跳至主要内容

Spray-Dry Agglomerated Nanoparticles in Ordinary Portland Cement Matrix

Read full paper at:
http://www.scirp.org/journal/PaperInformation.aspx?PaperID=50665#.VEh-HVfHRK0

Nano-sized particles have got a focus of great interest for the past decade. These ultrafine particles can have an effect in multiple ways on concrete technology. Although most of the effects of nanoparticles are desired, a huge surface area introduced by nanoparticles also incorporates negative effects, such as loss of workability and safety aspects. Agglomeration of nano-sized particles by spray-drying is one potential method to overcome the negative effects. In this study, ultra-fine material was dispersed and agglomerated successfully. Agglomerate structure was analyzed and performance was evaluated with mortar samples. Agglomerated nano-sized material had micron-sized inner porosity, which enabled water penetration into the agglomerates. In water exposure, agglomerates did not dissolve although some of binder glue and dispersing agent leaked out. Water penetration and organic material leaking enabled high reactivity and workability of the agglomerated nanoparticles. In spite of the high reactivity of agglomerated nanoparticles, slightly lower final compression strengths were observed with agglomerated ultrafine particles. The results of this study can be used in concrete technology when further developing admixture technologies and recipe designs. The negative side-effects of the agglomerated nanoparticles can be overcome and accounted for within application areas.
Cite this paper
Vehmas, T. , Kanerva, U. and Holt, E. (2014) Spray-Dry Agglomerated Nanoparticles in Ordinary Portland Cement Matrix. Materials Sciences and Applications, 5, 837-844. doi: 10.4236/msa.2014.512084
 

[1] Maynard, A.D. (2006) Nanotechnology: Assessing the Risks. Nano Today, 1, 22-33.
http://dx.doi.org/10.1016/S1748-0132(06)70045-7
[2] Maynard, A.D. (2007) Nanotechnology: The Next Big Thing, or Much Ado about Nothing? Annals of Occupational Hygiene, 51, 1-12.
http://dx.doi.org/10.1093/annhyg/mel071
[3] Sanchez, F. and Sobolev, K. (2010) Nanotechnology in Concrete—A Review. Construction and Building Materials, 24, 2060-2071.
http://dx.doi.org/10.1016/j.conbuildmat.2010.03.014
[4] Pacheco-Torgal, F. and Jalali, S. (2011) Nanotechnology: Advantages and Drawbacks in the Field of Construction and Building Materials. Construction and Building Materials, 25, 582-590.
http://dx.doi.org/10.1016/j.conbuildmat.2010.07.009
[5] Li, G.Y., Wang, P.M. and Zhao, X. (2005) Mechanical Behavior and Microstructure of Cement Composites Incorporating Surface-Treated Multi-Walled Carbon Nanotubes. Carbon, 43, 1239-1245.
http://dx.doi.org/10.1016/j.carbon.2004.12.017
[6] Li, G.Y., Wang, P.M. and Zhao, X. (2007) Pressure-Sensitive Properties and Microstructure of Carbon Nanotube Reinforced Cement Composites. Cement and Concrete Composites, 29, 377-382.
http://dx.doi.org/10.1016/j.cemconcomp.2006.12.011
[7] Ibusuki, T. and Takeuchi, K. (1994) Removal of Low Concentration Nitrogen Oxides through Photoassisted Heterogeneous Catalysis. Journal of Molecular Catalysis, 88, 93-102.
http://dx.doi.org/10.1016/0304-5102(93)E0247-E
[8] Ballari, M.M., Hunger, M., Hasken, G. and Brouwers, H.J.H. (2010) NOx Photocatalytic Degradation Employing Concrete Pavement Containing Titanium Dioxide. Applied Catalysis B: Environmental, 95, 245-254.
http://dx.doi.org/10.1016/j.apcatb.2010.01.002
[9] Sato, T. and Diallo, F. (2010) Seeding Effect of Nano-CaCO3 on the Hydration of Tricalcium Silicate. Journal of the Transportation Research Record, 2141, 61-67.
[10] Mondal, P., Shah, S., Marks, L. and Gaitero, J. (2010) Comparative Study of the Effects of Microsilica and Nanosilica in Concrete. Transportation Research Record, 2141, 6-9.
[11] Cassar, L. (2004) Photocatalysis of Cementitious Materials: Clean Buildings and Clean Air. MRS Bulletin, 5, 328-331.
http://dx.doi.org/10.1557/mrs2004.99
[12] Stark, J., Moser, B. and Bellmann, F. (2007) Nucleation and Growth of C-S-H Phases on Mineral Admixtures. Advances in Construction Materials, 531-538.
[13] Blyszko, J., Kiernozycki, W., Guskos, N., Zolnierkiewicz, G., Typek, J., Narkiewicz, U. and Podsiadly, M. (2008) Study of Mechanical Properties of Concrete with Low Concentration of Magnetic Nanoparticles. Journal of Non Crystalline Solids, 354, 4515-4518.
http://dx.doi.org/10.1016/j.jnoncrysol.2008.06.101
[14] Nazari, A. and Riahi, S. (2010) Assessment of the Effects of Fe2O3 Nanoparticles on Water Permeability, Workability, and Setting Time of Concrete. Journal of Composite Materials, 45, 923-930.
http://dx.doi.org/10.1177/0021998310377945
[15] Donaldson, K., Stone, V., Clouter, A., Renwick, L. and MacNee, W. (2001) Ultrafine Particles. Occupational and Environmental Medicine, 58, 211-216.
http://dx.doi.org/10.1136/oem.58.3.211
[16] Shaw, F. and Andrews, M. (1997) Spray Drying, Carbide, Nitride and Boride Materials Synthesis and Processing. Chapman & Hall, London.
[17] Harris, D.C. (2003) Quantitative Chemical Analysis. 6th Edition, W.H. Freeman and Company, New York.
[18] TCE1 (1997) Adiabatic and Semi-Adiabatic Calorimetry to Determine the Temperature Increase in Concrete Due to Hydration Heat of the Cement. Materials and Structures, 30, 451-464.
http://dx.doi.org/10.1007/BF02524773
[19] Darr, G.M. and Ludwig, U. (1973) Determination of Permeable Porosity. Materials and Structures, 6, 185.
[20] Rostasy, F.S., Weib, R. and Wiedemann, G. (1980) Changes of Pore Structure of Cement Mortar due Temperature. Cement and Concrete Research, 10, 157-164.
http://dx.doi.org/10.1016/0008-8846(80)90072-1
[21] Kumar, R. and Bhattacharjee, B. (2003) Porosity, Pore Size Distribution and In-Situ Strength of Concrete. Cement and concrete research, 33, 155-164.
http://dx.doi.org/10.1016/S0008-8846(02)00942-0.      eww141023lx

评论

此博客中的热门博文

Does Immigration Promote the Investment of the Monopolistic Firm?

In the present paper, we examine the effect of increasing uncertainty of immigrants’ growth on the optimal timing of investment of a firm that has a monopolistic power over the labor market. It is revealed that when the uncertainty of immigrants’ growth is more than a threshold level, increasing uncertainty of immigrants’ growth accelerates the optimal timing of firms’ investment and enhances the economic growth, even if the uncertainty of immigrants’ growth is formulated by the geometric Brownian motion, which is in sharp contrast to the standard result that an increase in the uncertainty postpones the optimal timing. With an increase in the immigrants over the past ten years, workforces in the host countries have been growing significantly to the extent that the immigrants represent 70% of the increase in the workforce in Europe, and 47% in the United States as OECD indicates. In the present paper, we attempted to investigate the effect of increased uncertainty caused by the growi...

Education Policy Implementation: A Mechanism for Enhancing Primary Education Development in Zanzibar

Education is one of the fundamental rights of individuals; therefore, the government of a country needs to develop and strengthen educational policy and quality as well as to ensure that everyone has equal access to basic education. The improvement of access and quality of education in the world is becoming as an essential factor in development, whereas the basic education (primary school), is acknowledged as a foundation of the higher educational development for every country. To fulfill this goal, governments introduce several policies and procedures; however, it requires some reforms and participation from the politician, policymakers, and other stakeholders to re-examine educational policy so that it can lead to multiplication and betterment of the reforms. Educational reforms actually focus on accountability. A positive educational development and reform is very challenging and needs more effort and strategy on how to use and utilize the resources effectively as such it can achie...