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The first Lower Hybrid (LH) experiments were carried out with a Passive-Active Multijunction (PAM) launcher in H-mode plasmas. The experiments were performed on the HL-2A tokamak with the new 3.7 GHz LHCD system, installed and tested by SWIP in collaboration with CEA/RFM. The ELMs and local gas impact on LH power coupling was studied in the experiments. The coupled LH power in HL-2A was 200-500kW at large gap at the first experiments and reaches 900 kW now in H-mode, while it reaches 1MW in L-mode. The LH experiments on HL-2A show that the PAM launcher is a viable concept for high performance scenarios. The LH power can be coupled at large plasma-launcher gap, and assist in triggering and sustaining H-modes. Finally, an overview of the RF heating systems for the tokamak HL-2M is given. HL-2M will dispose of a 4 MW LH system and a 8 MW ECRH system, both of which are currently under installation at SWIP.

In this article, we demonstrate the inference of two-dimensional tungsten concentration profiles in tokamak plasmas, using Gaussian process tomography applied to bolometry and assuming a specific model for the tungsten cooling factor. In ITER, tungsten has been selected for divertor material due to its low tritium retention and ability to handle large heat and particle flux loads. On the other hand, this will cause tungsten impurities to enter the bulk plasma through various plasma-wall interaction processes. Therefore, a detailed understanding of tungsten impurity transport and active control of the impurity transport in tokamaks is crucial. The computational complexity of the method described in their article O n 2 m compares favorably to a simple least-squares approach O n 3 , n represents the number of pixels and m the number of measurement channels, hence bringing real-time tungsten profile monitoring within reach (<10 ms repetition time). The feasibility study of this method has been demonstrated here to a discharge in HL-2A for observing the entire process of tungsten impurities entering the bulk plasma from the scrape-off layer area, tungsten pump-out by edge-localized modes, as well as the formation of a poloidally asymmetric tungsten distribution. [ABSTRACT FROM AUTHOR]

The supersonic molecular beam injection (SMBI) technique is widely used in magnetic fusion devices for plasma fueling and active control of particles. The beam flow formed by the SMBI system is directly visualized by a newly established schlieren diagnostic system on the SMBI testing platform. This schlieren system could provide a 2D density distribution of the beam with the sub-mm spatial resolution by detecting the change in the refractive index of the medium caused by the SMBI in the low-pressure vacuum chamber. The structure and the divergence angle of the supersonic molecular beam for fusion plasma fueling are first measured. Additionally, the density profile of the supersonic molecular beam is reconstructed from the measured light intensity by the schlieren system. The experimental comparison between the standard nozzle and the optimized nozzle of the SMBI system shows the great potential of the diagnostic system in optimizing the beam characteristics. [ABSTRACT FROM AUTHOR]

In this paper, a novel approach is proposed to calibrate an underwater fisheye camera with the multi-frequency heterodyne technique based on the light field. First, an underwater fisheye camera imaging model based on the light field is established to demonstrate the multiple refractions of light in underwater propagation and the extraordinary imaging characteristics of the fisheye lens, which shows better conciseness and organization. Then, the calibration method applied in the underwater fisheye camera imaging system is proposed to determine the mapping of the light field and the pose of the underwater fisheye camera. The light field mapping of the fisheye lens is obtained with the assistance of the multi-frequency heterodyne technique. Finally, an underwater fisheye camera is developed and the experimental results are obtained to validate the correctness and feasibility of the proposed method. Our underwater imaging system proves capable of achieving higher accuracy in the context of underwater 3D measurement. [ABSTRACT FROM AUTHOR]

Background: Numerous studies have reported that systemic immune-inflammation index (SII) and C-reactive protein-to-albumin ratio (CAR) correlate with tumor progression and prognosis in various types of human cancer. The aim of this study is to systematically investigate the clinical significance of SII and CAR in esophageal cancer (EC). Methods: We searched a number of databases for articles reporting the effect of pretreatment SII and CAR on the survival of EC patients. Review Manager 5.3 and STATA/SE 14.1 were applied in this meta-analysis. The multivariable-adjusted hazard ratio (HR) was used for calculating the relationship between SII and CAR and overall survival (OS), and the odds ratio (OR) was applied for the clinical pathology. Results: Five original studies for SII and seven original datasets for CAR were included for analysis. Increased SII showed a significant association with shorter OS in EC patients after surgery (HR: 1.34, 95% CI: 1.15–1.53, P<0.001) and high CAR indicated worse long-term OS in EC (HR: 1.60, 95% CI: 1.29–1.90, P<0.001). Different subgroup analyses were also confirmed the prognostic roles in EC patients. Furthermore, the adverse impacts of elevated SII and CAR on tumor progression were revealed in the infiltration depth, lymph node metastasis, and clinical stage. Conclusions: Both pretreatment SII and CAR might be promising predictors of cancer survival and tumor progression in EC. Further studies are warranted to verify the clinical usefulness in patients with EC. [ABSTRACT FROM AUTHOR]

Soil nitrogen (N) loss has been predicted to intensify with increased global precipitation changes. However, the relative contributions of leaching and gaseous N emissions to intensified N losses are largely unknown. Thus, we simulated intensified precipitation seasonality in a subtropical forest by extending the dry season via rainfall exclusion and increasing the wet‐season storms via irrigation without changing the total annual precipitation. Extending the dry season length increased the monthly mean soil NO3− content by 25%–64%, net N mineralization rate by 32%–40%, and net nitrification rate by 25%–28%. After adding water in the wet season, the monthly NO3− leaching was enhanced by 43% in the relatively dry year (2013, 2,094‐mm annual rainfall), but reduced by 51% in the relatively wet year (2014, 1,551 mm). In contrast, the monthly mean N2O emissions were reduced by 24% in 2013 but increased by 78% in 2014. Overall, the annual inorganic N content was decreased significantly by the precipitation changes. Decrease of soil inorganic N might be linked to the enhanced NO3− leaching in 2013, and be linked to the increased N2O emissions in 2014. However, in both years the annual total amount of N lost through leaching was significantly greater than that through N2O emissions. The enhanced N2O emissions driven by wet‐season storms were correlated with an increase in nirS abundance. Our results suggest that increased frequency of droughts and storms will decrease soil inorganic N content in warm and humid subtropical forests mainly through enhanced leaching losses. Key Points: Soil NO3− content was increased by dry season extension and decreased by more abundant wet‐season storms in a subtropical forestThe N loss caused by leaching was much greater than that through N2O emissionsPrecipitation‐induced increases in net nitrification and N2O emissions were related to increases in archaea amoA and nirS gene abundances [ABSTRACT FROM AUTHOR]

The study reported in this Research Communication was carried out to examine how parity and milking time affected donkey milk yield under a typical Chinese production system. Eighteen Jiangyue breed donkeys with good health condition, aged between 6 and 9 years, and with parities 3 and 4, were selected. Milk production was measured commencing from the fourth week post-foaling, with a total data collection of 170 d in milk (lactation length). Mean milk yield of the donkeys used in this study was 3·0 kg/donkey/d. Results showed milk yield decreased with days in milk from 3·3 kg/donkey/d at the start of the study, to 2·2 kg/donkey/d by the end of the 170 d. Parity 3 donkeys produced 22% more milk than parity 4 donkeys (3·3 kg/donkey/d vs 2·7 kg/donkey/d). The information provided by this study should aid producers in estimating the expected milk yields from individual donkey, and better predict milk yield over the course of a production cycle. [ABSTRACT FROM PUBLISHER]

A hierarchically porous Sr2Fe1.5Mo0.5O6− δ-Gd0.1Ce0.9O1.95 (SFM-GDC) ceramic anode-supported solid-oxide fuel cell with a GDC electrolyte film was fabricated by freeze-drying tape-casting and drop coating. 3D X-ray computed tomography analysis indicated that the SFM-GDC anode has a high porosity and low tortuosity factor, facilitating gas diffusion in the anode during fuel cell operation. Peak power density of cells with a La0.6Sr0.4Co0.2Fe0.8O3-GDC (LSCF-GDC) cathode can reach 0.22 W cm−2 at 700 °C when using H2 as the fuel and ambient air as the oxidant. The SFM-GDC anode shows excellent sulfur tolerance when using H2 with 50 ppm H2S. SEM analysis demonstrates that the nanocatalyst (iron) can precipitate from the parent SFM phase upon reduction and iron nanoparticles can react with sulfur species to form needle-like nanosulfide. Both the nanocatalyst and sulfide show a graded distribution along the thickness direction, owing to a graded local oxygen chemical potential within the anode. [ABSTRACT FROM AUTHOR]

Abstract: The effect of p- and n-type dopants on ionic and electronic conductivity of SrTiO3 based perovskites were investigated both computationally and experimentally. Specifically, we performed density functional theory (DFT) calculations of Na- and La-doped SrTiO3 and Na- and Nb-doped SrTiO3 systems. Constrained ab initio thermodynamic calculations were used to evaluate the phase stability and reducibility of doped SrTiO3 under both oxidizing and reducing synthesis conditions, as well as under anodic solid oxide fuel cell (SOFC) conditions. The density of states (DOS) of these materials was analyzed to study the effects of p- and n-doping on the electronic conductivity. Furthermore, Na- and La-doped SrTiO3 and Na- and Nb-doped SrTiO3 samples were experimentally prepared and the conductivity was measured to confirm our computational predictions. The experimental observations are in very good agreement with the theoretical predictions that doping n-doped SrTiO3 with small amounts of p-type dopants promotes both the ionic and electronic conductivity of the material. This doping strategy is valid independent of p- and n-doping site and permits the synthesis of perovskite based mixed ionic/electronic conductors. [Copyright &y& Elsevier]

Donor and acceptor co-doped SrTiO3 materials have shown interesting features in their conductivity and reducibility. In this work, 10 mol% Na+ or K+ as acceptor dopants have been introduced into the A-site of donor-doped strontium titanate, SrTi0.8Nb0.2O3, and the doping impact on their properties has been studied. By doping with Na or K, the sinterability of SrTi0.8Nb0.2O3 in reducing atmospheres has been improved. Na0.1Sr0.9Ti0.8Nb0.2O3 and K0.1Sr0.9Ti0.8Nb0.2O3 show metallic conduction behavior after being sintered at 1400 °C in 5% H2/N2. Electrical conductivity reaches 1180 S cm−1 at 400 °C and 272 S cm−1 at 800 °C for K0.1Sr0.9Ti0.8Nb0.2O3, which is higher than that of Sr0.99Ti0.8Nb0.2O3 prepared under similar conditions, indicating the improved reducibility of acceptor doped SrTi0.8Nb0.2O3. Such improvement may be attributed to the improved oxide ionic conductivity and cation mobility at high temperatures. Reduced polarization resistance is also observed using Na0.1Sr0.9Ti0.8Nb0.2O3 and K0.1Sr0.9Ti0.8Nb0.2O3 as anodes on YSZ electrolytes, suggesting improved catalytic activity by Na/K-doping. [ABSTRACT FROM AUTHOR]

Abstract: This paper demonstrates the potential application of Mo-doped SrFeO3−δ perovskites as new cathode materials for solid oxide fuel cells (SOFCs). SrFe1−x Mo x O3−δ (x =0, 0.05, 0.1, 0.2 and 0.25) perovskite materials have been synthesized by a microwave-assisted combustion method. By doping with Mo, the electrical conductivity of the doped SrFeO3−δ in air is reduced with increasing amounts of Mo. At 800°C, the conductivity drops from about 62 to 22Scm−1 when the doping level is increased to 25%. According to X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and temperature programmed reduction (TPR) results, a decrease in the concentration of charge carrier Fe4+ ions may account for the decrease in electrical conductivity. In contrast, the resistance to sintering and tolerance to reduction of SrFeO3−δ are improved by Mo-doping. Additionally, the thermal expansion coefficient at 800°C drops from 40.8×10−6 K−1 for SrFeO3−δ to 25.7×10−6 K−1 for SrFe0.8Mo0.2O3−δ and 20.9×10−6 K−1 for SrFe0.75Mo0.25O3−δ . This significant decrease in the thermal expansion coefficient makes Mo-doped SrFeO3−δ materials attractive as cathode candidates for SOFCs. Finally, a relatively low polarization resistance of 0.074Ωcm2 is obtained for SrFe0.8Mo0.2O3−δ at 800°C in air. [Copyright &y& Elsevier]

Abstract: The effects of reduction and Ga-doping on the physicochemical properties of A-site deficient perovskites Sr0.9Ti0.8−x Ga x Nb0.2O3 (x =0, 0.05, 0.1, 0.15 and 0.2) are reported. With 10% Ga doping, the sample sintered in air and treated at 1400°C in H2 atmosphere exhibits the highest electrical conductivity. It is found that the Ga-doping lowers the sinterability but promotes the reduction of Sr0.9Ti0.8−x Ga x Nb0.2O3. The XRD analysis on the reduced samples suggests that some cations are reduced during the treatment. However, without high temperature pre-reduction, the improvement of Ga-doping is limited and the overall cell performance using Sr0.9Ti0.8−x Ga x Nb0.2O3 as an anode without catalysts is still relatively low. [ABSTRACT FROM AUTHOR]

Abstract: Sr2Fe4/3Mo2/3O6 has been synthesized by a combustion method in air. It shows a single cubic perovskite structure after being reduced in wet H2 at 800°C and demonstrates a metallic conducting behavior in reducing atmospheres at mediate temperatures. Its conductivity value at 800°C in wet H2 (3% H2O) is about 16Scm−1. This material exhibits remarkable electrochemical activity and stability in H2. Without a ceria interlayer, maximum power density (P max) of 547mWcm−2 is achieved at 800°C with wet H2 (3% H2O) as fuel and ambient air as oxidant in the single cell with the configuration of Sr2Fe4/3Mo2/3O6|La0.8Sr0.2Ga0.83Mg0.17O3 (LSGM)| La0.6Sr0.4Co0.2Fe0.8O3 (LSCF). The P max even increases to 595mWcm−2 when the cell is operated at a constant current load at 800°C for additional 15h. This anode material also shows carbon resistance and sulfur tolerance. The P max is about 130mWcm−2 in wet CH4 (3% H2O) and 472mWcm−2 in H2 with 100ppm H2S. The cell performance can be effectively recovered after changing the fuel gas back to H2. [ABSTRACT FROM AUTHOR]

Abstract: Sr2Fe1.5Mo0.5O6 (SFMO) shows good chemical compatibility with NiO under 1000°C. By dispersing a small amount of Ni (~2wt%) into the SFMO anode, the performance of the fuel cells with La0.8Sr0.2Ga0.83Mg0.17O3 (LSGM) electrolyte and La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) cathode is dramatically improved. With ambient air as the oxidant, the cell peak power density reaches 1.134Wcm−2 in wet H2 (3vol% H2O) and 0.663Wcm−2 in wet CH4 (3vol% H2O) at 800°C. Stable cell performance is achieved when operating the cell with CH4 as fuel at 0.7V, indicating no significant carbon formation on the Ni-modified SFMO anode. Considering the simple anode fabrication procedure and the relatively low cost of the anode materials, Ni modified SFMO ceramic anode shows great promise for direct-methane solid oxide fuel cells. [Copyright &y& Elsevier]

This image represENts a hierarchically porous Sr2Fe1.5Mo0.5O6−δ–Gd0.1Ce0.9O1.95 (SFM ‐ GDC) ceramic anode ‐ supported solid ‐ oxide fuel cell with a GDC electrolyte film. The nanocatalyst can precipitate from the parENt SFM phase upon reduction and can react with sulfur species in the fuel to form needle ‐ like nanosulfides with a gradiENt distribution (i.e. less the nanosulfide closer to the electrolyte), demonstrating excellENt sulfur tolerance of the SFM ‐ GDC ceramic anode, as shown by M. Han, F. ChEN et   al. on p.   672. [ABSTRACT FROM AUTHOR]

To explore the importance of soil microbial community composition on explaining the difference in heterotrophic soil respiration (Rh) across forests, a field investigation was conducted on Rh and soil physiochemical and microbial properties in four subtropical forests in southern China. We observed that Rh differed significantly among forests, being 2.48 ± 0.23, 2.31 ± 0.21, 1.83 ± 0.08 and 1.56 ± 0.15 μmol m−2 s−1 in the climax evergreen broadleaf forest (BF), the mixed conifer and broadleaf forest (CF), the conifer plantation (CP), and the native broadleaved species plantation (BP), respectively. Both linear mixed effect model and variance decomposition analysis indicated that soil microbial community composition derived from phospholipid fatty acids (PLFAs) was not the first-order explanatory variable for the Rh variance across the forests, with the explanatory power being 15.7%. Contrastingly, vegetational attributes such as root biomass (22.6%) and soil substrate availability (18.6%) were more important for explaining the observed Rh variance. Our results therefore suggest that vegetation attributes and soil carbon pool size, rather than soil microbial community composition, should be preferentially considered to understand the spatial Rh variance across the subtropical forests in southern China. [ABSTRACT FROM AUTHOR]

Abstract: Sr2Fe1.5Mo0.5O6−δ (SFM) was prepared using a microwave-assisted combustion synthesis method. Rietveld refinement of powder X-ray diffraction data reveals that SFM crystallizes in the simple cubic perovskite structure with iron and molybdenum disordered on the B-site. No structure transition was observed by variable temperature powder X-ray diffraction measurements in the temperature range of 25–800°C. XPS results show that the iron and molybdenum valences change with an increase in temperature, where the mixed oxidation states of both iron and molybdenum are believed to be responsible for the increase in the electrical conductivity with increasing temperature. SFM exhibits excellent redox stability and has been used as both anode and cathode for solid oxide fuel cells. Presence of sulfur species in the fuel or direct utilization of hydrocarbon fuel can result in loss of activity, however, as shown in this paper, the anode performance can be regenerated from sulfur poisoning or coking by treating the anode in an oxidizing atmosphere. Thus, SFM can be used as a regenerating anode for direct oxidation of sulfur-containing hydrocarbon fuels. [Copyright &y& Elsevier]

Highlights: [•] SFM incorporates several fission products into the crystalline simultaneously. [•] Helium irradiation created a reduced atmosphere on the surface of SFM sample. [•] Irradiated SFM decomposed into a Sr4FeMoO8−δ based phase and a Fe metallic phase. [•] Nano-crystalized grains with particle sizes of 7nm formed due to He irradiation. [•] Stability in reducing atmosphere may be considered for future crystalline FP host. [ABSTRACT FROM AUTHOR]

Abstract: Catalyst of nickle oxide based on flowerlike cerium microspheres with high dispersion was made to achieve simultaneous dehydrogenation of ethanol and water molecules on multi-active sites. XRD, 77KN2 adsorption and FESEM were applied to analyse and observe the catalyst''s structure, porosity and morphology. This special morphology catalyst represented novel stability more than 600h for hydrogen production at low temperature ethanol steam reforming. Ethanol-water mixtures could be converted into H2 with average selectivity value of 61.5mol.% and average ethanol conversion 95.0mol.% at 350°C, with GHSV∼1.0×105 h−1, low CO selectivity about average value of 2.1mol.%, during 550h reforming stability test. Catalytic parameters with respect to yield of H2, activity, selectivity towards hydrogen production and stability with time on stream were determined. [Copyright &y& Elsevier]

Abstract: Sr2Fe1.5Mo0.5O6 is a mixed ionic and electronic conductor which can be applied as both cathode and anode material in intermediate-temperature solid oxide fuel cells. To enhance its cathode performance, Ce0.8Sm0.2O1.9 nanoparticles are deposited using ion impregnation technique. Impedance spectroscopy shows that the nanoparticles are very effective in reducing the interfacial polarization resistance from 0.27Ωcm2 to 0.11Ωcm2 at 750°C. Electrical conductivity relaxation (ECR) measurement demonstrates that the surface exchange coefficient of Sr2Fe1.5Mo0.5O6 is significantly improved by the nanoparticles, from 10−5 to 10−3 cms−1 at 750°C. The results suggest that doped ceria nanoparticles are very promising in enhancing the surface exchange processes and consequently can greatly improve the electrode performance. [Copyright &y& Elsevier]