Irregular Shapes: Randomness in Fractal Constructions

1992 ◽  
pp. 379-432
Author(s):  
Heinz-Otto Peitgen ◽  
Hartmut Jürgens ◽  
Dietmar Saupe
Keyword(s):  
Irregular Shapes

A quantitative image analysis method for the determination of cocontinuity in polymer blends

1993 ◽  
Vol 51 ◽  
pp. 894-895
Author(s):  
William A. Heeschen
Keyword(s):  
Image Analysis ◽  
Polymer Blends ◽  
Quantitative Measurement ◽  
Morphological Evolution ◽  
Phase Ratio ◽  
Irregular Shapes ◽  
Quantitative Image ◽  
Discrete Domains ◽  
A Domains

Two new morphological measurements based on digital image analysis, CoContinuity and CoContinuity Balance, have been developed and implemented for quantitative measurement of morphology in polymer blends. The morphology of polymer blends varies with phase ratio, composition and processing. A typical morphological evolution for increasing phase ratio of polymer A to polymer B starts with discrete domains of A in a matrix of B (A/B < 1), moves through a cocontinuous distribution of A and B (A/B ≈ 1) and finishes with discrete domains of B in a matrix of A (A/B > 1). For low phase ratios, A is often seen as solid convex particles embedded in the continuous B phase. As the ratio increases, A domains begin to evolve into irregular shapes, though still recognizable as separate domains. Further increase in the phase ratio leads to A domains which extend into and surround the B phase while the B phase simultaneously extends into and surrounds the A phase.

scholarly journals Impact of Liposomal Drug Formulations on the RBCs Shape, Transmembrane Potential, and Mechanical Properties

2021 ◽  
Vol 22 (4) ◽  
pp. 1710
Author(s):  
Sylwia Cyboran-Mikołajczyk ◽  
Przemysław Sareło ◽  
Robert Pasławski ◽  
Urszula Pasławska ◽  
Magdalena Przybyło ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Side Effects ◽  
Blood Cells ◽  
Transmembrane Potential ◽  
Drug Formulations ◽  
Liposomal Drug ◽  
Irregular Shapes ◽  
Liposomal Formulations ◽  
Current Therapies ◽  
Negative Side Effects

Liposomal technologies are used in order to improve the effectiveness of current therapies or to reduce their negative side effects. However, the liposome–erythrocyte interaction during the intravenous administration of liposomal drug formulations may result in changes within the red blood cells (RBCs). In this study, it was shown that phosphatidylcholine-composed liposomal formulations of Photolon, used as a drug model, significantly influences the transmembrane potential, stiffness, as well as the shape of RBCs. These changes caused decreasing the number of stomatocytes and irregular shapes proportion within the cells exposed to liposomes. Thus, the reduction of anisocytosis was observed. Therefore, some nanodrugs in phosphatidylcholine liposomal formulation may have a beneficial effect on the survival time of erythrocytes.

scholarly journals Clustering Irregular Shapes Using High-Order Neurons

2000 ◽  
Vol 12 (10) ◽  
pp. 2331-2353 ◽  
Author(s):  
H. Lipson ◽  
H. T. Siegelmann
Keyword(s):  
Synaptic Weight ◽  
Hebbian Learning ◽  
Second Order ◽  
High Order ◽  
Maximum Correlation ◽  
Overlapping Clusters ◽  
Homogeneous Coordinates ◽  
Irregular Shapes ◽  
Data Clusters ◽  
Iris Data

This article introduces a method for clustering irregularly shaped data arrangements using high-order neurons. Complex analytical shapes are modeled by replacing the classic synaptic weight of the neuron by high-order tensors in homogeneous coordinates. In the first- and second-order cases, this neuron corresponds to a classic neuron and to an ellipsoidal-metric neuron. We show how high-order shapes can be formulated to follow the maximum-correlation activation principle and permit simple local Hebbian learning. We also demonstrate decomposition of spatial arrangements of data clusters, including very close and partially overlapping clusters, which are difficult to distinguish using classic neurons. Superior results are obtained for the Iris data.

Performance of Polishing Slurries containing Silica Particles grown by Sol-Gel Method

2000 ◽  
Vol 613 ◽  
Author(s):  
Sun Hyuk Bae ◽  
Jae-Hyun So ◽  
Seung-Man Yang ◽  
Do Hyun Kim
Keyword(s):  
Fumed Silica ◽  
Sol Gel ◽  
Particle Growth ◽  
Silica Particles ◽  
Gel Method ◽  
Sol Gel Method ◽  
Irregular Shapes ◽  
Wafer Polishing ◽  
Transmission Electron ◽  
Silica Slurry

ABSTRACTSilica slurry used as abrasives in wafer polishing process is made by dispersing silica particles in an alkali solution. Since commercially available colloidal or fumed silica particles need some modifications to be directly used as abrasive slurry due to their small sizes, irregular shapes or broad size distribution, we have prepared silica abrasives by particle growth of fumed silica or colloidal silica as seeds by sol-gel method. Silica slurries prepared by this step-wise growth from commercial seeds were tested using one-armed polisher for the comparison with commercial slurries and showed the performance comparable to commercial slurries. Microstructures of polishing slurries were investigated using transmission electron microscopy and ARES rheometer. From the result, stability of the slurry was found to be more important than the primary particle sizes for the polishing performance.

Flexible silicon nanowires sensor for acetone detection on plastic substrates

2021 ◽  
Author(s):  
Kuibo Lan ◽  
Zhi Wang ◽  
Xiaodong Yang ◽  
Junqing Wei ◽  
Yuxiang Qin ◽  
...  
Keyword(s):  
Silicon Nanowires ◽  
High Performance ◽  
Underlying Mechanism ◽  
Environmental Safety ◽  
Cmos Process ◽  
Plastic Substrates ◽  
Irregular Shapes ◽  
Good Potential ◽  
Mechanical Bending ◽  
Acetone Detection

Abstract Acetone commonly exists in daily life and is harmful to human health, therefore the convenient and sensitive monitoring of acetone is highly desired. In addition, flexible sensors have the advantages of light-weight, conformal attachable to irregular shapes, etc. In this study, we fabricated high performance flexible silicon nanowires (SiNWs) sensor for acetone detection by transferring the monocrystalline Si film and metal-assisted chemical etching method on polyethylene terephthalate (PET). The SiNWs sensor enabled detection of gaseous acetone with a concentration as low as 0.1 parts per million (ppm) at flat and bending states. The flexible SiNWs sensor was compatible with the CMOS process and exhibited good sensitivity, selectivity and repeatability for acetone detection at room temperature. The flexible sensor showed performance improvement under mechanical bending condition and the underlying mechanism was discussed. The results demonstrated the good potential of the flexible SiNWs sensor for the applications of wearable devices in environmental safety, food quality, and healthcare.

Wettability measurements of irregular shapes with Wilhelmy plate method

2018 ◽  
Vol 427 ◽  
pp. 273-280 ◽  
Author(s):  
Jaehyung Park ◽  
Ugur Pasaogullari ◽  
Leonard Bonville
Keyword(s):  
Plate Method ◽  
Irregular Shapes ◽  
Wilhelmy Plate ◽  
Wilhelmy Plate Method

scholarly journals Bio-conjugated silver nano-materials and shape-directing role of cetyltrimethylammonium bromide

2013 ◽  
Vol 2 (1) ◽  
pp. 57-67 ◽  
Author(s):  
Zaheer Khan ◽  
Qamer Faisal ◽  
Rabia Ahmad
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Electron Microscopic ◽  
Tem Analysis ◽  
Alstonia Scholaris ◽  
Irregular Shapes ◽  
Transmission Electron ◽  
Electron Microscopic Technique ◽  
Visible Spectra ◽  
Transmission Electron Microscopic ◽  
20 Nm

Conventional UV-visible spectrophotometric and transmission electron microscopic technique were used to determine the morphology of silver nanoplates (AgNP) using Alstonia scholaris aqueous leaves extract for the first time. The visible spectra showed the presence of three well defined surface plasmon absorption (SRP) bands at 500, 550 and 675 nm which attributed to the anisotropic growth of Ag-nanoplates. Transmission electron microscopic (TEM) analysis of AgNP showed formation of truncated triangular, polyhedral with some irregular shapes nanoplates in the size range 7-20 nm. Cetyltrimethylammonium bromide (CTAB) has no significant effect on the shape of the spectra, position of SRP bands, size and the size distribution of AgNP. Effects of various [CTAB] were also discussed in the green extra-cellular synthesis of AgNP using Alstonia scholaris leaves extract.

scholarly journals Fluorescent Tagging of Polymer Particles with PBN for the Detection of Microplastics in Personal Care Goods

2021 ◽  
Vol 43 (8) ◽  
pp. 567-577
Author(s):  
Eun-Hee Lee ◽  
Sangwon Lee ◽  
Seung-Woo Lee
Keyword(s):  
Primary Source ◽  
Ethylene Vinyl Acetate ◽  
Attenuated Total Reflection ◽  
Personal Care ◽  
Polymer Particles ◽  
Plastic Pollution ◽  
Irregular Shapes ◽  
Detection And Identification ◽  
Single Use ◽  
Fluorescent Tagging

Objectives : Plastic pollution has been aggravated due to the massive use of disposable products and single-use face masks since the coronavirus disease (COVID-19) pandemic. There is growing interest regarding detection and identification of plastic pollution in daily life. The aim of this study is (1) to investigate suitability of a fluorescent labelling method for the detection of polymers, (2) to detect microplastics in personal care goods, and (3) to identify the detected plastic particles.Methods : In order to detect plastic particles in real samples, a 1-pyrenebutyric acid N-hydroxysuccinimidyl ester (PBN) fluorophore was used as a dye for staining plastic particles. First, the capability of PBN was evaluated by staining a model polymer of polyethylene (PE) particles, and its desorption and photobleaching was also investigated. Using the optimum staining condition, microplastics were detected in a laboratory-controlled sample and commercially available products, specifically in cleansers, scrubs, and toothpastes. Finally, the detected microplastics were identified using an attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) analysis.Results and Discussion : The PE particles fluoresced blue light after being stained with PBN at a concentration of 100 μg/mL for 3-5 min without post treatments (e.g., fixation and drying), but the particles should be detected within 24 h due to the photobleaching of PBN. The desorption of PBN fluorophore occurred when the stained PE particles were washed with 25% acetone rather than rinse-off with deionized (DI) water. All of the tested personal care goods contained plastic particles and various sizes and shapes (e.g., spherical, rounded, and irregular shapes) of particles were found in different types and brands of products. The detected particles were identified as PE, polypropylene (PP), polycarbonate (PC), ethylene vinyl acetate (EVA), polystyrene (PS), and polyvinyl chloride (PVC) polymers.Conclusions : The PBN was shown to effectively stain polymer particles and it allowed visual identification of microplastics in personal care goods. Various types and sizes of polymers were included into the commercially available products as ingredients, indicating a primary source of plastic pollution in aquatic environment.

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