Characterization of high strength cement paste with pristine graphite and heptane-graphite emulsion

This research emphasizes the importance of the acid cleaning prior to the phosphate development on high-strength steel rods. It compares the phosphate properties achieved after different acid-pickling conditions. The most common inorganic acids were considered in this study. Additionally, taking into account the environmental and safety concerns of these acids, the assessment of a less harmful organic acid is presented. This study revealed significant differences in the coating morphology and chemical composition whereas no great changes were found in terms of the coating weight or porosity. Thus, hydrochloric and sulfuric acid promote the growth of a Fe-enriched phosphate layer with a less conductive character that is not developed after the pickling with phosphoric acid. The phosphate developed after the citric acid pickling is comparable to that developed after the inorganic acids although with a porosity slightly higher. The temperature of the citric acid bath is an important parameter that affects to the phosphate appearance, composition, and porosity.

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Preparation and characterization of high strength and high modulus PVA fiber via dry‐wet spinning with cross‐linking of boric acid

Journal of Applied Polymer Science ◽

10.1002/app.51394 ◽

2021 ◽

pp. 51394

Author(s):

Xinqiu Hong ◽

Junwei He ◽

Liming Zou ◽

Yanli Wang ◽

Yan Vivian Li

Keyword(s):

Boric Acid ◽

High Strength ◽

Wet Spinning ◽

Cross Linking ◽

High Modulus ◽

Pva Fiber

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Facile Synthesis and Characterization of Palm CNF-ZnO Nanocomposites with Antibacterial and Reinforcing Properties

International Journal of Molecular Sciences ◽

10.3390/ijms22115781 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5781

Author(s):

Janarthanan Supramaniam ◽

Darren Yi Sern Low ◽

See Kiat Wong ◽

Loh Teng Hern Tan ◽

Bey Fen Leo ◽

...

Keyword(s):

Plant Biomass ◽

Cellulose Nanofibers ◽

High Strength ◽

Salmonella Typhi ◽

Particle Sizes ◽

Mechanical Reinforcement ◽

Uniform Size ◽

Preparation Methods ◽

Potential Applications

Cellulose nanofibers (CNF) isolated from plant biomass have attracted considerable interests in polymer engineering. The limitations associated with CNF-based nanocomposites are often linked to the time-consuming preparation methods and lack of desired surface functionalities. Herein, we demonstrate the feasibility of preparing a multifunctional CNF-zinc oxide (CNF-ZnO) nanocomposite with dual antibacterial and reinforcing properties via a facile and efficient ultrasound route. We characterized and examined the antibacterial and mechanical reinforcement performances of our ultrasonically induced nanocomposite. Based on our electron microscopy analyses, the ZnO deposited onto the nanofibrous network had a flake-like morphology with particle sizes ranging between 21 to 34 nm. pH levels between 8–10 led to the formation of ultrafine ZnO particles with a uniform size distribution. The resultant CNF-ZnO composite showed improved thermal stability compared to pure CNF. The composite showed potent inhibitory activities against Gram-positive (methicillin-resistant Staphylococcus aureus (MRSA)) and Gram-negative Salmonella typhi (S. typhi) bacteria. A CNF-ZnO-reinforced natural rubber (NR/CNF-ZnO) composite film, which was produced via latex mixing and casting methods, exhibited up to 42% improvement in tensile strength compared with the neat NR. The findings of this study suggest that ultrasonically-synthesized palm CNF-ZnO nanocomposites could find potential applications in the biomedical field and in the development of high strength rubber composites.

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Preparation and characterization of double network hydrogel with high-strength and self-healing

Materials Today Communications ◽

10.1016/j.mtcomm.2021.102450 ◽

2021 ◽

pp. 102450

Author(s):

Shubin Li ◽

Xiao Wang ◽

Jiang Zhu ◽

Zhenyu Wang ◽

Lu Wang

Keyword(s):

High Strength ◽

Self Healing ◽

Double Network

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Quantitative Characterization of Hydration of Cement Pastes by Rietveld Phase Analysis and Thermoanalysis

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.539.19 ◽

2013 ◽

Vol 539 ◽

pp. 19-24 ◽

Cited By ~ 1

Author(s):

Yong Qi Wei ◽

Wu Yao

Keyword(s):

Phase Analysis ◽

Cement Paste ◽

Rietveld Method ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Quantitative Characterization ◽

Cement Pastes ◽

Hydration Mechanism ◽

Spot Check

The quantitative characterization of hydration of cement pastes has always been one of focuses of researchers’ attention. Rietveld phase analysis (RPA), a combination of quantitative X-ray diffraction (QXRD) and the Rietveld method, supplies a tool of an enormous potential for that. Although a few of related researches were conducted by RPA, the reported attention was not paid to the neat cement paste with a low w/c ratio. Therefore, this work aimed at the quantitative study on hydration of such a cement paste chiefly by this method, meanwhile, cooperated with the hyphenated technique of thermogravimetry with differential scanning calorimetry (TG-DSC), as a spot check. Results indicated that RPA was a reliable method in quantitatively characterizing hydration of cement pastes, and gave a clear decription of evolution of all main crystal phases in cement pastes; and that the evolution of monosulphate(Afm_12) was also able to be tracked quantitatively. This will help to understand better the hydration mechanism of cement pastes, as well as to investigate quantitatively effects of mineral and chemical admixtures on hydration of composite cementitious systems.

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Synthesis and Characterization of Porous ZrO2-Y2O3-TiO2 Ceramics Prepared by Coprecipitation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.727-728.1387 ◽

2012 ◽

Vol 727-728 ◽

pp. 1387-1392 ◽

Cited By ~ 1

Author(s):

Luan M. Medeiros ◽

Fernando S. Silva ◽

Juliana Marchi ◽

Walter Kenji Yoshito ◽

Dolores Ribeiro Ricci Lazar ◽

...

Keyword(s):

Ceramic Composite ◽

High Strength ◽

Ceramic Composites ◽

Rice Starch ◽

X Ray Diffraction ◽

Zirconia Ceramics ◽

Pore Former ◽

X Ray ◽

Cold Pressed

Zirconium dioxide (zirconia) ceramics are known by its high strength and toughness and titanium dioxide (titania) ceramics has outstanding surface properties. The ceramic composite formed between the two oxides are expected to have advantages of both ceramics, especially when its surface area is increased by pores. In this work, ceramic composites of ZrO2-Y2O3-TiO2were synthesized by coprecipitation and rice starch was added as pore former in 10, 20 and 30 wt%. Powders were cold pressed as cylindrical pellets and sintered at 1500 °C for 01 hour and ceramics were characterized by techniques as Archimedes method for density measurements, X-ray diffraction and scanning electron microscopy. Results showed that pores are inhomogeneously distributed through ceramic bodies.

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