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The crystal structure of the samples is studied by X-ray diffractometer (Bruker, Germany) with CuK-α anode radiation at 2θ range of 17-60 ° (λ = 1.54 Å).
Each sample's surface composition and chemistry were investigated using FTIR spectroscopy (Shimadzu, Japan) at 400-4000 cm-1 wavelength.
All of the peak position is well-indexed to vivianite’s structure, which is consistent with Fe3(PO4)2·8H2O PDF card 75-1186.
Chien et al., “Modifying the morphology and structure of graphene oxide provides high-performance LiFePO4/C/rGO composite cathode materials,” Adv.
Pan, “Structure and performance of the LiFePO4 cathode material: From the bulk to the surface,” Nanoscale, vol. 12, no. 28, pp. 15036–15044, 2020, doi: 10.1039/d0nr03776a

Relatively high density is based on the morphological structure that provides the crystallinity level up to 80%.
Lignin also belongs among natural polymers, however, its structure is amorphous.
Lignin is excreted mainly on secondary walls where it acts as a bonding agent that surrounds cellulose and hemicellulose structures.
The higher content of crystalline structures in the matrix, the higher volues of HDT are reached [28].
Seymour/Carraher's Polymer Chemistry. 7th edition.

Mitchella Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1 a karm@chem.ubc.ca Keywords: Aluminum alloy; Chromate conversion coating; Photoelectron spectroscopy; Scanning electron microscopy; Scanning Auger microscopy; Raman spectroscopy Abstract.
For this particle, a rough spongy structure developed, and the SAM point analyses confirmed depletion of Mg and Al leaving a surface basically composed of Cu and O.
The vertical lines identify structure characteristic of metallic and oxide components.
Fig. 1d gives an example of a previously dealloyed Al-Cu-Mg particle, with its halo-like structure, which is now covered with CCC.
More detailed analysis of Auger Al KLL spectra revealed appreciable structure characteristic of Al oxide at all surface locations (compare spectra numbered (3) and (4) in Fig. 3).

Conclusions and Perspectives Modeling structure development in polymer processing needs physically and thermodynamically based laws.
Possible domains are bio-polymers, geology-mineralogy, marine biology, chemistry, etc.
Zhang, Shish-kebab-like cylindrulite structures resulted from periodical shear-induced crystallization of isotactic polypropylene, Polymer 52 (2011) 2970-2978
Chenot, Modeling of structure development during polymer processing.
HAUDIN, MODEL EXPERIMENTS AND STRUCTURE DEVELOPMENT IN HIGH-PRESSURE CRYSTALLIZATION: THE CRISTAPRESS PROJECT, REV.

The different surface chemistry for copper was observed by varying combination of H2O2 and HCl in etchants.
As a result, the chemical etch process, whereas the morphological and chemical structure of the etched copper can be easily tailored by means of varying the concentrations of H2O2 and HCl.
Table 2 Topological pattern, chemical structure and wettability of the bare and etched copper Etchant Topological pattern Chemical structure No no texture Cu 0.1% H2O2/2M HCl no distinctive features Cu 1% H2O2/2M HCl nanotexture CuCl 2.5% H2O2/2M HCl nanotexture CuCl 1% H2O2/1M HCl nanotexture - 1% H2O2/4M HCl no distinctive features Cu Tribological performance of the etched copper.
Conclusions This work demonstrates that by varying etchant composition, it is possible to modify the topography, chemical structure, tribological performance of copper.
Rapoport, Friction, wear and structure of Cu samples in the lubricated steady friction state, Tribol.

Data concerning amber composition and structure have been obtained with the help of instrumental techniques, physico-chemical and spectral analysis, and geological investigation of the deposits.
Composition of amber and its structure are still under study.
Size of negative structure is minor (240 km² according to data of geological surveying); its form is close to a tetragon; it is limited by ruptures.
Within the larger territory, dark-greenish-gray clay of early Oligocene or structured kaolinized weathering crust of crystalline rocks is water-proof rock.
Open Chemistry, 7(3). doi:10.2478/s11532-009-0053-8 [25] Kuz’menko, O., Petlyovanyy, M., & Stupnik, M. (2013).

Hence, the barrier for nucleation, i.e. the interfacial energy σsl, depends on the structure of the nucleus.
The dependence of the activation energy on the crystallographic structure of the nucleus has a strong impact on the solidification of metastable phases.
Meanwhile, the negentropic model of Spaepen has been extended for numerical calculations of interfacial energies of complex structures such as superlattices with large unit cells [5].
Structure and microstructure analysis of the as-solidified samples at room temperature are often misleading concerning the phases formed during the early stage of solidification.
Walker, in The Physical Chemistry of Process Metallurgy, edited by G.R.

To make the most of these fibers as reinforcements, it's important to examine their characteristics such as the structure, thermal, and mechanical properties.
For instance, research on Junchus effusus L. fibres has suggested their structure may be helpful as a bio-based material [2].
Hemicellulose features a large open hydroxyl structure that can absorb and retain water, which can weaken natural fibres; however, treating the fibres with an alkaline solution can mitigate this issue [25].
Omar, Chemical composition, anatomy, lignin distribution, and cell wall structure of Malaysian plant waste fibres, BioResources. 1 (2) (2006) 220–232
Liu, Orientation of carbon fiber in magnesium-doped hydroxyapatite and its effect on mechanical and tribological properties of carbon fiber reinforced composites, Materials Chemistry and Physics. 306 (2023) 128078. https://doi.org/10.1016/j.matchemphys.2023.128078

The first (usually more intense) is associated with the recombination of Frenkel excitons localized on defects of the crystal structure ("deep X-traps").
As a rule, such transformations are accompanied by a strong "red" or "blue" shift of the luminescence onset, which obviously corresponds to the new energy position and structure of the HOMO and LUMO molecular orbitals of the resulting substance.
Naturally, the structure of the energy spectrum of condensed matter, for obvious reasons, is richer than that of an individual molecule, and this is reflected in the corresponding emission spectra.
The presence of such substances in the studied samples, even in the form of impurities, can lead to both a noticeable complication of the crystal luminescence structure and to a non-uniform broadening of its bands.
Computational and Theoretical Chemistry, 1212 (2022) 113690.

The specific method incorporated super-absorbent polymers to provide water within the material’s structure and maintain RH at high levels.
The variety of aspects such as the amorphous structure and thermodynamic assumptions diminish the opportunity of predicting concrete performance.
This specific phenomenon will be intensified in a real structure due to the provided structural restrain, leading to extended cracking.
Taylor, “Cement chemistry,” Library (Lond)., 1990
Rashid, “Effect of Casting Temperature on Bond Stress of Reinforced Concrete Structure,” vol. 13, no. 2, 2013