Differential Thermal Analysis Research Articles

Multifaceted Analysis of L-Alanine-Doped Creatininium Benzene Sulphonate Single Crystals for Optical Modulation Application

Creatininium Benzene Sulphonate (CBS) and L-Alanine-doped Creatininium Benzene Sulphonate (ACBS) single crystals were grown using the slow evaporation technique. Xpert HighScore software was utilized to determine lattice parameters including Full Width at Half Maximum (FWHM), crystallite size, and lattice strain. Fourier transform infrared spectroscopy was used to identify the functional groups present in the samples. The thermal properties of CBS and ACBS crystals were analyzed using Thermogravimetric and Differential Thermal Analysis. Optical properties including optical conductivity, extinction coefficient, and refractive index were measured using UV-Vis spectroscopy. The mechanical characteristics of both samples were studied using Vicker’s microhardness testing, and the dielectric response was recorded for various frequencies. The second harmonic generation values of samples were compared to those of potassium dihydrogen phosphate. Overall, CBS and ACBS crystals demonstrate promising characteristics as sustainable materials for optical modulation. Incorporating amino acids, such as L-Alanine, enhances the photoconductive properties of the crystals by improving charge carrier mobility and reducing recombination rates, resulting in more efficient optical modulation. This study explores the impact of doping single crystals with amino acids on their optoelectronic and dielectric properties for potential applications in optical modulation devices. Specifically, this research investigates the role of L-Alanine, a zwitterionic amino acid, in enhancing the performance of CBS single crystals, with the aim of optimizing their structural, thermal, optical, and mechanical properties for optical modulation. These findings highlight the potential of amino acid-doped single crystals in advancing optical devices, driving innovations in optoelectronics and photonics.

Mongrel synthesis of tin (IV) based 3-aminopyridine with hydrogen halides: Structural, optical, thermal analysis, DFT, Hirshfeld surface analysis and antibacterial investigations

The novel organic-inorganic hybrid materials (C5H7N4)2 [SnCl6] 2- (1) and (C5H7N4)2 [SnBr6]2-(2) have been synthesized and characterized by single-crystal X-ray diffraction at room temperature. Both compounds demonstrate the crystal system was triclinic with Pī space group. Hirshfeld surface analysis investigate the intermolecular interactions and crystal packing derived by single-crystal XRD data reveals the closer contacts associated with strong interactions. Infrared spectrum of both compounds shows the NH stretching band at 3396 cm−1 which indicates a protonated amine group. The product crystals optical characteristics were inspected using UV–visible and photoluminescence spectroscopy. The thermal characteristics were evaluated simultaneously using thermogravimetric (TG) and differential thermal analysis. Tin formal oxidation state was determined as +4 through bond valence sum calculations and CSM shows the ideal octahedral geometry of the anions. DFT calculations utilizing the B3LYP method with the LanL2DZ basis set provide optimized geometries and molecular electrostatic potential maps. We explored the energy difference between (HOMO) and (LUMO) orbitals to understand molecular electrical transport capabilities. The biological activity of the investigated compounds are examined against pathogens which indicates efficacy against bacterial strains.

High-Yield Synthesis Route, Post-Synthesis Treatment, and Insights into the Photoluminescence and Magnetic Properties of Tricopper(I) Melaminate Cu3(C3N6H3).

A novel and more efficient synthesis of Cu3(C3N6H3) is presented through a salt-metathesis reaction using copper(I) chloride and sodium hydrogen cyanamide. This synthesis yields a melaminate trianion through the cyclotrimerization of (HNCN)- ions, offering an alternative route to the deprotonation of melamine for synthesizing melaminate. The reaction is analyzed via differential thermal analysis. After the unconventional formation of this MOF-like structure by solid-state reaction, this material still requires treatment via solvent exchange and vacuum drying due to the presence of a host molecule inside the channels of the structure. The process and the impact of the treatment of Cu3(C3N6H3) on its XRD pattern are thoroughly discussed. Additionally, results from stability, NMR and infrared spectroscopy, and thermogravimetric analysis. Finally, photoluminescence and magnetic studies are conducted to evaluate their potential as a functional material.

Binding properties of synthesized CS glasses activated by alkaline components

The paper presents the synthesis and evaluation of hydration and binding properties of individual minerals with glass-like structures in silicate systems, most often found in technogenic materials based on phosphorus and blast furnace slags. This work aims to determine the optimum composition of CS glasses to obtain binders with given properties, the hydration of glasses of different silicate and aluminosilicate compositions in the presence of solutions of soda, sodium hydroxide, and sodium metasilicate was investigated. The results of X-ray phase and differential-thermal analysis, and infrared spectrum are given, and the hydration structure of the calcium oxide-silicon oxide-alkali component system has been studied. The analysis of hydrate neoplasms of the studied binding systems shows that the most optimal conditions for the synthesis of stone strength with stable physical and mechanical properties are created in the presence of gel-like phase reinforced by hydrosilicates and hydroaluminosilicates of alkaline and alkaline-alkaline-earth composition, characterized by fiber-like structure and possessing the ability to epitaxial fusion with each other, as well as gel-like phase, which they reinforce.

Obtaining granular adsorbents based on biopolymers and clay minerals

The development of granular, low-cost adsorbents represents an important environmental challenge. Natural clay minerals show promise in this area, as they exhibit adsorption capacity a range of pollutants. Nevertheless, the high dispersion of aluminosilicates limits their widespread use. To enhance the processability of these materials, they are subjected to granulation using natural biopolymers, such as sodium alginates. Concurrently, the adsorption capacity of the granules can be increased by the application of modifiers to the surface of natural silicates, in particular iron oxyhydroxides, which are efficacious in the removal of heavy metals from water. The aim of this study is to obtain granular adsorbents based on saponite and biopolymer that are stable in water and capable of removing heavy metal ions from the water environment. The rheological behavior of the suspensions was investigated in order to ascertain the optimal conditions for high-quality granulation. The phase composition of the modified saponite was determined by X-ray diffraction analysis. The structural-sorption characteristics of the samples were investigated using the method of low-temperature nitrogen adsorption-desorption, and their thermal properties were studied by differential thermal and thermal gravimetric analyses. The present study demonstrates that the viscosity of saponite and sodium alginate-based suspensions with varying mass ratios is dependent on the clay mineral content of the mixture, at a fixed polymer quantity. The conditions for granulation were determined, and it was established that the stability of the granules in the aqueous medium is influenced by the quantity of sodium alginate incorporated into the mixture. It was established that the specific surface area of the modified sample decreases during the granulation process. This value is 109 m2/g, which is less than the 173 m2/g that observed for the powdered adsorbent. The processes and phase transformations occurring in granular materials during heating were studied. As a result of the study of the rheological characteristics of suspensions based on saponite and sodium alginate, it was found that these systems are thixotropic. It was also discovered that the stability of the granules in an aqueous medium is significantly affected by the amount of sodium alginate added to the suspension. The potential applications of the obtained adsorbents in the purification of water from heavy metal ion contamination are shown.

EVALUATION OF TECHNOLOGICAL PLASTICITY OF HIGH BORON CORROSION-RESISTANT STEEL DURING HOT DEFORMATION OF PIPES USED FOR SPENT NUCLEAR FUEL STORAGE

Statement of the problem. The sustainable development of the global nuclear power industry in the future depends on how effectively the problems of radiation safety and nuclear proliferation are addressed. Such problems occur, among other things, at the final stage of the nuclear fuel cycle – spent fuel management. This task is currently on the agenda of both the international community and national governments of countries that develop or intend to develop nuclear energy [1−3]. Today, in connection with ensuring the safety of nuclear energy, boron-containing steels are widely used in the world practice as a material for biological protection and for the manufacture of special equipment parts. This is due to the fact that the B10 isotope in steels provides neutron capture [4]. Hexagonal pipes made of high-boron steel were needed to shield the support cover of the compacted spent fuel storage facility at nuclear power plants. Corrosion-resistant steels alloyed with boron are widely used in the nuclear power industry due to their special nuclear properties. During the operation of nuclear power plants, fuel assemblies that have served their useful life must be stored in special storage facilities using containers – hexagonal tubes made of 04Сr14Ti3B2V steel. To reduce costs during in the construction and operation of NPPs, part of the spent nuclear fuel management should be performed at Ukrainian enterprises. This will provide a significant import substitution effect. To manufacture hexagonal tubes from 04Сr14Ti3B2V steel according to the ingot-hot deformation-profiling-heat treatment scheme, it is necessary to develop the parameters of hot deformation and subsequent technological operations. The use of these pipes in compacted spent fuel storage facilities of NPPs will allow to increase the storage capacity by 2 times, which will give a significant national economic effect Material and methods of research. Material used for the study was steel 04Сr14Ti3B2V (CS-82), smelted using two variants (vacuum-induction – “VI” and vacuum-induction followed by vacuum-arc remelting – (“VD”). Steel grade 04Сr14Ti3B2V belongs to high-alloy, corrosion-resistant ferritic steels with a high boron content of up to 2 %. The method of differential thermal analysis was used to study the phase transformation temperatures in the steel. X-ray diffraction and micro-X-ray spectral analysis were used to assess the phase state. The steel samples were tested for weldability After cooling, the welded samples were subjected to X-ray transmission [5]. Hot twisting tests and mechanical tests at high temperatures were also performed. The macro- and microstructure of the metal was studied. Results. The macro- and microstructure of steel was evaluated depending on the smelting method. The phase composition of the steel was studied. The study of the plastic properties of steel ChS-82 by means of penetration and hot twisting tests showed that the temperature range of maximum plasticity is in a wide range (from 1 025 to 1 150 0C) with a rather low resistance to deformation. During hot deformation in the temperature range of 1 175 0C and above, metal fracture was observed along the grain boundaries at the melting points of the Cr−Fe−B boride phase. The optimal temperature range for hot deformation of steel ChS-82 is 1 000−1 050 ⁰С. Scientific novelty. For corrosion-resistant high boron steel used for spent nuclear fuel storage, the temperature range of hot deformation was selected and the structural and phase composition was estimated, which will allow deforming the metal on the piercing mill and manufacturing pipes.

Coal-derived char as new sand replacement material in cement mortars: A comprehensive experimental study

Coal char is a coal-derived product produced by pyrolysis of char, which has valuable applications in the production of building materials. This paper presents the use of coal char in developing coal char-based cement mortar. Coal char is used to replace the sand, partially, at different proportions in cement mortar, and the change in properties is studied. Four cement types are used in the initial study, and one is selected for a detailed study based on the water retention, density, and compressive strength of the mortar. The properties of coal char-based mortar for the selected cement are comprehensively evaluated in terms of flow, water retention, air content, density, compressive strength, flexural strength, porosity, water absorption, drying shrinkage, thermal conductivity, thermogravimetric and differential thermal analysis, and scanning electron microscopy. The addition of coal char at an optimum sand replacement content of 5 % increases the compressive strength of mortar by 17.55 % and the flexural strength by 17.57 %, compared to conventional cement mortar. The thermal conductivity reduces by a maximum of 20 %, compared to traditional cement mortar. This paper also presents a study to compare the addition of coal char and commercial biochar on the properties of masonry cement mortar. The compressive strength of mortar with coal char is 44.39 % greater than that of mortar with the same content of biochar. The addition of coal char as a new sand replacement material shows good potential in improving the engineering properties of mortar.

Modification of Sulfur Cake—Waste from Sulfuric Acid Production

In the production of sulfuric acid, sulfur cake—a waste product of the sulfur purification process—is formed in large quantities, which requires its disposal and use. For its use in composite materials, modification is necessary to convert sulfur into a polymer form. The aim of the study was to develop a method for modifying sulfur cake—a waste product of sulfuric acid production—for its disposal. Available reagents—styrene, glycerol, and oleic acid—were tested as modifiers in the work. The sample compositions consisted of 100% sulfur cake (no. 1) and its mixtures: 97% sulfur cake + 3% styrene (no. 2), 97% sulfur cake + 3% glycerol (no. 3), 97% sulfur cake + 3% oleic acid (no. 4), 95% sulfur cake + 3% styrene, 1% glycerol, and 1% oleic acid (no. 5). Modification of sulfur cake was carried out at a temperature of 140 °C for 30 min. The composition, crystal structure, and thermal properties of the samples of the original and modified sulfur cake were studied using X-ray phase and X-ray structural analyses, IR spectroscopy, differential scanning calorimetry, differential thermal and thermogravimetric analysis. The optimal modifier for sulfur cake was a mixture of styrene, glycerol, and oleic acid, which led to the formation of acetal (polyoxymethylene) and an improvement in the structure due to a decrease in the content of impurities. Modification of sulfur cake with styrene resulted in the appearance of a CAr–S bond band at 571 cm−1, and modification with oleic acid a C–S band in the region of 694 cm−1 in the IR spectra. The results of differential scanning calorimetric analysis showed an increase in the heat of fusion of sulfur by 12.45 J/g in the samples of sulfur cake modified with glycerol and styrene. Modification of sulfur cake with oleic acid and a mixture of reagents resulted in the appearance of a third peak with maxima at 244.2 and 264.0 °C, which demonstrated a significant effect of the indicated additives on the thermal behavior of the sulfur cake. Proposed schemes for modifying sulfur cake with styrene and oleic acid are presented.

Adsorption of Methylene Blue and Eriochrome Black T onto Pinecone Powders (Pinus nigra Arn.): Equilibrium, Kinetics, and Thermodynamic Studies

In this study, methylene blue (MB) and eriochrome black T (EBT) dyes were removed with the waste Pinus nigra Arn. powders from Anatolian black pinecone (PC-PnA) within the framework of sustainability. UV–Vis spectroscopy, X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray (EDX), fourier transform infrared spectroscopy (FTIR), thermogravimetry–differential thermal analysis (TGA-DTA), Brunauer–Emmett–Teller (BET) surface area, and point of zero charge (pHpzc) analyses were performed for the characterization of PC-PnAs. The effects of pH, amount of adsorbent, time, initial concentration and temperature were determined by batch adsorption experiments. Four kinetic and isotherm models were examined, and error function tests were used for the most suitable model. According to this, the average pore diameters, mass losses at 103.9 and 721.6 °C and pHpzc values of PC-PnAs were found as 61.661 Å, 5.9%, 30%, and 5.77, respectively. Additionally, the most suitable kinetic and isotherm models for the removal of both dyes were Langmuir and pseudo-second-order. The maximum removal efficiencies (qmax) for MB and EBT dyes was calculated as 91.46 and 15.85 mg/g, respectively and the adsorption process was found to be endothermic. As a result, PC-PnA particles can be used as an alternative sorbent for the removal of MB and EBT dyes.

Polymer Boron-Containing Composite for Protecting Astronauts of Manned Orbital Stations from Secondary Neutron Radiation

This article considers the prospects of using heat-resistant polyimide boron-containing composites to protect astronauts of manned orbital stations from secondary neutron radiation. Variant calculations are performed regarding neutron and gamma-quanta flux distributions in a polyimide composite material with different boron content used to reduce capture radiation. The dependences of spatial distributions of thermal neutron flux density and the gamma-quanta dose rate in a polyimide composite layer with a boron content of 0 to 5% are obtained. An experimental assessment of the energy distribution of neutron and gamma radiation behind the protective polyimide composite is carried out. The introduction of boron atoms in an amount of 3.0 wt.% shows the absence of bursts of secondary gamma radiation energy in the composite, which is due to the high cross-section of thermal neutron absorption by boron atoms. As a result, with a material layer thickness of 3–10 cm, the gamma-quanta dose rate decreases by 2–3 times. The differential thermal analysis method showed that the upper limit of the working temperature of the polyimide composite is 500 °C. The polyimide matrix filled with boron atoms can find effective application in the development of new radiation-protective polymer materials used in manned orbital stations.

Phase equilibrium investigations and thermodynamic modelling of the ZrO2-HfO2-Ta2O5 system

The phase equilibria in the ZrO2-HfO2-Ta2O5 system were studied at 1673 K and 1873 K by equilibration technique and in the temperature range up to 2473 K by differential thermal analysis (DTA). The phase and chemical composition of the samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX). Melting relations were studied by DTA followed by microstructural investigation by SEM/EDX. The composition dependence of the eutectic and peritectic temperatures was shown. The heat capacity of the (Zr,Hf)6Ta2O17 compound with different compositions was measured by differential scanning calorimetry (DSC) in three temperature ranges from 100 K to 230 K, from 220 K to 570 K, and from 330 K to 1295 K. Based on the obtained results and our previous thermodynamic descriptions, a database for the ternary ZrO2-HfO2-Ta2O5 system using the CALPHAD approach was created.

Beam‐Generated Sample Evolution to Emphasize Spatial Inhomogeneities: The Example of HPO42−‐Containing Amorphous Calcium Phosphate

ABSTRACTAmorphous calcium phosphates (ACPs) represent a family of bioactive compounds particularly relevant to bone regeneration. However, due to their intrinsic metastability, their processing into 3D‐shaped materials cannot be undergone by conventional sintering methods and requires cold sintering approaches. Also, their microstructure and local compositional changes still have to be explored in detail. To this aim, spectroscopy techniques are particularly appealing to probe local chemical environments at the microscale. Concerning ACPs, one question regards the distribution of (hydrogenated) phosphate species, as they may lead to various evolutionary trends. In this contribution, we purposely exploited the laser–beam interaction through Raman mapping to trigger the in situ HPO42−‐to‐P2O74− transformation. Analysis by a multivariate approach allowed us to spot P2O74− clusters resulting from HPO42−‐rich initial domains. Moreover, a blue shift of the ν1PO43− band was noticed in the close vicinity of these clusters, thus evidencing a local evolution of the chemical composition of the ACP. These results, corroborated by differential thermal analysis, demonstrate the relevance of using the laser–sample interaction through local heating to probe the spatial evolution induced, in our case, by an ultrafast compaction process. Comparison of outcomes obtained using two different laser/power strategies finally evidenced the need to adapt the Raman analytical conditions to the behavior of the metastable material to analyze.

Differential thermal analysis of thermostable coating based on local raw materials

Differential thermal analysis of thermostable coating based on local raw materials

A facile synthesis procedure for Engelhard titanosilicate (ETS-4) and its Cs+ and Sr2+ ion exchange properties

This manuscript reports an environmentally benign method for the synthesis of Engelhard titanosilicate (ETS-4) using titanium isopropoxide or anatase as titanium source and citric acid as complexing agent. Slow release of Ti from the hydroxide or oxide precursors through the citric acid complex plays crucial role in formation of titanosilicate. Characterizations of the prepared material were carried out by powder X-ray diffraction (XRD), Scanning Electron Microscope – Energy Dispersive X-ray spectroscopy (SEM-EDS), Thermogravimetric – Differential Thermal Analysis (TG-DTA) and ion exchange studies. Caesium and strontium exchange capacities of the synthesised ETS-4 were found to be 220 mg/g and 76.2 mg/g, respectively. The saturation exchange equilibrium was attained within 60 min.

Effect of sintering behavior and phase evolution on glass-ceramics entirely derived from ferrochrome slag and fluorite tailings

The recycling of solid waste is widely regarded as the one of the most crucial issues of sustainability. This is particularly evident in the industrial sector, where the production of slags is huge and their handling presents a significant challenge. In this study, solid wastes from the industrial sector, namely ferrochrome slag (Fs) and fluorite tailings (Ft), were employed for the preparation of glass-ceramics by the sintering method. Three glasses were prepared by using the melt-quenching method, with a weight ratio of 60∼70 % Fs and 40∼30 % Ft (designated S30, S35, and S40, where the higher number indicates a greater Fs content). The sintering and crystallization behaviors of these glasses were characterized by hot-stage microscopy (HSM) and differential thermal analysis (DTA). It was observed that S40 glass exhibited a weak sintering capacity in comparison to that of S30 and S35 glass, which can be attributed to the robust crystallization propensity of S40 glass. The coarser glass frits were subjected to sintering experiments at varying temperatures, which demonstrates that the predominant crystalline phase is augite and that Cr2O3 remains present in all sintered samples. Besides, a transition of the Cr2O3 crystal into uvarovite was observed in S40 glass sintered at 1050 °C. The sintering time controlling experiment demonstrated that both wollastonite and the Ca-rich flow formed during sintering are vital for the formation of uvarovite. The formation of uvarovite can enhance the hardness of GCs. All GCs samples sintered at 1050 °C and 1120 °C exhibit comparable mechanical performance.

Crystal Structure, Microstructure, and Dielectric and Electrical Properties of Ceramic Material Prepared Using Volcanic Ash

In the present work, the electrical and dielectric properties of ceramic samples prepared from volcanic ash were investigated. For this purpose, ceramic samples were prepared using milled volcanic ash with a binder material at a sintering temperature of 950 °C for 2 h. The chemical content of the milled volcanic ash was investigated using XRF. Differential thermal analysis and thermogravimetry were performed to determine the firing conditions. The crystalline phases and microstructures of the ceramic samples were investigated using XRD and SEM, respectively. Finally, the electrical and dielectric properties of the obtained samples were evaluated at a frequency ranging from 1 × 102 to 4 × 106 Hz and temperatures ranging from room temperature to 800 °C. The XRD results revealed that the ceramic samples contained three main phases: albite, hematite, and augite. Moreover, the microstructures of the samples exhibited a large crystal size with a dense surface. The conductivities and dielectric constants of the samples remained stable up to 500 °C. The real and imaginary parts of the dielectric constant decreased with an increase in frequency and increased with an increase in temperature. The results indicated that ceramics based on volcanic ash are promising for use in technological applications such as high-voltage power insulators.

Analyzing cold hardiness (Based on DTA) of one-year-old branches of peaches.

In this study, we conducted a low-temperature exothermic (LTE) investigation on 1-year-old (1a) branches of sixteen peach cultivars through a differential thermal analysis (DTA) procedure. We used a three-point approach to determine the lethal injury temperature (LT-I) of the xylem, the LTE correlation indexes, and the subordinate function value method were applied to compare cold hardiness of sixteen peach varieties. The results showed that the slope of the LT-I for the xylem of sixteen peach cultivars was different, and the LTE indexes were significantly different. Among all the studied varieties, the cold hardiness was strongest in Donghe No.1, followed by Wangjiazhuangmaotao No.2 and Hunchun. Qiuyan and Yanhong are second, and belong to the cold-resistant type; Qiuyi, Okubo, Zhongnongjinhui, and Chunmei, exhibited medium cold hardiness. Zhongtaohongyu, Spring snow, Yufei, and Zhongyou No.8 varieties exhibited low hardiness; while the 21st century, Golden Honey No. 1 and Zhonghuashoutao have the worst cold hardiness and are the weakest cold-hardiness types. In addition, the injury degrees of xylem from LT-I analysis were significantly related to the browning rates (BR) and electrolytic leakage (EI) from traditional low temperature freezing analysis. It is demonstrated that the LTE analysis is a simple, accurate, and practical method for identifying the cold hardiness of 1a branches of peach.

Synthesis and characterization of nickel and molybdenum catalysts supported on alumina derived from bauxite

In this study, a natural ore (bauxite), which is characterized by its high content of various aluminum minerals, such as gypsite, , bohmite, and diaspore, AlO(OH), was used to obtain alumina ( ), which was used as a support for the catalyst. The components of the ore were studied using multiple techniques, such as The X-ray energy dispersion (EDX) technique, X-ray diffraction (XRD) and X-ray fluorescence (XRF) technology. Then, undesirable components that negatively affect the behavior of the prepared catalyst were removed, such as carbonates, iron, and amorphous silica, and then aluminum oxide (alumina) was prepared from the ore using a series of chemical treatments. Then the mixed catalyst consisting of (nickel/molybdenum) carried on alumina was prepared, its properties were studied, and its components were identified by measuring energy dispersion with X-rays (EDX) and ensuring the extent of its thermal stability by conducting a thermal analysis measurement. Gravimetric analysis (TGA), differential thermal analysis (DTA), measurement of the surface area of ​​the prepared catalyst (BET), scanning electron microscope (SEM) measurement, as well as X-ray diffraction (XRD) and X-ray fluorescence (XRF) measurements to identify the percentages of metals, and then estimating the percentage of these elements in their oxide form. KEY WORDS: Catalyst, Bauxite, Nickel, Molybdenum Bull. Chem. Soc. Ethiop. 2024, 38(6), 1715-1724. DOI: https://dx.doi.org/10.4314/bcse.v38i6.17

Synthesis and structural characterization of new chitosan-thiamine hydrochloride molecular complexes

Chitosan is one of the natural cationic polymers used for drug delivery due to its unique properties as an antimicrobial and antioxidant agent. In this work, three new molecular complexes were obtained by mechanically grinding a mixture of chitosan and thiamine hydrochloride in weight ratios of 4:1, 3:2, and 1:1, with a few drops of acetic acid and sodium citrate solutions. Complementary analyses, including X-ray powder diffraction, differential thermal analyses, thermogravimetric analyses, Fourier transform infrared spectroscopy, and CP/MAS 13C NMR, were performed to characterize the new molecular complexes. X-ray diffraction revealed the transformation of chitosan from a semi-crystalline to an amorphous state after mechanochemical grinding. Infrared spectroscopy showed changes in the vibrations of the functional groups CO, OH, and NH in the structure of the developed compounds, indicating the interconnection of the components. Solid-state nuclear magnetic resonance spectroscopy recorded shifts of the resonance lines present in the ball-milled samples, compared to the initial compounds, along with the appearance of new lines, supporting the formation of chitosan-thiamine hydrochloride complexes. Thermal analyses confirmed the successful development of new molecular complexes by the appearance of two new exothermic signals at lower temperatures than those observed for chitosan.

Structural, thermal, and radiation shielding properties of B2O3-TeO2-Bi2O3-CdO-Tm2O3 glasses: The role of Tm2O3

This study presents a detailed investigation into the structural, thermal, and radiation shielding properties of a new glass composition, labeled as (50-x)B2O3 + 30TeO2 + 10Bi2O3 + 10CdO + x Tm2O3 (where x = 0, 1, 2, 3, 4, 5 mol %). Various radiation shielding parameters such as mass attenuation coefficient, linear attenuation coefficient, half-value layer, mean free path, effective atomic number, and absorbed equivalent dose rates for neutrons were determined through experimental measurements. The study also employed theoretical calculations to assess the exposure buildup factor and effective removal cross-section for neutrons. Additionally, the SRIM program was utilized to investigate mass stopping power and projected range for proton and alpha particles. The structural characteristics of the glasses were analyzed using XRD and FT-IR, while thermal properties were examined through Differential Thermal Analysis (DTA). FTIR analysis revealed distinctive bands corresponding to Bi—O, B—O—B, and Te—O bonds. Glass transition temperatures (Tg) increased with Tm2O3 content, ranging from 422 °C to 444 °C. The radiation shielding properties of bismuth boro-tellurite glasses showed that a dose of 1.2025 μSv/h emitted from a fast neutron source was absorbed by 35.1574 % in pure glass and 40.0391 % in glass doped with 5 mol% Tm2O3. Incorporating Tm2O3 into the glass matrix significantly improved the shielding and thermal properties, thus enhancing their potential for advanced high-energy radiation absorption. This investigation contributes to a deeper understanding of how Tm2O3 enhances the structural and thermal attributes of these glasses, positioning them as promising materials for radiation shielding applications.