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In this paper, Er3+ doped TeO 2 -ZnF 2 -BaF 2 -KF-Ta 2 O 5 tellurite glasses with low hydroxyl content (∼0.03 × 10−19 cm−3) were investigated employing both glass composition and glass melting process optimization. The Raman spectra and physical properties were characterized to analyze the structure of the glasses. Under the pumping of 980 nm LD laser, intense up-conversion fluorescence at 1.5 and 2.7 μm of samples and their lifetimes were detected and analyzed, and the related transition mechanisms with gradient-varying Er3+ doping concentrations were discussed. The maximum absorption and emission cross section at 2.7 μm was calculated to be 6.4 × 10−21 cm2 and 6.8 × 10−21 cm2, correspondingly, which were higher than those of traditional tellurite glasses. Using the calculated and measured spectroscopic parameters of bulk tellurite glass, a dual-wavelength pumping model was established to verify the feasibility of mid-infrared laser output in similar tellurite glass fiber. Experimental results support the assertion that the Er3+ doped tellurite glasses hold promise as a candidate laser gain medium for mid-infrared fiber laser systems. [ABSTRACT FROM AUTHOR]

This paper is the editorial for the virtual special issue (VSI) of Renewable and Sustainable Energy Reviews (RSER) dedicated to three Sustainable Development of Energy Water and Environment Systems (SDEWES) Conferences held in 2022, namely: (i) the 5th South East European Conference SEESDEWES 2022 held from May 22 to 26, 2022 in Vlore, Albania; (ii) the 3rd Latin American LASDEWES 2022 held from July 24 to 28, 2022 in Sao Paulo, Brazil and (iii) the 17th SDEWES 2022 held from November 6 to 10, 2022 in Paphos, Cyprus. The VSI collected both high quality review papers and original research articles presented at these conferences, aligning with the aims and scope of RSER. Following a rigorous peer review process, seventeen articles were accepted and published. These articles explore techniques and technologies essential for advancing feasible Renewable and Sustainable Energy Systems. Spanning multidisciplinary topics, many of them address almost all the Sustainable Development Goals, offering feasible solutions for much-needed decarbonization pathways. • The VSI SDEWES 2022 presents the ready solutions for Renewable and Sustainable Energy Systems. • Five clusters for presenting the Renewable and Sustainable energy cutting edge solutions. • The positioning in the scientific context of the Renewable and Sustainable Energy Systems. • Feasible solutions for much-needed decarbonization pathways. [ABSTRACT FROM AUTHOR]

Ever since 2002, when the first Conference on Sustainable Development of Energy, Water and Environment Systems (SDEWES) was held in Dubrovnik, the SDEWES conferences series has been providing a forum for world-wide scientists and those interested in learning about the sustainability of development, to present research progress and to discuss the state of the art, the future directions and priorities in the various areas of sustainable development. One of the main issues of the coming decades is to improve efficiencies by integrating various energy systems, using excess from one, as resource in another in the correct moment. Integrating electricity, heating, cooling, transport, water, buildings, waste, wastewater, industry, forestry and agriculture systems will be pivotal towards sustainable development. SDEWES has maintained high publishing standard as 2408 SDEWES papers were published in special issues of leading scientific journals including "Energy - The International Journal". In 2022, the 17th SDEWES Conference was held during November 6–10 in Paphos, Cyprus, the 5th SEE Conference took place in May 22–26, 2022 in Vlorë, Albania, the 3rd Latin American Conference was held through a virtual platform during July 24–28, 2022. The Energy journal has continued its cooperation with SDEWES launching a special issue dedicated to the 2022 Conferences. The special issue includes papers which traditionally cover a range of energy issues - higher renewables penetration and various technologies and fuels assessments at energy supply side, as well as, energy efficiency in various sectors, buildings, district heating, electric vehicles and demand modelling at energy demand side. [ABSTRACT FROM AUTHOR]

• The effect of protective layer on the performance of smart radiation devices is comprehensively evaluated. • The emission regulation can be enhanced to 0.65, while the solar absorption can be decreased to 0.18. • The performance of the proposed SRD meets the requirement of the spacecraft thermal control devices. • This work provides a theoretical basis for the design of more reasonable spacecraft thermal control devices. With the arrival of the space economy, the miniaturization of spacecraft and their multi-functional trends have put a greater demand on space thermal control systems. Smart radiation devices (SRDs) are gaining attention as a low-cost, light-weight material for the thermal control of spacecraft. Previous works have focused on how to enhance IR emittance tunability of SRDs. In fact, the SRDs performance and lifetime may be affected by the external space environment. Thus, researchers proposed to cover the SRDs with a protective layer to resist oxidation and other problems. However, the influence of protective layer on the performance of SRDs, including IR emittance tunability Δ ε and solar absorption α s , has not been studied systematically yet. In this paper, the impact of protective layer on the performance of SRDs is comprehensively evaluated in theory. Firstly, a three-layer SRD is composed of a vanadium dioxide (VO 2) film, BaF 2 , and a silver (Ag) substrate, which is optimized using the transfer matrix method. The IR emittance tunability and solar absorption can reach 0.64 and 0.29, respectively. Secondly, the smart thermal control device with three protection materials (BaF 2 , Al 2 O 3 and Si) is investigated. The results show that the performance of SRD can be enhanced or deteriorated, depending on the types of protection materials and the thickness. When the protection material is Si, the IR emittance tunability can be enhanced to 0.65, while the solar absorption can be decreased to 0.18. The performance of the proposed SRD meets the requirement of the spacecraft thermal control devices. We believe that this work provides a theoretical basis for the design of more reasonable spacecraft thermal control devices. [ABSTRACT FROM AUTHOR]

Abstract In this paper, BaAl 11 O 16 N (BAON) based oxynitride phosphors have been synthesized via the employment of the flux method and Eu2+/Mn2+ co-doped technique. The effects of different fluxes on phase formation of the phosphor have been investigated. It has been found that BaF 2 is the best flux to prepare BAON as it can decrease the pure phase-forming temperature (∼1550 °C) than the normal solid state synthesis (∼1700 °C). It also gives the best luminescence quantum efficiency. The crystallinity, morphology and grain size of the phosphor can be improved when more BaF 2 flux has been added. The photoluminescence (PL) spectra and decay curves for Eu2+/Mn2+co-doped BAON phosphors reveal that an efficient energy transfer (ET) from Eu2+ to Mn2+ takes place in the BAON host. The corresponding ET efficiencies and mechanisms are evaluated and the critical distance (R c) is calculated in terms of the experimental data and analysis. The emission colors of the co-doped phosphors can be tuned from blue to green by simply varying the doping concentrations of Mn2+. White light-emitting diodes (WLEDs) are fabricated by coating the as-prepared samples on a near ultraviolet (n- UV) LED chip to explore the real application potentials. The excellent performance of this WLEDs verifies that the co-doped phosphor can be used as an efficient green component. Graphical abstract Image 1 Highlights • A simple flux fusion routine for synthesizing BaAl 11 O 16 N:Eu2+,Mn2+ oxynitride phosphors. • Energy transfer between Eu2+ and Mn2+ takes a place in the BaAl 11 O 16 N host. • The WLEDs based on the as-prepared phosphors presents excellent warm white light performance. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we studied the gamma photon attenuation properties for different germanate glasses systems with composition Sb 2 O 3 –GeO 2 –SiO 2 –Al 2 O 3 , TeO 2 –WO 3 –GeO 2 , GeO 2 –TeO 2 /SiO 2 –PbO–CaO–Tm 2 O 3 and B 2 O 3 –GeO 2 –Gd 2 O 3 –Eu 2 O 3 –GdF 3 –BaF 2. The mass attenuation coefficients (μ/ρ) for the selected germanate glasses were calculated at different energies (between 0.015 MeV and 15 MeV) using the MCNPX code. The calculated MCNPX μ/ρ values then compared with the WinXCom data to check the accuracy in the results. The results showed that the Sb 2 O 3 replacement by SiO 2 causes a decrease in μ/ρ for Sb 2 O 3 –GeO 2 –SiO 2 –Al 2 O 3 glass system. Also, it is found that for TeO 2 –WO 3 –GeO 2 glass system, μ/ρ decreases as GeO2 content increases from 1 to 20 mol%. While for GeO 2 –TeO 2 /SiO 2 –PbO–CaO–Tm 2 O 3 glass system, the results revealed that the glass samples contain TeO 2 possess higher μ/ρ values than the samples contain SiO 2. For the B 2 O 3 –GeO 2 –Gd 2 O 3 –Eu 2 O 3 –GdF 3 –BaF 2 glasses, we found that the μ/ρ values decrease as BaF 2 is increased from 0 to 15 mol%. Moreover, it is found that 50Sb-0Ge for series 1, TWG0 for series 2, 2G4T for series 3 and X = 0 for series 4 glass samples among the studied glasses have the highest effective atomic number values. On the basis of the results achieved, 50Sb-0Ge, TWG0, 2G4T and X = 0 samples have the best radiation shielding characteristics among the selected glasses. Highlights • Radiation shielding characteristics of different germanate glasses have been investigated. • The μ/ρ for the selected germanate glasses was evaluated by MCNPX simulation code at different energies. • The HVL results for the present germanate glasses suggested that the gamma photons absorption capacity increases as the density of the sample increases. [ABSTRACT FROM AUTHOR]

WRKY transcription factors (TFs) play an important role in regulating plant growth and responses to environmental stress. However, the molecular mechanism of WRKY to cadmium (Cd) stress is unclear, which prevents phytoremediation of Cd-contaminated soil from widely application. To determine the underlying mechanism, PyWRKY48 -overexpressing poplars were obtained (OE-32 and OE-67) to study the Cd tolerance and accumulation in poplars. Results showed that the Cd content in the aboveground part of the two transgenic poplar lines were 1.57 and 1.99 times higher than that of wild type (WT), and lateral roots, GSH, PCs content and GST activity increased significantly. RNA-seq. data about transgenic and WT poplars revealed that 2074 differentially expressed genes (DEGs) in roots, 4325 in leaves, and 499 in both tissues. And these DEGs were mainly concentrated in ABC transport protein (PaABC), heavy-metal binding protein (PaHIPP), and transportation and loading of xylem (PaNPF , PaBSP) proteins, and they enhanced Cd accumulation. Meanwhile, PyWRKY48 increased the Cd tolerance of transgenic poplars by up-regulating the expression of PaGRP , PaPER and PaPHOS , which encode cell wall proteins, antioxidant enzyme, and heavy metal-associated proteins, respectively. In addition, overexpression PyWRKY48 promoted poplar growth by increasing the chlorophyll a nd carotenoid content. This study generated PyWRKY48 -overexpressing poplars and functionally verified them in Cd-contaminated soil, to analyze the effects of the gene on poplar growth, Cd tolerance and Cd accumulation. RNA seq. data revealed that several genes are involved in Cd exposure. This may provide a strong molecular basis and new ideas for improving the phytoremediation efficiency of Cd-contaminated soils. Importantly, the transgenic poplars grew better and accumulated more Cd than the wild-type. Therefore, PyWRKY48 -overexpressing poplars could be considered useful for mitigating environmental pollution. • Overexpressed PyWRKY48 poplars grew better than the wild type. • Overexpressed PyWRKY48 poplars enhanced cadmium tolerance and accumulation. • PaABC , PaHIPP , PaNPF , PaBSP , etc. may involve in cadmium stress induced by PyWRKY48. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid (PFOA) is a representative persistent organic pollutant and its disposal by mechanochemical (MC) technology emerges in recent years. However, degradation mechanism of PFOA especially rupture of C−F bonds during MC process is still unclear. Therefore, we innovatively employed barium titanate as co-milling reagent in MC system to disclose an electron-dominated reduction process. By stimulating piezoelectric effect of BaTiO 3 under MC impact, free electrons were generated. The results implied more than 95.00% degradation and 60.00% defluorination efficiency were obtained after 6 h′ ball milling. DPPH• was used as probe to confirm the existence of piezo-excited electrons, which were further verified to be major reactive species by atmosphere experiments. Thus, PFOA destruction was dominated by reduction process, characterizing by breakage of C−F bonds induced by electrons. Accordingly, the fate of organic fluorides was explored and BaF 2 was identified as final product. The cleavage of carboxyl group initiated PFOA decomposition, following by successive removal of CF 2 groups and elimination of F−. Moreover, the practical experiments and reusable trials implied promising application of this method. Overall, this paper provides a novel perspective for reductive decomposition of PFOA by MC technology and reveals the major role of electrons during reaction process. [Display omitted] • PFOA is reductive degraded in solid phase by MC technology using BaTiO 3. • Free electrons generated by piezoelectric effect is main reactive species. • Organic fluorine detaches from carbon chain and converts into BaF 2. • Effects of soil matrix is systematically evaluated. [ABSTRACT FROM AUTHOR]

The short-wavelength sub-nanosecond luminescence in BaF 2 material, discovered in the early 80s, gave a new direction to research into fast scintillators and phosphors. In contrast to 'typical' luminescence occurring within the forbidden band gap, the new type of emission was due to transitions between the upper core and valence bands. Thus it was named core-valence luminescence (CVL); the terms cross-luminescence and Auger-free luminescence have also been used. Given its unusual nature, this new luminescence process has attracted considerable interest in the field of condensed matter physics. During the sequent decades (till the end of the previous century) CVL has been experimentally observed in several dozen compounds and the conditions for detecting CVL have been established. Interest in this kind of luminescence increased in recent years due to the emergence of new methods of crystal synthesis, the development of high-speed solid-state photodetectors, and the construction of unique modern set-ups using synchrotron radiation. This paper analyzes the numerous studies of CVL, obtained mainly over the past decade. Experimental and theoretical data on this topic are considered in detail. Special attention is given to new results on scintillation characteristics of BaF 2 in the form of single crystals, ceramics, nanoparticles, and composites. The features of CVL in binary and ternary compounds are discussed. Some Cs- and Ba-based ternary halides show relatively high light yields and represent promising fast scintillators. The prospects of using materials with CVL as fast scintillators for time-of-flight positron emission tomography and other applications are deliberated. • Overview of recent theoretical and experimental findings on Core Valence luminescence. • Most attractive CVL crystals for ultrafast scintillator applications analyzed. • Prospects for future studies and underexplored CVL materials listed. [ABSTRACT FROM AUTHOR]

• With the introduction of Tm3+, Dy3+ can achieve broadband emission between 2600 and 3400 nm. • The mid-infrared fluorescence intensity enhanced with the increase of Tm3+ due to the energy transfer process between Dy3+ and Tm3+. • Larger absorption and emission cross-sections the glass owned, the gain coefficient was also greatly improved. • The fluorescence lifetime at 2.9 μm were prolonged with the addition of Tm3+. We report the 2600–3400 nm strong mid-infrared (MIR) fluorescence emission with the full width at half maximum (FWHM) of 355 nm in the zirconium fluoride glass incorporated with Dy3+, Tm3+ ions. In this paper, Dy3+, Tm3+ ions co-doped ZrF 4 -BaF 2 -LaF 3 -AlF 3 -YF 3 zirconium fluoride glasses are synthesized by high temperature melting method. Structure information is obtained by raman spectroscopy, and the maximum phonon energy of the synthesized glass is 575 cm−1. Optical performance is mainly characterized by transmission spectrum, absorption spectrum and emission spectrum, theoretical analysis is described by Judd-Ofelt (J-O) theory, cross sections and gain coefficient. Under the 808 nm Laser Diode (LD), the 2.9 μm mid-infrared emission intensity is significantly enhanced with the introduction of Tm3+, and the fluorescence lifetime is prolonged 1.85 ms, the relevant energy transfer mechanism has been further analyzed. All results show that the new glass material may be a potential medium for mid-infrared broadband fiber amplifiers and lasers. [ABSTRACT FROM AUTHOR]

• A boron-adjustment-free (BAF) control strategy was proposed for large PWRs. • A blocking logic for three independent control banks was first designed. • The strategy can realize the BAF load-follow operations of PWRs. • The blocking logic provides better AO control than that under MSHIM strategy. This paper proposes an advanced boron-adjustment-free (BAF) control strategy for large pressurized water reactors (PWRs). The strategy combines the advantages of fast power compensation of the boron-adjustment Mode-G control strategy with the closed-loop axial offset (AO) control through control rods in the Mechanical Shim (MSHIM) control strategy. It can achieve fast power compensation, exact coolant average temperature control, and automatic AO control through three independently-moving control banks, respectively. Also, to avoid mutual interference between the core power and AO control, a novel blocking logic for the three control banks was developed. Simulation results of a large PWR implementing the BAF control strategy indicate satisfactory load-follow capabilities of the reactor without the need to adjust boron concentration. Moreover, the proposed blocking logic can provide better AO control without compromising reactor power control than that referring the blocking logic of reactor power and AO control banks in the MSHIM control strategy. [ABSTRACT FROM AUTHOR]

Urbanisation processes as a result of population growth, migration and infrastructure initiatives have a direct impact to cultural heritage sites. This paper aims to monitor growth dynamics of the urbanisation process that took place in the Paphos district, southwest Cyprus during the last decades, and evaluate its impact to monuments and archaeological sites. In this extensive area, several important archaeological sites and monuments are found, while some of them are also listed in the UNESCO catalogue of World Cultural Heritage sites. GIS and remote sensing techniques have been used in order to map the listed monuments in the Paphos District, as well as to record spatial and temporal land use changes since the 1980s. The spatial patterns of urban sprawl are studied and analysed using archive time series medium resolution Landsat ETM+ and TM satellite imagery. In addition, a DMSP-OLS night-ime image was also used. Several supervised and unsupervised classification algorithms have been evaluated and examined for this purpose. Additionally, Markov equation were applied in an attempt to predict future urban expansion The final outcomes revealed that a dramatic increase of the urban areas took place in the last years in Paphos district, and as a result significant pressure is expected on archaeological sites found in the peri-urban areas. [ABSTRACT FROM AUTHOR]

Aquatic contamination can settle into sediments, where it complexes with organic matter and becomes bioavailable. The resulting bioaccumulation of these contaminants by benthic fauna poses a serious threat due to the potential for trophic transfer. This paper offers an insight into the heterogenous accumulation behavior of different elements, and the consequences for ecological risk. In this study, we present field quantification of sediment-associated bioaccumulation factors (BAF S) in freshwater benthic macroinvertebrates. 17 elements were quantified using ICP-MS in sediment and Asellus aquaticus and Gammarus sp. samples. Previously published reports of contaminant concentrations in freshwater and marine sediments and benthic fauna were likewise analyzed to provide a complementary picture of bioaccumulation across contaminants and taxa. We demonstrate that the BAF S correlates strongly with the thiophilicity of the elemental contaminants, as defined by (Kepp, 2016), for all strata examined. These findings support the hypothesis that thiol-mediated processes, such as that of metallothionein, play a larger role in bioaccumulation than typically afforded. In conclusion, we demonstrate the potential for the thiophilic scale to act as a predictor of accumulation potential. [Display omitted] • Accumulation correlates strongly with thiophilicity across orders and environments. • Results support a thiol-based bioaccumulation process. • Bioavailability of contaminants can be predicted using the thiophilic scale. [ABSTRACT FROM AUTHOR]

The paper describes the effect of high effective atomic number (Z eff) materials loading in polystyrene based thin-film Plastic Scintillators (PS). Thin plastic scintillator sheets have been loaded with high Z materials such as BaFBr:Eu, Gd 2 O 2 S:Tb, Gd 2 O 3 , BaF 2 , CeO 2 and Bi 2 O 3. Polystyrene based PS sheets of 250 ± 50 μ m thickness have been prepared by dissolving predetermined quantities of polystyrene, 2,5-Diphenyloxazole (PPO) and 1,4-bis(5-phenyl-2-oxazolyl) benzene (POPOP) in the p-xylene solvent. High Z eff material powders of 23 μ m size are mixed in the plastic scintillator solution and coated over the cellulose acetate-based transparency sheets. The dried films are peeled off, and their photoluminescence, radioluminescence, pulse height spectrum and response to alpha, beta, gamma and neutron radiations are studied by adopting suitable methods. The high Z eff materials for loading in PS are selected based on their physical properties like refractive index, bandgap, Z eff , Photoluminescence (PL) properties. While the composite scintillator loaded with 14.3 wt% of BaFBr:Eu2+ showed significant increase compare to other high Z materials. The loading concentration has been optimized as 14.3 wt% from the BaFBr:Eu2+ studies. Most of the composite scintillators showed improvement in radioluminescence and pulse height spectra for different radiations. • Polystyrene based thin plastic scintillator have been prepared by solvent-based fabrication method. • Thin composite plastic scintillator are studied with high Z eff material loading. • High Z eff material loaded composite scintillators showed enhanced response to radiation. • BaFBr:Eu loaded composite PS has shown the best promising result. [ABSTRACT FROM AUTHOR]

This paper describes the preparation and characterization of various concentrations of Nd3+ doped B 2 O 3 –BaF 2 –PbF 2 –Al 2 O 3 (BaPbAlFB) glasses in detailed. The glasses used in the present work are synthesized by using melt quenching process and characterized by measuring the absorption, photoluminescence (PL) and PL decay spectral profiles. The energies of the absorption spectral profiles called oscillator strengths are evaluated from the absorption spectra and subjected to Judd-Ofelt (J-O) theory to evaluate the J-O intensity parameters using least squares fit method. Under 808 nm diode laser excitation, the BaPbAlFBNd glasses exhibit three emission bands at near-infrared region around 887, 1063, 1336 nm from 4F 3/2 → 4I 9/2, 4I 11/2 and 4I 13/2 radiative transitions respectively. Among the three emissions, the one observed at 1063 nm is found to be more intense relatively. The lifetime of 4F 3/2 transition has been estimated experimentally through decay measurements recorded under 808 nm excitation wavelength. Among all the BaPbAlFB glasses investigated, the one with 1.0 mol% of Nd3+ ions is showing relatively high fluorescence quantum efficiency. The measured saturation intensity (I S) values shows relatively the low threshold values. The obtained results endorsed the potentiality of BaPbAlFBNd1.0 glass for the fabrication of fiber amplifiers and solid-state lasers that can act in NIR region at 1063 nm wavelength. • The J-O intensity parameters of the glass samples. • Experiment lifetimes are calculated from decay measurements. • The evaluation of absorption cross section, emission cross section and gain cross section. • The figure of merit and saturated intensity are calculated. • NIR laser emission near 1.063 μm was obtained. [ABSTRACT FROM AUTHOR]

• Easy method to remove the cupping layer covering the topological insulator. • Using glue to remove the cupping layer. • Surface modification of MBE topological insulator. The topological categorization originates from a depiction of the sequencing of bands around the band gap of the material in comparison to the normal vacuum type band ordering. The structure can either be normal or inverted, and thus topologically trivial or non-trivial. An odd number of Dirac fermions on the surface occurs in this type of material. Time-reversal symmetry is responsible to preserve the surface bands. On the other hand, topological crystalline insulator is protected by mirror symmetry; this system has an even number of Dirac surface state per BZ. Capping layer of Te or Se is necessary due to the high sensitivity of films surfaces to atmospheric pressure. The capping layer works as a protection from oxidation. In Bi 2 Te 3 samples, the bonds between Bi and Te are covalent bonds while the bonds between Te-Te at a certain position are van der Waals bonds. Thereby, the bonds between amorphous Te cap and sample surface is weaker than van der Waals bonds within the sample structure. However, the top boost cleaving method was successful. But, for Pb 1-x Sn x Te samples the top boost cleaving method unsuccessfully results. The bonds between the metallic Pb 1-x Sn x Te sample surface and amorphous Te cap are stronger than van der Waals bonds in BaF 2 substrate, i.e. F-F van der Waals bonds. In this paper, we present different techniques to recover fresh surfaces, from classical methods (such as sputtering and annealing) working for all types of films and top boost methods, which could be less used due to the strong bonds in some films. Moreover, we were able to recover the immaculate surfaces for non-capped samples. We present here in a systematic study by low energy electron diffraction (LEED), x-ray photoemission spectroscopy (XPS), and angle-resolved photoemission spectroscopy (ARPES). [ABSTRACT FROM AUTHOR]

• A simultaneous denitrification and biogas desulfurization process (SDBD) was proposed. • 0.9%–1.5% hydrogen sulfide in biogas was completely removed. • More than 85% COD, 98% NH 4 +-N and 81.65% TN was removed from real domestic sewage. • Hydrogen sulfide introduction altered the pathway of nitrate removal. • Economic assessment enables SDBD system to be a promising way in biological N removal. This paper proposed a novel simultaneous denitrification and biogas desulfurization (SDBD) process for domestic sewage treatment and biogas upgrading. The process consisted of an expanded granular sludge bed (EGSB) for integrated autotrophic and heterotrophic denitrification (IAHD) and a biological aerated filter (BAF) for nitrification. The experiments were firstly conducted to investigate the performance of the lab-scale SDBD system with real domestic sewage at various hydraulic retention times (HRT). The system successfully achieved 83.0 ± 1.8% chemical oxygen demand (COD), 96.2 ± 1.8% ammonia (NH 4 +-N) and 67.3 ± 4.1% total nitrogen (TN) removal efficiency without biogas introduction, and the optimal HRT of EGSB and BAF was determined to be 6 h and 4 h, respectively. Then, biogas with three different hydrogen sulfide concentrations (1.5%, 1.2% and 0.9%) was introduced into the system. Almost complete removal of hydrogen sulfide in biogas was achieved in all the tested scenarios and the removal efficiency of COD, NH 4 +-N and TN maintained at around 86.8%, 98.4% and 83.4%, respectively. Microbial community analysis results showed that biogas introduction notably increased the bacterial diversity and particularly enriched the nitrate-reducing, sulfide-oxidizing bacteria, which forms the major contribution to the hydrogen sulfide removal in the system. Finally, we put the SDBD system in the whole treatment system of domestic sewage and discussed its economics. The results indicated that the total operating cost of sewage treatment plant could be saved to 0.59 RMB/m3, which proved SDBD system to be a promising alternative way in biological nitrogen removal and biogas desulfurization. [ABSTRACT FROM AUTHOR]

In this paper, the upconversion (UC) emission of Tm3+/Cr3+/Yb3+ tri-doped in SiO 2 –AlF 3 –BaF 2 –La 2 O 3 transparent fluorosilicate glass-ceramics (SGC) containing Ba 2 LaF 7 nanocrystals were investigated. The enhancement of red UC emission of Tm3+/Cr3+/Yb3+ tri-doped in SiO 2 –AlF 3 –BaF 2 –La 2 O 3 transparent SGC were also investigated. Through the energy transfer processes between Cr3+ and Tm3+, and the combination of Cr3+-Tm3+ led to the red UC emission intensity of Tm3+/Cr3+/Yb3+ tri-doped transparent SGC bands centered at ~806 and ~858 nm has been significantly enhanced. The CIE chromaticity coordinates for UC emission of Tm3+/Cr3+/Yb3+ tri-doped in SGC-0.2Tm1Cr2Yb transparent SGC sample is calculated (x = 0.704; y = 0.296) and the UC emission of Tm3+/Cr3+/Yb3+ tri-doped in SiO 2 –AlF 3 –BaF 2 –La 2 O 3 transparent SGC has been identified in red color region of CIE chromaticity coordinates. In addition, the ET processes between Cr3+ and Tm3+ are also proposed and discussed. [ABSTRACT FROM AUTHOR]

Our recent study was focused on the emission from Laser Induced Plasma (LIP) at the delay times of tenths of microseconds after the laser pulse. At these long delays, the spectrum is dominated by the broadband molecular emission and plasma induced luminescence (PIL) produced by a luminescent matrix; only solitary atomic emission lines can be seen. Barium fluoride BaF 2 activated by thulium (Tm) is a famous scintillator that presents the promising object for LIP in terms of both the potential for BaF molecular emission and Tm3+ PIL. The detection of molecular and PIL bands presents a new opportunity for analysis of halogens and rare-earth elements, which are the difficult objects for LIBS. In this paper, we show that the UV, Green, Extreme Red, and Infrared molecular bands from BaF and blue luminescence from Tm3+ are present in the LIP emission spectra while the detection of atomic emission from F I and Tm I was impossible with the same experimental setup. Thus, the detection of molecular emission and PIL can be more sensitive than the traditional detection of emission from atoms and ions. Unlabelled Image • We studied LIBS of BaF 2 activated by Tm3+. • Emission and temporal behavior of BaF molecules were determined. • Plasma Induced Luminescence of Tm3+ was found. [ABSTRACT FROM AUTHOR]

• Ba 2 ZrF 8 and BaTiF 6 fluorides are precipitated from the spent liquors using BaF 2. • The heating of Ba 2 ZrF 8 (BaTiF 6) + Mg + k Cu mixtures yield a self-ignition at 600 °C. • CuTi and CuZr alloy ingots and BaMgF 4 slag are produced after the heating process. • The chemistry of liquor purification and CuTi (CuZr) ingots formation is highlighted. In this paper, we describe a progressive two-step process that allows titanium and zirconium fluorides (TiF 4 , ZrF 4) contained in spent liquors of etched Ti and Zr alloys to be effectively recycled into CuTi and CuZr alloy compositions and a regenerated pickling acid of high purity. In the first step, spent pickling liquor is treated with a BaF 2 suspension to produce water-insoluble BaTiF 6 and Ba 2 ZrF 8 fluoride salts. In the second step, the as-precipitated BaTiF 6 and Ba 2 ZrF 8 fluoride salts are mixed with Mg and Cu metals powder and heat-treated at 1300 °C to produce CuTi and CuZr alloy ingots. The microstructures of the ingots are discussed in regard to Cu concentration. [ABSTRACT FROM AUTHOR]

• Dy3+: ZBAN glass was synthesized and satisfactory white fluorescence was obtained. • The trend of fluorescence color coordinate is estimated by J–O parameters. • Chroma difference in CIELAB coordinates was used to evaluate fluorescence. • Energy of Dy3+: ZBAN glass fluorescence is close to that of white light. In this paper, we reported the white light emission properties of Dy3+ doped ZrF 4 -BaF 2 -AlF 3 -NaF (ZBAN) glass. Physical properties of the host glass were examined. The intensity parameters were determined from Judd–Ofelt theory based on the absorption spectrum. The chromaticity coordinates calculated using emission spectrum are located in the white area of the CIE chromaticity diagram. Judd–Ofelt theory was used to analyze the relationship between the Dy3+ doping concentration and the yellow/blue ratio of the fluorescence. Furthermore, the change of chromaticity coordinates in the CIE chromaticity diagram was predicted. Anomalous change caused by fluorescence quenching at high concentrations was also discussed. In order to find the fluorescence closest to the equal energy light, the chroma difference between the fluorescence and the equal energy point was calculated. These results demonstrate that Dy3+ doped fluoride glass is a suitable material for use as a standard white light source. [ABSTRACT FROM AUTHOR]