scholarly journals Low heat concrete hydration thermal reduction with bioconc

Author(s):  
M Basoeki ◽  
Koespiadi ◽  
J J Ekaputri
Author(s):  
Makno Basoeki ◽  
Koespiadi Koespiadi

This paper discuss the concrete hydration thermal control with the economical and eco-friendly Method Statement, based on the basic perfomance of concrete bio-admixture, Bioconc, which is produce mico-filler, reduce the binder content up to 40%.  The concrete hydration thermal sources is from the cement as binder, since Bioconc may reduce up to 40% binder content, the concrete hydration thermal can be controlled and worked as Low Heat Concrete.  The paper limited discuss about the application of the Bioconc,for laboratory scale trial mix, Low Heat Concrete mock up modelling test and comparison with another 2 (two) Low Heat Concrete above mentioned  [1] , [4]  and does not discuss the Bioconc ingredient. The research started by laboratory scale trial mix Fc'25 Low Heat Concrete Bioconc based concrete Job Mix, from cement content reduction 20%, 25%, 30% and 40%. The attached result shows optimum jobmix is Fc'25 Low Heat Concrete Bioconc based concrete Job Mix on 40% cement as binder content reduction, was choosen as Low Heat Concrete Mix Mock Up. Later on, further research make  mock up for sampling mass concrete dimension 1000x1000x2500 mm3 was executed. The attached Graph Thermal Monitoring Low Heat Concrete shows that the peak temperature occured 63,5 ?C in 29,5 hours after pouring  and maximum thermal differential between LHC layers is  19,5 ?C. Another two Low Heat Concrete Method Statement, i.e.: Pre-cooling and Low Heat Concrete with Fly Ash 40%, Mock Up Graph Thermal Monitoring also attached for comparison study. The observation and analysis proof that, “Low Heat Concrete Hydration Thermal Reduction with Bioconc”  is work simplifier and economically, for mass pouring.  The most essential thing is that, the basic concept of Bioconc’s Low Heat Concrete on reducing the mass concrete cement-binder content means reducing CO2  emision in every concrete production, without any hazard impact to the environment. Its mean Bioconc based Low Heat Concrete contribute to develop the green technology and eco-friendly technology on the concrete industry as sustainable green technology.


2019 ◽  
Vol 800 ◽  
pp. 379-391 ◽  
Author(s):  
P. Vázquez-Sánchez ◽  
M.A. Rodríguez-Escudero ◽  
F.J. Burgos ◽  
I. Llorente ◽  
O. Caballero-Calero ◽  
...  

2021 ◽  
Vol 154 (5) ◽  
pp. 054703
Author(s):  
Zhongpu Fang ◽  
Qi Wang ◽  
Yanli Li ◽  
Yi Li ◽  
Shuping Huang ◽  
...  

Chemistry ◽  
2021 ◽  
Vol 3 (1) ◽  
pp. 338-359
Author(s):  
Magdalena Bonarowska ◽  
Zbigniew Kaszkur ◽  
Krzysztof Matus ◽  
Alicja Drelinkiewicz ◽  
Tomasz Szumełda ◽  
...  

We present an efficient strategy for synthesising the PdAu catalysts with a homogeneous PdAu alloy phase for environmentally important hydrodechlorination of tetrachloromethane in the gas phase. The synthesis of carbon-supported catalysts involved two major steps: (i) incorporation of palladium and gold nanoparticles into carbon support and (ii) activation of the catalysts. The critical part of this work was to find the optimal conditions for both steps. Thus, the incorporation of the nanoparticles was carried out in two ways, by impregnation and direct redox reaction method using acetone solutions of metal precursor salts. The activation was performed either by a conventional thermal reduction in hydrogen or flash irradiation in a microwave oven. The homogeneity and structure of the PdAu alloy were found to depend on the catalyst activation method critically. In all cases, we observed better homogeneity for catalysts that were subject to microwave irradiation. Moreover, the flash microwave irradiation of prepared catalysts provided catalysts of better stability and selectivity towards the desired products (hydrocarbons) in the hydrodechlorination of tetrachloromethane as compared to the catalyst obtained by conventional thermal activation in hydrogen.


Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 744
Author(s):  
Christian Rodenbücher ◽  
Christo Guguschev ◽  
Carsten Korte ◽  
Sebastian Bette ◽  
Kristof Szot

In recent decades, the behavior of SrTiO3 upon annealing in reducing conditions has been under intense academic scrutiny. Classically, its conductivity can be described using point defect chemistry and predicting n-type or p-type semiconducting behavior depending on oxygen activity. In contrast, many examples of metallic behavior induced by thermal reduction have recently appeared in the literature, challenging this established understanding. In this study, we aim to resolve this contradiction by demonstrating that an initially insulating, as-received SrTiO3 single crystal can indeed be reduced to a metallic state, and is even stable against room temperature reoxidation. However, once the sample has been oxidized at a high temperature, subsequent reduction can no longer be used to induce metallic behavior, but semiconducting behavior in agreement with the predictions of point defect chemistry is observed. Our results indicate that the dislocation-rich surface layer plays a decisive role and that its local chemical composition can be changed depending on annealing conditions. This reveals that the prediction of the macroscopic electronic properties of SrTiO3 is a highly complex task, and not only the current temperature and oxygen activity but also the redox history play an important role.


2013 ◽  
Vol 22 (8) ◽  
pp. 085025 ◽  
Author(s):  
Qingzhao Kong ◽  
Shuang Hou ◽  
Qing Ji ◽  
Y L Mo ◽  
Gangbing Song

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 648
Author(s):  
Sanjeeb Lama ◽  
Jinuk Kim ◽  
Sivalingam Ramesh ◽  
Young-Jun Lee ◽  
Jihyun Kim ◽  
...  

Nanostructured materials synthesized by the hydrothermal and thermal reduction process were tested to detect the dimethyl methylphosphonate (DMMP) as a simulant for chemical warfare agents. Manganese oxide nitrogen-doped graphene oxide with polypyrrole (MnO2@NGO/PPy) exhibited the sensitivity of 51 Hz for 25 ppm of DMMP and showed the selectivity of 1.26 Hz/ppm. Nitrogen-doped multi-walled carbon nanotube (N-MWCNT) demonstrated good linearity with a correlation coefficient of 0.997. A comparison between a surface acoustic wave and quartz crystal microbalance sensor exhibited more than 100-times higher sensitivity of SAW sensor than QCM sensor.


Sign in / Sign up

Export Citation Format

Share Document