Hydroxypropylsulfonation/Caproylation of Cornstarch to Enhance Its Adhesion to PLA Fibers for PLA Sizing

The impact of hydroxypropylsulfonation/caproylation on the adhesion of cornstarch to polylactic acid (PLA) fibers was investigated for ameliorating the applications such as PLA sizing. The hydroxypropylsulfonated and caproylated cornstarch (HCS) samples with different degrees of substitution (DS) were synthesized by a hydroxypropylsulfonation of acid-converted cornstarch (ACS) with 3-chloro-2-hydroxy-1-propanesulfonic acid sodium salt (CHPS-Na) and subsequently a caproylation with caproic anhydride (CA). The HCS granules were characterized by Fourier transform infrared spectroscopic and scanning electron microscopy. The adhesion was evaluated by measuring the bonding forces of the PLA roving impregnated. The mechanical behaviors of the adhesive layers were estimated by determining the properties of the films. The results of adhesion measurement were also analyzed especially through the wetting and spreading of the paste on the fiber surfaces, as well as the failure type, internal stress and mechanical behaviors of the adhesive layers among fibers. Additionally, apparent viscosity and its stability of the pastes were also determined. It was found that hydroxypropylsulfonation/caproylation was not only able to obviously improve the adhesion of ACS to PLA fibers, but also capable of further improving the adhesion of hydroxypropylsulfonated starch (HS) to the fibers. With the rise in the total DS, the adhesion gradually increased. The two substituents improved the wetting and spreading, reduced the internal stress, lowered the probabilities of interfacial failure and cohesive failure, decreased the film brittleness, and increased the van der Waals force at the interfaces. Moreover, the HCS samples with a stability of above 85% could meet the demand on the stability for sizing. Considering the experimental results of the adhesion and the analysis of the results, HCS showed potential in the application of PLA sizing.

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A new species of Cribraria (Myxomycetes) from Australia

Novosti sistematiki nizshikh rastenii ◽

10.31111/nsnr/2018.52.2.379 ◽

2018 ◽

Vol 52 (2) ◽

pp. 379-385 ◽

Cited By ~ 1

Author(s):

S. L. Stephenson ◽

Yu. K. Novozhilov ◽

P. Wellman

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

Lemon Yellow ◽

Moist Chamber ◽

Light Yellow ◽

Dark Violet ◽

The Stability ◽

A New Species ◽

Scanning Electron

A new species of Cribraria, described herein as C. bicolor, appeared in moist chamber cultures on samples of the bark of Eucalyptus sp. collected at two localities in Australia. The morphology of representative specimens was examined by light and scanning electron microscopy, and micrographs of relevant morphological details of sporocarps and spores are provided. The species has a number of distinct and unique morphological features, including a glossy bright-violet globose sporotheca and a two-colored long stalk which is bright-red over the lower one-third and light yellow or lemon-yellow over the upper two-thirds. The combination of these characteristics as well as a shallow calyculus which is dark-violet when viewed under a dissecting microscope and bright red in transmitted light when mounted in lactophenol makes C. bicolor a well-defined morphospecies when compared to all other species of Cribraria. The stability of the taxonomic characters of the species was confirmed by an examination of a number of specimens.

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The force effects of two types of polyethylene terephthalate glyc-olmodified clear aligners immersed in artificial saliva

Scientific Reports ◽

10.1038/s41598-021-89425-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Biao Xiang ◽

Xingxing Wang ◽

Gang Wu ◽

Yichen Xu ◽

Menghan Wang ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Polyethylene Terephthalate ◽

Artificial Saliva ◽

Orthodontic Force ◽

The Mean ◽

The Stability ◽

Scanning Electron

AbstractNumerous factors can influence the force exerted by clear aligners on teeth. This study aimed to investigate the stability of the force delivered by two different material appliances. 90 clear aligners with 2 materials and three different activations were designed and fabricated. Then, a device was employed to measure the force generated by the two types of PET-G material appliances immersed in artificial saliva for 0, 3, 7, 10, 14 days. Scanning electron microscopy was applied to observe the morphologic alterations on the aligner surfaces, respectively. The forces generated by different activation appliance exhibited differently, 0.0 mm < 0.1 mm < 0.2 mm. In addition, increasing the immersion times and the orthodontic force also decreased, but the forces decreased differently. Compared with the forces of conventional PETG appliances with 0.20 mm activation, the modified PETG appliances with the same activation exhibited significantly higher mean force. When comparing the mean force for modified PETG appliances after 10 and 14 days with conventional PETG appliances, the delivery forces exhibited significant differences (P < 0.05). The force delivered by both materials decreased obviously following artificial saliva immersion, and the force generated by modified aligners exhibited better stability than conventional aligners.

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Effect of inorganic nanofillers on the impact behavior and fracture probability of industrial high-density polyethylene nanocomposite

Journal of Composite Materials ◽

10.1177/0021998317746477 ◽

2017 ◽

Vol 52 (18) ◽

pp. 2431-2442 ◽

Cited By ~ 4

Author(s):

Harun Sepet ◽

Necmettin Tarakcioglu ◽

RDK Misra

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

High Density Polyethylene ◽

Fracture Probability ◽

High Density ◽

Impact Behavior ◽

Inorganic Filler ◽

Melt Mixing ◽

The Impact ◽

Scanning Electron

The main purpose of this work is to study how the morphology of nanofillers and dispersion and distribution level of inorganic nanofiller influence the impact behavior and fracture probability of inorganic filler filled industrial high-density polyethylene nanocomposites. For this study, nanoclay and nano-CaCO3 fillers–high-density polyethylene mixings (0, 1, 3, 5 wt.% high-density polyethylene) was prepared by melt-mixing method using a compounder system. The impact behavior was examined by charpy impact test, scanning electron microscopy, and probability theory and statistics. The level of the dispersion was characterized with scanning electron microscopy energy dispersive X-ray spectroscopy analysis. The results showed rather good dispersion of both of inorganic nanofiller, with a mixture of exfoliated and confined morphology. The results indicated that the impact strength of the industrial nanocomposite decreased with the increase of inorganic particulate content. The impact reliability of the industrial nanocomposites depends on the type of nanofillers and their dispersion and distribution in the matrix.

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Identification of Nd163 phase in melt-textured NdBa2Cu3O7−δ bulk samples

Journal of Materials Research ◽

10.1557/jmr.2003.0288 ◽

2003 ◽

Vol 18 (9) ◽

pp. 2050-2054 ◽

Cited By ~ 4

Author(s):

Marcello Gombos ◽

Vicente Gomis ◽

Anna Esther Carrillo ◽

Antonio Vecchione ◽

Sandro Pace ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Optical Microscopy ◽

Room Temperature ◽

Polarized Light ◽

Energy Dispersive ◽

X Ray ◽

Spontaneous Formation ◽

The Stability ◽

Scanning Electron

In this work, we report on the observation of Nd1Ba6Cu3O10,5 (Nd163) phase of the NdBaCuO system in melt-textured Nd123 bulk samples grown from a mixture of Nd123 and Nd210 phase powders. The observation was performed with polarized light optical microscopy and scanning electron microscopy–energy dispersive x-ray analyses. Images of the identified phase crystals show an aspect quite different from Nd422 crystals. Unexpectedly, Nd163 was individuated, even in “pure” Nd123 samples. Moreover, after long exposure to air, Nd163 disappeared completely in samples synthesized from powders containing Nd210. Thermogravimetry analyses of powders show that the stability of this phase in air is limited to temperatures higher than 900 °C, so Nd163 is unstable and highly reactive at room temperature. Moreover, an explanation of the observation of Nd163 in Nd210 free samples, based on the spontaneous formation of Nd163 phase in a Nd123 melt, is proposed.

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Study on the Calamine/Sodium Alginate Modified Viscose Fiber

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.418-420.192 ◽

2011 ◽

Vol 418-420 ◽

pp. 192-195

Author(s):

Dong Qi Liu ◽

Ying Liu ◽

Shu Fa Han ◽

Yu Feng Zhang ◽

Cui Yu Yin

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Sodium Alginate ◽

Mechanical Performance ◽

Viscose Fiber ◽

Alginate Solution ◽

Fiber Properties ◽

Injection Methods ◽

The Stability ◽

Scanning Electron

In this article we successfully prepared calamine / sodium alginate viscose fiber. Good dispersion and stability of the modified solution was prepared by dispersing calamine in alkaline solution of sodium alginate, and then mixed it with viscose spinning solution by spinning injection methods. Moreover, the stability of calamine / sodium alginate solution, the effect of concentration of calamine on the fiber properties is studied in this paper. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and physical mechanical performance are test to characterize the structure and the performance of the calamine / sodium alginate viscose fiber.

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The Impact Properties of a Polyurethane Composite Filled with Clay

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.197-198.1100 ◽

2011 ◽

Vol 197-198 ◽

pp. 1100-1103

Author(s):

Jian Li

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Mechanical Analysis ◽

Impact Testing ◽

Impact Properties ◽

Polyurethane Composite ◽

The Matrix ◽

The Impact ◽

Scanning Electron

A polyurethane/clay (PU/clay) composite was synthesized. The microstructure of the composite was examined by scanning electron microscopy. The impact properties of the composite were characterized by impact testing. The study on the structure of the composite showed that clays could be dispersed in the polymer matrix well apart from a few of clusters. The results from mechanical analysis indicated that the impact properties of the composite were increased greatly in comparison with pure polyurethane. The investigation on the mechanical properties showed that the impact strength could be obviously increased by adding 20 wt% (by weight) clay to the matrix.

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SILVER NANOPARTICLES FROM MEDICINALLY IMPORTANT EUPHORBIA CYATHOPHORA EXTRACT: BIOSYNTHESIS, CHARACTERIZATION, AND ANTICANCER ACTIVITY.

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i2.22216 ◽

2018 ◽

Vol 11 (2) ◽

pp. 154

Author(s):

Robert Lotha ◽

Aravind Sivasubramanian ◽

Meenakshi Sundaram Muthuraman

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Cell Line ◽

Aqueous Extract ◽

Visible Spectroscopy ◽

X Ray ◽

Transmission Electron ◽

The Stability ◽

Ht 29 ◽

Scanning Electron

Objective: The present study was aimed at the biosynthesis of silver nanoparticles (AgNPs) using aqueous extract of Euphorbia cyathophora leavesand testing their anticancer potential using HT-29 cell line model.Methods: Green synthesis of silver nanoparticles was obtained with the aqueous extract of E. cyathophora. The synthesized nanoparticles wereconfirmed initially by ultraviolet-visible spectroscopy. Further, scanning electron microscopy, transmission electron microscopy, and X-Ray diffractionstudies also ensured the presence of silver nanoparticles. Zeta potential studies revealed the stability of the silver nanoparticles.Results: Antioxidant and anticancer studies of the nanoparticles against HT-29 cell line exhibited remarkable results.Conclusion: This ensures that the synthesized nanoparticles play an important role in medicinal biology.

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Microstructure–Property Relationship of Polyurethane Foams Modified with Baltic Sea Biomass: Microcomputed Tomography vs. Scanning Electron Microscopy

Materials ◽

10.3390/ma13245734 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5734

Author(s):

Paulina Kosmela ◽

Jan Suchorzewski ◽

Krzysztof Formela ◽

Paweł Kazimierski ◽

Józef Tadeusz Haponiuk ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Baltic Sea ◽

Thermal Insulation ◽

Reference Sample ◽

Microcomputed Tomography ◽

Polyurethane Foams ◽

Relationship Of ◽

The Impact ◽

Scanning Electron

In this paper, novel rigid polyurethane foams modified with Baltic Sea biomass were compared with traditional petro-based polyurethane foam as reference sample. A special attention was focused on complex studies of microstructure, which was visualized and measured in 3D with high-resolution microcomputed tomography (microCT) and, as commonly applied for this purpose, scanning electron microscopy (SEM). The impact of pore volume, area, shape and orientation on appearance density and thermal insulation properties of polyurethane foams was determined. The results presented in the paper confirm that microcomputed tomography is a useful tool for relatively quick estimation of polyurethane foams’ microstructure, what is crucial especially in the case of thermal insulation materials.

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Cushion Mechanism of Goat Hoof Bulb Tissues

Applied Bionics and Biomechanics ◽

10.1155/2019/3021576 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Weijun Tian ◽

Hai Liu ◽

Qi Zhang ◽

Bo Su ◽

Wei Xu ◽

...

Keyword(s):

Electron Microscopy ◽

Composite Structures ◽

Epidermal Layer ◽

Normal Model ◽

The Finite Element Method ◽

Dermal Layer ◽

Subcutaneous Tissues ◽

The Impact ◽

Dermal Papillae ◽

Scanning Electron

The hoof bulb sections of white goats were observed via scanning electron microscopy and stereomicroscopy in order to explore the cushion mechanism in the bulb tissue microstructures of hoofed animals. The hoof bulbs consisted of multilayer tissues, including an epidermal layer, a dermal layer, and subcutaneous tissues from outside to inside. A bionic model based on hoof bulb tissue composite structures was built with a normal model as the control. The microcosmic mechanics of the bulb tissues was analyzed via the finite element method. Simulations showed that when the bionic model was impacted by the top plates at the speed of 1-10 m/s, stress was concentrated in the epidermal layer and uniformly distributed in the dermal layer and dermal papillae, which effectively reduced the impact onto the ground. The cornified epidermal layer can resist the instant impact onto the ground, while the dermal papillae embedded in the dermal layer can store, release, and dissipate the impulsive energy, and the three parts synergically act in the cushion.

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Effects of Droplet-Vitrification Cryopreservation Based on Physiological and Antioxidant Enzyme Activities ofBrassidiumShooting Star Orchid

The Scientific World JOURNAL ◽

10.1155/2015/961793 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

Safrina Rahmah ◽

Safiah Ahmad Mubbarakh ◽

Khor Soo Ping ◽

Sreeramanan Subramaniam

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Liquid Nitrogen ◽

Enzyme Activities ◽

Structural Changes ◽

Total Soluble Protein ◽

Antioxidant Enzyme Activities ◽

Droplet Vitrification ◽

The Impact ◽

Scanning Electron

Protocorm-like bodies (PLBs) ofBrassidiumShooting Star orchid were successfully cryopreserved using droplet-vitrification method. Vitrification based cryopreservation protocol is comprised of preculture, osmoprotection, cryoprotection, cooling, rewarming, and growth recovery and each and every step contributes to the achievement of successful cryopreservation. In order to reveal the lethal and nonlethal damage produced by cryopreservation, histological observation, scanning electron microscopy (SEM), and biochemical analysis were carried out in both cryopreserved and noncryopreserved PLBs ofBrassidiumShooting Star orchid comparing with the control PLBs stock culture. Histological and scanning electron microscopy analyses displayed structural changes in cryopreserved PLBs due to the impact of cryoinjury during exposure to liquid nitrogen. Total soluble protein significantly increased throughout the dehydration process and the highest value was achieved when PLBs were stored in liquid nitrogen. Ascorbate peroxidase (APX) and catalase (CAT) showed the highest enzyme activities in both dehydration and cryostorage treatments indicating that stress level of PLBs was high during these stages.

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