Development of a novel preparation method for conductive PES ultrafine fibers with self-formed thin PES/CNTs composite layer by vapor treatment

RSC Advances ◽  
2015 ◽  
Vol 5 (53) ◽  
pp. 42305-42310 ◽  
Author(s):  
Zhimei Wei ◽  
Minle Peng ◽  
Fang Qiu ◽  
Xiaojun Wang ◽  
Shengru long Shengru long ◽  
...  

Conductive electrospun fibers have attracted widespread interest in the field of electromagnetics.

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Shuqi Zhu ◽  
Hao Yu ◽  
Yanmo Chen ◽  
Meifang Zhu

Dry-jet-wet-electrospinning (DJWE) was carried out to study the formational mechanism of poly(hydroxybutyrate-co-hydroxyvalerate) electrospun fibers. Morphological comparison between normal electrospinning (NE) and DJWE was investigated. The results showed that jet could solidify quickly in DJWE to avoid bead collapse or fiber coherence. Jet structures could be maintained at very low collection distance. Beanpod-like beads, which were named as primary beads, could be seen at the boundary of stability and instability section and divided into spindle-like beads with longer collection distance. Bead-free electrospun fibers from DJWE had few bonding points among each other, and fast solidification and double-diffusion led to rough and shriveled fiber surface. DJWE mats were higher hydrophobic than that from NE due to more loose structure and higher surface porosity. Higher bead ratio on the surface and rounder bead structure resulted in higher hydrophobicity.


2008 ◽  
Vol 1134 ◽  
Author(s):  
Chitrabala Subramanian ◽  
Samuel C. Ugbolue ◽  
Steven B. Warner ◽  
Prabir K. Patra

AbstractElectrospinning is a technique of producing nanofibers from polymer solution/melt solely under the influence of electrostatic forces. In this research, we investigated the formation of nanofibers by melt electrospinning polycaprolactone (PCL). The effect of process parameters such as molecular weight, applied voltage, and electrode separation on the fiber diameter was investigated. Controlling the process parameters could help increase the proportion of ultrafine fibers in the melt electrospun nonwoven mat. The velocity of the straight jets was in the range of 0.2-1 m/s. The melt electrospun fibers were characterized with respect to fiber diameter, distribution, mechanical properties and birefringence. Melt electrospun polycaprolactone fibers had a diameter distribution of the order of 5 -20 μm. The birefringence of the melt electrospun fibers increased with decrease in fiber diameter.


2014 ◽  
Vol 1065-1069 ◽  
pp. 3136-3139
Author(s):  
Chun Xue Zhang ◽  
Bo Sun

Polyacrylonitrile (PAN) ultrafine fiber was prepared by electrospinning of PAN solution made from waste PAN. Diameters of the electrospun fibers as well as distribution of them were characterized by scanning electron microscope. The results show that the waste polyacrylonitrile/ N,N-dimethylformamide solution can be used for electrospinning after simply treatment-filtration. Uniform ultrafine fibers with diameters between 100 nm and 250nm could be obtained. With increasing concentration of waste PAN from 9% to 10%, the morphology was changed from beaded fiber to uniform fiber structure and the fiber diameter was also increased from110nm to 184 nm gradually. A narrow distribution of fiber diameters was observed at a voltage of 22kV. However, more beaded fibers were observed for longer tip–collecting foil distance.


Author(s):  
R. W. Anderson ◽  
D. L. Senecal

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.


Author(s):  
Toshihiko Takita ◽  
Tomonori Naguro ◽  
Toshio Kameie ◽  
Akihiro Iino ◽  
Kichizo Yamamoto

Recently with the increase in advanced age population, the osteoporosis becomes the object of public attention in the field of orthopedics. The surface topography of the bone by scanning electron microscopy (SEM) is one of the most useful means to study the bone metabolism, that is considered to make clear the mechanism of the osteoporosis. Until today many specimen preparation methods for SEM have been reported. They are roughly classified into two; the anorganic preparation and the simple preparation. The former is suitable for observing mineralization, but has the demerit that the real surface of the bone can not be observed and, moreover, the samples prepared by this method are extremely fragile especially in the case of osteoporosis. On the other hand, the latter has the merit that the real information of the bone surface can be obtained, though it is difficult to recognize the functional situation of the bone.


Author(s):  
Diane M. Vanderwalker

There is a widespread interest in understanding the properties of Al-base alloys so that progress can be made toward extending their present applications in the aircraft industry. Al-Zn-Mg is precipitation hardened to gain its high strength; however, during aging the formation of heterogeneous precipitates on the grain boundaries creates a precipitate-free zone in the adjacent region. Since high angle grain boundaries are not easily characterized, it is difficult to establish a relationship between the precipitate and the boundary structure. Therefore, this study involves precipitation on low angle grain boundaries where the boundary and the precipitate can be fully analyzed.


2019 ◽  
Author(s):  
Xiaohan Wu ◽  
Juliette Billaud ◽  
Iwan Jerjen ◽  
Federica Marone ◽  
Yuya Ishihara ◽  
...  

<div> <div> <div> <p>All-solid-state batteries are considered as attractive options for next-generation energy storage owing to the favourable properties (unit transference number and thermal stabilities) of solid electrolytes. However, there are also serious concerns about mechanical deformation of solid electrolytes leading to the degradation of the battery performance. Therefore, understanding the mechanism underlying the electro-mechanical properties in SSBs are essentially important. Here, we show three-dimensional and time-resolved measurements of an all-solid-state cell using synchrotron radiation x-ray tomographic microscopy. We could clearly observe the gradient of the electrochemical reaction and the morphological evolution in the composite layer. Volume expansion/compression of the active material (Sn) was strongly oriented along the thickness of the electrode. While this results in significant deformation (cracking) in the solid electrolyte region, we also find organized cracking patterns depending on the particle size and their arrangements. This study based on operando visualization therefore opens the door towards rational design of particles and electrode morphology for all-solid-state batteries. </p> </div> </div> </div>


Author(s):  
Jian-Shing Luo ◽  
Hsiu Ting Lee

Abstract Several methods are used to invert samples 180 deg in a dual beam focused ion beam (FIB) system for backside milling by a specific in-situ lift out system or stages. However, most of those methods occupied too much time on FIB systems or requires a specific in-situ lift out system. This paper provides a novel transmission electron microscopy (TEM) sample preparation method to eliminate the curtain effect completely by a combination of backside milling and sample dicing with low cost and less FIB time. The procedures of the TEM pre-thinned sample preparation method using a combination of sample dicing and backside milling are described step by step. From the analysis results, the method has applied successfully to eliminate the curtain effect of dual beam FIB TEM samples for both random and site specific addresses.


Author(s):  
Chuan Zhang ◽  
Jane Y. Li ◽  
John Aguada ◽  
Howard Marks

Abstract This paper introduces a novel sample preparation method using plasma focused ion-beam (pFIB) milling at low grazing angle. Efficient and high precision preparation of site-specific cross-sectional samples with minimal alternation of device parameters can be achieved with this method. It offers the capability of acquiring a range of electrical characteristic signals from specific sites on the cross-section of devices, including imaging of junctions, Fins in the FinFETs and electrical probing of interconnect metal traces.


Sign in / Sign up

Export Citation Format

Share Document