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Metallic (Cu m)n+ nanoclusters are superior to their (Au m)n+ and (Ag m)n+ counterparts in the aspect of being relatively cheap for wide industrial demands. However, further improvements are still needed, especially in terms of the generation of (Cu m)n+ nanoclusters. Herein, (Cu m)n+ has been successfully generated with Mn2+ ions into 2.5MnO·47.5Li 2 O·50P 2 O 5 (MnP), 2.5CuO·47.5Li 2 O·50P 2 O 5 (CuP) and 2.5MnO·2.5CuO·45Li 2 O·50P 2 O 5 (CuMnP) matrices. This generation has been demonstrated by XRD, XPS, TEM, SEM, AFM, UV–Vis and PL analyses. MnP displays an amorphous nature with red light emission under an excitation wavelength of 409 nm due to the 4T 1 (G)→6A 1 (S) transition of Mn2+ ions. CuP and CuMnP exhibit the formation of spherical nanoclusters with a size less than 10 nm. These nanoclusters are attributed to (Cu m)n+, which exhibit tunable emission from blue to white to red light as the excitation wavelength changes from 270 to 360 nm. When MnP, CuP and CuMnP are subjected to 380 °C for 4, 1 and 1 h, respectively, the LiPO 3 crystalline phase has evolved. This is associated with the reduction of (Cu m)n+ to plasmonic (Cu°) n nanoparticles, and therefore crystallization-induced photoluminescence weakening. This demonstrates that the lithium metaphosphate glassy matrix provides an efficient emission as compared to the corresponding LiPO 3 crystalline phase. Overall, in the CuMnP matrix, there is an efficient energy transfer from (Cu m)n+ to Mn2+ as the 1E g excited level of (Cu m)n+ is higher than the 4A 1 /4E energy levels of Mn2+ ions. This synergistic Mn2+/(Cu m)n+ combination has resulted in the generation of a rare earth-free platform promised for white LED applications. [ABSTRACT FROM AUTHOR]

Studies into the biology of condensed phosphates almost exclusively cover linear polyphosphates. However, there is evidence for the presence of cyclic polyphosphates (metaphosphates) in organisms and for enzymatic digestion of branched phosphates (ultraphosphates) with alkaline phosphatase. Further research of non‐linear condensed phosphates in biology would profit from interactome data of such molecules, however, their stability in biological media is limited. Here we present syntheses of modified, non‐hydrolysable analogues of cyclic and branched condensed phosphates, called meta‐ and ultraphosphonates, and their application in a chemical proteomics approach using yeast cell extracts. We identify putative interactors with overlapping hits for structurally related capture compounds underlining the quality of our results. The datasets serve as starting point to study the biological relevance and functions of meta‐ and ultraphosphates. In addition, we examine the reactivity of meta‐ and ultraphosphonates with implications for their "hydrolysable" analogues: Efforts to increase the ring‐sizes of meta‐ or cyclic ultraphosphonates revealed a strong preference to form trimetaphosphate‐analogue structures by cyclization and/or ring‐contraction. Using carbodiimides for condensation, the so far inaccessible dianhydro product of ultraphosphonate, corresponding to P4O112−, was selectively obtained and then ring‐opened by different nucleophiles yielding modified cyclic ultraphosphonates. [ABSTRACT FROM AUTHOR]

The article presents the study results of new inorganic binders and the physicochemical processes of their formation. The main purpose of the created materials is to make molds and cores for foundry production. Creating environmentally-friendly binders with a set of functional properties for foundry production is relevant worldwide. Therefore, scientists from different countries are paying special attention to the study of silicate and phosphate binders. The study analyzes the kinetics of the orthophosphoric acid interaction with several inorganic materials – pulverent pyrophyllite, disthene-sillimanite, a by-product of electrocorundum production, and sodium chloride. The phase and chemical composition of all formed binders have been established. In aluminum-containing compositions, those are represented by aluminum orthophosphates in crystalline and amorphous forms. Sodium metaphosphate is formed in the composition with sodium chloride. Peculiarities of the structuring compositions physical process with liquid glass and granular quartz filler due to steam-microwave treatment are determined. It is shown that structuring occurs due to dehydration, which is completed within 4…12 min, which allows reducing the liquid glass content in the composition to 1.5% while ensuring a high level of strength. The properties of structured compositions with the developed binding components are researched, and it is shown that all of them are competitive. Recommendations for their possible application were created.

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]

Today, the most common way of laser sealing is using a glass frit paste and screen printer. Laser sealing using glass frit paste has some problems, such as pores, nonuniform height, imperfect hermetic sealing, etc. In order to overcome these problems, sealing using fiber types of sealant is attractive for packaging devices. In this work, (70-x)V2O5-5ZnO-22BaO-3B2O3-xM(PO3)n glasses (mol%) incorporated with xM(PO3)n concentration (where M = Mg, Al, n = 2, 3, respectively) were fabricated and their thermal, thermomechanical, and structural properties were investigated. Most importantly, for this type of sealing, the glass should have a thermal stability (ΔT) of ≥80 °C and the coefficient of thermal expansion (CTE) between the glass and panel should be 1.0 ppm/°C. The highest thermal stability ΔT of the order of 93.2 °C and 112.9 °C was obtained for the 15 mol% of Mg(PO3)2 and Al(PO3)3 doped glasses, respectively. This reveals that the bond strength and connectivity is more strongly improved by trivalent Al(PO3)3. The CTE of a (70-x)V2O5-5ZnO-22BaO-3B2O3-xAl(PO3)3 glass system (mol%) (where x = 5–15, mol%) is in the range of 9.5–15.5 (×10−6/K), which is comparable with the CTE (9–10 (×10−6/K)) of commercial DSSC glass panels. Based on the results, the studied glass systems are considered to be suitable for laser sealing using fiber types of sealant. [ABSTRACT FROM AUTHOR]

How life began still eludes science life, the initial progenote in the context presented herein, being a chemical aggregate of primordial inorganic and organic molecules capable of self-replication and evolution into ever increasingly complex forms and functions. Presented is a hypothesis that a mineral scaffold generated by geological processes and containing polymerized phosphate units was present in primordial seas that provided the initiating factor responsible for the sequestration and organization of primordial life's constituents. Unlike previous hypotheses proposing phosphates as the essential initiating factor, the key phosphate described here is not a polynucleotide or just any condensed phosphate but a large (in the range of at least 1 kilo-phosphate subunits), water soluble, cyclic metaphosphate, which is a closed loop chain of polymerized inorganic phosphate residues containing only phosphate middle groups. The chain forms an intrinsic 4-phosphate helix analogous to its structure in Na Kurrol's salt, and as with DNA, very large metaphosphates may fold into hairpin structures. Using a Holliday-junction-like scrambling mechanism, also analogous to DNA, rings may be manipulated (increased, decreased, exchanged) easily with little to no need for additional energy, the reaction being essentially an isomerization. A literature review is presented describing findings that support the above hypothesis. Reviewed is condensed phosphate inorganic chemistry including its geological origins, biological occurrence, enzymes and their genetics through eukaryotes, polyphosphate functions, circular polynucleotides and the role of the Holliday junction, previous biogenesis hypotheses, and an Eoarchean Era timeline. [ABSTRACT FROM AUTHOR]

In this work, the core-shell structured Ni(OH) 2 /Ni(PO 3) 2 (NNP) hybrid composite grown in situ on Ni foam was synthesized by a one-step electrodeposition. The as-obtained NNP nanosheets was used as positive electrode to assemble asymmetric supercapacitor, which exhibited high energy density of 67 Wh kg−1 at power density of 775 W kg−1 and long cycle life in 2 M KOH electrolyte. • The core-shell structured NNP electrode is prepared by one-step deposition method. • The synergy effect of core-shell structure achieves remark electrochemical performances. • The as-assembled NNP//rGO ASC exhibits a high energy density and long cycle life. Metal metaphosphates, particularly those with core-shell structure, have showed extraordinary potential in energy storage field due to their superior chemical and physical properties. However, the core-shell metal metaphosphates with high energy density in supercapacitor application is rarely reported. Here, the core-shell structured Ni(OH) 2 /Ni(PO 3) 2 (NNP) hybrid electrode were prepared by one-step electrodeposition, which exhibits a superior specific capacitance of 1477 F g−1 at a current density of 1 A g−1. Furthermore, an aqueous asymmetric supercapacitor (ASC) based on NNP hybrid composite as cathode and reduced graphene oxide (rGO) as anode is assembled successfully to deliver a prominent energy density of 67 Wh kg−1 at 775 W kg−1 and splendid stability with capacitance retention of 81% after 8000 cycles. The outstanding electrochemical capabilities are attributed to the porous nanoflake and hierarchical core-shell structure of NNP hybrid composite, which can accelerate ion diffusion and charge transfer in redox reaction. These results indicate that nanohybrid NNP material has promise to be an advanced energy storage material. [ABSTRACT FROM AUTHOR]

The monoclinic α-polymorph of (VIVO)(PO3)2 is obtained reproducibly by reaction of V2O5 and H3PO4 (85%) (Au crucible, 380 °C, 4 d). Its crystal structure was refined from X-ray single-crystal data [C2/c, Z = 4, a = 15.1038(7) Å, b = 4.193(2) Å, c = 9.573(9) Å, β = 126.45(3), R1 = 0.052, wR2 = 0.189 for 976 unique reflections with Fo > 4σ(Fo), 48 variables]. A single-phase powder of the β-polymorph is obtained by the reaction of V2O5, H3PO4 (85%) and oxalic acid, evaporating the mixture, and subsequent annealing (porcelain crucible, 800 °C in air, 2 d). Single crystals of β-(VIVO)(PO3)2 were grown in a sealed silica ampoule with chlorine as mineralizer. The crystal structure of the orthorhombic (pseudo-tetragonal) β-polymorph was refined from X-ray single-crystal data [pseudo-merohedral twin, Fdd2, Z = 8, a = 15.536(2) Å, b = 15.586(2) Å, c = 4.2611(5) Å, R1 = 0.032, wR2 = 0.068 for 1072 unique reflections with Fo > 4σ(Fo), 50 variables]. Earlier reports on a tetragonal polymorph with unusual geometric structure of the [(V≡O)O5] polyhedron are corrected. [ABSTRACT FROM AUTHOR]

Today, the most common way of laser sealing is using a glass frit paste and screen printer. Laser sealing using glass frit paste has some problems, such as pores, nonuniform height, imperfect hermetic sealing, etc. In order to overcome these problems, sealing using fiber types of sealant is attractive for packaging devices. In this work, (70-x)V2O5-5ZnO-22BaO-3B2O3-xM(PO3)n glasses (mol%) incorporated with xM(PO3)n concentration (where M = Mg, Al, n = 2, 3, respectively) were fabricated and their thermal, thermomechanical, and structural properties were investigated. Most importantly, for this type of sealing, the glass should have a thermal stability (ΔT) of ≥80 °C and the coefficient of thermal expansion (CTE) between the glass and panel should be 1.0 ppm/°C. The highest thermal stability ΔT of the order of 93.2 °C and 112.9 °C was obtained for the 15 mol% of Mg(PO3)2 and Al(PO3)3 doped glasses, respectively. This reveals that the bond strength and connectivity is more strongly improved by trivalent Al(PO3)3. The CTE of a (70-x)V2O5-5ZnO-22BaO-3B2O3-xAl(PO3)3 glass system (mol%) (where x = 5–15, mol%) is in the range of 9.5–15.5 (×10−6/K), which is comparable with the CTE (9–10 (×10−6/K)) of commercial DSSC glass panels. Based on the results, the studied glass systems are considered to be suitable for laser sealing using fiber types of sealant.

We have employed the solid-state chemical reaction to construct series of trivalent erbium ions activated NaLaP 4 O 12 (abbreviated as: NLP) phosphors. The structural investigation indicates that NLP:Er3+ crystalline products are purely monoclinic phase with micron particles. Trivalent erbium ions with the substitution for lanthanum are successfully inserted into NLP host lattice. The UV–Vis diffuse reflectance absorption performance, doping Er3+ content-dependent downconversion photoluminescence, content quenching mechanism were reported in this paper. Upon near UV (378 nm) excitation, yellow/yellow-green visible light with the dominant 4S 3/2 → 4I 15/2 emission of trivalent erbium is displayed. Yellow-green emitting NLP:2%Er3+ sample has the maximum intensity and main luminescent peaks at 541 and 549 nm. The content quenching is related to the dipolar interaction. Additionally, the detailed investigation on CIE chromaticity coordinates, CP and CCT reveals that the title product has promising application in the field of white LEDs excited by near UV light. [ABSTRACT FROM AUTHOR]

Sodium cobalt metaphosphate [NaCo(PO3)3] has CoO octahedra (CoO6) and shows superior oxygen evolution reaction (OER) activity in alkaline solution, comparable with the state‐of‐the‐art precious‐metal RuO2 catalyst. OER catalysts of this metaphosphate are prepared by combustion (Cb) and solid‐state (SS) methods. The combustion‐assisted method offers a facile synthesis and one‐step carbon composite formation. Unusually high catalytic activity was observed in NCoM‐Cb‐Ar and could be due to chemical coupling effects between NaCo(PO3)3 and partially graphitized carbon. This novel electrocatalyst exhibits very small overpotential of 340 mV with high mass activity of 532 A g−1. Good charge transfer abilities and chemical coupling between NaCo(PO3)3 and amorphous carbon gives the OER activity in NCoM‐Cb‐Ar. [ABSTRACT FROM AUTHOR]

Phosphate based glasses 48P 2 O 5 —(32— x )CaO—20Na 2 O— x CaF 2 ( x  = 0, 1, 2, 3 and 4 mol%, hereafter, termed as FPG0, FPG1, FPG2, FPG3 and FPG4 respectively) with different fluoride content were prepared by keeping the ratio of P/Ca as 3. To study the influence of fluoride on the physico-chemical properties and bioactivity of phosphate based glasses, various experimental analysis such as density, elastic moduli, micro hardness, X-ray diffraction, scanning electron microscopy, Energy dispersive X-ray spectroscopy, cytotoxicity, pH variations during in vitro studies by soaking in simulated body fluid as a function of fluoride content were carried out. A variation in density, micro hardness and elastic moduli is noted for the glass samples as a function of its fluoride content. X-ray diffraction pattern, Fourier Transform Infra-Red spectra, scanning electron microscope images and energy dispersed X-ray spectra confirmed the fluoroapatite forming ability on all the fluoride added glass samples. The elastic moduli, microhardness, rich formation of FAp and non-toxic nature of glass sample FPG3 showed the better bioactivity than all the other samples. The observed cell growth of human osteoblast like cell lines proved the non-toxic nature of glass sample FPG3. Thus the observed results confirms the glass sample with 3 mol% of CaF 2 content is suitable for implant applications. [ABSTRACT FROM AUTHOR]

The rate of solvolysis of p-nitrophenyl phosphate (PNPP) dianion in DMSO/water strongly decreases by increasing water concentration. Addition of linear alcohols (methanol, propanol, butanol, pentanol, and hexanol) at constant DMSO/water molar ratio produced an even sharper rate decrease. Alkyl phosphate formation, resulting from PNPP solvolysis in ternary DMSO/water/alcohol mixtures, increased with alcohol concentration and was essentially temperature independent. Methanol and hexanol were the poorest nucleophiles under all conditions. Activation energies and enthalpies for solvolysis in ternary mixtures were similar and entropies varied with alcohol concentration. Taken together these results can be best interpreted in terms of a dissociative mechanism with the intervention of metaphosphate. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: The removal of orthophosphates (10−2 kg P m−3), condensed phosphates (10−2 kg P m−3), and mixtures of both (5 as orthophosphate and 5 as metaphosphate) in aqueous solution is studied using alum and aluminum hydroxide. The effects of coagulant dose, pH, temperature, aging of aluminum hydroxide, and presence of different ions are investigated. On the basis of the experimental results, alum is much more efficient in phosphorus removal than aluminum hydroxide even if, in both cases, at the conditions studied, the active coagulant form is Al(OH)3. The differences then could be due to the higher activity of the in situ formed hydroxide. Orthophosphates and metaphosphates seem to have similar behavior vs pH variation: maximum removal is achieved at pH values 5–6 in all cases. On the other hand, in the simultaneous presence of both P forms, orthophosphate and metaphosphate ions have different affinities for the surface sites of aluminum hydroxide, since for both alum and aluminum hydroxide, orthophosphates are preferentially removed compared to metaphosphates, due probably to orientation effects and the charge per P atom. The presence of sodium, potassium, magnesium, sulfate, chloride, and magnesium, at the concentrations studied and for a pH value of 6, does not influence P removal. Temperature variation, between 25 and 60 °C, does not affect alum efficiency but both P forms are increasingly removed with increasing temperature, probably due to polymer Al(OH)3 breaking, producing new surfaces for adsorption. Aging decreases sorption capacity of Al(OH)3, while crystallites of increasing size are formed. Finally adsorption of both P forms is best described by the Freundlich isotherm [, : 0.14–0.19 for ] and [, : 2.17–2.47 for ] for orthophosphate and metaphosphate, respectively. [Copyright &y& Elsevier]

Abstract: Potassium aluminum phosphate (KAP) glasses in the system xKPO3–(100− x)Al(PO3)3 with x =10, 30 and 50 mol% were prepared in the metaphosphate composition. The glasses were doped with MnO2 and their thermoluminescent (TL) response was investigated. Raman spectra showed that these glasses did not undergo structural changes with the substitution of manganese ions. The glass composition x =50mol% doped with 1.0mol% of MnO2 presented the best TL response. The material displayed good sensitivity for γ-rays, X-rays and UV light. The emission curves exhibited two TL peaks, one at a low temperature (∼150°C) and the other at a high temperature (∼365°C), whose positions were dependent on the type of exciting radiation applied. The results of the present study indicated that the high temperature peak is a good candidate for TL dosimetric investigations. [Copyright &y& Elsevier]

Abstract: From Raman and IR spectra, obvious differences of the glass structure were observed in non-Yb3+-doped and Yb3+-doped fluorophosphate glasses. Results showed that Yb3+ ions can induce, in a better glass, polymerization and network uniformity. Compared with the monophosphate-mastered Yb3+-free glass, Yb3+-doped glass has a pyrophosphate environment. The main building blocks in Yb3+-doped samples are metaphosphate groups, pyrophosphate groups (P2(O,F)7,PO3F), Al[F6]+Al[O,F]6 and F3Al–O–AlF3 while those of the Yb3+-free glasses are monophosphate groups P(O,F)4, little pyrophosphate groups, Al[F4]+Al[F6]+Al[O,F]4+Al[O,F]6 and F3Al–O–AlF3. The DSC analysis also showed a slight increase in crystallization stability. [Copyright &y& Elsevier]

• New boron-phosphate glass network was obtained by the introduction of Al(PO 3) 3 into boron oxide glass. • The structure of as-prepared glasses changed due to the reconstruction of glass network by [PO 4 units. • The transformation of glass network resulted in the redistribution of highly polarized ions and affecting the magneto-optical properties. • A new method to improve magneto-optical properties was proposed, instead of increasing the content of transition metal oxide and rare earth metal oxide. Herein, diamagnetic PbO–Bi 2 O 3 –B 2 O 3 –Al(PO 3) 3 glasses are prepared by melt-casting and the influence of phosphorus tetrahedral on the structure and optical properties of the glass has been systematically investigated. Compared to diamagnetic PbO–Bi 2 O 3 –B 2 O 3 (PBB) glasses, the original boron chain network has been replaced by the boron-phosphate structure. The metaphosphate forms [PO 4 units and expands the glass network, which leads to the decline of density and the increase of refractive index (up to ~2.423 @633 nm). The improvement of the magneto-optical properties performs in that the Verdet constant achieves 0.203 min/G cm at 633 nm and higher magneto-optical figure of merit displays a better optical performance than the diamagnetic glass without metaphosphate. [ABSTRACT FROM AUTHOR]

To promote the development of the solid state lighting and display industry, exploring excellent inorganic phosphors has been always a hot scientific and applied issue. Herein, we have constructed series of samarium activated sodium lanthanum metaphosphate NaLaP 4 O 12 (abbreviated as: NLP) phosphors via the high-temperature solid phase synthesis process. The crystalline phase composition, micromorphology, ionic valence states, diffuse reflectance absorption performance and concentration quenching mechanism were solved in detail. The photoluminescence excitation (PLE) and photoluminescence (PL) behavior of the as-prepared samples is closely dependent on the doping Sm3+ concentration. The optimized PL strategy is as following: the strongest excitation line is located at 401 nm, and the optimal doping concentration is 7 mol%. NLP:7%Sm3+ displays intense orange-red visible luminescence with the dominant 4G 5/2 → 6H 7/2 transitions located at 596 and 605 nm. The detailed investigation on CIE chromaticity coordinates, color purity (CP), correlated color temperature (CCT), internal quantum efficiency (IQE) and fluorescence lifetime suggests that we may use NLP:Sm3+ micropowder as alternative ingredient for phosphor-converted near UV-based warm white LEDs. Image 1 • First time, a detailed orange-red emitting study was carried out on Sm3+-activated NaLaP 4 O 12 (NLP) phosphor. • For Sm3+ doped concentration-dependent PLE and PL, the optimal doping concentration is 7 mol%. • NLP:7%Sm3+ orange-red phosphor with the 38.8% IQE and 1.66 ms lifetime exhibited high CP and low CCT. [ABSTRACT FROM AUTHOR]