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Synthesis and luminescence properties of novel Sr6YAl(BO3)6 borate belonging to STACK (STACK is an acronym derived from the first letters of the surnames of the inventors; Schaffers, Thompson, Alekel, Cox, Keszler) family was reported for the first time. XRD measurement and Rietveld refinement were performed to check the phase purity of the prepared samples. Photoluminescence emission (PL) and excitation (PLE) spectra were measured for Tb3+ and Gd3+ doped Sr6YAl(BO3)6. The observed emission and excitation spectra show characteristic peaks of Tb3+ and Gd3+. The PLE and PL spectra of Gd3+ arise due to f-f transitions, whereas in the case of Tb3+, the excitation band is ascribed to the f-d transition and emission comes from the f-f transitions. Trivalent activators Tb3+ and Gd3+ occupy Yttrium sites. Owing to fixed, well-separated positions (Y-Y distance 7.67 Å), a large concentration of activators could be activated. As much as 10 mol% activators could be accommodated without causing concentration quenching. Luminescence decay measurements were also performed which shows the lifetime of the order of milliseconds, typical of forbidden f-f transitions, for both Gd3+ and Tb3+ ions. Low concentration quenching makes Sr6YAl(BO3)6borate host attractive for various phosphor applications. [ABSTRACT FROM AUTHOR]

Synthesis and luminescence properties of novel Sr6YAl(BO3)6 borate belonging to STACK (STACK is an acronym derived from the first letters of the surnames of the inventors; Schaffers, Thompson, Alekel, Cox, Keszler) family was reported for the first time. XRD measurement and Rietveld refinement were performed to check the phase purity of the prepared samples. Photoluminescence emission (PL) and excitation (PLE) spectra were measured for Tb3+ and Gd3+ doped Sr6YAl(BO3)6. The observed emission and excitation spectra show characteristic peaks of Tb3+ and Gd3+. The PLE and PL spectra of Gd3+ arise due to f-f transitions, whereas in the case of Tb3+, the excitation band is ascribed to the f-d transition and emission comes from the f-f transitions. Trivalent activators Tb3+ and Gd3+ occupy Yttrium sites. Owing to fixed, well-separated positions (Y-Y distance 7.67 Å), a large concentration of activators could be activated. As much as 10 mol% activators could be accommodated without causing concentration quenching. Luminescence decay measurements were also performed which shows the lifetime of the order of milliseconds, typical of forbidden f-f transitions, for both Gd3+ and Tb3+ ions. Low concentration quenching makes Sr6YAl(BO3)6borate host attractive for various phosphor applications. [ABSTRACT FROM AUTHOR]

Boron is an essential mineral for plants, and as such, is a normal dietary constituent for humans. Humans may be naturally exposed to boron through food and drinking water, or via anthropogenic sources such as consumer products. The World Health Organisation established an acceptable safe range of population mean intakes for boron of 1–13 mg/day. Most studies of dietary boron intake show a range of 1–2 mg/day. Consumer products have been estimated to contribute a geometric mean daily intake of 0.1 mg to total boron exposure; however, there are few published surveys of consumer exposure to boron from use of cleaning products. The Government of Canada published a draft screening assessment report of boric acid, its salts and precursors that included estimates of consumer exposure to boron found as ingredients in consumer products. The manufacturers of consumer cleaning products conducted a survey of boron content of current products and estimated exposure using the publicly available exposure tool ConsExpo Web. Dermal exposures to boron during cleaning product use were estimated to result in annual internal exposures ranging from ≪0.001 to 0.36 μg/kg bw/day based on dermal absorption of 0.5%. Using a conservative point of departure for hazard assessment (2,900 μg boron/kg bw/day), estimated margins of exposure for dermal exposures to boron from cleaning product use range from 8,056 to >1,000,000. This work demonstrates that exposure to boron from cleaning product use is very low and essentially insignificant when compared to other (e.g. dietary) sources of boron intake by Canadian consumers. [ABSTRACT FROM AUTHOR]

Vinyl phosphorus compounds such as poly (vinyl phosphonic acid) (PVPA), poly (dimethyl vinyl phosphonate) (PDMVP) impart high flame retardancy to wood comparable to conventional fireproofing wood by combined use of sodium polyborate (SPB) in contrast to their single use. The differential thermal analysis and thermogravimetry (DTA/TG) suggest a synergy effect between SPB and PVPA. The water resistance of the treated wood is improved by copolymerization of dimethyl vinyl phosphonate (DMVP) with methyl methacrylate (MMA) inside the wood after the impregnation of SPB, and the incombustibility of the wood is mostly maintained after leaching tests. The combustion residues of the wood treated with DMVP and MMA after SPB show high compressive strength, and their SEM images suggest that the strength is due to formed charcoal. [ABSTRACT FROM AUTHOR]

Wood is by far the best structural material in terms of environmental impact. This superiority can be improved if the longevity of the commodity is extended by reducing the decay susceptibility of the heartwood not typically treatable using pressure methods. Traditionally, heartwood decay has been managed by remedial treatments, or simply by accepting the short service life and the required product replacement costs. Dual treatment is defined here as combining two (dual) preservative systems, a water-diffusible system and an oil-borne pressure-impregnated system being applied to the same piece of wood. This is often done as separate treatments; in this case, it is essentially the same as using an oil-borne preservative with a remedial diffusible treatment (typically a sodium borate salt), but has the benefit of preventing decay before it happens. Adding borates to railroad crossties prior to seasoning and treatment has been shown to provide significant benefit to crossties and utility poles. Treatment of bridge timbers has now also been commercialized using a further modification of this approach, with even higher unit cost savings and commercial testing is now underway in utility poles. The global infrastructure industry is urged to review the opportunity offered with this now-proven technology. [ABSTRACT FROM AUTHOR]

Copolymerization of ethylene (E) and propylene (P) and their terpolymerizations with three kinds of diene (5-ethylidene-2-norbornene (ENB), 4-vinylcyclohexene (VCH) and 1,4-hexadiene (HD)) under 4 bar monomer pressure in n-heptane solution were studied. Two ansa-zirconocenes (rac-Me2Si(2-Me-4-Ph-Ind)2ZrCl2 (Mt-I) and rac-Et(Ind)2ZrCl2 (Mt-II)) activated by (Ph3C)B(C6F5)4/triisobutylaluminum were used as the catalyst, respectively. In general, addition of diene depressed the polymerization activity. ENB exerted the strongest deactivation effect on Mt-I, and HD caused the strongest deactivation on Mt-II. Among the two metallocenes, activity of Mt-I was more sensitive to the diene. Increasing diene concentration in the monomer feed caused lower propylene incorporation rate and shorter average length of polypropylene sequences, and the average length of polyethylene sequences was increased by adding more HD in E/P/HD terpolymerization with Mt-II. The Mt-II/borate catalyst showed high activity and diene incorporation rate for E/P/ENB terpolymerization. In contrast, Mt-I/borate catalyst showed high activity and propylene incorporation rate for E/P copolymerization, but was nearly inactive for E/P/ENB terpolymerization. [ABSTRACT FROM AUTHOR]

Creosote-treated wooden bridge ties in the South-Eastern U.S.A. last about 15-20 years, which falls well below the national average of 40 years for crossties. It was demonstrated that diffusion of inserted liquid disodium octaborate tetrahydrate within wooden bridge ties was dramatically increased during Boulton treatment. The objective of this study was to determine how much diffusion of borate inside the bridge tie occurred over time, after initial treatment. Green hardwood bridge ties were ported, borate treated and then Boulton treated with copper naphthenate at a commercial tie treatment plant. Retention and location of borate within the wood was tested at 3, 14 and 40 weeks after the treatment. As previously found, movement of borate within the wood was significantly enhanced by the elevated temperature and steam generated during the Boulton cycle. It appeared that borate continued to diffuse inside of the tie and would likely treat and protect a significant volume of the heartwood over time and thus increase bridge tie life in a similar way to crossties. It is hoped that the results will reduce environmental impact, improve safety and enable railroads to continue to use wood with confidence. [ABSTRACT FROM AUTHOR]

Material processing adopting microwave heating has emerged as an alternative tool owing to faster processing, a cleaner environment, and several other advantages. This review provides a summary of recent reports of microwave synthesis of materials. This study reviews the use of microwave energy for application in several material processing technologies apart from food processing. A special emphasis has been made in the processing of glass adopting microwave energy. Melting of glass comprising SiO2, P2O5, B2O3as the main building block has been discussed. It has been revealed that silica, a microwave transparent material as reported earlier, can be heated under microwave heating directly. Microwave absorption of raw materials and different glass system has been discussed. Dielectric properties, particularly loss tangent or loss factor, are presented for some glass composition. Less evaporation of ingredient and low contamination from the crucible wall are noticed during glass melting using microwave heating. Enhanced iron redox ratio (Fe+2/∑Fe) in microwave processing may be considered an advantage in the preparation of heat absorbing filter glass. Small-scale glass melting using the microwave heating has a significant impact on energy and time saving. However, the challenges associated with the upscaling glass melting with microwave heating and future scope have been talked about. [ABSTRACT FROM AUTHOR]

Different xPbO–(1–x)B2O3glasses were prepared by conventional melting method. They were investigated by differential scanning calorimetry (DSC), Raman and IR spectroscopy. The glasse's structure and the PbO role to the formation of the borate units in the framework is investigated. The dielectric constant and dielectric loss were measured at different frequencies and as a function of the temperature. The electrical measurements carried out showed semiconductor behavior of the conductivity as a function of temperature. The activation energies (Ea) for the conduction process indicated a thermally activated hopping mechanism. The calculated Ea values are typically 0.67–2.46 eV. [ABSTRACT FROM AUTHOR]

We have studied the mineral kaliborite. The sample originated from the Inder B deposit, Atyrau Province, Kazakhstan, and is part of the collection of the Geology Department of the Federal University of Ouro Preto, Minas Gerais, Brazil. The mineral is characterized by a single intense Raman band at 756 cm−1assigned to the symmetric stretching modes of trigonal boron. Raman bands at 1229 and 1309 cm−1are assigned to hydroxyl in-plane bending modes of boron hydroxyl units. Raman bands are resolved at 2929, 3041, 3133, 3172, 3202, 3245, 3336, 3398, and 3517 cm−1. These Raman bands are assigned to water stretching vibrations. A very intense sharp Raman band at 3597 cm−1with a shoulder band at 3590 cm−1is assigned to the stretching vibration of the hydroxyl units. The Raman data are complimented with infrared data and compared with the spectrum of kaliborite downloaded from the Arizona State University database. Differences are noted between the spectrum obtained in this work and that from the Arizona State University database. This research shows that minerals stored in a museum mineral collection age with time. Vibrational spectroscopy enhances our knowledge of the molecular structure of kaliborite. [ABSTRACT FROM AUTHOR]

We have studied the mineral kornerupine, a borosilicate mineral, by using a combination of scanning electron microscopy with energy-dispersive analysis and Raman and infrared spectroscopy. Qualitative chemical analysis of kornerupine shows a magnesium–aluminum silicate. Strong Raman bands at 925, 995, and 1051 cm−1with bands of lesser intensity at 1035 and 1084 cm−1are assigned to the silicon–oxygen stretching vibrations of the siloxane units. Raman bands at 923 and 947 cm−1are attributed to the symmetrical stretching vibrations of trigonal boron. Infrared spectra show greater complexity and the infrared bands are more difficult to assign. Two intense Raman bands at 3547 and 3612 cm−1are assigned to the stretching vibrations of hydroxyl units. The infrared bands are observed at 3544 and 3610 cm−1. Water is also identified in the spectra of kornerupine. [ABSTRACT FROM PUBLISHER]

Priceite is a calcium borate mineral and occurs as white crystals in the monoclinic pyramidal crystal system. We have used a combination of Raman spectroscopy with complimentary infrared spectroscopy and scanning electron microscopy with Energy-dispersive X-ray Spectroscopy (EDS) to study the mineral priceite. Chemical analysis shows a pure phase consisting of B and Ca only. Raman bands at 956, 974, 991, and 1019 cm−1are assigned to the BO stretching vibration of the B10O19units. Raman bands at 1071, 1100, 1127, 1169, and 1211 cm−1are attributed to the BOH in-plane bending modes. The intense infrared band at 805 cm−1is assigned to the trigonal borate stretching modes. The Raman band at 674 cm−1together with bands at 689, 697, 736, and 602 cm−1are assigned to the trigonal and tetrahedral borate bending modes. Raman spectroscopy in the hydroxyl stretching region shows a series of bands with intense Raman band at 3555 cm−1with a distinct shoulder at 3568 cm−1. Other bands in this spectral region are found at 3221, 3385, 3404, 3496, and 3510 cm−1. All of these bands are assigned to water stretching vibrations. The observation of multiple bands supports the concept of water being in different molecular environments in the structure of priceite. The molecular structure of a natural priceite has been assessed using vibrational spectroscopy. [ABSTRACT FROM AUTHOR]

This article reports on the optical properties of Sm3+-activated GdB3O6phosphors based on the measurement of their photoluminescence spectra and luminescence decay curves. Energy transfer from Gd3+to Sm3+and the concentration quenching of the Sm3+ion emission are investigated. From the photoluminescence spectra and decay curves, the energy transfer from Gd3+to Sm3+is confirmed. The concentration quenching of the Sm3+ion emission can be ascribed to resonant cross-relaxation. The interaction between the Sm3+ions is derived of the electric dipole–dipole type through fitting the data with the Inokuti-Hirayama model. The critical distances and energy transfer microparameter for the transfer processes are given. The decay curves of Sm3+4G5/2level exhibiting a buildup and decay process also confirm the energy transfer from Gd3+to Sm3+and between Sm3+ions. [ABSTRACT FROM PUBLISHER]

Subsolidus phase relations in the ternary system TiO2-BaO-B2O3 were analysed with X-ray diffraction. According to the constructed phase relations, 15 ternary phase regions were identified in the subsolid phase, in which 11 binary compounds and 2 ternary compounds were investigated in detail. Additionally, the crystallisation region of rutile was identified, and it was found that rutile crystal with dimension of 10×4×2 mm was grown through spontaneous nucleation from a new flux BaO-B2O3. [ABSTRACT FROM AUTHOR]

Subsolidus phase relations in the ternary system TiO2-BaO-B2O3 were analysed with X-ray diffraction. According to the constructed phase relations, 15 ternary phase regions were identified in the subsolid phase, in which 11 binary compounds and 2 ternary compounds were investigated in detail. Additionally, the crystallisation region of rutile was identified, and it was found that rutile crystal with dimension of 10×4×2 mm was grown through spontaneous nucleation from a new flux BaO-B2O3. [ABSTRACT FROM AUTHOR]

Subsolidus phase relations in the ternary system TiO2-BaO-B2O3 were analysed with X-ray diffraction. According to the constructed phase relations, 15 ternary phase regions were identified in the subsolid phase, in which 11 binary compounds and 2 ternary compounds were investigated in detail. Additionally, the crystallisation region of rutile was identified, and it was found that rutile crystal with dimension of 10×4×2 mm was grown through spontaneous nucleation from a new flux BaO-B2O3. [ABSTRACT FROM AUTHOR]

There are a large number of boron-containing minerals, of which vonseniteis one. Some discussion about the molecular structure of vonsenite exists in the literature. Whether water is involved in the structure is ill-determined. The molecular structure of vonsenite has been assessed by the combination of Raman and infrared spectroscopy. The Raman spectrum is characterized by two intense broad bands at 997 and 1059 cm−1assigned to the BO stretching vibrational mode. A series of Raman bands in the 1200–1500 cm−1spectral range are attributed to BO antisymmetric stretching modes and in-plane bending modes. The infrared spectrum shows complexity in this spectral range. No Raman spectrum of water in the OH stretching region could be obtained. The infrared spectrum shows a series of overlapping bands with bands identified at 3037, 3245, 3443, 3556, and 3614 cm−1. It is important to understand the structure of vonsenite in order to form nanomaterials based on its structure. Vibrational spectroscopy enables a better understanding of the structure of vonsenite. [ABSTRACT FROM AUTHOR]

Four organotin(IV) complexes of dihydrobis(2-mercaptothiazolinyl)borate were synthesized and characterized by elemental analysis and spectroscopic techniques (IR, 1H-NMR, 13C-NMR, 11B-NMR, and 119Sn-NMR). All the compounds were screened against bacterial, fungal, and cyanobacterial strains. Among the complexes, triorganotin(IV) complexes show better inhibition growth as compared to diorganotin(IV) complexes. [ABSTRACT FROM AUTHOR]

A highly concentrated aqueous solution of sodium polyborate (SPB) was used to treat laminated Japan cedar (Cryptomeria japonica) in order to first develop a fire resistant laminated wood. After the pressure-impregnation of a water borne solution containing 9.78 mol/L of boron, the fire properties were evaluated by cone calorimeter (CCM) and weight loss (WL). The resorcinol formaldehyde resin (RF) laminated wood did not fracture and the adhesive interfaces kept the pieces together even after heating at 750°C for 20 min or with the CCM test using the heat flux of 50 kW/m2 for 20 min. Heat emission for 20 min in the CCM test below 8 MJ/m2 was achieved by a WPG of 53% or more. [ABSTRACT FROM AUTHOR]

The 11B nuclear magnetic resonance (NMR) shielding and electric field gradient parameters for several borate crystal structures have been calculated using density functional theory and the gauge-including projector augmented wave method with plane-wave basis sets and pseudopotential approximation. The results show good agreement with the existing experimental data. Significantly large variation in the 11B NMR isotropic chemical shift is observed for BO3 sites with all three bridging oxygen atoms in triborate and boroxol rings and non-ring geometries. Such variations could be attributed to the corresponding differences in the B-O-B angles. The nature of the boroxol rings in glassy B2O3 is discussed in light of these data. [ABSTRACT FROM AUTHOR]

Potassium hydrotris(2-mercaptobenzathiazolyl)borate (KL) was formed by the solid state reaction of potassium borohydride and 2-mercaptobenzathiazoline. This ligand was reacted with RnSnCl4-n (R = methyl, butyl and phenyl, n = 2 and 3) in dichloromethane and four different neutral organotin(IV) complexes were obtained. All compounds were characterized by elemental analyses, FT-IR and multinuclear NMR (1H, 13C, 11 B and 119Sn) spectroscopy. Spectroscopic data indicate the six-coordinated nature of tin in its di and triorganotin(IV) complexes. To check the toxic potential of the ligand and its organotin(IV) complexes, selected bacterial (E. coli, S. epidemidis and S. dysenteriae) and fungal (A. niger, C. albicanes and A. flaves) species were screened. The results were compared with standard drugs kinamycine and miconazole for bacterial and fungal activity, respectively. The toxicity of the organotin(IV) complexes depends on the number and nature of organic groups attached to the tin atom; triorganotin(IV) complexes exhibit better inhibition than diorganotin(IV) complexes. All compounds were also screened on the cyanobacterial strains (Aulosira fertillissma, Anabaena variabilis, Anabaena species and Nostoc muscorum). Results show that the compounds inhibit the growth of organisms at very low concentration. [ABSTRACT FROM AUTHOR]

An oxo-homoscorpionate ligand [potassium bis(phthalato)borate] (KL) was prepared by solid state reaction of potassium borohydride and phthalic acid (1 : 3 molar ratio). The ligand is uninegative and can be a bi, tri and tetra-dentate chelating agent. The di- and tri-organotin(IV) complexes of this ligand are formed by replacement of chloride in R2SnCl2 and [image omitted] (R = methyl, butyl and R' = phenyl and butyl). The ligand and all its complexes were characterized by elemental analyses and spectral studies (IR, 1H, 13C, 119Sn NMR and ESI mass spectra). Spectroscopic data reveal that all the complexes are hexacoordinate; the diorganotin complexes have trans octahedral geometry while the triorganotin complexes are distorted octahedral geometry. The toxicity of these organotin(IV) derivatives on selected microbes was considered. The compounds exhibit antibacterial (Bacillus anthracius and Escherichia coli) and antifungal (Candida albicans and Penicillium italicum) activities in vitro. The ligand shows less toxicity towards the microorganisms and its toxicity significantly increased after complexation with organotin(IV). Triorganotin derivatives (R3SnL) of the ligand are more effective compared to diorganotin derivatives (R2SnL2). [ABSTRACT FROM AUTHOR]

Boron stripping was carried out with various alkaline solutions. A KOH solution was selected as the stripping phase for a continuous operation since the crystal obtained by KOH solution showed the most boron content. A continuous extraction and stripping operation was conducted by using two mixer-settlers. A long-term continuous operation with a dilute boron solution was carried out steadily for over 500 hours. Over 0.15 m 3 of wastewater was successfully treated, and boron was concentrated to 18 kg/m 3 . A continuous recovery of boron as a crystal was successfully performed at a high boron concentration, 0.32 kg/m 3 . The crystallization of boron took place at its supersaturated concentration (33 kg/m 3 ) when a 56.1 kg/m 3 (1 kmol/m 3 ) KOH solution was used as the stripping phase, and the pH of the stripping phase was maintained at 10.5. [ABSTRACT FROM AUTHOR]

Boron extraction with 2-butyl-2-ethyl-1,3-propanediol (BEPD) and 2-ethylhexanol (EHA) in butyl acetate (BA) was carried out at various boron and extractants concentrations. The distribution ratio of boron was constant for all boron concentrations when EHA was used as the extractant, and it increased with EHA concentration. When high concentrations of BEPD were used as the extractant, the distribution ratio of boron was almost the same for all boron concentrations. The distribution ratio of boron increased with BEPD concentrations. An increase in the initial concentration of boron in the aqueous phase severely decreased the boron distribution ratio at low initial concentrations of BEPD in the organic phase. This was caused by the dissolution of BEPD into aqueous solution. The loss of BEPD into the aqueous phase became severe as the concentration of boron in the aqueous phase increased. The loss of EHA was insignificant for all boron concentrations. The distribution ratio of boron was plotted with a function of the equilibrium concentrations of the extractants. The plots showed a linear relation indicating that boron extraction resulted from the same mechanism in all the extraction systems examined in our study. Distribution equations for all the extraction systems were determined. [ABSTRACT FROM AUTHOR]

Sodium perborate, a true peroxo salt, generates peracetic acid on standing in glacial acetic acid; the oxidations of N-methylaniline and N,N-dimethylaniline with fresh solutions of perborate are second order, but the specific oxidation rate of N-methylaniline increases with [perborate]0. Sodium percarbonate, a dry carrier of hydrogen peroxide, does not generate peracetic acid in glacial acetic acid on aging, and the oxidations of the anilines are clean second order. On dissolution, perborate affords hydrogen peroxide and a borate, and the latter assists the oxidation of N-methylaniline but not N,N-dimethylaniline. [ABSTRACT FROM AUTHOR]

There is increasing commercial interest in treating stumps to restrict the spread of root rot [Heterobasidion annosum (Fr.) Bref.] when thinning Swedish coniferous forests during the summer. Both chemical and biological substances are used for this purpose. During the treatment, however, a large proportion of the substance applied is spilled beside the stumps. A field study was conducted on the effects of stump-treatment substances on various ground-vegetation species in a Picea abies (L.) Karst. forest in Sweden. Three different substances commonly used in forestry were studied: urea solution (0.23 kg N m[sup -2]), borate solution (10 g B m[sup -2]) and a fungal preparation of Phlebiopsis gigantea (Fr.) Jül. spores (1 g spores m[sup -2]). The principal objectives were to assess whether any of the substances were harmful to plants and whether plant species differed in their sensitivity. Both borate and urea solution caused severe damage to most ground-vegetation species tested. Bryophytes were affected more strongly than vascular plants and urea was slightly more toxic than borate. Treatments with P. gigantea caused no obvious damage. The size and persistence of chemical changes in the soil induced by the treatments were also analysed. Transient changes were apparent in topsoil where borate or urea had been added. Very high concentrations of B were initially observed where borate had been applied, and even after 1 yr they were slightly higher than the threshold concentration at which plant injuries are expected. Urea treatment initially resulted in a pH increase of 2 units and a substantial increase in soil ammonium content. After 1 yr these effects had largely disappeared, although some increase in ammonium was still detectable. [ABSTRACT FROM AUTHOR]

An abstract of the article "Radiative Lifetime, Oscillator Strength and Quantum Efficiency Calculations in Nd3+:Ba3La2(BO3)4 Crystal" by Shangke Pan and Guofu Wang is presented.