Showing papers by "Anhui Normal University published in 2016"
Paris Diderot University1, Nanjing University2, University of Helsinki3, Chinese Academy of Sciences4, Leiden University5, European Southern Observatory6, Ludwig Maximilian University of Munich7, Korea Institute for Advanced Study8, University of Sussex9, Anhui Normal University10, Yale University11, University of Hawaii12
TL;DR: In this paper, the authors reported the discovery of a remarkable concentration of massive galaxies with extended X-ray emission at z(spec) = 2.506, which contains 11 massive (M-* greater than or similar to 10(11) M-circle dot) galaxies in the central 80 kpc region (11.6 sigma overdensity).
Abstract: We report the discovery of a remarkable concentration of massive galaxies with extended X-ray emission at z(spec) = 2.506, which contains 11 massive (M-* greater than or similar to 10(11) M-circle dot) galaxies in the central 80 kpc region (11.6 sigma overdensity). We have spectroscopically confirmed 17 member galaxies with 11 from CO and the remaining ones from Ha. The X-ray luminosity, stellar mass content, and velocity dispersion all point to a collapsed, cluster-sized dark matter halo with mass M-200c = 10(13.9 +/- 0.2) M-circle dot, making it the most distant X-ray-detected cluster known to date. Unlike other clusters discovered so far, this structure is dominated by star-forming galaxies (SFGs) in the core with only 2 out of the 11 massive galaxies classified as quiescent. The star formation rate (SFR) in the 80 kpc core reaches similar to 3400 M-circle dot yr(-1) with a. gas depletion time of similar to 200 Myr, suggesting that we caught this cluster in rapid build-up of a dense core. The high SFR is driven by both a high abundance of SFGs and a higher starburst fraction (similar to 25%, compared to 3%-5% in the field). The presence of both a collapsed, cluster-sized halo and a predominant population of massive SFGs suggests that this structure could represent an important transition phase between protoclusters and mature clusters. It provides evidence that the main phase of massive galaxy passivization will take place after galaxies accrete onto the cluster, providing new insights into massive cluster formation at early epochs. The large integrated stellar mass at such high redshift challenges our understanding of massive cluster formation.
157 citations
TL;DR: In this paper, a 3D Co3O4@NiO hierarchical nanowire array supported on nickel foam is fabricated by a facile hydrothermal method, which exhibits an ultrahigh specific capacitance of 1236.67 fg−1 and excellent cycling stability (5000 cycles) at a current density of 1.
140 citations
INAF1, University of Edinburgh2, Paris Diderot University3, Institut d'Astrophysique de Paris4, Université Paris-Saclay5, Space Telescope Science Institute6, University of Lisbon7, California Institute of Technology8, University of Strasbourg9, University of California, Santa Cruz10, University of Copenhagen11, University of Ferrara12, Anhui Normal University13, Nanjing University14
TL;DR: In this paper, the first public release of photometric redshifts, galaxy rest frame properties and associated magnification values in the cluster and parallel pointings of the first two Frontier Fields, Abell-2744 and MACS-J0416, is presented.
Abstract: Aims. We present the first public release of photometric redshifts, galaxy rest frame properties and associated magnification values in the cluster and parallel pointings of the first two Frontier Fields, Abell-2744 and MACS-J0416. The released catalogues aim to provide a reference for future investigations of extragalactic populations in these legacy fields: from lensed high-redshift galaxies to cluster members themselves.
Methods. We exploit a multiwavelength catalogue, ranging from Hubble Space Telescope (HST) to ground-based K and Spitzer IRAC, which is specifically designed to enable detection and measurement of accurate fluxes in crowded cluster regions. The multiband information is used to derive photometric redshifts and physical properties of sources detected either in the H-band image alone, or from a stack of four WFC3 bands. To minimize systematics, median photometric redshifts are assembled from six different approaches to photo-z estimates. Their reliability is assessed through a comparison with available spectroscopic samples. State-of-the-art lensing models are used to derive magnification values on an object-by-object basis by taking into account sources positions and redshifts.
Results. We show that photometric redshifts reach a remarkable ~3–5% accuracy. After accounting for magnification, the H-band number counts are found to be in agreement at bright magnitudes with number counts from the CANDELS fields, while extending the presently available samples to galaxies that, intrinsically, are as faint as H ~ 32−33, thanks to strong gravitational lensing. The Frontier Fields allow the galaxy stellar mass distribution to be probed, depending on magnification, at 0.5–1.5 dex lower masses with respect to extragalactic wide fields, including sources at M_(star) ~ 10^7–10^8 M_⊙ at z > 5. Similarly, they allow the detection of objects with intrinsic star formation rates (SFRs) >1 dex lower than in the CANDELS fields reaching 0.1–1 M_⊙/yr at z ~ 6–10.
134 citations
INAF1, University of Edinburgh2, University of Lisbon3, Paris Diderot University4, University of Paris-Sud5, Institut d'Astrophysique de Paris6, Space Telescope Science Institute7, California Institute of Technology8, University of Strasbourg9, University of California, Santa Cruz10, Leiden University11, Anhui Normal University12, Nanjing University13
TL;DR: In this article, a robust and repeatable procedure that uses the public codes Galapagos and Galfit to model and remove most of the light contribution from both the brightest cluster members, and the intra-cluster light is presented.
Abstract: Context. The Frontier Fields survey is a pioneering observational program aimed at collecting photometric data, both from space (Hubble Space Telescope and Spitzer Space Telescope) and from ground-based facilities (VLT Hawk-I), for six deep fields pointing at clusters of galaxies and six nearby deep parallel fields, in a wide range of passbands. The analysis of these data is a natural outcome of the Astrodeep project, an EU collaboration aimed at developing methods and tools for extragalactic photometry and creating valuable public photometric catalogues.
Aims. We produce multiwavelength photometric catalogues (from B to 4.5 μm) for the first two of the Frontier Fields, Abell-2744 and MACS-J0416 (plus their parallel fields).
Methods. To detect faint sources even in the central regions of the clusters, we develop a robust and repeatable procedure that uses the public codes Galapagos and Galfit to model and remove most of the light contribution from both the brightest cluster members, and the intra-cluster light. We perform the detection on the processed HST H160 image to obtain a pure H-selected sample, which is the primary catalogue that we publish. We also add a sample of sources which are undetected in the H160 image but appear on a stacked infrared image. Photometry on the other HST bands is obtained using SExtractor, again on processed images after the procedure for foreground light removal. Photometry on the Hawk-I and IRAC bands is obtained using our PSF-matching deconfusion code t-phot. A similar procedure, but without the need for the foreground light removal, is adopted for the Parallel fields.
Results. The procedure of foreground light subtraction allows for the detection and the photometric measurements of ~2500 sources per field. We deliver and release complete photometric H-detected catalogues, with the addition of the complementary sample of infrared-detected sources. All objects have multiwavelength coverage including B to H HST bands, plus K-band from Hawk-I, and 3.6−4.5 μm from Spitzer. full and detailed treatment of photometric errors is included. We perform basic sanity checks on the reliability of our results.
Conclusions. The multiwavelength photometric catalogues are available publicly and are ready to be used for scientific purposes. Our procedures allows for the detection of outshone objects near the bright galaxies, which, coupled with the magnification effect of the clusters, can reveal extremely faint high redshift sources. Full analysis on photometric redshifts is presented in Paper II.
115 citations
Paris Diderot University1, Nanjing University2, University of Helsinki3, Chinese Academy of Sciences4, Leiden University5, European Southern Observatory6, Ludwig Maximilian University of Munich7, Korea Institute for Advanced Study8, University of Sussex9, Anhui Normal University10, Yale University11, University of Hawaii12
TL;DR: In this article, the authors reported the discovery of a massive galaxy with extended X-ray emission at 2.506, which contains 11 massive galaxies in the central 80kpc region (11.6$sigma$ overdensity).
Abstract: We report the discovery of a remarkable concentration of massive galaxies with extended X-ray emission at $z_{spec} = 2.506$, which contains 11 massive ($M_{*} \gtrsim 10^{11} M_{\odot}$) galaxies in the central 80kpc region (11.6$\sigma$ overdensity). We have spectroscopically confirmed 17 member galaxies with 11 from CO and the remaining ones from $H\alpha$. The X-ray luminosity, stellar mass content and velocity dispersion all point to a collapsed, cluster-sized dark matter halo with mass $M_{200c} = 10^{13.9\pm0.2} M_{\odot}$, making it the most distant X-ray-detected cluster known to date. Unlike other clusters discovered so far, this structure is dominated by star-forming galaxies (SFGs) in the core with only 2 out of the 11 massive galaxies classified as quiescent. The star formation rate (SFR) in the 80kpc core reaches $\sim$3400 $M_{\odot}$ yr$^{-1}$ with a gas depletion time of $\sim 200$ Myr, suggesting that we caught this cluster in rapid build-up of a dense core. The high SFR is driven by both a high abundance of SFGs and a higher starburst fraction ($\sim25\%$, compared to 3\%-5\% in the field). The presence of both a collapsed, cluster-sized halo and a predominant population of massive SFGs suggests that this structure could represent an important transition phase between protoclusters and mature clusters. It provides evidence that the main phase of massive galaxy passivization will take place after galaxies accrete onto the cluster, providing new insights into massive cluster formation at early epochs. The large integrated stellar mass at such high redshift challenges our understanding of massive cluster formation.
108 citations
TL;DR: A novel framework for estimating the hyper-connectivity network of brain functions and then using this hyper-network for brain disease diagnosis is proposed, which can not only improve the classification performance, but also help discover disease-related biomarkers important for disease diagnosis.
104 citations
TL;DR: It is demonstrated that cortical and specific subcortical areas play a pivotal role in the implementation of attentional functions and underlie their dynamic interactions.
100 citations
TL;DR: This short review focuses on some recent developments in the design, synthesis and structure of aluminum(iii) alkyl complexes supported by various ligands bearing nitrogen, oxygen, sulfur or phosphorus atoms, and their catalytic applications in the ring-opening polymerization (ROP) of cyclic esters.
Abstract: Aluminum alkyl complexes have very useful applications as catalysts or reagents in small molecule transformations and as cocatalysts in olefin polymerization. This short review focuses on some recent developments in the design, synthesis and structure of aluminum(iii) alkyl complexes supported by various ligands bearing nitrogen, oxygen, sulfur or phosphorus atoms, and their catalytic applications in the ring-opening polymerization (ROP) of cyclic esters. The coordination chemistry of the Al metal centre and the catalytic activity changes of the complexes caused by ligand modifications are also discussed.
96 citations
TL;DR: In this article, a hierarchical NiCo2O4@MnMoO4 core-shell nanomaterial on nickel foam was designed via a facile hydrothermal method.
Abstract: Hierarchical NiCo2O4@MnMoO4 core–shell nanomaterial on nickel foam was designed via a facile hydrothermal method. A possible growth mechanism of the MnMoO4 is in which the molybdenum acid radical captures part manganese ions of the MnMoO4 nanoflowers. When regarded as binder-free electrodes for supercapacitors (SCs), such special NiCo2O4@MnMoO4 core–shell hybrid electrodes exhibit ultra-high specific capacitances several times larger than a pristine NiCo2O4 electrode. The electrodes possess high specific capacitance of 1118 F g−1 at a current density of 1 A g−1 and excellent cycling stability (5000 cycles). This remarkable electrochemical performance is ascribed to the effective combination of two electroactive materials and the rational array configuration.
93 citations
TL;DR: Lutts et al. as discussed by the authors proposed a method to use Smart Molecular Memory (SMM) for smart molecular memory (SVM) at the Yonsei University in South Korea.
Abstract: Dr. K. Zhang, M. Ma, M. S. Jung, W. Kim, Prof. J. H. Park Department of Chemical and Biomolecular Engineering Yonsei University 50 Yonsei-ro , Seodaemun-gu , Seoul 120-749 Republic of Korea E-mail: lutts@yonsei.ac.kr Dr. L. Y. Wang, [+] Prof. H. Y. Lee National Creative Research Initiative Center for Smart Molecular Memory Department of Chemistry Energy Science and SAINT Sungkyunkwan University 2066 Seoburo, Jangan-Gu, Suwon , Gyeonggi-Do 440-746 Republic of Korea Prof. X. W. Sheng Department of Physics Anhui Normal University Anhui , Wuhu 241000 , P. R. China M. Ma SKKU Advanced Institute of Nanotechnology Sungkyunkwan University Suwon 440-746 , Republic of Korea W. Kim School of Chemical Engineering Sungkyunkwan University Suwon 440-746 , Republic of Korea
88 citations
TL;DR: The hierarchical core-shell MnCo2O4@MnO2 NWAs are very promising as next generation high-performance long-life cycling supercapacitors, via a facile, two-step hydrothermal approach without any adscititious surfactant and binder.
Abstract: In this paper, hierarchical MnCo2O4@MnO2 core–shell nanowire arrays (MnCo2O4@MnO2 NWAs) with mesoporous and large surface area are synthesized on 3D nickel foam via a facile, two-step hydrothermal approach without any adscititious surfactant and binder. The electrode architecture takes advantage of the synergistic effects contributed from both the porous MnCo2O4 nanowire core and the MnO2 shell layer. The fabricated MnCo2O4@MnO2 NWA electrode for supercapacitors in aqueous electrolyte exhibits a significantly enhanced specific capacitance (858 F g−1 at 1 A g−1), high energy density (36.0 Wh kg−1 at 252 W kg−1) and long-life cycling stability (retaining 88% of the initial capacitance after 5000 cycles). Then, a symmetrical supercapacitor is fabricated by assembling two MnCo2O4@MnO2 NWA-based electrodes, which shows a high specific capacitance of 678 F g−1 at 1 A g−1 and a high energy density of 135.6 Wh kg−1 at 513 W kg−1. Thereby, the hierarchical core–shell MnCo2O4@MnO2 NWAs are very promising as next generation high-performance long-life cycling supercapacitors.
TL;DR: In this paper, the authors investigated the approximate controllability of fractional stochastic differential inclusions with nonlocal conditions, and obtained a new set of sufficient conditions for the approximation of nonlinear FSD inclusions under the assumption that the corresponding linear system is approximately controllable.
Abstract: In this paper, we investigate the approximate controllability of fractional stochastic differential inclusions with nonlocal conditions. In particular, we obtain a new set of sufficient conditions for the approximate controllability of nonlinear fractional stochastic differential inclusions under the assumption that the corresponding linear system is approximately controllable. In addition, we establish the approximate controllability results for the fractional stochastic control system with infinite delay. The results are obtained with the help of the fixed-point theorem for multivalued operators and fractional calculus. Also, two examples are provided to illustrate the obtained theory.
TL;DR: In this paper, an asymmetric supercapacitor device based on the ultrathin mesoporous Co 3 O 4 nanosheets was fabricated and has shown promising energy densities of 136 Wh kg −1 ǫ at power density of 0.75kW −1.
TL;DR: This paper proposes a novel learning method for multimodal classification of AD/MCI, by fully exploring the relationships across both modalities and subjects, and achieves better classification performance compared with several state-of-the-art methods.
Abstract: Multimodal classification methods using different modalities of imaging and non-imaging data have recently shown great advantages over traditional single-modality-based ones for diagnosis and prognosis of Alzheimer's disease (AD), as well as its prodromal stage, i.e., mild cognitive impairment (MCI). However, to the best of our knowledge, most existing methods focus on mining the relationship across multiple modalities of the same subjects, while ignoring the potentially useful relationship across different subjects. Accordingly, in this paper, we propose a novel learning method for multimodal classification of AD/MCI, by fully exploring the relationships across both modalities and subjects. Specifically, our proposed method includes two subsequent components, i.e., label-aligned multi-task feature selection and multimodal classification. In the first step, the feature selection learning from multiple modalities are treated as different learning tasks and a group sparsity regularizer is imposed to jointly select a subset of relevant features. Furthermore, to utilize the discriminative information among labeled subjects, a new label-aligned regularization term is added into the objective function of standard multi-task feature selection, where label-alignment means that all multi-modality subjects with the same class labels should be closer in the new feature-reduced space. In the second step, a multi-kernel support vector machine (SVM) is adopted to fuse the selected features from multi-modality data for final classification. To validate our method, we perform experiments on the Alzheimer's Disease Neuroimaging Initiative (ADNI) database using baseline MRI and FDG-PET imaging data. The experimental results demonstrate that our proposed method achieves better classification performance compared with several state-of-the-art methods for multimodal classification of AD/MCI.
INAF1, University of Edinburgh2, Paris Diderot University3, Université Paris-Saclay4, Institut d'Astrophysique de Paris5, Space Telescope Science Institute6, University of Lisbon7, California Institute of Technology8, University of Strasbourg9, University of California, Santa Cruz10, University of Copenhagen11, University of Ferrara12, Anhui Normal University13, Nanjing University14
TL;DR: In this article, the first public release of photometric redshifts, galaxy rest-frame properties and associated magnification values in the cluster and parallel pointings of the first two Frontier Fields, Abell-2744 and MACS-J0416, is presented.
Abstract: We present the first public release of photometric redshifts, galaxy rest-frame properties and associated magnification values in the cluster and parallel pointings of the first two Frontier Fields, Abell-2744 and MACS-J0416. We exploit a multi-wavelength catalogue ranging from HST to ground-based K and Spitzer IRAC which is specifically designed to enable detection and measurement of accurate fluxes in crowded cluster regions. The multi-band information is used to derive photometric redshifts and physical properties of sources detected either in the H-band image alone or from a stack of four WFC3 bands. To minimize systematics median photometric redshifts are assembled from six different approaches to photo-z estimates. Their reliability is assessed through a comparison with available spectroscopic samples. State of the art lensing models are used to derive magnification values on an object-by-object basis by taking into account sources positions and redshifts. We show that photometric redshifts reach a remarkable ~3-5% accuracy. After accounting for magnification the H band number counts are found in agreement at bright magnitudes with number counts from the CANDELS fields, while extending the presently available samples to galaxies intrinsically as faint as H160~32-33 thanks to strong gravitational lensing. The Frontier Fields allow to probe the galaxy stellar mass distribution at 0.5-1.5 dex lower masses, depending on magnification, with respect to extragalactic wide fields, including sources at Mstar~ 10^7-10^8 Msun at z>5. Similarly, they allow the detection of objects with intrinsic SFRs>1dex lower than in the CANDELS fields reaching 0.1-1 Msun/yr at z~6-10. [abridged]
TL;DR: A two-photon ratiometric sensor at almost zero-background interference and bioimaging of tyrosinase activity have been demonstrated, suggesting the potential biomedical applications of the prepared functionalized Pdots.
Abstract: Semiconducting polymer dots (Pdots) with one-, two-photon excitation and dual-emission have been synthesized by coprecipitation of two conjugated polymers including poly(9,9-dioctylfluorenyl-2,7-diyl) (PFO) and poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-(1-cyanovinylene-1,4-phenylene)] (CN-PPV) and have been further functionalized with l-tyrosine methyl ester (Tyr-OMe) via electrostatic assembly for ratiometric fluorescent sensing and bioimaging of tyrosinase activity. Tyrosinase-catalyzed oxidation of Tyr-OMe effectively modulate the dual-emission fluorescence of PFO/CN-PPV@Tyr-OMe Pdots from orange to blue through a selective photoinduced electron transfer (PET) process. A two-photon ratiometric sensor at almost zero-background interference and bioimaging of tyrosinase activity have been demonstrated, suggesting the potential biomedical applications of the prepared functionalized Pdots.
TL;DR: The immunoassay was evaluated by analyzing simulate human serum sample, and the recoveries obtained were within 99.4-107.6% for PSA and 97.9-108.2% for AFP, indicating the immnuoassay could be applied to the simultaneous detection of AFP and PSA in human serum samples.
Abstract: In this work, a novel electrochemical immunoassay protocol has been reported for simultaneous determination of multiple tumor biomarkers based on DNA hybridization chain reaction (HCR) for signal amplification. Alpha-fetoprotein (AFP) and prostate specific antigen (PSA) were selected as model biomarkers. The immunoassay protocol contained primary antibodies immobilized on gold nanoparticles (Au NPs), secondary antibodies conjugated with DNA concatemer from HCR of primer, auxiliary probe, and signal probe labeled with signal molecules (methyleneblue (MB) and ferrocene (Fc)). In the presence of target biomarkers, the sandwich immunocomplex was formed between the primary antibodies and secondary antibodies bioconjugates carrying numerous signal molecules. As a result, two well-resolved reduction peaks, one was at −0.35 V (corresponding to MB) and other was at 0.33 V (corresponding to Fc; both vs SCE), were obtained in differential pulse voltammetry, and peak currents changed were related to the level of biom...
TL;DR: The xanthated Fe 3 O 4 -CS-GO was used to remove Cu(II) from aqueous solutions using an amidation reaction as discussed by the authors, which was attributed to the xanthation having abundant functional groups and could be regenerated using ethylene diamine tetraacetic acid, and could easily remove from a liquid using an external magnetic field.
TL;DR: In this article, a one dimensional core-shell hierarchical MnO2@NiMoO4 nanostructure is designed and prepared by a facile two-step hydrothermal method.
Abstract: A one dimensional core–shell hierarchical MnO2@NiMoO4 nanostructure is rationally designed and prepared by a facile two-step hydrothermal method This hybrid, along with porous carbon, is employed as an active material to fabricate flexible asymmetric supercapacitors, exhibiting a high capacitance of 1868 F g−1 at a scan rate of 10 mV s−1, super-long cycling life with a 1327% retention rate after 20 000 cycles, and super flexibility with no obvious changes of specific capacitance after bending to 30° to 150° (the corresponding radius of curvature is 45 mm to as small as 10 mm) Moreover, the supercapacitor is fabricated into a power system, in combination with a solar cell, to successfully supply electricity to light emitting diodes, showing its practical applications in portable energy storage devices
TL;DR: It was concluded that the release of P from the sediments with bioturbation to the pore water and the overlying water was promoted by the reductive dissolution of easily reducible Fe(oxyhydr)oxides due to the depletion of oxygen in the top sediments from bivalve respiration.
TL;DR: This method possesses sensitivity, reproducibility, and cost-effectiveness without labelling and separation and the use of a colorimetric method is more in line with the requirements of on-site detection and green chemistry.
Abstract: In this paper, a novel colorimetric method for the detection of alkaline phosphatase (ALP) and pyrophosphate (PPi) was designed based on a Cu2+–horseradish peroxidase (HRP)–3,3′,5,5′-tetra-methylbenzidine (TMB)–H2O2 system. In the presence of ALP, L-ascorbic acid-2-phosphate (AAP) could be hydrolyzed to ascorbic acid which could reduce Cu2+ to Cu+ to inhibit the enzymatic activity of HRP in the colorimetric system. The change in absorbance was found to be proportional to the ALP concentration with a linear detection range and a limit of detection of 5.4 mU mL−1. In the presence of PPi, because Cu2+ was chelated by PPi, the conversion of Cu(II) by AA was effectively inhibited. The color of the HRP–TMB–H2O2 system with Cu2+ showed blue. The HRP–TMB–H2O2 system with the Cu2+ colorimetric system could also detect PPi with a satisfying result. In summary, this method possesses sensitivity, reproducibility, and cost-effectiveness without labelling and separation and the use of a colorimetric method is more in line with the requirements of on-site detection and green chemistry.
TL;DR: In this paper, ultrafine nickel-copper carbonate hydroxide hierarchical nanowire arrays on copper foam are synthesized via a facile hydrothermal method without any adscititious surfactant and binder.
TL;DR: In this article, the authors proposed an integrated construct of the DCI and full mediating model, which added knowledge of the relationship between original image and potential tourist's visit intention, and showed that macro DCI has an indirect effect on visit intention through micro DCI.
Abstract: The concept of destination-country image (DCI) in tourism context is an integration of two constructs from different fields: country image from international marketing and destination image from tourism. Based on the concept of attitude in the theory of reasoned action and halo effect view, this study explains the macro and micro structures that support DCI, and tests the influence of the original DCI on visit intention of prospective tourists through three competing models. The results show that the macro DCI includes four dimensions: country character, country competence, people character and people competence; the micro DCI is composed of three dimensions: natural attraction, cultural attraction and service facility. Full mediating model is supported, which indicates that macro DCI has an indirect effect on visit intention through micro DCI. This study proposes an integrated construct of the DCI and full mediating model, which adds knowledge of the relationship between original image and potential tourist's visit intention.
TL;DR: A highly enantioselective 1,3-dipolar cycloaddition of imino esters with methyleneindolinones has been realized by using readily available thiourea-quaternary ammonium salts as phase-transfer catalysts, enabling efficient construction of a range of chiral spiro[pyrrolidin-3,3'-oxindoles] in good yields with excellent enantiOSElectivities under mild conditions.
TL;DR: In this article, the authors performed a simultaneous Maximum Likelihood PSF fit in the [0.5-2] and [2-7] energy bands of the 4Ms{\em Chandra} Deep Field South (CDFS) data at the position of the 34930 CANDELS H-band selected galaxies.
Abstract: Improving the capabilities of detecting faint X-ray sources is fundamental to increase the statistics on faint high-z AGN and star-forming galaxies. We performed a simultaneous Maximum Likelihood PSF fit in the [0.5-2] keV and [2-7] keV energy bands of the 4 Ms{\em Chandra} Deep Field South (CDFS) data at the position of the 34930 CANDELS H-band selected galaxies. For each detected source we provide X-ray photometry and optical counterpart validation. We validated this technique by means of a raytracing simulation. We detected a total of 698 X-ray point-sources with a likelihood $\mathcal{L}$$>$4.98 (i.e. $>$2.7$\sigma$). We show that the prior knowledge of a deep sample of Optical-NIR galaxies leads to a significant increase of the detection of faint (i.e. $\sim$10$^{-17}$ cgs in the [0.5-2] keV band) sources with respect to "blind" X-ray detections. By including previous X-ray catalogs, this work increases the total number of X-ray sources detected in the 4 Ms CDFS, CANDELS area to 793, which represents the largest sample of extremely faint X-ray sources assembled to date. Our results suggest that a large fraction of the optical counterparts of our X-ray sources determined by likelihood ratio actually coincides with the priors used for the source detection. Most of the new detected sources are likely star-forming galaxies or faint absorbed AGN. We identified a few sources sources with putative photometric redshift z$>$4. Despite the low number statistics and the uncertainties on the photo-z, this sample significantly increases the number of X--ray selected candidate high-z AGN.
TL;DR: This work uses theory and experiment to investigate the structural and plasmonic evolution of Ag-Ag2S nanoprisms during the sulfidation of Ag precursors, and finds that, depending on the reaction conditions, sulfidation occurs on the prism tips and/or the (111) surfaces, leading to a core(Ag)-anisotropic shell( Ag2S) prism nanostructure.
Abstract: Recently, Ag–Ag2S hybrid nanostructures have attracted a great deal of attention due to their enhanced chemical and thermal stability, in addition to their morphology- and composition-dependent tunable local surface plasmon resonances. Although Ag–Ag2S nanostructures can be synthesized via sulfidation of as-prepared anisotropic Ag nanoparticles, this process is poorly understood, often leading to materials with anomalous compositions, sizes, and shapes and, consequently, optical properties. In this work, we use theory and experiment to investigate the structural and plasmonic evolution of Ag–Ag2S nanoprisms during the sulfidation of Ag precursors. The previously observed red-shifted extinction of the Ag–Ag2S hybrid nanoprism as sulfidation occurs contradicts theoretical predictions, indicating that the reaction does not just occur at the prism tips as previously speculated. Our experiments show that sulfidation can induce either blue or red shifts in the extinction of the dipole plasmon mode, depending on...
TL;DR: In this paper, an exfoliated graphite paper (EGP) was used as a supported electrode for gold nanoparticles (AuNPs) electrodeposition to fabricate a sensor.
TL;DR: The results revealed that P. maackianus as a canopy-former mainly elongated its shoot length towards the water surface to compensate for the low light conditions, however, it became limited in severe low light stress conditions.
Abstract: To evaluate the relative importance of photosynthetic versus morphological adaptations of submersed macrophytes to low light intensity in lakes, rapid light curves (RLCs), morphological parameters, relative growth rate (RGR), clonal reproduction and abundance of two submersed macrophytes (Potamogeton maackianus and Vallisneria natans) were examined under 2.8%, 7.1%, 17.1% and 39.5% ambient light in a field and outdoor experimental study. The plants increased their initial slope of RLCs (α) and decreased their minimum saturating irradiance (Ek) and maximum relative electron transport rate (ETRm) of RLCs under low light stress, but V. natans was more sensitive in RLCs than P. maackianus. Accordingly, the RGR, plant height and abundance of P. maackianus were higher in the high light regimes (shallow water) but lower in the low light regimes than those of V. natans. At the 2.8% ambient light, V. natans produced ramets and thus fulfilled its population expansion, in contrast to P. maackianus. The results revealed that P. maackianus as a canopy-former mainly elongated its shoot length towards the water surface to compensate for the low light conditions, however, it became limited in severe low light stress conditions. V. natans as a rosette adapted to low light stress mainly through photosynthetic adjustments and superior to severely low light than shoot elongation.
INAF1, University of Lisbon2, University of Edinburgh3, Paris Diderot University4, University of Paris-Sud5, Institut d'Astrophysique de Paris6, Space Telescope Science Institute7, California Institute of Technology8, University of Strasbourg9, University of California, Santa Cruz10, Leiden University11, Anhui Normal University12, Nanjing University13
TL;DR: In this paper, a robust and repeatable procedure that uses the public codes Galapagos and Galfit to model and remove most of the light contribution from both the brightest cluster members as well as the ICL is presented.
Abstract: We present multiwavelength photometric catalogues (HST, Spitzer and Hawk-I K band) for the first two of the Frontier Fields, Abell2744 and MACSJ0416 (plus their parallel fields). To detect faint sources even in the central regions of the clusters, we develop a robust and repeatable procedure that uses the public codes Galapagos and Galfit to model and remove most of the light contribution from both the brightest cluster members as well as the ICL. We perform the detection on the HST H160 processed image to obtain a pure H-selected sample. We also add a sample of sources which are undetected in the H160 image but appear on a stacked infrared image. Photometry in the other HST bands is obtained using SExtractor, performed again on residual images after the Galfit procedure for foreground light removal. Photometry on the Hawk-I and IRAC bands has been obtained using our PSF-matching deconfusion code T-PHOT. A similar procedure, but without the need for the foreground light removal, is adopted for the Parallel fields. The procedure allows for the detection and the photometric measurements of ~2500 sources per field. We deliver and release complete photometric H-detected catalogues, with the addition of a complementary sample of infrared-detected sources. All objects have multiwavelength coverage including B to H HST bands, plus K band from Hawk-I, and 3.6 - 4.5 {\mu}m from Spitzer. Full and detailed treatment of photometric errors is included. We perform basic sanity checks on the reliability of our results. The multiwavelength catalogues are publicly available and are ready to be used for scientific purposes. Our procedures allows for the detection of outshined objects near the bright galaxies, which, coupled with the magnification effect of the clusters, can reveal extremely faint high redshift sources. Full analysis on photometric redshifts is presented in a companion Paper II. [abridged]
TL;DR: In light of the low cost and high earth abundance of Mn, the highly active Mn2 O3 is a promising candidate to be used as a cathode material in metal-air batteries and alkaline fuel cells.
Abstract: Preparing nonprecious metal catalysts with high activity in the oxygen reduction reaction (ORR) can promote the development of energy conversion devices. Support-free porous Mn2O3 was synthesized by a facile aerosol-spray-assisted approach (ASAA) and subsequent thermal treatment, and exhibited ORR activity that is comparable to commercial Pt/C The catalyst also exhibits notably higher activity than other Mn-based oxides, such as Mn3O4 and MnO2. The rotating ring disk electrode (RRDE) study indicates a typical 4-electron ORR pathway on Mn2O3. Furthermore, the porous Mn2O3 demonstrates considerable stability and a good methanol tolerance in alkaline media. In light of the low cost and high earth abundance of Mn, the highly active Mn2O3 is a promising candidate to be used as a cathode material in metal–air batteries and alkaline fuel cells.