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A dual-wavelength continuous-wave (CW) diode-pumped Nd:YVO4 laser that generates simultaneous laser action at the wavelengths 914 and 1342 nm is demonstrated. A total dual-wavelength output power of 1.79 W was achieved at the incident pump power of 18.2 W. Furthermore, intracavity sum-frequency mixing at 914 and 1342 nm was then realized in a LBO crystal to reach the yellow-green range. We obtained a total CW output power of 212 mW at 544 nm.

Mn-doped ZnO (Zn1−xMnxO, 0 ≤ x ≤ 0.1) films are prepared by an ultrasonic spray assisted chemical vapor deposition method. X-ray diffraction and Raman scattering show that all the Zn1−xMnxO films are good wurtzite structures without any impurity phases. Cathodoluminescence spectra show that ultraviolet emission and green luminescence can be observed. The intensity of ultraviolet emission decreases with the increment of x, while the intensity of green luminescence increases with the increment of x when x ≤ 0.02. However, when x (x > 0.02) is further increased, the intensity of green luminescence decreases gradually, and the green luminescence disappears when x is above 0.075. We consider that the change of the luminescence is related to the competition between the radiative recombination and the non-radiative recombination.

This paper presents a primary droop current-sharing controller that can integrate into voltage feedback controller and, thus, provides a low-cost and simple solution for parallel DC/DC converters system. From the equivalent small-signal model, a two-port network was adapted to describe the output and control variables for designing voltage and droop current-sharing loops. From the analysis results, the designed primary droop current-sharing controller will not affect the original voltage loop gain profile to let the DC/DC converter preserve desire control performance. After designing a stable DC/DC converter with primary droop current-sharing control, the stability of the interconnected parallel DC/DC converters system was studied. When the cable resistance is reduced, when the cable resistance is reduced, the interconnected system might be unstable. Finally, some simulation and experimental results demonstrated the effectiveness of the proposed controller in a prototype parallel DC/DC converters system.

Well-aligned ZnO nanorods and Mn-doped ZnO nanorods are fabricated on Si (1 0 0) substrate according to the contribution of Zn metal catalysts. Scanning electron microscopy and high-resolution transmission electron microscopy images indicate that the influence of Zn catalyst on the properties of ZnO can be excluded and the growth of ZnO nanorods follows a vapor–liquid–solid and self-catalyzed model. Mn-doped ZnO nanorods show a typical room temperature ferromagnetic characteristic with a saturation magnetization ( M S ) of 0.273 μ B /Mn. Cathodoluminescence suggests that the ferromagnetism of Mn-doped ZnO nanorods originates from the Mn 2+ –Mn 2+ ferromagnetic coupling mediated by oxygen vacancies. This technique provides exciting prospect for the integration of next generation Si-technology-based ZnO spintronic devices.

c -Axis-oriented and (1 1 7)-oriented Bi 3.25 La 0.75 Ti 3 O 12 (BLT) thin films are successfully controlled by the intermediate layer of LaNiO 3 (LNO) with chemical solution deposition (CSD), respectively. X-ray diffraction (XRD) demonstrates that the structure and orientation of LNO thin films have a strong effect on the orientation of BLT thin films. Scanning electron microscopy suggests that BLT thin films on LNO electrode exhibit crack-free, uniform size grains and dense microstructure. A crystalline orientation dependent remanent polarization is observed in BLT thin films, and it is found that the remanent polarization (2 P r ) of (1 1 7)-oriented films is larger than that of c -axis-oriented films. Our research directly demonstrates that the vector of the main spontaneous polarization in these layered perovskite materials (BLT) is along a -axis.

In this paper, we consider parallel identical machines scheduling problems with a deteriorating maintenance activity. In this model, each machine has a deteriorating maintenance activity, that is, delaying the maintenance increases the time required to perform it. We need to make a decision on when to schedule the deteriorating maintenance activities and the sequence of jobs to minimize total completion time. We provide a polynomial time algorithm to solve the total completion time minimization problem.

We present the first results of radio timing observations of binary and millisecond pulsars in China. We have timed four binary pulsars for 9 years, using Nanshan 25-m radio telescope. The long time span has enabled us to determine their rotation and orbital parameters.

Thin films of Bi 3.15 Nd 0.85 Ti 3 O 12 (BNT) and Bi 3.15 Nd 0.85 Ti 3 − x Zr x O 12 (BNTZ x , x = 0.1 and 0.2) were fabricated on Pt/TiO 2 /SiO 2 /Si(100) substrates by a chemical solution deposition (CSD) technique at 700 °C. Structures, surface morphologies, leakage current characteristics and Curie temperature of the films were studied as a function of Zr ion content by X-ray diffraction, atomic force microscopy, ferroelectric test system and thermal analysis, respectively. Experimental results indicate that Zr ion substitution in the BNT film markedly decreases the leakage current of the film, while almost not changing the Curie temperature of the film, which is at about 420–460 °C. The decrease of the leakage current in BNTZ x films is that the conduction by the electron hopping between Ti 4+ and Ti 3+ ions is depressed because Zr 4+ ions can block the path between two adjacent Ti ions and enlarge hopping distance.

Propeller-like ZnO nanostructures are fabricated by a physical vapor deposition method. This structure exhibits a good field emission characteristic with a turn-on field of 4.36 V/μm. Cathodoluminescence studies suggest that the high current density in the surface is attributed to the main reason causing good field emission characteristic.

The paper discussed the genetic relationship between superior individual late-maturity Yurongwanli and other cultivars. To do so POD isoenzyme and RAPD technology were used to analyze litchi germplasm resources of Fuqing city. There were 4 bands produced by POD isoenzyme electrophoresis. According to the differences of these bands, Shishengshu1, Shishengshu2, Xiafanzhi and Dongliuyihao were put in the frist category, while Shangfanzhi and Yuanhong were placed in the second category. RAPD-PCR analysis showed that seven primers produce a total of 59 bands, with 8.43 fragments per prime. Among these 59 bands 40 were polymorphic, with a 67% polymorphism rate. The DPS2000 software was used to analyze the RAPD genotype date matrix. The result showed that the 7 cultivars can be divided into two categories when the genetic distance D value is 0.70 and four categories when the D value is 0.60. These two results indicated that Yurongwanli has the closest genetic relationship with Hongxiuqiu.

This paper reviewed the research on germplasm resources and breeding of longan in the past decade in China. The past decade has seen great progress in the research on germplasm resources and breeding of longan in China. Germplasm resources have been collected and conserved in various ways, such as germplasm bank, plantlet bank in vitro, and cryoconservation, etc; Traditional research technologies such as morphology, palynology, and isozymology, etc. have been improved, molecular markers such as RAPD, ISSR, and AFLP, etc. have become main technologies in taxonomy and genetic relationship. Single seedling selection has been developed into combination of multiple methods such as seedling selection, sports selection, and sexual crossing, and biotechnological breeding, etc. breeding research. Breeding targets which mainly pursued high and stable yield before have been changed into cultivars with early or late ripening, special qualities (high-content sugar, large fruit, aborted seed, and unique flavors, etc.), and high and stable yields. Cultivars have been managed by ways of examination and approval, certification and registration, etc. in local governments departments in main production areas. In addition, urgent problems have been analyzed, and the further directions and foci in future have been proposed in research on germplasm resources and breeding of longan in China.

We present our initial results from a study of 14 (U)LIRGs with a doublenucleus ( z

In this paper we consider the single-machine scheduling problems with a sum-of-actual-processing-time-based learning effect. By the sum-of-actual-processing-time-based learning effect, we mean that the processing time of a job is defined by a function of the sum of the actual processing time of the already processed jobs. We show that even with the introduction of the sum-of-actual-processing-time-based learning effect to job processing times, the makespan minimization problem, the total completion time minimization problem, the total completion time square minimization problem, and some special cases of the total weighted completion time minimization problem and the maximum lateness minimization problem remain polynomially solvable, respectively.

The effects of thickness on the microstructure and ferroelectric properties of Bi 3.15 Nd 0.85 Ti 3 O 12 (BNT) thin films prepared by chemical solution deposition were studied. It was found that the grain size and residual stress are not sensitive to the film thickness in our studied thickness of 160–440 nm. However, the ferroelectric properties depend strongly on the film thickness. The mechanism concerning the dependence of ferroelectric properties of BNT films on the film thickness was discussed.

Nd-substituted bismuth titanate (Bi3.15Nd0.85Ti3O12, BNT) nanotube arrays are fabricated by means of a sol–gel method utilizing porous anodic aluminum oxide (AAO) template. The morphologies and structures have been determined by scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The diameter and length of these nanotubes are about 200 nm and 60mm, respectively, and their wall thickness is about 30 nm. The average grain size is around 40 nm. XRD data show that the BNT nanotubes possess bismuth-layered perovskite structure. High-resolution electron microscopy (HRTEM) image demonstrates that the BNT nanotubes are polycrystalline. Polarization–electric field (P–E) response curves of BNT nanotube arrays were measured, and a size induced polarization reduction phenomenon is observed.

In this work, we demonstrate nano-structured silver particles photo-reduced from silver nitride (AgNO3) solution using visible-light-activated titanium dioxide (TiO2), which can be a convenient and effective substrate for surface enhanced Raman spectroscopy (SERS) observation. Visible-light-activated carbon-containing TiO2 nanoparticles are applied to photo-reduce and form nano-structured silver from AgNO3 upon visible-light illumination. Photo-reduced nano-structured silver is used as an active substrate for SERS studies of TiO2 as well as nano diamond and TiO2. The photo reduction of AgNO3 and SERS observation can be obtained by simultaneously using the same visible laser excitation. The coexistence of the anatase phase with small admixture of the rutile phase in the TiO2 can be observed using SERS. The carbon structure in the carbon-containing TiO2 was determined to be sp2 type carbon bonding by SERS. Copyright © 2009 John Wiley & Sons, Ltd.

The paper deals with the single machine scheduling problems with a time-dependent learning effect and deteriorating jobs. By the effects of time-dependent learning and deterioration, we mean that the processing time of a job is defined by function of its starting time and total normal processing time of jobs in front of it in the sequence. It is shown that even with the introduction of a time-dependent learning effect and deteriorating jobs to job processing times, the single machine makespan minimization problem remain polynomially solvable. But for the total completion time minimization problem, the classical shortest processing time first rule or largest processing time first rule cannot give an optimal solution.

Aiming at the influence of substitution on ferroelectric behaviors, Nd and Mg / Mn cosubstituted bismuth titanate films, Bi 3.15 Nd 0.85 Ti 2.97 Mg 0.03 O 12 (BNTMg) and Bi 3.15 Nd 0.85 Ti 2.95 Mn 0.05 O 12 (BNTMn), have been prepared on Pt / Ti / SiO 2/ Si (100) substrates at 700°C by a chemical solution deposition technique, respectively. A series of comparisons including structures, surface morphologies, and ferroelectric properties of the as-prepared films were carried out by X-ray diffraction, scanning electron microscope, and a Radiant Technologies Precision Workstation for ferroelectric test system. It was found that the films possess preferred the (117) and (00l)-oriented polycrystalline structures, and the remnant polarization of BNTMg film is larger than that of BNTMn film and the coercive field of BNTMn film is lower than that of BNTMg film. The values of 2Pr and 2Ec of BNTMg and BNTMn are 28 μC/cm2 and 212 kV/cm, and 15 μC/cm2 and 175 kV/cm, respectively. The relevant physical mechanisms were pursued.

Formation of self-organized Ga(AsSb) quantum-islands during growth is shown to occur in a series of Ga(AsSb)/GaAs/(AlGa)As heterostructures, resulting in an in-plane hole confinement of several hundred meV. The shape of the in-plane confinement potential is nearly parabolic and thus yields almost equidistant hole energy levels. Transmission electronmicroscopy reveals that the quantum islands (QIs) are 100 nm in diameter and exhibit an inplane variation of the Sb concentration of more than 30%, which is the origin of the confinement. Up to seven bound hole states are observed in the photoluminescence spectra. Time-resolved photoluminescence data are shown as function of excitation density. The influence of size and density of such structures as well as the mechanisms of growth are discussed. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Aiming at the influence of substitution on ferroelectric behaviors, Nd and Mg/Mn cosubstituted bismuth titanate films, Bi3.15Nd0.85Ti2.97Mg0.03O12 (BNTMg) and Bi3.15Nd0.85Ti2.95Mn0.05O12 (BNTMn), have been prepared on Pt/Ti/SiO2/Si(100) substrates at 700°C by a chemical solution deposition technique, respectively. A series of comparisons including structures, surface morphologies, and ferroelectric properties of the as-prepared films were carried out by X-ray diffraction, scanning electron microscope, and a Radiant Technologies Precision Workstation for ferroelectric test system. It was found that the films possess preferred the (117) and (00l)-oriented polycrystalline structures, and the remnant polarization of BNTMg film is larger than that of BNTMn film and the coercive field of BNTMn film is lower than that of BNTMg film. The values of 2Pr and 2Ec of BNTMg and BNTMn are 28 μC/cm2 and 212 kV/cm, and 15 μC/cm2 and 175 kV/cm, respectively. The relevant physical mechanisms were pursued.

The concentrations of extractable organohalogens (EOX) and extractable persistent organohalogens (EPOX) in placenta, umbilical cord and hair of mothers delivering disabled or normal newborns as well as the compositions of EPOCl in three analyzed matrices were determined by a combination of NAA, gas chromatography and chemical separation. The results indicated that both EOX and EPOX decreased in the order: hair > umbilical cord > placenta. Organochlorines were the major fraction of organohalogens. More than 77% of EPOCl were unidentified. High organohalogens exposure may induce adverse health effects, and hair, as a biomonitor for organohalogens assessment, is more recommendable.

Nd 3+ /V 5+ -cosubstituted Bi 4 Ti 3 O 12 (Bi 3.15 Nd 0.85 Ti 2.97 V 0.03 O 12 , BNTV) thin films are prepared on Pt/Ti/SiO 2 /Si(1 0 0) substrates by a chemical solution deposition (CSD) technique. The structure and surface morphology of the films are analyzed using X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy, respectively. The electrical properties of BNTV films are investigated as a function of annealing temperatures. The remanent polarization, dielectric constant and capacitance of the BNTV thin films increase with the increase of annealing temperatures in the range of 650–750 °C. After annealing at 750 °C, the BNTV film exhibits good polarization fatigue characteristics at least up to 1×10 10 switching cycles at a frequency of 100 kHz and excellent retention properties up to 1×10 5 s.

Effects of extrapolation length on the phase transformation of epitaxial ferroelectric thin films on dissimilar cubic substrates have been studied on the basis of the mean-field Landau–Ginzburg–Devonshire (LGD) thermodynamic theory by taking an uneven distribution of the interior stress with thickness into account. It was found that the polarization of epitaxial ferroelectric thin films is strongly dependent on the extrapolation length of films. The physical origin of the extrapolation length during the phase transformation from paraelectric to ferroelectric was revealed in the case of ferroelectric thin films.

Mn-doped Bi 3.15 Nd 0.85 Ti 3 O 12 (BNT), i.e., Bi 3.15 Nd 0.85 Ti 3 − x Mn x O 12 (BNTM, x = 0, 0.005, 0.01, 0.03, 0.05, and 0.1) thin films with bismuth-layered perovskite structure were prepared on Pt/Ti/SiO 2 /Si(100) substrates by a chemical solution deposition method at 700 °C. The crystal structures of BNTM films were analyzed by X-ray diffraction and the surface morphologies were observed by field emission scanning electron microscopy. The effects of Mn contents on the microstructures and dielectric properties of BNTM films are investigated in detail. Among these BNTM films, it is found that the BNTM01 ( x = 0.01) film exhibits the highest dielectric tunability and dielectric constant but the lowest dielectric loss. Compared with BNT film, the BNTM01 film has lower leakage current density. Eventually, the mechanism involved in the Mn doping effect on the electrical properties of the BNT films is discussed.

The effects of moderate annealing temperature (600–800 °C) on the microstructure, fatigue endurance, retention characteristic, and remnant polarization (2 P r ) of Bi 3.25 Eu 0.75 Ti 3 O 12 (BET) thin films prepared by metal-organic decomposition (MOD) were studied in detail. 2 P r (66 µC/cm 2 under 300 kV/cm), fatigue endurance (3% loss of 2 P r after 1.2 × 10 10 switching cycles), and retention characteristic (no significant polarization loss after 1.8 × 10 5 s) for BET thin film annealed at 700 °C are better than those for thin films annealed at other temperature. The mechanisms concerning the dependence of microstructure and ferroelectric properties on the annealing temperature were discussed.

Double-layered magnetoelectric thin films composed of Bi 3.15 Nd 0.85 Ti 3 O 12 (BNT) and CoFe 2 O 4 (CFO) were fabricated on Pt/Ti/SiO 2 /Si(1 0 0) substrates by chemical solution deposition with different growth sequences of BNT and CFO yielding the following layered structures: BNT/CFO/substrate (BC) and CFO/BNT/substrate (CB). X-ray diffraction results reveal that there are no other impurity phases but BNT and CFO phases in both BC and CB thin films. Scanning electron microscopy observation shows BNT layer is more compact than CFO layer in the films. These double-layered films exhibit both good ferroelectric and magnetic properties, as well as magnetoelectric effects at room temperature. The layer sequences have a great effect on the magnetoelectric coupling behavior of these double-layered thin films, which may be caused by the interface bonding of BNT and CFO.

The effects of CoFe2O4 content on the microstructure, leakage current density, fatigue endurance and magnetoelectric (ME) voltage coefficient of multiferroic Bi3.15Nd0.85Ti3O12–CoFe2O4 thin films fabricated by a chemical solution deposition method were studied. It was found that the composite films have lower leakage current densities and better fatigue endurance properties compared with pure Bi3.15Nd0.85Ti3O12 film, and the composite films possess large ME voltage coefficients. The mechanism concerning the dependence of properties on CoFe2O4 content is discussed.

BACKGROUND AND PURPOSE: Aneurysm recurrence is an innate problem after coiling, and the recurrence rate is higher in complicated aneurysms. We evaluated the feasibility and efficacy of using the Willis covered stent in treating recurrent aneurysms after coil embolization. MATERIALS AND METHODS: Eight aneurysms in 8 patients treated with detachable coils had confirmed recurrent aneurysms: 3 giant, 1 large, 1 dissecting, and 3 small wide-necked. The recurrent aneurysms involved C3 in 1 patient, C4 in 1, C7 in 5, and V4 in 1. A total of 11 covered stents were implanted into 8 target arteries. Follow-up angiography was performed 1–16 months after the procedure. Clinical follow-up data were collected and retrospectively analyzed, grading as fully recovered, improved, unchanged, or aggravated. RESULTS: Willis covered stent placement succeeded technically in all of the aneurysms. No technique-related adverse event occurred. Total occlusion was achieved immediately in 6 aneurysms, and a small endoleak was observed in 2 aneurysms. No mortality or morbidity occurred during or after the procedures, including during the follow-up period. Follow-up angiograms revealed that all 8 of the recurrent aneurysms were completely isolated, and 8 parent vessels kept patency, except 1 with mild stenosis. Clinical neurologic symptoms fully resolved in 5 patients, improved in 1, and were unchanged in 2 at the end of the follow-up period. CONCLUSIONS: In this small study with a middle-term follow-up, the Willis covered stent was used safely and effectively to occlude recurred aneurysms after coiling. Longer-term follow-up and additional clinical experience are needed to fully determine the safety and efficacy of the device.

Electroluminescence refrigeration in light emitting diodes is studied by taking into account carrier transport, carrier recombination, and influence of the dimensionality of electronic density of states (DOS) in active region. The cooling process happens when carriers transport from the metal contacts to the barrier layers. For a given bias voltage, the cooling power density decreases monotonically with the dimension of the DOS and increases as the carrier effective masses increases.

The injection and temperature dependence of the spontaneous emission quantum efficiency of molecular beam epitaxy grown GaAs/AlGaAs heterostructures is determined using excitation dependent photoluminescence (PL) measurements. Two samples are compared; one grown with Sb as a surfactant and one grown without Sb. The PL measurements were performed at temperatures from 80 to 320 K using a HeNe pump laser with powers ranging from 0.6 to 35 mW. The quantum efficiency is inferred from the power law predicted by the rate equations that links pump power and integrated PL signal. The use of Sb as surfactant improved the extrapolated peak spontaneous emission quantum efficiency from 0.970 to 0.977 at 300 K and from 0.996 to 0.998 at 180 K. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The electronic structure and the bonding mechanism of ZnO have been studied by using the Full-Potential Linear Augmented Plane Wave (FP-LAPW) method within the density-functional theory (DFT) based on LDA + U exchange correlation potential. The valence and the bonding charge density are calculated and compared with those derived from LDA and GGA to describe the bonding mechanism. The charge transfer along with the bonding process is analyzed by using the theory of Atoms in Molecules (AIM). The bonding, the topological characteristics and the p–d coupling effects on the bonding mechanism of ZnO are shown quantitatively with the critical points (CPs) along the bonding trajectory and the charge in the atomic basins. Meanwhile, the bonding characteristics for wurtzite, zinc blende and rocksalt phase of ZnO are discussed systematically in the present paper.

Nd-substituted bismuth titanate (Bi 3.15 Nd 0.85 Ti 3 O 12 , BNT) nanofibers were synthesized by electrospinning method utilizing a solution that contained poly(vinylpyrrolidone) (PVP) and sol–gel precursor solution of BNT. The BNT/PVP composite fibers were calcined in air for 1 h at 500, 600, 700, 750, and 800 ∘ C , respectively. Scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy were used to characterize the as-synthesized and calcined BNT/PVP composite nanofibers. The experimental results showed that the diameter, morphology, and crystallization of the nanofibers are influenced by the calcination temperature. After calcination at 700 ∘ C , BNT fibers are fully crystallized and exhibit a polycrystalline bismuth-layered perovskite structure, with a diameter of 70–160 nm and a length of over 6 μ m .

The study of the light emission in semiconductors using energy and entropy balance equations reveals that there is an intrinsic entropy generation built into the emission process. Such an irreversible property provides insight into the conversion of electrical energy into light. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

This paper reports a study of the photon recycling effect in semiconductor quantum well (QW) lasers and how to enhance such an effect to reduce threshold current density and to increase power conversion (wall-plug) efficiency. To maximize the enhancement of the spontaneous emission recycling, it is necessary to use metal contacts with high reflectivity, to remove the substrate, and to optimize the overall doping profile design. The modeling results have also shown that the threshold current density in a multiple quantum well laser has a weak dependence on the number of QWs when the photon recycling effect is strong. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The loop gain profile of the DC/DC converter is affected by the loading effect of the other DC/DC converters in the parallel DC/DC converter system. As a result, the control performance of the paralleled DC/DC converters system might be deteriorated due to parallel impedance interference. In order to investigate the effect of the parallel impedance interference, the dynamic model of the parallel DC/DC converter system was build up via a general dynamic circuit scheme. From the analysis results, the impedance interference can be identified clearly. Some simulations and experimental results will provide to validate the aforementioned findings.

Pulsar timing arrays (PTAs) can be used to search for very low frequency ($10^{-9}$--$10^{-7}$ Hz) gravitational waves (GWs). In this paper we present a general method for the detection and localization of single-source GWs using PTAs. We demonstrate the effectiveness of this new method for three types of signals: monochromatic waves as expected from individual supermassive binary black holes in circular orbits, GWs from eccentric binaries and GW bursts. We also test its implementation in realistic data sets that include effects such as uneven sampling and heterogeneous data spans and measurement precision. It is shown that our method, which works in the frequency domain, performs as well as published time-domain methods. In particular, we find it equivalent to the $\mathcal{F}_{e}$-statistic for monochromatic waves. We also discuss the construction of null streams -- data streams that have null response to GWs, and the prospect of using null streams as a consistency check in the case of detected GW signals. Finally, we present sensitivities to individual supermassive binary black holes in eccentric orbits. We find that a monochromatic search that is designed for circular binaries can efficiently detect eccentric binaries with both high and low eccentricities, while a harmonic summing technique provides greater sensitivities only for binaries with moderate eccentricities., Comment: To match the published version, 17 pages, 13 figures

Bi 3.25 La 0.75 Ti 3 O 12 (BLT) thin films were fabricated on Pt/Ti/SiO 2 /Si(1 0 0) substrates by chemical solution deposition (CSD), and the dependence of ferroelectric and dielectric properties of the as-deposited BLT thin films on excess Bi content in precursor sols was studied. It is found that the prepared BLT thin film shows the best polarization–electric field, capacitance–voltage and dielectric constant ( ɛ r )–frequency characteristics, when the value of excess Bi content in precursor sols is 10%. In detail, its remnant polarization (2 P r ) value is 40 μC/cm 2 , the capacitance tunability is 21% measured at room temperature under conditions of an applied voltage of 8 V and measurement frequency of 10 kHz, and the ɛ r is 696 at 100 kHz frequency.

This paper provides data on weathering properties and reduction factors for two geotextiles in ocean environments. The study included outdoor ultraviolet (UV) exposure tests performed at the Harbor and Marine Technology Research Center in Taiwan using a black polypropylene and a white polyester geotextile. Ultraviolet exposure was the most significant factor in reducing the strength properties of the geotextiles tested in an ocean environment. Seawater immersion had the least weathering effect on the engineering properties of the test geotextiles among the test conditions. The effect on engineering properties of placing samples within the tidal zone was slightly higher than that for the immersion condition. Reduction factors for UV exposure and seawater weathering for the test geotextiles are reported.

This paper considers the general, no-wait and no-idle flow shop scheduling problems with deteriorating jobs. By a deteriorating job we mean that the processing time is an increasing function of its execution starting time. A linear deterioration function is assumed and some dominating relationships between machines can be satisfied. It is shown that for the problems to minimize the makespan or the weighted sum of completion time, polynomial algorithms still exist, although these problems are more complicated than the classical ones. When the objective is to minimize the maximum lateness, the solutions of a classical version may not hold.

Summary Two molecular genetic screening techniques, RAPD (random amplified polymorphic DNAs) and ISSR (inter-simple sequence repeats), were applied to detect the level and pattern of genetic diversity of Monochoria vaginalis, a common weed of rice fields, in seven populations from southern China. Among these populations, 116 bands were amplified by 18 RAPD primers, of which 34 bands (29.31%) were polymorphic, and 14 ISSR primers produced 111 bands with 87 polymorphic bands (78.38%). Within each population, a relatively low level of genetic diversity was detected by both RAPD and ISSR analyses, with a mean genetic diversity (H) of 0.0348 and 0.0551 respectively. Analysis of molecular variance of the data from the RAPD and ISSR markers detected that the majority of total genetic variation existed among populations (73.50% and 76.70% respectively) and only minor genetic variation within populations (26.50% and 23.30% respectively). Cluster analysis divided the seven populations into two groups, indicating that the genetic relationships among populations have relatively low correlation with their geographical distribution (Mantel test; r = 0.45 and 0.48 respectively). Our results indicated that both RAPD and ISSR markers were effective and reliable for accurately assessing the degree of genetic variation of M. vaginalis. Comparing the two techniques, ISSR markers were more efficient than the RAPD assay. The Mantel test gave r = 0.16, suggesting no correlation between these two molecular markers.

The paper is devoted to some flow-shop scheduling problems with a learning effect. The objective is to minimize one of the two regular performance criteria, namely, makespan and total flowtime. A heuristic algorithm with worst-case bound m for each criteria is given, where m is the number of machines. Furthermore, a polynomial algorithm is proposed for both of the special cases: identical processing time on each machine and an increasing series of dominating machines. An example is also constructed to show that the classical Johnson's rule is not the optimal solution for the two-machine flow-shop scheduling to minimize makespan with a learning effect. Some extensions of the problem are also shown.

Nd-substituted Bi 4 Ti 3 O 12 (BNT) ferroelectric thin films have been fabricated on Pt/Ti/SiO 2 /Si(1 0 0) substrates by chemical solution deposition (CSD). X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to identify the crystal structure, the surface and cross-section morphology of the deposited ferroelectric films. After annealing at 700 °C, the Bi 3.15 Nd 0.85 Ti 3 O 12 and Bi 3.54 Nd 0.46 Ti 3 O 12 films are crystallized and exhibit a polycrystalline structure, but however show different preferred orientations. The experimental results show the ferroelectric and dielectric properties of the Bi 3.15 Nd 0.85 Ti 3 O 12 thin films are better than those of Bi 3.54 Nd 0.46 Ti 3 O 12 thin films. Bi 3.15 Nd 0.85 Ti 3 O 12 thin films show a large remanent polarization (2 P r ) of 65.4 μC/cm 2 under a maximum applied field of 356 kV/cm and high dielectric constant ( e r ) of 521 at the frequency of 10 kHz. This work clearly reveals that Bi 3.15 Nd 0.85 Ti 3 O 12 thin film has the more promising potential application in the non-volatile ferroelectric random access memories and dynamic random access memories.

Infrared (IR) reflection spectra of GaN1−xPx alloys, grown by light-radiation heating, low-pressure metalorganic chemical vapor deposition, have been investigated with phosphorus composition x=0–0.15. A multi-oscillator model has been used to fit the IR reflection spectra. In addition to the demonstration of a GaN-like transverse-optical (TO) mode, a GaP-like TO mode, located at about 355cm−1, has been identified for x>0, showing a typical two-mode behavior. With the increment of x the frequency of the GaN-like TO phonon decreases and the GaP-like TO phonon keeps its frequency almost unchanged within the measured composition range. A simple random-element-isodisplacement model has been employed to interpret the frequency change of both GaN-like and GaP-like phonons with the phosphorous composition x. The damping of the GaN-like TO mode increases significantly with x and is explained by the disorder effect resulting from the introduction of foreign P atoms.

The GaAsSb/GaAs conduction band alignment is determined to be almost flat (weak type-I) in the 0.3 Sb mole fraction neighborhood where 1300 nm emission is observed. Based on photoluminescence measurements and modeling the bandgap bowing parameter of pseudomorphic GaAsSb on GaAs is determined to be −2.0 eV with the bowing distributed 45% to the conduction band. Using these parameters the GaAsSb band edge energies are determined over the 0.0 to 0.5 Sb mole fraction range. The effect of band alignment on electron–hole overlap and wavelength extension is discussed.

Pulsar timing observations are being carried out with the Nanshan 25-metre radio telescope since 2000. We observe about 300 pulsars, including nine millisecond pulsars, at 1.5 GHz with a cryogenic receiver and digital filterbank. Frequent observations at Nanshan revealed 50 glitches. We detect nine more glitches in the past two years. Timing solutions obtained with the Nanshan telescope for eight radio loud Gamma ray pulsars are presented.

Gravitational wave bursts produced by supermassive binary black hole mergers will leave a persistent imprint on the space-time metric. Such gravitational wave memory signals are detectable by pulsar timing arrays as a glitch event that would seem to occur simultaneously for all pulsars. In this paper, we describe an initial algorithm which can be used to search for gravitational wave memory signals. We apply this algorithm to the Parkes Pulsar Timing Array data set. No significant gravitational wave memory signal is founded in the data set., Comment: Proceedings of IAUS 291 "Neutron Stars and Pulsars: Challenges and Opportunities after 80 years", J. van Leeuwen (ed.); 3 pages, no figure

Co-doped ZnO nanorods were fabricated by a chemical vapor deposition method, and their structural and magnetic properties were investigated. After annealing under various conditions, these nanorods show ferromagnetic rather than paramagnetic behavior. Extended X-ray absorption fine structure analysis suggests that the room temperature ferromagnetism of Co-doped ZnO nanorods results from Co 2+ –Co 2+ ferromagnetic coupling.