities of the polymer backbone-iso-(and tere-)poly-(4,4′-(2,2′-disulfonic acid)-diphenylene-iso(tere)-phthalamide (i-PASA and t-PASA), polystyrenesulfonic acid (PSSA) and poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA). Combined microgravimetric (EQCM) and electrochemical measurements are carried out in the course of polymerization and repetitive redox switching. It is found that after synthesis PASA-doped PANIs shows good stability with low exchange of mass in the course of voltammetric scans, while PAMPSA-doped PANI contains a large amount of water that gradually becomes expelled in the repetitive redox switching. PANI obtained in the presence of PSSA takes an intermediate position with respect to mass exchanged in the electrochemical redox process. XPS studies are used to obtain data for the extent of doping of the different PANI materials. The results show high doping level (about 0.5) for PASA- and PAMPSA- and lower level (0.32) for PSSA-doped PANI layers. Repeated electrochemical studies carried out with the specimens investigated by XPS after long-term storage in the dry state give evidence for structural rearrangement, perfect recuperation of the initial electrochemical activity and high stability of the electrochemical response.

Preparation And elemental analysis of ancient fibers

1987 ◽  
Vol 45 ◽  
pp. 410-411
Author(s):  
Allen Angel ◽  
Kathryn A. Jakes
Keyword(s):  
Cross Sections ◽  
Physical Structure ◽  
Energy Dispersive ◽  
Archaeological Sites ◽  
X Ray ◽  
Long Term Storage ◽  
Backscattered Electron ◽  
Electron Imaging

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.

Modelling of Moisture Movement in Wood during Outdoor Storage

2001 ◽  
Vol 6 (2) ◽  
pp. 3-14 ◽  
Author(s):  
R. Baronas ◽  
F. Ivanauskas ◽  
I. Juodeikienė ◽  
A. Kajalavičius
Keyword(s):  
Experimental Data ◽  
Finite Difference ◽  
Climatic Conditions ◽  
Two Dimensional ◽  
Moisture Movement ◽  
Finite Difference Technique ◽  
Long Term Storage ◽  
Space Formulation ◽  
Term Storage

A model of moisture movement in wood is presented in this paper in a two-dimensional-in-space formulation. The finite-difference technique has been used in order to obtain the solution of the problem. The model was applied to predict the moisture content in sawn boards from pine during long term storage under outdoor climatic conditions. The satisfactory agreement between the numerical solution and experimental data was obtained.

Trehalose: a cryoprotectant that enhances recovery and preserves function of human pancreatic islets after long-term storage

Diabetes ◽  
1997 ◽  
Vol 46 (3) ◽  
pp. 519-523 ◽  
Author(s):  
G. M. Beattie ◽  
J. H. Crowe ◽  
A. D. Lopez ◽  
V. Cirulli ◽  
C. Ricordi ◽  
...  
Keyword(s):  
Pancreatic Islets ◽  
Human Pancreatic Islets ◽  
Long Term Storage ◽  
Term Storage

Humidity reliability of commercial flash memories for long-term storage

2020 ◽  
Vol 59 (SL) ◽  
pp. SLLC01 ◽  
Author(s):  
Tomoki Murota ◽  
Toshiki Mimura ◽  
Ploybussara Gomasang ◽  
Shinji Yokogawa ◽  
Kazuyoshi Ueno
Keyword(s):  
Flash Memories ◽  
Long Term Storage ◽  
Term Storage

Current situation with the core collection of spring triticale of the National Center of Plant Genetic Resources of Ukraine

2018 ◽  
pp. 75-85
Author(s):  
S.V. Chernobai ◽  
V.K. Riabchun ◽  
T.B. Kapustina ◽  
V.S. Melnyk ◽  
O.E. Shchechenko
Keyword(s):  
Genetic Resources ◽  
Plant Genetic Resources ◽  
Plant Production ◽  
Educational Institutions ◽  
Breeding Lines ◽  
Growing Season Length ◽  
Long Term Storage ◽  
Foreign Countries ◽  
Spring Triticale

Goal. To build up a spring triticale genetic bank to provide breeding, scientific and educational institutions with initial material and to preserve the existing diversity. To update the database of accessions with a set of valuable economic and morphological features. Results and discussion. The methodology and results of the collection formation and evaluation of spring triticale accessions in the National Center for Plant Genetic Resources of Ukraine of Plant Production Institute nd. a V. Ya. Yuriev are presented. The formed collection includes 1,935 accessions from 27 countries: 42 varieties and 1,478 breeding lines from Ukraine, 92 varieties and 248 lines from foreign countries and also 75 genetic lines. The collection was formed by major valuable economic features (plant height, growing season length, spike threshing, yield, 1000-grain weight, disease resistance, technological properties, etc.). Accessions with the majority of morpho-biological and valuable economic features were selected. All the accessions in the collection are certificated. 1,762 accessions were packed for storage into the National Depository; 1,507 of them were packed for long-term storage. Conclusions. The gene pool of spring triticale from the collection of the Gene Bank of Plants of Ukraine is widely used for breeding. This allows conducting hybridization of genetically and ecologically remote forms with various expressions of features and obtaining whole new breeding material. Involvement of collection accessions in breeding allows generating new genetic sources of valuable economic features.

Considerations of the technological quality assessment of sugarbeet

2011 ◽  
pp. 85-89 ◽  
Author(s):  
Giorgio Pezzi
Keyword(s):  
Quality Parameters ◽  
Northern Italy ◽  
Glucose Content ◽  
Long Term Storage ◽  
Interesting Correlation ◽  
Technological Quality ◽  
Thick Juice

No real improvement in the technological quality of beet has been recorded over the last 15 years in Northern Italy. Among the possible explanations for the quality stagnation is that the traditional formulae cannot correctly differentiate between sugarbeet varieties which produce thick juice of very high purity. This seems to be connected with the role of potassium. The use of a standard purification procedure gives reliable and accurate data which is immediately comparable with the factory data. Research projects on medium/long term storage are currently being performed by Co.Pro.B., Italy, in cooperation with Syngenta and Beta. Up to now the results have shown that storage of sugarbeet in autumn time in northern Italy is possible provided that suitable varieties and proper handling of the roots are employed. Results obtained in the storage trials are reported. Correlations have been found between quality parameters (purity, color and lime salts) of the purified juice with the glucose content of the raw juice. An interesting correlation is reported between purified juice purity and raw juice purity.

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