One-pot green extraction of high charge density cellulose nanocrystals with high yield for bionanocomposites

TEMPO-mediated oxidation of microgranular cellulose results in particles of three different length scales: cellulose nanocrystals as well as small (μm) and larger (tens of μm) porous particles with high charge density.

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Study on the High Charge Density Polyamine System in Controlling Dissolved and Colloidal Substances of High-Yield Pulp

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.1363 ◽

2011 ◽

Vol 236-238 ◽

pp. 1363-1366

Author(s):

Qi Jie Chen ◽

Ping Wang ◽

Yong Xiang Yan

Keyword(s):

Charge Density ◽

Triple System ◽

Kraft Pulp ◽

High Yield ◽

Cationic Starch ◽

High Charge ◽

Bleached Kraft Pulp ◽

High Charge Density ◽

Microscope Photograph ◽

Dissolved And Colloidal Substances

In recent years High yield pulp (HYP) is being used at an increasing rate to replace bleached hardwood kraft pulp in the manufacturing of high quality paper products. However, HYP has more dissolved and colloidal substances (DCS), when compared with fully bleached kraft pulp. In general these DCS have an anionic character, and they often disturb the papermaking process. In the paper, the effects of high charge density polyamine (PA) single, dual and triple system on DCS control in high yield pulp were studied. The results showed that the DCS control effects of the PA/HCS (high cationic starch)/CPAM (cationic polyacrylamide) triple system were better than the PA/HCS dual system and the PA single system. In the PA/HCS/CPAM triple system, when the dosage of the PA was 0.06% and the dosage was 0.1% and 0.05% for HCS and CPAM, respectively, the zeta potential of pulp increased by a certain degree, drainage property of pulp improved remarkably, the turbidity of the DCS water was near to zero, and the cationic demand of DCS water decreased by 70.8%. The microscope photograph of fibers also confirmed that the polymers in the PA/HCS/CPAM triple system had very good synergetic effects on the removal of DCS in high yield pulp.

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Sedimentation Equilibrium of High Charge Density Cationic Polyelectrolytes

Water-Soluble Polymers ◽

10.1007/978-1-4613-4583-1_21 ◽

1973 ◽

pp. 327-347

Author(s):

Maurice Schmir ◽

Alan Rembaum

Keyword(s):

Charge Density ◽

Sedimentation Equilibrium ◽

High Charge ◽

High Charge Density ◽

Cationic Polyelectrolytes

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Correlation of Impedance and Effective Electrode Area of Iridium Oxide Neural Electrodes

Australian Journal of Chemistry ◽

10.1071/ch17218 ◽

2017 ◽

Vol 70 (9) ◽

pp. 1016 ◽

Cited By ~ 2

Author(s):

Alexander R. Harris ◽

Antonio G. Paolini

Keyword(s):

Charge Density ◽

Iridium Oxide ◽

Neural Stimulation ◽

Electrode Impedance ◽

Platinum Electrodes ◽

High Charge ◽

State Diffusion ◽

High Charge Density ◽

Steady State Diffusion ◽

Total Activation

Iridium oxide is routinely used for bionic applications owing to its high charge injection capacity. The electrode impedance at 1 kHz is typically reported to predict neural recording performance. In this article, the impedance of activated iridium oxide films (AIROFs) has been examined. The impedance of unactivated iridium electrodes was half that of platinum electrodes of similar geometry, indicating some iridium oxide was present on the electrode surface. A two time constant equivalent circuit was used to model the impedance of activated iridium. The impedance at low and intermediate frequencies decreased with increasing number of activation pulses and total activation charge. The impedance at 12 Hz correlated with the steady-state diffusion electroactive area. The impedance at 12 Hz also correlated with the charge density of the electrode. The high charge density and low impedance of AIROFs may provide improved neural stimulation and recording properties compared with typically used platinum electrodes.

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