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REFERENCES 1. Partovi-Azar, P., Jand, S.P., Kaghazchi, P.: Electronic, Magnetic, and Transport Properties of Polyacrylonitrile-Based Carbon Nanofibers of Various Widths: Density-Functional Theory Calculations. Physical Review Applied 9 (2018) 014012. 2. Nataraj, S.K., Yang, K.S., Aminabhavi, T.M.: Polyacrylonitrile-based nanofibers—A state-of-the-art review. Progress in Polymer Science 37(2012) 487-513. 3. Bayramoğlu, G., Metin, A.Ü., Arıca, M.Y.: Surface modification of polyacrylonitrile film by anchoring conductive polyaniline and determination of uricase

., Yu, L., Chen, Y., Li, Y., (2014). Preparation, surface and pore structure of high surface area activated carbon fibers from bamboo by steam activation, Materials, 7, 4431-4441, DOI:10.3390/ma7064431. Tretsiakova-Mcnally, S., Joseph, P., (2018). Thermal and calorimetric evaluations of polyacrylonitrile containing covalently-bound phosphonate groups, Polymers, 10, 1-14, DOI:10.3390/polym1002013. Simitzis, J.C., Georgiou, P.C., (2015). Functional group changes of polyacrylonitrile fibres during their oxidative, carbonization and electrochemical treatment, J

, M. (2012) Engineering of Biomaterials, 15, 116-117, 100-103. [9] Mikołajczyk, T., Szparaga, G. (2009). Influence of fibre formation conditions on the properties of nanocomposite PAN fibres containing Nanosilver. Fibres and Textiles in Eastern Europe, 75(4), 30-36. [10] Mikołajczyk, T., Szparaga, G., Janowska, G. (2009) Influence of silver nano-additive amount on the supramolecular structure, porosity, and properties of polyacrylonitrile precursor fibers. Polymers for Advanced Technologies, 20(12), 1035-1043. [11] Houtz, R. C. (1950). “Orlon” acrylic fiber

Abstract:

Polyacrylonitrile (PAN) nanofibres and carbon nanotube (CNT) reinforced PAN nanofibres were successfully electrospun. A polymer plasticiser, ethylene carbonate (EC), was added into the PAN/CNT solutions. The average diameter of the fibres varied between 80 and 240 nm. This study investigated the effects of polymer concentration, CNT and EC on the morphological characteristics of electrospun PAN fibres. Electrospinning parameters were set at constant values to prevent their mutual influences on the resultant morphology. It was observed that increasing the polymer concentration led to a reduction of beads density and an increase in the diameter of the PAN nanofibres. The fibre diameters also increased as a result of the addition of CNTs below the electrical percolation threshold. It was found that the inclusion of EC permits changes in the morphological characteristic of the PAN/CNT nanocomposite fibre regardless of the effects of its conductivity and viscosity

optimal parameters and it requires not only the knowledge of chemistry and physics but also considerable experience. Polyacrylonitrile (PAN) is a well-known polymer with a good thermal stability and mechanical properties. Pure PAN and its copolymers have been widely studied for almost a century and various technological applications have been found for them [ 5 . Studies on nanomaterials are also connected with the development of textronics and e-textiles. A new generation of PAN fibers was elaborated (e.g. fibers with ceramic nanoparticles, such as silica

References [1] Huang X, Zeng Z, Fan Z, et al. Graphene-based electrodes, Advanced Materials, 2012, 24(45): 5979-6004. [2] Zhu Y, Murali S, Stoller MD, et al. Carbon-Based Supercapacitors Produced by Activation of Graphene, Science, 2011, 332(6037): 1537-1541. [3] Kim SY, Kim B-H, Yang KS, et al. Supercapacitive properties of porous carbon nanofibers via the electrospinning of metal alkoxide-graphene in polyacrylonitrile, Materials Letters, 2012, 87:157-161. [4] Ma C, Song Y, Shi J, et al. Preparation and one-step activation of microporous carbon nanofibers for

Abstract

The aim of this work is to describe a covalent immobilization of antibodies onto the poly- acrylamide-acrylonitrile or hybrid material UREASIL and creation of optical immunosensor for determination of aflatoxin Bl. For this purpose, mouse-anti-aflatoxin B1 antibodies with oxidized carbohydrate moieties were covalently immobilized on the membranes of polyacrylamide- polyacrylonitrile copolymer, as well as the hybrid material UREASIL. To determine the affinity> binding of the immobilized antibody with afatoxin Bl was used "sandwich" method. Associated with the immobilized antibody sought ingredients interact with a surplus of secondary’ signal antibodies. The described method has been developed as a model system, which can easily be applied for the determination of aflatoxins in samples of different origin. To the best of our knowledge, this is the first study to show that in the establishment of biosensor was used hybrid material UREASIL.

Abstract

Single cell supercapacitors with electrodes of varying amounts of graphene and carbon black, formed via the electrospinning process with a carbon-based Polyacrylonitrile (PAN), were tested in 1M H2SO4. From the tested samples, the overall data indicates no correlation between impedance and capacitance energy values. However, the breakdown of the various samples showed mixed results of; good correlations between lower impedance resulting in higher and lower capacitance; while other samples showed higher impedance correlating to both higher and lower capacitance. No correlation was observed between the Impedance value and the thickness of the samples. Furthermore, carbon mole content was not a major factor in determining impedance; therefore, structure is not a major contributor to impedance. Whereas, carbon mole content is a major contributor to capacitance energy; Hence, impedance provides an alternative control point to increasing energy (2-10X times), that can be retrofitted to existing systems, or to increase the energy storage beyond current levels by adjusting/controlling impedance in new designs. The data is indicating impedance is not constant and is varying. The mechanism of varying impedance is unclear and requires further research. However, it is thought to mimic the energy level and stability of matter (atoms). Therefore, impedance varies or oscillates accordingly to achieve an impedance level stability, and hence the term “Orbital Impedance Stability”. Thoughts into Impedance being an Energy Field, to be provided in next publication (In-sha’-ALLAH). This research is concluding that our conventional understanding of impedance is limited in scope. New approaches and further research is needed to better understand impedance behavior. A better understanding of impedance is essential to a breakthrough in energy storage devices from capacitors and batteries, to electric generation and distribution of energy, to magnetic levitation, medical drugs and other energy improvements.

Galvanic Wastewater Treatment by Means of Anionic Polymer Enhanced Ultrafiltration

This work is focused on polyelectrolyte enhanced ultrafiltration as an effective heavy metal separation technique. Three types of effluents, containing Zn(II), Cu(II) and Ni(II) ions, were subjected to the separation process. Poly(sodium 4-styrenesulfonate) - PSSS, a water soluble anionic polyelectrolyte was used as a metal binding agent. Two Sepa® CF (Osmonics) membranes: EW, made of polysulfone and a modified polyacrylonitrile membrane MW, were used in the ultrafiltration process. The preliminary UF tests were carried out on model solutions with target metal ion concentrations of 10, 100 and 250 mg dm-3. The main parameters affecting the metal retention (the polyelectrolyte quantity and solution pH) were examined. The values of pH 6 and polymer : metal concentration ratio CPSSS : CM = 7.5 : 1 (mol of mer unit per mol of metal) were selected to perform the galvanic wastewater ultrafiltration-concentration tests. Three types of wastewater containing Zn(II), Ni(II) and Cu(II) ions within the concentration range of 30÷70 mg dm-3 were used in the investigations. Very high metal retention coefficients, up to > 99%, were achieved. The retentates obtained were subjected to the decomplexation-ultrafiltration (pH = 1) and subsequent diafiltration step, which enabled partial recovery of concentrated metal ions and the polyelectrolyte. The recovered polyelectrolyte was reused toward Ni(II) ions and the high effectiveness of metal separation has been achieved.

References [1] Smit, E., Buttner, U., Sanderson, R. D. (2010). Nanofibers and Nanotechnology in Textiles. (Brown, P. J., Stevens, K. eds.). Woodhead Publishing Limited (Cambridge). [2] Moon, S., Farris, R. J. (2009). Strong Electrospun Nanometer-Diameter Polyacrylonitrile Carbon Fiber Yarns. Carbon, 47, 2829-2839. [3] Lotus, A. F. (2009). Synthesis of Semiconducting Ceramic Nanofibers, Development of P-N Junctions and Bandgap Engineering by Electrospinning. Ph.D. Thesis, The University of Akron, Graduate Faculty, Ohio, USA. [4] Ali, U., Zhou, Y., Wang, X., Lin, Y