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Under unstable wind loads, the wind turbine tower, as a supporting component of the horizontal axis experiences inevitable vibration. To explore the vibration characteristics of the tower, a vehicle test platform is established to measure the vibration acceleration component signals at different heights of a 300W small horizontal axis wind turbine tower. The results show that specific vehicle vibration test equipment can accurately test the vibration characteristics and laws of small wind turbine towers. The main vibration form of the tower is low frequency, with noticeable axial vibration at the top and lateral vibration in the middle of the tower due to aerodynamic load from natural wind. These findings can be used as a valuable reference for the safety and reliability design of the whole machine and the low-frequency vibration status monitoring of wind turbines. [ABSTRACT FROM AUTHOR]

Anthocyanins and selenium (Se) have antioxidant properties and are crucial to human health. Previous works have well studied the role of exogenous Se fertilization in grain quality and anthocyanin formation in colored crops, whereas few reports on naturally Se-enriched colored grains exist. In this study, the quality, anthocyanin accumulation, and metabolism of natural Se-enriched purple waxy corn and common purple waxy corn were compared during kernel development. Natural Se-enriched purple waxy corn had higher concentrations of total Se, anthocyanins, flavones, starch (branched- and straight-chain), and sugar than common purple waxy corn, and the optimum eating date was 28 days after pollination. Genes related to anthocyanin biosynthesis were significantly upregulated in natural Se-enriched purple waxy corn, resulting in enriched anthocyanin metabolites (6-O-malonyl-beta-D-glu and 3-O-glu in Cy, Pn, and Pg). Most importantly, genetic alterations were observed which several genes and transcription factors were downregulated some branch pathways of lignin synthesis and accelerated anthocyanin synthesis. Our results profiled anthocyanin metabolism in naturally Se-enriched purple waxy corn to promote harvesting. [ABSTRACT FROM AUTHOR]

By means of microstructure observation, microhardness, tensile and rotating bending fatigue tests, the effects of austempering treatment on the formation of lower bainite, carbide precipitation and mechanical properties of M50NiL bearing steel were studied. Results showed that multi-layer composite microstructure was formed in the steel after austempering treatment. The microstructure of the surface layer was mainly consisted of lower bainite, martensite and carbides, that of the sub-surface layer contained granular carbides, a little lower bainite, lath martensite, twin martensite and thin film retained austenite, and that of the core region mostly contained lath martensite. In contrast with the traditional martensite quenching treatment, there was more lower bainite formed in the surface layer after austempering treatment. The appearance of acicular bainite dramatically decreased the effective grain size by refining the microstructure, and there were more finer carbides precipitated in the lath martensite. After austempering treatment and tempering, the average hardness in surface layer of the steel increased from 746.5 HV0.5 to 786.4 HV0.5, and the rotating bending fatigue limit of the steel increased from 870.9 to 1170.0 MPa, but the tensile strength of the steel decreased slightly. The effects of austempering treatment on the mechanical properties had a close relationship with the carbide precipitation behavior and the formation of lower bainite. [ABSTRACT FROM AUTHOR]

The great demographic pressure brings tremendous volume of beef demand. The key to solve this problem is the growth and development of Chinese cattle. In order to find molecular markers conducive to the growth and development of Chinese cattle, sequencing was used to determine the position of copy number variations (CNVs), bioinformatics analysis was used to predict the function of ZNF146 gene, real-time fluorescent quantitative polymerase chain reaction (qPCR) was used for CNV genotyping and one-way analysis of variance was used for association analysis. The results showed that there exists CNV in Chr 18: 47225201-47229600 (5.0.1 version) of ZNF146 gene through the early sequencing results in the laboratory and predicted ZNF146 gene was expressed in liver, skeletal muscle and breast cells, and was amplified or overexpressed in pancreatic cancer, which promoted the development of tumour through bioinformatics. Therefore, it is predicted that ZNF146 gene affects the proliferation of muscle cells, and then affects the growth and development of cattle. Furthermore, CNV genotyping of ZNF146 gene was three types (deletion type, normal type and duplication type) by Real-time fluorescent quantitative PCR (qPCR). The association analysis results showed that ZNF146 -CNV was significantly correlated with rump length of Qinchuan cattle, hucklebone width of Jiaxian red cattle and heart girth of Yunling cattle. From the above results, ZNF146 -CNV had a significant effect on growth traits, which provided an important candidate molecular marker for growth and development of Chinese cattle. [ABSTRACT FROM AUTHOR]

Plasma position and shape parameters are essential for equilibrium control and physics analysis in a tokamak. Such information is often obtained via optical boundary analysis. In this study, a new analysis of the visible image histogram of a high-speed high-resolution camera is presented which can effectively distinguish between the foreground information (showing the plasma of interest) and the background information (showing the inside views of the vacuum vessel wall and flanges, and so on). Using this method, we can obtain a reasonable approximation to the plasma boundary close to the last closed flux surface (LCFS) where plasma brightness contrast is greatest. The reliability and accuracy of this method are checked by comparing it favorably with other algorithms for different plasma shapes. The method is successfully tested also when the outboard plasma boundary oscillates in time with a magnitude of 10%. [ABSTRACT FROM AUTHOR]

Understanding tourists' perceptions of climate is essential to improving tourist satisfaction and destination marketing. This paper constructs a sentiment analysis framework for tourists' perceptions of climate using not only continuous climate data but also short-term weather data. Based on Chinese social media platform Sina Weibo, we found that Chinese tourists' perceptions of climate change were at an initial stage of development. The accuracies of word segmentation between sentiment and nonsentiment words using ROST content mining (CM), BosonNLP, and GooSeeker were all high, and the three gradually decreased. The positively expressed sentences accounted for 79.80% of the entire text using ROST emotion analysis (EA), and the sentiment score was 0.784 at the intermediate level using artificial neural networks. The results indicate that the perceived emotional map is generally consistent with the actual climate and that cognitive evaluation theory is suitable to study text on climate perception. [ABSTRACT FROM AUTHOR]

High-performance ultraviolet (UV) detectors with both high responses and fast speeds are hard to make on homogeneous crystal semiconductor materials. Here, the UV response characteristics of mixed-phase MgZnO thin films with different internal structure distributions are studied. The mixed-phase MgZnO-based detector with the given crystal composition has a high response at both deep UV light (96 A W−1 at 240 nm) and near UV light (80 A W−1 at 335 nm). Meanwhile, because of the quasi-tunneling breakdown mechanism within the device, the high-response UV detector also shows a fast response speed (tr = 0.11 μs) and recovery speed (td1 = 26 μs) at deep UV light, which is much faster than both low-response mixed-phase MgZnO-based UV detectors with other structure constitutions and reported high-response UV devices on homogenous crystal materials. The Idark of the device is just 4.27 pA under a 5 V bias voltage, so the signal-to-noise ratio of the device reached 23852 at 5.5 uW cm−2 235 nm UV light. The new quasi-tunneling breakdown mechanism is observed in some mixed-phase MgZnO thin films that contain both c-MgZnO and h-MgZnO parts, which introduce a high response, signal-to-noise ratio, and fast speed into mixed-phase MgZnO-based UV detectors at weak deep UV light. [ABSTRACT FROM AUTHOR]

Pixelated scintillators arrays are widely used in X-ray radiographic applications and provide the sensitivity and resolution of detectors, which are determined by the pixel size and thickness. The design of pixelated scintillator arrays is impeded by the absence of a suitable method to simulate and predict the performance. A method of design and optimization based on a Monte Carlo simulation of a pixelated lutetium yttrium oxyorthosilicate scintillator array for MeV X-ray flash radiography has been established. The variance of the gain and spatial resolution of scintillators with different structural parameters have been studied. The proposed method was subsequently validated using flash radiographic experiments. The results of both agree well. Furthermore, the results indicate that an array with a large pixel size and small thickness exhibits strong scintillator gain, sufficient spatial resolution, and excellent uniformity of response. [ABSTRACT FROM AUTHOR]

Background: Sexual transmission chains of Ebola virus (EBOV) have been verified and linked to EBOV RNA persistence in semen, post-recovery. The rate of semen persistence over time, including the average duration of persistence among Ebola virus disease (EVD) survivors, is not well known. This cohort study aimed to analyze population estimates of EBOV RNA persistence rates in semen over time, and associated risk factors in a population of survivors from Sierra Leone.Methods and Findings: In this cohort study from May 2015 to April 2017 in Sierra Leone, recruitment was conducted in 2 phases; the first enrolled 100 male participants from the Western Area District in the capital of Freetown, and the second enrolled 120 men from the Western Area District and from Lungi, Port Loko District. Mean age of participants was 31 years. The men provided semen for testing, analyzed by quantitative reverse transcription PCR (qRT-PCR) for the presence of EBOV RNA. Follow-up occurred every 2 weeks until the endpoint, defined as 2 consecutive negative qRT-PCR results of semen specimen testing for EBOV RNA. Participants were matched with the Sierra Leone EVD case database to retrieve cycle threshold (Ct) values from the qRT-PCR analysis done in blood during acute disease. A purposive sampling strategy was used, and the included sample composition was compared to the national EVD survivor database to understand deviations from the general male survivor population. At 180 days (6 months) after Ebola treatment unit (ETU) discharge, the EBOV RNA semen positive rate was 75.4% (95% CI 66.9%-82.0%). The median persistence duration was 204 days, with 50% of men having cleared their semen of EBOV RNA after this time. At 270 days, persistence was 26.8% (95% CI 20.0%-34.2%), and at 360 days, 6.0% (95% CI 3.1%-10.2%). Longer persistence was significantly associated with severe acute disease, with probability of persistence in this population at 1 year at 10.1% (95% CI 4.6%-19.8%) compared to the probability approaching 0% for those with mild acute disease. Age showed a dose-response pattern, where the youngest men (≤25 years) were 3.17 (95% CI 1.60, 6.29) times more likely to be EBOV RNA negative in semen, and men aged 26-35 years were 1.85 (95% CI 1.04, 3.28) times more likely to be negative, than men aged >35 years. Among participants with both severe acute EVD and a higher age (>35 years), persistence remained above 20% (95% CI 6.0%-50.6%) at 1 year. Uptake of safe sex recommendations 3 months after ETU discharge was low among a third of survivors. The sample was largely representative of male survivors in Sierra Leone. A limitation of this study is the lack of knowledge about infectiousness.Conclusions: In this study we observed that EBOV RNA persistence in semen was a frequent phenomenon, with high population rates over time. This finding will inform forthcoming updated recommendations on risk reduction strategies relating to sexual transmission of EBOV. Our findings support implementation of a semen testing program as part of epidemic preparedness and response. Further, the results will enable planning of the magnitude of testing and targeted counseling needs over time. [ABSTRACT FROM AUTHOR]

Pores can easily form in the geometric center and sharp corner lap joints of solid components with polygonal cross-sections fabricated by wire and arc additive manufacturing. To solve these problems, this paper proposes a composite path planning method and a sharp corner correction strategy. The composite path planning method consists of the zigzag path and the contour offsetting path. The zigzag path is used to fill the interior of the component and eliminates pores formed by traditional filling paths. The contour offset path is used to improve the geometric precision of the component. Filling paths are connected to create a closed path, which reduces arc striking and arc extinguishing during the manufacturing process. By exploring the distance between two vertices of a sharp corner lap of the outer contour path, it was found that pores form in the sharp corner lap when the angle of the sharp corner is less than 58.65°; therefore, the sharp corner correction strategy is proposed to correct the sharp corner lap path in the outer contour path. Experimental results show that the composite path filling method and the sharp corner correction strategy can eliminate pores between the geometric center and the sharp corner lap joints of components, thereby improving surface morphology and forming quality of components with complex polygonal cross-sections. [ABSTRACT FROM AUTHOR]

The highly (l00) oriented Pb(Zr0.5Ti0.5)O3 thin films with different Fe3+ doping concentrations were fabricated on LaNiO3-coated silicon substrates by chemical solution deposition. And the microstructure, ferroelectric, leakage, and magnetic properties were investigated. The results indicate that incorporation of Fe3+ into PZT thin films can promote the degree of the lattice distortion and greatly improve the surface roughness. In comparison with the pure PZT sample, the ferroelectric hysteresis loops of Fe-doped PZT samples demonstrate larger and larger polarizations and coercive fields with the increase in Fe3+ doping amount. Moreover, leakage mechanism of present films evolves from the space charge limited conduction to the “modified” space charge limited conduction, and then returns to the space charge limited conduction with increasing Fe3+ doping concentration. The occurrence of exchange bias in these Fe-doped PZT samples implies that the magnetic exchange interaction can be explained by the bound magnetic polaron model. [ABSTRACT FROM AUTHOR]

A uniform diamond nanocone array was formed by plasma etching of diamond film in a hot filament chemical vapor deposition (HFCVD) system. A surface amorphous carbon coating layer, which is formed during CH4/H2 plasma-etching process, was removed by Ar plasma in a reactive ion etching system. The hydrogenation of diamond nanocones was performed in H2 ambience by using the same HFCVD system. The air-diluted NH3 and NO2 gases sensing properties of the diamond cone arrays had been studied by using electric current versus measurement time characteristics at room temperature. The repeatable chemical sensing properties of the hydrogenated diamond cone array sensor are enhanced, in comparison with as-formed diamond film. Surface two-dimensional hole gas structure and greatly increased surface-to-volume ratio both play a key role for the excellent detection performance. As-formed diamond nanocone arrays show a promising prospect for applications as chemical sensor for both reducing (NH3) and oxidizing (NO2) gases. [ABSTRACT FROM AUTHOR]

This work aims to construct accurate and simple lower-order analytical approximation solutions for the free and forced vibration of electrostatically actuated micro-electro-mechanical system (MEMS) resonators, in which geometrical and material nonlinearities are induced by the mid-plane stretching, dynamic pull-in characteristics, electrostatic forces and other intrinsic properties. Due to the complexity of nonlinear MEMS systems, the quest of exact closed-form solutions for these problems is hardly obtained for system design and analysis, in particular for harmonically forced nonlinear systems. To examine the simplicity and effectiveness of the present analytical solutions, two illustrative cases are taken into consideration. First, the free vibration of a doubly clamped microbeam suspended on an electrode due to a suddenly applied DC voltage is considered. Based on the Euler–Bernoulli beam theory and the von Karman type nonlinear kinematics, the dynamic motion of the microbeam is further discretized by the Galerkin method to an autonomous system with general nonlinearity, which can be solved analytically by using the Newton harmonic balance method. In addition to large-amplitude free vibration, the primary resonance response of a doubly clamped microbeam driven by two symmetric electrodes is also investigated, in which the microbeam is actuated by a bias DC voltage and a harmonic AC voltage. Following the same decomposition approach, the governing equation of a harmonically forced beam model can be transformed to a nonautonomous system with odd nonlinearity only. Then, lower-order analytical approximation solutions are derived to analyze the steady-state resonance response of such a problem under a combination of various DC and AC voltage effects. Finally, the analytical approximation results of both cases are validated, and they are in good agreement with those obtained by the standard Runge–Kutta method. [ABSTRACT FROM AUTHOR]

In this study, comparative corrosion protection studies of cold-rolled steel (CRS) electrodes coated with electroactive/non-electroactive epoxy thermoset (denoted as EET/NEET) composites containing dispersed reduced graphene oxide (rGO) and graphene oxide (GO) platelets are presented. All composites were obtained through the thermal ring-opening reaction of bisphenol A diglycidyl ether (DGEBA) with amino-capped aniline trimer (ACAT) or trimethylolpropane tris[poly(propylene glycol), amine terminated] ether (T-403) at a specific mixing ratio in the presence of dispersed rGO/GO were characterized Fourier Transform Infrared (FTIR) spectroscopy and Transmission Electron Microscopy (TEM). In gas permeability measurements, the GO was found to display a slightly better dispersion capability in both EET and NEET membrane than in rGO. Conductive rGO platelets were found to promote the redox behavior of EET and non-conductive GO platelets was found to depress the redox behavior of EET, as measured by electrochemical cyclic voltammetry (CV) studies. Corrosion protection of composite coatings was investigated by electrochemical corrosion measurements in saline solution. It should be noted, in the EET system, that rGO was found to exhibit better anticorrosion performance as compared to that of GO. However, in NEET system, GO was found to have better anticorrosion performance than rGO. Better anticorrosion of rGO in EET may be attributed to better synergistic effect of electro-catalytic and the oxygen barrier properties of rGO in EET. On the contrary, better anticorrosion of GO in NEET may be associated with better oxygen barrier property of GO alone in NEET than that of rGO. The passive metal oxide layer formed on the cold rolled steel (CRS) electrode induced by EET was further confirmed by Raman and Electron Spectroscopy for Chemical Analysis (ESCA). [ABSTRACT FROM AUTHOR]

To improve the electrical performance of thin-film transistors with an atomic-layer-deposited Al2O3 dielectric/InOx channel, O2 plasma surface treatments of the InOx back channel are explored in comparison with thermal annealing. It is demonstrated that the O2 plasma treatment can enhance the device performance much more efficiently than thermal annealing, exhibiting an extremely low-thermal budget. Furthermore, it is revealed that the plasma treatment at a higher temperature can improve the device performance much faster than that at a lower temperature. For a 4 min O2plasma treatment at 200 °C, superior electrical characteristics are achieved, such as a field-effect mobility of 11 cm2V−1s−1, a threshold voltage of 0.9 V, a subthreshold swing of 0.38 V/dec, and good gate bias stress stabilities. This is ascribed to faster passivation of oxygen vacancies, removal of more C residues, and weaker surface damage and smaller surface roughness of the InOx back channel in comparison with long plasma treatments at lower temperatures. [ABSTRACT FROM AUTHOR]

In the process of micro beam plasma welding of thin-walled parts, gravity and surface tension make a molten metal flow downward, sometimes causing a bad formation. To solve this problem, a new external magnetic field-controlled method based on the eddy current principle was proposed. The distribution of the magnetic flux density, the induced current density, and the Lorentz force on a 4 mm stainless steel AISI 304 thin plate was examined using different oscillation frequencies (1, 5, 10 kHz) of the magnetic field with the finite element package COMSOL Multiphysics 5.0. The higher frequency was found to be more helpful to create greater electromagnetic force. This study examined the single-pass and three-layer welding of the 4-mm-thick stainless steel AISI 304 with different magnetic fields (3~12 mT) at 10 kHz. The results show that 7- and 8-mT magnetic fields were effective in suppressing the sagging of the cladding layer. [ABSTRACT FROM AUTHOR]

An efficient biosurfactant-producing strain was isolated and cultured from Dagang oil field (China) using crude oil as sole source of carbon. Based on partial sequenced 16S rDNA analysis, the isolated strain was identified as Pseudomonas aeruginosa SNP0614. The bacterium P. aeruginosa SNP0614 produced a type of biosurfactant with excessive foam-forming properties. After microbial cultivation at 37°C and 150 rpm for 12 h, the produced biosurfactant was found to reduce the surface tension to 25.4 mN/m with critical micelle concentration (CMC) of 45.0 mg/L. After 20 days of incubation, the biosurfactant exhibited 90% emulsification activity (E24) on crude oil. FTIR spectroscopy of extracted biosurfactant indicated the biosurfactant as lipopeptide. The significant synergistic effect between P. aeruginosa SNP0614 and the mixed oildegrading bacteria resulted in increasing n-alkanes degradation rate by 30%. The strain P. aeruginosa SNP0614 represented as a promising biosurfactant producer and could be applied in a variety of biotechnological and industrial processes, particularly in microbial enhanced oil recovery and the bioremediation of oil pollution. [ABSTRACT FROM AUTHOR]

MgZnO thin films (with Mg0.4Zn0.6O as the target) were fabricated on fused quartz substrates employing PLD method under different laser energy densities. Cubic structured MgZnO thin films were made at laser energy densities of 20 J cm−2 and 22 J cm−2, whilst the MgZnO thin films were deposited along both cubic and hexagonal structures under higher laser energy density condition. When a higher energy density laser was focused on the MgZnO target during the deposition process, the MgZnO thin film was found to be deposited with a more hexagonal structure and a higher Zn composition. There are two response peaks located in the solar-blind UV and visible-blind UV regions within the UV response spectrum of the mixed-phase MgZnO based detector deposited at laser energy over 24 J cm−2. When the deposition laser energy density increased from 24 to 30 J cm−2, the maximum UV responsivity of the mixed-phase MgZnO-based detector increased from 0.06 A W−1 to 1 A W−1 at 40 V bias voltage, and the visible-blind UV response peak of the mix-phase MgZnO based detector was also higher due to the MgZnO adopting a more hexagonal structure; furthermore, a higher internal gain is obtained, which can be attributed to a higher density of interfaces between the MgZnO grains of different structures in the mixed-phase MgZnO thin film. At 5 V bias voltage, the Ilight(230 nm)/Idark ratio of the UV detector based on mix-phase MgZnO deposited at 24 J cm−2 reached 500, and the Ilight(290 nm)/Idark ratio of the UV detector based on mix-phase MgZnO deposited at 26 J cm−2 reached 1100. Therefore, the UV-detector based on mixed-phase MgZnO thin films is sensitive to solar-blind and visible-blind UV light with strong background noise (on Earth) when the boundaries between (111) an (200) cubic MgZnO makes obvious function in decreasing the dark current of the detectors at lower bias voltage. [ABSTRACT FROM AUTHOR]

Ureido-pyrimidone (Upy) can dimerize in a self-complementary array of quadruple hydrogen bonds. In this paper, supramolecular polymer composites were prepared by blending Upy functionalized nanosilica with Upy end-capped polycarbonatediol. Surface characteristics of Upy functionalized nanosilica and influences of supramolecular forces on interfacial binding were researched. Fourier transform infrared spectroscopy (FTIR), Nuclear magnetic resonance (NMR) and Gel permeation chromatography (GPC) were used to characterize the synthesized molecules. Grafting ratio of Upy segments on the surface of nanosilica was analysed by Thermogravimetic analysis (TGA). Hydrophobicity and morphology of Upy modified nanosilica were analysed by Contact angle tester and Scanning electron microscope (SEM). Furthermore, dynamic thermo mechanical properties, mechanical properties and distribution of nanosilica in supramolecular polymer composites were also researched. Compared with the matrix resin, tensile stress and young's modulus of supramolecular polymer composites containing 5 wt% modified nanosilica were increased by 292 and 198% respectively. [ABSTRACT FROM AUTHOR]

H-related defects have been investigated in Ga-doped ZnO thin films deposited by RF magnetron sputtering at room temperature in Ar+H2ambient. When the flow ratio of H2/(Ar+H2) increases from 0 to 4%, the resistivity significantly decreases from 1·94 × 10−2to 5·69 × 10−4 Ω cm. X-ray diffraction and X-ray photoelectron spectroscopy results show that it should not be ascribed to the films’ crystalline quality, the chemical states and substitutional situation of Ga and Zn. It is suggested that there are a large number of acceptors in the films, the major role of H is to passivate the acceptors but H-donors themselves do not play a significant role. These acceptor-like defects are located at grain boundaries (dangling bonds) and in bulk (VZnand/or GaZn–VZn). Post-growth annealing experiment and optical transmittance results exhibit that the passivated acceptors are mainly at grain boundaries rather than in bulk. [ABSTRACT FROM PUBLISHER]

Benzene is a common occupational hazard and a widespread environmental pollutant. Previous studies have revealed that 72 h exposure to benzene metabolites inhibited hemin-induced erythroid differentiation of K562 cells accompanied with elevated methylation in erythroid specific genes. However, little is known about the effects of long-term and low-dose benzene metabolite exposure. In this study, to elucidate the effects of long-term benzene metabolite exposure on erythroid differentiation, K562 cells were treated with low-concentration phenol, hydroquinone and 1,2,4-benzenetriol for at least 3 weeks. After exposure of K562 cells to benzene metabolites, hemin-induced hemoglobin synthesis declined in a concentration- and time-dependent manner, and the hemin-induced expressions of α-, β- and γ-globin genes and heme synthesis enzyme porphobilinogen deaminase were significantly suppressed. Furthermore, when K562 cells were continuously cultured without benzene metabolites for another 20 days after exposure to benzene metabolites for 4 weeks, the decreased erythroid differentiation capabilities still remained stable in hydroquinone- and 1,2,4-benzenetriol-exposed cells, but showed a slow increase in phenol-exposed K562 cells. In addition, methyltransferase inhibitor 5-aza-2′-deoxycytidine significantly blocked benzene metabolites inhibiting hemoglobin synthesis and expression of erythroid genes. Quantitative MassARRAY methylation analysis also confirmed that the exposure to benzene metabolites increased DNA methylation levels at several CpG sites in several erythroid-specific genes and their far-upstream regulatory elements. These results demonstrated that long-term and low-dose exposure to benzene metabolites inhibited the hemin-induced erythroid differentiation of K562 cells, in which DNA methylation played a role through the suppression of erythroid specific genes. [ABSTRACT FROM AUTHOR]

An experimental method is developed for the purpose of simulating plutonium aerosol source terms with conventional metals in laboratory. In this method, metal samples are aerosolized by high explosive detonation in a containment vessel. Aerosols having aerodynamic diameter (AD) less than 10 µm are then collected by a cascade impactor and analyzed by atomic absorption spectroscopy. Two sets of experiments were conducted. In the first set, five candidate metal samples (Ag, W, Sn, Ce, and V) were tested. It is found that the cumulative mass distribution of silver under certain conditions was in good agreement with that of plutonium from the Operation Roller Coaster-Double Track experiment. Thus, silver is chosen as a surrogate to simulate the plutonium aerosol source term. In the second set, silver aerosol source term was studied in detail with different test configurations. The results demonstrate that the peak of the mass-size distribution of silver is in the AD range 1.1–3.3 µm. The amount and fraction of relatively small silver aerosols decrease significantly with time due to coagulation and deposition. Interestingly, the amount of silver in aerosols could be expressed as a quadratic function of the peak detonation pressure. © 2016 American Association for Aerosol Research [ABSTRACT FROM PUBLISHER]

To elucidate the effect of thyroid hormone receptor α A ( thraa) on metamorphosis, the full length cDNA of half-smooth tongue sole Cynoglossus semilaevis was cloned. The relative gene transcript level of thraa at different development stages was quantified using real-time PCR. Transcription of thraa increased and declined rapidly during metamorphosis. Hyperthyroidism was induced in juveniles and larvae with exposure to T3 and T4, and hypothyroidism with thiourea ( TU), 2-mercapto-1-methylimidazole ( MMI). thraa mRNA was higher in fish treated for 6 days with MMI than in untreated controls, although inhibited larvae did not complete metamorphosis. The addition of exogenous T4 reversed this effect in the MMI-treated group, but not in the TU-treated group. In situ hybridization revealed progressive tail end of body growth and change during developmental stages, with corresponding changes in thraa expression. This process may be induced by thyroid hormones with thraa as a major mediator. The morphological changes of tip of the tail may be associated with the development of lateral swimming. [ABSTRACT FROM AUTHOR]

We demonstrated a flash memory device with chemical-vapor-deposited graphene as a charge trapping layer. It was found that the average RMS roughness of block oxide on graphene storage layer can be significantly reduced from 5.9 nm to 0.5 nm by inserting a seed metal layer, which was verified by AFM measurements. The memory window is 5.6 V for a dual sweep of ±12 V at room temperature. Moreover, a reduced hysteresis at the low temperature was observed, indicative of water molecules or −OH groups between graphene and dielectric playing an important role in memory windows. [ABSTRACT FROM AUTHOR]

Factors affecting boron yield rate in liquid steel during the refining and continuous casting stages were analysed by industrial tests and thermodynamic calculations. The experimental results showed that boron could not react with the dissolved oxygen in the liquid steel above 1794 K because of the low oxygen levels. The inclusions containing boron were caused by secondary oxidation of the liquid steel. During refining and continuous casting stages, boron could not react with nitrogen and N2 when the actual content of boron in the liquid steel was 16 ppm. The main reason for boron loss is the secondary oxidation of the boron. So, taking effective measures against secondary oxidation of boron is an important method to improve the boron yield rate. The boron yield rate increases with the increase of acid-soluble aluminium in steel. Controlling the appropriate content of acid-soluble aluminium effectively prevents oxidation of the boron. Liquid steel secondary oxidation can be prevented by optimising the refining and Continuous Casting (CC) technology including by enhancing the seal protection of the liquid steel from the tundish to the mould. [ABSTRACT FROM AUTHOR]

The influence of alloying elements on the stacking fault energy (SFE) of magnesium alloys containing long period stacking ordered (LPSO) structure was studied systematically by means of first-principles calculation. The element features and criterion of formation of LPSO in Mg-RE-X system was discussed, when X = Zn, Cu, Ag and Cu, and RE = Gd, Dy, Ho, Er and La. It was found that stacking faults played a crucial role in formation of LPSO structure. The influence of SFE should be considered into the element features and criterion of the formation of LPSO. The element features and criterion of formation of LPSO in Mg-RE-X system were suggested to be modified as follows: the element RE and X can decrease the SFE of magnesium alloys and the algebraic expression for the sum of chemical misfit of RE and chemical misfit of X was negative with a bigger numerical value. The present results were helpful for further investigation on strengthening-toughening of magnesium alloys for LPSO was found to increase the strength and toughness of magnesium alloys effectively. [ABSTRACT FROM AUTHOR]

Although the effect of experimental warming on soil microorganisms has been well documented at surface horizons, less is known about its influence in subsurface horizons. An experiment was therefore carried out in an alpine meadow on the Qinghai- Tibet Plateau to examine the responses of microbial communities to experimental warming at five soil depths (0-10, 10-20, 20-30, 30-40 and 40-50 cm). Plots were passively warmed for 3 years in open-top chambers and compared with adjacent control plots at ambient temperature. Soil microbial communities were assessed by using phospholipid fatty acid ( PLFA) analysis. Our results showed clearly that 3 years of experimental warming increased microbial biomass consistently and significantly throughout the upper 50-cm soil profiles, as indicated by the changes in both microbial biomass carbon ( C) and total PLFA contents. The composition of microbial communities was also affected significantly by warming, but its effect depended on soil depth. While warming induced a community shift towards bacteria at the 0-10-cm depth, it tended to shift microbial communities towards fungi at the other, deeper, layers. These results indicate that warming had strong effects on soil microbial communities, including even those residing in subsurface horizons, which may help us to understand the microbial mediation of the feedback between terrestrial C cycling and climate warming. [ABSTRACT FROM AUTHOR]

Canine distemper virus (CDV) is the cause of canine distemper (CD) which is a severe and highly contagious disease in dogs. In the present study, a duplex reverse transcription polymerase chain reaction (RT-PCR) method was developed for the detection and differentiation of wild-type and vaccine strains of CDV. Four primers were designed to detect and discriminate the two viruses by generating 638- and 781-bp cDNA products, respectively. Furthermore, the duplex RT-PCR method was used to detect 67 field samples suspected of CD from Guangdong province in China. Results showed that, 33 samples were to be wild-type-like. The duplex RT-PCR method exhibited high specificity and sensitivity which could be used to effectively detect and differentiate wild-type and vaccine CDV, indicating its use for clinical detection and epidemiological surveillance. [ABSTRACT FROM AUTHOR]

Rapid degradation of cell performance still remains a significant challenge for proton exchange membrane fuel cell (PEMFC). In this work, we develop novel CeO2 nanocubes-graphene oxide nanocomposites as durable and highly active catalyst support for proton exchange membrane fuel cell. We show that the use of CeO2 as the radical scavenger in the catalysts remarkably improves the durability of the catalyst. The catalytic activity retention of Pt-graphene oxide-8 wt.% CeO2 nanocomposites reaches as high as 69% after 5000 CV-cycles at a high voltage range of 0.8-1.23 V, in contrast to 19% for that of the Pt-graphene oxide composites. The excellent durability of the Pt-CeO2 nanocubes-graphene oxide catalyst is attributed to the free radical scavenging activity of CeO2, which significantly slows down the chemical degradation of Nafion binder in catalytic layers, and then alleviates the decay of Pt catalysts, resulting in the excellent cycle life of Pt-CeO2-graphene oxide nanocomposite catalysts. Additionally, the performance of single cell assembled with Nafion 211 membrane and Pt-CeO2-graphene oxide catalysts with different CeO2 contents in the cathode as well as the Pt-C catalysts in the anode are also recorded and discussed in this study. [ABSTRACT FROM AUTHOR]

Al doped ZnO (AZO) thin films were synthesised on quartz glass substrates by pulsed laser deposition (PLD) method at different oxygen flowrates. The structure, composition, optical and electrical properties in the films were investigated. The result of surface profiler shows that with the increase in oxygen flowrate from 10 to 70 sccm, the films' thickness increases from 526 to 706 nm. X-ray diffraction results show that the crystalline quality of the films is improved with the increase in oxygen flowrate; energy dispersive spectroscopy results exhibit that the Al content in the films increases from 4·32 to 6·45% with the increase in oxygen flowrate. The former leads to the weakening of grain boundary scattering; consequently, Hall mobility will increase, and the latter results in the increase in carrier concentration. As a result, the electrical resistivity in AZO films decreases from 10·92×10−3 to 2·34×10−3 Ω cm with increasing the oxygen flowrate. Moreover, the increase in carrier concentration induces the slight widening of optical band gap due to the Burstein-Moss effect with the increase in oxygen flowrate. For AZO thin films grown by the PLD method, the control of oxygen flowrate is a simple method to obtain adjustable electrical resistivity, optical band gap and ultraviolet emission. [ABSTRACT FROM AUTHOR]

Al doped ZnO (AZO) thin films were synthesised on single crystal silicon and quartz glass substrates by pulsed laser deposition method at different O2 partial pressure. The structure, composition, optical and electrical properties in AZO thin films were investigated. With the increase in O2 partial pressure, the crystalline quality of AZO thin films becomes poor, and the Al content in the films decreases from 6·3 to 4·3%. The former leads to the enhancement of grain boundary scattering, consequently Hall mobility will decrease. While the latter results in the decrease of carrier concentration. As a result, the electrical resistivity in AZO thin films increases from 2·18×10−4 to 13·40×10−4 Ω cm with increasing the O2 partial pressure. The increase of carrier concentration induces the widening of optical band gap due to the Burstein-Moss effect with the increase of O2 partial pressure. For AZO thin films grown by PLD method, the control of O2 partial pressure is a simple method to adjust the electrical resistivity, optical band gap and UV emission in the films. [ABSTRACT FROM AUTHOR]

Three CuO/CeO2 catalyst with different morphologies of ceria, namely nanospheres, nanorods and nanocubes, were synthesized and used to catalyze the water-gas shift (WGS) reaction. The reactivity tests showed that the Cu supported on the ceria nanospheres exhibited both the highest activity and superior stability when compared with the nanocube and nanorod ceria catalysts. Operando X-ray diffraction (XRD), X-ray absorption fine structure (XAFS) and diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) methods were used to characterize these catalysts in their working state. High resolution electron microscopy (HRTEM, STEM) was used to look at the local atomic structure and nano-scale morphology. Our results show that the morphology of the ceria support, which can involve different crystal faces and concentrations of defects and imperfections, has a critical impact on the catalytic properties and influences: (1) the dispersion of CuO in the as-synthesized catalyst; (2) the particle size of metallic Cu upon reduction during the WGS reaction, (3) the stability of the metallic Cu upon variations of temperature, and (4) the dissociation of water on the ceria support. The nanosphere ceria catalyst showed an excellent water dissociation capability, the best dispersion of Cu and a strong Cu–Ce interaction, therefore delivering the best performance among the three WGS catalysts. The metallic Cu, which is the active species during the WGS reaction, was more stabilized on the nanospheres than on the nanorods and nanocubes and thus led to a better stability of the nanosphere catalyst than the other two architectures. Each catalyst exhibited a distinctive line-shape in the 800–1600 cm−1 region of the DRIFTS spectra, pointing to the existence of different types of carbonate or carboxylate species as surface intermediates for the WGS. [ABSTRACT FROM AUTHOR]

Let G be a finite group and T(G) the prime graph of G. Recently people have been using prime graphs to study simple groups. Naturally we pose a question: can we use prime graphs to study almost simple groups or non-simple groups? In this paper some results in this respect are obtained and as follows: G ≌ Sp if and only if ￨G￨ = ￨Sp￨ and T(G) = T(Sp), where p is a prime. [ABSTRACT FROM AUTHOR]

Al doped ZnO (AZO) thin films are of significant interest for flat panel displays, solar cells, etc. In this regard, AZO films were prepared in Ar atmosphere by radio frequency magnetron sputtering with an AZO (2 wt-%Al2O3) ceramic target at room temperature. To investigate the influence of hydrogen related defects on the structure and optoelectronic properties in AZO films, the prepared films were annealed in Ar+H2 ambient at different temperatures (100-500°C). The results show that the films' crystallinity becomes better and the resistivity decreases with the increase in annealing temperature. The lowest resistivity of 2·79×10−3 Ω cm is obtained after 500°C hydrogen annealing, which decreases by about four orders of magnitude compared to the resistivity of as deposited film. The improvement of electrical properties is attributed to the formation of H related defects and desorption of weakly bonded oxygen species near grain boundaries in AZO films after H2 annealing treatment, and the corresponding physical mechanism was discussed. It is proved that hydrogen annealing is an effective method for the improvement of electrical properties in AZO thin films. The optical bandgap energy of the films obviously increases with the increase in annealing temperature due to Burstein-Moss effect. [ABSTRACT FROM AUTHOR]

A type of all-optical switches using solitons within nonlinear fibers is studied in this paper. Analytic two-soliton solutions for the coupled nonlinear Schrödinger equations are derived with symbolic computation and Hirota method. Inelastic interactions between solitons are displayed, and the all-optical switching dynamics is analyzed. The high-intensity light is controlled with the low-intense light in the anomalous dispersion regime of fibers. Besides, the bright solitons for the all-optical switches are obtained in the normal dispersion regime of fibers. Influences of the fiber nonlinearity, group-velocity dispersion, and reciprocal of the group velocity are discussed. Nonlinear effects in the normal dispersion regime of fibers has less impact than them in the anomalous dispersion regime, and the switching threshold power is adapted through changing the group velocity. All-optical switches can be achieved with a short fiber length through increasing the group-velocity dispersion, and the size of optical circuits can be reduced without the dispersion limit. Results of this paper may drive potential applications of all-optical switches for computing, information processing, and networking. [ABSTRACT FROM PUBLISHER]

In order to effectively increase coal rate, replacement ratio of coal, and reduce the cost in a blast furnace, the injecting properties of a certain rank of coals, such as anthracite, meager-lean coal, bituminous coal, and their blends, have been evaluated one by one in this article. The results show that anthracite, meager-lean coal, and bituminous coal have different characteristics. The injecting properties, such as igniting point, explosivity, grindability, combustion characteristic, reactivity, etc., can be optimized to some extent with the different mixing proportion of the studied coals. Among them, combustion characteristic and reactivity are of vital importance because they are closely related to burning ratio. According to proper matching and integrated evaluation, the reasonable ratio of anthracite, meager-lean coal, and bituminous coal is chosen for improving coal rate in a blast furnace. [ABSTRACT FROM AUTHOR]

K(D0.12H0.88)2PO4 crystals were chosen to be used for quadratic nonlinear medium of wideband frequency doubling at 1 μm. A key limitation on this application is that little information can be found in the previous reports. In this work, growth as well as structural and optical properties of this crystal were investigated in detail. Experimental results in comparison with KDP indicate that lattice parameter along a-axis changes much more than lattice parameter c and infra-red absorption edge shift by 0.08 μm accompanied with increasing of transmittance in the whole region. With the introduction of deuterium atom, peak of ν1(PO4) shifts to lower wave number and transverse stimulated Raman scattering was effectively suppressed. Extra-ordinary and ordinary indices were also measured as function of wavelength. Good crystalline perfection and great performance of damage threshold also indicate that 12%-DKDP is an appropriate choice in the application of wideband frequency doubling at 1 μm. [ABSTRACT FROM AUTHOR]

An analytic study on soliton amplification in inhomogeneous optical fibers is presented in this paper. By use of the Hirota method, the bilinear forms for the nonlinear Schrödinger equation, which describes the soliton propagation in inhomogeneous optical fibers, are obtained. The analytic soliton solutions are derived with symbolic computation. According to the solution obtained, the solitons are amplified without the pedestals, and the technique permit high-quality amplification of solitons, which to our knowledge has not been reported before. The physical effects affecting soliton amplification are discussed. The gain of the amplifier, the soliton velocity and phase can be adjusted with two arbitrary parameters. The influences of group-velocity dispersion and Kerr nonlinearity on soliton amplification are studied. With the different values of group-velocity dispersion and Kerr nonlinearity, amplification of solitons in inhomogeneous optical fibers can be controlled. The results of this paper provide a simple and efficient approach to amplify solitons in the communication systems. [ABSTRACT FROM AUTHOR]

Fang Y, Wang L-P, Du F-L, Liu W-J, Ren G-L. Effects of insulin-like growth factor I on alveolar bone remodeling in diabetic rats. J Periodont Res 2013; 48: 144-150. © 2012 John Wiley & Sons A/S Background and Objective: Diabetes is a chronic hyperglycemic disorder and results in a tendency to develop osteoporosis. Furthermore, the delayed healing of tooth-extraction wounds, the activation of alveolar resorption and the suppressed formation of bone around implants are difficult for dentists to resolve. In diabetes, insulin-like growth factor I (IGF-I) appears to enhance the differentiation of osteoblasts and to activate the mineralization of bone. Hence, the aim of this study was to investigate the effects of insulin-like growth factor I on the remodeling of alveolar bone in diabetic rats. Material and Methods: Diabetes was induced in 40 male Sprague-Dawley rats by intravenous administration of alloxan. The teeth of the rats were extracted to investigate remodeling of alveolar bone. Insulin-like growth factor I was administered, via intraperitoneal injection, to diabetic rats following tooth extraction. The remodeling of alveolar bone was determined using radiographic data, histological analyses and tetracycline fluorescence labeling. Results: Compared with the control group, diabetes decreased alveolar bone formation. The height of alveolar bone and the bone-formation rate was significantly lower in the untreated diabetic group than in the control group or in the treated rats. Treatment with insulin-like growth factor I not only regulated abnormal blood glucose levels but also increased the height of the alveolar bone and increased the bone-formation rate relative to the results in diabetic animals. Furthermore, the expression of glucose transporter-1, the main transporter of glucose, was changed by hyperglycemia. Conclusion: The results suggest that insulin-like growth factor I treatment increases the volume of newly formed bone following tooth extraction and normalizes the expression of glucose transporter-1 in diabetic rats, which may play an important role in bone formation and mineralization. [ABSTRACT FROM AUTHOR]

In this paper, we study the effect of highly doped n^+/p^+ Si as the bottom electrode on unipolar RRAM with Ni-electrode/\HfOx structure. With heavily doped p^+-Si as the bottom electrode, RRAM devices illustrate the coexistence of the bipolar and the unipolar resistive switching. Meanwhile, by substituting heavily doped n^+-Si, the switching behavior changes to that of the self-rectifying unipolar device. The asymmetry and rectifying reproducible behavior in a n^+-\Si/HfOx/\Ni device resulted from the Schottky barrier of defect states in the \SiOx/\HfOx junction and n^+ Si substrate, but this behavior is not seen for the p^+-Si bottom electrode case. With rectifying characteristics and high forward current density observed in the \Ni/HfOx/\n^{+}\Si device, the sneak current path in the conventional crossbar architecture was significantly suppressed. We believe that the proposed structure is a promising candidate for future crossbar-type RRAM applications. [ABSTRACT FROM AUTHOR]

We prospectively evaluated the CEL-100 videolaryngoscopeTM for insertion of double-lumen tracheal tubes in 48 consecutive patients who had been found to have an unanticipated Cormack and Lehane grade 3 (n = 43) and grade 4 (n = 5) laryngeal view and in whom two attempts at tracheal intubation using the Macintosh laryngoscope had failed. When the CEL-100 was subsequently employed, the glottic view improved in 45 (94%) patients. The view improved by one grade in 15 (31%) patients and by two grades in 30 (63%) patients, compared with the Macintosh blade (p < 0.001). Double-lumen tracheal tube insertion was successful when using the CEL-100 in 43 out of 48 patients (90%; 95% CI 81-98%). This occurred on the first attempt in 27 (56%) patients, 14 (29%) on the second and two (4%) on the third. We conclude that the CEL-100 videolaryngoscope is an effective device in this context, and we therefore propose that this device can be used in circumstances when double-lumen tube insertion proves difficult. [ABSTRACT FROM AUTHOR]

Objective: In addition to tight glucose control, early intensive therapy has been reported to be more important for the prevention of diabetic micro- and macro-vascular complications. What is not known exactly is the quantitative difference according to timing delay in glucose control and whether early period control is really better than late control in terms of diabetic peripheral neuropathy. In this study, we investigated the effect of timing differences in glucose control on the peripheral nerves in an experimental diabetic model. Methods: 5 groups (6-8 rats in each group) were comprised of normal glucose rats (designated control), rats with hyperglycemia (designated DM), rats with glucose control for the entire 28-week study period (designated DM + INS [W0-28]), rats with glucose control for the early 14-week period followed by hyperglycemia for the late 14-week period (designated DM + INS [W0-14]), and rats with hyperglycemia for the early 14-week period followed by glucose control in the late 14-week period (designated DM + INS [W15-28]). Results: We found that the current perception threshold (CPT) was lower in the DM + INS (W0- 28) and DM + INS (W15-28) groups than in the DM + INS (W0-14) or DM groups ( P < 0.05). The mean myelinated fiber area of the sciatic nerve was significantly greater in the DM + INS (W0- 28) and DM + INS (W15-28) groups (63.5 ± 2.32 and 60.1 ± 2.14 um, respectively) than in the DM + INS (W0-14) or DM groups (55.5 ± 2.81 or 51.5 ± 2.64 um, respectively) ( P < 0.05), and the intraepidermal nerve fiber (IENF) density was significantly higher in the DM + INS (W0-28) and DM + INS (W15-28) groups (6.9 ± 0.46 and 6.8 ± 0.11, respectively) than in the DM + INS (W0-14) or DM groups (59.5 ± 0.32 and 5.3 ± 0.39/mm, respectively) ( P < 0.05). Conclusion: Our results indicate that continuous glucose control is necessary to alleviate peripheral nerve damage and that glycemic control during the later period may be more important than early period management. The importance of continuous glucose control, including the later period of diabetes, should therefore be emphasized in diabetic peripheral neuropathy. [ABSTRACT FROM AUTHOR]

Raman measurement is carried out to understand Vth shift in single-layer graphene field-effect transistors (GFETs). The G (2D) peak shift in Raman spectra is correlated to the corresponding \Delta Vth during stress and recovery phases. A blue (red) shift of G and 2D peaks is seen during stress (recovery) phase, indicating the corresponding trapping (detrapping) effects in the graphene device. It is interesting to note that, after forming gas annealing (\H2/\Ar), the defects can be generated in graphene (evidenced by D peak of Raman spectra), leading to the increased \Delta Vth for both negative bias temperature instability and positive bias temperature instability in single-layer GFETs. [ABSTRACT FROM PUBLISHER]