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In this work, 0.7BaTiO 3 -0.3Sr 0.2 Bi 0.7 TiO 3 (0.7BT-0.3SBT) ceramics with 0.15 mol% various rare-earth oxides doped are designed and synthesized by the conventional solid-state route. All prepared samples exhibited a single perovskite phase and dense microstructure with fine grain size (0.2–0.5 μm) after sintering at 1180 °C. Especially, the Gd-doped 0.7BT-0.3SBT ceramics exhibited excellent energy storage performances; the corresponding recoverable energy density and efficiency were 3.2 J/cm3 and 91.5% under an electric field of 330 kV/cm, respectively. Meanwhile, doping with Gd caused the BT-based ceramics to possess excellent temperature (30–150 °C) and outstanding frequency stabilities (10–1000 Hz). Moreover, the pulsed charge-discharge experiments revealed that a high power density of 59 MW/cm3 and a fast discharge speed of 110 ns with outstanding temperature stability could be synchronously obtained in the Gd-doped composition. All these features are attractive for pulsed power applications. [ABSTRACT FROM AUTHOR]

In this study, novel lead-free (1- x)Sr 0·7 Bi 0·2 TiO 3 - x La(Mg 0·5 Zr 0.5)O 3 ((1- x)SBT- x LMZ) ceramics were designed and fabricated by the conventional solid-state reaction method. The dielectric performance, energy storage characteristics and charge-discharge behavior of the ceramics were systematically investigated. Specifically, the temperature stability of dielectric constant is improved by doping SBT with LMZ. On a separate note, BDS is also enhanced ascribed to the reduction of the grain size. Consequently, the 0.87SBT-0.13LMZ exhibits high critical electric field of 340 kV/cm with ultrahigh efficiency (η) of 98.2% and recoverable energy storage density (W rec) of 1.22 J/cm3. Moreover, pulsed charge-discharge test elucidates that 0.87SBT-0.13LMZ possesses great thermal stability (30 °C–150 °C) along with a fast discharge period of 0.125 μs, high power density (P D) of 72.38 MW/cm3 as well as a high pulsed discharge energy density (1.2 J/cm3) at 380 kV/cm. Based on these outstanding characteristics, the 0.87SBT-0.13LMZ is considered as a potential candidate for pulse systems. [ABSTRACT FROM AUTHOR]

In this work, we designed novel lead-free relaxor ferroelectric ceramics of (1- x)BaTiO 3 - x Bi(Ni 1/2 Sn 1/2)O 3 (abbreviated as (1- x)BT- x BNS, with x = 0–0.20). With an increasing concentration of BNS, (1- x)BT- x BNS solid solutions displayed a phase transition from tetragonal symmetry to pseudocubic symmetry with highly diffusive and frequency-dependent relaxor ferroelectric behavior. Modified by BNS, (1- x)BT- x BNS ceramics yielded slim polarization-electric field (P - E) loops and improved energy-storage performances. The optimal energy storage properties can be achieved at x = 0.10, and samples showed a high recoverable energy density of 2.526 J/cm3 and a remarkably high energy efficiency of 93.89% under 240 kV/cm simultaneously at ambient temperature, which represent enhancements by 925% and 286%, respectively, over pure BaTiO 3. The energy storage characteristics of the 0.9BT-0.1BNS ceramic manifested good thermal stability (−55–150 °C) and frequency stability (10 Hz-1 kHz), with a variation in recoverable energy density of less than 10%. Meanwhile, the pulsed charging-discharging measurement showed that the 0.9BT-0.1BNS ceramic had a fast discharge period of 67 ns and a large power density of 19 MW/cm3. Due to the outstanding characteristics, there is potential for this new and environmentally friendly BT-based ceramic to be used in high-power pulse capacitor applications. [ABSTRACT FROM AUTHOR]

Dielectric capacitors with rapid discharge rates and high power density are the basis for advanced pulsed power systems. Sr 0.7 Bi 0.2 TiO 3 (SBT) is expected to be used in energy storage capacitors owing to the small hysteresis and high energy storage efficiency (η). Nevertheless, the low breakdown strength (BDS) limits the enhancement of energy storage density. This study explores the potential of Ho 2 O 3 -modified SBT to address this limitation. Introducing Ho reduces oxygen vacancies, decreases electrical conductivity, and increases thermal conductivity, thus enhancing BDS. The enhancement mechanism of electrical performance is studied through microscopic morphology analysis, structural refinement and numerical simulation. The Sr 0.7 Bi 0.15 Ho 0.05 TiO 3 exhibits remarkable properties, including ultra-low loss tanδ (0.1 %), ultra-high η (95.8 %), and outstanding thermal, frequency, and cycling stability in energy storage properties. Additionally, Sr 0.7 Bi 0.15 Ho 0.05 TiO 3 possesses a high power density (67.9 MW/cm3) and a rapid discharge rate (0.03 μs). The findings indicate that Sr 0.7 Bi 0.15 Ho 0.05 TiO 3 is a prospective material for energy storage capacitors. [ABSTRACT FROM AUTHOR]

Abstract Proton-conducting perovskite oxides such as doped barium cerate and barium zirconate are promising electrolytes for solid oxide fuel cells (SOFCs). Multiple-doped barium cerate perovskite oxide proton conductors of BaCe 0·7 Zr 0·1 Y 0.2-x Nd x O 3−δ (0 ≤ x ≤ 0.1) are prepared by solid state reaction and the properties of the fabricated material are characterized by various technologies. Nd doping improves the sinterability and Zr doping enhances the chemical stability in CO 2 atmosphere. The electrical conductivity order of the as-prepared electrolytes at elevated temperature in hydrogen atmosphere is: BaCe 0·7 Y 0·17 Zr 0.1 Nd 0.03 O 3−δ > BaCe 0·7 Y 0·2 Zr 0·1 O 3−δ > BaCe 0·7 Y 0·1 Zr 0.1 Nd 0.1 O 3−δ. Ethane is selectively dehydrogenated to ethylene with cogeneration of electrical power in the SOFC operated at 650–700 °C. The maximum power density of the SOFC is 123 mW cm−2 for ethane fuel and 138 mW cm−2 for hydrogen fuel at the 700 °C. These unique features make the multiple-doped barium cerate perovskite oxide a promising electrolyte for chemical-energy cogeneration in SOFCs. Highlights • BCZYN electrolyte with good sinterability and chemical stability toward CO 2. • 23% ethylene yield with 91% selectivity at 700 °C, co-generate 123 mW cm−2. • Environmentally friendly, without carbon dioxide emission. [ABSTRACT FROM AUTHOR]

Abstract: To solve the problem that traditional grey models were constructed on the hypothesis that the original data sequence is in accord with homogeneous index trend rather than non-homogeneous index trend. A novel grey forecasting model based on non-homogeneous index sequence approximately (abbreviated as NDGM) is proposed. It is proved that the models based on homogeneous index sequence are all special cases that of non-homogeneous index sequence. The recursive function of the NDGM model is proposed and the forecasting precision of the model based on pure non-homogeneous index sequence is discussed and the affine properties of the model are further studied. Finally, one numerical case is used to show the effective results of the proposed model. [Copyright &y& Elsevier]

Abstract: Although the grey forecasting model has been successfully employed in many fields and demonstrated promising results, its prediction results may be inaccurate sometimes. For the purposes of enhancing the predictive performance of grey forecasting model and enlarging its suitable ranges, this paper puts forward a novel grey forecasting model termed NGM model and its optimized model, develops a calculative formula for solving the parameters of the novel NGM model through the least squares method, and obtains the time response sequence of NGM model by using differential equation as a procedure for reasoning. It performs a numerical demonstration on the prediction accuracy of NGM model and its optimized models. As shown in the results, the proposed model and it optimized model can enhance the prediction accuracy. Numerical results illustrate that the proposed NGM model and its optimized model are effective. They are suitable for predicting the data sequence with the characteristics of non-homogeneous exponential law. This work makes important contribution to the enrichment of grey prediction theory. [Copyright &y& Elsevier]

Abstract: The integration of radio access networks with different radio access technologies (RATs) is one of the remarkable characteristics of the next-generation wireless networks (NGWNs). In NGWN, the users with multi-network interface terminals should be able to select independently radio access network to obtain the best service. Therefore, joint call admission control (JCAC) schemes are required to select the most appropriate radio access network (RAN) for incoming calls. We propose an immune algorithm-based JCAC (IA-JCAC) scheme with users centric in order to enhance user''s satisfaction. However, JCAC algorithms with users centric can lead to highly unbalanced traffic load among the available RANs in NGWN because users act independently, and most of them may prefer to be connected through a particular RAN. Highly unbalanced traffic load in NGWN will result in high overall call blocking/dropping probability and poor radio result utilization. To solve this problem, we employ dynamic pricing for balancing traffic load among available RANs in heterogeneous wireless networks where users'' preferences are considered in decision-making on RAT selection. The proposed IA-based JCAC scheme is compared with another scheme that does not use the dynamic pricing on the performance. The simulation result shows the effectiveness of the proposed IA-JCAC scheme is improved significantly. [Copyright &y& Elsevier]

Abstract: Uncertain decision-making is an important branch of decision-making theory. It is crucial to describe uncertain information, which determine the decision-making is effective or not. This paper first presents a brief survey of the existing methods on denoting uncertain information, such as fuzzy mathematics, stochastic and interval methods, analyzes the merits and demerits of these methods. Then the paper proposes a novel method grey systems theory to describe uncertain information and gives the novel definition of grey number on the basis of probability distribution. Subsequently a novel probability method on comparing grey numbers, especially discrete grey numbers and interval grey numbers, is studied. When an interval grey number satisfied to continuous uniform distribution, it will be degenerated into an interval number. Finally three numerical examples are investigated to demonstrate the effectiveness of the present method. [Copyright &y& Elsevier]

Abstract: As to the inherent simulant error of grey Verhulst model, this article presents unbiased grey Verhulst model. Recursive solutions are given under two initial conditions of the unbiased model. The results show the complete coincidence of the prediction and simulation to the original data of S-shaped curve generated form has achieved. The unbiased grey Verhulst model presented in this article has not only completely eliminated the inherent simulant error of the traditional model, but also avoided the jumping errors from the differential equation to differential equation in traditional grey modeling. Case analysis shows that the simulation and prediction accuracy in traditional modeling has been significantly improved by unbiased grey Verhulst model. [ABSTRACT FROM AUTHOR]

Abstract: Although the grey forecasting model has been successfully adopted in various fields and demonstrated promising results, the literatures show its performance could be further improved. For this purpose, this paper proposes a novel discrete grey forecasting model termed DGM model and a series of optimized models of DGM. This paper modifies the algorithm of GM(1,1) model to enhance the tendency catching ability. The relationship between the two models and the forecasting precision of DGM model based on the pure index sequence is discussed. And further studies on three basic forms and three optimized forms of DGM model are also discussed. As shown in the results, the proposed model and its optimized models can increase the prediction accuracy. When the system is stable approximately, DGM model and the optimized models can effectively predict the developing system. This work contributes significantly to improve grey forecasting theory and proposes more novel grey forecasting models. [Copyright &y& Elsevier]

Abstract: This article studies the problem about optimizing replacement policy for a repairable queuing system where the repairman takes multiple vacations. We assume that the service station after a repair is not “as good as new” and the duration of repairman vacation is either random variational or regular constant. We optimize the number N of the customers that have been served at the service station to achieve the maximum long-run profit per unit time. Both working time and repair time are assumed to be geometric processes. The explicit expressions of the objective function is derived in this article, and a detailed and in-depth discussion is offered. [ABSTRACT FROM AUTHOR]

Abstract: The grey systems theory aims at the objects that their information is inadequate and this situation is general in reality. It has been urgent work to study the uncertain problems using the missing information. With the help of the simple introduction of grey systems theory, we further study the covered operation and get some calculation rules about grey number. The definition of grey matrix (GM) and its covered operation are proposed. Particularly, some results of the inverse grey matrix are obtained. Also with the help of the proposed grey matrix theory and the traditional input–output analysis, we propose the grey input–output analysis. The most important results are the computational formulas and their rigorous proofs of the matrix-covered set of the inverse grey Leontief coefficient’s matrix. It provides an effective tool to study an economic system by the input–output analysis under the uncertain situation. The modified case verifies the effectiveness of our methodology. [Copyright &y& Elsevier]

Abstract: This article has proved that discrete function with homogeneous exponential law will become discrete function with non-homogeneous exponential law if the function with homogeneous exponential law accumulates, while discrete function with homogeneous exponential law is generated by inversely accumulating the discrete function with non-homogeneous exponential law. Based on the error analysis of the model GM(1,1), researchers use the discrete function with non-homogeneous exponential law to fit the accumulated sequence in order to propose a new method for optimizing background value in model GM(1,1). There are plenty of data simulations and models. And it shows that the new model broke through restrictions of using coefficient, and it still improved its matching and prediction precision. [Copyright &y& Elsevier]

This study delves into the synthesis and characterization of rare earth germanate La 4 GeO 8 ceramics, employing the solid-phase reaction method, with a focus on their microwave dielectric properties and crystallographic characteristics. The research employs X-ray diffraction (XRD) and transmission electron microscopy (TEM) to ascertain the orthorhombic crystal structure within the Pnma space group. Rietveld refinement analysis precisely determines the lattice constants (a = 18.3006 Å, b = 7.6697 Å, c = 5.8513 Å) and unit cell volume (V = 821.28429 Å3). Raman spectroscopy provides insights into the correlation between the quality factor (Q × f) and the Full Width at Half Maximum (FWHM) of the A g (O) mode at 733 cm⁻1. A notable highlight of the study is the exceptional microwave dielectric performance of La 4 GeO 8 ceramic sintered at 1540 °C, characterized by a relative dielectric constant (ε r) of 13.24, a Q × f product of 47,826 GHz at 10.16 GHz, and a temperature coefficient of frequency (τ f) of −82.3 ppm/°C. This comprehensive investigation offers valuable insights into the structural and microwave dielectric properties of AB-type rare earth germanate La 4 GeO 8 ceramics, underscoring their potential in advanced dielectric material applications. [ABSTRACT FROM AUTHOR]

• The introduction of Ca inhibits the grain growth and reduces oxygen vacancies. • The optimal composition exhibits ultra-high dielectric breakdown strength. • The optimal composition exhibits ultra-high energy storage density and efficiency. • The optimal composition shows excellent stability of temperature and frequency. • The optimal composition exhibits high power density. Sr 0.7 Bi 0.2 TiO 3 with high relaxor behavior and energy storage efficiency (η) is expected to be applied in power energy storage capacitors. However, its energy storage density is limited by the relatively low dielectric breakdown strength (DBS). Herein, Sr 0.7 Bi 0.2 Ca x TiO 3 (SBT-xC, x = 0 ∼ 0.15) was prepared to decrease the average grain size of Sr 0.7 Bi 0.2 TiO 3. This can effectively eliminate the oxygen vacancy and decrease the electrical conductivity and leakage current, which result in the enhanced DBS. Meanwhile, Ca doping increases the relaxor behavior and dielectric constant. When x = 0.1, the composition exhibits high DBS of 480.2 kV/cm and excellent energy storage properties, such as high energy storage density of 2.1 J/cm3 with high η of 97.6 % at 290 kV/cm, considerable thermal stability and great frequency stability. Moreover, SBT-0.1C shows high power density of 50.1 MW/cm3. These results suggest that SBT-0.1C is a potential candidate for high performance dielectric energy storage applications. [ABSTRACT FROM AUTHOR]

One-dimensional nanostructured CuCo 2 O 4 -Sm 0.2 Ce 0.8 O 1.9 (SDC) nanofibers are prepared by the electrospinning method and one step sintering as a cathode with low polarization resistance for intermediate temperature solid oxide fuel cells (IT-SOFC). The CuCo 2 O 4 -SDC nanofibers cathodes form a porous network structure and have large triple-phase boundaries. Correspondingly, the electrochemical performance of the CuCo 2 O 4 -SDC nanofibers composite cathodes shows significantly improve, achieving the polarization resistance of 0.061 Ω cm2 and the maximum power densities of 976 mW·cm−2 at 750 °C. Thus, these results suggest that CuCo 2 O 4 -SDC nanofiber could be a highly active cathode material for IT-SOFCs. • CuCo 2 O 4 -Sm 0.2 Ce 0.8 O 1.9 nanofibers are prepared by a one-step method. • Porous network cathode possesses a large surface area. • Spinel cathode materials demonstrate low polarization resistance. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive investigation into the dielectric properties of LiY 9 Si 6 O 26 ceramics, which were prepared for the first time using the solid-state method. XRD patterns and Rietveld refinement analysis conclusively demonstrate that LiY 9 Si 6 O 26 adopts a hexagonal crystal structure with space group P63/m (176). Furthermore, Raman spectroscopy reveals a significant correlation between the quality factor and the FWHM of the A 1g (O) mode at 879 cm−1. Transmission electron microscopy (TEM) was employed to verify the ordered layered structure inherent in the hexagonal LiY 9 Si 6 O 26 ceramics. The microstructure of the ceramic grains was analysed using scanning electron microscopy (SEM), which revealed a remarkably high relative density of 96.4% for the LiY 9 Si 6 O 26 ceramic. The Si–O bond valences (V Si – O) were found to be closely associated with the τ f in LiY 9 Si 6 O 26 ceramics. Remarkably, the microwave dielectric properties of LiY 9 Si 6 O 26 ceramics sintered at 1425 °C were ascertained to be ε r = 10.54, Q × f = 25,579 GHz (f = 10.3 GHz), and τ f = 2.64 ppm/°C. These outstanding properties position LiY 9 Si 6 O 26 ceramics as promising candidates for high-performance dielectric materials. [ABSTRACT FROM AUTHOR]

In this study, the Li 2+ x Mg 3 SnO 6 (L x MS) ceramic systems were prepared by solid-state reaction using novel atmosphere-controlled sintering ( x = 0.00–0.12). The influences of extra lithium contents on the phase evolution, crystal structure and microwave dielectric properties of Li 2+ x Mg 3 SnO 6 (L x MS) ceramics were systematically investigated. As samples were calcined from 800 to 1000 °C, the Li 2 Mg 3 SnO 6 phase was formed from the chemical reaction between Li 2 SnO 3 and MgO phase. Pure Li 2 Mg 3 SnO 6 phase could be observed for samples calcined at 1000–1100 °C. But when it was exposed to high temperature air over 1100 °C, the Li 2 Mg 3 SnO 6 decomposed into Mg 2 SnO 4 , MgO and Li 2 O. Because of the protective atmosphere and extra lithium, the ε r , Q×f and τ f were significantly improved by the suppression of secondary phase and pores for 0.00 ≤ x ≤ 0.08 . However, comprehensive microwave characteristics were deteriorated for 0.08 < x ≤ 0.12 , which were correlated with dielectric polarization, bond valence, FWHM, packing fraction and octahedral distortion. The excellent microwave characteristics of L x MS ( x = 0.08) sintered at 1350 °C in novel controlled atmosphere were obtained : ε r = 12.7, Q×f = 168,330 GHz and τ f = −27.4 ppm/°C. [ABSTRACT FROM AUTHOR]

Microwave dielectric properties of Li 2 Mg 3− x Ca x TiO 6 (x=0–0.18) ceramics were studied using a conventional solid-state route to find temperature stable and high Q microwave ceramics. As the calcination temperature was 500 °C, the Li 2 TiO 3 phase with monoclinic rock salt structure in C 2 /c space group started to form. When the samples were calcined from 600 °C to 900 °C, the XRD patterns exhibited a remarkable chemical reaction between the MgO and Li 2 TiO 3 phases, which eventually formed the Li 2 Mg 3 TiO 6 phase. The results indicated the Li 2 Mg 3 TiO 6 and CaTiO 3 co-existed with each other and formed a stable composite system when the calcium content was added. The SEM photographs indicated that the pores caused by the Li evaporation could be effectively reduced due to the appearance of CaTiO 3 . As x was increased from 0 to 0.18, the relative density was significantly improved due to the elimination of pores. As the Ca content increased, the dielectric constant (εr) increased from 14.8 to 20.6; the quality factor (Q×f) decreased from 148,713 GHz to 79,845 GHz, and the temperature coefficient of resonant frequency (τf) significantly increased from −42.4 to +10.8 ppm/°C due to the increased amount of CaTiO 3 . Therefore, at x=0.12, the LMC x T ceramics sintered at 1280 °C for 6 h displayed excellent comprehensive properties of εr=17.8, Q×f =102,246 GHz and τf=−0.7 ppm/°C. [ABSTRACT FROM AUTHOR]

The formation of secretory cavities in Rutaceae has been the subject of great interest. In this study, cytological events that are involved in the lysigenous formation of the secretory cavities in the leaves of Dictamnus dasycarpus are characterized by an interesting pattern of programmed cell death (PCD). During the developmental process, clusters of cells from a single protoepidermal cell embark on different trajectories and undergo different cell death fates: the cell walls of the secretory cells have characteristics of thinning or complete breakdown, while the sheath cells present a predominantly thick-walled feature. A DAPI assay shows deformed nuclei that are further confirmed to be TUNEL-positive. Gel electrophoresis indicates that DNA cleavage is random and does not result in ladder-like DNA fragmentation. Ultrastructurally, several remarkable features of PCD have been determined, such as misshapen nuclei with condensed chromatin and a significantly diffused membrane, degenerated mitochondria and plastids with disturbed membrane systems, multivesicular bodies, plastolysomes, vacuole disruption and lysis of the center secretory cell. Cytological evidence and Nile red stains exhibit abundant essential oils accumulated in degenerated outer secretory cells after the dissolution of the center secretory cell. In addition, explanations of taxonomic importance and the relationship between PCD and oil droplet accumulation in the secretory cavities are also discussed. [ABSTRACT FROM AUTHOR]

The internal ring stiffeners have been commonly introduced in tubular joints to improve the ultimate strength and fatigue life of offshore structures. However, for internally ring-stiffened multi-planar tubular joints which are frequently used in practical application, few investigations about stress concentration factor (SCF) in the joints have been reported so far and no parametric equation of the SCF is currently available for fatigue design. In this paper, the effects of geometrical parameters on the SCF distribution along the weld toe of the internally ring-stiffened two-planar tubular KK joints under axial loading are investigated by performing a set of three-dimensional (3D) FE stress analyses. Firstly, based on the requirements of AWS D1.1-2010, an approximate model of the actual weld profile is proposed. Then, several 3D FE models of various tubular joints are established to verify the proposed model. Subsequently, the effects of multi-planarity and stiffeners on the SCF in two-planar tubular KK joints are investigated. Additionally, the influence of geometrical parameters on both the SCF and the SCF distribution of the joints under axial loading is studied. Finally, SCF parametric equations for fatigue design of the internally ring-stiffened two-planar tubular KK joints under axial loading are developed from nonlinear regression analysis. • SCF distribution of internally ring-stiffened tubular KK joints is studied by using an approximate model. • The effect of geometrical parameters on the SCF distribution of the joints is investigated. • SCF parametric equations of the joints under axial loading are developed. [ABSTRACT FROM AUTHOR]

Abstract: A hybrid approach integrating OWA (Ordered Weighted Averaging) aggregation into TOPSIS (technique for order performance by similarity to ideal solution) is proposed to tackle multiple criteria decision analysis (MCDA) problems. First, the setting of extreme points (ideal and anti-ideal points) in TOPSIS is redefined and extended for handling the multiple extreme points situation where a decision maker (DM) or multiple DMs can provide more than one pair of extreme points. Next, three different aggregation schemes are designed to integrate OWA into the TOPSIS analysis procedure. A numerical example is provided to demonstrate the proposed approach and the results are compared for different aggregation settings and confirm the robustness of rankings from different scenarios. [ABSTRACT FROM AUTHOR]

The Li 4 MgWO 6 ceramic was synthesized by the conventional solid-state reaction method, and its sintering behavior and microwave dielectric properties were studied for the first time. The XRD patterns and structural refinements indicated that Li 4 MgWO 6 formed an orthorhombic phase at temperatures above 900 °C, and TEM analyses confirmed the ordered and layered rock-salt superstructures for the orthorhombic Li 4 MgWO 6. The SEM photographs and relative density curve showed that the sample sintered at 950 °C had the highest densification. When sintered at 950 °C in a WO 3 -rich atmosphere for 4 h, Li 4 MgWO 6 had the following optimum properties: ε r = 15.06±0.33, Q × f = 28,300±600 GHz (f = 10.1 GHz), and τ f = 0.9±3.4 ppm/°C. Compared with other reported low permittivity compounds, Li 4 MgWO 6 shows more potential for the Low-Temperature Cofired Ceramics (LTCC) substrate materials due to its intrinsic low sintering temperature, novel temperature stability, and relatively low dielectric loss. [ABSTRACT FROM AUTHOR]

Using the first-principles calculations within the density functional-theory (DFT) framework, we theoretically investigated the surface reconstruction, surface states near the Fermi level and their passivation on CuIn 0.75 Ga 0.25 Se 2 (1 1 2) (CIGS) surface by chlorine, fluorine and hydrogen. Surface reconstruction appears on CIG-terminated CIGS (1 1 2) surface and it is a self-passivation. For the locations of Cl, F and H atoms adsorbing on Se-terminated CIGS (1 1 2) surface, four high symmetry adsorption sites: top sites, bridge sites, hexagonal close-packed (hcp) sites and faced centered cubic (fcc) sites were studied respectively. With the coverage of 0.5 monolayer (ML), Cl, F and H adatoms energetically occupy the top sites on the CIGS (112) surface. The corresponding adsorption energies were −2.20 eV, −3.29 eV, −2.60 eV, respectively. The bond length and electronic properties were analyzed. We found that the surface state density near the Fermi level was markedly diminished for 0.5 ML Cl, F and H adsorption on Se-terminated CIGS (1 1 2) surface at top sites. It was also found that H can more efficiently passivate the surface state density than Cl and F atoms, and the effect of adsorption of Cl atoms is better than that of F. [ABSTRACT FROM AUTHOR]

Usually, the quality factor of a binary-phase ceramic will increase if the volume molar ratio of the high quality factor component increases, and vice versa. However, the quality factor of the Ba 6-3 x Ln 8+2 x Ti 18 O 54 - LnAlO 3 (Ln = Nd, Sm, La) ceramics keeps a constant (~ 2200 ± 200 at 4 GHz) as the volume molar ratio of LnAlO 3 (~ 9000 at 7 GHz) increases. While previous studies reported the importance of microstructure variation, here by fitting the dielectric constant, via definition we derived a quality factor calculation formula that can precisely determine the quality factor as the volume molar ratio changes, which is of great significance for guiding the ceramic manufacturing. [ABSTRACT FROM AUTHOR]

In cognitive wireless network, throughput scheduling optimization under interference temperature constraints has attracted more attentions in recent years. A lot of works have been investigated on it with different scenarios. However, these solutions have either high computational complexity or relatively poor performance. Throughput scheduling is a constraint optimization problem with NP(Non-deterministic Polynomial) hard features. In this paper, we proposed an immune-clone based suboptimal algorithm to solve the problem. Suitable immune clone operators are designed such as encoding, clone, mutation and selection. The simulation results show that our proposed algorithm obtains near-optimal performance and operates with much lower computational complexity. It is suitable for slowly varying spectral environments. [ABSTRACT FROM AUTHOR]

Trehalose represents the main hemolymph sugar in many insects, and it functions in energy metabolism and protection in extreme environmental conditions. To gain an insight into trehalose functions in Delia antiqua diapausing pupae, genes encoding trehalose-6-phosphate synthase ( TPS ), trehalose-6-phosphatase ( TPP ) and trehalase ( TRE ) were identified and characterized. Analysis of the deduced amino acid sequences indicated that these genes were highly similar to each homolog from Diptera insects. Gene expressions and their enzyme activities were also investigated. The differential expressions of TPS and TPP shared very similar trends for summer and winter diapausing pupae. Their enzyme activities were consistent with the gene expressions. Trehalose concentrations in summer- and winter-diapausing pupae were lower at the initial phase (4.37–5.09 μg/mg) but increased gradually and peaked in the maintenance phase (10.59–14.36 μg/mg); the concentrations then declined in the quiescence phase. We speculated that a higher trehalose content during the maintenance stage may contribute to protein and/or biological membrane stabilization in winter or to desiccation resistance in the summertime. Diapause termination requires a decrease in the trehalose concentration to promote pupal–adult development. The glucose content also varied during the diapausing processes. Our results provide an overview of the differential expression levels of trehalose metabolic enzymes, confirming the important roles of trehalose in diapausing pupae of the onion maggot. Further work remains to explore its actual functions. [ABSTRACT FROM AUTHOR]

• A facile electrochemical sensor was designed for MEL detection. • The sensor was prepared by directly deposition of electroactive materials Fc-ECG on SPCE based on that MEL can enhance the electrochemical signal of Fc-ECG. • The sensor was used for MEL detection in milk samples. • A portable detection system with potential application in POCT was constructed. Excessive intake of melamine (MEL) can be harmful to human health, and it is important to establish a rapid and accurate MEL detection method. As the electrochemical activity of MEL is very low, ferrocenylglutathione (Fc-ECG) was used as an electron transfer mediator to assist with the detection of MEL using screen-printed carbon electrode (SPCE). This modified electrode (MEL/Fc-ECG/SPCE) was prepared by stepwise drop-casting and was fully characterized. Results showed that MEL significantly enhanced signal of Fc-ECG/SPCE sensor due to the three p-π conjugated double bonds that facilitated electron transfer. Under optimal conditions, the sensor exhibits two linearities in the range of 0.20–2.00 μM and 8.00–800 μM, with a sensitivity of 15.03 μA·μM−1·cm−2. The selectivity, stability, and reproducibility were investigated and successfully used to detect MEL in raw milk and confirms safety verification of foods. Moreover, a portable testing platform was designed for MEL detection based on a CH32 chip. [ABSTRACT FROM AUTHOR]

Abstract: To gain a better understanding of the molecular mechanisms regulating pupal diapause of the onion maggot Delia antiqua, PCR-based suppressive subtractive hybridization was performed to identify genes involved in summer and/or winter diapause. A total of 209 unique sequences were obtained including 89 in forward library for winter diapausing pupae and 120 in the reverse library for summer diapausing pupae. 76.4% (68/89) and 68.3% (82/120) unique sequences had significant hits to non-redundant proteins database. Gene functional annotation showed these non-redundant sequences are involved in stress response and innate immunity, metabolism and energy, information processing and regulation, binding, food storage, morphogenesis and development, cell skeleton and cycle, protein synthesis and folding. Approximately 28.2% (59/209) transcripts showed no significant similarity to any other sequence in the public databases, probably representing unique genes of the onion maggot. Semi-quantitative RT-PCR revealed that the relative expression levels of 18 genes were comparable between summer and winter diapause. This study elucidates the temporal expression of diapause-related genes in onion maggot, also provides new insights into the differences in the physiological changes in summer and winter pupae. Functional characterization of some candidate genes will further enhance the understanding of the generating, maintaining, and breaking mechanism of diapause. [Copyright &y& Elsevier]