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In this context, given the wide use of calcium phosphates (CaPs) and bisphosphonates (BPs) for the therapy of bone-related affections, there was great interest to investigate the chemistry taking place when combining the two systems since: (i) it could provide better insight in the mechanism of BP fixation on bones (ii) such combination could act as efficient BP delivery systems when implanted in bone defects.
Unlike calcium phosphate bioceramics in granules or pre-shaped form, CPC has the major advantage of being able to readily adapt to the shape of the bone defect, rapidly integrated into the bone structure and be transformed into new bone [15; 18-20] by the cellular action of bone cells (osteoclastic and osteoblastic ones) responsible for the local bone remodelling[17; 22-24].
Panel (a) shows the bone structure of a condyle implanted with a coated implant containing 2 µg Zoledronate (top) and the peri-implant bone (bottom), at magnification of 10× and 23×, respectively.
It was found that the bisphosphonate release from the coating positively influenced the structure of the trabecular bone and therefore the mechanical stability of the implant, which was correlated to the 20 µm area of bone around the implant, in agreement with a local delivery of the drug.
Journal of Molecular Structure, Vol.825(1-3), p.134

A Study on Waste Paper Reinforced Recycled Polypropylene Biocomposite Jevgenijs Jaunslavietis1,2,a, Jurijs Ozolins2,b, Martins Kalnins2,c, Galia Shulga1,d*, Brigita Neiberte1,e, Anrijs Verovkins1,f and Talrits Betkers1,g 1Latvian State Institute of Wood Chemistry, Dzerbenes St. 27, LV-1006,Riga, Latvia 2Riga Technical University, Paula Valdena 3, Riga, Latvia, LV-1048 aj.jaunslavietis@inbox.lv, bjurijs.ozolins@rtu.lv, cmartins.kalnins@rtu.lv, dgalshulga@inbox.lv, ebricis46@inbox.lv, fanrijs.verovkins@kki.lv, betalrits@gmail.com Keywords: recycled waste paper, recycled polypropylene, polymer-based bio-composite Abstract.
The presence of maleic anhydride grafted polypropylene as a compatibilizer increased the homogeneity of the structure of the bio-composite, which improved its mechanical properties and decreased its ability to be wetted with water.
The presence of maleic anhydride grafted polypropylene as a compatibilizer improves the compatibility of recycled polypropylene and crystalline cellulosic microparticles in the composite samples, as indicated by an increase in the homogeneity of their structure, an increase in their mechanical properties both in tension and bending, as well as a decrease in the ability of the samples to be wetted by water.

Bending strength of composite ceramics is a very sensitive physical defect to the organization and the impact factors are mainly due to phase composition, porosity and interfacial structure.
The porosity of 10NiO-NiFe2O4 composite ceramic prepared under the condition of doping order two is higher, but the bending strength is also higher, which clarified that the change of phase composition occurred in the NiFe2O4-NiO composite ceramics, thus the phenomenon is caused by the structure change of phase interface and result in the decrease of bending strength.
Therefore, the conductive change with the temperature T can be described by the general relationship: σ=σ0exp (-E/2kT) (2) Where E is the conductive activation energy, including the formation energy of defects and migration; k is Boltzmann's constant, which is a constant in a certain range and is determined by the concentration of charge carriers N in the material structure, charge quantity q, transition frequency δ, the average transition distance v0 and the ambient temperature T.
As is shown in formula 3, σ0 is determined by the crystal structure and lattice defects, which reflects these material parameters with temperature change degree.
Physical chemistry of inorganic materials[M].

Introduction In general, flow stress σ of metal during plastic deformation is governed by temperature T, strain rate , strain e and its own structure.
So, σ is usually described as a function of these variables, which is expressed by the most common equation σ=aenmexp(-bT), where, a, b as constant correlated with structure and temperature, n as strain hardened exponential, m as strain rate sensitivity coefficient [1-4].
The sub-structure with higher dislocations density was observed in the specimen deformed at 300℃ and 0.01s-1, as shown Fig.5 (a).
The cell structure with clear sub-grain boundary can be seen from Fig.5 (b).
Serajzadeh, N.Yazdipour: Materials Chemistry and Physics 101 (2007), p.153

[2,3,4] using different aluminum alloys as matrix with 20 % SiCp (micron sized particles) second phase, the observations show that after optimal SWC the dendritic structure of the initial matrix powder remain intact and hardness increment is similar across the composite's monolith.
In order to study the effect of a second phase in an aluminum-matrix alloy an aluminum powder (Al-1100) alloy is used, with a nominal size of 150 µm in a range size from submicron scale to 175 µm (Fig. 1a), it is also observable in the insert of Fig. 1a the rounded and irregular granules, with microdendritic structures.
In the case of lower explosive pad thickness, this can result in the presence of porosity associated with improper bonding; and with greater explosive pad thickness, porosity and defect structure result from melting and resolidification.
The same behavior occurs close to the consolidation axis, but irregular structures were clearly observed in the second aluminum base, (Aluminum-base 2, Fig. 6c).
Chemistry and Physics Vol. 85 (2004), pp. 438- 443.

Research on Emissions Characteristics and Treatment Technology of Black Carbon for Diesel Vehicle Chunyan Diao1,a, Jianfeng Li2,b 1 College of Chemistry and Environmental Science, Guizhou Minzu University, Guiyang 550025, China 2 Center for Atmospheric Science, University of Cambridge, Cambridge CB4 1DD, UK adiaoxuanji@126.com, b999forever@gmail.com Keywords: Black Carbon Emissions, Characteristics, Diesel Vehicle, Treatment Technology Abstract.
Adjusting the structure of energy consumption and transport portfolios, low-carbon or carbon-free transport can be developed.
As the protagonist of low carbon transport mode is the transport, it need build stereo transportation modes including water and underground, promote public transport and strengthen adjustment of transportation structure.
Abroad has taken a range of measures to reduce vehicle exhaust pollution, such as positively change fuel and improve combustion structure, study on high efficient exhaust treatment device, produce pollution-free prototype vehicles.
To design and improve engine combustion conditions from technology, processes, structure and principles make emissions of delivery vehicles standard [5].

Optimal process conditions ensure the quality of injection moulded parts, which is dependent on the polymer structure and its thermokinetics [2].
Especially the effects of injection velocity, pressure and holding pressure (basic parameters of injection phase of polymer injection technology) and mould temperature are considered on mechanical properties and internal structure of the final product.
The structure of the fracture surfaces was examined using a JEOL 7500F scanning electron microscope.
Structure vs. processing parameters, Eur.
Leyva-Porras, Effect of molding parameters on Young’s modulus of an injection molded low-density polyethylene (LDPE), Industrial and Engineering Chemistry Research 52 (2013) 5666-5671.

Petranovi� 2 1Vin�a Institute of Nuclear Sciences, Belgrade, Serbia and Montenegro 2Faculty of Physical Chemistry, Belgrade, Serbia and Montenegro Keywords: Boron, Carbon, Carbon Fibers, Composite, Glassy Carbon, Oxidation ABSTRACT Major weakness of all carbon-based materials originates from their poor oxidative stability.
RESULTS AND DISCUSSION As a first step, we investigated the influence of boron on the structure and oxidative stability of the matrix material, i.e. glassy carbon.
In the previous work of our colleagues [2], it is suggested that in a GCB sample with � 4 wt% of B (boron addition made via H3BO3) boron is substitutionally present in the GC structure.
X-ray diffraction patterns of our samples are given in Fig.1; all samples have two broad maxima corresponding to (002) and (10) reflections of a turbostratic carbon structure, which are typical of GC structure [2].

Synthesis and characterization of an experimental Zn-hydroxyapatite powders with application in dentistry Doina Prodan1a, Marioara Moldovan1b, Cristina Prejmerean1c, Laura Silaghi- Dumitrescu1d, Stanca Boboia1e, Violeta Popescu2f, Violeta Pascalau2g, Andreia Molea2h, Lazar Diana3i, Ioana Perhaiţa1j 1Babes Bolyai University - Raluca Ripan Chemistry Research Institute, Cluj-Napoca, 2Technical University of Cluj-Napoca; 3National Institute of Research and Development for Isotopic and Molecular Technologies Romania adoina_prodan@yahoo.com (corresponding author) , bmmarioara2004@yahoo.com, ccristina.prejmerean@gmail.com, dlauraiulia2000@yahoo.com, estancabobo@yahoo.com, fvioleta.popescu@chem.utcluj.ro, gvioletapascalau@yahoo.com, hmoleaandreia@yahoo.com, idiana.lazar@itim-cj.ro, jioana.perhaita@yahoo.com Keywords: Hydroxyapatite, FTIR, RDX, SEM, TGA, BET, size distribution Abstract In the present study, ZnO-hydroxyapatite (HA-Zn) was synthesized, thermally treated at different
The presence of traces of calcium hydroxide, calcium carbonate and especially of zinc oxide in the hydroxyapatyte structure is ideal for endodontic applications.
The structure model proposed by [6] explains the interactions between HA and ZnO and their influence on the bonding vibrations from the HA.
These differences can be explained by a possible rearrangement within the cell that may occur by entering the zinc oxide in hydroxyapatite structure [2, 3, 7, 8].
The heat treatment carried out on samples of HA-Zn causes changes in the structure, that are underlined by the changes in intensity of the absorption bands from FTIR spectra of the studied samples, as well as their position shifting in the spectrum.

These peaks confirm the crystalline structure of amethyst.
The combined results from XRD and XRF analyses confirm both the crystalline structure and the elemental composition of the amethyst that could be used as an additive for polymer matrix.
This decrease in strain could be attributed to the disruption of crystallinity of PVDF-HFP by amethyst, leading to a less ordered crystal structure and lower strain accommodation [16,17].
However, it is hypothesized that the high stress applied during tensile testing induces chain reorientation in the PVDF-HFP matrix, leading to a more ordered structure and continued increase in stress with reducing strain.
Al Ali Al-Maadeed, Electrospun nanofibers of PVDF-HFP composites containing magnetic nickel ferrite for energy harvesting application, Materials Chemistry and Physics. 239 (2020) 122257. https://doi.org/https://doi.org/10.1016/j.matchemphys.2019.122257