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Chalcogenide materials are ideal for IR applications because of their wide transmission window, variable bandgap, and high nonlinearity. In this regard, optical characteristics of (Dy) doped (GeTe2)80(In2Te3)20 thin films have been measured and investigated. The influence of annealing on the optical characteristics of thin films has been reported. The reflectance and transmittance spectra were used to calculate the refractive index (n) and extinction coefficient (k) of thin films. With the annealing of as-prepared film, the penetration depth (Δ) measured at a wavelength of 1.1 μm and bandgap (Eg) decrease. The relaxation process has been realized using electric modulus (M) determination, and the dielectric loss has been estimated in terms of loss tangent (tan δ). Wemple Di-Domenico (WDD) model has been employed to calculate dispersion energy (Ed) and average energy gap (E0). Using the values of E0 and Ed, the static refractive index (n0) and the moments (M-1, M-3) of the optical spectra have been determined. Sellmeier oscillator parameter (λ0) increases while So decreases with a rise in the annealing temperature.

The Bulk (100-x)Ge3Se7 - (x)As2Te3 (0 ≤ x ≤ 30) glassy alloys were prepared using the melt quenching technique. The elastic moduli (Bulk (K), Micro-hardness (H), Young (Y)), and Poisson's ratio (Pr) of the prepared glasses have been determined using the measured values of the ultrasonic velocities and density (ρ). Values of ρ were measured, then the molar volume (Vm) was estimated theoretically. The DSC thermograms are used to determine the glass transition temperature (Tg). The thermal evaporation method was used to prepare the (100-x)Ge3Se7- (x)As2Te3 (0 ≤ x ≤ 30) thin films under a vacuum of about 10−4Pa. The absorbance (A) of the films in the spectral range from 0.45 to 0.85 μm has been measured, then the absorption coefficient (α) and energy gap (Eg) were determined. The Chemical Bond Approach (CBA) has been used successfully to estimate theoretically various physical and structural characteristics of the studied system. Theoretical values of Eg and Tg have been obtained using different methods. The results proved a remarkable agreement between the theoretical and experimental values for both the Eg and Tg. The Eg values decreased from 2.1 to 1.73 eV by increasing the As2Te3 content from 0 to 30 at. %. Therefore, these compounds can be used as an absorbing layer for electromagnetic radiation in photovoltaic devices and sensors.

In this study, salicylaldehyde (SA) and n-hexylamine (Hex-NH2) were used to produce 2-[(E)-(hexylimino)methyl] phenol (SA-Hex-SF), which was then reduced by sodium borohydride to obtain 2[(hexylamino)methyl]phenol (SA-Hex-NH), and finally the SA-Hex-NH reacted with formaldehyde to afford a new benzoxazine precursors (SA-Hex-BZ). Then, the poly(SA-Hex-BZ) was prepared through thermal curing polymerization of its monomer at of benzoxazine at 210 oC. The chemical structure of the SA-Hex-BZ was analyzed using FT-IR, 1H, and 13C NMR spectroscopy. The thermal properties, surface morphology and crystallinity of the SA-Hex-BZ and its PBZ polymer were studied by differential Scanning Calorimetric (DSC), TGA, scanning Electron Microscopy (SEM), and X-Ray analysis, respectively. poly(SA-Hex-BZ) was easily prepared on mild steel (MS) via spray painted and thermal curing methods. Finally, the electrochemical measurements were applied to measure the anticorrosion properties of MS coated with poly(SA-Hex-BZ). This work demonstrated that PBO coating was hydrophobic and had a high anticorrosion effect on MS with efficiency was 91.7%.

The Ag-mixed $${\text{Se}}_{70}{\text{Te}}_{30}$$ thermally deposited semiconducting thin films show interesting thermoelectric properties. As the Ag content in the structure of $${\text{Se}}_{70}{\text{Te}}_{30}$$ increases, the Seebeck coefficient increases. The semiconductive thin films reveal a p-type behavior. The dark conductivity increases at 300 K, whereas a reduction in $$\text{c}\text{o}\text{r}\text{r}\text{e}\text{s}\text{p}\text{o}\text{n}\text{d}\text{i}\text{n}\text{g}$$ activation energy for dark, photo and thermal response is observed with the increase in the Ag content. It is elucidated that the power factor for $${\left({\text{Se}}_{70}{\text{Te}}_{30}\right)}_{100-x}{\text{Ag}}_{x} (0.0\le x \le 8.0\; {\text{at}}.{\%})$$ semiconducting thin films can be tuned and enhanced at varied temperature ranges through adjusting the addition amount of Ag. These results indicate that these semiconducting thin films have remarkable potential as thermoelectric generators.

Alkali boro-bismuthate glasses modified with MoO3 were explored using DTA. The activation energies for glass transition (Eg) and crystallization (Ep) were evaluated using the heating rate dependence of the glass transition temperature (Tg) and the peak temperature of crystallization (Tp), respectively. The study indicated a decrease in Tg, Tp, Eg, and Ep as a function of the MoO3 and Bi2O3 contents. This decrease is ascribed to changes in the alkali borate network. XRD was used to confirm the results of this study. The XRD analysis revealed the existence of crystalline phases such as Na2B4O7, Bi2MO6, and B1.5Mo0.25O3 in the amorphous alkali borate network. The kinetic exponents n and m that determine the crystallization reaction mechanism in the glasses were obtained using the experimental values of the crystallized volume fraction (χ). With the increase in x content, the n values decrease, which may be ascribed to the transformation from the three-dimensional network to the one-dimensional network, which decreases $$E_{p}$$ values and crosslink density.

In the literature a widely spread equation to correlate between the optical (σoptic) and electrical (σelec) conductivities is in the form of ( $$\sigma_{\text{elec }} = \frac{2\lambda \sigma_{\text{opt}} }{\alpha }$$ ). Unfortunately, the two sides of this equation have different dimensions i.e., this equation is incorrect and the work by this equation must be stopped.

In this study, highly effective radiation shielding glass materials with different amount of CdO additive were investigated in terms of nuclear shielding performance. Moreover, mechanical properties have been determined. The μm values were computed using XCOM and XMuDat program. The gamma and neutron shielding parameters such as μm, HVL, Zeff, EBF, EABF, SAFE, bco, bico, σco and σabs are calculated to understand the radiation shielding performances of investigated glasses. The results show that μm, Zeff and σabs values increase as the CdO content increases. The S7 sample has the lowest HVL, MFP, EBF, EABF, SAFE, bco, bico and σco values. Therefore, S7 glass sample (70 mol% of CdO) which has also the highest number of bonds per unit volume can be considered as a superior material for radiation shielding applications. The outcomes of this study can be very useful for future applications of investigated glass materials in medical and industrial radiation fields.

Luminescent coatings may provide low-cost techniques for studying the corrosion mechanism of coatings and for getting an early indication of corrosion processes. Here, a series of conducting copolymers and their nanocomposites has been synthesized and the effect of adding bulky moieties and/or nanocomposite formation on the solubility, thermal stability, corrosion inhibition, and photoluminescence of these copolymer coatings has been investigated. A significant enhancement in both solubility and thermal stability of the copolymers has been demonstrated upon the nanocomposite formation or presence of bulky groups. The nanocomposites displayed an inhibition efficiency of 97% for mild steel corrosion in an acidic environment which is much higher than that of the corresponding copolymers. Interestingly, the as-prepared copolymers and nanocomposites with tert-butyl group displayed an aggregation-induced emission with quantum yields higher than analogs without the tert-butyl group. Quantum chemical calculations attributed this enhancement in the quantum yields to the change in the degree of π-π interactions between the polymer chains. Moreover, aggregation-controlled luminescence has been demonstrated for the prepared copolymers.

The current study focused on the impact of arsenic additions on the mechanical, and electrical properties of binary As-Se glasses. Different elastic parameters such as micro-hardness (H), Poisson's ratio (σ), Young (Y)-, and bulk (K)-moduli) as well as Debye temperature (TD) for As-Se glasses were determined based on the measured values of the ultrasonically speeds (transfer, vl, and shear, vs). The activation energies for electrical (ΔEdc) and for thermoelectrical conduction (ΔEthermo) of these glassy thin films were investigated as a function of composition. Y, K and ΔEdc were correlated with the glass transition temperature (Tg). The obtained results were discussed in terms of the average coordination number, crosslink density and overall mean bond energy.

The current study focuses on the impact of As addition on the thermal, mechanical, electrical and thermoelectric properties of ternary $${\text{Bi}}_{0.02} {\text{As}}_{\text{x}}\,{\text{Se}}_{{0.98 - {\text{x}}}}$$ ($$0.02 \le x \le 0.08$$) glasses. Different elastic moduli such as the micro-hardness (H), Young’s modulus (Y), bulk modulus (K), Poisson’s ratio (Pr) and shear modulus (S) as well as Debye temperature (TD) for the studied glasses were estimated by using the measured values of the ultrasonic speeds (transfer, vl, and shear, vs) and density (ρ). Moreover, the measured values of the dc electrical conductivity (σdc) and thermoelectric power (Sthermo) were used to estimate the activation energies for the electrical (ΔEdc) and for thermoelectric (ΔEthermo) conductions, respectively. It was found that σdc increases, whereas Sthermo, ΔEdc and ΔEthermo decrease with increasing the As content for the $${\text{Bi}}_{0.02} {\text{As}}_{\text{x}}\,{\text{Se}}_{{0.98 - {\text{x}}}}$$ ($$0.02 \le x \le 0.08$$) thin films. In addition, replacement of Se with As atoms results in an increase in the average coordination number (CN), cross-linking density (Cd), cohesive energy (CE), ρ, H, Y, K, S and TD, whereas the molar volume (Vm), Pr and the homopolar Se–Se bonds decreased. Both of Y and K as well as ΔEdc are correlated with the glass transition temperature (Tg).

Chalcogenides are motivating members of crystalline and/or amorphous materials because of their use in many application devices as optoelectronics, detectors of thermally imaging, optical waveguides, recording materials, solar cells, bio- and chemical-sensors. Bulk samples for ternary G e 26 C u x T e 74 − x ( 2.5 ≤ x ≤ 12.5 a t . % ) glasses were prepared using the well-known melt quenching method. Thermal evaporation method has been used to prepare thin films. The amorphous state of the prepared films was confirmed by X-ray diffraction (XRD) and scanning electron microscope (SEM). The dark dc-electrical conductivity (σdc) and Seebeck coefficient (S) were measured over an extensive range of temperature (300–450 K). The activation energies for electrical conduction ( Δ E d c ) and thermoelectric effect ( Δ E s ) decrease with an increase of Cu content. This reflects the observed increase in the carrier concentrations ( n σ for electrical conduction and ns for thermoelectric). With the addition of Cu content, the defects as the weak Te–Te homopolar ponds (1.43 eV) increase which may tend to lower the energy of the conduction-band edge. Consequentially, both of the Δ E d c and the optical band gap ( E g ) decrease with the increase in Cu content. The obtained results for the dc conductivity and the Seebeck coefficient may lead to a high value of the power factor. The current study is carried out to obtain high-efficient films for their using in the potential applications of thermoelectric phenomenon by an easy, simple, and low economic cost methods. A good correlation between the activation energy for electric conduction ( Δ E d c ) and the glass transition temperature (Tg) has been established.

The electric conductivity and thermoelectric power for different compositions of the chalcogenide glasses (SbSn)xSe100−x (x = 4, 8, 12, 16 and 20 at.%) were measured experimentally. The dc conductivity is found to have an Arrhenius behavior in the temperature range (300–450) K with typical activation energies decreasing from 0.87 to 0.74 eV with the SbSn content. The concentrations of charge carriers, as well as their mobility and characteristic relaxation time were deduced in the same temperature range and compositions. The variations of activation energy calculated from measured electric conductivity versus SbSn content are compared to the behavior of calculated half band gap. From the measured Seebeck coefficient, we deduced its specific activation energy and found that it is lower than that related to electric conductivity. This difference is assumed to be the activation energy needed for polaron hopping. The increase in cross-linking with SbSn content is proposed as an explanation for the increase in polaron-hopping activation energy.

A novel benzoxazine (BA-BZ-COOH) monomer has been prepared and its structure has been proved using various measurements. PBA-BZ-COOH/nanocomposites reinforced with varying content of modified nanoclay (MNC) have been prepared in situ polymerization method for superior thermal, optical, and anti-corrosion properties. The resulting nanocomposites are showed a good dispersion of MNC in the PBA-BZ-COOH matrix without aggregates and a partial intercalated/exfoliated structure. The PBA-BZ-COOH/MNC (3%) composite that cured at 210 °C had high glass transition temperature (190 °C), and high UV shielding (97 and 85% at wavelength 275 and 375 nm, respectively). Finally, PBZs nanocomposites with varying contents of MNC (0.5, 1, 2, and 3%) were prepared as coatings on MS and their anti-corrosion performance were discussed in detail. The electrochemical results showed enhanced the polarization resistance of nanocomposites coatings with the increase of MNC content and the capacitance value for PBA-BZ-COOH/ MNC (3%) composite coating was reduced by about one orders of magnitude (0.00937 µF cm2), compared with the neat PBA-BZ-COOH coating (0.01306 µF cm2). Thus, PBA-BZ-COOH/MNC nanocomposites can be widely used for many industrial applications.

The physical properties of Cu-doped S-based ternary glassy alloys have been examined experimentally and theoretically. The $${\text{Cu}}_{2x} {\text{Ge}}_{30 - x} {\text{S}}_{70 - x} \left( {0.0 \le x \le 5.0 {\text{at}}.\% } \right)$$ chalcogenide glasses have been prepared using the well-known melt quenching method. It was found that the coordination number increases from 2.6 to 2.7 with increasing the Cu content from 0 to 10 at %. As well, the glass density and compactness are increased, while the molar volume is decreased. The cohesive energy and the average heat of atomization show similar behavior with the enhancement of Cu in the Ge–S binary glasses. It was found that the optical band gap values decrease from 2.75 to 2.28 eV with increasing the Cu content. From the results of the investigated samples, the covalency parameter is greater than 84%, so that these glasses can be used as stable glass former. The elastic moduli (bulk (K), micro-hardness (H), Young (Y)) and Poisson’s ratio (ơ) of the prepared glasses were estimated using the ultrasonic velocities (longitudinal (vL) and transverse (vT)) and the density (ρ).

We report the optical properties of thermally evaporated rare-earth (Dy) doped (GeS2)80(In2S3)20 thin film. Film of thickness 1100 nm has been deposited on a microscopic glass slide, and the as-prepared thin film has been characterized using X-ray diffraction, energy dispersive spectroscopy and UV–visible–near infrared spectroscopy. With annealing temperature, the refractive index is noticed to decrease from 2.51 to 2.27, while the optical bandgap is observed to increase from 2.03 to 2.29. The dispersion of the refractive index n for as prepared and annealed thin films have discussed using the single oscillator model proposed by the Wemple–Di Domenico relationship. The observed value of Eo (5.31–4.40 eV) and dispersion energy Ed (28.22–18.18 eV) are decreasing for as prepared and annealed thin films. The increase of bandgap has been explained in terms of the disorder in the system.

Herein, we synthesized two new phthalimide-functionalized benzoxazine monomers, pPP-BZ and oPP-BZ, through Mannich reactions of 2-(4-hydroxyphenyl)isoindoline-1,3-dione (pPP) and 2-(2-hydroxyphenyl)isoindoline-1,3-dione (oPP), respectively, with p-toluidine and paraformaldehyde. The structures of these two monomers were confirmed using Fourier transform infrared (FTIR) and nuclear magnetic resonance spectroscopy. We used differential scanning calorimetry, FTIR spectroscopy, and thermogravimetric analysis to study the polymerization behavior and thermal stability of the monomers and their corresponding polybenzoxazines. Poly(pPP-BZ) and poly(oPP-BZ) were formed on mild steel (MS) through spin-coating and subsequent thermal curing polymerization. We used various corrosion testing methods to examine the effect of the curing temperature on the corrosion resistance of the coated MS samples in 3.5 wt.% aqueous solution of NaCl. Among our tested systems, the corrosion rate reached a low of 2.78 &micro, m&middot, Y&minus, 1 for the MS coated with poly(pPP-BZ)180 (i.e., the coating that had been cured at 180 &deg, C), this value is much lower than that (4.8 &micro, 1) reported for a maleimide-based benzoxazine compound (MI-Bz)/33 wt.% ACAT (amine-capped aniline trimer) blend. Thus, the incorporation of the imide functional group into the PBZ coatings is an effective strategy for affording high-performance corrosion resistance.

Discovering renewable energy resources is receiving increased attention both in industrial and academic research. Vegetable oils are a promising route to renewable chemicals and polymers due to their ready availability, inherent biodegradability, and low toxicity. Also, bio-renewable fuels have been prepared from vegetable oils. Here, the soy oil monoglyceride has been obtained from the soybean oil by alcoholysis, and its structure was confirmed by the spectral analyses. To increase the yield of the monoglyceride formation and to prevent the ester interchange reversible reaction, we found that rapid cooling of the mixture with high-speed stirring allowed the best yield of soy oil monoglyceride. Then, three new polyester resins have been synthesized by the reaction of the monoglyceride with phthalic and/or maleic anhydrides with different ratios. The synthesized resins have been characterized by spectral analyses, and their morphological and physico-chemical properties such as acid value, iodine value, volatile matter content, and viscosity have been studied. The three polyester resins were soluble in common organic solvents. The effect of phthalic and maleic anhydrides ratio on the physical and chemical properties of the resin was also studied. The incorporation of maleic anhydride decreases the iodine value of the resins compared to phthalic anhydride-based resin.

In this study, we prepared nitrogen-doped microporous carbons (NMCs) from two different benzoxazine monomers (AMBZ, AEBZ), each containing both azobenzene and carboxylic groups, through a simple and environmentally friendly process of ring-opening polymerization (ROP), calcination, and KOH activation. We synthesized the AMBZ and AEBZ monomers through Mannich condensations of 4,4′-diaminodiphenylmethane (M) and 4,4′-diaminodiphenyl ether (E), respectively, with paraformaldehyde and 4-(4-hydroxphenylazo)benzoic acid (Azo-COOH). Differential scanning calorimetry (DSC) revealed that the thermal curing temperatures of AMBZ and AEBZ (both ca. 230 °C) were lower than that of a typical Pa-type benzoxazine monomer (263 °C), suggesting that the azobenzene and COOH units acted as promoters and catalysts for the ROP of the benzoxazine units. In addition, after ROP of the benzoxazine units of AMBZ and AEBZ, the polymers PAMBZ and PAEBZ, respectively, displayed high glass transition temperatures (Tg) and high thermal stability, as evidenced using DSC and thermogravimetric analysis (TGA), due to their greater cross-linking densities. We used Brunauer–Emmett–Teller analysis, TGA, wide-angle X-ray diffraction, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy to examine the specific surface areas, porous structures, chemical compositions, and thermal stabilities of the resulting KOH-activated NMCs PAMBZ-A and PAEBZ-A. The CO2 capture abilities and thermal properties of these two highly-nitrogen-doped microporous carbons, synthesized from polybenzoxazine (PBZ) resins containing azobenzene and COOH groups, were excellent when compared with those of other N-doped porous carbons derived from other PBZ matrices.

A special glass system of the chemical composition (55 − x) B2O3–15Bi2O3–15SiO2–15TeO2–x CeO2, (x = 0, 5, 10, 15 and 20 mol%), was prepared by melting-annealing technique. XRD investigation was employed to identify the microstructure and confirmed the amorphous structure of these glasses. From the FTIR analysis, it can be assumed that CeO2 possesses a glass conditional former property. It is also assumed that the transformation of BO3 to BO4 groups with increasing of the CeO2 content caused a packing of the structure of the glass and increased its rigidity. This compactness of the structure increased the mechanical parameters such as density, ultrasonic velocity and elastic moduli. Also, both the glass transition temperature (Tg) and the optical band gap (Eopt.) show gradual increase in their values with increasing of CeO2.

In this work, nanoporous Cr2O3 was easily synthesized through the direct thermolysis of the as-prepared chromium-based metal-organic framework (MIL-101(Cr)) in air and used as a dopant to titanium alkali borosilicate glasses. The integration of octahedral unit of nanoparticles Cr2O3 in the network of titanium alkali borosilicate glasses, as deduced from FTIR enhanced the physical properties of the glasses by transforming the [BO3] into [BO4] structural units and consequently creating surplus bridging oxygens. The increase of the fraction N4 consolidates this hypothesis. The mentioned oxygens increased the number of bonds per unit volume, the density and decreased the molar volume of the glass network. The variations of these physical parameters as a function of Cr2O3 increased the ultrasonic velocities, the Debye temperature and the rigidity of the glasses on one hand and decrease the optical band gap on the other hand.

As the chalcogenide thin films have broad technological applications due to the ability of tuning their properties through composition change, lead addition has been used to tune the energy gap, refractive index, and non-linear optical parameters of Ge25As10Te65−xPbx thin films. The optical constants of Ge–As–Te thin films have been studied when introducing different contents of Pb. Tauc’s rule of the allowed indirect transitions was successfully used to describe the optical transitions of the Ge25As10Te65−xPbx (0 ≤ x ≤ 10 at. %) thin films. It was found that when increasing Pb content the optical band gap ( $$ E_{\text{g}}^{\text{opt}} $$ ) decreases whereas the index of refraction increases. The obtained behavior of $$ E_{\text{g}}^{\text{opt}} $$ was interpreted in terms of Mott and Davis model. The energy reliance of the index of refraction (n) shows a normal dispersion that may be explained using the single oscillator model. Applying such model allowed to estimate the static index of refraction (no) and the energies of both single oscillator (Eo) and dispersion (Ed). In addition, the non-linear optical parameters such as the third-order susceptibility (χ(3)) and nonlinear index of refraction ( $$ n_{2}^{*} $$ ) have been deduced from Eo, Ed and no values. Both χ(3) and $$ n_{2}^{*} $$ increase with increasing Pb content.

Theoretical insights of the ultrasonic relaxation process in PbO–WO3–TeO2 glasses were investigated according to a model related to the propagation of ultrasonic waves in active two-well potential. The energy transfer of the ultrasonic waves either longitudinal or transverse to the glass network can create two-well potential based on the oxygen atoms displacements. The parameters of the model such as the mutual potential energy, the loss-centers, the prolongation or shrinkage of the double-well system, deformation potential were affected with the concentrations of the PbO. The number of loss centers was correlated to the compositional dependence of the elastic moduli on PbO content. The results showed that the degree of prolongation or shrinkage of the double-well system is affected with the concentration of PbO.

This article is allocated to study optical characteristics of a-(Cu2ZnGe)50−xSe50+x, CZGSe, ( 0 ≤ x ≤ 20 at wt % ) films. The amorphous nature of films was affirmed via X-ray diffractograms. energy-dispersive X-ray spectroscopy confirmed the matching between selected compositional element percentages and those measured for all films. Many optical properties and parameters of CZGSe films were studied using UV–vis-INR spectroscopic transmission and reflection measurements. The envelope methods have been successfully applied on the measured transmission spectra according to Swanepoel technique, along with reflection spectra in accordance with Minkov method. Obtained results based on Swanepoel analysis are in excellent agreement with those inferred from Minkov method. A clear blueshift of the absorption edge was observed from 854 nm to 720 nm, in accordance with the increasing optical bandgap energy values from 1.456 eV to become 1.722 eV, as Se-content increases from 50 to 70 at wt%. The electronic transitions of (Cu2ZnGe)50−xSe50+x films arose from allowed indirect transitions. This observed energy gap increases was interpreted according to the Mott and Davies model. The absorption coefficient values have been estimated and discussed, it is found to be larger than 10−4 cm−1. All discussed parameters strongly depend on the Se-concentration. The bonding strength between the elements of samples strongly affects the optical properties.

Characterizations of the prepared pseudo penta-glass system 60 PbO – (40-x) SiO2 – x (0.1 Li2O – 0.86 B2O3 – 0.04 Dy2O3) with 0 ≤ x ≤ 30 mol% were performed in terms of the ultrasonic and spectroscopic techniques. The increase of (0.1 Li2O – 0.86 B2O3 – 0.04 Dy2O3) content causes borate structural variations such as the transformation of [BO3] to [BO4] structural units and enhancement of the compactness of the glasses. These physical parameters play an important role in modifying the mechanical and the optical properties of the lead silicate glasses. The improvement of the mechanical properties is indicated from the increment of the density, the ultrasonic velocities, the elastic moduli (experimentally determined and theoretically computed) and the glass transition temperature. The borate structural variations along with the presence of Dy2O3 decrease both the UV transmission and the optical energy gap, increase the refractive index and created several transitions at different wavelengths.

Boro-tellurite glass system with different concentrations of Bi2O3 had been prepared and characterized. The FTIR analysis indicated a glass former role of Bi2O3 that was deduced from the formation of [BiO3] structural units. These units transformed the structural units [TeO3] into [TeO4] and [BO3] into [BO4]. This process increased the environment of bridging oxygens that increased the density and decreased the molar volume of the glass structure. The increase of the ultrasonic velocities, the elastic moduli (experimentally determined and theoretically computed according to Makishima-Mackenzie model) with the addition of Bi2O3 was attributed to the increased compactness and rigidity. The increment coordination number increased the cross-link density and improved the glass transition temperature. The hyper-polarizability of Bi3+ due to the d-orbital contribution increased the crystallization peak and enhanced the thermal stability.

In this work, new nanoclay composites were prepared through in situ polymerization for reported conducting polyarylidenes based on cyclopentanone and cyclohexanone moieties in the main chain. Additionally, a novel conducting polymer (CP), based on cycloheptanone, was synthesized along with its nanoclays. The studied materials were characterized via Fourier transform infrared spectroscopy (FTIR), X-ray diffraction, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The main objective was to study the effect of nanoclay modification and ring size on CP solubility, thermal behavior, optical properties, and corrosion inhibition effects. The obtained results showed enhanced solubility and thermal stability of the nanocomposites compared to their original CPs. Moreover, all materials emitted efficiently in the solid state with luminescence enhancement and dependence on aggregation. Furthermore, these CPs and their nanoclays were checked as corrosion inhibitors against mild steel dissolution in acidic media. Cycloheptanone nanocomposites showed the highest inhibition efficiency (95.92%), confirming that the presence of nanoclays can enhance the CP’s ability to retard the corrosion by covering more surface area of the metal. This study presents ways to enhance the solubility, thermal stability, and corrosion inhibition efficiency of CPs using nanoclay modification. Additionally, these nanoclays may be used as solid-state luminescent materials and mixed inhibitors. Conducting polymers were synthesized via in situ polymerization, using nanoclay bentonite sodium and its modified form. The polymer nanoclay modified form showed enhanced solubility compared to the original polymers and improved thermal stability, along with higher corrosion inhibition efficiency and aggregation-induced emission with luminescence dependent on the aggregate structure.

In the present work, the coupled plasma theory (thermally and elasticity waves) was used to study the wave propagation of semiconducting sample through photothermal process. The coupled of the plasma, thermally, and elastic waves that photo-generated through intensity modulated laser beam and tightly focused has been considered to study an elastic homogeneous semiconducting medium with isotropic thermo-elastic properties. Laplace transformations were used to investigate analytically solutions in the transformed domain based on the approach of eigenvalue. Numerically calculations were carried out for silicon semiconductor sample. The results were graphical observed to show the influence the coupled wave of plasma, thermal, and elastic.

Recycling the solid wastes like cement dust and limestone dust and using in the manufacturing of glass and glass - ceramics are strongly needed. These glasses fabricated by melt-quench technique. The X-ray diffraction (XRD) patterns of all the studied samples confirmed the amorphous nature These glasses have been investigated for their physical properties using density and molar volume, structural properties using FTIR spectroscopy, optical properties using UV-Vis spectroscopy, thermal analysis and mechanical properties. The density, molar volume and refractive index vary with the concentration of CaO. The variations of various physical, structural, thermal analyses, mechanical and optical properties with the concentration of CaO in this glass system depict a strong structural influence of CaO. The ultrasonic velocity of these glasses has been decreased with addition of CaO, this decrease is connected to the decreasing the bonding strength between Calcium - oxygen are lower than the bond between silicon - oxygen (32-106 k cals).The elastic moduli of these glasses determined experimentally and calculated theoretically, according to Makishima–Mackenzie model decreased with increasing of CaO. This behavior may be related to changing the coordination number with an increasing of CaO and the decrease in the average force constant and crosslink density. The crystalline phase of the prepared glass ceramic is diopside with the chemical formula (Ca MgO6 Si) in all selected samples.

Chalcogenide glasses own high degree of disorder which is a significant parameter to improve the performance of thermoelectric materials. Here, we study the electrical and thermoelectric properties of vacuum deposited In x Se100- x ( ${x} = \textsf {6}$ , 12, 18, and 24) chalcogenide thin films in the temperature range from 300 to 450 K. The values of dc conductivity have been determined and were found to increase from $\textsf {0.029} \times \textsf {10}^{-\textsf {10}} \Omega ^{-\textsf {1}}\,\cdot \, \text{m}^{-\textsf {1}}$ ( ${x} = \textsf {6}$ ) to $173.546\times 10^{-\textsf {10}} \Omega ^{-\textsf {1}}\,\cdot \, \text{m}^{-\textsf {1}}$ ( ${x} = \textsf {24}$ ). Thin film samples for ${x} = \textsf {6}$ , 12, 18, and 24 have shown high values of the Seebeck coefficient. The obtained results for the dc conductivity and the Seebeck coefficient may lead to a high value of the power factor. Looking into the results, it is expected that ${x}= \textsf {6}$ , 12, 18, and 24 samples have high figure of merit and may be explored as new thermoelectric materials.

The density, the molar volume, the rigidity, the UV reflectance and the glass transition temperatures of the x TiO2 – 20Na2B4O7 – 30PbO – 20SiO2 – (30-x) Bi2O3 glass system were determined. These physical parameters were acquired by using the DTA, ultrasonic and UV techniques to explore the effect of TiO2. The replacement of Bi2O3 by TiO2 decreased these physical parameters, which suggested the glass modifier role of TiO2. This attitude can be attributed to the smaller ionic radii, the density and the polarizability of TiO2 than that of Bi2O3. Moreover, according to the FTIR, TiO2 created non-bridging oxygens in the network that decreased the bond strength of the glass system. The decreases of the rigidity, the glass transition temperature and the optical band gap are sensitive to the decrease of the bond strength and the created non-bridging oxygens in the lead alkali borosilicate network. The obtained results were discussed in relation to the role of TiO2 in the lead borosilicate glass system.

Binary As–Se glasses with different amounts of As content have been prepared and scanned with different heating rates (3 ≤ ψ ≤ 48 K min−1) over temperatures ranging from 300 to 450 K. Both the glass transition temperature (Tgl) and the temperature peak of crystallization (Tpc) increase as a function of As and/or the ψ values. A good correlation between Tgl and Tpc has been investigated. The observed increase in Tgl and Tpc by increasing the ψ values or as a function of As is well discussed in accordance with Lasocka’s relationship and using the average coordination number Acn, the viscosity at glass transition μ(Tgl) and the overall mean bond energy E. The glass transition Egl and crystallization activation energies (Egl and Epc) were determined based on the changes in Tgl and Tpc values due to the heating rate (ψ). The increase in the values of Egl and Epc with increasing the As content is expected due to the increase in Tgl and Tpc values. The kinetic exponent n and the crystal dimensionality m have been determined.

New glasses from harmful environmental waste like cement dust; limestone phosphate and sand were fabricated. The constructions of these sample investigation by FTIR, mechanical and optical properties. The density and refractive index of these glasses increases by increasing of SiO2 concentration. Longitudinal (vL), and share (vT) velocities increase with addition of silicon oxide. The elastic moduli values were showing increasing as an increasing of SiO2 concentration. The increase in elastic moduli may be connected to changing of the coordination number with an addition of SiO2 and the increase the bond strength, average force constant and the crosslink density. DTA of the investigated samples with exclusive SiO2 contents shows the increasing in Tg values. The molar volume and the optical band gab of these glasses decreases with increase of SiO2 expense on CaO.

Polyamides containing thieno[2,3-b]thiophene moiety were prepared via a simple polycondensation reaction of the diaminothieno[2,3-b]thiophene monomer 1a with different kinds of diacid chlorides (including oxalyl, adipoyl, sebacoyl, isophthaloyl, terephthaloyl, 4,4′-azodibenzoyl, 3,3′-azodibenzoyl, p-phenylene diacryloyl) in the presence of LiCl and NMP as a solvent through lowtemperature solution polycondensation. The chemical structures of model compound and synthesized polyamides were confirmed by FTIR, nuclear magnetic resonance spectroscopy (including 1H-NMR and 13C-NMR) and elemental analysis. In addition, the thermal stability, crystallinity structure and surface morphology of synthesized polyamides were characterized via thermogravametric analysis (TGA), wide-angle X-ray diffraction analysis (WAXD) and scanning electron microscopy (SEM). Also, the corrosion inhibition behavior of selected examples of polyamides was investigated; the inhibitive effect of the investigated polymers for carbon steel in 1.0 mol·L−1 HCl was studied using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) methods. PDP results displayed that the polyamides containing thieno[2,3-b]thiophene moiety can be as mixed-type inhibitors. The inhibition efficiency (P, %) was found to be in the range from 67.13% to 96.01%. There is an increase in P by the synthesized polymers in comparison to the starting monomer. The adsorption of these polymers was found to obey Langmuir adsorption isotherm.

Pseudo quaternary Na2B4O7–SiO2–MoO3–Dy2O3 glasses with various concentrations of Dy2O3 were synthesized and characterized by ultrasound, DTA and X-ray diffraction (XRD). It was found that, the density, the molar volume and the elastic moduli increased while the ultrasonic velocities and the packing density decreased with increasing of Dy2O3 concentration. The lower values of the radii and the bond length of B2O3, compared to those of Dy2O3, decreased the interatomic forces between the reactant glass forming cations and oxygens inside the glassy network. Accordingly, this will increase the molar volume and in the same time will decrease the average cross-link density, the ultrasonic velocities, the glass transition temperature and the thermal stability. Also, this may result in a high density glass sample which will increase the elastic moduli. Based on Lasocka's model, a good correlation between the temperature of both glass transition ( T gl ) and crystallization peak ( T pc ) was observed.