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Phosphoric acid is a poliprotic acid and its dissociation occurs in three steps given three equivalence points for the chemistry system with pka different (Fig 1) [8].The protons are donates successively by the poliprotics acid with an acid constant that decrease significantly and give distinct values for each dissociation: Ka1 > Ka2 > Ka3.
According to the literature, HA has two types of water in its structure - adsorbed and lattice water [11,12].
Laborde, Materials Chemistry and Physics 80 (2003) p. 269-277
TenHuisen, Jounal of Solid State Chemistry 177 (2004) p.793-799.

Pt(IV) Adsorption Characteristics of Nanoporous Carbons Modified with Carboxymethylated Polyethyleneimine Yongju Jung1, Jei-Won Yeon 1, Ji Man Kim 2,a, Hyung Ik Lee 2, Seok Kim 3 and Soo-Jin Park4 1 Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, Yuseong-gu, Daejeon 305-353, Korea 2 Department of Chemistry and SAINT, Sungkyunkwan University, Jangan-gu, Suwon 440-746, Korea 3 Advanced Material Division, Korea Research Institute of Chemical Technology, Yuseong-gu, Daejeon 305-600, Korea 4 Department of Chemistry, Inha University, Nam-gu, Incheon 402-751, Korea a Corresponding author: jimankim@skku.edu Keywords: Pt, Nanoporous Carbon, Carboxymethylated Polyethyleneimine (CM-PEI), Adsorption, Langmuir Isotherm, Freundlich Isotherm, Temkin Isotherm Abstract.
Introduction Recently, nanoporous carbons have attracted great attention from many researchers due to their various application fields such as fuel cells, removal of toxic materials, and preparation of one-dimensional structured materials [1-4].

Synthesis of acetals and ketals catalyzed by H4SiW6Mo6O40/SiO2 Shuijin Yang1,a, Li Yu1,b, Yongkui Huang1,c and Guobin Duan1,d 1College of Chemistry and Environmental Engineering, Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, Hubei Normal University, Huangshi 435002, China ayangshuijin@163.com；byulisunshine@163.com；cxiaohuang2118@163.com；dduangb1987@126.com.
Heteropoly acids (HPAs) have found enormous applications in various industrially important classes of reactions such as alkylations, photodegradation and esterifications from the viewpoint of their variety of structures and compositions[4].
Anderson: Pyrrole chemistry part XX: synthesis of pyrrole acetals Vol. 3(1978), p. 295-297
Fan: Handbook of practice organic chemistry(Shanghai Science and Technology Press, Shanghai 1981), in Chinese

Hybrid catalysts compose of mono-substituted Keggin-polyoxometalate and different aminopyridine derivatives as catalysts for oxidation of benzyl alcohol with hydrogen peroxide Lijuan Chen1,a, Tao Feng2,b, Pengfei Wang2,c, Qingquan Liu1,d 1 School of chemical engineering and chemistry, Hunan University of Science and Technology, Xiangtan, China. 2 School of energy and dynamics engineering, Hunan University of Science and Technology, Xiangtan, China.
Introduction Catalytic oxidation of alcohols into corresponding carbonyl compounds has become important synthetic reactions with numerous applications in fine chemistry.
Experimental 2.1 Materials All the reagents used were chemically pure and analytical grade, the solvents, toluene and dichloromethane, were distilled before use according to the standard procedures. 2.2 Preparation of various substituted aminopyridine derivatives Various aminopyridine derivatives are synthesized by reduction of the Schiff base from an aromatic aldehyde and an aminopyridine with sodium borohydride [11], their chemical structures were showed in Scheme 1.
Cainelli and G.Cardillo, Chromium Oxidations in Organic Chemistry (Springer- Verlag publications, Berlin, 1984)

Alguno1,4,d 1Department of Physics, College of Science and Mathematics, MSU-IIT, 9200 Iligan City, Philippines 2Department of Chemistry, Caraga State University, Ampayon, Butuan City, 8600 Agusan del Norte, Philippines 3Department of Physical Sciences and Mathematics, Mindanao State University – Naawan Campus, Naawan Misamis Oriental, Philippines 4Primier Research of Science and Mathematics (PRISM), Mindanao State University - Iligan Institute of Technology, 9200 Iligan City, Philippines aaaronandrew.mutia@g.msuiit.edu.ph, breymarc.cumba@g.msuiit.edu.ph, c,*rycapangpangan@carsu.edu.ph, darnold.alguno@g.msuiit.edu.ph Keywords: silver nanoparticles, green synthesis, honey, UV-Vis spectroscopy, Dynamic light scattering, Fourier Transform Infrared spectroscopy, surface plasmon resonance Abstract.
The wavenumber 1027 cm-1 attributes to the C-C stretching of the carbohydrate structure.
Acknowledgments We acknowledge the support of DOST-ASTHRDP for the scholarship grant and the Department of Chemistry at Caraga State University for the equipment grant.
Yasumira, “Rapid biosynthesis of silver nanoparticles using culture supernatant of bacteria with microwave irradiation,” E-Journal of Chemistry. 6 (2009) 61–70

Flotation Over the past several decades, the chemistry of cassiterite flotation has been a subject of numerous studies.
However, for flotation of tin minerals such as cassiterite, much attention has been paid to flotation collectors and their surface chemistry [6], but most collectors which have been studied are sensitive to gangue containing calcium and magnesium, and are incapable of selective flotation of tin minerals from slimes.
Dissemination of cassiterite in the ore determines the structure of the processing flowsheet, including the particle size of separation, stages of grinding and separation, as well as the treatment of middlings.
BulatovicHandbook of Flotation Reagents: Chemistry, Theory and Practice, Published by Elsevier Ltd (2010) [4] Wills, B.A., and Napier-Munn,T.J., Mineral Processing Technology, 7th edition (2007)

It was presented that carbon nanospheres tend to agglomerate when their diameters are less than 1000 nm to form bead, necklace like structures [22]. 200 nm 1μm Figure 2: FESEM images of samples (a) 5,000 x and (d) 20,000 x.
[4] Kang Z. and Wang Z, Pairing of Pentagonal and Heptagonal Carbon Rings in the Growth of Nanosize Carbon Spheres Synthesized by a Mixed-Valent Oxide-Catalytic Carbonization Process, The Journal of Physical Chemistry. 100 (45) 17725 – 17731
The Journal of Physical Chemistry C 113 (2009) 10085 - 10089
Procedia Chemistry. 16 (2015) 328-333

The Influence of Microstructure on the Surface Charge of Sintered Hydroxyapatite Ceramics Darta Ubele1,a*, Liene Pluduma1,b, Karlis Agris Gross1,c 1Institute of Inorganic Chemistry, Riga Technical University, Paula Valdena 3/7, Riga, Latvia adarta.ubele@rtu.lv, bliene.pluduma@rtu.lv, ckgross@rtu.lv Keywords: hydroxyapatite, surface charge, electrical polarization, microstructure, contact angle.
Conditions that promote a larger grain size exhibit a larger polarization; since the polarization depends on grain size, chemistry and porosity, then all characteristics and polarization conditions should be stated to obtain a complete understanding of the most influential conditions for receiving a charged surface.
Eliott, Structure and Chemistry of the Apatites and Other Calcium Orthophosphates, Volume 18, First ed., Elsevier, London, 1994

However, the corrosion tendency of soil varies from one location to another due to great chemistry difference of the various soil type in China, which has been exacerbated the risk of external corrosion for the burid pipeline[8].
The corrosion behaviors of X80 steel in various simulated soil solution, containg all the ion species based on the soil chemistry analysis, were investigated using electrochemical tests, EDS coupled to SEM and weight loss method.
Chemical analysis was carried out to determine the soil chemistry by Beijing Center for Physical and Chemical Analysis, and the results were shown in Table 1.
Therefore, it can be found some products, having the cluster structure, were leaving on the outer surface after mechanical polishing.

Among them, hydrothermal or solvethermal method is regarded as a very effective and potential soft-chemistry route to tune the architectures of nickel sulfides.
A possible formation mechanism of β-NiS hollow spheres with cross-linked structure is also presented.
The NiS nanorods are single crystals with millerite structure.
The en molecules played a structure-directing role for the growth of the nanorods.
Bai, Chinese Journal of Inorganic Chemistry Vol. 27 (2011), p. 1219 [10] L.