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Sample records for cooled flexible conversion

  1. Flexible Conversion Ratio Fast Reactor Systems Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Neil Todreas; Pavel Hejzlar

    2008-06-30

    Conceptual designs of lead-cooled and liquid salt-cooled fast flexible conversion ratio reactors were developed. Both concepts have cores reated at 2400 MWt placed in a large-pool-type vessel with dual-free level, which also contains four intermediate heat exchanges coupling a primary coolant to a compact and efficient supercritical CO2 Brayton cycle power conversion system. Decay heat is removed passively using an enhanced Reactor Vessel Auxiliary Cooling System and a Passive Secondary Auxiliary Cooling System. The most important findings were that (1) it is feasible to design the lead-cooled and salt-cooled reactor with the flexible conversion ratio (CR) in the range of CR=0 and CR=1 n a manner that achieves inherent reactor shutdown in unprotected accidents, (2) the salt-cooled reactor requires Lithium thermal Expansion Modules to overcme the inherent salt coolant's large positive coolant temperature reactivity coefficient, (3) the preferable salt for fast spectrum high power density cores is NaCl-Kcl-MgCl2 as opposed to fluoride salts due to its better themal-hydraulic and neutronic characteristics, and (4) both reactor, but attain power density 3 times smaller than that of the sodium-cooled reactor.

  2. Study on water cooled high conversion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ochiai, Masaaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-12-01

    As a part of study on advanced reactors for the future, conceptual design of high conversion water cooled reactors is being studied, aiming at the contribution to nuclear fuel cycle by the LWR technology, since the utilization of LWRs will extend over a long period of time . We are studying on the reactor core concepts for BWR and PWR reactor systems. As for BWR system, three types of reactor cores are investigating for three different design goals; long operation period, high conversion ratio and high applicability for the existing BWR system. In all the cases, we have obtained a fair prospect of a large core concept with a capacity of 1,000 MWe class having negative void reactivity coefficient. This study is a part of JAERI-JAPCO (Japan Atomic Power Company) cooperative studies. Various kinds of conceptual designs will be created until the end of FY 1999. The designs will be checked and reviewed at that time, then experimental studies on the realization of the concepts will start with further design works from FY 2000. (author)

  3. Flexible Transpiration Cooled Thermal Protection System for Inflatable Atmospheric Capture and Entry Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Andrews Space, Inc. proposes an innovative transpiration cooled aerobrake TPS design that is thermally protective, structurally flexible, and lightweight. This...

  4. Mathematic modeling on flexible cooling system in hot strip mill

    Institute of Scientific and Technical Information of China (English)

    彭良贵; 刘相华; 赵宪明; 吴迪

    2014-01-01

    A novel cooling system combining ultra fast cooling rigs with laminar cooling devices was investigated. Based on the different cooling mechanisms, a serial of mathematic models were established to describe the relationship between water flow and spraying pressure and the relationship between water spraying heat flux and layout of nozzles installed on the top and bottom cooling headers. Model parameters were validated by measured data. Heat transfer models including air convection model, heat radiation model and water cooling capacity model were detailedly introduced. In addition, effects on cooling capacity by water temperature and different valve patterns were also presented. Finally, the comparison results from UFC used or not have been provided with respect to temperature evolution and mechanical properties of Q235B steel grade with thickness of 7.8 mm. Since online application of the sophisticated CTC process control system based on these models, run-out table cooling control system has been running stably and reliably to produce resource-saving, low-cost steels with smaller grain size.

  5. Effect of Cooling Methods on Methane Conversion via Dielectric-Barrier Discharges

    Institute of Scientific and Technical Information of China (English)

    WANG Baowei; YANG Kuanhui; XU Genhui

    2008-01-01

    Effects of cooling methods on stability and methane conversion rate using dielectricbarrier discharges (DBD) were systematically investigated in this article.The results showed that the methane conversion rate was as high as 44.43% in a pure methane system at a flow rate of 100 mL.min-1 and an input power of 234.2 W with air cooling.A dark greenish and soft film-like carbon was deposited on the outer surface of quartz tube when the outer electrode was watercooled,which decreased the methane conversion.With air cooling of inner electrode the selectivity of C2 hydrocarbons was higher than that with other cooling methods,while the C3 hydrocarbons had higher selectivity with flowing water cooling.Cooling the inner electrode could restrain the carbon deposition,but would decrease the methane conversion rate.The stability of both reaction and plasma operation can be improved through cooling the reactor.From thermodynamic analysis,it was found that the effective collisions frequency among the reactant molecules and free electrons (e-) increased with temperature,which in turn led to a higher methane conversion rate and a change in the distribution of products.

  6. Preliminary Neutronic Study of D2O-cooled High Conversion PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Hikaru Hiruta; Gilles Youinou

    2013-10-01

    This paper presents a preliminary neutronics analysis of tight-pitch D2O-cooled high-conversion PWRs loaded with MOX fuel aiming at high Pu conversion and negative void coefficient. SCALE6.1 has been exclusively utilized for this study. The analyses are performed in two separate parts. The first part of this paper investigates the performance of axial and internal blankets and seeks break-even or near-breeder core even without the presence of radial blankets. The second part of this paper performs sensitivity and uncertainty analyses of integral parameters (keff and void coefficient) for selected systems in order to analyze the characters of this high-conversion PWR from different aspects.

  7. Fuel Economy and Emissions of a Vehicle Equipped with an Aftermarket Flexible-Fuel Conversion Kit

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, John F [ORNL; Huff, Shean P [ORNL; West, Brian H [ORNL

    2012-04-01

    The U.S. Environmental Protection Agency (EPA) grants Certificates of Conformity for alternative fuel conversion systems and also offers other forms of premarket registration of conversion kits for use in vehicles more than two model years old. Use of alternative fuels such as ethanol, natural gas, and propane are encouraged by the Energy Policy Act of 1992. Several original equipment manufacturers (OEMs) produce emissions-certified vehicles capable of using alternative fuels, and several alternative fuel conversion system manufacturers produce EPA-approved conversion systems for a variety of alternative fuels and vehicle types. To date, only one manufacturer (Flex Fuel U.S.) has received EPA certifications for ethanol fuel (E85) conversion kits. This report details an independent evaluation of a vehicle with a legal installation of a Flex Fuel U.S. conversion kit. A 2006 Dodge Charger was baseline tested with ethanol-free certification gasoline (E0) and E20 (gasoline with 20 vol % ethanol), converted to flex-fuel operation via installation of a Flex Box Smart Kit from Flex Fuel U.S., and retested with E0, E20, E50, and E81. Test cycles included the Federal Test Procedure (FTP or city cycle), the highway fuel economy test (HFET), and the US06 test (aggressive driving test). Averaged test results show that the vehicle was emissions compliant on E0 in the OEM condition (before conversion) and compliant on all test fuels after conversion. Average nitrogen oxide (NOx) emissions exceeded the Tier 2/Bin 5 intermediate life NO{sub X} standard with E20 fuel in the OEM condition due to two of three test results exceeding this standard [note that E20 is not a legal fuel for non-flexible-fuel vehicles (non-FFVs)]. In addition, one E0 test result before conversion and one E20 test result after conversion exceeded the NOX standard, although the average result in these two cases was below the standard. Emissions of ethanol and acetaldehyde increased with increasing ethanol

  8. Piping Flexibility Analysis of the Primary Cooling System of TRIGA 2000 Bandung Reactor due to Earthquake

    Directory of Open Access Journals (Sweden)

    H.P. Rahardjo

    2011-08-01

    Full Text Available Earthquakes in a nuclear installation can overload a piping system which is not flexible enough. These loads can be forces, moments and stresses working on the pipes or equipments. If the load is too large and exceed the allowable limits, the piping and equipment can be damaged and lead to overall system operation failure. The load received by piping systems can be reduced by making adequate piping flexibility, so all the loads can be transmitted homogenously throughout the pipe without load concentration at certain point. In this research the analysis of piping stress has been conducted to determine the size of loads that occured in the piping of primary cooling system of TRIGA 2000 Reactor, Bandung if an earthquake happened in the reactor site. The analysis was performed using Caesar II software-based finite element method. The ASME code B31.1 arranging the design of piping systems for power generating system (Power Piping Code was used as reference analysis method. Modeling of piping systems was based on the cooling piping that has already been installed and the existing data reported in Safety Analysis Reports (SARs of TRIGA 2000 reactor, Bandung. The quake considered in this analysis is the earthquake that occurred due to the Lembang fault, since it has the Peak Ground Acceleration (PGA in the Bandung TRIGA 2000 reactor site. The analysis results showed that in the static condition for sustain and expansion loads, the stress fraction in all piping lines does not exceed the allowable limit. However, during operation moment, in dynamic condition, the primary cooling system is less flexible at sustain load, ekspansi load, and combination load and the stress fraction have reached 95,5%. Therefore a pipeline modification (rerouting is needed to make pipe stress does not exceed the allowable stress. The pipeline modification was carried out by applied a gap of 3 mm in the X direction of the support at node 25 and eliminate the support at the node

  9. Flexibility.

    Science.gov (United States)

    Humphrey, L. Dennis

    1981-01-01

    Flexibility is an important aspect of all sports and recreational activities. Flexibility can be developed and maintained by stretching exercises. Exercises designed to develop flexibility in ankle joints, knees, hips, and the lower back are presented. (JN)

  10. Post-recombination early Universe cooling by translation-internal inter-conversion: The role of minor constituents.

    Science.gov (United States)

    McCaffery, Anthony J

    2015-09-14

    Little is known of the mechanism by which H and H2, the principal constituents of the post-re-combination early Universe, cooled sufficiently to permit cluster formation, nucleosynthesis, and, eventually, the formation of structured objects. Radiative decay primarily cools the internal modes of H2, as Δj = - 2 jumps accompany quadrupolar emission. This, however, would be a self-limiting mechanism. In this work, a translational energy cooling mechanism based on collision-induced, translation-to-internal mode conversion, is extended, following an earlier study [A. J. McCaffery and R. J. Marsh, J. Chem. Phys. 139, 234310 (2013)] of ensembles comprising H2 in a H atom bath gas. Here, the possible influence of minor species, such as HD, on this cooling mechanism is investigated. Results suggest that the influence of HD is small but not insignificant. Conversion is very rapid and an overall translation-to-internal energy conversion efficiency of some 5% could be expected. This finding may be of use in the further development of models of this complex phase of early Universe evolution. An unexpected finding in this study was that H2 + HD ensembles are capable of very rapid translation-to-internal conversion with efficiencies of >40% and relaxation rates that appear to be relatively slow. This may have potential as an energy storage mechanism.

  11. Post-recombination early Universe cooling by translation–internal inter-conversion: The role of minor constituents

    Energy Technology Data Exchange (ETDEWEB)

    McCaffery, Anthony J., E-mail: A.J.McCaffery@sussex.ac.uk [Department of Chemistry, University of Sussex, Brighton, BN1 9QJ Sussex (United Kingdom)

    2015-09-14

    Little is known of the mechanism by which H and H{sub 2}, the principal constituents of the post-re-combination early Universe, cooled sufficiently to permit cluster formation, nucleosynthesis, and, eventually, the formation of structured objects. Radiative decay primarily cools the internal modes of H{sub 2}, as Δj = − 2 jumps accompany quadrupolar emission. This, however, would be a self-limiting mechanism. In this work, a translational energy cooling mechanism based on collision-induced, translation-to-internal mode conversion, is extended, following an earlier study [A. J. McCaffery and R. J. Marsh, J. Chem. Phys. 139, 234310 (2013)] of ensembles comprising H{sub 2} in a H atom bath gas. Here, the possible influence of minor species, such as HD, on this cooling mechanism is investigated. Results suggest that the influence of HD is small but not insignificant. Conversion is very rapid and an overall translation-to-internal energy conversion efficiency of some 5% could be expected. This finding may be of use in the further development of models of this complex phase of early Universe evolution. An unexpected finding in this study was that H{sub 2} + HD ensembles are capable of very rapid translation-to-internal conversion with efficiencies of >40% and relaxation rates that appear to be relatively slow. This may have potential as an energy storage mechanism.

  12. Flexible Mode Control of Grid Connected Wind Energy Conversion System Using Wavelet

    Directory of Open Access Journals (Sweden)

    Bhavna Jain

    2015-01-01

    Full Text Available Small wind turbine systems offer services to critical loads during grid faults and also connected back to grid in normal condition. The connection of a wind energy conversion system to the grid requires a robust phase locked loop (PLL and continuous monitoring of the grid conditions such as overvoltage, undervoltage, overfrequency, underfrequency, and grid outages. This paper describes a flexible control operation to operate a small wind turbine in both stand-alone mode via planned islanding and grid connected mode as well. In particular, a proper monitoring and control algorithm is required for transition between the modes. A wavelet based energy function is used for detection of grid disturbances as well as recovery of grid so that transition between the modes is made. To obtain good power quality LCL filter is used to reduce ripples. PLL is used for synchronization whenever mode changes from stand-alone to grid connected. Simulation results from a 10 kW wind energy conversion system are included to show the usefulness of the proposed methods. The control method is tested by generated gate pulses for single phase bridge inverter using field programmable gate array (FPGA.

  13. Combining the Converse Humidity/Resistance Response Behaviors of RGO Films for Flexible Logic Devices

    KAUST Repository

    Tai, Yanlong

    2017-03-23

    Carbon nanomaterials have excellent humidity sensing performance. Here, we demonstrate that reduced-graphene-oxide- (rGO) based conductive films with different thermal reduction times have gradient and invertible humidity/electrical resistance responses: rGO films (< 11 h, negative response, regarded as a signal of “0”), rGO films (around 11-13 h, balance point) and rGO films (> 13 h, negative response, regarded as a signal of “1”). We propose a new mechanism that describes a “scale”-like model for rGO films to explain these behaviors based on contributions from Ohm-contact resistance and capacitive reactance at interplate junctions, and intrinsic resistances of the nanoplates, respectively. This mechanism is accordingly validated via a series of experiments and electrical impedance spectroscopies, which complement more classical models based on proton conductivity. To explore the practical applications of the converse humidity/resistance responses, three simple flexible logic devices were developed, i) a rGO pattern for humidity-insensitive conductive film, which has the potential to greatly improve the stability of carbon-based electrical device to humidity; ii) a Janus pattern of rGO films for gesture recognition, which is very useful to human/machine interactions; iii) a sandwich pattern of rGO films for 3-dimensional (3D) noncontact sensing, which will be complementary to existing 3D touch technique.

  14. Computing approximate blocking probability of inverse multiplexing and sub-band conversion in the flexible-grid optical networks

    Science.gov (United States)

    Gu, Yamei; You, Shanhong

    2016-07-01

    With the rapid growth of data rate, the optical network is evolving from fixed-grid to flexible-grid to provide spectrum-efficient and scalable transport of 100 Gb/s services and beyond. Also, the deployment of wavelength converter in the existing network can increase the flexibility of routing and wavelength allocation (RWA) and improve blocking performance of the optical networks. In this paper, we present a methodology for computing approximate blocking probabilities of the provision of multiclass services in the flexible-grid optical networks with sub-band spectrum conversion and inverse multiplexing respectively. Numerical calculation results based on the model are compared to the simulation results for the different cases. It is shown that the calculation results match well with the simulation results for the flexible-grid optical networks at different scenarios.

  15. Flexible spatial perspective-taking: Conversational partners weigh multiple cues in collaborative tasks

    Directory of Open Access Journals (Sweden)

    Alexia eGalati

    2013-09-01

    Full Text Available Research on spatial perspective-taking often focuses on the cognitive processes of isolated individuals as they adopt or maintain imagined perspectives. Collaborative studies of spatial perspective-taking typically examine speakers’ linguistic choices, while overlooking their underlying processes and representations. We review evidence from two collaborative experiments that examine the contribution of social and representational cues to spatial perspective choices in both language and the organization of spatial memory. Across experiments, speakers organized their memory representations according to the convergence of various cues. When layouts were randomly configured and did not afford intrinsic cues, speakers encoded their partner’s viewpoint in memory, if available, but did not use it as an organizing direction. On the other hand, when the layout afforded an intrinsic structure, speakers organized their spatial memories according to the person-centered perspective reinforced by the layout’s structure. Similarly, in descriptions, speakers considered multiple cues whether available a priori or at the interaction. They used partner-centered expressions more frequently (e.g., to your right when the partner’s viewpoint was misaligned by a small offset or coincided with the layout’s structure. Conversely, they used egocentric expressions more frequently when their own viewpoint coincided with the intrinsic structure or when the partner was misaligned by a computationally difficult, oblique offset. Based on these findings we advocate for a framework for flexible perspective-taking: people weigh multiple cues (including social ones to make attributions about the relative difficulty of perspective-taking for each partner, and adapt behavior to minimize their collective effort. This framework is not specialized for spatial reasoning but instead emerges from the same principles and memory-depended processes that govern perspective-taking in

  16. Flexible coordination of stationary and mobile conversations with gaze: Resource allocation among multiple joint activities

    Directory of Open Access Journals (Sweden)

    Eric Mayor

    2016-10-01

    Full Text Available Gaze is instrumental in coordinating face-to-face social interactions. But little is known about gaze use when social interactions co-occur with other joint activities. We investigated the case of walking while talking. We assessed how gaze gets allocated among various targets in mobile conversations, whether allocation of gaze to other targets affects conversational coordination, and whether reduced availability of gaze for conversational coordination affects conversational performance and content. In an experimental study, pairs were videotaped in four conditions of mobility (standing still, talking while walking along a straight-line itinerary, talking while walking along a complex itinerary, or walking along a complex itinerary with no conversational task. Gaze to partners was substantially reduced in mobile conversations, but gaze was still used to coordinate conversation via displays of mutual orientation, and conversational performance and content was not different between stationary and mobile conditions. Results expand the phenomena of multitasking to joint activities.

  17. Flexible High Energy-Conversion Sensing Materials for Structural Health Monitoring Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The applicant is developing flexible highly-efficient piezoelectric materials for use in structural health monitoring (SHM) as contemplated in the solicitation...

  18. Dual-Layer Nanostructured Flexible Thin-Film Amorphous Silicon Solar Cells with Enhanced Light Harvesting and Photoelectric Conversion Efficiency.

    Science.gov (United States)

    Lin, Yinyue; Xu, Zhen; Yu, Dongliang; Lu, Linfeng; Yin, Min; Tavakoli, Mohammad Mahdi; Chen, Xiaoyuan; Hao, Yuying; Fan, Zhiyong; Cui, Yanxia; Li, Dongdong

    2016-05-04

    Three-dimensional (3-D) structures have triggered tremendous interest for thin-film solar cells since they can dramatically reduce the material usage and incident light reflection. However, the high aspect ratio feature of some 3-D structures leads to deterioration of internal electric field and carrier collection capability, which reduces device power conversion efficiency (PCE). Here, we report high performance flexible thin-film amorphous silicon solar cells with a unique and effective light trapping scheme. In this device structure, a polymer nanopillar membrane is attached on top of a device, which benefits broadband and omnidirectional performances, and a 3-D nanostructure with shallow dent arrays underneath serves as a back reflector on flexible titanium (Ti) foil resulting in an increased optical path length by exciting hybrid optical modes. The efficient light management results in 42.7% and 41.7% remarkable improvements of short-circuit current density and overall efficiency, respectively. Meanwhile, an excellent flexibility has been achieved as PCE remains 97.6% of the initial efficiency even after 10 000 bending cycles. This unique device structure can also be duplicated for other flexible photovoltaic devices based on different active materials such as CdTe, Cu(In,Ga)Se2 (CIGS), organohalide lead perovskites, and so forth.

  19. Development of A Flexible System for the Simultaneous Conversion of Biomass to Industrial Chemicals and the Production of Industrial Biocatalysts

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Johnway; Hooker, Brian S.; Skeen, R S.; Anderson, D B.; Lankey, R. L.; Anastas, P. T.

    2002-01-01

    A flexible system was developed for the simultaneous conversion of biomass to industrial chemicals and the production of industrial biocatalysts. In particular, the expression of a bacterial enzyme, beta-glucuronidase (GUS), was investigated using a genetically modified starch-degrading Saccharomyces strain in suspension cultures in starch media. Different sources of starch including corn and waste potato starch were used for yeast biomass accumulation and GUS expression studies under controls of inducible and constitutive promoters. A thermostable bacterial cellulase, Acidothermus cellulolyticus E1 endoglucanase gene was also cloned into an episomal plasmid expression vector and expressed in the starch-degrading Saccharomyces strain.

  20. Polysiloxane Functionalized Carbon Dots and Their Cross-Linked Flexible Silicone Rubbers for Color Conversion and Encapsulation of White LEDs.

    Science.gov (United States)

    Wang, Yunfeng; Yin, Zhengmao; Xie, Zheng; Zhao, Xinxin; Zhou, Chuanjian; Zhou, Shuyun; Chen, Ping

    2016-04-20

    In this work, aminopropylmethylpolysiloxane (AMS) functionalized luminescent carbon dots (AMS-CDs) were prepared via a one-step solvothermal method. AMS-CDs could be self- or co-cross-linking with AMS to form 3D flexible transparent silicone rubbers (SRs) where CDs acted as cross-linking points, so the loading fraction of AMS-CDs could be adjusted from 10 to 100 wt %, thus modulating fluorescence properties and flexibility of silicone rubbers. Because of the self-curing property and high thermal stability, AMS-CDs were also studied in white LEDs (WLEDs), serving as a color conversion and encapsulation layer of GaN based blue LEDs simultaneously that would avoid the traditional problem of poor compatibility between emitting and packaging materials. And the color coordinate of AMS-CDs based WLEDs (0.33, 0.28) was very close to the pure white light. In addition, the obtained CDs cross-linked SRs had good transparency (T > 80%) at 510-1400 nm and high refractive indexes (1.33-1.54) that could meet the need of commercial packaging materials and optical application. AMS-CDs were also promising to be used in the UV LEDs based WLEDs according to their wide wavelength emission and flexible optoelectronic device.

  1. Toward Wearable Cooling Devices: Highly Flexible Electrocaloric Ba0.67 Sr0.33 TiO3 Nanowire Arrays.

    Science.gov (United States)

    Zhang, Guangzu; Zhang, Xiaoshan; Huang, Houbing; Wang, Jianjun; Li, Qi; Chen, Long-Qing; Wang, Qing

    2016-06-01

    Flexible lead-free ferroelectric ceramic nanowire arrays exhibit a unique combination of features that can contribute to the realization of wearable cooling devices, including an outstanding electrocaloric effect at low fields, high efficiency, bendability and stretchability, and robustness against mechanical deformations. Thermodynamic and phase-field simulations are carried out to validate their superior electrocaloric effect in comparison to thin films.

  2. High Temperature Fusion Reactor Cooling Using Brayton Cycle Based Partial Energy Conversion

    Science.gov (United States)

    Juhasz, Albert J.; Sawicki, Jerzy T.

    2003-01-01

    For some future space power systems using high temperature nuclear heat sources most of the output energy will be used in other than electrical form, and only a fraction of the total thermal energy generated will need to be converted to electrical work. The paper describes the conceptual design of such a partial energy conversion system, consisting of a high temperature fusion reactor operating in series with a high temperature radiator and in parallel with dual closed cycle gas turbine (CCGT) power systems, also referred to as closed Brayton cycle (CBC) systems, which are supplied with a fraction of the reactor thermal energy for conversion to electric power. Most of the fusion reactor's output is in the form of charged plasma which is expanded through a magnetic nozzle of the interplanetary propulsion system. Reactor heat energy is ducted to the high temperature series radiator utilizing the electric power generated to drive a helium gas circulation fan. In addition to discussing the thermodynamic aspects of the system design the authors include a brief overview of the gas turbine and fan rotor-dynamics and proposed bearing support technology along with performance characteristics of the three phase AC electric power generator and fan drive motor.

  3. Investigation of the Performance of D2O-Cooled High-Conversion Reactors for Fuel Cycle Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Hikaru Hiruta; Gilles Youinou

    2013-09-01

    This report presents FY13 activities for the analysis of D2O cooled tight-pitch High-Conversion PWRs (HCPWRs) with U-Pu and Th-U fueled cores aiming at break-even or near breeder conditions while retaining the negative void reactivity. The analyses are carried out from several aspects which could not be covered in FY12 activities. SCALE 6.1 code system is utilized, and a series of simple 3D fuel pin-cell models are developed in order to perform Monte Carlo based criticality and burnup calculations. The performance of U-Pu fueled cores with axial and internal blankets is analyzed in terms of their impact on the relative fissile Pu mass balance, initial Pu enrichment, and void coefficient. In FY12, Pu conversion performances of D2O-cooled HCPWRs fueled with MOX were evaluated with small sized axial/internal DU blankets (approximately 4cm of axial length) in order to ensure the negative void reactivity, which evidently limits the conversion performance of HCPWRs. In this fiscal year report, the axial sizes of DU blankets are extended up to 30 cm in order to evaluate the amount of DU necessary to reach break-even and/or breeding conditions. Several attempts are made in order to attain the milestone of the HCPWR designs (i.e., break-even condition and negative void reactivity) by modeling of HCPWRs under different conditions such as boiling of D2O coolant, MOX with different 235U enrichment, and different target burnups. A similar set of analyses are performed for Th-U fueled cores. Several promising characteristics of 233U over other fissile like 239Pu and 235U, most notably its higher fission neutrons per absorption in thermal and epithermal ranges combined with lower ___ in the fast range than 239Pu allows Th-U cores to be taller than MOX ones. Such an advantage results in 4% higher relative fissile mass balance than that of U-Pu fueled cores while retaining the negative void reactivity until the target burnup of 51 GWd/t. Several other distinctions between U-Pu and

  4. Neutron conversion and cascaded cooling in paramagnetic systems for a high-flux source of very cold neutrons

    Science.gov (United States)

    Zimmer, Oliver

    2016-03-01

    A new neutron-cooling mechanism is proposed with potential benefits for novel intense sources of very cold neutrons with wavelengths >2 nm, and for enhancing the production of ultracold neutrons. It employs inelastic magnetic scattering in weakly absorbing, cold paramagnetic systems. Kinetic energy is removed from the neutron stepwise in constant decrements determined by the Zeeman energy of paramagnetic atoms or ions in an external magnetic field, or by zero-field level splittings in magnetic molecules. The stationary neutron transport equation is analyzed for an infinite, homogeneous medium with Maxwellian neutron sources, using inelastic scattering cross sections derived in an appendix. Nonmagnetic inelastic scattering processes are neglected. The solution therefore still underestimates very cold neutron densities that should be achievable in a real medium. Molecular oxygen with its triplet ground state appears particularly promising, notably as a host in fully deuterated O2-clathrate hydrate. Other possibilities are dry O2-4He van der Waals clusters and O2 intercalated in fcc-C60. For conversion of cold to ultracold neutrons, where an incident neutron imparts only a single energy quantum to the medium, the paramagnetic scattering in the clathrate system is found to be stronger, by more than an order of magnitude, than the single-phonon emission in superfluid helium, when evaluated for an incident neutron spectrum with the optimum temperature for the respective medium. Moreover, the multistep paramagnetic cooling cascade leads to further strong enhancements of very cold neutron densities, e.g., by a factor 14 (57) for an initial neutron temperature of 30 K (100 K ), for the moderator held at about 1.3 K . Due to a favorable Bragg cutoff of the O2 clathrate, the cascade-cooling can take effect in a moderator with linear extensions smaller than a meter.

  5. Thickness ratio and d 33 effects on flexible piezoelectric unimorph energy conversion

    Science.gov (United States)

    Ha, Taewoo; Zhang, John X. J.; Lu, Nanshu

    2016-03-01

    Piezoelectric unimorphs are bilayer structures where a blanket piezoelectric film (with top and bottom electrodes) is uniformly laminated on an inactive but flexible substrate. Because of their simple construction and flexibility, unimorphs are widely used as a key element in flexible sensors and actuators. The response of a unimorph is governed by the material properties of the film and the substrate as well as their geometric parameters. For low frequency biological energy harvesting, structural optimization is critical due to the dimensional confinement imposed by curvilinear and deformable bio-tissues. Here we report a comprehensive theoretical framework to investigate the effects of the film-to-substrate thickness ratio on voltage, charge, and energy outputs when the unimorph is subjected to eight different boundary/loading conditions. A broad class of power generators can be designed using such a framework under the assumption that the unimorph length is very large compared to its thickness, where the only dimensionless variable is the film-to-substrate thickness ratio. We show that the analytical and finite element modeling results are in excellent agreement. For not so thin unimorphs, there is non-zero normal stress in the thickness direction (σ 3) and d 33 can play a significant role in this case. Non-monotonic dependence of voltage and energy generation on thickness ratio has been found in some cases and optimum thickness ratio for unimorph generator can be predicted. When the unimorph is actuated by voltage applied across the piezo-film thickness, non-monotonic maximum deflection versus thickness ratio is also found. This work provides new physical insights on unimorphs and analytical solutions that can be used for the structural design and optimization of unimorphs under different boundary/loading conditions.

  6. Design methodology for flexible energy conversion systems accounting for dynamic performance

    DEFF Research Database (Denmark)

    Pierobon, Leonardo; Casati, Emiliano; Casella, Francesco

    2014-01-01

    This article presents a methodology to help in the definition of the optimal design of power generation systems. The innovative element is the integration of requirements on dynamic performance into the system design procedure. Operational flexibility is an increasingly important specification...... of these simulations are used within the framework of a multi-objective optimization procedure to identify a number of equally optimal system configurations. A dynamic model of each of these systems is automatically parameterized, by inheriting its parameters values from the design model. Dynamic simulations allow...

  7. Preliminary Neutronics Design and Analysis of D2O Cooled High Conversion PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Hikaru Hiruta; Gilles Youinou

    2012-09-01

    This report presents a neutronics analysis of tight-pitch D2O-cooled PWRs loaded with MOX fuel and focuses essentially on the Pu breeding potential of such reactors as well as on an important safety parameter, the void coefficient, which has to be negative. It is well known that fast reactors have a better neutron economy and are better suited than thermal reactors to breed fissile material from neutron capture in fertile material. Such fast reactors (e.g. sodium-cooled reactors) usually rely on technologies that are very different from those of existing water-cooled reactors and are probably more expensive. This report investigates another possibility to obtain a fast neutron reactor while still relying mostly on a PWR technology by: (1) Tightening the lattice pitch to reduce the water-to-fuel volume ratio compared to that of a standard PWR. Water-to-fuel volume ratios of between 0.45 and 1 have been considered in this study while a value of about 2 is typical of standard PWRs, (2) Using D2O instead of H2O as a coolant. Indeed, because of its different neutron physics properties, the use of D2O hardens the neutron spectrum to an extent impossible with H2O when used in a tight-pitch lattice. The neutron spectra thus obtained are not as fast as those in sodium-cooled reactor but they can still be characterized as fast compared to that of standard PWR neutron spectra. In the phase space investigated in this study we did not find any configurations that would have, at the same time, a positive Pu mass balance (more Pu at the end than at the beginning of the irradiation) and a negative void coefficient. At this stage, the use of radial blankets has only been briefly addressed whereas the impact of axial blankets has been well defined. For example, with a D2O-to-fuel volume ratio of 0.45 and a core driver height of about 60 cm, the fissile Pu mass balance between the fresh fuel and the irradiated fuel (50 GWd/t) would be about -7.5% (i.e. there are 7.5% fewer fissile Pu

  8. Conversation Salons: A Flexible Format for Open Discourse in Dental Education.

    Science.gov (United States)

    Quick, Karin K

    2016-04-01

    A series of conversation salons was created at the University of Minnesota School of Dentistry as an innovative format with the objective of engaging students, faculty, staff, and practitioners in discussion to promote reflection. The aim of this study was to explore the nature of students' abilities in the salons to connect experiences through reflection and apply what they learned to practice. Reflective essays (written during the summer and fall semesters of 2014) from 108 fourth-year dental students (all members of the Class of 2015) were read and assessed for the nature of reflection, number of connections, references to the past, applications to the future, and use of examples. For analysis, the theoretical works of Schön and Mezirow provided a useful framework. Overall, the results showed that the participants found the salon experience to be positive, and student participation was strong. When asked about learning, the most frequent responses were topic-related. At this stage of dental education, the students were largely focused on their future practice and found it easier to connect to an imagined future than a past experience. In terms of student abilities to reflect, the majority were skilled at simple reflection, based on these essays since only 18% were non-reflective and 15% showed strong critical reflection skills. The open and respectful environment of the salons enabled discussion and promoted reflection. These results suggest that more opportunities for collegial conversations and instruction in reflective practice earlier in the dental curriculum may be beneficial.

  9. Flexible Residential Test Facility: Impact of Infiltration and Ventilation on Measured Cooling Season Energy and Moisture Levels

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Danny S. [BA-PIRC/Florida Solar Energy Center, Cocoa, FL (United States); Cummings, Jamie E. [BA-PIRC/Florida Solar Energy Center, Cocoa, FL (United States); Vieira, Robin K. [BA-PIRC/Florida Solar Energy Center, Cocoa, FL (United States); Fairey, III, Phillip W. [BA-PIRC/Florida Solar Energy Center, Cocoa, FL (United States); Sherwin, John S. [BA-PIRC/Florida Solar Energy Center, Cocoa, FL (United States); Withers, Jr., Charles [BA-PIRC/Florida Solar Energy Center, Cocoa, FL (United States); Hoak, David [BA-PIRC/Florida Solar Energy Center, Cocoa, FL (United States); Beal, David [BA-PIRC/Florida Solar Energy Center, Cocoa, FL (United States)

    2016-09-01

    Air infiltration and ventilation in residential buildings is a very large part of the heating loads, but empirical data regarding the impact on space cooling has been lacking. Moreover, there has been little data on how building tightness might relate to building interior moisture levels in homes in a hot and humid climate. To address this need, BA-PIRC has conducted research to assess the moisture and cooling load impacts of airtightness and mechanical ventilation in two identical laboratory homes in the hot-humid climate over the cooling season.

  10. Flexible Residential Test Facility: Impact of Infiltration and Ventilation on Measured Cooling Season Energy and Moisture Levels

    Energy Technology Data Exchange (ETDEWEB)

    Parker, D.; Kono, J.; Vieira, R.; Fairey, P.; Sherwin, J.; Withers, C.; Hoak, D.; Beal, D.

    2014-05-01

    Air infiltration and ventilation in residential buildings is a very large part of the heating loads, but empirical data regarding the impact on space cooling has been lacking. Moreover, there has been little data on how building tightness might relate to building interior moisture levels in homes in a hot and humid climate. To address this need, BA-PIRC has conducted research to assess the moisture and cooling load impacts of airtightness and mechanical ventilation in two identical laboratory homes in the hot-humid climate over the cooling season.

  11. Transient Load Following and Control Analysis of Advanced S-CO2 Power Conversion with Dry Air Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Moisseytsev, Anton; Sienicki, James J.

    2016-01-01

    Supercritical carbon dioxide (S-CO2) Brayton cycles are under development as advanced energy converters for advanced nuclear reactors, especially the Sodium-Cooled Fast Reactor (SFR). The use of dry air cooling for direct heat rejection to the atmosphere ultimate heat sink is increasingly becoming a requirement in many regions due to restrictions on water use. The transient load following and control behavior of an SFR with an S-CO2 cycle power converter utilizing dry air cooling have been investigated. With extension and adjustment of the previously existing control strategy for direct water cooling, S-CO2 cycle power converters can also be used for load following operation in regions where dry air cooling is a requirement

  12. Technical use of solar energy: Conversion from solar to thermal energy, solar cooling and thermal energy storage

    Science.gov (United States)

    Arafa, A.; Fisch, N.; Hahne, E.; Kraus, K.; Seemann, D.; Seifert, B.; Sohns, J.; Schetter, G.; Schweigerer, W.

    1983-12-01

    Experimental and theoretical studies in the field of solar energy utilization are reviewed. Specific topics considered are: flat plate water collectors, solar absorbers, air collectors, solar absorption cooling, solar simulators, aquifiers, latent heat stores, and space heating systems.

  13. A Three-Level Quasi-Two-Stage Single-Phase PFC Converter with Flexible Output Voltage and Improved Conversion Efficiency

    DEFF Research Database (Denmark)

    Tang, Yi; Zhu, Dexuan; Jin, Chi

    2015-01-01

    voltage will be fairly constant. The dynamic response of this regulation loop is also very fast and the system is therefore insensitive to external disturbances. Both simulation and experimental results are presented to show the effectiveness of this converter as well as its efficiency improvement against......This paper presents a three-level quasi-two-stage single-phase power factor correction (PFC) converter that has flexible output voltage and improved conversion efficiency. The proposed PFC converter features sinusoidal input current, three-level output characteristic, and a wide range of output dc...... voltages, and it will be very suitable for high-power applications where the output voltage can be either lower or higher than the peak ac input voltage, e.g., plug-in hybrid electric vehicle charging systems. Moreover, the involved dc/dc buck conversion stage may only need to process partial input power...

  14. Evaluation of Variable Refrigerant Flow Systems Performance on Oak Ridge National Laboratory s Flexible Research Platform: Part 1 Cooling Season Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Im, Piljae [ORNL; Malhotra, Mini [ORNL; Munk, Jeffrey D [ORNL

    2016-08-01

    This report provides second-year cooling season test results for the multi-year project titled “Evaluation of Variable Refrigeration Flow (VRF) System on Oak Ridge National Laboratory (ORNL)’s Flexible Research Platform (FRP).” The purpose of the second-year project was to (1) evaluate the full- and partload performance of VRF systems compared with an existing baseline heating, ventilation, and airconditioning (HVAC) system, which is a conventional rooftop unit (RTU) variable-air-volume (VAV) system with electric resistance heating and (2) use hourly building energy simulation to evaluate the energy savings potential of using VRF systems in major US cities. The second-year project performance period was from July 2015 through June 2016.

  15. A Flexible, Stretchable and Shape-Adaptive Approach for Versatile Energy Conversion and Self-Powered Biomedical Monitoring

    KAUST Repository

    Yang, Po Kang

    2015-05-15

    A flexible triboelectric nanogenerator (FTENG) based on wavy-structured Kapton film and a serpentine electrode on stretchable substrates is presented. The as-fabricated FTENG is capable of harvesting ambient mechanical energy via both compressive and stretching modes. Moreover, the FTENG can be a bendable power source to work on curved surfaces; it can also be adaptively attached onto human skin for monitoring gentle body motions. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Optimization of an Electron Transport Layer to Enhance the Power Conversion Efficiency of Flexible Inverted Organic Solar Cells

    Directory of Open Access Journals (Sweden)

    Lee Kang Hyuck

    2010-01-01

    Full Text Available Abstract The photovoltaic (PV performance of flexible inverted organic solar cells (IOSCs with an active layer consisting of a blend of poly(3-hexylthiophene and [6, 6]-phenyl C61-butlyric acid methyl ester was investigated by varying the thicknesses of ZnO seed layers and introducing ZnO nanorods (NRs. A ZnO seed layer or ZnO NRs grown on the seed layer were used as an electron transport layer and pathway to optimize PV performance. ZnO seed layers were deposited using spin coating at 3,000 rpm for 30 s onto indium tin oxide (ITO-coated polyethersulphone (PES substrates. The ZnO NRs were grown using an aqueous solution method at a low temperature (90°C. The optimized device with ZnO NRs exhibited a threefold increase in PV performance compared with that of a device consisting of a ZnO seed layer without ZnO NRs. Flexible IOSCs fabricated using ZnO NRs with improved PV performance may pave the way for the development of PV devices with larger interface areas for effective exciton dissociation and continuous carrier transport paths.

  17. Flexible Dielectric Nanocomposites with Ultrawide Zero-Temperature Coefficient Windows for Electrical Energy Storage and Conversion under Extreme Conditions.

    Science.gov (United States)

    Shehzad, Khurram; Xu, Yang; Gao, Chao; Li, Hanying; Dang, Zhi-Min; Hasan, Tawfique; Luo, Jack; Duan, Xiangfeng

    2017-03-01

    Polymer dielectrics offer key advantages over their ceramic counterparts such as flexibility, scalability, low cost, and high breakdown voltages. However, a major drawback that limits more widespread application of polymer dielectrics is their temperature-dependent dielectric properties. Achieving dielectric constants with low/zero-temperature coefficient (L/0TC) over a broad temperature range is essential for applications in diverse technologies. Here, we report a hybrid filler strategy to produce polymer composites with an ultrawide L/0TC window of dielectric constant, as well as a significantly enhanced dielectric value, maximum energy storage density, thermal conductivity, and stability. By creating a series of percolative polymer composites, we demonstrated hybrid carbon filler based composites can exhibit a zero-temperature coefficient window of 200 °C (from -50 to 150 °C), the widest 0TC window for all polymer composite dielectrics reported to date. We further show the electric and dielectric temperature coefficient of the composites is highly stable against stretching and bending, even under AC electric field with frequency up to 1 MHz. We envision that our method will push the functional limits of polymer dielectrics for flexible electronics in extreme conditions such as in hybrid vehicles, aerospace, power electronics, and oil/gas exploration.

  18. Roll-coating fabrication of flexible large area small molecule solar cells with power conversion efficiency exceeding 1%

    DEFF Research Database (Denmark)

    Liu, Wenqing; Liu, Shiyong; Zawacka, Natalia Klaudia

    2014-01-01

    All solution-processed flexible large area small molecule bulk heterojunction solar cells were fabricated via roll-coating technology. Our devices were produced from slot-die coating on a lab-scale mini roll-coater under ambient conditions without the use of spin-coating or vacuum evaporation.......01%, combined with an open circuit voltage of 0.73 V, a short-circuit current density of 3.13 mA cm (2) and a fill factor of 44% were obtained for the device with SM1, which was the first example reported for efficient roll-coating fabrication of flexible large area small molecule solar cells with PCE exceeding...... 1%. In addition, rollcoated devices based on SMs 2-4 also showed good performances with PCEs of 0.41%, 0.54%, and 0.31%, respectively. Our results prove that small molecules have the potential for use in industries for large scale production of efficient organic solar cells....

  19. Optimization of an Electron Transport Layer to Enhance the Power Conversion Efficiency of Flexible Inverted Organic Solar Cells.

    Science.gov (United States)

    Lee, Kang Hyuck; Kumar, Brijesh; Park, Hye-Jeong; Kim, Sang-Woo

    2010-08-31

    The photovoltaic (PV) performance of flexible inverted organic solar cells (IOSCs) with an active layer consisting of a blend of poly(3-hexylthiophene) and [6, 6]-phenyl C(61)-butlyric acid methyl ester was investigated by varying the thicknesses of ZnO seed layers and introducing ZnO nanorods (NRs). A ZnO seed layer or ZnO NRs grown on the seed layer were used as an electron transport layer and pathway to optimize PV performance. ZnO seed layers were deposited using spin coating at 3,000 rpm for 30 s onto indium tin oxide (ITO)-coated polyethersulphone (PES) substrates. The ZnO NRs were grown using an aqueous solution method at a low temperature (90°C). The optimized device with ZnO NRs exhibited a threefold increase in PV performance compared with that of a device consisting of a ZnO seed layer without ZnO NRs. Flexible IOSCs fabricated using ZnO NRs with improved PV performance may pave the way for the development of PV devices with larger interface areas for effective exciton dissociation and continuous carrier transport paths.

  20. Design of Hydraulic Generator Cooling Fan Frequency Conversion Control System%水轮发电机冷却风机变频控制系统的设计

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      讲述基于PLC的PID控制算法的水轮发电机冷却风机变频控制系统。系统主要应用于灯泡贯流式水轮发电机组,使得灯泡贯流机组冷却温度恰当,既节能又兼顾发电效率和发电机寿命。%This paper describes the PID control algorithm of PLC based turbine generator cooling fan frequency conversion control system. The system is mainly used for bulb turbine unit,the bulb tubular units appropriate cooling temperature,energy saving,power generation efficiency and service life of the generator.

  1. Flexible 'zoning' aids adaptability.

    Science.gov (United States)

    Corben, Simon

    2013-09-01

    Simon Corben, business development director at Capita Symonds' Health team, examines how 'clever use of zoning' when planning new healthcare facilities could improve hospital design, increase inherent flexibility, and reduce lifetime costs, and argues that a 'loose-fit, non-bespoke approach' to space planning will lead to 'more flexible buildings that are suitable for conversion to alternative uses'.

  2. Determining the Optimal Capacities of Renewable-Energy-Based Energy Conversion Systems for Meeting the Demands of Low-Energy District Heating, Electricity, and District Cooling

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend; Dincer, Ibrahim

    2015-01-01

    This chapter presents a method for determining the optimal capacity of a renewable-energy-based energy conversion system for meeting the energy requirements of a given district as considered on a monthly basis, with use of a low-energy district heating system operating at a low temperature, as lo...

  3. The Mercury Laser System: An Average power, gas-cooled, Yb:S-FAP based system with frequency conversion and wavefront correction

    Energy Technology Data Exchange (ETDEWEB)

    Bibeau, C; Bayramian, A; Armstrong, P; Ault, E; Beach, R; Benapfl, M; Campbell, R; Dawson, J; Ebbers, C; Freitas, B; Kent, R; Liao, Z; Ladran, T; Menapace, J; Molander, B; Moses, E; Oberhelman, S; Payne, S; Peterson, N; Schaffers, K; Stolz, C; Sutton, S; Tassano, J; Telford, S; Utterback, E; Randles, M

    2005-08-31

    We report on the operation of the Mercury laser with fourteen 4 x 6 cm{sup 2} Yb:S-FAP amplifier slabs pumped by eight 100 kW peak power diode arrays. The system was continuously run at 55 J and 10 Hz for several hours, (2 x 10{sup 5} cumulative shots) with over 80% of the energy in a 6 times diffraction limited spot at 1.047 um. Improved optical quality was achieved in Yb:S-FAP amplifiers with magneto-rheological finishing, a deterministic polishing method. In addition, average power frequency conversion employing YCOB was demonstrated at 50% conversion efficiency or 22.6 J at 10 Hz.

  4. Electron cooling

    Science.gov (United States)

    Meshkov, I.; Sidorin, A.

    2004-10-01

    The brief review of the most significant and interesting achievements in electron cooling method, which took place during last two years, is presented. The description of the electron cooling facilities-storage rings and traps being in operation or under development-is given. The applications of the electron cooling method are considered. The following modern fields of the method development are discussed: crystalline beam formation, expansion into middle and high energy electron cooling (the Fermilab Recycler Electron Cooler, the BNL cooler-recuperator, cooling with circulating electron beam, the GSI project), electron cooling in traps, antihydrogen generation, electron cooling of positrons (the LEPTA project).

  5. Application of SrAl2O4:Eu2+ Down-conversion Powder in Flexible Dye-Sensitized Solar Cells

    Institute of Scientific and Technical Information of China (English)

    WANG Lijun; HU Zhiqiang; LI Yueying; HAO Hongshun; GUO Weihua; SU Qing; JIN Shanshan; QIN Lei; GAO Wenyuan; LIU Guishan

    2015-01-01

    TiO2 nanotube (NT) was firstly prepared on titanium foil by an electrochemical anodization method, and then modifiedvia subsequent deposition of a layer of SrAl2O4:Eu2+ phosphor embedded within TiO2 nanoparticles to fabri-cate photoanodes of dye–sensitized solar cells (DSSCs). The effect of doping down–conversion SrAl2O4:Eu2+ phosphor in DSSCs was investigated. SrAl2O4:Eu2+ can effectively convert ultraviolet light to visible light within the range of the dye commonly used in DSSC to increase the photocurrent of DSSC, and enhance the open–circuit voltage by ap–type doping effect. When the ratio of SrAl2O4:Eu2+ in the doping layer is optimized to be 1wt.%, the photoelectric conversion efficiency of the DSSC reaches 3.09%, which is increased by 38.6%, compared to that of the DSSC without SrAl2O4:Eu2+ doping.

  6. Application of SrAl2O4:Eu2+ Down–conversion Powder in Flexible Dye–Sensitized Solar Cells

    Institute of Scientific and Technical Information of China (English)

    WANG; Lijun; LI; Yueying; HAO; Hongshun; GUO; Weihua; SU; Qing; JIN; Shanshan; QIN; Lei; GAO; Wenyuan; LIU; Guishan; HU; Zhiqiang

    2015-01-01

    TiO2 nanotube(NT) was firstly prepared on titanium foil by an electrochemical anodization method, and then modified via subsequent deposition of a layer of SrAl2O4:Eu2+ phosphor embedded within TiO2 nanoparticles to fabricate photoanodes of dye–sensitized solar cells(DSSCs). The effect of doping down–conversion Sr Al2O4:Eu2+ phosphor in DSSCs was investigated. SrAl2O4:Eu2+ can effectively convert ultraviolet light to visible light within the range of the dye commonly used in DSSC to increase the photocurrent of DSSC, and enhance the open–circuit voltage by a p–type doping effect. When the ratio of Sr Al2O4:Eu2+ in the doping layer is optimized to be 1wt.%, the photoelectric conversion efficiency of the DSSC reaches 3.09%, which is increased by 38.6%, compared to that of the DSSC without Sr Al2O4:Eu2+ doping.

  7. Graphene composite for improvement in the conversion efficiency of flexible poly 3-hexyl-thiophene:[6,6]-phenyl C{sub 71} butyric acid methyl ester polymer solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Chauhan, A. K., E-mail: akchau@barc.gov.in, E-mail: akc.barc@gmail.com; Gusain, Abhay; Jha, P.; Koiry, S. P.; Saxena, Vibha; Veerender, P.; Aswal, D. K.; Gupta, S. K. [Technical Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085 (India)

    2014-03-31

    The solution of thin graphene-sheets obtained from a simple ultrasonic exfoliation process was found to chemically interact with [6,6]-phenyl C{sub 71} butyric acid methyl ester (PCBM) molecules. The thinner graphene-sheets have significantly altered the positions of highest occupied molecular orbital and lowest unoccupied molecular orbital of PCBM, which is beneficial for the enhancement of the open circuit voltage of the solar cells. Flexible bulk heterojunction solar cells fabricated using poly 3-hexylthiophene (P3HT):PCBM-graphene exhibited a power conversion efficiency of 2.51%, which is a ∼2-fold increase as compared to those fabricated using P3HT:PCBM. Inclusion of graphene-sheets not only improved the open-circuit voltage but also enhanced the short-circuit current density owing to an improved electron transport.

  8. Stochastic Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Blaskiewicz, M.

    2011-01-01

    Stochastic Cooling was invented by Simon van der Meer and was demonstrated at the CERN ISR and ICE (Initial Cooling Experiment). Operational systems were developed at Fermilab and CERN. A complete theory of cooling of unbunched beams was developed, and was applied at CERN and Fermilab. Several new and existing rings employ coasting beam cooling. Bunched beam cooling was demonstrated in ICE and has been observed in several rings designed for coasting beam cooling. High energy bunched beams have proven more difficult. Signal suppression was achieved in the Tevatron, though operational cooling was not pursued at Fermilab. Longitudinal cooling was achieved in the RHIC collider. More recently a vertical cooling system in RHIC cooled both transverse dimensions via betatron coupling.

  9. Analysis on hydrodynamic performances of a tidal current energy conversion device-flexible vane turbine%潮流能柔性叶片水轮机水动力学特性分析

    Institute of Scientific and Technical Information of China (English)

    王树杰; 李华军; 李冬; 鹿兰帅; 单忠德; 赵龙武

    2009-01-01

    The paper puts forward a new type of marine current energy conversion device, a flexible vane turbine. Its flexible vane is made of flexible material, which can deform to adapt to fluid. Thus the turbine can adjust the attack angle automatically to take full advantage of the lift effect and drag effect and produce as more power as possible, so it has unique hydrodynamic performances. Focusing on the power efficiency coefficient ( C_p ) , the authors studied its hydrodynamic characteristics and the affecting factors on them via a model test in a water tank. The results proved its characteristics and showed that, the shape of flexible vane and the structure of turbine rotor are the main factors affecting on its performance. Based on the analysis of the results, an optimal scheme of the flexible vane turbine having higher coefficient of power was proposed.%提出了一种新型海洋潮流能获取装置--潮流能柔性叶片水轮机.其叶片采用柔性材料,可适应流体发生形变,从而它能自动调节攻角,能充分利用流体的升力效应和阻力效应做功,具有独特的水动力学特性.以柔性叶片水轮机获能系数(C_p)为主要研究目标,通过水槽模型实验对其影响因素进行了研究.实验证实了该柔性叶片水轮机的独特水动力学特性,而且证明,叶片形状和水轮机结构形式是其性能的主要影响因素,并通过分析得到了具有较佳水动力学特性的水轮机的叶片形状和水轮机结构形式.

  10. Preliminary studies on the heat exchanger option for S-CO{sub 2} power conversion cycle coupled to water cooled SMR

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Y.; Lee, J. [Dept. of Nuclear and Quantum Engineering, Korea Advanced Inst. of Science and Technology, 373-1 Guseong-dong Yuseong-gu, Daejeon, 305-701 (Korea, Republic of); Lee, J. I. [Dept. of Nuclear and Quantum Engineering, Korea Advanced Inst. of Science and Technology, 373-1 Guseong-dong Yuseong-gu, Daejeon, 305-701 (Korea, Republic of); Dept. of Nuclear Engineering, Khalifa Univ. of Science, Technology and Research (KUSTAR), P.O.Box 127788, Abu Dhabi (United Arab Emirates)

    2012-07-01

    For more than a half century, the steam Rankine cycle had been the major power conversion cycle for a nuclear power plant. However, as the interest on the next generation reactors grows, a variety of alternative power conversion systems have been studied. Among them, the S-CO{sub 2} cycle (Supercritical carbon dioxide Brayton cycle) is considered as a promising candidate due to several benefits such as 1) Relatively high thermal efficiency at relatively low turbine inlet temperature, 2) High efficiency with simple lay-out 3) Compactness of turbo-machineries. 4) Compactness of total cycle combined with PCHE (Printed Circuit Heat Exchanger). According to the conventional classification of heat exchangers (HE), there are three kind of HE, 1) Tubular HEs, 2) Plate-type HEs, 3) Extended surface HEs. So far, the researcher has mostly assumed PCHE type HE for the S-CO{sub 2} cycle due to its compactness with reasonably low pressure drop. However, PCHE is currently one of the most expensive components in the cycle, which can have a negative effect on the economics of the cycle. Therefore, an alternative for the HE should be seriously investigated. By comparing the operating condition (pressure and temperature) there are three kind of HE in the S-CO{sub 2} cycle, 1) IHX (Intermediate Heat exchanger) 2) Recuperator and 3) Pre-cooler. In each heat exchanger, hot side and cold side coolants are different, i.e. reactor coolant to S-CO{sub 2} (IHX), S-CO{sub 2} to S-CO{sub 2}(Recuperator), S-CO{sub 2} to water (Pre-cooler). By considering all the attributes mentioned above, all existing types of heat exchangers are compared to find a possible alternative to PCHE. The comparing factors are 1) Size(volume), 2) Cost. Plate fin type HEs are considered to be the most competitive heat exchanger regarding the size and the cost after some improvements on the design limit are made. (authors)

  11. Flexible Flatfoot

    Science.gov (United States)

    ... this page. Please enable Javascript in your browser. Flexible Flatfoot What Is Flatfoot? Flatfoot is often a ... may develop as a result of a flatfoot. Flexible Flatfoot Flexible flatfoot is one of the most ...

  12. Frequency Conversion Activation on the Mercury Laser

    Energy Technology Data Exchange (ETDEWEB)

    Bayramian, A J; Beach, R J; Bibeau, C; Campbell, R; Ebbers, C A; Freitas, B L; Kent, R; Van Lue, D; Liao, Z; Landron, T; Payne, S A; Schaffers, K I; Sutton, S; Fei, Y; Chai, B

    2004-09-24

    High efficiency frequency conversion while operating at average power is critical for the Mercury laser. We will demonstrate average power frequency conversion of face-cooled DKDP and YCOB crystals using a sapphire heat spreader approach.

  13. Investigations on an oriented cooling design for thermoelectric cogenerations

    Science.gov (United States)

    Zheng, X. F.; Liu, C. X.; Yan, Y. Y.

    2012-11-01

    In thermoelectric application, it is widely known that the material limitation has still been the chief barrier of lifting its application to a higher level. Continuous efforts are extensively being made in developing novel material structures and constructions for thermoelectric modules with higher conversion efficiency. However, the overall system efficiency, which is one of the major parameters that most of the engineer and users care about, is not only ruled by the properties of applied thermoelectric materials, but also decided by the design of heat exchangers used on both sides of thermoelectric modules. Focusing on the cooling capacity and hydraulic characteristics of heat exchanger, this paper introduces an oriented cooling method for the domestic thermoelectric cogeneration, which delivers system efficiency up to 80%. This purpose-oriented cooling plate is designed for thermoelectric cogeneration for the residential houses installed with boiler or other heating facilities with a considerable amount of unused heat. The design enables Thermoelectric Cogeneration System (TCS) to be flexibly integrated into the existing hydraulic system. The mathematical model for the cooling plate has been established for a well understanding at the theoretical level. The performance of cooling plate has been investigated in a series of experimental studies which have been conducted under different coolant inlet velocity and temperature. The economic operating zone in which a good system performance could be achieved has been discussed and identified for the current configuration.

  14. Influência do resfriamento e do aquecimento local na flexibilidade dos músculos isquiotibiais Influence of local cooling and warming on the flexibility of the hamstring muscles

    Directory of Open Access Journals (Sweden)

    JS Brasileiro

    2007-02-01

    Full Text Available OBJETIVO: O propósito deste estudo foi analisar os efeitos do resfriamento e do aquecimento sobre a flexibilidade dos músculos isquiotibiais, observando os efeitos agudos e crônicos. MÉTODOS: Quarenta voluntários foram aleatoriamente incluídos em um dos quatro grupos (n=10: 1 grupo controle; 2 grupo alongamento (técnica sustentar-relaxar para os músculos isquiotibiais, por duas semanas consecutivas; 3 grupo alongamento precedido da aplicação de crioterapia (25 minutos na região posterior da coxa e 4 grupo alongamento precedido de aquecimento com diatermia por ondas curtas (25 minutos. A avaliação da flexibilidade muscular foi realizada através de uma prancha acoplada a um sistema de goniometria, especialmente preparada para avaliar o ângulo extensor do joelho. RESULTADOS: Os três grupos experimentais aumentaram significativamente a ADM em relação ao grupo controle. Os ganhos médios diários, considerados efeitos agudos, mostraram diferenças significativas em favor do grupo submetido ao resfriamento, quando comparado aos demais (aumento de 2,6 ± 0,9°, 4,3 ± 1,5° e 2,4 ± 0,7° para os grupos 2, 3 e 4, respectivamente, p= 0,008. Em relação aos efeitos crônicos, não foi observada diferença significativa entre os três grupos experimentais, embora todos diferiram do controle (aumento de 1,5 ± 0,5°, 11,1 ± 6,1°, 14,4 ± 5,4° e 14,4 ± 6,2°, para os grupos 1, 2, 3 e 4, respectivamente. CONCLUSÕES: Sessões de alongamento, aplicadas diariamente, aumentaram significativamente a flexibilidade dos músculos isquiotibiais. Os efeitos agudos foram maiores no grupo submetido ao resfriamento, quando comparado aos grupos somente alongado ou aquecido. Os efeitos crônicos não foram influenciados pelo aquecimento nem pelo resfriamento.OBJECTIVE: The aim of this study was to analyze the acute and chronic effects of cooling and warming on hamstring muscle flexibility. METHOD: Forty volunteers were randomly included in one of

  15. Ifp's New Flexible Hydrocracking Process Combines Maximum Conversion with Production of High Viscosity, High Vi Lube Stocks Le nouveau procédé IFP d'hydrocraquage à haute flexibilité combine conversion maximum et production de bases, huile à haute viscosité et à indice de viscosité élevé

    Directory of Open Access Journals (Sweden)

    Hennico A.

    2006-11-01

    Full Text Available Institut Français du Pétrole (IFP has developed a new dual catalytic system for its hydrocracking process that enables high conversion to middle distillates and production of high viscosity, high VI lube stocks. Although the hydrocracking process is mainly devoted to the conversion of vacuum distillates, deasphalted oil or mixture of both into high quality middle distillates, it can also produce a residue, that after dewaxing will be a very high VI lube base oil. In this presentation major emphasis is put on the possibility to produce very high VI lubes with high viscosity thanks to the development of the new catalytic system. Large flexibility in feedstock selection and easy control of operating variables allow the production of all grades of lube oils associated with high quality middle distillates for a large range of conversion levels. L'Institut Français du Pétrole (IFP a mis au point, pour son procédé d'hydrocraquage, un nouveau système catalytique à 2 catalyseurs qui permet une forte conversion en distillats moyens et la production de fractions lubrifiantes à haute viscosité et indice de viscosité élevé. Si le procédé d'hydrocraquage est essentiellement utilisé pour la conversion de distillats sous vide, d'huile désasphaltée ou d'un mélange des deux en distillats moyens de haute qualité, il peut aussi produire un résidu qui, après déparaffinage, fournira une base pour lubrifiant à indice de viscosité très élevé. Cet article souligne particulièrement la possibilité de produire des lubrifiants à indice de viscosité très élevé et haute viscosité, grâce à ce nouveau système catalytique. Une grande flexibilité dans le choix des produits à traiter et la facilité de contrôle des paramètres opératoires permet la production de toutes les qualités d'huiles lubrifiantes associées à des distillats moyens de haute qualité, pour une large gamme de niveaux de conversion.

  16. Flexible supercapacitors

    Institute of Scientific and Technical Information of China (English)

    Shan Shi; Chengjun Xu; Cheng Yang; Jia Li; Hongda Du; Baohua Li; Feiyu Kang

    2013-01-01

    Flexible supercapacitors show a great potential for applications in wearable,miniaturized,portable,largescale transparent and flexible consumer electronics due to their significant,inherent advantages,such as being flexible,lightweight,low cost and environmentally friendly in comparison with the current energy storage devices.In this report,recent progress on flexible supercapacitors,flexible electrodes and electrolytes is reviewed.In addition,the future challenges and opportunities are discussed.

  17. Wavelength conversion technology

    DEFF Research Database (Denmark)

    Stubkjær, Kristian

    1998-01-01

    Optical wavelength conversion is currently attracting much interest. This is because it enables full flexibility and eases management of WDM fibre networks. The tutorial will review existing and potential application areas. Examples of node architectures and network demonstrators that use wavelen...

  18. High-performance and flexible thermoelectric films by screen printing solution-processed nanoplate crystals

    Science.gov (United States)

    Varghese, Tony; Hollar, Courtney; Richardson, Joseph; Kempf, Nicholas; Han, Chao; Gamarachchi, Pasindu; Estrada, David; Mehta, Rutvik J.; Zhang, Yanliang

    2016-09-01

    Screen printing allows for direct conversion of thermoelectric nanocrystals into flexible energy harvesters and coolers. However, obtaining flexible thermoelectric materials with high figure of merit ZT through printing is an exacting challenge due to the difficulties to synthesize high-performance thermoelectric inks and the poor density and electrical conductivity of the printed films. Here, we demonstrate high-performance flexible films and devices by screen printing bismuth telluride based nanocrystal inks synthesized using a microwave-stimulated wet-chemical method. Thermoelectric films of several tens of microns thickness were screen printed onto a flexible polyimide substrate followed by cold compaction and sintering. The n-type films demonstrate a peak ZT of 0.43 along with superior flexibility, which is among the highest reported ZT values in flexible thermoelectric materials. A flexible thermoelectric device fabricated using the printed films produces a high power density of 4.1 mW/cm2 with 60 °C temperature difference between the hot side and cold side. The highly scalable and low cost process to fabricate flexible thermoelectric materials and devices demonstrated here opens up many opportunities to transform thermoelectric energy harvesting and cooling applications.

  19. High-performance and flexible thermoelectric films by screen printing solution-processed nanoplate crystals

    Science.gov (United States)

    Varghese, Tony; Hollar, Courtney; Richardson, Joseph; Kempf, Nicholas; Han, Chao; Gamarachchi, Pasindu; Estrada, David; Mehta, Rutvik J.; Zhang, Yanliang

    2016-01-01

    Screen printing allows for direct conversion of thermoelectric nanocrystals into flexible energy harvesters and coolers. However, obtaining flexible thermoelectric materials with high figure of merit ZT through printing is an exacting challenge due to the difficulties to synthesize high-performance thermoelectric inks and the poor density and electrical conductivity of the printed films. Here, we demonstrate high-performance flexible films and devices by screen printing bismuth telluride based nanocrystal inks synthesized using a microwave-stimulated wet-chemical method. Thermoelectric films of several tens of microns thickness were screen printed onto a flexible polyimide substrate followed by cold compaction and sintering. The n-type films demonstrate a peak ZT of 0.43 along with superior flexibility, which is among the highest reported ZT values in flexible thermoelectric materials. A flexible thermoelectric device fabricated using the printed films produces a high power density of 4.1 mW/cm2 with 60 °C temperature difference between the hot side and cold side. The highly scalable and low cost process to fabricate flexible thermoelectric materials and devices demonstrated here opens up many opportunities to transform thermoelectric energy harvesting and cooling applications. PMID:27615036

  20. High-performance and flexible thermoelectric films by screen printing solution-processed nanoplate crystals.

    Science.gov (United States)

    Varghese, Tony; Hollar, Courtney; Richardson, Joseph; Kempf, Nicholas; Han, Chao; Gamarachchi, Pasindu; Estrada, David; Mehta, Rutvik J; Zhang, Yanliang

    2016-09-12

    Screen printing allows for direct conversion of thermoelectric nanocrystals into flexible energy harvesters and coolers. However, obtaining flexible thermoelectric materials with high figure of merit ZT through printing is an exacting challenge due to the difficulties to synthesize high-performance thermoelectric inks and the poor density and electrical conductivity of the printed films. Here, we demonstrate high-performance flexible films and devices by screen printing bismuth telluride based nanocrystal inks synthesized using a microwave-stimulated wet-chemical method. Thermoelectric films of several tens of microns thickness were screen printed onto a flexible polyimide substrate followed by cold compaction and sintering. The n-type films demonstrate a peak ZT of 0.43 along with superior flexibility, which is among the highest reported ZT values in flexible thermoelectric materials. A flexible thermoelectric device fabricated using the printed films produces a high power density of 4.1 mW/cm(2) with 60 °C temperature difference between the hot side and cold side. The highly scalable and low cost process to fabricate flexible thermoelectric materials and devices demonstrated here opens up many opportunities to transform thermoelectric energy harvesting and cooling applications.

  1. Strategic flexibility

    OpenAIRE

    Kim, KiHyung

    2014-01-01

    A flexible system is defined as one that can change the entity's stance, capability or status reacting to a change of the entity's environment. Flexibility has gathered the attention of academic researchers and industry practitioners as an efficient approach to cope with today's volatile environment. As the environments become more unpredictable and volatile, it is imperative for a flexible system to respond quickly to a change in its circumstance. How much flexibility is embedded into the sy...

  2. Advanced solderless flexible thermal link

    Science.gov (United States)

    Williams, Brian G.; Jensen, Scott M.; Batty, J. Clair

    1996-10-01

    Flexible thermal links play an important role int he thermal management of cryogenically cooled components. The purpose of these links is to provide a means of transferring heat from a cooled component to a cooler reservoir with little increase in temperature. The standard soldered approach although effective proves to be time consuming and contributes to added thermal impedances which degrade the performance of the link. For system with little tolerance for temperature differences between cooled components and a cooling source this is undesirable. The authors of this paper have developed a technique by which thin metal foil or braided wire can be attached to metal end blocks without any solder using the swaging process. Swaging provides a fast, simple method for providing a low thermal impedance between the foils and blocks. This paper describes the characteristics of these thermal links in terms of length, mass, thermal resistance, flexibility, and survivability.

  3. Flexible Ablators

    Science.gov (United States)

    Stackpoole, Margaret M. (Inventor); Ghandehari, Ehson M. (Inventor); Thornton, Jeremy J. (Inventor); Covington, Melmoth Alan (Inventor)

    2017-01-01

    A low-density article comprising a flexible substrate and a pyrolizable material impregnated therein, methods of preparing, and devices using the article are disclosed. The pyrolizable material pyrolizes above 350 C and does not flow at temperatures below the pyrolysis temperature. The low-density article remains flexible after impregnation and continues to remain flexible when the pyrolizable material is fully pyrolized.

  4. Danish Cool

    DEFF Research Database (Denmark)

    Toft, Anne Elisabeth

    2016-01-01

    Danish Cool. Keld Helmer-Petersen, Photography and the Photobook Handout exhibition text in English and Chinese by Anne Elisabeth Toft, Curator The exhibition Danish Cool. Keld Helmer-Petersen, Photography and the Photobook presents the ground-breaking work of late Danish photographer Keld Helmer...

  5. Flexible Software for Flexible Scheduling

    Science.gov (United States)

    Economou, Frossie; Jenness, Tim; Tilanus, Remo P. J.; Hirst, Paul; Adamson, Andy J.; Rippa, Mathew; Delorey, Kynan K.; Isaak, Kate G.

    The JAC Observation Management Project (OMP) provides software for the James Clerk Maxwell (JCMT) and the United Kingdom Infrared (UKIRT) telescopes that manages the life-cycle of flexibly scheduled observations. Its aim is to increase observatory efficiency under flexible (queue) scheduled observing, without depriving the principal investigator (PI) of the flexibility associated with classical scheduling.

  6. Conversational Dominance.

    Science.gov (United States)

    Esau, Helmut; Poth, Annette

    Details of conversational behavior can often not be interpreted until the social interaction, including the rights and obligations of the participants, their intent, the topic, etc., has been defined. This paper presents a model of conversation in which the conversational image a person presents in a given conversational situation is a function of…

  7. Water Cooled Mirror Design

    Energy Technology Data Exchange (ETDEWEB)

    Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Holloway, Michael Andrew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pulliam, Elias Noel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-30

    This design is intended to replace the current mirror setup being used for the NorthStar Moly 99 project in order to monitor the target coupon. The existing setup has limited movement for camera alignment and is difficult to align properly. This proposed conceptual design for a water cooled mirror will allow for greater thermal transfer between the mirror and the water block. It will also improve positioning of the mirror by using flexible vacuum hosing and a ball head joint capable of a wide range of motion. Incorporating this design into the target monitoring system will provide more efficient cooling of the mirror which will improve the amount of diffraction caused by the heating of the mirror. The process of aligning the mirror for accurate position will be greatly improved by increasing the range of motion by offering six degrees of freedom.

  8. Forgiveness Flexibility

    Directory of Open Access Journals (Sweden)

    Tuğba Seda Çolak

    2016-01-01

    Full Text Available Forgiveness flexibility is the skill to minimize the negative effect of an event by using cognitive, affective and behavioral skills while taking a stand at the end of an injurious process. A number of studies were conducted to test the flexibility of the structure of forgiveness. The theoretical structure, structural validity and the confirmatory factor analysis supported the theoretical structure of forgiveness flexibility. The criterion validity evaluated in similar manners was found high. Forgiveness flexibility designed as a three dimensional structure and its sub-dimensions was confirmed theoretically as the recognition of forgivenessand the internalization of forgiveness through insight and its practice.

  9. Radiative cooling for thermophotovoltaic systems

    Science.gov (United States)

    Zhou, Zhiguang; Sun, Xingshu; Bermel, Peter

    2016-09-01

    Radiative cooling has recently garnered a great deal of attention for its potential as an alternative method for photovoltaic thermal management. Here, we will consider the limits of radiative cooling for thermal management of electronics broadly, as well as a specific application to thermal power generation. We show that radiative cooling power can increase rapidly with temperature, and is particularly beneficial in systems lacking standard convective cooling. This finding indicates that systems previously operating at elevated temperatures (e.g., 80°C) can be passively cooled close to ambient under appropriate conditions with a reasonable cooling area. To examine these general principles for a previously unexplored application, we consider the problem of thermophotovoltaic (TPV) conversion of heat to electricity via thermal radiation illuminating a photovoltaic diode. Since TPV systems generally operate in vacuum, convective cooling is sharply limited, but radiative cooling can be implemented with proper choice of materials and structures. In this work, realistic simulations of system performance are performed using the rigorous coupled wave analysis (RCWA) techniques to capture thermal emitter radiation, PV diode absorption, and radiative cooling. We subsequently optimize the structural geometry within realistic design constraints to find the best configurations to minimize operating temperature. It is found that low-iron soda-lime glass can potentially cool the PV diode by a substantial amount, even to below ambient temperatures. The cooling effect can be further improved by adding 2D-periodic photonic crystal structures. We find that the improvement of efficiency can be as much as an 18% relative increase, relative to the non-radiatively cooled baseline, as well as a potentially significant improvement in PV diode lifetime.

  10. Conflicting flexibility

    NARCIS (Netherlands)

    De Jong, P.; Schaap, A.

    2011-01-01

    New buildings are designed for first users. For a sustainable approach there are many advantages in designing in flexibility and adjustability in order to enable and facilitate the other sequential users. For the first investor this flexibility is translated into improved exit values due to

  11. Conversion disorder

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000954.htm Conversion disorder To use the sharing features on this page, please enable JavaScript. Conversion disorder is a mental condition in which a person ...

  12. Ventilative Cooling

    DEFF Research Database (Denmark)

    Heiselberg, Per Kvols; Kolokotroni, Maria

    This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state-of-the-art of ventil......This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state...

  13. Wavelength conversion devices and techniques

    DEFF Research Database (Denmark)

    Stubkjær, Kristian; Jørgensen, Carsten; Danielsen, Søren Lykke;

    1996-01-01

    Wavelength division multiplexed (WDM) networks are currently subject to an immense interest because of the extra capacity and flexibility they provide together with the possibilities for graceful system upgrades. For full network flexibility it is very attractive to be able to translate the chann...... wavelengths in an easy way and preferably without opto-electronic conversion. Here, we will first briefly look at advantages of employing optical wavelength converters in WDM networks and next review the optical wavelength conversion devices with emphasis on recent developments....

  14. Cool snacks

    DEFF Research Database (Denmark)

    Grunert, Klaus G; Brock, Steen; Brunsø, Karen

    2016-01-01

    such a product requires an interdisciplinary effort where researchers with backgrounds in psychology, anthropology, media science, philosophy, sensory science and food science join forces. We present the COOL SNACKS project, where such a blend of competences was used first to obtain thorough insight into young...

  15. Flexible Sigmoidoscopy

    Science.gov (United States)

    ... Task Force (USPSTF). Most doctors recommend colonoscopy to screen for colon cancer because colonoscopy shows the entire colon and can remove colon polyps. However, preparing for and performing a flexible sigmoidoscopy may take less time and you may ...

  16. Flexible HVAC System for Lab or Classroom.

    Science.gov (United States)

    Friedan, Jonathan

    2001-01-01

    Discusses an effort to design a heating, ventilation, and air conditioning system flexible enough to accommodate an easy conversion of classrooms to laboratories and dry labs to wet labs. The design's energy efficiency and operations and maintenance are examined. (GR)

  17. Flexible HVAC System for Lab or Classroom.

    Science.gov (United States)

    Friedan, Jonathan

    2001-01-01

    Discusses an effort to design a heating, ventilation, and air conditioning system flexible enough to accommodate an easy conversion of classrooms to laboratories and dry labs to wet labs. The design's energy efficiency and operations and maintenance are examined. (GR)

  18. Stochastic cooling

    Energy Technology Data Exchange (ETDEWEB)

    Bisognano, J.; Leemann, C.

    1982-03-01

    Stochastic cooling is the damping of betatron oscillations and momentum spread of a particle beam by a feedback system. In its simplest form, a pickup electrode detects the transverse positions or momenta of particles in a storage ring, and the signal produced is amplified and applied downstream to a kicker. The time delay of the cable and electronics is designed to match the transit time of particles along the arc of the storage ring between the pickup and kicker so that an individual particle receives the amplified version of the signal it produced at the pick-up. If there were only a single particle in the ring, it is obvious that betatron oscillations and momentum offset could be damped. However, in addition to its own signal, a particle receives signals from other beam particles. In the limit of an infinite number of particles, no damping could be achieved; we have Liouville's theorem with constant density of the phase space fluid. For a finite, albeit large number of particles, there remains a residue of the single particle damping which is of practical use in accumulating low phase space density beams of particles such as antiprotons. It was the realization of this fact that led to the invention of stochastic cooling by S. van der Meer in 1968. Since its conception, stochastic cooling has been the subject of much theoretical and experimental work. The earliest experiments were performed at the ISR in 1974, with the subsequent ICE studies firmly establishing the stochastic cooling technique. This work directly led to the design and construction of the Antiproton Accumulator at CERN and the beginnings of p anti p colliding beam physics at the SPS. Experiments in stochastic cooling have been performed at Fermilab in collaboration with LBL, and a design is currently under development for a anti p accumulator for the Tevatron.

  19. Comparative analysis of thermal storage cooling and storage battery cooling using photovoltaic generation. Part 2. Research on architectural systematization of energy conversion devices; Taiyoko hatsuden ni yoru chikunetsu reibo to chikuden reibo ni tsuite. 2. Energy henkan no kenchiku system ka ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Ito, N.; Kimura, G.; Fukao, S.; Shimizu, T.; Sunaga, N.; Tsunoda, M.; Muro, K.; Yamanaka, S. [Tokyo Metropolitan University, Tokyo (Japan)

    1996-10-27

    For use in energy self-sufficient buildings, a system was studied capable of retaining for its own use the excess of power produced by a photovoltaic power generation system without releasing it to the commercial system. Summertime cooling was considered. The storage battery cooling system was provided with two solar cell systems and, in the daytime, one was used for cooling and the other for charging batteries for nighttime cooling. In the cold heat storage cooling system, cold heat accumulators (red bricks) were provided in the wall and floor, and under the floor, and the floor was a grating for proper ventilation between the room and underfloor space. With the solar cell-driven air conditioner out of operation, cold heat was fed to the room from the underfloor cold heat accumulators by a fan. In storage battery cooling, solar power covered 60% of what the air conditioner used. In the presence of sufficient power in storage, the air conditioner stayed on at night without buying commercial power, when the room temperature was 25{degree}C. In the cold heat accumulation cooling, 50% of the air conditioner power consumption was covered by solar power. It is recommended to install cold heat accumulators not in the room but in a separate space, such as the underfloor space, where they are exposed to the cooling cold air direct from an air conditioner for future retrieval of cold heat. 2 refs., 9 figs., 3 tabs.

  20. A very cool cooling system

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    The NA62 Gigatracker is a jewel of technology: its sensor, which delivers the time of the crossing particles with a precision of less than 200 picoseconds (better than similar LHC detectors), has a cooling system that might become the precursor to a completely new detector technique.   The 115 metre long vacuum tank of the NA62 experiment. The NA62 Gigatracker (GTK) is composed of a set of three innovative silicon pixel detectors, whose job is to measure the arrival time and the position of the incoming beam particles. Installed in the heart of the NA62 detector, the silicon sensors are cooled down (to about -20 degrees Celsius) by a microfluidic silicon device. “The cooling system is needed to remove the heat produced by the readout chips the silicon sensor is bonded to,” explains Alessandro Mapelli, microsystems engineer working in the Physics department. “For the NA62 Gigatracker we have designed a cooling plate on top of which both the silicon sensor and the...

  1. Cooling technique

    Energy Technology Data Exchange (ETDEWEB)

    Salamon, Todd R; Vyas, Brijesh; Kota, Krishna; Simon, Elina

    2017-01-31

    An apparatus and a method are provided. Use is made of a wick structure configured to receive a liquid and generate vapor in when such wick structure is heated by heat transferred from heat sources to be cooled off. A vapor channel is provided configured to receive the vapor generated and direct said vapor away from the wick structure. In some embodiments, heat conductors are used to transfer the heat from the heat sources to the liquid in the wick structure.

  2. Conversational Narcissism.

    Science.gov (United States)

    Vangelisti, Anita L.; And Others

    1990-01-01

    Examines narcissistic communication and the ways it is exhibited in everyday conversation. Identifies the following behavioral referents: boasting, refocusing the topic of conversation on the self, exaggerating hand and body movements, using a loud tone of voice, and "glazing over" when others speak. Suggests that conversational…

  3. Contentious Conversations

    Science.gov (United States)

    Zuidema, Leah A.

    2011-01-01

    The idea of joining a conversation through reading and writing is not new; in his 1941 book "The Philosophy of Literary Form: Studies in Symbolic Action," Kenneth Burke suggests that the acts of reading and writing are like entering a parlor where others are already conversing. The author explores the place of professional debate within NCTE and…

  4. Piping Flexibility

    Science.gov (United States)

    1978-01-01

    A NASA computer program aids Hudson Engineering Corporation, Houston, Texas, in the design and construction of huge petrochemical processing plants like the one shown, which is located at Ju'aymah, Saudi Arabia. The pipes handling the flow of chemicals are subject to a variety of stresses, such as weight and variations in pressure and temperature. Hudson Engineering uses a COSMIC piping flexibility analysis computer program to analyze stresses and unsure the necessary strength and flexibility of the pipes. This program helps the company realize substantial savings in reduced engineering time.

  5. Flexibility conflict?

    NARCIS (Netherlands)

    Delsen, L.W.M.

    2002-01-01

    The chapter deals with the presupposed conflict of interests between employers and employees resulting from a decoupling of operating hours and working times. It starts from the notion that both long operating hours and flexibility are relative concepts. As there is some discretion, the ultimate

  6. Flexible Consumption

    DEFF Research Database (Denmark)

    Holm Jacobsen, Peter; Pallesen, Trine

    This report presents the first findings from our qualitative study of consumer behaviour vis-à-vis flexible consumption. The main of objective of this report is to present our first round of data from Bornholm, and to assist the design of products/services designed in WP6. In the report, we adopt...

  7. The study on Libr- H2O absorption cascading conversion system driven by waste heat for power, cool and heat%废热溴化锂吸收式动力、冷、热量梯阶转换系统分析

    Institute of Scientific and Technical Information of China (English)

    张秀芳; 金苏敏

    2012-01-01

    A LiBr - H20 absorption cascading conversion system driven by waste heat for power, cool and heat wag presented. The system transformed the high - grade energy into power and the relative low - grade energy into cool and heat so as to realize energy cascading conversion and improve the energy utilization of the available waste energy. Waste heat recovery, energy u-tility and its transformation were analyzed in detail by the self - designed computer program. Effect of the gas inlet or outlet temperature on the energy transformation was gained.%介绍了一种利用溴化锂溶液的热力学特性,合理安排废热回收的废热溴化锂吸收式动力、冷、热量梯阶转换系统.该系统将其中一部分高品位的能量进行动力转换,其余转换成热量和冷量,实现能量梯阶转换,提高废热能源中可用能的合理利用率.利用自编的计算程序对系统的废热回收量以及能量利用与转换做了详细分析,得出烟气进出口温度对系统的能量转换的影响.

  8. The Role of Conversation Policy in Carrying Out Agent Conversations

    Energy Technology Data Exchange (ETDEWEB)

    Link, Hamilton E.; Phillips, Laurence R.

    1999-05-20

    Structured conversation diagrams, or conversation specifications, allow agents to have predictable interactions and achieve predefined information-based goals, but they lack the flexibility needed to function robustly in an unpredictable environment. We propose a mechanism that combines a typical conversation structure with a separately established policy to generate an actual conversation. The word "policy" connotes a high-level direction external to a specific planned interaction with the environment. Policies, which describe acceptable procedures and influence decisions, can be applied to broad sets of activity. Based on their observation of issues related to a policy, agents may dynamically adjust their communication patterns. The policy object describes limitations, constraints, and requirements that may affect the conversation in certain circumstances. Using this new mechanism of interaction simplifies the description of individual conversations and allows domain-specific issues to be brought to bear more easily during agent communication. By following the behavior of the conversation specification when possible and deferring to the policy to derive behavior in exceptional circumstances, an agent is able to function predictably under normal situations and still act rationally in abnormal situations. Different conversation policies applied to a given conversation specification can change the nature of the interaction without changing the specification.

  9. ATLAS - Liquid Cooling Systems

    CERN Multimedia

    Bonneau, P.

    1998-01-01

    Photo 1 - Cooling Unit - Side View Photo 2 - Cooling Unit - Detail Manifolds Photo 3 - Cooling Unit - Rear View Photo 4 - Cooling Unit - Detail Pump, Heater and Exchanger Photo 5 - Cooling Unit - Detail Pump and Fridge Photo 6 - Cooling Unit - Front View

  10. Conversion Disorder

    Science.gov (United States)

    ... Recent significant stress or emotional trauma Being female — women are much more likely to develop conversion disorder Having a mental health condition, such as mood or anxiety disorders, dissociative disorder or certain personality disorders Having ...

  11. Conversation Analysis.

    Science.gov (United States)

    Schiffrin, Deborah

    1990-01-01

    Summarizes the current state of research in conversation analysis, referring primarily to six different perspectives that have developed from the philosophy, sociology, anthropology, and linguistics disciplines. These include pragmatics; speech act theory; interactional sociolinguistics; ethnomethodology; ethnography of communication; and…

  12. Conversation Analysis.

    Science.gov (United States)

    Schiffrin, Deborah

    1990-01-01

    Summarizes the current state of research in conversation analysis, referring primarily to six different perspectives that have developed from the philosophy, sociology, anthropology, and linguistics disciplines. These include pragmatics; speech act theory; interactional sociolinguistics; ethnomethodology; ethnography of communication; and…

  13. Strategic conversation

    Directory of Open Access Journals (Sweden)

    Nicholas Asher

    2013-08-01

    Full Text Available Models of conversation that rely on a strong notion of cooperation don’t apply to strategic conversation — that is, to conversation where the agents’ motives don’t align, such as courtroom cross examination and political debate. We provide a game-theoretic framework that provides an analysis of both cooperative and strategic conversation. Our analysis features a new notion of safety that applies to implicatures: an implicature is safe when it can be reliably treated as a matter of public record. We explore the safety of implicatures within cooperative and non cooperative settings. We then provide a symbolic model enabling us (i to prove a correspondence result between a characterisation of conversation in terms of an alignment of players’ preferences and one where Gricean principles of cooperative conversation like Sincerity hold, and (ii to show when an implicature is safe and when it is not. http://dx.doi.org/10.3765/sp.6.2 BibTeX info

  14. Flexible isotopy classification of flexible links

    OpenAIRE

    Björklund, Johan

    2012-01-01

    In this paper we define and study flexible links and flexible isotopy in projective space. Flexible links are meant to capture the topological properties of real algebraic links. We classify all flexible links up to flexible isotopy using Ekholms interpretation of Viros encomplexed writhe.

  15. Flexible Capitalism

    DEFF Research Database (Denmark)

    Approaching “work” as at heart a practice of exchange, this volume explores sociality in work environments marked by the kind of structural changes that have come to define contemporary “flexible” capitalism. It introduces anthropological exchange theory to a wider readership, and shows how...... the perspective offers new ways to enquire about the flexible capitalism’s social dimensions. The essays contribute to a trans-disciplinary scholarship on contemporary economic practice and change by documenting how, across diverse settings, “gift-like” socialities proliferate, and even sustain the intensified...... flexible commoditization that more commonly is touted as tearing social relations apart. By interrogating a keenly debated contemporary work regime through an approach to sociality rooted in a rich and distinct anthropological legacy, the volume also makes a novel contribution to the anthropological...

  16. Leadership is a conversation.

    Science.gov (United States)

    Groysberg, Boris; Slind, Michael

    2012-06-01

    Globalization and new technologies have sharply reduced the efficacy of command-and-control management and its accompanying forms of corporate communication. In the course of a recent research project, the authors concluded that by talking with employees, rather than simply issuing orders, leaders can promote operational flexibility, employee engagement, and tight strategic alignment. Groysberg and Slind have identified four elements of organizational conversation that reflect the essential attributes of interpersonal conversation: intimacy, interactivity, inclusion, and intentionality. Intimacy shifts the focus from a top-down distribution of information to a bottom-up exchange of ideas. Organizational conversation is less corporate in tone and more casual. And it's less about issuing and taking orders than about asking and answering questions. Interactivity entails shunning the simplicity of monologue and embracing the unpredictable vitality of dialogue. Traditional one-way media-print and broadcast, in particular-give way to social media buttressed by social thinking. Inclusion turns employees into full-fledged conversation partners, entitling them to provide their own ideas, often on company channels. They can create content and act as brand ambassadors, thought leaders, and storytellers. Intentionality enables leaders and employees to derive strategically relevant action from the push and pull of discussion and debate.

  17. Cool visitors

    CERN Multimedia

    2006-01-01

    Pictured, from left to right: Tim Izo (saxophone, flute, guitar), Bobby Grant (tour manager), George Pajon (guitar). What do the LHC and a world-famous hip-hop group have in common? They are cool! On Saturday, 1st July, before their appearance at the Montreux Jazz Festival, three members of the 'Black Eyed Peas' came on a surprise visit to CERN, inspired by Dan Brown's Angels and Demons. At short notice, Connie Potter (Head of the ATLAS secretariat) organized a guided tour of ATLAS and the AD 'antimatter factory'. Still curious, lead vocalist Will.I.Am met CERN physicist Rolf Landua after the concert to ask many more questions on particles, CERN, and the origin of the Universe.

  18. Direct Conversion of Energy

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, William R

    1964-01-01

    Topics include: direct versus dynamic energy conversion; laws governing energy conversion; thermoelectricity; thermionic conversion; magnetohydrodynamic conversion; chemical batteries; the fuel cell; solar cells; nuclear batteries; and advanced concepts including ferroelectric conversion and thermomagnetic conversion.

  19. A study on cooling efficiency using 1-d analysis code suitable for cooling system of thermoforming

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhen Zhe; Heo, Kwang Su; Xuan, Dong Ji; Seol, Seoung Yun [Chonnam National University, Gwangju (Korea, Republic of)

    2009-03-15

    Thermoforming is one of the most versatile and economical processes available for polymer products, but cycle time and production cost must be continuously reduced in order to improve the competitive power of products. In this study, water spray cooling was simulated to apply to a cooling system instead of compressed air cooling in order to shorten the cycle time and reduce the cost of compressed air used in the cooling process. At first, cooling time using compressed air was predicted in order to check the state of mass production. In the following step, the ratio of removed energy by air cooling or water spray cooling among the total removed energy was found by using 1-D analysis code of the cooling system under the condition of checking the possibility of conversion from 2-D to 1-D problem. The analysis results using water spray cooling show that cycle time can be reduced because of high cooling efficiency of water spray, and cost of production caused by using compressed air can be reduced by decreasing the amount of the used compressed air. The 1-D analysis code can be widely used in the design of a thermoforming cooling system, and parameters of the thermoforming process can be modified based on the recommended data suitable for a cooling system of thermoforming

  20. Flexible Capitalism

    DEFF Research Database (Denmark)

    Approaching “work” as at heart a practice of exchange, this volume explores sociality in work environments marked by the kind of structural changes that have come to define contemporary “flexible” capitalism. It introduces anthropological exchange theory to a wider readership, and shows how...... the perspective offers new ways to enquire about the flexible capitalism’s social dimensions. The essays contribute to a trans-disciplinary scholarship on contemporary economic practice and change by documenting how, across diverse settings, “gift-like” socialities proliferate, and even sustain the intensified...

  1. Convective cooling of photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, E.; Gibbons, C. [Energy Engineering Group, Mechanical Engineering Department, Cork Institute of Technology, Bishopstown, Cork (Ireland)

    2004-07-01

    Most solar cells presently on the market are based on silicon wafers, the so-called first generation technology. As this technology has matured costs have become increasingly dominated by material costs. In the last ten years, continuous work has brought the efficiency of standard cells to the 25% region. A switch to second generation or thin film technology cells now seems imminent. Thin film technology eliminates the silicon wafer and offer the prospect of reducing material and manufacturing costs, but they exhibit lower efficiencies of around 10% for a commercial device. Third generation or tandem cells are currently at a 'proof of concept' research level, with a theoretical conversion rate of 86.8% being asserted Whatever the material construction and manufacturing method of cells, the thermal effect of overheating will prevail in the semiconductor and it is accepted that a lowered temperature will bring about an increase in conversion efficiency. The aim of this project is to improve the efficiency of PV electrical output, by convectively cooling the cells through perforations in them. As the cells heat up they lose efficiency. As the panel heats up a loss in efficiency of 0.5% per C increase in temperature has been recorded. (orig.)

  2. Continuous compliance compensation of position-dependent flexible structures

    NARCIS (Netherlands)

    Kontaras, Nikolaos; Heertjes, Marcel; Zwart, Hans

    2016-01-01

    The implementation of lightweight high-performance motion systems in lithography and other applications imposes lower requirements on actuators, amplifiers, and cooling. However, the decreased stiffness of lightweight designs increases the effect of structural flexibilities especially when the point

  3. Conversational Telugu.

    Science.gov (United States)

    Beinstein, Judith; And Others

    The purpose of this text is to develop elementary conversational skills in Telugu. The language materials consist of four types of language learning activities. The first, and most predominant, is the unit microwave cycle. These cycles divide the learning process into two basic phases, the first of which involves mimicry, memorization, and…

  4. Conversion Disorder

    National Research Council Canada - National Science Library

    Fisher, Robert S; Stonnington, Cynthia M; Barry, John J

    2006-01-01

    ... to proceed after establishing a diagnosis of conversion disorder. Case Presentation "Ms. A," a 53-year-old left-handed woman, was admitted to our epilepsy monitoring unit for evaluation of a 4-month history of tremors, head bobbing, and episodic loss of awareness. The onset of these symptoms was 1 week after she had visited an emergency department...

  5. Conversion Disorder

    Directory of Open Access Journals (Sweden)

    Yacov Rofé

    2013-11-01

    Full Text Available Conversion disorder remains a mystery that has only become more complicated with the decline of the scientific status of psychoanalysis (e.g., Piper, Lillevik, & Kritzer, 2008; Rofé, 2008 and recent neurological findings suggest that this behavior is controlled by biological mechanisms (van Beilen, Vogt, & Leenders, 2010. Moreover, existing theories have difficulty explaining the efficacy of various interventions, such as psychoanalysis, behavior therapy, drug therapy and religious therapy. This article reviews research and clinical evidence pertaining to both the development and treatment of conversion disorder and shows that this seemingly incompatible evidence can be integrated within a new theory, the Rational-Choice Theory of Neurosis (RCTN; Rofé, 2010. Despite the striking differences, RCTN continues Freud's framework of thinking as it employs a new concept of repression and replaces the unconscious with self-deception. Moreover, it incorporates Freud's idea, implicitly expressed in his theory, that neurotic disorders are, in fact, rational behaviors.

  6. Conversational sensing

    Science.gov (United States)

    Preece, Alun; Gwilliams, Chris; Parizas, Christos; Pizzocaro, Diego; Bakdash, Jonathan Z.; Braines, Dave

    2014-05-01

    Recent developments in sensing technologies, mobile devices and context-aware user interfaces have made it pos- sible to represent information fusion and situational awareness for Intelligence, Surveillance and Reconnaissance (ISR) activities as a conversational process among actors at or near the tactical edges of a network. Motivated by use cases in the domain of Company Intelligence Support Team (CoIST) tasks, this paper presents an approach to information collection, fusion and sense-making based on the use of natural language (NL) and controlled nat- ural language (CNL) to support richer forms of human-machine interaction. The approach uses a conversational protocol to facilitate a ow of collaborative messages from NL to CNL and back again in support of interactions such as: turning eyewitness reports from human observers into actionable information (from both soldier and civilian sources); fusing information from humans and physical sensors (with associated quality metadata); and assisting human analysts to make the best use of available sensing assets in an area of interest (governed by man- agement and security policies). CNL is used as a common formal knowledge representation for both machine and human agents to support reasoning, semantic information fusion and generation of rationale for inferences, in ways that remain transparent to human users. Examples are provided of various alternative styles for user feedback, including NL, CNL and graphical feedback. A pilot experiment with human subjects shows that a prototype conversational agent is able to gather usable CNL information from untrained human subjects.

  7. Operability and flexibility of a milk production line

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    2007-01-01

    parameters. The operability and flexibility of the nominal operating points were evaluated with a minimization of the process pasteurization and cooling temp. through vertex enumeration. The simulation procedure provides a quantitative method for developing a flexible process in dairy industry applications...

  8. Roadmap on optical energy conversion

    Science.gov (United States)

    Boriskina, Svetlana V.; Green, Martin A.; Catchpole, Kylie; Yablonovitch, Eli; Beard, Matthew C.; Okada, Yoshitaka; Lany, Stephan; Gershon, Talia; Zakutayev, Andriy; Tahersima, Mohammad H.; Sorger, Volker J.; Naughton, Michael J.; Kempa, Krzysztof; Dagenais, Mario; Yao, Yuan; Xu, Lu; Sheng, Xing; Bronstein, Noah D.; Rogers, John A.; Alivisatos, A. Paul; Nuzzo, Ralph G.; Gordon, Jeffrey M.; Wu, Di M.; Wisser, Michael D.; Salleo, Alberto; Dionne, Jennifer; Bermel, Peter; Greffet, Jean-Jacques; Celanovic, Ivan; Soljacic, Marin; Manor, Assaf; Rotschild, Carmel; Raman, Aaswath; Zhu, Linxiao; Fan, Shanhui; Chen, Gang

    2016-07-01

    For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in the optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light-matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. It is our hope that the roadmap

  9. Roadmap on optical energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Boriskina, Svetlana V.; Green, Martin A.; Catchpole, Kylie; Yablonovitch, Eli; Beard, Matthew C.; Okada, Yoshitaka; Lany, Stephan; Gershon, Talia; Zakutayev, Andriy; Tahersima, Mohammad H.; Sorger, Volker J.; Naughton, Michael J.; Kempa, Krzysztof; Dagenais, Mario; Yao, Yuan; Xu, Lu; Sheng, Xing; Bronstein, Noah D.; Rogers, John A.; Alivisatos, A. Paul; Nuzzo, Ralph G.; Gordon, Jeffrey M.; Wu, Di M.; Wisser, Michael D.; Salleo, Alberto; Dionne, Jennifer; Bermel, Peter; Greffet, Jean-Jacques; Celanovic, Ivan; Soljacic, Marin; Manor, Assaf; Rotschild, Carmel; Raman, Aaswath; Zhu, Linxiao; Fan, Shanhui; Chen, Gang

    2016-06-24

    For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in the optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light-matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. It is our hope that the roadmap

  10. Geothermal energy conversion facility

    Energy Technology Data Exchange (ETDEWEB)

    Kutscher, C.F.

    1997-12-31

    With the termination of favorable electricity generation pricing policies, the geothermal industry is exploring ways to improve the efficiency of existing plants and make them more cost-competitive with natural gas. The Geothermal Energy Conversion Facility (GECF) at NREL will allow researchers to study various means for increasing the thermodynamic efficiency of binary cycle geothermal plants. This work has received considerable support from the US geothermal industry and will be done in collaboration with industry members and utilities. The GECF is being constructed on NREL property at the top of South Table Mountain in Golden, Colorado. As shown in Figure 1, it consists of an electrically heated hot water loop that provides heating to a heater/vaporizer in which the working fluid vaporizes at supercritical or subcritical pressures as high as 700 psia. Both an air-cooled and water-cooled condenser will be available for condensing the working fluid. In order to minimize construction costs, available equipment from the similar INEL Heat Cycle Research Facility is being utilized.

  11. Quantum optical waveform conversion

    CERN Document Server

    Kielpinski, D; Wiseman, HM

    2010-01-01

    Currently proposed architectures for long-distance quantum communication rely on networks of quantum processors connected by optical communications channels [1,2]. The key resource for such networks is the entanglement of matter-based quantum systems with quantum optical fields for information transmission. The optical interaction bandwidth of these material systems is a tiny fraction of that available for optical communication, and the temporal shape of the quantum optical output pulse is often poorly suited for long-distance transmission. Here we demonstrate that nonlinear mixing of a quantum light pulse with a spectrally tailored classical field can compress the quantum pulse by more than a factor of 100 and flexibly reshape its temporal waveform, while preserving all quantum properties, including entanglement. Waveform conversion can be used with heralded arrays of quantum light emitters to enable quantum communication at the full data rate of optical telecommunications.

  12. Hybrid radiator cooling system

    Science.gov (United States)

    France, David M.; Smith, David S.; Yu, Wenhua; Routbort, Jules L.

    2016-03-15

    A method and hybrid radiator-cooling apparatus for implementing enhanced radiator-cooling are provided. The hybrid radiator-cooling apparatus includes an air-side finned surface for air cooling; an elongated vertically extending surface extending outwardly from the air-side finned surface on a downstream air-side of the hybrid radiator; and a water supply for selectively providing evaporative cooling with water flow by gravity on the elongated vertically extending surface.

  13. Flexible Electronics Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Flexible Electronics Research Facility designs, synthesizes, tests, and fabricates materials and devices compatible with flexible substrates for Army information...

  14. Liquid-Cooled Garment

    Science.gov (United States)

    1977-01-01

    A liquid-cooled bra, offshoot of Apollo moon suit technology, aids the cancer-detection technique known as infrared thermography. Water flowing through tubes in the bra cools the skin surface to improve resolution of thermograph image.

  15. Data center cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Chainer, Timothy J; Dang, Hien P; Parida, Pritish R; Schultz, Mark D; Sharma, Arun

    2015-03-17

    A data center cooling system may include heat transfer equipment to cool a liquid coolant without vapor compression refrigeration, and the liquid coolant is used on a liquid cooled information technology equipment rack housed in the data center. The system may also include a controller-apparatus to regulate the liquid coolant flow to the liquid cooled information technology equipment rack through a range of liquid coolant flow values based upon information technology equipment temperature thresholds.

  16. Stochastic cooling in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Brennan,J.M.; Blaskiewicz, M. M.; Severino, F.

    2009-05-04

    After the success of longitudinal stochastic cooling of bunched heavy ion beam in RHIC, transverse stochastic cooling in the vertical plane of Yellow ring was installed and is being commissioned with proton beam. This report presents the status of the effort and gives an estimate, based on simulation, of the RHIC luminosity with stochastic cooling in all planes.

  17. Balance and flexibility.

    Science.gov (United States)

    2003-12-01

    The 'work-life balance' and flexible working are currently key buzz terms in the NHS. Those looking for more information on these topics should visit Flexibility at www.flexibility.co.uk for a host of resources designed to support new ways of working, including information on flexible workers and flexible rostering, the legal balancing act for work-life balance and home working.

  18. Remodeling, Renovation, & Conversion of Educational Facilities.

    Science.gov (United States)

    Association of Physical Plant Administrators of Universities and Colleges, Washington, DC.

    Based on a series of workshops, this collection of papers provides a framework for thought--emphasizing planning within time, flexibility, and maintenance constraints--as well as a practical guide for actual engineering of remodeling/renovation/conversion projects. Is remodeling always less expensive than new construction? Should high initial…

  19. Laser cooling of solids

    OpenAIRE

    Nemova, Galina

    2009-01-01

    Parallel to advances in laser cooling of atoms and ions in dilute gas phase, which has progressed immensely, resulting in physics Nobel prizes in 1997 and 2001, major progress has recently been made in laser cooling of solids. I compare the physical nature of the laser cooling of atoms and ions with that of the laser cooling of solids. I point out all advantages of this new and very promising area of laser physics. Laser cooling of solids (optical refrigeration) at the present time can be lar...

  20. Optomechanical Light-Matter Interface with Optical Wavelength Conversion

    Science.gov (United States)

    2015-07-21

    Conversion Hailin Wang Department of Physics , University of Oregon, Eugene, OR 97403 Lin Tian School of Natural Science, University of California...the physical process can be exactly mapped to a cooling equation where the mechanical noise is extracted away from the system. In the physical ... electromechanical systems. Mechanically-mediated 14 DISTRIBUTION A: Distribution approved for public release. optical wavelength conversion, including

  1. High-Performance Flexible Waveguiding Photovoltaics

    Science.gov (United States)

    Chou, Chun-Hsien; Chuang, Jui-Kang; Chen, Fang-Chung

    2013-07-01

    The use of flat-plane solar concentrators is an effective approach toward collecting sunlight economically and without sun trackers. The optical concentrators are, however, usually made of rigid glass or plastics having limited flexibility, potentially restricting their applicability. In this communication, we describe flexible waveguiding photovoltaics (FWPVs) that exhibit high optical efficiencies and great mechanical flexibility. We constructed these FWPVs by integrating poly-Si solar cells, a soft polydimethylsiloxane (PDMS) waveguide, and a TiO2-doped backside reflector. Optical microstructures that increase the light harvesting ability of the FWPVs can be fabricated readily, through soft lithography, on the top surface of the PDMS waveguide. Our optimized structure displayed an optical efficiency of greater than 42% and a certified power conversion efficiency (PCE) of 5.57%, with a projected PCE as high as approximately 18%. This approach might open new avenues for the harvesting of solar energy at low cost with efficient, mechanically flexible photovoltaics.

  2. Stochastic cooling in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Brennan J. M.; Blaskiewicz, M.; Mernick, K.

    2012-05-20

    The full 6-dimensional [x,x'; y,y'; z,z'] stochastic cooling system for RHIC was completed and operational for the FY12 Uranium-Uranium collider run. Cooling enhances the integrated luminosity of the Uranium collisions by a factor of 5, primarily by reducing the transverse emittances but also by cooling in the longitudinal plane to preserve the bunch length. The components have been deployed incrementally over the past several runs, beginning with longitudinal cooling, then cooling in the vertical planes but multiplexed between the Yellow and Blue rings, next cooling both rings simultaneously in vertical (the horizontal plane was cooled by betatron coupling), and now simultaneous horizontal cooling has been commissioned. The system operated between 5 and 9 GHz and with 3 x 10{sup 8} Uranium ions per bunch and produces a cooling half-time of approximately 20 minutes. The ultimate emittance is determined by the balance between cooling and emittance growth from Intra-Beam Scattering. Specific details of the apparatus and mathematical techniques for calculating its performance have been published elsewhere. Here we report on: the method of operation, results with beam, and comparison of results to simulations.

  3. Direct jet impingement cooling of power electronics

    OpenAIRE

    Skuriat, Robert

    2012-01-01

    The aim of the work presented in this thesis is to improve the operational reliability of a power module and increase the efficiency of its associated cooling system by integrating the design of the cooler as part of the module. Power modules are increasingly used in a variety of applications ranging from aircraft and mass transport systems, to motor control and power conversion in the home. Reliability of the power module is very important in aerospace applications where the highest levels o...

  4. Cooling by Thermodynamic Induction

    Science.gov (United States)

    Patitsas, S. N.

    2017-03-01

    A method is described for cooling conductive channels to below ambient temperature. The thermodynamic induction principle dictates that the electrically biased channel will cool if the electrical conductance decreases with temperature. The extent of this cooling is calculated in detail for both cases of ballistic and conventional transport with specific calculations for carbon nanotubes and conventional metals, followed by discussions for semiconductors, graphene, and metal-insulator transition systems. A theorem is established for ballistic transport stating that net cooling is not possible. For conventional transport, net cooling is possible over a broad temperature range, with the range being size-dependent. A temperature clamping scheme for establishing a metastable nonequilibrium stationary state is detailed and followed with discussion of possible applications to on-chip thermoelectric cooling in integrated circuitry and quantum computer systems.

  5. Cooling by Thermodynamic Induction

    Science.gov (United States)

    Patitsas, S. N.

    2016-11-01

    A method is described for cooling conductive channels to below ambient temperature. The thermodynamic induction principle dictates that the electrically biased channel will cool if the electrical conductance decreases with temperature. The extent of this cooling is calculated in detail for both cases of ballistic and conventional transport with specific calculations for carbon nanotubes and conventional metals, followed by discussions for semiconductors, graphene, and metal-insulator transition systems. A theorem is established for ballistic transport stating that net cooling is not possible. For conventional transport, net cooling is possible over a broad temperature range, with the range being size-dependent. A temperature clamping scheme for establishing a metastable nonequilibrium stationary state is detailed and followed with discussion of possible applications to on-chip thermoelectric cooling in integrated circuitry and quantum computer systems.

  6. Radiant Floor Cooling Systems

    DEFF Research Database (Denmark)

    Olesen, Bjarne W.

    2008-01-01

    In many countries, hydronic radiant floor systems are widely used for heating all types of buildings such as residential, churches, gymnasiums, hospitals, hangars, storage buildings, industrial buildings, and smaller offices. However, few systems are used for cooling.This article describes a floor...... cooling system that includes such considerations as thermal comfort of the occupants, which design parameters will influence the cooling capacity and how the system should be controlled. Examples of applications are presented....

  7. Laser cooling in semiconductors (Conference Presentation)

    Science.gov (United States)

    Zhang, Jun

    2017-06-01

    Laser cooling of semiconductor is very important topic in science researches and technological applications. Here we will report our progresses on laser cooling in semiconductors. By using of strong coupling between excitons and longitudinal optical phonons (LOPs), which allows the resonant annihilation of multiple LOPs in luminescence up-conversion processes, we observe a net cooling by about 40 K starting from 290 kelvin with 514-nm pumping and about 15 K starting from100 K with 532-nm pumping in a semiconductor using group-II-VI cadmium sulphide nanobelts. We also discuss the thickness dependence of laser cooing in CdS nanobelts, a concept porotype of semiconductor cryocooler and possibility of laser cooling in II-VI semiconductor family including CdSSe、CdSe, CdSe/ZnTe QDs and bulk CdS et al., Beyond II-VI semiconductor, we will present our recent progress in laser cooling of organic-inorganic perovskite materials, which show a very big cooling power and external quantum efficiency in 3D and 2D case. Further more, we demonstrate a resolved sideband Raman cooling of a specific LO phonon in ZnTe, in which only one specific phonon resonant with exciton can be cooled or heated. In the end, we will discuss the nonlinear anti-Stokes Raman and anti-Stokes photoluminescence upcoversion in very low temperature as low as down to liquid 4.2 K. In this case, the anti-Stokes resonance induces a quadratic power denpendece of anti-Stokes Raman and anti-Stokes PL. We proposed a CARS-like process to explain it. This nonlinear process also provides a possible physics picture of ultra-low temperatures phonon assisted photoluminescence and anti-Stokes Raman process.

  8. maximizing patient care revenue throughout a major HIS conversion.

    Science.gov (United States)

    Blair, Kelley; Dunn, Elaine

    2015-02-01

    Appointing a revenue point person during a health information system (HIS) conversion ensures revenue remains a priority. Part of the preparation for an HIS conversion should be to clean up the accounts receivable backlog, which provides a revenue boost. Flexible staffing approaches to augment staff, as necessary, should be adopted to address areas that will require heightened attention during the conversion. The postconversion strategy, including audits and staff education, should aim to derive maximum value from the new system.

  9. Initial Cooling Experiment (ICE)

    CERN Multimedia

    Photographic Service

    1978-01-01

    In 1977, in a record-time of 9 months, the magnets of the g-2 experiment were modified and used to build a proton/antiproton storage ring: the "Initial Cooling Experiment" (ICE). It served for the verification of the cooling methods to be used for the "Antiproton Project". Stochastic cooling was proven the same year, electron cooling followed later. Also, with ICE the experimental lower limit for the antiproton lifetime was raised by 9 orders of magnitude: from 2 microseconds to 32 hours. For its previous life as g-2 storage ring, see 7405430. More on ICE: 7711282, 7809081, 7908242.

  10. High energy electron cooling

    Energy Technology Data Exchange (ETDEWEB)

    Parkhomchuk, V. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation)

    1997-09-01

    High energy electron cooling requires a very cold electron beam. The questions of using electron cooling with and without a magnetic field are presented for discussion at this workshop. The electron cooling method was suggested by G. Budker in the middle sixties. The original idea of the electron cooling was published in 1966. The design activities for the NAP-M project was started in November 1971 and the first run using a proton beam occurred in September 1973. The first experiment with both electron and proton beams was started in May 1974. In this experiment good result was achieved very close to theoretical prediction for a usual two component plasma heat exchange.

  11. Power electronics cooling apparatus

    Science.gov (United States)

    Sanger, Philip Albert; Lindberg, Frank A.; Garcen, Walter

    2000-01-01

    A semiconductor cooling arrangement wherein a semiconductor is affixed to a thermally and electrically conducting carrier such as by brazing. The coefficient of thermal expansion of the semiconductor and carrier are closely matched to one another so that during operation they will not be overstressed mechanically due to thermal cycling. Electrical connection is made to the semiconductor and carrier, and a porous metal heat exchanger is thermally connected to the carrier. The heat exchanger is positioned within an electrically insulating cooling assembly having cooling oil flowing therethrough. The arrangement is particularly well adapted for the cooling of high power switching elements in a power bridge.

  12. Flexible alternatives to constant frequency systems

    Science.gov (United States)

    Stewart-Wilson, John

    The use of hybrid systems in which variable frequency is used as generated, with a proportion being converted to constant frequency by electronic conversion, is examined as a flexible alternative to constant frequency systems. Here, some practical solutions to the technical issues raised by adopting the more flexible approach to electrical system generation are presented. In particular, attention is given to the frequency ranges used, impact on aircraft equipment, motor-driven equipment, transformer rectifier units, lighting, and avionics. The discussion also covers fan-assisted galley ovens, system architecture, special airworthiness requirements, and power quality.

  13. Liquid metal cooled reactors for space power applications

    Science.gov (United States)

    Bailey, S.; Vaidyanathan, S.; Van Hoomissen, J.

    1985-01-01

    The technology basis for evaluation of liquid metal cooled space reactors is summarized. Requirements for space nuclear power which are relevant to selection of the reactor subsystem are then reviewed. The attributes of liquid metal cooled reactors are considered in relation to these requirements in the areas of liquid metal properties, neutron spectrum characteristics, and fuel form. Key features of typical reactor designs are illustrated. It is concluded that liquid metal cooled fast spectrum reactors provide a high confidence, flexible option for meeting requirements for SP-100 and beyond.

  14. Preliminary Report: Controller Prototyping and Validation for Photo-Voltaic Comfort Cooling

    DEFF Research Database (Denmark)

    Agesen, Mads Kronborg; Skou, Arne Joachim; Pedersen, Keld Lotzfeldt

    2016-01-01

    cells, and this paper investigates, demonstrates and validates the feasibility of providing energy efficient comfort cooling with a low environmental impact, while offering flexibility to the electrical grid. Also, the possibility of reusing unmodified existing CTS systems is investigated. Finally...

  15. Elastocaloric cooling: Stretch to actively cool

    Science.gov (United States)

    Ossmer, Hinnerk; Kohl, Manfred

    2016-10-01

    The elastocaloric effect can be exploited in solid-state cooling technologies as an alternative to conventional vapour compression. Now, an elastocaloric device based on the concept of active regeneration achieves a temperature lift of 15.3 K and efficiencies competitive with other caloric-based approaches.

  16. Measure Guideline: Ventilation Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Springer, D.; Dakin, B.; German, A.

    2012-04-01

    The purpose of this measure guideline on ventilation cooling is to provide information on a cost-effective solution for reducing cooling system energy and demand in homes located in hot-dry and cold-dry climates. This guideline provides a prescriptive approach that outlines qualification criteria, selection considerations, and design and installation procedures.

  17. The final cool down

    CERN Multimedia

    Thursday 29th May, the cool-down of the final sector (sector 4-5) of LHC has begun, one week after the start of the cool-down of sector 1-2. It will take five weeks for the sectors to be cooled from room temperature to 5 K and a further two weeks to complete the cool down to 1.9 K and the commissioning of cryogenic instrumentation, as well as to fine tune the cryogenic plants and the cooling loops of cryostats.Nearly a year and half has passed since sector 7-8 was cooled for the first time in January 2007. For Laurent Tavian, AT/CRG Group Leader, reaching the final phase of the cool down is an important milestone, confirming the basic design of the cryogenic system and the ability to operate complete sectors. “All the sectors have to operate at the same time otherwise we cannot inject the beam into the machine. The stability and reliability of the cryogenic system and its utilities are now very important. That will be the new challenge for the coming months,” he explains. The status of the cool down of ...

  18. Solar absorption cooling

    NARCIS (Netherlands)

    Kim, D.-S.

    2007-01-01

    As the world concerns more and more on global climate changes and depleting energy resources, solar cooling technology receives increasing interests from the public as an environment-friendly and sustainable alternative. However, making a competitive solar cooling machine for the market still

  19. Passive evaporative cooling

    NARCIS (Netherlands)

    Tzoulis, A.

    2011-01-01

    This "designers' manual" is made during the TIDO-course AR0531 Smart & Bioclimatic Design. Passive techniques for cooling are a great way to cope with the energy problem of the present day. This manual introduces passive cooling by evaporation. These methods have been used for many years in traditi

  20. Data center cooling method

    Energy Technology Data Exchange (ETDEWEB)

    Chainer, Timothy J.; Dang, Hien P.; Parida, Pritish R.; Schultz, Mark D.; Sharma, Arun

    2015-08-11

    A method aspect for removing heat from a data center may use liquid coolant cooled without vapor compression refrigeration on a liquid cooled information technology equipment rack. The method may also include regulating liquid coolant flow to the data center through a range of liquid coolant flow values with a controller-apparatus based upon information technology equipment temperature threshold of the data center.

  1. Liquid Cooled Garments

    Science.gov (United States)

    1979-01-01

    Astronauts working on the surface of the moon had to wear liquid-cooled garments under their space suits as protection from lunar temperatures which sometimes reach 250 degrees Fahrenheit. In community service projects conducted by NASA's Ames Research Center, the technology developed for astronaut needs has been adapted to portable cooling systems which will permit two youngsters to lead more normal lives.

  2. Solar absorption cooling

    NARCIS (Netherlands)

    Kim, D.-S.

    2007-01-01

    As the world concerns more and more on global climate changes and depleting energy resources, solar cooling technology receives increasing interests from the public as an environment-friendly and sustainable alternative. However, making a competitive solar cooling machine for the market still remain

  3. Coherent electron cooling

    Energy Technology Data Exchange (ETDEWEB)

    Litvinenko,V.

    2009-05-04

    Cooling intense high-energy hadron beams remains a major challenge in modern accelerator physics. Synchrotron radiation is still too feeble, while the efficiency of two other cooling methods, stochastic and electron, falls rapidly either at high bunch intensities (i.e. stochastic of protons) or at high energies (e-cooling). In this talk a specific scheme of a unique cooling technique, Coherent Electron Cooling, will be discussed. The idea of coherent electron cooling using electron beam instabilities was suggested by Derbenev in the early 1980s, but the scheme presented in this talk, with cooling times under an hour for 7 TeV protons in the LHC, would be possible only with present-day accelerator technology. This talk will discuss the principles and the main limitations of the Coherent Electron Cooling process. The talk will describe the main system components, based on a high-gain free electron laser driven by an energy recovery linac, and will present some numerical examples for ions and protons in RHIC and the LHC and for electron-hadron options for these colliders. BNL plans a demonstration of the idea in the near future.

  4. Modeling gasodynamic vortex cooling

    Science.gov (United States)

    Allahverdyan, A. E.; Fauve, S.

    2017-08-01

    We aim at studying gasodynamic vortex cooling in an analytically solvable, thermodynamically consistent model that can explain limitations on the cooling efficiency. To this end, we study an angular plus radial flow between two (coaxial) rotating permeable cylinders. Full account is taken of compressibility, viscosity, and heat conductivity. For a weak inward radial flow the model qualitatively describes the vortex cooling effect, in terms of both temperature and the decrease of the stagnation enthalpy, seen in short uniflow vortex (Ranque) tubes. The cooling does not result from external work and its efficiency is defined as the ratio of the lowest temperature reached adiabatically (for the given pressure gradient) to the lowest temperature actually reached. We show that for the vortex cooling the efficiency is strictly smaller than 1, but in another configuration with an outward radial flow, we find that the efficiency can be larger than 1. This is related to both the geometry and the finite heat conductivity.

  5. Hydronic rooftop cooling systems

    Science.gov (United States)

    Bourne, Richard C.; Lee, Brian Eric; Berman, Mark J.

    2008-01-29

    A roof top cooling unit has an evaporative cooling section that includes at least one evaporative module that pre-cools ventilation air and water; a condenser; a water reservoir and pump that captures and re-circulates water within the evaporative modules; a fan that exhausts air from the building and the evaporative modules and systems that refill and drain the water reservoir. The cooling unit also has a refrigerant section that includes a compressor, an expansion device, evaporator and condenser heat exchangers, and connecting refrigerant piping. Supply air components include a blower, an air filter, a cooling and/or heating coil to condition air for supply to the building, and optional dampers that, in designs that supply less than 100% outdoor air to the building, control the mixture of return and ventilation air.

  6. INITIAL COOLING EXPERIMENT (ICE)

    CERN Multimedia

    1979-01-01

    ICE was built in 1977, using the modified bending magnets of the g-2 muon storage ring (see 7405430). Its purpose was to verify the validity of stochastic and electron cooling for the antiproton project. Stochastic cooling proved a resounding success early in 1978 and the antiproton project could go ahead, now entirely based on stochastic cooling. Electron cooling was experimented with in 1979. The 26 kV equipment is housed in the cage to the left of the picture, adjacent to the "e-cooler" located in a straight section of the ring. With some modifications, the cooler was later transplanted into LEAR (Low Energy Antiproton Ring) and then, with further modifications, into the AD (Antiproton Decelerator), where it cools antiprotons to this day (2006). See also: 7711282, 7802099, 7809081.

  7. INITIAL COOLING EXPERIMENT (ICE)

    CERN Multimedia

    1978-01-01

    ICE was built in 1977, in a record time of 9 months, using the modified bending magnets of the g-2 muon storage ring. Its purpose was to verify the validity of stochastic and electron cooling for the antiproton project, to be launched in 1978. Already early in 1978, stochastic cooling proved a resounding success, such that the antiproton (p-pbar)project was entirely based on it. Tests of electron cooling followed later: protons of 46 MeV kinetic energy were cooled with an electron beam of 26 kV and 1.3 A. The cage seen prominently in the foreground houses the HV equipment, adjacent to the "cooler" installed in a straight section of the ring. With some modifications, the cooler was later transplanted into LEAR (Low Energy Antiproton Ring) and then, with further modifications, into the AD (Antiproton Decelerator), where it cools antiprotons to this day (2006). See also: 7711282, 7802099, 7908242.

  8. Flexible network wireless transceiver and flexible network telemetry transceiver

    Science.gov (United States)

    Brown, Kenneth D.

    2008-08-05

    A transceiver for facilitating two-way wireless communication between a baseband application and other nodes in a wireless network, wherein the transceiver provides baseband communication networking and necessary configuration and control functions along with transmitter, receiver, and antenna functions to enable the wireless communication. More specifically, the transceiver provides a long-range wireless duplex communication node or channel between the baseband application, which is associated with a mobile or fixed space, air, water, or ground vehicle or other platform, and other nodes in the wireless network or grid. The transceiver broadly comprises a communication processor; a flexible telemetry transceiver including a receiver and a transmitter; a power conversion and regulation mechanism; a diplexer; and a phased array antenna system, wherein these various components and certain subcomponents thereof may be separately enclosed and distributable relative to the other components and subcomponents.

  9. Second sector cool down

    CERN Multimedia

    2007-01-01

    At the beginning of July, cool-down is starting in the second LHC sector, sector 4-5. The cool down of sector 4-5 may occasionally generate mist at Point 4, like that produced last January (photo) during the cool-down of sector 7-8.Things are getting colder in the LHC. Sector 7-8 has been kept at 1.9 K for three weeks with excellent stability (see Bulletin No. 16-17 of 16 April 2007). The electrical tests in this sector have got opt to a successful start. At the beginning of July the cryogenic teams started to cool a second sector, sector 4-5. At Point 4 in Echenevex, where one of the LHC’s cryogenic plants is located, preparations for the first phase of the cool-down are underway. During this phase, the sector will first be cooled to 80 K (-193°C), the temperature of liquid nitrogen. As for the first sector, 1200 tonnes of liquid nitrogen will be used for the cool-down. In fact, the nitrogen circulates only at the surface in the ...

  10. Measuring the coolness of interactive products: the COOL questionnaire

    DEFF Research Database (Denmark)

    Bruun, Anders; Raptis, Dimitrios; Kjeldskov, Jesper;

    2016-01-01

    is the COOL questionnaire. We based the creation of the questionnaire on literature suggesting that perceived coolness is decomposed to outer cool (the style of a product) and inner cool (the personality characteristics assigned to it). In this paper, we focused on inner cool, and we identified 11 inner cool......, rebelliousness and usability. These factors and their underlying 16 question items comprise the COOL questionnaire. The whole process of creating the questionnaire is presented in detail in this paper and we conclude by discussing our work against related work on coolness and HCI....

  11. Invertible flexible matrices

    Science.gov (United States)

    Justino, Júlia

    2017-06-01

    Matrices with coefficients having uncertainties of type o (.) or O (.), called flexible matrices, are studied from the point of view of nonstandard analysis. The uncertainties of the afore-mentioned kind will be given in the form of the so-called neutrices, for instance the set of all infinitesimals. Since flexible matrices have uncertainties in their coefficients, it is not possible to define the identity matrix in an unique way and so the notion of spectral identity matrix arises. Not all nonsingular flexible matrices can be turned into a spectral identity matrix using Gauss-Jordan elimination method, implying that that not all nonsingular flexible matrices have the inverse matrix. Under certain conditions upon the size of the uncertainties appearing in a nonsingular flexible matrix, a general theorem concerning the boundaries of its minors is presented which guarantees the existence of the inverse matrix of a nonsingular flexible matrix.

  12. Global Sourcing Flexibility

    DEFF Research Database (Denmark)

    Ørberg Jensen, Peter D.; Petersen, Bent

    2013-01-01

    sourcing flexibility. Here we draw on prior research in the fields of organizational flexibility, international business and global sourcing as well as case examples and secondary studies. In the second part of the paper, we discuss the implications of global sourcing flexibility for firm strategy......Recent studies show that flexibility is a key concern for firms that engage in the global sourcing of services. In this conceptual paper, we seek to explore two central aspects of global sourcing flexibility: In the first part of the paper, we provide a definition of the construct of global...... and operations against the backdrop of the theory-based definition of the construct. We discuss in particular the importance of global sourcing flexibility for operational performance stability, and the trade-off between specialization benefits, emerging from location and service provider specialization, versus...

  13. Cool WISPs for stellar cooling excesses

    Energy Technology Data Exchange (ETDEWEB)

    Giannotti, Maurizio [Barry Univ., Miami Shores, FL (United States). Physical Sciences; Irastorza, Igor [Zaragoza Univ. (Spain). Dept. de Fisica Teorica; Redondo, Javier [Zaragoza Univ. (Spain). Dept. de Fisica Teorica; Max-Planck-Institut fuer Physik, Muenchen (Germany); Ringwald, Andreas [DESY Hamburg (Germany). Theory Group

    2015-12-15

    Several stellar systems (white dwarfs, red giants, horizontal branch stars and possibly the neutron star in the supernova remnant Cassiopeia A) show a preference for a mild non-standard cooling mechanism when compared with theoretical models. This exotic cooling could be provided by Weakly Interacting Slim Particles (WISPs), produced in the hot cores and abandoning the star unimpeded, contributing directly to the energy loss. Taken individually, these excesses do not show a strong statistical weight. However, if one mechanism could consistently explain several of them, the hint could be significant. We analyze the hints in terms of neutrino anomalous magnetic moments, minicharged particles, hidden photons and axion-like particles (ALPs). Among them, the ALP represents the best solution. Interestingly, the hinted ALP parameter space is accessible to the next generation proposed ALP searches, such as ALPS II and IAXO.

  14. Cool WISPs for stellar cooling excesses

    CERN Document Server

    Giannotti, Maurizio; Redondo, Javier; Ringwald, Andreas

    2015-01-01

    Several stellar systems (white dwarfs, red giants, horizontal branch stars and possibly the neutron star in the supernova remnant Cassiopeia A) show a preference for a mild non-standard cooling mechanism when compared with theoretical models. This exotic cooling could be provided by Weakly Interacting Slim Particles (WISPs), produced in the hot cores and abandoning the star unimpeded, contributing directly to the energy loss. Taken individually, these excesses do not show a strong statistical weight. However, if one mechanism could consistently explain several of them, the hint could be significant. We analyze the hints in terms of neutrino anomalous magnetic moments, minicharged particles, hidden photons and axion-like particles (ALPs). Among them, the ALP represents the best solution. Interestingly, the hinted ALP parameter space is accessible to the next generation proposed ALP searches, such as ALPS II and IAXO.

  15. Water-cooled electronics

    CERN Document Server

    Dumont, G; Righini, B

    2000-01-01

    LHC experiments demand on cooling of electronic instrumentation will be extremely high. A large number of racks will be located in underground caverns and counting rooms, where cooling by conventional climatisation would be prohibitively expensive. A series of tests on the direct water cooling of VMEbus units and of their standard power supplies is reported. A maximum dissipation of 60 W for each module and more than 1000 W delivered by the power supply to the crate have been reached. These values comply with the VMEbus specifications. (3 refs).

  16. Call centres: constructing flexibility

    OpenAIRE

    Arzbächer, Sandra; Holtgrewe, Ursula; Kerst, Christian

    2002-01-01

    "The development of call centres as a flexible interface between firms and their environments has been seen as exemplary or even symptomatic of flexible capitalism (Sennett 1998). We are going to point out that they do not just stand for organisational change but also for changes of institutions towards deregulation. Employers and managers hoped for gains of flexibility, decreasing labour costs, and market gains by an expanded 24-hour-service. Surveillance and control by flexib...

  17. Pneumatic flexible shaft couplings

    OpenAIRE

    2007-01-01

    Main effort of every design engineer is reduction of torsional oscillation in any mechanical system. At present this problem can be solved by means of a suitable modification of dynamic properties of flexible shaft couplings according to dynamics in the given systems. But the dynamic properties of nowadays-applied flexible couplings arenot unchangeable because of aging and fatigue processes occurring in flexible coupling elements. Result of this fact causes detuning of mechanical system. Taki...

  18. Advanced Liquid-Cooling Garment Using Highly Thermally Conductive Sheets

    Science.gov (United States)

    Ruemmele, Warren P.; Bue, Grant C.; Orndoff, Evelyne; Tang, Henry

    2010-01-01

    This design of the liquid-cooling garment for NASA spacesuits allows the suit to remove metabolic heat from the human body more effectively, thereby increasing comfort and performance while reducing system mass. The garment is also more flexible, with fewer restrictions on body motion, and more effectively transfers thermal energy from the crewmember s body to the external cooling unit. This improves the garment s performance in terms of the maximum environment temperature in which it can keep a crewmember comfortable. The garment uses flexible, highly thermally conductive sheet material (such as graphite), coupled with cooling water lines of improved thermal conductivity to transfer the thermal energy from the body to the liquid cooling lines more effectively. The conductive sheets can be layered differently, depending upon the heat loads, in order to provide flexibility, exceptional in-plane heat transfer, and good through-plane heat transfer. A metal foil, most likely aluminum, can be put between the graphite sheets and the external heat source/sink in order to both maximize through-plane heat transfer at the contact points, and to serve as a protection to the highly conductive sheets. Use of a wicking layer draws excess sweat away from the crewmember s skin and the use of an outer elastic fabric ensures good thermal contact of the highly conductive underlayers with the skin. This allows the current state of the art to be improved by having cooling lines that can be more widely spaced to improve suit flexibility and to reduce weight. Also, cooling liquid does not have to be as cold to achieve the same level of cooling. Specific areas on the human body can easily be targeted for greater or lesser cooling to match human physiology, a warmer external environment can be tolerated, and spatial uniformity of the cooling garment can be improved to reduce vasoconstriction limits. Elements of this innovation can be applied to other embodiments to provide effective heat

  19. Cooling Devices in Laser therapy.

    Science.gov (United States)

    Das, Anupam; Sarda, Aarti; De, Abhishek

    2016-01-01

    Cooling devices and methods are now integrated into most laser systems, with a view to protecting the epidermis, reducing pain and erythema and improving the efficacy of laser. On the basis of method employed, it can be divided into contact cooling and non-contact cooling. With respect to timing of irradiation of laser, the nomenclatures include pre-cooling, parallel cooling and post-cooling. The choice of the cooling device is dictated by the laser device, the physician's personal choice with respect to user-friendliness, comfort of the patient, the price and maintenance costs of the device. We hereby briefly review the various techniques of cooling, employed in laser practice.

  20. System and method for regulating EGR cooling using a rankine cycle

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Timothy C.; Morris, Dave

    2015-12-22

    This disclosure relates to a waste heat recovery (WHR) system and method for regulating exhaust gas recirculation (EGR) cooling, and more particularly, to a Rankine cycle WHR system and method, including a recuperator bypass arrangement to regulate EGR exhaust gas cooling for engine efficiency improvement and thermal management. This disclosure describes other unique bypass arrangements for increased flexibility in the ability to regulate EGR exhaust gas cooling.

  1. System and method for regulating EGR cooling using a Rankine cycle

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Timothy C.; Morris, Dave

    2017-08-29

    This disclosure relates to a waste heat recovery (WHR) system and method for regulating exhaust gas recirculation (EGR) cooling, and more particularly, to a Rankine cycle WHR system and method, including a recuperator bypass arrangement to regulate EGR exhaust gas cooling for engine efficiency improvement and thermal management. This disclosure describes other unique bypass arrangements for increased flexibility in the ability to regulate EGR exhaust gas cooling.

  2. LHC cooling gains ground

    CERN Multimedia

    Huillet-Miraton Catherine

    The nominal cryogenic conditions of 1.9 K have been achieved in sectors 5-6 and 7-8. This means that a quarter of the machine has reached the nominal conditions for LHC operation, having attained a temperature of below 2 K (-271°C), which is colder than interstellar space! Elsewhere, the cryogenic system in Sector 8-1 has been filled with liquid helium and cooled to 2K and will soon be available for magnet testing. Sectors 6-7 and 2-3 are being cooled down and cool-down operations have started in Sector 3-4. Finally, preparations are in hand for the cool-down of Sector 1-2 in May and of Sector 4-5, which is currently being consolidated. The LHC should be completely cold for the summer. For more information: http://lhc.web.cern.ch/lhc/Cooldown_status.htm.

  3. Why Exercise Is Cool

    Science.gov (United States)

    ... to Know About Puberty Train Your Temper Why Exercise Is Cool KidsHealth > For Kids > Why Exercise Is ... day and your body will thank you later! Exercise Makes Your Heart Happy You may know that ...

  4. Waveguide cooling system

    Science.gov (United States)

    Chen, B. C. J.; Hartop, R. W.

    1981-04-01

    An improved system is described for cooling high power waveguides by the use of cooling ducts extending along the waveguide, which minimizes hot spots at the flanges where waveguide sections are connected together. The cooling duct extends along substantially the full length of the waveguide section, and each flange at the end of the section has a through hole with an inner end connected to the duct and an opposite end that can be aligned with a flange hole in another waveguide section. Earth flange is formed with a drainage groove in its face, between the through hole and the waveguide conduit to prevent leakage of cooling fluid into the waveguide. The ducts have narrowed sections immediately adjacent to the flanges to provide room for the installation of fasteners closely around the waveguide channel.

  5. Warm and Cool Dinosaurs.

    Science.gov (United States)

    Mannlein, Sally

    2001-01-01

    Presents an art activity in which first grade students draw dinosaurs in order to learn about the concept of warm and cool colors. Explains how the activity also helped the students learn about the concept of distance when drawing. (CMK)

  6. Cooling of wood briquettes

    Directory of Open Access Journals (Sweden)

    Adžić Miroljub M.

    2013-01-01

    Full Text Available This paper is concerned with the experimental research of surface temperature of wood briquettes during cooling phase along the cooling line. The cooling phase is an important part of the briquette production technology. It should be performed with care, otherwise the quality of briquettes could deteriorate and possible changes of combustion characteristics of briquettes could happen. The briquette surface temperature was measured with an IR camera and a surface temperature probe at 42 sections. It was found that the temperature of briquette surface dropped from 68 to 34°C after 7 minutes spent at the cooling line. The temperature at the center of briquette, during the 6 hour storage, decreased to 38°C.

  7. Stacking with stochastic cooling

    Energy Technology Data Exchange (ETDEWEB)

    Caspers, Fritz E-mail: Fritz.Caspers@cern.ch; Moehl, Dieter

    2004-10-11

    Accumulation of large stacks of antiprotons or ions with the aid of stochastic cooling is more delicate than cooling a constant intensity beam. Basically the difficulty stems from the fact that the optimized gain and the cooling rate are inversely proportional to the number of particles 'seen' by the cooling system. Therefore, to maintain fast stacking, the newly injected batch has to be strongly 'protected' from the Schottky noise of the stack. Vice versa the stack has to be efficiently 'shielded' against the high gain cooling system for the injected beam. In the antiproton accumulators with stacking ratios up to 10{sup 5} the problem is solved by radial separation of the injection and the stack orbits in a region of large dispersion. An array of several tapered cooling systems with a matched gain profile provides a continuous particle flux towards the high-density stack core. Shielding of the different systems from each other is obtained both through the spatial separation and via the revolution frequencies (filters). In the 'old AA', where the antiproton collection and stacking was done in one single ring, the injected beam was further shielded during cooling by means of a movable shutter. The complexity of these systems is very high. For more modest stacking ratios, one might use azimuthal rather than radial separation of stack and injected beam. Schematically half of the circumference would be used to accept and cool new beam and the remainder to house the stack. Fast gating is then required between the high gain cooling of the injected beam and the low gain stack cooling. RF-gymnastics are used to merge the pre-cooled batch with the stack, to re-create free space for the next injection, and to capture the new batch. This scheme is less demanding for the storage ring lattice, but at the expense of some reduction in stacking rate. The talk reviews the 'radial' separation schemes and also gives some

  8. Cooling of electronic equipment

    DEFF Research Database (Denmark)

    A. Kristensen, Anders Schmidt

    2003-01-01

    Cooling of electronic equipment is studied. The design size of electronic equipment decrease causing the thermal density to increase. This affect the cooling which can cause for example failures of critical components due to overheating or thermal induced stresses. Initially a pin fin heat sink...... is considered as extruded profiles are inadequate for compact designs. An optimal pin fin shape and configuration is sought also taking manufacturing costs into consideration. Standard methods for geometrical modeling and thermal analysis are applied....

  9. Anomalous law of cooling

    OpenAIRE

    Lapas, Luciano C.; Ferreira, Rogelma M. S.; Oliveira, Fernando A.; Rubí, J. Miguel

    2014-01-01

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergo a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton's law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature ma...

  10. Cooling tower waste reduction

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, S.J.; Celeste, J.; Chine, R.; Scott, C.

    1998-05-01

    At Lawrence Livermore National Laboratory (LLNL), the two main cooling tower systems (central and northwest) were upgraded during the summer of 1997 to reduce the generation of hazardous waste. In 1996, these two tower systems generated approximately 135,400 lbs (61,400 kg) of hazardous sludge, which is more than 90 percent of the hazardous waste for the site annually. At both, wet decks (cascade reservoirs) were covered to block sunlight. Covering the cascade reservoirs reduced the amount of chemical conditioners (e.g. algaecide and biocide), required and in turn the amount of waste generated was reduced. Additionally, at the northwest cooling tower system, a sand filtration system was installed to allow cyclical filtering and backflushing, and new pumps, piping, and spray nozzles were installed to increase agitation. the appurtenance upgrade increased the efficiency of the cooling towers. The sand filtration system at the northwest cooling tower system enables operators to continuously maintain the cooling tower water quality without taking the towers out of service. Operational costs (including waste handling and disposal) and maintenance activities are compared for the cooling towers before and after upgrades. Additionally, the effectiveness of the sand filter system in conjunction with the wet deck covers (northwest cooling tower system), versus the cascade reservoir covers alone (south cooling tower south) is discussed. the overall expected return on investment is calculated to be in excess of 250 percent. this upgrade has been incorporated into the 1998 DOE complex-wide water conservation project being led by Sandia National Laboratory/Albuquerque.

  11. Cooling with Superfluid Helium

    CERN Document Server

    Lebrun, P

    2014-01-01

    The technical properties of helium II (‘superfluid’ helium) are presented in view of its applications to the cooling of superconducting devices, particularly in particle accelerators. Cooling schemes are discussed in terms of heat transfer performance and limitations. Large-capacity refrigeration techniques below 2 K are reviewed, with regard to thermodynamic cycles as well as process machinery. Examples drawn from existing or planned projects illustrate the presentation. Keywords: superfluid helium, cryogenics

  12. Laser cooling of solids

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, Richard I [Los Alamos National Laboratory; Sheik-bahae, Mansoor [UNM

    2008-01-01

    We present an overview of solid-state optical refrigeration also known as laser cooling in solids by fluorescence upconversion. The idea of cooling a solid-state optical material by simply shining a laser beam onto it may sound counter intuitive but is rapidly becoming a promising technology for future cryocooler. We chart the evolution of this science in rare-earth doped solids and semiconductors.

  13. Stacking with Stochastic Cooling

    CERN Document Server

    Caspers, Friedhelm

    2004-01-01

    Accumulation of large stacks of antiprotons or ions with the aid of stochastic cooling is more delicate than cooling a constant intensity beam. Basically the difficulty stems from the fact that the optimized gain and the cooling rate are inversely proportional to the number of particles seen by the cooling system. Therefore, to maintain fast stacking, the newly injected batch has to be strongly protected from the Schottky noise of the stack. Vice versa the stack has to be efficiently shielded against the high gain cooling system for the injected beam. In the antiproton accumulators with stacking ratios up to 105, the problem is solved by radial separation of the injection and the stack orbits in a region of large dispersion. An array of several tapered cooling systems with a matched gain profile provides a continuous particle flux towards the high-density stack core. Shielding of the different systems from each other is obtained both through the spatial separation and via the revolution frequencies (filters)....

  14. Alternative Room Cooling System

    Directory of Open Access Journals (Sweden)

    Md. Fazle Rabbi

    2015-06-01

    Full Text Available The rapidly growing population results in an increasing demand for much more residential and commercial buildings, which leads to vertical growth of the buildings and needs proper ventilation of those buildings. Natural air ventilation system is not sufficient for conventional building structures. Hence fans and air-conditioners are must to meet the requirement of proper ventilation as well as space conditioning. Globally building sector consumes largest energy in heating, cooling, ventilation and space conditioning. This load can be minimized by the application of solar chimney and modification in building structure for heating, cooling, ventilation and space conditioning. Passive solar cooling is a subject of interest to provide cooling by using the sun, a powerful energy source. This is done for ensuring human comfort in hot climates. ASHRAE (American Society of Heating, Refrigerating and Air Conditioning Engineers defines Comfort as ‘that state of mind which expresses satisfaction with the thermal environment.’ The present paper describes the development of a solar passive cooling system, which can provide thermal cooling throughout the summer season in hot and humid climates. The constructed passive system works on natural convection mode of air. Such system reduces the inside temperature of up to 5°C from the atmospheric temperature. Temperature can further be reduced by the judicious use of night ventilation.

  15. Special issue: Plasma Conversion

    NARCIS (Netherlands)

    Nozaki, T.; Bogaerts, A.; Tu, X.; van de Sanden, M. C. M.

    2017-01-01

    With growing concern of energy and environmental issues, the combination of plasma and heterogeneous catalysts receives special attention in greenhouse gas conversion, nitrogen fixation and hydrocarbon chemistry. Plasma gas conversion driven by renewable electricity is particularly important for the

  16. Comparing Social Stories™ to Cool versus Not Cool

    Science.gov (United States)

    Leaf, Justin B.; Mitchell, Erin; Townley-Cochran, Donna; McEachin, John; Taubman, Mitchell; Leaf, Ronald

    2016-01-01

    In this study we compared the cool versus not cool procedure to Social Stories™ for teaching various social behaviors to one individual diagnosed with autism spectrum disorder. The researchers randomly assigned three social skills to the cool versus not cool procedure and three social skills to the Social Stories™ procedure. Naturalistic probes…

  17. Reversibly Bistable Flexible Electronics

    KAUST Repository

    Alfaraj, Nasir

    2015-05-01

    Introducing the notion of transformational silicon electronics has paved the way for integrating various applications with silicon-based, modern, high-performance electronic circuits that are mechanically flexible and optically semitransparent. While maintaining large-scale production and prototyping rapidity, this flexible and translucent scheme demonstrates the potential to transform conventionally stiff electronic devices into thin and foldable ones without compromising long-term performance and reliability. In this work, we report on the fabrication and characterization of reversibly bistable flexible electronic switches that utilize flexible n-channel metal-oxide-semiconductor field-effect transistors. The transistors are fabricated initially on rigid (100) silicon substrates before they are peeled off. They can be used to control flexible batches of light-emitting diodes, demonstrating both the relative ease of scaling at minimum cost and maximum reliability and the feasibility of integration. The peeled-off silicon fabric is about 25 µm thick. The fabricated devices are transferred to a reversibly bistable flexible platform through which, for example, a flexible smartphone can be wrapped around a user’s wrist and can also be set back to its original mechanical position. Buckling and cyclic bending of such host platforms brings a completely new dimension to the development of flexible electronics, especially rollable displays.

  18. Organizational flexibility estimation

    OpenAIRE

    Komarynets, Sofia

    2013-01-01

    By the help of parametric estimation the evaluation scale of organizational flexibility and its parameters was formed. Definite degrees of organizational flexibility and its parameters for the Lviv region enterprises were determined. Grouping of the enterprises under the existing scale was carried out. Special recommendations to correct the enterprises behaviour were given.

  19. Flexible magnetoimpidence sensor

    KAUST Repository

    Kavaldzhiev, Mincho

    2015-05-01

    Recently, flexible electronic devices have attracted increasing interest, due to the opportunities they promise for new applications such as wearable devices, where the components are required to flex during normal use[1]. In this light, different magnetic sensors, like microcoil, spin valve, giant magnetoresistance (GMR), magnetoimpedance (MI), have been studied previously on flexible substrates.

  20. Efficient industrial burner control of a flexible burner management system; Effiziente industrielle Brennertechnik durch Einsatz flexibler Feuerungsautomaten

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, Ulrich; Saenger, Peter [Siemens AG, Rastatt (Germany)

    2012-02-15

    Compactness and flexibility of a burner control system is a very important issue. With a few types a wide range in different industrial applications should be covered. This paper presents different applications of a new burner control system: heating of cooling lines in glass industry, steam generation and air heating for a pistachio roastery and in grain dryers. (orig.)

  1. Measuring the coolness of interactive products: the COOL questionnaire

    DEFF Research Database (Denmark)

    Bruun, Anders; Raptis, Dimitrios; Kjeldskov, Jesper

    2016-01-01

    characteristics. These were used to create an initial pool of question items and 2236 participants were asked to assess 16 mobile devices. By performing exploratory and confirmatory factor analyses, we identified three factors that can measure the perceived inner coolness of interactive products: desirability...... is the COOL questionnaire. We based the creation of the questionnaire on literature suggesting that perceived coolness is decomposed to outer cool (the style of a product) and inner cool (the personality characteristics assigned to it). In this paper, we focused on inner cool, and we identified 11 inner cool...

  2. Chinese Conversation Structure

    Institute of Scientific and Technical Information of China (English)

    LIU Yan

    2016-01-01

    This paper aims to describe the features of Chinese conversation structure. Specifically speaking, the structure will be analyzed from the following four aspects:openings and pre-sequence, adjacency pairs, pre-closing and closing. Generally speak-ing, Chinese conversation structure is similar to English conversation structure. But still a lot of differences are found due to cul-tural factors.

  3. Flexible ferroelectric organic crystals

    Science.gov (United States)

    Owczarek, Magdalena; Hujsak, Karl A.; Ferris, Daniel P.; Prokofjevs, Aleksandrs; Majerz, Irena; Szklarz, Przemysław; Zhang, Huacheng; Sarjeant, Amy A.; Stern, Charlotte L.; Jakubas, Ryszard; Hong, Seungbum; Dravid, Vinayak P.; Stoddart, J. Fraser

    2016-10-01

    Flexible organic materials possessing useful electrical properties, such as ferroelectricity, are of crucial importance in the engineering of electronic devices. Up until now, however, only ferroelectric polymers have intrinsically met this flexibility requirement, leaving small-molecule organic ferroelectrics with room for improvement. Since both flexibility and ferroelectricity are rare properties on their own, combining them in one crystalline organic material is challenging. Herein, we report that trisubstituted haloimidazoles not only display ferroelectricity and piezoelectricity--the properties that originate from their non-centrosymmetric crystal lattice--but also lend their crystalline mechanical properties to fine-tuning in a controllable manner by disrupting the weak halogen bonds between the molecules. This element of control makes it possible to deliver another unique and highly desirable property, namely crystal flexibility. Moreover, the electrical properties are maintained in the flexible crystals.

  4. Flexible ferroelectric organic crystals

    Science.gov (United States)

    Owczarek, Magdalena; Hujsak, Karl A.; Ferris, Daniel P.; Prokofjevs, Aleksandrs; Majerz, Irena; Szklarz, Przemysław; Zhang, Huacheng; Sarjeant, Amy A.; Stern, Charlotte L.; Jakubas, Ryszard; Hong, Seungbum; Dravid, Vinayak P.; Stoddart, J. Fraser

    2016-01-01

    Flexible organic materials possessing useful electrical properties, such as ferroelectricity, are of crucial importance in the engineering of electronic devices. Up until now, however, only ferroelectric polymers have intrinsically met this flexibility requirement, leaving small-molecule organic ferroelectrics with room for improvement. Since both flexibility and ferroelectricity are rare properties on their own, combining them in one crystalline organic material is challenging. Herein, we report that trisubstituted haloimidazoles not only display ferroelectricity and piezoelectricity—the properties that originate from their non-centrosymmetric crystal lattice—but also lend their crystalline mechanical properties to fine-tuning in a controllable manner by disrupting the weak halogen bonds between the molecules. This element of control makes it possible to deliver another unique and highly desirable property, namely crystal flexibility. Moreover, the electrical properties are maintained in the flexible crystals. PMID:27734829

  5. Flexible Carbon Aerogels

    Directory of Open Access Journals (Sweden)

    Marina Schwan

    2016-09-01

    Full Text Available Carbon aerogels are highly porous materials with a large inner surface area. Due to their high electrical conductivity they are excellent electrode materials in supercapacitors. Their brittleness, however, imposes certain limitations in terms of applicability. In that context, novel carbon aerogels with varying degree of flexibility have been developed. These highly porous, light aerogels are characterized by a high surface area and possess pore structures in the micrometer range, allowing for a reversible deformation of the aerogel network. A high ratio of pore size to particle size was found to be crucial for high flexibility. For dynamic microstructural analysis, compression tests were performed in-situ within a scanning electron microscope allowing us to directly visualize the microstructural flexibility of an aerogel. The flexible carbon aerogels were found to withstand between 15% and 30% of uniaxial compression in a reversible fashion. These findings might stimulate further research and new application fields directed towards flexible supercapacitors and batteries.

  6. Video Format Conversion Chip Design

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper introduces the design of an IC, which is capable of cross-converting between various DTV standards, up to the HDTV resolution. A multi-phase FIR-based filtering algorithm is developed to perform the video scaling tasks. A dedicated fast SDRAM interface is designed in the system, providing an economical high-density storage for frame buffer. Meanwhile, film material pre-processing and frame/field rate up-conversion are also implemented in the memory control block. Finally, all the programmable parameters, such as the filter properties, can be set dynamically at run-time through an I2C interface, making the IC a very flexible system.This design has been verified through an FPGA emulation system. Subjective test of the output images indicates that the IC is a suitable and high quality solution to consumer applications.

  7. Elements of energy conversion

    CERN Document Server

    Russell, Charles R

    2013-01-01

    Elements of Energy Conversion brings together scattered information on the subject of energy conversion and presents it in terms of the fundamental thermodynamics that apply to energy conversion by any process. Emphasis is given to the development of the theory of heat engines because these are and will remain most important power sources. Descriptive material is then presented to provide elementary information on all important energy conversion devices. The book contains 10 chapters and opens with a discussion of forms of energy, energy sources and storage, and energy conversion. This is foll

  8. NGL data conversion system

    Science.gov (United States)

    Shoji, Masahiro; Horiuchi, Nobuyasu

    2005-06-01

    We are developing a NGL data conversion system for EPL, for LEEPL, and for EBDW, which is based on our established photomask data conversion system, PATACON PC-cluster. For EPL data conversion, it has SF division, Complementary division, Stitching, Proximity effect correction, Alignment mark insertion, EB stepper control data creation, and Mask inspection data creation. For LEEPL data conversion, it has Pattern checking, Complementary division, Stitching, Stress distortion correction, Alignment mark insertion, and Mask inspection data creation. For EB direct-writing data conversion, it has Proximity effect correction and Extraction of aperture pattern for cell projection exposure.

  9. The definition of cool

    Energy Technology Data Exchange (ETDEWEB)

    Nichiporuk, A.

    2005-05-01

    A new air cooling system at Agnico-Eagle's LaRonde mine, located in the Abitibi Region of Quebec is described. The new system serves a mine operating at 7,250 plus feet level. The system is installed at the surface; it utilizes ammonia to cool water, which cools the air. The system consists of four compressors which lower the temperature of the ammonia to minus 2 degrees C. Water, which at this temperature is 14 degrees, and ammonia pass through a plate heat exchanger simultaneously, however, without coming into contact with each other. The heat transfer that occurs causes the water's temperature to drop to 2 degrees C. The total volume of water cooled is 220 litres per second. The system is capable of reducing 636,000 cfm of air from 30 degrees C to 6 degrees C, to which 214,000 cfm of non-cooled air is added. This mixture, which is maintained at approximately 8 degrees C throughout the summer season, is sent underground to the deepest parts of the mine. The system runs from June to September, depending on the weather. In the evenings, when the temperature dips to around four to five degrees C, the water is shut down and side doors are opened to prevent the water from freezing.

  10. On analog simulation of ionization cooling of muons

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Ming

    2001-06-18

    Analog simulation, proposed here as an alternative approach for the study of ionization cooling of muons, is a scaled cooling experiment, using protons instead of muons as simulation particles. It is intended to be an effective and flexible, quick and inexpensive experiment for the understanding and validation of unprecedentedly complicated cooling physics, for the demonstration and optimization of various elaborated techniques for beam manipulation in 6D phase space. It can be done and perhaps should be done before the costly and time-consuming development of extremely challenging, muon-specific cooling technology. In a nutshell, the idea here is to build a toy machine in a playground of ideas, before staking the Imperial Guard of Napoleon into the bloody battlefield of Waterloo.

  11. Performance Evaluation of Photovoltaic Solar Panel Using Thermoelectric Cooling

    Directory of Open Access Journals (Sweden)

    Mr. Dinesh S. Borkar , Dr.Sunil.V.Prayagi, Ms. Jayashree Gotmare

    2014-01-01

    Full Text Available As a great potential renewable energy source, solar energy is becoming one of the most important energies in the future. Performance of PV panel decreases with increase in temperature of the PV panel. Hence, output power of PV module drops with rise in temperature, if heat is not removed. The cooling of PV modules would enhance the performance of PV panel. In order to cool this thermoelectric system is used. Hybridisation of PV module with thermoelectric modules used to increase the overall efficiency of the solar energy conversion system by keeping temperature constant within the limits. Model of hybrid combination of PV–Thermoelectric has been developed and study of thermoelectric has done to illustrate its usefulness in hybrid model of PV and thermoelectric modules. This paper shows the performance of PV panel through augmentation of thermoelectric cooling system to increase overall electric conversion efficiency of PV array.

  12. Aspects of Household Cooling Technology

    OpenAIRE

    Mrzyglod, Matthias; Holzer, Stefan

    2014-01-01

    Actually available household cooling appliances in the highest efficiency class may consume less then 10W average electrical power. To achieve such power consumptions special challenges for the cooling system had to overcome. The related cooling system design has to consider several effects, which arise from the corresponding low cooling capacity demand, start/stop cycles and additional power consumptions by control accessories. The lecture provides symptomatic aspects of cooling technology, ...

  13. Flexible nanocrystal-coated glass fibers for high-performance thermoelectric energy harvesting.

    Science.gov (United States)

    Liang, Daxin; Yang, Haoran; Finefrock, Scott W; Wu, Yue

    2012-04-11

    Recent efforts on the development of nanostructured thermoelectric materials from nanowires (Boukai, A. I.; et al. Nature 2008, 451, (7175), 168-171; Hochbaum, A. I.; et al. Nature 2008, 451, (7175), 163-167) and nanocrystals (Kim, W.; et al. Phys. Rev. Lett. 2006, 96, (4), 045901; Poudel, B.; et al. Science 2008, 320, (5876), 634-638; Scheele, M.; et al. Adv. Funct. Mater. 2009, 19, (21), 3476-3483; Wang, R. Y.; et al. Nano Lett. 2008, 8, (8), 2283-2288) show the comparable or superior performance to the bulk crystals possessing the same chemical compositions because of the dramatically reduced thermal conductivity due to phonon scattering at nanoscale surface and interface. Up to date, the majority of the thermoelectric devices made from these inorganic nanostructures are fabricated into rigid configuration. The explorations of truly flexible composite-based flexible thermoelectric devices (See, K. C.; et al. Nano Lett. 2010, 10, (11), 4664-4667) have thus far achieved much less progress, which in principle could significantly benefit the conversion of waste heat into electricity or the solid-state cooling by applying the devices to any kind of objects with any kind of shapes. Here we report an example using a scalable solution-phase deposition method to coat thermoelectric nanocrystals onto the surface of flexible glass fibers. Our investigation of the thermoelectric properties yields high performance comparable to the state of the art from the bulk crystals and proof-of-concept demonstration also suggests the potential of wrapping the thermoelectric fibers on the industrial pipes to improve the energy efficiency.

  14. Increasing the Efficiency of a Thermoelectric Generator Using an Evaporative Cooling System

    Science.gov (United States)

    Boonyasri, M.; Jamradloedluk, J.; Lertsatitthanakorn, C.; Therdyothin, A.; Soponronnarit, S.

    2016-11-01

    A system for reducing heat from the cold side of a thermoelectric (TE) power generator, based on the principle of evaporative cooling, is presented. An evaporative cooling system could increase the conversion efficiency of a TE generator. To this end, two sets of TE generators were constructed. Both TE generators were composed of five TE power modules. The cold and hot sides of the TE modules were fixed to rectangular fin heat sinks. The hot side heat sinks were inserted in a hot gas duct. The cold side of one set was cooled by the cooling air from a counter flow evaporative cooling system, whereas the other set was cooled by the parallel flow evaporative cooling system. The counter flow pattern had better performance than the parallel flow pattern. A comparison between the TE generator with and without an evaporative cooling system was made. Experimental results show that the power output increased by using the evaporative cooling system. This can significantly increase the TE conversion efficiency. The evaporative cooling system increased the power output of the TE generator from 22.9 W of ambient air flowing through the heat sinks to 28.6 W at the hot gas temperature of 350°C (an increase of about 24.8%). The present study shows the promising potential of using TE generators with evaporative cooling for waste heat recovery.

  15. Painful Flexible Flatfoot.

    Science.gov (United States)

    Sheikh Taha, Abdel Majid; Feldman, David S

    2015-12-01

    Flatfoot is commonly encountered by pediatric orthopedic surgeons and pediatricians. A paucity of literature exists on how to define a flatfoot. The absence of the medial arch with a valgus hindfoot is the hallmark of this pathology. Flatfoot can be flexible or rigid. This review focuses on the diagnosis and treatment of the flexible flatfoot. Most flatfeet are flexible and clinically asymptomatic, and warrant little intervention. If feet are symptomatic, treatment is needed. Most patients who require treatment improve with foot orthotics and exercises. Only feet resistant to conservative modalities are deemed surgical candidates. The presence of a tight heel cord is often found in patients who fail conservative management.

  16. Flexible Support Stanchion

    Energy Technology Data Exchange (ETDEWEB)

    Rudland, D.L.; /Fermilab

    1987-05-11

    Figure 1 shows the assembly drawing of the Central Calorimeter Cryostat Flexible Support Stanchion. Figures 2 and 3 show the Flexible Support STanchion in detail. These Stanchions support the cryostat safely, reduce the heat load to the cryostat from the ambient by a factor of more than ten, provide a spring like action that reduce the loads created by thermal contraction of the cryostat and position the cryostate accurately. Table 1 shows all of the details of the Flexible Support system for the C.C. Cryostat.

  17. Doppler cooling a microsphere

    CERN Document Server

    Barker, P F

    2010-01-01

    Doppler cooling the center-of-mass motion of an optically levitated microsphere via the velocity dependent scattering force from narrow whispering gallery mode (WGM) resonances is described. Light that is red detuned from the WGM resonance can be used to damp the center-of-mass motion in a process analogous to the Doppler cooling of atoms. Leakage of photons out of the microsphere when the incident field is near resonant with the narrow WGM resonance acts to damp the motion of the sphere. The scattering force is not limited by saturation, but can be controlled by the incident power. Cooling times on the order of seconds are calculated for a 20 micron diameter silica microsphere trapped within optical tweezers, with a Doppler temperature limit in the microKelvin regime.

  18. Natural radiative cooling

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.

    1979-01-01

    Natural radiative cooling at night was measured based on the surface-radiation spectrum after the heat balance of the surface exposed to the sun had been reradiated. A concept equivalent to the sky temperature and a concept useful for obtaining the net heat flux are discussed. The highest possible equilibrium temperature of the selective surface can be lowered; however, how to apply this practically is not yet known. A simple radiator, completely enclosed by a transparent screen, can produce a significant and inexpensive cooling effect. The results of experiments carried out in an area such as Padua, Italy, where the climate is not suitable for cooling purposes can still be predicted theoretically. The possibility of using the collector for heat collection during the day and as a radiator at night is indicated.

  19. Clean cooling; Saubere Kuehlung

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1998-07-01

    The round hybrid cooling towers which Balcke-Duerr GmbH is currently building for the 550-MW-IGCC-power-station of a refinery project on Sardinia have to meet particularly stringent requirements as seawater is used for cooling. The advantages are: Avoidance of visible plume with minimal energy consumption, optimal plume exit velocity and discharge, greatest possible stability of the plume column, avoidance of interference and recirculation, high operating reliability of the cooling tower. (orig.) [Deutsch] Derzeit werden die Kuehltuerme fuer ein 550-MW-IGCC-Kraftwerk einer Raffinierie auf Sardinien errichtet. Die Anforderungen an die Technik sind hoch, denn gekuehlt wird mit Seewasser. Zum Einsatz kommen Hybridrundkuehltuerme der Balcke-Duerr GmbH, Ratingen. Damit setzt das Unternehmen diesen Typ erstmals ausserhalb von Deutschland ein. (orig.)

  20. Monitoring Cray Cooling Systems

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, Don E [ORNL; Ezell, Matthew A [ORNL; Becklehimer, Jeff [Cray, Inc.; Donovan, Matthew J [ORNL; Layton, Christopher C [ORNL

    2014-01-01

    While sites generally have systems in place to monitor the health of Cray computers themselves, often the cooling systems are ignored until a computer failure requires investigation into the source of the failure. The Liebert XDP units used to cool the Cray XE/XK models as well as the Cray proprietary cooling system used for the Cray XC30 models provide data useful for health monitoring. Unfortunately, this valuable information is often available only to custom solutions not accessible by a center-wide monitoring system or is simply ignored entirely. In this paper, methods and tools used to harvest the monitoring data available are discussed, and the implementation needed to integrate the data into a center-wide monitoring system at the Oak Ridge National Laboratory is provided.

  1. Research on Cooling Effectiveness in Stepped Slot Film Cooling Vane

    Institute of Scientific and Technical Information of China (English)

    LI Yulong; WU Hong; ZHOU Feng; RONG Chengjun

    2016-01-01

    As one of the most important developments in air cooling technology for hot parts of the aero-engine,film cooling technology has been widely used.Film cooling hole structure exists mainly in areas that have high temperature,uneven cooling effectiveness issues when in actual use.The first stage turbine vanes of the aero-engine consume the largest portion of cooling air,thereby the research on reducing the amount of cooling air has the greatest potential.A new stepped slot film cooling vane with a high cooling effectiveness and a high cooling uniformity was researched initially.Through numerical methods,the affecting factors of the cooling effectiveness of a vane with the stepped slot film cooling structure were researched.This paper focuses on the cooling effectiveness and the pressure loss in different blowing ratio conditions,then the most reasonable and scientific structure parameter can be obtained by analyzing the results.The results show that 1.0 mm is the optimum slot width and 10.0 is the most reasonable blowing ratio.Under this condition,the vane achieved the best cooling result and the highest cooling effectiveness,and also retained a low pressure loss.

  2. Anomalous law of cooling.

    Science.gov (United States)

    Lapas, Luciano C; Ferreira, Rogelma M S; Rubí, J Miguel; Oliveira, Fernando A

    2015-03-14

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton's law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law of thermodynamics.

  3. Anomalous law of cooling

    Science.gov (United States)

    Lapas, Luciano C.; Ferreira, Rogelma M. S.; Rubí, J. Miguel; Oliveira, Fernando A.

    2015-03-01

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton's law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law of thermodynamics.

  4. Superconductor rotor cooling system

    Science.gov (United States)

    Gamble, Bruce B.; Sidi-Yekhlef, Ahmed; Schwall, Robert E.; Driscoll, David I.; Shoykhet, Boris A.

    2002-01-01

    A system for cooling a superconductor device includes a cryocooler located in a stationary reference frame and a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with a rotating reference frame in which the superconductor device is located. A method of cooling a superconductor device includes locating a cryocooler in a stationary reference frame, and transferring heat from a superconductor device located in a rotating reference frame to the cryocooler through a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with the rotating reference frame.

  5. A Cool Emperor Penguin

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    哇,这只帝企鹅的胸前居然有个心形!It’s cool!(乐天:没错,它的胸前少了这幺撮毛,应该会感觉挺凉快的)cool在这里可不是“凉快”的意思,而是“酷.帅气”的意思。我们《英语大王》的英文名字就叫English Cool Kids哦!(乐天拿出一副墨镜戴上:

  6. Rapid cooled lens cell

    Science.gov (United States)

    Stubbs, David M.; Hsu, Ike C.

    1991-12-01

    This paper describes the optomechanical design, thermal analysis, fabrication, and test evaluation processes followed in developing a rapid cooled, infrared lens cell. Thermal analysis was the key engineering discipline exercised in the design phase. The effect of thermal stress on the lens, induced by rapid cooling of the lens cell, was investigated. Features of this lens cell that minimized the thermal stress will be discussed in a dedicated section. The results of thermal analysis on the selected lens cell design and the selection of the flow channel design in the heat exchanger will be discussed. Throughout the paper engineering drawings, illustrations, analytical results, and photographs of actual hardware are presented.

  7. Gas cooled fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1972-06-01

    Although most of the development work on fast breeder reactors has been devoted to the use of liquid metal cooling, interest has been expressed for a number of years in alternative breeder concepts using other coolants. One of a number of concepts in which interest has been retained is the Gas-Cooled Fast Reactor (GCFR). As presently envisioned, it would operate on the uranium-plutonium mixed oxide fuel cycle, similar to that used in the Liquid Metal Fast Breeder Reactor (LMFBR), and would use helium gas as the coolant.

  8. Quantum thermodynamic cooling cycle

    CERN Document Server

    Palao, J P; Gordon, J M; Palao, Jose P.; Kosloff, Ronnie; Gordon, Jeffrey M.

    2001-01-01

    The quantum-mechanical and thermodynamic properties of a 3-level molecular cooling cycle are derived. An inadequacy of earlier models is rectified in accounting for the spontaneous emission and absorption associated with the coupling to the coherent driving field via an environmental reservoir. This additional coupling need not be dissipative, and can provide a thermal driving force - the quantum analog of classical absorption chillers. The dependence of the maximum attainable cooling rate on temperature, at ultra-low temperatures, is determined and shown to respect the recently-established fundamental bound based on the second and third laws of thermodynamics.

  9. Endosymbiotic flexibility associates with environmental sensitivity in scleractinian corals.

    Science.gov (United States)

    Putnam, Hollie M; Stat, Michael; Pochon, Xavier; Gates, Ruth D

    2012-11-07

    Flexibility in biological systems is seen as an important driver of macro-ecosystem function and stability. Spatially constrained endosymbiotic settings, however, are less studied, although environmental thresholds of symbiotic corals are linked to the function of their endosymbiotic dinoflagellate communities. Symbiotic flexibility is a hypothesized mechanism that corals may exploit to adapt to climate change. This study explores the flexibility of the coral-Symbiodinium symbiosis through quantification of Symbiodinium ITS2 sequence assemblages in a range of coral species and genera. Sequence assemblages are expressed as an index of flexibility incorporating phylogenetic divergence and relative abundance of Symbiodinium sequences recovered from the host. This comparative analysis reveals profound differences in the flexibility of corals for Symbiodinium, thereby classifying corals as generalists or specifists. Generalists such as Acropora and Pocillopora exhibit high intra- and inter-species flexibility in their Symbiodinium assemblages and are some of the most environmentally sensitive corals. Conversely, specifists such as massive Porites colonies exhibit low flexibility, harbour taxonomically narrow Symbiodinium assemblages, and are environmentally resistant corals. Collectively, these findings challenge the paradigm that symbiotic flexibility enhances holobiont resilience. This underscores the need for a deeper examination of the extent and duration of the functional benefits associated with endosymbiotic diversity and flexibility under environmental stress.

  10. Flexible Word Classes

    DEFF Research Database (Denmark)

    2013-01-01

    • First major publication on the phenomenon • Offers cross-linguistic, descriptive, and diverse theoretical approaches • Includes analysis of data from different language families and from lesser studied languages This book is the first major cross-linguistic study of 'flexible words', i.e. words...... that cannot be classified in terms of the traditional lexical categories Verb, Noun, Adjective or Adverb. Flexible words can - without special morphosyntactic marking - serve in functions for which other languages must employ members of two or more of the four traditional, 'specialised' word classes. Thus......, flexible words are underspecified for communicative functions like 'predicating' (verbal function), 'referring' (nominal function) or 'modifying' (a function typically associated with adjectives and e.g. manner adverbs). Even though linguists have been aware of flexible world classes for more than...

  11. Flexible displays, rigid designs?

    DEFF Research Database (Denmark)

    Hornbæk, Kasper

    2015-01-01

    Rapid technological progress has enabled a wide range of flexible displays for computing devices, but the user experience--which we're only beginning to understand--will be the key driver for successful designs....

  12. Flexibility in insulin prescription

    Directory of Open Access Journals (Sweden)

    Sanjay Kalra

    2016-01-01

    Full Text Available This communication explores the concept of flexibility, a propos insulin preparations and insulin regimes used in the management of type 2 diabetes. The flexibility of an insulin regime or preparation is defined as their ability to be injected at variable times, with variable injection-meal time gaps, in a dose frequency and quantum determined by shared decision making, with a minimal requirement of glucose monitoring and health professional consultation, with no compromise on safety, efficiency and tolerability. The relative flexibility of various basal, prandial and dual action insulins, as well as intensive regimes, is compared. The biopsychosocial model of health is used to assess the utility of different insulins while encouraging a philosophy of flexible insulin usage.

  13. Uranium conversion; Conversion de l`uranium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    This booklet is a presentation of the activities of the Comurhex company, created in 1971 and which became a 100% Cogema`s daughter company in 1992. The Comurhex company is in charge of the conversion of natural uranium into gaseous uranium hexafluoride (UF{sub 6}). The two steps of the conversion operation are performed in the Malvesi and Pierrelatte (France) industrial sites and represent 31% (14000 t/year) of the uranium conversion capacity of western countries. The refining and UF{sub 4} production (Malvesi) and the UF{sub 6} fabrication (Pierrelatte) processes are described. Comurhex is also one of the few companies in the world which produces UF{sub 6} from the uranium of spent fuels. (J.S.)

  14. COUPLING EFFECT OF FLEXIBLE JOINT AND FLEXIBLE LINK ON DYNAMIC SINGULARITY OF FLEXIBLE MANIPULATOR

    Institute of Scientific and Technical Information of China (English)

    GAO Zhihui; YUN Chao; BIAN Yushu

    2008-01-01

    The coupling effect of the flexible joint and the flexible link on the dynamic singularity of the flexible manipulator is addressed. Firstly, the dynamic equations of a flexible manipulator with a flexible joint and a flexible link are derived. Secondly, the relationship and property between the flexible joint and the flexible link are analyzed. It shows that the flexible joint's amplitude will increase abruptly, thereby the dynamic singularity occurs if the frequency of a flexible joint is near or equal to some natural frequency of a flexible link. Finally, some numerical simulations which will verify the correctness of the theoretical analysis, are carried out. The results are fundamental for the design of a flexible manipulator and for the avoidance of the dynamic singularity.

  15. Measure Guideline: Ventilation Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Springer, D. [Alliance for Residential Building Innovation (ARBI), David, CA (United States); Dakin, B. [Alliance for Residential Building Innovation (ARBI), David, CA (United States); German, A. [Alliance for Residential Building Innovation (ARBI), David, CA (United States)

    2012-04-01

    The purpose of this measure guideline is to provide information on a cost-effective solution for reducing cooling system energy and demand in homes located in hot-dry and cold-dry climates. This guideline provides a prescriptive approach that outlines qualification criteria, selection considerations, and design and installation procedures.

  16. Cooling of Neutron Stars

    Directory of Open Access Journals (Sweden)

    Grigorian H.

    2010-10-01

    Full Text Available We introduce the theoretical basis for modeling the cooling evolution of compact stars starting from Boltzmann equations in curved space-time. We open a discussion on observational verification of different neutron star models by consistent statistics. Particular interest has the question of existence of quark matter deep inside of compact object, which has to have a specific influence on the cooling history of the star. Besides of consideration of several constraints and features of cooling evolution, which are susceptible of being critical for internal structure of hot compact stars we have introduced a method of extraction of the mass distribution of the neutron stars from temperature and age data. The resulting mass distribution has been compared with the one suggested by supernove simulations. This method can be considered as an additional checking tool for the consistency of theoretical modeling of neutron stars. We conclude that the cooling data allowed existence of neutron stars with quark cores even with one-flavor quark matter.

  17. Elementary stochastic cooling

    Energy Technology Data Exchange (ETDEWEB)

    Tollestrup, A.V.; Dugan, G

    1983-12-01

    Major headings in this review include: proton sources; antiproton production; antiproton sources and Liouville, the role of the Debuncher; transverse stochastic cooling, time domain; the accumulator; frequency domain; pickups and kickers; Fokker-Planck equation; calculation of constants in the Fokker-Planck equation; and beam feedback. (GHT)

  18. ELECTRON COOLING FOR RHIC.

    Energy Technology Data Exchange (ETDEWEB)

    BEN-ZVI,I.

    2001-05-13

    The Accelerator Collider Department (CAD) at Brookhaven National Laboratory is operating the Relativistic Heavy Ion Collider (RHIC), which includes the dual-ring, 3.834 km circumference superconducting collider and the venerable AGS as the last part of the RHIC injection chain. CAD is planning on a luminosity upgrade of the machine under the designation RHIC II. One important component of the RHIC II upgrade is electron cooling of RHIC gold ion beams. For this purpose, BNL and the Budker Institute of Nuclear Physics in Novosibirsk entered into a collaboration aimed initially at the development of the electron cooling conceptual design, resolution of technical issues, and finally extend the collaboration towards the construction and commissioning of the cooler. Many of the results presented in this paper are derived from the Electron Cooling for RHIC Design Report [1], produced by the, BINP team within the framework of this collaboration. BNL is also collaborating with Fermi National Laboratory, Thomas Jefferson National Accelerator Facility and the University of Indiana on various aspects of electron cooling.

  19. Computers and conversation

    CERN Document Server

    Luff, Paul; Gilbert, Nigel G

    1986-01-01

    In the past few years a branch of sociology, conversation analysis, has begun to have a significant impact on the design of human*b1computer interaction (HCI). The investigation of human*b1human dialogue has emerged as a fruitful foundation for interactive system design.****This book includes eleven original chapters by leading researchers who are applying conversation analysis to HCI. The fundamentals of conversation analysis are outlined, a number of systems are described, and a critical view of their value for HCI is offered.****Computers and Conversation will be of interest to all concerne

  20. Laser cooling of a semiconductor by 40 kelvin.

    Science.gov (United States)

    Zhang, Jun; Li, Dehui; Chen, Renjie; Xiong, Qihua

    2013-01-24

    Optical irradiation accompanied by spontaneous anti-Stokes emission can lead to cooling of matter, in a phenomenon known as laser cooling, or optical refrigeration, which was proposed by Pringsheim in 1929. In gaseous matter, an extremely low temperature can be obtained in diluted atomic gases by Doppler cooling, and laser cooling of ultradense gas has been demonstrated by collisional redistribution of radiation. In solid-state materials, laser cooling is achieved by the annihilation of phonons, which are quanta of lattice vibrations, during anti-Stokes luminescence. Since the first experimental demonstration in glasses doped with rare-earth metals, considerable progress has been made, particularly in ytterbium-doped glasses or crystals: recently a record was set of cooling to about 110 kelvin from the ambient temperature, surpassing the thermoelectric Peltier cooler. It would be interesting to realize laser cooling in semiconductors, in which excitonic resonances dominate, rather than in systems doped with rare-earth metals, where atomic resonances dominate. However, so far no net cooling in semiconductors has been achieved despite much experimental and theoretical work, mainly on group-III-V gallium arsenide quantum wells. Here we report a net cooling by about 40 kelvin in a semiconductor using group-II-VI cadmium sulphide nanoribbons, or nanobelts, starting from 290 kelvin. We use a pump laser with a wavelength of 514 nanometres, and obtain an estimated cooling efficiency of about 1.3 per cent and an estimated cooling power of 180 microwatts. At 100 kelvin, 532-nm pumping leads to a net cooling of about 15 kelvin with a cooling efficiency of about 2.0 per cent. We attribute the net laser cooling in cadmium sulphide nanobelts to strong coupling between excitons and longitudinal optical phonons (LOPs), which allows the resonant annihilation of multiple LOPs in luminescence up-conversion processes, high external quantum efficiency and negligible background

  1. Flexible Hybrid Organic-Inorganic Perovskite Memory.

    Science.gov (United States)

    Gu, Chungwan; Lee, Jang-Sik

    2016-05-24

    Active research has been done on hybrid organic-inorganic perovskite materials for application to solar cells with high power conversion efficiency. However, this material often shows hysteresis, which is undesirable, shift in the current-voltage curve. The hysteresis may come from formation of defects and their movement in perovskite materials. Here, we utilize the defects in perovskite materials to be used in memory operations. We demonstrate flexible nonvolatile memory devices based on hybrid organic-inorganic perovskite as the resistive switching layer on a plastic substrate. A uniform perovskite layer is formed on a transparent electrode-coated plastic substrate by solvent engineering. Flexible nonvolatile memory based on the perovskite layer shows reproducible and reliable memory characteristics in terms of program/erase operations, data retention, and endurance properties. The memory devices also show good mechanical flexibility. It is suggested that resistive switching is done by migration of vacancy defects and formation of conducting filaments under the electric field in the perovskite layer. It is believed that organic-inorganic perovskite materials have great potential to be used in high-performance, flexible memory devices.

  2. Sorption cooling: a valid extension to passive cooling

    NARCIS (Netherlands)

    Doornink, D.J.; Burger, J.F.; Brake, ter H.J.M.

    2008-01-01

    Passive cooling has shown to be a very dependable cryogenic cooling method for space missions. Several missions employ passive radiators to cool down their delicate sensor systems for many years, without consuming power, without exporting vibrations or producing electromagnetic interference. So for

  3. Design Construction and Operation of a Supercritical Carbon Dioxide (sCO2) Loop for Investigation of Dry Cooling and Natural Circulation Potential for Use in Advanced Small Modular Reactors Utilizing sCO2 Power Conversion Cycles.

    Energy Technology Data Exchange (ETDEWEB)

    Middleton, Bobby D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rodriguez, Salvador B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Carlson, Matthew David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-11-01

    This report outlines the work completed for a Laboratory Directed Research and Development project at Sandia National Laboratories from October 2012 through September 2015. An experimental supercritical carbon dioxide (sCO 2 ) loop was designed, built, and o perated. The experimental work demonstrated that sCO 2 can be uti lized as the working fluid in an air - cooled, natural circulation configuration to transfer heat from a source to the ultimate heat sink, which is the surrounding ambient environment in most ca ses. The loop was also operated in an induction - heated, water - cooled configuration that allows for measurements of physical parameters that are difficult to isolate in the air - cooled configuration. Analysis included the development of two computational flu id dynamics models. Future work is anticipated to answer questions that were not covered in this project.

  4. Flexible energy harvesting from hard piezoelectric beams

    Science.gov (United States)

    Delnavaz, Aidin; Voix, Jérémie

    2016-11-01

    This paper presents design, multiphysics finite element modeling and experimental validation of a new miniaturized PZT generator that integrates a bulk piezoelectric ceramic onto a flexible platform for energy harvesting from the human body pressing force. In spite of its flexibility, the mechanical structure of the proposed device is simple to fabricate and efficient for the energy conversion. The finite element model involves both mechanical and piezoelectric parts of the device coupled with the electrical circuit model. The energy harvester prototype was fabricated and tested under the low frequency periodic pressing force during 10 seconds. The experimental results show that several nano joules of electrical energy is stored in a capacitor that is quite significant given the size of the device. The finite element model is validated by observing a good agreement between experimental and simulation results. the validated model could be used for optimizing the device for energy harvesting from earcanal deformations.

  5. Light trapping for flexible organic photovoltaics

    Science.gov (United States)

    Park, Yoonseok; Berger, Jana; Will, Paul-Anton; Soldera, Marcos; Glatz, Bernhard; Müller-Meskamp, Lars; Taretto, Kurt; Fery, Andreas; Lasagni, Andrés. Fabián.; Vandewal, Koen; Leo, Karl

    2016-09-01

    Here we investigate light trapping substrates and electrodes for enhancing the performance of organic photovoltaics (OPVs). Their power conversion efficiency (PCE) can be improved by a factor of 1.16 using laser patterned PET substrates and by a factor of 1.13 using commercial, structured display films. Furthermore, we prepare light trapping electrodes using as flexible conductive polymer with embedded TiO2 nanoparticles, improving the PCE by a factor of 1.08 as compared to a neat polymer electrode. However, nano-imprinted conductive polymer electrodes does not provide light trapping effect due to the small size (50 nm) of the structures. Moreover flexible OPV devices, integrating the above light trapping elements, show non-degraded performance after bending tests.

  6. Comments on Ionization Cooling Channel Characteristics

    CERN Document Server

    Neuffer, David

    2013-01-01

    Ionization cooling channels with a wide variety of characteristics and cooling properties are being developed. These channels can produce cooling performances that are largely consistent with the ionization cooling theory developed previously. In this paper we review ionization cooling theory, discuss its application to presently developing cooling channels, and discuss criteria for optimizing cooling.

  7. Comments on Ionization Cooling Channel Characteristics

    OpenAIRE

    Neuffer, David

    2013-01-01

    Ionization cooling channels with a wide variety of characteristics and cooling properties are being developed. These channels can produce cooling performances that are largely consistent with the ionization cooling theory developed previously. In this paper we review ionization cooling theory, discuss its application to presently developing cooling channels, and discuss criteria for optimizing cooling.

  8. Flexible magnetoimpedance sensor

    Energy Technology Data Exchange (ETDEWEB)

    Li, Bodong; Kavaldzhiev, Mincho N.; Kosel, Jürgen, E-mail: jurgen.kosel@kaust.edu.sa

    2015-03-15

    Flexible magnetoimpedance (MI) sensors fabricated using a NiFe/Cu/NiFe tri-layer on Kapton substrate have been studied. A customized flexible microstrip transmission line was employed to investigate the MI sensors's magnetic field and frequency responses and their dependence on the sensors's deflection. For the first time, the impedance characteristic is obtained through reflection coefficient analysis over a wide range of frequencies from 0.1 MHz to 3 GHz and for deflections ranging from zero curvature to a radius of 7.2 cm. The sensor element maintains a high MI ratio of up to 90% and magnetic sensitivity of up to 9.2%/Oe over different bending curvatures. The relationship between the curvature and material composition is discussed based on the magnetostriction effect and stress simulations. The sensor's large frequency range, simple fabrication process and high sensitivity provide a great potential for flexible electronics and wireless applications. - Highlights: • A flexible magnetoimpedance (MI) sensor is developed. • Studies are carried out using a flexible microstrip transmission line. • An MI ratio of up to 90% is obtained. • The effect of magnetostriction is studied.

  9. Thermoelectric Energy Conversion: Future Directions and Technology Development Needs

    Science.gov (United States)

    Fleurial, Jean-Pierre

    2007-01-01

    This viewgraph presentation reviews the process of thermoelectric energy conversion along with key technology needs and challenges. The topics include: 1) The Case for Thermoelectrics; 2) Advances in Thermoelectrics: Investment Needed; 3) Current U.S. Investment (FY07); 4) Increasing Thermoelectric Materials Conversion Efficiency Key Science Needs and Challenges; 5) Developing Advanced TE Components & Systems Key Technology Needs and Challenges; 6) Thermoelectrics; 7) 200W Class Lightweight Portable Thermoelectric Generator; 8) Hybrid Absorption Cooling/TE Power Cogeneration System; 9) Major Opportunities in Energy Industry; 10) Automobile Waste Heat Recovery; 11) Thermoelectrics at JPL; 12) Recent Advances at JPL in Thermoelectric Converter Component Technologies; 13) Thermoelectrics Background on Power Generation and Cooling Operational Modes; 14) Thermoelectric Power Generation; and 15) Thermoelectric Cooling.

  10. The Conversation Class

    Science.gov (United States)

    Jackson, Acy L.

    2012-01-01

    The conversation class occupies a unique place in the process of learning English as a second or foreign language. From the author's own experience in conducting special conversation classes with Persian-speaking adults, he has drawn up a number of simple but important guidelines, some of which he hopes may provide helpful suggestions for the…

  11. Content for Conversation Partners.

    Science.gov (United States)

    Olson, Kathleen

    2002-01-01

    Suggests that a good strategy for helping English language learners to develop communicative competence in English is by pairing them with native English speakers. In such conversation programs, conversation partners should be provided with topics and activities that incorporate the goals, interests, and experiences of the learners. Recommends…

  12. Canning Canned Conversations.

    Science.gov (United States)

    Gilmore, Michael P.; Daigaku, Sanyo

    Ways to improve the role-playing conversations found in most second language textbooks are outlined. It is argued that the conversations are often restrictive, dull, and repetitive, and students respond to them in kind. The teacher can make the target language used more interesting by creating new characters, situations, settings, or objectives.…

  13. Hydrothermal conversion of biomass

    NARCIS (Netherlands)

    Knezevic, Dragan

    2009-01-01

    This thesis presents research of hydrothermal conversion of biomass (HTC). In this process, hot compressed water (subcritical water) is used as the reaction medium. Therefore this technique is suitable for conversion of wet biomass/ waste streams. By working at high pressures, the evaporation of wat

  14. STOCHASTIC COOLING FOR BUNCHED BEAMS.

    Energy Technology Data Exchange (ETDEWEB)

    BLASKIEWICZ, M.

    2005-05-16

    Problems associated with bunched beam stochastic cooling are reviewed. A longitudinal stochastic cooling system for RHIC is under construction and has been partially commissioned. The state of the system and future plans are discussed.

  15. ALP hints from cooling anomalies

    CERN Document Server

    Giannotti, Maurizio

    2015-01-01

    We review the current status of the anomalies in stellar cooling and argue that, among the new physics candidates, an axion-like particle would represent the best option to account for the hinted additional cooling.

  16. Cooling devices in laser therapy

    Directory of Open Access Journals (Sweden)

    Anupam Das

    2016-01-01

    Full Text Available Cooling devices and methods are now integrated into most laser systems, with a view to protecting the epidermis, reducing pain and erythema and improving the efficacy of laser. On the basis of method employed, it can be divided into contact cooling and non-contact cooling. With respect to timing of irradiation of laser, the nomenclatures include pre-cooling, parallel cooling and post-cooling. The choice of the cooling device is dictated by the laser device, the physician′s personal choice with respect to user-friendliness, comfort of the patient, the price and maintenance costs of the device. We hereby briefly review the various techniques of cooling, employed in laser practice.

  17. Use of a temperature-initiated passive cooling system (TIPACS) for the modular high-temperature gas-cooled reactor cavity cooling system (RCCS)

    Energy Technology Data Exchange (ETDEWEB)

    Forsberg, C.W.; Conklin, J.; Reich, W.J.

    1994-04-01

    A new type of passive cooling system has been invented (Forsberg 1993): the Temperature-Initiated Passive Cooling System (TIPACS). The characteristics of the TIPACS potentially match requirements for an improved reactor-cavity-cooling system (RCCS) for the modular high-temperature gas-cooled reactor (MHTGR). This report is an initial evaluation of the TIPACS for the MHTGR with a Rankines (steam) power conversion cycle. Limited evaluations were made of applying the TIPACS to MHTGRs with reactor pressure vessel temperatures up to 450 C. These temperatures may occur in designs of Brayton cycle (gas turbine) and process heat MHTGRs. The report is structured as follows. Section 2 describes the containment cooling issues associated with the MHTGR and the requirements for such a cooling system. Section 3 describes TIPACS in nonmathematical terms. Section 4 describes TIPACS`s heat-removal capabilities. Section 5 analyzes the operation of the temperature-control mechanism that determines under what conditions the TIPACS rejects heat to the environment. Section 6 addresses other design and operational issues. Section 7 identifies uncertainties, and Section 8 provides conclusions. The appendixes provide the detailed data and models used in the analysis.

  18. Predictability of conversation partners

    CERN Document Server

    Takaguchi, Taro; Sato, Nobuo; Yano, Kazuo; Masuda, Naoki

    2011-01-01

    Recent developments in sensing technologies have enabled us to examine the nature of human social behavior in greater detail. By applying an information theoretic method to the spatiotemporal data of cell-phone locations, Song et al. (2010) found that human mobility patterns are remarkably predictable. Inspired by their work, we address a similar predictability question in a different kind of human social activity: conversation events. The predictability in the sequence of one's conversation partners is defined as the degree to which one's next conversation partner can be predicted given the current partner. We quantify this predictability by using the mutual information. We examine the predictability of conversation events for each individual using the longitudinal data of face-to-face interactions collected from two company offices in Japan. Each subject wears a name tag equipped with an infrared sensor node, and conversation events are marked when signals are exchanged between close sensor nodes. We find t...

  19. Political conversations on Facebook

    DEFF Research Database (Denmark)

    Sørensen, Mads P.

    2016-01-01

    Political conversations are according to theories on deliberative democracy essential to well-functioning democracies. Traditionally these conversations have taken place in face-to-face settings, in e.g. party meetings and town meetings. However, social media such as Facebook and Twitter offers new...... possibilities for online political conversations between citizens and politicians. This paper examines the presence on Facebook and Twitter of Members of the Danish national Parliament, the Folketing, and focusses on a quantitative mapping of the political conversation activities taking place in the threads...... following Facebook posts from Danish Members of Parliament (MPs). The paper shows that, in comparison with previous findings from other countries, Danish MPs have a relatively high degree of engagement in political conversations with citizens on Facebook – and that a large number of citizens follow MPs...

  20. Self pumping magnetic cooling

    Science.gov (United States)

    Chaudhary, V.; Wang, Z.; Ray, A.; Sridhar, I.; Ramanujan, R. V.

    2017-01-01

    Efficient thermal management and heat recovery devices are of high technological significance for innovative energy conservation solutions. We describe a study of a self-pumping magnetic cooling device, which does not require external energy input, employing Mn-Zn ferrite nanoparticles suspended in water. The device performance depends strongly on magnetic field strength, nanoparticle content in the fluid and heat load temperature. Cooling (ΔT) by ~20 °C and ~28 °C was achieved by the application of 0.3 T magnetic field when the initial temperature of the heat load was 64 °C and 87 °C, respectively. These experiments results were in good agreement with simulations performed with COMSOL Multiphysics. Our system is a self-regulating device; as the heat load increases, the magnetization of the ferrofluid decreases; leading to an increase in the fluid velocity and consequently, faster heat transfer from the heat source to the heat sink.

  1. Cooled particle accelerator target

    Science.gov (United States)

    Degtiarenko, Pavel V.

    2005-06-14

    A novel particle beam target comprising: a rotating target disc mounted on a retainer and thermally coupled to a first array of spaced-apart parallel plate fins that extend radially inwardly from the retainer and mesh without physical contact with a second array of spaced-apart parallel plate fins that extend radially outwardly from and are thermally coupled to a cooling mechanism capable of removing heat from said second array of spaced-apart fins and located within the first array of spaced-apart parallel fins. Radiant thermal exchange between the two arrays of parallel plate fins provides removal of heat from the rotating disc. A method of cooling the rotating target is also described.

  2. Magnetic entropy and cooling

    DEFF Research Database (Denmark)

    Hansen, Britt Rosendahl; Kuhn, Luise Theil; Bahl, Christian Robert Haffenden

    2010-01-01

    Some manifestations of magnetism are well-known and utilized on an everyday basis, e.g. using a refrigerator magnet for hanging that important note on the refrigerator door. Others are, so far, more exotic, such as cooling by making use of the magnetocaloric eect. This eect can cause a change...... or nitrogen liquefaction or for room-temperature cooling. The magnetocaloric eect can further be used to determine phase transition boundaries, if a change in the magnetic state occurs at the boundary.In this talk, I will introduce the magnetocaloric eect (MCE) and the two equations, which characterize...... in the temperature of a magnetic material when a magnetic eld is applied or removed. For many years, experimentalists have made use of dilute paramagnetic materials to achieve milliKelvin temperatures by use of the magnetocaloric eect. Also, research is done on materials, which might be used for hydrogen, helium...

  3. Cooling Floor AC Systems

    Science.gov (United States)

    Jun, Lu; Hao, Ding; Hong, Zhang; Ce, Gao Dian

    The present HVAC equipments for the residential buildings in the Hot-summer-and-Cold-winter climate region are still at a high energy consuming level. So that the high efficiency HVAC system is an urgently need for achieving the preset government energy saving goal. With its advantage of highly sanitary, highly comfortable and uniform of temperature field, the hot-water resource floor radiation heating system has been widely accepted. This paper has put forward a new way in air-conditioning, which combines the fresh-air supply unit and such floor radiation system for the dehumidification and cooling in summer or heating in winter. By analyze its advantages and limitations, we found that this so called Cooling/ Heating Floor AC System can improve the IAQ of residential building while keep high efficiency quality. We also recommend a methodology for the HVAC system designing, which will ensure the reduction of energy cost of users.

  4. High-performance and flexible thermoelectric films by screen printing solution-processed nanoplate crystals

    OpenAIRE

    Tony Varghese; Courtney Hollar; Joseph Richardson; Nicholas Kempf; Chao Han; Pasindu Gamarachchi; David Estrada; Mehta, Rutvik J.; Yanliang Zhang

    2016-01-01

    Screen printing allows for direct conversion of thermoelectric nanocrystals into flexible energy harvesters and coolers. However, obtaining flexible thermoelectric materials with high figure of merit ZT through printing is an exacting challenge due to the difficulties to synthesize high-performance thermoelectric inks and the poor density and electrical conductivity of the printed films. Here, we demonstrate high-performance flexible films and devices by screen printing bismuth telluride base...

  5. Flexible magnetoimpedance sensor

    KAUST Repository

    Li, Bodong

    2015-03-01

    Flexible magnetoimpedance (MI) sensors fabricated using a NiFe/Cu/NiFe tri-layer on Kapton substrate have been studied. A customized flexible microstrip transmission line was employed to investigate the MI sensors\\'s magnetic field and frequency responses and their dependence on the sensors\\'s deflection. For the first time, the impedance characteristic is obtained through reflection coefficient analysis over a wide range of frequencies from 0.1 MHz to 3 GHz and for deflections ranging from zero curvature to a radius of 7.2 cm. The sensor element maintains a high MI ratio of up to 90% and magnetic sensitivity of up to 9.2%/Oe over different bending curvatures. The relationship between the curvature and material composition is discussed based on the magnetostriction effect and stress simulations. The sensor\\'s large frequency range, simple fabrication process and high sensitivity provide a great potential for flexible electronics and wireless applications.

  6. Pneumatic flexible shaft couplings

    Directory of Open Access Journals (Sweden)

    Jaroslav HOMIŠIN

    2007-01-01

    Full Text Available Main effort of every design engineer is reduction of torsional oscillation in any mechanical system. At present this problem can be solved by means of a suitable modification of dynamic properties of flexible shaft couplings according to dynamics in the given systems. But the dynamic properties of nowadays-applied flexible couplings arenot unchangeable because of aging and fatigue processes occurring in flexible coupling elements. Result of this fact causes detuning of mechanical system. Taking into consideration the above-mentioned situation, we suggest for mechanical systems application of a newly developed pneumatic couplings that have constant characteristicfeatures during the whole current operation and thus they have a positive influence on the system running.

  7. Heating, ventilation and cooling

    CSIR Research Space (South Africa)

    Osburn, L

    2009-02-01

    Full Text Available content and is evaporated by the air stream with less moisture. Enthalpy wheels are more effective at transferring energy between the air streams as both sensible and latent heat is transferred. Ground-Coupled Heat Exchanger Ground-coupled heat... with high diurnal temperature variations. Evaporative Coolers Evaporative coolers work on the concept that the evaporation of water has a cooling effect on its immediate environment due to the latent heat that it absorbs in order to evaporate...

  8. Cooled Ion Frequency Standard.

    Science.gov (United States)

    2014-09-26

    when the cooling laser is turned off, the ions are heated by: (1) background gas collisions and (2) a plasma heating process which may be " resonant ...causes heating in our Penning traps. One way resonant particle transport is mediated is by misalignm.nt between the trap’s magnetic and electric axis...using computer solutions. The trap of Fig. 1 is noteworthy because although the inner surfaces of the trap are machined with simple conical cuts, the

  9. Designing structural supply chain flexibility

    OpenAIRE

    Mulinski, Ksawery Jan

    2012-01-01

    In a continuously changing business environment the role of supply chain flexibility is constantly increasing. A flexible supply chain can ensure survival in quickly changing market conditions as well as enable sustainable growth. This thesis explores the topic of supply chain flexibility with focus on structural flexibility due to scarcity of previous research in that area. The purpose of the research is to answer a question: how can companies design structural supply chain flexibility? In a...

  10. Improved cooling of electromagnetics by directed airflow

    Science.gov (United States)

    Fain, Adam Matthew

    The transformers in aircraft power conversion are often very heavy and represent a significant fuel or range penalty. Being thermally sized, improved cooling methods would allow downsizing and thereby reduced weight. Since the conductive paths in these metal "dense" devices are good, the controlling thermal resistance is typically the convective coefficient. The goal of this study was to optimize the convective air cooling across transformers by parametrically testing candidate shroud geometries to minimize average and hot spot surface temperatures with minimal fan power. A test set up was constructed that included a low velocity wind tunnel, fan, temperature and pressure sensors, DAQ system, and film heaters as well as the actual transformers. Experimental results from a low velocity wind tunnel were well predicted by CFD modeling, providing confidence in continued shroud development with only CFD or experimentally. Curved or bent types of shapes proved to be the most efficient shroud configurations in terms of maximizing heat transfer while reducing the energy requirement to achieve the desired level of cooling.

  11. Abundance analyses of cool extreme helium stars

    CERN Document Server

    Pandey, G; Lambert, D L; Jeffery, C S; Asplund, M; Pandey, Gajendra; Lambert, David L.; Asplund, Martin

    2001-01-01

    Extreme helium stars (EHe) with effective temperatures from 8000K to 13000K are among the coolest EHe stars and overlap the hotter R CrB stars in effective temperature. The cool EHes may represent an evolutionary link between the hot EHes and the R CrBs. Abundance analyses of four cool EHes are presented. To test for an evolutionary connection, the chemical compositions of cool EHes are compared with those of hot EHes and R CrBs. Relative to Fe, the N abundance of these stars is intermediate between those of hot EHes and R CrBs. For the R CrBs, the metallicity M derived from the mean of Si and S appears to be more consistent with the kinematics than that derived from Fe. When metallicity M derived from Si and S replaces Fe, the observed N abundances of EHes and R CrBs fall at or below the upper limit corresponding to thorough conversion of initial C and O to N. There is an apparent difference between the composition of R CrBs and EHes; the former having systematically higher [N/M] ratios. The material present...

  12. Electron Cooling of RHIC

    CERN Document Server

    Ben-Zvi, Ilan; Barton, Donald; Beavis, Dana; Blaskiewicz, Michael; Bluem, Hans; Brennan, Joseph M; Bruhwiler, David L; Burger, Al; Burov, Alexey; Burrill, Andrew; Calaga, Rama; Cameron, Peter; Chang, Xiangyun; Cole, Michael; Connolly, Roger; Delayen, Jean R; Derbenev, Yaroslav S; Eidelman, Yury I; Favale, Anthony; Fedotov, Alexei V; Fischer, Wolfram; Funk, L W; Gassner, David M; Hahn, Harald; Harrison, Michael; Hershcovitch, Ady; Holmes, Douglas; Hseuh Hsiao Chaun; Johnson, Peter; Kayran, Dmitry; Kewisch, Jorg; Kneisel, Peter; Koop, Ivan; Lambiase, Robert; Litvinenko, Vladimir N; MacKay, William W; Mahler, George; Malitsky, Nikolay; McIntyre, Gary; Meng, Wuzheng; Merminga, Lia; Meshkov, Igor; Mirabella, Kerry; Montag, Christoph; Nagaitsev, Sergei; Nehring, Thomas; Nicoletti, Tony; Oerter, Brian; Parkhomchuk, Vasily; Parzen, George; Pate, David; Phillips, Larry; Preble, Joseph P; Rank, Jim; Rao, Triveni; Rathke, John; Roser, Thomas; Russo, Thomas; Scaduto, Joseph; Schultheiss, Tom; Sekutowicz, Jacek; Shatunov, Yuri; Sidorin, Anatoly O; Skrinsky, Aleksander Nikolayevich; Smirnov, Alexander V; Smith, Kevin T; Todd, Alan M M; Trbojevic, Dejan; Troubnikov, Grigory; Wang, Gang; Wei, Jie; Williams, Neville; Wu, Kuo-Chen; Yakimenko, Vitaly; Zaltsman, Alex; Zhao, Yongxiang; ain, Animesh K

    2005-01-01

    We report progress on the R&D program for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This electron cooler is designed to cool 100 GeV/nucleon at storage energy using 54 MeV electrons. The electron source will be a superconducting RF photocathode gun. The accelerator will be a superconducting energy recovery linac. The frequency of the accelerator is set at 703.75 MHz. The maximum electron bunch frequency is 9.38 MHz, with bunch charge of 20 nC. The R&D program has the following components: The photoinjector and its photocathode, the superconducting linac cavity, start-to-end beam dynamics with magnetized electrons, electron cooling calculations including benchmarking experiments and development of a large superconducting solenoid. The photoinjector and linac cavity are being incorporated into an energy recovery linac aimed at demonstrating ampere class current at about 20 MeV. A Zeroth Order Design Report is in an advanced draft state, and can be found on the web at http://www.ags...

  13. Low mass integrated cooling

    CERN Document Server

    Mapelli, Alessandro

    2014-01-01

    Low mass on - detec tor cooling systems are being developed and stud ied by the Detector Technology group (PH - DT) in the CERN Physics Department in close collaboration with LHC and non - LHC experiments . Two approaches are currently being investigated. The first approach, for barrel configurations, consists in integrating the cooli ng apparatus in light mechanical structures support ing the detectors. In this case , the thermal management can be achieved either with light cooling pipes and thin plates or with a network of microchannels embedded in thin strips of silicon or polyimide . Both configuratio ns are being investigated in the context of the 2018 upgrade program of the ALICE Inner Tracking System (ITS). Moreover, it is also possible to use a s ilicon microchannel cooling device itself as structural support for the detectors and electronics. Such a configur ation has been adopted by the NA62 collaboration for the ir GigaTracKer (GTK) as well as by the LHCb collaboration for the 2018 major upgrade of...

  14. Simulation of Desiccant Cooling

    Directory of Open Access Journals (Sweden)

    Kamaruddin A.

    2017-06-01

    Full Text Available Desiccant cooling system has been an attractive topic for study lately, due to its environmentally friendly nature. It also consume less electricity and capable to be operated without refrigerant. A simulation study was conducted using 1.5 m long ducting equipped with one desiccant wheel, one sensible heat exchanger wheel, one evaporative cooling chamber and two blowers and one electric heater. The simulation study used 8.16 m/s primary air, the drying coefficient from desiccant wheel, k1=2.1 (1/s, mass transfer coefficient in evaporative cooling, k2=1.2 kg vapor/s, heat transfer coefficient in desiccant wheel, h1=4.5 W/m2 oC, and heat transfer coefficient in sensible heat exchanger wheel h2= 4.5 W/m2 oC. The simulation results show that the final temperature before entering into the air conditioning room was 25 oC and RH of 65 %, were in accordance with the Indonesian comfort index.

  15. Thin flexible intercalation anodes

    Energy Technology Data Exchange (ETDEWEB)

    Levy, S.C.; Cieslak, W.R.; Klassen, S.E.; Lagasse, R.R.

    1994-10-01

    Poly(acrylonitrile) fibers have been pyrolyzed under various conditions to form flexible carbon yarns capable of intercalating lithium ions. These fibers have also been formed into both woven and non woven cloths. Potentiostatic, potentiodynamic and galvanostatic tests have been conducted with these materials in several electrolytes. In some tests, a potential hold was used after each constant current charge and discharge. These tests have shown some of these flexible materials to reversibly intercalate lithium ions to levels that are suitable for use as a practical battery anode.

  16. Ultraefficient Cooling of Resonators: Beating Sideband Cooling with Quantum Control

    Science.gov (United States)

    Wang, Xiaoting; Vinjanampathy, Sai; Strauch, Frederick; Jacobs, Kurt

    2012-02-01

    There is presently a great deal of interest in cooling high-frequency micro- and nano-mechanical oscillators to their ground states. The present state of the art in cooling mechanical resonators is a version of sideband cooling, which was originally developed in the context of cooling trapped ions. Here we present a method based on quantum control that uses the same configuration as sideband cooling--coupling the resonator to be cooled to a second microwave (or optical) auxiliary resonator--but will cool significantly colder. This is achieved by applying optimal control and varying the strength of the coupling between the two resonators over a time on the order of the period of the mechanical resonator. As part of our analysis, we also obtain a method for fast, high-fidelity quantum information transfer between resonators.

  17. Energy Conversion Efficiency of Rainbow Shape Piezoelectric Transducer

    Institute of Scientific and Technical Information of China (English)

    LIU Xiangjian; CHEN Renwen; ZHU Liya

    2012-01-01

    With the aim to enhance the energy conversion efficiency of the rainbow shape piezoelectric transducer,an analysis model of energy conversion efficiency is established based on the elastic mechanics theory and piezoelectricity theory.It can be found that the energy conversion efficiency of the rainbow shape piezoelectric transducer mainly depends on its shape parameters and material properties from the analysis model.Simulation results show that there is an optimal length ratio to generate maximum energy conversion efficiency and the optimal length ratios and energy conversion efficiencies of beryllium bronze substrate transducer and steel substrate transducer are (0.65,2.21%) and (0.65,1.64%) respectively.The optimal thickness ratios and energy conversion efficiencies of beryllium bronze substrate transducer and steel substrate transducer are (1.16,2.56%) and (1.49,1.57%) respectively.With the increase of width ratio and initial curvature radius,both the energy conversion efficiencies decrease.Moreover,beryllium bronze flexible substrate transducer is superior to the steel flexible substrate transducer.

  18. Alpha and conversion electron spectroscopy of 238,239Pu and 241Am and alpha-conversion electron coincidence measurements

    Energy Technology Data Exchange (ETDEWEB)

    Dion, Michael P.; Miller, Brian W.; Warren, Glen A.

    2016-09-01

    A technique to determine the isotopics of a mixed actinide sample has been proposed by measuring the coincidence of the alpha particle during radioactive decay with the conversion electron (or Auger) emitted during the relaxation of the daughter isotope. This presents a unique signature to allow the deconvolution of isotopes that possess overlapping alpha particle energy. The work presented here are results of conversion electron spectroscopy of 241Am, 238Pu and 239Pu using a dual-stage peltier-cooled 25 mm2 silicon drift detector. A passivated ion implanted planar silicon detector provided measurements of alpha spectroscopy. The conversion electron spectra were evaluated from 20–55 keV based on fits to the dominant conversion electron emissions, which allowed the relative conversion electron emission intensities to be determined. These measurements provide crucial singles spectral information to aid in the coincident measurement approach.

  19. Cooling lubricants; Kuehlschmierstoffe

    Energy Technology Data Exchange (ETDEWEB)

    Pfeiffer, W. [Berufsgenossenschaftliches Inst. fuer Arbeitssicherheit, St. Augustin (Germany); Breuer, D. [Berufsgenossenschaftliches Inst. fuer Arbeitssicherheit, St. Augustin (Germany); Blome, H. [Berufsgenossenschaftliches Inst. fuer Arbeitssicherheit, St. Augustin (Germany); Deininger, C. [Berufsgenossenschaftliches Inst. fuer Arbeitssicherheit, St. Augustin (Germany); Hahn, J.U. [Berufsgenossenschaftliches Inst. fuer Arbeitssicherheit, St. Augustin (Germany); Kleine, H. [Berufsgenossenschaftliches Inst. fuer Arbeitssicherheit, St. Augustin (Germany); Nies, E. [Berufsgenossenschaftliches Inst. fuer Arbeitssicherheit, St. Augustin (Germany); Pflaumbaum, W. [Berufsgenossenschaftliches Inst. fuer Arbeitssicherheit, St. Augustin (Germany); Stockmann, R. [Berufsgenossenschaftliches Inst. fuer Arbeitssicherheit, St. Augustin (Germany); Willert, G. [Berufsgenossenschaftliches Inst. fuer Arbeitssicherheit, St. Augustin (Germany); Sonnenschein, G. [Maschinenbau- und Metall-Berufsgenossenschaft, Duesseldorf (Germany)

    1996-08-01

    As a rule, the base substances used are certain liquid hydrocarbons from mineral oils as well as from native and synthetic oils. Through the addition of further substances the cooling lubricant takes on the particular qualities required for the use in question. Employees working with cooling lubricants are exposed to various hazards. The assessment of the concentrations at the work station is carried out on the basis of existing technical rules for contact with hazardous substances. However, the application/implementation of compulsory investigation and supervision in accordance with these rules is made difficult by the fact that cooling lubricants are, as a rule, made up of complicated compound mixtures. In addition to protecting employees from exposure to mists and vapours from the cooling lubricants, protection for the skin is also of particular importance. Cooling lubricants should not, if at all possible, be brought into contact with the skin. Cleansing the skin and skin care is just as important as changing working clothes regularly, and hygiene and cleanliness at the workplace. Unavoidable emissions are to be immediately collected at the point where they arise or are released and safely disposed of. This means taking into account all sources of emissions. The programme presented in this report therefore gives a very detailed account of the individual protective measures and provides recommendations for the design of technical protection facilities. (orig./MG) [Deutsch] Als Basisstoffe dienen in der Regel bestimmte fluessige Kohlenwasserstoffverbindungen aus Mineraloelen sowie aus nativen oder synthetischen Oelen. Durch die Zugabe von weiteren Stoffen erlangt der Kuehlschmierstoff seine fuer den jeweiligen Anwendungsabfall geforderten Eigenschaften. Beschaeftigte, die mit Kuehlschmierstoffen umgehen, sind unterschiedliche Gefahren ausgesetzt. Die Beurteilung der Kuehlschmierstoffkonzentrationen in der Luft am Arbeitsplatz erfolgt auf der Grundlage bestehender

  20. Modelling home equity conversion loans with life insurance models

    Directory of Open Access Journals (Sweden)

    Baškot Bojan

    2013-01-01

    Full Text Available Home equity represents a reserve that can be used for providing additional money for its owners during their retirement. Life insurance models can be successfully applied to model home equity conversion loans. The home equity conversion loan is a financial product that provides a certain flexibility by using home equity as a resource for a quality life during retirement. Home equity conversion loans do not have a predetermined maturity date, as do conventional loans. But, like every loan, it must be repaid. One potential advantage of using a home equity conversion loan during tough financial times instead of some types of need-based assistance is that eligibility is straightforward. Home equity conversion loans can be useful tools in the process of pension system reform.

  1. High capacity 30 K remote helium cooling loop

    Science.gov (United States)

    Trollier, T.; Tanchon, J.; Icart, Y.; Ravex, A.

    2014-01-01

    Absolut System has built several 50 K remote helium cooling loops used as high capacity and very low vibration cooling source into large wavelength IR detectors electro-optical characterization test benches. MgB2 based superconducting electro-technical equipment's under development require also distributed high cooling power in the 20-30 K temperature range. Absolut System has designed, manufactured and tested a high capacity 30 K remote helium cooling loop. The equipment consists of a CRYOMECH AL325 type cooler, a CP830 type compressor package used as room temperature circulator and an intermediate LN2 bath cooling used between two recuperator heat exchangers (300 K-77 K and 77 K-20 K). A cooling capacity of 30 W @ 20 K or 80 W @ 30 K has been demonstrated on the application heat exchanger, with a 4-meter remote distance ensured by a specifically designed gas circulation flexible line. The design and the performance will be reported in this paper.

  2. Uranium conversion; Urankonvertering

    Energy Technology Data Exchange (ETDEWEB)

    Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina [Swedish Defence Research Agency (FOI), Stockholm (Sweden)

    2006-03-15

    FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF{sub 6} and UF{sub 4} are present require equipment that is made of corrosion resistant material.

  3. Uranium Conversion & Enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-06

    The isotopes of uranium that are found in nature, and hence in ‘fresh’ Yellowcake’, are not in relative proportions that are suitable for power or weapons applications. The goal of conversion then is to transform the U3O8 yellowcake into UF6. Conversion and enrichment of uranium is usually required to obtain material with enough 235U to be usable as fuel in a reactor or weapon. The cost, size, and complexity of practical conversion and enrichment facilities aid in nonproliferation by design.

  4. Solar energy conversion systems

    CERN Document Server

    Brownson, Jeffrey R S

    2013-01-01

    Solar energy conversion requires a different mind-set from traditional energy engineering in order to assess distribution, scales of use, systems design, predictive economic models for fluctuating solar resources, and planning to address transient cycles and social adoption. Solar Energy Conversion Systems examines solar energy conversion as an integrative design process, applying systems thinking methods to a solid knowledge base for creators of solar energy systems. This approach permits different levels of access for the emerging broad audience of scientists, engineers, architects, planners

  5. A Model for Conversation

    DEFF Research Database (Denmark)

    Ayres, Phil

    2012-01-01

    This essay discusses models. It examines what models are, the roles models perform and suggests various intentions that underlie their construction and use. It discusses how models act as a conversational partner, and how they support various forms of conversation within the conversational activity...... of design. Three distinctions are drawn through which to develop this discussion of models in an architectural context. An examination of these distinctions serves to nuance particular characteristics and roles of models, the modelling activity itself and those engaged in it....

  6. Energy conversion statics

    CERN Document Server

    Messerle, H K; Declaris, Nicholas

    2013-01-01

    Energy Conversion Statics deals with equilibrium situations and processes linking equilibrium states. A development of the basic theory of energy conversion statics and its applications is presented. In the applications the emphasis is on processes involving electrical energy. The text commences by introducing the general concept of energy with a survey of primary and secondary energy forms, their availability, and use. The second chapter presents the basic laws of energy conversion. Four postulates defining the overall range of applicability of the general theory are set out, demonstrating th

  7. Postoperative conversion disorder.

    Science.gov (United States)

    Afolabi, Kola; Ali, Sameer; Gahtan, Vivian; Gorji, Reza; Li, Fenghua; Nussmeier, Nancy A

    2016-05-01

    Conversion disorder is a psychiatric disorder in which psychological stress causes neurologic deficits. A 28-year-old female surgical patient had uneventful general anesthesia and emergence but developed conversion disorder 1 hour postoperatively. She reported difficulty speaking, right-hand numbness and weakness, and right-leg paralysis. Neurologic examination and imaging revealed no neuronal damage, herniation, hemorrhage, or stroke. The patient mentioned failing examinations the day before surgery and discontinuing her prescribed antidepressant medication, leading us to diagnose conversion disorder, with eventual confirmation by neuroimaging and follow-up examinations. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Conversion potential energy and its application to thermodynamic optimization

    Institute of Scientific and Technical Information of China (English)

    WU Jing; GUO ZengYuan

    2012-01-01

    In general,heat transfers can be classified into two categories according to the purposes of object heating or cooling and the heat to work conversion.Recently,a new physical quantity,entransy (or potential energy),was proposed to describe the ability of heat transfer with the former purpose.This paper addresses the concept of potential energy in terms of the heat transfer processes for the latter purpose,named the conversion potential energy.The physical meaning of this newly introduced concept is the potential energy for the heat to work conversion stored in the equivalent mass of heat (thermomass) derived on the basis of the Einstein's special theory of relativity.The dissipation of conversion potential energy occurs during the real irreversible heat to work conversion processes as a measure of the conversion irreversibility.Finally,a heat to work conversion problem of a heat exchanger group is provided to show that the minimum conversion potential energy dissipation rate can be used as an optimization criterion for the heat transfer performance with the purpose of the heat to work conversion.

  9. Flexible energy systems

    DEFF Research Database (Denmark)

    Lund, Henrik

    2003-01-01

    The paper discusses and analyses diffent national strategies and points out key changes in the energy system in order to achieve a system which can benefit from a high percentage of wind and CHP without having surplus production problems, introduced here as a flexible energy system....

  10. Flexible Classroom Furniture

    Science.gov (United States)

    Kim Hassell,

    2011-01-01

    Classroom design for the 21st-century learning environment should accommodate a variety of learning skills and needs. The space should be large enough so it can be configured to accommodate a number of learning activities. This also includes furniture that provides flexibility and accommodates collaboration and interactive work among students and…

  11. Flexible Language Interoperability

    DEFF Research Database (Denmark)

    Ekman, Torbjörn; Mechlenborg, Peter; Schultz, Ulrik Pagh

    2007-01-01

    of the language. In this paper, we present a highly flexible yet efficient approach to hosting multiple programming languages on an object-oriented virtual machine. Our approach is based on extending the interface of each class with language-specific wrapper methods, offering each language a tailored view...

  12. Flexible Mental Calculation.

    Science.gov (United States)

    Threlfall, John

    2002-01-01

    Suggests that strategy choice is a misleading characterization of efficient mental calculation and that teaching mental calculation methods as a whole is not conducive to flexibility. Proposes an alternative in which calculation is thought of as an interaction between noticing and knowledge. Presents an associated teaching approach to promote…

  13. Flexible cultural repertoires

    DEFF Research Database (Denmark)

    Lindegaard, Marie Rosenkrantz; Zimmermann, Francisca

    2017-01-01

    rejection of crime-involved youth. Young men who perform flexible cultural repertoires, by incorporating and shifting between gang and decent repertoires, experience low victimization due to their adaptation to crime-involved youth. Findings emphasize the importance of detailed investigations of the way...

  14. Flexible metal bellows

    CERN Multimedia

    1975-01-01

    A set of flexible metal bellows being fatigue-tested by repeated offset motion. Such bellows assemblies were used in the SPS vacuum system at places where , for instance, beam stoppers and collimators had to be moved frequently in and out of the beam path.

  15. Flexible Query Answering Systems

    DEFF Research Database (Denmark)

    This book constitutes the refereed proceedings of the 12th International Conference on Flexible Query Answering Systems, FQAS 2017, held in London, UK, in June 2017. The 21 full papers presented in this book together with 4 short papers were carefully reviewed and selected from 43 submissions...

  16. Laser Cooling of Molecular Anions

    CERN Document Server

    Yzombard, Pauline; Gerber, Sebastian; Doser, Michael; Comparat, Daniel

    2015-01-01

    We propose a scheme for laser cooling of negatively charged molecules. We briefly summarise the requirements for such laser cooling and we identify a number of potential candidates. A detailed computation study with C$\\_2^-$, the most studied molecular anion, is carried out. Simulations of 3D laser cooling in a gas phase show that this molecule could be cooled down to below 1 mK in only a few tens of milliseconds, using standard lasers. Sisyphus cooling, where no photo-detachment process is present, as well as Doppler laser cooling of trapped C$\\_2^-$, are also simulated. This cooling scheme has an impact on the study of cold molecules, molecular anions, charged particle sources and antimatter physics.

  17. Laser cooling of molecular anions.

    Science.gov (United States)

    Yzombard, Pauline; Hamamda, Mehdi; Gerber, Sebastian; Doser, Michael; Comparat, Daniel

    2015-05-29

    We propose a scheme for laser cooling of negatively charged molecules. We briefly summarize the requirements for such laser cooling and we identify a number of potential candidates. A detailed computation study with C_{2}^{-}, the most studied molecular anion, is carried out. Simulations of 3D laser cooling in a gas phase show that this molecule could be cooled down to below 1 mK in only a few tens of milliseconds, using standard lasers. Sisyphus cooling, where no photodetachment process is present, as well as Doppler laser cooling of trapped C_{2}^{-}, are also simulated. This cooling scheme has an impact on the study of cold molecules, molecular anions, charged particle sources, and antimatter physics.

  18. Process integration: Cooling water systems design

    CSIR Research Space (South Africa)

    Gololo, KV

    2010-10-01

    Full Text Available This paper presents a technique for grassroot design of cooling water system for wastewater minimization which incorporates the performances of the cooling towers involved. The study focuses mainly on cooling systems consisting of multiple cooling...

  19. Cooling water systems design using process integration

    CSIR Research Space (South Africa)

    Gololo, KV

    2010-09-01

    Full Text Available Cooling water systems are generally designed with a set of heat exchangers arranged in parallel. This arrangement results in higher cooling water flowrate and low cooling water return temperature thus reducing cooling tower efficiency. Previous...

  20. A cool 'win-win' for Matra

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, V. [Alstom, Budapest (Hungary)

    2007-07-15

    In 2004 the Matra plant management initiated a 60 M euro investment programme to increase the generating capacity of units 4 and 5 of the lignite fuelled plant and to give it greater flexibility. This has been achieved by adding a 30 MW natural gas-fired topping gas turbine to each of the 230 MW units, for commissioning by 2007. The power uprate meant the capacity of the dry-tower based cooling system was increased by 24 W for each unit. This has now undergone a major upgrade, involving addition of a wet cooling tower to create a 'hybrid' system. It is one of the largest such projects ever carried out, and the first involving a dry-tower cooling system of the Heller type. The result is increased competitiveness and efficiency, with a 250,000 t reduction in annual carbon dioxide emissions. 3 figs.

  1. Photonic multipartite entanglement conversion using nonlocal operations

    Science.gov (United States)

    Tashima, T.; Tame, M. S.; Özdemir, Ş. K.; Nori, F.; Koashi, M.; Weinfurter, H.

    2016-11-01

    We propose a simple setup for the conversion of multipartite entangled states in a quantum network with restricted access. The scheme uses nonlocal operations to enable the preparation of states that are inequivalent under local operations and classical communication, but most importantly does not require full access to the states. It is based on a flexible linear optical conversion gate that uses photons, which are ideally suited for distributed quantum computation and quantum communication in extended networks. In order to show the basic working principles of the gate, we focus on converting a four-qubit entangled cluster state to other locally inequivalent four-qubit states, such as the Greenberger-Horne-Zeilinger and symmetric Dicke states. We also show how the gate can be incorporated into extended graph state networks and can be used to generate variable entanglement and quantum correlations without entanglement but nonvanishing quantum discord.

  2. Adding flexibility to physician training.

    Science.gov (United States)

    Mahady, Suzanne E

    2011-05-02

    Demographic changes among junior doctors are driving demand for increased flexibility in advanced physician training, but flexible training posts are lacking. Suitable flexible training models include flexible full-time, job-share and part-time positions. Major barriers to establishing flexible training positions include difficulty in finding job-share partners, lack of funding for creating supernumerary positions, and concern over equivalence of educational quality compared with full-time training. Pilot flexible training positions should be introduced across the medical specialties and educational outcomes examined prospectively.

  3. Aggregating energy flexibilities under constraints

    DEFF Research Database (Denmark)

    Valsomatzis, Emmanouil; Pedersen, Torben Bach; Abello, Alberto

    2016-01-01

    The flexibility of individual energy prosumers (producers and/or consumers) has drawn a lot of attention in recent years. Aggregation of such flexibilities provides prosumers with the opportunity to directly participate in the energy market and at the same time reduces the complexity of scheduling...... the energy units. However, aggregated flexibility should support normal grid operation. In this paper, we build on the flex-offer (FO) concept to model the inherent flexibility of a prosumer (e.g., a single flexible consumption device such as a clothes washer). An FO captures flexibility in both time...

  4. Solar heating and cooling.

    Science.gov (United States)

    Duffie, J A; Beckman, W A

    1976-01-16

    We have adequate theory and engineering capability to design, install, and use equipment for solar space and water heating. Energy can be delivered at costs that are competitive now with such high-cost energy sources as much fuel-generated, electrical resistance heating. The technology of heating is being improved through collector developments, improved materials, and studies of new ways to carry out the heating processes. Solar cooling is still in the experimental stage. Relatively few experiments have yielded information on solar operation of absorption coolers, on use of night sky radiation in locations with clear skies, on the combination of a solar-operated Rankine engine and a compression cooler, and on open cycle, humidification-dehumidification systems. Many more possibilities for exploration exist. Solar cooling may benefit from collector developments that permit energy delivery at higher temperatures and thus solar operation of additional kinds of cycles. Improved solar cooling capability can open up new applications of solar energy, particularly for larger buildings, and can result in markets for retrofitting existing buildings. Solar energy for buildings can, in the next decade, make a significant contribution to the national energy economy and to the pocketbooks of many individual users. very large-aggregate enterprises in manufacture, sale, and installation of solar energy equipment can result, which can involve a spectrum of large and small businesses. In our view, the technology is here or will soon be at hand; thus the basic decisions as to whether the United States uses this resource will be political in nature.

  5. Structured luminescence conversion layer

    Science.gov (United States)

    Berben, Dirk; Antoniadis, Homer; Jermann, Frank; Krummacher, Benjamin Claus; Von Malm, Norwin; Zachau, Martin

    2012-12-11

    An apparatus device such as a light source is disclosed which has an OLED device and a structured luminescence conversion layer deposited on the substrate or transparent electrode of said OLED device and on the exterior of said OLED device. The structured luminescence conversion layer contains regions such as color-changing and non-color-changing regions with particular shapes arranged in a particular pattern.

  6. Managing social media conversations

    OpenAIRE

    2015-01-01

    The purpose of this thesis was to explore how companies can manage (monitor and control) social media conversations. Regardless of the companies’ presence in social media networks, they or their industry are constantly being discussed in social media. Therefore organisations should be present in social media, monitor and participate in conversations, in order to turn them into their benefit. There are software and services available to help in monitoring. Variety of tools and statistic de...

  7. Laser Cooling of Solids

    Science.gov (United States)

    2009-01-01

    observed in a range of glasses and crystals doped with Yb3+ (ZBLANP [19–22], ZBLAN [23,24], CNBZn [9,25] BIG [25, 26], KGd(WO4)2 [9], KY(WO4)2 [9], YAG [27...Yb3+-doped fluorozirconate glass ZBLAN , Phys. Rev. B 75, 144302 (2007). [40] C. W. Hoyt, Laser Cooling in Thulium-doped Solids, Ph. D. Thesis...date, optical refrigeration research has been confined to glasses and crystals doped with rare- earth elements and direct-band semiconductors such as

  8. Conversational flow promotes solidarity.

    Science.gov (United States)

    Koudenburg, Namkje; Postmes, Tom; Gordijn, Ernestine H

    2013-01-01

    Social interaction is fundamental to the development of various aspects of "we-ness". Previous research has focused on the role the content of interaction plays in establishing feelings of unity, belongingness and shared reality (a cluster of variables referred to as solidarity here). The present paper is less concerned with content, but focuses on the form of social interaction. We propose that the degree to which conversations flow smoothly or not is, of itself, a cue to solidarity. We test this hypothesis in samples of unacquainted and acquainted dyads who communicate via headsets. Conversational flow is disrupted by introducing a delay in the auditory feedback (vs. no delay). Results of three studies show that smoothly coordinated conversations (compared with disrupted conversations and a control condition) increase feelings of belonging and perceptions of group entitativity, independently of conversation content. These effects are driven by the subjective experience of conversational flow. Our data suggest that this process occurs largely beyond individuals' control. We conclude that the form of social interaction is a powerful cue for inferring group solidarity. Implications for the impact of modern communication technology on developing a shared social identity are discussed.

  9. Conversational flow promotes solidarity.

    Directory of Open Access Journals (Sweden)

    Namkje Koudenburg

    Full Text Available Social interaction is fundamental to the development of various aspects of "we-ness". Previous research has focused on the role the content of interaction plays in establishing feelings of unity, belongingness and shared reality (a cluster of variables referred to as solidarity here. The present paper is less concerned with content, but focuses on the form of social interaction. We propose that the degree to which conversations flow smoothly or not is, of itself, a cue to solidarity. We test this hypothesis in samples of unacquainted and acquainted dyads who communicate via headsets. Conversational flow is disrupted by introducing a delay in the auditory feedback (vs. no delay. Results of three studies show that smoothly coordinated conversations (compared with disrupted conversations and a control condition increase feelings of belonging and perceptions of group entitativity, independently of conversation content. These effects are driven by the subjective experience of conversational flow. Our data suggest that this process occurs largely beyond individuals' control. We conclude that the form of social interaction is a powerful cue for inferring group solidarity. Implications for the impact of modern communication technology on developing a shared social identity are discussed.

  10. Emissions-critical charge cooling using an organic rankine cycle

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Timothy C.; Nelson, Christopher R.

    2014-07-15

    The disclosure provides a system including a Rankine power cycle cooling subsystem providing emissions-critical charge cooling of an input charge flow. The system includes a boiler fluidly coupled to the input charge flow, an energy conversion device fluidly coupled to the boiler, a condenser fluidly coupled to the energy conversion device, a pump fluidly coupled to the condenser and the boiler, an adjuster that adjusts at least one parameter of the Rankine power cycle subsystem to change a temperature of the input charge exiting the boiler, and a sensor adapted to sense a temperature characteristic of the vaporized input charge. The system includes a controller that can determine a target temperature of the input charge sufficient to meet or exceed predetermined target emissions and cause the adjuster to adjust at least one parameter of the Rankine power cycle to achieve the predetermined target emissions.

  11. Optimization of thermoelectric performance in semiconducting polymers for understanding charge transport and flexible thermoelectric applications

    Science.gov (United States)

    Glaudell, Anne; Chabinyc, Michael

    2014-03-01

    Organic electronic materials have been widely considered for a variety of energy conversion applications, from photovoltaics to LEDs. Only very recently have organic materials been considered for thermoelectric applications - converting between temperature gradients and electrical potential. The intrinsic disorder in semiconducting polymers leads to an inherently low thermal conductivity, a key parameter in thermoelectric performance. The ability to solution deposit on flexible substrates opens up niche applications including personal cooling and conformal devices. Here work is presented on the electrical conductivity and thermopower of thin film semiconducting polymers, including P3HT and PBTTT-C14. Thermoelectric properties are explored over a wide range of conductivities, from nearly insulating to beyond 100 S/cm, enabled by employing different doping mechanisms, including molecular charge-transfer doping with F4TCNQ and vapor doping with a fluoroalkyl trichlorosilane (FTS). Temperature-dependent measurements suggest competing charge transport mechanisms, likely due to the mixed ordered/disordered character of these polymers. These results show promise for organic materials for thermoelectric applications, and recent results on thin film devices will also be presented.

  12. THE COOLING OF CORONAL PLASMAS. IV. CATASTROPHIC COOLING OF LOOPS

    Energy Technology Data Exchange (ETDEWEB)

    Cargill, P. J. [Space and Atmospheric Physics, The Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom); Bradshaw, S. J., E-mail: p.cargill@imperial.ac.uk [Department of Physics and Astronomy, Rice University, Houston, TX 77005 (United States)

    2013-07-20

    We examine the radiative cooling of coronal loops and demonstrate that the recently identified catastrophic cooling is due to the inability of a loop to sustain radiative/enthalpy cooling below a critical temperature, which can be >1 MK in flares, 0.5-1 MK in active regions, and 0.1 MK in long tenuous loops. Catastrophic cooling is characterized by a rapid fall in coronal temperature, while the coronal density changes by a small amount. Analytic expressions for the critical temperature are derived and show good agreement with numerical results. This effect considerably limits the lifetime of coronal plasmas below the critical temperature.

  13. Cooling Performance of an Impingement Cooling Device Combined with Pins

    Institute of Scientific and Technical Information of China (English)

    Dongliang QUAN; Songling LIU; Jianghai LI; Gaowen LIU

    2005-01-01

    Experimental study and one dimensional model analysis were conducted to investigate cooling performance of an integrated impingement and pin fin cooling device. A typical configuration specimen was made and tested in a large scale low speed closed-looped wind tunnel. Detailed two-dimensional contour maps of the temperature and cooling effectiveness were obtained for different pressure ratios and therefore different coolant flow-rates through the tested specimen. The experimental results showed that very high cooling effectiveness can be achieved by this cooling device with relatively small amount of coolant flow. Based on the theory of transpiration cooling in porous material, a one dimensional heat transfer model was established to analyze the effect of various parameters on cooling effectiveness. It was found from this model that the variation of heat transfer on the gas side, including heat transfer coefficient and film cooling effectiveness, of the specimen created much more effect on its cooling effectiveness than that of the coolant side. The predictions of the one-dimensional mode were compared and agreed well with the experimental data.

  14. FLEXIBLE GEIGER COUNTER

    Science.gov (United States)

    Richter, H.G.; Gillespie, A.S. Jr.

    1963-11-12

    A flexible Geiger counter constructed from materials composed of vinyl chloride polymerized with plasticizers or co-polymers is presented. The counter can be made either by attaching short segments of corrugated plastic sleeving together, or by starting with a length of vacuum cleaner hose composed of the above materials. The anode is maintained substantially axial Within the sleeving or hose during tube flexing by means of polystyrene spacer disks or an easily assembled polyethylene flexible cage assembly. The cathode is a wire spiraled on the outside of the counter. The sleeving or hose is fitted with glass end-pieces or any other good insulator to maintain the anode wire taut and to admit a counting gas mixture into the counter. Having the cathode wire on the outside of the counter substantially eliminates the objectional sheath effect of prior counters and permits counting rates up to 300,000 counts per minute. (AEC)

  15. Flexible Metasurface Holograms

    CERN Document Server

    Burch, James; Chen, Xianzhong; Di Falco, Andrea

    2016-01-01

    Metasurface holograms are typically fabricated on rigid substrates. Here we experimentally demonstrate broadband, flexible, conformable, helicity multiplexed metasurface holograms operating in the visible range, offering increased potential for real life out-of-the-lab applications. Two symmetrically distributed holographic images are obtained when circularly polarized light impinges on the reflective-type metasurface positioned on non- planar targets. The two off-axis images with high fidelity are interchangeable by controlling the helicity of incident light. Our metasurface features the arrangement of spatially varying gold nanorods on a flexible, conformable epoxy resist membrane to realize a Pancharatnam- Berry phase profile. These results pave the way to practical applications including polarization manipulation, beam steering, novel lenses, and holographic displays.

  16. Flexible Laser Metal Cutting

    DEFF Research Database (Denmark)

    Villumsen, Sigurd; Jørgensen, Steffen Nordahl; Kristiansen, Morten

    2014-01-01

    This paper describes a new flexible and fast approach to laser cutting called ROBOCUT. Combined with CAD/CAM technology, laser cutting of metal provides the flexibility to perform one-of-a-kind cutting and hereby realises mass production of customised products. Today’s laser cutting techniques...... possess, despite their wide use in industry, limitations regarding speed and geometry. Research trends point towards remote laser cutting techniques which can improve speed and geometrical freedom and hereby the competitiveness of laser cutting compared to fixed-tool-based cutting technology...... such as punching. This paper presents the concepts and preliminary test results of the ROBOCUT laser cutting technology, a technology which potentially can revolutionise laser cutting....

  17. Energy conversion in polyelectrolyte hydrogels

    Science.gov (United States)

    Olvera de La Cruz, Monica; Erbas, Aykut; Olvera de la Cruz Team

    Energy conversion and storage have been an active field of research in nanotechnology parallel to recent interests towards renewable energy. Polyelectrolyte (PE) hydrogels have attracted considerable attention in this field due to their mechanical flexibility and stimuli-responsive properties. Ideally, when a hydrogel is deformed, applied mechanical work can be converted into electrostatic, elastic and steric-interaction energies. In this talk, we discuss the results of our extensive molecular dynamics simulations of PE hydrogels. We demonstrate that, on deformation, hydrogels adjust their deformed state predominantly by altering electrostatic interactions between their charged groups rather than excluded-volume and bond energies. This is due to the hydrogel's inherent tendency to preserve electro-neutrality in its interior, in combination with correlations imposed by backbone charges. Our findings are valid for a wide range of compression ratios and ionic strengths. The electrostatic-energy alterations that we observe in our MD simulations may induce pH or redox-potential changes inside the hydrogels. The resulting energetic difference can be harvested, for instance, analogously to a Carnot engine, or facilitated for sensor applications. Center for Bio-inspired Energy Science (CBES).

  18. Flexible training under threat.

    Science.gov (United States)

    Houghton, Anita; Eaton, Jennifer

    2002-10-01

    As the number of women in medicine and the general demand for a better work-life balance rises, flexible training is an increasingly important mechanism for maintaining the medical workforce. The new pay deal, together with entrenched cultural attitudes, are potential threats. Ways forward include more substantive part-time posts, more part-time opportunities at consultant level, and using positive experiences as a way of tackling attitudes in the less accepting specialties.

  19. Flexible Land Administration

    DEFF Research Database (Denmark)

    Enemark, Stig

    2014-01-01

    Security of tenure is widely considered to be the missing piece of the puzzle when it comes to eradication of poverty. And, as explained in the previous issue of Geoinformatics, the European Union is now placing land rights at the heart of EU development policy. This article presents a way forwar...... in terms of building flexible and "fit-for-purpose" land administration systems in developing countries. This will ensure security of tenure for all and sustainable management of the use of land....

  20. More flexibility for DESY

    CERN Multimedia

    2003-01-01

    In the future, budgeting at DESY will be more efficient. The 16 associated research centers are to be granted a wider margin in matters of finance and human resources. The Budget Committee of the German Bundestag has agreed to abstain from mandatory staff appointments. The current pre-determined "job pyramid" will be replaced by a more flexible mechanism, so that the conclusion of fixed labor contracts can more closely follow the needs of research (1 page).

  1. Industrial Fuel Flexibility Workshop

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2006-09-01

    On September 28, 2006, in Washington, DC, ITP and Booz Allen Hamilton conducted a fuel flexibility workshop with attendance from various stakeholder groups. Workshop participants included representatives from the petrochemical, refining, food and beverage, steel and metals, pulp and paper, cement and glass manufacturing industries; as well as representatives from industrial boiler manufacturers, technology providers, energy and waste service providers, the federal government and national laboratories, and developers and financiers.

  2. Flexible Land Administration

    DEFF Research Database (Denmark)

    Enemark, Stig

    2014-01-01

    Security of tenure is widely considered to be the missing piece of the puzzle when it comes to eradication of poverty. And, as explained in the previous issue of Geoinformatics, the European Union is now placing land rights at the heart of EU development policy. This article presents a way forwar...... in terms of building flexible and "fit-for-purpose" land administration systems in developing countries. This will ensure security of tenure for all and sustainable management of the use of land....

  3. Flexible Data Link

    Science.gov (United States)

    2015-04-01

    reconfiguring the waveform characteristics (on-the-fly) based on the engagement environment. Therefore, flexibility was the highest priority in the design of...the aircraft to a ground antenna . Utilizing the threshold system requirements (100 km range), we calculate the multipath of the aircraft as it...approaches the ground antenna . Figure 3: Multipath scenario #1 The calculation of the reflected path (denoted as A + C in Figure 3) is found through the

  4. Electronic cooling using thermoelectric devices

    Energy Technology Data Exchange (ETDEWEB)

    Zebarjadi, M., E-mail: m.zebarjadi@rutgers.edu [Department of Mechanical and Aerospace Engineering, Rutgers University, Piscataway, New Jersey 08854 (United States); Institute of Advanced Materials, Devices, and Nanotechnology, Rutgers University, Piscataway, New Jersey 08854 (United States)

    2015-05-18

    Thermoelectric coolers or Peltier coolers are used to pump heat in the opposite direction of the natural heat flux. These coolers have also been proposed for electronic cooling, wherein the aim is to pump heat in the natural heat flux direction and from hot spots to the colder ambient temperature. In this manuscript, we show that for such applications, one needs to use thermoelectric materials with large thermal conductivity and large power factor, instead of the traditionally used high ZT thermoelectric materials. We further show that with the known thermoelectric materials, the active cooling cannot compete with passive cooling, and one needs to explore a new set of materials to provide a cooling solution better than a regular copper heat sink. We propose a set of materials and directions for exploring possible materials candidates suitable for electronic cooling. Finally, to achieve maximum cooling, we propose to use thermoelectric elements as fins attached to copper blocks.

  5. Optical stochastic cooling in Tevatron

    CERN Document Server

    Lebedev, V

    2012-01-01

    Intrabeam scattering is the major mechanism resulting in a growth of beam emittances and fast luminosity degradation in the Tevatron. As a result in the case of optimal collider operation only about 40% of antiprotons are used to the store end and the rest are discarded. Beam cooling is the only effective remedy to increase the particle burn rate and, consequently, the luminosity. Unfortunately neither electron nor stochastic cooling can be effective at the Tevatron energy and bunch density. Thus the optical stochastic cooling (OSC) is the only promising technology capable to cool the Tevatron beam. Possible ways of such cooling implementation in the Tevatron and advances in the OSC cooling theory are discussed in this paper. The technique looks promising and potentially can double the average Tevatron luminosity without increasing its peak value and the antiproton production.

  6. Flexible Ceramic-Metal Insulation Composite and Method of Making

    Science.gov (United States)

    Rasky, Daniel J. (Inventor); Sawko, Paul M. (Inventor); Kilodziej, Paul (Inventor); Kourtides, Demetrius A. (Inventor)

    1998-01-01

    A method for joining a woven flexible ceramic fabric and a thin metal sheet creating an integral metal surfaced flexible thermal protection article, which methods compress: placing multiple dots of high temperature metallic or fabric and the thin metal sheet in a random or organized pattern, with the proviso that the brazing material covers about 10% or less of the surface of one flat side of the metal sheet; heating the flexible ceramic fabric, brazing material and thin metal sheet for a predetermined period of time to integrally connect the same; and cooling the formed flexible article to ambient temperature. Preferably the flexible ceramic is selected from fibers comprising atoms of silicon, carbon, nitrogen, boron, oxygen or combinations thereof. The flexible thermal protection article produced is also part of the present invention. The thin metal sheet is comprised of titanium, aluminum, chromium, niobium or alloys or combinations thereof. The brazing material is selected from copper/silver or copper/gold or is a ceramic brazing or adhesive material.

  7. Cooling and entanglement of multimode graphene resonators via vacuum fluctuations

    Science.gov (United States)

    Ribeiro, Sofia; Terças, Hugo

    2017-08-01

    Sympathetic laser cooling of a single mode graphene membrane coupled to an atomic cloud interacting via Casimir-Polder forces has been recently proposed. Here, we extend this study to the effect of secondary graphene membrane whose frequency may be far or close to resonance. We show that if the two mechanical modes are close together, it is possible to simultaneously cool both modes. Conversely, if the two frequencies are set far apart, the secondary mode does not affect the cooling of the first one. We also study the entanglement properties of the steady-state using the logarithmic negativity. We show how stationary mechanical entanglement between two graphene sheets can be generated by means of vacuum fluctuations. Moreover, we find that, within feasible experimental parameters, large steady-state acoustomechanical entanglement, i.e. entanglement between the phononic and mechanical mode, {E}N≈ 5, can be generated.

  8. Designing structural supply chain flexibility

    NARCIS (Netherlands)

    Mulinski, Ksawery Jan

    2012-01-01

    In a continuously changing business environment the role of supply chain flexibility is constantly increasing. A flexible supply chain can ensure survival in quickly changing market conditions as well as enable sustainable growth. This thesis explores the topic of supply chain flexibility with focus

  9. Flexible Scheduling: Making the Transition

    Science.gov (United States)

    Creighton, Peggy Milam

    2008-01-01

    Citing literature that supports the benefits of flexible scheduling on student achievement, the author exhorts readers to campaign for flexible scheduling in their library media centers. She suggests tips drawn from the work of Graziano (2002), McGregor (2006) and Stripling (1997) for making a smooth transition from fixed to flexible scheduling:…

  10. Designing structural supply chain flexibility

    NARCIS (Netherlands)

    Mulinski, Ksawery Jan

    2012-01-01

    In a continuously changing business environment the role of supply chain flexibility is constantly increasing. A flexible supply chain can ensure survival in quickly changing market conditions as well as enable sustainable growth. This thesis explores the topic of supply chain flexibility with focus

  11. Electron Cooling Experiments in CSR

    CERN Document Server

    Xiaodong, Yang

    2011-01-01

    The six species heavy ion beam was accumulated with the help of electron cooling in the main ring of Cooler Storage Ring of Heavy Ion Research Facility in Lanzhou(HIRFL-CSR), the ion beam accumulation dependence on the parameters of cooler was investigated experimentally. The 400MeV/u 12C6+ and 200MeV/u 129Xe54+ was stored and cooled in the experimental ring CSRe, the cooling force was measured in different condition.

  12. To Be Cool or Uncool?

    Institute of Scientific and Technical Information of China (English)

    袁会珍

    2007-01-01

    The western world has always been divided into two types of people-the cool and the uncool. It is a division that __1__ in school. The cool kids are good at __2__. They are __3__ with the opposite sex. They are good-looking and people want to __4__ their style. They can do their homework but they don't make a big effort. That would __5__ be cool.

  13. Electron cooling experiments in CSR

    Institute of Scientific and Technical Information of China (English)

    PARKHOMCHUK; Vasily; REVA; Vladimir

    2011-01-01

    The six species heavy ion beam was accumulated with the help of electron cooling in the main ring of Cooler Storage Ring of Heavy Ion Research Facility in Lanzhou (HIRFL-CSR). The ion beam accumulation dependence on the parameters of cooler was investigated experimentally. The 400 MeV/u 12C6+ and 200 MeV/u 129Xe54+ were stored and cooled in the experimental ring CSRe, and the cooling force was measured in different conditions.

  14. Workshop 4 Converter cooling & recuperation

    Science.gov (United States)

    Iles, Peter; Hindman, Don

    1995-01-01

    Cooling the PV converter increases the overall TPV system efficiency, and more than offsets the losses incurred in providing cooling systems. Convective air flow methods may be sufficient, and several standard water cooling systems, including thermo-syphon radiators, capillary pumps or microchannel plates, are available. Recuperation is used to increase system efficiency, rather than to increase the emitter temperature. Recuperators operating at comparable high temperatures, such as in high temperature turbines have worked effectively.

  15. Stochastic cooling technology at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Pasquinelli, R.J. E-mail: pasquin@fnal.gov

    2004-10-11

    The first antiproton cooling systems were installed and commissioned at Fermilab in 1984-1985. In the interim period, there have been several major upgrades, system improvements, and complete reincarnation of cooling systems. This paper will present some of the technology that was pioneered at Fermilab to implement stochastic cooling systems in both the Antiproton Source and Recycler accelerators. Current performance data will also be presented.

  16. Boiler conversions for biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kinni, J. [Tampella Power Inc., Tampere (Finland)

    1996-12-31

    Boiler conversions from grate- and oil-fired boilers to bubbling fluidized bed combustion have been most common in pulp and paper industry. Water treatment sludge combustion, need for additional capacity and tightened emission limits have been the driving forces for the conversion. To accomplish a boiler conversion for biofuel, the lower part of the boiler is replaced with a fluidized bed bottom and new fuel, ash and air systems are added. The Imatran Voima Rauhalahti pulverized-peat-fired boiler was converted to bubbling fluidized bed firing in 1993. In the conversion the boiler capacity was increased by 10 % to 295 MWth and NO{sub x} emissions dropped. In the Kymmene Kuusankoski boiler, the reason for conversion was the combustion of high chlorine content biosludge. The emissions have been under general European limits. During the next years, the emission limits will tighten and the boilers will be designed for most complete combustion and compounds, which can be removed from flue gases, will be taken care of after the boiler. (orig.) 3 refs.

  17. Direct cooled power electronics substrate

    Science.gov (United States)

    Wiles, Randy H [Powell, TN; Wereszczak, Andrew A [Oak Ridge, TN; Ayers, Curtis W [Kingston, TN; Lowe, Kirk T [Knoxville, TN

    2010-09-14

    The disclosure describes directly cooling a three-dimensional, direct metallization (DM) layer in a power electronics device. To enable sufficient cooling, coolant flow channels are formed within the ceramic substrate. The direct metallization layer (typically copper) may be bonded to the ceramic substrate, and semiconductor chips (such as IGBT and diodes) may be soldered or sintered onto the direct metallization layer to form a power electronics module. Multiple modules may be attached to cooling headers that provide in-flow and out-flow of coolant through the channels in the ceramic substrate. The modules and cooling header assembly are preferably sized to fit inside the core of a toroidal shaped capacitor.

  18. Cooling clothing utilizing water evaporation

    DEFF Research Database (Denmark)

    Sakoi, Tomonori; Tominaga, Naoto; Melikov, Arsen Krikor

    2014-01-01

    We developed cooling clothing that utilizes water evaporation to cool the human body and has a mechanism to control the cooling intensity. Clean water was supplied to the outer surface of the T-shirt of the cooling clothing, and a small fan was used to enhance evaporation on this outer surface...... temperature ranging from 27.4 to 30.7 °C to establish a suitable water supply control method. A water supply control method that prevents water accumulation in the T-shirt and water dribbling was validated; this method is established based on the concept of the water evaporation capacity under the applied...

  19. Regeneratively Cooled Porous Media Jacket

    Science.gov (United States)

    Mungas, Greg (Inventor); Fisher, David J. (Inventor); London, Adam Pollok (Inventor); Fryer, Jack Merrill (Inventor)

    2013-01-01

    The fluid and heat transfer theory for regenerative cooling of a rocket combustion chamber with a porous media coolant jacket is presented. This model is used to design a regeneratively cooled rocket or other high temperature engine cooling jacket. Cooling jackets comprising impermeable inner and outer walls, and porous media channels are disclosed. Also disclosed are porous media coolant jackets with additional structures designed to transfer heat directly from the inner wall to the outer wall, and structures designed to direct movement of the coolant fluid from the inner wall to the outer wall. Methods of making such jackets are also disclosed.

  20. Fluid cooled electrical assembly

    Science.gov (United States)

    Rinehart, Lawrence E.; Romero, Guillermo L.

    2007-02-06

    A heat producing, fluid cooled assembly that includes a housing made of liquid-impermeable material, which defines a fluid inlet and a fluid outlet and an opening. Also included is an electrical package having a set of semiconductor electrical devices supported on a substrate and the second major surface is a heat sink adapted to express heat generated from the electrical apparatus and wherein the second major surface defines a rim that is fit to the opening. Further, the housing is constructed so that as fluid travels from the fluid inlet to the fluid outlet it is constrained to flow past the opening thereby placing the fluid in contact with the heat sink.

  1. ATLAS' major cooling project

    CERN Multimedia

    2005-01-01

    In 2005, a considerable effort has been put into commissioning the various units of ATLAS' complex cryogenic system. This is in preparation for the imminent cooling of some of the largest components of the detector in their final underground configuration. The liquid helium and nitrogen ATLAS refrigerators in USA 15. Cryogenics plays a vital role in operating massive detectors such as ATLAS. In many ways the liquefied argon, nitrogen and helium are the life-blood of the detector. ATLAS could not function without cryogens that will be constantly pumped via proximity systems to the superconducting magnets and subdetectors. In recent weeks compressors at the surface and underground refrigerators, dewars, pumps, linkages and all manner of other components related to the cryogenic system have been tested and commissioned. Fifty metres underground The helium and nitrogen refrigerators, installed inside the service cavern, are an important part of the ATLAS cryogenic system. Two independent helium refrigerators ...

  2. Photovoltaic solar energy conversion

    CERN Document Server

    Bauer, Gottfried H

    2015-01-01

    This concise primer on photovoltaic solar energy conversion invites readers to reflect on the conversion of solar light into energy at the most fundamental level and encourages newcomers to the field to help find meaningful answers on how photovoltaic solar energy conversion can work (better), eventually contributing to its ongoing advancement. The book is based on lectures given to graduate students in the Physics Department at the University of Oldenburg over the last two decades, yet also provides an easy-to-follow introduction for doctoral and postdoctoral students from related disciplines such as the materials sciences and electrical engineering. Inspired by classic textbooks in the field, it reflects the author’s own ideas on how to understand, visualize and eventually teach the microscopic physical mechanisms and effects, while keeping the text as concise as possible so as to introduce interested readers to the field and balancing essential knowledge with open questions.

  3. Direct conversion technology

    Energy Technology Data Exchange (ETDEWEB)

    Massier, P.F.; Back, L.H.; Ryan, M.A.; Fabris, G.

    1992-01-07

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC) and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1, 1991 through December 31, 1991. Research on AMTEC and on LMMHD was initiated during October 1987. Reports prepared on previous occasions (Refs. 1--5) contain descriptive and performance discussions of the following direct conversion concepts: thermoelectric, pyroelectric, thermionic, thermophotovoltaic, thermoacoustic, thermomagnetic, thermoelastic (Nitionol heat engine); and also, more complete descriptive discussions of AMTEC and LMMHD systems.

  4. Freely flowing conversations

    DEFF Research Database (Denmark)

    Aakjær, Marie Kirstejn; Andrade, David; Dexters, Peter

    2012-01-01

    on - and support “positive deviants” (Pascal, Sternin and Sternin) – courageous individuals and groups (inmates as well as staff) who transform conversations into new actions and behavioral traits that become beckons of an improved future. In the following we explore concrete examples of efforts at improving......Some would say this article is an impossibility - the authors being a project manager from the Department of Prisons an (ex) inmate and a Designer doing an industrial PhD in the prisons. We hope that others may see this article as an embodiment of how taking part in new conversations...... and in regards to rehabilitation efforts. In the context of prisons UDI is inspired by the complexity approach (Stacey 2005). We seek to facilitate freely flowing conversations between inmates, staff and managers – pushing the boundaries of existing norms, roles and beliefs. In the end however we rely...

  5. Air cooled absorption chillers for solar cooling applications

    Science.gov (United States)

    Biermann, W. J.; Reimann, R. C.

    1982-03-01

    The chemical composition of a 'best' absorption refrigerant system is identified, and those properties of the system necessary to design hot water operated, air cooled chilling equipment are determined. Air cooled chillers from single family residential sizes into the commercial rooftop size range are designed and operated.

  6. Predictability of Conversation Partners

    Science.gov (United States)

    Takaguchi, Taro; Nakamura, Mitsuhiro; Sato, Nobuo; Yano, Kazuo; Masuda, Naoki

    2011-08-01

    Recent developments in sensing technologies have enabled us to examine the nature of human social behavior in greater detail. By applying an information-theoretic method to the spatiotemporal data of cell-phone locations, [C. Song , ScienceSCIEAS0036-8075 327, 1018 (2010)] found that human mobility patterns are remarkably predictable. Inspired by their work, we address a similar predictability question in a different kind of human social activity: conversation events. The predictability in the sequence of one’s conversation partners is defined as the degree to which one’s next conversation partner can be predicted given the current partner. We quantify this predictability by using the mutual information. We examine the predictability of conversation events for each individual using the longitudinal data of face-to-face interactions collected from two company offices in Japan. Each subject wears a name tag equipped with an infrared sensor node, and conversation events are marked when signals are exchanged between sensor nodes in close proximity. We find that the conversation events are predictable to a certain extent; knowing the current partner decreases the uncertainty about the next partner by 28.4% on average. Much of the predictability is explained by long-tailed distributions of interevent intervals. However, a predictability also exists in the data, apart from the contribution of their long-tailed nature. In addition, an individual’s predictability is correlated with the position of the individual in the static social network derived from the data. Individuals confined in a community—in the sense of an abundance of surrounding triangles—tend to have low predictability, and those bridging different communities tend to have high predictability.

  7. External Cooling Coupled to Reduced Extremity Pressure Device

    Science.gov (United States)

    Kuznetz, Lawrence H.

    2011-01-01

    Although suited astronauts are currently cooled with a Liquid Cooled Ventilation Garment (LCVG), which can remove up to 85 percent of body heat, their effectiveness is limited because cooling must penetrate layers of skin, muscle, fat, bone, and tissue to reach the bloodstream, where its effect is prominent. Vasoconstriction further reduces the effectiveness by limiting arterial flow when exposed to cold (the frostbite response), resulting in a time constant on the order of 20 minutes from application to maximum effect. This delay can be crucial in severe exposure to hypo- or hyper-thermic conditions, compromising homeostasis. The purpose of this innovation is to provide a lightweight, effective means of delivering heat or cold from an external source directly to the bloodstream. The effectiveness of this ECCREP (External Cooling Coupled to Reduced Extremity Pressure) device is based on not having to penetrate layers of skin, muscle, fat, and tissue, thereby avoiding the thermal lag associated with their mass and heat capacity. This is accomplished by means of an outer boot operating at a slightly reduced pressure than the rest of the body, combined with an inner boot cooled or heated by an external source via water or chemicals. Heat transfer from the external source to the foot takes place by means of circulating water or flexible heat pipes.

  8. Converse Barrier Certificate Theorem

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2013-01-01

    This paper presents a converse barrier certificate theorem for a generic dynamical system.We show that a barrier certificate exists for any safe dynamical system defined on a compact manifold. Other authors have developed a related result, by assuming that the dynamical system has no singular...... points in the considered subset of the state space. In this paper, we redefine the standard notion of safety to comply with generic dynamical systems with multiple singularities. Afterwards, we prove the converse barrier certificate theorem and illustrate the differences between ours and previous work...

  9. Ocean wave energy conversion

    CERN Document Server

    McCormick, Michael E

    2007-01-01

    This volume will prove of vital interest to those studying the use of renewable resources. Scientists, engineers, and inventors will find it a valuable review of ocean wave mechanics as well as an introduction to wave energy conversion. It presents physical and mathematical descriptions of the nine generic wave energy conversion techniques, along with their uses and performance characteristics.Author Michael E. McCormick is the Corbin A. McNeill Professor of Naval Engineering at the U.S. Naval Academy. In addition to his timely and significant coverage of possible environmental effects associa

  10. Measuring and Comparing Energy Flexibilities

    DEFF Research Database (Denmark)

    Valsomatzis, Emmanouil; Hose, Katja; Pedersen, Torben Bach

    2015-01-01

    Flexibility in energy supply and demand becomes more and more important with increasing Renewable Energy Sources (RES) production and the emergence of the Smart Grid. So-called prosumers, i.e., entities that produce and/or consume energy, can offer their inherent flexibilities through so......-called demand response and thus help stabilize the energy markets. Thus, prosumer flexibility becomes valuable and the ongoing Danish project TotalFlex [1] explores the use of prosumer flexibility in the energy market using the concept of a flex-offer [2], which captures energy flexibilities in time and...... induced by time and amount individually, and by their com- bination. To this end, we introduce several flexibility measures that take into account the combined effect of time and energy on flex-offer flexibility and discuss their respective pros and cons through a number of realistic examples....

  11. Flexible Volumetric Structure

    Science.gov (United States)

    Cagle, Christopher M. (Inventor); Schlecht, Robin W. (Inventor)

    2014-01-01

    A flexible volumetric structure has a first spring that defines a three-dimensional volume and includes a serpentine structure elongatable and compressible along a length thereof. A second spring is coupled to at least one outboard edge region of the first spring. The second spring is a sheet-like structure capable of elongation along an in-plane dimension thereof. The second spring is oriented such that its in-plane dimension is aligned with the length of the first spring's serpentine structure.

  12. Flexible composite radiation detector

    Science.gov (United States)

    Cooke, D. Wayne; Bennett, Bryan L.; Muenchausen, Ross E.; Wrobleski, Debra A.; Orler, Edward B.

    2006-12-05

    A flexible composite scintillator was prepared by mixing fast, bright, dense rare-earth doped powdered oxyorthosilicate (such as LSO:Ce, LSO:Sm, and GSO:Ce) scintillator with a polymer binder. The binder is transparent to the scintillator emission. The composite is seamless and can be made large and in a wide variety of shapes. Importantly, the composite can be tailored to emit light in a spectral region that matches the optimum response of photomultipliers (about 400 nanometers) or photodiodes (about 600 nanometers), which maximizes the overall detector efficiency.

  13. Composite Flexible Blanket Insulation

    Science.gov (United States)

    Kourtides, Demetrius A. (Inventor); Pitts, William C. (Inventor); Goldstein, Howard E. (Inventor); Sawko, Paul M. (Inventor)

    1991-01-01

    Composite flexible multilayer insulation systems (MLI) were evaluated for thermal performance and compared with the currently used fibrous silica (baseline) insulation system. The systems described are multilayer insulations consisting of alternating layers of metal foil and scrim ceramic cloth or vacuum metallized polymeric films quilted together using ceramic thread. A silicon carbide thread for use in the quilting and the method of making it are also described. These systems are useful in providing lightweight insulation for a variety of uses, particularly on the surface of aerospace vehicles subject to very high temperatures during flight.

  14. Flexible plasma linear antenna

    Science.gov (United States)

    Zhao, Jiansen; Wang, Shengzheng; Wu, Huafeng; Liu, Yue; Chang, Yongmeng; Chen, Xinqiang

    2017-02-01

    In this work, we introduce a type of plasma antenna that was fabricated using flexible materials and excited using a 5-20 kHz alternating current (ac) power supply. The results showed that the antenna characteristics, including the impedance, the reflection coefficient (S11), the radiation pattern, and the gain, can be controlled rapidly and easily by varying both the discharge parameters and the antenna shapes. The scope for reconfiguration is greatly enhanced when the antenna shape is changed from a monopole to a helix configuration. Additionally, the antenna polarization can also be adjusted by varying the antenna shapes.

  15. Feasibility assessment of vacuum cooling followed by immersion vacuum cooling on water-cooked pork.

    Science.gov (United States)

    Dong, Xiaoguang; Chen, Hui; Liu, Yi; Dai, Ruitong; Li, Xingmin

    2012-01-01

    Vacuum cooling followed by immersion vacuum cooling was designed to cool water-cooked pork (1.5±0.05 kg) compared with air blast cooling (4±0.5°C, 2 m/s), vacuum cooling (10 mbar) and immersion vacuum cooling. This combined cooling method was: vacuum cooling to an intermediate temperature of 25°C and then immersion vacuum cooling with water of 10°C to the final temperature of 10°C. It was found that the cooling loss of this combined cooling method was significantly lower (Pvacuum cooling. This combined cooling was faster (Pvacuum cooling in terms of cooling rate. Moreover, the pork cooled by combined cooling method had significant differences (P<0.05) in water content, color and shear force. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Newton's Law of Cooling Revisited

    Science.gov (United States)

    Vollmer, M.

    2009-01-01

    The cooling of objects is often described by a law, attributed to Newton, which states that the temperature difference of a cooling body with respect to the surroundings decreases exponentially with time. Such behaviour has been observed for many laboratory experiments, which led to a wide acceptance of this approach. However, the heat transfer…

  17. Dialogues in the COOL Project

    NARCIS (Netherlands)

    Stalpers, S.I.P.; Kroeze, C.

    2013-01-01

    The Climate Options for the Long-term (COOL) Project is a participatory integrated assessment (PIA) comprising extensive dialogues at three levels: national, European and global. The objective of the COOL Project was to ‘develop strategic notions on how to achieve drastic reductions of greenhouse ga

  18. Be Cool, Man! / Jevgeni Levik

    Index Scriptorium Estoniae

    Levik, Jevgeni

    2005-01-01

    Järg 1995. aasta kriminaalkomöödiale "Tooge jupats" ("Get Shorty") : mängufilm "Be Cool, Chili Palmer on tagasi!" ("Be Cool") : režissöör F. Gary Gray, peaosades J. Travolta ja U. Thurman : USA 2005. Lisatud J. Travolta ja U. Thurmani lühiintervjuud

  19. Temperature initiated passive cooling system

    Science.gov (United States)

    Forsberg, Charles W.

    1994-01-01

    A passive cooling system for cooling an enclosure only when the enclosure temperature exceeds a maximum standby temperature comprises a passive heat transfer loop containing heat transfer fluid having a particular thermodynamic critical point temperature just above the maximum standby temperature. An upper portion of the heat transfer loop is insulated to prevent two phase operation below the maximum standby temperature.

  20. Be Cool, Man! / Jevgeni Levik

    Index Scriptorium Estoniae

    Levik, Jevgeni

    2005-01-01

    Järg 1995. aasta kriminaalkomöödiale "Tooge jupats" ("Get Shorty") : mängufilm "Be Cool, Chili Palmer on tagasi!" ("Be Cool") : režissöör F. Gary Gray, peaosades J. Travolta ja U. Thurman : USA 2005. Lisatud J. Travolta ja U. Thurmani lühiintervjuud

  1. Dew Point Evaporative Comfort Cooling

    Science.gov (United States)

    2012-11-01

    220 Figure 140. Water-cooled chilled water plant with primary/secondary...enough to buffer the space by carrying away solar loads in unoccupied volumes, such as ceiling plenums. For rooftop installations, where ceiling...and are significant for the three-month period and generally exceed 68%. Larger chilled water plants with water-cooled condensers can operate with

  2. Triatomic molecules laser-cooled

    Science.gov (United States)

    2017-06-01

    Molecules containing three atoms have been laser-cooled to ultracold temperatures for the first time. John Doyle and colleagues at Harvard University in the US used a technique called Sisyphus cooling to chill an ensemble of about a million strontium-monohydroxide molecules to 750 μK.

  3. Gender Differences in Conversation

    Institute of Scientific and Technical Information of China (English)

    陈媛媛

    2014-01-01

    Men and women applied language distinct from each other in many ways. The thesis gives an illustration of gender dif-ferences in conversation and different interpretive frames within which the discourse between men and women take place. More profoundly, it tries to explain them from perspective of socialization.

  4. Predicting AD conversion

    DEFF Research Database (Denmark)

    Liu, Yawu; Mattila, Jussi; Ruiz, Miguel �ngel Mu�oz

    2013-01-01

    To compare the accuracies of predicting AD conversion by using a decision support system (PredictAD tool) and current research criteria of prodromal AD as identified by combinations of episodic memory impairment of hippocampal type and visual assessment of medial temporal lobe atrophy (MTA) on MRI...

  5. Clinical Linguistics: Conversational Reflections

    Science.gov (United States)

    Crystal, David

    2013-01-01

    This is a report of the main points I made in an informal "conversation" with Paul Fletcher and the audience at the 14th ICPLA conference in Cork. The observations arose randomly, as part of an unstructured 1-h Q&A, so they do not provide a systematic account of the subject, but simply reflect the issues which were raised by the conference…

  6. Solar energy conversion

    OpenAIRE

    Crabtree, George W.; Lewis, Nathan S.

    2007-01-01

    If solar energy is to become a practical alternative to fossil fuels, we must have efficient ways to convert photons into electricity, fuel, and heat. The need for better conversion technologies is a driving force behind many recent developments in biology, materials, and especially nanoscience.

  7. Wavelength conversion devices

    DEFF Research Database (Denmark)

    Mikkelsen, Benny; Durhuus, Terji; Jørgensen, Carsten

    1996-01-01

    system requirements. The ideal wavelength converter should be transparent to the bit rate and signal format and provide an unchirped output signal with both a high extinction ratio and a large signal-to-noise ratio. It should allow conversion to both shorter and longer wavelengths with equal performance...

  8. Dissenting in Reflective Conversations

    DEFF Research Database (Denmark)

    Bjørn, Pernille; Boulus, Nina

    2011-01-01

    a methodological reflective approach that provides space for taking seriously uncertainties experienced in the field as these can be a catalyst for learning and sharpening our theoretical and empirical skills as action researchers. Through first-person inquiry, we investigate how our reflective conversations...

  9. Paralympics and conversion disorder

    National Research Council Canada - National Science Library

    David, Anthony S

    ...' for whose disorders are the most stigmatised. Psychiatry has a strong claim on this with mental illness generally regarded as among the most feared and least understood. 1 And within psychiatry there is a similar hierarchy such that patients with 'hysteria' or conversion disorder (CD) are those found to be least satisfying to treat and are least like...

  10. Converse Barrier Certificate Theorems

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2016-01-01

    This paper shows that a barrier certificate exists for any safe dynamical system. Specifically, we prove converse barrier certificate theorems for a class of structurally stable dynamical systems. Other authors have developed a related result by assuming that the dynamical system has neither sing...

  11. Conversational English Program, 1.

    Science.gov (United States)

    Instituto de Idiomas Yazigi, Sao Paulo (Brazil). Centro de Linguistica Aplicada.

    This first book of a conversational English program for adults contains an introductory section in Portuguese and exercises in English. The text centers around an English-speaking family from the United States that goes to live in Brazil. It contains color photographs with captions followed by exercises. The exercises are in English and involve…

  12. Conversational English Program, 2.

    Science.gov (United States)

    Instituto de Idiomas Yazigi, Sao Paulo (Brazil). Centro de Linguistica Aplicada.

    This second book of a conversational English program for adults contains an introductory section in Portuguese and exercises in English. The text centers around an English-speaking family from the United States that goes to live in Brazil. It contains color photographs with captions followed by exercises. The exercises are in English and involve…

  13. Development of a Single-Phase Thermosiphon for Cold Collection and Storage of Radiative Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ronggui [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhao, Dongliang [University of Colorado; Martini, Christine Elizabeth [University of Colorado; Jiang, Siyu [University of Colorado; Ma, Yaoguang [University of Colorado; Zhai, Yao [University of Colorado; Tan, Gang [University of Wyoming; Yin, Xiaobo [University of Colorado

    2017-09-19

    A single-phase thermosiphon is developed for cold collection and storage of radiative cooling. Compared to the conventional nocturnal radiative cooling systems that use an electric pump to drive the heat transfer fluid, the proposed single-phase thermosiphon uses the buoyancy force to drive heat transfer fluid. This solution does not require electricity, therefore improving the net gain of the radiative cooling system. A single-phase thermosiphon was built, which consists of a flat panel, a cold collection tank, a water return tube, and a water distribution tank. Considering that outdoor radiative cooling flux is constantly changing (i.e. uncontrollable), an indoor testing facility was developed to provide a controllable cooling flux (comparable to a radiative cooling flux of 100 W/m2) for the evaluation of thermosiphon performance. The testing apparatus is a chilled aluminum flat plate that has a controlled air gap separation relative to the flat panel surface of the thermosiphon to emulate radiative cooling. With an average of 105 W/m2 cooling flux, the 18 liters of water in the thermosiphon was cooled to an average temperature of 12.5 degrees C from an initial temperature of 22.2 degrees C in 2 h, with a cold collection efficiency of 96.8%. The results obtained have demonstrated the feasibility of using a single-phase thermosiphon for cold collection and storage of radiative cooling. Additionally, the effects of the thermosiphon operation conditions, such as tilt angle of the flat panel, initial water temperature, and cooling energy flux, on the performance have been experimentally investigated. Modular design of the single-phase thermosiphon gives flexibility for its scalability. A radiative cooling system with multiple thermosiphon modules is expected to play an important role in cooling buildings and power plant condensers.

  14. Evaluation of helium cooling for fusion divertors

    Energy Technology Data Exchange (ETDEWEB)

    Baxi, C.B.

    1993-09-01

    The divertors of future fusion reactors will have a power throughput of several hundred MW. The peak heat flux on the diverter surface is estimated to be 5 to 15 MW/m{sup 2} at an average heat flux of 2 MW/m{sup 2}. The divertors have a requirement of both minimum temperature (100{degrees}C) and maximum temperature. The minimum temperature is dictated by the requirement to reduce the absorption of plasma, and the maximum temperature is determined by the thermo-mechanical properties of the plasma facing materials. Coolants that have been considered for fusion reactors are water, liquid metals and helium. Helium cooling has been shown to be very attractive from safety and other considerations. Helium is chemically and neutronically inert and is suitable for power conversion. The challenges associated with helium cooling are: (1) Manifold sizes; (2) Pumping power; and (3) Leak prevention. In this paper the first two of the above design issues are addressed. A variety of heat transfer enhancement techniques are considered to demonstrate that the manifold sizes and the pumping power can be reduced to acceptable levels. A helium-cooled diverter module was designed and fabricated by GA for steady-state heat flux of 10 MW/m{sup 2}. This module was recently tested at Sandia National Laboratories. At an inlet pressure of 4 MPa, the module was tested at a steady-state heat flux of 10 MW/m{sup 2}. The pumping power required was less than 1% of the power removed. These results verified the design prediction.

  15. A novel electronic cooling concept

    Science.gov (United States)

    Ponnappan, R.; Beam, J. E.

    Advanced electrical power conditioning systems for the More Electric Aircraft Initiative involve high currents and high voltages with the attendant waste heat generation and cooling problems. The use of solid state switching devices such as MCTs for these systems will result in power dissipation of several hundred Watts per square centimeter. Conventional forced air or low velocity single phase fluid cooling is inadequate to handle the waste heat dissipation of these high power devices. More advanced and innovative methods of cooling which can use fluids available in the aircraft and also easy to package are sought. A new approach called 'venturi flow cooling concept' is described. It is shown that localized cooling up to 200 W/sq cm is possible at the venturi throat region where the MCTs can be mounted. PAO coolant with Pr = 56 at 40 C can be conveniently used in aircraft.

  16. Laser cooling to quantum degeneracy.

    Science.gov (United States)

    Stellmer, Simon; Pasquiou, Benjamin; Grimm, Rudolf; Schreck, Florian

    2013-06-28

    We report on Bose-Einstein condensation in a gas of strontium atoms, using laser cooling as the only cooling mechanism. The condensate is formed within a sample that is continuously Doppler cooled to below 1  μK on a narrow-linewidth transition. The critical phase-space density for condensation is reached in a central region of the sample, in which atoms are rendered transparent for laser cooling photons. The density in this region is enhanced by an additional dipole trap potential. Thermal equilibrium between the gas in this central region and the surrounding laser cooled part of the cloud is established by elastic collisions. Condensates of up to 10(5) atoms can be repeatedly formed on a time scale of 100 ms, with prospects for the generation of a continuous atom laser.

  17. Cooling off with physics

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, Chris [Unilever R and D (United Kingdom)

    2003-08-01

    You might think of ice cream as a delicious treat to be enjoyed on a sunny summer's day. However, to the ice-cream scientists who recently gathered in Thessaloniki in Greece for the 2nd International Ice Cream Symposium, it is a complex composite material. Ice cream consists of three dispersed phases: ice crystals, which have a mean size of 50 microns, air bubbles with a diameter of about 70 microns, and fat droplets with a size of 1 micron. These phases are held together by what is called the matrix - not a sci-fi film, but a viscous solution of sugars, milk proteins and polysaccharides. The microstructure, and hence the texture that you experience when you eat ice cream, is created in a freezing process that has remained fundamentally unchanged since the first ice-cream maker was patented in the 1840s. The ingredients - water, milk protein, fat, sugar, emulsifiers, stabilizers, flavours and a lot of air - are mixed together before being pasteurized and homogenized. They are then pumped into a cylinder that is cooled from the outside with a refrigerant. As the mixture touches the cylinder wall it freezes and forms ice crystals, which are quickly scraped off by a rotating blade. The blade is attached to a beater that disperses the ice crystals into the mixture. At the same time, air is injected and broken down into small bubbles by the shear that the beater generates. As the mixture passes along the cylinder, the number of ice crystals increases and its temperature drops. As a result, the viscosity of the mixture increases, so that more energy input is needed to rotate the beater. This energy is dissipated as heat, and when the ice cream reaches about -6 deg. C the energy input through the beater equals the energy removed as heat by the refrigerant. The process therefore becomes self-limiting and it is not possible to cool the ice cream any further. However, at -6 deg. C the microstructure is unstable. The ice cream therefore has to be removed from the freezer

  18. Simulating the Cooling Flow of Cool-Core Clusters

    CERN Document Server

    Li, Yuan

    2011-01-01

    We carry out high-resolution adaptive mesh refinement simulations of a cool core cluster, resolving the flow from Mpc scales down to pc scales. We do not (yet) include any AGN heating, focusing instead on cooling in order to understand how gas gets to the supermassive black hole (SMBH) at the center of the cluster. We find that, as the gas cools, the cluster develops a very flat temperature profile, undergoing a cooling catastrophe only in the central 10-100 pc of the cluster. Outside of this region, the flow is smooth, with no local cooling instabilities, and naturally produces very little low-temperature gas (below a few keV), in agreement with observations. The gas cooling in the center of the cluster rapidly forms a thin accretion disk. The amount of cold gas produced at the very center grows rapidly until a reasonable estimate of the resulting AGN heating rate (assuming even a moderate accretion efficiency) would overwhelm cooling. We argue that this naturally produces a thermostat which links the coolin...

  19. Asymmetric Flexible Supercapacitor Stack

    Directory of Open Access Journals (Sweden)

    Leela Mohana Reddy A

    2008-01-01

    Full Text Available AbstractElectrical double layer supercapacitor is very significant in the field of electrical energy storage which can be the solution for the current revolution in the electronic devices like mobile phones, camera flashes which needs flexible and miniaturized energy storage device with all non-aqueous components. The multiwalled carbon nanotubes (MWNTs have been synthesized by catalytic chemical vapor deposition technique over hydrogen decrepitated Mischmetal (Mm based AB3alloy hydride. The polymer dispersed MWNTs have been obtained by insitu polymerization and the metal oxide/MWNTs were synthesized by sol-gel method. Morphological characterizations of polymer dispersed MWNTs have been carried out using scanning electron microscopy (SEM, transmission electron microscopy (TEM and HRTEM. An assymetric double supercapacitor stack has been fabricated using polymer/MWNTs and metal oxide/MWNTs coated over flexible carbon fabric as electrodes and nafion®membrane as a solid electrolyte. Electrochemical performance of the supercapacitor stack has been investigated using cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy.

  20. 46 CFR 153.432 - Cooling systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cooling systems. 153.432 Section 153.432 Shipping COAST... Control Systems § 153.432 Cooling systems. (a) Each cargo cooling system must have an equivalent standby... cooling system. (b) Each tankship that has a cargo tank with a required cooling system must have a manual...

  1. Tool for economic and environmental analysis of hybrid plants for district cooling and district heating - 'District cooling 2.0'. Final report and user guide; Vaerktoej til oekonomisk og miljoemaessig analyse af hybridanlaeg til fjernkoeling og fjernvarme. Fjernkoel 2.0. Slutrapport og brugermanual

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-03-15

    The purpose of the tool is to help bring district cooling solutions into consideration by facilitating rapid technical / economic and environmental analysis of district cooling solutions - also with heat pump operation. The tool is a screening tool intended for specific cases with actual data from reality. The tool can analyze the simultaneous production of heat and cooling, and use of storage can make district cooling even more profitable. It is also possible to analyze the importance of flexible electricity and heating prices and see how they can be utilized, including the calculation of the probable prices on heating and cooling, and investments. The tool can make calculations on the following plant types: - Systems with only cooling without cold storage; - Systems with only cooling with cold storage; - Systems with cooling and heating controlled by cooling - with heat storage; - Systems with heating and cooling controlled by heating - with heating and cooling storage; - Systems with cooling and heating with optimized management - with heat storage. The tool can also be used to make general assessments, for example, to analyze the importance of flexible electricity and heating prices of typical district cooling systems, and for that matter, heat pump systems. (LN)

  2. Design of force-cooled conductors for large fusion magnets

    Energy Technology Data Exchange (ETDEWEB)

    Dresner, L.; Lue, J.W.

    1977-01-01

    Conductors cooled by supercritical helium in forced convection are under active consideration for large toroidal fusion magnets. One of the central problems in designing such force cooled conductors is to maintain an adequate stability margin while keeping the pumping power tolerably low. A method has been developed for minimizing the pumping power for fixed stability by optimally choosing the matrix-to-superconductor and the metal-to-helium ratios. Such optimized conductors reduce pumping power requirements for fusion size magnets to acceptable limits. Furthermore, the mass flow and hence pumping losses can be varied through a magnet according to the local magnetic field and magnitude of desired stability margin. Force cooled conductors give flexibility in operation, permitting, for example, higher fields to be obtained than originally intended by lowering the bath temperature or increasing the pumping power or both. This flexibility is only available if the pumping power is low to begin with. Scaling laws for the pumping requirement and stability margin as functions of operating current density, number of strands and such physical parameters as stabilizer resistivity and critical current density, have been proved. Numerical examples will be given for design of conductors intended for use in large toroidal fusion magnet systems.

  3. Central cooling: absorptive chillers

    Energy Technology Data Exchange (ETDEWEB)

    Christian, J.E.

    1977-08-01

    This technology evaluation covers commercially available single-effect, lithium-bromide absorption chillers ranging in nominal cooling capacities of 3 to 1,660 tons and double-effect lithium-bromide chillers from 385 to 1,060 tons. The nominal COP measured at operating conditions of 12 psig input steam for the single-effect machine, 85/sup 0/ entering condenser water, and 44/sup 0/F exiting chilled-water, ranges from 0.6 to 0.65. The nominal COP for the double-effect machine varies from 1.0 to 1.15 with 144 psig entering steam. Data are provided to estimate absorption-chiller performance at off-nominal operating conditions. The part-load performance curves along with cost estimating functions help the system design engineer select absorption equipment for a particular application based on life-cycle costs. Several suggestions are offered which may be useful for interfacing an absorption chiller with the remaining Integrated Community Energy System. The ammonia-water absorption chillers are not considered to be readily available technology for ICES application; therefore, performance and cost data on them are not included in this evaluation.

  4. Performance of Air-cooled Engine Cylinders Using Blower Cooling

    Science.gov (United States)

    Schey, Oscar W; Ellerbrock, Herman H , Jr

    1936-01-01

    An investigation was made to obtain information on the minimum quantity of air and power required to cool conventional air cooled cylinders at various operating conditions when using a blower. The results of these tests show that the minimum power required for satisfactory cooling with an overall blower efficiency of 100 percent varied from 2 to 6 percent of the engine power depending on the operating conditions. The shape of the jacket had a large effect on the cylinder temperatures. Increasing the air speed over the front of the cylinder by keeping the greater part of the circumference of the cylinder covered by the jacket reduced the temperatures over the entire cylinder.

  5. Moderate Cortical Cooling Eliminates Thalamocortical Silent States during Slow Oscillation.

    Science.gov (United States)

    Sheroziya, Maxim; Timofeev, Igor

    2015-09-23

    Reduction in temperature depolarizes neurons by a partial closure of potassium channels but decreases the vesicle release probability within synapses. Compared with cooling, neuromodulators produce qualitatively similar effects on intrinsic neuronal properties and synapses in the cortex. We used this similarity of neuronal action in ketamine-xylazine-anesthetized mice and non-anesthetized mice to manipulate the thalamocortical activity. We recorded cortical electroencephalogram/local field potential (LFP) activity and intracellular activities from the somatosensory thalamus in control conditions, during cortical cooling and on rewarming. In the deeply anesthetized mice, moderate cortical cooling was characterized by reversible disruption of the thalamocortical slow-wave pattern rhythmicity and the appearance of fast LFP spikes, with frequencies ranging from 6 to 9 Hz. These LFP spikes were correlated with the rhythmic IPSP activities recorded within the thalamic ventral posterior medial neurons and with depolarizing events in the posterior nucleus neurons. Similar cooling of the cortex during light anesthesia rapidly and reversibly eliminated thalamocortical silent states and evoked thalamocortical persistent activity; conversely, mild heating increased thalamocortical slow-wave rhythmicity. In the non-anesthetized head-restrained mice, cooling also prevented the generation of thalamocortical silent states. We conclude that moderate cortical cooling might be used to manipulate slow-wave network activity and induce neuromodulator-independent transition to activated states. Significance statement: In this study, we demonstrate that moderate local cortical cooling of lightly anesthetized or naturally sleeping mice disrupts thalamocortical slow oscillation and induces the activated local field potential pattern. Mild heating has the opposite effect; it increases the rhythmicity of thalamocortical slow oscillation. Our results demonstrate that slow oscillation can be

  6. Deep conversion of black oils with Eni Slurry technology

    Energy Technology Data Exchange (ETDEWEB)

    Panariti, Nicoletta; Rispoli, Giacomo

    2010-09-15

    Eni Slurry Technology represents a significant technological innovation in residue conversion and unconventional oils upgrading. EST allows the almost total conversion of heavy feedstocks into useful products, mainly transportation fuels, with a great major impact on the economic and environmental valorization of hydrocarbon resources. The peculiar characteristics of EST in terms of yields, products quality, absence of undesired by-products and feedstock flexibility constitute its superior economic and environmental attractiveness. The first full scale industrial plant based on this new technology will be realized in Eni's Sannazzaro refinery (23,000 bpd). Oil in is scheduled by 4th quarter 2012.

  7. On the conversion of neutron stars into quark stars

    CERN Document Server

    Pagliara, Giuseppe

    2013-01-01

    The possible existence of two families of compact stars, neutron stars and quark stars, naturally leads to a scenario in which a conversion process between the two stellar objects occurs with a consequent release of energy of the order of $10^{53}$ erg. We discuss recent hydrodynamical simulations of the burning process and neutrino diffusion simulations of cooling of a newly formed strange star. We also briefly discuss this scenario in connection with recent measurements of masses and radii of compact stars.

  8. Quality-assurance needs and goals in solar energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Gross, G. E.

    1980-07-01

    A discussion of the status of quality assurance activities in solar energy conversion technologies and of the needs for further efforts in this area is presented. The importance of reliability and quality assurance activities to various end users is briefly discussed. Some details of such activities in wind, active heating and cooling, and photovoltaic technologies are given. Suggestions for an inegrated reliability, quality assurance program are presented and their importance to the growth of solar energy application is discussed.

  9. Highly flexible, transparent and conducting CuS-nanosheet networks for flexible quantum-dot solar cells.

    Science.gov (United States)

    Xu, Zijie; Li, Teng; Zhang, Fayin; Hong, Xiaodan; Xie, Shuyao; Ye, Meidan; Guo, Wenxi; Liu, Xiangyang

    2017-03-17

    The rapid development of modern electronics has given rise to a higher demand for flexible and wearable energy sources. Flexible transparent conducting electrodes (TCEs) are one of the essential components of flexible/wearable thin-film solar cells (SCs). In this regard, we present highly transparent and conducting CuS-nanosheet (NS) networks with an optimized sheet resistance (Rs) as low as 50 Ω sq(-1) at 85% transmittance as a counter electrode (CE) for flexible quantum-dot solar cells (QDSCs). The CuS NS network electrode exhibits remarkable mechanical flexibility under bending tests compared to traditional ITO/plastic substrates and sputtered CuS films. Herein, CuS NS networks not only served as conducting films for collecting electrons from the external circuit, but also served as superior catalysts for reducing polysulfide (S(2-)/Sx(2-)) electrolytes. A power conversion efficiency (PCE) up to 3.25% was achieved for the QDSCs employing CuS NS networks as CEs, which was much higher than those of the devices based on Pt networks and sputtered CuS films. We believe that such CuS network TCEs with high flexibility, transparency, conductivity and catalytic activity could be widely used in making wearable electronic products.

  10. The Flexibility Hypothesis of Healing.

    Science.gov (United States)

    Hinton, Devon E; Kirmayer, Laurence J

    2017-03-01

    Theories of healing have attempted to identify general mechanisms that may work across different modalities. These include altering expectations, remoralization, and instilling hope. In this paper, we argue that many forms of healing and psychotherapy may work by inducing positive psychological states marked by flexibility or an enhanced ability to shift cognitive sets. Healing practices may induce these states of cognitive and emotional flexibility through specific symbolic interventions we term "flexibility primers" that can include images, metaphors, music, and other media. The flexibility hypothesis suggests that cognitive and emotional flexibility is represented, elicited, and enacted through multiple modalities in healing rituals. Identifying psychological processes and cultural forms that evoke and support cognitive and emotional flexibility provides a way to understand the cultural specificity and potential efficacy of particular healing practices and can guide the design of interventions that promote resilience and well-being.

  11. Freely flowing conversations

    DEFF Research Database (Denmark)

    Aakjær, Marie Kirstejn; Andrade, David; Dexters, Peter

    2012-01-01

    and relationships may allow us to transcend the barriers of our formal positions. To us it is a testimony of the struggles and the good times we have shared while attempting to improve life in prisons. Also, this is an occasion for reflection on what we have learned from the process. The User Driven Innovation (in...... for guards. It has turned the focus of the organization towards the importance of relationship-building. In 2011 the Director General and the Prison Governors stated that building positive relations is the most important future task for Danish prisons both in regards to improving prison environments...... relations by changing conversations. Through the theoretical framework of the complexity approach, we discuss how this may lead to organizational change. Finally we suggest that inviting inmates to take part in conversations about core organizational development may be a fundamental strategy in trying...

  12. Conversion electron surface imaging

    CERN Document Server

    Irwin, G M; Wehner, A

    1999-01-01

    A method of imaging the Moessbauer absorption over the surface of a sample based on counting conversion electrons emitted from the surface following resonant absorption of gamma radiation is described. This Conversion Electron Surface Imaging (CESI) method is somewhat analogous to Magnetic Resonance Imaging (MRI), particularly chemical shift imaging, and similar tomographic reconstruction techniques are involved in extracting the image. The theory behind the technique and a prototype device is described, as well as the results of proof-of-principle experiments which demonstrate the function of the device. Eventually this same prototype device will be part of a system to determine the spatial variation of the Moessbauer spectrum over the surface of a sample. Applications include imaging of variations of surface properties of steels and other iron containing alloys, as well as other surfaces over which sup 5 sup 7 Fe has been deposited.

  13. Les conversions de cens

    Directory of Open Access Journals (Sweden)

    Laurent Feller

    2006-09-01

    Full Text Available Dans le cadre d’une recherche entamée sur la circulation des richesses au Moyen Âge, la réflexion s’est dirigée vers la question de la conversion, c’est-à-dire du passage d’une forme à une autre dans la mesure des valeurs (argent contre nature, objets dont l’usage se transforme en s’échangeant, conversions monétaires. Un cycle de trois rencontres est prévu afin de débrouiller une question complexe qui devrait permettre au groupe d’éclairer la question de la valeur des choses au Moyen Âge. La...

  14. Clinical linguistics: conversational reflections.

    Science.gov (United States)

    Crystal, David

    2013-04-01

    This is a report of the main points I made in an informal "conversation" with Paul Fletcher and the audience at the 14th ICPLA conference in Cork. The observations arose randomly, as part of an unstructured 1-h Q&A, so they do not provide a systematic account of the subject, but simply reflect the issues which were raised by the conference participants during that time.

  15. Conversations with Miss Jane

    Directory of Open Access Journals (Sweden)

    Geneviève Fabre

    2006-05-01

    Full Text Available Considering the wide range of conversations in the autobiography, this essay will attempt to appraise the importance of these verbal exchanges in relation to the overall narrative structure of the book and to the prevalent oral tradition in Louisiana culture, as both an individual and communal expression. The variety of circumstances, the setting and staging, the interlocutors , and the complex intersection of time and place, of stories and History, will be examined; in these conversations with Miss Jane many actors participate, from  the interviewer-narrator, to most characters; even the reader becomes involved.Speaking, hearing, listening, keeping silent is an elaborate ritual that performs many functions; besides conveying news or rumors, it imparts information on the times and on the life of a “representative” woman whose existence - spanning a whole century- is both singular and emblematic. Most importantly this essay will analyse the resonance of an eventful and often dramatic era on her sensibility and conversely show how her evolving sensibility informs that history and draws attention to aspects that might have passed unnoticed or be forever silenced. Jane’s desire for liberty and justice is often challenged as she faces the possibilities of life or death.Conversations build up a complex, often contradictory, but compelling portrait: torn between silence and vehemence, between memories and the urge to meet the future, Jane summons body and mind to find her way through the maze of a fast changing world; self-willed and obstinate she claims her right to speak, to express with wit and wisdom her firm belief in the word, in the ability to express deep seated convictions and faith and a whole array of feelings and emotions.

  16. Cooling arrangement for a tapered turbine blade

    Science.gov (United States)

    Liang, George

    2010-07-27

    A cooling arrangement (11) for a highly tapered gas turbine blade (10). The cooling arrangement (11) includes a pair of parallel triple-pass serpentine cooling circuits (80,82) formed in an inner radial portion (50) of the blade, and a respective pair of single radial channel cooling circuits (84,86) formed in an outer radial portion (52) of the blade (10), with each single radial channel receiving the cooling fluid discharged from a respective one of the triple-pass serpentine cooling circuit. The cooling arrangement advantageously provides a higher degree of cooling to the most highly stressed radially inner portion of the blade, while providing a lower degree of cooling to the less highly stressed radially outer portion of the blade. The cooling arrangement can be implemented with known casting techniques, thereby facilitating its use on highly tapered, highly twisted Row 4 industrial gas turbine blades that could not be cooled with prior art cooling arrangements.

  17. Flexible cultural repertoires

    DEFF Research Database (Denmark)

    Lindegaard, Marie Rosenkrantz

    2016-01-01

    Despite extensive studies of street culture and the risks of offending and victimization in urban marginalized areas, little is known about the role of cultural repertoires for variation in victimization risks among young men not involved in crime. Based on two ethnographic studies, conducted...... varying cultural repertoires, in particularly heterogeneous flexible repertoires, influence offending and victimization patterns among young men in high-risk settings....... independently of the authors in neighbouring township areas of Cape Town, we offer insights into patterns of victimization among young men not involved in crime who live and attend school in the townships. Young men who perform decent cultural repertoires are highly exposed to victimization due to their moral...

  18. Conformational flexibility of aspartame.

    Science.gov (United States)

    Toniolo, Claudio; Temussi, Pierandrea

    2016-05-01

    L-Aspartyl-L-phenylalanine methyl ester, better known as aspartame, is not only one of the most used artificial sweeteners, but also a very interesting molecule with respect to the correlation between molecular structure and taste. The extreme conformational flexibility of this dipeptide posed a huge difficulty when researchers tried to use it as a lead compound to design new sweeteners. In particular, it was difficult to take advantage of its molecular model as a mold to infer the shape of the, then unknown, active site of the sweet taste receptor. Here, we follow the story of the 3D structural aspects of aspartame from early conformational studies to recent docking into homology models of the receptor. © 2016 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 376-384, 2016.

  19. New Approaches to Final Cooling

    CERN Document Server

    Neuffer, David

    2015-01-01

    A high-energy muon collider scenario requires a "final cooling" system that reduces transverse emittance by a factor of ~10 while allowing longitudinal emittance increase. The baseline approach has low-energy transverse cooling within high-field solenoids, with strong longitudinal heating. This approach and its recent simulation are discussed. Alternative approaches which more explicitly include emittance exchange are also presented. Round-to-flat beam transform, transverse slicing, and longitudinal bunch coalescence are possible components of the alternative approach. A more explicit understanding of solenoidal cooling beam dynamics is introduced.

  20. Cooling towers principles and practice

    CERN Document Server

    Hill, G B; Osborn, Peter D

    1990-01-01

    Cooling Towers: Principles and Practice, Third Edition, aims to provide the reader with a better understanding of the theory and practice, so that installations are correctly designed and operated. As with all branches of engineering, new technology calls for a level of technical knowledge which becomes progressively higher; this new edition seeks to ensure that the principles and practice of cooling towers are set against a background of up-to-date technology. The book is organized into three sections. Section A on cooling tower practice covers topics such as the design and operation of c

  1. CLIC inner detectors cooling simulations

    CERN Document Server

    Duarte Ramos, F.; Villarejo Bermudez, M.

    2014-01-01

    The strict requirements in terms of material budget for the inner region of the CLIC detector concepts require the use of a dry gas for the cooling of the respective sen- sors. This, in conjunction with the compactness of the inner volumes, poses several challenges for the design of a cooling system that is able to fulfil the required detec- tor specifications. This note introduces a detector cooling strategy using dry air as a coolant and shows the results of computational fluid dynamics simulations used to validate the proposed strategy.

  2. Natural gas conversion process

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    The experimental apparatus was dismantled and transferred to a laboratory space provided by Lawrence Berkeley Laboratory (LBL) which is already equipped with a high-ventilation fume hood. This will enable us to make tests at higher gas flow rates in a safe environment. Three papers presented at the ACS meeting in San Francisco (Symposium on Natural Gas Upgrading II) April 5--10, 1992 show that the goal of direct catalytic conversion of Methane into heavier Hydrocarbons in a reducing atmosphere is actively pursued in three other different laboratories. There are similarities in their general concept with our own approach, but the temperature range of the experiments reported in these recent papers is much lower and this leads to uneconomic conversion rates. This illustrates the advantages of Methane activation by a Hydrogen plasma to reach commercial conversion rates. A preliminary process flow diagram was established for the Integrated Process, which was outlined in the previous Quarterly Report. The flow diagram also includes all the required auxiliary facilities for product separation and recycle of the unconverted feed as well as for the preparation and compression of the Syngas by-product.

  3. Discoal: flexible coalescent simulations with selection.

    Science.gov (United States)

    Kern, Andrew D; Schrider, Daniel R

    2016-12-15

    Here we describe discoal, a coalescent simulator able to generate population samples that include selective sweeps in a feature-rich, flexible manner. discoal can perform simulations conditioning on the fixation of an allele due to drift or either hard or soft sweeps-even those occurring a large genetic distance away from the simulated locus. discoal can simulate sweeps with recurrent mutation to the adaptive allele, recombination, and gene conversion, under non-equilibrium demographic histories and without specifying an allele frequency trajectory in advance. discoal is implemented in the C programming language. Source code is freely available on GitHub (https://github.com/kern-lab/discoal) under a GNU General Public License. kern@dls.rutgers.edu or dan.schrider@rutgers.eduSupplementary information: Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. Photonic hybrid assembly through flexible waveguides

    Science.gov (United States)

    Wörhoff, K.; Prak, A.; Postma, F.; Leinse, A.; Wu, K.; Peters, T. J.; Tichem, M.; Amaning-Appiah, B.; Renukappa, V.; Vollrath, G.; Balcells-Ventura, J.; Uhlig, P.; Seyfried, M.; Rose, D.; Santos, R.; Leijtens, X. J. M.; Flintham, B.; Wale, M.; Robbins, D.

    2016-05-01

    Fully automated, high precision, cost-effective assembly technology for photonic packages remains one of the main challenges in photonic component manufacturing. Next to the cost aspect the most demanding assembly task for multiport photonic integrated circuits (PICs) is the high-precision (±0.1 μm) alignment and fixing required for optical I/O in InP PICs, even with waveguide spot size conversion. In a European research initiative - PHASTFlex - we develop and investigate an innovative, novel assembly concept, in which the waveguides in a matching TriPleX interposer PIC are released during fabrication to make them movable. After assembly of both chips by flip-chip bonding on a common carrier, TriPleX based actuators and clamping functions position and fix the flexible waveguides with the required accuracy.

  5. Highly flexible InSnO electrodes on thin colourless polyimide substrate for high-performance flexible CH3NH3PbI3 perovskite solar cells

    Science.gov (United States)

    Park, Jeong-Il; Heo, Jin Hyuck; Park, Sung-Hyun; Hong, Ki Il; Jeong, Hak Gee; Im, Sang Hyuk; Kim, Han-Ki

    2017-02-01

    We fabricated high-performance flexible CH3NH3PbI3 (MAPbI3) perovskite solar cells with a power conversion efficiency of 15.5% on roll-to-roll sputtered ITO films on 60 μm-thick colourless polyimide (CPI) substrate. Due to the thermal stability of the CPI substrate, an ITO/CPI sample subjected to rapid thermal annealing at 300 °C showed a low sheet resistance of 57.8 Ω/square and high transmittance of 83.6%, which are better values than those of an ITO/PET sample. Outer and inner bending tests demonstrated that the mechanical flexibility of the ITO/CPI was superior to that of the conventional ITO/PET sample owing to the thinness of the CPI substrate. In addition, due to its good mechanical flexibility, the ITO/CPI showed no change in resistance after 10,000 cycle outer and inner dynamic fatigue tests. Flexible perovskite solar cells with the structure of Au/PTAA/MAPbI3/ZnO/ITO/CPI showed a high power conversion efficiency of 15.5%. The successful operation of these flexible perovskite solar cells on ITO/CPI substrate indicated that the ITO film on thermally stable CPI substrate is a promising of flexible substrate for high-temperature processing, a finding likely to advance the commercialization of cost-efficient flexible perovskite solar cells.

  6. Passive low energy cooling of buildings

    CERN Document Server

    Givoni, Baruch

    1994-01-01

    A practical sourcebook for building designers, providing comprehensive discussion of the impact of basic architectural choices on cooling efficiency, including the layout and orientation of the structure, window size and shading, exterior color, and even the use of plantings around the site. All major varieties of passive cooling systems are presented, with extensive analysis of performance in different types of buildings and in different climates: ventilation; radiant cooling; evaporative cooling; soil cooling; and cooling of outdoor spaces.

  7. Nuclear Air-Brayton Combined Cycle Power Conversion Design, Physical Performance Estimation and Economic Assessment

    Science.gov (United States)

    Andreades, Charalampos

    The combination of an increased demand for electricity for economic development in parallel with the widespread push for adoption of renewable energy sources and the trend toward liberalized markets has placed a tremendous amount of stress on generators, system operators, and consumers. Non-guaranteed cost recovery, intermittent capacity, and highly volatile market prices are all part of new electricity grids. In order to try and remediate some of these effects, this dissertation proposes and studies the design and performance, both physical and economic, of a novel power conversion system, the Nuclear Air-Brayton Combined Cycle (NACC). The NACC is a power conversion system that takes a conventional industrial frame type gas turbine, modifies it to accept external nuclear heat at 670°C, while also maintaining its ability to co-fire with natural gas to increase temperature and power output at a very quick ramp rate. The NACC addresses the above issues by allowing the generator to gain extra revenue through the provision of ancillary services in addition to energy payments, the grid operator to have a highly flexible source of capacity to back up intermittent renewable energy sources, and the consumer to possibly see less volatile electricity prices and a reduced probability of black/brown outs. This dissertation is split into six sections that delve into specific design and economic issues related to the NACC. The first section describes the basic design and modifications necessary to create a functional externally heated gas turbine, sets a baseline design based upon the GE 7FB, and estimates its physical performance under nominal conditions. The second section explores the off-nominal performance of the NACC and characterizes its startup and shutdown sequences, along with some of its safety measures. The third section deals with the power ramp rate estimation of the NACC, a key performance parameter in a renewable-heavy grid that needs flexible capacity. The

  8. Rotor scale model tests for power conversion unit of GT-MHR

    Energy Technology Data Exchange (ETDEWEB)

    Baxi, C.B., E-mail: baxicb1130@hotmail.com [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States); Telengator, A.; Razvi, J. [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States)

    2012-10-15

    The gas turbine modular helium reactor (GT-MHR) combines a modular high-temperature gas-cooled reactor (HTGR) nuclear heat source with a closed Brayton gas-turbine cycle power conversion unit (PCU) for thermal to electric energy conversion. The PCU has a vertical orientation and is supported on electromagnetic bearings (EMB). The rotor scale model (RSM) tests are intended to directly model the control of EMB and rotor dynamic characteristics of the full-scale GT-MHR turbo-machine (TM). The objectives of the RSM tests are to: Bullet Confirm the EMB control system design for the GT-MHR turbo machine over the full-range of operation. Bullet Confirm the redundancy and on-line maintainability features that have been specified for the EMBs. Bullet Provide a benchmark for validation of analytical tools that will be used for independent analyses of the EMB subsystem design. Bullet Provide experience with the installation, operation and maintenance of EMBs supporting multiple rotors with flexible couplings. As with the full-scale TM, the RSM incorporates two rotors that are joined by a flexible coupling. Each of the rotors is supported on one axial and two radial EMBs. Additional devices, similar in concept to radial EMBs, are installed to simulate magnetic and/or mechanical forces representing those that would be seen by the exciter, generator, compressors and turbine. Overall, the lengths of the RSM rotor is about 1/3rd that of the full-scale TM, while the diameters are approximately 1/5th scale. The design and sizing of the rotor is such that the number and values of critical speeds in the RSM are the same as in the full-scale TM. The EMBs are designed such that their response to rotor dynamic forces is representative of the full-scale TM. The fabrication and assembly of the RSM was completed at the end of 2008. All start up adjustments were finished in December 2009. To-date the generator rotor has been supported in the EMBs and rotated up to 1800 rpm. Final tests are

  9. Compressor bleed cooling fluid feed system

    Science.gov (United States)

    Donahoo, Eric E; Ross, Christopher W

    2014-11-25

    A compressor bleed cooling fluid feed system for a turbine engine for directing cooling fluids from a compressor to a turbine airfoil cooling system to supply cooling fluids to one or more airfoils of a rotor assembly is disclosed. The compressor bleed cooling fluid feed system may enable cooling fluids to be exhausted from a compressor exhaust plenum through a downstream compressor bleed collection chamber and into the turbine airfoil cooling system. As such, the suction created in the compressor exhaust plenum mitigates boundary layer growth along the inner surface while providing flow of cooling fluids to the turbine airfoils.

  10. Ocean energy conversion - A reality

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.

    This chapter presents an overview of ocean energy conversion in respect of its significance as the renewable energy resources. It deals with the thermodynamic principles relating to ocean thermal energy conversion (OTEC). Besides, it provides an in...

  11. Cooling Technology for Electronic Computers

    Science.gov (United States)

    Nakayama, Wataru

    The rapid growth of data processing speed in computers has been sustained by the advances in cooling technology. This article first presents a review of the published data of heat loads in recent Japanese large-scale computers. The survey indicates that, since around 1980, the high-level integration of microelectronic circuits has brought about almost four fold increase in the power dissipation from logic chips. The integration also has invited the evolutions of multichip modules and new schemes of electronic interconnections. Forced convection air-cooling and liquid cooling coupled with thermal connectors are discussed with reference to the designs employed in actual computers. More advanced cooling schemes are also discussed. Finally, the importance of thermal environmental control of computer rooms is emphasized.

  12. Cooled Ceramic Turbine Vane Project

    Data.gov (United States)

    National Aeronautics and Space Administration — N&R Engineering will investigate the feasibility of cooled ceramics, such as ceramic matrix composite (CMC) turbine blade concepts that can decrease specific...

  13. Surface-induced evaporative cooling

    Institute of Scientific and Technical Information of China (English)

    Ke Min; Yan Bo; Cheng Feng; Wang Yu-Zhu

    2009-01-01

    The effects of surface-induced evaporative cooling on an atom chip are investigated. The evolutions of temperature, number and phase-space density of the atom cloud are measured when the atom cloud is brought close to the surface. Rapid decrease of the temperature and number of the atoms is found when the atom-surface distance is < 100 μm. A gain of about a factor of five on the phase-space density is obtained. It is found that the efficiency of the surface-induced evaporative cooling depends on the atom-surface distance and the shape of the evaporative trap. When the atoms are moved very close to the surface, severe heating is observed, which dominates when the holding time is > 8 ms. It is important that the surface-induced evaporative cooling offers novel possibilities for the realization of a continuous condensation, where a spatially varying evaporative cooling is required.

  14. Flexible and fragmentable tandem photosensitive nanocrystal skins

    Science.gov (United States)

    Akhavan, S.; Uran, C.; Bozok, B.; Gungor, K.; Kelestemur, Y.; Lesnyak, V.; Gaponik, N.; Eychmüller, A.; Demir, H. V.

    2016-02-01

    We proposed and demonstrated the first account of large-area, semi-transparent, tandem photosensitive nanocrystal skins (PNSs) constructed on flexible substrates operating on the principle of photogenerated potential buildup, which avoid the need for applying an external bias and circumvent the current-matching limitation between junctions. We successfully fabricated and operated the tandem PNSs composed of single monolayers of colloidal water-soluble CdTe and CdHgTe nanocrystals (NCs) in adjacent junctions on a Kapton polymer tape. Owing to the usage of a single NC layer in each junction, noise generation was significantly reduced while keeping the resulting PNS films considerably transparent. In each junction, photogenerated excitons are dissociated at the interface of the semi-transparent Al electrode and the NC layer, with holes migrating to the contact electrode and electrons trapped in the NCs. As a result, the tandem PNSs lead to an open-circuit photovoltage buildup equal to the sum of those of the two single junctions, exhibiting a total voltage buildup of 128.4 mV at an excitation intensity of 75.8 μW cm-2 at 350 nm. Furthermore, we showed that these flexible PNSs could be bent over 3.5 mm radius of curvature and cut out in arbitrary shapes without damaging the operation of individual parts and without introducing any significant loss in the total sensitivity. These findings indicate that the NC skins are promising as building blocks to make low-cost, flexible, large-area UV/visible sensing platforms with highly efficient full-spectrum conversion.We proposed and demonstrated the first account of large-area, semi-transparent, tandem photosensitive nanocrystal skins (PNSs) constructed on flexible substrates operating on the principle of photogenerated potential buildup, which avoid the need for applying an external bias and circumvent the current-matching limitation between junctions. We successfully fabricated and operated the tandem PNSs composed of

  15. Measured performance of a 3 ton LiBr absorption water chiller and its effect on cooling system operation

    Science.gov (United States)

    Namkoong, D.

    1976-01-01

    A three ton lithium bromide absorption water chiller was tested for a number of conditions involving hot water input, chilled water, and the cooling water. The primary influences on chiller capacity were the hot water inlet temperature and the cooling water inlet temperature. One combination of these two parameters extended the output to as much as 125% of design capacity, but no combination could lower the capacity to below 60% of design. A cooling system was conceptually designed so that it could provide several modes of operation. Such flexibility is needed for any solar cooling system to be able to accommodate the varying solar energy collection and the varying building demand. It was concluded that a three-ton absorption water chiller with the kind of performance that was measured can be incorporated into a cooling system such as that proposed, to provide efficient cooling over the specified ranges of operating conditions.

  16. Measured performance of a 3-ton LiBr absorption water chiller and its effect on cooling system operation

    Science.gov (United States)

    Namkoong, D.

    1976-01-01

    A 3-ton lithium bromide absorption water chiller was tested for a number of conditions involving hot-water input, chilled water, and the cooling water. The primary influences on chiller capacity were the hot water inlet temperature and the cooling water inlet temperature. One combination of these two parameters extended the output to as much as 125% of design capacity, but no combination could lower the capacity to below 60% of design. A cooling system was conceptually designed so that it could provide several modes of operation. Such flexibility is needed for any solar cooling system to be able to accommodate the varying solar energy collection and the varying building demand. It is concluded that a 3-ton absorption water chiller with the kind of performance that was measured can be incorporated into a cooling system such as that proposed, to provide efficient cooling over the specified ranges of operating conditions.

  17. Turbine Blade Cooling System Optimization

    OpenAIRE

    GIRARDEAU, Julian; PAILHES, Jérôme; SEBASTIAN, Patrick; PARDO, Frédéric; Nadeau, Jean-Pierre

    2013-01-01

    The authors wish to thank turbine designers from TURBOMECA SAFRAN Group.; International audience; Designing high performance cooling systems suitable for preserving the service lifetime of nozzle guide vanes of turboshaft engines leads to significant aerodynamic losses. These losses jeopardize the performance of the whole engine. In the same time, a low efficiency cooling system may affect the costs of maintenance repair and overhaul of the engine as component life decreases. Consequently, de...

  18. DETERMINATION OF RADIATOR COOLING SURFACE

    Directory of Open Access Journals (Sweden)

    A. I. Yakubovich

    2009-01-01

    Full Text Available The paper proposes a methodology for calculation of a radiator cooling surface with due account of heat transfer non-uniformity on depth of its core. Calculation of radiator cooling surfaces of «Belarus-1221» and «Belarus-3022» tractors has been carried out in the paper. The paper also advances standard size series of radiators for powerful «Belarus» tractor type.

  19. Quantum limit of photothermal cooling

    CERN Document Server

    De Liberato, Simone; Nori, Franco

    2010-01-01

    We study the problem of cooling a mechanical oscillator using the photothermal (bolometric) force. Contrary to previous attempts to model this system, we take into account the noise effects due to the granular nature of photon absorption. This allows us to tackle the cooling problem down to the noise dominated regime and to find reasonable estimates for the lowest achievable phonon occupation in the cantilever.

  20. Cooling Shelf For Electronic Equipment

    Science.gov (United States)

    Tanzer, Herbert J.

    1989-01-01

    Heat-pipe action cools and maintains electronics at nearly constant temperature. System designed to control temperatures of spacecraft shelves or baseplates by combining honeycomb sandwich panel with reservoir of noncondensable gas and processing resulting device as variable-conductance heat pipe. Device provides flat surface for mounting heat-dissipating electronics that is effectively cooled and maintained at nearly constant temperature. Potentially useful in freeze drying, refrigeration, and air conditioning.

  1. Principles of solid-state power conversion

    Science.gov (United States)

    Tarter, R. E.

    1985-12-01

    The purpose of this book is to assemble, in one place, the comprehensive tools necessary to meet the growing demands placed upon solid-state power conversion equipment. Aspects of transient analysis, circuit analysis, and waveforms are discussed, taking into account waveform relations, magnetic fields, dielectric fields, the RL circuit, the RC circuit, the RLC circuit, the RLCR circuit with a DC input, AC circuit analysis, and components scaling. Semiconductors and resistors are considered along with capacitors, transformers, inductors, conductors, rectifiers and filters, phase-control circuits, transistor inverters, thyristor inverters, switching regulators, DC-DC converters, protection and safety, electromagnetic compatibility and grounding, semiconductor and equipment cooling, reliability and quality, regulated power supplies, and uninterruptible power systems. Attention is given to magnetic materials, toroid tape core transformers, permalloy powder cores, a six-phase dual bridge, thermal conduction and resistance, heat pipes, and thermoelectric coolers.

  2. Microbial Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, Merry [American Society for Microbiology (ASM), Washington, DC (United States); Wall, Judy D. [Univ. of Missouri, Columbia, MO (United States)

    2006-10-01

    The American Academy of Microbiology convened a colloquium March 10-12, 2006, in San Francisco, California, to discuss the production of energy fuels by microbial conversions. The status of research into various microbial energy technologies, the advantages and disadvantages of each of these approaches, research needs in the field, and education and training issues were examined, with the goal of identifying routes for producing biofuels that would both decrease the need for fossil fuels and reduce greenhouse gas emissions. Currently, the choices for providing energy are limited. Policy makers and the research community must begin to pursue a broader array of potential energy technologies. A diverse energy portfolio that includes an assortment of microbial energy choices will allow communities and consumers to select the best energy solution for their own particular needs. Funding agencies and governments alike need to prepare for future energy needs by investing both in the microbial energy technologies that work today and in the untested technologies that will serve the world’s needs tomorrow. More mature bioprocesses, such as ethanol production from starchy materials and methane from waste digestors, will find applications in the short term. However, innovative techniques for liquid fuel or biohydrogen production are among the longer term possibilities that should also be vigorously explored, starting now. Microorganisms can help meet human energy needs in any of a number of ways. In their most obvious role in energy conversion, microorganisms can generate fuels, including ethanol, hydrogen, methane, lipids, and butanol, which can be burned to produce energy. Alternatively, bacteria can be put to use in microbial fuel cells, where they carry out the direct conversion of biomass into electricity. Microorganisms may also be used some day to make oil and natural gas technologies more efficient by sequestering carbon or by assisting in the recovery of oil and

  3. Energy conversion via ferroic materials: Materials, mechanisms, and applications

    Science.gov (United States)

    Chin, Huai-An

    Energy conversion is a process converting one form of energy into another. Significant research effort has been dedicated to energy conversion mechanisms for portable energy conversion. Specifically, mechanisms based on ferroic materials have been widely explored for this goal. Ferroic materials include ferromagnetic, ferroelectric and ferroelastic materials. This thesis is focused on two ferroic materials: ferromagnetic TbxDy1-xFe2 (x ˜ 0.3, Terfenol-D), and ferroelectric barium strontium titanate (BST) including its paraelectric phase, for their energy conversion mechanisms. We grew and characterized these materials, followed by device fabrication to study potential energy conversion mechanisms in resulting devices. With Terfenol-D, we demonstrated a wireless energy-conversion process via the Villari effect, i.e. magnetic flux change induced by mechanical input. A new technique of transfer-printing a Terfenol-D film onto a flexible substrate was developed to study this mechanism. The transferred Terfenol-D showed a high saturation magnetization (˜ 1.3 T) and flexibility (strain ˜ 1.9 %). Subsequently, the Villari effect was successfully utilized to convert mechanical energy, from a mechanical source and a simulated biomechanical source, into electricity. For next projects, another ferroic material, a high-permittivity (dielectric constant ˜ 200) BST was sputtered on Pt/SiO2/Si or stainless steels to form a metal-insulator(BST)-metal heterostructure. The BST was found to be paraelectric when grown upon Pt/SiO2/Si, whereas it was ferroelectric when grown on the stainless steel. Two different mechanisms were therefore studied on these two modifications. In the paraelectric BST we found a new thermal-electric response via a flexoelectricity-mediated mechanism, which was enabled by a large strain gradient (> 104/m) produced by lattice mismatch. With the enhanced flexoelectricity from the large strain gradient, electrical output was generated under thermal cycling

  4. Experimental realization of two-isotope collision-assisted Zeeman cooling

    Science.gov (United States)

    Hamilton, Mathew

    The work presented in this thesis focuses on the demonstration and initial evaluation of a novel non-evaporative cooling method called collision-assisted Zeeman cooling. For this realization, an ultracold gas consisting of a mixture of 87Rb and 85Rb was used. Cooling was accomplished through interisotope inelastic spin-exchange collisions that converted kinetic energy into magnetic energy. Continual optical pumping spin polarized the 85Rb which ensured that only kinetic energy reducing collisions occurred and the scattered pump photons carried entropy out of the system. Thus, cooling of the ultracold gas can be achieved without requiring the loss of any atoms in order to do so. This represents a theoretical advantage over forced evaporative cooling, which is the current state-of-the-art cooling technique in most experiments. This thesis discusses the details of collision-assisted Zeeman cooling, as well as how the theory of the technique has been extended from cooling a single species to cooling with two species. There are many predicted advantages from using two rather than one species of atom in this type of cooling: greater flexibility in finding favorable spin-exchange collision rates, easier requirements on the magnetic fields that must be used, and an additional means to mitigate reabsorption (the primary limitation in many if not most non-evaporative cooling techniques). The experimental considerations needed to prepare a system that simultaneously trapped two isotopes to be able to perform collision-assisted Zeeman cooling are discussed. Because this cooling scheme is highly reliant on the initial conditions of the system, a focused experiment examining the loading of the optical trap with both isotopes of Rb was conducted and the results of that experiment are described here. The first experimental observations of spin-exchange collisions in an ultracold gas mixture of Rb are described as a part of this work. The experiments where collision-assisted Zeeman

  5. Energy Efficient Electronics Cooling Project

    Energy Technology Data Exchange (ETDEWEB)

    Steve O' Shaughnessey; Tim Louvar; Mike Trumbower; Jessica Hunnicutt; Neil Myers

    2012-02-17

    Parker Precision Cooling Business Unit was awarded a Department of Energy grant (DE-EE0000412) to support the DOE-ITP goal of reducing industrial energy intensity and GHG emissions. The project proposed by Precision Cooling was to accelerate the development of a cooling technology for high heat generating electronics components. These components are specifically related to power electronics found in power drives focused on the inverter, converter and transformer modules. The proposed cooling system was expected to simultaneously remove heat from all three of the major modules listed above, while remaining dielectric under all operating conditions. Development of the cooling system to meet specific customer's requirements and constraints not only required a robust system design, but also new components to support long system functionality. Components requiring further development and testing during this project included pumps, fluid couplings, cold plates and condensers. All four of these major categories of components are required in every Precision Cooling system. Not only was design a key area of focus, but the process for manufacturing these components had to be determined and proven through the system development.

  6. Conversion of methane through dielectric-barrier discharge plasma

    Institute of Scientific and Technical Information of China (English)

    Baowei WANG; Xiaolei CAO; Kuanhui YANG; Genhui XU

    2008-01-01

    Methane coupling to produce C2 hydrocar-bons through a dielectric-barrier discharge (DBD) plasma reaction was studied in four DBD reactors. The effects of high voltage electrode position, different discharge gap, types of inner electrode, volume ratio of hydrogen to methane and air cooling method on the conversion of methane and distribution of products were investigated. Conversion of methane is obviously lower when a high voltage electrode acts as an outer electrode than when it acts as an inner electrode. The lifting of reaction temper-ature becomes slow due to cooling of outer electrode and the temperature can be controlled in the expected range of 60℃-150℃ for ensuring better methane conversion and safe operation. The parameters of reactors have obvious effects on methane conversion, but it only slightly affects distribution of the products. The main products are ethyl-ene, ethane and propane. The selectivity of C2 hydrocar-bons can reach 74.50% when volume ratio of hydrogen to methane is 1.50.

  7. Infrared up-conversion microscope

    DEFF Research Database (Denmark)

    2014-01-01

    There is presented an up-conversion infrared microscope (110) arranged for imaging an associated object (130), wherein the up-conversion infrared microscope (110) comprises a non-linear crystal (120) arranged for up-conversion of infrared electromagnetic radiation, and wherein an objective optical...

  8. Infrared up-conversion telescope

    DEFF Research Database (Denmark)

    2014-01-01

    There is presented to an up-conversion infrared telescope (110) arranged for imaging an associated scene (130), wherein the up-conversion infrared telescope (110) comprises a non-linear crystal (120) arranged for up-conversion of infrared electromagnetic radiation, and wherein a first optical...

  9. Special Features in Children's Conversations.

    Science.gov (United States)

    Karjalainen, Merja

    In a study of features that seem to be typical of children's conversations, 10 Finnish preschool children's conversations were videotaped and audiotaped over a period of 10 hours. The children were taped in conversation, play, fairy tale, and eating situations. Among the findings are that all children enjoy playing with language, but some initiate…

  10. Building Highly Flexible Polyelectrolyte Nanotubes

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ Flexibility of polyelectrolyte nanotubes is necessary if they are to be exploited in applications such as developing photoelectric devices with strong mechanical properties. In a recent attempt, high flexibility has been observed from such nanotubes prepared by a research team headed by Prof. Li Junbai of the CAS Institute of Chemistry (ICCAS).

  11. On flexible and rigid nouns

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    2008-01-01

    , Non-Verb, Modifier), there are also flexible word classes within the rigid lexical category Noun (Set Noun, Sort Noun, General Noun). Members of flexible word classes are characterized by their vague semantics, which in the case of nouns means that values for the semantic features Shape...

  12. On flexible and rigid nouns

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    2010-01-01

    This article argues that in addition to the major flexible lexical categories in Hengeveld’s classification of parts of speech systems (Contentive, Non-Verb, Modifier), there are also flexible word classes within the rigid lexical category Noun (Set Noun, Sort Noun, General Noun). Members...

  13. Function Machines & Flexible Algebraic Thought.

    Science.gov (United States)

    Davis, Gary E.; McGowen, Mercedes A.

    This paper explores how college students understand ideas of functions, and which representations are productive for them in promoting their ability to work flexibly across representations. The study used pre- and post-test scores, and triangulations via student self evaluations, to generate a hypothesis related to flexible thinking and success in…

  14. Sensor Technologies on Flexible Substrates

    Science.gov (United States)

    Koehne, Jessica

    2016-01-01

    NASA Ames has developed sensor technologies on flexible substrates integrated into textiles for personalized environment monitoring and human performance evaluation. Current technologies include chemical sensing for gas leak and event monitoring and biological sensors for human health and performance monitoring. Targeted integration include next generation EVA suits and flexible habitats.

  15. Retirement Flexibility and Portfolio Choice

    NARCIS (Netherlands)

    Adema, Y.; Bonenkamp, J.; Meijdam, A.C.

    2011-01-01

    This paper explores the interaction between retirement flexibility and portfolio choice in an overlapping-generations model. We analyse this interaction both in a partial-equilibrium and general-equilibrium setting. Retirement flexibility is often seen as a hedge against capital-market risks which

  16. Flexible Coupling Corrects Shaft Misalinements

    Science.gov (United States)

    Mayo, R. A.

    1983-01-01

    Proposed flexible coupling provides nearly error free measurements of shaft rotation in presence of misalinements between shaft and position sensing transducer. Intended to be used in situations in which input or output shaft is mounted on flexible joint. Its function is to insure equal input and output angular velocities by forcing input and output shafts to remain parallel.

  17. Cryogenic cooling system for HTS cable

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Shigeru [Taiyo Nippon Sanso, Tsukuba (Japan)

    2017-06-15

    Recently, Research and development activity of HTS (High Temperature Superconducting) power application is very progressive worldwide. Especially, HTS cable system and HTSFCL (HTS Fault current limiter) system are proceeding to practical stages. In such system and equipment, cryogenic cooling system, which makes HTS equipment cooled lower than critical temperature, is one of crucial components. In this article, cryogenic cooling system for HTS application, mainly cable, is reviewed. Cryogenic cooling system can be categorized into conduction cooling system and immersion cooling system. In practical HTS power application area, immersion cooling system with sub-cooled liquid nitrogen is preferred. The immersion cooling system is besides grouped into open cycle system and closed cycle system. Turbo-Brayton refrigerator is a key component for closed cycle system. Those two cooling systems are focused in this article. And, each design and component of the cooling system is explained.

  18. Microtextured Surfaces for Turbine Blade Impingement Cooling

    Science.gov (United States)

    Fryer, Jack

    2014-01-01

    Gas turbine engine technology is constantly challenged to operate at higher combustor outlet temperatures. In a modern gas turbine engine, these temperatures can exceed the blade and disk material limits by 600 F or more, necessitating both internal and film cooling schemes in addition to the use of thermal barrier coatings. Internal convective cooling is inadequate in many blade locations, and both internal and film cooling approaches can lead to significant performance penalties in the engine. Micro Cooling Concepts, Inc., has developed a turbine blade cooling concept that provides enhanced internal impingement cooling effectiveness via the use of microstructured impingement surfaces. These surfaces significantly increase the cooling capability of the impinging flow, as compared to a conventional untextured surface. This approach can be combined with microchannel cooling and external film cooling to tailor the cooling capability per the external heating profile. The cooling system then can be optimized to minimize impact on engine performance.

  19. The Application of Conversational Implicature in Doctor-Patient Conversation

    Institute of Scientific and Technical Information of China (English)

    GAO Chong

    2014-01-01

    The doctor-patient conversation is the major way of communication between doctors and patients. A good conversa-tion helps to construct a harmonious doctor-patient relationship. This paper attempts to analyze the doctor-patient conversation by applying the Theory of Conversational Implicature. The theory is accepted as the cooperative principle consisting of four max-ims:quantity, quality, relation, manner. This paper will analyse how the four maxims work and the violating of the maxims in the doctor-patient conversation. Through linguistic study of the conversation, we try to find out the problems in the doctor-patient conversation and to provide some directive linguistic suggestions to doctors and patients.

  20. Flexible Dye-Sensitized Solar Cell Based on Vertical ZnO Nanowire Arrays

    Directory of Open Access Journals (Sweden)

    Chu Sheng

    2011-01-01

    Full Text Available Abstract Flexible dye-sensitized solar cells are fabricated using vertically aligned ZnO nanowire arrays that are transferred onto ITO-coated poly(ethylene terephthalate substrates using a simple peel-off process. The solar cells demonstrate an energy conversion efficiency of 0.44% with good bending tolerance. This technique paves a new route for building large-scale cost-effective flexible photovoltaic and optoelectronic devices.

  1. Effective Charge Carrier Utilization in Photocatalytic Conversions.

    Science.gov (United States)

    Zhang, Peng; Wang, Tuo; Chang, Xiaoxia; Gong, Jinlong

    2016-05-17

    Continuous efforts have been devoted to searching for sustainable energy resources to alleviate the upcoming energy crises. Among various types of new energy resources, solar energy has been considered as one of the most promising choices, since it is clean, sustainable, and safe. Moreover, solar energy is the most abundant renewable energy, with a total power of 173 000 terawatts striking Earth continuously. Conversion of solar energy into chemical energy, which could potentially provide continuous and flexible energy supplies, has been investigated extensively. However, the conversion efficiency is still relatively low since complicated physical, electrical, and chemical processes are involved. Therefore, carefully designed photocatalysts with a wide absorption range of solar illumination, a high conductivity for charge carriers, a small number of recombination centers, and fast surface reaction kinetics are required to achieve a high activity. This Account describes our recent efforts to enhance the utilization of charge carriers for semiconductor photocatalysts toward efficient solar-to-chemical energy conversion. During photocatalytic reactions, photogenerated electrons and holes are involved in complex processes to convert solar energy into chemical energy. The initial step is the generation of charge carriers in semiconductor photocatalysts, which could be enhanced by extending the light absorption range. Integration of plasmonic materials and introduction of self-dopants have been proved to be effective methods to improve the light absorption ability of photocatalysts to produce larger amounts of photogenerated charge carriers. Subsequently, the photogenerated electrons and holes migrate to the surface. Therefore, acceleration of the transport process can result in enhanced solar energy conversion efficiency. Different strategies such as morphology control and conductivity improvement have been demonstrated to achieve this goal. Fine-tuning of the

  2. Mechanism Interpretation of the Biological Brain Cooling and Its Inspiration on Bionic Engineering

    Institute of Scientific and Technical Information of China (English)

    Xu Xue; Jing Liu

    2011-01-01

    The brain is one of the most important organs in a biological body which can only work in a relatively stable temperature range. However, many environmental factors in biosphere would cause cerebral temperature fluctuations. To sustain and regulate the brain temperature, many mechanisms of biological brain cooling have been evolved, including Selective Brain Cooling (SBC), cooling through surface water evaporation, respiration, behavior response and using special anatomical appendages. This article is dedicated to present a summarization and systematic interpretation on brain cooling strategies developed in animals by classifying and comparatively analyzing each typical biological brain cooling mechanism from the perspective of bio-heat transfer. Meanwhile, inspirations from such cooling in nature were proposed for developing advanced bionic engineering technologies especially with two focuses on therapeutic hypothermia and computer chip cooling areas. It is expected that many innovations can be achieved along this way to find out new cooling methodologies for a wide variety of industrial applications which will be highly efficient, energy saving, flexible or even intelligent.

  3. Functional aspects of protein flexibility

    DEFF Research Database (Denmark)

    Teilum, Kaare; Olsen, Johan G; Kragelund, Birthe B

    2009-01-01

    Proteins are dynamic entities, and they possess an inherent flexibility that allows them to function through molecular interactions within the cell, among cells and even between organisms. Appreciation of the non-static nature of proteins is emerging, but to describe and incorporate...... this into an intuitive perception of protein function is challenging. Flexibility is of overwhelming importance for protein function, and the changes in protein structure during interactions with binding partners can be dramatic. The present review addresses protein flexibility, focusing on protein-ligand interactions....... The thermodynamics involved are reviewed, and examples of structure-function studies involving experimentally determined flexibility descriptions are presented. While much remains to be understood about protein flexibility, it is clear that it is encoded within their amino acid sequence and should be viewed...

  4. Solar energy conversion

    CERN Document Server

    Likhtenshtein, Gertz I

    2012-01-01

    Finally filling a gap in the literature for a text that also adopts the chemist?s view of this hot topic, Prof Likhtenshtein, an experienced author and internationally renowned scientist, considers different physical and engineering aspects in solar energy conversion. From theory to real-life systems, he shows exactly which chemical reactions take place when converting light energy, providing an overview of the chemical perspective from fundamentals to molecular harvesting systems and solar cells. This essential guide will thus help researchers in academia and industry better understa

  5. Moodle 20 Course Conversion

    CERN Document Server

    Wild, Ian

    2011-01-01

    With clear instructions and plenty of screenshots, this book provides all the support and guidance you will need as you begin to convert your teaching to Moodle. Step-by-step tutorials use real-world examples to show you how to convert to Moodle in the most efficient and effective ways possible. Moodle Course Conversion carefully illustrates how Moodle can be used to teach content and ideas and clearly demonstrates the advantages of doing so. This book is for teachers, tutors, and lecturers who already have a large body of teaching material and want to use Moodle to enhance their course, rathe

  6. Cooperative internal conversion process

    CERN Document Server

    Kálmán, Péter

    2015-01-01

    A new phenomenon, called cooperative internal conversion process, in which the coupling of bound-free electron and neutron transitions due to the dipole term of their Coulomb interaction permits cooperation of two nuclei leading to neutron exchange if it is allowed by energy conservation, is discussed theoretically. General expression of the cross section of the process is reported in one particle nuclear and spherical shell models as well in the case of free atoms (e.g. noble gases). A half-life characteristic of the process is also determined. The case of $Ne$ is investigated numerically. The process may have significance in fields of nuclear waste disposal and nuclear energy production.

  7. Broadband frequency conversion

    DEFF Research Database (Denmark)

    Sanders, Nicolai Højer; Jensen, Ole Bjarlin; Dam, Jeppe Seidelin;

    that ensures phase matching over a broad spectral range in the BBO crystal. Since the tuning mechanism relies on all-passive components with extremely short response times the proposed method is well suited for short pulse, broad bandwidth laser sources like mode-locked lasers or super-continuum sources......We demonstrate a method for frequency conversion of broadly tunable or broad bandwidth light in a static, passive setup. Using simple optical components like lenses, mirrors and gratings and a BiBO crystal as the nonlinear material, we are able to frequency double a single-frequency, tunable...

  8. Catalytic Conversion of Carbohydrates

    DEFF Research Database (Denmark)

    Osmundsen, Christian Mårup

    . The synthesis of these by the cycloaddition of ethylene to furanic compounds, followed by dehydrative aromatization, was demonstrated in good yields, using a strong Brønsted acidic catalyst, WOx/ZrO2. As both ethylene and furanics can be derived from carbohydrates by known processes, this constitutes...... to be an efficient initial conversion step in the utilization of biomass for chemicals production. The shift from an oil based chemical industry to one based on renewable resources is bound to happen sooner or later, however the environmental problems associated with the burning of fossil resources means...

  9. Floor cooling and air-cooling, the effects on thermal comfort or different cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    Sijpheer, N.C.; Bakker, E.J.; Ligthart, F.A.T.M.; Opstelten, I.J. [ECN Energie in de Gebouwde Omgeving en Netten, Petten (Netherlands)

    2007-09-15

    One of the research areas of the Energy research Centre of the Netherlands (ECN) concerns the built environment. Several facilities to conduct research activities are at ECN's disposal. One of these facilities, are five research dwellings located on the premises of ECN. Measured data from these facilities together with weather data and computer models are used to evaluate innovative energy concepts and components in energy systems. Experiments with different cooling systems in ECN's research dwellings are executed to evaluate their effective influence on both energy use and thermal comfort. Influence of inhabitants' behaviour is taken into account in these experiments. The thermal comfort is indicated by the Predicted Mean Vote (PMV) as defined by P.O. Fanger. For this paper, the results of measurements with a floor cooling and air cooling system are assessed. Effects on the PMV measured during experiments with the two different cooling systems will be presented.

  10. [Flexible root posts].

    Science.gov (United States)

    Vadachkoriia, N R; Mandzhavidze, N A; Gumberidze, N Sh

    2009-02-01

    The article discusses the current state of restoration techniques of root canal treatment. Nowadays, technical progress allows manufacturers to develop flexible fiberglass posts, aspiring not only to an excellent aesthetics and mechanical properties (first of all, in comparison with metal and cast posts), but also to maintenance of their radio density and a wide range of forms. Growth of fiberglass posts popularity testifies to their clinical efficiency that also is confirmed by results of long-term researches. Introduction of fiberglass posts in a dental practice has rendered huge influence on restoration techniques of root canal treatment. Convincing factors of fiberglass posts superiority provide restoration the appearance similar with the natural dentition; possess close to dentine elasticity; creation of monolithic structure with hard tooth tissues and composite cement, posts, in case of need, can be easily adjusted on length, adhesive linkage of posts gives them additional stability. Modern researches have confirmed that only elastic, namely carbon fiber and the fiberglass posts made of modern technologies possess similar physical properties, as tooth structure. They can create reliable biomimetic design; solve a complex of aesthetic and functional restoration problems.

  11. Orthogonal flexible Rydberg aggregates

    Science.gov (United States)

    Leonhardt, K.; Wüster, S.; Rost, J. M.

    2016-02-01

    We study the link between atomic motion and exciton transport in flexible Rydberg aggregates, assemblies of highly excited light alkali-metal atoms, for which motion due to dipole-dipole interaction becomes relevant. In two one-dimensional atom chains crossing at a right angle adiabatic exciton transport is affected by a conical intersection of excitonic energy surfaces, which induces controllable nonadiabatic effects. A joint exciton-motion pulse that is initially governed by a single energy surface is coherently split into two modes after crossing the intersection. The modes induce strongly different atomic motion, leading to clear signatures of nonadiabatic effects in atomic density profiles. We have shown how this scenario can be exploited as an exciton switch, controlling direction and coherence properties of the joint pulse on the second of the chains [K. Leonhardt et al., Phys. Rev. Lett. 113, 223001 (2014), 10.1103/PhysRevLett.113.223001]. In this article we discuss the underlying complex dynamics in detail, characterize the switch, and derive our isotropic interaction model from a realistic anisotropic one with the addition of a magnetic bias field.

  12. Orthogonal flexible Rydberg aggregates

    CERN Document Server

    Leonhardt, K; Rost, J M

    2015-01-01

    We study the link between atomic motion and exciton transport in flexible Rydberg aggregates, assemblies of highly excited light alkali atoms, for which motion due to dipole-dipole interaction becomes relevant. In two one-dimensional atom chains crossing at a right angle adiabatic exciton transport is affected by a conical intersection of excitonic energy surfaces, which induces controllable non-adiabatic effects. A joint exciton/motion pulse that is initially governed by a single energy surface is coherently split into two modes after crossing the intersection. The modes induce strongly different atomic motion, leading to clear signatures of non-adiabatic effects in atomic density profiles. We have shown how this scenario can be exploited as an exciton switch, controlling direction and coherence properties of the joint pulse on the second of the chains [K.~Leonhardt {\\it et al.}, Phys.~Rev.~Lett. {\\bf 113} 223001 (2014)]. In this article we discuss the underlying complex dynamics in detail, characterise the ...

  13. Photoelectrochemical materials and energy conversion processes

    Energy Technology Data Exchange (ETDEWEB)

    Alkire, Richard C. [Illinois Univ., Urbana, IL (United States); Kolb, Dieter M. [Ulm Univ. (Germany). Inst. of Electrochemistry; Lipkowski, Jacek [Guelph Univ., Guelph, ON (Canada). Dept. of Chemistry; Ross, Philip N. (eds.) [Lawrence Berkeley National Laboratory, Berkeley, CA (United States). Materials Science Dept.

    2010-07-01

    This book focuses on the electrochemical science aspects associated with photonic phenomena, photovoltaic materials and systems, as well as the engineering fundamentals surrounding their fabrication processes and functional capabilities. It contains five main topics: 1. Applications of electrochemistry in the fabrication and characterization of thin film solar cells (P. Dale et al.); 2. Interfaces for the photoelectrochemical conversion of solar energy (H-J. Lewerenz); 3. Printable materials and technologies for dye-sensitized photovoltaic cells with flexible substrates (T. Miyasaka); 4. Electrodepostied porous ZnO sensitized by organic dyes - promising materials for dye-sensitized solar cells with potential application in large-scale photovoltaics (D. Schlettwein et al.); 5. Thin-film semiconductors deposited in nanometric scales by electrochemical and wet chemical methods for photovoltaic solar cell applications (O. Savadogo).

  14. Conversion program in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Jonsson, E.B. [Studsvik Nuclear AB, Nykoeping (Sweden)

    1997-08-01

    The conversion of the Swedish 50 MW R2 reactor from HEU to LEU fuel has been successfully accomplished over a 16 cycles long process. The conversion started in January 1991 with the introduction of 6 LEU assemblies in the 8*8 core. The first all LEU core was loaded in March 1993 and physics measurements were performed for the final licensing reports. A total of 142 LEU fuel assemblies have been irradiated up until September 1994 without any fuel incident. The operating licence for the R2 reactor was renewed in mid 1994 taking into account new fuel type. The Swedish Nuclear Inspectorate (SKI) pointed out one crucial problem with the LEU operation, that the back end of the LEU fuel cycle has not yet been solved. For the HEU fuel Sweden had the reprocessing alternative. The country is now relying heavily on the success of the USDOEs Off Site Fuels Policy to take back the spent fuel from the research reactors. They have in the meantime increased their intermediate storage facilities. There is, however, a limit both in time and space for storage of MTR-type of assemblies in water. The penalty of the lower thermal neutron flux in LEU cores has been reduced by improvements of the new irradiation rigs and by fine tuning the core calculations. The Studsvik code package, CASMO-SIMULATE, widely used for ICFM in LWRs has been modified to suit the compact MTR type of core.

  15. Equipment for gas conversion

    Energy Technology Data Exchange (ETDEWEB)

    Tabata, K.; Matsumoto, I.

    1983-01-28

    Equipment is proposed for vapor conversion of hydrocarbons (Uv), possibly in a mixture with air, in order to produce an inorganic gas, which chiefly consists of H2 and COx. It consists of a reaction pipe made of an inorganic refractory ceramic and equipped along the wall circumference with heaters. The reaction pipe is filled with a combined, multilayer catalyst (Kt) carrier, made of gamma-A1203 which in the transverse cross section has a multipore reticular or fibrous structure. Replacement of the traditional steel (St) materials for the walls of the reaction pipe with ceramic materials reduces the output of the hydrocarbon which contaminates the surface (Pv) of the catalyst; the use of a multilayer carrier for the catalyst made of gamma-A1203 with a porous reticular or fibrous structure reduces the pressure losses in the reactor and facilitates the replacement of the spent catalyst. The equipment is designed for vapor conversion of natural gas, C3H8, and vapors of kerosene, naphtha and so on.

  16. Alpha and conversion electron spectroscopy of 238,239Pu and 241Am and alpha-conversion electron coincidence measurements

    Science.gov (United States)

    Dion, Michael P.; Miller, Brian W.; Warren, Glen A.

    2016-09-01

    A technique to determine the isotopic constituents of a mixed actinide sample has been proposed by a coincident alpha-conversion electron measurement. This presents a unique signature to allow the unfolding of isotopes that possess overlapping alpha particle energy and reduce backgrounds of an unseparated sample. The work presented here are results of conversion electron spectroscopy of 241Am, 238Pu and 239Pu using a dual-stage peltier-cooled 25 mm2 silicon drift detector and alpha spectroscopy with a passivated ion implanted planar silicon detector. The conversion electron spectra were evaluated from 20-55 keV based on fits to the dominant conversion electron emissions, which allowed the relative conversion electron emission intensities to be determined. These measurements provide crucial singles spectral information and calibration to aid in the coincident measurement approach. Furthermore, an alpha-conversion electron spectrometer was assembled using the silicon based detectors described and results of a coincident spectrum analysis is reported for 241Am.

  17. High conversion efficiency in resonant four-wave mixing processes.

    Science.gov (United States)

    Lee, Chin-Yuan; Wu, Bo-Han; Wang, Gang; Chen, Yong-Fang; Chen, Ying-Cheng; Yu, Ite A

    2016-01-25

    We propose a new scheme of the resonant four-wave mixing (FWM) for the frequency up or down conversion, which is more efficient than the commonly-used scheme of the non-resonant FWM. In this new scheme, two control fields are spatially varied such that a probe field at the input can be converted to a signal field at the output. The efficiency of probe-to-signal energy conversion can be 90% at medium's optical depth of about 100. Our proposed scheme works for both the continuous-wave and pulse cases, and is flexible in choosing the control field intensity. This work provides a very useful tool in the nonlinear frequency conversion.

  18. A Closed Brayton Power Conversion Unit Concept for Nuclear Electric Propulsion for Deep Space Missions

    Science.gov (United States)

    Joyner, Claude Russell; Fowler, Bruce; Matthews, John

    2003-01-01

    In space, whether in a stable satellite orbit around a planetary body or traveling as a deep space exploration craft, power is just as important as the propulsion. The need for power is especially important for in-space vehicles that use Electric Propulsion. Using nuclear power with electric propulsion has the potential to provide increased payload fractions and reduced mission times to the outer planets. One of the critical engineering and design aspects of nuclear electric propulsion at required mission optimized power levels is the mechanism that is used to convert the thermal energy of the reactor to electrical power. The use of closed Brayton cycles has been studied over the past 30 or years and shown to be the optimum approach for power requirements that range from ten to hundreds of kilowatts of power. It also has been found to be scalable to higher power levels. The Closed Brayton Cycle (CBC) engine power conversion unit (PCU) is the most flexible for a wide range of power conversion needs and uses state-of-the-art, demonstrated engineering approaches. It also is in use with many commercial power plants today. The long life requirements and need for uninterrupted operation for nuclear electric propulsion demands high reliability from a CBC engine. A CBC engine design for use with a Nuclear Electric Propulsion (NEP) system has been defined based on Pratt & Whitney's data from designing long-life turbo-machines such as the Space Shuttle turbopumps and military gas turbines and the use of proven integrated control/health management systems (EHMS). An integrated CBC and EHMS design that is focused on using low-risk and proven technologies will over come many of the life-related design issues. This paper will discuss the use of a CBC engine as the power conversion unit coupled to a gas-cooled nuclear reactor and the design trends relative to its use for powering electric thrusters in the 25 kWe to 100kWe power level.

  19. Thermal behavior in the cracking reaction zone of scramjet cooling channels at different channel aspect ratios

    Science.gov (United States)

    Zhang, Silong; Feng, Yu; Jiang, Yuguang; Qin, Jiang; Bao, Wen; Han, Jiecai; Haidn, Oskar J.

    2016-10-01

    To study the thermal behavior in the cracking reaction zone of regeneratively cooled scramjet cooling channels at different aspect ratios, 3-D model of fuel flow in terms of the fuel's real properties and cracking reaction is built and validated through experiments. The whole cooling channel is divided into non-cracking and cracking reaction zones. Only the cracking reaction zone is studied in this article. The simulation results indicate that the fuel conversion presents a similar distribution with temperature because the fuel conversion in scramjet cooling channels is co-decided by the temperature and velocity but the temperature plays the dominate role. For the cases given in this paper, increasing the channel aspect ratio will increase the pressure drop and it is not beneficial for reducing the wall temperature because of the much severer thermal stratification, larger conversion non-uniformity, the corresponding M-shape velocity profile which will cause local heat transfer deterioration and the decreased chemical heat absorption. And the decreased chemical heat absorption caused by stronger temperature and conversion non-uniformities is bad for the utilization of chemical heat sink, chemical recuperation process and the ignition performance.

  20. Bunched Beam Cooling in the Fermilab Recycler

    CERN Document Server

    Neuffer, David V; Burov, Alexey; Nagaitsev, Sergei

    2005-01-01

    Stochastic cooling with bunched beam in a linear bucket has been obtained and implemented operationally in the fermilab recycler. In this implementation the particle bunch length is much greater than the cooling system wavelengths. The simultaneous longitudinal bunching enables cooling to much smaller longitudinal emittances than the coasting beam or barrier bucket system. Characteristics and limitations of bunched beam stochastic cooling are discussed.

  1. A new Newton's law of cooling?

    Science.gov (United States)

    Kleiber, M

    1972-12-22

    Several physiologists confuse Fourier's law of animal heat flow with Newton's law of cooling. A critique of this error in 1932 remained ineffective. In 1969 Molnar tested Newton's cooling law. In 1971 Strunk found Newtonian cooling unrealistic for animals. Unfortunately, he called the Fourier formulation of animal heat flow, requiring post-Newtonian observations, a "contemporary Newtonian law of cooling."

  2. 14 CFR 25.1043 - Cooling tests.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling tests. 25.1043 Section 25.1043... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Cooling § 25.1043 Cooling tests. (a) General. Compliance... during the cooling tests must be the minimum grade approved for the engines, and the mixture...

  3. 14 CFR 27.1043 - Cooling tests.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling tests. 27.1043 Section 27.1043... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Cooling § 27.1043 Cooling tests. (a) General. For the tests... during the cooling tests must be of the minimum grade approved for the engines, and the mixture...

  4. 14 CFR 29.1043 - Cooling tests.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling tests. 29.1043 Section 29.1043... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Cooling § 29.1043 Cooling tests. (a) General. For the... (a)(1) of this section may exceed established limits. (3) The fuel used during the cooling tests...

  5. 14 CFR 29.908 - Cooling fans.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling fans. 29.908 Section 29.908... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant General § 29.908 Cooling fans. For cooling fans that are a part of a powerplant installation the following apply: (a) Category A. For cooling fans...

  6. 14 CFR 23.1043 - Cooling tests.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling tests. 23.1043 Section 23.1043... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1043 Cooling... established limits. (3) The fuel used during the cooling tests must be of the minimum grade approved for...

  7. Impingement jet cooling in gas turbines

    CERN Document Server

    Amano, R S

    2014-01-01

    Due to the requirement for enhanced cooling technologies on modern gas turbine engines, advanced research and development has had to take place in field of thermal engineering. Impingement jet cooling is one of the most effective in terms of cooling, manufacturability and cost. This is the first to book to focus on impingement cooling alone.

  8. Flexible Blades for Wind Turbines

    Science.gov (United States)

    Collins, Madeline Carlisle; Macphee, David; Harris, Caleb

    2016-11-01

    Previous research has shown that windmills with flexible blades are more efficient than those with rigid blades. Flexibility offers passive pitch control, preferable to active pitch control which is costly and requires maintenance. Flexible blades morph such that the blade more closely resembles its design point at part load and over load. The lift-to-drag ratios on individual blades was investigated. A mold was designed and machined from an acrylic slab for the casting of blades with a NACA 0012 cross section. A flexible blade was cast from silicone and a rigid blade was cast from polyurethane. Each of these blades was tested in a wind tunnel, cantilever mounted, spanning the whole test section. The angle of attack was varied by rotating the mount. All tests were performed at the same wind speed. A load cell within the mount measured forces on the blade, from which the lift and drag forces were calculated. The stall point for the flexible blade occurred later than for the rigid blade, which agrees with previous research. Lift-to-drag ratios were larger for the flexible blade at all angles of attack tested. Flexible blades seem to be a viable option for passive pitch control. Future research will include different airfoil cross sections, wind speeds, and blade materials. Funding from NSF REU site Grant EEC 1358991 is greatly appreciated.

  9. Swarming: flexible roaming plans.

    Science.gov (United States)

    Partridge, Jonathan D; Harshey, Rasika M

    2013-03-01

    Movement over an agar surface via swarming motility is subject to formidable challenges not encountered during swimming. Bacteria display a great deal of flexibility in coping with these challenges, which include attracting water to the surface, overcoming frictional forces, and reducing surface tension. Bacteria that swarm on "hard" agar surfaces (robust swarmers) display a hyperflagellated and hyperelongated morphology. Bacteria requiring a "softer" agar surface (temperate swarmers) do not exhibit such a dramatic morphology. For polarly flagellated robust swarmers, there is good evidence that restriction of flagellar rotation somehow signals the induction of a large number of lateral flagella, but this scenario is apparently not relevant to temperate swarmers. Swarming bacteria can be further subdivided by their requirement for multiple stators (Mot proteins) or a stator-associated protein (FliL), secretion of essential polysaccharides, cell density-dependent gene regulation including surfactant synthesis, a functional chemotaxis signaling pathway, appropriate cyclic (c)-di-GMP levels, induction of virulence determinants, and various nutritional requirements such as iron limitation or nitrate availability. Swarming strategies are as diverse as the bacteria that utilize them. The strength of these numerous designs stems from the vantage point they offer for understanding mechanisms for effective colonization of surface niches, acquisition of pathogenic potential, and identification of environmental signals that regulate swarming. The signature swirling and streaming motion within a swarm is an interesting phenomenon in and of itself, an emergent behavior with properties similar to flocking behavior in diverse systems, including birds and fish, providing a convenient new avenue for modeling such behavior.

  10. Flexible armored blanket development

    Energy Technology Data Exchange (ETDEWEB)

    Roth, E.S.

    1978-05-01

    An exploratory development contract was undertaken on December 23, 1977 which had as its purpose the development and demonstration of a flexible armored blanket design suitable for providing ballistic protection to nuclear weapons during shipment. Objectives were to design and fabricate a prototype blanket which will conform to the weapon shape, is troop-handleable in the field, and which, singly or in multiple layers, can defeat a range of kinetic energy armor piercing (AP) ammunition potentially capable of damaging the critical portion of the nuclear weapon. Following empirical testing, including the firing of threat ammunition under controlled laboratory and field test conditions, materials were selected and assembled into two blanket designs, each weighing approximately 54 kg/m{sup 2} (11 lbs/ft{sup 2}) and estimated to cost from $111 to $180 per ft{sup 2} in production. A firing demonstration to evidence blanket performance against terrorist/light infantry weapons, heavy infantry weapons, and aircraft cannon was conducted for representatives of the DOD and interested Sandia employees on April 12, 1978. The blankets performed better than anticipated defeating bullets up to 7.62 mm x 51 mm AP with one layer and projectiles up to 23 mm HEI with two layers. Based on these preliminary tests it is recommended that development work be continued with the following objectives: (1) the selection by the DOD of priority applications, (2) the specific design and fabrication of sufficient quantities of armored blankets for field testing, (3) the evaluation of the blankets by DOD operational units, with reports to Sandia Laboratories to enable final design.

  11. Turbulence convective heat transfer for cooling the photovoltaic cells

    Science.gov (United States)

    Arianmehr, Iman

    Solar PV (photovoltaic) is a rapidly advancing renewable energy technology which converts sunlight directly into electricity. One of the outstanding challenges of the current PV technology is the reduction in its conversion efficiency with increasing PV panel temperature, which is closely associated with the increase in solar intensity and the ambient temperature surrounding the PV panels. To more effectively capture the available energy when the sun is most intense, significant efforts have been invested in active and passive cooling research over the last few years. While integrated cooling systems can lead to the highest total efficiencies, they are usually neither the most feasible nor the most cost effective solutions. This work examines some simple passive means of manipulating the prevailing wind turbulence to enhance convective heat transfer over a heated plate in a wind tunnel.

  12. New cooling regulation technology of secondary cooling station in DCS

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Xuan; Yan, Jun-wei; Zhu, Dong-sheng; Liu, Fei-long; Lei, Jun-xi [The Key Lab of Enhanced Heat Transfer and Energy Conservation of Ministry of Education, School of Chemical and Energy Engineering, South China University of Technology, Guangzhou 510641 (China); Liang, Lie-quan [The Key Lab of E-Commerce Market Application Technology of Guangdong Province, Guangdong University of Business Studies, Guangzhou 510320 (China)

    2008-07-01

    In this paper, a kind of new control technology of secondary cooling station (constant flow rate/variable temperature difference) in district cooling system (DCS) is proposed in view of serial consequences including low efficiency and high operating cost caused by low temperature of supply water in DCS. This technology has been applied in DCS of Guangzhou University City. The result has already indicated that such technology can increase the supply and return temperatures of buildings, return water temperature of primary side in the plate heat exchanger unit, moreover, the efficiency of both the chiller and the whole system are improved significantly. (author)

  13. Cooling Efficiency of Laminar Cooling System for Plate Mill

    Institute of Scientific and Technical Information of China (English)

    ZHANG Dian-hua; WANG Bing-xing; ZHOU Na; YU Ming; WANG Jun

    2008-01-01

    Heat transfer was researched from a perspective of the industry application.On the basis of the first law of thermodynamics,the cooling efficiency was deduced from the change of enthalpy inside hot plate.The relationship between the cooling efficiency and its influencing parameters was regressed from plenty of data collected from the worksite and discussed in detail.The temperature profiles resulting from the online model and the model modified by regressed formulas were presented and compared.The results indicated that the control accuracy of the modified model was increased obviously.

  14. Direct energy conversion using liquid metals

    Directory of Open Access Journals (Sweden)

    Onea Alexandru

    2014-01-01

    Full Text Available Liquid metals have excellent properties to be used as heat transport fluids due to their high thermal conductivity and their wide applicable temperature range. The latter issue can be used to go beyond limitations of existing thermal solar energy systems. Furthermore, the direct energy converter Alkali Metal Thermo Electric Converter (AMTEC can be used to make intangible areas of energy conversion suitable for a wide range of applications. One objective is to investigate AMTEC as a complementary cycle for the next generation of concentrating solar power (CSP systems. The experimental research taking place in the Karlsruhe Institute of Technology (KIT is focused on the construction of a flexible AMTEC test facility, development, test and improvement of liquid-anode and vapor-anode AMTEC devices as well as the coupling of the AMTEC cold side to the heat storage tank proposed for the CSP system. Within this project, the investigations foreseen will focus on the analyses of BASE-metal interface, electrode materials and deposition techniques, corrosion and erosion of materials brought in contact with high temperature sodium. This prototype demonstrator is planned to be integrated in the KArlsruhe SOdium LAboratory (KASOLA, a flexible closed mid-size sodium loop, completely in-house designed, presently under construction at the Institute for Neutron Physics and Reactor Technology (INR within KIT.

  15. Direct energy conversion using liquid metals

    Science.gov (United States)

    Onea, Alexandru; Diez de los Rios Ramos, Nerea; Hering, Wolfgang; Stieglitz, Robert; Moster, Peter

    2014-12-01

    Liquid metals have excellent properties to be used as heat transport fluids due to their high thermal conductivity and their wide applicable temperature range. The latter issue can be used to go beyond limitations of existing thermal solar energy systems. Furthermore, the direct energy converter Alkali Metal Thermo Electric Converter (AMTEC) can be used to make intangible areas of energy conversion suitable for a wide range of applications. One objective is to investigate AMTEC as a complementary cycle for the next generation of concentrating solar power (CSP) systems. The experimental research taking place in the Karlsruhe Institute of Technology (KIT) is focused on the construction of a flexible AMTEC test facility, development, test and improvement of liquid-anode and vapor-anode AMTEC devices as well as the coupling of the AMTEC cold side to the heat storage tank proposed for the CSP system. Within this project, the investigations foreseen will focus on the analyses of BASE-metal interface, electrode materials and deposition techniques, corrosion and erosion of materials brought in contact with high temperature sodium. This prototype demonstrator is planned to be integrated in the KArlsruhe SOdium LAboratory (KASOLA), a flexible closed mid-size sodium loop, completely in-house designed, presently under construction at the Institute for Neutron Physics and Reactor Technology (INR) within KIT.

  16. Personal cooling apparatus and method

    Energy Technology Data Exchange (ETDEWEB)

    Siman-Tov, Moshe (Knoxville, TN); Crabtree, Jerry Allen (Knoxville, TN)

    2001-01-01

    A portable lightweight cooling apparatus for cooling a human body is disclosed, having a channeled sheet which absorbs sweat and/or evaporative liquid, a layer of highly conductive fibers adjacent the channeled sheet; and, an air-moving device for moving air through the channeled sheet, wherein the layer of fibers redistributes heat uniformly across the object being cooled, while the air moving within the channeled sheet evaporates sweat and/or other evaporative liquid, absorbs evaporated moisture and the uniformly distributed heat generated by the human body, and discharges them into the environment. Also disclosed is a method for removing heat generated by the human body, comprising the steps of providing a garment to be placed in thermal communication with the body; placing a layer of highly conductive fibers within the garment adjacent the body for uniformly distributing the heat generated by the body; attaching an air-moving device in communication with the garment for forcing air into the garment; removably positioning an exchangeable heat sink in communication with the air-moving device for cooling the air prior to the air entering the garment; and, equipping the garment with a channeled sheet in communication with the air-moving device so that air can be directed into the channeled sheet and adjacent the layer of fibers to expell heat and moisture from the body by the air being directed out of the channeled sheet and into the environment. The cooling system may be configured to operate in both sealed and unsealed garments.

  17. Oxygen Absorption in Cooling Flows.

    Science.gov (United States)

    Buote

    2000-04-01

    The inhomogeneous cooling flow scenario predicts the existence of large quantities of gas in massive elliptical galaxies, groups, and clusters that have cooled and dropped out of the flow. Using spatially resolved, deprojected X-ray spectra from the ROSAT PSPC, we have detected strong absorption over energies approximately 0.4-0.8 keV intrinsic to the central approximately 1&arcmin; of the galaxy NGC 1399, the group NGC 5044, and the cluster A1795. These systems have among the largest nearby cooling flows in their respective classes and low Galactic columns. Since no excess absorption is indicated for energies below approximately 0.4 keV, the most reasonable model for the absorber is warm, collisionally ionized gas with T=105-106 K in which ionized states of oxygen provide most of the absorption. Attributing the absorption only to ionized gas reconciles the large columns of cold H and He inferred from Einstein and ASCA with the lack of such columns inferred from ROSAT and also is consistent with the negligible atomic and molecular H inferred from H i and CO observations of cooling flows. The prediction of warm ionized gas as the product of mass dropout in these and other cooling flows can be verified by Chandra and X-Ray Multimirror Mission.

  18. Axion Cooling of Neutron Stars

    CERN Document Server

    Sedrakian, Armen

    2015-01-01

    Cooling simulations of neutron stars and their comparison with the data from thermally emitting X-ray sources puts constraints on the properties of axions, and by extension of any light pseudo-scalar dark matter particles, whose existence has been postulated to solve the strong-CP problem of QCD. We incorporate the axion emission by pair-breaking and formation processes by $S$- and $P$-wave nucleonic condensates in a benchmark code for cooling simulations as well as provide fit formulae for the rates of these processes. Axion cooling of neutron stars has been simulated for 24 models covering the mass range 1 to 1.8 solar masses, featuring non-accreted iron and accreted light element envelopes, and a range of nucleon-axion coupling. The models are based on an equation state predicting conservative physics of superdense nuclear matter that does not allow for onset of fast cooling processes induced by phase transitions to non-nucleonic forms of matter or high proton concentration. The cooling tracks in the tempe...

  19. Catalytic Hydrothermal Conversion of Wet Biomass Feedstocks and Upgrading – Process Design and Optimization

    DEFF Research Database (Denmark)

    Hoffmann, Jessica; Toor, Saqib; Rosendahl, Lasse

    Liquid biofuels will play a major role for a more sustainable energy system of the future. The CatLiq® process is a 2nd generation biomass conversion process that is based on hydrothermal liquefaction. Hydrothermal liquefaction offers a very efficient and feedstock flexible way of converting...... biomass to bio-oil. Bio-oils from hydrothermal liquefaction are characterised by their high feedstock flexibility. Upgrading of complete bio-oils derived from hydrothermal conversion has not yet been extensively studied. Purpose of this work is to reduce the oxygen content of the bio-oil to improve...

  20. A Conceptual Study on a Supercritical CO2-cooled KAIST Micro Modular Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yu, HwanYeal; Hartanto, Donny; Kim, Yonghee [KAIST, Daejeon (Korea, Republic of)

    2015-05-15

    Small Modular Reactors (SMRs) are nuclear reactors that are completely built in a factory and shipped to the designated site for installation. As such, the SMR is especially advantageous as a flexible and cost-effective energy source for remote and isolated areas. Furthermore, the concept requires a relatively low capital cost, which makes it attractive for developing countries with limited electricity grid. In addition, the SMR concepts also generate more interest after the Fukushima accident since it can easily be designed with a passive decay heat removal system. One of the major advantages of a water-cooled SMR is its relatively small core size. Nonetheless, in spite of its small core size, the volume and area required for its steam-cycle power conversion unit is still significant. In this study, neutronics feasibility of a fully compact and transportable KAIST micro-modular reactor (MMR) was demonstrated. Rated thermal power of the core was 36.2 MWth with total weight of about 39.6 tons. The core was loaded with 15.5 w/o uranium mono-nitride U15N fuels in order to achieve a targeted lifetime of 20 EFPYs. To achieve targeted lifetime, initial excess reactivity of the core should be quite high, around 4,707 pcm. To reduce the high excess reactivity to about 2,500 pcm, a replaceable burnable absorber was utilized in the design. As a result, the MMR has a 20-year lifetime with a relatively small burnup reactivity swing. Several important safety parameters of the KAIST MMR core were also determined in this study. The Doppler reactivity coefficients and CVRs were demonstrated to negative. Worth of the primary control drums and secondary control rod were much higher than initial excess reactivity.

  1. Printable, flexible and stretchable diamond for thermal management

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, John A; Kim, Tae Ho; Choi, Won Mook; Kim, Dae Hyeong; Meitl, Matthew; Menard, Etienne; Carlisle, John

    2013-06-25

    Various heat-sinked components and methods of making heat-sinked components are disclosed where diamond in thermal contact with one or more heat-generating components are capable of dissipating heat, thereby providing thermally-regulated components. Thermally conductive diamond is provided in patterns capable of providing efficient and maximum heat transfer away from components that may be susceptible to damage by elevated temperatures. The devices and methods are used to cool flexible electronics, integrated circuits and other complex electronics that tend to generate significant heat. Also provided are methods of making printable diamond patterns that can be used in a range of devices and device components.

  2. Computer Aided Design of The Cooling System for Plastic Injection Molds

    Directory of Open Access Journals (Sweden)

    Hakan GÜRÜN

    2009-02-01

    Full Text Available The design of plastic injection molds and their cooling systems affect both the dimension, the shape, the quality of a plastic part and the cycle time of process and the cost of mold. In this study, the solid model design of a plastic injection mold and the design of cooling sysytem were possibly carried out without the designer interaction. Developed program permited the use of three types of the cooling system and the different cavity orientations and the multible plastic part placement into the mold cores. The program which was developed by using Visual LISP language and the VBA (Visual BASIC for Application modules, was applicated in the AutoCAD software domain. Trial studies were presented that the solid model design of plastic injection molds and the cooling systems increased the reliability, the flexibility and the speed of the design.

  3. Guideline Implementation: Processing Flexible Endoscopes.

    Science.gov (United States)

    Bashaw, Marie A

    2016-09-01

    The updated AORN "Guideline for processing flexible endoscopes" provides guidance to perioperative, endoscopy, and sterile processing personnel for processing all types of reusable flexible endoscopes and accessories in all procedural settings. This article focuses on key points of the guideline to help perioperative personnel safely and effectively process flexible endoscopes to prevent infection transmission. The key points address verification of manual cleaning, mechanical cleaning and processing, storage in a drying cabinet, determination of maximum storage time before reprocessing is needed, and considerations for implementing a microbiologic surveillance program. Perioperative RNs should review the complete guideline for additional information and for guidance when writing and updating policies and procedures.

  4. Flexible Learning in a Digital World.

    Science.gov (United States)

    Collis, Betty; Moonen, Jef

    2002-01-01

    Defines flexible learning and describes components of flexible learning in higher education, including technology, pedagogy or instructional approach, implementation strategies, and institutional framework. Considers factors constraining learning flexibility; changing student characteristics; and the need for lifelong learning, particularly in the…

  5. Power conversion technologies

    Energy Technology Data Exchange (ETDEWEB)

    Newton, M. A.

    1997-02-01

    The Power Conversion Technologies thrust area identifies and sponsors development activities that enhance the capabilities of engineering at Lawrence Livermore National Laboratory (LLNL) in the area of solid- state power electronics. Our primary objective is to be a resource to existing and emerging LLNL programs that require advanced solid-state power electronic technologies.. Our focus is on developing and integrating technologies that will significantly impact the capability, size, cost, and reliability of future power electronic systems. During FY-96, we concentrated our research efforts on the areas of (1) Micropower Impulse Radar (MIR); (2) novel solid-state opening switches; (3) advanced modulator technology for accelerators; (4) compact accelerators; and (5) compact pulse generators.

  6. Conversations About Responsible Nanoresearch.

    Science.gov (United States)

    Kjølberg, Kamilla Lein; Strand, Roger

    2011-04-01

    There is currently a strong focus on responsible research in relation to the development of nanoscience and nanotechnology. This study presents a series of conversations with nanoresearchers, with the 'European Commission recommendation on a code of conduct for responsible nanosciences and nanotechnologies research' (EC-CoC) as its point of departure. Six types of reactions to the document are developed, illustrating the diversity existing within the scientific community in responses towards this kind of new approaches to governance. Three broad notions of responsible nanoresearch are presented. The article concludes by arguing that while the suggestion put forward in the EC-CoC brings the concept of responsible nanoresearch a long way, one crucial element is to be wanted, namely responsible nanoresearch as increased awareness of moral choices.

  7. Conversation with Meir Sternberg

    Directory of Open Access Journals (Sweden)

    Federico Pianzola

    2011-07-01

    Full Text Available Below are the videos of the interview recorded the 21st May 2011 in Fribourg (CH, in occasion of the first RRN conference.Conversation with Meir Sternberg.Part 1 of 8 - Narratology: classical and postclassical studies. Part 2 of 8 - The development of an original theoretical framework. Part 3 of 8 - Sternberg and Genette: different ways for the same problems. Part 4 of 8 - «There are no forms except in terms of functions». Part 5 of 8 - A life writing articles: so many papers and just four books. Part 6 of 8 - Two arguments against mimetical approaches to narrative. Part 7 of 8 - «Narrative is not given, it is a construct». Part 8 of 8 - The proteus principle. the many-to-many correspondence between forms and functions.

  8. Thermodynamics and energy conversion

    CERN Document Server

    Struchtrup, Henning

    2014-01-01

    This textbook gives a thorough treatment of engineering thermodynamics with applications to classical and modern energy conversion devices.   Some emphasis lies on the description of irreversible processes, such as friction, heat transfer and mixing, and the evaluation of the related work losses. Better use of resources requires high efficiencies, therefore the reduction of irreversible losses should be seen as one of the main goals of a thermal engineer. This book provides the necessary tools.   Topics include: car and aircraft engines,  including Otto, Diesel and Atkinson cycles, by-pass turbofan engines, ramjet and scramjet;  steam and gas power plants, including advanced regenerative systems, solar tower, and compressed air energy storage; mixing and separation, including reverse osmosis, osmotic powerplants, and carbon sequestration; phase equilibrium and chemical equilibrium, distillation, chemical reactors, combustion processes, and fuel cells; the microscopic definition of entropy.    The book i...

  9. Cool Stars and Space Weather

    CERN Document Server

    Vidotto, A A; Cameron, A C; Morin, J; Villadsen, J; Saar, S; Alvarado, J; Cohen, O; Holzwarth, V; Poppenhaeger, K; Reville, V

    2014-01-01

    Stellar flares, winds and coronal mass ejections form the space weather. They are signatures of the magnetic activity of cool stars and, since activity varies with age, mass and rotation, the space weather that extra-solar planets experience can be very different from the one encountered by the solar system planets. How do stellar activity and magnetism influence the space weather of exoplanets orbiting main-sequence stars? How do the environments surrounding exoplanets differ from those around the planets in our own solar system? How can the detailed knowledge acquired by the solar system community be applied in exoplanetary systems? How does space weather affect habitability? These were questions that were addressed in the splinter session "Cool stars and Space Weather", that took place on 9 Jun 2014, during the Cool Stars 18 meeting. In this paper, we present a summary of the contributions made to this session.

  10. Quench cooling under reduced gravity

    CERN Document Server

    Chatain, D; Nikolayev, V S; Beysens, D

    2013-01-01

    We report the quench cooling experiments performed with liquid O2 under different levels of gravity simulated with the magnetic gravity compensation. A copper disk is quenched from 270K to 90K. It is found that the cooling time in microgravity is very long in comparison with any other gravity level. This phenomenon is explained by the isolation effect of the gas surrounding the disk. The liquid subcooling is shown to drastically improuve the heat exchange thus reducing the cooling time (about 20 times). The effect of subcooling on the heat transfer is analyzed at different gravity levels. It is shown that such type of experiments cannot be used for the analysis of the critical heat flux (CHF) of the boiling crisis. The minimum heat flux (MHF) of boiling is analyzed instead.

  11. Hybrid staging of geothermal energy conversion processes

    Energy Technology Data Exchange (ETDEWEB)

    Steidel, R.F.

    1978-09-01

    A hybrid system consists of two or more energy conversion processes. This study examines the use of three energy conversion machines in hybrid systems: the conventional single-phase turbine, and the two-phase expanders known as the Lysholm engine and the radial outflow reaction turbine. Two hybrid systems are presented. The first is a two-stage, single-flash system with the Lysholm engine as the first stage, and a separator and conventional turbine as the second stage. The second system adds a radial outflow reaction turbine to recover a part of the energy rejected in the second stage. A theoretical specific power of 41.3 kW.s/lb is predicted for the two-stage, single-flash hybrid system. The addition of the radial outflow rotary turbine increases performance to 44.8 kW.s/lb. Both are superior to the double-flash system, with a specific power of 37.8 kW.s/lb. In addition, the hybrid system offers operating flexibility.

  12. The effect of pre-cooling intensity on cooling efficiency and exercise performance

    NARCIS (Netherlands)

    Bogerd, N.; Perret, C.; Bogerd, C.P.; Rossi, R.M.; Daanen, H.A.M.

    2010-01-01

    Although pre-cooling is known to enhance exercise performance, the optimal cooling intensity is unknown. We hypothesized that mild cooling opposed to strong cooling circumvents skin vasoconstriction and thermogenesis, and thus improves cooling efficiency reflected in improved time to exhaustion. Eig

  13. A positive mood, a flexible brain

    OpenAIRE

    Betzel, Richard F.; Satterthwaite, Theodore D.; Gold, Joshua I.; Bassett, Danielle S.

    2016-01-01

    Flexible reconfiguration of human brain networks supports cognitive flexibility and learning. However, modulating flexibility to enhance learning requires an understanding of the relationship between flexibility and brain state. In an unprecedented longitudinal data set, we investigate the relationship between flexibility and mood, demonstrating that flexibility is positively correlated with emotional state. Our results inform the modulation of brain state to enhance response to training in h...

  14. Advances in Laser Cooling of Thulium-Doped Glass

    Science.gov (United States)

    2003-05-01

    conversion,’’ Appl. Phys. Lett. 75, 1258–1260 (1999). 21. L. Wetenkamp, G. F. West, and H. Tobben, ‘‘Optical proper- ties of rare earth-doped ZBLAN glasses ...properties of Tm31 in ZBLAN fluoride glass . Part 2. Judd-Ofelt parameters,’’ Phys. Chem. Glasses 36, 139–140 (1995). 38. M. J. Weber, ‘‘Laser excited...Advances in laser cooling of thulium-doped glass C. W. Hoyt, M. P. Hasselbeck, and M. Sheik-Bahae Department of Physics and Astronomy, University of

  15. SnO2-microtube-assembled cloth for fully flexible self-powered photodetector nanosystems.

    Science.gov (United States)

    Hou, Xiaojuan; Liu, Bin; Wang, Xianfu; Wang, Zhuoran; Wang, Qiufan; Chen, Di; Shen, Guozhen

    2013-09-01

    Integrating an energy conversion or storage device with photodetectors into a self-powered system provides a promising route to future devices aimed at reduced size, low weight and high flexibility. We reported here the fabrication of a fully flexible self-powered photodetector nanosystem by integrating a flexible SnO2-cloth-based ultraviolet photodetector with a flexible SnO2-cloth-based lithium-ion battery. The flexible SnO2-cloth-based ultraviolet photodetectors showed fast response to ultraviolet light with excellent flexibility and stability. Using SnO2-on-carbon-cloth as the binder-free anode and commercial LiCoO2/Al foil as the cathode, a flexible full lithium-ion battery was assembled, exhibiting a reversible capacity of 550 mA h g(-1) even after 60 cycles at a current density of 200 mA g(-1) in a potential window of 2-3.8 V. When integrated with and driven by the flexible full battery, the fully flexible self-powered photodetector nanosystem exhibits comparable performance with an analogous externally powered device. Such an integrated nanosystem could serve as a wireless detecting system in large areas, as required in applications such as environmental sensing and biosensing.

  16. A flexible and low cost experimental stand for air source heat pump for Smart Buildings

    DEFF Research Database (Denmark)

    Crăciun, Vasile S.; Bojesen, Carsten; Blarke, Morten

    2012-01-01

    prices. A significant part of this challenge may be dealt with in the way space heating, space cooling, and domestic hot water production which is provided to residential and commercial buildings. Air source heat pumps (ASHP) are widely used conversion technologies for providing building thermal energy...

  17. Simulated Measurements of Cooling in Muon Ionization Cooling Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mohayai, Tanaz [IIT, Chicago; Rogers, Chris [Rutherford; Snopok, Pavel [Fermilab

    2016-06-01

    Cooled muon beams set the basis for the exploration of physics of flavour at a Neutrino Factory and for multi-TeV collisions at a Muon Collider. The international Muon Ionization Cooling Experiment (MICE) measures beam emittance before and after an ionization cooling cell and aims to demonstrate emittance reduction in muon beams. In the current MICE Step IV configuration, the MICE muon beam passes through low-Z absorber material for reducing its transverse emittance through ionization energy loss. Two scintillating fiber tracking detectors, housed in spectrometer solenoid modules upstream and downstream of the absorber are used for reconstructing position and momentum of individual muons for calculating transverse emittance reduction. However, due to existence of non-linear effects in beam optics, transverse emittance growth can be observed. Therefore, it is crucial to develop algorithms that are insensitive to this apparent emittance growth. We describe a different figure of merit for measuring muon cooling which is the direct measurement of the phase space density.

  18. New Approaches to Final Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Neuffer, David [Fermilab

    2014-11-10

    A high-energy muon collider scenario require a “final cooling” system that reduces transverse emittances by a factor of ~10 while allowing longitudinal emittance increase. The baseline approach has low-energy transverse cooling within high-field solenoids, with strong longitudinal heating. This approach and its recent simulation are discussed. Alternative approaches which more explicitly include emittance exchange are also presented. Round-to-flat beam transform, transverse slicing, and longitudinal bunch coalescence are possible components of the alternative approach. A more explicit understanding of solenoidal cooling beam dynamics is introduced.

  19. Beam Dynamics With Electron Cooling

    CERN Document Server

    Uesugi, T; Noda, K; Shibuya, S; Syresin, E M

    2004-01-01

    Electron cooling experiments have been carried out at HIMAC in order to develop new technologies in heavy-ion therapy and related researches. The cool-stacking method, in particular, has been studied to increase the intensity of heavy-ions. The maximum stack intensity was 2 mA, above which a fast ion losses occurred simulatneously with the vertical coherent oscillations. The instability depends on the working point, the stacked ion-density and the electron-beam density. The instability was suppressed by reducing the peak ion-density with RF-knockout heating.

  20. Aggregating and Disaggregating Flexibility Objects

    DEFF Research Database (Denmark)

    Siksnys, Laurynas; Valsomatzis, Emmanouil; Hose, Katja

    2015-01-01

    In many scientific and commercial domains we encounter flexibility objects, i.e., objects with explicit flexibilities in a time and an amount dimension (e.g., energy or product amount). Applications of flexibility objects require novel and efficient techniques capable of handling large amounts...... energy data management and discuss strategies for aggregation and disaggregation of flex-objects while retaining flexibility. This paper further extends these approaches beyond flex-objects originating from energy consumption by additionally considering flex-objects originating from energy production...... and aiming at energy balancing during aggregation. In more detail, this paper considers the complete life cycle of flex-objects: aggregation, disaggregation, associated requirements, efficient incremental computation, and balance aggregation techniques. Extensive experiments based on real-world data from...

  1. Two-dimensional flexible nanoelectronics

    National Research Council Canada - National Science Library

    Akinwande, Deji; Petrone, Nicholas; Hone, James

    2014-01-01

    .... With the discovery of hexagonal boron nitride as an ideal dielectric, the materials are now in place to advance integrated flexible nanoelectronics, which uniquely take advantage of the unmatched...

  2. Flexible Transparent Electronic Gas Sensors.

    Science.gov (United States)

    Wang, Ting; Guo, Yunlong; Wan, Pengbo; Zhang, Han; Chen, Xiaodong; Sun, Xiaoming

    2016-07-01

    Flexible and transparent electronic gas sensors capable of real-time, sensitive, and selective analysis at room-temperature, have gained immense popularity in recent years for their potential to be integrated into various smart wearable electronics and display devices. Here, recent advances in flexible transparent sensors constructed from semiconducting oxides, carbon materials, conducting polymers, and their nanocomposites are presented. The sensing material selection, sensor device construction, and sensing mechanism of flexible transparent sensors are discussed in detail. The critical challenges and future development associated with flexible and transparent electronic gas sensors are presented. Smart wearable gas sensors are believed to have great potential in environmental monitoring and noninvasive health monitoring based on disease biomarkers in exhaled gas.

  3. Flexible sensors based on nanoparticles.

    Science.gov (United States)

    Segev-Bar, Meital; Haick, Hossam

    2013-10-22

    Flexible sensors can be envisioned as promising components for smart sensing applications, including consumer electronics, robotics, prosthetics, health care, safety equipment, environmental monitoring, homeland security and space flight. The current review presents a concise, although admittedly nonexhaustive, didactic review of some of the main concepts and approaches related to the use of nanoparticles (NPs) in flexible sensors. The review attempts to pull together different views and terminologies used in the NP-based sensors, mainly those established via electrical transduction approaches, including, but, not confined to: (i) strain-gauges, (ii) flexible multiparametric sensors, and (iii) sensors that are unaffected by mechanical deformation. For each category, the review presents and discusses the common fabrication approaches and state-of-the-art results. The advantages, weak points, and possible routes for future research, highlighting the challenges for NP-based flexible sensors, are presented and discussed as well.

  4. Flexible protection for metal bellows

    Science.gov (United States)

    Kimble, K. G.

    1970-01-01

    RTV silicone is used with a braided wire sheath surrounding the metal bellows in fluid transfer systems. It demonstrated best overall performance in flexibility and shock absorbing tests, high temperature, low temperature, and salt spray.

  5. Flexible, highly efficient all-polymer solar cells.

    Science.gov (United States)

    Kim, Taesu; Kim, Jae-Han; Kang, Tae Eui; Lee, Changyeon; Kang, Hyunbum; Shin, Minkwan; Wang, Cheng; Ma, Biwu; Jeong, Unyong; Kim, Taek-Soo; Kim, Bumjoon J

    2015-10-09

    All-polymer solar cells have shown great potential as flexible and portable power generators. These devices should offer good mechanical endurance with high power-conversion efficiency for viability in commercial applications. In this work, we develop highly efficient and mechanically robust all-polymer solar cells that are based on the PBDTTTPD polymer donor and the P(NDI2HD-T) polymer acceptor. These systems exhibit high power-conversion efficiency of 6.64%. Also, the proposed all-polymer solar cells have even better performance than the control polymer-fullerene devices with phenyl-C61-butyric acid methyl ester (PCBM) as the electron acceptor (6.12%). More importantly, our all-polymer solar cells exhibit dramatically enhanced strength and flexibility compared with polymer/PCBM devices, with 60- and 470-fold improvements in elongation at break and toughness, respectively. The superior mechanical properties of all-polymer solar cells afford greater tolerance to severe deformations than conventional polymer-fullerene solar cells, making them much better candidates for applications in flexible and portable devices.

  6. Cooling neutrons using non-dispersive magnetic excitations

    CERN Document Server

    Zimmer, Oliver

    2014-01-01

    A new method is proposed for cooling neutrons by inelastic magnetic scattering in weakly absorbing, cold paramagnetic systems. Kinetic neutron energy is removed in constant decrements determined by the Zeeman energy of paramagnetic atoms or ions in an external magnetic field, or by zero-field level splittings in magnetic molecules. Analytical solutions of the stationary neutron transport equation are given using inelastic neutron scattering cross sections derived in an appendix. They neglect any inelastic process except the paramagnetic scattering and hence still underestimate very-cold neutron densities. Molecular oxygen with its triplet ground state appears particularly promising, notably as a host in fully deuterated oxygen-clathrate hydrate, or more exotically, in dry oxygen-He4 van der Waals clusters. At a neutron temperature about 6 K, for which neutron conversion to ultra-cold neutrons by single-phonon emission in pure superfluid He4 works best, conversion rates due to paramagnetic scattering in the cl...

  7. FLEXIBLE FLATFOOT IN CHILDREN (REVIEW)

    OpenAIRE

    Владимир Маркович Кенис; Юрий Алексеевич Лапкин; Руслан Халилович Хусаинов; Андрей Викторович Сапоговский

    2014-01-01

    Flatfoot is one of the most common musculoskeletal conditions in the daily practice of pediatric orthopedists. Despite of numerous studies, diagnostic criteria and principles of management remain controversial. Flexible flatfoot - is visually detectable decrease in the height of the longitudinal arch of the foot, which can be spontaneously corrected by active or passive motion and not accompanied by any contracture of foot and ankle. Flexible flatfoot is a benign condition which is normal for...

  8. Value of Flexibility - Phase 1

    Science.gov (United States)

    2010-09-25

    flexibility could also change the calculus of how we determine when to start a new program vice modifying an existing one. Flexibility could even help...decades ago by Steward as a ‖framework for formally identifying and tracking relationships between design variables‖ [ Steward , 1981]. Keese [2007...Paper presented at the 6th Conference on Systems Engineering Research, Los Angeles, CA. Shreve, S. E. (2004). Stochastic calculus for finance. New

  9. Flexible packaging for PV modules

    Science.gov (United States)

    Dhere, Neelkanth G.

    2008-08-01

    Economic, flexible packages that provide needed level of protection to organic and some other PV cells over >25-years have not yet been developed. However, flexible packaging is essential in niche large-scale applications. Typical configuration used in flexible photovoltaic (PV) module packaging is transparent frontsheet/encapsulant/PV cells/flexible substrate. Besides flexibility of various components, the solder bonds should also be flexible and resistant to fatigue due to cyclic loading. Flexible front sheets should provide optical transparency, mechanical protection, scratch resistance, dielectric isolation, water resistance, UV stability and adhesion to encapsulant. Examples are Tefzel, Tedlar and Silicone. Dirt can get embedded in soft layers such as silicone and obscure light. Water vapor transmittance rate (WVTR) of polymer films used in the food packaging industry as moisture barriers are ~0.05 g/(m2.day) under ambient conditions. In comparison, light emitting diodes employ packaging components that have WVTR of ~10-6 g/(m2.day). WVTR of polymer sheets can be improved by coating them with dense inorganic/organic multilayers. Ethylene vinyl acetate, an amorphous copolymer used predominantly by the PV industry has very high O2 and H2O diffusivity. Quaternary carbon chains (such as acetate) in a polymer lead to cleavage and loss of adhesional strength at relatively low exposures. Reactivity of PV module components increases in presence of O2 and H2O. Adhesional strength degrades due to the breakdown of structure of polymer by reactive, free radicals formed by high-energy radiation. Free radical formation in polymers is reduced when the aromatic rings are attached at regular intervals. This paper will review flexible packaging for PV modules.

  10. Flexible solar-array mechanism

    Science.gov (United States)

    Olson, M. C.

    1972-01-01

    One of the key elements of the flexible rolled-up solar array system is a mechanism to deploy, retract, and store the flexible solar-cell arrays. The selection of components, the design of the mechanism assembly, and the tests that were performed are discussed. During 6 months in orbit, all mission objectives were satisfied, and inflight performance has shown good correlation with preflight analyses and tests.

  11. Flexible Learning Spaces Evaluation Report

    OpenAIRE

    Bullimore, A.; Reader, K.; Sultany, A

    2013-01-01

    City University, London is tackling the challenge of ensuring the learning spaces provided are able to meet the anticipated increase in technology usage and prevalent pedagogies. There is no longer a standard classroom design that will achieve this goal and therefore it is imperative to pilot and explore a variety of flexible learning spaces. This report feeds back on an\\ud evaluation of two flexible learning space approaches piloted in the autumn term of 2012 as alternatives to traditional c...

  12. Evaporative Cooling and Dehumidification Garment for Portable Life Support Systems

    Science.gov (United States)

    Izenson, Michael; Chen, Weibo; Bue, Grant

    2013-01-01

    This paper describes the design and development of an innovative thermal and humidity control system for future space suits. The system comprises an evaporation cooling and dehumidification garment (ECDG) and a lithium chloride absorber radiator (LCAR). The ECDG absorbs heat and water vapor from inside the suit pressure garment, while the LCAR rejects heat to space without venting water vapor. The ECDG is built from thin, flexible patches with coversheets made of non-porous, water-permeable membranes that -enclose arrays of vapor flow passages. Water vapor from inside the spacesuit diffuses across the water permeable membranes, enters the vapor flow channels, and then flows to the LCAR, thus dehumidifying the internal volume of the space suit pressure garment. Additional water evaporation inside the ECDG provides cooling for sensible heat loads. -The heat released from condensation and absorption in the LCAR is rejected to the environment by thermal radiation. We have assembled lightweight and flexible ECDG pouches from prototypical materials and measured their performance in a series of separate effects tests under well-controlled, prototypical conditions. Sweating hot plate tests at typical space suit pressures show that ECDG pouches can absorb over 60 W/ft of latent heat and 20 W/ft of sensible heat from the pressure garment environment. These results are in good agreement with the predictions of our analysis models.

  13. Review on Telephone Conversations Analysis

    Institute of Scientific and Technical Information of China (English)

    张咏梅

    2014-01-01

    Telephone conversation, one of the most common uses of human communication, has been a hot topic in linguistic field in modern times. This essay aims at reviewing the main theories and findings in telephone conversation analysis and provid-ing some insights of this aspect which can often be overlooked in our daily life. It is also hoped that this essay can help to pave a foundation for further in-depth study in telephone conversations.

  14. Paradoxical therapy in conversion disorder

    OpenAIRE

    ATAOĞLU, Ahmet

    2014-01-01

    Paradoxical therapy consists of suggesting that the patient intentionally engages in the unwanted behaviour, such as performing complusive ritual or bringing on a conversion attack. In this study paradoxical intention (PI) was used with to half of the patients with conversion disorders, while the other half were treated with diazepam in order to examine the efficiency of the PI versus diazepam in conversion disorder. Patients treated with PI appeared to have a greater improvement r...

  15. Developmental constraints on behavioural flexibility.

    Science.gov (United States)

    Holekamp, Kay E; Swanson, Eli M; Van Meter, Page E

    2013-05-19

    We suggest that variation in mammalian behavioural flexibility not accounted for by current socioecological models may be explained in part by developmental constraints. From our own work, we provide examples of constraints affecting variation in behavioural flexibility, not only among individuals, but also among species and higher taxonomic units. We first implicate organizational maternal effects of androgens in shaping individual differences in aggressive behaviour emitted by female spotted hyaenas throughout the lifespan. We then compare carnivores and primates with respect to their locomotor and craniofacial adaptations. We inquire whether antagonistic selection pressures on the skull might impose differential functional constraints on evolvability of skulls and brains in these two orders, thus ultimately affecting behavioural flexibility in each group. We suggest that, even when carnivores and primates would theoretically benefit from the same adaptations with respect to behavioural flexibility, carnivores may nevertheless exhibit less behavioural flexibility than primates because of constraints imposed by past adaptations in the morphology of the limbs and skull. Phylogenetic analysis consistent with this idea suggests greater evolutionary lability in relative brain size within families of primates than carnivores. Thus, consideration of developmental constraints may help elucidate variation in mammalian behavioural flexibility.

  16. Oxide Heteroepitaxy for Flexible Optoelectronics.

    Science.gov (United States)

    Bitla, Yugandhar; Chen, Ching; Lee, Hsien-Chang; Do, Thi Hien; Ma, Chun-Hao; Qui, Le Van; Huang, Chun-Wei; Wu, Wen-Wei; Chang, Li; Chiu, Po-Wen; Chu, Ying-Hao

    2016-11-30

    The emerging technological demands for flexible and transparent electronic devices have compelled researchers to look beyond the current silicon-based electronics. However, fabrication of devices on conventional flexible substrates with superior performance are constrained by the trade-off between processing temperature and device performance. Here, we propose an alternative strategy to circumvent this issue via the heteroepitaxial growth of transparent conducting oxides (TCO) on the flexible mica substrate with performance comparable to that of their rigid counterparts. With the examples of ITO and AZO as a case study, a strong emphasis is laid upon the growth of flexible yet epitaxial TCO relying muscovite's superior properties compared to those of conventional flexible substrates and its compatibility with the present fabrication methods. Besides excellent optoelectro-mechanical properties, an additional functionality of high-temperature stability, normally lacking in the current state-of-the-art transparent flexitronics, is provided by these heterostructures. These epitaxial TCO electrodes with good chemical and thermal stabilities as well as mechanical durability can significantly contribute to the field of flexible, light-weight, and portable smart electronics.

  17. A comparative study on showerhead cooling performance

    Energy Technology Data Exchange (ETDEWEB)

    Falcoz, C.; Ott, P. [Ecole Polytechnique Federale de Lausanne (EPFL), Laboratoire de Thermique Appliquee et de Turbomachines (LTT), 1015 Lausanne (Switzerland); Weigand, B. [Institut fuer Thermodynamik der Luft- und Raumfahrt (ITLR), Stuttgart University, Pfaffenwaldring 31, 70569 Stuttgart (Germany)

    2006-04-15

    In modern gas turbines, the turbine airfoil leading edge is currently protected from the hot gas by specific film cooling schemes, so called showerhead cooling. The present paper shows a numerical study of different showerhead cooling geometries. The 3D finite element program ABAQUS as well as a 2D finite element program have been employed to predict the showerhead cooling performance. In the numerical calculations, the different cooling effects and their contribution to the total showerhead cooling performance have been investigated separately. From the numerical calculations a simple method has been derived which enables the prediction of the performance of a 3D showerhead cooling scheme by simple 2D computations. Experimental investigations on showerhead cooling have been presented in a companion paper [C. Falcoz, B. Weigand, P. Ott, Experimental investigations on showerhead cooling on a blunt body. Int. J. Heat Mass Transfer, in press. r publication]. (author)

  18. Ionization Cooling for Muon Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Alexahin, Y. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Neuffer, D. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Prebys, E. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)

    2014-09-18

    Possible application for muon experiments such as mu2e is discussed of the initial part of the ionization cooling channel originally developed for muon collider. It is shown that with the FNAL Booster as the proton driver the mu2e sensitivity can be increased by two orders of magnitude compared to the presently considered experiment.

  19. Ionization Cooling for Muon Experiments

    OpenAIRE

    Alexahin, Y.; D. Neuffer; Prebys, E.

    2014-01-01

    Possible application for muon experiments such as mu2e is discussed of the initial part of the ionization cooling channel originally developed for muon collider. It is shown that with the FNAL Booster as the proton driver the mu2e sensitivity can be increased by two orders of magnitude compared to the presently considered experiment.

  20. Inductive cooling in quantum magnetomechanics

    Science.gov (United States)

    Romero-Sanchez, Erick; Twamley, Jason; Bowen, Warwick P.; Vanner, Michael R.

    Coupling to light or microwave fields allows quantum control of the motion of a mechanical oscillator, and offers prospects for precision sensing, quantum information systems, and tests of fundamental physics. In cavity electromechanics ground state cooling has been achieved using resolved sideband cooling. Here we present an alternative approach based on a magnetomechanical system that inductively couples an LC resonator to a mechanical oscillator. The experimental setup consists of a micro cantilever with a pyramidal magnetic tip attached at the end of the beam. The sharp end of the magnetic tip is positioned close to the planar microfabricated inductor of the LC resonator. The displacement in the position of the end of the cantilever generates a change in flux through the coil inducing an electromotive force in the circuit. The current in the LC resonator generates a magnetic field, and then a force between the tip and the coil. When they are strongly coupled and the mechanical resonance frequency ωm exceeds the electrical decay rate of the resonator γe, resolved sideband cooling can be used to cool the mechanics. We present estimations for the coupling rates and the experimental parameters required for these experiments. E. Romero acknowledges to CONACyT.