Stalking the ultimate particle
If you missed the ARTE programme entitled "L'Ultime Particule" broadcast in February, you have another chance to catch it in CERN's Main Auditorium on 13 March. "L'Ultime Particule" is a documentary by the French director Michel Andrieu that seeks to explain particle physics through a contemplative quest for the research physicists of matter of today and yesteryear. Invariably kitted out in a red parka and a soft hat, the programme's investigator scours the planet and the archives in search of the research physicists who are stalking the ultimate particle, the Higgs boson, in their quest to understand the structure of matter. Naturally enough, CERN is an important stage of his journey where Michel Andrieu and his team spent several days last year. Both from the physics and metaphysical points of view, "L'Ultime Particule" is worth seeing. The film's director, Michel Andrieu, will introduce his documentary and answer ...
2003-01-01
Thursday 4 September From 14:00 to 17:00 - Training Centre Auditorium bldg. 593, room 11 The Summit Design VisualElite 4.0 Release Jean Marie St Paul / SUMMIT DESIGN, Europe, Technical Manager Michel Delcroix / SUMMIT DESIGN, Southern Europe, Sales F-95015 CERGY PONTOISE, France Summit Design is an important EDA digital hardware design tool supplier, and the industry leader in the emerging Electronic System Level design domain. Its VisualElite program has been used at CERN for several years. This seminar will include the highlights of the program's latest release. It will be illustrated how Summit Design products can provide a high-level C/C++ and SystemC functional modelling design and verification environment, enabling engineers to analyse system concepts before the implementation stage. The seminar will show how mixed SystemC and HDL simulation can be done, along with solutions for hardware/software development. HDL new ...
2003-01-01
CERN Academic Training Programme 2008/2009
LECTURE SERIES 8, 9, 10 11 & 12 June 2009 11:00-12:00 - Main Auditorium, Bldg. 500 Scenarios and Technological Challenges for a LHC Luminosity Upgrade: Introduction to the LHC Upgrade Program and Summary of Physics Motivations After a general introduction to the motivations for a LHC upgrade, the lectures will discuss the beam dynamics and technological challenges of the increase of the LHC luminosity, and the possible scenarios. Items such as a stronger final focus with larger aperture magnets, crab cavities, electron cloud issues, beam-beam interaction, machine protection and collimation will be discussed.Monday 8 June 2009 Introduction to the LHC upgrade program - L. Evans Summary of Physics Motivations - M. Mangano Tuesday 9 June 2009 The Dectector Upgrade and the Requirements on the Upgrade Scenarios - M. Nessi Wednesday 10 June 2009 Scenarios for the LHC Luminosity Upgrade - F. Zimmermann Thursday 11 June 2009 Main Accelerator Science Challenges: Magnet ...
2009-01-01
The Scientific Activities of CERN and Budget Estimates for the Years 1995-2005
The Scientific Activities of CERN and Budget Estimates for the Years 1995-2005
1993-01-01
To reduce the number of regular break-ins on CERN machines due to passwords exposed on the network in clear text, OFF-SITE FTP ACCESS TO CERN WILL BE BLOCKED in the CERN firewall from: Tuesday 20th January 2004 If you use ftp to access CERN computers from outside CERN then please see the link below for alternative access means and further advice: http://cern.ch/security/ftp Denise Heagerty, CERN Computer Security officer, Computer.Security@cern.ch
2004-01-01
To reduce the number of regular break-ins on CERN machines due to passwords exposed on the network in clear text, OFF-SITE FTP ACCESS TO CERN WILL BE BLOCKED in the CERN firewall from: Tuesday 20th January 2004 If you use ftp to access CERN computers from outside CERN then please see the link below for alternative access means and further advice: http://cern.ch/security/ftp Denise Heagerty, CERN Computer Security officer, Computer.Security@cern.ch
2003-01-01
The Large Hadron Collider and the Long-Term Scientific programme of CERN: Executive Summary
The Large Hadron Collider and the Long-Term Scientific programme of CERN: Executive Summary
1993-01-01
CERN se plantea adelantar asueto para reiniciar experimento en abril
CERN se plantea adelantar asueto para reiniciar experimento en abril
2008-01-01
Results of 3-dimensional structural FE-modeling of the coil end-regions of the LHC main dipoles
The transition region between the straight part and the ends of the coils of the LHC model and prototype dipole magnets are often identified as the origin of training quenches. In order to study how the discontinuities in the material properties of these regions affect coil pre-stress and possibly gain more insight in the quench behavior, a program was set up at CERN to analyze by 3D-FEM these particular regions. The ACCEL team, who performed a similar analysis for the main quadrupoles of the Superconducting Supercollider SSC, is entrusted with this program. In this paper we report on the results of 3D-modeling and analysis of the coil return end region, including the complete coil mass, of a 1-m single bore model magnet. This magnet represents all relevant features of the "two-in-one" LHC main dipole design concerning the winding configuration, the collar pack, the yoke, and the outer shell representing the He-vessel. The transition region ...
2000-01-01
Proposal for the award of a blanket purchase contract for the supply of electronics subracks for the CERN accelerator control system
2010-01-01
One of the many visiting theoricians R P Feynman who gave lectures at CERN during the year
One of the many visiting theoricians R P Feynman who gave lectures at CERN during the year
1970-01-01
CERN scientists confront data deluge
The next generation of particle accelerator is currently being designed at CERN. An understanding of the market forces in the computer industry will play a crucial role in the success of the project.
1998-01-01
A highly integrated trigger and readout system for a silicon micro-strip detector installed at the CERN Omega spectrometer
1991-01-01
48 CFR 552.211-87 - Export packing.
...furnished with commercial or military export packing. Military export packing, if offered, shall be in accordance with Mil-Std-2073-1 Level A or B as specified. If commercial export packing is offered, the offer or pricelist shall include...
2010-10-01
A last look at the green field, in the triangular wedge of land stray radiation near the CERN accelerators.
1965-01-01
International Science & Technology Center (ISTC)
Development of Scientific Foundations of the Technology of the Metal Matrix Packing of Leaky Unreprocessible Spent Nuclear Fuel of Different Purpose Reactors for a Long-term Environmentally Safe Storage.
University of Tennessee deploys force10 switch for CERN work
"Force20 networks, the pioneer in building and securing reliable networks, today announced that the University of Tennessee physics department has deployed the C300 resilient switch to analyze data form CERN's Large Hadron Collider." (1/2 page)
2007-01-01
Creating Open Digital Library Using XML Implementation of OAi-PMH Protocol at CERN
This article describes the implementation of the OAi-PMH protocol within the CERN Document Server (CDS). In terms of the protocol, CERN acts both as a data provider and service provider and the two core applications are described. The application of XML Schema and XSLT technology is emphasized.
2002-01-01
CHANGE@CERN:Changes in Industrial Services
The changes envisaged in the Management's draft plan will focus the resources of the Laboratory on the LHC project and its completion. One of CERN's largest areas of spending is in Industrial Service Contracts, which currently amount to nearly 15% of the CERN budget. At present more than 2000 people have access to CERN through such contracts, although the nature of the contracts means that expenditure is not only on labour but also on materials. The revised cost to completion of the LHC has caused understandable concern that savings in Industrial Services will give rise to job losses at CERN, and rumours of '500 lay-offs' appeared in some newspaper reports. These reports were based on misunderstanding and speculation rather than the actual plan being prepared at CERN. The current proposal regarding expenditure on Industrial Services - which is supported by the findings of Task Force ...
2002-01-01
Since the mid-1980s the number of scientists from all over the world using CERN's facilities has increased enormously. Currently more than 6,000 users, over half of the planet's high-energy physicists, carry out fundamental research at CERN. This user community is living proof that CERN welcomes inter- regional collaboration which benefits all and boosts the progress of science. The LHC, the only machine capable of addressing problems way beyond today's frontiers of high energy physics, offers an unique opportunity for extending world wide collaboration.
1994-01-01
Target stations and beam dumps for the CERN SPS
International Nuclear Information System (INIS)
The design of the absorber blocks for internal and external dumping of the SPS proton beam is discussed. In addition, the external target stations for slow and fast extracted proton beams are described.
1977-03-16
Effect of oxygen and oxidizing ions on denting corrosion
International Nuclear Information System (INIS)
Information is presented concerning solute concentration in a porous layer; solute concentration in a packed crevice; corrosion of a packed carbon steel crevice in NaCl-O"2 solutions; and effect of copper on corrosion in NaCl-O"2 solutions.
1983-01-01
300 W polymer electrolyte fuel cell generators for educational purposes
Energy Technology Data Exchange (ETDEWEB)
A 300 W fuel cell power pack has been developed for educational purposes in close collaboration with the Fachhochschule Solothurn Nordwestschweiz. The project was initiated and financed by the Swiss Federal Office of Energy. The outlay and the performance of the power pack are described. (author) 3 figs.
1999-08-01
Energy Technology Data Exchange (ETDEWEB)
As the amount of urban and industrial wastes is increasing more and more, recycling is very necessary. Daily, there are many news about packing, even more since European Union is getting ready a Directive that will propose and will impose the reuse and recycling of the materials used to produce the packs. This Directive will be followed by different national laws of the countries members of EU. This paper describes the increasing use of aluminium for packing, and particularly its use for beverage cans, its characteristic and applications.
1994-01-01
2.1.1 Levels of preservation and packaging and the levels of packing to be applied selectively are defined in MIL-STD-2073-1 and are mandatory for use or ...
Rising Total Hadron-Hadron Cross Sections
A historical summary is made on the measurements concerning the rising total hadron-hadron cross sections at high energies. The first part of this paper concerns the total cross section measurements performed at the Brookhaven, Serpukhov and Fermilab fixed target accelerators; then the measurements at the CERN Intersecting Storage Rings (ISR), and at the CERN and at the Tevatron Fermilab proton-antiproton colliders; finally the cosmic ray measurements at even higher energies. A short discussion on Conclusions and Perspectives follows.
2007-01-01
New Protocol is 50th anniversary gift to CERN
"Nine of CERN 's 20 Member States today a signed new Protocol on privileges and immunities. This brings the Organization into line with other European intergovernmental organizations, such as the European Space Agency and the European Southern Observatory, which already enjoy international status in all of their Member States" (2
2004-01-01
Are you interested in beam dynamics? Do you work on the LHC injectors or CLIC or maybe feasibility studies fornew machines? Then this is for youJAS'2000: Joint CERN-Japan-JINR-Russia-US SchoolFrontiers of Accelerator Technology: High Quality Beams to be held on a river boat between St. Petersburg and Moscow 1 to 14 July 2000. For further information see eitherhttp://schools.web.cern.ch/Schools/CAS/ orhttp://www.indiana.edu/~uspas/programs/js/jas2000.html
2000-01-01
China and CERN renew co-operation agreement for a further five years. During a visit to CERN on 17 February, Liu Yanhua, the vice-minister of science and technology of the People's Republic of China, signed a new co-operation agreement with the laboratory.
2004-01-01
Composite vector leptoquarks in e"+e-, #gamma#e, and #gamma##gamma# colliders
International Nuclear Information System (INIS)
We study the signals for composite vector leptoquarks in e"+e- colliders (CERN e"+e- collider LEP II, Next Linear Collider, and CERN Linear Collider) through their effects on the production of jet pairs, as well as their single and pair productions. We also analyze their production in #gamma#e and #gamma##gamma# collisions.
Energy Technology Data Exchange (ETDEWEB)
High energy physics is a basic research domain with a well established European and international cooperation. Cooperation can be of different type depending on the size of the facilities involved (accelerators), on their financing, and on the type of experiments that use these facilities. The CERN, the European center for nuclear research, created in October 1954, is the best example of such a cooperation. This article examines first the juridical and scientifical structure of the CERN and the mode of organization of big experiments. Then, it presents the role of international committees in the establishment of a common scientific policy in Europe and in the rest of the world. Finally, the possible future evolution of the CERN towards a worldwide project is evoked. (J.S.)
2004-07-01
Tubular packs Mo-AlN-Mo: long-term thermal and corrosion resistance
International Nuclear Information System (INIS)
Study results on long-term thermal and corrosion resistance of packs with electro-insulation layer of aluminium nitride are presented. Structural changes of nitride ceramics and contact zones between metal and ceramics are considered. It is shown that multilayer metallo-ceramic packs, manufactured by gas-phase technology have high electro- and thermophysical properties, high thermal and corrosion resistance relative to cesium vapor, vacuum density as well as high thermo-resistance. 8 refs., 4 figs.
Nitrogen oxides decreasing combustion method
Energy Technology Data Exchange (ETDEWEB)
A nitrogen oxides decreasing combustion method comprising: mixing a fuel and air with each other; bringing the mixture obtained into contact with a packed catalyst; and adding a fresh supply of the fuel to the stream obtained to form a mixed gas and causing the mixed gas to undergo non-catalytic thermal combustion, characterized in that only a catalytic reaction or combustion occurs at the packed catalyst; the temperature of the packed catalyst is kept lower than the ignition temperature of the mixture; the adiabatic flame temperature which is reached by the non-catalytic thermal combustion of the mixed gas is lower than the temperature at which the nitrogen oxides occur. 39 figs.
1988-10-19
and/or MIL-STD-2073-1 and MIL-STD-2073-2, as applicable, except as noted below: NONE. (b) The Contractor shall pack potentially hazardous items in ...
Energy Technology Data Exchange (ETDEWEB)
Ribbon parachute fabrics were tested during development and production of a 24 ft parachute, and after 2.5 years ambient exposure at several storage sites. The effects of sewing, packing, and parachute deployment on material strength were obtained in the 1000 lb Kevlar ribbon after moisture exposure during packing, and when packed parachutes absorbed moisture or were thermal cycled. Individual yarn samples from the low strength ribbons exhibited little change in strength indicating that the material itself had not degraded. Factors leading to the change in ribbon strength are discussed. Considering all materials, there have been no indications to date of any uncontrollable changes in material strength that would limit the use of Kevlar in parachute applications.
1984-01-01
D-11. The Contractor shall pack and mark all hardware deliverable under this ... Handling, and Transportation, and/or MIL-STD-2073-1 and MIL-STD 2073-2, ...
Influence of shape on ordering of granular systems in two dimensions
Energy Technology Data Exchange (ETDEWEB)
We investigate ordering properties of two-dimensional granular materials using several shapes created by welding ball bearings together. Ordered domains form much more easily in two than in three dimensions, even when configurations lack long-range order. The onset of ordered domains occurs near a packing density of 0.8, a phenomenon observed previously for disks. One of our shapes, the trapezoid, has packings that remain disordered and near the transition density even after annealing by shaking. Although random packings are unstable for disks and many other shapes in two dimensions, trapezoid packings provide an approach to studying two-dimensional randomness. We also find that the rotational symmetry of a shape is an excellent predictor of how easily it orders, and a potential guide to identifying two-dimensional shapes that remain random after annealing.
2001-06-01
Gun Shot Wound to the Chest of a Military Working Dog
... History of military working dogs: Pack dogs were in use by the military as far back as the Revolutionary War. World War ...
2009-06-01
UK PubMed Central (United Kingdom)
The oxygen production of a photosynthetic gas exchanger containing Chlorella pyrenoidosa (1% packed cell volume) was measured when various concentrations of carbon dioxide were present...Full Text Available
1967-05-01
Gadolinium electronic band structure: augmented plane wave calculation
International Nuclear Information System (INIS)
Augmented plane wave calculation of gadolinium electronic structure crystallized in a hexagonal close-packed lattice is carried out.
Purpose: The purpose of this study was to compare nutrient content and cost of home-packed lunches to nutrient standards and prices for reimbursable school lunches. Methods: Researchers observed food and beverage contents of 333 home packed lunches at four north Texas elementary schools. Nutritionist Pro was used to analyze lunches for calories, total fat, saturated fat, protein, fiber, vitamin A, vitamin C, calcium, iron, fiber, and sodium content. These values were then compared to National School Lunch Program (NSLP) standards and other nutrient standards. Cost of each home-packed lunch was estimated based on food prices at three local supermarkets. A one-sample t-test (p = 0.05) was used to compare nutrient values of home packed lunches to National School Lunch Program (NSLP) standards. A paired t-test was used to compare cost of home packed lunches to each school's full price ...
2008-12-01
Assessment of the Run to Detonation in Composition B from ...
... Thus initiation will be from the shock generated from the front surface of the pellet after traversing the inert packing. Exploding bridgewire detonator ...
1991-02-01
CERN signed a Co-operation Agreement with the Government of Pakistan in 1994, which was followed in 1997 by a Protocol signed with the Pakistan Atomic Energy Commission (PAEC) concerning CMS magnet supports. CERN and PAEC then signed in 1998 a Memorandum of Understanding for collaboration in the construction of the CMS detector. The participation by Pakistani scientists and engineers in the CERN programme is channelled through the National Centre of Physics (NCP) established at the Quaid-i-Azzam University in Islamabad, under the terms of a 1999 Protocol to the 1994 Co-operation Agreement. The engineering and detector construction work performed under these Agreements has been of high quality, and the Pakistani participation is valued highly by the CMS collaboration. In continuation of this co-operation, Pakistan, represented by PAEC as funding agency, has now proposed to make in-kind contributions to the LHC Project, such ...
2003-01-01
Inside the LEP control room at start-up
Physicists grouped around a screen in the LEP control room at the strat-up of LEP on 14 July 1989. The emotion of the moment is clear. Carlo Rubbia, Director-General of CERN at the time, is in the centre and on his left, Herwig Schopper, former Director-General of the Organization.
1989-01-01
Energy Technology Data Exchange (ETDEWEB)
CERN has encouraged the US-LARP collaboration to participate in Phase I of the LHC luminosity upgrade by analyzing the benefits gained by using Nb3Sn technology to replace the functionality of select NbTi magnets that CERN is committed to construct. Early studies have shown that the much higher gradients (shorter magnetic lengths) and temperature margins (quench stability) of Nb3Sn magnets compared to their NbTi counterparts is favorable--allowing the insertion of additional absorbers between Q1 and Q2, for example. This paper discusses the relative merits of the NbTi and Nb3Sn options.
2008-06-01
Forthcoming (n, #gamma#) measurements on the Fe and Ni isotopes at CERN n_TOF
International Nuclear Information System (INIS)
An overview of the past, present and future research activities at the CERN neutron time of flight facility n_TOF is given, with special focus on the astrophysical aspects. During the first campaign (Phase I), neutron capture cross sections of relevance for several aspects of the s-process nucleosynthesis have been measured. A second campaign has recently started (Phase II), aiming at the study of the weak s-process component via accurate (n,#gamma#) measurements of the Fe and Ni isotopes. Some changes in the facility will allow us to perform these measurements with improved experimental conditions.
2010-01-01
As an International Organization, one the most important issues that CERN has to respect and guarantee is the protection of the environment. Several of ST activities and operations have a direct impact on the environment: civil engineering works, electrical (transformers) and air-cooling operation, chemical products storage, various waste disposal etc.... Important measures, taken in the past, have to be kept and new ones should be applied in order to insure the conformity of the infrastructure with existing legislation, the correct operation of equipment and systems, the constant monitoring of the different situations and the traceability of the events. Moreover good management of the environment would bring large savings to CERN.
2003-01-01
Energy Technology Data Exchange (ETDEWEB)
Using the example of perhydrophenanthrene, perhydroanthracene and cyclopentanodecalin isomers a possibility is shown to use packed capillary columns containing graphitized thermal carbon black for a complete separation of high-boiling mixtures of polycyclic saturated hydrocarbon isomers in accordance with the geometric structure of their molecules.
1981-03-01
Heat exchange in a multi-cavity volumetric solar receiver
Energy Technology Data Exchange (ETDEWEB)
The concept of a multi-cavity volumetric solar receiver is very attractive for the profitability of certain of its characteristics such as high efficiency and economy. The absorber is based on a pack of small ceramic cavities which intercept and absorb the inherent high solar flux reflected from an array of mirrors. Atmospheric air acts as a coolant medium when it is drawn through the pack. A model for an overall heat transfer performance of the receiver is given and numerically solved.
1991-01-01
The present study numerically investigates the enhancement of forced convective heat transfer from a single circular cylinder embedded in a packed bed of spherical particles confined by two impermeable parallel plates. The heat transfer results from the heated cylinder, with and without the presence of a porous medium, are compared. The results show that the presence of the porous particles enhances the heat transfer from the cylinder; however, the significant heat transfer augmentation is produced at high Re due to the effect of thermal dispersion. In addition, the effect of Re on Nut is much greater than that of kr and Bi in the porous channel. It is also found that the %?p is much higher than %HTE producing from packing the empty channel.
2010-05-01
British Library Electronic Table of Contents (United Kingdom)
We aimed to investigate the effects of local anesthetics soaked in Merocel nasal packs on hemorrhage and pain after septoplasty. The methodology includes a prospective double-blind study that was conducted in patients undergoing septoplasty because of nasal septal deviation. The study included 143 patients. The patients were divided into four groups. Each group received 1% lidocaine?+?0.000625% adrenalin, 0.375% ropivacaine, 0.25% bupivacaine as study groups or 0.9% sodium chloride as a control group in their Merocel packs postoperatively. The local anesthetics or sodium chloride were reapplied at the eighth postoperative hour. Each patient was given a questionnaire where verbal analog score and amount of postoperative hemorrhage was noted. The statistical analysis was performed using two ...
2011-01-01
Le Club d’Orientation du CERN vous propose de venir participer à la cinquième étape de la coupe d’automne Genevoise. Celle-ci sera organisée samedi 16 octobre par le club de Lausanne-Jorat (Canton de Vaud). Un fléchage depuis le Mont-sur-Lausanne en direction de Cugy vous conduira au Chalet à Gobet. 5 circuits seront proposés sur la carte Le Flon. Les inscriptions et les départs se feront sur place de 13h à 15h. Il est prévu une initiation à 13h30 pour les débutants. Les deux dernières étapes de la coupe d’automne sont prévues pour vendredi 22 octobre au soir et samedi 23 octobre après-midi. Le Club d’Orientation du CERN Informations sur le site http://cern.ch/club-orientation
2010-01-01
A Versatile Evaporative Cooling System Designed for Use in an Elementary Particle Detector
British Library Electronic Table of Contents (United Kingdom)
An evaporative cooling system developed for operation and qualification testing of silicon pixel and microstrip detectors for the inner tracking detector of the CERN ATLAS spectrometer is described. Silicon detector substrates must be continuously operated between 0 and ???7?C in the high radiation environment near the circulating beams at the CERN Large Hadron Collider (LHC). This requirement imposes unusual constraints on the cooling system and has led to the choice of perfluoro-n-propane (C3F8) refrigerant, which combines good chemical stability under ionizing radiation with high dielectric strength and nonflammability. Since the silicon detectors must also be of extremely light construction to minimize undesirable physics background, coolant tubes are of thin (200 ?m) aluminum wall, wh...
2007-01-01
A Fast Ionization Chamber for Fission Cross-Section Measurements at n(_)TOF
International Nuclear Information System (INIS)
An ionization chamber with fast timing properties was built at CERN for measuring fission cross-sections of minor actinides at the n(_)TOF neutron beam. The design of this new chamber and of the front-end electronics was optimized to match the innovative features of the n(_)TOF facility, in particular the high instantaneous neutron flux and low background. For the most radioactive isotopes, a special version of the chamber, designed according to the ISO2919 standards, was built in order to comply with the radioprotection requirements at CERN. The detector and front-end electronics are here described, together with the simulated and measured response to fission fragments and #alpha#-particles. The performances of the chamber during the first measurement campaign at n(_)TOF are presented, focusing in particular on the fast time response, the good background rejection capability, low-background and high detection efficiency.
2008-09-01
Visiatome: The French Discovery and Information Center on Radioactive Waste Management
International Nuclear Information System (INIS)
The French radioactive waste management act of December 30, 1991, included two key provisions. It initiated a major research program with three areas of investigation concerning high-level long-lived radioactive waste management routes, and called for the Government to submit a legislative proposal to Parliament within 15 years (by 2006) specifying the policy guidelines adopted. Considering the sensitive nature of the subject, the questions surrounding the issue of radioactive waste, and the social, economic and environmental concerns for present and future generations, the Government has inaugurated, in 2005, a nationwide public debate on these issues between the submittal of the research reports and the parliamentary discussion of the proposed law. In this context, the CEA has decided to concentrate at Marcoule the expertise and experience acquired in the area of radioactive waste management and to make it available to stakeholders and to the public. A scientific cultural center, ...
Analysis of thermal comfort and indoor air quality in a mechanically ventilated theatre
Energy Technology Data Exchange (ETDEWEB)
Theatres are the most complex of all auditorium structures environmentally. They usually have high heat loads, which are of a transient nature as audiences come and go, and from lighting which changes from scene to scene, and they generally have full or nearly full occupancy. Theatres also need to perform well acoustically, both for the spoken word and for music, and as sound amplification is less used than in other auditoria, background noise control is critically important. All these factors place constraints on the ventilation design, and if this is poor, it can lead to the deterioration of indoor air quality and thermal comfort. To analyse the level of indoor air quality and thermal comfort in a typical medium-sized mechanically ventilated theatre, and to identify where improvements could typically be made, a comprehensive post-occupancy evaluation study was carried out on a theatre in Belgrade. The evaluation, based on the results of monitoring (temperature, ...
2008-07-01
Transitions between distinct compaction regimes in complexes of multivalent cationic lipids and DNA
We use X-ray scattering and molecular simulations to investigate the structural properties of complexes of multivalent cationic lipids and DNA molecules. At low mole fraction of neutral lipids (NLs), $\\Phi_{\\rm NL}$, the complexes show dramatic DNA compaction down to essentially close packed DNA arrays with a DNA interaxial spacing $d_{\\rm DNA}=25\\AA$. A gradual increase in $\\Phi_{\\rm NL}$ does not lead to a continuous increase in $d_{\\rm DNA}$ as observed for DNA complexes of monovalent cationic lipids (CLs). Instead, distinct spacing regimes exist, with sharp transitions between them. Three packing states have been identified: (i) close packed, (ii) condensed, but not close packed, with $d_{\\rm DNA}=27-28\\AA$, and (iii) an expanded state, where $d_{\\rm DNA}$ increases gradually with $\\Phi_{\\rm NL}$. Based on our experimental and computational results, we conclude that the DNA condensation ...
2008-01-01
Do calorie-controlled portion sizes of snacks reduce energy intake?
UK PubMed Central (United Kingdom)
In a cross-over study, participants (n=59) were randomly assigned to receive either 100 kcal packs or standard size packages of snacks for 1-week. After a minimum of a 1-week washout period,...Full Text Available
2009-06-01
Consideration of radiation effects in the choice of packaging materials
International Nuclear Information System (INIS)
Requirements for food packaging materials include whether there is any interaction between the food and the package during or after the irradiation, and whether as a result of the irradiation, volatile or leachable substances are released from the pack into the food. The performance of cellulose-based materials and plastic films under irradiation are discussed.
Coffee People Organic K-Cups for Keurig Brewers (Pack of 50): Amazon.com: Grocery & Gourmet Food
...options box during checkout as this item typically ships in its own packaging. 3 new from $29.95 Your Favorite Coffee, ...
Carbon dioxide absorption contactors: hollow fibre membranes and packed absorption columns
Energy Technology Data Exchange (ETDEWEB)
One of the important aspects in an absorption system is the effectiveness in which the gas and liquid phases come into contact with each other. An effective absorption process will provide sufficient contacting area for the gas and liquid phases to interact upon. With this in mind, work was conducted to evaluate carbon dioxide (CO{sub 2}) absorption into aqueous solutions of monoethanolamine (MEA) using two different types of contacting devices: gas absorption membrane (GAM) modules and traditional packed columns. The performance of these two absorption devices was compared to one another using the overall mass transfer coefficient (K{sub G}a{sub v}) as a basis. The GAM module contained microporous polypropylene hollow fibre membranes and the packed absorption column contained Sulzer DX structured packing. The results indicate that GAM modules tend to have slightly larger K{sub G}a{sub v} values, potentially opening the ...
2003-07-01
The effects of packaging materials on microbe population in irradiated traditional herbal medicines
International Nuclear Information System (INIS)
Microbial population and moisture content of traditional herbal medicines contaminated with 3 kinds of aerobic microbes, packed in 5 kinds of plastic packaging materials, followed by irradiation at minimum dose of 5 kGy and stored for 6 months were investigated. The highest reduction of microbial counts during storage was observed on samples packed in polyethylene bags. All of packaging materials used were found to be impermeable to microbes and water vapour. Radiation and packaging materials used acted synergistically to inactivate microbes durind storage. The microbial counts decreased as much as 2 to 4 log cycles during storage. (author).
With the help of self-assembly, thermal sintering, selective etching techniques and sol-gel process, the non-close packed (ncp) face-centered cubic (fcc) photonic crystals of titanium dioxide (TiO2) hollow spheres connected by TiO2 cylindrical tubes have been fabricated using silica template. The photonic bandgap calculations indicate that the ncp structure of TiO2 hollow spheres was easier to open the pseudogaps than close packed system at the lowest energy. PMID:17097102
2006-10-21
Nitrogen oxides decreasing combustion method
Energy Technology Data Exchange (ETDEWEB)
This patent describes a nitrogen oxides decreasing combustion method which comprises: a first step of mixing a fuel and air with each other; a second step of bringing the mixture obtained in the first step into contact with a packed catalyst such that only catalytic combustion occurs; and a third step of adding a fresh supply of the fuel to a stream obtained from the second step to form a mixed gas and causing the mixed gas to undergo non-catalytic thermal combustion. The temperature of the packed catalyst is lower than the ignition temperature of the mixture and the adiabatic flame temperature of the mixed gas is lower than a temperature at which the nitrogen oxides occur.
1988-03-22
Energy Technology Data Exchange (ETDEWEB)
Development of surface monitoring of the quality of round rubber packing rings for well instruments is discussed. A method is shown for testing the rings under conditions which simulate the operating conditions. A method is proposed for rapid monitoring of the conditions for vulcanization of the rings by the method of determining the ''ring modulus.''
1983-01-01
Basic radiation sterilization properties of packaging materials
International Nuclear Information System (INIS)
The foils of various materials were irradiated with "6"0Co with an activity of 11,538 TBq. The minimum radiation dose was 25 kGy. Changes in chemico-physical properties were evaluated by infrared spectroscopy and were not detected after irradiation with 25 kGy. Packing foils were subjected to the following tests: mechanical tests, tests of weld strength, tests of impact resistance, free fall tests, permeability tests for water vapour and microbiological tests. The results of all tests were tabulated. The tests showed that the foils are impermeable for microorganisms and provided the welds are airtight the packed products remain sterile. (J.P.).
1984-11-28
Research in experimental elementary particle physics. A proposal to the U.S. Department of Energy
Energy Technology Data Exchange (ETDEWEB)
We report on the activities of the High Energy Physics Group at the University of Texas at Arlington for the period 1994-95. We propose the continuation of the research program for 1996-98 with strong participation in the detector upgrade and physics analysis work for the D0 Experiment at Fermilab, prototyping and pre-production studies for the muon and calorimeter systems for the ATLAS Experiment at CERN, and detector development and simulation studies for the PP2PP Experiment at Brookhaven.
1995-04-13
Quench propagation in AFM Bi-2223 conductors for current lead applications
In this paper, the authors report on the electrical and thermal properties of Bi-2223 composite conductors prepared by the "accordion-folding method" (AFM). Thermal behavior study on AFM Bi-2223 conductors similar to those that have been successfully used to assemble the cold stage of low-loss current leads for CERN, has been performed by using a newly developed experimental apparatus that is described in detail. (7 refs).
2001-01-01
Nel tunnel alla ricerca di una nuova fisica
The Large Hadron Collider is at the top of world-wide science for particle physics. It promises to open the road to a new knowledge of the universe and its nature. Luciano Maiani and Robert Aymar, actual and future Director Generals of CERN, explain the aims of this most powerful instrument, the difficulties and the industrial repercussions, among which will be the "Grid", that will change the telecommunications (4 pages)
2003-01-01
IEEE 8023 ethernet, current status and future prospects at the LHC
The status of the IEEE 802.3 standard is reviewed and prospects for the future, including the new 10 Gigabit version of Ethernet, are discussed. The relevance of Ethernet for experiments at the CERN Large Hadron Collider is considered, with emphasis on on-line applications and areas which are technically challenging. 8 Refs.
2000-01-01
Evidence for long-lived isomeric states in neutron-deficient /sup 236/Am and /sup 236/Bk nuclei
Energy Technology Data Exchange (ETDEWEB)
A 5.76 MeV alpha-particle group has been observed in Am and Bk sources separated from a CERN W target. The data are interpreted due to the production of long-lived isomeric states in /sup 236/Am and /sup 236/Bk which decay to /sup 236/Pu. The possibility of high spin states as well as of shape isomeric states is raised.
1987-06-04
The internal-tracking-system (ITS) of the ALICE detector at LHC, consists of six concentrical barrels of silicon detectors. The outmost two layers are made of double-sided strip detectors (SSD). In the framework of a R and D, the characteristics and performances of these devices, manufactured by two different companies, associated with their designed read-out electronics, have been studied off- and in-beam at the SPS (CERN). The results are presented and discussed.
1999-01-01
A brief history of the World Wide Web Where it as invented, how it's used, and where it's headed
The World Wide Web has its historical roots in things such as the creation of the telegraph, the launching of the Sputnik and more, but it really all started in March 1989, when Tim Berners-Lee, a computer scientist at CERN in Geneva wrote a paper called Information Management: A proposal
2005-01-01
The performance tests used the water scrubber for ruthenium rejection
Energy Technology Data Exchange (ETDEWEB)
LEDF (Large Equipment Dismantling Facility) will be constructed for the purpose of decontaminating the high level {alpha} solid waste generated in oarai engineering center of JNC. And, main processing process of LEDF is incineration and melting system. LEDF will be intended to reduce the secondary waste that occurs along with the operation of the off gas processing equipment of incineration and melting system. It assumed that we are able to eliminate the adsorption tower using silica gel, if the decontamination factor to volatile ruthenium is able to expect in the packed scrubber that is established to remove harmful gas. Thereupon, we carried out this tests that eliminates the adsorption tower and reduces the secondary waste. The decontamination factor (DF) to the volatile ruthenium by the water scrubber is confirmed in the established institution which is in Tokai Works. However, decontamination factor differs and depends on the ruthenium concentration, harmful ...
2002-11-01
The performance tests used the water scrubber for ruthenium rejection
International Nuclear Information System (INIS)
LEDF (Large Equipment Dismantling Facility) will be constructed for the purpose of decontaminating the high level #alpha# solid waste generated in oarai engineering center of JNC. And, main processing process of LEDF is incineration and melting system. LEDF will be intended to reduce the secondary waste that occurs along with the operation of the off gas processing equipment of incineration and melting system. It assumed that we are able to eliminate the adsorption tower using silica gel, if the decontamination factor to volatile ruthenium is able to expect in the packed scrubber that is established to remove harmful gas. Thereupon, we carried out this tests that eliminates the adsorption tower and reduces the secondary waste. The decontamination factor (DF) to the volatile ruthenium by the water scrubber is confirmed in the established institution which is in Tokai Works. However, decontamination factor differs and depends on the ruthenium concentration, harmful ...
{sup 99m}Tc generator preparation using (n, {gamma}){sup 99}Mo produced ex-natural molybdenum
Energy Technology Data Exchange (ETDEWEB)
Theoretical assessment on the chromatographic {sup 99m}Tc generator preparation using (n, {gamma}) {sup 99}Mo produced ex-natural molybdenum was carried out. The relationship between the neutron flux for MoO{sub 3} target activation, Mo-content or Mo adsorption capacity of column packing material, {sup 99m}Tc pertechnetate concentration and/or {sup 99m}Tc radioactivity of eluate was established. The reasonably lower limit of neutron flux of reactor and Molybdenum content of column packing material were found out to estimate the production of portable chromatographic generators available for nuclear medicine application. The concentration of {sup 99m}Tc pertechnetate eluate of low {sup 99m}Tc concentration using the column elution technique was also evaluate theoretically and conducted successfully in practice. Three options of {sup 99m}Tc generator using Titanium-Molybdate, Zirconium-Molybdate and Zirconium Oxide as generator ...
2003-03-01
Method of unilateral relaxation of a stressed rock mass intended to protect development workings
Energy Technology Data Exchange (ETDEWEB)
Introduces three designs of development working protection recommended for immediate roof, basic roof and a coal seam of 1.5-2 m, 2.5-4 m and 0.7-1.1 m thickness respectively. The first design of roof control includes a dummy road with breaker props (cutting-off support) and pack, and reinforced concrete props. The second pattern comprises a breaking gate, two rows of cutting-off timber support, up to 10 m long pack and wood chocks. According to the third pattern a breaking road was executed 5.7-6 m away from the face end with breaker props at both its sides. Two rows of pack chocks were added to the dip. Advantages and drawbacks of the three patterns are pointed out. Stress distribution in rock is shown. Position of roof and support before and after roof settling is shown. The cost of the three methods is analyzed. Recommendations useful in application of the method are provided.
1991-06-01
Immobilization of stationary phases onto chromatographic supports by gamma radiation
International Nuclear Information System (INIS)
Cobalt-60 gamma radiation has been found to be an effective means of immobilizing stationary phases onto gas and liquid chromatographic supports. The ability of a phase to crosslink was determined to be highly dependent on its chemical structure. Gamma radiation was employed to immobilize Se-30, a methylsilicone, and 216 PS onto Chromosorb WHP for packed column chromatography. The resultant columns exhibited increased thermal stability and a high degree of efficiency. Several blended phases containing varying ratios of Se-30:216 PS were also immobilized onto chromatographic packings. This work was further extended to the immobilization of Se-30 and 216 PS onto fused silica capillaries via gamma radiation. Columns exhibited excellent efficiency and improved thermal stability. An investigation into the role of immobilization of polymeric phases for HPLC was undertaken. Results indicate that gamma radiation can immobilzied polyoctadecylsiloxane ...
Four materials, carbon felt cube (CFC), granular graphite (GG), granular activated carbon (GAC) and granular semicoke (GS) were tested as packed anodic materials to seek a potentially practical material for microbial fuel cells (MFCs). The microbial community and its correlation with the electricity generation performance of MFCs were explored. The maximum power density was found in GAC, followed by CFC, GG and GS. In GAC and CFC packed MFCs, Geobacter was the dominating genus, while Azospira was the most populous group in GG. Results further indicated that GAC was the most favorable for Geobacter adherence and growth, and the maximum power densities had positive correlation with the total biomass and the relative abundance of Geobacter, but without apparent correlation with the microbial diversity. Due to the low content of Geobacter in GS, power generated in this system may be attributed to other microorganisms such as Synergistes, ...
2011-09-20
International Nuclear Information System (INIS)
Available in abstract form only. Full text of publication follows: In this study. simulation of carbon dioxide absorption by Sodium Hydroxide solution in a packed bed has been investigated. At first, mass and energy balances were applied around a differential height of the bed. So, the governing equations were obtained. Surface renewal theory by Danckwerts was used to represent the mass transfer operation Finally, by changing the operating parameters like solvent temperature, inlet gas composition pressure and height of the bed, the effect of these parameters on the absorption and the composition of carbon dioxide in exit stream have been investigated. (authors)
2007-09-02
Radiation treatment of medical devices and packaging materials. Pt. 1
International Nuclear Information System (INIS)
The first part of the study contains a literature compilation of more than 50 original publications reporting the radiation induced effects in 17 different high polymer materials and glass which are relevant in the manufacturing of medical devices or packing materials. The results collected demonstrate that high energy radiation, i.e. gamma- or X-rays, causes various physical and chemical alterations in high polymer materials. A detailed summary and discussion of the results of the original publications is not included in the present report, it will be presented in the second part of the study. Furthermore, the second part of the study will refer to the aspect of wholesomeness of irradiated medical devices or packing materials in a more general manner of representation. (orig.).
Porous β-SiAlON Ceramic with Closed Packed Macropore
British Library Electronic Table of Contents (United Kingdom)
Porous ?-SiAlON ceramics are synthesized by reaction bonded method using hollow alumina spheres (HASs) as both sintering aids and pore-forming agents. Both micropores and macropores, which are constructured by SiAlON grains with different morphologies, are formed in the final SiAlON samples. The micropores are three-dimentional, and are built by equiaxial grains. While the hollow macropores, which have the similar morphology to hollow alumina sphere, are packed by elongated grains. In the sintering process, the solid dissolution process takes place, giving rise to the different alumina concentration of liquid phase, and thus resulting in the formation of two kinds of grains, the equiaxial grain and the elongated grain.
2011-01-01
International Nuclear Information System (INIS)
Joint FAO/IAEA/WHO Expert Committee approved the use of radiation treatment of foods. Nowadays food packaging are mostly made of plastics, natural or synthetic, therefore effect of irradiation on these materials is crucial for packing engineering for food irradiation technology. By selecting the right polymer materials for food packaging it can be ensured that the critical elements of material and product performance are not compromised. When packaging materials are in contact with food at the time of irradiation that regulatory approvals sometimes apply. The review of the R-and-D and technical papers regarding material selection, testing and approval is presented in the report. The most information come from the USA where this subject is well elaborated, the International Atomic Energy Agency (IAEA) reports are reviewed as well. The report can be useful for scientists and food irradiation plants operators. (author)
British Library Electronic Table of Contents (United Kingdom)
The large amount of plastic products presently produced necessitates recycling and reuse of these non-biodegradable materials. However, the degradation in the mechanical properties of products made from recycled plastic is a major drawback that limits their use. This study aims to improve the mechanical properties of products made from recycled plastic by utilizing the Taguchi optimization method, instead of coupling the products with additives. By adopting L9 Taguchi OA, products made from various compositions of virgin and recycled plastic are produced by injection moulding. Four controllable factors (i.e., melt temperature, packing pressure, injection time, and packing time), each at three levels, are tested to determine the optimal combination of factors and levels in the manufacturing...
2011-01-01
Fabrication of colloidal crystals on hydrophilic/hydrophobic surface by spin-coating
British Library Electronic Table of Contents (United Kingdom)
Herein, we demonstrate the structure of the PS colloidal crystals which were fabricated on the hydrophilic/hydrophobic Si wafers by a spin-coating technique. Monodisperse PS colloids are spin-coated onto self-assembled monolayers of 3-(aminopropyl)triethoxysilane and propyltrimethoxysilane coated Si wafers. PS spheres organized as ordered close-packed face-centered cubic structure with (111) planes on the hydrophilic surface while they gathered without the crystal structure on the hydrophobic surface. This paper also reports a simple and rapid method to fabricate the close-packed structure of hollow TiO2 spheres. The colloidal crystal of TiO2 hollow spheres was prepared using the PS sphere template on the hydrophobic surface. The mechanism for the growing multilayers of self-assembled PS p...
2011-01-01
Detrital processing in streams exposed to acidic precipitation in the Central Appalachian Mountains
International Nuclear Information System (INIS)
Continuing high rates of acidic deposition in the eastern United States may lead to long-term effects on stream communities, because sensitive catchments are continuing to lose anions and cations. A two-year study of the effects of pH and associated water chemistry variables on detrital processing in three streams with different bedrock geology in the Monongahela National Forest, West Virginia were investigated. Leaf pack processing rates and macroinvertebrate colonization and microbial biomass (ATP concentration) on the packs in the three stream were compared. It was found that macroinvertebrate and microbial communities differed both among streams that differed in their capacity to buffer the effects of acidic precipitation and among years in the same stream; these differences in biotic communities were not large enough to affect rates of leaf processing between the two years of the study, but they did significantly affect processing rates ...
The compact linear collider CLIC
A high luminosity (10e34 - 10e35 cm square/s) electron-positron Collider (CLIC) with a nominal centre-of-mass energy of 3 TeV has been under study for a number of years at CERN within an international collaboration of laboratories and institutes to provide the HEP community with a new accelerator-based facility for the post-LHC era. In order to achieve the very high design luminosity, very low emittance beams have to be produced and focused down to very small beam sizes at the interaction point. Beam acceleration using high frequency normal-conducting structures operating at high accelerating fields significantly reduces the length and, in consequence, the cost of the linac. The overall length of the 3 TeV collider is about 33 km. The goals of the CLIC scheme are ambitious, and require further R&D to demonstrate that they are indeed technically feasible. A new test facility is being built at CERN for this purpose with the aim to demonstrate ...
2004-01-01
Particle physics -- Future directions
Energy Technology Data Exchange (ETDEWEB)
Wonderful opportunities await particle physics over the next decade, with the coming of the Large Hadron Collider at CERN to explore the 1-TeV scale (extending efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry breaking) and many initiatives to develop our understanding of the problem of identity: what makes a neutrino a neutrino and a top quark a top quark. Here I have in mind the work of the B factories and the Tevatron collider on CP violation and the weak interactions of the b quark; the wonderfully sensitive experiments at Brookhaven, CERN, Fermilab, and Frascati on CP violation and rare decays of kaons; the prospect of definitive accelerator experiments on neutrino oscillations and the nature of the neutrinos; and a host of new experiments on the sensitivity frontier. We might even learn to read experiment for clues about the dimensionality of spacetime. If we are inventive enough, we may be able to follow this ...
2001-11-29
Message concerning Severe Acute Respiratory Syndrome ("SARS")
IMPORTANT REMINDER If you have just come back from one of the regions identified by the WHO as being infected with SARS, it is essential to monitor your state of health for ten days after your return. The syndrome manifests itself in the rapid onset of a high fever combined with respiratory problems (coughing, breathlessness, breathing difficulty). Should these signs appear, you must contact the CERN Medical Service as quickly as possible on number 73802 or 73186 during normal working hours, and the fire brigade at all other times on number 74444, indicating that you have just returned from one of the WHO-identified areas with recent local transmission.China: Beijing, Hong Kong (Special Administrative Region), Guangdong Province, Inner Mongolia, Shanxi Province, Tianjin ProvinceTaiwan:TaipeiMoreover, until further notice the CERN Management requests that all trips to these various regions of the world be reduced to a strict minimum and then ...
2003-01-01
We discuss the impact for light neutralinos in an effective Minimal Supersymmetric extension of the Standard Model of the recent results presented by the CMS and ATLAS Collaborations at the CERN Large Hadron Collider for a search of supersymmetry in proton-proton collisions at a center-of-mass energy of 7 TeV with an integrated luminosity of 35 inverse pb. We find that, in the specific case of light neutralinos, efficiencies for the specific signature searched by ATLAS (jets+missing transverse energy and an isolated lepton) imply a lower sensitivity compared to CMS (which searches for jets +missing transverse energy). Focusing on the CMS bound, if squark soft masses of the three families are assumed to be degenerate, the combination of the ensuing constraint on squark and gluino masses with the experimental limit on the b to s + gamma decay imply a lower bound on the neutralino mass that can reach the value of 11.9 GeV, depending on the gluino mass. On the other ...
2011-01-01
Development of large-capacity refrigeration at 1.8 K for the Large Hadron Collider at CERN
CERN, the European Laboratory for Particle Physics, is working towards the construction of the Large Hadron Collider (LHC), a high-energy, high-luminosity particle accelerator and collider [1] of 26.7 km circumference, due to start producing frontier physics, by bringing into collision intense proton and ion beams with centre-of-mass energies in the TeV-per-constituent range, at the beginning of the next century. The key technology for achieving this ambitious scientific goal at economically acceptable cost is the use of high-field superconducting magnets using Nb-Ti conductor operating in superfluid helium [2]. To maintain the some 25 km of bending and focusing magnets at their operating temperature of 1.9 K, the LHC cryogenic system will have to produce an unprecedented total refrigeration capacity of about 20 kW at 1.8 K, in eight cryogenic plants distributed around the machine circumference [3]. This has requested the undertaking of an industrial development ...
1996-01-01
Energy Technology Data Exchange (ETDEWEB)
ATLAS is one of the four experiments which will take place at the LHC, the CERN future protons collider. This accelerator, which should start in 2007, will allow to continue the studies carried out by its predecessors, as the standard model Higgs boson and new physics searches. The very high luminosity -10 fb{sup -1} during the first three functioning years, then 100 fb{sup -1}- and the 14 TeV in the frame center will ease these studies. The Centre de Physique des Particules de Marseille took part in the ATLAS collaboration, taking in charge half of the End-cap electromagnetic calorimeter modules construction. The description of this sub-detector and the construction steps, in particular the electrical tests which allow the stacking validation, are presented in this document. These tests results, obtained for the live first production modules, are analysed. The pre-series module (module 0) performances, obtained with beam tests performed at ...
2002-09-01
At the inauguration of the new CMS visitor centre. The CMS experiment inaugurated a new visitor centre at its Cessy site on 14 June. This will allow the thousands of people who come to CERN each year to follow the construction of one the Laboratory's flagship experiments first-hand. CERN receives over 20,000 visitors each year. Until recently, many of them were taken on a guided tour of one of the LEP experiments. With the closure of LEP, however, trips underground are no longer possible, and the Visits' Service has put in place a number of other itineraries (Bulletin 46/2000). Since the CMS detector will be almost entirely constructed in a surface hall, it is now taking a big share of the limelight. The CMS visitor centre has been built on a platform overlooking CMS construction. It contains a set of clear descriptive posters describing the experiment, along with a video projection showing animations and movies about CMS construction. In the ...
2001-01-01
Towards Antihydrogen Trapping and Spectroscopy at ALPHA
Spectroscopy of antihydrogen has the potential to yield high-precision tests of the CPT theorem and shed light on the matter-antimatter imbalance in the Universe. The ALPHA antihydrogen trap at CERN's Antiproton Decelerator aims to prepare a sample of antihydrogen atoms confined in an octupole-based Ioffe trap and to measure the frequency of several atomic transitions. We describe our techniques to directly measure the antiproton temperature and a new technique to cool them to below 10 K. We also show how our unique position-sensitive annihilation detector provides us with a highly sensitive method of identifying antiproton annihilations and effectively rejecting the cosmic-ray background.
2011-01-01
The HARP experiment first physics results
The HARP experiment at CERN is performing extensive measurements of hadron production cross sections and secondary particle yields, in the momentum range 1.5-15 GeV/c, over the full solid angle and using a large set of cryogenic and solid targets. First measurements of hadron production cross-sections in the forward region are reported using an aluminium target 5% of an interaction length thick and a proton beam of 12.9 GeV/c. A preliminary analysis in the large angle region of elastic scattering events produced with the cryogenic hydrogen target at 3 GeV/c beam momentum is also presented.
2005-01-01
The AMS-02 electromagnetic calorimeter
The Electromagnetic Calorimeter (ECAL) of the AMS-02 experiment is a lead-scintillating fibers sampling calorimeter characterized by high granularity that allows to image the longitudinal and lateral showers development, a key issue to provide high electron/hadron discrimination. The light collection system and the FE electronics are designed to let the calorimeter operate over a wide energy range from few GeV up to 1 TeV. A full-scale prototype of the e.m. calorimeter was tested at CERN in October 2001 using electrons and pions beams with energy ranging from 3 to 100 GeV. Effective sampling thickness, linearity and energy resolution were measured. (8 refs).
2002-01-01
Status and Challenges of the LHC Construction
The LHC is designed to provide proton beams of 7 TeV and nominal luminosity of 10**34 cm**-2s**-1. This objective is achieved at an affordable cost by pushing all major collider components to the limits of technology, by upgrading the existing CERN accelerators and infrastructure, and by involving the technical expertise, resources and dedication of accelerator laboratories world-wide. Following a decade of intensive R&D and technical validation of major collider systems, the LHC construction is now fully underway. Major industrial contracts have been awarded and are in execution for the procurement of the magnet, cryogenics and other systems. In this report, the status of the design and construction of the major LHC systems is presented.
2001-01-01
Simultaneous measurement of the neutron capture and fission yields of "2"3"3U
International Nuclear Information System (INIS)
We have measured the neutron capture and fission cross section of "2"3"3U at the neutron time-of-flight facility n-TOF at CERN in the energy range from 1 eV to 1 MeV with high accuracy by using a high performance 4#pi# BaF_2 Total Absorption Calorimeter (TAC) as a detection device. The method, based on the shape analysis of the TAC energy response, allowing to disentangle between #gamma#'s originating from fission and capture will be presented as well as the first very preliminary results. (authors)
2007-04-22
International Nuclear Information System (INIS)
The improved facilities of the ISOLDE isotopic separator on-line with the 600 MeV synchrocyclotron at CERN opened the possibility to reach nuclei very far from stability (as far as 22 neutrons deficient in the Cs region and 27 neutrons deficient in the Hg region). Simultaneously the development of on-line spectrometry allowed the study of nuclei with very short half-lives and low counting rates. Results recently obtained in the odd-A iridium region are presented after a short summary of recent on-line devices developments and results. (Auth.).
Progress in construction of the LHC
The Large Hadron Collider (LHC) project, approved by the CERN Council in December 1994, has now fully entered its construction phase, with the detailed technical definition of the major systems, and the adjudication of a number of large procurement contracts. We first recall the main features and characteristics of the LHC, report on the advances in definition of the layout and optics as well as on preparation of the injector complex, and review recent progress in the key technical systems of the main ring: magnets, cryogenics and vacuum, as well as civil construction, which has started following acceptance by authorities in the Host States.
1998-01-01
Proceedings of the impedance and bunch instability workshop
Energy Technology Data Exchange (ETDEWEB)
This report discusses the following topics: impedance and bunch lengthening; single bunch stability in the ESRF; a longitudinal mode-coupling instability model for bunch lengthening; high-frequency behavior of longitudinal coupling impedance; beam-induced energy spreads at beam-pipe transitions; on the calculation of wake functions using MAFIA-T3 code; preliminary measurements of the bunch length and the impedance of LEP; measurements and simulations of collective effects in the CERN SPS; bunch lengthening in the SLC damping rings; and status of impedance measurements for the spring-8 storage ring.
1990-04-01
Inspire is the project name of a new High Energy Physics information system which will integrate present databases and repositories to host the entire corpus of the HEP literature and become the reference HEP scientific information platform worldwide. It is a common project between CERN, DESY, FERMILAB and SLAC. It will empower scientists with new tools to discover and access the results most relevant to their research; enable novel text- and data-mining applications; deploy new metrics to assess the impact of articles and authors. In addition, it will introduce the Web2.0 paradigm of user-enriched content in the domain of sciences with community-based approaches to the peer-review process.
2008-01-01
INSPIRE - The Next-Generation HEP Information System
CERN, DESY, Fermilab and SLAC have joined forces to build INSPIRE, the next-generation HEP information platform offering innovative tools for information discovery and communication. Representing a natural community-based evolution of SPIRES, INSPIRE provides fast access to the entire body of HEP literature. As a subject repository it will host fulltexts of preprints, Open Access journal articles and supplementary material like conference slides and multimedia, enabling novel text- and data mining applications. In the spirit of Web2.0 INSPIRE will also supply tools for collaboration and user-enriched content.
2010-01-01
Hyperfine structure studies with the COMPLIS facility
International Nuclear Information System (INIS)
COMPLIS is an experimental facility designed to carry out spectroscopic studies on radioisotopes produced by disintegration of elements available at CERN's Booster-ISOLDE on-line isotope separator. During recent series of experimental runs, hyperfine structure measurements have yielded information on nuclear moments and deformations of platinum and iridium isotopes. For the first time, population by #alpha#-decay from Hg was exploited to investigate "1"7"8"-"1"8"1Pt--the most neutron-deficient Pt isotopes yet studied. Successful measurements have recently been carried out on "1"8"2"-"1"8"9Ir.
1998-12-16
High power evaluation of X-band high power loads
Several types of X-band high power loads developed for several tens of MW range were designed, fabricated and used for high power tests at X-band facility of KEK. Some of them have been used for many years and few units showed possible deterioration of RF performance. Recently revised-design loads were made by CERN and the high power evaluation was performed at KEK. In this paper, the main requirements are recalled, together with the design features. The high power test results are analysed and presented
2010-01-01
H.S.H. Prince Radu of Hohenzollern-Veringen, Special Representative of the Romanian Government for Integration, Co-operation and Sustainable Development, is seen here visiting Microcosm, CERN's on-site exhibition centre. Photo 01: H.S.H. Prince Radu of Hohenzollern-Veringen (right) with his personal adviser Cornel Comsa inside Microcosm's full-scale model of a six-metre section of the LHC. Photos 04-06: H.S.H. Prince Radu of Hohenzollern-Veringen with Emma Sanders from ETT Division.
2002-01-01
Finite element stress analysis of the CMS magnet coil
The Compact Muon Solenoid (CMS) is one of the experiments which are being designed in the framework of the Large Hadron Collider (LHC) project at CERN. The design field of the CMS magnet is 4 T, the magnetic length is 12.38 m and the aperture is 6.36 m. This is achieved with a 4 layer-5 module superconducting Al-stabilized coil energised at a nominal current of 20 kA. The finite element analysis (FEA) carried out is axisymmetric elasto-plastic. FEA has also been carried out on the suspension system and on the conductor. (8 refs).
2000-01-01
No magnetic monopoles were found in 2.5*10/sup 18/ primary proton- aluminium interactions produced by exposing an aluminium target to the Fermilab 300 GeV/c proton beam. Negative searches have also resulted from exposures of material to electrons at SLAC and from pp interactions at the CERN-ISR. The monopole pair production probability in proton-nucleon collisions is shown to be of order 10/sup -18/ or less, with 95% confidence level, if monopoles have masses less than 12 GeV. (24 refs).
1975-01-01
$B \\to X_{s} \\gamma$ and $B \\to X_{s} l^{+} l^{-}$ decays at LHCb
\\lhcb is one of the four major experiments at the Large Hadron Collider (\\lhc) at CERN. It is custom built to look for CP violation and New Physics in rare decays of heavy flavour hadrons, like the B and D systems. Rare decays that occur via loop diagrams provide a way to probe New Physics at energy scales much higher than can be probed by direct production in experiments. In this article, the \\lhcb prospects for such measurements with exclusive decays of the type $B \\to \\Xs \\gamma$ and $B \\to X_{s} l^{+} l^{-}$ are presented.
2011-01-01
$B \\to X_s\\gamma$ and $B\\to X_sl^+l^-$ decays at LHCb
LHC$b$ is one the four major experiments at the Large Hadron Collider (LHC) at CERN. It is custom built to look for CP violation and New Physics in rare decays of heavy flavor hadrons, like the B and D systems. Rare decays that occur via loop diagrams provide a way to probe New Physics at energy scales much higher than can be probed by direct production in experiment. In this article, the LHC$b$ prospects for such measurement with exclusive decays of the type $B \\to X_s\\gamma$ and $B\\to X_sl^+l^-$ are presented.
2011-01-01
Results for the structural properties of random heaps of hard disks
Energy Technology Data Exchange (ETDEWEB)
The average angle of repose and the packing density of random planar heaps of hard disks falling ballistically onto a sticky base line, where the first layer of disks is quenched in random positions, are computed for heaps with a small fixed number of gaps in the base layer. The results we find appear to be almost independent of the size of the heap and they agree with those obtained from computer simulations of large systems.
1995-01-01
Energy Technology Data Exchange (ETDEWEB)
This book includes the latest developments and covers pump performance, selection and operations, materials, seals and packings, effective fluid characteristics, filtration, piping systems, economics, valves, instrumentation, automatic controls, power transmission equipment, pump and pipeline heating, and more. An extensive data section contains formulas, charts, symbols, nomographs, and standard specification documents.
1984-01-01
Positron wave function in ReO_3 by the APW method
International Nuclear Information System (INIS)
The wavefunction of a positron in ReO is calculated using the augmented-plane-wave method. Due to the loosely-packed structure of ReO_3, the ground-state GAMMA_1 wavefunction exhibits a marked anisotropy particularly around the oxygen ions, and a large fraction of a positron is distributed in the interstitial region. Experimental results of the positron annihilation 2#gamma#-correlations and the positron annihilation rates in ReO_3 are discussed based on the positron wavefunction. (orig.).
UK PubMed Central (United Kingdom)
Phthalate esters (PE's) are plasticizers used to soften PVC-based medical devices. PE's are the most abundant man-made pollutants and increase the risk of developing an allergic respiratory disease...Full Text Available
2009-07-01
On new methods for standardization of samples in activation analysis of biological materials
International Nuclear Information System (INIS)
New standardization techniques of samples in multielement instrumental neutron-activation analysis (INAA) of biological materials (BM) are considered. New methodical developments of sample preparation techniques, BM tableting, creation of comparison standards and standardization of packing material are suggested. Correlated data on concentration of different elements in standard specimens-comparison standards are presented for mass INAA, that is: for phenol-formaldehyde resin-base and human blood-base synthetic standards. 7 refs.; 3 tabs.
1988-06-26
...Butley river and Ore estuary, Boyton Marshes attracts breeding wading birds in spring and ducks, geese and swans in winter. It's also ...The spectacular cliffs at Fowlsheugh are packed with 130,000 breeding seabirds in the spring and summer, including guillemots, razorbills and kittiwakes. Freiston ...for its breeding avocets and terns, which can be seen throughout the spring and summer. Access is by boat only and the trip ... During spring and autumn, it is an ideal place to see migrant wading birds, gulls and terns. Leighton Moss Leighton ...
Modelling and simulation of rate-based mechanistic model for CO{sub 2} capture
Energy Technology Data Exchange (ETDEWEB)
The electric power industry can use the carbon dioxide absorption process to capture carbon from high-volume flue gas. However, the current cost of the process is too high due to the approximation method used in process design. The absorption column is typically designed with parameters that are assumed to be constant over the whole length of the column, resulting in an oversized unit. This approximation method is no longer valid given new environmental and economic concerns. In order to develop an accurate column design for high-efficiency carbon dioxide (CO{sub 2}) capture, it is necessary to understand the phenomena taking place in the system. A mechanistic model is presented for a robust absorber design that takes into account mass-transfer and hydrodynamic behaviour within the CO{sub 2} absorption columns. The capture performance of a packed column under a wide range of design and operating conditions was determined using a model based on the kinetics and ...
2003-07-01
Investigation of carbon dioxide absorption by absorbents impregnated with alkanol amines
Energy Technology Data Exchange (ETDEWEB)
In studying the absorption of carbon dioxide by absorbents impregnated with alkanol amines, researchers used a laboratory-scale packed column to determine the overall gas-phase mass-transfer coefficients and enhancement factors. A model derived for the mechanism of the chemical reaction taking place in the interfacial layer accounts for the effect of the reaction upon the absorption rate better than other models.
1981-01-01
International Nuclear Information System (INIS)
The hard-sphere radial distribution functions, g_H_S(r/d,#eta#), for the face-centered cubic and hexagonal close-packed phases have been computed by the Monte Carlo method at nine values of the packing fraction, #eta#[=(#pi#/6)#rho#d"3], ranging from 4% below the melting density to 99% of the close-packed density. The Monte Carlo data are used to improve available analytic expressions for g_H_S(r/d,#eta#). By utilizing the new g_H_S(r/d,#eta#) in the Henderson and Grundke method [J. Chem. Phys. 63, 601 (1975)], we next derive an expression for y_H_S(r/d,#eta#) [=g_H_S(r/d)exp#left brace##beta#V_H_S(r)#right brace#] inside the hard-sphere diameter, d. These expressions are employed in a solid-state perturbation theory [J. Chem. Phys. 84, 4547 (1986)] to compute solid-state and melting properties of the Lennard-Jones and inverse-power potentials. Results are in close agreement with Monte Carlo and lattice-dynamics ...
1991-11-01
Energy Technology Data Exchange (ETDEWEB)
The use of aqueous methyldiethanolamine (MDEA) for selective removal of hydrogen sulfide from acid gas streams has been studied in a 2 inch column packed with 1/4 inch ceramic Intalox saddles. The column was operated in a counter-current, steady state fashion. The feed gas composition varied between 1 and 5 mole % hydrogen sulfide and between 0 and 50 mole % carbon dioxide. In order to assist the development of packed column absorption models, the rate at which pure carbon dioxide absorbs into 2 M MDEA was measured as a function of pressure, liquid flow rate and packed bed length. The importance of end effects was carefully evaluated. In addition, draining and tracer methods were used to estimate the amount of static holdup present in the column. Using classical draining methods, as much as 50 % of the total holdup was found to be static. However, according to the step decrease in tracer method, less than 5 % of the total ...
1988-01-01
In this paper, we evaluate the performance of the 1- and 5-site models of methane on the description of adsorption on graphite surfaces and in graphitic slit pores. These models have been known to perform well in the description of the fluid-phase behavior and vapor-liquid equilibria. Their performance in adsorption is evaluated in this work for nonporous graphitized thermal carbon black, and simulation results are compared with the experimental data of Avgul and Kiselev (Chemistry and Physics of Carbon; Dekker: New York, 1970; Vol. 6, p 1). On this nonporous surface, it is found that these models perform as well on isotherms at various temperatures as they do on the experimental isosteric heat for adsorption on a graphite surface. They are then tested for their performance in predicting the adsorption isotherms in graphitic slit pores, in which we would like to explore the effect of confinement on the molecule packing. Pore widths of 10 and 20 A are chosen in this ...
2005-10-20
De-entrainment of boron by evaporation
Energy Technology Data Exchange (ETDEWEB)
The purpose of this research was to investigate the de-entrainment of boron for evaporators used in nuclear power plants. The forced circulation and semi-continuous type evaporator was used in the experiment. Cyclone and glass-wool packed column which is supposed to provide good decontamination factor as well as easy maintenance, were selected as de-entrainment device to be used in the evaporation of radioactive liquid wastes. The de-entrainment device combined with cyclone and glass-wool column has shown overall DF more than 1000 for boron.
1986-12-01
Neutron cross-sections on minor actinides for next generation reactors: new data from n_TOF (CERN)
International Nuclear Information System (INIS)
Full text: Climatic problems associated to the greenhouse effect have recently stimulated a renewed interest in nuclear energy production, and triggered new studies aimed at developing future generation systems that would address current major safety, proliferation and waste concerns. In particular a possible solution to the waste problem could come from transmutation of the highly radiotoxic nuclear waste in Accelerator Driven Systems or in Generation-IV fast nuclear reactors. The design and operation of the new systems require accurate cross-section data on a large number of isotopes, in particular plutonium, minor actinides, long-lived fission fragments and structural materials. An important contribution to the field is being provided since a few years by a new time of-flight facility operative at CERN, n_TOF. The main features of the neutron beam, in particular the wide energy spectrum, ranging from thermal energy to hundreds of MeV, the very high instantaneous ...
2008-06-01
Year-1 (heavy-ion) physics with CMS at the LHC
International Nuclear Information System (INIS)
The plans for the CERN LHC heavy ion program in 2010 are for collisions of lead ions during the month of November at an energy about half of the final 5.5 TeV/nucleon. The advanced preparations are mostly for extrapolations of the measurements at the maximum energy previously available, Au + Au at 0.2 TeV/nucleon. Because of the large increase in energy, surprises can be expected. One new feature made possible by the increased energy and the excellent muon energy resolution of CMS will be the study of the yields of the excited states of the upsilon meson as a function of angle and centrality. Although the main emphasis will be on the QGP formed by the overlapping parts of the Pb ions, the spectator parts and the electromagnetic field outside of the ions, #gamma#-Pb and #gamma##gamma#, are also important.
2010-06-01
The {sup 234}U neutron capture cross section measurement at the n TOF facility
Energy Technology Data Exchange (ETDEWEB)
The neutron capture cross-section of {sup 234}U has been measured for energies from thermal up to the keV region in the neutron time-of-flight facility n-TOF, based on a spallation source located at CERN. A 4{pi} BaF{sub 2} array composed of 40 crystals, placed at a distance of 184.9 m from the neutron source, was employed as a total absorption calorimeter (TAC) for detection of the prompt {gamma}-ray cascade from capture events in the sample. This text describes the experimental setup, all necessary steps followed during the data analysis procedure. Results are presented in the form of R-matrix resonance parameters from fits with the SAMMY code and compared to the evaluated data of Endf in the relevant energy region, indicating the good performance of the n-TOF facility and the TAC. (authors)
2008-07-01
The Multipoles Factory An Element of the LHC Control
The measurements performed at CERN on prototypes and first pre-series main dipole magnets confirm the need of an active control of the Large Hadron Collider to compensate the dynamic field changes during the proton beam injection and acceleration. This control requires in turn an accurate forecast of the magnetic field in the accelerator. We plan to predict the field on the basis of two elements: theoretical field models tailored through the accumulated knowledge of the main magnets during series tests, and an on-line measurement system running on few reference magnets tracking the LHC current cycle. Data coming from this "Multipoles Factory" will result from the fusion of the two sources. Based on this system we foresee to deliver calibration information for pre-defined accelerator cycles as well as real time information for the active control. In this paper we report the conceptual design of the system, and we discuss the features and performance of the models ...
2002-01-01
State of the art in fine filament NbTi superconductors at IGC
International Nuclear Information System (INIS)
The proposed Superconducting Super Collider (SSC) in the US and plans for a Large Hadron Collider LHC at CERN are likely to require micron size filaments to reduce micron size filaments to reduce magnetization effects at the low injection fields envisioned. Superconductors of NbTi, designed to meet these requirements, are described. These conductors contain from 6000 to 36,613 filaments. Results are presented on NbTi conductors made by multiple extrusion techniques. Filament sizes of between 2.2 and 17 micron have been obtained. Current densities of between 2400 A/mm"2 and nearly 3400 A/mm"2 at 5 Tesla have been achieved. Metallurgical aspects of these conductors are presented using both optical and SEM views of conductor cross section and filament surface.
1986-05-12
Recent developments at ISOLTRAP towards a relative mass accuracy of exotic nuclei below $10^{-8}$
During the last two years, the performance of the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN (Geneva) has been considerably enhanced. Many technical improvements have been completed (i) to access nuclides that are produced in minute quantities of only 100 ions s/sup -1/, (ii) to increase the relative mass accuracy to 2003-01-01
R and D for the development of negative ion beams of halogens
Energy Technology Data Exchange (ETDEWEB)
Ion beams of halogens can be produced either positively or negatively charged, depending on the employed ion source. At CERN-ISOLDE, although positively charged fluorine and astatine can be obtained from a hot plasma ion source, they are often contaminated by isobars and molecular sidebands. This has generated a request from the scientific community for fluorine and astatine negative ion beams free of contaminants. The high selectivity ensured by the surface ionisation process also makes negative beams of chlorine, bromine and iodine highly attractive. However, the efficiency figures for negative surface ionisation of fluorine and astatine were lower than the ones from the hot plasma. Here we report our R and D on new surface ion sources suitable for the production of negative halogen beams.
2008-10-15
Progress Report Towards the ICANOE Detector
We present a proposal for a combined ICARUS & NOE general purpose detector, to be installed in Hall B of the Gran Sasso Laboratory.The main scientific goal is the one of elucidating in a comprehensive way the pattern of neutrino $9 masses and mixings, following both (1) the S-KAM results and (2) the predictions on atmospheric neutrinos of the large solution of the Solar Neutrinos deficit. To achieve these goals, the experimental method is based upon the $9 complementary and simultaneous detection of CERN beam (CNGS) and cosmic ray (CR) events. This is made possible because of the complete isotropy of the detection technique. For the currently allowed values of the S-KAM results, both $9 CNGS and cosmic ray data will give independent measurements and provide a precise $(sin^{2}2\\theta; \\Delta m^{2})$ determination rather than a wide band of allowed values. Since we can observe and unambiguously identify $9 $\
1999-01-01
Particle Flow at CMS and the ILC
This thesis describes hadron reconstruction at the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) at CERN, Geneva. The focus is on the particle flow reconstruction of these objects. This thesis revisits the subject of the CMS calorimeters' non-linear response to hadrons. Data from testbeam experiments conducted in 2006 & 2007 is compared with simulations and substantial differences are found. A particle flow calibration to correct the energy response of the testbeam data is evaluated. The reconstructed jet response is found to change by ~ 5% when a data-driven calibration is used in place of the calibration derived from simulation. Collision data taken at the early stage of CMS' commissioning is also presented. The hadron response in data is determined to be compatible with testbeam results presented in this thesis. This thesis also details the use of neural networks to improve the energy measurement of hadrons at CMS. The networks ...
2010-01-01
International Nuclear Information System (INIS)
The RD50 collaboration has been exploring the development of radiation hard semiconductor devices for very high-luminosity colliders since 2002. The target fluence to qualify detectors set by the anticipated dose for the innermost tracking layers of the future upgrade of the CERN large hadron collider (LHC) is 1016 1 MeV neutron equivalent (neq) cm-2. This is about an order of magnitude higher than the maximum dose for the most exposed silicon detectors in the current machine. RD50 investigates the radiation hardening of silicon sensors from many angles: improvement of the intrinsic tolerance of the substrate material, optimisation of the readout geometry and study of novel design of detectors. A review of some of the recent activities within RD50 is here presented.
2009-01-01
British Library Electronic Table of Contents (United Kingdom)
The RD50 collaboration has been exploring the development of radiation hard semiconductor devices for very high-luminosity colliders since 2002. The target fluence to qualify detectors set by the anticipated dose for the innermost tracking layers of the future upgrade of the CERN large hadron collider (LHC) is 1016 1MeV neutron equivalent (neq) cm-2. This is about an order of magnitude higher than the maximum dose for the most exposed silicon detectors in the current machine. RD50 investigates the radiation hardening of silicon sensors from many angles: improvement of the intrinsic tolerance of the substrate material, optimisation of the readout geometry and study of novel design of detectors. A review of some of the recent activities within RD50 is here presented.
2009-01-01
Neutron-induced fission cross-section of {sup 233}U in the energy range 0.5<E{sub n}< 20 MeV
Energy Technology Data Exchange (ETDEWEB)
The neutron-induced fission cross-section of {sup 233}U has been measured at the CERN n-TOF facility relative to the standard fission cross-section of {sup 235}U between 0.5 and 20MeV. The experiment was performed with a fast ionization chamber for the detection of the fission fragments and to discriminate against {alpha} -particles from the natural radioactivity of the samples. The high instantaneous flux and the low background of the n-TOF facility result in data with uncertainties of {approx} 3%, which were found in good agreement with previous experiments. The high quality of the present results allows to improve the evaluation of the {sup 233}U (n,f) cross-section and, consequently, the design of energy systems based on the Th/U cycle. (orig.)
2011-01-15
Neutron cross-sections for next generation reactors: New data from n_TOF
International Nuclear Information System (INIS)
In 2002, an innovative neutron time-of-flight facility started operation at CERN: n_TOF. The main characteristics that make the new facility unique are the high instantaneous neutron flux, high resolution and wide energy range. Combined with state-of-the-art detectors and data acquisition system, these features have allowed to collect high accuracy neutron cross-section data on a variety of isotopes, many of which radioactive, of interest for Nuclear Astrophysics and for applications to advanced reactor technologies. A review of the most important results on capture and fission reactions obtained so far at n_TOF is presented, together with plans for new measurements related to nuclear industry.
2008-06-22
High resolution X ray spectroscopy in light antiprotonic atoms
Energy Technology Data Exchange (ETDEWEB)
At the LEAR facility, CERN, antiprotonic L{alpha} transitions in light elements have been investigated with a focussing crystal spectrometer. The high resolution of the experiment allowed for the first time to resolve in p-barH the 2{sup 3}P{sub 0} state from the close lying states 2{sup 3}P{sub 2}, 2{sup 1}P{sub 1}, and 2{sup 3}P{sub 1}. In p-barD the corresponding transitions were found to be more than an order of magnitude broader. To a large extent the results for p-barH support the meson exchange model.
2000-08-15
The fast rotating wire scanners installed in the PS and the PS booster are used for the precise transversal profile measurements in horizontal and vertical planes. The scanners may show large position measurement errors if no special treatment is applied to the acquired data. The aim of the calibration is to obtain a correction algorithm for the systematic position measurement error due to mechanical and electronic offsets. A new calibration system has been developed and introduced at CERN for the scanners implementing position feedback control. The calibration method is based on a substitution of a particle beam by a laser one where the laser beam position is well known. According to the previous experience the following crucial requirements to the system have been taking into consideration: heavy and mechanically stable design of the calibration bench to reduce mechanical oscillations of scanner parts; automation of the calibration procedure to exclude human ...
2009-01-01
The Large Hadron Collider (LHC) will be equipped with several thousands of superconducting corrector magnets. Among the largest ones are the superconducting trim quadrupoles (MQTL). These twin-aperture magnets with a total mass of up to 1700 kg have a nominal gradient of 129 T/m at 1.9 K and a magnetic length of 1.3 m. Sixty MQTL are required for the LHC, 36 operating at 1.9 K in and 24 operating at 4.5 K. The paper describes the design features, and reports the measured quench performance and magnetic field quality of the production magnets. The MQTL magnet production is shared between CERN and industry. This sharing is simplified due to the modular construction, common to all twin-aperture correctors.
2006-01-01
Decay of Neutron-Rich Mn Nuclides and Deformation of Heavy Fe Isotopes
Energy Technology Data Exchange (ETDEWEB)
The use of chemically selective laser ionization combined with {beta} -delayed neutron counting at CERN/ISOLDE has permitted identification and half-life measurements for 623-ms {sup 61}Mn up through 14-ms {sup 69}Mn . The measured half-lives are found to be significantly longer near N=40 than the values calculated with a quasiparticle random-phase-approximation shell model. Gamma-ray singles and coincidence spectroscopy has been performed for {sup 64,66}Mn decays to levels of {sup 64,66}Fe , revealing a significant drop in the energy of the first 2{sup +} state in these nuclides that suggests an unanticipated increase in collectivity near N=40 . {copyright} {ital 1999} {ital The American Physical Society }
1999-02-01
Decay of Neutron-Rich Mn Nuclides and Deformation of Heavy Fe Isotopes
International Nuclear Information System (INIS)
The use of chemically selective laser ionization combined with #beta# -delayed neutron counting at CERN/ISOLDE has permitted identification and half-life measurements for 623-ms "6"1Mn up through 14-ms "6"9Mn . The measured half-lives are found to be significantly longer near N=40 than the values calculated with a quasiparticle random-phase-approximation shell model. Gamma-ray singles and coincidence spectroscopy has been performed for "6"4","6"6Mn decays to levels of "6"4","6"6Fe , revealing a significant drop in the energy of the first 2"+ state in these nuclides that suggests an unanticipated increase in collectivity near N=40 . copyright 1999 The American Physical Society.
1999-02-01
Conceptual design of a low-temperature radiation-hard tracker detector
Silicon sensors have about ten times improved radiation hardness around 130 K temperature, compared with the state-of-art sensors close to room temperature. This is based on the Lazarus effect studied by the RD39 Collaboration of CERN. Other benefits of low temperatures will also be discussed. We shall describe the conceptual design of low-mass detector modules cooled using two-phase flow of argon in miniature cooling pipes integrated in the module structure between the sensors and the readout hybrid circuit. The main engineering features of the cooling system and mechanical support structures are discussed, as well as the benefits arising from the operation of the tracker under cryogenic vacuum. 4 Refs.
2003-01-01
Energy Technology Data Exchange (ETDEWEB)
This volume is based on the proceedings of the CERN Accelerator School's course on Applied Geodesy for Particle Accelerators held in April 1986. The purpose was to record and disseminate the knowledge gained in recent years on the geodesy of accelerators and other large systems. The latest methods for positioning equipment to sub-millimetric accuracy in deep underground tunnels several tens of kilometers long are described, as well as such sophisticated techniques as the Navstar Global Positioning System and the Terrameter. Automation of better known instruments such as the gyroscope and Distinvar is also treated along with the highly evolved treatment of components in a modern accelerator. Use of the methods described can be of great benefit in many areas of research and industrial geodesy such as surveying, nautical and aeronautical engineering, astronomical radio-interferometry, metrology of large components, deformation studies, etc.
1987-01-01
Annihilation of antiprotons in light nuclei
CR-39 detectors have been exposed to a 5.9-MeV antiproton beam using the low energy antiproton ring (LEAR) facility at CERN. At this energy, tracks of antiprotons appear in a CR-39 detector after 135 min of etching in 6 M NaOH at 70C. Fluence of the antiproton beam has been determined using track density. We have also found tracks in the etched CR-39 detector at different depths (250-500 mum). These tracks have resulted from the annihilation of antiprotons with the constituents (H, C and O) of the CR-39 detector. The goal of the experiment is to develop a simple and low-cost method to study properties of antiparticles and those formed after annihilation of these particles with the target matter.
2006-01-01
A Hundred Years of Physics on Show
The New Yorker Richard Feynman, well known to all physicists for his diagrams. Eleven vivid posters have recently been hung along the Theoretical Physics corridor on the first floor of Building 53. They tell the story of a century of physics, between 1900 and the end of the nineteen-nineties, the century that gave us atomic and quantum physics and the great breakthroughs that have rocked our understanding of the world and the universe. The posters are a gift from the American Physical Society to the CERN Library. As they were designed for high school and university book collections in the US, they necessarily have a somewhat American view of the history of science. But it is still instructive to revisit contemporary physics through its great figures, such as Marie Curie, Stephen Hawking, and Richard Feynman, not to mention Albert Einstein and many others. Why not take the time for a little trip down this particular stretch of Memory Lane?
2002-01-01
A He-gas Cooled, Stationary Granular Target
In the CERN approach to the design of a neutrino factory, the repetition frequency of the proton beam is high enough to consider stationary solid targets as a viable solution for multi-MW beams. The target consists of high density tantalum spheres of 2 mm diameter which can efficiently be cooled by passing a high mass flow He-gas stream through the voids between the Ta-granules. Very small thermal shocks and stresses will arise in this fine grained structure due to the relatively long burst of 3.3 ms from the SPL-proton linac. In a quadruple target system where each target receives only one quarter of the total beam power of 4 MW, conservative temperature levels and adequate lifetimes of the target are estimated in its very high radiation environment. A conceptual design of the integration of the target into the magnetic horn-pion-collector is presented.
2003-01-01
Energy Technology Data Exchange (ETDEWEB)
The simultaneous biosorption of Cr(VI) and Cu(II) on free Rhizopus arrhizus in a packed column operated in the continuous mode was investigated and compared to the single metal ion situation. The breakthrough curves were measured as a function of feed flow rate, feed pH, and different combinations of metal ion concentrations in the feed solutions. Column competitive biosorption data were evaluated in terms of the maximum (equilibrium) capacity in the column, the amount of metal loading on the R. arrhizus surface, the adsorption yield, and the total adsorption yield. In the single-ion situation the adsorption isotherms were developed for optimum conditions, and it was seen that the adsorption equilibrium data fit the noncompetitive Freundlich model. For the multicomponent adsorption equilibrium the competitive adsorption isotherms were also developed. The competitive Freundlich model for binary metal mixtures represented most the column adsorption equilibrium data ...
1999-12-01
Energy Technology Data Exchange (ETDEWEB)
This paper describes the effects of SiC coating on the oxidation resistance of C/C composites in combusting fields, which are expected to be applied to high temperature structural materials at over 1770K. The coating methods employed were CVD and pack cementation. The time changes in weight loss of the specimens were measured at temperatures of 1770K and 1900K under the equivalence ratio of 0.9 generated by methane-air combustion, and the surface of the specimens before and after the experiment was observed by SEM. Although the weight loss of the specimens coated by the CVD method was minimal, the coating layer was easily peeled off from the substrate. On the other hand, the layer of the specimens coated by the pack cementation method was stable and adhered to the substrate, but the substrate was degraded because of penetration of oxygen through the pores in the layer. To cover the pores, the specimens were additionally coated with glass ...
1997-11-01
Nanostructured mesoporous materials for lithium-ion battery applications
The Energy crisis happens to be one of the greatest challenges we are facing today. In this view, much effort has been made in developing new, cost effective, environmentally friendly energy conversion and storage devices. The performance of such devices is fundamentally related to material properties. Hence, innovative materials engineering is important in solving the energy crisis problem. One such innovation in materials engineering is porous materials for energy storage. Porous electrode materials for lithium-ion batteries (LIBs) offer a high degree of electrolyte-electrode wettability, thus enhancing the electrochemical activity within the material. Among the porous materials, mesoporous materials draw special attention, owing to shorter diffusion lengths for Li+ and electronic movement. Nanostructured mesoporous materials also offer better packing density compared to their nanostructured counterparts such as nanopowders, nanowires, nanotubes etc., thus ...
2011-05-01
Densification of ashes from a thermal power plant
Energy Technology Data Exchange (ETDEWEB)
Power plants generate a great amount of ash during coal combustion. From this process two different kinds of ashes are extracted: fly ash (FA) and bottom ash (BA). In this work possible use of both fly and bottom ash as raw material for the ceramic industry is analyzed. The samples were formed by mechanical mixing of both kinds of ashes, and density evolution during conformation as structural ceramic (packing, pressing and sintering) was studied. It was verified that powders with larger fly ash content exhibited higher packing density resulting in compacts with improved green and sintered densities. Preheating treatments at temperatures above 600{sup o}C also increased the green and sintered densities. Dilatometric curves on compacts formed from FA and BA powders were run at constant heating rate and at isothermal cycles. From the analysis of these data it can be established that liquid-phase sintering is the densification mechanism present at ...
2003-07-01
Chromized/siliconized diffusion coatings for iron-base alloy by pack cementation
Energy Technology Data Exchange (ETDEWEB)
This paper reports that the co-deposition of chromium and silicon into a 2.25Cr-1.0Mo-0.15C steel, alloy 800, and type 304 stainless steel has been achieved using the pack cementation process. The ferritic coating produced on the 2.25 Cr-1.0Mo steel was approximately 225 {mu}m (9 mils) thick, whereas the inward diffusion of chromium and silicon produced a two-phase structure of ferrite and austenite for type 304. Chromium and silicon were incorporated into the austenitic solid solution upon diffusion into alloy 800. All coatings had approximately 25 to 35 wt% Cr and 2 to 3% Si at the surface. Cyclic oxidation testing in air of the coated 2.25Cr-1.0Mo steel (T = 700{degrees} C) and type 304 (T = 1035{degrees} C) showed a dramatic decrease in the oxidation kinetics compared to the original uncoated alloys. The cyclic oxidation of alloy 800 was also improved.
1991-09-01
International Nuclear Information System (INIS)
The objective of this report was to evaluate four possible alternative methods of preparing and packaging spent fuel assemblies for geologic disposal against the Reference Process of unmodified spent fuel. The four alternative processes were: (1) End fitting removal, (2) Fission gas venting and resealing, (3) Fuel bundle disassembly and close packing of fuel pins, and (4) Fuel shearing and immobilization. Systems analysis was used to develop a basis of comparison of the alternatives. Conceptual processes and facility layouts were devised for each of the alternatives, based on technology deemed feasible for the purpose. Assessments were made of 15 principal attributes from the technical, operational, safety/risk, and economic considerations related to each of the alternatives, including both the surface packaging and underground repository operations. Specific attributes of the alternative processes were evaluated by assigning a number for each that expressed its ...
In this paper we consider the adsorption of argon on the surface of graphitized thermal carbon black and in slit pores at temperatures ranging from subcritical to supercritical conditions by the method of grand canonical Monte Carlo simulation. Attention is paid to the variation of the adsorbed density when the temperature crosses the critical point. The behavior of the adsorbed density versus pressure (bulk density) shows interesting behavior at temperatures in the vicinity of and those above the critical point and also at extremely high pressures. Isotherms at temperatures greater than the critical temperature exhibit a clear maximum, and near the critical temperature this maximum is a very sharp spike. Under the supercritical conditions and very high pressure the excess of adsorbed density decreases towards zero value for a graphite surface, while for slit pores negative excess density is possible at extremely high pressures. For imperfect pores (defined as pores that cannot ...
2005-08-01
Wettability of binary and ternary alloys of the system Al-Si-Mg with SiC particulates
The authors have presented results of an investigation of wettability of SiC particulates by liquid alloys of the Al-Si-Mg system. The evaluation of wetting has been carried out through the determination of the threshold pressure for infiltration of packed SiC particulates by the liquid alloy. The results indicate that whereas Si and Mg additions do not affect wetting, in the case of the ternary alloys the contact angle decreases in an amount proportional to the content of Mg[sub 2]Si.
1994-12-01
Energy Technology Data Exchange (ETDEWEB)
A study of two forest areas in India investigated how much energy is wasted when high stumps are left after trees are cut to produce wooden boxes for packing the apple harvest. Measurements of the stumps determined the total wood pulp wasted, which was 1191 tons during 1981. The calorific value of the stumps would supply a year's cooking and heating fuels for 747 families of five. Additional fuel is wasted by abandoning the branches and tree tops which are unsuitable for box construction. 5 references, 4 tables.
1984-11-01
Seismic and Rockphysics Diagnostics fo Multiscale Reservoir Textures
Energy Technology Data Exchange (ETDEWEB)
We have continued to finish up our work on analyzing relationships between elastic properties and rock microstructure. We have worked on theoretical models for the effects of sorting and packing on elastic moduli and seismic velocities. After analyzing the scanning acoustic images of shales to quantify textures at different scales, we are now using theoretical inclusion models to quantify the elastic property variation with texture. In the closing phases of this project most of our efforts are now focused on writing up the results and preparing the final reports.
2005-02-01
Regenerative zinc/air and zinc/ferricyanide batteries for stationary power applications
Energy Technology Data Exchange (ETDEWEB)
The authors report a novel configuration for a zinc-particle, packed-bed anode in which an open structure of high hydraulic permeability is maintained indefinitely in a cell with closely spaced walls by the formation of particle bridges and associated gaps. The configuration minimizes electrolyte pumping costs, allows rapid refueling and partial recharge, and provides for 100% zinc consumption. This approach benefits zinc/air fuel batteries by allowing nearly continuous operation and fuel recycle without commercial infrastructure; it benefits Zn/[Fe(CN){sub 6}]{sup {minus}3} batteries by eliminating shape-change and polarization problems found with planar anodes.
1994-05-01
Multi-megajoule Nd: glass fusion laser design
Energy Technology Data Exchange (ETDEWEB)
New technologies make multi-megajoule glass lasers economically feasible. Laser architectures using harmonic switchout, target plane holographic injection, phase conjugation, continuous apodization and higher amplifier efficiencies have been devised. A plan for a multi-megajoule laser which can be built for an acceptable cost relies on manufacturing economies of scale and the demonstration of the new technologies presented here. These include continuous pour glass production, rapid harmonic crystal growth, switching of large blocks of power using larger capcaitors packed more economically and by using large identical parts counts.
1986-04-04
Less BOP running with variable bore rams
Energy Technology Data Exchange (ETDEWEB)
The marine ram-type blowout preventer deployed from an offshore drilling rig has one serious disadvantage, its inaccessibility. A development to promote reliability of the subsea ram-type preventer and reduce the excess running and pulling to charge out rams, is the variable bare ram (VBR). Unlike the standard ram, the VBR has the ability to pack off a range of pipe sizes. Interest in VBR's has been revived and research and development in this equipment goes on at each of three manufacturer's facilities in Houston.
1984-04-01
Energy Technology Data Exchange (ETDEWEB)
Microporous membranes are suitable for the CO{sub 2}-MEA (monoethanolamine) system because the overall mass transfer coefficient K of the membrane is approximately 10 times larger than that of composite membranes consisting of microporous membranes and homogeneous membranes. The overall volumetric mass transfer coefficient K{center_dot} of the hollow-fiber contact is more than 5 times larger than that of a conventional packed bed, which suggests that adorption using the present method has the advantage of making the absorption more compact. 8 refs., 7 figs., 4 tabs.
1994-12-31
Feasibility study on scheme of disposing spent guide tubes at Daya Bay nuclear power plant
International Nuclear Information System (INIS)
The author describes feasibility study on the scheme of disposing spent guide tubes at Daya Bay nuclear power plant, including scheme selection, packing cask design, disposal operation and technological process, budget estimation and safety evaluation. The research results show that the new scheme is feasible on technology, and reasonable on budget. If the scheme is adopted to dispose the spent guide tubes at Daya Bay nuclear power station, it can not only save large funds, but also accumulate experience on disposing non-compressible low and intermediate level solid radioactive wastes produced at nuclear power station for the country
1998-12-01
Development of flue gas carbon dioxide recovery technology
Energy Technology Data Exchange (ETDEWEB)
As a counter measure to protect against global warming, the development of CO{sub 2} recovery technology from fossil fuel power plant flue gas has continued. MEA processes are widely used for CO{sub 2} recovery from combustion flue gas in average use etc. However, if we consider power plant scale CO{sub 2} recovery, the biggest theme is the reduction of energy needed to recover CO{sub 2}. The paper focuses on sterically hindered amines and a new absorber packing. Also optimum steam system analysis results are indicated. 1 ref., 16 figs., 3 tabs.
1994-12-31
Desorption of CO{sub 2} from MDEA and activated MDEA solutions
Energy Technology Data Exchange (ETDEWEB)
A packed column was used for investigating the desorption rate of CO{sub 2} from aqueous methyldiethanolamine (MDEA) and activated MDEA solutions. Experiments were conducted within the temperature range 30--70 C, the concentration of MDEA was 4.28 kmol/m{sup 3}, and the concentration of piperazine (PZ) was 0.10 kmol/m{sup 3} for aqueous activated MDEA solutions. Experimental data confirmed that the kinetics model of absorption CO{sub 2} into aqueous MDEA and activated MDEA solutions can be applicable to the situations in which desorption occurs, and the desorption rate of model predictions agree well with that of experimental determination.
1995-03-01
Energy Technology Data Exchange (ETDEWEB)
The performance of a solar chemical heat pipe was studied using CO{sub 2}reforming of methane as the endothermic reaction. A directly heated vertical reactor, packed with a rhodium catalyst was used. The solar tests were carried out in the Schaeffer solar furnace of the Weizmann Institute of Science. The power absorbed was up to 6.3 KW, the maximal flow rates of the gases reached 11,000 1/h, and the methane conversions reached 85%. A computer model was developed to simulate the process. Agreement of the calculations with the experimental results was quite satisfactory.
1992-01-01
Chemical and Process - EA BOOKS
... Focuses on distillation and packed towers, and presents the methods and fundamentals of plant design along with supplemental mechanical and related data, nomographs, data charts and heuristics. AU$223.45 ex-GST Terms and Conditions Microchemical Engineer... Provides the information chemists and engineers need to evaluate the use of microreactors, covering the technical, operational, and economic considerations for various applications. AU$136.36 ex-GST Terms and Conditions Perry's Chemical Engin... Was: $199.95 inc gst NOW: $129.95 Special Price ...
Chemical and Process - EA BOOKS
... Focuses on distillation and packed towers, and presents the methods and fundamentals of plant design along with supplemental mechanical and related data, nomographs, data charts and heuristics. AU$223.45 ex-GST Terms and Conditions Browse Product Pages My EA Books Customer sign in User name Password Forgot your password? Register Mailing Lists New Books - Promotions click here to subscribe Shopping basket 50 Products AU$5,482.58 Standard Post Australia AU$10.00 Total amount AU$5,492.58 Display shopping basket Check out Copyright ©Engineers Media 2008 Terms &...
Chemical and Process - EA BOOKS
... Focuses on distillation and packed towers, and presents the methods and fundamentals of plant design along with supplemental mechanical and related data, nomographs, data charts and heuristics. AU$223.45 ex-GST Terms and Conditions CRC Handbook of Chemis... For almost a century this handbook has been updated annually, except for a few wartime years, and has served generations of engineers and scientists. Current daily price AU$209.09 ex-GST Terms and Conditions Perry's Chemical Engin... Was: $199.95 inc gst NOW: ...
Overview of electrochemical power sources for electric and hybrid-electric vehicles.
Energy Technology Data Exchange (ETDEWEB)
Electric and hybrid-electric vehicles are being developed and commercialized around the world at a rate never before seen. These efforts are driven by the prospect of vehicles with lower emissions and higher fuel efficiencies. The widespread adaptation of such vehicles promises a cleaner environment and a reduction in the rate of accumulation of greenhouse gases, Critical to the success of this technology is the use of electrochemical power sources such as batteries and fuel cells, which can convert chemical energy to electrical energy more efficiently and quietly than internal combustion engines. This overview will concentrate on the work being conducted in the US to develop advanced propulsion systems for the electric and hybrid vehicles, This work is spearheaded by the US Advanced Battery Consortium (USABC) for electric vehicles and the Partnership for a New Generation of Vehicle (PNGV) for hybrid-electric vehicles, both of which can be read about on the world wide web ...
1999-02-12
High resolution electron microscopy of interfaces in fcc materials
Energy Technology Data Exchange (ETDEWEB)
Modern high-resolution electron microscopy (HREM) instruments, which are capable of a point-to-point resolution of better than 0.2 nm, have allowed atomic-scale observations of a variety of internal interfaces. The application of the HREM technique to fcc model systems for the purpose of addressing a number of interface issues will be examined in this paper. Atomic structure observations for heterophase interfaces of metal/metal and metal/metal-oxide systems as well as HREM studies of grain boundaries in NiO and Au will be discussed with emphasis on generic structural features and the role of the interface plane. Comparisons between observed interface structures and atomistic computer modeling results have shown agreements for some interfaces, as well as certain differences in others. A number of structural features are common to both metal and oxide grain boundaries, as well as certain heterophase boundaries. Of particular importance in close-packed solids appears ...
1990-08-01
Energy Technology Data Exchange (ETDEWEB)
Cassava is cultivated almost all over the world and it is considered one of the most important nutritious sources of calories in the human diet. Cassava is a viable food against starvation in several poor areas of the world because it is an extremely resistant culture and may reach satisfactory economical yield. We utilized vacuum packed industrialized cassava irradiated with 0,1 kGy, 3kGy and 5kGy and stored under refrigeration for 1, 21, 30 and 50 days. Our objective was to analyse the synergistic effect of vacuum packing, irradiation and refrigeration on the preservation of minimally processed cassava. The samples were analyzed for pH, acidity, weight, humidity, texture and color. The irradiation did not affect the chemical characteristics of the cassava. Neither the pH nor the acidity, the most relevant variables to verify deterioration in cassava, presented significant alterations during the period of storage. Comparing the irradiated ...
2005-07-01
Development on the technologies for tritium removal processes
Energy Technology Data Exchange (ETDEWEB)
While tritium exposure to the site-workers in Wolsung NPP is upto about 40 % of the total personnel exposure, Korea Institute of Nuclear Safety has asked tritium removal facility, as one of the requirements for post reactor construction, after operation of four CANDU reactors in Wolsung site. For the purpose of essential removal of tritium from the heavy water system of the heavy water reactors, an experiment of Ar-N{sub 2} cryogenic distillation tower was carried out as a preliminary study for development of liquid-phase catalytic exchange - cryogenic hydrogen distillation process. The steady-state reached after 50 minutes under 90 K in the Ar-N{sub 2} distillation column (inner diameter 20 mm, height 500 mm) packed with Dixon ring ({phi} 3 mm x H 3 mm), and the ratios of Ar-concentration at the top and at the bottom measured by gas chromatography within {+-}1 % relative error was approximately 93 : 3. This value was distillation performances quite higher than ...
1994-12-01
Energy Technology Data Exchange (ETDEWEB)
CeO{sub 2}-TiO{sub 2} catalysts are prepared by coprecipitation method, and the activity and stability in the catalytic wet air oxidation (CWAO) of phenol are investigated in a batch reactor and packed-bed reactor. CeO{sub 2}-TiO{sub 2} mixed oxides show the higher activity than pure CeO{sub 2} and TiO{sub 2}, and CeO{sub 2}-TiO{sub 2} 1/1 catalyst displays the highest activity in the CWAO of phenol. In a batch reactor, COD and TOC removals are about 100% and 77% after 120 min in the CWAO of phenol over CeO{sub 2}-TiO{sub 2} 1/1 catalyst at reaction temperature of 150 {sup o}C, the total pressure of 3 MPa, phenol concentration of 1000 mg/L, and catalyst dosage of 4 g/L. In a packed-bed reactor using CeO{sub 2}-TiO{sub 2} 1/1 particle catalyst, over 91% COD and 80% TOC removals are obtained at the reaction temperature of 140 {sup o}C, the air total pressure of 3.5 MPa, the phenol concentration of 1000 mg/L for 100 h continue reaction. Leaching ...
2008-05-30
Production and decay of scalar top squarkonium bound states
International Nuclear Information System (INIS)
In this paper we discuss possible signatures for the production of scalar t_1t_1"* (top squarkonium) bound states #sigma#_t_1 at hadron colliders, where t_1 is the lighter scalar top eigenstate. We first study the decay of #sigma#_t_1; explicit expressions are given for all potentially important decay modes. If t_1 has unsuppressed two-body decays, they will always overwhelm the annihilation decays of #sigma#_t_1. Among the latter, we find that usually either the gg or hh final state dominates, depending on the size of the off-diagonal entry of the top squark mass matrix; h is the lighter neutral scalar Higgs boson of the minimal supersymmetric model. If m_#sigma#_t happens to be close to the mass of one of the neutral scalar Higgs bosons, Q bar Q final states dominate (Q=b or t). W"+W"- and ZZ final states are subdominant. We argue that #sigma#_t_1#->##gamma##gamma# decays offer the best signal for top squarkonium production at hadron colliders. The Fermilab Tevatron should be able ...
Deployment Support Leading to Implementation
Energy Technology Data Exchange (ETDEWEB)
The following paragraphs summarize the progress of each research project funded under the WVU Cooperative Agreement during the third quarter of 1997 (July - September 1997). The projects are arranged according to their 1997 WVU task number. WVU Focus Area 1.0: Subsurface Contaminants, Containment and Remediation Task No. 1.1: Project discontinued. Task No. 1.2: Development of Standard Test Protocols and Barrier Design Models for Desiccation Barriers (K. Amininan & S. Ameri): A number of experiments were preformed this period to evaluate the ability of the dried sand-packs to act as a barrier to liquids. Water infiltration tests were done with a constant head, dispersing 80 ml of water, and by adding water in small increments. Results indicate that when the water is spilled over the sand-pack, it has the tendency to channel through the sand-pack, significantly reducing the capacity of the dried zone to retain liquid ...
1997-10-01
In vitro MRI of brain development
International Nuclear Information System (INIS)
In this review, we demonstrate the developmental appearance, structural features, and reorganization of transient cerebral zones and structures in the human fetal brain using a correlative histological and MRI analysis. The analysis of postmortem aldehyde-fixed specimens (age range: 10 postovulatory weeks to term) revealed that, at 10 postovulatory weeks, the cerebral wall already has a trilaminar appearance and consists of: (1) a ventricular zone of high cell-packing density; (2) an intermediate zone; (3) the cortical plate (in a stage of primary consolidation) with high MRI signal intensity. The anlage of the hippocampus is present as a prominent bulging in the thin limbic telencephalon. The early fetal telencephalon impar also contains the first commissural fibers and fornix bundles in the septal area. The ganglionic eminence is clearly visible as an expanded continuation of the proliferative ventricular zone. The basal ganglia showed an initial aggregation of ...
2006-02-01
CO2 Capture by Absorption with Potassium Carbonate
Energy Technology Data Exchange (ETDEWEB)
The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO3 promoted by piperazine (PZ). Pilot plant testing was performed in a 16.8-inch ID absorber and stripper with recirculation of air and CO{sub 2}. Three solvents (7 m MEA, 5 m K{sup +}/2.5 m PZ, and 6.4 m K{sup +}/1.6 m PZ) were tested in four campaigns with three different absorber packings. Pilot plant testing established that 5 m K{sup +}/2.5 m PZ requires two times less packing than 7 m MEA and three times less packing than 6.4 m K{sup +}/1.6 m PZ. A rigorous model of the thermodynamics and mass transfer was developed in the RateSep{trademark} block of AspenPlus{reg_sign}. The double matrix stripper reduces energy consumption by 5 to 15%. The best K{sup +}/PZ solvent, 4 m K{sup +}/4 m PZ, and the best process configuration, double matrix stripper with a ...
2007-08-31
The Authenticated Tracking and Monitoring System (ATMS) concept
Energy Technology Data Exchange (ETDEWEB)
The Authenticated Tracking and Monitoring System (ATMS) has been designed to address the need for global monitoring of the status and location of proliferation-sensitive items. Conceived to utilize the proposed Global Verification and Location System (GVLS) satellite link, ATMS could use the existing International Maritime Satellite commercial communication system until GVLS is operational. The ATMS concept uses sensor packs to monitor items and environmental conditions, collects a variety of events data through a sensor processing unit, and transmits the data to a satellite, which then sends data to ground stations. Authentication and encryption algorithms will be used to secure the data. A typical ATMS application would be to track and monitor the safety and security of a number of items in transit along a scheduled shipping route. This paper also discusses a possible proof-of-concept system demonstration.
1993-08-01
Synthesis of magnetic particles via a cationic-anionic surfactant vesicle method
Energy Technology Data Exchange (ETDEWEB)
In this work, a mixed cationic--anionic [i.e. cetyltrimethylammonium bromide-sodium octyl sulphate] surfactant system was used to synthesize the magnetite particles. The loading content of iron ions (Fe{sup 3+} and Fe{sup 2+}) into the surfactant system was varied to study its effect on the formation of magnetite, magnetic and morphological properties of the magnetite particles encapsulated by the surfactant vesicles. It has been verified that the vesicle-encapsulated magnetite particles with sizes from 100 to 200 nm were formed, which were almost independent of the loading content of iron ions. However, the morphological structure of the magnetite particles was dependent on the loading content of iron ions and there existed an optimal loading content for a full packing of the surfactant vesicles with the magnetite particles.
2006-10-15
Synthesis of magnetic particles via a cationic-anionic surfactant vesicle method
International Nuclear Information System (INIS)
In this work, a mixed cationic--anionic [i.e. cetyltrimethylammonium bromide-sodium octyl sulphate] surfactant system was used to synthesize the magnetite particles. The loading content of iron ions (Fe"3"+ and Fe"2"+) into the surfactant system was varied to study its effect on the formation of magnetite, magnetic and morphological properties of the magnetite particles encapsulated by the surfactant vesicles. It has been verified that the vesicle-encapsulated magnetite particles with sizes from 100 to 200 nm were formed, which were almost independent of the loading content of iron ions. However, the morphological structure of the magnetite particles was dependent on the loading content of iron ions and there existed an optimal loading content for a full packing of the surfactant vesicles with the magnetite particles.
2006-10-01
Energy Technology Data Exchange (ETDEWEB)
Medicinal plants i.e. dried seeds of myristica argentea, myristica fragrans, coriandrum sativum and foeniculum vulgare were stored for 0 and 6 months, with and without gamma irradiation at 5 kGy. No detectable changes were seen in infrared and UV spectra, GLC chromatograms and refraction indices of steam distilled, essential oils from the irradiated medicinal plants. The same results were also obtained from irradiated samples stored for 6 months at ambient conditions. Storage for 6 months caused significant changes in the gas liquid chromatograms and UV spectra of all samples compared to non-stored samples. The moisture content of all samples packed in polyethylene bags seems to be constant after 6 months of storage. No measurable changes were found in the amount of essential oil content caused by irradiation.
1981-10-01
British Library Electronic Table of Contents (United Kingdom)
Summary 1. In the Greater Yellowstone Ecosystem, bison Bison bison and elk Cervus canadensis nelsoni act as hosts for Brucella abortus. The presence of B. abortus within wildlife populations is an important conservation issue because of the risk of brucellosis transmission from wildlife to cattle. 2. We investigated conditions facilitating contact between bison (40-60% seroprevalence) and elk on a shared winter range in the Madison headwaters area of Yellowstone National Park. We evaluated the effects of snow pack, season, elk and bison population sizes, and wolf Canis lupus predation risk on the degree of spatial overlap between bison and elk from 1991 to 2006. 3. Sixty-eight per cent of 10 093 independent elk observations occurred within the known bison wintering range, 29% occurred with...
2010-01-01
Renewable resources | Greener Package
... Database listings you may be interested in: 3rd Party Reviewed Listings Sustainable Industrial Paper Strap - Natural & White High strength, sustainable, recyclable paper strap SDF Strapping, Inc. High Graphics Litho Lam Corrugated High Graphics Corrugated Packaging (Litho-Lam) Accurate Box Company, Inc. EcoSystem Packaging Solution Starch-based loosefill packing peanut system StarchTech GreenChoice 100 100% recycled, clay-coated paperboard Strathcona Paper, L.P. Greener Package Database! comprehensive sustainability data on packaging materials searchable by converted package or raw material standardizes reporting of sustainability claims many ...
Energy Technology Data Exchange (ETDEWEB)
As thin films become increasingly popular (for solar cells, LEDs, microelectronics, batteries), quantitative morphological information is needed to predict and optimize the film's electronic, optical and mechanical properties. This quantification can be obtained quickly and easily with X-ray diffraction using an area detector and synchrotron radiation in two simple geometries. In this paper, we describe a methodology for constructing complete pole figures for thin films with fiber texture (isotropic in-plane orientation). We demonstrate this technique on semicrystalline polymer films, self-assembled nanoparticle semiconductor films, and randomly-packed metallic nanoparticle films. This method can be immediately implemented to help understand the relationship between film processing and microstructure, enabling the development of better and less expensive electronic and optoelectronic devices.
2010-02-19
Production of carrier free 188Re radioisotope generator based on aluminum tungstate matrix
British Library Electronic Table of Contents (United Kingdom)
Improved radionuclide generator include a substantially insoluble salt of a radioactive parent which may be directly packed in column for subsequent elution of the daughter radionuclide. An improved 188Re generator was prepared by reacting a radioactive tungsten (188W) as parent radionuclide incorporated with aluminum chloride to obtain an insoluble radioactive aluminum tungstate matrix. The investigated matrix was characterized on the basis of the chemical composition, IR, thermal analysis and mechanical stabilities. The factors affecting the elution performance were studied such as influence of pH, molar ratio and drying temperature. From the obtained data, the molar ratio W:Al was 1.5:1 at pH?=?4, the matrix dried at 105??C for 2 h. Chromatographic and multichannel analysis has been cur...
2010-01-01
Process for treatment of detergent-containing radioactive liquid wastes
Energy Technology Data Exchange (ETDEWEB)
A detergent-containing radioactive liquid waste originating from atomic power plants is concentrated to have about 10 wt. % detergent concentration, then dried in a thin film evaporator, and converted into powder. Powdered activated carbon is added to the radioactive waste in advance to prevent the liquid waste from foaming in the evaporator by the action of surface active agents contained in the detergent. The activated carbon is added in accordance with the COD concentration of the radioactive liquid waste to be treated, and usually at a concentration 2-4 times as large as the COD concentration of the liquid waste to be treated. A powdery product having a moisture content of not more than 15 wt. % is obtained from the evaporator, and pelletized and then packed into drums to be stored for a predetermined period.
1984-02-21
Process for treatment of detergent-containing radioactive liquid wastes
International Nuclear Information System (INIS)
A detergent-containing radioactive liquid waste originating from atomic power plants is concentrated to have about 10 wt. % detergent concentration, then dried in a thin film evaporator, and converted into powder. Powdered activated carbon is added to the radioactive waste in advance to prevent the liquid waste from foaming in the evaporator by the action of surface active agents contained in the detergent. The activated carbon is added in accordance with the COD concentration of the radioactive liquid waste to be treated, and usually at a concentration 2-4 times as large as the COD concentration of the liquid waste to be treated. A powdery product having a moisture content of not more than 15 wt. % is obtained from the evaporator, and pelletized and then packed into drums to be stored for a predetermined period.
1984-02-01
Plane-wave-basis pseudopotential calculations of the surface relaxations of Ti(0001) and Zr(0001)
International Nuclear Information System (INIS)
The relaxations of the Ti(0001) and Zr(0001) surfaces are studied using the plane-wave-basis pseudopotential method within the local-density approximation. We find that the first interlayer spacings of Ti(0001) and Zr(0001) are contracted with respect to the bulk spacings by 6.8% and 6.1%, respectively. Such large relaxations for the close-packed surfaces of Ti and Zr are in good agreement with recent linear-augmented-plane-wave calculations. In addition, we predict a weak vibrational effect on the surface relaxation of Zr(0001) by considering the free energy in the quasiharmonic approximation. This result can be attributed to a very strong bonding between the first- and second-layer Zr atoms as a consequence of the bond-order endash bond-length correlation. copyright 1997 The American Physical Society.
Photodestruction of explosives in process water
Energy Technology Data Exchange (ETDEWEB)
Photodestruction has received much attention in recent years. In particular, titanium dioxide (TiO{sub 2}) and ozonolysis have attained a position of prominence. These technologies hold promise for the destruction of trace amounts of aqueous high explosives that are generated by load and pack operations, as well as demilitarization activities. Currently this water is treated by passing through a bed of activated carbon. The carbon is then steam regenerated and reused, thus creating a second waste stream which must be disposed of, or the carbon is burned directly. Recent trends in environmental regulation have shown that this may not be a viable option for process water remediation in the future. This talk will discuss efforts to employ alternate aqueous treatment techniques that not only remove the explosives compounds but are able to transform the parent compound into carbon dioxide and water. Titanium dioxide photocatalysis as well as UV-ozone photolysis will be ...
1995-12-31
Performance of high-temperature central receiver systems
Energy Technology Data Exchange (ETDEWEB)
The development of central receiver technology for the production of electricity is reasonably well established. One possible direction for future research and development efforts funded by the Department of Energy is high-temperature, high-performance systems. In this paper, the performance of central receiver systems is investigated for a range of heliostat sizes, field configurations, plant sizes, and receiver temperatures. The maximum plant efficiency achievable in a central receiver system that uses simple cavity geometry is shown for a range of receiver temperatures. The impact of changes in heliostat size, field packing density, and canting and focusing strategies on system efficiency are investigated over a range of plant sizes. The results of the study underscore the importance of accommodating high absorber plane fluxes in order to efficiently produce working temperatures at or above 1200/sup 0/C.
1984-07-01
British Library Electronic Table of Contents (United Kingdom)
A dense Pd-Ag membrane reactor (MR) with 100% hydrogen selectivity packed with either Rh/La2O3 or Rh/La2O3-SiO2 as catalysts was used to carry out the dry reforming of methane. The membrane reactor simulation was performed using a well-known reactor model. For this purpose, we employed the equations derived from complete kinetic studies of the dry reforming of methane reaction in connection with both catalysts. In addition, we developed the kinetic equation for the reverse water gas shift reaction (RWGS). The combination of detailed kinetic studies with the measured permeation flux for the Pd-Ag membrane allowed a complete comparison between experimental and simulated operation variables. The variables studied for both catalysts were methane conversion and hydrogen permeation as a function...
2011-01-01
Optimization techniques for parameter estimations: case studies in CO{sub 2} separation processes
Energy Technology Data Exchange (ETDEWEB)
Application of an optimization technique to extract the non-ideal parameters of gas absorption with chemical reactions process was described. The gas absorption was modeled using mass transfer theory to represent the realistic behaviors of an absorber. The model was a highly non-linear iterative model which correlated the overall rate of absorption as the function of unknown non-ideal parameters, including the physical liquid mass transfer coefficient and the wetted interfacial area of of packings. The optimization program was developed to minimize the sum of squares of relative errors between the model predictions and the experimental data. Four sets of experimental data (case studies) with different operating conditions were used for extracting parameters. Comparisons between predicted and experimental measured overall absorption rate were in good agreement, average absolute value of relative errors not exceeding 5.4 %. 18 refs., 3 tabs., 4 figs.
1995-12-31
In 1934, Reinhardt asked for the centrally symmetric convex domain in the plane whose best lattice packing has the lowest density. He conjectured that the unique solution up to an affine transformation is the smoothed octagon (an octagon rounded at corners by arcs of hyperbolas). This article offers a detailed strategy of proof. In particular, we show that the problem is an instance of the classical problem of Bolza in the calculus of variations. A minimizing solution is known to exist. The boundary of every minimizer is a differentiable curve with Lipschitz continuous derivative. If a minimizer is piecewise analytic, then it is a smoothed polygon (a polygon rounded at corners by arcs of hyperbolas). To complete the proof of the Reinhardt conjecture, the assumption of piecewise analyticity must be removed, and the conclusion of smoothed polygon must be strengthened to smoothed octagon.
2011-01-01
International Nuclear Information System (INIS)
A mathematical model of multichannel radiometric inspection system was developed, in which the measurement results are reproduced in the form of a half-tone image equivalent to the radiation image of the irradiated object. The model makes the following assumptions: the beam of radiation is fan-shaped; the object of inspection is scanned discretely; the focal spot of the source is rectangular; the apertures of the detector are round, and the detectors themselves are equidistant from the sources, aimed at it, and form a close-packed array; the signals from the detectors are processed according to a time scheme; and the measurement results are corrected in a computer for normalizing the gains of the channels of the system. The mathematical model can serve as the basis for developing a method of calculating the optimal parameters of a multichannel radiometric system with visualization of the radiation images. 14 refs., 2 figs.
Energy Technology Data Exchange (ETDEWEB)
On efficient glass capillary columns packed with graphitized thermal carbon black (GTCB) the stereoisomers of aromatic and saturated tricyclic hydrocarbons are completely separated and identified. The Henry's adsorption constants of the individual isomers were determined from mixture at different temperatures. Five isomers of perhydroanthracene, five isomers of perhydrofluorene, two isomers of perhydrophenalene, four isomers of perhydroacenaphthene, as well as phenalene, dihydrophenalene, acenaphthene and acenaphthylene were investigated. The increase of the hydrogenization degree of unsaturated tricyclic hydrocarbons reduces the retention. Among the saturated tricyclic isomers the retention becomes shorter with the larger bending of the molecules, i.e. from the molecule having more equatorial bonds to the molecules having more axial connections. The experimentally determined Henry's constants were qualitatively compared with the structure of the ...
1984-04-01
Microstructure characterization and tensile properties of b phase containing TiAl pancake
British Library Electronic Table of Contents (United Kingdom)
The microstructure and tensile properties of Ti-44Al-6V-3Nb-0.3Y (at.%) alloy after canned forging were investigated. SEM results showed that the TiAl pancake exhibits inhomogeneous microstructure, which can be ascribed to the temperature drop and friction between billet and outer pack during forging, as well as the intrinsic anisotropy of lamellar colony. By means of TEM observation and EBSD analysis, the microstructure in the dominant area of the pancake was further characterized. This deformation area consists of 87.7% content of g grains plus some refined lamellar colonies and the rest of B2 grains. The grain size ranges between 1mm and 8.5mm. High-angle boundaries dominate the deformation microstructure, several substructures and twins are observed as well. Additionally, current forge...
2011-01-01
International Nuclear Information System (INIS)
The separation and the mechanism of retention of ion associates of #alpha#-isomers of molybdic and tungstic heteropoly acids (HPA) of phosphorus(5), silicon(4), and germanium(4) with trioctylamine (TOA) on a column (80x3 mm) packed with Diasorb-130-CN (8 #mu#m) were studied in a flow of chloroform-tetrahydrofuran (THF) and chloroform-n-butanol-TOA mixtures with spectrophotometric detection at 320 nm. It is demonstrated that the adsorption of all the studied ion associates proceeds through the displacement THF molecule from the surface of the stationary phase and without the displacement of TOA molecules. Conditions for the separation of phospho- and silicomolybdic HPA and also phospho- and germanolybdic HPA were found. The chromatographic system using silica gel modified with nitrile groups as the stationary phase is of higher selective than that using ummodified silica gel.
Jamming in granular hopper flow.
Energy Technology Data Exchange (ETDEWEB)
Large-scale three dimensional molecular dynamics simulations of hopper flow are presented. The flow rate of the system is controlled by the width of the aperture at the bottom. As the steady-state flow rate is reduced, the force distribution P(f) changes only slightly, while there is a large change in the impulse distribution P(i). In both cases, the distributions show an increase in small forces or impulses as the systems approach jamming, the opposite of that seen in previous Lennard-Jones simulations. This occurs dynamically as well for a hopper that transitions from a flowing to a jammed state over time. The final jammed P(f) is quite distinct from a poured packing P(f) in the same geometry. The change in P(i) is a much stronger indicator of the approach to jamming. The formation of a peak or plateau in P(f) at the average force is not a general feature of the approach to jamming.
2005-06-01
Investigation of Hg volatile losses from samples and standards during neutron activation analysis
International Nuclear Information System (INIS)
The losses of Hg from phenol formaldehyde resin - bound standards and hair samples in neutron activation analysis in case of their irradiation in the water filled nuclear reactor channel is studied. The mean losses of Hg during 20-30 hrs irradiation at (2-3)x10"1"8 n/cm"2 are 15-20% with their stopping at double Al-covers. The mean losses of Hg from standards at 200, 250 and 300 deg C are 30, 61 and 86% respectively and do not occur at 150 deg C after their 5 hour heating. The losses of Hg from hair samples packed in polyethylene tubes through the package walls in experimental conditions are not observed.
Internal strain and texture evolution during deformation twinning in magnesium
Energy Technology Data Exchange (ETDEWEB)
The development of a twinned microstructure in hexagonal close-packed rolled magnesium compressed in the in-plane direction has been monitored in situ with neutron diffraction. The continuous conversion of the parent to daughter microstructure is tracked through the variation of diffraction peak intensities corresponding to each. Approximately 80% of the parent microstructure twins by 8% compression. Elastic lattice strain measurements indicate that the stress in the newly formed twins (daughters) is relaxed relative to the stress field in the surrounding matrix. However, since the daughters are in a plastically 'hard' deformation orientation, they quickly accumulate elastic strain as surrounding grains deform plastically. Polycrystal modeling of the deformation process provides insight about the crystallographic deformation mechanism involved.
2005-06-15
Improving protein quality of soybean through induced mutations
International Nuclear Information System (INIS)
Soybean is one of the most economical and nutritious food packed with basic nutrients that combat diseases stemming from mal- and under-nutrition. Despite its rich nutritional profile, use of soybean in food has been limited because soybean proteins are often associated with compounds, which could exert a negative impact on the nutritional quality of the protein. Trypsin inhibitor (TI) is one of the important anti-nutritional factors that exert negative effect by causing growth inhibition. Soybean cultivar VLS-2 was irradiated with 250 Gy gamma rays in a gamma cell (200) with 60Co source installed at BARC to induce mutations for low trypsin inhibitor content. Three mutants with lower levels of TI content were identified and can be utilized for developing elite varieties of soybean. (author)
2011-02-22
British Library Electronic Table of Contents (United Kingdom)
A qualitative method, involving supported liquid?liquid extraction (SLE) and ultra high pressure liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS?MS), was developed for the rapid tentative identification of various drugs of abuse in urine. In this study, 28 drugs and metabolites were covered by the screening procedure. Before analysis, urine samples were extracted by SLE and good extraction recoveries were obtained for most investigated compounds. The UHPLC strategy was then selected for the rapid separation of amphetamines, cocaine, opiates and related compounds in urine. Using columns packed with sub-2??m particles, analysis time was reduced down to 2?min, while maintaining acceptable performance. Finally, the detection was by tandem MS operating in the single reaction...
2009-01-01
International Nuclear Information System (INIS)
Presented in this report are the quantitative and qualitative aspects of the more than 5,800 applications of Grafoil on-plant. The subject all-graphite product was originally made by the Union Carbide Corporation. Its utilization in the forms of valve packing, gasketing and sealant tapes for leak repair and prevention on-plant since March 1970 is marked with typical zero-leak results. For all practical purposes, the successful results with Grafoil implementation indicate an unqualified control of leakage problems that began in 1967 with the V-11 and V-12 valves in the primary system of N Reactor. Meaningfully, the accruals of savings with existing and future applications shall continue to be incalculable in personnel exposure, maintenance, and capital. Inherent in the savings are the devised methodology and innovative developments coordinately employed in resolving the leak repair problems.
Energy Technology Data Exchange (ETDEWEB)
The possibility of employing a number of adsorbents (polyphenylquinoxaline, Tenax GC, Carbopak C, graphitized thermal carbon black, silica gels modified with pyrocarbon or hexamethyldisilazane) for the trapping of organic traces from air has been investigated. Adsorption capacities of these adsorbents with respect to a number of volatiles released from certain plastics used as building material (polyvinylchloride, Relin, Acronal, etc.) have been measured. A number of the volatiles were identified by gas chromatography - mass-spectrometry after trapping on the adsorbents investigated. Chromatographic separation after trapping on the adsorbents was carried out on wall-coated open-tubular capillary columns as well as in capillary columns packed with graphitized thermal carbon black.
1983-10-01
Energy Technology Data Exchange (ETDEWEB)
We demonstrate experimentally that the route to a jammed state for a set of bi-dispersed frictional disks, subjected to uni-axial compression from a random initial unjammed state, consists of a consolidation state, a fragile jammed state, and finally a rigid jammed state. In the consolidation regime, the pressure on the sides increases very slowly with the packing fraction {phi} and there are no detectable stress chains. In the fragile jammed state, stress chains are visible, the pressure increases exponentially with {phi}, and the fraction of moving disks drops exponentially. Eventually, a final regime where particle displacements are below our resolution and the pressure varies approximately linearly with {phi} is reached. We argue that this scenario is generic for ather mal frictional compressed particles.
2009-01-01
First derivative of the hard-sphere radial distribution function at contact
Energy Technology Data Exchange (ETDEWEB)
Molecular dynamics simulations have been carried out of the radial distribution function of the hard sphere fluid for a range of densities in the equilibrium fluid and just into the metastable region. The first derivative of the hard-sphere radial distribution function at contact was computed and its density dependence fitted to a simple analytic form. Comparisons were made with semi-empirical formulae from the literature, and of these the formula proposed by Tao et al (1992 Phys. Rev. A 46 8007) was found to be in best agreement with the simulation data, although it slightly underestimates the derivative at the higher packing fractions in excess of about 0.45. Close to contact, within a few per cent of the particle diameter, the radial distribution function can be represented well by a second order polynomial. An exponential function, which has some useful analytic features, can also be applied in this region.
2006-08-16
British Library Electronic Table of Contents (United Kingdom)
Abstract A series of studies performed at our center demonstrates that gaseous microemboli (GME) remain a challenge in cardiac surgical procedures. Evaluation of novel oxygenators must address hemodynamic parameters and microemboli capture capability. The objective of this study is to compare two neonatal membrane oxygenators, the Quadrox i (MAQUET Cardiopulmonary AG, Hirrlingen, Germany) and the Capiox RX05 (Terumo Corporation, Tokyo, Japan), with respect to GME capture and hemodynamic energy delivery. The experimental circuit included a Maquet HL 20 heart lung machine, a Heater Cooler Unit HCU 30 (MAQUET Cardiopulmonary AG), a membrane oxygenator (Quadrox i Neonatal or Capiox RX05), and inch tubing from the COBE Heart/Lung Perfusion Pack (COBE Cardiovascular, Inc., Arvada, CO, USA). A Ca...
2010-01-01
Entropy and Hausdorff Dimension in Random Growing Trees
We investigate the limiting behavior of random tree growth in preferential attachment models. The tree stems from a root, and we add vertices to the system one-by-one at random, according to a rule which depends on the degree distribution of the already existing tree. The so-called weight function, in terms of which the rule of attachment is formulated, is such that each vertex in the tree can have at most K children. We define the concept of a certain random measure mu on the leaves of the limiting tree, which captures a global property of the tree growth in a natural way. We prove that the Hausdorff and the packing dimension of this limiting measure is equal and constant with probability one. Moreover, the local dimension of mu equals the Hausdorff dimension at mu-almost every point. We give an explicit formula for the dimension, given the rule of attachment.
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
This paper is concerned with the study of the Electrorheological RayleighTaylor instability (ERTI) at the interface between a densely packed saturated poorly conducting couple stress porous layer accelerated by a lighter poorly conducting couple stress fluid in a thin shell in the presence of a transverse electric field and laser radiation. A simple theory based on fully developed flow approximations is used to derive the dispersion relation for the growth rate of ERTI. The cutoff and the maximum wave numbers and the corresponding maximum frequencies are obtained. It is shown that the effects of couple stress parameter and the electric field reduce the growth rate considerably compared to a non-conducting fluid in the absence of an electric field. These are favorable to control the surface...
2011-01-01
Effect of material aging on parachute pack life: a synopsis of Sandia National Laboratories studies
Energy Technology Data Exchange (ETDEWEB)
A systematic study of the effects of environmental factors on nylon 66 and Kevlar 29 strength degradation in parachute components is being conducted at Sandia National Laboratories. It includes: (1) accelerated aging studies in air, inert environments, humidity, ozone, and smog; (2) a 25-year surveillance program of parachutes in a variety of natural climatic environments; (3) moisture absorption as a function of humidity; (4) effects of surface coatings normally applied to parachutes; and (5) development of nondestructive evaluation techniques which can be used to map mechanical properties over the entire parachute surface. The accelerated aging and moisture absorption studies show that air, humidity, and smog contribute to degradation. Chemiluminescence, gas chromatographic pyrograms, and uv spectroscopy show promise as nondestructive evaluation techniques.
1984-01-01
British Library Electronic Table of Contents (United Kingdom)
A study was undertaken to assess the effect of different storage temperatures on senescence and postharvest performance of isolated flowers of Ranunculus asiaticus L.. The main aim of the work was to develop a cost-effective storage protocol to reduce the postharvest losses and to bring out the transportation of cut flowers of R. Asiaticus. The flowers were subjected to two different storage treatments, dry storage and wet storage, and their postharvest performance was compared under laboratory conditions. For this purpose, the buds were harvested at 8:00 AM at loose bud stage (Stage II of flower development). The harvested buds were cut to a uniform size of 15 cm and processed for dry or wet storage. For dry storage, the buds were packed after wrapping them in moistened filter papers and ...
2011-01-01
International Nuclear Information System (INIS)
Tricking filters are a very promising alternative for the post treatment of effluents from UASB reactors treating domestic sewage,especially in developing countries. Although a fair amount of information is already available regarding organic mater removal in this combined system, very little is known in relation to nitrogen and surfactant removal in trickling filters post-UASB reactors. Therefore, the purpose of this study was to evaluate and compare the effect evaluate and compare the effect of different application rates and packing media types on trickling filters applied to the post-treatment of effluents from UASB reactors, regarding the removal of ammonia nitrogen and surfactants. (Author)
Effect of alloying on the phase transformations and properties of a nickel alloy
Energy Technology Data Exchange (ETDEWEB)
The phase transformations and properties of a precipitation-hardened Ni-Cr-based alloy are investigated as a function of C, B, Nb, and Cr contents. It is found that the primary role of Nb consists in the formation of an independent phase, delta-Ni3Nb, a part of a gamma/gamma-prime-delta eutectoid (for high C and B concentrations) and in stimulating the gamma-sigma reaction consecutively with the gamma double prime-delta reaction (for low C and B concentrations). In both cases, the long-term strength characteristics of the Nb-alloyed system are relatively low. The substitution of boron for carbon contributes to a reduction in the number of nucleation sites for topologically close-packed phases and to the formation of more stable (with respect to excess compounds) M3B2 and MB2 borides. The high-boron material exhibits better properties and phase stability under mechanical and thermal loading. 13 references.
1986-07-01
Duplex surface treatment of AISI 1045 steel via plasma nitriding of chromized layer
British Library Electronic Table of Contents (United Kingdom)
In this work AISI 1045 steel were duplex treated via plasma nitriding of chromized layer. Samples were pack chromized by using a powder mixture consisting of ferrochromium, ammonium chloride and alumina at 1273K for 5h. The samples were then plasma-nitrided for 5h at 803K and 823K, in a gas mixture of 75%N2+25%H2. The treated specimens were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis and Vickers micro-hardness test. The thickness of chromized layer before nitriding was about 8mm and it was increased after plasma nitriding. According to XRD analysis, the chromized layer was composed of chromium and iron carbides. Plasma nitriding of chromized layer resulted in the formation of chromium and iron nitrides and carbides. The hardness of the duplex layer...
2011-01-01
Distribution of Fuel-Grade Ethanol near a Dynamic Water Table
British Library Electronic Table of Contents (United Kingdom)
Injections of fuel-grade ethanol (95% v/v ethanol, 5% v/v hydrocarbon mixture as a denaturant) near the water table were conducted in two-dimensional physical models tightly packed with fine sands under varying water-table conditions. As the fuel migrated in the porous media following injection, the denaturant phase separated leaving a residual Light Non-Aqueous Phase Liquid (LNAPL) phase that occupied a region with a volume similar to that of an equal-sized spill of 100% LNAPL without ethanol. When the water table was raised, as may be expected following a catastrophic release that reaches groundwater, most of the ethanol-fuel mixture was mobilized and the vertical distribution of the generated LNAPL was increased. The lower boundary of the residual LNAPL was established during the initia...
2011-01-01
Development of the Weapon Borne Sensor parachute system
Energy Technology Data Exchange (ETDEWEB)
A parachute system was designed and prototypes built to deploy a telemetry package behind an earth-penetrating weapon just before impact. The parachute was designed to slow the 10 lb. telemetry package and wire connecting it to the penetrator to 50 fps before impact occurred. The parachute system was designed to utilize a 1.3-ft-dia cross pilot parachute and a 10.8-ft-dia main parachute. A computer code normally used to model the deployment of suspension lines from a packed parachute system was modified to model the deployment of wire from the weapon forebody. Results of the design calculations are presented. Two flight tests of the WBS were conducted, but initiation of parachute deployment did not occur in either of the tests due to difficulties with other components. Thus, the trajectory calculations could not be verified with data. Draft drawings of the major components of the parachute system are presented.
1998-06-01
Development of fluidized bed cement sintering technology
Energy Technology Data Exchange (ETDEWEB)
In the new system presented in this paper, the cement clinker is sintered, not in a rotary kiln, but in two different furnaces: a spouted bed kiln and a fluidized bed kiln. The heat generated in the process of cooling the cement clinker is recovered by a fluidized bed cooler and a packed bed cooler, which are more efficient than the conventional coolers. Compared with the rotary kiln system, the new technology significantly reduces NO{sub x} emissions, appreciably cuts energy consumption, and reduces CO{sub 2} emissions as well. Thus, the new system is an efficient cement sintering system that is friendly to the global environment. In this paper, we describe this new technology as one of the applied technologies at an industrial level that is being developed in the Clean Coal Technology Project, and we present the results from test operations at our pilot plant.
1994-12-31
Design and mass transfer characteristics of rotating screw brush horizontal distillation column
Energy Technology Data Exchange (ETDEWEB)
A distillation column with an adjustable slope horizontal rectification section was constructed. A rotating screw brush was inserted into the section, which could be rotated from 0 to 600 rpm with an external motor. Distillation experiments were carried out using the system cyclohexane-heptane at total reflux at slopes of 0(horizontal), 5 and 10 degrees. Separation efficiency for the horizontal column was the highest of the three orientations, and was obtained as HETP from 0.04 to 0.16 m at F-factor of 0.05 to 0.4 m/s(kg/m{sup 3}){sup 1/2} in the range of 100 to 600 rpm. The HETP for each slope was roughly constant at a rotation speed of more than 300 rpm. The values of the pressure drop were found to be equivalent to those of one seventh to one fifth of conventional packed columns. (author)
2000-10-01
Communication Estimation for Hardware/Software Codesign
DEFF Research Database (Denmark)
This paper presents a general high level estimation model of communication throughput for the implementation of a given communication protocol. The model, which is part of a larger model that includes component price, software driver object code size and hardware driver area, is intended to be general enough to be able to capture the characteristics of a wide range of communication protocols and yet to be sufficiently detailed as to allow the designer or design tool to efficiently explore tradeoffs between throughput, bus widths, burst/non-burst transfers and data packing strategies. Thus it provides a basis for decision making with respect to communication protocols/components and communication driver design in the initial design space exploration phase of a co-synthesis process where a large number of possibilities must be examined and where fast estimators are therefore necessary. The fill model allows for additional (money) cost, software code size and hardware ...
1998-01-01
Chemical and physical change of packaging materials for food by gamma-ray irradiation
International Nuclear Information System (INIS)
Recently, foods are often exposed to radiation under packed states with various wrapping materials. In this study, the effects of #gamma#-ray radiation were investigated on the additives in wrapping materials on the market. 10 - 50 kGy #gamma# radiation was irradiated to samples under sealed condition in a glass-ware. Polyethylene bag and wrapping film, polypropylene wrapping film, cup and sheet, and polystyrene cup were used as samples. And the additives in these materials were analyzed by GC/MS to evaluate the radiation effects on them. The irradiation was found to induce rapid degradation of antioxidants, especially, Irgafos 168. Some fatty acid amides used as a lubricant and a plasticizer, DBP were also reduced, but not aliphatic hydrocarbons. However, all polystyrene products used in this study included no additives. The contents of styrene dimer and trimer in those wrapping materials were not changed by #gamma#-irradiation. (M.N.)
1999-02-01
Energy Technology Data Exchange (ETDEWEB)
This paper describes the development and testing of a system to provide isolated power to the cathode-subsystem electronics of an x-ray tube. These components are located at the cathode potential of several hundred kilovolts, requiring a supply of power isolated from this high voltage. In this design a fiber-optically connected photonic power system (PPS) is used to recharge a lithium-ion battery pack, which will subsequently supply power to the cathode-subsystem electronics. The suitability of the commercially available JDSU PPS for this application is evaluated. The output of the ppe converter is characterized. The technical aspects of its use for charging a variety of Li-Ion batteries are discussed. Battery charge protection requirements and safety concerns are also addressed.
2008-01-01
Catalytic tar removal from biomass producer gas with secondary air
Energy Technology Data Exchange (ETDEWEB)
The effect of air addition on biomass tar conversion in catalytic packed bed crackers was studied using both an isothermal micro reactor and a fluidised bed bench scale biomass gasification set up with down stream tar crackers. The micro reactor was applied for experiments with artificial biomass producer gas containing naphthalene as a model tar compound. Experiments were carried out with inert silica and catalytically active calcined dolomite bed material both with and without air addition. Experimental results with real tar from the fluidised bed bench scale gasification set up were in qualitative agreement with results from the micro reactor experiments. (author)
1997-12-31
Aquaculture of Uranium in Seawater by a Fabric-Adsorbent Submerged System
The total amount of uranium dissolved in seawater at a uniform concentration of 3 mg U/m{sup 3} in the world's oceans is 4.5 billion tons. An adsorption method using polymeric adsorbents capable of specifically recovering uranium from seawater is reported to be economically feasible. A uranium-specific nonwoven fabric was used as the adsorbent packed in an adsorption cage 16 m{sup 2} in cross-sectional area and 16 cm in height. We submerged three adsorption cages in the Pacific Ocean at a depth of 20 m at 7 km offshore of Japan. The three adsorption cages consisted of stacks of 52 000 sheets of the uranium-specific non-woven fabric with a total mass of 350 kg. The total amount of uranium recovered by the nonwoven fabric was >1 kg in terms of yellow cake during a total submersion time of 240 days in the ocean.
2003-11-15
Aquaculture of Uranium in Seawater by a Fabric-Adsorbent Submerged System
International Nuclear Information System (INIS)
The total amount of uranium dissolved in seawater at a uniform concentration of 3 mg U/m3 in the world's oceans is 4.5 billion tons. An adsorption method using polymeric adsorbents capable of specifically recovering uranium from seawater is reported to be economically feasible. A uranium-specific nonwoven fabric was used as the adsorbent packed in an adsorption cage 16 m2 in cross-sectional area and 16 cm in height. We submerged three adsorption cages in the Pacific Ocean at a depth of 20 m at 7 km offshore of Japan. The three adsorption cages consisted of stacks of 52 000 sheets of the uranium-specific non-woven fabric with a total mass of 350 kg. The total amount of uranium recovered by the nonwoven fabric was >1 kg in terms of yellow cake during a total submersion time of 240 days in the ocean.
2003-11-01
British Library Electronic Table of Contents (United Kingdom)
This study investigated the optimum polyphenol extraction conditions for two Nigerian green leafy vegetables, Vernonia amygdalina (VA) and Gongronema latifolium (GL) that are widely used for food and medicinal purposes. Seven different solvents were used to extract the total phenolic contents of the leaves; 100% acetone, 80% acetone, 50% acetone, 100% ethanol, 70% ethanol, 100% methanol and 70% methanol and their total phenolic contents were determined. The results showed that the 80% acetone was significantly (p<0.05) the most effective for polyphenol extraction from the leaves and generally the acetone-containing solvents were more effective than alcohol-containing solvents. The 80% acetone extract was fractionated on a silicic acid-packed column to give two main fractions: acetone elute...
2011-01-01
Advanced resin cleaning system
International Nuclear Information System (INIS)
Novel and unprecedented ion exchange resin cleaning system, for use in BWR plants and featuring a vibration separator and basic design factors of Radiological Solutions, Inc., had been delivered to Tokai No. 2 Power Station, Japan Atomic Power Company, in October 2005. This compactly-designed system effectively separates crud and resin fines from ion exchange resins, with no clogging of separation screens. It generates minimized waste liquid and has a specially designed over-pack cleaning tank. The system has been in operation for about 2 years and half now and favorable operational data, such as crud and sulfate concentration decrease in feed water and reactor water respectively, and evaluation results have been reported from Japan Atomic Power Company and so on. (author)
2008-07-01
Adsorption of Pb^2^+ and Zn^2^+ from aqueous solutions by sulfured orange peel
British Library Electronic Table of Contents (United Kingdom)
In this study, sulfured orange peel (MOP) was used as adsorbent to investigate its adsorption behaviors of Pb^2^+ and Zn^2^+ from aqueous solutions. The effects of solution pH, adsorption time and metal ion concentration on adsorption were studied in batch experiments. Both adsorption kinetics of Pb^2^+ and Zn^2^+ proceeded rapidly and could be well described by pesudo-second-order equation. The maximum Langmuir adsorption capacities for Pb^2^+ and Zn^2^+ removal by MOP were evaluated as 164 and 80mg/g, respectively. A binary mixture of Pb^2^+ and Zn^2^+ was studied by using a packed column, suggesting that effective mutual separation and pre-concentration of Pb^2^+ away from Zn^2^+ using MOP could be satisfactory achieved. The results indicate that MOP could be employed as an effective lo...
2011-01-01
Adsorption and Dissociation of Molecular Hydrogen on the (0001) Surface of DHCP Americium
Hydrogen molecule adsorption on the (0001) surface of double hexagonal closed packed americium has been studied in detail within the framework of density functional theory. Weak molecular hydrogen adsorptions were observed. The most stable configuration corresponded to a Hor2 approach molecular adsorption at the one-fold top site where the molecule's approach is perpendicular to a lattice vector. Adsorption energies and adsorption geometries for different adsorption sites will be discussed. The change in work functions, magnetic moments, partial charges inside muffin-tins, difference charge density distributions and density of states for the bare Am slab and the Am slab after adsorption of the hydrogen molecule will be discussed. Reaction barrier for the dissociation of hydrogen molecule will be presented. The implications of adsorption on Am 5f electron localization-delocalization will be summarized.
2009-03-01
Energy Technology Data Exchange (ETDEWEB)
The authors describe a small doubly reflecting research furnace. Its optical components, a heliostat and a concentrating array of hexagonal-in-plan-form mirrors, focus sunlight at the aperture of a cavity receiver. A perfect paraboloid of revolution would have given higher concentration ratios. But large paraboloids are difficult to make and manipulate. Small hexagons are convenient and can be close packed. Spherical mirrors centered on a sphere simplified construction and were economical. In this note they use a simple model to describe the radial distribution of the normal flux at the focus of such an array. A schematic representation of a cross section of the concentrator mirror array in a plane which includes its axis is shown.
1984-02-01
A ZnO nanowire array film with stable highly water-repellent properties
Energy Technology Data Exchange (ETDEWEB)
Highly water-repellent surfaces have been prepared from arrayed nanowires of zinc oxide (ZnO) by a treatment with stearic acid. The layers are electrochemically deposited on a nanocrystalline seed layer from an oxygenated aqueous zinc chloride solution. An advancing contact angle (CA) as high as 176{sup 0} is obtained with a very small hysteresis {approx}1{sup 0}. These results, supplemented by infrared spectroscopy, show that the stearic acid forms a very well-packed self-assembled monolayer. The CA measurements show a very good stability of the treated surface even when exposed to harsh conditions or long-term ambient illumination.
2007-09-12
Wire pad chamber for LHCb muon system
2000-003 Wire pad chambers (WPC) have been proposed for the outer Region 4 of the LHCb Muon System. These are double gap MWPCs with small wire spacing allowing to obtain 99% detection efficiency in a 20 ns time window. The chambers have a rectangular shape with the vertical dimension from 20 cm in Station 1 to 30 cm in Station 5. The horizontal dimensions will be different with the maximal size of 3 meters in Station 5. The wires are in the vertical direction. The short wire length allows to use small wire spacing needed for high time resolution. Also, this helps to obtain the uniform gas gain over the whole chamber area. The WPC has one row of the wire pads formed by grouping wires in separate readout channels. Four WPC prototypes have been built at PNPI and tested in the PS beam at CERN. Here we report on the results from these tests. Also, the results of simulation of the WPC performance are presented.
2000-01-01
Tune resonance phenomena in the SPS and machine protection via fast position interlocking
Energy Technology Data Exchange (ETDEWEB)
The 6911 m long Super Proton Synchrotron (SPS) at CERN with a peak energy of 450 GeV is at the top of the LHC preaccelerator-complex. Apart from the LHC, the SPS is with the Tevatron the accelerator with the largest stored beam energy of up to 2.5 MJ. The SPS has a known vulnerability to fast equipment failures that led to an uncontrolled loss of a high intensity beam in 2008, which resulted in major damage of a main dipole. The beam loss was caused by a fast tune decrease towards an integer resonance. Simulations and distinct experimental studies provide clear understanding of the beam dynamics at different SPS tune resonances. Diverging closed orbit oscillations, dispersion explosion and increased beta-beating are the driving effects that lead to a complete beam loss in as little as 10 turns (230 {mu}s) after reaching the stop band of the resonance. Dedicated experiments of fast failures of the main power converters reveal that the current interlock systems with ...
2010-07-01
Tune resonance phenomena in the SPS and machine protection via fast position interlocking
International Nuclear Information System (INIS)
The 6911 m long Super Proton Synchrotron (SPS) at CERN with a peak energy of 450 GeV is at the top of the LHC preaccelerator-complex. Apart from the LHC, the SPS is with the Tevatron the accelerator with the largest stored beam energy of up to 2.5 MJ. The SPS has a known vulnerability to fast equipment failures that led to an uncontrolled loss of a high intensity beam in 2008, which resulted in major damage of a main dipole. The beam loss was caused by a fast tune decrease towards an integer resonance. Simulations and distinct experimental studies provide clear understanding of the beam dynamics at different SPS tune resonances. Diverging closed orbit oscillations, dispersion explosion and increased beta-beating are the driving effects that lead to a complete beam loss in as little as 10 turns (230 #mu#s) after reaching the stop band of the resonance. Dedicated experiments of fast failures of the main power converters reveal that the current interlock systems with ...
2010-03-15
The SysMES framework: System management for networked embedded systems and clusters
Energy Technology Data Exchange (ETDEWEB)
The ALICE heavy-ion particle physics experiment is currently being built at CERN near Geneva. It will use a PC cluster of 900 dual-processor machines for the last stages of the data readout process and a network of 400 microcomputers for the configuration and control of the cluster nodes. One of the most important objectives to be achieved in such experiments is to guarantee the utilized devices are running correctly during the experiment life-time. A second aspect is the extremely high availability and reliability requirements of the applications being run, the so called high level trigger (HLT). The SysMES framework is a scalable, decentralized, fault tolerant, dynamic, rule based tool set for the monitoring of networks of target systems and applications. The management algorithms consist of the following steps: system and application monitoring, recognition of undesirable states, event (message) generation, local event handling on the target, event forwarding to ...
2008-07-01
Strong-field quantum-electrodynamic processes in aligned crystals
Energy Technology Data Exchange (ETDEWEB)
When a highly collimated beam of particles is aimed along the atomic rows of an aligned single crystal, the averaging effect of high speed motion results, to the lowest order of approximation, in crystal electric fields which are transverse to the atomic rows. The enormous magnitude of the crystal transverse electric fields is unsurpassed by any other known earth-bound macroscopic sources. For example, the field strengths along the <100> axis of tungsten at 77 K approach 9{center dot}10{sup 13}V/m. Thus quantum electrodynamic (QED) processes in strong fields which are thought to occur only in the extra-terrestrial environment can now be investigated in the laboratory. Here we review the results of measurements performed at the SPS facility in CERN using highly collimated beams of electrons, positrons and photons in the 20-200 GeV range, and germanium crystals cooled to 77 K with thicknesses ranging from 0.07 mm to 1.40 mm. The focus is on the simplest ...
1989-01-01
Ranking Scientific Publications Based on Their Citation Graph
CDS Invenio is the web-based integrated digital library system developed at CERN. It is a suite of applications which provides the framework and tools for building and managing an autonomous digital library server. Within this framework, the goal of this project is to implement new ranking methods based on the bibliographic citation graph extracted from the CDS Invenio database. As a first step, we implemented the Citation Count as a baseline ranking method. The major disadvantage of this method is that all citations are treated equally, disregarding their importance and their publication date. To overcome this drawback, we consider two different approaches: a link-based approach which extends the PageRank model to the bibliographic citation graph and a time-dependent approach which takes into account time in the citation counts. In addition, we also combined these two approaches in a hybrid model based on a time-dependent PageRank. In the present document, we ...
2009-01-01
Proposal for a High Energy Nuclear Database
Energy Technology Data Exchange (ETDEWEB)
The authors propose to develop a high-energy heavy-ion experimental database and make it accessible to the scientific community through an on-line interface. This database will be searchable and cross-indexed with relevant publications, including published detector descriptions. Since this database will be a community resource, it requires the high-energy nuclear physics community's financial and manpower support. This database should eventually contain all published data from Bevalac, AGS and SPS to RHIC and CERN-LHC energies, proton-proton to nucleus-nucleus collisions as well as other relevant systems, and all measured observables. Such a database would have tremendous scientific payoff as it makes systematic studies easier and allows simpler benchmarking of theoretical models to a broad range of old and new experiments. Furthermore, there is a growing need for compilations of high-energy nuclear data for applications including stockpile stewardship, ...
2005-03-31
Procedure for obtaining visas for Switzerland and France - Signature rights
In accordance with the Status Agreements with CERN, Switzerland and France facilitate the entry of members of the Organization’s personnel onto their territories. Where relevant, detailed procedures for obtaining visas apply. Within the framework of those procedures, only the following individuals are authorised to initiate the Note verbale procedure as well as to sign the Official Invitation Letters and the Protocoles d’accueil. Kirsti ASPOLA (PH – CMO) Oliver BRÜNING (BE – ABP) Michelle CONNOR (PH – AGS) Sylvie DETHURENS FAVEZ (HR – SPS) David FOSTER (IT – DI) Nathalie GRUB (PH – AGS) Tadeusz KURTYKA (DG – PRJ) Jean-Pol MATHEYS (BE – ASR) Cécile NOELS (DG – PRJ) Connie POTTER (PH – AGS) Maria QUINTAS (HR – SPS) Jeanne ROSTANT (PH – AGS) ...
2010-01-01
Online processing in the ALICE DAQ The detector algorithms
ALICE (A Large Ion Collider Experiment) is the heavy-ion detector designed to study the physics of strongly interacting matter and the quark-gluon plasma at the CERN Large Hadron Collider (LHC). Some specific calibration tasks are performed regularly for each of the 18 ALICE sub-detectors in order to achieve most accurate physics measurements. These procedures involve events analysis in a wide range of experimental conditions, implicating various trigger types, data throughputs, electronics settings, and algorithms, both during short sub-detector standalone runs and long global physics runs. A framework was designed to collect statistics and compute some of the calibration parameters directly online, using resources of the Data Acquisition System (DAQ), and benefiting from its inherent parallel architecture to process events. This system has been used at the experimental area for one year, and includes more than 30 calibration routines in production. This paper ...
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
The LHCb experiment that is being settled in CERN is dedicated to the study of CP violation and rare decays in the field of beauty hadrons. The phenomenological background necessary to an adequate understanding of the physics of flavor is presented in the first chapter, it is shown how the flavordynamics can open the way to new physics. The second chapter is dedicated to a brief presentation of the LHCb detector. Two aspects of the design of the muon trigger are more detailed: the radiation resistance of the opto-electronic transmitters and the simulated performances of the trigger. The third chapter reviews the tasks linked to the tagging of the savors of B mesons which will be an important step in all the experiments made at LHCb. The recent progress in heavy savor physics as well as the expected contribution of LHCb in this field are presented in the fourth chapter, especially the search for new physics in penguin diagrams b {yields} s.
2007-10-15
International Nuclear Information System (INIS)
Angelin Pedra is a specie found in the north of Mato Grosso State in Brazil, where an expressive volume of waste of this wood is produced. An alternative to recycle this waste is to produce wood plastic composites. However, structural and chemical investigations are fundamental to generate information for this use. In the present work, low field NMR was used to determine the spin-lattice and spin-spin relaxation times with objective to investigate the molecular dynamic behavior of the alburnu and cerne regions of Angelin Pedra aiming at a potential use of this waste wood in polymeric composites. The results of the proton spin-lattice relaxation time (T1H) and the proton spin-spin relaxation time (T2H) showed at least three different mobility domains for both regions. Among the values, one was very flexible and other was rigid. Knowing that wood is a polymer composite basically constituted by cellulose, hemicellulose and lignin can attribute the smaller T1 value and ...
2005-11-06
Ion sources for initial use at the Holifield radioactive ion beam facility
Energy Technology Data Exchange (ETDEWEB)
The Holifield Radioactive Ion Beam Facility (HRIBF) now under construction at the Oak Ridge National Laboratory will use the 25-MV tandem accelerator for the acceleration of radioactive ion beams to energies appropriate for research in nuclear physics; negative ion beams are, therefore, required for injection into the tandem accelerator. Because charge exchange is an efficient means for converting initially positive ion beams to negative ion beams, both positive and negative ion sources are viable options for use at the facility; the choice of the type of ion source will depend on the overall efficiency for generating the radioactive species of interest. A high-temperature version of the CERN-ISOLDE positive ion source has been selected and a modified version of the source designed and fabricated for initial use at the HRIBF because of its low emittance, relatively high ionization efficiencies and species versatility, and because it has been engineered for remote ...
1994-12-31
Ion sources for initial use at the Holifield Radioactive Ion Beam Facility
Energy Technology Data Exchange (ETDEWEB)
The Holifield Radioactive Ion Beam Facility (HRIBF) now under construction at the Oak Ridge National Laboratory will use the 25-MV tandem accelerator for the acceleration of radioactive ion beams to energies appropriate for research in nuclear physics; negative ion beams are, therefore, required for injection into the tandem accelerator. Because charge exchange is an efficient means for converting initially positive ion beams to negative ion beams, both positive and negative ion sources are viable options for use at the facility; the choice of the type of ion source will depend on the overall efficiency for generating the radioactive species of interest. A high-temperature version of the CERN-ISOLDE positive ion source has been selected and a modified version of the source designed and fabricated for initial use at the HRIBF because of its low emittance, relatively high ionization efficiencies and species versatility, and because it has been engineered for remote ...
1994-05-01
Front-End-Electronics Communication software for multiple detectors in the ALICE experiment
Energy Technology Data Exchange (ETDEWEB)
In the ALICE experiment at CERN, the Detector Control System (DCS) employs several interacting software components to accomplish its task of ensuring the correct operation and monitoring of the experiment. This paper describes the Front-End-Electronics Communication (FeeCommunication) software and its role within the DCS. The FeeCommunication software's central task is passing configuration and monitoring data between the top level DCS process control and the field devices of several detectors within ALICE. The lowest level of the FeeCommunication software runs on the DCS boards, specialized embedded systems which are in direct contact with the field devices and are physically located within the detector. The middle and upper layers run on standard PC hardware located in the counting room or other external locations. This paper focuses on the design and implementation of the FeeCommunication software and the steps that were taken to fulfill the imposed ...
2006-02-15
European facilities for accelerator neutrino physics: perspectives for the decade to come
Very soon a new generation of reactor and accelerator neutrino oscillation experiments - Double Chooz, Daya Bay, Reno and T2K - will seek for oscillation signals generated by the mixing parameter theta_13. The knowledge of this angle is a fundamental milestone to optimize further experiments aimed at detecting CP violation in the neutrino sector. Leptonic CP violation is a key phenomenon that has profound implications in particle physics and cosmology but it is clearly out of reach for the aforementioned experiments. Since late 90's, a world-wide activity is in progress to design facilities that can access CP violation in neutrino oscillation and perform high precision measurements of the lepton counterpart of the Cabibbo-Kobayashi-Maskawa matrix. In this paper the status of these studies will be summarized, focusing on the options that are best suited to exploit existing European facilities (firstly CERN and the INFN Gran Sasso Laboratories) or technologies where ...
2009-01-01
Energy Technology Data Exchange (ETDEWEB)
Yet designed to measure charged component of the cosmic rays, the foreseen Alpha Magnetic Spectrometer (AMS-02) could also release {gamma}-ray studies, in the energy range from GeV to TeV, using the tracker system, for {gamma}-rays converted in e{sup +}e{sup -} pair, and the electromagnetic calorimeter. In the first part of the thesis are described the calibrations and the performances of the engineering model of the calorimeter, obtained from the analysis of data taken during a test-beam performed at CERN in July 2002. In the second part of the thesis, the AMS-02 discovery potential for {gamma}-astrophysics is presented. While exposure maps of the {gamma}--sky are computed for one year of data taking with the {gamma}--detectors, the acceptance of the calorimeter is obtained from Monte-Carlo simulations. The AMS-02 potential is then estimated for signals from the Vela pulsar and for some supersymmetric signals from the Galactic Center. (author)
2004-12-15
Construction and Calibration of the Laser Alignment System for the CMS Tracker
The CMS detector (Compact Muon Solenoid) is under construction at one of the four proton-proton interaction points of the LHC (Large Hadron Collider) at CERN, the European Organization for Nuclear Research (Geneva, Switzerland). The inner tracking system of the CMS experiment consisting of silicon detectors will have a diameter of 2.4 m and a length of 5.4 m representing the largest silicon tracker ever. About 15000 silicon strip modules create an active silicon area of 200 m2 to detect charged particles from proton collisions. They are placed on a rigid carbon fibre structure, providing stability within the working conditions of a 4 T solenoid magnetic field at ?10oC. Knowledge of the position of the silicon detectors at the level of 100 ?m is needed for an efficient pattern recognition of charged particle tracks. Metrology methods are used to survey tracker subdetectors and the integrated Laser Alignment System (LAS) provides absolute positioning of support ...
2006-01-01
CHANGE@CERN:Task Force 5 : Restructuring the accelerator sector
The last of our series on the Task Forces. PS accelerator 'We had a clear mandate, which we could approach in a logical way', explains Steve Myers, Head of SL Division and convenor of Task Force 5, 'To avoid duplication of effort in the accelerator sector through a restructuring that would lead to greater efficiency and flexibility and so release resources for the LHC.' The implementation of all their recommendations is already underway, albeit with different time scales. In 2001 the accelerator sector involved more than 900 staff members in three divisions (LHC, PS and SL) and one unit (AC), working in 141 sections within 34 groups. The first step for the Task Force was to identify major activities within the sector and to set up inter-divisional working groups to review these activities (16 in all), identifying the technologies and the numbers of staff associated with each activity. The working groups were also asked to propose ways of grouping the activities into a new more ...
2002-01-01
B#->##tau#"+#tau#"-(X) decays: First constraints and phenomenological implications
International Nuclear Information System (INIS)
The study of B#->##tau#"+#tau#"-(X) decays can provide us with a better understanding of the third generation, and can be a useful probe of physics beyond the standard model. We present a model-independent analysis of these decays. We classify new physics that can largely enhance the decay rates and we discuss the constraints implied by other processes. Experimentally, flavor-changing neutral current B decays into final state #tau# close-quote s are still unconstrained. Searches for B decays with large missing energy at CERN LEP provide the first limits. We estimate that existing data already imply bounds on the B_d#->##tau#"+#tau#"-, B_s#->##tau#"+#tau#"-, and B#->#X#tau#"+#tau#"- decay rates at the few percent level. Although these bounds are over four orders of magnitude above the standard model predictions, they provide the first constraints on some leptoquarks, and on some R-parity-violating couplings. copyright 1997 The American Physical Society.
International Nuclear Information System (INIS)
Research and development and other activities of the various constituent units of Department of Atomic Energy (DAE) and also of the institution aided by DAE for the year 2005-2006 are reported. The various constituents units of DAE consist of nuclear research centres, nuclear power stations, fuel reprocessing and heavy water plants, nuclear fuel fabrication facilities, electronic and instrumentation production organisations, atomic mineral processing units and other nuclear installations. The activities of DAE cover the whole gamut of nuclear fuel cycle, research and development in nuclear science and reactor technology, applications of radiation and radioisotopes, radiation protection, research and development in front line areas such as robotics, lasers, mathematics and computational sciences. International research collaborations like CERN-DAE collaboration were completed by BARC. These activities are described broadly under: executive summary, nuclear power ...
A Pedagogical Review of Electroweak Symmetry Breaking Scenarios
The aim of this set of lectures is to review different avenues of electroweak symmetry breaking explored over the years. This constitutes a timely exercise as the world's largest and the highest energy particle accelerator, namely, the Large Hadron Collider (LHC) at CERN near Geneva, is all set to start running whose primary mission is to unravel the mysteries of electroweak phase transition. In the beginning, we discuss the Standard Model Higgs mechanism. After that we review the Higgs sector of the Minimal Supersymmetric Standard Model. Then we take up three relatively recent ideas: Little Higgs, Gauge-Higgs Unification, and Higgsless scenarios. For the latter three cases, we present the basic ideas and restrict our illustrations to some instructive toy models, as our intention is rather to provide an intuitive feel of the underlying dynamics than to get into an in-depth analysis of realistic scenarios. Wherever possible, we provide enough pedagogical details, ...
2009-01-01
2001 Report on the Next Linear Collider
Energy Technology Data Exchange (ETDEWEB)
Recent studies in elementary particle physics have made the need for an e{sup +}e{sup -} linear collider able to reach energies of 500 GeV and above with high luminosity more compelling than ever [1]. Observations and measurements completed in the last five years at the SLC (SLAC), LEP (CERN), and the Tevatron (FNAL) can be explained only by the existence of at least one particle or interaction that has not yet been directly observed in experiment. The Higgs boson of the Standard Model could be that particle. The data point strongly to a mass for the Higgs boson that is just beyond the reach of existing colliders. This brings great urgency and excitement to the potential for discovery at the upgraded Tevatron early in this decade, and almost assures that later experiments at the LHC will find new physics. But the next generation of experiments to be mounted by the world-wide particle physics community must not only find this new physics, they must find out what it ...
2001-08-28
Xebra electric vehicle. Case study, ZAP - USA; Lithium-ion battery
Energy Technology Data Exchange (ETDEWEB)
The Zap Xebra Electric Truck is fitted with 23 Li-Ion Cells from China providing a nominal voltage of 72V and a nominal capacity of 400AH. The Li-Ion cells weighing 13 kg each, making the total weight of the battery pack approx. 300 kg. A Battery Management System (BMS) from Lithium Balance is installed to ensure safe, reliable and maximum performance of the batteries. The testing of the Zap Xebra Electric Truck included two kinds of test, a Stop-and-Go test and a range test. Our Stop-and-Go test consists of accelerating the vehicle for 1 km (0.62mi), braking and then accelerate for 1 km(0.62mi), counting the number of stop-and-goes. Our range test is a real-world test including stops, accelerations, driving in the city and in the countryside, going uphill and downhill. This test shows the average range that the end user will experience. Looking at the results of both the tests and comparing them with the data of a Xebra with Pb-acid batteries, we can conclude that ...
2008-07-01
Treatment for dismantled radioactive solid waste from the TRIGA Mark-2 and 3
Energy Technology Data Exchange (ETDEWEB)
Radioactive wastes are generally classified into 3 type depending on their physical property: liquid, solid and gaseous type. State-of -the art concerning liquid waste treatment has already been published; KAERI/TR-1315/99. Solid wastes classification package and treatment method will be studied to effectively manage them during the practical decommissioning work. All of the spent fuel produced during the operation of the TRIGA Mark-2 and 3 have been transported to the US last year, 1998, according to the spent fuel management strategy set-up by the US government for the non-proliferation of nuclear energy. Solid wastes are mainly all equipment existing inside of the reactors, activated concrete among the bio-shielded concrete, pipes, pimps, resin filter and it's housings, heat-exchangers, liquid waste storage tanks, to radioactive waste storage treatment facilities and so on. Solid wastes are generally low-level. They are classified according to the national regulation and ...
1999-06-01
Energy Technology Data Exchange (ETDEWEB)
Fuel irradiation leads to a swelling resulting from the formation of gaseous (Kr, Xe) or solid fission products which are found either in solution or as solid inclusions in the matrix. This phenomena has to be evaluated to be taken into account in fuel cladding Interaction. Fuel swelling was studied as a function of burn up by measuring the corresponding cell constant evolution by X-Ray diffraction. This study was realized on Mixed Oxide Fuels (MOX) irradiated in a Pressurized Water Reactor (PWR) at different burn-up for 3 initial Pu contents. Lattice parameter evolutions were followed as a function of burn-up for the irradiated fuel with and without an annealing thermal treatment. These experimental evolutions are compared to the theoretical evolutions calculated from the hard sphere model, using the fission product concentrations determined by the APPOLO computer code. Contribution of varying parameters influencing the unit cell value is discussed. Thermal treatment effects were ...
1995-07-01
Energy Technology Data Exchange (ETDEWEB)
The design of separation devices, particularly for solvent-based selective removal of H{sub 2}S from CO{sub 2}, requires an accurate mathematical model. Unfortunately, this requirement for high accuracy is often in conflict with the need for efficient computation. The addition of more and more complicated analyses, such as a move from Henry's law to a method incorporating gas and liquid activities for computing vapor liquid equilibria, may give a more accurate solution, but only at the cost of decreased computational efficiency. The efforts in this work have been directed toward two goals. The first was to develop an accurate mathematical model for the aqueous methyldiethanolamine (MDEA) system. The steady-state packed column model developed in this work has been tested with data from Schubert (1988) to verify its accuracy. The second goal was to modify the model to improve its computational efficiency. Areas such as vapor-liquid equilibrium calculations, ...
1988-01-01
International Nuclear Information System (INIS)
Studies were made on different types of packaging materials used for packing dried fish in the Philippines with a view to finding a suitable packaging material for irradiated dried fish. Among these packaging materials (polyethylene, cello/polyethylene, polyester/polyethylene, Kraft paper, polypropylene and interwoven polypropylene sacks), polyester/polyethylene laminate was the most resistant material against penetration by Dermestes carnivorous. No insect damage occurred on the dried fish packed in interwoven polypropylene lined with polyester/polyethylene laminate. The cost per sack of such packaging material having a capacity of 50-80 kg is US$ 0.50. The sack lined with polyester/polyethylene proved to be durable for surface transportation from Bacolod City to Manila (approx. 360 miles). Radiation treatment at 225 krad was effective against bacterial contamination but not effective in inhibiting mould growth. Raw fish soaked in 25% salt for ...
The objective of the study was the kinetic modeling of the effect of storage temperature on the quality and shelf life of chilled fish, modified atmosphere-packed (MAP), and osmotically pretreated with the addition of nisin as antimicrobial agent. Fresh gilthead seabream (Sparus aurata) fillets were osmotically treated with 50% high dextrose equivalent maltodextrin (DE 47) plus 5% NaCl. Water loss, solid gain, salt content, and water activity were monitored throughout treatment and treatment conditions were selected for the shelf life study. Untreated and osmotically pretreated slices with and without nisin (2 x 10(4) IU/100 g osmotic solution), packed in air or modified atmosphere (50% CO(2)-50% air), and stored at controlled isothermal conditions (0, 5, 10, and 15 degrees C) were studied. Quality assessment and modeling were based on growth of several microbial indices, total volatile nitrogen, trimethylamine nitrogen, lipid oxidation ...
2010-05-01
International Nuclear Information System (INIS)
A combined application of several microtechniques is presented and discussed with the Ti/TiO_2 and Zr/ZrO_2-systems as an example. All measurements were carried out on single grains of technical materials in order to detect and quantify the effect of substrate microstructure on the properties of anodic passive films formed potentiodynamically in 0.5 M H_2SO_4 (dU/dt = 20 mVs"-"1). Anisotropy-micro-ellipsometry (AME) was employed to determine the crystallographic orientation of the substrate grains along with passive film thickness and crystallinity in dependence on the anodization potential. Both the isotropic (amorphous) TiO_2- and the anisotropic (crystalline) ZrO_2-films exhibit a systematic dependence of film thickness on the grain orientation. Local LASER-scanning photocurrent measurements (#lambda#=257 nm) on the same grains likewise show a heterogeneity of the photoelectrochemical reactivity in all cases. This is quantitatively explained by the results from local electrochemical ...
1998-03-01
Low-head air stripper treats oil tanker ballast water
Energy Technology Data Exchange (ETDEWEB)
Prototype tests conducted during the winter of 1989/90 have successfully demonstrated an economical design for air stripping volatile hydrocarbons from oily tanker ballast water. The prototype air stripper, developed for Alyeska's Ballast Water Treatment (BWT) facility in Valdez, Alaska, ran continuously for three months with an average removal of 88% of the incoming volatile organics. Initially designed to remove oil and grease compounds from tanker ballast water, the BWT system has been upgraded to a three-step process to comply with new, stringent regulations. The BWT biological oxidation process enhances the growth of bacteria present in the incoming ballast water through nutrient addition, aeration, and recirculation within a complete-mixed bioreactor. The average removal of BETX is over 95%, however, occassional upsets required the placement of a polishing air stripper downstream of the aeration tanks. Packed-tower air stripping was investigated but ...
1992-02-01
Diverter/bop system and method for a bottom supported offshore drilling rig
Energy Technology Data Exchange (ETDEWEB)
A system is described adapted for alternative use as a diverter or a blowout preventer for a bottom supported drilling rig and adapted for connection to a permanent housing attached to rig structural members beneath a drilling rig rotary table, the permanent housing having an outlet connectable to a rig fluid system flow line. The system consists of: a fluid flow controller having a controller housing with a lower cylindrical opening and an upper cylindrical opening and a vertical path therebetween and a first outlet passage and a second outlet passage provided in its wall, a packing element disposed within the controller housing, and annular piston means adapted for moving from a first position to a second position, whereby in the first position the piston means wall prevents interior fluid from communicating with the outlet passages in the controller housing wall and in the second position the piston means wall allows fluid communication of interior fluid with ...
1986-07-01
Energy Technology Data Exchange (ETDEWEB)
A fast and simple flow-through optosensor was designed and characterized for the direct screening of four tetracycline (TCC) antibiotics (tetracycline, oxytetracycline, chlortetracycline and doxycycline) in water and bovine milk samples. The proposed optosensor provides rapid binary yes/no overall responses, being appropriate for the screening of this family of antibiotics above or below a pre-set concentration threshold. The experimental set-up is based on a flow-injection manifold coupled on-line to a phosphorescence detector. Aliquots of the samples are pretreated with Eu(III) to form room temperature phosphorescent metal chelates and injected in the flow manifold. Those chelates are then on-line retained on a conventional flow-cell (packed with polymeric Amberlite XAD-4 particles) which is placed inside the cell holder of the phosphorimeter. After the emission is registered, the antibiotic-metal complexes are eluted from the packed resin ...
2007-04-18
Best of the lot : engineered measurement-while-drilling tool improves efficiency of operations
Energy Technology Data Exchange (ETDEWEB)
NuEra Oilfield Services Inc. combines various technologies, including advanced bearing assemblies and compact wireless decoders that interface with downhole directional tools, to engineer unique, purpose-built measurement-while-drilling (MWD) tool string packages. The 9-metre-long MWD tool string is lowered into the drill pipe from the surface. The directional module monitors the position of the drill bit, which the driller can monitor using an electronic drilling recorder at the surface. The directional drillstring uses a mud motor with adjustable bent housing to correct the direction of the well, as the system cannot steer while drilling. At bottomhole, mud circulation continues after the rotation of the drillstring has been stopped, driving the mud motor, which in turn drives the drill bit, permitting a new direction to be taken even though the drillstring is not turning. The operator points the bent housing in a new direction and slides the bit along before restarting the rotation ...
2010-10-15
The performance of intermolecular potential models on the adsorption of carbon tetrachloride on graphitized thermal carbon black at various temperatures is investigated. This is made possible with the extensive experimental data of Machin and Ross(1), Avgul et al.,(2) and Pierce(3) that cover a wide range of temperatures. The description of all experimental data is only possible with the allowance for the surface mediation. If this were ignored, the grand canonical Monte Carlo (GCMC) simulation results would predict a two-dimensional (2D) transition even at high temperatures, while experimental data shows gradual change in adsorption density with pressure. In general, we find that the intermolecular interaction has to be reduced by 4% whenever particles are within the first layer close to the surface. We also find that this degree of surface mediation is independent of temperature. To understand the packing of carbon tetrachloride in slit pores, we compared the ...
2006-05-18
International Nuclear Information System (INIS)
Ab initio total energy calculations within the framework of density functional theory have been performed for water molecule adsorption on the (0001) surface of double hexagonal packed americium using a full-potential all-electron linearized augmented plane wave plus local orbitals method (FP-L/APW+lo). Subsequent partial dissociation (OH+H) and complete dissociation (H+O+H) of the water molecule have been examined. The completely dissociated H+O+H configuration exhibit the strongest binding with the surface (3.35 eV), followed by partially dissociated species OH+H (2.23 eV), with all molecular H_2O configurations showing weak physisorption (0.366 eV). For molecular adsorptions, the flat lying orientation of the water molecule if found to be more favorable for majority of the cases. In the case of partial dissociation (OH+H), the vertical orientation of OH molecule with O facing the surface adsorbed at a h3 adsorption site and the H atom adsorbed at another ...
2009-06-01
International Nuclear Information System (INIS)
Ab initio total energy calculations within the framework of density functional theory have been performed for atomic hydrogen and oxygen chemisorption on the (0001) surface of double hexagonal packed (dhcp) americium using a full-potential all-electron linearized augmented plane wave plus local orbitals method. Chemisorption energies were optimized with respect to the distance of the adatom from the relaxed surface for three adsorption sites, namely top, bridge, and hollow hcp sites, the ad-layer structure corresponding to the coverage of a 0.25 monolayer in all cases. Chemisorption energies were computed at the scalar-relativistic level (no spin-orbit coupling NSOC) and at the fully relativistic level (with spin-orbit coupling SOC). The two-fold bridge adsorption site was found to be the most stable site for O at both the NSOC and SOC theoretical levels with chemisorption energies of 8.204 eV and 8.368 eV respectively, while the three-fold hollow hcp adsorption ...
2008-02-01
International Nuclear Information System (INIS)
Carbon stable isotope trichloroethylene ("1"3C TCE) was used to investigate the formation of chloromethane (CM) during the electrolytic dechlorination of trichloroethylene (TCE) at a granular-graphite packed cathode. A method was developed to use a conventional GC/MS to analyze and quantify regular and "1"3C TCE and their dechlorination products. The concentration of a "1"3C compound can be calculated, based on the concentration of its regular counterpart, from the response ratio of two fragments of different mass per charge values from the compounds in a sample and two characteristic MS spectrum ratios: one is the response ratio of the two fragments of the regular compound, and the other is the response ratio of the corresponding fragments of the regular and "1"3C compounds at the same concentrations. The method was used to analyze the regular and "1"3C compounds observed in an experiment of dechlorination in an ammonium acetate solution that contained both ...
2007-03-22
Tribological coatings for liquid metal and irradiation environments
International Nuclear Information System (INIS)
Several metallurgical coatings have been developed that provide good tribological performances in high-temperature liquid sodium and that are relatively unaffected by neutron fluences to 6 X 10/sup 22/ n/cm/sup 2/ (E > 0.1 MeV). The coatings that have consistently provided the best tribological performance have been the nickel aluminide diffusion coatings created by the pack cementation process, chromium carbide or Tribaloy 700 trade mark (a nickel-base hardfacing alloy) applied by the detonation-gun process, and chromium carbide and other hardfacing alloy) applied by the detonation-gun process, and chromium carbide and other hardfacing materials applied by the electro-spark deposition process. The latter process is a relatively recent development for nuclear applications and is expected to find wide usage. Other coating processes, such as plasma-spray coating, sputtering, and chemical vapor deposition, were candidates for use on various components, but the ...
Transportation container for Li/SO/sub 2/ batteries on passenger aircraft
Energy Technology Data Exchange (ETDEWEB)
A surplus USN 40 mm ammunition can was subjected to a variety of tests. Pressure tests were carried out with nitrogen gas, followed by the venting of actual Li/SO/sub 2/ cells and batteries inside the can. A fire test was also conducted on a can packed with 10 each 10-cell batteries surrounded by vermiculite. Test results indicate the US Navy (USN) 40-mm ammunition can is suitable as a shipping container for Li/SO/sub 2/ batteries on passenger aircraft. To provide a further measure of safety, a sulfur dioxide getter was incorporated into the can. Studies indicated a commercial material, ASC carbon, is suitable for this purpose. The granular material was packaged in porous paper desiccant bags and placed in the can with the batteries and vermiculite. The batteries were vented inside the sealed can and the internal pressure monitored. Pressure returned to normal within several minutes, indicating that this arrangement should prevent sulfur dioxide (SO/sub 2/) gas ...
1987-01-01
International Nuclear Information System (INIS)
The rates of spontaneous interbilayer and transbilayer exchange of ["3H]dimyristoylphosphatidylcholine (["3H]DMPC) were examined in the DMPC and DMPC/dimyristoylphosphatidylethanolamine (DMPE) large unilamellar vesicles in the liquid-crystalline-, gel-, and mixed-phase states. DMPC desorption rates from either gel or liquid-crystalline phases containing DMPE are very similar to the corresponding rates from pure DMPC gel or liquid-crystalline phases. The authors proposed that the DMPC/DSPC behavior results from packing defects in gel phases composed of both DMPC and DSPC molecules because of the four-carbon difference in the acyl chain lengths of the two species. The present results strongly support this hypothesis because no such anomalous behavior is observed in DMPC/DMPE, which is similar to DMPC/DSPC in phase behavior but does not have the chain length difference. These results are not consistent with lipid headgroup dehydration as the major energetic barrier to ...
The study of anemia in fowl spirochetosis using radioactive iron
International Nuclear Information System (INIS)
Radioactive iron is used to follow up some haematologic indices in birds infected with irradiated spirochetes of the Borrelia anderina species. Use is made of a total of 90 cockerels, aged two months, divided into three groups: 1st group - cockerels inoculated with spirochetes that had been gamma-irradiated at the rate of 40000 R; 2nd group - cockerels inoculated with untreated spirochetes; and 3rd group - normal cockerels. The infective material consisted of strain Rouen spirochetes of the Pamoukchii serotype. Radiometric studies were also carried out for establishing to what extent radioactive iron is incorporated in the erythrocytes and is deposited in the liver, spleen, and marrow of the investigated birds. Classical methods of investigation were employed to determine the erythrocyte, leukocyte, and thrombocyte counts, the haemoglobin content (after Sahli) as well as the erythrocyte pack after the method of Todorov. It is found that the inoculation of ...
The effect of irradiation on packaging materials
International Nuclear Information System (INIS)
Ionizing radiation, mainly in the form of #gamma#-rays from the radioisotope cobalt 60, is being used increasingly for the inactivation of contaminants in cosmetic and toiletry preparations. The treatment is applied to the product in its final pack, and therefore, it is important to recognize that the properties of the packaging materials could be affected, particularly if high radiation doses are used. The stability of a wide range of materials is discussed. The nature and extent of chemical and physical changes in plastics very much depends on the presence of antioxidants and other additives, and on the environmental conditions during irradiation. Some useful information is available from research into the use of radiation for the preservation of food - many films and laminates have been cleared for use in the United States. The low radiation doses used for the control of contaminants in cosmetic products are quite unlikely to cause changes in packaging materials ...
International Nuclear Information System (INIS)
The detailed electronic energy band structure of hexagonal close-packed #alpha#-zirconium, corresponding to the atomic configuration of 4d"25s"2 of its four outermost valence electrons, has been computed by the composite-wave variational version of the augmented-plane-wave(APW) method in conjunction with the X#alpha#(#alpha# = 0.70424) exchange approximation for obtaining the potentials. From these data the electronic density of states and its angular-momentum-decomposed components have been obtained by the Raubenheimer-Gilat method. These quantities are required in order to calculate the electron-phonon interaction parameter (lambda) and the superconducting transition temperature (Tsub(c)) within the framework of the theories of Gaspari and Gyorffy and McMillan. A study of the variation of Tsub(c) with the Coulomb pseudopotential (#mu#*) revealed that #mu#* = 0.1 yields the best agreement between theory and experiment for #alpha#-Zr. Also studied from the energy ...
Study on the use of coal ash reclaimed land as upland-fields (Part 2)
Energy Technology Data Exchange (ETDEWEB)
Soil dressing on coal ash reclaimed land is a covering to use the land for agriculture. This study was carried out to find out the necessary depth of soil covering the ash layer in order to have normal crop growth. Two kinds of crops, Japanese radish, and rakkyo were planted in cover soil on the fly ash packed in wooden boxe (90 cm x 90 cm x 90 cm). Depths of cover soil were 20 cm, 30 cm, 40 cm and 50 cm. The results were summarized as follows: growth and yield of Japanese radish and rakkyo were increased with increasing depth of cover soil; root development of Japanese radish was inhibited at the lower coal ash layer. Main root length and edible root length of Japanese radish were decreased with decreasing depth of cover soil; boron and molybdenum contents in the plants remarkably increased with decreasing depth of cover soil. This may be due to the absorption of these elements from fly ash layer; it is concluded that optimum depth of cover soil should be more ...
1987-01-01
Study of the Photon Strength Functions for Gadolinium Isotopes with the DANCE Array
The gadolinium isotopes are interesting for reactor applications as well as for medicine and astrophysics. The gadolinium isotopes have some of the largest neutron capture cross sections. As a consequence they are used in the control rod in reactor fuel assembly. From the basic science point of view, there are seven stable isotopes of gadolinium with varying degrees of deformation. Therefore they provide a good testing ground for the study of deformation dependent structure such as the scissors mode. Decay gamma rays following neutron capture on Gd isotopes are detected by the DANCE array, which is located at flight path 14 at the Lujan Neutron Scattering Center at Los Alamos National Laboratory. The high segmentation and close packing of the detector array enable gamma-ray multiplicity measurements. The calorimetric properties of the DANCE array coupled with the neutron time-of-flight technique enables one to gate on a specific resonance of a specific isotope in ...
2009-03-10
Energy Technology Data Exchange (ETDEWEB)
The retention indices of cycloalkenes and cycloalkadienes with C/sub 6/-C/sub 13/ rings are determined by gas-liquid chromatography (GLC) on glass capillary columns coated with OV-1 and Ucon LB 550X and by gas-solid chromatrography (GSC) on a microcolumn packed with uncoated graphitized thermal carbon black (GTCB). Structure-retention correlations are derived on using index differences such as H/sup OV/, H/sup GTCB/ and ..delta..I values, considering the differences in the stereochemistry of these compounds. It is shown that the combined application of index increments obtained in GLC and GSC provides more detaled structure informations. The value of the retention index units agree with the most stable conformations of the alicyclic compounds. The high value for the energy equivalent to an index unit (..delta..G/sub I.U./ = 4.18 kJ/mol) confirms that graphitized thermal carbon black causes much stronger dispersive interactions than any nonpolar liquid phase.
1987-08-01
Stabilization and limit theorems for geometric functionals of Gibbs point processes
Given a Gibbs point process $\\P^{\\Psi}$ on $\\R^d$ having a weak enough potential $\\Psi$, we consider the random measures $\\mu_\\la := \\sum_{x \\in \\P^{\\Psi} \\cap Q_\\la} \\xi(x, \\P^{\\Psi} \\cap Q_\\la) \\delta_{x/\\la^{1/d}}$, where $Q_{\\la} := [-\\la^{1/d}/2,\\la^{1/d}/2]^d$ is the volume $\\la$ cube and where $\\xi(\\cdot,\\cdot)$ is a translation invariant stabilizing functional. Subject to $\\Psi$ satisfying a localization property and translation invariance, we establish weak laws of large numbers for $\\la^{-1} \\mu_\\la(f)$, $f$ a bounded test function on $\\R^d$, and weak convergence of $\\la^{-1/2} \\mu_\\la(f),$ suitably centered, to a Gaussian field acting on bounded test functions. The result yields limit laws for geometric functionals on Gibbs point processes including the Strauss and area interaction point processes as well as more general point processes defined by the Widom-Rowlinson and hard-core model. We provide applications to random sequential ...
2008-01-01
British Library Electronic Table of Contents (United Kingdom)
A series of NHC silver(I), mercury(II) and palladium(II) complexes, [(1,3-diethylbimy)6Ag4I3]I (2), [(1-benzyl-3-picolylbimy)Ag2Br2]n (3), [(1-benzyl-3-picolylbimy)HgI(CH2CN)]2 (4), {[(1-picolyl-3-npropylbimy)2Hg][Hg2I6]}n (5) and [(1,3-dipicolylbimy)PdCl]Cl (6), as well as one anionic complex [1,3-diethylbimidazolium]2[HgI4] (1) (bimy=benzimidazol-2-ylidene), have been prepared and characterized. Interestingly, a wind wheel-like Ag4I3 arrangement in 2 is formed, 1D polymeric chain containing 12-membered macrometallocycles and quadrangle Ag2Br2 units in 3 is generated, and the a-carbon atom of deprotonated acetonitrile ([CH2CN]-) in 4 participates in coordination with mercury(II) atom. In the crystal packings of complexes 1-6, 2D supramolecular layers or 3D supramolecular architectures are...
2011-01-01
Rheology of zirconia suspensions in a nonpolar organic medium
Energy Technology Data Exchange (ETDEWEB)
Three dispersants (stearic acid, oleic acid, and poly-(12-hydroxystearic acid)) are compared for their ability to produce low-viscosity suspensions of zirconia in kerosene. Rheological measurements and sediment packing density measurements show that poly(12-hydroxystearic acid) is a better dispersant than stearic acid or oleic acid; this is explained in terms of the longer tail of the poly-(12-hydroxystearic acid) surfactant molecule. The amount of dispersant can be optimized to reduce viscosity and yield point of the suspension, and to eliminate thixotropic hysteresis. The use of a dispersion medium of lower viscosity than the dispersant makes it easy to detect when complete monolayer coverage has been achieved. The loss of pseudoplasticity, brought about by a higher degree of deflocculation, can be recovered by increasing the volume fraction of solids of a suspension and this is beneficial in the plastic forming of ceramics. Rheological measurements showed that ...
1995-12-01
Removal of iodine species by concentrated nitric acid, (2)
International Nuclear Information System (INIS)
One of the most effective removing processes of iodine species is what is called ''Iodox Process'', which contains oxidation and absorption of iodine species by highly concentrated nitric acid. The result of fundamental test with bubble column in this process had been reported. Present paper describes the fundamental experiment by the use of packed column. This experiment has been carried out to clear the effect of feed gas flow rate, nitric acid flow rate, nitric acid concentration, and methyl iodide concentration on removal efficiency of methyl iodide. The following results were obtained. The decontamination factor of methyl iodide (DF) increases exponentially with nitric acid concentration, which agrees with the result obtained by using the bubble column. The factor is in inverse proportion to feed gas flow rate, and is also almost independent of nitric acid flow rate and methyl iodide concentration. The relation between the decontamination factor and the ...
1978-07-01
Reduction of CO{sub 2} concentration in a zinc/air battery by absorption in a rotating packed bed
Energy Technology Data Exchange (ETDEWEB)
The reduction of CO{sub 2} concentration in a gas stream containing 500ppm of CO{sub 2} by a technique combining chemical absorption with Higee (high gravity) was investigated in this study. Using a 2.0L aqueous amine-based solution to treat the feed gas with a flow rate which varied from 12.9 to 20.6Lmin{sup -1}, piperazine (PZ) was found to be more effective than 2-(2-aminoethylamino) ethanol (AEEA) and monoethanolamine (MEA) for reducing the CO{sub 2} concentration to a level below 20ppm. The effects of temperature, rotating speed, amine solution flow rate, and gas flow rate on the removal efficiency of CO{sub 2} were systematically examined. The results indicated that the proposed compact device could effectively reduce CO{sub 2} to a level below 20ppm, as required by a zinc/air battery, for a long period of time using PZ and its mixture with AEEA and MEA as the absorbents. (author)
2006-11-22
Energy Technology Data Exchange (ETDEWEB)
GSTD1 is one of several insect glutathione S-transferases capable of metabolizing the insecticide DDT. Here we use crystallography and NMR to elucidate the binding of DDT and glutathione to GSTD1. The crystal structure of Drosophila melanogaster GSTD1 has been determined to 1.1 {angstrom} resolution, which reveals that the enzyme adopts the canonical GST fold but with a partially occluded active site caused by the packing of a C-terminal helix against one wall of the binding site for substrates. This helix would need to unwind or be displaced to enable catalysis. When the C-terminal helix is removed from the model of the crystal structure, DDT can be computationally docked into the active site in an orientation favoring catalysis. Two-dimensional {sup 1}H,{sup 15}N heteronuclear single-quantum coherence NMR experiments of GSTD1 indicate that conformational changes occur upon glutathione and DDT binding and the residues that broaden upon DDT binding support the ...
2010-06-14
Radiation processing as a post-harvest quarantine control for raisins, dried figs and dried apricots
International Nuclear Information System (INIS)
The commercially packed samples of raisins, dried figs and dried apricots were irradiated using doses in the range of 0.5-1.0 kGy for disinfestation and 0.5-5.0 kGy for sensory analysis with the dose rate ranging from 1.44 to 1.92 kGy/h. Pests on dried fruits were evaluated after 0, 1, 2 and 3 months of storage for irradiated dried figs and 1, 3, 6 and 12 months of storage for raisins and dried apricots. Sensory analysis of dried figs, dried apricots and raisins were carried out after 0, 1, 3, 6 and 12 months of storage. The results indicated that radiation processing at low doses (#approx#1.0 kGy) is an effective post-harvest treatment and quarantine control for these products with no adverse effects on sensory (marketing) attributes.
2006-03-01
DEFF Research Database (Denmark)
Various MLM-type (M, medium-chain fatty acids; L, long-chain fatty acids) structured triacylglycerols were produced in pilot- or small-scale packed-bed reactors by lipase-catalyzed acidolysis. The incorporation and acyl migration of octanoic acid were measured by gas chromatography and Grignard degradation, and ranged from 39.0 to 48.7% and 0.6 to 9.3%, respectively. Quantitation of triacylglycerol molecular species was performed by ammonia negative ion chemical ionization (NICI) mass spectrometry (MS). The proportion of ACN (acyl carbon number) 34 species that contained one C-18 fatty acid and two C-8:0, in samples analyzed, varied from 12.5 to 23.2%. The selected regioisomers MLM and MML within the ACN 34 species group were quantified by NICI tandem MS (MS/MS) and were in the range of 97.1 to 98.4% and 1.6 to 2.9%, respectively. There was no correlation between the level of acyl migration during lipase-catalyzed esterification and the level of regioisomers of the ...
2001-01-01
Pilot-scale testing of pyrolysis for the volume reduction of organic waste
Energy Technology Data Exchange (ETDEWEB)
Pilot-scale pyrolysis units have been in operation since 1980 to test the efficiency of thermal treatment of transuranic (TRU) solid waste to retrieve the TRUs and to reduce the volume of wastes such as spent solvent, spent resin, and others. These wastes are generated by reprocessing, fuel production, and utilities. NUKEM has developed a criticality-safe, ring-slab reactor to decompose solid TRU waste. The plant processes 25 kg/h with a polyvinyl chloride content up to 70%. The overall throughput (inactive) up to the spring of 1982 was 2000 kg. The decontamination factor for the reactor itself is 1000. The liquid wastes, mainly spent solvent, are cracked under nitrogen at 400 to 700/sup 0/C in a reactor that is filled by a packed bed kept in motion by a specially designed agitator. This unit was built for 15 kg/h water equivalent evaporation. Up to 1982 the unit processed 2000 kg of spent solvent (simulated) overall. The decontamination factor is similar to the ...
1982-11-01
Pilot-scale testing of pyrolysis for the volume reduction of organic waste
International Nuclear Information System (INIS)
Pilot-scale pyrolysis units have been in operation since 1980 to test the efficiency of thermal treatment of transuranic (TRU) solid waste to retrieve the TRUs and to reduce the volume of wastes such as spent solvent, spent resin, and others. These wastes are generated by reprocessing, fuel production, and utilities. NUKEM has developed a criticality-safe, ring-slab reactor to decompose solid TRU waste. The plant processes 25 kg/h with a polyvinyl chloride content up to 70%. The overall throughput (inactive) up to the spring of 1982 was 2000 kg. The decontamination factor for the reactor itself is 1000. The liquid wastes, mainly spent solvent, are cracked under nitrogen at 400 to 700"0C in a reactor that is filled by a packed bed kept in motion by a specially designed agitator. This unit was built for 15 kg/h water equivalent evaporation. Up to 1982 the unit processed 2000 kg of spent solvent (simulated) overall. The decontamination factor is similar to the figures ...
Energy Technology Data Exchange (ETDEWEB)
The selective catalytic reduction of nitric oxide by methane over copper ion-exchanged natural zeolites was investigated in a packed-bed tubular reactor. The catalytic activity of Cu-N and Cu-H-N catalysts was confirmed as NO, CH{sub 4}, and O{sub 2} displayed very little reaction in the absence of any catalyst and zeolite without ion exchange was totally inactive. A maximum NO conversion of 33% at 650 C for Cu-N-66 was achieved with 2% NO and 1% CH{sub 4} and a contact time of 0.9 g s/cm{sup 3}, but the introduction of 2% O{sub 2} reduced the NO conversion to only 12%. Ion exchange for the H-form prior to copper ion exchange was essential for oxygen to promote catalytic activity over the temperature range 250--650 C, with a maximum conversion of 30% at 450 C with O{sub 2} present. The direct reduction of NO by methane was ruled out as a possible reaction pathway.
1997-11-01
Natural convection cooling of a close-packed array of AGR fuel pins surrounded by graphite debris
International Nuclear Information System (INIS)
Certain postulated faults during refuelling of AGRs may give rise to compacted fuel and graphite sleeve debris. This debris must be maintained below some safe limiting temperature. As part of a programme to assess the benefits of natural convection in cooling such debris in a region experiencing no forced cooling, a simple geometry incorporating typical debris has been studied both experimentally and by prediction. The experiment comprised an array of electrically heated fuel rods mounted co-axially in a closed cylindrical vessel and surrounded by fragments of graphite. The vessel was cooled on its cylindrical surface, the ends being insulated. Rods and vessel wall were thermocoupled. Tests covered a range of temperature and pressures in both CO_2 and N_2. Significant natural convection heat removal was demonstrated, particularly at high pressure. Predictions utilising the PHOENICS code agreed well with measured temperatures over a wide range of test conditions. (orig.).
Metal Coupled Folding of Cys2His2 Zinc-Finger
Zinc-fingers, which widely exist in eukaryotic cell and play crucial roles in life processes, depend on the binding of zinc ion for their proper folding. To computationally study the zinc coupled folding of the zinc-fingers, charge transfer and metal induced protonation/deprotonation effects have to be considered. Here, by attempting to implicitly account for such effects in classical molecular dynamics and performing intensive simulations with explicit solvent for the peptides with and without zinc binding, we investigate the folding of the Cys2His2 type zinc-finger motif and the coupling between the peptide folding and zinc binding. We find that zinc ion not only stabilizes the native structure, but also participates in the whole folding process. It binds to the peptide at early stage of folding, and directs or modulates the folding and stabilizations of the component beta-hairpin and alpha-helix. Such a crucial role of zinc binding is mediated by the packing of ...
2008-01-01
Energy Technology Data Exchange (ETDEWEB)
A three-dimensional mathematical model has been developed as a tool for furnace structure design and operation conditions optimization when the straw combustion is in oxygen-enriched or conventional air atmospheres. Mathematical methods have been used based on a combination of FLIC (A fluid Dynamic Incinerator Code) code for the in-bed incineration and commercial software FLUENT for the over-bed combustion. Oxygen-enriched atmospheres promote the destruction of most pollutants due to the high oxygen partial pressures and temperatures, which is reflected by very low residual amounts of organic combustion by-products in the bottom ash and flue gas of the straw-fired boiler unit. The predictions indicated that the maximum combustion temperature is around 1500 K, CO emission is 201 vppm and O{sub 2} concentration is about 6.9 vol% at furnace exit, and it is shown that mathematical models can serve as a reliable tool for detailed analysis of straw combustion processes in the ...
2010-05-15
Ludwig's Applied Process Design for Chemical and Petrochemical Plants, 4th Edition - EA BOOKS
...Ludwig's Applied Process Design for Chemical and Petrochemical Plants, 4th Edition - EA BOOKS nomographs, data charts and heuristics. About us | My EA Books | Contact us | Authors Home page Feature Books Books DVDs eBooks EA Books Publications Merchandise eJournals Terms and Conditions Subjects Chemical & Process Civil Computers Electrical & Electronics Environmental Management Mechanical Multi-disciplinary Quality Railways Structural Water Australian Authors Australian Rainfall ... Volume Two focuses on distillation and packed towers, and presents the methods and fundamentals of plant design along with supplemental mechanical and related data, nomographs, data charts and heuristics. The Fourth Edition is significantly expanded and updated, with new topics that ensure readers can analyze problems and find practical design methods and solutions to accomplish their process design objectives. It is a true application-driven book, providing ...
Low-cost FPSO for service in the Zaafarana oil field
Energy Technology Data Exchange (ETDEWEB)
The Zaafarana oilfield development, operated by Zaafarana Oil Co. (Zafco) presented a series of unique challenges, including redeployment of an internal-turret mooring system, use of a turret-based electrical-cable jumper system, and permanent use of cable-deployed electric submersible pumps in the gravel-pack well completions. Following a detailed three-dimensional (3D) seismic program, the field was discovered by the first well in December 1990. Four subsequent appraisal wells were drilled. The discovery well and two of the appraisal wells tested oil at rates ranging from 2,000 to 10,100 B/D. Initial development plans called for the use of two conventional platforms with a pipeline to a shore-based treatment and storage terminal. Data acquired from subsequent wells were incorporated into the mapping and reserve estimates resulting in a sharp downgrade of the estimated recoverable reserves. The reduced estimate, combined with a revised pricing scenario, ...
1997-04-01
Low temperature humidification dehumidification desalination process
Energy Technology Data Exchange (ETDEWEB)
The humidification dehumidification desalination process is viewed as a promising technique for small capacity production plants. The process has several attractive features, which include operation at low temperature, ability to utilize sustainable energy sources, i.e. solar and geothermal, and requirements of low technology level. This paper evaluates the characteristics of the humidification dehumidification desalination process as a function of operating conditions. A small capacity experimental system is used to evaluate the process characteristics as a function of the flow rate of the water and air streams, the temperature of the water stream and the temperature of the cooling water stream. The experimental system includes a packed humidification column, a double pipe glass condenser, a constant temperature water circulation tank and a chiller for cooling water. The water production is found to depend strongly on the hot water temperature. Also, the water ...
2006-03-01
Low temperature humidification dehumidification desalination process
International Nuclear Information System (INIS)
The humidification dehumidification desalination process is viewed as a promising technique for small capacity production plants. The process has several attractive features, which include operation at low temperature, ability to utilize sustainable energy sources, i.e. solar and geothermal, and requirements of low technology level. This paper evaluates the characteristics of the humidification dehumidification desalination process as a function of operating conditions. A small capacity experimental system is used to evaluate the process characteristics as a function of the flow rate of the water and air streams, the temperature of the water stream and the temperature of the cooling water stream. The experimental system includes a packed humidification column, a double pipe glass condenser, a constant temperature water circulation tank and a chiller for cooling water. The water production is found to depend strongly on the hot water temperature. Also, the water ...
2006-03-01
Lipid domain formation modulates activities of snake venom phospholipase A(2) enzymes.
The goal of the present study is to elucidate the effect of lipid domain formation on activities of Naja naja atra and Bungarus multicinctus phospholipase A(2) (PLA(2)) enzymes. Sphingomyelin inhibited enzymatic activity and membrane-damaging activity of PLA(2) against egg yolk phosphatidylcholine (EYPC), while cholesterol and cholesterol sulfate abrogated the inhibitory effect of sphingomyelin. The ability of cholesterol and cholesterol sulfate to abolish the inhibitory effect of sphingomyelin was closely related to their capacity to induce domain formation in EYPC/sphingomyelin vesicles. Laurdan fluorescence measurement revealed that membrane packing of EYPC/sphingomyelin vesicles was differently affected by cholesterol and cholesterol sulfate. Unlike cholesterol, cholesterol sulfate was unable to promote domain formation in dipalmitoylphosphatidylcholine (DPPC) vesicles. Cholesterol increased but cholesterol sulfate reduced PLA(2) activity against DPPC. ...
2010-08-10
Energy Technology Data Exchange (ETDEWEB)
A laboratory differential simulation method is used for the design of carbonization columns at coal-tar processing in which phenols are regenerated from phenolate solution by carbon dioxide absorption. The design method is based on integration of local absorption rates of carbon dioxide along the column. The local absorption rates into industrial phenolate mixture are measured in a laboratory model contactor for various compositions of the gas and liquid phases under the conditions that ensure the absorption rates in the laboratory absorber simulate the local rates in the industrial column. On the bases of the calculations, two-step carbonization columns were designed for 30000 t/year of the phenolate solution treatment by carbon dioxide. The absorption proceeds at higher pressure of 500 kPa and temperatures from 50 to 65 C, pure carbon dioxide is used and toluene is added. These conditions have the following favourable effects: (I) significant size reduction of the columns, (ii) it is ...
2009-01-15
International Nuclear Information System (INIS)
Spices and packaging materials were exposed to gamma irradiation at a dose of 10 KGy. Luncheon was prepared with irradiated or non-irradiated spices. Prepared luncheon was packaged in irradiated or non-irradiated packaging materials. Packaged luncheon was treated with 2 KGy. Treated and untreated packaged luncheon were kept in a refrigerator (1-4 Centigrade) for 12 months. Microbiological, nutritive and chemical characteristics of luncheon were evaluated after processing and during storage; whereas, sensory quality was evaluated only after irradiation. Gamma irradiation decreased the microorganisms counts of spices, packaging materials and packed luncheon and increased the shelf-life of packaged luncheon products. No major differences in moisture, protein, fat, ph value, total acidity, lipid peroxide and volatile basic nitrogen were observed due to irradiation. Sensory evaluation showed that all the combination treated luncheon were acceptable regarding sensory ...
International Nuclear Information System (INIS)
The phase transition behaviour of polyethylene-b-poly(ethylene oxide) (PE-b-PEO) diblock copolymer with relatively short chain lengths has been studied on the basis of temperature dependent infrared and Raman spectral measurements and synchrotron WAXD/SAXS simultaneous measurements, from which the concrete structural changes were deduced successfully from the various levels of molecular chain conformation, chain packing mode and higher-order structure. The higher-order structure has been found to transform between lamella, perforated lamella, gyroid, cylinder and sphere structures. The inner structural changes occurring in the polyethylene and poly(ethylene oxide) parts have been related with these morphological changes. The morphological transition from lamella to gyroid occurs with keeping the crystalline state of polyethylene parts. This apparently curious transition can be interpreted reasonably by assuming the thermally-activated chain motion in the crystal ...
2009-08-01
Experimental Evaluation of Tude Support Plate Crevice Chemistry
Energy Technology Data Exchange (ETDEWEB)
A test methodology for measuring temperature, impedance, pH, and electrochemical potential distributions within a sludge-packed tube support plate crevice in a laboratory test is described. The method successfully showed that there were large concentration gradients between the tube and tube support plate sides of the crevice. The testing also showed that strong bases concentrated more effectively than strong acids, and that the crevice pH, when exposed to seawater-based solutions, increased with increasing superheat and decreasing bulk concentration. The large variations in the crevice chemistry observed under heat transfer were eliminated upon shutdown. These new test data suggest that it might be beneficial to evaluate the variation in the extent of stress corrosion cracking with tube support plate elevation found in some steam generators in light of local chemistry changes, as well as the variation in tubing temperature. Because of the large crevice chemistry ...
2001-05-08
Energy Technology Data Exchange (ETDEWEB)
The objective of this Energy Engineering Analysis (EEA) for LSAAP is threefold: Develop a systematic plan of projects which will result in reducing energy consumption. Consider renewable energy sources with the objective of establishing an orderly procedure for reducing use of non-renewable energy sources. Determine the feasibility of Total Energy (TE), Selective Energy (SE), and Central Heating Plant (CHP) concepts using alternative fuels. In essence, an assessment of the entire energy picture at LSAAP was undertaken. This report is a summary of that effort. LSAAP was originally built during 1941 and 1942 as a shell loading plant for the Army. After World War II, the facility was deactivated until 1951 when it was reactivated as a Government Owned, Contractor Operated (GOCO) facility. Day and Zimmerman was selected as the operator in 1951 and has been the operating contractor ever since. Located just west of Texarkana, Texas, LSAAP encompasses an area of approximately 15,546 acres. ...
1981-12-31
International Nuclear Information System (INIS)
The detailed energy-band structure of hexagonal-close-packed technetium, corresponding to the atomic configuration 4d"55s"2 of its seven outermost valence electrons, has been obtained throughout the Brillouin zone using the composite-wave variational version of the augmented-plane-wave (APW) method in conjunction with the X#alpha# (#alpha# = 0.702 99) exchange approximation for obtaining the potentials. From the band-structure data the electronic density of states (DOS) and the angular-momentum--decomposed DOS were calculated by the accurate Gilat-Raubenheimer method. These quantities were used to calculate the electron-phonon coupling constant and the transition temperature (T/sub c/) using the theories of Gaspari and Gyorffy and of McMillan. Also studied were the Fermi surface and the optical properties of Tc via the imaginary part of the interband dielectric constant for bound electrons, the latter being the first of such a study on Tc to date. The ...
Energy Technology Data Exchange (ETDEWEB)
Two major modes of CO adsorption on SiO{sub 2}-supported Pd reflect different extents of back-donation, which is, at least in part, controlled by the local electron density at the adsorption site. The fraction of CO in the bridging mode (B) increases and that of the linear mode (L) decreases, with increasing size of the Pd particles, indicating high electron density at Pd atoms in terraces of close-packed crystal faces, in agreement with Smoluchowski's classical model. For samples reduced at 300{degree}C our data points and those of other authors are located on a common curve of B/L vs metal dispersion. Extensive reduction at 600{degree}C results in significantly lower B/L values, attributed to the incipient formation of a palladium silicide. Oxidation followed by reduction at 300{degree}C destroys the silicide, and the B/L value returns to the original curve.
1989-06-15
Two major modes of CO adsorption on SiO{sub 2}-supported Pd reflect different extents of back-donation, which is, at least in part, controlled by the local electron density at the adsorption site. The fraction of CO in the bridging mode (B) increases and that of the linear mode (L) decreases, with increasing size of the Pd particles, indicating high electron density at Pd atoms in terraces of close-packed crystal faces, in agreement with Smoluchowski's classical model. For samples reduced at 300{degree}C our data points and those of other authors are located on a common curve of B/L vs metal dispersion. Extensive reduction at 600{degree}C results in significantly lower B/L values, attributed to the incipient formation of a palladium silicide. Oxidation followed by reduction at 300{degree}C destroys the silicide, and the B/L value returns to the original curve.
1989-06-15
Effects of oxygen, copper and acid chlorides on denting corrosion
Energy Technology Data Exchange (ETDEWEB)
The effect of dissolved oxygen and copper on denting corrosion at 280/sup 0/C in solutions of NaCl at pH 9 with ammonia was investigated using a packed tube/support plate crevice in a laboratory simulation. The onset of corrosion was detected with a hydrogen analyzer sensitive to 0.2 ppB. In the absence of copper, rapidly rising hydrogen concentrations were detected only when the product of the chloride and oxygen concentrations were detected only when the product of the chloride and oxygen concentrations in the boiler-water exceeded 25 (ppM)/sup 2/, but at these high concentrations, unheated low-carbon steel surfaces in the system were as sensitive to corrosion as the heated crevice. When copper metal was present in the feed system, corrosion of the heated crevice occurred in the absence of oxygen, provided the copper had previously been exposed to dissolved oxygen. Dosing hydrazine into the feedwater eventually suppressed the ability of copper to initiate ...
1986-07-01
Energy Technology Data Exchange (ETDEWEB)
Effects of gamma irradiation on essential oils of five medicinal plants i.e. dried seeds of piper cubeba(cubeb), piper nigrum(black pepper), piper retrofractum, amomum cardamomum(cardamom) and myristica fragrans(mace), packed in low density polyethylene bag of 0.13 mm thickness have been investigated. After being irradiated at doses of 5 and 10 kGy, a part of the samples was analysed, and the rest were stored for six months at temperature of 30 +- 2 degC, and humidity ranging from 70 to 95%. The essential oil characteristics of control, irradiated and six month stored samples were analysed using infrared and ultraviolet spectrophotometers, HPLC, GLC and refractometer. Other parameters observed were moisture content and essential oil content of the samples. Results showed that irradiation up to a dose of 10 kGy do not give any significant effect on these parameters. Significant changes were only found in the essential oil content of piper cubeba, caused by storage ...
1983-12-01
Distribution of activation energies for impurity hopping in amorphous metals
Energy Technology Data Exchange (ETDEWEB)
The distribution of activation energies ..delta.. for classical over-the-barrier hopping is computed for a model amorphous metal. The spread in ..delta.. is determined by the variation in equilibrium-site and saddle-point sizes for the assumed model of dense random packing (DRP) of soft spheres. The size distribution is related to the radial distribution function in a manner which reproduces recent numerical results for the interstitials in DRP models. Size (distance) variation in general is related to energy variation by the form of the potential energy V(r). We show, however, that the distribution of equilibrium-site energies can be related directly to the impurity-induced lattice expansion and bulk modulus without detailed knowledge of V(r). The form of V(r) is necessary for the saddle-point distribution, and we estimate this using simple analytic expressions which fit the observed lattice expansion and impurity (hydrogen) vibrational frequency. The effects of a ...
1983-02-15
Development of a high performance air heater through use of an evacuated tube cover design
Development of a high performance air heater through use of an evacuated tube cover design is described. The cover design utilizes evacuated fluorescent light tubes laid parallel in a close packed array to form an inner transparent glazing over a conventional metal absorber plate with flow behind the plate. A tempered flat glass plate was used as an outer glazing. Both clear and infrared reflective (IR) tubes were investigated. Solar transmittance tests indicate that the clear tube array has a higher transmittance than two flat sheets of low-iron glass. The IR coating produced substantial transmittance loss. Thermal conductance tests indicate that the tubes behave similar to two flat glass sheets with a vacuum in between. The IR reflective coating was only marginally effective at reducing heat conductance. Final prototype designs are presented along with collector performance estimates.
1980-01-01
Crud removal performance with ion exchange resins in BWR plants
Energy Technology Data Exchange (ETDEWEB)
It is needless to say that one of the most important roles of the condensate demineralizer in Japanese boiling water reactors (BWR) is to eliminate such impurities during accidental occurrence of sea water leakage from condensate cooling system. Ion exchange resins packed in condensate demineralizer have also been expected to decrease crud, or corrosion products (CP) in condensate water in order to finally reduce activated corrosion products (ACP) in the reactor coolant loop. It is perceived that crud removal ability of a condensate demineralizer has been improved year by year. And we call this phenomenon as `Aging Effect`. Typical property changes of aged cation exchange resin consisted of an increase of water retention capacity and a change of surface texture. Based on these findings, we formulated a new concept and developed new gel type ion exchange resins for the better crud removal. The results from column tests using actual condensate water for approximately ...
1996-01-01
Approximate analysis of non-uniform gas flow through layered burdens
Energy Technology Data Exchange (ETDEWEB)
An approximate analyzing model was developed to predict the azimuth of zigzag streamline, the distribution ratio between two neighboring layers and the radial distribution among the layers of the gas passing through the shaft of blast furnace loaded in layers. The theoretical basis of the approximate analysis is composed of the material balance derived from the assumption that any stream line surrounded with two streamlines is isolated and no material transfer occurs through the tube wall, and of the energy theory that the stream tube and passage are formed so that the total pressure drop in the whole system is the minimum. The effects of the apparent angle of repose between two layers, the packing volume and the passage resistance on the non-uniform flow in the layer were evaluated on the basis of the model. The result calculated by the approximate analysis agrees with the result by the numerical analysis based on the equations of continuity and of motion within ...
1988-02-01
Advanced nanoscale separations and mass spectrometry for sensitive high-throughput proteomics
Energy Technology Data Exchange (ETDEWEB)
We review recent development in separations and mass spectrometric instrumentation for sensitive and high-throughput proteomic analyses. These efforts have been primarily focused on the development of high-efficiency (separation peak capacity of ~103) nanoscale liquid chromatography (nanoLC; e.g., flow rates extending down to ~20 nL/min at optimal separation linear velocities through narrow packed capillaries) in combination with advanced mass spectrometry (MS), including high sensitivity and high resolution Fourier transform ion cyclotron resonance (FTICR) MS. This technology enables MS analysis of low nanogram-level proteomic samples (i.e., nanoscale proteomics) with individual protein identification sensitivity at the low zeptomole-level. The resultant protein measurement dynamic range can reach 106 for nanogram-sized proteomic samples, while more abundant proteins can be detected from complex sub-picogram size proteome samples. The average proteome ...
2005-06-01
A quantitative structural analysis of the low temperature phase of lithium-7
International Nuclear Information System (INIS)
Calculations in "7Li have been carried out for the differential coherent elastic scattering cross-section of thermal neutrons at a fixed scattering angle #theta#_0(148"o) and varying the energy of incident neutrons (or corresponding d-spacings). The results are reported, as variations of the ratio #SIGMA#_0"c"o"h (#theta#_0, d)/#SIGMA#_0"c"o"h (#theta#_0) with d-spacing, at atmospheric pressure and at two temperatures, 80 and 20 K. The calculations at 80 K correspond to BCC lithium whereas at 20 K all the possible crystallographic structures of polytype lithium (BCC, 9R, HCP and FCC) were considered. On comparing our results with the time-of-flight (TOF) measurements of Berliner et al. (Physical Review, B40, 12086, 1989) we find that up to 80 K lithium-7 does not undergo any martenistic transformation whereas the structural state at 20 K can be described by the co-existence of the original BCC phase with 9R, HCP and FCC closed packed structures. A quantitative ...
(Packaging regulations for chemical explosives)
Energy Technology Data Exchange (ETDEWEB)
The purpose of the trip was to visit Nobel Chemicals in Sweden and to confer with the Department of Transportation personnel in Sweden and in England on the technical and regulatory problems in the bulk shipping of the high explosives RDX and HMX. It is customary in the United States (US) to add isopropyl alcohol to the bulk shipment of water-wet high explosives RDX and HMX. The explosives are packed in cloth bags which are placed in plastic-lined fiber drums. The addition of alcohol presumably prevents mildewing of cloth bags and freezing of the wet explosives in cold weather. In Europe, however, these explosives are shipped in polyethylene-lined fiber drums with not less than 15% water only, even in cold weather. Water-wet frozen explosives have not proved to be any more sensitive than its unfrozen counterpart and no mildew problem has been encountered. It looks promising that the US Department of Transportation regulations can be changed to permit the bulk ...
1988-02-17
International Nuclear Information System (INIS)
In the third millennium, when the main words are globalization, world net of computers, genetic code and efficiency, deep transformations have been incorporated to human behavior. Among such transformations it may be pointed out, matching with the objectives of this study, the modem consumer's profile. The consumers have quickly become more and more conscious and demanding regarding to the quality of the available products in the market. In that sense, the consumer's concern about the natural and healthy appearance, as well as the preservation of the nutritious content of the foods, have been a constant sign of alert for producers and suppliers. Besides, the timeless for domestic preparation of foods have imposed the use of minimally processed as an incontestable reality. A barrier for the production of minimally processed foods is imposed by the degree of perishability of certain products, such as the cassava-parsley. This vegetable is a source of energy, calcium, phosphorus and ...
The metrology of the LHC project: what news?
Energy Technology Data Exchange (ETDEWEB)
The Large Hadron Collider (LHC), under construction at CERN, uses superconducting magnets operating at a temperature of 1.9 K to guide the circulating particles. A specific feature of the main magnets (dipoles and quadrupoles) is the two-in-one design with two magnetic channels in one common retaining structure. Indeed, the accelerator is made of two rings, mechanically linked, that have to be simultaneously aligned during the installation in the already existing LEP tunnel. The assembly tolerances of the LHC main magnets have been reconsidered to take into account the tight constraints on geometry. The dipoles are bent to follow closely the curvature of the circulating particles and to make a larger mechanical aperture available for the circulating particles. In order to minimise the geometrical errors the dipole assembly procedure is assisted by high precision survey measurements based on laser trackers. By this we hope to reduce to {+-} 1 mm the positioning ...
1999-07-01
The Next Linear Collider: NLC2001
Energy Technology Data Exchange (ETDEWEB)
Recent studies in elementary particle physics have made the need for an e{sup +}e{sup -} linear collider able to reach energies of 500 GeV and above with high luminosity more compelling than ever [1]. Observations and measurements completed in the last five years at the SLC (SLAC), LEP (CERN), and the Tevatron (FNAL) can be explained only by the existence of at least one particle or interaction that has not yet been directly observed in experiment. The Higgs boson of the Standard Model could be that particle. The data point strongly to a mass for the Higgs boson that is just beyond the reach of existing colliders. This brings great urgency and excitement to the potential for discovery at the upgraded Tevatron early in this decade, and almost assures that later experiments at the LHC will find new physics. But the next generation of experiments to be mounted by the world-wide particle physics community must not only find this new physics, they must find out what it ...
2002-01-14
Selection and design of ion sources for use at the Holifield radioactive ion beam facility
Energy Technology Data Exchange (ETDEWEB)
The Holifield Radioactive Ion Beam Facility now under construction at the Oak Ridge National Laboratory will use the 25 MV tandem accelerator for the acceleration of radioactive ion beams to energies appropriate for research in nuclear physics; negative ion beams are, therefore, required for injection into the tandem accelerator. Because charge exchange is an efficient means for converting initially positive ion beams to negative ion beams, both positive and negative ion sources are viable options for use at the facility. The choice of the type of ion source will depend on the overall efficiency for generating the radioactive species of interest. Although direct-extraction negative ion sources are clearly desirable, the ion formation efficiencies are often too low for practical consideration; for this situation, positive ion sources, in combination with charge exchange, are the logical choice. The high-temperature version of the CERN-ISOLDE positive ion source has ...
1994-06-01
PKU-RBRC Workshop on Transverse Spin
Energy Technology Data Exchange (ETDEWEB)
Understanding the structure of the nucleon is a fundamental question in subatomic physics, and it has been under intensive investigation for the last several years. Modern research focuses in particular on the spin structure of the nucleon. Experimental and theoretical investigations worldwide over the last few decades have established that, contrary to nave quark model expectations, quarks carry only about 30% of the totd spin of the proton. The origin of the remaining spin is the key question in current hadronic physics and also the major driving forces for the current and future experiments, such as RHIC and CEBAF in US, JPARC in Japan, COMPASS at CERN in Europe, FAIR at GSI in Germany. Among these studies, the transverse-spin physics develops actively and rapidly in the last few years. Recent studies reveal that transverse-spin physics is closely related to many fundamental properties of the QCD dynamics such as the factorization, the non-trivial universality ...
2008-06-30
Investigation of the dc vacuum breakdown mechanism
Breakdowns occurring in rf accelerating structures will limit the ultimate performance of future linear colliders such as the Compact Linear Collider (CLIC). Because of the similarity of many aspects of dc and rf breakdown, a dc breakdown study is underway at CERN to better understand the vacuum breakdown mechanism in a simple setup. Measurements of the field enhancement factor ? show that the local breakdown field is constant and depends only on the electrode material. With copper electrodes, the local breakdown field is around 10.8GV/m, independent of the gap distance. The ? value characterizes the electrode surface state, and the next macroscopic breakdown field can be well predicted. In breakdown rate experiments, where a constant field is applied to the electrodes, clusters of consecutive breakdowns alternate with quiet periods. The occurrence and lengths of these clusters and quiet periods depend on the evolution of ?. The application of a high field can even ...
2009-09-01
Deploying perfSONAR-based End-2-End monitoring for production US CMS networking
Energy Technology Data Exchange (ETDEWEB)
Fermilab is the US Tier-1 Center for CMS data storage and analysis. End-2-End (E2E) circuits are utilized to support high impact data movement into and out of the Tier-1 Center. E2E circuits have been implemented to facilitate the movement of raw experiment data from the Tier-0 Center at CERN, as well as processed data to a number of the US Tier-2 sites. Troubleshooting and monitoring of those circuits presents a significant challenge, since the circuits typically cross multiple research & education networks, each with its own management domain and customized monitoring capabilities. The perfSONAR Monitoring Project was established to facilitate development and deployment of a common monitoring infrastructure across multiple network management domains. Fermilab has deployed perfSONAR across its E2E circuit infrastructure and enhanced the product with several tools that ease the monitoring and management of those circuits. This paper will present the current ...
2007-09-01
Deformation change in light iridium nuclei from laser spectroscopy
International Nuclear Information System (INIS)
Laser spectroscopy measurements have been performed on neutron-deficient and stable Ir isotopes using the COMPLIS experimental setup installed at ISOLDE-CERN. The radioactive Ir atoms were obtained from successive decays of a mass-separated Hg beam deposited onto a carbon substrate after deceleration to 1kV and subsequently laser desorbed. A three-color, two-step resonant scheme was used to selectively ionize the desorbed Ir atoms. The hyperfine structure (HFS) and isotope shift (IS) of the first transition of the ionization path 5d"76s"2"4F_9_/_2#->#5d"76s6p"6F_1_1_/_2 at 351.5nm were measured for "1"8"2"-"1"8"9Ir, "1"8"6Ir"m and the stable "1"9"1","1"9"3Ir. The nuclear magnetic moments #mu#_I and the spectroscopic quadrupole moments Q_s were obtained from the HFS spectra and the change of the mean square charge radii from the IS measurements. The sign of #mu#_I was experimentally determined for the first time for the masses 182#=#+0.2 for the lighter group ...
2006-12-01
Accelerator technology program. Progress report, April-December 1978
This report presents highlights of activities in the Acceleartor Technology (AT) Division from April through December 1978. The report is divided into 10 sections to cover work done by the four groups that make up AT Division (AT-1, AT-2, AT-3, and AT-4). Section I is a brief summary of the whole report. Sections II through VI describe work done by At-1, the Linac Technology Group. Subjects covered are the Pion Generation for Medical Irradiation Program, the Electronuclear Fuel-Producing Accelerator Program, the Gyrocon rf Amplifier Program, the Electron Linear Accelerator Program, and the Free Electron Laser Program. Section VII covers the Linear Accelerator Beam Dynamics development, and Sec. VIII deals with work with the H/sup -/ Ion Source. Most of the work in Secs. VII and VIII was done by AT-2, the Special Projects Group, although work on factors influencing emittance growth was done by MP-9, and results on emittance growth in the new European Council for Nuclear Research ...
1980-05-01
Nuclear charge radii of light isotopes based on frequency comb measurements
Energy Technology Data Exchange (ETDEWEB)
Optical frequency comb technology has been used in this work for the first time to investigate the nuclear structure of light radioactive isotopes. Therefore, three laser systems were stabilized with different techniques to accurately known optical frequencies and used in two specialized experiments. Absolute transition frequency measurements of lithium and beryllium isotopes were performed with accuracy on the order of 10{sup -10}. Such a high accuracy is required for the light elements since the nuclear volume effect has only a 10{sup -9} contribution to the total transition frequency. For beryllium, the isotope shift was determined with an accuracy that is sufficient to extract information about the proton distribution inside the nucleus. A Doppler-free two-photon spectroscopy on the stable lithium isotopes {sup 6,7}Li was performed in order to determine the absolute frequency of the 2S {yields} 3S transition. The achieved relative accuracy of 2 x 10{sup -10} is improved by one ...
2010-02-11
Deformation change in light iridium nuclei from laser spectroscopy
Energy Technology Data Exchange (ETDEWEB)
Laser spectroscopy measurements have been performed on neutron-deficient and stable Ir isotopes using the COMPLIS experimental setup installed at ISOLDE-CERN. The radioactive Ir atoms were obtained from successive decays of a mass-separated Hg beam deposited onto a carbon substrate after deceleration to 1kV and subsequently laser desorbed. A three-color, two-step resonant scheme was used to selectively ionize the desorbed Ir atoms. The hyperfine structure (HFS) and isotope shift (IS) of the first transition of the ionization path 5d{sup 7}6s{sup 24}F{sub 9/2}{yields}5d{sup 7}6s6p{sup 6}F{sub 11/2} at 351.5nm were measured for {sup 182-189}Ir, {sup 186}Ir{sup m} and the stable {sup 191,193}Ir. The nuclear magnetic moments {mu}{sub I} and the spectroscopic quadrupole moments Q{sub s} were obtained from the HFS spectra and the change of the mean square charge radii from the IS measurements. The sign of {mu}{sub I} was experimentally determined for the first time for ...
2006-12-15
International Nuclear Information System (INIS)
A multielement apparatus for the removal of aerosols formed in the vitrification of simulated high-activity accident wastes from the decommissioned nuclear power plant A-1 has been designed, manufactured and tested. The apparatus consists of two cooling and condensing steps connected in series, and of five filtration steps also connected in series. The five filtration steps allowed to achieve a decontamination factor of 1x10"5 in the case of removal of a NaCl("2"4Na) testing model aerosol. The decontamination factor for removal of the cesium aerosol by the whole apparatus was 3.3x10"6. In the first filtration step the aerosols are removed by the cartridge with a filtration fabric made of polyethylene fibers, in the second step by the cartridge with a granulated natural material, in the third step by the cartridge with glass-fiber filtration paper, in the fourth and fifth steps by the cartridge with high-efficiency filtration paper made of glass microfibers. In the tube connecting the ...
A liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of the 10 major components of Da-Cheng-Qi decoction (rhein, emodin, aloe-emodin, chrysophanol, rheochrysidin, naringin, naringenin, hesperidin, magnolol and honokiol) in dog plasma. Plasma samples were spiked with internal standard (ibuprofen), acidified with HCl and extracted twice by liquid-liquid extraction using ethyl acetate. Separation was performed on a YMC-Pack ODS-A C(18) column (5 microm, 150 mm x 4.6 mm) and a C(18) guard column (5 microm, 4.0 mm x 2.0 mm) with methanol-water (92:8, v/v) at a flow rate of 0.3 mL/min. The LC/MS system was operated under the multiple reaction monitoring mode using electrospray ionization in the negative ion mode. All analytes showed good linearity over a wide concentration range (r>0.99). The linear range of the calibration curves was 5000-19.53 ng/mL for rhein; 400-3.13 ng/mL for emodin; 800-3.13 ng/mL ...
2009-05-21
SOLVENT EXTRACTION OF CESIUM BY DIPICRYLAMINE. III. SEMIWORKS DEMONSTRATION
The extraction and recovery of cesium from simulated Purex waste solutions was successfully demonstrated in the pilot plant pulse column. Stable volumetric capacities as high as 670 gph/ft/sup 2/ (sum of both phases) were obtained for alkaline supernate-type waste; however, for efficient operation (transfer unit height - HTU -of two feet or less), the maximum throughput rate was limited to about 500 gph/ft/sup 2/. This rate could be achieved with feeds diluted to densities within 0.08 g/cc of the solvent density. Stable feed was prepared from simulated current, denitrated waste by addition of citric acid to complex the iron before neutralization to the desired operating pH of 7 to 8. Capacities of 500 gph/ft/sup 2/ were readily achieved with this feed, together with HTU's of 1.0 to 1.3 feet. Sodium extracted with the cesium was satisfactorily scrubbed from the solvent with a dilute citric acid solution. Scrub section sodium decontamination factors ...
1963-03-15
Energy Technology Data Exchange (ETDEWEB)
Silicon on insulator (SOI) structures are promising candidates for the fabrication of VLSI circuits with very high packing densities. The preparation of such structures can now be achieved by high dose implantation of reactive ion species such as oxygen to produce buried layers of SiO/sub 2/ in silicon. In this paper we report experiments to depth profile these layered structures by SIMS. SOI samples have been prepared by implanting (100) silicon wafers with 400 keV molecular oxygen ions at a dose of 1.8x10/sup 18/ O/sup +/ cm/sup -2/. During the implantation the wafers were maintained at temperatures between 325 and 600/sup 0/C, using beam heating, which achieved in situ-annealing and ensured that the top silicon layer remained single crystal. Analysis was carried out on an Atomika DIDA-II spectrometer using 10 keV Ar/sup +/ ions with a low current density of less than 1 mA cm/sup -2/. During analysis negative secondary ions were monitored which provided a high ...
1983-12-15
Energy Technology Data Exchange (ETDEWEB)
This paper describes research and development activities at the University of Regina, Saskatchewan, Canada on Optimization of CO{sub 2} Extraction Process Technologies. The ultimate goal of this research is to develop better and more effective CO{sub 2} separation processes which can be used to recover CO{sub 2} from industrial sources such as coal-fired power plants and coal gasification complexes at the lowest possible capital and operating costs. The research program has been supported by Saskatchewan Power Corporation, Saskatchewan Energy and Mines, Prairie Coal Ltd., the Canada Centre for Mineral and Energy Technology (CANMET), Fluor Daniel Inc. (USA), Sulzer Chemtech (Switzerland), Wascana Energy Inc., and Natural Sciences and Engineering Research Council of Canada (NSERC). Currently, six parallel and complementary projects have been carried out at the Process Systems Laboratory. These projects are: (1) Searching for new sterically hindered amines for high capacity absorption of ...
1996-05-01
Energy Technology Data Exchange (ETDEWEB)
Spherical {beta}-Ni(OH){sub 2} was modified by a low-cost method of normal ball milling (NBM), and the physical properties of both ball-milled and un-milled Ni(OH){sub 2} were characterized by transmission electron microscopy, specific surface area, particle size distribution and X-ray diffraction. It was found that NBM could obviously increase the surface area, decrease the particle and crystallite size, and reduce the crystallinity of {beta}-Ni(OH){sub 2}, which were advantageous to the improvement of the electrochemical activity of Ni(OH){sub 2}. NBM also lowered the packing density and flowability of Ni(OH){sub 2}, as revealed by the measurements of tapping density and angle of repose. Electrochemical performances of pasted nickel electrodes with an addition of ball-milled Ni(OH){sub 2} to spherical Ni(OH){sub 2} as the active material were investigated, and were compared with those of the pure spherical Ni(OH){sub 2} electrodes. Charge/discharge tests showed ...
2006-09-15
Energy Technology Data Exchange (ETDEWEB)
The overall goal of the proposed project is to explore the use of partitioning tracers to characterize dense nonaqueous phase liquids (DNAPLs) in aquifer systems. Bulk-phase partitioning tracers will be investigated to detect and determine DNAPL saturation, while interface partitioning tracers will be investigated to measure the area of the DNAPL-water interface. The specific objectives that will be addressed to accomplish this goal are: (1) Investigate the use of partitioning tracers to detect and determine both the saturation and interfacial area of DNAPLs in saturated porous media. (2) Investigate the effect of rate-limited mass transfer on the transport behavior of partitioning tracers. (3) Investigate the effect of porous-media heterogeneity on the transport behavior of partitioning tracers. (4) Develop and evaluate mathematical models capable of simulating the transport of partitioning tracers in complex systems. This proposal outlines an integrated approach for the development ...
2000-09-14
PNC`s proposal on the Advanced Fuel Recycle concept
Energy Technology Data Exchange (ETDEWEB)
MOX fuel for FBR is allowed to contain impurities within several thousand ppm, which means less than 1000 of decontamination factor (DF) in reprocessing is enough for Pu and U recycle use. The Advanced Fuel Recycle proposed by PNC is on this basis. The concept consists of innovations on both MOX fuel fabrication and aqueous reprocessing technologies based on the Purex process and it is believed that successful optimization of fuel cycle interface condition is the key issue to realize the concept. The lower DF such as 1000 can be easily obtained by the simplified Purex flowsheet which has no purification steps. However, new subject arises in MOX fuel fabrication, that is, fabrication is conducted in the shielding cell using equipment which is maintained remotely. A simplified fabrication technology becomes essential to establish the remote maintenance system and is one of the critical path for achieving the Advanced Fuel Recycle. The PNC`s proposal on the advanced fuel recycle concept ...
1998-03-01
Off-gas behavior in the Harvest pot vitrification process
Energy Technology Data Exchange (ETDEWEB)
The conversion of highly radioactive waste liquor into glass by the pot vitrification process has been studied at Harwell using a full-scale inactive pilot plant. A summary of the off-gas behavior and its interpretation is presented. Experimental runs were carried out on 3 representative wastes (MAGNOX - thermal reactor, metal fuel, THORP - thermal oxide fuel and PFR - fast reactor oxide fuel) using 2 methods of feeding the glass-formers (slurry and crizzle). Materials were carried over from the vitrification vessel into the off-gas system by entrainment supplemented by volatilization. The overall behavior of the off-gas was consistent with the presence in it of 5 separate aerosols of particulate matter. Sources of entrainment gave rise to 3 aerosols, and a further 2 aerosols were formed as a result of chemical reaction (Ru) and condensation (Cs) processes involving the volatile species. Entrainment was enhanced when the feed contained free alkali nitrate. The Ru volatility correlated ...
1983-06-01
Off-gas behavior in the HARVEST pot vitrification process
Energy Technology Data Exchange (ETDEWEB)
A summary of the off-gas behavior in the HARVEST pot vitrification process is presented. Experimental runs were carried out on 3 representative wastes (MAGNOX - thermal reactor, metal fuel, THORP - thermal oxide fuel and PFR - fast reactor oxide fuel) using 2 methods of feeding the glass-formers (slurry and crizzle). Materials were carried over from the vitrification vessel into the off-gas system by entrainment supplemented by volatilization. The main volatile elements were Ru, B, Cs. Some volatility was also shown by Na and Li. The overall behavior of the off-gas was consistent with the presence in it of 5 separate aerosols of particulate matter. Sources of entrainment gave rise to 3 aerosols, and a further 2 aerosols were formed as a result of chemical reaction (Ru) and condensation (Cs) proceses involving the volatile species. Entrainment was enhanced when the feed contained free alkali nitrate. The Ru volatility correlated directly with the amount of salt nitrates in the feed. The ...
1983-06-01
New approaches to the design of the combustion system for thermophotovoltaic applications
Energy Technology Data Exchange (ETDEWEB)
A thermophotovoltaic (TPV) generator for electric vehicles has been designed and developed. In this paper we focus on the combustion system and the heat regenerator. The system has been designed to work as a range extender for electric vehicles. This solution would provide energy always available on the vehicle, which would run even if the battery level were low. Several configurations for the burner and for the heat exchanger have been investigated and a comparison of these is presented. The different solutions have been studied both theoretically and experimentally. In this paper, we report on the work carried out to build a TPV device capable of yielding 6 kW of electric power to recharge the battery pack of an electric city-car. The project has been divided into four steps: (1) pre-design of different configurations of the burner and heat exchanger using non-commercial software 'TPV Design Tool 1.0'; (2) testing of the pre-designed generators ...
2003-05-01
Energy Technology Data Exchange (ETDEWEB)
A Norwegian Research Program on Improved Oil Recovery (IOR) in North Sea reservoirs was launched in 1992. Microbial methods, applied in this context, is a part of this program. The scope, the methodological approach, and results from the three first years are presented. Water profile control, using biomass to block high permeable zones of a reservoir, has been investigated using nitrate-reducing bacteria in the injected sea water as plugging agents. Emphasis has been put on developing a process that does not have disadvantages secondary to the process itself, such as souring and impairment of the overall injectivity of the field. Data from continuous culture studies indicate that souring may successfully be mitigated by adding nitrite to the injected seawater. The morphology and size of generic-nitrate-reducing seawater bacteria have been investigated. Screening of growth-promoting nutrients has been carried out, and some sources were detected as favorable. Transport and penetration of ...
1995-12-31
Energy Technology Data Exchange (ETDEWEB)
In 1991/1992, VEAG decided to convert its 500 MW plants at Jaenschwalde and Boxberg to the latest state of technology. This even included the discharge of the cleaned flue gas through the existing cooling towers. The site of the flue gas desulphurization plant and also the existing cooling tower shells required routeing of the clean gas lines similar to the routes in the existing plants of RWE. The positive experience accrued with the pipework material `glass-fibre reinforced vinyl ester resin` has also led to the selection of this material here. The universally positive experience gained from existing clean gas lines via cooling towers by very different power station operators induced VEAG and its partners also to equip new construction operations in the new Federal states with this technology. (orig.) [Deutsch] In den Jahren 1991/1992 entschloss sich die VEAG, ihre 500-MW-Anlagen Jaenschwalde und Boxberg auf den neuesten Stand der Technik umzuruesten. Hierzu gehoerte auch die ...
1997-06-01
Energy Technology Data Exchange (ETDEWEB)
Environmental and breathing zone samples were analyzed for formaldehyde at the Pikes Peak Dialysis Center, Colorado Springs, Colorado in August, 1984 and February, 1985. The evaluation was requested by a representative of the Center to determine if there was a health hazard due to formaldehyde. Eight employees were interviewed. The ventilation systems were investigated. Personal protective clothing was inspected. Breathing-zone samples contained 0 28 to 1.0 (mg/m/sup 3/) formaldehyde. The OSHA standard for formaldehyde is 3.7 mg/m/sup 3/. Area formaldehyde concentrations ranged from nondetectable to 0.75 mg/m/sup 3/. Health complaints reported included sore throat, congestion, cough, and eye, nose and throat irritation. Most of the complaints originated from employees in the formalin mixing, reuse sterilization, and dialysis unit packing sections. The exhaust system in the reuse sterilization area was not working efficiently. A variety of personal protective ...
1985-08-01
International Nuclear Information System (INIS)
This present study evaluated the effect of gamma radiation on the fungal survival in packed medicinal plants, purchased from wholesale and retail market, in different period (0 and 30 days) after the treatment. Five kind of medicinal plants (Peumus boldus, Camellia sinensis, Maytenus ilicifolia, Paullinia cupana and Cassia angustifolia), were collected from different cities of Sao Paulo State, and submitted to irradiation treatment using a 60Co source (type Gammacell 220) with doses of 5,0 kGy and 10 kGy and at dose rate of 3.0 kGy/h. Non-irradiated samples (control group) were used for fungal counts and serial dilutions from 10-1 to 10-6 of the samples were seeded in duplicates and plated using the surface culture method in Dichloran 18% Glycerol Agar (DG 18) and were counted after five days at 25 deg C. The control group revealed the presence of genera Aspergillus and Penicillium, which are known as toxigenic fungi and a few samples of control group were within ...
2006-12-20
Electronic and geometric structure of transition-metal nanoclusters
Energy Technology Data Exchange (ETDEWEB)
A massively-parallel ab initio computer code, which uses Gaussian bases, pseudopotentials, and the local density approximation, permits the study of transition-metal systems with literally hundreds of atoms. We present total energies and relaxed geometries for Ru, Pd, and Ag clusters with N = 55, 135, and 140 atoms; we also used the DMOL code to study 13-atom Pd and Cu clusters, with and without hydrogen. The N = 55 and 135 clusters were chosen because of simultaneous cubo-octahedral (fcc) and icosahedral (icos) sub-shell closings, and we find icos geometries are preferred. Remarkably large compressions of the central atoms are observed for the icos structures (up to 6% compared with bulk interatomic spacings), while small core compressions ({approx} 1 %) are found for the fcc geometry. In contrast, large surface compressive relaxations are found for the fcc clusters ({approx} 2-3% in average nearest neighbor spacing), while the icos surface displays small compressions ({approx} 1%). ...
1996-08-01
Effects of reactor configuration on the performance of static-bed submerged media anaerobic reactors
Energy Technology Data Exchange (ETDEWEB)
Three different configurations of cylindrical submerged media anaerobic reactors (SMARs) with packing volumes of 85 items were operated at 35 C for 415 days with COD loading rates varying from 1 to 12 g/l/d and three retention times of 0.5, 1, and 2 days. A synthetic waste consisting of a milk solution with a mineral supplement was used for the feed. Tracer studies on clean-bed and dirty-bed SMARs indicate that reactor configuration, biogas mixing, and biomass accumulation all have a significant effect on SMAR hydraulics and cause short-circuiting. Based on the isothermal energy dissipation theory, the higher hydrostatic pressures resulting from higher SMAR heights increases self-induced biogas mixing and improves the contact efficiency between substrate and organisms. Based on TCOD removal rate, the tallest SMAR performed slightly better at COD loading rates above 4/g/l/d. At COD loading rates equal to or below 4 g/l/d, there was little difference in TCOD removal ...
1988-01-01
Adsorption of ethylene and ethane on graphitized thermal carbon black and in slit pores whose walls are composed of graphene layers is studied in detail to investigate the packing efficiency, the two-dimensional critical temperature, and the variation of the isosteric heat of adsorption with loading and temperature. Here we used a Monte Carlo simulation method with a grand canonical Monte Carlo ensemble. A number of two-center Lennard-Jones (LJ) potential models are investigated to study the impact of the choice of potential models in the description of adsorption behavior. We chose two 2C-LJ potential models in our investigation of the (i) UA-TraPPE-LJ model of Martin and Siepmann for ethane and Wick et al. for ethylene and (ii) AUA4-LJ model of Ungerer et al. for ethane and Bourasseau et al. for ethylene. These models are used to study the adsorption of ethane and ethylene on graphitized thermal carbon black. It is found that the solid-fluid binary interaction ...
2004-12-01
Diagnostic and Therapeutic RI Generators
Energy Technology Data Exchange (ETDEWEB)
Different types of generators have been developed for the convenient use of {sup 99m}Tc as the demand for this radioisotope is strong. Currently, the demand for {sup 99m}Tc is more than 80 % of the total demand for medical isotopes in the world. A {sup 99m}Tc generator, in general, is composed of a column packed with ceramic adsorbent, tubing, eluent reservoir or vials, collection vials, and shielding. The key technology to develop a good generator is how to load {sup 99}Mo as much as possible while maintaining the quality of eluted {sup 99}mTc as good as possible. The technology is well developed and already available commercially for the case of the fission {sup 99}Mo/{sup 99}mTc because loading of few curries of {sup 99}Mo on a conventional adsorbent, i.e. alumina is not a serious task in the chemical point of view. However, the current infrastructure of the supply of {sup 99}Mo to the world market is sturdy as the research reactors are getting aged. In this ...
2006-07-01
Energy Technology Data Exchange (ETDEWEB)
This report investigates methods to utilize existing bulk tobacco kilns for curing (drying) of shelled corn, peanuts, and baled hay. In recent years Ontario tobacco producers have had to reduce production levels due to a declining demand for flue-cured tobacco. Many tobacco producers are currently diversifying into other crops. Some of these crops require curing and/or storage. Because of high capital costs to purchase conventional curing and/or storage facilities, tobacco producers wish to reduce their initial diversification costs by modifying their existing tobacco kilns (tobacco drying structures) and/or tobacco storage barns for this purpose. The investigation included high profile and low profile downdraft stick kilns, bulk kilns, and tobacco storage (pack) barns. Corn, peanuts, and hay were considered in relation to bulk kiln specifications and modifications, handling, drying and storage methods, energy requirements, cost, and quality of end product. The ...
1988-01-01
Energy Technology Data Exchange (ETDEWEB)
For large transmission steel towers to be built in a mountainous area, caisson type pile foundations are often applied. The works for construction of this kind of foundation are manned operations such as drilling, arranging reinforcements, concrete laying, etc. in a narrow vertical pit which is 3m in diameter and about 20m in depth, but securing labour force of good quality for such works becomes increasingly difficult. In order to cope with the above situation and achieve reduction of costs, shortening of construction period, improvement of safety, saving of manpower, etc. a power supply company and construction companies have developed jointly a method of unmanned construction in a caisson type pile foundation pit. This method consists of the use of a caisson type pile full size excavator (this consists of an excavator proper, a vacuum soil discharging device, a monitor/controller, a load crane and a reaction pad, and performs continuously unmanned operations in a pit of fullsize ...
1996-06-25
Development of a microbiological ammonium to nitrate recycling bioreactor for space capsules
International Nuclear Information System (INIS)
Since 1988, the Expertise group of Molecular and Cellular Biology (MCB) is an important partner in the development of the Micro-Ecological Life Support System Alternative (MELiSSA). The MELiSSA was designed to allow a small crew to survive on an Antarctic, lunar or Mars outpost, and is a joint research project currently fostered by the European Space Agency, ESA. The MELiSSA functions through a series of five interconnected compartments, of which four are microbial bioreactors and was engineered to degrade organic waste, regenerate the outpost's atmosphere and water, and provide the crew with an additional vegetarian diet. The bioreactor of the third compartment provides the edible cyanobacteria and plants of the fourth compartment with nitrate instead of ammonium as a source of nitrogen. The two bacteria responsible for the biological transformation of ammonium to nitrate (nitrification) are Nitrosomonas europaea and Nitrobacter winogradskyi. Since all MELiSSA-reactors are to be ...
2009-09-01
Determination of sodium in biological samples by instrumental neutron activation analysis
International Nuclear Information System (INIS)
Sodium is one of the most essential elements needed for metabolic processes amongst human beings. It is consumed in the form of sodium chloride but it is also present in edible plant leaves. Sodium is mostly analyzed by flame photometric method, a destructive and time consuming technique. Sodium has been determined in some green leave vegetables samples-palak, radish, khatta palak (ambat chuka), chaulai leaves, chauli bean covers and its seeds by instrumental neutron activation analysis. The method involves irradiation of samples with thermal neutrons from "2"4"1Am-Be source and counting "2"4Na activity (half life 15 hr) from the reaction "2"3Na(n,#gamma#) "2"4Na. Activity due to 1.37 MeV photopeak was counted with a NaI(Tl) crystal coupled to gamma ray spectrometer. Green leaves of the vegetables were thoroughly washed, dried at constant temperature and powdered. Bowen's Kale powder was used as standard for measuring sodium abundances. About 2g each of samples and the standard were ...
1981-05-01
Energy Technology Data Exchange (ETDEWEB)
The burning characteristics of fuel droplets containing nano and micron-sized aluminum particles were investigated. Particle size, surfactant concentration, and the type of base fluid were varied. In general, nanosuspensions can last much longer than micron suspensions, and ethanol-based fuels were found to achieve much better suspension than n-decane-based fuels. Five distinctive stages (preheating and ignition, classical combustion, microexplosion, surfactant flame, and aluminum droplet flame) were identified for an n-decane/nano-Al droplet, while only the first three stages occurred for an n-decane/micron-Al droplet. For the same solid loading rate and surfactant concentration, the disruption and microexplosion behavior of the micron suspension occurred later with much stronger intensity. The intense droplet fragmentation was accompanied by shell rupture, which caused a massive explosion of particles, and most of them were burned during this event. On the contrary, for the ...
2011-02-15
CHEMICAL TECHNOLOGY DIVISION, UNIT OPERATIONS SECTION MONTHLY PROGRESS REPORT, JULY 1960
A critical review of the literature revealed no experiments on uranyl ion transfer from an aqueous to a tributyl phosphate phase which positively measured the kinetics of the chemical reaction at the interphase. Drawing isorhythmic lines on a three component diagram gives a complex correlation for the compaction of three sizes of glass beads. Neither the use of thoria sols nor high feed solution concentrations of thorium nitrate gave any significant increase in mean particle diameters over those obtained from nitrate solutions of lower concentrations in flame denitration. A hydraulic film resistance has been detected in the anion exchange of uranyl sulfate into Dowex 2lK, and chloride elution was found to give a higher apparent uranium diffusion coefficient than nitrate elution. The rate of dissolution of mixed thorium-uranium oxides was determined as a function of the per cent of mixed oxides dissolved. Mixing in tanks packed with ...
1960-10-27
Energy Technology Data Exchange (ETDEWEB)
The adsorption equilibria of Kr, Xe and N{sub 2}, which are constituents of the off-gas from nuclear reprocessing processes, on representative adsorbents (Molecular Sieve 5A (MS5A) and activated charcoal) were studied. Adsorption experiments were conducted in the temperature range of 77 to 323 K using a packed bed column. The adsorption isotherms for the activated charcoal adsorbent were successfully correlated by the vacancy solution model. The adsorption isotherms for the MS5A adsorbent were properly correlated by the Langmuir model and the vacancy solution model. The adsorption experiments for the binary component systems (Kr-Xe, Kr-N{sub 2} systems) were also performed, and the results suggest that the coexistence of Xe greatly inhibits the adsorption of Kr. The coexistence of large amounts of N{sub 2} was also found to inhibit the adsorption of Kr. The experimental results for the adsorption equilibrium of binary component systems on the activated charcoal ...
1999-09-01
International Nuclear Information System (INIS)
A gel-type "9"9Mo-"9"9"mTc generator using Titanium-Molybdate target (TiMo-target) as column packing was developed in Radioisotope Department, the Dalat Nuclear Research Institute [1]. The concentration of trace elements in TiMo-target and radionuclidic purity in "9"9"mTc solution eluted from this type of generator were studied for quality control purpose. The monostandard method in neutron activation analysis has been applied to determine the concentration of trace impurities in titanium-molybdate target. For neutron activation analysis, TiMo samples were irradiated in the different channels of nuclear reactor IVV-9 at a neutron flux of maximum 2.1 x 10"1"3 n.cm"-"2s"-"1. The following chemical element impurities were determined: Na, W, Co, Fe, Zn, Ag, Sb and Cr. The gamma ray emitted nuclides found in "9"9"mTc solution eluted from our "9"9"mTc generator were the following: "6"5Zn, "6"0Co, "1"1"0"mAg, "5"9Fe, "5"1Cr, "2"4Na, "8"2Br and "9"9Mo. "9"9Mo was found ...
2004-06-01
Energy Technology Data Exchange (ETDEWEB)
Particle shape is an important parameter in numerous civil, environmental, and petroleum engineering applications. In ground-water flow, the shape of individual particles comprising the soil affects the soil`s pore size distribution and, hence, the important flow characteristics such as hydraulic conductivity and headloss. A model for delineating the relative importance of particle size, particle shape, and porosity, (and their interactions), in explaining the variability of hydraulic conductivity of a granular porous medium is developed and tested. Three types of porous media are considered in this work: spherical glass beads; granular sand; and irregularly shaped, shredded glass particles. A reliable method for quantifying the three-dimensional shape and packing of large samples of irregular particles based on their angle of repose is presented. The results of column experiments indicate that in the size range examined (i.e., 149 {micro}m to 2,380 {micro}m), the ...
1995-11-01
International Nuclear Information System (INIS)
This paper discusses the structural and compositional changes at the nanometer scale associated with the nucleation and growth of #alpha# precipitates in the #beta# titanium alloy Ti-5553 (Ti-5Al-5Mo-5 V-3Cr-0.5Fe) with #omega# precipitates acting as heterogeneous nucleation sites. The microstructural evolution in this alloy, during #beta#-solutionizing, quenching and aging type heat-treatments, has been investigated by combining results from scanning electron microscopy, orientation imaging microscopy, transmission electron microscopy, high-resolution TEM and three-dimensional atom probe (3DAP) tomography. Athermal #omega# precipitates form in this alloy on quenching from above the #beta# transus temperature. On isothermal annealing at low temperatures, these #omega# precipitates coarsen to form chemically ordered #omega# precipitates, accompanied by the nucleation of the stable #alpha# phase. Annealing at higher temperatures leads to dissolution of #omega# and further growth of ...
2009-04-01
Energy Technology Data Exchange (ETDEWEB)
This study reports on the physical-chemical behaviour of swelling di-octahedral clays (smectites) and their interaction with aqueous solutions and bacteria (Shewanella putrefaciens). Experimental results are presented for compacted clays, hydrated under confined volume conditions, using a new type of reaction-cell (the 'wet-cell' of Warr and Hoffman, 2004) that was designed for in situ X-ray diffraction (XRD) measurement. For comparison, dispersed clay systems were studied using standard batch solutions subjected to varying degrees of agitation. The combination of time-dependent in situ XRD measurements with gravimetric measurements and calculated diffraction patterns using the CALCMIX software (Plancon and Drits, 1999) allowed to successful quantification of the dynamics of water uptake and storage. This analytical procedure combined with published water vapour adsorption data enabled determination of the abundance of structured water layers, developed in the ...
2008-01-15
Terra Nova: taming the North Atlantic
Energy Technology Data Exchange (ETDEWEB)
The Terra Nova offshore oil project is described, with emphasis on the construction of the Terra Nova Floating Production Storage and Offloading (FPSO) vessel, the first such vessel constructed for the harsh environment of the North Atlantic off Newfoundland, the site of an oil field that is expected to produce 125,000 to 150,000 barrels of oil per day starting in 2001. The vessel has a double-hull, made of 3,000 tons of reinforced steel to protect it from ice in the form of massive icebergs or crusty 'packs'. The vessel has the world's largest quick release turret, meaning that the vessel can be quickly disconnected from its turret and mooring in the event of an encroaching iceberg, and then reconnected in an environmentally sound way. Apart from its extremely rugged construction, protecting the FPSO vessel against icebergs is accomplished by way of 'hosing down' (by melting by powerful streams of water) or ...
2000-08-01
Pre-Flight Development of the PoGOLite Pathfinder
International Nuclear Information System (INIS)
The Polarized Gamma-ray Observer (PoGOLite) is a balloon-borne instrument that will measure gamma-ray polarization in the energy range 25-80 keV from astronomical sources such as pulsars, accretion discs and jets from active galactic nuclei. The two additional parameters provided by such observations, polarization angle and degree, will allow these objects to be studied in a new way, providing information about their emission mechanisms and geometries. The instrument measures azimuthal scattering angles of photons within a close packed array of phoswich detector cells (PDCs) based on coincident detection of Compton scattering and photoelectric absorption. Each PDC comprises three different scintillating components and combines photon detection, active collimation and bottom anticoincidence into one single unit. The three parts are viewed by a photomultiplier tube (PMT) and pulse shape discrimination is used to identify signals from dierent parts. Surrounding the ...
Interaction of antimicrobial peptides with lipid membranes
International Nuclear Information System (INIS)
This study aims to investigate the difference in the interaction of antimicrobial peptides with two classes of zwitterionic peptides, phosphatidylethanolamines (PE) and phosphatidylcholines (PC). Further experiments were performed on model membranes prepared from specific bacterial lipids, lipopolysaccharides (LPS) isolated from Salmonella minnesota. The structure of the lipid-peptide aqueous dispersions was studied by small-and wide-angle X-ray diffraction during heating and cooling from 5 to 85 C. The lipids and peptides were mixed at lipid-to-peptide ratios 10-10000 (POPE and POPC) or 2-50 (LPS). All experiments were performed at synchrotron soft condensed matter beamline A2 in Hasylab at Desy in Hamburg, Germany. The phases were identified and the lattice parameters were calculated. Alamethicin and melittin interact in similar ways with the lipids. Pure POPC forms only lamellar phases. POPE forms lamellar phases at low temperatures that upon heating transform into a highly curved ...
In-situ growth of porous alumino-silicates and fabrication of nano-porous membranes
Feasibility of depositing continuous films of nano-porous alumino-silicates, primarily zeolites and MCM-41, on metallic and non-metallic substrates was examined with an aim to develop membranes for separation of gaseous mixtures and also for application as hydrogen storage material. Mesoporous silica was deposited in-side the pores of these nano-porous disks with an aim to develop membranes for selective separations. Our study involves supported zeolite film growth on substrates using in-situ hydrothermal synthesis. Faujasite, Silicalite and Mesoporous silica have been grown on various metallic and non-metallic supports. Metallic substrates used for film growth included anodized titanium, sodium hydroxide treated Titanium, Anodized aluminum, and sintered copper. A non-metallic substrate used was nano-porous aluminum oxide. Zeolite film growth was characterized using Scanning Electron Microscope (AMRAY 1820) and High Resolution Transmission electron microscope. Silicalite was found to ...
2009-01-01
International Nuclear Information System (INIS)
Most countries have taken the vitrification route for managing High Level Waste (HLW). Depending on composition of site-specific HLW, suitable glass forming oxides are added to it in a melting furnace designed for converting the mixture to a matrix of borosilicate glass. After thorough homogenization, the product is poured into stainless steel canisters as an inert solidified form. Canisters are seal welded and 2-3 such containers are then packed and sealed in another bigger container for providing an additional engineered barrier. This product form is considered safe for long-term storage. The concurrent vitrification technologies employ either induction-heated metallic melters or joule-heated direct resistance-heated ceramic melters. In India, both technologies have been adopted. While older facilities in Trombay and Tarapur employ metallic melters, a retrofitted facility at Tarapur and the new plant at Kalpakkam are based on ceramic melter operations. Compared ...
Hydrologic Tests at Characterization Wells R-9i, R-13, R-19, R-22, and R-31
Energy Technology Data Exchange (ETDEWEB)
Hydrologic information is essential for environmental efforts at Los Alamos National Laboratory. Testing at new characterization wells being drilled to the regional aquifer (''R wells'') to improve the conceptual hydrogeologic model of the Pajarito Plateau is providing such information. Drilling has been by air-rotary casing-advance or open-hole methods. Most wells are completed with multiple screens. After their construction, wells were rigorously developed by wire-brushing, bailing, followed by surging, swabbing, or jetting, and finally by pumping. These methods are effective based on field-parameter measurements and comparison of results of hydrologic testing at well R-31 before and after complete well development. We conducted field tests on various zones of saturation penetrated by the R wells to collect data needed for determining hydraulic properties. This document provides details of the design and execution of testing as well as an analysis ...
2003-03-01
Aespoe Pillar Stability Experiment. Acoustic emission and ultrasonic monitoring
Energy Technology Data Exchange (ETDEWEB)
This report describes the results from acoustic emission (AE) and ultrasonic monitoring of the Aespoe Pillar Stability Experiment (APSE) at SKB's Hard Rock Laboratory (HRL), Sweden. The APSE is being undertaken to demonstrate the current capability to predict spalling in a fractured rock mass using numerical modelling techniques, and to demonstrate the effect of backfill and confining pressure on the propagation of micro-cracks in rock adjacent to deposition holes within a repository. An ultrasonic acquisition system has provided acoustic emission and ultrasonic survey monitoring throughout the various phases of the experiment. Results from the entire data set are provided with this document so that they can be effectively compared to several numerical modelling studies, and to mechanical and thermal measurements conducted around the pillar volume, in an 'integrated analysis' performed by SKB staff. This document provides an in-depth summary of the AE and ...
2005-12-15
40th Anniversary of the First Proton-Proton Collisions in the CERN Intersecting Storage Rings (ISR)
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