Modifying Stucco Mortars with Additions of Sulphoaluminate Cement and Aluminate Cement

2018 ◽  
Vol 276 ◽  
pp. 198-203 ◽  
Author(s):  
Wacław Brachaczek

Stucco products due to the specific nature should be characterized by a short time of the beginning and end of setting, low shrinkage, good adhesion to the substrates and workability at running. The type of cement used has a significant influence on this parameter. The change in the physical properties of stucco mortars in which Portland cement was gradually replaced with AliCem sulphoaluminate cement and Górkal 70 aluminate cement. For this purpose, two sets of samples were prepared, in the first set the percentage of Górkal 70 cement in relation to the entire cement was 15, 20, 25, 30 and 33%, in the second set the percentage of Alicem cement was 25, 50, 75 and 100%. The research results indicate that both cements significantly shortened the setting time of the mortars, reduced the shrinkage and improved adhesion to the substrates.

Alloy Digest ◽  
1966 ◽  
Vol 15 (11) ◽  

Abstract Ti-679 is a titanium high temperature alloy having an excellent combination of short-time strength, creep strength and stability to 900 F. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ti-48. Producer or source: Titanium Metals Corporation of America.


2019 ◽  
Vol 7 (2) ◽  
Author(s):  
Widodo Widodo ◽  
Marshelly Chandra Kumala

<em>The objective of this is research was conducted to find out how the influence of the price and quality of products against customer loyalty at PT. Alakasa Extrusindo Jakarta. This research was conducted in Alakasa Extrusindo PT by doing data collection, through the primary data and secondary data.  The research results showed that the simultaneous price variables  and product quality  has a positive and significant effect against the variable customer loyalty. partially showed that price variables has a positive and significant influence towards customer loyalty. And partially showed that product quality variables  has a positive and significant influence towards customer loyalty</em>


Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 731
Author(s):  
Chunlong Huang ◽  
Zirui Cheng ◽  
Jihui Zhao ◽  
Yiren Wang ◽  
Jie Pang

The ferrite aluminate cement (FAC) could rapidly lose fluidity or workability due to its excessive hydration rate, and greatly reduce the construction performance. Chemical admixtures are commonly used to provide the workability of cement-based materials. In this study, to ensure required fluidity of FAC, chemically different water reducing agents are incorporated into the FAC pastes. The experiments are performed with aliphatic water reducing agent (AP), polycarboxylic acid water reducing agent (PC) and melamine water reducing agent (MA), respectively. Influence of the water reducing agents on fluidity, setting time, hydration process, hydration product and zeta potential of the fresh cement pastes is investigated. The results show that PC has a better dispersion capacity compared to AP and MA. Besides decreasing water dosage, PC also acts as a retarder, significantly increasing the setting times, delaying the hydration rate and leading to less ettringite in the hydration process of FAC particles. The water reducing agents molecules are adsorbed on the surface of positively charged minerals and hydration products, however, for PC, steric hindrance from the long side chain of PC plays a critical role in dispersing cement particles, whereas AP and MA acting through an electrostatic repulsion force.


Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 728
Author(s):  
David Donnermeyer ◽  
Magdalena Ibing ◽  
Sebastian Bürklein ◽  
Iris Weber ◽  
Maximilian P. Reitze ◽  
...  

The aim of this study was to gain information about the effect of thermal treatment of calcium silicate-based sealers. BioRoot RCS (BR), Total Fill BC Sealer (TFBC), and Total Fill BC Sealer HiFlow (TFHF) were exposed to thermal treatment at 37 °C, 47 °C, 57 °C, 67 °C, 77 °C, 87 °C and 97 °C for 30 s. Heat treatment at 97 °C was performed for 60 and 180 s to simulate inappropriate application of warm obturation techniques. Thereafter, specimens were cooled to 37 °C and physical properties (setting time/flow/film thickness according to ISO 6876) were evaluated. Chemical properties (Fourier-transform infrared spectroscopy) were assessed after incubation of the specimens in an incubator at 37 °C and 100% humidity for 8 weeks. Statistical analysis of physical properties was performed using the Kruskal-Wallis-Test (P = 0.05). The setting time, flow, and film thickness of TFBC and TFHF were not relevantly influenced by thermal treatment. Setting time of BR decreased slightly when temperature of heat application increased from 37 °C to 77 °C (P < 0.05). Further heat treatment of BR above 77 °C led to an immediate setting. FT-IR spectroscopy did not reveal any chemical changes for either sealers. Thermal treatment did not lead to any substantial chemical changes at all temperature levels, while physical properties of BR were compromised by heating. TFBC and TFHF can be considered suitable for warm obturation techniques.


Metals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1400
Author(s):  
Peter Baumli

The paper reviews the preparation of the different metallic nanocomposites. In the preparation of composites, especially in the case of nanocomposites, interfacial phenomena play an important role. This review summarizes the literature on various interfacial phenomena, such as wettability and reactivity in the case of casting techniques and colloidal behavior in the case of electrochemical and electroless methods. The main contribution of this work lies in the evaluation of collected interfacial phenomena and difficulties in the production of metal matrix composites, for both nano-sized and micro-sized reinforcements. This study can guide the composite maker in choosing the best criteria for producing metal matrix composites, which means a real interface with good adhesion between the matrix and the reinforcement. This criterion results in desirable mechanical and physical properties and homogenous dispersion of the reinforcement in the matrix.


2021 ◽  
Vol 8 (8) ◽  
pp. 55-63
Author(s):  
Deby Yurika Lasmarito Siahaan ◽  
Rina Br Bukit ◽  
Tarmizi .

The research objective was to examine and analyze whether Profitability, Asset Structure, Firm Size simultaneously and partially influenced Stock Returns in Manufacturing Companies. In addition, this study also tries to prove whether Corporate Governance can be used as a moderator in the research model. The research results showed that simultaneously Profitability, Asset Structure, Firm Size significantly influenced Stock Returns. Partially, profitability has a positive and significant influence on Stock Returns. Asset Structure has a positive and significant influence on Stock Returns, and Company size has a positive and insignificant influence on Stock Returns. The variable of Corporate Governance can moderate the influence of Asset Structure on Stock Returns. However, Corporate Governance will not be able to moderate the influence of Profitability on Stock Returns. Keywords: Profitability, Asset Structure, Firm Size, Stock Return, and Corporate Governance.


Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2417 ◽  
Author(s):  
Mingxu Chen ◽  
Xiangyang Guo ◽  
Yan Zheng ◽  
Laibo Li ◽  
Zhen Yan ◽  
...  

Rapid setting and low viscosity of sulphoaluminate cement (SAC) make it difficult to be extruded by 3D printing (3DP) technique. In this study, the effect of tartaric acid (TA) on printability, rheology and mechanical property of 3DP SAC paste is investigated. The experimental results indicate that the setting time, hydration evolution and apparent viscosity of SAC paste can be well controlled by adding a proper amount of TA to satisfy the requirements of 3DP. An excellent structure of SAC paste with the ultimate deformation rate less than 10% can be printed without compromising mechanical strength.


Sign in / Sign up

Export Citation Format

Share Document