Differential Scanning Calorimetry Techniques Research Articles

Thermal study of APNIMMO/CL-20 based propellants fabricated by 3D printing

Energetic photocurable binder has been developed to improve the energy content of 3D printed propellants. Thermal decomposition study is a significant part for evaluating novel binders and relevant propellants. In this paper, acrylate-terminated poly-3-nitratomethyl-3-methyloxetane (APNIMMO) and a series of formulas containing 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) were prepared by the stereolithography (SLA) printing. The thermal performance and decomposition kinetics were investigated by means of the nonisothermal DSC (differential scanning calorimetry) techniques. Additionally, simultaneous DSC-FTIR were employed to corroborate the thermal analysis results. The compatibility of the various admixtures was confirmed through an additional kinetic study for which the Arrhenius parameters were computed by different isoconversional Kissinger method and modified Kissinger-Akahira-Sunose (KAS) method. The decomposition products were also detected by in-situ DSC-MS-FTIR. The obtained results from the different techniques are presented and discussed.

The impact of the thermal annealing conditions on the structural properties of polylactic acid fibers.

Polylactic acid (PLA) is a prominent biomaterial for plentiful applications in medicine and industry. The main goal of using this new material is replacing polymers based on petrochemical. Different thermal and structural properties of PLA fibers were studied after the thermal treatment using two different conditions (taut and free ends). Different techniques were used to study the effect of the thermal treatment conditions on the crystallinity and molecular orientations for PLA fibers such as differential scanning calorimetry technique, X-ray diffraction technique, and polarized light microscopy. The impact of the thermal annealing treatment on both the crystallinity and crystalline orientation was calculated. In case of taut ends thermal annealing treatment method, the measured parameters were higher than the case of free ends thermal annealing condition. The oriented segment relaxation due to the thermal annealing results an increase in the crystallinity values, but it does not indicate that the molecular orientation will be high. Results showed that the orientation of crystal and crystallinity was improved after thermal treatment. The taut conditions of annealing show significant improvement of crystallinity than free conditions.

Phase transition characterization in sprouted quinoa flour (Chenopodium quinoa Willd.) variety Pasankalla

The thermal characteristics of phase transition in the field of food have significantly influenced consequently have attracted interest in his studies in different types of food products. Quinoa presents important nutritional sources, which facilitate its preparation of different processed foods. The objective of the research was to characterize the phase transition of germinated quinoa flour variety pasankalla. The analysis was performed using the differential scanning calorimetry (DSC) and thermogravimetric (TGA) technique. The results show that quinoa presents a thermal transition and enthalpy of high gelatinization, just as thermal modifications due to the effect of heat and humidity change the physicochemical properties of its starches.

Liposomes as nonspecific nanocarriers for 5-Fluorouracil in the presence of cyclodextrins

5-Fluorouracil (5-FU) is one of anticancer drugs with broad activity. Due to its severe side effects, recent studies concentrate on new ways of directed 5-FU delivery and its release in ill tissue. One of selective carriers could be cyclodextrins and liposomes. The combination of novel methods, leading to formation of inclusion complexes (IC) between host molecule of β-cyclodextrin (β-CD) or 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) and 5-FU guest and its subsequent encapsulation in dipalmitoylphosphatidylcholine (DPPC) liposomes is studied experimentally in the present work. Several methods are applied to proof the encapsulation of the analysed drug and its release over time at 37 and 41 °C. The 5-FU release from complex of liposomal form of 5-fluorouracil and β-cyclodextrin (L[DPPC/5-FU]:β-CD) and complex of liposomal form of 5-fluorouracil and (2-hydroxypropyl)-β-cyclodextrin (L[DPPC/5-FU]:HP-β-CD) was followed using UV–Vis and fluorescence spectroscopy, proton nuclear magnetic resonance (1H NMR) and differential scanning calorimetry (DSC) techniques. The electronic and NMR spectra analysis were additionally supported by molecular modeling, including prediction of spectral changes in vacuum and in water using density functional theory (DFT-B3LYP-D3). From the observed changes the fastest release from liposomes (within 1 h) was observed for the 5-FU complexes with HP-β-cyclodextrin at 41 °C.

Non-isothermal cold crystallization, melting, and moisture barrier properties of silver-loaded kaolinite filled poly(lactic acid) films

Silver-loaded kaolinite (AgKaol), an antibacterial agent along with a barrier enhancer, was incorporated into poly(lactic acid) (PLA), poly(butylene adipate-co-terephthalate) (PBAT) and tetrabutyltitanate (TBT) blend resulting in the formation of polymer composite. The introduction of AgKaol could improve the barrier and the crystallization properties of PLA/PBAT/TBT blend. The barrier property of composite polymer was investigated by water vapor permeability (WVP) to study the influence of AgKaol content (0.0, 1.0, 2.0, 3.0 and 4.0 phr) in polymer matrix. The values of WVP decreased with increasing AgKaol content and amount of crystallite in PLA composite. The cold crystallization property of this PLA/PBAT/TBT composited with 0.0, 2.0 and 4.0 phr of AgKaol was completely investigated by the non-isothermal differential scanning calorimetry (DSC) technique. From the non-isothermal DSC analysis, the crystallization rates (dX(T)/dt) of PLA composite increased with increasing of the heating rate and AgKaol content. The Avrami, Ozawa and Liu models were applied to describe the non-isothermal crystallization kinetics and determine crystallization parameters for PLA/PBAT/TBT/AgKaol composite. The crystallization mechanism of PLA/PBAT/TBT/AgKaol composite was proposed thorough the nucleation and three dimension growths. The activation energies of crystallization (Ea) were determined by the Kissinger-Akahira-Sunose (KAS) isoconversional method. The determined Ea for the crystallizations of PLA/PBAT/TBT with 4.0 phr of AgKaol were lower than 2.0 and 0.0 phr, respectively. Polarized optical microscopy (POM) showed more and larger spherulites with a nanocrystal structure of PLA/PBAT/TBT/AgKaol composite than neat PLA. The nucleating effect of AgKaol on PLA/PBAT/TBT blend might be useful for preparation of PLA composite as a gas barrier protection material in the future. Corresponding to the melt flow index (MFI) results, PLA composites could produce as a film with promising antibacterial packaging due to silver nanoparticles in AgKaol.

Magnetic Properties of Novel Layered Disulfides CuCr0.99Ln0.01S2 (Ln = La…Lu).

The comprehensive study of the lanthanide-doped solid solutions CuCr0.99Ln0.01S2 (Ln = La…Lu) magnetic properties was carried out using static magnetochemistry and differential scanning calorimetry techniques. It was shown that magnetic properties of CuCr0.99Ln0.01S2 are significantly affected by the magnetic properties of the lanthanide ion. The magnetic susceptibility and the effective magnetic moment were found to deviate from the Curie-Weiss law in the temperature 90 K below and 50 K above the order-disorder transition at 695 K. The observed behavior of the temperature dependence of the effective magnetic moment in the order-disorder transition temperature region was described as a result of copper atoms redistribution over different types of the crystallographic sites.

Catalytic effect of [trans-Cu(μ-OH)(μ-dmpz)]6 on the thermal decomposition of ammonium perchlorate

Spatial race under low oxygen conditions requires solid mild propellants to be used. Therefore, we study the catalytic effect of the previously reported [trans-Cu(μ-OH)(μ-dmpz)]6 complex on the thermal decomposition of ammonium perchlorate by a differential scanning calorimetry (DSC) technique. The copper compound causes a decrease of ammonium perchlorate’s decomposition temperature to 372.5 °C, consequently increasing the heat release by 576 J·g−1, when used in a 5 wt% as burning rate (BR) catalyst. It must be remarked that, the [trans-Cu(μ-OH)(μ-dmpz)]6 complex presents a superior performance as BR catalyst when compared to nano-metallic oxides. This Cu(II) compound modifies the decomposition mechanism of ammonium perchlorate, providing the necessary O2 to accelerate the overall burning process paving the way to the study of copper pyrazolate complexes as BR catalysts.

Exploring the physical properties of PVA/PEG polymeric material upon doping with nano gadolinium oxide

Nano gadolinium oxide doped polyvinyl alcohol/polyethylene glycol blend (PVA/PEG) was prepared by sol–gel and casting methods. Rietveld refinement method was used for structural and microstructural investigation. The X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform infrared (FTIR) techniques were applied to study the formation of nano Gd2O3 doped PVA/PEG-blend. Differential scanning calorimetry technique (DSC) was utilized to investigate the glass transition, the melting and degradation temperatures of undoped and doped PVA/PEG blends. The melting temperature was increased slightly while the degradation temperature was reduced upon doping with nano Gd2O3. The behavior of the absorbance and other different optical parameters were studied in detail using UV-spectrophotometer. A variation in the optical bandgap of the PVA/PEG blend was observed while the values of refractive index and extinction coefficient were enhanced as the amount of Gd2O3 increased in the blend. The influence of nano Gd2O3 doping on the different dispersion parameters was examined using Wemple and DiDomenico approximation model. The nature of electronic transitions of different samples was examined by comparing the optical band gap obtained from Tauc’s relation and dielectric loss parameter.

Preparation, characterization and evaluation of fenofibrate: benzoic acid cocrystals with enhanced pharmaceutical properties

BackgroundCocrystallization process involved the understanding of interaction at molecular level between two molecules in context to their crystal packing and designing of new solids having improved physicochemical as well as pharmaceutical properties. In the present research, an attempt to increase the aqueous solubility and dissolution rate of a poorly aqueous soluble drug fenofibrate (FB) by formulation and evaluation of its cocrystals with benzoic acid (BZ) as a coformer was carried out.ResultsThe drug and coformer were cocrystallized by using the solvent drop grinding method. For prediction of cocrystals formation, CSD (Cambridge Structure Database) software was utilized. Fourier transformation infrared spectroscopy (FTIR), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) techniques were used for analysis of cocrystals. Albino rats were procured from institution as per IAEC guidelines for in vivo anti-hyperlipidaemic studies. The in vitro dissolution profile of cocrystals, pure drug, their physical mixture and marketed formulation was found to be 89%, 39%, 47% and 61%, respectively.ConclusionsAn enhanced anti-hyperlipidaemic activity of cocrystals was found compared to pure drug. The FB: BZ cocrystals also compared to the pure drug showed better dissolution profile and improved in vivo anti-hyperlipidaemic activity in rats. The study proved that cocrystals can promise to improve in vitro dissolution rate of poorly aqueous soluble drugs, which in turn can lead to better in vivo activities.

Biocompatibility studies of polyurethane electrospun membranes based on arginine as chain extender

Electrospun polymers are an example of multi-functional biomaterials that improve the material-cellular interaction and aimed at enhancing wound healing. The main objective of this work is to fabricate electrospun polyurethane membranes using arginine as chain extender (PUUR) in order to test the fibroblasts affinity and adhesion on the material and the polymer toxicity. Polyurethane membranes were prepared in two steps: (i) the polyurethane synthesis, and ii) the electrospinning process. The membranes were characterized by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy, gel permeation chromatography, and differential scanning calorimetry techniques. The evaluation of PUUR as a scaffolding biomaterial for growing and developing of cells on the material was realized by LIVE/DEAD staining. The results show that the fluorescent surface area of human fibroblasts (hFB), was greater in control dense membranes made from Tecoflex than in electrospun and dense PUUR. From SEM analysis, the electrospun membranes show relatively uniform attachment of cells with a well-spread shape, while Tecoflex dense membranes show a non-proliferating round shape, which is attributed to the fiber’s structure in electrospun membranes. The cell morphology and the cell attachment assay results reveal the well spreading of hFB cells on the surface of electrospun PUUR membranes which indicates a good response related to cell adhesion.

DSC study on combustion behavior of tahe heavy oil and its low temperature oxidation products

In this study, the combustion behaviors of heavy oil and low temperature oxidation products were analyzed by differential scanning calorimetry (DSC) technique. The results elucidated that the coke formed after static oxidation showed the highest heat release (24.03 kJ/g), which was a positive signal for the in-situ combustion (ISC) process of Tahe heavy oil. The most abundant asphaltenes in heavy oil and residue contributed more fuel for high temperature oxidation (HTO), resulting the two samples to exhibit intense HTO reactions. In summary, activation energies of the samples in the low temperature oxidation (LTO) were higher than that in HTO region.

New Application of Electrically Conductive Adhesive as a Transistor-based Electrical Circuit under AC and DC Currents

Electrically conductive composite adhesives containing 70, 75 and 85 wt% of filler particles (Cu@Ag) and polymer matrix were prepared. Thermal stability and morphology of the prepared adhesives were examined using TG (Thermo-Gravimetry), DSC (Differential Scanning Calorimetry), and Scanning Electron Microscope(SEM) techniques. In the next step, a transistor-based electrical circuit using self-biased common-emitter combination was made from the prepared conductive adhesive as well as a copper board. All of the prepared boards were subjected to DC (8-30 V) and AC (1 kHz) currents to evaluate their performance. For these circuits, parameters such as transistor operating points and the voltage gain of the amplifier, were measured. TG and DSC analyses showed that increasing the filler amount from 70 to 85 wt%, reduces the weight loss of the adhesive from 15.48 to 11.35 wt%. Also, effect of increasing the silver amount in Cu@Ag particles on the thermal stability of adhesives at temperatures below 350 °C showed that by increasing of the amount of silver from 20 to 40 wt%, has a negligible effect on weight change (about 2 wt% at 250 °C). Both samples showed almost the same overall weight loss at 350 °C. Evaluation of circuit performance showed that the changes in circuit width (1, 1.5, and 2 mm) has no significant effect on the V–I characteristics and voltage gain. The value of these two parameters for all three circuits and also the copper board circuit were the same which indicates the high conductivity of the prepared conductive adhesive.

Thermal degradation kinetics of ethyl vanillin crosslinked chitosan/poly(vinyl alcohol) blend films for food packaging applications

The precise knowledge of thermal degradation of polymers appears to be of great importance in order to identify their applications. In the present work ethyl vanillin (EV) cross linked chitosan (CS)/poly(vinyl alcohol) (PVA) (CPEV) blend films of different mass percent were prepared by solvent casting method, and were characterized by using thermogravimetric/derivative thermogravimetric (TG/DrTG), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques. Non-isothermal (dynamic) thermogravimetry was used with three different heating rates (β) namely 5.0, 7.5 and 10.0∘Cmin−1 Kinetic parameters such as activation energy (Ea) and pre exponential factor (A) were calculated using Flynn-Wall-Ozawa (FWO) equation, Kissinger-Akahira-Sunose (KAS) equation and Kissinger relation at three different stages of thermal degradation. The improved thermal staCDC100739ility of EV crosslinked blend films could be due to the formation of Schiff base and inter molecular hydrogen bonding. Calculated percentage of crystallinity (X%) results from DSC and XRD data found to be in good agreement with each other. Crystallinity decreased with increase of CS percent in CPEV blend films.

Modulation of Crystallinity through Radiofrequency Electromagnetic Fields in PLLA/Magnetic Nanoparticles Composites: A Proof of Concept.

To modulate the properties of degradable implants from outside of the human body represents a major challenge in the field of biomaterials. Polylactic acid is one of the most used polymers in biomedical applications, but it tends to lose its mechanical properties too quickly during degradation. In the present study, a way to reinforce poly-L lactic acid (PLLA) with magnetic nanoparticles (MNPs) that have the capacity to heat under radiofrequency electromagnetic fields (EMF) is proposed. As mechanical and degradation properties are related to the crystallinity of PLLA, the aim of the work was to explore the possibility of modifying the structure of the polymer through the heating of the reinforcing MNPs by EMF within the biological limit range f·H < 5·× 109 Am−1·s−1. Composites were prepared by dispersing MNPs under sonication in a solution of PLLA. The heat released by the MNPs was monitored by an infrared camera and changes in the polymer were analyzed with differential scanning calorimetry and nanoindentation techniques. The crystallinity, hardness, and elastic modulus of nanocomposites increase with EMF treatment.

Temperature and Composition Dependence of the Thermodynamic Properties of an Aqueous Solution of 1-Ethyl-3-methylimidazolium Formate and 1-Ethyl-3-methylimidazolium Acetate

New experimental data on the thermodynamic properties of imidazolium-based ionic liquids (ILs) and {IL + water} solutions are presented. The isothermal (vapor + liquid) phase equilibrium (VLE) and the density of binary mixtures composed of 1-ethyl-3-methylimidazolium formate, [EMIM][HCOO], or 1-ethyl-3-methylimidazolium acetate, [EMIM][CH3COO], and water are demonstrated. The experimental data were measured at temperatures from 298.15 to 348.15 K over a wide IL mole fraction under ambient pressure. Both ILs were delivered by IoLiTec, and the water content was determined by the Karl–Fischer titration technique. The thermophysical properties of the pure ILs, that is, glass-transition temperature, heat capacity at glass-transition change, and the temperature and enthalpy of melting, were determined by differential scanning calorimetry technique. The VLE has been measured by an ebulliometric method at temperatures from 338.15 to 368.15 K and pressures up to 85 kPa. The experimental VLE data were tested for thermodynamic consistency using the Van Ness test. The nonrandom two-liquid model equation was used to correlate the experimental VLE data. The density of the tested aqueous solution has been measured as a function of IL’s mole fraction over a wide temperature range. The empirical equations were applied for density data correlation. From the experimental density data for the {[EMIM][CH3COO] (1) + water (2)} system, the excess molar volumes were determined and correlated using the Redlich–Kister equation.

Reaction characteristic of PTFE/Al/Cu/Pb composites and application in shaped charge liner

In this paper, the reaction characteristic and its application in shaped charge warhead of a novel reactive material, which introduced copper (Cu) and plumbum (Pb) into traditional polytetrafluoroethylene/aluminum (PTFE/Al), are studied. The thermal analysis and chemical reaction behavior of the PTFE/Al/Cu/Pb mixture are investigated by Differential Scanning Calorimetry (DSC),Thermo-gravimetry (TG), and X-ray Diffraction (XRD) techniques. Then, the shaped charge liners with PTFE/Al/Cu/Pb reactive materials are fabricated, and the X-ray experiments show that they could form reactive jets with excellent performance under the detonation effects of the shaped charge. Based on that, the penetration experiments of shaped charge with PTFE/Al/Cu/Pb reactive liner against steel plates are carried out, and the results demonstrate that the PTFE/Al/Cu/Pb reactive jets could produce a deeper penetration depth compared to the traditional PTFE/Al reactive jets. Meanwhile, the PTFE/Al/Cu/Pb reactive jets also show significant inner-blast effects, leading to dramatically cracking or fragmentation behavior of the penetrated steel plates. This new PTFE/Al/Cu/Pb reactive liner shaped charge presents enhanced penetration behavior for steel targets that incorporates the penetration capability of a high-density and ductility jet, and the chemical energy release of PTFE-matrix reactive materials.

Analysis and Investigation of Thermal Runaway Propagation for a Mechanically Constrained Lithium-Ion Pouch Cell Module

In this paper, tests and analysis of thermal runaway propagation for commercial modules consisting of four 41 Ah Li-ion pouch cells are presented. Module samples were tested at 100% state-of-charge and mechanically constrained between two steel plates to provide thermal and mechanical contact between the parts. Voltage and temperature of each cell were monitored during the whole experiment. The triggering of the exothermal reactions was obtained by overheating one cell of the stack with a flat steel heater. In preliminary studies, the melting temperature of the separator was measured (from an extracted sample) with differential scanning calorimetry and thermogravimetric analysis techniques, revealing a tri-layers separator with two melting points (≈135 °C and ≈170 °C). The tests on module level revealed 8 distinct phases observed and analyzed in the respective temperature ranges, including smoking, venting, sparkling, and massive, short circuit condition. The triggering temperature of the cells resulted to be close to the melting temperature of the separator obtained in preliminary tests, confirming that the violent exothermal reactions of thermal runaway are caused by the internal separator failure. Postmortem inspections of the modules revealed the internal electrical failure path in one cell and the propagation of the internal short circuit in its active material volume, suggesting that the expansion of the electrolyte plays a role in the short circuit propagation at the single cell level. The complete thermal runaway propagation process was repeated on 5 modules and ended on average 60 s after the first thermal runaway triggered cell reached a top temperature of 1100 °C.

Thermodynamic characterization of {1-ethyl-1-methyl-pyrrolidinium dimethylphosphate, [C1C2PYR][DMP], or 1-hydroxyethyl-1-methylpyrrolidinium dimethylphosphate, [C1C2OHPYR][DMP] (1) + ethanol (2)} binary systems

In this work, {1-ethyl-1-methylpyrrolidinium dimethylphosphate, [C1C2PYR][DMP], or 1-hydroxyethyl-1-methylpyrrolidinium dimethylphosphate, [C1C2OHPYR][DMP] (1) + ethanol (2)} binary systems were studied as an alternative working pair for the absorption heat pump cycle. It is well known that the knowledge of the thermodynamic properties of the working fluid used plays a key role in the coefficients of performance values, and thus in the efficiency of the apparatus. Therefore, in this work thermodynamic and physicochemical characteristics of ethanol solutions of two dimethylphosphate-based ionic liquids are presented. The isothermal VLE was measured by an ebulliometric method within a temperature range from T = (328.15 to 348.15) K with an increment of 10 K and pressures up to 90 kPa. Experimental VLE data have been successfully correlated using the NRTL equation using temperature-dependence parameters. Additionally, experimental VLE data were tested for thermodynamic consistency using the Van Ness test. The liquid density and dynamic viscosity were determined as a function of IL's mole fraction over a wide composition range at temperature from T = (293.15 to 338.15) K with an increment of 5 K at ambient pressure. For the correlation of physicochemical properties, empirical equations were applied. From experimental density data, the excess molar volumes were determined and correlated using the Redlich – Kister type equation. Additionally, thermophysical properties of pure ILs including glass transition temperature, heat capacity at glass transition, temperature and enthalpy of (solid + solid) phase transition as well as temperature and enthalpy of melting were determined using differential scanning calorimetry (DSC) technique. Data presented in this work, compared to the available literature data for ethanolic solutions of other dimethylphosphate-based ILs, allows discussing the impact of the IL's cation structure on the presented physicochemical and thermodynamic properties. In addition, the data presented in this work were compared to data for a water solution of lithium bromide, commercially used in absorption refrigeration technology.

Effect of Stretching on Crystalline Structure, Ferroelectric and Piezoelectric Properties of Solution-Cast Nylon-11 Films.

Compared to polyvinylidene fluoride (PVDF) and its copolymers, castor-oil-derived nylon-11 has been less explored over the past decades, despite its excellent piezoelectric properties at elevated temperatures. To utilize nylon-11 for future sensor or vibrational energy harvesting devices, it is important to control the formation of the electroactive δ′ crystal phase. In this work, nylon-11 films were first fabricated by solution-casting and were then uniaxially stretched at different stretching ratios (SR) and temperatures (Ts) to obtain a series of stretched films. The combination of two-dimensional wide-angle X-ray diffraction (2D-WAXD) and differential scanning calorimetry (DSC) techniques showed that the fraction of the δ′ crystal phase increased with the stretching ratio and acquired a maximum at a Ts of 80 °C. Further, it was found that the ferroelectric and piezoelectric properties of the fabricated nylon-11 films could be correlated well with their crystalline structure. Consequently, the stretched nylon-11 film stretched at an SR of 300% and a Ts of 80 °C showed maximum remanent polarization and a remarkable piezoelectric coefficient of 7.2 pC/N. A simple piezoelectric device with such a nylon-11 film was made into a simple piezoelectric device, which could generate an output voltage of 1.5 V and a current of 11 nA, respectively.

Critical evaluation and thermodynamic modeling of the Ag-X (X=Mn, Y, Sr) binary systems

A complete literature review, critical evaluation and thermodynamic assessment of the Ag-X (X = Mn, Y, Sr) binary systems have been conducted. The Modified Quasi-chemical Model in the Pair Approximation (MQMPA) was applied to describe the Gibbs energy of the liquid phase. The Gibbs energy of all intermetallic compounds and terminal solid solutions was described by the Compound Energy Formalism (CEF). The critical literature assessment and thermodynamic modeling of the Ag–Mn binary system were carried out for the first time. The Differential Scanning Calorimetry (DSC) measurement was carried out to resolve the discrepancy of liquidus in Ag-rich region of the Ag–Sr binary system. Thermodynamic re-optimization of the Ag–Sr binary system was performed based on reported literature data and our new measured results using DSC technique. Thermodynamic re-optimization of the Ag–Y binary system was also carried out with considering the ordered bcc_B2 crystal structure of the AgY compound. All reliable experimental data are well reproduced within the experimental limits. A self-consistent thermodynamic database of the Ag-X (X = Mn, Y, Sr) binary systems was constructed for the development of new biomaterials.