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Introduction Zirconium oxide has found multiple applications in chemical and environmental chemistry, including its appliance as catalyst and support due to both, acidic and basic surface sites [1].
Despite zirconia are intensely studied, there are few works dedicated to the study of the influence of the precursor over the structure and textural characteristic of ZrO2 solids.
It has been found that the structure and porosity of these ZrO2-Mn oxides can be tailored by means of the control of some parameters such as the kind of precursor and the zirconium hydrolysis rate.
For the Mn-doped samples synthesized by method A, the XRD patterns show that the manganese is well dispersed in the structure of the zirconia and the combination with the surfactant produces wide peaks associated with small particles.
These synthesis methods allow the formation of mesoporous zirconia owning disordered structures as confirmed by TEM and the low angle XRD analyses, suggesting that the porosity arises from the spaces among particles.

In nanocrystalline diamond films, the nature of the grain boundaries with π bonds (sp2) provides mechanical, electrical, optical properties and surface chemistry [10,11].
The morphology and structure effects related to these transitions of the films were evaluated by atomic force microscopy (AFM), Raman spectroscopy and infrared spectroscopy (FTIR).
Results and Discussion The morphology and structure of these films showed different properties.
The transition from ultrananocrystalline growth (renucleation process) to a columnar structure of NCD films during grown.
The results revealed that the surface morphology as well as the grains size, diamond structured, doping concentration and the growth mechanisms depend strongly on the argon ratio in the reactants gases.

The purity of the sample has been very high, but due to the presence of positive and negative β-carotene and some impurities with the similar structure, the conventional extraction methods such as recrystallization cannot further purify the samples.
As HSCCC has obvious advantages compared with traditional separation and purification methods, this technology has been widely used in the separation of traditional Chinese medicine ingredients, health food, biochemistry, bioengineering, natural product chemistry, organic synthesis, environmental analysis and other fields [13-16].
As β-carotene has an infrared inactive symmetrical structure, the absorption peaks of 11 C=C bonds in the molecular chain are very weak, which are shown as the weak absorption peaks at 1600-1680 cm-1 in the figure.
There are seven groups of H-NMR peaks in the spectrum, representing seven kinds of hydrogen atoms with similar chemical environment in β-carotene structure.
In figure 5b, there are 18 groups of 13C NMR peaks in the spectrum, representing 18 groups of carbon atoms in different chemical environments of β-carotene structure. β-carotene is a symmetric structure.

The microarc coatings have a double structure composed of an inner barrier type layer and an outer porous layer [4].
Physicochemical properties of the surface, like wettability, surface topography and chemistry, are of prime importance for better adhesion, spreading and proliferation of cells [4].
It has been seen that the main components of structure are spherolytes with pores.
The phase structure of the coatings does not depend on process parameters.
Structure and properties of cast binary Ti-Mo alloys, Biomaterials 20 (1999) 2115-2122

PUR elastomers are very similar to rubbers, their structure being characterised by more regular netting, which results in greater strength.
The chemical structure and functionality of the isocyanates can also influence the adhesive properties significantly [10][11].
These are, in particular, aggressive vapours or liquids that can penetrate the bonded material or enter the joint structure through the joint.
Journal of Industrial and Engineering Chemistry 18 (2012), 1620-1627
[14] ČSN EN 1542 – Products and systems for the protection and repair of concrete structures.

However, the complex structure of raw biomass is recalcitrant and subjected to acid hydrolysis to break down the bonds to simpler forms for further conversion to various derivative products.
The porous structure of the calcined carbon cryogel was observed through scanning electron microscopy (SEM) using a Fei Quanta 400F (Hillsboro, OR, USA) scanning electron microscope operating at 20 kV accelerating voltage.
The removal of waxy materials allows the access of solvent molecules to the raw feedstock, hence enhancing the swell of biomass and facilitating the catalyst binding to the porous structure.
The porous structure of the catalyst is another important factor in enhancing the binding activities between catalyst and substrate.
Conclusion The conventional LA synthesis from direct conversion of biomass in one-pot reaction is challenging and needs to overcome multiple bottlenecks, which include the complexity and recalcitrance of biomass structure, low product yield, low selectivity of catalyst, low recovery of catalyst, and unclean and costly production.

The inverse pole figure maps of the corresponding alloys, recorded by the orientation imaging mapping technique, display remarkable difference in the grain structure through the thickness of the sheet (10,11).
The surface grain size and structure is unique in pure iron and ultra low carbon steel, which display a slightly columnar monolayer of predominantly <100> oriented surface grains on top of a matrix consisting of equi-axed <111>//ND bulk grains.
The laboratory cast alloys L302 and L296 display a similar grain structure and grain size, which is confined to the surface and extends to a few microns (15-30 microns) underneath the surface.
The variation in results could be attributed to alloy chemistry and impurities in annealing atmosphere during phase transformation annealing.
Contrastingly, the ULC steel alloyed with silicon shows a wider oxidation with layer extending to approximately 1µm with a dense structure which apparently inhibits the role of surface energy anisotropy.

It was found in our laboratory that the cation exchange resin (CER) of LSD-001 which has cation exchange group SO3H and macroporous structure showed a good adsorption ability for cordycepin.
The resin’s adsorption and desorption capabilities are related to the functional groups, structure and polarity of the resin, Cordycepin has several polar functional group including two hydroxyl (−OH), one amino (−NH2), four nitrogen atoms and one oxygen atom in its structure, so it exhibited some polarity and could be ionized to cation (NH3+ group of cordycepin) in acid solution.
The two MARs employed belong to the cross-linked styrene–divinylbenzene (DVB) structure without functional group, so it showed lower adsorption performance for cordycepin.
Therefore, the resin LSD-001 was finally selected as the optimum resin owing to its performance of cation exchange group and macroporous structure.
Journal of Agriculture and Food Chemistry Vol.58, No.22 (2010), p. 11645 [3] R.

Polysulfone has choosen as polymer because it have highly strength structure on high temperature and chemical resistant [21].
Rampun, Removal of natural organic matter for wetland saline water desalination by coagulation-pervaporation, Journal of Scienctific & Applied Chemistry. 22 (2019) 8
Ji, Evaluating the Removal of Organic Fraction of Commingled Chemical Industrial Wastewater by Activated Sludge Process Augmented with Powdered Activated Carbon, Arabian Journal of Chemistry. 15 (2015)

Electrochemical Deposition of Polyaniline on Carbon Steel for Corrosion Study in Geothermal Solution Gabriela Aristia1,2,a*, Le Quynh Hoa2,b and Ralph Baessler2,c 1Department of Physical and Theoretical Chemistry, Freie Universität Berlin, 14195 Berlin, Germany 2BAM - Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin, Germany a*gabriela.aristia@fu-berlin.de, bquynh-hoa.le@bam.de, cralph.baessler@bam.de Keywords: corrosion, electrochemical deposition, polyaniline Abstract.
Georgolios, Formation of conducting polyaniline coatings on iron surfaces by electropolymerization of aniline in aqueous solutions, Journal of Electroanalytical Chemistry 429 (1997) 81-93
Jenkins, The formation of polyaniline and the nature of its structures, Polymer 37 (1996) 367-369