scholarly journals The morphology of polyvinylpyrrolidone nanofibers containing Anredera cordifolia leaves

2021 ◽  
Vol 10 (2) ◽  
pp. 179-189
Author(s):  
Ida Sriyanti ◽  
Muhammad Rama Almafie ◽  
Yuda Prasetya Nugraha ◽  
Meutia Kamilatun Nuha Ap Idjan ◽  
Jaidan Jauhari
Keyword(s):  
Hydrogen Bonds ◽  
Chemical Analysis ◽  
Research Methods ◽  
Molecular Interaction ◽  
Electrospinning Process ◽  
Fiber Structure ◽  
Fiber Morphology ◽  
Electrospinning Method ◽  
Experiment Method ◽  
Physicochemical Structure

The electrospinning method has been used successfully to make polyvinylpyrrolidone nanofiber containing Anredera cordifolia leaves (BLE). The research methods used were qualitative and pure experiment method. Polyvinilpirolidone nanofibers containing BLE were prepared with three mass variations of the polyvinylpyrrolidone (% w/w), namely 12%, 10%, and 8% w/w, respectively. The results of the macroscopic photo show that the fiber structure looks white for PVP nanofibers and yellow for PVP/BLE nanofibers. The fiber morphology was analyzed using SEM and the results showed that PVP and all PVP/BLE nanofibers were like a continuous strand of crossbars with a diameter of 590 – 1190 nm. The decrease in the concentration of the PVP polymer led to a reduction in the diameter of the resulting nanofibers. The coefficients of variance (ε), of the PVP, BLE1, BLE2, and BLE3 nanofibers were 0.06, 0.09, 0.11, and 1.22, respectively. The physicochemical structure of the nanofibers was evaluated using XRD and FTIR. The chemical analysis (FTIR) showed that there was a molecular interaction between Anredera cordifolia leaves extract and polyvinylpyrrolidone in the form of hydrogen bonds. The physics analysis (XRD) shows the effect of the electrospinning process, which is to change the structure of BLE crystals to semi crystals. The application of PVP/BLE nanofiber for wounds dressing

scholarly journals Upward Needleless Electrospinning of Nanofibers

2012 ◽  
Vol 7 (2_suppl) ◽  
pp. 155892501200702 ◽  
Author(s):  
Haitao Niu ◽  
Xungai Wang ◽  
Tong Lin
Keyword(s):  
Electric Field ◽  
High Intensity ◽  
Electrospinning Process ◽  
Fiber Formation ◽  
Diameter Distribution ◽  
Fiber Morphology ◽  
Wire Surface ◽  
Elementary Method ◽  
Needleless Electrospinning ◽  
Electrospinning Method

Polyacrylonitrile (PAN) nanofibers were prepared by a needleless electrospinning method using three rotating fiber generators, cylinder, disc and coil. The effects of the spinneret shape on the electrospinning process and resultant fiber morphology were examined. The disc spinneret needed the lowest voltage to initiate fiber formation, followed by the coil and cylinder. Compared to cylinder, the disc and coil produced finer fibers with narrower diameter distribution. The productivity of a coil was 23 g/hr, which was much larger than that of the cylinder spinneret having the same length and diameter. Finite elementary method was used to analyze the electric field. Stronger electric field was found to be formed on disc and coil surface, which concentrated on the disc circumferential edge and coil wire surface, respectively. For cylinder, the high intensity electric field was mainly concentrated on the end area. Concentrated electric field on the fiber generating surface could be used to explain the better electrospinning performance of coil, which may form a new concept for designing needleless electrospinning spinnerets.

scholarly journals Research Regarding Physical Testing in the Military Pentathlon at the 50 M Race with Obstacles

2019 ◽  
Vol 24 (1) ◽  
pp. 29-37
Author(s):  
Ioan Sabin Sopa ◽  
Marcel Pomohaci
Keyword(s):  
Research Methods ◽  
Statistical Significance ◽  
Control Group ◽  
Military Students ◽  
Physical Test ◽  
Two Samples ◽  
Physical Testing ◽  
Experiment Method ◽  
The Military

Abstract The research started from the necessity of finding new ways to physical test the military students that are part of the military pentathlon 50 m race with obstacles team. The research methods used was the experiment method, using two groups: the first group was the control group and the second the experiment group. The experiment consisted in testing the students at: 50 m speed running, 800 m resistance running, push-ups, and specific testing like: 50 m swimming with obstacles, 8 km run in varied terrain. The results of our investigation showed that calculation of the statistical significance of the differences between the averages of the two samples showed significant values at p>0.05, n-1, at the following parameters: running 800 m (t = 2.71> 2.13 - p = 0.05); push-ups (t = 3.01> 2.95 - p = 0.05); freestyle swimming 50m (t = 2.81> 2.13 - p = 0.05).

scholarly journals Electrospun Nylon-6 Nanofibers and Their Characteristics

2020 ◽  
Vol 9 (1) ◽  
pp. 9-19
Author(s):  
Ida Sriyanti ◽  
Meily P Agustini ◽  
Jaidan Jauhari ◽  
Sukemi Sukemi ◽  
Zainuddin Nawawi
Keyword(s):  
Fiber Diameter ◽  
Peak Shift ◽  
Nylon 6 ◽  
Electrospinning Process ◽  
Electrospinning Technique ◽  
Fiber Concentration ◽  
Air Filters ◽  
Xrd Pattern ◽  
Electrospinning Method ◽  
Small Wave

The purposes of this research were to investigate the synthesized Nylon-6 nanofibers using electrospinning technique and their characteristics. The method used in this study was an experimental method with a quantitative approach. Nylon-6 nanofibers have been produced using the electrospinning method. This fiber was made with different concentrations, i.e. 20% w/w (FN1), 25% w/w (FN2), and 30% w/w (FN3). The SEM results show that the morphology of all nylon-6 nanofibers) forms perfect fibers without bead fiber. Increasing fiber concentration from 20% w/w to 30% w/w results in bigger morphology and fiber diameter. The dimensions of the FN1, FN2, and FN3 fibers are 1890 nm, 2350 nm, and 2420 nm, respectively. The results of FTIR analysis showed that the increase in the concentration of nylon-6 (b) and the electrospinning process caused a peak shift in the amide II group (CH2 bond), the carbonyl group and the CH2 stretching of the amide III group from small wave numbers to larger ones. The results of XRD characterization showed that the electrospinning process affected the changes in the XRD pattern of nylon-6 nanofiber (FN1, FN2, and FN3) in the state of semi crystal. Nylon-6 nanofibers can be used for applications in medicine, air filters, and electrode for capacitors

scholarly journals Electrospun Alginate Fibers: Mixing of Two Different Poly(ethylene oxide) Grades to Improve Fiber Functional Properties

Nanomaterials ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 971 ◽  
Author(s):  
Barbara Vigani ◽  
Silvia Rossi ◽  
Giulia Milanesi ◽  
Maria Bonferoni ◽  
Giuseppina Sandri ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Ethylene Oxide ◽  
Electrospinning Process ◽  
Mechanical Resistance ◽  
Fiber Morphology ◽  
Chain Entanglement ◽  
Poly Ethylene Oxide ◽  
Alginate Fibers ◽  
Poly Ethylene ◽  
Morphology And Mechanical Properties

The aim of the present work was to investigate how the molecular weight (MW) of poly(ethylene oxide) (PEO), a synthetic polymer able to improve alginate (ALG) electrospinnability, could affect ALG-based fiber morphology and mechanical properties. Two PEO grades, having different MWs (high, h-PEO, and low, l-PEO) were blended with ALG: the concentrations of both PEOs in each mixture were defined so that each h-PEO/l-PEO combination would show the same viscosity at high shear rate. Seven ALG/h-PEO/l-PEO mixtures were prepared and characterized in terms of viscoelasticity and conductivity and, for each mixture, a complex parameter rH/rL was calculated to better identify which of the two PEO grades prevails over the other in terms of exceeding the critical entanglement concentration. Thereafter, each mixture was electrospun by varying the process parameters; the fiber morphology and mechanical properties were evaluated. Finally, viscoelastic measurements were performed to verify the formation of intermolecular hydrogen bonds between the two PEO grades and ALG. rH/rL has been proved to be the parameter that better explains the effect of the electrospinning conditions on fiber dimension. The addition of a small amount of h-PEO to l-PEO was responsible for a significant increase in fiber mechanical resistance, without affecting the nano-scale fiber size. Moreover, the mixing of h-PEO and l-PEO improved the interaction with ALG, resulting in an increase in chain entanglement degree that is functional in the electrospinning process.

scholarly journals Different Molecular Interaction between Collagen and α- or β-Chitin in Mechanically Improved Electrospun Composite

Marine Drugs ◽  
2019 ◽  
Vol 17 (6) ◽  
pp. 318 ◽  
Author(s):  
Hyunwoo Moon ◽  
Seunghwan Choy ◽  
Yeonju Park ◽  
Young Mee Jung ◽  
Jun Mo Koo ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Tensile Strength ◽  
Regenerative Medicine ◽  
Hydrogen Bonds ◽  
Molecular Interactions ◽  
Molecular Interaction ◽  
Molecular Hydrogen ◽  
Correlation Spectroscopy ◽  
Two Dimensional ◽  
Secondary Interaction

Although collagens from vertebrates are mainly used in regenerative medicine, the most elusive issue in the collagen-based biomedical scaffolds is its insufficient mechanical strength. To solve this problem, electrospun collagen composites with chitins were prepared and molecular interactions which are the cause of the mechanical improvement in the composites were investigated by two-dimensional correlation spectroscopy (2DCOS). The electrospun collagen is composed of two kinds of polymorphs, α- and β-chitin, showing different mechanical enhancement and molecular interactions due to different inherent configurations in the crystal structure, resulting in solvent and polymer susceptibility. The collagen/α-chitin has two distinctive phases in the composite, but β-chitin composite has a relatively homogeneous phase. The β-chitin composite showed better tensile strength with ~41% and ~14% higher strength compared to collagen and α-chitin composites, respectively, due to a favorable secondary interaction, i.e., inter- rather than intra-molecular hydrogen bonds. The revealed molecular interaction indicates that β-chitin prefers to form inter-molecular hydrogen bonds with collagen by rearranging their uncrumpled crystalline regions, unlike α-chitin.

scholarly journals An openwork like structures of polylactide – manufacturing and properties

2018 ◽  
Vol 44 ◽  
pp. 00165 ◽  
Author(s):  
Karolina Sobczyk ◽  
Karol Leluk
Keyword(s):  
Lactic Acid ◽  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Weight Ratio ◽  
Electrospinning Process ◽  
Poly Lactic Acid ◽  
Process Conditions ◽  
Fiber Morphology

Poly(lactic acid) electrospinning tests were carried out under various process conditions. Openwork structures with a high surface area to weight ratio have been obtained. Changing the parameters of the PLA electrospinning process resulted in products with different fiber morphology.

scholarly journals Nanostructured Fibers Containing Natural or Synthetic Bioactive Compounds in Wound Dressing Applications

Materials ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2407 ◽  
Author(s):  
Alexa-Maria Croitoru ◽  
Denisa Ficai ◽  
Anton Ficai ◽  
Natalia Mihailescu ◽  
Ecaterina Andronescu ◽  
...  
Keyword(s):  
Wound Healing ◽  
Healing Process ◽  
Electrospun Nanofibers ◽  
Natural Compounds ◽  
Electrospinning Process ◽  
Wound Dressings ◽  
Wound Healing Process ◽  
Skin Substitutes ◽  
Bioactive Constituents ◽  
Electrospinning Method

The interest in wound healing characteristics of bioactive constituents and therapeutic agents, especially natural compounds, is increasing because of their therapeutic properties, cost-effectiveness, and few adverse effects. Lately, nanocarriers as a drug delivery system have been actively investigated and applied in medical and therapeutic applications. In recent decades, researchers have investigated the incorporation of natural or synthetic substances into novel bioactive electrospun nanofibrous architectures produced by the electrospinning method for skin substitutes. Therefore, the development of nanotechnology in the area of dressings that could provide higher performance and a synergistic effect for wound healing is needed. Natural compounds with antimicrobial, antibacterial, and anti-inflammatory activity in combination with nanostructured fibers represent a future approach due to the increased wound healing process and regeneration of the lost tissue. This paper presents different approaches in producing electrospun nanofibers, highlighting the electrospinning process used in fabricating innovative wound dressings that are able to release natural and/or synthetic substances in a controlled way, thus enhancing the healing process.

scholarly journals TiO2 NPs Assembled into a Carbon Nanofiber Composite Electrode by a One-Step Electrospinning Process for Supercapacitor Applications

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 899 ◽  
Author(s):  
Bishweshwar Pant ◽  
Mira Park ◽  
Soo-Jin Park
Keyword(s):  
Electrode Material ◽  
Carbon Nanofiber ◽  
Titanium Dioxide Nanoparticles ◽  
Scale Up ◽  
Carbon Composite ◽  
Electrospinning Process ◽  
Tio2 Nps ◽  
Electrospinning Method ◽  
One Step ◽  
Supercapacitor Applications

In this study, we have synthesized titanium dioxide nanoparticles (TiO2 NPs) into carbon nanofiber (NFs) composites by a simple electrospinning method followed by subsequent thermal treatment. The resulting composite was characterized by state-of-the-art techniques and exploited as the electrode material for supercapacitor applications. The electrochemical behavior of the as-synthesized TiO2 NPs assembled into carbon nanofibers (TiO2-carbon NFs) was investigated and compared with pristine TiO2 NFs. The cyclic voltammetry and charge–discharge analysis of the composite revealed an enhancement in the performance of the composite compared to the bare TiO2 NFs. The as-obtained TiO2-carbon NF composite exhibited a specific capacitance of 106.57 F/g at a current density of 1 A/g and capacitance retention of about 84% after 2000 cycles. The results obtained from this study demonstrate that the prepared nanocomposite could be used as electrode material in a supercapacitor. Furthermore, this work provides an easy scale-up strategy to prepare highly efficient TiO2-carbon composite nanofibers.

Electrochemical Performance of Li4Ti5O12/TiO2/Li0.4TiO2/C Composite Prepared by the Electrospinning Method Using as Lithium Battery Anode Material

2016 ◽  
Vol 852 ◽  
pp. 959-962 ◽  
Author(s):  
Chun Hua Chen ◽  
Jia Jia Feng ◽  
Wei Quan Shao ◽  
Sha Ou Chen ◽  
Li Zhu He ◽  
...  
Keyword(s):  
Electrochemical Impedance ◽  
Raw Materials ◽  
Electronic Conductivity ◽  
Specific Capacity ◽  
Impedance Spectra ◽  
Fiber Structure ◽  
X Ray Diffraction ◽  
Electrochemical Impedance Spectra ◽  
Electrospinning Method ◽  
Better Than

Li4Ti5O12(LTO) and Li4Ti5O12/TiO2/Li0.4TiO2/C (LTO/C) composite were prepared by the electrospinning method using acetic acid, ethanol, butyl titanate, lithium acetate and PVP (K90) as the raw materials. The phase structure and the morphology were characterized by the X-ray diffraction (XRD) and the scanning electron microscopy (SEM), respectively. It was found that the specific capacity was 356mAh/g at 0.5C for the composite, which was higher than the theoretical specific capacity of the pure Li4Ti5O12 due to the inclusion of other phase. Moreover, the C-rate performance for the composite was also better than that of the pure Li4Ti5O12 resulting from the formation of carbon-based fiber structure. Electrochemical impedance spectra (EIS) revealed that the composite exhibited the improved electronic conductivity than that of Li4Ti5O12.

scholarly journals Direct Deposition of Micron-Thick Aligned CeramicTiO2Nanofibrous Film on FTOs by Double-Needle Electrospinning Using Air-Turbulence Shielded Disc Collector

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
T. Krishnamoorthy ◽  
V. Thavasi ◽  
V. Akshara ◽  
A. Senthil Kumar ◽  
D. Pliszka ◽  
...  
Keyword(s):  
Tin Oxide ◽  
Electric Field Distribution ◽  
Electronic Devices ◽  
Electrospinning Process ◽  
Repulsive Force ◽  
Rotating Disc ◽  
One Dimensional ◽  
Air Turbulence ◽  
Electrospinning Method ◽  
Quantum Phenomena

One-dimensional (1D) metal oxides, typically nanowires and nanorods, have unique electronic and optical properties due to quantum phenomena that find applications in modern energy and electronic devices. We present here the electrospinning method that produces the aligned TiO2nanofibres directly on the fluorine-doped tin oxide (FTO) substrates mounted rotating disc collector. The aligned TiO2ceramic nanofibres mat of 6 μm thickness is achieved in 4 h using a nonconductive enclosed-air-shield with air-hood design over the FTO mounted rotating disc collector. The aligned TiO2nanofibers are found to retain its integrity and binding on FTO surface even after sintering at 500°C. SIMON 8 modeling package is used to determine the behaviour of the charged polymer/TiO2jet when single and double needles are used for electrospinning process. The simulation study reveals that the repulsive force of the charged fibers from the double needle exerts stronger electric field distribution along the flow of stream that results in the reduction of the fibers diameter, which is about 28 nm than that of using single-needle system.

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