Sample records for basin superstructure laden

  1. Life After Bin Laden

    Institute of Scientific and Technical Information of China (English)


    The Al Qaeda leader’s death is neither the death of his organization nor terrorismThe Al Qaeda leader’s death is neither the death of his organization nor terrorism Almost 10 years after the September 11 terrorist attacks, the United States finally killed Osama Bin Laden, who was

  2. Topological Insulators from Electronic Superstructures (United States)

    Sugita, Yusuke; Motome, Yukitoshi


    The possibility of realizing topological insulators by the spontaneous formation of electronic superstructures is theoretically investigated in a minimal two-orbital model including both the spin-orbit coupling and electron correlations on a triangular lattice. Using the mean-field approximation, we show that the model exhibits several different types of charge-ordered insulators, where the charge disproportionation forms a honeycomb or kagome superstructure. We find that the charge-ordered insulators in the presence of strong spin-orbit coupling can be topological insulators showing quantized spin Hall conductivity. Their band gap is dependent on electron correlations as well as the spin-orbit coupling, and even vanishes while showing the massless Dirac dispersion at the transition to a trivial charge-ordered insulator. Our results suggest a new route to realize and control topological states of quantum matter by the interplay between the spin-orbit coupling and electron correlations.

  3. Implementing Composite Superstructures in Large Passenger Ships

    DEFF Research Database (Denmark)

    Karatzas, Vasileios; Berggreen, Christian; Jensen, Jørgen Juncher;


    This study focuses on the structural response of the part of the superstructure of a RoPax ferry that has been redesigned using composite materials. The composite superstructure is presented and subsequently compared to the existing steel design considering different loading conditions by the use...... of FE modelling.Results indicate that it is not the structural response of the superstructure that inhibits the implementation of composites in the superstructures of large passenger ships but the complicated design procedure and the acceptance of such solutions by the regulatory bodies....

  4. Is Observation Mathematically-Laden?

    Directory of Open Access Journals (Sweden)

    Thomas Michael Muller


    Full Text Available In this article, we will defend the epistemological claim that observation is mathematically- laden. A well-known thesis in the philosophy of science is that observation is theory-laden. The claim that observation is mathematically laden can be similarly justified. The first part of the paper focuses on the definition of mathematically-ladeness and its relations to the best-known problem of theory-ladeness. The second part of the paper presents some explicit examples and outlines the consequences and the difficulties of this epistemological limit. Finally, a specific context for this problem is discussed in detail: we will analyze the question of deterministic chaos as a paradigmatic example of mathematically-ladeness and show that the deterministic or indeterministic nature of chaos is strongly linked to the choice of a particular mathematical description.

  5. Superstructures: First Cold Test and Future Applications

    Energy Technology Data Exchange (ETDEWEB)

    J. Sekutowicz; C Albrecht; V Ayvazyan; R Bandelmann; T Buttner; P Castro; S Choroba; J Eschke; B Faatz; A Gossel; K Honkavaara; B Horst; J Iverson; K Jensch; H Kaiser; R Kammering; G Kreps; D Kostin; J Lorkiewicz; R Lange; A Matheisen; W -D Moller; H -B Peters; D Proch; K Rehlich; H Schlarb; S Schrieber; D Reschke; S Simrock; W Singer; X Singer; K Twarowski; T Weichert; M Wojtkiewicz; G Wendt; K Zapfe; M Liepe; M Huening; M Ferrario; E Plawski; C Pagani; P Kneisel; G Wu; N Baboi; C Thomas; H Chen; W Huang; C Tang; S Zheng


    Superstructures, chains of superconducting multi-cell cavities (subunits) connected by e/2 long tube(s) have been proposed as an alternative layout for the TESLA main accelerator [1]. After three years of preparation, two superstructures, each made of two weakly coupled superconducting 7-cell subunits driven by a single Fundamental Power Coupler (FPC), have been installed in the Tesla Test Facility linac for beam tests. Energy stability, HOM damping, frequency and field adjustment methods were tested. The measured results confirmeSuperstructures, chains of superconducting multi-cell cavities (subunits) connected by e/2 long tube(s) have been proposed as an alternative layout for the TESLA main accelerator [1]. After three years of preparation, two superstructures, each made of two weakly coupled superconducting 7-cell subunits driven by a single Fundamental Power Coupler (FPC), have been installed in the Tesla Test Facility linac for beam tests. Energy stability, HOM damping, frequency and field adjustment methods were tested. The measured results confirmed expectation on the superstructure performance and proved that an alternative layout for the 800 GeV upgrade of the TESLA collider is feasible. We report on the test and give here an overview of its results. The tests confirmed very good damping of HOMs in superstructures and thus has opened a possible new application of this concept to high current energy recovery machines. We have built two 1.5 GHz copper models of two superstructures: 2x5-cells and 2x2-cells to prove further improvement of HOM damping. This contribution presents also measured results on these models. d expectations on the superstructure performance and proved that an alternative layout for the 800 GeV upgrade of the TESLA collider is feasible. We report on the test and give here an overview of its results.

  6. Tetrahedral Units: For Dodecahedral Super-Structures

    CERN Document Server

    Ortiz, Y; Liebman, J F


    Different novel organic-chemical possibilities for tetrahedral building units are considered, with attention to their utility in constructing different super-structures. As a representative construction we consider the use of sets of 20 such identical tetrahedral units to form a super-dodecahedron.

  7. Modular assembly of superstructures from polyphenol-functionalized building blocks (United States)

    Guo, Junling; Tardy, Blaise L.; Christofferson, Andrew J.; Dai, Yunlu; Richardson, Joseph J.; Zhu, Wei; Hu, Ming; Ju, Yi; Cui, Jiwei; Dagastine, Raymond R.; Yarovsky, Irene; Caruso, Frank


    The organized assembly of particles into superstructures is typically governed by specific molecular interactions or external directing factors associated with the particle building blocks, both of which are particle-dependent. These superstructures are of interest to a variety of fields because of their distinct mechanical, electronic, magnetic and optical properties. Here, we establish a facile route to a diverse range of superstructures based on the polyphenol surface-functionalization of micro- and nanoparticles, nanowires, nanosheets, nanocubes and even cells. This strategy can be used to access a large number of modularly assembled superstructures, including core-satellite, hollow and hierarchically organized supraparticles. Colloidal-probe atomic force microscopy and molecular dynamics simulations provide detailed insights into the role of surface functionalization and how this facilitates superstructure construction. Our work provides a platform for the rapid generation of superstructured assemblies across a wide range of length scales, from nanometres to centimetres.

  8. Hydrothermal synthesis and photoluminescent properties of stacked indium sulfide superstructures. (United States)

    Xing, Yan; Zhang, Hongjie; Song, Shuyan; Feng, Jing; Lei, Yongqian; Zhao, Lijun; Li, Meiye


    Unusual hierarchical stacked superstructures of cubic beta-In2S3 were fabricated via a facile hydrothermal process in the presence of a surfactant cetyltrimethylammonium bromide CTAB; the 3D superstructures were developed by helical propagation of surface steps from microflakes of 10-20 nm thickness.

  9. Non covalent assembly of coordination superstructures

    CERN Document Server

    Khlobystov, A N


    The main topic of this work is the design of discrete and polymeric multi-component coordination structures using non-covalent interactions between organic and inorganic molecular components. All of the structures described herein are based on transition metal cations and N-donor heterocyclic bis-exodentate ligands with different geometries and various spacer functionalities. The predominant method used for the structural characterisation of the complexes was single crystal X-ray crystallography. X-ray powder diffraction, IR and NMR spectroscopies and TEM and AFM imaging were used to characterise the bulk products from the reactions. Chapter 1 is a comparative review of non-covalent interactions relevant to coordination superstructures and covers the latest developments in the area of crystal engineering and supramolecular chemistry. The nature, geometry and relative energy of the non-covalent interactions are considered in detail in order to reveal their influence on the structure and properties of complexes...

  10. Enhanced thermophysical properties via PAO superstructure (United States)

    Pournorouz, Zahra; Mostafavi, Amirhossein; Pinto, Aditya; Bokka, Apparao; Jeon, Junha; Shin, Donghyun


    For the last few years, molten salt nanomaterials have attracted many scientists for their enhanced specific heat by doping a minute concentration of nanoparticles (up to 1% by weight). Likewise, enhancing the specific heat of liquid media is important in many aspects of engineering such as engine oil, coolant, and lubricant. However, such enhancement in specific heat was only observed for molten salts, yet other engineering fluids such as water, ethylene glycol, and oil have shown a decrease of specific heat with doped nanoparticles. Recent studies have shown that the observed specific heat enhancement resulted from unique nanostructures that were formed by molten salt molecules when interacting with nanoparticles. Thus, such enhancement in specific heat is only possible for molten salts because other fluids may not naturally form such nanostructures. In this study, we hypothesized such nanostructures can be mimicked through in situ formation of fabricated nano-additives, which are putative nanoparticles coated with useful organic materials (e.g., polar-group-ended organic molecules) leading to superstructures, and thus can be directly used for other engineering fluids. We first applied this approach to polyalphaolefin (PAO). A differential scanning calorimeter (DSC), a rheometer, and a customized setup were employed to characterize the heat capacity, viscosity, and thermal conductivity of PAO and PAO with fabricated nano-additives. Results showed 44.5% enhanced heat capacity and 19.8 and 22.98% enhancement for thermal conductivity and viscosity, respectively, by an addition of only 2% of fabricated nanostructures in comparison with pure PAO. Moreover, a partial melting of the polar-group-ended organic molecules was observed in the first thermal cycle and the peak disappeared in the following cycles. This indicates that the in situ formation of fabricated nano-additives spontaneously occurs in the thermal cycle to form nanostructures. Figure of merit analyses have


    Directory of Open Access Journals (Sweden)

    Tanya Dabeva


    Full Text Available The purpose of the paper is to suggest some terms of reference for the elaboration of the superstructure of the Bulgarian hotel industry. The suggestions are based on the analysis of the superstructure at present. Its capacity, main types of accommodation establishments and their distribution by categories and territory are examined. An analysis is made of some resulting indices such as overnight stays and average stay. The main positive, respectively negative features of the superstructure have been analyzed. Concrete terms of reference have been given in order to overcome the problems specified.

  12. A Generic Methodology for Superstructure Optimization of Different Processing Networks

    DEFF Research Database (Denmark)

    Bertran, Maria-Ona; Frauzem, Rebecca; Zhang, Lei;


    In this paper, we propose a generic computer-aided methodology for synthesis of different processing networks using superstructure optimization. The methodology can handle different network optimization problems of various application fields. It integrates databases with a common data architecture...

  13. Integral ceramic superstructure evaluation using time domain optical coherence tomography (United States)

    Sinescu, Cosmin; Bradu, Adrian; Topala, Florin I.; Negrutiu, Meda Lavinia; Duma, Virgil-Florin; Podoleanu, Adrian G.


    Optical Coherence Tomography (OCT) is a non-invasive low coherence interferometry technique that includes several technologies (and the corresponding devices and components), such as illumination and detection, interferometry, scanning, adaptive optics, microscopy and endoscopy. From its large area of applications, we consider in this paper a critical aspect in dentistry - to be investigated with a Time Domain (TD) OCT system. The clinical situation of an edentulous mandible is considered; it can be solved by inserting 2 to 6 implants. On these implants a mesostructure will be manufactured and on it a superstructure is needed. This superstructure can be integral ceramic; in this case materials defects could be trapped inside the ceramic layers and those defects could lead to fractures of the entire superstructure. In this paper we demonstrate that a TD-OCT imaging system has the potential to properly evaluate the presence of the defects inside the ceramic layers and those defects can be fixed before inserting the prosthesis inside the oral cavity. Three integral ceramic superstructures were developed by using a CAD/CAM technology. After the milling, the ceramic layers were applied on the core. All the three samples were evaluated by a TD-OCT system working at 1300 nm. For two of the superstructures evaluated, no defects were found in the most stressed areas. The third superstructure presented four ceramic defects in the mentioned areas. Because of those defects the superstructure may fracture. The integral ceramic prosthesis was send back to the dental laboratory to fix the problems related to the material defects found. Thus, TD-OCT proved to be a valuable method for diagnosing the ceramic defects inside the integral ceramic superstructures in order to prevent fractures at this level.

  14. Superstructures in Rayleigh-Benard convection (United States)

    Stevens, Richard; Verzicco, Roberto; Lohse, Detlef


    We study the heat transfer and the flow structures in Rayleigh-Bénard convection as function of the Rayleigh number Ra and the aspect ratio. We consider three-dimensional direct numerical simulations (DNS) in a laterally periodic geometry with aspect ratios up to Γ =Lx /Lz =Ly /Lz = 64 at Ra =108 , where Lx and Ly indicate the horizontal domain sizes and Lz the height. We find that the heat transport convergences relatively quickly with increasing aspect ratio. In contrast, we find that the large scale flow structures change significantly with increasing aspect ratio due to the formation of superstructures. For example, at Ra =108 we find the formation of basically only one large scale circulation roll in boxes with an aspect ratio up to 8. For larger boxes we find the formation of multiple of these extremely large convection rolls. We illustrate this by movies of horizontal cross-section of the bulk and the boundary layer and analyze them by using spectra in the boundary layer and the bulk. In addition, we study the effect of the large scale flow structures on the mean and higher order temperature and velocity statistics in the boundary layer and the bulk by comparing the simulation results obtained in different aspect ratio boxes. Foundation for fundamental Research on Matter (FOM), Netherlands Center for Multiscale Catalytic Energy Conversion (MCEC), SURFsara, Gauss Large Scale project.

  15. Particle suspension in sediment-laden flow

    Institute of Scientific and Technical Information of China (English)


    Many theories have been developed for predicting the vertical profiles of suspended sediment concentration in sediment-laden flows. An overview of various recent investigations is given herein. The generalization of the existing formulas and the interpretation of the typical sediment distributions are discussed in terms of continuum and kinetic concepts. The continuum assumption, which has been proved very successful for descriptions of liquid fluid motion, seems insufficient to describe motions of discrete solid particles in two-phase flows. Stochastic models can be used to approach the motion of the individual particles in the fluid, but are unsuitable for simulating interactions between solid particles. The analogy of kinetic theory in sediment-laden flows offers a promising alternative approach, and is expected for the applications in hyper-concentrated flow studies.

  16. Transition in particle-laden flows


    Klinkenberg, J Joy


    This thesis presents the study of laminar to turbulent transition of particle laden flows. When a flow becomes turbulent, the drag increases one order of magnitude compared to a laminar flow, therefore, much research is devoted to understand and influence the transition. Previous research at the Linne Flow Centre at KTH has concentrated on the understanding of the bypass transition process of single-phase fluids. Though there are still questions, the principles of this process are now, more o...

  17. Process for treating moisture laden coal fines (United States)

    Davis, Burl E.; Henry, Raymond M.; Trivett, Gordon S.; Albaugh, Edgar W.


    A process is provided for making a free flowing granular product from moisture laden caked coal fines, such as wet cake, by mixing a water immiscible substance, such as oil, with the caked coal, preferably under low shear forces for a period of time sufficient to produce a plurality of free flowing granules. Each granule is preferably comprised of a dry appearing admixture of one or more coal particle, 2-50% by weight water and the water immiscible substance.

  18. Superstructure optimization of biodiesel production from microalgal biomass

    DEFF Research Database (Denmark)

    Rizwan, Muhammad; Lee, Jay H.; Gani, Rafiqul


    In this study, we propose a mixed integer nonlinear programming (MINLP) model for superstructure based optimization of biodiesel production from microalgal biomass. The proposed superstructure includes a number of major processing steps for the production of biodiesel from microalgal biomass...... for the production of biodiesel from microalgae. The proposed methodology is tested by implementing on a specific case study. The MINLP model is implemented and solved in GAMS using a database built in Excel. The results from the optimization are analyzed and their significances are discussed....

  19. Modifications of the superstructure for the staple implant. (United States)

    Guerra, L R; Larsen, H D; Finger, I M; Jaen, F


    Two techniques have been described to expedite fabrication and reduce the cost of prostheses made for staple implants. The techniques permit placement of a simulated transosseous pin within the master cast. At the time of denture placement in technique No. 1, the coping-bar attachment assembly is cemented (Fig. 12). In technique No. 2 the superstructure is placed over the transosteal pins and secured between the locknuts to maintain the base of the lower locknut 1.5 mm from the crest of the alveolar ridge (Fig. 13). Technique No. 2 permits removal of the superstructure as desired. Patients should be instructed in proper oral hygiene and denture care.

  20. LES of droplet-laden non-isothermal channel flow

    NARCIS (Netherlands)

    Michalek, W.R.; Liew, R.; Kuerten, J.G.M.; Zeegers, J.C.H.


    In this paper subgrid models for LES of droplet-laden non-isothermal channel flow are tested and improved for three Reynolds numbers based on friction velocity, Reτ of 150, 395, and 950 with the aim to develop a simulation method for LES of a droplet-laden Ranque-Hilsch vortex tube. A new subgrid mo

  1. 49 CFR 176.92 - Cylinders laden in vehicles. (United States)


    ... 49 Transportation 2 2010-10-01 2010-10-01 false Cylinders laden in vehicles. 176.92 Section 176.92... Requirements for Transport Vehicles Loaded With Hazardous Materials and Transported on Board Ferry Vessels § 176.92 Cylinders laden in vehicles. Any cylinder of Class 2 (compressed gas) material which...

  2. Templated and template-free fabrication strategies for zero-dimensional hollow MOF superstructures. (United States)

    Kim, Hyehyun; Lah, Myoung Soo


    Various fabrication strategies for hollow metal-organic framework (MOF) superstructures are reviewed and classified using various types of external templates and their properties. Hollow MOF superstructures have also been prepared without external templates, wherein unstable intermediates obtained during reactions convert to the final hollow MOF superstructures. Many hollow MOF superstructures have been fabricated using hard templates. After the core-shell core@MOF structure was prepared using a hard template, the core was selectively etched to generate a hollow MOF superstructure. Another approach for generating hollow superstructures is to use a solid reactant as a sacrificial template; this method requires no additional etching process. Soft templates such as discontinuous liquid/emulsion droplets and gas bubbles in a continuous soft phase have also been employed to prepare hollow MOF superstructures.


    Institute of Scientific and Technical Information of China (English)



    Laboratory experiments on longitudinal dispersion in clear-water and sediment-laden open channel flows are reported. Data from these experiments and those available from previous studies indicate that the suspended sediment present in the flow affects the longitudinal dispersion process. The observed velocity distributions over the depth of sediment-laden flows indicate that the velocity deviates from the mean velocity more in sediment-laden flows than in clear-water flows. The velocity distributions over the cross section and secondary flow in the channel are also expected to be altered due to the presence of suspended sediments in the flow. For these reasons, more dispersion is found in sediment-laden flows than in corresponding clear-water flows. A predictor for the dispersion coefficient in sediment-laden flows is proposed.

  4. Direct simulation of particle-laden fluids

    Energy Technology Data Exchange (ETDEWEB)



    Processes that involve particle-laden fluids are common in geomechanics and especially in the petroleum industry. Understanding the physics of these processes and the ability to predict their behavior requires the development of coupled fluid-flow and particle-motion computational methods. This paper outlines an accurate and robust coupled computational scheme using the lattice-Boltzmann method for fluid flow and the discrete-element method for solid particle motion. Results from several two-dimensional validation simulations are presented. Simulations reported include the sedimentation of an ellipse, a disc and two interacting discs in a closed column of fluid. The recently discovered phenomenon of drafting, kissing, and tumbling is fully reproduced in the two-disc simulation.

  5. The impact of superstructures in the Cosmic Microwave Background (United States)

    Ilić, Stéphane; Langer, Mathieu; Douspis, Marian


    In 2008, Granett et al. claimed a direct detection of the integrated Sachs-Wolfe (iSW) effect, through the stacking of CMB patches at the positions of identified superstructures. Additionally, the high amplitude of their measured signal was reported to be at odds with predictions from the standard model of cosmology. However, a closer inspection of these results prompts multiple questions, more specifically about the amplitude and significance of the expected signal. We propose here an original theoretical prediction of the iSW effect produced by such superstructures. We use simulations based on GR and the LTB metric to reproduce cosmic structures and predict their exact theoretical iSW effect on the CMB. The amplitudes predicted with this method are consistent with the signal measured when properly accounting the contribution of the non-negligible (and fortuitous) primordial CMB fluctuations to the total signal. It also highlights the tricky nature of stacking measurements and their interpretation.

  6. Superstructure Strategy: Do Indonesian EFL Learners Use It?

    Directory of Open Access Journals (Sweden)

    Evy C Ridwan


    Full Text Available Abstract: This paper reports on a study conducted among Indonesian undergraduate students majoring in English as a Foreign Language (EFL. One strategy that learners generally use to understand the main ideas of an expository text is the superstructure strategy (i.e., utilizing the text structure to understand the main ideas. While research in English as First Language reading has demonstrated the benefit of using this strategy, little do we know whether Indonesian EFL learners use this strategy in reading and whether this strategy is beneficial to them or not. Two versions of an expository text were developed: One version had an explicit text structure, with the inclusion of discourse markers, to elicit learners to use the superstructure strategy; the other was without discourse markers. It was hypothesized that learners who read the version with an explicit text structure would utilize the superstructure strategy thereby comprehending main ideas better than those who read the other version. Additionally, to confirm the hypothesis learners were also asked to answer a questionnaire developed from O'Malley and Chamot (1993 followed by an interview to find out if EFL learners used other strategies to comprehend main ideas.

  7. Particle-Laden Viscous Gravity Currents (United States)

    Saha, Sandeep; Talon, Laurent; Salin, Dominique; Porous Media Team


    The extension of a gravity current in lock-exchange problems, proceeds as square root of time in the viscous regime. In the presence of particles, however, this scenario is drastically altered due to sedimentation in a manner similar to the well- known Boycott effect. The spreading of particle-laden gravity currents is investigated with numerical simulations based on a Lattice-Boltzmann method. The settling of particles is modelled using a flux function for capturing sudden discontinuities in particle concentration travelling as kinematic shock waves. Contrary to conventional gravity currents, sedimentation leads to the formation of two additional fronts: a horizontal front descending vertically and a sediment layer that ascends as the particles accumulate. Two regimes emerge in the spreading process: the latter corresponding to the lateral advance of the sediment deposit and the former characterised by the vertical motion of the two fronts. An increase in the initial concentration hastens the time at which the regime change occurs and impedes the overall spreading process. The sedimentation velocity of the particles either slows down or speeds up the edges of the gravity current. A model based on lubrication theory is derived to explain the results and identify scaling laws.

  8. Garden-like perovskite superstructures with enhanced photocatalytic activity. (United States)

    Ye, Meidan; Wang, Mengye; Zheng, Dajiang; Zhang, Nan; Lin, Changjian; Lin, Zhiqun


    By subjecting amorphous flower-like TiO2 to a facile hydrothermal synthesis in the presence of Sr(2+), garden-like perovskite SrTiO3 superstructures were achieved. The amorphous TiO2 was preformed using ZnO flowers as templates. Different three-dimensional SrTiO3 architectures were coexisted in the garden, including SrTiO3 flowers composed of several hollow sword-shaped petals, many sheet-shaped petals or numerous flake-shaped petals, and SrTiO3 grass consisting of a number of long blades. These SrTiO3 superstructures were simultaneously grown on fluorine-doped tin oxide (FTO) substrates. On the basis of a comprehensive study on the effects of growth time, temperature, initial concentrations of precursor, and pH, the formation of these various hierarchical architectures was attributed primarily to the dissolution of amorphous TiO2 and precipitation of perovskite crystals, followed by the Ostwald ripening process of perovskite nanocrystals and self-organization of perovskite building blocks. Interestingly, this approach can be readily extended to create other perovskite structures, including dendritic BaTiO3 and nest-like CaTiO3, as well as PbTiO3 transformed from plate-like pyrochlore Pb2Ti2O6 after post-thermal treatment. Garden-like SrTiO3 superstructures showed a superior photocatalytic performance when compared to other as-prepared semiconductors and perovskite materials (i.e., ZnO, TiO2, BaTiO3, CaTiO3 and PbTiO3), probably due to their intrinsic photocatalytic activity and special garden-like features with a coexistence of various structures that significantly facilitated the adsorption and diffusion of methyl blue (MB) molecules and oxygen species in the photochemical reaction of MB degradation.

  9. Imprint of DES superstructures on the cosmic microwave background (United States)

    Kovács, A.; Sánchez, C.; García-Bellido, J.; Nadathur, S.; Crittenden, R.; Gruen, D.; Huterer, D.; Bacon, D.; Clampitt, J.; DeRose, J.; Dodelson, S.; Gaztañaga, E.; Jain, B.; Kirk, D.; Lahav, O.; Miquel, R.; Naidoo, K.; Peacock, J. A.; Soergel, B.; Whiteway, L.; Abdalla, F. B.; Allam, S.; Annis, J.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Rosell, A. Carnero; Carrasco Kind, M.; Carretero, J.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Eifler, T. F.; Finley, D. A.; Flaugher, B.; Fosalba, P.; Frieman, J.; Giannantonio, T.; Goldstein, D. A.; Gruendl, R. A.; Gutierrez, G.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Marshall, J. L.; Melchior, P.; Menanteau, F.; Nord, B.; Ogando, R.; Plazas, A. A.; Romer, A. K.; Sanchez, E.; Scarpine, V.; Sevilla-Noarbe, I.; Sobreira, F.; Suchyta, E.; Swanson, M.; Tarle, G.; Thomas, D.; Walker, A. R.; DES Collaboration


    Small temperature anisotropies in the cosmic microwave background (CMB) can be sourced by density perturbations via the late-time integrated Sachs-Wolfe (ISW) effect. Large voids and superclusters are excellent environments to make a localized measurement of this tiny imprint. In some cases excess signals have been reported. We probed these claims with an independent data set, using the first year data of the Dark Energy Survey (DES) in a different footprint, and using a different superstructure finding strategy. We identified 52 large voids and 102 superclusters at redshifts 0.2 < z < 0.65. We used the Jubilee simulation to a priori evaluate the optimal ISW measurement configuration for our compensated top-hat filtering technique, and then performed a stacking measurement of the CMB temperature field based on the DES data. For optimal configurations, we detected a cumulative cold imprint of voids with ΔTf ≈ -5.0 ± 3.7 μK and a hot imprint of superclusters ΔTf ≈ 5.1 ± 3.2 μK; this is ∼1.2σ higher than the expected |ΔTf| ≈ 0.6 μK imprint of such superstructures in Λ cold dark matter (ΛCDM). If we instead use an a posteriori selected filter size (R/Rv = 0.6), we can find a temperature decrement as large as ΔTf ≈ -9.8 ± 4.7 μK for voids, which is ∼2σ above ΛCDM expectations and is comparable to previous measurements made using Sloan Digital Sky Survey superstructure data.

  10. Imprint of DES superstructures on the cosmic microwave background

    Energy Technology Data Exchange (ETDEWEB)

    Kovács, A.; Sánchez, C.; García-Bellido, J.; Nadathur, S.; Crittenden, R.; Gruen, D.; Huterer, D.; Bacon, D.; Clampitt, J.; DeRose, J.; Dodelson, S.; Gaztañaga, E.; Jain, B.; Kirk, D.; Lahav, O.; Miquel, R.; Naidoo, K.; Peacock, J. A.; Soergel, B.; Whiteway, L.; Abdalla, F. B.; Allam, S.; Annis, J.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Rosell, A. Carnero; Carrasco Kind, M.; Carretero, J.; Cunha, C. E.; D' Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Eifler, T. F.; Finley, D. A.; Flaugher, B.; Fosalba, P.; Frieman, J.; Giannantonio, T.; Goldstein, D. A.; Gruendl, R. A.; Gutierrez, G.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Marshall, J. L.; Melchior, P.; Menanteau, F.; Nord, B.; Ogando, R.; Plazas, A. A.; Romer, A. K.; Sanchez, E.; Scarpine, V.; Sevilla-Noarbe, I.; Sobreira, F.; Suchyta, E.; Swanson, M.; Tarle, G.; Thomas, D.; Walker, A. R.


    Small temperature anisotropies in the Cosmic Microwave Background can be sourced by density perturbations via the late-time integrated Sachs-Wolfe effect. Large voids and superclusters are excellent environments to make a localized measurement of this tiny imprint. In some cases excess signals have been reported. We probed these claims with an independent data set, using the first year data of the Dark Energy Survey in a different footprint, and using a different super-structure finding strategy. We identified 52 large voids and 102 superclusters at redshifts $0.2 < z < 0.65$. We used the Jubilee simulation to a priori evaluate the optimal ISW measurement configuration for our compensated top-hat filtering technique, and then performed a stacking measurement of the CMB temperature field based on the DES data. For optimal configurations, we detected a cumulative cold imprint of voids with $\\Delta T_{f} \\approx -5.0\\pm3.7~\\mu K$ and a hot imprint of superclusters $\\Delta T_{f} \\approx 5.1\\pm3.2~\\mu K$ ; this is $\\sim1.2\\sigma$ higher than the expected $|\\Delta T_{f}| \\approx 0.6~\\mu K$ imprint of such super-structures in $\\Lambda$CDM. If we instead use an a posteriori selected filter size ($R/R_{v}=0.6$), we can find a temperature decrement as large as $\\Delta T_{f} \\approx -9.8\\pm4.7~\\mu K$ for voids, which is $\\sim2\\sigma$ above $\\Lambda$CDM expectations and is comparable to previous measurements made using SDSS super-structure data.

  11. A Generic Methodology for Superstructure Optimization of Different Processing Networks

    DEFF Research Database (Denmark)

    Bertran, Maria-Ona; Frauzem, Rebecca; Zhang, Lei;


    In this paper, we propose a generic computer-aided methodology for synthesis of different processing networks using superstructure optimization. The methodology can handle different network optimization problems of various application fields. It integrates databases with a common data architecture......, a generic model to represent the processing steps, and appropriate optimization tools. A special software interface has been created to automate the steps in the methodology workflow, allow the transfer of data between tools and obtain the mathematical representation of the problem as required...

  12. Magnetic-Field-Assisted Assembly of Anisotropic Superstructures by Iron Oxide Nanoparticles and Their Enhanced Magnetism. (United States)

    Jiang, Chengpeng; Leung, Chi Wah; Pong, Philip W T


    Magnetic nanoparticle superstructures with controlled magnetic alignment and desired structural anisotropy hold promise for applications in data storage and energy storage. Assembly of monodisperse magnetic nanoparticles under a magnetic field could lead to highly ordered superstructures, providing distinctive magnetic properties. In this work, a low-cost fabrication technique was demonstrated to assemble sub-20-nm iron oxide nanoparticles into crystalline superstructures under an in-plane magnetic field. The gradient of the applied magnetic field contributes to the anisotropic formation of micron-sized superstructures. The magnitude of the applied magnetic field promotes the alignment of magnetic moments of the nanoparticles. The strong dipole-dipole interactions between the neighboring nanoparticles lead to a close-packed pattern as an energetically favorable configuration. Rod-shaped and spindle-shaped superstructures with uniform size and controlled spacing were obtained using spherical and polyhedral nanoparticles, respectively. The arrangement and alignment of the superstructures can be tuned by changing the experimental conditions. The two types of superstructures both show enhancement of coercivity and saturation magnetization along the applied field direction, which is presumably associated with the magnetic anisotropy and magnetic dipole interactions of the constituent nanoparticles and the increased shape anisotropy of the superstructures. Our results show that the magnetic-field-assisted assembly technique could be used for fabricating nanomaterial-based structures with controlled geometric dimensions and enhanced magnetic properties for magnetic and energy storage applications.

  13. 40 CFR 745.228 - Accreditation of training programs: public and commercial buildings, bridges and superstructures... (United States)


    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Accreditation of training programs: public and commercial buildings, bridges and superstructures. 745.228 Section 745.228 Protection of... of training programs: public and commercial buildings, bridges and superstructures....

  14. Cation ordering and superstructures in natural layered double hydroxides. (United States)

    Krivovichev, Sergey V; Yakovenchuk, Victor N; Zolotarev, Andrey A; Ivanyuk, Gregory N; Pakhomovsky, Yakov A


    Layered double hydroxides (LDHs) constitute an important group of materials with many applications ranging from catalysis and absorption to carriers for drug delivery, DNA intercalation and carbon dioxide sequestration. The structures of LDHs are based upon double brucite-like hydroxide layers [M(2+)(n)M(3+)(m)(OH)(2(m+n)](m+), where M(2+) = Mg(2+), Fe(2+), Mn(2+), Zn(2+), etc.; M(3+) = Al(3+), Fe(3+), Cr(3+), Mn(3+), etc. Structural features of LDHs such as cation ordering, charge distribution and polytypism have an immediate influence upon their properties. However, all the structural studies on synthetic LDHs deal with powder samples that prevent elucidation of such fine details of structure architecture as formation of superstructures due to cation ordering. In contrast to synthetic materials, natural LDHs are known to form single crystals accessible to single-crystal X-ray diffraction analysis, which provides a unique possibility to investigate 3D cation ordering in LDHs that results in formation of complex superstructures, where 2D cation order is combined with a specific order of layer stacking (polytypism). Therefore LDH minerals provide an indispensable source of structural information for modeling of structures and processes happening in LDHs at the molecular and nanoscale levels.

  15. Abnormal Congenital Location of Stapes' Superstructure: Clinical and Embryological Implications (United States)

    Teles, Rafaela; Sousa, Ana; Estevão, Roberto; Rodrigues, Jorge; Gomes, Alexandra; Silva, Francisco; Fernandes, Ângelo; Fernandes, Fausto


    Congenital middle ear malformations are rare. Most part of them are usually associated with other malformations, such as aural atresia, microtia, and dysmorphic craniofacial features. A clinical case of a 24-year-old male with a right-sided conductive hearing loss since his childhood, without craniofacial malformation, is presented. He was proposed for exploratory tympanotomy under the suspicious diagnosis of otosclerosis. The surgery revealed an abnormal location of stapes' superstructure, which was attached to the promontory and had an isolated and mobile osseous footplate in the oval window. A stapes prosthesis was inserted and resulted in closure of the air-bone gap by 25 dB. A review of the literature was also performed using MEDLINE. Two theories diverge on the embryologic origin of the stapes. Our findings seem to be in favour of the theory that defines two different embryologic origins to the stapes. PMID:27648330

  16. Synthesis of biorefinery networks using a superstructure optimization based approach

    DEFF Research Database (Denmark)

    Bertran, Maria-Ona; Anaya-Reza, Omar; Lopez-Arenas, Maria Teresa

    into account the available technologies, geographical location, future technological developments and global market changes. The problem of optimal design of biorefinery networks is solved in this work through three different stages: (i) synthesis stage, (ii) design stage, and (iii) innovation stage......]. The optimal synthesis of biorefinery networks problem is defined as: given a set of biomass derived feedstock and a set of desired final products and specifications, determine a flexible, sustainable and innovative processing network with the targets of minimum cost and sustainable development taking....... At the synthesis stage, the considered alternatives are represented in a superstructure, from which a mixed-integer linear or nonlinear programming (MILP or MINLP) problem is derived and solved in order to find the optimal processing network for a pre-defined objective function. Next, at the design stage...

  17. Abnormal Congenital Location of Stapes’ Superstructure: Clinical and Embryological Implications

    Directory of Open Access Journals (Sweden)

    Vânia Henriques


    Full Text Available Congenital middle ear malformations are rare. Most part of them are usually associated with other malformations, such as aural atresia, microtia, and dysmorphic craniofacial features. A clinical case of a 24-year-old male with a right-sided conductive hearing loss since his childhood, without craniofacial malformation, is presented. He was proposed for exploratory tympanotomy under the suspicious diagnosis of otosclerosis. The surgery revealed an abnormal location of stapes’ superstructure, which was attached to the promontory and had an isolated and mobile osseous footplate in the oval window. A stapes prosthesis was inserted and resulted in closure of the air-bone gap by 25 dB. A review of the literature was also performed using MEDLINE. Two theories diverge on the embryologic origin of the stapes. Our findings seem to be in favour of the theory that defines two different embryologic origins to the stapes.

  18. Final restoration of implants with a hybrid ceramic superstructure. (United States)

    Kurbad, Andreas

    The use of materials with elastic properties for the fabrication of dental implant superstructures seems to be a promising way to reduce the functional occlusal forces on implants. Vita Enamic (Vita Zahnfabrik, Bad Säckingen), a hybrid ceramic material for CAD/CAM technology, is available in a special form that can be relatively easily combined with titanium (Ti) base connectors for the fabrication of abutment crowns and mesostructures. Thus, an easily manageable method is available for reducing peak loads on dental implant fixtures. Representative cases are presented to demonstrate the clinical workflows for a single- element solution (Ti base) and two-element solution (Ti base with mesostructure) for implant-supported crowns.

  19. Garden-like perovskite superstructures with enhanced photocatalytic activity (United States)

    Ye, Meidan; Wang, Mengye; Zheng, Dajiang; Zhang, Nan; Lin, Changjian; Lin, Zhiqun


    By subjecting amorphous flower-like TiO2 to a facile hydrothermal synthesis in the presence of Sr2+, garden-like perovskite SrTiO3 superstructures were achieved. The amorphous TiO2 was preformed using ZnO flowers as templates. Different three-dimensional SrTiO3 architectures were coexisted in the garden, including SrTiO3 flowers composed of several hollow sword-shaped petals, many sheet-shaped petals or numerous flake-shaped petals, and SrTiO3 grass consisting of a number of long blades. These SrTiO3 superstructures were simultaneously grown on fluorine-doped tin oxide (FTO) substrates. On the basis of a comprehensive study on the effects of growth time, temperature, initial concentrations of precursor, and pH, the formation of these various hierarchical architectures was attributed primarily to the dissolution of amorphous TiO2 and precipitation of perovskite crystals, followed by the Ostwald ripening process of perovskite nanocrystals and self-organization of perovskite building blocks. Interestingly, this approach can be readily extended to create other perovskite structures, including dendritic BaTiO3 and nest-like CaTiO3, as well as PbTiO3 transformed from plate-like pyrochlore Pb2Ti2O6 after post-thermal treatment. Garden-like SrTiO3 superstructures showed a superior photocatalytic performance when compared to other as-prepared semiconductors and perovskite materials (i.e., ZnO, TiO2, BaTiO3, CaTiO3 and PbTiO3), probably due to their intrinsic photocatalytic activity and special garden-like features with a coexistence of various structures that significantly facilitated the adsorption and diffusion of methyl blue (MB) molecules and oxygen species in the photochemical reaction of MB degradation.By subjecting amorphous flower-like TiO2 to a facile hydrothermal synthesis in the presence of Sr2+, garden-like perovskite SrTiO3 superstructures were achieved. The amorphous TiO2 was preformed using ZnO flowers as templates. Different three-dimensional SrTiO3

  20. Bin Laden sekkus USA valimisvõitlusesse / Neeme Raud

    Index Scriptorium Estoniae

    Raud, Neeme, 1969-


    Terroripealik Osama bin Laden pöördus 29. oktoobril meedia vahendusel ameeriklaste poole ning märkis, et kui USA soovib vältida uusi 11. septembri laadseid rünnakuid, peab ta lõpetama moslemite julgeoleku ohustamise

  1. Large Eddy Simulation of jets laden with evaporating drops (United States)

    Leboissetier, A.; Okong'o, N.; Bellan, J.


    LES of a circular jet laden with evaporating liquid drops are conducted to assess computational-drop modeling and three different SGS-flux models: the Scale Similarity model (SSC), using a constant coefficient calibrated on a temporal mixing layer DNS database, and dynamic-coefficient Gradient and Smagorinsky models.

  2. Polymer Micelles Laden Hydrogel Contact Lenses for Ophthalmic Drug Delivery. (United States)

    Hu, Xiaohong; Tan, Huaping; Chen, Pin; Wang, Xin; Pang, Juan


    Hydrogel contact lens is an attractive drug carrier for the delivery of ophthalmic drugs. But limited drug loading capacity and burst release restricted its application in this field. Polymer micelle laden hydrogel contact lenses were designed for ophthalmic drug delivery in the work. β-CD/PAA/PEG ternary system was chosen to form polymer micelle. The micelle size could be adjusted by β-CD content and PAA/PEG concentration. The zeta potential of micelle was irrelevant to β-CD content, but influenced by PAA/PEG concentration. The absorbed drug concentration in micelle solution depended on both β-CD content and PAA/PEG concentration. Polymer micelle laden hydrogels were obtained by radical polymerization in situ. The transparency of polymer micelle laden hydrogel declined with PAA/PEG concentration increasing. The equilibrium water content and water loss showed that polymer micelle laden hydrogel with higher PAA/PEG concentration was in a higher swollen state. The dynamic viscoelastic properties howed that all polymer micelle laden hydrogels had some characteristics of crosslinked elastomers. The surface structure of freeze dried composite hydrogels was different from freeze dried pure hydrogel. The drug loading and releasing behaviors were detected to evaluate the drug loading and releasing capacity of hydrogels using orfloxacin and puerarin as model drugs. The results indicated the polymer micelle in hydrogel could hold or help to hold some ophthalmic drugs, and slow down orfloxacin release speed or keep puerarin stably stay for a time in hydrogels. In the end, it was found that the transparency of composite hydrogel became better after the hydrogel had been immersed in PBS for several weeks.

  3. Design and application of inorganic nanoparticle superstructures: current status and future challenges. (United States)

    Gao, Yan; Tang, Zhiyong


    Self-assembly of inorganic nanoparticles (NPs) into superstructures, which is used as a general way to integrate functional inorganic NPs into macroscale devices, has attracted much research interest. This review will summarize the recent progress and discuss future challenges of the inorganic NP superstructures. Examples include both DNA-based and polymer-based NP assemblies with controlled positioning and geometries, and quasicrystalline ordered structures from the self-assembly of binary or ternary NPs. Different from their individual NP counterparts, these self-assembled superstructures possess unique properties, such as optical chirality and dynamic structural change under an external stimulus. Due to their diversified structures and functionalities, inorganic NP superstructures have shown a wide range of promise for applications in electronic and photonic devices, such as field-effect transistors, magnetoresistive components, optical information recording, and solar cells.

  4. Recrystallization-induced self-assembly for the growth of Cu₂O superstructures. (United States)

    Shang, Yang; Shao, Yi-Ming; Zhang, Dong-Feng; Guo, Lin


    The assembly of inorganic nanoparticles (NPs) into 3D superstructures with defined morphologies is of particular interest. A novel strategy that is based on recrystallization-induced self-assembly (RISA) for the construction of 3D Cu2O superstructures and employs Cu2O mesoporous spheres with diameters of approximately 300 nm as the building blocks has now been developed. Balancing the hydrolysis and recrystallization rates of the CuCl precursors through precisely adjusting the experimental parameters was key to success. Furthermore, the geometry of the superstructures can be tuned to obtain either cubes or tetrahedra and was shown to be dependent on the growth behavior of bulk CuCl. The overall strategy extends the applicability of recrystallization-based processes for the guided construction of assemblies and offers unique insights for assembling larger particles into complicated 3D superstructures.

  5. Joint Simultaneous Reconstruction of Regularized Building Superstructures from Low-Density LIDAR Data Using Icp (United States)

    Wichmann, Andreas; Kada, Martin


    There are many applications for 3D city models, e.g., in visualizations, analysis, and simulations; each one requiring a certain level of detail to be effective. The overall trend goes towards including various kinds of anthropogenic and natural objects therein with ever increasing geometric and semantic details. A few years back, the featured 3D building models had only coarse roof geometry. But nowadays, they are expected to include detailed roof superstructures like dormers and chimneys. Several methods have been proposed for the automatic reconstruction of 3D building models from airborne based point clouds. However, they are usually unable to reliably recognize and reconstruct small roof superstructures as these objects are often represented by only few point measurements, especially in low-density point clouds. In this paper, we propose a recognition and reconstruction approach that overcomes this problem by identifying and simultaneously reconstructing regularized superstructures of similar shape. For this purpose, candidate areas for superstructures are detected by taking into account virtual sub-surface points that are assumed to lie on the main roof faces below the measured points. The areas with similar superstructures are detected, extracted, grouped together, and registered to one another with the Iterative Closest Point (ICP) algorithm. As an outcome, the joint point density of each detected group is increased, which helps to recognize the shape of the superstructure more reliably and in more detail. Finally, all instances of each group of superstructures are modeled at once and transformed back to their original position. Because superstructures are reconstructed in groups, symmetries, alignments, and regularities can be enforced in a straight-forward way. The validity of the approach is presented on a number of example buildings from the Vaihingen test data set.

  6. Antisolvent crystallization approach to construction of CuI superstructures with defined geometries. (United States)

    Kozhummal, Rajeevan; Yang, Yang; Güder, Firat; Küçükbayrak, Umut M; Zacharias, Margit


    A facile high-yield production of cuprous iodide (CuI) superstructures is reported by antisolvent crystallization using acetonitrile/water as a solvent/antisolvent couple under ambient conditions. In the presence of trace water, the metastable water droplets act as templates to induce the precipitation of hollow spherical CuI superstructures consisting of orderly aligned building blocks after drop coating. With water in excess in the mixed solution, an instant precipitation of CuI random aggregates takes place due to rapid crystal growth via ion-by-ion attachment induced by a strong antisolvent effect. However, this uncontrolled process can be modified by adding polymer polyvinyl pyrrolidone (PVP) in water to restrict the size of initially formed CuI crystal nuclei through the effective coordination effect of PVP. As a result, CuI superstructures with a cuboid geometry are constructed by gradual self-assembly of the small CuI crystals via oriented attachment. The precipitated CuI superstructures have been used as competent adsorbents to remove organic dyes from the water due to their mesocrystal feature. Besides, the CuI superstructures have been applied either as a self-sacrificial template or only as a structuring template for the flexible design of other porous materials such as CuO and TiO2. This system provides an ideal platform to simultaneously investigate the superstructure formation enforced by antisolvent crystallization with and without organic additives.

  7. LES of droplet-laden non-isothermal channel flow (United States)

    Michałek, W. R.; Liew, R.; Kuerten, J. G. M.; Zeegers, J. C. H.


    In this paper subgrid models for LES of droplet-laden non-isothermal channel flow are tested and improved for three Reynolds numbers based on friction velocity, Reτ of 150, 395, and 950 with the aim to develop a simulation method for LES of a droplet-laden Ranque-Hilsch vortex tube. A new subgrid model combining the beneficial properties of the dynamic eddy-viscosity model and the approximate deconvolution model is proposed. Furthermore, the subgrid model in the droplet equations based on approximate deconvolution is found to perform well also in non-isothermal channel flow. At the highest Reynolds number in the test the dynamic model yields results with a similar accuracy as the approximate deconvolution model.

  8. LES of droplet-laden non-isothermal channel flow

    Energy Technology Data Exchange (ETDEWEB)

    Michalek, W R; Kuerten, J G M [Department of Mechanical Engineering, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven (Netherlands); Liew, R; Zeegers, J C H, E-mail: [Department of Applied Physics, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven (Netherlands)


    In this paper subgrid models for LES of droplet-laden non-isothermal channel flow are tested and improved for three Reynolds numbers based on friction velocity, Re{sub {tau}} of 150, 395, and 950 with the aim to develop a simulation method for LES of a droplet-laden Ranque-Hilsch vortex tube. A new subgrid model combining the beneficial properties of the dynamic eddy-viscosity model and the approximate deconvolution model is proposed. Furthermore, the subgrid model in the droplet equations based on approximate deconvolution is found to perform well also in non-isothermal channel flow. At the highest Reynolds number in the test the dynamic model yields results with a similar accuracy as the approximate deconvolution model.

  9. Bilateral Congenital Absence of the Stapes Superstructure in Two Siblings (United States)

    Undabeitia, Jose Ignacio; Undabeitia, José; Cianci, Laura; Padilla, Luis; Petreñas, Eduardo; Municio, Antonio


    Middle ear ossicle malformations are an uncommon event. Among them, the congenital absence of the stapes is a very rare condition that is seldom described in the literature. We report the cases of two women, aged 19 and 22 , who presented with a long history of conductive deafness. An exploratory tympanotomy was performed and the absence of the stapes superstructure and an abnormal position of the facial nerve could be observed. A bone anchored hearing aid (BAHA) was implanted in both patients with good results. It is believed that stapes agenesis is related to an abnormal development of the facial nerve, which by the 5th to 6th week of gestation would interpose between the otic capsule and the stapes blastema, preventing these structures from contacting. A long history of nonprogressive hearing loss from birth or early childhood is the key to reach a diagnosis. Several treatment options have been described. The authors opted for a hearing aid due to the high risk of facial nerve lesion, with good functional results. PMID:25045568

  10. Gellan gum microgel-reinforced cell-laden gelatin hydrogels


    Shin, Hyeongho; Olsen, Bradley D.; Khademhosseini, Ali


    The relatively weak mechanical properties of hydrogels remain a major drawback for their application as load-bearing tissue scaffolds. Previously, we developed cell-laden double-network (DN) hydrogels that were composed of photocrosslinkable gellan gum (GG) and gelatin. Further research into the materials as tissue scaffolds determined that the strength of the DN hydrogels decreased when they were prepared at cell-compatible conditions, and the encapsulated cells in the DN hydrogels did not f...

  11. Light-Directed Dynamic Chirality Inversion in Functional Self-Organized Helical Superstructures. (United States)

    Bisoyi, Hari Krishna; Li, Quan


    Helical superstructures are widely observed in nature, in synthetic polymers, and in supramolecular assemblies. Controlling the chirality (the handedness) of dynamic helical superstructures of molecular and macromolecular systems by external stimuli is a challenging task, but is of great fundamental significance with appealing morphology-dependent applications. Light-driven chirality inversion in self-organized helical superstructures (i.e. cholesteric, chiral nematic liquid crystals) is currently in the limelight because inversion of the handedness alters the chirality of the circularly polarized light that they selectively reflect, which has wide potential for application. Here we discuss the recent developments toward inversion of the handedness of cholesteric liquid crystals enabled by photoisomerizable chiral molecular switches or motors. Different classes of chiral photoresponsive dopants (guests) capable of conferring light-driven reversible chirality inversion of helical superstructures fabricated from different nematic hosts are discussed. Rational molecular designs of chiral molecular switches toward endowing handedness inversion to the induced helical superstructures of cholesteric liquid crystals are highlighted. This Review is concluded by throwing light on the challenges and opportunities in this emerging frontier, and it is expected to provide useful guidelines toward the development of self-organized soft materials with stimuli-directed chirality inversion capability and multifunctional host-guest systems.

  12. Crystallographic superstructure in R2PdSi3 compounds (R=heavy rare earth) (United States)

    Tang, Fei; Frontzek, Matthias; Dshemuchadse, Julia; Leisegang, Tilmann; Zschornak, Matthias; Mietrach, Robert; Hoffmann, Jens-Uwe; Löser, Wolfgang; Gemming, Sibylle; Meyer, Dirk C.; Loewenhaupt, Michael


    The R2PdSi3 intermetallic compounds have been reported to crystallize in a hexagonal AlB2-derived structure, with the rare earth atoms on the Al sites and Pd and Si atoms randomly distributed on the B sites. However, the intricate magnetic properties observed in the series of compounds have always suggested complications to the assumed structure. To clarify the situation, x-ray and neutron diffraction measurements were performed on the heavy rare earth compounds with R=Gd, Tb, Dy, Ho, Er, Tm, which revealed the existence of a crystallographic superstructure. The superstructure features a doubled unit cell in the hexagonal basal plane and an octuplication along the perpendicular c direction with respect to the primitive cell. No structural transition was observed between 300 and 1.5 K. Extended x-ray absorption fine structure (EXAFS) analysis as well as density functional theory (DFT) calculations were utilized to investigate the local environments of the respective atoms. In this paper the various experimental results will be presented and it will be shown that the superstructure is mainly due to the Pd-Si order on the B sites. A structure model will be proposed to fully describe the superstructure of Pd-Si order in R2PdSi3. The connection between the crystallographic superstructure and the magnetic properties will be discussed in the framework of the presented model.

  13. Linking experiment and theory for three-dimensional networked binary metal nanoparticle-triblock terpolymer superstructures (United States)

    Li, Zihui; Hur, Kahyun; Sai, Hiroaki; Higuchi, Takeshi; Takahara, Atsushi; Jinnai, Hiroshi; Gruner, Sol M.; Wiesner, Ulrich


    Controlling superstructure of binary nanoparticle mixtures in three dimensions from self-assembly opens enormous opportunities for the design of materials with unique properties. Here we report on how the intimate coupling of synthesis, in-depth electron tomographic characterization and theory enables exquisite control of superstructure in highly ordered porous three-dimensional continuous networks from single and binary mixtures of metal nanoparticles with a triblock terpolymer. Poly(isoprene-block-styrene-block-(N,N-dimethylamino)ethyl methacrylate) is synthesized and used as structure-directing agent for ligand-stabilized platinum and gold nanoparticles. Quantitative analysis provides insights into short- and long-range nanoparticle-nanoparticle correlations, and local and global contributions to structural chirality in the networks. Results provide synthesis criteria for next-generation mesoporous network superstructures from binary nanoparticle mixtures for potential applications in areas including catalysis.

  14. Linking experiment and theory for three-dimensional networked binary metal nanoparticle–triblock terpolymer superstructures

    KAUST Repository

    Li, Zihui


    © 2014 Macmillan Publishers Limited. Controlling superstructure of binary nanoparticle mixtures in three dimensions from self-assembly opens enormous opportunities for the design of materials with unique properties. Here we report on how the intimate coupling of synthesis, in-depth electron tomographic characterization and theory enables exquisite control of superstructure in highly ordered porous three-dimensional continuous networks from single and binary mixtures of metal nanoparticles with a triblock terpolymer. Poly(isoprene-block-styrene-block-(N,N-dimethylamino)ethyl methacrylate) is synthesized and used as structure-directing agent for ligand-stabilized platinum and gold nanoparticles. Quantitative analysis provides insights into short-and long-range nanoparticle-nanoparticle correlations, and local and global contributions to structural chirality in the networks. Results provide synthesis criteria for next-generation mesoporous network superstructures from binary nanoparticle mixtures for potential applications in areas including catalysis.

  15. Abstraction Super-structuring Normal Forms: Towards a Theory of Structural Induction

    CERN Document Server

    Silvescu, Adrian


    Induction is the process by which we obtain predictive laws or theories or models of the world. We consider the structural aspect of induction. We answer the question as to whether we can find a finite and minmalistic set of operations on structural elements in terms of which any theory can be expressed. We identify abstraction (grouping similar entities) and super-structuring (combining topologically e.g., spatio-temporally close entities) as the essential structural operations in the induction process. We show that only two more structural operations, namely, reverse abstraction and reverse super-structuring (the duals of abstraction and super-structuring respectively) suffice in order to exploit the full power of Turing-equivalent generative grammars in induction. We explore the implications of this theorem with respect to the nature of hidden variables, radical positivism and the 2-century old claim of David Hume about the principles of connexion among ideas.

  16. Large Number, Dark Matter, Dark Energy, and Superstructures in the Universe

    Institute of Scientific and Technical Information of China (English)

    HUANG Wu-Liang; HUANG Xiao-Dong


    Since there may exist dark matter particles v and 5 with mass ~ 10-1 eV in the universe, the superstructures with a scale of 1019 solar masses (large number A ~ 1019) appeared during the era near and before the hydrogen recombination. Since there are superstructures in the universe, there may be no necessity for the existence of dark energy. For checking the superstructure in the universe by CMB anisotropy, we need to measure CMB angular power spectrum -especially around ten degrees across the sky - in more details. While neutrino v is related to electroweak unification, the fourth stable elementary particle δ may be related to strong-gravity unification, which suggests p + p →, n + δ and that some new baryons appeared in the TeV region.

  17. Superstructured Carbon Nanotube/Porous Silicon Hybrid Materials for Lithium-Ion Battery Anodes (United States)

    Lee, Jun-Ki; Kang, Shin-Hyun; Choi, Sung-Min


    High energy Li-ion batteries (LIBs) are in great demand for electronics, electric-vehicles, and grid-scale energy storage. To further increase the energy and power densities of LIBs, Si anodes have been intensively explored due to their high capacity, and high abundance compared with traditional carbon anodes. However, the poor cycle-life caused by large volume expansion during charge/discharge process has been an impediment to its applications. Recently, superstructured Si materials were received attentions to solve above mentioned problem in excellent mechanical properties, large surface area, and fast Li and electron transportation aspects, but applying superstructures to anode is in early stage yet. Here, we synthesized superstructured carbon nanotubes (CNTs)/porous Si hybrid materials and its particular electrochemical properties will be presented. Department of Nuclear and Quantum Engineering

  18. A 3D AgCl hierarchical superstructure synthesized by a wet chemical oxidation method. (United States)

    Lou, Zaizhu; Huang, Baibiao; Ma, Xiangchao; Zhang, Xiaoyang; Qin, Xiaoyan; Wang, Zeyan; Dai, Ying; Liu, Yuanyuan


    A novel 3D AgCl hierarchical superstructure, with fast growth along the 〈111〉 directions of cubic seeds, is synthesized by using a wet chemical oxidation method. The morphological structures and the growth process are investigated by scanning electron microscopy and X-ray diffraction. The crystal structures are analyzed by their crystallographic orientations. The surface energy of AgCl facets {100}, {110}, and {111} with absorbance of Cl(-) ions is studied by density functional theory calculations. Based on the experimental and computational results, a plausible mechanism is proposed to illustrate the formation of the 3D AgCl hierarchical superstructures. With more active sites, the photocatalytic activity of the 3D AgCl hierarchical superstructures is better than those of concave and cubic ones in oxygen evolution under irradiation by visible light.

  19. IHT: Tools for Computing Insolation Absorption by Particle Laden Flows

    Energy Technology Data Exchange (ETDEWEB)

    Grout, R. W.


    This report describes IHT, a toolkit for computing radiative heat exchange between particles. Well suited for insolation absorption computations, it is also has potential applications in combustion (sooting flames), biomass gasification processes and similar processes. The algorithm is based on the 'Photon Monte Carlo' approach and implemented in a library that can be interfaced with a variety of computational fluid dynamics codes to analyze radiative heat transfer in particle-laden flows. The emphasis in this report is on the data structures and organization of IHT for developers seeking to use the IHT toolkit to add Photon Monte Carlo capabilities to their own codes.

  20. Optimal processing pathway for the production of biodiesel from microalgal biomass: A superstructure based approach

    DEFF Research Database (Denmark)

    Rizwan, Muhammad; Lee, Jay H.; Gani, Rafiqul


    In this study, we propose a mixed integer nonlinear programming (MINLP) model for superstructure based optimization of biodiesel production from microalgal biomass. The proposed superstructure includes a number of major processing steps for the production of biodiesel from microalgal biomass...... for the production of biodiesel from microalgae. The proposed methodology is tested by implementing on a specific case with different choices of objective functions. The MINLP model is implemented and solved in GAMS using a database built in Excel. The results from the optimization are analyzed...

  1. Environmental impact assessments of the Xiaolangdi Reservoir on the most hyperconcentrated laden river, Yellow River, China. (United States)

    Kong, Dongxian; Miao, Chiyuan; Wu, Jingwen; Borthwick, Alistair G L; Duan, Qingyun; Zhang, Xiaoming


    The Yellow River is the most hyperconcentrated sediment-laden river in the world. Throughout recorded history, the Lower Yellow River (LYR) experienced many catastrophic flood and drought events. To regulate the LYR, a reservoir was constructed at Xiaolangdi that became operational in the early 2000s. An annual water-sediment regulation scheme (WSRS) was then implemented, aimed at flood control, sediment reduction, regulated water supply, and power generation. This study examines the eco-environmental and socioenvironmental impacts of Xiaolangdi Reservoir. In retrospect, it is found that the reservoir construction phase incurred huge financial cost and required large-scale human resettlement. Subsequent reservoir operations affected the local geological environment, downstream riverbed erosion, evolution of the Yellow River delta, water quality, and aquatic biodiversity. Lessons from the impact assessment of the Xiaolangdi Reservoir are summarized as follows: (1) The construction of large reservoirs is not merely an engineering challenge but must also be viewed in terms of resource exploitation, environmental protection, and social development; (2) long-term systems for monitoring large reservoirs should be established, and decision makers involved at national policy and planning levels must be prepared to react quickly to the changing impact of large reservoirs; and (3) the key to solving sedimentation in the LYR is not Xiaolangdi Reservoir but instead soil conservation in the middle reaches of the Yellow River basin. Proper assessment of the impacts of large reservoirs will help promote development strategies that enhance the long-term sustainability of dam projects.


    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-hua; LONG Wen-fei; LEI Xiao-zhang; ZHANG Xiang-wei; XIE He-ping; WANG Jiang-ping


    This article mainly aims at developing an integrated 2-D numerical simulation model on inundation, sediment transportation and the morphological variations of floodplains due to high sediment-laden inundation flows. Due to the complexity of inner and outer boundaries and the arbitrary structures within the computational domain of floodplains, an unstructured Finite-Volume Method (FVM) based on an irregular polygon mesh was worked out so that the influences of complex boundaries can be integrated into the simulation. A case study was conducted in the Lower Yellow River Basin, in which a dike-break at the Huayuankou Hydrological Station was assumed to happen when a flood scale of 1982 was suffered in the region. The simulated spatial distribution of sediment deposition and erosion can be used to reasonably explain the natural phenomena of "suspended river" of the lower part of the Yellow River. It is concluded that the inundation process of water is similar to a variable-river-bed condition during the simulation because the sediment deposition and erosion are modified by new values at the end of each time step. The mass and momentum conservation were strictly followed during the simulation. Therefore, the prediction of floodplain evolutions by the integrated simulation model, proposed in this study, can be adequately and accurately given if the real condition of an floodplain can be obtained in detail.

  3. Nanoparticles laden in situ gel for sustained ocular drug delivery

    Directory of Open Access Journals (Sweden)

    Himanshu Gupta


    Full Text Available Proper availability of drug on to corneal surface is a challenging task. However, due to ocular physiological barriers, conventional eye drops display poor ocular bioavailability of drugs (< 1%. To improve precorneal residence time and ocular penetration, earlier our group developed and evaluated in situ gel and nanoparticles for ocular delivery. In interest to evaluate the combined effect of in situ gel and nanoparticles on ocular retention, we combined them. We are the first to term this combination as "nanoparticle laden in situ gel", that is, poly lactic co glycolic acid nanoparticle incorporated in chitosan in situ gel for sparfloxacin ophthalmic delivery. The formulation was tested for various physicochemical properties. It showed gelation pH near pH 7.2. The observation of acquired gamma camera images showed good retention over the entire precorneal area for sparfloxacin nanoparticle laden in situ gel (SNG as compared to marketed formulation. SNG formulation cleared at a very slow rate and remained at corneal surface for longer duration as no radioactivity was observed in systemic circulation. The developed formulation was found to be better in combination and can go up to the clinical evaluation and application.

  4. Culture-Laden Imports: International Market Entry and Cultural Taboos

    Directory of Open Access Journals (Sweden)

    Brice William David


    Full Text Available This empirical study investigates American market responses to a Spanish product that is strongly culture-laden and may violate cultural taboos. Surveys were conducted in two contrasting US universities in Arkansas and California. Contrasting student majors were also chosen: Art and Business. The product is a life-sized baby doll, designed to be breast-fed rather than bottle-fed, which highlights the benefits and normality of breast-feeding babies. Although this product is popular in its original European market, US media accounts suggested strongly negative morality-based American reactions. This study found a strong overall non-acceptance of this product in all groups, but with significant differences between groups. Results quantify the market reaction and illuminate its cultural basis by comparing responses between two culturally different regions, two contrasting college majors, different genders, and different ethnicities. In doing so, this study helps to break new ground in the international marketing of culture-laden products.

  5. A superstructure-based electrochemical assay for signal-amplified detection of DNA methyltransferase activity. (United States)

    Zhang, Hui; Yang, Yin; Dong, Huilei; Cai, Chenxin


    DNA methyltransferase (MTase) activity is highly correlated with the occurrence and development of cancer. This work reports a superstructure-based electrochemical assay for signal-amplified detection of DNA MTase activity using M.SssI as an example. First, low-density coverage of DNA duplexes on the surface of the gold electrode was achieved by immobilized mercaptohexanol, followed by immobilization of DNA duplexes. The duplex can be cleaved by BstUI endonuclease in the absence of DNA superstructures. However, the cleavage is blocked after the DNA is methylated by M.SssI. The DNA superstructures are formed with the addition of helper DNA. By using an electroactive complex, RuHex, which can bind to DNA double strands, the activity of M.SssI can be quantitatively detected by differential pulse voltammetry. Due to the high site-specific cleavage by BstUI and signal amplification by the DNA superstructure, the biosensor can achieve ultrasensitive detection of DNA MTase activity down to 0.025U/mL. The method can be used for evaluation and screening of the inhibitors of MTase, and thus has potential in the discovery of methylation-related anticancer drugs.

  6. Ab initio study of long-period superstructures in close-packed A3B compounds

    DEFF Research Database (Denmark)

    Rosengaard, N. M.; Skriver, Hans Lomholt


    We have performed ab initio calculations of the stability of one-dimensional long-period superstructures in Cu3Pd, Cu3Al, and Ag3Mg by means of an interface Green's function technique based on the linear-muffin-tin-orbitals method within the tight-binding and atomic-sphere approximations. The ene...

  7. Optical scan analysis to detect minor misfit on implant-supported superstructures

    NARCIS (Netherlands)

    Tahmaseb, A.; Mercelis, P.; de Clerck, R.; Wismeijer, D.


    PURPOSE: Despite the development of novel and more precise fabrication methods, absolute passive fit of implant-supported superstructures has yet to be consistently achieved. In the past, several laboratory techniques have been described to analyze fit. The purpose of this study was to assess two me

  8. Particle tracking modeling of sediment-laden jets (United States)

    Chan, S. N.; Lee, J. H. W.


    This paper presents a general model to predict the particulate transport and deposition from a sediment-laden horizontal momentum jet. A three-dimensional (3-D) stochastic particle tracking model is developed based on the governing equation of particle motion. The turbulent velocity fluctuations are modelled by a Lagrangian velocity autocorrelation function that captures the trapping of sediment particles in turbulent eddies, which result in the reduction of settling velocity. Using classical solutions of mean jet velocity, and turbulent fluctuation and dissipation rate profiles derived from computational fluid dynamics calculations of a pure jet, the equation of motion is solved numerically to track the particle movement in the jet flow field. The 3-D particle tracking model predictions of sediment deposition and concentration profiles are in excellent agreement with measured data. The computationally demanding Basset history force is shown to be negligible in the prediction of bottom deposition profiles.

  9. Turbulence-radiation interactions in a particle-laden flow (United States)

    Frankel, Ari; Pouransari, Hadi; Iaccarino, Gianluca; Mani, Ali


    Turbulent fluctuations in a radiatively participating medium can significantly alter the mean heat transfer characteristics in a manner that current RANS models cannot accurately capture. While turbulence-radiation interaction has been studied extensively in traditional combustion systems, such interactions have not yet been studied in the context of particle-laden flows. This work is motivated by applications in particle-based solar receivers in which external radiation is primarily absorbed by a dispersed phase and conductively exchanged with the carrier fluid. Direct numerical simulations of turbulence with Lagrangian particles subject to a collimated radiation source are performed with a flux-limited diffusion approximation to radiative transfer. The dependence of the turbulence-radiation interaction statistics on the particle Stokes number will be demonstrated. Supported by PSAAP II.

  10. Particle-laden flow from geophysical to Kolmogorov scales

    CERN Document Server

    Clercx, Herman; Uijttewaal, Wim


    The dispersion of particles in a flow is of central importance in various geophysical and environmental problems. The spreading of aerosols and soot in the air, the growth and dispersion of plankton blooms in seas and oceans, or the transport of sediment in rivers, estuaries and coastal regions are striking examples. These problems are characterized by strong nonlinear coupling between several dynamical mechanisms. As a result, processes on widely different length and time scales are simultaneously of importance. The multiscale nature of this challenging field motivated the EUROMECH colloquium on particle-laden flow that was held at the University of Twente in 2006. This book contains a selection of the papers that were presented.

  11. Direct Fabrication of Free-Standing MOF Superstructures with Desired Shapes by Micro-Confined Interfacial Synthesis. (United States)

    Kim, Jin-Oh; Min, Kyoung-Ik; Noh, Hyunwoo; Kim, Dong-Hwi; Park, Soo-Young; Kim, Dong-Pyo


    Recently, metal-organic frameworks (MOFs) with multifunctional pore chemistry have been intensively investigated for positioning the desired morphology at specific locations onto substrates for manufacturing devices. Herein, we develop a micro-confined interfacial synthesis (MIS) approach for fabrication of a variety of free-standing MOF superstructures with desired shapes. This approach for engineering MOFs provides three key features: 1) in situ synthesis of various free-standing MOF superstructures with controlled compositions, shape, and thickness using a mold membrane; 2) adding magnetic functionality into MOF superstructures by loading with Fe3 O4 nanoparticles; 3) transferring the synthesized MOF superstructural array on to flat or curved surface of various substrates. The MIS route with versatile potential opens the door for a number of new perspectives in various applications.

  12. Detailed characteristics of drop-laden mixing layers: LES predictions compared to DNS (United States)

    Okong'o, N.; Leboissetier, A.; Bellan, J.


    Results have been compared from Direct Numerical Simulation (DNS) and Large Eddy Simulation (LES) of a temporal mixing layer laden with evaporating drops, to assess the ability of LES to reproduce detailed characteristics of DNS.

  13. Vibrational properties of the Pt(111)- p(2 × 2)-K surface superstructure (United States)

    Rusina, G. G.; Eremeev, S. V.; Borisova, S. D.; Chulkov, E. V.


    The vibrational spectra of the Pt(111)- p(2 × 2)-K ordered surface superstructure formed on the platinum surface upon adsorption of 0.25 potassium monolayer are calculated using the interatomic interaction potentials obtained within the tight-binding approximation. The surface relaxation, the dispersion of surface phonons, the local density of surface vibrational states, and the polarization of vibrational modes of adatoms and substrate atoms are discussed. The theoretical results are in good agreement with the recently obtained experimental data.

  14. Analysis of raft foundation design based on considering influence of superstructure stiffness

    Institute of Scientific and Technical Information of China (English)

    WANG Bin; QIU Jianhui; ZHAO Dong; YANG Xi; DAI Shuai


    The finite element method was used for analysis of raft foundation design in high-rise building. Compared with other conventional methods, this method is more adapted to the practical condition since both superstructure stiffness and soil conditions were considered in calculation. The calculation results by example show that the base reaction is more uniform and the maximum reaction decreases obviously. Accordingly, the raft foundation design is more economic without any loss of security for high-rise building.

  15. Automatic recognition of ship types from infrared images using superstructure moment invariants (United States)

    Li, Heng; Wang, Xinyu


    Automatic object recognition is an active area of interest for military and commercial applications. In this paper, a system addressing autonomous recognition of ship types in infrared images is proposed. Firstly, an approach of segmentation based on detection of salient features of the target with subsequent shadow removing is proposed, as is the base of the subsequent object recognition. Considering the differences between the shapes of various ships mainly lie in their superstructures, we then use superstructure moment functions invariant to translation, rotation and scale differences in input patterns and develop a robust algorithm of obtaining ship superstructure. Subsequently a back-propagation neural network is used as a classifier in the recognition stage and projection images of simulated three-dimensional ship models are used as the training sets. Our recognition model was implemented and experimentally validated using both simulated three-dimensional ship model images and real images derived from video of an AN/AAS-44V Forward Looking Infrared(FLIR) sensor.

  16. Evolution of Moiré Profiles from van der Waals Superstructures of Boron Nitride Nanosheets (United States)

    Liao, Yunlong; Cao, Wei; Connell, John W.; Chen, Zhongfang; Lin, Yi


    Two-dimensional (2D) van der Waals (vdW) superstructures, or vdW solids, are formed by the precise restacking of 2D nanosheet lattices, which can lead to unique physical and electronic properties that are not available in the parent nanosheets. Moiré patterns formed by the crystalline mismatch between adjacent nanosheets are the most direct features for vdW superstructures under microscopic imaging. In this article, transmission electron microscopy (TEM) observation of hexagonal Moiré patterns with unusually large micrometer-sized lateral areas (up to ~1 μm2) and periodicities (up to ~50 nm) from restacking of liquid exfoliated hexagonal boron nitride nanosheets (BNNSs) is reported. This observation was attributed to the long range crystallinity and the contaminant-free surfaces of these chemically inert nanosheets. Parallel-line-like Moiré fringes with similarly large periodicities were also observed. The simulations and experiments unambiguously revealed that the hexagonal patterns and the parallel fringes originated from the same rotationally mismatched vdW stacking of BNNSs and can be inter-converted by simply tilting the TEM specimen following designated directions. This finding may pave the way for further structural decoding of other 2D vdW superstructure systems with more complex Moiré images.

  17. Z-contrast imaging and ab initio study on "d" superstructure in sedimentary dolomite

    CERN Document Server

    Shen, Zhizhang; Szlufarska, Izabela; Brown, Philip E; Xu, Huifang


    Nano-precipitates with tripled periodicity along the c-axis are observed in a Ca-rich dolomite sample from Proterozoic carbonate rocks with "molar tooth" structure. This observation is consistent with previous description of d reflections. High-angle annular dark-field STEM imaging (or Z-contrast imaging) that avoids dynamic diffraction as seen in electron diffraction and high-resolution TEM imaging modes, confirms that d reflections correspond to nanoscale precipitates aligned parallel to (001) of the host dolomite. The lamellae precipitates have a cation ordering sequence of Ca-Ca-Mg-Ca-Ca- Mg along the c direction resulting in a chemical composition of Ca0.67Mg0.33CO3. This superstructure is attributed to the extra or d reflections, thus is referred to as the d superstructure in this study. The structure can be simply described as interstratified calcite/dolomite. The crystal structure of the d superstructure calculated from density functional theory (DFT) has a space group of P31c and has a and c unit-cel...

  18. Superstructure formation and variation in Ni-GDC cermet anodes in SOFC. (United States)

    Li, Zhi-Peng; Mori, Toshiyuki; Auchterlonie, Graeme John; Zou, Jin; Drennan, John


    The microstructures and spatial distributions of constituent elements at the anode in solid oxide fuel cells (SOFCs) have been characterized by analytical transmission electron microscopy (TEM). High resolution TEM observations demonstrate two different types of superstructure formation in grain interiors and at grain boundaries. Energy-filtered TEM elemental imaging qualitatively reveals that mixture zones exist at metal-ceramic grain boundaries, which is also quantitatively verified by STEM energy dispersive X-ray spectroscopy. It was apparent that both metallic Ni and the rare-earth elements Ce/Gd in gadolinium-doped ceria can diffuse into each other with equal diffusion lengths (about 100 nm). This will lead to the existence of mutual diffusion zones at grain boundaries, accompanied by a change in the valence state of the diffusing ions, as identified by electron energy-loss spectroscopy (EELS). Such mutual diffusion is believed to be the dominant factor that gives rise to superstructure formation at grain boundaries, while a different superstructure is formed at grain interiors, as a consequence solely of the reduction of Ce(4+) to Ce(3+) during H(2) treatment. This work will enhance the fundamental understanding of microstructural evolution at the anode, correlating with advancements in sample preparation in order to improve the performance of SOFC anodes.

  19. Silver-colloid-nucleated cytochrome c superstructures encapsulated in silica nanoarchitectures. (United States)

    Wallace, Jean Marie; Dening, Brett M; Eden, Kristin B; Stroud, Rhonda M; Long, Jeffrey W; Rolison, Debra R


    We recently discovered that self-organized superstructures of the heme protein cytochrome c (cyt. c) are nucleated in buffer by gold nanoparticles. The protein molecules within the superstructure survive both silica sol-gel encapsulation and drying from supercritical carbon dioxide to form air-filled biocomposite aerogels that exhibit gas-phase binding activity for nitric oxide. In this investigation, we report that viable proteins are present in biocomposite aerogels when the nucleating metal nanoparticle is silver rather than gold. Silver colloids were synthesized via reduction of an aqueous solution of Ag+ using either citrate or borohydride reductants. As determined by transmission electron microscopy and UV-visible absorption spectroscopy, the silver nanoparticles vary in size and shape depending on the synthetic route, which affects the fraction of cyt. c that survives the processing necessary to form a biocomposite aerogel. Silver colloids synthesized via the citrate preparation are polydisperse, with sizes ranging from 1 to 100 nm, and lead to low cyt. c viability in the dried bioaerogels (approximately 15%). Protein superstructures nucleated at approximately 10-nm Ag colloids prepared via the borohydride route, including citrate stabilization of the borohydride-reduced metal, retain significant protein viability within the bioaerogels (approximately 45%).

  20. Hierarchical Self-Assembly of Cu7Te5 Nanorods into Superstructures with Enhanced SERS Performance. (United States)

    Zheng, Jiaojiao; Dai, Baosong; Liu, Jia; Liu, Jialong; Ji, Muwei; Liu, Jiajia; Zhou, Yuanmin; Xu, Meng; Zhang, Jiatao


    This paper reports a strategy to get self-assembly of Cu7Te5 nanorods into hierarchical superstructures: the side-by-side self-assembly of nanorods into microscale one-dimensional (1D) nanowires (primary structure), the side-by-side alignments of the 1D nanowires into two-dimensional (2D) nanowire bundles (secondary structure), and the further rolling up of the 2D bundles into three-dimensional (3D) microtubes (tertiary structure). It was found that the oleylamine (OLA)/n-dodecanethiol (DDT) mixture as a binary capping agent was key to produce Cu7Te5 nanorods in the quantum size regime with high monodispersity, and this was a prerequisite for their hierarchical self-assembly based on elaborate control of the solvent evaporation process. The obtained Cu7Te5 microtube superstructures were used as SERS substrate and showed much stronger SERS enhancement than the as-prepared Cu7Te5 nanorods before assembly. This was probably ascribed to the remarkably enhanced local electromagnetic field arising from the plasmon coupling of Cu7Te5 nanorods in the well-assembled superstructures.

  1. The emergence of superstructural order in insulin amyloid fibrils upon multiple rounds of self-seeding (United States)

    Surmacz-Chwedoruk, Weronika; Babenko, Viktoria; Dec, Robert; Szymczak, Piotr; Dzwolak, Wojciech


    Typically, elongation of an amyloid fibril entails passing conformational details of the mother seed to daughter generations of fibrils with high fidelity. There are, however, several factors that can potentially prevent such transgenerational structural imprinting from perpetuating, for example heterogeneity of mother seeds or so-called conformational switching. Here, we examine phenotypic persistence of bovine insulin amyloid ([BI]) upon multiple rounds of self-seeding under quiescent conditions. According to infrared spectroscopy, with the following passages of homologous seeding, daughter fibrils gradually depart from the mother seed’s spectral characteristics. We note that this transgenerational structural drift in [BI] amyloid leads toward fibrils with infrared, chiroptical, and morphological traits similar to those of the superstructural variant of fibrils which normally forms upon strong agitation of insulin solutions. However, in contrast to agitation-induced insulin amyloid, the superstructural assemblies of daughter fibrils isolated through self-seeding are sonication-resistant. Our results suggest that formation of single amyloid fibrils is not a dead-end of the amyloidogenic self-assembly. Instead, the process appears to continue toward the self-assembly of higher-order structures although on longer time-scales. From this perspective, the fast agitation-induced aggregation of insulin appears to be a shortcut to amyloid superstructures whose formation under quiescent conditions is slow.

  2. Nanoparticles laden in situ gelling system for ocular drug targeting

    Directory of Open Access Journals (Sweden)

    Divya Kumar


    Full Text Available Designing an ophthalmic drug delivery system is one of the most difficult challenges for the researchers. The anatomy and physiology of eye create barriers like blinking which leads to the poor retention time and penetration of drug moiety. Some conventional ocular drug delivery systems show shortcomings such as enhanced pre-corneal elimination, high variability in efficiency, and blurred vision. To overcome these problems, several novel drug delivery systems such as liposomes, nanoparticles, hydrogels, and in situ gels have been developed. In situ-forming hydrogels are liquid upon instillation and undergo phase transition in the ocular cul-de-sac to form viscoelastic gel and this provides a response to environmental changes. In the past few years, an impressive number of novel temperature, pH, and ion-induced in situ-forming systems have been reported for sustain ophthalmic drug delivery. Each system has its own advantages and drawbacks. Thus, a combination of two drug delivery systems, i.e., nanoparticles and in situ gel, has been developed which is known as nanoparticle laden in situ gel. This review describes every aspects of this novel formulation, which present the readers an exhaustive detail and might contribute to research and development.

  3. Modelling of particle-laden flow inside nanomaterials (United States)

    Chan, Yue; Wylie, Jonathan J.; Xia, Liang; Ren, Yong; Chen, Yung-Tsang


    In this paper, we demonstrate the usage of the Nernst-Planck equation in conjunction with mean-field theory to investigate particle-laden flow inside nanomaterials. Most theoretical studies in molecular encapsulation at the nanoscale do not take into account any macroscopic flow fields that are crucial in squeezing molecules into nanostructures. Here, a multi-scale idea is used to address this issue. The macroscopic transport of gas is described by the Nernst-Planck equation, whereas molecular interactions between gases and between the gas and the host material are described using a combination of molecular dynamics simulation and mean-field theory. In particular, we investigate flow-driven hydrogen storage inside doubly layered graphene sheets and graphene-oxide frameworks (GOFs). At room temperature and with slow velocity fields, we find that a single molecular layer is formed almost instantaneously on the inner surface of the graphene sheets, while molecular ligands between GOFs induce multi-layers. For higher velocities, multi-layers are also formed between graphene. For even larger velocities, the cavity of graphene is filled entirely with hydrogen, whereas for GOFs there exist two voids inside each periodic unit. The flow-driven hydrogen storage inside GOFs with various ligand densities is also investigated.

  4. Finding Emotional-Laden Resources on the World Wide Web

    Directory of Open Access Journals (Sweden)

    Diane Rasmussen Neal


    Full Text Available Some content in multimedia resources can depict or evoke certain emotions in users. The aim of Emotional Information Retrieval (EmIR and of our research is to identify knowledge about emotional-laden documents and to use these findings in a new kind of World Wide Web information service that allows users to search and browse by emotion. Our prototype, called Media EMOtion SEarch (MEMOSE, is largely based on the results of research regarding emotive music pieces, images and videos. In order to index both evoked and depicted emotions in these three media types and to make them searchable, we work with a controlled vocabulary, slide controls to adjust the emotions’ intensities, and broad folksonomies to identify and separate the correct resource-specific emotions. This separation of so-called power tags is based on a tag distribution which follows either an inverse power law (only one emotion was recognized or an inverse-logistical shape (two or three emotions were recognized. Both distributions are well known in information science. MEMOSE consists of a tool for tagging basic emotions with the help of slide controls, a processing device to separate power tags, a retrieval component consisting of a search interface (for any topic in combination with one or more emotions and a results screen. The latter shows two separately ranked lists of items for each media type (depicted and felt emotions, displaying thumbnails of resources, ranked by the mean values of intensity. In the evaluation of the MEMOSE prototype, study participants described our EmIR system as an enjoyable Web 2.0 service.

  5. Evaporation of Sessile Droplets Laden with Particles and Insoluble Surfactants. (United States)

    Karapetsas, George; Chandra Sahu, Kirti; Matar, Omar K


    We consider the flow dynamics of a thin evaporating droplet in the presence of an insoluble surfactant and noninteracting particles in the bulk. On the basis of lubrication theory, we derive a set of evolution equations for the film height, the interfacial surfactant, and bulk particle concentrations, taking into account the dependence of liquid viscosity on the local particle concentration. An important ingredient of our model is that it takes into account the fact that the surfactant adsorbed at the interface hinders evaporation. We perform a parametric study to investigate how the presence of surfactants affects the evaporation process as well as the flow dynamics with and without the presence of particles in the bulk. Our numerical calculations show that the droplet lifetime is affected significantly by the balance between the ability of the surfactant to enhance spreading, suppressing the effect of thermal Marangoni stresses-induced motion, and to hinder the evaporation flux through the reduction of the effective interfacial area of evaporation, which tend to accelerate and decelerate the evaporation process, respectively. For particle-laden droplets and in the case of dilute solutions, the droplet lifetime is found to be weakly dependent on the initial particle concentration. We also show that the particle deposition patterns are influenced strongly by the direct effect of the surfactant on the evaporative flux; in certain cases, the "coffee-stain" effect is enhanced significantly. A discussion of the delicate interplay between the effects of capillary pressure and solutal and thermal Marangoni stresses, which drive the liquid flow inside of the evaporating droplet giving rise to the observed results, is provided herein.

  6. An experimental investigation of the dynamics of submarine leveed channel initiation as sediment-laden density currents experience sudden unconfinement

    Energy Technology Data Exchange (ETDEWEB)

    Rowland, Joel C [Los Alamos National Laboratory; Hilley, George E [STANFORD UNIV; Fildani, Andrea [CHEVRON ETC


    Leveed submarine channels play a critical role in the transfer of sediment from the upper continental slopes to interslope basins and ultimately deepwater settings. Despite a reasonable understanding of how these channels grow once established, how such channels initiate on previously unchannelized portions of the seafloor remains poorly understood. We conducted a series of experiments that elucidate the influence of excess density relative to flow velocity on the dynamics of, and depositional morphologies arising from, density currents undergoing sudden unconfinement across a sloped bed. Experimental currents transported only suspended sediment across a non-erodible substrate. Under flow conditions ranging from supercritical to subcritical (bulk Richardson numbers of 0.02 to 1.2) our experiments failed to produce deposits resembling or exhibiting the potential to evolve into self-formed leveed channels. In the absence of excess density, a submerged sediment-laden flow produced sharp crested lateral deposits bounding the margins of the flow for approximately a distance of two outlet widths down basin. These lateral deposits terminated in a centerline deposit that greatly exceeded marginal deposits in thickness. As excess density increased relative to the outlet velocity, the rate of lateral spreading of the flow increased relative to the downstream propagation of the density current, transitioning from a narrow flow aligned with the channel outlet to a broad radially expanding flow. Coincident with these changes in flow dynamics, the bounding lateral deposits extended for shorter distances, had lower, more poorly defined crests that were increasingly wider in separation than the initial outlet, and progressively became more oblong rather than linear. Based on our results, we conclude that leveed channels cannot initiate from sediment-laden density currents under strictly depositional conditions. Partial confinement of these currents appears to be necessary to

  7. Acquisition of the linearization process in text composition in third to ninth graders: effects of textual superstructure and macrostructural organization. (United States)

    Favart, Monik; Coirier, Pierre


    Two complementary experiments analyzed the acquisition of text content linearization in writing, in French-speaking participants from third to ninth grades. In both experiments, a scrambled text paradigm was used: eleven ideas presented in random order had to be rearranged coherently so as to compose a text. Linearization was analyzed on the basis of the conceptual ordering of ideas and writing fluency. The first experiment focused on the effect of superstructural facilitation (in decreasing order: 1--instructional, 2--narrative, 3--argumentative), while the second experiment studied the effect of prewriting conditions: 1-scrambled presentation, 2--macrostructural facilitation, 3--ideas given in optimal order (control condition). As expected, scores in conceptual ordering and writing fluency improved through the grade levels. Students were most successful with respect to conceptual ordering in the instructional superstructure, followed by the narrative and finally the argumentative superstructures. The prewriting assignment also had the expected effect (control better than macrostructural presentation which, in turn, was better than the random order) but only with the argumentative superstructure. Contrary to conceptual ordering, writing fluency was not affected by the type of superstructure, although we did record an effect of the prewriting condition. The results are discussed in light of Bereiter and Scardamalia's knowledge transforming strategy (1987) taking into account cognitive development and French language curriculum.

  8. A spray-drying strategy for synthesis of nanoscale metal-organic frameworks and their assembly into hollow superstructures. (United States)

    Carné-Sánchez, Arnau; Imaz, Inhar; Cano-Sarabia, Mary; Maspoch, Daniel


    Metal-organic frameworks (MOFs) are among the most attractive porous materials known today. Their miniaturization to the nanoscale--into nanoMOFs--is expected to serve myriad applications from drug delivery to membranes, to open up novel avenues to more traditional storage and catalysis applications, and to enable the creation of sophisticated superstructures. Here, we report the use of spray-drying as a versatile methodology to assemble nanoMOFs, yielding spherical hollow superstructures with diameters smaller than 5 µm. This strategy conceptually mimics the emulsions used by chemists to confine the synthesis of materials, but does not require secondary immiscible solvents or surfactants. We demonstrate that the resulting spherical, hollow superstructures can be processed into stable colloids, whose disassembly by sonication affords discrete, homogeneous nanoMOFs. This spray-drying strategy enables the construction of multicomponent MOF superstructures, and the encapsulation of guest species within these superstructures. We anticipate that this will provide new routes to capsules, reactors and composite materials.

  9. System design optimization for stand-alone photovoltaic systems sizing by using superstructure model (United States)

    Azau, M. A. M.; Jaafar, S.; Samsudin, K.


    Although the photovoltaic (PV) systems have been increasingly installed as an alternative and renewable green power generation, the initial set up cost, maintenance cost and equipment mismatch are some of the key issues that slows down the installation in small household. This paper presents the design optimization of stand-alone photovoltaic systems using superstructure model where all possible types of technology of the equipment are captured and life cycle cost analysis is formulated as a mixed integer programming (MIP). A model for investment planning of power generation and long-term decision model are developed in order to help the system engineer to build a cost effective system.

  10. Incommensurate superstructure in heavily doped fullerene layer on Bi/Si(111) surface (United States)

    Gruznev, D. V.; Bondarenko, L. V.; Tupchaya, A. Y.; Matetskiy, A. V.; Zotov, A. V.; Saranin, A. A.


    Cs adsorption onto the C60-covered Si(111)-β- √{ 3 } × √{ 3 } -Bi reconstruction has been studied by means of scanning tunneling microscopy and photoelectron spectroscopy. Unexpected increase in apparent size of every second C60 molecule has been detected, hereupon the close packed molecular array almost doubles its periodicity. The change affects only the fullerenes that are in direct contact with the metal-induced reconstruction and takes no place already in the second layer. Photoelectron studies have revealed that this incommensurate "2 × 2" superstructure of a heavily doped C60 monolayer remains in an insulating state regardless of doping level.

  11. Models of ash-laden intrusions in a stratified atmosphere (United States)

    Hogg, Andrew; Johnson, Chris; Sparks, Steve; Huppert, Herbert; Woodhouse, Mark; Phillips, Jeremy


    Recent volcanic eruptions and the associated dispersion of ash through the atmosphere have led to widespread closures of airspace, for example the 2010 eruption of Eyjafjallajokull and 2011 eruption of Puyehue-Cordón Caulle. These episodes bring into sharp focus the need to predict quantitatively the transport and deposition of fine ash and in particular, its interaction with atmospheric wind. Many models of this process are based upon capturing the physics of advection with the wind, turbulence-induced diffusion and gravitational settling. Buoyancy-induced processes, associated with the density of the ash cloud and the background stratification of the atmosphere, are neglected and it is this issue that we address in this contribution. In particular, we suggest that the buoyancy-induced motion may account for the relatively thin distal ash layers that have been observed in the atmosphere and their relatively weak cross-wind spreading. We formulate a new model for buoyancy-driven spreading in the atmosphere in which we treat the evolving ash layer as relatively shallow so that its motion is predominantly horizontal and the pressure locally hydrostatic. The motion is driven by horizontal pressure gradients along with interfacial drag between the flowing ash layer and the surrounding atmosphere. Ash-laden fluid is delivered to this intrusion from a plume source and has risen through the atmosphere to its height of neutral buoyancy. The ash particles are then transported horizontally by the intrusion and progressively settle out of it to sediment through the atmosphere and form the deposit on the ground. This model is integrated numerically and analysed asymptotically in various regimes, including scenarios in which the atmosphere is quiescent and in which there is a sustained wind. The results yield predictions for the variation of the thickness of the intrusion with distance from the source and for how the concentration of ash is reduced due to settling. They

  12. Dielectrophoresis of a surfactant-laden viscous drop (United States)

    Mandal, Shubhadeep; Bandopadhyay, Aditya; Chakraborty, Suman


    The dielectrophoresis of a surfactant-laden viscous drop in the presence of non-uniform DC electric field is investigated analytically and numerically. Considering the presence of bulk-insoluble surfactants at the drop interface, we first perform asymptotic solution for both low and high surface Péclet numbers, where the surface Péclet number signifies the strength of surface convection of surfactants as compared to the diffusion at the drop interface. Neglecting fluid inertia and interfacial charge convection effects, we obtain explicit expression for dielectrophoretic drop velocity for low and high Péclet numbers by assuming small deviation of drop shape from sphericity and small deviation of surfactant concentration from the equilibrium uniform distribution. We then depict a numerical solution, assuming spherical drop, for arbitrary values of Péclet number. Our analyses demonstrate that the asymptotic solution shows excellent agreement with the numerical solution in the limiting conditions of low and high Péclet numbers. The present analysis shows that the flow-induced redistribution of the surfactants at the drop interface generates Marangoni stress, owing to the influence of the surfactant distribution on the local interfacial tension, at the drop interface and significantly alters the drop velocity at steady state. For a perfectly conducting/dielectric drop suspended in perfectly dielectric medium, Marangoni stress always retards the dielectrophoretic velocity of the drop as compared with a surfactant-free drop. For a leaky dielectric drop suspended in another leaky dielectric medium, in the low Péclet number limit, depending on the electrical conductivity and permittivity of both the liquids, the Marangoni stress may aid or retard the dielectrophoretic velocity of the drop. The Marangoni stress also has the ability to move the drop in the opposite direction as compared with a surfactant-free drop. This non-intuitive reverse motion of the drop is

  13. Radiative and combustion properties of nanoparticle-laden liquids (United States)

    Tyagi, Himanshu

    Key processes in energy conversion systems are radiative transport and combustion. The general objective of this dissertation is to improve energy conversion efficiency by a fundamental investigation of how nanoparticle-laden liquid suspensions, generally termed nanofluids, can be used to either enhance radiative absorption in solar thermal energy systems, or to improve the combustion properties of liquid fuels. The present study theoretically investigates the feasibility of using a non-concentrating direct absorption solar collector (DAC) and compares its performance with that of a typical flat-plate collector. Here a nanofluid - a mixture of water and aluminum nanoparticles - is used as the absorbing medium. It was observed that the presence of nanoparticles increases the absorption of incident radiation by more than 9 times over that of pure water. Under similar operating conditions, the efficiency of a DAC using nanofluid as the working fluid is found to be up to 10 percent higher (on an absolute basis) than that of a flat-plate collector. This study also attempts to improve the ignition properties of diesel fuel by investigating the influence of adding aluminum and aluminum-oxide nanoparticles to diesel. As part of this study, droplet ignition experiments were carried out atop a heated hot plate over the range of 688 to 768 degrees centigrade. Different types of fuel mixtures were used; both particle size (15 nm and 50 nm) as well as the volume fraction (0, 0.1 and 0.5 percent) of nanoparticles added to diesel were varied. It was observed that the ignition probability for the fuel mixtures which contained nanoparticles was significantly higher than that of pure diesel. Finally, the concept of using solar energy for converting biomass into useful product-gases was explored. A molten salt mixture (containing nanoparticles) was used to absorb and transfer solar energy to the biomass. Under the highest amount of solar radiation (60 times the normal solar radiation

  14. Low temperature synthesis of flower-like ZnMn 2O 4 superstructures with enhanced electrochemical lithium storage (United States)

    Xiao, Lifen; Yang, Yanyan; Yin, Jia; Li, Qiao; Zhang, Lizhi

    In this communication, flower-like tetragonal ZnMn 2O 4 superstructures are synthesized by a facile low temperature solvothermal process. Characterizations show that these ZnMn 2O 4 superstructures are well crystallized and of high purity. The product exhibits an initial electrochemical capacity of 763 mAh g -1 and retains stable capacity of 626 mAh g -1 after 50 cycles. Its stable capacity is significantly higher than that of nanocrystalline ZnMn 2O 4 synthesized by a polymer-pyrolysis method. It is found that the higher capacity retention can be attributed to three-dimensional superstructural nature of the as-prepared flower-like ZnMn 2O 4 material. This study suggests that the solvothermally synthesized flower-like ZnMn 2O 4 is a promising anode material for lithium-ion batteries.


    Institute of Scientific and Technical Information of China (English)

    HUANG Xi-bin; YUAN Yin-zhong


    The wall surface of material is prone to silt abrasion by high-velocity sediment-laden flow. The silt abrasion is different form cavitation erosion. In this article, the characteristics of silt abrasion were discussed. The mechanism of silt abrasion was analyzed and the formation and development of ripple shape on wall surface of material were explained thereafter. Based on turbulence theory and test data, some formulas were derived for predicting the abrasion rate of concrete wall surface in high-velocity sediment-laden flow. The calculated results show good agreement with the experimental data.


    Institute of Scientific and Technical Information of China (English)


    Low concentration sediment-laden flow is usually involved in water conservancy, environmental protection, navigation and so on. In this article, a mathematical model for low-concentration sediment-laden flow was suggested based on the two-phase flow theory, and a solving scheme for the mathematical model in curvilinear grids was worked out. The observed data in the Zhang River in China was used for the verification of the model, and the calculated results of the water level, velocity and river bed deformation are in agreement with the observed ones.

  17. Superstructures formed by orientationally ordered tetrahedra in the bcc lattice: new diffusionless order-disorder transition in solids. (United States)

    Tamura, Ryuji


    We investigated and clarified the superstructures formed by tetrahedra in the bcc lattice within the framework of second-order transitions. Compliance with both the Landau and Lifshitz conditions was investigated for all possible superstructures and, based on this, we demonstrate that bcc crystals that contain tetrahedra at an inversion center can exhibit a variety of second-order transitions, which are regarded as a new type of diffusionless order-disorder transition with antiferroic orientational orders. Finally, we show that the transition gives rise to a new glassy state. Breaking of the local inversion symmetry may lead to a new orientational glass, which is reminiscent of spin glasses in magnetism.

  18. The Effects on the Operating Condition of a Passenger Ship Retro-fitted with a Composite Superstructure

    DEFF Research Database (Denmark)

    Karatzas, Vasileios; Hjørnet, N. K.; Kristensen, Hans Otto Holmegaard


    As sustainability and climate change have come on the politi-cal agenda, the shipping industry will have to be operating energy efficient ships. An appealing step to achieve this goal is by designing superstructures made out of Fiber Reinforced Plastics (FRP) aiming at the reduction of the ship...... the stability of the ship. In this work, the superstructure of a RoPax ferry has been redesigned using composite materials emphasizing the effects on the ship from an operational per-spective. The weight reduction has been calculated for a real-istic average operating condition quantifying the effects...

  19. Combined mass and heat exchange network synthesis based on stage-wise superstructure model☆

    Institute of Scientific and Technical Information of China (English)

    Linlin Liu; Jian Du; Fenglin Yang


    Integrating multiple systems into one has become an important trend in Process Systems Engineering research field since there is strong demand from the modern industries. In this study, a stage-wise superstructure-based method is proposed to synthesize a combined mass and heat exchange network (CM&HEN) which has two parts as the mass exchange network (MEN) and heat exchange network (HEN) involved. To express the pos-sible heat exchange requirements resulted from mass exchange operations, a so cal ed“indistinct HEN super-structure (IHS)”, which can contain the all potential matches between streams, is constructed at first. Then, a non-linear programming (NLP) mathematical model is established for the simultaneous synthesis and optimiza-tion of networks. Therein, the interaction between mass exchange and heat exchange is modeling formulated. The NLP model has later been examined using an example from literature, and the effectiveness of the proposed method has been demonstrated with the results.

  20. Comparative analysis of cogeneration power plants optimization based on stochastic method using superstructure and process simulator

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Leonardo Rodrigues de [Instituto Federal do Espirito Santo, Vitoria, ES (Brazil)], E-mail:; Donatelli, Joao Luiz Marcon [Universidade Federal do Espirito Santo (UFES), Vitoria, ES (Brazil)], E-mail:; Silva, Edmar Alino da Cruz [Instituto Tecnologico de Aeronautica (ITA/CTA), Sao Jose dos Campos, SP (Brazil); Azevedo, Joao Luiz F. [Instituto de Aeronautica e Espaco (CTA/IAE/ALA), Sao Jose dos Campos, SP (Brazil)


    Thermal systems are essential in facilities such as thermoelectric plants, cogeneration plants, refrigeration systems and air conditioning, among others, in which much of the energy consumed by humanity is processed. In a world with finite natural sources of fuels and growing energy demand, issues related with thermal system design, such as cost estimative, design complexity, environmental protection and optimization are becoming increasingly important. Therefore the need to understand the mechanisms that degrade energy, improve energy sources use, reduce environmental impacts and also reduce project, operation and maintenance costs. In recent years, a consistent development of procedures and techniques for computational design of thermal systems has occurred. In this context, the fundamental objective of this study is a performance comparative analysis of structural and parametric optimization of a cogeneration system using stochastic methods: genetic algorithm and simulated annealing. This research work uses a superstructure, modelled in a process simulator, IPSEpro of SimTech, in which the appropriate design case studied options are included. Accordingly, the cogeneration system optimal configuration is determined as a consequence of the optimization process, restricted within the configuration options included in the superstructure. The optimization routines are written in MsExcel Visual Basic, in order to work perfectly coupled to the simulator process. At the end of the optimization process, the system optimal configuration, given the characteristics of each specific problem, should be defined. (author)

  1. The Effect of Superstructures Connected to Implants with Different Surface Properties on the Surrounding Bone

    Directory of Open Access Journals (Sweden)

    Katsunori Koretake


    Full Text Available The objective of this study was to investigate how the connection of superstructures to implants with different surface properties affects the surrounding bone. The right and left mandibular premolars and molars of 5 dogs were extracted. After 12 weeks, a machined implant was placed mesially and an anodized implant was placed distally on one side of the edentulous jaw, with the positions reversed on the opposite side. Twelve weeks after implantation, splinted superstructures were set to the implants. At 24 weeks after implantation, the implant stability quotient (ISQ was measured, radiographs were obtained. Removal torque values were measured and histologic observation was performed. The ISQ values at 24 weeks after implantation were not significantly different between the groups. The removal torque values were significantly different between the distal anodized and distal machined implants (p < 0.05. From 12 to 24 weeks, marginal bone losses were not significantly different between the groups. Fluorescent observation of tissue samples revealed bone-remodeling activity around all of the implants. The results of this study suggest that when implants with different surface properties are connected, machined implants at the most distal sites might be a potential risk factor for implant-bone binding.

  2. Anomalous hexagonal superstructure of aluminum oxide layer grown on NiAl(110) surface (United States)

    Krukowski, Pawel; Chaunchaiyakul, Songpol; Minagawa, Yuto; Yajima, Nami; Akai-Kasaya, Megumi; Saito, Akira; Kuwahara, Yuji


    A modified method for the fabrication of a highly crystallized layer of aluminum oxide on a NiAl(110) surface is reported. The fabrication method involves the multistep selective oxidation of aluminum atoms on a NiAl(110) surface resulting from successive oxygen deposition and annealing. The surface morphology and local electronic structure of the novel aluminum oxide layer were investigated by high-resolution imaging using scanning tunneling microscopy (STM) and current imaging tunneling spectroscopy. In contrast to the standard fabrication method of aluminum oxide on a NiAl(110) surface, the proposed method produces an atomically flat surface exhibiting a hexagonal superstructure. The superstructure exhibits a slightly distorted hexagonal array of close-packed bright protrusions with a periodicity of 4.5 ± 0.2 nm. Atomically resolved STM imaging of the aluminum oxide layer reveals a hexagonal arrangement of dark contrast spots with a periodicity of 0.27 ± 0.02 nm. On the basis of the atomic structure of the fabricated layer, the formation of α-Al2O3(0001) on the NiAl(110) surface is suggested.

  3. Solving a superstructure from two—wavelength x—ray powder diffraction data—a simulation

    Institute of Scientific and Technical Information of China (English)

    陈建荣; 古元新; 等


    Two different kinds of phase ambiguities are intrinsic in two-wavelength x-ray powder diffraction from acentric crystal structures having pseudo-translation symmetry.In a test calculation we have solved the problem for the first time by two different phasing procedures developed originally in single-crystal structure analysis.They are the direct method of breaking enantiomorphous phase ambiguity in protein crystallography and that of breaking translational phase ambiguity for superstructures.An artificial structure was used in the test,which is based on atomic coordinates of the known structure,SHAS(C5H6O5N3K),with the atom K replaced by Rb.The arrangement of Rb atoms possesses a subperiodicity of t =(a+b+c)/2.Two -wavelength synchrotron x-ray powder diffraction data were simulated with λ1=0.0816nm and λ2=0.1319nm.Overlapped reflections were uniformly decomposed at the beginning and rdedcomposed afterward when the partial-structure in formation became available.The enantiomorphous phase ambiguity was resolved only for reflections with h+k+l even.Phases of reflections with h+k+l odd were derived by the direct method of solving superstructures.A fragment was then obtained.which led to the the complete structure in five cycles of Fourier iteration.

  4. Solving a superstructure from two-wavelength x-ray powder diffraction data- a simulation

    Institute of Scientific and Technical Information of China (English)

    陈建荣; 古元新; 范海福


    Two different kinds of phase ambiguities are intrinsic in two-wavelength x-ray powder diffraction from acentric crystal structures having pseudo-translation symmetry. In a test calculation we have solved the problem for the first time by two different phasing procedures developed originally in single-crystal structure analysis. They are the direct method of breaking enantiomorphous phase ambiguity in protein crystallography and that of breaking translational phase ambiguity for superstructures. An artificial structure was used in the test, which is based on atomic coordinates of the known structure, SHAS (C5H6O5N3K), with the atom K replaced by Rb. The arrangement of Rb atoms possesses a subperiodicity of t = (a + b + c)/2. Two-wavelength synchrotron x-ray powder diffraction data were simulated with λ1 =0.0816nm and λ2=0.1319nm. Overlapped reflections were uniformly decomposed at the beginning and redecomposed afterward when the partial-structure information became available. The enantiomorphous phase ambiguity was resolved only for reflections with h + k + l even. Phases of reflections with h + k + l odd were derived by the direct method of solving superstructures. A fragment was then obtained, which led to the complete structure in five cycles of Fourier iteration.

  5. Teaching About Theory-Laden Observation to Secondary Students Through Manipulated Lab Inquiry Experience (United States)

    Lau, Kwok-chi; Chan, Shi-lun


    This study seeks to develop and evaluate a modified lab inquiry approach to teaching about nature of science (NOS) to secondary students. Different from the extended, open-ended inquiry, this approach makes use of shorter lab inquiry activities in which one or several specific NOS aspects are manipulated deliberately so that students are compelled to experience and then reflect on these NOS aspects. In this study, to let students experience theory-laden observation, they were provided with different "theories" in order to bias their observations in the lab inquiry. Then, in the post-lab discussion, the teacher guided students to reflect on their own experience and explicitly taught about theory-ladenness. This study employs a quasi-experimental pretest-posttest design using the historical approach as the control group. The results show that the manipulated lab inquiry approach was much more effective than the historical approach in fostering students' theory-laden views, and it was even more effective when the two approaches were combined. Besides, the study also sought to examine the practical epistemological beliefs of students concerning theory-ladenness, but limited evidence could be found.

  6. Enhancing the biocompatibility of microfluidics-assisted fabrication of cell-laden microgels with channel geometry. (United States)

    Kim, Suntae; Oh, Jonghyun; Cha, Chaenyung


    Microfluidic flow-focusing devices (FFD) are widely used to generate monodisperse droplets and microgels with controllable size, shape and composition for various biomedical applications. However, highly inconsistent and often low viability of cells encapsulated within the microgels prepared via microfluidic FFD has been a major concern, and yet this aspect has not been systematically explored. In this study, we demonstrate that the biocompatibility of microfluidic FFD to fabricate cell-laden microgels can be significantly enhanced by controlling the channel geometry. When a single emulsion ("single") microfluidic FFD is used to fabricate cell-laden microgels, there is a significant decrease and batch-to-batch variability in the cell viability, regardless of their size and composition. It is determined that during droplet generation, some of the cells are exposed to the oil phase which is shown to have a cytotoxic effect. Therefore, a microfluidic device with a sequential ('double') flow-focusing channels is employed instead, in which a secondary aqueous phase containing cells enters the primary aqueous phase, so the cells' exposure to the oil phase is minimized by directing them to the center of droplets. This microfluidic channel geometry significantly enhances the biocompatibility of cell-laden microgels, while maintaining the benefits of a typical microfluidic process. This study therefore provides a simple and yet highly effective strategy to improve the biocompatibility of microfluidic fabrication of cell-laden microgels.


    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.


    Metal-laden wastes can be stabilized and solidified using advanced clean coal technology by-products (CCTBs)--fluid bed combustor ash and spray drier solids. These utility-generated treatment chemicals are available for purchase through brokers, and commercial applications of this process are being practiced by treaters of metal-laden hazardous waste. A complex of regulations governs this industry, and sensitivities to this complex has discouraged public documentation of treatment of metal-laden hazardous wastes with CCTBs. This report provides a comprehensive public documentation of laboratory studies that show the efficacy of the stabilization and solidification of metal-laden hazardous wastes--such as lead-contaminated soils and sandblast residues--through treatment with CCTBs. It then describes the extensive efforts that were made to obtain the permits allowing a commercial hazardous waste treater to utilize CCTBs as treatment chemicals and to install the equipment required to do so. It concludes with the effect of this lengthy process on the ability of the treatment company to realize the practical, physical outcome of this effort, leading to premature termination of the project.

  8. A posterirori study of models for large eddy simulations of drop-laden flows (United States)

    Leboissetier, A.; Okong'o, N. A.; Bellan, J.


    Large Eddy Simulation (LES) is conducted of a three-dimensional temporal mixing layer whose stream is initially laden with liquid drops which may evaporate during the simulation. The gas-phase equations are written in Eulerian frame for two perfect gas species (carrier gas and vapor emanating from the drops), while the liquid-phase equations are written in a Lagrangian frame.

  9. Investigator Bias and Theory-Ladenness in Cross-Cultural Research: Insights from Wittgenstein (United States)

    Tan, Charlene


    A relatively under-explored topic in the current literature on and methods for research in the field of comparative and international education is the problem of investigator bias in cross-cultural research. This article discusses the nature of and an approach to address investigator bias in research that originates from the theory-ladenness of…

  10. Prediction of dynamic and mixing characteristics of drop-laden mixing layers using DNS and LES (United States)

    Okong'o, N.; Leboissetier, A.; Bellan, J.


    Direct Numerical Simulation (DNS) and Large Eddy Simulation (LES) have been conducted of a temporal mixing layer laden with evaporating drops, in order to assess the ability of LES to reproduce dynamic and mixing aspects of the DNS which affect combustion, independently of combustion models.

  11. Direct-write bioprinting of cell-laden methacrylated gelatin hydrogels. (United States)

    Bertassoni, Luiz E; Cardoso, Juliana C; Manoharan, Vijayan; Cristino, Ana L; Bhise, Nupura S; Araujo, Wesleyan A; Zorlutuna, Pinar; Vrana, Nihal E; Ghaemmaghami, Amir M; Dokmeci, Mehmet R; Khademhosseini, Ali


    Fabrication of three dimensional (3D) organoids with controlled microarchitectures has been shown to enhance tissue functionality. Bioprinting can be used to precisely position cells and cell-laden materials to generate controlled tissue architecture. Therefore, it represents an exciting alternative for organ fabrication. Despite the rapid progress in the field, the development of printing processes that can be used to fabricate macroscale tissue constructs from ECM-derived hydrogels has remained a challenge. Here we report a strategy for bioprinting of photolabile cell-laden methacrylated gelatin (GelMA) hydrogels. We bioprinted cell-laden GelMA at concentrations ranging from 7 to 15% with varying cell densities and found a direct correlation between printability and the hydrogel mechanical properties. Furthermore, encapsulated HepG2 cells preserved cell viability for at least eight days following the bioprinting process. In summary, this work presents a strategy for direct-write bioprinting of a cell-laden photolabile ECM-derived hydrogel, which may find widespread application for tissue engineering, organ printing and the development of 3D drug discovery platforms.

  12. The line shape of the Ortho-II superstructure reflection in YBa2Cu3O6.5

    DEFF Research Database (Denmark)

    Schleger, P.; Hadfield, R.; Casalta, H.;


    Neutron and synchrotron x-ray measurements of the Ortho-II superstructure reflections on a high quality single crystal of YBa2Cu3O6.5 revealed that the intrinsic line shape is a Lorentzian to the power 5/2. It is argued that such a line shape implies late-stage domain coarsening of a quenched...

  13. Nanoscale superstructures assembled by polymerase chain reaction (PCR): programmable construction, structural diversity, and emerging applications. (United States)

    Kuang, Hua; Ma, Wei; Xu, Liguang; Wang, Libing; Xu, Chuanlai


    Polymerase chain reaction (PCR) is an essential tool in biotechnology laboratories and is becoming increasingly important in other areas of research. Extensive data obtained over the last 12 years has shown that the combination of PCR with nanoscale dispersions can resolve issues in the preparation DNA-based materials that include both inorganic and organic nanoscale components. Unlike conventional DNA hybridization and antibody-antigen complexes, PCR provides a new, effective assembly platform that both increases the yield of DNA-based nanomaterials and allows researchers to program and control assembly with predesigned parameters including those assisted and automated by computers. As a result, this method allows researchers to optimize to the combinatorial selection of the DNA strands for their nanoparticle conjugates. We have developed a PCR approach for producing various nanoscale assemblies including organic motifs such as small molecules, macromolecules, and inorganic building blocks, such as nanorods (NRs), metal, semiconductor, and magnetic nanoparticles (NPs). We start with a nanoscale primer and then modify that building block using the automated steps of PCR-based assembly including initialization, denaturation, annealing, extension, final elongation, and final hold. The intermediate steps of denaturation, annealing, and extension are cyclic, and we use computer control so that the assembled superstructures reach their predetermined complexity. The structures assembled using a small number of PCR cycles show a lower polydispersity than similar discrete structures obtained by direct hybridization between the nanoscale building blocks. Using different building blocks, we assembled the following structural motifs by PCR: (1) discrete nanostructures (NP dimers, NP multimers including trimers, pyramids, tetramers or hexamers, etc.), (2) branched NP superstructures and heterochains, (3) NP satellite-like superstructures, (4) Y-shaped nanostructures and DNA

  14. Extended and quasi-continuous tuning of quantum cascade lasers using superstructure gratings and integrated heaters

    Energy Technology Data Exchange (ETDEWEB)

    Bidaux, Yves, E-mail: [Alpes Lasers SA, 1-3 Passsage Max Meuron, CH-2001 Neuchâtel (Switzerland); Institute for Quantum Electronics, ETH-Zurich, CH-8093 Zurich (Switzerland); Bismuto, Alfredo, E-mail:; Tardy, Camille; Terazzi, Romain; Gresch, Tobias; Blaser, Stéphane; Muller, Antoine [Alpes Lasers SA, 1-3 Passsage Max Meuron, CH-2001 Neuchâtel (Switzerland); Faist, Jerome [Institute for Quantum Electronics, ETH-Zurich, CH-8093 Zurich (Switzerland)


    In this work, we demonstrate broad electrical tuning of quantum cascade lasers at 9.25 μm, 8.5 μm, and 4.4 μm in continuous wave operation using Vernier-effect distributed Bragg reflectors based on superstructure gratings. Integrated micro-heaters allow to switch from one Vernier channel to the other, while predictable and mode-hop free tuning can be obtained in each channel modulating the laser current with a side mode suppression ratio as high as 30 dB. The resulting device behaves effectively as a switchable multicolour tunable source. Tuning up to 6.5% of the central wavelength is observed. To prove the importance of the developed devices for high resolution molecular spectroscopy, a N{sub 2}O absorption spectrum has been measured.

  15. Growth and Transfer of Monolithic Horizontal ZnO Nanowire Superstructures onto Flexible Substrates

    KAUST Repository

    Xu, Sheng


    A method of fabricating horizontally aligned ZnO nanowire (NW) arrays with full control over the width and length is demonstrated. A cross-sectional view of the NWs by transmission electron microscopy shows a "mushroom-like" structure. Novel monolithic multisegment superstructures are fabricated by making use of the lateral overgrowth. Ultralong horizontal ZnO NWs of an aspect ratio on the order often thousand are also demonstrated. These horizontal NWs are lifted off and transferred onto a flexible polymer substrate, which may have many great applications in horizontal ZnO NW-based nanosensor arrays, light-emitting diodes, optical gratings, integrated circuit interconnects, and high-output-power alternating-current nanogenerators. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.

  16. Application of x-ray direct methods to surface reconstructions: The solution of projected superstructures (United States)

    Torrelles, X.; Rius, J.; Boscherini, F.; Heun, S.; Mueller, B. H.; Ferrer, S.; Alvarez, J.; Miravitlles, C.


    The projections of surface reconstructions are normally solved from the interatomic vectors found in two-dimensional Patterson maps computed with the intensities of the in-plane superstructure reflections. Since for difficult reconstructions this procedure is not trivial, an alternative automated one based on the ``direct methods'' sum function [Rius, Miravitlles, and Allmann, Acta Crystallogr. A52, 634 (1996)] is shown. It has been applied successfully to the known c(4×2) reconstruction of Ge(001) and to the so-far unresolved In0.04Ga0.96As (001) p(4×2) surface reconstruction. For this last system we propose a modification of one of the models previously proposed for GaAs(001) whose characteristic feature is the presence of dimers along the fourfold direction.

  17. Synthesis of noble metal nanoparticles and their superstructures; Darstellung von Edelmetallnanopartikeln und deren Ueberstrukturen

    Energy Technology Data Exchange (ETDEWEB)

    Bigall, Nadja-Carola


    A modified synthesis procedure for citrate-stabilized gold nanoparticles in aqueous solution is transferred under application of equal concentrations to the systems silver, platinum, and palladium. The nanoparticles are analyzed by means of absorption spectroscopy and electron microscopy. Ordered superstructures of the noble-metal nanoparticles can be synthesized by infiltration of templates of block-copolymer films with aqueous nanoparticle solution. In dependence on the pre-treatment of the polymer films either two-dimensional periodical arrangements with a periodicity of less than 30 nm or fingerprint-like arrangements with a groove distance in the same order of magnitude. By removal of the polymer one- respectively two-dimensional arrangements of platinum nanowires respectively nanoparticles on a silicon waver arise.

  18. High-level organization of isochores into gigantic superstructures in the human genome (United States)

    Carpena, P.; Oliver, J. L.; Hackenberg, M.; Coronado, A. V.; Barturen, G.; Bernaola-Galván, P.


    Human DNA shows a complex structure with compositional features at many scales; the isochores—long DNA segments (~105 bp) of relatively homogeneous guanine-cytosine (G + C) content—are the largest well-documented and well-analyzed compositional structures. However, we report here on the existence of a high-level compositional organization of isochores in the human genome. By using a segmentation algorithm incorporating the long-range correlations existing in human DNA, we find that every chromosome is composed of a few huge segments (~ 107 bp) of relatively homogeneous G + C content, which become the largest compositional organization of the genome. Finally, we show evidence of the biological relevance of these superstructures, pointing to a large-scale functional organization of the human genome.

  19. Template-free synthesis of beta-In2S3 superstructures and their photocatalytic activity. (United States)

    Amutha, R; Akilandeswari, S; Ahmmad, Bashir; Muruganandham, M; Sillanpää, Mika


    In this article, we have successfully fabricated various morphological beta-Indium sulfide (In2S3) superstructures by using indium thiocyanate complex at acidic pH. All the synthesis has been performed by a template-free, hydrothermal method at 195 degrees C for 3 h. The photocatalytic activity of synthesized In2S3 have been investigated by using UV-B (lamda = 365 nm) light with Methyl Orange dye as a model pollutant. The synthesized photocatalyst was characterized by using XRD, FE-SEM, HR-TEM, DRS spectra and nitrogen adsorption analysis. The influence of indium precursors and solvents on the morphology as well as the surface properties has also been discussed. The XRD result shows that cubic phase beta-In2S3 formed under all experimental conditions. A plausible mechanism of the In2S3 microsphere formation has been discussed based on experimental observations.

  20. Crucial role of anions on arrangement of Cu₂S nanocrystal superstructures. (United States)

    Xiong, Yansong; Deng, Ke; Jia, Yuying; He, Liangcan; Chang, Lin; Zhi, Linjie; Tang, Zhiyong


    Both of the arrays of Cu₂S nanowires and the superlattices of Cu₂S nanoparticles are obtained by the solventless thermolysis of copper thiolate in the presence of laurate. For the first time, the types of anions in the reaction system, which are generally neglected in previous studies, are found to determine the structure of the final assembly products. Furthermore, experimental results shows in the presence of Cl⁻ ions, Cl⁻ ions participate in the self-assembly process and promote the formation of Cu₂S nanowire arrays. Finally, the content of Cl⁻ ions is gradually decreased with assembly reaction proceeding. Therefore, duiring the process, Cl⁻ ions play a role of 'catassembly' in the formation of Cu₂S nanocrystal superstructures.

  1. Systematic network synthesis and design: Problem formulation, superstructure generation, data management and solution

    DEFF Research Database (Denmark)

    Quaglia, Alberto; Gargalo, Carina L.; Chairakwongsa, Siwanat;


    The developments obtained in recent years in the field of mathematical programming considerably reduced the computational time and resources needed to solve large and complex Mixed Integer Non Linear Programming (MINLP) problems. Nevertheless, the application of these methods in industrial practice...... when large problems are considered. In an earlier work, we proposed a computer-aided framework for synthesis and design of process networks. In this contribution, we expand the framework by including methods and tools developed to structure, automate and simplify the mathematical formulation...... is still limited by the complexity associated with the mathematical formulation of some problems. In particular, the tasks of design space definition and representation as superstructure, as well as the data collection, validation and handling may become too complex and cumbersome to execute, especially...

  2. Chemical ordering beyond the superstructure in long-range ordered systems

    CERN Document Server

    Stana, Markus; Kozubski, Rafal; Leitner, Michael


    To describe chemical ordering in solid solutions systems Warren-Cowley short-range parameters are ordinarily used. However, they are not directly suited for application to long-range ordered systems, as they do not converge to zero for large separations. It is the aim of this paper to generalize the theory to long-range ordered systems and quantitatively discuss chemical short-range order beyond the superstructure arrangements. This is demonstrated on the example of a non-stoichiometric B2-ordered intermetallic alloy. Parameters of interatomic potentials are taken from an embedded atom method (EAM) calculations and the degree of order is simulated by the Monte Carlo method. Both on-lattice and off-lattice methods, where the latter allows individual atoms to deviate from their regular lattice sites, were used, and the resulting effects are discussed.

  3. Enhanced cellular activities of polycaprolactone/alginate-based cell-laden hierarchical scaffolds for hard tissue engineering applications. (United States)

    Lee, HyeongJin; Kim, GeunHyung


    Biomedical scaffolds have been widely investigated because they are essential for support and promotion of cell adhesion, proliferation and differentiation in three-dimensional (3D) structures. An ideal scaffold should be highly porous to enable efficient nutrient and oxygen transfer and have a 3D structure that provides optimal micro-environmental conditions for the seeded cells to obtain homogeneous growth after a long culture period. In this study, new hierarchical osteoblast-like cell (MG-63)-laden scaffolds consisting of micro-sized struts/inter-layered micro-nanofibres and cell-laden hydrogel struts with mechanically stable and biologically superior properties were introduced. Poly(ethylene oxide) (PEO) was used as a sacrificial component to generate pores within the cell-laden hydrogel struts to attain a homogeneous cell distribution and rapid cell growth in the scaffold interior. The alginate-based cell-laden struts with PEO induced fast/homogeneous cell release, in contrast to nonporous cell-laden struts. Various weight fractions (0.5, 1, 2, 3 and 3.5 wt%) of PEO were used, of which 2 wt% PEO in the cell-laden strut resulted in the most appropriate cell release and enhanced biological activities (cell proliferation and calcium deposition), compared to nonporous cell-laden struts.

  4. Hydrothermally synthesized Copper Oxide (CuO) superstructures for ammonia sensing. (United States)

    Bhuvaneshwari, S; Gopalakrishnan, N


    According to environmental protection agencies (EPA), the emission threshold of NH3 in air is 1000kg/yr which is now about 20Tg/yr. Hence, there is a rapid increase in need of NH3 sensors to timely detect and control NH3 emissions. Metal oxide nanostructures such as CuO with special features are potential candidates for NH3 sensing. In the present study, morphology controlled 3-dimensional CuO superstructures were synthesized by surfactant-free hydrothermal method for NH3 detection. In addition to conventional hydrothermal method where water as solvent, a modified approach using a mixture of water and ethylene glycol (EG) was used as solvent to control the growth process. Hierarchical superstructures namely, snowflake-like, flower-like, hollow-sphere-like and urchin-like feature with particle dimensions ranging from 0.3 to 1μm were obtained by varying water/EG ratio and reaction temperature. The synthesized nanostructures exhibited morphology dependent luminescence and gas sensing properties. The surface area and pore distribution determined by BET surface analysis also largely influenced by the presence of EG in the reaction system. The average pore diameter enhanced from 6nm to 14nm by the addition of 10ml EG as solvent. The room temperature ammonia sensing behavior of all samples was studied using an indigenous gas sensing set-up. It was found that hollow-sphere like CuO nanostructures showed a maximum sensitivity of 150% towards 600ppm ammonia with a response and recovery time of 6min. The hydrothermal synthesis strategy reported here has the advantage of producing shape controlled hierarchical materials are highly suitable for various technological applications.

  5. Prevention of Cutaneous Tissue Contracture During Removal of Craniofacial Implant Superstructures for CT and MRI Studies

    Directory of Open Access Journals (Sweden)

    Maureen Sullivan


    Full Text Available Objectives: Head and neck cancer patients who have lost facial parts following surgical intervention frequently require craniofacial implant retained facial prostheses for restoration. Many craniofacial implant patients require computed tomography and magnetic resonance imaging scans as part of their long-term follow-up care. Consequently removal of implant superstructures and peri-abutment tissue management is required for those studies. The purpose of the present paper was to describe a method for eliminating cranial imaging artifacts in patients with craniofacial implants.Material and Methods: Three patients wearing extraoral implant retained facial prostheses needing either computed tomography or magnetic resonance imaging studies were discussed. Peri-implant soft tissues contracture after removal of percutaneous craniofacial implant abutments during computed tomography and magnetic resonance imaging studies was prevented using a method proposed by authors. The procedure involves temporary removal of the supra-implant components prior to imaging and filling of the tissue openings with polyvinyl siloxane dental impression material.Results: Immediately after filling of the tissue openings with polyvinyl siloxane dental impression material patients were sent for the imaging studies, and were asked to return for removal of the silicone plugs and reconnection of all superstructure hardware after imaging procedures were complete. The silicone plugs were easily removed with a dental explorer. The percutaneous abutments were immediately replaced and screwed into the implants which were at the bone level.Conclusions: Presented herein method eliminates the source of artifacts and prevents contracture of percutaneous tissues upon removal of the implant abutments during imaging.

  6. Construction and control technology of the main bridge superstructure of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhang Hong; Luo Chenbin; Zhang Yongtao; You Xinpeng


    The Sutong Yangtze River Bridge (short as Sutong Bridge) is now the largest span cable-stayed bridge in the world. The construction of the superstructure of the middle bridge covered several stages including erection of the big block girders for the side span, assistant span and tower area, erection of standard girders and closure of the middle span. The big block girders were hoisted by a floating crane, and the standard girders were hoisted by a double crane system on the deck. The pushing assistant method was adopted for the middle span closure construction. Furthermore, key technologies and innovative methods used in the processes of girder erection and cable assemblage in all stages were expatiated systematically. An all-stage self- adaptive geometry control method was used in the construction process. By accurately controlling the unstressed dimensions and shape of all structural components in each step, and realization that the control system and the controlled system adapt to each other, the goal was to make control of the final line shape and inner force of the bridge structure achievable. Two solutions, including GPS based and total station based dynamic geometry monitoring systems, were used to resolve the measure problem under the wide-range of wind-induced vibrations in the long cantilever state. Finally, research on the wind-induced vibration of the superstructure during the construction period was executed. Buffeting response analysis to the longest single and double cantilever states were carried out. The analysis and evaluation of wind resistance safety of the main girders under the longest single cantilever state was made, and corresponding wind resistance measures were suggested. The as-built geometric error and cable force error were controlled in a required design range, and this whole technological achievement can be a benchmark for construction of other large span cable-stayed bridges in the future.

  7. Particle-laden flows forced by the disperse phase: Comparison between Lagrangian and Eulerian simulations


    Vié, Aymeric; Pouransari, Hadi; Zamansky, Rémi; Mani, Ali


    International audience; The goal of the present work is to assess the ability of Eulerian moment methods to reproduce the physics of two-way coupled particle-laden turbulent flow systems. Previous investigations have been focused on effects such as preferential concentration, and turbulence modulation, but in regimes in which turbulence is sustained by an imposed external forcing. We show that in such regimes, Eulerian methods need resolutions finer than nominal Kolmogorov scale in order to c...

  8. Numerical modelling of turbulent particle-laden sonic CO2 jets with experimental validation


    Wareing, CJ; Woolley, RM; Fairweather, M; Peakall, J; Falle, SAEG


    Under-expanded particle-laden flows resulting in velocities greater than the local speed of sound are a feature of a wide number of applications in aviatic, astronautical, and process engineering scenarios including those relating to the accidental release of high-pressure fluids from reservoirs or pipelines. Such pipelines are considered to be the most likely method for transportation of captured carbon dioxide (CO2) from power plants and other industries prior to subsequent storage in carbo...

  9. Convective Heat Transfer Enhancement Using Alternating Magnetic Fields and Particle Laden Fluid Applied to the Microscale (United States)


    oil based suspension in the miniaturized tests. 45 5. Endnotes 1 Incropera ...Microchannels,” Proceedings of ASME Thermal Engineering Summer Heat Transfer Conference. 10 Incropera , F.P., DeWitt, D.P., Bergman, T.L., and Lavine, A.S...Pogrebnyak,, 2002, “Effect of coarse particles on the heat transfer in a particle-laden turbulent boundary layer,” Int. J. Multiph. Flow, 28,12. Incropera

  10. A Tightly Coupled Particle-Fluid Model for DNA-Laden Flows in Complex Microscale Geometries

    Energy Technology Data Exchange (ETDEWEB)

    Trebotich, D; Miller, G H; Colella, P; Graves, D T; Martin, D F; Schwartz, P O


    We present a stable and convergent method for the computation of flows of DNA-laden fluids in microchannels with complex geometry. The numerical strategy combines a ball-rod model representation for polymers tightly coupled with a projection method for incompressible viscous flow. We use Cartesian grid embedded boundary methods to discretize the fluid equations in the presence of complex domain boundaries. A sample calculation is presented showing flow through a packed array microchannel in 2D.

  11. 1H NMR-Based Metabolomics Investigation of Copper-Laden Rat: A Model of Wilson’s Disease


    Jingjing Xu; Huaizhou Jiang; Jinquan Li; Kian-Kai Cheng; Jiyang Dong; Zhong Chen


    Background and Purpose Wilson’s disease (WD), also known as hepatoleticular degeneration (HLD), is a rare autosomal recessive genetic disorder of copper metabolism, which causes copper to accumulate in body tissues. In this study, rats fed with copper-laden diet are used to render the clinical manifestations of WD, and their copper toxicity-induced organ lesions are studied. To investigate metabolic behaviors of ‘decoppering’ process, penicillamine (PA) was used for treating copper-laden rats...

  12. Numerical Simulation of Low Reynolds Number Particle-Laden Gas Jet by Vortex Method (United States)

    Uchiyama, Tomomi; Yagami, Hisanori

    An air jet, which remains laminar and axisymmetric in the single-phase flow condition, is simulated numerically in the particle-laden condition. The vortex method for particle-laden gas jet proposed by the authors is employed for the simulation. An air issues with velocity U0 from a round nozzle into the air co-flowing with velocity Ua. The Reynolds number based on U0 and the nozzle diameter is 1333, the velocity ratio Ua/U0 is 0.4. Spherical glass particles with diameter 65μm are loaded at the mass loading ratio 0.025. The particle velocity at the nozzle exit is 0.68U0. The particles impose disturbances on the air and induce the three-dimensional flow, resulting in the transition from the axisymmetric flow to the non-axisymmetric one. As the particles make the air velocity fluctuation increase, the air momentum diffuses more in the radial direction, and accordingly the spread of the jet becomes larger. The abovementioned results agree well with the trend of the existing experiments. The proposed vortex method can successfully capture the flow transition caused by the particles laden on an axisymmetric air jet.

  13. Volumetric Displacement Effects In Euler-Lagrange Simulations of Sediment-Laden Oscillatory Flows (United States)

    Apte, S.; Finn, J. R.; Cihonski, A.


    An improved, three-dimensional approach for Euler-Lagrange simulation of sediment-laden oscillatory turbulent flows is developed. In this approach, the sediment particles are unresolved and subgrid similar to a discrete element model (DEM), however, the fluid volume (mass) displaced by the particle is accounted for in the conservation equations. Recent Euler-Lagrange modeling of a few microbubbles entrained in a traveling vortex ring (Cihonski et al., JFM, 2013) has shown that extension of the standard point-particle DEM method to include local volume displacement effects is critical in capturing vortex distortion effects due to microbubbles, even in a very dilute suspension. We extend this approach to investigate particle-laden oscillatory boundary layers representative of coastal sediment environments. A wall bounded, doubly periodic domain is considered laden with a layer of sediment particles in laminar as well as turbulent oscillatory boundary layers corresponding to the experiments of Keiller and Sleath (1987) and Jensen et al. (1987). Inter-particle and particle-wall collisions are modeled using a soft-sphere model which uses a nested collision grid to minimize computational effort. The effects of fluid mass displaced by the particles on the flow statistics are quantified by comparing a standard two-way coupling approach (without volume displacement effects) with volume displacement effects to show that the latter models are important for cases with low specific gravity.

  14. Drug-laden 3D biodegradable label using QR code for anti-counterfeiting of drugs. (United States)

    Fei, Jie; Liu, Ran


    Wiping out counterfeit drugs is a great task for public health care around the world. The boost of these drugs makes treatment to become potentially harmful or even lethal. In this paper, biodegradable drug-laden QR code label for anti-counterfeiting of drugs is proposed that can provide the non-fluorescence recognition and high capacity. It is fabricated by the laser cutting to achieve the roughness over different surface which causes the difference in the gray levels on the translucent material the QR code pattern, and the micro mold process to obtain the drug-laden biodegradable label. We screened biomaterials presenting the relevant conditions and further requirements of the package. The drug-laden microlabel is on the surface of the troches or the bottom of the capsule and can be read by a simple smartphone QR code reader application. Labeling the pill directly and decoding the information successfully means more convenient and simple operation with non-fluorescence and high capacity in contrast to the traditional methods.

  15. Immunization of black-tailed prairie dog against plague through consumption of vaccine-laden baits. (United States)

    Rocke, Tonie E; Smith, Susan R; Stinchcomb, Dan T; Osorio, Jorge E


    Prairie dogs (Cynomys spp.) are highly susceptible to Yersinia pestis and, along with other wild rodents, are significant reservoirs of plague for other wildlife and humans in the western United States. A recombinant raccoon poxvirus, expressing the F1 antigen of Y. pestis, was incorporated into a palatable bait and offered to three groups (n = 18, 19, and 20) of black-tailed prairie dogs (Cynomys ludovicianus) for voluntary consumption, either one, two, or three times, at roughly 3-wk intervals. A control group (n = 19) received baits containing raccoon poxvirus without the inserted antigen. Mean antibody titers to Y. pestis F1 antigen increased significantly in all groups ingesting the vaccine-laden baits, whereas the control group remained negative. Upon challenge with virulent Y. pestis, immunized groups had higher survival rates (38%) than the unimmunized control group (11%). The mean survival time of groups ingesting vaccine-laden baits either two or three times was significantly higher than that of animals ingesting vaccine-laden baits just one time and of animals in the control group. These results show that oral immunization of prairie dogs against plague provides some protection against challenge at dosages that simulate simultaneous delivery of the plague bacterium by numerous (3-10) flea bites.

  16. Observing grasping actions directed to emotion-laden objects: effects upon corticospinal excitability

    Directory of Open Access Journals (Sweden)

    Anaelli A Nogueira-Campos


    Full Text Available The motor system is recruited whenever one executes an action as well as when one observes the same action being executed by others. Although it is well established that emotion modulates the motor system, the effect of observing other individuals acting in an emotional context is particularly elusive. The main aim of this study was to investigate the effect induced by the observation of grasping directed to emotion-laden objects upon corticospinal excitability (CSE. Participants classified video-clips depicting the right-hand of an actor grasping emotion-laden objects. Twenty video-clips differing in terms of valence but balanced in arousal level were selected. Motor evoked potentials (MEPs were then recorded from the first dorsal interosseous using transcranial magnetic stimulation (TMS while the participants observed the selected emotional video-clips. During the video-clip presentation, TMS pulses were randomly applied at one of two different time points of grasping: (1 maximum grip aperture, and (2 object contact time. CSE was higher during the observation of grasping directed to unpleasant objects compared to pleasant ones. These results indicate that when someone observes an action of grasping directed to emotion-laden objects, the effect of the object valence promotes a specific modulation over the motor system.

  17. Observing Grasping Actions Directed to Emotion-Laden Objects: Effects upon Corticospinal Excitability (United States)

    Nogueira-Campos, Anaelli A.; Saunier, Ghislain; Della-Maggiore, Valeria; De Oliveira, Laura A. S.; Rodrigues, Erika C.; Vargas, Claudia D.


    The motor system is recruited whenever one executes an action as well as when one observes the same action being executed by others. Although it is well established that emotion modulates the motor system, the effect of observing other individuals acting in an emotional context is particularly elusive. The main aim of this study was to investigate the effect induced by the observation of grasping directed to emotion-laden objects upon corticospinal excitability (CSE). Participants classified video-clips depicting the right-hand of an actor grasping emotion-laden objects. Twenty video-clips differing in terms of valence but balanced in arousal level were selected. Motor evoked potentials (MEPs) were then recorded from the first dorsal interosseous using transcranial magnetic stimulation (TMS) while the participants observed the selected emotional video-clips. During the video-clip presentation, TMS pulses were randomly applied at one of two different time points of grasping: (1) maximum grip aperture, and (2) object contact time. CSE was higher during the observation of grasping directed to unpleasant objects compared to pleasant ones. These results indicate that when someone observes an action of grasping directed to emotion-laden objects, the effect of the object valence promotes a specific modulation over the motor system. PMID:27625602

  18. Human progenitor cell recruitment via SDF-1α coacervate-laden PGS vascular grafts. (United States)

    Lee, Kee-Won; Johnson, Noah R; Gao, Jin; Wang, Yadong


    Host cell recruitment is crucial for vascular graft remodeling and integration into the native blood vessel; it is especially important for cell-free strategies which rely on host remodeling. Controlled release of growth factors from vascular grafts may enhance host cell recruitment. Stromal cell-derived factor (SDF)-1α has been shown to induce host progenitor cell migration and recruitment; however, its potential in regenerative therapies is often limited due to its short half-life in vivo. This report describes a coacervate drug delivery system for enhancing progenitor cell recruitment into an elastomeric vascular graft by conferring protection of SDF-1α. Heparin and a synthetic polycation are used to form a coacervate, which is incorporated into poly(glycerol sebacate) (PGS) scaffolds. In addition to protecting SDF-1α, the coacervate facilitates uniform scaffold coating. Coacervate-laden scaffolds have high SDF-1α loading efficiency and provide sustained release under static and physiologically-relevant flow conditions with minimal initial burst release. In vitro assays showed that coacervate-laden scaffolds enhance migration and infiltration of human endothelial and mesenchymal progenitor cells by maintaining a stable SDF-1α gradient. These results suggest that SDF-1α coacervate-laden scaffolds show great promise for in situ vascular regeneration.

  19. Biofabrication of tissue constructs by 3D bioprinting of cell-laden microcarriers. (United States)

    Levato, Riccardo; Visser, Jetze; Planell, Josep A; Engel, Elisabeth; Malda, Jos; Mateos-Timoneda, Miguel A


    Bioprinting allows the fabrication of living constructs with custom-made architectures by spatially controlled deposition of multiple bioinks. This is important for the generation of tissue, such as osteochondral tissue, which displays a zonal composition in the cartilage domain supported by the underlying subchondral bone. Challenges in fabricating functional grafts of clinically relevant size include the incorporation of cues to guide specific cell differentiation and the generation of sufficient cells, which is hard to obtain with conventional cell culture techniques. A novel strategy to address these demands is to combine bioprinting with microcarrier technology. This technology allows for the extensive expansion of cells, while they form multi-cellular aggregates, and their phenotype can be controlled. In this work, living constructs were fabricated via bioprinting of cell-laden microcarriers. Mesenchymal stromal cell (MSC)-laden polylactic acid microcarriers, obtained via static culture or spinner flask expansion, were encapsulated in gelatin methacrylamide-gellan gum bioinks, and the printability of the composite material was studied. This bioprinting approach allowed for the fabrication of constructs with high cell concentration and viability. Microcarrier encapsulation improved the compressive modulus of the hydrogel constructs, facilitated cell adhesion, and supported osteogenic differentiation and bone matrix deposition by MSCs. Bilayered osteochondral models were fabricated using microcarrier-laden bioink for the bone compartment. These findings underscore the potential of this new microcarrier-based biofabrication approach for bone and osteochondral constructs.

  20. A Detection of the Integrated Sachs–Wolfe Imprint of Cosmic Superstructures Using a Matched-filter Approach (United States)

    Nadathur, Seshadri; Crittenden, Robert


    We present a new method for detection of the integrated Sachs–Wolfe (ISW) imprints of cosmic superstructures on the cosmic microwave background (CMB), based on a matched-filtering approach. The expected signal-to-noise ratio for this method is comparable to that obtained from the full cross-correlation, and unlike other stacked filtering techniques it is not subject to an a posteriori bias. We apply this method to Planck CMB data using voids and superclusters identified in the CMASS galaxy data from the Sloan Digital Sky Survey Data Release 12, and measure the ISW amplitude to be {A}{ISW}=1.64+/- 0.53 relative to the ΛCDM expectation, corresponding to a 3.1σ detection. In contrast to some previous measurements of the ISW effect of superstructures, our result is in agreement with the ΛCDM model.

  1. Analysis on the Superstructure of Russian Advertising Text%俄语广告语篇超结构分析

    Institute of Scientific and Technical Information of China (English)



    本文把俄语广告语篇视为特殊的语篇类型,以超结构图式理论为基础分析了俄语广告语篇的超结构图式及其组成范畴,并从实义切分角度描写了俄语广告语篇的优控述位和主位的主要特征。%This paper regards Russian advertising text as a special textual type, and analyses the superstructure of Russian advertising text and its component categories on the basis of the theory of superstructure. It also describes some main features of the theme domination and themes of Russian advertising text according to theory of actual division of the sentence.

  2. A detection of the integrated Sachs-Wolfe imprint of cosmic superstructures using a matched-filter approach

    CERN Document Server

    Nadathur, Seshadri


    We present a new method for detection of the integrated Sachs-Wolfe (ISW) imprints of cosmic superstructures on the cosmic microwave background, based on a matched filtering approach. The expected signal-to-noise ratio for this method is comparable to that obtained from the full cross-correlation, and unlike other stacked filtering techniques it is not subject to an a posteriori bias. We apply this method to Planck CMB data using voids and superclusters identified in the CMASS galaxy data from the Sloan Digital Sky Survey Data Release 12, and measure the ISW amplitude to be $A_\\mathrm{ISW}=1.64\\pm0.53$ relative to the $\\Lambda$CDM expectation, corresponding to a $3.1\\sigma$ detection. In contrast to some previous measurements of the ISW effect of superstructures, our result is in agreement with the $\\Lambda$CDM model.

  3. Pressure-Induced Oriented Attachment Growth of Large-Size Crystals for Constructing 3D Ordered Superstructures. (United States)

    Wang, Jun; Lian, Gang; Si, Haibin; Wang, Qilong; Cui, Deliang; Wong, Ching-Ping


    Oriented attachment (OA), a nonclassical crystal growth mechanism, provides a powerful bottom-up approach to obtain ordered superstructures, which also demonstrate exciting charge transmission characteristic. However, there is little work observably pronouncing the achievement of 3D OA growth of crystallites with large size (e.g., submicrometer crystals). Here, we report that SnO2 3D ordered superstructures can be synthesized by means of a self-limited assembly assisted by OA in a designed high-pressure solvothermal system. The size of primary building blocks is 200-250 nm, which is significantly larger than that in previous results (normally pressure plays the key role in the formation of 3D configuration and fusion of adjacent crystals. Furthermore, this high-pressure strategy can be readily expanded to additional materials. We anticipate that the welded structures will constitute an ideal system with relevance to applications in optical responses, lithium ion battery, solar cells, and chemical sensing.

  4. Understanding the formation of CuS concave superstructures with peroxidase-like activity (United States)

    He, Weiwei; Jia, Huimin; Li, Xiaoxiao; Lei, Yan; Li, Jing; Zhao, Hongxiao; Mi, Liwei; Zhang, Lizhi; Zheng, Zhi


    Copper sulfide (CuS) concave polyhedral superstructures (CPSs) have been successfully prepared in an ethanolic solution by a simple solvothermal reaction without the use of surfactants or templates. Two typical well defined, high symmetry CuS concave polyhedrons, forming a concave truncated cuboctahedron and icosahedron were prepared. The effect of the reaction time, temperature and different Cu ion and sulfur sources on the formation of CuS CPSs were investigated and a possible formation mechanism was proposed and discussed based on gas chromatography-mass spectrometry. More importantly, we found, for the first time, that the CuS CPSs exhibit intrinsic peroxidase-like activity, as they can quickly catalyze the oxidation of typical horseradish peroxidase (HRP) substrates, 3,3',5,5'-tetramethylbenzidine (TMB) and o-phenylenediamine (OPD), in the presence of hydrogen peroxide. In addition to the recent discoveries regarding peroxidase mimetics on Fe3O4 NPs and carbon nanostructures, our findings suggest a new kind of candidate for peroxidase mimics. This may open up a new application field of CuS micro-nano structures in biodetection, biocatalysis and environmental monitoring.Copper sulfide (CuS) concave polyhedral superstructures (CPSs) have been successfully prepared in an ethanolic solution by a simple solvothermal reaction without the use of surfactants or templates. Two typical well defined, high symmetry CuS concave polyhedrons, forming a concave truncated cuboctahedron and icosahedron were prepared. The effect of the reaction time, temperature and different Cu ion and sulfur sources on the formation of CuS CPSs were investigated and a possible formation mechanism was proposed and discussed based on gas chromatography-mass spectrometry. More importantly, we found, for the first time, that the CuS CPSs exhibit intrinsic peroxidase-like activity, as they can quickly catalyze the oxidation of typical horseradish peroxidase (HRP) substrates, 3

  5. "Dual-template" synthesis of one-dimensional conductive nanoparticle superstructures from coordination metal-peptide polymer crystals. (United States)

    Rubio-Martínez, Marta; Puigmartí-Luis, Josep; Imaz, Inhar; Dittrich, Petra S; Maspoch, Daniel


    Bottom-up fabrication of self-assembled structures made of nanoparticles may lead to new materials, arrays and devices with great promise for myriad applications. Here a new class of metal-peptide scaffolds is reported: coordination polymer Ag(I)-DLL belt-like crystals, which enable the dual-template synthesis of more sophisticated nanoparticle superstructures. In these biorelated scaffolds, the self-assembly and recognition capacities of peptides and the selective reduction of Ag(I) ions to Ag are simultaneously exploited to control the growth and assembly of inorganic nanoparticles: first on their surfaces, and then inside the structures themselves. The templated internal Ag nanoparticles are well confined and closely packed, conditions that favour electrical conductivity in the superstructures. It is anticipated that these Ag(I)-DLL belts could be applied to create long (>100 μm) conductive Ag@Ag nanoparticle superstructures and polymetallic, multifunctional Fe3 O4 @Ag nanoparticle composites that marry the magnetic and conductive properties of the two nanoparticle types.

  6. [Composition, physico-chemical properties and molecular superstructure of dietary fiber preparations of the cellan type]. (United States)

    Dongowski, G; Frigge, K; Zenke, I


    Dietary fiber preparations of "cellan" type were prepared from apples, white cabbage, sugar beet pulp, soy hulls and wheat bran by treatment with amylolytic and proteolytic enzymes as well as by chemical extractions. Scanning electron microscopic examinations show different morphological structures of the preparations and a high maintenance of native biomolecular superstructure. The content of pectin, protein, polysaccharide-hexoses and -pentoses and the composition of monosaccharides (also after their treatment with 4 or 8% sodium hydroxide) were determined. The cellans possess waterbinding capacities (WBC) between 25 g H2O/g and waterholding capacities between 50 g H2O/g. The WBC is related to the internal surface; it diminishes after treatment with NaOH. The interactions between the cellans and the adsorbed water were characterized by NMR-spin-lattice relaxation time T1. The molecular mobility increases as the water content grows. The T1-values of dried cellans decreased with increasing degree of moisture before drying. The supermolecular structure is comparatively disordered. Only in case of soy cellan a crystalline cellulose-I-modification could be identified by X-ray-diffraction pattern, esp. after NaOH treatment. The low degree of order of cellans was observed in the 13C-NMR spectra, too. Only the soy hull preparation resulted in a spectrum corresponding to well-ordered cellulose. The botanic source has an essential influence on the physico-chemical properties of dietary fiber preparations of cellan type.

  7. Two-Dimensional Bipyramid Plasmonic Nanoparticle Liquid Crystalline Superstructure with Four Distinct Orientational Packing Orders. (United States)

    Shi, Qianqian; Si, Kae Jye; Sikdar, Debabrata; Yap, Lim Wei; Premaratne, Malin; Cheng, Wenlong


    Anisotropic plasmonic nanoparticles have been successfully used as constituent elements for growing ordered nanoparticle arrays. However, orientational control over their spatial ordering remains challenging. Here, we report on a self-assembled two-dimensional (2D) nanoparticle liquid crystalline superstructure (NLCS) from bipyramid gold nanoparticles (BNPs), which showed four distinct orientational packing orders, corresponding to horizontal alignment (H-NLCS), circular arrangement (C-NLCS), slanted alignment (S-NLCS), and vertical alignment (V-NLCS) of constituent particle building elements. These packing orders are characteristic of the unique shape of BNPs because all four packing modes were observed for particles with various sizes. Nevertheless, only H-NLCS and V-NLCS packing orders were observed for the free-standing ordered array nanosheets formed from a drying-mediated self-assembly at the air/water interface of a sessile droplet. This is due to strong surface tension and the absence of particle-substrate interaction. In addition, we found the collective plasmonic coupling properties mainly depend on the packing type, and characteristic coupling peak locations depend on particle sizes. Interestingly, surface-enhanced Raman scattering (SERS) enhancements were heavily dependent on the orientational packing ordering. In particular, V-NLCS showed the highest Raman enhancement factor, which was about 77-fold greater than the H-NLCS and about 19-fold greater than C-NLCS. The results presented here reveal the nature and significance of orientational ordering in controlling plasmonic coupling and SERS enhancements of ordered plasmonic nanoparticle arrays.

  8. X-ray diffraction and spectroscopy of photoinduced ferroic superstructures (Conference Presentation) (United States)

    Stoica, Vladimir A.; Wen, Haidan; Zhang, Xiaoyi; Zhang, Zhan; Freeland, John W.; Martin, Lane; Ramesh, Ramamoorthy; Gopalan, Venkatraman


    Complex oxides and strongly correlated electron systems are at the forefront of science due to their exquisite potential for optical, spintronic, transducing/actuating, multiferroic, electrochemical, and superconducting property enhancements. Accordingly, at the nanoscale, engineering of complex oxide compounds is a promising route for discovery of novel quantum functionalities in a vast space of synthesis technique, calling for high-resolution control and visualization of physical properties and their structural basis. The advent of optical pulse techniques and related instrumentation advances is used to access dynamical separation of correlated orders that hide at equilibrium and also to create novel phases, not available via mainstream synthesis techniques. In this this talk, I will discuss resonant and non-resonant spectroscopic manipulation of phase transitions in nanoferroic oxides, focusing on ultrafast optical creation of artificial supercrystals in epitaxial superlattices. While table top nonlinear optical techniques are used to access the ferroic properties, synchrotron based time-resolved structural techniques, including diffraction and spectroscopy are decisive tools for revealing the nature of orderings in superstructures, their symmetries, phase quantification and spatial distribution with sub-micron resolution.

  9. Imprint of DES super-structures on the Cosmic Microwave Background

    CERN Document Server

    Kovács, A; García-Bellido, J; Nadathur, S; Crittenden, R; Gruen, D; Huterer, D; Bacon, D; DeRose, J; Dodelson, S; Gaztañaga, E; Kirk, D; Lahav, O; Miquel, R; Naidoo, K; Soergel, B; Whiteway, L; Abdalla, F B; Allam, S; Annis, J; Benoit-Lévy, A; Bertin, E; Brooks, D; Buckley-Geer, E; Rosell, A Carnero; Kind, M Carrasco; Carretero, J; Cunha, C E; D'Andrea, C B; da Costa, L N; DePoy, D L; Desai, S; Eifler, T F; Finley, D A; Flaugher, B; Fosalba, P; Frieman, J; Giannantonio, T; Goldstein, D A; Gruendl, R A; Gutierrez, G; James, D J; Kuehn, K; Kuropatkin, N; Marshall, J L; Melchior, P; Menanteau, F; Nord, B; Ogando, R; Plazas, A A; Romer, A K; Sanchez, E; Scarpine, V; Sevilla-Noarbe, I; Sobreira, F; Suchyta, E; Swanson, M; Tarle, G; Thomas, D; Walker, A R


    Small temperature anisotropies in the Cosmic Microwave Background can be sourced by density perturbations via the late-time integrated Sachs-Wolfe effect. Large voids and superclusters are excellent environments to make a localized measurement of this tiny imprint. In some cases excess signals have been reported. We probed these claims with an independent data set, using the first year data of the Dark Energy Survey in a different footprint, and using a different super-structure finding strategy. We identified 52 large voids and 102 superclusters at redshifts $0.2 < z < 0.65$. We used the Jubilee simulation to a priori evaluate the optimal ISW measurement configuration for our compensated top-hat filtering technique, and then performed a stacking measurement of the CMB temperature field based on the DES data. For optimal configurations, we detected a cumulative cold imprint of voids with $\\Delta T_{f} \\approx -5.0\\pm3.7~\\mu K$ and a hot imprint of superclusters $\\Delta T_{f} \\approx 5.1\\pm3.2~\\mu K$ ; t...

  10. Study of superstructure Ⅱ in multiferroic BiMnO3

    Institute of Scientific and Technical Information of China (English)

    Ge Bing-Hui; Li Fang-Hua; Li Xue-Ming; Wang Yu-Mei; Chi Zhen-Hua; Jin Chang-Qing


    The crystal structure of the minor phase,named superstructure Ⅱ,existing in multiferroic compound BiMnO3 has been studied by electron diffraction and high-resolution transmission electron microscopy.Domains of major and minor phases coexisting in BiMnO3 were observed in high-resolution electron microscope images.The unit cell of minor phase Was determined to be triclinic with the size 4×4×4 times as large as the distorted perovskitc subcell.The[111] and [101]projected structure maps of the minor phase have been derived from the corresponding images by means of the image processing.A possible rough three-dimensional(3D)structure model was proposed based on the 3D structural information extracted from the two projected structure maps.Since there is no inversion centre in the proposed model,the minor phase may contribute to the ferroelectric property of BiMnO3.


    Institute of Scientific and Technical Information of China (English)

    Yin-sheng Lv; Zhong-jie Ren; You-zhi Wan; Ping Xie; Rong-ben Zhang


    A well-defined m-phenylenediimino-bridged ladder polymethylsiloxane (LP) was first synthesized through a well-defined ladder superstructure (LS) acting as synthetic template, which was self-assembled by concerted interaction of hydrogen bonding and aromatic π-π stacking of the monomer (M), N,N'-bis(phenyldichlorosilyl)-m-phenylenediamine. Some key characterization data of LP and, in particular, the extremely vulnerable LS with very unstable Si--Cl and Si-N groups were given. The molecular weights (Mn) of LS and LP are 5010 and 10480, corresponding to about 15 and 46 monomer units, respectively. To monitor the real in situ status of LS in solution the XRD measurements of special freeze-drying samples were performed, demonstrating two characteristic peaks of ladder structure. Most importantly, both LP and LS display exceedingly sharp resonance absorption peaks with a half peak width (△1/2) as small as < 0.3 of MeSi(NH)O2/2 moieties in 29Si-NMR spectra. It is well-known that the higher the regularity of the ladder polysiloxane, the narrower the resonance peak of the siloxane moiety on the ladder backbone, and the smaller the half peak width △1/2. Therefore, the very small values of △1/2 for both LS and LP confirm that both LS and LP possess well-defined ladder structures.

  12. Presenting a Multi-level Superstructure Optimization Approach for Mechatronic System Design

    DEFF Research Database (Denmark)

    Pedersen, Henrik C.; Andersen, Torben Ole; Bech, Michael Møller


    Synergism and integration in the design process is what sets apart a Mechatronic System from a traditional, multidisciplinary system. However the typical design approach has been to divide the design problem into sub problems for each technology area (mechanics, electronics and control) and descr......Synergism and integration in the design process is what sets apart a Mechatronic System from a traditional, multidisciplinary system. However the typical design approach has been to divide the design problem into sub problems for each technology area (mechanics, electronics and control......) and describe the interface between the technologies, whereas the lack of well-established, systematic engineering methods to form the basic set-off in analysis and design of complete mechatronic systems has been obvious. The focus of the current paper is therefore to present an integrated design approach...... for mechatronic system design, utilizing a multi-level superstructure optimization based approach. Finally two design examples are presented and the possibilities and limitations of the approach are outlined....

  13. Surfactant-laden soft contact lenses for extended delivery of ophthalmic drugs. (United States)

    Kapoor, Yash; Thomas, Justin C; Tan, Grace; John, Vijay T; Chauhan, Anuj


    Eye drops are inefficient means of delivering ophthalmic drugs because of limited bioavailability and these can cause significant side effects due to systemic uptake of the drug. The bioavailability for ophthalmic drugs can be increased significantly by using contact lenses. This study focuses on the development of surfactant-laden poly-hydroxy ethyl methacrylate (p-HEMA) contact lenses that can release Cyclosporine A (CyA) at a controlled rate for extended periods of time. We focus on various Brij surfactants to investigate the effects of chain length and the presence of an unsaturated group on the drug release dynamics and partitioning inside the surfactant domains inside the gel. The gels were imaged by cryogenic scanning electron microscopy (cryo-SEM) to obtain direct evidence of the presence of surfactant aggregates in the gel, and to investigate the detailed microstructure for different surfactants. The images show a distribution of nano pores inside the surfactant-laden hydrogels which we speculate are regions of surfactant aggregates, possibly vesicles that have a high affinity for the hydrophobic drug molecule. The gels are further characterized by studying their mechanical and physical properties such as transparency, surface contact angle and equilibrium water content to determine their suitability as extended wear contact lenses. Results show that Brij surfactant-laden p-HEMA gels provide extended release of CyA, and possess suitable mechanical and optical properties for contact lens applications. The gels are not as effective for extended release of two other hydrophobic ophthalmic drugs, dexamethasone (DMS) and dexamethasone 21 acetate (DMSA) because of insufficient partitioning inside the surfactant aggregates.

  14. 3-Dimensional cell-laden nano-hydroxyapatite/protein hydrogels for bone regeneration applications

    Energy Technology Data Exchange (ETDEWEB)

    Sadat-Shojai, Mehdi, E-mail: [Department of Chemistry, College of Sciences, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of); Department of Biomaterials, Iran Polymer and Petrochemical Institute, Tehran (Iran, Islamic Republic of); Khorasani, Mohammad-Taghi [Department of Biomaterials, Iran Polymer and Petrochemical Institute, Tehran (Iran, Islamic Republic of); Jamshidi, Ahmad [Department of Novel Drug Delivery Systems, Iran Polymer and Petrochemical Institute, Tehran (Iran, Islamic Republic of)


    The ability to encapsulate cells in three-dimensional (3D) protein-based hydrogels is potentially of benefit for tissue engineering and regenerative medicine. However, as a result of their poor mechanical strength, protein-based hydrogels have traditionally been considered for soft tissue engineering only. Hence, in this study we tried to render these hydrogels suitable for hard tissue regeneration, simply by incorporation of bioactive nano-hydroxyapatite (HAp) into a photocrosslinkable gelatin hydrogel. Different cell types were also encapsulated in three dimensions in the resulting composites to prepare cell-laden constructs. According to the results, HAp significantly improves the stiffness of gelatin hydrogels, while it maintains their structural integrity and swelling ratio. It was also found that while the bare hydrogel (control) was completely inert in terms of bioactivity, a homogeneous 3D mineralization occurs throughout the nanocomposites after incubation in simulated body fluid. Moreover, encapsulated cells readily elongated, proliferated, and formed a 3D interconnected network with neighboring cells in the nanocomposite, showing the suitability of the nano-HAp/protein hydrogels for cellular growth in 3D. Therefore, the hydrogel nanocomposites developed in this study may be promising candidates for preparing cell-laden tissue-like structures with enhanced stiffness and increased osteoconductivity to induce bone formation in vivo. - Highlights: • We tried to render protein-based hydrogels suitable for hard tissue regeneration. • We developed a three-component system comprising hydrogel, nano-HAp, and cells. • Nano-HAp significantly improved the mechanical strength of hydrogel. • Encapsulated cells readily elongated and proliferated in 3D cell-laden nanocomposite. • 3D deposition of bone crystals occurred in the hydrogel nanocomposites.

  15. Visualizing the internal structure of subaqueous, high-concentration sediment-laden flows: implication of rheology to flow structure (United States)

    Perillo, M. M.; Buttles, J.; Mohrig, D. C.; Kane, I.; Pontén, A.; Brown, D.; Minton, B. W.


    Subaqueous sediment-laden flows are thought to be the main mechanism transporting sediments to the deep sea. Understanding the processes governing these flows is crucial to building predictive models of flow behaviour, sediment transport and deposition and is applicable to a wide range of disciplines. Physical modelling using a wide range of experimental facilities and measurement techniques has significantly advanced our understanding of these sediment-laden flows and their ability to erode, transport and deposit sediments. However, for the case of high-sediment concentration flows, measuring flow and depositional properties is still a challenge. Here, we present results from an acoustic reflection technique that allows for direct and noninvasive visualization of the internal structure of high concentration, clay-rich, sand-laden flows with a range of initial yield strengths (0-26 Pa). As the acoustic signal travels through the sediment-laden flow, it encounters zones of varying acoustic impedance that are due to temporal and spatial changes in sediment concentration, grain size and sorting, and flow mixing. The reflected signal is processed and interpreted using seismic techniques developed in exploration geophysics. The ultrasonic reflection data captured two distinct flow stages, an active stage and a post-depositional creeping stage. The clay-rich sand-laden flows showed stratification expressed by three clear vertical zones: (a) an upper relatively dilute turbulent zone, (b) a zone with high sediment concentration and significantly reduced mixing and (c) an aggrading bed of static grains.

  16. Bone-repair properties of biodegradable hydroxyapatite nano-rod superstructures (United States)

    D'Elía, Noelia L.; Mathieu, Colleen; Hoemann, Caroline D.; Laiuppa, Juan A.; Santillán, Graciela E.; Messina, Paula V.


    Nano-hydroxyapatite (nano-HAp) materials show an analogous chemical composition to the biogenic mineral components of calcified tissues and depending on their topography they may mimic the specific arrangement of the crystals in bone. In this work, we have evaluated the potential of four synthesized nano-HAp superstructures for the in vitro conditions of bone-repair. Experiments are underway to investigate the effects of the material microstructure, surface roughness and hydrophilicity on their osseo-integration, osteo-conduction and osteo-induction abilities. Materials were tested in the presence of both, rat primary osteoblasts and rabbit mesenchymal stem cells. The following aspects are discussed: (i) cytotoxicity and material degradation; (ii) rat osteoblast spreading, proliferation and differentiation; and (iii) rabbit mesenchymal stem cell adhesion on nano-HAp and nano-HAp/collagen type I coatings. We effectively prepared a material based on biomimetic HAp nano-rods displaying the appropriate surface topography, hydrophilicity and degradation properties to induce the in vitro desired cellular responses for bone bonding and healing. Cells seeded on the selected material readily attached, proliferated and differentiated, as confirmed by cell viability, mitochondrial metabolic activity, alkaline phosphatase (ALP) activity and cytoskeletal integrity analysis by immunofluorescence localization of alpha-smooth muscle actin (α-SMA) protein. These results highlight the influence of material's surface characteristics to determine their tissue regeneration potential and their future use in engineering osteogenic scaffolds for orthopedic implants.Nano-hydroxyapatite (nano-HAp) materials show an analogous chemical composition to the biogenic mineral components of calcified tissues and depending on their topography they may mimic the specific arrangement of the crystals in bone. In this work, we have evaluated the potential of four synthesized nano-HAp superstructures

  17. Propagation and deposition of non-circular finite release particle-laden currents


    Zgheib, Nadim; Bonometti, Thomas; Balachandar, Sivaramakrishnan


    International audience; The dynamics of non-axisymmetric turbidity currents is considered here for a range of Reynolds numbers of O(10^4) when based on the initial height of the release. The study comprises a series of experiments and highly resolved simulations for which a finite volume of particle-laden solution is released into fresh water. A mixture of water and polystyrene particles of mean diameter dp=300 μm and mixture density ρc=1012 kg/m^3 is initially confined in a hollow cylinder a...

  18. Surfactant-laden drop jellyfish-breakup mode induced by the Marangoni effect (United States)

    Zhao, Hui; Zhang, Wen-Bin; Xu, Jian-Liang; Li, Wei-Feng; Liu, Hai-Feng


    Drop breakup is a familiar event in both nature and technology. In this study, we find that the bag breakup mode can be replaced by a new breakup mode: jellyfish breakup, when the surfactant concentration of a surfactant-laden drop is high. This new breakup mode has a morphology resembling a jellyfish with many long tentacles. This is due to the inhomogeneous distribution of surfactant in the process of drop deformation and breakup. The thin film of liquid can remain stable as a result of the Marangoni effect. Finally, we propose that the dimensionless surfactant concentration can serve as a criterion for breakup mechanisms.

  19. AEROFROSH: a shock condition calculator for multi-component fuel aerosol-laden flows (United States)

    Campbell, M. F.; Haylett, D. R.; Davidson, D. F.; Hanson, R. K.


    This article introduces an algorithm that determines the thermodynamic conditions behind incident and reflected shocks in aerosol-laden flows. Importantly, the algorithm accounts for the effects of droplet evaporation on post-shock properties. Additionally, this article describes an algorithm for resolving the effects of multiple-component-fuel droplets. This article presents the solution methodology and compares the results to those of another similar shock calculator. It also provides examples to show the impact of droplets on post-shock properties and the impact that multi-component fuel droplets have on shock experimental parameters. Finally, this paper presents a detailed uncertainty analysis of this algorithm's calculations given typical experimental uncertainties.

  20. A novel incompressible finite-difference lattice Boltzmann equation for particle-laden flow

    Institute of Scientific and Technical Information of China (English)

    Sheng Chen; Zhaohui Liu; Baochang Shi; Zhu He; Chuguang Zheng


    In this paper, we propose a novel incompressible finite-difference lattice Boltzmann Equation (FDLBE). Because source terms that reflect the interaction between phases can be accurately described, the new model is suitable for simulating two-way coupling incompressible multiphase flow.The 2-D particle-laden flow over a backward-facing step is chosen as a test case to validate the present method. Favorable results are obtained and the present scheme is shown to have good prospects in practical applications.


    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.; Ronald D. Neufeld; Jana Agostini


    This sixteenth quarterly report describes work done during the sixteenth three-month period of the University of Pittsburgh's project on the ''Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.'' This report describes the activities of the project team during the reporting period. The principal work has focused upon new laboratory evaluation of samples from Phase 1, discussions with MAX Environmental Technologies, Inc., on the field work of Phase 2, giving a presentation, and making and responding to several outside contacts.

  2. Geophysical granular and particle-laden flows: review of the field. (United States)

    Hutter, Kolumban


    An introduction is given to the title theme, in general, and the specific topics treated in detail in the articles of this theme issue of the Philosophical Transactions. They fit into the following broader subjects: (i) dense, dry and wet granular flows as avalanche and debris flow events, (ii) air-borne particle-laden turbulent flows in air over a granular base as exemplified in gravity currents, aeolian transport of sand, dust and snow and (iii) transport of a granular mass on a two-dimensional surface in ripple formations of estuaries and rivers and the motion of sea ice.

  3. Dilatational viscosity of dilute particle-laden fluid interface at different contact angles (United States)

    Lishchuk, Sergey V.


    We consider a solid spherical particle adsorbed at a flat interface between two immiscible fluids and having arbitrary contact angle at the triple contact line. We derive analytically the flow field corresponding to dilatational surface flow in the case of a large ratio of dynamic shear viscosities of two fluids. Considering a dilute assembly of such particles we calculate numerically the dependence on the contact angle of the effective surface dilatational viscosity particle-laden fluid interface. The effective surface dilatational viscosity is proportional to the size and surface concentration of particles and monotonically increases with the increase in protrusion of particles into the fluid with larger shear viscosity.


    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.; Ronald D. Neufeld; Jana Agostini


    This fourteenth quarterly report describes work done during the fourteenth three-month period of the University of Pittsburgh's project on the ''Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.'' This report describes the activities of the project team during the reporting period. The principal work has focused upon new laboratory evaluation of samples from Phase 1, discussions with MAX Environmental Technologies, Inc., on the field work of Phase 2, preparing presentations, and making and responding to two outside contacts.


    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.; Ronald D. Neufeld; Jana Agostini


    This fifteenth quarterly report describes work done during the fifteenth three-month period of the University of Pittsburgh's project on the ''Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.'' This report describes the activities of the project team during the reporting period. The principal work has focused upon new laboratory evaluation of samples from Phase 1, discussions with MAX Environmental Technologies, Inc., on the field work of Phase 2, preparing and giving presentations, and making and responding to several outside contacts.

  6. Treatment of metal-laden hazardous wastes with advanced Clean Coal Technology by-products

    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.; Ronald D. Neufeld; Jana Agostini; Wiles Elder


    This eleventh quarterly report describes work done during the eleventh three-month period of the University of Pittsburgh's project on the ``Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.'' This report describes the activities of the project team during the reporting period. The principal work has focused upon new laboratory evaluation of samples from Phase 1, discussions with MAX Environmental Technologies, Inc., on the field work of Phase 2, preparing and giving presentations, and making and responding to two outside contacts.

  7. System identification of superstructures with rocking motion and deformation of bases; Kiso ga henkeishi rocking suru kozobutsu no shindo tokusei suiteiho

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K.; Naito, Y.; Uchiyama, S.; Maeda, T.; Matsuda, K. [Kajima Corp., Tokyo (Japan)


    Transfer functions of individual parts against bases are generally used as a method for estimating dynamic characteristics of superstructures from observation records of earthquakes or microtremors. However, since soil-structure-interaction (SSI) is included in the observation records, it is difficult to clarify the dynamic characteristics of superstructures, independently. A method has been previously proposed, by which the dynamic characteristics of superstructures without the effect of SSI can be estimated by restricting the vibration mode using equivalent height even in the case of the ground motion condition for multi-particle systems as same as in the case of that for one-particle systems. In this study, this method has been applied to models of SSI systems with rocking and deformation of bases, to estimate the dynamic characteristics of superstructures for ground motion and top excitation conditions. Rigidity of bases was varied as a parameter. Consequently, it was confirmed that the present method can provide accurate estimates of dynamic characteristics of superstructures for both ground motion and top excitation conditions if deformation of bases is not so large. 2 refs., 11 figs., 3 tabs.

  8. A Simplified Model of a Reinforced Square Hollow Section (SHS) T-Joint for Stress Evaluation in Bus Superstructures (United States)

    Vichiensamuth, T.; Pimsarn, M.; Takahashi, K.; Tantanawat, T.


    This study aims to create a simplified model of a reinforced square hollow section (SHS) T-joint found in bus superstructures. The approach is to use a combination of one- and two-dimensional finite element models to represent a reference three-dimensional finite element (solid) model of the joint and determine stress concentration factors (SCFs) as functions of the geometrical variables of the joint. This approach requires the stiffness of the simplified model to be equivalent to the stiffness of the reference solid model. Trial models, therefore, must be proposed and their stiffnesses must be evaluated against the stiffness of the reference solid model. The best trial model is then selected based on the stiffness error function defined to represent the deviation of the simplified model's stiffness from the reference model's stiffness. After a trial model with minimum stiffness error is selected, its SCFs, relating the maximum stress in the simplified model to the maximum stress in the reference solid model, are determined. Since the maximum stress is assumed to be at the weld toe where structural discontinuity exists, the maximum stresses on both simplified model and reference solid model are evaluated based on a hot spot stress (HSS) method. In this study, three trial models, namely Model A, Model B, and Model C, were investigated. Model B, consisting of beam and shell elements with particular constraints on the joint-reinforcement geometry, was found to provide the minimum stiffness errors of 8.09%, 6.87%, and 6.44% for three different joint dimensions. The SCFs were then determined as a function of the thickness-to-width ratio of the joint under static in-plane bending load. The resulting simplified model allows the stress evaluation on the bus superstructures to be done more quickly compared to a solid model while maintaining the accuracy of the solutions. Consequently, the designs of bus superstructures can be explored more thoroughly, leading to a better

  9. Incorporating Volumetric Displacement Effects In Euler-Lagrange Simulations of Particle-Laden Oscillatory Flows (United States)

    Apte, Sourabh; Finn, Justin; Cihonski, Andrew


    Recent Euler-Lagrange discrete element modeling of a few microbubbles entrained in a traveling vortex ring (Cihonski et al., JFM, 2013) has shown that extension of the point-particle method to include local volume displacement effects is critical for capturing vortex distortion effects due to microbubbles, even in a very dilute suspension. We extend this approach to investigate particle-laden oscillatory boundary layers representative of coastal sediment environments. A wall bounded, doubly periodic domain is considered laden with a layer of sediment particles in laminar as well as turbulent oscillatory boundary layers corresponding to the experiments of Keiller and Sleath (1987) and Jensen et al. (1987). Inter-particle and particle-wall collisions are modeled using a soft-sphere model which uses a nested collision grid to minimize computational effort. The effects of fluid mass displaced by the particles on the flow statistics are quantified by comparing a standard two-way coupling approach (without volume displacement effects) with volume displacement effects to show that the latter models are important for low cases with low particle-fluid density ratios. NSF project #1133363, Sediment-Bed-Turbulence Coupling in Oscillatory Flows. EPSRC Project # EP/J00507X/1, EP/J005541/1 Sand Transport under Irregular and Breaking Waves Conditions (SINBAD).

  10. Fabrication of uniformly cell-laden porous scaffolds using a gas-in-liquid templating technique. (United States)

    Takei, Takayuki; Aokawa, Ryuta; Shigemitsu, Takamasa; Kawakami, Koei; Yoshida, Masahiro


    Design of porous scaffolds in tissue engineering field was challenging. Uniform immobilization of cells in the scaffolds with high porosity was essential for homogeneous tissue formation. The present study was aimed at fabricating uniformly cell-laden porous scaffolds with porosity >74% using the gas-in-liquid foam templating technique. To this end, we used gelatin, microbial transglutaminase and argon gas as a scaffold material, cross-linker of the protein and porogen of scaffold, respectively. We confirmed that a porosity of >74% could be achieved by increasing the gas volume delivered to a gelatin solution. Pore size in the scaffold could be controlled by stirring speed, stirring time and the pore size of the filter through which the gas passed. The foaming technique enabled us to uniformly immobilize a human hepatoblastoma cell line in scaffold. Engraftment efficiency of the cell line entrapped within the scaffold in nude mice was higher than that of cells in free-form. These results showed that the uniformly cell-laden porous scaffolds were promising for tissue engineering.

  11. Effects of clustering on heat transfer in particle-laden turbulence (United States)

    Pouransari, Hadi; Mani, Ali


    Particle-laden flows are ubiquitous in variety of natural and industrial phenomena. Rain droplets in clouds, protoplanetary disks, and combustion chambers are examples in which particles are interacting with a background turbulence. It is well known that interaction of particles and turbulent flow results in preferential concentration. The extent of preferential concentration depends on ratio of particle relaxation time and turbulent eddies time scale.this work, we consider particle-laden turbulent flows, in which particles are heated. This is the case for example in the particle-based solar receivers where particles absorb external radiation and heat the background gas. We use three-dimensional variable density direct numerical simulations for the turbulent flow and Lagrangian point-particle tracking to study the implication of particle clustering in particle-to-gas heat transfer. We investigate variety of non-dimensional numbers including particle Stokes number, Reynolds number, and mass loading ratio. Using our statistical analyses we introduce a model to correct the particle-to-gas heat transfer to account for particle clustering. This can be employed in Reynolds average Navier Stokes (RANS) computations. Supported by DOE under PSAAP2 program at Stanford University.


    Institute of Scientific and Technical Information of China (English)

    LI Dan-xun; LIN Qiu-sheng; ZHONG Qiang; WANG Xing-kui


    Sediment-laden flow measurement with Particle Tracking Velocimetry (PTV) introduces a series of finite-sized sampling bins along the vertical of the flow.Instantaneous velocities are collected at each bin and a significantly large sample is established to evaluate mean and root mean square (rms) velocities of the flow.Due to the presence of concentration gradient,the established sample for the solid phase inv(o)lves more data from the lower part of the sampling bin than from the upper part.The concentration effect causes bias errors in the measured mean and rms velocities when velocity varies across the bin.These bias errors are analytically quantified in this study based on simplified linear velocity and concentration distributions.Typical bulk flow characteristics from sediment-laden flow measurements are used to demonstrate rough estimation of the error magnitude.Results indicate that the mean velocity is underestimated while the rms velocity is overestimated in the ensemble-averaged measurement.The extent of deviation is commensurate with the bin size and the rate of concentration gradient.Procedures are proposed to assist determining an appropriate sampling bin size in certain error limits.

  13. Small gold nanorods laden macrophages for enhanced tumor coverage in photothermal therapy. (United States)

    Li, Zhibin; Huang, Hao; Tang, Siying; Li, Yong; Yu, Xue-Feng; Wang, Huaiyu; Li, Penghui; Sun, Zhengbo; Zhang, Han; Liu, Chenli; Chu, Paul K


    One of the challenges to adopt photothermal ablation clinically is optimization of the agent delivery in vivo. Herein, a cell-mediated delivery and therapy system by employing macrophage vehicles to transport 7 nm diameter Au nanorods (sAuNRs) is described. Owing to the small size, the sAuNRs exhibit much higher macrophage uptake and negligible cytotoxicity in comparison with commonly used 14 nm diameter AuNRs to achieve healthy BSA-coated sAuNRs-laden-macrophages. By delivering BSA-coated sAuNRs to the entire tumor after intratumoral injection, the BSA-coated sAuNRs-laden-macrophages show greatly improved photothermal conversion almost everywhere in the tumor, resulting in minimized tumor recurrence rates compared to free BSA-coated sAuNRs. Our findings not only provide a desirable approach to improve the photothermal therapy efficiency by optimizing the intratumoral distribution of the agents, but also expedite clinical application of nanotechnology to cancer treatment.

  14. Hydrogel-laden paper scaffold system for origami-based tissue engineering. (United States)

    Kim, Su-Hwan; Lee, Hak Rae; Yu, Seung Jung; Han, Min-Eui; Lee, Doh Young; Kim, Soo Yeon; Ahn, Hee-Jin; Han, Mi-Jung; Lee, Tae-Ik; Kim, Taek-Soo; Kwon, Seong Keun; Im, Sung Gap; Hwang, Nathaniel S


    In this study, we present a method for assembling biofunctionalized paper into a multiform structured scaffold system for reliable tissue regeneration using an origami-based approach. The surface of a paper was conformally modified with a poly(styrene-co-maleic anhydride) layer via initiated chemical vapor deposition followed by the immobilization of poly-l-lysine (PLL) and deposition of Ca(2+). This procedure ensures the formation of alginate hydrogel on the paper due to Ca(2+) diffusion. Furthermore, strong adhesion of the alginate hydrogel on the paper onto the paper substrate was achieved due to an electrostatic interaction between the alginate and PLL. The developed scaffold system was versatile and allowed area-selective cell seeding. Also, the hydrogel-laden paper could be folded freely into 3D tissue-like structures using a simple origami-based method. The cylindrically constructed paper scaffold system with chondrocytes was applied into a three-ring defect trachea in rabbits. The transplanted engineered tissues replaced the native trachea without stenosis after 4 wks. As for the custom-built scaffold system, the hydrogel-laden paper system will provide a robust and facile method for the formation of tissues mimicking native tissue constructs.

  15. Spinel formation for stabilizing simulated nickel-laden sludge with aluminum-rich ceramic precursors. (United States)

    Shih, Kaimin; White, Tim; Leckie, James O


    The feasibility of stabilizing nickel-laden sludge from commonly available Al-rich ceramic precursors was investigated and accomplished with high nickel incorporation efficiency. To simulate the process, nickel oxide was mixed alternatively with gamma-alumina, corundum, kaolinite, and mullite and was sintered from 800 to 1480 degrees C. The nickel aluminate spinel (NiAl2O4) was confirmed as the stabilization phase for nickel and crystallized with efficiencies greater than 90% for all precursors above 1250 degrees C and 3-h sintering. The nickel-incorporation reaction pathways with these precursors were identified, and the microstructure and spinel yield were investigated as a function of sintering temperature with fixed sintering time. This study has demonstrated a promising process for forming nickel spinel to stabilize nickel-laden sludge from a wide range of inexpensive ceramic precursors, which may provide an avenue for economically blending waste metal sludges via the building industry processes to reduce the environmental hazards of toxic metals. The correlation of product textures and nickel incorporation efficiencies through selection of different precursors also provides the option of tailoring property-specific products.

  16. Particle-laden jets: particle distribution and back-reaction on the flow

    Energy Technology Data Exchange (ETDEWEB)

    Picano, F; Sardina, G; Gualtieri, P; Casciola, C M, E-mail: [Dipartimento di Ingegneria Meccanica e Aeronautica, ' La Sapienza' University of Rome (Italy)


    DNS data of particle-laden jets are discussed both in the one- and two-way coupling regimes. Dynamics of inertial particles in turbulent jets is characterized by an anomalous transport that leads to the formation of particle concentration peaks along the jet axis. Larger is the particle inertia farther the peak location occurs. The controlling parameter is found to be the local large-scale Stokes number which decreases quadratically with the axial distance and is order one in coincidence of the peaks. The centerline mean particle velocity is characterized by two scaling laws. The former occurs upstream the location where the Stokes number is order one, and is linear in the axial distance with negative coefficient. The latter, occurring downstream where the local Stokes number is small, coincides with that of the centerline mean fluid velocity. This behavior affects the development of the particle-laden jet when the mass load of the particulate phase increases and two-way coupling effects become relevant. Two distinct behaviors for the jet development are found behind and beyond the location of unity local Stokes number leading to different scaling laws for the mean centerline fluid velocity.

  17. Hemisphere-specific treatment of dyslexia subtypes: better reading with anxiety-laden words? (United States)

    Van Strien, J W; Stolk, B D; Zuiker, S


    Twenty children (12 boys, 8 girls; mean age = 10.4 years) with P-type dyslexia (accurate but slow and fragmented reading) and 20 children (12 boys, 8 girls; mean age = 10.3 years) with L-type dyslexia (hurried, inaccurate reading) were treated with visual hemisphere-specific stimulation employing the HEMSTIM computer program. Stimulation was produced by presenting words to the left (L-dyslexia) or to the right (P-dyslexia) visual field. Children in the control condition received treatment with neutral words, whereas children in the experimental condition received treatment with anxiety-laden words. After treatment, the children with L-dyslexia in the experimental group made fewer substantive errors and more fragmentations on a text-reading task than did the children with L-dyslexia in the control group. The results are explained as being the consequence of additional activation of the right hemisphere caused by the anxiety-laden words. It is concluded that children with L-dyslexia can benefit from the use of such words in the HEMSTIM program.

  18. Contact assembly of cell-laden hollow microtubes through automated micromanipulator tip locating (United States)

    Wang, Huaping; Shi, Qing; Guo, Yanan; Li, Yanan; Sun, Tao; Huang, Qiang; Fukuda, Toshio


    This paper presents an automated contact assembly method to fabricate a cell-laden microtube based on accurate locating of the micromanipulator tip. Essential for delivering nutrients in thick engineered tissues, a vessel-mimetic microtube can be precisely assembled through microrobotic contact biomanipulation. The biomanipulation is a technique to spatially order and immobilize cellular targets with high precision. However, due to image occlusion during contact, it is challenging to locate the micromanipulator tip for fully automated assembly. To achieve pixel-wise tracking and locating of the tip in contact, a particle filter algorithm integrated with a determined level set model is employed here. The model ensures precise convergence of the micromanipulator’s contour during occlusion. With the converged active contour, the algorithm is able to pixel-wisely separate the micromanipulator from the low-contrast background and precisely locate the tip with error around 1 pixel (2 µm at 4  ×  magnification). As a result, the cell-laden microtube is automatically assembled at six layers/min, which is effective enough to fabricate vessel-mimetic constructs for vascularization in tissue engineering.

  19. The Phase Transition of Nematic Liquid Crystal Cells Bounded by Surfactant-Laden Interfaces

    Institute of Scientific and Technical Information of China (English)

    ZENG Ming-Ying; CUI Wei; TAN Xiao-Qin; WU Chen-Xu


    @@ Taking into account the surface-coupling strength effect, we discuss the phase transitions of a finite thickness cell bounded by surfactant-laden interfaces in a magnetic field perpendicular to the substrate and it is compared with that of a semi-infinite system.It is found that the larger the thickness, the closer the three-dimensional phase transition surfacc of the finite system to that of the semi-infinite one.The simulation also shows that when a magnetic field is applied to a nematic semi-infinite sample, an orientational phase transition first takes place close to the interface and thcn extends to the inner space as the temperature increases.%Taking into account the surface-coupling strength effect, we discuss the phase transitions of a finite thickness cell bounded by surfactant-laden interfaces in a magnetic field perpendicular to the substrate and it is compared with that of a semi-infinite system. It is found that the larger the thickness, the closer the three-dimensional phase transition surface of the finite system to that of the semi-infinite one. The simulation also shows that when a magnetic field is applied to a nernatic semi-infinite sample, an orientational phase transition first takes place close to the interface and then extends to the inner space as the temperature increases.

  20. Influence of lubrication forces in direct numerical simulations of particle-laden flows (United States)

    Maitri, Rohit; Peters, Frank; Padding, Johan; Kuipers, Hans


    Accurate numerical representation of particle-laden flows is important for fundamental understanding and optimizing the complex processes such as proppant transport in fracking. Liquid-solid flows are fundamentally different from gas-solid flows because of lower density ratios (solid to fluid) and non-negligible lubrication forces. In this interface resolved model, fluid-solid coupling is achieved by incorporating the no-slip boundary condition implicitly at particle's surfaces by means of an efficient second order ghost-cell immersed boundary method. A fixed Eulerian grid is used for solving the Navier-Stokes equations and the particle-particle interactions are implemented using the soft sphere collision and sub-grid scale lubrication model. Due to the range of influence of lubrication force on a smaller scale than the grid size, it is important to implement the lubrication model accurately. In this work, different implementations of the lubrication model on particle dynamics are studied for various flow conditions. The effect of a particle surface roughness on lubrication force and the particle transport is also investigated. This study is aimed at developing a validated methodology to incorporate lubrication models in direct numerical simulation of particle laden flows. This research is supported from Grant 13CSER014 of the Foundation for Fundamental Research on Matter (FOM), which is part of the Netherlands Organisation for Scientific Research (NWO).

  1. Rapid Fabrication of Cell-Laden Alginate Hydrogel 3D Structures by Micro Dip-Coating (United States)

    Ghanizadeh Tabriz, Atabak; Mills, Christopher G.; Mullins, John J.; Davies, Jamie A.; Shu, Wenmiao


    Development of a simple, straightforward 3D fabrication method to culture cells in 3D, without relying on any complex fabrication methods, remains a challenge. In this paper, we describe a new technique that allows fabrication of scalable 3D cell-laden hydrogel structures easily, without complex machinery: the technique can be done using only apparatus already available in a typical cell biology laboratory. The fabrication method involves micro dip-coating of cell-laden hydrogels covering the surface of a metal bar, into the cross-linking reagents calcium chloride or barium chloride to form hollow tubular structures. This method can be used to form single layers with thickness ranging from 126 to 220 µm or multilayered tubular structures. This fabrication method uses alginate hydrogel as the primary biomaterial and a secondary biomaterial can be added depending on the desired application. We demonstrate the feasibility of this method, with survival rate over 75% immediately after fabrication and normal responsiveness of cells within these tubular structures using mouse dermal embryonic fibroblast cells and human embryonic kidney 293 cells containing a tetracycline-responsive, red fluorescent protein (tHEK cells). PMID:28286747

  2. Three-dimensional fiber deposition of cell-laden, viable, patterned constructs for bone tissue printing. (United States)

    Fedorovich, Natalja E; De Wijn, Joost R; Verbout, Abraham J; Alblas, Jacqueline; Dhert, Wouter J A


    Organ or tissue printing, a novel approach in tissue engineering, creates layered, cell-laden hydrogel scaffolds with a defined three-dimensional (3D) structure and organized cell placement. In applying the concept of tissue printing for the development of vascularized bone grafts, the primary focus lies on combining endothelial progenitors and bone marrow stromal cells (BMSCs). Here we characterize the applicability of 3D fiber deposition with a plotting device, Bioplotter, for the fabrication of spatially organized, cell-laden hydrogel constructs. The viability of printed BMSCs was studied in time, in several hydrogels, and extruded from different needle diameters. Our findings indicate that cells survive the extrusion and that their subsequent viability was not different from that of unprinted cells. The applied extrusion conditions did not affect cell survival, and BMSCs could subsequently differentiate along the osteoblast lineage. Furthermore, we were able to combine two distinct cell populations within a single scaffold by exchanging the printing syringe during deposition, indicating that this 3D fiber deposition system is suited for the development of bone grafts containing multiple cell types.

  3. Co-opting Science: A preliminary study of how students invoke science in value-laden discussions

    DEFF Research Database (Denmark)

    Nielsen, J. A.


    Letting students deliberate on socio-scientific issues is a tricky affair. It is yet unclear how to assess whether, or even support that, students weave science facts into value-laden socio-scientific deliberations without committing the naturalistic fallacy of deducing 'ought' from 'is'. As a pr......Letting students deliberate on socio-scientific issues is a tricky affair. It is yet unclear how to assess whether, or even support that, students weave science facts into value-laden socio-scientific deliberations without committing the naturalistic fallacy of deducing 'ought' from 'is...

  4. Cellulose acetate-directed growth of bamboo-raft-like single-crystalline selenium superstructures: high-yield synthesis, characterization, and formation mechanism. (United States)

    Song, Ji-Ming; Zhan, Yong-Jie; Xu, An-Wu; Yu, Shu-Hong


    High-yield synthesis of bamboo-raft-like single-crystalline selenium superstructures has been realized for the first time via a facile solvothermal approach by reducing SeO2 with ethylene alcohol in the presence of cellulose acetate. The formation of a raftlike superstructure with various forms is strongly dependent on the temperature, amount of cellulose acetate, reaction time, and even preheating treatment. The suitable amount of cellulose acetate is essential for the formation of elegant and uniform raft Se. The morphology, microstructure, optical properties, and chemical compositions of bamboo-raft-like selenium were characterized using various techniques (X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy (TEM), high-resolution (HR) TEM, X-ray photoelectron spectroscopy, UV-vis spectroscopy, FTIR spectroscopy, and Raman spectroscopy). A possible growth mechanism has been proposed. Such special superstructures could provide a useful precursor for potential applications.

  5. Self-organization of nickel nanoparticles dispersed in acetone: From separate nanoparticles to three-dimensional superstructures

    Directory of Open Access Journals (Sweden)

    I. Hernández-Pérez


    Full Text Available Sonochemical synthesis of monodisperse nickel nanoparticles (Ni-NPs by reduction of Ni acetylacetonate in the presence of polyvinylpyrrolidone stabilizer is reported. The Ni-NPs size is readily controlled to 5 nanometer diameter with a standard deviation of less than 5%. The as-prepared Ni-NPs sample was dispersed in acetone, for 4 weeks. For structural analysis was not applied to a magnetic field or heat treatment as key methods to direct the assembly. The transition from separate Ni-NPs into self-organization of three dimensions (3D superstructures was studied by electron microscopy. Experimental analysis suggests that the translation and rotation movement of the Ni-NPs are governed by magnetic frustration which promotes the formation of different geometric arrangements in two dimensions (2D. The formation of 3D superstructures is confirmed from scanning electron microscopy revealing a layered domain that consists of staking of several monolayers having multiple well-defined supercrystalline domains, enabling their use for optical, electronic and sensor applications.

  6. Facile hydrothermal synthesis of TiO2-Bi2WO6 hollow superstructures with excellent photocatalysis and recycle properties. (United States)

    Hou, Ya-Fei; Liu, Shu-Juan; Zhang, Jing-huai; Cheng, Xiao; Wang, You


    One-dimensional mesoporous TiO2-Bi2WO6 hollow superstructures are prepared using a hydrothermal method and their photocatalysis and recycle properties are investigated. Experimental results indicate that anatase TiO2 nanoparticles are coupled with hierarchical Bi2WO6 hollow tubes on their surfaces. The TiO2-Bi2WO6 structure has a mesoporous wall and the pores in the wall are on average 21 nm. The hierarchical TiO2-Bi2WO6 heterostructures exhibit the highest photocatalytic activity in comparison with P25, pure Bi2WO6 hollow tube and mechanical mixture of Bi2WO6 tube and TiO2 nanoparticle in the degradation of rhodamine B (RhB) under simulated sunlight irradiation. The as-prepared TiO2-Bi2WO6 heterostructures can be easily recycled through sedimentation and they retains their high photocatalytic activity during the cycling use in the simulated sunlight-driving photodegradation process of RhB. The prepared mesoporous TiO2-Bi2WO6 with hollow superstructure is therefore a promising candidate material for water decontamination use.

  7. Ultra-high-speed digital in-line holography system applied to particle-laden supersonic underexpanded jet flows

    DEFF Research Database (Denmark)

    Ingvorsen, Kristian Mark; Buchmann, Nicolas A.; Soria, Julio


    for magnified digital in-line holography is created, using an ultra-high-speed camera capable of frame rates of up to 1.0MHz. To test the new technique an axisymmetric supersonic underexpanded particle-laden jet is investigated. The results show that the new technique allows for the acquisition of time resolved...

  8. Lattice-Boltzmann simulation of particle-laden flow over a backward-facing step

    Institute of Scientific and Technical Information of China (English)

    Chen Sheng; Shi Bao-Chang; Liu Zhao-Hui; He Zhu; Gno Zhao-Li; Zheng Chu-Guang


    This paper deals with the numerical simulation of gas-solid two-phase flows in an Eulerian-Lagrangian scheme.The particle tracks are calculated using a recently developed exponential Lagrangian scheme, and the approach presently used for the computation of fluid phase is based on a modified Lattice-BGK model. Different from earlier publications,the present study employs a two-way coupling mechanism to handle the interactions between carrier phase and dispersed phase in the model. This new model is applicable to simulating gas-solid two-phase flows. For example, based on the scheme, we have recaptured some phenomena of planar laminar particle-laden flow over a backward-facing step in this research, and found a new interesting phenomenon.

  9. Drag reduction in turbulent channel flow laden with finite-size oblate spheroids

    CERN Document Server

    Ardekani, M Niazi; Breugem, W -P; Picano, F; Brandt, L


    We study suspensions of oblate rigid particles in a viscous fluid for different values of the particle volume fractions. Direct numerical simulations have been performed using a direct-forcing immersed boundary method to account for the dispersed phase, combined with a soft-sphere collision model and lubrication corrections for short-range particle-particle and particle-wall interactions. We show that the drag is reduced and the turbulent fluctuations attenuated in flows laden with oblate spheroids not only when compared to suspensions of perfect spheres but also to the single phase turbulent flow. In particular, the turbulence activity decreases to lower values than those obtained by only accounting for the effective suspension viscosity. To explain the observed drag reduction we consider the particle dynamics and the interactions of the particles with the turbulent velocity field. We report the lack of the particle layer at the wall observed for spherical particles, which was found to be responsible for inc...

  10. Removal performance and microbial communities in a sequencing batch reactor treating hypersaline phenol-laden wastewater. (United States)

    Jiang, Yu; Wei, Li; Zhang, Huining; Yang, Kai; Wang, Hongyu


    Hypersaline phenol-rich wastewater is hard to be treated by traditional biological systems. In this work, a sequencing batch reactor was used to remove phenol from hypersaline wastewater. The removal performance was evaluated in response to the variations of operating parameters and the microbial diversity was investigated by 454 pyrosequencing. The results showed that the bioreactor had high removal efficiency of phenol and was able to keep stable with the increase of initial phenol concentration. DO, pH, and salinity also affected the phenol removal rate. The most abundant bacterial group was phylum Proteobacteria in the two working conditions, and class Gammaproteobacteria as well as Alphaproteobacteria was predominant subgroup. The abundance of bacterial clusters was notably different along with the variation of operation conditions, resulting in changes of phenol degradation rates. The high removal efficiency of phenol suggested that the reactor might be promising in treating phenol-laden industrial wastewater in high-salt condition.

  11. Precision stacking of nanoparticle laden sessile droplets to control solute deposit morphology (United States)

    Kabi, Prasenjit; Basu, Saptarshi; Sanyal, Apratim; Chaudhuri, Swetaprovo


    Stacking pure solvent droplets on a solid substrate is apparently impossible in the absence of an external force as the second droplet will invariably spill over the first leading to a large wetted area. However, the unique feature that emerges during the drying of a nanoparticle laden droplet is the progressively enlarging thin solid film along the evaporating sessile droplet liquid periphery. This solid interface: the edge of which we shall refer to as the agglomeration front comprises of a thin layer of nanoparticle assembly and can support a carefully dispensed second droplet thereby allowing droplet stacking. It will be shown that the growth of this agglomeration front can also be effectively controlled by the dispensing time difference and the nanoparticle concentration in the two droplets. So far, we are commonly aware of material stacking in solid phase. This letter demonstrates stacking in the liquid phase and control over the thin solid interface growth.

  12. Migration of a surfactant-laden droplet in non-isothermal Poiseuille flow

    CERN Document Server

    Das, Sayan; Som, S K; Chakraborty, Suman


    The motion of a surfactant-laden viscous droplet in the presence of background non-isothermal Poiseuille flow is studied analytically and numerically. Specifically, the effect of interfacial Marangoni stress due to non-uniform distribution of surfactants and temperature at the droplet interface on the velocity and direction of motion of the droplet along the centerline of imposed Poiseuille flow is investigated in the presence of linearly varying temperature field. In the absence of thermal convection, fluid inertia and shape deformation, the interfacial transport of bulk-insoluble surfactants is governed by the surface Peclet number which represents the relative strength of the advective transport of surfactant over the diffusive transport. We obtain analytical solution for small and large values of the surface Peclet number. Numerical solution is obtained for arbitrary surface Peclet number, which compares well with the analytical solution. Depending on the direction of temperature gradient with respect to ...

  13. A hybrid FEM-DEM approach to the simulation of fluid flow laden with many particles (United States)

    Casagrande, Marcus V. S.; Alves, José L. D.; Silva, Carlos E.; Alves, Fábio T.; Elias, Renato N.; Coutinho, Alvaro L. G. A.


    In this work we address a contribution to the study of particle laden fluid flows in scales smaller than TFM (two-fluid models). The hybrid model is based on a Lagrangian-Eulerian approach. A Lagrangian description is used for the particle system employing the discrete element method (DEM), while a fixed Eulerian mesh is used for the fluid phase modeled by the finite element method (FEM). The resulting coupled DEM-FEM model is integrated in time with a subcycling scheme. The aforementioned scheme is applied in the simulation of a seabed current to analyze which mechanisms lead to the emergence of bedload transport and sediment suspension, and also quantify the effective viscosity of the seabed in comparison with the ideal no-slip wall condition. A simulation of a salt plume falling in a fluid column is performed, comparing the main characteristics of the system with an experiment.

  14. Heat transfer in laminar Couette flow laden with rigid spherical particles

    CERN Document Server

    Ardekani, Mehdi Niazi; Picano, Francesco; Brandt, Luca


    We study heat transfer in plane Couette flow laden with rigid spherical particles by means of direct numerical simulations using a direct-forcing immersed boundary method to account for the dispersed phase. A volume of fluid approach is employed to solve the temperature field inside and outside of the particles. We focus on the variation of the heat transfer with the particle Reynolds number, total volume fraction (number of particles) and the ratio between the particle and fluid thermal diffusivity, quantified in terms of an effective suspension diffusivity. We show that, when inertia at the particle scale is negligible, the heat transfer increases with respect to the unladen case following an empirical correlation recently proposed. In addition, an average composite diffusivity can be used to predict the effective diffusivity of the suspension the inertialess regime when varying the molecular diffusion in the two phases. At finite particle inertia, however, the heat transfer increase is significantly larger...

  15. An adaptive finite element approach to modelling sediment laden density currents (United States)

    Parkinson, S.; Hill, J.; Allison, P. A.; Piggott, M. D.


    Modelling sediment-laden density currents at real-world scales is a challenging task. Here we present Fluidity, which uses dynamic adaptive re-meshing to reduce computational costs whilst maintaining sufficient resolution where and when it is required. This allows small-scale processes to be captured in large scale simulations. Density currents, also known as gravity or buoyancy currents, occur wherever two fluids with different densities meet. They can occur at scales of up to hundred kilometres in the ocean when continental shelves collapse. This process releases large quantities of sediment into the ocean which increase the bulk density of the fluid to form a density current. These currents can carry sediment hundreds of kilometres, at speeds of up to a hundred kilometres per hour, over the sea bed. They can be tsunamigenic and they have the potential to cause significant damage to submarine infrastructure, such as submarine telecommunications cables or oil and gas infrastructure. They are also a key process for movement of organic material into the depths of the ocean. Due to this, they play an important role in the global carbon cycle on the Earth, forming a significant component of the stratigraphic record, and their deposits can form useful sources of important hydrocarbons. Modelling large scale sediment laden density currents is a very challenging problem. Particles within the current are suspended by turbulence that occurs at length scales that are several orders of magnitude smaller than the size of the current. Models that resolve the vertical structure of the flow require a very large, highly resolved mesh, and substantial computing power to solve. Here, we verify our adaptive model by comparison with a set of laboratory experiments by Gladstone et al. [1998] on the propagation and sediment deposition of bidisperse gravity currents. Comparisons are also made with fixed mesh solutions, and it is shown that accuracy can be maintained with fewer elements

  16. In Vivo Chondrogenesis in 3D Bioprinted Human Cell-laden Hydrogel Constructs (United States)

    Möller, Thomas; Hägg, Daniel; Brantsing, Camilla; Rotter, Nicole; Apelgren, Peter; Lindahl, Anders; Kölby, Lars; Gatenholm, Paul


    Background: The three-dimensional (3D) bioprinting technology allows creation of 3D constructs in a layer-by-layer fashion utilizing biologically relevant materials such as biopolymers and cells. The aim of this study is to investigate the use of 3D bioprinting in a clinically relevant setting to evaluate the potential of this technique for in vivo chondrogenesis. Methods: Thirty-six nude mice (Balb-C, female) received a 5- × 5- × 1-mm piece of bioprinted cell-laden nanofibrillated cellulose/alginate construct in a subcutaneous pocket. Four groups of printed constructs were used: (1) human (male) nasal chondrocytes (hNCs), (2) human (female) bone marrow–derived mesenchymal stem cells (hBMSCs), (3) coculture of hNCs and hBMSCs in a 20/80 ratio, and (4) Cell-free scaffolds (blank). After 14, 30, and 60 days, the scaffolds were harvested for histological, immunohistochemical, and mechanical analysis. Results: The constructs had good mechanical properties and keep their structural integrity after 60 days of implantation. For both the hNC constructs and the cocultured constructs, a gradual increase of glycosaminoglycan production and hNC proliferation was observed. However, the cocultured group showed a more pronounced cell proliferation and enhanced deposition of human collagen II demonstrated by immunohistochemical analysis. Conclusions: In vivo chondrogenesis in a 3D bioprinted human cell-laden hydrogel construct has been demonstrated. The trophic role of the hBMSCs in stimulating hNC proliferation and matrix deposition in the coculture group suggests the potential of 3D bioprinting of human cartilage for future application in reconstructive surgery. PMID:28280669

  17. Computational modeling of unsteady surfactant-laden liquid plug propagation in neonatal airways (United States)

    Olgac, Ufuk; Muradoglu, Metin


    Surfactant-free and surfactant-laden liquid plug propagation in neonatal airways in various generations representing the upper and lower airways are investigated computationally using a finite-difference/front-tracking method. Emphasis is placed on the unsteady surfactant-laden plug propagation as a model for Surfactant Replacement Therapy (SRT) and airway reopening. The numerical method is designed to solve the evolution equations of the interfacial and bulk surfactant concentrations coupled with the incompressible Navier-Stokes equations. Available experimental data for surfactant Survanta are used to relate surface tension coefficient to surfactant concentration at the interface. It is found that, for the surfactant-free case, the trailing film thickness is in good agreement with Taylor's law for plugs with plug length greater than the airway width. Mechanical stresses that could be injurious to epithelial cells such as pressure and shear stress and their gradients are maximized on the front and rear menisci with increasing magnitudes in the lower generations. These mechanical stresses, especially pressure and pressure gradient, are diminished with the introduction of surfactants. Surfactant is absorbed onto the trailing film and thickens it, eventually leading to either plug rupture or, if totally consumed prior to rupture, to steadily propagating plug. In the upper airways, initially small plugs rupture rapidly and plugs with comparable initial plug length with the airway width persist and propagate steadily. For a more effective SRT treatment, we recommend utilization of plugs with initial plug length greater than the airway width. Increasing surfactant strength or increasing the initially instilled surfactant concentration is found to be ineffective.

  18. Core-shell microparticles for protein sequestration and controlled release of a protein-laden core. (United States)

    Rinker, Torri E; Philbrick, Brandon D; Temenoff, Johnna S


    Development of multifunctional biomaterials that sequester, isolate, and redeliver cell-secreted proteins at a specific timepoint may be required to achieve the level of temporal control needed to more fully regulate tissue regeneration and repair. In response, we fabricated core-shell heparin-poly(ethylene-glycol) (PEG) microparticles (MPs) with a degradable PEG-based shell that can temporally control delivery of protein-laden heparin MPs. Core-shell MPs were fabricated via a re-emulsification technique and the number of heparin MPs per PEG-based shell could be tuned by varying the mass of heparin MPs in the precursor PEG phase. When heparin MPs were loaded with bone morphogenetic protein-2 (BMP-2) and then encapsulated into core-shell MPs, degradable core-shell MPs initiated similar C2C12 cell alkaline phosphatase (ALP) activity as the soluble control, while non-degradable core-shell MPs initiated a significantly lower response (85+19% vs. 9.0+4.8% of the soluble control, respectively). Similarly, when degradable core-shell MPs were formed and then loaded with BMP-2, they induced a ∼7-fold higher C2C12 ALP activity than the soluble control. As C2C12 ALP activity was enhanced by BMP-2, these studies indicated that degradable core-shell MPs were able to deliver a bioactive, BMP-2-laden heparin MP core. Overall, these dynamic core-shell MPs have the potential to sequester, isolate, and then redeliver proteins attached to a heparin core to initiate a cell response, which could be of great benefit to tissue regeneration applications requiring tight temporal control over protein presentation.

  19. Lagrangian filtered density function for LES-based stochastic modelling of turbulent particle-laden flows (United States)

    Innocenti, Alessio; Marchioli, Cristian; Chibbaro, Sergio


    The Eulerian-Lagrangian approach based on Large-Eddy Simulation (LES) is one of the most promising and viable numerical tools to study particle-laden turbulent flows, when the computational cost of Direct Numerical Simulation (DNS) becomes too expensive. The applicability of this approach is however limited if the effects of the Sub-Grid Scales (SGSs) of the flow on particle dynamics are neglected. In this paper, we propose to take these effects into account by means of a Lagrangian stochastic SGS model for the equations of particle motion. The model extends to particle-laden flows the velocity-filtered density function method originally developed for reactive flows. The underlying filtered density function is simulated through a Lagrangian Monte Carlo procedure that solves a set of Stochastic Differential Equations (SDEs) along individual particle trajectories. The resulting model is tested for the reference case of turbulent channel flow, using a hybrid algorithm in which the fluid velocity field is provided by LES and then used to advance the SDEs in time. The model consistency is assessed in the limit of particles with zero inertia, when "duplicate fields" are available from both the Eulerian LES and the Lagrangian tracking. Tests with inertial particles were performed to examine the capability of the model to capture the particle preferential concentration and near-wall segregation. Upon comparison with DNS-based statistics, our results show improved accuracy and considerably reduced errors with respect to the case in which no SGS model is used in the equations of particle motion.

  20. 1H NMR-based metabolomics investigation of copper-laden rat: a model of Wilson's disease.

    Directory of Open Access Journals (Sweden)

    Jingjing Xu

    Full Text Available Wilson's disease (WD, also known as hepatoleticular degeneration (HLD, is a rare autosomal recessive genetic disorder of copper metabolism, which causes copper to accumulate in body tissues. In this study, rats fed with copper-laden diet are used to render the clinical manifestations of WD, and their copper toxicity-induced organ lesions are studied. To investigate metabolic behaviors of 'decoppering' process, penicillamine (PA was used for treating copper-laden rats as this chelating agent could eliminate excess copper through the urine. To date, there has been limited metabolomics study on WD, while metabolic impacts of copper accumulation and PA administration have yet to be established.A combination of 1HNMR spectroscopy and multivariate statistical analysis was applied to examine the metabolic profiles of the urine and blood serum samples collected from the copper-laden rat model of WD with PA treatment.Copper accumulation in the copper-laden rats is associated with increased lactate, creatinine, valine and leucine, as well as decreased levels of glucose and taurine in the blood serum. There were also significant changes in p-hydroxyphenylacetate (p-HPA, creatinine, alpha-ketoglutarate (α-KG, dimethylamine, N-acetylglutamate (NAG, N-acetylglycoprotein (NAC in the urine of these rats. Notably, the changes in p-HPA, glucose, lactate, taurine, valine, leucine, and NAG were found reversed following PA treatment. Nevertheless, there were no changes for dimethylamine, α-KG, and NAC as a result of the treatment. Compared with the controls, the concentrations of hippurate, formate, alanine, and lactate were changed when PA was applied and this is probably due to its side effect. A tool named SMPDB (Small Molecule Pathway Database is introduced to identify the metabolic pathway influenced by the copper-laden diet.The study has shown the potential application of NMR-based metabolomic analysis in providing further insights into the molecular

  1. Analysis of connection element classes and locations and of some structural requirements for the mounting of different superstructure types on transport vehicles

    Directory of Open Access Journals (Sweden)

    Zoran Đ. Majkić


    Full Text Available The paper presents the basic requirements for transport vehicles. A special request regarding the adaptation of transport vehicles for the transport of various types of cargo was taken into consideration. Superstructures and the situation arising after mounting superstructures on wheeled transport vehicles were analyzed and the following was described: console coupling, stirrups, simplex elastic coupling, two-way elastic and rigid connection elements. Vehicle torsional elasticity is provided by a proper choice of the type of connection between the superstructure and the vehicle chassis. Applying the instructions of vehicle manufacturers for using appropriate connections between the truck superstructure and the vehicle chassis provides positive torsional elasticity of the vehicle. The paper gives the general recommendations of the Volvo, Mercedes and Renault transport vehicle producers for the use of particular connection types of locations as well as structural requirements for the mounting of concrete mixers, tippers and truck tanks on their vehicles. Introduction Achieving a high level of transport effectiveness depends on a number of factors. One of the most important ones is the possibility to increase the payload share in the gross vehicle weight. This share depends on the net vehicle weight, a method of coupling the truck superstructure with the chassis frame as well as on the truck superstructure construction. Realization of this requirement is of significant importance, particularly for large business systems since it results in the reduction of number of necessary vehicles, more economic fleet maintenance and the fleet capacity increase. It is also relatively easy to adapt the vehicle for the transportation of other loads, depending on user's current needs. The adaptation is correctly performed if manufacturer's recommendations are followed during the mounting of the superstructure on the chassis. This paper gives the analysis of the

  2. Superstructure formation and the structural phase diagram of YBasub>2sub>Cu>3sub>O>6sub>+x>

    DEFF Research Database (Denmark)

    Andersen, N.H.; Zimmermann, M. von; Frello, T.


    of the 2D ASYNNNI lattice gas model to include Coulomb interactions between oxygen atoms on chains that are 2a apart, we account for the observed structural phases, and confirm that the superstructures freeze into finite size domains at low temperatures. (C) 1999 Elsevier Science B.V. All rights reserved....

  3. Ag on Ge(111): 2D x-ray structure analysis of the #sq root#3 x #sq root#3 superstructure

    DEFF Research Database (Denmark)

    Dornisch, D.; Moritz, W.; Schulz, H.;


    We have studied the Ag/Ge(111) square-root 3 x square-root 3 superstructure by grazing-incidence X-ray diffraction. In our structural analysis we find striking similarities to the geometry of Au on Si(111). The Ag atoms form trimer clusters with an Ag-Ag distance of 2.94 +/- 0.04 angstrom...

  4. Ultrasensitive SERS detection of VEGF based on a self-assembled Ag ornamented-AU pyramid superstructure. (United States)

    Zhao, Sen; Ma, Wei; Xu, Liguang; Wu, Xiaoling; Kuang, Hua; Wang, Libing; Xu, Chuanlai


    For the first time, we demonstrated the fabrication of silver nanoparticle ornamented-gold nanoparticle pyramids (Ag-Au Pys) using an aptamer-based self-assembly process and investigated their surface-enhanced Raman scattering (SERS) properties in the detection of vascular endothelial growth factor (VEGF). Under optimized conditions, the SERS signal was negatively related to VEGF concentration over the range 0.01-1.0 fM and the limit of detection (LOD) was as low as 22.6 aM. The matrix effect and the specificity of this developed method were further examined, and the results showed that the superstructure sensor was ultrasensitive and highly selective. This developed aptamer-based SERS detection method suggests that it may be a promising strategy for a variety of sensing applications.

  5. Hierarchical assembly of inorganic nanostructure building blocks to octahedral superstructures-a true template-free self-assembly

    Energy Technology Data Exchange (ETDEWEB)

    Kuchibhatla, Satyanarayana V N T [Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, FL-32816 (United States); Karakoti, Ajay S [Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, FL-32816 (United States); Seal, Sudipta [Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, FL-32816 (United States)


    A room temperature, template-free, wet chemical synthesis of ceria nanoparticles and their long term ageing characteristics are reported. High resolution transmission electron microscopy and UV-visible spectroscopy techniques are used to observe the variation in size, structure and oxidation state, respectively as a function of time. The morphology variation and the hierarchical assembly (octahedral superstructure) of nanostructures are imputed to the inherent structural aspects of cerium oxide. It is hypothesized that the 3-5 nm individual building blocks will undergo an intra-agglomerate re-orientation to attain the low energy configuration. This communication also emphasizes the need for long term ageing studies of nanomaterials in various solvents for multiple functionalities.

  6. [A new virus of rabbit. III. Study on morphological superstructure and antigenicity of rabbit hemorrhagic disease virus (RHDV)]. (United States)

    Zhao, L; Li, T; Song, B; Sun, F


    In the spring 1986, an acute infectious disease occurred in Wuhan Second Producing Medical Manufactory, and the rabbit almost died. We tested the mortal symptom and confirmed rabbit Hemorrhagic Disease (RHD) as same as Huang Yinyao report. Hubei Traditional Chinese Medicine Institute appear this RHD also. After we purified virus of above two source by low speed, high speed and sucrose density gradient centrifugation, they can react with antiserum of RHDV from Nanjing Agricultural University in agar gel immunodiffusion tests. These results proved that they belong to the same serotype. Data indicate RHDV have difference morphological superstructure, viral polypeptides and especially RHDV can't react with antiserum of standard Parvovirus of rabbit and so on, so we suggest RHDV is a new virus.

  7. Helical superstructure of continuum graphene cone uncovered by TEM analysis of herringbone-striped pattern in graphitic whiskers (United States)

    Saito, Yukie; Nishio-Hamane, Daisuke


    Cone-shaped graphitic whiskers (CGWs) are a form of pyrolytic carbon, consisting of conically stacked hexagonal carbon layers with an apex angle of ~135-140°. Under transmission electron microscopy (TEM), CGWs often exhibit herringbone-striped patterns. Bright-field (BF) and dark-field (DF) TEM images indicated that the stripes are due to periodical appearance of a strong inter-planar reflection, which is consistent with helical rotation of layers with stepwise "layer overlap". High-resolution TEM revealed that the period was ~14-15 layers. The relationship between apex angle and stripe periodicity of CGWs could be consistently explained in terms of a helical superstructure of tightly coiled continuous graphene cone.

  8. C60 superstructure and carbide formation on the Al-terminated Al9Co2(001 ) surface (United States)

    Ledieu, J.; Gaudry, É.; de Weerd, M.-C.; Gille, P.; Diehl, R. D.; Fournée, V.


    We report the formation of an ordered C60 monolayer on the Al9Co2 (001) surface using scanning tunneling microscopy (STM), low-energy electron diffraction (LEED), x-ray and ultraviolet photoelectron spectroscopy (XPS/UPS), and ab initio calculations. Dosing fullerenes at 300 K results in a disordered overlayer. However, the adsorption of C60 with the sample held between 573-673 K leads to a [4, -2 ∣1 ,3 ] phase. The growth of C60 proceeds with the formation of two domains which are mirror symmetric with respect to the [100] direction. Within each domain, the superstructure unit cell contains six molecules and this implies an area per fullerene equal to 91 Å2. The molecules exhibit two types of contrast (bright and dim) which are bias dependent. The adsorption energies and preferred molecular configuration at several possible adsorption sites have been determined theoretically. These calculations lead to a possible scheme describing the configuration of each C60 in the observed superstructure. Several defects (vacancies, protrusions,…) and domain boundaries observed in the film are also discussed. If the sample temperature is higher than 693 K when dosing, impinging C60 molecules dissociate at the surface, hence leading to the formation of a carbide film as observed by STM and LEED measurements. The formation of Al4C3 domains and the molecular dissociation are confirmed by XPS/UPS measurements acquired at different stages of the experiment. The cluster substructure present at the Al9Co2 (001) surface dictates the carbide domain orientations.

  9. Structures of the ZrZn22 family: suprapolyhedral nanoclusters, methods of self-assembly and superstructural ordering. (United States)

    Ilyushin, G D; Blatov, V A


    A combinatorial topological analysis is carried out by means of the program package TOPOS4.0 [Blatov (2006), IUCr Comput. Commun. Newsl. 7, 4-38] and the matrix self-assembly is modeled for crystal structures of the ZrZn22 family (space group Fd3m, Pearson code cF184), including the compounds with superstructural ordering. A number of strict rules are proposed to model the crystal structures of intermetallics as a network of cluster precursors. According to these rules the self-assembly of the ZrZn22-like structures was considered within the hierarchical scheme: primary polyhedral cluster --> zero-dimensional nanocluster precursor --> one-dimensional primary chain --> two-dimensional microlayer --> three-dimensional microframework (three-dimensional supraprecursor). The suprapolyhedral cluster precursor AB2X37 of diameter approximately 12 A and volume approximately 350 A3 consists of three polyhedra (one AX16 of the 43m point symmetry and two regular icosahedra BX12 of the 3m point symmetry); the packing of the clusters determines the translations in the resulting crystal structure. A novel topological type of the two-dimensional crystal-forming 4,4-coordinated binodal net AB2, with the Schläfli symbols 3636 and 3366 for nodes A and B, is discovered. It is shown that the ZrZn22 superstructures are formed by substituting some atoms in the cluster precursors. Computer analysis of the CRYSTMET and ICSD databases shows that the cluster AB2X37 occurs in 111 intermetallics belonging to 28 structure types.

  10. A mesoscopic formalism for simulating particle-laden flows with applications in energy conversion processes (United States)

    Capecelatro, Jesse Samuel

    The non-linear and multiscale nature of turbulent flows is further complicated in the presence of inertial particles. Intimate coupling between the phases may lead to a high degree of spatial segregation that reorganizes the structure of the underlying turbulence. The wide range of relevant length and timescales associated with fluid-particle systems poses significant challenges in understanding and predicting their behavior. In recent years, the advent of petascale computing has enabled the direct numerical simulation (DNS) of large-scale turbulent flows, though DNS of particle-laden flows remains severely limited. This work presents methods to alleviate previous numerical constraints on the computational grid when considering finite-size particles. Volume filtered equations for the carrier phase are derived in detail for variable-density flows in the presence of particles and solved in a highly-scalable Eulerian-Lagrangian framework. The filter introduces a separation in length-scales during the interphase exchange process, where everything smaller than the support of the filtering kernel requires modeling (e.g., surface reactions and drag), and everything larger than the support of the filtering kernel is captured explicitly. To remain computationally tractable, the filtering procedure is solved in two steps, by first transferring the particle information to the nearest neighboring cells, and then making use of an implicit diffusion operation. In ows that exhibit strong spatial segregation in particle concentration, a separation of length scales must be established when extracting Lagrangian statistics. To accomplish this, an adaptive spatial filter is employed on the particle data with an averaging volume that varies with the local particle-phase volume fraction. The filtered Euler-Lagrange formalism is shown to yield highly accurate and physical results for large-scale particle-laden ows from the dilute to dense regime. An analysis of chemically reacting

  11. Early changes in gene expression induced by blue light irradiation of A2E-laden retinal pigment epithelial cells

    DEFF Research Database (Denmark)

    van der Burght, Barbro W; Hansen, Morten; Olsen, Jørgen;


    Purpose:  Accumulation of bisretinoids as lipofuscin in retinal pigment epithelial (RPE) cells is implicated in the pathogenesis of some blinding diseases including age-related macular degeneration (AMD). To identify genes whose expression may change under conditions of bisretinoid accumulation, we...... investigated the differential gene expression in RPE cells that had accumulated the lipofuscin fluorophore A2E and were exposed to blue light (430 nm). Methods:  A2E-laden RPE cells were exposed to blue light (A2E/430 nm) at various time intervals. Cell death was quantified using Dead Red staining, and RNA...... levels for the entire genome was determined using DNA microarrays (Affymetrix GeneChip Human Genome 2.0 Plus). Array results for selected genes were confirmed by real-time reverse-transcriptase polymerase chain reaction. Results:  Principal component analysis revealed that the A2E-laden RPE cells...

  12. An Innovative Collagen-Based Cell-Printing Method for Obtaining Human Adipose Stem Cell-Laden Structures Consisting of Core-Sheath Structures for Tissue Engineering. (United States)

    Yeo, MyungGu; Lee, Ji-Seon; Chun, Wook; Kim, Geun Hyung


    Three-dimensional (3D) cell printing processes have been used widely in various tissue engineering applications due to the efficient embedding of living cells in appropriately designed micro- or macro-structures. However, there are several issues to overcome, such as the limited choice of bioinks and tailor-made fabricating strategies. Here, we suggest a new, innovative cell-printing process, supplemented with a core-sheath nozzle and an aerosol cross-linking method, to obtain multilayered cell-laden mesh structure and a newly considered collagen-based cell-laden bioink. To obtain a mechanically and biologically enhanced cell-laden structure, we used collagen-bioink in the core region, and also used pure alginate in the sheath region to protect the cells in the collagen during the printing and cross-linking process and support the 3D cell-laden mesh structure. To achieve the most appropriate conditions for fabricating cell-embedded cylindrical core-sheath struts, various processing conditions, including weight fractions of the cross-linking agent and pneumatic pressure in the core region, were tested. The fabricated 3D MG63-laden mesh structure showed significantly higher cell viability (92 ± 3%) compared with that (83 ± 4%) of the control, obtained using a general alginate-based cell-printing process. To expand the feasibility to stem cell-embedded structures, we fabricated a cell-laden mesh structure consisting of core (cell-laden collagen)/sheath (pure alginate) using human adipose stem cells (hASCs). Using the selected processing conditions, we could achieve a stable 3D hASC-laden mesh structure. The fabricated cell-laden 3D core-sheath structure exhibited outstanding cell viability (91%) compared to that (83%) of an alginate-based hASC-laden mesh structure (control), and more efficient hepatogenic differentiations (albumin: ∼ 1.7-fold, TDO-2: ∼ 7.6-fold) were observed versus the control. The selection of collagen-bioink and the new printing strategy

  13. Hydrosoluble, UV-crosslinkable and injectable chitosan for patterned cell-laden microgel and rapid transdermal curing hydrogel in vivo. (United States)

    Li, Baoqiang; Wang, Lei; Xu, Feng; Gang, Xiaomin; Demirci, Utkan; Wei, Daqing; Li, Ying; Feng, Yujie; Jia, Dechang; Zhou, Yu


    Natural and biodegradable chitosan with unique amino groups has found widespread applications in tissue engineering and drug delivery. However, its applications have been limited by the poor solubility of native chitosan in neutral pH solution, which subsequently fails to achieve cell-laden hydrogel at physiological pH. To address this, we incorporated UV crosslinking ability in chitosan, allowing fabrication of patterned cell-laden and rapid transdermal curing hydrogel in vivo. The hydrosoluble, UV crosslinkable and injectable N-methacryloyl chitosan (N-MAC) was synthesized via single-step chemoselective N-acylation reaction, which simultaneously endowed chitosan with well solubility in neutral pH solution, UV crosslinkable ability and injectability. The solubility of N-MAC in neutral pH solution increased 2.21-fold with substitution degree increasing from 10.9% to 28.4%. The N-MAC allowed fabrication of cell-laden microgels with on-demand patterns via photolithography, and the cell viability in N-MAC hydrogel maintained 96.3 ± 1.3% N-MAC allowed rapid transdermal curing hydrogel in vivo within 60s through minimally invasive clinical surgery. Histological analysis revealed that low-dose UV irradiation hardly induced skin injury and acute inflammatory response disappeared after 7 days. N-MAC would allow rapid, robust and cost-effective fabrication of patterned cell-laden polysaccharide microgels with unique amino groups serving as building blocks for tissue engineering and rapid transdermal curing hydrogel in vivo for localized and sustained protein delivery.

  14. Hierarchical super-structure identified by polarized light microscopy, electron microscopy and nanoindentation: Implications for the limits of biological control over the growth mode of abalone sea shells

    Directory of Open Access Journals (Sweden)

    Schneider Andreas S


    Full Text Available Abstract Background Mollusc shells are commonly investigated using high-resolution imaging techniques based on cryo-fixation. Less detailed information is available regarding the light-optical properties. Sea shells of Haliotis pulcherina were embedded for polishing in defined orientations in order to investigate the interface between prismatic calcite and nacreous aragonite by standard materialographic methods. A polished thin section of the interface was prepared with a defined thickness of 60 μm for quantitative birefringence analysis using polarized light and LC-PolScope microscopy. Scanning electron microscopy images were obtained for comparison. In order to study structural-mechanical relationships, nanoindentation experiments were performed. Results Incident light microscopy revealed a super-structure in semi-transparent regions of the polished cross-section under a defined angle. This super-structure is not visible in transmitted birefringence analysis due to the blurred polarization of small nacre platelets and numerous organic interfaces. The relative orientation and homogeneity of calcite prisms was directly identified, some of them with their optical axes exactly normal to the imaging plane. Co-oriented "prism colonies" were identified by polarized light analyses. The nacreous super-structure was also visualized by secondary electron imaging under defined angles. The domains of the super-structure were interpreted to consist of crystallographically aligned platelet stacks. Nanoindentation experiments showed that mechanical properties changed with the same periodicity as the domain size. Conclusions In this study, we have demonstrated that insights into the growth mechanisms of nacre can be obtained by conventional light-optical methods. For example, we observed super-structures formed by co-oriented nacre platelets as previously identified using X-ray Photo-electron Emission Microscopy (X-PEEM [Gilbert et al., Journal of the

  15. Color associations to emotion and emotion-laden words: A collection of norms for stimulus construction and selection. (United States)

    Sutton, Tina M; Altarriba, Jeanette


    Color has the ability to influence a variety of human behaviors, such as object recognition, the identification of facial expressions, and the ability to categorize stimuli as positive or negative. Researchers have started to examine the relationship between emotional words and colors, and the findings have revealed that brightness is often associated with positive emotional words and darkness with negative emotional words (e.g., Meier, Robinson, & Clore, Psychological Science, 15, 82-87, 2004). In addition, words such as anger and failure seem to be inherently associated with the color red (e.g., Kuhbandner & Pekrun). The purpose of the present study was to construct norms for positive and negative emotion and emotion-laden words and their color associations. Participants were asked to provide the first color that came to mind for a set of 160 emotional items. The results revealed that the color RED was most commonly associated with negative emotion and emotion-laden words, whereas YELLOW and WHITE were associated with positive emotion and emotion-laden words, respectively. The present work provides researchers with a large database to aid in stimulus construction and selection.

  16. Cell origami: self-folding of three-dimensional cell-laden microstructures driven by cell traction force.

    Directory of Open Access Journals (Sweden)

    Kaori Kuribayashi-Shigetomi

    Full Text Available This paper describes a method of generating three-dimensional (3D cell-laden microstructures by applying the principle of origami folding technique and cell traction force (CTF. We harness the CTF as a biological driving force to fold the microstructures. Cells stretch and adhere across multiple microplates. Upon detaching the microplates from a substrate, CTF causes the plates to lift and fold according to a prescribed pattern. This self-folding technique using cells is highly biocompatible and does not involve special material requirements for the microplates and hinges to induce folding. We successfully produced various 3D cell-laden microstructures by just changing the geometry of the patterned 2D plates. We also achieved mass-production of the 3D cell-laden microstructures without causing damage to the cells. We believe that our methods will be useful for biotechnology applications that require analysis of cells in 3D configurations and for self-assembly of cell-based micro-medical devices.

  17. Cell Origami: Self-Folding of Three-Dimensional Cell-Laden Microstructures Driven by Cell Traction Force (United States)

    Kuribayashi-Shigetomi, Kaori; Onoe, Hiroaki; Takeuchi, Shoji


    This paper describes a method of generating three-dimensional (3D) cell-laden microstructures by applying the principle of origami folding technique and cell traction force (CTF). We harness the CTF as a biological driving force to fold the microstructures. Cells stretch and adhere across multiple microplates. Upon detaching the microplates from a substrate, CTF causes the plates to lift and fold according to a prescribed pattern. This self-folding technique using cells is highly biocompatible and does not involve special material requirements for the microplates and hinges to induce folding. We successfully produced various 3D cell-laden microstructures by just changing the geometry of the patterned 2D plates. We also achieved mass-production of the 3D cell-laden microstructures without causing damage to the cells. We believe that our methods will be useful for biotechnology applications that require analysis of cells in 3D configurations and for self-assembly of cell-based micro-medical devices. PMID:23251426

  18. 3D bioprinting of neural stem cell-laden thermoresponsive biodegradable polyurethane hydrogel and potential in central nervous system repair. (United States)

    Hsieh, Fu-Yu; Lin, Hsin-Hua; Hsu, Shan-Hui


    The 3D bioprinting technology serves as a powerful tool for building tissue in the field of tissue engineering. Traditional 3D printing methods involve the use of heat, toxic organic solvents, or toxic photoinitiators for fabrication of synthetic scaffolds. In this study, two thermoresponsive water-based biodegradable polyurethane dispersions (PU1 and PU2) were synthesized which may form gel near 37 °C without any crosslinker. The stiffness of the hydrogel could be easily fine-tuned by the solid content of the dispersion. Neural stem cells (NSCs) were embedded into the polyurethane dispersions before gelation. The dispersions containing NSCs were subsequently printed and maintained at 37 °C. The NSCs in 25-30% PU2 hydrogels (∼680-2400 Pa) had excellent proliferation and differentiation but not in 25-30% PU1 hydrogels. Moreover, NSC-laden 25-30% PU2 hydrogels injected into the zebrafish embryo neural injury model could rescue the function of impaired nervous system. However, NSC-laden 25-30% PU1 hydrogels only showed a minor repair effect in the zebrafish model. In addition, the function of adult zebrafish with traumatic brain injury was rescued after implantation of the 3D-printed NSC-laden 25% PU2 constructs. Therefore, the newly developed 3D bioprinting technique involving NSCs embedded in the thermoresponsive biodegradable polyurethane ink offers new possibilities for future applications of 3D bioprinting in neural tissue engineering.

  19. Large eddy simulation of particle-laden flow in a duct with a 90° bend (United States)

    Njobuenwu, D. O.; Fairweather, M.


    Large eddy simulation (LES) of particle-laden turbulent flow is studied for a square duct with a 90° bend and a radius of curvature of 1.5 times the duct width, and for a Reynolds number based on the bulk flow velocity of 100,000. A Lagrangian particle tracking technique is used to study the motion of particles experiencing drag, shear lift, buoyancy and gravitational forces in the flow. LES predictions capture important physical aspects of these flows known to occur in practice, unlike alternative Reynolds-averaged Navier-Stokes (RANS) approaches, such as flow separation in the boundary layers around the bend entrance on the concave wall of the bend, and around the bend exit on the convex wall. The LES predicted flow and particle statistics are generally in good agreement with both experimental data used for validation purposes and RANS solutions, with r.m.s. fluctuating velocity predictions from the LES in particular being superior to values derived using the RANS technique.

  20. Equilibrium electro-deformation of a surfactant-laden viscous drop (United States)

    Nganguia, Herve; Young, Y.-N.; Vlahovska, Petia M.; Bławzdziewcz, Jerzy; Zhang, J.; Lin, H.


    We theoretically investigate the deformation of a viscous drop covered with non-diffusing insoluble surfactant under a uniform DC electric field. At equilibrium, surfactant immobilizes the spheroidal drop surface and completely suppresses the fluid flow. In this work we focus on the equilibrium electro-deformation of a surfactant-laden drop in the leaky dielectric framework by developing (1) a second-order small-deformation analysis and (2) a spheroidal model for a highly deformed (prolate or oblate) drop. Both models are compared against experimental data and numerical simulation results in the literature. Our analysis shows how the existence of equilibrium spheroidal drop depends on the permittivity ratio, conductivity ratio, surfactant coverage, and the elasticity number. Furthermore, the spheroidal model highlights that differences between surfactant effects, such as tip stretching and surface dilution effects, are greatly amplified at large surfactant coverage and high electric capillary number. These surfactant effects are well captured in the spheroidal model, but cannot be described in the second-order small-deformation theory.

  1. Impact of particle-laden drops: Particle distribution on the substrate. (United States)

    Grishaev, Viktor; Iorio, Carlo Saverio; Dubois, Frank; Amirfazli, A


    The splat morphology after the impact of suspension drops on hydrophilic (glass) and hydrophobic (polycarbonate) substrates was investigated. The suspensions were mixtures of water and spherical hydrophobic particles with diameter of 200μm or 500μm. The impact was studied by side, bottom and angled view images. At Reynolds and Weber numbers in the range 150⩽We⩽750 and 7100⩽Re⩽16,400, the particles distributed in a monolayer on the hydrophilic substrates. It was found that the 200μm particles self-arranged as rings or disks on the hydrophilic substrates. On hydrophobic substrates, many particles were at the air-water interface and 200μm formed a crown-like structure. The current study for impact of particle-laden drops shows that the morphology of splats depends on the substrate wettability, the particle size and impact velocity. We developed correlations for the inner and outer diameter of the particle distribution on the hydrophilic substrates, and for the crown height on hydrophobic substrates. The proposed correlations capture the character of the particle distributions after drop impact that depends on particle volume fraction, the wettability of both particles and the substrate, and the dimensionless numbers such as Reynolds and Weber.

  2. A new statistical model for subgrid dispersion in large eddy simulations of particle-laden flows (United States)

    Muela, Jordi; Lehmkuhl, Oriol; Pérez-Segarra, Carles David; Oliva, Asensi


    Dispersed multiphase turbulent flows are present in many industrial and commercial applications like internal combustion engines, turbofans, dispersion of contaminants, steam turbines, etc. Therefore, there is a clear interest in the development of models and numerical tools capable of performing detailed and reliable simulations about these kind of flows. Large Eddy Simulations offer good accuracy and reliable results together with reasonable computational requirements, making it a really interesting method to develop numerical tools for particle-laden turbulent flows. Nonetheless, in multiphase dispersed flows additional difficulties arises in LES, since the effect of the unresolved scales of the continuous phase over the dispersed phase is lost due to the filtering procedure. In order to solve this issue a model able to reconstruct the subgrid velocity seen by the particles is required. In this work a new model for the reconstruction of the subgrid scale effects over the dispersed phase is presented and assessed. This innovative methodology is based in the reconstruction of statistics via Probability Density Functions (PDFs).

  3. Erosion of a grooved surface caused by impact of particle-laden flow (United States)

    Jung, Sohyun; Yang, Eunjin; Kim, Ho-Young


    Solid erosion can be a life-limiting process for mechanical elements in erosive environments, thus it is of practical importance in many industries such as construction, mining, and coal conversion. Erosion caused by particle-laden flow occurs through diverse mechanisms, such as cutting, plastic deformation, brittle fracture, fatigue and melting, depending on particle velocity, total particle mass and impingement angle. Among a variety of attempts to lessen erosion, here we investigate the effectiveness of millimeter-sized grooves on the surface. By experimentally measuring the erosion rates of smooth and triangular-grooved surfaces under various impingement angles, we find that erosion can be significantly reduced within a finite range of impingement angles. We show that such erosion resistance is attributed to the swirls of air within grooves and the differences in erosive strength of normal and slanted impact. In particular, erosion is mitigated when we increase the effective area under normal impact causing plastic deformation and fracture while decreasing the area under slanted impact that cuts the surface to a large degree. Our quantitative model for the erosion rate of grooved surfaces considering the foregoing effects agrees with the measurement results.

  4. Evaluation of cell viability and functionality in vessel-like bioprintable cell-laden tubular channels. (United States)

    Yu, Yin; Zhang, Yahui; Martin, James A; Ozbolat, Ibrahim T


    Organ printing is a novel concept recently introduced in developing artificial three-dimensional organs to bridge the gap between transplantation needs and organ shortage. One of the major challenges is inclusion of blood-vessellike channels between layers to support cell viability, postprinting functionality in terms of nutrient transport, and waste removal. In this research, we developed a novel and effective method to print tubular channels encapsulating cells in alginate to mimic the natural vascular system. An experimental investigation into the influence on cartilage progenitor cell (CPCs) survival, and the function of printing parameters during and after the printing process were presented. CPC functionality was evaluated by checking tissue-specific genetic marker expression and extracellular matrix production. Our results demonstrated the capability of direct fabrication of cell-laden tubular channels by our newly designed coaxial nozzle assembly and revealed that the bioprinting process could induce quantifiable cell death due to changes in dispensing pressure, coaxial nozzle geometry, and biomaterial concentration. Cells were able to recover during incubation, as well as to undergo differentiation with high-level cartilage-associated gene expression. These findings may not only help optimize our system but also can be applied to biomanufacturing of 3D functional cellular tissue engineering constructs for various organ systems.

  5. Drag reduction in turbulent channel laden with finite-size oblate spheroids (United States)

    Niazi Ardekani, Mehdi; Pedro Costa Collaboration; Wim-Paul Breugem Collaboration; Francesco Picano Collaboration; Luca Brandt Collaboration


    Suspensions of oblate rigid particles in a turbulent plane channel flow are investigated for different values of the particle volume fraction. We perform direct numerical simulations (DNS), using a direct-forcing immersed boundary method to account for the particle-fluid interactions, combined with a soft-sphere collision model and lubrication corrections for short-range particle-particle and particle-wall interactions. We show a clear drag reduction and turbulence attenuation in flows laden with oblate spheroids, both with respect to the single phase turbulent flow and to suspensions of rigid spheres. We explain the drag reduction by the lack of the particle layer at the wall, observed before for spherical particles. In addition, the special shape of the oblate particles creates a tendency to stay parallel to the wall in its vicinity, forming a shield of particles that prevents strong fluctuations in the outer layer to reach the wall and vice versa. Detailed statistics of the fluid and particle phase will be presented at the conference to explain the observed drag reduction. Supported by the European Research Council Grant No. ERC-2013-CoG-616186, TRITOS. The authors acknowledge computer time provided by SNIC (Swedish National Infrastructure for Computing) and the support from the COST Action MP1305: Flowing matter.

  6. Managing the potential risks of using bacteria-laden water in mineral processing to protect freshwater. (United States)

    Liu, Wenying; Moran, Chris J; Vink, Sue


    The minerals industry is being driven to access multiple water sources and increase water reuse to minimize freshwater withdrawal. Bacteria-laden water, such as treated effluent, has been increasingly used as an alternative to freshwater for mineral processing, in particular flotation, where conditions are favorable for bacterial growth. However, the risk posed by bacteria to flotation efficiency is poorly understood. This could be a barrier to the ongoing use of this water source. This study tested the potential of a previously published risk-based approach as a management tool to both assist mine sites in quantifying the risk from bacteria, and finding system-wide cost-effective solutions for risk mitigation. The result shows that the solution of adjusting the flotation chemical regime could only partly control the risk. The second solution of using tailings as an absorbent was shown to be effective in the laboratory in reducing bacterial concentration and thus removing the threat to flotation recovery. The best solution is likely to combine internal and external approaches, that is, inside and outside processing plants. Findings in this study contribute possible methods applicable to managing the risk from water-borne bacteria to plant operations that choose to use bacteria-containing water, when attempting to minimize freshwater use, and avoiding the undesirable consequences of increasing its use.

  7. A collision model for fully-resolved simulations of flows laden with finite-size particles

    CERN Document Server

    Costa, Pedro; Westerweel, Jerry; Breugem, Wim-Paul


    We present a collision model for particle-particle and particle-wall interactions in interface-resolved simulations of particle-laden flows. Three types of inter-particle interactions are taken into account: (1) long- and (2) short-range hydrodynamic interactions, and (3) solid-solid contact. Long-range interactions are incorporated through an efficient and second-order accurate immersed boundary method (IBM). Short-range interactions are also partly reproduced by the IBM. However, since the IBM uses a fixed-grid, a lubrication model is needed for an inter-particle gap width smaller than the grid spacing. The lubrication model is based on asymptotic expansions of analytical solutions for canonical lubrication interactions between spheres in the Stokes regime. Roughness effects are incorporated by making the lubrication correction independent of the gap width for gap widths smaller than $\\sim 1\\%$ of the particle radius. This correction is applied until the particles reach solid-solid contact. To model solid-s...

  8. Coupling Discrete and Continuum Mechanics in Low Concentration, Particle-Laden Flows (United States)

    Boyle, Paul; Houchens, Brent; Kim, Albert


    The study of particle-laden flow plays a critical role in pressure-driven membrane filtration such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO). Hydrodynamic and inter-particle interactions, coupled to the ambient crossflow field, are well documented in literature. Transport of particles is originated due to Brownian and shear-induced diffusion, and convection due to the axial crossflow and transverse permeate flow. These effects are modeled using Hydrodynamic Force Bias Monte Carlo (HFBMC) simulations to predict the deposition of the particles on the membrane surface. In addition, the particles in the simulation are also subject to electrostatic double layer repulsion and van der Waals attraction both between particles and between the particles and membrane surfaces. In conjunction with the hydrodynamics, the change in particle potential determines the transition probability that a proposed, random move of a particle will be accepted. In the current study, these discrete particle effects at the microscopic level are coupled to the continuum flow via an apparent local viscosity, yielding a quasi-steady-state velocity profile. This velocity profile is dynamically updated in order to refine the hydrodynamic interactions. The resulting simulation predicts the formation of a cake layer of deposited interacting particles on the membrane surface.

  9. Bioprinting three-dimensional cell-laden tissue constructs with controllable degradation (United States)

    Wu, Zhengjie; Su, Xin; Xu, Yuanyuan; Kong, Bin; Sun, Wei; Mi, Shengli


    Alginate hydrogel is a popular biologically inert material that is widely used in 3D bioprinting, especially in extrusion-based printing. However, the printed cells in this hydrogel could not degrade the surrounding alginate gel matrix, causing them to remain in a poorly proliferating and non-differentiating state. Here, we report a novel study of the 3D printing of human corneal epithelial cells (HCECs)/collagen/gelatin/alginate hydrogel incubated with a medium containing sodium citrate to obtain degradation-controllable cell-laden tissue constructs. The 3D-printed hydrogel network with interconnected channels and a macroporous structure was stable and achieved high cell viability (over 90%). By altering the mole ratio of sodium citrate/sodium alginate, the degradation time of the bioprinting constructs can be controlled. Cell proliferation and specific marker protein expression results also revealed that with the help of sodium citrate degradation, the printed HCECs showed a higher proliferation rate and greater cytokeratin 3(CK3) expression, indicating that this newly developed method may help to improve the alginate bioink system for the application of 3D bioprinting in tissue engineering. PMID:27091175

  10. Michael Jackson, Bin Laden and I: functions of positive and negative, public and private flashbulb memories. (United States)

    Demiray, Burcu; Freund, Alexandra M


    This study examined the perceived psychosocial functions of flashbulb memories: It compared positive and negative public flashbulb memories (positive: Bin Laden's death, negative: Michael Jackson's death) with private ones (positive: pregnancy, negative: death of a loved one). A sample of n = 389 young and n = 176 middle-aged adults answered canonical category questions used to identify flashbulb memories and rated the personal significance, the psychological temporal distance, and the functions of each memory (i.e., self-continuity, social-boding, directive functions). Hierarchical regressions showed that, in general, private memories were rated more functional than public memories. Positive and negative private memories were comparable in self-continuity and directionality, but the positive private memory more strongly served social functions. In line with the positivity bias in autobiographical memory, positive flashbulb memories felt psychologically closer than negative ones. Finally, middle-aged adults rated their memories as less functional regarding self-continuity and social-bonding than young adults. Results are discussed regarding the tripartite model of autobiographical memory functions.

  11. Velocity profile of turbulent sediment-laden flows in open-channels

    Institute of Scientific and Technical Information of China (English)

    Deyu Zhong n; Lei Zhang; Baosheng Wu; Yongqiang Wang


    In this paper, a study was carried out on the velocity profile of sediment-laden flows in open channels using a two-phase mixture model for two-phase flows. The governing equations for water-sediment mixtures were derived based on the two-fluid equations for solid–liquid two-phase flows. The drift velocity, a key variable involved in the two-phase mixture equations, was derived from the equation of momentum conservation for the solid phase. The drift velocity shows that the inertia of flow, particle turbulence, and collisions effect contribute to the dispersion of the sediment particles in turbulent flows. Using the two-phase mixture equation, the vertical velocity profile of open channel flows was obtained. Further analysis indicated that the distribution of the velocity over depth of water-sediment mixtures, composed of two different phases, is significantly affected by the turbulence of water-sediment mixtures and the density stratification. However, the velocity distribution is also affected by other factors including collisions between particles and particle turbulence as a basic feature of two-phase flows where interphase interactions inevitably mark their influence on the velocity distribution. Comparisons of this approach with observations for a wide range of experimental conditions are presented in this paper, which show that this approach agrees well with the experiments.

  12. Phenomenology of break-up modes in contact free externally heated nanoparticle laden fuel droplets (United States)

    Pathak, Binita; Basu, Saptarshi


    We study thermally induced atomization modes in contact free (acoustically levitated) nanoparticle laden fuel droplets. The initial droplet size, external heat supplied, and suspended particle concentration (wt. %) in droplets govern the stability criterion which ultimately determines the dominant mode of atomization. Pure fuel droplets exhibit two dominant modes of breakup namely primary and secondary. Primary modes are rather sporadic and normally do not involve shape oscillations. Secondary atomization however leads to severe shape deformations and catastrophic intense breakup of the droplets. The dominance of these modes has been quantified based on the external heat flux, dynamic variation of surface tension, acoustic pressure, and droplet size. Addition of particles alters the regimes of the primary and secondary atomization and introduces bubble induced boiling and bursting. We analyze this new mode of atomization and estimate the time scale of bubble growth up to the point of bursting using energy balance to determine the criterion suitable for parent droplet rupture. All the three different modes of breakup have been well identified in a regime map determined in terms of Weber number and the heat utilization rate which is defined as the energy utilized for transient heating, vaporization, and boiling in droplets.

  13. Microfabrication of proangiogenic cell-laden alginate-g-pyrrole hydrogels. (United States)

    DeVolder, Ross J; Zill, Andrew T; Jeong, Jae H; Kong, Hyunjoon


    Cells have been extensively studied for their uses in various therapies because of their capacities to produce therapeutic proteins and recreate new tissues. It has often been suggested that the efficacy of cell therapies can greatly be improved through the ability to localize and regulate cellular activities at a transplantation site; however, the technologies for this control are lacking. Therefore, this study reports a cell-Laden hydrogel patch engineered to support the proliferation and angiogenic growth factor expression of cells adhered to their surfaces, and to further promote neovascularization. Hydrogels consisting of alginate chemically linked with pyrrole units, termed alginate-g-pyrrole, were prepared through an oxidative cross-linking reaction between pyrrole units. Fibroblasts adhered to the alginate-g-pyrrole hydrogels, and exhibited increased proliferation and overall vascular endothelial growth factor (VEGF) expression, compared to those on pyrrole-free hydrogels. Furthermore, the alginate-g-pyrrole hydrogel surfaces were modified to present microposts, subsequently increasing the amount of pyrrole units on their surfaces. Cells adhered to the microfabricated gel surfaces exhibited increased proliferation and overall VEGF expression proportional to the density of the microposts. The resulting micropatterned alginate-g-pyrrole hydrogels exhibited increases in the size and density of mature blood vessels when implanted on chick chorioallantoic membranes (CAMs). The hydrogel system developed in this study will be broadly useful for improving the efficacy of a wide array of cell-based wound healing and tissue regenerative therapies.

  14. Dioxin-Laden residual streams from thermal and metallurgical processes: inventory and management

    Energy Technology Data Exchange (ETDEWEB)

    Buekens, A.; Schroyen, K.; Segers, P.


    On behalf of Aminable, the Planning Division of the Flemish Administration for the Envrioment, Nature, Land & Water Management, an inventory was prepared of all dixin-laden residual streams arising in Flanders in thermal and industrial plant & processes, more in particular in the following 7 major sectors of activity: 1) metallurgy: 2) cement, glass, and ceramic industry; 3) power plant; 4) oil refineries; 5) industrial boilers and domestic heating; 6) vinyl chloride manufacturing; and 7) waste incineration. It was expected to gather in this scope all major flows of dioxin containing residues in Flanders, with only three exceptions, namely those arising form (a) cold sources, (b) various historical sinks and (c) import of materials. Others tasks included: studying the tractories taken by the various residual stream, evaluating the risk associated with their disposal, indicating a Best Available Technology for their treatment, identify further issues of concern, and finally, suggest measures for management, whether based on dedicated new legislation, further specification or completion of existing rules, or more active implementation of monitoring, inspection, etc. within the current legal framework. (Author) 7 refs.

  15. Layer by layer three-dimensional tissue epitaxy by cell-laden hydrogel droplets. (United States)

    Moon, SangJun; Hasan, Syed K; Song, Young S; Xu, Feng; Keles, Hasan Onur; Manzur, Fahim; Mikkilineni, Sohan; Hong, Jong Wook; Nagatomi, Jiro; Haeggstrom, Edward; Khademhosseini, Ali; Demirci, Utkan


    The ability to bioengineer three-dimensional (3D) tissues is a potentially powerful approach to treat diverse diseases such as cancer, loss of tissue function, or organ failure. Traditional tissue engineering methods, however, face challenges in fabricating 3D tissue constructs that resemble the native tissue microvasculature and microarchitectures. We have developed a bioprinter that can be used to print 3D patches of smooth muscle cells (5 mm x 5 mm x 81 microm) encapsulated within collagen. Current inkjet printing systems suffer from loss of cell viability and clogging. To overcome these limitations, we developed a system that uses mechanical valves to print high viscosity hydrogel precursors containing cells. The bioprinting platform that we developed enables (i) printing of multilayered 3D cell-laden hydrogel structures (16.2 microm thick per layer) with controlled spatial resolution (proximal axis: 18.0 +/- 7.0 microm and distal axis: 0.5 +/- 4.9 microm), (ii) high-throughput droplet generation (1 s per layer, 160 droplets/s), (iii) cell seeding uniformity (26 +/- 2 cells/mm(2) at 1 million cells/mL, 122 +/- 20 cells/mm(2) at 5 million cells/mL, and 216 +/- 38 cells/mm(2) at 10 million cells/mL), and (iv) long-term viability in culture (>90%, 14 days). This platform to print 3D tissue constructs may be beneficial for regenerative medicine applications by enabling the fabrication of printed replacement tissues.

  16. Effects of basin bottom slope on jet hydrodynamics and river mouth bar formation (United States)

    Jiménez-Robles, A. M.; Ortega-Sánchez, M.; Losada, M. A.


    River mouth bars are strategic morphological units primarily responsible for the development of entire deltaic systems. This paper addresses the role of receiving basin slope in the hydrodynamics of an exiting sediment-laden turbulent jet and in resulting mouth bar morphodynamics. We use Delft3D, a coupled hydrodynamic and morphodynamic numerical model, along with a theoretical formulation to reproduce the physics of the problem, characterized by a fluvially dominated inlet free of waves and tides. We propose an updated theoretical model with a slope-dependent entrainment coefficient, showing that the rate at which ambient fluid is incorporated into a jet increases with higher basin slopes. Transient results reveal that the magnitude of a basin slope can alter the stability of a jet, favoring the formation of an unstable meandering jet. While a stable jet gives rise to "middle-ground" bars accompanied by diverging channels, a "lunate" mouth bar results from unstable jets. Additional morphodynamic simulations demonstrate that the time required for mouth bar stagnation in its final position increases linearly with the basin slope. In contrast, the distance at which the mouth bar eventually forms decreases until reaching an asymptotic value for slopes higher than 2%. Moreover, the basin slope highly influences sedimentary processes responsible for bar formation: for milder slopes, progradation processes prevail, while in steeper basins aggradation is more relevant. Finally, the minimum relative water depth over a bar crest that forces the flow to bifurcate around a fully developed bar decreases with the basin slope.

  17. TEM and SEM observations of super-structures constructed in organogel systems from a combination of boronic-acid-appended bola-amphiphiles with chiral diols (United States)

    Koumoto, Kazuya; Yamashita, Tadahiro; Kimura, Taro; Luboradzki, Roman; Shinkai, Seiji


    Two bola-amphiphilic α,ω-diboronic acids separated by a (CH2)11 or (CH2)12 group were synthesized. Complexation with chiral diols readily gave new amphiphiles end-capped with the chiral substituents. Some of these acted as good gelators of organic solvents. Transmission electron microscope and scanning electron microscope observations established that a variety of super-structures are created in the organogels, depending on the solvents and the structure of the chiral end-cap groups. In most cases, the fibrous aggregates, the network structure which is the driving-force for gelation, showed a helical higher-order structure reflecting the chirality of the end-cap groups. The results indicate that the combinatorial approach utilizing boronic acid functions and diol compounds is useful in creating a variety of new super-structures in the gel phase.

  18. Giant reversible magnetocaloric effect in flower-like β-Co(OH){sub 2} hierarchical superstructures self-assembled by nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xianguo; Feng, Chao; Xiao, Feng; Jin, Chuangui; Xia, Ailin, E-mail:, E-mail: [Anhui Key Laboratory of Metal Materials and Processing, School of Materials Science and Engineering, Anhui University of Technology, Ma' anshan, PR (China); Or, Siu Wing [Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Sun, Yuping [Center for Engineering Practice and Innovation Education, Anhui University of Technology, Ma' anshan, PR (China)


    A facile hydrothermal strategy is proposed to synthesize flower-like β- Co(OH){sub 2} hierarchical microspherical superstructures with a diameter of 0.5-1.5 µm, which are self-assembled by β - Co(OH){sub 2} nano sheets with the average thickness ranging between 20 and 40 nm. The magnetocaloric effect associated with magnetic phase transitions in Co(OH){sub 2} superstructures has been investigated. A sign change in the magnetocaloric effect is induced by a magnetic field, which is related to a filed-induced transition from the antiferromagnetic to the ferromagnetic state below the Néel temperature. The large reversible magnetic-entropy change –ΔS{sub m} (13.4 J/kg K at 15 K for a field change of 5 T) indicates that flower-like Co(OH){sub 2} superstructures is a potential candidate for application in magnetic refrigeration in the low-temperature range. (author)

  19. Spatial Separation of Charge Carriers in In2O3-x(OH)y Nanocrystal Superstructures for Enhanced Gas-Phase Photocatalytic Activity. (United States)

    He, Le; Wood, Thomas E; Wu, Bo; Dong, Yuchan; Hoch, Laura B; Reyes, Laura M; Wang, Di; Kübel, Christian; Qian, Chenxi; Jia, Jia; Liao, Kristine; O'Brien, Paul G; Sandhel, Amit; Loh, Joel Y Y; Szymanski, Paul; Kherani, Nazir P; Sum, Tze Chien; Mims, Charles A; Ozin, Geoffrey A


    The development of strategies for increasing the lifetime of photoexcited charge carriers in nanostructured metal oxide semiconductors is important for enhancing their photocatalytic activity. Intensive efforts have been made in tailoring the properties of the nanostructured photocatalysts through different ways, mainly including band-structure engineering, doping, catalyst-support interaction, and loading cocatalysts. In liquid-phase photocatalytic dye degradation and water splitting, it was recently found that nanocrystal superstructure based semiconductors exhibited improved spatial separation of photoexcited charge carriers and enhanced photocatalytic performance. Nevertheless, it remains unknown whether this strategy is applicable in gas-phase photocatalysis. Using porous indium oxide nanorods in catalyzing the reverse water-gas shift reaction as a model system, we demonstrate here that assembling semiconductor nanocrystals into superstructures can also promote gas-phase photocatalytic processes. Transient absorption studies prove that the improved activity is a result of prolonged photoexcited charge carrier lifetimes due to the charge transfer within the nanocrystal network comprising the nanorods. Our study reveals that the spatial charge separation within the nanocrystal networks could also benefit gas-phase photocatalysis and sheds light on the design principles of efficient nanocrystal superstructure based photocatalysts.

  20. Conceptual design and scaled experimental validation of an actively damped carbon tie rods support system for the stabilization of future particle collider superstructures. (United States)

    Collette, C; Tshilumba, D; Fueyo-Rosa, L; Romanescu, I


    This paper presents a simple solution to increase the stability of the large superstructures supporting the final electromagnets of future linear particle collider. It consists of active carbon fiber tie rods, fixed at one end on the structure and at the other end to the detector through active tendons. In the first part of the paper, the solution has been tested on a finite element model of one half of the CLIC_ILD final focus structure. With a reasonable design, it is shown numerically that the compliance can be decreased by at least a factor 4, i.e., that the structure is 4 times more robust to technical noise at low frequency. Two additional features of the active rods are that they can also actively damp the structural resonances and realign the superstructures. The second part of the paper presents a successful experimental validation of the concept, applied to a scaled test bench, especially designed to contain the same modal characteristics as the full scale superstructure.

  1. Asphaltene-laden interfaces form soft glassy layers in contraction experiments: a mechanism for coalescence blocking. (United States)

    Pauchard, Vincent; Rane, Jayant P; Banerjee, Sanjoy


    In previous studies, the adsorption kinetics of asphaltenes at the water-oil interface were interpreted utilizing a Langmuir equation of state (EOS) based on droplet expansion experiments.1-3 Long-term adsorption kinetics followed random sequential adsorption (RSA) theory predictions, asymptotically reaching ∼85% limiting surface coverage, which is similar to limiting random 2D close packing of disks. To extend this work beyond this slow adsorption process, we performed rapid contractions and contraction-expansions of asphaltene-laden interfaces using the pendant drop experiment to emulate a Langmuir trough. This simulates the rapid increase in interfacial asphaltene concentration that occurs during coalescence events. For the contraction of droplets aged in asphaltene solutions, deviation from the EOS consistently occurs at a surface pressure value ∼21 mN/m corresponding to a surface coverage ∼80%. At this point droplets lose the shape required for validity of the Laplace-Young equation, indicating solidlike surface behavior. On further contraction wrinkles appear, which disappear when the droplet is held at constant volume. Surface pressure also decreases down to an equilibrium value near that measured for slow adsorption experiments. This behavior appears to be due to a transition to a glassy interface on contraction past the packing limit, followed by relaxation toward equilibrium by desorption at constant volume. This hypothesis is supported by cycling experiments around the close-packed limit where the transition to and from a solidlike state appears to be both fast and reversible, with little hysteresis. Also, the soft glass rheology model of Sollich is shown to capture previously reported shear behavior during adsorption. The results suggest that the mechanism by which asphaltenes stabilize water-in-oil emulsions is by blocking coalescence due to rapid formation of a glassy interface, in turn caused by interfacial asphaltenes rapidly increasing in

  2. Water demand for ecosystem protection in rivers with hyper-concentrated sediment-laden flow

    Institute of Scientific and Technical Information of China (English)

    LUO Huaming; LI Tianhong; NI Jinren; WANG Yudong


    Sediment transport is one of the main concerns in a river system with hyper-concentrated flows. Therefore, the water use for sediment transport must be considered in study on the water demand for river ecosystem. The conventional methods for calculating the Minimum Water Demand for River Ecosystem (MWDRE) are not appropriate for rivers with high sediment concentration. This paper studied the MWDRE in wet season, dry season and the whole year under different water-and-sediment conditions in the Lower Yellow River, which is regarded as a typical river with sediment-laden flows. The characteristics of MWDRE in the river are analyzed. Firstly,the water demand for sediment transport (WDST) is much larger than the demands for other riverine functions, the WDST accounts for the absolute majority of the MWDRE.Secondly, in wet season when the WDST is satisfied, not only most of the annual incoming sediment can be transported downstream, but also the water demands for other river functions can be satisfied automatically, so that the MWDRE in wet season is identical to the WDST. Thirdly, in dry season, when the WDST is satisfied, the water demands for other river functions can also be satisfied, but the low sediment transport efficiency results in significant waste of water resources. According to these characteristics and aiming at decreasing sediment deposition in the riverbed and improving the utilization efficiency of water resources, hydrological engineering works can be used to regulate or control flow and sediment so that the sediment incoming in dry season can be accumulated and be transported downstream intensively and thus efficiently in wet season.

  3. One-step cell lysis suitable for quantitative bacteria detection in inhibitor-laden sands (United States)

    Lim, Hyun Jeong; Choi, Jung-Hyun; Son, Ahjeong


    Complexity and heterogeneity of soils often hinder effective DNA extraction from the soil matrix. In particular, conventional DNA extraction techniques require extensive purification which makes DNA extraction time-consuming and labor-intensive. Other drawbacks include lower recovery yield, degradation, and damage of DNA, which are also caused by intensive purifications during DNA extraction. Therefore a rapid and simple and yet effective DNA pretreatment method is preferred for environmental monitoring and screening. This study has evaluated the feasibility of simple physical pretreatment for effective cell lysis of bacteria in sands. Bead beating method was selected as an effective physical cell lysis method in this study. We examined the capability of this physical lysis for Pseudomonas putida seeded sands without additional chemical purification steps. The lysate from the method was analysed by the quantitative polymerase chain reaction (qPCR) assay and subsequently compared to that by commercial DNA extraction kit. The best lysis condition (treatment with 0.1 mm glass beads at 3000 rpm for 3 minutes) was selected. The qPCR results of bead beating treated samples showed the better performance than that of conventional DNA extraction kit. Moreover, the qPCR assay was performed to the sands laden with qPCR inhibitors (humic acids, clay, and magnesium), which generally present in environmental samples. Further experiments with the sands containing less than 10 μg/g of humic acids and 70% of clay showed successful quantification results of qPCR assay. In conclusion, the bead beating method is useful for simplified DNA extraction prior to qPCR analysis for sand samples of particular composition. It is expected that this approach will be beneficial for environmental in-situ analysis or immediate pre-screening. It also provides the groundwork for future studies with real soil samples that have various physico-chemical properties.

  4. A Penalty Method to Model Particle Interactions in DNA-laden Flows

    Energy Technology Data Exchange (ETDEWEB)

    Trebotich, D; Miller, G H; Bybee, M D


    We present a hybrid fluid-particle algorithm to simulate flow and transport of DNA-laden fluids in microdevices. Relevant length scales in microfluidic systems range from characteristic channel sizes of millimeters to micron scale geometric variation (e.g., post arrays) to 10 nanometers for the length of a single rod in a bead-rod polymer representation of a biological material such as DNA. The method is based on a previous fluid-particle algorithm in which long molecules are represented as a chain of connected rods, but in which the physically unrealistic behavior of rod crossing occurred. We have extended this algorithm to include screened Coulombic forces between particles by implementing a Debye-Hueckel potential acting between rods. In the method an unsteady incompressible Newtonian fluid is discretized with a second-order finite difference method in the interior of the Cartesian grid domain; an embedded boundary volume-of-fluid formulation is used near boundaries. The bead-rod polymer model is fully coupled to the solvent through body forces representing hydrodynamic drag and stochastic thermal fluctuations. While intrapolymer interactions are modeled by a soft potential, polymer-structure interactions are treated as perfectly elastic collisions. We demonstrate this method on flow and transport of a polymer through a post array microchannel in 2D where the polymer incorporates more realistic physical parameters of DNA, and compare to previous simulations where rods are allowed to cross. We also show that the method is capable of simulating 3D flow in a packed bed micro-column.

  5. Regulatory implications of using constructed wetlands to treat selenium-laden wastewater. (United States)

    Lemly, A Dennis; Ohlendorf, Harry M


    The practice of using constructed wetlands to treat selenium-laden wastewater is gaining popularity in the United States and elsewhere. However, proponents of treatment wetlands often overlook important ecological liabilities and regulatory implications when developing new methods and applications. Their research studies typically seek to answer a basic performance question--are treatment wetlands effective in improving water quality--rather than answering an implicit safety question-are they hazardous to wildlife. Nevertheless, wetland owners are responsible for both the operational performance of treatment wetlands and the health of animals that use them. This is true even if wetlands were not created with the intent of providing wildlife habitat; the owner is still legally responsible for toxic hazards. If poisoning of fish and wildlife occurs, the owner can be prosecuted under a variety of federal and state laws, for example, the Migratory Bird Treaty Act and the Endangered Species Act. In considering this type of treatment technology it is important to document the selenium content of the wastewater, understand how it cycles and accumulates in the environment, and evaluate the threat it may pose to fish and wildlife before deciding whether or not to proceed with construction. Many of the potential hazards may not be obvious to project planners, particularly if there is no expressed intention for the wetland to provide wildlife habitat. Ecological risk assessment provides an approach to characterizing proposed treatment wetlands with respect to wildlife use, selenium contamination, and possible biological impacts. Proper application of this approach can reveal potential problems and the associated liabilities, and form the basis for selection of an environmentally sound treatment option.

  6. Automatic segmentation of tumor-laden lung volumes from the LIDC database (United States)

    O'Dell, Walter G.


    The segmentation of the lung parenchyma is often a critical pre-processing step prior to application of computer-aided detection of lung nodules. Segmentation of the lung volume can dramatically decrease computation time and reduce the number of false positive detections by excluding from consideration extra-pulmonary tissue. However, while many algorithms are capable of adequately segmenting the healthy lung, none have been demonstrated to work reliably well on tumor-laden lungs. Of particular challenge is to preserve tumorous masses attached to the chest wall, mediastinum or major vessels. In this role, lung volume segmentation comprises an important computational step that can adversely affect the performance of the overall CAD algorithm. An automated lung volume segmentation algorithm has been developed with the goals to maximally exclude extra-pulmonary tissue while retaining all true nodules. The algorithm comprises a series of tasks including intensity thresholding, 2-D and 3-D morphological operations, 2-D and 3-D floodfilling, and snake-based clipping of nodules attached to the chest wall. It features the ability to (1) exclude trachea and bowels, (2) snip large attached nodules using snakes, (3) snip small attached nodules using dilation, (4) preserve large masses fully internal to lung volume, (5) account for basal aspects of the lung where in a 2-D slice the lower sections appear to be disconnected from main lung, and (6) achieve separation of the right and left hemi-lungs. The algorithm was developed and trained to on the first 100 datasets of the LIDC image database.

  7. Fabrication of 3D cell-laden hydrogel microstructures through photo-mold patterning. (United States)

    Occhetta, P; Sadr, N; Piraino, F; Redaelli, A; Moretti, M; Rasponi, M


    Native tissues are characterized by spatially organized three-dimensional (3D) microscaled units which functionally define cells-cells and cells-extracellular matrix interactions. The ability to engineer biomimetic constructs mimicking these 3D microarchitectures is subject to the control over cell distribution and organization. In the present study we introduce a novel protocol to generate 3D cell laden hydrogel micropatterns with defined size and shape. The method, named photo-mold patterning (PMP), combines hydrogel micromolding within polydimethylsiloxane (PDMS) stamps and photopolymerization through a recently introduced biocompatible ultraviolet (UVA) activated photoinitiator (VA-086). Exploiting PDMS micromolds as geometrical constraints for two methacrylated prepolymers (polyethylene glycol diacrylate and gelatin methacrylate), micrometrically resolved structures were obtained within a 3 min exposure to a low cost and commercially available UVA LED. The PMP was validated both on a continuous cell line (human umbilical vein endothelial cells expressing green fluorescent protein, HUVEC GFP) and on primary human bone marrow stromal cells (BMSCs). HUVEC GFP and BMSCs were exposed to 1.5% w/v VA-086 and UVA light (1 W, 385 nm, distance from sample = 5 cm). Photocrosslinking conditions applied during the PMP did not negatively affect cells viability or specific metabolic activity. Quantitative analyses demonstrated the potentiality of PMP to uniformly embed viable cells within 3D microgels, creating biocompatible and favorable environments for cell proliferation and spreading during a seven days' culture. PMP can thus be considered as a promising and cost effective tool for designing spatially accurate in vitro models and, in perspective, functional constructs.

  8. Three-dimensional bioprinting of complex cell laden alginate hydrogel structures. (United States)

    Tabriz, Atabak Ghanizadeh; Hermida, Miguel A; Leslie, Nicholas R; Shu, Wenmiao


    Different bioprinting techniques have been used to produce cell-laden alginate hydrogel structures, however these approaches have been limited to 2D or simple three-dimension (3D) structures. In this study, a new extrusion based bioprinting technique was developed to produce more complex alginate hydrogel structures. This was achieved by dividing the alginate hydrogel cross-linking process into three stages: primary calcium ion cross-linking for printability of the gel, secondary calcium cross-linking for rigidity of the alginate hydrogel immediately after printing and tertiary barium ion cross-linking for long-term stability of the alginate hydrogel in culture medium. Simple 3D structures including tubes were first printed to ensure the feasibility of the bioprinting technique and then complex 3D structures such as branched vascular structures were successfully printed. The static stiffness of the alginate hydrogel after printing was 20.18 ± 1.62 KPa which was rigid enough to sustain the integrity of the complex 3D alginate hydrogel structure during the printing. The addition of 60 mM barium chloride was found to significantly extend the stability of the cross-linked alginate hydrogel from 3 d to beyond 11 d without compromising the cellular viability. The results based on cell bioprinting suggested that viability of U87-MG cells was 93 ± 0.9% immediately after bioprinting and cell viability maintained above 88% ± 4.3% in the alginate hydrogel over the period of 11 d.

  9. Proposal for the award of an industrial services contract for civil engineering superstructure and internal construction building work

    CERN Document Server


    This document concerns the award of an Industrial Services contract for civil engineering superstructure and internal construction building work. Following a market survey carried out among 112 firms in fifteen Member States, a call for tenders (IT-2546/ST/Rev.) was sent on 12 April 2001 to eleven consortia, four consisting of four firms, three consisting of three firms and four consisting of two firms, in seven Member States. By the closing date, CERN had received tenders from eight consortia in six Member States. The Finance Committee is invited to agree to the negotiation of a contract with the consortium SPIE CITRA SUD-EST(FR)-ANTIRUST TECHNOLOGY (GR), the lowest bidder, for an initial period of three years from 1 January 2002 for an amount not exceeding 15 375 000 Swiss francs, not subject to revision. The contract will include options for two one-year extensions beyond the initial three-year period. The consortium has indicated the following distribution by country of the contract value covered by this ...

  10. Improved charge transport and injection in a meso-superstructured solar cell by a tractable pre-spin-coating process. (United States)

    Li, Nan; Li, Haoyuan; Li, Yu; Wang, Shufeng; Wang, Liduo


    In meso-superstructured solar cells (MSSCs), the state-of-the-art perovskite acts as both the light harvester and electron transporter due to its ambipolar properties. The inefficient pore filling and infiltration of perovskite directly affect the continuous distribution of perovskite in mesoporous Al2O3, resulting in discontinuous carrier transport in the mesoporous structure and insufficient electron injection to the compact TiO2 layer. Herein, we introduce a simple pre-spin-coating process to improve the infiltration and pore filling of perovskite, which results in higher light absorption and enhanced electron injection, as seen in UV-vis spectra and photoluminescence (PL) spectra, respectively. We first apply time of flight (TOF) experiments to characterize charge transport in MSSCs, and the results reveal that more continuous charge transport pathways are formed with the pre-spin-coating process. This effective method, with ease of processing, demonstrates obviously improved photocurrents, reaching an efficiency as high as 14%, and promotes the application of lead halide perovskite materials in the photovoltaics field.

  11. A second-order accurate immersed boundary-lattice Boltzmann method for particle-laden flows (United States)

    Zhou, Qiang; Fan, Liang-Shih


    A new immersed boundary-lattice Boltzmann method (IB-LBM) is presented for fully resolved simulations of incompressible viscous flows laden with rigid particles. The immersed boundary method (IBM) recently developed by Breugem (2012) [19] is adopted in the present method, development including the retraction technique, the multi-direct forcing method and the direct account of the inertia of the fluid contained within the particles. The present IB-LBM is, however, formulated with further improvement with the implementation of the high-order Runge-Kutta schemes in the coupled fluid-particle interaction. The major challenge to implement high-order Runge-Kutta schemes in the LBM is that the flow information such as density and velocity cannot be directly obtained at a fractional time step from the LBM since the LBM only provides the flow information at an integer time step. This challenge can be, however, overcome as given in the present IB-LBM by extrapolating the flow field around particles from the known flow field at the previous integer time step. The newly calculated fluid-particle interactions from the previous fractional time steps of the current integer time step are also accounted for in the extrapolation. The IB-LBM with high-order Runge-Kutta schemes developed in this study is validated by several benchmark applications. It is demonstrated, for the first time, that the IB-LBM has the capacity to resolve the translational and rotational motion of particles with the second-order accuracy. The optimal retraction distances for spheres and tubes that help the method achieve the second-order accuracy are found to be around 0.30 and -0.47 times of the lattice spacing, respectively. Simulations of the Stokes flow through a simple cubic lattice of rotational spheres indicate that the lift force produced by the Magnus effect can be very significant in view of the magnitude of the drag force when the practical rotating speed of the spheres is encountered. This finding

  12. Migration of a surfactant-laden droplet in non-isothermal Poiseuille flow (United States)

    Das, Sayan; Mandal, Shubhadeep; Som, S. K.; Chakraborty, Suman


    The motion of a surfactant-laden viscous droplet in the presence of non-isothermal Poiseuille flow is studied analytically and numerically. Specifically, the focus of the present study is on the role of interfacial Marangoni stress generated due to imposed temperature gradient and non-uniform distribution of bulk-insoluble surfactants towards dictating the velocity and direction of motion of the droplet when the background flow is Poiseuille. Assuming the thermal convection and fluid inertia to be negligible, we obtain the explicit expression for steady velocity of a non-deformable spherical droplet when the droplet is located at the centerline of the imposed unbounded Poiseuille flow and encountering a linearly varying temperature field. Under these assumptions, the interfacial transport of surfactants is governed by the surface Péclet number which represents the relative strength of the advective transport of surfactant molecules over the diffusive transport. We obtain analytical solution for small and large values of the surface Péclet number. Analytical solution is also obtained for the case in which the surface Péclet number is of order unity by considering small surfactant Marangoni number which represents the relative strength of the surfactant-induced Marangoni stress over the viscous stress. For an arbitrary surface Péclet number, a numerical solution of the surfactant transport equation is performed using an iterative method which compares well with the analytical solutions. Depending on the direction of temperature gradient with respect to the imposed Poiseuille flow, the surfactant-induced Marangoni stress affects the droplet velocity significantly. When the imposed temperature increases in the direction of imposed Poiseuille flow, surfactants retard the droplet motion as compared with a surfactant-free droplet. However, when the imposed temperature decreases in the direction of imposed Poiseuille flow, the presence of surfactants may increase or

  13. One-step generation of engineered drug-laden poly(lactic-co-glycolic acid) micropatterned with Teflon chips for potential application in tendon restoration. (United States)

    Shi, Xuetao; Zhao, Yihua; Zhou, Jianhua; Chen, Song; Wu, Hongkai


    Regulating cellular behaviors such as cellular spatial arrangement and cellular phenotype is critical for managing tissue microstructure and biological function for engineered tissue regeneration. We herein pattern drug-laden poly(lactic-co-glycolic acid) (PLGA) into grooves using novel Teflon stamps (that possess excellent properties of resistance to harsh organic solvents and molecular adsorption) for engineered tendon-repair therapeutics. The drug release and biological properties of melatonin-laden PLGA grooved micropatterns are investigated. The results reveal that fibroblasts cultured on the melatonin-laden PLGA groove micropatterns not only display significant cell alignment that mimics the cell behavior in native tendon, but also promote the secretion of a major extracellular matrix in tendon, type I collagen, indicating great potential for the engineering of functional tendon regeneration.

  14. A direct comparison of fully resolved and point-particle models in particle-laden turbulent flow (United States)

    Horwitz, Jeremy; Mehrabadi, Mohammad; Subramaniam, Shankar; Mani, Ali


    Point-particle methods have become a popular methodology to simulate viscous fluids laden with dispersed solid elements. Such methods may be contrasted with particle-resolved methods, whereby the boundary conditions between particles and fluid are treated exactly, while point-particle methods do not capture the boundary conditions exactly and couple the continuous and dispersed phase via point-forces. This allows point-particle methods to simulate particle-turbulence interaction at considerably lower resolution and computational cost than particle-resolved methods. However, lack of validation of point-particle methods begs the question of the predictive power of point-particle methods. In other words, can point-particle methods recover particle and fluid statistics compared with particle-resolved simulation of dynamically equivalent non-dimensional problems? We address this question in this work by examining decaying homogeneous isotropic turbulence laden with particles. For the same nominal conditions, we compare statistics predicted by a particle resolved method to those predicted by a point-particle method. We also examine the effect of the undisturbed velocity in the point-particle drag law by studying the same problem with a correction scheme. Supported by DOE and NSF.

  15. A novel state-space based method for direct numerical simulation of particle-laden turbulent flows (United States)

    Ranjan, Reetesh; Pantano, Carlos


    We present a novel state-space-based numerical method for transport of the particle density function, which can be used to investigate particle-laden turbulent flows. Here, the problem can be stated purely in a deterministic Eulerian framework. The method is coupled to an incompressible three-dimensional flow solver. We consider a dilute suspension where the volume fraction and mass loading of the particles in the flow are low enough so that the approximation of one-way coupling remains valid. The particle transport equation is derived from the governing equation of the particle dynamics described in a Lagrangian frame, by treating position and velocity of the particle as state-space variables. Application and features of this method will be demonstrated by simulating a particle-laden decaying isotropic turbulent flow. It is well known that even in an isotropic turbulent flow, the distribution of particles is not uniform. For example, heavier-than-fluid particles tend to accumulate in regions of low vorticity and high strain rate. This lead to large regions in the flow where particles remain sparsely distributed. The new approach can capture the statistics of the particle in such sparsely distributed regions in an accurate manner compared to other numerical methods.

  16. Large-eddy simulation of particle-laden flow over a backward-facing step using a spectral multidomain method (United States)

    Sengupta, Kaustav; Jacobs, Gustaaf; Mashayek, Farzad


    We present an investigation into the particle-laden flow in a dump-combustor configuration. An accurate prediction of particle dispersion within the combustors is necessary for improved design of spray combustion. The instantaneous local particle concentration and turbulent mixing provide insights into the physio-chemical processes that would be encountered in a reacting scenario. The principal difficulty in prediction of particle transport in the dilute flow regime, lies in the accurate description of the underlying complex, turbulent gas flow field featuring reattaching shear layers. Here, we present large-eddy simulations (LESs) of a particle-laden flow over an unconfined and confined backward-facing step at Reynolds numbers of 5000 and 28,000, respectively, using a spectral multidomain LES methodology. The LES captures the carrier flow accurately, while being computationally affordable. One-way coupled equations are considered and particles with different Stokes numbers are studied. The inlet turbulence is modeled using a novel stochastic model that reproduces the second order moments of the fully developed flow upstream of the step. The effects of the turbulent recirculating flow behind the step on particle dispersion are investigated in detail.

  17. Bioregeneration of perchlorate-laden gel-type anion-exchange resin in a fluidized bed reactor. (United States)

    Venkatesan, Arjun K; Sharbatmaleki, Mohamadali; Batista, Jacimaria R


    Selective ion-exchange resins are very effective to remove perchlorate from contaminated waters. However, these resins are currently incinerated after one time use, making the ion-exchange process incomplete and unsustainable for perchlorate removal. Resin bioregeneration is a new concept that combines ion-exchange with biological reduction by directly contacting perchlorate-laden resins with a perchlorate-reducing bacterial culture. In this research, feasibility of the bioregeneration of perchlorate-laden gel-type anion-exchange resin was investigated. Bench-scale bioregeneration experiments, using a fluidized bed reactor and a bioreactor, were performed to evaluate the feasibility of the process and to gain insight into potential mechanisms that control the process. The results of the bioregeneration tests suggested that the initial phase of the bioregeneration process might be controlled by kinetics, while the later phase seems to be controlled by diffusion. Feasibility study showed that direct bioregeneration of gel-type resin was effective in a fluidized-bed reactor, and that the resin could be defouled, reused, and repeatedly regenerated using the method applied in this research.

  18. Bioregeneration of perchlorate-laden gel-type anion-exchange resin in a fluidized bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Venkatesan, Arjun K.; Sharbatmaleki, Mohamadali [Department of Civil and Environmental Engineering, University of Nevada Las Vegas (UNLV), 4505 Maryland Parkway, Las Vegas, NV 89154-4015 (United States); Batista, Jacimaria R., E-mail: [Department of Civil and Environmental Engineering, University of Nevada Las Vegas (UNLV), 4505 Maryland Parkway, Las Vegas, NV 89154-4015 (United States)


    Selective ion-exchange resins are very effective to remove perchlorate from contaminated waters. However, these resins are currently incinerated after one time use, making the ion-exchange process incomplete and unsustainable for perchlorate removal. Resin bioregeneration is a new concept that combines ion-exchange with biological reduction by directly contacting perchlorate-laden resins with a perchlorate-reducing bacterial culture. In this research, feasibility of the bioregeneration of perchlorate-laden gel-type anion-exchange resin was investigated. Bench-scale bioregeneration experiments, using a fluidized bed reactor and a bioreactor, were performed to evaluate the feasibility of the process and to gain insight into potential mechanisms that control the process. The results of the bioregeneration tests suggested that the initial phase of the bioregeneration process might be controlled by kinetics, while the later phase seems to be controlled by diffusion. Feasibility study showed that direct bioregeneration of gel-type resin was effective in a fluidized-bed reactor, and that the resin could be defouled, reused, and repeatedly regenerated using the method applied in this research.

  19. The 3D printing of gelatin methacrylamide cell-laden tissue-engineered constructs with high cell viability. (United States)

    Billiet, Thomas; Gevaert, Elien; De Schryver, Thomas; Cornelissen, Maria; Dubruel, Peter


    In the present study, we report on the combined efforts of material chemistry, engineering and biology as a systemic approach for the fabrication of high viability 3D printed macroporous gelatin methacrylamide constructs. First, we propose the use and optimization of VA-086 as a photo-initiator with enhanced biocompatibility compared to the conventional Irgacure 2959. Second, a parametric study on the printing of gelatins was performed in order to characterize and compare construct architectures. Hereby, the influence of the hydrogel building block concentration, the printing temperature, the printing pressure, the printing speed, and the cell density were analyzed in depth. As a result, scaffolds could be designed having a 100% interconnected pore network in the gelatin concentration range of 10-20 w/v%. In the last part, the fabrication of cell-laden scaffolds was studied, whereby the application for tissue engineering was tested by encapsulation of the hepatocarcinoma cell line (HepG2). Printing pressure and needle shape was revealed to impact the overall cell viability. Mechanically stable cell-laden gelatin methacrylamide scaffolds with high cell viability (>97%) could be printed.

  20. Airway cellularity, lipid laden macrophages and microbiology of gastric juice and airways in children with reflux oesophagitis

    Directory of Open Access Journals (Sweden)

    Lewindon PJ


    Full Text Available Abstract Background Gastroesophageal reflux disease (GORD can cause respiratory disease in children from recurrent aspiration of gastric contents. GORD can be defined in several ways and one of the most common method is presence of reflux oesophagitis. In children with GORD and respiratory disease, airway neutrophilia has been described. However, there are no prospective studies that have examined airway cellularity in children with GORD but without respiratory disease. The aims of the study were to compare (1 BAL cellularity and lipid laden macrophage index (LLMI and, (2 microbiology of BAL and gastric juices of children with GORD (G+ to those without (G-. Methods In 150 children aged Results BAL neutrophil% in G- group (n = 63 was marginally but significantly higher than that in the G+ group (n = 77, (median of 7.5 and 5 respectively, p = 0.002. Lipid laden macrophage index (LLMI, BAL percentages of lymphocyte, eosinophil and macrophage were similar between groups. Viral studies were negative in all, bacterial cultures positive in 20.7% of BALs and in 5.3% of gastric aspirates. BAL cultures did not reflect gastric aspirate cultures in all but one child. Conclusion In children without respiratory disease, GORD defined by presence of reflux oesophagitis, is not associated with BAL cellular profile or LLMI abnormality. Abnormal microbiology of the airways, when present, is not related to reflux oesophagitis and does not reflect that of gastric juices.

  1. Bioprinting 3D cell-laden hydrogel microarray for screening human periodontal ligament stem cell response to extracellular matrix. (United States)

    Ma, Yufei; Ji, Yuan; Huang, Guoyou; Ling, Kai; Zhang, Xiaohui; Xu, Feng


    Periodontitis is an inflammatory disease negatively affecting up to 15% of adults worldwide. Periodontal ligament stem cells (PDLSCs) hold great promises for periodontal tissue regeneration, where it is necessary to find proper extracellular matrix (ECM) materials (e.g., composition, concentration). In this study, we proposed a bioprinting-based approach to generate nano-liter sized three-dimensional (3D) cell-laden hydrogel array with gradient of ECM components, through controlling the volume ratio of two hydrogels, such as gelatin methacrylate (GelMA) and poly(ethylene glycol) (PEG) dimethacrylate. The resulting cell-laden array with a gradient of GelMA/PEG composition was used to screen human PDLSC response to ECM. The behavior (e.g., cell viability, spreading) of human PDLSCs in GelMA/PEG array were found to be depended on the volume ratios of GelMA/PEG, with cell viability and spreading area decreased along with increasing the ratio of PEG. The developed approach would be useful for screening cell-biomaterial interaction in 3D and promoting regeneration of functional tissue.

  2. 3D bioprinting of BMSC-laden methacrylamide gelatin scaffolds with CBD-BMP2-collagen microfibers. (United States)

    Du, Mingchun; Chen, Bing; Meng, Qingyuan; Liu, Sumei; Zheng, Xiongfei; Zhang, Cheng; Wang, Heran; Li, Hongyi; Wang, Nuo; Dai, Jianwu


    Three-dimensional (3D) bioprinting combines biomaterials, cells and functional components into complex living tissues. Herein, we assembled function-control modules into cell-laden scaffolds using 3D bioprinting. A customized 3D printer was able to tune the microstructure of printed bone mesenchymal stem cell (BMSC)-laden methacrylamide gelatin scaffolds at the micrometer scale. For example, the pore size was adjusted to 282 ± 32 μm and 363 ± 60 μm. To match the requirements of the printing nozzle, collagen microfibers with a length of 22 ± 13 μm were prepared with a high-speed crusher. Collagen microfibers bound bone morphogenetic protein 2 (BMP2) with a collagen binding domain (CBD) as differentiation-control module, from which BMP2 was able to be controllably released. The differentiation behaviors of BMSCs in the printed scaffolds were compared in three microenvironments: samples without CBD-BMP2-collagen microfibers in the growth medium, samples without microfibers in the osteogenic medium and samples with microfibers in the growth medium. The results indicated that BMSCs showed high cell viability (>90%) during printing; CBD-BMP2-collagen microfibers induced BMSC differentiation into osteocytes within 14 days more efficiently than the osteogenic medium. Our studies suggest that these function-control modules are attractive biomaterials and have potential applications in 3D bioprinting.

  3. Thermodynamic and kinetic studies of dioxin formation and emissions from power boilers burning salt-laden wood waste

    Energy Technology Data Exchange (ETDEWEB)

    Duo, W.; Leclerc, D. [Pulp and Paper Research Institute of Canada (Paprican) (Canada)


    Wikstrom et al. investigated PCDD/F formation in the combustion of an artificial fuel with PVC or CaCl{sub 2} added. They found no correlation between the levels of dioxin formation and the fuel chlorine content. However, Yasuhara et al. observed increases in dioxin formation with the NaCl content when impregnated newspapers were incinerated. In power boilers burning salt-laden hog fuel, the chlorine is introduced mainly as NaCl. To our knowledge, high temperature salt chemistry and its influence on dioxin formation in combustion and thermal processes have not been thoroughly studied. A thermodynamic analysis of the salt chemistry will be provided in this paper. Though largely empirical, most of the kinetic models developed to describe PCDD/F formation rates are complicated, containing 8 - 12 parameters that need to be estimated. Everaert and Baeyens reported a very simple correlation between stack PCDD/F emissions and the electrostatic precipitator (ESP) temperature: log(PCDD/F){sub T} = (0.016T - 3.001). Although this correlation cannot quantitatively predict dioxin emissions measured on the Canadian west coastal power boilers burning salt-laden hog fuel, the effect of ESP temperature given in the correlation agrees qualitatively. In this work, we will attempt to develop a semi-empirical model based upon both thermodynamic analysis and kinetic considerations.

  4. On the Influence of Superstructures and Deckhouses upon Longitudinal Strength%上层建筑(甲板室)参与总纵强度程度分析

    Institute of Scientific and Technical Information of China (English)

    郭际; 肖渤舰


    具有发达上层建筑的大型豪华游轮已经成为当前游轮的发展趋势,而关于其上层建筑参与总纵弯曲的程度并未得到系统研究。文中结合有限元方法就这一问题进行探讨,定量分析上层建筑层数、开口尺寸及侧壁距舷侧距离等因素对上层建筑参与总纵弯曲的影响。%Cruise ship with multiple floor superstructures has become more and more popular .However , the longitudinal strength of superstructures has not been well studied .In this paper , the number of superstructures , hole size and the distance be-tween superstructure side and ship side which may have influence on the longitudinal strength of superstructures were studied by finite element method .

  5. A second-order accurate immersed boundary-lattice Boltzmann method for particle-laden flows

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Qiang; Fan, Liang-Shih, E-mail:


    A new immersed boundary-lattice Boltzmann method (IB-LBM) is presented for fully resolved simulations of incompressible viscous flows laden with rigid particles. The immersed boundary method (IBM) recently developed by Breugem (2012) [19] is adopted in the present method, development including the retraction technique, the multi-direct forcing method and the direct account of the inertia of the fluid contained within the particles. The present IB-LBM is, however, formulated with further improvement with the implementation of the high-order Runge–Kutta schemes in the coupled fluid–particle interaction. The major challenge to implement high-order Runge–Kutta schemes in the LBM is that the flow information such as density and velocity cannot be directly obtained at a fractional time step from the LBM since the LBM only provides the flow information at an integer time step. This challenge can be, however, overcome as given in the present IB-LBM by extrapolating the flow field around particles from the known flow field at the previous integer time step. The newly calculated fluid–particle interactions from the previous fractional time steps of the current integer time step are also accounted for in the extrapolation. The IB-LBM with high-order Runge–Kutta schemes developed in this study is validated by several benchmark applications. It is demonstrated, for the first time, that the IB-LBM has the capacity to resolve the translational and rotational motion of particles with the second-order accuracy. The optimal retraction distances for spheres and tubes that help the method achieve the second-order accuracy are found to be around 0.30 and −0.47 times of the lattice spacing, respectively. Simulations of the Stokes flow through a simple cubic lattice of rotational spheres indicate that the lift force produced by the Magnus effect can be very significant in view of the magnitude of the drag force when the practical rotating speed of the spheres is encountered

  6. Yttrium and hydrogen superstructure and correlation of lattice expansion and proton conductivity in the BaZr0.9Y0.1O2.95 proton conductor (United States)

    Braun, A.; Ovalle, A.; Pomjakushin, V.; Cervellino, A.; Erat, S.; Stolte, W. C.; Graule, T.


    Bragg reflections in Y-resonant x-ray diffractograms of BaZr0.9Y0.1O2.95 (BZY10) reveal that Y is organized in a superstructure. Comparison with neutron diffraction superstructure reflections in protonated/deuterated BZY10 suggests that both superstructures are linked, and that protons move in the landscape imposed by the Y. The thermal lattice expansion decreases abruptly for protonated BZY10 at T ≥648±20 K, coinciding with the onset of lateral proton diffusion and suggesting a correlation of structural changes and proton conductivity. The chemical shift in the Y L1-shell x-ray absorption spectra reveals a reduction from Y3+ toward Y2+ upon protonation.

  7. Investigation of the incommensurate and commensurate magnetic superstructures of LiCuVO4 and CuO on the basis of the isotropic spin exchange and classical spin approximations. (United States)

    Dai, D; Koo, H-J; Whangbo, M-H


    The spin lattices of magnetic oxides LiCuVO(4) and CuO are made up of CuO(2) ribbon chains. The incommensurate and commensurate magnetic superstructures of these oxides were examined by calculating the total spin exchange interaction energies of their long-range order spin arrangements on the basis of the isotropic spin exchange and classical spin approximations. The incommensurate superstructure (0, 0.532, 0) of LiCuVO(4) was analyzed to find that the next-nearest-neighbor spin exchange interaction J(nnn) is more strongly antiferromagnetic than the nearest-neighbor spin exchange interaction J(nn) in the CuO(2) chains. With this finding, we reassessed the relative strengths of the spin exchange interactions of LiCuVO(4) and CuO and then analyzed the relative energies of their long-range order spin arrangements. The incommensurate superstructure (0, 0.532, 0) of LiCuVO(4) is explained when the J(nn)/J(nnn) ratio is -0.40. Both the incommensurate superstructure (0.506, 0, -0.483) and the commensurate superstructure (0.5, 0, -0.5) of CuO, which occur at 231 and 212.5 K, respectively, are well explained in terms of the calculated total spin exchange interaction energies. The incommensurate superstructure of CuO becomes commensurate by a slight change in one interchain spin exchange interaction, which is due probably to a slight structure change brought about by the temperature lowering.

  8. Ultra-high-speed digital in-line holography system applied to particle-laden supersonic underexpanded jet flows

    DEFF Research Database (Denmark)

    Ingvorsen, Kristian Mark; Buchmann, Nicolas A.; Soria, Julio


    for magnified digital in-line holography is created, using an ultra-high-speed camera capable of frame rates of up to 1.0MHz. To test the new technique an axisymmetric supersonic underexpanded particle-laden jet is investigated. The results show that the new technique allows for the acquisition of time resolved...

  9. Enzymatic Crosslinking of Polymer Conjugates is Superior over Ionic or UV Crosslinking for the On-Chip Production of Cell-Laden Microgels

    NARCIS (Netherlands)

    Henke, S.J.; Leijten, J.C.H.; Kemna, E.W.M.; Neubauer, M.; Fery, A.; Berg, van den A.; Apeldoorn, van A.A.; Karperien, H.B.J.


    Cell-laden micrometer-sized hydrogels (microgels) hold great promise for improving high throughput ex-vivo drug screening and engineering biomimetic tissues. Microfluidics is a powerful tool to produce microgels. However, only a limited amount of biomaterials have been reported to be compatible with

  10. Controllable synthesis of 3D BiVO₄ superstructures with visible-light-induced photocatalytic oxidation of NO in the gas phase and mechanistic analysis. (United States)

    Ou, Man; Nie, Haoyu; Zhong, Qin; Zhang, Shule; Zhong, Lei


    A surfactant-free solvothermal method was developed for the controlled synthesis of diverse 3D ms-BiVO4 superstructures, including a flower, a double-layer half-open flower and a hollow tube with square cross-sections, via facilely adjusting the pH values with the aid of NH3·H2O. The effects of the morphologies of the prepared 3D ms-BiVO4 superstructure on the photocatalytic oxidation of NO were investigated, indicating that the enhanced photoactivity was not related to the surface area, but associated with the unique morphology, surface structure and good crystallinity. Moreover, the flower-like ms-BiVO4 photocatalyst with a more (040) reactive crystal plane exhibited higher photoactivity than those of other samples. The unique morphology helped with flushing the oxidation products accumulated on the surface of photocatalysts in the H2O2 system, and further improved the photoactivity. A trapping experiment was also conducted to examine the effects of the active species involved in the PCO of NO intuitively.

  11. Spiral Patterning of Au Nanoparticles on Au Nanorod Surface to Form Chiral AuNR@AuNP Helical Superstructures Templated by DNA Origami. (United States)

    Shen, Chenqi; Lan, Xiang; Zhu, Chenggan; Zhang, Wei; Wang, Leyu; Wang, Qiangbin


    Plasmonic motifs with precise surface recognition sites are crucial for assembling defined nanostructures with novel functionalities and properties. In this work, a unique and effective strategy is successfully developed to pattern DNA recognition sites in a helical arrangement around a gold nanorod (AuNR), and a new set of heterogeneous AuNR@AuNP plasmonic helices is fabricated by attaching complementary-DNA-modified gold nanoparticles (AuNPs) to the predesigned sites on the AuNR surface. AuNR is first assembled to one side of a bifacial rectangular DNA origami, where eight groups of capture strands are selectively patterned on the other side. The subsequently added link strands make the rectangular DNA origami roll up around the AuNR into a tubular shape, therefore giving birth to a chiral patterning of DNA recognition sites on the surface of AuNR. Following the hybridization with the AuNPs capped with the complementary strands to the capture strands on the DNA origami, left-handed and right-handed AuNR@AuNP helical superstructures are precisely formed by tuning the pattern of the recognition sites on the AuNR surface. Our strategy of nanoparticle surface patterning innovatively realizes hierarchical self-assembly of plasmonic superstructures with tunable chiroptical responses, and will certainly broaden the horizon of bottom-up construction of other functional nanoarchitectures with growing complexity.

  12. Contribution of TEMPO-Oxidized Cellulose Gel in the Formation of Flower-Like Zinc Oxide Superstructures: Characterization of the TOCgel/ZnO Composite Films

    Directory of Open Access Journals (Sweden)

    Khalil Jradi


    Full Text Available In the present paper, we report on a simple and new approach for the synthesis of hierarchical flower-like zinc oxide superstructures ZnO (FL in the presence of the TEMPO-oxidized cellulose gel (TOCgel through a room temperature sol-gel process in aqueous medium. Resulting composite films based on TOCgel and ZnO were investigated by several techniques including scanning electron microscopy (SEM, Fourier transform infrared spectroscopy (FTIR, X-ray photoelectron spectroscopy (XPS, thermogravimetric analysis (TGA and mechanical tests. SEM images demonstrated the formation of well-shaped flower-like ZnO superstructures within the fibrous structure of the TOCgel with a uniform diameter (~5 μm. FTIR and XPS results clearly confirmed the formation of such ZnO structures. We suggested that the carboxylate groups of TOCgel fibers act as capping agents and promote the construction of such flower-like ZnO via a nucleation-growth process. A proposed mechanism based on the oriented attachment-driven growth was discussed in order to explain the formation of ZnO (FL. The photocatalytic activity of the TOCgel/ZnO composite in the degradation of methylene blue (MB under UV irradiation was clearly confirmed. Finally, mechanical tests demonstrated that the former TOCgel/ZnO film maintained a good flexibility (bent up to ~120° without losing its photocatalytic activity.

  13. A κ—ε—PDF Two—Phase Turbulence Model for Simulating Sudden—Expansion Particle—Laden FLows

    Institute of Scientific and Technical Information of China (English)

    Y.Li; L.X.Zhou


    A κ-ε-PDF model based on statistical theory for turbulent gas-particle flows is proposed.and a numerical procedure combining the finite difference and finite fluctuaing-velocity-group methods is used.The obtained statistically averaged equations have the same form as those obtained by using the Reynolds averaging.Using the κ-ε-PDF model(PDF particle turbulence model combined with the κ-ε- gas turbulence model),amny terms,such as the diffusion term in particle Reynolds Stress equations,can be accurately calcuated for verifying the second-moment-closure model,the κ-ε-PDF model is used to simulate sudden-expansion particle-laden flow.comparison of the predictions using both κ-ε-PDF and the κ-ε- models with experimental results shows that the κ-ε-PDF model give more reasonable non-siotropic features of particle turbulence.

  14. The study of droplet-laden turbulent air-flow over waved water surface by direct numerical simulation (United States)

    Druzhinin, Oleg A.; Troitskaya, Yuliya I.; Zilitinkevich, Sergej S.


    The detailed knowledge of the interaction of wind with surface water waves is necessary for correct parameterization of turbulent exchange at the air-sea interface in prognostic models. At sufficiently strong winds, sea-spray-generated droplets interfere with the wind-waves interaction. The results of field experiments and laboratory measurements (Andreas et al., JGR 2010) show that mass fraction of air-borne spume water droplets increases with the wind speed and their impact on the carrier air-flow may become significant. Phenomenological models of droplet-laden marine atmospheric boundary layer (Kudryavtsev & Makin, Bound.-Layer Met. 2011) predict that droplets significantly increase the wind velocity and suppress the turbulent air stress. The results of direct numerical simulation (DNS) of a turbulent particle-laden Couette flow over a flat surface show that inertial particles may significantly reduce the carrier flow vertical momentum flux (Richter & Sullivan, GRL 2013). The results also show that in the range of droplet sizes typically found near the air-sea interface, particle inertial effects are significant and dominate any particle-induced stratification effects. However, so far there has been no attempt to perform DNS of a droplet-laden air-flow over waved water surface. In this report, we present results of DNS of droplet-laden, turbulent Couette air-flow over waved water surface. The carrier, turbulent Couette-flow configuration in DNS is similar to that used in previous numerical studies (Sullivan et al., JFM 2000, Shen et al., JFM 2010, Druzhinin et al., JGR 2012). Discrete droplets are considered as non-deformable solid spheres and tracked in a Lagrangian framework, and their impact on the carrier flow is modeled with the use of a point-force approximation. The droplets parameters in DNS are matched to the typical known spume-droplets parameters in laboratory and field experiments. The DNS results show that both gravitational settling of droplets and

  15. 21st Century-based Soft Skills: Spotlight on Non-cognitive Skills in a Cognitive-laden Dentistry Program

    Directory of Open Access Journals (Sweden)

    Marjorie C. Quieng


    Full Text Available Teaching and learning in the 21st century aim to produce students proficient in content knowledge, specific abilities, literacy, numeracy, and technology uses. From these 21st century skills, soft skills were delineated from these learning outcomes; and defined as intra- and interpersonal skills vital for personal development, social participation, and workplace success. This study has two goals: to determine the perceived extent of integration of 21st century-based soft skills in the cognitive-laden dentistry curriculum, and to examine the perceived 21st century-based soft skills of the student participants to serve as baseline data for future research. Communication, and relationship and collaboration skills will be critical components to motivate students; in turn, when students are motivated, it will encourage them to think critically and initiate actions toward the achievement of their goals.

  16. Assessment of particle-tracking models for dispersed particle-laden flows implemented in OpenFOAM and ANSYS FLUENT

    Directory of Open Access Journals (Sweden)

    Franziska Greifzu


    Full Text Available In the present study two benchmark problems for turbulent dispersed particle-laden flow are investigated with computational fluid dynamics (CFD. How the CFD programs OpenFOAM and ANSYS FLUENT model these flows is tested and compared. The numerical results obtained with Lagrangian–Eulerian (LE point-particle (PP models for Reynolds-averaged Navier–Stokes (RANS simulations of the fluid flow in steady state and transient modes are compared with the experimental data available in the literature. The effect of the dispersion model on the particle motion is investigated in particular, as well as the order of coupling between the continuous carrier phase and the dispersed phase. First, a backward-facing step (BFS case is validated. As a second case, the confined bluff body (CBB is used. The simulated fluid flows correspond well with the experimental data for both test cases. The results for the dispersed solid phase reveal a good accordance between the simulation results and the experiments. It seems that particle dispersion is slightly under-predicted when ANSYS FLUENT is used, whereas the applied solver in OpenFOAM overestimates the dispersion somewhat. Only minor differences between the coupling schemes are detected due to the low volume fractions and mass loadings that are investigated. In the BFS test case the importance of the spatial dimension of the numerical model is demonstrated. Even if it is reasonable to assume a two-dimensional fluid flow structure, it is crucial to simulate the turbulent particle-laden flow with a three-dimensional model since the turbulent dispersion of the particles is three-dimensional.

  17. Medical training as adventure-wonder and adventure-ordeal: a dialogical analysis of affect-laden pedagogy. (United States)

    Madill, Anne; Sullivan, Paul


    Our purpose is to examine the possibilities of Bakhtinian dialogical analysis for understanding students' experiences of medical training. Twenty-three interviews were conducted with eleven British medical students intercalating in psychology. Forty emotionally resonant key moments were identified for analysis. Our analysis illustrates students' use of the professional genre to present their training as emotionally neutral. However, we show how medical training can be framed in more unofficial and affective-laden ways in which threshold moments of crisis are presented as space-time breaches characteristic of the genres of adventure-wonder and adventure-ordeal. This affect was often depotentiated in the narratives through brief allusion to the professional genre. This cycling between genres suggests that the students were searching for an appropriate way in which to frame their experiences, a central dilemma being the extent to which medical training makes sense within an immediate and affect-laden, or future-orientated and affect-neutral, pedagogy. Finally, we identify how consultants are an important aspect of the affective experience of medical training who, at their best, offer inspiring exemplars of flexible movement between official and unofficial ways of being a doctor. In conclusion, we demonstrate the potential of genres to make sense, and to organize the experience, of medical training spatially in terms of moving between personal and impersonal contact, temporally in terms of moving between the extraordinary and routine, and affectively in terms of moving between potent and neutral affect. Learning to use the professional genre is part of enculturation as a doctor and can be helpful in providing a framework restoring coherence and composure through engaging with, and reformulating, difficult experiences. However, it is important to take seriously the resistance many of the students demonstrated to the professional genre as a possible barometer of its

  18. Synthesis and Characterization of Featherlike Hierarchical Fe-Co Alloy Superstructures%羽状Fe-Co合金分级结构粒子的合成与表征

    Institute of Scientific and Technical Information of China (English)

    王维; 阳振军


    Featherlike hierarchical Fe-Co alloy superstructures are synthesized by using FeCl3 ·6H2 O as the source of iron and sodium citrate as shape-controlling agent. The morphology and composition of the samples are characterized by SEM, EDX and XRD etc. It is have been found that sodium citrate play a key role in forming hierarchical superstructures,the formation mechanism of featherlike superstructures could be ascribed to Diffusion-Limited Aggregation ( DLA) theory: The previous nanocrystals tend to join each other along with direction of the crystal plane without adsorbed sodium citrate and then to form intermediate superstruc-tures, and well-development featherlike superstructures are generated after further growth under the action of Ostwald ripening.%分别以柠檬酸钠和FeCl3·6H2 O为形状控制剂和铁源制备了羽状Fe-Co合金分级结构粒子。用扫描电镜、能谱和X射线衍射对样品的形貌、成分进行了表征分析,并研究了柠檬酸钠用量对产物的影响。结果表明羽状分级结构形成机理可以用扩散限制聚集理论解释,即前期纳米晶核在没有柠檬酸根吸附的晶面上定向聚集形成松散的枝状结构,最后经过奥斯特瓦尔德熟化成羽叶状分级结构。

  19. Role of Ordering Energy in Formation of Grain Structure and Special Boundaries Spectrum in OrderedAlloys with L12 Superstructure

    Institute of Scientific and Technical Information of China (English)


    It was revealed that an average energy of special boundaries is proportional to APB energy in the alloys with the L12 superstructure. This fact proves the appearance of the GAPBs in the planes of location of special boundaries in coincidence sites of ordered alloys. It was determined that the more energy of special boundaries in ordered alloys, the more energy of complex stacking fault. There is a correlation between the distribution of special boundaries as a function its relative energy and ordering energy: the more ordering energy, the more degree of washed away of distribution. The correlation between average relative energy of special boundaries and ordering energy was detected: the more ordering energy, the more average energy of special boundaries. The reverse dependence between ordering energy and average number of special boundaries in grains limited by boundaries of general type was discovered.

  20. Influence of temperature on the controlled growth kinetics and superstructural phase formation of indium on a reconstructed Si (113) 3 × 2 surface (United States)

    Krishna TC, Shibin; Deshmukh, Rahul; Singh Chauhan, Amit Kumar; Goswami, Lalit; Govind


    The kinetics of growth, thermal stability and superstructural phase formation of the indium atom on a reconstructed Si (113) 3 × 2 surface at room temperature (RT), as well as at high substrate temperature (HT), is discussed. It was observed that at a very low flux rate of 0.08 ML min-1, In-adsorption at RT follows the Frank-van der Merwe (FM) growth mode, while for HT (>200 °C), In-islands (the Volmer-Weber-growth mode) were formed. The residual thermal desorption (RTD) analysis revealed the anomalous behaviour of temperature-driven layering to the clustering rearrangement of In atoms on the Si (113) surface for RT- and 200 °C-grown systems. The RTD study also demonstrates the effect of temperature on growth kinetics as well as on the multilayer/monolayer desorption pathway. The calculated bilayer desorption energy was found to be different for RT- (T B, 0.48 eV) and HT- (T B, 1.57 eV) grown In/Si(113) systems, while the monolayer desorption energy (T M, 2.56 eV) was the same in both the cases. Various coverage-dependent superstructural phases, such as Si(113) 3 × 2 + 3 × 1, 3 × 1, 3 × 2 + 1 × 3 and 1 × 1, have been observed during the RT- and HT-growth of In on the Si (113) surface. A complete phase diagram of In/Si(113) is deduced which depicts the evolution of novel phases as a function of substrate temperature and coverage.

  1. Three-dimensional surface-enhanced Raman scattering hotspots in spherical colloidal superstructure for identification and detection of drugs in human urine. (United States)

    Han, Zhenzhen; Liu, Honglin; Wang, Bin; Weng, Shizhuang; Yang, Liangbao; Liu, Jinhuai


    Rapid component separation and robust surface-enhanced Raman scattering (SERS) identification of drugs in real human urine remain an attractive challenge because of the sample complexity, low molecular affinity for metal surface, and inefficient use of hotspots in one- or two-dimensional (2D) geometries. Here, we developed a 5 min strategy of cyclohexane (CYH) extraction for separating amphetamines from human urine. Simultaneously, an oil-in-water emulsion method is used to assemble monodisperse Ag nanoparticles in the CYH phase into spherical colloidal superstructures in the aqueous phase. These superstructures create three-dimensional (3D) SERS hotspots which exist between every two adjacent particles in 3D space, break the traditional 2D limitation, and extend the hotspots into the third dimension along the z-axis. In this platform, a conservative estimate of Raman enhancement factor is larger than 10(7), and the same CYH extraction processing results in a high acceptability and enrichment of drug molecules in 3D hotspots which demonstrates excellent stability and reproducibility and is suitable for the quantitative examination of amphetamines in both aqueous and organic phases. Parallel ultraperformance liquid chromatography (UPLC) examinations corroborate an excellent performance of our SERS platform for the quantitative analysis of methamphetamine (MA) in both aqueous solution and real human urine, of which the detection limits reach 1 and 10 ppb, respectively, with tolerable signal-to-noise ratios. Moreover, SERS examinations on different proportions of MA and 3,4-methylenedioxymethamphetamine (MDMA) in human urine demonstrate an excellent capability of multiplex quantification of ultratrace analytes. By virtue of a spectral classification algorithm, we realize the rapid and accurate recognition of weak Raman signals of amphetamines at trace levels and also clearly distinguish various proportions of multiplex components. Our platform for detecting drugs

  2. 抗氧化剂BHT微胶囊化产品超微结构的测定%Study on Superstructure of Microencapsulated Antioxidant BHT

    Institute of Scientific and Technical Information of China (English)



    Scanning electron microscopy (SEM) was applied to study the superstructure of microencapsulated star butylated hydroxytoluene (BHT) manufactured by various preparation techniques. The results showed that preparation techniques had significant effects on the structure of microencapsulated products, and thus affected the qualities of products. The research about superstructure of BHT could provide information for analyses on the quality of microencapsulate products.%用扫描电子显微镜(SEM)研究抗氧化剂二丁基羟基甲苯(BHT)微胶囊化产品的超微结构.观察了喷雾干燥法不同壁材组成和工艺条件下制作的微胶囊化产品的表面结构和内部结构,同时考察了喷雾干燥进风温度对微胶囊化产品膜结构的影响.结果表明,不同壁材组成和工艺条件下制作的微胶囊化产品的超微结构有较大差异,合适的壁材组成和工艺条件有利于提高产品质量,同时喷雾干燥进风温度对微胶囊化产品的结构有很大影响,从而也影响到产品的质量.微胶囊化产品超微结构的研究为分析影响产品质量的因素提供了重要依据.

  3. A life stage of particle-laden rat dendritic cells in vivo: their terminal division, active phagocytosis, and translocation from the liver to the draining lymph



    Initiation of an adoptive immune response against pathogenic organisms, such as bacteria and fungi, may involve phagocytic activity of dendritic cells (DC) or their immature precursors as a prelude to antigen processing and presentation. After intravenous injection of rats with particulate matter, particle-laden cells were detected in the peripheral hepatic lymph. Since it has been known there is a constant efflux of DC from nonlymphoid organs into the draining peripheral lymph, we examined w...

  4. Performance of an Anaerobic Baffled Filter Reactor in the Treatment of Algae-Laden Water and the Contribution of Granular Sludge


    Yaqin Yu; Xiwu Lu; Yifeng Wu


    This study investigated the performance and stability of an anaerobic baffled filter reactor in the treatment of algae-laden water from Taihu Lake at several organic loading rates. The study also evaluated the capability of soft filler to train granule sludge and improve the anaerobic environment and sludge activity in the anaerobic baffled reactor (ABR), thereby enhancing the treatment efficiency. The ABR consisted of five rectangular compartments, each of which was 120 cm long, 80 cm wide, ...

  5. Mechanically reinforced cell-laden scaffolds formed using alginate-based bioink printed onto the surface of a PCL/alginate mesh structure for regeneration of hard tissue. (United States)

    Kim, Yong Bok; Lee, Hyeongjin; Yang, Gi-Hoon; Choi, Chang Hyun; Lee, DaeWeon; Hwang, Heon; Jung, Won-Kyo; Yoon, Hyeon; Kim, Geun Hyung


    Cell-printing technology has provided a new paradigm for biofabrication, with potential to overcome several shortcomings of conventional scaffold-based tissue regeneration strategies via controlled delivery of various cell types in well-defined target regions. Here we describe a cell-printing method to obtain mechanically reinforced multi-layered cell-embedded scaffolds, formed of micron-scale poly(ε-caprolactone) (PCL)/alginate struts coated with alginate-based bioink. To compare the physical and cellular activities, we used a scaffold composed of pure alginate (without cells) coated PCL/alginate struts as a control. We systematically varied the ratio of alginate cross-linking agent, and determined the optimal cell-coating conditions to form the PCL/alginate struts. Following fabrication of the cell (MG63)-laden PCL/alginate scaffold, the bioactivity was evaluated in vitro. The laden cells exhibited a substantially more developed cytoskeleton compared with those on a control scaffold consisting of the same material composition. Based on these results, the printed cells exhibited a significantly more homogenous distribution within the scaffold compared with the control. Cell proliferation was determined via MTT assays at 1, 3, 7, and 14 days of culture, and the proliferation of the cell-printed scaffold was substantially in excess (∼2.4-fold) of that on the control. Furthermore, the osteogenic activity such as ALP was measured, and the cell-laden scaffold exhibited significantly greater activity (∼3.2-fold) compared with the control scaffold.

  6. Modeling of experimental treatment of acetaldehyde-laden air and phenol-containing water using corona discharge technique. (United States)

    Faungnawakij, Kajornsak; Sano, Noriaki; Charinpanitkul, Tawatchai; Tanthapanichakoon, Wiwut


    Acetaldehyde-laden air and phenol-contaminated water were experimentally treated using corona discharge reactions and gas absorption in a single water-film column. Mathematical modeling of the combined treatment was developed in this work. Efficient removal of the gaseous acetaldehyde was achieved while the corona discharge reactions produced short-lived species such as O and O- as well as ozone. Direct contact of the radicals and ions with water was known to produce aqueous OH radical, which contributes to the decomposition of organic contaminants: phenol, absorbed acetaldehyde, and intermediate byproducts in the water. The influence of initial phenol concentration ranging from 15 to 50 mg L(-1) and that of influent acetaldehyde ranging from 0 to 200 ppm were experimentally investigated and used to build the math model. The maximum energetic efficiency of TOC, phenol, and acetaldehyde were obtained at 25.6 x 10(-9) mol carbon J(-1), 25.0 x 10(-9) mol phenol J(-1), and 2.0 x 10(-9) mol acetaldehyde J(-1), respectively. The predictions for the decomposition of acetaldehyde, phenol, and their intermediates were found to be in good agreement with the experimental results.

  7. Pneumatic-aided micro-molding for flexible fabrication of homogeneous and heterogeneous cell-laden microgels. (United States)

    Ma, Chao; Tian, Chang; Zhao, Lei; Wang, Jinyi


    Microgels are favorable for numerous applications such as drug delivery, biomaterials science and tissue engineering. Conventionally, photolithographic methods and micro-molding techniques are extensively exploited to prepare microgels; however, they are, respectively, limited to photocrosslinkable polymers and inadequate to generate serially patterned hydrogels due to the static nature of utilized molds. Herein, we proposed a simple and versatile approach, termed pneumatic-aided micro-molding (PAM), to flexibly fabricate microgels with precise control over multiple cell types and microarchitectures of hydrogels through strategically designed pneumatic microvalves. Using the PAM approach, different cells were encapsulated in various hydrogels that had well-defined geometries. Additionally, single/multiple micro-channeled cell-laden microgels were fabricated, of which the shape, number and arrangement could be finely tuned by varying microvalve configurations. Moreover, multi-compartmental microgels comprising composite hydrogel structures were engineered following a two-step PAM, which demonstrated the utility for biomimetically constructing a three-dimensional (3D) liver microtissue composed of a radially orchestrated network of hepatic cords and sinusoids. The resulting microtissue resembled the organizational complexity of the liver lobule and was applied for the evaluation of acetaminophen-induced hepatotoxicity. Collectively, the PAM strategy could be a useful and powerful tool in biomedical engineering, in vitro 3D cell culture, and fundamental biological studies.

  8. Routine use of antibiotic laden bone cement for primary total knee arthroplasty: impact on infecting microbial patterns and resistance profiles. (United States)

    Hansen, Erik N; Adeli, Bahar; Kenyon, Robert; Parvizi, Javad


    Antibiotic-laden bone cement (ALBC) is used in primary arthroplasties throughout Europe. In North America, ALBC is only FDA approved for revision arthroplasty after periprosthetic joint infection (PJI). No article has evaluated whether infecting microbial profile and resistance has changed with the introduction of ALBC. We hypothesized that prophylactic use of ALBC in primary total knee arthroplasty (TKA) has not had a significant impact on infecting pathogens, and antibiotic resistance profiles. A retrospective cohort analysis was conducted of all PJI patients undergoing primary TKA and total hip arthroplasty (THA) between January 2000 and January 2009. No significant change in the patterns of infecting PJI pathogens, and no notable increase in percentage resistance was found among organisms grown from patients with PJI that had received prophylactic antibiotic-loaded cement in their primary joint arthroplasty. Early findings suggest that routine prophylactic use of ALBC has not led to changes in infecting pathogen profile, nor has led to the emergence of antimicrobial resistance at our institution.

  9. Metabolism of 25-hydroxyvitamin D in copper-laden rat: A model of Wilson's disease

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, T.O.; Pendrak, M.L.; Anast, C.S. (Harvard Medical School, Boston (USA) Yale Univ. School of Medicine, New Haven, CT (USA))


    Wilson's disease results in excess tissue accumulation of copper and is often complicated by skeletal and mineral abnormalities. The authors investigated vitamin D metabolism in rats fed a copper-laden diet rendering hepatic copper content comparable with that found in Wilson's disease. Injection of 25-hydroxyvitamin D{sub 3} (25(OH)D{sub 3}) resulted in reduced 1,25--dihydroxyvitamin D (1,25(OH){sub 2}D) levels in copper-intoxicated rats. In vitro 25(OH)D-1{alpha}-hydroxylase activity was impaired in renal mitochondria from copper-intoxicated animals. Activity was also inhibited in mitochondrial from controls when copper was added to incubation media. Impaired conversion of 25(OH)D to 1,25(OH){sub 2}D occurs in copper intoxication and suggests that altered vitamin D metabolism is a potential factor in the development of bone and mineral abnormalities in Wilson's disease.

  10. Analytical and numerical simulations of the flow performance of a ferrofluidic magnetic micropump for particle-laden applications

    Energy Technology Data Exchange (ETDEWEB)

    Kilani, M.I. [King Faisal Univ., Al-Ahsa (Saudi Arabia); Jordan Univ., Amman (Jordan). Dept. of Mechatronics Engineering; Al Halhouli, A.T.; Buttgenbach, S. [Inst. for Microtechnology, Braunschweig (Germany)


    New developments in micro-electro-mechanical systems (MEMS) are generating interest in micropump designs for the transport of small quantities of fluid samples. In this study, flow performance in a ferrofluidic magnetic micropump was investigated using analytical and numerical computational fluid dynamics (CFD) simulations. The aim of the study was to provide a method of estimating the stress distribution in the flow field in relation to pump speed and geometry in terms of dimensionless parameters. The pump was valveless, self-priming, bubble-tolerant, and capable of handling particle-laden fluids. Solutions were derived for the shear stress generated at the upper and lower boundaries of the pump's channel by solving the Navier-Stokes equation in cylindrical coordinates. A 3-D computational model of the pump's channel was constructed with different channel heights. The study demonstrated that shear stress is small in the majority of the pump's channel, and develops significant values only in narrow strips near the pump walls. Predictions obtained in the study showed good agreement with results obtained during the CFD simulations. However, CFD predictions were lower than analytical predictions for larger aspect ratios. It was concluded that the estimates provide an upper limit on shear stresses, and can be used to provide conservative estimates of shear stress. 10 refs., 7 figs.

  11. Ab-initio study of gold nanoparticles supported on defect-laden single-layer MoS2 (United States)

    Rawal, Takat B.; Le, Duy; Rahman, Talat S.

    We have investigated the geometry, electronic structure, and catalytic properties of gold nanoparticles on defect-laden single-layer MoS2 using density functional theory (DFT) based calculations with semi-empirical van der Waals interaction (DFT-D3). Our results show that the two-dimensional planar structure, the most favorable one for unsupported Au13 nanoparticle, transforms into a distorted three-dimensional (3D) structure when supported on single-layer MoS2 with single S-vacancy which is more favorable than the icosahedral, decahedron and cuboctahedron forms. The MoS2 support substantially alters the electronic structure of Au13 nanoparticle near the Fermi level, owing to the strong interaction of MoS2 support with Au13 in the presence of an S-vacancy. The modified electronic structure remarkably affects the catalytic activity of the MoS2-supported Au13, offering enhanced activity towards methanol synthesis reaction via CO hydrogenation reaction - a contrast from that of titania-supported Au13 nanoparticlewhich promotes methanol decomposition. This work is supported in part by U.S. Department of Energy (DOE DE-FG02-07ER15842).

  12. Reserves in western basins

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, R.H.; Cotton, B.W. [Scotia Group, Dallas, TX (United States)


    The objective of this project is to investigate the reserves potential of tight gas reservoirs in three Rocky Mountain basins: the Greater Green River (GGRB), Uinta and Piceance basins. The basins contain vast gas resources that have been estimated in the thousands of Tcf hosted in low permeability clastic reservoirs. This study documents the productive characteristics of these tight reservoirs, requantifies gas in place resources, and characterizes the reserves potential of each basin. The purpose of this work is to promote understanding of the resource and to encourage its exploitation by private industry. At this point in time, the GGRB work has been completed and a final report published. Work is well underway in the Uinta and Piceance basins which are being handled concurrently, with reports on these basins being scheduled for the middle of this year. Since the GGRB portion of the project has been completed, this presentation win focus upon that basin. A key conclusion of this study was the subdivision of the resource, based upon economic and technological considerations, into groupings that have distinct properties with regard to potential for future producibility, economics and risk profile.

  13. Record of Decision Remedial Alternative Selection for the C, F, K, and P-Area Coal Pile Runoff Basins (189-C, 289-F, 189-K, and 189-P)

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Randall


    The C-, F-, K-, and P-Area Coal Pile Runoff Basins (189-C, 289-F, 189-K, and 189-P) (C-, F-, K-, and P-CPRBs) waste units are listed as Resource Conservation and Recovery Act (RCRA) 3004(u) Solid Waste Management Units/Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) units in Appendix C of the Federal Facility Agreement (FFA) for the Savannah River Site (SRS). The C-, F-, K-, and P-CPRBS comprise a single operable unit which was remediated under an early removal action during the summer of 1997. Slightly elevated levels of naturally occurring metals and radionuclides in the coal-laden sediments and shallow soils were confined to the 0-1 foot interval below the basin floor. These source materials were identified as low level threat wastes. Under the Removal Site Evaluation Report/Wastewater Closure Plan for the C-, F-, K-, and P-Area Coal Pile Runoff Basins (189-C, 289-F, 189-K, and 189-P) (U) (WSRC 1997b), the coal-laden sediments and shallow soils were removed from each of the four basins during the summer of 1997. At least four feet of clean backfill was placed in each basin to restore the area to the surrounding grade. This removal action completely freed the four CPRBS of the source material for the constituents of concern and the sulfide minerals, which were reducing the pH of the infiltrate. Because the source material has been removed from the CPRBs, releases of hazardous substances will not occur from this operable unit and there is no imminent or substantial endangerment to public health, welfare, or the environment.

  14. Tulare Basin protection plan (United States)

    US Fish and Wildlife Service, Department of the Interior — The Tulare Basin Protection Plan has been initiated by The Nature Conservancy to elucidate the problems and opportunities of natural diversity protection....

  15. Mitigation : Closed Basin Project (United States)

    US Fish and Wildlife Service, Department of the Interior — The upcoming meeting on waterfowl mitigation for the Closed Basin Project will have several people talk about possible changes to the waterfowl mitigation program. A...

  16. California Air Basins (United States)

    California Department of Resources — Air ResourcesCalifornia Air Resources BoardThe following datasets are from the California Air Resources Board: * arb_california_airbasins - California Air BasinsThe...

  17. Watershed Planning Basins (United States)

    Vermont Center for Geographic Information — The Watershed Planning Basin layer is part of a larger dataset contains administrative boundaries for Vermont's Agency of Natural Resources. The dataset includes...

  18. Detailed characteristics of drop-laden mixing layers: Large eddy simulation predictions compared to direct numerical simulation (United States)

    Okong'o, Nora; Leboissetier, Anthony; Bellan, Josette


    Results are compared from direct numerical simulation (DNS) and large eddy simulation (LES) of a temporal mixing layer laden with evaporating drops to assess the ability of LES to reproduce detailed characteristics of DNS. The LES used computational drops, each of which represented eight physical drops, and a reduced flow field resolution using a grid spacing four times larger than that of the DNS. The LES also used models for the filtered source terms, which express the coupling of the drops with the flow, and for the unresolved subgrid-scale (SGS) fluxes of species mass, momentum, and enthalpy. The LESs were conducted using one of three different SGS-flux models: dynamic-coefficient gradient (GRD), dynamic-coefficient Smagorinsky (SMD), and constant-coefficient scale similarity (SSC). The comparison of the LES with the filtered-and-coarsened (FC) DNS considered detailed aspects of the flow that are of interest in ignition or full combustion. All LESs captured the largest-scale vortex, the global amount of vapor emanating from the drops, and the overall size distribution of the drops. All LESs tended to underpredict the global amount of irreversible entropy production (dissipation). The SMD model was found unable to capture either the global or local vorticity variation and had minimal small-scale activity in dynamic and thermodynamic variables compared to the FC-DNS. The SMD model was also deficient in predicting the spatial distribution of drops and of the dissipation. In contrast, the GRD and SSC models did mimic the small-scale activity of the FC-DNS and the spatial distribution of drops and of the dissipation. Therefore, the GRD and SSC models are recommended, while the SMD model seems inappropriate for combustion or other problems where the local activity must be predicted.

  19. Efficient coordination of swarms of sensor-laden balloons for persistent, in situ, real-time measurement of hurricane development* (United States)

    Bewley, Thomas; Meneghello, Gianluca


    Accurate long-term forecasts of the path and intensity of severe hurricanes are imperative to protect property and save lives. Extensive real-time measurements within hurricanes, especially near their core, are essential for supplementing the limited relevant information accessible by satellites in order to improve such forecasts. Current operational methods for obtaining in situ information, such as dropsondes and repeated manned and unmanned aircraft flights over and within hurricanes, are both expensive and limited in duration. In the present work it is demonstrated by numerical experiments how a swarm of robust, inexpensive, buoyancy-controlled, sensor-laden balloons might be deployed and controlled in an energetically efficient, coordinated fashion, for days at a time, to continuously monitor relevant properties (pressure, humidity, temperature, and wind speed) of a hurricane as it develops. Rather than fighting its gale-force winds, the strong and predictable stratification of these winds is leveraged to efficiently disperse the balloons into a favorable time-evolving distribution. An iterative bootstrap approach is envisioned in which (a) sensor balloons are used to help improve the available computational estimate of the uncertain and underresolved flow field of the hurricane and (b) this (imprecise) estimate of the hurricane flow field is leveraged to improve the distribution of the sensor balloons, which then better facilitates (a), etc. The control approach envisioned in this ambitious effort is a combination of (centrally computed) model predictive control for coordination at the largest scales, which is the focus of the present paper, coupled with a feedback control strategy (decentrally computed, on the balloons themselves), for smaller-scale corrections. Our work indicates that, following such an approach, certain target orbits of interest within the hurricane can be continuously sampled by some balloons, while others make repeated sweeps between the

  20. Phase transformation and its role in stabilizing simulated lead-laden sludge in aluminum-rich ceramics. (United States)

    Lu, Xingwen; Shih, Kaimin


    This study investigated the mechanisms of stabilizing lead-laden sludge by blending it into the production process of aluminum-rich ceramics, and quantitatively evaluated the prolonged leachability of the product phases. Sintering experiments were performed using powder mixtures of lead oxide and γ-alumina with different Pb/Al molar ratios within the temperature range of 600-1000 °C. By mixing lead oxide with γ-alumina at a Pb/Al molar ratio of 0.5, the formation of PbAl2O4 is initiated at 700 °C, but an effective formation was observed when the temperature was above 750 °C for a 3-h sintering time. The formation and decomposition of the intermediate phase, Pb9Al8O21, was detected in this system within the temperature range of 800-900 °C. When the lead oxide and γ-alumina mixture was sintered with a Pb/Al molar ratio of 1:12, the PbAl12O19 phase was found at 950 °C and effectively formed at 1000 °C. In this system, an intermediate phase Pb3(CO3)2(OH)2 was observed at the temperature range of 700-950 °C. Over longer leaching periods, both PbAl2O4 and PbAl12O19 were superior to lead oxide in immobilizing lead. Comparing the leaching results of PbAl2O4 and PbAl12O19 demonstrated the higher intrinsic resistance of PbAl12O19 against acid attack. To reduce metal mobility, this study demonstrated a preferred mechanism of stabilizing lead in the aluminate structures by adding metal-bearing waste sludge to the ceramic processing of aluminum-rich products.

  1. K Basin Hazard Analysis

    Energy Technology Data Exchange (ETDEWEB)

    PECH, S.H.


    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Final Safety Analysis Report. This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report.

  2. K Basins Hazard Analysis

    Energy Technology Data Exchange (ETDEWEB)

    WEBB, R.H.


    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Safety Analysis Report (HNF-SD-WM-SAR-062, Rev.4). This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report.

  3. Analysis of debris-flow recordings in an instrumented basin: confirmations and new findings

    Directory of Open Access Journals (Sweden)

    M. Arattano


    Full Text Available On 24 August 2006, a debris flow took place in the Moscardo Torrent, a basin of the Eastern Italian Alps instrumented for debris-flow monitoring. The debris flow was recorded by two seismic networks located in the lower part of the basin and on the alluvial fan, respectively. The event was also recorded by a pair of ultrasonic sensors installed on the fan, close to the lower seismic network. The comparison between the different recordings outlines particular features of the August 2006 debris flow, different from that of events recorded in previous years. A typical debris-flow wave was observed at the upper seismic network, with a main front abruptly appearing in the torrent, followed by a gradual decrease of flow height. On the contrary, on the alluvial fan the wave displayed an irregular pattern, with low flow depth and the main peak occurring in the central part of the surge both in the seismic recording and in the hydrographs. Recorded data and field evidences indicate that the surge observed on the alluvial fan was not a debris flow, and probably consisted in a water surge laden with fine to medium-sized sediment. The change in shape and characteristics of the wave can be ascribed to the attenuation of the surge caused by the torrent control works implemented in the lower basin during the last years.

  4. Magnetic field directed assembly of superstructures of ferrite-ferroelectric core-shell nanoparticles and studies on magneto-electric interactions

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasan, G., E-mail:; Sreenivasulu, G.; Benoit, Crystal [Physics Department, Oakland University, Rochester, Michigan 48309 (United States); Petrov, V. M. [Physics Department, Oakland University, Rochester, Michigan 48309 (United States); Institute of Electronic and Information Systems, Novgorod State University, Veliky Novgorod 173003 (Russian Federation); Chavez, F. [Chemistry Department, Oakland University, Rochester, Michigan 48309 (United States)


    Composites of ferromagnetic and ferroelectric are of interest for studies on mechanical strain mediated magneto-electric (ME) interactions and for useful technologies. Here, we report on magnetic-field-assisted-assembly of barium titanate (BTO)-nickel ferrite (NFO) core-shell particles into linear chains and 2D/3D arrays and measurements of ME effects in such assemblies. First, we synthesized the core-shell nano-particles with 50–600 nm BTO and 10–200 nm NFO by chemical self-assembly by coating the ferroic particles with complementary coupling groups and allowing them to self-assemble in the presence of a catalyst via the “click” reaction. The core-shell structure was confirmed with electron microscopy and scanning probe microscopy. We obtained superstructure of the core-shell particles by subjecting them to a magnetic field gradient that exerts an attractive force on the particles and align them toward the regions of high field strengths. At low particle concentration, linear chains were formed and they evolved into 2D and 3D arrays at high particle concentrations. Magnetoelectric characterization on unassembled films and assembled arrays has been performed through measurements of low-frequency ME voltage coefficient (MEVC) by subjecting the sample to a bias magnetic field and an ac magnetic field. The MEVC is higher for field-assembled samples than for unassembled films and is found to be sensitive to field orientation with a higher MEVC for magnetic fields parallel to the array direction than for magnetic fields perpendicular to the array. A maximum MEVC of 20 mV/cm Oe, one of the highest reported for any bulk nanocomposite, is measured across the array thickness. A model is provided for ME coupling in the superstructures of BTO-NFO particulate composites. First, we estimated the MEVC for a free-standing BTO-NFO core-shell particle and then extended the model to include an array of linear chains of the particles. The theoretical estimates are in

  5. Polymorphism of NaVO2F2: a P2₁/c superstructure with pseudosymmetry of P2₁/m in the subcell. (United States)

    Yu, Zi-Qun; Wang, Jing-Quan; Huang, Ya-Xi; Botis, Sanda M; Pan, Yuanming; Mi, Jin-Xiao


    The ADDSYM routine in the program PLATON [Spek (2015). Acta Cryst. C71, 9-18] has helped researchers to avoid structures of (metal-)organic compounds being reported in an unnecessarily low symmetry space group. However, determination of the correct space group may get more complicated in cases of pseudosymmetric inorganic compounds. One example is NaVO2F2, which was reported [Crosnier-Lopez et al. (1994). Eur. J. Solid State Inorg. Chem. 31, 957-965] in the acentric space group P2₁ based on properties but flagged by ADDSYM as (pseudo)centrosymmetric P2₁/m within default distance tolerances. Herein a systematic investigation reveals that NaVO2F2 exists in at least four polymorphs: P2₁, (I), P2₁/m, (II), P2₁/c, (III), and one or more low-temperature ones. The new centrosymmetric modification, (III), with the space group P2₁/c has a similar atomic packing geometry to phase (I), except for having a doubled c axis. The double-cell of phase (III) arises from atomic shifts from the glide plane c at (x, ¼, z). With increasing temperature, the number of observed reflections decreases. The odd l reflections gradually become weaker and, correspondingly, all atoms shift towards the glide plane, resulting in a gradual second-order transformation of (III) into high-temperature phase (II) (P2₁/m) at below 493 K. At least one first-order enantiotropic phase transition was observed below 139 K from both the single-crystal X-ray diffraction and the differential scanning calorimetry analyses. Periodic first-principles calculations within density functional theory show that both P2₁/c superstructure (III) and P2₁ substructure (I) are more stable than P2₁/m structure (II), and that P2₁/c superstructure (III) is more stable that P2₁ substructure (I).

  6. Synthesis, morphology and microstructure of pomegranate-like hematite ({alpha}-Fe{sub 2}O{sub 3}) superstructure with high coercivity

    Energy Technology Data Exchange (ETDEWEB)

    Tadic, Marin, E-mail: [Condensed Matter Physics Laboratory, Vinca Institute, University of Belgrade, P.O. Box 522, 11001 Belgrade (Serbia); Citakovic, Nada [Military Academy, Generala Pavla Jurisica Sturma 33, University of Belgrade, 11000 Belgrade (Serbia); Panjan, Matjaz [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Stanojevic, Boban [Vinca Institute of Nuclear Sciences, P.O. Box 522, 11001 Belgrade, University of Belgrade (Serbia); Markovic, Dragana [Condensed Matter Physics Laboratory, Vinca Institute, University of Belgrade, P.O. Box 522, 11001 Belgrade (Serbia); Jovanovic, Dorde [Center for Solid State Physics and New Materials, Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade (Serbia); Spasojevic, Vojislav [Condensed Matter Physics Laboratory, Vinca Institute, University of Belgrade, P.O. Box 522, 11001 Belgrade (Serbia)


    Highlights: Black-Right-Pointing-Pointer We found superior magnetic properties of the hematite ({alpha}-Fe{sub 2}O{sub 3}). Black-Right-Pointing-Pointer TEM and HRTEM images show a pomegranate-like superstructure. Black-Right-Pointing-Pointer Magnetic measurements display high coercivity H{sub C} = 4350 Oe at the room temperature. - Abstract: We found novel and superior magnetic properties of the hematite ({alpha}-Fe{sub 2}O{sub 3}) that originate from an internal microstructure of particles and strong inter-particle interactions between nanocrystal sub-units. The hematite particles were synthesized by thermal decomposition of iron (III) nitrate without any template or surfactant. The purity, size, crystallinity, morphology, microstructure and magnetic features of the as-prepared particles were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), Raman spectroscopy (RS) and SQUID magnetometry. An XRD study reveals a pure phase of {alpha}-Fe{sub 2}O{sub 3} whereas TEM shows {alpha}-Fe{sub 2}O{sub 3} spheres with a diameter of about 150 nm. RS also shows high quality and purity of the sample. Moreover, TEM and HRTEM images show a pomegranate-like superstructure and evidence that the spherical particles are composed of individual well-crystallized nanoparticle sub-units (self-assembled nanoparticles) with a size of about 20 nm. Magnetic measurements display hysteretic behavior at the room temperature with remanent magnetization M{sub r} = 0.731 emu/g, saturation magnetization M{sub S} = 6.83 emu/g and coercivity H{sub C} = 4350 Oe, as well as the Morin transition at T{sub M} = 261 K. These results and comparison with those in the literature reveal that the sample has extremely high coercivity. The magnetic properties of the sample are discussed in relation to morphology, internal microstructure, surface

  7. Preparation and properties of CeTe/sub 2/O/sub 6/ and ThTe/sub 2/O/sub 6/, compounds with a new superstructure of the fluorite type

    Energy Technology Data Exchange (ETDEWEB)

    Botto, I.L.; Baran, E.J. (La Plata Univ. Nacional (Argentina). Facultad de Ciencias Exactas)


    It is demonstrated that in the systems MO/sub 2//TeO/sub 2/ (with M = Ce, Th), treated in air and at 600 /sup 0/C, only phases of composition MTe/sub 2/O/sub 6/ are formed. They pertains to the cubic crystal system and constitutes a new type of fluorite-superstructure. Different aspects of its crystal chemistry are commented and also the infrared spectra are recorded and briefly discussed.

  8. The Aquitaine basin

    Energy Technology Data Exchange (ETDEWEB)

    Biteau, J.-J.; Le Marrec, A.; Le Vot, M.; Masset, J.-M.


    The Aquitaine Basin is located in the southwest of France, between the Gironde Arch in the north and the Pyrenean Mountain Chain in the south. It is a triangular-shaped domain, extending over 35000km{sup 2}. From north to south, six main geological provinces can be identified: (1) the Medoc Platform located south of the Gironde Arch; (2) the Parentis sub-basin; (3) the Landes Saddle; (4) the North Aquitaine Platform; (5) the foreland of the Pyrenees (also known as the Adour, Arzacq and Comminges sub-basins); and (6) the Pyrenean fold-and-thrust belt. Only the Parentis sub-basin, the foreland of the Pyrenean Chain and a minor part of the fold-and-thrust belt itself are proven hydrocarbon provinces. The Aquitaine Basin, in turn, is subdivided into four sub-basins - the Parentis, Adour-Arzacq, Tarbes and Comminges areas. The lozenge shape of these depocentres is related to the Hercynian tectonic framework of the Palaeozoic basement, reactivated during Early Cretaceous rifting. This rift phase aborted at the end of the Albian (prior to the development of an oceanic crust) in response to the beginning of the subduction of the Iberian plate under the European plate. During the Upper Cretaceous, continued subduction led to the creation of northwards-migrating flexural basins. In the Eocene, a paroxysmal phase of compression was responsible for the uplift of the Pyrenean Mountain Chain and for the thin-skinned deformation of the foreland basin. The resulting structuration is limited to the south by the internal core of the chain and to the north by the leading edge of the fold-and-thrust belt, where the Lacq and Meillon gas fields are located. Four main petroleum provinces have been exploited since the Second World War: (1) the oil-prone Parentis sub-basin and (2) salt ridges surrounding the Arzacq and Tarbes sub-basins; and (3) the gas-prone southern Arzacq sub-basin (including the external Pyrenean fold-and-thrust belt and the proximal foreland sub-basin) and (4

  9. Performance of an Anaerobic Baffled Filter Reactor in the Treatment of Algae-Laden Water and the Contribution of Granular Sludge

    Directory of Open Access Journals (Sweden)

    Yaqin Yu


    Full Text Available This study investigated the performance and stability of an anaerobic baffled filter reactor in the treatment of algae-laden water from Taihu Lake at several organic loading rates. The study also evaluated the capability of soft filler to train granule sludge and improve the anaerobic environment and sludge activity in the anaerobic baffled reactor (ABR, thereby enhancing the treatment efficiency. The ABR consisted of five rectangular compartments, each of which was 120 cm long, 80 cm wide, 80 cm high, and packed with soft filler. The anaerobic baffled filter reactor was found to be an efficient reactor configuration for the treatment of algae-laden water. The reactor was operated at an organic loading rate of 1.5 kg chemical oxygen demand (COD/(m3d and an ambient temperature of 30 °C; under these conditions, the COD removal efficiency was 80% and the biogas production rate was 293 mL/(Ld. Moreover, the soft filler increased the biomass retention time and decreased the rate at which solids were washed out from the reactor, promoting an improved spatial distribution of the microbial communities within the compartments. Methanoregula, Methanobacteriaceae, Methanosaeta, Methanoculleu, and Thermogymnomonas were the dominant archaeal species in each compartment during an operational period of approximately 100 days. The protease activity in the reactor decreased longitudinally down the reactor from Compartments 1 to 5, whereas the activity of coenzyme F420 increased. The soft filler played a key role in successfully treating algae-laden water with the anaerobic baffled filter reactor.

  10. The Triple Salt Sr14[Ta4N13][TaN4]O-A Nitridotantalate Oxide with 19-fold Rock Salt Superstructure. (United States)

    Wörsching, Matthias; Daiger, Martin; Hoch, Constantin


    A new structure motif in nitridometalate chemistry is the tetracatena-nitridotantalate anion [Ta4N13](19-). It occurs in the crystal structure of the triple salt Sr14[Ta4N13][TaN4]O (monoclinic, space group P21/c with a = 15.062(2) Å, b = 7.2484(6) Å, c = 24.266(3) Å, and β = 97.280(10)(o)) together with ortho-tantalate and isolated oxide anions. Synthesis followed a new approach with employment of Sr surplus and reductive conditions aimed at the preparation of subvalent compounds. The new structure type was established on the basis of single-crystal X-ray diffraction data and also Rietveld refinement. It is a complex superstructure of the rock salt structure type with Ta and Sr atoms forming the face-centered cubic packing and N and O atoms occupying 18/19 of the octahedral voids. We discuss structure and stability of the triple salt with respect to other known nitridometalates and the use of this triple salt for preparative access toward new metal-rich compounds in this field.

  11. On the crystal structure of Cr2N precipitates in high-nitrogen austenitic stainless steel. III. Neutron diffraction study on the ordered Cr2N superstructure. (United States)

    Lee, Tae-Ho; Kim, Sung-Joon; Shin, Eunjoo; Takaki, Setsuo


    The ordered structure of Cr(2)N precipitates in high-nitrogen austenitic steel was investigated utilizing high-resolution neutron powder diffractometry (HRPD). On the basis of the Rietveld refinement of neutron diffraction patterns, the ordered Cr2N superstructure was confirmed to be trigonal (space group P31m), with lattice parameters a=4.800 (4) and c=4.472 (5) A, as suggested in previous transmission electron microscopy studies [Lee, Oh, Han, Lee, Kim & Takaki (2005). Acta Cryst. B61, 137-144; Lee, Kim & Takaki (2006). Acta Cryst. B62, 190-196]. The occupancies of the N atoms in four crystallographic sites [1(a), 1(b), 2(d) and 2(c) Wyckoff sites] were determined to be 1.00 (5), 0.0, 0.74 (9) and 0.12 (3), respectively, reflecting a partial disordering of N atoms along the c axis. The position of the metal atom was specified to be x=0.346 (8) and z=0.244 (6), corresponding to a deviation from the ideal position (x=0.333 and z=0.250). This deviation caused the ((1/3 1/3)(0))-type superlattice reflection to appear. A comparison between the ideal and measured crystal structures of Cr2N was performed using a computer simulation of selected-area diffraction patterns.

  12. Sedimentary structures formed under water surface waves: examples from a sediment-laden flash flood observed by remote camer (United States)

    Froude, Melanie; Alexander, Jan; Cole, Paul; Barclay, Jenni


    On 13-14 October 2012, Tropical Storm Rafael triggered sediment-laden flash floods in the Belham Valley on Montserrat, West Indies. Rainfall was continuous for ~38 hours and intensity peaked at 48 mm/hr. Flow was strongly unsteady, turbulent with sediment concentrations varying up to hyperconcentrated. Time-lapse images captured at >1 frame per second by remote camera overlooking a surveyed valley section show the development of trains of water surface waves at multiple channel locations during different flow stages. Waves grew and diminished in height and remained stationary or migrated upstream. Trains of waves persisted for <5 minutes, until a single wave broke, sometimes initiating the breaking of adjacent waves within the train. Channel-wide surges (bores) propagating downstream with distinct turbulent flow fronts, were observed at irregular intervals during and up to 7 hours after peak stage. These bores are mechanically similar to breaking front tidal bores and arid flood bores, and resulted in a sudden increase in flow depth and velocity. When a bore front came into close proximity (within ~10 m) upstream of a train of water surface waves, the waves appeared to break simultaneously generating a localised surge of water upstream, that was covered by the bore travelling downstream. Those trains in which waves did not break during the passage of a bore temporarily reduced in height. In both cases, water surface waves reformed immediately after the surge in the same location. Deposits from the event, were examined in <4 m deep trenches ~0.5 km downstream of the remote camera. These contained laterally extensive lenticular and sheet-like units comprised of varying admixtures of sand and gravel that are attributed to antidunes, and associated transitions from upper-stage-plane-beds. Some of the structures are organised within concave upward sequences which contain downflow shifts between foreset and backset laminae; interpreted as trough fills from chute

  13. Consistent Large-Eddy Simulation of a Temporal Mixing Layer Laden with Evaporating Drops. Part 2; A Posteriori Modelling (United States)

    Leboissertier, Anthony; Okong'O, Nora; Bellan, Josette


    Large-eddy simulation (LES) is conducted of a three-dimensional temporal mixing layer whose lower stream is initially laden with liquid drops which may evaporate during the simulation. The gas-phase equations are written in an Eulerian frame for two perfect gas species (carrier gas and vapour emanating from the drops), while the liquid-phase equations are written in a Lagrangian frame. The effect of drop evaporation on the gas phase is considered through mass, species, momentum and energy source terms. The drop evolution is modelled using physical drops, or using computational drops to represent the physical drops. Simulations are performed using various LES models previously assessed on a database obtained from direct numerical simulations (DNS). These LES models are for: (i) the subgrid-scale (SGS) fluxes and (ii) the filtered source terms (FSTs) based on computational drops. The LES, which are compared to filtered-and-coarsened (FC) DNS results at the coarser LES grid, are conducted with 64 times fewer grid points than the DNS, and up to 64 times fewer computational than physical drops. It is found that both constant-coefficient and dynamic Smagorinsky SGS-flux models, though numerically stable, are overly dissipative and damp generated small-resolved-scale (SRS) turbulent structures. Although the global growth and mixing predictions of LES using Smagorinsky models are in good agreement with the FC-DNS, the spatial distributions of the drops differ significantly. In contrast, the constant-coefficient scale-similarity model and the dynamic gradient model perform well in predicting most flow features, with the latter model having the advantage of not requiring a priori calibration of the model coefficient. The ability of the dynamic models to determine the model coefficient during LES is found to be essential since the constant-coefficient gradient model, although more accurate than the Smagorinsky model, is not consistently numerically stable despite using DNS

  14. Modifed Great Basin Extent (Buffered) (United States)

    U.S. Geological Survey, Department of the Interior — Two different great basin perimeter files were intersected and dissolved using ArcGIS 10.2.2 to create the outer perimeter of the great basin for use modeling...

  15. Basin Hopping Graph

    DEFF Research Database (Denmark)

    Kucharik, Marcel; Hofacker, Ivo; Stadler, Peter


    Motivation RNA folding is a complicated kinetic process. The minimum free energy structure provides only a static view of the most stable conformational state of the system. It is insufficient to give detailed insights into the dynamic behavior of RNAs. A sufficiently sophisticated analysis...... of the folding free energy landscape, however, can provide the relevant information. Results We introduce the basin hopping graph (BHG) as a novel coarse-grained model of folding landscapes. Each vertex of the BHG is a local minimum, which represents the corresponding basin in the landscape. Its edges connect...

  16. Can Harry Potter still put a spell on us in a second language? An fMRI study on reading emotion-laden literature in late bilinguals. (United States)

    Hsu, Chun-Ting; Jacobs, Arthur M; Conrad, Markus


    In this fMRI study we contrasted emotional responses to literary reading in late bilinguals' first or second language. German participants with adequate English proficiency in their second language (L2) English read short text passages from Harry Potter books characterized by a "negative" or "positive" versus "neutral" emotional valence manipulation. Previous studies have suggested that given sufficient L2 proficiency, neural substrates involved in L1 versus L2 do not differ (Fabbro, 2001). On the other hand, the question of attenuated emotionality of L2 language processing is still an open debate (see Conrad, Recio, & Jacobs, 2011). Our results revealed a set of neural structures involved in the processing of emotion-laden literature, including emotion-related amygdala and a set of lateral prefrontal, anterior temporal, and temporo-parietal regions associated with discourse comprehension, high-level semantic integration, and Theory-of-Mind processing. Yet, consistent with post-scan emotion ratings of text passages, factorial fMRI analyses revealed stronger hemodynamic responses to "happy" than to "neutral" in bilateral amygdala and the left precentral cortex that were restricted to L1 reading. Furthermore, multivariate pattern analyses (MVPA) demonstrated better classifiability of differential patterns of brain activity elicited by passages of different emotional content in L1 than in L2 for the whole brain level. Overall, our results suggest that reading emotion-laden texts in our native language provides a stronger and more differentiated emotional experience than reading in a second language.

  17. Bioprinting of a mechanically enhanced three-dimensional dual cell-laden construct for osteochondral tissue engineering using a multi-head tissue/organ building system (United States)

    Shim, Jin-Hyung; Lee, Jung-Seob; Kim, Jong Young; Cho, Dong-Woo


    The aim of this study was to build a mechanically enhanced three-dimensional (3D) bioprinted construct containing two different cell types for osteochondral tissue regeneration. Recently, the production of 3D cell-laden structures using various scaffold-free cell printing technologies has opened up new possibilities. However, ideal 3D complex tissues or organs have not yet been printed because gel-state hydrogels have been used as the principal material and are unable to maintain the desired 3D structure due to their poor mechanical strength. In this study, thermoplastic biomaterial polycaprolactone (PCL), which shows relatively high mechanical properties as compared with hydrogel, was used as a framework for enhancing the mechanical stability of the bioprinted construct. Two different alginate solutions were then infused into the previously prepared framework consisting of PCL to create the 3D construct for osteochondral printing. For this work, a multi-head tissue/organ building system (MtoBS), which was particularly designed to dispense thermoplastic biomaterial and hydrogel having completely different rheology properties, was newly developed and used to bioprint osteochondral tissue. It was confirmed that the line width, position and volume control of PCL and alginate solutions were adjustable in the MtoBS. Most importantly, dual cell-laden 3D constructs consisting of osteoblasts and chondrocytes were successfully fabricated. Further, the separately dispensed osteoblasts and chondrocytes not only retained their initial position and viability, but also proliferated up to 7 days after being dispensed.

  18. Single-basined choice

    NARCIS (Netherlands)

    Bossert, W.; Peters, H.J.M.


    Single-basined preferences generalize single-dipped preferences by allowing for multiple worst elements. These preferences have played an important role in areas such as voting, strategy-proofness and matching problems. We examine the notion of single-basinedness in a choice-theoretic setting. In co

  19. 上海城市交通政策的顶层设计思考%Superstructure Design for Shanghai's Urban Transport Policy

    Institute of Scientific and Technical Information of China (English)



    首先分析了城市交通与城市发展及可持续发展的关系,指出包括城市规划和城市交通规划内的城市管理能力是实现人们享受较高的城市交通方便性(城市机动性的提高),同时避免城市交通的外部性及对城市环境和全球气候环境的影响的重要因素.正是由于有比较明确的城市交通政策导向,面临城市快速经济发展和城市面积的扩展,与国内一些曾经希望适应小汽车发展的城市相比,上海城市交通状况和城市环境质量具有明显的优势.为此,对上海的城市交通政策的作用进行了系统的分析,指出在新的发展形势下一些曾经十分有效的政策其作用正在降低,人们必须对上海城市交通政策的顶层设计进行调整,将上海建设成为世界绿色城市交通之都.%The paper analyzes the fundamental relationship between urban transport and sustainable urban development in China' s fast urbanizing context. It points to the importance of urban management capacity to ensure people' s enjoyment of convenience and mobility without exerting negative externalities on physical environment, public health and global climate change. It is evident that urban planning and urban comprehensive transport management is the key components of urban management capacity. Compared with other mega cities in China such as Beijing, Guangzhou and Shenzhen, the performance of Shanghai' s urban transport system is superior in terms of quality of service and environmental impacts. This was achieved because Shanghai has maintained a clear urban transport policy orientation for more than 20 years, given the rapid economic development, fast urban expansion and continued rise in personal incomes. There has been consensus among all stakeholders involved in urban transport planning, management and infrastructure construction that Shanghai cannot afford endless growth of car ownership and superstructure of urban transport policy must be

  20. Self-assembly of multiferroic core-shell particulate nanocomposites through DNA-DNA hybridization and magnetic field directed assembly of superstructures

    Directory of Open Access Journals (Sweden)

    Gollapudi Sreenivasulu


    Full Text Available Multiferroic composites of ferromagnetic and ferroelectric phases are of importance for studies on mechanical strain mediated coupling between the magnetic and electric subsystems. This work is on DNA-assisted self-assembly of superstructures of such composites with nanometer periodicity. The synthesis involved oligomeric DNA-functionalized ferroelectric and ferromagnetic nanoparticles, 600 nm BaTiO3 (BTO and 200 nm NiFe2O4 (NFO, respectively. Mixing BTO and NFO particles, possessing complementary DNA sequences, resulted in the formation of ordered core-shell heteronanocomposites held together by DNA hybridization. The composites were imaged by scanning electron microscopy and scanning microwave microscopy. The presence of heteroassemblies along with core-shell architecture is clearly observed. The reversible nature of the DNA hybridization allows for restructuring the composites into mm-long linear chains and 2D-arrays in the presence of a static magnetic field and ring-like structures in a rotating-magnetic field. Strong magneto-electric (ME coupling in as-assembled composites is evident from static magnetic field H induced polarization and low-frequency magnetoelectric voltage coefficient measurements. Upon annealing the nanocomposites at high temperatures, evidence for the formation of bulk composites with excellent cross-coupling between the electric and magnetic subsystems is obtained by H-induced polarization and low-frequency ME voltage coefficient. The ME coupling strength in the self-assembled composites is measured to be much stronger than in bulk composites with randomly distributed NFO and BTO prepared by direct mixing and sintering.

  1. Características ultra-estruturais do nó sinoatrial de rato Wistar Superstructural features of the wistar strain male rats' sinoatrial node (SAN

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Mandarim de Lacerda


    Full Text Available As características ultra-estruturais do nó sinoatrial (NSA de 5 ratos machos da variedade Wistar, com 3 meses de idade, foram estudadas por meio de microscopia eletrônica de transmissão (MET. Fragmento pequeno, contendo a região do NSA e área adjacente do átrio direito do coração, foi retirado e fixado em glutaraldeído 2,5% e processado de acordo com técnica convencional para MET. A morfologia do nó sinoatrial de ratos é semelhante a de outros mamíferos. O NSA é uma estrutura anatômica independente do miocárdio atrial, constituído por células típicas (miócitos nodais, células de transição e, principalmente, células nodais imersos em matriz extracelular, na qual predominam fibras colágenas, fibroblastos e nervosThe superstructural features of five Wistar strain male rats' sinoatrial node (SAN at 3-mo-old were studied through transmission electron microscopy (TEM. Small fragments with the regions containing the SAN were cut off, fixed in glutaraldehyde 2.5% and processed according to the conventional technique for TEM. The morphology of the sinoatrial node of the rats is similar as found in other mammals. The SAN is an independent anatomic structure of the atrial myocardial, constituted of typical cells (nodal myocytes, transition cells and nodal cells principally immersed in the extra cellular matrix where collagen fibers, fibroblasts and nerve predominate

  2. Highly Efficient Retention of Polysulfides in "Sea Urchin"-Like Carbon Nanotube/Nanopolyhedra Superstructures as Cathode Material for Ultralong-Life Lithium-Sulfur Batteries. (United States)

    Chen, Tao; Cheng, Baorui; Zhu, Guoyin; Chen, Renpeng; Hu, Yi; Ma, Lianbo; Lv, Hongling; Wang, Yanrong; Liang, Jia; Tie, Zuoxiu; Jin, Zhong; Liu, Jie


    Despite high theoretical energy density, the practical deployment of lithium-sulfur (Li-S) batteries is still not implemented because of the severe capacity decay caused by polysulfide shuttling and the poor rate capability induced by low electrical conductivity of sulfur. Herein, we report a novel sulfur host material based on "sea urchin"-like cobalt nanoparticle embedded and nitrogen-doped carbon nanotube/nanopolyhedra (Co-NCNT/NP) superstructures for Li-S batteries. The hierarchical micromesopores in Co-NCNT/NP can allow efficient impregnation of sulfur and block diffusion of soluble polysulfides by physical confinement, and the incorporation of embedded Co nanoparticles and nitrogen doping (∼4.6 at. %) can synergistically improve the adsorption of polysulfides, as evidenced by beaker cell tests. Moreover, the conductive networks of Co-NCNT/NP interconnected by nitrogen-doped carbon nanotubes (NCNTs) can facilitate electron transport and electrolyte infiltration. Therefore, the specific capacity, rate capability, and cycle stability of Li-S batteries are significantly enhanced. As a result, the Co-NCNT/NP based cathode (loaded with 80 wt % sulfur) delivers a high discharge capacity of 1240 mAh g(-1) after 100 cycles at 0.1 C (based on the weight of sulfur), high rate capacity (755 mAh g(-1) at 2.0 C), and ultralong cycling life (a very low capacity decay of 0.026% per cycle over 1500 cycles at 1.0 C). Remarkably, the composite cathode with high areal sulfur loading of 3.2 mg cm(-2) shows high rate capacities and stable cycling performance over 200 cycles.

  3. 船舶上层建筑端部实板厚疲劳试验研究%Real-thickness fatigue strength test of the ship superstructure end

    Institute of Scientific and Technical Information of China (English)

    任慧龙; 崔兵兵; 冯国庆; 成兵


    In order to research the fatigue characteristics of the ship superstructure end, the real⁃thickness four⁃point bending model tests were designed and actualized. The number of cycles to failure in the fatigue tests were ob⁃tained under different stress levels. The mid⁃value S-N curve and P-S-N curve were drawn through the fixed⁃slope maximum likehood method. The fatigue strength of the position was caculated and compared by testing P-S-N curve and the E curve of CCS codes. The research showed that the S-N curve obtained from fatigue tests can offer a reference for the design and analysis of ships in practice.%为研究船体上层建筑端部的疲劳特性,设计和实施了实板厚四点弯曲疲劳模型试验。获得疲劳试验中不同应力水平下的疲劳失效循环次数,并采用定斜率极大似然法拟合应力水平-疲劳失效循环次数得到中值S-N曲线和P-S-N曲线。分别采用试验P-S-N曲线和CCS规范E曲线计算和比较研究该部位的疲劳强度。结果表明,试验得到的S-N曲线可为实船设计和分析提供参考。

  4. Frontier petroleum basins of Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Keith, J.F. Jr.; Perez, V.E.


    The frontier basins of Colombia with hydrocarbon potential are numerous, have varying geological histories, and are in different stages of exploration development. In this paper, sedimentary or structural basins are classified as frontier petroleum basins if commercial discoveries of hydrocarbons are lacking, if the basin has not attained a high degree of exploration development, or if a new play concept has been perceived or developed for a portion of a mature exploration basin. Using these criteria for classification, the authors discuss the Cauca-Patia Choco-Pacifico, and Lower Magdalena basin complexes; the Cordillera Oriental foreland basin; and the Cesar-Rancheria, Sabana, and Amazonas basins. A comprehensive geological and structural setting of each of these frontier basins will be presented. The depositional and tectonic evolution of the basins will be highlighted, and the play concepts for each will be inventoried, catalogued, and categorized as to whether they are theoretical or established. The discussion of the available plays in each of these basins will include the main play concept elements of reservoirs traps, seals, source rocks, maturation, and timing. When detailed data permit, the reservoir and trap geometry will be presented.

  5. Direct Numerical Simulation of Transitional Multicomponent-Species Gaseous and Multicomponent-Liquid Drop-Laden Mixing (United States)

    Selle, Laurent C.; Bellan, Josette


    organization depend on the initial gas temperature, this being due to the drop/turbulence coupling. The vapor-composition mean molar mass and standard deviation distributions strongly correlate with the initial liquid-composition PDF; such a correlation only exists for the magnitude of the mean but not for that of the standard deviation. Unlike in pre-transitional situations, regions of large composition standard deviation no longer necessarily coincide with regions of large mean molar mass. The kinetic energy, rotational and composition characteristics, and dissipation are liquid specific and the variation among liquids is amplified with increasing free-stream gas temperature. Eulerian and Lagrangian statistics of gas-phase quantities show that the different. Observation framework may affect the perception of the flow characteristics. The gas composition, of which the first four moments are calculated, is shown to be close to, but distinct from a SGPDF. The PDF of the scalar dissipation rate is calculated for drop-laden layers and is shown to depart more significantly from the typically assumed Gaussian in gaseous flows than experimentally measured gaseous scalar dissipation rates, this being attributed to the increased heterogeneity due to drop/flow interactions.

  6. Direct numerical simulation of gaseous mixing layers laden with multicomponent-liquid drops: liquid-specific effects (United States)

    Le Clercq, Patrick C.; Bellan, Josette


    A representation of multicomponent-liquid (MC-liquid) composition as a linear combination of two single-Gamma probability distribution functions (PDFs) is used to describe a large number of MC-liquid drops evaporating in a gas flow. The PDF, called the double-Gamma PDF, depends on the molar mass. The gas-phase conservation equations are written in an Eulerian frame and the drops are described in a Lagrangian frame. Gas conservation equations for mass, momentum, species and energy are combined with differential conservation equations for the first four moments of the gas-composition PDF and coupled to the perfect gas equation of state. Source terms in all conservation equations account for the gas/drop interaction. The drop governing equations encompass differential conservation statements for position, mass, momentum, energy and four moments of the liquid-composition PDF. Simulations are performed for a three-dimensional mixing layer whose lower stream is initially laden with drops colder than the surrounding gas. Initial perturbations excite the layer to promote the double pairing of its four initial spanwise vortices to an ultimate vortex. During the layer evolution, the drops heat and evaporate. The results address the layer evolution, and the state of the gas and drops when layers reach a momentum-thickness maximum past the double vortex pairing. Of interest is the influence of the liquid composition on the development of the vortical features of the flow, on the vortical state reached after the second pairing, and on the gas temperature and composition. The MC-liquid simulations are initiated with a single-Gamma PDF composition so as to explore the development of the double-Gamma PDF. Examination of equivalent simulations with n-decane, diesel and three kerosenes as the liquid, permits assessment of the single-species versus the MC-liquid aspect, and of mixture composition specific effects. Global layer growth and global rotational characteristics are

  7. Natural frequency of regular basins (United States)

    Tjandra, Sugih S.; Pudjaprasetya, S. R.


    Similar to the vibration of a guitar string or an elastic membrane, water waves in an enclosed basin undergo standing oscillatory waves, also known as seiches. The resonant (eigen) periods of seiches are determined by water depth and geometry of the basin. For regular basins, explicit formulas are available. Resonance occurs when the dominant frequency of external force matches the eigen frequency of the basin. In this paper, we implement the conservative finite volume scheme to 2D shallow water equation to simulate resonance in closed basins. Further, we would like to use this scheme and utilizing energy spectra of the recorded signal to extract resonant periods of arbitrary basins. But here we first test the procedure for getting resonant periods of a square closed basin. The numerical resonant periods that we obtain are comparable with those from analytical formulas.

  8. Fabrication of viable centimeter-sized 3D tissue constructs with microchannel conduits for improved tissue properties through assembly of cell-laden microbeads. (United States)

    Luo, Houyong; Chen, Maiqin; Wang, Xiu; Mei, Yang; Ye, Zhaoyang; Zhou, Yan; Tan, Wen-Song


    Bottom-up approaches have emerged as a new philosophy in tissue engineering, enabling precise control over tissue morphogenesis at the cellular level. We previously prepared large bone-like tissues using cell-laden microbeads (microtissues) by following a modular approach to ensure cell viability. However, a long-term culture of such avascular macroscopic tissues (macrotissues) has not been evaluated. In the present study, microtissues were fabricated by cultivating human fibroblasts on Cytopore-2 microbeads in spinner flasks for 16 days. We then examined the long-term perfusion culture for macrotissues. Specifically, following assembly in a perfusion chamber for 15 days, cell death was found to be prominent at a depth of 500 µm from the surface of macrotissues towards the interior, suggesting that there was a new mass transfer limit leading to cell death instead of tissue maturation. Subsequently, we developed a strategy by incorporating microchannel structures in centimeter-sized tissue constructs to promote mass transport. By installing glass rods (1 mm diameter, 1 mm wall-to-wall spacing) in the perfusion chamber, stable microchannel architectures were introduced during the microtissue assembly process. Based on live/dead assay and scanning electron microscopy (SEM), these channelled macrotissues (length × diameter, 1.6 × 2.0 cm) demonstrated high cell viability and compact packing of microbeads. Comparative biochemical analysis further suggested a more homogeneous spatial distribution of cells and extracellular matrix (ECM) in the channelled macrotissues than in solid ones. Viable 3D large tissues can therefore be prepared by assembling cell-laden microbeads in conjunction with microchannel carving, meeting clinical needs in tissue repair.

  9. Engineering zonal cartilaginous tissue by modulating oxygen levels and mechanical cues through the depth of infrapatellar fat pad stem cell laden hydrogels. (United States)

    Luo, Lu; O'Reilly, Adam R; Thorpe, Stephen D; Buckley, Conor T; Kelly, Daniel J


    Engineering tissues with a structure and spatial composition mimicking those of native articular cartilage (AC) remains a challenge. This study examined if infrapatellar fat pad-derived stem cells (FPSCs) can be used to engineer cartilage grafts with a bulk composition and a spatial distribution of matrix similar to the native tissue. In an attempt to mimic the oxygen gradients and mechanical environment within AC, FPSC-laden hydrogels (either 2 mm or 4 mm in height) were confined to half of their thickness and/or subjected to dynamic compression (DC). Confining FPSC-laden hydrogels was predicted to accentuate the gradient in oxygen tension through the depth of the constructs (higher in the top and lower in the bottom), leading to enhanced glycosaminoglycan (GAG) and collagen synthesis in 2 mm high tissues. When subjected to DC alone, both GAG and collagen accumulation increased within 2 mm high unconfined constructs. Furthermore, the dynamic modulus of constructs increased from 0.96 MPa to 1.45 MPa following the application of DC. There was no synergistic benefit of coupling confinement and DC on overall levels of matrix accumulation; however in all constructs, irrespective of their height, the combination of these boundary conditions led to the development of engineered tissues that spatially best resembled native AC. The superficial region of these constructs mimicked that of native tissue, staining weakly for GAG, strongly for type II collagen, and in 4 mm high tissues more intensely for proteoglycan 4 (lubricin). This study demonstrated that FPSCs respond to joint-like environmental conditions by producing cartilage tissues mimicking native AC. Copyright © 2016 John Wiley & Sons, Ltd.

  10. 有蓄能的联供系统超结构优化配置%Superstructure-based Optimal Planning of Cogeneration Systems With Storage

    Institute of Scientific and Technical Information of China (English)

    肖小清; 阚伟民; 杨允; 张士杰; 肖云汉


    In this paper, the storage was introduced into a superstructure-based optimal planning mixed integer linear programming (MILP) model of cogeneration systems The model can achieve simultaneous optimization of system structure and operation as well as simultaneous optimization of all equipment including storage. At the same time the branch and bound method combined with the simplex method was used as a solution algorithm. Through a case study, the validity and effectiveness of the proposed model and the method were verified. The computational results also indicate that, the introduction of storages in cogeneration systems reduces the capacities of other refrigeration equipment; under time of use electricity rates, storage enhances the system flexibility and economic and energy saving can be obtained through removing some of the strong coupling relationship between cooling/heating demands and generators. The optimal operation strategies of storage are different in typical days, which depend on electricity price, energy demands et al.%将蓄能装置引入到基于超结构方法的分布式联供系统优化配置混合整数线性规划模型之中,所得模型可实现系统结构和运行同步优化、各设备与蓄能装置同时优化,采用分枝定界法结合单纯形算法实现对模型的求解.通过研究案例,验证了计算模型和求解方法的可行性和有效性.计算结果亦表明,联供系统中引入蓄能装置可以减小系统内其它制冷设备的容量;在分时电价体系下引入蓄能装置可以部分解除冷热负荷与发电机组之间的强耦合关系,使联供系统运行更灵活,并降低供能成本和能耗;在不同的典型日内蓄能装置的优化运行规律不同,取决于电价、负荷需求等.

  11. Intracontinental basins and strong earthquakes

    Institute of Scientific and Technical Information of China (English)

    邓起东; 高孟潭; 赵新平; 吴建春


    The September 17, 1303 Hongtong M=8 earthquake occurred in Linfen basin of Shanxi down-faulted basin zone. It is the first recorded M=8 earthquake since the Chinese historical seismic records had started and is a great earthquake occurring in the active intracontinental basin. We had held a Meeting of the 700th Anniversary of the 1303 Hongtong M=8 Earthquake in Shanxi and a Symposium on Intracontinental Basins and Strong Earthquakes in Taiyuan City of Shanxi Province on September 17~18, 2003. The articles presented on the symposium discussed the relationships between active intracontinental basins of different properties, developed in different regions, including tensional graben and semi-graben basins in tensile tectonic regions, compression-depression basins and foreland basins in compressive tectonic regions and pull-apart basins in strike-slip tectonic zones, and strong earthquakes in China. In this article we make a brief summary of some problems. The articles published in this special issue are a part of the articles presented on the symposium.

  12. Estancia Basin dynamic water budget.

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Richard P.


    The Estancia Basin lies about 30 miles to the east of Albuquerque, NM. It is a closed basin in terms of surface water and is somewhat isolated in terms of groundwater. Historically, the primary natural outlet for both surface water and groundwater has been evaporation from the salt lakes in the southeastern portion of the basin. There are no significant watercourses that flow into this basin and groundwater recharge is minimal. During the 20th Century, agriculture grew to become the major user of groundwater in the basin. Significant declines in groundwater levels have accompanied this agricultural use. Domestic and municipal use of the basin groundwater is increasing as Albuquerque population continues to spill eastward into the basin, but this use is projected to be less than 1% of agricultural use well into the 21st Century. This Water Budget model keeps track of the water balance within the basin. The model considers the amount of water entering the basin and leaving the basin. Since there is no significant surface water component within this basin, the balance of water in the groundwater aquifer constitutes the primary component of this balance. Inflow is based on assumptions for recharge made by earlier researchers. Outflow from the basin is the summation of the depletion from all basin water uses. The model user can control future water use within the basin via slider bars that set values for population growth, water system per-capita use, agricultural acreage, and the types of agricultural diversion. The user can also adjust recharge and natural discharge within the limits of uncertainty for those parameters. The model runs for 100 years beginning in 1940 and ending in 2040. During the first 55 years model results can be compared to historical data and estimates of groundwater use. The last 45 years are predictive. The model was calibrated to match to New Mexico Office of State Engineer (NMOSE) estimates of aquifer storage during the historical period by

  13. 乌苏大桥主桥上部结构设计与计算%Design and Calculation of Superstructure of Main Bridge of Wusu Bridge

    Institute of Scientific and Technical Information of China (English)

    康晋; 肖海珠; 徐伟


    The main bridge of the Wusu Bridge is a single pylon and single cable plane cablestayed bridge with span arrangement (140+140) m and with a structural system of rigid fixity of the pylon, pier and girder. A summarized account of the design and calculation of the superstructure of the bridge is presented herewith. The main girder of the bridge is a composite girder with long cantilevers, the central part of the girder is designed as a two-cell and single-box steel girder and the steel cantilever at each side of the girder is the variable depth I-beam and is provided wiht a trough stringer at the far side, which are all topped with 25 cm thick concrete deck slabs connected with the girder via shearing studs. The part of the main girder close to the pylon is designed as a prestressed concrete box girder to facilitate the fixity of the girder with the pylon. The pylon is the single column pylon, 117 m in height. The stay cables, made up of low relaxation galvanized high strength parallel steel wire strands, are of the harp pattern cable plane arranged in the central alignment of the bridge deck. The finite element software MIDAS Civil 2006 and the SCDS programme are employed to calculate and analyze structure of the bridge. The results of the calculation and analysis indicate that the static, stability and dynamic characteristics of the bridge can meet the requirements in the relevant codes.%乌苏大桥主桥为独塔单索面斜拉桥,跨径布置为(140+140) m,采用塔、墩、梁固结体系,综述该桥上部结构设计与计算.主梁为带大挑臂的钢箱结合梁,中间钢箱梁采用单箱双室截面,两侧钢挑臂为变高度工字形梁,挑臂端部设槽形小纵梁;混凝土桥面板厚25 cm,与钢梁通过剪力钉连接;塔根部主梁采用预应力混凝土箱梁,以方便与桥塔固结;桥塔采用独柱式塔,高117 m;斜拉索为竖琴形中央平行索面布置,采用低松弛镀锌高强度平行钢丝束.采用有限元软件MIDAS Civil

  14. Direct numerical simulation of particle-laden turbulent channel flows with two- and four-way coupling effects: budgets of Reynolds stress and streamwise enstrophy

    Energy Technology Data Exchange (ETDEWEB)

    Dritselis, Chris D, E-mail: [Mechanical Engineering Department, University of Thessaly, Pedion Areos, 38334 Volos (Greece)


    The budgets of the Reynolds stress and streamwise enstrophy are evaluated through direct numerical simulations for the turbulent particle-laden flow in a vertical channel with momentum exchange between the two phases. The influence of the dispersed particles on the budgets is examined through a comparison of the particle-free and the particle-laden cases at the same Reynolds number of Re{sub b} = 5600 based on the bulk fluid velocity and the distance between the channel walls. Results are obtained for particle ensembles with four response times in simulations with and without streamwise gravity and inter-particle collisions at average mass (volume) fractions of 0.2 (2.7 × 10{sup −5}) and 0.5 (6.8 × 10{sup −5}). The particle feedback force on the flow of the carrier phase is modeled by a point-force approximation (PSIC-method). It is shown that all the terms in the budgets of the Reynolds stress components are decreased in the presence of particles. The level of reduction depends on the particle response time and it is higher under the effects of gravity and inter-particle collisions. A considerable reduction in all the terms of the streamwise enstrophy budget is also observed. In particular, all production mechanisms, and mainly vortex stretching, are inhibited in the particulate flows and thus the production of streamwise vorticity is significantly damped. A further insight into the direct particle effects on the fluid turbulence is provided by analyzing in detail the fluid–fluid, fluid–particle and particle–particle correlations, and the spectra of the fluid–particle energy exchange rate. The present results indicate that the turbulence production, dissipation and pressure–strain term are generally large quantities, but their summation is relatively small and comparable to the fluid–particle direct energy exchange rate. Consequently, the particle contribution can potentially increase or decrease the fluctuating fluid velocities and eventually

  15. K-Basins design guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Roe, N.R.; Mills, W.C.


    The purpose of the design guidelines is to enable SNF and K Basin personnel to complete fuel and sludge removal, and basin water mitigation by providing engineering guidance for equipment design for the fuel basin, facility modifications (upgrades), remote tools, and new processes. It is not intended to be a purchase order reference for vendors. The document identifies materials, methods, and components that work at K Basins; it also Provides design input and a technical review process to facilitate project interfaces with operations in K Basins. This document is intended to compliment other engineering documentation used at K Basins and throughout the Spent Nuclear Fuel Project. Significant provisions, which are incorporated, include portions of the following: General Design Criteria (DOE 1989), Standard Engineering Practices (WHC-CM-6-1), Engineering Practices Guidelines (WHC 1994b), Hanford Plant Standards (DOE-RL 1989), Safety Analysis Manual (WHC-CM-4-46), and Radiological Design Guide (WHC 1994f). Documents (requirements) essential to the engineering design projects at K Basins are referenced in the guidelines.


    Energy Technology Data Exchange (ETDEWEB)

    Ahsan R. Choudhuri


    A passive control technology utilizing elliptic co-flow to control the particle flinging and particle dispersion in a particle (coal)-laden flow was investigated using experimental and numerical techniques. Preferential concentration of particles occurs in particle-laden jets used in pulverized coal burner and causes uncontrollable NO{sub x} formation due to inhomogeneous local stoichiometry. This particular project was aimed at characterizing the near-field flow behavior of elliptic coaxial jets. The knowledge gained from the project will serve as the basis of further investigation on fluid-particle interactions in an asymmetric coaxial jet flow-field and thus is important to improve the design of pulverized coal burners where non-homogeneity of particle concentration causes increased NO{sub x} formation.

  17. Geologic Basin Boundaries (Basins_GHGRP) GIS Layer (United States)

    U.S. Environmental Protection Agency — This is a coverage shapefile of geologic basin boundaries which are used by EPA's Greenhouse Gas Reporting Program. For onshore production, the "facility" includes...

  18. The Amazon basin in transition. (United States)

    Davidson, Eric A; de Araújo, Alessandro C; Artaxo, Paulo; Balch, Jennifer K; Brown, I Foster; C Bustamante, Mercedes M; Coe, Michael T; DeFries, Ruth S; Keller, Michael; Longo, Marcos; Munger, J William; Schroeder, Wilfrid; Soares-Filho, Britaldo S; Souza, Carlos M; Wofsy, Steven C


    Agricultural expansion and climate variability have become important agents of disturbance in the Amazon basin. Recent studies have demonstrated considerable resilience of Amazonian forests to moderate annual drought, but they also show that interactions between deforestation, fire and drought potentially lead to losses of carbon storage and changes in regional precipitation patterns and river discharge. Although the basin-wide impacts of land use and drought may not yet surpass the magnitude of natural variability of hydrologic and biogeochemical cycles, there are some signs of a transition to a disturbance-dominated regime. These signs include changing energy and water cycles in the southern and eastern portions of the Amazon basin.

  19. 用于超结构换热器网络热计算和网络综合的显式解%An Explicit Solution for Thermal Calculation and Synthesis of Superstructure Heat Exchanger Networks

    Institute of Scientific and Technical Information of China (English)

    陈德珍; 杨杉杉; 罗行; 温卿云; 马虎根


    For the optimal design of a heat exchanger network,the inlet and outlet stream temperatures of each heat exchanger in the network should be known.An explicit analytical solution of stream temperatures of an arbitrary connected heat exchanger network was introduced,which is suitable for the thermal calculation of heat exchanger networks.For the heat exchanger network synthesis,this solution was further developed and coupled with the stage-wise superstructure heat exchanger networks.The new calculation procedure reduced the computer memory requirement dramatically.On the basis of this solution,a mathematical model for synthesis of heat exchanger networks with genetic algorithm was formulated,which is always feasible and no iteration is needed.Two examples were calculated with the proposed approach and better results were obtained.

  20. Numerical simulation of two-way coupling mechanism in particle-laden turbulent flow based on one-dimensional turbulence model (United States)

    Sun, Guangyuan; Lignell, David; Hewson, John; Gin, Craig


    We present three algorithms (type-I, type-C and type-IC) for Lagrangian particle transport within the context of the one-dimensional turbulence (ODT) approach. ODT is a stochastic model that captures the full range of length and time scales and provides statistical information on fine-scale turbulent-particle mixing and transport at low computational cost. Two of the particle transport algorithms are new as is an algorithm to provide two-way momentum and energy coupling between the particle and carrier phases. Using these methods we investigate particle-laden turbulent jet flow. In contrast to other previous particle implementation in ODT, the two new methods allow the particles to interact with multiple eddies simultaneously and evolve the particle phase continuously, and therefore are able to accurately capture turbulent mixing and fluctuation seen by inertial particles in ODT. Simulation results are compared with experimental data including the effect of two particle Stokes numbers (St = 3.6 and 10.8). Turbulence modification, particle number density PDFs and particle velocity evolution are presented.

  1. Microvesicles released from fat-laden cells promote activation of hepatocellular NLRP3 inflammasome: A pro-inflammatory link between lipotoxicity and non-alcoholic steatohepatitis (United States)

    Bocca, Claudia; Foglia, Beatrice; Benetti, Elisa; Novo, Erica; Chiazza, Fausto; Rogazzo, Mara; Fantozzi, Roberto; Povero, Davide; Sutti, Salvatore; Bugianesi, Elisabetta; Feldstein, Ariel E.; Albano, Emanuele; Collino, Massimo; Parola, Maurizio


    Non-Alcoholic Fatty Liver Disease (NAFLD) is a major form of chronic liver disease in the general population in relation to its high prevalence among overweight/obese individuals and patients with diabetes type II or metabolic syndrome. NAFLD can progress to steatohepatitis (NASH), fibrosis and cirrhosis and end-stage of liver disease but mechanisms involved are still incompletely characterized. Within the mechanisms proposed to mediate the progression of NAFLD, lipotoxicity is believed to play a major role. In the present study we provide data suggesting that microvesicles (MVs) released by fat-laden cells undergoing lipotoxicity can activate NLRP3 inflammasome following internalization by either cells of hepatocellular origin or macrophages. Inflammasome activation involves NF-kB-mediated up-regulation of NLRP3, pro-caspase-1 and pro-Interleukin-1, then inflammasome complex formation and Caspase-1 activation leading finally to an increased release of IL-1β. Since the release of MVs from lipotoxic cells and the activation of NLRP3 inflammasome have been reported to occur in vivo in either clinical or experimental NASH, these data suggest a novel rational link between lipotoxicity and increased inflammatory response. PMID:28249038

  2. Treatment of metal-laden hazardous wastes with advanced clean coal technology by-products. Quarterly report, November 1994--February 1995

    Energy Technology Data Exchange (ETDEWEB)



    This second quarterly report describes work during the second three months of the University of Pittsburgh`s (Pitt`s) project on the {open_quotes}Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.{close_quotes} Participating with Pitt on this project are Dravo Lime Company (DLC), Mill Service, Inc. (MSI) and the Center for Hazardous Materials Research (CHMR). The report describes the activities of the project team during the reporting period. The principal work has focussed upon the acquisition of by-product samples and their initial analysis. Other efforts during the second quarter have been directed toward identifying the first hazardous waste samples and preparing for their treatment and analysis. Relatively little data has yet been collected. Major presentation of technical details and data will appear for the first time in the third quarterly report. The activity on the project during the second quarter of Phase One, as presented in the following sections, has fallen into seven areas: (1) Acquiring by-products, (2) Analyzing by-products, (3) Identifying, analyzing and treating suitable hazardous wastes, (4) Carrying out the quality assurance/quality control program, (5) Developing background, and (6) Initiating public relations

  3. 多沙河流水库泥沙研究展望%Research Prospects of Reservoir Sedimentation in Sediment -laden River

    Institute of Scientific and Technical Information of China (English)

    郜国明; 谈广鸣; 李涛


    多沙河流上修建水库对于水资源匮乏地区的水资源高效利用与维持河流健康具有重要的意义。针对多沙河流水库泥沙研究的水库淤积、水库调度、水库泥沙处理与利用以及水库模拟手段等方面进行总结和分析,指出各方面的研究难点及面临的主要问题,并对黄河水库泥沙研究中的问题进行展望。%It is important for water resource efficient use in water scarcity areas and maintaining river health to build reservoirs in the sediment-laden river . This paper generalizes and analyses reservoir sedimentation , reservoir regulation , sediment treatment and utilization , reservoir simulation in reservoir sediment study , with to point out the difficulty and main problems in the study . At last , a prospect has been carried out in the reservoir sedimentation study . Results of this research will clarify the thinking of the Yellow River sediment reservoirs study in future to promote the reservoir sediment study of the Yellow River .

  4. Direct numerical simulation of particle-laden turbulent channel flows with two- and four-way coupling effects: models of terms in the Reynolds stress budgets (United States)

    Dritselis, Chris D.


    In the first part of this study (Dritselis 2016 Fluid Dyn. Res. 48 015507), the Reynolds stress budgets were evaluated through point-particle direct numerical simulations (pp-DNSs) for the particle-laden turbulent flow in a vertical channel with two- and four-way coupling effects. Here several turbulence models are assessed by direct comparison of the particle contribution terms to the budgets, the dissipation rate, the pressure-strain rate, and the transport rate with the model expressions using the pp-DNS data. It is found that the models of the particle sources to the equations of fluid turbulent kinetic energy and dissipation rate cannot represent correctly the physics of the complex interaction between turbulence and particles. A relatively poor performance of the pressure-strain term models is revealed in the particulate flows, while the algebraic models for the dissipation rate of the fluid turbulence kinetic energy and the transport rate terms can adequately reproduce the main trends due to the presence of particles. Further work is generally needed to improve the models in order to account properly for the momentum exchange between the two phases and the effects of particle inertia, gravity and inter-particle collisions.

  5. Treatment of metal-laden hazardous wastes with advanced clean coal technology by-products. Quarterly report, May 1995--August 1995

    Energy Technology Data Exchange (ETDEWEB)



    This fourth quarterly report describes work done during the fourth three-month period of the University of Pittsburgh`s project on the {open_quotes}Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.{close_quote} Participating with the university on this project are Dravo Lime Company, Mill Service, Inc., and the Center for Hazardous Materials Research. This report describes the activities of the project team during the reporting period. The principal work has focussed upon the production of six sets of samples with high water content for solidification testing and the mixing of five dry samples for solidification testing by the Proctor method. Twenty-eight day compressive strengths are reported for five of the six sets of samples with high water content. The report also discusses completion of the format of the database and the inclusion in it of all data collected to date. Special reports presented during the quarter include the Continuation Application, a News Release, and modification to the Test Plan. Work is progressing on the NEPA report and the Topical Report. The activity on the project during the fourth quarter of Phase one, as presented in the following sections, has fallen into six major areas: (1) Completion of by-product evaluations, (2) Completion of analyses of six wastes, (3) Initiation of eleven solidification tests, (4) Continued extraction and extract analysis of solidified samples, (5) Development of the database, and (6) Production of reports.

  6. Trip report Rainwater Basin Nebraska (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is a summary a trip to Rainwater Basin Wetland Management District in 1991, and focuses on the hydrology and soil habitat types. It is part of the...

  7. Allegheny County Basin Outlines Map (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This basins dataset was created to initiate regional watershed approaches with respect to sewer rehabilitation. If viewing this description on the Western...

  8. All-in-one bioprobe devised with hierarchical-ordered magnetic NiCo2O4 superstructure for ultrasensitive dual-readout immunosensor for logic diagnosis of tumor marker. (United States)

    Dai, Hong; Gong, Lingshan; Zhang, Shupei; Xu, Guifang; Li, Yilin; Hong, Zhensheng; Lin, Yanyu


    A new enzyme-free all-in-one bioprobe, consisted of hematin decorated magnetic NiCo2O4 superstructure (ATS-MNS-Hb), was designed for ultrasensitive photoelectrochemical and electrochemical dual-readout immunosensing of carcinoembryonic antigen (CEA) on carbon nanohorns (CNH) support. Herein, the MNS, possessed hierarchical-ordered structure, good porosity and magnetism, acted as nanocarrier to absorb abundant Hb molecular after functionalization, providing a convenient collection means by magnetic control as well as enhanced dual-readout sensing performances. CNH superstructures were employed as support to immobilize abounding captured antibodies, and then as-designed dual mode bioprobe, covalent binding with secondary antibody of CEA, was introduced for ultrasensitive detection of CEA by sandwich immunosensing. Photoelectrochemical response originated from plentiful hematin molecular, a excellent photosensitizer with good visible light harvesting efficiency, absorbed by functionalized porous MNS. The resultant concentration dependant linear calibration range was from 10 fg/mL to 1 ng/mL with ultralow detection limit of 10 fg/mL. For electrochemical process, catalase-like property of MNS was validated, moreover, MNS-Hb hybrid exhibited much higher mimic enzyme catalytic activity and evidently amplified electrocatalytic signal, performing a wide dynamic linear range from 1 ng/mL to 40 ng/mL with low detection limit of 1 ng/mL. Additionally, due to the improved accuracy of dual signals detection, the exact diagnoses of serum samples were gotten by operating resulting dual signals with AND logic system. This work demonstrated the promising application of MNS in developing ultrasensitive, cost-effective and environment friendly dual-readout immunosensor and accurate diagnoses strategy for tumor markers.

  9. 77 FR 45653 - Yakima River Basin Conservation Advisory Group; Yakima River Basin Water Enhancement Project... (United States)


    ... Bureau of Reclamation Yakima River Basin Conservation Advisory Group; Yakima River Basin Water... on the structure, implementation, and oversight of the Yakima River Basin Water Conservation Program... of the Water Conservation Program, including the applicable water conservation guidelines of...


    Energy Technology Data Exchange (ETDEWEB)

    Robert Caldwell


    Vast quantities of natural gas are entrapped within various tight formations in the Rocky Mountain area. This report seeks to quantify what proportion of that resource can be considered recoverable under today's technological and economic conditions and discusses factors controlling recovery. The ultimate goal of this project is to encourage development of tight gas reserves by industry through reducing the technical and economic risks of locating, drilling and completing commercial tight gas wells. This report is the fourth in a series and focuses on the Wind River Basin located in west central Wyoming. The first three reports presented analyses of the tight gas reserves and resources in the Greater Green River Basin (Scotia, 1993), Piceance Basin (Scotia, 1995) and the Uinta Basin (Scotia, 1995). Since each report is a stand-alone document, duplication of language will exist where common aspects are discussed. This study, and the previous three, describe basin-centered gas deposits (Masters, 1979) which contain vast quantities of natural gas entrapped in low permeability (tight), overpressured sandstones occupying a central basin location. Such deposits are generally continuous and are not conventionally trapped by a structural or stratigraphic seal. Rather, the tight character of the reservoirs prevents rapid migration of the gas, and where rates of gas generation exceed rates of escape, an overpressured basin-centered gas deposit results (Spencer, 1987). Since the temperature is a primary controlling factor for the onset and rate of gas generation, these deposits exist in the deeper, central parts of a basin where temperatures generally exceed 200 F and drill depths exceed 8,000 feet. The abbreviation OPT (overpressured tight) is used when referring to sandstone reservoirs that comprise the basin-centered gas deposit. Because the gas resources trapped in this setting are so large, they represent an important source of future gas supply, prompting studies

  11. Water Accounting from Ungauged Basins (United States)

    Bastiaanssen, W. G.; Savenije, H.


    Water scarcity is increasing globally. This requires a more accurate management of the water resources at river basin scale and understanding of withdrawals and return flows; both naturally and man-induced. Many basins and their tributaries are, however, ungauged or poorly gauged. This hampers sound planning and monitoring processes. While certain countries have developed clear guidelines and policies on data observatories and data sharing, other countries and their basin organization still have to start on developing data democracies. Water accounting quantifies flows, fluxes, stocks and consumptive use pertaining to every land use class in a river basin. The objective is to derive a knowledge base with certain minimum information that facilitates decision making. Water Accounting Plus (WA+) is a new method for water resources assessment reporting ( While the PUB framework has yielded several deterministic models for flow prediction, WA+ utilizes remote sensing data of rainfall, evaporation (including soil, water, vegetation and interception evaporation), soil moisture, water levels, land use and biomass production. Examples will be demonstrated that show how remote sensing and hydrological models can be smartly integrated for generating all the required input data into WA+. A standard water accounting system for all basins in the world - with a special emphasis on data scarce regions - is under development. First results of using remote sensing measurements and hydrological modeling as an alternative to expensive field data sets, will be presented and discussed.

  12. Principal component analysis to assess the efficiency and mechanism for enhanced coagulation of natural algae-laden water using a novel dual coagulant system. (United States)

    Ou, Hua-Se; Wei, Chao-Hai; Deng, Yang; Gao, Nai-Yun; Ren, Yuan; Hu, Yun


    A novel dual coagulant system of polyaluminum chloride sulfate (PACS) and polydiallyldimethylammonium chloride (PDADMAC) was used to treat natural algae-laden water from Meiliang Gulf, Lake Taihu. PACS (Aln(OH)mCl3n-m-2k(SO4)k) has a mass ratio of 10 %, a SO4 (2-)/Al3 (+) mole ratio of 0.0664, and an OH/Al mole ratio of 2. The PDADMAC ([C8H16NCl]m) has a MW which ranges from 5 × 10(5) to 20 × 10(5) Da. The variations of contaminants in water samples during treatments were estimated in the form of principal component analysis (PCA) factor scores and conventional variables (turbidity, DOC, etc.). Parallel factor analysis determined four chromophoric dissolved organic matters (CDOM) components, and PCA identified four integrated principle factors. PCA factor 1 had significant correlations with chlorophyll-a (r=0.718), protein-like CDOM C1 (0.689), and C2 (0.756). Factor 2 correlated with UV254 (0.672), humic-like CDOM component C3 (0.716), and C4 (0.758). Factors 3 and 4 had correlations with NH3-N (0.748) and T-P (0.769), respectively. The variations of PCA factors scores revealed that PACS contributed less aluminum dissolution than PAC to obtain equivalent removal efficiency of contaminants. This might be due to the high cationic charge and pre-hydrolyzation of PACS. Compared with PACS coagulation (20 mg L(-1)), the removal of PCA factors 1, 2, and 4 increased 45, 33, and 12 %, respectively, in combined PACS-PDADMAC treatment (0.8 mg L(-1) +20 mg L(-1)). Since PAC contained more Al (0.053 g/1 g) than PACS (0.028 g/1 g), the results indicated that PACS contributed less Al dissolution into the water to obtain equivalent removal efficiency.

  13. Prechlorination of algae-laden water: The effects of transportation time on cell integrity, algal organic matter release, and chlorinated disinfection byproduct formation. (United States)

    Qi, Jing; Lan, Huachun; Liu, Ruiping; Miao, Shiyu; Liu, Huijuan; Qu, Jiuhui


    The prechlorination-induced algal organic matter (AOM) released from Microcystis aeruginosa (M. aeruginosa) cells has been reported to serve as a source of precursors for chlorinated disinfection byproducts (DBPs). However, previous studies have mainly focused on the precursors either extracted directly from the cell suspension or derived immediately after algal suspension prechlorination. This study aims to investigate the impacts of water transportation time after algal suspension prechlorination on cell integrity, AOM release, and DBP formation during the dissolved phase chlorination. The damage to cell integrity after prechlorination was indicated to depend not only on chlorine dose but also on transportation time. The highest dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) values were observed at 2 mg/L chlorine preoxidation before transportation, but were obtained at 0.4 mg/L chlorine after 480-min simulated transportation. The variation of DON with transportation time was indicated to be mainly influenced by the small molecular weight nitrogenous organic compounds, such as amino acids. Additionally, formation of the corresponding chlorinated carbonaceous disinfection byproducts (C-DBPs) and nitrogenous disinfection byproducts (N-DBPs) during the dissolved phase chlorination showed the same variation tendency as DOC and DON respectively. The highest C-DBP (98.4 μg/L) and N-DBP (5.5 μg/L) values were obtained at 0.4 mg/L chlorine preoxidation after 480-min simulated transportation. Therefore, when prechlorination is applied for algae-laden water pretreatment, not only chlorine dose but also transportation time needs to be considered with regard to their effects on cell integrity, AOM release, and chlorinated DBP formation.

  14. Geology, exploration status of Uruguay's sedimentary basins

    Energy Technology Data Exchange (ETDEWEB)

    Goso, C.; Santa Ana, H. de (Administracion Nacional de Combustibles, Alcohol y Portland (Uruguay))


    This article attempts to present the geological characteristics and tectonic and sedimentary evolution of Uruguayan basins and the extent to which they have been explored. Uruguay is on the Atlantic coast of South America. The country covers about 318,000 sq km, including offshore and onshore territories corresponding to more than 65% of the various sedimentary basins. Four basins underlie the country: the Norte basin, the Santa Lucia basin, the offshore Punta del Este basin, and the offshore-onshore Pelotas-Merin basin. The Norte basin is a Paleozoic basin while the others are Mesozoic basins. Each basin has been explored to a different extent, as this paper explains.

  15. Testing for Basins of Wada. (United States)

    Daza, Alvar; Wagemakers, Alexandre; Sanjuán, Miguel A F; Yorke, James A


    Nonlinear systems often give rise to fractal boundaries in phase space, hindering predictability. When a single boundary separates three or more different basins of attraction, we say that the set of basins has the Wada property and initial conditions near that boundary are even more unpredictable. Many physical systems of interest with this topological property appear in the literature. However, so far the only approach to study Wada basins has been restricted to two-dimensional phase spaces. Here we report a simple algorithm whose purpose is to look for the Wada property in a given dynamical system. Another benefit of this procedure is the possibility to classify and study intermediate situations known as partially Wada boundaries.

  16. The Central European Permian Basins; Rheological and structural controls on basin history and on inter-basin connectivity

    NARCIS (Netherlands)

    Smit, Jeroen; van Wees, Jan-Diederik; Cloetingh, Sierd


    We analyse the relative importance of the major crustal-scale fault zones and crustal architecture in controlling basin formation, deformation and the structural connections between basins. The North and South Permian Basins of Central Europe are usually defined by the extend of Rotliegend sedimenta

  17. Origin of the earth's ocean basins (United States)

    Frey, H.


    The earth's original ocean basins are proposed to be mare-type basins produced 4 billion y.a. by the flux of asteroid-sized objects responsible for the lunar mare basins. Scaling upward from the observed number of lunar basins for the greater capture cross-section and impact velocity of the earth indicates that at least 50% of an original global crust would have been converted to basin topography. These basins were flooded by basaltic liquids in times short compared to the isostatic adjustment time for the basin. The modern crustal dichotomy (60% oceanic, 40% continental crust) was established early in the history of the earth, making possible the later onset of plate tectonic processes. These later processes have subsequently reworked, in several cycles, principally the oceanic parts of the earth's crust, changing the configuration of the continents in the process. Ocean basins (and oceans themselves) may be rare occurrences on planets in other star systems.

  18. WATSTORE Stream Flow Basin Characteristics File (United States)

    U.S. Geological Survey, Department of the Interior — The Stream Flow Basin Characteristics file contains information about the drainage basins of selected USGS gaging stations. Data elements of this file were converted...

  19. H-Area Seepage Basins

    Energy Technology Data Exchange (ETDEWEB)

    Stejskal, G.


    During the third quarter of 1990 the wells which make up the H-Area Seepage Basins (H-HWMF) monitoring network were sampled. Laboratory analyses were performed to measure levels of hazardous constituents, indicator parameters, tritium, nonvolatile beta, and gross alpha. A Gas Chromatograph Mass Spectrometer (GCMS) scan was performed on all wells sampled to determine any hazardous organic constituents present in the groundwater. The primary contaminants observed at wells monitoring the H-Area Seepage Basins are tritium, nitrate, mercury, gross alpha, nonvolatile beta, trichloroethylene (TCE), tetrachloroethylene, lead, cadmium, arsenic, and total radium.

  20. 超高车辆-桥梁上部结构撞击力的工程计算方法%Engineering Calculation Method for Collision Force Between Over-height Truck and Bridge Superstructure

    Institute of Scientific and Technical Information of China (English)

    陆新征; 卢啸; 张炎圣; 何水涛


    为了弥补中国在超高车辆撞击桥梁上部结构领域研究的不足,完善其工程设计方法,在超高车辆撞击桥梁上部结构的事故案例调查和精细化有限元分析的基础上,提出了超高车辆-桥梁上部结构撞击的简化计算模型,建立了简化模型的微分方程组,利用数值试验的方法确定了简化模型中的部分参数,从而得出简化计算模型的撞击荷载;为了满足工程设计的需要,在简化模型的基础上提出了形式简单的撞击力设计公式,以表格的形式给出了设计公式中基本参数的主要取值,并将简化模型和设计公式的计算结果与有限元结果进行了比较.结果表明:根据简化模型和设计公式计算得到的撞击荷载与精细有限元模型的计算结果吻合较好,且偏于安全,可为工程设计提供参考.%In order to make up the insufficient research on the collisions between over-high truck and bridge superstructure in China and to improve the corresponding engineering design method,based on the accident investigation and high precision finite element analysis on the collision between over-high truck and bridge superstructure, a simplified computational model was proposed to calculate the collision between over-high truck and bridge superstructure. The differential equations of the simplified model were established and parts of factors in the model were determined by numerical experiments. Therefore, the collision load can be computed by the simplified model. Furthermore, in order to satisfy the engineering application, design formula of collision force with simple form based on the simplified model was proposed, and the basic factor values in the design formula were given in a table. Results show that the design formula results and the simplified model results are in good agreement with finite element results, and they are relatively safe. So they can provide reference for engineering design.

  1. Study of Superstructure of Two-Lane Suspension Bridge with Integral Cross Section%整体式断面双车道索道桥上部结构研究

    Institute of Scientific and Technical Information of China (English)

    景天虎; 马小龙; 刘均利; 莫时旭


    为寻求整体式断面双车道索道桥上部结构的可行布置形式,采用考虑索梁组合结构几何非线性的空间有限元法,对几种桥面系构造方案的结构特性进行研究。研究结果表明:对于双车道索道桥,活载单车道偏载是比活载双车道同时偏载更为不利的荷载工况;在活载作用下,整个桥面系在横桥向不再保持线性变位;简单地采用横向线性扩展车道宽度的措施来构造双车道索道桥上部结构方案,将很难满足结构横倾稳定性要求;主索在横桥向的不同分布是影响索道桥结构抗扭能力的最主要因素;在桥面中央布置适量的主索对优化横梁内力分布状况是有益的。%To find a rational superstructure configuration for two‐lane suspension bridges with integral cross section ,the spatial finite element method taking into consideration of non‐linearity of cable‐beam composite structure was employed and the structural features of different bridge deck system schemes were studied .The results of the study demonstrate that for a two‐lane suspension bridge ,the load case of single‐lane unbalanced live loads is much more unfavorable than that of two‐lane unbalanced live load .Under the action of live loads ,the overall bridge deck system no longer exhibits linear variation in the transverse bridge direction .To form the superstructure of the two‐lane suspension bridge simply via linear expansion of traffic lanes in the transverse direc‐tion is hard to meet the demands of the transverse overturning stability of the structure .How to arrange the main cables in the transverse direction is the key concerning the torsional capacity of a suspension bridge .Installing a proper amount of main cables in the central part of the bridge deck is good to optimize the internal force distribution in the floor beams .

  2. BASIN: Beowulf Analysis Symbolic INterface (United States)

    Vesperini, Enrico; Goldberg, David M.; McMillan, Stephen L. W.; Dura, James; Jones, Douglas


    BASIN (Beowulf Analysis Symbolic INterface) is a flexible, integrated suite of tools for multiuser parallel data analysis and visualization that allows researchers to harness the power of Beowulf PC clusters and multi-processor machines without necessarily being experts in parallel programming. It also includes general tools for data distribution and parallel operations on distributed data for developing libraries for specific tasks.

  3. Basin bifurcation in quasiperiodically forced systems

    Energy Technology Data Exchange (ETDEWEB)

    Feudel, U.; Witt, A.; Grebogi, C. [Institut fuer Physik, Universitaet Potsdam, Am Neuen Palais, PF 601553, D-14415, Potsdam (Germany); Lai, Y. [Departments of Physics and Astronomy and of Mathematics, The University of Kansas, Lawrence, Kansas 66045 (United States); Grebogi, C. [Institute for Plasma Research, University of Maryland, College Park, Maryland 20742 (United States)


    In this paper we study quasiperiodically forced systems exhibiting fractal and Wada basin boundaries. Specifically, by utilizing a class of representative systems, we analyze the dynamical origin of such basin boundaries and we characterize them. Furthermore, we find that basin boundaries in a quasiperiodically driven system can undergo a unique type of bifurcation in which isolated {open_quotes}islands{close_quotes} of basins of attraction are created as a system parameter changes. The mechanism for this type of basin boundary bifurcation is elucidated. {copyright} {ital 1998} {ital The American Physical Society}

  4. Minimizing the Risk of Disease Transmission in Emergency Settings: Novel In Situ Physico-Chemical Disinfection of Pathogen-Laden Hospital Wastewaters.

    Directory of Open Access Journals (Sweden)

    Emanuele Sozzi

    Full Text Available The operation of a health care facility, such as a cholera or Ebola treatment center in an emergency setting, results in the production of pathogen-laden wastewaters that may potentially lead to onward transmission of the disease. The research presented here evaluated the design and operation of a novel treatment system, successfully used by Médecins Sans Frontières in Haiti to disinfect CTC wastewaters in situ, eliminating the need for road haulage and disposal of the waste to a poorly-managed hazardous waste facility, thereby providing an effective barrier to disease transmission through a novel but simple sanitary intervention. The physico-chemical protocols eventually successfully treated over 600 m3 of wastewater, achieving coagulation/flocculation and disinfection by exposure to high pH (Protocol A and low pH (Protocol B environments, using thermotolerant coliforms as a disinfection efficacy index. In Protocol A, the addition of hydrated lime resulted in wastewater disinfection and coagulation/flocculation of suspended solids. In Protocol B, disinfection was achieved by the addition of hydrochloric acid, followed by pH neutralization and coagulation/flocculation of suspended solids using aluminum sulfate. Removal rates achieved were: COD >99%; suspended solids >90%; turbidity >90% and thermotolerant coliforms >99.9%. The proposed approach is the first known successful attempt to disinfect wastewater in a disease outbreak setting without resorting to the alternative, untested, approach of 'super chlorination' which, it has been suggested, may not consistently achieve adequate disinfection. A basic analysis of costs demonstrated a significant saving in reagent costs compared with the less reliable approach of super-chlorination. The proposed approach to in situ sanitation in cholera treatment centers and other disease outbreak settings represents a timely response to a UN call for onsite disinfection of wastewaters generated in such

  5. Minimizing the Risk of Disease Transmission in Emergency Settings: Novel In Situ Physico-Chemical Disinfection of Pathogen-Laden Hospital Wastewaters. (United States)

    Sozzi, Emanuele; Fabre, Kerline; Fesselet, Jean-François; Ebdon, James E; Taylor, Huw


    The operation of a health care facility, such as a cholera or Ebola treatment center in an emergency setting, results in the production of pathogen-laden wastewaters that may potentially lead to onward transmission of the disease. The research presented here evaluated the design and operation of a novel treatment system, successfully used by Médecins Sans Frontières in Haiti to disinfect CTC wastewaters in situ, eliminating the need for road haulage and disposal of the waste to a poorly-managed hazardous waste facility, thereby providing an effective barrier to disease transmission through a novel but simple sanitary intervention. The physico-chemical protocols eventually successfully treated over 600 m3 of wastewater, achieving coagulation/flocculation and disinfection by exposure to high pH (Protocol A) and low pH (Protocol B) environments, using thermotolerant coliforms as a disinfection efficacy index. In Protocol A, the addition of hydrated lime resulted in wastewater disinfection and coagulation/flocculation of suspended solids. In Protocol B, disinfection was achieved by the addition of hydrochloric acid, followed by pH neutralization and coagulation/flocculation of suspended solids using aluminum sulfate. Removal rates achieved were: COD >99%; suspended solids >90%; turbidity >90% and thermotolerant coliforms >99.9%. The proposed approach is the first known successful attempt to disinfect wastewater in a disease outbreak setting without resorting to the alternative, untested, approach of 'super chlorination' which, it has been suggested, may not consistently achieve adequate disinfection. A basic analysis of costs demonstrated a significant saving in reagent costs compared with the less reliable approach of super-chlorination. The proposed approach to in situ sanitation in cholera treatment centers and other disease outbreak settings represents a timely response to a UN call for onsite disinfection of wastewaters generated in such emergencies, and the

  6. Successor Characteristics of the Mesozoic and Cenozoic Songliao Basins

    Institute of Scientific and Technical Information of China (English)

    LI Zhongquan; Timothy KUSKY; YING Danlin; GUO Xiaoyu; LI Hongkui


    The Songliao basin is a complex successor basin that was initiated in the Mesozoic and experienced multiple periods of reactivation. Based on seismic and drilling data, as well as regional geologic research, we suggest that the Songliao basin contains several different successor basins resting on top of Carboniferous-Permian folded strata forming the basement to the Songliao basin. These basins include the Triassic-Mid Jurassic Paleo-foreland basin, the Late Jurassic-Early Cretaceous downfaulted basin, and an early Cretaceous depressed basin (since the Denglouku Group). This paper presents a systematic study of the basin-mountain interactions, and reveals that there are different types of prototype basin at different geologic times. These prototype basins sequentially superimposed and formed the large Songliao basin. Discovery of the Triassic-early Middle Jurassic paleo-foreland basin fills a Triassic-early Middle Jurassic gap in the geologic history of the Songliao basin. The paleoforeland basin, downfaulted basin, and depressed thermal subsidence basin all together represent the whole Mesozoic-Cenozoic geologic history and deformation of the Songliao basin. Discovery of the Triassic-early Middle Jurassic paleo-foreland basin plays an important role both for deep natural gas exploration and the study of basin-mountain coupling in north China and eastern China in general. This example gives dramatic evidence that we should give much more attention to the polyphase tectonic evolution of related basins for the next phase of exploration and study.

  7. Geodynamics of the Sivas Basin (Turkey): from a forearc basin to a retroarc foreland basin (United States)

    Legeay, Etienne; Ringenbach, Jean-Claude; Kergaravat, Charlie; Callot, Jean-Paul; Mohn, Geoffroy; Kavak, Kaan


    Anatolia records the consumption of several oceanic basins, from the Northern Neotethys domain, by north-dipping subduction until the end of Mesozoic. The associated obduction event occurred during Campanian, from North to South and from Greece to Oman, leading to the emplacement of ophiolite thrust sheets and associated ophiolitic mélange. In particular, the Sivas Basin in Eastern Anatolia is located at the boundary between the Kırsehir block to the East, Pontide arc to the North and Tauride Platform to the South, sutured by ophiolitic belts. The Sivas Basin formed a Tertiary fold-and-thrust belt, which exhibits mainly north verging thrust in Paleogene deposits, and South verging thrust in oligo-miocene sequence. To understand the northern verging thrust above south verging obduction, it is necessary to zoom out of the basin, and include a set of processes that affect the eastern Anatolia. This study aims to characterize the structural and sedimentary evolution of the Sivas Basin, based on a fieldwork approach, coupled to the interpretation of subsurface data, thermochronology and biostratigraphy. The Sivas Basin was initiated in a forearc setting relatively to the subduction of the Inner-Tauride Ocean while the associated ophiolites are obducted onto the northern passive margin of the Tauride margin. Early Maastrichtian to Paleocene deposits are represented by carbonate platforms located on ophiolitic highs, passing to turbidites and olistostomes toward the North. The early Eocene sediments, mainly composed of ophiolitic clasts, are deposited on a regional unconformity marked along the southern margin of the basin by incisions in response to the emergence of north-verging thrust. The middle Eocene sediments, intensively folded by northward thrusting, are mostly represented by flysch type deposits (olistostromes, mass-flows and turbidites). The onset of the compression is related to the initiation of the Taurus shortening in a retroarc situation, in response to

  8. 连续梁拱组合桥梁上部结构施工关键技术研究%On the Key Construction Technology of the Superstructure of Continuous Beam-arch Combination Bridge

    Institute of Scientific and Technical Information of China (English)



    随着我国社会水平的提升,经济步伐的推进,我国的交通事业也在这个过程中得到了较大程度的发展。其中,连续梁拱组合桥梁是我国现今桥梁建设中非常重要的一个类型,近年来,已经有很多城市利用该种类型建设桥梁。本文将深入地研究分析连续梁拱组合桥梁上部结构施工关键技术,同时提出相应的政策建议。%With the ascension of social level and the progress of economic, the transportation industry of China also gets a larger degree of development in the process. The combination bridge of continuous beam-arc is a very important type in the current bridge construction of China. In recent years, there are many cities using this type to construct bridges. This paper deeply researches and analyzes the key construction technology of the superstructure of continuous beam-arch combination bridge and puts forward the related policy suggestions.

  9. RE{sub 13}Pd{sub 25+x}Zn{sub 28-x} (RE = Y, Ho-Lu). A 4 x 4 x 4 tungsten superstructure with short Pd/Zn dumbbells as structural motif

    Energy Technology Data Exchange (ETDEWEB)

    Gerke, Birgit; Hoffmann, Rolf-Dieter; Niehaus, Oliver; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie


    The rare earth-based zinc compounds RE{sub 13}Pd{sub 25+x}Zn{sub 28-x} (RE = Y, Ho-Lu) were synthesized from the elements in sealed niobium ampoules with a maximum reaction temperature of 1470 K followed by different annealing sequences. The structures of all compounds were refined from single crystal X-ray diffraction data, indicating substantial Zn/Pd mixing on one 8c and one 24g zinc site. Exemplarily, the homogeneity range of the solid solution Yb{sub 13}Pd{sub 25+x}Zn{sub 28-x} was manifested from samples of different starting compositions and five single crystal data sets. The RE{sub 13}Pd{sub 25+x}Zn{sub 28-x} structures are cubic, space group I anti 43m with lattice parameters ranging from 1295 to 1307 pm, as a function of the rare earth element and the Zn/Pd mixing. Hierarchically, one can derive the RE{sub 13}Pd{sub 25+x}Zn{sub 28-x} structures from the simple bcc packing. A group-subgroup scheme was developed for this new 4 x 4 x 4 tungsten superstructure which shows vacancy ordering and dumbbell formation. Temperature dependent magnetic susceptibility measurements show diamagnetism for a Lu{sub 13}Pd{sub 29}Zn{sub 24} sample and Curie-Weiss paramagnetism for Tm{sub 13}Pd{sub 29}Zn{sub 24} down to 3 K.


    Energy Technology Data Exchange (ETDEWEB)

    William Goddard; Peter Meulbroek; Yongchun Tang; Lawrence Cathles III


    In the next decades, oil exploration by majors and independents will increasingly be in remote, inaccessible areas, or in areas where there has been extensive shallow exploration but deeper exploration potential may remain; areas where the collection of data is expensive, difficult, or even impossible, and where the most efficient use of existing data can drive the economics of the target. The ability to read hydrocarbon chemistry in terms of subsurface migration processes by relating it to the evolution of the basin and fluid migration is perhaps the single technological capability that could most improve our ability to explore effectively because it would allow us to use a vast store of existing or easily collected chemical data to determine the major migration pathways in a basin and to determine if there is deep exploration potential. To this end a the DOE funded a joint effort between California Institute of Technology, Cornell University, and GeoGroup Inc. to assemble a representative set of maturity and maturation kinetic models and develop an advanced basin model able to predict the chemistry of hydrocarbons in a basin from this input data. The four year project is now completed and has produced set of public domain maturity indicator and maturation kinetic data set, an oil chemistry and flash calculation tool operable under Excel, and a user friendly, graphically intuitive basin model that uses this data and flash tool, operates on a PC, and simulates hydrocarbon generation and migration and the chemical changes that can occur during migration (such as phase separation and gas washing). The DOE Advanced Chemistry Basin Model includes a number of new methods that represent advances over current technology. The model is built around the concept of handling arbitrarily detailed chemical composition of fluids in a robust finite-element 2-D grid. There are three themes on which the model focuses: chemical kinetic and equilibrium reaction parameters, chemical

  11. Salt Lake in Chaidamu Basin

    Institute of Scientific and Technical Information of China (English)



    Chaidamu Basin(柴达木盆地) is in the west of China. It covers an area(地区) of 220,000 square kilometres(平方公里). The number of salt lakes(盐湖) is more than twenty in it. Chaerhan(察尔汗) Salt Lake is the largest in this area. If you get here, you will find that in the lake there is no water but a thick layer(层) of salt. You can walk in it without difficulty, and cars can come and go across it. The thickest layer of salt in this basin is about fifty metres thick. People tried their best to use the salt to build house...

  12. Basin stability in delayed dynamics (United States)

    Leng, Siyang; Lin, Wei; Kurths, Jürgen


    Basin stability (BS) is a universal concept for complex systems studies, which focuses on the volume of the basin of attraction instead of the traditional linearization-based approach. It has a lot of applications in real-world systems especially in dynamical systems with a phenomenon of multi-stability, which is even more ubiquitous in delayed dynamics such as the firing neurons, the climatological processes, and the power grids. Due to the infinite dimensional property of the space for the initial values, how to properly define the basin’s volume for delayed dynamics remains a fundamental problem. We propose here a technique which projects the infinite dimensional initial state space to a finite-dimensional Euclidean space by expanding the initial function along with different orthogonal or nonorthogonal basis. A generalized concept of basin’s volume in delayed dynamics and a highly practicable calculating algorithm with a cross-validation procedure are provided to numerically estimate the basin of attraction in delayed dynamics. We show potential applicabilities of this approach by applying it to study several representative systems of biological or/and physical significance, including the delayed Hopfield neuronal model with multistability and delayed complex networks with synchronization dynamics.

  13. Great Basin geoscience data base (United States)

    Raines, Gary L.; Sawatzky, Don L.; Connors, Katherine A.


    This CD-ROM serves as the archive for 73 digital GIS data set for the Great Basin. The data sets cover Nevada, eastern California, southeastern Oregon, southern Idaho, and western Utah. Some of the data sets are incomplete for the total area. On the CD-ROM, the data are provided in three formats, a prototype Federal Data Exchange standard format, the ESRI PC ARCVIEW1 format for viewing the data, and the ESRI ARC/INFO export format. Extensive documentation is provided to describe the data, the sources, and data enhancements. The following data are provided. One group of coverages comes primarily from 1:2,000,000-scale National Atlas data and can be assembled for use as base maps. These various forms of topographic information. In addition, public land system data sets are provided from the 1:2,500,000-scale Geologic Map of the United States and 1:500,000-scale geologic maps of Nevada, Oregon, and Utah. Geochemical data from the National Uranium Resource Evaluation (NURE) program are provided for most of the Great Basin. Geophysical data are provided for most of the Great Basin, typically gridded data with a spacing of 1 km. The geophysical data sets include aeromagnetics, gravity, radiometric data, and several derivative products. The thematic data sets include geochronology, calderas, pluvial lakes, tectonic extension domains, distribution of pre-Cenozoic terranes, limonite anomalies, Landsat linear features, mineral sites, and Bureau of Land Management exploration and mining permits.

  14. The geologic history of Margaritifer basin, Mars (United States)

    Salvatore, M. R.; Kraft, M. D.; Edwards, Christopher; Christensen, P.R.


    In this study, we investigate the fluvial, sedimentary, and volcanic history of Margaritifer basin and the Uzboi-Ladon-Morava (ULM) outflow channel system. This network of valleys and basins spans more than 8000 km in length, linking the fluvially dissected southern highlands and Argyre Basin with the northern lowlands via Ares Vallis. Compositionally, thermophysically, and morphologically distinct geologic units are identified and are used to place critical relative stratigraphic constraints on the timing of geologic processes in Margaritifer basin. Our analyses show that fluvial activity was separated in time by significant episodes of geologic activity, including the widespread volcanic resurfacing of Margaritifer basin and the formation of chaos terrain. The most recent fluvial activity within Margaritifer basin appears to terminate at a region of chaos terrain, suggesting possible communication between surface and subsurface water reservoirs. We conclude with a discussion of the implications of these observations on our current knowledge of Martian hydrologic evolution in this important region.

  15. Drainage basin delineations for selected USGS streamflow-gaging stations in Virginia (Drainage_Basin) (United States)

    U.S. Geological Survey, Department of the Interior — The Drainage_Basin polygon feature class was created as a digital representation of drainage basins for more than 1,650 continuous-record streamflow-gaging stations,...

  16. Comparison of the bioavailability of elemental waste laden soils using in vivo and in vitro analytical methodology and refinement of exposure/dose models. 1998 annual progress report

    Energy Technology Data Exchange (ETDEWEB)

    Lioy, P.J.; Gallo, M.; Georgopoulos, P. [Univ. of Medicine and Dentistry of New Jersey, Piscataway, NJ (US). Exposure Measurement and Assessment Div.; Tate, R.; Buckley, B. [Rutgers, The State Univ. of New Jersey, New Brunswick, NJ (US)


    'The authors hypotheses are: (1) the more closely the synthetic, in vitro, extractant mimics the extraction properties of the human digestive bio-fluids, the more accurate will be the estimate of an internal dose; (2) performance can be evaluated by in vivo studies with a rat model and quantitative examination of a mass balance, calculation and dose estimates from model simulations for the in vitro and in vivo system; and (3) the concentration of the elements Pb, Cd, Cr and selected Radionuclides present in the bioavailable fraction obtained with a synthetic extraction system will be a better indicator of contaminant ingestion from a contaminated soil because it represents the portion of the mass which can yield exposure, uptake and then the internal dose to an individual. As of April 15, 1998, they have made significant progress in the development of a unified approach to the examination of bioavailability and bioaccessibility of elemental contamination of soils for the ingestion route of exposure. This includes the initial characterization of the soil, in vitro measurements of bioaccessibility, and in vivo measurements of bioavailability. They have identified the basic chemical and microbiological characteristics of waste laden soils. These have been used to prioritize the soils for potential mobility of the trace elements present in the soil. Subsequently they have employed a mass balance technique, which for the first time tracked the movement and distribution of elements through an in vitro or in vivo experimental protocol to define the bioaccessible and the bioavailable fractions of digested soil. The basic mass balance equation for the in vitro system is: MT = MSGJ + MIJ + MR. where MT is the total mass extractable by a specific method, MSGJ, is the mass extracted by the saliva and the gastric juices, MIJ is the mass extracted by the intestinal fluid, and MR is the unextractable portion of the initial mass. The above is based upon the use of a synthetic

  17. Hack's law of debris-flow basins

    Institute of Scientific and Technical Information of China (English)

    LI Yong; YUE Z.Q.; LEE C.F.; BEIGHLEY R.E.; CHEN Xiao-Qing; HU Kai-Heng; CUI Peng


    Hack's law was originally derived from basin statistics for varied spatial scales and regions.The exponent value of the law has been shown to vary between 0.47 and 0.70,causing uncertainty in its application.This paper focuses on the emergence of Hack's law from debris-flow basins in China.Over 5,000 debris-flow basins in different regions of China with drainage areas less than 100km2 are included in this study.Basins in the different regions are found to present similar distributions.Hack's law is derived fi'om maximum probability and conditional distributions,suggesting that the law should describe some critical state of basin evolution.Results suggest the exponent value is approximately 0.5.Further analysis indicates that Hack's law is related to other scaling laws underlying the evolution of a basin and that the exponent is not dependent on basin shape but rather on the evolutionary stage.A case study of a well known debris-flow basin further confirms Hack's law and its implications in basin evolution.

  18. Basin Management under the Global Climate Change (Take North-East Asia Heilongjiang -Amur Basin and Taihu Basin For Example) (United States)

    Liu, S.; Zhou, Z.; Zhong, G.; Zhang, X.


    The impact of global climate change on environment and society causes increasingly concern in different countries around the world. The main climate characteristic values, such as precipitation and temperature, have been changed, which leads to the variation of water resources, especially in large basins. Heilongjiang-Amur Basin and Taihu Basin are two large and important basins in China with large area and population. As global climate change and human activities have siganificant impacts on hydrology and water resources in two basins, the analysis of climate change are of great value. In this study, in Heilongjiang-Amur Basin, precipitation and temperature are investigated and their variation are predicted. And in Taihu Basin, precipitation including plum rain and typhoon, are studied and the variation trend of precipitation is predicted. Hence, the impacts of global climate change are assessed. From the result, it shows that the average temperature will continue to increase, and the precipitation will reduce first and then turn to increase in these two basins. It demonstrates that the water resources have been affected a lot by climate change as well as human activities. And these conclusions are provided as reference for policy makers and basin authorities in water resources management and natural hazards mitigation. Meanwhile, according to basins' particualr characters, the suggestions to future water resources management in two basins are given, and more scientific, comprehensive and sustained managements are required. Especially, in Heilongjiang-Amur River, which is a boundary river between China and Russia, it is very essential to enhance the cooperation between two countries.

  19. Relating petroleum system and play development to basin evolution: West African South Atlantic basins

    NARCIS (Netherlands)

    Beglinger, S.E.; Doust, H.; Cloetingh, S.A.P.L.


    Sedimentary basins can be classified according to their structural genesis and evolutionary history and the latter can be linked to petroleumsystem and playdevelopment. We propose an approach in which we use the established concepts in a new way: breaking basins down into their natural basin cycle d

  20. Evolution of the West Siberian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Vyssotski, A.V. [Chevron, 1500 Louisiana Street, Houston (United States); Vyssotski, V.N. [TNK-BP, 1 Arbat St, Moscow 119019 (Russian Federation); Nezhdanov, A.A. [OOO TyumenNIIgiprogas, 2 Vorovskogo Str., Tyumen 625019 (Russian Federation)


    The West Siberian Basin is one of the largest intra-cratonic basins of the world and an important hydrocarbon province of Russia. Perhaps the most important geologic event in Siberia was the emplacement of basalts around {approx} 250Ma (i.e. Permo-Triassic boundary) covering an area of about 5x10{sup 6} km{sup 2}. This volcanism may be responsible for a mass extinction that occurred around Permian-Triassic time. The pre-basaltic rifting event was limited to the north-northeastern sector of the basin. Initial basin wide subsidence took place in the Jurassic as a result of which the western part of Siberia became the West Siberian Basin bounded by uplifts to the east and to the west. One of the surprising aspects of the West Siberian Basin is the abundance of sub-vertical faults believed to be result of strike-slip movement. While intra-plate inversions and fault reactivation structures have been observed in many cratons, sub-vertical faults observed in the West Siberian Basin are unique because of their geometries and abundance. The differentiation between the effects of tectonics and eustasy in cratonic basins is simple-the global eustatic signal is basin-wide with regional and local tectonics playing an overprinting role. Thus, the Middle Jurassic-Turonian 1st, 2nd, and 3rd order cycles in the West Siberian Basin were primarily driven by eustasy. The Middle Jurassic-Turonian series can be subdivided into two second-order and 16 third-order transgressive-regressive cycles (within dataset extent). Fourth-order cycles appear to be controlled by delta shifting. Although extensively studied, a number of fundamental questions regarding the origin and evolution of the West Siberian Basin remain unresolved or poorly documented in the literature. [Author].

  1. Fractal basins in an ecological model

    Directory of Open Access Journals (Sweden)

    I. Djellit


    Full Text Available Complex dynamics is detected in an ecological model of host-parasitoid interaction. It illustrates fractalization of basins with self-similarity and chaotic attractors. This paper describes these dynamic behaviors, bifurcations, and chaos. Fractals basins are displayed by numerical simulations.

  2. Deep controls on intraplate basin inversion

    DEFF Research Database (Denmark)

    Nielsen, S.B.; Stephenson, Randell Alexander; Schiffer, Christian


    Basin inversion is an intermediate-scale manifestation of continental intraplate deformation, which produces earthquake activity in the interior of continents. The sedimentary basins of central Europe, inverted in the Late Cretaceous– Paleocene, represent a classic example of this phenomenon. It ...

  3. 33 CFR 401.48 - Turning basins. (United States)


    ... shall be turned about in any canal, except: (a) With permission from the traffic controller; and (b) At the locations set out in the table to this section. Table 1. South Shore Canal: (a) Turning Basin No. 1—Opposite Brossard. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut for vessels up...

  4. Neotectonic of subsiding basins : case of studies from Marañon and Beni basins, Peru and Bolivia


    Dumont, Jean-Francois


    Climatic conditions make the fluvial processes very sensitive in the extended flood plain of subandean basins, giving typical morphostructures. Because of high subsidence rate, these basins are case for the understanding of neotectonics in subsiding basins. Recent anciente fluvial traces are used in combination with sub surface structures, neotectonic and seismotectonic data to study the neotectonic evolution of the Peruvian and Bolivian active foreland basins. These basins, the Marañon Basin...

  5. Basins in ARC-continental collisions (United States)

    Draut, Amy E.; Clift, Peter D.; Busby, Cathy; Azor, Antonio


    Arc-continent collisions occur commonly in the plate-tectonic cycle and result in rapidly formed and rapidly collapsing orogens, often spanning just 5-15 My. Growth of continental masses through arc-continent collision is widely thought to be a major process governing the structural and geochemical evolution of the continental crust over geologic time. Collisions of intra-oceanic arcs with passive continental margins (a situation in which the arc, on the upper plate, faces the continent) involve a substantially different geometry than collisions of intra-oceanic arcs with active continental margins (a situation requiring more than one convergence zone and in which the arc, on the lower plate, backs into the continent), with variable preservation potential for basins in each case. Substantial differences also occur between trench and forearc evolution in tectonically erosive versus tectonically accreting margins, both before and after collision. We examine the evolution of trenches, trench-slope basins, forearc basins, intra-arc basins, and backarc basins during arc-continent collision. The preservation potential of trench-slope basins is low; in collision they are rapidly uplifted and eroded, and at erosive margins they are progressively destroyed by subduction erosion. Post-collisional preservation of trench sediment and trench-slope basins is biased toward margins that were tectonically accreting for a substantial length of time before collision. Forearc basins in erosive margins are usually floored by strong lithosphere and may survive collision with a passive margin, sometimes continuing sedimentation throughout collision and orogeny. The low flexural rigidity of intra-arc basins makes them deep and, if preserved, potentially long records of arc and collisional tectonism. Backarc basins, in contrast, are typically subducted and their sediment either lost or preserved only as fragments in melange sequences. A substantial proportion of the sediment derived from


    Institute of Scientific and Technical Information of China (English)

    张炎圣; 陆新征; 叶列平; 何水涛


    近年,超高车辆撞击桥梁上部结构问题成为城市交通安全的重要威胁.为减少超高车辆撞击桥梁上部结构造成的损失,关键是准确计算撞击荷载.该文首先基于精细有限元,对超高车辆-桥梁上部结构碰撞过程进行了模拟,对影响撞击的主要参数进行了分析.进而通过忽略次要影响因素,对车辆、桥梁受力行为进行合理简化,建立了超高车辆-桥梁上部结构碰撞的简化计算模型.简化模型与精细有限元模型的撞击力时程结果吻合较好,可为工程设计提供参考.%Recently the collisions between over-high trucks and bridge superstructures have become a serious threaten to the safety of city traffic. In order to reduce the loss due to collision accidents, it's critical to precisely calculate the collision loads. This work firstly simulates the collision process between over-high trucks and bridge superstructures based on high precision finite element model, with primary influencing factors that control the collision loads being discussed. Then by ignoring the minor influencing factors, a simplified model for the collision between over-high trucks and bridge superstructures has been developed. The time-history results of simplified model agree well with those of the high precision finite element model, thus the proposed simplified model can be used in practical application.

  7. Determination of the Relationship between Hydrologic Processes and Basin Morphometry - The Lamos Basin (Mersin, Turkey) (United States)

    Yıldırım, Ümit; Güler, Cüneyt


    This study has been carried out to determine the relationship between hydrologic processes and basin morphometry in the Lamos Basin, which is located at the northern part of the Mersin (SE Turkey). The morphometric parameters of the basin was derived from the 1:25K scale topographic map sheets that were digitized using ArcGIS 9.3.1 geographic information system (GIS) software. Morphometric parameters considered in this study include basin area, basin length, basin perimeter length, stream order, stream number, stream length, mean stream length, basin relief, drainage density, stream frequency, drainage texture, bifurcation ratio, form factor, elongation ratio, overland flow length, relief ratio, and hypsometric integral. The results have shown that there are 1252 individual stream reaches with a total length of 1414.1 km in the Lamos basin, which covers an area of 1358 km2 and has a length of 103 km in the N-S direction. Furthermore, the basin has a medium drainage density of 1.04 1/km with a stream frequency and drainage texture values of 0.92 and 4.33, respectively. The basin can be classified as elongated because of the low values of elongation ratio (0.48) and form factor (0.12). The hypsometric integral of the basin (0.58) indicates that it is in the youth period and thus reasonably sensitive to erosion. The values of drainage texture, drainage density, and stream frequency indicate that the Lamos basin is moderately well drained, therefore overland flow in the basin is not expected to be so quick. Thus, in case of occurrence of sudden peak flows, sensitivity to the land sliding and erosion may increase further. As a result, it is suggested that human activities in the basin should be limited in areas in fairly close proximity to the present day stream network to prevent or reduce the risk to life and property.

  8. On the Objectivity of Value-laden in the Perspective of Feminist Epistemology%女性主义知识论视野下的价值负载的客观性

    Institute of Scientific and Technical Information of China (English)



    Feminist epistemology believes that the objectivity of traditional epistemology is value‐neu‐tral ,which is impossible and worthless to achieve .Both the community objectivity by Helen E .Longino and the dynamic objectivity by Evelyn Fox Keller have advocated the value‐laden objectivity w hich causes such criticisms from other opponents as followings :Does the value‐laden objectivity claim political priority ?Is it a paradox?Will it inevitably lead to relativism ?These criticisms can be refuted from the perspective of feminist epistemology .%女性主义知识论认为,传统知识论中的客观性是价值中立的,这种客观性既不可能实现,也不值得实现。无论是朗基诺的共同体客观性,还是凯勒的动态的客观性,都主张价值负载。对于价值负载的客观性,反对者作出了许多批判。这些批判主要有:价值负载的客观性主张政治的优先性吗?价值负载的客观性自相矛盾吗?价值负载的客观性必然导致相对主义吗?对这些批判,可从女性主义知识论的角度予以反驳。

  9. Delaware basin/Central basin platform margin: The development of a subthrust deep-gas province in the Permian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Purves, W.J. (Mobil Oil Corp., Midland, TX (USA)); Ting, S.C. (Mobil, Farmers Branch, TX (USA))


    A deep-gas-prone province was identified along the Delaware basin/Central Basin platform margin, a margin conventionally interpreted to be bounded by high-angle normal or high-angle reverse structures. Redefinition of the tectonic style between the Delaware basin and the adjacent platform resulted in the identification of this Delaware basin/Central Basin platform subthrust province and a giant prospect within it. Definition of a giant-sized gas prospect in northern Pecos County, Texas, revealed that portions of this margin may be characterized by shingled, low-angle, eastward-dipping, basement involved thrust faults. Interpretations suggest that hidden, subthrust footwall structures may trend discontinuously for greater than 100 mi along this structural margin. Subthrust footwall structures formed as basinal buttress points for the Central Basin platform to climb over the Delaware basin. In this area, structural relief of over 19,000 ft over a 10-mi width is believed due to stacking of low-angle thrust sheets. Seismic resolution of this subthrust margin has been complexed by allochtonous hanging-wall gravity-glide blocks and folds and by velocity changes in overlying syn- and posttectonic sediments associated with basin-to-shelf lithofacies changes. Statistical studies indicate that this deep-gas province has a play potential of greater than 10 tcf of gas, with individual prospect sizes exceeding 1 tcfg. The prospects defined along this trend are deep (approximately 20,000 ft) subthrust structural traps that are indigenously sourced and reservoired by dual-matrix porosity. Vitrinite supported maturation modeling suggests that these subthrust structures formed prior to catagenic conversion of the oldest source rocks to oil and later to gas. Tectonically fractured Ordovician Ellenburger and Devonian sediments are considered the principal reservoirs. Shales overlying reservoir intervals form vertical seals.

  10. The Voisey's Bay Ni-Cu-Co Sulfide Deposit,Labrador,Canada:Emplacement of Silicate and Sulfide-Laden Magmas into Spaces Created within a Structural Corridor%The Voisey's Bay Ni-Cu-Co Sulfide Deposit,Labrador, Canada: Emplacement of Silicate and Sulfide-Laden Magmas into Spaces Created within a Structural Corridor

    Institute of Scientific and Technical Information of China (English)

    Peter C.Lightfoot; Dawn Evans-Lamswood; Robert Wheeler


    ,development of barren olivine gabbro,and by a change from typically massive sulfides and breccias sulfides into more typical variable-textured troctolites with heavy to weak disseminated sulfide.Sulfides hosted in the feeder dyke tend to have low metal tenors ([Ni] 100=2.5%-3.5 %) ; sulfides in Eastern Deeps massive and breccia ores have intermediate Ni tenors ([Ni] 100 =3.5%-4%) and disseminated sulfides in overlying rocks have high Ni tenors ([Ni] 100=4%-8%).Conduit-hosted mineralization and mineral zones in the paragneiss adjacent to the Reid Brook Deposit tendto have lower Ni tenor than the Ovoid and Eastern Deeps Deposits.The tenor of mineral hosted in thecountry rock gneisses tends to be the same as that developed in the conduit; the injection of the sulfide in-to the country rocks likely occurred before formation of monosulfide solid solution.The Ovoid Deposit ischaracterized by coarse-grained loop-textured ores consisting of 10cm-2m sized pyrrhotite crystals sepera-ted by chalcopyrite and pentlandite.A small lens of massive cubanite surrounded by more magnetite-richsulfide assemblages represents what appears to be the product of in-situ sulfide fractionation.Detailed exploration in the area between the Reid Brook Zone and the Eastern Deeps has shown thatthese intrusions and ore deposits are connected by a branched dyke and chamber system in a major west-east fault zone.The Eastern Deeps chamber may be controlled by graben-like fault structures,and themarginal structures appear to have controlled dykes which connect the chambers at different levels in thecrust.The geological relationships in the intrusion are consistent with emplacement of the silicate and sul-fide laden magma from a deeper sub-chamber (possibly a deep eastward extension of the Western DeepsIntrusion where S-saturation was initially achieved).The silicate and sulfide magmas were likely emplacedthrough this conduit into the Eastern Deeps intrusion as a number of different fragment laden pulses

  11. Submarine Landslides in Arctic Sedimentation: Canada Basin (United States)

    Mosher, David C.; Shimeld, John; Hutchinson, Deborah R.; Lebedova-Ivanova, N; Chapman, C.


    Canada Basin of the Arctic Ocean is the least studied ocean basin in the World. Marine seismic field programs were conducted over the past 6 years using Canadian and American icebreakers. These expeditions acquired more than 14,000 line-km of multibeam bathymetric and multi-channel seismic reflection data over abyssal plain, continental rise and slope regions of Canada Basin; areas where little or no seismic reflection data existed previously. Canada Basin is a turbidite-filled basin with flat-lying reflections correlateable over 100s of km. For the upper half of the sedimentary succession, evidence of sedimentary processes other than turbidity current deposition is rare. The Canadian Archipelago and Beaufort Sea margins host stacked mass transport deposits from which many of these turbidites appear to derive. The stratigraphic succession of the MacKenzie River fan is dominated by mass transport deposits; one such complex is in excess of 132,000 km2 in area and underlies much of the southern abyssal plain. The modern seafloor is also scarred with escarpments and mass failure deposits; evidence that submarine landsliding is an ongoing process. In its latest phase of development, Canada Basin is geomorphologically confined with stable oceanographic structure, resulting in restricted depositional/reworking processes. The sedimentary record, therefore, underscores the significance of mass-transport processes in providing sediments to oceanic abyssal plains as few other basins are able to do.

  12. How integrated is river basin management? (United States)

    Downs, Peter W.; Gregory, Kenneth J.; Brookes, Andrew


    Land and water management is increasingly focused upon the drainage basin. Thirty-six terms recently used for schemes of “integrated basin management” include reference to the subject or area and to the aims of integrated river basin management, often without allusion to the multiobjective nature. Diversity in usage of terms has occurred because of the involvement of different disciplines, of the increasing coherence of the drainage basin approach, and the problems posed in particular parts of the world. The components included in 21 different approaches are analyzed, and, in addition to showing that components related broadly to water supply, river channel, land, and leisure aspects, it is concluded that there are essentially five interrelated facets of integrated basin management that involved water, channel, land, ecology, and human activity. Two aspects not fully included in many previous schemes concern river channel changes and the dynamic integrity of the fluvial system. To clarify the terminology used, it is suggested that the term comprehensive river basin management should be used where a wide range of components is involved, whereas integrated basin management can signify the interactions of components and the dominance of certain components in the particular area. Holistic river basin management is advocated as a term representing an approach that is both fully comprehensive and integrated but also embraces the energetics of the river system and consideration of changes of river channels and of human impacts throughout the river system. The paradigm of working with the river can be extended to one of working with the river in the holistic basin context.

  13. Tectono-stratigraphic evolution of an inverted extensional basin: the Cameros Basin (north of Spain) (United States)

    Omodeo Salè, Silvia; Guimerà, Joan; Mas, Ramón; Arribas, José


    The Cameros Basin is a part of the Mesozoic Iberian Rift. It is an extensional basin formed during the late Jurassic and early Cretaceous, in the Mesozoic Iberian Rift context, and it was inverted in the Cenozoic as a result of the Alpine contraction. This work aims to reconstruct the tectono-stratigraphic evolution of the basin during the Mesozoic, using new and revised field, geophysical and subsurface data. The construction of a basin-wide balanced section with partial restorations herein offers new insights into the geometry of the syn-rift deposits. Field data, seismic lines and oil well data were used to identify the main structures of the basin and the basin-forming mechanisms. Mapping and cross-sectional data indicate the marked thickness variation of the depositional sequences across the basin, suggesting that the extension of the depositional area varied during the syn-rift stage and that the depocentres migrated towards the north. From field observation and seismic line interpretation, an onlap of the depositional sequences to the north, over the marine Jurassic substratum, can be deduced. In the last few decades, the structure and geometry of the basin have been strongly debated. The structure and geometry of the basin infill reconstructed herein strongly support the interpretation of the Cameros Basin as an extensional-ramp synclinal basin formed on a blind south-dipping extensional ramp. The gradual hanging-wall displacement to the south shifted the depocentres to the north over time, thus increasing the basin in size northwards, with onlap geometry on the pre-rift substratum. The basin was inverted by means of a main thrust located in a detachment located in the Upper Triassic beds (Keuper), which branched in depth with the Mesozoic extensional fault flat. The reconstruction of the tectono-stratigraphic evolution of the Cameros Basin proposed herein represents a synthesis and an integration of previous studies of the structure and geometry of the

  14. Western Gas Sands Project. Quarterly Basin Activities Report

    Energy Technology Data Exchange (ETDEWEB)

    Atkinson, C H


    This report is a summation of 3 months' drilling and testing activities in the four primary WGSP study areas: Greater Green River Basin, Northern Great Plains Province, Piceance Basin, and Uinta Basin. The monitoring of basin activities is part of resource assessment. (DLC)

  15. Western Gas Sands Project Quarterly Basin Activities Report

    Energy Technology Data Exchange (ETDEWEB)

    Atkinson, C H


    This quarterly basin activities report is a summation of three months drilling and testing activities in the Greater Green River Basin, Northern Great Plains Province, Piceance Basin, and Uinta Basin. Detailed information is given for each study area for the first quarter of 1979.

  16. Waste storage potential of Triassic basins in southeast United States

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, C.E.


    Triassic basins, elongated deep basins filled with sediments, extend from Nova Scotia to Florida. The geology of the basins is discussed for each state. Their potential for liquid waste storage is assessed. Seismic risk is among the factors evaluated. It is recommended that the shallow Triassic Florence basin in northeast South Carolina be studied. 10 fig. (DLC)

  17. K Basins isolation barriers summary report

    Energy Technology Data Exchange (ETDEWEB)

    Strickland, G.C., Westinghouse Hanford


    The 105-K East and 105-K West fuel storage basins (105-K Basins) were designed and constructed in the early 1950`s for interim storage of irradiated fuel following its discharge from the reactors. The 105-K- East and 105-K West reactor buildings were constructed first, and the associated storage basins were added about a year later. The construction joint between each reactor building structure and the basin structure included a flexible membrane waterstop to prevent leakage. Water in the storage basins provided both radiation shielding and cooling to remove decay heat from stored fuel until its transfer to the Plutonium Uranium Extraction (PUREX) Facility for chemical processing. The 105-K West Reactor was permanently shut down in February 1970; the 105-K East Reactor was permanently shut down in February 1971. Except for a few loose pieces, fuel stored in the basins at that time was shipped to the PUREX Facility for processing. The basins were then left idle but were kept filled with water. The PUREX Facility was shut down and placed on wet standby in 1972 while N Reactor continued to operate. When the N Reactor fuel storage basin began to approach storage capacity, the decision was made to modify the fuel storage basins at 105-K East and 105-K West to provide additional storage capacity. Both basins were subsequently modified (105-K East in 1975 and 105-K West in 1981) to provide for the interim handling and storage of irradiated N Reactor fuel. The PUREX Facility was restarted in November 1983 to provide 1698 additional weapons-grade plutonium for the United States defense mission. The facility was shut down and deactivated in December 1992 when the U.S. Department of Energy (DOE) determined that the plant was no longer needed to support weapons-grade plutonium production. When the PUREX Facility was shut down, approximately 2.1 x 1 06 kg (2,100 metric tons) of irradiated fuel aged 7 to 23 years was left in storage in the 105-K Basins pending a decision on

  18. Gravity Analysis of the Jeffera Basin, Tunisia (United States)

    Mickus, K.; Gabtni, H.; Jallouli, C.


    Southern Tunisia consists of two main tectonic provinces: 1) the Saharan Platform and 2) the folded Atlasic domain, separated by the North Saharan Flexure. The Saharan Platform, which contains the Ghadames Basin and the Telemzane Arch, consists of gently dipping Paleozoic strata overlain by Triassic to Cretaceous sediments. The Atlasic domain consists of a thicker sequence of mainly Mesozoic and younger rock with less complete sequences of Paleozoic strata. Within the Atlasic domain are the still actively subsiding Chotts and Jeffera basins. The Jeffera basin, which occurs to the east of the Telemzane Arch contains at least eight kilometers of Paleozoic and younger sediment that were formed during numerous subsidence episodes since Carboniferous time. The Jeffera basin is dominated by tilted fault blocks that were formed during numerous tectonic episodes. Several unpublished seismic reflection profiles and well data exist for the Jeffera basin, however a deep structural analysis of the basin has not been published. We examined the existing gravity data in conjunction with available well and geologic data to determine structural features within the basin. The Bouguer gravity anomaly map shows that the Jeffera basin is dominated by a narrow northwest-trending gravity minimum. However, a more detailed analysis consisting of wavelength filtering and edge enhancements indicate that the structure of the basin is more complicated than indicated by the Bouguer gravity anomaly map. A residual gravity anomaly map indicates that the Jeffera basin consists of at least three and maybe four subbasins. Additionally, the Jeffera Fault marks the boundary between northwest-trending gravity anomalies to its northeast and east-trending anomalies over the Saharan Platform. The above observation is amplified by the construction of the enhanced horizontal derivatives (EHG) of both the complete Bouguer gravity and the residual gravity anomaly maps. The EHG maps highlight the lateral

  19. Inner Harbor Navigation Canal Basin Velocity Analysis (United States)


    ER D C/ CH L TR -1 4- 12 Inner Harbor Navigation Canal Basin Velocity Analysis Co as ta l a nd H yd ra ul ic s La bo ra to ry...library at ERDC/CHL TR-14-12 October 2014 Inner Harbor Navigation Canal Basin Velocity Analysis...system of levees, gates, and drainage structures in the Inner Harbor Navigation Canal (IHNC) basin and the greater New Orleans, Louisiana, area. Two

  20. Tarim Basin: China's Potential Oil Giant

    Institute of Scientific and Technical Information of China (English)

    Qiu Baolin


    @@ Tarim Basin has an area of 560,000 square kilometers.Taklamakan Desert, the world's second largest shifting desert, is located in the hinterland of the basin. The desert is equal to Germany in area. The desert is called "Desert of No Return" for its harsh and adverse environments. A 522-kilometer highway crossing the desert from north to south was opened to the traffic in 1995 because an oilfield with the reserves of more than 100 million tons was discovered in the central part of the basin. The local traffic and ecological conditions have been much improved in the recent years.

  1. Rifting Thick Lithosphere - Canning Basin, Western Australia (United States)

    Czarnota, Karol; White, Nicky


    The subsidence histories and architecture of most, but not all, rift basins are elegantly explained by extension of ~120 km thick lithosphere followed by thermal re-thickening of the lithospheric mantle to its pre-rift thickness. Although this well-established model underpins most basin analysis, it is unclear whether the model explains the subsidence of rift basins developed over substantially thick lithosphere (as imaged by seismic tomography beneath substantial portions of the continents). The Canning Basin of Western Australia is an example where a rift basin putatively overlies lithosphere ≥180 km thick, imaged using shear wave tomography. Subsidence modelling in this study shows that the entire subsidence history of the Canning Basin is adequately explained by mild Ordovician extension (β≈1.2) of ~120 km thick lithosphere followed by post-rift thermal subsidence. This is consistent with the established model, described above, albeit with perturbations due to transient dynamic topography support which are expressed as basin-wide unconformities. In contrast the Canning Basin reveals an almost continuous period of normal faulting between the Ordovician and Carboniferous (βCanning Basin to rifting of thick lithosphere beneath the eastern part, verified by the presence of ~20 Ma diamond-bearing lamproites intruded into the basin depocentre. In order to account for the observed subsidence, at standard crustal densities, the lithospheric mantle is required to be depleted in density by 50-70 kg m-3, which is in line with estimates derived from modelling rare-earth element concentrations of the ~20 Ma lamproites and global isostatic considerations. Together, these results suggest that thick lithosphere thinned to > 120 km is thermally stable and is not accompanied by post-rift thermal subsidence driven by thermal re-thickening of the lithospheric mantle. Our results show that variations in lithospheric thickness place a fundamental control on basin architecture

  2. Structural Architecture and Evolution of Kumkuli Basin, North Tibet

    Institute of Scientific and Technical Information of China (English)

    He Bizhu; Xu Zhiqin; Jiao Cunli; Cui Junwen; Wang Shenglang; Wang Gonghuai; Li Zhaoyang; Qiu Zhuli


    Utilizing the new data of gravity, magnetic, and magnetotelluric survey, we analyzed the characteristics of the three geophysical attribute (gravity, magnetic, and resistivity) interfaces and the deep architecture and structure of Kumkuli basin. The research results can provide basic data for early basin structural study. From coupled basin and mountain system, analysis of the structure, and evolution of Knmknli basin, we found that there was zoning from north to south and from west to east. Kumkuli basin has three structural architecture layers including metamorphic crystallization basement, fold basement and sedimentary cover. Knmkuli basin can be divided into three structural units, two depressions, and one uplift. Structural evolution of the Kumkuli basin can be divided into five evolution stages, including Kumkuli microcontinent formed in Sinian-Ordovician, suture around Kumkuli basin formed in Eopaleozoic, retroarc foreland basin formed in Neopaleozoic, rejuvenated foreland hasin developed in Mesozoic, and strike slip and compression basin developed in Cenozoic.


    Energy Technology Data Exchange (ETDEWEB)

    David J. Taylor


    Some 140 miles of multichannel seismic reflection data, acquired commercially in the 1970's, were reprocessed by the U.S. Geological Survey in late 2000 and early 2001 to interpret the subsurface geology of the Crazy Mountains Basin, an asymmetric Laramide foreland basin located in south-central Montana. The seismic data indicate that the northwestern basin margin is controlled by a thrust fault that places basement rocks over a thick (22,000 feet) sequence of Paleozoic and Mesozoic sedimentary rocks to the south. From the deep basin trough, Paleozoic through Tertiary rocks slope gently upward to the south and southeast. The northern boundary of the basin, which is not imaged well by the seismic data, appears to be folded over a basement ridge rather than being truncated against a fault plane. Seismic data along the basin margin to the south indicate that several fault controlled basement highs may have been created by thin-skinned tectonics where a series of shallow thrust faults cut Precambrian, Paleozoic, and early Mesozoic rocks, whereas, in contrast, Cretaceous and Tertiary strata are folded. The data are further interpreted to indicate that this fault-bounded asymmetric basin contains several structures that possibly could trap hydrocarbons, provided source rocks, reservoirs, and seals are present. In addition, faults in the deep basin trough may have created enough fracturing to enhance porosity, thus developing ''sweet spots'' for hydrocarbons in basin-centered continuous gas accumulations.

  4. K-Basins S/RIDS

    Energy Technology Data Exchange (ETDEWEB)

    Watson, D.J.


    The Standards/Requirements Identification Document (S/RID) is a list of the Environmental, Safety, and Health (ES{ampersand}H) and Safeguards and Security (SAS) standards/requirements applicable to the K Basins facility.

  5. K-Basins S/RIDS

    Energy Technology Data Exchange (ETDEWEB)

    Watson, D.J.


    The Standards/Requirements Identification Document(S/RID) is a list of the Environmental, Safety, and Health (ES&H) and Safeguards and Security (SAS) standards/requirements applicable to the K Basins facility

  6. USGS Streamgage NHDPlus Version 1 Basins 2011 (United States)

    U.S. Geological Survey, Department of the Interior — This dataset represents 19,031 basin boundaries and their streamgage locations for the U.S. Geological Survey's (USGS) active and historical streamgages from the...

  7. Ferris coalfield boundary, Hanna Basin, Wyoming (ferbndg) (United States)

    U.S. Geological Survey, Department of the Interior — This ArcView shapefile contains a representation of the boundary of the Ferris coalfield in the Hanna Basin, Wyoming. This theme was created specifically for the...

  8. Cretaceous Onlap, Gulf of Mexico Basin [cretonlapg (United States)

    U.S. Geological Survey, Department of the Interior — The maximum extent of Cretaceous onlap is generalized from Plate 3, Structure at the base and subcrop below Mesozoic marine section, Gulf of Mexico Basin (compiled...

  9. Oil production in the Orinoco basin

    Energy Technology Data Exchange (ETDEWEB)

    Borregales, C.J.


    With an extension of 42,000 sq km, the Orinoco basin is one of the largest petroliferous zones in the world which contains high viscosity and low API gravity crude. Results from production tests performed in the central and southern parts of the basin indicate that its productive potential is similar to that in Morichal, Pilon and Jobo fields, and reveals that the heaviest oil existing in the Orinoco basin could be economically exploited by conventional methods of primary oil recovery. It is estimated that the oil recovery could be 5% of the total oil-in-place by using primary recovery methods, 8% by using alternate steam injection, and 20% by secondary recovery methods (continuous steam injection). However, if the compaction phenomenon takes place, an estimate of 5% to 15% additional oil recovery could be possible. Geology, fluid properties, results from production tests, and recovery methods in the Orinoco basin are presented.

  10. Gulf Coast Basins and Uplifts [gcstructsg (United States)

    U.S. Geological Survey, Department of the Interior — These data provide generalized outlines of major basins and uplifts in the Gulf Coast region modified after Plate 2, Principal structural features, Gulf of Mexico...

  11. River Basin Standards Interoperability Pilot (United States)

    Pesquer, Lluís; Masó, Joan; Stasch, Christoph


    There is a lot of water information and tools in Europe to be applied in the river basin management but fragmentation and a lack of coordination between countries still exists. The European Commission and the member states have financed several research and innovation projects in support of the Water Framework Directive. Only a few of them are using the recently emerging hydrological standards, such as the OGC WaterML 2.0. WaterInnEU is a Horizon 2020 project focused on creating a marketplace to enhance the exploitation of EU funded ICT models, tools, protocols and policy briefs related to water and to establish suitable conditions for new market opportunities based on these offerings. One of WaterInnEU's main goals is to assess the level of standardization and interoperability of these outcomes as a mechanism to integrate ICT-based tools, incorporate open data platforms and generate a palette of interchangeable components that are able to use the water data emerging from the recently proposed open data sharing processes and data models stimulated by initiatives such as the INSPIRE directive. As part of the standardization and interoperability activities in the project, the authors are designing an experiment (RIBASE, the present work) to demonstrate how current ICT-based tools and water data can work in combination with geospatial web services in the Scheldt river basin. The main structure of this experiment, that is the core of the present work, is composed by the following steps: - Extraction of information from river gauges data in OGC WaterML 2.0 format using SOS services (preferably compliant to the OGC SOS 2.0 Hydrology Profile Best Practice). - Model floods using a WPS 2.0, WaterML 2.0 data and weather forecast models as input. - Evaluation of the applicability of Sensor Notification Services in water emergencies. - Open distribution of the input and output data as OGC web services WaterML, / WCS / WFS and with visualization utilities: WMS. The architecture


    NARCIS (Netherlands)



    Structure factors obtained from neutron diffraction measurements on liquid K-Tl and Cs-Tl alloys exhibit large prepeaks at approximately 0.77 angstrom-1 and 0.70 angstrom-1, respectively. It is concluded that the liquid contains large units of thallium atoms, possibly bearing some resemblance to tho

  13. The route to protein aggregate superstructures

    DEFF Research Database (Denmark)

    Vetri, Valeria; Foderà, Vito


    Depending on external conditions, native proteins may change their structure and undergo different association routes leading to a large scale polymorphism of the aggregates. This feature has been widely observed but is not fully understood yet. This review focuses on morphologies, physico-chemical...

  14. Fractal Basins in the Lorenz Model

    Institute of Scientific and Technical Information of China (English)

    I.Djellit; J.C.Sprott; M. R. Ferchichi


    @@ The Lorenz mapping is a discretization of a pair of differential equations.It illustrates the pertinence of compu- tational chaos.We describe complex dynamics, bifurcations, and chaos in the map.Fractal basins are displayed by numerical simulation.%The Lorenz mapping is a discretization of a pair of differential equations. It illustrates the pertinence of computational chaos. We describe complex dynamics, bifurcations, and chaos in the map. Fractal basins are displayed by numerical simulation.

  15. Microbiology of spent nuclear fuel storage basins. (United States)

    Santo Domingo, J W; Berry, C J; Summer, M; Fliermans, C B


    Microbiological studies of spent nuclear fuel storage basins at Savannah River Site (SRS) were performed as a preliminary step to elucidate the potential for microbial-influenced corrosion (MIC) in these facilities. Total direct counts and culturable counts performed during a 2-year period indicated microbial densities of 10(4) to 10(7) cells/ml in water samples and on submerged metal coupons collected from these basins. Bacterial communities present in the basin transformed between 15% and 89% of the compounds present in Biologtrade mark plates. Additionally, the presence of several biocorrosion-relevant microbial groups (i.e., sulfate-reducing bacteria and acid-producing bacteria) was detected with commercially available test kits. Scanning electron microscopy and X-ray spectra analysis of osmium tetroxide-stained coupons demonstrated the development of microbial biofilm communities on some metal coupons submerged for 3 weeks in storage basins. After 12 months, coupons were fully covered by biofilms, with some deterioration of the coupon surface evident at the microscopical level. These results suggest that, despite the oligotrophic and radiological environment of the SRS storage basins and the active water deionization treatments commonly applied to prevent electrochemical corrosion in these facilities, these conditions do not prevent microbial colonization and survival. Such microbial densities and wide diversity of carbon source utilization reflect the ability of the microbial populations to adapt to these environments. The presumptive presence of sulfate-reducing bacteria and acid-producing bacteria and the development of biofilms on submerged coupons indicated that an environment for MIC of metal components in the storage basins may occur. However, to date, there has been no indication or evidence of MIC in the basins. Basin chemistry control and corrosion surveillance programs instituted several years ago have substantially abated all corrosion mechanisms.

  16. Water scarcity in the Jordan River basin. (United States)

    Civic, M A


    This article reports the problem on water scarcity in the Jordan River basin. In the Jordan River basin, freshwater scarcity results from multiple factors and most severely affects Israel, Jordan, the West Bank, and the Gaza Strip. One of these multiple factors is the duration of rainfall in the region that only occurs in a small area of highlands in the northwest section. The varying method of water use parallels that of Israel that utilizes an estimated 2000 million cu. m. The national patterns of water usage and politically charged territorial assertions compound the competition over freshwater resources in the region. The combination of political strife, resource overuse, and contaminated sources means that freshwater scarcity in the Jordan River basin will reach a critical level in the near future. History revealed that the misallocation/mismanagement of freshwater from the Jordan River basin was the result of centuries of distinct local cultural and religious practices combined with historical influences. Each state occupying near the river basin form their respective national water development schemes. It was not until the mid-1990s that a shared-use approach was considered. Therefore, the critical nature of water resource, the ever-dwindling supply of freshwater in the Jordan River basin, and the irrevocability of inappropriate policy measures requires unified, definitive, and ecologically sound changes to the existing policies and practices to insure an adequate water supply for all people in the region.

  17. Geothermal resources of California sedimentary basins (United States)

    Williams, C.F.; Grubb, F.V.; Galanis, S.P.


    The 2004 Department of Energy (DOE) Strategic Plan for geothermal energy calls for expanding the geothermal resource base of the United States to 40,000 MW of electric power generating potential. This will require advances in technologies for exploiting unconventional geothermal resources, including Enhanced Geothermal Systems (EGS) and geopressured geothermal. An investigation of thermal conditions in California sedimentary basins through new temperature and heat flow measurements reveals significant geothermal potential in some areas. In many of the basins, the combined cooling effects of recent tectonic and sedimentary processes result in relatively low (geothermal gradients. For example, temperatures in the upper 3 km of San Joaquin, Sacramento and Ventura basins are typically less than 125??C and do not reach 200??c by 5 km. By contrast, in the Cuyama, Santa Maria and western Los Angeles basins, heat flow exceeds 80 mW/m2 and temperatures near or above 200??C occur at 4 to 5 km depth, which represents thermal conditions equivalent to or hotter than those encountered at the Soultz EGS geothermal site in Europe. Although the extractable geothermal energy contained in these basins is not large relative to the major California producing geothermal fields at The Geysers or Salton Sea, the collocation in the Los Angeles basin of a substantial petroleum extraction infrastructure and a major metropolitan area may make it attractive for eventual geothermal development as EGS technology matures.

  18. Short description of the Peruvian coal basins

    Energy Technology Data Exchange (ETDEWEB)

    Carrascal-Miranda, Eitel R. [UNI, Lima (Peru); Suarez-Ruiz, Isabel [Instituto Nacional del Carbon (CSIC), Ap. Co., 73, 33080 Oviedo (Spain)


    This work synthesizes the main general characteristics of the Peruvian Coal Basins in relation to age, coal facies and coal rank. Peruvian coals are located in a series of coal basins from the Paleozoic to the Cenozoic age. Paleozoic coal seams are mainly of Mississippian age (Carboniferous). They are of continental origin and their reduced thickness and ash content are their main characteristics. Mesozoic coal seams (Upper Jurassic-Lower Cretaceous) are located in the so-called Peruvian Western Basin and in the depressions close to the 'Maranon Geoanticline'. They were originated in deltaic facies under the influence of brackish and fresh waters. Some of these coal basins (those distributed in the central and northern parts of Peru) are relatively well known because they are of economic importance. Finally, Cenozoic coal seams (Tertiary) are found in both paralic and limnic basins and their reserves are limited. All the Peruvian coals are of humic character and are vitrinite-rich. Their rank is highly variable and normally related with the different orogenic events which strongly affected this region. Thus, Paleozoic and Mesozoic coals are of bituminous to anthracite/meta-anthracite coal rank while peats, lignite and subbituminous coals are found in Cenozoic basins.

  19. On Restoring Sedimentary Basins for Post-Depositional Deformation - Paleozoic Basins of the Central Andes (United States)

    Bahlburg, H.


    The reconstruction and interpretation of sedimentary basins incorporated into folded and thrusted mountain belts is strongly limited by the style and intensity of shortening. This problem is exacerbated if deformation is polyphasic as is the case for the Paleozoic basins in the central Andes. Some of these have been deformed by folding and thrusting during at least 3 events in the Late Ordovician, the Late Paleozoic and Cenozoic. A realistic reconstruction of the original basin dimensions and geometries from outcrops and maps appears to be almost impossible. We present results of a stepwise reconstruction of the Paleozoic basins of the central Andes by restoring basin areas and fills accounting for crustal shortening. The structurally most prominent feature of the central Andes is the Bolivian Orocline which accomodated shortening in the last 45 Ma on the order of between 300 and 500 km. In a first step basins were restored by accounting for Cenozoic rotation and shortening by deconvolving the basins using an enhanced version of the oroclinal bending model of Ariagada et al. (2008). Results were then restored stepwise for older deformation. Constraints on these subsequent steps are significantly poorer as values of shortening can be derived only from folds and thusts apparent in outcrops. The amount of shortening accomodated on unexposed and therefore unknown thrusts can not be quantified and is a significant source of error very likely leading to an underestimation of the amount of shortening. Accepting these limitations, basin restoration results in an increase in basin area by ≥100%. The volumes of stratigraphically controlled basin fills can now be redistributed over the wider, restored area, translating into smaller rates of accumulation and hence required subsidence. The restored rates conform to those of equivalent modern basin settings and permit a more realistic and actualistic analysis of subsidence drivers and the respective tectonic framework.

  20. 载细胞水凝胶体系中微通道结构对营养物输送能力的影响%Influence of Microfluidic Channels on Delivery of Nutrient in Cell-Laden Hydrogels

    Institute of Scientific and Technical Information of China (English)

    黄国友; 徐峰; 周丽宏; 周进雄; 陈咏梅; 卢天健


    为了优化栽细胞水凝胶中微通道的结构设计,通过数值模拟,系统地研究了孔隙率、微通道数目及排布方式等参数对营养物输送能力的影响.研究结果表明:在给定微通道数目下,微通道尺寸和间距均存在最优值,与此相对应的营养物输送能力最佳;当孔隙率或微通道数目较大时,微通道排布方式对营养物的输送能力无明显影响.通过参数优化,可以更好地提高微通道的营养物输送能力,尤其是保证远离微通道表面的细胞得到充足的营养物供应,为组织工程化组织中微通道结构的优化设计提供指导.%To optimize the structural parameters of microfluidic cell-laden hydrogels embedded with microchannels, a mathematical model is developed to systematically investigate the influence of microchannel size, inter-channel separation, number of channels and their distribution on nutrient transport in cell-laden hydrogels. The simulation results show that there exist the optimal microchannel size and inter-channel separation for enhanced nutrient utilization. While the porosity is fixed, the capability of nutrient transport is improved with the increasing channel number.The distribution of channels exerts slight effect on the nutrient delivery as the number of channels gets beyond 6. In addition, the nutrient transport can be enhanced by adjusting the diffusion properties of hydrogels. The present results provide useful guidance for the experimental design of microfluidic tissue constructs.

  1. Boron Toxicity in Plants and Phytoremediation of Boron-laden Soils%过量硼对植物的毒害及高硼土壤植物修复研究进展

    Institute of Scientific and Technical Information of China (English)

    刘春光; 何小娇


    硼作为一种植物必需元素,在土壤中过量存在会对植物产生毒害,硼对植物的毒害作用以及利用植物修复高硼土壤已经日益受到关注.目前,硼对不同类型植物的毒害特点,植物的耐受机制还不十分清楚.特别是对于硼污染的植物修复,其研究还处于起步阶段.本文分别从植物的表观症状、生理生化和基因水平等层次,综述了过量硼对植物的毒害,并从高耐受性、超富集能力植物筛选,以及转基因技术应用等角度回顾了硼污染的植物修复研究进展.在此基础上,提出了当前相关研究存在的主要问题,并对未来的研究进行了展望.%Boron is an essential element for plants, however, excessive boron in soil may exert toxic effects to plants. Recently, boron toxicity in plants as well as the phytoremediation of boron-laden soils has attracted much attention by both scientific and regulatory communities. But, boron toxicity in different plant species and the mechanisms of plant tolerance to boron are still unclear, and little information is available on phytoremediation of boron-laden soils. In this paper, boron toxicity in plants was reviewed from the perspectives of visible symptoms, physiological characteristics, and genetic variations. Besides, the application of phytoremediation to boron-contaminated soils was also illustrated, including the selection of high tolerance and/or hyperaccumulating plants, as well as the application of transgenic technologies. Finally, the main problems of current studies and the suggestions for future work were proposed.

  2. The long wavelength topography of Beethoven and Tolstoj basins, Mercury (United States)

    André, Sarah L.; Watters, Thomas R.; Robinson, Mark S.


    Topography derived from Mariner 10 stereo images is used to characterize the interior structure of two mercurian basins, Beethoven and Tolstoj. Beethoven and Tolstoj basins are shallow (~2.5 km and ~2 km deep, respectively) and relatively flat-floored. Beethoven basin has an interior topographic rise near the northwest margin. The topography of Beethoven and Tolstoj basins is similar to that of lunar mare-filled basins. Well-developed basin-concentric wrinkle ridges and arcuate graben associated with lunar mascons are absent in both Beethoven and Tolstoj basins. The lack of mascon tectonic features suggests that either 1) the mercurian basins have a relatively thin veneer of fill material, 2) Mercury's elastic lithosphere was too strong for significant lithospheric flexure and subsidence to occur, or 3) the basin fill material has little or no density contrast with the surrounding crust and thus exerts little net load on the mercurian lithosphere.

  3. Implication of drainage basin parameters of a tropical river basin of South India (United States)

    Babu, K. J.; Sreekumar, S.; Aslam, Arish


    Drainage morphometry provides quantitative description of the drainage system which is an important aspect of the characterisation of watersheds. Chalakudi River is one of the important rivers of the South India which has attracted attention of many environmental scientists recently because of the proposed Athirapally Hydel Project across the river. SRTM (Shuttle Radar Topographic Mission) data were used for preparing DEM (Digital Elevation Model), Aspect Map and Slope Map. Geographical Information System (GIS) was used for the evaluation of linear, areal and relief aspects of morphometric parameters. The study reveals that the terrain exhibits dentritic and trellis pattern of drainage. The Chalakudi River Basin has a total area of 1,448.73 km2 and is designated as seventh-order basin. The drainage density of the basin is estimated as 2.54 and the lower-order streams mostly dominate the basin. The high basin relief indicates high runoff and sediment transport. The elongation ratio of the Chalakudi Basin is estimated as 0.48 and indicates that the shape of the basin is elongated. The development of stream segments in the basin area is more or less effected by rainfall. Relief ratio indicates that the discharge capability of watershed is very high and the groundwater potential is meagre. The low value of drainage density in spite of mountainous relief indicates that the area is covered by dense vegetation and resistant rocks permeated by fractures and joints. These studies are helpful in watershed development planning and wise utilization of natural resources.

  4. Petroleum in the Junggar basin, northwestern China (United States)

    Taner, Irfan; Kamen-Kaye, Maurice; Meyerhoff, Arthur A.

    The Junggar basin occupies a large triangular area of some 130 000 km 2 in northwestern China. Situated between the Altay Shan (Altay Range) on the northeast and the Tian Shan (Tian Range) on the southwest, and between lesser ranges around the remainder of its periphery, the Junggar basin is completely intermontane. Its history as a basin began in the Permian, and continued as various uplifts and downwarps evolved. Through the Paleozoic the characteristics of the Junggar basin area were largely geosynclinal and marine. Its post-Permian development took place exclusively in continental regimes. Inhabitants of the Junggar basin have known and utilized its numerous oil and asphalt seeps and its spectacular spreads of asphalt for more than 2000 years, especially in the Karamay-Urho thrust belt near the northwestern rim. The first discovery of oil in the modern sense came at Dushanzi, one of the steeply folded anticlines of theÜrümqi foredeep near the southern rim. The first shallow oil in the Karamay-Urho thrust belt came in 1937, followed by commercial production in the Karamay field in 1955. Output continued to be modest until wells were drilled through local thrusts and reverse faults in the early 1980s. By 1985, cumulative production of the Karamay group of fields had reached 42,000,000 t (metric tonnes) (306,000,000 bbl), with a calculated minimum ultimate recovery of 280,000,000 t (2 billion bbl). Principal production comes from Permian and Triassic strata in continental facies. Apart from marine Mid and Upper Carboniferous strata, source rocks occur mainly in fine-grained lacustrine detrital beds of the Permian, the Triassic, the Jurassic and the Tertiary. Several uplifts and downwarps elsewhere in the Junggar basin remain to be drilled comprehensively. Results from such drilling may enhance the very important position that the Junggar already has attained in the hierarchy of China's onshore basins.

  5. Quantifying mesoscale eddies in the Lofoten Basin (United States)

    Raj, R. P.; Johannessen, J. A.; Eldevik, T.; Nilsen, J. E. Ø.; Halo, I.


    The Lofoten Basin is the most eddy rich region in the Norwegian Sea. In this paper, the characteristics of these eddies are investigated from a comprehensive database of nearly two decades of satellite altimeter data (1995-2013) together with Argo profiling floats and surface drifter data. An automated method identified 1695/1666 individual anticyclonic/cyclonic eddies in the Lofoten Basin from more than 10,000 altimeter-based eddy observations. The eddies are found to be predominantly generated and residing locally. The spatial distributions of lifetime, occurrence, generation sites, size, intensity, and drift of the eddies are studied in detail. The anticyclonic eddies in the Lofoten Basin are the most long-lived eddies (>60 days), especially in the western part of the basin. We reveal two hotspots of eddy occurrence on either side of the Lofoten Basin. Furthermore, we infer a cyclonic drift of eddies in the western Lofoten Basin. Barotropic energy conversion rates reveals energy transfer from the slope current to the eddies during winter. An automated colocation of surface drifters trapped inside the altimeter-based eddies are used to corroborate the orbital speed of the anticyclonic and cyclonic eddies. Moreover, the vertical structure of the altimeter-based eddies is examined using colocated Argo profiling float profiles. Combination of altimetry, Argo floats, and surface drifter data is therefore considered to be a promising observation-based approach for further studies of the role of eddies in transport of heat and biomass from the slope current to the Lofoten Basin.

  6. Basin-centered gas evaluated in Dnieper-Donets basin, Donbas foldbelt, Ukraine

    Energy Technology Data Exchange (ETDEWEB)

    Law, B.E. [Law (B.E.), Lakewood, CO (United States); Ulmishek, G.F.; Clayton, J.L. [Geological Survey, Denver, CO (United States); Kabyshev, B.P. [Ukrainian State Geological Inst., Chernigov (Ukraine); Pashova, N.T.; Krivosheya, V.A. [Ukrainian State Geological Inst., Poltava (Ukraine)


    An evaluation of thermal maturity, pore pressures, source rocks, reservoir quality, present-day temperatures, and fluid recovery data indicates the presence of a large basin-centered gas accumulation in the Dnieper-Donets basin (DDB) and Donbas foldbelt (DF) of eastern Ukraine. This unconventional accumulation covers an area of at least 35,000 sq km and extends vertically through as much as 7,000 m of Carboniferous rocks. The gas accumulation is similar, in many respects, to some North American accumulations such as Elmworth in the Alberta basin of western Canada, the Greater Green River basin of southwestern Wyoming, and the Anadarko basin of Oklahoma. Even though rigorous assessments of the recoverable gas have not been conducted in the region, a comparison of the dimensions of the accumulation to similar accumulations in the US indicates gas resources in excess of 100 tcf in place. The paper describes the geology, the reservoirs, source rocks, seals, and recommendations for further study.

  7. Chicxulub impact basin: Gravity characteristics and implications for basin morphology and deep structure (United States)

    Sharpton, Virgil L.; Burke, Kevin; Hall, Stuart A.; Lee, Scott; Marin, Luis E.; Suarez, Gerardo; Quezada-Muneton, Juan Manuel; Urrutia-Fucugauchi, Jaime


    The K-T-aged Chicxulub Impact Structure is buried beneath the Tertiary carbonate rocks of the Northern Yucatan Platform. Consequently its morphology and structure are poorly understood. Reprocessed Bouguer (onshore) and Free Air (offshore) gravity data over Northern Yucatan reveal that Chicxulub may be a 200-km-diameter multi-ring impact basin with at least three concentric basin rings. The positions of these rings follow the square root of 2 spacing rule derived empirically from analysis of multi-ring basins on other planets indicating that these rings probably correspond to now-buried topographic basin rings. A forward model of the gravity data along a radial transect from the southwest margin of the structure indicates that the Chicxulub gravity signature is compatible with this interpretation. We estimate the basin rim diameter to be 204 +/- 16 km and the central peak ring diameter (D) is 104 +/- 6 km.

  8. The Dependency of Probabilistic Tsunami Hazard Assessment on Magnitude Limits of Seismic Sources in the South China Sea and Adjoining Basins (United States)

    Li, Hongwei; Yuan, Ye; Xu, Zhiguo; Wang, Zongchen; Wang, Juncheng; Wang, Peitao; Gao, Yi; Hou, Jingming; Shan, Di


    The South China Sea (SCS) and its adjacent small basins including Sulu Sea and Celebes Sea are commonly identified as tsunami-prone region by its historical records on seismicity and tsunamis. However, quantification of tsunami hazard in the SCS region remained an intractable issue due to highly complex tectonic setting and multiple seismic sources within and surrounding this area. Probabilistic Tsunami Hazard Assessment (PTHA) is performed in the present study to evaluate tsunami hazard in the SCS region based on a brief review on seismological and tsunami records. 5 regional and local potential tsunami sources are tentatively identified, and earthquake catalogs are generated using Monte Carlo simulation following the Tapered Gutenberg-Richter relationship for each zone. Considering a lack of consensus on magnitude upper bound on each seismic source, as well as its critical role in PTHA, the major concern of the present study is to define the upper and lower limits of tsunami hazard in the SCS region comprehensively by adopting different corner magnitudes that could be derived by multiple principles and approaches, including TGR regression of historical catalog, fault-length scaling, tectonic and seismic moment balance, and repetition of historical largest event. The results show that tsunami hazard in the SCS and adjoining basins is subject to large variations when adopting different corner magnitudes, with the upper bounds 2-6 times of the lower. The probabilistic tsunami hazard maps for specified return periods reveal much higher threat from Cotabato Trench and Sulawesi Trench in the Celebes Sea, whereas tsunami hazard received by the coasts of the SCS and Sulu Sea is relatively moderate, yet non-negligible. By combining empirical method with numerical study of historical tsunami events, the present PTHA results are tentatively validated. The correspondence lends confidence to our study. Considering the proximity of major sources to population-laden cities

  9. 基于状态空间超级结构的多流股换热网络最优设计%Optimal design of multistream heat exchanger network based on state space superstructure

    Institute of Scientific and Technical Information of China (English)

    李永强; 王兵; 邹雄; 董宏光; 姚平经


    多流股换热器以其结构紧凑、高效低耗等特点,成为过程强化研究的热门领域,但对于多流股换热的过程与设备优势所在仍然值得商榷。基于多流股换热匹配改进状态空间超级结构,将多流股换热网络综合转化为超级换热器设计。首先,构造级联多流股换热器匹配过程操作算子,通过相邻换热流股匹配,传递温位效应,实现多流股间传热严格计算;借助热容流率混合分配机制,实现各流股间任意分混操作。然后,考虑散热因素,改进目标函数,引入冷热损失和保温材料费用项,清晰体现多流股换热器因换热面互相覆盖而带来的外表面封包优势。进而,建立相应非线性数学规划模型,实现公用工程、设备投资、冷热损耗同步优化。最终,通过文献示例对所提方法可行性与优越性进行验证。%Multistream heat exchanger (MHEX) has attracted attention in the process intensification field with its compact structure, high efficiency and low heat loss. However, the potential advantages of its process and equipment are still worth discussing. An improved State-space superstructure based on MHEXs process operator (PO) was proposed to convert the network synthesis into a super-exchanger design. Hierarchy matching MHEXs PO was constructed, and the strict heat transfer calculation among multiple streams was implemented through temperature coordinated effect between adjacent streams. Arbitrary splitting and mixing of any stream was achieved by corresponding mixers and splitters in distribution network (DN). The objective function was ameliorated by taking heat loss into consideration. Through introducing the cost of heat loss and thermal insulation material, the external surface envelope advantage of MHEX was presented clearly owing to coverage between adjacent heat-transfer surfaces. Then, a corresponding nonlinear programming (NLP) mathematical model was

  10. Desert basins of the Southwest (United States)

    Leake, Stanley A.; Konieczki, Alice D.; Rees, Julie A.H.


    Ground water is among the Nation’s most important natural resources. It provides drinking water to urban and rural communities, supports irrigation and industry, sustains the flow of streams and rivers, and maintains riparian and wetland ecosystems. In many areas of the Nation, the future sustainability of ground-water resources is at risk from overuse and contamination. Because ground-water systems typically respond slowly to human actions, a long-term perspective is needed to manage this valuable resource. This publication is one in a series of fact sheets that describe ground-water-resource issues across the United States, as well as some of the activities of the U.S. Geological Survey that provide information to help others develop, manage, and protect ground-water resources in a sustainable manner. Ground-water resources in the Southwest are among the most overused in the United States. Natural recharge to aquifers is low and pumping in many areas has resulted in lowering of water tables. The consequences of large-scale removal of water from storage are becoming increasingly evident. These consequences include land subsidence; loss of springs, streams, wetlands and associated habitat; and degradation of water quality. Water managers are now seeking better ways of managing ground-water resources while looking for supplemental sources of water. This fact sheet reviews basic information on ground water in the desert basins of the Southwest. Also described are some activities of the U.S. Geological Survey (USGS) that are providing scientific information for sustainable management of ground-water resources in the Southwest. Ground-water sustainability is defined as developing and using ground water in a way that can be maintained for an indefinite time without causing unacceptable environmental, economic, or social consequences.

  11. Impact melt of the lunar Crisium multiring basin (United States)

    Spudis, P. D.; Sliz, M. U.


    New geological mapping of the Crisium basin on the Moon has revealed exposures of the basin impact melt sheet. The melt sheet has a feldspathic highland composition, somewhat more mafic than the melt sheet of the Orientale basin, but less mafic than comparable deposits around the Imbrium basin. These newly recognized deposits would be ideal locations to directly sample Crisium basin impact melt, material whose study would yield insight into the composition of the lunar crust, the time of formation of the basin, and the large impact process.

  12. Groundwater quality in the Northern Coast Ranges Basins, California (United States)

    Mathany, Timothy M.; Belitz, Kenneth


    The Northern Coast Ranges (NOCO) study unit is 633 square miles and consists of 35 groundwater basins and subbasins (California Department of Water Resources, 2003; Mathany and Belitz, 2015). These basins and subbasins were grouped into two study areas based primarily on locality. The groundwater basins and subbasins located inland, not adjacent to the Pacific Ocean, were aggregated into the Interior Basins (NOCO-IN) study area. The groundwater basins and subbasins adjacent to the Pacific Ocean were aggregated into the Coastal Basins (NOCO-CO) study area (Mathany and others, 2011).

  13. Multiple nested basin boundaries in nonlinear driven oscillators☆ (United States)

    Zhang, Yongxiang; Xie, Xiangpeng; Luo, Guanwei


    A special type of basins of attraction for high-period coexisting attractors is investigated, which basin boundaries possess multiple nested structures in a driven oscillator. We analyze the global organization of basins and discuss the mechanism for the appearance of layered structures. The unstable periodic orbits and unstable limit cycle are also detected in the oscillator. The basin organization is governed by the ordering of regular saddles and the regular saddle connections are the interrupted by the unstable limit cycle. Wada basin boundary with different Wada number is discovered. Wada basin boundaries for the hidden and rare attractors are also verified.

  14. Cell-laden poly(ɛ-caprolactone)/alginate hybrid scaffolds fabricated by an aerosol cross-linking process for obtaining homogeneous cell distribution: fabrication, seeding efficiency, and cell proliferation and distribution. (United States)

    Lee, HyeongJin; Ahn, SeungHyun; Bonassar, Lawrence J; Chun, Wook; Kim, GeunHyung


    Generally, solid-freeform fabricated scaffolds show a controllable pore structure (pore size, porosity, pore connectivity, and permeability) and mechanical properties by using computer-aided techniques. Although the scaffolds can provide repeated and appropriate pore structures for tissue regeneration, they have a low biological activity, such as low cell-seeding efficiency and nonuniform cell density in the scaffold interior after a long culture period, due to a large pore size and completely open pores. Here we fabricated three different poly(ɛ-caprolactone) (PCL)/alginate scaffolds: (1) a rapid prototyped porous PCL scaffold coated with an alginate, (2) the same PCL scaffold coated with a mixture of alginate and cells, and (3) a multidispensed hybrid PCL/alginate scaffold embedded with cell-laden alginate struts. The three scaffolds had similar micropore structures (pore size = 430-580 μm, porosity = 62%-68%, square pore shape). Preosteoblast cells (MC3T3-E1) were used at the same cell density in each scaffold. By measuring cell-seeding efficiency, cell viability, and cell distribution after various periods of culturing, we sought to determine which scaffold was more appropriate for homogeneously regenerated tissues.


    Institute of Scientific and Technical Information of China (English)

    Wenxue LI; Yuanfeng ZHANG; Cuiping ZHANG


    Observation of the operation of the Sanmenxia Reservoir on the Yellow River has led to the conclusion that to preserve a certain effective storage volume for reservoirs built on heavily silt-laden rivers is feasible if the reservoir is operated according to the principle known as "storing the clear water and discharging the muddy flow". The relative stability of the bed elevation at the end of the backwater and the reservoir's erosion and deposition equilibrium depend on the compatibility of the pool level maintained in non-flood seasons with the conditions of flow and sediment load during flood seasons. Operating the reservoir to regulate the flood and sediment load during flood seasons can reduce the rate of aggradation in the Lower Yellow River. The basic condition for applying the operation mode of "storing the clear water and discharging the muddy flow" is that a sufficient amount of water should be used for discharging sediment during flood seasons. Under the condition of extremely low flow years, reservoir sedimentation cannot be avoided even if this operation mode is adopted.

  16. Turbulent Flow Measurement in Vortex Settling Basin

    Directory of Open Access Journals (Sweden)

    Jafar Chapokpour


    Full Text Available This paper presents the findings of an experimental study on the three-dimensional turbulent flow field in vortex settling basin. An ADV (Acoustic Doppler Velocity Meter were used to catch 3D velocitycomponents inside the basin. Detailed measurements of time-averaged velocity components, turbulent intensity components and turbulent kinetic energy were determined at different radial sections of chamber. Also the normalized time averaged absolute velocity of 3D components in contour type exhibition were conducted and it was found that the absolute velocity generally is influenced by u component of flow. It trends from high magnitude in basin center to the constant magnitude in basin side wall. The normalized turbulent intensity ofthree components was investigated individually. It was found that intensity of 3D components in vicinity of central air core is higher than other regions, decreasing by moving towards basin sidewall except for the sections that influenced directly by entrance flow jet and sidewall exiting overflow. The results of turbulence kinetic energy also had the same interpretation like turbulence intensity and affected by the same boundary conditions which cover turbulence intensity of 3 velocity components overly.

  17. A geological history of the Turkana Basin. (United States)

    Feibel, Craig S


    The Turkana Basin preserves a long and detailed record of biotic evolution, cultural development, and rift valley geology in its sedimentary strata. Before the formation of the modern basin, Cretaceous fluvial systems, Paleogene lakes, and Oligo-Miocene volcano-sedimentary sequences left fossil-bearing strata in the region. These deposits were in part related to an early system of rift basins that stretched from Sudan to the Indian Ocean. The present-day basin has its origins in Pliocene tectonic developments of the modern rift, with subsidence making room for more than one kilometer of Plio-Pleistocene strata. Much of this sequence belongs to the Omo Group, richly fossiliferous sediments associated with the ancestral Omo River and its tributaries. Modern Lake Turkana has a record stretching back more than 200 thousand years, with earlier lake phases throughout the Plio-Pleistocene. The geologic history of the basin is one of dynamic landscapes responding to environmental influences, including tectonics, volcanic activity and climate.

  18. Tectonics in the Northwestern West Philippine Basin

    Institute of Scientific and Technical Information of China (English)

    Ni Xianglong; Wu Shiguo; Shinjo Ryuichi


    The West Philippine basin (WPB) is a currently inactive marginal basin belonging to Philippine Sea plate, which has a complex formation history and various crust structures. Based on gravity, magnetic and seismic data, the tectonics in West Philippine basin is characterized by amagnma spreading stage and strike slip fractures. NNE trending Okinawa-Luzon fracture zone is a large fracture zone with apparent geomorphology and shows a right-handed movement. The results of joint gravity-magnetic-seismic inversion suggest that the Okinawa-Luzon fracture zone has intensive deformation and is a transform fault. Western existence of the NW trending fractures under Ryukyu Islands Arc is the main cause of the differences between south and north Okinawa Trough. The Urdaneta plateau is not a remained arc, but remnant of mantle plume although its lava chemistry is similar to oceanic island basalt (OIB).

  19. Spatial Preference Heterogeneity for Integrated River Basin Management: The Case of the Shiyang River Basin, China

    Directory of Open Access Journals (Sweden)

    Fanus Asefaw Aregay


    Full Text Available Integrated river basin management (IRBM programs have been launched in most parts of China to ease escalating environmental degradation. Meanwhile, little is known about the benefits from and the support for these programs. This paper presents a case study of the preference heterogeneity for IRBM in the Shiyang River Basin, China, as measured by the Willingness to Pay (WTP, for a set of major restoration attributes. A discrete choice analysis of relevant restoration attributes was conducted. The results based on a sample of 1012 households in the whole basin show that, on average, there is significant support for integrated ecological restoration as indicated by significant WTP for all ecological attributes. However, residential location induced preference heterogeneities are prevalent. Generally, compared to upper-basin residents, middle sub-basin residents have lower mean WTP while lower sub-basin residents express higher mean WTP. The disparity in utility is partially explained by the difference in ecological and socio-economic status of the residents. In conclusion, estimating welfare benefit of IRBM projects based on sample responses from a specific sub-section of the basin only may either understate or overstate the welfare estimate.

  20. Mercury and Methylmercury concentrations and loads in Cache Creek Basin, California, January 2000 through May 2001 (United States)

    Domagalski, Joseph L.; Alpers, Charles N.; Slotton, Darrell G.; Suchanek, Thomas H.; Ayers, Shaun M.


    Concentrations and mass loads of total mercury and methylmercury in streams draining abandoned mercury mines and near geothermal discharge in Cache Creek Basin, California, were measured during a 17-month period from January 2000 through May 2001. Rainfall and runoff averages during the study period were lower than long-term averages. Mass loads of mercury and methylmercury from upstream sources to downstream receiving waters, such as San Francisco Bay, were generally the highest during or after winter rainfall events. During the study period, mass loads of mercury and methylmercury from geothermal sources tended to be greater than those from abandoned mining areas because of a lack of large precipitation events capable of mobilizing significant amounts of either mercury-laden sediment or dissolved mercury and methylmercury from mine waste. Streambed sediments of Cache Creek are a source of mercury and methylmercury to downstream receiving bodies of water such as the Delta of the San Joaquin and Sacramento Rivers. Much of the mercury in these sediments was deposited over the last 150 years by erosion and stream discharge from abandoned mines or by continuous discharges from geothermal areas. Several geochemical constituents were useful as natural tracers for mining and geothermal areas. These constituents included aqueous concentrations of boron, chloride, lithium, and sulfate, and the stable isotopes of hydrogen and oxygen in water. Stable isotopes of water in areas draining geothermal discharges were enriched with more oxygen-18 relative to oxygen-16 than meteoric waters, whereas the enrichment by stable isotopes of water from much of the runoff from abandoned mines was similar to that of meteoric water. Geochemical signatures from stable isotopes and trace-element concentrations may be useful as tracers of total mercury or methylmercury from specific locations; however, mercury and methylmercury are not conservatively transported. A distinct mixing trend of

  1. Exploration Experience and Problem concerning Deep Basin Gas in the Ordos Basin

    Institute of Scientific and Technical Information of China (English)



    Deep basin gas (DBG) reservoirs, in view of the characteristics of their main parts containing gas, are a type of subtle stratigraphic lithologic traps. But they have different reservoir-forming principles, especially in the distribution of oil, gas and water. DBG is characterized by gas-water invertion, namely the water located above the gas; however, normal non-anticline subtle reservoirs have normal distribution of gas and water, namely the water located under the gas. The theory of DBG broke the conventional exploration idea that gas is usually found in the high part of reservoir and water is under the gas. So, it provided a wide field and a new idea for the exploration of natural gas. Recently Ben E. Law (2002), in his article entitled "Basin-centered Gas Systems", discussed global DBG systemically. He listed 72 basins or areas containing known or suspected DBG, covering North America, South America, Europe, Asia-Pacific, South Asia, Middle East and Africa. Ordos basin, the Sichuan basin and the Jungar basin in China are presented and assumed to be of very high possibility. In China more attention has been paid to the research and exploration of DBG in the past years. The symposiums on DBG were held twice, in Guangzhou in 1998 and in Xi'an in 2000 respectively. In 2002 in particular, the publication of the book named Deep Basin Gas in China by Professor Wangtao indicated that China has entered a new stage in the research on DBG. Meanwhile, it is more cheering that the exploration of DBG in the Ordos Basin has achieved remarkable success. Therefore, analyzing the exploration experiences and problems regarding the Ordos basin will promote the exploration and research of DBG in China.

  2. Palaeoclimatological perspective on river basin hydrometeorology: case of the Mekong Basin (United States)

    Räsänen, T. A.; Lehr, C.; Mellin, I.; Ward, P. J.; Kummu, M.


    Globally, there have been many extreme weather events in recent decades. A challenge has been to determine whether these extreme weather events have increased in number and intensity compared to the past. This challenge is made more difficult due to the lack of long-term instrumental data, particularly in terms of river discharge, in many regions including Southeast Asia. Thus our main aim in this paper is to develop a river basin scale approach for assessing interannual hydrometeorological and discharge variability on long, palaeological, time scales. For the development of the basin-wide approach, we used the Mekong River basin as a case study area, although the approach is also intended to be applicable to other basins. Firstly, we derived a basin-wide Palmer Drought Severity Index (PDSI) from the Monsoon Asia Drought Atlas (MADA). Secondly, we compared the basin-wide PDSI with measured discharge to validate our approach. Thirdly, we used basin-wide PDSI to analyse the hydrometeorology and discharge of the case study area over the study period of 1300-2005. For the discharge-MADA comparison and hydrometeorological analyses, we used methods such as linear correlations, smoothing, moving window variances, Levene type tests for variances, and wavelet analyses. We found that the developed basin-wide approach based on MADA can be used for assessing long-term average conditions and interannual variability for river basin hydrometeorology and discharge. It provides a tool for studying interannual discharge variability on a palaeological time scale, and therefore the approach contributes to a better understanding of discharge variability during the most recent decades. Our case study revealed that the Mekong has experienced exceptional levels of interannual variability during the post-1950 period, which could not be observed in any other part of the study period. The increased variability was found to be at least partly associated with increased El Niño Southern

  3. Paleohydrogeology of the San Joaquin basin, California (United States)

    Wilson, A.M.; Garven, G.; Boles, J.R.


    Mass transport can have a significant effect on chemical diagenetic processes in sedimentary basins. This paper presents results from the first part of a study that was designed to explore the role of an evolving hydrodynamic system in driving mass transport and chemical diagenesis, using the San Joaquin basin of California as a field area. We use coupled hydrogeologic models to establish the paleohydrogeology, thermal history, and behavior of nonreactive solutes in the basin. These models rely on extensive geological information and account for variable-density fluid flow, heat transport, solute transport, tectonic uplift, sediment compaction, and clay dehydration. In our numerical simulations, tectonic uplift and ocean regression led to large-scale changes in fluid flow and composition by strengthening topography-driven fluid flow and allowing deep influx of fresh ground water in the San Joaquin basin. Sediment compaction due to rapid deposition created moderate overpressures, leading to upward flow from depth. The unusual distribution of salinity in the basin reflects influx of fresh ground water to depths of as much as 2 km and dilution of saline fluids by dehydration reactions at depths greater than ???2.5 km. Simulations projecting the future salinity of the basin show marine salinities persisting for more than 10 m.y. after ocean regression. Results also show a change from topography-to compaction-driven flow in the Stevens Sandstone at ca. 5 Ma that coincides with an observed change in the diagenetic sequence. Results of this investigation provide a framework for future hydrologic research exploring the link between fluid flow and diagenesis.

  4. Geothermal structure of Australia's east coast basins (United States)

    Danis, C. R.; O'Neill, C.


    The east coast sedimentary basins of Australia formed on an active margin of eastern Gondwana, and constitute an important hydrocarbon resource. The 1600km long Sydney-Gunnedah-Bowen Basin (SGBB) is largest east coast basin system, with thick Permian to Jurassic sedimentary successions overlying Palaeozoic basement rocks. The SGBB has been the focus of renewed geothermal exploration interest, however, the thermal state and geothermal potential of the system is largely unconstrained. Geothermal exploration programs require an accurate estimate of subsurface temperature information, in addition to favourable geology, to make informed decisions on potential targe developments. Primarily temperature information comes from downhole measurements, generally non-equilibrated, which are traditionally extrapolated to depth, however such extrapolation does not take into account variations in geological structure or thermal conductivity. Here we import deep 3D geological models into finite element conduction simulations, using the code Underworld, to calculate the deep thermal structure of the basin system. Underworld allows us to incorporate complex, detailed geological architecture models, incorporating different material properties for different layers, with variable temperature and depth-dependent properties. We adopt a fixed top boundary temperature on a variable topographic surface, and vary the bottom surface boundary condition, to converge of models which satisfy equilibrated downhole temperature measurement constraints. We find coal plays an important role in insulating sedimentary basins. Heat refracts around the coal interval and produces elevated temperatures beneath thick sediments, especially where thick coal intervals are present. This workflow has been formalized into an Underworld geothermal model library, enabling model centric computational workflows. Using the imported model architecture from the geology, data can be continuously updated and added to the

  5. Avian cholera in Nebraska's Rainwater Basin (United States)

    Windingstad, R.M.; Hurt, J.J.; Trout, A.K.; Cary, J.


    The first report of avian cholera in North America occurred in northwestern Texas in winter 1944 (Quortrup et al. 1946). In 1975, mortality from avian cholera occurred for the first time in waterfowl in the Rainwater Basin of Nebraska when an estimated 25,000 birds died (Zinkl et al. 1977). Avian cholera has continued to cause mortality in wild birds in specific areas of the Basin each spring since. Losses of waterfowl from avian cholera continue to be much greater in some of the wetlands in the western part of the Basin than in the east. Several wetlands in the west have consistently higher mortality and are most often the wetlands where initial mortality is noticed each spring (Figure 1). The establishment of this disease in Nebraska is of considerable concern because of the importance of the Rainwater Basin as a spring staging area for waterfowl migrating to their breeding grounds. The wetlands in this area are on a major migration route used by an estimated 5 to 9 million ducks and several hundred thousand geese. A large portion of the western mid-continental greater white-fronted goose (Anser albifrons) population stage in the Basin each spring. Occasionally, whooping cranes (Grus americana) use these wetlands during migration, and lesser sandhill cranes (Grus canadensis) staging on the nearby Platte River sometimes use wetlands where avian cholera occurs (Anonymous 1981). Our objectives were to determine whether certain water quality variables in the Rainwater Basin differed between areas of high and low avian cholera incidence. These results would then be used for laboratory studies involving the survivability of Pasteurella multocida, the causative bacterium of avian cholera. Those studies will be reported elsewhere.

  6. Alluvial basin statistics of the Southwest Principal Aquifers (SWPA) study. (United States)

    U.S. Geological Survey, Department of the Interior — SWPA_alvbsn is a vector dataset of alluvial-fill basin statistics for the Southwest United States. Statistics for each basin include physical details such as area,...

  7. Three-phase tectonic evolution of the Andaman backarc basin

    Digital Repository Service at National Institute of Oceanography (India)

    KameshRaju, K.A

    A three-phase evolutionary scheme since Late Oligocene for the Andaman backarc basin is proposed based on the multibeam swath bathymetry, magnetic and seismological data. A SW–NE trending spreading ridge bisects the basin. The tectonic evolution...

  8. Basin and Range Province, Western US, USGS Grids #5 (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These grid files were used to produce gravity and basin depth maps of the Basin and Range Province, western United States. The maps show gravity values and modeled...

  9. Basin and Range Province, Western US, USGS Grids #3 (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These grid files were used to produce gravity and basin depth maps of the Basin and Range Province, western United States. The maps show gravity values and modeled...

  10. Basin and Range Province, Western US, USGS Grids, #1 (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These grid files were used to produce gravity and basin depth maps of the Basin and Range Province, western United States. The maps show gravity values and modeled...

  11. Ferromanganese nodules from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Jauhari, P.; Pattan, J.N.

    In order to delineate a mine site for ferromanganese nodules, extensive surveys were conducted in Central Indian Ocean Basin. Mapping of the basin by multibeam swath bathymetry (Hydrosweep) has revealed many new bottom relief features...

  12. Water resources of the Chad Basin Region

    Directory of Open Access Journals (Sweden)

    Franklyn R. Kaloko


    Full Text Available River basin development is seen as a very effective means of improving agricultural productivity. In the Chad Basin area of the Sahelian Zone of the West African Sub-Region, the water resources have been harnessed to ensure viable agricultural programmes for Nigeria. However,the resultant successes have met by many problems that range from physical to socio-economic and of which water losses have been the most threatening. The study has called for the use of Hexa.deconal (C1-OH film on the water surface of the Chad as a means of reducing evaporation.

  13. The classification of polynomial basins of infinity

    CERN Document Server

    DeMarco, Laura


    We consider the problem of classifying the dynamics of complex polynomials $f: \\mathbb{C} \\to \\mathbb{C}$ restricted to their basins of infinity. We synthesize existing combinatorial tools --- tableaux, trees, and laminations --- into a new invariant of basin dynamics we call the pictograph. For polynomials with all critical points escaping to infinity, we obtain a complete description of the set of topological conjugacy classes. We give an algorithm for constructing abstract pictographs, and we provide an inductive algorithm for counting topological conjugacy classes with a given pictograph.

  14. A global distributed basin morphometric dataset (United States)

    Shen, Xinyi; Anagnostou, Emmanouil N.; Mei, Yiwen; Hong, Yang


    Basin morphometry is vital information for relating storms to hydrologic hazards, such as landslides and floods. In this paper we present the first comprehensive global dataset of distributed basin morphometry at 30 arc seconds resolution. The dataset includes nine prime morphometric variables; in addition we present formulas for generating twenty-one additional morphometric variables based on combination of the prime variables. The dataset can aid different applications including studies of land-atmosphere interaction, and modelling of floods and droughts for sustainable water management. The validity of the dataset has been consolidated by successfully repeating the Hack's law.

  15. Tectonic differences between eastern and western sub-basins of the Qiongdongnan Basin and their dynamics (United States)

    Liu, Jianbao; Sun, Zhen; Wang, Zhenfeng; Sun, Zhipeng; Zhao, Zhongxian; Wang, Zhangwen; Zhang, Cuimei; Qiu, Ning; Zhang, Jiangyang


    The central depression of the Qiongdongnan Basin can be divided into the eastern and western sub-basins by the Lingshui-Songnan paleo-uplift. To the northwest, the orientation of the faults turns from NE, to EW, and later to NW; In the southwest, the orientation of the faults turns from NE, to NNE, and then to NW, making the central depression much wider towards the west. In the eastern sub-basin, the NE-striking faults and the EW-striking faults made up an echelon, making the central depression turn wider towards the east. Fault activity rates indicate that faulting spreads gradually from both the east and west sides to the middle of the basin. Hence, extensional stress in the eastern sub-basin may be related to the South China Sea spreading system, whereas the western sub-basin was more under the effect of the activity of the Red River Fault. The extreme crustal stretching in the eastern sub-basin was probably related to magmatic setting. It seems that there are three periods of magmatic events that occurred in the eastern sub-basin. In the eastern part of the southern depression, the deformed strata indicate that the magma may have intruded into the strata along faults around T60 (23.3 Ma). The second magmatic event occurred earlier than 10.5 Ma, which induced the accelerated subsidence. The final magmatic event commenced later than 10 Ma, which led to today's high heat flow. As for the western sub-basin, the crust thickened southward, and there seemed to be a southeastward lower crustal flow, which happened during continental breakup which was possibly superimposed by a later lower crustal flow induced by the isostatic compensation of massive sedimentation caused by the right lateral slipping of the Red River Fault. Under the huge thick sediment, super pressure developed in the western sub-basin. In summary, the eastern sub-basin was mainly affected by the South China Sea spreading system and a magma setting, whereas the western sub-basin had a closer

  16. SimBasin: serious gaming for integrated decision-making in the Magdalena-Cauca basin (United States)

    Craven, Joanne; Angarita, Hector; Corzo, Gerald


    The Magdalena-Cauca macrobasin covers 24% of the land area of Colombia, and provides more than half of the country's economic potential. The basin is also home a large proportion of Colombia's biodiversity. These conflicting demands have led to problems in the basin, including a dramatic fall in fish populations, additional flooding (such as the severe nationwide floods caused by the La Niña phenomenon in 2011), and habitat loss. It is generally believed that the solution to these conflicts is to manage the basin in a more integrated way, and bridge the gaps between decision-makers in different sectors and scientists. To this end, inter-ministerial agreements are being formulated and a decision support system is being developed by The Nature Conservancy Colombia. To engage stakeholders in this process SimBasin, a "serious game", has been developed. It is intended to act as a catalyst for bringing stakeholders together, an illustration of the uncertainties, relationships and feedbacks in the basin, and an accessible introduction to modelling and decision support for non-experts. During the game, groups of participants are led through a 30 year future development of the basin, during which they take decisions about the development of the basin and see the impacts on four different sectors: agriculture, hydropower, flood risk, and environment. These impacts are displayed through seven indicators, which players should try to maintain above critical thresholds. To communicate the effects of uncertainty and climate variability, players see the actual value of the indicator and also a band of possible values, so they can see if their decisions have actually reduced risk or if they just "got lucky". The game works as a layer on top of a WEAP water resources model of the basin, adapted from a basin-wide model already created, so the fictional game basin is conceptually similar to the Magdalena-Cauca basin. The game is freely available online, and new applications are being

  17. Morphometric analysis of Suketi river basin, Himachal Himalaya, India

    Indian Academy of Sciences (India)

    Anil M Pophare; Umesh S Balpande


    Suketi river basin is located in the Mandi district of Himachal Pradesh, India. It encompasses a central inter-montane valley and surrounding mountainous terrain in the Lower Himachal Himalaya. Morphometric analysis of the Suketi river basin was carried out to study its drainage characteristics and overall groundwater resource potential. The entire Suketi river basin has been divided into five sub-basins based on the catchment areas of Suketi trunk stream and its major tributaries. Quantitative assessment of each sub-basin was carried out for its linear, areal, and relief aspects. The analysis reveals that the drainage network of the entire Suketi river basin constitutes a 7th order basin. Out of five sub-basins, Kansa khad sub-basin (KKSB), Gangli khad sub-basin (GKSB) and Ratti khad sub-basin (RKSB) are 5th order subbasins. The Dadour khad sub-basin (DKSB) is 6th order sub-basin, while Suketi trunk stream sub-basin (STSSB) is a 7th order sub-basin. The entire drainage basin area reflects late youth to early mature stage of development of the fluvial geomorphic cycle, which is dominated by rain and snow fed lower order streams. It has low stream frequency (Fs) and moderate drainage density (Dd) of 2.69 km/km2. Bifurcation ratios (Rb) of various stream orders indicate that streams up to 3rd order are surging through highly dissected mountainous terrain, which facilitates high overland flow and less recharge into the subsurface resulting in low groundwater potential in the zones of 1st, 2nd, and 3rd order streams of the Suketi river basin. The circulatory ratio (Rc) of 0.65 and elongation ratio (Re) of 0.80 show elongated nature of the Suketi river basin, while infiltration number (If) of 10.66 indicates dominance of relief features and low groundwater potential in the high altitude mountainous terrain. The asymmetry factor (Af) of Suketi river basin indicates that the palaeo-tectonic tilting, at drainage basin scale, was towards the downstream right side of the

  18. Microstructural comparison between Nb- and Ta-systems in Li{sub 1+x−y}M{sub 1−x−3y}Ti{sub x+4y}O{sub 3} (M = Nb{sup 5+}, Ta{sup 5+}) solid solution with superstructure

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Hiromi, E-mail: [Cooperative Research Facility Center, Toyohashi University of Technology, Toyohashi 441-8580 (Japan); Department of Environmental and Life Sciences, Toyohashi University of Technology, Toyohashi 441-8580 (Japan); Suehiro, Shiho; Furuya, Syohei [Department of Environmental and Life Sciences, Toyohashi University of Technology, Toyohashi 441-8580 (Japan); Fukuda, Koichiro [Department of Materials Science and Engineering, Nagoya Institute of Technology, Nagoya 466-8555 (Japan)


    Highlights: • The composition range of superstructure formed by self-organization was clarified. • The detailed microstructures were analyzed using SEM, XRD and TEM. • The microstructural difference between LNT and LTT was determined. • The superstructure’s formation speed, period and area were controlled by Ti content. - Abstract: We successfully synthesized Li{sub 1+x−y}M{sub 1−x−3y}Ti{sub x+4y}O{sub 3} solid solutions (M = Nb or Ta, LMT, 0.07 ⩽ x ⩽ 0.33, 0 ⩽ y ⩽ 0.175) that have a superstructure, using a conventional electric furnace. The synthesizing time depended on the Ti content, and annealing was repeated for 24–264 h until a homogeneous structure was formed by the insertion of periodical intergrowth layers. We characterized the LMT solid solutions, from micro-scale to nano-scale, using X-ray diffraction, a scanning electron microscope, and a transmission electron microscope. The period of the intergrowth layer was controlled by the Ti content. LNT’s period of the intergrowth layer was narrower than that of LTT in the real lattice when the Ti content was the same. The narrowest interplanar distance (1.82 nm) of the intergrowth layer was formed in Li{sub 0.935}Ta{sub 0.365}Ti{sub 0.810}O{sub 3}. The widest distance (14.3 nm) appeared in Li{sub 1.11}Nb{sub 0.89}Ti{sub 0.11}O{sub 3}, but no such wide period formed in the Ta-system.

  19. Seismic evidence of tectonic stresses; Implications for basin reconstruction

    NARCIS (Netherlands)

    Tigrek, S.


    Stress and strain are two important rheological parameters that have impacts on basin development and dynamics. The dynamic evolution of a basin depends on the spatial and temporal changes in the stresses. How to determine the reference state of stress within a sedimentary basin and the magnitude of

  20. Riddled Basins of Attraction for Synchronized Type-I Intermittency

    DEFF Research Database (Denmark)

    Mancher, Martin; Nordahn, Morten; Mosekilde, Erik;


    Chaotic mortion resticted to an invariant subspace of total phase space may be associated with basins of attraction that are riddled with holes belonging to the basin of another limiting state. We study the emergence of such basins of two coupled one-dimensional maps, each exhibiting type...

  1. Detailed bathymetric surveys in the central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Kodagali, V.N.; KameshRaju, K.A.; Ramprasad, T.; George, P.; Jaisankar, S.

    Over 420,000 line kilometers of echo-sounding data was collected in the Central Indian Basin. This data was digitized, merged with navigation data and a detailed bathymetric map of the Basin was prepared. The Basin can be broadly classified...

  2. Notice of release of 'Trailhead II' basin wildrye (United States)

    'Trailhead II' basin wildrye [Leymus cinereus (Scribn. & Merr.) A. Love] is a tetraploid basin wildrye release for use in re-vegetation efforts on rangelands of western North America. Trailhead II is the result of two cycles of recurrent selection within the basin wildrye cultivar 'Trailhead' for r...

  3. 75 FR 11000 - Security Zone; Freeport LNG Basin, Freeport, TX (United States)


    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA87 Security Zone; Freeport LNG Basin, Freeport, TX AGENCY... in the Freeport LNG Basin. This security zone is needed to protect vessels, waterfront facilities... notice of proposed rulemaking (NPRM) entitled Security Zone; Freeport LNG Basin, Freeport, TX in...

  4. 76 FR 61382 - Colorado River Basin Salinity Control Advisory Council (United States)


    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. ] SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974 (Pub....

  5. 75 FR 25877 - Colorado River Basin Salinity Control Advisory Council (United States)


    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control ] Act of 1974...

  6. 78 FR 70574 - Colorado River Basin Salinity Control Advisory Council (United States)


    ....20350010.REG0000, RR04084000] Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974 (Pub....

  7. 77 FR 23508 - Colorado River Basin Salinity Control Advisory Council (United States)


    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974 (Pub....

  8. 75 FR 27360 - Colorado River Basin Salinity Control Advisory Council (United States)


    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974 (Pub....

  9. 75 FR 66389 - Colorado River Basin Salinity Control Advisory Council (United States)


    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974 (Pub....

  10. 76 FR 24515 - Colorado River Basin Salinity Control Advisory Council (United States)


    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of... Committee Act, the Bureau of Reclamation announces that the Colorado River Basin Salinity Control Advisory...) 524-3826; e-mail at: . SUPPLEMENTARY INFORMATION: The Colorado River Basin...

  11. 77 FR 61784 - Colorado River Basin Salinity Control Advisory Council (United States)


    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974 (Pub....

  12. 78 FR 23784 - Colorado River Basin Salinity Control Advisory Council (United States)


    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974...


    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard


    The principal research effort for Year 3 of the project is basin modeling and petroleum system identification, comparative basin evaluation and resource assessment. In the first six (6) months of Year 3, the research focus is on basin modeling and petroleum system identification and the remainder of the year the emphasis is on the comparative basin evaluation and resource assessment. No major problems have been encountered to date, and the project is on schedule.

  14. Klamath Basin Restoration Agreement Off-Project Water Program Sub-basin Analysis Flow Statistics (United States)


  15. Strain localisation during basin inversion in the North German basin and the Donbas Fold Belt

    Energy Technology Data Exchange (ETDEWEB)

    Maystrenko, Y.; Bayer, U. [GFZ Potsdam (Germany); Gajewski, D. [Hamburg Univ. (Germany). Inst. fuer Geophysik


    The DEKORP Basin'96 and the DOBREflection-200 lines provide two world wide exceptional examples of successfully performed deep seismic lines. This is especially true for the inversion of the two basins by representing probably two stages in the amount of shortening accompanied by strain localization causing decoupling of the sedimentary fill from the deeper crust within the North East German basin and the Donbas Fold Belt. High-velocity bodies are observed in the DEKORP Basin'96 and DOBREflection-2000 reflection seismic lines. These bodies may have been essential in localizing strain localisation by counteracting compressive forces and causing folding and finally failure and faulting of the deep crust. (orig.)

  16. Basin Subsegments from LDEQ source data, Geographic NAD83, LOSCO (2004) [basin_subsegments_LDEQ_2004 (United States)

    Louisiana Geographic Information Center — This is a polygon data set of watershed basin subsegments for Louisiana. The dataset was developed for the LDEQ Office of Water Resources' watershed assessment and...

  17. Klamath Basin Water Rights Place of Use (United States)

    U.S. Geological Survey, Department of the Interior — Hydrological Information Products for the Off-Project Water Program of the Klamath Basin Restoration Agreement U.S. Geological Survey Open-File Report 2012-1199 U.S....

  18. Basins of Attraction for Chimera States

    DEFF Research Database (Denmark)

    Martens, Erik Andreas; Panaggio, Mark; Abrams, Daniel


    Chimera states---curious symmetry-broken states in systems of identical coupled oscillators---typically occur only for certain initial conditions. Here we analyze their basins of attraction in a simple system comprised of two populations. Using perturbative analysis and numerical simulation we...

  19. Stochastic basins of attraction for metastable states. (United States)

    Serdukova, Larissa; Zheng, Yayun; Duan, Jinqiao; Kurths, Jürgen


    Basin of attraction of a stable equilibrium point is an effective concept for stability analysis in deterministic systems; however, it does not contain information on the external perturbations that may affect it. Here we introduce the concept of stochastic basin of attraction (SBA) by incorporating a suitable probabilistic notion of basin. We define criteria for the size of the SBA based on the escape probability, which is one of the deterministic quantities that carry dynamical information and can be used to quantify dynamical behavior of the corresponding stochastic basin of attraction. SBA is an efficient tool to describe the metastable phenomena complementing the known exit time, escape probability, or relaxation time. Moreover, the geometric structure of SBA gives additional insight into the system's dynamical behavior, which is important for theoretical and practical reasons. This concept can be used not only in models with small noise intensity but also with noise whose amplitude is proportional or in general is a function of an order parameter. As an application of our main results, we analyze a three potential well system perturbed by two types of noise: Brownian motion and non-Gaussian α-stable Lévy motion. Our main conclusions are that the thermal fluctuations stabilize the metastable system with an asymmetric three-well potential but have the opposite effect for a symmetric one. For Lévy noise with larger jumps and lower jump frequencies ( α=0.5) metastability is enhanced for both symmetric and asymmetric potentials.

  20. Ferrobasalts from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.; Mukhopadhyay, R.; Popko, D.C.

    The occurrence of ferrobasalts recovered from the Central Indian Ocean Basin crust generated at the Southeast Indian Ridge during a phase of moderate to fast spreading accretion (approx 110-190 mm/yr, full rate) is reported. FeO (13-19%), and Ti...

  1. SEA of river basin management plans

    DEFF Research Database (Denmark)

    Larsen, Sanne Vammen; Kørnøv, Lone


    In, 2000 the European Parliament and the European Council passed the Water Framework Directive (WFD) to be implemented in all Member States. The consequence of the directive is that river basin management plans (RBMPs) shall be prepared which are legally subject to a strategic environmental...

  2. Alboran Basin, southern Spain - Part I: Geomorphology

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, A. [Secretaria General de Pesca Maritima, Corazon de Maria, 8, 28002 Madrid (Spain); Ballesteros, M.; Rivera, J.; Acosta, J. [Instituto Espanol de Oceanografia, Corazon de Maria, 8, 28002 Madrid (Spain); Montoya, I. [Universidad Juan Carlos I, Campus de Mostoles, Madrid (Spain); Uchupi, E. [Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States)


    Bathymetric, 3D relief and shaded relief maps created from multibeam echo-sounding data image the morphology of the Alboran Basin, a structural low along the east-west-trending Eurasian-African plates boundary. Topographic features in the basin are the consequence of volcanism associated with Miocene rifting, rift and post-rift sedimentation, and recent faulting resulting from the convergence of the African-Eurasian plates. Pleistiocene glacially induced regressions/transgressions when the sea level dropped to about 150 m below its present level gas seeps and bottom currents. Recent faulting and the Pleistocene transgressions/regressions led to mass-wasting, formation of turbidity currents and canyon erosion on the basin's slopes. Recent fault traces at the base of the northern basin slope have also served as passageways for thermogenic methane, the oxidation of which by bacteria led to the formation of carbonate mounds along the fault intercepts on the sea floor. Expulsion of thermogenic or biogenic gas has led to the formation of pockmarks; erosion by bottom currents has resulted in the formation of moats around seamounts and erosion of the seafloor of the Alboran Ridge and kept the southern edge of the 36 10'N high sediment free. (author)

  3. Water and Security in the Jordan Basin (United States)


    political, and diplomatic strengths. For this reason alone, it serves as an excellent tool for working on the problems of the Jordan basin. 561...and Brdens:L R pr cm the West Bank and Gaza rip Ecnmi since 1967. New York: Carnegie Endowment, 1977. Weinbaum, Marvin G. F Devopment and Politing in

  4. Evidence for Himalayanremagnetization in TarimBasin

    Institute of Scientific and Technical Information of China (English)


    Himalayan remagnetization in the Tarim Basin was found to be widespread in Paleozoic, Mesozoic and Cenozoic rocks. Rock magnetism was performed to study the magnetic carriers. The authors believe that tectonic fluid in the Himalayan stage caused the rock remagnetization. The framboidal pyrites in bitumen and hydrocarbon-rich rocks may transform to framboidal magnetite in the later alkali environment, which leads to remagnetization.

  5. KE Basin underwater visual fuel survey

    Energy Technology Data Exchange (ETDEWEB)

    Pitner, A.L.


    Results of an underwater video fuel survey in KE Basin using a high resolution camera system are presented. Quantitative and qualitative information on fuel degradation are given, and estimates of the total fraction of ruptured fuel elements are provided. Representative photographic illustrations showing the range of fuel conditions observed in the survey are included.

  6. Integrated high-resolution stratigraphy: Relative contributions of tectonics, eustasy and climate on basin evolution (Vienna Basin, Austria)

    NARCIS (Netherlands)

    Paulissen, W.E.


    Sedimentary basins form in a range of large-scale tectonic settings involving extensional, compressional or lateral movements. The dynamics of the basin infill are controlled by driving mechanisms such as tectonics, climate and eustatic control. The created accommodation space in the basin is filled

  7. Evolution of Mesozoic Volcanic Basins and Red Basins in the Gan-Hang Tectonic-Volcanic Metallogenic Belt

    Institute of Scientific and Technical Information of China (English)


    This paper mainly proposes six major regional geological events in the active continental-margin mantle uplift zone and discusses the oscillation nature of the evolution of Mesozoic volcanic basins and red basins, origin of erosion in the late stage of red basins and mechanism of volcanism.

  8. Classification of Complex Reservoirs in Superimposed Basins of Western China

    Institute of Scientific and Technical Information of China (English)

    PANG Xiongqi; ZHOU Xinyuan; LIN Changsong; HUO Zhipeng; LUO Xiaorong; PANG Hong


    Many of the sedimentary basins in western China were formed through the superposition and compounding of at least two previously developed sedimentary basins and in general they can be termed as complex superimposed basins.The distinct differences between these basins and monotype basins are their discontinuous stratigraphic sedimentation,stratigraphic structure and stratigraphic stress-strain action over geological history.Based on the correlation of chronological age on structural sections,superimposed basins can be divided into five types in this study:(1)continuous sedimentation type superimposed basins,(2)middle and late stratigraphic superimposed basins,(3)early and late stratigraphic superimposed basins,(4)early and middle stratigraphic superimposed basins,and(5)long-term exposed superimposed basins.Multiple source-reservoir-caprock assemblages have developed in such basins.In addition,multi-stage hydrocarbon generation and expulsion,multiple sources,polycyclic hydrocarbon accumulation and multiple-type hydrocarbon reservoirs adjustment,reformation and destruction have occurred in these basins.The complex reservoirs that have been discovered widely in the superimposed basins to date have remarkably different geologic features from primary reservoirs,and the root causes of this are folding,denudation and the fracture effect caused by multiphase tectonic events in the superimposed basins as well as associated seepage,diffusion,spilling,oxidation,degradation and cracking.Based on their genesis characteristics,complex reservoirs are divided into five categories:(1)primary reservoirs,(2)trap adjustment type reservoirs,(3)component variant reservoirs,(4)phase conversion type reservoirs and(5)scale-reformed reservoirs.


    Directory of Open Access Journals (Sweden)



    Full Text Available The Jurassic history of the Pieniny/Outer Carpathian basins reflects the evolution of the Circum-Tethyan area, especially its Alpine Tethys part. The Alpine Tethys that is Ligurian, Penninic Oceans and Pieniny/Magura Basin constitute the extension of the Central Atlantic system. The synrift stage lasted in the Pieniny/Magura Basin from late Early Jurassic to Tithonian (the Magura Unit constitutes the southernmost part of the Outer Flysch Carpathians. The Pieniny rift opened during Pliensbachian – Aalenian. The central Atlantic and Alpine Tethys went into a drifting stage during the Middle Jurassic. The Late Jurassic (Oxfordian-Kimmeridgian history of the Pieniny/Magura Basin reflects strongest facial differentiation within sedimentary basin where mixed siliceous-carbonate sedimentation took place. Greatest deepening effect is indicated by widespread Oxfordian radiolarites, which occur in the all basinal successions, whereas the shallowest zone is completely devoid of siliceous intercalations at that time (sedimentation from Ammonitico Rosso facies up to coral reef limestone. The southern part of the North European Platform, north from the Pieniny/Magura realm, started to be rifted during Late Jurassic time and Silesian Basin in the Outer Western Carpathians and Sinaia Basin in the Eastern Carpathians, with black, mainly redeposited marls have been created. The outer sub-basins were differentiated during the latest (Hauterivian-Barremian phase of basinal development. The connection of Silesian Basin with Sinaia and Southern Carpathian Severin areas suggests the NW-SE direction of the basinal axis while the orientation of the Pieniny Klippen Belt/Magura Basin was SW-NE so, two Outer Carpathian perpendicular directions are possible within the basins. Major reorganization happened during the Tithonian-Berriasian time. It was reflected by both paleoceanographical and paleoclimatical changes. The Neo-Cimmerian tectonic events as well as main phase

  10. Modeling Nitrogen Losses under Rapid Infiltration Basins (United States)

    Akhavan, M.; Imhoff, P. T.; Andres, A. S.; Finsterle, S.


    Rapid Infiltration Basin System (RIBS) is one of the major land treatment techniques used for wastewater treatment and reuse of recovered treated wastewater. In this system, wastewater that is treated using primary, secondary, or advanced treatment techniques is applied at high rates to shallow basins constructed in permeable deposits of soil or sand, with further treatment occurring in soil and the vadose zone before the water recharges groundwater. Because the influent wastewater is usually enriched in nitrogen (N) compounds, there is particular concern that RIBS may contaminant groundwater or nearby surface waters if not designed and operated properly. In most of the new sequenced batch reactor (SBR) wastewater treatment plants, N is found in the form of nitrate in the discharged wastewater, so denitrification (DNF) is the main reaction in N removal. The absence of molecular oxygen is one of the required conditions for DNF. During RIBS operation, application of wastewater is cyclic and typically consists of a flooding period followed by days or weeks of drying. Key operational parameters include the ratio of wetting to drying time and the hydraulic loading rate, which affect water saturation and air content in the vadose zone and as a result have an impact on DNF. Wastewater is typically distributed at a limited number of discharge points in RIBS and basins are not usually completely flooded which result in non-homogeneous distribution of wastewater and unusual surface water flow patterns. For this reason, we couple overland flow within RIBS with subsurface flow to investigate the influence of non-uniform application of wastewater on DNF. No modeling effort has been done for understanding this aspect of RIBS performance previously. TOUGH2/ iTOUGH2, a general-purpose numerical simulation program for multi-phase fluid flow in porous media, is used for modeling fluid movement. Water saturation is used as a surrogate parameter to evaluate oxygen limitations in the

  11. Effectiveness of Integrated Device of Ultrafiltration Process for Treatment of High Algae-Laden Raw Water from Minjiang River%超滤一体化装置处理闽江高含藻原水的效果

    Institute of Scientific and Technical Information of China (English)

    林茜; 范功端; 魏忠庆; 黄功洛; 苏昭越; 陈丽茹; 林茹晶


    考察了集混凝—斜管沉淀—超滤于一体的装置在高藻水期对闽江水的净水效果。结果表明超滤一体化装置出水浊度小于0.1 NTU,浊度去除率达到99%以上;出水CODMn均值为1.40 mg/L,出水UV254为0.024 cm-1,CODMn和UV254去除率分别为57.3%和50.1%;出水细菌含量低于《生活饮用水标准》( GB 5749—2006)的限值,细菌去除率大于99%。超滤组合工艺对藻类处理效果优于水厂工艺,藻类总去除率为99.3%。当膜通量下降时,缩短过滤时间、延长反冲洗时间可以使膜通量恢复;当超滤膜出现不可逆污染时,通过CIP清洗恢复膜过滤性能。在高藻水期,水温对膜通量和TMP影响较小,在保证出水水质的前提下,较大的膜通量运行更节能。%An integrated device of ultrafiltration in combination with coagulation and sedimentation was built to treat Minjiang river water, and the treatment effect during high algae laden period was investigated.The results show that turbidity of effluent is less than 0.1 NTU, and removal rate of turbidity is 99%.CODMn and UV254 of effluent are 1.40 mg/L and 0.024 cm-1 , respectively, and the corresponding removal rates are 57.3%and 50.1%.The number of bacteria of effluent is less than the limit value from Drinking Water Standards (GB 5749—2006), and removal rate is higher than 99%.The removal effect of algae with combined process is better than that with traditional process in water plant at present, the removal rate of algae is 99.3%.Decreasing the filtering time and prolonging the back flushing time is able to restore the membrane flux.If there is irreversible pollution on ultrafiltration membrane, cleaning in place ( CIP) is effective restoring the membrane filtration performance.In the high algae-laden period, water temperature has no significant influence on membrane flux and trans-membrane pressure ( TMP) , and therefore using larger membrane flux

  12. Magmatism in rifting and basin formation (United States)

    Thybo, H.


    Whether heating and magmatism cause rifting or rifting processes cause magmatic activity is highly debated. The stretching factor in rift zones can be estimated as the relation between the initial and the final crustal thickness provided that the magmatic addition to the crust is insignificant. Recent research demonstrates substantial magmatic intrusion into the crust in the form of sill like structures in the lowest crust in the presently active Kenya and Baikal rift zones and the DonBas palaeo-rift zone in Ukraine. This result may be surprising as the Kenya Rift is associated with large amounts of volcanic products, whereas the Baikal Rift shows very little volcanism. Identification of large amounts of magmatic intrusion into the crust has strong implications for estimation of stretching factor, which in the case of Baikal Rift Zone is around 1.7 but direct estimation gives a value of 1.3-1.4 if the magmatic addition is not taken into account. This may indicate that much more stretching has taken place on rift systems than hitherto believed. Wide sedimentary basins may form around aborted rifts due to loading of the lithosphere by sedimentary and volcanic in-fill of the rift. This type of subsidence will create wide basins without faulting. The Norwegian- Danish basin in the North Sea area also has subsided gradually during the Triassic without faulting, but only few rift structures have been identified below the Triassic sequences. We have identified several mafic intrusions in the form of large batholiths, typically more than 100 km long, 20-40 km wide and 20 km thick. The associated heating would have lifted the surface by about 2 km, which may have been eroded before cooling. The subsequent contraction due to solidification and cooling would create subsidence in a geometry similar to basins that developed by loading. These new aspects of magmatism will be discussed with regard to rifting and basin formation.

  13. Modeling Fluid Flow in Faulted Basins

    Directory of Open Access Journals (Sweden)

    Faille I.


    Full Text Available This paper presents a basin simulator designed to better take faults into account, either as conduits or as barriers to fluid flow. It computes hydrocarbon generation, fluid flow and heat transfer on the 4D (space and time geometry obtained by 3D volume restoration. Contrary to classical basin simulators, this calculator does not require a structured mesh based on vertical pillars nor a multi-block structure associated to the fault network. The mesh follows the sediments during the evolution of the basin. It deforms continuously with respect to time to account for sedimentation, erosion, compaction and kinematic displacements. The simulation domain is structured in layers, in order to handle properly the corresponding heterogeneities and to follow the sedimentation processes (thickening of the layers. In each layer, the mesh is unstructured: it may include several types of cells such as tetrahedra, hexahedra, pyramid, prism, etc. However, a mesh composed mainly of hexahedra is preferred as they are well suited to the layered structure of the basin. Faults are handled as internal boundaries across which the mesh is non-matching. Different models are proposed for fault behavior such as impervious fault, flow across fault or conductive fault. The calculator is based on a cell centered Finite Volume discretisation, which ensures conservation of physical quantities (mass of fluid, heat at a discrete level and which accounts properly for heterogeneities. The numerical scheme handles the non matching meshes and guaranties appropriate connection of cells across faults. Results on a synthetic basin demonstrate the capabilities of this new simulator.

  14. Analysis of K west basin canister gas

    Energy Technology Data Exchange (ETDEWEB)

    Trimble, D.J., Fluor Daniel Hanford


    Gas and Liquid samples have been collected from a selection of the approximately 3,820 spent fuel storage canisters in the K West Basin. The samples were taken to characterize the contents of the gas and water in the canisters providing source term information for two subprojects of the Spent Nuclear Fuel Project (SNFP) (Fulton 1994): the K Basins Integrated Water Treatment System Subproject (Ball 1996) and the K Basins Fuel Retrieval System Subproject (Waymire 1996). The barrels of ten canisters were sampled for gas and liquid in 1995, and 50 canisters were sampled in a second campaign in 1996. The analysis results from the first campaign have been reported (Trimble 1995a, 1995b, 1996a, 1996b). The analysis results from the second campaign liquid samples have been documented (Trimble and Welsh 1997; Trimble 1997). This report documents the results for the gas samples from the second campaign and evaluates all gas data in terms of expected releases when opening the canisters for SNFP activities. The fuel storage canisters consist of two closed and sealed barrels, each with a gas trap. The barrels are attached at a trunion to make a canister, but are otherwise independent (Figure 1). Each barrel contains up to seven N Reactor fuel element assemblies. A gas space of nitrogen was established in the top 2.2 to 2.5 inches (5.6 to 6.4 cm) of each barrel. Many of the fuel elements were damaged allowing the metallic uranium fuel to be corroded by the canister water. The corrosion releases fission products and generates hydrogen gas. The released gas mixes with the gas-space gas and excess gas passes through the gas trap into the basin water. The canister design does not allow canister water to be exchanged with basin water.

  15. Water Temperature Controls in Arctic Basins (United States)

    Neilson, B. T.; King, T.; Schmadel, N. M.; Heavilin, J.; Overbeck, L. D.; Kane, D. L.


    Understanding the dynamics of heat transfer mechanisms in arctic rivers is critical for forecasting the effects of climate change on river temperatures. Building on the collection of key data and a dynamic river temperature model that accounts for heat fluxes found important in temperate climates, we were able to identify portions of an arctic basin and hydrologic conditions for which heat flux dynamics differ from those found in temperate systems. During the open water season, similarities in heat flux influences include dominant shortwave radiation, greater surface exchanges than bed exchanges and greater influences of lateral inflows in the lower order portions of the basin. Differing from temperate systems, the heat flux contribution of net longwave radiation is consistently negative and both latent heat and bed friction are negligible. Despite these differences, accounting for the bulk lateral inflows from the basin resulted in accurate predictions during higher flows. Under lower flow conditions, however, lateral inflows were limited and resulting temperature predictions were poor. Work in a temperate system demonstrated that spatial variability in hydraulics influencing stream residence times are necessary for accurate river temperature predictions. Because heat fluxes at the air-water interface become increasingly dominant at low flows and these fluxes are sensitive to parameters representing the water surface area to volume ratio, similar to temperate systems, we expect that high-resolution representations of stream geometry and hydraulics are important both for accurate flux and residence time estimates. Furthermore, given the highly dynamic nature of flows in arctic basins, we anticipate that detailed information regarding spatially variable hydraulic characteristics (e.g., channel width, depth, and velocity) is critical for accurate predictions in low arctic rivers through a large range of flow conditions. Upon identifying key processes controlling

  16. Okanogan Basin Spring Spawner Report for 2007.

    Energy Technology Data Exchange (ETDEWEB)

    Colville Tribes, Department of Fish & Wildlife


    The Okanogan Basin Monitoring and Evaluation Program collected data related to spring spawning anadromous salmonid stocks across the entire Okanogan River basin. Data were collected using redd surveys, traps, underwater video, and PIT-tag technology then summarized and analyzed using simple estimate models. From these efforts we estimated that 1,266 summer steelhead spawned in the Okanogan River basin and constructed 552 redds;152 of these fish where of natural origin. Of these, 121 summer steelhead, including 29 of natural origin, created an estimated 70 redds in the Canadian portion of the Okanagan basin. We estimated summer steelhead spawner escapement into each sub-watershed along with the number from natural origin and the number and density of redds. We documented redd desiccation in Loup Loup Creek, habitat utilization in Salmon Creek as a result of a new water lease program, and 10 spring Chinook returning to Omak Creek. High water through most of the redd survey period resulted in development of new modeling techniques and allowed us to survey additional tributaries including the observation of summer steelhead spawning in Wanacut Creek. These 2007 data provide additional support that redd surveys conducted within the United States are well founded and provide essential information for tracking the recovery of listed summer steelhead. Conversely, redd surveys do not appear to be the best approach for enumerating steelhead spawners or there distribution within Canada. We also identified that spawning distributions within the Okanogan River basin vary widely and stocking location may play an over riding roll in this variability.

  17. Petroleum systems of the Taoudeni Basin,West Africa

    Institute of Scientific and Technical Information of China (English)

    Huang Zhilong; Zhao Baoshun; Jiang Qingchun; Wang Songpo; Liu Bo


    The Taoudeni Basin is a typical steady intracratonic basin. Based on the distribution of effective source rocks in the Taoudeni Basin, combined with the structure characteristics of the basin and the distribution characteristics of reservoir beds, two petroleum systems are recognized in the basin:the infra-Cambrian petroleum system and the Silurian petroleum system. Structural uplift and timing of petroleum generation controlled the timing of petroleum charging and preservation of hydrocarbon accumulations. Maturity, evolution history, and distribution of effective source rocks controlled hydrocarbon richness. The geological key factors and geological processes controlled the type of hydrocarbon accumulations.

  18. 作业场所风险影响因素分析及评估模型研究%Analysis of risks-laden factors at working places and a renovated evaluation model

    Institute of Scientific and Technical Information of China (English)

    田彦清; 杨振宏; 李华; 尚旭光


    restraints, safety technology, legal regulation and social economic benefits, etc. A careful summary on the risks-laden factors of the working places has made us clear that 36 factors of such nature are to be taken account of with our topic. Professionally and theoretically speaking, it is convenient to categorize the paper the 36 factors into 5 hierarchal levels. Furthermore, analyzing the relationship and structure of all the influential factors enables us to obtain the direct surface, middle-level indirect and deep-level fundamentally affecting factors, which include the company or enterprise culture, the safety evaluation, the government-supervision mechanism, the social supervision, the legal standards and the regulatory enforcement of the authoritative institutions. Next, based on the thorough-going systematic investigation over a sample workplace of some steel-rolling company, we have applied the above-said direct surface-level affecting factors to the risk assessment of the occupational hazards of the sample place. With the help of the computer expertise database specifically prepared, we have compared the degrees of all the influential factors with the referential index of assessment goals. The assessment results indicate that the closer the association between the assessment goals and the assessment levels, the more closely interconnected they would him to be. And, finally, the assessment results prove that the occupational hazards laden in the above mentioned steel rolling company turns to be of the second level, that is, of the general hazard-laden degree, within the controllable normal managing situation. Hence, the present research is valuable and provides an effective way for the accident-prevention and controlling of the occupational hazards of such conditions.

  19. Distribution, Statistics, and Resurfacing of Large Impact Basins on Mercury (United States)

    Fassett, Caleb I.; Head, James W.; Baker, David M. H.; Chapman, Clark R.; Murchie, Scott L.; Neumann, Gregory A.; Oberst, Juergen; Prockter, Louise M.; Smith, David E.; Solomon, Sean C.; Strom, Robert G.; Xiao, Zhiyong; Zuber, Maria T.


    The distribution and geological history of large impact basins (diameter D greater than or equal to 300 km) on Mercury is important to understanding the planet's stratigraphy and surface evolution. It is also informative to compare the density of impact basins on Mercury with that of the Moon to understand similarities and differences in their impact crater and basin populations [1, 2]. A variety of impact basins were proposed on the basis of geological mapping with Mariner 10 data [e.g. 3]. This basin population can now be re-assessed and extended to the full planet, using data from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. Note that small-to- medium-sized peak-ring basins on Mercury are being examined separately [4, 5]; only the three largest peak-ring basins on Mercury overlap with the size range we consider here. In this study, we (1) re-examine the large basins suggested on the basis of Mariner 10 data, (2) suggest additional basins from MESSENGER's global coverage of Mercury, (3) assess the size-frequency distribution of mercurian basins on the basis of these global observations and compare it to the Moon, and (4) analyze the implications of these observations for the modification history of basins on Mercury.

  20. Oil shale and nahcolite resources of the Piceance Basin, Colorado (United States)



    This report presents an in-place assessment of the oil shale and nahcolite resources of the Green River Formation in the Piceance Basin of western Colorado. The Piceance Basin is one of three large structural and sedimentary basins that contain vast amounts of oil shale resources in the Green River Formation of Eocene age. The other two basins, the Uinta Basin of eastern Utah and westernmost Colorado, and the Greater Green River Basin of southwest Wyoming, northwestern Colorado, and northeastern Utah also contain large resources of oil shale in the Green River Formation, and these two basins will be assessed separately. Estimated in-place oil is about 1.5 trillion barrels, based on Fischer a ssay results from boreholes drilled to evaluate oil shale, making it the largest oil shale deposit in the world. The estimated in-place nahcolite resource is about 43.3 billion short tons.