High Energy Density Physics Research Papers (original) (raw)

We calculate the incoherent resonant and non-resonant scattering production of sterile neutrinos in the early universe. We find ranges of sterile neutrino masses, vacuum mixing angles, and initial lepton numbers which allow these species to constitute viable hot, warm, and cold dark matter (HDM, WDM, CDM) candidates which meet observational constraints. The constraints considered here include energy loss in core collapse supernovae, energy density limits at big bang nucleosynthesis, and those stemming from sterile neutrino decay: limits from observed cosmic microwave background anisotropies, diffuse extragalactic background radiation, and Li-6/D overproduction. Our calculations explicitly include matter effects, both effective mixing angle suppression and enhancement (MSW resonance), as well as quantum damping. We for the first time properly include all finite temperature effects, dilution resulting from the annihilation or disappearance of relativistic degrees of freedom, and the scattering-rate-enhancing effects of particle-antiparticle pairs (muons, tauons, quarks) at high temperature in the early universe.

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- Quantum Physics, Dark Matter, High Energy Density Physics, Early Universe

It is extraordinary that a number of observations indicate that we live in a spatially flat, low matter density Universe, which is currently undergoing a period of accelerating expansion. The effort to explain this current state has focused attention on cosmological models in which the dominant component of the cosmic energy density has negative pressure, with an equation of state w ≥ −1. Remarking that most observations are consistent with models right up to the w = −1 or cosmological constant (Λ) limit, it is natural to ask what lies on the other side, at w < −1. In this regard, we construct a toy model of a "phantom" energy component which possesses an equation of state w < −1. Such a component is found to be compatible with most classical tests of cosmology based on current data, including the recent type 1a SNe data as well as the cosmic microwave background anisotropy and mass power spectrum. If the future observations continue to allow w < −1, then barring unanticipated systematic effects, the dominant component of the cosmic energy density may be stranger than anything expected.

Fast ignition requires a precise knowledge of fast electron propagation in a dense hydrogen plasma. In this context, a dedicated HiPER (High Power laser Energy Research) experiment was performed on the VULCAN laser facility where the propagation of relativistic electron beams through cylindrically compressed plastic targets was studied. In this paper, we characterize the plasma parameters such as temperature and density during the compression of cylindrical polyimide shells filled with CH foams at three different initial densities. X-ray and proton radiography were used to measure the cylinder radius at different stages of the compression. By comparing both diagnostics results with 2D hydrodynamic simulations, we could infer densities from 2 to 11 g=cm 3 and temperatures from 30 to 120 eV at maximum compression at the center of targets. According to the initial foam density, kinetic, coupled (sometimes degenerated) plasmas were obtained. The temporal and spatial evolution of the resulting areal densities and electrical conductivities allow for testing electron transport in a wide range of configurations. V

In this paper, a dielectric barrier discharge operating in nitrogen at atmospheric pressure has been used to improve the surface hydrophilic property of polypropylene (PP) non-woven fabric. The changes in the hydrophilic property of the modified PP samples are investigated by the contact angle measurements and the variation of water contact angle is obtained as a function of the energy density; micrographs of the PP before and after plasma treatment are observed by scanning electron microscopy (SEM) and the chemical composition of the PP surface before and after plasma treatment is also analyzed by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results show that the surface hydrophilic property of the PP samples is greatly improved with plasma treatment for a few seconds, as evidenced by the fact that the contact angle of the treated PP samples significantly decreases after plasma treatment. The analysis of SEM shows that the surface roughness of the treated PP samples increases due to bonding and etching in plasma processing. The analyses of FTIR and the C1s peak in the high-resolution XPS indicate that oxygen-containing and nitrogen-containing polar functional groups are introduced into PP surface in plasma processing. It can be concluded that the surface hydrophilic property of the modified PP samples has been obviously improved due to the introduction of oxygen-containing and nitrogen-containing polar groups and the increase of the surface roughness on the PP surface.

This work examines the finite temperature properties of the CPT-even and parity-odd electrodynamics of the standard model extension. We start from the partition function written into the functional integral formalism in Ref. . After specializing the Lorentz-violating tensor Wανρϕ for the nonbirefringent and parity-odd coefficients, the partition function is explicitly carry out, showing that it is a power of the Maxwell's partition function. Also, it is observed that the LIV coefficients induce an anisotropy in the black body angular energy density distribution. The Planck's radiation law retains its usual frequency dependence and the Stefan-Boltzmann law keeps the same form, except for a global proportionality constant.

This study describes the use of electrodeposited nanostructured hybrid nickel–cobalt hexacyanoferrate in electrochemical supercapacitors. Herein, various compositions of nickel and cobalt hexacyanoferrates (Ni/CoHCNFe) nanostructures are electrodeposited on an inexpensive stainless steel substrate using cyclic voltammetric (CV) method. The morphology of the electrodeposited nanostructures is studied using scanning electron microscopy, while their electrochemical characterizations are investigated using CV, galvanostatic charge and discharge and electrochemical impedance spectroscopy. The results show that the nanostructures of hybrid metal cyanoferrate, shows a much higher capacitance (765 F g−1) than those obtained with just nickel hexacyanoferrate (379 F g−1) or cobalt hexacyanoferrate (277 F g−1). Electrochemical impedance spectroscopy results confirm the favorable capacitive behavior of the electrodeposited materials. The columbic efficiency is approximately 95% based on the charge and discharge experiments. Long cycle-life and excellent stability of the nanostructured materials are also demonstrated during 1000 cycles.► Nanostructured hybrid nickel–cobalt hexacyanoferrate is used in supercapacitors. ► A high capacitance (765 F g−1) is obtained at a specific current of 0.2 A g−1. ► Long cycle-life and excellent stability are demonstrated during 1000 cycles.

The polytropic gas model is investigated as an interacting dark energy scenario. In this model the evolution of cosmological parameters such as the EoS parameter w Λ , energy density Ω Λ and deceleration parameter q are investigated. These parameters are dependent on the parameters of the model. We show that, depending on the parameter of model, the interacting polytropic gas can behave as a quintessence or phantom dark energy. The singularity of this model is also discussed. Eventually, we establish the correspondence between interacting polytropic gas model with tachyon, K-essence and dilaton scalar fields. The potential and the dynamics of these scalar field models are reconstructed according to the evolution of interacting polytropic gas. * Recent cosmological observations obtained by SNe Ia [1], WMAP [2], SDSS [3] and X-ray [4] experiments reveal that our universe expands under an accelerated expansion. In the framework of standard Freidmann-Robertson-Walker (FRW) cosmology, a missing energy component with negative pressure dubbed dark energy (DE) is responsible for this expansion. The nature of DE is still unknown and scientists believe that the problem of DE is a major puzzle of modern cosmology. Up to now, many theoretical models have been investigated to interpret the behavior of DE. The time-independent cosmological constant, Λ, with EoS parameter w = −1 is the earliest and simplest candidate of DE. The cosmological constant suffers from two well known difficulties namely "fine-tuning" and "cosmic coincidence" problems. The alternative candidates for DE problem are the dynamical dark energy scenario with time varying EoS parameter ,w. According to some analysis on the SNe Ia observational data, it has been shown that the time-varying DE models give a better fit compare with a cosmological constant [5]. There are two different categories for dynamical DE scenario: (i ) The scalar fields including quintessence [6], phantom [7], quintom [8], K-essence [9], tachyon [10], dilaton [11] and so forth. (ii ) The interacting DE models including Chaplygin gas models [12], braneworld models [13], holographic [14] and agegraphic [15] models. The holographic DE model is constructed in the light of holographic principle of quantum gravity [16] and the agegraphic model is constructed based on the uncertainty relation of quantum mechanics together with the gravitational effect in general relativity [17]. The interaction between DE and dark matter is supported by recent observations prepared by the Abell Cluster A586 [18]. However the strength of this interaction is not clearly identified [19]. Also, recent astronomical data supported that our universe is not a perfectly flat and has a small positive curvature [20]. Recently, by using the polytropic gas model, the interaction between DE and dark matter is investigated [21]. Karami, et al. obtained the phantom behavior of interacting polytropic gas model [21]. Also, karami, et al. reconstructed the f (T )-gravity from the polytropic gas DE model [23]

First, the nuclear proximity potential, obtained by using the semiclassical extended Thomas Fermi (ETF) approach in Skyrme energy density formalism (SEDF), is shown to give more realistic barriers in frozen density approximation, as compared to the sudden approximation. Then, taking advantage of the fact that, in ETF method, different Skyrme forces give different barriers (height, position and curvature), we use thesummed extended-Wong model of Gupta and collaborators (2009) [1] under frozen densities approximation for calculating the cross-sections, where the Skyrme force is chosen with proper barrier characteristics, notrequiring additional "barrier modification" effects (lowering or narrowing, etc.), for a best fit to data at subbarrier energies. The method is applied to capture cross-section data from 48 Ca + 238 U, 244 Pu, and 248 Cm reactions and to fusion-evaporation cross-sections from 58 Ni + 58 Ni, 64 Ni + 64 Ni, and 64 Ni + 100 Mo reactions, with effects of deformations and orientations of nuclei included, wherever required. Interestingly, whereas the capture cross-sections in Ca-induced reactions could be fitted to any force, such as SIII, SV and GSkI, by allowing a small change of couple of units in deduced max -values at below-barrier energies, the near-barrier data point of 48 Ca + 248 Cm reaction could not be fitted to max -values deduced for belowbarrier energies, calling for a check of data. On the other hand, the fusion-evaporation cross-sections in Ni-induced reactions at sub-barrier energies required different Skyrme forces, representing "modifications of the barrier", for the best fit to data at all incident center-of-mass energies E c.m. 's, displaying a kind of fusion hindrance at sub-barrier energies. This barrier modification effect is taken into care here by using different Skyrme forces for reactions belonging to different regions of the periodic table. Note that more than one Skyrme force (with identical barrier characteristics) could equally well fit the same data.

- by Manoj Sharma
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- High Energy Density Physics, Cross Section, Center of Mass

The new mathematical model to estimate volumetric and gravimetric energy densities of the rechargeable NiMH batteries has been proposed. Application of the new prospective Mg 0.80 Sc 0.20 (1740 mAh/g) hydride forming material for MH electrode has been studied with the help of that model. It was shown that application of the new Mg 0.80 Sc 0.20 material gives 58 % advance in gravimetric energy density (Wh/kg) for AA-size battery those expected capacity reaches 3045 mAh. For the battery having the same weight as normal AA-size battery higher gains have been achieved, namely, 5 % increase in volumetric energy density and 80 % in gravimetric. Thus prospective NiMH battery may compete with majority of the currently available lithium-ion batteries. The new binary (e.g. Mg-Ti) and ternary (e.g. Mg-Ti-Al) alloys having the same capacity as

- by Alexander Ledovskikh
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- Data Analysis, High Energy Density Physics, Lithium Ion Battery, Nickel

Bio-oil and bio-char were produced from corn cobs and corn stover (stalks, leaves and husks) by fast pyrolysis using a pilot scale fluidized bed reactor. Yields of 60% (mass/mass) bio-oil (high heating values are w20 MJ kg À1 , and densities >1.0 Mg m À3) were realized from both corn cobs and from corn stover. The high energy density of bio-oil, w20-32 times on a per unit volume basis over the raw corn residues, offers potentially significant savings in transportation costs particularly for a distributed ''farm scale'' bio-refinery system. Biochar yield was 18.9% and 17.0% (mass/mass) from corn cobs and corn stover, respectively. Deploying the bio-char co-product, which contains most of the nutrient minerals from the corn residues, as well as a significant amount of carbon, to the land can enhance soil quality, sequester carbon, and alleviate environmental problems associated with removal of crop residues from fields.

- by isabel Lima
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- Engineering, Environmental Science, Technology, Production

Fick’s model together with Arrhenius relationship were successfully used to evaluate water absorption of chickpea during soaking at a temperature range of 20–97 °C with 25 kHz 100 W, 40 kHz 100 W and 25 kHz 300 W ultrasound treatments. Use of ultrasound, increase in ultrasound power and soaking temperature significantly (P < 0.05) increased the water diffusion coefficient (Deff) of chickpea during soaking. Average gelatinization temperature of chickpea was found as 61.47 °C. Activation energy (Ea) values of chickpea for below and above gelatinization temperature were found to be 28.69 and 9.34 kJ mol−1, respectively. Ultrasound treatments significantly decreased the soaking time of chickpea.

- by Mehmet Oner
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- Food Engineering, Ultrasound, High Energy Density Physics, Activation Energy

The energy and time scales during the inflationary stage of the universe calls for an out of equilibrium quantum field treatment. Moreover, the high energy densities involved (∼ 1/g ∼ 10 12 ) make necessary the use of non-perturbative approaches as the large N and Hartree methods. We start these lectures by introducing the such non-perturbative out of equilibrium methods in cosmological universes. We discuss the renormalization procedure and the choice of initial conditions. We then study with these methods the non-linear dynamics of quantum fields in matter and radiation dominated FRW and de Sitter universes. For a variety of initial conditions, we compute the evolution of the inflaton, its quantum fluctuations and the equation of state. We investigate the phenomenon of explosive particle production due to spinodal instabilities and parametric amplification in FRW and de Sitter universes with and without symmetry breaking. We find that the particle production is somewhat sensitive to the expansion of the universe. In the large N limit for symmetry breaking scenarios, we determine generic late time fields behavior for any flat FRW and de Sitter cosmology. We find that quantum fluctuations damp in FRW as the square of the scale factor while the order parameter approaches a minimum of the potential at the same rate. We present a complete and numerically accessible renormalization scheme for the equation of motion and the energy momentum tensor in flat cosmologies. In this scheme the renormalization constants are independent of time and of the initial conditions. Furthermore, we consider an O(N ) inflaton model coupled self-consistently to gravity in the semiclassical approximation, where the field is subject to 'new inflation' type initial conditions. We study the dynamics self-consistently and non-perturbatively with non-equilibrium field theory methods in the large N limit. We find that spinodal instabilities drive the growth of non-perturbatively large quantum fluctuations which shut off the inflationary growth of the scale factor. We find that a very specific combination of these large fluctuations plus the inflaton zero mode assemble into a new effective field. This new field behaves classically and it is the object 1 which actually rolls down. We show how this reinterpretation qualitatively saves the standard picture of how metric perturbations are generated during inflation and that the spinodal growth of fluctuations dominates the time dependence of the Bardeen variable for superhorizon modes during inflation. We compute the amplitude and index for the spectrum of scalar density and tensor perturbations and argue that in all models of this type the spinodal instabilities are responsible for a 'red' spectrum of primordial scalar density perturbations. The decoherence aspects and the quantum to classical transition through inflation are studied in detail by following the full evolution of the density matrix.

- by S. Prem Kumar and +1
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- Nonlinear dynamics, High Energy Density Physics, Spectrum, Symmetry Breaking

Multi-proxy approach was used to reconstruct the environmental conditions of remote lakes in the High Tatra Mountains (Slovakia) over the past few centuries (approximately 500-1000 years). Short sediment cores (*30 cm) taken from three morphologically similar glacial lakes distributed along altitudinal gradient (subalpine to alpine conditions) were analysed for organic matter content (LOI), diatoms and chironomids. Both descriptive and correlative approaches were used for analysing stratigraphical data. Predictive canonical correspondence analysis and co-correspondence analysis were applied to directly relate physical and biological proxies to each other. The relationship between LOI and biotic proxies was inconsistent across groups and lakes. Concordant patterns in diatom and chironomid composition were found in two non-acidified lakes. Common trends in those assemblages indicated major past environmental events such as the Little Ice Age, air pollution and lake acidification. In contrast, no relationship between the composition of diatom and chironomid assemblages was found in the formerly acidified lake, suggesting different responses of assemblages to acidification. While chironomids showed shifts that are attributable to recovery, diatoms assemblage remained relatively stable throughout the uppermost layers of the sediment record. On the other hand, climatic-driven changes in assemblages detected in the deeper layers were more pronounced in diatoms than in chironomids.

- by Gregory Fahy
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- Management, Ecological Engineering, Optical Engineering, Biochemistry

Electrochemical capacitors have recently been attracting significant interest because they can instantaneously provide a higher power density than batteries and a higher energy density than conventional dielectric capacitors. Such outstanding properties make them excellent candidates for hybrid electric vehicles, computers, mobile electric devices, and other applications. [1,2] Generally, an electrochemical capacitor may be operated based on the electrochemical double-layer capacitance (EDLC) formed along an electrode/electrolyte interface or a pseudocapacitance resulted from a fast reversible faradic process of redox-active materials (e.g., metal oxides or conductive polymers). For an EDLC-based capacitor, the rapid charge/ discharge process provides the capacitor with a high power density, yet the energy density is limited by its effective doublelayer area. To date, a large number of largesurface-area materials, such as activated carbon, templated carbon, and carbon nanotubes (CNTs), have been extensively studied. Activated carbons, with surface areas from 1 000-2 500 m 2 g À1 , are the most commonly used materials and may provide a capacitance up to 320 F g À1 at low potential scanning rate. However, the capacitance may drop dramatically at high scanning rates because of their tortuous pore structure and high microporosity. [3] The templated carbons, on the other hand, exhibit uniform pore geometry and larger pore size; however, they have not shown any significant improvement in either energy or power performance. [4] For comparison, multiwalled CNTs [5] show capacitances up to 135 F g À1 and single-wall CNTs [6] show capacitances up to 180 F g À1 , which are still low for an actual device application. Compared with the EDLC-based capacitors, pseudocapacitors based on transition metal oxides or conducting polymers, such as RuO 2 , [7] MnO 2 , [8] NiO, [9] Co 3 O 4 , [10] V 2 O 5 , [11] and polyaniline, [12] may provide much higher specific capacitances, up to 1 000 F g À1 of the active material. Nonetheless, their actual applications are still limited by high cost, low operation voltage, or poor rate capability, mostly because of inefficient mass transport or of slow faradic redox kinetics. To design a better electrochemical capacitor with both high energy and power density, a common strategy is to construct a hybrid capacitor that integrates both electric double-layer capacitance and pseudocapacitance within a single electrode. For example, Sato et al. loaded ruthenium oxide onto activated carbon, resulting in a capacity of 308 F g À1 at 7.1 wt% ruthenium loading and a low scanning rate of 2 mV s À1. [13] Dong et al. reported a composite of MnO 2 and templated carbon with a capacitance of 156 F g À1 at 20 wt% MnO 2 loading and a scanning rate of 50 mV s À1 , which is about two times of that of the constituent carbon. [14] Kim et al. dispersed ruthenium oxide nanoparticles on carboxylated CNTs and obtained a total capacitance of 304 Fg À1 at a RuO 2 loading of 50 wt%. [15] Similarly, composites prepared by electrodepositing MnO 2 on vertically aligned CNT arrays exhibit

- by qiangfeng xiao
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- Engineering, Electrochemistry, Carbon Nanotubes, Nanocomposites

Ascorbic acid degradation kinetics of sonicated orange juice during storage were determined and compared to thermally pasteurised samples. Acoustic energy densities (AED) ranging from 0.30 to 0.81 W/mL and treatment times of 2-10 min were investigated. The degradation kinetics of sonicated samples followed first-order kinetics (R 2 ! 0.91) during processing. During storage ascorbic acid degradation of sonicated samples followed the Weibull model (R 2 ! 0.97) with b values ranging from 0.662 to 0.697. Comparatively, first-order degradation kinetics were observed during storage for thermally pasteurised (R 2 ¼ 0.98) and control samples (R 2 ¼ 0.96). Increased shelf life based on ascorbic acid retention was found for sonicated samples compared to thermally pasteurised samples. Predicted shelf life for sonicated orange juice ranged from 27 to 33 days compared to 19 days for thermally pasteurised juice during storage at 10 C. These results indicate that sonication results in enhanced retention of ascorbic acid in orange juice during storage compared to thermal processing.

- by Brijesh Tiwari
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- Kinetics, High Energy Density Physics, Animal Production, SHELF LIFE

In the absence of capillarity the single-component two-phase porous medium equations have the structure of a nonlinear parabolic pressure (equivalently, temperature) diffusion equation, with derivative coupling to a nonlinear hyperbolic saturation wave equation. The mixed parabolic-hyperbolic system is capable of substaining saturation shock waves. The Rankine-Hugoniot equations show that the volume flux is continuous across such a shock.

- by Mark J McGuinness
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- Chemical Engineering, Civil Engineering, Applied Mathematics, Two Phase Flow

Commercial supercapacitors, also known as ultracapacitors or electrochemical capacitors, from Saft, Maxwell, Panasonic, CCR, Ness, EPCOS, and Power Systems were tested under constant current and constant power discharges to assess their applicability for power-assist applications in hybrid electric vehicles (HEVs). Commercial lithium-ion batteries from Saft and Shin-Kobe were also tested under similar conditions. Internal resistances were measured by electrochemical impedance spectroscopy (EIS), as well as by the ''iR drop'' method. Self discharge measurements were also recorded. Compared with earlier generations of supercapacitors, the cells showed improved current and power capability. However, their energy densities are still too low to meet goals set by Partnership for a New Generation of Vehicles (PNGV) for HEV propulsion. Cells that use acetonitrile as the electrolyte solvent yield better performance, although safety issues need to be addressed. New high-power lithium-ion batteries show high energy densities, with high power capabilities.

- by Paul Braatz
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- Engineering, Power System, Performance, High Energy Density Physics

LiNiPO 4 belongs to a family of olivine type compounds, with members LiMPO 4 where M = Fe, Mn, Co or Ni are transition metals. The lithium nickel phosphate was prepared and characterized in order to evaluate a new potential cathode material for our ongoing research in aqueous rechargeable batteries. Annealing the final product is critical in obtaining the stoichiometric LiNiPO 4 pure phase; conventional cooling to a room temperature leads to an indication of Li 3 PO 4 and NiO secondary phases as impurities. The synchrotron infrared radiation (SR-IR) as a source for IR spectroscopy pins down the differences in the chemical bonding for annealed and conventional cooled LiNiPO 4 samples. The cyclic voltammetric and galvanostatic studies showed annealed LiNiPO 4 is electrochemically active from which lithium ions can be de-intercalated during oxidation process leading to an amorphous NiPO 4 and a minor product of nickel(II) hydroxide (␤-NiOOH). During subsequent reduction, lithium ions are not fully intercalated, however, the structure is reversible and adequate for multiple cycles. The high potential in LiNiPO 4 looks to be very attractive in terms of high energy density, given the efficiency is improved.

- by Dominique Appadoo
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- Engineering, High Energy Density Physics, Annealing, Physical sciences

A 97-day-long record on waves and currents was obtained using wave rider buoy and current meter moored at 2.5 km off Gopalpur from 19 May to 23 August 2008 representing southwest monsoon months. A Valeport tide gauge was used to record water level at Gopalpur port. Simultaneously, beach profiles at 4 transects were monitored using real-time kinematic (RTK) global positioning system (GPS). A total of 636,167 waves were analyzed for the period; a range of 3,200-9,700 waves approach the coast in an individual day. During the study, unusual characteristics of wave were observed on July 29, 2008, with a magnitude of significant wave height, H s = 2.85 m, maximum wave height, H max = 5.22 m, and peak wave period, T p = 10.2 s, and on August 11, 2008, with H s = 2.28 m, H max = 5.37 m, and T p = 11.1 s. Significant beach loss was noticed during these periods, and severe erosion was recorded on August 1, 2008. Beach profile data indicates that 18-58 cu. m/m sediment was lost during the study period. The paper provides an overview of the statistical analysis of wave heights, periods, direction, and spectral energy density and explains the cause of coastal erosion and loss of sediment.

- by DR. PRAVAKAR MISHRA and +1
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- Psychology, Statistical Analysis, Natural Hazards, High Energy Density Physics

Electrochemical double-layer capacitors, or supercapacitors, have tremendous potential as high-power energy sources for use in low-weight hybrid systems for space exploration. Electrodes based on single-wall carbon nanotubes (SWCNTs) offer exceptional power and energy performance due to the high surface area, high conductivity, and the ability to functionalize the SWCNTs to optimize capacitor properties. 1 This paper will report on the preparation of electrochemical capacitors incor-

- by Sivaram Arepalli and +2
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- Materials Engineering, Mechanical Engineering, Carbon Nanotube, High Energy Density Physics

Objectives. To describe CO 2 laser characteristics and to review the literature regarding its effects on caries inhibition in enamel and dentin. Another aim of this review is to discuss the effects of CO 2 laser in combination with... more

- by Lidiany Rodrigues
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- Dentistry, Carbon Dioxide, Hydroxyapatite, High Energy Density Physics

We present an exact solution of the n-dimensional (n > 4) vacuum Einstein field equations with a Bianchi type I metric. The solution may be interpreted as a four-dimensional anisotropic cosmological model. The extra dimensions are related to the energy density and pressures in the model. The physics of the results is discussed at the end of the paper.

A laser beam directed towards weeds can be an efficient weed control method as an alternative to herbicides. Lasers may deliver high-density energy to selected plant material, raising the temperature of the water in the plant cells and thereby stop or delay the growth. A commercial use of lasers for weed control, however, require a systematic investigation of the relationship between energy density and the biological effect on different weed species, growth stages, etc.

- by Solvejg Mathiassen and +1
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- Biomedical Engineering, High Energy Density Physics, Biosystems engineering, Research and Development
- by Helen Eyles
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- Nonparametric Statistics, Diet, High Energy Density Physics, Commerce

Lithiated layered transitional metal oxide materials of the LiMO2 type and especially LiCoO2 presents interesting specific properties as high energy density, long cycle life and constant discharging properties in a wide range of working conditions as well as a good safety. These properties made these materials excellent candidates as active compounds for high capacity cathode materials for rechargeable lithium batteries. LiCoO2 is the most common lithium storage material for lithium rechargeable batteries, used widely to power portable electronic devices. Operation of lithium rechargeable batteries is dependent on reversible lithium insertion and extraction processes into and from the host materials of lithium storage. In this study, LiCoO2 thin films were prepared by the sol–gel spin coating technique using metal acetate and citric acid as starting materials. Citric acid acts as a chelating agent, which promotes the preliminary reaction between lithium and cobalt and suppresses the precipitation of acetates. The sol–gel method is well known as one of promising thin-film preparation methods, which has good advantages such as low fabrication cost, relatively easy stoichiometry control, high deposition rate and also known as a low-temperature synthesis method for various ceramics. In addition, the crystal phases involved in the thin film can also be controlled by changing the chemical compositions of the sol. The crystallinity, microstructure and electrochemical properties of final films are also studied by XRD, SEM, AFM and galvanostatic charge/discharge cycling test. Films heat-treated under appropriate conditions exhibit high capacity and good crystallinity so those films are considered to be candidates as cathodes for thin-film micro batteries.

... WEI Ji-He(C&~), YU Neng-Wen(;~:~ FAN Yang-Yi(~), YANG Sen-Long(~&~), ... E 8 ] Hanna RK, Jones T, Blake RI and Millman M S. Water modelling to aid improvement of degasser performance for production of ultralow carbon... more

- by Fan Yang
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- Mass Transfer, Two Phase Flow, High Energy Density Physics, Shanghai

Obese children were randomly assigned to a family-based behavioral treatment that included either stimulus control or reinforcement to reduce sedentary behaviors. Significant and equivalent decreases in sedentary behavior and high energy density foods, increases in physical activity and fruits and vegetables, and decreases in standardized body mass index (z-BMI) were observed. Children who substituted active for sedentary behaviors had significantly greater z-BMI changes at 6 (-1.21 vs. -0.76) and 12 (-1.05 vs. -0.51) months, respectively. Substitution of physically active for sedentary behaviors and changes in activity level predicted 6-and 12-month z-BMI changes. Results suggest stimulus control and reinforcing reduced sedentary behaviors are equivalent ways to decrease sedentary behaviors, and behavioral economic relationships in eating and activity may mediate the effects of treatment.

- by Hollie Raynor
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- Health Psychology, Education, Health Promotion, Obesity

Hybrid plasma catalyst technology has great potential for indoor air purification. However, humidity is a critical parameter in plasma catalytic processes. In this work, several catalysts were tested downstream of a DC corona discharge and the effect of humidity was investigated on both ozone and toluene removal. Next, sorption measurements onto the catalysts were performed for toluene, trichloroethylene and acetone, using an equilibrium partitioning in closed system procedure to explain the obtained results in a quantitative manner.

- by jim van durme
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- Environmental Engineering, Chemical Engineering, Technology, Catalysis

A new method has been applied for the study of intermittency in the collisions of 28 Si + AgBr at 14.6 A GeV for the produced relativistic charged particles by using the method of mixed factorial moment (MFM). In this paper an analysis has been made for the presence of fractal behavior with three different approaches of Scaled factorial Moments (SFMs) named as-horizontal, vertical and mixed (horizontal and vertical together). The non-statistical fluctuations of relativistic charged particles have been calculated on events with different degree of centrality. These results have been compared with the results of simulated data obtained from UrQMD model and we find a good agreement between experimental data and simulated data.

It seems that many people, including dietetics professionals and other nutrition experts, are unclear about some of the fundamental yet complex concepts behind the influence of dietary macronutrients (ie, protein, carbohydrate, and fat) on appetite regulation. Recent research has begun to unravel some of the more complicated physiological processes of appetite control and regulation generated by hormones such as leptin, ghrelin, and the gut hormone peptide YY3-35. Although the processes by which the macronutrients in our foods influence appetite regulation have been a topic of study for decades, they remain confusing and are often misunderstood. The objective of this article is to define the terminology commonly used to discuss the macronutrients' roles in appetite regulation and to discuss the interrelated concepts and roles of taste, palatability, and energy density.

- by Adam Drewnowski and +1
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- High Energy Density Physics, Hunger, Appetite, Taste

The response of cemented tungsten carbide and of titanium carbonitride was investigated with respect to damage and ablation properties, under interaction with ultrashort laser pulses. These carbide materials present high microhardness and are of signi®cant interest for tribological applications. The experiments were carried out in air with a commercial Ti:sapphire laser at energy densities on the target up to 6.5 J/cm 2 . The irradiated target surfaces were analyzed with optical, SEM and AFM techniques and the damage and ablation threshold values were determined using the measured spot diameters and the calculated incident energy density distributions. #

- by Valerio Romano
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- Titanium, High Energy Density Physics, Multidisciplinary, Abrasive wear

Laser cladding is becoming an emergent process with high interest for industries dedicated to high added value parts production. Laser cladding introduces new manufacturing concepts such as direct manufacturing of parts, avoiding in this way the excessive waste of material in the form of chips, inherent to traditional machining processes. This process is based on the use of a source of high energy density, such as laser beams, to generate a melt pool on a substrate where a filler material is injected. Thus, when studying the process it is necessary to know the effective energy that reaches the base material. This energy does not correspond to the one provided by the laser beam, considering that the laser beam has to go through a cloud of injected powder before it reaches the substrate. In this region there is an interaction between the laser beam and the filler material in which a significant amount of energy is absorbed by the powder. As a result, attenuation values can reach up to high percentages of the initial energy value.

Lithium-ion-based battery energy storage system has started to become the most popular form of energy storage system for its high charge and discharge efficiency and high energy density. This paper proposes a high-efficiency grid-tie lithium-ion-battery- based energy storage system, which consists of a LiFePO4 -battery- based energy storage and a high-efficiency bidirectional ac-dc converter. The battery management system estimates the

- by Wensong Yu and +1
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- Computer Architecture, High Energy Density Physics, Lithium Ion Battery, Energy Storage

Recent data from the World Health Organization showed that about 60% of all deaths, occurring among children aged less than five years (under-five children) in developing countries, could be attributed to malnutrition. It has been estimated that nearly 50.6 million under-five children are malnourished, and almost 90% of these children are from developing countries. Bangladesh is one of the countries with the highest rate of malnutrition. The recent baseline survey by the National Nutrition Programme (NNP) showed high rates of stunting, underweight, and wasting. However, data from the nutrition surveillance at the ICDDR,B hospital showed that the proportion of children with stunting, underweight, and wasting has actually reduced during 1984-2005. Inappropriate infant and young child-feeding practices (breastfeeding and complementary feeding) have been identified as a major cause of malnutrition. In Bangladesh, although the median duration of breastfeeding is about 30 months, the rate of exclusive breastfeeding until the first six months of life is low, and practice of appropriate complementary feeding is not satisfactory. Different surveys done by the Bangladesh Demographic and Health Survey, United Nations Children's Fund (UNICEF), and Bangladesh Breastfeeding Foundation (BBF) showed a rate of exclusive breastfeeding to be around 32-52%, which have actually remained same or declined over time. The NNP baseline survey using a strict definition of exclusive breastfeeding showed a rate of exclusive breastfeeding (12.8%) until six months of age. Another study from the Abhoynagar field site of ICDDR,B reported the prevalence of exclusive breastfeeding to be 15% only. Considerable efforts have been made to improve the rates of exclusive breastfeeding. Nationally, initiation of breastfeeding within one hour of birth, feeding colostrum, and exclusive breastfeeding have been promoted through the Baby-Friendly Hospital Initiative (BFHI) implemented and supported by BBF and UNICEF respectively. Since most (87-91%) deliveries take place in home, the BFHI has a limited impact on the breastfeeding practices. Results of a few studies done at ICDDR,B and elsewhere in developing countries showed that the breastfeeding peer-counselling method could substantially increase the rates of exclusive breastfeeding. Results of a study in urban Dhaka showed that the rate of exclusive breastfeeding was 70% among mothers who were counselled compared to only 6% who were not counselled. Results of another study in rural Bangladesh showed that peer-counselling given either individually or in a group improved the rate of exclusive breastfeeding from 89% to 81% compared to those mothers who received regular health messages only. This implies that scaling up peercounselling methods and incorporation of breastfeeding counselling in the existing maternal and child heath programme is needed to achieve the Millennium Development Goal of improving child survival. The recent data showed that the prevalence of starting complementary food among infants aged 6-9 months had increased substantially with 76% in the current dataset. However, the adequacy, frequency, and energy density of the complementary food are in question. Remarkable advances have been made in the hospital management of severely-malnourished children. The protocolized management of severe protein-energy malnutrition at the Dhaka hospital of ICDDR,B has reduced the rate of hospital mortality by 50%. A recent study at ICDDR,B has also documented that home-based management of severe protein-energy malnutrition without follow-up was comparable with a hospital-based protocolized management. Although the community nutrition centres of the NNP have been providing food supplementation and performing growth monitoring of children with protein-energy malnutrition, the referral system and management of complicated severely-malnourished children are still not in place.

- by Iqbal Hossain
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- Demography, Nutrition and Dietetics, United Nations, Health

Solid polymer electrolytes based on poly (vinyl alcohol) (PVA) complexed with sodium fluoride (NaF) at different weight percent ratios were prepared using solution cast technique. The structural properties of these electrolyte films were examined by XRD studies. The XRD data revealed that the amorphous domains of PVA polymer matrix increased with increase of NaF salt concentration. The complexation of the salt with the polymer was confirmed by FT-IR studies. Electrical conductivity was measured in the temperature range of 303-373 K and the conductivity was found to increase with the increase of dopant concentration as well as temperature. The dielectric constant (e 0 ) increased with the increase in temperature and decreased with the increase in frequency. A loss peak was identified at 365 K in the dielectric loss spectra and is attributed to the orientation of polar groups. Measurement of transference number was carried out to investigate the nature of charge transport in these polymer electrolyte films using Wagner's polarization technique and Watanabe technique. Transport number data showed that the charge transport in these polymer electrolyte systems was predominantly due to ions and in particular due to anions. Using these polymer electrolytes, solid state electrochemical cells were fabricated. Various cell parameters like open circuit voltage (OCV), short circuit current (SCC), power density and energy density were determined.

The electrical characteristics and design features of a low inductance, compact, 500 kV, 500 J, 10 Hz repetition rate, Marx generator are discussed. While benefiting from the large energy density of mica capacitors, 4 mica capacitors were utilized in parallel per stage, keeping the parasitic inductance per stage low. Including the sparkgap switches, a stage inductance of 55 nH was measured, which translates with 100 nF capacitance per stage to ~ 18.5 Ω characteristic Marx impedance. Using solely inductors, ~ 1 mH each, as charging elements instead of resistors enabled charging the Marx within less than 100 ms with little charging losses. The pulse width of the Marx into a matched resistive load is about 200 ns with 50 ns rise-time. Repetitive HPM generation with the Marx directly driving a small Vircator has been verified. The Marx is fitted into a tube with 30 cm diameter and a total length of 0.7 m. We discuss the Marx operation at up to 21 kV charging voltage per stage, with repetition rates of up to 10 Hz in burst mode primarily into resistive loads. A lumped circuit description of the Marx is also given, closely matching the experimental results.

- by Andreas Neuber
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- High Energy Density Physics, Pulsed Power, Total Length

Production of ethanol (bioethanol) from biomass is one way to reduce both consumption of crude oil and environmental pollution. Bioethanol is appropriate for the mixed fuel in the gasoline engine because of its high octane number, and its low cetane number and high heat of vaporization impede self-ignition in the diesel engine. So, ignition improver, glow-plug, surface ignition, and pilot injection are applied to promote self-ignition by using diesel-bioethanol-blended fuel. Disadvantages of bioethanol include its lower energy density than gasoline, its corrosiveness, low flame luminosity, lower vapor pressure (making cold starts difficult), miscibility with water, and toxicity to ecosystems. Bioethanol can be produced from cellulosic feedstocks. One major problem with bioethanol production is the availability of raw materials for the production. The availability of feedstocks for bioethanol can vary considerably from season to season and depends on geographic locations. Lignocellulosic biomass is the most promising feedstock considering its great availability and low cost, but the large-scale commercial production of fuel bioethanol from lignocellulosic materials has still not been implemented. Conversion technologies for producing bioethanol from cellulosic biomass resources such as forest materials, agricultural residues and urban wastes are under development and have not yet been demonstrated commercially. For designing fuel bioethanol production processes, assessment of utilization of different feedstocks (i.e. sucrose containing, starchy materials, lignocellulosic biomass) is required considering the big share of raw materials in bioethanol costs. In this work a review of the biological and thermochemical methods that could be used to produce bioethanol is made and an analysis of its global production trends is carried out. r

Extrusion cooking is a useful process for the production of instant infant flours, as it allows gelatinisation and partial dextrinisation of starch, as well as reduction of the activity of some antinutritional factors. But existing extrusion equipment is not suited to the context of developing countries as it requires considerable financial investment and the production capacity (minimum 300 kg/h) is too high. The aim of our study was to improve traditional extruders with low production capacity (about 30 kg/h) manufactured in Vietnam and to test their performance in the production of infant flours. Several blends made with rice, sesame and/or soybean have been extruded with the modified equipment that we name ''very low-cost extruder''. In the case of blends containing soybean, starch gelatinisation was not complete, and decreased with an increase in the lipid content of the blend. The rate of trypsin inhibitor destruction evolved in a similar way. Adding water before extrusion, or extruding the blends twice was not effective in increasing the rates of starch gelatinisation or trypsin inhibitor destruction. However, the ''very low-cost extruder'' proved its ability to process the rice-sesame blend that had a lipid content of less than 6 g/100 g DM, and low initial water content [around 10%, wet basis (wb)]. In this case, extrusion led to total starch gelatinisation and the extent of starch dextrinisation, which was measured by comparing the viscosity of gruels prepared from crude and corresponding extruded blends, was sufficient to prepare gruels with substantially increased energy density. With the addition of roasted soybean flour, sugar, milk powder, vitamins and minerals, this blend could provide a nutritious instant flour usable as complementary food for infants and young children. #

- by nguyen le hoan
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- High Energy Density Physics, Food Chemistry, Vietnam, Multidisciplinary

Several advanced technologies are introduced in automotive applications. Higher energy density and dynamic performance are demanding new and cost-effective actuator structures. Magnetostriction (MS), change in shape of materials under the influence of an external magnetic field, is one of the advanced technologies. Good understanding of specific design constrains is required to define and optimize a magnetostrictive actuator. This paper presents parametrical analysis with magnetic simulation of a magnetostrictive actuator. Proposed actuator has been designed, and the performance has been evaluated on experimental rig. Strain, elongation of the shaft, of 1000 ppm at 10 A and a blocked force over 4500 N has been achieved with shaft of 8 mm diameter, made of Terfenol-D. Furthermore, the effect of pre-stress of the Terfenol-D shaft has been evaluated experimentally. The study shows that excellent features can be obtained by magnetostrictive materials for many advanced applications.

- by Arthur Grunwald
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- Materials Engineering, Mechanical Engineering, FEM, High Energy Density Physics

We investigate the Yilmaz Cosmology by working out the Friedmann-type equations generated by assuming the Cosmological metric for a flat space for the Yilmaz theory of gravitation. In the case of matter-conserving Cosmologies we find the theory demands that the total energy density of the Cosmological fluid is zero. No configuration of vacuum radiation and inert matter can be found that is both compatible with this constraint and with observation. The steady-state Cosmology may, however, be viable.

- by Michael Ibison
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- General Relativity, High Energy Density Physics, Steady state

Wave attenuation was studied in a coastal mangrove system in the Red River Delta, Vietnam on the coast north of Do Son. From sea towards land the study area consisted of a bare mudflat, covered by a sandy layer with embryonic cheniers, abruptly changing into a muddy tidal flat overgrown with mangroves. Three instrumented tripods (A-C) placed in a cross-shore profile, were used to measure current velocity and water level, at the open tidal flat, at the beginning of the mangrove vegetation, and in the mangrove vegetation, respectively. Measurements were conducted in the wet season in July and August 2000. The elevation of the area was surveyed using a levelling instrument. Over the bare sandy surface of the mudflat, the incoming waves are reduced in height (and energy density) due to bottom friction. This reduction decreases with increasing water depth. In the mangrove vegetation, the bottom friction exerted by the clay particles is very low. However, the dense network of trunks, branches and above ground roots of the mangrove vegetation causes a much higher drag force. For the mangrove vegetation which mainly consists of Kandelia candel, the drag force can be approached by the function C D = 0.6e 0.15A (with A being the projected cross-sectional area of the under water obstacles at a certain water depth). For the same muddy surface without mangroves the function would be C D = 0.6.

- by Aart Kroon
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- Geology, Geochemistry, Geophysics, High Energy Density Physics

In this study, ammonia is identified as a sustainable fuel for mobile and remote applications. Similar to hydrogen, ammonia is a synthetic product that can be obtained either from fossil fuels, biomass, or other renewable sources. Some advantages of ammonia with respect to hydrogen are less expensive cost per unit of stored energy, higher volumetric energy density that is comparable with that of gasoline, easier production, handling and distribution with the existent infrastructure, and better commercial viability. Here, the possible ways to use ammonia as a sustainable fuel in internal combustion engines and fuelcells are discussed and analysed based on some thermodynamic performance models through efficiency and effectiveness parameters. The refrigeration effect of ammonia, which is another advantage, is also included in the efficiency calculations. The study suggests that the most efficient system is based on fuelcells which provide simultaneously power, heating and cooling and its only exhaust consists of water and nitrogen. If the cooling effect is taken into consideration, the system's effectiveness reaches 46% implying that a medium size car ranges over 500 km with 50 l fuel at a cost below $2 per 100 km. The cooling power represents about 7.2% from the engine power, being thus a valuable side benefit of ammonia's presence on-board.

- by Calin Zamfirescu
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- Engineering, Thermodynamics, High Energy Density Physics, Fuel Cell

This paper presents a convenient calculation formula of energy density for nuclear fuel or nuclear battery that outputs energy by whatever decay. Also a relative formula is deduced for easy comparison between different fuels. At last, with the convenient formula, the energy density comparison and possibility of applying different isomer beta fuels are proactively calculated and aggressively discussed.

- by Yanming Wei
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- High Energy Density Physics, Nuclear Energy, Beta decay, Transmutation

- by Pål Kolstø
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- Management, Ecological Engineering, Optical Engineering, Biochemistry

Sulfone-based electrolytes have been investigated as electrolytes for lithium-ion cells using high-voltage positive electrodes, such as LiMn 2 O 4 and LiNi 0.5 Mn 1.5 O 4 spinels, and Li 4 Ti 5 O 12 spinel as negative electrode. In the presence of imide salt (LiTFSI) and ethyl methyl sulfone or tetramethyl sulfone (TMS) electrolytes, the Li 4 Ti 5 O 12 /LiMn 2 O 4 cell exhibited a specific capacity of 80 mAh g À1 with an excellent capacity retention after 100 cycles. In a cell with high-voltage LiNi 0.5 Mn 1.5 O 4 positive electrode and 1 M LiPF 6 in TMS as electrolyte, the capacity reached 110 mAh g À1 at the C/12 rate. When TMS was blended with ethyl methyl carbonate, the Li 4 Ti 5 O 12 /LiNi 0.5 Mn 1.5 O 4 cell delivered an initial capacity of 80 mAh g À1 and cycled fairly well for 1000 cycles under 2C rate. The exceptional electrochemical stability of the sulfone electrolytes and their compatibility with the Li 4 Ti 5 O 12 safer and stable anode were the main reason behind the outstanding electrochemical performance observed with high-potential spinel cathode materials. These electrolytes could be promising alternative electrolytes for high-energy density battery applications such as plug-in hybrid and electric vehicles that require a long cycle life.

- by Ilias Belharouak
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- Engineering, High Energy Density Physics, High Voltage, Electric Vehicle

A formal proof to relate the concept of electromagnetic local density of states (LDOS) to the electric and magnetic dyadic Green's functions is provided. The expression for LDOS is obtained by relating the electromagnetic energy density at any location in a medium at uniform temperature T to the electric and magnetic dyadic Green's functions. With this the concept of LDOS is also extended to material media. The LDOS is split into two terms -one that originates from the energy density in an infinite, homogeneous medium and the other that takes into account scattering from inhomogenieties. The second part can always be defined unambiguously, even in lossy materials.

The onset of piloted ignition (flash point) of combustible polymers is predicted by a gas phase combustion energy density of 1.9 MJ/m 3 that describes the lower flammability limit of fuel vapor-air mixtures. The mass flux (1 g/m 2 s) and (virtual) heat release rate (24 kW/m 2 ) of the solid at incipient ignition derived from this observation are in general agreement with experimental data for piloted ignition of plastics. Sustained ignition marks the transition from lower-limit to stoichiometric burning and the critical heat release rate increases proportionally to 66 kW/m 2 . A critical heat release rate, unique among ignition criteria, is independent of material composition because of the implicit coupling between the gas and condensed phase processes. Published by Elsevier Inc. on behalf of The Combustion Institute.

- by James Quintiere
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- Mechanical Engineering, Chemical Engineering, Mass Transfer, Combustion

The increasingly demand on secondary batteries with higher specific energy densities requires the replacement of the actual electrode materials. With a very high theoretical capacity (4200 mAh g 1 ) at low voltage, silicon is presented as a very interesting potential candidate as negative electrode for lithium-ion microbatteries. For the first time, the electrochemical lithium alloying/de-alloying process is proven to occur, respectively, at 0.15 V/0.45 V vs. Li + /Li with Si nanowires (SiNWs, 200-300 nm in diameter) synthesized by chemical vapour deposition. This new three-dimensional architecture material is well suited to accommodate the expected large volume expansion due to the reversible formation of Li-Si alloys. At present, stable capacity over ten to twenty cycles is demonstrated. The storage capacity is shown to increase with the growth temperature by a factor 3 as the temperature varies from 525 to 575 • C. These results, showing an attractive working potential and large storage capacities, open up a new promising field of research.

- by Costel Cojocaru
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- Engineering, High Energy Density Physics, Nanowires, Thin Film