bluuebunny/crossref_metadata_2025 huggingface dataset:
Diffusion of vaporous guests into a seemingly non-porous organic crystal
Authors: Herbert Simon A. , Janiak Agnieszka , Thallapally Praveen K. , Atwood Jerry L. , Barbour Leonard J.
Published: October 2014

The tetragonal apohost phase of p-tert-butyltetramethoxythiacalix[4]arene absorbs hydrochloric acid and iodine.
Crystal growth and magnetic ordering of Na2Ni2TeO6 with honeycomb layers and Na2Cu2TeO6 with Cu spin dimers
Authors: Sankar R. , Panneer Muthuselvam I. , Shu G. J. , Chen W. T. , Karna Sunil K. , Jayavel R. , Chou F. C.
Published: October 2014

We report on the crystal growth and magnetic property studies of layered Na2Ni2TeO6 and Na2Cu2TeO6. The former has a honeycomb layer composed of NiO6 octahedra and the latter is composed of paired CuO4 plaquettes connected through TeO6 octahedra.
Light-harvesting capabilities of low band gap donor–acceptor polymers
Authors: Hedström Svante , Henriksson Patrik , Wang Ergang , Andersson Mats R. , Persson Petter
Published: October 2014

The ability of three new and six existing donor–acceptor polymers to absorb strongly at low photon energies is studied experimentally and theoretically, and is related to their chemical structures.
The positions of inner hydroxide groups and aluminium ions in exfoliated kaolinite as indicators of the external chemical environment
Authors: Táborosi Attila , Kurdi Róbert , Szilágyi Róbert K.
Published: October 2014

New insights: a molecular cluster model was created for exfoliated kaolinite using coordination chemistry principles highlighting the remarkable structural differences relative to crystalline kaolinite.
Chemical imaging of live fibroblasts by SERS effective nanofilm
Authors: Radziuk D. , Schuetz R. , Masic A. , Moehwald H.
Published: October 2014

Label-free Raman imaging of live single NIH3T3 fibroblast produced by SERS effective SiO2@Ag–PAA nanoshells in real time.
Why is sulfuric acid a much stronger acid than ethanol? Determination of the contributions by inductive/field effects and electron-delocalization effects
Authors: Lynch Kevin , Maloney Adam , Sowell Austin , Wang Changwei , Mo Yirong , Karty Joel M.
Published: October 2014

Sulfuric acid's greatly enhanced acid strength over ethanol was investigated computationally. Inductive/field effects were determined to account for about three-fourths of this enhancement, and orbital interactions were determined to account for about one-fourth.
Lignin depolymerisation strategies: towards valuable chemicals and fuels
Authors: Xu Chunping , Arancon Rick Arneil D. , Labidi Jalel , Luque Rafael
Published: October 2014

Research on lignin deconstruction has recently become the center of interest for scientists and companies worldwide, racing towards harvesting fossil-fuel like aromatic compounds which are so durably put together by plants as products of millions of years of evolution.
Active layer solution-processed NIR-OLEDs based on ternary erbium(iii) complexes with 1,1,1-trifluoro-2,4-pentanedione and different N,N-donors
Authors: Martín-Ramos P. , Coya C. , Lavín V. , Martín I. R. , Silva M. Ramos , Silva P. S. Pereira , García-Vélez M. , Álvarez A. L. , Martín-Gil J.
Published: October 2014

The impact of the diimide ancillary ligand choice on the EL properties has been assessed for NIR-OLEDs based on three novel Er(iii) fluorinated β-diketonate complexes.
In situ Nd isotope analyses in geological materials with signal enhancement and non-linear mass dependent fractionation reduction using laser ablation MC-ICP-MS
Authors: Xu Lei , Hu Zhaochu , Zhang Wen , Yang Lu , Liu Yongsheng , Gao Shan , Luo Tao , Hu Shenghong
Published: October 2014

Combining high-efficiency cones with the addition of nitrogen in laser ablation MC-ICP-MS not only enhances the sensitivity and mass bias stability, but also suppresses the non-linear mass fractionation for Nd isotope analyses.
Rapid production of cyclonic spray chambers for inductively coupled plasma applications using low cost 3D printer technology
Authors: Thompson David F.
Published: October 2014

Rapid production of prototype cyclonic spray chambers to enhance research using low-cost additive 3D printing technology.
Multiplexed microfluidic blotting of proteins and nucleic acids by parallel, serpentine microchannels
Authors: He Sha , Zhang Yi , Wang Pei , Xu Xingzhi , Zhu Kui , Pan Wenying , Liu Wenwen , Cai Kaiyong , Sun Jiashu , Zhang Wei , Jiang Xingyu
Published: October 2014

A high-throughput, high-efficiency and straightforward microfluidic blotting method for analyzing proteins and nucleic acids.
Microfluidic platform generates oxygen landscapes for localized hypoxic activation
Authors: Rexius-Hall Megan L. , Mauleon Gerardo , Malik Asrar B. , Rehman Jalees , Eddington David T.
Published: October 2014

An open-well microfluidic platform generates an oxygen landscape using gas-perfused networks which diffuse across a membrane.
A fluorescent light-up nanoparticle probe with aggregation-induced emission characteristics and tumor-acidity responsiveness for targeted imaging and selective suppression of cancer cells
Authors: Ding Dan , Kwok Ryan T. K. , Yuan Youyong , Feng Guangxue , Tang Ben Zhong , Liu Bin
Published: October 2014

The first pH-responsive light-up AIE nanoparticle probe was designed and synthesized for targeted imaging and selective suppression of cancer cells.
High precision and high yield fabrication of dense nanoparticle arrays onto DNA origami at statistically independent binding sites
Authors: Takabayashi Sadao , Klein William P. , Onodera Craig , Rapp Blake , Flores-Estrada Juan , Lindau Elias , Snowball Lejmarc , Sam Joseph T. , Padilla Jennifer E. , Lee Jeunghoon , Knowlton William B. , Graugnard Elton , Yurke Bernard , Kuang Wan , Hughes William L.
Published: October 2014

Nanoparticle arrays self-assembled in the absence of site-bridging, steric hindrance, and electrostatic repulsion.
General design of hollow porous CoFe2O4nanocubes from metal–organic frameworks with extraordinary lithium storage
Authors: Guo Hong , Li Tingting , Chen Weiwei , Liu Lixiang , Yang Xiangjun , Wang Yapeng , Guo Yicheng
Published: October 2014

A facile generic strategy is employed to prepare hollow porous CoFe2O4nanocubesviaMOFs. The hollow nature as well as the multi-elements characteristics of active components of the nanostructure contributes greatly to the outstanding electrochemical performance.
A FeCl2-graphite sandwich composite with Cl doping in graphite layers: a new anode material for high-performance Li-ion batteries
Authors: Wang Lili , Guo Cong , Zhu Yongchun , Zhou Jianbin , Fan Long , Qian Yitai
Published: October 2014

A composite with FeCl2nanocrystals sandwiched between Cl-doped graphite layers was created as a new type of anode material for Li-ion batteries exhibiting high performance.
Unusual (Z)-selective palladium(ii)-catalysed addition of aryl boronic acids to vinylaziridines
Authors: Yin JieXiang , Mekelburg Theresa , Hyland Christopher
Published: October 2014

The palladium(ii)-catalysed addition of arylboronic acids to vinylaziridines has been developed. This reaction proceeds via an insertion/ring-opening process to provide (E)-allylsulfonamides. This stereoselectivity is complimentary to existing methods that typically proceed via an SN2′ mechanism to yield (Z)-allylic systems.
One-pot synthesis of 5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-one derivatives
Authors: Dong Hong-Ru , Gao Zhong-Lian , Li Rong-Shan , Hu Yi-Ming , Dong Heng-Shan , Xie Zhi-Xiang
Published: October 2014

A novel and efficient one-pot method has been developed for the synthesis of 2-substituted-5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-one derivatives by the tandem reaction of [3 + 3] cycloaddition, reduction, deamination.
Exploring highly energetic aliphatic azido nitramines for plasticizers
Authors: Yang Junqing , Zhang Xueli , Gao Pin , Gong Xuedong , Wang Guixiang
Published: October 2014

A set of energetic aliphatic azido nitramines was designed and studied theoretically to find new promising azido nitramine plasticizers for propellants and to investigate the effect of the –CH2NNO2– group on performance.
A cyclic tetranuclear cuboid type copper(ii) complex doubly supported by cyclohexane-1,4-dicarboxylate: molecular and supramolecular structure and cyclohexane oxidation activity
Authors: Hazra Susanta , Mukherjee Sanghamitra , Guedes da Silva M. Fátima C. , Pombeiro Armando J. L.
Published: October 2014

A rare isolated tetranuclear 3d complex with a single metal CDC cuboid cage. It catalyzes cyclohexane peroxidative oxidation without any promoter.
Reinforcing effect on the tribological behaviour of nanoparticles due to a bimodal grain size distribution
Authors: Xu Nan , Li Weimin , Zhang Ming , Zhao Gaiqing , Wang Xiaobo
Published: October 2014

A novel reinforcing mechanism for the tribological performance based on a bimodal grain size distribution is reported.
Probing luminescent Fe-doped ZnO nanowires for high-performance oxygen gas sensing application
Authors: Vyas Rishi , Kumar Pawan , Dwivedi Jaya , Sharma Sarla , Khan Shabana , Divakar R. , Anshul Avneesh , Sachdev K. , Sharma S. K. , Gupta Bipin Kumar
Published: October 2014

Successful demonstration of Fe-doped ZnO nanowires using a facile vapour phase transport synthesis method for high-performance oxygen gas sensing application.
Experimental evaluation of the gas recovery factor of methane hydrate in sandy sediment
Authors: Konno Yoshihiro , Jin Yusuke , Shinjou Kazunori , Nagao Jiro
Published: October 2014

Recovery factor of methane hydrate in sandy sediments can be enhanced using the sensible heat of the hydrate-bearing sediments and the latent heat of ice formation by applying deep depressurization.
Probing 2D sub-bands of bi-layer graphene
Authors: Huang Cheng-Wen , Lin Bing-Jie , Juang Sung-Yen , Shih Fu-Yu , Wang Wei-Hua , Liu Chih-Yi , Chui Hsiang-Chen
Published: October 2014

Investigations of Raman spectra and surface enhanced Raman spectra (SERS) of supported and suspended bilayer graphene were realized.
Simple approach for the immobilization of horseradish peroxidase on poly-l-histidine modified reduced graphene oxide for amperometric determination of dopamine and H2O2
Authors: Vilian A. T. Ezhil , Chen Shen-Ming
Published: October 2014

In this work, immobilization of horseradish peroxidase (HRP) on poly-l-histidine (P-l-His) modified reduced graphene oxide (RGO) was demonstrated.
Novel Pd-decorated amorphous Ni–B/C catalysts with enhanced oxygen reduction reaction activities in alkaline media
Authors: Wang Haining , Cao Di , Xiang Yan , Liang Dawei , Lu Shanfu
Published: October 2014

Pd-decorated amorphous Ni–B/C catalysts were successfully synthesized which exhibited enhanced oxygen reduction reaction activities in alkaline media.
From solid carbon sources to carbon nanotubes: a general water-assisted approach
Authors: Zhang Su , Qin Lei , Song Huaihe , Chen Xiaohong , Zhou Jisheng , Ma Zhaokun
Published: October 2014

We reported a universal approach to prepare carbon nanotubes from solid-state carbons.
The p–n heterojunction with porous BiVO4 framework and well-distributed Co3O4 as a super visible-light-driven photocatalyst
Authors: Dang Xueming , Zhang Xiufang , Dong Xiaoli , Ruan Wenqi , Ma Hongchao , Xue Mang
Published: October 2014

The p–n heterojunction with mesoporous BiVO4 framework well-distributed Co3O4 is fabricated.
Rational design of small indolic squaraine dyes with large two-photon absorption cross section
Authors: Sun Chun-Lin , Liao Qing , Li Ting , Li Jun , Jiang Jian-Qiao , Xu Zhen-Zhen , Wang Xue-Dong , Shen Rong , Bai De-Cheng , Wang Qiang , Zhang Sheng-Xiang , Fu Hong-Bing , Zhang Hao-Li
Published: October 2014

Assisted by theoretical analysis, we designed a small indolic squaraine with δ > 8000 GM at 780 nm, which is ideal for both in vitro and in vivo bio-imaging applications.
One-step synthesis of Co-doped Zn2SnO4–graphene–carbon nanocomposites with improved lithium storage performances
Authors: Wang Hui-Yuan , Wang Bang-Yong , Meng Jin-Kui , Wang Jin-Guo , Jiang Qi-Chuan
Published: October 2014

Co-doped Zn2SnO4–graphene–carbon nanocomposites have been prepared for the first time through a convenient one-step hydrothermal method.
One-pot synthesis of porous nickel cobalt sulphides: tuning the composition for superior pseudocapacitance
Authors: Chen Haichao , Jiang Jianjun , Zhao Yuandong , Zhang Li , Guo Danqing , Xia Dandan
Published: October 2014

Superior pseudocapacitance with high specific capacitance, excellent rate capability and improved cycling stability has been attained by tuning the Ni and Co content of Ni–Co sulphides.
Emitters as probes of a complex plasmo-photonic mode
Authors: Fauché Pierre , Ungureanu Simona , Kolaric Branko , Vallée Renaud A. L.
Published: October 2014

A scheme of the hybrid plasmo-photonic structure manufacturing process – angular transmission spectra and asymmetric emission rate enhancement of the deposited QDs.
Mouse aldehyde dehydrogenase ALDH3B2 is localized to lipid droplets via two C-terminal tryptophan residues and lipid modification
Authors: Kitamura Takuya , Takagi Shuyu , Naganuma Tatsuro , Kihara Akio
Published: October 2014

Aldehyde dehydrogenases (ALDHs) catalyse the conversion of toxic aldehydes into non-toxic carboxylic acids. Of the 21 ALDHs in mice, it is the ALDH3 family members (ALDH3A1, ALDH3A2, ALDH3B1, ALDH3B2 and ALDH3B3) that are responsible for the removal of lipid-derived aldehydes. However, ALDH3B2 and ALDH3B3 have yet to be characterized. In the present study, we examined the enzyme activity, tissue distribution and subcellular localization of ALDH3B2 and ALDH3B3. Both were found to exhibit broad substrate preferences from medium- to long-chain aldehydes, resembling ALDH3A2 and ALDH3B1. Although ALDH3B2 and ALDH3B3 share extremely high sequence similarity, their localizations differ, with ALDH3B2 found in lipid droplets and ALDH3B3 localized to the plasma membrane. Both were modified by prenylation at their C-termini; this modification greatly influenced their membrane localization and enzymatic activity towards hexadecanal. We found that their C-terminal regions, particularly the two tryptophan residues (Trp462 and Trp469) of ALDH3B2 and the two arginine residues (Arg462 and Arg463) of ALDH3B3, were important for the determination of their specific localization. Abnormal quantity and perhaps quality of lipid droplets are implicated in several metabolic diseases. We speculate that ALDH3B2 acts to remove lipid-derived aldehydes in lipid droplets generated via oxidative stress as a quality control mechanism.
Solution structures and dynamics of ADF/cofilins UNC-60A and UNC-60B fromCaenorhabditis elegans
Authors: Shukla Vaibhav Kumar , Kabra Ashish , Maheshwari Diva , Yadav Rahul , Jain Anupam , Tripathi Sarita , Ono Shoichiro , Kumar Dinesh , Arora Ashish
Published: October 2014

The nematode Caenorhabditis elegans has two ADF (actin-depolymerizing factor)/cofilin isoforms, UNC-60A and UNC-60B, which are expressed by the unc60 gene by alternative splicing. UNC-60A has higher activity to cause net depolymerization, and to inhibit polymerization, than UNC-60B. UNC-60B, on the other hand, shows much stronger severing activity than UNC-60A. To understand the structural basis of their functional differences, we have determined the solution structures of UNC-60A and UNC-60B proteins and characterized their backbone dynamics. Both UNC-60A and UNC-60B show a conserved ADF/cofilin fold. The G-actin (globular actin)-binding regions of the two proteins are structurally and dynamically conserved. Accordingly, UNC-60A and UNC-60B individually bind to rabbit muscle ADP–G-actin with high affinities, with Kd values of 32.25 nM and 8.62 nM respectively. The primary differences between these strong and weak severing proteins were observed in the orientation and dynamics of the F-actin (filamentous actin)-binding loop (F-loop). In the strong severing activity isoform UNC-60B, the orientation of the F-loop was towards the recently identified F-loop-binding region on F-actin, and the F-loop was relatively more flexible with 14 residues showing motions on a nanosecond–picosecond timescale. In contrast, in the weak severing protein isoform UNC-60A, the orientation of the F-loop was away from the F-loop-binding region and inclined towards its own C-terminal and strand β6. It was also relatively less flexible with only five residues showing motions on a nanosecond–picosecond timescale. These differences in structure and dynamics seem to directly correlate with the differential F-actin site-binding and severing properties of UNC-60A and UNC-60B, and other related ADF/cofilin proteins.
NMR structure of the water soluble Aβ17–34 peptide
Authors: Fonar Genadiy , Samson Abraham O.
Published: October 2014

Alzheimer's disease is the most common neurodegenerative disorder in the world. Its most significant symptoms are memory loss and decrease in cognition. Alzheimer's disease is characterized by aggregation of two proteins in the brain namely Aβ (amyloid β) and tau. Recent evidence suggests that the interaction of soluble Aβ with nAChR (nicotinic acetylcholine receptors) contributes to disease progression. In this study, we determine the NMR structure of an Aβ17–34 peptide solubilized by the addition of two glutamic acids at each terminus. Our results indicate that the Aβ peptide adopts an α-helical structure for residues 19–26 and 28–33. The α-helical structure is broken around residues S26, N27 and K28, which form a kink in the helical conformation. This α-helix was not described earlier in an aqueous solution without organic solvents, and at physiological conditions (pH 7). These data are in agreement with Aβ adopting an α-helical conformation in the membrane before polymerizing into amyloid β-sheets and provide insight into the intermediate state of Aβ in Alzheimer's disease.
Dissipativity‐based integral sliding‐mode control for a class of Takagi–Sugeno fuzzy singular systems with time‐varying delay
Authors: Kchaou Mourad , Gassara Hamdi , El‐Hajjaji Ahmed , Toumi Ahmed
Published: October 2014

The problem of sliding‐mode control (SMC) with dissipativity for a class of time‐delay Takagi–Sugeno fuzzy singular systems is investigated. The system is subject to uncertainties and input non‐linearity. Based on an integral sliding surface, a delay‐dependent criterion is developed in terms of linear matrix inequalities, which ensures the sliding mode dynamics to be robustly admissible and strictly (𝓆𝒮ℛ)‐dissipative. Moreover, an SMC law is established such that the reachability of the specified sliding surface is guaranteed. Finally, the validity and applicability of the proposed approach are illuminated by two simulation examples.
Non‐enzymatic electrochemical sensors for the detection of H2O2 based on Mn3O4 octahedron submicrostructures
Authors: Wang Liang , Wu Kong‐Lin , Jiang Bin‐Bin , Zhang Zai‐Xian , Li Xiang‐Zi , Zhang Bei , Lv Ju , Suan Jian , Dong Chao
Published: October 2014

In this reported work, Mn3O4 octahedron submicrostructures (Mn3O4OSMs) were obtained through a facile solvothermal method in mixed solvent. The authors have modified a glassy carbon electrode (GCE) with Mn3O4OSMs and Nafion to obtain a sensing platform (Mn3O4OSMs/Nafion/GCE) for the non‐enzymatic detection of H2O2. The resulting Mn3O4OSMs/Nafion/GCE exhibited good electrochemical catalytic activity towards the reduction of H2O2 in a phosphate buffered solution (0.1 M, pH = 7.0). The linear detection range was estimated to be in the range from 5 µM to 17 mM (R = 0.9998), and the detection limit was estimated to be 1.5 µM at S/N = 3. Real sample analyses show that the sensor developed in this work could be efficiently used for the determination of H2O2.
Selective patterning of indium tin oxide films using 1064 nm laser for microparts processing
Authors: Chung Chen‐Kuei , Tu Kun‐Tse
Published: October 2014

Conventional metal microparts were fabricated by a series of complex photolithography, sputtering, sacrificial layer and release processes. This reported work demonstrates the integrated process of metal microparts using 1064 nm Nd:YVO4 laser direct‐write patterning of indium tin oxide (ITO) thin films on glass, followed by the electrochemical deposition of copper (Cu) on the pattern. The ITO thin film could be removed without any damage to the glass structure through the diffractive multiple Nd:YVO4 beam. A high overlapping area of the laser spot was used to pattern the electrode layer on the film surface for obtaining a 50 µm ablated edge profile with a linear boundary after laser patterning. A high quality of surface could be achieved at a proper parameter control without numerous processing steps. Compared with conventional photolithography and etching technologies, direct‐write micropatterns of ITO using the Nd:YVO4 laser is a maskless, dry and low‐cost process. Accordingly, the micrometal parts can be obtained using the electrochemical deposition and release process of laser‐patterned ITO films because of the adhesion property of Cu on ITO.
Is Theory King?: A Rejoinder
Authors: Avison David , Malaurent Julien
Published: October 2014

In this rejoinder we discuss six commentaries to our earlier debates and perspectives paper ‘Is theory king?: questioning the theory fetish in information systems’. We argue again for theory light rather than theory free papers, we discuss the potential scope of theories in information systems, we reflect on our terminology and exemplar paper, and we discuss the relevance of our arguments on quantitative research before looking at potential further opportunities to debate this important issue for information systems.
Clusters, molecular layers, and 3D crystals of water on Ni(111)
Authors: Thürmer Konrad , Nie Shu , Feibelman Peter J. , Bartelt Norman C.
Published: October 2014

We examined the growth and stability of ice layers on Ni(111) up to ∼7 molecular layers (ML) thick using scanning tunneling microscopy. At low coverage, films were comprised of ∼1 nm wide two-dimensional (2D) clusters. Only above ∼0.5 ML did patches of continuous 2D layers emerge, coexisting with the clusters until the first ML was complete. The structure of the continuous layer is clearly different from that of the 2D clusters. Subsequently, a second molecular layer grew on top of the first. 3D crystallites started to form only after this 2nd ML was complete. 2D clusters re-appeared when thicker films were partially evaporated, implying that these clusters represent the equilibrium configuration at low coverage. Binding energies and image simulations computed with density functional theory suggest that the 2D clusters are partially dissociated and surrounded by H adatoms. The complete 2D layer contains only intact water molecules because of the lack of favorable binding sites for H atoms. We propose molecular structures for the 2D layer that are composed of the same pentagon-heptagon binding motif and water density observed on Pt(111). The similarity of the water structures on Pt and Ni suggests a general prescription for generating low-energy configurations on close-packed metal substrates.
Effective interaction between a colloid and a soft interface near criticality
Authors: Law A. D. , Harnau L. , Tröndle M. , Dietrich S.
Published: October 2014

Within mean-field theory we determine the universal scaling function for the effective force acting on a single colloid located near the interface between two coexisting liquid phases of a binary liquid mixture close to its critical consolute point. This is the first study of critical Casimir forces emerging from the confinement of a fluctuating medium by at least one shape responsive, soft interface, instead of by rigid walls only as studied previously. For this specific system, our semi-analytical calculation illustrates that knowledge of the colloid-induced, deformed shape of the interface allows one to accurately describe the effective interaction potential between the colloid and the interface. Moreover, our analysis demonstrates that the critical Casimir force involving a deformable interface is accurately described by a universal scaling function, the shape of which differs from that one for rigid walls.
Mechanical unfolding of a simple model protein goes beyond the reach of one-dimensional descriptions
Authors: Tapia-Rojo R. , Arregui S. , Mazo J. J. , Falo F.
Published: October 2014

We study the mechanical unfolding of a simple model protein. The Langevin dynamics results are analyzed using Markov-model methods which allow to describe completely the configurational space of the system. Using transition-path theory we also provide a quantitative description of the unfolding pathways followed by the system. Our study shows a complex dynamical scenario. In particular, we see that the usual one-dimensional picture: free-energy vs end-to-end distance representation, gives a misleading description of the process. Unfolding can occur following different pathways and configurations which seem to play a central role in one-dimensional pictures are not the intermediate states of the unfolding dynamics.
Coherent state transforms and the Mackey-Stone-Von Neumann theorem
Authors: Kirwin William D. , Mourão José M. , Nunes João P.
Published: October 2014

Mackey showed that for a compact Lie group K, the pair (K, C 0(K)) has a unique non-trivial irreducible covariant pair of representations. We study the relevance of this result to the unitary equivalence of quantizations for an infinite-dimensional family of K × K invariant polarizations on T*K. The Kähler polarizations in the family are generated by (complex) time-τ Hamiltonian flows applied to the (Schrödinger) vertical real polarization. The unitary equivalence of the corresponding quantizations of T*K is then studied by considering covariant pairs of representations of K defined by geometric prequantization and of representations of C 0(K) defined via Heisenberg time-(−τ) evolution followed by time-(+τ) geometric-quantization-induced evolution. We show that in the semiclassical and large imaginary time limits, the unitary transform whose existence is guaranteed by Mackey's theorem can be approximated by composition of the time-(+τ) geometric-quantization-induced evolution with the time-(−τ) evolution associated with the momentum space [W. D. Kirwin and S. Wu, “Momentum space for compact Lie groups and the Peter-Weyl theorem” (unpublished)] quantization of the Hamiltonian function generating the flow. In the case of quadratic Hamiltonians, this asymptotic result is exact and unitary equivalence between quantizations is achieved by identifying the Heisenberg imaginary time evolution with heat operator evolution, in accordance with the coherent state transform of Hall.
Quantization of a particle on a two-dimensional manifold of constant curvature
Authors: Bracken Paul
Published: October 2014

The formulation of quantum mechanics on spaces of constant curvature is studied. It is shown how a transition from a classical system to the quantum case can be accomplished by the quantization of the Noether momenta. These can be determined by means of Lie differentiation of the metric which defines the manifold. For the metric examined here, it is found that the resulting Schrödinger equation is separable and the spectrum and eigenfunctions can be investigated in detail.
Long-lived polarization protected by symmetry
Authors: Feng Yesu , Theis Thomas , Wu Tung-Lin , Claytor Kevin , Warren Warren S.
Published: October 2014

In this paper we elucidate, theoretically and experimentally, molecular motifs which permit Long-Lived Polarization Protected by Symmetry (LOLIPOPS). The basic assembly principle starts from a pair of chemically equivalent nuclei supporting a long-lived singlet state and is completed by coupling to additional pairs of spins. LOLIPOPS can be created in various sizes; here we review four-spin systems, introduce a group theory analysis of six-spin systems, and explore eight-spin systems by simulation. The focus is on AA′XnX′n spin systems, where typically the A spins are 15N or 13C and X spins are protons. We describe the symmetry of the accessed states, we detail the pulse sequences used to access these states, we quantify the fraction of polarization that can be stored as LOLIPOPS, we elucidate how to access the protected states from A or from X polarization and we examine the behavior of these spin systems upon introduction of a small chemical shift difference.
Printable sensors for explosive detonation
Authors: Griffith Matthew J. , Cooling Nathan A. , Elkington Daniel C. , Muller Elmar , Belcher Warwick J. , Dastoor Paul C.
Published: October 2014

Here, we report the development of an organic thin film transistor (OTFT) based on printable solution processed polymers and employing a quantum tunnelling composite material as a sensor to convert the pressure wave output from detonation transmission tubing (shock tube) into an inherently amplified electronic signal for explosives initiation. The organic electronic detector allows detection of the signal in a low voltage operating range, an essential feature for sites employing live ordinances that is not provided by conventional electronic devices. We show that a 30-fold change in detector response is possible using the presented detector assembly. Degradation of the OTFT response with both time and repeated voltage scans was characterised, and device lifetime is shown to be consistent with the requirements for on-site printing and usage. The integration of a low cost organic electronic detector with inexpensive shock tube transmission fuse presents attractive avenues for the development of cheap and simple assemblies for precisely timed initiation of explosive chains.
Conformational transitions of a weak polyampholyte
Authors: Narayanan Nair Arun Kumar , Uyaver Sahin , Sun Shuyu
Published: October 2014

Using grand canonical Monte Carlo simulations of a flexible polyelectrolyte where the charges are in contact with a reservoir of constant chemical potential given by the solution pH, we study the behavior of weak polyelectrolytes in poor and good solvent conditions for polymer backbone. We address the titration behavior and conformational properties of a flexible diblock polyampholyte chain formed of two oppositely charged weak polyelectrolyte blocks, each containing equal number of identical monomers. The change of solution pH induces charge asymmetry in a diblock polyampholyte. For diblock polyampholyte chains in poor solvents, we demonstrate that a discontinuous transition between extended (tadpole) and collapsed (globular) conformational states is attainable by varying the solution pH. The double-minima structure in the probability distribution of the free energy provides direct evidence for the first-order like nature of this transition. At the isoelectric point electrostatically driven coil-globule transition of diblock polyampholytes in good solvents is found to consist of different regimes identified with increasing electrostatic interaction strength. At pH values above or below the isoelectric point diblock chains are found to have polyelectrolyte-like behavior due to repulsion between uncompensated charges along the chain.
Hyperparametric effects in a whispering-gallery mode rutile dielectric resonator at liquid helium temperatures
Authors: Nand Nitin R. , Goryachev Maxim , Floch Jean-Michel le , Creedon Daniel L. , Tobar Michael E.
Published: October 2014

We report the first observation of low power drive level sensitivity, hyperparametric amplification, and single-mode hyperparametric oscillations in a dielectric rutile whispering-gallery mode resonator at 4.2 K. The latter gives rise to a comb of sidebands at 19.756 GHz. Whereas, most frequency combs in the literature have been observed in optical systems using an ensemble of equally spaced modes in microresonators or fibers, the present work represents generation of a frequency comb using only a single-mode. The experimental observations are explained by an additional 1/2 degree-of-freedom originating from an intrinsic material nonlinearity at optical frequencies, which affects the microwave properties due to the extremely low loss of rutile. Using a model based on lumped circuits, we demonstrate that the resonance between the photonic and material 1/2 degree-of-freedom, is responsible for the hyperparametric energy transfer in the system.
Simulation of magnetic island dynamics under resonant magnetic perturbation with the TEAR code and validation of the results on T-10 tokamak data
Authors: Ivanov N. V. , Kakurin A. M.
Published: October 2014

Simulation of the magnetic island evolution under Resonant Magnetic Perturbation (RMP) in rotating T-10 tokamak plasma is presented with intent of TEAR code experimental validation. In the T-10 experiment chosen for simulation, the RMP consists of a stationary error field, a magnetic field of the eddy current in the resistive vacuum vessel and magnetic field of the externally applied controlled halo current in the plasma scrape-off layer (SOL). The halo-current loop consists of a rail limiter, plasma SOL, vacuum vessel, and external part of the circuit. Effects of plasma resistivity, viscosity, and RMP are taken into account in the TEAR code based on the two-fluid MHD approximation. Radial distribution of the magnetic flux perturbation is calculated with account of the externally applied RMP. A good agreement is obtained between the simulation results and experimental data for the cases of preprogrammed and feedback-controlled halo current in the plasma SOL.
The overall elastic dielectric properties of a suspension of spherical particles in rubber: An exact explicit solution in the small-deformation limit
Authors: Lefèvre Victor , Lopez-Pamies Oscar
Published: October 2014

A solution is constructed for the homogenization problem of the elastic dielectric response of rubber filled with a random isotropic distribution of polydisperse spherical particles in the classical limit of small deformations and moderate electric fields. In this limit, the overall elastic dielectric response is characterized by five (two elastic, one dielectric, and two electrostrictive) effective constants. Explicit formulas are derived for these constants directly in terms of the corresponding constants describing the elastic dielectric response of the underlying rubber and the filler particles, as well as the concentration of particles. By means of comparisons with finite-element simulations, these formulas are shown to also be applicable to isotropic suspensions of monodisperse spherical particles, provided that the particle concentration is sufficiently away from percolation. With the aim of gaining physical insight into the extreme enhancement in electrostrictive properties displayed by emerging dielectric elastomer composites, specific results are examined for the case of suspensions wherein the rubber is incompressible and the particles are mechanically rigid and of infinite permittivity.
Communication: A density functional investigation of structure-property evolution in the tetrakis hexahedral C4Al14 nanocluster
Authors: Irving Benjamin J. , Naumkin Fedor Y.
Published: October 2014

Nanoclusters are prime objects of study in modern nanotechnology and offer a variety of applications promoted by their properties tunable by size, shape, and composition. DFT calculations are employed to analyze structure, stability, and selected electronic properties of a core-shell C4Al14 species. With insertion of the carbon core, the original low-symmetry aluminum cluster is predicted to undergo a considerable reshaping and acquire a striking D4h tetrakis-hexahedral geometry, with proportions controlled by a near-degenerate spin state or charge. The system also becomes more stable to dissociation. Surprisingly, other properties such as ionisation energy and electron affinity do not change significantly, although still exhibit some interesting features including opposite variations for vertical and adiabatic values. The stability and property evolutions are analyzed in terms of contributions from reshaping of the shell and its further interaction with the core. The system thus has potential applications as a symmetric building unit and a molecular device for nano-electronics/spintronics.
Hydrodynamic resistance and mobility of deformable objects in microfluidic channels
Authors: Sajeesh P. , Doble M. , Sen A. K.
Published: October 2014

This work reports experimental and theoretical studies of hydrodynamic behaviour of deformable objects such as droplets and cells in a microchannel. Effects of mechanical properties including size and viscosity of these objects on their deformability, mobility, and induced hydrodynamic resistance are investigated. The experimental results revealed that the deformability of droplets, which is quantified in terms of deformability index (D.I.), depends on the droplet-to-channel size ratio ρ and droplet-to-medium viscosity ratio λ. Using a large set of experimental data, for the first time, we provide a mathematical formula that correlates induced hydrodynamic resistance of a single droplet ΔRd with the droplet size ρ and viscosity λ. A simple theoretical model is developed to obtain closed form expressions for droplet mobility ϕ and ΔRd. The predictions of the theoretical model successfully confront the experimental results in terms of the droplet mobility ϕ and induced hydrodynamic resistance ΔRd. Numerical simulations are carried out using volume-of-fluid model to predict droplet generation and deformation of droplets of different size ratio ρ and viscosity ratio λ, which compare well with that obtained from the experiments. In a novel effort, we performed experiments to measure the bulk induced hydrodynamic resistance ΔR of different biological cells (yeast, L6, and HEK 293). The results reveal that the bulk induced hydrodynamic resistance ΔR is related to the cell concentration and apparent viscosity of the cells.
InGaN/GaN tunnel junctions for hole injection in GaN light emitting diodes
Authors: Krishnamoorthy Sriram , Akyol Fatih , Rajan Siddharth
Published: October 2014

InGaN/GaN tunnel junction contacts were grown using plasma assisted molecular beam epitaxy (MBE) on top of a metal-organic chemical vapor deposition (MOCVD)-grown InGaN/GaN blue (450 nm) light emitting diode. A voltage drop of 5.3 V at 100 mA, forward resistance of 2 × 10−2 Ω cm2, and a higher light output power compared to the reference light emitting diodes (LED) with semi-transparent p-contacts were measured in the tunnel junction LED (TJLED). A forward resistance of 5 × 10−4 Ω cm2 was measured in a GaN PN junction with the identical tunnel junction contact as the TJLED, grown completely by MBE. The depletion region due to the impurities at the regrowth interface between the MBE tunnel junction and the MOCVD-grown LED was hence found to limit the forward resistance measured in the TJLED.
Homogeneous and inhomogeneous sources of optical transition broadening in room temperature CdSe/ZnS nanocrystal quantum dots
Authors: Wolf M. , Berezovsky J.
Published: October 2014

We perform photoluminescence excitation measurements on individual CdSe/ZnS nanocrystal quantum dots (NCQDs) at room temperature to study optical transition energies and broadening. The observed features in the spectra are identified and compared to calculated transition energies using an effective mass model. The observed broadening is attributed to phonon broadening, spectral diffusion, and size and shape inhomogeneity. The former two contribute to the broadening transitions in individual QDs, while the latter contributes to the QD-to-QD variation. We find that phonon broadening is often not the dominant contribution to transition line widths, even at room temperature, and that broadening does not necessarily increase with transition energy. This may be explained by differing magnitude of spectral diffusion for different quantum-confined states.
Hybridizing matter-wave and classical accelerometers
Authors: Lautier J. , Volodimer L. , Hardin T. , Merlet S. , Lours M. , Pereira Dos Santos F. , Landragin A.
Published: October 2014

We demonstrate a hybrid accelerometer that benefits from the advantages of both conventional and atomic sensors in terms of bandwidth (DC to 430 Hz) and long term stability. First, the use of a real time correction of the atom interferometer phase by the signal from the classical accelerometer enables to run it at best performance without any isolation platform. Second, a servo-lock of the DC component of the conventional sensor output signal by the atomic one realizes a hybrid sensor. This method paves the way for applications in geophysics and in inertial navigation as it overcomes the main limitation of atomic accelerometers, namely, the dead times between consecutive measurements.
Intensive Mobilities: Figurations of the Nomad in Contemporary Theory
Authors: Sutherland Thomas
Published: October 2014

The figure of the nomad, representing the virtues of freedom, mobility, and exploration, is a frequently occurring trope within contemporary continental philosophy and social theory, derived chiefly from the work of Gilles Deleuze and Félix Guattari. This paper will interrogate the concept of nomadism, firstly in the philosophy of these two foundational thinkers, and then subsequently in the feminist and posthumanist theorizations of Rosi Braidotti. Whilst accepting that Braidotti's challenges to sedentarist, essentialist metaphysical accounts of the transcendental subject are still politically relevant, it will be argued that the deployment of the nomadic figure—and more generally, the positing of an ontology of creative desire, or ‘becoming’—risks not only absolutizing the historical contingencies of the digitized, postindustrial society that it seeks to criticize, but actually reinforcing the unsustainable ideology of perpetual production upon which such a society is premised.
Pasture cropping with C4 grasses in a barley–lupin rotation can increase production
Authors: Lawes R. A. , Ward P. R. , Ferris D.
Published: October 2014

In southern Australia, intercropping, pasture cropping and overcropping have evolved as techniques to address environmental problems such as dryland salinity and wind erosion and to utilise soil water outside the conventional winter-dominant growing season. We paired three winter-dormant pastures, including two subtropical C4 perennial species (Rhodes grass, Chloris gayana; Gatton panic, Megathyrsus maximus) and the summer-active perennial C3 legume siratro (Macroptilium atropurpureum), with a conventional barley (Hordeum vulgare)–lupin (Lupinus angustifolius) rotation to explore the extent to which different summer-active species reduced crop yields. We also examined whether the competition for resources could be altered by supplying increased nitrogen to the crop and changing the row spacing of the pasture.
Under high-input conditions, pasture reduced cereal crop yields by up to 26% and lupin yields by up to 29%. Under low-input conditions, pasture cropping did not significantly reduce crop yield, and frequently increased crop yields. With low inputs, barley yield increases in 2011 ranged from 23% to 31%. In lupins under low-input conditions, yield increases ranged from 91% to 106% in 2010 and from –6% to +39% in 2012. The impact of the crop on the pasture was less pronounced, where the timing of pasture growth was delayed by the crop, but absolute levels of production were not influenced by the crop. Row spacing altered the temporal dynamic of pasture production; initially, the pasture produced less than the narrow spaced equivalent, but after 2 years, production exceeded that in the narrow row. Across all pasture species in 2009 and 2012, winter pasture production reduced crop yield by 0.32 and 0.4 t grain/ha pasture biomass produced, implying that moderate yield losses occurred because pasture production was also moderate. In the other two years, winter pasture production did not affect crop yield, suggesting that the pasture was able to utilise resources surplus to crop requirements. In this environment, with this combination of crops and summer-active pastures, higher levels of inputs did not enhance crop yield in a pasture-cropping system. We suggest that grain yield losses are lower in the low-input system and this implies that, at some level, competition between the species was reduced in a nitrogen-limited environment and the extent of the competition depended on season.
Summer-growing perennial grasses are a potential new feed source in the low rainfall environment of southern Australia
Authors: Descheemaeker Katrien , Llewellyn Rick , Moore Andrew , Whitbread Anthony
Published: October 2014

In the Mallee region of southern Australia, the dry and variable climate results in frequent summer–autumn feed gaps, restricting the profitability of farms that combine livestock and crop enterprises. To assess the suitability of summer-growing perennial grasses to fill such feed gaps, two replicated field experiments comparing the persistence and productivity of several cultivars were conducted at Hopetoun and Karoonda. The data from these experiments also served to validate a C4 grass model, which was then used in a simulation experiment comparing productivity on two different soil types at three locations. Most grass cultivars established well except on sandy, non-wetting soils. At Hopetoun, four of five cultivars persisted over 6 years, demonstrating the tolerance of the selected cultivars to the typical long, dry summers and cold, wet winters of the region. Biomass production showed little difference between cultivars and a strong response to the amount of summer rainfall, ranging from 1500 to 3000 kg ha–1 under average seasonal conditions and peaking at 9000 kg ha–1 in the very wet summer of 2010–2011. Model performance was satisfactory (R2 0.85–0.93, RMSE 476–1673 kg ha–1, depending on the cultivar), in terms of predicting both the magnitude and the timing of biomass production. Simulation outputs indicated that biomass production closely followed seasonal trends in temperature and moisture availability. Grazing potential was highest from early summer to autumn, which coincides with the period of feed shortages and highest marginal value of forage. In areas with warm-season (October–April) rainfall averages of 175 and 225 mm, the grazing of C4 grass pastures on marginal soils would be possible in at least 40% of the years for 2 and 3 months, respectively. It was concluded that summer-growing perennials are a promising option to alleviate feed gaps on mixed crop–livestock farms in areas with at least 150 mm of rainfall from October to April.
Perennial pastures in cropping systems of southern Australia: an overview of present and future research
Authors: Robertson Michael , Revell Clinton
Published: October 2014

Addressing the opportunities and challenges for integrating perennial forages and shrubs into the mixed crop–livestock farming systems of southern Australia has been the focus of the Future Farm Industries Cooperative Research Centre EverCrop project. This overview discusses the use of perennial plants in cropping landscapes in terms of the concepts of ‘rotation, separation and integration’ and highlights the contribution of papers in this special issue of Crop and Pasture Science across a range of biophysical and socioeconomic factors. Drivers for the inclusion of perennial forage plants include salinity management, groundcover maintenance and filling seasonal feed gaps, and this need will continue as mixed crop–livestock systems evolve in the context of managing business risk and a requirement for better natural resource management outcomes.