Showing papers by "University of Science and Technology Beijing published in 2014"
TL;DR: The concept of high entropy introduces a new path of developing advanced materials with unique properties, which cannot be achieved by the conventional micro-alloying approach based on only one dominant element as mentioned in this paper.
4,394 citations
TL;DR: A series of six-component (FeCoNiCrMn)100−xAlx (x = 0−20 ǫ) high-entropy alloys was synthesized to investigate the alloying effect of Al on the structure and tensile properties as mentioned in this paper.
954 citations
TL;DR: A way of enhancing the strength of twinning-induced plasticity steel at no ductility trade-off by exploiting the formation of a gradient hierarchical nanotwinned structure during pre-torsion and subsequent tensile deformation.
Abstract: The strength-ductility trade-off has been a long-standing dilemma in materials science. This has limited the potential of many structural materials, steels in particular. Here we report a way of enhancing the strength of twinning-induced plasticity steel at no ductility trade-off. After applying torsion to cylindrical twinning-induced plasticity steel samples to generate a gradient nanotwinned structure along the radial direction, we find that the yielding strength of the material can be doubled at no reduction in ductility. It is shown that this evasion of strength-ductility trade-off is due to the formation of a gradient hierarchical nanotwinned structure during pre-torsion and subsequent tensile deformation. A series of finite element simulations based on crystal plasticity are performed to understand why the gradient twin structure can cause strengthening and ductility retention, and how sequential torsion and tension lead to the observed hierarchical nanotwinned structure through activation of different twinning systems.
722 citations
TL;DR: In this paper, the authors summarized and divided recent intensification technologies of water electrolysis into three categories: external field, new electrolyte composition, and new thermodynamic reaction system.
Abstract: Water electrolysis derived by renewable energy such as solar energy and wind energy is a sustainable method for hydrogen production due to high purity, simple and green process. One of the challenges is to reduce energy consumption of water electrolysis for large-scale application in future. Cell voltage, an important criterion of energy consumption, consists of theoretical decomposition voltage (U-theta), ohmic voltage drop (i*Sigma R) and reaction overpotential (eta). The kinetic and thermodynamic roots of high cell voltage are analyzed systemically in this review. During water electrolysis, bubble coverage on electrode surface and bubble dispersion in electrolyte, namely bubble effect, result in high ohmic voltage drop and large reaction overpotential. Bubble effect is one of the most key factors for high energy consumption. Based on the theoretical analysis, we summarize and divide recent intensification technologies of water electrolysis into three categories: external field, new electrolyte composition and new thermodynamic reaction system. The fundamentals and development of these intensification technologies are discussed and reviewed. Reaction overpotential and ohmic voltage drop are improved kinetically by external field or new electrolyte composition. The thermodynamic decomposition voltage of water is also reduced by new reaction systems such as solid oxide electrolysis cell (SOEC) and carbon assisted water electrolysis (CAWE). (C) 2013 Elsevier Ltd. All rights reserved.
665 citations
TL;DR: An accurate and robust method for detecting texts in natural scene images using a fast and effective pruning algorithm to extract Maximally Stable Extremal Regions (MSERs) as character candidates using the strategy of minimizing regularized variations is proposed.
Abstract: Text detection in natural scene images is an important prerequisite for many content-based image analysis tasks. In this paper, we propose an accurate and robust method for detecting texts in natural scene images. A fast and effective pruning algorithm is designed to extract Maximally Stable Extremal Regions (MSERs) as character candidates using the strategy of minimizing regularized variations. Character candidates are grouped into text candidates by the single-link clustering algorithm, where distance weights and clustering threshold are learned automatically by a novel self-training distance metric learning algorithm. The posterior probabilities of text candidates corresponding to non-text are estimated with a character classifier; text candidates with high non-text probabilities are eliminated and texts are identified with a text classifier. The proposed system is evaluated on the ICDAR 2011 Robust Reading Competition database; the f-measure is over 76%, much better than the state-of-the-art performance of 71%. Experiments on multilingual, street view, multi-orientation and even born-digital databases also demonstrate the effectiveness of the proposed method.
616 citations
TL;DR: In this article, α-Fe2O3 hollow microspheres were synthesized using carbonaceous microsphere sacrificial templates and utilized for high capacity anode materials in lithium ion batteries (LIBs).
Abstract: Multi-shelled α-Fe2O3 hollow microspheres were synthesized using carbonaceous microsphere sacrificial templates and utilized for high capacity anode materials in lithium ion batteries (LIBs). Structural aspects including the shell thickness, number of internal multi-shells, and shell porosity were controlled by synthesis parameters to produce hollow microspheres with maximum lithium capacity and stable cycling behavior. Thin, porous, hollow microspheres with three concentric multi-shells showed the best cycling performance, demonstrating excellent stability and a reversible capacity of up to 1702 mA h g−1 at a current density of 50 mA g−1. The electrode performance is attributed to the large specific surface area and enhanced volumetric capacity of the multi-shelled hollow spheres that provide maximum lithium storage, while the porous thin shells facilitate rapid electrochemical kinetics and buffer mechanical stresses that accompany volume changes during de/lithiation.
601 citations
TL;DR: In this paper, a multilayer graphene/polymer composite films with good mechanical flexibility were fabricated into paraffin-based sandwich structures to evaluate electromagnetic interference (EMI) shielding.
471 citations
TL;DR: It is demonstrated that AgNP-BC could reduce inflammation and promote wound healing, and exhibited significant antibacterial activities with more than 99% reductions in Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa.
396 citations
TL;DR: In this paper, a refractory Hf25Nb25Ti25Zr25 high entropy alloy (HEA) with single body centered cubic (BCC) structure was prepared by copper mold cast method.
390 citations
TL;DR: Uniform multishelled TiO2 hollow microspheres were synthesized for the first time by a simple sacrificial method capable of controlling the shell thickness, intershell spacing, and number of internal multishells, which are used as anodes for lithium ion batteries.
Abstract: Herein, uniform multishelled TiO2 hollow microspheres were synthesized, especially 3- and 4-shelled TiO2 hollow microspheres were synthesized for the first time by a simple sacrificial method capable of controlling the shell thickness, intershell spacing, and number of internal multishells, which are achieved by controlling the size, charge, and diffusion rate of the titanium coordination ions as well as the calcination process. Used as anodes for lithium ion batteries, the multishelled TiO2 hollow microspheres show excellent rate capacity, good cycling performance, and high specific capacity. A superior capacity, up to 237 mAh/g with minimal irreversible capacity after 100 cycles is achieved at a current rate of 1 C (167.5 mA/g), and a capacity of 119 mAh/g is achieved at a current rate of 10 C even after 1200 cycles.
390 citations
TL;DR: In this paper, a two-dimensional (2D) Ti 3 C 2 was synthesized by exfoliation of Ti 3 AlC 2 with HF solution and subsequently intercalation with dimethyl sulfoxide.
TL;DR: In this paper, a multilayer-structured 0-3 nanocomposite was proposed to achieve high energy densities and low dielectric losses in modern electronic and electrical power systems.
Abstract: Dielectric materials with high electric energy densities and low dielectric losses are of critical importance in a number of applications in modern electronic and electrical power systems. An organic–inorganic 0–3 nanocomposite, in which nanoparticles (0-dimensional) are embedded in a 3-dimensionally connected polymer matrix, has the potential to combine the high breakdown strength and low dielectric loss of the polymer with the high dielectric constant of the ceramic fillers, representing a promising approach to realize high energy densities. However, one significant drawback of the composites explored up to now is that the increased dielectric constant of the composites is at the expense of the breakdown strength, limiting the energy density and dielectric reliability. In this study, by expanding the traditional 0–3 nanocomposite approach to a multilayered structure which combines the complementary properties of the constituent layers, one can realize both greater dielectric displacement and a higher breakdown field than that of the polymer matrix. In a typical 3-layer structure, for example, a central nanocomposite layer of higher breakdown strength is introduced to substantially improve the overall breakdown strength of the multilayer-structured composite film, and the outer composite layers filled with large amount of high dielectric constant nanofillers can then be polarized up to higher electric fields, hence enhancing the electric displacement. As a result, the topological-structure modulated nanocomposites, with an optimally tailored nanomorphology and composite structure, yield a discharged energy density of 10 J/cm3 with a dielectric breakdown strength of 450 kV mm–1, much higher than those reported from all earlier studies of nanocomposites.
TL;DR: The effects of elasticity number, slip coefficient, the relaxation time of the heat flux and the Prandtl number on velocity and temperature fields are analyzed and a comparison of Fourier's Law and the Cattaneo–Christov heat flux model is presented.
TL;DR: Wang et al. as discussed by the authors used structural equation modeling (SEM) to examine the direct and indirect relationships among caring climate, job satisfaction, organizational commitment, and job performance of 476 employees working in a Chinese insurance company.
Abstract: This research uses structural equation modeling (SEM) to examine the direct and indirect relationships among caring climate, job satisfaction, organizational commitment, and job performance of 476 employees working in a Chinese insurance company. The SEM result showed that caring climate had a significant direct impact on job satisfaction, organizational command, and job performance. Caring climate also had a significant indirect impact on organizational commitment through the mediating role of job satisfaction, and on job performance through the mediating role of job satisfaction and organizational commitment. In addition, job satisfaction had significant direct impact on organizational commitment, through which it also had a significant indirect impact on job performance. Finally, organizational commitment had a significant direct impact on job performance.
TL;DR: At atomic-scale images, it is demonstrated directly that the evolution of the misorientation angle between neighbouring grains can be quantitatively accounted for by the change of the Frank–Bilby dislocation content in the grain boundary.
Abstract: Grain rotation is a well-known phenomenon during high (homologous) temperature deformation and recrystallization of polycrystalline materials. In recent years, grain rotation has also been proposed as a plasticity mechanism at low temperatures (for example, room temperature for metals), especially for nanocrystalline grains with diameter d less than ~15 nm. Here, in tensile-loaded Pt thin films under a high-resolution transmission electron microscope, we show that the plasticity mechanism transitions from cross-grain dislocation glide in larger grains (d>6 nm) to a mode of coordinated rotation of multiple grains for grains with d<6 nm. The mechanism underlying the grain rotation is dislocation climb at the grain boundary, rather than grain boundary sliding or diffusional creep. Our atomic-scale images demonstrate directly that the evolution of the misorientation angle between neighbouring grains can be quantitatively accounted for by the change of the Frank–Bilby dislocation content in the grain boundary. Grain rotation is proposed as an active deformation mechanism in nanocrystalline metals at room temperature. Here, during in-situatomic scale experimentation, the authors observe that grains with a size <6 nm deform by coordinated rotation of multiple grains, associated with dislocation climb at grain boundaries.
TL;DR: Large-area dual-scaled porous nitrocellulose membranes are fabricated by a facile, inexpensive and scalable perforating approach and show stable superhydrophilicity in air and underwater superoleophobicity.
Abstract: Large-area dual-scaled porous nitrocellulose (p-NC) membranes are fabricated by a facile, inexpensive and scalable perforating approach. These p-NC membranes show stable superhydrophilicity in air and underwater superoleophobicity. The p-NC membranes with intrinsic nanopores and array of microscale perforated pores could selectively and efficiently separate water from various oil/water mixtures with high efficiency (>99%) rapidly.
TL;DR: The high risks in this study highlight the attention paid to the health of children who live in the vicinity of coking activities and the importance of site-specific multi-pathway health risk assessments and food safety to protect potentially exposed children.
TL;DR: In this article, the electronic properties of the benzo[a]pyrene diol epoxide enantiomers, along with a detailed analysis of the energy landscape, geometry, and electronic configuration of the epoxide ring, were analyzed.
Abstract: Benzo[a]pyrene is a known carcinogen, which derives from fossil fuel combustion, cigarette smoke, and generic biomass combustion including traffic emissions. This potent carcinogen has a well-known mechanism of action, leading to the formation of adducts with the DNA, primarily at guanosine positions. The reactivity and chemistry of this notorious compound are, however, dependent on the electronic configuration of the biologically activated metabolite, the benzo[a]pyrene diol epoxide. The activated metabolite exists mainly as four isomers, which have particular chemical reactivities toward guanosine sites on the DNA. These isomers exert also a different carcinogenicity compared to one another, which is a feature that is conventionally attributed to their geometry. However, the reactivity and properties of the isomers are not fully defined, and a determination of these properties by wavefunction behavior is required. This study reports the electronic properties of the benzo[a]pyrene diol epoxide enantiomers, along with a detailed analysis of the energy landscape, geometry, and electronic configuration of the epoxide ring. The results show that the epoxide ring, the core of the reactivity, bears different properties at the level of wavefunction for each isomer. Each of the isomers has a distinct profile on the epoxide ring, in terms of hydrogen bonds and in terms of the non-covalent interaction between the diol groups and the epoxide. These profiles generate differential reactivities of epoxide group, which can be attributed to its local bond lengths, the electron localization function, and polarized bonds. Most interestingly, the quantum chemical calculations showed also that the epoxide ring is inclined more perpendicularly toward the angular ring plane for the more carcinogenic isomers, a feature which suggests a potential geometrical relationship between the inclination of the epoxide group and its interaction with the guanosine group upon adduct formation. Our results introduce novel and crucial information, which assist in understanding the mechanism of toxic potential of this known molecule, and display the strength and level of detail of applying quantum chemical methods to reveal the reactivity, energy properties, and electronic properties of a mutagen.
TL;DR: In this paper, a highly ordered porous carbon (HOPC) was used as an effective electromagnetic absorber for microwave-absorbing materials, and the porous structure allowed HOPC to possess high surface area and establish effective three-dimensional conductive interconnections at very low filler loading, which is responsible for effective electrical loss in terms of dissipating the induced current in corresponding wax composites.
TL;DR: SnO2 hollow microspheres that are utilized as a scattering layer on top of P25 films increase the DSSC photoconversion efficiency from 7.29% to 9.53% due to enhanced light scattering.
Abstract: Quintuple-shelled SnO2 hollow microspheres are prepared by a hard-template method. DSSCs constructed with SnO2 multi-shell photoanodes show a record photoconversion efficiency of 7.18% due to enhanced light scattering. SnO2 hollow microspheres that are utilized as a scattering layer on top of P25 films increase the DSSC photoconversion efficiency from 7.29% to 9.53%.
TL;DR: In this paper, the steady state flow behavior of the FeCoNiCrMn high-entropy alloy at temperatures ranging from 1023 to 1123 K was systematically characterized, and it was found that the stress exponent (i.e., the reciprocal of strain-rate sensitivity) was dependent on the applied strain rate.
TL;DR: The unique properties of the triple-shelled CeO₂ hollow microspheres including more efficient multiple reflections of the incident light by the inner shells, the larger surface area and more active sites for improving separation of electron-hole pairs, and the more curved surfaces unfavorable for deposition of in situ generated Ag nanoparticles are attributed.
Abstract: A general self-templating method is introduced to construct triple-shelled CeO2 hollow microspheres, which are composed of tiny CeO2 nanoparticles. When the triple-shelled CeO2 hollow microspheres are used as photocatalysts for direct water oxidation with AgNO3 as the electron scavenger, excellent activity and enhanced stability for O2 evolution are achieved, in contrast with commercial CeO2 nanoparticles, single-shelled CeO2 hollow microspheres and double-shelled CeO2 hollow microspheres. Such an outstanding performance is attributed to the unique properties of the triple-shelled CeO2 hollow microspheres including more efficient multiple reflections of the incident light by the inner shells, the larger surface area and more active sites for improving separation of electron–hole pairs, and the more curved surfaces unfavorable for deposition of in situ generated Ag nanoparticles.
TL;DR: In this paper, three conjugated polymers based on BDT and thieno[3,4-b]thiophene units with furan, thiophene and selenophene as side groups were synthesized and applied in polymer solar cells.
Abstract: Recently, the benzodithiophene- (BDT-) based polymers with conjugated side groups attracted considerable attention due to their superior properties in polymer solar cells (PSCs), so the investigation of the side chain effects on the photovoltaic properties of this type of polymers is an interesting and important topic for molecular design. Herein, three conjugated polymers based on BDT and thieno[3,4-b]thiophene units with furan, thiophene and selenophene as side groups, named as PBDTTT-EFF, PBDTTT-EFT, and PBDTTT-EFS, were synthesized and applied in polymer solar cells. The polymers were characterized in parallel by absorption spectroscopy, thermogravimetric analysis (TGA), density functional theory (DFT), ultraviolet photoemission spectroscopy (UPS), X-ray diffraction (XRD), and photovoltaic measurements. The results show that the dihedral angles between the BDT and conjugated side groups play important roles in affecting the absorption bands, HOMO levels, crystallinities, and aggregation sizes of the p...
TL;DR: This paper surveys different aspects of bio-inspired mechanisms and examines various algorithms that have been applied to artificial SON systems and discusses advantages, drawbacks, and further design challenges of variant algorithms.
Abstract: Inspired by swarm intelligence observed in social species, the artificial self-organized networking (SON) systems are expected to exhibit some intelligent features (e.g., flexibility, robustness, decentralized control, and self-evolution, etc.) that may have made social species so successful in the biosphere. Self-organized networks with swarm intelligence as one possible solution have attracted a lot of attention from both academia and industry. In this paper, we survey different aspects of bio-inspired mechanisms and examine various algorithms that have been applied to artificial SON systems. The existing well-known bio-inspired algorithms such as pulse-coupled oscillators (PCO)-based synchronization, ant- and/or bee-inspired cooperation and division of labor, immune systems inspired network security and Ant Colony Optimization (ACO)-based multipath routing have been surveyed and compared. The main contributions of this survey include 1) providing principles and optimization approaches of variant bio-inspired algorithms, 2) surveying and comparing critical SON issues from the perspective of physical-layer, Media Access Control (MAC)-layer and network-layer operations, and 3) discussing advantages, drawbacks, and further design challenges of variant algorithms, and then identifying their new directions and applications. In consideration of the development trends of communications networks (e.g., large-scale, heterogeneity, spectrum scarcity, etc.), some open research issues, including SON designing tradeoffs, Self-X capabilities in the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE)/LTE-Advanced systems, cognitive machine-to-machine (M2M) self-optimization, cross-layer design, resource scheduling, and power control, etc., are also discussed in this survey.
TL;DR: In this article, the use of GNPs to strengthen the bulk Cu-matrix composites was reported, and the GNP reinforced composites were prepared by a combination of the ball milling and hot-pressing processing, and their mechanical properties were investigated.
Abstract: Graphene nanoplatelets (GNPs) exhibit ultra-high strength and elastic modulus. Therefore, they are potential ideal reinforcements in metal–matrix composites (MMCs). In this work, we report the use of GNPs to strengthen the bulk Cu-matrix composites. GNP reinforced Cu-matrix (GNP/Cu) composites were prepared by a combination of the ball milling and hot-pressing processing, and their mechanical properties were investigated. Microstructure studies indicated that the GNPs with 0–8 vol.% contents were well dispersed in the Cu matrix by ball milling. Compared to unreinforced Cu, the GNP/Cu composites showed a remarkable increase in yield strength and Young's modulus up to 114 and 37% at 8 vol.% GNP content, respectively. The extraordinary reinforcement is attributed to the homogeneous dispersion of GNPs and grain refinement. However, the mechanical improvement of GNP/Cu composites was still below the theoretical value. The possible reasons for this deviation were discussed and the methods for further mechanical improvement of GNP/Cu composites were proposed.
TL;DR: A white LED device which is obtained by combining a 370 nm UV chip with commercial blue phosphor and the present yellow phosphor has been fabricated and exhibit good application properties.
Abstract: New compound discovery is of interest in the field of inorganic solid-state chemistry. In this work, a whitlockite-type structure Sr1.75Ca1.25(PO4)2 newly found by composition design in the Sr3(PO4)2–Ca3(PO4)2 join was reported. Crystal structure and luminescence properties of Sr1.75Ca1.25(PO4)2:Eu2+ were investigated, and the yellow-emitting phosphor was further employed in fabricating near-ultraviolet-pumped white light-emitting diodes (w-LEDs). The structure and crystallographic site occupancy of Eu2+ in the host were identified via X-ray powder diffraction refinement using Rietveld method. The Sr1.75Ca1.25(PO4)2:Eu2+ phosphors absorb in the UV–vis spectral region of 250–430 nm and exhibit an intense asymmetric broadband emission peaking at 518 nm under λex = 365 nm which is ascribed to the 5d–4f allowed transition of Eu2+. The luminescence properties and mechanism are also investigated as a function of Eu2+ concentration. A white LED device which is obtained by combining a 370 nm UV chip with commerci...
TL;DR: The research established that transformational leadership positively influences IWB, which includes idea generation as well as idea implementation, which was stronger among employees with a higher interdependent self-construal and a lower independent self- construal.
Abstract: Purpose – The purpose of this paper is to explore the mediating role of psychological empowerment and the moderating role of self-construal (independent and interdependent) on the relationship between transformational leadership and employees’ innovative work behavior (IWB). Design/methodology/approach – A total of 639 followers and 87 leaders filled out questionnaires from cross-industry sample of five most innovative companies of China. Structural equation modeling was used to analyze the relations. Findings – Results revealed that psychological empowerment mediated the relationship between transformational leadership and IWB. The research established that transformational leadership positively influences IWB which includes idea generation as well as idea implementation. The results also showed that the relationship between transformational leadership and IWB was stronger among employees with a higher interdependent self-construal and a lower independent self-construal. Originality/value – This study ad...
TL;DR: In this article, the authors proposed some guidelines in predicting phase formation, using thermodynamic and topological parameters of the constituent elements, which can pave the way toward the composition design of MEAs and HEAs, as well as property optimization based on the composition-structure-property relationship.
Abstract: With multiple elements mixed at equal or near-equal molar ratios, the emerging, high-entropy alloys (HEAs), also named multi-principal elements alloys (MEAs), have posed tremendous challenges to materials scientists and physicists, e.g., how to predict high-entropy phase formation and design alloys. In this paper, we propose some guidelines in predicting phase formation, using thermodynamic and topological parameters of the constituent elements. This guideline together with the existing ones will pave the way toward the composition design of MEAs and HEAs, as well as property optimization based on the composition–structure–property relationship.
TL;DR: A new predictor called “iNitro-Tyr” was developed by incorporating the position-specific dipeptide propensity into the general pseudo amino acid composition for discriminating the nitrotyrosine sites from non-nitrotyosine sites in proteins, and it was demonstrated via the rigorous jackknife tests that the new predictor can yield higher success rate but also is much more stable and less noisy.
Abstract: Nitrotyrosine is one of the post-translational modifications (PTMs) in proteins that occurs when their tyrosine residue is nitrated. Compared with healthy people, a remarkably increased level of nitrotyrosine is detected in those suffering from rheumatoid arthritis, septic shock, and coeliac disease. Given an uncharacterized protein sequence that contains many tyrosine residues, which one of them can be nitrated and which one cannot? This is a challenging problem, not only directly related to in-depth understanding the PTM's mechanism but also to the nitrotyrosine-based drug development. Particularly, with the avalanche of protein sequences generated in the postgenomic age, it is highly desired to develop a high throughput tool in this regard. Here, a new predictor called "iNitro-Tyr" was developed by incorporating the position-specific dipeptide propensity into the general pseudo amino acid composition for discriminating the nitrotyrosine sites from non-nitrotyrosine sites in proteins. It was demonstrated via the rigorous jackknife tests that the new predictor not only can yield higher success rate but also is much more stable and less noisy. A web-server for iNitro-Tyr is accessible to the public at http://app.aporc.org/iNitro-Tyr/. For the convenience of most experimental scientists, we have further provided a protocol of step-by-step guide, by which users can easily get their desired results without the need to follow the complicated mathematics that were presented in this paper just for the integrity of its development process. It has not escaped our notice that the approach presented here can be also used to deal with the other PTM sites in proteins.
TL;DR: A detailed analysis of the structural properties indicates the formation of isostructural scheelite-type CsGd1-xEux(MoO4)2 solid-solutions over the composition range of 0 ≤ x ≤ 1, revealing great potential for applications in white light-emitting diode devices.
Abstract: Scheelite related alkali-metal rare-earth double molybdate compounds with a general formula of ALn(MoO4)2 can find wide application as red phosphors. The crystal chemistry and luminescence properties of red-emitting CsGd1−xEux(MoO4)2 solid-solution phosphors have been evaluated in the present paper. A detailed analysis of the structural properties indicates the formation of isostructural scheelite-type CsGd1−xEux(MoO4)2 solid-solutions over the composition range of 0 ≤ x ≤ 1. The photoluminescence emission (PL) and excitation (PLE) spectra, and the decay curves were measured for this series of compounds. The critical doping concentration of Eu3+ is determined to be x = 0.6 in order to realize the maximum emission intensity. The emission spectra of the as-obtained CsGd(1−x)Eux(MoO4)2 phosphors show narrow high intensity red lines at 592 and 615 nm upon excitation at 394 or 465 nm, revealing great potential for applications in white light-emitting diode devices.