scholarly journals Role of highly branched, high molecular weight polymer structures in directing uniform polymer particle formation during nanoprecipitation

2016 ◽  
Vol 52 (20) ◽  
pp. 3915-3918 ◽  
Author(s):  
Fiona L. Hatton ◽  
Pierre Chambon ◽  
Alison C. Savage ◽  
Steve P. Rannard
Keyword(s):  
Molecular Weight ◽  
Growth Mechanism ◽  
Nucleation And Growth ◽  
Polymer Particle ◽  
Branched Polymers ◽  
High Molecular Weight Polymer ◽  
Molecular Weight Polymer ◽  
Mixing Techniques ◽  
Nucleation And Growth Mechanism

The presence of highly branched polymers with >100 conjoined primary chains is shown to induce a novel rapid nucleation and growth mechanism within polymer nanoprecipitation yielding functional, uniform nanoparticles without stabilisers, filtration or rapid mixing techniques.

The role of blending in polymer conditioning of waste activated sludge

2001 ◽  
Vol 44 (6) ◽  
pp. 63-66 ◽  
Author(s):  
A. Erdinçler; ◽  
S. Koseoǧly ◽  
T. Onay
Keyword(s):  
Molecular Weight ◽  
Activated Sludge ◽  
Waste Activated Sludge ◽  
Capillary Suction ◽  
High Molecular Weight Polymer ◽  
Molecular Weight Polymer ◽  
Biological Polymers ◽  
Time Periods ◽  
Control Samples

This paper presents the results of an investigation on the role of blending in sludge polymer conditioning by evaluating the polymer consumption, and measuring the capillary suction time of waste activated sludge samples blended for different time periods. All of the sludge samples, including non-blended control samples, were conditioned by a cationic high molecular weight polymer in desired concentrations. The protein concentrations of the sludge samples increased as a biological confirmation of cell disruption or desorption of some part of biological polymers present in sludge. Blending decreased the critical polymer dosages required to condition the waste activated sludge samples depending on the blending time applied to the samples.

Formation of coherent twins in YBa2Cu3O7–δ superconductors

1989 ◽  
Vol 4 (4) ◽  
pp. 795-801 ◽  
Author(s):  
C. J. Jou ◽  
J. Washburn
Keyword(s):  
Oxygen Uptake ◽  
Growth Mechanism ◽  
Oxygen Uptake Rate ◽  
Nucleation And Growth ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Twin Formation ◽  
Boundary Model ◽  
Nucleation And Growth Mechanism

A nucleation-and-growth mechanism for the twin formation in YBa2Cu3O7–δ superconductors based on the oxygen uptake rate curve and published transmission electron microscopic observations is proposed together with an oxygen-depleted twin boundary model. The difficulty of reaching stoichiometric YBa2Cu3O7 is explained.

Intrinsic viscoelasticity in thin high-molecular-weight polymer films

2014 ◽  
Vol 89 (6) ◽  
Author(s):  
Xiaoyuan Sheng ◽  
Frédéric Wintzenrieth ◽  
Katherine R. Thomas ◽  
Ullrich Steiner
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Polymer Films ◽  
High Molecular Weight Polymer ◽  
Molecular Weight Polymer

scholarly journals Nucleation/Growth and Optical Proprieties of Co-doped ZnO Electrodeposited on ITO Substrate

2021 ◽  
Vol 12 (5) ◽  
pp. 6776-6787
Keyword(s):  
Cyclic Voltammetry ◽  
Growth Mechanism ◽  
Supporting Electrolyte ◽  
Saturated Calomel Electrode ◽  
Nucleation And Growth ◽  
Visible Range ◽  
Zno Films ◽  
Doped Zno ◽  
Nucleation And Growth Mechanism ◽  
Co Doped

A Co-doped ZnO layer was prepared by electrodeposition method on indium doped tin oxide (ITO) substrate using a cathodic reduction from nitrate medium with different doping percentages of cobalt. The bath temperature was controlled at 70 °C. The films were cathodically electrodeposited in a bath containing 5 mM Zn(NO3)2. 6H2O, while the source of Co is Co(NO3)2.6H2O where 0.1M KNO3 was used as supporting electrolyte. The nucleation and growth mechanism of Co-doped ZnO nuclei have been studied by cyclic voltammetry and chronoamperometry. The cyclic voltammetry shows that the electrodeposition of ZnO and Co-doped ZnO at a negative potential around -1.0 V versus saturated calomel electrode (SCE) is a quasi-reversible reaction controlled by the diffusion process. Comparing current transients curves obtained by the chronoamperometric method with the theoretical curves of current density j versus t ½ allows us to say that the nucleation is 3D instantaneous, as shown in SEM analysis. The presence of Co does not modify the nucleation and growth mechanism. The XRD patterns show that the substitution of zinc by cobalt does not change the würtzite crystal structure, but the crystallite size decreases with the cobalt percentage. The transmittance spectra indicate that the Co-doped ZnO films are transparent in the visible range. The optical gap increases with the doping percentage of cobalt.

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