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The effects of different activation temperatures on the pore structure and surface morphology of highly efficient activated carbon (AC) derived from waste palm shell by chemical activation method using phosphoric acid as activating agent were studied.
Activated carbon is a processed carbon material with a highly developed porous structure and a large internal specific surface area.
The pore structure characteristics and the adsorption-desorption nitrogen isotherms of the resulting carbon were determined using a Micromeritics ASAP 2010 instruments.
This is due to the roles of impregnating agent that minimizes the formation of tar and other liquid, which could clog up the pores and inhibit the development of pores structures.
Ismadji, Activated carbon from jackfruit peel waste by H3PO4 chemical activation: Pore structure and surface chemistry characterization, J.

XRD confirmed that ZnO nanoparticles have the hexagonal wurtzite-type structure.
X-ray diffraction (XRD) analysis was used to investigate the crystalline phase and structure of the as-synthesized samples.
In the case of 0.01 M concentration (Fig. 3(b)), the primary nanoparticle size (~21 nm) is the lowest and is possible to distinguish hollow, porous, or crushed structure particles.
Chehimi, Stabilization of nano-structured ZnO particles onto the surface of cotton fibers using different surfactants and their antimicrobial activity, Ultrason.
Ali, Synthesis of ZnO Nanostructures Using Sol-Gel Method, Procedia Chemistry 19 ( 2016 ) 211-216

The aim of this study was to investigate the effect of pore diameter and acidity in the structure of silica catalysts on the process performances in terms of methanol conversion and hydrocarbon selectivity.
The purpose of this paper is to study the influence of pore size, acidity and structure on the product selectivity for conversion of methanol to hydrocarbon.
Another important property of zeolite 280 is its microporous structure, that consist of relative narrow pores providing size and shape selectivity for reactant.
Olah, Towards oil independence through renewablemethanol chemistry, Angew Chem Int Ed. 52 (2013) 104–107
Schwieger, Zeolitic materials with hierarchical porous structures, Adv Mater. 23 (2011) 2602–2615

Subsequently, a reactive ion etching (RIE) process was used to structure the poly-Si layer, followed by encapsulating the MOS stack in a high-temperature oxide (HTO), deposited via LPCVD at elevated temperature to enhance the deposition rate.
To investigate the atomic structure of the gate dielectrics after high-temperature processing, TEM analysis was carried out in a Thermo Fisher Scientific Talos F200X equipment.
The published results show that the transition from an amorphous to a crystalline structure by high-temperature annealing comes along with a decrease in reliability.
Avice et al., “Rearrangement of the oxide-semiconductor interface in annealed Al2O3/4H-SiC structures”, Applied Physics Letters, Vol. 91, no. 5, p. 052907 (2007)
Siddiqui et al., “High-k dielectrics for 4H-silicon carbide: present status and future perspectives”, Journal of Materials Chemistry C, Vol. 9, no. 15, p. 5055-5084 (2021)

Calcination at high temperature may also lead to changes in the CHA structure and decomposition of the carbonate compound in CHA.
All samples, regardless of the synthesizing method used, showed a similar XRD pattern; suggesting the sustainment of a regular pore structure.
This suggests that the heat treatment gave more energy for the rearrangement of the crystal structure.
Paluszkiewicz, "FTIR and XRD evaluation of carbonated hydroxyapatite powders synthesized by wet methods," Journal of Molecular Structure, pp. 657-661, 2005
Pierotti, J.Rouquerol, and T.Siemieniewska, "Reporting Physisorption Data For Gas/Solid Systems with Special Reference to the Determination of Surface Area and Porosity," Pure and Applied Chemistry, vol. 57 (No.4), pp. 603-619, 1985

Characterization The crystal structure and phase formation of the as-synthesized Fe3O4 and Fe3O4-MO NPs characterized powder X-ray diffraction (XRD) with Cu–Ka radiation.
These peaks demonstrate the cubic inverse spinel structure of Fe3O4, which are sharp and intense to be well crystallized structure.
These samples have a ferrite spinel structure in which the ions are filled at two tetrahedral and octahedral sites.
When an external electric field is applied to the nanoparticles, the electron jumps on the Fe2+ and Fe3+ cations in the octahedral structure increasing the polarization [24].
Iravani, Green Chemistry, 13, 2638 (2016)

The existence of those structure is due to less sufficient time to completely melt, thus there were several possible conditions on the surface of the substrate.
The cross-sectional area after flame spraying is shown in Fig. 1.b, it can be found that the structure produced by flame spray method is likely to be less regular and coarse, it is because the maximum flame temperature generated by this method, about 2700oC [13], causing the powders have less time to completely melt.
If compared to the as-flame sprayed structure (before oxidation test), the width of the TGO became larger and followed by the crack (see Table 2).
Ustel, Structure and durability evaluation of YSZ + Al2O3 composite TBCs with APS and HVOF bond coats under thermal cycling conditions, Surface & Coatings Technology. 205 (2011) 369–373 [9] J.G.
Wang, Fabrication and high temperature oxidation resistance of ZrO2/Al2O3 micro-laminated coatings on stainless steel, Materials Chemistry and Physics. 123 (2010) 731

For the catalytic proton acid, the pitch generates a rod like structure, and contains a lot of naphthenic structure in molecular structure, leading to excellent fluidity and low viscosity in carbonization, which is considered as a good precursor for manufacturing high performance carbon materials.
The peak of MCMB in the vicinity of the 43o is sharp than OMB, showing that MCMB a more regular graphite like structure than OMB.
Because naphthenic structure and rod like structure of pitch, so the molecular arrangement is loose, the pitch shows a low viscosity and high fluidity.
Naphthalene derived pitch contains more naphthenic and double bond structure, so, it is easy to be oxidized, leading to PMB infusible.
Sakai, Chemistry of synthesis, structure, preparation and application of aromatic-derived mesophase pitch, Carbon, 38(2) (2000) 305-328

Introduction In the 21st century, concrete is the most primary structure material in basic engineering construction.
The reason may be that there is enough water for cement hydration, leading to pore structure improvements.
Predicting the service life of concrete marine structures: an environmental methodology.
[3] Corrosion Prevention Technical Specification for Concrete Structures of Marine Harbour engineering (JTJ275-2000).
Chen, durability design of concrete structure, see: Chnezhaoyuan, Chenzhipeng, Jianjianqiong compile, durability and durability design of concrete structure memoir at the second engineering Developer Forum of China, Tsinghua University, Beijing, 2002, pp. 59-79

The different properties of the H and O-terminated surfaces are also reflected in ISFET structures.
This is indeed used in ChemFET structures based on (H-induced) surface channel devices [28, 29].
An example for such micromachined structure is a planar patch clamp array [40].
Chemistry, 38 (1998) 57 [11] R.
Ohtani et al.; Chemistry Letters 1998, 953 [26] T.