scholarly journals Fabrication of Electrospun Polymer Nanofibers with Diverse Morphologies

Molecules ◽  
2019 ◽  
Vol 24 (5) ◽  
pp. 834 ◽  
Author(s):  
Chenyu Wang ◽  
Jun Wang ◽  
Liangdan Zeng ◽  
Ziwen Qiao ◽  
Xiaochen Liu ◽  
...  
Keyword(s):  
High Porosity ◽  
Polymer Nanofibers ◽  
Shell Side ◽  
Healthcare Applications ◽  
Simple Process ◽  
Surface Areas ◽  
Hollow Interior ◽  
Polymer Nanofiber ◽  
Potential Applications ◽  
Specific Surface Areas

Fiber structures with nanoscale diameters offer many fascinating features, such as excellent mechanical properties and high specific surface areas, making them attractive for many applications. Among a variety of technologies for preparing nanofibers, electrospinning is rapidly evolving into a simple process, which is capable of forming diverse morphologies due to its flexibility, functionality, and simplicity. In such review, more emphasis is put on the construction of polymer nanofiber structures and their potential applications. Other issues of electrospinning device, mechanism, and prospects, are also discussed. Specifically, by carefully regulating the operating condition, modifying needle device, optimizing properties of the polymer solutions, some unique structures of core–shell, side-by-side, multilayer, hollow interior, and high porosity can be obtained. Taken together, these well-organized polymer nanofibers can be of great interest in biomedicine, nutrition, bioengineering, pharmaceutics, and healthcare applications.

Synthesis and Characterization of Mesoporous and Microporous Carbons With Potential Applications as Hydrogen Storage Media

2006 ◽  
Author(s):  
Marco Armandi ◽  
Barbara Bonelli ◽  
Edoardo Garrone
Keyword(s):  
Hydrogen Storage ◽  
Chemical Characterization ◽  
Specific Weight ◽  
High Porosity ◽  
Carbon Phase ◽  
Microporous Carbons ◽  
Surface Areas ◽  
Physico Chemical ◽  
Potential Applications

The preparation and physico-chemical characterization of mesoporous and microporous carbons, obtained via a casting procedure, from a SBA-15 silica and a commercial Na-Y zeolite, is reported. XRD spectra showed that ordered carbon replicas occur in all cases. Micro-Raman spectra showed that rather homogeneous powders are obtained, exhibiting the presence of a graphitized carbon phase of small imperfect graphene sheets, typical of sp2 C, along with an amorphous one, notwithstanding the relatively low temperature adopted during the carbonization processes (1173 K). N2 adsorption isotherms at 77 K allowed the determination of BET surface areas and pore volumes: on account of the high porosity and the low specific weight, with respect to zeolites, for example, these carbon materials could be promising media for hydrogen storage. They could be used as such, or after convenient functionalization or metal doping.

scholarly journals Three-dimensional graphene networks: synthesis, properties and applications

2014 ◽  
Vol 2 (1) ◽  
pp. 40-53 ◽  
Author(s):  
Yanfeng Ma ◽  
Yongsheng Chen
Keyword(s):  
Graphene Oxide ◽  
Three Dimensional ◽  
Porous Structures ◽  
Intrinsic Properties ◽  
Surface Areas ◽  
Synthesis Properties ◽  
Potential Applications ◽  
Specific Surface Areas ◽  
Graphene Foams ◽  
Mechanical Strengths

Abstract Recently, three-dimensional graphene/graphene oxide (GO) networks (3DGNs) in the form of foams, sponges and aerogels have attracted much attention. 3D structures provide graphene materials with high specific surface areas, large pore volumes, strong mechanical strengths and fast mass and electron transport, owing to the combination of the 3D porous structures and the excellent intrinsic properties of graphene. This review focuses on the latest advances in the preparation, properties and potential applications of 3D micro-/nano-architectures made of graphene/GO-based networks, with emphasis on graphene foams and sponges.

ELECTROSPINNING OF BIOMATERIALS AND THEIR APPLICATIONS IN TISSUE ENGINEERING

Nano LIFE ◽  
2012 ◽  
Vol 02 (04) ◽  
pp. 1230010 ◽  
Author(s):  
JEN-CHIEH WU ◽  
H. PETER LORENZ
Keyword(s):  
Tissue Engineering ◽  
Electrospinning Process ◽  
Polymer Fibers ◽  
Nanometer Scale ◽  
High Porosity ◽  
Electrospinning Technique ◽  
Engineering Research ◽  
Fibrous Scaffolds ◽  
Surface Areas ◽  
Tissue Engineering Research

Electrospinning is a process for generating micrometer or nanometer scale polymer fibers with large surface areas and high porosity. For tissue engineering research, the electrospinning technique provides a quick way to fabricate fibrous scaffolds with dimensions comparable to the extracellular matrix (ECM). A variety of materials can be used in the electrospinning process, including natural biomaterials as well as synthetic polymers. The natural biomaterials have advantages such as excellent biocompatibility and biodegradability, which can be more suitable for making biomimic scaffolds. In the last two decades, there have been growing numbers of studies of biomaterial fibrous scaffolds using the electrospinning process. In this review, we will discuss biomaterials in the electrospinning process and their applications in tissue engineering.

scholarly journals Ultrafine porous boron nitride nanofibers synthesized via a freeze-drying and pyrolysis process and their adsorption properties

RSC Advances ◽  
2016 ◽  
Vol 6 (2) ◽  
pp. 1253-1259 ◽  
Author(s):  
Jing Lin ◽  
Lulu Xu ◽  
Yang Huang ◽  
Jie Li ◽  
Weijia Wang ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Specific Surface ◽  
Freeze Drying ◽  
Adsorption Properties ◽  
Pyrolysis Process ◽  
Surface Areas ◽  
Aspect Ratios ◽  
Large Pore ◽  
Specific Surface Areas

Ultrafine porous boron nitride nanofibers with high aspect ratios, high specific surface areas and large pore volumes has been synthesized in large quantity via a freeze-drying and post pyrolysis process.

scholarly journals Experimental Investigation of Coal Dust Wettability Based on Surface Contact Angle

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Gang Zhou ◽  
Han Qiu ◽  
Qi Zhang ◽  
Mao Xu ◽  
Jiayuan Wang ◽  
...  
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Specific Surface ◽  
Coal Dust ◽  
Single Point ◽  
Contact Angles ◽  
Critical Surface ◽  
Volume Percentage ◽  
Surface Areas ◽  
Specific Surface Areas

Wettability is one of the key chemical properties of coal dust, which is very important to dedusting. In this paper, the theory of liquid wetting solid was presented firstly; then, taking the gas coal of Xinglongzhuang coal mine in China as an example, by determination of critical surface tension of coal piece, it can be concluded that only when the surface tension of surfactant solution is less than 45 mN/m can the coal sample be fully wetted. Due to the effect of particle dispersity, compared with the contact angle of milled coal particle, not all the contact angles of screened coal powder with different sizes have a tendency to increase. Furthermore, by the experiments of coal samples’ specific surface areas and porosities, it can be achieved that the volume of single-point total pore decreases with the gradual decreasing of coal’s porosity, while the ultramicropores’ dispersities and multipoint BET specific surface areas increase. Besides, by a series of contact angle experiments with different surfactants, it can be found that with the increasing of porosity and the decreasing of volume percentage of ultramicropore, the contact angle tends to reduce gradually and the coal dust is much easier to get wetted.

Facile Method To Synthesize Mesoporous Multimetal Oxides (ATiO3, A = Sr, Ba) with Large Specific Surface Areas and Crystalline Pore walls

2010 ◽  
Vol 22 (4) ◽  
pp. 1276-1278 ◽  
Author(s):  
Xiaoxing Fan ◽  
Ying Wang ◽  
Xinyi Chen ◽  
Ling Gao ◽  
Wenjun Luo ◽  
...  
Keyword(s):  
Specific Surface ◽  
Surface Areas ◽  
Specific Surface Areas

Organic-free large-pore-sized γ-alumina for the removal of three azo dyes from aqueous solution

2021 ◽  
Vol 11 (9) ◽  
pp. 1534-1545
Author(s):  
Xuhui Wang ◽  
Jianchuan Sun ◽  
Shuaiqi Chen ◽  
Shuai Ren ◽  
Awang Gao ◽  
...  
Keyword(s):  
Dye Adsorption ◽  
Specific Area ◽  
Kinetics Study ◽  
Order Model ◽  
Surface Areas ◽  
Adsorption Capacities ◽  
Direct Blue ◽  
Calculation Results ◽  
Specific Surface Areas ◽  
Adsorption Rates

A series of γ-alumina with different pore sizes (5.7 nm–21.6 nm) and similar specific surface areas were synthesized via an organic-free method and their adsorption rates and capacities for Congo red (CR), direct blue 78 (DB78) and direct green 26 (DG26) were investigated. The kinetics study reveals that the dye adsorptions of all γ-alumina samples fit the pseudo-2nd-order model. For CR, its k2 and the pore size of absorbent are in a linear relationship at low dye concentrations. Both of the experimental results and Langmuir isotherm calculation results suggest that the dye adsorption capacities of the γ-alumina prepared in our lab are much higher than those of other γ-alumina reported in literatures. GA-1 with the largest specific area of surface and largest size of pores exhibits a CR adsorption capacity up to 4213.6 mg/g. In addition, initial dye adsorption rates of the γ-alumina prepared in-house are much higher than that of the γ-alumina prepared with the commercially available alumina under the same conditions.

Carbon Microspheres Prepared by High Internal Phase Emulsion Polymerization

2011 ◽  
Vol 239-242 ◽  
pp. 3105-3108
Author(s):  
Ming Xian Liu ◽  
Li Hua Gan ◽  
Jun Hu ◽  
Hong Lai Liu ◽  
Long Wu Chen
Keyword(s):  
Electron Microscopy ◽  
Specific Surface ◽  
Aqueous Phase ◽  
Apparent Density ◽  
Tween 80 ◽  
Carbon Microspheres ◽  
High Internal Phase Emulsion ◽  
Surface Areas ◽  
Internal Phase ◽  
Specific Surface Areas

In this paper, we present a novel approach for the synthesis of carbon microspheres via the polymerization of a high internal phase emulsion (HIPE). By using Span 80 and Tween 80 as emulsifiers, 1iquid paraffin as oil phase, and the mixture of resorcinol/formaldehyde (R/F) solution as aqueous phase, an O/W emulsion was obtained. This emulsion phase inverted to a W/O HIPE induced by ammonia which served as the polymerization catalyst. Carbon microspheres (CMs) were prepared by polymerization of the HIPE, followed by drying and carbonization. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) analyzer were used to characterize as-prepared CMs. The results indicate that, in case of 0.25 wt% ammonia of the HIPE, the diameters of CMs decreased from about 2 to 1 μm when the mass fraction of aqueous R/F decreased from 0.714 to 0.357; the apparent density and the specific surface areas of the CMs, however, did not change obviously, which are about 0.6 g/cm3and 200 m2/g, respectively. The dosage of ammonia has a significant influence on the morphology and properties of CMs. With increasing of the ammonia mass to 1 wt% of the HIPE, the resultant carbon materials comprise not only CMs, but also some carbon sheets; the apparent density of which increased to 0.9 g/cm3and the specific surface areas of which decreased to below 100 m2/g. In addition, the other parameters for CMs preparation were also investigated. It was found that the proper conditions were controlling the temperature of 303-333 K and the oil/aqueous phase mass ratio of 2.5:7.

The Experimental Study on Grinding Properties of Gas Quenching Steel Slag

2011 ◽  
Vol 189-193 ◽  
pp. 612-617
Author(s):  
Hong Wei Xing ◽  
Yue Long ◽  
Xiu Li ◽  
Gao Liang Li ◽  
Yu Zhu Zhang ◽  
...  
Keyword(s):  
Specific Surface ◽  
New Technology ◽  
Steel Slag ◽  
Economic Benefits ◽  
Surface Areas ◽  
Mineral Phases ◽  
Quenching Process ◽  
Gas Quenching ◽  
Specific Surface Areas ◽  
Better Than

A gas quenching process to deal with steel slag and its characteristics of the new technology was briefly introduced. The grinding characteristics, mineral phases of gas quenching steel slag and the potential economic benefits of using it as cement mixing material was studied by compared to heat-stew steel slag. The results indicated that the specific surface areas (S) and grinding times (t) of the gas quenching steel slag showed a first order exponential decay relationship. With the extension of time, the specific surface areas of heat-stew steel slag was tending to balance earlier than that of gas quenching steel slag; The energy consumption of gas quenching steel slag was much lower than that of heat-stew steel slag. Gas quenching steel slag was comprised of C2S, C3S, a certain amount of (Ca2(Al, Fe)2O5）and RO phase, but the content of RO phase was relatively low, which increased the grindability of the quenching steel slag, so that the grindability of gas quenching steel slag was much better than that of heat-stew steel slag. Gas quenching steel slag prepared for cement addictives would bring great economic benefits.

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