Layer-by-layer modification of high surface curvature nanoparticles with weak polyelectrolytes using a multiphase solvent precipitation process

A computational and experimental estimation of the magnitude of forces acting in a high-intensity electric field on elements of nanoconstructions with a high surface curvature is made. Depending on the magnitude of the electric potential and vacuum conditions, these forces can vary both in magnitude and direction over a wide range. They can cause structural damage, as well as provoke unwanted electrical discharges. The possibilities of useful application of these effects are analyzed.

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Fabrication of Oxide Ceramics Dendrites for Porous Electrodes by Using Stereolithography

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/cicmt-2012-tp34 ◽

2012 ◽

Vol 2012 (CICMT) ◽

pp. 000152-000157 ◽

Cited By ~ 2

Author(s):

Satoko Tasaki ◽

Naoki Komori ◽

Soshu Kirihara

Keyword(s):

Heating Rate ◽

High Surface ◽

Ceramic Powder ◽

Numerical Data ◽

Porous Electrodes ◽

Oxide Ceramic ◽

Layer By Layer ◽

Oxide Ceramics ◽

Cross Sectional ◽

Aspect Ratios

Porous oxide ceramics such as zinc oxide are applied for dye sensitized solar cell. This device requires consideration of high surface area, mechanical strengths and porous networks. Thus, we focused on the dendrite structures constructed from micrometer order rods with coordination numbers of 4, 8, and 12. There perfectly controlled structures were fabricated by stereolithography. Variations of the aspect ratios (lattice length to diameter ratios) were adjusted to control the porosity in the range 50–80 vol. % by using computer graphic software. The dendrite models sliced into a series of cross sectional patterns with uniform thickness by using a stereolithographic file format convertor. These numerical data were transferred into the micro processing equipment. High viscosity slurry material was prepared by mixing oxide ceramic powder and photosensitive acrylic resin. This slurry was spread on a flat stage and smoothed. An ultraviolet laser beam was exposed over the deposited layer to create cross-sectional planes. Through layer-by-layer processes, solid components were fabricated. These precursors were dewaxed at 600°C for 2 h at a heating rate of 1.0°C/min and sintered at 1400°C for 2 h at a heating rate of 5.0°C/min in air. The oxide ceramics microstructure was observed using a scanning electron microscope.

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pH-Dependent Thermal Transitions in Hydrated Layer-by-Layer Assemblies Containing Weak Polyelectrolytes

Macromolecules ◽

10.1021/ma3020454 ◽

2012 ◽

Vol 45 (22) ◽

pp. 9169-9176 ◽

Cited By ~ 31

Author(s):

Ajay Vidyasagar ◽

Choonghyun Sung ◽

Kristen Losensky ◽

Jodie L. Lutkenhaus

Keyword(s):

Layer By Layer ◽

Thermal Transitions ◽

Hydrated Layer ◽

Ph Dependent ◽

Weak Polyelectrolytes

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Effect of High Surface Curvature on the Main Phase Transition of Supported Phospholipid Bilayers on SiO2Nanoparticles

Langmuir ◽

10.1021/la803630m ◽

2009 ◽

Vol 25 (6) ◽

pp. 3682-3691 ◽

Cited By ~ 54

Author(s):

Selver Ahmed ◽

Stephanie L. Wunder

Keyword(s):

Phase Transition ◽

High Surface ◽

Surface Curvature ◽

Phospholipid Bilayers ◽

Main Phase

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New Assembly Method for Cellulose Derived Graphene Quantum Dots-Sensitized Solar Cells

10.21203/rs.3.rs-242899/v1 ◽

2021 ◽

Author(s):

Savisha Mahalingam ◽

Kam Sheng Lau ◽

Azimah Omar ◽

Abreeza Manap ◽

Puvaneswaran Chelvanathan ◽

...

Keyword(s):

Quantum Dots ◽

Solar Cells ◽

Collection Efficiency ◽

High Surface ◽

Graphene Quantum Dots ◽

Layer By Layer ◽

Charge Collection Efficiency ◽

Oh Groups ◽

Assembly Method ◽

Sensitized Solar Cells

Abstract Unambiguously layer by layer (LBL) assembly of graphene quantum dots (GQDs) and dye (GQDs/dye) on TiO2 photoanode is the traditional and straightforward approach in the fabrication of graphene quantum dot-sensitized solar cells (QDSSCs). Unfortunately, limited light absorption and low affinity of GQDs to TiO2 surface shadow the advantages of LBL and constrains its practical application. Herein, a new strategy of mixture configuration (GQDs+dye) was investigated. A distinctive nanoporous honeycomb hexagonal carbon network of GQDs was found with fewer defects single crystalline structure, and an average size of 9.87 nm was produced from cellulose. Experimental results demonstrated that LBL exhibited the highest efficiency of 16.76 % under low illumination but a lower efficiency (1.43%) than the mixture method (2.91%) under standard light. The increased Jsc (5.075 mA/cm2) and high charge collection efficiency (0.96) in the mixture sample indicated enhanced electron collection at TiO2. The less -OH groups on TiO2 provides a good surface intact of GQDs and N719. In addition to that, the high surface potential (33.47 mV) of the premixed sample restricted the photogenerated electrons to go into a deep state, reducing back electron transfer. Therefore, mixture assembly of co-sensitization is an effective approach for light-harvesting in QDSSC.

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The Influence of Different Slicer Software on 3d Printing Products Accuracy and Surface Roughness

Jurnal Rekayasa Mesin ◽

10.21776/ub.jrm.2021.012.02.14 ◽

2021 ◽

Vol 12 (2) ◽

pp. 371-380

Author(s):

Sally Cahyati ◽

◽

Haris Risqy Aziz

Keyword(s):

Surface Roughness ◽

Additive Manufacturing ◽

3D Printing ◽

3D Model ◽

High Surface ◽

3D Printer ◽

Layer By Layer ◽

Additive Manufacturing Technology ◽

Printing Machine

Rapid Prototyping (RP) is a manufacturing process that produces a 3D model CAD to be a real product rapidly by using additive manufacturing technology. In this case, the product will print layer by layer uses a 3D printer machine. The 3D printer requires slicer software to convert CAD data into data that a 3D printer machine can read. Research is done to analyze the effect of three kinds of slicer software on 3D printing objects on the accuracy and surface roughness of the product. The 3D model CAD is sliced using three different slicer software, namely Ideamaker, Repetier Host, and Cura. The slice model result from each slicer will be printed on a 3D printer machine with the same process parameters to be compared. Then the product's dimensional and surface roughness will be measured to determine the effect of each slicer on product quality. The best quality of the product reflected the most suitable slicer software for the 3D printing machine that used. The best results achieved by Cura slicer because it has resulted in small dimensional deviations (max 0,0308±0,0079) and stabile high surface roughness of the product (max 1,585+059).

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Application of Nano particles by Layer-by-Layer (LBL) Deposition Technique to Improve the Functionality of Textiles

International Journal for Modern Trends in Science and Technology - RTT2020 ◽

10.46501/ijmtst0609s30 ◽

2020 ◽

Vol 06 (9S) ◽

pp. 183-191

Author(s):

Dr. Chet Ram Meena

Keyword(s):

Textile Industry ◽

High Surface ◽

High Surface Area ◽

Ultra Violet ◽

Nano Particles ◽

Layer By Layer ◽

Molecular Weights ◽

Coating Method ◽

Textile Polymers ◽

Fabric Surface

Few decades back, a Nano word with big promising has been precipitously implying itself into the world's realization and associates with everyday life, economics and globally consequences. Functionalization of textile polymers has been practiced by different techniques to confer new properties on to the fibre so as to enable their application in fields other than textile industry. Nanotechnology may deliver the better performances and functionality to the textile materials due to the high surface area and energy. Further, Nanoparticles can apply on the fabrics by coating method without affecting the comfort and feel of the fabrics. It has improved the various properties like ultra violet protection, antibacterial and stain proof etc. LBL techniques is used to produce a thin polymeric film in a controlled manner on a surface of fabrics by using of different size of molecular weights and charges of polyelectrolytes. The unique feature of this technique is that it forms a very thin layer on fabric surface (1-10 nm) as compared to other available techniques; thus, no deterioration of surface properties of the substrate on which they are deposited. Nano TiO2 and ZnO particles along with polyelectrolytes and produce PEM on the Nylon 66 substrate by using LBL technique to get the antimicrobial and Ultraviolet protection property.

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Optimization of UHV-CVD Thin Films for Gate Dielectric Applications

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.1351 ◽

2006 ◽

Vol 45 ◽

pp. 1351-1354

Author(s):

Bridget R. Rogers ◽

Zhe Song ◽

Robert D. Geil ◽

Robert A. Weller

Keyword(s):

Silicon Oxide ◽

Gate Dielectric ◽

High Surface ◽

Ex Situ ◽

Oxide Surfaces ◽

Layer By Layer ◽

Force Microscopy ◽

Transmission Electron ◽

Initial Stage ◽

Different Temperatures

In-situ and ex-situ spectroscopic ellipsometry (SE), atomic force microscopy (AFM), transmission electron microscopy (TEM), and time of flight medium energy backscattering (ToF MEBS), are used to investigate the properties of 30 and 60 Å ZrO2 films deposited at different temperatures on hydrogen terminated silicon (H-Si) and native silicon oxide surfaces. Results show that the initial-stage deposition of ZrO2 on H-Si and native silicon oxide surfaces are different. A 3-dimesional (3D) type nucleation process of ZrO2 on H-Si leads to high surface roughness films, while layer-by-layer deposition on native silicon oxide surfaces leads to smooth, uniform ZrO2 films. An interfacial layer, between the substrate and the metal oxide, is formed through two independent mechanisms: reaction between the starting surfaces and ZTB or its decomposition intermediates, and diffusion of reactive oxidants through the forming ZrO2 interfacial stack layer to react with the substrate.

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Modelling of Cusp Geometry in Additive Manufacturing Parts Using a Piece-Wise Polynomial

Volume 1A: 35th Computers and Information in Engineering Conference ◽

10.1115/detc2015-48009 ◽

2015 ◽

Author(s):

Farzaneh Kaji ◽

Ahmad Barari

Keyword(s):

Surface Roughness ◽

Additive Manufacturing ◽

Manufacturing Process ◽

High Surface ◽

3D Models ◽

Critical Issue ◽

Layer By Layer ◽

Layer Manufacturing ◽

Surface Angle ◽

Good Agreement

The final dimensional and geometric inaccuracies, and the resulting high surface roughness of the products have been the major problems in employing Additive Manufacturing (AM) technologies. Most of commonly used Additive manufacturing (AM) technologies are developed based on a layer-based manufacturing process to fabricate 3D models. The main critical issue in AM which reduces the surface integrity of the final products is the stair case error which happens due to layer by layer manufacturing process. A new method is presented to model the surface roughness of FDM parts based on considering a new geometry for the cusps. Variety of observations were conducted to model the exact geometry of the cusp. Considering that cusp geometry affects the surface roughness directly, the new geometry was used to predict the surface roughness distribution as a function of layer thickness and surface angle of the final FDM products. The model was validated by designing a set of experiments using 3D measurements of the surface roughness under high resolution surface topography device and the predicted model was in a good agreement with the experimental results.

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