bluuebunny/crossref_metadata_2025 huggingface dataset:
Graphene oxide-based electrochemical label-free detection of glycoproteins down to aM level using a lectin biosensor
Authors: Klukova L. , Filip J. , Belicky S. , Vikartovska A. , Tkac J.
Published: May 2016

A label-free ultrasensitive impedimetric biosensor with lectin immobilised on graphene oxide (GO) for the detection of glycoproteins from 1 aM is shown here.
Visualization of exhaled hydrogen sulphide on test paper with an ultrasensitive and time-gated luminescent probe
Authors: Zhang Ruilong , Liu Shijiang , Wang Jianping , Han Guangmei , Yang Linlin , Liu Bianhua , Guan Guijian , Zhang Zhongping
Published: May 2016

Luminescent chemosensors for hydrogen sulfide (H2S) are of great interest because of the close association of H2S with our health.
An efficient core–shell fluorescent silica nanoprobe for ratiometric fluorescence detection of pH in living cells
Authors: Fu Jingni , Ding Changqin , Zhu Anwei , Tian Yang
Published: May 2016

An efficient core–shell fluorescent silica nanoprobe was developed for ratiometric fluorescence imaging of pH variation in ouabain-treated HeLa cells.
Leveraging ultraviolet photodissociation and spectroscopy to investigate peptide and protein three-dimensional structure with mass spectrometry
Authors: Hendricks Nathan G. , Julian Ryan R.
Published: May 2016

Recent advances in mass spectrometry and lasers have facilitated the development of novel experiments combining the benefits of both technologies.
A SnOx–brookite TiO2 bilayer electron collector for hysteresis-less high efficiency plastic perovskite solar cells fabricated at low process temperature
Authors: Kogo Atsushi , Ikegami Masashi , Miyasaka Tsutomu
Published: May 2016

Thin plastic film-based CH3NH3PbI3−xClx perovskite solar cells were fabricated at low process temperature using a bilayer comprising an amorphous SnOx and mesoporous brookite TiO2 as electron collectors.
The advent of multilayer antimonene nanoribbons with room temperature orange light emission
Authors: Tsai Hsu-Sheng , Chen Chia-Wei , Hsiao Ching-Hung , Ouyang Hao , Liang Jenq-Horng
Published: May 2016

Multilayer antimonene nanoribbons with room temperature orange light emission uniformly distributed on InSb were synthesized by the plasma-assisted process.
Luminescence responsive intracluster rearrangements of gold(i)–silver(i) clusters triggered by acetonitrile
Authors: Liu Xiao-Yun , Yang Yang , Lei Zhen , Guan Zong-Jie , Wang Quan-Ming
Published: May 2016

Reversible interconversion between two cluster isomers with distinct luminescence colors can be triggered by acetonitrile in the solid state.
Electrocatalytic reduction of CO2 using Mn complexes with unconventional coordination environments
Authors: Rao Gyandshwar Kumar , Pell Wendy , Korobkov Ilia , Richeson Darrin
Published: May 2016

New complexes, Mn{κ3-[2,6-{Ph2PNMe}2(NC5H3)]}(CO)3+Br− (1+Br−) and MnBr{κ2-(Ph2P)NMe(NC5H4)}(CO)3 (2), are reported and present new ligand environments for CO2 electrocatalytic reduction to CO.
Supramolecular protection from the enzymatic tyrosine phosphorylation in a polypeptide
Authors: Faggi Enrico , Pérez Yolanda , Luis Santiago V. , Alfonso Ignacio
Published: May 2016

Two pseudopeptidic cages bind the EYE peptide motif of poly(EY) in buffered water, as shown by NMR and fluorescence spectroscopy. This supramolecular interaction protects the Tyr residues from the enzymatic phosphorylation by PTK.
The importance of the Lewis base in lithium mediated metallation and bond cleavage reaction of allyl amines and allyl phosphines
Authors: Blair V. L. , Stevens M. A. , Thompson C. D.
Published: May 2016

Reactions of analogous N-allyl and P-allyl moietys with nBuLi and different Lewis donors was investigated resulting in contrasting reactivity. The N-allyl moieties favor deprotonation products while the P-allyl system result in competing P-allyl bond cleavage.
Atomic scale mobility of the volatile fission products Xe, Kr and I in cubic SiC
Authors: Cooper M. W. D. , Kelly S. , Bertolus M.
Published: May 2016

The migration barriers for the vacancy-assisted migration of fission products in 3C-SiC are reported and analysed in the context of the five frequency model, which enables one to calculate an effective diffusion coefficient from elementary mechanisms.
Cooperative enhancement versus additivity of two-photon-absorption cross sections in linear and branched squaraine superchromophores
Authors: Ceymann Harald , Rosspeintner Arnulf , Schreck Maximilian H. , Mützel Carina , Stoy Andreas , Vauthey Eric , Lambert Christoph
Published: May 2016

Our investigation of the nonlinear optical properties of a series of oligomeric squaraine dyes showed enhanced cross sections for linear oligomers but only additivity for branched systems.
Atomic elucidation of the cyclodextrin effects on DDT solubility and biodegradation
Authors: Ren Baiping , Zhang Mingzhen , Gao Huipeng , Zheng Jie , Jia Lingyun
Published: May 2016

Different binding modes between DDT and CDs explain why only α-CD can promote the bioavailability and biodegradation of DDT by simultaneously increasing its aqueous solubility and membrane interaction.
Photosensitized reactions initiated by 6-carboxypterin: singlet and triplet reactivity
Authors: Tinel L. , Rossignol S. , Ciuraru R. , Dumas S. , George C.
Published: May 2016

The photophysical and photochemical properties of 6-carboxypterin, a model compound for the pterin derivatives present at the sea surface microlayer, were studied and its singlet and triplet reactivity toward halides and selected organics demonstrated.
SnPhPc phthalocyanines with dianion Pc2− and radical trianion Pc˙3− macrocycles: syntheses, structures, and properties
Authors: Konarev Dmitri V. , Kuzmin Alexey V. , Nakano Yoshiaki , Khasanov Salavat S. , Ishikawa Manabu , Otsuka Akihiro , Yamochi Hideki , Saito Gunzi , Lyubovskaya Rimma N.
Published: May 2016

Phenyl substituted tin(iv) phthalocyanine in [SnPhPc2−]+(BPh4)−·C6H14 (1) and [SnPhPc˙3−]0·C6H4Cl2 (2) have been obtained. While the SnPhPc in 1 is charged +1, that of 2 is a neutral radical containing Pc˙3−.
Tailored design of ruthenium molecular catalysts with 2,2′-bypyridine-6,6′-dicarboxylate and pyrazole based ligands for water oxidation
Authors: Daniel Quentin , Wang Lei , Duan Lele , Li Fusheng , Sun Licheng
Published: May 2016

A series of tailor-designed Ruthenium based water oxidation catalysts have been synthesized. By fine tuning of the catalyst structure, the turnover frequency was increased up to 500 s−1and the stability over 6000 turnovers.
Structural dynamics of photochemical reactions probed by time-resolved photoelectron spectroscopy using high harmonic pulses
Authors: Iikubo Ryo , Sekikawa Taro , Harabuchi Yu , Taketsugu Tetsuya
Published: May 2016

Femtosecond ring-opening dynamics of 1,3-cyclohexadiene (CHD) in gas phase upon two-photon excitation at 400 nm (=3.1 eV) was investigated by time-resolved photoelectron spectroscopy using 42 nm (=29.5 eV) high harmonic photons probing the dynamics of the lower-lying occupied molecular orbitals (MOs), which are the fingerprints of the molecular structure. After 500 fs, the photoelectron intensity of the MO constituting the CC sigma bond (σCC) of CHD was enhanced, while that of the MO forming the C–C sigma bond (σCC) of CHD was decreased. The changes in the photoelectron spectra suggest that the ring of CHD opens to form a 1,3,5-hexatriene (HT) after 500 fs. The dynamics of the σCC and σCC bands between 200 and 500 fs reflects the ring deformation to a conical intersection between the 21A and 11A potential energy surfaces prior to the ring-opening reaction.
Investigation on the suitability of ablated carbon as an internal standard in laser ablation ICP-MS of polymers
Authors: Deiting D. , Börno F. , Hanning S. , Kreyenschmidt M. , Seidl T. , Otto M.
Published: May 2016

The ablation crater shapes and the correlation between ablated carbon and13C-ICP-MS signals of twenty-one virgin polymers with laser ablation were investigated.
Personalized nutrition diagnostics at the point-of-need
Authors: Lee Seoho , Srinivasan Balaji , Vemulapati Sasank , Mehta Saurabh , Erickson David
Published: May 2016

Advancements in LOC technologies are enabling personalized nutrition diagnostics at the point-of-need.
Printing of stretchable silk membranes for strain measurements
Authors: Ling Shengjie , Zhang Qiang , Kaplan David L. , Omenetto Fiorenzo , Buehler Markus J. , Qin Zhao
Published: May 2016

A high stretchable silk strain gauge made by direct printing.
Microfluidic generation of hollow Ca-alginate microfibers
Authors: Meng Zhi-Jun , Wang Wei , Xie Rui , Ju Xiao-Jie , Liu Zhuang , Chu Liang-Yin
Published: May 2016

Controllable hollow Ca-alginate microfibers are continuously fabricated from microfluidic four-aqueous-phase flow templates, which contain a buffer flow between Ca2+ and alginate flows for prevention of rapid Ca2+/alginate crosslinking.
Characterizing the molecular phenotype of an Atp7aT985Iconditional knock in mouse model for X-linked distal hereditary motor neuropathy (dHMNX)
Authors: Perez-Siles Gonzalo , Grant Adrienne , Ellis Melina , Ly Carolyn , Kidambi Aditi , Khalil Mamdouh , Llanos Roxana M. , Fontaine Sharon La , Strickland Alleene V. , Züchner Stephan , Bermeo Sandra , Neist Elysia , Brennan-Speranza Tara C. , Takata Reinaldo I. , Speck-Martins Carlos E. , Mercer Julian F. B. , Nicholson Garth A. , Kennerson Marina L.
Published: May 2016

We have generated an Atp7a conditional knock in mouse model of dHMNX expressingAtp7aT985I, the orthologue of the humanATP7AT994Iidentified in dHMNX patients.
Dipole effects on the formation of molecular junctions
Authors: Tanimoto Sachie , Tsutsui Makusu , Yokota Kazumichi , Taniguchi Masateru
Published: May 2016

Measuring the tunneling current is a promising way of identifying individual molecules in a liquid, wherein the electric field in an electrode gap plays an important role on restricting the conformational degrees of freedom through electrostatic interactions with the molecular dipoles.
A smart multifunctional drug delivery nanoplatform for targeting cancer cells
Authors: Hoop M. , Mushtaq F. , Hurter C. , Chen X.-Z. , Nelson B. J. , Pané S.
Published: May 2016

Nanomachines incorporating stimuli-responsive chitosan hydrogels are engineered as a platform for multifunctional and wirelessly guided drug delivery to cancer cells.
Organocatalytic asymmetric Michael addition of α-alkylidene succinimides to nitrostyrenes
Authors: Zhao Bo-Liang , Zhang Dongxiang , Liu Lei , Du Da-Ming
Published: May 2016

A squaramide-catalyzed asymmetric Michael addition of α-alkylidene succinimides to nitrostyrenes for the synthesis of chiral succinimide derivatives was described.
Functional lipids based on [12]aneN3 and naphthalimide as efficient non-viral gene vectors
Authors: Gao Yong-Guang , Alam Uzair , Tang Quan , Shi You-Di , Zhang Ying , Wang Ruibing , Lu Zhong-Lin
Published: May 2016

Small organic non-viral gene vectors with the structural combinations of (aliphatic chain)–naphthalimide–[12]aneN3 (11a, b) and naphthalimide–(aliphatic chain)–[12]aneN3 (12a–c) were synthesized and fully characterized.
From racemic precursors to fully stereocontrolled products: one-pot synthesis of chiral α-amino lactones and lactams
Authors: You Zhi-Hao , Chen Ying-Han , Liu Yan-Kai
Published: May 2016

All possible stereoisomeric products of chiral α-amino lactones and lactams are discretely provided from racemic precursors under one-pot conditions.
Synthesis of symmetrical methylene-bridged imidazoheterocycles using DMSO as methylene source under metal-free conditions
Authors: Liu Ping , Shen Ziyan , Yuan Yao , Sun Peipei
Published: May 2016

Methylene-bridged imidazo-heterocycles were synthesized by a H3PO4-promoted bridging methylenation of imidazopyridines or similar heterocycles, in which DMSO was used as the carbon source.
Rhodium-catalyzed asymmetric arylation of N- and O-containing cyclic aldimines: facile and efficient access to highly optically active 3,4-dihydrobenzo[1,4]oxazin-2-ones and dihydroquinoxalinones
Authors: Zhang Xu , Xu Bin , Xu Ming-Hua
Published: May 2016

A highly enantioselective Rh-catalyzed arylation of benzoxazinones and quinoxalinones with arylboroxines was realized for the first time by employing a simple sulfur-olefin as the ligand.
The influence of oxygen functional groups on gas-sensing properties of reduced graphene oxide (rGO) at room temperature
Authors: Wang X. , Li X. , Zhao Y. , Chen Y. , Yu J. , Wang J.
Published: May 2016

Three methods were used to prepare reduced graphene oxide (rGO) with various ratios of oxygen functional groups, such as –OOH, –OH and CO, to study their effects on the NO2 sensing properties at room temperature.
A systematic study on the Cadiot–Chodkiewicz cross coupling reaction for the selective and efficient synthesis of hetero-diynes
Authors: Chinta Bhavani Shankar , Baire Beeraiah
Published: May 2016

99% selectivity for cross coupling. Excellent yields (upto 94%). Low basic reaction medium, high functional group tolerance. Use of green solvent water.
Green synthesis of polyureas from CO2 and diamines with a functional ionic liquid as the catalyst
Authors: Wang Peixue , Ma Xiangyuan , Li Qinghe , Yang Benqun , Shang Jianpeng , Deng Youquan
Published: May 2016

The synthesis of polyureas from CO2 and diamines with a functional ionic liquid as the catalyst.
Surface properties of amphiphilic carbon nanotubes and study of their applicability as basic catalysts
Authors: Ramirez-Barria C. , Guerrero-Ruiz A. , Castillejos-López E. , Rodríguez-Ramos I. , Durand J. , Volkman J. , Serp P.
Published: May 2016

Amphiphilic hybrid carbon nanotubes (CNTs) containing a hydrophobic undoped section connected to a hydrophilic N-doped segment were synthesized. Their application as basic catalysts in the aldol condensation of furfural and acetone was tested.
Environmentally friendly BaxSr2−xTiFeO6double perovskite with enhanced thermopower for high temperature thermoelectric power generation
Authors: Roy Pinku , Waghmare Vikram , Maiti Tanmoy
Published: May 2016

SrTiO3based double perovskites, BaxSr2−xTiFeO6(BSTF) compositions showed very large thermo-power (S) for the application of high temperature thermoelectric power generation.
A facile and chemoselective synthesis of 1,4-benzodiazepin-2-ones and dienyl thiazolidin-4-ones
Authors: Kuila Bilash , Kumar Yogesh , Mahajan Dinesh , Kumar Kapil , Singh Prabhpreet , Bhargava Gaurav
Published: May 2016

A chemoselective synthesis of novel 1,4-benzodiazepin-2-ones and dienyl thiazolidin-4-one carboxylates in excellent yields by ring transformation reactions of functionally decorated 2-azetidin-3-thiazolidin-4-ones is reported.
Single excited state intramolecular proton transfer (ESIPT) chemodosimeter based on rhodol for both Hg2+and OCl−: ratiometric detection with live-cell imaging
Authors: Manna Abhishek , Sarkar Debasish , Goswami Shyamaprosad , Quah Ching Kheng , Fun Hoong-Kun
Published: May 2016

We have synthesised a ratiometric fluorescence chemodosimeter,STBR, for the detection of Hg2+and OCl−in one platform over other cations, anions and oxidants in aqueous solution.
Facile hydrogen atom transfer to iron(iii) imido radical complexes supported by a dianionic pentadentate ligand
Authors: Spasyuk Denis M. , Carpenter Stephanie H. , Kefalidis Christos E. , Piers Warren E. , Neidig Michael L. , Maron Laurent
Published: May 2016

Facile hydrogen atom transfer from toluene.
NiFe2O4–CNT composite: an efficient electrocatalyst for oxygen evolution reactions in Li–O2batteries guided by computations
Authors: Zhang Xin , Zhang Xu , Wang Xin-Gai , Xie Zhaojun , Zhou Zhen
Published: May 2016

Guided by computations, we designed a NiFe2O4/CNT composite, which displayed high oxygen evolution activity in Li–O2batteries.
Transition metal carbide-based materials: synthesis and applications in electrochemical energy storage
Authors: Xiao Ying , Hwang Jang-Yeon , Sun Yang-Kook
Published: May 2016

Transition metal carbides have attracted vast interest over the past years due to their appealing properties such as high conductivity, high chemical stability and thermal stability.
Aromatic π–π driven supergelation, aggregation induced emission and columnar self-assembly of star-shaped 1,2,4-oxadiazole derivatives
Authors: Pathak Suraj Kumar , Pradhan Balaram , Gupta Ravindra Kumar , Gupta Monika , Pal Santanu Kumar , Achalkumar Ammathnadu S.
Published: May 2016

Effect of the number of flexible peripheral tails on the self-assembly of star-shaped molecules.
Double sparse learning model for speech emotion recognition
Authors: Zong Yuan , Zheng Wenming , Cui Zhen , Li Qiang
Published: May 2016

A double sparse learning (DSL) model with a pyramid structure‐based feature extraction scheme to handle speech emotion recognition (SER) problem is proposed. The key novelty of the method is that the proposed DSL model is able to take into consideration two scales of the pyramid structure‐based features for selecting the features which have great contributions to SER. Extensive experiments on eNTERFACE and AFEW emotion databases to evaluate the method are conducted. The experimental results demonstrate that, compared with some recent competitive methods, DSL with the pyramid structure‐based feature extraction scheme has a more promising performance in dealing with the SER task.
Broadband RCS reduction using a novel double layer chessboard AMC surface
Authors: Mighani M. , Dadashzadeh G.
Published: May 2016

A novel broadband chessboard surfaces with double layer structure to reduce the radar cross‐section (RCS) of an object is presented. By combining two artificial magnetic conductor (AMC) cells and a novel structure, 73% frequency bandwidth of −10 dB RCS reduction compared with a metallic plate has been obtained. In order to increase the bandwidth in chessboard structures, boards with high thickness are required, cheaper boards’ thickness are limited. An RO4003 board on an air substrate has been used. This technique, in addition to accommodating the designer with a new parameter, decreases the costs and increases the bandwidth greatly and also simulation results and measurements are in good correspondence.
Impact of device technology on cosmic ray failures in power modules
Authors: Scheuermann Uwe , Schilling Uwe
Published: May 2016

More than 20 years ago, the phenomenon of cosmic ray induced failures in power electronic devices was first reported. High energy particles can generate ‘single event burnout’ failures in power devices in blocking state, i.e. the device loses its blocking capability without any precursor on a nanosecond time scale. Whilst the root cause of the failure can rarely be identified after an explosion of the inverter, the statistical probability of cosmic ray failures can be determined from experiment, so that this random failure rate can be well predicted for power electronic systems. The considerable impact of device architecture will be demonstrated by experimental results for freewheeling diodes, showing that the CAL diode is very robust with regard to cosmic ray failures.
Improved inertial control for permanent magnet synchronous generator wind turbine generators
Authors: Wu Ziping , Gao Wenzhong , Wang Xiao , Kang Moses , Hwang Min , Kang Yong Cheol , Gevogian Vahan , Muljadi Eduard
Published: May 2016

With increasing integrations of large‐scale systems based on permanent magnet synchronous generator wind turbine generators (PMSG‐WTGs), the overall inertial response of a power system will tend to deteriorate as a result of the decoupling of rotor speed and grid frequency through the power converter as well as the scheduled retirement of conventional synchronous generators. Thus, PMSG‐WTGs can provide value to an electric grid by contributing to the system's inertial response through the inherent kinetic energy stored in their rotating masses and fast power converter control. In this study, an improved inertial control method based on the maximum power point tracking operation curve is introduced to enhance the overall frequency support capability of PMSG‐WTGs in the case of large supply–demand imbalances. Moreover, this method is implemented in the CART2‐PMSG integrated model in MATLAB/Simulink to investigate its impact on the wind turbine's structural loads during the inertial response process. Simulation results indicate that the proposed method can effectively reduce the frequency nadir, arrest the rate of change of frequency, and alleviate the secondary frequency dip while imposing no negative impact on the major mechanical components of the wind turbine.
Coordinated dispatch of networked energy storage systems for loading management in active distribution networks
Authors: Wang Dongxiao , Meng Ke , Luo Fengji , Coates Colin , Gao Xiaodan , Dong Zhao Yang
Published: May 2016

System overloading is becoming a critical issue in distribution system due to outdated infrastructure and growing electricity demand. Although renewable‐based distributed generation is a promising solution to relieve this issue, its intermittency and uncertainty impose significant challenges on system operations. This study attempts to coordinate networked energy storage systems (NESSs) to manage network loading in distribution networks. The NESS can act as a buffer to absorb surplus energy during high generation periods and serve the demand during peak load periods. A consensus‐based dispatch strategy is proposed to coordinate NESSs. Through limited communication among neighbouring NESSs, required active power curtailment is shared. The mathematical formulation of a state‐of‐charge weighting factor is introduced to improve the efficiency of NESSs. A sensitivity study is also conducted to demonstrate the performance of the proposed strategy.
Entlassung so wie immer
Authors: Rybak Christian
Published: May 2016

Rezepte für Patienten ausstellen? Heilmittel verordnen? Gemach, gemach. KBV, DKG und GKV müssen noch den Rahmenvertrag aushandeln.
Hygiene: Ab jetzt Chefsache
Authors: König Romy
Published: May 2016

Immer mehr Klinikchefs stolpern über Hygieneskandale. Kein Wunder: Allzu oft herrscht das Delegationsprinzip. Sicher ist nur, wer sich selbst ein Bild über Strukturen und Schnittstellen macht.
Investitionsstau: Helfer in der Not
Authors: Mewis Dirk
Published: May 2016

Die Finanzmisere der Kommunen gefährdet dringend notwendige Investitionen von Kliniken. Wer im Verdrängungskampf bestehen will, muss attraktiver werden, doch weder öffentliche Mittel noch Eigenkapital reichen aus. Der Weg zu externem Geld ist steinig, aber Finanzinstitute versprechen Lösungen.
Zwei Bauvorhaben – zwei Kreditpläne: So klappt es mit der Bank im Haus
Authors: Kreutzer Simone , Bommel Sabine
Published: May 2016

Bauen ist für viele Kliniken heute Pflicht, wenn es darum geht, Zukunftsfähigkeit und Standort-entwicklung zu sichern. Gleichzeitig ist die Finanzlage nicht selten angespannt. Die Andree Consult GmbH begleitet aktuell zwei Krankenhäuser bei der Kreditplanung für ihre Bauvorhaben. Für beide Objekte fand sich nach Analyse der unterschiedlichen Ausgangssituationen die passende Lösung.
Nicolas Schulwitz: Alles auf eine Karte
Authors: Schünemann Christian
Published: May 2016

Bei einer Hochzeit hörte Nicolas Schulwitz (32) von einer zündenden Idee: Wie wäre es, mit einer Online-Video-Sprechstunde das Verhältnis von Arzt und Patient zu revolutionieren? Gesagt, getan. Schulwitz kündigte einen sicheren Job und gründete das Start-up-Unternehmen Patientus.
Large eddy simulations of a transcritical round jet submitted to transverse acoustic modulation
Authors: Gonzalez-Flesca M. , Schmitt T. , Ducruix S. , Candel S.
Published: May 2016

This article reports numerical computations of a turbulent round jet of transcritical fluid (low temperature nitrogen injected under high pressure conditions) surrounded by the same fluid at rest under supercritical conditions (high temperature and high pressure) and submitted to transverse acoustic modulations. The numerical framework relies on large eddy simulation in combination with a real-gas description of thermodynamics and transport properties. A stationary acoustic field is obtained by modulating the normal acoustic velocity at the lateral boundaries of the computational domain. This study specifically focuses on the interaction of the jet with the acoustic field to investigate how the round transcritical jet changes its shape and mixes with the surrounding fluid. Different modulation amplitudes and frequencies are used to sweep a range of conditions. When the acoustic field is established in the domain, the jet length is notably reduced and the jet is flattened in the spanwise direction. Two regimes of oscillation are identified: for low Strouhal numbers a large amplitude motion is observed, while for higher Strouhal numbers the jet oscillates with a small amplitude around the injector axis. The minimum length is obtained for a Strouhal number of 0.3 and the jet length increases with increasing Strouhal numbers after reaching this minimum value. The mechanism of spanwise deformation is shown to be linked with dynamical effects resulting from reduction of the pressure in the transverse direction in relation with increased velocities on the two sides of the jet. A propagative wave is then introduced in the domain leading to similar effects on the jet, except that a bending is also observed in the acoustic propagation direction. A kinematic model, combining hydrodynamic and acoustic contributions, is derived in a second stage to represent the motion of the jet centerline. This model captures details of the numerical simulations quite well. These various results can serve to interpret observations made on more complex flow configurations such as coaxial jets or jet flames formed by coaxial injectors.
Mutual neutralization of He+ with the anions Cl−, Br−, I−, and SF6−
Authors: Wiens Justin P. , Shuman Nicholas S. , Miller Thomas M. , Viggiano Albert A.
Published: May 2016

Mutual neutralization (MN) rate coefficients kMN for He+ with the anions Cl−, Br−, I−, and SF6− are reported from 300 to 500 K. The measured rate coefficients may contain a contribution from transfer ionization, i.e., double ionization of the anion. The large rate coefficient for He+ + SF6− (2.4 × 10−7 cm3 s−1 at 300 K) is consistent with earlier polyatomic MN results found to have a reduced mass dependence of μ−1/2. Neutralization of He+ by the atomic halides follows the trend observed earlier for Ne+, Ar+, Kr+, and Xe+ neutralized by atomic halides, kMN (Cl−) < kMN (Br−) < kMN (I−). Only an upper limit could be measured for the neutralization of He+ by Cl−. Predictions of the rate coefficients from a previously proposed simple model of atomic–atomic MN results are consistent with the present He+–halide rate coefficients. The temperature dependences are modestly negative for Br− and I−, while that for SF6− is small or negligible.
The circadian rhythm induced by the heterogeneous network structure of the suprachiasmatic nucleus
Authors: Gu Changgui , Yang Huijie
Published: May 2016

In mammals, the master clock is located in the suprachiasmatic nucleus (SCN), which is composed of about 20 000 nonidentical neuronal oscillators expressing different intrinsic periods. These neurons are coupled through neurotransmitters to form a network consisting of two subgroups, i.e., a ventrolateral (VL) subgroup and a dorsomedial (DM) subgroup. The VL contains about 25% SCN neurons that receive photic input from the retina, and the DM comprises the remaining 75% SCN neurons which are coupled to the VL. The synapses from the VL to the DM are evidently denser than that from the DM to the VL, in which the VL dominates the DM. Therefore, the SCN is a heterogeneous network where the neurons of the VL are linked with a large number of SCN neurons. In the present study, we mimicked the SCN network based on Goodwin model considering four types of networks including an all-to-all network, a Newman-Watts (NW) small world network, an Erdös-Rényi (ER) random network, and a Barabási-Albert (BA) scale free network. We found that the circadian rhythm was induced in the BA, ER, and NW networks, while the circadian rhythm was absent in the all-to-all network with weak cellular coupling, where the amplitude of the circadian rhythm is largest in the BA network which is most heterogeneous in the network structure. Our finding provides an alternative explanation for the induction or enhancement of circadian rhythm by the heterogeneity of the network structure.
The effect of Prandtl number on mixing in low Reynolds number Kelvin-Helmholtz billows
Authors: Rahmani M. , Seymour B. R. , Lawrence G. A.
Published: May 2016

The effect of Prandtl number on mixing in temporally evolving Kelvin-Helmholtz (KH) instabilities at low to moderate Reynolds numbers is studied through direct numerical simulation. We distinguish between the mixing induced by the primary billow and the mixing generated by three-dimensional motions by performing each simulation in two and three dimensions. The results indicate that the time evolution of the rate of two- and three-dimensional mixing through different stages of the life cycle of KH flow is significantly influenced by the Prandtl number. As the Prandtl number increases, the final amount of mixing increases for Reynolds that are too low to support active three-dimensional motions. This trend is the opposite in sufficiently high Reynolds number KH flows that can overcome viscous effects and develop significant three-dimensional instabilities. While the mixing generated in the two-dimensional flows, uniform in the span-wise direction, is not significantly dependent on the Prandtl number, the turbulent mixing induced by three-dimensional motions is a function of the Prandtl number. We observe a steady increase in the total amount of mixing for buoyancy Reynolds numbers above 7, consistent with the results of Shih et al. [“Parameterization of turbulent fluxes and scales using homogeneous sheared stably stratified turbulence simulations,” J. Fluid Mech. 525, 193-214 (2005)]. Both maximum instantaneous and cumulative mixing efficiencies exhibit a decreasing trend with increasing Prandtl number. We compare the dependence of the mixing efficiency on Prandtl number to previous studies.
Invited Article: Quantitative imaging of explosions with high-speed cameras
Authors: McNesby Kevin L. , Homan Barrie E. , Benjamin Richard A. , Boyle Vincent M. , Densmore John M. , Biss Matthew M.
Published: May 2016

The techniques presented in this paper allow for mapping of temperature, pressure, chemical species, and energy deposition during and following detonations of explosives, using high speed cameras as the main diagnostic tool. This work provides measurement in the explosive near to far-field (0-500 charge diameters) of surface temperatures, peak air-shock pressures, some chemical species signatures, shock energy deposition, and air shock formation.
An apparatus to measure frictional, anelastic, and viscous behavior in ice at temperate and planetary conditions
Authors: McCarthy C. , Savage H. M. , Koczynski T. , Nielson M. A.
Published: May 2016

In this paper, we describe a cryogenic, servo-controlled biaxial friction apparatus designed to measure the deformational behaviors of ice. The apparatus is specifically designed to accurately achieve and measure the low differential stresses applicable to deforming ice on earth and on icy satellites. We can apply loads in the range ∼2–1800 kPa and velocities up to 4 mm/s, with resolution of 39 Pa and 0.7 μm, respectively. Precise temperature control, measurement, and insulation allow testing at constant temperature (from −2 to −30 °C) for prolonged periods of time. The apparatus is tested with various plastics as well as with polycrystalline ice samples and the results are consistent with previously published values. Critical components of the instrument are described along with examples of data collection schemes and preliminary results. The flexibility of the design allows for both glaciological and planetary applications over a range of deformational behaviors including friction, anelastic, and viscous.
Bottom-up coarse-grained models with predictive accuracy and transferability for both structural and thermodynamic properties of heptane-toluene mixtures
Authors: Dunn Nicholas J. H. , Noid W. G.
Published: May 2016

This work investigates the promise of a “bottom-up” extended ensemble framework for developing coarse-grained (CG) models that provide predictive accuracy and transferability for describing both structural and thermodynamic properties. We employ a force-matching variational principle to determine system-independent, i.e., transferable, interaction potentials that optimally model the interactions in five distinct heptane-toluene mixtures. Similarly, we employ a self-consistent pressure-matching approach to determine a system-specific pressure correction for each mixture. The resulting CG potentials accurately reproduce the site-site rdfs, the volume fluctuations, and the pressure equations of state that are determined by all-atom (AA) models for the five mixtures. Furthermore, we demonstrate that these CG potentials provide similar accuracy for additional heptane-toluene mixtures that were not included their parameterization. Surprisingly, the extended ensemble approach improves not only the transferability but also the accuracy of the calculated potentials. Additionally, we observe that the required pressure corrections strongly correlate with the intermolecular cohesion of the system-specific CG potentials. Moreover, this cohesion correlates with the relative “structure” within the corresponding mapped AA ensemble. Finally, the appendix demonstrates that the self-consistent pressure-matching approach corresponds to minimizing an appropriate relative entropy.
Critical coupling using the hexagonal boron nitride crystals in the mid-infrared range
Authors: Wu Jipeng , Wang Hengliang , Jiang Leyong , Guo Jun , Dai Xiaoyu , Xiang Yuanjiang , Wen Shuangchun
Published: May 2016

We theoretically demonstrate the perfect absorption phenomena in the hexagonal boron nitride (hBN) crystals in the mid-infrared wavelength ranges by means of critical coupling with a one-dimensional photonic crystal spaced by the air. Different from the polymer absorbing layer composed by a metal-dielectric composite film, the hyperbolic dispersion characteristics of hBN can meet the condition of critical coupling and achieve the total absorption in the mid-infrared wavelength ranges. However, the critical coupling phenomenon can only appear in the hBN crystals with the type II dispersion. Moreover, we discuss the influence of the thickness of hBN, the incident angle, and the thickness and permittivity of the space dielectric on the total absorption. Ultimately, the conditions for absorption enhancement and the optimization methods of perfect absorption are proposed, and the design rules for a totally absorbing system under the different conditions are achieved.
Development of a magnetized coaxial plasma gun for compact toroid injection into the C-2 field-reversed configuration device
Authors: Matsumoto T. , Sekiguchi J. , Asai T. , Gota H. , Garate E. , Allfrey I. , Valentine T. , Morehouse M. , Roche T. , Kinley J. , Aefsky S. , Cordero M. , Waggoner W. , Binderbauer M. , Tajima T.
Published: May 2016

A compact toroid (CT) injector was developed for the C-2 device, primarily for refueling of field-reversed configurations. The CTs are formed by a magnetized coaxial plasma gun (MCPG), which consists of coaxial cylindrical electrodes and a bias coil for creating a magnetic field. First, a plasma ring is generated by a discharge between the electrodes and is accelerated by Lorenz self-force. Then, the plasma ring is captured by an interlinkage flux (poloidal flux). Finally, the fully formed CT is ejected from the MCPG. The MCPG described herein has two gas injection ports that are arranged tangentially on the outer electrode. A tungsten-coated inner electrode has a head which can be replaced with a longer one to extend the length of the acceleration region for the CT. The developed MCPG has achieved supersonic CT velocities of ∼100 km/s. Plasma parameters for electron density, electron temperature, and the number of particles are ∼5 × 1021 m−3, ∼40 eV, and 0.5–1.0 × 1019, respectively.
Sub-wavelength InAs quantum dot micro-disk lasers epitaxially grown on exact Si (001) substrates
Authors: Wan Yating , Li Qiang , Liu Alan Y. , Chow Weng W. , Gossard Arthur C. , Bowers John E. , Hu Evelyn L. , Lau Kei May
Published: May 2016

Subwavelength micro-disk lasers (MDLs) as small as 1 μm in diameter on exact (001) silicon were fabricated using colloidal lithography. The micro-cavity gain medium incorporating five-stacked InAs quantum dot layers was grown on a high crystalline quality GaAs-on-V-grooved-Si template with no absorptive intermediate buffers. Under continuous-wave optical pumping, the MDLs on silicon exhibit lasing in the 1.2-μm wavelength range with low thresholds down to 35 μW at 10 K. The MDLs compare favorably with devices fabricated on native GaAs substrates and state-of-the-art work reported elsewhere. Feasibility of device miniaturization can be projected by size-dependent lasing characteristics. The results show a promising path towards dense integration of photonic components on the mainstream complementary metal–oxide–semiconductor platform.
Extent of hydrogen coverage of Si(001) under chemical vapor deposition conditions from ab initio approaches
Authors: Rosenow Phil , Tonner Ralf
Published: May 2016

The extent of hydrogen coverage of the Si(001) c(4 × 2) surface in the presence of hydrogen gas has been studied with dispersion corrected density functional theory. Electronic energy contributions are well described using a hybrid functional. The temperature dependence of the coverage in thermodynamic equilibrium was studied computing the phonon spectrum in a supercell approach. As an approximation to these demanding computations, an interpolated phonon approach was found to give comparable accuracy. The simpler ab initio thermodynamic approach is not accurate enough for the system studied, even if corrections by the Einstein model for surface vibrations are considered. The on-set of H2 desorption from the fully hydrogenated surface is predicted to occur at temperatures around 750 K. Strong changes in hydrogen coverage are found between 1000 and 1200 K in good agreement with previous reflectance anisotropy spectroscopy experiments. These findings allow a rational choice for the surface state in the computational treatment of chemical reactions under typical metal organic vapor phase epitaxy conditions on Si(001).
Accuracy and computational efficiency of real-time subspace propagation schemes for the time-dependent density functional theory
Authors: Russakoff Arthur , Li Yonghui , He Shenglai , Varga Kalman
Published: May 2016

Time-dependent Density Functional Theory (TDDFT) has become successful for its balance of economy and accuracy. However, the application of TDDFT to large systems or long time scales remains computationally prohibitively expensive. In this paper, we investigate the numerical stability and accuracy of two subspace propagation methods to solve the time-dependent Kohn-Sham equations with finite and periodic boundary conditions. The bases considered are the Lánczos basis and the adiabatic eigenbasis. The results are compared to a benchmark fourth-order Taylor expansion of the time propagator. Our results show that it is possible to use larger time steps with the subspace methods, leading to computational speedups by a factor of 2–3 over Taylor propagation. Accuracy is found to be maintained for certain energy regimes and small time scales.
Ion aggregation in high salt solutions. V. Graph entropy analyses of ion aggregate structure and water hydrogen bonding network
Authors: Choi Jun-Ho , Cho Minhaeng
Published: May 2016

Dissolved ions in water tend to form polydisperse ion aggregates such as ion pairs, relatively compact ion clusters, and even spatially extended ion networks with increasing salt concentration. Combining molecular dynamics simulation and graph theoretical analysis methods, we recently studied morphological structures of ion aggregates with distinctively different characteristics. They can be distinguished from each other by calculating various spectral graph theoretical properties such as eigenvalues and eigenvectors of adjacency matrices of ion aggregates and water hydrogen-bonding networks, minimum path lengths, clustering coefficients, and degree distributions. Here, we focus on percolation and graph entropic properties of ion aggregates and water hydrogen-bonding networks in high salt solutions. Ion network-forming K+ and SCN− ions at high concentrations show a percolating behavior in their aqueous solutions, but ion cluster-forming ions in NaCl solutions do not show such a transition from isolated ion aggregates to percolating ion-water mixture morphology. Despite that the ion aggregate structures are strikingly different for either cluster- or network-forming ions in high salt solutions, it is interesting that the water structures remain insensitive to the electrostatic properties, such as charge densities and polydentate properties, of dissolved ions, and morphological structures of water H-bonding networks appear to be highly robust regardless of the nature and concentration of salt. We anticipate that the present graph entropy analysis results would be of use in understanding a variety of anomalous behaviors of interfacial water around biomolecules as well as electric conductivities of high electrolyte solutions.
Atomistic modeling of phonon transport in turbostratic graphitic structures
Authors: Mao Rui , Chen Yifeng , Kim Ki Wook
Published: May 2016

Thermal transport in turbostratic graphitic systems is investigated by using an atomistic analytical model based on the 4th-nearest-neighbor force constant approximation and a registry-dependent interlayer potential. The developed model is shown to produce an excellent agreement with the experimental data and ab initio results in the calculation of bulk properties. Subsequent analysis of phonon transport in combination with the Green's function method illustrates the significant dependence of key characteristics on the misorientation angle, clearly indicating the importance of this degree of freedom in multi-stacked structures. Selecting three angles with the smallest commensurate unit cells, the thermal resistance is evaluated at the twisted interface between two AB stacked graphite. The resulting values in the range of 35 × 10−10 K m2/W to 116 × 10−10 K m2/W are as large as those between two dissimilar material systems such as a metal and graphene. The strong rotational effect on the cross-plane thermal transport may offer an effective means of phonon engineering for applications such as thermoelectric materials.
Multimode delta-E effect magnetic field sensors with adapted electrodes
Authors: Zabel Sebastian , Reermann Jens , Fichtner Simon , Kirchhof Christine , Quandt Eckhard , Wagner Bernhard , Schmidt Gerhard , Faupel Franz
Published: May 2016

We present an analytical and experimental study on low-noise piezoelectric thin film resonators that utilize the delta-E effect of a magnetostrictive layer to measure magnetic fields at low frequencies. Calculations from a physical model of the electromechanical resonator enable electrode designs to efficiently operate in the first and second transversal bending modes. As predicted by our calculations, the adapted electrode design improves the sensitivity by a factor of 6 and reduces the dynamic range of the sensor output by 16 dB, which significantly eases the requirements on readout electronics. Magnetic measurements show a bandwidth of 100 Hz at a noise level of about 100 pTHz−0.5.
Design of coated standing nanowire array solar cell performing beyond the planar efficiency limits
Authors: Zeng Yang , Ye Qinghao , Shen Wenzhong
Published: May 2016

The single standing nanowire (SNW) solar cells have been proven to perform beyond the planar efficiency limits in both open-circuit voltage and internal quantum efficiency due to the built-in concentration and the shifting of the absorption front. However, the expandability of these nano-scale units to a macro-scale photovoltaic device remains unsolved. The main difficulty lies in the simultaneous preservation of an effective built-in concentration in each unit cell and a broadband high absorption capability of their array. Here, we have provided a detailed theoretical guideline for realizing a macro-scale solar cell that performs furthest beyond the planar limits. The key lies in a complementary design between the light-trapping of the single SNWs and that of the photonic crystal slab formed by the array. By tuning the hybrid HE modes of the SNWs through the thickness of a coaxial dielectric coating, the optimized coated SNW array can sustain an absorption rate over 97.5% for a period as large as 425 nm, which, together with the inherited carrier extraction advantage, leads to a cell efficiency increment of 30% over the planar limit. This work has demonstrated the viability of a large-size solar cell that performs beyond the planar limits.
Satellite bands of the RbCs molecule in the range of highly excited states
Authors: Rakić Mario , Beuc Robert , Bouloufa-Maafa Nadia , Dulieu Olivier , Vexiau Romain , Pichler Goran , Skenderović Hrvoje
Published: May 2016

We report on the observation of three RbCs satellite bands in the blue and green ranges of the visible spectrum. Absorption measurements are performed using all-sapphire cell filled with a mixture of Rb and Cs. We compare high resolution absorption spectrum of Rb-Cs vapor mixture with pure Rb and Cs vapor spectra from the literature. After detailed analysis, the new satellite bands of RbCs molecule at 418.3 nm, 468.3, and 527.5 nm are identified. The origin of these bands is discussed by direct comparison with difference potentials derived from quantum chemistry calculations of RbCs potential energy curves. These bands originate from the lower Rydberg states of the RbCs molecule. This study thus provides further insight into photoassociation of lower Rydberg molecular states, approximately between Cs(7s) + Rb(5s) and Cs(6s) + Rb(6p) asymptotes, in ultracold gases.
General purpose multiplexing device for cryogenic microwave systems
Authors: Chapman Benjamin J. , Moores Bradley A. , Rosenthal Eric I. , Kerckhoff Joseph , Lehnert K. W.
Published: May 2016

We introduce and experimentally characterize a general purpose device for signal processing in circuit quantum electrodynamics systems. The device is a broadband two-port microwave circuit element with three modes of operation: it can transmit, reflect, or invert incident signals between 4 and 8 GHz. This property makes it a versatile tool for lossless signal processing at cryogenic temperatures. In particular, rapid switching (≤15 ns) between these operation modes enables several multiplexing readout protocols for superconducting qubits. We report the device's performance in a two-channel code domain multiplexing demonstration. The multiplexed data are recovered with fast readout times (up to 400 ns) and infidelities ≤10−2 for probe powers ≥7 fW, in agreement with the expectation for binary signaling with Gaussian noise.
Sub-monolayer growth of Ag on flat and nanorippled SiO2 surfaces
Authors: Bhatnagar Mukul , Ranjan Mukesh , Jolley Kenny , Smith Roger , Mukherjee Subroto
Published: May 2016

In-situ Rutherford Backscattering Spectrometry (RBS) and Molecular Dynamics (MD) simulations have been used to investigate the growth dynamics of silver on a flat and the rippled silica surface. The calculated sticking coefficient of silver over a range of incidence angles shows a similar behaviour to the experimental results for an average surface binding energy of a silver adatom of 0.2 eV. This value was used to parameterise the MD model of the cumulative deposition of silver in order to understand the growth mechanisms. Both the model and the RBS results show marginal difference between the atomic concentration of silver on the flat and the rippled silica surface, for the same growth conditions. For oblique incidence, cluster growth occurs mainly on the leading edge of the rippled structure.