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Silica phosphate glasses strengthened with a calcium oxide modifier and doped with different concentrations (0%, 0.5%, 1%, 1.5 mol%) of praseodymium (Pr3+) were synthesized by a sol–gel method. The absence of sharp peaks in the X-ray diffraction spectra confirms the noncrystallinity of the glasses. Higher doping indicates increasing optical bandgaps due to Burstein–Moss shift, which also reflects on structural disorders at the absorption tails, as validated by Urbach's rule. The density increases with a subsequent decrease in oxygen-packing density, proving the mechanical and chemical stability of the glasses. The composite glasses are multifunctional with marked absorption at 280 nm predicting their purpose as UV shielding films. Luminescence corresponding to the intra 4f transition, 1 D 2 → 1 G 4 in the infrared region, with high transmission and low reflection losses suggests the use of the synthesized glass material for S-band telecommunications, while the radiative process involving 3 P 0 → 3 F 2 yields a predominant red laser source. Commission International de l'Eclairage color coordinates observe warmer red emission corresponding to a correlated color temperature of 3200 K. The composite silica phosphate glass systems evidence the effective role of Pr3+ for photonic applications. [ABSTRACT FROM AUTHOR]

To enhance the working quality of WLEDs, considerable efforts have been made to upgrade the thermal quenching resistance of existing phosphors or design new anti-thermal quenching (ATQ) phosphors. Developing a new phosphate matrix material with special structural features has great importance for the fabrication of ATQ phosphors. By phase relationship and composition analysis, we have prepared a novel compound Ca3.6In3.6(PO4)6 (CIP). Coupling ab initio and Rietveld refinement techniques, the novel structure of CIP with partly vacant cationic positions was solved. Taking this unique compound as the host and using the inequivalent substitution of Dy3+ for Ca2+, a series of C1−xIP:Dy3+ rice-white emitting phosphors were successfully developed. When the temperature was raised to 423 K, the emission intensity of C1−xIP:xDy3+ (x = 0.01, 0.03, and 0.05) increased to 103.8%, 108.2%, and 104.5% of the original intensity at 298 K, respectively. Except for the strong bonding network and inherent cationic vacancy in the lattice, the ATQ property of the C1−xIP:Dy3+ phosphors is mainly attributed to the generation of interstitial oxygen from the substitution of unequal ions, which releases electrons with the thermal stimulus, causing anomalous emission. Finally, we have explored the quantum efficiency of C1−xIP:0.03Dy3+ phosphor and the working performance of PC-WLED prepared with C1−xIP:0.03Dy3+ phosphor and 365 nm chip. The research work sheds light on the relationship between lattice defects and thermal stability, and meanwhile offers a new strategy for the development of ATQ phosphors. [ABSTRACT FROM AUTHOR]

To enhance the working quality of WLEDs, considerable efforts have been made to upgrade the thermal quenching resistance of existing phosphors or design new anti-thermal quenching (ATQ) phosphors. Developing a new phosphate matrix material with special structural features has great importance for the fabrication of ATQ phosphors. By phase relationship and composition analysis, we have prepared a novel compound Ca3.6In3.6(PO4)6 (CIP). Coupling ab initio and Rietveld refinement techniques, the novel structure of CIP with partly vacant cationic positions was solved. Taking this unique compound as the host and using the inequivalent substitution of Dy3+ for Ca2+, a series of C1−xIP:Dy3+ rice-white emitting phosphors were successfully developed. When the temperature was raised to 423 K, the emission intensity of C1−xIP:xDy3+ (x = 0.01, 0.03, and 0.05) increased to 103.8%, 108.2%, and 104.5% of the original intensity at 298 K, respectively. Except for the strong bonding network and inherent cationic vacancy in the lattice, the ATQ property of the C1−xIP:Dy3+ phosphors is mainly attributed to the generation of interstitial oxygen from the substitution of unequal ions, which releases electrons with the thermal stimulus, causing anomalous emission. Finally, we have explored the quantum efficiency of C1−xIP:0.03Dy3+ phosphor and the working performance of PC-WLED prepared with C1−xIP:0.03Dy3+ phosphor and 365 nm chip. The research work sheds light on the relationship between lattice defects and thermal stability, and meanwhile offers a new strategy for the development of ATQ phosphors. [ABSTRACT FROM AUTHOR]

The copper containing glass, particularly with rich Cu+ ions, is a promising material for antibacterial and luminescent. The valence control of Cu+/Cu2+ in melt-quenching glass has been widely investigated, but sol-gel method was rarely extended. Herein, the Cu+ rich silicate glass was successfully prepared by introducing the P 2 O 5 as modifying agent in the sol-gel method fabricated phosphosilicate glasses, briefed as 10CaO-(90-x)SiO 2 -xP 2 O 5 (x = 0, 2.5, 5, 7.5, 10 mol%)- 5CuO. It is found that the high content of P 2 O 5 will generates more Cu+ in the gel forming stage and result in a Cu+ rich glass. While, the content of Cu+ drops with excessive P 2 O 5 additives in the prepared glass. The highest Cu+ content was obtained in glass with 7.5 mol% P 2 O 5. Because phosphate glass network is looser than silica-oxygen glass network, which lead to copper ion in the phosphate cluster as a charge compensator is easier to be oxidized compared with in the Si–O network. Therefore, our study paved a new way for designing Cu+ rich glass by sol-gel method. [ABSTRACT FROM AUTHOR]

In this experiment, 20P 2 O 5 –50SnF 2 -(30-x-y)SnO-xWO 3 -yB 2 O 3 (x = 0,y = 0,5,10,15; x = 5,10,15,y = 0; x = 10,5, y = 5,10mol%) phosphate glasses were prepared. In this paper, the effect of the addition of WO 3 and B 2 O 3 on the properties of phosphate glasses was investigated. The results show that the network structure of all glass samples is basically composed of Q 1 and Q 0 short chain groups. The addition of WO 3 disrupts the network structure of the glass and leads to a decrease in the glass thermal, mechanical, corrosion properties. B 2 O 3 participates in the formation of the glass as a [BO 4 ] structural unit, which strengthens the network structure and thus improves the glass properties. However, with the increase of B 2 O 3 , some of the B 2 O 3 existed as [BO 3 ], which reduced the cross-linkage of the glass structure and the glass properties appeared abnormal. In the glass with the coexistence of WO 3 and B 2 O 3 , the glass properties were better, especially the chemical stability of the glass was significantly improved. The smallest weight loss rate in the aqueous solution is only 9.52 × 10−7 g·cm−2·min−1. [ABSTRACT FROM AUTHOR]

The possibility of creating a stable joint of materials with different values of the linear thermal expansion coefficient (LTEC) was demonstrated by means of femtosecond laser beam welding: phosphate glass and zinc-magnesium-aluminum-silicate sitall (their values of the LTEC lie in the range 20 – 300°C: 120 × 10 –7 K–1 and 62 × 10 –7 K–1 respectively. Optical microscopy and Raman spectroscopy were used to investigate the structural features of welds obtained by different laser welding regimes and to optimize the laser welding regimes. [ABSTRACT FROM AUTHOR]

Ca(PO3)2–AlF3–CaF2–BaF2–BaO glasses were prepared by the melt quenching method, and the effects of the O/P ratio on the optical properties and glass structure were investigated. The bandgap energy showed no significant change at O/P = 3.0–3.4 but drastically decreased with the increase in the O/P from 3.6 to 4.0. In addition, the refractive index dispersion was analyzed based on the Lorentz model, and it was found that the decrease in the resonance frequency in the ultraviolet region with the increase in the O/P ratio resulted in an increase in the refractive index and dispersion. Analysis of the infrared absorption and Raman scattering spectra revealed that the phosphate chains were broken, and isolated Q0 units were generated with the increase in the O/P ratio from 3.6 to 4.0. Based on the structural change of the glass, the origin of the nonlinear dependence of the optical properties on the O/P ratio was discussed. [ABSTRACT FROM AUTHOR]

We report on the fabrication, properties, and structure of cerium pyrophosphate glasses and partially substituted cerium silicophosphates. In those glasses, cerium occurs predominantly as Ce(III). A combination of dynamic nuclear magnetic resonance and electrical impedance spectroscopy is used to overcome the problem of assessing cerium speciation. While optical spectroscopy is unable to quantify the ratio of Ce(III)/Ce(IV) due to spectral overlap, proxy observations of the effect of silica‐for‐cerium substitution on optical extinction and the shape and width of the UV band gap corroborate vibrational spectroscopic data of the structural roles of cerium and silica. While silica bonding to phosphate units appears to stabilize Ce(IV), it also impedes the polaron transport, leading to higher polaron activation energy and lower electronic conductivity. On the other hand, Ce(III) is stabilized by coordinating to P = O. [ABSTRACT FROM AUTHOR]

Asteroid 4 Vesta is the largest known differentiated body in the asteroid belt, and is thought to be the likely parent body of howardite, eucrite, and diogenite (HED) meteorites. Howardites likely represent the vestan surface, eucrites likely crystallized as lavas in the upper crust, and diogenites likely originated from a plutonic layer deep in the crust. HEDs are potentially linked to another group of meteorites: the stony-iron mesosiderite group, due to mineralogical, geochemical, and isotopic similarities. Collision and disruption processes in the asteroid belt are key to understanding the evolution of asteroids, with impact events generating significant volumes of melt, which, if dated, can provide information on the timing and nature of such events. We performed in situ lead-lead (Pb-Pb) dating using Secondary Ionization Mass Spectrometry (SIMS) on melt clasts (mainly comprised of pyroxene, plagioclase, ± iron-nickel metal and/or glass) in two eucrites (Serra Pelada and Northwest Africa (NWA) 2696) and phosphates targeted within three mesosiderites (Vaca Muerta, Hainholz, and Estherville), respectively. The eucrite melt clasts yielded ages of 4520 ± 11 Ma and 4528.6 ± 6.3 Ma, in Serra Pelada and NWA 2696, respectively, and are likely indicative of a major heating event, such as an impact, metamorphism due to burial, or prolonged magmatism on the parent body. Our results from targeted mesosiderite phosphate analysis yielded a younger age range of ∼3968 – 4112 Ma, similar to ages reported previously for phosphate analysis in eucrites, as well as the broad range observed previously for many HEDs, and towards the upper end of the age range observed in lunar materials. These data may suggest a period of increased impact flux or possibly several higher-magnitude impacts on the mesosiderite parent body within that timeframe. Our results add further support to the likelihood of the existence of (at least) two different parent bodies for the HEDs (Vesta) and mesosiderites (Mesosiderite Parent Body – MPB). [ABSTRACT FROM AUTHOR]

Calcium phosphate glasses (CPG) with varying concentrations of uranium were synthesized by melt quench method. Maximum solid solubility of uranium in CPG was determined by using X-ray diffraction technique. Heat capacity (Cp) of the pristine CPG and uranium-loaded CPG was measured by drop calorimetry and differential scanning calorimetry. Heat capacity measured by drop calorimetry of pristine glass (CPG) was found to be 0.74 Jg−1 K−1at 298 K; on loading 0.8 mol% of uranium oxide, Cp value decreased to 0.58 Jg−1 K−1 and further higher loading of 2 mol% uranium oxide shows further reduction of Cp to 0.55 Jg−1 K−1. This decrease in Cp may be due to the weakening of glass network structure as uranium loading increases into glass matrix. Ratio of the number of bridging to non-bridging oxygen is decreasing gradually on increasing the amount of uranium in glass. The same has been observed for the DSC measurement as well; where the pristine glass (CPG) has higher heat capacity values compared to CPG-0.8 and CPG-2. In case of DSC, CPG-0.8 shows slightly lower values of heat capacity compared to CPG-2, this may be due to the structural changes by which the bonding between the atoms may slightly increase while going to higher amount of waste constituents. Glass transition temperature (Tg) of the glass matrices has been measured and it shows gradual increase on loading uranium in glass matrix from 0.8 to 6 mol%. [ABSTRACT FROM AUTHOR]

Ion-substituted calcium phosphate (CP) coatings have been extensively studied as promising materials for biomedical implants due to their ability to enhance biocompatibility, osteoconductivity, and bone formation. This systematic review aims to provide a comprehensive analysis of the current state of the art in ion-doped CP-based coatings for orthopaedic and dental implant applications. Specifically, this review evaluates the effects of ion addition on the physicochemical, mechanical, and biological properties of CP coatings. The review also identifies the contribution and additional effects (in a separate or a synergistic way) of different components used together with ion-doped CP for advanced composite coatings. In the final part, the effects of antibacterial coatings on specific bacteria strains are reported. The present review could be of interest to researchers, clinicians, and industry professionals involved in the development and application of CP coatings for orthopaedic and dental implants. [ABSTRACT FROM AUTHOR]

A helicene‐containing arene and its linear analogue have been successfully synthesized and characterized, where the single‐crystal X‐ray diffraction analysis indicates that the former can arrange in an offset packing style with a π‐π overlap. The introduction of pentagon‐rings into the parent skeletons in the resulting compounds can boost the stability, and such helicene‐containing molecule possesses higher solubility in organic solvent than the linear analogue. The structural difference has significantly influenced the optical limiting performance. The former in solution and in doped gel glass presents higher optical limiting response towards 532 nm laser than the latter. This study can enrich the functionalization of helicene, which can possess a positive effect in terms of nonlinear optical property. [ABSTRACT FROM AUTHOR]

[Display omitted] • Direct regeneration of anode material into high-performance P-doped graphite. • The mechanism of phosphorus change during calcination was revealed. • The P-doped graphite promotes the formation of SEI and widens layer spacing. • The regenerated battery has outstanding reversibility and cycle performance. Recycling graphite from spent lithium-ion batteries has been largely ignored. In the present work, we propose a novel purification process, which modifies the structure of graphite through phosphoric acid leaching-calcination to obtain high-performance phosphorus (P)-doped graphite (LG-temperature) and lithium phosphate products. The content analysis of X-ray photoelectron spectroscopy (XPS), X-ray fluorescence (XRF) and scanning electron microscope focused ion beam (SEM-FIB) indicates that the LG structure is deformed by the doped P atom. The results of In-situ fourier transform infrared spectroscopy (In-situ-FTIR), density functional theory (DFT) calculation and XPS analysis show that the surface of the leached spent graphite contains rich oxygen groups, which react with phosphoric acid at high temperatures and form stable C-O-P and C-P bonds, making it easier to form stable solid electrolyte interface (SEI) layer. The increase of layer spacing is confirmed by X-ray diffraction (XRD), Raman and transmission electron microscope (TEM), which is conducive to the formation of efficient Li+ transport channels. What is more, Li/LG-800 cells possess high reversible specific capacities of 359, 345, 330 and 289 mA h g−1 at 0.2C, 0.5C, 1C and 2C, respectively. After 100 cycles at 0.5C, the specific capacity is as high as 366 mAh g−1, demonstrating the outstanding reversibility and cycle performance. This study proves and highlights a promising recovery route for exhausted lithium-ion batteries anodes, making complete recycling possible. [ABSTRACT FROM AUTHOR]

Reflectance spectroscopy is a powerful tool to remotely identify the mineral and chemical compositions of the lunar regolith. The lunar soils contain silicate minerals with prominent absorption features and glasses with much less distinctive spectral features. The accuracy of mineral abundance retrieval may be affected by the presence of glasses. In this work, we construct a spectral library of mixtures of major lunar-type minerals and synthetic glasses with varying relative abundances and test their performance on mineral abundance retrievals. By matching the library spectra with the spectra of mineral mixtures with known abundances, we found that the accuracy of mineral abundance retrieval can be improved by including glass as an endmember. Although our method cannot identify the abundance of glasses quantitatively, the presence or absence of glasses in the mixtures can be decisively determined. [ABSTRACT FROM AUTHOR]

Solar cells in superstrate arrangement need a protective cover glass as one of its main components. The effectiveness of these cells is determined by the cover glass's low weight, radiation resistance, optical clarity, and structural integrity. Damage to the cell covers brought on by exposure to UV irradiation and energetic radiation is thought to be the root cause of the ongoing issue of a reduction in the amount of electricity that can be generated by solar panels installed on spacecraft. Lead-free glasses made of xBi2O3–(40 − x)CaO-60P2O5 (x = 5, 10, 15, 20, 25, and 30 mol%) were created using the usual approach of melting at a high temperature. The amorphous nature of the glass samples was confirmed using X-ray diffraction. At energies of 81, 238, 356, 662, 911, 1173, 1332, and 2614 keV, the impact of various chemical compositions on gamma shielding in a phospho-bismuth glass structure was measured. The evaluation of gamma shielding revealed that the results of the mass attenuation coefficient of glasses increase as the Bi2O3 content increases but decrease as the photon energy increases. As a result of the study conducted on the radiation-deflecting properties of ternary glass, a lead-free low-melting phosphate glass that exhibited outstanding overall performance was developed, and the optimal composition of a glass sample was identified. The 60P2O5–30Bi2O3–10CaO glass combination is a viable option for use in radiation shielding that does not include lead. [ABSTRACT FROM AUTHOR]

Quim Tarrés et al. studied the interface strength and fiber content influence on corn-stover-fiber-reinforced bio-polyethylene composites' stiffness [[9]]. This Special Issue aimed to provide a forum for the discussion of recent advances in the analysis and characterization of polymer-based composites. Angxuan Wu et al. used this same material (fly ash) in the paper "Preparation and Finite Element Analysis of Fly Ash/HDPE Composites for Large Diameter Bellows" [[6]] to produce high-density polyethylene composites. 33805018 9 Tarrés Q., Hernández-Díaz D., Ardanuy M. Interface Strength and Fiber Content Influence on Corn Stover Fibers Reinforced Bio-Polyethylene Composites Stiffness. [Extracted from the article]

Cobalt-containing materials are of interest for a wide range of applications, from biomaterials to solid-state lasers in optics. For instance, Co2+ is known to trigger the formation of new blood vessels, i.e. angiogenesis. Here, the use of phosphate glasses as a vehicle for local release of Co2+ ions is an attractive strategy to overcome the vascularisation limitation in tissue engineering. This study aimed to establish structure–property correlations as a function of the coordination environment of cobalt in 45P2O5–(30 − x)CaO–25Na2O–xCoO (x: 0.01 to 10 mol%) glasses. Constant polymerization and O/P ratio, resulting ultimately in constant basicity, were shown by ICP-OES and Raman spectroscopy. The latter, combined with EPR analysis, indicated that Co2+ was the predominant oxidation state and the presence of Co3+ can be excluded. UV–vis–NIR absorption spectra showed that the ratio between Co2+ in four- and six-fold coordination remained constant throughout the glass series. Their thermal properties measured by DSC and heating microscopy did not change much in the substitution range studied here. The steady trend in Tg values suggests a compensation between two opposite effects caused by the presence of four and six-fold coordinated Co2+, both being present at a constant ratio throughout the glasses. Accordingly, the higher field strength of Co2+ compared to that of Ca2+ is expected to strengthen the glass network. In contrast, four-fold coordinated cobalt is expected to weaken the network by connecting fewer fragments of the phosphate glass network than six-fold coordinated cobalt. These results indicate that the structural properties of the glasses with constant basicity are influenced by the coordination number of Co2+. [ABSTRACT FROM AUTHOR]

Bioactive glasses (BGs) are characterized by high biocompatibility and bioactivity and are particularly promising for bone tissue regeneration. Once implanted, the BGs interact with the environment and adsorb chemical moieties and biomolecules. Proteins in body fluids are critical for the success of implants, because the adsorption of specific proteins can either promote or inhibit the adhesion of surrounding tissue or other factors such as bacteria. Controlling protein adsorption by tailoring the surface properties of implanted biomaterials is fundamental. This can determine the fate of the implant. In the current study, four BG compositions (two silicates, one borosilicate, and one phosphate glass) and three model proteins (fibronectin, chimeric avidin, and streptavidin) were considered. Each BG was surface pretreated, and the adsorption of fluorescently labeled fibronectin, chimeric avidin, or streptavidin was monitored. Untreated surfaces were used as controls. The amount and spatial distribution of each protein were estimated by confocal microscopy in fluorescence modality, followed by protein clustering analysis. Although streptavidin was not adsorbed efficiently on any of the considered substrates, BGs were successfully coated with fibronectin and chimeric avidin. Both proteins showed different affinities and surface distributions as functions of the implemented pretreatment on each substrate. [ABSTRACT FROM AUTHOR]

Biocomposite is extensively implemented in orthopaedics and dentistry since multiple materials blends can be utilised by capitalising on their radical compatibility. Bioactive glasses (BG) and β-tricalcium phosphate (β-TCP) have excellent bioactive, osteoconductive, and osteogenic features due to the resemblance of their inorganic constituents with bone or dental tissue. In this study, sol–gel BG was incorporated with β-TCP for potential application in dental tissue engineering. A 40/60 composition ratio of BG/β-TCP powder was homogeneously mixed in a zirconia planetary ball mixer and sieved to obtain particle size of less than 50 μm. The BG/β-TCP powder composite was characterised using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electronic microscopy (SEM), laser diffraction particle size analyser, and in vitro biological characteristics were observed by soaking the BG/β-TCP composite in simulated body fluid (SBF) and exposing the Saos-2 cells towards conditioned medium. The XRD analysis identified the presence of whitlockite (ICCD 00–009-0169) and combeite (ICDD 96–900-7722) crystalline phase in the composite structure. The pH tends to be in the range of 7.7 to 8.0 throughout the study period, and SEM exhibited the hydroxyapatite (HA) formation on the surface after 1 day when immersed in SBF. Based on in vitro investigation, the BG/β-TCP composite presented enhanced cell adhesion and proliferation. In this preliminary study, in vitro HA formation ability, and cell proliferation properties may have considered the BG/β-TCP biocomposite as a potential for bone and dental tissue engineering. [ABSTRACT FROM AUTHOR]

Nuclear energy generation technology is critically linked with the safe disposal of radioactive waste. In this context, iron phosphate glass (IPG) is gaining predominance as nuclear waste vitrification matrix that necessitates a thorough study on the effect of the loading of various nuclear fission waste materials in it. In this study, the effect of the loading of Nd3+ (which acts as a surrogate for radioactive curium (Cm)) and Ru4+ (which is a fission product of 235U) in IPG has been assessed. The optimum loading of Nd3+/Ru4+ leading to the formation of homogenous melt has been ascertained via powder X‐ray diffraction and scanning electron microscopy techniques. The modification in the Fe3+/Fe2+ ratio in IPG and the consequent change in its average coordination number with Nd3+/Ru4+ loading has been deduced from the Mössbauer studies. Local structure analysis has been done using X‐ray absorption spectroscopy at Nd/Ru/Fe K‐edge (as applicable) for all the single and co‐loaded IPG samples. All the co‐loaded samples show enhanced glass stability and glass forming ability compared to unloaded IPG which has been ascertained via detailed thermal studies. The variation in IPG network structure on the addition of Nd2O3 and RuO2 has been ascertained through spectroscopic techniques like Fourier transform infrared (FTIR) and Raman. The base glass and a few representative homogenous single and co‐loaded IPG samples have been irradiated with 4.5 MeV proton beam to simulate the hosting of radioactive elements and the radiation effect on glass structure has been ascertained using FTIR and Raman spectroscopies. The suitability of IPG as nuclear waste vitrification matrix for Nd3+ and Ru4+ is established through all the above analyses. [ABSTRACT FROM AUTHOR]

The efficient 810 nm laser energy conversion of glass frit had been proven to be the key to the long‐term hermetic encapsulation of Organic Light Emitting Display (OLED). A direct laser energy conversion laser‐assisted Bi2O3‐B2O3‐ZnO‐Nd2O3 sealing glass material without extra laser absorbent such as carbon black, was designed and systematically investigated. The addition of Nd2O3, as glass modifiers with higher cationic field strength, could be conducive to enhancing the polymerization of glass network structure, manifesting that the glass‐transition temperature Tg, onset‐crystallization temperature Tc and thermal stability ΔT (ΔT = Tc‐Tg) increased, while thermal expansion coefficient CTE dropped to 9.72×10−6/°C and advantageously matched with the glass substrate (8±1×10−6/°C). More importantly, the absorption rate of BBZ‐Nd glass was more than 50 % between 800∼810 nm owing to the 4f‐4f electron transition of Nd3+ ions, and yet the reflectivity and transmittance of the wavelength at 800–810 nm were lower. As optimal compositions, the addition of 3.0 wt% Nd2O3 in Bi2O3‐B2O3‐ZnO‐Nd2O3 glass frit with higher absorption coefficients (80 %) led to instantaneous bonding encapsulation between glass substrates without interfacial cracks or pores with the 808 nm wavelength of the laser at 20 W and 2.4 mm/s. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the antibacterial [minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC)] and antibiofilm activity [log10 colony forming unit/mL (CFU/mL) and biofilm disruption] of copper-doped phosphate glass (CDPG) against Streptococcus oralis, Enterococcus faecalis, Lactobacillus casei, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Methods: the antibacterial activity was determined using microbroth dilution and time-kill assay. The antibiofilm activity was investigated using crystal violet and confocal laser scanning microscopy. Bacteria growing in absence of CDPG were used as controls. Results: the MIC was ≥125 mg of CPDG/mL; the log10 CFU/mL reduction ranged from 2.66–3.14 to 6.23–9.65 after 4 and 24 h respectively. Generally, no growth was observed after 24 h of treatment with CDPG; the MBC was 250 mg/mL for L. casei and S. oralis while 500 mg/mL for the rest of the bacteria. The highest and lowest antibiofilm activity was observed against S. oralis and E. coli respectively. Three patterns of complete biofilm disruption were seen: (i) large areas with E. fecalis and S. oralis, (ii) medium-size pockets with S. aureus and P. aeruginosa, or (iii) small areas with E. coli and L. casei. Conclusion: CDPG can be potentially used as an antibacterial and an antibiofilm agent against oral biofilm-forming bacteria. [ABSTRACT FROM AUTHOR]

Using an emittance technique with a fast CO2 laser heating of glass samples, the high‐temperature absorption spectra in the near‐infrared region of ultrapure and colored (Co‐, Cu‐, Mn‐, and Ni‐doped) glasses are measured. The effects of higher glass temperatures on these absorption spectra are explained in the framework of the ligand field theory. Thus, the temperature‐dependent absorption bands of the previous transition metal ions are assigned to electronic transitions among the ligand field energy levels of these ions. In particular, spectral shifts, spectral broadening, and changes in absorption strength are ascribed to changes in the structural symmetry of the ionic sites in the glass matrix and to changes of the ligand field strength at increasing temperatures. Besides, the temperature‐dependent Rosseland mean absorptions of the sulfate fined soda lime silicate glass melts, colored with the previous transition metal ions, are derived from the absorption spectra. Combining all the data, semiempirical correlations are derived, which predict the Rosseland thermal radiation properties as a function of glass temperature and of glass redox chemistry. The latter property involves the temperature‐dependent concentration of the specific valency of the coloring ions, determined independently, e.g. by a Gibbs minimization redox calculation tool. [ABSTRACT FROM AUTHOR]

A series of phosphate glass with the following formulation was manufactured using the melt quenching procedure: 3As2O3 - 37PbO -- (60 -x) P2O5- x WO3, x = (0 ≤ x ≤ 5 mol. %). The glasses' physical and other structural characteristics were examined in depth. The basic structural properties of the materials were examined using a variety of characterization procedures, such as XRD and FT-IR. With increasing WO3 concentration, the phosphate network evolves, leading to depolymerization of the glass network, according to the FT-IR analysis. With increasing WO3, the physical, mechanical, and structural parameters were enhanced like glass density, longitudinal and shear speeds, and all elastic moduli. Because of P--O--W bonds in the glass network are stronger than P--O--P bonds, the radiation characteristics were enhanced as the content of WO3 increased. The interpretation of the parameters showed that the glass in the statement is an excellent candidate for photon shielding applications. [ABSTRACT FROM AUTHOR]

Phosphoric acid-based porous geopolymers were prepared by two different foaming agents (H2O2 and Al powder) with phosphoric acid as the activator. High-magnesium nickel slag (HMNS) and fly ash (FA) were the precursor combination. The effects of foaming agent types and contents on the properties of HMNS-FA-phosphate-based porous geopolymers were investigated in terms of dry density, pore structure, compressive strength, thermal conductivity, and water absorption. The phase was analyzed by x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). It was found that both foaming agents could successfully prepare porous geopolymers, and the compressive strength and dry density of porous geopolymers gradually decreased and the low-thermal conductivity and water absorption gradually increased with the increase in foaming agent content. The foaming agents formed porous structures inside porous geopolymers but did not affect the phases of geopolymerization reactions. This study demonstrates that both foaming agents can be used to prepare HMNS-FA-phosphate-based porous geopolymers for the application of phosphate-activated geopolymers in the direction of refractory materials. [ABSTRACT FROM AUTHOR]

This study evaluated the apical sealing ability and bioactivity of an experimental gutta-percha containing niobium phosphate bioglass. Thirty-six human premolars were endodontically prepared and divided into three groups: GPC—filling with conventional gutta-percha; GBC—filling with bioceramic gutta-percha (EndoSequence BC); GNB—filling with experimental gutta-percha containing niobophosphate. Teeth were stored in tubes containing 2 mL of simulated body fluid (SBF) solution in an oven for 30 days. Then, the samples were immersed in lanthanum nitrate solution and analyzed for apical nanoleakage (NI) with a scanning electron microscope (SEM/EDS) and transmission electron microscope (TEM). Gutta-percha specimens were immersed for 28 days (SBF) and analyzed in SEM/EDS and X-ray diffraction (XRD) to assess bioactivity. NI data originated from the SEM/EDS were analyzed using the Kruskal–Wallis test (α = 5%). NI data originated from TEM and bioactivity were descriptively reported. Statistical analysis did not detect a significant difference between groups (p = 0.13) for NI. In the bioactivity analysis, an abundant layer of hydroxyapatite was identified only in the surface of the GNB group samples. The gutta-percha containing niobophosphate bioglass promoted an apical sealing similar to EndoSequence BC, in addition to demonstrating bioactivity through the deposition of hydroxyapatite on the surface of the material after immersion in SBF. [ABSTRACT FROM AUTHOR]

In this review, some physical properties of organic-inorganic perovskites, elastomer blends and glass are discussed; the mechanical behavior, optical bandgap, vibrational spectroscopy and nanostructure of these materials are investigated. The study of the mechanical properties of elastomer blends uses the pulse excitation technique as it is non-contact, easy used and not affecting the sample, reliable, low cost, accurate and suiting a wide variety of rubbery materials and elastomers. The internal friction coefficient is obtained by mathematical analysis and shows as the concentration of N774 black increases the internal friction increases until 90 phr, followed by a sharp increase. This may be due to the enhancement of the aggregations formations, less occlude rubber, the active friction forces in the deagglomeration - agglomeration of the filler vanishing and the special characteristic of N774 black (large particle size and low tendency to form aggregations). The study of the optical bandgap of perovskites and glasses by Schuster-Kubelka-Munk (SKM) remission function is achieved. The studied samples of perovskites show a strong absorption at the UV-Vis light region, so this behavior may find attractive applications as visible light photocatalysis. While these study on ZnO doped phosphate glass system show optical energy gap decrease from 3.68 eV to 3.25 eV with the increasing ZnO content. This can be related to the gradual increase in number of non-bridging oxygen (NBO) atoms. Vibrational spectroscopy is an efficient method to assign the IR/Raman peaks to their modes in the molecule or a part of it. The partial symmetry and Omega-table enhance the group theory character table and correct the meaning of complex quantities in it. The study of nanostructure by X-ray diffraction patterns is useful to determine the crystalline size. More deep theoretical approaches refine the obtained size and show the micro-strain inside the nanoparticle. [ABSTRACT FROM AUTHOR]

The influence of Er3+ ions on the optical properties of phosphate glasses doped by a fixed concentration of Sm+3 ions had been investigated. Optical absorption studies were executed to estimate the energy gap and Urbach energy. Judd–Ofelt, J–O, model has been applied to the absorption peaks for Er3+ (4f11) transitions to determine the J–O intensity parameters Ωt (t = 2, 4, 6). Using the calculated J–O parameters, the radiative transition probabilities (Ar), Branching ratios (Br), and radiative lifetime (τr) of various excited states of Er3+ ion have been calculated. The studied photoluminescence spectra under an ultraviolet excitation wavelength (380 nm) showed several visible emission bands confirming the down-conversion process. Energy transfer (ET) from 4S3/2 (Er3+) to 4G5/2 (Sm+3) was affirmed. An intensive green emission peak due to 4S3/2 → 4I15/2 transition had been observed with stimulated emission cross-section of 7 × 10–21 cm2. [ABSTRACT FROM AUTHOR]

A new series of (X) Na2O.(0·5−x)Fe2O3.(0·5)B2O3 of sodium and iron oxides doped borate glasses were synthesised by melt quenching. The bulk density, structural and temperature dependent electrical properties of these glasses have been investigated. The density decreased with increase in Na2O content up to Na2O=0·2 and increased thereafter. The FTIR studies indicated the presence of BO3 and BO4 groups in the network and also has shown presence of minimum NBOs at x=0·2. These results are attributed to the significant structural modifications taking place in the glass network at Na2O=0·20. The dc electrical conductivity decreased with increase in Na2O content up to Na2O=0·20 and increased for further addition of Na2O. The activation energy has increased up to 0·2 mol% of Na2O and decreased thereafter. Based on these results, it is established that at x=0·20, a changeover of dc conduction mechanism predominantly from polaronic to ionic is taking place. Mott’s SPH, Mott’s VRH and Greave’s VRH models have been used to explain the high and low temperature conductivities. [ABSTRACT FROM AUTHOR]

Among the different fundamental aspects that govern the design and development of elongated multimaterial structures via the preform-to-fiber technique, material association methodologies hold a crucial role. They greatly impact the number, complexity and possible combinations of functions that can be integrated within single fibers, thus defining their applicability. In this work, a co-drawing strategy to produce monofilament microfibers from unique glass-polymer associations is investigated. In particular, the molten core-method (MCM) is applied to several amorphous and semi-crystalline thermoplastics for their integration within larger glass architectures. General conditions in which the MCM can be employed are established. It is demonstrated that the classical glass transition temperature compatibility requirements for glass-polymer associations can be overcome, and that other glass compositions than chalcogenides can be thermally stretched with thermoplastics, here oxide glasses are considered. Composite fibers with various geometries and compositional profiles are then presented to illustrate the versatility of the proposed methodology. Finally, investigations are focused on fibers produced from the association of poly ether ether ketone (PEEK) with tellurite and phosphate glasses. It is demonstrated that upon appropriate elongation conditions, the crystallization kinetics of PEEK can be controlled during the thermal stretching and crystallinities of the polymer as low as 9 mass. % are reached in the final fiber. It is believed such novel material associations as well as the ability to tailor material properties within fibers could inspire the development of a new class of hybrid elongated objects with unprecedented functionalities. [ABSTRACT FROM AUTHOR]

The Bi2O3-B2O3-CaF2-EuF3 (BiBCEu) glass and glass–ceramics were prepared by controlled heat treatment method for orange-red laser sources and characterized through X-ray diffraction, Fourier transform infrared, Raman, transmission electron microscopy, photoluminescence excitation, emission and luminescence decay studies. Up on 396 nm excitation, the BiBCEu glass–ceramics containing Bi3B5O12 and CaF2 nanocrystallites exhibit an enhanced orange-red luminescence through Eu3+:5D0 → 7F2 (616 nm) transition. The radiative parameters such as radiative emission probability rate (AR), luminescence branching ratio (βR) and radiative decay time (τR) were determined using the intensities of Eu3+: 5D0 → 7FJ (J = 1, 2, 4) emission transitions following the Judd–Ofelt theory. The chromaticity coordinates of BiBCEu glass–ceramic heat treated at 575 °C for 10 h are situated in the orange-red region of the CIE diagram. The BiBCEu glass–ceramic synthesized at 575 °C for 10 h has an excellent proficiency for solid state orange-red laser sources. [ABSTRACT FROM AUTHOR]

Encapsulation strategies can isolate the organic chromophores and prevent chemical or photochemical degradation. Inorganic transparent glass matrix has excellent utility as encapsulation matrices. Although the sol-gel method can make this encapsulation, the unclear sol-gel synthetic mechanism limits the synthesis of multi-component glass whose properties can be modified. A novel technique to encapsulate organic chromophores within multi-component glasses is required. In this letter, an organic chromophore was successfully encapsulated within a multi-component glass matrix by spark plasma sintering (SPS). The glass composite has great chemical and photochemical stability. Besides, a non-radiative energy transfer process between rare earth ions and organic chromophores was observed in the glass composites. These results indicate that the glass composite has great potential for optical application, and SPS can be a novel technique for encapsulating organic chromophores. [ABSTRACT FROM AUTHOR]

A red emissive ruthenium(II) complex 1[PF6]2 of an amino ethanol substituted 1,10-phenanthroline-based ligand (L1) has been developed and characterized by spectroscopic analysis and single-crystal X-ray diffraction. Complex 1 shows an aggregation-induced emission (AIE) enhancement and forms nano-aggregates in the poor solvent water and highly dense polyethylene glycol (PEG) media. The possible reason behind the AIE properties may be the rigidity gained through weak supramolecular interactions between neighbouring phenanthroline ligands and PF6− counterions. The AIE properties were supported by UV-vis and photoluminescence (PL) spectroscopy and dynamic light scattering (DLS) studies to substantiate the formation of nano-aggregates and to understand the morphology of the aggregated particles, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies were performed. Compound 1[PF6]2 was highly selective towards pyrophosphate ions (PPi) over other phosphates such as ATP, ADP, AMP and H2PO4− ions and other competitive anions in the PL spectroscopic channel in acetonitrile. The PL titrations of 1[PF6]2 with PPi in CH3CN furnished the association constant Ka = 1.08 × 104 M−1 and the detection limit was calculated as low as 1.54 μM. The PPi detection has been established through the unique H-bonding interaction, supported by 1H NMR titration. Finally, the cytotoxicity study and bioimaging were carried out for biological application. The complex shows very low cytotoxicity and good biocompatibility and is suitable for intracellular PPi imaging. [ABSTRACT FROM AUTHOR]

Alkali metal salts usually have high melting points due to strong electrostatic interactions and solvents are needed to create ambient temperature liquid electrolytes. Here, we report on six phosphate-anion-based alkali metal salts, Li/Na/K, all of which are liquids at room temperature, with glass transition temperatures ranging from −61 to −29 °C, and are thermally stable up to at least 225 °C. While the focus herein is on various physico-chemical properties, these salts also exhibit high anodic stabilities, up to 6 V vs. M/M+ (M = Li/Na/K), and deliver some battery performance – at elevated temperatures as there are severe viscosity limitations at room-temperature. While the battery performance arguably is sub-par, solvent-free electrolytes based on alkali metal salts such as these should pave the way for conceptually different Li/Na/K-batteries, either by refined anion design or by using several salts to create eutectic mixtures. [ABSTRACT FROM AUTHOR]

This paper contains the design of active optical lenses used for the detection of arc flashing emissions. The phenomenon of an arc flashing emission and its characteristics were contemplated. Methods of preventing these emissions in electric power systems were discussed as well. The article also includes a comparison of commercially available detectors. An analysis of the material properties of fluorescent optical fiber UV-VIS-detecting sensors constitutes a major part of the paper. The main purpose of the work was to make an active lens using photoluminescent materials, which can convert ultraviolet radiation into visible light. As part of the work, active lenses with materials such as Poly(methyl 2-methylpropenoate) (PMMA) and phosphate glass doped with lanthanides, such as terbium (Tb3+) and europium (Eu3+) ions, were analyzed. These lenses were used to make optical sensors, which were supported by commercially available sensors in their construction. [ABSTRACT FROM AUTHOR]

The thermoluminescence (TL) dosimetric properties of metaphosphate glass system were investigated. The glass system of (Er2O3)1-(SrO)24-(B2O3)25-(P2O5)50 was prepared using a melt quenching technique. The glass system was characterized using different techniques. The internal structure of the system was probed with XRD and FTIR technique was used to identify the types of bonds between the involved atoms. The analysis of TL glow curve was studied by different methods and was found to be composed of six trap peaks at energies 0.817, 0.846, 0.958, 1.190, 1.248, and 1.347 eV. The TL dose–response signal was found to be linear in the range of 0.22–55 Gy. The activation energies were determined by three methods: glow curve deconvolution (CGCD), Tmax-Tstop method and Peak shape (PS) methods. The results of the three methods exhibited a good agreement with each other. Highlights The thermoluminescence properties of metaphosphate glass were investigated. The glass samples were irradiated to different doses of beta particles. The deconvolution indicated the presence of six overlapping glow peaks. The activation energies were determined by three methods and the results of all the methods exhibited a good agreement. [ABSTRACT FROM AUTHOR]

Phosphate glasses are characterized by properties distinguished by comparison with those of others such as borates, silicates, and tellurides that can be used in many fields such as optics, electronics, medicine, environmental protection, etc. This study aims to discover the effect of the europium dopant on the structural properties of glasses with 65% P2O5 – (35-x) % SrO – x% Eu3O2 (where x = 0.5, 1, 1.5, 2 mol at. %) using molecular dynamics simulations. The density of simulated glasses was found to increase from 2.784 to 2.860 g/cm3 according to the gradual increase in the europium content. The Eu-O distances and coordination numbers are found to be in the ranges of 2.18–2.21 Å and 6.59–6.79, respectively. The Sr-O coordination numbers were found to decrease from 7.30 to 6.55 with an increase in the europium content in the phosphate glasses. The coordination of the Eu-Eu pair increases from 0.07 to 0.23 with increasing europium concentration in phosphate glasses, but it remains weak, which is a sign of good solubility of europium in the glass matrix, as expected by experiments and the literature. Studies of the cluster statistics in the simulated glasses demonstrate that most europium atoms are found isolated or in a doublet. [ABSTRACT FROM AUTHOR]

Zinc selenium phosphate glasses added with the traces of Au2O3 were prepared and heat-treated. XRD, TEM, DSC, FT-IR and optical absorption (OA) spectroscopy methods were used for the structural assessment of these samples. Later, different dielectric parameters viz., dielectric constant (ε′), electric moduli (M), impedance (Z) and a.c. conductivity (σac) were measured over wide regions of frequency (ω) and temperature (T) as functions of Au2O3 concentration. Dielectric breakdown strength (DBS) of these samples was also measured at ambient conditions. The characterization studies indicated that multiple crystal grains were entrenched in the residual amorphous phase of the samples. The X-ray diffraction studies revealed that the bulk glasses consisted of Au2(SeO3)3 crystal phase and Au0 metallic particles (MPs). As Au2O3 content was raised, the intensity of the XRD peak related to Au3+ crystal phase indicated a growing trend, whereas that of Au0 MPs showed a decreasing trend. The results of XPS studies revealed similar inferences. The FT-IR results pointed out an improved degree of augmentation of the glass network as the content of Au2O3 was increased. Optical absorption (OA) - spectra of the glasses indicated a broad absorption band in the spectral range of 500–600 nm due to the surface plasmon resonance (SPR) of Au0 MPs. The intensity of the band was observed to decrease as Au2O3 content was increased and indicated decreasing proportion of Au0 metallic particles in the samples. The dielectric parameters exhibited a decreasing trend, whereas the dielectric breakdown strength (DBS) and electrical impedance indicated a substantial hike due to the increasing concentration of Au2O3. Overall, the presence of Au2O3 caused a significant improvement in the insulating strength of the ZnO added SeO2-P2O5 glasses and hence such glasses may be considered as insulating layers in the display panel devices. [ABSTRACT FROM AUTHOR]

In numerous tissue engineering and dental applications, bioactive glasses are utilized. These glasses have unique characteristics that make them attractive candidates for a variety of applications. A new bioactive glass system with the structure of 45P2O5 -- 20CaO -- 15CaCL2 -- 8KF -- (10 -- x) Li2O -- (x) TiO2 was developed in this study, with x = 2, 6, and 8 mol%. For usage in radiation protective applications, it was evaluated. By using an ultraviolet-visible spectrophotometer, we were able to measure the absorbance (Abs) and transmittance (T %) in the range of wavelengths 190-2500 nm. Furthermore, the optical energy gap of the produced glasses was determined. Using the MIKE software, the mass attenuation coefficients (MAC) of the bioactive glasses under investigation were calculated for energies ranging from 15 to 200 keV. The LAC, Zeff, Neff, HVL, TVL, and MFP (Linear attenuation coefficient, effective atomic number, effective electron density, half value layer, tenth value layer, and mean free path) of the bioactive glasses were calculated. According to the findings, the addition of titanium dioxide (TiO2) as well as the metal oxide such as Li2O to bioactive glasses generates significant differences in the attenuation characteristics of bioactive glasses. The results indicate that the PCKLT3(TiO2= 8mol%) bioactive-glass sample had the best attenuation among other samples. [ABSTRACT FROM AUTHOR]

The purpose of this in vivo study was to evaluate and compare the dentin–pulp complex response following occlusal and cervical restorations in rat molars restored with nano-hydroxyapatite silica glass ionomer cement (nano-HA-SiO2-GIC) and conventional glass ionomer cement (c-GIC). In total, 64 maxillary first molars of 32 male Wistar rats were restored using Fuji IX (c-GIC) and nano-HA-SiO2-GIC using a split-mouth design. Half of them were reserved for the occlusal type of restoration while the other half was for cervical restorations. After one week and one month, rats were euthanized and were stained with hematoxylin and eosin, Masson's trichrome, and Brown and Brenn techniques for histological examination. Parameters such as disorganization of the pulp tissue, inflammatory cell infiltration, detection of bacteria, and tertiary dentin deposition were measured for each group. One week after sacrifice, the odontoblastic layer was disrupted, and moderate inflammation in the pulp area close to the cut dentin was observed in both types of restorations. Nano-HA-SiO2-GIC showed significantly superior properties when assessed based on tertiary dentin formation as compared to c-GIC. One month after sacrifice, there was no evidence of disruptions of the odontoblast layer, which exhibited a normal palisade appearance in both groups. In terms of inflammation, the pulp tissue recovered in almost all cases except one of c-GIC, but a few cases of the nano-HA-SiO2-GIC group still displayed mild-to-moderate inflammatory reactions, especially of the occlusal type. Both c-GIC and nano-HA-SiO2-GIC exhibited favorable responses in terms of biocompatibility. Nano-HA-SiO2-GIC exerted more inflammation but encouraged better tertiary dentin formation compared to c-GIC. [ABSTRACT FROM AUTHOR]

A thorough analysis of glass containing Eu2O3 and Dy2O3, or Eu2O3, Dy2O3, and CuO melted together with nanodiamond powder was pursued based on measurements of optical absorption, photoluminescence (PL) emission and excitation spectra, and colorimetry. Nanodiamond facilitated the stabilization of Cu+ and Eu2+ ions with blue‐emitting characteristics that, along with yellow‐emitting Dy3+ and red‐emitting Eu3+ led to the white light‐emitting glass. Novel intensity notations implemented in intensity‐based spectral ratios, and difference intensity correlation analysis were proposed for the assessment of PL properties. The chromaticity and correlated colour temperature of the emission were ultimately investigated as a two‐parametric problem based on: (1) the different ionic components; and (2) the various excitation wavelengths employed. The optical analysis approach adds to the characterization methods to further fundamental understanding and provide helpful analytical tools for designing materials for tunable white light‐emitting devices. [ABSTRACT FROM AUTHOR]

Dynamic light scattering was performed to measure the structural relaxation in sodium and zinc phosphate glass-forming melts in the range from 50 mol% to 40 mol% P2O5 where long polymer-like chains of PO4 tetrahedra are systematically shortened in length. The findings reveal compositional changes in the non-exponentiality of the relaxation as well as in the glass fragility, the latter of which exhibits anomalous differences between sodium and zinc.

In the current research, the binary solution containing ionic liquid (IL), 1-ethyl-1-methylmorpholinium dimethyl phosphate ([C1C2MOR][DMP]), 1-ethyl-1-methylpiperidinium dimethyl phosphate ([C1C2PIP][DMP]), or N,N,N-triethyl-N-methylammonium dimethyl phosphate ([N1,2,2,2][DMP]) with ethanol are investigated as new working fluids for absorption refrigeration technology. The IL was mixed with ethanol, which was considered as a refrigerant. Experimental (vapor + liquid) phase equilibria (VLE) of these binary systems were 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 were correlated using non-random two-liquid (NRTL) within the maximum average relative deviation of 0.45%, which confirms the effectiveness of using such a model for calculations. Each of the proposed binary systems exhibit a negative deviation from Raoult's law, which is a very important characteristic for working pairs used in absorption heat pumps or absorption refrigerators. From a technological point of view, measurements of physicochemical properties play an important role. In this research, liquid density and dynamic viscosity were determined at temperatures from T = (293.15 to 338.15) K at ambient pressure over the whole concentration range. These properties were correlated using empirical equations. From experimental density data, the excess molar volumes were determined and correlated using the Redlich–Kister type equation. Ionic liquid: [C1C2MOR][DMP] and [C1C2PIP][DMP] were synthesized and characterized using NMR analysis. The thermophysical characterization of pure ILs, including glass transition temperature (Tg) and heat capacity at the glass transition temperature (ΔgCp), was determined using the differential scanning calorimetry technique (DSC) at atmospheric pressure. In this work, the combination of basic studies on the effect of the cation structure of an ionic liquid on the properties of their solutions with ethanol and the possibility of future application of the tested systems in a viable refrigeration system are presented. [ABSTRACT FROM AUTHOR]

Nd3+-doped GeO2-PbO glass with silver (Ag) nanoparticles (NPs) are produced with double line waveguides through fs laser processing for photonic applications. A Ti:sapphire fs laser at 800 nm was used to write the waveguides directly into the glass 0.7 mm beneath the surface. This platform is based on pairs of parallel lines with spacing of 10 µm, each pair being formed by two identical written lines but in two different configurations of 4 or 8 separately processed lines, which are coincident. The results of optical microscopy, absorbance measurements, refractive index change, beam quality factor (at 632 and 1064 nm), photoluminescence, propagation losses, and relative gain at 1064 nm are presented. The structural changes in the glass due to the presence of Ag NPs were investigated by Raman spectroscopy. At 632 and 1064 nm, x,y-symmetrical guiding was observed, and for both kinds of overlapping pulses, a refractive index alteration of 10−3 was found in both directions. Photoluminescence growth of ~47% at 1064 nm was observed due to the plasmonic effect of Ag NPs. In dual waveguides containing Ag NPs, the relative gain obtained increased by 40% and 30% for four and eight overlapping lines, respectively, at 600 mW of 808 nm pump power, when compared to waveguides without those metallic NPs. We highlight the resultant positive internal gains of 5.11 and 7.12 dB/cm that showed a growth of ~40% and ~30%, respectively, with respect to the samples without Ag NPs. The increase in photoluminescence and relative gain were related to the local field growth produced by Ag NPs. The present results show that the addition of Ag NPs impacts positively on the optical performance at 1064 nm of double line waveguides processed by fs laser writing in Nd3+-doped GeO2-PbO glass, opening news perspectives for photonics. [ABSTRACT FROM AUTHOR]

The main purpose of the research was to explain the differences between nominal and actual chemical compositions of silicate-phosphate glasses in the SiO2-P2O5-K2O-MgO-SO3 system. The actual compositions of the materials were determined with X-ray fluorescence (XRF) analyses. Changes in the chemical composition were explained by examining the melting processes for selected glass batches with differential scanning calorimetry-thermogravimetry-related gas analysis by mass spectrometry (DSC-TG-EGA (MS)) and high-temperature X-ray diffraction (HT-XRD). It was found that changes in the chemical composition of the sulfur-bearing glasses were associated with the release of gaseous products. The main gases released during thermal decomposition of the selected glass batch were water vapor, carbon dioxide, carbon monoxide, and ammonia. Since these glasses have potential for use as glassy fertilizers, there is no doubt that the present study is important from an environmental point of view. [ABSTRACT FROM AUTHOR]

The present study provides a deep insight into the implications of sulphate addition on glass forming properties of materials from the SiO2–P2O5–K2O–MgO/CaO/MgOCaO systems, by combining: preliminary investigation of as-synthesized materials (XRD, XRF, SEM–EDS), detailed characteristics of their thermal behaviour (DSC), estimation of various glass-stability parameters, in-depth analysis of the course of crystallization and an identification of the crystallized products (XRD, Raman imaging technique). Performed investigations revealed that obtaining amorphous materials is only possible in the system containing MgO as a alkaline earth glass modifier, whereas melts of other tested compositions display high tendency to crystallize during cooling. Thermal investigation showed that the influence of SO3 addition on thermal properties of studied materials strongly depends on their composition, but generally such additive increased values of glass transformation temperature and decreased vitreous state transformation range and onset of the crystallization process, compared to the base samples, which is a signal of decrease in thermal stability. Examination of devitrificates revealed the character and distribution of domains present in the structure of studied materials. It was showed that irrespective of composition of the base glass, it is K2SO4 that precipitates once the sulphate capacity of glass is exceeded and exists in the studied materials as groupings either distributed in the voids of silicate phase, or surrounding the remnants of the gas bubbles embodied within the glass body. The results demonstrated in the present study provide guiding suggestions for development of SO3-containing silicate–phosphate glasses intended especially for applications where release of bioactive ions is sought. [ABSTRACT FROM AUTHOR]

Multicomponent cobalt phosphate–silicate glasses from P2O5–SiO2–K2O–MgO–CaO–Co2O3 system in which molar ratio of P2O5 to SiO2 is 41:6 and cobalt ions are gradually incorporated at the expense of magnesium and calcium ions were prepared via melt-quenched technique. The obtained amorphous solids were subjected to the thermal and spectroscopic studies and density measurements in order to gain information about the structure and physical properties. As DSC, XRD, FTIR and pycnometry techniques were applied, the glass transition temperature, specific heat change, crystallization temperature, density, molar volume, oxygen packing density and associated infrared spectra were collected for each glass. Then, the process of induced crystallization was performed on the selected glass samples. The related glass-crystalline materials were evaluated via XRD method. As a result, crystalline phases associated with crystallization temperature were identified. The alterations in determined parameters, stoichiometry of connected crystalline phases and features of infrared spectra allow to conclude the impact of cobalt ions on structure of analyzed glasses due to the direct dependence of structure, physical and thermal properties. The conducted research constitutes a basis for further analysis of cobalt phosphate–silicate glasses and makes a contribution to the knowledge concerning the phosphate glasses family. [ABSTRACT FROM AUTHOR]

Through theoretical analysis and finite element simulation experiments, this paper proposes an optimal design method for the structural parameters of ceramic tools with variable cross-sections. On this basis, the tool angles of Si 3 N 4 -based ceramic tools for cutting inconel 718 high-temperature alloy are investigated, including rake angle γ 0 = −5°, clearance angle α 0 = 5°, cutting edge inclination λ s = −2°, cutting edge angle K r = 45°. By comparing the main cutting force, temperature and chip-breaking effect of flat face and three different groove ceramic tools, it is found that straight chip breaker has the most obvious optimization effect, main cutting force is 14.5% lower than that of the flat face, the temperature is reduced by 10.2%, and radius of chip curl curvature is the smallest, which is easy to break chips. [ABSTRACT FROM AUTHOR]

137Cs is a major element in radioactive waste of nuclear power plant and there have been numerous reports on immobilization of 137Cs in the crystalline structure of pollucite (CsAlSi 2 O 6). In this work, Cs-polluted soil (metakaolin) and a specially formulated phosphate glass were sintered together to form a CsAlSi 2 O 6 -based glass-ceramic. Extensive experiments and characterizations by XRD, DSC, SEM, and EDS allowed optimum glass addition to be established. The formation temperature of CsAlSi 2 O 6 in the glass matrix was approximately 900 °C, significantly lower than those used in forming Cs-pollucite by conventional sintering methods. Raman spectroscopy and SEM studies confirmed that Cs+ was immobilized in the crystalline structure of CsAlSi 2 O 6 and further, CsAlSi 2 O 6 crystals were encapsulated in the glass matrix. When the addition of phosphate glass was 10 wt%, the leaching rate was lowest (3.35 × 10-4 g m-2 d-1) and the bending strength was the highest (30 MPa). We believe that this study offers a potential alternative and some useful data for safe processing of radioactive waste at a relatively low temperature. [ABSTRACT FROM AUTHOR]