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Mechanical and Basic Physical Properties of High-Strength Concrete Exposed to Elevated Temperatures Lenka SCHEINHERROVÁ1,a *, Monika ČÁCHOVÁ1,b, Michaela PETŘÍKOVÁ1,c, Lukáš FIALA1,d, Eva VEJMELKOVÁ1,e, Stefania GRZESZCZYK2,f and Robert ČERNÝ1,g 1Czech Technical University in Prague, Faculty of Civil Engineering, Department of Materials Engineering and Chemistry, Thákurova 7, 166 29 Prague 6, Czech Republic 2Technical University of Opole, Faculty of Civil Engineering, Department of Engineering Building Materials, Katowicka 48, 45 061 Opole, Poland alenka.scheinherrova@fsv.cvut.cz, bmonika.cachova@fsv.cvut.cz, cmichaela.petrikova@fsv.cvut.cz, dfialal@fsv.cvut.cz, eeva.vejmelkova@fsv.cvut.cz, fs.grzeszczyk@po.opole.pl, gcernyr@fsv.cvut.cz Keywords: Mechanical properties, basic physical properties, high-strength concrete, elevated temperatures.
With these outstanding properties, high-strength concrete has been widely used in bridges, tunnels, nuclear power plants, or for marine and military structures [1-5].
The increasing trend of open porosity is a result of cracking of material structure and chemical changes undergoing in studied materials [16].
The changes in structure of samples were found and discussed.

Time duration in the steamer generated a solid matrix during developing the network structure.
Long duration in the steamer generated a solid matrix during the network structure development [2].
The compressive strength of steamed curing are greater than that of the normal curing, this condition also applied either for fibrous lightweight geopolymer binder or for lightweight geopolymer binder, which emphasize that the long duration in the steamer generated a solid matrix during the network structure development [2].
Rangan, “Development and Properties of Low-Calcium Fly Ash-Based Geopolymer Concrete”, in Research Report GC1, Perth, Australia: Faculty of Engineering, Curtin University of Technology. (2005) [4] J.Davidovits, Geopolymer Chemistry & Applications, 2nd edition, Publish by Institut Geopolymer 16 rue Galilee F-02100 Saint – Quentin, France. (2008) [5] S.E.

Application of Micro-suspended system in bleaching process of natural pigmented animal fiber Yan REN 1, a , Chengshu XU 2 , Jianwei XING 1 1Xi’an Polytechnic University, Xi’an, China 2 College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai,China ary901@163.com Keywords: Bleaching; Natual pigmented animal fiber; Micro-suspended System Abstract.
Introduction Either in the wool or in the special animal fibers, there contains a great deal of pigmented fiber, such as the brown cashmere which accounts for 60% of total production of cashmere[1], the fox cashmere which has a hollow structure and good performance in thermal insulation, and the camel hair etc.
However, agent A used in micro-suspended bleaching formed an oriented absorption on the surface of fiber, which is able to provide with a shield against the HO2－and OH－released from H2O2 and alkali respectively[6] to protect protein structure from the heat-moisture treatment.
[2] WeiguoChen, Lingqiang, Liu,Jianjian Wu, Study on structure and property of natural pigmented removed animal fibersal, journal of textile research, 32(2000),227-229

Anwar3,4,e 1Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia 2Department of Chemistry, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia 3Wood Finishing Laboratory, Forest Research Institute Malaysia (FRIM), 52109 Kepong, Selangor, Malaysia 4Institute of Tropical Forestry and Forest Products (INTROP), Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia amridhwanishak@yahoo.com, bzleman@eng.upm.edu.my, csapuan@eng.upm.edu.my, dmzaki@fsas.upm.edu.my, emkanwar@frim.gov.my Keywords: Sugar palm fibre, vacuum resin impregnation, impregnation time, Arenga pinnata Abstract.
It is well understood that natural fibres are hydrophilic in nature due to the presence of hydroxyl (OH) groups throughout its structure especially at cellulose and hemicellulose portions [3].
Frequent dimensional instability (fibre swelling in humid environment and shrinking in dry condition) would damage the composite interfacial bonding while biological attack would also damage fibre structure and decreases the composite mechanical properties [3].
The improvement can be explained that the impregnated resin did not only reduce water penetration into fibre cell wall but at the same time would also act to reinforce the fibre structure.

Further the as-coated Ni-P/-ZrO2 nanocoatings revealed mostly amorphous structures, while in heated coatings (temperatures 150, 350, and 550 0C with pure Ar) as temperature rises, the amorphous structure transformed leisurely to crystalline structure.
In Ni-P/-ZrO2 nanocomposite deposits, ZrO2 nanoparticles are well uniformly dispersed into the Ni-P matrix, and a globular nodule structure is seen.
The results showed that the NiP-ZrO2 nano composite coating exhibits a coarse nodular structure when compared to the mild steel substrate and NiP coating.
"Influence of heat treatment on crystal structure, microhardness and corrosion resistance of bilayer electroless Ni-P-SiC/Ni-P-Al2O3 Coatings."
Arabian Journal of Chemistry 16.9 (2023): 105028

CA models, first introduced by Von Neumann, have been successfully used in various fields including transportation, economics, and chemistry.
Post-earthquake Fire Risk Assessment Because the function, building structure and the ability of preventing fire vary in different urban areas, the post-earthquake fire risk also differs greatly.
(5) where Ai, j is a parameter representing the cell (i, j) in different risk classification region, Bi, j is a building structure parameter, Li, j represents the effect of different neighbors to the cell (i, j), Ei, j is a parameter that the building’s destruction by earthquake, and Wi, j is a parameter determined by the wind velocity and direction.
Some fire prevention measures (Fig. 4) were taken, e.g. widening road, changing building structure (from wooden or fire-prevention wooden to fireproof).

Synthesis, Characterization and Mechanism of Benzamide Intercalated Kaolinite by Replacement Method Hua Xia1,a, Shenghui Zhang2,b 1Faculty of Material Science and Chemistry, China University of Geosciences, Wuhan 430074, Hubei, P R China 2School of Material Science and Engineering, China University of Mining and Technology, Xuzhou 221008, Jiangsu, P R China aemail, caihua223@gmail.com ;bemail, shenghui_zhang @163.com Keywords: Kaolinite, Kaolinite/Benzamide intercalated complex, Melt intercalation Abstract.
In additional, Kaolinite is another candidate for a host material of nanocomposites because of its high crystallinity and high aspect ratio, which is a clay mineral with the 1:1-type layered structure consisting of an octahedral aluminum hydroxide sheet and a tetrahedral silica sheet.
It is possible, assuggested by Franco et al. [27], that the degree of order of the kaolinite/DMSO intercalated complex was destroyed and the disorder structure, probably consisting of random interstratification of both intercalated and non-intercalated kaolinite layers, was formed.
The result shows that the replacement can be divided into two stages: one is the deintercalation of partial DMSO molecules, which cause the formation of disordered structure, probably consisting of interstratification of intercalated and deintercalated layers.

Introduction Ordered mesoporous silica as an adsorbent offers a number of advantages including high specific surface area, large pore volume, regular channel type structures and adjustable pore size, as well as thermal and mechanical stability [1,2],. and contains a certain active silanols on the surface, which can react with organosilane reagents producing inorganic-organic hybrid mesoporous silica materials [3].
MCM-41 was synthesized using hydrothermal method[7], the source of silicon was TEOS, and the structure directing agent was CTAB.
This is because these mesoporous silica adsorbents have micron particles and pore structure are ordered, which are beneficial to the mass transfer of adsorbate in the pores.
Zheng: Environmental Toxicology and Chemistry Vol. 28 (2009), p. 1400 [7] Y.

Experiment Figure 1 shows a schematic illustration of the sample structure.
Schematic illustration of sample structure.
Phys, “Role of the Oxygen Molecule and of the Photogenerated Electron in TiO2-Photocatalyzed Air Oxidation Reactions,“The Journal of Physical Chemistry A, vol. 99, 1995, pp. 5633-5638
Gloss,” Effect of structure and morphology on photocatalytic properties of TiO2 layers,” Surface and Coatings Technology, vol. 202, 2008, pp. 2488-2493

Preparation of Fly Ash/rare Earth Adsorbent and Its Adsorption for Reactive Dye from Aqueous Solution Chen Wanga, Beigang Lib and Jing Mic Chemistry ＆ Environment Science College, Inner Mongolia Normal University, Hohhot 010022, China achensweet0929@qq.coma, blibg@imnu.edu.cnb, c574718043@qq.comc Keywords: Fly ash, La3+, Wool-used reactive red B, Adsorption properties.
FA has been utilized for the treatment research of various industry wastewater due to its large surface area, porous structure and with a great deal of active molecule such as Al2O3, SiO2.
It can be seen that La-FA adsorbent maintain the intrinsic crystal structure of FA and skeleton structure of FA had a certain change in the process of the lanthanum ions import, which can be relevant with the rise of adsorption amount of La-FA adsorbent.