bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tunable schottky barrier in blue phosphorus–graphene heterojunction with normal strain
Authors: Zhu Jiaduo , Zhang Jincheng , Hao Yue 
Published: July 2016

Abstract
The graphene–blue phosphorus van deer Waals (vDW) heterojunction was studied by using density functional theory. Our calculations reveal that the intrinsic electronic structure of blue phosphorus and graphene is well preserved and forms an n-type schottky barrier at equilibrium state. With increasing of normal tensile strain, the n-type is well kept. With compressive strain, the Dirac cone of graphene gradually shifts from conduction band minimum to valance band maximum of blue phosphorus, leading a turning of schottky barrier from n-type to p-type, which indicates an effective way to tune the electronic structure of vDW heterojunction.
First-principles study of d0 ferromagnetism in alkali-metal doped GaN
Authors: Zhang Yong 
Published: July 2016

Abstract
The d0 ferromagnetism in GaN has been studied based on density functional theory. Our results show that GaN with sufficient hole become spin-polarized. Alkali-metal doping can introduce holes in GaN. Among them, both of Li- and Na-doping induce ferromagnetism in GaN and Na-doped GaN behaves as half-metallic ferromagnet. Moreover, at a growth temperature of 2000 K under N-rich condition, both concentrations can exceed 18%, which is sufficient to produce detectable macroscopic magnetism in GaN. The Curie temperature of Li- and Na-doped GaN is estimated to be 304 and 740 K, respectively, which are well above room temperature.
Excimer laser annealing for low-voltage power MOSFET
Authors: Chen Yi , Okada Tatsuya , Noguchi Takashi , Mazzamuto Fulvio , Huet Karim 
Published: July 2016

Abstract
Excimer laser annealing of lumped beam was performed to form the P-base junction for high-performance low-voltage-power MOSFET. An equivalent shallow-junction structure for the P-base junction with a uniform impurity distribution is realized by adopting excimer laser annealing (ELA). The impurity distribution in the P-base junction can be controlled precisely by the irradiated pulse energy density and the number of shots of excimer laser. High impurity activation for the shallow junction has been confirmed in the melted phase. The application of the laser annealing technology in the fabrication process of a practical low-voltage trench gate MOSFET was also examined.
Evaluation of valence band top and electron affinity of SiO2 and Si-based semiconductors using X-ray photoelectron spectroscopy
Authors: Fujimura Nobuyuki , Ohta Akio , Makihara Katsunori , Miyazaki Seiichi 
Published: July 2016

Abstract
An evaluation method for the energy level of the valence band (VB) top from the vacuum level (VL) for metals, dielectrics, and semiconductors from the results of X-ray photoelectron spectroscopy (XPS) is presented for the accurate determination of the energy band diagram for materials of interest. In this method, the VB top can be determined by the energy difference between the onset of VB signals and the cut-off energy for secondary photoelectrons by considering the X-ray excitation energy (hν). The energy level of the VB top for three kinds of Si-based materials (H-terminated Si, wet-cleaned 4H-SiC, and thermally grown SiO2) has been investigated by XPS under monochromatized Al Kα radiation (hν = 1486.6 eV). We have also demonstrated the determination of the electron affinity for the samples by this measurement technique in combination with the measured and reported energy bandgaps (E
g).
Easy adjustment structure and method for realizing InP based polarization beam splitter via Pockels effect dependence on crystal orientation
Authors: Watanabe Kei , Nasu Yusuke , Ohiso Yoshitaka , Iga Ryuzo 
Published: July 2016

Abstract
We propose a novel adjustment structure and method for an InP-based polarization beam splitter/combiner by using the characteristic whereby the sign at the front of this term changes depending on the light propagation direction. To confirm the proposed principle of adjustment for our InP-based Mach–Zehnder interferometer polarization beam splitter/combiner, we fabricated a test sample that had an npin high-mesa waveguide structure with InGaAlAs/InAlAs multiple quantum wells. By using the test sample, we demonstrated the easy adjustment of an InP-based polarization beam splitter/combiner with the individual modulation of the TE and TM modes and showed that we can output TE/TM polarization at any port as desired.
External quantum efficiency and photovoltaic performance of silicon cells deposited with aluminum, indium, and silver nanoparticles
Authors: Ho Wen-Jeng , Hu Chia-Hua , Yeh Chien-Wu , Lee Yi-Yu 
Published: July 2016

Abstract
In this study, the plasmonic light scattering of aluminum (Al), indium (In), and sliver (Ag) nanoparticles (NPs) deposited on silicon solar cells was demonstrated. For comparison, the dimensions of all NPs were maintained at 17–25 nm with a coverage of approximately 30–40% through the control of film deposition and thermal annealing conditions. Absorbance and surface plasmon Raman scattering were used to examine the different localized surface plasmon resonances (LSPRs) of the proposed NPs. Optical reflectance, external quantum efficiency (EQE) response, and photovoltaic current density–voltage characteristics under AM 1.5G illumination were used to confirm the contribution of the plasmonic light scattering of the NPs. The conversion efficiencies of the solar cells with Al, In, and Ag NPs increased 1.21-, 1.23-, and 1.17-fold, respectively, compared with that of the reference bare Si solar cell. The EQE response and photovoltaic performance revealed that Al and In NPs produced broadband plasmonic light scattering and increased efficiency, far exceeding the results obtained using Ag NPs.
Family Business Governance: An Economics Interpretation and Research Implications in China
Authors: Li Zengquan , Zhou Guoliang , Guan Feng , Liu Junxia 
Published: July 2016

Abstract
Family businesses are a common organisational form worldwide. Issues such as forms of family business governance, reasons for adopting this specific form of governance, and the governance efficiency of family businesses have attracted extensive attention from economics researchers. After reviewing relevant studies, we find that Western scholars focus primarily on the governance efficiency of family businesses, and offer insufficient empirical evidence explaining the reasons for adopting various forms of governance. By contrast, Chinese scholars have conducted extensive research on listed and unlisted family businesses in China, presenting multi-perspective studies of the economic consequences of family governance for listed companies. Building on the basic ideas of property economics, we develop a theoretical framework for analysing family governance and use it to explore the possible influence of uniquely Chinese institutional variables on family business governance. The results can serve as a reference for future research on Chinese family businesses.
Rapid response of arbuscular mycorrhizal fungal communities to short-term fertilization in an alpine grassland on the Qinghai-Tibet Plateau
Authors: Xiang Xingjia , Gibbons Sean M. , He Jin-Sheng , Wang Chao , He Dan , Li Qian , Ni Yingying , Chu Haiyan 
Published: July 2016

Background:The Qinghai-Tibet Plateau (QTP) is home to the vast grassland in China. The QTP grassland ecosystem has been seriously degraded by human land use practices and climate change. Fertilization is used in this region to increase vegetation yields for grazers. The impact of long-term fertilization on plant and microbial communities has been studied extensively. However, the influence of short-term fertilization on arbuscular mycorrhizal fungal (AMF) communities in the QTP is largely unknown, despite their important functional role in grassland ecosystems.Methods:We investigated AMF community responses to three years of N and/or P addition at an experimental field site on the QTP, using the Illumina MiSeq platform (PE 300).Results:Fertilization resulted in a dramatic shift in AMF community composition and NP addition significantly increased AMF species richness and phylogenetic diversity. Aboveground biomass, available phosphorus, and NO3−were significantly correlated with changes in AMF community structure. Changes in these factors were driven by fertilization treatments. Thus, fertilization had a large impact on AMF communities, mediated by changes in aboveground productivity and soil chemistry.Discussion:Prior work has shown how plants often lower their reliance on AMF symbioses following fertilization, leading to decrease AMF abundance and diversity. However, our study reports a rise in AMF diversity with fertilization treatment. Because AMF can provide stress tolerance to their hosts, we suggest that extreme weather on the QTP may help drive a positive relationship between fertilizer amendment and AMF diversity.
A technique for inferring zonal irregularity drift from single‐station GNSS measurements of intensity (S4) and phase (σφ) scintillations
Authors: Carrano Charles S. , Groves Keith M. , Rino Charles L. , Doherty Patricia H. 
Published: July 2016

AbstractThe zonal drift of ionospheric irregularities at low latitudes is most commonly measured by cross‐correlating observations of a scintillating satellite signal made with a pair of closely spaced antennas. The Air Force Research Laboratory–Scintillation Network Decision Aid (AFRL‐SCINDA) network operates a small number of very high frequency (VHF) spaced‐receiver systems at low latitudes for this purpose. A far greater number of Global Navigation Satellite System (GNSS) scintillation monitors are operated by the AFRL‐SCINDA network (25–30) and the Low‐Latitude Ionospheric Sensor Network (35–50), but the receivers are too widely separated from each other for cross‐correlation techniques to be effective. In this paper, we present an alternative approach that leverages the weak scatter scintillation theory to infer the zonal irregularity drift from single‐station GNSS measurements of S4, σφ, and the propagation geometry. Unlike the spaced‐receiver technique, this approach requires assumptions regarding the height of the scattering layer (which introduces a bias in the drift estimates) and the spectral index of the irregularities (which affects the spread of the drift estimates about the mean). Nevertheless, theory and experiment suggest that the ratio of σφ to S4 is less sensitive to these parameters than it is to the zonal drift. We validate the technique using VHF spaced‐receiver measurements of zonal irregularity drift obtained from the AFRL‐SCINDA network. While the spaced‐receiver technique remains the preferred way to monitor the drift when closely spaced antenna pairs are available, our technique provides a new opportunity to monitor zonal irregularity drift using regional or global networks of widely separated GNSS scintillation monitors.
Influence of plankton community structure on the sinking velocity of marine aggregates
Authors: Bach L. T. , Boxhammer T. , Larsen A. , Hildebrandt N. , Schulz K. G. , Riebesell U. 
Published: July 2016

AbstractAbout 50 Gt of carbon is fixed photosynthetically by surface ocean phytoplankton communities every year. Part of this organic matter is reprocessed within the plankton community to form aggregates which eventually sink and export carbon into the deep ocean. The fraction of organic matter leaving the surface ocean is partly dependent on aggregate sinking velocity which accelerates with increasing aggregate size and density, where the latter is controlled by ballast load and aggregate porosity. In May 2011, we moored nine 25 m deep mesocosms in a Norwegian fjord to assess on a daily basis how plankton community structure affects material properties and sinking velocities of aggregates (Ø 80–400 µm) collected in the mesocosms' sediment traps. We noted that sinking velocity was not necessarily accelerated by opal ballast during diatom blooms, which could be due to relatively high porosity of these rather fresh aggregates. Furthermore, estimated aggregate porosity (Pestimated) decreased as the picoautotroph (0.2–2 µm) fraction of the phytoplankton biomass increased. Thus, picoautotroph‐dominated communities may be indicative for food webs promoting a high degree of aggregate repackaging with potential for accelerated sinking. Blooms of the coccolithophore Emiliania huxleyi revealed that cell concentrations of ~1500 cells/mL accelerate sinking by about 35–40%, which we estimate (by one‐dimensional modeling) to elevate organic matter transfer efficiency through the mesopelagic from 14 to 24%. Our results indicate that sinking velocities are influenced by the complex interplay between the availability of ballast minerals and aggregate packaging; both of which are controlled by plankton community structure.
A global quantification of compound precipitation and wind extremes
Authors: Martius Olivia , Pfahl Stephan , Chevalier Clément 
Published: July 2016

AbstractThe concomitant occurrence of extreme precipitation and winds can have severe impacts. Here this concomitant occurrence is quantified globally using ERA‐Interim reanalysis data. A logistic regression model is used to determine significant changes in the odds of precipitation extremes given a wind extreme that occurs on the same day, the day before, or the day after. High percentages of cooccurring wind and precipitation extremes are found in coastal regions and in areas with frequent tropical cyclones, with maxima of more than 50% of concomitant events. Strong regional‐scale variations in this percentage are related to the interaction of weather systems with topography resulting in Föhn winds, gap winds, and orographic drying and the structure and tracks of extratropical and tropical cyclones. The percentage of concomitant events increases substantially if spatial shifts by one grid point are taken into account. Such spatially shifted but cooccurring events are important in insurance applications.
Ionosphere‐magnetosphere energy interplay in the regions of diffuse aurora
Authors: Khazanov G. V. , Glocer A. , Sibeck D. G. , Tripathi A. K. , Detweiler L. G. , Avanov L. A. , Singhal R. P. 
Published: July 2016

AbstractBoth electron cyclotron harmonic (ECH) waves and whistler mode chorus waves resonate with electrons of the Earth's plasma sheet in the energy range from tens of eV to several keV and produce the electron diffuse aurora at ionospheric altitudes. Interaction of these superthermal electrons with the neutral atmosphere leads to the production of secondary electrons (E < 500–600 eV) and, as a result, leads to the activation of lower energy superthermal electron spectra that can escape back to the magnetosphere and contribute to the thermal electron energy deposition processes in the magnetospheric plasma. The ECH and whistler mode chorus waves, however, can also interact with the secondary electrons that are coming from both of the magnetically conjugated ionospheres after they have been produced by initially precipitated high‐energy electrons that came from the plasma sheet. After their degradation and subsequent reflection in magnetically conjugate atmospheric regions, both the secondary electrons and the precipitating electrons with high (E > 600 eV) initial energies will travel back through the loss cone, become trapped in the magnetosphere, and redistribute the energy content of the magnetosphere‐ionosphere system. Thus, scattering of the secondary electrons by ECH and whistler mode chorus waves leads to an increase of the fraction of superthermal electron energy deposited into the core magnetospheric plasma.
Short periodicities in low‐frequency plasma waves at Saturn
Authors: Carbary J. F. , Kurth W. S. , Mitchell D. G. 
Published: July 2016

AbstractShort‐period amplitude modulations (~60 min period) have been detected in the ~100 Hz plasma wave emissions observed by the Radio Plasma Wave Science instrument on the Cassini spacecraft in orbit around Saturn. These periodicities were detected throughout the mission from mid‐2004 to the present, and this is the first statistical study of them. The modulations are observed throughout the magnetosphere and can last from ~2 h to ~20 h, although the duration may be biased by spacecraft observing conditions. The periodicities are statistically much more likely to be seen at high latitudes, both north and south, and at local times between dusk and midnight. When corrected for latitude and local time, the occurrence frequency has declined in time since 2005. Considering all observations, the mean period of these events is 65.3 ± 20.7 min, with a peak (modal value) at 63.3 min. The period has no dependence on local time or latitude. Alfvén waves have interhemispheric transit times commensurate with the mean periods and should thus be considered principal candidates for their production.
High‐stress triaxial direct‐shear fracturing of Utica shale and in situ X‐ray microtomography with permeability measurement
Authors: Frash Luke P. , Carey J. William , Lei Zhou , Rougier Esteban , Ickes Timothy , Viswanathan Hari S. 
Published: July 2016

AbstractThe challenge of characterizing subsurface fluid flow has motivated extensive laboratory studies, yet fluid flow through rock specimens in which fractures are created and maintained at high‐stress conditions remains underinvestigated at this time. The studies of this type that do exist do not include in situ fracture geometry measurements acquired at stressed conditions, which would be beneficial for interpreting the flow behavior. Therefore, this study investigates the apparent permeability induced by direct‐shear fracture stimulation through Utica shale (a shale gas resource and potential caprock material) at high triaxial stress confinement and for the first time relates these values to simultaneously acquired in situ X‐ray radiography and microtomography images. Change in fracture geometry and apparent permeability was also investigated at additional reduced stress states. Finite element and combined finite‐discrete element modeling were used to evaluate the in situ observed fracturing process. Results from this study indicate that the increase in apparent permeability through fractures created at high‐stress (22.2 MPa) was minimal relative to the intact rock (less than 1 order of magnitude increase), while fractures created at low stress (3.4 MPa) were significantly more permeable (2 to 4 orders of magnitude increase). This study demonstrates the benefit of in situ X‐ray observation coupled with apparent permeability measurement to analyze fracture creation in the subsurface. Our results show that the permeability induced by fractures through shale at high stress can be minor and therefore favorable in application to CO2 sequestration caprock integrity but unfavorable for hydrocarbon recovery from unconventional reservoirs.
Comparative study of tectonic tremor locations: Characterization of slow earthquakes in Guerrero, Mexico
Authors: Maury J. , Ide S. , Cruz‐Atienza V. M. , Kostoglodov V. , González‐Molina G. , Pérez‐Campos X. 
Published: July 2016

AbstractDeep tectonic tremor in Guerrero, Mexico, has been observed using dense temporal seismic networks (i.e., the Meso‐American Subduction Experiment and Guerrero Gap Experiment (G‐GAP) arrays) during two different time periods. We apply a set of seismic waveform analysis methods to these data sets to constrain the locations of tremors and determine the associated moment tensors. First we detect and locate the tremors. Next, very low frequency (VLF) signals are identified by stacking waveform data during tremor bursts, and their moment tensors are determined. Finally, to better investigate the link between tremors and VLF earthquakes, we detect VLF events using a matched filtering algorithm to search continuous seismic records. None of the 11 VLF events detected by this method occurred in the absence of tremor bursts suggesting they are indeed part of the same phenomena. Unlike previous investigations, our results for the G‐GAP period reveal that downdip tremor activity (i.e., in the so‐called “sweet spot”) is segmented into two patches separated by 40 km in the along‐trench direction, indicating possible variations in the geometry of the plate interface and/or slab effective pressure. Moment tensors of VLF signals are consistent with shear slip on the near‐horizontal plate interface, but source depths are about 5 km deeper than the established plate interface. The slip directions of the VLF events are slightly (~10°) counterclockwise of the plate convergence direction, indicating that strain energy promoting left‐lateral strike‐slip motion may accumulate in the continental crust during the interseismic period.
Effects of sources, transport, and postdepositional processes on levoglucosan records in southeastern Tibetan glaciers
Authors: You Chao , Yao Tandong , Xu Baiqing , Xu Chao , Zhao Huabiao , Song Lili 
Published: July 2016

AbstractTibetan glaciers are substantially influenced by smoke aerosols derived from intensive biomass burning (BB) emissions in surrounding regions. However, knowledge regarding the impact of smoke aerosols on Tibetan glaciers is limited. Here we present levoglucosan records extracted from two southeastern Tibetan (SET) glaciers. We found that Zuoqiupu (ZQP) Glacier, situated on the windward side of the mountains, is more strongly affected by BB aerosols when compared with Cuopugou (CPG) Glacier on the leeward side. On ZQP Glacier, the highest levoglucosan concentration was detected at an elevation near the equilibrium line altitude. The injection height of smoke plumes and the actions of postdepositional processes on the glacier surface determined the distribution patterns of levoglucosan concentrations at different altitudes. Spatiotemporal variability in levoglucosan and black carbon distributions after deposition may be caused by the different source characteristics and by different postdepositional geochemical behaviors on the glacier surface. Intense wildfires can lead to extremely high concentrations (higher than 25 ng mL−1) of black carbon in ice near the surface of SET glaciers and can therefore play an important role in glacial melt during the premonsoon season.