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Transparent Y 2 O 3 –Al 2 O 3 –SiO 2 (YAS) glass-ceramics were prepared by the melting-quenching method and two-step heat treatment. P 2 O 5 is one of the most widely used oxide nucleating agents in the production of glass-ceramics, which can control the crystallization temperature or the grain size. The effects of different amounts of P 2 O 5 on the nucleation, crystallization, structure, and mechanical properties of YAS glasses were studied. Raman spectra fitting showed that with increasing P 2 O 5 content from 0.50 wt% to 4.00 wt%, the content of structure units Q3 and Q4 gradually increased, indicating that P 2 O 5 mainly acted as a network former in YAS glass to enhance the connectivity of silicate glass structure. The results revealed that the increase in P 2 O 5 content led to fewer nucleation sites and lower crystallinity. As the P 2 O 5 content increased, the transmittance of YAS glass-ceramics changed slightly under the same heat treatment, but the Vickers hardness decreased significantly. Fine, granular and evenly distributed nanocrystals were precipitated from YAS precursor glasses through heat treatment at 700 °C for 10 h and 750 °C for 1 h. Additionally, the reported Vickers hardness, fracture toughness and transmittance of YAS glass-ceramic containing 0.50 wt% P 2 O 5 were 674.48 Hv, 1.09 MPa m1/2 and 87.59 %, respectively. [ABSTRACT FROM AUTHOR]

Lithium silicate (LS) glass ceramic with excellent mechanical performance has been used in dental restoration but is seldom used in orthopedics due to its limited bioactivity. Given the osteoconductive features of calcium phosphate-based ceramics, optimizing the P 2 O 5 content to adjust the ratio of CaO to P 2 O 5 may improve the bioactivity of glass ceramics. The effect of P 2 O 5 content on the phase formation, mechanical performance, cell proliferation, cell differentiation and mineralization of glass ceramics were investigated in this study. The results indicated that increasing the content of P 2 O 5 increased the formation temperature of LiAlSi 2 O 6 and provided nucleation sites for Li 2 SiO 3 by forming Li 3 PO 4 which, in turn, promoted the transformation from Li 2 SiO 3 to Li 2 Si 2 O 5. The phase morphology transformed from a lamellar shape to a columnar shape, and then formed an interlocking structure in the specific heat treatment. The phase transformation and formation of Li 3 PO 4 improved cell proliferation, cell differentiation, and mineralization of the glass ceramics. In particular, the glass ceramic with 2.58 mol% P 2 O 5 (LS3) and 4.12 mol% P 2 O 5 (LS4) promoted the expression of alkaline phosphatase (ALP) and achieved the strength requirement of bone. In conclusion, the bioactivity of the glass ceramics was enhanced by increasing the P 2 O 5 content, and the bone-like structure on the surface of the glass ceramic with 4.12 mol% P 2 O 5 may make this material suitable for orthopaedic applications. [ABSTRACT FROM AUTHOR]

Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although straw returning to the field (SRTTF) is conducive to promoting sustainable agricultural production and protecting the environment, straw resources are still wasted due to the lack of suitable straw-returning technology in southern China. Based on the statistical yearbook and a large number of studies, different methods were used to calculate the total straw resources and SRTTF potential, and differences in these methods were compared. The results indicate that the total amount of straw resources in southern China in 2021 was 3.35×108 t. The nutrient content of K2O in the straw accounted for the highest proportion of total nutrient resources (63.66%), followed by N (26.88%) and P2O5 (9.46%). In theory, total SRTTF could replace almost all K2O and part of N and P2O5, indicating that the nutrient substitution potential of SRTTF was high. It is suggested that the SRTTF method be adopted in the middle and lower reaches of the Yangtze River, which mainly uses direct returning (DR) supplemented by indirect returning (IDR). In southeast China, straw returning is carried out by the combination of IDR and IR. In southwest China, straw returning is mainly carried out by IR and supplemented by MDR. This study will provide theoretical support for the government to formulate straw-returning policy. [ABSTRACT FROM AUTHOR]

Since the glass is matastable from the viewpoint of thermodynamics, the highlevel liquid waste glass may crystallize during the process of production, storage, and disposal. Borosilicate glass is used as the matrix for immobilization of highlevel liquid waste in China. It is worth noting that pyroxene phase is easy to crystallize in borosilicate waste glass. In order to suppress the crystallization of pyroxene phase, it was proposed that MgO and CaO in the borosilicate glass formula were partially replaced by P2O5 in this study. The effect of P2O5 content (mass fraction of 08%) on the crystallization characteristics and leaching resistance of borosilicate waste glass was mainly investigated. The results show that the waste glass possesses amorphous phase when the content of P2O5 is 03%. For the samples after heating at 850 ℃ for 6 h, the main crystalline phases are pyroxene when P2O5 content is 02%. In addition, a small amount of calcium silicate phase appears for the heat treated samples with 3% P2O5 content, and pyroxene phase almost disappears. When the content of P2O5 is higher than 3%, spherical Na3Ca6(PO4)5 crystals precipitate in the glass, and the crystallinity increases with P2O5 content. The analyses of 29Si and 11B MAS NMR show that with the increase of P2O5 content from 0 to 6%, the total content of Q3 and Q4 structural units in the glass network gradually increase from 5304% to 8356%, and the content of BO3 structural units increases from 2943% to 3822%. The increase of P2O5 content improves the densification of the overall network structure of the waste glass. The results of the static leaching method (MCC1) show that the normalized leaching rates LRSi, LRB, LRNa and LRCs of the waste glasses gradually decrease with the increase of P2O5 content. After 28 d, LRSi, LRB, LRNa and LRCs of the waste glass with 3% P2O5 content are 0508, 0468, 0533 and 0280 g/(m2·d), respectively, which can satisfy the requirements (

Biodiesel production via catalytic transesterification of non-edible oils derived from plants is one of the priority areas considered by researchers as an approach to reduce the over-dependence on fossil fuels. However, the development of most appropriate catalyst system is still under investigation. The current study therefore investigated the potentials of bone ashes derived from cow, camel and goat as catalytic materials for upgrading mango seed oils into biodiesel under a range of reaction conditions. Irrespective of the bone ash type, the XRF data revealed the presence of CaO, P2O5, SiO2, Al2O3, K2O, Na2O, MgO, TiO2 and Fe2O3. Among the nine oxides, CaO and P2O5 were found to play a competitive role during the upgrading reaction. However, reactions influenced by active basic sites in CaO were very favourable and accounted for the production of high biodiesel yields reaching maximum at ~94.5%. Further studies on properties characterization showed the produced methyl esters to have properties in line with those approved internationally for the designing of B100 and other grades of biodiesel. [ABSTRACT FROM AUTHOR]

The crystallization behaviours, mechanical and optical properties of fluormica glass-ceramic system without and with P2O5 as nucleating agent are studied. The crystallization mechanism of fluor-phlogopite (KMg 3 (Si 3 AlO 10)F 2) without P 2 O 5 oxide represented one-dimensional surface crystallization with a fixed number of nuclei, and with the addition of P 2 O 5 , the mechanism tends to two-dimensional bulk crystallization with a constant nucleation rate being the most predominant phase, forsterite crystals (Mg 2 SiO 4). The base glasses had the spinodal phase separation, which coarsened considerably by increasing P 2 O 5 content. P 2 O 5 had a strong influence on the microstructure and morphology of this type of glass-ceramic. The addition of small amount of P 2 O 5 (1.0 mol%) to these glass-ceramic changed the microstructure from dendritic growth having leaf-like feature to a flower-like morphology of the crystal phase. Glass-ceramic without P 2 O 5 produces yellowish to colourless transparent glass-ceramic, and with the incorporation of the P 2 O 5 (1.0 mol%), which has been found the optimum to obtain transparent glass-ceramics, the transmittance is still about 85%. As the P 2 O 5 content increased to 3.0 mol%, besides fluor-phlogopite mica, forsterite also precipitates, the size of the crystals increase, their distributions turned to be broad due to the change of the crystallization mechanism and the transparency of glass-ceramic consequently decreases. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The molecular structure and properties of a three-layer system based on CaH2, P2O5, microcrystalline cellulose + miramistin deposited via a low-energy electron beam onto a wound dressing have been considered. A cross-linked cellulose layer containing carbon particles and a drug component serves as the coating. The cross-linked structure of the coating enhances the resistance of the miramistin to thermal degradation. The high sorption activity of the gauze substrate determines the exponential nature of the change in the miramistin concentration in the solution. The deposition of a three-layer coating (CaH2 + P2O5 + (cellulose + miramistin)) allows imparting prolonged antibacterial (E. coli, S. aureus) and antifungal (C. alibicans) properties to gauze dressings, reducing the rate of moisture desorption from its volume as a result of the hydrogel formation on the surface of the fibers. Here, the hydrogel formation affects the decrease (over two times) in the gauze's ability to sorb moisture.

Commercial dental lithium disilicate based glass-ceramics containing various amounts of P2O5 were synthesized. Regarding the crystallization behavior and physico-chemical properties of the glasses, the optimum percent of P2O5 was determined.as 8 %wt. Crystallization behavior of the glasses was investigated by X-ray diffraction (XRD) and differential thermal analysis (DTA). The micro-hardness and chemical resistance of both glass and glass-ceramic searies were also determined. According to our results, lithium phosphate was precipitated prior to crystallization of the main phases, i.e lithium meta silicate and lithium disilicate. This early precipitation led to evacuation of residual glass phase from lithium ions, which caused increasing the viscosity of glass and so shifting of crystallization to higher temperatures. In addition, increasing in P2O5 amounts and consequently increasing in Li3PO4, led to significant decrease in the crystallite size and aspect ratio of crystals. Furthermore, while the chemical resistance of the glasses was decreased with P2O5, it was increased with P2O5 after heat treatment process. The chemical solubility of these three glass-ceramics was between 2080~1188 μg/cm2.

Copyright of Revista de Ciências Agrárias is the property of Sociedade de Ciencias Agrarias de Portugal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Keywords: Carl Sprengel; fertiliser; Jöns Jakob Berzelius; Justus von Liebig; P2O5; phosphorus; Sprengel-Liebig's law of the minimum; superphosphate EN Carl Sprengel fertiliser Jöns Jakob Berzelius Justus von Liebig P2O5 phosphorus Sprengel-Liebig's law of the minimum superphosphate 1901 1903 3 11/05/21 20211201 NES 211201 I Phosphorus i (P) is very likely the most frequently misspelled nutrient in scientific literature (Lambers & Plaxton, 2015). He was shocked by the vast amount of P, until his Chinese friend and translator pointed to the fertiliser bag, and he realised the amount had to be divided by 2.29 to know how much P that really was. Other forms of P fertiliser include potassium phosphate, monoammonium phosphate and diammonium phosphate (Syers I et al i ., 2008; Johnston & Poulton, 2019). [Extracted from the article]

Os frutos da bananeira ‘FHIA 18’ possuem características sensoriais semelhantes à banana ‘Prata’, porém, não existem informações sobre as reais necessidades em fósforo (P) deste híbrido e seus efeitos na produção e qualidade pós-colheita. O objetivo deste trabalho foi avaliar o perfil físico-químico dos frutos da bananeira ‘FHIA 18’ submetida à níveis de adubação fosfatada, em São Manuel-SP, durante três ciclos sucessivos. Os níveis de adubação com P2O5 aplicados foram: sem adubação com P (0%); 20 kg ha-1 ano-1 (50%); 30 kg ha-1 ano-1 (75%); 40 kg ha-1 ano-1 (100%); 50 kg ha-1 ano-1 (125%); e 60 kg ha-1 ano-1 (150%). Utilizou-se o delineamento inteiramente casualizado, em arranjo de parcelas subdivididas, sendo as parcelas compostas pelos seis níveis de adubação com fósforo e as subparcelas pelos três ciclos de produção (2014, 2015 e 2016). Foram avaliados nos frutos verdes os teores de matéria seca, amido, açúcares totais, açúcares redutores e de fósforo. Nos frutos maduros avaliou-se a firmeza, os descritores de coloração da casca, acidez titulável total, sólidos solúveis totais, índice de maturação, açúcares totais e açúcares redutores. A adubação fosfatada proporcionou aumento nos teores de fósforo nos frutos verdes até a aplicação de 100% da recomendação e aumento dos teores de açúcares redutores até a aplicação de 61% no primeiro ciclo de produção. Quanto aos frutos maduros, a utilização de fósforo em doses inferiores às recomendadas (100%) promoveu menor acidez titulável total e maior índice de maturação (52-53% da recomendação). Por outro lado, independente da dose de P2O5 utilizada, os teores de matéria seca, amido e fósforo, nos frutos verdes, e a firmeza, teores de sólidos solúveis totais, índice de maturação e teores de açúcares nos frutos maduros, aumentam do primeiro ao terceiro ciclo de produção.

This study investigated arbuscular mycorrhizal fungi (AMF) inoculation and phosphorus fertilizer on growth, productivity and quality of onion grown under saline soil conditions. The experiment was conducted in the Experimental Farm of Desert Research Center, Ras Sudr, South Sinai Governorate, Egypt. Egyptian local onion cultivar “Giza 20” was selected. Treatments were: two arbuscular mycorrhizal fungi (AMF) inoculation treatments [without inoculation (–AMF) and with mycorrhizal inoculation (+AMF)] and four phosphorus supplied treatments (0, 48, 96 and 144 kg P2O5 ha–1). Mycorrhizal inoculation and phosphorus addition affected the plant growth, bulb yield and quality. Morphological traits of plant (height, leaf number, fresh and dry weight), neck diameter, bulb characters (diameter and weight), total soluble sugars (TSS), protein, P content increased, while proline content decreased due to the inoculation of AMF and phosphorus application. Onion inoculated by AMF combined with 96 or 144 kg P2O5 ha–1 gave the highest productivity under saline conditions.

The original AOD slag in the cold state contained more than 50 wt% low-hydration activity γ-C 2 S, which significantly affects the hydration activity. Therefore, the effect of the typical crystal stabilizer P 2 O 5 on the formation of a new phase and the enhancement in the mass fraction of high hydration activity β-C 2 S in AOD slag were studied, and the internal factors that controlled the doping preference and influenced the hydration activity of the crystal stabilizer P 2 O 5 were revealed. When the addition of P 2 O 5 was 0.6 wt%, the mass fraction of β-C 2 S in AOD slag was increased by 50.8 wt%. The P5+ and its oxide P 2 O 5 entered the lattice of C 2 S in solid solution, causing lattice distortion. After P doping, the charge energies of the Ca, Si and O atoms shifted toward the low energy direction by approximately 5 eV, which increased the stability of the electronic structure. In addition, P doping changed the delocalization of the CBM in the pure phase, partially located the LDOS of the VBM and CBM, and increased the numbers of nucleophilic and electrophilic attack sites, thus improving the hydration activity of β-C 2 S. [Display omitted] • The formation rule of the new phase and the enhancement effect of the β-C 2 S content are investigated. • When the addition of P 2 O 5 was 0.6 wt%, β-C 2 S reached the maximum content, increased by50.8 wt%. • P5+ and its oxide P 2 O 5 can be enriched at the initiation of cracking and accelerate the particle cracking behavior. • P doping increases the number of nucleophilic and electrophilic attack sites by changing the delocalization of the CBM. [ABSTRACT FROM AUTHOR]

This study investigated arbuscular mycorrhizal fungi (AMF) inoculation and phosphorus fertilizer on growth, productivity and quality of onion grown under saline soil conditions. The experiment was conducted in the Experimental Farm of Desert Research Center, Ras Sudr, South Sinai Governorate, Egypt. Egyptian local onion cultivar 'Giza 20' was selected. Treatments were: two arbuscular mycorrhizal fungi (AMF) inoculation treatments [without inoculation (-AMF) and with mycorrhizal inoculation (+AMF)] and four phosphorus supplied treatments (0, 48, 96 and 144 kg P2O5 ha-1). Mycorrhizal inoculation and phosphorus addition affected the plant growth, bulb yield and quality. Morphological traits of plant (height, leaf number, fresh and dry weight), neck diameter, bulb characters (diameter and weight), total soluble sugars (TSS), protein, P content increased, while proline content decreased due to the inoculation of AMF and phosphorus application. Onion inoculated by AMF combined with 96 or 144 kg P2O5 ha-1 gave the highest productivity under saline conditions. [ABSTRACT FROM AUTHOR]

Inventing new ways to recycle and reuse the accumulated byproducts is the most pressing and daunting challenge that is facing future engineers. Millions of tons of phosphogypsum (PG) is stacked worldwide every year. Many researchers used a number of physical, chemical and thermal methods to reduce P2O5 content in PG, but all of these studies are univariant. In this study, a multivariant 24 full factorial methodologies is designed to study the effect of particle size, acid concentration, loading and number of washing on the P2O5 washing/leaching process using sulfuric and nitric acid solutions. The Factorial design analysis helped to get more insight on the relative magnitude of the main and the interaction effects. Sulfuric and nitric acid treatment results indicate clearly the importance of the number of washing on the reduction of P2O5 content. This emphasized the importance of renewing the driving force (adding each time a clean solution) washing leaching P2O5 reduction process. It is found that the optimum conditions for sulfuric acid treatment is estimated to be of loading equal to 0.15 g PG/g sol and three washings. The optimum conditions for nitric acid treatment are estimated to be loading of 0.4 g PG/g sol and three washings. [ABSTRACT FROM AUTHOR]

Commercial dental lithium disilicate based glass-ceramics containing various amounts of P2O5 were synthesized. Regarding the crystallization behavior and physico-chemical properties of the glasses, the optimum percent of P2O5 was determined.as 8 %wt. Crystallization behavior of the glasses was investigated by X-ray diffraction (XRD) and differential thermal analysis (DTA). The micro-hardness and chemical resistance of both glass and glass-ceramic searies were also determined. According to our results, lithium phosphate was precipitated prior to crystallization of the main phases, i.e lithium meta silicate and lithium disilicate. This early precipitation led to evacuation of residual glass phase from lithium ions, which caused increasing the viscosity of glass and so shifting of crystallization to higher temperatures. In addition, increasing in P2O5 amounts and consequently increasing in Li3PO4, led to significant decrease in the crystallite size and aspect ratio of crystals. Furthermore, while the chemical resistance of the glasses was decreased with P2O5, it was increased with P2O5 after heat treatment process. The chemical solubility of these three glass-ceramics was between 2080~1188 μg/cm2. [ABSTRACT FROM AUTHOR]

We demonstrated p-type conduction in MoS2 grown with phosphorous pentoxide via chemical vapor deposition (CVD). Monolayer MoS2 with a triangular shape and 15-µm grains was confirmed by atomic force microscopy. The difference between the Raman signals of the A1g and E12g modes for both the pristine and P-doped samples was 19.4 cm−1. In the X-ray photoelectron spectroscopy results, the main core level peaks of P-doped MoS2 downshifted by about 0.5 eV to a lower binding energy compared to the pristine material. Field-effect transistors (FETs) fabricated with the P-doped monolayer MoS2 showed p-type conduction with a field-effect mobility of 0.023 cm2/V⋅s and an on/off current ratio of 103, while FETs with the pristine MoS2 showed n-type behavior with a field-effect mobility of 29.7 cm2/V⋅s and an on/off current ratio of 105. The carriers in the FET channel were identified as holes with a concentration of 1.01 × 1011 cm−2 in P-doped MoS2, while the pristine material had an electron concentration of 6.47 × 1011 cm−2.

A new method has been developed for the synthesis of novel Schiff bases containg anthraquinone moiety using dodeca-Tungstosilicic acid/P2O5 under solvent free conditions at room temperature. The reaction was completed in 1-3 minutes with excellent yields. This method was found to be more efficient, easy and hazardous free for the synthesis of azomethines. The development of these type of methadologies in synthetic chemistry may contribute to green chemistry. The structures of synthesized novel Schiff bases was elucidated using 1H-NMR, 13C-NMR, LCMS, FTIR and CHN analysis.

Chemical strengthening of aluminosilicate glasses through K+-Na+ ion exchange has attracted tremendous attentions because of the accelerating demand for high strength and damage resistance glasses. However, a paramount challenge still exists to fabricate glasses with a higher strength and greater depth of ion-exchange layer. Herein, aluminosilicate glasses with different contents of P2O5 were prepared and the influence of P2O5 on the increased compressive stress and depth of ion-exchange layer was investigated by micro-Raman technique. It was noticed that the hardness, compressive stress, as well as the depth of ion-exchange layer substantially increased with an increasing concentration of P2O5 varied from 1 to 7 mol%. The obtained micro-Raman spectra confirmed the formation of relatively depolymerized silicate anions that accelerated the ion exchange. Phosphorus containing aluminosilicate glasses with a lower polymerization degree exhibited a higher strength and deeper depth of ion-exchange layer, which suggests that the phosphorus containing aluminosilicate glasses have promising applications in flat panel displays, windshields, and wafer sealing substrates.

To study the effect of B2O3 and P2O5 on fluorosilicic mica glass-ceramic sintering process, six sets of K2O-MgO-SiO2-F glasses were prepared by using B2O3 and P2O5 as sintering aid, respectively. Green bodies of the glass powder were formed by gel casting and sintered at 800, 850, 900, 950, 1000oC for 6 hours, resectively. The sintering and crystallization behavior were studied by thermal shrinkage , X-ray diffraction and SEM. The results showed that the shrinkage rate of the glass with 2wt% B2O3 and P2O5 was highest, while the rate of the glass with 5wt% P2O5 was lowest. An additional crystal other than fluorosilicic mica was precipitated in the glass ceramics generated by sintering of glass powder. The present results confirmed that the glass powder of pure K2O-MgO-SiO2-Fsystem had poor sinterability, while glass powder with minor addition of P2O5 and/or B2O3 showed good sinterability. This result was also verified by SEM.

In the current study, the effect of P2O5on the mechanical properties of porous natural hydroxyapatite (NHA) derived from cortical bovine bones sintered at 1,050°C is assessed. Hydroxyapatite (HA: Ca10(PO4)6(OH)2) was synthesized using several methods and manufactured from natural materials such as coral or bone after removal of the organic matter by heating (noted NHA). Thein vitro and in vivostudies showed that the natural apatite was well tolerated and has better osteoconductive properties than synthetic HA. Consequently, the NHA was manufactured from cortical bovine bone in all our studies. Nevertheless, its poor mechanical properties are one of the most serious obstacles for wider applications. So, P2O5was added into NHA in order to enhance its initially poor mechanical strength. A careful combination between the main parameters controlling NHA elaboration such as milling techniques, compacting pressure, sintering temperature, and holding time may lead to an interesting NHA-based bioceramics. In this way, a vibratory multidirectional milling system using bimodal distribution of highly resistant ceramics has been used for obtaining submicron-sized NHA powders. To enhance the densification and lower the sintering temperature of porous NHA, different percentages of P2O5(0.5–5.0 wt%) were added into NHA powders. The porosity ratio ranged between 36 and 41%. Using this modified milling system, the best Vickers micro-hardness and the three-point bending strength values of powders sintered at 1,050°C were 1 GPa and about 46 MPa, respectively. The latter value is significantly higher than that reported by other researchers (35 MPa) using the sol–gel method. [ABSTRACT FROM PUBLISHER]

The effect of TiO 2 and P 2O 5 on the ferric/ferrous ratio in silicate melts was investigated in model silicate melts at air conditions in the temperature range 1,400–1,550 °C at 1-atm total pressure. The base composition of the anorthite–diopside eutectic composition was modified with 10 wt % Fe 2O 3 and variable amounts of TiO 2 (up to 30 wt %) or P 2O 5 (up to 20 wt %). Some compositions also contained higher SiO 2 concentrations to compare the role of SiO 2, TiO 2, and P 2O 5 on the Fe 3+/Fe 2+ ratio. The ferric/ferrous ratio in experimental glasses was analyzed using a wet chemical technique with colorimetric detection of ferrous iron. It is shown that at constant temperature, an increase in SiO 2, TiO 2, and P 2O 5 content results in a decrease in the ferric/ferrous ratio. The effects of TiO 2 and SiO 2 on the Fe 3+/Fe 2+ ratio was found to be almost identical. In contrast, adding P 2O 5 was found to decrease ferric/ferrous ratio much more effectively than adding silica. The results were compared with the predictions from the published empirical equations forecasting Fe 3+/Fe 2+ ratio. It was demonstrated that the effects of TiO 2 are minor but that the effects of P 2O 5 should be included in models to better describe ferric/ferrous ratio in phosphorus-bearing silicate melts. Based on our observations, the determination of the prevailing fO 2 in magmas from the Fe 3+/Fe 2+ ratio in natural glasses using empirical equations published so far is discussed critically. [ABSTRACT FROM AUTHOR]

A highly efficient procedure for the synthesis of triarylmethane and diarylmethane via benzylation of aromatic hydrocarbons from benzyl alcohols using supported P2O5 on SiO2 and/or Al2O3 under solvent-free conditions is described. Excellent yields of triarylmethane and diarylmethane were obtained using P2O5-SiO2 (50%W/W) and/or P2O5-Al2O3 (50%W/W) at room temperature. The reusability of both supported P2O5 on SiO2 and Al2O3 were examined. Both supported reagents show favorable activities in first and second runs, however, a decline in reactivity was observed in following attempts. The reaction is scalable to >0.03 mole amounts. [ABSTRACT FROM AUTHOR]

Abstract: Lithium aluminum silicate (LAS) glass of composition (mol%) 20.4Li2O–4.0Al2O3–68.6SiO2–3.0K2O–2.6B2O3–0.5P2O5–0.9TiO2 was prepared by melt quenching. The glass was then nucleated and crystallized based on differential thermal analysis (DTA) data and was characterized by 29Si, 31P, 11B and 27Al MAS-NMR. XRD and 29Si NMR showed that lithium metasilicate (Li2SiO3) is the first phase to c form followed by cristobalite (SiO2) and lithium disilicate (Li2Si2O5). 29Si MAS-NMR revealed a change in the network structure already for the glasses nucleated at 550°C. Since crystalline Li3PO4, as observed by 31P MAS-NMR, forms concurrently with the silicate phases, we conclude that crystalline Li3PO4 does not act as a nucleating agent for lithium silicate phases. Moreover, 31P NMR indicates the formation of M–PO4 (M=B, Al or Ti) complexes. The presence of BO3 and BO4 structural units in all the glass/glass-ceramic samples is revealed through 11B MAS-NMR. B remains in the residual glass and the crystallization of silicate phases causes a reduction in the number of alkali ions available for charge compensation. As a result, the number of trigonally coordinated B (BO3) increases at the expense of tetrahedrally coordinated B (BO4). The 27Al MAS-NMR spectra indicate the presence of tetrahedrally coordinated Al species, which are only slightly perturbed by the crystallization. [Copyright &y& Elsevier]

Abstract: In this study P2O5/Al2O3 is found to catalyze the preparation of Schiff bases from the reaction of carbonyl compounds with primary amines efficiently under solvent-free conditions. The advantages of this friendly, environmentally and mild method are such as simplicity of the reaction procedure, the elimination of solvents, simple work-up, high product yields and short reaction times. [Copyright &y& Elsevier]

We demonstrated p-type conduction in MoS2 grown with phosphorous pentoxide via chemical vapor deposition (CVD). Monolayer MoS2 with a triangular shape and 15-µm grains was confirmed by atomic force microscopy. The difference between the Raman signals of the A1g and E12g modes for both the pristine and P-doped samples was 19.4 cm−1. In the X-ray photoelectron spectroscopy results, the main core level peaks of P-doped MoS2 downshifted by about 0.5 eV to a lower binding energy compared to the pristine material. Field-effect transistors (FETs) fabricated with the P-doped monolayer MoS2 showed p-type conduction with a field-effect mobility of 0.023 cm2/V⋅s and an on/off current ratio of 103, while FETs with the pristine MoS2 showed n-type behavior with a field-effect mobility of 29.7 cm2/V⋅s and an on/off current ratio of 105. The carriers in the FET channel were identified as holes with a concentration of 1.01 × 1011 cm−2 in P-doped MoS2, while the pristine material had an electron concentration of 6.47 × 1011 cm−2. [ABSTRACT FROM AUTHOR]