Influence of CNT Addition to the Frost Resistance of Concrete

2018 ◽  
Vol 760 ◽  
pp. 30-34
Author(s):  
Tomáš Jarolím ◽  
Jiří Brožovský ◽  
Dominik Šácha ◽  
Naděžda Pizúrová
Keyword(s):  
Frost Resistance ◽  
Materials Science ◽  
Climatic Conditions ◽  
Central European ◽  
University Of Technology

Frost resistance of concrete is one of the main durability parameter of Central European climatic conditions. Nanoparticles are the most worldwide examining in materials science. In Brno University of Technology has been interested in nanoparticles for years. First steps were dedicated in identification of nanoparticles (CNT), their dosage and dispersion. After solving before mentioned steps the CNT implementation to concrete could happened. In article was experimentally verify influence of CNT addition to concrete frost resistance after 100 frost cycles. Per results it could be said that addition small dosage of CNT increased frost resistance of concrete.

scholarly journals Moisture and Frost Resistance of the Recycled Base Rehabilitated with the Foamed Bitumen Technology / Odpornosc Na Oddziaływanie Wody I Mrozu Podbudowy W Technologii Recyklingu Z Asfaltem Spienionym

2012 ◽  
Vol 58 (2) ◽  
pp. 185-198 ◽  
Author(s):  
M. Iwanski ◽  
A. Chomicz-Kowalska
Keyword(s):  
Frost Resistance ◽  
New Technology ◽  
Physical And Mechanical Properties ◽  
Climatic Conditions ◽  
Specific Production ◽  
Central European ◽  
Road Pavement ◽  
Foamed Bitumen ◽  
Cold Recycling ◽  
Production Conditions

Abstract The technology of recycling with foamed bitumen is a new technology of road rehabilitation. Due to the climatic conditions in the Central European countries, road pavement structure should be moisture and frost resistant. Because of its specific production conditions, this is especially important for pavements rehabilitation with the cold recycling technology. Determining the physical and mechanical properties, as well as moisture and frost resistance, depends on binder and filler contents. They are the key elements before its use for road building. The tests presented here have been performed on mineral recycled base mixes with foamed bitumen. The material from the existing layers was used. The content of bitumen binder amounted to 2.0%, 2.5%, 3.0% and 3.5%, while that of cement to 1.0%, 1.5%, 2.0%, 2.5%. The results were subject to the optimization process. This allowed to state that with the use of 2.5% foamed bitumen and 2.0% of cement, the base had the required properties, as well as the moisture and frost resistance.

scholarly journals Concrete based on sulfur binder being modified with inorganic additives

2018 ◽  
Vol 212 ◽  
pp. 01013
Author(s):  
Vadim Balabanov ◽  
Victor Baryshok ◽  
Nikita Epishkin
Keyword(s):  
Frost Resistance ◽  
Building Materials ◽  
Physical And Mechanical Properties ◽  
High Strength ◽  
Strength Properties ◽  
Climatic Conditions ◽  
Freezing And Thawing ◽  
Concrete Mixtures ◽  
Irkutsk Region ◽  
Water Saturated

The sharply continental climate of the Irkutsk region is characterized by wide temperature intervals throughout the year. The repeated cyclicity of freezing and thawing of building materials in the water-saturated state influences the change in technical characteristics and the durability of concrete products and structures. The concrete products’ features in such climatic conditions create the need for the production of concretes with improved indicators of physical and mechanical properties. The effect of modifying additives on the technological characteristics of sulfur concrete is established. The effect of all elements of sulfur concrete on its strength and frost resistance. The composition of sulfuric concrete is obtained, which meets all the requirements and also has high strength and increased frost resistance. Formulations with a certain ratio of structural sulfuric concrete mixtures were developed. As a result of the use of technical sulfur in the composition of concrete products, the problem of utilizing annually accumulating reserves of technical sulfur is partially solved. The strength properties of sulfuric concretes easily compete with high-quality brands of concrete, special types of concretes that have in their composition additives.

scholarly journals Introduction

2003 ◽  
Vol 9 (4) ◽  
pp. 336-336
Author(s):  
Michal Zelechower ◽  
Pawel Zieba ◽  
Clive Walker
Keyword(s):  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Materials Science ◽  
Polish Academy ◽  
Science Institute ◽  
Materials Engineering ◽  
University Of Technology ◽  
Regional Workshop ◽  
Analysis Society ◽  
Microbeam Analysis Society

This issue of Microscopy and Microanalysis contains selected papers from the fifth Regional Workshop of the European Microbeam Analysis Society (EMAS) on Electron Probe Microanalysis—Practical Aspects that took place May 22–25, 2002 at Szczyrk, Poland. The meeting was organized by the Polish National Branch of EMAS in collaboration with the Silesian University of Technology (Faculty of Materials Engineering and Metallurgy) and the Polish Academy of Science (Institute of Metallurgy and Materials Science).

scholarly journals Sweet Basil (Ocimum basilicum L.) Productivity and Raw Material Quality from Organic Cultivation

Agronomy ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 279 ◽  
Author(s):  
Katarzyna Bączek ◽  
Olga Kosakowska ◽  
Małgorzata Gniewosz ◽  
Iwona Gientka ◽  
Zenon Węglarz
Keyword(s):  
Essential Oil ◽  
Open Field ◽  
Microbiological Quality ◽  
Farming System ◽  
Climatic Conditions ◽  
Raw Material ◽  
Conventional Agriculture ◽  
Central European ◽  
Sweet Basil ◽  
Organic Cultivation

Sweet basil is one of the most important culinary herbs. Currently, its production is carried out mainly in accordance with conventional agriculture. However, its cultivation in organic systems seems to be better adjusted to consumer demands connected with the lack of pesticide residues in foods and their safety. In the present study, two methods of basil cultivation in organic farming system were applied, i.e., in the open air and under foil tunnels. During the experiment, in central European climatic conditions, it was possible to obtain four successive cuts of herb. The herb was subjected to chemical analysis, including determination of the content of essential oil, phenolic compounds, and chlorophylls. Gas chromatography coupled with mass spectrometry (GC–MS) and flame ionization detector (GC-FID) analysis of the essential oil was performed, whereas the fresh herb was subjected to sensory analysis. The cumulative mass of fresh herb was distinctly higher in the cultivation under foil tunnels (44.7 kg∙10 m−2) in comparison to the open field (24.7 kg∙10 m−2). The content of essential oil, flavonoids, and phenolic acids was also higher in the raw material collected from plants grown under foil tunnels (0.81, 0.36, and 0.78 g·100g−1 DW, respectively) than from the open field (0.48, 0.29, and 0.59g·100g−1 DW, respectively). In turn, the dominant compound of the essential oil, i.e., linalool, was present in higher amounts in the essential oil obtained from plants cultivated in the open field. The sensory and microbiological quality of herb was comparable for both methods of cultivation. The obtained results indicate that, in central European climatic conditions, it is possible to obtain good-quality yield of basil herb. However, for its better productivity, it seems that cultivation under foil tunnels is preferable.

scholarly journals Effect of different agronomical measures on yield and quality of autumn saved herbage during winter grazing – 2nd communication: Crude protein, energy and ergosterol concentration

2011 ◽  
Vol 51 (No. 6) ◽  
pp. 271-277 ◽  
Author(s):  
W. OPITZ VON BOBERFELD ◽  
K. BANZHAF ◽  
F. HRABE ◽  
J. SKLADANKA ◽  
S. KOZLOWSKI ◽  
...  
Keyword(s):  
Crude Protein ◽  
Dry Matter ◽  
Climatic Conditions ◽  
The Czech Republic ◽  
Central European ◽  
Yield And Quality ◽  
Protein Energy ◽  
Winter Grazing ◽  
Adequate Quantity

In addition to the results published in the first communication (Opitz von Boberfeld et al., 2006) this paper presents crude protein, energy (ME) and ergosterol concentrations of autumn saved herbage at different sites in Central Germany, Poland, Hungary and the Czech Republic. Within these sites, the influence of the factors pre-utilisation and winter harvest date was tested over three consecutive years. Related to the different climatic conditions of the sites, crude protein concentrations of the growths pre-utilised in July varied from 149 g/kg in November to 134 g/kg of dry matter (DM) in January. The influence of climatic conditions was different on each location and varied depending on the year. Generally, the consistent effect of the factor “site” related to altitude could not be observed. While the energy concentrations decreased with advancing winter and partly reached the values below 6 MJ ME/kg of DM in January, the ergosterol concentrations increased. The results demonstrate that under Central European conditions autumn saved herbage, pre-utilised in July, could provide adequate quantity and quality for suckler cows until December. Afterwards, the utilisation of preserved forages becomes essential.  

scholarly journals Hot summers, long life: egg laying strategies of Maniola butterflies are affected by geographic provenance rather than adult diet

2013 ◽  
Vol 82 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Andrea Grill ◽  
Andrea Cerny ◽  
Konrad Fiedler
Keyword(s):  
Amino Acids ◽  
Egg Production ◽  
Sucrose Solution ◽  
Reproductive Period ◽  
Climatic Conditions ◽  
Egg Laying ◽  
Endogenous Factors ◽  
Central European ◽  
Oviposition Strategy ◽  
Adult Diet

Maniola butterflies undergo summer dormancy in dry and hot habitats and deposit their eggs only in early autumn when conditions become more favourable for their offspring. Female individuals of this genus are therefore relatively long-lived. For long-lived butterflies adult diet is of particular importance. We tested if added amino acids in nectar substitute fed to the butterflies affected timing of oviposition, fecundity and longevity. A hundred Maniola females were sampled from Mediterranean and Central European populations and made to oviposit under controlled laboratory conditions. Forty individuals were offered sucrose solution with additional amino acids while the remainder were fed with plain sucrose solution. We found that egg-laying strategies and longevity depended on geographic provenance rather than diet. Supplementary amino acids in adult diet did neither prolong lifetime nor increase total egg production. Maniola females from Sardinia started to lay eggs at least 20 days later relative to Central European M. jurtina and lived three times as long. Mediterranean individuals had on average twice the length of reproductive period and lifespan relative to Central European ones, and individuals of Pannonian origin lived longer than Alpine butterflies. Average total egg numbers were 200-350 eggs per female and did not differ significantly between populations. The fact that oviposition strategy could not be altered through diet may indicate that for univoltine butterflies, like Maniola, diet-quality at the adult stage is less important than endogenous factors, or factors the butterflies are exposed to in an earlier developmental stage than the imago. Oviposition strategy closely matched the climatic conditions that prevail in the geographic regions where these butterflies fly.

John Robert Anderson 1928–2007

2014 ◽  
Vol 25 (2) ◽  
pp. 253
Author(s):  
Neil R. Avery ◽  
W. Roy Jackson ◽  
Thomas H. Spurling
Keyword(s):  
Technical College ◽  
Materials Science ◽  
New South ◽  
New South Wales ◽  
South Australia ◽  
University Of Cambridge ◽  
South Wales ◽  
University Of Technology ◽  
The University ◽  
Csiro Division

John Anderson was born in Sydney on 5 March 1928 and died in Melbourne on 26 February 2007. He was educated at Sydney Boys' High School, Sydney Technical College, the New South Wales University of Technology (now the University of New South Wales) and the University of Cambridge. He was at Queens University Belfast as a Ramsay Memorial Fellow, 1954–5, was a Lecturer in Chemistry at the New South Wales University of Technology, a Reader in Chemistry at the University of Melbourne and Foundation Professor of Chemistry at Flinders University in South Australia. In 1969 he was appointed Chief of the CSIRO Division of Tribophysics and managed the Division's transition to become the Division of Materials Science. He was a Professor of Chemistry at Monash University, Melbourne, from 1987 until his retirement in 1993. He will be remembered for his contributions to the understanding of gas–solid interactions with particular emphasis on fundamental heterogeneous catalysis on metals, but also embracing other adsorption and oxidation processes.

Extensive Roof Green in Central European Climate

2016 ◽  
Vol 824 ◽  
pp. 795-802
Author(s):  
Miroslav Kravka ◽  
Martin Daněk ◽  
Roman Rabenseifer
Keyword(s):  
Extreme Temperature ◽  
Climatic Conditions ◽  
Natural Substrate ◽  
Positive Health ◽  
Temperature Variations ◽  
Central European ◽  
European Area ◽  
European Climate ◽  
Four Seasons ◽  
Selection Of

The essence of the green roof is vegetation and its positive health and aesthetic effects on humans. They can, however, only be achieved, if the vegetation is really functional. In climatic conditions of Central Europe with four seasons of the same length, approximately, with cold winters and relatively warm, and often dry, summers are plants in artificial conditions, for which the vegetation of the roof can be considered, subject to extreme temperature variations. Even plants typical for central European area that thrive in this environment can be difficult to survive. In contrast to the plants rooted in the usual field, the temperature of which oscillates during the year at a depth of one meter under the surface between 0° and approx. 16° Celsius, i.e. in the range of approx. 16 Kelvin, the roots of vegetation planted on roofs are exposed to a much wider temperature range. The study to be presented describes an example of a typical roof with extensive greenery and shows the temperature course in substrate of the roof vegetation during a typical winter and summer day and compares it to the temperature course at the same depth below the field surface. It also provides methods that can solve this problem, from the selection of suitable plant species through year-round care, e.g. using summer irrigation and winter protection, up to artificial creation of a constant temperature of natural substrate with heated / cooled ceilings under the roof.

scholarly journals Energy Storage Requirements for PV Power Ramp Rate Control in Northern Europe

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Julius Schnabel ◽  
Seppo Valkealahti
Keyword(s):  
Energy Storage ◽  
Control Strategy ◽  
Storage Systems ◽  
Primary Energy ◽  
Climatic Conditions ◽  
Solar Pv ◽  
Energy Storage Systems ◽  
Ramp Rate ◽  
Performance Requirements ◽  
University Of Technology

Photovoltaic (PV) generators suffer from fluctuating output power due to the highly fluctuating primary energy source. With significant PV penetration, these fluctuations can lead to power system instability and power quality problems. The use of energy storage systems as fluctuation compensators has been proposed as means to mitigate these problems. In this paper, the behavior of PV power fluctuations in Northern European climatic conditions and requirements for sizing the energy storage systems to compensate them have been investigated and compared to similar studies done in Southern European climate. These investigations have been performed through simulations that utilize measurements from the Tampere University of Technology solar PV power station research plant in Finland. An enhanced energy storage charging control strategy has been developed and tested. Energy storage capacity, power, and cycling requirements have been derived for different PV generator sizes and power ramp rate requirements. The developed control strategy leads to lesser performance requirements for the energy storage systems compared to the methods presented earlier. Further, some differences on the operation of PV generators in Northern and Southern European climates have been detected.

Sign in / Sign up

Export Citation Format

Share Document