Phosphor Powders Research Articles

High efficiency and stable La3Si6N11:Ce phosphor-in-glass film for high power laser lighting

As an inorganic color conversion material, phosphor-in-glass film (PiF) has received extensive attention in the sphere of laser-driven white lighting due to its excellent integrated performance. The yellow-emitting phosphor La3Si6N11:Ce has excellent thermal stability and wide emission band, which makes it more competitive than Y3Al5O12:Ce in laser-driven white lighting. Herein, we embedded La3Si6N11:Ce phosphor powder in a silicate glass matrix (SiO2–B2O3–CaO–Na2O) and sintered it on a sapphire substrate. In the silica-rich glass system, the network structure of silica-oxygen tetrahedral glass is more rigid and the thermal erosion of the phosphor by the silica-based glass is less, which makes the phosphor maintain better performance after low-temperature co-sintering. The quantum efficiency in the optimized LSN phosphor-in-glass film (LSN PiF) is up to 81 %, and the thermal conductivity is 10.2 Wm−1K−1, showing good thermal stability. Impressively, the LSN PiF produces a bright near-white light (0.3323,0.346) at a blue laser of 5.6 W, with corresponding luminous efficiency up to 195 lm/W. Moreover, LSN PiF can maintain about 80 % of the initial luminous intensity after continuous lighting for 24 h at the incident power of 3.5 W. These outstanding properties can advance the development of LSN phosphors in high power laser lighting applications.

Optical Properties of Spherical YAG:Ce<sup>3+</sup> Phosphor Powders Synthesized by Atmospheric Plasma Spraying Method Appling PVA Solution Route and Domestic Aluminium Oxide Seed

Optical Properties of Spherical YAG:Ce<sup>3+</sup> Phosphor Powders Synthesized by Atmospheric Plasma Spraying Method Appling PVA Solution Route and Domestic Aluminium Oxide Seed

Rational Design of Dual‐Mode Emitting Carbon Dots to Exploit the Synergistic Effect of Matrices for High‐Efficiency WLEDs and Anti‐Counterfeiting

AbstractLong‐lived room‐temperature phosphorescence (RTP) materials have been widely applied in various fields. However, achieving high‐performance carbon dots (CDs) RTP remains a great challenge. Here, a facile synthetic strategy is rationally designed for the synthesis of high‐performance dual‐mode emitting CDs by constructing rigid structures through the synergistic effect of the matrices. The obtained CD RTP powder possesses an ultrahigh photoluminescence quantum yield (PLQY) of 70.7%, a phosphorescence lifetime of about 0.45 s, and an afterglow that lasts for 15 s to the naked eyes. Most importantly, the prepared CD RTP powder can be utilized as a commercial phosphor powder for the fabrication of a high‐performance white lighting‐emitting diode (WLED) with a CIE coordinate of (0.39, 0.39), a high color rendering index of 93.6, and a color temperature of 3805 K for warm WLED. Especially the luminous efficiency of the fabricated WLED can reach up to 66.89 lm W−1, which is much higher than the values reported for most CDs‐based WLED devices. Additionally, CD RTP can be applied to advanced invisible inks for information encryption due to its excellent water solubility and can also be exploited for advanced information anti‐counterfeiting by utilizing phosphorescent properties.

Photoluminescence and structural properties of Ce3+ and Eu3+ Co-doped Gd2SiO5 phosphor powders

Photoluminescence and structural properties of Ce3+ and Eu3+ Co-doped Gd2SiO5 phosphor powders

Crystallization of Na2SrGe6O14:Cr3+,Yb3+ Glass Ceramics Enabling a Watt‐Level Output Power NIR‐I/NIR‐II Lighting Source

AbstractNear‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) lighting sources are applied in non‐destructive examination and illumination supplements for night monitoring. As a critical component of NIR pc‐LED, NIR phosphors are required to possess a high external quantum efficiency (EQE), super thermal stability, and broadband emission to meet applications. Here, Na2SrGe6O14:Cr3+ (NSGO:Cr) glass ceramics (GC) bulk via highly crystallization from glass precursor is fabricated and demonstrates an ultrabroad emission band centered at 815 nm with a full width at half‐maximum (FWHM) of 214 nm and a high EQE of 49.2%. Moreover, Yb3+ co‐doping significantly enhances Cr3+ → Yb3+ energy transfer (ET) due to the stronger Yb3+: 2F7/2‐2F5/2 absorption. Benefiting from the ET process, the Cr/Yb co‐doped GC exhibits NIR‐I/II emission with improved thermal stability from 30.1% to 65.0%. Furthermore, an encapsulant‐free NIR GC‐converted LED (GCc‐LED) is prepared and exhibits 52.2 mW NIR output power with a high photoelectric conversion efficiency (PCE) of 19.4%. Under a large current of 600 mA, the NIR device exhibits a watt‐level output power of 922.4 mW with a PCE of 9.1%. Compared to conventional NIR powder phosphors, NSGO:Cr/Yb GC with high performance can open up an avenue for the fabrication of high power NIR lighting sources.

The effect of supplementing the calcium phosphate cement containing poloxamer 407 on cellular activities.

Calcium phosphate cement (CPC) is generally used for bone repair and augmentation. Poloxamers are tri-block copolymers that are used as surfactants but have applications in drug and antibiotic delivery. However, their biological effects on bone regeneration systems remain unelucidated. Here, we aimed to understand how supplementing the prototype CPC with poloxamer would impact cellular activity and its function as a bone-grafting material. A novel CPC, modified beta-tricalcium phosphate (mβ-TCP) powder, was developed through a planetary ball-milling process using a beta-tricalcium phosphate (β-TCP). The mβ-TCP dissolves rapidly and accelerates hydroxyapatite precipitation; successfully shortening the cement setting time and enhancing the strength. Furthermore, the addition of poloxamer 407 to mβ-TCP could reduce the risk of leakage from bone defects and improve fracture toughness while maintaining mechanical properties. In this study, the poloxamer addition effects (0.05 and 0.1 g/mL) on the cellular activities of MC3T3-E1 cells cultured in vitro were investigated. The cell viability of mβ-TCP containing poloxamer 407 was similar to that of mβ-TCP. All specimens showed effective cell attachment and healthy polygonal extension of the cytoplasm firmly attached to hydroxyapatite (HA) crystals. Therefore, even with the addition of poloxamer to mβ-TCP, it does not have a negative effect to osteoblast growth. These data demonstrated that the addition of poloxamer 407 to mβ-TCP might be considered a potential therapeutic application for the repair and regeneration of bone defects.

Influence of Ag and/or Sr Dopants on the Mechanical Properties and In Vitro Degradation of β-Tricalcium Phosphate-Based Ceramics.

β-tricalcium phosphate has good biodegradability and biocompatibility; it is widely perceived as a good material for treating bone deficiency. In this research, different contents of strontium (Sr) and silver (Ag) ion-doped β-tricalcium phosphate powders were prepared using the sol-gel method. After obtaining the best ratio of pore-forming agent and binder, the as-synthesized powders were sintered in a muffle for 5 h at 1000 °C to obtain the samples. Then, these samples were degraded in vitro in simulated body fluids. The samples were tested using a series of characterization methods before and after degradation. Results showed that the amount of Sr and/or Ag doping had an effect on the crystallinity and structural parameters of the samples. After degradation, though the compressive strength of these samples decreased overall, the compressive strength of the undoped samples was higher than that of the doped samples. Notably, apatite-like materials were observed on the surface of the samples. All the results indicate that Sr and/or Ag β-TCP has good osteogenesis and proper mechanical properties; it will be applied as a prospective biomaterial in the area of bone repair.

Novel Double Hybrid-Type Bone Cements Based on Calcium Phosphates, Chitosan and Citrus Pectin.

In this work, the influence of the liquid phase composition on the physicochemical properties of double hybrid-type bone substitutes was investigated. The solid phase of obtained biomicroconcretes was composed of highly reactive α-tricalcium phosphate powder (α-TCP) and hybrid hydroxyapatite/chitosan granules (HA/CTS). Various combinations of disodium phosphate (Na2HPO4) solution and citrus pectin gel were used as liquid phases. The novelty of this study is the development of double-hybrid materials with a dual setting system. The double hybrid phenomenon is due to the interactions between polycationic polymer (chitosan in hybrid granules) and polyanionic polymer (citrus pectin). The chemical and phase composition (FTIR, XRD), setting times (Gillmore needles), injectability, mechanical strength, microstructure (SEM) and chemical stability in vitro were studied. The setting times of obtained materials ranged from 4.5 to 30.5 min for initial and from 7.5 to 55.5 min for final setting times. The compressive strength varied from 5.75 to 13.24 MPa. By incorporating citrus pectin into the liquid phase of the materials, not only did it enhance their physicochemical properties, but it also resulted in the development of fully injectable materials featuring a dual setting system. It has been shown that the properties of materials can be controlled by using the appropriate ratio of citrus pectin in the liquid phase.

Effect of Ga3+ substitution on the photoluminescence properties of ZnAl2O4 red phosphor

In this work, a series of ZnAl(1.99-x)GaxO4:0.5%Cr3+ (x = 0, 0.1, 0.3, 0.5, and 0.7) phosphor powders were prepared by a solid-phase reaction. As the Ga3+ doping concentration increased, the crystal field strength Dq/B gradually decreased from 2.778 to 2.648, indicating a progressive weakening of the octahedral field strength. In result, red shift and spectral broadening have been observed in the photoluminescence excitation (PLE) and photoluminescence (PL) spectra of the Ga3+ substituted samples. Compared with ZnAl1.99O4:0.5%Cr3+, the PL spectrum of ZnAl1.49Ga0.5O4:0.5%Cr3+ was wider and the full width at half maximum (FWHM) was increased from 23.2 nm to 31.8 nm. And the PL intensity was increased by 1.8 times. Due to Ga3+ incorporation into the ZnAl2O4 lattice, the [AlO6] octahedron was expanded, which provides a more suitable coordination environment for Cr3+, and the PL thermal stability was increased from 65% to 70% at 150 °C. These results show that appropriate replacement of Al3+ by Ga3+ effectively improves the PL performance of ZnAl1.99O4:0.5%Cr3+ red phosphor and makes up the red component deficiency of pc-WLEDs singly based on the YAG:Ce3+ phosphor.

Blue/NIR-emitting Phosphor Based on Sr2CeO4: Tm3+, Yb3+ Obtained by Combustion Synthesis

In this study, pure Sr2CeO4 (SCO) and codoped Sr2CeO4:Tm3+, Yb3+ (SCO:Tm, Yb) of powder phosphors were synthesized by a combustion technique. The concentration of Tm3+ was fixed at 0.5 mol %, while the Yb3+ doping concentration was varied from 0 to 7.0 mol %. The crystalline structure, morphology and luminescence properties were studied using X-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence spectroscopy, respectively. The XRD analysis shows the crystalline orthorhombic phase for all synthesized samples of SCO and SCO: Tm, Yb. The SEM results show that the doped sample with 5.0 mol % Yb3+ has the lowest grain particle size of 1.92 mm. The SCO:Tm, Yb phosphors produce mainly blue and near infrared emission bands centered at 481 nm and 813 nm (under 980 nm, excitation) which corresponds respectively to 1G4→3H6 and 3H4→3H6 transitions of Tm3+. In addition, the international commission on illumination CIE coordinates were calculated for all samples taking the range of 400 – 700 nm obtaining for the 5.0 mol % Tm3+ doped sample the coordinates: (x,y) = (0.0833, 0.1671) which match with pure blue color. Due to the strong blue and near infrared emissions, the SCO:Tm, Yb phosphors could be good candidates for use in biomarkers or lighting applications.

Nutrient-Doped Hydroxyapatite: Structure, Synthesis and Properties

Complex inorganic powders based on calcium phosphates have found a plethora of practical applications. Of particular interest are the CaO-P2O5 system-based multi-component material powders and granules as the source of major- and micronutrients for the plants. The emerging strategy is to use nano fertilizers based on hydroxyapatite (HAP) for phosphorus and other nutrient delivery. The doping of micronutrients into HAP structure presents an interesting challenge in obtaining specific phase compositions of these calcium phosphates. Various techniques, including mechanochemical synthesis, have been employed to fabricate doped HAP. Mechanochemical synthesis is of particular interest in this review since it presents a relatively simple, scalable, and cost-effective method of calcium phosphate powder processing. The method involves the use of mechanical force to promote chemical reactions and create nanometric powders. This technique has been successfully applied to produce HAP nanoparticles alone, and HAP doped with other elements, such as zinc and magnesium. Nanofertilizers developed through mechanochemical synthesis can offer several advantages over conventional fertilizers. Their nanoscale size allows for rapid absorption and controlled release of nutrients, which leads to improved nutrient uptake efficiency by plants. Furthermore, the tailored properties of HAP-based nano fertilizers, such as controlled porosity and degradation levels, contribute to their effectiveness in providing plant nutrition.

Bulk‐Size and Highly Transparent Composite Phosphor for NIR Spectroscopy

AbstractNear‐infrared (NIR) phosphors offer a novel luminescent solution for NIR spectroscopy, but their efficiency remains low. Herein, it is demonstrated that the high transparency of a phosphor improves its external quantum efficiency by developing a new inorganic–organic composite phosphor. The new bulk‐size and highly transparent composite phosphor is fabricated through layer‐by‐layer assembly of micron‐sized hexagonal LiSrAlF6:Cr3+ powder phosphor. The inline transparency of the final bulk phosphor can be controlled from 0% to 90.2% at a large solid concentration of ≈47 vol.%. With high transparency, the new bulk phosphor allows the phosphor‐conversion light‐emitting diode (pc‐LED) a 2.9 times improvement in efficiency. This paper inspires a feasible and low energy consumption method to facilitate next‐generation NIR pc‐LED phosphors.

Aqueous Calcium Phosphate Cement Inks for 3D Printing

Mimicking the native properties and architecture of natural bone is a remaining challenge within the field of regenerative medicine. Due to the chemical similarity of calcium phosphate cements (CPCs) to bone mineral, these cements are well studied as potential bone replacement material. Nevertheless, the processing and handling of CPCs into prefabricated pastes with adequate properties for 3D printing has drawbacks due to slow reaction times, limited design freedom, as well as fabrication issues such as filter pressing during ejection through thin nozzles. Herein, an aqueous cement paste containing α‐tricalcium phosphate powder is proposed, which is stabilized by sodium pyrophosphate (Na4P2O7·10H2O) as additive. Since high powder loadings within pastes can result in filter pressing during extrusion, various concentrations and molecular weights of hyaluronic acid (HyAc) are added to the cement paste, resulting in reduced filter pressing during 3D extrusion‐based printing. These cement pastes are investigated regarding their setting reaction after activation with orthophosphate solution by isothermal calorimetry and X‐ray diffraction, as well as their hardening performance using Imeter measurements, while the processability is assessed by extrusion through 1.2 and 0.8 mm cannulas. The 3D‐printed structures with appropriate HyAc molecular weight and concentration demonstrate suitable mechanical properties and resolution for clinical application.

Lithium iron phosphate with high-rate capability synthesized through hydrothermal reaction in low Li concentration solution

Lithium iron phosphate (LiFePO4) is one of the most important cathode materials for high-performance lithium-ion batteries in the future due to its high safety, high reversibility, and good repeatability. However, high cost of lithium salt makes it difficult to large scale production in hydrothermal method. Therefore, it is urgent to reduce production costs of LiFePO4 while maintaining the unique advantages of hydrothermal methods. In this work, the lithium iron phosphate powders (LFP-twi) with low Fe-Li anti-site defect concentration and inhibition along the direction [010] was constructed by hydrothermal reaction with low lithium usage. As a result, this allows the material to have an excellent reversible capacity (163.6 mAhg−1 at 0.1 C), ultra-high-rate capability (120 mAhg−1 at 10 C), and noticeable low-temperature performance (130 mAhg−1 at - 20 ℃ and 0.1 C). These findings open a new avenue for the development of high-density current and low-temperature resistant LiFePO4 batteries.

Direct microwave leaching conditions of rare earth elements in fluorescent wastes

The luminescent phosphor powder in the fluorescent lamp constitutes 2% of the lamp’s weight. It can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth oxides. In the present study, microwave leaching process was conducted to dissolve rare earth elements yttrium (Y), europium (Eu), and remaining rare earth elements (REEs) present in the phosphor powder of the fluorescent lamp, and the yields were compared. In the microwave leaching process, the effects of the temperature (80–160°C), acid type (hydrochloric acid (HCl), nitric acid (HNO3), sulphuric acid (H2SO4)), acid concentration (0.5–6 mol/L), solid to liquid ratio (0.1:10–0.5:10) and reaction time (5–90 min) parameters on leaching efficiencies of varying rare earth elements and calcium were investigated. The highest yield was obtained in the direct microwave leaching of fluorescent waste with the experimental conditions of 6 mol/L HCl, 160 °C, 0.1:10 solid-to-liquid ratio (S:L), and 90 min. Activation energy calculations were made, and kinetic models of the reactions were obtained, and it is observed that Y and Eu dissolution is diffusion-controlled, on the other hand, lanthanum (La), cerium (Ce), and terbium (Tb) were examined to be chemical reaction controlled. Moreover, calcium (Ca) and gadolinium (Gd) seem coherent with the mixed model. Concurrently, mathematical models of all experimental studies are created with the response surface Box-Behnken method and the correlation coefficients of all the models are over 90%.

Luminescence properties of Tb3+/Eu3+ ions activated LiLaSiO4 phosphors for solid-state lighting and flexible display applications

The synthesis and luminescence properties of Tb3+ and Eu3+ single- and co-doped LiLaSiO4 (LLSO) phosphors with energy transfer mechanisms were reported. The rare-earth ions doped LLSO phosphors were synthesized via a solid-state reaction method and their physical characterizations such as phase purity, surface morphology, and elemental analysis were investigated systematically. For the Tb3+ and Eu3+ single- and co-doped LLSO phosphors, their photoluminescence (PL) properties were studied in detail. The LLSO:Tb3+ and LLSO:Eu3+ single-doped phosphors showed superior red and green emissions due to 5D4→7F5 and 5D0→7F2 in the optimized characteristic electronic transitions under ultraviolet (UV) irradiation, respectively. The luminescence performances for both the LLSO:Tb3+ and LLSO:Eu3+ phosphors were optimized at 0.125 mol of doping ion concentration. Under UV excitation, by adjusting the Eu3+ ion concentration in LLSO:0.125Tb3+/Eu3+ phosphors, the tunable emissions from green to red via yellow-orange were obtained. Thus, the tunable emission spectra and luminescence decay lifetimes with increasing the doping content of acceptor ions (Eu3+) confirmed an efficient energy transfer from Tb3+ to Eu3+ ions in the co-doped samples. The critical distance between Tb3+ and Eu3+ was determined to be 13.26 Å and the energy transfer mechanism from Tb3+ to Eu3+ ions was demonstrated to be a dipole-dipole mechanism interaction. In addition, the temperature-dependent PL study was carried out for the LLSO:0.125Tb3+/0.025Eu3+ co-doped phosphor sample and it showed better thermal stability against the temperature quenching. The Tb3+ and Eu3+ single- and co-doped LLSO/polydimethylsiloxane (PDMS) flexible composite films were fabricated by mixing the phosphor powders and PDMS solution. Benefiting from the effective protection of the PDMS matrix, the luminescence stability of the composite films was greatly enhanced. Based on the excellent properties of the synthesized phosphors, Tb3+ and Eu3+ single-doped and Tb3+/Eu3+ co-doped LLSO phosphors could serve as a single-phase multicolor-emitting phosphor under UV excitations.

Biorecovery of rare earth elements from fluorescent lamp powder using the fungus Aspergillus niger in batch and semicontinuous systems

Rare earth elements (REE) are essential in the manufacture of high-technology goods. Tons of wastes containing REE are yearly accumulated; however, environmentally friendly recycling methods are poorly studied. The use of heterotrophic microorganisms could be particularly relevant in the bioleaching of wastes transforming insoluble REE-bearing compounds into more soluble forms which are directly and/or indirectly involved in their metabolism. In this study, bioleaching of rare earth elements from fluorescent phosphor powder in fluorescent tubes using Aspergillus niger CECT2807 was investigated. Bioleaching experiments were performed in batch cultures at 1% pulp density. The concentrations in solution reached 122 mg/l of Y, 8.50 mg/l of Eu, 0.95 mg/l of Ce, 0.40 mg/l of Tb and 1.11 mg/l of La, after 7 days. Then, REE precipitated due to the generation of oxalic acid by the fungus. The residues generated were analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) and the lamp powder biotransformation was evidenced. Additionally, semicontinuous experiments were conducted and evidenced significant increase of REE dissolution rate in static conditions. The amount of extracted REE under static conditions reached 16.5 mg of Y and 0.75 mg of Eu per gram of fluorescent lamp powder.

Al2O3–Ce:YAG composite phosphor ceramics for white laser lighting: Novel preparation and regulatable properties

AbstractIn this work, a series of Al2O3–Ce:YAG phosphor powders were synthesized by regulating the excess Al3+ of (Y,Ce)3Al5O12 via coprecipitation method for the first time, where Al3+, Ce3+, and Y3+ elements were uniformly distributed. With the increase of Al3+ content, the morphology of the powders changed from wormlike shapes to flaky shapes, and Y3Al5O12 phases had a tendency to convert to YAlO3 phases. The x wt.% Al2O3–(Y0.999Ce0.001)3Al5O12 (x = 20, 30, 40, 50, 60, and 70) composite phosphor ceramics (CPCs) were obtained by vacuum sintering (1775°C × 10 h), where Al2O3 and Ce:YAG phases were also well‐distributed. When the Al2O3 content was 30–40 wt.%, the average grain size of Al2O3 was close to that of Ce:YAG. A solid‐state laser lighting device was constructed by a 450 nm laser source and CPCs in a reflection mode. By adjusting the laser power, the correlated color temperature (CCT) values of white laser diodes (LDs) were achieved close to the standard white light of 6500 K. Impressively, the white LDs equipped with the 40 wt.% Al2O3‐containing CPCs showed the optimum CCT of 6498 K (color coordinates: 0.31 and 0.38), as well as a high luminous flux of 1169 lm and efficiency of 166 lm/W at the LD power of 7.05 W. This work has provided a potential idea to optimize the composition uniformity of Al2O3–Ce:YAG CPCs as also to explore their excellent performance in the application of white laser lighting.

Bridging the Green Gap: Monochromatic InP-Based Quantum-Dot-on-Chip LEDs with over 50% Color Conversion Efficiency.

Solid-state light-emitting diodes (LEDs) emit nearly monochromatic light, yet seamless tuning of emission color throughout the visible region remains elusive. Color-converting powder phosphors are therefore used for making LEDs with a bespoke emission spectrum, yet broad emission lines and low absorption coefficients compromise the formation of small-footprint monochromatic LEDs. Color conversion by quantum dots (QDs) can address these issues, but high-performance monochromatic LEDs made using QDs free of restricted, hazardous elements remain to be demonstrated. Here, we show green, amber, and red LEDs formed using InP-based QDs as on-chip color convertor for blue LEDs. Implementing QDs with near-unity photoluminescence efficiency yields a color conversion efficiency over 50% with little intensity roll-off and nearly complete blue light rejection. Moreover, as the conversion efficiency is mostly limited by package losses, we conclude that on-chip color conversion using InP-based QDs can provide spectrum-on-demand LEDs, including monochromatic LEDs that bridge the green gap.

Valorization of phosphor powder of waste fluorescent tubes with an emphasis on the recovery of terbium oxide (Tb4O7)

Waste fluorescent tubes containing yttrium, europium, lanthanum, cerium and terbium are considered important resources of rare earths. Due to the scarcity of terbium in natural deposits, phosphor powder from waste fluorescent tubes could be a potential source of terbium. The presence of terbium with stable aluminates matrix in the phosphor powder makes the terbium recovery challenging. The present paper aims to develop a process to recover high pure terbium oxide (Tb4O7) from phosphor powder of waste fluorescent tubes. In the developed process, leach residue obtained after selective leaching of yttrium and europium was treated for the recovery of terbium. The leach residue was treated by alkali roasting-water leaching to break the aluminates and phosphates matrix. Further, La, Ce, and Tb were recovered by HCl leaching. Terbium from lanthanum and cerium was separated by solvent extraction using D2EHPA as an extractant. Various parameters such as extractant concentration, phase ratio, etc. were optimized for the selective extraction of terbium in the organic phase. The counter-current process was simulated for terbium extraction. High pure terbium oxide (99.8%) was produced from the loaded organic by precipitation stripping followed by calcination. The solid residues and final products were characterized by chemical analysis, XRD and SEM-EDS.