scholarly journals Corrigendum to “Cellulose nanofibrils with and without nanosilica for the performance enhancement of portland cement systems” [Constr. Build. Mater. 285 (2021) 121547]

2022 ◽  
Vol 319 ◽  
pp. 126046
Author(s):  
Kavya S. Kamasamudram ◽  
Warda Ashraf ◽  
Eric N. Landis
Keyword(s):  
Portland Cement ◽  
Performance Enhancement ◽  
Cellulose Nanofibrils

Cellulose Nanocomposites for Performance Enhancement of Ordinary Portland Cement-Based Materials

2020 ◽  
pp. 036119812095842
Author(s):  
Kavya S. Kamasamudram ◽  
Warda Ashraf ◽  
Eric N. Landis
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Portland Cement ◽  
Cement Paste ◽  
Ordinary Portland Cement ◽  
Performance Enhancement ◽  
Mechanical Performance ◽  
Early Stage ◽  
Microstructural Development ◽  
Hydration Kinetics

Cellulose nanofibril (CNF) with a high aspect ratio, elastic modulus, tensile strength, and reactive surface area is a promising nanomaterial for improving the chemo-mechanical properties of cementitious matrixes. CNFs are typically less than 0.2 mm in length and 50 nm in width, and are extracted from plants and trees. This study investigated the potential application of three types of CNF for enhancing the performance of ordinary Portland cement (OPC) pastes: pure CNF (PCNF), silica coated CNF (SCNF), and lignin-containing CNF (LCNF). The performance of the cement pastes was monitored for cement paste workability, hydration kinetics, microstructural development, and mechanical performance (compressive strength and flexural strength). The dispersion stability of CNFs measured through zeta potential showed a better dispersion for SCNF when compared with PCNF and LCNF in varied alkaline mediums. The better stability of SCNF also resulted in improved workability of the cement paste mixtures containing this type of cellulose. All of the cellulose nanomaterials accelerated the cement hydration at the early stage as a result of the nucleation effect. Such an acceleration effect was slightly higher for SCNF because of the presence of silica nanoparticles. The addition of 0.1% SCNF increased the compressive strength (90 days) by 13% when compared with the control batch and 10% compared with the PCNF batch. The addition of 0.1% of PCNF enhanced the flexural strength by 70% followed by LCNF with 40% improvement. SCNF showed little to no effect on the flexural strength.

scholarly journals Recycling Blast Furnace Ferronickel Slag as a Replacement for Paste in Mortar: Formation of Carboaluminate, Reduction of White Portland Cement, and Increase in Strength

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2687
Author(s):  
Qingfeng Guan ◽  
Jingliang Xia ◽  
Jing Wang ◽  
Faguang Leng ◽  
Yongxiang Zhou ◽  
...  
Keyword(s):  
Blast Furnace ◽  
Portland Cement ◽  
Performance Enhancement ◽  
Cement Content ◽  
Free Water ◽  
Hydration Products ◽  
Cement Replacement ◽  
Replacement Method ◽  
Ferronickel Slag ◽  
White Portland Cement

Blast furnace ferronickel slag (BFFS) is generated in the production of ferronickel alloys and is used as cement replacement in concrete or mortar. The effectivity in reducing cement consumption and improving performance are limited. By referring to the paste replacement method, this work used BFFS to replace an equal volume of the white Portland cement paste to obtain greater performance enhancement. BFFS was used with five levels of replacement (0%, 5%, 10%, 15%, 20%) and four water-to-cement ratios (0.40, 0.45, 0.50, 0.55) were designed. Fluidity, mechanical strength, hydration products, and pore structure of every mixture were measured. The results showed that the workability of the mortars decreased due to the reduced volume of water, but the 28-day compressive strength of the mortars increased, and the cement content of the mortars was also reduced by 33 wt %. The X-ray diffraction (XRD) patterns revealed that there existed a carboaluminate phase, and the presence of the ettringite was stabilized, indicating that the accumulating amount of the hydration products of the mortar increased. Furthermore, the BFFS could consume the portlandite and free water to form a higher amount of chemically bound water due to its pozzolanic activity. A high degree of hydration and a large volume of the hydration products refined the porosity of the hardened mortars, which explained the enhancement of the strength of the mortars. Compared to the cement replacement method, the paste replacement method was more effective in preparing eco-friendly mortar or concrete by recycling BFFS for reducing the cement content of the mortar while improving its strength.

Mindful sport performance enhancement: Mental training for athletes and coaches.

2018 ◽  
Author(s):  
Keith A. Kaufman ◽  
Carol R. Glass ◽  
Timothy R. Pineau
Keyword(s):  
Performance Enhancement ◽  
Sport Performance ◽  
Mental Training

Performance Enhancement, Creativity and Mental Training

2003 ◽  
Author(s):  
M. Bar-Eli ◽  
O. Lowengart ◽  
J. Goldberg ◽  
S. Epstein ◽  
R. D. Fosbury
Keyword(s):  
Performance Enhancement ◽  
Mental Training

The Portland Cement Industry of the World

1898 ◽  
Vol 46 (1192supp) ◽  
pp. 19108-19109
Author(s):  
Bernard L. Green
Keyword(s):  
Portland Cement ◽  
Cement Industry ◽  
The World

Effective performance improvement of organic thin film transistors with multi-layer modifications

2020 ◽  
Vol 91 (3) ◽  
pp. 30201
Author(s):  
Hang Yu ◽  
Jianlin Zhou ◽  
Yuanyuan Hao ◽  
Yao Ni
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
Performance Enhancement ◽  
Organic Thin Film Transistors ◽  
Electrical Performance ◽  
Hole Injection ◽  
Organic Thin Film ◽  
Effective Performance ◽  
Significant Performance ◽  
P Type

Organic thin film transistors (OTFTs) based on dioctylbenzothienobenzothiophene (C8BTBT) and copper (Cu) electrodes were fabricated. For improving the electrical performance of the original devices, the different modifications were attempted to insert in three different positions including semiconductor/electrode interface, semiconductor bulk inside and semiconductor/insulator interface. In detail, 4,4′,4′′-tris[3-methylpheny(phenyl)amino] triphenylamine (m-MTDATA) was applied between C8BTBTand Cu electrodes as hole injection layer (HIL). Moreover, the fluorinated copper phthalo-cyanine (F16CuPc) was inserted in C8BTBT/SiO2 interface to form F16CuPc/C8BTBT heterojunction or C8BTBT bulk to form C8BTBT/F16CuPc/C8BTBT sandwich configuration. Our experiment shows that, the sandwich structured OTFTs have a significant performance enhancement when appropriate thickness modification is chosen, comparing with original C8BTBT devices. Then, even the low work function metal Cu was applied, a normal p-type operate-mode C8BTBT-OTFT with mobility as high as 2.56 cm2/Vs has been fabricated.

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