bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of Kekulé and Non-Kekulé Structures in the Radical Character of Alternant Polycyclic Aromatic Hydrocarbons: A TAO-DFT Study
Authors: Yeh Chia-Nan , Chai Jeng-Da
Published: July 2016

We investigate the role of Kekulé and non-Kekulé structures in the radical character of alternant polycyclic aromatic hydrocarbons (PAHs) using thermally-assisted-occupation density functional theory (TAO-DFT), an efficient electronic structure method for the study of large ground-state systems with strong static correlation effects. Our results reveal that the studies of Kekulé and non-Kekulé structures qualitatively describe the radical character of alternant PAHs, which could be useful when electronic structure calculations are infeasible due to the expensive computational cost. In addition, our results support previous findings on the increase in radical character with increasing system size. For alternant PAHs with the same number of aromatic rings, the geometrical arrangements of aromatic rings are responsible for their radical character.
Graphene based sensors in the detection of glucose in saliva – a promising emerging modality to diagnose diabetes mellitus
Authors: Shanbhag Vagish Kumar L. , Prasad K. S.
Published: July 2016

No more needles – a new modality to detect saliva glucose with graphene and its derivatives is on the horizon.
An in-tether sulfilimine chiral center induces helicity in short peptides
Authors: Lin Huacan , Jiang Yixiang , Zhang Qingzhou , Hu Kuan , Li Zigang
Published: July 2016

A novel and effective helix-stabilizing strategy by introducing a precisely positioned S = NTs chiral centerviachloramine-T oxidation is demonstrated.
Electrocatalytic water oxidation by a macrocyclic Cu(ii) complex in neutral phosphate buffer
Authors: Yu Fengshou , Li Fei , Hu Jixiang , Bai Lichen , Zhu Yong , Sun Licheng
Published: July 2016

A robust molecular copper catalyst [Cu(TMC)(H2O)](NO3)2 was reported for electrocatalytic water oxidation in phosphate buffer. It exhibits superior activity to the ever reported homogeneous and heterogeneous copper-based WOCs under neutral conditions.
Hexagonal NiS nanobelts as advanced cathode materials for rechargeable Al-ion batteries
Authors: Yu Zhijing , Kang Zepeng , Hu Zongqian , Lu Jianhong , Zhou Zhigang , Jiao Shuqiang
Published: July 2016

NiS nanobelts served as cathode materials for Al-ion batteries based on an AlCl3/[EMIm]Cl ionic liquid electrolyte.
Modeling the surface chemistry of biomass model compounds on oxygen-covered Rh(100)
Authors: Caglar B. , Niemantsverdriet J. W. (Hans) , Weststrate C. J. (Kees-Jan)
Published: July 2016

This study provides a fundamental insight about how biomass-related compounds interact with metal surfaces in aqueous medium.
Systematic characterization of polycrystalline silica–carbonate helices
Authors: Nakouzi Elias , Knoll Pamela , Hendrix Kenzie B. , Steinbock Oliver
Published: July 2016

Biomorphs are complex, life-like structures that emerge from the precipitation of barium carbonate and amorphous silica in alkaline media.
Surface modification of adamantane-terminated gold nanoclusters using cyclodextrins
Authors: Yan Chunyang , Liu Chao , Abroshan Hadi , Li Zhimin , Qiu Renhua , Li Gao
Published: July 2016

The surface functionality of Au38S2(SAdm)20 nanoclusters (−SAdm = adamantanethiolate) in the presence of α-, β-, and γ-cyclodextrins (CDs) is studied.
A multifunctional extract from corn steep liquor: antioxidant and surfactant activities
Authors: Rodríguez-López L. , Vecino X. , Barbosa-Pereira L. , Moldes A. B. , Cruz J. M.
Published: July 2016

A bioactive extract with multifunctional properties can be obtained after subjecting corn steep liquor to liquid–liquid extraction and hydrothermal processes.
One-pot synthesis of a carbon supported bimetallic Cu–Ag NPs catalyst for robust catalytic hydroxylation of benzene to phenol by fast pyrolysis of biomass waste
Authors: Tian Ke , Liu Wu-Jun , Zhang Shun , Jiang Hong
Published: July 2016

The production of phenol in high yield and selectivity by direct catalytic hydroxylation of benzene (HOB) is challenging.
Cycloaddition of alkynes to diimino Mo3S4 cubane-type clusters: a combined experimental and theoretical approach
Authors: Pino-Chamorro Jose A. , Laricheva Yuliya A. , Guillamón Eva , Fernández-Trujillo M. Jesús , Bustelo Emilio , Gushchin Artem L. , Shmelev Nikita Y. , Abramov Pavel A. , Sokolov Maxim N. , Llusar Rosa , Basallote Manuel G. , Algarra Andrés G.
Published: July 2016

Newly synthesised molibdenum diimino clusters interact with alkynes leading to dithiolene species.
Chemically-doped graphene with improved surface plasmon characteristics: an optical near-field study
Authors: Zheng Zebo , Wang Weiliang , Ma Teng , Deng Zexiang , Ke Yanlin , Zhan Runze , Zou Qionghui , Ren Wencai , Chen Jun , She Juncong , Zhang Yu , Liu Fei , Chen Huanjun , Deng Shaozhi , Xu Ningsheng
Published: July 2016

The surface plasmon characteristics of chemically-doped graphene were systematically studied using the scanning near-field optical technique.
Polyacrylamide backbones for polyvalent bioconjugates using “post-click” chemistry
Authors: Nagao M. , Kurebayashi Y. , Seto H. , Takahashi T. , Suzuki T. , Hoshino Y. , Miura Y.
Published: July 2016

This paper reports the synthesis and application of acrylamide-type neoglycoconjugates interacting with practical targets.
Pyridine type zwitterionic polyurethane with both multi-shape memory effect and moisture-sensitive shape memory effect for smart biomedical application
Authors: Chen Shaojun , Mei Zhankui , Ren Huanhuan , Zhuo Haitao , Liu Jianhong , Ge Zaochuan
Published: July 2016

The pyridine type zwitterionic SMPUs have thermal-induced dual-SMEs, triple-SMEs and quadruple-SMEs, and moisture-sensitive SMEs. Zwitterionic segments improve the biocompatibility of pyridine containing SMPUs.
Aggregation induced emission of a cyanostilbene amphiphile as a novel platform for FRET-based ratiometric sensing of mercury ions in water
Authors: Wang Xiao , Gao Zongchun , Zhu Junlong , Gao Zhao , Wang Feng
Published: July 2016

A self-assembled FRET system on the basis of a cyanostilbene amphiphile has been constructed for ratiometric sensing of mercury ions in water.
Stimuli-responsive, biocompatible hydrogel derived from glycogen and poly(N-isopropylacrylamide) for colon targeted delivery of ornidazole and 5-amino salicylic acid
Authors: Patra Priyapratim , Rameshbabu Arun Prabhu , Das Dipankar , Dhara Santanu , Panda Asit Baran , Pal Sagar
Published: July 2016

A novel stimuli-responsive hydrogel (cl-Gly/pNIPAm) has been fabricated using biopolymer glycogen andN-isopropylacrylamide.
Rhodium/copper-cocatalyzed annulation of benzylamines with diazo compounds: access to fused isoquinolines
Authors: Wang Qiang , Li Xingwei
Published: July 2016

Benzylamines undergo C–H activation and aerobic coupling with diazo compounds, leading to the synthesis of fused isoquinolines. This occurs via a mild synergistic rhodium- and copper-catalyzed process.
Surface modification route to prepare novel polyamide@NH2_MIL-88B nanocomposite membranes for water treatment
Authors: Wang Luying , Duan Suxia , Fang Manquan , Liu Jing , He Jing , Li Jiding , Lei Jiandu
Published: July 2016

A surface modification route is used to fabricate a novel PA nanocomposite membrane with a PA coating on a NH2_MIL-88B interlayer.
The post treatment of composting leachate with a combination of ozone and persulfate oxidation processes
Authors: Soubh Alaa , Mokhtarani Nader
Published: July 2016

The simultaneous COD, color, and toxicity removal from biologically treated composting leachate, via an O3/persulfate oxidation process, was monitored.
The catalytic characteristics of NocB in nocathiacin biosynthesis from Nocardia sp. ATCC 202099
Authors: Wu Xuri , Huang Peiyu , Xue Yanjiu , Liu Weiying , Ma Min , Chen Yijun
Published: July 2016

NocB is compatible with nosiheptide gene cluster in nosiheptide-producing strain. NocB is a cytochrome P450-like monooxygenase in the biosyntheses of nocathiacin, which favors to catalyze the native tricyclic substrate.
Removal of perchlorate from water using a biofilm magnetic ion exchange resin: feasibility and effects of dissolved oxygen, pH and competing ions
Authors: Wu Min , Wang Shuaifeng , Gao Naiyun , Zhu Yanping , Li Lei , Niu Mingxing , Li Shuo
Published: July 2016

A biofilm magnetic ion exchange (BMIEX) resin was obtained by mixing a magnetic ion exchange (MIEX) resin with perchlorate-acclimated cultures and was first proposed to remove perchlorate from water.
CuS quantum dot modified carbon aerogel as an immobilizer for lithium polysulfides for high-performance lithium–sulfur batteries
Authors: Li Xueliang , Hu Kuan , Tang Ruwen , Zhao Kun , Ding Yunsheng
Published: July 2016

CuS quantum dot (QD) modified carbon aerogels were successfully prepared via a facile and scalable method to encapsulate sulfur and polysulfides into the hierarchical porous channel of lithium–sulfur batteries.
New insight into the alcohol induced conformational change and aggregation of the alkaline unfolded state of bovine β-lactoglobulin
Authors: Maity Sanhita , Sardar Subrata , Pal Sampa , Parvej Hasan , Chakraborty Jishnu , Halder Umesh Ch.
Published: July 2016

Here we report for first time the self-assembly of β-lg from its alkaline unfolded state.
A fluorometric assay for tyrosinase activity and its inhibitor screening based on graphene quantum dots
Authors: Zhao X. E. , Lei C. H. , Wang Y. H. , Qu F. , Zhu S. Y. , Wang H. , You J. M.
Published: July 2016

Pristine graphene quantum dots (GQDs) without any functionalization were used as probes to develop a sensitive and selective fluorescence sensing platform for the detection of tyrosinase (TYR) activity and its inhibitor screening for the first time.
Rationally leveraging mixotrophic growth of microalgae in different photobioreactor configurations for reducing the carbon footprint of an algal biorefinery: a techno-economic perspective
Authors: Subramanian Ganeshan , Yadav Geetanjali , Sen Ramkrishna
Published: July 2016

Experimental set-up to study mixotrophy in Chlorella vulgaris.
In situ growth of TiO2on TiN nanoparticles for non-noble-metal plasmonic photocatalysis
Authors: Li Chao , Yang Weiyi , Liu Lingmei , Sun Wuzhu , Li Qi
Published: July 2016

A novel plasmonic composite photocatalyst of TiN/TiO2demonstrated good visible-light-activated photocatalytic activity without noble metal components.
Laser-induced modification of dog-bone-like Au nanorods for accurate growth of well-defined cylindrical structures
Authors: Ma Jiaqi , Zhang Chong , Wang Dameng , Zhang Hua , Xu Linlin , Liu Xiangdong , Chen Ming
Published: July 2016

A novel and effective strategy for accurate growth of ultra-perfect cylindrical Au NRs is developed by laser-induced shape modification of dog-bone-like irregular Au rods, which can also guide the fabrication of Pt–Ag nano-islands on Au NRs.
Polypyrrole modified porous poly(ether sulfone) membranes with high performance for vanadium flow batteries
Authors: Yuan Zhizhang , Dai Qing , Zhao Yuyue , Lu Wenjing , Li Xianfeng , Zhang Huamin
Published: July 2016

Polypyrrole (PPY) modified porous poly(ether sulfone) (PPY/PES) membranes with excellent ion conductivity and high ion selectivity are prepared and employed in vanadium flow batteries (VFBs).
Electron transfer driven highly valent silver for chronic wound treatment
Authors: Yang K. , Liu J. , Shi H. G. , Zhang W. , Qu W. , Wang G. X. , Wang P. L. , Ji J. H.
Published: July 2016

This paper shows that reducing the dose of silver, additionally conferring electron transfer potential, could simultaneously achieve good biocompatibility and strong bactericidal ability without introducing extra chemical residuals for chronic wound treatment.
Scaffolding protein IQGAP1: an insulin-dependent link between caveolae and the cytoskeleton in primary human adipocytes?
Authors: Jufvas Åsa , Rajan Meenu R. , Jönsson Cecilia , Strålfors Peter , Turkina Maria V.
Published: July 2016

The ubiquitously expressed IQ motif-containing GTPase activating protein-1 (IQGAP1) is a scaffolding protein implicated in an array of cellular functions, in particular by binding to cytoskeletal elements and signaling proteins. A role of IQGAP1 in adipocytes has not been reported. We therefore investigated the cellular IQGAP1 interactome in primary human adipocytes. Immunoprecipitation and quantitative mass spectrometry identified caveolae and caveolae-associated proteins as the major IQGAP1 interactors alongside cytoskeletal proteins. We confirmed co-localization of IQGAP1 with the defining caveolar marker protein caveolin-1 by confocal microscopy and proximity ligation assay. Most interestingly, insulin enhanced the number of IQGAP1 interactions with caveolin-1 by five-fold. Moreover, we found a significantly reduced abundance of IQGAP1 in adipocytes from patients with type 2 diabetes compared with cells from nondiabetic control subjects. Both the abundance of IQGAP1 protein and mRNA were reduced, indicating a transcriptional defect in diabetes. Our findings suggest a novel role of IQGAP1 in insulin-regulated interaction between caveolae and cytoskeletal elements of the adipocyte, and that this is quelled in the diabetic state.
Phenotypical heterogeneity linked to adipose tissue dysfunction in patients with Type 2 diabetes
Authors: Barchetta Ilaria , Angelico Francesco , Del Ben Maria , Di Martino Michele , Cimini Flavia Agata , Bertoccini Laura , Polimeni Licia , Catalano Carlo , Fraioli Antonio , Del Vescovo Riccardo , Morini Sergio , Baroni Marco Giorgio , Cavallo Maria Gisella
Published: July 2016

Adipose tissue (AT) inflammation leads to increased free fatty acid (FFA) efflux and ectopic fat deposition, but whether AT dysfunction drives selective fat accumulation in specific sites remains unknown. The aim of the present study was to investigate the correlation between AT dysfunction, hepatic/pancreatic fat fraction (HFF, PFF) and the associated metabolic phenotype in patients with Type 2 diabetes (T2D). Sixty-five consecutive T2D patients were recruited at the Diabetes Centre of Sapienza University, Rome, Italy. The study population underwent clinical examination and blood sampling for routine biochemistry and calculation of insulin secretion [homoeostasis model assessment of insulin secretion (HOMA-β%)] and insulin-resistance [homoeostasis model assessment of insulin resistance (HOMA-IR) and adipose tissue insulin resistance (ADIPO-IR)] indexes. Subcutaneous (SAT) and visceral (VAT) AT area, HFF and PFF were determined by magnetic resonance. Some 55.4% of T2D patients had non-alcoholic fatty liver disease (NAFLD); they were significantly younger and more insulin-resistant than non-NAFLD subjects. ADIPO-IR was the main determinant of HFF independently of age, sex, HOMA-IR, VAT, SAT and predicted severe NAFLD with the area under the receiver operating characteristic curve (AUROC)=0.796 (95% confidence interval: 0.65–0.94, P=0.001). PFF was independently associated with increased total adiposity but did not correlate with AT dysfunction, insulin resistance and secretion or NAFLD. The ADIPO-IR index was capable of predicting NAFLD independently of all confounders, whereas it did not seem to be related to intrapancreatic fat deposition; unlike HFF, higher PFF was not associated with relevant alterations in the metabolic profile. In conclusion, the presence and severity of AT dysfunction may drive ectopic fat accumulation towards specific targets, such as VAT and liver, therefore evaluation of AT dysfunction may contribute to the identification of different risk profiles among T2D patients.
Sudden Sensorioneural Hearing Loss and Autoimmune Systemic Diseases
Authors: Rossini Bruno , Penido Norma , Munhoz Mario , Bogaz Eduardo , Curi Renata
Published: July 2016

Introduction Several authors have demonstrated the relationship between sudden sensorineural hearing loss (SNHL) and systemic autoimmune diseases (SAD). Immune-mediated SNHL can rarely present as unilateral sudden SNHL and manifests itself in the contralateral ear only after years. It presents clinical relevance for being one of the few SNHL that may be reversible given that early and appropriate treatment is applied.

Objective The objective of this study is to describe the clinical presentations and audiological findings from patients with idiopathic sudden SNHL and SAD associated with a probable diagnosis of immune-mediated SNHL. Furthermore, we strive to estimate the prevalence of SAD in patients with sudden SNHL.

Methods This is an observational retrospective cohort. We have selected and studied patients with SAD. Revision of available literature on scientific repositories.

Results We evaluated 339 patients with sudden SNHL. Among them, 13 (3.83%) patients suffered from SAD. Three patients had bilateral involvement, a total of 16 ears. We evaluate and describe various clinical, epidemiological, and audiological aspects of this sample.

Conclusion In our sample of patients with sudden SNHL, the prevalence of SAD was found relevant. The majority had tinnitus and dizziness concomitant hearing loss, unilateral involvement and had experienced profound hearing loss at the time of the installation. In spite of instituted treatment, most cases showed no improvement in audiometric thresholds. Apparently, patients with sudden SNHL and SAD have a more severe initial impairment, higher percentage of bilateral, lower response to treatment, and worse prognosis than patients with sudden SNHL of unknown etiology.
Active species delivered by dielectric barrier discharge filaments to bacteria biofilms on the surface of apple
Authors: Cheng He , Liu Xin , Lu Xinpei , Liu Dawei
Published: July 2016

The atmospheric pressure non-equilibrium plasma has shown a significant potential as a novel food decontamination technology. In this paper, we report a computational study of the intersection of negative streamer produced by air dielectric barrier discharge with bacteria biofilm on an apple surface. The structure, conductivities, and permittivities of bacteria biofilm have been considered in the Poisson's equations and transportation equations of charge and neutral species to realize self-consistent transportation of plasma between electrode and charging surfaces of apple. We find that the ionization near the biofilm facilitates the propagation of negative streamer when the streamer head is 1 mm from the biofilm. The structure of the biofilm results in the non-uniform distribution of ROS and RNS captured by flux and time fluence of these reactive species. The mean free path of charged species in μm scale permitted the plasma penetrate into the cavity of the biofilm, therefore, although the density of ROS and RNS decrease by 6–7 order of magnitude, the diffusion results in the uniform distribution of ROS and RNS inside the cavity during the pulse off period.
Applications of rigged Hilbert spaces in quantum mechanics and signal processing
Authors: Celeghini E. , Gadella M. , del Olmo M. A.
Published: July 2016

Simultaneous use of discrete and continuous bases in quantum systems is not possible in the context of Hilbert spaces, but only in the more general structure of rigged Hilbert spaces (RHS). In addition, the relevant operators in RHS (but not in Hilbert space) are a realization of elements of a Lie enveloping algebra and support representations of semigroups. We explicitly construct here basis dependent RHS of the line and half-line and relate them to the universal enveloping algebras of the Weyl-Heisenberg algebra and su(1, 1), respectively. The complete sub-structure of both RHS and of the operators acting on them is obtained from their algebraic structures or from the related fractional Fourier transforms. This allows us to describe both quantum and signal processing states and their dynamics. Two relevant improvements are introduced: (i) new kinds of filters related to restrictions to subspaces and/or the elimination of high frequency fluctuations and (ii) an operatorial structure that, starting from fix objects, describes their time evolution.
A DFT study of water adsorption on rutile TiO2 (110) surface: The effects of surface steps
Authors: Zheng Ting , Wu Chunya , Chen Mingjun , Zhang Yu , Cummings Peter T.
Published: July 2016

The associative and dissociative adsorption of water molecules at low-coverage situations on rutile TiO2 (110) surface with step defects was investigated by the density functional theory calculations. Structural optimization of the hydroxylated/hydrated configurations at step edges along the 11̄1 crystal directions and the dynamic process of water dissociation were discussed to get a better description of the water/TiO2 interface. Our results indicate that steps on the TiO2 (110) surface could be an active site for water dissociation. The results of geometry optimization suggest that the stability of hydroxylated configuration is largely dependent on the locations of the H species and the recombination of water molecules from hydroxyls is observed in the fully hydroxylated condition. However, these hydroxyls can be stabilized by the associatively absorbed water nearby by forming competitive intermolecular hydrogen bonds. The dynamics of water dissociation and hydrogen diffusion were studied by the first principles molecular dynamics simulation and our results suggest that the hydrogen released by water dissociation can be transferred among the adsorbates, such as the unsaturated oxygen atoms–H2O–hydroxyl (TiO–H2O–OH) complex at step edges, or gradually diffuses to the bulk water system in the form of hydronium (H3O+) at higher water coverage.
A variational approach to the liquid-vapor phase transition for hardcore ions in the bulk and in nanopores
Authors: Loubet Bastien , Manghi Manoel , Palmeri John
Published: July 2016

We employ a field-theoretical variational approach to study the behavior of ionic solutions in the grand canonical ensemble. To describe properly the hardcore interactions between ions, we use a cutoff in Fourier space for the electrostatic contribution of the grand potential and the Carnahan-Starling equation of state with a modified chemical potential for the pressure one. We first calibrate our method by comparing its predictions at room temperature with Monte Carlo results for excess chemical potential and energy. We then validate our approach in the bulk phase by describing the classical “ionic liquid-vapor” phase transition induced by ionic correlations at low temperature, before applying it to electrolytes at room temperature confined to nanopores embedded in a low dielectric medium and coupled to an external reservoir of ions. The ionic concentration in the nanopore is then correctly described from very low bulk concentrations, where dielectric exclusion shifts the transition up to room temperature for sufficiently tight nanopores, to high concentrations where hardcore interactions dominate which, as expected, modify only slightly this ionic “capillary evaporation.”
Novel high-pressure windows made of glass-like carbon for x-ray analysis
Authors: Testemale Denis , Prat Alain , Lahera Eric , Hazemann Jean-Louis
Published: July 2016

Original high-pressure glass-like carbon windows developed for x-ray spectroscopy applications are presented. The scientific and technological background of this new technical development is exposed, in particular the limitations of our existing beryllium windows in the context of x-ray absorption spectroscopy (XAS) measurements of solutions with very low solute concentrations at hydrothermal conditions (0.1-200 MPa, 30-600 °C). The benefits of glass-like carbon are exposed, notably its non-crystalline character, the absence of impurities which has been verified by micro-fluorescence laboratory measurements, and its non-toxicity which makes its machining safer. Finite elements mechanical calculations and experimental pressure tests were conducted to determine the pressure limits of windows with two different geometries: cylindrical (thickness 0.5 mm) and inversed-dome shape (thickness 0.5 mm at the tip of the dome). The former break at 150 MPa and the latter show no sign of rupture at 400 MPa. Recent XAS measurements conducted with the new dome shaped windows are presented to show the advantages of the design that allow for the detection of very low concentrations in the transmission mode (down to 30 ppm) and the acquisition of fluorescence XAS spectra in diluted solutions at high pressure. Eventually the perspectives of this original development are discussed.
A first principle particle mesh method for solution SAXS of large bio-molecular systems
Authors: Marchi Massimo
Published: July 2016

This paper will show that the solution small angle X-ray scattering (SAXS) intensity of globular and membrane proteins can be efficiently and accurately computed from molecular dynamics trajectories using 3D fast Fourier transforms (FFTs). A suitable particle meshing interpolation, similar to the one used in smooth particle mesh Ewald for electrostatic energies and forces, was combined with a uniform solvent density FFT padding scheme to obtain a convenient SAXS spectral resolution. The CPU time scaling of the method, as a function of system size, is highly favorable and its application to large systems such as solutions of solvated membrane proteins is computationally undemanding. Differently from other approaches, all contributions from the simulation cell are included. This means that the subtraction of the buffer from the solution scattering intensity is straightforward and devoid of artifact due to ad hoc definitions of proximal and distal solvent intensity contributions.
Optical study of the band structure of wurtzite GaP nanowires
Authors: Assali S. , Greil J. , Zardo I. , Belabbes A. , de Moor M. W. A. , Koelling S. , Koenraad P. M. , Bechstedt F. , Bakkers E. P. A. M. , Haverkort J. E. M.
Published: July 2016

We investigated the optical properties of wurtzite (WZ) GaP nanowires by performing photoluminescence (PL) and time-resolved PL measurements in the temperature range from 4 K to 300 K, together with atom probe tomography to identify residual impurities in the nanowires. At low temperature, the WZ GaP luminescence shows donor-acceptor pair emission at 2.115 eV and 2.088 eV, and Burstein-Moss band-filling continuum between 2.180 and 2.253 eV, resulting in a direct band gap above 2.170 eV. Sharp exciton α-β-γ lines are observed at 2.140–2.164–2.252 eV, respectively, showing clear differences in lifetime, presence of phonon replicas, and temperature-dependence. The excitonic nature of those peaks is critically discussed, leading to a direct band gap of ∼2.190 eV and to a resonant state associated with the γ-line ∼80 meV above the Γ8C conduction band edge.
Performance of Laser Megajoule’s x-ray streak camera
Authors: Zuber C. , Bazzoli S. , Brunel P. , Burillo M. , Fronty J. P. , Gontier D. , Goulmy C. , Moreau I. , Oudot G. , Rubbelynck C. , Soullié G. , Stemmler P. , Trosseille C.
Published: July 2016

A prototype of a picosecond x-ray streak camera has been developed and tested by Commissariat à l’Énergie Atomique et aux Énergies Alternatives to provide plasma-diagnostic support for the Laser Megajoule. We report on the measured performance of this streak camera, which almost fulfills the requirements: 50-μm spatial resolution over a 15-mm field in the photocathode plane, 17-ps temporal resolution in a 2-ns timebase, a detection threshold lower than 625 nJ/cm2 in the 0.05–15 keV spectral range, and a dynamic range greater than 100.
High temperature Hall measurement setup for thin film characterization
Authors: Adnane L. , Gokirmak A. , Silva H.
Published: July 2016

Hall measurement using the van der Pauw technique is a common characterization approach that does not require patterning of contacts. Measurements of the Hall voltage and electrical resistivity lead to the product of carrier mobility and carrier concentration (Hall coefficient) which can be decoupled through transport models. Based on the van der Paw method, we have developed an automated setup for Hall measurements from room temperature to ∼500 °C of semiconducting thin films of a wide resistivity range. The resistivity of the film and Hall coefficient is obtained from multiple current-voltage (I-V) measurements performed using a semiconductor parameter analyzer under applied constant “up,” zero, and “down” magnetic field generated with two neodymium permanent magnets. The use of slopes obtained from multiple I-Vs for the three magnetic field conditions offer improved accuracy. Samples are preferred in square shape geometry and can range from 2 mm to 25 mm side length. Example measurements of single-crystal silicon with known doping concentration show the accuracy and reliability of the measurement.
Precursor anion states in dissociative electron attachment to chlorophenol isomers
Authors: Kossoski F. , Varella M. T. do N.
Published: July 2016

We report a theoretical study on low-energy (<10 eV) elastic electron scattering from chlorophenol isomers, namely, para-chlorophenol (pCP), meta-chlorophenol (mCP), and ortho-chlorophenol (oCP). The calculations were performed with the Schwinger multichannel method with pseudopotentials, and analysis of the computed integral cross sections and virtual orbitals revealed one σCCl∗, one σOH∗, and three π∗ shape resonances. We show that electron capture into the two lower lying π∗ orbitals initiates dissociative processes that lead to the elimination of the chloride ion, accounting for the two overlapping peaks where this fragment was observed. Despite the relatively small differences on the energetics of the π∗ resonances, a major isomeric effect was found on their corresponding autodetachment lifetimes, which accounts for the observed increasing cross sections in the progression pCP < mCP < oCP. In particular, dissociation from the π1∗ anion of pCP is largely suppressed because of the unfavorable mixing with the σCCl∗ state. We found the intramolecular hydrogen bond present in oCP to have the opposite effects of stabilizing the σCCl∗ resonance and destabilizing the σOH∗ resonance. We also suggest that the hydrogen abstraction observed in chlorophenols and phenol actually takes place by a mechanism in which the incoming electron is directly attached to the dissociative σOH∗ orbital.
Interplay between the magnetic and magneto-transport properties of 3D interconnected nanowire networks
Authors: da Câmara Santa Clara Gomes Tristan , De La Torre Medina Joaquín , Velázquez-Galván Yenni G. , Martínez-Huerta Juan Manuel , Encinas Armando , Piraux Luc
Published: July 2016

We have explored the interplay between the magnetic and magneto-transport properties of 3D interconnected nanowire networks made of various magnetic metals by electrodeposition into nanoporous membranes with crossed channels and controlled topology. The close relationship between their magnetic and structural properties has a direct impact on their magneto-transport behavior. In order to accurately and reliably describe the effective magnetic anisotropy and anisotropic magnetoresistance, an analytical model inherent to the topology of 3D nanowire networks is proposed and validated. The feasibility to obtain magneto-transport responses in nanowire network films based on interconnected nanowires makes them very attractive for the development of mechanically stable superstructures that are suitable for potential technological applications.
Wireless energizing system for an automated implantable sensor
Authors: Swain Biswaranjan , Nayak Praveen P. , Kar Durga P. , Bhuyan Satyanarayan , Mishra Laxmi P.
Published: July 2016

The wireless drive of an automated implantable electronic sensor has been explored for health monitoring applications. The proposed system comprises of an automated biomedical sensing system which is energized through resonant inductive coupling. The implantable sensor unit is able to monitor the body temperature parameter and sends back the corresponding telemetry data wirelessly to the data recoding unit. It has been observed that the wireless power delivery system is capable of energizing the automated biomedical implantable electronic sensor placed over a distance of 3 cm from the power transmitter with an energy transfer efficiency of 26% at the operating resonant frequency of 562 kHz. This proposed method ensures real-time monitoring of different human body temperatures around the clock. The monitored temperature data have been compared with a calibrated temperature measurement system to ascertain the accuracy of the proposed system. The investigated technique can also be useful for monitoring other body parameters such as blood pressure, bladder pressure, and physiological signals of the patient in vivo using various implantable sensors.
Growth and device processing of hexagonal boron nitride epilayers for thermal neutron and deep ultraviolet detectors
Authors: Doan T. C. , Li J. , Lin J. Y. , Jiang H. X.
Published: July 2016

Solid-state neutron detectors with high performance are highly sought after for the detection of fissile materials. However, direct-conversion neutron detectors based on semiconductors with a measureable efficiency have not been realized. We report here the first successful demonstration of a direct-conversion semiconductor neutron detector with an overall detection efficiency for thermal neutrons of 4% and a charge collection efficiency as high as 83%. The detector is based on a 2.7 μm thick 10B-enriched hexagonal boron nitride (h-BN) epitaxial layer. The results represent a significant step towards the realization of practical neutron detectors based on h-BN epilayers. Neutron detectors based on h-BN are expected to possess all the advantages of semiconductor devices including wafer-scale processing, compact size, light weight, and ability to integrate with other functional devices.
Time-resolved analysis of the white photoluminescence from chemically synthesized SiCxOy thin films and nanowires
Authors: Tabassum Natasha , Nikas Vasileios , Ford Brian , Huang Mengbing , Kaloyeros Alain E. , Gallis Spyros
Published: July 2016

The study reported herein presents results on the room-temperature photoluminescence (PL) dynamics of chemically synthesized SiCxOy≤1.6 (0.19 < x < 0.6) thin films and corresponding nanowire (NW) arrays. The PL decay transients of the SiCxOy films/NWs are characterized by fast luminescence decay lifetimes that span in the range of 350–950 ps, as determined from their deconvoluted PL decay spectra and their stretched-exponential recombination behavior. Complementary steady-state PL emission peak position studies for SiCxOy thin films with varying C content showed similar characteristics pertaining to the variation of their emission peak position with respect to the excitation photon energy. A nearly monotonic increase in the PL energy emission peak, before reaching an energy plateau, was observed with increasing excitation energy. This behavior suggests that band-tail states, related to C-Si/Si-O-C bonding, play a prominent role in the recombination of photo-generated carriers in SiCxOy. Furthermore, the PL lifetime behavior of the SiCxOy thin films and their NWs was analyzed with respect to their luminescence emission energy. An emission-energy-dependent lifetime was observed, as a result of the modulation of their band-tail states statistics with varying C content and with the reduced dimensionality of the NWs.
Tuning back contact property via artificial interface dipoles in Si/organic hybrid solar cells
Authors: Wang Dan , Sheng Jiang , Wu Sudong , Zhu Juye , Chen Shaojie , Gao Pingqi , Ye Jichun
Published: July 2016

Back contact property plays a key role in the charge collection efficiency of c-Si/poly(3,4-ethylthiophene):poly(styrenesulfonate) hybrid solar cells (Si-HSCs), as an alternative for the high-efficiency and low-cost photovoltaic devices. In this letter, we utilize the water soluble poly (ethylene oxide) (PEO) to modify the Al/Si interface to be an Ohmic contact via interface dipole tuning, decreasing the work function of the Al film. This Ohmic contact improves the electron collection efficiency of the rear electrode, increasing the short circuit current density (Jsc). Furthermore, the interface dipoles make the band bending downward to increase the total barrier height of built-in electric field of the solar cell, enhancing the open circuit voltage (Voc). The PEO solar cell exhibits an excellent performance, 12.29% power conversion efficiency, a 25.28% increase from the reference solar cell without a PEO interlayer. The simple and water soluble method as a promising alternative is used to develop the interfacial contact quality of the rear electrode for the high photovoltaic performance of Si-HSCs.
Thermoelectric performance of co-doped SnTe with resonant levels
Authors: Zhou Min , Gibbs Zachary M. , Wang Heng , Han Yemao , Li Laifeng , Snyder G. Jeffrey
Published: July 2016

Some group III elements such as Indium are known to produce the resonant impurity states in IV-VI compounds. The discovery of these impurity states has opened up new ways for engineering the thermoelectric properties of IV-VI compounds. In this work, resonant states in SnTe were studied by co-doping with both resonant (In) and extrinsic (Ag, I) dopants. A characteristic nonlinear relationship was observed between the Hall carrier concentration (nH) and extrinsic dopant concentration (NI, NAg) in the stabilization region, where a linear increase of dopant concentration does not lead to linear response in the measured nH. Upon substituting extrinsic dopants beyond a certain amount, the nH changed proportionally with additional dopants (Ag, I) (the doping region). The Seebeck coefficients are enhanced as the resonant impurity is introduced, whereas the use of extrinsic doping only induces minor changes. Modest zT enhancements are observed at lower temperatures, which lead to an increase in the average zT values over a broad range of temperatures (300–773 K). The improved average zT obtained through co-doping indicates the promise of fine carrier density control in maximizing the favorable effect of resonant levels for thermoelectric materials.
In situ surface and interface study of crystalline (3×1)-O on InAs
Authors: Qin Xiaoye , Wang Wei-E. , Rodder Mark S. , Wallace Robert M.
Published: July 2016

The oxidation behavior of de-capped InAs (100) exposed to O2 gas at different temperatures is investigated in situ with high resolution of monochromatic x-ray photoelectron spectroscopy and low energy electron diffraction. The oxide chemical states and structure change dramatically with the substrate temperature. A (3 × 1) crystalline oxide layer on InAs is generated in a temperature range of 290–330 °C with a coexistence of In2O and As2O3. The stability of the crystalline oxide upon the atomic layer deposition (ALD) of HfO2 is studied as well. It is found that the generated (3 × 1) crystalline oxide is stable upon ALD HfO2 growth at 100 °C.
Solitary waves propagation described by Korteweg-de Vries equation in the granular chain with initial prestress
Authors: Yang Yang Yang , Liu Shi Wei , Yang Qiong , Zhang Zhen Bin , Duan Wen Shan , Yang Lei
Published: July 2016

The paper work relates to Nesterenko’s problem to further study the solitary wave when the strong external force acts on the granular chain. We also study the problem under the long-wavelength approximation and find that such kind of solitary wave in system with the initial prestress can be described by the Korteweg-de Vries (KdV) equation. It is found that the results of analytical and numerical are in an excellent agreement. Furthermore, we study the scattering of the KdV solitary wave in different granular materials both in theoretical and numerical methods. It is found that the numbers and the amplitudes of both the reflected and the transmitted waves depend not only on the amplitude of the incident solitary wave but also on the variations of both sides of the discontinuity such as the mass, Young’s modulus or radius of the grains.
Optical and electrical characterizations of a single step ion beam milling mesa devices of chloride passivated PbS colloidal quantum dots based film
Authors: Hechster Elad , Shapiro Arthur , Lifshitz Efrat , Sarusi Gabby
Published: July 2016

Colloidal Quantum Dots (CQDs) are of increasing interest, thanks to their quantum size effect that gives rise to their usage in various applications, such as biological tagging, solar cells and as the sensitizing layer of night vision devices. Here, we analyze the optical absorbance of chloride passivated PbS CQDs as well as revealing a correlation between their photoluminescence and sizes distribution, using theoretical models and experimental results from the literature. Next, we calculate the CQDs resistivity as a film. Although resistivity can be calculated from sheet resistance measurement using four point probes, such measurement is usually carried-out on the layer’s surface that in most cases has dangling bonds and surface states, which might affect the charges flow and modify the resistivity. Therefore; our approach, which was applied in this work, is to extract the actual resistivity from measurements that are performed along the film’s thickness (z-direction). For this intent, we fabricated gold capped PbS mesas devices using a single step Ion Beam Milling (IBM) process where we milled the gold and the PbS film continually, and then measured the vertical resistance. Knowing the mesas’ dimensions, we calculate the resistivity. To the best of our knowledge, no previous work has extracted, vertically, the resistivity of chloride passivated PbS CQDs using the above method.
A modified method of characteristics and its application in forward and inversion simulations of underwater explosion
Authors: Zhang Chengjiao , Li Xiaojie , Yang Chenchen
Published: July 2016

This paper introduces a modified method of characteristics and its application in forward and inversion simulations of underwater explosion. Compared with standard method of characteristics which is appropriate to homoentripic flow problem, the modified method can be also used to deal with isentropic flow problem such as underwater explosion. Underwater explosion of spherical TNT and composition B explosives are simulated by using the modified method, respectively. Peak pressures and flow field pressures are obtained, and they are coincident with those from empirical formulas. The comparison demonstrates the modified is feasible and reliable in underwater explosion simulation. Based on the modified method, inverse difference schemes and inverse method are introduced. Combined with the modified, the inverse schemes can be used to deal with gas-water interface inversion of underwater explosion. Inversion simulations of underwater explosion of the explosives are performed in water, and equation of state (EOS) of detonation product is not needed. The peak pressures from the forward simulations are provided as boundary conditions in the inversion simulations. Inversion interfaces are obtained and they are mainly in good agreement with those from the forward simulations in near field. The comparison indicates the inverse method and the inverse difference schemes are reliable and reasonable in interface inversion simulation.
Multi-level methods and approximating distribution functions
Authors: Wilson D. , Baker R. E.
Published: July 2016

Biochemical reaction networks are often modelled using discrete-state, continuous-time Markov chains. System statistics of these Markov chains usually cannot be calculated analytically and therefore estimates must be generated via simulation techniques. There is a well documented class of simulation techniques known as exact stochastic simulation algorithms, an example of which is Gillespie’s direct method. These algorithms often come with high computational costs, therefore approximate stochastic simulation algorithms such as the tau-leap method are used. However, in order to minimise the bias in the estimates generated using them, a relatively small value of tau is needed, rendering the computational costs comparable to Gillespie’s direct method. The multi-level Monte Carlo method (Anderson and Higham, Multiscale Model. Simul. 10:146–179, 2012) provides a reduction in computational costs whilst minimising or even eliminating the bias in the estimates of system statistics. This is achieved by first crudely approximating required statistics with many sample paths of low accuracy. Then correction terms are added until a required level of accuracy is reached. Recent literature has primarily focussed on implementing the multi-level method efficiently to estimate a single system statistic. However, it is clearly also of interest to be able to approximate entire probability distributions of species counts. We present two novel methods that combine known techniques for distribution reconstruction with the multi-level method. We demonstrate the potential of our methods using a number of examples.
Role of microbial reducing activity in antimony and arsenic release from an unpolluted wetland soil: a lab scale study using sodium azide as a microbial inhibiting agent
Authors: Rouwane Asmaa , Rabiet Marion , Bourven Isabelle , Grybos Malgorzata , Mallet Lucie , Guibaud Gilles
Published: July 2016

Environmental contextAntimony and arsenic are toxic elements occurring naturally in the environment. We found that arsenic release to water from an unpolluted wetland soil is related to microbial reducing activity only, whereas antimony can still be released when this activity is inhibited, suggesting the involvement of additional processes. The findings show that microbial/non-microbial mechanisms control arsenic and antimony release and can thereby impact water quality at wetland outlets. AbstractIn wetland soils, the mobility of geogenic metal(loid)s is usually associated with direct or indirect microbial-induced processes (solubilisation of mineral and organic components, pH induced desorption, competition effects, dissimilatory reduction). To identify the role of microbial reducing activity in As and Sb release, we conducted two series of soil incubations (sodium azide-treated (NaN3-T) and non-treated (NT)) in closed batches for 36 days. During the incubation period, we monitored the evolution of dissolved As, Sb, Mn, FeII, organic carbon (DOC), humic substances (HS) and proteins (PN) with their apparent molecular weight distribution (aMW) as well as pH, reduction potential (Eh) and alkalinity. Results showed that the release of As and Sb occurred when microbially reducing conditions prevailed (NT soil Eh ~0mV and FeII>40mg L–1) and was inhibited for As in the absence of microbial reducing activity (NaN3-T soil; Eh>250mV and Fe<1mg L–1). In contrast, Sb behaved differently since its release was only slowed down when microbially reducing conditions were inhibited. We concluded that soil microbial reducing activity fully controls the release of As and to a lesser extent that of Sb when NaN3 is used as a microbial inhibiting agent. Since Sb release and dissolved organic matter (DOM) solubilisation (NaN3-induced artefact) occurred simultaneously in the absence of microbially reducing conditions, we concluded that organic matter could be one key factor controlling Sb mobilisation in the given conditions, which is not the case for As.