Fabrication of Shape-Controllable Polyaniline Micro/Nanostructures on Organic Polymer Surfaces:  Obtaining Spherical Particles, Wires, and Ribbons

2007 ◽  
Vol 111 (15) ◽  
pp. 3918-3926 ◽  
Author(s):  
Wenbin Zhong ◽  
Yongxin Wang ◽  
Yan ◽  
Yufeng Sun ◽  
Jianping Deng ◽  
...  
1993 ◽  
Vol 40 (1) ◽  
pp. 73-81 ◽  
Author(s):  
G.A. Takacs ◽  
V. Vukanovic ◽  
D. Tracy ◽  
J.X. Chen ◽  
F.D. Egitto ◽  
...  

2007 ◽  
Vol 55 (1-2) ◽  
pp. 59-67 ◽  
Author(s):  
X.C. Wang ◽  
H.L. Yuan ◽  
Y.J. Liu ◽  
P.K. Jin

A pilot-scale fluidised pellet bed (FPB) bioreactor, which combines chemical coagulation, biological degradation, particle pelletisation and separation in one unit, was applied for onsite wastewater treatment and reuse. As a result of rational use of inorganic coagulant and organic polymer and moderate mechanical agitation, spherical particles were generated in the upflow column and a well-fluidised bed was formed. With a continuous supply of dissolved oxygen through a recycling loop, an aerobic condition was kept in the bottom section of the FPB column. Under such conditions the pellets in the FPB column showed the following characteristics: (1) compact structure and high density; (2) rich in microorganisms; and (3) high MLSS and MLVSS concentrations. Therefore, the FPB bioreactor achieved more than 90% removal of SS, COD, BOD and TP from raw domestic wastewater within a total hydraulic retention time (HRT) of only about 30 minutes. It also showed nitrification and denitrification ability and the TN removal could be about 50% as the recycling ratio was increased to 1:1. The treated water quality is generally competitive with the secondary effluent from a conventional activated sludge process. With these advantages the FPB bioreactor is recommendable as a compact system for onsite wastewater treatment and reuse.


2015 ◽  
Vol 638 ◽  
pp. 20-26
Author(s):  
Sergiu Cecoltan ◽  
Daniela G. Petre ◽  
Eliza Georgeta Stan ◽  
Eugeniu Vasile ◽  
Horia Emil Cioflan ◽  
...  

This work describes the synthesis of composite particles for bone regeneration. The developed method is based on a bio-inspired approach starting from the composition, properties and hierarchical organization of bone extracellular matrix (ECM). The composite material was designed as spherical particles able to ensure interconnected porosity through their assembling inside the bone defect. nanohydroxyapatite was generated in the organic matrix in order to mimic the composition and the organization of the mineral phase in bone tissue. A collagen derivative was used as main natural polymer of the organic matrix of the composite material, in order to mimic the composition of bone ECM. Alginate represents the second organic polymer due to its recognized capacity to easily generate spherical particles in divalent cations solutions. The combination of this polysaccharide with the two previously mentioned components simultaneously responds the architectural and compositional constraints of this approach. The particles were obtained using a modular electrostatic bead generator developed in our laboratory. Briefly, a solution containing the biopolymers was extruded into a mineralisation solution. Spherical particles with diameters of about 500 μm were obtained. They were characterised by scanning electron microscopy, X-ray diffraction, stability in aqueous media. The obtained results confirmed the importance of alginate to generate spherical particles and the potential of such materials to successfully serve the targeted application.


1986 ◽  
Vol 60 (9) ◽  
pp. 3315-3322 ◽  
Author(s):  
E. Sutcliffe ◽  
R. Srinivasan

1997 ◽  
Vol 358 (1-2) ◽  
pp. 244-247 ◽  
Author(s):  
S. Schneider ◽  
F. Simon ◽  
D. Pleul ◽  
H.-J. Jacobasch

2012 ◽  
Vol 529-530 ◽  
pp. 436-440 ◽  
Author(s):  
S.B. Cho ◽  
E.M. An ◽  
Sujeong Lee ◽  
H.D. Jang ◽  
Ill Yong Kim ◽  
...  

Osteoconductive bone-repairing materials with mechanical properties analogous to those of human bone can be prepared through the combination of an osteoconductive ceramic filler with an organic polymer. Osteoconduction is archived from apatite formation on substrates. Previously, we reported that novel osteoconductive spherical particles in a binary CaO-SiO2 system were produced through a sol-gel process as ceramic filler for the fabrication of composites. In this study, we fabricated the composites consisting of polyetheretherketone (PEEK) and 30CaO·70SiO2 (CS) spherical particles and evaluated the effects of heat treatment in the range of 320-360 °C on apatite formation of the composites in a simulated body fluid. The prepared composites of PEEK and CS particles form hydroxyapatite on their surfaces in the simulated body fluid. The induction periods of hydroxyapatite on the composites decreased with increasing the amount of CS particles and decreasing the temperature for heat treatment. The apatite formation was affected by exposure of ceramic filler on the polymer matrix.


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