scholarly journals Electrospinning of Ultrafine Conducting Polymer Composite Nanofibers with Diameter Less than 70 nm as High Sensitive Gas Sensor

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1744 ◽  
Author(s):  
Qianqian Zhang ◽  
Xiaoxiong Wang ◽  
Jie Fu ◽  
Ruiqiang Liu ◽  
Hongwei He ◽  
...  
Keyword(s):  
Composite Nanofibers ◽  
Fiber Diameter ◽  
Average Diameter ◽  
Impedance Analysis ◽  
Ultrafine Fibers ◽  
Ammonia Sensing ◽  
Low Concentrations ◽  
Ultrafine Nanofibers ◽  
Different Diameters ◽  
Higher Sensitivity

Polyvinyl alcohol/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PVA/PEDOT:PSS) composite ultrafine fibers were successfully fabricated by high pressure airflow assisted electrospinning. The electrical properties of PVA/PEDOT:PSS nanofibers with different diameters were characterized. The average diameter of the nanofibers can be down to 68 nm. Due to its large specific surface area, ammonia sensing of the ultrafine nanofibers is more sensitive than the traditional electrospun fibers (average fiber diameter of 263 nm). The ammonia sensing properties of the samples were tested by impedance analysis. The results show that ultrafine PVA/PEDOT:PSS nanofibers are more suitable for detecting low concentrations of ammonia with higher sensitivity.

scholarly journals Influence of the Protein Content on Fiber Morphology and Heat Treatment of Electrospun Potato Protein–Maltodextrin Fibers

2021 ◽  
Vol 11 (17) ◽  
pp. 7896
Author(s):  
Monika Gibis ◽  
Franziska Pribek ◽  
Ines Kutzli ◽  
Jochen Weiss
Keyword(s):  
Thermal Treatment ◽  
Protein Content ◽  
Production Rate ◽  
Fiber Diameter ◽  
Average Diameter ◽  
Diameter Distribution ◽  
Fiber Morphology ◽  
Potato Protein ◽  
Ultrafine Fibers ◽  
Needleless Electrospinning

The production of ultrafine fibers of proteins and polysaccharides by needleless electrospinning can be performed prior to a thermal treatment to form glycoconjugates via the first stage of the Maillard reaction. The aim was to produce potato protein–maltodextrin conjugates with a varying protein content of 0.05, 0.1, 0.15, and 0.2 g/mL by needleless electrospinning and subsequent thermal treatment (0, 6, 12, 24, and 48 h at 65 °C and 75% relative humidity). The concentrations of the maltodextrins, with a dextrose equivalent of 2 and 21, were kept constant at 0.8 and 0.1 g/mL. The highest fiber production rate was achieved with a protein content of 0.1 g/mL (5.8 ± 0.4 g/h). With increasing protein content, the production rate decreased to 2.8 ± 0.5 g/h. The fibers obtained from the spinning solution containing 0.2 g/mL protein showed the largest average diameter (4.0 ± 1.5 µm) and the broadest fiber diameter distribution. The protein content of the fibers was close to that of the corresponding spinning solution. The browning index after 48 h of heating increased for all samples (9.7–14.7) compared to the unheated samples (1.1–3.3). The results indicate that the protein content has an impact on the yield, the fiber diameter, and the morphology of the fibers.

scholarly journals Ammonia Sensing Behaviors of TiO2-PANI/PA6 Composite Nanofibers

Sensors ◽  
2012 ◽  
Vol 12 (12) ◽  
pp. 17046-17057 ◽  
Author(s):  
Qingqing Wang ◽  
Xianjun Dong ◽  
Zengyuan Pang ◽  
Yuanzhi Du ◽  
Xin Xia ◽  
...  
Keyword(s):  
Composite Nanofibers ◽  
Ammonia Sensing

scholarly journals Effect of CSA Concentration on the Ammonia Sensing Properties of CSA-Doped PA6/PANI Composite Nanofibers

Sensors ◽  
2014 ◽  
Vol 14 (11) ◽  
pp. 21453-21465 ◽  
Author(s):  
Zengyuan Pang ◽  
Jiapeng Fu ◽  
Pengfei Lv ◽  
Fenglin Huang ◽  
Qufu Wei
Keyword(s):  
Composite Nanofibers ◽  
Sensing Properties ◽  
Ammonia Sensing ◽  
Pani Composite

scholarly journals Morphological and morphometric analysis of skeletal muscle between male and female young adult Colossoma macropomum (Characiformes: Serrasalmidae)

2016 ◽  
Vol 14 (2) ◽  
Author(s):  
Fernanda De Mello ◽  
Daruzi Felippe ◽  
Leandro C. Godoy ◽  
Nívia Lothhammer ◽  
Luis R. J. Guerreiro ◽  
...  
Keyword(s):  
Body Weight ◽  
Fish Species ◽  
White Muscle ◽  
Fiber Diameter ◽  
Muscle Growth ◽  
Weak Correlation ◽  
Morphological Pattern ◽  
Large Size ◽  
Large Fiber ◽  
Different Diameters

ABSTRACT This study aimed to evaluate muscle organization in tambaqui in order to describe the muscle growth process. We analyzed the morphometric pattern of fibers from white muscle of young-adults (300 days) by smaller diameter. The organization of white muscle exhibited a typical morphological pattern found in other fish species. Heavier animals showed higher frequency of larger diameter fibers (>50 μm ) and smaller animals had higher frequency of smaller diameter fibers (<20 μm ) (P =0.005). However, both animals showed the same frequency of intermediate diameter fibers (20-50 μm ). Body weight showed a positive correlation with muscle diameter fiber (r=0.45), being 20-50 μm the diameters that contributed the most to animal weight (P <0.0001). A weak correlation between fiber diameter and animal sex was observed (r=0.2). Females showed higher frequency of large fiber diameters (>50 μm ) than males. However, there was no difference between body weight and sex (P =0.8). Our results suggest that muscle growth is by hypertrophy and hyperplasia due to a mosaic appearance from different diameters fibers, which is characteristic of large size fish species.

Technique to Measure Adhesive Forces Between Electrospun Nanofibers

2009 ◽  
Vol 1240 ◽  
Author(s):  
Qiang Shi ◽  
Kai-Tak Wan ◽  
Shing-Chung Wong ◽  
Pei Chen ◽  
Todd A. Blackledge
Keyword(s):  
Unit Area ◽  
Fiber Diameter ◽  
Electrospun Nanofibers ◽  
Amorphous Region ◽  
Adhesive Force ◽  
Degree Of Crystallinity ◽  
Scanning Calorimetry ◽  
Ultrafine Fibers ◽  
Dry Adhesion ◽  
Adhesive Forces

AbstractDue to the difficulty in handling nanofibers, little is reported and understood on the dry adhesion between electrospun nanofibers. In this study, we develop a technique to measure the dry adhesive forces between electrospun nanofibers. Of critical importance is the ability to mimic naturally occurring dry adhesion such as that between gecko's and spider's foot hairs and untreated surfaces. The adhesion test was performed on two poly(e-caprolactone) electrospun ultrafine fibers using a nanoforce tensile tester. It was found that the adhesive force per unit area increased with decreasing fiber diameter. The degree of crystallinity, order parameters of macromolecules in the amorphous region and crystallite orientation of the spun fibers were determined by the differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD). The high measured adhesion between single PCL fibers in comparison to other reported values was attributed to crystal orientation due to electrospinning and the increase of adhesive force per unit area with decreasing fiber diameter.

scholarly journals SINTESIS DAN KARAKTERISASI NANOFIBER KOMPOSIT Zn-PVDF KOPOLIMER

2014 ◽  
Vol 16 (1) ◽  
pp. 49-52
Author(s):  
Yelfira Sari ◽  
Muhamad Nasir ◽  
Chandra Risdian ◽  
Syukri Syukri
Keyword(s):  
Crystal Structure ◽  
Phase Structure ◽  
Research Study ◽  
Fiber Diameter ◽  
Average Diameter ◽  
Nanofiber Composite ◽  
Β Phase ◽  
Α Phase ◽  
Structure Morphology ◽  
Electrospinning Method

Sintesis nanofiber komposit Zn-PVDF kopolimer dengan metoda elektrospinning telah berhasil dilakukan. Proses pembuatan nanofiber komposit serta  morfologi yang terbentuk dipengaruhi oleh penambahan Zn-asetat dengan perubahan diameter rata-rata serat dari 357,13 nm menjadi 777,24 nm. Analisis FTIR menunjukkan bahwa struktur kristal nanofiber komposit Zn-PVDF kopolimer didominasi oleh strukturβ-phase, dengan bilangan gelombang 1190,08 cm-1 dan 487,99 cm-1 untuk struktur α-phase dan 1404,18 cm-1; 1280,73 cm-1; 1074,35 cm-1; 881,47 cm-1; dan 840,96 cm-1 untuk struktur β-phase.Kata kunci :nanofiber komposit, Zn-PVDF kopolimer komposit, elektrospinning,kristal struktur, morfologi, diameter fiber The fabrication of Zn-PVDF copolymer nanofiber composite has been investigated in this research study by using electrospinning method. Fabrication and morphology of nanofiber composite is influenced by the addition of Zn-acetate. The average diameter of nanofiber composites increase with an addition of Zn-acetate, from 357,13 to 777,24nm. FTIRanalysisshowedthat thecrystalstructure ofPVDFnanofiberis dominatedby β-phase , thewave number 1190,08 cm-1 and 487,99 cm-1 for α-phase structure and 1404,18cm-1; 1280,73cm-1; 1074,35cm-1; 881,47cm-1and840,96cm-1 for β-phase structure respectively.Key words : nanofiber composite, Zn-PVDF copolymer composite, electrospinning, crystal structure,  morphology, fiber diameter

Density Weibull Analysis of Pineapple Leaf Fibers (PALF) with Different Diameters

2016 ◽  
Vol 869 ◽  
pp. 384-390 ◽  
Author(s):  
Gabriel Oliveira Glória ◽  
Giulio Rodrigues Altoé ◽  
Pedro Amoy Netto ◽  
Frederico Muylaert Margem ◽  
Fabio de Oliveira Braga ◽  
...  
Keyword(s):  
Fiber Diameter ◽  
Natural Fibers ◽  
Limited Information ◽  
Weibull Analysis ◽  
Synthetic Fibers ◽  
Statistic Method ◽  
Lignocellulosic Fiber ◽  
Large Dispersion ◽  
Dimensional Uniformity ◽  
Different Diameters

Societal, economical, technical and environmental advantages are today justifying the replacement of synthetic fibers by natural fibers. However, natural fibers obtained from plants do not present the same dimensional uniformity. In fact, they show large dispersion of values, as compared to synthetic fibers. In the case of the lignocellulosic fiber extracted from the pineapple leaf, limited information exists regarding the correlation between its properties and dimensional characteristics. In particular, so far, no investigation has been carried out on the influence of the diameter and the density of pineapple fibers. Therefore, the objective of this work was to measure the density of pineapple fibers and to define, by means of the Weibull statistic method, its dependence on the corresponding fiber diameter.

Preparation of PCL/PVP/Ag Nanofiber Membranes by Electrospinning Method

2012 ◽  
Vol 268-270 ◽  
pp. 580-583 ◽  
Author(s):  
Yong Tang Jia ◽  
Cui Wu ◽  
Feng Chun Dong ◽  
Gang Huang ◽  
Xian Hua Zeng
Keyword(s):  
Silver Nanoparticles ◽  
Photoelectron Spectroscopy ◽  
Composite Nanofibers ◽  
Average Diameter ◽  
Vinyl Pyrrolidone ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrospinning Method ◽  
Nanofiber Membranes ◽  
Poly Vinyl Pyrrolidone

The composite nanofiber membranes of poly (ε-caprolactone)/poly(vinyl pyrrolidone) (PCL/PVP) containing silver nanoparticles were prepared by electrospinning method. The morphology of composite nanofibers was characterized by scanning electron microscopy (SEM). The silver nanoparticles on the electrospun fibers were characterized by X-Ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The contact angle and water uptake of PCL/PVP/Ag nanofiber membranes were measured. The SEM photos indicated that the average diameter of the fibers was significantly decreased with the addition of silver nanoparticles. The X-Ray images showed that Ag nanoparticles were distributed on the surface of nanofiber membranes. When the PVP mole ratio was higher than 15%, the nanofiber membranes showed good hydrophilic property. The PCL/PVP/Ag nanofiber membranes could be applied to prepare wound dressing.

Effect of In2O3 nanofiber structure on the ammonia sensing performances of In2O3/PANI composite nanofibers

2016 ◽  
Vol 52 (2) ◽  
pp. 686-695 ◽  
Author(s):  
Zengyuan Pang ◽  
Qingxin Nie ◽  
Anfang Wei ◽  
Jie Yang ◽  
Fenglin Huang ◽  
...  
Keyword(s):  
Composite Nanofibers ◽  
Ammonia Sensing ◽  
Pani Composite

scholarly journals A Comparative Study of Theoretical Methods to Estimate Semiconductor Nanoparticles’ Size

Crystals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 226 ◽  
Author(s):  
Fernando Rodríguez-Mas ◽  
Juan Carlos Ferrer ◽  
José Luis Alonso ◽  
David Valiente ◽  
Susana Fernández de Ávila
Keyword(s):  
Average Diameter ◽  
Theoretical Models ◽  
Experimental Results ◽  
Bandgap Energy ◽  
Band Model ◽  
Three Solutions ◽  
The Best Approximation ◽  
Transmission Electron ◽  
Different Diameters ◽  
Brus Equation

In this paper, we compare four different methods to estimate nanoparticle diameters from optical absorption measurements, using transmission electron microscopy (TEM) images as a reference for the nanoparticle size. Three solutions of colloidal nanoparticles coated with thiophenol with different diameters were synthesized by thiolate decomposition. The nanoparticle sizes were controlled by the addition of a certain volume of a 1% sulphur solution in toluene. TEM measurements showed that the average diameter for each type of these nanoparticles was 2.8 nm, 3.2 nm, and 4.0 nm. The methods studied for the calculation of the nanoparticles diameter were: The Brus model, the hyperbolic band model (HBM), the Henglein model, and the Yu equation. We evaluated the importance of a good knowledge of the nanoparticle bandgap energy, and the nature of electronic transitions in the semiconductor. We studied the effects that small variations in the electron and hole effective mass values produced in the Brus equation and in the HBM model for CdS, PbS, and ZnS nanoparticles. Finally, a comparison was performed between the data provided by these models and the experimental results obtained with TEM images. In conclusion, we observed that the best approximation to the experimental results with TEM images was the Brus equation. However, when the bandgap energy was close to the bulk bandgap energy, the theoretical models did not adjust correctly to the size measured from the TEM images.

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