Composition heterogeneity analysis for DUPIC fuel(I) - Statistical analysis

Energy Technology Data Exchange (ETDEWEB)

Choi, Hang Bok [Korea Atomic Energy Research Institute, Taejon (Korea)

1999-08-01

The fuel composition heterogeneity effect on reactor performance parameters was assessed by refueling simulations for three DUPIC fuel options of fuel composition heterogeneity control: the fissile content adjustment, the reactivity control by slightly enriched and depleted uranium, and the reactivity control by natural uranium. For each DUPIC fuel option, the simulations were performed using 30 heterogeneous fuel types which were determined by the agglomerative hierarchical clustering method. The heterogeneity effect was considered during the refueling simulation by randomly selecting fuel types for the refueling operation. The refueling simulations of the heterogeneous core have shown that the key performance parameters such as the maximum channel power (MCP), maximum bundle power (MBP), and channel power peaking factor (CPPF) are close to those of the core that has single fuel type. For the three DUPIC fuel options, the uncertainties of MCP, MBP, and CPPF due to the fuel composition heterogeneity are less than 0.6, 1.5 and 0.8%, respectively, including the uncertainty of the group-average fuel property. This study has shown that the three DUPIC fuel options reduces the composition heterogeneity effectively and the zone power control system has a sufficient margin to adjust the perturbations cased by the fuel composition heterogeneity. 15 refs., 28 figs.,10 tabs. (Author)

Spent Nuclear Fuel (SNF) Project Cold Vacuum Drying (CVD) Facility Operations Manual

International Nuclear Information System (INIS)

IRWIN, J.J.

2000-01-01

The mission of the Spent Nuclear Fuel (SNF) Project Cold Vacuum Drying Facility (CVDF) is to achieve the earliest possible removal of free water from Multi-Canister Overpacks (MCOs). The MCOs contain metallic uranium SNF that have been removed from the 100K Area fuel storage water basins (i.e., the K East and K West Basins) at the US. Department of Energy Hanford Site in Southeastern Washington state. Removal of free water is necessary to halt water-induced corrosion of exposed uranium surfaces and to allow the MCOs and their SNF payloads to be safely transported to the Hanford Site 200 East Area and stored within the SNF Project Canister Storage Building (CSB). The CVDF is located within a few hundred yards of the basins, southwest of the 165KW Power Control Building and the 105KW Reactor Building. The site area required for the facility and vehicle circulation is approximately 2 acres. Access and egress is provided by the main entrance to the 100K inner area using existing roadways. The CVDF will remove free. water from the MCOs to reduce the potential for continued fuel-water corrosion reactions. The cold vacuum drying process involves the draining of bulk water from the MCO and subsequent vacuum drying. The MCO will be evacuated to a pressure of 8 torr or less and backfilled with an inert gas (helium). The MCO will be sealed, leak tested, and then transported to the CSB within a sealed shipping cask. (The MCO remains within the same shipping Cask from the time it enters the basin to receive its SNF payload until it is removed from the Cask by the CSB MCO handling machine.) The CVDF subproject acquired the required process systems, supporting equipment, and facilities. The cold vacuum drying operations result in an MCO containing dried fuel that is prepared for shipment to the CSB by the Cask transportation system. The CVDF subproject also provides equipment to dispose of solid wastes generated by the cold vacuum drying process and transfer process water removed

Surface enhanced 316L/SiC nano-composite coatings via laser cladding and following cold-swaging process

Science.gov (United States)

Li, Yuhang; Gao, Shiyou

2017-10-01

Cold-swaging is one of a cold deformation processes, and ceramic-reinforcement nano-composite coatings can effectively improve the performance of metal matrix surface. Therefore, the two processes are innovatively combined to further improve the surface properties of the metal matrix in this paper. The microstructure and surface properties of the laser cladding 316L + 10 wt% SiC nano-composite coatings were examined through designed experiments after cold-swaging by self-developed hydraulic machine. Furthermore, the coatings were compared with those without cold-swaging coatings at the same time. The result shows that the cold-swaging process can further enhance the tensile strength, micro-hardness and the wear resistance of the composite coating. This study can be used as a reference for further strengthening of laser cladding nano-composite coatings in future research.

Spent Nuclear Fuel (SNF) Project Cold Vacuum Drying (CVD) Facility Operations Manual

Energy Technology Data Exchange (ETDEWEB)

IRWIN, J.J.

2000-02-03

This document provides the Operations Manual for the Cold Vacuum Drying Facility (CVDF). The Manual was developed in conjunction with HNF-SD-SNF-SAR-002, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of the Processing Systems (Garvin 1998) and, the HNF-SD-SNF-DRD-002, 1997, Cold Vacuum Drying Facility Design Requirements, Rev. 3a. The Operations Manual contains general descriptions of all the process, safety and facility systems in the CVDF, a general CVD operations sequence, and has been developed for the spent nuclear fuel project (SNFP) Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved.

Spent Nuclear Fuel (SNF) Cold Vacuum Drying (CVD) Facility Operations Manual; FINAL

International Nuclear Information System (INIS)

IRWIN, J.J.

1999-01-01

This document provides the Operations Manual for the Cold Vacuum Drying Facility (CVDF). The Manual was developed in conjunction with HNF-553, Spent Nuclear Fuel Project Final Safety Analysis Report Annex B-Cold Vacuum Drying Facility. The HNF-SD-SNF-DRD-002, 1999, Cold Vacuum Drying Facility Design Requirements, Rev. 4, and the CVDF Final Design Report. The Operations Manual contains general descriptions of all the process, safety and facility systems in the CVDF, a general CVD operations sequence and references to the CVDF System Design Descriptions (SDDs). This manual has been developed for the SNFP Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved

Spent Nuclear Fuel (SNF) Project Cold Vacuum Drying (CVD) Facility Operations Manual

International Nuclear Information System (INIS)

IRWIN, J.J.

2000-01-01

This document provides the Operations Manual for the Cold Vacuum Drying Facility (CVDF). The Manual was developed in conjunction with HNF-SD-SNF-SAR-002, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of the Processing Systems (Garvin 1998) and, the HNF-SD-SNF-DRD-002, 1997, Cold Vacuum Drying Facility Design Requirements, Rev. 3a. The Operations Manual contains general descriptions of all the process, safety and facility systems in the CVDF, a general CVD operations sequence, and has been developed for the spent nuclear fuel project (SNFP) Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved

Finite element analysis of composite beam-to-column connection with cold-formed steel section

Science.gov (United States)

Firdaus, Muhammad; Saggaff, Anis; Tahir, Mahmood Md

2017-11-01

Cold-formed steel (CFS) sections are well known due to its lightweight and high structural performance which is very popular for building construction. Conventionally, they are used as purlins and side rails in the building envelopes of the industrial buildings. Recent research development on cold-formed steel has shown that the usage is expanded to the use in composite construction. This paper presents the modelling of the proposed composite connection of beam-to-column connection where cold-formed steel of lipped steel section is positioned back-to-back to perform as beam. Reinforcement bars is used to perform the composite action anchoring to the column and part of it is embedded into a slab. The results of the finite element and numerical analysis has showed good agreement. The results show that the proposed composite connection contributes to significant increase to the moment capacity.

Cold spray copper coatings for used fuel containers

Energy Technology Data Exchange (ETDEWEB)

Keech, P. [Nuclear Waste Management Organization, Toronto, ON (Canada); Vo, P.; Poirier, D.; Legoux, J-G [National Research Council, Boucherville QC, (Canada)

2015-07-01

Recently, the Nuclear Waste Management Organization has been developing copper coatings as a method of protecting steel used fuel containers (UFCs) from corrosion within a deep geological repository. The corrosion barrier design is based on the application of a copper coating bonded directly to the exterior surface of the UFC structural core. Copper coating technologies amendable to supply of pre-coated UFC vessel components and application to the weld zone following UFC closure within the radiological environment have been investigated. Copper cold spray has been assessed for both operations; this paper outlines the research and development to date of this technique. (author)

Fuel composition effect on cathode airflow control in fuel cell gas turbine hybrid systems

Science.gov (United States)

Zhou, Nana; Zaccaria, Valentina; Tucker, David

2018-04-01

Cathode airflow regulation is considered an effective means for thermal management in solid oxide fuel cell gas turbine (SOFC-GT) hybrid system. However, performance and controllability are observed to vary significantly with different fuel compositions. Because a complete system characterization with any possible fuel composition is not feasible, the need arises for robust controllers. The sufficiency of robust control is dictated by the effective change of operating state given the new composition used. It is possible that controller response could become unstable without a change in the gains from one state to the other. In this paper, cathode airflow transients are analyzed in a SOFC-GT system using syngas as fuel composition, comparing with previous work which used humidified hydrogen. Transfer functions are developed to map the relationship between the airflow bypass and several key variables. The impact of fuel composition on system control is quantified by evaluating the difference between gains and poles in transfer functions. Significant variations in the gains and the poles, more than 20% in most cases, are found in turbine rotational speed and cathode airflow. The results of this work provide a guideline for the development of future control strategies to face fuel composition changes.

EXPERIMENTAL SENSOR OF THE BENZOETHANOL COMPOSITION FOR ENGINE FUEL SYSTEM

Directory of Open Access Journals (Sweden)

V. Bgantsev

2017-12-01

Full Text Available An important aspect of the economy of internal combustion engine on benzoethanol is the accuracy of regulation of the fuel-air mixture composition. This task is complicated by fluctuations in the composition of benzoethanol, depending on the refueling of the vehicle at various filling stations. In this connection, there is a need to control the composition of benzoethanol in the fuel system of the engine and adjust the fuel supply system. With this purpose, fuel systems are equipped with special sensors that generate a signal, depending on the alcohol content of the mixed fuel. In the article one of the design solutions of the experimental sensor of the benzoethanol composition and the results of its testing with fuels of various composition are given.

Isotopic composition of fission gases in LWR fuel

International Nuclear Information System (INIS)

Jonsson, T.

2000-01-01

Many fuel rods from power reactors and test reactors have been punctured during past years for determination of fission gas release. In many cases the released gas was also analysed by mass spectrometry. The isotopic composition shows systematic variations between different rods, which are much larger than the uncertainties in the analysis. This paper discusses some possibilities and problems with use of the isotopic composition to decide from which part of the fuel the gas was released. In high burnup fuel from thermal reactors loaded with uranium fuel a significant part of the fissions occur in plutonium isotopes. The ratio Xe/Kr generated in the fuel is strongly dependent on the fissioning species. In addition, the isotopic composition of Kr and Xe shows a well detectable difference between fissions in different fissile nuclides. (author)

Improved Retrieval Technique of pin-wise composition for spent fuel recycling

Energy Technology Data Exchange (ETDEWEB)

Park, YunSeo; Kim, Myung Hyun [Kyung Hee University , Yongin (Korea, Republic of)

2016-10-15

New reutilization method which does not require fabrication processing was suggested and showed feasibility by Dr. Aung Tharn Daing. This new reutilization method is predict spent nuclear fuel pin composition, reconstruct new fuel assembly by spent nuclear pin, and directly reutilize in same PWR core. There are some limitation to predict spent nuclear fuel pin composition on his methodology such as spatial effect was not considered enough. This research suggests improving Dr. Aung Tharn Daing's retrieval technique of pin-wise composition. This new method classify fuel pin groups by its location effect in fuel assembly. Most of fuel pin composition along to burnup in fuel assembly is not highly dependent on location. However, compositions of few fuel pins where near water hole and corner of fuel assembly are quite different in same burnup. Required number of nuclide table is slightly increased from 3 to 6 for one fuel assembly with this new method. Despite of this little change, prediction of the pin-wise composition became more accurate. This new method guarantees two advantages than previous retrieving technique. First, accurate pin-wise isotope prediction is possible by considering location effect in a fuel assembly. Second, it requires much less nuclide tables than using full single assembly database. Retrieving technique of pin-wise composition can be applied on spent fuel management field useful. This technique can be used on direct use of spent fuel such as Dr. Aung Tharn Daing showed or applied on pin-wise waste management instead of conventional assembly-wise waste management.

First stage of bio-jet fuel production: non-food sunflower oil extraction using cold press method

Directory of Open Access Journals (Sweden)

Xianhui Zhao

2014-06-01

Full Text Available As a result of concerning petroleum price increasing and environmental impact, more attention is attracted to renewable resources for transportation fuels. Because not conflict with human and animal food resources, non-food vegetable oils are promising sources for developing bio-jet fuels. Extracting vegetable oil from oilseeds is the first critical step in the pathway of bio-jet fuel production. When sunflower seeds are de-hulled, there are always about 5%–15% broken seed kernels (fine meat particles left over as residual wastes with oil content up to 48%. However, the oil extracted from these sunflower seed residues is non-edible due to its quality not meeting food standards. Genetically modified sunflower grown on margin lands has been identified one of sustainable biofuel sources since it doesn't compete to arable land uses. Sunflower oils extraction from non-food sunflower seeds, sunflower meats, and fine sunflower meats (seed de-hulling residue was carried out using a cold press method in this study. Characterization of the sunflower oils produced was performed. The effect of cold press rotary frequency on oil recovery and quality was discussed. The results show that higher oil recovery was obtained at lower rotary frequencies. The highest oil recovery for sunflower seeds, sunflower meats, and fine sunflower meats in the tests were 75.67%, 89.74% and 83.19% respectively. The cold press operating conditions had minor influence on the sunflower oil quality. Sunflower meat oils produced at 15 Hz were preliminarily upgraded and distilled. The properties of the upgraded sunflower oils were improved. Though further study is needed for the improvement of processing cost and oil recovery, cold press has shown promising to extract oil from non-food sunflower seeds for future bio-jet fuel production.

Composition and methods for improved fuel production

Science.gov (United States)

Steele, Philip H.; Tanneru, Sathishkumar; Gajjela, Sanjeev K.

2015-12-29

Certain embodiments of the present invention are configured to produce boiler and transportation fuels. A first phase of the method may include oxidation and/or hyper-acidification of bio-oil to produce an intermediate product. A second phase of the method may include catalytic deoxygenation, esterification, or olefination/esterification of the intermediate product under pressurized syngas. The composition of the resulting product--e.g., a boiler fuel--produced by these methods may be used directly or further upgraded to a transportation fuel. Certain embodiments of the present invention also include catalytic compositions configured for use in the method embodiments.

Cold storage condensation heat recovery system with a novel composite phase change material

International Nuclear Information System (INIS)

Xia, Mingzhu; Yuan, Yanping; Zhao, Xudong; Cao, Xiaoling; Tang, Zhonghua

2016-01-01

Highlights: • Cold storage condensation heat recovery system using PCM was proposed. • CW with a phase change temperature of nearly 80 °C was selected as the potential PCM. • The optimal mass ratio between the CW and EG was 10:1. • The thermal and physical performances of the CW/EG were investigated. • The thermal reliability was demonstrated by 1000 cycles. - Abstract: Using condensation heat from cold storage refrigeration systems to provide heat for domestic hot water preparation and industrial hot water supply promotes energy conservation. However, few studies have investigated cold storage condensation heat recovery using phase change materials (PCMs). In this study, a cold storage condensation heat recovery system that uses PCMs has been designed and analysed. According to the principle of energy cascade recycling, different operation modes could be effectively switched to recycle condensation heat. Furthermore, a novel and suitable phase change composite material is developed for cold storage condensation heat recovery, which has a relatively large latent heat, high thermal conductivity, and an appropriate phase change temperature (i.e. 80 °C). With carnauba wax (CW) as the PCM and expanded graphite (EG) as the additive, a composite was developed with an optimal mass ratio of CW:EG = 10:1. The thermal and physical properties and the interior structure of the composite were then investigated using a scanning electron microscope (SEM), thermal constants analyser (Hot Disk), differential scanning calorimeter (DSC), and Fourier transform infrared spectrometer (FT-IR). Furthermore, experiments on the melting and solidification processes and accelerated thermal cycling were also conducted. It was found that at the optimal mass ratio of 10:1, the temperatures of the CW/EG composite in the melting and solidification processes were 81.98 °C and 80.43 °C, respectively, while the corresponding latent heats were 150.9 J/g and 142.6 J/g, respectively

Computer Simulations of Composite Electrodes in Solid-Oxide Fuel-Cells

Energy Technology Data Exchange (ETDEWEB)

Sunde, Svein

1999-07-01

Fuel cells are devices for converting the combined chemical (free) energy of fuels and oxygen (air) directly to electrical energy without relying on the dynamic action of steam heated by reacting fuel-oxygen mixtures, like in steam turbines, or of the reacting gas mixtures themselves, like in gas turbines. The basic rationale for fuel cells is their high efficiencies as compared to indirect-conversion methods. Fuel cells are currently being considered for a number of applications, among them de-centralised power supply. Fuel cells come in five basic types and are usually classified according to the type of electrolyte used, which in turn to a significant degree limits the options for anode and cathode materials. The solid-oxide fuel-cell (SOFC) , with which this thesis is concerned, is thus named after its oxide electrolyte, typically the oxide-ion conducting material yttria-stabilised zirconia (YSZ). While the cathode of an SOFC is often uniform in chemical composition (or at least intended to be), various problems of delamination, cracking etc. associated with the use of metallic anode electrocatalysts led to the development of composite SOFC anodes. Porous anodes consisting of Ni and YSZ particles in roughly 50/50 wt-% mixtures are now almost standard with any SOFC-development programme. The designer of composite SOFC electrodes is faced with at least three, interrelated questions: (1) What will be the optimum microstructure and composition of the composite electrode? (2) If the structure changes during operation, as is often observed, what will be the consequences for the internal losses in the cell? (3) How do we interpret electrochemical and conductivity measurements with regard to structure and composition? It is the primary purpose of this thesis to provide a framework for modelling the electrochemical and transport properties of composite electrodes for SOFC, and to arrive at some new insights that cannot be offered by experiment alone. Emphasis is put on

Hot Surface Ignition of A Composite Fuel Droplet

Directory of Open Access Journals (Sweden)

Glushkov Dmitrii O.

2015-01-01

Full Text Available The present study examines the characteristics of conductive heating (up to ignition temperature of a composite fuel droplet based on coal, liquid petroleum products, and water. In this paper, we have established the difference between heat transfer from a heat source to a fuel droplet in case of conductive (hot surface and convective (hot gas heat supply. The Leidenfrost effect influences on heat transfer characteristics significantly due to the gas gap between a composite fuel droplet and a hot surface.

Use of a perfume composition as a fuel for internal combustion engines

NARCIS (Netherlands)

2013-01-01

The present invention relates to fuel compositions containing perfume fractions, that is to say compositions of fragrance materials, and to the use of such perfume fractions containing fuel compositions to provide a fuel for internal combustion engines and burners. According to the present fuel

Tackling cold housing and fuel poverty in New Zealand: A review of policies, research, and health impacts

International Nuclear Information System (INIS)

Howden-Chapman, Philippa; Viggers, Helen; Chapman, Ralph; O’Sullivan, Kimberley; Telfar Barnard, Lucy; Lloyd, Bob

2012-01-01

About a quarter of New Zealand households are estimated to be in fuel poverty. NZ has a poor history of housing regulation, so existing houses are often poorly insulated and rental properties are not required to have insulation or heating. Average indoor temperatures are cold by international standards and occupants regularly report they are cold, because they cannot afford to heat their houses. Fuel poverty is thought to be a factor in NZ's high rate of excess winter mortality (16%, about 1600 deaths a year) and excess winter hospitalisations (8%). We examined the link between indoor cold and health in two community trials, the Housing, Insulation, and Health Study and the Housing, Heating, and Health Study and both interventions demonstrated encouraging benefit/cost ratios. NZ governments have translated this and other research into major policy programmes designed to retrofit insulation and efficient heating into existing houses. However, houses are predominantly electrical resistance heated and a largely unregulated electricity market has seen rapidly rising residential electricity prices. These rising energy prices, combined with low rates of economic growth, rising unemployment and generally rising income inequality, are likely to further increase levels of fuel poverty in NZ, unless broader policy action is taken. - Highlights: ► Fuel poverty of New Zealand households is rising with electricity prices. ► Average indoor housing temperatures are low by international standards. ► Excess winter mortality and hospitalisation remain relatively high. ► Trials of retrofitted insulating and heating have influenced policy programmes. ► Fuel poverty benefits of programmes could be overshadowed by rising energy prices.

Fabrication of TiNi/CFRP smart composite using cold drawn TiNi wires

Science.gov (United States)

Xu, Ya; Otsuka, Kazuhiro; Toyama, Nobuyuki; Yoshida, Hitoshi; Jang, Byung-Koog; Nagai, Hideki; Oishi, Ryutaro; Kishi, Teruo

2002-07-01

In recent years, pre-strained TiNi shape memory alloys (SMA) have been used for fabricating smart structure with carbon fibers reinforced plastics (CFRP) in order to suppress microscopic mechanical damages. However, since the cure temperature of CFRP is higher than the reverse transformation temperatures of TiNi SMA, special fixture jigs have to be used for keeping the pre-strain during fabrication, which restricted its practical application. In order to overcome this difficulty, we developed a new method to fabricate SMA/CFRP smart composites without using special fixture jigs by controlling the transformation temperatures of SMA during fabrication. This method consists of using heavily cold-worked wires to increase the reverse transformation temperatures, and of using flash electrical heating of the wires after fabrication in order to decrease the reverse transformation temperatures to a lower temperature range again without damaging the epoxy resin around SMA wires. By choosing proper cold-working rate and composition of TiNi alloys, the reverse transformation temperatures were well controlled, and the TiNi/CFRP hybrid smart composite was fabricated without using special fixture jigs. The damage suppressing effect of cold drawn wires embedded in CFRP was confirmed.

Determination of equilibrium fuel composition for fast reactor in closed fuel cycle

Directory of Open Access Journals (Sweden)

Ternovykha Mikhail

2017-01-01

Full Text Available Technique of evaluation of multiplying and reactivity characteristics of fast reactor operating in the mode of multiple refueling is presented. We describe the calculation model of the vertical section of the reactor. Calculation validations of the possibility of correct application of methods and models are given. Results on the isotopic composition, mass feed, and changes in the reactivity of the reactor in closed fuel cycle are obtained. Recommendations for choosing perspective fuel compositions for further research are proposed.

Experimental and numerical investigation of form-stable dodecane/hydrophobic fumed silica composite phase change materials for cold energy storage

International Nuclear Information System (INIS)

Chen, Jiajie; Ling, Ziye; Fang, Xiaoming; Zhang, Zhengguo

2015-01-01

Highlights: • Form-stable dodecane/fumed silica composite for cold storage is prepared. • A suggesting hypothesis that explains infiltration mechanism is proposed. • The performance of the composite phase change material is investigated. • Numerical simulation of system is carried out and results fit well. - Abstract: A kind of form-stable composite phase change materials used for cold thermal energy storage is prepared by absorbing dodecane into the hydrophobic fumed silica. With relatively suitable pore diameter and hydrophobic groups, hydrophobic fumed silica is beneficial to the penetration and infiltration of dodecane and the leakage problem solving. Scanned by electron micrographs and Fourier transformation infrared, the composite phase change material is characterized to be just physical penetration. Besides, the differential scanning calorimeter and thermo gravimetric analysis reveals the high enthalpy, good thermal stability and cycling performance of this composite phase change material. What’s more, Hot-Disk thermal constants analyzer demonstrates that the composite phase change material has low thermal conductivity which is desired in cold storage application. In the experiment, a cold energy storage system is set up and the results from the experiment show that the system has excellent performance of cold storage by incorporating composite phase change material. Apart from that, the experimental data is found to have a great agreement with the numerical simulation which is carried out by using the commercial computational fluid dynamics software FLUENT.

Process control of an HTGR fuel reprocessing cold pilot plant

International Nuclear Information System (INIS)

Rode, J.S.

1976-10-01

Development of engineering-scale systems for a large-scale HTGR fuel reprocessing demonstration facility is currently underway in a cold pilot plant. These systems include two fluidized-bed burners, which remove the graphite (carbon) matrix from the crushed HTGR fuel by high temperature (900 0 C) oxidation. The burners are controlled by a digital process controller with an all analog input/output interface which has been in use since March, 1976. The advantages of such a control system to a pilot plant operation can be summarized as follows: (1) Control loop functions and configurations can be changed easily; (2) control constants, alarm limits, output limits, and scaling constants can be changed easily; (3) calculation of data and/or interface with a computerized information retrieval system during operation are available; (4) diagnosis of process control problems is facilitated; and (5) control panel/room space is saved

Cold homes, fuel poverty and energy efficiency improvements: A longitudinal focus group approach.

Science.gov (United States)

Grey, Charlotte N B; Schmieder-Gaite, Tina; Jiang, Shiyu; Nascimento, Christina; Poortinga, Wouter

2017-08-01

Cold homes and fuel poverty have been identified as factors in health and social inequalities that could be alleviated through energy efficiency interventions. Research on fuel poverty and the health impacts of affordable warmth initiatives have to date primarily been conducted using quantitative and statistical methods, limiting the way how fuel poverty is understood. This study took a longitudinal focus group approach that allowed exploration of lived experiences of fuel poverty before and after an energy efficiency intervention. Focus group discussions were held with residents from three low-income communities before (n = 28) and after (n = 22) they received energy efficiency measures funded through a government-led scheme. The results show that improving the energy efficiency of homes at risk of fuel poverty has a profound impact on wellbeing and quality of life, financial stress, thermal comfort, social interactions and indoor space use. However, the process of receiving the intervention was experienced by some as stressful. There is a need for better community engagement and communication to improve the benefits delivered by fuel poverty programmes, as well as further qualitative exploration to better understand the wider impacts of fuel poverty and policy-led intervention schemes.

Comparison of DUPIC fuel composition heterogeneity control methods

Energy Technology Data Exchange (ETDEWEB)

Choi, Hang Bok; Ko, Won Il [Korea Atomic Energy Research Institute, Taejon (Korea)

1999-08-01

A method to reduce the fuel composition heterogeneity effect on the core performance parameters has been studied for the DUPIC fuel which is made of spent pressurized water reactor (PWR) fuels by a dry refabrication process. This study focuses on the reactivity control method which uses either slightly enriched, depleted, or natural uranium to minimize the cost rise effect on the manufacturing of DUPIC fuel, when adjusting the excess reactivity of the spent PWR fuel. In order to reduce the variation of isotopic composition of the DUPIC fuel, the inter-assembly mixing operation was taken three times. Then, three options have been considered: reactivity control by slightly enriched and depleted uranium, reactivity control by natural uranium for high reactivity spent PWR fuels, and reactivity control by natural uranium for linear reactivity spent PWR fuels. The results of this study have shown that the reactivity of DUPIC fuel can be tightly controlled with the minimum amount of fresh uranium feed. For the reactivity control by slightly enriched and depleted uranium, all the spent PWR fuels can be utilized as the DUPIC fuel and the fraction of fresh uranium feed is 3.4% on an average. For the reactivity control by natural uranium, about 88% of spent PWR fuel can be utilized as the DUPIC fuel when the linear reactivity spent PWR fuels are used, and the amount of natural uranium feed needed to control the DUPIC fuel reactivity is negligible. 13 refs., 6 figs., 16 tabs. (Author)

A Compact Safe Cold-Start (CS2) System for Scramjets using Dilute Triethylaluminum Fuel Mixtures, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — This proposal addresses the cold-start requirements of scramjet engines by developing a safe, energy-dense, and low volume hydrocarbon fuel conditioning system based...

Prediction on flexural strength of encased composite beam with cold-formed steel section

Science.gov (United States)

Khadavi, Tahir, M. M.

2017-11-01

A flexural strength of composite beam designed as boxed shaped section comprised of lipped C-channel of cold-formed steel (CFS) facing each other with reinforcement bars is proposed in this paper. The boxed shaped is kept restrained in position by a profiled metal decking installed on top of the beam to form a slab system. This profiled decking slab is cast by using self-compacting concrete where the concrete is in compression when load is applied to the beam. Reinforcement bars are used as shear connector between slab and CFS as beam. A numerical analysis method proposed by EC4 is used to predict the flexural strength of the proposed composite beam. It was assumed that elasto-plastic behaviour is developed in the cross -sectional of the proposed beam. The calculated predicted flexural strength of the proposed beam shows reasonable flexural strength for cold-formed composite beam.

Thermal Analysis of Cold Vacuum Drying (CVD) of Spent Nuclear Fuel (SNF)

International Nuclear Information System (INIS)

PIEPHO, M.G.

2000-01-01

The thermal analysis examined transient thermal and chemical behavior of the Multi-Canister Overpack (MCO) container for a broad range of cases that represent the Cold Vacuum Drying (CVD) processes. The cases were defined to consider both normal and off-normal operations at the CVD Facility for an MCO with N Reactor spent fuel. This analysis provides the basis for the MCO thermal behavior at the CVD Facility in support of the safety basis documentation

Chemical analyses and calculation of isotopic compositions of high-burnup UO{sub 2} fuels and MOX fuels

Energy Technology Data Exchange (ETDEWEB)

Matsumura, Tetsuo; Sasahara, Akihiro [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

2001-08-01

Chemical analysis activities of isotopic compositions of high-burnup UO{sub 2} fuels and MOX fuels in CRIEPI and calculation evaluation are reviewed briefly. C/E values of ORIGEN2, in which original libraries and JENDL-3.2 libraries are used, and other codes with chemical analysis data are reviewed and evaluated. Isotopic compositions of main U and Pu in fuels can be evaluated within 10% relative errors by suitable libraries and codes. Void ratio is effective parameter for C/E values in BWR fuels. JENDL-3.2 library shows remarkable improvement compared with original libraries in isotopic composition evaluations of FP nuclides. (author)

Effect of Cold Forging on Microstructure and MechanicalProperties of Al/SiC Composites

Science.gov (United States)

Hanamantraygouda, M. B.; Shivakumar, B. P., Dr; Siddappa, P. N.; Sampathkumar, L.; Prashanth, L.

2018-02-01

The objective of this work was to investigate the effect of cold forging on mechanical properties and microstructural study of Al MMCs, at different wt% of SiC and forging cycle. The Al-SiC composite material was fabricated by stir casting method at different weight percentage of SiC such as 2.5, 5, 7.5 and 10%. Further, the deformation characteristics during open-die forging of Al-SiC composite at cold conditions was investigated. Cast and forged composite material was subjected to hardness test, tensile test and impact test. The grain size, microstructure behaviour was investigated using optical microscope. The results show that hardness and strength of Al-SiC composite increases and ductility decreases as compared to Al alloy in both as-cast and forged conditions. Optical microscope images showed that the distribution of SiC in Al matrix was more homogeneous in a forged composite as compared to cast one and reduction of porosity was found. Further, it showed that due to forging cycle the grain size was reduced by 30% to 35% from initial size.

Fuel wood consumption pattern of tribal communities in cold desert of the Lahaul valley, North-Western Himalaya, India

Energy Technology Data Exchange (ETDEWEB)

Rawat, Yashwant S.; Vishvakarma, Subhash C.R. [G.B. Pant Institute of Himalayan Environment and Development, Kosi-Katarmal, 263 643 Almora, Uttarakhand (India); Todaria, N.P. [Department of Forestry, Post Box No.-59, H.N.B. Garhwal University, Srinagar, Garhwal 246 174, Uttarakhand (India)

2009-11-15

Fuel wood is the primary source of energy in rural areas of the Himalaya. Lack of resources, extremely low temperature and xeric climatic conditions of the study region (Khoksar - 3200 m, Jahlma - 3000 m, Hinsa - 2700 m and Kuthar - 2600 m) of cold desert of the Lahaul valley has led to serious deforestation due to excessive use of fuel wood in the past. On the basis of family sizes, fuel wood consumption was recorded less in large family as compared to small family. The fuel wood is used for various activities such as cooking, water heating, room heating, lighting and livestock rearing, etc. Fuel wood consumption was highest in high altitude villages as compared to low altitude villages irrespective of family size. Fuel wood consumption of 4.32 {+-} 0.99 kg/capita/day was highest at Khoksar for small family during winter season followed by the autumn (2.25 {+-} 0.15 kg/capita/day) and summer (1.38 {+-} 0.13 kg/capita/day). The labour energy expenditure for fuel wood collection was also highest for Khoksar (91.91 MJ/capita/year), followed by Hinsa (61.29 MJ/capita/year), Kuthar (52.01 MJ/capita/year) and Jahlma (51.89 MJ/capita/year), respectively. It was found that fuel wood consumption in the study region was influenced by the local cold climate and season of the year. The present information on fuel wood consumption pattern at different altitudes would be helpful in designing appropriate technologies to develop energy plantations in the region. (author)

Gas Composition Transients in the Cold Vacuum Drying (CVD) Facility

International Nuclear Information System (INIS)

PACKER, M.J.

2000-01-01

The purpose of this document is to evaluate selected problems involving the prediction of transient gas compositions during Cold Vacuum Drying operations. The problems were evaluated to answer specific design questions. The document is formatted as a topical report with each section representing a specific problem solution. The problem solutions are reported in the calculation format specified in HNF-1613, Rev. 0, EP 7.6

Spent reactor fuel benchmark composition data for code validation

International Nuclear Information System (INIS)

Bierman, S.R.

1991-09-01

To establish criticality safety margins utilizing burnup credit in the storage and transport of spent reactor fuels requires a knowledge of the uncertainty in the calculated fuel composition used in making the reactivity assessment. To provide data for validating such calculated burnup fuel compositions, radiochemical assays are being obtained as part of the United States Department of Energy From-Reactor Cask Development Program. Destructive assay data are being obtained from representative reactor fuels having experienced irradiation exposures up to about 55 GWD/MTM. Assay results and associated operating histories on the initial three samples analyzed in this effort are presented. The three samples were taken from different axial regions of the same fuel rod and represent radiation exposures of about 27, 37, and 44 GWD/MTM. The data are presented in a benchmark type format to facilitate identification/referencing and computer code input

Emission of pollutants from the combustion of composite fuels by metallurgical processes

Directory of Open Access Journals (Sweden)

J. Łabaj

2015-10-01

Full Text Available This paper presents the results of the study on emission characteristics of pollutants resulting from combustion process of composite alternative fuels for use in the processes of pyrometallurgy of copper as an alternative fuel to currently used coke breeze. These fuels are mainly based on waste carrier of “C” element, and the composition of the fuel is modelled in order to obtain the appropriate energy and emission parameters as well as strength parameters. These studies confirmed the possibility of using composite fuels as an alternative reducing agent as well as an energy carrier in the processes of pyrometallurgy of copper.

Beneficial effects of laser irradiation on the deposition process of diamond/Ni60 composite coating with cold spray

Energy Technology Data Exchange (ETDEWEB)

Yao, Jianhua, E-mail: laser@zjut.edu.cn; Yang, Lijing; Li, Bo; Li, Zhihong

2015-03-01

Graphical abstract: - Highlights: • The hard Ni-based alloy powder as matrix in diamond composite coating was studied. • The influence of laser on diamond distribution of composite coating was analyzed. • The graphitization of diamond was prohibited in supersonic laser deposition process. • The abrasion mechanisms of diamond/Ni60 composite coating were discussed. - Abstract: Although cold spray process has many unique advantages over other coating techniques, it has difficulties in depositing hard materials. This article presents a study in the beneficial effects of laser irradiation on the fabrication process of diamond/Ni60 composite coating using cold spray. The focus of this research is on the comparison between the composite coatings produced with laser cladding (LC) and with supersonic laser deposition (SLD), with respect to diamond graphitization and tribological properties, thus to demonstrate the beneficial effects of laser irradiation on the cold spray process. The influence of deposition temperature on the coating characteristics, such as deposition efficiency, diamond volume fraction, microstructure and phase is also investigated. The tribological properties of the diamond/Ni60 composite coating produced with SLD are determined using a pin-on-disc tribometer, along with the diamond/Ni60 coating produced using LC with the optimal process parameters for comparison. The experimental results show that with the assistance of laser irradiation, diamond/Ni60 composite coating can be successfully deposited using cold spray; the obtained coating is superior to that processed with LC, because SLD can suppress the graphitization of the diamond particles. The diamond/Ni60 composite coating fabricated with SLD has much better tribological properties than the LC coating.

Cold spray deposition of Ti{sub 2}AlC coatings for improved nuclear fuel cladding

Energy Technology Data Exchange (ETDEWEB)

Maier, Benjamin R. [University of Wisconsin, Madison, WI (United States); Garcia-Diaz, Brenda L. [Savannah River National Laboratory, Aiken, SC (United States); Hauch, Benjamin [University of Wisconsin, Madison, WI (United States); Olson, Luke C.; Sindelar, Robert L. [Savannah River National Laboratory, Aiken, SC (United States); Sridharan, Kumar, E-mail: kumar@engr.wisc.edu [University of Wisconsin, Madison, WI (United States)

2015-11-15

Coatings of Ti{sub 2}AlC MAX phase compound have been successfully deposited on Zircaloy-4 (Zry-4) test flats, with the goal of enhancing the accident tolerance of LWR fuel cladding. Low temperature powder spray process, also known as cold spray, has been used to deposit coatings ∼90 μm in thickness using powder particles of <20 μm. X-ray diffraction analysis showed the phase-content of the deposited coatings to be identical to the powders indicating that no phase transformation or oxidation had occurred during the coating deposition process. The coating exhibited a high hardness of about 800 H{sub K} and pin-on-disk wear tests using abrasive ruby ball counter-surface showed the wear resistance of the coating to be significantly superior to the Zry-4 substrate. Scratch tests revealed the coatings to be well-adhered to the Zry-4 substrate. Such mechanical integrity is required for claddings from the standpoint of fretting wear resistance and resisting wear handling and insertion. Air oxidation tests at 700 °C and simulated LOCA tests at 1005 °C in steam environment showed the coatings to be significantly more oxidation resistant compared to Zry-4 suggesting that such coatings can potentially provide accident tolerance to nuclear fuel cladding. - Highlights: • Deposited Ti{sub 2}AlC coatings on Zircaloy-4 substrates with a low pressure powder spray process, also known as cold spray. • Coatings have high hardness and wear resistance for both damage resistance during rod insertion and fretting wear resistance. • The oxidation resistance of Ti{sub 2}AlC coated Zircaloy-4 at 700 °C and 1005 °C was significantly superior to uncoated Zircaloy. • Cold spray of Ti{sub 2}AlC demonstrates considerable promise as a near-term solution for accident tolerant Zr-alloy fuel claddings.

Correlations among FBR core characteristics for various fuel compositions

International Nuclear Information System (INIS)

Maruyama, Shuhei; Ohki, Shigeo; Okubo, Tsutomu; Kawashima, Katsuyuki; Mizuno, Tomoyasu

2012-01-01

In the design of a fast breeder reactor (FBR) core for the light water reactor (LWR) to FBR transition stage, it is indispensable to grasp the effect of a wide range of fuel composition variations on the core characteristics. This study finds good correlations between burnup reactivity and safety parameters, such as the sodium void reactivity and Doppler coefficient, for various fuel compositions and determines the mechanisms behind these correlations with the aid of sensitivity analyses. It is clarified that the Doppler coefficient is actually correlated with the other core characteristics by considering the constraint imposed by the requirement of sustaining criticality on the fuel composition variations. These correlations make it easy to specify the various properties ranges for core reactivity control and core safety, which are important for core design in determining the core specifications and performance. They provide significant information for FBR core design for the transition stage. Moreover, as an application of the above-mentioned correlations, a simplified burnup reactivity index is developed for rapid and rational estimation of the core characteristic variations. With the use of this index and these correlations, the core characteristic variations can be estimated for various fuel compositions without repeating the core calculations. (author)

Fructan metabolism and changes in fructan composition during cold acclimation in perennial ryegrass

DEFF Research Database (Denmark)

Abeynayake, Shamila; Etzerodt, Thomas; Jonavičienė, Kristina

2015-01-01

. The ecotype ‘Falster’, adapted to cold climates, increased total fructan content and produced more fructans (DP˃7) in the roots than the variety ‘Veyo’, adapted to warmer climates suggesting that accumulation of fructans in roots, especially the high-DP fructans as an adaptive trait for plant recovery after......Perennial ryegrass (Lolium perenne L.) produces high levels of fructans as a mixture of oligomers with different degrees of polymerization (DP). The present study describes the analysis of the compositional changes in the full spectrum of fructan oligomers, fructan distribution between above ground...... biomass (top) and the roots, and the transcription of candidate genes involved in fructan metabolism during cold acclimation in perennial ryegrass variety ‘Veyo’ and ecotype ‘Falster’ from distinct geographical origins. We observed changes in fructan composition and induction of low-DP fructans...

Effects of variations in fuel pellet composition and size on mixed-oxide fuel pin performance

International Nuclear Information System (INIS)

Makenas, B.J.; Jensen, B.W.; Baker, R.B.

1980-10-01

Experiments have been conducted which assess the effects on fuel pin performance of specific minor variations from nominal in both fuel pellet size and pellet composition. Such pellets are generally referred to in the literature as rogue pellets. The effect of these rogue pellets on fuel pin and reactor performance is shown to be minimal

Cold-Sprayed AZ91D Coating and SiC/AZ91D Composite Coatings

Directory of Open Access Journals (Sweden)

Yingying Wang

2018-03-01

Full Text Available As an emerging coating building technique, cold spraying has many advantages to elaborate Mg alloy workpieces. In this study, AZ91D coatings and AZ91D-based composite coatings were deposited using cold spraying. Coatings were prepared using different gas temperatures to obtain the available main gas temperature. Compressed air was used as the accelerating gas, and although magnesium alloy is oxidation-sensitive, AZ91D coatings with good performance were obtained. The results show that dense coatings can be fabricated until the gas temperature is higher than 500 °C. The deposition efficiency increases greatly with the gas temperature, but it is lower than 10% for all coating specimens. To analyze the effects of compressed air on AZ91D powder particles and the effects of gas temperature on coatings, the phase composition, porosity, cross-sectional microstructure, and microhardness of coatings were characterized. X-ray diffraction and oxygen content analysis clarified that no phase transformation or oxidation occurred on AZ91D powder particles during cold spraying processes with compressed air. The porosity of AZ91D coatings remained between 3.6% and 3.9%. Impact melting was found on deformed AZ91D particles when the gas temperature increased to 550 °C. As-sprayed coatings exhibit much higher microhardness than as-casted bulk magnesium, demonstrating the dense structure of cold-sprayed coatings. To study the effects of ceramic particles on cold-sprayed AZ91D coatings, 15 vol % SiC powder particles were added into the feedstock powder. Lower SiC content in the coating than in the feedstock powder means that the deposition efficiency of the SiC powder particles is lower than the deposition efficiency of AZ91D particles. The addition of SiC particles reduces the porosity and increases the microhardness of cold-sprayed AZ91D coatings. The corrosion behavior of AZ91D coating and SiC reinforced AZ91D composite coating were examined. The Si

Compositional Effects of Gasoline Fuels on Combustion, Performance and Emissions in Engine

KAUST Repository

Ahmed, Ahfaz

2016-10-17

Commercial gasoline fuels are complex mixtures of numerous hydrocarbons. Their composition differs significantly owing to several factors, source of crude oil being one of them. Because of such inconsistency in composition, there are multiple gasoline fuel compositions with similar octane ratings. It is of interest to comparatively study such fuels with similar octane ratings and different composition, and thus dissimilar physical and chemical properties. Such an investigation is required to interpret differences in combustion behavior of gasoline fuels that show similar knock characteristics in a cooperative fuel research (CFR) engine, but may behave differently in direct injection spark ignition (DISI) engines or any other engine combustion modes. Two FACE (Fuels for Advanced Combustion Engines) gasolines, FACE F and FACE G with similar Research and Motor Octane Numbers but dissimilar physical properties were studied in a DISI engine under two sets of experimental conditions; the first set involved early fuel injection to allow sufficient time for fuel-air mixing hence permitting operation similar to homogenous DISI engines, while the second set consists of advance of spark timings to attain MBT (maximum brake torque) settings. These experimental conditions are repeated across different load points to observe the effect of increasing temperature and pressure on combustion and emission parameters. The differences in various engine-out parameters are discussed and interpreted in terms of physical and thermodynamic properties of the fuels.

Cool? Young people investigate living in cold housing and fuel poverty. A mixed methods action research study

Directory of Open Access Journals (Sweden)

Kimberley C. O'Sullivan

2017-12-01

Conclusion: The integrated results confirm that cold housing and risk of fuel poverty are important problems for young people in New Zealand. Results contribute to the evidence-base for policy targeting of schemes such as the Government-sponsored retrofitting of insulation to households with dependent children.

Direct write of copper-graphene composite using micro-cold spray

Directory of Open Access Journals (Sweden)

Sameh Dardona

2016-08-01

Full Text Available Direct write of a new class of composite materials containing copper and graphene in the powder phase is described. The composite was synthesized using batch electroless plating of copper for various times onto Nano Graphene Platelets (NGP to control the amount of copper deposited within the loosely aggregated graphene powder. Copper deposition was confirmed by both Focused Ion Beam (FIB and Auger electron spectroscopic analysis. A micro-cold spray technique was used to deposit traces that are ∼230 μm wide and ∼5 μm thick of the formulated copper/graphene powder onto a glass substrate. The deposited traces were found to have good adhesion to the substrate with ∼65x the copper bulk resistivity.

Homogeneous forming technology of composite materials and its application to dispersion nuclear fuel

International Nuclear Information System (INIS)

Hong, Soon Hyun; Ryu, Ho Jin; Sohn, Woong Hee; Kim, Chang Kyu

1997-01-01

Powder metallurgy processing technique of metal matrix composites is reviewed and its application to process homogeneous dispersion nuclear fuel is considered. The homogeneous mixing of reinforcement with matrix powders is very important step to process metal matrix composites. The reinforcement with matrix powders is very important step to process metal matrix composites. The reinforcement can be ceramic particles, whiskers or chopped fibers having high strength and high modulus. The blended powders are consolidated into billets and followed by various deformation processing, such as extrusion, forging, rolling or spinning into final usable shapes. Dispersion nuclear fuel is a class of metal matrix composite consisted of dispersed U-compound fuel particles and metallic matrix. Dispersion nuclear fuel is fabricated by powder metallurgy process such as hot pressing followed by hot extrusion, which is similar to that of SiC/Al metal matrix composite. The fabrication of homogeneous dispersion nuclear fuel is very difficult mainly due to the inhomogeneous mixing characteristics of the powders from quite different densities between uranium alloy powders and aluminum powders. In order to develop homogeneous dispersion nuclear fuel, it is important to investigate the effect of powder characteristics and mixing techniques on homogeneity of dispersion nuclear fuel. An new quantitative analysis technique of homogeneity is needed to be developed for more accurate analysis of homogeneity in dispersion nuclear fuel. (author). 28 refs., 7 figs., 1tab

Cold flow testing of the Space Shuttle Main Engine alternate turbopump development high pressure fuel turbine model

Science.gov (United States)

Gaddis, Stephen W.; Hudson, Susan T.; Johnson, P. D.

1992-01-01

NASA's Marshall Space Flight Center has established a cold airflow turbine test program to experimentally determine the performance of liquid rocket engine turbopump drive turbines. Testing of the SSME alternate turbopump development (ATD) fuel turbine was conducted for back-to-back comparisons with the baseline SSME fuel turbine results obtained in the first quarter of 1991. Turbine performance, Reynolds number effects, and turbine diagnostics, such as stage reactions and exit swirl angles, were investigated at the turbine design point and at off-design conditions. The test data showed that the ATD fuel turbine test article was approximately 1.4 percent higher in efficiency and flowed 5.3 percent more than the baseline fuel turbine test article. This paper describes the method and results used to validate the ATD fuel turbine aerodynamic design. The results are being used to determine the ATD high pressure fuel turbopump (HPFTP) turbine performance over its operating range, anchor the SSME ATD steady-state performance model, and validate various prediction and design analyses.

Diesel/CNG Mixture Autoignition Control Using Fuel Composition and Injection Gap

Directory of Open Access Journals (Sweden)

Firmansyah

2017-10-01

Full Text Available Combustion phasing is the main obstacle to the development of controlled auto-ignition based (CAI engines to achieve low emissions and low fuel consumption operation. Fuel combinations with substantial differences in reactivity, such as diesel/compressed natural gas (CNG, show desirable combustion outputs and demonstrate great possibility in controlling the combustion. This paper discusses a control method for diesel/CNG mixture combustion with a variation of fuel composition and fuel stratification levels. The experiments were carried out in a constant volume combustion chamber with both fuels directly injected into the chamber. The mixture composition was varied from 0 to 100% CNG/diesel at lambda 1 while the fuel stratification level was controlled by the injection phasing between the two fuels, with gaps between injections ranging from 0 to 20 ms. The results demonstrated the suppressing effect of CNG on the diesel combustion, especially at the early combustion stages. However, CNG significantly enhanced the combustion performance of the diesel in the later stages. Injection gaps, on the other hand, showed particular behavior depending on mixture composition. Injection gaps show less effect on combustion phasing but a significant effect on the combustion output for higher diesel percentage (≥70%, while it is contradictive for lower diesel percentage (<70%.

Analysis of cold flow fluidization test results for various biomass fuels

Energy Technology Data Exchange (ETDEWEB)

Abdullah, M.Z.; Husain, Z.; Pong, S.L.Y. [University Sains Malaysia, Penang (Malaysia). School of Mechanical Engineering

2003-07-01

A systematic theoretical and experimental study was conducted to obtain hydrodynamic properties such as particle size diameter, bulk density, fluidizing velocity, etc. for locally available biomass residue fuels in Malaysia like rice husk, sawdust, peanut shell, coconut shell, palm fiber as well as coal and bottom ash. The tests were carried out in a cold flow fluidization bed chamber of internal diameter 60 mm with air as fluidizing medium. Bed-pressure drop was measured as a function of superficial air velocity over a range of bed heights for each individual type of particle. The data were used to determine minimum fluidization velocity, which could be used to compare with theoretical values. The particle size of biomass residue fuel was classified according to Gildart's distribution diagram. The results show that Gildart's particle size (B) for sawdust, coal bottom ash, coconut shell have good fluidizing properties compared to rice husk, type (D) or palm fiber, type (A). The bulk density and voidage are found to be main factors contributing to fluidizing quality of the bed.

The erosion performance of cold spray deposited metal matrix composite coatings with subsequent friction stir processing

Energy Technology Data Exchange (ETDEWEB)

Peat, Tom, E-mail: tompeat12@gmail.com [Department of Mechanical & Aerospace Engineering, University of Strathclyde, James Weir Building, 75 Montrose Street, Glasgow G1 1XJ (United Kingdom); Galloway, Alexander; Toumpis, Athanasios [Department of Mechanical & Aerospace Engineering, University of Strathclyde, James Weir Building, 75 Montrose Street, Glasgow G1 1XJ (United Kingdom); McNutt, Philip [TWI Ltd., Granta Park, Cambridge CB21 6AL (United Kingdom); Iqbal, Naveed [TWI Technology Centre, Wallis Way, Catcliff, Rotherham, S60 5TZ (United Kingdom)

2017-02-28

Highlights: • WC-CoCr, Cr{sub 3}C{sub 2}-NiCr and Al{sub 2}O{sub 3} coatings were cold spray deposited on AA5083 and friction stir processed. • The SprayStirred WC-CoCr demonstrated a hardness increase of 100% over the cold sprayed coating. • As-deposited and SprayStirred coatings were examined under slurry erosion test conditions. • Mass and volume loss was measured following 20-min exposure to the slurry. • The WC-CoCr and Al2O3 demonstrated a reduction in volume loss of approx. 40% over the cold sprayed coating. - Abstract: This study forms an initial investigation into the development of SprayStir, an innovative processing technique for generating erosion resistant surface layers on a chosen substrate material. Tungsten carbide – cobalt chromium, chromium carbide – nickel chromium and aluminium oxide coatings were successfully cold spray deposited on AA5083 grade aluminium. In order to improve the deposition efficiency of the cold spray process, coatings were co-deposited with powdered AA5083 using a twin powder feed system that resulted in thick (>300 μm) composite coatings. The deposited coatings were subsequently friction stir processed to embed the particles in the substrate in order to generate a metal matrix composite (MMC) surface layer. The primary aim of this investigation was to examine the erosion performance of the SprayStirred surfaces and demonstrate the benefits of this novel process as a surface engineering technique. Volumetric analysis of the SprayStirred surfaces highlighted a drop of approx. 40% in the level of material loss when compared with the cold spray deposited coating prior to friction stir processing. Micro-hardness testing revealed that in the case of WC-CoCr reinforced coating, the hardness of the SprayStirred material exhibits an increase of approx. 540% over the unaltered substrate and 120% over the as-deposited composite coating. Microstructural examination demonstrated that the increase in the hardness of the

Nanodiamond composite as a material for cold electron emitters

International Nuclear Information System (INIS)

Arkhipov, A V; Sominski, G G; Uvarov, A A; Gordeev, S K; Korchagina, S B

2008-01-01

Characteristics of field-induced electron emission were investigated for one of newly designed all-carbon materials - nanodiamond composite (NDC). The composite is comprised by 4-6 nm diamond grains covered with 0.2-1 nm-thick graphite-like shells that merge at grain junctions and determine such properties as mechanical strength and high electric conductivity. Large number of uniformly distributed sp 3 -sp 2 interfaces allowed to expect enhanced electron emission in electric field. Combination of these features makes NDC a promising material for cold electron emitters in various applications. Experimental testing confirmed high efficiency of electron emission from NDC. In comparison with previousely tested forms of nanocarbon, NDC emitters demonstrated better stabily and tolerance to performance conditions. Unusual activation scenarios and thermal dependencies of emission characteristics observed in experiments with NDC can add new background for explanation of facilitated electron emission from nanocarbons with relatively 'smooth' surface morphology

Catalytic Surface Promotion of Composite Cathodes in Protonic Ceramic Fuel Cells

DEFF Research Database (Denmark)

Solis, Cecilia; Navarrete, Laura; Bozza, Francesco

2015-01-01

Composite cathodes based on an electronic conductor and a protonic conductor show advantages for protonic ceramic fuel cells. In this work, the performance of a La5.5WO11.25-δ/ La0.8Sr0.2MnO3+δ (LWO/LSM) composite cathode in a fuel cell based on an LWO protonic conducting electrolyte is shown...

Thermophysical properties of composite fuel based on T grade coal (Alardinskoe deposit) and timber industry wastes

Science.gov (United States)

Yankovsky, S. A.; Tolokolnikov, A. A.; Gubin, V. E.; Slyusarskiy, K. V.; Zenkov, A. V.

2017-09-01

Results of experimental studies of composite fuel thermal decomposition processes based on T grade coal (Alardinskoe deposit) and timber industry wastes (fine wood) are presented. C, H, N, S weight percentage of each component of composite fuel was determined experimentally. It has been established that with an increase in wood concentration up to 50% in composite fuel, its energy characteristics decrease by less than 3.6%, while the yield of fly ash is 39.7%. An effective composite fuel composition has been defined as 50%/50%. Results of performed experimental studies suggest that it is possible to use composite fuels based on coal and wood at thermal power plants.

Hybrid Composites for LH2 Fuel Tank Structure

Science.gov (United States)

Grimsley, Brian W.; Cano, Roberto J.; Johnston, Norman J.; Loos, Alfred C.; McMahon, William M.

2001-01-01

The application of lightweight carbon fiber reinforced plastics (CFRP) as structure for cryogenic fuel tanks is critical to the success of the next generation of Reusable Launch Vehicles (RLV). The recent failure of the X-33 composite fuel tank occurred in part due to microcracking of the polymer matrix, which allowed cryogen to permeate through the inner skin to the honeycomb core. As part of an approach to solve these problems, NASA Langley Research Center (LaRC) and Marshall Space Flight Center (MSFC) are working to develop and investigate polymer films that will act as a barrier to the permeation of LH2 through the composite laminate. In this study two commercially available films and eleven novel LaRC films were tested in an existing cryogenics laboratory at MSFC to determine the permeance of argon at room temperature. Several of these films were introduced as a layer in the composite to form an interleaved, or hybrid, composite to determine the effects on permeability. In addition, the effects of the interleaved layer thickness, number, and location on the mechanical properties of the composite laminate were investigated. In this initial screening process, several of the films were found to exhibit lower permeability to argon than the composite panels tested.

Burn-up credit criticality safety benchmark phase VII - UO2 fuel: study of spent fuel compositions for long-term disposal

International Nuclear Information System (INIS)

2012-01-01

After spent nuclear fuel (SNF) is discharged from a nuclear reactor, fuel composition and reactivity continue to vary as a function of time due to the decay of unstable nuclides. Accurate predictions of the concentrations of long-lived radionuclides in SNF, which represent a significant potential hazard to human beings and to the environment over a very long period, are particularly necessary for radiological dose assessments. This report assesses the ability of existing computer codes and associated nuclear data to predict isotopic compositions and their corresponding neutron multiplication factor (k eff ) values for pressurised-water-reactor (PWR) UO 2 fuel at 50 GWd/MTU burn-up in a generic spent fuel cask configuration. Fuel decay compositions and k eff values have been calculated for 30 post-irradiation time steps out to one million years

The agnion Heatpipe-Reformer - operating experiences and evaluation of fuel conversion and syngas composition

Energy Technology Data Exchange (ETDEWEB)

Gallmetzer, Georg; Ackermann, Pascal [Highterm Research GmbH, Hettenshausen (Germany); Schweiger, Andreas; Kienberger, Thomas [Highterm Research GmbH, Graz (Austria); Groebl, Thomas; Walter, Heimo [Technische Universitaet Wien, Institut fuer Energietechnik und Thermodynamik, Wien (Austria); Zankl, Markus; Kroener, Martin [Agnion Technologies GmbH, Hettenshausen (Germany)

2012-09-15

Fluidized bed gasification of solid fuels is considered as one of the core technologies for future sustainable energy supply. Whereas autothermal oxygen-driven gasification is applied in large-scale substitute natural gas (SNG) and Fischer-Tropsch (FT) plants or small-scale combined heat and power (CHP) plants, the allothermal steam-reforming process of the agnion Heatpipe-Reformer is designed for cost- and fuel-efficient syngas generation at small scales for distributed applications. The Heatpipe-Reformer's pressurized syngas generation provides a number of benefits for SNG, biomass to liquid (BTL) and CHP applications. A modified gas engine concept uses the pressurized and hydrogen-rich syngas for increased performance and tar tolerance at decreased capital expenses. Agnion has installed and operated a 500-kW thermal input pilot plant in Pfaffenhofen, Germany, over the last 2 years, showing stable operation over a variety of operating points. The syngas composition has been measured at values expected by thermodynamic models. An influence of the steam-to-fuel ratio and reformer temperature was observed. Tar and sulphur contents have been monitored and correlated to operation parameters, showing influences on stoichiometry and carbon conversion. The mass and energy streams of the plant were balanced. One of the main observations in the monitoring programme is the fact that syngas output, efficiency and syngas quality correlate to high values if the carbon conversion is high. Carbon conversion rates and cold gas efficiencies are comparably high in respect to today's processes, promising economic and fuel-efficient operation of the Heatpipe-Reformer applications. (orig.)

Comparison of DUPIC fuel composition heterogeneity control methods

International Nuclear Information System (INIS)

Choi, Hang Bok; Ko, Won Il

1999-08-01

A method to reduce the fuel composition heterogeneity effect on the core performance parameters has been studied for the DUPIC fuel which is made of spent pressurized water reactor (PWR) fuels by a dry refabrication process. This study focuses on the reactivity control method which uses either slightly enriched, depleted, or natural uranium to minimize the cost rise effect on the manufacturing of DUPIC fuel, when adjusting the excess reactivity control by slightly enriched and depleted uranium, reactivity control by natural uranium for high reactivity spent PWR fuels, and reactivity control by natural uranium for linear reactivity spent PWR fuels. The results of this study have shown that the reactivity control by slightly enriched and depleted uranium, all the spent PWR fuels can be utilized as the DUPIC fuel and the fraction of fresh uranium feed is 3.4% on an average. For the reactivity control by natural uranium, about 88% of spent PWR fuel can be utilized as the DUPIC fuel when the linear reactivity spent PWR fuels are used, and the amount of natural uranium feed needed to control the DUPIC fuel reactivity is negligible. (author). 13 refs., 16 tabs., 6 figs

Plutonium isotopic composition of high burnup spent fuel discharged from light water reactors

International Nuclear Information System (INIS)

Nakano, Yoshihiro; Okubo, Tsutomu

2011-01-01

Highlights: → Pu isotopic composition of fuel affects FBR core nuclear characteristics very much. → Spent fuel compositions of next generation LWRs with burnup of 70 GWd/t were obtained. → Pu isotopic composition and amount in the spent fuel with 70 GWd/t were evaluated. → Spectral shift rods of high burnup BWR increases the fissile Pu fraction of spent fuel. → Wide fuel rod pitch of high burnup PWR lowers the fissile Pu fraction of spent fuel. - Abstract: The isotopic composition and amount of plutonium (Pu) in spent fuel from a high burnup boiling water reactor (HB-BWR) and a high burnup pressurized water reactor (HB-PWR), each with an average discharge burnup of 70 GWd/t, were estimated, in order to evaluate fast breeder reactor (FBR) fuel composition in the transition period from LWRs to FBRs. The HB-BWR employs spectral shift rods and the neutron spectrum is shifted through the operation cycle. The weight fraction of fissile plutonium (Puf) isotopes to the total plutonium in HB-BWR spent fuel after 5 years cooling is 62%, which is larger than that of conventional BWRs with average burnup of 45 GWd/t, because of the spectral shift operation. The amount of Pu produced in the HB-BWR is also larger than that produced in a conventional BWR. The HB-PWR uses a wider pitch 17 x 17 fuel rod assembly to optimize neutron slowing down. The Puf fraction of HB-PWR spent fuel after 5 years cooling is 56%, which is smaller than that of conventional PWRs with average burnup of 49 GWd/t, mainly because of the wider pitch. The amount of Pu produced in the HB-PWR is also smaller than that in conventional PWRs.

Prediction of cold flow properties of Biodiesel

Directory of Open Access Journals (Sweden)

Parag Saxena

2016-08-01

Full Text Available Biodiesel being environmentally friendly is fast gaining acceptance in the market as an alternate diesel fuel. But compared to petroleum diesel it has certain limitations and thus it requires further development on economic viability and improvement in its properties to use it as a commercial fuel. The cold flow properties play a major role in the usage of biodiesel commercially as it freezes at cold climatic conditions. In the present study, cold flow properties of various types of biodiesel were estimated by using correlations available in literature. The correlations were evaluated based on the deviation between the predicted value and experimental values of cold flow properties.

Databook of the isotopic composition of spent fuel in light water reactors

International Nuclear Information System (INIS)

Naito, Yoshitaka; Kurosawa, Masayoshi; Kaneko, Toshiyuki.

1993-03-01

In the framework of the activity of the nuclide production evaluation WG in the sigma committee, we summarized the measurement data of the isotopic composition of LWR spent fuels necessary to evaluate the accuracy of the burnup calculation codes. The collected data were arranged to be classified into the irradiation history of the fuel samples, the composition of the fuel assemblies, the sampling position and the isotopic composition of the fuel samples, in order to supply the information necessary to the benchmark calculation. This report describes the data collected from the 13 LWRs including the 9 LWRs (5 PWR and 4 BWR) in Europe and the USA, the 4 LWRs (2 PWR and 2 BWR) in Japan. Finally, the study on the burnup characteristics of the U, Pu isotopes is described. (author)

Nanodiamond composite as a material for cold electron emitters

Energy Technology Data Exchange (ETDEWEB)

Arkhipov, A V; Sominski, G G; Uvarov, A A [St.Petersburg State Polytechnic University, 29 Politchnicheskaya, St.Petersburg, 195251 (Russian Federation); Gordeev, S K; Korchagina, S B [FSUE ' Central Research Institute for Materials' , 8 Paradnaya Street, St.Petersburg, 191014 (Russian Federation)], E-mail: arkhipov@rphf.spbstu.ru

2008-03-15

Characteristics of field-induced electron emission were investigated for one of newly designed all-carbon materials - nanodiamond composite (NDC). The composite is comprised by 4-6 nm diamond grains covered with 0.2-1 nm-thick graphite-like shells that merge at grain junctions and determine such properties as mechanical strength and high electric conductivity. Large number of uniformly distributed sp{sup 3}-sp{sup 2} interfaces allowed to expect enhanced electron emission in electric field. Combination of these features makes NDC a promising material for cold electron emitters in various applications. Experimental testing confirmed high efficiency of electron emission from NDC. In comparison with previousely tested forms of nanocarbon, NDC emitters demonstrated better stabily and tolerance to performance conditions. Unusual activation scenarios and thermal dependencies of emission characteristics observed in experiments with NDC can add new background for explanation of facilitated electron emission from nanocarbons with relatively 'smooth' surface morphology.

Effects of cold light bleaching on the color stability of composite resins

Science.gov (United States)

Cao, Liqun; Huang, Lijuan; Wu, Meisheng; Wei, Hua; Zhao, Shouliang

2015-01-01

To evaluate the effects of cold light bleaching on the color stability of four restorations using a thermocycling stain challenge. 160 specimens (10 mm in diameter and 2 mm thick) were fabricated from 4 composite resins (Gradia Direct-A, Z350XT, Premisa, and Précis) and divided into 4 subgroups. Color was assessed according to the CIEL*a*b* color scale at baseline, after the first cycle of bleaching, after thermocycling stain challenges, and after the second cycle of bleaching. Mean values were compared using three-way analysis of variance, and multiple comparisons of the mean values were performed using the Tukey-Kramer test. All groups showed significant color changes after stain challenge, the color change was more significant in Gradia Direct and Z350XT than in Premisa and Précis. After the second cycle of bleaching, color mostly recovered to its original values. The color stability of Gradia Direct and Z350XT was inferior to that of Premisa and Précis. The discoloration of composite resin materials can be partly removed after cold light bleaching. PMID:26309549

Reforming petroleum-based fuels for fuel cell vehicles : composition-performance relationships

International Nuclear Information System (INIS)

Kopasz, J. P.; Miller, L. E.; Ahmed, S.; Devlin, P. R.; Pacheco, M.

2001-01-01

Onboard reforming of petroleum-based fuels, such as gasoline, may help ease the introduction of fuel cell vehicles to the marketplace. Although gasoline can be reformed, it is optimized to meet the demands of ICEs. This optimization includes blending to increase the octane number and addition of oxygenates and detergents to control emissions. The requirements for a fuel for onboard reforming to hydrogen are quite different than those for combustion. Factors such as octane number and flame speed are not important; however, factors such as hydrogen density, catalyst-fuel interactions, and possible catalyst poisoning become paramount. In order to identify what factors are important in a hydrocarbon fuel for reforming to hydrogen and what factors are detrimental, we have begun a program to test various components of gasoline and blends of components under autothermal reforming conditions. The results indicate that fuel composition can have a large effect on reforming behavior. Components which may be beneficial for ICEs for their octane enhancing value were detrimental to reforming. Fuels with high aromatic and naphthenic content were more difficult to reform. Aromatics were also found to have an impact on the kinetics for reforming of paraffins. The effects of sulfur impurities were dependent on the catalyst. Sulfur was detrimental for Ni, Co, and Ru catalysts. Sulfur was beneficial for reforming with Pt catalysts, however, the effect was dependent on the sulfur concentration

Solid TRU fuels and fuel cycle technology

International Nuclear Information System (INIS)

Ogawa, Toru; Suzuki, Yasufumi

1997-01-01

Alloys and nitrides are candidate solid fuels for transmutation. However, the nitride fuels are preferred to the alloys because they have more favorable thermal properties which allows to apply a cold-fuel concept. The nitride fuel cycle technology is briefly presented

Validation of spent nuclear fuel nuclide composition data using percentage differences and detailed analysis

Energy Technology Data Exchange (ETDEWEB)

Kim, Man Cheol [Chung-Ang Univ., Seoul (Korea, Republic of). School of Energy Systems Engineering

2017-06-15

Nuclide composition data of spent nuclear fuels are important in many nuclear engineering applications. In reactor physics, nuclear reactor design requires the nuclide composition and the corresponding cross sections. In analyzing the radiological health effects of a severe accident on the public and the environment, the nuclide composition in the reactor inventory is among the important input data. Nuclide composition data need to be provided to analyze the possible environmental effects of a spent nuclear fuel repository. They will also be the basis for identifying the origin of unidentified spent nuclear fuels or radioactive materials.

Data book of the isotopic composition of spent fuel in light water reactors

International Nuclear Information System (INIS)

Naito, Yoshitaka; Kurosawa, Masayoshi; Kaneko, Toshiyuki.

1994-03-01

In the framework of the activity of the working group on Evaluation of Nuclide Generation and Depletion in the Japanese Nuclear Data Committee, we summarized the assay data of the isotopic composition of LWR spent fuels in order to verify the accuracy of the burnup calculation codes. The report contains the data collected from the 13 light water reactors (LWRs) including the 9 LWRs (5 PWRs and 4 BWRs) in Europe and USA, the 4 LWRs (2 PWRs and 2 BWRs) in Japan. The collected data were sorted into the irradiation history of the fuel samples, the composition of the fuel assemblies, the sampling position and the isotopic composition of the fuel samples. (author)

Thorium utilisation in a small long-life HTR. Part III: Composite-rod fuel blocks

Energy Technology Data Exchange (ETDEWEB)

Verrue, Jacques, E-mail: jacques.verrue@polytechnique.org [Delft University of Technology, Reactor Institute Delft, Mekelweg 15, 2629 JB Delft (Netherlands); École Polytechnique (Member of ParisTech), 91128 Palaiseau Cedex (France); Ding, Ming, E-mail: dingm2005@gmail.com [Delft University of Technology, Reactor Institute Delft, Mekelweg 15, 2629 JB Delft (Netherlands); Harbin Engineering University, Nantong Street 145, 150001 Harbin (China); Kloosterman, Jan Leen, E-mail: j.l.kloosterman@tudelft.nl [Delft University of Technology, Reactor Institute Delft, Mekelweg 15, 2629 JB Delft (Netherlands)

2014-02-15

Highlights: • Composite-rod fuel blocks are proposed for a small block-type HTR. • An axial separation of fuel compacts is the most important feature. • Three patterns are presented to analyse the effects of the spatial distribution. • The spatial distribution has a large influence on the neutron spectrum. • Composite-rod fuel blocks reach a reactivity swing less than 4%. - Abstract: The U-Battery is a small long-life high temperature gas-cooled reactor (HTR) with power of 20 MWth. In order to increase its lifetime and diminish its reactivity swing, the concept of composite-rod fuel blocks with uranium and thorium was investigated. Composite-rod fuel blocks feature a specific axial separation between UO{sub 2} and ThO{sub 2} compacts in fuel rods. The design parameters, investigated by SCALE 6, include the number and spatial distribution of fuel compacts within the rods, the enrichment of uranium, the radii of fuel kernels and fuel compacts, and the packing fractions of uranium and thorium TRISO particles. The analysis shows that a lower moderation ratio and a larger inventory of heavy metals results in a lower reactivity swing. The optimal atomic carbon-to-heavy metal ratio depends on the mass fraction of U-235 and is commonly in the 160–200 range. The spatial distribution of the fuel compacts within the fuel rods has a large influence on the energy spectrum in each fuel compact and thus on the beginning-of-life reactivity and the reactivity swing. At end-of-life, the differences caused by the spatial distribution of the fuel compacts are smaller due to the fissions of U-233 in the ThO{sub 2} fuel compacts. This phenomenon enables to design fuel blocks with a very low reactivity swing, down to less than 4% in a 10-year lifetime. Among three types of thorium fuelled U-Battery blocks, the composite-rod fuel block achieves the highest end-of-life reactivity and the lowest reactivity swing.

Chemical composition and oxidative stability of jussara (Euterpe edulis M.) oil extracted by cold and hot mechanical pressing

International Nuclear Information System (INIS)

Da Cunha, A.L.A.; Freitas, S.P.; Godoy, R.L.O.; Cabral, L.M.C.; Tonon, R.V.

2017-01-01

The aim of this work was to evaluate the effect of mechanical pressing on jussara oil yield, oxidative stability and carotenoid profile with or without heat application. Firstly, jussara pulp was centrifuged for juice extraction, and the resulting cake was dried until reaching 10% moisture content. Then, oil extraction was performed in an expeller press at 25 ºC (cold pressing) and at 50 ºC (hot pressing). The process performance was evaluated by the oil yield, and the crude jussara oil was characterized for fatty acid composition, acid value, carotenoid profile and oxidative stability. Jussara oil contained 74% unsaturated fatty acids, mainly oleic and linoleic acids (48% and 24%, respectively). The oil yield was almost twice as high for the hot process as compared to the cold one. Additionally, hot pressing resulted in 25% higher total carotenoid content as compared to cold pressing, with β-carotene as the most abundant one. Hot and cold pressing showed no difference in oil oxidative stability and fatty acid composition. [es

Effect of variation in LPG composition on emissions and performance in a dual fuel diesel engine

Energy Technology Data Exchange (ETDEWEB)

H.E. Saleh [Mattaria, Helwan University, Cairo (Egypt). Department of Mechanical Power Engineering

2008-10-15

This paper investigates the effect of variation in LPG composition on emissions and performance characteristics in a dual fuel engine run on diesel fuel and five gaseous fuel of LPG with different composition. To quantify the best LPG composition for dual fuel operation especially in order to improve the exhaust emissions quality while maintaining high thermal efficiency comparable to a conventional diesel engine, a two-cylinder, naturally aspirated, four-stroke, DI diesel engine converted to run as pilot-injected dual fuel engine. The tests and data collection were performed under various conditions of load at constant engine speed. From the results, it is observed that the exhaust emissions and fuel conversion efficiency of the dual fuel engine are found to be affected when different LPG composition is used as higher butane content lead to lower NOx levels while higher propane content reduces CO levels. Fuel No. 3 (70% propane, 30% butane) with mass fraction 40% substitution of the diesel fuel was the best LPG composition in the dual fuel operation except that at part loads. Also, tests were made for fuel No. 3-diesel blend in the dual fuel operation at part loads to improve the engine performances and exhaust emissions by using the Exhaust Gas Recirculation (EGR) method. 26 refs., 15 figs., 5 tabs.

Fuel composition effects on HYPER core characteristics

International Nuclear Information System (INIS)

Han, Chi Young; Kim, Yong Nam; Kim, Jong Kyung

2001-01-01

At KAERI(Korea Atomic Energy Research Institute), a subcritical transmutation reactor is under development, named HYPER(Hybrid Power Extraction Reactor). For the HYPER system, a pyrochemical process is being considered for fuel reprocessing. Separated from the separation process, the fuel contains not only TRU but also the considerable percentages of impurity such as uranium nuclides and lanthanides. The amount of these impurities depends on strongly the refining efficiency of the reprocessing and may change the core characteristics. This paper has analyzed fuel composition effects on th HYPER core characteristics. Assuming various recovery factors of uranium and lanthanides, some dynamic parameters have been evaluated which are the neutron spectrum, the neutron reaction balance, the reactivity coefficients, the effective delayed neutron fraction, and the effective neutron lifetime

Corrosion of graphite composites in phosphoric acid fuel cells

Science.gov (United States)

Christner, L. G.; Dhar, H. P.; Farooque, M.; Kush, A. K.

1986-01-01

Polymers, polymer-graphite composites and different carbon materials are being considered for many of the fuel cell stack components. Exposure to concentrated phosphoric acid in the fuel cell environment and to high anodic potential results in corrosion. Relative corrosion rates of these materials, failure modes, plausible mechanisms of corrosion and methods for improvement of these materials are investigated.

Fructan metabolism and changes in fructan composition during cold acclimation in perennial ryegrass

Science.gov (United States)

Abeynayake, Shamila W.; Etzerodt, Thomas P.; Jonavičienė, Kristina; Byrne, Stephen; Asp, Torben; Boelt, Birte

2015-01-01

Perennial ryegrass (Lolium perenne L.) produces high levels of fructans as a mixture of oligosaccharides and polysaccharides with different degrees of polymerization (DP). The present study describes the analysis of the compositional changes in the full spectrum of fructans, fructan distribution between above ground biomass (top) and the roots, and the transcription of candidate genes involved in fructan metabolism during cold acclimation in perennial ryegrass variety “Veyo” and ecotype “Falster” from distinct geographical origins. We observed changes in fructan composition and induction of low-DP fructans, especially DP = 4, in both the top and the roots of “Veyo” and “Falster” in response to low-temperature stress. The accumulation of DP > 50 fructans was only apparent in the top tissues where the Lp1-FFT expression is higher compared to the roots in both “Veyo” and “Falster.” Our results also show the accumulation and depolymerization of fructans with different DP, together with the induction of genes encoding fructosyltransferases and fructan exohydrolases in both “Veyo” and “Falster” during cold acclimation, supporting the hypothesis that fructan synthesis and depolymerization occurring simultaneously. The ecotype “Falster,” adapted to cold climates, increased total fructan content and produced more DP > 7 fructans in the roots than the variety “Veyo,” adapted to warmer climates. This indicates that high-DP fructan accumulation in roots may be an adaptive trait for plant recovery after abiotic stresses. PMID:26029229

Carbon composites with metal nanoparticles for Alcohol fuel cells

Science.gov (United States)

Ventrapragada, Lakshman; Siddhardha, R. S.; Podilla, Ramakrishna; Muthukumar, V. S.; Creager, Stephen; Rao, A. M.; Ramamurthy, Sai Sathish

2015-03-01

Graphene due to its high surface area and superior conductivity has attracted wide attention from both industrial and scientific communities. We chose graphene as a substrate for metal nanoparticle deposition for fuel cell applications. There are many chemical routes for fabrication of metal-graphene composites, but they have an inherent disadvantage of low performance due to the usage of surfactants, that adsorb on their surface. Here we present a design for one pot synthesis of gold nanoparticles and simultaneous deposition on graphene with laser ablation of gold strip and functionalized graphene. In this process there are two natural advantages, the nanoparticles are synthesized without any surfactants, therefore they are pristine and subsequent impregnation on graphene is linker free. These materials are well characterized with electron microscopy to find their morphology and spectroscopic techniques like Raman, UV-Vis. for functionality. This gold nanoparticle decorated graphene composite has been tested for its electrocatalytic oxidation of alcohols for alkaline fuel cell applications. An electrode made of this composite showed good stability for more than 200 cycles of operation and reported a low onset potential of 100 mV more negative, an important factor for direct ethanol fuel cells.

VOC composition of current motor vehicle fuels and vapors, and collinearity analyses for receptor modeling.

Science.gov (United States)

Chin, Jo-Yu; Batterman, Stuart A

2012-03-01

The formulation of motor vehicle fuels can alter the magnitude and composition of evaporative and exhaust emissions occurring throughout the fuel cycle. Information regarding the volatile organic compound (VOC) composition of motor fuels other than gasoline is scarce, especially for bioethanol and biodiesel blends. This study examines the liquid and vapor (headspace) composition of four contemporary and commercially available fuels: gasoline (gasoline), ultra-low sulfur diesel (ULSD), and B20 (20% soy-biodiesel and 80% ULSD). The composition of gasoline and E85 in both neat fuel and headspace vapor was dominated by aromatics and n-heptane. Despite its low gasoline content, E85 vapor contained higher concentrations of several VOCs than those in gasoline vapor, likely due to adjustments in its formulation. Temperature changes produced greater changes in the partial pressures of 17 VOCs in E85 than in gasoline, and large shifts in the VOC composition. B20 and ULSD were dominated by C(9) to C(16)n-alkanes and low levels of the aromatics, and the two fuels had similar headspace vapor composition and concentrations. While the headspace composition predicted using vapor-liquid equilibrium theory was closely correlated to measurements, E85 vapor concentrations were underpredicted. Based on variance decomposition analyses, gasoline and diesel fuels and their vapors VOC were distinct, but B20 and ULSD fuels and vapors were highly collinear. These results can be used to estimate fuel related emissions and exposures, particularly in receptor models that apportion emission sources, and the collinearity analysis suggests that gasoline- and diesel-related emissions can be distinguished. Copyright © 2011 Elsevier Ltd. All rights reserved.

Influence of Chemical Blends on Palm Oil Methyl Esters’ Cold Flow Properties and Fuel Characteristics

Directory of Open Access Journals (Sweden)

Obed M. Ali

2014-07-01

Full Text Available Alternative fuels, like biodiesel, are being utilized as a renewable energy source and an effective substitute for the continuously depleting supply of mineral diesel as they have similar combustion characteristics. However, the use of pure biodiesel as a fuel for diesel engines is currently limited due to problems relating to fuel properties and its relatively poor cold flow characteristics. Therefore, the most acceptable option for improving the properties of biodiesel is the use of a fuel additive. In the present study, the properties of palm oil methyl esters with increasing additive content were investigated after addition of ethanol, butanol and diethyl ether. The results revealed varying improvement in acid value, density, viscosity, pour point and cloud point, accompanied by a slight decrease in energy content with an increasing additive ratio. The viscosity reductions at 5% additive were 12%, 7%, 16.5% for ethanol, butanol and diethyl ether, respectively, and the maximum reduction in pour point was 5 °C at 5% diethyl ether blend. Engine test results revealed a noticeable improvement in engine brake power and specific fuel consumption compared to palm oil biodiesel and the best performance was obtained with diethyl ether. All the biodiesel-additive blend samples meet the requirements of ASTM D6751 biodiesel fuel standards for the measured properties.

Cold vacuum drying facility site evaluation report

International Nuclear Information System (INIS)

Diebel, J.A.

1996-01-01

In order to transport Multi-Canister Overpacks to the Canister Storage Building they must first undergo the Cold Vacuum Drying process. This puts the design, construction and start-up of the Cold Vacuum Drying facility on the critical path of the K Basin fuel removal schedule. This schedule is driven by a Tri-Party Agreement (TPA) milestone requiring all of the spent nuclear fuel to be removed from the K Basins by December, 1999. This site evaluation is an integral part of the Cold Vacuum Drying design process and must be completed expeditiously in order to stay on track for meeting the milestone

Diesel Surrogate Fuels for Engine Testing and Chemical-Kinetic Modeling: Compositions and Properties.

Science.gov (United States)

Mueller, Charles J; Cannella, William J; Bays, J Timothy; Bruno, Thomas J; DeFabio, Kathy; Dettman, Heather D; Gieleciak, Rafal M; Huber, Marcia L; Kweon, Chol-Bum; McConnell, Steven S; Pitz, William J; Ratcliff, Matthew A

2016-02-18

The primary objectives of this work were to formulate, blend, and characterize a set of four ultralow-sulfur diesel surrogate fuels in quantities sufficient to enable their study in single-cylinder-engine and combustion-vessel experiments. The surrogate fuels feature increasing levels of compositional accuracy (i.e., increasing exactness in matching hydrocarbon structural characteristics) relative to the single target diesel fuel upon which the surrogate fuels are based. This approach was taken to assist in determining the minimum level of surrogate-fuel compositional accuracy that is required to adequately emulate the performance characteristics of the target fuel under different combustion modes. For each of the four surrogate fuels, an approximately 30 L batch was blended, and a number of the physical and chemical properties were measured. This work documents the surrogate-fuel creation process and the results of the property measurements.

Roasting pumpkin seeds and changes in the composition and oxidative stability of cold-pressed oils.

Science.gov (United States)

Raczyk, Marianna; Siger, Aleksander; Radziejewska-Kubzdela, Elżbieta; Ratusz, Katarzyna; Rudzińska, Magdalena

2017-01-01

Pumpkin seed oil is valuable oil for its distinctive taste and aroma, as well as supposed health- promoting properties. The aim of this study was to investigate how roasting pumpkin seeds influences the physicochemical properties of cold-pressed oils. The fatty acid composition, content of phytosterols, carotenoids and tocopherols, oxidative stability and colour were determined in oils after cold pressing and storage for 3 months using GC-FID, GCxGC-ToFMS, HPLC, Rancimat and spectrophotometric methods. The results of this study indicate that the seed-roasting and storage process have no effect on the fatty acid composition of pumpkin seed oils, but does affect phytosterols and tocopherols. The carotenoid content decreased after storage. The colour of the roasted oil was darker and changed significantly during storage. Pumpkin oil obtained from roasted seeds shows better physicochemical properties and oxidative stability than oil from unroasted seeds.

Simultaneous measurement of current and temperature distributions in a proton exchange membrane fuel cell during cold start processes

International Nuclear Information System (INIS)

Jiao Kui; Alaefour, Ibrahim E.; Karimi, Gholamreza; Li Xianguo

2011-01-01

Cold start is critical to the commercialization of proton exchange membrane fuel cell (PEMFC) in automotive applications. Dynamic distributions of current and temperature in PEMFC during various cold start processes determine the cold start characteristics, and are required for the optimization of design and operational strategy. This study focuses on an investigation of the cold start characteristics of a PEMFC through the simultaneous measurements of current and temperature distributions. An analytical model for quick estimate of purging duration is also developed. During the failed cold start process, the highest current density is initially near the inlet region of the flow channels, then it moves downstream, reaching the outlet region eventually. Almost half of the cell current is produced in the inlet region before the cell current peaks, and the region around the middle of the cell has the best survivability. These two regions are therefore more important than other regions for successful cold start through design and operational strategy, such as reducing the ice formation and enhancing the heat generation in these two regions. The evolution of the overall current density distribution over time remains similar during the successful cold start process; the current density is the highest near the flow channel inlets and generally decreases along the flow direction. For both the failed and the successful cold start processes, the highest temperature is initially in the flow channel inlet region, and is then around the middle of the cell after the overall peak current density is reached. The ice melting and liquid formation during the successful cold start process have negligible influence on the general current and temperature distributions.

Cold-neutron tomography of annular flow and functional spacer performance in a model of a boiling water reactor fuel rod bundle

International Nuclear Information System (INIS)

Zboray, Robert; Kickhofel, John; Damsohn, Manuel; Prasser, Horst-Michael

2011-01-01

Highlights: → Annular flows w/wo functional spacers are investigated by cold neutron imaging. → Liquid film thickness distribution on fuel pins and on spacer vanes is measured. → The influence of the spacers on the liquid film distributions has been quantified. → The cross-sectional averaged liquid hold-up significantly affected by the spacers. → The sapers affect the fraction of the entrained liquid hold up in the gas core. - Abstract: Dryout of the coolant liquid film at the upper part of the fuel pins of a boiling water reactor (BWR) core constitutes the type of heat transfer crisis relevant for the conditions of high void fractions. It is both a safety concern and a limiting factor in the thermal power and thus for the economy of BWRs. We have investigated adiabatic, air-water annular flows in a scaled-up model of two neighboring subchannels as found in BWR fuel assemblies using cold-neutron tomography. The imaging of the double suchannel has been performed at the ICON beamline at the neutron spallation source SINQ at the Paul Scherrer Institute, Switzerland. Cold-neutron tomography is shown here to be an excellent tool for investigating air-water annular flows and the influence of functional spacers of different geometries on such flows. The high-resolution, high-contrast measurements provide the spatial distributions of the coolant liquid film thickness on the fuel pin surfaces as well as on the surfaces of the spacer vanes. The axial variations of the cross-section averaged liquid hold-up and its fraction in the gas core shows the effect of the spacers on the redistribution of the two phases.

Assessment of microalgae biodiesel fuels using a fuel property estimation methodology

Energy Technology Data Exchange (ETDEWEB)

Torrens, Jonas Colen Ladeia; Vargas, Jose Viriato Coelho; Mariano, Andre Bellin [Center for Research and Development of Sustainable Energy. Universidade Federal do Parana, Curitiba, PR (Brazil)

2010-07-01

Recently, depleting supplies of petroleum and the concerns about global warming are drawing attention to alternative sources of energy. In this context, advanced biofuels, derived from non edible superior plants and microorganisms, are presented as promising options for the transportation sector. Biodiesel, which is the most prominent alternative fuel for compression ignition engines, have a large number as potential feedstock, such as plants (e.g., soybean, canola, palm) and microorganism (i.e., microalgae, yeast, fungi and bacterium). In order to determine their potential, most studies focus on the economic viability, but few discuss the technical viability of producing high quality fuels from such feedstock. Since the fuel properties depend on the composition of the parent oil, and considering the variability of the fatty acid profile found in these organisms, it is clear that the fuels derived may present undesirable properties, e.g., high viscosity, low cetane number, low oxidative stability and poor cold flow properties. Therefore, it is very important to develop ways of analysing the fuel quality prior to production, specially considering the high cost of producing and testing several varieties of plants and microorganisms. In this aim, this work presents the use of fuel properties estimation methods on the assessment of the density, viscosity, cetane number and cold filter plugging point of several microalgae derived biofuels, comparing then to more conventional biodiesel fuels. The information gathered with these methods helps on the selection of species and cultivation parameters, which have a high impact on the derived fuel quality, and have been successfully employed on the Center for Research and Development of Sustainable Energy. The results demonstrate that some species of microalgae have the potential to produce high quality biodiesel if cultivated with optimised conditions, associated with the possibility of obtaining valuable long chain

SFCOMPO: A new database of isotopic compositions of spent nuclear fuel

International Nuclear Information System (INIS)

Michel-Sendis, Franco; Gauld, Ian

2014-01-01

The numerous applications of nuclear fuel depletion simulations impact all areas related to nuclear safety. They are at the basis of, inter alia, spent fuel criticality safety analyses, reactor physics calculations, burn-up credit methodologies, decay heat thermal analyses, radiation shielding, reprocessing, waste management, deep geological repository safety studies and safeguards. Experimentally determined nuclide compositions of well-characterised spent nuclear fuel (SNF) samples are used to validate the accuracy of depletion code predictions for a given burn-up. At the same time, the measured nuclide composition of the sample is used to determine the burn-up of the fuel. It is therefore essential to have a reliable and well-qualified database of measured nuclide concentrations and relevant reactor operational data that can be used as experimental benchmark data for depletion codes and associated nuclear data. The Spent Fuel Isotopic Composition Database (SFCOMPO) has been hosted by the NEA since 2001. In 2012, a collaborative effort led by the NEA Data Bank and Oak Ridge National Laboratory (ORNL) in the United States, under the guidance of the NEA Expert Group on Assay Data of Spent Nuclear Fuel (EGADSNF) of the Working Party on Nuclear Criticality Safety (WPNCS), has resulted in the creation of an enhanced relational database structure and a significant expansion of the SFCOMPO database, which now contains experimental assay data for a wider selection of international reactor designs. The new database was released online in 2014. This new SFCOMPO database aims to provide access to open experimental SNF assay data to ensure their preservation and to facilitate their qualification as evaluated assay data suitable for the validation of methodologies used to predict the composition of irradiated nuclear fuel. Having a centralised, internationally reviewed database that makes these data openly available for a large selection of international reactor designs is of

Influence of fuel composition on the spent fuel verification by Self‑Interrogation Neutron Resonance Densitometry

International Nuclear Information System (INIS)

Rossa, Riccardo; Borella, Alessandro; Van der Meer, Klaas; Labeau, Pierre‑Etienne; Pauly, Nicolas

2015-01-01

The Self‑Interrogation Neutron Resonance Densitometry (SINRD) is a passive Non‑Destructive Assay (NDA) that is developed for the safeguards verification of spent nuclear fuel. The main goal of SINRD is the direct quantification of 239Pu by estimating the SINRD signature, which is the ratio between the neutron flux in the fast energy region and in the region close to the 0.3 eV resonance of 239 Pu. The resonance region was chosen because the reduction of the neutron flux within 0.2-0.4 eV is due mainly to neutron absorption from 239 Pu, and therefore the SINRD signature can be correlated to the 239Pu mass in the fuel assembly. This work provides an estimate of the influence of 239 Pu and other nuclides on the SINRD signature. This assessment is performed by Monte Carlo simulations by introducing several nuclides in the fuel material composition and by calculating the SINRD signature for each case. The reference spent fuel library developed by SCK CEN was used for the detailed fuel compositions of PWR 17x17 fuel assemblies with different initial enrichments, burnup, and cooling times. The results from the simulations show that the SINRD signature is mainly correlated to the 239 Pu mass, with significant influence by 235 U. Moreover, the SINRD technique is largely insensitive to the cooling time of the assembly, while it is affected by the burnup and initial enrichment of the fuel. Apart from 239 Pu and 235 U, many other nuclides give minor contributions to the SINRD signature, especially at burnup higher than 20 GWd/tHM.

Glass/Ceramic Composites for Sealing Solid Oxide Fuel Cells

Science.gov (United States)

Bansal, Narottam P.; Choi, Sung R.

2007-01-01

A family of glass/ceramic composite materials has been investigated for use as sealants in planar solid oxide fuel cells. These materials are modified versions of a barium calcium aluminosilicate glass developed previously for the same purpose. The composition of the glass in mole percentages is 35BaO + 15CaO + 5Al2O3 + 10B2O3 + 35SiO2. The glass seal was found to be susceptible to cracking during thermal cycling of the fuel cells. The goal in formulating the glass/ ceramic composite materials was to (1) retain the physical and chemical advantages that led to the prior selection of the barium calcium aluminosilicate glass as the sealant while (2) increasing strength and fracture toughness so as to reduce the tendency toward cracking. Each of the composite formulations consists of the glass plus either of two ceramic reinforcements in a proportion between 0 and 30 mole percent. One of the ceramic reinforcements consists of alumina platelets; the other one consists of particles of yttria-stabilized zirconia wherein the yttria content is 3 mole percent (3YSZ). In preparation for experiments, panels of the glass/ceramic composites were hot-pressed and machined into test bars.

Composite fuels. Defining a strategy for better Pu utilization in PWRs

Energy Technology Data Exchange (ETDEWEB)

Porta, Jacques; Baldi, Stefano [DRN/DER/SIS CE Cadarache Bat. 211, 13108 St. Paul lez Durance CEDEX (France); Puill, Andre; Aillaud, Cecile

1999-07-01

After a description of the French context dominated by the accumulation of plutonium, and the international context in which the tendency is towards the disappearance of plutonium reserves and the destruction of minor actinides, a few solutions selected in the framework of the Innovating Fuels programme are presented. The aim is to burn the surplus Pu by means of fuel in inert matrices since, in addition to the increased burnup, the absence of plutonium generating conversion must be considered. The experiments intended to qualify selected CERCERs and CERMETs are presented and discussed, the feasibility of CERMET UO2 and MOX cores is established. Things are more complicated for PuO2 CERMET and we show that, in order to optimize loading, a dedicated heterogeneous assembly has to be defined. The Advanced Plutonium Assembly (APA) is presented. The last part of this article is devoted to the first fabrication tests on these very particular fuels and to the definition of reference accidents liable to affect 'cold' fuels such as CERMETs. (author)

Composite fuels. Defining a strategy for better Pu utilization in PWRs

International Nuclear Information System (INIS)

Porta, Jacques; Baldi, Stefano; Puill, Andre; Aillaud, Cecile

1999-01-01

After a description of the French context dominated by the accumulation of plutonium, and the international context in which the tendency is towards the disappearance of plutonium reserves and the destruction of minor actinides, a few solutions selected in the framework of the Innovating Fuels programme are presented. The aim is to burn the surplus Pu by means of fuel in inert matrices since, in addition to the increased burnup, the absence of plutonium generating conversion must be considered. The experiments intended to qualify selected CERCERs and CERMETs are presented and discussed, the feasibility of CERMET UO2 and MOX cores is established. Things are more complicated for PuO2 CERMET and we show that, in order to optimize loading, a dedicated heterogeneous assembly has to be defined. The Advanced Plutonium Assembly (APA) is presented. The last part of this article is devoted to the first fabrication tests on these very particular fuels and to the definition of reference accidents liable to affect 'cold' fuels such as CERMETs. (author)

Experimental study of dual fuel engine performance using variable LPG composition and engine parameters

International Nuclear Information System (INIS)

Elnajjar, Emad; Selim, Mohamed Y.E.; Hamdan, Mohammad O.

2013-01-01

Highlights: • The effect of using variable LPG is studied. • Five fuels with propane to butane % volume ratio are: 100-70-55-25-0. • 100% Propane composition shows the highest noise levels with similar performance. • At 45° BTDC injection timing 55% Propane LPG the only fuel experience knocking. • LPG fuels gave similar engine performance, with differences in levels of noise. - Abstract: The present work investigates experimentally the effect of LPG fuel with different composition and engine parameters on the performance of a dual compression engine. Five different blends of LPG fuels are used with Propane to Butane volume ratio of 100:0, 70:30, 55:45, 25:75, and 0:100. A single cylinder, naturally aspirated, four strokes, indirectly injected, water cooled modified Ricardo E6 engine, is used in this study. The study is carried out by measuring the cylinder pressure, engine load, engine speed, crank angle, and the fuel’s flow rate. The engine performance under variable LPG fuel composition, engine load, pilot fuel injection timing, compression ratio, pilot fuel mass and engine speed, are estimated by comparing the following engine parameters: the cylinder maximum pressure, the indicated mean effective pressure, the maximum rate of pressure rise, and the thermal efficiency. The experimental data indicates that the engine parameters are playing a major role on the engine’s performance. Different LPG fuel composition did not show a major effect on the engine efficiency but directly impacted the levels of generated combustion noise

Thermal modeling of the ceramic composite fuel for light water reactors

International Nuclear Information System (INIS)

Revankar, S.T.; Latta, R.; Solomon, A.A.

2005-01-01

Full text of publication follows: Composite fuel designs capable of providing improved thermal performance are of great interest in advanced reactor designs where high efficiency and long fuel cycles are desired. Thermal modeling of the composite fuel consisting of continuous second phase in a ceramic (uranium oxide) matrix has been carried out with detailed examination of the microstructure of the composite and the interface. Assuming that constituent phases are arranged as slabs, upper and lower bounds for the thermal conductivity of the composite are derived analytically. Bounding calculations on the thermal conductivity of the composite were performed for SiC dispersed in the UO 2 matrix. It is found that with 10% SiC, the thermal conductivity increases from 5.8 to 9.8 W/m.deg. K at 500 K, or an increase of 69% was observed in UO 2 matrix. The finite element analysis computer program ANSYS was used to create composite fuel geometries with set boundary conditions to produce accurate thermal conductivity predictions. A model developed also accounts for SiC-matrix interface resistance and the addition of coatings or interaction barriers. The first set of calculations using the code was to model simple series and parallel fuel slab geometries, and then advance to inter-connected parallel pathways. The analytical calculations were compared with the ANSYS results. The geometry of the model was set up as a 1 cm long by 400 micron wide rectangle. This rectangle was then divided into one hundred sections with the first ninety percent of a single section being UO 2 and the remaining ten percent consisting of SiC. The model was then meshed using triangular type elements. The boundary conditions were set with the sides of the rectangle being adiabatic and having an assigned temperature at the end of the rectangle. A heat flux was then applied to one end of the model producing a temperature gradient. The effective thermal conductivity was then calculated using the geometry

Composite fuel behaviour under and after irradiation

International Nuclear Information System (INIS)

Dehaudt, P.; Mocellin, A.; Eminet, G.; Caillot, L.; Delette, G.; Bauer, M.; Viallard, I.

1997-01-01

Two kinds of composite fuels have been irradiated in the SILOE reactor. They are made of UO 2 particles dispersed in a molybdenum metallic (CERMET) or a MgAl 2 O 4 ceramic (CERCER) matrix. The irradiation conditions have allowed to reach a 50000 MWd/t U burn-up in these composite fuels after a hundred equivalent full power days long irradiation. The irradiation is controlled by a continuous measure of the pellet centre line temperature. It allows to have information about the TANOX rods thermal behaviour and the fuels thermal conductivities in comparing the centre line temperature versus linear power curves among themselves. Our results show that the CERMET centre line temperature is much lower than the CERCER and UO 2 ones: 520 deg. C against 980 deg. C at a 300W/cm linear power. After pin puncturing tests the rods are dismantled to recover each fuel pellet. In the CERCER case, the cladding peeling off has revealed that the fuel came into contact with the cladding and that some of the pellets were linked together. Optical microscopy observations show a changing of the MgAl 2 O 4 matrix state around the UO 2 particles at the pellets periphery. This transformation may have caused a swelling and would be at the origin of the pellet-cladding and the pellet-pellet interactions. No specific damage is seen after irradiation. The CERMET pellets are not cracked and remain as they were before irradiation. The CERCER crack network is slightly different from that observed in UO 2 . Kr retention was evaluated by annealing tests under vacuum at 1580 deg. C or 1700 deg. C for 30 minutes. The CERMET fission gas release is lower than the CERCER one. Inter- and intragranular fission gas bubbles are observed in the UO 2 particles after heat treatments. The CERCER pellet periphery has also cracked and the matrix has transformed again around UO 2 particles to present a granular and porous aspect. (author). 4 refs, 6 figs, 2 tabs

The influence of weather and fuel type on the fuel composition of the area burned by forest fires in Ontario, 1996-2006.

Science.gov (United States)

Podur, Justin J; Martell, David L

2009-07-01

Forest fires are influenced by weather, fuels, and topography, but the relative influence of these factors may vary in different forest types. Compositional analysis can be used to assess the relative importance of fuels and weather in the boreal forest. Do forest or wild land fires burn more flammable fuels preferentially or, because most large fires burn in extreme weather conditions, do fires burn fuels in the proportions they are available despite differences in flammability? In the Canadian boreal forest, aspen (Populus tremuloides) has been found to burn in less than the proportion in which it is available. We used the province of Ontario's Provincial Fuels Database and fire records provided by the Ontario Ministry of Natural Resources to compare the fuel composition of area burned by 594 large (>40 ha) fires that occurred in Ontario's boreal forest region, a study area some 430,000 km2 in size, between 1996 and 2006 with the fuel composition of the neighborhoods around the fires. We found that, over the range of fire weather conditions in which large fires burned and in a study area with 8% aspen, fires burn fuels in the proportions that they are available, results which are consistent with the dominance of weather in controlling large fires.

Cold weather effects on Dresden Unit 1

Energy Technology Data Exchange (ETDEWEB)

Anagnostopoulos, H. [Commonwealth Edison Co., Morris, IL (United States)

1995-03-01

Dresden Unit 1 is in the final stages of a decommissioning effort directed at preparing the unit to enter a SAFSTOR status. Following an extended sub-zero cold wave, about 55,000 gallons of water were discovered in the lowest elevation of the spherical reactor enclosure. Cold weather had caused the freezing and breaking of several service water lines that had not been completely isolated. Two days later, at a regularly scheduled decommissioning meeting, the event was communicated to the decommissioning team, who quickly recognized the potential for freezing of a 42 inches diameter Fuel Transfer Tube that connects the sphere to the Spent Fuel Pool. The team directed that the pool gates between the adjacent Spent Fuel Pool and the Fuel Transfer Pool be installed, and a portable source of heat was installed on the Fuel Transfer Tube. It was later determined that, with the fuel pool gates removed, and with a worst case freeze break at the 502 elevation on the Fuel Transfer Tube (in the Sphere), the fuel in the Spent Fuel Pool could be uncovered to a level 3 below the top of active fuel.

305 Building Cold Test Facility Management Plan

International Nuclear Information System (INIS)

Whitehurst, R.

1994-01-01

This document provides direction for the conduct of business in Building 305 for cold testing tools and equipment. The Cold Test Facility represents a small portion of the overall building, and as such, the work instructions already implemented in the 305 Building will be utilized. Specific to the Cold Test there are three phases for the tools and equipment as follows: 1. Development and feature tests of sludge/fuel characterization equipment, fuel containerization equipment, and sludge containerization equipment to be used in K-Basin. 2. Functional and acceptance tests of all like equipment to be installed and operated in K-Basin. 3. Training and qualification of K-Basin Operators on equipment to be installed and operated in the Basin

Lanthanum gallate and ceria composite as electrolyte for solid oxide fuel cells

International Nuclear Information System (INIS)

Li Shuai; Li Zhicheng; Bergman, Bill

2010-01-01

The composite of doped lanthanum gallate (La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 2.85 , LSGM) and doped ceria (Ce 0.8 Sm 0.2 O 1.9 , CSO) was investigated as an electrolyte for solid oxide fuel cell (SOFC). The LSGM-CSO composite was examined by X-ray diffraction (XRD) and impedance spectroscopy. It was found that the sintered LSGM-CSO composite contains mainly fluorite CeO 2 phase and a minority impurity phase, Sm 3 Ga 5 O 12 . The LSGM-CSO composite electrolyte shows a small grain boundary response in the impedance spectroscopy as compared to LSGM and CSO pellets. The composite electrolyte exhibits the highest conductivity in the temperature range of 250-600 o C, compared to LSGM and CSO. The LSGM-CSO composite can be expected to be an attractive intermediate temperature electrolyte material for solid oxide fuel cells.

The Influence Of Mass Fraction Of Dressed Coal On Ignition Conditions Of Composite Liquid Fuel Droplet

Directory of Open Access Journals (Sweden)

Shlegel Nikita E.

2015-01-01

Full Text Available The laws of condition modification of inert heat and ignition in an oxidant flow of composite liquid fuel droplet were studied by the developed experimental setup. Investigations were for composite liquid fuel composition based on the waste of bituminous and nonbaking coal processing, appropriate carbon dust, water, used motor oil. The characteristics of boundary layer inertia heat of composite liquid fuel droplet, thermal decomposition of coal organic part, the yield of volatiles and evaporation of liquid combustion component, ignition of the gas mixture and coke residue were defined.

Fast reactor core design studies to cope with TRU fuel composition changes in the LWR-to-FBR transition period

International Nuclear Information System (INIS)

Kawashima, Katsuyuki; Maruyama, Shuhei; Ohki, Shigeo; Mizuno, Tomoyasu

2009-01-01

As part of the Fast Reactor Cycle Technology Development Project (FaCT Project), sodium-cooled fast reactor core design efforts have been made to cope with the TRU fuel composition changes expected during LWR-to-FBR transition period, in which a various kind of TRU fuel compositions are available depending on the characteristics of the LWR spent fuels and a way of recycling them. A 750 MWe mixed-oxide fuel core is firstly defined as a FaCT medium-size reference core and its neutronics characteristics are determined. The core is a high internal conversion type and has an average burnup of 150 GWD/T. The reference TRU fuel composition is assumed to come from the FBR equilibrium state. Compared to the LWR-to-FBR transition period, the TRU fuels in the FBR equilibrium period are multi-recycled through fast reactors and have a different composition. An available TRU fuel composition is determined by fast reactor spent fuel multi-recycling scenarios. Then the FaCT core corresponding to the TRU fuel with different compositions is set according to the TRU fuel composition changes in LWR-to-FBR transition period, and the key core neutronics characteristics are assessed. It is shown that among the core neutronics characteristics, the burnup reactivity and the safety parameters such as sodium void reactivity and Doppler coefficient are significantly influenced by the TRU fuel composition changes. As a result, a general characteristic in the FaCT core design to cope with TRU fuel composition changes is grasped and the design envelopes are identified in terms of the burnup reactivity and the safety parameters. (author)

Chemical Composition of Iran's Pistacia atlantica Cold-Pressed Oil

Directory of Open Access Journals (Sweden)

M. Saber-Tehrani

2013-01-01

Full Text Available The lipid fraction of Pistacia atlantica seeds was extracted for the first time by means of cold-press technique and analyzed for its chemical composition. The fatty acids, sterols, triacylglycerols (TAG, tocopherols, polyphenols, and pigments were identified and their concentrations were determined by means of reversed-phase high-performance liquid chromatography (RP-HPLC and gas chromatography (GC. Because of its high content of unsaturated fatty acids, it might prove to be of value in diets and it may be used as edible cooking or salad oils or for margarine manufacture. Pistacia atlantica seed oil has the unique sterols and tocopherols content providing source of natural antioxidants. The main triacylglycerols were SLL + PLO, SOL + POO, OOLn + PLL, OOO, and SOO. This paper examined the phenolic fraction of Pistacia atlantica seed oil. Moreover, caffeic acid followed by cinnamic acid, pinoresinol, vanillin, p-Coumaric acid, ferulic acid, and o-Coumaric acid was also determined. This paper presents the first investigation of chlorophyll's and carotene's composition in Pistacia atlantica seed oil. Furthermore, pheophytin a was the major component, followed by luteoxanthin, neoxanthin, violaxanthin, lutein, lutein isomers, chlorophyll a, chlorophyll a′, and pheophytin a′ were also determined.

Vitrification of HLW produced by uranium/molybdenum fuel reprocessing in cogema's cold crucible melter

International Nuclear Information System (INIS)

Quang, R. Do; Petitjean, V.; Hollebeque, F.; Pinet, O.; Flament, T.; Prodhomme, A.; Dalcorso, J. P.

2003-01-01

The performance of the vitrification process currently used in the La Hague commercial reprocessing plants has been continuously improved during more than ten years of operation. In parallel COGEMA (industrial Operator), the French Atomic Energy Commission (CEA) and SGN (respectively COGEMA's R and D provider and Engineering) have developed the cold crucible melter vitrification technology to obtain greater operating flexibility, increased plant availability and further reduction of secondary waste generated during operations. The cold crucible is a compact water-cooled melter in which the radioactive waste and the glass additives are melted by direct high frequency induction. The cooling of the melter produces a solidified glass layer that protects the melter's inner wall from corrosion. Because the heat is transferred directly to the melt, high operating temperatures can be achieved with no impact on the melter itself. COGEMA plans to implement the cold crucible technology to vitrify high level liquid waste from reprocessed spent U-Mo-Sn-Al fuel (used in gas cooled reactor). The cold crucible was selected for the vitrification of this particularly hard-to-process waste stream because it could not be reasonably processed in the standard hot induction melters currently used at the La Hague vitrification facilities : the waste has a high molybdenum content which makes it very corrosive and also requires a special high temperature glass formulation to obtain sufficiently high waste loading factors (12% in molybdenum). A special glass formulation has been developed by the CEA and has been qualified through lab and pilot testing to meet standard waste acceptance criteria for final disposal of the U-Mo waste. The process and the associated technologies have been also being qualified on a full-scale prototype at the CEA pilot facility in Marcoule. Engineering study has been integrated in parallel in order to take into account that the Cold Crucible should be installed

Vitrification of HLW Produced by Uranium/Molybdenum Fuel Reprocessing in COGEMA's Cold Crucible Melter

International Nuclear Information System (INIS)

Do Quang, R.; Petitjean, V.; Hollebecque, F.; Pinet, O.; Flament, T.; Prod'homme, A.

2003-01-01

The performance of the vitrification process currently used in the La Hague commercial reprocessing plants has been continuously improved during more than ten years of operation. In parallel COGEMA (industrial Operator), the French Atomic Energy Commission (CEA) and SGN (respectively COGEMA's R and D provider and Engineering) have developed the cold crucible melter vitrification technology to obtain greater operating flexibility, increased plant availability and further reduction of secondary waste generated during operations. The cold crucible is a compact water-cooled melter in which the radioactive waste and the glass additives are melted by direct high frequency induction. The cooling of the melter produces a solidified glass layer that protects the melter's inner wall from corrosion. Because the heat is transferred directly to the melt, high operating temperatures can be achieved with no impact on the melter itself. COGEMA plans to implement the cold crucible technology to vitrify high level liquid waste from reprocessed spent U-Mo-Sn-Al fuel (used in gas cooled reactor). The cold crucible was selected for the vitrification of this particularly hard-to-process waste stream because it could not be reasonably processed in the standard hot induction melters currently used at the La Hague vitrification facilities : the waste has a high molybdenum content which makes it very corrosive and also requires a special high temperature glass formulation to obtain sufficiently high waste loading factors (12 % in molybdenum). A special glass formulation has been developed by the CEA and has been qualified through lab and pilot testing to meet standard waste acceptance criteria for final disposal of the U-Mo waste. The process and the associated technologies have been also being qualified on a full-scale prototype at the CEA pilot facility in Marcoule. Engineering study has been integrated in parallel in order to take into account that the Cold Crucible should be installed

Solid recovered fuel: influence of waste stream composition and processing on chlorine content and fuel quality.

Science.gov (United States)

Velis, Costas; Wagland, Stuart; Longhurst, Phil; Robson, Bryce; Sinfield, Keith; Wise, Stephen; Pollard, Simon

2012-02-07

Solid recovered fuel (SRF) produced by mechanical-biological treatment (MBT) of municipal waste can replace fossil fuels, being a CO(2)-neutral, affordable, and alternative energy source. SRF application is limited by low confidence in quality. We present results for key SRF properties centered on the issue of chlorine content. A detailed investigation involved sampling, statistical analysis, reconstruction of composition, and modeling of SRF properties. The total chlorine median for a typical plant during summer operation was 0.69% w/w(d), with lower/upper 95% confidence intervals of 0.60% w/w(d) and 0.74% w/w(d) (class 3 of CEN Cl indicator). The average total chlorine can be simulated, using a reconciled SRF composition before shredding to limit for ash content marginally below the 20% w/w(d) deemed suitable for certain power plants; and a lower 95% confidence limit of net calorific value (NCV) at 14.5 MJ kg(ar)(-1). The data provide, for the first time, a high level of confidence on the effects of SRF composition on its chlorine content, illustrating interrelationships with other fuel properties. The findings presented here allow rational debate on achievable vs desirable MBT-derived SRF quality, informing the development of realistic SRF quality specifications, through modeling exercises, needed for effective thermal recovery.

Isotopic composition and radiological properties of uranium in selected fuel cycles

International Nuclear Information System (INIS)

Fleischman, R.M.; Liikala, R.C.

1975-04-01

Three major topic areas are discussed: First, the properties of the uranium isotopes are defined relative to their respective roles in the nuclear fuel cycle. Secondly, the most predominant fuel cycles expected in the U. S. are described. These are the Light Water Reactor (LWR), High Temperature Gas Cooled Reactor (HTGR), and Liquid Metal Fast Breeder Reactor (LMFBR) fuel cycles. The isotopic compositions of uranium and plutonium fuels expected for these fuel cycles are given in some detail. Finally the various waste streams from these fuel cycles are discussed in terms of their relative toxicity. Emphasis is given to the high level waste streams from reprocessing of spent fuel. Wastes from the various fuel cycles are compared based on projected growth patterns for nuclear power and its various components. (U.S.)

Lanthanum gallate and ceria composite as electrolyte for solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Li Shuai, E-mail: shuail@kth.s [Department of Materials Science and Engineering, School of Industrial Engineering and Management, Royal Institute of Technology, SE 10044 Stockholm (Sweden); Li Zhicheng [School of Materials Science and Engineering, Central South University, 410083 Changsha, Hunan (China); Bergman, Bill [Department of Materials Science and Engineering, School of Industrial Engineering and Management, Royal Institute of Technology, SE 10044 Stockholm (Sweden)

2010-03-04

The composite of doped lanthanum gallate (La{sub 0.9}Sr{sub 0.1}Ga{sub 0.8}Mg{sub 0.2}O{sub 2.85}, LSGM) and doped ceria (Ce{sub 0.8}Sm{sub 0.2}O{sub 1.9}, CSO) was investigated as an electrolyte for solid oxide fuel cell (SOFC). The LSGM-CSO composite was examined by X-ray diffraction (XRD) and impedance spectroscopy. It was found that the sintered LSGM-CSO composite contains mainly fluorite CeO{sub 2} phase and a minority impurity phase, Sm{sub 3}Ga{sub 5}O{sub 12}. The LSGM-CSO composite electrolyte shows a small grain boundary response in the impedance spectroscopy as compared to LSGM and CSO pellets. The composite electrolyte exhibits the highest conductivity in the temperature range of 250-600 {sup o}C, compared to LSGM and CSO. The LSGM-CSO composite can be expected to be an attractive intermediate temperature electrolyte material for solid oxide fuel cells.

Parametric studies on the fuel salt composition in thermal molten salt breeder reactors

International Nuclear Information System (INIS)

Nagy, K.; Kloosterman, J.L.; Lathouwers, D.; Van der Hagen, T.H.J.J.

2008-01-01

In this paper the salt composition and the fuel cycle of a graphite moderated molten salt self-breeder reactor operating on the thorium cycle is investigated. A breeder molten salt reactor is always coupled to a fuel processing plant which removes the fission products and actinides from the core. The efficiency of the removal process(es) has a large influence on the breeding capacity of the reactor. The aim is to investigate the effect on the breeding ratio of several parameters such as the composition of the molten salt, moderation ratio, power density and chemical processing. Several fuel processing strategies are studied. (authors)

Effect of Impact Angle on Ceramic Deposition Behavior in Composite Cold Spray: A Finite-Element Study

Science.gov (United States)

Chakrabarty, Rohan; Song, Jun

2017-10-01

During the cold spraying of particle-reinforced metal matrix composite coatings (ceramic and metal particles mixture) on metal substrates, ceramic particles may either get embedded in the substrate/deposited coating or may rebound from the substrate surface. In this study, the dependence of the ceramic rebounding phenomenon on the spray angle and its effect on substrate erosion have been analyzed using finite-element analysis. From the numerical simulations, it was found that the ceramic particle density and substrate material strength played the major roles in determining the embedding and ceramic retention behavior. Substrate material erosion also influenced the ceramic retention, and the material loss increased as the impact angles decreased from normal. In general, the results concluded that decreasing the impact angle promoted the retention possibility of ceramics in the substrate. This study provides new theoretical insights into the effect of spray angles on the ceramic retention and suggests a new route toward optimizing the spraying process to increase the ceramic retention in composite coatings cold spray.

Fuel containment and damage tolerance for large composite primary aircraft structures. Phase 1: Testing

Science.gov (United States)

Sandifer, J. P.

1983-01-01

Technical problems associated with fuel containment and damage tolerance of composite material wings for transport aircraft were identified. The major tasks are the following: (1) the preliminary design of damage tolerant wing surface using composite materials; (2) the evaluation of fuel sealing and lightning protection methods for a composite material wing; and (3) an experimental investigation of the damage tolerant characteristics of toughened resin graphite/epoxy materials. The test results, the test techniques, and the test data are presented.

High Time Resolution Measurements of VOCs from Vehicle Cold Starts: The Air Toxic Cold Start Pulse

Science.gov (United States)

Jobson, B. T.; Huangfu, Y.; Vanderschelden, G. S.

2017-12-01

Pollutants emitted during motor vehicle cold starts, especially in winter in some climates, is a significant source of winter time air pollution. While data exist for CO, NO, and total hydrocarbon emissions from federal testing procedures for vehicle emission certification, little is known about the emission rates of individual volatile organic compounds, in particular the air toxics benzene, formaldehyde, and acetaldehyde. Little is known about the VOC speciation and temperature dependence for cold starts. The US EPA vehicle emission model MOVES assumes that cold start emissions have the same speciation profile as running emissions. We examined this assumption by measuring cold start exhaust composition for 4 vehicles fueled with E10 gasoline over a temperature range of -4°C to 10°C in winter of 2015. The extra cold start emissions were determined by comparison with emissions during engine idling. In addition to CO and NOx measurements a proton transfer reaction mass spectrometer was used to measure formaldehyde, acetaldehyde, benzene, toluene, and C2-alkylbenzenes at high time resolution to compare with the cold start emission speciation profiles used in the EPA MOVES2014 model. The results show that after the vehicle was started, CO mixing ratios can reach a few percent of the exhaust and then drop to several ppmv within 2 minutes of idling, while NOx showed different temporal behaviors among the four vehicles. VOCs displayed elevated levels during cold start and the peak mixing ratios can be two orders higher than idling phase levels. Molar emission ratios relative to toluene were used to compare with the emission ratio used in MOVES2014 and we found the formaldehyde-to-toluene emission ratio was about 0.19, which is 5 times higher than the emission ratio used in MOVES2014 and the acetaldehyde-to-toluene emission ratios were 0.86-0.89, which is 8 times higher than the ones in MOVES2014. The C2-alkylbenzene-to-toluene ratio agreed well with moves. Our results

Critical firing and misfiring boundary in a spark ignition methanol engine during cold start based on single cycle fuel injection

International Nuclear Information System (INIS)

Li, Zhaohui; Gong, Changming; Qu, Xiang; Liu, Fenghua; Sun, Jingzhen; Wang, Kang; Li, Yufeng

2015-01-01

The influence of the mass of methanol injected per cycle, ambient temperature, injection and ignition timing, preheating methods, and supplying additional liquefied petroleum gas (LPG) injection into the intake manifold on the critical firing and misfiring boundary of an electronically injection controlled spark ignition (SI) methanol engine during cold start were investigated experimentally based on a single cycle fuel injection with cycle-by-cycle control strategy. The critical firing and misfiring boundary was restricted by all parameters. For ambient temperatures below 16 °C, methanol engines must use auxiliary start-aids during cold start. Optimal control of the methanol injection and ignition timing can realize ideal next cycle firing combustion after injection. Resistance wire and glow plug preheating can provide critical firing down to ambient temperatures of 5 °C and 0 °C, respectively. Using an additional LPG injection into the intake manifold can provide critical firing down to an ambient temperature of −13 °C during cold start. As the ambient temperature decreases, the optimal angle difference between methanol injection timing and LPG injection timing for critical firing of a methanol engine increases rapidly during cold start. - Highlights: • A single cycle fuel injection and cycle-by-cycle control strategy are used to study. • In-cylinder pressure and instantaneous speed were used to determine firing boundary. • For the ambient temperatures below 16 °C, an auxiliary start-aids must be used. • A preheating and additional LPG were used to expand critical firing boundary. • Additional LPG can result in critical firing down to ambient temperature of −13 °C

Altered Microbiota Contributes to Reduced Diet-Induced Obesity upon Cold Exposure

DEFF Research Database (Denmark)

Ziętak, Marika; Kovatcheva-Datchary, Petia; Markiewicz, Lidia H

2016-01-01

Maintenance of body temperature in cold-exposed animals requires induction of thermogenesis and management of fuel. Here, we demonstrated that reducing ambient temperature attenuated diet-induced obesity (DIO), which was associated with increased iBAT thermogenesis and a plasma bile acid profile...... similar to that of germ-free mice. We observed a marked shift in the microbiome composition at the phylum and family levels within 1 day of acute cold exposure and after 4 weeks at 12°C. Gut microbiota was characterized by increased levels of Adlercreutzia, Mogibacteriaceae, Ruminococcaceae......, and Desulfovibrio and reduced levels of Bacilli, Erysipelotrichaceae, and the genus rc4-4. These genera have been associated with leanness and obesity, respectively. Germ-free mice fed a high-fat diet at room temperature gained less adiposity and improved glucose tolerance when transplanted with caecal microbiota...

Experimental Assessment of the Mass of Ash Residue During the Burning of Droplets of a Composite Liquid Fuel

Science.gov (United States)

Glushkov, D. O.; Zakharevich, A. V.; Strizhak, P. A.; Syrodoi, S. V.

2018-05-01

An experimental study has been made of the regularities of burning of single droplets of typical compositions of a composite liquid fuel during the heating by an air flow with a varied temperature (600-900 K). As the basic components of the compositions of the composite liquid fuel, use was made of the: waste of processing (filter cakes) of bituminous coals of ranks K, C, and T, waste motor, turbine, and transformer oils, process mixture of mazut and oil, heavy crude, and plasticizer. The weight fraction of a liquid combustible component (petroleum) product) ranged within 0-15%. Consideration has been given to droplets of a composite liquid fuel with dimensions (radius) of 0.5 to 2 mm. Conditions of low-temperature initiation of combustion to ensure a minimum possible mass of solid incombustible residue have been determined. Petroleum products have been singled out whose addition to the composition of the composite liquid fuel tends to increase the ash mass (compared to the corresponding composition without a liquid combustible component). Approximation dependences have been obtained which permit predicting the influence of the concentration of the liquid petroleum product as part of the composite liquid fuel on the ash-residue mass.

Cold laser machining of nickel-yttrium stabilised zirconia cermets: Composition dependence

International Nuclear Information System (INIS)

Sola, D.; Gurauskis, J.; Pena, J.I.; Orera, V.M.

2009-01-01

Cold laser micromachining efficiency in nickel-yttrium stabilised zirconia cermets was studied as a function of cermet composition. Nickel oxide-yttrium stabilised zirconia ceramic plates obtained via tape casting technique were machined using 8-25 ns pulses of a Nd: YAG laser at the fixed wavelength of 1.064 μm and a frequency of 1 kHz. The morphology of the holes, etched volume, drill diameter, shape and depth were evaluated as a function of the processing parameters such as pulse irradiance and of the initial composition. The laser drilling mechanism was evaluated in terms of laser-material interaction parameters such as beam absorptivity, material spallation and the impact on the overall process discussed. By varying the nickel oxide content of the composite the optical absorption (-value is greatly modified and significantly affected the drilling efficiency of the green state ceramic substrates and the morphology of the holes. Higher depth values and improved drilled volume upto 0.2 mm 3 per pulse were obtained for substrates with higher optical transparency (lower optical absorption value). In addition, a laser beam self-focussing effect is observed for the compositions with less nickel oxide content. Holes with average diameter from 60 μm to 110 μm and upto 1 mm in depth were drilled with a high rate of 40 ms per hole while the final microstructure of the cermet obtained by reduction of the nickel oxide-yttrium stabilised zirconia composites remained unchanged.

Nafion®/H-ZSM-5 composite membranes with superior performance for direct methanol fuel cells

NARCIS (Netherlands)

Yildirim, M.H.; Curos, Anna Roca; Motuzas, Julius; Motuzas, J.; Julbe, Anne; Stamatialis, Dimitrios; Wessling, Matthias

2009-01-01

Solution cast composite direct methanol fuel cell membranes (DEZ) based on DE2020 Nafion® dispersion and in-house prepared H-ZSM-5 zeolites with different Si/Al ratios were prepared and thoroughly characterized for direct methanol fuel cell (DMFC) applications. All composite membranes have indeed

Structural aspects of cold-formed steel section designed as U-shape composite beam

Science.gov (United States)

Saggaff, Anis; Tahir, Mahmood Md.; Azimi, Mohammadamin; Alhajri, T. M.

2017-11-01

Composite beam construction usually associated with old-style Hot-Rolled Steel Section (HRSS) has proven to act much better in compare with Cold-Formed Steel Section (CFSS) sections due to thicker section. Due, it's getting popular to replace HRSS with CFSS in some aspects as a composite beam. The advantages such as lightweight, cost effective and easy to install have contributed to the apply CFSS as a preferred construction material for composite beam. There is a few technical data available regarding the application of the usage of CFSS as a composite system, despite the potentials use for residential and light-weight industrial constructions. This paper presents an experimental tests results which have been conducted using CFSS as composite beam. Composite action of CFSS arranged as double beam with Self-Compacting Concrete (SCC) slab are integrated together with bolted shear connectors were used. A full-scale test comprised of 3 proposed composite beam specimens with bolted shear connector spaced at 300 mm interval of grade 8.8 was using single nut with washer on flange of CFS, cast to the slab and loaded until failed. The test show that the bolted shear connector yielded better capacity of ultimate strength and ultimate moment for the proposed composite beam. It can be concluded that, bolted shear connectors of 16 mm in diameter performed better than the other diameter size of bolted shear connectors.

The Role of Hydrogen Bonds Of The Azeotropic Hydrous Ethanol Fuel Composition To The Exhaust Emissions

Science.gov (United States)

Made Suarta, I.; Nyoman Gede Baliarta, I.; Sopan Rahtika, I. P. G.; Wijaya Sunu, Putu

2018-01-01

In this study observed the role of hydrogen bonding to the composition of exhaust emissions which is produced hydrous ethanol fuel (95.5% v). Testing is done by using single cylinder four stroke motor engine. The composition of exhaust gas emissions is tested using exhaust gas analyzer on lean and stoichiometry mixer. The exhaust emissions produced by anhydrous ethanol were also tested. The composition of emissions produced by that two fuels is compared. The results showed CO emissions levels produced by hydrous ethanol are slightly higher than anhydrous ethanol in stoichiometric mixtures. But the composition of CO hydrous ethanol emissions is lower in the lean mix. If lean the mixer the different in the composition of emissions is increasing. On hydrous ethanol emission CO2 content little bit lower on the stoichiometric mixer and higher on the lean mixture. Exhaust emissions of ethanol fuel also produce O2. O2 hydrous ethanol emissions is higher than anhydrous ethanol fuel.

Chemical composition and source of fine and nanoparticles from recent direct injection gasoline passenger cars: Effects of fuel and ambient temperature

Science.gov (United States)

Fushimi, Akihiro; Kondo, Yoshinori; Kobayashi, Shinji; Fujitani, Yuji; Saitoh, Katsumi; Takami, Akinori; Tanabe, Kiyoshi

2016-01-01

Particle number, mass, and chemical compositions (i.e., elemental carbon (EC), organic carbon (OC), elements, ions, and organic species) of fine particles emitted from four of the recent direct injection spark ignition (DISI) gasoline passenger cars and a port fuel injection (PFI) gasoline passenger car were measured under Japanese official transient mode (JC08 mode). Total carbon (TC = EC + OC) dominated the particulate mass (90% on average). EC dominated the TC for both hot and cold start conditions. The EC/TC ratios were 0.72 for PFI and 0.88-1.0 (average = 0.92) for DISI vehicles. A size-resolved chemical analysis of a DISI car revealed that the major organic components were the C20-C28 hydrocarbons for both the accumulation-mode particles and nanoparticles. Contribution of engine oil was estimated to be 10-30% for organics and the sum of the measured elements. The remaining major fraction likely originated from gasoline fuel. Therefore, it is suggested that soot (EC) also mainly originated from the gasoline. In experiments using four fuels at three ambient temperatures, the emission factors of particulate mass were consistently higher with regular gasoline than with premium gasoline. This result suggest that the high content of less-volatile compounds in fuel increase particulate emissions. These results suggest that focusing on reducing fuel-derived EC in the production process of new cars would effectively reduce particulate emission from DISI cars.

Solid oxide fuel cell having a glass composite seal

Science.gov (United States)

De Rose, Anthony J.; Mukerjee, Subhasish; Haltiner, Jr., Karl Jacob

2013-04-16

A solid oxide fuel cell stack having a plurality of cassettes and a glass composite seal disposed between the sealing surfaces of adjacent cassettes, thereby joining the cassettes and providing a hermetic seal therebetween. The glass composite seal includes an alkaline earth aluminosilicate (AEAS) glass disposed about a viscous glass such that the AEAS glass retains the viscous glass in a predetermined position between the first and second sealing surfaces. The AEAS glass provides geometric stability to the glass composite seal to maintain the proper distance between the adjacent cassettes while the viscous glass provides for a compliant and self-healing seal. The glass composite seal may include fibers, powders, and/or beads of zirconium oxide, aluminum oxide, yttria-stabilized zirconia (YSZ), or mixtures thereof, to enhance the desirable properties of the glass composite seal.

Copper-substituted perovskite compositions for solid oxide fuel cell cathodes and oxygen reduction electrodes in other electrochemical devices

Science.gov (United States)

Rieke, Peter C [Pasco, WA; Coffey, Gregory W [Richland, WA; Pederson, Larry R [Kennewick, WA; Marina, Olga A [Richland, WA; Hardy, John S [Richland, WA; Singh, Prabhaker [Richland, WA; Thomsen, Edwin C [Richland, WA

2010-07-20

The present invention provides novel compositions that find advantageous use in making electrodes for electrochemical cells. Also provided are electrochemical devices that include active oxygen reduction electrodes, such as solid oxide fuel cells, sensors, pumps and the like. The compositions comprises a copper-substituted ferrite perovskite material. The invention also provides novel methods for making and using the electrode compositions and solid oxide fuel cells and solid oxide fuel cell assemblies having cathodes comprising the compositions.

Clean fuel-magnesia bonded coal briquetting

Energy Technology Data Exchange (ETDEWEB)

Tosun, Yildirim I. [S. Demirel University Eng., Arch. Faculty Mining Eng. Department, Isparta (Turkey)

2007-10-15

Benefaction from coal fines as solid fuel in Turkey is very much important for economical development. Beneficiation from washed coal fines in the industry using solid fuel at lump size and in the municipal areas as an household solid fuel may be only provided by hot briquetting of the coal fines. The most practical common way of that benefication from coal fines in our country have been hot binding by sulfite liquor-sulfite liquor-melas and lime mixtures. Harmful the flue content of sulfite liquor-melas may only be eliminated by lime, a type of solid additive. However, cold bonded briquettes produced from coal fines are environmentally free. Just ash contents of these briquettes increase at a certain degree and heat content of them decrease at a certain extent. By using magnesia binder showed in this study, Tuncbilek lignite fines have been briquetted by cold and hot briquetting techniques. The qualities of briquettes produced by cold binders were compared with to those produced by other hot binding methods As a result, magnesia binder showed the similar characteristics with those of the briquettes produced by only cold bonded gypsum. Use of magnesite mixture and gypsum just as only cold binder was not suitable for the requirements from the coal briquettes to be used as solid fuels, particularly from household fuels, but just only as cold additive should be used. (author)

Coriander seed oil methyl esters as biodiesel fuel: Unique fatty acid composition and excellent oxidative stability

International Nuclear Information System (INIS)

Moser, Bryan R.; Vaughn, Steven F.

2010-01-01

Coriander (Coriandrum sativum L.) seed oil methyl esters were prepared and evaluated as an alternative biodiesel fuel and contained an unusual fatty acid hitherto unreported as the principle component in biodiesel fuels: petroselinic (6Z-octadecenoic; 68.5 wt%) acid. Most of the remaining fatty acid profile consisted of common 18 carbon constituents such as linoleic (9Z,12Z-octadeca-dienoic; 13.0 wt%), oleic (9Z-octadecenoic; 7.6 wt%) and stearic (octadecanoic; 3.1 wt%) acids. A standard transesterification procedure with methanol and sodium methoxide catalyst was used to provide C. sativum oil methyl esters (CSME). Acid-catalyzed pretreatment was necessary beforehand to reduce the acid value of the oil from 2.66 to 0.47 mg g -1 . The derived cetane number, kinematic viscosity, and oxidative stability (Rancimat method) of CSME was 53.3, 4.21 mm 2 s -1 (40 o C), and 14.6 h (110 o C). The cold filter plugging and pour points were -15 o C and -19 o C, respectively. Other properties such as acid value, free and total glycerol content, iodine value, as well as sulfur and phosphorous contents were acceptable according to the biodiesel standards ASTM D6751 and EN 14214. Also reported are lubricity, heat of combustion, and Gardner color, along with a comparison of CSME to soybean oil methyl esters (SME). CSME exhibited higher oxidative stability, superior low temperature properties, and lower iodine value than SME. In summary, CSME has excellent fuel properties as a result of its unique fatty acid composition.

Effects of microwave roasting on the yield and composition of cold pressed orange seed oils

International Nuclear Information System (INIS)

Aydeniz Güneşer, B.; Yilmaz, E.

2017-01-01

The aim of this study was to valorize orange (Citrus sinensis) seeds, which are generated as waste. This study presents data about raw orange seed, the meal gained after cold pressing, and characterization data of the cold pressed seed oils. Furthermore, the effects of microwave roasting of the seds compared to regular roasting (control) were determined. The oil yield of orange seed cold pressing was around 52.93–62.99%. After cold pressing, 13.57–17.97% oil remained in the meal together with 20.68–25.61% protein. Hence, pressed meals could be valorized for different purposes. Except for turbidity, the color b* value, free acidity, the p-anisidine value and antioxidant capacity, there was no significant difference between the two oil samples for the measured physicochemical properties. Six different fatty acids were quantified and the major fatty acids were linoleic, palmitic and oleic acids. The fatty acid composition of the orange seed oil can be accepted as nutritionally balanced. Among the fifteen sterols quantified, β-sitosterol was dominant (around 77–78%). Likewise, the α-tocopherol content of the samples was not significantly different. The thermal onset and peak temperatures, and enthalpies for crystallization and melting were also reported. This study showed that good quality orange seed oils can be produced by cold pressing, and the oils could be used in food and non-food applications. [es

Evaluation of core compositions for use in breed and burn reactors and limited-separations fuel cycles

International Nuclear Information System (INIS)

Petroski, Robert; Forget, Benoit; Forsberg, Charles

2013-01-01

Highlights: ► Calculated minimum burnup and irradiation damage for B and B reactor compositions. ► Computed doubling time of fuel cycles using B and B reactors and no chemical separations. ► Determined sensitivity of doubling time to using melt refining vs. direct reuse. ► Examined tradeoff between power density and neutronics for different coolants. - Abstract: Previously developed methods for analyzing breed-and-burn (B and B) reactors are applied to a wide range of core compositions. The compositions studied include different fuel types, steel and silicon carbide structure, and sodium, lead/lead bismuth eutectic (LBE), and gas coolants. These compositions are evaluated for use in “minimum burnup” B and B reactors in which it is assumed that blocks comprising the core can be shuffled in all three dimensions to flatten out non-uniformities in burnup. The two figures of merit evaluated are the minimum irradiation damage requirement and reactor fleet doubling time. To minimize irradiation damage, gas coolants perform best, followed by lead/LBE then sodium. High uranium-content metal fuel outperforms compound fuels, and different types of steel are similar and perform slightly better than silicon carbide. Once-through irradiation damage requirements can be surprisingly modest in minimum burnup B and B reactors, with a wide range of compositions viable at irradiation damage levels 50% higher than existing materials data. Doubling times were calculated for a reactor fleet consisting of B and B reactors operating in a limited-separations fuel cycle; i.e., a fuel cycle with no chemical separation of actinides. The effects of different cooling times and removal of fission products using a melt refining process are evaluated. To minimize doubling time, sodium cooled compositions perform best because they are able to achieve core power densities several times larger than compositions using other coolants. A hypothetical sodium-cooled core composition with high

Development of nondestructive measurement of cold work rate, (2)

International Nuclear Information System (INIS)

Kamimura, Hideaki; Igarashi, Miyuki; Satoh, Masakazu; Miura, Makoto

1978-01-01

Cold-worked type 316 stainless steel will be used as fuel cladding material for the proto-type fast reactor MONJU. Cold work rate is an important parameter in swelling behavior of fuel cladding. It has been shown that austenitic stainless steel undergoes martensitic transformation during cold working. Nondestructive evaluation of cold work rate will be expected by measuring residual magnetism produced in the presence of martensitic phase when cold worked austenitic stainless steel is magnetized. In the previous work, the residual magnetism of cladding tubes of type 316 stainless steel was measured. The results have shown high degree of the correlation between residual magnetism and cold work rate. This paper reports the results of measurement on cold-rolled type 316 stainless steel plate samples. Dimensions of the specimens are 100 mm long and 3.5 and 7 mm wide. The apparatus and experimental procedures were similar to the previous work. Good agreement was found between the estimated cold work rate obtained in the previous work and that for cold rolled plate specimens. Measurement of residual magnetism in identical direction with magnetization showed smaller dispersion of data as compared with that in transverse direction. The residual magnetism near specimen surface hardly decreased when the surface of specimen was chemically removed. The reason for the comparative decrease in residual magnetism at 10% and 15% cold work rate is not clear. (Wakatsuki, Y.)

EFFECT OF COMPOSITION OF FUEL CONTAINING BUTANOL ON WORKING PROCESS PARAMETERS OF DIESEL ENGINE

Directory of Open Access Journals (Sweden)

D. G. Hershan

2017-01-01

Full Text Available Computational researches the effect of composition of fuel containing butanol on working process parameters of 4ЧН 11/12,5 diesel engine on the external speed characteristic have been conducted. Nominal power is 140 kW at engine speed 2300 min–1. The engine is equipped with gas turbine pressure charging with intercooling of charging air, accumulator-type fuel-handling system. Calculations of the working process have been made in accordance with the developed computer program and models. Investigations have been carried out in two stages: without any changes in regulation of fuel-handling system and with cyclic fuel delivery that ensure such value of excess air factor at various operational modes which corresponds to the operation with diesel fuel. All the obtained results have been analyzed in the paper. The paper shows changes in mean indicated pressure, specific indicated fuel consumption, indicated efficiency, specific nitrogen oxides emissions for various modes in question while using 5, 10, 15, 20, 25 and 30 % mixture of diesel fuel with butanol. Dependences of parameters pertaining to diesel operation have been determined according to external speed characteristic for various mixtures and the obtained data make it possible to justify parameters of the fuel-handling system. It has been recommended to use a diesel fuel-butanol mixture containing 15 % of butanol without any changes in regulating and design engine parameters. It has been revealed that in order to improve parameters of the engine operational process mixture composition must be changed while changing the operational mode. An injector nozzle with a compound needle for the fuel-handling system has been developed and it allows to change fuel composition according to engine operational mode.

Systematic Approach to Design Tailor Made Fuel Blends That Meets ASTM Standards

DEFF Research Database (Denmark)

Intikhab, S.; Kalakul, Sawitree; H., Choudhury

2015-01-01

point, vapor pressure, and heat content were determined using analytical instruments according to their respective American Society for Testing and Materials (ASTM) standards. Most of the properties complied well with the industry standards. However, model gasoline had a comparatively low RVP....... On the other hand, model diesel had a significantly higher cloud point and pour point than what is recommended. This deviation will have an impact on the cold flow properties of the fuels. For both fuels, different additives along with their composition have also been determined using the same computational...

Heat and cold accumulators in vehicles

Energy Technology Data Exchange (ETDEWEB)

Kauranen, P.; Wikstroem, L. (VTT Technical Research Centre of Finland, Advanced Materials, Tampere (Finland)); Heikkinen, J. (VTT Technical Research Centre of Finland, Building Services and Indoor Environment, Espoo (Finland)); Laurikko, J.; Elonen, T. (VTT Technical Research Centre of Finland, Emission Control, Espoo (Finland)); Seppaelae, A. (Helsinki Univ. of Technology, Applied Thermodynamics, Espoo (Finland)). Email: ari.seppala@tkk.fi

2009-07-01

Phase Change Material (PCM) based heat and cold accumulators have been tailored for transport applications including a mail delivery van as well as the cold chains of foodstuff and blood products. The PCMs can store relative large amount of thermal energy in a narrow temperature interval as latent heat of fusion of their melting and crystallization processes. Compact heat and cold accumulators can be designed using PCMs. The aim of the project has been to reduce the exhaust gas and noise emissions and improve the fuel economy of the transport systems and to improve the reliability of the cold chains studied by storing thermal energy in PCM accumulators. (orig.)

Changes in Cuticular Wax Composition of Two Blueberry Cultivars during Fruit Ripening and Postharvest Cold Storage.

Science.gov (United States)

Chu, Wenjing; Gao, Haiyan; Chen, Hangjun; Wu, Weijie; Fang, Xiangjun

2018-03-21

Cuticular wax plays an important role for the quality of blueberry fruits. In this study, the cuticular wax composition of two blueberry cultivars, 'Legacy' ( Vaccinium corymbosum) and 'Brightwell' ( Vaccinium ashei), was examined during fruit ripening and postharvest cold storage. The results showed that wax was gradually deposited on the epidermis of blueberry fruits and the content of major wax compounds, except that for diketones, increased significantly during fruit ripening. The total wax content was 2-fold greater in 'Brightwell' blueberries than that in 'Legacy' blueberries during fruit ripening. The total wax content of both cultivars decreased during 30 days of storage at 4 °C, and the variation of cuticular wax composition was cultivar-dependent. The content of diketones decreased significantly in 'Legacy' blueberries, while the content of triterpenoids and aliphatic compounds showed different fold changes in 'Brightwell' blueberries after 30 days of storage at 4 °C. Overall, our study provided a quantitative and qualitative overview of cuticular wax compounds of blueberry fruits during ripening and postharvest cold storage.

A cold demonstration of fuel consolidation. Part 1

International Nuclear Information System (INIS)

Matheson, J.E.

1989-01-01

Spent fuel consolidation is an option for increasing spent fuel storage capacities being considered by many utilities. The process of consolidating fuel involves separating the fuel rods from the structural frame which holds them in a square array. The rods are then repackaged into a tightly packed bundle which occupies about half the cross-sectional area of fuel assembly. Thus approximately twice as much fuel can be stored in the underwater racks at a spent fuel storage pool. There have been several demonstrations of fuel consolidation to date. The focus of this paper is the development and subsequent demonstration program of a shear/compactor

Cobalt oxide-based catalysts deposited by cold plasma for proton exchange membrane fuel cells

Energy Technology Data Exchange (ETDEWEB)

Kazimierski, P.; Jozwiak, L.; Sielski, J.; Tyczkowski, J., E-mail: jacek.tyczkowski@p.lodz.pl

2015-11-02

In proton exchange membrane fuel cells (PEMFC), both the anodic hydrogen oxidation reaction and the cathodic oxygen reduction reaction (ORR) require appropriate catalysts. So far, platinum-based catalysts are still the best option for this purpose. However, because these catalysts are too expensive for making commercially viable fuel cells, extensive research over the past decade has focused on developing noble metal-free alternative catalysts. In this paper, an approach based on cobalt oxide films fabricated by plasma-enhanced metal-organic chemical vapor deposition is presented. Such a material can be used to prepare catalysts for ORR in PEMFC. The films containing CoO{sub X} were deposited on a carbon paper thereby forming the electrode. Morphology and atomic composition of the films were investigated by scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively. The possibility of their application as the electro-catalyst for ORR in PEMFC was investigated and the electro-catalytic activities were evaluated by the electrochemical measurements and single cell tests. It was found that the fuel cell with Pt as the anode catalyst and CoO{sub X} deposit as the cathode catalyst was characterized by the open circuit voltage of 635 mV, Tafel slope of approx. 130 mV/dec and the maximum power density of 5.3 W/m{sup 2}. - Highlights: • Cobalt oxide catalyst for proton exchange membrane fuel cells was plasma deposited. • The catalyst exhibits activity for the oxygen reduction reaction. • Morphology and atomic composition of the catalyst were determined.

Low - temperature properties of rape seed oil biodiesel fuel and its blending with other diesel fuels

International Nuclear Information System (INIS)

Kampars, V.; Skujins, A.

2004-01-01

The properties of commercial bio diesel fuel depend upon the refining technique and the nature of the renewable lipids from which it is produced. The examined bio diesel fuel produced from rape seed oil by the Latvian SIA 'Delta Riga' has better low-temperature properties than many other bio diesels; but a considerably higher cloud point (-5,7 deg C), cold filter plugging point (-7 deg C) and pour point (-12 deg C) than the examined petrodiesel (grade C, LST EN 590:2000) from AB 'Mazeikiu nafta'. The low-temperature properties considerably improve if blending of these fuels is used. The blended fuels with bio diesel contents up to 90% have lower cold filter plugging points than petrodollar's. The estimated viscosity variations with temperature show that the blended fuels are Arrenius-type liquids, which lose this property near the cold filter plugging point. (authors)

Cold vacuum drying facility design requirements

Energy Technology Data Exchange (ETDEWEB)

IRWIN, J.J.

1999-07-01

This document provides the detailed design requirements for the Spent Nuclear Fuel Project Cold Vacuum Drying Facility. Process, safety, and quality assurance requirements and interfaces are specified.

Cold vacuum drying facility design requirements

International Nuclear Information System (INIS)

IRWIN, J.J.

1999-01-01

This document provides the detailed design requirements for the Spent Nuclear Fuel Project Cold Vacuum Drying Facility. Process, safety, and quality assurance requirements and interfaces are specified

Analysis of the optimal fuel composition for the Indonesian experimental power reactor

Energy Technology Data Exchange (ETDEWEB)

Liem, Peng Hong [Nippon Advanced Information Service (NAIS Co., Inc.), Ibaraki (Japan); Sembiring, Tagor Malem [National Nuclear Energy Agency of Indonesia, Banten (Indonesia). Center for Nuclear Reactor Technology and Safety; Arbie, Bakri; Subki, Iyos [PT MOTAB Technology, Jakarta Barat (Indonesia)

2017-03-15

The optimal fuel composition of the 10 MWth Experimental Power Reactor (RDE), to be built by the Indonesian National Nuclear Energy Agency (BATAN), is a very important design parameter since it will directly affect the fuel cost, new and spent fuel storage capacity, and other back-end environmental burden. The RDE is a very small sized pebble-bed high temperature gas-cooled reactor (HTGR) with low enriched uranium (LEU) UO{sub 2} TRISO fuel under multipass or once-through-then-out fueling scheme. A scoping study on fuel composition parameters, namely heavy metal (HM) loading per pebble and uranium enrichment is conducted. All burnup, criticality calculations and core equilibrium search are carried out by using BATAN-MPASS, a general in-core fuel management code for pebble bed HTGRs, featured with many automatic equilibrium searching options as well as thermal-hydraulic calculation capability. The RDE User Requirement Document issued by BATAN is used to derive the main core design parameters and constraints. The scoping study is conducted over uranium enrichment in the range of 10 to 20 w/o and HM loading in the range of 4 g to 10 g/pebble. Fissile loading per unit energy generated (kg/GWd) is taken as the objective function for the present scoping study. The analysis results show that the optimal HM loading is around 8 g/pebble. Under the constraint of 80 GWd/t fuel discharge burnup imposed by the technical specification, the uranium enrichment for the optimal HM loading is approximately 13 w/o.

Analysis of the optimal fuel composition for the Indonesian experimental power reactor

International Nuclear Information System (INIS)

Liem, Peng Hong; Sembiring, Tagor Malem

2017-01-01

The optimal fuel composition of the 10 MWth Experimental Power Reactor (RDE), to be built by the Indonesian National Nuclear Energy Agency (BATAN), is a very important design parameter since it will directly affect the fuel cost, new and spent fuel storage capacity, and other back-end environmental burden. The RDE is a very small sized pebble-bed high temperature gas-cooled reactor (HTGR) with low enriched uranium (LEU) UO_2 TRISO fuel under multipass or once-through-then-out fueling scheme. A scoping study on fuel composition parameters, namely heavy metal (HM) loading per pebble and uranium enrichment is conducted. All burnup, criticality calculations and core equilibrium search are carried out by using BATAN-MPASS, a general in-core fuel management code for pebble bed HTGRs, featured with many automatic equilibrium searching options as well as thermal-hydraulic calculation capability. The RDE User Requirement Document issued by BATAN is used to derive the main core design parameters and constraints. The scoping study is conducted over uranium enrichment in the range of 10 to 20 w/o and HM loading in the range of 4 g to 10 g/pebble. Fissile loading per unit energy generated (kg/GWd) is taken as the objective function for the present scoping study. The analysis results show that the optimal HM loading is around 8 g/pebble. Under the constraint of 80 GWd/t fuel discharge burnup imposed by the technical specification, the uranium enrichment for the optimal HM loading is approximately 13 w/o.

Fuel effects on the stability of turbulent flames with compositionally inhomogeneous inlets

KAUST Repository

Guiberti, T. F.

2016-10-11

This paper reports an analysis of the influence of fuels on the stabilization of turbulent piloted jet flames with inhomogeneous inlets. The burner is identical to that used earlier by the Sydney Group and employs two concentric tubes within the pilot stream. The inner tube, carrying fuel, can be recessed, leading to a varying degree of inhomogeneity in mixing with the outer air stream. Three fuels are tested: dimethyl ether (DME), liquefied petroleum gas (LPG), and compressed natural gas (CNG). It is found that improvement in flame stability at the optimal compositional inhomogeneity is highest for CNG and lowest for DME. Three possible reasons for this different enhancement in stability are investigated: mixing patterns, pilot effects, and fuel chemistry. Numerical simulations realized in the injection tube highlight similarities and differences in the mixing patterns for all three fuels and demonstrate that mixing cannot explain the different stability gains. Changing the heat release rates from the pilot affects the three fuels in similar ways and this also implies that the pilot stream is unlikely to be responsible for the observed differences. Fuel reactivity is identified as a key factor in enhancing stability at some optimal compositional inhomogeneity. This is confirmed by inference from joint images of PLIF-OH and PLIF-CHO, collected at a repetition rate of 10kHz in turbulent flames of DME, and from one-dimensional calculations of laminar flames using detailed chemistry for DME, CNG, and LPG.

Influence of surface modified nanoilmenite/amorphous silica composite particles on the thermal stability of cold galvanizing coating

Directory of Open Access Journals (Sweden)

A.M. Al-Sabagh

2018-03-01

Full Text Available The present approach investigates the use of novel nanoilmenite/amorphous silica composite (NI/AS particles fabricated from ilmenite nanoparticles (FeTiO3 NPs and synthesized amorphous silica grains to improve thermal stability of the cold galvanizing coating. Transmission electron microscopic (TEM images demonstrated that both nanoilmenite and nanocomposite particles were of flaky-like nature and the average diameter of the particles is 20 nm. The lamellar shape of the nanocomposite and spherical nature of Zn-dust particles were illustrated by scanning electron microscopy (SEM micrographs. Different alkyd-based cold galvanizing coating formulations were modified using uniformly dispersing various amounts of the processed nanocomposite particles as a modifier to form some engineering nanocomposite coatings. Thermal stability of the nanocomposite and Zn-dust particles was determined by thermo-gravimetric analysis (TGA. From the obtained results it could be observed that the weight loss (% as a feature of the thermal stability in case of the nanocomposite particles was 2.9 compared to 85.9 for Zn-dust powder grains. Derivative thermo-gravimetric (DTG measurements were done under nitrogen atmosphere for the cured cold galvanizing coating samples heated from room temperature to 1000 °C. The obtained results revealed that the maximum decomposition temperature point in the third degradation step for 6% nanocomposite surface modified cured sample (CG-F was detected at 693 °C and was less value for unmodified conventional cold galvanizing coating (CG-A at 612 °C. The increase in thermal stability with increasing the concentration of nanocomposite particles could be mainly attributed to the interface surface interaction between the nanocomposite particles and alkyd resin matrix in which enhancing the inorganic-organic network stiffness by causing a reduction in the total free spaces and enhancement in the cross-linking density of the cured film

Composite electrolyte with proton conductivity for low-temperature solid oxide fuel cell

Energy Technology Data Exchange (ETDEWEB)

Raza, Rizwan, E-mail: razahussaini786@gmail.com [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Energy Technology, Royal Institute of Technology, KTH, Stockholm 10044 (Sweden); Ahmed, Akhlaq; Akram, Nadeem; Saleem, Muhammad; Niaz Akhtar, Majid; Ajmal Khan, M.; Abbas, Ghazanfar; Alvi, Farah; Yasir Rafique, M. [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Sherazi, Tauqir A. [Department of Chemistry, COMSATS Institute of Information Technology, Abbotabad 22060 (Pakistan); Shakir, Imran [Sustainable Energy Technologies (SET) center, College of Engineering, King Saud University, PO-BOX 800, Riyadh 11421 (Saudi Arabia); Mohsin, Munazza [Department of Physics, Lahore College for Women University, Lahore, 54000 (Pakistan); Javed, Muhammad Sufyan [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Zhu, Bin, E-mail: binzhu@kth.se, E-mail: zhubin@hubu.edu.cn [Department of Energy Technology, Royal Institute of Technology, KTH, Stockholm 10044 (Sweden); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Faculty of Physics and Electronic Science/Faculty of Computer and Information, Hubei University, Wuhan, Hubei 430062 (China)

2015-11-02

In the present work, cost-effective nanocomposite electrolyte (Ba-SDC) oxide is developed for efficient low-temperature solid oxide fuel cells (LTSOFCs). Analysis has shown that dual phase conduction of O{sup −2} (oxygen ions) and H{sup +} (protons) plays a significant role in the development of advanced LTSOFCs. Comparatively high proton ion conductivity (0.19 s/cm) for LTSOFCs was achieved at low temperature (460 °C). In this article, the ionic conduction behaviour of LTSOFCs is explained by carrying out electrochemical impedance spectroscopy measurements. Further, the phase and structure analysis are investigated by X-ray diffraction and scanning electron microscopy techniques. Finally, we achieved an ionic transport number of the composite electrolyte for LTSOFCs as high as 0.95 and energy and power density of 90% and 550 mW/cm{sup 2}, respectively, after sintering the composite electrolyte at 800 °C for 4 h, which is promising. Our current effort toward the development of an efficient, green, low-temperature solid oxide fuel cell with the incorporation of high proton conductivity composite electrolyte may open frontiers in the fields of energy and fuel cell technology.

Composite electrolyte with proton conductivity for low-temperature solid oxide fuel cell

Science.gov (United States)

Raza, Rizwan; Ahmed, Akhlaq; Akram, Nadeem; Saleem, Muhammad; Niaz Akhtar, Majid; Sherazi, Tauqir A.; Ajmal Khan, M.; Abbas, Ghazanfar; Shakir, Imran; Mohsin, Munazza; Alvi, Farah; Javed, Muhammad Sufyan; Yasir Rafique, M.; Zhu, Bin

2015-11-01

In the present work, cost-effective nanocomposite electrolyte (Ba-SDC) oxide is developed for efficient low-temperature solid oxide fuel cells (LTSOFCs). Analysis has shown that dual phase conduction of O-2 (oxygen ions) and H+ (protons) plays a significant role in the development of advanced LTSOFCs. Comparatively high proton ion conductivity (0.19 s/cm) for LTSOFCs was achieved at low temperature (460 °C). In this article, the ionic conduction behaviour of LTSOFCs is explained by carrying out electrochemical impedance spectroscopy measurements. Further, the phase and structure analysis are investigated by X-ray diffraction and scanning electron microscopy techniques. Finally, we achieved an ionic transport number of the composite electrolyte for LTSOFCs as high as 0.95 and energy and power density of 90% and 550 mW/cm2, respectively, after sintering the composite electrolyte at 800 °C for 4 h, which is promising. Our current effort toward the development of an efficient, green, low-temperature solid oxide fuel cell with the incorporation of high proton conductivity composite electrolyte may open frontiers in the fields of energy and fuel cell technology.

Cold exposure increases slow-type myosin heavy chain 1 (MyHC1) composition of soleus muscle in rats.

Science.gov (United States)

Mizunoya, Wataru; Iwamoto, Yohei; Sato, Yusuke; Tatsumi, Ryuichi; Ikeuchi, Yoshihide

2014-03-01

The aim of this study was to examine the effects of cold exposure on rat skeletal muscle fiber type, according to myosin heavy chain (MyHC) isoform and metabolism-related factors. Male Wistar rats (7 weeks old) were housed individually at 4 ± 2°C as a cold-exposed group or at room temperature (22 ± 2°C) as a control group for 4 weeks. We found that cold exposure significantly increased the slow-type MyHC1 content in the soleus muscle (a typical slow-type fiber), while the intermediate-type MyHC2A content was significantly decreased. In contrast to soleus, MyHC composition of extensor digitorum longus (EDL, a typical fast-type fiber) and gastrocnemius (a mix of slow-type and fast-type fibers) muscle did not change from cold exposure. Cold exposure increased mRNA expression of mitochondrial uncoupling protein 3 (UCP3) in both the soleus and EDL. Cold exposure also increased mRNA expression of myoglobin, peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α) and forkhead box O1 (FOXO1) in the soleus. Upregulation of UCP3 and PGC1α proteins were observed with Western blotting in the gastrocnemius. Thus, cold exposure increased metabolism-related factors in all muscle types that were tested, but MyHC isoforms changed only in the soleus. © 2013 Japanese Society of Animal Science.

The Composition, Antioxidant and Antibacterial Activities of Cold-Pressed and Distilled Essential Oils of Citrus paradisi and Citrus grandis (L. Osbeck

Directory of Open Access Journals (Sweden)

Ming-Chiu Ou

2015-01-01

Full Text Available The chemical composition and functional activities of cold-pressed and water distilled peel essential oils of Citrus paradisi (C. paradisi and Citrus grandis (L. Osbeck (C. grandis were investigated in present study. Yields of cold-pressed oils were much higher than those of distilled oils. Limonene was the primary ingredient of essential oils of C. paradisi (cold 92.83%; distilled 96.06% and C. grandis (cold 32.63%; distilled 55.74%. In addition, C. grandis oils obtained were rich in oxygenated or nitrogenated compounds which may be involved in reducing cardiovascular diseases or enhancing sleep effectiveness. The order of free radical scavenging activities of 4 citrus oils was distilled C. paradisi oil > cold-pressed C. paradisi oil > distilled C. grandis oil > cold-pressed C. grandis oil. Cold-pressed C. grandis oil exhibited the lowest activity in all antioxidative assays. The order of antimicrobial activities of 4 citrus oils was distilled C. grandis oil, cold-pressed C. paradisi oil > distilled C. paradisi oil > cold-pressed C. paradisi oil. Surprisingly, distilled C. grandis oil exhibited better antimicrobial activities than distilled C. paradisi oil, especially against Escherichia coli and Salmonella enterica subsp. The results also indicated that the antimicrobial activities of essential oils may not relate to their antioxidative activities.

Porous Composite for Bipolar Plate in Low Emission Hydrogen Fuel Cells

Directory of Open Access Journals (Sweden)

Renata Katarzyna Włodarczyk

2018-01-01

Full Text Available The paper presents the results of graphite-stainless steel composites for the bipolar plates in low-temperature fuel cells. The sinters were performed by powder metallurgy technology. The influenceof technological parameters, especially molding pressure were examined. Following the requirements formulated by the DOE concerning the parameters of the materials, it indicated by the value of the parameters. The density, flowabilit, particle size of graphite and stainless steel powders have been evaluated. Composites have been tested by microstructure and phase analysis, properties of strength, functional properties: wettability, porosity, roughness. The special attention was paid to the analysis of corrosion resistance obtained sinters and influenceof technological parameters on the corrosion. Corrosion tests were carried out under conditions simulating the environment of the fuel cell under anode and cathode conditions. The effectof pH solution during working of the cell on corrosion resistance of composites have been evaluated. Contact resistance depends on roughness of sinters. Low ICR determined high contact area GDL-BP and high electrical conductivity on the contact surface. The ICR in anode conditions after corrosion tests are not change significantly; composite materials can be used for materials for B in terms of H 2 .

Optimisation of composite metallic fuel for minor actinide transmutation in an accelerator-driven system

Science.gov (United States)

Uyttenhove, W.; Sobolev, V.; Maschek, W.

2011-09-01

A potential option for neutralization of minor actinides (MA) accumulated in spent nuclear fuel of light water reactors (LWRs) is their transmutation in dedicated accelerator-driven systems (ADS). A promising fuel candidate dedicated to MA transmutation is a CERMET composite with Mo metal matrix and (Pu, Np, Am, Cm)O 2-x fuel particles. Results of optimisation studies of the CERMET fuel targeting to increasing the MA transmutation efficiency of the EFIT (European Facility for Industrial Transmutation) core are presented. In the adopted strategy of MA burning the plutonium (Pu) balance of the core is minimized, allowing a reduction in the reactivity swing and the peak power form-factor deviation and an extension of the cycle duration. The MA/Pu ratio is used as a variable for the fuel optimisation studies. The efficiency of MA transmutation is close to the foreseen theoretical value of 42 kg TW -1 h -1 when level of Pu in the actinide mixture is about 40 wt.%. The obtained results are compared with the reference case of the EFIT core loaded with the composite CERCER fuel, where fuel particles are incorporated in a ceramic magnesia matrix. The results of this study offer additional information for the EFIT fuel selection.

Optimisation of composite metallic fuel for minor actinide transmutation in an accelerator-driven system

International Nuclear Information System (INIS)

Uyttenhove, W.; Sobolev, V.; Maschek, W.

2011-01-01

A potential option for neutralization of minor actinides (MA) accumulated in spent nuclear fuel of light water reactors (LWRs) is their transmutation in dedicated accelerator-driven systems (ADS). A promising fuel candidate dedicated to MA transmutation is a CERMET composite with Mo metal matrix and (Pu, Np, Am, Cm)O 2-x fuel particles. Results of optimisation studies of the CERMET fuel targeting to increasing the MA transmutation efficiency of the EFIT (European Facility for Industrial Transmutation) core are presented. In the adopted strategy of MA burning the plutonium (Pu) balance of the core is minimized, allowing a reduction in the reactivity swing and the peak power form-factor deviation and an extension of the cycle duration. The MA/Pu ratio is used as a variable for the fuel optimisation studies. The efficiency of MA transmutation is close to the foreseen theoretical value of 42 kg TW -1 h -1 when level of Pu in the actinide mixture is about 40 wt.%. The obtained results are compared with the reference case of the EFIT core loaded with the composite CERCER fuel, where fuel particles are incorporated in a ceramic magnesia matrix. The results of this study offer additional information for the EFIT fuel selection.

Synthesis of Poly(3,4-Ethylenedioxy thiophene)-Poly(Styrene-4-Sulfonate) Composites for Support Fuel Cell Catalyst Layer

International Nuclear Information System (INIS)

Eko Sulistiyono; Murni Handayani

2009-01-01

Synthesis of poly(3,4-ethylenedioxy thiophene)-poly(styrene-4-sulfonate) composites for support fuel cell catalyst layer are synthesis composites which become fuel cell catalyst support so that catalyst has optimal performance. Main function of composites is support platinum particle for application in fuel cell. This article explains the result of composites production process from ( 3,4 Ethylenedioxy thiophene) and Sodium poly( styrene - 4-sulfonate) using two methods Jingning Shan method (method 1) and Zhigang Qi and Peter G.Pickup method (method 2). Analysis of the synthesis results used Scanning Electron Microscopic –Electron Dispersive X – Ray Spectrophotometer (SEM-EDS ). The analysis result show that both methods produce polymer agglomerate into a sponge-like morphology. Composite from method 1 has morphology, pores and proton transport better than composite produced by method 2. (author)

Comparison of Gasoline Direct-Injection (GDI) and Port Fuel Injection (PFI) Vehicle Emissions: Emission Certification Standards, Cold-Start, Secondary Organic Aerosol Formation Potential, and Potential Climate Impacts.

Science.gov (United States)

Saliba, Georges; Saleh, Rawad; Zhao, Yunliang; Presto, Albert A; Lambe, Andrew T; Frodin, Bruce; Sardar, Satya; Maldonado, Hector; Maddox, Christine; May, Andrew A; Drozd, Greg T; Goldstein, Allen H; Russell, Lynn M; Hagen, Fabian; Robinson, Allen L

2017-06-06

Recent increases in the Corporate Average Fuel Economy standards have led to widespread adoption of vehicles equipped with gasoline direct-injection (GDI) engines. Changes in engine technologies can alter emissions. To quantify these effects, we measured gas- and particle-phase emissions from 82 light-duty gasoline vehicles recruited from the California in-use fleet tested on a chassis dynamometer using the cold-start unified cycle. The fleet included 15 GDI vehicles, including 8 GDIs certified to the most-stringent emissions standard, superultra-low-emission vehicles (SULEV). We quantified the effects of engine technology, emission certification standards, and cold-start on emissions. For vehicles certified to the same emissions standard, there is no statistical difference of regulated gas-phase pollutant emissions between PFIs and GDIs. However, GDIs had, on average, a factor of 2 higher particulate matter (PM) mass emissions than PFIs due to higher elemental carbon (EC) emissions. SULEV certified GDIs have a factor of 2 lower PM mass emissions than GDIs certified as ultralow-emission vehicles (3.0 ± 1.1 versus 6.3 ± 1.1 mg/mi), suggesting improvements in engine design and calibration. Comprehensive organic speciation revealed no statistically significant differences in the composition of the volatile organic compounds emissions between PFI and GDIs, including benzene, toluene, ethylbenzene, and xylenes (BTEX). Therefore, the secondary organic aerosol and ozone formation potential of the exhaust does not depend on engine technology. Cold-start contributes a larger fraction of the total unified cycle emissions for vehicles meeting more-stringent emission standards. Organic gas emissions were the most sensitive to cold-start compared to the other pollutants tested here. There were no statistically significant differences in the effects of cold-start on GDIs and PFIs. For our test fleet, the measured 14.5% decrease in CO 2 emissions from GDIs was much greater than

Diesel CPO for SOFC. Development of a cold-flame assisted CPO reactor coupled to a SOFC

Energy Technology Data Exchange (ETDEWEB)

Van Dijk, H.A.J.; Ouweltjes, J.P.; Nyqvist, R.G. [ECN Hydrogen and Clean Fossil Fuels, Petten (Netherlands)

2009-07-15

Within the research program 'Reforming of liquid fuels for fuel-cells', ECN started a project on the development of a diesel CPO (catalytic partial oxidation) reformer for SOFC (solid oxide fuel cell) in 2005. The application in mind is a small scale (5kWe) diesel fed auxiliary power unit (APU). The goal of the project is to develop the technology required to transform a liquid logistic fuel into a reformat suitable for the operation of a SOFC. The emphasis of this work is on the development of a cold-flame assisted evaporator/mixer coupled to a catalytic CPO reformer. The application of cold-flame evaporation and mixing allows the reformat to be directly fed to the SOFC without further heating or cooling. Moreover, once cold-flames are ignited and stabilized, pre-heating of the air and fuel becomes obsolete. These aspects justify the development described in this report. In the cold-flame evaporator/mixer, the cold-flames are stabilized by means of a recirculation tube. The momentum of the fuel spray of the nozzle induces the required recirculation. The cold flame evaporator/mixer was coupled to a catalytic reformer reactor, transforming the hydrocarbon+air feed into a CO+H2 rich reformate. The reformer was coupled to a SOFC to be able to verify the quality of the reformat obtained with this reformer. The SOFC therefore served as an analysis tool. Characteristically, the reformat was held at 800C all the way towards the SOFC. For this, high temperature flange connections and steel-ceramic expansion connections were successfully applied. It is demonstrated that cold-flame evaporation of liquid fuels is a feasible means of feed preparation for a catalytic reforming reactor. The quality of the resulting reformat is adequate to be fed to the SOFC. The reformat quality, however, decreased with time-on-stream due to fouling of the reformer by carbon-depositions. These carbon-depositions were essentially located on the fuel injector, which is the coldest part

OTEC Advanced Composite Cold Water Pipe: Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Dr. Alan Miller; Matthew Ascari

2011-09-12

Ocean Thermal Energy Conversion can exploit natural temperature gradients in the oceans to generate usable forms of energy (for example, cost-competitive baseload electricity in tropical regions such as Hawaii) free from fossil fuel consumption and global warming emissions.The No.1 acknowledged challenge of constructing an OTEC plant is the Cold Water Pipe (CWP), which draws cold water from 1000m depths up to the surface, to serve as the coolant for the OTEC Rankine cycle. For a commercial-scale plant, the CWP is on the order of 10m in diameter.This report describes work done by LMSSC developing the CWP for LM MS2 New Ventures emerging OTEC business. The work started in early 2008 deciding on the minimum-cost CWP architecture, materials, and fabrication process. In order to eliminate what in previous OTEC work had been a very large assembly/deployment risk, we took the innovative approach of building an integral CWP directly from theOTEC platform and down into the water. During the latter half of 2008, we proceeded to a successful small-scale Proof-of-Principles validation of the new fabrication process, at the Engineering Development Lab in Sunnyvale. During 2009-10, under the Cooperative Agreement with the US Dept. of Energy, we have now successfully validated key elements of the process and apparatus at a 4m diameter scale suitable for a future OTEC Pilot Plant. The validations include: (1) Assembly of sandwich core rings from pre-pultruded hollow 'planks,' holding final dimensions accurately; (2) Machine-based dispensing of overlapping strips of thick fiberglass fabric to form the lengthwise-continuous face sheets, holding accurate overlap dimensions; (3) Initial testing of the fabric architecture, showing that the overlap splices develop adequate mechanical strength (work done under a parallel US Naval Facilities Command program); and (4) Successful resin infusion/cure of 4m diameter workpieces, obtaining full wet-out and a non-discernable knitline

Effect of cold rolling on fatigue crack propagation of TiNi/A16061 shape memory composite

International Nuclear Information System (INIS)

Lee, Jin Kyung; Lee, Sang Pill; Park, Young Chul; Lee, Kyu Chang; Cho, Youn Ho; Lee, Joon Hyun

2005-01-01

TiNi alloy fiber was used to recover the original shape of materials using its shape memory effect. The shape memory alloy plays an important role within the metal matrix composite. The shape memory alloy can control the crack propagation in metal matrix composite, and improve the tensile strength of the composite. In this study, TiNi/A16061 Shape Memory Alloy(SMA) composite was fabricated by hot press method, and pressed by a roller for its strength improvement. The four kinds of specimens were fabricated with 0%, 3.2%, 5.2% and 7% volume fraction of TiNi alloy fiber, respectively. A fatigue test has performed to evaluate the crack initiation and propagation for the TiNi/A16061 SMA composite fabricated by this method. In order to study the shape memory effect of the TiNi alloy fiber, the test has also done under both conditions of the room temperature and high temperature. The relationship between the crack growth rate and the stress intensity factor was clarified for the composite, and the cold rolling effect was also studied

Method of fabricating zirconium metal for use in composite type fuel cans

International Nuclear Information System (INIS)

Imahashi, Hiromichi; Inagaki, Masatoshi; Akabori, Kimihiko; Tada, Naofumi; Yasuda, Tetsuro.

1985-01-01

Purpose: To mass produce zirconium metal for fuel cans with less radiation hardening. Method: Zirconium sponges as raw material are inserted in a hearth mold and a procedure of melting the zirconium sponges portionwise by using a melting furnace having electron beams as a heat source while moving the hearth is repeated at least for once. Then, the rod-like ingot after melting is melted again in a vacuum or inert gas atmosphere into an ingot of a low oxygen density capable of fabrication. A composite fuel can billet is formed by using the thus obtained zirconium ingot and a zircalloy, and a predetermined composite type fuel can is manufactured by way of hot extrusion and pipe drawing fabrication. The raw material usable herein is zirconium sponge with an oxygen density of 400 ppm or higher and the content of impurity other than oxygen is between 1000 - 5000 ppm in total, or the molten material thereof. (Kamimura, M.)

Method of producing exfoliated graphite composite compositions for fuel cell flow field plates

Energy Technology Data Exchange (ETDEWEB)

Zhamu, Aruna; Shi, Jinjun; Guo, Jiusheng; Jang, Bor Z

2014-04-08

A method of producing an electrically conductive composite composition, which is particularly useful for fuel cell bipolar plate applications. The method comprises: (a) providing a supply of expandable graphite powder; (b) providing a supply of a non-expandable powder component comprising a binder or matrix material; (c) blending the expandable graphite with the non-expandable powder component to form a powder mixture wherein the non-expandable powder component is in the amount of between 3% and 60% by weight based on the total weight of the powder mixture; (d) exposing the powder mixture to a temperature sufficient for exfoliating the expandable graphite to obtain a compressible mixture comprising expanded graphite worms and the non-expandable component; (e) compressing the compressible mixture at a pressure within the range of from about 5 psi to about 50,000 psi in predetermined directions into predetermined forms of cohered graphite composite compact; and (f) treating the so-formed cohered graphite composite to activate the binder or matrix material thereby promoting adhesion within the compact to produce the desired composite composition. Preferably, the non-expandable powder component further comprises an isotropy-promoting agent such as non-expandable graphite particles. Further preferably, step (e) comprises compressing the mixture in at least two directions. The method leads to composite plates with exceptionally high thickness-direction electrical conductivity.

Application of a cold spray technique to the fabrication of a copper canister for the geological disposal of CANDU spent fuels

Energy Technology Data Exchange (ETDEWEB)

Choi, Heui-Joo, E-mail: hjchoi@kaeri.re.k [Korea Atomic Energy Research Institute, Radioactive Waste Management Technology Development, 150 Dukjin-dong, Yuseong, Daejon, 305-353 (Korea, Republic of); Lee, Minsoo; Lee, Jong Youl [Korea Atomic Energy Research Institute, Radioactive Waste Management Technology Development, 150 Dukjin-dong, Yuseong, Daejon, 305-353 (Korea, Republic of)

2010-10-15

A new method was proposed for the manufacture of a copper-cast iron canister for the spent fuel disposal based on the cold spray coating technique. The thickness of a copper shell could be fabricated to be as thin as 10 mm with the new method. Around 6 tons of copper could be saved with a 10 mm thick canister compared with a 50 mm thick canister. The electrochemical properties of the cold sprayed copper layer and forged copper were measured through a polarization test. The two copper layers showed very similar electrochemical properties. The lifetime of a 10 mm copper canister was estimated with a mathematical model based on the mass transport of sulfide ions through the buffer. The results showed that the canister lifetime was more than 140,000 years under the Korean granite groundwater condition. The thermal analysis with a current pre-conceptual design of a CANDU spent fuel canister showed that the maximum temperature between the canister and the saturated buffer was below the thermal criteria, 100 {sup o}C. Finally, the mechanical stability of the copper canister was confirmed with a computer program, ABAQUS, under the rock movement scenario.

Mercury concentrations, speciation, and isotopic composition in sediment from a cold seep in the northern Gulf of Mexico

International Nuclear Information System (INIS)

Brown, Garry; Sleeper, Kenneth; Johnson, Marcus W.; Blum, Joel D.; Cizdziel, James V.

2013-01-01

Highlights: • T-Hg, MMHg, and Hg isotopes were determined in Gulf of Mexico deep marine sediments. • Levels of mass independent fractionation of Hg isotopes varied from coastal sediments. • Levels of the MMHg were only slightly elevated at the cold seep site. • Cold seeps do not appear to be significant sources of MMHg to Gulf of Mexico waters. -- Abstract: Total-Hg, monomethylmercury (MMHg), and mercury isotopic composition was determined in sediment from a cold seep and background sites in the northern Gulf of Mexico (nGoM). Total-Hg averaged 50 ng/g (n = 28), ranged from 31 to 67 ng/g, and decreased with depth (0–15 cm). MMHg averaged 0.91 ng/g (n = 18), and ranged from 0.2 to 1.9 ng/g. There was no significant difference for total-Hg or MMHg between cold seep and background sites. δ 202 Hg ranged from −0.5 to −0.8‰ and becomes more negative with depth (r = 0.989). Mass independent fractionation (Δ 199 Hg) was small but consistently positive (0.04–0.12‰); there was no difference between cold seeps (Δ 199 Hg = +0.09 ± 0.03; n = 7, 1SD) and background sites (Δ 199 Hg = +0.07 ± 0.02; n = 5, 1SD). This suggests that releases of hydrocarbons at the cold seep do not significantly alter Hg levels, and that cold seeps are likely not major sources of MMHg to nGoM waters

New UO2 fuel studies

International Nuclear Information System (INIS)

Dehaudt, P.; Lemaignan, C.; Caillot, L.; Mocellin, A.; Eminet, G.

1998-01-01

With improved UO 2 fuels, compared with the current PWR, one would enable to: retain the fission products, rise higher burn-ups and deliver the designed power in reactor for longer times, limit the pellet cladding interaction effects by easier deformation at high temperatures. Specific studies are made in each field to understand the basic mechanisms responsible for these improvements. Four programs on new UO 2 fuels are underway in the laboratory: advanced microstructure fuels (doped fuels), fuels containing Er 2 O 3 a burnable absorber, fuels with improved caesium retention, composite fuels. The advanced microstructure UO 2 fuels have special features such as: high grain sizes to lengthen the fission gas diffusion paths, intragranular precipitates as fission gas atoms pinning sites, intergranular silica based viscoplastic phases to improve the creep properties. The grain size growth can be obtained with a long time annealing or with corundum type oxide additives partly soluble in the UO 2 lattice. The amount of doping element compared with its solubility limit and the sintering conditions allows to obtain oxide or metallic precipitates. The fuels containing Er 2 O 3 as a burnable absorber are under irradiation in the TANOX device at the present time. Specific sintering conditions are required to improve the erbium solubility in UO 2 and to reach standard or large grain sizes. The improved caesium retention fuels are doped with SiO 2 +A1 2 O 3 or SiO 2 +ZrO 2 additives which may form stable compounds with the Cs element in accidental conditions. The composite fuels are made of UO 2 particles of about 100 μm in size dispersed in a molybdenum metallic (CERMET) or MgA1 2 O 4 ceramic (CERCER) matrix. The CERMET has a considerably higher thermal conductivity and remains ''cold'' during irradiation. The concept of double barrier (matrix+fuel) against fission products is verified for the CERMET fuel. A thermal analysis of all the irradiated rods shows that the thermal

Cold shock on the wood fuel industry

International Nuclear Information System (INIS)

Queyrel, A.

2008-01-01

The development of the wood fuel industry represents one of the pillars of the European energy plan, and in particular of the French energy policy, as it fulfills both objectives of development of renewable energy sources and CO 2 balance. The wood fuel industry supplies 6% of the French energy consumption and has permitted to save more than 9 million tons of petroleum equivalent. However, the conclusions of the European project CARBOSOL stress on the strong health impacts of wood-fueled combustion systems, in particular in the case of domestic individual systems and appliances. The combustion of biomass (fireplaces and agriculture) is responsible for 50 to 70% of the winter carbon pollution in Europe. The situation of collective or industrial wood-fueled facilities is different since pollution control solutions can be more easily implemented. (J.S.)

Influence of cold rolling and fatigue on the residual stress state of a metal matrix composite

International Nuclear Information System (INIS)

Hanus, E.; Ericsson, T.; Lu, J.; Decomps, F.

1993-01-01

The large difference in the coefficient of thermal expansion between the matrix alloy and the particle in a metal matrix composite gives rise to residual stresses in the material. In the present work the effect of cold rolling and four-point bending fatigue on the residual stress state of a silicon carbide particle reinforced aluminium alloy (AA 2014) has been investigated. The three dimensional stress state measured in both phases: matrix and reinforcement, has been determined by using an X-ray diffraction technique. It was found that cold rolling induces surface compressive macrostresses of about -250 MPa, with a penetration depth around 2 mm. The absolute values of the pseudomacrostresses in both phases are significantly reduced due to the single track rolling. Stress relaxation occurs during four-point bending fatigue. (orig.)

Advanced diesel electronic fuel injection and turbocharging

Science.gov (United States)

Beck, N. J.; Barkhimer, R. L.; Steinmeyer, D. C.; Kelly, J. E.

1993-12-01

The program investigated advanced diesel air charging and fuel injection systems to improve specific power, fuel economy, noise, exhaust emissions, and cold startability. The techniques explored included variable fuel injection rate shaping, variable injection timing, full-authority electronic engine control, turbo-compound cooling, regenerative air circulation as a cold start aid, and variable geometry turbocharging. A Servojet electronic fuel injection system was designed and manufactured for the Cummins VTA-903 engine. A special Servojet twin turbocharger exhaust system was also installed. A series of high speed combustion flame photos was taken using the single cylinder optical engine at Michigan Technological University. Various fuel injection rate shapes and nozzle configurations were evaluated. Single-cylinder bench tests were performed to evaluate regenerative inlet air heating techniques as an aid to cold starting. An exhaust-driven axial cooling air fan was manufactured and tested on the VTA-903 engine.

Processing of carbon composite paper as electrode for fuel cell

Energy Technology Data Exchange (ETDEWEB)

Mathur, R.B.; Maheshwari, Priyanka H.; Dhami, T.L. [Carbon Technology Unit, National Physical Laboratory, New Delhi 110012 (India); Sharma, R.K.; Sharma, C.P. [Soft Polymeric Group, Division of Engineering Materials, National Physical Laboratory, New Delhi 110012 (India)

2006-10-27

The porous carbon electrode in a fuel cell not only acts as an electrolyte and a catalyst support, but also allows the diffusion of hydrogen fuel through its fine porosity and serves as a current-carrying conductor. A suitable carbon paper electrode is developed and possesses the characteristics of high porosity, permeability and strength along with low electrical resistivity so that it can be effectively used in proton-exchange membrane and phosphoric acid fuel cells. The electrode is prepared through a combination of two important techniques, viz., paper-making technology by first forming a porous chopped carbon fibre preform, and composite technology using a thermosetting resin matrix. The study reveals an interdependence of one parameter on another and how judicious choice of the processing conditions are necessary to achieve the desired characteristics. The current-voltage performance of the electrode in a unit fuel cell matches that of a commercially-available material. (author)

Effects of actinide compositional variability in the U.S. spent fuel inventory on partitioning-transmutation systems

International Nuclear Information System (INIS)

Ludwig, S.B.; Michaels, G.E.; Hanson, B.D.

1993-01-01

The partitioning and transmutation concept (P-T) has as a mission the reduction by many orders of magnitude of certain undesirable nuclides in the waste streams. Given that only a very small fiction of spent fuel can be rejected by a P-T enterprise, a P-T system must therefore be capable of accommodating a wide range of spent fuel characteristics. Variability of nuclide composition (i.e. the feed material for transmutation devices) may be important because virtually all transmutation systems propose to configure TRU nuclides recovered from discharged LWR fuel in critical or near-critical cores. To date, all transmutation system core analyses assume nonvariable nuclide concentrations for startup and recycle cores. Using the Department of Energy (DOES) Characteristic Data Base (CDB) and the ORIGEN2 computer code, the current and projected spent fuel discharges until the year 2016 have been categorized according to combinations of fuel burnup, initial enrichment, fuel age (cooling time) and reactor type (boiling-water or pressurized-water reactor). In addition to quantifying the variability of nuclide composition in current and projected LWR fuel discharge, the variability of the infinite multiplication factor (K ∞ ) is calculated for both fast (ALMR) and thermal (accelerator-based) transmuter systems. It is shown that actinide compositional variations are potentially significant and warrant further investigation. (authors)

Investigation of the internal behavior in segmented PEMFCs of different flow fields during cold start process

International Nuclear Information System (INIS)

Lin, R.; Ren, Y.S.; Lin, X.W.; Jiang, Z.H.; Yang, Z.; Chang, Y.T.

2017-01-01

In this study, we have researched the internal behavior in segmented proton exchange membrane fuel cells (PEMFCs) with three different flow fields during cold start process. The change of internal current density and temperature in fuel cells with different flow fields could be obviously shown by the printed circuit board (PCB) technology, and the study shows that the flow field is significant for enhancing the cold start ability and durability. Single serpentine flow field has the best cold start performance, while triple channel serpentine flow field has the best uniformity. It is found that without a robust temperature rising tendency, the cell temperature reaching 0 °C does not definitely mean a successful cold start because the cell temperature might drop down 0 °C again. Polarization curves show that there is almost no performance degradation after successful cold start, but the cell degrades quickly after the failed cold start at −7 °C and −10 °C. Based on these characteristics, we optimized the rapid cold start strategy by using electric heating and make it possible to start up the PEMFC at temperatures down to −20 °C within about 11 min. - Highlights: • Segmented fuel cell were used to record the internal current density and temperature distributions during the cold start. • The effects of flow fields on the PEMFC cold start capacity were evaluated. • The effect of cold start on the performance of fuel cell was evaluated. • An optimized strategy was adopted to improve the cold start capacity.

Trophic structure of cold-water coral communities revealed from the analysis of tissue isotopes and fatty acid composition

NARCIS (Netherlands)

Van Oevelen, D.; Duineveld, G.; Lavaleye, M.S.S.; Kutti, T.; Soetaert, K.

2018-01-01

The trophic structure of cold-water coral reef communities at two contrasting locations, the 800-m deep Belgica Mounds (Irish margin) and the 300-m deep Træna reefs (Norwegian Shelf), was investigated using stable isotope (δ13C and δ15N) and fatty-acid composition analysis. A broad range of

Fabrication of carbon-polymer composite bipolar plates for polymer electrolyte membrane fuel cells by compression moulding

International Nuclear Information System (INIS)

Raza, M.A.; Ahmed, R.; Saleem, A.; Din, R.U.

2009-01-01

Fuel cells are considered as one of the most important technologies to address the future energy and environmental pollution problems. These are the most promising power sources for road transportation and portable devices. A fuel cell is an electrochemical device that converts chemical energy into electrical energy. A fuel cell stack consists of bipolar plates and membrane electrode assemblies (MEA). The bipolar plate is by weight, volume and cost one of the most significant components of a fuel cell stack. Major functions of bipolar plates are to separate oxidant and fuel gas, provide flow channels, conduct electricity and provide heat transfer. Bipolar plates can be made from various materials including graphite, metals, carbon / carbon and carbon/ polymer composites. Materials for carbon-polymer composites are relatively inexpensive, less corrosive, strong and channels can be formed by means of a moulding process. Carbon-polymer composites are of two type i.e; thermosetting and thermoplastic. For thermosetting composite a bulk molding compound (BMC) was prepared by adding graphite, vinyl ester resin, methyl ethyl ketone peroxide and cobalt naphthalate. The BMC was thoroughly mixed, poured into a die mould of a bipolar plate with channels and hot pressed at a specific temperature and pressure. A bipolar plate was formed according to the die mould. Design of the mould is also discussed. Conducting polymers were also added to BMC to increase the conductivity of bipolar plates. Particle size of the graphite has also a significant effect on the conductivity of the bipolar plates. Thermoplastic composites were also prepared using polypropylene and graphite.

Effect of strengthening mechanisms on cold workability and instantaneous strain hardening behavior during grain refinement of AA 6061-10 wt.% TiO2 composite prepared by mechanical alloying

International Nuclear Information System (INIS)

Sivasankaran, S.; Sivaprasad, K.; Narayanasamy, R.; Iyer, Vijay Kumar

2010-01-01

Research highlights: → Various strengthening mechanisms such as solid solution, grain size, precipitate, dislocation and dispersion strengthening promoted yield strength of the composites → The 5 h sintered composite yielded a large plastic strain (23%) at ambient temperature. → The domination of interparticle friction effects, grain size and dislocation strengthening diminished the deformation capacity of the composites greater than 5 h of milling. → Ultra-fine grained composite (40 h) yielded a high strength (>1000 MPa). → The proposed instantaneous new Poisson's ratio and the instantaneous strain hardening index used to study the extent of plastic zone and strain levels of the composite. - Abstract: The mechanical alloying (MA) of AA 6061 alloy reinforced with 10 wt.% fine anatase-titania composites powder milled with different timings (1, 5, 10, 20, 30, and 40 h) was cold consolidated and sintered. The main purpose of this study is to investigate the effect of microstructure and the various strengthening mechanisms such as solid solution, grain size, precipitate, dislocation and dispersion strengthening during grain refinement of AA 6061-10 wt.% TiO 2 composite via MA on cold working and strain hardening behavior. The sintered composite preforms were characterized by X-ray diffraction, scanning electron microscope, and transmission electron microscope. The strengthening mechanisms were estimated by using simplified models available in the literatures. The evaluation of cold deformation behavior under triaxial stress condition through room temperature cold-upsetting tests (incremental loads) was studied by correlating the strengthening mechanisms. Among the developed strengthening mechanisms the grain size and dislocation strengthening mechanisms diminished the deformation capacity of the composites. The strain hardening behavior was also examined by proposing instantaneous strain hardening index (n i ). The value of maximum instantaneous strain

α-MnO2 Nanowires/Graphene Composites with High Electrocatalytic Activity for Mg-Air Fuel Cell

International Nuclear Information System (INIS)

Jiang, Min; He, Hao; Huang, Chen; Liu, Bo; Yi, Wen-Jun; Chao, Zi-Sheng

2016-01-01

Highlights: • α-MnO 2 NWs/graphene was synthesized and studied in Mg-air fuel cell. • The performance of α-MnO 2 NWs/graphene is close to the Pt/C. • The ORR mechanism involves a one-step, quasi-4-electron pathway. • A large area (5 cm*5 cm) cathode was prepared and tested in a full cell. - Abstract: This paper reports the preparation of α-MnO 2 NWs/graphene composites as the cathode catalyst for magnesium-air fuel cell and its excellent electrochemistry performance. The composites are synthesized by self-assembly of α-MnO 2 nan α-MnO 2 NWs/graphene was synthesized and studied in Mg-air fuel cell. α-MnO 2 NWs/graphene was synthesized and studied in Mg-air fuel cell. owires (NWs) on the surface of graphene via a simple hydrothermal method. The α-MnO 2 NWs/graphene composites showed a higher electrochemical activity than the commercial MnO 2 . The oxygen reduction peak of the α-MnO 2 NWs/graphene composites catalyst is tested in a 0.1 M KOH solution at −0.252 V, which is more positive than the commercial MnO 2 (−0.287 V). The ORR limit current density for 28% α-MnO2 NWs/graphene composite is approximately 2.74 mA/cm 2 , which is similar to that of the 20% Pt/C(2.79 mA/cm 2 ) in the same conditions. Based on the Koutecky–Levich plot, the ORR mechanism of the composite involves a one-step, quasi-4-electron pathway. In addition, magnesium-air fuel cell with α-MnO 2 NWs/graphene as catalyst possesses higher current density (140 mA/cm 2 ) and power density (96 mW/cm 2 ) compared to the commercial MnO 2 . This study proves that the cost-effective α-MnO 2 NWs/graphene with higher power generation ability make it possible for the substitute of the noble metals catalyst in the Mg-air fuel cell.

Modeling of combustion products composition of hydrogen-containing fuels

International Nuclear Information System (INIS)

Assad, M.S.

2010-01-01

Due to the usage of entropy maximum principal the algorithm and the program of chemical equilibrium calculation concerning hydrogen--containing fuels are devised. The program enables to estimate the composition of combustion products generated in the conditions similar to combustion conditions in heat engines. The program also enables to reveal the way hydrogen fraction in the conditional composition of the hydrocarbon-hydrogen-air mixture influences the harmful components content. It is proven that molecular hydrogen in the mixture is conductive to the decrease of CO, CO 2 and CH x concentration. NO outlet increases due to higher combustion temperature and N, O, OH concentrations in burnt gases. (authors)

Fabrication and Characterization of Graded Anodes for Anode-Supported Solid Oxide Fuel Cells by Tape Casting and Lamination

DEFF Research Database (Denmark)

Beltran-Lopez, J.F.; Laguna-Bercero, M.A.; Gurauskis, Jonas

2014-01-01

Graded anodes for anode-supported solid oxide fuel cells (SOFCs) are fabricated by tape casting and subsequent cold lamination of plates using different compositions. Rheological parameters are adjusted to obtain stable suspensions for tape casting. The conditions for the tape casting and laminat......Graded anodes for anode-supported solid oxide fuel cells (SOFCs) are fabricated by tape casting and subsequent cold lamination of plates using different compositions. Rheological parameters are adjusted to obtain stable suspensions for tape casting. The conditions for the tape casting...... and lamination will be described. Flexural strength of the reduced cermets measured using three-point bending configuration is 468±37MPa. The graded anode supports are characterized by scanning electron microscope observations, mercury porosimetry intrusion, and resistivity measurements, showing an adequate...... of tapes at room temperature without using plasticizers. This is made by the combination of two different binders with varying Tg (glass transition temperature) which resulted in plastic deformation at room temperature. Those results indicate that the proposed process is a cost-effective method...

VENUS: cold prototype installation of the head-end of the reprocessing of HTR fuel elements. Activity report, 1 July 1976--31 December 1976

Energy Technology Data Exchange (ETDEWEB)

Boehnert, R.; Walter, C.

1977-02-15

The purpose of the VENUS Project is advance planning for the construction of a cold prototype system to incinerate HTR fuel element graphite. The Venus Project is organized into four phases between advance planning and experimental operation, corresponding to the maturity of the work. It is in the advance planning phase. Status of individual studies is given. (LK)

VENUS: cold prototype installation of the head-end of the reprocessing of HTR fuel elements. Activity report, 1 July 1976--31 December 1976

International Nuclear Information System (INIS)

Boehnert, R.; Walter, C.

The purpose of the VENUS Project is advance planning for the construction of a cold prototype system to incinerate HTR fuel element graphite. The Venus Project is organized into four phases between advance planning and experimental operation, corresponding to the maturity of the work. It is in the advance planning phase. Status of individual studies is given

Composite cathode materials development for intermediate temperature solid oxide fuel cell systems

Science.gov (United States)

Qin, Ya

Solid oxide fuel cell (SOFC) systems are of particular interest as electrochemical power systems that can operate on various hydrocarbon fuels with high fuel-to-electrical energy conversion efficiency. Within the SOFC stack, La0.8Sr 0.2Ga0.8Mg0.115Co0.085O3-delta (LSGMC) has been reported as an optimized composition of lanthanum gallate based electrolytes to achieve higher oxygen ionic conductivity at intermediate temperatures, i.e., 500-700°C. The electrocatalytic properties of interfaces between LSGMC electrolytes and various candidate intermediate-temperature SOFC cathodes have been investigated. Sm0.5Sr0.5CoO 3-delta (SSC), and La0.6Sr0.4Co0.2Fe 0.8O3-delta (LSCF), in both pure and composite forms with LSGMC, were investigated with regards to both oxygen reduction and evolution, A range of composite cathode compositions, having ratios of SSC (in wt.%) with LSGMC (wt.%) spanning the compositions 9:1, 8:2, 7:3, 6:4 and 5:5, were investigated to determine the optimal cathode-electrolyte interface performance at intermediate temperatures. All LSGMC electrolyte and cathode powders were synthesized using the glycine-nitrate process (GNP). Symmetrical electrochemical cells were investigated with three-electrode linear dc polarization and ac impedance spectroscopy to characterize the kinetics of the interfacial reactions in detail. Composite cathodes were found to perform better than the single phase cathodes due to significantly reduced polarization resistances. Among those composite SSC-LSGMC cathodes, the 7:3 composition has demonstrated the highest current density at the equivalent overpotential values, indicating that 7:3 is an optimal mixing ratio of the composite cathode materials to achieve the best performance. For the composite SC-LSGMC cathode/LSGMC interface, the cathodic overpotential under 1 A/cm2 current density was as low as 0.085 V at 700°C, 0.062V at 750°C and 0.051V at 800°C in air. Composite LSCF-LSGMC cathode/LSGMC interfaces were found to have

Spent nuclear fuel project cold vacuum drying facility operations manual

International Nuclear Information System (INIS)

IRWIN, J.J.

1999-01-01

This document provides the Operations Manual for the Cold Vacuum Drying Facility (CVDF). The Manual was developed in conjunction with HNF-SD-SNF-SAR-002, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of Processing Systems (Garvin 1998) and, the HNF-SD-SNF-DRD-002, 1997, Cold Vacuum Drying Facility Design Requirements, Rev. 3a. The Operations Manual contains general descriptions of all the process, safety and facility systems in the CVDF, a general CVD operations sequence, and has been developed for the SNFP Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved

Effect of wrapped Zn plate on the densification of Al-MWCNTs composites produced by cold pressing and liquid phase sintering

Energy Technology Data Exchange (ETDEWEB)

Joo, M.R. [Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Choi, H.J. [School of Advanced Materials Engineering, Kookmin University, Seoul 136-702 (Korea, Republic of); Shin, S.E. [Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Bae, D.H., E-mail: donghyun@yonsei.ac.kr [Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)

2016-09-30

To produce highly dense and cost-effective Al-multi-walled carbon nanotube (Al-MWCNT) composites, the composite powders are wrapped by a Zn plate and then cold-pressed. The green compacts are then sintered at 550 °C, which shows ~99%density after sintering for 24 h. During sintering, Zn atoms fill the voids at the powder boundaries by capillary action and are then dissolved into the Al matrix because of the high solubility of Zn in Al, thus assisting densification of the composite powder. The Al/Zn-based composites containing 4 vol% MWCNTs show compressive yield strength (~380 MPa) and high work hardening capacity.

Encapsulation of TRISO particle fuel in durable soda-lime-silicate glasses

International Nuclear Information System (INIS)

Heath, Paul G.; Corkhill, Claire L.; Stennett, Martin C.; Hand, Russell J.; Meyer, Willem C.H.M.; Hyatt, Neil C.

2013-01-01

Tri-Structural Isotropic (TRISO) coated particle-fuel is a key component in designs for future high temperature nuclear reactors. This study investigated the suitability of three soda lime silicate glass compositions, for the encapsulation of simulant TRISO particle fuel. A cold press and sinter (CPS) methodology was employed to produce TRISO particle–glass composites. Composites produced were determined to have an aqueous durability, fracture toughness and Vickers’ hardness comparable to glasses currently employed for the disposal of high level nuclear wastes. Sintering at 700 °C for 30 min was found to remove all interconnected porosity from the composite bodies and oxidation of the outer pyrolytic carbon layer during sintering was prevented by processing under a 5% H 2 /N 2 atmosphere. However, the outer pyrolytic carbon layer was not effectively wetted by the encapsulating glass matrix. The aqueous durability of the TRISO particle–glass composites was investigated using PCT and MCC-1 tests combined with geochemical modelling. It was found that durability was dependent on silicate and calcium solution saturation. This study provides significant advancements in the preparation of TRISO particle encapsulant waste forms. The potential for the use of non-borosilicate sintered glass composites for TRISO particle encapsulation has been confirmed, although further refinements are required

Encapsulation of TRISO particle fuel in durable soda-lime-silicate glasses

Energy Technology Data Exchange (ETDEWEB)

Heath, Paul G.; Corkhill, Claire L.; Stennett, Martin C.; Hand, Russell J. [Immobilisation Science Laboratory, Department of Materials Science and Engineering, Robert Hadfield Building, University of Sheffield, Sheffield S1 3JD (United Kingdom); Meyer, Willem C.H.M. [Necsa, South African Nuclear Energy Corporation, PO Box 582, Pretoria, Gauteng (South Africa); Hyatt, Neil C., E-mail: n.c.hyatt@sheffield.ac.uk [Immobilisation Science Laboratory, Department of Materials Science and Engineering, Robert Hadfield Building, University of Sheffield, Sheffield S1 3JD (United Kingdom)

2013-05-15

Tri-Structural Isotropic (TRISO) coated particle-fuel is a key component in designs for future high temperature nuclear reactors. This study investigated the suitability of three soda lime silicate glass compositions, for the encapsulation of simulant TRISO particle fuel. A cold press and sinter (CPS) methodology was employed to produce TRISO particle–glass composites. Composites produced were determined to have an aqueous durability, fracture toughness and Vickers’ hardness comparable to glasses currently employed for the disposal of high level nuclear wastes. Sintering at 700 °C for 30 min was found to remove all interconnected porosity from the composite bodies and oxidation of the outer pyrolytic carbon layer during sintering was prevented by processing under a 5% H{sub 2}/N{sub 2} atmosphere. However, the outer pyrolytic carbon layer was not effectively wetted by the encapsulating glass matrix. The aqueous durability of the TRISO particle–glass composites was investigated using PCT and MCC-1 tests combined with geochemical modelling. It was found that durability was dependent on silicate and calcium solution saturation. This study provides significant advancements in the preparation of TRISO particle encapsulant waste forms. The potential for the use of non-borosilicate sintered glass composites for TRISO particle encapsulation has been confirmed, although further refinements are required.

Electrospun Nafion®/Polyphenylsulfone Composite Membranes for Regenerative Hydrogen Bromine Fuel Cells.

Science.gov (United States)

Park, Jun Woo; Wycisk, Ryszard; Pintauro, Peter N; Yarlagadda, Venkata; Van Nguyen, Trung

2016-02-29

The regenerative H₂/Br₂-HBr fuel cell, utilizing an oxidant solution of Br₂ in aqueous HBr, shows a number of benefits for grid-scale electricity storage. The membrane-electrode assembly, a key component of a fuel cell, contains a proton-conducting membrane, typically based on the perfluorosulfonic acid (PFSA) ionomer. Unfortunately, the high cost of PFSA membranes and their relatively high bromine crossover are serious drawbacks. Nanofiber composite membranes can overcome these limitations. In this work, composite membranes were prepared from electrospun dual-fiber mats containing Nafion ® PFSA ionomer for facile proton transport and an uncharged polymer, polyphenylsulfone (PPSU), for mechanical reinforcement, and swelling control. After electrospinning, Nafion/PPSU mats were converted into composite membranes by softening the PPSU fibers, through exposure to chloroform vapor, thus filling the voids between ionomer nanofibers. It was demonstrated that the relative membrane selectivity, referenced to Nafion ® 115, increased with increasing PPSU content, e.g., a selectivity of 11 at 25 vol% of Nafion fibers. H₂-Br₂ fuel cell power output with a 65 μm thick membrane containing 55 vol% Nafion fibers was somewhat better than that of a 150 μm Nafion ® 115 reference, but its cost advantage due to a four-fold decrease in PFSA content and a lower bromine species crossover make it an attractive candidate for use in H₂/Br₂-HBr systems.

Important parameters in ORIGEN2 calculations of spent fuel compositions

International Nuclear Information System (INIS)

Welch, T.D.; Notz, K.J.; Andermann, R.J. Jr.

1990-01-01

The Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM) is responsible for implementing federal policy for the management and permanent disposal of spent nuclear fuel from civilian nuclear power reactors and of high-level radioactive waste. The Characteristics Data Base (CDB) provides an extensive collection of data on the four waste steams that may require long-term isolation: LWR spent fuel, high-level waste, non-LWR spent fuel, and miscellaneous wastes (such as greater-than-class-C). The eight-volume report and the five supplemental menu-driven PC data bases encompass radiological characteristics, chemical compositions, physical descriptions, inventories, and projections. An overview of these data bases, which are available through the Oak Ridge National Laboratory, is provided by Notz. This paper reports that the radiological characteristics in the CDB are calculated using ORIGEN2

Method of determining the composition of fuels for FBR type reactors

International Nuclear Information System (INIS)

Tsutsumi, Kiyoshi.

1981-01-01

Purpose: To improve the core safety of FBR type reactors by determining the composition of fuels composed of oxide mixture of plutonium and uranium, using a relation between specific plutonium seed and plutonium enrichment degree. Method: Relation is determined between the ratio of a specific plutonium seed for constituting plutonium oxide, for example 239 U ratio and a plutonium enrichment degree required for setting the assembly power to a constant level. The ratio of 239 U is plutonium having a given isotopic ratio is also determined. The accuracy of the 239 U ratio can be improved by the correction using the density coefficient. Then, the plutonium enrichment degree is determined using the relation determined as above based on the thus determined 239 U ratio. The composition of the fuel using oxide mixture of plutonium and uranium is determined by utilizing the thus obtained plutonium enrichment degree. (Moriyama, K.)

Some concluding remarks about cold moderator development

International Nuclear Information System (INIS)

Carpenter, J.M.

1990-01-01

This paper is the transcription of remarks made at the conclusion of the Workshop on Cold Neutron Sources held at the Los Angeles National Laboratory, Los Alamos, New Mexico, March 5--7, 1990. Areas of interest include the following: scattering functions; cold moderator materials; radiation mixing of chemical composition; comparison of some pulsed moderator spectra; hydrogen mixtures; premoderators and shields; composite reflectors; exotic moderator materials; deuterated methanes; mixed moderator materials; and test facility availabilities. 2 refs., 4 figs., 1 tab

Effects of actinide compositional variability in the US spent fuel inventory on partitioning-transmutation systems

International Nuclear Information System (INIS)

Ludwig, S.B.; Michaels, G.E.; Hanson, B.D.

1992-01-01

Partitioning and transmutation (P-T) is an advanced waste management concept by which certain undesirable nuclides in spent fuel are first isolated (partitioned) and later destroyed (transmuted) in a nuclear reactor or other transmutation device. There are wide variabilities in the nuclide composition of spent fuel. This implies that there will also be wide variabilities in the transmutation device feed. As a waste management system, P-T must be able to accept (all) spent fuel. Variability of nuclide composition (i.e., the feed material for transmutation devices) may be important because virtually all transmutation systems propose to configure transuranic (TRU) nuclides recovered from discharged lightwater reactor (LWR) spent fuel in critical or near-critical cores. To date, all transmutation system core analyses assume invariant nuclide concentrations for startup and recycle cores. Using the US Department of Energy's (DOE's) Characteristics Data Base (CDB) and the ORIGEN2 computer code, the current and projected spent fuel discharges until the year 2016 have been categorized according to combinations of fuel burnup, initial enrichment, fuel age (cooling time) and reactor type (boiling-water or pressurized-water reactors). The variability of the infinite multiplication factor (k ∞ ) is calculated for both fast (ALMR) and thermal (accelerator-based) transmuter systems

Methodology to estimate the threshold in-cylinder temperature for self-ignition of fuel during cold start of Diesel engines

International Nuclear Information System (INIS)

Broatch, A.; Ruiz, S.; Margot, X.; Gil, A.

2010-01-01

Cold startability of automotive direct injection (DI) Diesel engines is frequently one of the negative features when these are compared to their closest competitor, the gasoline engine. This situation worsens with the current design trends (engine downsizing) and the emerging new Diesel combustion concepts, such as HCCI, PCCI, etc., which require low compression ratio engines. To mitigate this difficulty, pre-heating systems (glow plugs, air heating, etc.) are frequently used and their technologies have been continuously developed. For the optimum design of these systems, the determination of the threshold temperature that the gas should have in the cylinder in order to provoke the self-ignition of the fuel injected during cold starting is crucial. In this paper, a novel methodology for estimating the threshold temperature is presented. In this methodology, experimental and computational procedures are adequately combined to get a good compromise between accuracy and effort. The measurements have been used as input data and boundary conditions in 3D and 0D calculations in order to obtain the thermodynamic conditions of the gas in the cylinder during cold starting. The results obtained from the study of two engine configurations -low and high compression ratio- indicate that the threshold in-cylinder temperature is a single temperature of about 415 o C.

Composition of diesl fuels from German refinery. Products of summer 2003; Zusammensetzung von Dieselkraftstoffen aus deutschen Raffinerien. Sommerware 2003

Energy Technology Data Exchange (ETDEWEB)

Froehling, J.C. [ARAL Forschung GmbH, Bochum (Germany)

2004-08-01

DGMK research project 583-1 investigates the composition of sulfur-free Diesel fuels as a supplement to DGMK report 583 published in 2002, which reports the composition of Diesel fuels with a sulfur content of max. 350 mg/kg. Thereby the effect of desulfurisation on the composition of Diesel fuels was determined. In summer 2003 fuels from German refineries were sampled and examined. In contrast to the first survey, the number of tests was reduced significantly. Only those parameters were considered that were likely to have changed due to the modified refining processes. Since sulfur-free products have to this extent been investigated for the first time, the results will give a significant contribution to questions regarding application techniques and ecology. (orig.)

Conceptual design of a commercial tokamak hybrid reactor fueling system

Energy Technology Data Exchange (ETDEWEB)

Matney, K.D.; Donnert, H.J.; Yang, T.F.

1979-12-01

A conceptual design of a fuel injection system for CTHR (Commercial Tokamak Hybrid Reactor) is discussed. Initially, relative merits of the cold-fueling concept are compared with those of the hot-fueling concept; that is, fueling where the electron is below 1 eV is compared with fueling where the electron temperature exceeds 100 eV. It is concluded that cold fueling seems to be somewhat more free of drawbacks than hot fueling. Possible implementation of the cold-fueling concept is exploited via frozen-pellet injection. Several methods of achieving frozen-pellet injection are discussed and the light-gas-gun approach is chosen from these possibilities. A modified version of the ORNL Neutral Gas Shielding Model is used to simulate the pellet injection process. From this simulation, the penetration-depth dependent velocity requirement is determined. Finally, with the velocity requirement known, a gas-pressure requirement for the proposed conceptual design is established. The cryogenic fuel-injection and fuel-handling systems are discussed. A possible way to implement the conceptual device is examined along with the attendant effects on the total system.

Conceptual design of a commercial tokamak hybrid reactor fueling system

International Nuclear Information System (INIS)

Matney, K.D.; Donnert, H.J.; Yang, T.F.

1979-12-01

A conceptual design of a fuel injection system for CTHR (Commercial Tokamak Hybrid Reactor) is discussed. Initially, relative merits of the cold-fueling concept are compared with those of the hot-fueling concept; that is, fueling where the electron is below 1 eV is compared with fueling where the electron temperature exceeds 100 eV. It is concluded that cold fueling seems to be somewhat more free of drawbacks than hot fueling. Possible implementation of the cold-fueling concept is exploited via frozen-pellet injection. Several methods of achieving frozen-pellet injection are discussed and the light-gas-gun approach is chosen from these possibilities. A modified version of the ORNL Neutral Gas Shielding Model is used to simulate the pellet injection process. From this simulation, the penetration-depth dependent velocity requirement is determined. Finally, with the velocity requirement known, a gas-pressure requirement for the proposed conceptual design is established. The cryogenic fuel-injection and fuel-handling systems are discussed. A possible way to implement the conceptual device is examined along with the attendant effects on the total system

Conceptual design of a commercial tokamak hybrid reactor fueling system

International Nuclear Information System (INIS)

Matney, K.D.; Donnert, H.J.; Yang, T.F.

1979-12-01

A conceptual design of a fuel injection system for CTHR (Commercial Tokamak Hybrid Reactor) is discussed. Initially, relative merits of the cold-fueling concept are compared with those of the hot-fueling concept; that is, fueling where the electron temperature is below 1 eV is compared with fueling where the electron temperature exceeds 100 eV. It is concluded that cold fueling seems to be somewhat more free of drawbacks than hot fueling. Possible implementation of the cold-fueling concept is exploited via frozen-pellet injection. Several methods of achieving frozen-pellet injection are discussed and the light-gas-gun approach is chosen from these possibilities. A modified version of the ORNL Neutral Gas Shielding Model is used to simulate the pellet injection process. From this simulation, the penetration-depth dependent velocity requirement is determined. Finally, with the velocity requirement known, a gas-pressure requirement for the proposed conceptual design is established. The cryogenic fuel-injection and fuel-handling systems are discussed. A possible way to implement the conceptual device is examined along with the attendant effects on the total system

Improvements to SFCOMPO - a database on isotopic composition of spent nuclear fuel

International Nuclear Information System (INIS)

Suyama, Kenya; Nouri, Ali; Mochizuki, Hiroki; Nomura, Yasushi

2003-01-01

Isotopic composition is one of the most relevant data to be used in the calculation of burnup of irradiated nuclear fuel. Since autumn 2002, the Organisation for Economic Co-operation and Development/Nuclear Energy Agency (OECD/NEA) has operated a database of isotopic composition - SFCOMPO, initially developed in Japan Atomic Energy Research Institute. This paper describes the latest version of SFCOMPO and the future development plan in OECD/NEA. (author)

Development of Innovative Accident Tolerant High Thermal Conductivity UO₂-Diamond Composite Fuel Pellets

Energy Technology Data Exchange (ETDEWEB)

Tulenko, James [Univ. of Florida, Gainesville, FL (United States); Subhash, Ghatu [Univ. of Florida, Gainesville, FL (United States)

2016-01-01

The University of Florida (UF) evaluated a composite fuel consisting of UO₂ powder mixed with diamond micro particles as a candidate as an accident-tolerant fuel (ATF). The research group had previous extensive experience researching with diamond micro particles as an addition to reactor coolant for improved plant thermal performance. The purpose of this research work was to utilize diamond micro particles to develop UO₂-Diamond composite fuel pellets with significantly enhanced thermal properties, beyond that already being measured in the previous UF research projects of UO₂ – SiC and UO₂ – Carbon Nanotube fuel pins. UF is proving with the current research results that the addition of diamond micro particles to UO₂ may greatly enhanced the thermal conductivity of the UO₂ pellets producing an accident-tolerant fuel. The Beginning of life benefits have been proven and fuel samples are being irradiated in the ATR reactor to confirm that the thermal conductivity improvements are still present under irradiation.

Creep rupture properties of solution annealed and cold worked type 316 stainless steel cladding tubes

International Nuclear Information System (INIS)

Mathew, M.D.; Latha, S.; Mannan, S.L.; Rodriguez, P.

1990-01-01

Austenitic stainless steels (mainly type 316 and its modifications) are used as fuel cladding materials in all current generation fast breeder reactors. For the Fast Breeder Test Reactor (FBTR) at Kalpakkam, modified type 316 stainless steel (SS) was chosen as the material for fuel cladding tubes. In order to evaluate the influence of cold work on the performance of the fuel element, the investigation was carried out on cladding tubes in three metallurgical conditions (solution annealed, ten percent cold worked and twenty percent cold worked). The results indicate that: (i) The creep strength of type 316 SS cladding tube increases with increasing cold work. (ii) The benificial effects of cold work are retained at almost all the test conditions investigated. (iii) The Larson Miller parameter analysis shows a two slope behaviour for 20PCW material suggesting that caution should be exercised in extrapolating the creep rupture life to stresses below 125 MPa. At very low stress levels, the LMP values fall below the values of the 10 PCW material. (author). 6 refs., 19 figs. , 10 tabs

Effect of chemistry variations on the short-term rupture life and tensile properties of 20% cold-worked type 316 stainless steel

International Nuclear Information System (INIS)

Duncan, D.R.; Paxton, M.M.

1977-01-01

The effects of compositional variations on the rupture life of 20% cold-worked Type 316 stainless steel were investigated at 19-ksi (131-MPa) uniaxial tensile stress and at 1400 0 F (1033 K). Forty-nine different alloys were studied, with compositional variations from nominal in carbon, nitrogen, phosphorus, sulfur, boron, manganese, copper, silicon, molybdenum, cobalt, chromium and nickel. This alloy and cold-work level represents the duct and fuel cladding material choice for the first four core loadings of the Fast Flux Test Facility, a key element in the Liquid-Metal Fast Breeder Reactor Program. Tensile properties of four of the alloys were studied at temperatures from room temperature to 1600 0 F (1144 K). Boron, nitrogen, and molybdenum plus silicon additions significantly increased rupture life, while chromium and carbon additions decreased rupture life. Molybdenum plus silicon additions increased yield and ultimate strength and ductility at 1200 0 F (922 K) and below

Balance and behavior of gaseous radionuclides released during initial PWR fuel reprocessing operations

International Nuclear Information System (INIS)

Leudet, A.; Miquel, P.; Goumondy, P.J.; Charrier, G.

1982-08-01

Five fuel pins, taken from a PWR fuel assembly with 32000 MWD/t burn-up were chopped and dissolved in leak-proof equipment designed for accurate determination of the composition and quantity of gaseous elements released in these operations. Analytical methods were specially developped to determine directly the noble gases, tritium and gaseous carbon compounds in the gas phase. Volatile iodine was kept as close as possible to the source by cold traps, then transferred to a caustic solution for quantitative analysis. The quantities and activities of gaseous fission products thus determined were compared with predicted values obtained through computation. Very good agreement was generally observed

Balance and behavior of gaseous radionuclides released during initial PWR fuel reprocessing operations

International Nuclear Information System (INIS)

Leudet, A.; Miquel, P.; Goumondy, P.J.; Charrier, G.

1983-01-01

Five fuel pins, taken from a PWR fuel assembly with 32,000 MwD/t burn-up were chopped and dissolved in leak-proof equipment designed for accurate determination of the composition and quantity of gaseous elements released in these operations. Analytical methods were specially developed to determine directly the noble gases, tritium and gaseous carbon compounds in the gas phase. Volatile iodine was kept as close as possible to the source by cold traps, then transferred to a caustic solution for quantitative analysis. The quantities and activities of gaseous fission products thus determined were compared with predicted values obtained through computation. Very good agreement was generally observed

Electrospun Nafion®/Polyphenylsulfone Composite Membranes for Regenerative Hydrogen Bromine Fuel Cells

Science.gov (United States)

Park, Jun Woo; Wycisk, Ryszard; Pintauro, Peter N.; Yarlagadda, Venkata; Van Nguyen, Trung

2016-01-01

The regenerative H2/Br2-HBr fuel cell, utilizing an oxidant solution of Br2 in aqueous HBr, shows a number of benefits for grid-scale electricity storage. The membrane-electrode assembly, a key component of a fuel cell, contains a proton-conducting membrane, typically based on the perfluorosulfonic acid (PFSA) ionomer. Unfortunately, the high cost of PFSA membranes and their relatively high bromine crossover are serious drawbacks. Nanofiber composite membranes can overcome these limitations. In this work, composite membranes were prepared from electrospun dual-fiber mats containing Nafion® PFSA ionomer for facile proton transport and an uncharged polymer, polyphenylsulfone (PPSU), for mechanical reinforcement, and swelling control. After electrospinning, Nafion/PPSU mats were converted into composite membranes by softening the PPSU fibers, through exposure to chloroform vapor, thus filling the voids between ionomer nanofibers. It was demonstrated that the relative membrane selectivity, referenced to Nafion® 115, increased with increasing PPSU content, e.g., a selectivity of 11 at 25 vol% of Nafion fibers. H2-Br2 fuel cell power output with a 65 μm thick membrane containing 55 vol% Nafion fibers was somewhat better than that of a 150 μm Nafion® 115 reference, but its cost advantage due to a four-fold decrease in PFSA content and a lower bromine species crossover make it an attractive candidate for use in H2/Br2-HBr systems. PMID:28773268

Electrospun Nafion®/Polyphenylsulfone Composite Membranes for Regenerative Hydrogen Bromine Fuel Cells

Directory of Open Access Journals (Sweden)

Jun Woo Park

2016-02-01

Full Text Available The regenerative H2/Br2-HBr fuel cell, utilizing an oxidant solution of Br2 in aqueous HBr, shows a number of benefits for grid-scale electricity storage. The membrane-electrode assembly, a key component of a fuel cell, contains a proton-conducting membrane, typically based on the perfluorosulfonic acid (PFSA ionomer. Unfortunately, the high cost of PFSA membranes and their relatively high bromine crossover are serious drawbacks. Nanofiber composite membranes can overcome these limitations. In this work, composite membranes were prepared from electrospun dual-fiber mats containing Nafion® PFSA ionomer for facile proton transport and an uncharged polymer, polyphenylsulfone (PPSU, for mechanical reinforcement, and swelling control. After electrospinning, Nafion/PPSU mats were converted into composite membranes by softening the PPSU fibers, through exposure to chloroform vapor, thus filling the voids between ionomer nanofibers. It was demonstrated that the relative membrane selectivity, referenced to Nafion® 115, increased with increasing PPSU content, e.g., a selectivity of 11 at 25 vol% of Nafion fibers. H2-Br2 fuel cell power output with a 65 μm thick membrane containing 55 vol% Nafion fibers was somewhat better than that of a 150 μm Nafion® 115 reference, but its cost advantage due to a four-fold decrease in PFSA content and a lower bromine species crossover make it an attractive candidate for use in H2/Br2-HBr systems.

Fuel composition effect on the electrostatically-driven atomization of bio-butanol containing engine fuel blends

International Nuclear Information System (INIS)

Agathou, Maria S.; Kyritsis, Dimitrios C.

2012-01-01

Highlights: ► Sprays of alcohol-containing blends are amenable to electrostatic manipulation. ► Monodispersion is non-achievable for conditions pertaining to automotive applications. ► Electrical conductivity and surface tension do not determine fully the spray behavior. ► Non-dimensional analysis was performed to classify flow regimes for each blend. ► We numbers revealed the possibility of droplet secondary break-up. - Abstract: Electrostatically assisted sprays of three fuel blends of bio-butanol, ethanol and heptane were studied experimentally. Mixture composition was selected such that electrical conductivity and surface tension were kept constant for all three mixtures. In this manner, the effect of fuel composition was investigated in a context that broadens the classical focus on the effective decrease of surface tension through the action of electrostatic fields. High-speed visualization was used in order to capture e-spray morphology. In addition, probability density functions of the e-spray droplet size and velocity were measured using Phase-Doppler Anemometry for a variety of flow rates and applied voltages. The dependence of droplet average diameter on both flow rate and applied electric field was highlighted. Polydisperse sprays were observed which was rationalized through the calculation of droplet Weber numbers that pointed to the possibility of a secondary droplet break-up.

Preparation and thermal performance of polystyrene/n-tetradecane composite nanoencapsulated cold energy storage phase change materials

International Nuclear Information System (INIS)

Fang, Yutang; Yu, Huimin; Wan, Weijun; Gao, Xuenong; Zhang, Zhengguo

2013-01-01

Highlights: • Average particle size of Tet/PS nanocapsules is smaller than the same type composite. • Latent heat of Tet/PS nanocapsules is as high as the same type composite. • Freeze–thaw cycle test and centrifugal sedimentation method are employed. • Tet/PS nanocapsules can be a candidate for cold thermal energy storage. - Abstract: In this paper, a novel polystyrene/n-tetradecane composite nanoencapsulated phase change material as latent functionally thermal fluid (LFTF) for cold thermal energy storage was synthesized by ultrasonic-assistant miniemulsion in situ polymerization. The morphology, chemical structure and thermal performances of the nanoencapsulated phase change material (NEPCM) were measured by particle size analyzer, transmission electron microscope (TEM), Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TG), respectively. The thermo-physical properties of the cool storage media were tested as well. The results showed that, a uniform spherical NEPCM with average diameter of 132 nm was prepared. The melting and freezing points and the latent heats of the NEPCMs was measured as 4.04 °C and −3.43 °C, 98.71 J g −1 and 91.27 J g −1 , respectively. The specific heat of its latex were determined as the maximum value of 4.822 J g −1 K −1 . The freeze–thaw cycle test indicated that the NEPCMs have good mechanical stability, and most capsules were still complete except some broken individuals from TEM images. Due to its good thermal properties and mechanical stability, the polystyrene/n-tetradecane NEPCM displays a good potential for cool energy storage

Spent fuel isotopic composition data base system on WWW. SFCOMPO on W3

International Nuclear Information System (INIS)

Suyama, Kenya

1997-11-01

Spent Fuel Composition Data Base System 'SFCOMPO' has been developed on IBM compatible PC. This data base system is not widely used, since users must purchase the data base software by themselves. 'SFCOMPO on W3' is a system to overcome this problem. User can search and visualize the data in the data base by accessing WWW server through the Internet from local machine. Only a browsing software to access WWW should be prepared. It enables us to easily search data of spent fuel composition if we can access the Internet. This system can be operated on WWW server machine which supports use of Common Gateway Interface (CGI). This report describes the background of the development of SFCOMPO on W3 and is it's user's manual. (author)

Variations in fluid chemistry and membrane phospholipid fatty acid composition of the bacterial community in a cold storage groundwater system during clogging events

International Nuclear Information System (INIS)

Vetter, Alexandra; Mangelsdorf, Kai; Wolfgramm, Markus; Rauppach, Kerstin; Schettler, Georg; Vieth-Hillebrand, Andrea

2012-01-01

In order to monitor the operating mode of the cold storage of the German Parliament (North German Basin) the fluid chemistry and the phospholipid fatty acid (PLFA) composition of the indigenous microbial community have been monitored from August 2006 to August 2009. During this time two periods of reduced injection (clogging events) characterized by Fe precipitates and microbial biofilms in filters occurred in the injection wells impairing the operating state of the investigated cold storage. The fluid monitoring revealed the presence of sufficient amounts of potential C and energy sources (e.g. DOC and SO 4 2- ) in the process water to sustain microbial life in the cold storage. In times of reduced injection the PLFA inventory of the microbial community differs significantly from times of normal operating phases indicating compositional changes in the indigenous microbial ecosystem. The most affected fatty acids (FAs) are 16:1ω7c (increase), 16:1ω7t (decrease) and 18:1ω7c (increase), interpreted to originate mainly from Fe and S oxidizers, as well as branched FA with 15, 16 and 17 C atoms (decrease) most likely representing sulfate-reducing bacteria (SRB). Based on this variability, PLFA ratios have been created to reflect the increasing dominance of biofilm forming S and Fe oxidizers during the disturbance periods. These ratios are potential diagnostic tools to assess the microbiological contribution to the clogging events and to find appropriate counteractive measures (e.g. mechanical cleaning vs disinfection). The correlation between changes in the PLFA composition and the operational state suggests that microbially mediated processes play a significant role in the observed clogging events in the investigated cold storage.

Lignocellulosic Composites Prepared Utilizing Aqueous Alkaline/Urea Solutions with Cold Temperatures

Directory of Open Access Journals (Sweden)

Brent Tisserat

2018-01-01

Full Text Available Lignocellulosic composites (LCs were fabricated by partially dissolving cotton to create a matrix that was reinforced with osage orange wood (OOW particles and/or blue agave fibers (AF. LCs were composed of 15–35% cotton matrix and 65–85% OWW/AF reinforcement. The matrix was produced by soaking cotton wool in a cold aqueous alkaline/urea solvent and was stirred for 15 minutes at 350 rpm to create a viscous gel. The gel was then reinforced with lignocellulosic components, mixed, and then pressed into a panel mold. LC panels were soaked in water to remove the aqueous solvent and then oven dried to obtain the final LC product. Several factors involved in the preparation of these LCs were examined including reaction temperatures (−5 to −15°C, matrix concentration (15–35% cotton, aqueous solvent volume (45–105 ml/panel, and the effectiveness of employing various aqueous solvent formulations. The mechanical properties of LCs were determined and reported. Conversion of the cotton into a suitable viscous gel was critical in order to obtain LCs that exhibited high mechanical properties. LCs with the highest mechanical properties were obtained when the cotton wools were subjected to a 4.6% LiOH/15% urea solvent at −12.5°C using an aqueous solvent volume of 60 ml/panel. Cotton wool subjected to excessive cold alkaline solvents volumes resulted in irreversible cellulose breakdown and a resultant LC that exhibited poor mechanical properties.

A comparison of the C{sub 2}-C{sub 9} hydrocarbon compositions of vehicle fuels and urban air in Dublin, Ireland

Energy Technology Data Exchange (ETDEWEB)

Broderick, B M; Marnane, I S [Trinity College, Dublin (Ireland). Dept. of Civil, Structural and Environmental Engineering

2002-07-01

Hourly roadside hydrocarbon concentrations were measured over a six-week period at a heavily trafficked junction in Dublin city centre. Samples of ten typical leaded and unleaded petrol fuels used in Irish vehicles were also collected and their hydrocarbon compositions determined. The measured ambient hydrocarbon concentrations are presented, as are the properties of each of the analysed fuels. Comparison of the ambient hydrocarbon concentrations and the fuel hydrocarbon composition reveals a strong correlation for most hydrocarbons, except those compounds that were wholly combustion derived (i.e. not present in the fuel). Different characteristics were noted for aromatics, alkanes and alkenes. The comparison of roadside ambient air and fuel hydrocarbon content agrees well with other studies that have compared fuel content and exhaust composition. The relative impacts of exhaust and evaporative emissions on roadside hydrocarbon concentrations are apparent. (Author)

Engine Cold Start

Science.gov (United States)

2015-09-01

matching pre- calibrated amplifier • BEI Shaft Encoder (0.2 CAD) • Wolff Instrumented Injector The high speed data was recorded and post-processed by...14. ABSTRACT These fuels were used for testing a GEP 6.5L turbocharged V-8 diesel engine operation in a cold box. This engine architecture is...Z39.18 UNCLASSIFIED UNCLASSIFIED v EXECUTIVE SUMMARY A fuel’s cetane number is very important for the operation of modern diesel

Composition and Distribution of Tramp Uranium Contamination on BWR and PWR Fuel Rods

International Nuclear Information System (INIS)

Schienbein, Marcel; Zeh, Peter; Hurtado, Antonio; Rosskamp, Matthias; Mailand, Irene; Bolz, Michael

2012-09-01

In a joint research project of VGB and AREVA NP GmbH the behaviour of alpha nuclides in nuclear power plants with light water reactors has been investigated. Understanding the source and the behaviour of alpha nuclides is of big importance for planning radiation protection measures for outages and upcoming dismantling projects. Previous publications have shown the correlation between plant specific alpha contamination of the core and the so called 'tramp fuel' or 'tramp uranium' level which is linked to the defect history of fuel assemblies and accordingly the amount of previously washed out fuel from defective fuel rods. The methodology of tramp fuel estimation is based on fission product concentrations in reactor coolant but also needs a good knowledge of tramp fuel composition and in-core distribution on the outer surface of fuel rods itself. Sampling campaigns of CRUD deposits of irradiated fuel assemblies in different NPPs were performed. CRUD analyses including nuclide specific alpha analysis have shown systematic differences between BWR and PWR plants. Those data combined with literature results of fuel pellet investigations led to model improvements showing that a main part of fission products is caused by fission of Pu-239 an activation product of U-238. CRUD investigations also gave a better picture of the in-core composition and distribution of the tramp uranium contamination. It was shown that the tramp uranium distribution in PWR plants is time dependent. Even new fuel assemblies will be notably contaminated after only one cycle of operation. For PWR applies the following logic: the higher the local power the higher the contamination. With increasing burnup the local rod power usually decreases leading to decreasing tramp uranium contamination on the fuel rod surface. This is not applicable for tramp uranium contamination in BWR. CRUD contamination (including the tramp fuel deposits) is much more fixed and is constantly increasing

Multidisciplinary Simulation of Graphite-Composite and Cermet Fuel Elements for NTP Point of Departure Designs

Science.gov (United States)

Stewart, Mark E.; Schnitzler, Bruce G.

2015-01-01

This paper compares the expected performance of two Nuclear Thermal Propulsion fuel types. High fidelity, fluid/thermal/structural + neutronic simulations help predict the performance of graphite-composite and cermet fuel types from point of departure engine designs from the Nuclear Thermal Propulsion project. Materials and nuclear reactivity issues are reviewed for each fuel type. Thermal/structural simulations predict thermal stresses in the fuel and thermal expansion mis-match stresses in the coatings. Fluid/thermal/structural/neutronic simulations provide predictions for full fuel elements. Although NTP engines will utilize many existing chemical engine components and technologies, nuclear fuel elements are a less developed engine component and introduce design uncertainty. Consequently, these fuel element simulations provide important insights into NTP engine performance.

Coating Properties of WC-Ni Cold Spray Coating for the Application in Secondary Piping System of Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Kim, JeongWon; Kim, Seunghyun; Kim, Ji Hyun [UNIST, Ulsan (Korea, Republic of)

2015-10-15

As a result of FAC(flow accelerated corrosion), severe accidents, failure of carbon steel like a Mihama Unit-3 occurred. Chemical composition change of carbon steel or coating to inner surface is one of methods to improve corrosion properties. Among them, thermal spray coating is convenient solution to apply at industry. Powder is melted at blast furnace and ejected to substrate. After adhesion, substrate and coating layer is cooled down and coated layer protects steel from corrosion finally. However high thermal energy is transferred to substrate and coating layer so it leads high thermal residual stress in coating procedure. Besides, high temperature for melting powder makes unexpected chemical reaction of powder like an oxidation or carburization. Whereas, cold spray uses low temperature comparing with other thermal spray. Thermal energy is used for not melting powder but high kinetic energy of powder and plastic deformation during collision. Therefore, fuel such as oxygen-acetylene gas is not needed. It needs carrier gas, compressed air, nitrogen or helium, to increase kinetic energy of powder and move powder to substrate. Comparing cold spray with high velocity oxy fuel (HVOF), one of thermal spray, cold spray coating layer contains only WC and Co. One of other problem about WC is brittleness during coating. To improve deformability of WC, binder metal is added. For example, Co, Cr, Ni, Cu, Al, Fe or etc. Additionally, binder metal lowering melting temperature of composite powder increases coating properties. Among them, Co which is widely used as binder metal maintains mechanical properties like a hardness and improves corrosion properties. Therefore Co is not suitable for binder metal of WC coating. In contrast, Ni has better corrosion resistance to alkaline environment and makes lower melting temperature. Moreover, in a view of cold spray, FCC structure has better deformability than BCC or HCP, and BCC has lowest deformability. WC is BCC structure so it

Method for forming nuclear fuel containers of a composite construction and the product thereof

International Nuclear Information System (INIS)

Cheng, B.-C.; Rosenbaum, H.S.; Armijo, J.S.

1981-01-01

An improved method of producing a composite nuclear fuel container is described which comprises a casing or fuel sheath of zirconium or its alloy with a lining cladding of deposited copper superimposed over the inside surface of the zirconium or alloy and a layer of oxide of the zirconium or alloy formed on the inside surface of the casing or sheath. (U.K.)

Impact of Alternative Jet Fuels on Engine Exhaust Composition During the 2015 ECLIF Ground-Based Measurements Campaign.

Science.gov (United States)

Schripp, Tobias; Anderson, Bruce; Crosbie, Ewan C; Moore, Richard H; Herrmann, Friederike; Oßwald, Patrick; Wahl, Claus; Kapernaum, Manfred; Köhler, Markus; Le Clercq, Patrick; Rauch, Bastian; Eichler, Philipp; Mikoviny, Tomas; Wisthaler, Armin

2018-04-17

The application of fuels from renewable sources ("alternative fuels") in aviation is important for the reduction of anthropogenic carbon dioxide emissions, but may also attribute to reduced release of particles from jet engines. The present experiment describes ground-based measurements in the framework of the ECLIF (Emission and Climate Impact of Alternative Fuels) campaign using an Airbus A320 (V2527-A5 engines) burning six fuels of chemically different composition. Two reference Jet A-1 with slightly different chemical parameters were applied and further used in combination with a Fischer-Tropsch synthetic paraffinic kerosene (FT-SPK) to prepare three semi synthetic jet fuels (SSJF) of different aromatic content. In addition, one commercially available fully synthetic jet fuel (FSJF) featured the lowest aromatic content of the fuel selection. Neither the release of nitrogen oxide or carbon monoxide was significantly affected by the different fuel composition. The measured particle emission indices showed a reduction up to 50% (number) and 70% (mass) for two alternative jet fuels (FSJF, SSJF2) at low power settings in comparison to the reference fuels. The reduction is less pronounced at higher operating conditions but the release of particle number and particle mass is still significantly lower for the alternative fuels than for both reference fuels. The observed correlation between emitted particle mass and fuel aromatics is not strict. Here, the H/C ratio is a better indicator for soot emission.

Fabrication technology of spherical fuel element for HTR-10

International Nuclear Information System (INIS)

He Jun; Zou Yanwen; Liang Tongxiang; Qiu Xueliang

2002-01-01

R and D on the fabrication technology of the spherical fuel elements for the 10 MW HTR Test Module (HTR-10) began from 1986. Cold quasi-isostatic molding with a silicon rubber die is used for manufacturing the spherical fuel elements.The fabrication technology and the graphite matrix materials were investigated and optimized. Twenty five batches of fuel elements, about 11000 of the fuel elements, have been produced. The cold properties of the graphite matrix materials satisfied the design specifications. The mean free uranium fraction of 25 batches was 5 x 10 -5

Release to the Gas Phase of Inorganic Elements during Wood Combustion. Part 2: Influence of Fuel Composition

DEFF Research Database (Denmark)

van Lith, Simone Cornelia; Jensen, Peter Arendt; Frandsen, Flemming

2008-01-01

temperatures in the range of 500–1150 °C in a laboratory-scale tube reactor and by performing mass balance calculations based on the weight measurements and chemical analyses of the wood fuels and the residual ash samples. Four wood fuels with different ash contents and inorganic compositions were investigated...... of the alkali metals K and Na was, however, strongly dependent on both the temperature and the fuel composition under the investigated conditions. The release of the heavy metals Zn and Pb started around 500 °C and increased sharply to more than 85% at 850 °C in the case of spruce, beech, and bark...

Cold exposure affects carbohydrates and lipid metabolism, and induces Hog1p phosphorylation in Dekkera bruxellensis strain CBS 2499.

Science.gov (United States)

Galafassi, Silvia; Toscano, Marco; Vigentini, Ileana; Zambelli, Paolo; Simonetti, Paolo; Foschino, Roberto; Compagno, Concetta

2015-05-01

Dekkera bruxellensis is a yeast known to affect the quality of wine and beer. This species, due to its high ethanol and acid tolerance, has been reported also to compete with Saccharomyces cerevisiae in distilleries producing fuel ethanol. In order to understand how this species responds when exposed to low temperatures, some mechanisms like synthesis and accumulation of intracellular metabolites, changes in lipid composition and activation of the HOG-MAPK pathway were investigated in the genome sequenced strain CBS 2499. We show that cold stress caused intracellular accumulation of glycogen, but did not induce accumulation of trehalose and glycerol. The cellular fatty acid composition changed after the temperature downshift, and a significant increase of palmitoleic acid was observed. RT-PCR analysis revealed that OLE1 encoding for Δ9-fatty acid desaturase was up-regulated, whereas TPS1 and INO1 didn't show changes in their expression. In D. bruxellensis Hog1p was activated by phosphorylation, as described in S. cerevisiae, highlighting a conserved role of the HOG-MAP kinase signaling pathway in cold stress response.

Cumulative damage fraction design approach for LMFBR metallic fuel elements

International Nuclear Information System (INIS)

Johnson, D.L.; Einziger, R.E.; Huchman, G.D.

1979-01-01

The cumulative damage fraction (CDF) analytical technique is currently being used to analyze the performance of metallic fuel elements for proliferation-resistant LMFBRs. In this technique, the fraction of the total time to rupture of the cladding is calculated as a function of the thermal, stress, and neutronic history. Cladding breach or rupture is implied by CDF = 1. Cladding wastage, caused by interactions with both the fuel and sodium coolant, is assumed to uniformly thin the cladding wall. The irradiation experience of the EBR-II Mark-II driver fuel with solution-annealed Type 316 stainless steel cladding provides an excellent data base for testing the applicability of the CDF technique to metallic fuel. The advanced metal fuels being considered for use in LMFBRs are U-15-Pu-10Zr, Th-20Pu and Th-2OU (compositions are given in weight percent). The two cladding alloys being considered are Type 316 stainless steel and a titanium-stabilized Type 316 stainless steel. Both are in the cold-worked condition. The CDF technique was applied to these fuels and claddings under the assumed steady-state operating conditions

Fuel containment, lightning protection and damage tolerance in large composite primary aircraft structures

Science.gov (United States)

Griffin, Charles F.; James, Arthur M.

1985-01-01

The damage-tolerance characteristics of high strain-to-failure graphite fibers and toughened resins were evaluated. Test results show that conventional fuel tank sealing techniques are applicable to composite structures. Techniques were developed to prevent fuel leaks due to low-energy impact damage. For wing panels subjected to swept stroke lightning strikes, a surface protection of graphite/aluminum wire fabric and a fastener treatment proved effective in eliminating internal sparking and reducing structural damage. The technology features developed were incorporated and demonstrated in a test panel designed to meet the strength, stiffness, and damage tolerance requirements of a large commercial transport aircraft. The panel test results exceeded design requirements for all test conditions. Wing surfaces constructed with composites offer large weight savings if design allowable strains for compression can be increased from current levels.

Spent fuel isotopic composition data base system on WWW. SFCOMPO on W3

Energy Technology Data Exchange (ETDEWEB)

Suyama, Kenya [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1997-11-01

Spent Fuel Composition Data Base System `SFCOMPO` has been developed on IBM compatible PC. This data base system is not widely used, since users must purchase the data base software by themselves. `SFCOMPO on W3` is a system to overcome this problem. User can search and visualize the data in the data base by accessing WWW server through the Internet from local machine. Only a browsing software to access WWW should be prepared. It enables us to easily search data of spent fuel composition if we can access the Internet. This system can be operated on WWW server machine which supports use of Common Gateway Interface (CGI). This report describes the background of the development of SFCOMPO on W3 and is it`s user`s manual. (author)

Laminated exfoliated graphite composite-metal compositions for fuel cell flow field plate or bipolar plate applications

Science.gov (United States)

Zhamu, Aruna; Shi, Jinjun; Guo, Jiusheng; Jang, Bor Z

2014-05-20

An electrically conductive laminate composition for fuel cell flow field plate or bipolar plate applications. The laminate composition comprises at least a thin metal sheet having two opposed exterior surfaces and a first exfoliated graphite composite sheet bonded to the first of the two exterior surfaces of the metal sheet wherein the exfoliated graphite composite sheet comprises: (a) expanded or exfoliated graphite and (b) a binder or matrix material to bond the expanded graphite for forming a cohered sheet, wherein the binder or matrix material is between 3% and 60% by weight based on the total weight of the first exfoliated graphite composite sheet. Preferably, the first exfoliated graphite composite sheet further comprises particles of non-expandable graphite or carbon in the amount of between 3% and 60% by weight based on the total weight of the non-expandable particles and the expanded graphite. Further preferably, the laminate comprises a second exfoliated graphite composite sheet bonded to the second surface of the metal sheet to form a three-layer laminate. Surface flow channels and other desired geometric features can be built onto the exterior surfaces of the laminate to form a flow field plate or bipolar plate. The resulting laminate has an exceptionally high thickness-direction conductivity and excellent resistance to gas permeation.

Development of composite membranes of PVA-TEOS doped KOH for alkaline membrane fuel cell

International Nuclear Information System (INIS)

Haryadi,; Sugianto, D.; Ristopan, E.

2015-01-01

Anion exchange membranes (AEMs) play an important role in separating fuel and oxygen (or air) in the Alkaline Membrane Fuel Cells. Preparation of hybrid organic inorganic materials of Polyvinylalcohol (PVA) - Tetraethylorthosilicate (TEOS) composite membrane doped KOH for direct alcohol alkaline fuel cell application has been investigated. The sol-gel method has been used to prepare the composite membrane of PVA-TEOS through crosslinking step and catalyzed by concentrated of hydrochloric acid. The gel solution was cast on the membrane plastic plate to obtain membrane sheets. The dry membranes were then doped by immersing in various concentrations of KOH solutions for about 4 hours. Investigations of the cross-linking process and the presence of hydroxyl group were conducted by FTIR as shown for frequency at about 1600 cm −1 and 3300 cm −1 respectively. The degree of swelling in ethanol decreased as the KOH concentration for membrane soaking process increased. The ion exchange capacity (IEC) of the membrane was 0.25meq/g. This composite membranes display significant ionic conductivity of 3.23 x 10 −2 S/cm in deionized water at room temperature. In addition, the morphology observation by scanning electron microscope (SEM) of the membrane indicates that soaking process of membrane in KOH increased thermal resistant

Development of composite membranes of PVA-TEOS doped KOH for alkaline membrane fuel cell

Science.gov (United States)

Haryadi, Sugianto, D.; Ristopan, E.

2015-12-01

Anion exchange membranes (AEMs) play an important role in separating fuel and oxygen (or air) in the Alkaline Membrane Fuel Cells. Preparation of hybrid organic inorganic materials of Polyvinylalcohol (PVA) - Tetraethylorthosilicate (TEOS) composite membrane doped KOH for direct alcohol alkaline fuel cell application has been investigated. The sol-gel method has been used to prepare the composite membrane of PVA-TEOS through crosslinking step and catalyzed by concentrated of hydrochloric acid. The gel solution was cast on the membrane plastic plate to obtain membrane sheets. The dry membranes were then doped by immersing in various concentrations of KOH solutions for about 4 hours. Investigations of the cross-linking process and the presence of hydroxyl group were conducted by FTIR as shown for frequency at about 1600 cm-1 and 3300 cm-1 respectively. The degree of swelling in ethanol decreased as the KOH concentration for membrane soaking process increased. The ion exchange capacity (IEC) of the membrane was 0.25meq/g. This composite membranes display significant ionic conductivity of 3.23 x 10-2 S/cm in deionized water at room temperature. In addition, the morphology observation by scanning electron microscope (SEM) of the membrane indicates that soaking process of membrane in KOH increased thermal resistant.

Development of composite membranes of PVA-TEOS doped KOH for alkaline membrane fuel cell

Energy Technology Data Exchange (ETDEWEB)

Haryadi,, E-mail: haryadi@polban.ac.id; Sugianto, D.; Ristopan, E. [Department of Chemical Engineering, Politeknik Negeri Bandung Jl. Gegerkalong Hilir, Ds. Ciwaruga, Bandung West Java (Indonesia)

2015-12-29

Anion exchange membranes (AEMs) play an important role in separating fuel and oxygen (or air) in the Alkaline Membrane Fuel Cells. Preparation of hybrid organic inorganic materials of Polyvinylalcohol (PVA) - Tetraethylorthosilicate (TEOS) composite membrane doped KOH for direct alcohol alkaline fuel cell application has been investigated. The sol-gel method has been used to prepare the composite membrane of PVA-TEOS through crosslinking step and catalyzed by concentrated of hydrochloric acid. The gel solution was cast on the membrane plastic plate to obtain membrane sheets. The dry membranes were then doped by immersing in various concentrations of KOH solutions for about 4 hours. Investigations of the cross-linking process and the presence of hydroxyl group were conducted by FTIR as shown for frequency at about 1600 cm{sup −1} and 3300 cm{sup −1} respectively. The degree of swelling in ethanol decreased as the KOH concentration for membrane soaking process increased. The ion exchange capacity (IEC) of the membrane was 0.25meq/g. This composite membranes display significant ionic conductivity of 3.23 x 10{sup −2} S/cm in deionized water at room temperature. In addition, the morphology observation by scanning electron microscope (SEM) of the membrane indicates that soaking process of membrane in KOH increased thermal resistant.

Fuel containment and damage tolerance in large composite primary aircraft structures. Phase 2: Testing

Science.gov (United States)

Sandifer, J. P.; Denny, A.; Wood, M. A.

1985-01-01

Technical issues associated with fuel containment and damage tolerance of composite wing structures for transport aircraft were investigated. Material evaluation tests were conducted on two toughened resin composites: Celion/HX1504 and Celion/5245. These consisted of impact, tension, compression, edge delamination, and double cantilever beam tests. Another test series was conducted on graphite/epoxy box beams simulating a wing cover to spar cap joint configuration of a pressurized fuel tank. These tests evaluated the effectiveness of sealing methods with various fastener types and spacings under fatigue loading and with pressurized fuel. Another test series evaluated the ability of the selected coatings, film, and materials to prevent fuel leakage through 32-ply AS4/2220-1 laminates at various impact energy levels. To verify the structural integrity of the technology demonstration article structural details, tests were conducted on blade stiffened panels and sections. Compression tests were performed on undamaged and impacted stiffened AS4/2220-1 panels and smaller element tests to evaluate stiffener pull-off, side load and failsafe properties. Compression tests were also performed on panels subjected to Zone 2 lightning strikes. All of these data were integrated into a demonstration article representing a moderately loaded area of a transport wing. This test combined lightning strike, pressurized fuel, impact, impact repair, fatigue and residual strength.

Interim report spent nuclear fuel retrieval system fuel handling development testing

Energy Technology Data Exchange (ETDEWEB)

Ketner, G.L.; Meeuwsen, P.V.; Potter, J.D.; Smalley, J.T.; Baker, C.P.; Jaquish, W.R.

1997-06-01

Fuel handling development testing was performed in support of the Fuel Retrieval System (FRS) Sub-Project at the Hanford Site. The project will retrieve spent nuclear fuel, clean and remove fuel from canisters, repackage fuel into baskets, and load fuel into a multi-canister overpack (MCO) for vacuum drying and interim dry storage. The FRS is required to retrieve basin fuel canisters, clean fuel elements sufficiently of uranium corrosion products (or sludge), empty fuel from canisters, sort debris and scrap from whole elements, and repackage fuel in baskets in preparation for MCO loading. The purpose of fuel handling development testing was to examine the systems ability to accomplish mission activities, optimization of equipment layouts for initial process definition, identification of special needs/tools, verification of required design changes to support performance specification development, and validation of estimated activity times/throughput. The test program was set up to accomplish this purpose through cold development testing using simulated and prototype equipment; cold demonstration testing using vendor expertise and systems; and graphical computer modeling to confirm feasibility and throughput. To test the fuel handling process, a test mockup that represented the process table was fabricated and installed. The test mockup included a Schilling HV series manipulator that was prototypic of the Schilling Hydra manipulator. The process table mockup included the tipping station, sorting area, disassembly and inspection zones, fuel staging areas, and basket loading stations. The test results clearly indicate that the Schilling Hydra arm cannot effectively perform the fuel handling tasks required unless it is attached to some device that can impart vertical translation, azimuth rotation, and X-Y translation. Other test results indicate the importance of camera locations and capabilities, and of the jaw and end effector tool design. 5 refs., 35 figs., 3 tabs.

Cold, clumpy accretion onto an active supermassive black hole.

Science.gov (United States)

Tremblay, Grant R; Oonk, J B Raymond; Combes, Françoise; Salomé, Philippe; O'Dea, Christopher P; Baum, Stefi A; Voit, G Mark; Donahue, Megan; McNamara, Brian R; Davis, Timothy A; McDonald, Michael A; Edge, Alastair C; Clarke, Tracy E; Galván-Madrid, Roberto; Bremer, Malcolm N; Edwards, Louise O V; Fabian, Andrew C; Hamer, Stephen; Li, Yuan; Maury, Anaëlle; Russell, Helen R; Quillen, Alice C; Urry, C Megan; Sanders, Jeremy S; Wise, Michael W

2016-06-09

Supermassive black holes in galaxy centres can grow by the accretion of gas, liberating energy that might regulate star formation on galaxy-wide scales. The nature of the gaseous fuel reservoirs that power black hole growth is nevertheless largely unconstrained by observations, and is instead routinely simplified as a smooth, spherical inflow of very hot gas. Recent theory and simulations instead predict that accretion can be dominated by a stochastic, clumpy distribution of very cold molecular clouds--a departure from the 'hot mode' accretion model--although unambiguous observational support for this prediction remains elusive. Here we report observations that reveal a cold, clumpy accretion flow towards a supermassive black hole fuel reservoir in the nucleus of the Abell 2597 Brightest Cluster Galaxy (BCG), a nearby (redshift z = 0.0821) giant elliptical galaxy surrounded by a dense halo of hot plasma. Under the right conditions, thermal instabilities produce a rain of cold clouds that fall towards the galaxy's centre, sustaining star formation amid a kiloparsec-scale molecular nebula that is found at its core. The observations show that these cold clouds also fuel black hole accretion, revealing 'shadows' cast by the molecular clouds as they move inward at about 300 kilometres per second towards the active supermassive black hole, which serves as a bright backlight. Corroborating evidence from prior observations of warmer atomic gas at extremely high spatial resolution, along with simple arguments based on geometry and probability, indicate that these clouds are within the innermost hundred parsecs of the black hole, and falling closer towards it.

Spent fuel composition database system on WWW. SFCOMPO on WWW Ver.2

International Nuclear Information System (INIS)

Mochizuki, Hiroki; Suyama, Kenya; Nomura, Yasushi; Okuno, Hiroshi

2001-08-01

'SFCOMPO on WWW Ver.2' is an advanced version of 'SFCOMPO on WWW (Spent Fuel Composition Database System on WWW' released in 1997. This new version has a function of database management by an introduced relational database software 'PostgreSQL' and has various searching methods. All of the data required for the calculation of isotopic composition is available from the web site of this system. This report describes the outline of this system and the searching method using Internet. In addition, the isotopic composition data and the reactor data of the 14 LWRs (7 PWR and 7 BWR) registered in this system are described. (author)

Improvement of the cold flow characteristics of biodiesel containing dissolved polymer wastes using acetone

Directory of Open Access Journals (Sweden)

Pouya Mohammadi

2014-03-01

Full Text Available Due to the fast fossil fuel depletion and at the same time global warming phenomenon anticipated for the next coming years, the necessity of developing alternative fuels e.g. biofuels (i.e. bioethanol, biodiesel, biogas and etc. has turned into an important concern. Recently, the application of the bio-solvency properties of biodiesel for recycling waste polymers has been highlighted. However, the impact of polymer dissolution on cold flow characteristics of biodiesel was never investigated. The present study was set to explore the impact of different solvents in stabilizing biodiesel-polymer solution. Among them, acetone was proved to be the best fuel stabilizer. Subsequently, cold flow characteristic i.e. cloud point, of the biodiesel-polymer-acetone fuel was found to have improved (decreased due to the inclusion of acetone. Finally, flash point analysis of the fuel blends containing acetone was done to ensured high safety of the fuel blend by dramatically increasing the flash point values of biodiesel-polymer fuel blends.

Proton conductive montmorillonite-Nafion composite membranes for direct ethanol fuel cells

International Nuclear Information System (INIS)

Wu, Xiu-Wen; Wu, Nan; Shi, Chun-Qing; Zheng, Zhi-Yuan; Qi, Hong-Bin; Wang, Ya-Fang

2016-01-01

Highlights: • Composite membranes are prepared with different montmorillonites and nafion solution. • Proton conductivities of the composite membranes are between 36.0 mS/cm and 38.5 mS/cm. • Ethanol permeability is between 0.69 × 10"−"6 cm"2/s and 2.67 × 10"−"6 cm"2/s. • Water uptake is approximately 24.30 mass%. - Abstract: The preparation of Nafion membranes modified with montmorillonites is less studied, and most relative works mainly applied in direct methanol fuel cells, less in direct ethanol fuel cells. Organic/inorganic composite membranes are prepared with different montmorillonites (Ca-montmorillonite, Na-montmorillonite, K-montmorillonite, Mg-montmorillonite, and H-montmorillonite) and Nafion solution via casting method at 293 K in air, and with balance of their proton conductivity and ethanol permeability. The ethanol permeability and proton conductivity of the membranes are comparatively studied. The montmorillonites can well decrease the ethanol permeability of the membranes via inserted them in the membranes, while less decrease the proton conductivities of the membranes depending on the inserted amount and type of montmorillonites. The proton conductivities of the membranes are between 36.0 mS/cm and 38.5 mS/cm. The ethanol permeability of the membranes is between 0.69 × 10"−"6 cm"2/s and 2.67 × 10"−"6 cm"2/s.

Development of cesium phosphotungstate salt and chitosan composite membrane for direct methanol fuel cells.

Science.gov (United States)

Xiao, Yanxin; Xiang, Yan; Xiu, Ruijie; Lu, Shanfu

2013-10-15

A novel composite membrane has been developed by doping cesium phosphotungstate salt (CsxH3-xPW12O40 (0≤x≤3), Csx-PTA) into chitosan (CTS/Csx-PTA) for application in direct methanol fuel cells (DMFCs). Uniform distribution of Csx-PTA nanoparticles has been achieved in the chitosan matrix. The proton conductivity of the composite membrane is significantly affected by the Csx-PTA content in the composite membrane as well as the Cs substitution in PTA. The highest proton conductivity for the CTS/Csx-PTA membranes was obtained with x=2 and Cs2-PTA content of 5 wt%. The value is 6×10(-3) S cm(-1) and 1.75×10(-2) S cm(-1) at 298 K and 353 K, respectively. The methanol permeability of CTS/Cs2-PTA membrane is about 5.6×10(-7), 90% lower than that of Nafion-212 membrane. The highest selectivity factor (φ) was obtained on CTS/Cs2-PTA-5 wt% composite membrane, 1.1×10(4)/Scm(-3)s. The present study indicates the promising potential of CTS/Csx-PTA composite membrane as alternative proton exchange membranes in direct methanol fuel cells. Copyright © 2013 Elsevier Ltd. All rights reserved.

Tensile behavior of humid aged advanced composites for helicopter external fuel tank development

Directory of Open Access Journals (Sweden)

Condruz Mihaela

2018-01-01

Full Text Available Influence of humid aging on tensile properties of two polymeric composites was studied. The purpose of the study was to evaluate the suitability of the materials for a naval helicopter external fuel tank. Due to the application, the humid environment was kerosene and saline solution to evaluate the sea water effect on the composite tensile strength. The composite samples were immersed in kerosene for 168 hours, respective 1752 hours and in saline solution for 168 hours. Tensile tests were performed after the immersion. The composite sample tensile tests showed that kerosene and saline solution had no influence on the elastic modulus of the materials, but it was observed a slight improvement of the tensile strength of the two polymeric composites.

Gas fired boilers: Perspective for near future fuel composition and impact on burner design process

Science.gov (United States)

Schiro, Fabio; Stoppato, Anna; Benato, Alberto

2017-11-01

The advancements on gas boiler technology run in parallel with the growth of renewable energy production. The renewable production will impact on the fuel gas quality, since the gas grid will face an increasing injection of alternative fuels (biogas, biomethane, hydrogen). Biogas allows producing energy with a lower CO2 impact; hydrogen production by electrolysis can mitigate the issues related to the mismatch between energy production by renewable and energy request. These technologies will contribute to achieve the renewable production targets, but the impact on whole fuel gas production-to-consumption chain must be evaluated. In the first part of this study, the Authors present the future scenario of the grid gas composition and the implications on gas fed appliances. Given that the widely used premixed burners are currently designed mainly by trial and error, a broader fuel gas quality range means an additional hitch on this design process. A better understanding and structuring of this process is helpful for future appliance-oriented developments. The Authors present an experimental activity on a premixed condensing boiler setup. A test protocol highlighting the burners' flexibility in terms of mixture composition is adopted and the system fuel flexibility is characterized around multiple reference conditions.

Gas fired boilers: Perspective for near future fuel composition and impact on burner design process

Directory of Open Access Journals (Sweden)

Schiro Fabio

2017-01-01

Full Text Available The advancements on gas boiler technology run in parallel with the growth of renewable energy production. The renewable production will impact on the fuel gas quality, since the gas grid will face an increasing injection of alternative fuels (biogas, biomethane, hydrogen. Biogas allows producing energy with a lower CO2 impact; hydrogen production by electrolysis can mitigate the issues related to the mismatch between energy production by renewable and energy request. These technologies will contribute to achieve the renewable production targets, but the impact on whole fuel gas production-to-consumption chain must be evaluated. In the first part of this study, the Authors present the future scenario of the grid gas composition and the implications on gas fed appliances. Given that the widely used premixed burners are currently designed mainly by trial and error, a broader fuel gas quality range means an additional hitch on this design process. A better understanding and structuring of this process is helpful for future appliance-oriented developments. The Authors present an experimental activity on a premixed condensing boiler setup. A test protocol highlighting the burners' flexibility in terms of mixture composition is adopted and the system fuel flexibility is characterized around multiple reference conditions.

Some implications of batch average burnup calculations on predicted spent fuel compositions

International Nuclear Information System (INIS)

Alexander, C.W.; Croff, A.G.

1984-01-01

The accuracy of using batch-averaged burnups to determine spent fuel characteristics (such as isotopic composition, activity, etc.) was examined for a typical pressurized-water reactor (PWR) fuel discharge batch by comparing characteristics computed by (a) performing a single depletion calculation using the average burnup of the spent fuel and (b) performing separate depletion calculations based on the relative amounts of spent fuel in each of twelve burnup ranges and summing the results. The computations were done using ORIGEN 2. Procedure (b) showed a significant shift toward a greater quantity of the heavier transuranics, which derive from multiple neutron captures, and a corresponding decrease in the amounts of lower transuranics. Those characteristics which derive primarily from fission products, such as total radioactivity and total thermal power, are essentially identical for the two procedures. Those characteristics that derive primarily from the heavier transuranics, such as spontaneous fission neutrons, are underestimated by procedure (a)

A study on the criticality search of transuranium recycling BWR core by adjusting supplied fuel composition in equilibrium state

International Nuclear Information System (INIS)

Seino, Takeshi; Sekimoto, Hiroshi

1998-01-01

There have been some difficulties in carrying out an extensive evaluation of the equilibrium state of Light Water Reactor (LWR) recycling operations keeping their fixed criticality condition using conventional design codes because of the complexity of their calculation model for practical fuel and core design and because of a large amount of calculation time. This study presents an efficient approach to secure the criticality in an equilibrium cycle by adjusting a supplied fuel composition. The criticality search is performed by the use of fuel importance obtained from the equation adjoint to a continuously fuel supplied core burnup equation. Using this method, some numerical analyses were carried out in order to evaluate the mixed oxide (MOX) fuel composition of equilibrium Boiling Water Reactor (BWR) cores satisfying the criticality requirement. The results showed the comprehensive and quantitative characteristics on the equilibrium cores confining transuraniums for different MOX fuel loading fractions and irradiating conditions

Novel composite membranes based on PBI and dicationic ionic liquids for high temperature polymer electrolyte membrane fuel cells

International Nuclear Information System (INIS)

Hooshyari, Khadijeh; Javanbakht, Mehran; Adibi, Mina

2016-01-01

Two types of innovative composite membranes based on polybenzimidazole (PBI) containing dicationic ionic liquid 1,3-di(3-methylimidazolium) propane bis (trifluoromethylsulfonyl) imide (PDC 3 ) and monocationic ionic liquid 1-hexyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide (PMC 6 ) are prepared as electrolyte for high temperature fuel cells applications under anhydrous conditions. The analyses of results display promising characteristics such as high proton conductivity and thermal stability. Moreover the fuel cell performance of PA doped PDC 3 composite membranes is enhanced in comparison with PA doped PMC 6 and PA doped PBI membranes at high temperatures. Dicationic ionic liquid with high number of charge carriers provides well-developed ionic channels which form facile pathways and considerably develop the anhydrous proton conductivity. The highest proton conductivity of 81 mS/cm is achieved for PA doped PDC 3 composite membranes with PBI/IL mole ratio: 4 at 180 °C. A power density of 0.44 W/cm 2 is obtained at 0.5 V and 180 °C for PA doped PDC 3 composite membranes, which proves that these developed composite membranes can be considered as most promising candidates for high temperature fuel cell applications with enhanced proton conductivity.

Synthesis and sintering of UN-UO{sub 2} fuel composites

Energy Technology Data Exchange (ETDEWEB)

Jaques, Brian J., E-mail: BrianJaques@BoiseState.edu [Department of Materials Science and Engineering, Boise State University, 1910 University Dr., Boise, ID 83725 (United States); Center for Advanced Energy Studies, 995 University Blvd., Idaho Falls, ID 83401 (United States); Watkins, Jennifer; Croteau, Joseph R.; Alanko, Gordon A. [Department of Materials Science and Engineering, Boise State University, 1910 University Dr., Boise, ID 83725 (United States); Center for Advanced Energy Studies, 995 University Blvd., Idaho Falls, ID 83401 (United States); Tyburska-Püschel, Beata [Department of Engineering Physics, University of Wisconsin–Madison, 1500 Engineering Dr., Madison, WI 53706 (United States); Meyer, Mitch [Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Xu, Peng; Lahoda, Edward J. [Westinghouse Electric Company LLC, Pittsburgh, PA 15235 (United States); Butt, Darryl P., E-mail: DarrylButt@BoiseState.edu [Department of Materials Science and Engineering, Boise State University, 1910 University Dr., Boise, ID 83725 (United States); Center for Advanced Energy Studies, 995 University Blvd., Idaho Falls, ID 83401 (United States)

2015-11-15

The design and development of an economical, accident tolerant fuel (ATF) for use in the current light water reactor (LWR) fleet is highly desirable for the future of nuclear power. Uranium mononitride has been identified as an alternative fuel with higher uranium density and thermal conductivity when compared to the benchmark, UO{sub 2}, which could also provide significant economic benefits. However, UN by itself reacts with water at reactor operating temperatures. In order to reduce its reactivity, the addition of UO{sub 2} to UN has been suggested. In order to avoid carbon impurities, UN was synthesized from elemental uranium using a hydride-dehydride-nitride thermal synthesis route prior to mixing with up to 10 wt% UO{sub 2} in a planetary ball mill. UN and UN – UO{sub 2} composite pellets were sintered in Ar – (0–1 at%) N{sub 2} to study the effects of nitrogen concentration on the evolved phases and microstructure. UN and UN-UO{sub 2} composite pellets were also sintered in Ar – 100 ppm N{sub 2} to assess the effects of temperature (1700–2000 °C) on the final grain morphology and phase concentration.

Indirect Determination of Chemical Composition and Fuel Characteristics of Solid Waste

DEFF Research Database (Denmark)

Riber, Christian; Christensen, Thomas Højlund

Determination of chemical composition of solid waste can be performed directly or indirectly by analysis of combustion products. The indirect methodology instrumented by a full scale incinerator is the only method that can conclude on elements in trace concentrations. These elements are of great...... interest in evaluating waste management options by for example LCA modeling. A methodology description of indirect determination of chemical composition and fuel properties of waste is provided and validated by examples. Indirect analysis of different waste types shows that the chemical composition...... is significantly dependent on waste type. And the analysis concludes that the transfer of substances in the incinerator is a function of waste chemical content, incinerator technology and waste physical properties. The importance of correct representation of rare items in the waste with high concentrations...

Synthesis of biodiesel fuel from safflower oil using various reaction parameters.

Science.gov (United States)

Meka, Pavan Kumar; Tripathi, Vinay; Singh, R P

2006-01-01

Biodiesel fuel is gaining more and more importance because of the depletion and uncontrollable prices of fossil fuel resources. The use of vegetable oil and their derivatives as alternatives for diesel fuel is the best answer and as old as Diesel Engine. Chemically biodiesel fuel is the mono alkyl esters of fatty acids derived from renewable feed stocks like vegetable oils and animal fats. Safflower oil contains 75-80% of linoleic acid; the presence of this unsaturated fatty acid is useful in alleviating low temperature properties like pour point, cloud point and cold filter plugging point. In this paper we studied the effect of various parameters such as temperature, molar ratio (oil to alcohol), and concentration of catalyst on synthesis of biodiesel fuel from safflower oil. The better suitable conditions of 1:6 molar ratio (oil to alcohol), 60 degrees C temperature and catalyst concentration of 2% (by wt. of oil) were determined. The finally obtained biodiesel fuel was analyzed for fatty acid composition by GLC and some other properties such as flash point, specific gravity and acid value were also determined. From the results it was clear that the produced biodiesel fuel was with in the recommended standards of biodiesel fuel with 96.8% yield.

Fuel characteristics pertinent to the design of aircraft fuel systems

Science.gov (United States)

Barnett, Henry C; Hibbard, R R

1953-01-01

Because of the importance of fuel properties in design of aircraft fuel systems the present report has been prepared to provide information on the characteristics of current jet fuels. In addition to information on fuel properties, discussions are presented on fuel specifications, the variations among fuels supplied under a given specification, fuel composition, and the pertinence of fuel composition and physical properties to fuel system design. In some instances the influence of variables such as pressure and temperature on physical properties is indicated. References are cited to provide fuel system designers with sources of information containing more detail than is practicable in the present report.

Development of Start-up and Shutdown Procedure for the HANARO Fuel Test Loop

International Nuclear Information System (INIS)

Park, S. K.; Sim, B. S.; Chi, D. Y.; Lee, J. M.; Lee, C. Y.; Ahn, S. H.

2009-06-01

A start-up and shutdown procedure for the HANARO fuel test loop has been developed. This is a facility for fuel and material irradiation tests. The facility provides experimental conditions similar to the normal operational pressures and temperatures of commercial PWR and CANDU plants. The normal operation modes of the HANARO fuel test loop are classified into loop shutdown, cold stand-by 1, cold stand-by 2, hot stand-by, and hot operation. The operation modes depend on the fission power of test fuels and the coolant temperature at the inlet of the in-pile test section. The HANARO must maintain a shutdown mode if the HANARO fuel test loop is loop shutdown, cold stand-by 1, cold stand-by 2, or hot stand-by. As the HANARO becomes power operation mode, the operation mode of the HANARO fuel test loop comes to hot operation from hot stand-by. The procedure for the HANARO fuel test loop consists of four main parts such as check of initial conditions, stat-up operation procedure, shutdown operation procedure, and check lists for operations. Several hot test operations ensure that the procedure is appropriate

The evaluation of isotopic composition for TRIGA 14 MW spent fuel

International Nuclear Information System (INIS)

Covaci, St.; Toma, C.; Preda, M.

2008-01-01

In the summer of 1999 year, a first shipment of TRIGA HEU spent fuel to INEEL U.S.A. has taken place. he TRIGA HEU fuel was burned in the TRIGA steady state 14 MW reactor between 1980 and 1996 years. At the moment of prepared documentation for the shipment (July 1999), the evaluation of isotopic composition was calculated with ORIGEN-2 code with an irradiation history adequately prepared. Subsequently (May - June 2000), the evaluation was repeated with SAS2H module of SCALE 4.4a system. In the paper the results and the comparisons of the codes are presented, and the accuracy and convenient application of SCALE 4.4a system are emphasized. (authors)

Cold pressed versus refined winterized corn oils: quality, composition and aroma

International Nuclear Information System (INIS)

Aydeniz Güneşer, B.; Yılmaz, E.; Ok, S.

2017-01-01

The aims of this study were to characterize and compare cold pressed and fully refined winterized corn oils. Free fatty acidity (FFA), peroxide (PV) and p-anisidin (p-AV) values, saponification number, total carotenoid and phenolic contents of cold pressed corn oils were higher than that of the refined winterized corn oils. Linoleic and oleic acids (approximately 53-54% and 30-31%, respectively) were detected as the major fatty acids in both oil samples. Fifteen different sterols with a majority of β-sitosterol, campesterol, and stigmasterol were quantified in both oil samples. Although phenolic compounds were not quantified in the refined winterized oil samples, some flavonoids (hesperidin, rutin) and phenolic acids (gallic, syringic, rosmaniric and trans-ferulic) were detected in the cold pressed oil samples. This study concludes that cold pressed corn oils could be superior in terms of bioactive compounds but still need some quality improvements for sensory attributes. [es

Densification behavior of aluminum alloy powder mixed with zirconia powder inclusion under cold compaction

International Nuclear Information System (INIS)

Ryu, Hyun Seok; Lee, Sung Chul; Kim, Ki Tae

2002-01-01

Densification behavior of composite powders was investigated during cold compaction. Experimental data were obtained for aluminum alloy powder mixed with zirconia powder inclusion under triaxial compression. The cap model with constraint factors was implemented into a finite element program(ABAQUS) to simulate compaction responses of composite powders during cold compaction. Finite element results were compared with experimental data for densification behavior of composite powders under cold isostatic pressing and die compaction. The agreements between experimental data and finite element calculations from the cap model with constraint factors were good

Spent fuel composition database system on WWW. SFCOMPO on WWW Ver.2

Energy Technology Data Exchange (ETDEWEB)

Mochizuki, Hiroki [Japan Research Institute, Ltd., Tokyo (Japan); Suyama, Kenya; Nomura, Yasushi; Okuno, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2001-08-01

'SFCOMPO on WWW Ver.2' is an advanced version of 'SFCOMPO on WWW' ('Spent Fuel Composition Database System on WWW') released in 1997. This new version has a function of database management by an introduced relational database software 'PostgreSQL' and has various searching methods. All of the data required for the calculation of isotopic composition is available from the web site of this system. This report describes the outline of this system and the searching method using Internet. In addition, the isotopic composition data and the reactor data of the 14 LWRs (7 PWR and 7 BWR) registered in this system are described. (author)

Cold Vacuum Drying facility design basis accident analysis documentation

International Nuclear Information System (INIS)

CROWE, R.D.

2000-01-01

This document provides the detailed accident analysis to support HNF-3553, Annex B, Spent Nuclear Fuel Project Final Safety Analysis Report (FSAR), ''Cold Vacuum Drying Facility Final Safety Analysis Report.'' All assumptions, parameters, and models used to provide the analysis of the design basis accidents are documented to support the conclusions in the FSAR. The calculations in this document address the design basis accidents (DBAs) selected for analysis in HNF-3553, ''Spent Nuclear Fuel Project Final Safety Analysis Report'', Annex B, ''Cold Vacuum Drying Facility Final Safety Analysis Report.'' The objective is to determine the quantity of radioactive particulate available for release at any point during processing at the Cold Vacuum Drying Facility (CVDF) and to use that quantity to determine the amount of radioactive material released during the DBAs. The radioactive material released is used to determine dose consequences to receptors at four locations, and the dose consequences are compared with the appropriate evaluation guidelines and release limits to ascertain the need for preventive and mitigative controls

Cold Vacuum Drying facility design basis accident analysis documentation

Energy Technology Data Exchange (ETDEWEB)

CROWE, R.D.

2000-08-08

This document provides the detailed accident analysis to support HNF-3553, Annex B, Spent Nuclear Fuel Project Final Safety Analysis Report (FSAR), ''Cold Vacuum Drying Facility Final Safety Analysis Report.'' All assumptions, parameters, and models used to provide the analysis of the design basis accidents are documented to support the conclusions in the FSAR. The calculations in this document address the design basis accidents (DBAs) selected for analysis in HNF-3553, ''Spent Nuclear Fuel Project Final Safety Analysis Report'', Annex B, ''Cold Vacuum Drying Facility Final Safety Analysis Report.'' The objective is to determine the quantity of radioactive particulate available for release at any point during processing at the Cold Vacuum Drying Facility (CVDF) and to use that quantity to determine the amount of radioactive material released during the DBAs. The radioactive material released is used to determine dose consequences to receptors at four locations, and the dose consequences are compared with the appropriate evaluation guidelines and release limits to ascertain the need for preventive and mitigative controls.

Fabrication of 0.5-inch diameter FBR mixed oxide fuel pellets

International Nuclear Information System (INIS)

Rasmussen, D.E.; Benecke, M.W.; McCord, R.B.

1979-01-01

Large diameter (0.535 inch) mixed oxide fuel pellets for Fast Breeder Reactor application were successfully fabricated by the cold-press-and-sinter technique. Enriched UO 2 , PuO 2 -UO 2 , and PuO 2 -ThO 2 compositions were fabricated into nominally 90% theoretical density pellets for the UO 2 and PuO 2 -UO 2 compositions, and 88% and 93% T.D. for the PuO 2 -ThO 2 compositions. Some processing adjustments were required to achieve satisfactory pellet quality and density. Furnace heating rate was reduced from 200 to 50 0 C/h for the organic binder burnout cycle for the large, 0.535-inch diameter pellets to eliminate pellet cracking during sintering. Additional preslugging steps and die wall lubrication during pressing were used to eliminate pressing cracks in the PuO 2 -ThO 2 pellets

Fuel cycles with high fuel burn-up: analysis of reactivity coefficients

International Nuclear Information System (INIS)

Kryuchkov, E.F.; Shmelev, A.N.; Ternovykh, M.J.; Tikhomirov, G.V.; Jinhong, L.; Saito, M.

2003-01-01

Fuel cycles of light-water reactors (LWR) with high fuel burn-up (above 100 MWd/kg), as a rule, involve large amounts of fissionable materials. It leads to forming the neutron spectrum harder than that in traditional LWR. Change of neutron spectrum and significant amount of non-traditional isotopes (for example, 237 Np, 238 Pu, 231 Pa, 232 U) in such fuel compositions can alter substantially reactivity coefficients as compared with traditional uranium-based fuel. The present work addresses the fuel cycles with high fuel burn-up which are based on Th-Pa-U and U-Np-Pu fuel compositions. Numerical analyses are carried out to determine effective neutron multiplication factor and void reactivity coefficient (VRC) for different values of fuel burn-up and different lattice parameters. The algorithm is proposed for analysis of isotopes contribution to these coefficients. Various ways are considered to upgrade safety of nuclear fuel cycles with high fuel burn-up. So, the results obtained in this study have demonstrated that: -1) Non-traditional fuel compositions developed for achievement of high fuel burn-up in LWR can possess positive values of reactivity coefficients that is unacceptable from the reactor operation safety point of view; -2) The lattice pitch of traditional LWR is not optimal for non-traditional fuel compositions, the increased value of the lattice pitch leads to larger value of initial reactivity margin and provides negative VRC within sufficiently broad range of coolant density; -3) Fuel burn-up has an insignificant effect on VRC dependence on coolant density, so, the measures undertaken to suppress positive VRC of fresh fuel will be effective for partially burnt-up fuel compositions also and; -4) Increase of LWR core height and introduction of additional moderators into the fuel lattice can be used as the ways to reach negative VRC values for full range of possible coolant density variations

Composite cathode based on yttria stabilized bismuth oxide for low-temperature solid oxide fuel cells

International Nuclear Information System (INIS)

Xia Changrong; Zhang Yuelan; Liu Meilin

2003-01-01

Composites consisting of silver and yttria stabilized bismuth oxide (YSB) have been investigated as cathodes for low-temperature honeycomb solid oxide fuel cells with stabilized zirconia as electrolytes. At 600 deg. C, the interfacial polarization resistances of a porous YSB-Ag cathode is about 0.3 Ω cm 2 , more than one order of magnitude smaller than those of other reported cathodes on stabilized zirconia. For example, the interfacial resistances of a traditional YSZ-lanthanum maganites composite cathode is about 11.4 Ω cm 2 at 600 deg. C. Impedance analysis indicated that the performance of an YSB-Ag composite cathode fired at 850 deg. C for 2 h is severely limited by gas transport due to insufficient porosity. The high performance of the YSB-Ag cathodes is very encouraging for developing honeycomb fuel cells to be operated at temperatures below 600 deg. C

Post-irradiation examinations of THERMHET composite fuels for transmutation

Science.gov (United States)

Noirot, J.; Desgranges, L.; Chauvin, N.; Georgenthum, V.

2003-07-01

The thermal behaviour of composite targets dedicated to minor actinide transmutation was studied using THERMHET (thermal behaviour of heterogeneous fuel) irradiation in the SILOE reactor. Three inert matrix fuel designs were tested (macro-mass, jingle and microdispersion) all with a MgAl 2O 4 spinel inert matrix and around 40% weight of UO 2 to simulate minor actinide inclusions. The post-irradiation examinations led to a new interpretation of the temperature measurement by thermocouples located in the central hole of the pellets. A major change in the micro-dispersed structure was detected. The examinations enabled us to understand the behaviour of the spinel during the different stages of irradiation. They revealed an amorphisation at low temperature and then a nano re-crystallisation at high temperature of the spinel in the micro-dispersed case. These results, together with those obtained in the MATINA irradiation of an equivalent structure, show the importance of the irradiation temperature on spinel behaviour.

Post-irradiation examinations of THERMHET composite fuels for transmutation

Energy Technology Data Exchange (ETDEWEB)

Noirot, J. E-mail: jnoirot@cea.fr; Desgranges, L.; Chauvin, N.; Georgenthum, V

2003-07-01

The thermal behaviour of composite targets dedicated to minor actinide transmutation was studied using THERMHET (thermal behaviour of heterogeneous fuel) irradiation in the SILOE reactor. Three inert matrix fuel designs were tested (macro-mass, jingle and microdispersion) all with a MgAl{sub 2}O{sub 4} spinel inert matrix and around 40% weight of UO{sub 2} to simulate minor actinide inclusions. The post-irradiation examinations led to a new interpretation of the temperature measurement by thermocouples located in the central hole of the pellets. A major change in the micro-dispersed structure was detected. The examinations enabled us to understand the behaviour of the spinel during the different stages of irradiation. They revealed an amorphisation at low temperature and then a nano re-crystallisation at high temperature of the spinel in the micro-dispersed case. These results, together with those obtained in the MATINA irradiation of an equivalent structure, show the importance of the irradiation temperature on spinel behaviour.

Post-irradiation examinations of THERMHET composite fuels for transmutation

International Nuclear Information System (INIS)

Noirot, J.; Desgranges, L.; Chauvin, N.; Georgenthum, V.

2003-01-01

The thermal behaviour of composite targets dedicated to minor actinide transmutation was studied using THERMHET (thermal behaviour of heterogeneous fuel) irradiation in the SILOE reactor. Three inert matrix fuel designs were tested (macro-mass, jingle and microdispersion) all with a MgAl 2 O 4 spinel inert matrix and around 40% weight of UO 2 to simulate minor actinide inclusions. The post-irradiation examinations led to a new interpretation of the temperature measurement by thermocouples located in the central hole of the pellets. A major change in the micro-dispersed structure was detected. The examinations enabled us to understand the behaviour of the spinel during the different stages of irradiation. They revealed an amorphisation at low temperature and then a nano re-crystallisation at high temperature of the spinel in the micro-dispersed case. These results, together with those obtained in the MATINA irradiation of an equivalent structure, show the importance of the irradiation temperature on spinel behaviour

A study on the criticality search of transuranium recycling BWR core by adjusting supplied fuel composition in equilibrium state

International Nuclear Information System (INIS)

Seino, Takeshi; Sekimoto, Hiroshi

1997-01-01

There have been some difficulties in carrying out an extensive evaluation of the equilibrium state of Light Water Reactor (LWR) recycling operations keeping their fixed criticality condition using conventional design codes, because of the complexity of their calculational model for practical fuel and core design and because of a large amount of calculation time. This study presents an efficient approach to secure the criticality in an equilibrium cycle by adjusting a supplied fuel composition. The criticality search is performed by the use of fuel importance obtained from the equilibrium adjoint to a continuously fuel supplied core burnup equation. Using this method, some numerical analyses were carried out in order to evaluate the mixed oxide (MOX) fuel composition of equilibrium Boiling Water Reactor (BWR) cores satisfying the criticality requirement. The results showed the comprehensive and quantitative characteristics on the equilibrium cores confining transuranium for different MOX fuel loading fractions and irradiating conditions. (author)

Proton conductive montmorillonite-Nafion composite membranes for direct ethanol fuel cells

Energy Technology Data Exchange (ETDEWEB)

Wu, Xiu-Wen, E-mail: wuxw2008@163.com [School of Science, China University of Geosciences, Beijing 100083 (China); National Laboratory of Mineral Materials, China University of Geosciences, Beijing 100083 (China); Wu, Nan; Shi, Chun-Qing; Zheng, Zhi-Yuan; Qi, Hong-Bin; Wang, Ya-Fang [School of Science, China University of Geosciences, Beijing 100083 (China)

2016-12-01

Highlights: • Composite membranes are prepared with different montmorillonites and nafion solution. • Proton conductivities of the composite membranes are between 36.0 mS/cm and 38.5 mS/cm. • Ethanol permeability is between 0.69 × 10{sup −6} cm{sup 2}/s and 2.67 × 10{sup −6} cm{sup 2}/s. • Water uptake is approximately 24.30 mass%. - Abstract: The preparation of Nafion membranes modified with montmorillonites is less studied, and most relative works mainly applied in direct methanol fuel cells, less in direct ethanol fuel cells. Organic/inorganic composite membranes are prepared with different montmorillonites (Ca-montmorillonite, Na-montmorillonite, K-montmorillonite, Mg-montmorillonite, and H-montmorillonite) and Nafion solution via casting method at 293 K in air, and with balance of their proton conductivity and ethanol permeability. The ethanol permeability and proton conductivity of the membranes are comparatively studied. The montmorillonites can well decrease the ethanol permeability of the membranes via inserted them in the membranes, while less decrease the proton conductivities of the membranes depending on the inserted amount and type of montmorillonites. The proton conductivities of the membranes are between 36.0 mS/cm and 38.5 mS/cm. The ethanol permeability of the membranes is between 0.69 × 10{sup −6} cm{sup 2}/s and 2.67 × 10{sup −6} cm{sup 2}/s.

Fuel Cycle Concept with Advanced METMET and Composite Fuel in LWRs

International Nuclear Information System (INIS)

Savchenko, A.; Skupov, M.; Vatulin, A.; Glushenkov, A.; Kulakov, G.; Lipkina, K.

2014-01-01

The basic factor that limits the serviceability of fuel elements developing in the framework of RERTR Program (transition from HEU to LEU fuel of research reactors) is interaction between U10Mo fuel and aluminium matrix . Interaction results in extra swelling of fuels, disappearance of a heat conducting matrix, a temperature rise in the fuel centre, penetration porosity, etc. Several methods exist to prevent fuel-matrix interaction. In terms of simplifying fuel element fabrication technology and reducing interaction, doping of fuel is the most optimal version

Plant plasma membrane proteomics for improving cold tolerance

Directory of Open Access Journals (Sweden)

Daisuke eTakahashi

2013-04-01

Full Text Available Plants are always exposed to various stresses. We have focused on freezing stress, which causes serious problems for agricultural management. When plants suffer freeze-induced damage, the plasma membrane is thought to be the primary site of injury because of its central role in regulation of various cellular processes. Cold tolerant species, however, adapt to such freezing conditions by modifying cellular components and functions (cold acclimation. One of the most important adaptation mechanisms to freezing is alteration of plasma membrane compositions and functions. Advanced proteomic technologies have succeeded in identification of many candidates that may play roles in adaptation of the plasma membrane to freezing stress. Proteomics results suggest that adaptations of plasma membrane functions to low temperature are associated with alterations of protein compositions during cold acclimation. Some of proteins identified by proteomic approaches have been verified their functional roles in freezing tolerance mechanisms further. Thus, accumulation of proteomic results in the plasma membrane is of importance for application to molecular breeding efforts to increase cold tolerance in crops.

Optimized chemical composition, working and heat treatment condition for resistance to irradiation assisted stress corrosion cracking of cold worked 316 and high-chromium austenitic stainless steel

International Nuclear Information System (INIS)

Yonezawa, Toshio; Iwamura, Toshihiko; Fujimoto, Koji; Ajiki, Kazuhide

2000-01-01

The authors have reported that the primary water stress corrosion cracking (PWSCC) in baffle former bolts made of austenitic stainless steels for PWR after long-term operation is caused by irradiation-induced grain boundary segregation. The resistance to PWSCC of simulated austenitic stainless steels whose chemical compositions are simulated to the grain boundary chemical composition of 316 stainless steel after irradiation increased with decrease of the silicon content, increases of the chromium content, and precipitation of M 23 C 6 carbides at the grain boundaries. In order to develop resistance to irradiation assisted stress corrosion cracking in austenitic stainless steels, optimized chemical compositions and heat treatment conditions for 316CW and high-chromium austenitic stainless steels for PWR baffle former bolts were investigated. For 316CW stainless steel, ultra-low-impurities and high-chromium content are beneficial. About 20% cold working before aging and after solution treatment has also been recommended to recover sensitization and make M 23 C 6 carbides coherent with the matrix at the grain boundaries. Heating at 700 to 725degC for 20 to 50 h was selected as a suitable aging procedure. Cold working of 5 to 10% after aging produced the required mechanical properties. The optimized composition of the high-chromium austenitic stainless steel contents 30% chromium, 30% nickel, and ultra-low impurity levels. This composition also reduces the difference between its thermal expansion coefficient and that of 304 stainless steel for baffle plates. Aging at 700 to 725degC for longer than 40 h and cold working of 10 to 15% after aging were selected to meet mechanical property specifications. (author)

Caramel fuel for research reactors

International Nuclear Information System (INIS)

Bussy, P.

1979-11-01

This fuel for research reactors is made of UO 2 pellets in a zircaloy cladding to replace 93% enriched uranium. It is a cold fuel, non contaminating and non proliferating, enrichment is only 7 to 8%. Irradiation tests were performed until burn-up of 50000 MWD/t [fr

Safety analysis report for the Cold Vacuum Drying Facility, phase 1, supporting civil/structural construction

International Nuclear Information System (INIS)

Pili-Vincens, C.

1997-01-01

The US Department of Energy established the K Basins Spent Nuclear Fuel Project to address safety and environmental concerns associated with deteriorating spent nuclear fuel presently stored under water in the Hanford Site's K Basins, which are located near the Columbia River. Recommendations for a series of aggressive projects to construct and operate systems and facilities to manage the safe removal of K Basins fuel were made in WHC-EP-0830, Hanford Spent Nuclear Fuel Recommended Path Forward,' and its subsequent update, WHC-SD-SNF-SP-005, Hanford Spent Nuclear Fuel Project Integrated Process Strategy for K Basins Fuel. The integrated process strategy recommendations include the following process steps: fuel preparation activities at the K Basins, including removing the fuel elements from their K Basin canisters, separating fuel particulate from fuel elements and fuel fragments greater than 0.6 cm (0.25 in.) in any dimension, removing excess sludge from the fuel and fuel fragments by means of flushing, as necessary, and packaging the fuel into multicanister overpacks; removal of free water by draining and vacuum drying at the Cold Vacuum Drying Facility (CVDF), a new facility in the 100 K Area of the Hanford Site. This report is contains the safety analysis for the Cold Vacuum Drying Facility, Phase 1

Nafion®/ODF-silica composite membranes for medium temperature proton exchange membrane fuel cells

KAUST Repository

Treekamol, Yaowapa

2014-01-01

A series of composite membranes were prepared by dispersing fluorinated polyoxadiazole oligomer (ODF)-functionalized silica nanoparticles in a Nafion matrix. Both melt-extrusion and solvent casting processes were explored. Ion exchange capacity, conductivity, water uptake and dimensional stability, thermal stability and morphology were characterized. The inclusion of functionalized nanoparticles proved advantageous, mainly due to a physical crosslinking effect and better water retention, with functionalized nanoparticles performing better than the pristine silica particles. For the same filler loading, better nanoparticle dispersion was achieved for solvent-cast membranes, resulting in higher proton conductivity. Filler agglomeration, however,was more severe for solvent-castmembranes at loadings beyond 5wt.%. The composite membranes showed excellent thermal stability, allowing for operation in medium temperature PEM fuel cells. Fuel cell performance of the compositemembranesdecreaseswithdecreasing relativehumidity, but goodperformance values are still obtained at 34% RHand 90 °C,with the best results obtained for solvent castmembranes loaded with 10 wt.% ODF-functionalized silica. Hydrogen crossover of the composite membranes is higher than that forpureNafion membranes,possiblydue toporosityresulting fromsuboptimalparticle- matrixcompatibility. © 2013 Crown Copyright and Elsevier BV. All rights reserved.

Determination of optimal wet ethanol composition as a fuel in spark ignition engine

International Nuclear Information System (INIS)

Fagundez, J.L.S.; Sari, R.L.; Mayer, F.D.; Martins, M.E.S.; Salau, N.P.G.

2017-01-01

Highlights: • Batch distillation to produce HEF and fuel blends of wet ethanol. • Conversion efficiency of a SI engine operating with HEF and wet ethanol. • NEF as a new metric to calculate the energy efficiency of HEF and wet ethanol. • Optimal wet ethanol composition as a fuel in SI engine based on NEF. - Abstract: Studies are unanimous that the greatest fraction of the energy necessary to produce hydrous ethanol fuel (HEF), i.e. above 95%v/v of ethanol in water, is spent on water removal (distillation). Previous works have assessed the energy efficiency of HEF; but few, if any, have done the same for wet ethanol fuel (sub-azeotropic hydrous ethanol). Hence, a new metric called net energy factor (NEF) is proposed to calculate the energy efficiency of wet ethanol and HEF. NEF calculates the ratio of Lower Heating Value (LHV) derived from ethanol fuel, total energy out, to energy used to obtain ethanol fuel as distillate, total energy in. Distillation tests were performed batchwise to obtain as distillate HEF and four different fuel blends of wet ethanol with a range from 60%v/v to 90%v/v of ethanol and the amount of energy spent to distillate each ethanol fuel calculated. The efficiency parameters of a SI engine operating with the produced ethanol fuels was tested to calculate their respective conversion efficiency. The results of net energy factors show a clear advantage of wet ethanol fuels over HEF; the optimal efficiency was wet ethanol fuel with 70%v/v of ethanol.

Influence of fuel composition on the non-oxidizing heating of steel in a waste gas atmosphere

Energy Technology Data Exchange (ETDEWEB)

Minkler, W [LOI Industrieofenanlagen G.m.b.H., Essen (Germany, F.R.)

1979-04-01

On the basis of a number of graphs and data on theoretical combustion temperatures and the difference between the heating value of the fuel and the waste gas in respect of 1 m/sup 3/ of waste gas, the author demonstrates the influence of fuel composition on the non-oxidizing heating of steel in a waste gas atmosphere derived from five different fuels. A rotary-hearth furnace is described for the non-oxidizing heating of pressings from plain carbon and alloy steel.

Microstructural characterization of composite cobaltite and lanthanum-based ceria for use as fuel cell cathodes

International Nuclear Information System (INIS)

Rodrigues, E.R.T.; Nascimento, R.M.; Miranda, A.C. de; Lima, A.M. de; Macedo, D.A.

2016-01-01

Fuel cells are devices that convert chemical energy into electricity via redox reactions. In this work, the lanthanum cobaltite doped with strontium and iron (La_0_,_6Sr_0_,_4Co_0_,_2Fe_0_,_8O_3 - LSCF) a traditional cathodes material of the fuel cell was mixed with an electrolyte material (composite) to the base ceria doped with gadolinia and a eutectic mixture of lithium carbonates and sodium (CGO-NLC). The powders of LSCF and CGO-NLC were obtained by the citrate method and mixed to obtain a composite cathode. Samples obtained by uniaxial pressure between 5 and 10 MPa were sintered at 1100°C and investigated by X-ray diffraction, scanning electron microscopy and micro hardness test. A symmetric cell cathode / electrolyte / cathode, obtained by co-pressing and co-sintering was investigated by electron microscopy. The results indicated that the composite is chemically stable up to the sintering temperature used. The hardness ranged between 51 and 227 HV. (author)

Physicochemical effects of varying fuel composition on knock characteristics of natural gas mixtures

NARCIS (Netherlands)

Gersen, Sander; van Essen, Martijn; van Dijk, Gerco; Levinsky, Howard

2014-01-01

The physicochemical origins of how changes in fuel composition affect autoignition of the end gas, leading to engine knock, are analyzed for a natural gas engine. Experiments in a lean-burn, high-speed medium-BMEP gas engine are performed using a reference natural gas with systematically varied

Change of Composition in Metallic Fuel Slug of U-Zr Alloy from High-Temperature Annealing

Energy Technology Data Exchange (ETDEWEB)

Youn, Young Sang; Lee, Jeong Mook; Kim, Jong Yun; Kim, Jong Hwan; Song, Hoon [KAERI, Daejeon (Korea, Republic of)

2016-09-15

The U–Zr alloy is a candidate for fuel to be used as metallic fuel in sodium-cooled fast reactors (SFRs). Its chemical composition before and after annealing at the operational temperature of SFRs (610 .deg. C) was investigated using X-ray photoelectron spectroscopy, Raman spectroscopy, and X-ray diffraction. The original alloy surface contained uranium oxides with the U(IV) and U(VI) oxidation states, Zr{sub 2}O{sub 3}, and a low amount of uranium metal. After annealing at 610 .deg. C, the alloy was composed of uranium metal, uranium carbide, uranium oxide with the U(V) valence state, zirconium metal, and amorphous carbon. Meanwhile, X-ray diffraction data indicate that the bulk composition of the alloy remained unchanged.

Change of Composition in Metallic Fuel Slug of U-Zr Alloy from High-Temperature Annealing

International Nuclear Information System (INIS)

Youn, Young Sang; Lee, Jeong Mook; Kim, Jong Yun; Kim, Jong Hwan; Song, Hoon

2016-01-01

The U–Zr alloy is a candidate for fuel to be used as metallic fuel in sodium-cooled fast reactors (SFRs). Its chemical composition before and after annealing at the operational temperature of SFRs (610 .deg. C) was investigated using X-ray photoelectron spectroscopy, Raman spectroscopy, and X-ray diffraction. The original alloy surface contained uranium oxides with the U(IV) and U(VI) oxidation states, Zr 2 O 3 , and a low amount of uranium metal. After annealing at 610 .deg. C, the alloy was composed of uranium metal, uranium carbide, uranium oxide with the U(V) valence state, zirconium metal, and amorphous carbon. Meanwhile, X-ray diffraction data indicate that the bulk composition of the alloy remained unchanged

Fuel cycles with high fuel burn-up: analysis of reactivity coefficients

Energy Technology Data Exchange (ETDEWEB)

Kryuchkov, E.F.; Shmelev, A.N.; Ternovykh, M.J.; Tikhomirov, G.V.; Jinhong, L. [Moscow Engineering Physics Institute (State University) (Russian Federation); Saito, M. [Tokyo Institute of Technology (Japan)

2003-07-01

Fuel cycles of light-water reactors (LWR) with high fuel burn-up (above 100 MWd/kg), as a rule, involve large amounts of fissionable materials. It leads to forming the neutron spectrum harder than that in traditional LWR. Change of neutron spectrum and significant amount of non-traditional isotopes (for example, {sup 237}Np, {sup 238}Pu, {sup 231}Pa, {sup 232}U) in such fuel compositions can alter substantially reactivity coefficients as compared with traditional uranium-based fuel. The present work addresses the fuel cycles with high fuel burn-up which are based on Th-Pa-U and U-Np-Pu fuel compositions. Numerical analyses are carried out to determine effective neutron multiplication factor and void reactivity coefficient (VRC) for different values of fuel burn-up and different lattice parameters. The algorithm is proposed for analysis of isotopes contribution to these coefficients. Various ways are considered to upgrade safety of nuclear fuel cycles with high fuel burn-up. So, the results obtained in this study have demonstrated that: -1) Non-traditional fuel compositions developed for achievement of high fuel burn-up in LWR can possess positive values of reactivity coefficients that is unacceptable from the reactor operation safety point of view; -2) The lattice pitch of traditional LWR is not optimal for non-traditional fuel compositions, the increased value of the lattice pitch leads to larger value of initial reactivity margin and provides negative VRC within sufficiently broad range of coolant density; -3) Fuel burn-up has an insignificant effect on VRC dependence on coolant density, so, the measures undertaken to suppress positive VRC of fresh fuel will be effective for partially burnt-up fuel compositions also and; -4) Increase of LWR core height and introduction of additional moderators into the fuel lattice can be used as the ways to reach negative VRC values for full range of possible coolant density variations.

Cold Vacuum Drying (CVD) Facility Technical Safety Requirements

International Nuclear Information System (INIS)

KRAHN, D.E.

2000-01-01

The Technical Safety Requirements (TSRs) for the Cold Vacuum Drying Facility define acceptable conditions, safe boundaries, bases thereof, and management or administrative controls required to ensure safe operation during receipt of multi-canister overpacks (MCOs) containing spent nuclear fuel. removal of free water from the MCOs using the cold vacuum drying process, and inerting and testing of the MCOs before transport to the Canister Storage Building. Controls required for public safety, significant defense in depth, significant worker safety, and for maintaining radiological and toxicological consequences below risk evaluation guidelines are included

Gas composition modeling in a reformed Methanol Fuel Cell system using adaptive Neuro-Fuzzy Inference Systems

DEFF Research Database (Denmark)

Justesen, Kristian Kjær; Andreasen, Søren Juhl; Shaker, Hamid Reza

2013-01-01

This work presents a method for modeling the gas composition in a Reformed Methanol Fuel Cell system. The method is based on Adaptive Neuro-Fuzzy-Inference-Systems which are trained on experimental data. The developed models are of the H2, CO2, CO and CH3OH mass flows of the reformed gas. The ANFIS......, or fuel cell diagnostics systems....

Impact of cold temperature on Euro 6 passenger car emissions.

Science.gov (United States)

Suarez-Bertoa, Ricardo; Astorga, Covadonga

2018-03-01

Hydrocarbons, CO, NOx, NH 3 , N 2 O, CO 2 and particulate matter emissions affect air quality, global warming and human health. Transport sector is an important source of these pollutants and high pollution episodes are often experienced during the cold season. However, EU vehicle emissions regulation at cold ambient temperature only addresses hydrocarbons and CO vehicular emissions. For that reason, we have studied the impact that cold ambient temperatures have on Euro 6 diesel and spark ignition (including: gasoline, ethanol flex-fuel and hybrid vehicles) vehicle emissions using the World-harmonized Light-duty Test Cycle (WLTC) at -7 °C and 23 °C. Results indicate that when facing the WLTC at 23 °C the tested vehicles present emissions below the values set for type approval of Euro 6 vehicles (still using NEDC), with the exception of NOx emissions from diesel vehicles that were 2.3-6 times higher than Euro 6 standards. However, emissions disproportionally increased when vehicles were tested at cold ambient temperature (-7 °C). High solid particle number (SPN) emissions (>1 × 10 11 # km -1 ) were measured from gasoline direct injection (GDI) vehicles and gasoline port fuel injection vehicles. However, only diesel and GDI SPN emissions are currently regulated. Results show the need for a new, technology independent, procedure that enables the authorities to assess pollutant emissions from vehicles at cold ambient temperatures. Harmful pollutant emissions from spark ignition and diesel vehicles are strongly and negatively affected by cold ambient temperatures. Only hydrocarbon, CO emissions are currently regulated at cold temperature. Therefore, it is of great importance to revise current EU winter vehicle emissions regulation. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Durable fuel electrode

DEFF Research Database (Denmark)

2017-01-01

the composite. The invention also relates to the use of the composite as a fuel electrode, solid oxide fuel cell, and/or solid oxide electrolyser. The invention discloses a composite for an electrode, comprising a three-dimensional network of dispersed metal particles, stabilised zirconia particles and pores...

Steel weldability. Underbead cold cracking

International Nuclear Information System (INIS)

Marquet, F.; Defourny, J.; Bragard, A.

1977-01-01

The problem of underbead cold cracking has been studied by the implant technique. This approach allows to take into account in a quantitative manner the different factors acting on the cold cracking phenomenon: structure under the weld bead, level of restraint, hydrogen content in the molten metal. The influence of the metallurgical factors depending from the chemical composition of the steel has been examined. It appeared that carbon equivalent is an important factor to explain cold cracking sensitivity but that it is not sufficient to characterize the steel. The results have shown that vanadium may have a deleterious effect on the resistance to cold cracking when the hydrogen content is high and that small silicon additions are beneficient. The influence of the diffusible hydrogen content has been checked and the important action of pre- and postheating has been shown. These treatments allow the hydrogen to escape from the weld before the metal has been damaged. Some inclusions (sulphides) may also decrease the influence of hydrogen. A method based on the implant tests has been proposed which allows to choose and to control safe welding conditions regarding cold cracking

Influence of dispersing additives and blend composition on stability of marine high-viscosity fuels

Directory of Open Access Journals (Sweden)

Т. Н. Митусова

2017-12-01

Full Text Available The article offers a definition of the stability of marine high-viscosity fuel from the point of view of the colloid-chemical concept of oil dispersed systems. The necessity and importance of the inclusion in the current regulatory requirements of this quality parameter of high-viscosity marine fuel is indicated. The objects of the research are high-viscosity marine fuels, the basic components of which are heavy oil residues: fuel oil that is the atmospheric residue of oil refining and viscosity breaking residue that is the product of light thermal cracking of fuel oil. As a thinning agent or distillate component, a light gas oil was taken from the catalytic cracking unit. The stability of the obtained samples was determined through the xylene equivalent index, which characterizes the stability of marine high-viscosity fuel to lamination during storage, transportation and operation processes. To improve performance, the resulting base compositions of high-viscosity marine fuels were modified by introducing small concentrations (0.05 % by weight of stabilizing additives based on oxyethylated amines of domestic origin and alkyl naphthalenes of foreign origin.

Estimation of PWR spent fuel composition using SCALE and SWAT code systems

Energy Technology Data Exchange (ETDEWEB)

Shin, Hee Sung [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Kenya, Suyama; Hiroshi, Okuno [Japan Atomic Energy Research Institute, Tokyo (Japan)

2001-05-01

The isotopic composition calculations were performed for 26 spent fuel samples from Obrigheim PWR reactor and 55 spent fuel samples from 7 PWR reactors using SCALE4.4 SAS2H with 27, 44 and 238 group cross-section libraries and SWAT with 107 group cross-section library. For convenience, the ratio of the measured to calculated value was used as a parameter. The four kinds of the calculation results were compared with the measured data. For many important nuclides for burnup credit criticality safety evaluation, the four methods applied in this study showed good coincidence with measurements in general. More precise observations showed the following results. Less unity ratios were found for Pu-239 and -241 for selected 16 samples out of the 26 samples from Obrigheim reactor. Larger than unity ratios were found for Am-241 for both the 16 and 55 samples. Larger than unity ratios were found for Sm-149 for the 55 samples. In the case of 26 sample SWAT was generally accompanied by larger ratios than those of SAS2H with some exceptions. Based on the measured-to-calculated ratios for 71 samples of a combined set in which 16 selected samples and 55 samples were included, the correction factors that should be multiplied to the calculated isotopic compositions were generated for a conservative estimate of the neutron multiplication factor of a system containing PWR spent fuel, taking burnup credit into account.

Effect of fission yield libraries on the irradiated fuel composition in Monte Carlo depletion calculations

International Nuclear Information System (INIS)

Mitenkova, E.; Novikov, N.

2014-01-01

Improving the prediction of radiation parameters and reliability of fuel behaviour under different irradiation modes is particularly relevant for new fuel compositions, including recycled nuclear fuel. For fast reactors there is a strong dependence of nuclide accumulations on the nuclear data libraries. The effect of fission yield libraries on irradiated fuel is studied in MONTEBURNS-MCNP5-ORIGEN2 calculations of sodium fast reactors. Fission yield libraries are generated for sodium fast reactors with MOX fuel, using ENDF/B-VII.0, JEFF3.1, original library FY-Koldobsky, and GEFY 3.3 as sources. The transport libraries are generated from ENDF/B-VII.0 and JEFF-3.1. Analysis of irradiated MOX fuel using different fission yield libraries demonstrates the considerable spread in concentrations of fission products. The discrepancies in concentrations of inert gases being ∼25%, up to 5 times for stable and long-life nuclides, and up to 10 orders of magnitude for short-lived nuclides. (authors)

Hesitant birth of cold fusion

International Nuclear Information System (INIS)

Bockris, J.O.

1992-01-01

John O'M. Bockris, a distinguished chemistry professor at Texas A ampersand M University, finds the reaction to the announcement of the discovery of cold fusion curious. Two years earlier, he notes, there had been a comparable announcement concerning the discovery of high-temperature superconductivity; it received favorable press coverage for months. The cold-fusion announcement, on the other hand, was met with dour skepticism. When other researchers failed in efforts to duplicate the findings of Martin Fleischmann and B. Stanley Pons, Bockris says, the two scientists were held up to ridicule. Bockris says he found a deep emotional opposition to cold fusion, even within his own department and university. This opposition is fueled in large part, he believes, by big science and the hot fusion lobby. A key indicator of cold fusion is the presence of tritium, Brockis claims. At Texas A ampersand M, large amounts of tritium have been found in some experiments; this also has occurred in experiments at more than 40 laboratories in nine countries, he says. Excess heat production is more difficult to attain, he acknowledges. The cold-fusion controversy has uncovered some unflattering characteristics of the scientific community, Bockris says. Among them are: scientists are no less driven by emotion that business people or politicians; research funding decisions serve to perpetuate the goals of politically powerful interest groups; and ideas have great inertia once planted in a scientist's mind

A 1.5--4 Kelvin detachable cold-sample transfer system: Application to inertially confined fusion with spin-polarized hydrogens fuels

International Nuclear Information System (INIS)

Alexander, N.; Barden, J.; Fan, Q.; Honig, A.

1990-01-01

A compact cold-transfer apparatus for engaging and retrieving samples at liquid helium temperatures (1.5--4K), maintaining the samples at such temperatures for periods of hours, and subsequently inserting them in diverse apparatuses followed by disengagement, is described. The properties of several thermal radiation-insulating shrouds, necessary for very low sample temperatures, are presented. The immediate intended application is transportable target-shells containing highly spin-polarized deuterons in solid HD or D 2 for inertially confined fusion (ICF) experiments. The system is also valuable for unpolarized high-density fusion fuels, as well as for other applications which are discussed. 9 refs., 6 figs

Ultra-clean Fischer-Tropsch (F-T) Fuels Production and Demonstration Project

Energy Technology Data Exchange (ETDEWEB)

Stephen P. Bergin

2006-06-30

The objective of the DOE-NETL Fischer-Tropsch (F-T) Production and Demonstration Program was to produce and evaluate F-T fuel derived from domestic natural gas. The project had two primary phases: (1) fuel production of ultra-clean diesel transportation fuels from domestic fossil resources; and (2) demonstration and performance testing of these fuels in engines. The project also included a well-to-wheels economic analysis and a feasibility study of small-footprint F-T plants (SFPs) for remote locations such as rural Alaska. During the fuel production phase, ICRC partnered and cost-shared with Syntroleum Corporation to complete the mechanical design, construction, and operation of a modular SFP that converts natural gas, via F-T and hydro-processing reactions, into hydrogensaturated diesel fuel. Construction of the Tulsa, Oklahoma plant started in August 2002 and culminated in the production of over 100,000 gallons of F-T diesel fuel (S-2) through 2004, specifically for this project. That fuel formed the basis of extensive demonstrations and evaluations that followed. The ultra-clean F-T fuels produced had virtually no sulfur (less than 1 ppm) and were of the highest quality in terms of ignition quality, saturation content, backend volatility, etc. Lubricity concerns were investigated to verify that commercially available lubricity additive treatment would be adequate to protect fuel injection system components. In the fuel demonstration and testing phase, two separate bus fleets were utilized. The Washington DC Metropolitan Area Transit Authority (WMATA) and Denali National Park bus fleets were used because they represented nearly opposite ends of several spectra, including: climate, topography, engine load factor, mean distance between stops, and composition of normally used conventional diesel fuel. Fuel evaluations in addition to bus fleet demonstrations included: bus fleet emission measurements; F-T fuel cold weather performance; controlled engine dynamometer

Report of generation of the nuclear bank Presto-Cold (T=293 K) for the SVEA-96 fuel with the FMS codes

International Nuclear Information System (INIS)

Alonso V, G.

1992-03-01

In this work it is described in a general way the form in that was generated the Presto Cold database (TF=TM=293 K) of the one SVEA-96 fuel for Laguna Verde. The formation of the bank it was carried out with the ECLIPSE 86-2D, RECORD 89-1A and POLGEN 88-1B of the FMS package installed in the VAX system of the offices of the National Commission of Nuclear Safety and Safeguards in Mexico D.F. The formed bank is denominated L1PG9109. All this was carried out following the 6F3/I/CN029/90/P1 procedure. The generated database contains information of the 10 nuclear parameters required in PRESTO without and with the effect of the control bar for the different arrangements of fuel bars present in the one assemble. All this included in what is known as SUPER option of the bank for PRESTO. (Author)

IFR fuel cycle demonstration in the EBR-II Fuel Cycle Facility

International Nuclear Information System (INIS)

Lineberry, M.J.; Phipps, R.D.; Rigg, R.H.; Benedict, R.W.; Carnes, M.D.; Herceg, J.E.; Holtz, R.E.

1991-01-01

The next major milestone of the IFR (Integral Fast Reactor) program is engineering-scale demonstration of the pyroprocess fuel cycle. The EBR-II Fuel Cycle Facility has just entered a startup phase which includes completion of facility modifications, and installation and cold checkout of process equipment. This paper reviews the design and construction of the facility, the design and fabrication of the process equipment, and the schedule and initial plan for its operation. (author)

IFR fuel cycle demonstration in the EBR-II Fuel Cycle Facility

International Nuclear Information System (INIS)

Lineberry, M.J.; Phipps, R.D.; Rigg, R.H.; Benedict, R.W.; Carnes, M.D.; Herceg, J.E.; Holtz, R.E.

1991-01-01

The next major milestone of the IFR program is engineering-scale demonstration of the pyroprocess fuel cycle. The EBR-II Fuel Cycle Facility has just entered a startup phase which includes completion of facility modifications, and installation and cold checkout of process equipment. This paper reviews the design and construction of the facility, the design and fabrication of the process equipment, and the schedule and initial plan for its operation. 5 refs., 4 figs

Lube-oil dilution of gasoline direct-injection engines with ethanol fuels; Schmieroelverduennung von direkteinspritzenden Ottomotoren unter Kaltstartrandbedingungen

Energy Technology Data Exchange (ETDEWEB)

Kuepper, Carsten; Pischinger, Stefan [RWTH Aachen Univ. (Germany). Lehrstuhl fuer Verbrennungskraftmaschinen (VKA); Artmann, Chrsitina; Rabl, Hans-Peter [Hochschule Regensburg (Germany). Labor fuer Verbrennungsmotoren und Abgasnachbehandlung

2013-09-15

Ethanol fuel mixtures account for the majority of biofuels used worldwide. However, their properties make these fuels more difficult to use in cold conditions and especially when starting a cold engine. As part of the FVV research project 'Lubricant Dilution with Ethanol Fuels under Cold Start Conditions', the Institute for Combustion Engines (VKA) at RWTH Aachen University and the Combustion Engines and Emission Control Laboratory at Regensburg University of Applied Sciences have investigated the influence of the ethanol content in fuels on the dilution of the lubricating oil in modern direct-injection gasoline engines. (orig.)

Final Scientific Report, New Proton Conductive Composite Materials for PEM Fuel Cells

Energy Technology Data Exchange (ETDEWEB)

Lvov, Serguei

2010-11-08

This project covered one of the main challenges in present-day PEM fuel cell technology: to design a membrane capable of maintaining high conductivity and mechanical integrity when temperature is elevated and water vapor pressure is severely reduced. The DOE conductivity milestone of 0.1 S cm-1 at 120 degrees C and 50 % relative humidity (RH) for designed membranes addressed the target for the project. Our approach presumed to develop a composite membrane with hydrophilic proton-conductive inorganic material and the proton conductive polymeric matrix that is able to “bridge” the conduction paths in the membrane. The unique aspect of our approach was the use of highly functionalized inorganic additives to benefit from their water retention properties and high conductivity as well. A promising result turns out that highly hydrophilic phosphorsilicate gels added in Nafion matrix improved PEM fuel cell performance by over 50% compared with bare Nafion membrane at 120 degrees C and 50 % RH. This achievement realizes that the fuel cell operating pressure can be kept low, which would make the PEM fuel cell much more cost efficient and adaptable to practical operating conditions and facilitate its faster commercialization particularly in automotive and stationary applications.

Cold crucible induction melter studies for making glass ceramic waste forms: A feasibility assessment

International Nuclear Information System (INIS)

Crum, Jarrod; Maio, Vince; McCloy, John; Scott, Clark; Riley, Brian; Benefiel, Brad; Vienna, John; Archibald, Kip; Rodriguez, Carmen; Rutledge, Veronica; Zhu, Zihua; Ryan, Joe; Olszta, Matthew

2014-01-01

Glass ceramics are being developed to immobilize fission products, separated from used nuclear fuel by aqueous reprocessing, into a stable waste form suitable for disposal in a geological repository. This work documents the glass ceramic formulation at bench scale and for a scaled melter test performed in a pilot-scale (∼1/4 scale) cold crucible induction melter (CCIM). Melt viscosity, electrical conductivity, and crystallization behavior upon cooling were measured on a small set of compositions to select a formulation for melter testing. Property measurements also identified a temperature range for melter operation and cooling profiles necessary to crystallize the targeted phases in the waste form. Bench scale and melter run results successfully demonstrate the processability of the glass ceramic using the CCIM melter technology

Smart FRP Composite Sandwich Bridge Decks in Cold Regions

Science.gov (United States)

2011-07-01

In this study, new and integrated Smart honeycomb Fiber-Reinforced Polymer (S-FRP) : sandwich materials for various transportation construction applications, with particular emphasis : on highway bridge decks in cold regions, were developed and teste...

Radionuclide compositions of spent fuel and high level waste from commercial nuclear reactors

International Nuclear Information System (INIS)

Goodill, D.R.; Tymons, B.J.

1984-10-01

This report provides information on radionuclide compositions of spent fuel and high level waste produced during reprocessing. The reactor types considered are Magnox, AGR, PWR and CFR. The activities of the radionuclides are calculated using the FISPIN code. The results are presented in a form suitable for radioactive waste management calculations. (author)

Introducing the book 'Cold fusion and the future'

International Nuclear Information System (INIS)

Rothwell, Jed

2006-01-01

Cold fusion will be the ideal source of energy, provided its introduction can be handled properly. A few cells have shown power density and temperatures suitable for real-world applications. Once these cells can be replicated on demand, commercial development will be straightforward. Manufacturing should not be too demanding, so thousands of companies will compete, and costs will fall quickly. The transition from fossil fuel to cold fusion will be rapid. Many extraordinary new applications will become possible, and seemingly intractable problems such as global warming may be fixed. Some examples will be presented. Public support is essential to funding research, and commercialization. 'Cold Fusion and the Future' is the title of a new book by this author. This paper discusses a few of the topics in the book

Effect of Fuel Composition on Particulate Matter Emissions from a Gasoline Direct Injection Engine

Science.gov (United States)

Smallwood, Bryden Alexander

The effects of fuel composition on reducing PM emissions were investigated using a Ford Focus wall-guided gasoline direct injection engine (GDI). Initial results with a 65% isooctane and 35% toluene blend showed significant reductions in PM emissions. Further experiments determined that this decrease was due to a lack of light-end components in that fuel blend. Tests with pentane content lower than 15% were found to have PN concentrations 96% lower than tests with 20% pentane content. This indicates that there is a shift in mode of soot production. Pentane significantly increases the vapour pressure of the fuel blend, potentially resulting in surface boiling, less homogeneous mixtures, or decreased fuel rebound from the piston. PM mass measurements and PN Index values both showed strong correlations with the PN concentration emissions. In the gaseous exhaust, THC, pentane, and 1,3 butadiene showed strong correlations with the PM emissions.

The pinch of cold ions from recycling in the tokamak edge pedestal

International Nuclear Information System (INIS)

Wan Weigang; Parker, Scott E.; Chen Yang; Park, Gun-Young; Chang, Choong-Seock; Stotler, Daren

2011-01-01

We apply the ''natural fueling mechanism'' [W. Wan, S. E. Parker, Y. Chen, and F. W. Perkins, Phys. Plasmas 17, 040701 (2010)] to the edge pedestal. The natural fueling mechanism is where cold ions naturally pinch radially inward for a heat-flux dominated plasma. It is shown from neoclassical-neutral transport coupled simulations that the recycling neutrals and the associated source ions are colder than the main ions in the edge pedestal. These recycling source ions will pinch radially inward due to microturbulence. Gyrokinetic turbulence simulations indicate that near the top of the pedestal, the pinch velocity of the recycling source ions is much higher than the main ion outgoing flow velocity. The turbulent pinch of the recycling source ions may play a role in the edge pedestal transport and dynamics. The cold ion temperature significantly enhances the pinch velocity of the recycling source ions near to the pedestal top. Neoclassical calculations show a cold ion pinch in the pedestal as well.

Making mushy magma chambers in the lower continental crust: Cold storage and compositional bimodality

Science.gov (United States)

Jackson, Matthew; Blundy, Jon; Sparks, Steve

2017-04-01

Increasing geological and geophysical evidence suggests that crustal magma reservoirs are normally low melt fraction 'mushes' rather than high melt fraction 'magma chambers'. Yet high melt fractions must form within these mush reservoirs to explain the observed flow and eruption of low crystallinity magmas. In many models, crystallinity is linked directly to temperature, with higher temperature corresponding to lower crystallinity (higher melt fraction). However, increasing temperature yields less evolved (silicic) melt composition for a given starting material. If mobile, low crystallinity magmas require high temperature, it is difficult to explain how they can have evolved composition. Here we use numerical modelling to show that reactive melt flow in a porous and permeable mush reservoir formed by the intrusion of numerous basaltic sills into the lower continental crust produces magma in high melt fraction (> 0.5) layers akin to conventional magma chambers. These magma-chamber-like layers contain evolved (silicic) melt compositions and form at low (close to solidus) temperatures near the top of the mush reservoir. Evolved magma is therefore kept in 'cold storage' at low temperature, but also at low crystallinity so the magma is mobile and can leave the mush reservoir. Buoyancy-driven reactive flow and accumulation of melt in the mush reservoir controls the temperature and composition of magma that can leave the reservoir. The modelling also shows that processes in lower crustal mush reservoirs produce mobile magmas that contain melt of either silicic or mafic composition. Intermediate melt compositions are present but are not within mobile magmas. Silicic melt compositions are found at high melt fraction within the magma-chamber like layers near the top of the mush reservoir. Mafic melt compositions are found at high melt fraction within the cooling sills. Melt elsewhere in the reservoir has intermediate composition, but remains trapped in the reservoir because

Nuclear fuel assembly

International Nuclear Information System (INIS)

Hirano, Yasushi; Hirukawa, Koji; Sakurada, Koichi.

1994-01-01

A bundle of fuel rods is divided into four fuel rod group regions of small fuel rod bundles by a cross-shaped partitioning structure consisting of paired plate-like structures which connect two opposing surfaces of a channel box. A water removing material with less neutron absorption (for example, Zr or a Zr alloy) or a solid moderator is inserted and secured to a portion of a non-boiling water region interposed between the paired plate-like structure. It has a structure that light water flows to the region in the plate-like structure. The volume, density or composition of the water removing material is controlled depending on the composition of the fuels, to change the moderating characteristics of neutrons in the non-boiling water region. This can easily moderate the difference of nuclear characteristics between each of fuel assemblies using fuel materials of different fuel compositions. Further, the reactivity control effect of the burnable poisons can be enhanced without worsening fuel economy or linear power density. (I.N.)

Impact of fuel composition on the recirculation zone structure and its role in lean premixed flame anchoring

KAUST Repository

Hong, Seunghyuck

2015-01-01

© 2014 The Combustion Institute. Published by Elsevier Inc. All rights reserved. We investigate the dependence of the recirculation zone (RZ) size and structure on the fuel composition using high-speed particle image velocimetry (PIV) and chemiluminescence measurements for C3H8/H2/air lean premixed flames stabilized in a backward-facing step combustor. Results show an intricate coupling between the flame anchoring and the RZ structure and length. For a fixed fuel composition, at relatively low equivalence ratios, the time-averaged RZ is comprised of two counter rotating eddies: a primary eddy (PE) between the shear layer and the bottom wall; and a secondary eddy (SE) between the vertical step wall and the PE. The flame stabilizes downstream of the saddle point of the dividing streamline between the two eddies. As equivalence ratio is raised, the flame moves upstream, pushing the saddle point with it and reducing the size of the SE. Higher temperature of the products reduces the velocity gradient in the shear layer and thus the reattachment length. As equivalence ratio approaches a critical value, the saddle point reaches the step and the SE collapses while the flame starts to exhibit periodic flapping motions, suggesting a correlation between the RZ structure and flame anchoring. The overall trend in the flow field is the same as we add hydrogen to the fuel at a fixed equivalence ratio, demonstrating the impact of fuel composition on the flow field. We show that the reattachment lengths (LR), which are shown to encapsulate the mean RZ structure, measured over a range of fuel composition and equivalence ratio collapse if plotted against the strained consumption speed (Sc). Results indicate that for the flame to remain anchored, the RZ structure should satisfy lR,isothermal/L R,reacting · S c/U ∞ ∼ 0.1. If this criterion cannot be met, the flame blows off, flashes back or becomes thermoacoustically unstable, suggesting a Damköhler-like criterion for

Mathematical micro-model of a solid oxide fuel cell composite cathode

International Nuclear Information System (INIS)

Kenney, B.; Karan, K.

2004-01-01

In a solid oxide fuel cell (SOFC), the cathode processes account for a majority of the overall electrochemical losses. A composite cathode comprising a mixture of ion-conducting electrolyte and electron-conducting electro-catalyst can help minimize cathode losses provided microstructural parameters such as particle-size, composition, and porosity are optimized. The cost of composite cathode research can be greatly reduced by incorporating mathematical models into the development cycle. Incorporated with reliable experimental data, it is possible to conduct a parametric study using a model and the predicted results can be used as guides for component design. Many electrode models treat the cathode process simplistically by considering only the charge-transfer reaction for low overpotentials or the gas-diffusion at high overpotentials. Further, in these models an average property of the cathode internal microstructure is assumed. This paper will outline the development of a 1-dimensional SOFC composite cathode micro-model and the experimental procedures for obtaining accurate parameter estimates. The micro-model considers the details of the cathode microstructure such as porosity, composition and particle-size of the ionic and electronic phases, and their interrelationship to the charge-transfer reaction and mass transport processes. The micro-model will be validated against experimental data to determine its usefulness for performance prediction. (author)

Investigation on fabrication of SiC/SiC composite as a candidate material for fuel sub-assembly

International Nuclear Information System (INIS)

Lee, Jae-Kwang; Naganuma, Masayuki; Park, Joon-Soo; Kohyama, Akira

2005-01-01

The possibility of SiC/SiC (Silicon carbide fiber reinforced Silicon carbide) composites application for fuel sub-assembly of Fast Breeder Reactor was investigated. To select a raw material of SiC/SiC composites, a few kinds of SiC nano powder was estimated by SEM observation and XRD analysis. Furthermore, SiC monolithic was sintered from them and estimated by flexural test. SiC nano-powder which showed good sinterability, it was used for fabrication of SiC/SiC composites by Hot Pressing method. From the sintering condition of 1800, 1820degC temperature and 15, 20 MPa pressure, SiC/SiC composite was fabricated and then estimated by tensile test. SiC/SiC composite, which made by 1820degC and 20 MPa condition, showed the highest mechanical strength by the monotonic tensile test. SiC/SiC composite, which made by 1800degC and 15 MPa condition, showed a stable fracture behavior at the monotonic and cyclic tensile test. And then, the hoop stress of ideal model of SiC/SiC composites was discussed. It was confirmed that applicability of SiC/SiC composites by Hot Pressing method for fuel sub-assembly structural material. To make it real attractive one, to maintain the reliability and safety as a high temperature structural material, the design and process study on SiC/Sic composites material will be continued. (author)

Isoprenoid based alternative diesel fuel

Science.gov (United States)

Lee, Taek Soon; Peralta-Yahya, Pamela; Keasling, Jay D.

2015-08-18

Fuel compositions are provided comprising a hydrogenation product of a monocyclic sesquiterpene (e.g., hydrogenated bisabolene) and a fuel additive. Methods of making and using the fuel compositions are also disclosed. ##STR00001##

Highly conductive composites for fuel cell flow field plates and bipolar plates

Science.gov (United States)

Jang, Bor Z; Zhamu, Aruna; Song, Lulu

2014-10-21

This invention provides a fuel cell flow field plate or bipolar plate having flow channels on faces of the plate, comprising an electrically conductive polymer composite. The composite is composed of (A) at least 50% by weight of a conductive filler, comprising at least 5% by weight reinforcement fibers, expanded graphite platelets, graphitic nano-fibers, and/or carbon nano-tubes; (B) polymer matrix material at 1 to 49.9% by weight; and (C) a polymer binder at 0.1 to 10% by weight; wherein the sum of the conductive filler weight %, polymer matrix weight % and polymer binder weight % equals 100% and the bulk electrical conductivity of the flow field or bipolar plate is at least 100 S/cm. The invention also provides a continuous process for cost-effective mass production of the conductive composite-based flow field or bipolar plate.

IFR fuel cycle

International Nuclear Information System (INIS)

Battles, J.E.; Miller, W.E.; Lineberry, M.J.; Phipps, R.D.

1992-01-01

The next major milestone of the IFR program is engineering-scale demonstration of the pyroprocess fuel cycle. The EBR-II Fuel Cycle Facility has just entered a startup phase, which includes completion of facility modifications and installation and cold checkout of process equipment. This paper reviews the development of the electrorefining pyroprocess, the design and construction of the facility for the hot demonstration, the design and fabrication of the equipment, and the schedule and initial plan for its operation

A Fast Numerical Method for the Calculation of the Equilibrium Isotopic Composition of a Transmutation System in an Advanced Fuel Cycle

Directory of Open Access Journals (Sweden)

F. Álvarez-Velarde

2012-01-01

Full Text Available A fast numerical method for the calculation in a zero-dimensional approach of the equilibrium isotopic composition of an iteratively used transmutation system in an advanced fuel cycle, based on the Banach fixed point theorem, is described in this paper. The method divides the fuel cycle in successive stages: fuel fabrication, storage, irradiation inside the transmutation system, cooling, reprocessing, and incorporation of the external material into the new fresh fuel. The change of the fuel isotopic composition, represented by an isotope vector, is described in a matrix formulation. The resulting matrix equations are solved using direct methods with arbitrary precision arithmetic. The method has been successfully applied to a double-strata fuel cycle with light water reactors and accelerator-driven subcritical systems. After comparison to the results of the EVOLCODE 2.0 burn-up code, the observed differences are about a few percents in the mass estimations of the main actinides.

Modelling the bending/bowing of composite beams such as nuclear fuel

International Nuclear Information System (INIS)

Tayal, M.

1989-01-01

Arrays of tubes are used in many engineered structures, such as in nuclear fuel bundles and in steam generators. The tubes can bend (bow) due to in-service temperatures and loads. Assessments of bowing of nuclear fuel elements can help demonstrate the integrity of fuel and of surrounding components, as a function of operating conditions such as channel power. The BOW code calculates the bending of composite beams such as fuel elements, due to gradients of temperature and due to hydraulic forces. The deflections and rotations are calculated in both lateral directions, for given conditions of temperatures. Wet and dry operation of the sheath can be simulated. BOW accounts for the following physical phenomena: circumferential and axial variations in the temperatures of the sheath and of the pellet; cracking of pellets; grip and slip between the pellets and the sheath; hydraulic drag; restraint from endplates, from neighbouring elements, and from the pressure-tube; gravity; concentric or eccentric welds between endcaps and endplate; neutron flux gradients; and variations of material properties with temperature. The code is based on fundamental principles of mechanics. The governing equations are solved numerically using the finite element method. Several comparisons with closed-form equations shoe that the solutions of BOW are accurate. BOW's predictions for initial in-reactor bow are also consistent with two post-irradiation measurements

Vibratory-compacted (vipac/sphere-pac) nuclear fuels - a comparison with pelletized nuclear fuels

Energy Technology Data Exchange (ETDEWEB)

Chidester, K.; Rubin, J. [Los Alamos National Lab., NM (United States); Thompson, M

2001-07-01

In order to achieve the packing densities required for nuclear fuel stability, economy and performance, the fuel material must be densified. This has traditionally been performed by high-temperature sintering. (At one time, fuel densification was investigated using cold/hot swaging. However, this fabrication method has become uncommon.) Alternatively, fuel can be densified by vibratory compaction (VIPAC). During the late 1950's and into the 1970's, in the U.S., vibratory compaction fuel was fabricated and test irradiated to evaluate its applicability compared to the more traditional pelletized fuel for nuclear reactors. These activities were primarily focused on light water reactors (LWR) but some work was performed for fast reactors. This paper attempts to summarize these evaluations and proposes to reconsider VIPAC fuel for future use. (author)

Vibratory-compacted (vipac/sphere-pac) nuclear fuels - a comparison with pelletized nuclear fuels

International Nuclear Information System (INIS)

Chidester, K.; Rubin, J.; Thompson, M.

2001-01-01

In order to achieve the packing densities required for nuclear fuel stability, economy and performance, the fuel material must be densified. This has traditionally been performed by high-temperature sintering. (At one time, fuel densification was investigated using cold/hot swaging. However, this fabrication method has become uncommon.) Alternatively, fuel can be densified by vibratory compaction (VIPAC). During the late 1950's and into the 1970's, in the U.S., vibratory compaction fuel was fabricated and test irradiated to evaluate its applicability compared to the more traditional pelletized fuel for nuclear reactors. These activities were primarily focused on light water reactors (LWR) but some work was performed for fast reactors. This paper attempts to summarize these evaluations and proposes to reconsider VIPAC fuel for future use. (author)

Study of the equilibrium of air-blown gasification of biomass to coal evolution fuels

International Nuclear Information System (INIS)

Biagini, Enrico

2016-01-01

Highlights: • Equilibrium model validated for coals, torrefied/green biomasses, in different gasifiers. • Maps of syngas composition, LHV and CGE for ER = 0–0.6, T = 500–2000 K, EBP = 0.004–0.158. • Effect of unconverted carbon, fuel moisture and overoxidation quantified. • Parameters for the maximum efficiency determined as functions of EBP. • EBP proven to be a good parameter for the quantitative comparison of different fuels. - Abstract: A non-stoichiometric equilibrium model based on the minimization of the Gibbs free energy was used to study the isothermal and adiabatic air-blown gasification of solid fuels on a carbonization curve from fossil (hard/brown coals, peat) to renewable (green biomasses and cellulose) fuels, including torrefied biofuels. The maps of syngas composition, heating value and process efficiency were provided as functions of equivalent ratio (oxygen-to-fuel ratio) in the range 0–0.6, temperature in 500–2000 K, and a fuel parameter, which allowed different cases to be quantitatively compared. The effect of fuel moisture, unconverted carbon and conditions to limit the tar formation was also studied. Cold gas efficiency >0.75 can be achieved for coals at high temperature, using entrained beds (which give low unconverted carbon), and improved by moisture/added steam. The bigger efficiency of green biomasses is only potential, as the practical limits (high temperature required to limit tar formation, moisture content and unconverted carbon in small gasifiers) strongly reduce the gasification performance. Torrefied biomasses (and plastics having an intermediate fuel parameter between coals and green biomasses) can attain high efficiency also in real conditions. The results shown in this work can be useful to evaluate the most promising feedstock (depending on its composition and possible pre-treatment/upgrading), define the operating conditions for maximizing the syngas heating value or the global efficiency, assess the

Parametric Evaluation of SiC/SiC Composite Cladding with UO2 Fuel for LWR Applications: Fuel Rod Interactions and Impact of Nonuniform Power Profile in Fuel Rod

Science.gov (United States)

Singh, G.; Sweet, R.; Brown, N. R.; Wirth, B. D.; Katoh, Y.; Terrani, K.

2018-02-01

SiC/SiC composites are candidates for accident tolerant fuel cladding in light water reactors. In the extreme nuclear reactor environment, SiC-based fuel cladding will be exposed to neutron damage, significant heat flux, and a corrosive environment. To ensure reliable and safe operation of accident tolerant fuel cladding concepts such as SiC-based materials, it is important to assess thermo-mechanical performance under in-reactor conditions including irradiation and realistic temperature distributions. The effect of non-uniform dimensional changes caused by neutron irradiation with spatially varying temperatures, along with the closing of the fuel-cladding gap, on the stress development in the cladding over the course of irradiation were evaluated. The effect of non-uniform circumferential power profile in the fuel rod on the mechanical performance of the cladding is also evaluated. These analyses have been performed using the BISON fuel performance modeling code and the commercial finite element analysis code Abaqus. A constitutive model is constructed and solved numerically to predict the stress distribution in the cladding under normal operating conditions. The dependence of dimensions and thermophysical properties on irradiation dose and temperature has been incorporated into the models. Initial scoping results from parametric analyses provide time varying stress distributions in the cladding as well as the interaction of fuel rod with the cladding under different conditions of initial fuel rod-cladding gap and linear heat rate. It is found that a non-uniform circumferential power profile in the fuel rod may cause significant lateral bowing in the cladding, and motivates further analysis and evaluation.

Hanford spent nuclear fuel cold vacuum drying proof of performance test procedure

International Nuclear Information System (INIS)

McCracken, K.J.

1998-01-01

This document provides the test procedure for cold testing of the first article skids for the Cold Vacuum Drying (CVD) process at the Facility. The primary objective of this testing is to confirm design choices and provide data for the initial start-up parameters for the process. The current scope of testing in this document includes design verification, drying cycle determination equipment performance testing of the CVD process and MCC components, heat up and cool-down cycle determination, and thermal model validation

An optimum cold end configuration for helium liquefaction cycles

International Nuclear Information System (INIS)

Minta, M.; Smith, J.L.

1984-01-01

This chapter examines the effect of the non-ideal behavior of helium at low temperature on the performance of helium liquefaction cycles. The effect is isolated by means of a continuum model for the precooling stage. The cold end losses are due primarily to the composite effect of the non-ideality of helium at low temperatures and the heat exchanger losses, in addition to the component losses fixed by the expander/compressor efficiencies. Topics considered include continuously distributed full-pressure ratio expanders, continuously distributed full-flow expanders, the heat exchange effect (ideal gas working fluid, real gas working fluid), and cold end configuration. The cold end configuration minimizes the cycle cold end losses

Anticorrosion Coating of Carbon Nanotube/Polytetrafluoroethylene Composite Film on the Stainless Steel Bipolar Plate for Proton Exchange Membrane Fuel Cells

Directory of Open Access Journals (Sweden)

Yoshiyuki Show

2013-01-01

Full Text Available Composite film of carbon nanotube (CNT and polytetrafluoroethylene (PTFE was formed from dispersion fluids of CNT and PTFE. The composite film showed high electrical conductivity in the range of 0.1–13 S/cm and hydrophobic nature. This composite film was applied to stainless steel (SS bipolar plates of the proton exchange membrane fuel cell (PEMFC as anticorrosion film. This coating decreased the contact resistance between the surface of the bipolar plate and the membrane electrode assembly (MEA of the PEMFC. The output power of the fuel cell is increased by 1.6 times because the decrease in the contact resistance decreases the series resistance of the PEMFC. Moreover, the coating of this composite film protects the bipolar plate from the surface corrosion.

Exhaust Emission Characteristics of Heavy Duty Diesel Engine During Cold and Warm Start

Directory of Open Access Journals (Sweden)

YANG Rong

2014-07-01

Full Text Available Through experiment conducted on a six cylinder direct injection diesel engine with SCR catalyst, effects of coolant temperature on rail pressure, injection quantity, excess air coefficient and emissions characteristics during cold and warm start were investigated. The results showed that, the maximum injection quantity during a starting event was several times higher than idling operation mode, so was the maximal opacity in the cold and warm starting process. When coolant temperature rose up to above 20℃, NOX emissions in the starting process exhibited peculiar rise which was times higher than idling mode. Compared with engine warm start, rail pressure, cycle fuel quantity, opacity, CO and HC emissions during engine cold start were higher in the course from their transient maximal values towards stabilized idling status. NOX in the same transient course, however, were lower in cold start. As coolant temperature rose, the maximal and the idling value of rail pressure and cycle fuel injection quantity during diesel engine starting process decreased gradually, the excess air coefficient increased to a certain degree, and the maximal and idling values of NOX increased gradually.

Optimization of Domestic-Size Renewable Energy System Designs Suitable for Cold Climate Regions

Science.gov (United States)

Akpan, Itoro Etim; Sasaki, Masafumi; Endoh, Noboru

Five different kinds of domestic-size renewable energy system configurations for very cold climate regions were investigated. From detailed numerical modeling and system simulations, it was found that the consumption of fuel oil for the auxiliary boiler in residential-type households can almost be eliminated with a renewable energy system that incorporates photovoltaic panel arrays for electricity generation and two storage tanks: a well-insulated electric water storage tank that services the hot water loads, and a compact boiler/geothermal heat pump tank for room heating during very cold seasons. A reduction of Greenhouse Gas Emissions (GHG) of about 28% was achieved for this system compared to an equivalent conventional system. The near elimination of the use of fuel oil in this system makes it very promising for very cold climate regions in terms of energy savings because the running cost is not so dependent on the unstable nature of global oil prices.

[Bonding strength of resin and tooth enamel after teeth bleaching with cold plasma].

Science.gov (United States)

Zhu, Meng-meng; Wang, Guo-min; Sun, Ke; Li, Ying-long; Pan, Jie

2016-02-18

To investigate the immediate bond strength and surface structure of resin and the tooth enamel which treated by cold plasma. In the study, 40 bovine incisors were divided into two equal parts. In this sense, all enamel adhesive samples were prepared and then randomly divided into 4 groups (n =20). group 1: acid + single bond 2+resin composite (control group); group 2:beyond bleaching+ acid+single bond 2+resin composite; group 3: treated by cold plasma for 5 minutes+ acid+single bond 2+resin composite; group 4: treated by cold plasma for 5 minutes+single bond 2+resin composite. Single bond 2 bonding system and Filtek Z250 resin were used in this experiment. The shear bond strength was tested by universal testing machine. The surface of the enamel in different processes was observed by scanning electron microscope (SEM). Statistical analyses by the single factor analysis of variance and multiple pairwise comparisons were performed with SPSS 17.0 . The shear bond strength of group 4 (8.60 MPa) was significantly lower than that of the other three groups (Penamel treated by cold plasma had slight molten form, which was different from etched enamel surface.The fractured surface of group 3 was mix fracture, which was similar to the control group (group 1). Compared with the conventional clinic bleaching, immediate bond strength of resin-enamel that treated by cold plasma has not been affected.

Multilayered sulphonated polysulfone/silica composite membranes for fuel cell applications

International Nuclear Information System (INIS)

Padmavathi, Rajangam; Karthikumar, Rajendhiran; Sangeetha, Dharmalingam

2012-01-01

Highlights: ► Multilayered membranes were fabricated with SPSu. ► Aminated polysulfone and silica were used as the layers in order to prevent the crossover of methanol. ► The methanol permeability and selectivity ratio proved a strong influence on DMFC application. ► The suitability of the multilayered membranes was studied in the lab made set-ups of PEMFC and DMFC. - Abstract: Polymer electrolyte membranes used in proton exchange membrane fuel cell (PEMFC) and direct methanol fuel cell (DMFC) suffer from low dimensional stability. Hence multilayered membranes using sulfonated polysulfone (SPSu) and silica (SiO 2 ) were fabricated to alter such properties. The introduction of an SiO 2 layer between two layers of SPSu to form the multilayered composite membrane enhanced its dimensional stability, but slightly lowered its proton conductivity when compared to the conventional SPSu/SiO 2 composite membrane. Additionally, higher water absorption, lower methanol permeability and higher flame retardancy were also observed in this newly fabricated multilayered membrane. The performance evaluation of the 2 wt% SiO 2 loaded multilayered membrane in DMFC showed a maximum power density of 86.25 mW cm −2 , which was higher than that obtained for Nafion 117 membrane (52.8 mW cm −2 ) in the same single cell test assembly. Hence, due to the enhanced dimensional stability, reduced methanol permeability and higher maximum power density, the SPSu/SiO 2 /SPSu multilayered membrane can be a viable and a promising candidate for use as an electrolyte membrane in DMFC applications, when compared to Nafion.

Advanced Collimators for Verification of the Pu Isotopic Composition in Fresh Fuel by High Resolution Gamma Spectrometry

International Nuclear Information System (INIS)

Lebrun, Alain; Berlizov, Andriy

2013-06-01

IAEA verification of the nuclear material contained in fresh nuclear fuel assemblies is usually based on neutron coincidence counting (NCC). In the case of uranium fuel, active NCC provides the total content of uranium-235 per unit of length which, combined with active length verification, fully supports the verification. In the case of plutonium fuel, passive NCC provides the plutonium-240 equivalent content which needs to be associated with a measurement of the isotopic composition and active length measurement to complete the verification. Plutonium isotopic composition is verified by high resolution gamma spectrometry (HRGS) applied on fresh fuel assemblies assuming all fuel rods are fabricated from the same plutonium batch. For particular verifications when such an assumption cannot be reasonably made, there is a need to optimize the HRGS measurement so that contributions of internal rods to the recorded spectrum are maximized, thus providing equally strong verification of the internal fuel rods. This paper reports on simulation work carried out to design special collimators aimed at reducing the relative contribution of external fuel rods while enhancing the signal recorded from internal rods. Both cases of square lattices (e.g. 17x17 pressurized water reactor (PWR) fuel) and hexagonal compact lattices (e.g. BN800 fast neutron reactor (FNR) fuel) have been addressed. In the case of PWR lattices, the relatively large optical path to internal pins compensates for low plutonium concentrations and the large size of the fuel assemblies. A special collimator based on multiple, asymmetrical, vertical slots allows recording a spectrum from internal rods only when needed. In the FNR case, the triangular lattice is much more compact and the optical path to internal rods is very narrow. However, higher plutonium concentration and use of high energy ranges allow the verification of internal rods to be significantly strengthened. Encouraging results from the simulation

Process engineering of ceramic composite coatings for fuel cell systems

Energy Technology Data Exchange (ETDEWEB)

Li, G.; Kim, H.; Chen, M.; Yang, Q.; Troczynski, T. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Metals and Materials Engineering

2003-07-01

Researchers at UBCeram at the Department of Metals and Materials Engineering at the University of British Columbia have developed a technology to chemically bond composite sol-gel (CB-CSG) coating onto metallic surfaces of complex or concave shapes. The process has been optimized for electrically resistive coatings and corrosion-resistant coatings. The CSG is sprayed onto metallic surfaces and is heat-treated at 300 degrees C to partially dehydrate the hydroxides. The CSG film is then chemically bonded through reaction of active alumina with metal phosphates, such as aluminium phosphate. A new chromate-free process is being developed to address the issue of coatings porosity. The electrodeposition technique involves polymer particles mixed with suspended fine alumina particles which are co-deposited by electrophoretic means or by electrocoagulation. The composite e-coatings have excellent mechanical properties and are being considered as a protective coating for various components of fuel cell systems. 9 refs., 7 figs.

Structural Study of Reduced Graphene Oxide/ Polypyrrole Composite as Methanol Sensor in Direct Methanol Fuel Cell

International Nuclear Information System (INIS)

Mumtazah Atiqah Hassan; Siti Kartom Kamarudin; Siti Kartom Kamarudin

2016-01-01

Density functional theory (DFT) computations were performed on the optimized geometric and electronic properties of reduced graphene oxide/polypyrole (rGO/ PPy) composite in comparison with pure graphene and graphene oxide structures. Incorporation of both reduced GO (rGO) and PPy will form a good composite which have advantages from both materials such as good mechanical strength and excellent electrical conductivity. These composite would be very suitable in fabrication of methanol sensor in direct methanol fuel cell (DMFC). The HOMO-LUMO energy (eV) was also calculated. These computations provide a theoretical explanation for the good performance of rGO/ PPy composite as electrode materials in methanol sensor. (author)

Ten residual biomass fuels for circulating fluidized-bed gasification

Energy Technology Data Exchange (ETDEWEB)

Drift, A. van der; Doorn, J. van [Netherlands Energy Research Foundation (ECN), Petten (Netherlands); Vermeulen, J.W. [NV Afvalzorg, Haarlem (Netherlands)

2001-07-01

In co-operation with a Dutch company (NV Afvalzorg) and the Dutch agency for energy and environment (Novem), ECN has successfully tested 10 different biomass residues in its 500 kW{sub th} circulating fluidized-bed gasification facility. Among the fuels used as demolition wood (both puree and mixed with sewage sludge and paper sludge), verge grass, railroad ties, cacao shells and different woody fuels. Railroad ties turn out to contain very little (heavy) metals. Initially, fuel feeding problems often impeded smooth operation. Contrary to feeding systems, the circulating fluidized-bed gasification process itself seems very flexible concerning the conversion of different kinds of biomass fuels. The fuel moisture content is one of the most important fuel characteristics. More moisture means that more air is needed to maintain the process temperature resulting in better carbon conversion and lower tar emission but also lower product gas heating value and lower cold gas efficiency. So, for a good comparison of the gasification behaviour of different fuels, the moisture content should be similar. However, the moisture content should be defined on an ash-free basis rather than on total mass (the usual way). Some of the ashes produced and retained in the second cyclone were analysed both for elemental composition and leaching behaviour. It turned out that the leaching rate of Mo and Br, elements only present in small concentrations, are preventing the ash to be considered as inert material according to the Dutch legislation for dumping on landfill sites. (Author)

Production of diesel fuels from vegetable oils by means of homogenous catalysed metathesis of methyl oleate; Gewinnung von dieselartigen Kraftstoffen aus Pflanzenoelen mittels homogen katalysierter Metathese von Methyloleat

Energy Technology Data Exchange (ETDEWEB)

Erben, Friedrich; Paetzold, Eckhard [Rostock Univ. (Germany). Leibniz-Institut fuer Katalyse; Schuemann, Ulrike; Wichmann, Volker; Fluegge, Evelyn; Berndt, Silvia; Harndorf, Horst [Rostock Univ. (Germany). Lehrstuhl fuer Kolbenmaschinen und Verbrennungsmotoren; Kragl, Udo [Rostock Univ. (Germany). Leibniz-Institut fuer Katalyse; Rostock Univ. (Germany). Inst. fuer Chemie

2013-10-01

Due to the increasing shortage of fossil combustibles renewable resources like oils and fats have great potential for the production of diesel-like fuels. A key step in adapting the properties of biogenic fuels to those from fossil sources is cracking or isomerisation of linear hydrocarbon chains. This is necessary for optimal cold flow properties and a continuously rising boiling curve. The present work describes the potential of metathesis for this purpose. By formal exchange of parts of molecules of a small number of starting materials a variety of products is formed which exhibit a fuel-like composition. Ethenolysis as well as hexenolysis is examined, whereat hexenolysis owns the greater potential for production of diesel-like fuels out of unsaturated fatty acid esters. (orig.)

Recycle of valuable products from oily cold rolling mill sludge

Science.gov (United States)

Liu, Bo; Zhang, Shen-gen; Tian, Jian-jun; Pan, De-an; Liu, Yang; Volinsky, Alex A.

2013-10-01

Oily cold rolling mill (CRM) sludge contains lots of iron and alloying elements along with plenty of hazardous organic components, which makes it as an attractive secondary source and an environmental contaminant at the same time. The compound methods of "vacuum distillation + oxidizing roasting" and "vacuum distillation + hydrogen reduction" were employed for the recycle of oily cold rolling mill sludge. First, the sludge was dynamically vacuum distilled in a rotating furnace at 50 r/min and 600°C for 3 h, which removed almost hazardous organic components, obtaining 89.2wt% ferrous resultant. Then, high purity ferric oxide powders (99.2wt%) and reduced iron powders (98.9wt%) were obtained when the distillation residues were oxidized and reduced, respectively. The distillation oil can be used for fuel or chemical feedstock, and the distillation gases can be collected and reused as a fuel.

FABRICATION AND MATERIAL ISSUES FOR THE APPLICATION OF SiC COMPOSITES TO LWR FUEL CLADDING

Directory of Open Access Journals (Sweden)

WEON-JU KIM

2013-08-01

Full Text Available The fabrication methods and requirements of the fiber, interphase, and matrix of nuclear grade SiCf/SiC composites are briefly reviewed. A CVI-processed SiCf/SiC composite with a PyC or (PyC-SiCn interphase utilizing Hi-Nicalon Type S or Tyranno SA3 fiber is currently the best combination in terms of the irradiation performance. We also describe important material issues for the application of SiC composites to LWR fuel cladding. The kinetics of the SiC corrosion under LWR conditions needs to be clarified to confirm the possibility of a burn-up extension and the cost-benefit effect of the SiC composite cladding. In addition, the development of end-plug joining technology and fission products retention capability of the ceramic composite tube would be key challenges for the successful application of SiC composite cladding.

Usage of burnt fuel isotopic compositions from engineering codes in Monte-Carlo code calculations

International Nuclear Information System (INIS)

Aleshin, Sergey S.; Gorodkov, Sergey S.; Shcherenko, Anna I.

2015-01-01

A burn-up calculation of VVER's cores by Monte-Carlo code is complex process and requires large computational costs. This fact makes Monte-Carlo codes usage complicated for project and operating calculations. Previously prepared isotopic compositions are proposed to use for the Monte-Carlo code (MCU) calculations of different states of VVER's core with burnt fuel. Isotopic compositions are proposed to calculate by an approximation method. The approximation method is based on usage of a spectral functionality and reference isotopic compositions, that are calculated by engineering codes (TVS-M, PERMAK-A). The multiplication factors and power distributions of FA and VVER with infinite height are calculated in this work by the Monte-Carlo code MCU using earlier prepared isotopic compositions. The MCU calculation data were compared with the data which were obtained by engineering codes.

Combustible structural composites and methods of forming combustible structural composites

Science.gov (United States)

Daniels, Michael A.; Heaps, Ronald J.; Steffler, Eric D.; Swank, W. David

2013-04-02

Combustible structural composites and methods of forming same are disclosed. In an embodiment, a combustible structural composite includes combustible material comprising a fuel metal and a metal oxide. The fuel metal is present in the combustible material at a weight ratio from 1:9 to 1:1 of the fuel metal to the metal oxide. The fuel metal and the metal oxide are capable of exothermically reacting upon application of energy at or above a threshold value to support self-sustaining combustion of the combustible material within the combustible structural composite. Structural-reinforcing fibers are present in the composite at a weight ratio from 1:20 to 10:1 of the structural-reinforcing fibers to the combustible material. Other embodiments and aspects are disclosed.

Fuel Thermo-physical Characterization Project: Evaluation of Models to Calculate Thermal Diffusivity of Layered Composites

Energy Technology Data Exchange (ETDEWEB)

Burkes, Douglas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Amanda J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gardner, Levi D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Andrew M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Huber, Tanja K. [Technische Universität München, Munich (Germany); Breitkreutz, Harald [Technische Universität München, Munich (Germany)

2015-02-11

The Office of Material Management and Minimization Fuel Thermo-physical Characterization Project at Pacific Northwest National Laboratory (PNNL) is tasked with using PNNL facilities and processes to receive irradiated low enriched uranium-molybdenum fuel plate samples and perform analyses in support of the Office of Material Management and Minimization Reactor Conversion Program. This work is in support of the Fuel Development Pillar that is managed by Idaho National Laboratory. A key portion of the scope associated with this project was to measure the thermal properties of fuel segments harvested from plates that were irradiated in the Advanced Test Reactor. Thermal diffusivity of samples prepared from the fuel segments was measured using laser flash analysis. Two models, one developed by PNNL and the other developed by the Technische Universität München (TUM), were evaluated to extract the thermal diffusivity of the uranium-molybdenum alloy from measurements made on the irradiated, layered composites. The experimental data of the “TC” irradiated fuel segment was evaluated using both models considering a three-layer and five-layer system. Both models are in acceptable agreement with one another and indicate that the zirconium diffusion barrier has a minimal impact on the overall thermal diffusivity of the monolithic U-Mo fuel.

Correlation of rocket propulsion fuel properties with chemical composition using comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry followed by partial least squares regression analysis.

Science.gov (United States)

Kehimkar, Benjamin; Hoggard, Jamin C; Marney, Luke C; Billingsley, Matthew C; Fraga, Carlos G; Bruno, Thomas J; Synovec, Robert E

2014-01-31

There is an increased need to more fully assess and control the composition of kerosene-based rocket propulsion fuels such as RP-1. In particular, it is critical to make better quantitative connections among the following three attributes: fuel performance (thermal stability, sooting propensity, engine specific impulse, etc.), fuel properties (such as flash point, density, kinematic viscosity, net heat of combustion, and hydrogen content), and the chemical composition of a given fuel, i.e., amounts of specific chemical compounds and compound classes present in a fuel as a result of feedstock blending and/or processing. Recent efforts in predicting fuel chemical and physical behavior through modeling put greater emphasis on attaining detailed and accurate fuel properties and fuel composition information. Often, one-dimensional gas chromatography (GC) combined with mass spectrometry (MS) is employed to provide chemical composition information. Building on approaches that used GC-MS, but to glean substantially more chemical information from these complex fuels, we recently studied the use of comprehensive two dimensional (2D) gas chromatography combined with time-of-flight mass spectrometry (GC×GC-TOFMS) using a "reversed column" format: RTX-wax column for the first dimension, and a RTX-1 column for the second dimension. In this report, by applying chemometric data analysis, specifically partial least-squares (PLS) regression analysis, we are able to readily model (and correlate) the chemical compositional information provided by use of GC×GC-TOFMS to RP-1 fuel property information such as density, kinematic viscosity, net heat of combustion, and so on. Furthermore, we readily identified compounds that contribute significantly to measured differences in fuel properties based on results from the PLS models. We anticipate this new chemical analysis strategy will have broad implications for the development of high fidelity composition-property models, leading to an

Spent nuclear fuel project cold vacuum drying facility supporting data and calculation database

International Nuclear Information System (INIS)

IRWIN, J.J.

1999-01-01

This document provides a database of supporting calculations for the Cold Vacuum Drying Facility (CVDF). The database was developed in conjunction with HNF-SD-SNF-SAR-002, ''Safety Analysis Report for the Cold Vacuum Drying Facility'', Phase 2, ''Supporting Installation of Processing Systems'' (Garvin 1998). The HNF-SD-SNF-DRD-002, 1997, ''Cold Vacuum Drying Facility Design Requirements'', Rev. 2, and the CVDF Summary Design Report. The database contains calculation report entries for all process, safety and facility systems in the CVDF, a general CVD operations sequence and the CVDF System Design Descriptions (SDDs). This database has been developed for the SNFP CVDF Engineering Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved

Online gas composition estimation in solid oxide fuel cell systems with anode off-gas recycle configuration

Science.gov (United States)

Dolenc, B.; Vrečko, D.; Juričić, Ð.; Pohjoranta, A.; Pianese, C.

2017-03-01

Degradation and poisoning of solid oxide fuel cell (SOFC) stacks are continuously shortening the lifespan of SOFC systems. Poisoning mechanisms, such as carbon deposition, form a coating layer, hence rapidly decreasing the efficiency of the fuel cells. Gas composition of inlet gases is known to have great impact on the rate of coke formation. Therefore, monitoring of these variables can be of great benefit for overall management of SOFCs. Although measuring the gas composition of the gas stream is feasible, it is too costly for commercial applications. This paper proposes three distinct approaches for the design of gas composition estimators of an SOFC system in anode off-gas recycle configuration which are (i.) accurate, and (ii.) easy to implement on a programmable logic controller. Firstly, a classical approach is briefly revisited and problems related to implementation complexity are discussed. Secondly, the model is simplified and adapted for easy implementation. Further, an alternative data-driven approach for gas composition estimation is developed. Finally, a hybrid estimator employing experimental data and 1st-principles is proposed. Despite the structural simplicity of the estimators, the experimental validation shows a high precision for all of the approaches. Experimental validation is performed on a 10 kW SOFC system.

Mountain Warfare and Cold Weather Operations

Science.gov (United States)

2016-04-29

is important to determine whether the bottom is composed of sand, gravel, silt, clay , or rock and in what proportions. For more information see ATP...these planning factors by about two quarts per individual. 6-22. Water increases in viscosity in extreme cold weather, and therefore moves slower...In arctic conditions, fuel spilled on flesh can cause instant frostbite if the proper gloves are not worn. 6-32. Multi- viscosity oil (15W-40) is

Lipid-induced thermogenesis is up-regulated by the first cold-water immersions in juvenile penguins.

Science.gov (United States)

Teulier, Loïc; Rey, Benjamin; Tornos, Jérémy; Le Coadic, Marion; Monternier, Pierre-Axel; Bourguignon, Aurore; Dolmazon, Virginie; Romestaing, Caroline; Rouanet, Jean-Louis; Duchamp, Claude; Roussel, Damien

2016-07-01

The passage from shore to marine life is a critical step in the development of juvenile penguins and is characterized by a fuel selection towards lipid oxidation concomitant to an enhancement of lipid-induced thermogenesis. However, mechanisms of such thermogenic improvement at fledging remain undefined. We used two different groups of pre-fledging king penguins (Aptenodytes patagonicus) to investigate the specific contribution of cold exposure during water immersion to lipid metabolism. Terrestrial penguins that had never been immersed in cold water were compared with experimentally cold-water immersed juveniles. Experimentally immersed penguins underwent ten successive immersions at approximately 9-10 °C for 5 h over 3 weeks. We evaluated adaptive thermogenesis by measuring body temperature, metabolic rate and shivering activity in fully immersed penguins exposed to water temperatures ranging from 12 to 29 °C. Both never-immersed and experimentally immersed penguins were able to maintain their homeothermy in cold water, exhibiting similar thermogenic activity. In vivo, perfusion of lipid emulsion at thermoneutrality induced a twofold larger calorigenic response in experimentally immersed than in never-immersed birds. In vitro, the respiratory rates and the oxidative phosphorylation efficiency of isolated muscle mitochondria were not improved with cold-water immersions. The present study shows that acclimation to cold water only partially reproduced the fuel selection towards lipid oxidation that characterizes penguin acclimatization to marine life.

Lead Isotopic Compositions of Selected Coals, Pb/Zn Ores and Fuels in China and the Application for Source Tracing.

Science.gov (United States)

Bi, Xiang-Yang; Li, Zhong-Gen; Wang, Shu-Xiao; Zhang, Lei; Xu, Rui; Liu, Jin-Ling; Yang, Hong-Mei; Guo, Ming-Zhi

2017-11-21

Lead (Pb) pollution emission from China is becoming a potential worldwide threat. Pb isotopic composition analysis is a useful tool to accurately trace the Pb sources of aerosols in atmosphere. In this study, a comprehensive data set of Pb isotopes for coals, Pb/Zn ores, and fuels from China was presented. The ratios of 206 Pb/ 207 Pb and 208 Pb/ 206 Pb in the coals were in the range of 1.114-1.383 and 1.791-2.317, similar to those from Europe, Oceania, and South Asia, but different from those from America (p fuels from in coals. Urban aerosols demonstrated similar Pb isotopic compositions to coals, Pb/Zn ores, and fuels in China. After removing the leaded gasoline, the Pb in aerosols is more radiogenic, supporting the heavy contribution of coal combustion to the atmospheric Pb pollution.

Analysis of the cold compaction behaviour of TiH2-316L nanocomposite powder blend using compaction models

CSIR Research Space (South Africa)

Machio, Christopher N

2015-07-01

Full Text Available The paper captures the effect of structure and the applicability of compaction models using the cold compaction of a TiH2-SS316L composite powder prepared by high energy mechanical milling. The composite blend was cold pressed uniaxially...

33 CFR 183.514 - Fuel tanks: Labels.

Science.gov (United States)

2010-07-01

...) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Equipment Standards § 183.514 Fuel tanks... accelerations the statement, “Must be installed aft of the boat's half length.” (c) Each letter and each number... water, oil, salt spray, direct sunlight, heat, cold, and wear expected in normal operation of the boat...

Feasibility of Carbon Fiber/PEEK Composites for Cryogenic Fuel Tank Applications

Science.gov (United States)

Doyle, K.; Doyle, A.; O Bradaigh, C. M.; Jaredson, D.

2012-07-01

This paper investigates the feasibility of CF/PEEK composites for manufacture of cryogenic fuel tanks for Next Generation Space Launchers. The material considered is CF/PEEK tape from Suprem SA and the proposed manufacturing process for the fuel tank is Automated Tape Placement. Material characterization was carried out on test laminates manufactured in an autoclave and also by Automated Tape Placement with in-situ consolidation. The results of the two processes were compared to establish if there is any knock down in properties for the automated tape placement process. A permeability test rig was setup with a helium leak detector and the effect of thermal cycling on the permeability properties of CF/PEEK was measured. A 1/10th scale demonstrator was designed and manufactured consisting of a cylinder manufactured by automated tape placement and an upper dome manufactured by autoclave processing. The assembly was achieved by Amorphous Interlayer Bonding with PEI.

Proton conductive montmorillonite-Nafion composite membranes for direct ethanol fuel cells

Science.gov (United States)

Wu, Xiu-Wen; Wu, Nan; Shi, Chun-Qing; Zheng, Zhi-Yuan; Qi, Hong-Bin; Wang, Ya-Fang

2016-12-01

The preparation of Nafion membranes modified with montmorillonites is less studied, and most relative works mainly applied in direct methanol fuel cells, less in direct ethanol fuel cells. Organic/inorganic composite membranes are prepared with different montmorillonites (Ca-montmorillonite, Na-montmorillonite, K-montmorillonite, Mg-montmorillonite, and H-montmorillonite) and Nafion solution via casting method at 293 K in air, and with balance of their proton conductivity and ethanol permeability. The ethanol permeability and proton conductivity of the membranes are comparatively studied. The montmorillonites can well decrease the ethanol permeability of the membranes via inserted them in the membranes, while less decrease the proton conductivities of the membranes depending on the inserted amount and type of montmorillonites. The proton conductivities of the membranes are between 36.0 mS/cm and 38.5 mS/cm. The ethanol permeability of the membranes is between 0.69 × 10-6 cm2/s and 2.67 × 10-6 cm2/s.

Design verification and validation plan for the cold vacuum drying facility

International Nuclear Information System (INIS)

NISHIKAWA, L.D.

1999-01-01

The Cold Vacuum Drying Facility (CVDF) provides the required process systems, supporting equipment, and facilities needed for drying spent nuclear fuel removed from the K Basins. This document presents the both completed and planned design verification and validation activities

Detection of cold pain, cold allodynia and cold hyperalgesia in freely behaving rats

Directory of Open Access Journals (Sweden)

Woolf Clifford J

2005-12-01

Full Text Available Abstract Background Pain is elicited by cold, and a major feature of many neuropathic pain states is that normally innocuous cool stimuli begin to produce pain (cold allodynia. To expand our understanding of cold induced pain states we have studied cold pain behaviors over a range of temperatures in several animal models of chronic pain. Results We demonstrate that a Peltier-cooled cold plate with ± 1°C sensitivity enables quantitative measurement of a detection withdrawal response to cold stimuli in unrestrained rats. In naïve rats the threshold for eliciting cold pain behavior is 5°C. The withdrawal threshold for cold allodynia is 15°C in both the spared nerve injury and spinal nerve ligation models of neuropathic pain. Cold hyperalgesia is present in the spared nerve injury model animals, manifesting as a reduced latency of withdrawal response threshold at temperatures that elicit cold pain in naïve rats. We also show that following the peripheral inflammation produced by intraplantar injection of complete Freund's adjuvant, a hypersensitivity to cold occurs. Conclusion The peltier-cooled provides an effective means of assaying cold sensitivity in unrestrained rats. Behavioral testing of cold allodynia, hyperalgesia and pain will greatly facilitate the study of the neurobiological mechanisms involved in cold/cool sensations and enable measurement of the efficacy of pharmacological treatments to reduce these symptoms.

Human Physiological Responses to Acute and Chronic Cold Exposure

Science.gov (United States)

Stocks, Jodie M.; Taylor, Nigel A. S.; Tipton, Michael J.; Greenleaf, John E.

2001-01-01

When inadequately protected humans are exposed to acute cold, excessive body heat is lost to the environment and unless heat production is increased and heat loss attenuated, body temperature will decrease. The primary physiological responses to counter the reduction in body temperature include marked cutaneous vasoconstriction and increased metabolism. These responses, and the hazards associated with such exposure, are mediated by a number of factors which contribute to heat production and loss. These include the severity and duration of the cold stimulus; exercise intensity; the magnitude of the metabolic response; and individual characteristics such as body composition, age, and gender. Chronic exposure to a cold environment, both natural and artificial, results in physiological alterations leading to adaptation. Three quite different, but not necessarily exclusive, patterns of human cold adaptation have been reported: metabolic, hypothermic, and insulative. Cold adaptation has also been associated with an habituation response, in which there is a desensitization, or damping, of the normal response to a cold stress. This review provides a comprehensive analysis of the human physiological and pathological responses to cold exposure. Particular attention is directed to the factors contributing to heat production and heat loss during acute cold stress, and the ability of humans to adapt to cold environments.

Equipment to weld fuel rods of mixed oxides

International Nuclear Information System (INIS)

Aparicio, G.; Orlando, O.S.; Olano, V.R.; Toubes, B.; Munoz, C.A.

1987-01-01

Two welding outfits system T1G were designed and constructed to weld fuel rods with mixed oxides pellets (uranium and plutonium). One of them is connected to a glove box where the loading of sheaths takes place. The sheaths are driven to the welder through a removable plug pusher in the welding chamber. This equipment was designed to perform welding tests changing the parameters (gas composition and pressure, welding current, electrode position, etc.). The components of the welder, such as plug holder, chamber closure and peripheral accessories, were designed and constructed taking into account the working pressures in the machine, which is placed in a controlled area and connected to a glove box, where special safety conditions are necessary. The equipment to weld fuel bars is complemented by another machine, located in cold area, of the type presently used in the fuel elements factory. This equipment has been designed to perform some welding operations in sheaths and mixed oxide rods of the type Atucha I and II. Both machines have a programmed power supply of wide range and a vacuum, and pressurizing system that allows the change of parameters. Both systems have special features of handling and operation. (Author)

Spent nuclear fuel project cold vacuum drying facility supporting data and calculation database

Energy Technology Data Exchange (ETDEWEB)

IRWIN, J.J.

1999-02-26

This document provides a database of supporting calculations for the Cold Vacuum Drying Facility (CVDF). The database was developed in conjunction with HNF-SD-SNF-SAR-002, ''Safety Analysis Report for the Cold Vacuum Drying Facility'', Phase 2, ''Supporting Installation of Processing Systems'' (Garvin 1998). The HNF-SD-SNF-DRD-002, 1997, ''Cold Vacuum Drying Facility Design Requirements'', Rev. 2, and the CVDF Summary Design Report. The database contains calculation report entries for all process, safety and facility systems in the CVDF, a general CVD operations sequence and the CVDF System Design Descriptions (SDDs). This database has been developed for the SNFP CVDF Engineering Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved.

Impact of burnable absorber Gd on nuclide composition for VVER-440 fuel (Gd-2)

International Nuclear Information System (INIS)

Zajac, R.; Chrapciak, V.

2010-01-01

The latest version of Russian fuel VVER-440 includes burnable absorber in 6 pins. In this article is impact of burnable absorber on nuclide composition and criticality analyzed. In part 1 was analyzed whole burnup interval 0-50 MWd/kgU. In present part 2 are detailed analysis only for first cycle (burnup 0-10 MWd/kgU). (Authors)

Performance enhancement of direct ethanol fuel cell using Nafion composites with high volume fraction of titania

Science.gov (United States)

Matos, B. R.; Isidoro, R. A.; Santiago, E. I.; Fonseca, F. C.

2014-12-01

The present study reports on the performance enhancement of direct ethanol fuel cell (DEFC) at 130 °C with Nafion-titania composite electrolytes prepared by sol-gel technique and containing high volume fractions of the ceramic phase. It is found that for high volume fractions of titania (>10 vol%) the ethanol uptake of composites is largely reduced while the proton conductivity at high-temperatures is weakly dependent on the titania content. Such tradeoff between alcohol uptake and conductivity resulted in a boost of DEFC performance at high temperatures using Nafion-titania composites with high fraction of the inorganic phase.

Fuel channel refilling

International Nuclear Information System (INIS)

Shoukri, M.; Abdul-Razzak, A.

1990-04-01

Analysis of existing data on fuel channel refilling is presented. The analysis focuses on the data obtained using the Stern Laboratories Cold Water Injection Test (CWIT) Facility. The two-fluid model thermal-hydraulics computer code CATHENA is also used to simulate experimental results on fuel channel refilling from both the CWIT and RD-14 facilities. Conclusions related to single and double break tests, including the effect of non-condensible gases, are presented. A set of recommendations is given for further analysis and separate effect experiments. (67 figs., 5 tabs., 24 refs.)

Fabrication and thermophysical property characterization of UN/U3Si2 composite fuel forms

Science.gov (United States)

White, J. T.; Travis, A. W.; Dunwoody, J. T.; Nelson, A. T.

2017-11-01

High uranium density composite fuels composed of UN and U3Si2 have been fabricated using a liquid phase sintering route at temperatures between 1873 K and 1973 K and spanning compositions of 10 vol% to 40 vol% U3Si2. Microstructural analysis and phase characterization revealed the formation of an U-Si-N phase of unknown structure. Microcracking was observed in the U-Si portion of the composite microstructure that likely originates from the mismatched coefficient of thermal expansion between the UN and U3Si2 leading to stresses on heating and cooling of the composite. Thermal expansion coefficient, thermal diffusivity, and thermal conductivity were characterized for each of the compositions as a function of temperature to 1673 K. Hysteresis is observed in the thermal diffusivity for the 20 vol% through 40 vol% specimens between room temperature and 1273 K, which is attributed to the microcracking in the U-Si phase. Thermal conductivity of the composites was modeled using the MOOSE framework based on the collected microstructure data. The impact of irradiation on thermal conductivity was also simulated for this class of composite materials.

Polybenzimidazole and sulfonated polyhedral oligosilsesquioxane composite membranes for high temperature polymer electrolyte membrane fuel cells

DEFF Research Database (Denmark)

Aili, David; Allward, Todd; Alfaro, Silvia Martinez

2014-01-01

Composite membranes based on poly(2,2′(m-phenylene)-5,5́bibenzimidazole) (PBI) and sulfonated polyhedral oligosilsesquioxane (S-POSS) with S-POSS contents of 5 and 10wt.% were prepared by solution casting as base materials for high temperature polymer electrolyte membrane fuel cells. With membranes...

Fuel poverty as a major determinant of perceived health: the case of France.

Science.gov (United States)

Lacroix, E; Chaton, C

2015-05-01

The number of households in fuel poverty is growing. Individuals increasingly struggle to heat their homes, and therefore, a growing number of individuals are exposed to low temperatures, which can affect their health. This study sought to determine the link between a subjective measure of fuel poverty (self-reported feeling cold) and self-reported health. The impact of other particular individual and environmental features on self-reported health were also analysed. Econometric analysis. The study method uses self-reported perception of thermal discomfort (self-reported feeling cold) as a proxy for fuel poverty. The French database of the Healthcare and Insurance survey carried by the Institute for Research and Information on Health Economics (IRDES) was used to estimate a dichotomous probit model. The estimation allows us to infer a negative impact of fuel poverty on self-reported health. Thus, a person in fuel poverty is 2.36 percentage points more likely to report poor or fair health status than a person who is not in fuel poverty. It may be appropriate to reduce the impacts of fuel poverty to provide support for the most vulnerable categories of individuals with respect to the health impacts of fuel poverty and cold homes, e.g., chronic patients who experience difficulty heating their homes. Copyright © 2015 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Mechanical and Microstructural Behavior of Cold-Sprayed Titanium- and Nickel-Based Coatings

Science.gov (United States)

Cavaliere, P.; Silvello, A.

2015-12-01

Cold spraying is a coating technology that can deposit materials with unique properties. The coating forms through intensive plastic deformation of particles impacting on a substrate at temperature well below the melting point of the sprayed material. Recently, various studies have been published regarding the microstructural and mechanical evolution of metal-matrix composite coatings produced by cold spraying. Herein, we describe the principal results of the available literature in the field of cold-sprayed composites. It is shown that more research is required to solve various questions in this field, for example, the different deformation modes of the material exhibited for various processing conditions, the reinforcing percentage of different material combinations, and the mechanical properties resulting from these complex systems. In the present study, this issue is approached and described for cold-sprayed Ni- and Ti-based composites. Materials were produced with varying ceramic phase (BN and TiAl3) fraction. The variation of the grain size, adhesion strength, porosity, and hardness of the deposits as a function of the ceramic phase fraction and processing parameters (impacting particle speed) is described. The interaction mechanisms between the cold-sprayed particles and the metal matrix during the coating process are presented and described. The results demonstrate a beneficial effect on grain size and porosity with increasing reinforcing phase percentage, as well as narrow processing parameter ranges to achieve the optimal properties with respect to the pure parent materials.

Fuel assembly

International Nuclear Information System (INIS)

Nakajima, Akiyoshi; Bessho, Yasunori; Aoyama, Motoo; Koyama, Jun-ichi; Hirakawa, Hiromasa; Yamashita, Jun-ichi; Hayashi, Tatsuo

1998-01-01

In a fuel assembly of a BWR type reactor in which a water rod of a large diameter is disposed at the central portion, the cross sectional area perpendicular to the axial direction comprises a region a of a fuel rod group facing to a wide gap water region to which a control rod is inserted, a region b of a fuel rod group disposed on the side of the wide gap water region other than the region a, a region d of a fuel rod group facing to a narrow gap water region and a region c of a fuel rod group disposed on the side of the narrow gap water region other than the region d. When comparing an amount of fission products contained in the four regions relative to that in the entire regions and average enrichment degrees of fuel rods for the four regions, the relative amount and the average enrichment degree of the fuel rod group of the region a is minimized, and the relative amount and the average enrichment degree of the fuel rod group in the region b is maximized. Then, reactor shut down margin during cold operation can be improved while flattening the power in the cross section perpendicular to the axial direction. (N.H.)

Study on the Influence of the Cold-End Cooling Water Thickness on the Generative Performance of TEG

Science.gov (United States)

Zhou, Li; Guo, Xuexun; Tan, Gangfeng; Ji, Kangping; Xiao, Longjie

2017-05-01

At present, about 40% of the fuel energy is discharged into air with the exhaust gas when an automobile is working, which is a big waste of energy. A thermoelectric generator (TEG) has the ability to harvest the waste heat energy in the exhaust gas. The traditional TEG cold-end is cooled by the engine cooling system, and although its structure is compact, the TEG weight and the space occupied are important factors restricting its application. In this paper, under the premise of ensuring the TEG maximum net output power and reducing the TEG water consumption as much as possible, the optimization of the TEG water thickness in the normal direction of the cold-end surface (WTNCS) is studied, which results in lighter weight, less space occupied and better automobile fuel economy. First, the thermal characteristics of the target diesel vehicle exhaust gas are evaluated based on the experimental data. Then, according to the thermoelectric generation model and the cold-end heat transfer model, the effect of the WTNCS on the cold-end temperature control stability and the system flow resistance are studied. The results show that the WTNCS influences the TEG cold-end temperature. When the engine works in a stable condition, the cold-end temperature decreases with the decrease of the WTNCS. The optimal value of the WTNCS is 0.02 m and the TEG water consumption is 8.8 L. Comparin it with the traditional vehicle exhaust TEG structure, the power generation increased slightly, but the water consumption decreased by about 39.5%, which can save fuel at0.18 L/h when the vehicle works at the speed of 60 km/h.

Highly Zeolite-Loaded Polyvinyl Alcohol Composite Membranes for Alkaline Fuel-Cell Electrolytes

Directory of Open Access Journals (Sweden)

Po-Ya Hsu

2018-01-01

Full Text Available Having a secure and stable energy supply is a top priority for the global community. Fuel-cell technology is recognized as a promising electrical energy generation system for the twenty-first century. Polyvinyl alcohol/zeolitic imidazolate framework-8 (PVA/ZIF-8 composite membranes were successfully prepared in this work from direct ZIF-8 suspension solution (0–45.4 wt % and PVA mixing to prevent filler aggregation for direct methanol alkaline fuel cells (DMAFCs. The ZIF-8 fillers were chosen for the appropriate cavity size as a screening aid to allow water and suppress methanol transport. Increased ionic conductivities and suppressed methanol permeabilities were achieved for the PVA/40.5% ZIF-8 composites, compared to other samples. A high power density of 173.2 mW cm−2 was achieved using a KOH-doped PVA/40.5% ZIF-8 membrane in a DMAFC at 60 °C with 1–2 mg cm−2 catalyst loads. As the filler content was raised beyond 45.4 wt %, adverse effects resulted and the DMAFC performance (144.9 mW cm−2 was not improved further. Therefore, the optimal ZIF-8 content was approximately 40.5 wt % in the polymeric matrix. The specific power output was higher (58 mW mg−1 than most membranes reported in the literature (3–18 mW mg−1.

Atmospheric pressure cold plasma treatment of cellulose based fillers for wood plastic composites

Science.gov (United States)

Lekobou, William; Englund, Karl; Pedrow, Patrick; Scudiero, Louis

2011-10-01

The main challenge of wood plastic composites (WPC) resides in the low interfacial adhesion due to incompatibility between the cellulose based filler that has a polar surface and most common matrixes, polyolefins which are non-polar. Plasma treatment is a promising technique for surface modification and its implementation into the processing of WPC would provide this industry with a versatile and nearly environmentally benign manufacturing tool. Our investigation aims at designing a cold atmospheric pressure plasma reactor for coating fillers with a hydrophobic material prior to compounding with the matrix. Deposition was achieved with our reactor that includes an array of high voltage needles, a grounded metal mesh, Ar as carrier gas and C2H2 as the precursor molecule. Parameters studied have included gas feed rates and applied voltage; FTIR, ESCA, AFM and SEM imaging were used for film diagnostics. We will also report on deposition rate and its dependence on radial and axial position as well as the effects of plasma-polymerized acetylene on the surface free energy of cellulose based substrates.

Nuclear reactor fuel assembly

International Nuclear Information System (INIS)

Sakurai, Shungo; Ogiya, Shunsuke.

1990-01-01

In a fuel assembly, if the entire fuels comprise mixed oxide fuels, reactivity change in cold temperature-power operation is increased to worsen the reactor shutdown margin. The reactor shutdown margin has been improved by increasing the burnable poison concentration thereby reducing the reactivity of the fuel assembly. However, since unburnt poisons are present at the completion of the reactor operation, the reactivity can not be utilized effectively to bring about economical disadvantage. In view of the above, the reactivity change between lower temperature-power operations is reduced by providing a non-boiling range with more than 9.1% of cross sectional area at the inside of a channel at the central portion of the fuel assembly. As a result, the amount of the unburnt burnable poisons is decreased, the economy of fuel assembly is improved and the reactor shutdown margin can be increase. (N.H.)

Proliferation resistance fuel cycle technology

Energy Technology Data Exchange (ETDEWEB)

Lee, J. S.; Ko, W. I

1999-02-01

The issues of dual use in nuclear technology are analysed for nuclear fuel cycle with special focus on uranium enrichment and spent fuel reprocessing which are considered as the most sensitive components in terms of vulnerability to diversion. Technical alternatives to mitigrate the vulnerability, as has been analysed in depth during the NASAP and INFCE era in the late seventies, are reviewed to characterize the DUPIC fuel cycle alternative. On the other hand, the new realities in nuclear energy including the disposition of weapon materials as a legacy of cold war are recast in an angle of nuclear proliferation resistance and safeguards with a discussion on the concept of spent fuel standard concept and its compliance with the DUPIC fuel cycle technology. (author)

Spent Nuclear Fuel Cold Vacuum Drying facility comprehensive formal design review report

International Nuclear Information System (INIS)

HALLER, C.S.

1999-01-01

The majority of the Cold Vacuum Drying Facility (CVDF) design and construction is complete; isolated portions are still in the design and fabrication process. The project commissioned a formal design review to verify the sufficiency and accuracy of current design media to assure that: (1) the design completely and accurately reflects design criteria, (2) design documents are consistent with one another, and (3) the design media accurately reflects the current design. This review is a key element in the design validation and verification activities required by SNF-4396, ''Design Verification and Validation Plan For The Cold Vacuum Drying Facility''. This report documents the results of the formal design review

Cold Vacuum Drying Instrument Air System Design Description. System 12

International Nuclear Information System (INIS)

SHAPLEY, B.J.; TRAN, Y.S.

2000-01-01

This system design description (SDD) addresses the instrument air (IA) system of the spent nuclear fuel (SNF). This IA system provides instrument quality air to the Cold Vacuum Drying (CVD) Facility. The IA system is a general service system that supports the operation of the heating, ventilation, and air conditioning (HVAC) system, the process equipment skids, and process instruments in the CVD Facility. The following discussion is limited to the compressor, dryer, piping, and valving that provide the IA as shown in Drawings H-1-82222, Cold Vacuum Drying Facility Mechanical Utilities Compressed and Instrument Air PandID, and H-1.82161, Cold Vacuum Drying Facility Process Equipment Skid PandID MCO/Cusk Interface. Figure 1-1 shows the physical location of the 1A system in the CVD Facility

Introducing the book 'Cold fusion and the future'

Energy Technology Data Exchange (ETDEWEB)

Rothwell, Jed

2006-07-01

Cold fusion will be the ideal source of energy, provided its introduction can be handled properly. A few cells have shown power density and temperatures suitable for real-world applications. Once these cells can be replicated on demand, commercial development will be straightforward. Manufacturing should not be too demanding, so thousands of companies will compete, and costs will fall quickly. The transition from fossil fuel to cold fusion will be rapid. Many extraordinary new applications will become possible, and seemingly intractable problems such as global warming may be fixed. Some examples will be presented. Public support is essential to funding research, and commercialization. 'Cold Fusion and the Future' is the title of a new book by this author. This paper discusses a few of the topics in the book.

Cold Vacuum Drying Instrument Air System Design Description (SYS 12)

Energy Technology Data Exchange (ETDEWEB)

SHAPLEY, B.J.; TRAN, Y.S.

2000-06-05

This system design description (SDD) addresses the instrument air (IA) system of the spent nuclear fuel (SNF). This IA system provides instrument quality air to the Cold Vacuum Drying (CVD) Facility. The IA system is a general service system that supports the operation of the heating, ventilation, and air conditioning (HVAC) system, the process equipment skids, and process instruments in the CVD Facility. The following discussion is limited to the compressor, dryer, piping, and valving that provide the IA as shown in Drawings H-1-82222, Cold Vacuum Drying Facility Mechanical Utilities Compressed & Instrument Air P&ID, and H-1.82161, Cold Vacuum Drying Facility Process Equipment Skid P&ID MCO/Cusk Interface. Figure 1-1 shows the physical location of the 1A system in the CVD Facility.

Bio composites from polypropylene/ clay/eva polymers and kenaf natural fiber

International Nuclear Information System (INIS)

Siti Hasnah Kamarudin; Khalina Abdan; Bernard Maringgal; Wan Mohd Zin Wan Yunus

2009-01-01

Full text: There is an increasing need to investigate more environmental friendly, sustainable materials to replace existing materials as industry attempts to lessen dependence on petroleum based fuels and products. The natural fiber composites offer specific properties comparable to those of conventional fiber composites. In this experiment, mixing process of polymer/nano clay composites from polypropylene, organo clay and ethylene vinyl acetate were prepared using a Brabender twin screw compounder. The composites sheets were then laminated with kenaf fibers and subjected to hot and cold press machine to form a bio composite. The mechanical properties such as flexural and impact strength are compare favourably between polymers reinforced kenaf fiber and polymers without kenaf fiber. In addition, various analysis techniques were used to characterize the dispersion and the properties of nano composites, using scanning electron micrograph (SEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). These results suggest that kenaf fibers are a viable alternative to inorganic mineral-based reinforcing fibers as long as the right processing conditions are used and they are used in applications where the higher water absorption is not critical. (author)

Cold Vacuum Drying Facility Design Basis Accident Analysis Documentation

International Nuclear Information System (INIS)

PIEPHO, M.G.

1999-01-01

This document provides the detailed accident analysis to support HNF-3553, Annex B, Spent Nuclear Fuel Project Final Safety Analysis Report, ''Cold Vacuum Drying Facility Final Safety Analysis Report (FSAR).'' All assumptions, parameters and models used to provide the analysis of the design basis accidents are documented to support the conclusions in the FSAR

The study of the peptide composition of the supernatants from mealworm Tenebrio molitor larvae and goldfish Carassius auratus during cold acclimation

Directory of Open Access Journals (Sweden)

А. К. Гулевский

2016-11-01

Full Text Available The molecular-mass distribution of peptides from supernatants, obtained from the tissues of larvae Tenebrio molitor and goldfish Carassius auratus during cold acclimation, has been determined by chromatography. The results showed that peptide spectrum of the supernatants from larvae T. molitor and C. auratus varied during cold acclimation. The supernatants from non-acclimated larvae of T. molitor and deacclimated fish possessed the highest number of peptide fractions. Furthermore, the cold-acclimated larvae of T. molitor had the peptide fractions of the low molecular weight (ca. 5.4×102 ÷22.6×102 Da, and non-acclimated insects had the peptides of the high molecular weight (ca. 46.8×102÷66×102 Da. Next, the organ-specific changes of the peptide composition of the goldfish during winter deacclimation have been revealed. Specifically, the low molecular weight peptides (ca. (14.1 ± 0.3×102 and (6.75 ± 0.25×102 Da, have been detected in the C. auratus muscles, and both the high (ca. (67.83 ± 0.21×102 ( ca. 64.16 ± 0.26×102 Da and low (ca. (34.1 ± 1.0×102 and (14.29 ± 0.15×102 Da molecular weight peptides have been detected in the liver. Quantitative and qualitative changes in the peptide spectra from supernatants of the T. molitor and C. auratus during cold acclimation could be one of the mechanisms of their natural adaptation to low temperatures.

Dimensional, microstructural and compositional stability of metal fuels

International Nuclear Information System (INIS)

Solomon, A.A.; Dayananda, M.A.

1993-01-01

The projects undertaken were to address two areas of concern for metal-fueled fast reactors: metallurgical compatibility of fuel and its fission products with the stainless steel cladding, and effects of porosity development in the fuel on fuel/cladding interactions and on sodium penetration in fuel. The following studies are reported on extensively in appendices: hot isostatic pressing of U-10Zr by coupled boundary diffusion/power law creep cavitation, liquid Na intrusion into porous U-10Zr fuel alloy by differential capillarity, interdiffusion between U-Zr fuel and selected Fe-Ni-Cr alloys, interdiffusion between U-Zr fuel vs selected cladding steels, and interdiffusion of Ce in Fe-base alloys with Ni or Cr

Chemical compositions, methods of making the chemical compositions, and structures made from the chemical compositions

Science.gov (United States)

Yang, Lei; Cheng, Zhe; Liu, Ze; Liu, Meilin

2015-01-13

Embodiments of the present disclosure include chemical compositions, structures, anodes, cathodes, electrolytes for solid oxide fuel cells, solid oxide fuel cells, fuel cells, fuel cell membranes, separation membranes, catalytic membranes, sensors, coatings for electrolytes, electrodes, membranes, and catalysts, and the like, are disclosed.

FY13 Summary Report on the Augmentation of the Spent Fuel Composition Dataset for Nuclear Forensics: SFCOMPO/NF

Energy Technology Data Exchange (ETDEWEB)

Brady Raap, Michaele C.; Lyons, Jennifer A.; Collins, Brian A.; Livingston, James V.

2014-03-31

This report documents the FY13 efforts to enhance a dataset of spent nuclear fuel isotopic composition data for use in developing intrinsic signatures for nuclear forensics. A review and collection of data from the open literature was performed in FY10. In FY11, the Spent Fuel COMPOsition (SFCOMPO) excel-based dataset for nuclear forensics (NF), SFCOMPO/NF was established and measured data for graphite production reactors, Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs) were added to the dataset and expanded to include a consistent set of data simulated by calculations. A test was performed to determine whether the SFCOMPO/NF dataset will be useful for the analysis and identification of reactor types from isotopic ratios observed in interdicted samples.

Development in the manufacture of fuel assembly components at Nuclear Fuel Complex

International Nuclear Information System (INIS)

Saibaba, N.

2012-01-01

The integrity of the fuel bundle and pellet-clad mechanical and chemical interaction (PCMCI) is the major limiting factor in achieving high burn up in thermal as well as fast reactors. Zircaloy based fuel bundle used for Indian pressurized heavy water reactor consists of number of components such as fuel clad tube, end cap bearing pad and spacer pad. These tubular, bar and sheet components are manufactured at Nuclear Fuel Complex using a series of thermomechanical processes involving hot and cold working with intermediate heat treatment. This paper is aimed at bringing out recent advances in NFC in the manufacture of fuel assembly components. Zircaloy based double clad tube adopting co-extrusion route followed by cold pilgering was successfully produced for its potential usage for high burnup in advance thermal reactors such as Advanced Heavy Water Reactors, This paper also includes process modifications carried out in the manufacture of clad tube and end cap components based on in-depth metallurgical studies. A radial forging process was established for primary breakdown of arc melted ingot which allows for better soundness and homogeneous microstructure. Manufacturing route of bar components for end caps was suitably modified by adopting only barrel straightening to minimize the residual stress and thereby increasing the recovery appreciably. NFC also supplies clad tube for fast breeder reactors where limiting factor for burn up are void swelling and fuel-clad interaction. In view of this, advance claddings such as P/M based 9Cr - Oxide Dispersion strengthened (ODS) steel clad and Zirconium lined T91 (9Cr-1 Mo) steel double clad have been successfully produced. Zirconium lined T91 (9Cr-1 Mo) double clad tubes required was successfully produced by adopting the method of co-pilgering, as a candidate material for clad tubes of Fast Breeder Reactors. (author)

Influence of driving cycles on Euro 3 scooter emissions and fuel consumption

International Nuclear Information System (INIS)

Prati, Maria V.; Zamboni, Giorgio; Costagliola, Maria A.; Meccariello, Giovanni; Carraro, Chiara; Capobianco, Massimo

2011-01-01

Highlights: → Fuel consumption and emissions of Euro 3 scooters defined on different driving cycles. → Comparison of standard, real world driving cycles and measured urban speed patterns. → Statistical analysis of kinematic parameters to group driving cycle in clusters. → Clusters can explain pollutant and fuel consumption behaviour in hot conditions. → Cold start mixture enrichment strategy has a major influence on extra-emissions. - Abstract: Regulated pollutant emissions and fuel consumption were characterized at the exhaust of two Euro 3 4-stroke medium-size motorcycles during the execution of both standard and real world driving cycles. A principal component analysis was carried out to group in a cluster the driving cycles with similar kinematic parameters. Hot start results, analysed according to this cluster grouping, show that the main differences are explained by overall mean speed and high positive acceleration of driving cycles. Lower mean speeds produce higher CO 2 emission factors, while the influence on CO and HC is more complex. NO X are not significantly affected by the driving pattern. Inside the same cluster, the whole duration of the acceleration phases could discriminate emission behaviour. In-depth analysis of cold start results was conducted in order to assess the influence of the driving cycle and vehicle characteristics on cold start duration. Cold start extra emissions are more influenced by the duration of the enrichment phase than by the catalyst light-off. The larger number of accelerations occurring during real world driving cycles produces higher variability of air fuel ratio and hence higher cold start extra emissions.

Development of a compound energy system for cold region houses using small-scale natural gas cogeneration and a gas hydrate battery

International Nuclear Information System (INIS)

Obara, Shin'ya; Kikuchi, Yoshinobu; Ishikawa, Kyosuke; Kawai, Masahito; Yoshiaki, Kashiwaya

2015-01-01

In this study, an independent energy system for houses in cold regions was developed using a small-scale natural gas CGS (cogeneration), air-source heat pump, heat storage tank, and GHB (gas hydrate battery). Heat sources for the GHB were the ambient air and geothermal resources of the cold region. The heat cycle of CO 2 hydrate as a source of energy was also experimentally investigated. To increase the formation speed of CO 2 hydrates, a ferrous oxide–graphite system catalyst was used. The ambient air of cold regions was used as a heat source for the formation process (electric charge) of the GHB, and the heat supplied by a geothermal heat exchanger was used for the dissociation process (electric discharge). Using a geothermal heat source, fuel consumption was halved because of an increased capacity for hydrate formation in the GHB, a shortening of the charging and discharging cycle, and a decrease in the freeze rate of hydrate formation space. Furthermore, when the GHB was introduced into a cold region house, the application rate of renewable energy was 47–71% in winter. The spread of the GHB can greatly reduce fossil fuel consumption and the associated greenhouse gases released from houses in cold regions. - Highlights: • Compound energy system for cold region houses by a gas hydrate battery was proposed. • Heat sources of a gas hydrate battery are exhaust heat of the CGS and geothermal. • Drastic reduction of the fossil fuel consumption in a cold region is realized

A comparison of cold flow properties of biodiesel produced from virgin and used frying oil

Energy Technology Data Exchange (ETDEWEB)

Al-Shanableh, Filiz [Food Engineering Department, Near East University (Cyprus); Evcil, Ali; Govsa, Cemal [Mechanical Engineering Department, Near East University (Cyprus); Savasdylmac, Mahmut A. [Mechanical Engineering Department, Booazici University (Turkey)

2011-07-01

Bio-diesel can be produced from different kinds of feedstock. The purpose of this paper is to research and make the comparison of the cold flow properties of bio-diesel produced from refined-virgin frying vegetable oil (RVFVO) and waste frying vegetable oil (WFVO). As is known, bio-diesel fuel will have higher cloud points (CP), cold filter plugging points (CFPP) and pour points (PP) if it is derived from fat or oil which consists of significant amounts of saturated fatty compounds. Both RVFVO and WFVO were derived from the same cafeteria on a Near East University campus and converted to biodiesel fuel through base catalyzed transesterification reaction. As the current results show, there is no considerable difference in cold flow properties of the bio-diesel produced from RVFVO and WFVO. So WFVO seems be better positioned to serve as raw material in biodiesel production because of its lower cost and its environmental benefits.

Cold episodes in the Peruvian Central Andes: Composites, Types, and their Impacts over South America (1958-2014)

Science.gov (United States)

Sulca, J. C.; Vuille, M. F.; Roundy, P. E.; Trasmonte, G.; Silva, Y.; Takahashi, K.

2015-12-01

The Mantaro basin (MB) is located in the central Peruvian Andes. Occasionally, cold episodes are observed during austral summer (January-March), that strongly damage crops. However, little is known about the causes and impacts of such cold episodes. The main goal of this study is thus to characterize cold episodes in the MB and assess their large-scale circulation and teleconnections over South America (SA) during austral summer. To identify cold events in the MB daily minimum temperature (Tmin) for the period 1958-2014 from Huayao station, located within the MB was used. A cold episode is defined when daily minimum temperature drops below its 10-percentile for at least one day. Additionally, to study the sensitivity between physical mechanisms associated with cold episodes and temperature, cold episodes are classified in three groups: Weak cold episodes (7.5 ≤ Tmin ≤ 10 percentile), strong cold episodes (Tmin ≤ 2.5 percentile), but excluding the 9 coldest events (Tmin ≤ 0 ͦ C), henceforth referred to as extraordinary cold episodes. Several gridded reanalysis were used to characterize the large-scale circulation, cloud cover and rainfall over SA associated with these events. Weak and strong cold episodes in the MB are mainly associated with a weakening of the Bolivian High-Nordeste Low system by tropical-extratropical interactions. Both types of cold episodes are associated with westerly wind anomalies at mid- and upper-tropospheric levels aloft the Peruvian Central Andes, which inhibit the influx of humid air masses from the lowlands to the east and hence limit the development of cloud cover (e.g., positive OLR anomalies over MB). The resulting clear sky conditions cause nighttime temperatures to drop, leading to cold extremes below 10-percentile. Simultaneously, northeastern Brazil (NEB) registers negative OLR anomalies, strong convection and enhanced cloud cover because displacement of the South Atlantic Convergence Zone (SACZ) toward the northeast of

Method and apparatus for real-time measurement of fuel gas compositions and heating values

Science.gov (United States)

Zelepouga, Serguei; Pratapas, John M.; Saveliev, Alexei V.; Jangale, Vilas V.

2016-03-22

An exemplary embodiment can be an apparatus for real-time, in situ measurement of gas compositions and heating values. The apparatus includes a near infrared sensor for measuring concentrations of hydrocarbons and carbon dioxide, a mid infrared sensor for measuring concentrations of carbon monoxide and a semiconductor based sensor for measuring concentrations of hydrogen gas. A data processor having a computer program for reducing the effects of cross-sensitivities of the sensors to components other than target components of the sensors is also included. Also provided are corresponding or associated methods for real-time, in situ determination of a composition and heating value of a fuel gas.

Effect of ethanol–gasoline blends on CO and HC emissions in last generation SI engines within the cold-start transient: An experimental investigation

International Nuclear Information System (INIS)

Iodice, Paolo; Senatore, Adolfo; Langella, Giuseppe; Amoresano, Amedeo

2016-01-01

Highlights: • This study assesses the effect of ethanol–gasoline blends on cold emissions. • A last generation motorcycle was operated on the chassis dynamometer. • A new calculation procedure was applied to model the cold transient behaviour. • The 20% v/v ethanol blend shows the highest reduction of CO and HC cold emissions. - Abstract: Urban areas in developed countries are characterized by an increasing decline in air quality state mainly due to the exhaust emissions from vehicles. Besides, due to catalyst improvements and electronic mixture control of last generation engines, nowadays CO and HC cold start extra-emissions are heavily higher than emissions exhausted in hot conditions, with a clear consequence on air quality of the urban contexts. Ethanol combined with gasoline can be widely used as an alternative fuel due to the benefit of its high octane number and its self-sustaining characteristics. Ethanol, in fact, is well known as potential alcohol alternative fuel for SI engines, since it can be blended with gasoline to increase oxygen content, then decreasing CO and HC emissions and the depletion of fossil fuels. Literature data about cold emissive behaviour of SI engines powered with ethanol/gasoline blended fuels are rather limited. For this reason, the aim of this study is to experimentally investigate the effect of ethanol/gasoline blends on CO and HC cold start emissions of four-stroke SI engines: a last generation motorcycle was operated on the chassis dynamometer for exhaust emission measurements without change to the engine design, while the ethanol was mixed with unleaded gasoline in different percentages (10, 20 and 30 vol.%). Results of the experimental tests and the application of a new calculation procedure, designed and optimised to model the cold transient behaviour of SI engines using different ethanol–gasoline blends, indicate that CO and HC cold start emissions decrease compared to the use of commercial gasoline, with the 20

Cold and hot model investigation of flow and mixing in a multi-jet flare

Energy Technology Data Exchange (ETDEWEB)

Pagot, P.R. [Petrobras Petroleo Brasileiro S.A., Rio de Janeiro (Brazil); Sobiesiak, A. [Windsor Univ., ON (Canada); Grandmaison, E.W. [Queen' s Univ., Kingston, ON (Canada). Centre for Advanced Gas Combustion Technology

2003-07-01

The oil and gas industry commonly disposes of hydrocarbon wastes by flaring. This study simulated several features of industrial offshore flares in a multi-jet burner. Cold and hot flow experiments were performed. Twenty-four nozzles mounted on radial arms originating from a central fuel plenum were used in the burner design. In an effort to improve the mixing and radiation characteristics of this type of burner, an examination of the effect of various mixing-altering devices on the nozzle exit ports was performed. Flow visualization studies of the cold and hot flow systems were presented, along with details concerning temperature, gas composition and radiation levels from the burner models. The complex flow pattern resulting when multiple jets are injected into a cross flow stream were demonstrated with the flow visualization studies from the cold model. The trajectory followed by the leading edge jet for the reference case and the ring attachments was higher but similar to the simple round jet in a cross flow. The precessing jets and the cone attachments were more strongly deflected by the cross flow with a higher degree of mixing between the jets in the nozzle region. For different firing rates, flow visualization, gas temperature, gas composition and radiative heat flux measurements were performed in the hot model studies. Flame trajectories, projected side view areas and volumes increased with firing rates for all nozzle configurations and the ring attachment flare had the smallest flame volume. The gas temperatures reached maximum values at close to 30 per cent of the flame length and the lowest gas temperature was observed for the flare model with precessing jets. For the reference case nozzle, nitrogen oxide (NOx) concentrations were in the 30 to 45 parts per million (ppm) range. The precessing jet model yielded NOx concentrations in the 22 to 24 ppm range, the lowest obtained. There was a linear dependence between the radiative heat flux from the flames

Size distribution, chemical composition and oxidation reactivity of particulate matter from gasoline direct injection (GDI) engine fueled with ethanol-gasoline fuel

International Nuclear Information System (INIS)

Luo, Yueqi; Zhu, Lei; Fang, Junhua; Zhuang, Zhuyue; Guan, Chun; Xia, Chen; Xie, Xiaomin; Huang, Zhen

2015-01-01

Ethanol-gasoline blended fuels have been widely applied in markets recently, as ethanol reduces life-cycle greenhouse gas emissions and improves anti-knock performance. However, its effects on particulate matter (PM) emissions from gasoline direct injection (GDI) engine still need further investigation. In this study, the effects of ethanol-gasoline blended fuels on particle size distributions, number concentrations, chemical composition and soot oxidation activity of GDI engine were investigated. It was found that ethanol-gasoline blended fuels increased the particle number concentration in low-load operating conditions. In higher load conditions, the ethanol-gasoline was effective for reducing the particle number concentration, indicating that the chemical benefits of ethanol become dominant, which could reduce soot precursors such as large n-alkanes and aromatics in gasoline. The volatile organic mass fraction in ethanol-gasoline particulates matter was higher than that in gasoline particulate matter because ethanol reduced the amount of soot precursors during combustion and thereby reduced the elemental carbon proportions in PM. Ethanol addition also increased the proportion of small particles, which confirmed the effects of ethanol on organic composition. Ethanol-gasoline reduced the concentrations of most PAH species, except those with small aromatic rings, e.g., naphthalene. Soot from ethanol-gasoline has lower activation energy of oxidation than that from gasoline. The results in this study indicate that ethanol-gasoline has positive effects on PM emissions control, as the soot oxidation activity is improved and the particle number concentrations are reduced at moderate and high engine loads. - Highlights: • Ethanol-gasoline reduces elemental carbon in PM. • Ethanol-gasoline increases volatile organic fraction in PM. • Soot generated from ethanol-gasoline has higher oxidation activity.

Fuel Class Higher Alcohols

KAUST Repository

Sarathy, Mani

2016-08-17

This chapter focuses on the production and combustion of alcohol fuels with four or more carbon atoms, which we classify as higher alcohols. It assesses the feasibility of utilizing various C4-C8 alcohols as fuels for internal combustion engines. Utilizing higher-molecular-weight alcohols as fuels requires careful analysis of their fuel properties. ASTM standards provide fuel property requirements for spark-ignition (SI) and compression-ignition (CI) engines such as the stability, lubricity, viscosity, and cold filter plugging point (CFPP) properties of blends of higher alcohols. Important combustion properties that are studied include laminar and turbulent flame speeds, flame blowout/extinction limits, ignition delay under various mixing conditions, and gas-phase and particulate emissions. The chapter focuses on the combustion of higher alcohols in reciprocating SI and CI engines and discusses higher alcohol performance in SI and CI engines. Finally, the chapter identifies the sources, production pathways, and technologies currently being pursued for production of some fuels, including n-butanol, iso-butanol, and n-octanol.

Sensitivity of dual fuel engine combustion and knocking limits to gaseous fuel composition

Energy Technology Data Exchange (ETDEWEB)

Selim, M.Y.E. [United Arab Emirates University, Al-Ain (United Arab Emirates). Dept. of Mechanical Engineering

2004-02-01

Combustion noise, knock and ignition limits data are measured and presented for a dual fuel engine running on dual fuels of Diesel and three gaseous fuels separately. The gaseous fuels used are liquefied petroleum gas, pure methane and compressed natural gas mixture. The maximum pressure rise rate during combustion is presented as a measure of combustion noise, and the knocking and ignition limits are presented as torque output at the onset of knocking and ignition failure. Experimental investigation on the dual fuel engine revealed the noise generated from combustion, knocking and ignition limits for all gases at different design and operating conditions. A Ricardo E6 Diesel version engine is converted to run on dual fuel of Diesel and the tested gaseous fuel and is used throughout the work. The engine is fully computerized, and the cylinder pressure data, crank angle data and engine operating variables are stored in a PC for off line analysis. The effects of engine speeds, loads, pilot injection angle, pilot fuel quantity and compression ratio on combustion noise, knocking torque, thermal efficiency and maximum pressure are examined for the dual engine running on the three gaseous fuels separately. The combustion noise, knocking and ignition limits are found to relate to the type of gaseous fuels and to the engine design and operating parameters. (author)

Sensitivity of dual fuel engine combustion and knocking limits to gaseous fuel composition

International Nuclear Information System (INIS)

Selim, Mohamed Y.E.

2004-01-01

Combustion noise, knock and ignition limits data are measured and presented for a dual fuel engine running on dual fuels of Diesel and three gaseous fuels separately. The gaseous fuels used are liquefied petroleum gas, pure methane and compressed natural gas mixture. The maximum pressure rise rate during combustion is presented as a measure of combustion noise, and the knocking and ignition limits are presented as torque output at the onset of knocking and ignition failure. Experimental investigation on the dual fuel engine revealed the noise generated from combustion, knocking and ignition limits for all gases at different design and operating conditions. A Ricardo E6 Diesel version engine is converted to run on dual fuel of Diesel and the tested gaseous fuel and is used throughout the work. The engine is fully computerized, and the cylinder pressure data, crank angle data and engine operating variables are stored in a PC for off line analysis. The effects of engine speeds, loads, pilot injection angle, pilot fuel quantity and compression ratio on combustion noise, knocking torque, thermal efficiency and maximum pressure are examined for the dual engine running on the three gaseous fuels separately. The combustion noise, knocking and ignition limits are found to relate to the type of gaseous fuels and to the engine design and operating parameters

Theoretical modeling of iodine value and saponification value of biodiesel fuels from their fatty acid composition

Energy Technology Data Exchange (ETDEWEB)

Gopinath, A.; Puhan, Sukumar; Nagarajan, G. [Internal Combustion Engineering Division, Department of Mechanical Engineering, Anna University, Chennai 600 025, Tamil Nadu (India)

2009-07-15

Biodiesel is an alternative fuel consisting of alkyl esters of fatty acids from vegetable oils or animal fats. The properties of biodiesel depend on the type of vegetable oil used for the transesterification process. The objective of the present work is to theoretically predict the iodine value and the saponification value of different biodiesels from their fatty acid methyl ester composition. The fatty acid ester compositions and the above values of different biodiesels were taken from the available published data. A multiple linear regression model was developed to predict the iodine value and saponification value of different biodiesels. The predicted results showed that the prediction errors were less than 3.4% compared to the available published data. The predicted values were also verified by substituting in the available published model which was developed to predict the higher heating values of biodiesel fuels from their iodine value and the saponification value. The resulting heating values of biodiesels were then compared with the published heating values and reported. (author)

Inorganic-based proton conductive composite membranes for elevated temperature and reduced relative humidity PEM fuel cells

Science.gov (United States)

Wang, Chunmei

Proton exchange membrane (PEM) fuel cells are regarded as highly promising energy conversion systems for future transportation and stationary power generation and have been under intensive investigations for the last decade. Unfortunately, cutting edge PEM fuel cell design and components still do not allow economically commercial implementation of this technology. The main obstacles are high cost of proton conductive membranes, low-proton conductivity at low relative humidity (RH), and dehydration and degradation of polymer membranes at high temperatures. The objective of this study was to develop a systematic approach to design a high proton conductive composite membrane that can provide a conductivity of approximately 100 mS cm-1 under hot and dry conditions (120°C and 50% RH). The approach was based on fundamental and experimental studies of the proton conductivity of inorganic additives and composite membranes. We synthesized and investigated a variety of organic-inorganic Nafion-based composite membranes. In particular, we analyzed their fundamental properties, which included thermal stability, morphology, the interaction between inorganic network and Nafion clusters, and the effect of inorganic phase on the membrane conductivity. A wide range of inorganic materials was studied in advance in order to select the proton conductive inorganic additives for composite membranes. We developed a conductivity measurement method, with which the proton conductivity characteristics of solid acid materials, zirconium phosphates, sulfated zirconia (S-ZrO2), phosphosilicate gels, and Santa Barbara Amorphous silica (SBA-15) were discussed in detail. Composite membranes containing Nafion and different amounts of functionalized inorganic additives (sulfated inorganics such as S-ZrO2, SBA-15, Mobil Composition of Matter MCM-41, and S-SiO2, and phosphonated inorganic P-SiO2) were synthesized with different methods. We incorporated inorganic particles within Nafion clusters

DUPIC fuel compatibility assessment

Energy Technology Data Exchange (ETDEWEB)

Choi, Hang Bok; Rho, G. H.; Park, J. W. [and others

2000-03-01

The purpose of this study is to assess the compatibility of DUPIC(Direct Use of Spent PWR Fuel in CANDU Reactors) fuel with the current CANDU 6 reactor, which is one of the technology being developed to utilize the spent PWR fuel in CANDU reactors. The phase 1 study of this project includes the feasibility analysis on applicability of the current core design method, the feasibility analysis on operation of the DUPIC fuel core, the compatibility analysis on individual reactor system, the sensitivity analysis on the fuel composition, and the economic analysis on DUPIC fuel cycle. The results of the validation calculations have confirmed that the current core analysis system is acceptable for the feasibility study of the DUPIC fuel compatibility analysis. The results of core simulations have shown that both natural uranium and DUPIC fuel cores are almost the same from the viewpoint of the operational performance. For individual reactor system including reactively devices, the functional requirements of each system are satisfied in general. However, because of the pronounced power flattening in the DUPIC core, the radiation damage on the critical components increases, which should be investigated more in the future. The DUPIC fuel composition heterogeneity dose not to impose any serious effect on the reactor operation if the fuel composition is adjusted. The economics analysis has been performed through conceptual design studies on the DUPIC fuel fabrication, fuel handling in a plant, and spent fuel disposal, which has shown that the DUPIC fuel cycle is comparable to the once-trough fuel cycle considering uncertainties associated with unit costs of the fuel cycle components. The results of Phase 1 study have shown that it is feasible to use the DUPIC fuel in CANDU reactors without major changes in hardware. However further studies are required to confirm the safety of the reactor under accident condition.

DUPIC fuel compatibility assessment

International Nuclear Information System (INIS)

Choi, Hang Bok; Rho, G. H.; Park, J. W. and others

2000-03-01

The purpose of this study is to assess the compatibility of DUPIC(Direct Use of Spent PWR Fuel in CANDU Reactors) fuel with the current CANDU 6 reactor, which is one of the technology being developed to utilize the spent PWR fuel in CANDU reactors. The phase 1 study of this project includes the feasibility analysis on applicability of the current core design method, the feasibility analysis on operation of the DUPIC fuel core, the compatibility analysis on individual reactor system, the sensitivity analysis on the fuel composition, and the economic analysis on DUPIC fuel cycle. The results of the validation calculations have confirmed that the current core analysis system is acceptable for the feasibility study of the DUPIC fuel compatibility analysis. The results of core simulations have shown that both natural uranium and DUPIC fuel cores are almost the same from the viewpoint of the operational performance. For individual reactor system including reactively devices, the functional requirements of each system are satisfied in general. However, because of the pronounced power flattening in the DUPIC core, the radiation damage on the critical components increases, which should be investigated more in the future. The DUPIC fuel composition heterogeneity dose not to impose any serious effect on the reactor operation if the fuel composition is adjusted. The economics analysis has been performed through conceptual design studies on the DUPIC fuel fabrication, fuel handling in a plant, and spent fuel disposal, which has shown that the DUPIC fuel cycle is comparable to the once-trough fuel cycle considering uncertainties associated with unit costs of the fuel cycle components. The results of Phase 1 study have shown that it is feasible to use the DUPIC fuel in CANDU reactors without major changes in hardware. However further studies are required to confirm the safety of the reactor under accident condition

Emergency fuels utilization guidebook. Alternative Fuels Utilization Program

Energy Technology Data Exchange (ETDEWEB)

1980-08-01

The basic concept of an emergency fuel is to safely and effectively use blends of specification fuels and hydrocarbon liquids which are free in the sense that they have been commandeered or volunteered from lower priority uses to provide critical transportation services for short-duration emergencies on the order of weeks, or perhaps months. A wide variety of liquid hydrocarbons not normally used as fuels for internal combustion engines have been categorized generically, including limited information on physical characteristics and chemical composition which might prove useful and instructive to fleet operators. Fuels covered are: gasoline and diesel fuel; alcohols; solvents; jet fuels; kerosene; heating oils; residual fuels; crude oils; vegetable oils; gaseous fuels.

Spent nuclear fuel project cold vacuum drying facility vacuum and purge system design description

Energy Technology Data Exchange (ETDEWEB)

IRWIN, J.J.

1998-11-30

This document provides the System Design Description (SDD) for the Cold Vacuum Drying Facility (CVDF) Vacuum and Purge System (VPS) . The SDD was developed in conjunction with HNF-SD-SNF-SAR-O02, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of Processing Systems (Garvin 1998), The HNF-SD-SNF-DRD-002, 1998, Cold Vacuum Drying Facility Design Requirements, and the CVDF Design Summary Report. The SDD contains general descriptions of the VPS equipment, the system functions, requirements and interfaces. The SDD provides references for design and fabrication details, operation sequences and maintenance. This SDD has been developed for the SNFP Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved.

Spent nuclear fuel project cold vacuum drying facility process water conditioning system design description

International Nuclear Information System (INIS)

IRWIN, J.J.

1998-01-01

This document provides the System Design Description (SDD) for the Cold Vacuum Drying Facility (CVDF) Process Water Conditioning (PWC) System. The SDD was developed in conjunction with HNF-SD-SNF-SAR-002, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of Processing Systems (Garvin 1998), the HNF-SD-SNF-DRD-O02, 1998, Cold Vacuum Drying Facility Design Requirements, and the CVDF Design Summary Report. The SDD contains general descriptions of the PWC equipment, the system functions, requirements and interfaces. The SDD provides references for design and fabrication details, operation sequences and maintenance. This SDD has been developed for the SNFP Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved

Spent nuclear fuel project cold vacuum drying facility vacuum and purge system design description

International Nuclear Information System (INIS)

IRWIN, J.J.

1998-01-01

This document provides the System Design Description (SDD) for the Cold Vacuum Drying Facility (CVDF) Vacuum and Purge System (VPS) . The SDD was developed in conjunction with HNF-SD-SNF-SAR-O02, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of Processing Systems (Garvin 1998), The HNF-SD-SNF-DRD-002, 1998, Cold Vacuum Drying Facility Design Requirements, and the CVDF Design Summary Report. The SDD contains general descriptions of the VPS equipment, the system functions, requirements and interfaces. The SDD provides references for design and fabrication details, operation sequences and maintenance. This SDD has been developed for the SNFP Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved

Processing of FRG mixed oxide fuel elements at General Atomic under the US/FRG cooperative agreement for spent fuel elements

International Nuclear Information System (INIS)

Holder, N.D.; Strand, J.B.; Schwarz, F.A.; Tischer, H.E.

1980-11-01

The Federal Republic of Germany (FRG) and the United States (US) are cooperating on certain aspects gas-cooled reactor technology under an umbrella agreement. Under the spent fuel treatment section of the agreement, FRG fuel spheres were recently sent for processing in the Department of Energy sponsored cold pilot plant for High-Temperature Gas-Cooled Reactor (HTGR) fuel processing at General Atomic Company in San Diego, California. The FRG fuel spheres were crushed and burned to recover coated fuel particles. These particles were in turn crushed and burned to recover the fuel-bearing kernels for further treatment for uranium recovery. Successful completion of the tests described in this paper demonstrated the applicability of the US HTGR fuel treatment flowsheet to FRG fuel processing. 10 figures

Spent nuclear fuel project cold vacuum drying facility safety equipment list

International Nuclear Information System (INIS)

IRWIN, J.J.

1999-01-01

This document provides the safety equipment list (SEL) for the Cold Vacuum Drying Facility (CVDF). The SEL was prepared in accordance with the procedure for safety structures, systems, and components (SSCs) in HNF-PRO-516, ''Safety Structures, Systems, and Components,'' Revision 0 and HNF-PRO-097, Engineering Design and Evaluation, Revision 0. The SEL was developed in conjunction with HNF-SO-SNF-SAR-O02, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of Processing Systems (Garvin 1998). The SEL identifies the SSCs and their safety functions, the design basis accidents for which they are required to perform, the design criteria, codes and standards, and quality assurance requirements that are required for establishing the safety design basis of the SSCs. This SEL has been developed for the CVDF Phase 2 Safety Analysis Report (SAR) and shall be updated, expanded, and revised in accordance with future phases of the CVDF SAR until the CVDF final SAR is approved

Convectively-driven cold layer and its influences on moisture in the UTLS

Science.gov (United States)

Kim, J.; Randel, W. J.; Birner, T.

2016-12-01

Characteristics of the cold anomaly in the tropical tropopause layer (TTL) that is commonly observed with deep convection are examined using CloudSat and Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) GPS radio occultation measurements. Deep convection is sampled based on the cloud top height (>17 km) from CloudSat 2B-CLDCLASS, and then temperature profiles from COSMIC are composited around the deep convection. The composite temperature shows anomalously warm troposphere (up to 14 km) and a significantly cold layer near the tropopause (at 16-18 km) in the regions of deep convection. Generally in the tropics, the cold layer has very large horizontal scale (2,000 - 6,000 km) compared to that of mesoscale convective cluster, and it lasts one or two weeks with minimum temperature anomaly of - 2K. The cold layer shows slight but clear eastward-tilted vertical structure in the deep tropics indicating a large-scale Kelvin wave response. Further analyses on circulation patterns suggest that the anomaly can be explained as a part of Gill-type response in the TTL to deep convective heating in the troposphere. Response of moisture to the cold layer is also examined in the upper troposphere and lower stratosphere using microwave limb sounder (MLS) measurements. The water vapor anomalies show coherent structures with the temperature and circulation anomalies. A clear dry anomaly is found in the cold layer and its outflow region, implying a large-scale dehydration process due to the convectively driven cold layer in the upper TTL.

Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems.

Science.gov (United States)

Rix, Laura; de Goeij, Jasper M; Mueller, Christina E; Struck, Ulrich; Middelburg, Jack J; van Duyl, Fleur C; Al-Horani, Fuad A; Wild, Christian; Naumann, Malik S; van Oevelen, Dick

2016-01-07

Shallow warm-water and deep-sea cold-water corals engineer the coral reef framework and fertilize reef communities by releasing coral mucus, a source of reef dissolved organic matter (DOM). By transforming DOM into particulate detritus, sponges play a key role in transferring the energy and nutrients in DOM to higher trophic levels on Caribbean reefs via the so-called sponge loop. Coral mucus may be a major DOM source for the sponge loop, but mucus uptake by sponges has not been demonstrated. Here we used laboratory stable isotope tracer experiments to show the transfer of coral mucus into the bulk tissue and phospholipid fatty acids of the warm-water sponge Mycale fistulifera and cold-water sponge Hymedesmia coriacea, demonstrating a direct trophic link between corals and reef sponges. Furthermore, 21-40% of the mucus carbon and 32-39% of the nitrogen assimilated by the sponges was subsequently released as detritus, confirming a sponge loop on Red Sea warm-water and north Atlantic cold-water coral reefs. The presence of a sponge loop in two vastly different reef environments suggests it is a ubiquitous feature of reef ecosystems contributing to the high biogeochemical cycling that may enable coral reefs to thrive in nutrient-limited (warm-water) and energy-limited (cold-water) environments.

Wear Behavior of Cold Pressed and Sintered Al2O3/TiC/CaF2Al2O3/TiC Laminated Ceramic Composite

Institute of Scientific and Technical Information of China (English)

Xuefeng YANG; Jian CHENG; Peilong SONG; Shouren WANG; Liying YANG; Yanjun WANG; Ken MAO

2013-01-01

A novel laminated Al2O3/TiC/CaF2-Al2O3/TiC sandwich ceramic composite was fabricated through cold pressing and sintering to achieve better anti-wear performance,such as low friction coefficient and low wear rate.Al2O3/TiC/CaF2 and Al2O3/TiC composites were alternatively built layer-by-layer to obtain a sandwich structure.Solid lubricant CaF2 was added evenly into the Al2O3/TiC/CaF2 layer to reduce the friction and wear.Al2O3/TiC ceramic was also cold pressed and sintered for comparison.Friction analysis of the two ceramics was then conducted via a wear-and-tear machine.Worn surface and surface compositions were examined by scanning electron microscopy and energy dispersion spectrum,respectively.Results showed that the laminated Al2O3/TiC/CaF2-Al2O3/TiC sandwich ceramic composite has lower friction coefficient and lower wear rate than those of Al2O3/TiC ceramic alone because of the addition of CaF2 into the laminated Al2O3/TiC/CaF2-Al2O3/TiC sandwich ceramic composite.Under the friction load,the tiny CaF2 particles were scraped from the Al2O3/TiC/CaF2 layer and spread on friction pairs before falling off into micropits.This process formed a smooth,self-lubricating film,which led to better anti-wear properties.Adhesive wear is the main wear mechanism of Al2O3/TiC/CaF2 layer and abrasive wear is the main wear mechanism of Al2O3/TiC layer.

Wear and Corrosion Properties of 316L-SiC Composite Coating Deposited by Cold Spray on Magnesium Alloy

Science.gov (United States)

Chen, Jie; Ma, Bing; Liu, Guang; Song, Hui; Wu, Jinming; Cui, Lang; Zheng, Ziyun

2017-08-01

In order to improve the wear and corrosion resistance of commonly used magnesium alloys, 316L stainless steel coating and 316L-SiC composite coating have been deposited directly on commercial AZ80 magnesium alloy using cold spraying technology (CS). The microstructure, hardness and bonding strength of as-sprayed coatings were studied. Their tribological properties sliding against Si3N4 and GCr15 steel under unlubricated conditions were evaluated by a ball-on-disk tribometer. Corrosion behaviors of coated samples were also evaluated and compared to that of uncoated magnesium alloy substrate in 3.5 wt.% NaCl solution by electrochemical measurements. Scanning electron microscopy was used to characterize the corresponding wear tracks and corroded surfaces to determine wear and corrosion mechanisms. The results showed that the as-sprayed coatings possessed higher microhardness and more excellent wear resistance than magnesium alloy substrate. Meanwhile, 316L and 316L-SiC coating also reduced the corrosion current density of magnesium alloy and the galvanic corrosion of the substrates was not observed after 200-h neutral salt spray exposure, which demonstrated that corrosion resistance of a magnesium alloy substrate could be greatly improved by cold-sprayed stainless steel-based coatings.

Alternative Sources of Energy - An Introduction to Fuel Cells

Science.gov (United States)

Merewether, E.A.

2003-01-01

Fuel cells are important future sources of electrical power and could contribute to a reduction in the amount of petroleum imported by the United States. They are electrochemical devices similar to a battery and consist of a container, an anode, a cathode, catalysts, an intervening electrolyte, and an attached electrical circuit. In most fuel cell systems, hydrogen is supplied to the anode and oxygen to the cathode which results in the production of electricity, water, and heat. Fuel cells are comparatively efficient and reliable, have no moving parts, operate without combustion, and are modular and scale-able. Their size and shape are flexible and adaptable. In operation, they are nearly silent, are relatively safe, and generally do not pollute the environment. During recent years, scientists and engineers have developed and refined technologies relevant to a variety of fuel cells. Types of fuel cells are commonly identified by the composition of their electrolyte, which could be either phosphoric acid, an alkaline solution, a molten carbonate, a solid metal oxide, or a solid polymer membrane. The electrolyte in stationary power plants could be phosphoric acid, molten carbonates, or solid metal oxides. For vehicles and smaller devices, the electrolyte could be an alkaline solution or a solid polymer membrane. For most fuel cell systems, the fuel is hydrogen, which can be extracted by several procedures from many hydrogen-bearing substances, including alcohols, natural gas (mainly methane), gasoline, and water. There are important and perhaps unresolved technical problems associated with using fuel cells to power vehicles. The catalysts required in several systems are expensive metals of the platinum group. Moreover, fuel cells can freeze and not work in cold weather and can be damaged by impacts. Storage tanks for the fuels, particularly hydrogen, must be safe, inexpensive, of a reasonable size, and contain a supply sufficient for a trip of several hundred miles

How cold is cold dark matter?

International Nuclear Information System (INIS)

Armendariz-Picon, Cristian; Neelakanta, Jayanth T.

2014-01-01

If cold dark matter consists of particles, these must be non-interacting and non-relativistic by definition. In most cold dark matter models however, dark matter particles inherit a non-vanishing velocity dispersion from interactions in the early universe, a velocity that redshifts with cosmic expansion but certainly remains non-zero. In this article, we place model-independent constraints on the dark matter temperature to mass ratio, whose square root determines the dark matter velocity dispersion. We only assume that dark matter particles decoupled kinetically while non-relativistic, when galactic scales had not entered the horizon yet, and that their momentum distribution has been Maxwellian since that time. Under these assumptions, using cosmic microwave background and matter power spectrum observations, we place upper limits on the temperature to mass ratio of cold dark matter today (away from collapsed structures). These limits imply that the present cold dark matter velocity dispersion has to be smaller than 54 m/s. Cold dark matter has to be quite cold, indeed

Advances in the manufacture of clad tubes and components for PHWR fuel bundle

International Nuclear Information System (INIS)

Saibaba, N.; Jha, S.K.; Chandrasekha, B.; Tonpe, S.; Jayaraj, R.N.

2010-01-01

Fuel bundles for Pressurized Heavy Water Reactors (PHWRs) consists of Uranium di-oxide pellets encapsulated into thin wall Zircaloy clad tubes. Other components such as end caps, bearing pads and spacer pads are the integral elements of the fuel bundle. As the fuel assembly is subjected to severe operating conditions of high temperature and pressure in addition to continual irradiation exposure, all the components are manufactured conforming to stringent specifications with respect to chemical composition, mechanical & metallurgical properties and dimensional tolerances. The integrity of each component is ensured by NDE at different stages of manufacture. The manufacturing route for fuel tubes and components comprise of a combination of thermomechanical processing and each process step has marked effect on the final properties. The fuel tubes are manufactured by processing the extruded blanks in four stage cold pilgering with intermediate annealing and final stress relieving operation. The bar material is produced by hot extrusion followed by multi-pass swaging and intermediate annealing. Spacer pads and bearing pads are manufactured by blanking and coining of Zircaloy sheet which is made by a combination of hot and cold rolling operations. Due to the small size and stringent dimensional requirements of these appendages, selection of production route and optimization of process parameters are important. This paper discusses about various measures taken for improving the recoveries and mechanical and corrosion properties of the tube, sheet and bar materials being manufactured at Nuclear Fuel Complex, Hyderabad For the production of clad tubes, modifications at extrusion stage to reduce the wall thickness variation, introduction of ultrasonic testing of extruded blanks, optimization of cold working and heat treatment parameters at various stages of production etc. were done. The finished bar material is subjected to 100% Ultrasonic and eddy current testing to ensure

Osmolality and composition of the extender during the cold storage of Prochilodus lineatus (Characiformes: Prochilodontidae sperm

Directory of Open Access Journals (Sweden)

Ana T. M. Viveiros

Full Text Available This study evaluates the effects of extender osmolality and composition on the cooling of Prochilodus lineatussperm. Sperm was diluted in six extenders: two compositions (powdered coconut water(tm = ACP; Beltsville Thawing Solution(tm = BTS x three osmolalities (285, 325, and 365 mOsm/kg plus an undiluted control, and stored at 6-8°C. Motility rate and velocities (curvilinear, straight line, and average path were determined every other day. Osmolality did not affect the quality of cooled sperm, thus data were pooled. Motility was higher on d 0 compared to the other days and diluted samples (85-90% yielded higher motility than control (75%. On d 2, motility was higher in BTS-diluted samples and control, but on d 4 and 6, control yielded the highest motility. Velocities decreased from d 0 to 6 in diluted samples, but not in control. On d 0, velocities were higher in BTS-diluted sperm, but, on d 2, 4, and 6, control yielded higher velocities despite of the large variation among males. Thus P. lineatussperm should be stored in BTS or without dilution, for a maximum of two days at 6-8°C. Extender osmolality between 285 and 365 mOsm/kg does not affect sperm quality during cold storage.

Sustainable Algae Biodiesel Production in Cold Climates

OpenAIRE

Baliga, Rudras; Powers, Susan E.

2010-01-01

This life cycle assessment aims to determine the most suitable operating conditions for algae biodiesel production in cold climates to minimize energy consumption and environmental impacts. Two hypothetical photobioreactor algae production and biodiesel plants located in Upstate New York (USA) are modeled. The photobioreactor is assumed to be housed within a greenhouse that is located adjacent to a fossil fuel or biomass power plant that can supply waste heat and flue gas containing CO2 as a ...

Cold Antimatter Plasmas, and Aspirations for Cold Antihydrogen

Science.gov (United States)

2002-06-24

UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP012494 TITLE: Cold Antimatter Plasmas, and Aspirations for Cold...part numbers comprise the compilation report: ADP012489 thru ADP012577 UNCLASSIFIED Cold Antimatter Plasmas, and Aspirations for Cold Antihydrogen G...and positrons. The antiprotons come initially from the new Antiproton Decel- erator facility at CERN. Good control of such cold antimatter plasmas is

Microstructure Evolution During Creep of Cold Worked Austenitic Stainless Steel

Science.gov (United States)

Krishan Yadav, Hari; Ballal, A. R.; Thawre, M. M.; Vijayanand, V. D.

2018-04-01

The 14Cr–15Ni austenitic stainless steel (SS) with additions of Ti, Si, and P has been developed for their superior creep strength and better resistance to void swelling during service as nuclear fuel clad and wrapper material. Cold working induces defects such as dislocations that interact with point defects generated by neutron irradiation and facilitates recombination to make the material more resistant to void swelling. In present investigation, creep properties of the SS in mill annealed condition (CW0) and 40 % cold worked (CW4) condition were studied. D9I stainless steel was solution treated at 1333 K for 30 minutes followed by cold rolling. Uniaxial creep tests were performed at 973 K for various stress levels ranging from 175-225 MPa. CW4 samples exhibited better creep resistance as compared to CW0 samples. During creep exposure, cold worked material exhibited phenomena of recovery and recrystallization wherein new strain free grains were observed with lesser dislocation network. In contrast CW0 samples showed no signs of recovery and recrystallization after creep exposure. Partial recrystallization on creep exposure led to higher drop in hardness in cold worked sample as compared to that in mill annealed sample. Accelerated precipitation of carbides at the grain boundaries was observed during creep exposure and this phenomenon was more pronounced in cold worked sample.

Impact of fuel composition on the recirculation zone structure and its role in lean premixed flame anchoring

KAUST Repository

Hong, Seunghyuck; Shanbhogue, Santosh J.; Ghoniem, Ahmed F.

2015-01-01

) and chemiluminescence measurements for C3H8/H2/air lean premixed flames stabilized in a backward-facing step combustor. Results show an intricate coupling between the flame anchoring and the RZ structure and length. For a fixed fuel composition, at relatively low

Performance of direct methanol fuel cell with a palladium–silica nanofibre/Nafion composite membrane

International Nuclear Information System (INIS)

Thiam, H.S.; Daud, W.R.W.; Kamarudin, S.K.; Mohamad, A.B.; Kadhum, A.A.H.; Loh, K.S.; Majlan, E.H.

2013-01-01

Highlights: • This study introduces Pd–SiO 2 Carbon Nano Fibre as an additive to Nafion membrane. • It investigates the effects of membrane annealing temperature and casting solvent. • Results show that Pd–SiO 2 fibre/Nafion performs lower methanol permeability. • This could effectively reduces methanol crossover in direct methanol fuel cell. - Abstract: Palladium–silica nanofibres (Pd–SiO 2 fibre) were adopted as an additive to Nafion recast membranes in order to reduce methanol crossover and improve the cell performance. The performance of a membrane electrode assembly (MEA) with fabricated composite membrane was evaluated through a passive air-breathing single cell direct methanol fuel cell (DMFC). The limiting crossover current density was measured to determine the methanol permeation in the DMFC. The effects of membrane annealing temperature and casting solvent of composite membrane on the cell performance were investigated and are discussed here. Compared to recast Nafion with the same thickness (150 μm), the Pd–SiO 2 fibre/Nafion composite membrane exhibited higher performance and lower methanol permeability. A maximum power density of 10.4 mW cm −2 was obtained with a 2 M methanol feed, outperforming the much thicker commercial Nafion 117 with a power density of 7.95 mW cm −2 under the same operating conditions. The experimental results showed that the Pd–SiO 2 fibre as inorganic fillers for Nafion could effectively reduce methanol crossover and improve the membrane performance in DMFC applications

Developing Spent Fuel Assembly for Advanced NDA Instrument Calibration - NGSI Spent Fuel Project

Energy Technology Data Exchange (ETDEWEB)

Hu, Jianwei [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gauld, Ian C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Banfield, James [GE Hitachi Nuclear Energy, Wilmington, NC (United States); Skutnik, Steven [Univ. of Tennessee, Knoxville, TN (United States)

2014-02-01

This report summarizes the work by Oak Ridge National Laboratory to investigate the application of modeling and simulation to support the performance assessment and calibration of the advanced nondestructive assay (NDA) instruments developed under the Next Generation Safeguards Initiative Spent Fuel (NGSI-SF) Project. Advanced NDA instrument calibration will likely require reference spent fuel assemblies with well-characterized nuclide compositions that can serve as working standards. Because no reference spent fuel standard currently exists, and the practical ability to obtain direct measurement of nuclide compositions using destructive assay (DA) measurements of an entire fuel assembly is prohibitive in the near term due to the complexity and cost of spent fuel experiments, modeling and simulation will be required to construct such reference fuel assemblies. These calculations will be used to support instrument field tests at the Swedish Interim Storage Facility (Clab) for Spent Nuclear Fuel.

Effect of aviation fuel type and fuel injection conditions on the spray characteristics of pressure swirl and hybrid air blast fuel injectors

Science.gov (United States)

Feddema, Rick

fuels. Optical patternation data and line of sight laser diffraction data show that there is significant difference between jet fuels. Particularly at low fuel injection pressures (0.345 MPa) and cold temperatures (-40 C), the patternation data shows that the total surface area in the spray at 38.1 mm from the pressure swirl injector for the JP-10 fuel type is one-sixth the amount of the JP-8. Finally, this study compares the atomizer performance of a pressure swirl nozzle to a hybrid air blast nozzle. The total surface area for both the hybrid air blast nozzle and the pressure swirl nozzle show a similar decline in atomization performance at low fuel injection pressures and cold temperatures. However, the optical patternator radial profile data and the line of sight laser diffraction data show that the droplet size and spray distribution data are less affected by injection conditions and fuel type in the hybrid air blast nozzle, than they are in the pressure swirl nozzle. One explanation is that the aerodynamic forces associated with the swirler on the hybrid air blast nozzle control the distribution droplets in the spray. This is in contrast to the pressure swirl nozzle droplet distribution that is controlled by internal geometry and droplet ballistics.

A Nafion-Ceria Composite Membrane Electrolyte for Reduced Methanol Crossover in Direct Methanol Fuel Cells

Directory of Open Access Journals (Sweden)

Parthiban Velayutham

2017-02-01

Full Text Available An alternative Nafion composite membrane was prepared by incorporating various loadings of CeO2 nanoparticles into the Nafion matrix and evaluated its potential application in direct methanol fuel cells (DMFCs. The effects of CeO2 in the Nafion matrix were systematically studied in terms of surface morphology, thermal and mechanical stability, proton conductivity and methanol permeability. The composite membrane with optimum filler content (1 wt. % CeO2 exhibits a proton conductivity of 176 mS·cm−1 at 70 °C, which is about 30% higher than that of the unmodified membrane. Moreover, all the composite membranes possess a much lower methanol crossover compared to pristine Nafion membrane. In a single cell DMFC test, MEA fabricated with the optimized composite membrane delivered a peak power density of 120 mW·cm−2 at 70 °C, which is about two times higher in comparison with the pristine Nafion membrane under identical operating conditions.

Cold Vacuum Drying (CVD) Facility Design Basis Accident Analysis Documentation

Energy Technology Data Exchange (ETDEWEB)

PIEPHO, M.G.

1999-10-20

This document provides the detailed accident analysis to support HNF-3553, Annex B, Spent Nuclear Fuel Project Final Safety Analysis Report, ''Cold Vacuum Drying Facility Final Safety Analysis Report (FSAR).'' All assumptions, parameters and models used to provide the analysis of the design basis accidents are documented to support the conclusions in the FSAR.

Development of a reference spent fuel library of 17x17 PWR fuel assemblies

International Nuclear Information System (INIS)

Rossa, Riccardo; Borella, Alessandro; Van der Meer, Klaas

2013-01-01

One of the most common ways to investigate new Non-Destructive Assays (NDA) for the spent fuel assemblies are Monte Carlo simulations. In order to build realistic models the user must define in an accurate way the material compositions and the source terms in the system. This information can be obtained using burnup codes such as ORIGEN-ARP and ALEPH2.2, developed at SCK-CEN. These software applications allow the user to select the irradiation history of the fuel assembly and to calculate the corresponding isotopic composition and neutron/gamma emissions as a function of time. In the framework of the development of an innovative NDA for spent fuel verifications, SCK•CEN built an extensive fuel library for 17x17 PWR assemblies, using both ORIGEN-ARP and ALEPH2.2. The parameters considered in the calculations were initial enrichment, discharge burnup, and cooling time. The combination of these variables allows to obtain more than 1500 test cases. Considering the broad range of the parameters, the fuel library can be used for other purposes apart from spent fuel verifications, for instance for the direct disposal in geological repositories. In addition to the isotopic composition of the spent fuel, the neutron and photon emissions were also calculated and compared between the two codes. The comparison of the isotopic composition showed a good agreement between the codes for most of the relevant isotopes in the spent fuel. However, specific isotopes as well as neutron and gamma spectra still need to be investigated in detail.

Hypothermic general cold adaptation induced by local cold acclimation.