scholarly journals 3D solid supported inter-polyelectrolyte complexes obtained by the alternate deposition of poly(diallyldimethylammonium chloride) and poly(sodium 4-styrenesulfonate)

2016 ◽  
Vol 7 ◽  
pp. 197-208 ◽  
Author(s):  
Eduardo Guzmán ◽  
Armando Maestro ◽  
Sara Llamas ◽  
Jesús Álvarez-Rodríguez ◽  
Francisco Ortega ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Three Dimensional ◽  
Layer By Layer ◽  
Polymer Conformation ◽  
Polyelectrolyte Complexes ◽  
Diallyldimethylammonium Chloride ◽  
Internal Morphology ◽  
Layer Method ◽  
Adsorbed Mass ◽  
3D Solid

This work addresses the formation and the internal morphology of polyelectrolyte layers obtained by the layer-by-layer method. A multimodal characterization showed the absence of stratification of the films formed by the alternate deposition of poly(diallyldimethylammonium chloride) and poly(sodium 4-styrenesulfonate). Indeed the final organization might be regarded as three-dimensional solid-supported inter-polyelectrolyte films. The growth mechanism of the multilayers, followed using a quartz crystal microbalance, evidences two different growth trends, which show a dependency on the ionic strength due to its influence onto the polymer conformation. The hydration state does not modify the multilayer growth, but it contributes to the total adsorbed mass of the film. The water associated with the polyelectrolyte films leads to their swelling and plastification. The use of X-ray photoelectron spectroscopy has allowed for deeper insights on the internal structure and composition of the polyelectrolyte multilayers.

Heteroepitaxial Nucleation and Growth of Ge ON Si(100) Surfaces Using Remote Plasma Enhanced Chemical Vapor Deposition

1988 ◽  
Vol 116 ◽  
Author(s):  
R.A. Rudder ◽  
S.V. Hattangady ◽  
D.J. Vitkavage ◽  
R.J. Markunas
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Three Dimensional ◽  
Chemical Vapor ◽  
Layer By Layer ◽  
Heteroepitaxial Growth ◽  
Remote Plasma ◽  
Dimensional Growth ◽  
Diffraction Patterns

Heteroepitaxial growth of Ge on Si(100) has been accomplished using remote plasma enhanced chemical vapor deposition at 300*#x00B0;C. Reconstructed surfaces with diffraction patterns showing non-uniform intensity variations along the lengths of the integral order streaks are observed during the first 100 Å of deposit. This observation of an atomically rough surface during the initial stages of growth is an indication of three-dimensional growth. As the epitaxial growth proceeds, the diffraction patterns become uniform with extensive streaking on both the integral and fractional order streaks. Subsequent growth, therefore, takes place in a layer-by-layer, two-dimensional mode. X-ray photoelectron spectroscopy of the early nucleation stages, less than 80 Å, show that there is uniform coverage with no evidence of island formation.

Self-Assembly of Large Scale CdS/TiO2 Film Photocatalyst

2012 ◽  
Vol 512-515 ◽  
pp. 1692-1698 ◽  
Author(s):  
Chun Xiang Li ◽  
Zhao Hua Jiang ◽  
Zhong Ping Yao
Keyword(s):  
Photoelectron Spectroscopy ◽  
Self Assembly ◽  
Large Scale ◽  
Crystal Size ◽  
Composite Films ◽  
Atomic Ratio ◽  
Layer By Layer ◽  
Spectroscopy Analysis ◽  
X Ray ◽  
Layer Method

CdS/TiO2 composite films with different Cd:Ti atomic ratio were prepared by a new straightforward particulate layer-by-layer method. Titanium dihydroxide and thiourea were used as precursors. Raman and X-ray photoelectron spectroscopy analysis for the composite films revealed that the TiO2 formed from titanium precursor retarded the crystal growth of CdS. Luminescence and UV–vis absorption spectra investigation showed that emission and absorption band of CdS/TiO2 blue shifted as crystal size of CdS decreased. Furthermore, hydrogen formation curves revealed that hydroxyl of CdS/TiO2 films plays an important role in water splitting reaction under both UV and visible light irradiations.

ALLOYING OF THIN Ag AND Au FILMS ON Pd(111) STUDIED BY HIGH-RESOLUTION PHOTOELECTRON SPECTROSCOPY OF SURFACE STATES

1996 ◽  
Vol 03 (05n06) ◽  
pp. 1783-1789 ◽  
Author(s):  
R. FISCHER ◽  
TH. FAUSTER
Keyword(s):  
High Resolution ◽  
Photoelectron Spectroscopy ◽  
Annealing Temperature ◽  
Three Dimensional ◽  
Surface States ◽  
Surface Region ◽  
Layer Growth ◽  
Alloy Formation ◽  
Layer By Layer ◽  
Island Growth

Alloy formation by annealing of thin Ag and Au films on Pd(111) is studied by high-resolution ultraviolet and two-photon photoelectron spectroscopy of surface states. Changes in the composition of the top layer of the surface alloys are reflected in the energy of the surface states. Above an annealing temperature of 500 K on both systems, the crystal-induced surface state shifts continuously from the occupied state of the adsorbate to the unoccupied state of the substrate. The continuous shift reflects the variable composition of the alloys in the surface region which depends on the initial coverage and the annealing temperature. The spectroscopy of the unoccupied image states permits the investigation of growth and morphology of deposited metal layers. Three-dimensional island growth, layer-by-layer growth, and surface alloy formation with metastable surface configurations and diffusion of the overlayer material into the bulk are identified.

Three-Dimensional Nanodot-Type Floating Gate Memory Fabricated by Bio-Layer-by-Layer Method

2011 ◽  
Vol 4 (8) ◽  
pp. 085004 ◽  
Author(s):  
Kosuke Ohara ◽  
Bin Zheng ◽  
Mutsunori Uenuma ◽  
Yasuaki Ishikawa ◽  
Kiyotaka Shiba ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Floating Gate ◽  
Layer By Layer ◽  
Layer Method ◽  
Floating Gate Memory

Preparation and properties of amorphous carbon oxynitrides a-CNxOy films made by a nitrogen radical sputter method and by the layer-by-layer method

2001 ◽  
Vol 675 ◽  
Author(s):  
Yohko Naruse ◽  
Shoji Nitta ◽  
Hitoe Habuchi
Keyword(s):  
Amorphous Carbon ◽  
Photoelectron Spectroscopy ◽  
Optical Transmittance ◽  
Oxygen Radical ◽  
Layer By Layer ◽  
Low Dielectric ◽  
Photothermal Deflection Spectroscopy ◽  
Layer Method ◽  
Spin Resonance ◽  
Nitrogen Radical

ABSTRACTWe have tried to prepare amorphous carbon oxynitrides (a-CNxOy)films by the oxygen radical treatment (ORT) of amorphous carbon nitrides (a-CNx) and also by the layer-by-layer method. Properties of a-CNxOy films were studied with X-ray photoelectron spectroscopy (XPS), photothermal deflection spectroscopy (PDS), ultraviolet-visible (UV-VIS) optical transmittance spectra, Raman spectra and electron spin resonance (ESR). Oxygen radical affects to a-CNx by etching, termination of defects and oxidation. A-CNxOy films are interesting for the application to luminescent materials and also to low dielectric consta nt materials.

Layer-by-Layer Method to Prepare Three-Dimensional Reduced Graphene Materials with Controlled Architectures Using SiO2 as a Sacrificial Template

2021 ◽  
Author(s):  
Alma D. Salazar-Aguilar ◽  
José Iván Rodriguez-Rodriguez ◽  
Alexis Piñeiro-García ◽  
Ferdinando Tristan ◽  
Gladis Judith Labrada-Delgado ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Layer By Layer ◽  
Sacrificial Template ◽  
Layer Method ◽  
Reduced Graphene

Angular Calibration of Ribosomal Subuntts in Factor Space

1990 ◽  
Vol 48 (1) ◽  
pp. 462-463
Author(s):  
Minakhi Pujari ◽  
Joachim Frank
Keyword(s):  
Three Dimensional ◽  
Carbon Layer ◽  
Uranyl Acetate ◽  
Particle Analysis ◽  
Factor Space ◽  
Multivariate Statistical ◽  
Ribosomal Subunits ◽  
Layer Method ◽  
Dimensional Reconstruction ◽  
Number Of Particles

In single-particle analysis of macromolecule images with the electron microscope, variations of projections are often observed that can be attributed to the changes of the particle’s orientation on the specimen grid (“rocking”). In the multivariate statistical analysis (MSA) of such projections, a single factor is often found that expresses a large portion of these variations. Successful angle calibration of this “rocking factor” would mean that correct angles can be assigned to a large number of particles, thus facilitating three-dimensional reconstruction.In a study to explore angle calibration in factor space, we used 40S ribosomal subunits, which are known to rock around an axis approximately coincident with their long axis. We analyzed micrographs of a field of these particles, taken with 20° tilt and without tilt, using the standard methods of alignment and MSA. The specimen was prepared with the double carbon-layer method, using uranyl acetate for negative staining. In the MSA analysis, the untilted-particle projections were used as active, the tilted-particle projections as inactive objects. Upon tilting, those particles whose rocking axes are parallel to the tilt axis will change their appearance in the same way as under the influence of rocking. Therefore, each vector, in factor space, joining a tilted and untilted projection of the same particle can be regarded as a local 20-degree calibration bar.

scholarly journals 3D Printing of High Viscosity Reinforced Silicone Elastomers

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2239
Author(s):  
Nicholas Rodriguez ◽  
Samantha Ruelas ◽  
Jean-Baptiste Forien ◽  
Nikola Dudukovic ◽  
Josh DeOtte ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Performance ◽  
New Technologies ◽  
Three Dimensional ◽  
High Viscosity ◽  
Layer By Layer ◽  
Silicone Elastomers ◽  
Uv Curable ◽  
Octet Truss ◽  
Tunable Mechanical Properties

Recent advances in additive manufacturing, specifically direct ink writing (DIW) and ink-jetting, have enabled the production of elastomeric silicone parts with deterministic control over the structure, shape, and mechanical properties. These new technologies offer rapid prototyping advantages and find applications in various fields, including biomedical devices, prosthetics, metamaterials, and soft robotics. Stereolithography (SLA) is a complementary approach with the ability to print with finer features and potentially higher throughput. However, all high-performance silicone elastomers are composites of polysiloxane networks reinforced with particulate filler, and consequently, silicone resins tend to have high viscosities (gel- or paste-like), which complicates or completely inhibits the layer-by-layer recoating process central to most SLA technologies. Herein, the design and build of a digital light projection SLA printer suitable for handling high-viscosity resins is demonstrated. Further, a series of UV-curable silicone resins with thiol-ene crosslinking and reinforced by a combination of fumed silica and MQ resins are also described. The resulting silicone elastomers are shown to have tunable mechanical properties, with 100–350% elongation and ultimate tensile strength from 1 to 2.5 MPa. Three-dimensional printed features of 0.4 mm were achieved, and complexity is demonstrated by octet-truss lattices that display negative stiffness.

scholarly journals Evolution of biobased and nanotechnology packaging – a review

2020 ◽  
Vol 35 (4) ◽  
pp. 491-515
Author(s):  
Tom Lindström ◽  
Folke Österberg
Keyword(s):  
Biodegradable Polymers ◽  
Food Packaging ◽  
Environmental Issues ◽  
Barrier Properties ◽  
Environmental Problems ◽  
Layer By Layer ◽  
Polyelectrolyte Complexes ◽  
Life Issues ◽  
Technological Developments ◽  
End Of Life Issues

AbstractThis review deals with the evolution of bio-based packaging and the emergence of various nanotechnologies for primary food packaging. The end-of life issues of packaging is discussed and particularly the environmental problems associated with microplastics in the marine environment, which serve as a vector for the assimilation of persistent organic pollutants in the oceans and are transported into the food chain via marine and wild life. The use of biodegradable polymers has been a primary route to alleviate these environmental problems, but for various reasons the market has not developed at a sufficient pace that would cope with the mentioned environmental issues. Currently, the biodegradable plastics only constitute a small fraction of the fossil-based plastic market. Fossil-based plastics are, however, indispensable for food safety and minimization of food waste, and are not only cheap, but has generally more suitable mechanical and barrier properties compared to biodegradable polymers. More recently, various nanotechnologies such as the use of nanoclays, nanocellulose, layer-by-layer technologies and polyelectrolyte complexes have emerged as viable technologies to make oxygen and water vapor barriers suitable for food packaging. These technological developments are highlighted as well as issues like biodegradation, recycling, legislation issues and safety and toxicity of these nanotechnologies.

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