scholarly journals A study on micro-morphology and impacts of curing temperature on bond strength of interfacial transition zone through scanning electron microscope

2021 ◽  
Vol 2083 (2) ◽  
pp. 022082
Author(s):  
Binbin Na ◽  
Bin Yan
Keyword(s):  
Electron Microscopy ◽  
Bond Strength ◽  
Interfacial Transition Zone ◽  
Curing Temperature ◽  
Early Age ◽  
Hydration Products ◽  
Growth Trend ◽  
Micro Morphology ◽  
Morphology Characteristics ◽  
Scanning Electron

Abstract The influence of curing temperature on the bond strength of ITZ was studied in this paper. It is found that, Increasing curing temperature can improve the bond strength of ITZ in the early age, but it will significantly decreases the growth trend of the bond strength. The micro-morphology characteristics were examined by the method of scanning electron microscopy, It was found that, the higher the curing temperature is, the more uneven the hydration products distribution of ITZ is, and also the looser the ITZ structure is.

An Investigation on the Interfacial Transition Zone in Concrete Using SEM

2012 ◽  
Vol 446-449 ◽  
pp. 166-170
Author(s):  
Hsi Chi Yang ◽  
Miao Ying Cheng ◽  
Jung Pin Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transition Zone ◽  
Calcium Ion ◽  
Test Specimen ◽  
Interfacial Transition Zone ◽  
Small Samples ◽  
Hydration Products ◽  
Compressive Test ◽  
Scanning Electron

The technique of linking the SEM (Scanning Electron Microscopy) photographs taken around the interfacial transition zone area is applied to observe the development of hydration products for aggregate and paste at the different curing ages. This research first chooses the aggregate with clay properties not containing the calcium ion, and then observes the hydration products (such as CH, C-S-H) of calcium ion on the aggregate. Finally it assesses if the aggregate will produce ion exchange with cement and generate the hydration products. The very small samples to be observed are taken from the concrete compressive test specimen and must include both aggregate and paste. They are wiped with alcohol to have better pictures before shooting SEM. Initially, the interface of aggregate and paste is sought using 2000x magnification. However, the hydration products on either side of the interface with a range of 50 μm are observed using 10000x magnification. From the results, it is found that aggregate has not interacted with cement paste to produce hydration products and the bond stress of aggregate and paste is controlled by hydration products of paste.

scholarly journals First definitive record of a whip scorpion Labochirus tauricornis (Pocock, 1900) from Goa, India: with notes on its morphometry and pedipalp micro-morphology

2018 ◽  
Vol 10 (7) ◽  
pp. 11955
Author(s):  
Manoj Ramakant Borkar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sexual Dimorphism ◽  
Diagnostic Value ◽  
The State ◽  
Diagnostic Data ◽  
Micro Morphology ◽  
Scanning Electron

Bastawade & Borkar in 2008 made a passing reference to the presence of a single uropygid species in Goa, though without much primary diagnostic data on the collected specimen of four females.  The present study puts in place a definitive record of the uropygid, Labochirus tauricornis Pocock, (1900) in the state of Goa, and addresses an important gap in our understanding of its occurrence, morphology, and ecology. Besides documenting the species of this cryptozoic, nocturnal arachnid predator commonly known as ‘Vinegaroon’ on account of their vinegary allomone spray; the present study also describes the gross morphology , morphometry and micro-morphology of non-ambulatory sub-raptorial pedipalps which are of taxonomic-diagnostic value, elucidated using scanning electron microscopy, in addition to routine stereomicroscopy. The paper also examines in detail, sexual dimorphism and morphometry of this uropygid species. 

Influence of Cementitious Capillary Crystalline Waterproofing Material on the Water Impermeability and Microstructure of Concrete

2019 ◽  
Vol 953 ◽  
pp. 209-214
Author(s):  
Yi Teng Zhang ◽  
Lian Zuo ◽  
Jin Chao Yang ◽  
Wei Xia Zhao ◽  
Xiang Xiong Zeng
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Differential Scanning Calorimetry ◽  
Cement Matrix ◽  
Hardened Cement ◽  
Hydration Products ◽  
Hardened Cement Paste ◽  
Scanning Calorimetry ◽  
Chinese Standard ◽  
Scanning Electron

The main objective of this study is to investigate the effect of cementitious capillary crystalline waterproofing (CCCW) material on the water impermeability and microstructure of concrete. The water impermeability of concrete covered with or without CCCW material was tested according to the Chinese standard GB 18445-2012. The results indicate that concretes coated with CCCW material showed much higher water impermeability than blank ones, and the ratio of water impermeability pressure between them reached 275. The samples obtained in various depths of hardened cement paste specimens with or without CCCW coating were analyzed through scanning electron microscopy (SEM) and thermogravimetry-differential scanning calorimetry (TG-DSC), to study the differences in microstructure and hydration products. The results present that after a 28-day standard curing, there were lots of ettringite crystals and CaCO3 formed in the paste in 1 cm from the coating, but the action depth of the CCCW coating could not reach 3 cm. The ettringite and CaCO3 is precipitated in the pore structure of cement matrix and filling the voids, which leads to the significant enhancement in water impermeability.

Scanning Electron Microscopy in the Studies of Hydrated Cementitious Materials Microstructure Formed in the Presence of some Heavy Metals Containing Admixtures

2015 ◽  
Vol 231 ◽  
pp. 145-153 ◽  
Author(s):  
Wiesława Nocuń-Wczelik ◽  
Barbara Trybalska
Keyword(s):  
Electron Microscopy ◽  
Cement Hydration ◽  
Cementitious Materials ◽  
Early Age ◽  
Silicate Phase ◽  
Small Individual ◽  
Calorimetric Measurements ◽  
Individual Particles ◽  
Scanning Electron ◽  
Nitrate Solutions

The calorimetric measurements together with microscopic observations and analyses relating to the interaction of cement paste with sulfate and nitrate solutions of various concentration were carried out. These salts modify the rate of cement hydration at early age. In the presence of sulfates the formation of some well crystallized calcium sulfates or calcium sulfoaluminates can be found. In case of nitrates there is no additional products. However, one can observe that the calcium silicate phase becomes less fibrous but more compact, with very small individual particles, as the nucleation from the liquid phase is disturbed. There are the accompanying cations incorporated in this product.

Fabrication of TiAl/Ti2AlC Composite by Reaction Hot Pressing

2011 ◽  
Vol 52-54 ◽  
pp. 842-845 ◽  
Author(s):  
Jian Feng Zhu ◽  
Wen Wen Yang ◽  
Yi Ping Gong
Keyword(s):  
Electron Microscopy ◽  
Reaction Process ◽  
Hot Press ◽  
X Ray Diffraction ◽  
X Ray ◽  
In Situ Composite ◽  
The Matrix ◽  
Morphology Characteristics ◽  
Scanning Electron

TiAl/Ti2AlC in situ composite was successfully fabricated by hot-press-assisted reaction process from the mixture of Ti, Al and carbon black. The phase formation and transformation were investigated in detail by X-ray diffraction (XRD) and the morphology characteristics were also studied by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results show that when the mixed powders were hot pressed at 1300 °C for 1 h, full dense and highly pure TiAl/Ti2AlC composite was synthesized. The TiAl was the matrix phase and the in situ synthesized Ti2AlC was reinforcing phase. The reaction process was also discussed.

Differential Resin-Dentin Bonds Created after Caries Removal with Polymer Burs

2012 ◽  
Vol 18 (3) ◽  
pp. 497-508 ◽  
Author(s):  
Manuel Toledano ◽  
Inmaculada Cabello ◽  
Monica Yamauti ◽  
Raquel Osorio
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Bond Strength ◽  
Measured Data ◽  
Glass Ionomer ◽  
Single Bond ◽  
Microtensile Bond Strength ◽  
Caries Removal ◽  
Thick Smear ◽  
Scanning Electron

AbstractThe objective of this article was to investigate the effect of carbide and polymer burs caries removal methods on the bond strength of different adhesives to dentin. Resin restorations were performed in sound and caries-affected dentin, after using polymer or carbide burs and bonding with four different adhesive (Single bond, SB; Clearfil SE bond, SEB; FL-Bond II, FLB; and Fuji II-LC, FUJI). Microtensile bond strength (MTBS) was measured. Data were analyzed with ANOVA and Student-Newman-Keuls tests. Debonded surfaces were observed by scanning electron microscopy. Bonded interfaces were examined using light microscopy (Masson's trichrome staining). In sound dentin, MTBS was similar for SEB and SB, and higher than that of FLB and FUJI. Bond strength to carbide bur prepared dentin was similar for SB, SEB, and FLB; FUJI presented the lowest. SB applied on polymer bur excavated dentin presented similar values to those of the carbide bur group; MTBS attained by SEB, FLB, and FUJI decreased when bonding to dentin treated with polymer burs; FUJI yielded pretesting failures in all specimens. Polymer burs created a thick smear layer that was not infiltrated by tested self-etching agents. The bonding effectiveness of self-etching and glass-ionomer-like adhesives to dentin decreased when polymer burs were used.

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