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Vanillic and Meldrum’s Acid Containing Antioxidant Laima Bērziņa1,a and Inese Mieriņa1,b* 1Institute of Technology of Organic Chemistry, Faculty of Materials Science and Applied Chemistry, Riga Technical University, Riga, Latvia aLaima.Berzina_1@rtu.lv, bInese.Mierina@rtu.lv Keywords: Antioxidant, antiradical activity, Meldrum’s acid, vanillic acid.
The structures of the previously studied antioxidants It is worth mentioning that vanillin and vanillic acid are valuable nature-derived molecules containing the substituents reasonable for antiradical activity.
General structure of the target compounds Results and discussion Synthesis of the target compounds The retrosynthetic analysis (Scheme 1) of the target compounds 5 foreseen both linear and convergent strategies.
Firstly, we observed insufficient solubility of compound 13 in some of the reaction conditions for the Knoevenagel condensation with Meldrum’s acid (15), which was successful for other similar structures.

It was found that the final strength of iron ore pellets is in accordance with the structure of the pellets and the value of internal stresses.
The structure and stress acting in the pellets depend on the high-temperature hardening mode.
The reason for the decrease in the strength of the pellets cooled at a high rate is the occurrence of internal stresses caused by a change in the structure, as evidenced by the change in the pellets porosity [25].
Dli, Computer modeling of the chemical-power engineering process of roasting of a moving multilayer mass of phosphorite pellets, Doklady Chemistry. 477(2) (2017) 282-285
Dli, Computer-aided modeling of the chemical process of drying of a moving dense multilayer mass of phosphorite pellets, Doklady Chemistry. 475(2) (2017) 188-191

KOH, ZnCl2, H3PO4, NaOH, H2SO4) was mixed with char for developing pore structure.
N2, CO2, and vapor) or steam at high temperatures for developing carbon pores structure [10].
This functional group is an element of the structure of activated carbon [17].
Concentration variation of potassium hydroxide affects the pore structure and pore size of activated carbon.
Ismadji, Activated carbon from jackfruit peel waste by H3PO4 chemical activation: pore structure and surface chemistry characterization, Chem.

Jovanovićd Institute of Chemistry Technology and Metallurgy, Department of Catalysis and Chemical Engineering, Njegoševa 12, 11000 Belgrade, Serbia and Montenegro a zvukovic@nanosys.ihtm.bg.ac.yu, bsnikolic@nanosys.ihtm.bg.ac.yu, c jkrstic@nanosys.ihtm.bg.ac.yu, ddusanmj@nanosys.ihtm.bg.ac.yu Keywords: Acid Activation, Bentonite, Nanostructure, Textural Properties.
Further increase in acid concentration does not result in development of new porous structure.
During acid treatment of bentonite, exchangeable cations (K +, Na + and Ca 2+) are replaced with H + in the interlamellar space while part of Al 3+, Fe 3+ and Mg 2+ ions are leached from the octahedral sheets of the lattice structure [1, 2].
At certain point the formed amorphous structure protects unaltered or partially altered bentonite particles from further acid attack and development of porous structure [5].
Further increase in acid concentration does not result in development of new porous structure.

X-ray diffraction studies revealed that the deposited films are found to be hexagonal structure with preferential orientation along (002) plane.
CdSe thin films are usually crystallized in hexagonal (wurtzite) structure [4], and in the cubic (zinc blende) structure [6].
Most of the research reports on CdSe thin films dealt with the determination of structure type and qualitative observation of defects and grain size for CdSe thin films.
Xray diffraction studies revealed that the deposited films of CdSe are found to be polycrystalline in nature with hexagonal structure with lattice constants (a=4.299Å; c=7.010 Å).
T.Mahalingam, S.Thanikaikarasan, R.Chandramohan, M.Raja, C.Sanjeeviraja, Jong- Ho Kim, Yong Deak Kim: Materials Chemistry and Physics Vol.106 (2007) p.369

The peak at 940 cm -1 is characteristic of out-of-plane νO-H bending mode in intermolecular hydrogen bonding dimmer structure.
Layered structure but no agglomerations of the gold clusters, on the film surface were observed for very thin films.
;Arsenault, A.C.; Nanochemistry-A Chemical Approach to Nanomaterials, The Royal Society of Chemistry, 2005
Letsinger , The DNA-Mediated Formation of Supramolecular Mono- and Multilayered Nanoparticle Structures, J.
[33] Wade, L.J.Jr., Organic Chemistry, 4th edition, Prentice Hall, 1999, p.64-65.

Effects of Al(OH)3 on the Structure and Properties of Foam Ceramics Cemented by Phosphate Caiyun JIA1,a , Rui DING 2,* Juncheng LIU3 , Anfa LIU4 and Dongxiao TENG5 1,2&3School of Materials Science and Engineering, Shandong University of Technology, Zibo Shandong 255049, China 4&5Gold Lion King Technology Ceramic Co.
Micro structure was observed by scanning electron microscopy (SEM, Sirion 200, Holland).
Fig.3 Micro structure of the sintered specimens (a) Pore morphology of the specimen; (b)-(d) The grain morphology of the samples with different Al(OH)3 amounts (0%, 10%, 20%) Effects of the Al(OH)3 amount on properties of green body and foamed ceramics Effects of the Al(OH)3 amount on properties of green body Fig.4 The effect of Al(OH)3 amount on the compression strength of the green body Fig. 4 shows the effect of the Al(OH)3 amount on the compression strength of the green body.
Materials Chemistry and Physics, 129(4) (2011) 326-330

Therefore, in this experiment, the smallest laser engraving width is used as the structure spacing to achieve the highest structure density.
The effects of the three laser engraving structures on the metal joining force were tested for the structures of round type, straight type and square type.
Among them, the depth of the laser structure has the greatest impact on the strength of the direct joining between plastic and metal, because the depth of the laser structure directly affects the amount of structure that the plastic can cover.
The results show that the square structure has better joining strength.
Trivinho-Strixino: Journal of Electroanalytical Chemistry, Vol. 780 (2016), p. 386-390

Results and Discussion Pore structure characterization on mortars.
Fig. 2 – Pore structure of mortars after 28 days of curing.
As expected from the data concerning the pore microstructure characterization reported in Fig. 2, the use of hydraulic lime instead of cement allows to achieve higher permeability to water vapour due to the formation of a more open porous structure.
Congress on the Chemistry of Cement, vol.
Lea: The chemistry of cement and concrete (Chemical Publishing, London 1971), p. 358.

Electrochemical Ceramic Device for Hydrogen-Phosphate Ion Sensor Youichi Shimizu1, a , Satoko Takase1, a and Mariko Yoshida1, a 1 Ceramic Chemistry Engineering Research Group, Department of Applied Chemistry, Kyushu Institute of Technology, 1-1 Sensui-cho, Tobata, City of Kitakyushu 804-8550, Japan a email, cclab@che.kyutech.ac.jp Keywords: Environmental Ion Sensor, Electrochemical, Ceramic Device, Hydrogen-Phosphate Ion, Perovskite-type oxide, Thin-film, Sol-gel, Impedance Transducer, Solid Electrolyte Abstract.
So far, oxide thin-films with perovskite-type structure have been prepared by dry processes such as sputtering and electron-beam deposition methods as well as wet processes of sol-gel methods mainly starting from metal alkoxides, organic acid salts [12, 13], or heteronuclear complexes [14].
At third, we have showed that the solid-state sensor combined with solid electrolyte impedance transducer and perovskite-type oxide receptor, which has a unique structure that has no electrode at the solutiion side, showed high sensing properties to HPO42- and it is applicable to a simple HPO42- sensor.
Amperometric Ion Sensing Properties of Perovskite-Type Oxide Thin-Film It is known that the poly (tetrafluoro- ethylene) (PTFE)-bonded carbon electrode loaded with La-based perovskite-type oxide powders with complex structure show high performance of amperometric sensing to hydrogen-phosphate ion [11].