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Rationalizing the underlying mechanism that correlates phonon transport with structural complexity is crucial for the development of materials with ultralow thermal conductivity. Herein, we investigated the abnormal thermal transport and lattice dynamics in Ag9FeS6-xTex argyrodite-type compounds via a combination of properties characterization, model analysis, and theoretical calculations. Our results show that the ordered α-phase and disordered β-phase of Ag9FeS6-xTex exhibit distinct temperature dependency of lattice thermal conductivity κL. Specifically, the κL of ordered α-phase shows a crystalline characteristic with a pronounced Umklapp peak observed at ∼10 K, while the κL of disordered β-phase monotonously increases in the whole temperature range without a peak or plateau. Such different thermal transport behavior is a result of different contributions to the reduction of κL from the structural disorder and the low-lying multi-Einstein oscillators, both of which are associated with the weakly bonded Ag+ ions. The knowledge depicted here provides fundamental insights into the extraordinary thermal transports in materials with structural disorder and/or weak chemical bonds.

Recently, many novel superionic thermoelectric materials have been discovered along the concept of “phonon-liquid electron-crystal” (PLEC). Among them, Cu 2- x Se-based liquid-like materials are typical examples. In this study, a series of copper-deficient Cu 2- x Se (0.05 ≤ x ≤ 0.25) materials were synthesized and used to study the role of Cu vacancies on the electrical and thermal transport properties. The X-ray photoelectron spectroscopy (XPS) measurements suggest that the valence states of Cu and Se are independent on the Cu/Se atomic ratio. With increasing the content of Cu vacancies, the hole concentration is monotonously increased, leading to the improved electrical conductivity and reduced Seebeck coefficient. Based on the single parabolic band model analysis, it is found that changing the content of Cu vacancies does not obviously modify the material's electronic band structure and effective mass. Due to the presence of highly mobile Cu ions inside the crystal structure, the lattice thermal conductivities of all Cu 2- x Se (0.05 ≤ x ≤ 0.25) materials are very low with values around 0.39 W m −1 K −1 at 500 K. Because of the significantly reduced Seebeck coefficient and increased electronic thermal conductivity, the thermoelectric figure of merit zTs are decreased when increasing x from 0.05 to 0.25. At 750 K, a maximum zT of 0.46 is obtained in Cu 1.95 Se among all Cu 2- x Se (0.05 ≤ x ≤ 0.25) materials.

The crystal structure uniquely imparts the specific properties of a material, and thus provides the starting point for any quantitative understanding of thermoelectric properties. Cu2−xSe is an intensely studied high performing, non-toxic and cheap thermoelectric material, and here for the first time, the average structure of β-Cu2−xSe is reported based on analysis of multi-temperature single-crystal X-ray diffraction data. It consists of Se–Cu layers with additional copper between every alternate layer. The structural changes during the peculiarzTenhancing phase transition mainly consist of changes in the inter-layer distance coupled with subtle Cu migration. Just prior to the transition the structure exhibits strong negative thermal expansion due to the reordering of Cu atoms, when approached from low temperatures. The phase transition is fully reversible and group–subgroup symmetry relations are derived that relate the low-temperature β-phase to the high-temperature α-phase. Weak superstructure reflections are observed and a possible Cu ordering is proposed. The structural rearrangement may have a significant impact on the band structure and the Cu rearrangement may also be linked to an entropy increase. Both factors potentially contribute to the extraordinaryzTenhancement across the phase transition.

The biomass thermoplastic composites were prepared by extrusion molding method with poplar flour, rice husk, cotton stalk and corn stalk. The thermo gravimetric analyzer (TGA) has also been used for evaluating the pyrolysis process of the composites. The results showed that the pyrolysis process mainly consists of two stages: biomass pyrolysis and the plastic pyrolysis. The increase of biomass content in the composite raised the first stage pyrolysis peak temperature. However, the carbon residue was reduced and the pyrolysis efficiency was better because of synergistic effect of biomass and plastic. The composite with different kinds of biomass have similar pyrolysis process, and the pyrolysis efficiency of the composite with corn stalk was best. The calcium carbonate could inhibit pyrolysis process and increase the first stage pyrolysis peak temperature and carbon residue as a filling material of the composite. Keywords: Biomass thermoplastic composite, Calcium carbonate, Pyrolysis characteristic

The biomass polyethylene composites filled with poplar wood flour, rice husk, cotton stalk or corn stalk were prepared by extrusion molding. The static viscoelasticity of composites was investigated by the dynamic thermal mechanical analyzer (DMA). Through the stress-strain scanning, it is found that the linear viscoelasticity interval of composites gradually decreases as the temperature rises, and the critical stress and strain values are 0.8 MPa and 0.03% respectively. The experiment shows that as the temperature rises, the creep compliance of biomass polyethylene composites is increased; under the constant temperature, the creep compliance decreases with the increase of content of biomass and calcium carbonate. The biomass and calcium carbonate used to prepare composites as filler can improve damping vibration attenuation and reduce stress deformation of composites. The stress relaxation modulus of composites is reduced and the relaxation rate increases at the higher temperature. The biomass and calcium carbonate used to prepare composites as filler not only can reduce costs, but also can increase stress relaxation modulus and improve the size thermostability of composites. The corn stalk is a good kind of biomass raw material for composites since it can improve the creep resistance property and the stress relaxation resistance property of composites more effectively than other three kinds of biomass (poplar wood flour, rice husk and cotton stalk). Keywords: Biomass, Composites, Calcium carbonate, Static viscoelasticity, Creep, Stress relaxation

We report a ternary argyrodite-type Ag9GaSe6 compound as a promising thermoelectric material in a moderate temperature range. Due to high carrier mobility and ultralow lattice thermal conductivity, a maximum ZT of 1.1 was obtained with stoichiometric Ag9GaSe6 at 800 K. Via introducing slight Se-deficiency to optimize the carrier concentration, the maximum ZT is further enhanced to 1.3.

Liquid‐like materials are one family of promising thermoelectric materials discovered in the past years due to their advantanges of ultrahigh thermoelectric figure of merit (zT), low cost, and environmental friendliness. However, their practial applications are greatly limited by the low service stability from the Cu/Ag metal deposition under large current and/or temperature gradient. Both high zT for high efficiency and large critical voltage for good stability are required for liquid‐like materials, but they are usually strongly correlated and hard to be tuned individually. Herein, based on the thermodynamic analysis, it is shown that such a correlation can be decoupled through doping immobile ions into the liquid‐like sublattice. Taking Cu2− δS as an example, doping immobile Fe ions in Cu1.90S scarcely degrades the initial large critical voltage, but significantly enhances the zT to 1.5 at 1000 K by tuning the carrier concentration to the optimal range. Combining the low‐cost and environmentally friendly features, these Fe‐doped Cu2− δS‐based compounds show great potential in civil applications. This study sheds light on the realization of both good stability and high performance for many other liquid‐like thermoelectric materials that have not been considered for real applications before., Herein, the correlation between thermoelectric figure of merit and critical voltage is revealed and the thermodynamic analysis suggests that it can be decoupled through doping immobile ions into the liquid‐like sublattice. Along this direction, a new approach to design and fabricate liquid‐like materials with both high thermoelectric performance and good stability is proposed and well demonstrated in Cu2− δS‐based liquid‐like materials.

Most of the state-of-the-art thermoelectric (TE) materials exhibit high crystal symmetry, multiple valleys near the Fermi level, heavy constituent elements with small electronegativity differences, or complex crystal structure. Typically, such general features have been well observed in those well-known TE materials such as Bi

Ag

Liquid-like binary Cu

Ag2Se and CuAgSe have been recently reported as promising thermoelectric materials at room temperature. The traditional melting–annealing–sintering processes are used to grow Ag2Se and CuAgSe materials with the disadvantages of high costs of energy and time. In this work, phase-pure polycrystalline Ag2Se and CuAgSe compounds were synthesized from raw elemental powders directly by manual mixing followed by spark plasma sintering (MM-SPS) in a few minutes. The influence of SPS heating rate on the phase composition, microstructure, and thermoelectric properties, including Seebeck coefficient, electrical conductivity, and thermal conductivity, were investigated. The zTs of 0.8 at 390 K and 0.6 at 450 K are obtained for Ag2Se and CuAgSe, respectively, which is comparable with the values in the materials prepared by the traditional method. Furthermore, this ultrafast sample synthesis can significantly save material synthesis time and thus has the obvious advantage for large-scale production.

Discovering new high-performance thermoelectric (TE) materials is an eternal pursuit in TE community. Searching materials with heavy average atomic mass to realize intrinsically low lattice thermal conductivity is an effective strategy to discover novel promising TE materials. In this article, by using high-throughput screening, Cu3ErTe3 with heavy average atomic mass is screened out of the 27,782 entries with band gaps in the Materials Informatics Platform as a potential high-performance TE material. In experiment, a series of phase pure Cu3ErTe3-based samples are synthesized. Being consistent with the predication, Cu3ErTe3 has a low speed of sound of 2151 m s−1 and an intrinsically low lattice thermal conductivity of 1.2 W m−1 K−1 at 300 K. Meanwhile, the moderate band gap of Cu3ErTe3 enables decent electrical transport properties. Finally, a peak figure of merit around unit at 900 K is achieved for Ag-alloyed Cu3ErTe3. Beyond the present Cu3LnTe3 (Ln = rare earth metal) compounds, other compounds predicated by the high-throughput screening, such as Cu3La3Bi4, Cu3Ln7Te12 (Ln = Tb, Dy, Ho, and Er), Cu2HfTe3, and Cu3Nd3Sb4, might also possess excellent TE performance. This work opens a door to a large family of new potential high-performance TE materials that have not been investigated for TEs.

With increasing degree of power electronics in power system, the interaction between controllers of different FACTS devices poses a greater threat to security and stability of the system. In this paper, a linearized state space model with SVC and STATCOM was established, and the negative interaction mechanism of FACTS device in transient process was analyzed and summarized considering control characteristics, operation mode and setting principle of PI controllers. A model predictive control (MPC) is proposed to replace traditional PI link to establish a coordination controller to overcome the difficulties of PI control parameter setting and global optimization.

Dual CPU redundant operation of PLC is of great significance to the reliability of industrial automation control system. In view of the problems existing in the traditional dual CPU PLC redundancy control mode based on hardware strategy, this paper proposes a dual CPU redundancy control idea based on software strategy, and describes in detail the specific scheme of Dual CPU redundancy software design using A-B ControlLogix series PLC.

Thermal conductivity is a very basic property that determines how fast a material conducts heat, which plays an important and sometimes a dominant role in many fields. However, because materials with phase transitions have been widely used recently, understanding and measuring temperature-dependent thermal conductivity during phase transitions are important and sometimes even questionable. Here, the thermal transport equation is corrected by including heat absorption due to phase transitions to reveal how a phase transition affects the measured thermal conductivity. In addition to the enhanced heat capacity that is well known, it is found that thermal diffusivity can be abnormally lowered from the true value, which is also dependent on the speed of phase transitions. The extraction of the true thermal conductivity requires removing the contributions from both altered heat capacity and thermal diffusivity during phase transitions, which is well demonstrated in four selected kinds of phase transition materials (Cu2 Se, Cu2 S, Ag2 S, and Ag2 Se) in experiment. This study also explains the lowered abnormal thermal diffusivity during phase transitions in other materials and thus provides a novel strategy to engineer thermal conductivity for various applications.

Phase transition is a fundamental physical phenomenon that has been widely studied both theoretically and experimentally. According to the Landau theory, the coexistence of high- and low-temperature phases is thermodynamically impossible during a second-order phase transition in a bulk single crystal. Here, the coexistence of two (α and β) phases in wedge-shaped nanosized single-crystal Cu

A novel quaternary Cu

Binary Cu2Se and Cu2Te have gained great attention recently because of their interesting and abnormal physical properties, such as ultralow thermal conductivity, high carrier mobility, large effective mass of carriers and excellent thermoelectric performance. In this study, we find that these two compounds are completely miscible throughout the studied composition range. The trigonal structure of Cu2Se is maintained when the Te content x is 0.2, but a new trigonal structure is formed when the Te content x is between 0.3 and 0.7. The carrier concentration is greatly improved when increasing the Te content in Cu2Se1-xTex solid solutions, resulting in a much reduced electrical resistivity and Seebeck coefficient in the whole temperature range as compared with those of binary Cu2Se. The total thermal conductivity is inversely increased due to the contribution from enhanced carrier thermal conductivity. As a result, the overall thermoelectric performance of Cu2Se1-xTex solid solutions lies between Cu2Se and Cu2Te. We also find that the quality factor of Cu2Se1-xTex is higher than those of most typical thermoelectric materials. Thus the thermoelectric performance can be further improved if the intrinsically high hole carrier concentrations can be reduced in Cu2Se1-xTex.

Distributed temperature sensing (DTS) provides an important technology support for the earth-rock junctions of dike projects (ERJD), which are binding sites between culvert, gates, and pipes and dike body and dike foundation. In this study, a blind source separation model is used for the identification of leakages based on the temperature data of DTS in leakage monitoring of ERJD. First, a denoising method is established based on the temperature monitoring data of distributed optical fiber in ERJD by a wavelet packet signal decomposition technique. The temperature monitoring messages of fibers are combined response for leakages and other factors. Its character of unclear responding mechanism is very obvious. Thus, a blind source separation technology is finally selected. Then, the rule of temperature measurement data for optical fiber is analyzed and its temporal and spatial change process is also discussed. The realization method of the blind source separation model is explored by combining independent component analysis (ICA) with principal component analysis (PCA). The practical test result in an example shows that the method could efficiently locate and identify the leakage location of ERJD. This paper is expected to be useful for further scientific research and efficient applications of distributed optical fiber sensing technology.

Cuprous selenide (Cu2Se) has recently shown a very high dimensionless thermoelectric figure of merit zT as well as a dramatic increase in thermoelectric performance during the critical second-order phase transition. The present study indicates that the ultrahigh thermoelectric performance arises from its specific structural features involving multiformity of Cu ordering and drastic structural fluctuation during phase transition. The Cu2Se sample consists of domains of different ordered lamellar structures of Cu atoms which are coherently immersed in the long-range ordered Se pseudo-fcc framework. The specific self-independent binary-sublattice structures have been found to enhance phonon scattering while still guaranteeing good carrier mobilities. Upon increasing the temperature to near phase transition, the multiple structures undergo intense and stepwise changes including appearance of new ordered structures for copper, disordering and diffusion of Cu atoms across the interlayers, and finally random distribution of Cu in the Se cubic sublattice which alters a little during the phase transition. Such extreme structural fluctuation results in critical electron and phonon scatterings that expedite an exceptional enhancement of thermoelectric performance.

We report a ternary argyrodite-type Ag

High-throughput explorations of novel thermoelectric materials based on the Materials Genome Initiative paradigm only focus on digging into the structure-property space using nonglobal indicators to design materials with tunable electrical and thermal transport properties. As the genomic units, following the biogene tradition, such indicators include localized crystal structural blocks in real space or band degeneracy at certain points in reciprocal space. However, this nonglobal approach does not consider how real materials differentiate from others. Here, this study successfully develops a strategy of using entropy as the global gene-like performance indicator that shows how multicomponent thermoelectric materials with high entropy can be designed via a high-throughput screening method. Optimizing entropy works as an effective guide to greatly improve the thermoelectric performance through either a significantly depressed lattice thermal conductivity down to its theoretical minimum value and/or via enhancing the crystal structure symmetry to yield large Seebeck coefficients. The entropy engineering using multicomponent crystal structures or other possible techniques provides a new avenue for an improvement of the thermoelectric performance beyond the current methods and approaches.

Liquid-like thermoelectric materials have recently received heightened attentions due to their exceptional thermal and electrical transport properties. As a typical example, Cu2−ySe has good electrical transport properties while Cu2−yS has extremely low lattice thermal conductivity. Combining these stirring characters into one material is expected to result in excellent thermoelectric performance. In this study, we found that Cu2−ySe and Cu2−yS can form a solid solution in the composition range down to half Se and half S. XRD, SEM and TEM reveal that Cu2−ySe0.5S0.5 possesses a unique hierarchical microstructure composed of mesoscale polymorphs, nanoscale domains and modulations. Besides, the liquid-like copper ions at high temperature not only strongly scatter lattice phonons but also eliminate some of the transverse phonon vibrations. Combining with the extraordinarily low sound speeds, an overall ultralow thermal conductivity is achieved in Cu2−ySe0.5S0.5 with the values similar to that in Cu2S. Furthermore, the electrical transport performance of Cu2−ySe0.5S0.5 is significantly improved through tuning its native Cu vacancies. High electrical power factors similar to or even superior to Cu2−ySe are observed due to the high weighted mobility. All these favorable factors lead to much enhanced quality factor and thus remarkably high thermoelectric performance in Cu2−ySe0.5S0.5, which reaches a ZT of 2.3 at 1000 K, among the highest values in bulk materials. This is a submitted manuscript of an article published by Elsevier Ltd in Materials Today Physics, 7 June 2017.

Thermoelectric materials require an optimal carrier concentration to maximize electrical transport and thus thermoelectric performance. Element doping and composition off-stoichiometry are the two general and effective approaches for optimizing carrier concentrations, which have been successfully applied in almost all semiconductors. In this study, we propose a new strategy called bonding energy variation to tune the carrier concentrations in Cu2Se-based liquid-like thermoelectric compounds. By utilizing the different bond features in Cu2Se and Cu2S, alloying S at the Se sites successfully increases the bonding energy to fix Cu atoms in the crystal lattice to suppress the formation of Cu vacancies, leading to greatly reduced carrier concentrations toward the optimal value. Via a combination of the lowered electrical and lattice thermal conductivities and the relatively good carrier mobility caused by the weak alloy scattering potential, ultrahigh zT values are achieved in slightly S-doped Cu2Se with a maximal value of 2.0 at 1000 K, 30% higher than that in nominally stoichiometric Cu2Se. © American Chemical Society 2017. This is the authors accepted and refereed manuscript to the article. Locked until 24.7.2018 due to copyright restrictions.

Most of the state-of-the-art thermoelectric (TE) materials exhibit high crystal symmetry, multiple valleys near the Fermi level, heavy constituent elements with small electronegativity differences, or complex crystal structure. Typically, such general features have been well observed in those well-known TE materials such as Bi2 X3 -, SnX-, and PbX-based compounds (X = S, Se, and Te). The performance is usually high in the materials with heavy constituent elements such as Te and Se, but it is low for light constituent elements such as S. However, there is a great abnormality in Cu2 X-based compounds in which Cu2 Te has much lower TE figure of merit (zT) than Cu2 S and Cu2 Se. It is demonstrated that the Cu2 Te-based compounds are also excellent TE materials if Cu deficiency is sufficiently suppressed. By introducing Ag2 Te into Cu2 Te, the carrier concentration is substantially reduced to significantly improve the zT with a record-high value of 1.8, 323% improvement over Cu2 Te and outperforms any other Cu2 Te-based materials. The single parabolic band model is used to further prove that all Cu2 X-based compounds are excellent TE materials. Such finding makes Cu2 X-based compounds the only type of material composed of three sequent main group elements that all possess very high zT s above 1.5.

Pseudo-binary GeSbTe alloys, best known as phase-change materials, are quasi-two-dimensional semiconductors in their stable trigonal phases with high electrical conductivity and low thermal conductivity, but their thermoelectric properties have not been systematically investigated. Here, in this letter, we prepared polycrystalline Ge2Sb2Te5, GeSb2Te4, and GeSb4Te7 bulk materials and studied the thermoelectric transport properties. Large anisotropy in Seebeck coefficient as well as in electrical conductivity is observed, which is not commonly reported in polycrystalline thermoelectric materials. Combining experimental study and theoretical calculations, one can find that this phenomenon is attributed to the asymmetry of a material's band structure. Maximal zT values of 0.46–0.60 are achieved at 750 K, indicating that GeSbTe-based compounds are promising thermoelectric materials for mid-temperature applications.

The average structure of β-Cu2−xSe is reported based on analysis of multi-temperature single-crystal X-ray diffraction data, and structural changes, including a large negative thermal expansion, across the β to α phase transition are discussed. The structural model also describes well high-resolution synchrotron powder X-ray diffraction data., The crystal structure uniquely imparts the specific properties of a material, and thus provides the starting point for any quantitative understanding of thermoelectric properties. Cu2−xSe is an intensely studied high performing, non-toxic and cheap thermoelectric material, and here for the first time, the average structure of β-Cu2−xSe is reported based on analysis of multi-temperature single-crystal X-ray diffraction data. It consists of Se–Cu layers with additional copper between every alternate layer. The structural changes during the peculiar zT enhancing phase transition mainly consist of changes in the inter-layer distance coupled with subtle Cu migration. Just prior to the transition the structure exhibits strong negative thermal expansion due to the reordering of Cu atoms, when approached from low temperatures. The phase transition is fully reversible and group–subgroup symmetry relations are derived that relate the low-temperature β-phase to the high-temperature α-phase. Weak superstructure reflections are observed and a possible Cu ordering is proposed. The structural rearrangement may have a significant impact on the band structure and the Cu rearrangement may also be linked to an entropy increase. Both factors potentially contribute to the extraordinary zT enhancement across the phase transition.

Human tumor necrosis factor related apoptosis inducing ligand (TRAIL) can selectively induce apoptosis in a variety of transformed cells and is currently being developed as a cancer therapeutic drug. Here we expressed the TRAIL protein including extracellular (114-281aa) without any tag protein named TRAIL-NT, and prepared anti-TRAIL polyclonal antibodies (Poly-Ab). The human TRAIL extracellular gene was amplified from PBMC and cloned into pGEM-T-Easy vector for sequence analysis. The expression vector pET-28a/TRAIL was constructed using the DNA recombinant method, and the recombinant protein without any tag protein was expressed in Escherichia coli BL21(DE3). The TRAIL-NT protein was purified by cation ion-exchange column and identified by SDS-PAGE and Western blot analysis. The proliferation inhibition activity of TRAIL-NT was detected by the MTT method, Wright-Giemsa staining assay, and FACS. The polyclonal antibody of TRAIL-NT was obtained after the BALB/C mice were immunized with purificated TRAIL-NT protein. Results showed that the target protein expressed in E. coli BL21(DE3) has the same molecular weight as that expected and could be recognized by anti-TRIAL Poly-Ab. The TRAIL-NT protein could also inhibit proliferation and induced apoptosis of Jurkat cells but no cytotoxicity to human liver cells and PBMC was observed. This preliminary research laid a solid foundation for further research on its biological activity and application in anti-tumor therapy.

In order to solve the problem of mission oriented aircraft fleet support station failure, an emergent reconfiguration method is proposed, which is based on disruption model. Firstly, the response process of aircraft fleet to disruption is analyzed and then a support station failure model is established. Through the application of Lagrange relaxation algorithm, the quantity constraints of support station are relaxed. A Lagrange heuristic algorithm is proposed, so as to generate emergent reconfiguration scheme with support stations failure. Eventually, a fleet of 20 aircrafts is studied for verification purposes. The result demonstrates that the proposed method can realize emergent reconfiguration of aircraft fleet support oriented to support stations failure.

In consideration of the uncertain disturbance caused by human error, the support problem is solved by means of establishing a mathematical programming model. According to the goal, the robust model is established in the paper and genetic algorithm is employed to solve the model. Through the application of the model, the robust optimization scheme is calculated, by which its performance and disturbance can be evaluated. Finally, case analysis demonstrates that the model is practical, which can provide reference for solving similar problem of working time disturbance.

High-performance thermoelectric materials require ultralow lattice thermal conductivity typically through either shortening the phonon mean free path or reducing the specific heat. Beyond these two approaches, a new unique, simple, yet ultrafast solid-state explosive reaction is proposed to fabricate nanoporous bulk thermoelectric materials with well-controlled pore sizes and distributions to suppress thermal conductivity. By investigating a wide variety of functional materials, general criteria for solid-state explosive reactions are built upon both thermodynamics and kinetics, and then successfully used to tailor material's microstructures and porosity. A drastic decrease in lattice thermal conductivity down below the minimum value of the fully densified materials and enhancement in thermoelectric figure of merit are achieved in porous bulk materials. This work demonstrates that controlling materials' porosity is a very effective strategy and is easy to be combined with other approaches for optimizing thermoelectric performance.

EPAC (Exchange Proteins Activated by cAMP) regulates glutamate transmitter release in the central neurons, but a role underlying this regulation has yet to be identified. Here we show that EPAC binds directly to the intracellular loop of an ATP-sensitive potassium (KATP) channel type-1 sulfonylurea receptor (SUR1) receptor consisting of amino acids 859–881 (SUR1859–881). Ablation of EPAC or expression of SUR1859–881, which intercepts EPAC-SUR1 binding, increases the open probability of KATPchannels consisting of the Kir6.1 subunit and SUR1. Opening of KATPchannels inhibits glutamate release and reduces seizure vulnerability in adult mice. Therefore, EPAC interaction with SUR1 controls seizure susceptibility and possibly acts via regulation of glutamate release.

High-performance thermoelectric materials require high-symmetry crystal structures that have large band degeneracies to yield good electronic properties. However, most of the semiconductors in nature possess low-symmetry crystal structures. In this study, the authors demonstrate a successful example of a high-performance thermoelectric material from a family of low-symmetry noncubic quaternary chalcopyrites. Three novel quaternary tetragonal chalcopyrites Cu2TMSnSe4 (TM = Mn, Fe, Co) have been selected based on their structure distortion parameters close to unity. This gives rise to a pseudocubic structure containing an inherently long-range cubic-like framework and localized lattice distortions. Thermoelectric properties of Cu2TMSnSe4 (TM = Mn, Fe, Co) from 300 to 850 K have been systematically investigated. Large Seebeck coefficients, moderate electrical conductivities, and high power factors are observed in these chalcopyrites, which are attributed to their high band degeneracies caused by the cubic-like cation framework. Meanwhile, the locally distorted noncubic anion frameworks lead to a low lattice thermal conductivity in Cu2TMSnSe4 (TM = Mn, Fe, Co). Consequently, high thermoelectric figures of merit with a maximum value of about 0.7 at 850 K have been achieved in these materials, representing some of the best values seen in quaternary chalcopyrites.

The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L) is a novel cytotoxic ligand belonging to the TNF superfamily which is currently being developed as a cancer therapeutic drug. Here, we observed the different functions of recombinant TRAIL protein with a foreign protein label and non-labeled TRAIL. We used a prokaryotic expression system to prepare two different versions of the extracellular TRAIL 114–281aa protein: TRAIL-HS, a protein modified with 6xHis-Tag and S-Tag; and TRAIL-FT, which had no foreign protein. The proteins were purified using Ni-NTA chromatography (TRAIL-HS) and cation ion-exchange column chromatography (TRAIL-FT) and identified by SDS-PAGE and western blot analysis. We compared the abilities of the proteins to bind to death receptor 5 (DR5) by ELISA and to induce apoptosis in a normal liver cell line (Chang liver) and a human T-lymphocyte leukemia cell line (Jurkat) by MTT assay, GR staining and FACS. The results indicate that the biological functions of TRAIL-FT were superior to those of TRAIL-HS in binding and the induction of apoptosis, and may be useful to further the development and applications of TRAIL.

The dynamical stability of iron under high-temperature and high-pressure conditions was investigated based on the phonons evaluated by using a recently developed method. It is revealed that both the fcc-Fe and the hcp-Fe are dynamically stable in a wide temperature and pressure range. The bcc-Fe phase can be stable as well, while in a limited temperature/pressure regime bounded by a dynamical stability limit and a harmonic limit. Direct evidence shows that it is the entropy term that plays a critical role in stabilizing the bcc-Fe under high-temperature and high-pressure conditions.