WorldWideScience
2

Proposed Network Security Policy for Integrated Tactical ...  

Science.gov (United States)

... MTR 93B0000095 Proposed Network Security Policy for Integrated Tactical Warning ... Proposed Network security Policy for Integrated Tactical ...

1993-09-01

3

A Secure and Efficient Communications Architecture for ...  

Science.gov (United States)

... Milstar Military Strategic and Tactical Relay Satellite ... (EHF) system, composed of the Military Strategic and Tactical Relay Satellite (Milstar) ...

2008-06-19

4

The ultrastructure of conjunctival melanocytic tumors.  

UK PubMed Central (United Kingdom)

The ultrastructure of conjunctival melanocytic lesions in 49 patients was evaluated to find significant differences between benign and malignant cells. The patients studied included 9 with benign epithelial...Full Text Available

1984-01-01

5

Battalion Tactical Plays--Can They Increase Combat Power  

Science.gov (United States)

... Tactical plays are more than drills or standard operating proc-edures. ... IN * BYPMASS OR BREECH MINEFIELD ON FLANK SIXE (TM I3A C1 10 ...

1988-11-10

6

A surface acoustic wave electric field strength meter for environmental studies of HV transmission lines  

International Nuclear Information System (INIS)

In recent years, there has been a significant increase in concern over the health and safety aspects of high voltage transmission lines (HVTL). The majority of research has focused on effects directly or indirectly involved with the central nervous system, including physiological, ultrastructural, and biochemical alterations, changes in blood composition, behaviour, reproduction, and development. Several recent epidemiological reports have presented preliminary data suggesting an increase in the incidence of cancer among children and adults exposed to magnetic fields through living close to various types of electrical power lines or devices. With the increase in environmental concerns there has been a concomitant consideration of biological effects and health implications related to presently existing HVTL and those planned in the future. It was concluded that the electric and magnetic field strengths and the electrical discharges are the most ...

1988-04-01

7

DOD (Department of Defense) Acquisition: Case Study of the MILSTAR (Military Strategic and Tactical Relay) Satellite Communications System.  

Science.gov (United States)

The study of the Military Strategic and Tactical Relay (MILSTAR) program focuses on the role of the program manager and contracting officer in developing the acquisition strategy.

1986-01-01

8

War and Escalation in South Asia  

Science.gov (United States)

... TTP tactics, techniques, and procedures UCP Unified ... be sold or transferred to Pakistan, pursuant to ... substantial amounts of those funds being spent ...

2011-05-13

9

Technology Transfer. Volume 2  

Science.gov (United States)

... table (ASCAMP) system and the Military Strategic and Tactical Relay (Milstar) program. 10 ... Single Channel Antijam Milstar Portable Terminal ...

1992-04-01

10

Tactical Mobility Modeling for REFORGER 87  

Science.gov (United States)

... The SMSP makes predictions based on historical precipitation data, precipitation ... are characterized by relatively large areas of strategic interest. ...

1992-08-01

11

Report on Progress toward Security and Stability in ...  

Science.gov (United States)

... in tactics, techniques, and procedures (TTP), such as ... flow across the Afghanistan-Pakistan border, specifically ... The funds from the NATO ANA Trust ...

2009-10-01

12

NRL Fact Book 2010  

Science.gov (United States)

... Tactical Electronic Warfare Division (Code 5700) Visualization Laboratory Transportable step frequency radar Vehicle development laboratory ...

2011-05-15

13

NRL Fact Book  

Science.gov (United States)

... Tactical Electronic Warfare Division (Code 5700) Visualization Laboratory Transportable step frequency radar Vehicle development laboratory ...

2011-05-15

14

An Analysis of Small Navy Tactics Using a Modified Hughes' ...  

Science.gov (United States)

... APPENDIX A: A PROPOSED STAYING POWER MODEL .....73 A. INTRODUCTION .....73 B. PROPOSED STAYING ...

2007-03-01

15

Officer in Tactical Command and Tactical Data Information Exchange Systems (OTCIXS/TADIXS) and the Transition to the Military Strategic and Tactical Relay System (MILSTAR).  

Science.gov (United States)

The purpose of this thesis is to explore possible difficulties and their solutions in transitioning the OTCIXS/TADIXS subsystems from the present Navy UHF Fleetwide Satellite System to the EHF/SHF MILSTAR System. The research provides a description of the...

1987-01-01

16

How Do Police Respond to Stalking? An Examination of the Risk Management Strategies and Tactics Used in a Specialized Anti-Stalking Law Enforcement Unit  

British Library Electronic Table of Contents (United Kingdom)

How do police respond to and manage complaints of stalking? To answer this question, we conducted a 3-phase study. First, we reviewed the literature to identify risk management tactics used to combat stalking. Second, we asked a group of police officers to review those tactics for completeness and group them into categories reflecting more general risk management strategies. The result was 22 categories of strategies. Finally, we used qualitative methods to evaluate the files of 32 cases referred to the specialized anti-stalking unit of a metropolitan police department. We coded specific risk management tactics and strategies used by police. Results indicated that a median number of 19 specific tactics from 7 general strategies were used to manage risk. Also, the implementation of strategi...

2011-01-01

17

UGV Simulations and Modeling in a SIL Environment  

Science.gov (United States)

... UGV), in the air (UAV), or underwater (UUV) -across ... Figure 2 Tactical Mobile Robot MOUT concept: ... 10 robots to clear 20 rooms in 60 minutes ...

2011-05-14

18

The restructured Milstar program  

Science.gov (United States)

This paper discusses the restructure of the Milstar communication satellite program. The resulting system is substantially streamlined, and will provide better utilization by tactical forces without compromising strategic nuclear communications requirements.

1992-03-01

19

TNT Testbed for Self-Organizing Tactical Networking and ...  

Science.gov (United States)

... USMC-MCTSSA NIST NSWC-Dahlgren NAWC- CL TSWG Programs Utilizing TNT Testbed DARPA HURT ACTD DARPA MAV ACTD ...

2009-06-01

20

Report Out of the C4I Study Group  

Science.gov (United States)

... Tactical Electronic Intelligence (TACELINT), and a variety of other messages in US Message Text Format (USMTF) in both JANAP 128 and DOI 103 ...

2001-06-01

21

Operational Sustainment in an Immature Theater  

Science.gov (United States)

... of the 82nd Airborne Division and the 4th Marine Expeditionary Brigade. ... the 82nd Airborne Division, XVIII Airborne Corps and Tactical ...

1990-04-30

22

Increasing the Ground Tactical Mobility Of US Airborne Forces ...  

Science.gov (United States)

... public and civilian leadership considers the Insertion of the 82nd ... C+7, an airborne/light division by C+ 12, two heavy divisions by C+30, ...

1992-12-17

23

Exoplanet Community Report - Exoplanet Exploration Program - NASA  

Science.gov (United States)

the booms, separated by 12.5 m, deployed using the well proven MILSTAR hinge technology. ...... MILSTAR. Military Strategic and Tactical Relay satellite ...

24

DARPA's Airland Battle Management Program and USAF's ...  

Science.gov (United States)

... Accession Number : ADP005426. Title : DARPA's Airland Battle Management Program and USAF's Tactical Expert Mission Planner (TEMPLAR),. ...

1986-02-01

25

Characterization of polymers for microcellular foams  

Energy Technology Data Exchange (ETDEWEB)

We have measured, by {sup 1}H and {sup 13}C nuclear magnetic resonance (NMR), the percent deuteration, the tacticity and the purity of several polymers and one solvent used in the preparation of microcellular foams. The percent deuteration was measured for polystyrene, polyacrylonitrile and polyethylene. The tacticities of polystyrene and polyacrylonitrile were determined. The purity and degradation products of polyacrylonitrile and maleic anhydride were examined. This report documents the experimental procedures and results of these measurements.

1992-03-01

26

Evaluating technologies for tactical information management in net-centric systems  

Science.gov (United States)

Recent trends in distributed real-time and embedded (DRE) systems motivate the development of tactical information management capabilities that ensure the right information is delivered to the right place at the right time to satisfy quality of service (QoS) requirements in heterogeneous environments. A promising approach to building and evolving large-scale and long-lived tactical information management systems are standards-based QoS-enabled publish/subscribe (pub/sub) platforms that enable applications to communicate by publishing information they have and subscribing to information they need in a timely manner. Since there is little existing evaluation of how well these platforms meet the performance needs of tactical information management, this paper provides two contributions: (1) it describes three common architectures for the OMG Data Distribution Service (DDS), which is a QoS-enabled pub/sub platform standard, and ...

2007-05-01

27

Ultrastructural Evidence of Dermal Gadolinium Deposits in a Patient with Nephrogenic Systemic Fibrosis and End-Stage Renal Disease  

UK PubMed Central (United Kingdom)

Background and objectives: The pathogenesis of acquired nephrogenic systemic fibrosis recently described for patients with renal insufficiency and a history of exposition to gadolinium-based magnetic...Full Text Available

2008-07-01

28

Nitrogen nutrient status induces sexual differences in responses to cadmium in Populus yunnanensis  

UK PubMed Central (United Kingdom)

Populus yunnanensis was employed as a model species to detect sexual differences in growth, physiological, biochemical, and ultrastructural responses to cadmium (Cd) stress, nitrogen...Full Text Available

2011-10-01

29

Morphology and Ultrastructure of Maternal Seed Tissues of Soybean in Relation to the Import of Photosynthate  

UK PubMed Central (United Kingdom)

Cytological observations were made on developing seeds of soybean (Glycine max (L.) Merr. “Amsoy 71”) using scanning and transmission electron microscopy and light microscopy....Full Text Available

1981-05-01

30

Impact of physical training on the ultrastructure of midthigh muscle in normal subjects and in patients treated with glucocorticoids.  

UK PubMed Central (United Kingdom)

Exercise-training might be a logical method to reverse muscle atrophy and weakness in patients treated with glucocorticoids. The purpose of the present investigation was to establish whether a treatment...Full Text Available

1987-04-01

31

Cytochemical localisation and characterisation of proteoglycans (glycosaminoglycans) in the epithelial-stromal interface of the seminal vesicle of the guinea pig.  

UK PubMed Central (United Kingdom)

The proteoglycans (PGs) in the guinea pig seminal vesicle were demonstrated ultrastructurally by both cuprolinic blue (CB) and ruthenium red (RR) staining. The PGs appeared as electron-dense granules...Full Text Available

1992-02-01

32

Cogan's microcystic dystrophy of the cornea: ultrastructure and photomicroscopy.  

UK PubMed Central (United Kingdom)

Corneal biopsy specimens from 3 patients with Cogan's microcystic corneal dystrophy were examined by light and electron microscopy. Specimens were taken from corneas showing microcysts, geographic or...Full Text Available

1978-12-01

33

The skin of Osedax (Siboglinidae, Annelida): An ultrastructural investigation of its epidermis  

British Library Electronic Table of Contents (United Kingdom)

The symbiotic polychaetes of the genus Osedax living on the bones of whale carcasses have become known as bone-eating worms. It is believed that whale bones are the source of nutrition for those gutless worms and that fatty acids are produced by their symbionts and transferred to the host. However, the symbionts are of the heterotrophic group Oceanospirillales and as such are not able to synthesize organic carbon de novo. Also, they are not housed in close contact to the bone material. We studied the ultrastructure of the integument overlying the symbiont housing trophosome in the ovisac region and the roots region and of the symbiont-free trunk region of Osedax to investigate the hosts possible contribution in feeding for the whole symbiosis. The epidermis differs conspicuously between th...

2010-01-01

34

Tactical Breach Operations in Modern Warfare  

Science.gov (United States)

... t.., tt:,tifv! th - cui,nt !shor tfal 1 in breaching capAbiii tN wi h i- 1!,-ia . ~ ... Before the 1967 war, the Israeli Training ... trained Arab opponents. ...

1990-06-01

35

Synthesis of polyacrylonitrile (PAN) with different stereoregularity by urea radiation inclusion polymerization and its application to carbon fiber  

Energy Technology Data Exchange (ETDEWEB)

Application to carbon fiber started in this Year. In this paper, a spinning and calcination process are explained. Fiber was obtained by wet spinning of the PAN solution. Ten solvents were tested and the results proved that dimethyl sulfoxide (DMSO) was the best solvent. Glycerine was used as a coagulating bath. The thin fiber (10 to 50 denier) was produced under the conditions of about 20wt% concentration at about 110degC. Heat-treat temperature was about 270 to 275degC. The viscosity-tacticity relationship and T{sub sol} vs. inverse tacticity were shown in the paper. (S.Y.)

1998-01-01

36

Ultrastructural effect of gamma radiation on grass shrimps (Penaeus monodon Fabricius)  

Energy Technology Data Exchange (ETDEWEB)

The effect of ionizing radiation (2, 5, and 10 KGy of gamma rays) on muscle ultrastructure of grass shrimps (Penaeus monodon Fabricius) tails at ambient or frozen (-18{sup 0}C) temperature was investigated by transmission electron microscopy (TEM). No significant change was found in muscle ultrastructure of shrimp meat irradiated at doses of 2 or 5 KGy and then stored at 4{sup 0}C for 0 and 8 days. However, in shrimps which were irradiated at ambient temperature at a dose of 10 KGy, the margin of A-band of the myofibrils in longitudinal sections exhibited an irregular zig-zag pattern. In cross section some myosin filaments in the A-band regions were missing. A possible interpretation of these results would be that 10 KGy gamma irradiation dose at ambient temperature depolymerized myosin in the A-band from the tail of thick filament. Actin damage was also observed in some cross sections. Irradiation damage of sarcoplasmic membranes appeared in ...

1990-01-01

37

Ultrastructural effect of gamma radiation on grass shrimps (Penaeus monodon Fabricius)  

International Nuclear Information System (INIS)

The effect of ionizing radiation (2, 5, and 10 KGy of gamma rays) on muscle ultrastructure of grass shrimps (Penaeus monodon Fabricius) tails at ambient or frozen (-18"0C) temperature was investigated by transmission electron microscopy (TEM). No significant change was found in muscle ultrastructure of shrimp meat irradiated at doses of 2 or 5 KGy and then stored at 4"0C for 0 and 8 days. However, in shrimps which were irradiated at ambient temperature at a dose of 10 KGy, the margin of A-band of the myofibrils in longitudinal sections exhibited an irregular zig-zag pattern. In cross section some myosin filaments in the A-band regions were missing. A possible interpretation of these results would be that 10 KGy gamma irradiation dose at ambient temperature depolymerized myosin in the A-band from the tail of thick filament. Actin damage was also observed in some cross sections. Irradiation damage of sarcoplasmic membranes appeared in the ...

38

Temporal development of GABA agonist induced alterations in ultrastructure and GABA receptor expression in cultured cerebellar granule cells  

DEFF Research Database (Denmark)

The temporal development of the effect of THIP (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol) on the ultrastructure composition and GABA receptor expression in cerebellar granule cells was investigated by quantitative electron microscopy (morphometric analysis) and GABA binding assays. It was found that the cytoplasmic density of smooth endoplasmic reticulum was decreased, while the cytoplasmic density of rough endoplasmic reticulum, Golgi apparatus, vesicles and coated vesicles was greatly enhanced after exposure of the cells to THIP (150 microM) for only 1 hr. In cerebellar granule cells exposed to THIP (150 microM) for 3 hr low affinity GABA receptors were induced. These findings show that the effect of THIP on the ultrastructure composition and GABA receptor expression in cultured cerebellar granule cells may be interrelated and moreover it is likely that the turn-over of GABA receptors is extremely fast.

1987-01-01

39

The advanced manufacturing science and technology program. FY 95 Annual Report  

Energy Technology Data Exchange (ETDEWEB)

This is the Fiscal Year 1995 Annual Report for the Advanced Manufacturing Science and Technology (AMST) sector of Los Alamos Tactical Goal 6, Industrial Partnering. During this past fiscal year, the AMST project leader formed a committee whose members represented the divisions and program offices with a manufacturing interest to examine the Laboratory`s expertise and needs in manufacturing. From a list of about two hundred interest areas, the committee selected nineteen of the most pressing needs for weapon manufacturing. Based upon Los Alamos mission requirements and the needs of the weapon manufacturing (Advanced Design and Production Technologies (ADaPT)) program plan and the other tactical goals, the committee selected four of the nineteen areas for strategic planning and possible industrial partnering. The areas selected were Casting Technology, Constitutive Modeling, Non-Destructive Testing and Evaluation, and Polymer Aging and Lifetime ...

1996-03-01

40

Programmed cell death during pigment gland formation in Gossypium hirsutum leaves  

British Library Electronic Table of Contents (United Kingdom)

Abstract Ultrastructural studies have shown that the formation of pigment glands in Gossypium hirsutum L. leaves is a lysigenous process, originating from a cluster of cells in the ground meristem. Various techniques were used here to investigate whether programmed cell death (PCD) plays a critical role in this developmental process. Nuclei of internal cells in the pigment gland-forming tissue were TUNEL-positive and DAPI-negative, suggesting that DNA cleavage is an early event and complete DNA degradation is a late event. Smeared bands and a lack of laddering after gel electrophoresis indicate that DNA cleavage is random. Ultrastructurally, secretory cells in the pigment glands become distorted, nuclei are densely stained, and chromosomes become condensed until completely degraded at late...

2010-01-01

41

Nickel induced structural and functional alterations in mouse Leydig cells in vitro  

British Library Electronic Table of Contents (United Kingdom)

The present study was aimed at investigating effects of nickel (NiCl2) on secretion of testosterone (T), cell viability, ultrastructure and apoptosis in mouse Leydig cells. Testosterone release was measured after 48h of culture with 15.67, 31.25, 62.5, 125, 250, 500 and 1000mmol/L NiCl2 or without NiCl2 using radioimmunoassay. Cell viability was assessed by a MTT (metabolic activity assay). Quantification of apoptotic cells was performed using TUNEL assay and the ultrastructural changes were analyzed using transmission electron microscopy. The viability was decreased after addition of >=250mmol/L NiCl2. A concentration-dependent depression of T production was observed. The percentage of apoptotic cells was significantly increased only after addition of 125, 250 and 1000mmol/L NiCl2. After ...

2011-01-01

42

Needle aspiration biopsy in the diagnosis of lytic bone lesions in histiocytosis X, Ewing's sarcoma and neuroblastoma  

International Nuclear Information System (INIS)

Cytologic smears obtained by needle aspiration biopsy of lytic bone lesions in 15 patients with histiocytosis X, Ewing's sarcoma and neuroblastoma were reviewed. After conventional staining, histiocytosis X could be diagnosed and differentiated from small cell tumours such as Ewing's sarcoma and neuroblastoma. The need for sampling material for cytochemical and ultrastructural analysis of these small cell tumours by needle aspiration is emphasized. (Auth.).

43

Morphological, Histochemical, Immunohistochemical, and Ultrastructural Characterization of Tumors and Dysplastic and Non-Neoplastic Lesions Arising in BK Virus/tat Transgenic Mice  

UK PubMed Central (United Kingdom)

To study the role in AIDS pathogenesis of the human immunodeficiency virus type 1 (HIV-1) Tat protein, a transactivator of viral and cellular genes, we generated transgenic mice with a recombinant DNA...Full Text Available

1999-04-01

46

The underdog should always fire the first salvo against Brazil  

British Library Electronic Table of Contents (United Kingdom)

A popular myth in football (soccer) that it is unwise tactically to score early against Brazil is busted using data from 1993 to 2010. This result provides further evidence about the choice of timing of effort exertion by an underdog in a finite-length industry contest against a more favoured opponent.

2012-01-01

48

Accepting the Challenge Examining Infantry and Military Police Employment of Competencies on the Twenty-First Century Battlefield.  

Science.gov (United States)

Mission, threat and capabilities adaptations in the twenty-first century continue to change the tasks assigned to U.S. Army Infantry units. Traditional infantry tactical training does not prepare U.S. infantry forces for many of the tasks required in cont...

2003-01-01

49

A Real-Time US Army Tactical Telephone Network ...  

Science.gov (United States)

... To CA 2 TOM 2 L= DTO 2 4 9"ylem 2 a Systsm2OTO 3 Figure 25: Node I C-5 Internal Connectivity C5 DTO 2 GM I sy~stm I 1 RC-IOS L3 To CA ...

1993-09-01

50

Morphological and ultrastructural analysis of Turritopsis nutricula during life cycle reversal.  

Science.gov (United States)

The hydrozoa life cycle is characterized, in normal conditions, by the alternation of a post-larval benthic polyp and an adult pelagic medusa; however, some species of Hydrozoa react to environmental stress by reverting their life cycle: i.e. an adult medusa goes back to the juvenile stage of polyp. This very uncommon life cycle could be considered as some sort of inverted metamorphosis. A morphological study of different stages during the reverted life cycle of Turritopsis nutricula led to the characterization of four different stages: healthy medusa, unhealthy medusa, four-leaf clover and cyst. The ultrastructural study of the cellular modifications (during the life cycle reversion of T. nutricula) showed the presence of both degenerative and apoptotic processes. Degeneration was prevalent during the unhealthy medusa and four-leaf clover stages, while the apoptotic rate was higher during the healthy medusa and cyst stages. The significant presence of degenerative ...

2003-06-01

51

Biochemical and ultrastructural processing of ["1"2"5I]epidermal growth factor in rat epidermis and hair follicles: accumulation of nuclear label  

International Nuclear Information System (INIS)

Although the intracellular ultrastructural processing of epidermal growth factor (EGF) and its receptor have been described in cell culture systems, very few studies have examined this phenomenon in intact tissues. We have examined the ultrastructural and biochemical handling of ["1"2"5I]EGF in the epidermis and hair follicle bulb of intact, viable, 3- to 5-day-old rat skin the EGF receptor distribution of which has already been documented and in which EGF has been shown to be biologically active. After incubation of explants with 10 nM ["1"2"5I]EGF for 2.5 h at 25 degrees or 37 degrees C, radiolabel was detected over the basal cells of the epidermis and hair follicle outer root sheath, confirming previous light microscope observations. More specifically, silver grains were observed near coated and uncoated plasma membrane and coated membrane invaginations, Golgi apparatus, lysosomal structures, and nuclei. Sodium azide inhibited ...

1987-01-01

52

Biochemical and ultrastructural processing of (/sup 125/I)epidermal growth factor in rat epidermis and hair follicles: accumulation of nuclear label  

Energy Technology Data Exchange (ETDEWEB)

Although the intracellular ultrastructural processing of epidermal growth factor (EGF) and its receptor have been described in cell culture systems, very few studies have examined this phenomenon in intact tissues. We have examined the ultrastructural and biochemical handling of (/sup 125/I)EGF in the epidermis and hair follicle bulb of intact, viable, 3- to 5-day-old rat skin the EGF receptor distribution of which has already been documented and in which EGF has been shown to be biologically active. After incubation of explants with 10 nM (/sup 125/I)EGF for 2.5 h at 25 degrees or 37 degrees C, radiolabel was detected over the basal cells of the epidermis and hair follicle outer root sheath, confirming previous light microscope observations. More specifically, silver grains were observed near coated and uncoated plasma membrane and coated membrane invaginations, Golgi apparatus, lysosomal structures, and nuclei. Sodium azide inhibited ...

1987-03-01

53

Short Form of the Developmental Behaviour Checklist  

UK PubMed Central (United Kingdom)

A 24-item short form of the 96-item Developmental Behaviour Checklist was developed to provide a brief measure of Total Behaviour Problem Score for research purposes. The short form Developmental...Full Text Available

2007-01-01

54

Adaptation of the low-cost and low-power tactical split Stirling cryogenic cooler for aerospace applications  

Science.gov (United States)

Cryogenic coolers are often used in modern spacecraft in conjunction with sensitive electronics and sensors of military, commercial and scientific instrumentation. The typical space requirements are: power efficiency, low vibration export, proven reliability, ability to survive launch vibration/shock and long-term exposure to space radiation. A long-standing paradigm of exclusively using "space heritage" equipment has become the standard practice for delivering high reliability components. Unfortunately, this conservative "space heritage" practice can result in using outdated, oversized, overweight and overpriced cryogenic coolers and is becoming increasingly unacceptable for space agencies now operating within tough monetary and time constraints. The recent trend in developing mini and micro satellites for relatively inexpensive missions has prompted attempts to adapt leading-edge tactical cryogenic coolers for suitability in the space environment. The primary ...

2011-05-01

57

Ultrastructure of the spermatozoon of the digenean Cricocephalus albus (Kuhl & van Hasselt, 1822) Looss, 1899 (Platyhelminthes, Pronocephaloidea, Pronocephalidae), parasite of ''the hawksbill sea turtle''Eretmochelys imbricata (Linnaeus, 1766) in Senegal  

British Library Electronic Table of Contents (United Kingdom)

The mature spermatozoon of Cricocephalus albus is filiform, tapered at both ends and shows the following features: 2 axonemes of different lengths presenting the 9+''1'' trepaxonematan pattern, 2 bundles of parallel cortical microtubules, a mitochondrion and a nucleus. Nevertheless, the particularity of the spermatozoon of C. albus is its anterior extremity with an apical electron-dense material associated with extramembranar ornamentation, a cytoplasmic dorsolateral expansion and spine-like bodies. To our knowledge, such an anterior extremity of the spermatozoon has not previously been described from a species of the superfamily Pronocephaloidea. Our study provides new data on the mature gamete of C. albus in order to improve our understanding of the pronocephaloidean phylogenetic relatio...

2011-01-01

58

Paralysis due to a glomangioma in a Macaca mulatta. Final report  

Energy Technology Data Exchange (ETDEWEB)

Glomangioma have many synonyms including: glomus tumors, tumors of neuromyoarterial glomi, angioneuromas, angioneuromyomas, neuromyoarterial glomi, painful subcutaneous tubercles, Popoff tumors or subcotaneous glomal tumors. They are common in humans, rare in nonhuman primates and to the best of our knowledge, have only been reported in irradiated rhesus. The neoplasms originate in arterial-venous shunts known as neuromyoarterial glomi which are commonly found beneath fingernails and fingertips, but have been reported in many locations both superficial and deep. The neoplasm can be confused with hemangiopericytomas, hemangiomas, paragangliomas, and leiomyomas, and must be definitely diagnosed ultrastructurally. A glomangioma at the 6-7 thoracic intervertebral space caused compression of the spinal cord with posterior paralysis in an irradiated 20-year-old female rhesus monkey (Macaca mulatta).

1984-01-01

59

Extracellular matrix of plant callus tissue visualized by ESEM and SEM  

British Library Electronic Table of Contents (United Kingdom)

Actinidia deliciosa endosperm-derived callus culture is stable over a long period of culture. This system was used to investigate the ultrastructure of extracellular matrix occurring in morphogenic tissue. Specimens were prepared by different biological techniques (chemical fixation, liquid nitrogen fixation, glycerol substitution, critical-point drying, lyophilization) and observed by scanning electron microscopy (SEM). Fresh and wet samples were analyzed with the use of environmental scanning electron microscopy (ESEM). Extracellular matrix was observed on the surface of cell clusters as a membranous layer or reticulated network, shrunken or wrinkled, depending on the procedure. Generally, shrunken membranous layers with a globular appearance and fibrils were noted after critical-point d...

2010-01-01

60

Establishment of functional primary cultures of heart cells from the clam Ruditapes decussatus  

British Library Electronic Table of Contents (United Kingdom)

Heart cells from the clam Ruditapes decussatus were routinely cultured with a high level of reproducibility in sea water based medium. Three cell types attached to the plastic after 2?days and could be maintained in vitro for at least 1?month: epithelial-like cells, round cells and fibroblastic cells. Fibroblastic cells were identified as functional cardiomyocytes due to their spontaneous beating, their ultrastructural characteristics and their reactivity with antibodies against sarcomeric ?-actinin, sarcomeric tropomyosin, myosin and troponin T-C. Patch clamp measurements allowed the identification of ionic currents characteristic of cardiomyocytes: a delayed potassium current (I K?slow) strongly suppressed (95%) by tetraethylammonium (1?mM), a fast inactivating potassium current (I K?fas...

2011-01-01

61

Efficient elimination of sweetpotato little leaf phytoplasma from sweetpotato by cryotherapy of shoot tips  

British Library Electronic Table of Contents (United Kingdom)

Shoot tips with 3-4 leaf primordia were excised from in vitro-grown sweetpotato plants (Ipomoea batatas) infected with little leaf phytoplasma (Candidatus Phytoplasma aurantifolia) and subjected to cryotherapy. All plants regenerated from the cryo-treated shoot tips were free of phytoplasma, whereas shoot tip culture or dehydration of shoot tips without subsequent cryotherapy resulted in phytoplasma-free plants at a frequency of only 7-10%. Histological and ultrastructural studies with light and transmission electron microscopy, respectively, indicated that cryotherapy was lethal to all cells except those in the apical dome of the meristem and the two youngest leaf primordia. These surviving parts of the shoot tip contained vascular tissue and sieve elements, but electron microscopy showed...

2008-01-01

62

Biological and morphological characterization of human neonatal fibroblast cell culture B-HNF-1  

British Library Electronic Table of Contents (United Kingdom)

In the present study, human neonatal fibroblasts were isolated from a two-month-old human male. The purpose of the present investigation was the analysis of the morphology (light and transmission electron microscopy), karyotype and growth characteristics of the human neonatal fibroblast cell culture B-HNF-1. Moreover, STR typing and mitochondrial DNA amplification and sequencing was also performed. Analysis of chromosomes count showed that B-HNF-1 cell culture is diploid and has normal male karyotype 46, XY, which was stable during cultivation. The transmission electron microscopy demonstrated the ultra-structure of the B-HNF-1 cells; they have typical morphological features of proteosynthesis-active cells. Large number of fibroblasts bearing different shapes and surface characteristics ad...

2010-01-01

63

The tactical use of constraints and structure in diagnostic problem solving  

British Library Electronic Table of Contents (United Kingdom)

This paper presents a prescriptive account of diagnostic problem solving, or diagnosis, in quality and process control. This paper identifies a general strategy, named branch-and-prune, whose manifestations can be found in disciplines such as medical diagnosis, troubleshooting of devices, and model-based diagnosis in artificial intelligence. The work aims to offer a clear conceptualization of this strategy, based on the notions of structures for the search space, and constraints to the cause's nature.The idea is to treat the search space of candidate explanations as a tree structure, in which general and high-level causal directions are branched into more specific and detailed explanations. Constraints eliminate all but a few branches (pruning), which are explored in more detail. We enumer...

2011-01-01

64

Projective goals - concepts and pragmatic aspects based on the terminology and methodology of safety science  

International Nuclear Information System (INIS)

Protective goals set the line of orientation of tasks and activities in the field of accident prevention. They have to be based on safety-science methods in order to develop from the conceptual idea to the practically feasible solution, while using the scientific methods to take into account the facts and the capabilities of a situation and, proceeding from them, finding an efficient and rational, optimal pragmatic approach by way of various strategies or tactics. In this process, the activities of defining, informing, thinking and developing need the proper terminology. Safety is absence of danger, protection is limitation of danger and prevention of damage. So it is protection what is needed with danger being given, and risks have to be minimized. Riskology is a novel method of safety science, combining risk analysis and risk control into a systematic concept which is practice-oriented. Applying this to the field of nuclear engineering, the hitherto achieved ...

65

A new heuristic method for distribution networks considering service level constraint and coverage radius  

British Library Electronic Table of Contents (United Kingdom)

This paper presents a new mathematical model for designing distribution networks in a supply chain system considering service level constraint optimizing strategic decisions (location), tactical decisions (inventory), and assigning decisions. In real-world cases, demand, traveling time or any parameters in classical models may change over the period of time. So, considering uncertainty yields more flexibility for the results and the proposed model. In our study, environmental uncertainty is described by discrete scenarios. In this model, we have service level constraint in order to prevent inventory lost in distribution centers (DCs). Also, we assume that customer's demand is stochastic with Poisson distribution function and DCs have coverage radius constraints thus any DC cannot service a...

2009-01-01

66

Induction of biotransformation in the liver of Eel (Anguilla anguilla L. ) by sublethal exposure to dinitro-o-cresol: An ultrastructural and biochemical study  

Energy Technology Data Exchange (ETDEWEB)

Structural and functional alterations in hepatocytes of the European eel, Anguilla anguilla, following a 4-week-exposure to 5, 50, and 250 micrograms/liter dinitro-o-cresol (DNOC) were investigated by means of electron microscopy and biochemistry and compared to liver pathology in eels exposed to the chemical spill into the Rhine river at Basle in November 1986. Whereas phenological parameters (growth, condition factor) are unaffected, ultrastructural and biochemical alterations are detectable at greater than or equal to 50 and 5 micrograms/liter DNOC, respectively. Structural modifications include: rounding-up of the nuclei; fractionation and reduction of the rough endoplasmic reticulum; proliferation of the smooth endoplasmic reticulum (SER), mitochondria, peroxisomes, and lysosomes; bundles of rod-shaped SER profiles; annulate lamellae; membrane whorls within mitochondria; crystallization of the peroxisomal matrix and glycogen bodies; glycogen depletion and ...

1991-04-01

67

Sexual behaviour of men that consulted in medical outpatient clinics in Western Switzerland from 2005-2006: risk levels unknown to doctors?  

UK PubMed Central (United Kingdom)

BackgroundTo determine male outpatient attenders' sexual behaviours, expectations and experience of talking about their sexuality and sexual health needs with a doctor.MethodsA...Full Text Available

68

Self-management of fatigue in rheumatoid arthritis: a randomised controlled trial of group cognitive-behavioural therapy  

UK PubMed Central (United Kingdom)

ObjectivesTo investigate the effect of group cognitive behavioural therapy (CBT) for fatigue self-management, compared with groups receiving fatigue information alone, on fatigue...Full Text Available

69

Key Beliefs for Targeted Interventions to Increase Physical Activity in Children: Analyzing Data from an Extended Version of the Theory of Planned Behaviour  

UK PubMed Central (United Kingdom)

Given the high prevalence of overweight and low levels of physical activity among children, a better understanding of physical activity behaviour is an important step in intervention planning. This...Full Text Available

2010-01-01

70

Flexible responses to visual and olfactory stimuli by foraging Manduca sexta: larval nutrition affects adult behaviour  

UK PubMed Central (United Kingdom)

Here, we show that the consequences of deficient micronutrient (β-carotene) intake during larval stages of Manduca sexta are carried across metamorphosis, affecting adult behaviour....Full Text Available

2009-08-07

71

Brain transcriptomic analysis in paper wasps identifies genes associated with behaviour across social insect lineages  

UK PubMed Central (United Kingdom)

Comparative sociogenomics has the potential to provide important insights into how social behaviour evolved. We examined brain gene expression profiles of the primitively eusocial wasp Polistes...Full Text Available

2010-07-22

72

Behavioural assessment of pediatric pain  

UK PubMed Central (United Kingdom)

Behavioural assessment methods have been used to signal the need for intervention and to evaluate treatment effectiveness. Direct observation and rating scales have been used to assess pain and distress...Full Text Available

2009-01-01

73

Improved control of fuel crushing in coal-fired power stations  

Energy Technology Data Exchange (ETDEWEB)

With the frequent load changes to which a hard coal power station is subjected in the middle and peak load range, great demands are linked with the transient behaviour of the steam generator. Due to the serial connection of the crusher and boiler, the strongly delaying transient behaviour of the crusher compounds entirely with the transient behaviour of the steam generator. Therefore, a suggestion is to be made here as to the improvement of the dynamics of the crusher.

1988-01-01

74

Chaotic behaviour in higher-order gravity theories  

Energy Technology Data Exchange (ETDEWEB)

We show that the chaotic dynamical behaviour displayed by diagonal Bianchi type IX metrics in general relativity does not occur on approach to the singularity in higher-order lagrangian theories of gravity. However, chaotic behaviour does occur in the more general non-diagonal type IX models in these theories. An interpretation of these results in terms of the hamiltonian potential picture of the type IX evolution is given. (orig.).

1989-11-30

75

Chaotic behaviour in higher-order gravity theories  

International Nuclear Information System (INIS)

We show that the chaotic dynamical behaviour displayed by diagonal Bianchi type IX metrics in general relativity does not occur on approach to the singularity in higher-order lagrangian theories of gravity. However, chaotic behaviour does occur in the more general non-diagonal type IX models in these theories. An interpretation of these results in terms of the hamiltonian potential picture of the type IX evolution is given. (orig.).

76

A laboratory study on the thermomechanical behaviour of clayey soils  

Energy Technology Data Exchange (ETDEWEB)

The thermomechanical behaviour of clayey soils was examined in a laboratory study because of their importance in some engineering applications such as hydrocarbon extraction from oil-bearing sands and radioactive waste disposal. The slightest temperature variations have been known to have an impact on the mechanical behaviour of clayey soils. In this study, tests were conducted on reconstituted and natural clayey soils using triaxial cells modified to control temperatures. Changes of temperature and stress state were not applied simultaneously. Instead, the tests were divided into two separate sections aimed at studying the thermal and mechanical behaviour of clays. The thermal behaviour tests examined the deformations induced by drainage temperature changes as well as pore-pressure generation and consolidation phenomena. The mechanical behaviour tests, focused on the influence of ...

2000-08-04

77

Morphological and molecular redescription of the myxozoan Unicapsula pflugfelderi from two teleost hosts in the Mediterranean. A review of the genus Unicapsula Davis 1924  

British Library Electronic Table of Contents (United Kingdom)

Abstract Elongate plasmodia with myxosporean spores belonging to the genus Unicapsula, Davis, 1924 were found in the skeletal muscle of the striped seabream, Lithognathus mormyrus (L.), a candidate for the mediterranean aquaculture. The only species of Unicapsula described from the Mediterranean is Unicapsula pflugfelderi Schubert et al. 1975, which occurs in the picarel, Spicara smaris (L.). For morphological and molecular comparison of U. pflugfelderi from S. smaris with Unicapsula sp. from L. mormyrus measurements of plasmodia and spores, ultrastructural details and 18S and 28S rDNA sequences were analysed. Whereas plasmodia were 2-3 times larger in S. smaris than in L. mormyrus (length 2.47-0.81 mm; width 0.22-0.09 mm; P = 0.000), spore morphology showed minor differences and both 18S ...

2009-01-01

78

Influence of substrates on nitrogen removal performance and microbiology of anaerobic ammonium oxidation by operating two UASB reactors fed with different substrate levels.  

Science.gov (United States)

Both ammonium and nitrite act as substrates as well as potential inhibitors of anoxic ammonium-oxidizing (Anammox) bacteria. To satisfy demand of substrates for Anammox bacteria and to prevent substrate inhibition simultaneously; two strategies, namely high or low substrate concentration, were carefully compared in the operation of two Anammox upflow anaerobic sludge blanket (UASB) reactors fed with different substrate concentrations. The reactor working at relatively low influent substrate concentration (NO(2)(-)-N, 240 mg-NL(-1)) was shown to avoid the inhibition caused by nitrite and free ammonia. Using the strategy of low substrate concentration, a record super high volumetric nitrogen removal rate of 45.24 kg-Nm(-3) day(-1) was noted after the operation of 230 days. To our knowledge, such a high value has not been reported previously. The evidence from transmission electron microscopy (TEM) showed that the morphology and ultrastructure of the Anammox cells in ...

2010-04-13

79

Erratum to: Inhibition of triclabendazole metabolism in vitro by ketoconazole increases disruption to the tegument of a triclabendazole-resistant isolate of Fasciola hepatica  

British Library Electronic Table of Contents (United Kingdom)

A study has been carried out to investigate whether the action of triclabendazole (TCBZ) against Fasciola hepatica is altered by inhibition of drug metabolism. The cytochrome P450 (CYP 450) enzyme pathway was inhibited using ketoconazole (KTZ) to see whether a TCBZ-resistant isolate could be made more sensitive to TCBZ action. The Oberon TCBZ-resistant and Cullompton TCBZ-susceptible isolates were used for these experiments. The CYP 450 system was inhibited by a 2-h pre-incubation in ketoconazole (40??M), then incubated for a further 22?h in NCTC medium containing either KTZ, KTZ?+?nicotinamide adenine dinucleotide phosphate (NADPH) (1?nM), KTZ?+?NADPH?+?TCBZ (15??g/ml), or KTZ?+?NADPH?+?triclabendazole sulphoxide (TCBZ.SO; 15??g/ml). Changes to fluke ultrastructure following drug treatmen...

2011-01-01

80

The influence of martensitic transformation on mechanical properties of cast high alloyed CrMnNi-steel under various strain rates and temperatures  

International Nuclear Information System (INIS)

Metastable austenitic steels show excellent mechanical properties, such as high strength combined with excellent ductility and toughness due to martensitic transformation under mechanical loading (transformation induced plasticity effect). A good energy consumption, and, in the case of high-alloyed metastable austenitic steels, a high corrosion resistance, increase the potential of these materials for diverse applications, also in regard of safety requirements. Up to now, numerous wrought alloys were investigated concerning mechanical behaviour, TRIP-effect, martensitic transformation behaviour and modelling of transformation kinetics or stress-strain behaviour. New high alloyed cast CrMnNi-steels, developed at Technical University Bergakademie Freiberg, provide the chance to reduce processing steps, production time and costs. In order to understand the influence of temperature on the martensitic phase transformation ...

2010-07-01

81

Transient behaviour of solar heated radiation receivers for small gas turbine power plants  

Energy Technology Data Exchange (ETDEWEB)

Solar heating of gas turbine plants steps back more and more into the focus of current research. The mainly instationary operation of solar turbine power plants can only be predicted with sufficient accuracy if the transient behaviour of the receiver for the solar radiation is known. Therefore the transient behaviour of cavity receivers of different design is investigated. The mathematical model used for the simulation of the heat transfer and energy storage processes is illustrated. Computed results for receivers with various inner lining are compared and evaluated concerning their use in practice.

1987-03-01

82

System reliability of timber structures with ductile behaviour  

British Library Electronic Table of Contents (United Kingdom)

The present paper considers the evaluation of timber structures with the focus on robustness due to connection ductility. The robustness analysis is based on the structural reliability framework applied to a simplified mechanical system. The structural timber system is depicted as a parallel system. An evaluation method of the ductile behaviour is introduced. For different ductile behaviours, the system reliability is estimated based on Monte Carlo simulation. A correlation between the strength of the structural elements is introduced. The results indicate that the reliability of a structural timber system can be significantly increased due to the ductile behavior.

2011-01-01

83

Proceedings of the third international conference on containment design and operation. v.1  

International Nuclear Information System (INIS)

The second international conference on containment design and operation included sessions on the following topics: performance and regulatory requirements; radionuclide behaviour; severe accident design and analysis; operation, maintenance, leaking and aging of containment systems; thermal hydraulic behaviour of containment systems; hydrogen mixing and mitigation; design methods and concepts; code validation; structural analysis and response tests; passive safety systems; aerosol behaviour; containment reliability, integrity, and risk assessment; hydrogen deflagration and detonation. Due prominence was given to CANDU and other PHWR reactors. The individual papers have been abstracted separately.

1994-10-19

84

Dynamic stability and vibration monitoring for No. 9 mine, M-1 dump  

Energy Technology Data Exchange (ETDEWEB)

This study examines the effects of blasting on waste dumps at open pit mining operations. Of specific concern were mining operations at the base of a five hundred foot high waste dump such as the operation at the South Pit of the Smoky-River Coal Ltd. property near Grande Cache, Alberta. An assessment of waste dump stability including factors such as quasi-static deformation behaviour, historical dump deformation behaviours and potential blasting effects was undertaken. It is concluded that safe blasting may be carried out in proximity to waste dumps, but monitoring of dump behaviour is recommended to ensure operational safety. 22 refs., 4 apps.

1988-11-01

85

Application of relationship marketing and management: a large contractor case study  

British Library Electronic Table of Contents (United Kingdom)

Marketing-led enterprise change management initiated by a major UK contractor is explored in this paper as a contrast to procurement-led changes to projects driven by clients. Procurement-led initiatives try to induce changes to behaviour through market governance. Relationship marketing and management proactively change organizational behaviour, the enterprise taking responsibility for its own destiny. Investment and resource allocation, and organizational behaviour have posed constraints, particularly concerning service continuity in construction. Overcoming these constraints offers opportunities for delivering service improvements and adding value for clients and yielding further increases in repeat business and increasing profitability. Relationship marketing is the conceptual starting...

2009-01-01

86

Use of fuel cells to meet military requirements for mobile power  

International Nuclear Information System (INIS)

'Full text:' The use of fuel cell technology in military applications will depend on safe, high energy density systems being developed. An important part of using this technology is also the development of alternative hydrogen producing fuels with high energy densities and are easy to transport. Fuel cells are now a very large R and D effort for several military applications around the world. The major reason is because of the high power demands needed requires electrical energy sources that far exceed the capabilities of batteries currently being fielded for portable applications. Fuel cells are regarded as highly efficient, tactical energy converters that can be adapted for wide range of power requirements. They are potentially the lowest weight power source when coupled with batteries or capacitors to form hybrid systems. Generally electrical power is needed to support a number of applications from ultra-high power for electrical pulses (radios, sensors) to ...

2004-09-25

87

Truck tactics: dispatch from Vancouver  

Energy Technology Data Exchange (ETDEWEB)

Any mine that uses haultrucks has a dispatching system of some sort, even if it is only a very basic and simple arrangement. The larger, more complex operations have found that, if properly applied, automated computerised dispatching improves the productivity of the equipment as well as improving overall control and reporting. However, not every mine can justify going this far; in these cases a computerised monitoring and reporting system with manual dispatching can still give considerable benefits. Wenco International Mining Systems of Vancouver supplies its computerised system to three different specification levels to suit most open pit mining operations. The article describes the 3 PMCSs (Production Monitoring and Control System) available: PMCS 1000, for monitoring and reporting only; PMCS 2000, for dispatching to maximise production; and PMCS 3000, for dispatching with optimised product quality and production. The major components of the PMCS are: mobile data terminals fitted to ...

1991-11-01

88

Planning logistics operations in the oil industry  

International Nuclear Information System (INIS)

In this paper we apply stochastic programming modelling and solution techniques to planning problems for a consortium of oil companies. A multiperiod supply, transformation and distribution scheduling problem - the Depot and Refinery Optimization Problem (DROP) - is formulated for strategic or tactical level planning of the consortium's activities. This deterministic model is used as a basis for implementing a stochastic programming formulation with uncertainty in the product demands and spot supply costs (DROPS), whose solution process utilizes the deterministic equivalent linear programming problem. We employ our STOCHGEN general purpose stochastic problem generator to 'recreate' the decision (scenario) tree for the unfolding future as this deterministic equivalent. To project random demands for oil products at different spatial locations into the future and to generate random fluctuations in their future prices/costs a stochastic input data simulator is ...

89

A Plan to Diffuse Instructional Materials for Use by Transportation Educators.  

Science.gov (United States)

A plan to diffuse instructional modules for the preparation of transportation professionals is presented, based on research and demonstration projects sponsored by the Urban Mass Transportation Administration (UMTA). The diffusion/adoption plan involves: developing instructional modules; disseminating the modules to professors teaching transportation courses at the college level; promoting the use and adoption of the modules; and evaluating and revising the plan. Transportation educators teach in a variety of disciplines (e.g., engineering, public administration, urban planning, and technology). Eight design and evaluation criteria for the instructional modules are listed, along with the procedures used by West Virginia University in developing the five instructional modules. The diffusion strategy involves repackaging UMTA research findings, change agents, and the use of information channels (e.g, television/radio, periodicals, direct mail). Adoption tactics ...

1986-01-01

92

Tachyons and theory of quasi-catastrophes  

International Nuclear Information System (INIS)

The author discusses the formulation and application of the theory of quasi-catastrophes for the behaviour and properties of tachyons. This approach assists in the interpretation of experiments where tachyons may be involved. (W.D.L.).

93

TAIL FLIP AND ESCAPE RESPONSE OF TETHYSBAENA ARGENTARII (MALACOSTRACA: THERMOSBAENACEA)  

Science.gov (United States)

... A. Ferrero. 2000. Escape behaviour in the stomatopod crustacean Squilla mantis, and the evolution of the caridoid escape reaction. ... ...

94

Study on fracture behaviour of Al?15%Mg2Si metal matrix composite with and without beryllium additions  

British Library Electronic Table of Contents (United Kingdom)

In this study, the influence of Beryllium (Be) content on the fracture behaviour of Al?15%Mg2Si composite was investigated. The results showed an increase in mechanical properties with increasing of Be content. The stress?strain curves of samples showed a same category of serrations reflecting non-uniform deformation. Scanning electron microscopy was employed to examine the crack nucleation and fracture model. The results indicate that Al?15%Mg2Si composite shows different behaviours of crack initiation and fracture for samples with and without Be. Differences observed in the fracture behaviour were attributed to microstructural changes as well as morphological aspects of primary Mg2Si particles.

2011-01-01

95

Securing co-operation from persons supplying statistical data  

UK PubMed Central (United Kingdom)

Securing the co-operation of persons supplying information required for medical statistics is essentially a problem in human relations, and an understanding of the motivations, attitudes, and behaviour...Full Text Available

1954-01-01

96

New symmetry of intended curved reaches  

UK PubMed Central (United Kingdom)

BackgroundMovement regularities are inherently present in automated goal-directed motions of the primate's arm system. They can provide important signatures of intentional behaviours...Full Text Available

97

Influence of anthropogenic stress on fitness and behaviour of a key-species of estuarine ecosystems, the ragworm Nereis diversicolor  

British Library Electronic Table of Contents (United Kingdom)

Fitness, (biometric measurements, reproduction) and behaviour that are ecologically relevant biomarkers in assessing the quality of estuarine sediments were studied by comparing the responses of the polychaete worm Nereis diversicolor - a key species in estuaries - along a pollution gradient. Intersite differences were shown for all the measured parameters: size-weight relationships, energy reserves as glycogen and lipids, sexual maturation patterns, total number of oocytes per female, total and relative fecundity, burrowing behaviour. The physiological and behavioural status of N. diversicolor was consistently disturbed in the larger, most contaminated estuaries (Loire and Seine, Fr.) compared to reference sites (Bay of Bourgneuf, Goyen estuary, Fr.). Many classes of potentially toxic che...

2010-01-01

98

High temperature deformation behaviour of Ti-10V Alloy and associated activation energy  

International Nuclear Information System (INIS)

High temperature deformation behaviour of an experimental Beta-titanium alloy Ti-10V has been studied in the temperature range 800 to 945 degree C by using the method of crosshead speed cycling. Although subgrain formation was observed but the alloy did not exhibit superplastic behaviour in the entire temperature range studied. A very large initial grain size and elongation of grains during the deformation are considered the main factors responsible for absence of superplastic behaviour. The activation energy values for regions II and III of the ln sigma vs. ln small epsilon plots are close to the lower of the two activation energy values proposed together to describe self diffusion in beta-phase suggesting that the rate controlling mechanism is that for lattice diffusion rather then grain boundary diffusion. (author)

2004-06-01

99

Effective Parameters on the Stress-Strain Curve of Nylon 66/Clay Nanocomposite Using FEM  

British Library Electronic Table of Contents (United Kingdom)

Abstract:- In recent years, the study of polymer/clay nanocomposites has attracted major research and commercial interests due to their superior mechanical and thermal properties to those of the neat polymers. Numerical modelling is an advantageous approach to understand the material behaviour. In this work a symmetric two dimensional finite element model is developed to simulate the fully exfoliated Polymer/Clay nanocomposite behaviour and evaluate its- before stress stress-strain curve. The Nylon 66/Clay in this study has a nonlinear elastic behaviour. The influence of volume fraction and aspect ratio of clay platelet (defined as the ratio of the particle length to the particle thickness) on the tensile behaviour of exfoliated Nylon 66/clay nanocomposite is investigated with the aid of n...

2011-01-01

100
101

Chronic maternal stress affects growth, behaviour and hypothalamo?pituitary?adrenal function in juvenile offspring  

British Library Electronic Table of Contents (United Kingdom)

Maternal stress during pregnancy, particularly that combined with low socioeconomic status (SES), has been linked to an increased risk for impaired behavioural and emotional development and affective disorders in children. In animal models, acute periods of prenatal stress have profound effects on hypothalamo-pituitary-adrenal (HPA) function and behaviour. However, few studies have determined the impact of chronic exposure to stress in animal models. The objective of this study was to determine the effects of chronic maternal stress (CMS) during the 2nd half of pregnancy and nursing on growth, locomotor behaviour and HPA axis function in juvenile guinea pig offspring. Pregnant guinea pigs were exposed to a random combination of variable stressors every other day over the 2nd half of gestat...

2008-01-01

103

The thermodynamic behaviour of spray cooler in the climatic conditions of underground mines. Das thermodynamische Verhalten von Spruehkuehlern unter grubenklimatischen Betriebsbedingungen  

Energy Technology Data Exchange (ETDEWEB)

In this work, the thermodynamic behaviour of single-stage horizontal spray coolers with one or more spray levels is experimentally examined. Further, a spray cooler calculation model was developed, in order to describe the processes and to make a comparison of the results of calculation and measurement. The state of the mine climate and the cold water are taken as the thermodynamic reference. (orig.).

1988-09-14

104

Relationship between microstructural evolution and low cycle fatigue behaviour at 550/sup 0/C of alloy 800 grade 2  

Energy Technology Data Exchange (ETDEWEB)

In this study, deformation modes and precipitations have been characterized in test pieces made of alloy 800, grade 2 hyper-hardened state and age-conditioned for 3000 h at 550/sup 0/C, used for steam generator tubes of the Super Phenix Reactor, after continuous fatigue and fatigue-relaxation tests in the oligocyclic range. This microstructural study has provided an interpretation of the fatigue behaviour of the material.

1989-01-01

105

Pipe behaviour in bottom ash slurry systems  

Energy Technology Data Exchange (ETDEWEB)

This study presents the results of an 18-year long investigation of pipe deterioration in cyclone slag slurry transport. The goal was to study pipe behaviour in this extremely abrasive service and select an optimum piping material. Comparisons are given for high quality alloy cast steel pipes and pipes alined with cast basalt rings marketed under the name Abresist.

1982-09-01

106

Pipe behaviour in bottom ash slurry systems  

Energy Technology Data Exchange (ETDEWEB)

This study presents the results of an 18-year long investigation of pipe deterioration in cyclone slag slurry transport. The goal was to study pipe behaviour in this extremely abrasive service and select an optimum piping material. Comparisons are given for high quality alloy cast steel pipes and pipes lined with cast basalt rings marketed under the name Abresist. Based on the results, thoughts are offered on the broader meanings of certain findings.

1982-09-01

107

On the effect of misch metal addition on corrosion behaviour of aluminium in inorganic and organic acids  

Energy Technology Data Exchange (ETDEWEB)

The effect of small misch metal additions (0.25 to 1 wt.%) on the corrosion behaviour of aluminium was studied through electrochemical polarization in 0.1 N inorganic and organic acids at room temperature. It has been observed that rare earth addition improves the corrosion resistance of aluminium. (orig.).

1992-10-01

108

Long-term behaviour of heat-resistant steels and high-temperature materials. Langzeitverhalten warmfester Staehle und Hochtemperaturwerkstoffe  

Energy Technology Data Exchange (ETDEWEB)

This book contains 10 lectures with the following subjects: On the effect of thermal pretreatment on the structure and creep behaviour of the alloy 800 H (V. Guttmann, J. Timm); Material properties of heat resistant ferritic and austenitic steels after cold forming (W. Bendick, H. Weber); Investigations for judging the working behaviour of components made of alloy 800 and alloy 617 under creep stress (H.J. Penkalla, F. Schubert); Creep behaviour of gas turbine materials in hot gas (K.H. Kloos et al.); Effect of small cold forming on the creep beahviour of gas turbine blades made of Nimonic 90 (K.H. Keienburg et al.); Investigations on creep fatigue alternating load strength of nickel alloys (G. Raule); Change of structure, creep fatigue behaviour and life of X20 Cr Mo V 12 1 (by G. Eggeler et al.); Investigations on thermal fatigue behaviour (K.H. Mayer et al.); Creep ...

1987-01-01

109

Gauge fixing, infrared divergences and confinement  

Energy Technology Data Exchange (ETDEWEB)

The generating functional in which the residual gauge freedom has been broken is related to the conventional generating functional for QED in arbitrary dimension. Closed expressions which relate ordinary N-point Green functions to N-point Green functions in the different gauges are derived. The leading logarithmic behaviour of the electron propagator in three dimensions is thus obtained. It is argued that one should not ascribe much importance to the infrared behaviour of the fermion propagator in the context of confinement.

1984-09-27

110

Cuckoo Search via Levy Flights  

CERN Document Server

In this paper, we intend to formulate a new metaheuristic algorithm, called Cuckoo Search (CS), for solving optimization problems. This algorithm is based on the obligate brood parasitic behaviour of some cuckoo species in combination with the Levy flight behaviour of some birds and fruit flies. We validate the proposed algorithm against test functions and then compare its performance with those of genetic algorithms and particle swarm optimization. Finally, we discuss the implication of the results and suggestion for further research.

2010-01-01

111

Prediction of fatigue crack growth behaviour of an #alpha#-#beta# titanium alloy in Paris-regime using LCF properties  

International Nuclear Information System (INIS)

A model has been developed in the recent past to predict fatigue crack growth (FCG) behaviour in the Paris-regime of various steels by employing low cycle fatigue (LCF) properties. The model forms its basis on the assumption that the cyclic damage process immediately ahead of a crack-tip, restricted in a small zone termed as process zone, is identical to those experienced in the LCF loading of a smooth specimen. Within the process zone, fatigue damage has been assumed in terms of product of stress and plastic strain which is analogous to the plastic strain energy density of the smooth specimen under fatigue loading. In this paper the model developed by Kujawski and Ellyin has been used to predict the FCG behaviour of an #alpha#-#beta# titanium alloy in the Paris-regime by employing the experimentally obtained LCF properties. The FCG behaviour thus theoretically predicted was compared with the experimentally determined FCG ...

112

Influence of anthropogenic stress on fitness and behaviour of a key-species of estuarine ecosystems, the ragworm Nereis diversicolor  

Energy Technology Data Exchange (ETDEWEB)

Fitness, (biometric measurements, reproduction) and behaviour that are ecologically relevant biomarkers in assessing the quality of estuarine sediments were studied by comparing the responses of the polychaete worm Nereis diversicolor - a key species in estuaries - along a pollution gradient. Intersite differences were shown for all the measured parameters: size-weight relationships, energy reserves as glycogen and lipids, sexual maturation patterns, total number of oocytes per female, total and relative fecundity, burrowing behaviour. The physiological and behavioural status of N. diversicolor was consistently disturbed in the larger, most contaminated estuaries (Loire and Seine, Fr.) compared to reference sites (Bay of Bourgneuf, Goyen estuary, Fr.). Many classes of potentially toxic chemicals present in these estuaries most likely contribute to these impairments but food availability may act as a confounding factor, ...

2010-01-15

113

Cell behaviour on chemically microstructured surfaces  

Energy Technology Data Exchange (ETDEWEB)

Micropatterned surfaces with different chemical topographies were synthesised in order to investigate the influence of surface chemistry and topography on cell behaviour. The microstructured materials were synthesised by photoimmobilising natural Hyaluronan (Hyal) and its sulphated derivative (HyalS), both adequately functionalised with a photorective moiety, on glass substrates. Four different grating patterns (10, 25, 50 and 100 {mu}m) were used to pattern the hyaluronan. The micropatterned samples were analysed by Secondary Ions Mass Spectrometry, Scanning Electron Microscopy (SEM) and Atomic Force Microscopy to investigate the chemistry and the topography of the surfaces. The spectroscopic and microscopic analysis of the microstructured surfaces revealed that the photoimmobilisation process was successful, demonstrating that the photomask patterns were well reproduced on the sample surface. The influence of chemical topographies on the cell ...

2003-03-03

114

A critical review of behavioural treatments for chronic benign pain other than headache.  

Science.gov (United States)

Studies of the effectiveness of operant, relaxation, cognitive, and multimodal behavioural approaches to the treatment of chronic benign pain other than headache were evaluated. In general, the quality of the studies was poor, and most investigations lacked appropriate and adequate control conditions, outcome measures, and/or follow-ups. While outcome reports for all four behavioural treatments have been mainly positive, few data were found which conclusively demonstrate that any of the approaches are effective or that they are the treatment of choice. The data do, however, imply that behavioural approaches may help patients lead more normal and productive lives. Specifically, the literature suggests that: (1) the operant method leads to increased activity levels and decreased pain and drug intake, (2) the relaxation approach results in decreased EMG levels and some pain reductions, (3) the cognitive techniques are ...

1982-11-01

115

The importance of sodium plume behaviour in the natural convection cooling of fast reactors  

International Nuclear Information System (INIS)

This paper relates to a simple approach to the analysis of the behaviour of pool type LMFBR primary circuits in natural convection and to experimental work to support this approach. The primary application is the prediction of plant behaviour in decay heat removal conditions when depending on natural convection effects to cool the core. In formulating a mathematical model of the plant for this application, the main difficulty is the modelling of the large plena between the core and IHX and the IHX and the pump inlet. In a previous paper discussing CDFR behaviour after a reactor scram with total loss of power to the primary pumps, the first author described attempts to model the CDFR hot pool in a way which would be limiting in a pessimistic sense. The shortcomings of these attempts were reviewed and mention was made of an improved method then under development. Essentially, the improved model allowed for migration of hot ...

116

Consumer attitudes and decision-making with regard to genetically engineered food products: A review of the literature and a presentation of models for future research  

DEFF Research Database (Denmark)

Executive summary 1. Few studies have to date explained consumer attitudes and purchase decisions with regard to genetically engineered food products. However, the increased marketing of genetically engineered food products and the considerable concern that consumers seem to express with regard to the technology call for the development of a theoretical basis for research into these issues. 2. The aim of the paper is to present three models which we have developed to explain consumer attitudes, buying behaviour and attitude change with regard to genetically engineered food products. All three models build on established consumer behaviour theory and on existing and comparable research in the field. 3. Consumer attitudes toward genetic engineering in food products are explained in an attitude model that builds on Fishbein's multiattribute attitude model. The model deviates from Fishbein's model in a number of ways: there is an explicit ...

1998-01-01

117

Simplification of Finite Element Models for Structures Having a Beam-Like Behaviour  

Science.gov (United States)

A method for simplifying finite element models of structures having a beam-like global dynamical behaviour is presented. This method is based on the use of a general uniform beam finite element formulation. It takes into account both transverse shear effects and dynamical coupling between bending and torsion due to the fact that mass centres and shear centres do not always coincide. For that purpose, we develop a condensation method for reducing any shell model into an equivalent beam, as well as a technique for automatically identifying the corresponding set of beam parameters. The method is applied to several illustrate examples that demonstrate its ability to simplify finite element models for many kinds of sophisticated structures having a beam-like predominant behaviour.

2000-04-01

118

Microstructure and mechanical behaviour of an elevated temperature Mg-rare earth based alloy  

International Nuclear Information System (INIS)

AM-SC1 is a heat treatable magnesium alloy that has been specifically developed to achieve the elevated temperature strength and creep properties necessary for engine block applications. This paper describes the interrelationship between the microstructure and the mechanical properties of AM-SC1. The compressive and tensile strengths are relatively insensitive to temperature up to and including 450 K and the tensile yield behaviour deviates from a standard Hall-Petch relationship at grain sizes below 200 ?m. The microstructural features contributing to the creep resistance are both inter- and intra-granular in nature and are on length scales from nanometers to micrometers. The creep behaviour at 423 K and 450 K is diffusion controlled, with any contribution from the grain boundaries being negligible.

2009-04-15

119

Investigation of the steady state and transient operating behaviour of a 20 kW pressure electrolyser  

Energy Technology Data Exchange (ETDEWEB)

The present paper describes the investigation of the static and dynamic behaviour of an 20 kW pressure electrolyser. The suitability for a coupled operating regime with a wind power plant has been investigated. At first the static behaviour has been analysed. The share of oxygen in hydrogen gas is lower than 0.5 Vol%. But reaching the temperature limit of 80 deg C leads to a switch off of the electrolyser, accompanied by an increase of the oxygen share in hydrogen gas up to 1.3 Vol%. Therefore, an improvement of the cooling system is necessary. Secondly, the electrolyser was excited by different step signals for load changing and finally, the electrolyser has been controlled by the power output signal of the windmill. The investigation shows that the development of a direct coupled wind-hydrogen system will be only a small step. 3 refs.

1998-07-01

120

Fatigue of magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

Magnesium alloys show a high specific strength and are therefore increasingly used for light-weight constructions in transportation industry.{sup [1,2]} To predict the behaviour of the material under the influence of cyclic loading it is vital to understand the fatigue behaviour of magnesium alloys. Only when understood properly, it is possible to fully apply the potential weight reduction by using magnesium alloys. A very important aspect in fatigue of magnesium alloys is the influence of a corrosive media and elevated temperatures, of which both are relevant in automotive applications. These two factors tend to have deleterious effects on magnesium alloys and therefore also have to be considered in investigations on the fatigue behaviour of magnesium alloys. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

2004-05-01

121

Dielectric behaviour of emeraldine base polymer?ZnO nanocomposite film in the low to medium frequency  

British Library Electronic Table of Contents (United Kingdom)

Emeraldine base (EB) polymer?ZnO nanoparticles composite films has been synthesized by solution casting technique on ITO-coated glass substrate and characterized by XRD, FTIR and TEM for their structure and morphology. Dielectric behaviour of these composite films has been investigated in the very low frequency region to medium frequency region (1?kHz?1?MHz). The dielectric constant of the composite with 30% nanoparticles is almost one-tenth of the pure EB. The dielectric value becomes constant in the frequency region greater than 400?kHz. The change in dielectric behaviour of the composite is explained on the basis of multilayered interface formed between the ZnO nanoparticles and emeraldine chains. Nanoparticles have high energy surface which is responsible for the decrease of free volum...

2011-01-01

122

Are there bubbles in the REITs market? New evidence using regime-switching approach  

British Library Electronic Table of Contents (United Kingdom)

This study looks for the presence of rational speculative bubbles in Real Estate Investment Trusts (REITs) using unit-root, variance ratio, duration dependence and regime switching regression tests. The regime switching method provides weak evidence of speculative bubble behaviour in both the mortgage and hybrid REITs sectors even though traditional econometric bubble tests do not provide evidence of rational speculative bubbles in all REIT markets. Findings suggest that price movement in mortgage and hybrid REITs may be induced by bubble-like behaviour of investors. This behaviour may be traced to the real estate market bubble. Our results provide evidence that the real estate bubble that started in early 2000 was transmitted into securitized real estate markets. A regime switching model ...

2011-01-01

123

An amusing analogy: modelling quantum-type behaviours with wormhole-based time travel  

Energy Technology Data Exchange (ETDEWEB)

When backward time travel through wormholes is taken into account, classical physics loses its determinism and allows simulation of some quantum behaviours. We show how it is possible to simulate a non-local wavefunction reduction-type effect, i.e. we present a mechanical analogy for the collapse of the wavefunction of an entangled state of two removed particles. This situation can be seen as the simplest EPR situation, i.e. the situation where there is just one direction to measure along the spin (or the correlated properties). We present no rigorous results here, just a different point of view about something that is generally thought to be impossible: modelling a quantum indeterministic and non-local behaviour with a mechanical system.

2002-08-01

124

Alloy 800 specifications in compliance with component requirements  

Energy Technology Data Exchange (ETDEWEB)

In view of the importance of the material Alloy 800 in high-temperature reactor plants (HTR), a material data bank was established which is used for statistical evaluation of mechanical and physical material behaviour. Based on investigations on the interconnection between the mechanical properties at high temperatures and the metallurgical parameters, different types of Alloy 800 were specified in compliance with the component requirements. In addition, aspects of corrosion and toughness behaviour were taken into consideration. The specifications and strength characteristics for the different variants of Alloy 800 were incorporated into draft DIN standards after discussion and approval in expert committees. Further important characteristics of the mechanical and physical material behaviour were summarized in HTR material data sheets so as to furnish an improved basis for the design and stress analyses of Alloy 800 ...

1990-04-01

125

Alloy 800 specifications in compliance with component requirements  

International Nuclear Information System (INIS)

In view of the importance of the material Alloy 800 in high-temperature reactor plants (HTR), a material data bank was established which is used for statistical evaluation of mechanical and physical material behaviour. Based on investigations on the interconnection between the mechanical properties at high temperatures and the metallurgical parameters, different types of Alloy 800 were specified in compliance with the component requirements. In addition, aspects of corrosion and toughness behaviour were taken into consideration. The specifications and strength characteristics for the different variants of Alloy 800 were incorporated into draft DIN standards after discussion and approval in expert committees. Further important characteristics of the mechanical and physical material behaviour were summarized in HTR material data sheets so as to furnish an improved basis for the design and stress analyses of Alloy 800 ...

126

Physiological responses of Pinus sylvestris to changing carbon dioxide and ozone concentrations  

Energy Technology Data Exchange (ETDEWEB)

The objective of this research is to study the effects of elevated ozone, carbon dioxide and their combination on ultrastructural, physiological and biochemical responses of Scots pine needles and how these effects are reflected to photosynthesis, carbohydrate and nutrient allocation and finally to shoot and root growth of trees. In addition the interactions of the studied trees and mycorrhizal fungi as well as insect herbivores are studied. The exposures have been running only for two growing periods and it seems necessary to continue the experiment over the third growing season in 1996. Since the analyses are partially incomplete, only preliminary conclusions are possible at the moment. The slightly increased shoot growth and needle width and increased amount of starch in chloroplasts point to the slight stimulating effect of elevated CO{sub 2} among the chamber treatments. Altogether the growth of the seedlings was best in the chamberless treatment indicating a ...

1996-12-31

127

Thermal dislocation depinning in a deformed crystal  

Energy Technology Data Exchange (ETDEWEB)

The temperature dependence of the dislocation mobility threshold is investigated on the basis of a dislocation model suggested by Frenkel-Kontorova. The critical value is obtained for the stress/temperature, corresponding to the dislocation depinning from its equilibrium position. The universal behaviour of a barrier height at finite stress and temperature is revealed and investigated.

2008-01-14

128

Thermal activation of escape swimming in post-hatching Xenopus laevis frog larvae  

UK PubMed Central (United Kingdom)

SummarySurvival requires the selection of appropriate behavioural responses in the face of danger. With respect to the threat of predation, both the decision to escape and the underlying...Full Text Available

2009-08-01

129

The feasibility of using pattern recognition software to measure the influence of computer use on the consultation  

UK PubMed Central (United Kingdom)

BackgroundA key feature of a good general practice consultation is that it is patient-centred. A number of verbal and non-verbal behaviours have been identified as important to establish...Full Text Available

130

Structural aspects of lithium ions hydration in aqueous solutions of electrolytes  

International Nuclear Information System (INIS)

Analysis of results of an investigation into the structure of lithium salt aqueous solutions is presented. An anomaly in lithium ion behaviour in solutions at the structural level is noted. 40 refs., 3 tabs.

131

Solid state and materials research: metal-semiconductor interactions  

International Nuclear Information System (INIS)

This section of the report is concerned with the study of the metallisation, oxidation and doping of materials which are of importance to the micro-electronics industry. The Van de Graaff accelerator and radioactive tracers are used for studying surface and sub-surface behaviour of these materials.

132

Simulation of solid molecular hydrogen - a new twist to an old problem  

British Library Electronic Table of Contents (United Kingdom)

Solid molecular orthohydrogen exhibits orientational order at low temperatures. The orthohydrogen molecules, which are quadrupoles, order in the Pa3 structure. We have simulated this ordering, and explored the behaviour under dilution by spherical parahydrogen molecules.

2010-01-01

133

Seasonal and Annual Variation in Activity in Wild Male Meadow Voles (Microtus Pennsylvanicus).  

Science.gov (United States)

Project ZEUS was designed to characterize the effects of long-term gamma irradiation on free-ranging meadow voles, and to determine the lowest level of radiation at which biological effects are discernible in the population. Behavioural tests are consider...

1980-01-01

134

Scaling of swim speed and stroke frequency in geometrically similar penguins: they swim optimally to minimize cost of transport  

UK PubMed Central (United Kingdom)

It has been predicted that geometrically similar animals would swim at the same speed with stroke frequency scaling with mass−1/3. In the present study, morphological and behavioural...Full Text Available

2010-03-07

135

QUT | Research news and events  

Wastenet

...Year nine students will be taught the importance of mateship in a bid to reduce risky behaviour and save lives as part of a school-based intervention program to be introduced in Queensland. 24.11.10 Safe sex saves schoolies from chlamydia The safe-sex message is failing to get ...

136

Predictors of healthcare professionals' intention and behaviour to encourage physical activity in patients with cardiovascular risk factors  

UK PubMed Central (United Kingdom)

BackgroundHealthcare professionals can play a crucial role in optimizing the health status of patients with cardiovascular risk factors (abdominal obesity, high blood pressure, low...Full Text Available

137

Maternal effects and range expansion: a key factor in a dynamic process?  

UK PubMed Central (United Kingdom)

Species that depend on ephemeral habitat often evolve distinct dispersal strategies in which the propensity to disperse is closely integrated with a suite of morphological, behavioural and physiological...Full Text Available

2009-04-27

138

Loss of ?-III spectrin leads to Purkinje cell dysfunction recapitulating the behaviour and neuropathology of SCA5 in humans  

UK PubMed Central (United Kingdom)

Mutations in SPTBN2, the gene encoding β-III spectrin, cause spinocerebellar ataxia type 5 in humans (SCA5), a neurodegenerative disorder resulting in loss of motor...Full Text Available

2010-04-07

139

Knowledge and behaviour of nurse/midwives in the prevention of vertical transmission of HIV in Owerri, Imo State, Nigeria: a cross-sectional study  

UK PubMed Central (United Kingdom)

BackgroundMother-to-Child Transmission (MTCT) of HIV remains the main mode of acquisition of HIV in children. Transmission of HIV may occur during pregnancy, delivery or breastfeeding....Full Text Available

140

Is nest-drifting behaviour an insurance policy for maximising indirect fitness in primitively eusocial paper wasps?  

Environmental Research Database

ObjectivesThe main objectives of this project are: 1. To determine whether nest-drifting behaviour allows helpers to maximise their indirect fitness in the paper wasp Polistes canadensis. Specifically, I will test a) whether nest-drifters apportion helping effort in relation to the productivity benefits of different nests (hypothesis 1a), and b) whether nest-drifters can adjust their investment in response to changes in the productivity payoffs of different nests (hypothesis 1b). 2. To determine [continued...]DescriptionDarwin's theory of natural selection predicts that organisms should act selfishly in order to pass on as many of their genes to the next generation as possible. The evolution of social behaviour is a paradox because it requires that some individuals forgo reproduction in order to help raise the offspring of others. Explaining the evolution of helping behaviour in animal societies has been a major focus for ...

2011-01-20

141

Is There a Role for Patent Medicine Vendors in Tuberculosis Control in Southern Nigeria?  

UK PubMed Central (United Kingdom)

Patent medicine vendors (PMVs) are a ubiquitous feature of the informal health sector in Nigeria. A previous study on healthcare-seeking behaviour of persons with chronic cough in southern Nigeria found...Full Text Available

2010-12-01

142

Irradiation damage in superconductors  

International Nuclear Information System (INIS)

Most superconductors are quite sensitive to irradiation defects. Critical temperatures may be depressed, critical currents may be increased, by irradiation, but other behaviours may be encountered. In compounds, the sublattice in which defects are created is of significant importance. 24 refs.

1989-05-08

143

Investigation of natural circulation two-phase flow behaviour in header manifold using CFD code  

Energy Technology Data Exchange (ETDEWEB)

The three-dimensional (3-D), multiphase, computational fluid dynamic (CFD) code FLUENT is used to simulated two-phase flow behaviour in a CANDU header manifold under low (natural circulation) flow conditions. This behaviour was previously inferred from experimental data. The CFD simulations reported here are being used to support these inferences and to obtain a better understanding of phase distribution in the header manifold. The simulations seem to show that the vapor-water mixture models in the FLUENT code do not capture properly phase separation in the header and proper phase branching at the header-feeder connections that have been observed in experiments at low flows. The simulations using discrete-phase model in FLUENT, which tracks the pathlines of the individual vapor bubbles in the water continuum phase, show interesting, complicated and, in some cases, unexpected bubble trajectories from the point of injection of the bubbles at a ...

2006-07-01

144

Interaction effects of ethanol and pyrazole in laboratory rodents  

UK PubMed Central (United Kingdom)

1. Interactions of pyrazole and ethanol were studied in three laboratory test procedures. They included sleeping time in mice, rotor rod balance in rats and lever pressing behaviour of rats. 2....Full Text Available

1971-09-01

145

Influence of vanadium doping on the electrochemical behaviour of MnO{sub 2} rutile; Influence du dopage par le vanadium sur le comportement electrochimique de MnO{sub 2} rutile  

Energy Technology Data Exchange (ETDEWEB)

Vanadium doped manganese bi-oxide has been obtained from a solution containing both cations. The X-ray diffraction of this material indicates a rutile-type phase but the enlargement of some lines supports the existence of several lattice defects. Also the particle size of the doped material is significantly smaller than the one of the non-doped material obtained in the same conditions. The presence of pentavalent vanadium inside the lattice leads to a small amount of trivalent manganese. Electron microscopy shows the existence of defects which have a tendency of becoming well-ordered and to stabilize a sur-structure. At ambient temperature, the electrochemical behaviour of doped manganese bi-oxide is greatly improved when compared to the non-doped phase. This behaviour is due to the presence of numerous lattice defects and to the smaller size of crystallites. In polymer batteries, the behaviour is similar the one of the ...

1996-12-31

146

Impact of Geographical Proximity on Health Care Seeking Behaviour in Northern Oman  

UK PubMed Central (United Kingdom)

Objectives:Despite its impact on health policy, the relationship between geographical proximity and health care seeking has received scant attention in the medical literature. This...Full Text Available

2008-11-01

147

Herding, social influence and economic decision-making: socio-psychological and neuroscientific analyses  

UK PubMed Central (United Kingdom)

Typically, modern economics has steered away from the analysis of sociological and psychological factors and has focused on narrow behavioural assumptions in which expectations are formed on the basis...Full Text Available

2010-01-27

148

From spectral information to animal colour vision: experiments and concepts  

UK PubMed Central (United Kingdom)

Many animals use the spectral distribution of light to guide behaviour, but whether they have colour vision has been debated for over a century. Our strong subjective experience of colour and the fact...Full Text Available

2010-06-07

149

Fourth international seminar on horizontal steam generators.  

Science.gov (United States)

The general objective of the International Seminars of Horizontal Steam Generator Modelling has been the improvement in understanding of realistic thermal hydraulic behaviour of the generators when performing safety analyses for VVER reactors. The main to...

1997-01-01

150

Flucton model with scaling breaking: EMC effect and lepton pair production on nuclei  

International Nuclear Information System (INIS)

The EMS effect is explained in the flucton model as a consequence of scale invariance violation. Nontrivial behaviour of the ratio between structural functions and production cross sections for lepton pairs for different nuclei at x > 1 is predicted.

151

Examination of program exposure across intervention delivery modes: face-to-face versus internet  

UK PubMed Central (United Kingdom)

BackgroundThere has been increasing interest in the ability of the internet to produce behaviour change. The focus of this study was to describe program exposure across three intervention...Full Text Available

152

Estimating Impact Forces of Tail Club Strikes by Ankylosaurid Dinosaurs  

UK PubMed Central (United Kingdom)

BackgroundIt has been assumed that the unusual tail club of ankylosaurid dinosaurs was used actively as a weapon, but the biological feasibility of this behaviour has not been examined...Full Text Available

153

Dual fuel control of a high speed turbocharged diesel engine  

Energy Technology Data Exchange (ETDEWEB)

The modification of a Ford 7600 turbocharged diesel engine to a dual fuel engine using methane as the supplementary fuel has been carried out. The paper describes the preliminary work of dual fuel control. Two systems are examined and their behaviour is presented.

1987-01-01

154

Do insect metabolic rates at rest and during flight scale with body mass?  

UK PubMed Central (United Kingdom)

Energetically costly behaviours, such as flight, push physiological systems to their limits requiring metabolic rates (MR) that are highly elevated above the resting MR (RMR). Both RMR and MR during...Full Text Available

2005-09-22

155

Determinants of Appropriate Child Health and Nutrition Practices among Women in Rural Gambia  

UK PubMed Central (United Kingdom)

Health education and awareness involves providing knowledge about causes of illness and choices to promote a change in individual behaviour and, thus, improves survival of individuals. Studies have,...Full Text Available

2010-04-01

156

Cross-sectional measures and modelled estimates of blood alcohol levels in UK nightlife and their relationships with drinking behaviours and observed signs of inebriation  

UK PubMed Central (United Kingdom)

BackgroundManagement of nightlife in UK cities focuses on creating safe places for individuals to drink. Little is known about intoxication levels as measuring total alcohol consumption...Full Text Available

157

Coordination chemistry and biological activity of 5'-OH modified quinoline-B12 derivatives.  

Science.gov (United States)

The consequences of structural modifications at the 5'-OH ribofuranotide moiety of quinoline modified B12 derivatives are discussed in regard of the coordination chemistry, the electrochemical properties and the biological behaviour of the compound. PMID:21850334

2011-08-18

158

Computer simulation of protein self-association during small-zone gel filtration. Estimation of equilibrium constants.  

UK PubMed Central (United Kingdom)

A simulation is developed that qualitatively describes the small-zone-gel-filtration behaviour of a reversibly associating protein. The results reflect the dependence of the apparent molecular weight...Full Text Available

1981-04-01

159

Computer code analysis of steam generator in thermal-hydraulic test facility simulating nuclear power plant.  

Science.gov (United States)

In the study three loss-of-feedwater type experiments which were preformed with the PACTEL facility has been calculated with two computer codes. The purpose of the experiments was to gain information about the behaviour of horizontal steam generator in a ...

1995-01-01

160

Cluster analysis of behavioural and event-related potentials during a contingent negative variation paradigm in remitting-relapsing and benign forms of multiple sclerosis  

UK PubMed Central (United Kingdom)

BackgroundEvent-related potentials (ERPs) may be used as a highly sensitive way of detecting subtle degrees of cognitive dysfunction. On the other hand, impairment of cognitive skills...Full Text Available

161

Assessing the effectiveness and cost effectiveness of adaptive e-Learning to improve dietary behaviour: protocol for a systematic review  

UK PubMed Central (United Kingdom)

BackgroundThe composition of habitual diets is associated with adverse or protective effects on aspects of health. Consequently, UK public health policy strongly advocates dietary...Full Text Available

162

An introductory view about superluminal frames and tachyons  

International Nuclear Information System (INIS)

An introduction to the properties and behaviour of tachyons is presented. The extension of special relativity to include superluminal frames is discussed and the generalized Lorentz transformation is considered. The consequences of the existence of tachyous for general relativity and astrophysics are also summarised. (W.D.L.).

163

Aggressive behaviour of solid-pseudopapillary tumor of the pancreas in adults: A case report and review of the literature  

UK PubMed Central (United Kingdom)

Solid-pseudopapillary tumor (SPT) is a rare neoplasm of the pancreas that usually occurs in young females. It is generally considered a low-grade malignant tumor that can remain asymptomatic for several...Full Text Available

2008-02-14

164

A note on tribological behaviour of #alpha#-sialon/steel couples under dry conditions  

International Nuclear Information System (INIS)

Advanced structural ceramics are presently used in several tribological applications, such as precision instrument bearings, automotive engine parts and cutting tools inserts. Design and selection of advanced ceramics for these applications require reliable data on the effects of temperature, load and environment on the tribological behaviour of these materials. In the present work, the friction and wear behaviour of colloidally processed and pressureless sintered sialon ceramics with phase (#alpha#) have been studied, aiming at increasing #alpha#-sialon in industrial applications as cutting tools. The friction and wear behaviour of sialon ceramics against steel DIN-Ck45K were investigated using a pin-on-disk tribometer under dry sliding conditions at room temperature, in order to eliminate the contribution of lubricant. The experiments were performed with a constant sliding velocity of 0.5 m/s and a contact stress of 2.85 ...

165

[Special cases of vascular injuries by war projectiles].  

Science.gov (United States)

The author resumes what is actually known about the behaviour of war projectiles in the target (wound ballistics). This is function of their nature, their velocity, their air trajectory. The difference between lesions due to slow moving bullets and these due to projectiles with a high kinetic energy is outlined. The last ones create, through the temporary cavitation effect, lesions at distance from the residual visible tract, particularly in the vascular conduits. The therapeutic conclusions, which derive from those ballistic behaviours, are briefly described in matter of repair of vascular war injuries [Acta chir. belg., 1982, 82, 457-461]. PMID:7148288

166

Thermal degradation and crystallisation studies of reactively compatibilised polymer blends  

British Library Electronic Table of Contents (United Kingdom)

The thermal degradation and crystallisation behaviours of polyamide12/isotactic polypropylene (PA12/PP) blends were studied. Effects of blend ratio and compatibiliser concentration on the thermal degradation properties of the blends were analysed. The activation energy for degradation in compatibilised and uncompatibilised blends computed using Horowitz-Metzger equation was reported. The blend ratio as well as the presence of compatibiliser has significant effect on the thermal stability of the blends. Phase morphology was found to be one of the decisive factors that affected the thermal stability of both uncompatibilised and compatibilised blends. Melting and crystallisation behaviours of the blends in the presence and absence of compatibiliser were evaluated. It was observed that blendin...

2008-01-01

167

The elastic plastic behaviour of a 1/2% Cr Mo V steam turbine steel during high strain thermal fatigue  

International Nuclear Information System (INIS)

High strain fatigue problem in steam turbine. Cyclic stress strain hysteresis loops and stress relaxation behaviour in 16 h dwell period tests. Variation of stress and strain during tests under nominally strain controlled conditions. Definition of test conditions and of criteria for crack initiation and failure. Comparison of reverse bend and push pull failure data. (orig.) 891 RW/orig. 892 RKD.

168

The effect of ductile connectors on the behaviour of timber-concrete composite beams  

British Library Electronic Table of Contents (United Kingdom)

The load-carrying capacity and ultimate deformation capacity of timber-concrete composite systems can be significantly influenced by the ductility of the connection between the two materials. The use of more ductile connections can increase the load-carrying capacity of the composite system as well as its ultimate deformation capacity. In this work, the potential increase that might be expected for these two parameters due to the use of ductile connections will be assessed through numerical simulations, taking the non-linear behaviour of the connections into account. Furthermore, the connection ductility required to achieve the maximum load capacity depends on the mechanical properties of the connection as well as on the geometric and mechanical properties of the composite system. There ar...

2011-01-01

169

On the magnetic behaviour of REBa_2F_7 compounds (RE=Eu, Dy, Ho, Er, Tm and Yb)  

International Nuclear Information System (INIS)

The DC magnetic susceptibility of the REBa_2F_7 compounds was measured by a SQUID magnetometer in the temperature range 5-300 K. Except for Eu, the other compounds show either Curie law or Curie-Weiss law with relatively small values of paramagnetic Curie temperature, #theta#_p, with effective magnetic moments in the range expected of electronic ground state of the trivalent rare earth ion with appropriate J value. The behaviour of Eu is complex. (orig.).

170

On the fatigue threshold behaviour of two ferrite-pearlite microalloyed steels  

Energy Technology Data Exchange (ETDEWEB)

Long crack fatigue threshold ({delta} K{sub th}) and crack closure behaviour of two thermomechanically processed microalloyed (MA) ferrite-pearlite steels are reported. {delta} K{sub th} and crack closure were measured using a dynamic compliance measurement technique. Crack closure was observed at low load ratios (R < 0.5) and the fatigue thresholds decreased with increasing load ratio. In both steels, the closure-free intrinsic threshold ({delta} K{sub eff} {sub th}) was found to be independent of the load ratio. (orig.)

2000-07-01

171

Niobium behaviour in liquid aluminium; Comportamento do niobio em aluminio liquido  

Energy Technology Data Exchange (ETDEWEB)

In this paper we studied the behavior of commercially pure niobium immersed in molten aluminum. The experiments were carried out 800 and 900 deg C during 2 to 128 hours. Chemical and metallographic analyses, as well as microhardness measurements of the niobium specimens were accomplished. An increase of niobium content in the aluminum bath with time was observed. Metallographic observations revealed the formation of Nb Al{sub 3} external intermetallic compound. During dissolution, fragments of this compound settled at the bottom of the crucible. This behaviour was also observed at 900 deg C, nevertheless with higher intensity. (author) 10 refs., 5 figs., 3 tabs.

1996-12-31

172

Neutron irradiation effects in austenitic alloys  

International Nuclear Information System (INIS)

The post (neutron) -irradiation high-temperature tensile and creep-rupture properties, deformation and fracture characteristics of austenitic alloys, particularly solution annealed Type 316 steel, are surveyed and correlated with the damage structures developed as a function of irradiation temperature (and dose). The mechanisms proposed to explain the irradiation-induced changes in properties and behaviour are summarised. The factors responsible for the observed differences in the post-irradiation and 'in-reactor' creep-rupture properties and behaviour of an austenitic steel are discussed in terms of the helium gas and stress driven growth of small intergranular bubbles and the atom plating associated with their growth and coalescence. (author).

1980-03-01

173

Low cycle fatigue behaviour of a 4th generation Ni-base single-crystal superalloy TMS-138  

Energy Technology Data Exchange (ETDEWEB)

Low cycle fatigue (LCF) of a fourth-generation single-crystal (SC) Ni-base superalloy TMS-138 was studied by comparison with a typical third-generation (TMS-75) and a second-generation (CMSX-4) Ni-base SC superalloys. TMS-138 exhibits improved LCF behaviour under a condition of the R ratio of 0 at temperatures of 1073 K and 1173 K. The addition of refractory elements resulted in a remarkable improvement of the LCF properties compared to those of the reference superalloys due to the different microstructure developed in TMS-138. (orig.)

2004-07-01

174

Dependence of laser assisted cleaning of clad surfaces on the laser fluence  

International Nuclear Information System (INIS)

The decontamination factor is studied as a function of laser fluence for three kinds of clad surfaces viz., plain zircaloy, autoclaved zircaloy and SS with cesium as the test contamination. It has been found that the decontamination factor exhibits a maximal behaviour with the laser fluence and its maximum value occurs at different laser fluences in the three cases. The maximal behaviour is attributed to reduced coupling of energy from the laser beam to the substrate due to the initiation of surface-assisted optical breakdown. The results obtained in the experiment carried out in helium environment qualitatively support this explanation (author)

2005-11-01

175

Corrosion and stress corrosion cracking of alloy 800 in water and steam at elevated temperatures  

International Nuclear Information System (INIS)

The importance that must be attached to the phenomenon of stress corrosion cracking of austenitic alloys is emphasized. The relation between chemical composition of various alloys and their sensitivity to cracking is shown with particular reference to the behaviour of Alloy 800. The different effects of alkaline anc chloride environments are discussed. Studies are reported of the general corrosion of Alloy 800 and other alloys in an environment representative of the primary coolant of PWR reactors; and of the behaviour of various alloys (including Alloy 800) in the conditions envisaged for their use for steam generators with superheat up to about 550 deg.C. (U.K.).

176

Auswirkung von Druckeigenspannungen in der Oberflaeche von Dampfturbinen-Scheiben auf das SpRK-Verhalten. Final Report. (Influence of residual compression stresses on the stress corrosion cracking behaviour of turbine rotor disc material. Final report).  

Science.gov (United States)

In this project the influence of residual compression stresses on the stress corrosion cracking behaviour of the turbine disc steel 26 NiCrMoV 14 5 (Rp(sub 0.2) = 850 N/mm(sup 2)) was investigated. The residual compression stresses were produced by shot p...

1988-01-01

177

A supply chain-transport supernetwork equilibrium model with the behaviour of freight carriers  

British Library Electronic Table of Contents (United Kingdom)

This paper presents a supernetwork equilibrium model integrating supply chain networks with a transport network, namely, a supply chain-transport supernetwork equilibrium model. The model takes into account the behaviour of freight carriers and transport network users to endogenously determine the transport costs generated in the supply chain networks. The interaction between transport network and supply chain networks can also be examined. Results of the numerical tests reveal that the improvement of transport network could enhance the efficiency of supply chain networks. The paper makes contributions to modelling of supply chain networks as well as to that of transport networks.

2011-01-01

178

A study of crystalline and stress behavior in oxide films prepared by ion assisted deposition  

International Nuclear Information System (INIS)

One of the main problems related to optical thin film materials used in high power laser environments is the catastrophic damage caused to them due to laser irradiation. While the influence of ion bombardment on the optical properties of oxide thin films is now a well understood subject, the morphology and crystalline behaviour of these films under ion incidence is not so well studied. Hence, it is of great importance to investigate the effects of ion bombardment during growth on the microstructure and crystalline behaviour of oxide materials.

1994-10-24

179

A review of the behaviour of alloy 800 in liquid sodium  

International Nuclear Information System (INIS)

Although there is service experience of Alloy 800 as tubing for superheaters in conventional and nuclear (HTR) power stations and in PWR heat exchangers, there is no corresponding service experience in sodium-cooled fast reactor steam generators. However, some limited experimental studies have been made of corrosion behaviour, and of possible structure modifications and effects on mechanical properties which occur during exposure of this material to a high temperature sodium environment, and these are summarised in the paper. It is concluded that further work needs to be done before Alloy 800 can be confidently endorsed for use as tubing in fast reactor steam generators. (author).

180

Incredible Years Parent Training Support for Nursery Staff Working within a Disadvantaged Flying Start Area in Wales: A Feasibility Study  

Science.gov (United States)

Parenting programmes are effective interventions for preventing and treating conduct problems in young children. Up to 20% of children in disadvantaged areas have conduct disorder. Recent government initiatives such as targeting early years services to designated disadvantaged Flying Start areas in Wales have resulted in increased nursery-care provision for pre-schoolers, yet little has been done to equip nursery staff with effective child behaviour management strategies. The purpose of this non-randomised trial platform study was to establish the feasibility of delivery and the effectiveness of the new Incredible Years Toddler Parent Programme in supporting nursery staff in managing difficult behaviour in the nursery. The Parent Programme is a 12-session (a two-hour session/week) course for carers/parents of children aged one to three years old, which encourages carers to: establish positive relationships with children through play and ...

2010-12-01

181

Materials for power sources to meet military requirements  

Energy Technology Data Exchange (ETDEWEB)

Power source requirements for the military were presented to provide guidelines for research and development planning. Power sources that contain a high amount of energy and are small, light and durable are a common request from military users. Safety, reliability and low temperature performance are also important factors in the selection of power sources, as are cost and energy efficiency. Issues concerning advanced batteries were reviewed with reference to high energy density cathode materials. Various thermoelectric and renewable energy materials were discussed, with reference to recovery and conversion of waste heat. It was suggested that photovoltaic devices could help revolutionize military logistics by modifying energy re-supply requirements. Solid Oxide Fuel Cells (SOFC) were considered in relation to the high price of the ceramic materials required for operation. It was noted that the development of SOFC anodes capable of generating hydrogen from liquid fuels such as methanol ...

2005-07-01

182

Field investigation of radio network usage at the dismounted infantry section level  

Science.gov (United States)

The Soldier Information Requirements Technology Demonstration (SIREQ TD) project is an experimentation program to identify technologies that significantly enhance the performance of our future soldiers. One of the study series involved a 2 x 2 factorial comparison of the benefits of digital maps over paper maps, and the use of radios vs. no radios. Thirty-two Canadian regular force infantry soldiers performed force-on-force tactical assault missions in wooded terrain, with each soldier participating in all four test conditions. The radios were configured to operate in 4 subnets: 1 channel for each of the 2 Assault Groups (4 soldiers on a channel); a Section Commander/2IC channel; and an all-users channel. Note that in the no-radio conditions soldiers still operated the press-to-talk switch to allow recording of communications, but the speaker volume was set to zero. All communications were date/time stamped, identified as to the user and channel, and the audio was ...

2006-06-01

183

EDI as a Treatment Module in Recycling Spent Rinse Waters  

Energy Technology Data Exchange (ETDEWEB)

Recycling of the spent rinse water discharged from the wet benches commonly used in semiconductor processing is one tactic for responding to the targets for water usage published in the 1997 National Technology Roadmap for Semiconductors (NTRS). Not only does the NTRS list a target that dramatically reduces total water usage/unit area of silicon manufactured by the industry in the future but for the years 2003 and beyond, the NTRS actually touts goals which would have semiconductor manufacturers drawing less water from a regional water supply per unit area of silicon manufactured than the quantity of ultrapure water (UPW) used in the production of that same silicon. Achieving this latter NTRS target strongly implies more widespread recycling of spent rinse waters at semiconductor manufacturing sites. In spite of the fact that, by most metrics, spent rinse waters are of much higher purity than incoming municipal waters, recycling of these spent rinse waters back ...

1999-08-11

184

A cohort study of the effects of Vietnam service on testicular pathology of U.S. military workingn> dogs.  

Science.gov (United States)

Using histopathologic diagnoses made on necropsy material from 3,024 military working dogs (MWDs) who died from 1968 to 1973, we analyzed the effect of military service in the Republic of Vietnam on testicular pathology. Among 1,048 MWDs that died in Vietnam and had no reported developmental risk factors for testicular disease, significant excesses of testicular hemorrhage, epididymitis/orchitis, sperm granuloma, testicular degeneration, and seminoma were evident. Among 126 MWDs with prior Vietnam service who died at other duty stations outside Vietnam from 1968 to 1973, significant excesses of testicular degeneration and seminoma were likewise evident. Among 136 MWDs with prior Vietnam service that later died from 1974 to 1980, seminoma continued to be diagnosed in significant excess. In each instance, the odds ratio for the association between Vietnam service and seminoma was 2.0 or greater. Analysis of ever service by Corps Tactical Zones showed significant ...

1995-05-01

185

FEBEX II Project Final report on thermo-hydro-mechanical laboratory tests  

International Nuclear Information System (INIS)

The results of the thermo-hydro-mechanical (THM) study of the FEBEX bentonite performed during FEBEX II are presented. The laboratory test program continued in part with the works carried out during FEBEX I, particularly in activities related to tests aimed to the calibration of the models, the acquisition of parameters by back-analysis and the improvement of the knowledge on the behaviour of expansive clays. But the program has also included tests on new areas: investigations about the influence of the microstructure changes in bentonite, of temperature and of the solute concentration on the behaviour of clay. Besides, several tests were proposed in order to understand the unexpected behaviour observed in the mock-up test, towards the end of year 2. Temperature effects on water retention curves in confined and unconfined conditions were determined, and swelling pressure, hydraulic conductivity and swelling and ...

186

Nonphotochemical Hole-Burning Imaging Studies of in vitro Carcinoma and Normal Cells Utilizing a Mitochondrial Specific Dye  

Energy Technology Data Exchange (ETDEWEB)

Low temperature Nonphotochemical Hole Burning (NPHB) Spectroscopy of the dye rhodamine 800 (MF680) was applied for the purpose of discerning differences between cultured normal and carcinoma ovarian surface epithelial (OSE) cells. Both the cell lines were developed and characterized at the Mayo Clinic (Rochester, MN), with the normal cell line having been transfected with a strain of temperature sensitive Simian Virus 40 Large T Antigen (SV40) for the purpose of extending the life of the cell culture without inducing permanent changes in the characteristics of the cell line. The cationic lipophilic fluorophore rhodamine 800 preferentially locates in in situ mitochondria due to the high lipid composition of mitochondria and the generation of a large negative membrane potential (relative to the cellular cytoplasm) for oxidative phosphorylation. Results presented for NPHB of MF680 located in the cells show significant differences between the two cell lines. The results are interpreted on ...

2002-06-27

187

Nonphotochemical Hole-Burning Imaging Studies of In Vitro Carcinoma and Normal Cells Utilizing a Mitochondrial Specific Dye  

Energy Technology Data Exchange (ETDEWEB)

Low temperature Nonphotochemical Hole Burning (NPHB) Spectroscopy of the dye rhodamine 800 (MF680) was applied for the purpose of discerning differences between cultured normal and carcinoma ovarian surface epithelial (OSE) cells. Both the cell lines were developed and characterized at the Mayo Clinic (Rochester, MN), with the normal cell line having been transfected with a strain of temperature sensitive Simian Virus 40 Large T Antigen (SV40) for the purpose of extending the life of the cell culture without inducing permanent changes in the characteristics of the cell line. The cationic lipophilic fluorophore rhodamine 800 preferentially locates in in situ mitochondria due to the high lipid composition of mitochondria and the generation of a large negative membrane potential (relative to the cellular cytoplasm) for oxidative phosphorylation. Results presented for NPHB of MF680 located in the cells show significant differences between the two cell lines. The results are interpreted on ...

2002-08-01

188

Neurotoxicity of low-dose repeatedly intranasal instillation of nano- and submicron-sized ferric oxide particles in mice  

International Nuclear Information System (INIS)

Olfactory tract has been demonstrated to be an important portal for inhaled solid nanoparticle transportation into the central nervous system (CNS). We have previously demonstrated that intranasally instilled Fe_2O_3 nanoparticles could transport into the CNS via olfactory pathway. In this study, we investigated the neurotoxicity and size effect of repeatedly low-dose (130 #mu#g) intranasal exposure of nano- and submicron-sized Fe_2O_3 particles (21 nm and 280 nm) to mice. The biomarkers of oxidative stress, activity of nitric oxide synthases and release of monoamine neurotransmitter in the brain were studied. Our results showed that significant oxidative stress was induced by the two sizes of Fe_2O_3 particles. The activities of GSH-Px, Cu,Zn-SOD, and cNOS significantly elevated and the total GSH and GSH/GSSG ratio significantly decreased in the olfactory bulb and hippocampus after the nano- and submicron-sized Fe_2O_3 particle treatment (p < 0.05). The nano-sized Fe_2O_3 generally ...

2009-01-01

189

Temperature dependence of a twofold magnetic behaviour of a nanoscopic metal/silicon hybrid system - a comparison between Ni/Si and Co/Si  

Energy Technology Data Exchange (ETDEWEB)

The investigated hybrid nanocomposite consists of a porous silicon template with electrochemically embedded Ni or Co nanostructures and offers magnetic characteristics which can be tailored by the electrochemical process parameters during fabrication. A twofold magnetic behaviour can be observed, a first one due to the spinmagnetism at magnetic fields below the saturation magnetization of the deposited metals and a second non-saturating term at higher fields (>1 T up to 7 T) above the saturation magnetization. In case of Ni deposited within the pores this non-saturating term shows a paramagnetic characteristic and follows exactly the Curie-Weiss law, whereas for Co/porous silicon samples the temperature dependent magnetization shows some deviations from the Curie Weiss law. In this high field region a difference in the temperature dependence between Ni and Co is observed whereas the non-saturating term does not depend on the geometry of the embedded ...

2009-10-15

190

Oxidation of sialon ceramics with widely varying alumina content  

International Nuclear Information System (INIS)

Within the framework of a study on the chemical wear behaviour of sialon ceramics a range of compositions were prepared in which the alumina content was varied from 6 to 77 weight percent. The materials were hot-pressed from alumina and silicon nitride powders to a density of at least 97%. The structure and compositions of the phases occurring in these samples i.e. the O' phase, #beta#'-sialon solid solution and especially the X-phase were thoroughly characterized with respect to structure and composition using electron microprobe and transmission electron microscopy techniques. These results will be discussed in the light of earlier phase diagram studies. Some basic properties such as E-modulus and toughness were measured and related to microstructural features. E-modulus as well as toughness are at a minimum for materials with a high content of the X-phase. Oxidation of the materials was studied at 1300 deg C and 1450 deg C using weight gain measurements and ...

191

Intra-day and regime-switching dynamics in electricity price formation  

Energy Technology Data Exchange (ETDEWEB)

This paper analyses the complex, non-linear effects of spot price drivers in wholesale electricity markets: their intra-day dynamics and transient irregularities. The context is the UK market, after the reforms introduced in March 2001, analysed with an original set of price drivers reflecting economic, technical, strategic, risk, behavioural and market design effects. Models are estimated separately as daily time-series of the 48 half-hourly trading periods. All coefficients exhibit substantial intra-day variation, relating to the heterogeneity of operating plants and market design aspects. This reveals a market responding to economic fundamentals and plant operating properties, with learning and emergent financial characteristics, as well as some strategic manipulation of capacity, most effectively exercised by the more flexible plants. Using regime-switching parameters, the effects of capacity margin and inter-day capacity adjustment are elucidated, suggesting ...

2008-07-15

192

Hepatitis B immunization coverage and risk behaviour among Danish travellers Are immunization strategies based on single journey itineraries rational?  

DEFF Research Database (Denmark)

OBJECTIVES: The authors examine the rationale and efficacy of pre-travel hepatitis B immunization strategies based on itinerary and presumed on-travel risk behaviour. METHODS: A large survey among 26,640 Danes survey provided data on journey lengths and destinations, immunization coverage, risk behaviour and knowledge. RESULTS: The estimated cumulative lifetime stay in endemic areas outside Europe is 4.3 months. The majority of risk situations are involuntary and unforeseeable. The majority of risk situations occur on short-term journeys. 5% nonimmune and 5% short-term travellers experienced at least one risk situation such as injections/operations/tattoos on their journey. The level of knowledge of hepatitis A and B is low. CONCLUSIONS: The rationale and efficacy of current immunization strategies are challenged. Based on the results presented here and the availability of vaccines with long-lasting coverage, the authors find that ...

2009-01-01

193

Depositional behaviour of coal tailings, co-disposed coal washery wastes and loose-dumped coarse reject  

Energy Technology Data Exchange (ETDEWEB)

Coal washery wastes comprise tailings finer than 0.5 to 0.1 mm depending on the sophistication of the washery, and coarse reject, typically finer than 50 mm. Subaerial disposal of coal tailings slurry at about 30% solids by mass results in the formation of a delta with an average slope of about 1 in 100, representing one extreme. The ravelling of coarse reject on loose-dumping, results in an angle of repose slope with an angle of about 37{degree} (1 in 1.3), representing the other extreme. The pumped co-disposal of coal tailings and coarse reject results in the formation of an upper delta with an average slope of about to one in ten, between the two extremes. The depositional behaviour of these three waste streams is discussed and compared. The important depositional and material parameters, and a theoretical description of the processes involved, are also presented. Comparisons are made between the depositional behaviour of the various coal ...

1998-07-01

194

Comparison of sliding friction and wear behaviour of overhead conveyor steels tested under dry and lubrication conditions; Comportamiento frente al desgaste y friccion de aceros empleados en lineas de manutencion aerea ensayados con y sin lubricacion  

Energy Technology Data Exchange (ETDEWEB)

The sliding friction and wear behaviour of different steel qualities were investigated with and without lubrication conditions. Steel qualities tested are normally used in the overhead conveyor system of many industrial fields, like the automotive sector. Sliding wear tests have been conducted by means of a pin-on-disk machine. A 100Cr6 steel similar to that used within the overhead conveyor trolleys has been employed as a pin. Friction coefficient values obtained under lubrication conditions were three times smaller than those obtained without lubrication. The mechanism that controls wear behaviour under lubrication conditions is an abrasive one and the wear values obtained are almost worthless. On the other hand, mechanism controlling wear during non lubrication tests, was a combination of abrasion and adhesion. (Author) 20 refs.

2005-07-01

195

Capacitance behaviour of passive films on ferritic and austenitic stainless steel  

Energy Technology Data Exchange (ETDEWEB)

The electrochemical behaviour of passive films formed on one austenitic stainless steel (AISI 304) and one ferritic stainless steel (AISI 446) in solutions with pH between 0.6 and 8.4 was studied by capacitance measurements and photocurrent spectroscopy. Compositional characterization of the passive films was done by X-ray photoelectron spectroscopy. The capacitance increases with decreasing pH. Doping densities evaluated from Mott-Schottky plots are in the range 2-6 x 10{sup 20} cm{sup -3} and increased with the pH in the neutral/alkaline range while in pH 0.6, values above 10{sup 21} cm{sup -3} were found. The bandgap energy indicates two transitions, at 2.5-2.8 and 3.2 eV. The analytical data reveal that, as the pH increased, the films become enriched in Fe(II) and Fe(III), whereas the Cr(III) gradually decreases. The films formed at very low pH had a behaviour that contrasts with that of the films formed in the neutral/alkaline media. The ...

2005-03-01

196

Capacitance behaviour of passive films on ferritic and austenitic stainless steel  

International Nuclear Information System (INIS)

The electrochemical behaviour of passive films formed on one austenitic stainless steel (AISI 304) and one ferritic stainless steel (AISI 446) in solutions with pH between 0.6 and 8.4 was studied by capacitance measurements and photocurrent spectroscopy. Compositional characterization of the passive films was done by X-ray photoelectron spectroscopy. The capacitance increases with decreasing pH. Doping densities evaluated from Mott-Schottky plots are in the range 2-6 x 10"2"0 cm"-"3 and increased with the pH in the neutral/alkaline range while in pH 0.6, values above 10"2"1 cm"-"3 were found. The bandgap energy indicates two transitions, at 2.5-2.8 and 3.2 eV. The analytical data reveal that, as the pH increased, the films become enriched in Fe(II) and Fe(III), whereas the Cr(III) gradually decreases. The films formed at very low pH had a behaviour that contrasts with that of the films formed in the neutral/alkaline media. The films are ...

2005-03-01

197

An adaptive self-optimizing power system stabilizer  

Energy Technology Data Exchange (ETDEWEB)

A self-optimizing pole-shifting control algorithm has been developed for an adaptive power system stabilizer (APSS) to improve its dynamic performance and autonomous operation. The proposed algorithm deals with the system frequency and time domain characteristics simultaneously to guarantee stability and to enhance the performance of the closed-loop system. The mechanism of discrete control system control limits influencing the closed loop system behaviour is studied. Short-term behaviour is studied by introducing the concept of a short-term behaviour index. With the introduction of dynamic control limits, an effective discrete control system design method is proposed. A PSS oriented power system dynamics simulation package (PSDSP) has been developed. Using the PSDSP, simulation studies were performed with the proposed APSS applied to a single machine and a multi machine power system. The performance of the APSS is ...

1994-01-01

198

Advances on experimental techniques for the characterization of THM behaviour of bentonite  

Energy Technology Data Exchange (ETDEWEB)

The design of high level radioactive waste (HLW) repositories in deep geological media in which bentonite clay is proposed as a sealing material leads to the need of further studying the behaviour of highly compacted expansive soils when subjected to mechanical, hydraulic and thermal changes. Laboratory tests may help to understand the processes that take place in the clay barrier under simple and controlled conditions and to develop the governing equations. The laboratory tests enable to isolate the different processes, making their interpretation easier, and provide with fundamental data concerning the parameters to be used in the models. The extremely low permeability of these materials, their avidity for water (high suction) and their high swelling capacity make necessary the modification of the conventional laboratory techniques and procedures to determine basic physical parameters. The main hydraulic properties of the barrier to be considered are the ...

2005-07-01

199

What is the technical and environmental interest in reusing a recycled polypropylene-hemp fibre composite?  

British Library Electronic Table of Contents (United Kingdom)

The integration of the environmental problem in the design of industrial products leads us to incorporate vegetal fibres and recycled polymers into composite materials. The aim of this work is to study the behaviour and the environmental interest of a recycled PP/hemp fibre after several injection cycles. The mechanical and rheological behaviour of recycled PP/hemp composite was first studied by using tensile, dynamical mechanic analysis and rheological measurements. Then, to better understand the influence of the recycling, a morphology study was carried out on composites by using optical and electron microscopy. Finally, we investigated the environmental advantages of our composite thanks to a simplified environmental assessment. Our results highlighted the environmental interest of usin...

2011-01-01

200

Using Floor Cooling as an Approach to improve the Thermal Environment in the Sleeping Area in an Open Pig House  

British Library Electronic Table of Contents (United Kingdom)

In order to provide pigs a comfortable sleeping area in hot weather, a floor cooling system was designed and applied to production buildings. Experiments were conducted to compare the floor temperatures and to observe the lying behaviour of pigs in the sleeping area of the buildings with and without floor cooling system. The results showed that, without the floor cooling system, the floor temperature was nearly the same as the air temperature in the open pig house. With the floor cooling system, the floor temperature of the sleeping area was controlled at 22-26degreeC, even though the air temperature was as high as 34degreeC, which improved the comfort of the pigs in the sleeping area. The pig lying behaviour was greatly affected by the floor temperature. More than 85% of the pigs were lyi...

2006-01-01

201

The effect of thermal pretreatment on the structure and creep behaviour of the alloy 800 H. Zum Einfluss der thermischen Vorbehandlung auf Struktur und Kriechverhalten des Werkstoffs Alloy 800 H  

Energy Technology Data Exchange (ETDEWEB)

Different cooling speeds after previous solution annealing at 1130deg C for 0.5 hour were simulated in laboratory experiments. The following conditions were examined: (1) Direct water quenching, (2) cooling in air for 0.5 min to 950deg C/water quenching, (3) cooling in air for 1.5 min to 750deg C/water quenching, (4) cooling in furnace for 5 min to 750deg C/water quenching. The results of the investigations have shown that a variation of the cooling conditions causes considerable changes in the creep behaviour. (orig.).

1987-01-01

202

Study on the crystallization behaviour and thermal stability of glass-ceramics used as solid oxide fuel cell-sealing materials  

British Library Electronic Table of Contents (United Kingdom)

Glass ceramics are commonly used as sealing materials for planar solid oxide fuel cells (SOFCs). The major requirements of stack and module builders for these materials are the stability of the coefficient of thermal expansion (CTE), excellent bonding (sticking) behaviour and the absence of volatile ingredients, which can lead to changes of the material properties and the sealing ability. SCHOTT Electronic Packaging has developed special glasses and glass-ceramics for various solid oxide fuel cell designs and operating temperatures. The glass compositions are based on the system MgO-Al2O3-BaO-SiO2-B2O3. In this study the evaluation of the developed materials was done by high temperature aging tests for up to 1000h, high temperature XRD-studies and Rietveld calculations, combined with scann...

2011-01-01

203

Specific features of radiation damage in titanium alpha-alloys  

International Nuclear Information System (INIS)

Titanium base 'alpha'-alloys (Pt-7M, RK-20 and Ti-5Al-2Zr-1.5V) are considered for their behaviour under neutron irradiation. The role of alloying elements in radiation hardening is discussed depending of neutron fluence and irradiation temperature. For PK-20 alloy three stages of change in mechanical properties are revealed which are following: incubation period and weak hardening, intense radiation hardening, radiation hardening attenuation. Irradiation temperature rise results in an increase of incubation period and threshold neutron fluence. A special attention is paid to hydrogen absorption in #alpha#-titanium alloys under irradiation. It is concluded that titanium base 'alpha'-alloys are serviceable as structural materials in nuclear plants with allowance made for peculiar features of their radiation behaviour. 4 refs.; 7 figs.; 1 tab.

204

Review of SCDAP/RELAP5 Code Application to severe accident analysis of CANDU Reactors  

International Nuclear Information System (INIS)

SCDAP/RELAP5 code has been developed in US for best-estimate simulation of light water reactors transients during nuclear accidents. The code models the coupled behaviour of the cooling system, reactor core and fission products release during the accident. It is the result of the coupling between RELAP5, modelling thermal hydraulic, control system, reactor kinetics and the transport of noncondensable gases, and SCDAP code modelling the behaviour of the reactor core during severe accidents. The paper briefly presents the application of SCDAP/RELAP5 code to CANDU severe accident analysis. Also, the paper proposes a summary of the needs for development that could enhance the quality of the severe accidents related predictions in CANDU reactors. (authors)

2009-10-12

205

Review and investigations of oscillatory flow behaviour of a horizontal ceiling opening for nuclear containment and fire safety analysis  

Energy Technology Data Exchange (ETDEWEB)

In the thermal hydraulics codes developed for fire safety analysis and for containment thermal hydraulic analysis, junctions in the multi-compartment geometries is often modeled as uni-directional junctions. However, ceiling junctions are known to depict unstable/oscillatory bi-directional flow behavior. Detailed investigations have been carried out to understand the unstable flow behaviour of a junction by analyzing an earlier reported experiment and its subsequent two dimensional numerical RANS based study of fire in an enclosure. The authors attempt more realistic and desired three dimensional and inherently transient large eddy simulations using a computer code Fire Dynamics Simulator (FDS). The paper presents the details of the analysis, the results obtained and further studies required to be conducted so that the findings can be applied to the fire/containment thermal hydraulics analysis codes successfully. (orig.)

2011-05-15

206

Pseudohalogen compounds of astatine: first syntheses and characterizations of At-rhodanide and At-cyanide compounds  

Energy Technology Data Exchange (ETDEWEB)

At-pseudohalogen compounds with SCN/sup -/ and CN/sup -/ were synthesized at the first time using At(THETA)/sup +/, At/sup 0/ and At/sup -/. Investigations of the electromigration behaviour of these compounds in free electrolytes in dependence on the SCN/sup -/ and CN/sup -/ concentrations and on pH permit deductions about compound formation and hydrolysis behaviour. The formation constant for At(SCN)/sub 2//sup -/ is 4x10/sup 2/ lxmol/sup -1/ at an ion strength of 0.05/sup 2/ molxl/sup -1/. Between pH 7 and 9 hydrolysis takes place resulting in At/sup -/. The same result has been found in the case of the hydrolysis of AtCl/sub 2//sup -/ and AtBr/sub 2//sup -/.

1983-02-09

207

Pseudohalogen compounds of astatine: first syntheses and characterizations of At-rhodanide and At-cyanide compounds  

International Nuclear Information System (INIS)

At-pseudohalogen compounds with SCN"- and CN"- were synthesized at the first time using At(THETA)"+, At_0 and At"-. Investigations of the electromigration behaviour of these compounds in free electrolytes in dependence on the SCN"- and CN"- concentrations and on pH permit deductions about compound formation and hydrolysis behaviour. The formation constant for At(SCN)"2"- is 4x10_2 lxmol"-_1 at an ion strength of 0.05_2 molxl"-_1. Between pH 7 and 9 hydrolysis takes place resulting in At"-. The same result has been found in the case of the hydrolysis of AtCl"2"- and AtBr"2"-. (author).

208

Perceived service quality and self-concept influences on consumer attitude and purchase process: A comparison between physical and internet channels  

British Library Electronic Table of Contents (United Kingdom)

This study aimed to explore the impact of perceived service quality and self-concept on consumer attitude and purchase process using channel type (physical and Internet) as a segmentation variable. From the perspective of consumer behaviour, this study attempted to estimate a relational model and perform an empirical validation using female cosmetics and skincare products as an example. It was discovered that the influence of perceived service quality and self-concept on consumer attitude, purchase intention and behaviour, satisfaction, and loyalty varied with channel type. The analysis result revealed that physical stores presented higher levels of agreement with all research perspectives than Internet stores. However, only two relational paths have a higher influencing effect in physical...

2011-01-01

209

On the mechanism of the anodic protection of aluminium alloy AA5182 by emeraldine base coatings  

Energy Technology Data Exchange (ETDEWEB)

Aluminium AA5182 coupons covered by a polyaniline film in the emeraldine base (EB) form showed increasing corrosion potential and decreasing corrosion current as a function of the thickness of the polymer layer. The cathodic reaction was proved not limited by diffusion of species inside the electrolyte solution and oxygen had no effect on the electrochemical behaviour of the coated samples. An EB coating on indium tin oxide conducting layer appeared slightly electroactive in neutral media. The IR spectra of aluminium coated samples, before and after heating in argon atmosphere, confirmed a redox reaction between the polymer film and the metal. This galvanic coupling can explain the good protective behaviour of emeraldine base against corrosion of aluminium.

2007-03-01

210

Modelling the work flow of a nuclear waste management program  

Energy Technology Data Exchange (ETDEWEB)

In this paper we describe a modelling project to improve a nuclear waste management program in charge of the creation of a new system for the permanent disposal of nuclear waste. SADT (Structural Analysis and Design Technique) is used in order to provide a work-flow description of the functions to be performed by the waste management program. This description is then translated into a number of Coloured Petri Nets (CPN or CP-nets) corresponding to different program functions where additional behavioural inscriptions provide basis for simulation. Each of these CP-nets is simulated to produce timed event charts that are useful for understanding the behaviour of the program functions under different scenarios. Then all the CPN models are linked together to form a single stand-alone application that is useful for validating the interaction and cooperation between the different program functions. A technique for linking executable CPN models is ...

1997-03-01

211

Measurement of the dark matter velocity anisotropy profile in galaxy clusters  

CERN Document Server

Dark matter particles form halos that contribute the major part of the mass of galaxy clusters. The formation of these cosmological structures have been investigated both observationally and in numerical simulations, which have confirmed the existence of a universal mass profile. However, the dynamic behaviour of dark matter in halos is not as well understood. We have used observations of 16 equilibrated galaxy clusters to show that the random velocities of dark matter particles are larger on average along the radial direction than along the tangential, and that the magnitude of this velocity anisotropy is radially varying. Our measurement implies that the collective behaviour of dark matter particles is fundamentally different from that of normal particles and the radial variation of the anisotropy velocity agrees with the predictions of numerical simulation.

2008-01-01

212

Low-cycle fatigue behaviour and microstructure of copper and alpha-brass under biaxial load paths  

Energy Technology Data Exchange (ETDEWEB)

The low-cycle fatigue behaviour of copper and a-brass CuZn30 was investigated in uniaxial and biaxial tests. Planar biaxial fatigue tests were carried out using cruciform samples with proportional stain paths with and without phase shift between the two axes. Microcharacterisation was performed by electron microscopy as well as by high-resolution X-ray line profile analysis. The biaxial cyclic stress-strain curves show good agreement with the uniaxial ones using the von Mises equivalent strain hypothesis. The dislocation densities and microhardness values of the biaxial case, however, show significantly lower values compared to the uniaxial case at equivalent von Mises stresses.

2010-07-01

213

Lithium/polymer batteries. Safety approach of the BT-EDF-CEA project; Accumulateurs lithium/polymere. Demarche securite du projet BT-EDF-CEA  

Energy Technology Data Exchange (ETDEWEB)

The BT-EdF-CEA consortium for the development and the performance improvement of lithium/polymer batteries has carried out a safety analysis of the industrial risk and the risk for users linked with this new technology. The process chosen for the manufacturing of lithium/polymer batteries does not generate any particular risk of personnel or environmental contamination. Security tests have permitted to observe and analyze the behaviour of 4 Ah elements during thermal shocks, perforation and crushing, and during external short-circuit on 20 Ah elements. These tests demonstrate the great thermal stability and the excellent behaviour of batteries in the case of partial destruction. (J.S.) 2 refs.

1996-12-31

214

Language and Music in the Musician Brain  

British Library Electronic Table of Contents (United Kingdom)

Abstract Results of numerous experiments conducted over the past 15-years by using behavioural as well as brain imaging methods have shown that musical expertise influences brain anatomy, brain functions and behaviour. The musician- brain is thus considered as a very good model of brain plasticity. Moreover, many results have demonstrated that musical expertise not only impacts on music processing but also on several aspects of speech processing including lexical pitch, sentence intonation and the metric structure of words. Conversely, recent results indicated that linguistic expertise with tone or quantity languages such as Mandarin Chinese, Thai, Finnish and Japanese, influences the processing of harmonic tones and musical intervals. We discuss possible interpretations of these findings ...

2011-01-01

215

Information-seeking behaviour and coping style of women opting for either implant or DIEP-flap breast reconstruction  

British Library Electronic Table of Contents (United Kingdom)

Background: High satisfaction rates have been reported after autologous breast reconstruction. Yet, most mastectomy patients receive implant reconstructions (ImBR). Independent and active decision makers have shown mainly to choose for autologous reconstructions, such as the Deep inferior epigastric perforator (DIEP) flap (DiepBR). To further explore the decision making to opt for either ImBR or DiepBR, we investigated patient knowledge, informational resources used, effect of plastic surgeons' advice, coping style and personal independence. Methods: A total of 153 women, who were planned for DiepBR or ImBR preoperatively, completed a study-specific and standardised validated psychological questionnaire. Analyses were aimed at information-seeking behaviour, personal independence and coping...

2011-01-01

216

Influence of weather on the behaviour of outdoor-wintered beef cattle in Scandinavia  

British Library Electronic Table of Contents (United Kingdom)

The aim of the present investigation was to study the effect of weather and available protection on the behaviour of outdoor-wintered beef cattle (Bos taurus). A herd of 78-85 cattle head was studied during four winter months in the Southwest of Sweden. Protection was offered by coniferous forest situated on and around the 12ha pasture, which we divided into protection categories. During 240h we observed 10 cows and 10 heifers as focal animals (each 3h/month) during day time and adjusted observation times to the altitude of the sun. Close to the animals and at an unprotected spot of the pasture we measured temperature, wind speed and solar radiation and combined these variables to a single measure called Wind Chill Temperature (WCT). During observations the animals were in the forest in 12...

2011-01-01

217

Influence of the curved geometrical shape on the thin shell buckling phenomenon behaviour  

British Library Electronic Table of Contents (United Kingdom)

The present paper deals with instabilities of long homogeneous and isotropic thin shells, characterized by geometrical non-linearities and imperfections, with reference to a bent helicoidally geometrical shape of particular interest for the helicoidal steam generators tube bundle. Apparently no data exist in the literature to describe the non-linear buckling behaviour of curved thin shells under external pressure, thus, the theoretical analyses based on the classical linear elastic theory, as expected, might be inadequate to evaluate the collapse load especially if the curvature is rather large. To the purpose of determining the buckling pressure load the effects of a pre-existing level of geometrical and technological imperfection, unavoidably caused by various manufacturing processes wer...

2009-01-01

218

Influence of self-doped poly(aniline-co-4-amino-3-hydroxy-naphthalene-1-sulfonic acid) on corrosion inhibition behaviour of iron in acidic medium  

British Library Electronic Table of Contents (United Kingdom)

This paper presents the corrosion inhibition performance of soluble self-doped copolymers of aniline and 4-amino-3-hydroxy-naphthalene-1-sulfonic acid synthesized by chemical oxidative polymerization method. The corrosion inhibition behaviour of the copolymers in 1.0M HCl has been evaluated using Tafel Extrapolation method and electrochemical impedance spectroscopy (EIS) which was also used to propose the mechanism besides surface morphology. The results showed that the copolymer film exhibited the significant shifting in the corrosion potential and greater charge transfer resistance. The corrosion inhibition efficiency was found to increase from 50% to 90% by increasing the concentration of copolymer from 10 to 70mg/l in HCl medium. Moreover, the copolymer showed the larger degree of surf...

2011-01-01

219

High temperature deformation of the Al-5Cr-2Zr alloy as a function of powder particle diameter  

International Nuclear Information System (INIS)

The powder particle size, D, influences the creep behaviour of Al-Cr-Zr alloys. The alloy studied in this work, Al-5Cr-2Zr (mass%), was prepared by argon atomization. Three size fractions of powder particles were selected: 24-50 #mu#m, 50-100#mu#m and 100-200 #mu#m in diameter. They were consolidated by extrusion. Independently of D, the flow behaviour of the alloy can be described by the power law equation. As test temperature increases, the stress exponent n decreases up to a value close to 5. A decrease of D causes an increase of n and delays the alloy degradation at high temperature. (Author) 11 refs.

1998-01-01

220

Evaporation in forced convection of an Ostwaldian permanent laminar film flowing over an isothermal inclined plane surface; Evaporation en convection forcee d'un film liquide mince ostwaldien ruisselant en regime laminaire permanent sur une surface plane isotherme et inclinee  

Energy Technology Data Exchange (ETDEWEB)

The authors study, in forced convection, the evaporation of an Ostwaldian film flowing over an isothermal inclined plane surface to determine the influence of the behaviour index of the liquid on the dynamic and thermal characteristics of liquid-air system. The liquid flow is considered partially two-dimensional whereas for the air it is two-dimensional. The coupled equations with the interfacial conditions are solved using a fully implicit finite differences method. From the study, it appears that the behaviour index influences considerably the transfers which are more important for pseudo-plastic liquids than for dilatant ones. (authors)

2003-12-01

221

Equivalence Checking in Embedded Systems Design Verification  

CERN Document Server

In this report we focus on some aspects related to modeling and formal verification of embedded systems. Many models have been proposed to represent embedded systems . These models encompass a broad range of styles, characteristics, and application domains and include the extensions of finite state machines, data flow graphs, communication processes and Petri nets. In this report, we have used a PRES+ model (Petri net based Representation for Embedded Systems) as an extension of classical Petri net model that captures concurrency, timing behaviour of embedded systems; it allows systems to be representative in different levels of abstraction and improves expressiveness by allowing the token to carry information. Modeling using PRES+, as discussed above, may be convenient for specifying the input behaviour because it supports concurrency. However, there is no equivalence checking method reported in the literature for PRES+ models to the best of ...

2010-01-01

222

Effects of sawtooth crashes on beam ions and fusion product tritons in JET  

Energy Technology Data Exchange (ETDEWEB)

The effect of a sawtooth crash on the radial distribution of the slowing down fusion product tritons and on beams ions, is examined with measurements of the 2.5 MeV and 14 MeV neutron emission line-integrals before and after sawtooth crashes. In deuterium discharges, the 14 MeV neutron production was wholly attributable to burnup of the 1 MeV fusion product tritons from d-d fusion. The local emissivity of 14 MeV neutrons, and hence of the profile of thermalizing tritons, is shown to be only weakly affected by crashes in the discharges studied. This is in contradiction with the apparent behaviour of injected beam ions as deduced from a study of the considerable changes in local emissivity of the 2.5 MeV neutrons. Nevertheless, the behaviour of the fusion product tritons is consistent with the scaling of the beam injected deuterium. 1 ref., 6 figs.

1994-07-01

223

Effect of pressure on the valence state of Yb in YbPd_2Si_2  

International Nuclear Information System (INIS)

The intermediate valent behaviour of YbPd_2Si_2 has been studied under pressure in the temperature range from 1.2 K to 90 K by using the 84 keV Moessbauer transition in "1"7"0Yb. At 54 kbar and 4.2 K we obtain an increase of the electric field gradient (EFG) by a factor of #approx =# 3. In addition, the EFG varies strongly with temperature, in contrast to the behaviour at ambient pressure. At 1.2 K a change of the hyperfine pattern is observed indicating a magnetic character of the Yb ion. These results provide evidence of a pressure induced change of the valence state close to 3+. (orig.).

224

Development of a detailed kinetic model for gasoline surrogate fuels  

Energy Technology Data Exchange (ETDEWEB)

A detailed chemical kinetic model to describe the autoignition of gasoline surrogate fuels is presented consisting of the fuels iso-octane, n-heptane, toluene, diisobutylene and ethanol. Model predictions have been compared with shock tube ignition delay time data for surrogates of gasoline over practical ranges of temperature and pressure, and the model has been found to be sensitive to both changes in temperature and pressure. Moreover, the model can qualitatively predict the observed synergistic and antagonistic non-linear blending behaviour in motor octane number (MON) for different combinations of primary reference fuels (PRFs) and non-PRFs by correlating calculated autoignition delay times from peak pressures and temperatures in the MON test to experimental MON values. The reasons for the blending behaviour are interpreted in terms autoignition chemistry. 37 refs., 11 figs., 4 tabs.

2008-08-15

225

Corrosion behaviour of Alloy 800 in high temperature aqueous solutions: Electrochemical studies  

International Nuclear Information System (INIS)

The anodic behaviour and passivity breakdown of Alloy 800 in aqueous solutions of sodium chloride, sodium sulphate and sodium bicarbonate were studied by electrochemical techniques in the temperature range from 60 C to 280 C. The pitting resistance and pitting morphology of the alloy in chloride plus sulphate and chloride plus bicarbonate mixtures, at 60 C and 280 C, were also examined. Increasing bicarbonate or sulphate additions to chloride solutions shift the characteristic pitting potential of Alloy 800 to higher values, both at low and high temperatures. Changes in pitting morphology were observed in sulphate containing solutions while the morphology of the attack found in bicarbonate containing solutions was similar to that in pure chloride solutions. Finally, no localized or substantial generalized corrosion was detected in pure sulphate or bicarbonate solutions at any temperature. (orig.).

226

Capacitive behaviour and electronic structure of passive films formed on nickel base alloy type Inconel 600; influence of Cr and Fe  

International Nuclear Information System (INIS)

The study of passive films formed on a nickel base alloy type Inconel 600 is performed by capacitance measurements (Mott-Schottky approach). This research is supported by the passivation study of the alloying elements Ni, Cr, Fe and high purity alloys Ni-Cr, Ni-Fe, Ni-Cr-Fe. The results obtained show that the capacitive behaviour of the Inconel 600 in the passive state is similar to that on a p-n heterojunction to which a barrier zone of nickel oxide is added. The individual or combined action of alloying elements on the development of this kind of electronic structure is discussed. (authors). 5 refs., 6 figs.

1994-01-01

227

Behaviour of steam turbine power control of large power plant units in case of network short-circuits  

International Nuclear Information System (INIS)

In order to investigate the behaviour of the turbine control system during strong pendulum motions, an analysis is carried out using a digital computer program by which the reactor, the turbine, the generator and, in a simplified way, the network can be simulated to the necessary degree. Plotter pictures can show the main physical quantities. In all cases, the turbine control system should be able to distinguish between strong pendulum amplitude with acceleration of the rotational angles and sudden release criteria. This demand can be satisfied by a simple adjustment in the Kraftwerk Union turbine control system. Only a few seconds after shut-off of a severe network failure, the turbines are back to their rated power, thus contributing to reliability of supply in this critical network situation. (orig.).

1978-11-24

228

Analysis of steam generator loss-of-feedwater experiments with APROS and RELAP5/MOD3.1 computer codes  

Energy Technology Data Exchange (ETDEWEB)

Three experiments were conducted to study the behaviour of the new horizontal steam generator construction of the PACTEL test facility. In the experiments the secondary side coolant level was reduced stepwise. The experiments were calculated with two computer codes RELAP5/MOD3.1 and APROS version 2.11. A similar nodalization scheme was used for both codes so that the results may be compared. Only the steam generator was modeled and the rest of the facility was given as a boundary condition. The results show that both codes calculate well the behaviour of the primary side of the steam generator. On the secondary side both codes calculate lower steam temperatures in the upper part of the heat exchange tube bundle than was measured in the experiments. (orig.) 4 refs.

1997-12-01

229

Analysis of steam generator loss-of-feedwater experiments with APROS and RELAP5/MOD3.1 computer codes  

International Nuclear Information System (INIS)

Three experiments were conducted to study the behaviour of the new horizontal steam generator construction of the PACTEL test facility. In the experiments the secondary side coolant level was reduced stepwise. The experiments were calculated with two computer codes RELAP5/MOD3.1 and APROS version 2.11. A similar nodalization scheme was used for both codes so that the results may be compared. Only the steam generator was modeled and the rest of the facility was given as a boundary condition. The results show that both codes calculate well the behaviour of the primary side of the steam generator. On the secondary side both codes calculate lower steam temperatures in the upper part of the heat exchange tube bundle than was measured in the experiments. (orig.).

1995-09-10

230

An animal model of social instability stress in adolescence and risk for drugs of abuse  

British Library Electronic Table of Contents (United Kingdom)

There is increasing evidence that adolescence, like early life, is a sensitive period in which ongoing brain development can be influenced by environmental factors. This review describes our use of social instability as a model of mild adolescent social stress, its effects on social interactions and on hypothalamic?pituitary?adrenal function over the course of the procedure and in response to new stressors. The effects of social instability are sex-specific, with qualitative differences between the sexes on HPA function over the course of the stressor procedure, and with greater effects in males on behaviour observed during the social instability and greater effects in females on behavioural responses to drugs of abuse into adulthood, long after the stress exposure. The results from invest...

2010-01-01

231

Ventilation intensity - Influence on the air quality and its calculation method; Die Lueftungsintensitaet - Auswirkung auf die Luftqualitaet und deren Berechnungsmethoden  

Energy Technology Data Exchange (ETDEWEB)

Because of good thermal insulation of advanced energetic buildings and their good airtightness the air hygiene is insufficient. A normal ventilation behaviour by window opening consumes too much heating energy. A calculation method is shown taking into account a required air change number, flow rate and indoor air quality as thermal comfort in the rooms occupied by different number of persons. (GL)

2006-07-01

232

Valence determination in EuM_2X_2 compounds: L_I_I_I-edge versus Moessbauer isomer shift  

International Nuclear Information System (INIS)

A comparative study by Eu-L_I_I_I X-ray absorption and "1"5"1Eu-Moessbauer spectroscopy is presented for the EuPd_2_-_xAu_x Si_2 series. Possible ways to distinguish between mixed-valent behaviour and final-state effects in the L_I_I_I-edge spectra are discussed.

1986-07-07

233

Valence determination in EuM/sub 2/X/sub 2/ compounds: L/sub III/-edge versus Moessbauer isomer shift  

Energy Technology Data Exchange (ETDEWEB)

A comparative study by Eu-L/sub III/ X-ray absorption and /sup 151/Eu-Moessbauer spectroscopy is presented for the EuPd/sub 2-x/Au/sub x/ Si/sub 2/ series. Possible ways to distinguish between mixed-valent behaviour and final-state effects in the L/sub II /I-edge spectra are discussed.

1986-12-01

234

Thermal stability of coke  

Science.gov (United States)

A method is presented for calculating the thermal stability of blast furnace coke over a wide range of sizes, based on a study of the coke behaviour pattern in the blast furnace and the change in its thermo-elastic properties during reheating. Using as an example a Novolipetsk metallurgical plant, the possibility was demonstrated of using the thermal stability index calculated by the proposed method for an unambiguous assessment of the quality of blast furnace coke.

1983-01-01

235

The ageing of CANDU steam generator due to localized corrosion  

International Nuclear Information System (INIS)

The principal types of corrosion are presented which can occur in CANDU steam generator. There are also presented the operation conditions, the specifications referring to the water chemistry and the construction materials of Steam Generator, the factors that have a great influence on the corrosion behaviour during the whole exploitation period of this equipment. The most important elements of CANDU Steam Generator ageing management program are also discussed. (R. P.)

2001-09-17

236

The Friction of Vehicle Brake Tandem Master Cylinder  

International Nuclear Information System (INIS)

The behaviour of an elastomeric seal for vehicle brake Tandem master cylinder is measured and analyzed in temperature and brake fluids changed. Working conditions are simulated for different piston rod velocity and cylinder supply pressure, in temperature rising, brakefluid boundary and Nanoaluminum oxide brakefluid oxide brakefluid lubrication. The result shows that Nanoaluminum oxide brakefluid with its ball shape can highly reduce friction coefficient to avoid seal excessive wear and reduce slick slip in brake applications.

2006-10-01

237

Tensile strength of eutectic, directionally solidified alloys based on the Co-Cr-C-system  

International Nuclear Information System (INIS)

The influence of various alloy elements on tensile strength of the eutectic, directionally solidified superalloy 73 C was determined. The tensile properties of the base alloy has been increased by Al, Y and C as alloying elements, while Ni and Ti showed a decreasing effect (alloy softening). However, ductility and thermo-fatigue behaviour had been influenced in a positive way by these elements. The specific meachanism caused by the different elements are discussed. (orig.).

1981-01-01

238

Telephone communications on a face with two steep machine tracks - tests with the mobile X-phone  

Energy Technology Data Exchange (ETDEWEB)

The author gives an account of tests with the X-phone system. The aim of the tests was to establish the reliability and behaviour of the apparatus mounted on a winning machine and to investigate the possibility of setting up a radio link, without laying an extra wire, between the foot of the tubbing-lined roadway and the winning machine on a steep face. The author describes the face and the test conditions and presents details of the satisfactory test results.

1981-11-01

239

Synthesis, properties and biologic activity of nitro-benzo (B) of thiophene- and 2,3-di-hydro-benzo (B) thiophene-1,1-dioxides  

International Nuclear Information System (INIS)

The purpose of work is systematical studying of benzo (B) of thiophene-1,1-dioxides and their 2,3-di-hydro derivatives behaviour in the reactions of electrophflic, radical, nucleophilic nitration, reduction of nitro group, embodiment of synthesis of N-amino derivatives, investigation of sulfur containing hetero-cyclic compounds, including of residues of some steroids

1998-01-01

240

Study on the behaviour of cryogenic current leads in the overload regime  

Energy Technology Data Exchange (ETDEWEB)

6 mm diameter current leads made of M1, M3 copper and L62 brass are tested for extension of operation range of current leads supplying superconducting devices submerged into the cryostat. Data characterizing the effect of material purity on lead superheating are obtained. A theoretical model permitting to obtain analytical dependences for calculating the current lead maximum temperature is proposed and the possibility of its decrease by increasing current lead diameter in the hot part is considered.

1982-01-01

241

Statistical mechanics and thermodynamics for tachyons  

International Nuclear Information System (INIS)

Momentum- and speed-dependent Maxwell-Boltzmann equilibrium distributions have been derived for tachyons and compared with the corresponding relativistic distributions. This is followed by a calculation of the mean, most probable and r.m.s. speeds for both the relativistic and tachyonic distributions. The ideal gas of tachyons is discussed, including calculations of the internal energy and entropy. In each case a comparison is made with the corresponding bradyonic results. It is found that tachyons behave just like bradyons in the high-temperature limit, but have markedly different behaviour at low temperatures.

242

Socio-economic differences and health seeking behaviour for the diagnosis and treatment of malaria: a case study of four local government areas operating the Bamako initiative programme in south-east Nigeria  

UK PubMed Central (United Kingdom)

BackgroundMalaria is one of the leading causes of mortality and morbidity in Nigeria. It is not known how user fees introduced under the Bamako Initiative (BI) system affect healthcare...Full Text Available

243

Silicon effect on corrosion resistance of austenite stainless steels in strongly oxidizing media containing fluoride and phosphate admixtures  

International Nuclear Information System (INIS)

Paper estimates the corrosion resistance and studies the character of dissolving of silicon-bearing austenite stainless steels in strongly oxidizing media containing phosphate and fluoride admixtures. Corrosion behaviour of the studied steels is determined to depend essentially on the content of admixture or alloying silicon, as well as, on their phase composition in many respects determined by the thermal treatment condition. Refs. 22, figs. 1, tabs. 2.

244

Settlement instrumentation to observe open-pit mine backfill and a prototype foundation in western Canada  

Energy Technology Data Exchange (ETDEWEB)

It is necessary that reclaimed land from open pit mining operations has completely settled before it can be returned to the public domain. This paper reports on instrumentation installed to observe settlement of the spoil and behaviour of a prototype foundation on reclaimed land in Alberta, Canada. 6 refs., 7 figs.

1987-11-01

245

Second international seminar of horizontal steam generator modelling  

Energy Technology Data Exchange (ETDEWEB)

The Second International Seminar on Horizontal Steam Generator Modelling was arranged to continue the international cooperation that was started during the first seminar in March 1991. The main topics of the seminar were: (1) further experimental results on horizontal steam generator behaviour, (2) resent developments in modelling, (3) results on analyses and studies on primary-to-secondary side leakages, and (4) results of the common exercise calculations.

1993-12-31

246

Review of the corrosion resistance properties of Alloy 800 in high-temperature steam  

International Nuclear Information System (INIS)

The investigations carried out on Alloy 800 in aqueous high-temperature environments in France as well as in other countries are reviewed. These studies are mainly concerned with nuclear industry where Alloy 800 can be used as structural material for steam generators of PWR, breeders or HTR. As results referred to in the literature on cracking in caustic environmens do not always agree, a discussion is presented on the matter. The behaviour of Alloy 800 in superheated steam is examined. (Auth.).

247

Research on the liquefaction of lignite by hydrogenation  

Energy Technology Data Exchange (ETDEWEB)

The investigations of lignite hydroliquefaction were aimed at improving reaction control in order to minimize residue and gas portion and hence increase the oil yield. To reach this goal, the process parameters were optimized and various catalysts tested for use in sump phase hydrogenation. Detailed investigations were also carried out on the problem of calcium carbonate agglomeration and the maceral decomposition behaviour of different lignite samples under hydrogenation conditions.

1985-01-01

248

Radiation protection in the operating room  

International Nuclear Information System (INIS)

On the basis of legally provided area dose measurements and time records of fluoroscopic examinations during the operation, radiation doses to medical personnel and patients are evaluated. Adequate radiation protection measures and a careful behaviour in the operating room keep the radiation exposure to the personnel below the maximum permissible exposure. Taking into account the continuous personnel radiation monitoring and medical supervision, radiation hazards in the operating room can be considered low.

249

Organizational factors  

International Nuclear Information System (INIS)

The goal of this lecture is to give an overview of important concepts connected to organisational factors and to provide an understanding of mechanisms by which they can contribute to safe or unsafe behaviour of people. The lecture gives examples of ways to organise work, organisational deficiencies and good practices applied in safety oriented organisations. The lecture also gives an introduction to international work and Finnish national regulation connected to organisation and management. (orig.)

250

On some problems caused by wavelet filtering in calculated spectra  

Energy Technology Data Exchange (ETDEWEB)

It is shown that de-noising a measured time signal by wavelet technique produces a rather good result in time domain, while it has unwanted consequences in spectrum estimation. Therefore it can be used for reconstruction of the picture of the physical process, but it should be avoided, when the aim is to reveal eigenfrequencies or transient behaviour of the spectra.

1999-08-01

251

Numerical calculation of the transient response of transmission systems using the natural spline functions, with applications on high-voltage transmission lines  

Energy Technology Data Exchange (ETDEWEB)

To determine the transient response of linear and time-invariant transmission systems which are only described for discret frequencies, it is possible to find a good functional approximation by means of the generalized impulse method, combined with the most important natural spline-interpolation functions of the first and the third degree. This procedure has been applied to calculate the step response of the transient behaviour of the zero-sequence impedance system of the high voltage transmission line.

1981-10-01

252

Non-linearity of pre-dose response and its effects on TL dating  

Energy Technology Data Exchange (ETDEWEB)

Analytical expressions for thermoluminescence (TL) dating based on the modified Zimmerman model were derived. The non-linear behaviour of TL sensitivity is reexamined and is found to be due to electron capturing competitions in both test-dose excitation and the readout stages. A curve fitting method is proposed to determine the paleodose for the additive dose dating method. The multiple activation technique is also investigated, from which the paleodose should be regarded as an upper limit.

2009-03-15

253

Non-linearity of pre-dose response and its effects on TL dating  

International Nuclear Information System (INIS)

Analytical expressions for thermoluminescence (TL) dating based on the modified Zimmerman model were derived. The non-linear behaviour of TL sensitivity is reexamined and is found to be due to electron capturing competitions in both test-dose excitation and the readout stages. A curve fitting method is proposed to determine the paleodose for the additive dose dating method. The multiple activation technique is also investigated, from which the paleodose should be regarded as an upper limit.

2009-03-01

254

Nanocrystalline materials: Interfaces and mesoscopic correlations studied by neutron scattering  

International Nuclear Information System (INIS)

Nanocrystalline materials can exhibit properties which are considerably different from their coarse-grained counterparts, making them unique for basic or applied research and also very promising for potential applications. The topics which are addressed in the present paper are magnetic properties and magnetic correlations on the nanometer scale, mechanical properties, in particular the influence of grain boundaries on the elastic and plastic behaviour, and vibration models of grain boundary atoms in nanostructured materials. (author)

2001-09-23

255

Model tests on a semi-axial pump turbine  

Energy Technology Data Exchange (ETDEWEB)

Due to their good hydraulic characteristic semi-axial pump turbines are used in the medium head range of pumped storage plants. This paper describes model tests performed on a semiaxial pump turbine model and shows the results of these tests. The aim of the model tests was the optimization of the hydraulic water passage, the measurement of the hydraulic characteristics over the whole operating range, the investigation of the cavitation behaviour, the investigation of the hydraulic forces and torques as well as the proof of the values guaranteed to the customer.

1984-03-01

256

Mobile and Marine Robotics  

Science.gov (United States)

University research group with research areas: * Land based and submersible autonomous robots, (UUVs: AUVs and ROVs); * Controllers, electronics, sensor design and fusion, motion control; * Guidance and navigation of underwater vehicles; * AI, neural networks, fuzzy logic, subsumption control, behaviour based control; * Optical fibre and ultrasonic sensors for proximal object detection; * Robot arm control, visual servoing; * Imaging sonar applications; * Simulator development: UUV simulator; imaging sonar simulator; Aircraft/flight simulator.

2007-07-01

257

Microstructural evolution in several casts of alloy 800 during creep tests  

International Nuclear Information System (INIS)

The creep behaviour of different casts of Alloy 800, supplied by different sources, has been determined in multispecimen furnaces at 650, 750 and 800"0C and at different stress levels up to about 14,000 hs; the environment was initially helium and then air. The microstructural investigations were carried out by transmission electron microscopy. (Auth.).

258

Magnetic properties of heavy rare-earth tungstates  

International Nuclear Information System (INIS)

Measurement of the magnetic susceptibility of powder samples of heavy rare-earth (Tb, Dy, Ho, Er, Tm and Yb) tungstates have been reported in the temperature range 300 to 900 K. Curie-Weiss law behaviour has been observed for all samples. The Curie constant, paramagnetic Curie temperature and magneton number for the magnetic ions have also been evaluated for each material. (author).

1978-12-01

259

Ion conducting interpenetrated lattices for lithium generators; Reseaux interpenetres conducteurs ioniques pour generateurs au lithium  

Energy Technology Data Exchange (ETDEWEB)

Interpenetrated lattices (IPL) are combinations of reticulated polymers linked together by permanent crisscross. This structure is well-adapted to combined highly incompatible pairs of polymers. The in-situ sequential method has been applied successfully to the synthesis of ethylene poly-oxides / poly-siloxanes IPLs. The results concerning the preparation of such lattices and their behaviour as solid polymer electrolytes are presented in this paper. (J.S.) 24 refs.

1996-12-31

260

Investigation into the fatigue behaviour of wood laminates for wind energy converter blade design  

Energy Technology Data Exchange (ETDEWEB)

A thesis is presented on improving the understanding of the fatigue properties of wood and fatigue failure mechanisms in the design of wind turbine blades. Three main areas were researched: the effect of R ratio on fatigue life, the effect of moisture on fatigue life and the development of cumulative damage laws. Tests were carried out on mainly four-ply laminates. Recommendations to future work are outlined. (U.K.).

1987-01-01

261

Influencing factors on ESR dose assessment in irradiated chicken legs  

Energy Technology Data Exchange (ETDEWEB)

Electron spin resonance (ESR) dosimetry of irradiated chicken legs is based on the additive dose or the calibration curve methods. In both cases the practical assumption is made that the behaviour of the chicken bone does not depend on factors such as temperature during irradiation, storage conditions and dose rate. So the aim of the present work was to investigate to what extent the above mentioned factors could influence the post-irradiation dose assessment using the ESR technique. (author).

1996-12-31

262

Influence of relaxation phenomena in liquid phase on magnetic anisotropy of metallic glasses  

International Nuclear Information System (INIS)

It if first shown, that the effective field of uniaxial magnetic anisotropy of Fe-Cr-P-C and Fe-Ni-B-Si system amorphous alloys is reduced with an increase of the source melt isothermal exposure time. The behaviour noted is conditioned by microcoherence and relaxation processes in the nonequilibrium liquid phase after crystal-liquid phase transition.

1996-12-01

263

In situ observation of fatigue crack retardation in banded ferrite?pearlite microstructure due to crack branching  

British Library Electronic Table of Contents (United Kingdom)

This paper reports the results of in situ observation of fatigue crack growth in a ferrite?pearlite steel. Stress intensity factor range (?K) decreasing/increasing and constant-?K fatigue tests have been carried out. In banded pearlite orientation, intense crack branching was observed which leads to fatigue crack retardation. Crack closure during the test was monitored to understand the fatigue crack growth behaviour.

2006-01-01

264

Hydrogen effect or texture and deformation mechanism in #beta#-titanium alloy cold rolling  

International Nuclear Information System (INIS)

The relationships of hydrogen alloyed #beta#-titanium alloy deformation behaviour to its microstructure and texture are investigated. It is shown that plasticity increases and strain induced texture changes at low hydrogen contents (0.1-0.2 mass %). Possible mechanisms responsible for specific features of #beta#-Ti alloy deformation are discussed. The study is made using alloy VT35 doped with hydrogen

1999-09-01

265

Gauge-invariant gravitational wave modes in pre-big bang cosmology  

Energy Technology Data Exchange (ETDEWEB)

The t<0 branch of pre-big bang cosmological scenarios is subject to a gravitational wave instability. The unstable behaviour of tensor perturbations is derived in a very simple way in Hwang's covariant and gauge-invariant formalism developed for extended theories of gravity. A simple interpretation of this instability as the effect of an ''antifriction'' is given, and it is argued that a universe must eventually enter the expanding phase. (orig.)

2010-11-15

266

Fuel cells (part 2)  

International Nuclear Information System (INIS)

The article, following and completing the issues dealt with in part 1 (CH4 Energia Metano, 1/99, p. 7), describe the operating characteristic and construction features of molten carbonate and solid oxide fuel cells (MCFC and SOFC). For the latter type, construction cost are evaluated by various authors and research institutes. The article ends by presenting some tables showing the classification and the main characteristics of various fuel cells, and well as the effect of some gases on the behaviour of some of them.

267

Fast and cyclic deformation and transformation behaviour of hardened phases of the steels X210Cr12 and 100Cr6 containing retained austenite; Zuegiges und zyklisches Verformungs- und Umwandlungsverhalten von gehaerteten restaustenitbehafteten Werkstoffzustaenden der Staehle X 210 Cr 12 und 100 Cr 6  

Energy Technology Data Exchange (ETDEWEB)

Alloyed steels containing retained austenite after martensitic hardening are widely applied in technical practice. Although many practical investigations have been made into the mechanical behaviour of composite microstructures with retained austenite, there is still a lack of knowledge concerning their fatigue and crack propagation behaviour. For this reason, the author investigated the effects of retained austenite concentration and stability on the transformation and deformation behaviour of hardened states of the steels X210Cr12 and 100Cr6. For this purpose, monotone tensile tests, cyclic tensile pressure tests, and supplementary crack propagation experiments were carried out. The concentrations of retained austenite were varied between 10 and 100% by volume by means of different heat treatments. [Deutsch] Legierte Staehle, die nach martensitischer Haertung noch Restaustenit enthalten, finden in der technischen Praxis ...

1995-11-01

268

Effects of electric field on the II-III phase transition in lithium ammonium sulphate and its deuterated analogue  

International Nuclear Information System (INIS)

Experimental results are presented on the quasi-statistic polarization reversal and on the effect of high dc electric field on the behaviour of LiNH_4SO_4 and LiND_4SO_4 monocrystals, namely in the vicinity of the II-III phase transformation.

1984-03-01

269

Effectiveness of information provision in reducing risks to the environment  

Environmental Research Database

DescriptionAs part of a wider effort to develop new approaches to evaluating and quantifying the benefits of chemicals regulation, this project will review the effectiveness of existing information provision tools (such as classification and labelling for hazardous properties) in terms of affecting user behaviour. As some EC legislation relating to regulation of chemicals has been in place for some time, an assumption is made that the information provided by it is leading to an improvement in the way chem [continued...

2005-01-30

270

Effect of grain boundary microstructures of brittle fracture in polycrystalline molybdenum  

Energy Technology Data Exchange (ETDEWEB)

Superplasticity can be generally achieved by grain boundary sliding (GBS). The GBS in polycrystalline materials sometimes accompanies with intergranular fracture because of stress concentrations at triple points and/or GB irregularities. To develop the superplastic flow, it is necessary to suppress the intergranular cracking. In the present study, therefore, polycrystalline molybdenum with distinct GB microstructures, such as grain boundary character distribution (GBCD), has been employed to clarify the relationship between fracture behaviour and GB microstructures. Microstructures were analyzed using a FE-SEM/EBSP/OIM system prior to 4-points bending tests at 77K, thereafter, crack propagation was observed. The main results obtained are as follows. Stress fluctuations on stress - strain curves were observed for specimens with random oriented grains, whereas such behaviour rarely occurred for ones with textured grains. Difference in the ...

1999-07-01

271

Dynamic performance testing of control valves  

International Nuclear Information System (INIS)

Response of control valves plays an important role in the dynamics of the flow system as a whole. Knowledge of its transfer function would facilitate analysis of the behaviour of the system. This paper presents the application of Levy's complex curve fitting method for determination of the transfer function of control valves used in Liquid Zone Control System of 540 MWe PHWR. (author)

2005-02-01

272

Dynamic behaviour of dc double anode plasma torch at atmospheric pressure  

International Nuclear Information System (INIS)

An original dc double anode plasma torch which provides a long-time and highly stable atmospheric plasma jet has been devised for the purpose of hazardous waste treatment. The arc fluctuations and dynamic behaviour of the argon and argon-nitrogen plasma jets under different operating conditions have been investigated by means of classical tools, such as the statistic method, fast Fourier transform (FFT) and correlation analysis. In our experiments, the takeover mode is identified as the fluctuation characteristic of the argon plasma jet while the restrike mode is typical in the argon-nitrogen plasma dynamic behaviour. In the case of pure argon, the FFT and correlation calculation results of electrical signals exhibit the only characteristic frequency of 150 Hz, which originates from the torch power and is independent of any change in the operating conditions. It indicates that the nature of fluctuations in an argon plasma jet is mainly induced ...

2007-07-07

273

Dry storage concepts and their thermodynamic layout  

International Nuclear Information System (INIS)

The two favourable dry storage concepts being under consideration in the Federal Republic of Germany are presented and the physical behaviour or natural convection cooling with air is explained. With the three examples cask store, vault storage horizontally and vertically arranged the main thermodynamical design parameters and their influence on the efficiency of the cooling system and on the temperature distribution inside the store and of the stored material are discussed. Moreover, the importance of the fulfilment and the harmony of all safety criteria and the difficulties while to do so are carried out especially with the vault store.

274

Determination of reactor kinetic parameters in a two-core reactor  

Energy Technology Data Exchange (ETDEWEB)

The kinetic parameters, ..cap alpha.. the coupling coefficient and tau-bar the mean neutron transit time have been determined using a reactor oscillator on the coupled-core of the Queen Mary College research reactor. By using correlation techniques it has proved possible to use detectors small enough to be inserted in the fuel tanks. It is shown that the simplified Baldwin model with one-group diffusion theory is inadequate to describe the kinetic behaviour and the experimentally-determined parameters are dependent upon the positioning of the detectors.

1982-01-01

275

Corrosion of materials. A tabular survey. Korrosionsverhalten von Werkstoffen. Eine tabellarische Uebersicht  

Energy Technology Data Exchange (ETDEWEB)

This compact book of tables attempts to give practicians a survey of the corrosion behaviour of common structural and coating materials. Corrosion resistances are presented for steels, alloys, plastics, elastomers, graphite, glasses, and stoneware in environments of NaOH, HNO{sub 3}, SO{sub 2}, ZnCl{sub 2}, NH{sub 3}, H{sub 2}O{sub 2}, ethyl chloride, sodium acetate, and many others. (MM).

1990-01-01

276

Constitutive modeling of a nickel base superalloy -with a focus on gas turbine applications  

Energy Technology Data Exchange (ETDEWEB)

Gas turbines are used where large amounts of energy is needed, typically as engines in aircraft, ferries and power plants. From an efficiency point of view it is desirable to increase the service temperature as much as possible. One of the limiting factors is then the maximum allowable metal temperatures in the turbine stages, primarily in the blades of the first stage, that are exposed to the highest gas temperatures. Specially designed materials are used to cope with these severe conditions, such as the nickel base superalloy IN792. In order to be able to design the components for higher temperatures and tighter tolerances, a detailed understanding and computationel models of the material behaviour is needed. The models presented in this work have been developed with the objective of being physically well motivated, and with the intention of avoiding excessive numbers of parameters. The influence of the parameters should also be as easy as possible to interpret. ...

2003-05-01

277

Characterization of polluted sites. Assessment of pollutant behaviour and transfer in mediums; Caracterisation des sites pollues. L`evaluation du comportement et du transfert des polluants dans les milieux  

Energy Technology Data Exchange (ETDEWEB)

After a presentation of methods and tools for the basic and extensive characterization of polluted sites and the study of evolution and transfer of current organic pollutants in the ground, the example of the rehabilitation of an old Rhone-Poulenc site (at Chauny, France) polluted with metals and arsenic, is described: soil and aquifer diagnosis, risk analysis and determination of migration schemes

1996-12-31

278

Calculation of fission product behaviour in a station blackout accident of Daya Bay Nuclear Power Plant  

International Nuclear Information System (INIS)

The early accident Sequence of the Station Blackout accident is simulated for Daya Bay Nuclear Power Plant, using MELCOR code. The radioactivity of main fission products was derived after calculating the source term in containment. The data will be used for Daya Bay NPP PSA analysis

2002-12-01

279

Bibliographic study on molybdenum biokinetics. Literaturstudie zur Biokinetik von Molybdaen  

Energy Technology Data Exchange (ETDEWEB)

This bibliographical study compiles and analyzes findings about the metabolism and resorption of molybdenum. Besides including studies on the physiology of molybdenum 99, a general survey is given on molybdenum in the environment and on its physiological behaviour. In particular, information on the dependence of molybdenum resorption on various factors, such as the chemical form, antagonisms etc., are gathered from literature. These factors have to be considered for sensibly carrying out necessary experiments.

1988-05-01

280

Asymptotic freedom of Yang-Mills theory with gravity  

CERN Document Server

We study the high energy behaviour of Yang-Mills theory under the inclusion of gravity. In the weak-gravity limit, the running gauge coupling receives no contribution from the gravitational sector, if all symmetries are preserved. This holds true with and without cosmological constant. We also show that asymptotic freedom persists in general field-theory-based gravity scenarios including gravitational shielding as well as asymptotically safe gravity.

2011-01-01

281

Application of strength hypotheses in the creep range under multiaxial stresses  

International Nuclear Information System (INIS)

The applicability of conventional strength hypotheses in the long-term creep range was examined by means of multiaxial loaded small and large-scale specimens of 1% CrMoNiV-steel at 550deg C. The experimentally determined deformation behaviour in the primary and secondary creep range was simulated by means of a finite element analysis. The creep deformation capacity is influenced by the degree of multiaxiality. The validity of a strength hypothesis depends on the type of load and on deformation resp. failure criteria. (orig.).

282

A phenomenological interpretation of trace impurity transport  

Energy Technology Data Exchange (ETDEWEB)

An interpretive theory of trace impurity transport in tokamaks is presented. It is based on an earlier phenomenological approach developed by the authors for describing tokamak plasma transport experiments. The present model is used to explain disparate phenomena observed in ALCATOR C and DITE in a unified phenomenological framework. Predictive numerical calculations are presented for DITE conditions. If experimentally confirmed, the model could be used to correlate plasma properties with trace impurity behaviour. (orig.)

1989-10-01

283

26 years of operating experience with a boiler drum manufactured from a high-temperature copper-nickel-molybdenum steel. 26 Jahre Betriebserfahrungen mit einer Kesseltrommel aus einem warmfesten Kupfer-Nickel-Molybdaen-Stahl  

Energy Technology Data Exchange (ETDEWEB)

The creep behaviour of boiler drums of CuNiMo steels depends on the ratio of the alloys, the heat treatment and the processing technology. Reduction in deformability must be expected but, under optimum conditions, this does not lead to a critical material condition. The appropriate material tests are indispensable. (orig.)

1993-05-01

284

Large eddy simulation of pulsating pool fire  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: General simulation objectives of any fire analysis are macroscopic in nature and deals with the grass data in respect of fire/smoke spread, structural behaviour, environmental conditions etc. However, the accuracy of predicting such macroscopic parameters is a strong function of several other microscopic parameters which govern the overall macroscopic behaviour. Some of the microscopic parameters of interesting such analysis could be buoyancy induced stable/unstable flows, relative flame behaviour, baroclinic velocity distribution etc. Only the field based fire modelling approach is capable of calculating several of these by way of detailed CFD based field modelling. One of the best known tool that could be employed for such studies is the Fire Dynamics simulator (FDS) from NIST with its popular LES based fire modelling approach. Advanced LES based fire modelling scores over the ...

2005-07-01

285

Operating and commissioning experience with the Dortmund-Derne and Brilon plants; Betriebs- und Inbetriebnahme-Erfahrungen mit den Anlagen Dortmund-Derne und Brilon  

Energy Technology Data Exchange (ETDEWEB)

Initially, the decision of the operator in Dortmund-Derne to select the impact-type separator concept is explained. None of the tenderers for this 52 t/h boiler could supply references for this fluidized bed steam generator concept with staged combustion in a high-expansion fluidized bed. Under the circumstances, the simple configuration of the Steinmueller fluidized bed steam generator, its compact construction, the reduced amount of refractory and the operational behaviour of the boiler resulting therefrom were decisive in the operator`s decision to select this concept. The development schedule shows the individual stages from cold and hot trials in various test rigs and pilot plants to the final design. So far, this fluidized bed steam generator concept has been realized in the plants Derne (52 t/h), commissioned in November 1989, and Brilon (100 t/h), commissioned in November 1990. The discussion on the essential design features points out to the deliberate ...

1992-12-31

286

Behaviour of heat resistant power plant steels undergoing variable long term loading conditions  

Energy Technology Data Exchange (ETDEWEB)

High temperature components of power plants are in many cases subjected to variable loading conditions such as cyclic creep or strain cycling. Therefore the cyclic behaviour of important heat resistant steels has been investigated under stress control and to a smaller extent under strain control. The behaviour under cyclic creep rupture conditions was determined in long term experiments covering a wide range of loading conditions. This behaviour can be described with the modified life fraction rule and a factor concept of relative life for single stage cycles and additionally with a multistep hypothesis for multi-stage cycles. The description can be adapted to estimate the life consumption under service type random conditions. The strain cycling behaviour was investigated in regard to the conditions of the heated surface of large components. To simulate this type of loading and to generate long term ...

2000-01-01

287

comparative study of the electrochemical behaviour of iron in alkaline media containing red mud and grey slurries. the effect of Al"3+  

International Nuclear Information System (INIS)

Red mud (RM) is the main by-product of the Bayer process for alumina extraction from bauxite, and grey slurries (GS) are generated during the granite rocks transformation processes. the huge volume of those wastes generated every year suppose a serious environmental problem. Recent works by our group demonstrate the efficiency of both types of muds as corrosion inhibitors for iron and steel in alkaline media containing chlorides. The elemental analysis of these slurried shows that Al"3+ is the main common element. Therefore, the aim of this paper is to study the effect of the soluble Al"3+ in the electrochemical behaviour of iron in alkaline media, in presence and absence of chlorides. The electrochemical study using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) together with surface analysis techniques allowed to conclude that Al"3+ blocks the surface of steel in alkaline media chloride increasing the steel resistance to chlorides ...

288

Wear properties of steel plasma nitrided at high temperatures  

Energy Technology Data Exchange (ETDEWEB)

The wear behaviour of 722M24 (En40B) steel plasma nitrided at high temperatures for long durations was investigated. Under dry sliding and abrasive-containing lubricated conditions, the wear characteristics of the steel were studied as a function of load, time and white layer thickness. The white layer and the wear debris were characterized by X-ray diffraction. The topography of the wear surface was examined in a scanning electron microscope. The plasma nitriding process was carried out using a 20 kW plasma processing unit in cracked ammonia atmosphere. Treatment times of up to 100 h were employed with temperatures of 550, 570 and 590 C. Wear tests were performed with plasma nitrided AMS 6472 as the counterface material. The tests under abrasive-containing lubricated conditions were carried out with 10% carborundum powder 10 [mu]m in size in SAE-30 machine oil. The wear resistance of the steel was improved by plasma nitriding and the abrasive wear resistance of ...

1993-08-30

289

Viscoplasticity of elastomeric materials: experimental facts and constitutive modelling  

Energy Technology Data Exchange (ETDEWEB)

A characteristic of filled elastomers is their ability to undergo very large deformations without damaging their internal structure. The material behaviour is mainly elastic, however, elastomers show hysteresis effects leading to damping properties, which are quite important as regards their applications in various fields of mechanical engineering.A series of experiments (tension, torsion and combinations of both) was carried out on cylindrical bars made of a carbon-black filled rubber mixture. In addition to a pronounced nonlinear rate-dependence, relaxation and viscosity properties are observed as being influenced by the process histories.The behaviour of elastomeric materials is modelled on the basis of a free energy function and evolution equations for additional internal variables. Incorporating or disregarding the very small rate-independent hysteresis, the constitutive modelling may be classified under viscoplasticity or viscoelasticity. ...

2001-03-01

290

The influence of copper and chromium on the semiconducting behaviour of passive films formed on weathering steels  

Energy Technology Data Exchange (ETDEWEB)

The influence of small amounts of alloying elements (0.36% Cu and 0.47% Cr) on the semiconducting properties of passive films formed on weathering steels was investigated either in tetraborate/boric acid buffer solution (pH 9.2) or artificial atmospheric environment (SO{sub 2}-containing environment). The electrochemical behaviour was assessed by potentiodynamic polarisation, capacitance measurements and photoelectrochemistry. The chemical characterisation of the films was carried by Auger electron spectroscopy. The polarization results obtained in the buffer solution show that the addition of chromium decreases the passive current density. The capacitance results show that the films behave as an n-type semiconductor with shallow and deep donor levels situated in the forbidden gap. The presence of copper seems to affect the density of the shallow and of the deep donor levels in the forbidden gap, and as chromium, it also decreases the doping density in the case of ...

2006-12-05

291

The influence of copper and chromium on the semiconducting behaviour of passive films formed on weathering steels  

International Nuclear Information System (INIS)

The influence of small amounts of alloying elements (0.36% Cu and 0.47% Cr) on the semiconducting properties of passive films formed on weathering steels was investigated either in tetraborate/boric acid buffer solution (pH 9.2) or artificial atmospheric environment (SO_2-containing environment). The electrochemical behaviour was assessed by potentiodynamic polarisation, capacitance measurements and photoelectrochemistry. The chemical characterisation of the films was carried by Auger electron spectroscopy. The polarization results obtained in the buffer solution show that the addition of chromium decreases the passive current density. The capacitance results show that the films behave as an n-type semiconductor with shallow and deep donor levels situated in the forbidden gap. The presence of copper seems to affect the density of the shallow and of the deep donor levels in the forbidden gap, and as chromium, it also decreases the doping density in the case of the ...

2006-12-05

292

The electron diffraction: a prime technique to characterize the behaviour of the Li{sub 1-x}C{sub y} / Li{sub x}NiO{sub 2} positive electrode; La diffraction electronique: une technique de choix pour caracteriser le comportement de l`electrode positive Li{sub 1-x}C{sub y} / Li{sub x}NiO{sub 2}  

Energy Technology Data Exchange (ETDEWEB)

LiNiO{sub 2} is one of the most promising material for positive electrodes of lithium-ion batteries. However, its behaviour during cycling and the existence of several phase transitions induced by the lithium ions de-intercalation process has not been explained so far. A transition electron microscopy study of various Li{sub x}NiO{sub 2} (0.25

1996-12-31

293

The effect of temperature on the passive film properties and pitting behaviour of a Fe-Cr-Ni alloy  

Energy Technology Data Exchange (ETDEWEB)

The effect of temperature (60-280{sup o}C) on the properties of the oxide films formed on Alloy 800 in 0.1 M NaCl and 0.1 M Na{sub 2}SO{sub 4} aqueous solutions was studied by in situ AC impedance spectroscopy and polarization in the Fe(CN{sub 6}){sup -3}/Fe(CN){sub 6}{sup -4} redox system. The anodic behavior under the same experimental conditions was examined by potentiodynamic polarization techniques. In both solutions the passive film was found to become more porous, and hence less protective, with increasing temperature. However, at temperatures above 150{sup o}C, the loss of film protectiveness is more pronounced in chloride solutions, in which pitting occurs. Pitting morphology was found to be strongly temperature dependent: isolated and deep pits were found up to 200{sup o}C whereas at higher temperatures a broad, shallow and more generalized type of attack was detected. No effect of temperature on the defect structure of the semiconductor oxide film was found. It was concluded ...

1996-06-01

294

The behaviour of iron in the formation of #beta#'-sialon from a fireclay  

International Nuclear Information System (INIS)

The carbothermal reduction of clay minerals in a nitrogen atmosphere is a well established method for producing #beta#'-sialon. There has been some debate within the literature concerning the role that Fe plays in the formation of the #beta#'-sialon phase. However, most workers accept that Fe is able to either catalyze or promote the formation of #beta#'-sialon although some workers have indicated that the function of the Fe is controlled by gas flow rate and there is evidence that Fe also promotes formation of additional phases. The aim of the present study was to characterize the behaviour of Fe within the #beta#'-sialon synthesis. "5"7Fe Moessbauer spectroscopy was employed for the study because this technique is specific to Fe and does not suffer interference from other elements. Moreover, both the coordination and oxidation state and the relative abundances of the various Fe-containing phases are able to be monitored. A previous Moessbauer study of Fe in ...

295

Solvent extraction using tetracycline as complexing agent Pt. 14. Study of the behaviour of tetracycline as an extracting agent for some fission products  

Energy Technology Data Exchange (ETDEWEB)

The behaviour of tetracycline as an extracting agent for Sr, I, Ba, Mo, Tc, Zr, Nb, Cs, Ru, Te and U was studied and the influence of the acidity of the aqueous phase upon extraction of the elements mentioned was examined. Experiments were made to determine whether the species extracted into the organic phase is the complex formed between tetracycline and the elements considered and to determine the time of shaking necessary so that the equilibrium between the phases is attained. As a practical application, the possibility of using the tetracycline-benzyl alcohol system for separating the fission products sup(137)Cs, sup(140)La, sup(141)Ce, sup(103)Ru, sup(95)Nb from each other and from uranium is presented. The same study was made for sup(131)I, sup(99m)Tc, sup(99)Mo, sup(132)Te, sup(239)Np and uranium and the steps necessary for the separation of these elements are proposed.

1985-10-01

296

Simultaneous harvesting of straw and chaff for energy purposes : influence on bale density, yield, field drying process and combustion characteristics  

Energy Technology Data Exchange (ETDEWEB)

The potential to increase the productivity of fuel straw harvest and transportation was examined. When harvesting straw for energy purposes, only the long fraction is currently collected. However, technological improvements have now rendered it possible to harvest chaff, thus increasing the amount of harvest residues and bale density. The purpose of this study was to determine how harvest yield, bale density, field-drying behaviour and combustion characteristics are affected by the simultaneous harvest of straw and chaff. Field experiments were conducted in 2009 for long- and short-stalked winter wheat crops. Combine harvesting was carried out with 2 different types of combine harvesters. A high-density baler was used to bale the crop residues. Mixing chaff in with the straw swath by combine harvesting gave a lower initial moisture content compared with straw only. The density and the weight of each bale were not affected by the treatments. However, the added chaff ...

2010-07-01

297

Simulation of electromechanical and thermomechanical loads on first wall mock-ups  

International Nuclear Information System (INIS)

In order to study the boundary conditions for the occurrence of ratcheting, a testing rig was erected. In this rig, small-scale mock-ups of the first wall were tested under mechanical conditions similar to those expected during disruptions. These mock-ups were made of stainless steel AISI 316. They were heated on the surface and water cooled from inside. Disruption forces were simulated by a high-speed hydraulic bending system by impact loads. The mock-ups were heated by a high-frequency generator and cooled by water through two cooling channels.In addition to the experimental work, simplified analytical analysis and numerical calculations were carried out using the finite element program ABAQUS. In these calculations, the temperature and stress fields in the mock-ups were investigated and the influence of the different constitutive equations was studied.The experimental results confirm the ratcheting behaviour predicted by the calculations. It has been ...

298

Semiconductor properties and protective role of passive films of iron base alloys  

Energy Technology Data Exchange (ETDEWEB)

Semiconductor properties of passive films formed on the Fe-18Cr alloy in a borate buffer solution (pH = 8.4) and 0.1 M H{sub 2}SO{sub 4} solution were examined using a photoelectrochemical spectroscopy and an electrochemical impedance spectroscopy. Photo current reveals two photo action spectra that derived from outer hydroxide and inner oxide layers. A typical n-type semiconductor behaviour is observed by both photo current and impedance for the passive films formed in the borate buffer solution. On the other hand, a negative photo current generated, the absolute value of which decreased as applied potential increased in the sulfuric acid solution. This indicates that the passive film behaves as a p-type semiconductor. However, Mott-Schottky plot revealed the typical n-type semiconductor property. It is concluded that the passive film on the Fe-18Cr alloy formed in the borate buffer solution is composed of both n-type outer hydroxide and inner oxide layers. On the ...

2007-01-15

299

Semiconductor properties and protective role of passive films of iron base alloys  

International Nuclear Information System (INIS)

Semiconductor properties of passive films formed on the Fe-18Cr alloy in a borate buffer solution (pH = 8.4) and 0.1 M H_2SO_4 solution were examined using a photoelectrochemical spectroscopy and an electrochemical impedance spectroscopy. Photo current reveals two photo action spectra that derived from outer hydroxide and inner oxide layers. A typical n-type semiconductor behaviour is observed by both photo current and impedance for the passive films formed in the borate buffer solution. On the other hand, a negative photo current generated, the absolute value of which decreased as applied potential increased in the sulfuric acid solution. This indicates that the passive film behaves as a p-type semiconductor. However, Mott-Schottky plot revealed the typical n-type semiconductor property. It is concluded that the passive film on the Fe-18Cr alloy formed in the borate buffer solution is composed of both n-type outer hydroxide and inner oxide layers. On the other ...

2007-01-01

300

Safety assessment and life time management of nuclear power plants: from reasonable design to reliable structural health monitoring  

International Nuclear Information System (INIS)

Nowadays the safety of Nuclear Power Plants is becoming more and more significant. Therefore consideration of severe accidents shall be included in both design and operating process of Nuclear Power Plants. In particular ground motion forms one of the important natural hazards. For structural analysis both linear-elastic and non-linear methods are specified by the engineering codes for earthquake resistance design. However, time history analysis is required for investigation of non-linear structural behaviour. Moreover, non-linearities are often caused by the presence of damage. This can be detected by means of structural health monitoring and subsequently system identification. In this paper the advantages of both dynamic time history analysis and damage detection by means of wavelet analysis are discussed. First, the non-linear behaviour of a frame structure due to an artificial earthquake motion is analyzed. A comparison to non-time history ...

2005-06-15

301

SYVAC3 manual  

Energy Technology Data Exchange (ETDEWEB)

SYVAC3 (Systems Variability Analysis Code, generation 3) is a computer program that implements a method called systems variability analysis to analyze the behaviour of a system in the presence of uncertainty. This method is based on simulating the system many times to determine the variation in behaviour it can exhibit. SYVAC3 specializes in systems representing the transport of contaminants, and has several features to simplify the modelling of such systems. It provides a general tool for estimating environmental impacts from the dispersal of contaminants. This report describes the use and structure of SYVAC3. It is intended for modellers, programmers, operators and reviewers who deal with simulation codes based on SYVAC3. From this manual they can learn how to link a model with SYVAC3, how to set up an input file, and how to extract results from output files. The manual lists the subroutines of SYVAC3 that are available for use by models, and ...

2000-07-01

302

Results of in-house cone-cup testing of low to high temperature SPF-alloys  

Energy Technology Data Exchange (ETDEWEB)

Material testing of SPF-sheet is usually done with coupon hot tensile testing. The optimum range of strain rates is determined with stepped strain tests. To overcome the problem of very few available testing facilities and time consuming and costly procedure, cone cup testing has been developed since long. This test can be generated directly in the workshop, no machining of samples is necessary and it is very much related to the real SPF-process. The analysis of suitable temperature and strain rate is done by simple measurement of resulting cone height. This paper describes a unique and novel variant of the above mentioned baseline design. It provides on-line data of the actual status of the cone cup forming resulting from the applied, constant pressure. Strain rate variations as a result from texture or from the alloy-related behaviour is detectable. Thinning and ''hardening'' behaviour of different alloys ...

2004-07-01

303

Relaxor or classical ferroelectric behaviour in ceramics with composition Ba{sub 1-x}Na{sub x}Ti{sub 1-x}Nb{sub x}O{sub 3}  

Energy Technology Data Exchange (ETDEWEB)

Ceramics with composition Ba{sub 1-x}Na{sub x}Ti{sub 1-x}Nb{sub x}O{sub 3} are of either classical ferroelectric (for 0{<=}x<0.075) and ferro- or antiferroelectric (for 0.55<x{<=}1) or relaxor ferroelectric type (for 0.075{<=}x{<=}0.55), the transition at T{sub c} being only diffuse without any frequency dispersion for this last region. All the corresponding dielectric characteristics, i.e. diffusivity of the ferroelectric-paraelectric transition, frequency dispersion of {epsilon}{sub r}', shift of T{sub m} with frequency deviation from the Curie-Weiss law, are determined. The relaxor behaviour is more relaxor the more the composition deviates from BaTiO{sub 3} and NaNbO{sub 3}. This study is in the field of preparation of relaxor ceramics free from lead in the interest of the environment, which present a transition temperature close to room temperature. (author)

2000-07-10

304

Relaxation and corrosion resistance of alloy 800 used for steam generator tubes of ship borne boilers  

Energy Technology Data Exchange (ETDEWEB)

The INCO ``INCOLOY 800`` trademark groups the Fe-Cr-Ni alloys containing 30 to 35% nickel, 19 to 23% chromium, 0,15 to 0,60% aluminium, 0,15 to 0,60% titanium and less than 0,10% carbon contents, used as construction materials for condenser and heat exchanger tubes. In parallel with water chemistry control and studies aimed at reducing the residual stresses resulting from tube expansion, studies have been conducted to a better understanding of this alloy, its metallurgy and its corrosion behaviour under accurately defined fabrication and heat treatment conditions. The purpose of this paper is to present the results of a behaviour study of INDRET alloy 800 concerning isothermal relaxation and effects of the said relaxation heat treatments on alloy microstructure studied with a transmission electron-chemical method to determine the sensitiveness to intergranular corrosion, and by electrochemistry in pressurized hot water. (authors). 4 figs., 5 ...

1994-12-31

305

Reinforcement analysis and design of mechanical roof bolting systems in horizontally bedded mine roofs  

Energy Technology Data Exchange (ETDEWEB)

In order to design roof bolting systems safely and economically, it is essential to understand the flexural behaviour of the immediate roof. Based on the strata sequence, the strata in the immediate roof are divided into three types. The flexural behaviour of the three strata types are investigated in terms of the following effects: roof span, horizontal stress, thickness and Young's modulus of the lowest strata. The suspension reinforcement mechanism is analysed using beam-column theory. The equations for the maximum bending stress, deflection and transferred bolt load for the bolted strata are derived. In the analysis, the bolt load is assumed to be a point load and a horizontal stress is uniformly applied to each stratum. The friction reinforcement mechanism is also investigated. The major function of roof bolting in this case is to create frictional resistance by tensioning the roof bolts so that the individual layers are combined ...

1985-05-01

306

Propagation of an alkaline wave with a short contact time through an argilite sample from the Meuse-Haute Marne underground laboratory; Propagation d'une onde alcaline a temps de contact court a travers un echantillon d'argilite de l'est  

Energy Technology Data Exchange (ETDEWEB)

In the framework of the feasibility study of radioactive waste disposal in deep geologic formations, a clay formation (named 'argilite de l'Est') has been selected in the Meuse-Haute Marne region (France) for the construction of an underground laboratory. The percolation of alkaline solutions through the argilite has been studied using column experiments with short residence times (30 min). These experiments simulate the leaching of a cement which could be used in the building materials of the laboratory. The alkaline solutions used are mono-cationic solutions of calcium, sodium and strontium. The behaviour of calcium is differentiated from the other cations. For all alkaline solutions (NaOH, Ca(OH){sub 2} or Sr(OH){sub 2}) chemical reactions consuming both hydroxide ions and their associated cations have been evidenced. These reactions are heterogenous reactions of surface adsorption by site ionization. The calcium has a different ...

2001-07-01

307

Predictions of nitrogen oxides production in diffusion turbulent flames; Predictions de la production des oxydes d`azote dans les flammes turbulentes de diffusion  

Energy Technology Data Exchange (ETDEWEB)

The suitability of the turbulent combustion flamelets model in order to predict the index of NO{sub x} production in turbulent flames of hydrogen diffusion is analyzed. In the flamelet approach, the turbulent flame is equivalent to a group of laminar flames submitted to a mechanical stretching which generates a chemical disequilibrium. This effect can be described by the stretching or by the scalar dissipation ratio. A numerical modeling is performed in order to evaluate the advantages of both approaches and to compare the behaviour of the NO{sub x} emission index with the experiments of Chen and Driscoll. This study shows that predictions of NO{sub x} emission indexes have a correct behaviour with respect to the Damkoehler number only when the scalar dissipation ratio is used as a parameter to describe the chemical state outside equilibrium. Predictions of the flamelet models are improving when the Damkoehler number increases. On the other ...

1996-12-31

308

Prediction of the lifetime behaviour for C/C-SiC tubes as high and ultrahigh temperature heat exchangers (HITHEX) - material characterisation and qualification  

Energy Technology Data Exchange (ETDEWEB)

Heat exchangers for high and ultrahigh temperatures are a need and a precondition to realise high efficient fossil fired power plants based on the so-called Externally Fired Combined Cycle (EFCC) or the Indirect Fired Gas Turbines (IFGT). The main target of both processes is to increase the thermal efficiency of existing power plants by approximately 25% resulting in the same decrease in fuel consumption and, therefore, in the same reduction of CO{sub 2} formation. The main activities of the MPA University of Stuttgart in this project is focused on the characterisation and qualification of the structural material of the ultrahigh temperature heat exchanger (UHTHE) necessary in the above mentioned processes. The influence of the temperature and load on the material behaviour have been analysed by means of tensile tests and creep tests. The effectiveness of different coating systems and the interaction between coating system and basic material was also investigated. ...

2004-07-01

309

Pozzolanic behaviour of compound-activated red mud-coal gangue mixture  

Energy Technology Data Exchange (ETDEWEB)

The pozzolanic behaviour of compound-activated red mud-coal gangue has been investigated through TG, DTA, XRD, FTIR and {sup 27}Al MAS NMR. From viewpoint of reaction kinetics, it is found that the pozzolanic reaction mechanism of the compound-activated red mud-coal gangue-lime system is clearly consistent with diffusion control up to 14 days, and the reaction rate constant calculated from Jander equation decreases with the increase of CaO addition in the system. The hydration products formed in the red mud coal gangue-lime systems at ambient temperature are essentially aluminous C-S-H and Ca{sub 3}Al{sub 2}O{sub 6} center dot xH{sub 2}O. From TG analysis results, it is thought that the high amount of Ca(OH){sub 2} in the pastes of studied system is not conducive to the continual increase of non-evaporable water content of the hydration products. Of particular interest. {sup 27}Al MAS NMR proved to be an effective technique to obtain valuable information of Al(4) ...

2011-03-15

310

Pozzolanic behaviour of compound-activated red mud-coal gangue mixture  

International Nuclear Information System (INIS)

The pozzolanic behaviour of compound-activated red mud-coal gangue has been investigated through TG, DTA, XRD, FTIR and 27Al MAS NMR. From viewpoint of reaction kinetics, it is found that the pozzolanic reaction mechanism of the compound-activated red mud-coal gangue - lime system is clearly consistent with diffusion control up to 14 days, and the reaction rate constant calculated from Jander equation decreases with the increase of CaO addition in the system. The hydration products formed in the red mud-coal gangue - lime systems at ambient temperature are essentially aluminous C-S-H and Ca3Al2O6.xH2O. From TG analysis results, it is thought that the high amount of Ca(OH)2 in the pastes of studied system is not conducive to the continual increase of non-evaporable water content of the hydration products. Of particular interest, 27Al MAS NMR proved to be an effective technique to obtain valuable information of Al[4] in C-S-H and Al[6] in Ca3Al2O6.xH2O.

2011-03-01

311

Numerical simulation of a 1200 MWth pulverised fuel oxy-firing furnace  

Energy Technology Data Exchange (ETDEWEB)

The Oxycoal burner for pulverised coal combustion previously developed by the authors has been scaled up to typical power plant dimensions and a CFD study of pulverised coal combustion in a 1200 MWth oxy-firing furnace has been performed. The study revealed the importance of modelling the flue gas radiation behaviour for flue gas temperatures and wall heat transfer. This was done using a non-grey implementation of the Exponential Wide Band Model (EWBM). Typically, comparisons between air and oxy-fired furnaces point out that to obtain similar flame behaviour, the oxygen content in oxy-firing conditions should be increased until the same adiabatic flame temperature is reached. However, it was found that for these conditions, significantly increased wall heat fluxes can be the result. Furthermore, at gas temperatures comparable to air combustion, particle burnout is accelerated in oxy-firing due to the influence of heterogeneous gasification ...

2009-07-01

312

Negotiated settlements with a cost of service backstop: The consequences for depreciation  

International Nuclear Information System (INIS)

The movement from traditional regulatory hearings to negotiated settlements represents both a departure from cost of service regulation and a relaxation of regulatory oversight. Under negotiation parties are able to renegotiate inclusions in their cost of service while simultaneously creating a profit margin for the regulated firm where none existed under the cost of service outcome of a traditional hearing. This paper constructs a model to illustrate the existence of positive gains to pipeline and shipper from the re-allocation of expenses through time in the regulated pipeline services market in Canada. Behaviour consistent with the model is observable in anecdotal and econometric evidence gathered from the library of the National Energy Board of Canada, responsible for pipeline toll regulation in Canada. Empirical investigation by into settlement procedures in the Florida electricity market reveals similar findings; however, this analysis represents the first ...

2011-03-01

313

Mechanism of ageing in irradiated polymers  

Energy Technology Data Exchange (ETDEWEB)

Samples of ultra-high molecular weight polyethylene (UHMWPE) and nylon 66, of grades suitable for use in medical prostheses, were subjected to irradiation using a /sup 60/Co source. The effects of a 10 Mrad dose on percentage crystallinity, tensile behaviour and dynamic mechanical response were established 3 days after irradiation at intervals over a one year period. Crystallinity in UHMWPE was found to increase progressively during this period with consequent changes in mechanical behaviour. It is proposed that the observed ageing process arises from the breakdown of metastable groups in the polymer, which are formed on irradiation, with consequent release of long inter-lamella tie chains. This removes an inhibition to crystal perfection processes, which can occur at room temperature in polyethylene. Infra-red spectroscopic evidence supports the proposal that the metastable species is peroxy or hydroperoxy and that this decomposes on ageing to ...

1988-01-01

314

Locomotive engineers and their spouses: coffee consumption, mood, and sleep reports.  

Science.gov (United States)

Locomotive engineers (train drivers) on irregular work schedules reported a general coffee consumption rate higher than that reported by a comparison sample of permanent shift factory workers. The present study examines the impact of this consumption on workday and non-workday sleep behaviour and mood ratings. Twenty-seven engineers and their spouses each completed daily logs for 30 consecutive days. Daily logs were then sorted into workday and non-workday categories. Workday sleep length was significantly shorter than non-workday sleep length for both engineers and spouses. For the engineers only, coffee consumption on workdays was higher than on non-workdays. This increased coffee consumption was correlated with longer sleep latency, increased negative mood, and decreased positive mood on both work and non-workdays. This was not true for spouses. These results may be related to a days-off carry-over effect of caffeine or a general consumption ...

315

Kondo effect and impurity-impurity interaction in (La, Ce)B_6 alloys  

International Nuclear Information System (INIS)

Measurements of the magnetic susceptibility betweeen 0.03 and 300 K and of the magnetization between 0.05 and 10 K for magnetic fields up to 60kOe have been used to investigate effects from the interaction between the conduction electrons and local magnetic moments in (Lasub(1-x)Cesub(x))B_6 alloys (0.0007<=x<=0.10). For Ce concentrations x<0.006 the data show Kondo-type single impurity behaviour at low temperatures with a transition from a magnetic to a non-magnetic regime of the Ce ions. In the magnetic regime the impurity susceptibility follows a Curie-Weiss law, and in the non-magnetic regime it varies with T"2. An external magnetic field gradually restores the free-ion behaviour of the Ce impurities. For more concentrated alloys interactions between the impurities are observed. The RKKY interaction strength derived is more than two orders of magnitude smaller than in the Kondo system CuFe. Values of the s-f exchange integral, J, ...

1978-01-01

316

Kinetics of the stress induced phase transition in quartz by real-time neutron scattering  

International Nuclear Information System (INIS)

Complete text of publication follows. The stability regime of the incommensurate phase of quartz is influenced by uniaxial stress. Hence, the phase transition can be induced under isothermal conditions by the application of external mechanical forces. Using real-time neutron scattering the time evolution of structural changes is investigated id detail during stress variations. The time dependent behaviour of the satellite reflection is compared with that one of the fundamental Bragg reflection which - via primary extinction - gives information about the perfection of the crystal. On increasing stress the perfection of the lattice is destroyed immediately while the modulated structure is built up with a delay of about 1 s. Decreasing the stress leads to a reverse behaviour. Moreover, there is evidence that under periodical load residual non-relaxed strain fields survive leading to a different temperature dependence as compared to static ...

1999-09-01

317

Interfacial reactions between PbO-rich glasses and aluminium composites  

CERN Document Server

565 deg C occurs when dissolution rate exceeds oxidation rate, exposing the fresh Al anode to the glass melt. Under inert atmosphere (at 583 deg C), air oxidation is not possible and galvanic cell redox reactions generate an excessive copper interlayer as the system attempts to sustain the oxide layer at the anode. Similar behaviour is observed in those coatings formed on the alloy using glass C (containing Al sub 2 O sub 3 and Na sub 2 O). In this case, the interfacial reactions involve the PbO of the glass and Pb-rich spherical precipitates are formed in the interfacial region, along side sodium aluminosilicate phases, precipitated from the PbO-depleted glass. The behaviour in both systems indicates that oxygen diffuses through the edge of the glass drop, from the atmosphere, to the substrate/glass interface. Coatings formed on the MMCs in air exhibited a porosity of approx 10%, attributed to the production of CO sub 2 gas through the ...

2000-01-01

318

Institutt for Energiteknikk - Annual Report 1994  

Energy Technology Data Exchange (ETDEWEB)

Work at Institutt for energiteknikk (IFE) comprises both nuclear and non-nuclear activities. The main nuclear program is centered on the Halden Reactor Project. In 1958, the first Halden Reactor Project Agreement was signed by organisations representing 12 European countries. During 1994 France became a full member and associate membership was established with Russia. Accordingly, 16 countries were participating in the Project by the end of the year. The objectives have evolved from being simply a demonstration of the operation of a boiling heavy-water reactor to becoming a substantial research and development programme covering the domains of human-machine interaction, fuel behaviour, materials testing, water chemistry, and instrumentation. In 1994, significant progress was achieved in all of the areas addressed by the project, including the re-instrumentation of irradiated fuel rods, fission gas release, irradiation-assisted stress corrosion cracking, a ...

1995-12-01

319

Influence of the Alfven wave spectrum on the scrape-off layer of the TCA tokamak  

International Nuclear Information System (INIS)

The study of the scrape-off layer (SOL) during Alfven wave heating may lead to a better understanding of the antenna-plasma interaction. The scrape-off layer of the TCA tokamak has been widely investigated by means of Langmuir probes. The aim of this work is to present measurements on the influence of the Alfven wave spectrum on the scrape-off layer. These experiments have shown that the plasma boundary layer is strongly affected by the wave field, in particular the ion saturation current and the floating potential. In TCA, as the spectrum evolves due to a density rise, the passage of the Alfven continua and their associated eigenmodes, the Discrete Alfven Wave (DAW) induces a strong depletion in the edge density of up to 70% during the continuum part and a density increase during the crossing of an eigenmode. The floating potential becomes negative during the continua and even more negative crossing the eigenmodes. In case of MHD mode activity, this behaviour ...

1988-05-01

320

High temperature susceptibilities of actinide monopnictides and monochalcogenides  

International Nuclear Information System (INIS)

The inverse susceptibilities of the monopnictides and monochalcogenides of the light rare earths plotted vs. temperature flatten off at high temperatures. This behaviour is well explained by van Vleck paramagnetism of the excited states of the multiplet. For almost all actinide pnictides and chalcogenides a similar flattening-off is observed. Since spin orbit coupling is much stronger than in the light rare earth compounds an analogous interpretation is not possible. Susceptibility curves for uranium compounds can be fitted by adding a temperature dependent enhanced Pauli paramagnetism to the Curie-Weiss term (modified Curie-Weiss law). The high temperature susceptibility behaviour of neptunium compounds is very similar to uranium compounds i.e. an appreciable deviation from the Curie-Weiss law is only visible for the chalcogenides. The plutonium chalcogenides show a temperature independent paramagnetism, which can be explained either by a ...

1998-06-12

321

Hemoglobin radiolabeling: in vitro and in vivo comparison of iodine labeling with iodogen and a new method for technetium labeling  

International Nuclear Information System (INIS)

The present investigation compares the suitability of two radiolabeling techniques for hemoglobin. "1"2"5I labeling of hemoglobin with Iodogen as iodinating agent caused major changes in the chromatographic behaviour and an accelerated plasma clearance of the labeled hemoglobin in rats. A recently developed two-step procedure for "9"9"mTc labeling gave better results. The label had only minimal influence on the chromatographic behaviour of hemoglobin. In vivo, no free label occurred in the circulation and no transfer of the label to other plasma proteins took place. The plasma clearance of "9"9"mTc-labeled hemoglobin in rats was slowed. However, this could be explained entirely by diminishing glomerular filtration, probably by inhibition of the dissociation of the hemoglobin molecule into dimers. The plasma clearance of hemoglobin modified by intramolecular cross-linking, which prevents dissociation of the molecule into dimers and thus ...

322

Flow behaviour and microstructure of the heat-resistant steels X20CrMoV12.1 and X5NiCrTiAl32.20 (alloy 800)  

Energy Technology Data Exchange (ETDEWEB)

Flow-curve characteristics of the heat-resistant steels X 20 CrMoV 12.1 and alloy 800 (X5NiCrTiAl32.20) were measured by tensile and compression tests at temperatures between room temperature and 800 C and strain rates {epsilon}{<=}10 s{sup -1} in connection with microstructure investigations (dislocation content, carbide precipitation) by TEM and X-ray diffraction analysis (XDA). Modelling the deformation behaviour of the steels in terms of the microstructure development indicates that it cannot be explained in a simple manner. The flow curves {sigma}={sigma}({epsilon}, {epsilon}, T) lie, in general, between those predicted by the Kocks-Mecking-Estrin model and a modified (i.e. two-parameter) Roberts model. Because of the less complicated nature of the deformation process the correspondence of experiment and modelling is more satisfying in the case of the material X 20 CrMoV 12.1. (orig.) 26 refs.

1999-10-01

323

Finite element model selection using Particle Swarm Optimization  

CERN Document Server

This paper proposes the application of particle swarm optimization (PSO) to the problem of finite element model (FEM) selection. This problem arises when a choice of the best model for a system has to be made from set of competing models, each developed a priori from engineering judgment. PSO is a population-based stochastic search algorithm inspired by the behaviour of biological entities in nature when they are foraging for resources. Each potentially correct model is represented as a particle that exhibits both individualistic and group behaviour. Each particle moves within the model search space looking for the best solution by updating the parameters values that define it. The most important step in the particle swarm algorithm is the method of representing models which should take into account the number, location and variables of parameters to be updated. One example structural system is used to show the applicability of PSO in finding ...

2009-01-01

324

Fatigue and creep crack growth behaviour at high temperatures for weld metals of Alloy 800 and Alloy 617  

International Nuclear Information System (INIS)

High temperature fatigue crack growth (FCG) and creep crack growth (CCG) experiments have been conducted in air on weld metal, heat affected zone (HAZ) and base metal of the austenitic Alloy 800 and the nickel base Alloy 617. Tests were performed on specimens machined from pipes, in the temperature range 550-900 deg. C. The crack propagation mode was examined. At all temperatures and for both materials, FCG of base metal was found to be the highest, whereas the weld metal exhibited the lowest FCG rate. The FCG rate in the HAZ was found to lie in between of those observed for base and weld metal. The crack propagation mode remained transgranular in base metal and transdendritic in weld metal at all temperatures. CCG behaviour could be described using the energy rate integral C*. Base metal and weld metal exhibited similar CCG rate at same C*. The crack propagation mode under CCG condition was found to be intergranular in base metal and HAZ and interdendritic in the ...

1993-08-15

325

Experimental validation of upgraded designs for PERMCAT reactors considering mechanical behaviour of Pd/Ag membranes under H{sub 2} atmosphere  

Energy Technology Data Exchange (ETDEWEB)

The PERMCAT process chosen for the final clean-up stage of the Tokamak Exhaust Processing system of the ITER tritium plant combines in a single component a catalytic reactor and a permeator using Pd/Ag membranes. This study covers the mechanical behaviour of a Pd/Ag membrane under different operating conditions. The consequences of hydrogen uptake by the membrane during nominal operation but also during off-normal events are presented. Depending on the operating conditions, expansions around 2% and significant deformations are observed. Different mechanical designs of PERMCAT reactors are then discussed. The first generation comprises finger-type membranes and two new mechanical designs use either additional edge welded bellows or a special corrugated Pd/Ag membrane. These upgraded designs improve the robustness and simplify the geometry of the component. The experimental validation of these new units has been carried out based on the measurements of the processing ...

2007-10-15

326

Experimental validation of upgraded designs for PERMCAT reactors considering mechanical behaviour of Pd/Ag membranes under H_2 atmosphere  

International Nuclear Information System (INIS)

The PERMCAT process chosen for the final clean-up stage of the Tokamak Exhaust Processing system of the ITER tritium plant combines in a single component a catalytic reactor and a permeator using Pd/Ag membranes. This study covers the mechanical behaviour of a Pd/Ag membrane under different operating conditions. The consequences of hydrogen uptake by the membrane during nominal operation but also during off-normal events are presented. Depending on the operating conditions, expansions around 2% and significant deformations are observed. Different mechanical designs of PERMCAT reactors are then discussed. The first generation comprises finger-type membranes and two new mechanical designs use either additional edge welded bellows or a special corrugated Pd/Ag membrane. These upgraded designs improve the robustness and simplify the geometry of the component. The experimental validation of these new units has been carried out based on the measurements of the processing ...

2007-10-01

327

Enzymatic mechanism in low chloride media: influence of glucose oxidase on the electrochemical behaviour of AISI 316L stainless steel; Mecanisme enzymatique en milieux faiblement chlorures: influence de la glucose oxydase sur le comportement electrochimique de l'acier inoxydable AISI 316L  

Energy Technology Data Exchange (ETDEWEB)

The open circuit potential (OCP) of stainless steels immersed in natural waters generally increases with time. This phenomenon is strongly linked to the formation of a bio-film on the surface. Several studies have proved that the bio-film modifies the reaction of reduction of dissolved oxygen and that it acts mainly on the cathodic processes. One of the hypotheses explaining the action of the bio-film involves certain bacteria which use dissolved oxygen and extracellular enzymes to produce reactive oxygen species. Among this kind of metabolites is hydrogen peroxide H{sub 2}O{sub 2}. This compound interacts with the passive layer of stainless steels and affects their electrochemical behaviour, even when the chloride concentration is low. The aim of this work is to study the influence of an enzymatic reaction (of the oxidoreductase type) on anodic and cathodic processes on AISI 316L stainless steel. Experiments are carried out in two artificial electrolytes ...

2006-07-01

328

Comparative study of the electrochemical behaviour of iron in alkaline media containing red mud and grey slurries. the effect of Al{sup 3}+; Estudio comparativo del comportamiento electroquimico del hierro en medio alcalino en presencia de lodos rojos y lodos grises. Efecto del Al{sup 3}+  

Energy Technology Data Exchange (ETDEWEB)

Red mud (Rm) is the main by-product of the Bayer process for alumina extraction from bauxite, and grey slurries (GS) are generated during the granite rocks transformation processes. the huge volume of those wastes generated every year suppose a serious environmental problem. Recent works by our group demonstrate the efficiency of both types of muds as corrosion inhibitors for iron and steel in alkaline media containing chlorides. The elemental analysis of these slurried shows that Al{sup 3}+ is the main common element. Therefore, the aim of this paper is to study the effect of the soluble Al{sup 3}+ in the electrochemical behaviour of iron in alkaline media, in presence and absence of chlorides. The electrochemical study using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) together with surface analysis techniques allowed to conclude that Al{sup 3}+ blocks the surface of steel in alkaline media chloride increasing the steel resistance to ...

2009-07-01

329

Capacitive behaviour and electronic structure of passive films formed on nickel base alloy type Inconel 600; influence of Cr and Fe. Comportement capacitif et structure electronique des films passifs formes sur l'alliage a base de nickel du type Inconel 600 (75Ni-16Cr-8Fe); influence du chrome et du fer  

Energy Technology Data Exchange (ETDEWEB)

The study of passive films formed on a nickel base alloy type Inconel 600 is performed by capacitance measurements (Mott-Schottky approach). This research is supported by the passivation study of the alloying elements Ni, Cr, Fe and high purity alloys Ni-Cr, Ni-Fe, Ni-Cr-Fe. The results obtained show that the capacitive behaviour of the Inconel 600 in the passive state is similar to that on a p-n heterojunction to which a barrier zone of nickel oxide is added. The individual or combined action of alloying elements on the development of this kind of electronic structure is discussed. (authors). 5 refs., 6 figs.

1994-08-01

330

CATHENA simulation of the WOLSUNG D_20 spill incident of 1984 November 25  

International Nuclear Information System (INIS)

The CATHENA (formerly ATHENA) has been used to simulate the thermalhydraulic behaviour of the WOLSUNG-1 CANDU-600 reactor during the D_20 spill incident of 1984 November 25. A 4-inch (nominal) Liquid Relief Valve inadvertently opened in the reactor auxiliary system during normal reactor operation, resulting in a discharge of heavy water from the primary heat transport system. The valve remained open for approximately 29 minutes. CATHENA is an advanced thermalhydraulic computer code for analysis of postulated loss-of-coolant accidents (LOCA) and transient faults in CANDU nuclear reactors. A full two-fluid (six-equation) representation of the two-phase flow is used. Component models are used to represent pumps, valves, critical discharge, etc., which are necessary to describe the behaviour of the CANDU system under upset conditions. Heat transfer between the fluid and piping walls (or fuel) is modelled using applicable correlations for boiling, ...

1986-06-09

331

Behavioural evidence for mental time travel in nonhuman animals.  

Science.gov (United States)

If episodic memory is an adaptation, it must have evolved to benefit present or future survival and reproduction, rather than to provide an accurate record of the past per se. Recent research has documented various links between the ability to construct episodes of the past and imagine potential future episodes, and it has been argued that the former may be a design feature of the latter. Thus, claims about the existence of episodic memory in non-verbal organisms may be evaluated by examining behavioural evidence for foresight. Here we review recent data on foresight in animals and conclude that the evidence to suggest episodic memory so far is equivocal. We suggest specific experimental criteria that could provide stronger evidence. We maintain that there must be uniquely human traits for which there are no animal models and it remains possible that mental time travel depends on several such traits. Identification of what precisely is unique about the human ...

2009-12-03

332

Behaviour of the de-inked tailings soil cover at the Clinton mining site; Comportement de la couverture de residus de desencrage au site minier Clinton  

Energy Technology Data Exchange (ETDEWEB)

The production of de-inked tailings in Quebec has significantly increased during the last decade. From less than 100,000 wet tons in 1990, the production of de-inked tailings reached 500,000 wet tons in 1995, and 510,000 wet tons in 1999. The geotechnical, hydraulic, and physico-chemical properties of de-inked tailings are favorable for its use as soil cover for the prevention of acid mine drainage at mining sites. In this presentation, the authors discussed the three-year monitoring of the behaviour of a membrane covering an old mining site with the potential to produce acid mine drainage. The site is located at the Clinton Mine, near Woburn, Quebec. The mine shaft was filled with the tailings and waste rock scattered around the site and covered with a protective membrane which included de-inked tailings. The profile of the membrane was discussed, as well as construction details. The results confirmed the good performance of the soil cover in the prevention of ...

2000-07-01

333

Behaviour of nonlinear supports on a PWR coolant system during a postulated LOCA. Pt. 1; Effect of modelling methods  

Energy Technology Data Exchange (ETDEWEB)

A 4-loop Pressurised Water Reactor (PWR) primary coolant system has been analysed for the postulated Loss of Coolant Accident (LOCA) event in order to derive peak dynamic loads for qualifying the design of equipment supports and pipe whip restraints. Pipe whip restraints as well as pipe and equipment supports are nonlinear by nature because of the presence of gaps and the different directional stiffnesses arising from snubber, steelwork and geometric and material interaction at the concrete to steel embedment. The different structural idealisations for the supports and restraints have an influence on the dynamic response of the structure. In the first of the two part paper a range of idealisation models for the Steam Generator and Reactor Coolant Pump vertical columns ranging from elastic stiffnesses to bilinear stiffnesses with or without preload were examined. Due to both structural and loading complexity, the behaviour of these supports were analysed by the ...

1993-07-01

334

Anodic behaviour of Al-refractory metal amorphous alloys  

Energy Technology Data Exchange (ETDEWEB)

In order to understand the anodic behaviour of Al--Mo and Al--W amorphous alloys in the borate buffer electrolyte, samples of these alloys were polarized galvanostatically. The resultant anodic films were thicker than the passive films formed during potentiodynamic polarization enabling detailed examination of the films and alloy substrates by surface analytical methods. AES investigations suggest that the anodic films formed at low and moderate voltages on Al--Mo or Al--W amorphous alloys consist of Al-oxide, whereas refractory metals remain unoxidized and enriched at the film/substrate interface. Molybdenum and tungsten act as 'dissolution moderators', restraining the substrate dissolution process at the film/substrate interface. However, after anodization at high voltages (50 V), AES revealed the presence of an oxidized refractory metal in the inner part of the anodic film. Based on these results of growth of thick anodic films, the role of Mo ...

1999-07-31

335

Adsorption behaviour of some actinide and lanthanide elements on pyridine-type anion exchange resin from hydrochloric acid solution  

Energy Technology Data Exchange (ETDEWEB)

One option in establishing advanced technology for disposing of high-level radioactive waste (HLW) is to remove TRU elements from HLW and then transform them into short-lived radionuclides. Tertiary pyridine-type anion exchange resin was investigated as a separation medium for spent fuel reprocessing using a HCl solution. Distribution coefficients of typical elements, along with uranium, were measured in the pyridine resin--HCl solution system, where HCl concentration was varied from 1 to 9 M. The results reveal: elements of the alkali metal, alkaline earth and lanthanide groups are not adsorbed, the adsorption patterns of the transition metals differ according to HCl concentration, and uranium is adsorbed in the high HCl concentration region. Furthermore, the present report describes the experimental results obtained for the adsorption behaviour of uranium, americium, curium and various lanthanide elements on tertiary pyridine-type anion exchange resin from ...

1999-08-01

336

A novel photodiode made of hybrid organic/inorganic nanocomposite  

International Nuclear Information System (INIS)

Novel hybrid organic/inorganic nanocomposites made of metal oxide and conjugated polymer nanocomposite and its application in bulk-heterojunction solar cells were studied. The composite was composed of different concentrations of strontium titanate (SrTiO_3) and polyaniline doped phosphoric acid. The optimum concentration of strontium titanate was found to be 0.2 v/v. An inorganic-organic photovoltaic device with a structure of Ag/Pani-H_3PO_4-SrTiO_3/Al has been fabricated. The ideality factor value of the diode was found to be 1.8. This n value of the diode implies a deviation from ideal junction behaviour. The barrier height #phi#_b value for the diode was found to be 0.56 eV. The Ag/Pani-H_3PO_4-SrTiO_3/Al diode shows a photovoltaic behaviour with a maximum open-circuit voltage V_o_c of 2.49 V, and short-circuit current I_s_c of 5.6 mA under light illumination #lambda# = 460 nm. The conversion efficiency was found to be 5.2%. It is ...

2009-08-07

337

[The simulation of 137Cs distribution in forest ecosystems and prediction of its accumulation by forest products].  

Science.gov (United States)

A mathematical model of 137Cs migration in forest ecosystem is presented, which describes the behaviour of this radionuclide in the forest litter-soil system, trees, understory and forest animals. The model's parameters for different types of forest ecosystems are estimated and model's adequacy is tested through the use of independent experimental data. The sensitivity of the model's output variables is analyzed to variations in the most significant parameters. The differences in the seasonal and mean annual dynamics of 137Cs concentration in muscles of roe deers and mooses are shown to be defined by specific features of the diets of these animals and variations in 137Cs content in the main diet components. PMID:11402557

338

Wilson loops in warped resolved deformed conifolds  

CERN Document Server

We calculate quark-antiquark potentials using the relationship between the expectation value of the Wilson loop and the action of a probe string in the string dual. We review and categorize the possible forms of the dependence of the energy on the separation between the quarks. In particular, we examine the possibility of there being a minimum separation for probe strings which do not penetrate close to the origin of the bulk space, and derive a condition which determines whether this is the case. We then apply these considerations to the flavoured resolved deformed conifold background of Gaillard et al. We suggest that the unusual behaviour we observe in this solution is likely to be related to the IR singularity which is not present in the unflavoured case.

2011-01-01

339

Ventilation by the windows in classrooms: a case study  

Energy Technology Data Exchange (ETDEWEB)

Four classrooms of two secondary schools located around Lyon in France have been monitored. The objectives are to analyse the quality of the indoor air and the thermal comfort and also the behaviour of the occupants towards opening of the windows. This paper briefly describes the context and the nature of the monitoring campaign, and presents the results of the measurements with direct interpretation of the ventilation needs. Results from this study show that allowable CO{sub 2} levels are overpassed several times in a school day. The presence of a mechanical ventilation system leads to lower peaks but the fresh airflow is too small to prevent an indoor confining, that is also revealed by the aerobiological analysis. (author)

1994-12-31

340

Use of stable isotopes in developing countries: safe markers for nutrition regime study  

International Nuclear Information System (INIS)

Possible use of stable radioisotopes in studies on nutrition and medicine problems that may be used in investigations of babies, children, pregnant women is shown. Attention is paid to behaviour of limited number of elements: hydrogen, carbon, nitrogen, oxygen. The IAEA plans implementation of a new coordinated research program on use of stable isotopes for studying nutrition problems and related diseases. The program emphasis will be placed on protein metabolism measurements and estimation of energy consumption in control population groups in developing countries.

341

Thermal properties of UPdSn and UCuSn  

International Nuclear Information System (INIS)

We report on the specific heat and the thermopower of UPdSn and UCuSn, both of which order antiferromagnetically at low temperatures. The compounds show similar behaviour in the specific heat, and the large magnetic-entropy changes around T_N are evidence for a large degree of 5f-electron localization. For both compounds, we find that thermopower results are consistent with the findings for the electrical resistance. While for UCuSn very abrupt changes at 25 and 60 K are observed for both quantities, more continuous changes at the magnetic transitions (25 and 40 K) are found for UPdSn. (orig.).

1996-09-24

342

Theoretical approach on microscopic bases of stochastic functional self-organization: quantitative measures of the organizational degree of the environment  

International Nuclear Information System (INIS)

There has been increased theoretical and experimental research interest in autonomous mobile robots exhibiting cooperative behaviour. This paper provides consistent quantitative measures of organizational degree of a two-dimensional environment. We proved, by the way of numerical simulations, that the theoretically derived values of the feature are reliable measures of aggregation degree. The slope of the feature's dependence on memory radius leads to an optimization criterion for stochastic functional self-organization. We also described the intellectual heritages that have guided our research, as well as possible future developments. (author)

2001-11-30

343

The use of water-soluble hydrazones as inhibitors for the corrosion of C-steel in acidic medium  

Energy Technology Data Exchange (ETDEWEB)

Inhibition efficiency of some water-soluble hydrazones for C-steel corrosion in hydrochloric acid has been tested by weight loss, polarisation measurements and open circuit technique. The inhibition effect was attributed to the adsorption of the additives on the C-steel surface as supported by adsorption measurements at Pt electrode using cyclic voltammetry. Electrochemical measurements indicated that all the additives behave as cathodic-type inhibitors. The data obtained fit well to both the Temkin adsorption isotherm and the kinetic-thermodynamic model. The inhibition behaviour and its order were explained with the help of the proposed skeletal representation.

2007-09-15

344

The properties and transport phenomena in oxide films on iron, nickel, chromium and their alloys in aqueous environments  

International Nuclear Information System (INIS)

The construction materials used in coolant systems in nuclear power plants become covered with oxide films as a result of exposure to the aqueous environment. The susceptibility of the materials to different forms of corrosion, as well as the extent of the incorporation of radioactive species on the surfaces of the primary circuit, are greatly influenced by the physical and chemical properties of these oxide films. The composition and characteristics of the oxide films in turn depend on the applied water chemistry. This work was undertaken in order to collect and evaluate the present views on the structure and behaviour of oxide films formed on iron- and nickel-based materials in aqueous environments. This survey should serve to recognise the areas in which more understanding and research effort is needed. The review begins with a discussion on the bulk oxides of iron, nickel and chromium, as well as their mixed oxides. In addition to bulk oxides, the structure and ...

2010-03-01

345

The newborn infant: a missing stage in developmental psychology  

British Library Electronic Table of Contents (United Kingdom)

Abstract Although neonatology, the study of the newborn, is well established in medical science, psychological research on the newborn is relatively scarce. Can we justify this period as a distinct stage of human development in Psychology? This introductory article considers the unique characteristics of the neonatal period, the impact of the transition to extrauterine life, including the impact of birth itself, and the stages of brain development that characterize this period. It presents evidence of an intentional, intersubjective neonate, and uses behavioural and neuroscientific evidence to argue that the neonate's early social preferences and responses indicate a unique, sensitive, experience-expectant stage of development. The authors of this issue agree in proposing that the newborn ...

2011-01-01

346

The evolution of rigid-plastic dynamic response by mathematical programming  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a systematic approach to the automatic determination of the evolution of the rigid-plastic structural response caused by a proportional or single parameter pressure loading which varies with time in a monotonic non decreasing fashion. The frame structure is envisaged as a network, and the fundamental vectorial conditions characterising its behaviour at any instant of time are combined in a consistent manner. By considering the level of the pressure loading to be a single load parameter ranging monotonically from zero to infinity, the structural governing system may be regarded as a parametric linear complementary problem. (author). 13 refs., 2 figs.

1995-12-31

347

The anisotropy of the Curie-Weiss law in dysprosium  

International Nuclear Information System (INIS)

In the paramagnetic region T > 178 K the paramagnetic susceptibility, chi, of Dy was measured as a function of temperature and orientation of the applied magnetic field with respect to the c-axis. For magnetic fields parallel and perpendicular to the c-axis the temperature dependence of chi can be represented by Curie-Weiss laws whereas for arbitrary orientations significant deviations from a Curie-Weiss behaviour were found. The measured anisotropy of the paramagnetic Curie temperatures and of the Curie-Weiss constants is shown to depend mainly on the magnetocrystalline energy and an anisotropic g-factor. (Auth.).

1979-10-01

348

THE DEVIL AND CUSTOMER RELATIONSHIP MANAGEMENT  

British Library Electronic Table of Contents (United Kingdom)

The paper takes as its starting point the diffusion of ICT applications associated with so-called 'customer relationship management' (CRM). CRM encourages organisations to shift their understanding of customers from an episodic and transaction-based perspective to one that emphasises continuous 'relationship management'. CRM applications thus promise to deliver more, real-time accurate information about consumer habits and behaviours therefore allowing organisations to maximise their extraction of business value. This paper explores the ways in which such inscriptive technologies are not merely referential but also constitutive of contemporary re-presentations and ideals of the consuming subject. Focusing on what we might call the 'digital doubles' of customer relationship management the a...

2010-01-01

349

Synthesis of histidine-stabilized cadmium sulfide quantum dots: Study of their fluorescence behaviour in the presence of adenine and guanine  

British Library Electronic Table of Contents (United Kingdom)

Cadmium sulfide particles have been synthesized in the aqueous medium using the amino acid histidine as a stabilizing agent. These particles demonstrate the phenomenon of size quantization effect. The fluorescence of histidine-stabilized CdS was found to be enhanced and quenched by the addition of DNA bases adenine and guanine, respectively. The fluorescence enhancement of CdS in the presence of adenine has been explained on the basis of interaction between the quantum dot stabilizer and the amino group of adenine. Quenching of CdS fluorescence by guanine occurs due to interaction of the substrate with the quantum dot surface.

2010-01-01

350

Superplastic behaviour in Ti-3Al-4V  

International Nuclear Information System (INIS)

Superplastic deformation behavior in an alpha + beta titanium alloy Ti-3A-4V has been investigated by using the method of cross head speed cycling in the temperature range 750-910 /sup 0/C. On the basis of flow stress-strain rate-strain rate sensitivity data, the alloy was found to be superplastic in the entire temperature range studied. Optimum superplasticity was observed in the strain-rate range 3 x 10/sup -5/ sec./sup -1/ to 6 x 10/sup -5/ and at the highest temperature of 910 deg. C. (author).

351

Study of the influence of surface carbon on the tribological properties of ion-treated steels  

Energy Technology Data Exchange (ETDEWEB)

Samples of 100Cr6 steel were treated by different ion beams in order to study the evolution of their tribological properties. A strong correlation was found between the amount of surface carbon, whatever its origin (contamination, direct C implantation or ion-beam mixing of a deposited carbon layer), and the reduction of the friction coefficient as well as the improvement of the wear resistance. These results are discussed in the framework of a recent statistical model founded on the asperity concept and describing the tribological behaviour of bilayer systems.

1999-01-02

352

Spectrometric techniques application to study of environmental contamination levels in south Shetland Antarctic  

International Nuclear Information System (INIS)

The methodology for studying the behaviour of the toxic pollutant metals (Hg, Pb, Cd, Cr) in the South Shetland region is presented here, toxic pollutants are caused by the urban and industrial activity at the Southern hemisphere and they are pressured to be incorporated to the region though atmospheric transport processes the Cs 137 (refI) was used as a tracing element, which was freed and dispersed in the atmosphere as a result of nuclear bombs testing. During the austral summer samples from ground, sediments, atmospheric and glacier were extracted.

353

Some reflections on the network power plant interaction  

International Nuclear Information System (INIS)

The layout of the network with its frequency and transmission power control shows how the time behaviour of power plants and consumers determines the frequency curve during sudden power disturbances. As for switching processes in the network for the turbine, network operation entails loads due to shock-like disturbance functions to which one should not normally respond by switching off. The interception controllers are therefore adjusted via a simulation model by which the vibrations of the turbine rotor can be modelled in real time under different network loads. (GL).

1978-11-24

354

Recycling of PTFE by means of ionizing rays  

International Nuclear Information System (INIS)

By treatment with beta or gamma rays, PTFE waste is converted to high-grade PTFE fine powder. High-molecular weight PTFE is degraded to low-molecular weight PTFE. Due to this the density, the degree of crystallinity, and the melt flow index are increased, which enhances the brittleness of the material. Irradiation of PTFE thus facilitates milling and makes the material pourable and free-flowing. Milled PTFE fine powder, lie PTFE plastic, combines temperature resistance, weather fastness, and chemical stability with good slip behaviour and antiadhesive properties. Areas of application for fine powder include additives for plastics, printing inks, nonstick coatings, and antifriction lacquers. (orig.).

1994-01-01

355

Reciprocal regulation of the neural and innate immune systems  

British Library Electronic Table of Contents (United Kingdom)

Innate immune responses are regulated by microorganisms and cell death, as well as by a third class of stress signal from the nervous and endocrine systems. The innate immune system also feeds back, through the production of cytokines, to regulate the function of the central nervous system (CNS), and this has effects on behaviour. These signals provide an extrinsic regulatory circuit that links physiological, social and environmental conditions, as perceived by the CNS, with transcriptional 'decision-making' in leukocytes. CNS-mediated regulation of innate immune responses optimizes total organism fitness and provides new opportunities for therapeutic control of chronic infectious, inflammatory and neuropsychiatric diseases.

2011-01-01

356

Protective oxides in coal-fired combined cycle power systems  

Energy Technology Data Exchange (ETDEWEB)

In most industrial processes operating at elevated temperatures, protective oxide layers perform a vital duty in protecting the underlying metallic alloys from process gases. Coal-fired combined cycle power generation systems present a number of process conditions in which the properties of the protective oxide layers are particularly important. This paper discusses two of these particular conditions: (1) `erosion/corrosion` of in-bed heat exchanger tubing and (2) thermal cycling of hot gas path components. For both these situations, the desirable properties of protective scales are outlined. The behaviour of scales in practice are highlighted. 33 refs., 6 figs., 2 tabs.

1995-12-31

357

Prospective cognition in animals.  

Science.gov (United States)

The debate about whether or not animals have foresight has focused on whether animals can be shown to have episodic future thinking, that is the ability to travel mentally in time and see themselves in the future. This focus has distracted from consideration of other forms of foresight that animals demonstrate. We propose a framework for examining future-oriented behaviours and then discuss the evidence for future thinking in animals. In the final section we examine some perspectives of future thinking and suggest that there are future-oriented capabilities of animals that do not involve mental time travel but may yet involve future thinking which deserve further investigation. PMID:20522320

2009-03-01

358

Pitting corrosion of nickel base alloys in halide media  

International Nuclear Information System (INIS)

A computerized corrosion measuring system (EG and G model 350 A) was used to study the influence of Cr, Mo, Ti, Nb and W on the pitting corrosion of nickel base alloys in 3% NaCl at 90"0C. The electrochemical parameters under investigation are the corrosion potential E_c_o_r_r, pitting potential E_p and protection potential E_p_p. The corrosion behaviour of nickel base alloys were studied by using pitting scan and potentiostatic techniques. Values of corrosion potential, pitting potential and protection potential were used for a ranking of alloys for corrosion resistance.

1988-03-06

359

Passive dosimetry of radon and its daughters using solid state nuclear track detectors (SSNTDs)  

Energy Technology Data Exchange (ETDEWEB)

Indoor radon is a potential health hazard for the general public, especially in buildings with poor ventilation. A variety of dosemeters have been developed and used in surveys of radon concentration measurements. In this article the passive dosemeters which are based on solid state nuclear track detectors are reviewed. The principle of passive dosimetry and the factors affecting their performance are discussed. The characteristics of SSNTD materials in relation to their behaviour under different environmental conditions are tabulated and discussed. Results of radon surveys from selected studies are also presented. (Author).

1993-01-01

360

On Financial Markets Based on Telegraph Processes  

CERN Document Server

The paper develops a new class of financial market models. These models are based on generalized telegraph processes: Markov random flows with alternating velocities and jumps occurring when the velocities are switching. While such markets may admit an arbitrage opportunity, the model under consideration is arbitrage-free and complete if directions of jumps in stock prices are in a certain correspondence with their velocity and interest rate behaviour. An analog of the Black-Scholes fundamental differential equation is derived, but, in contrast with the Black-Scholes model, this equation is hyperbolic. Explicit formulas for prices of European options are obtained using perfect and quantile hedging.

2007-01-01

361

No chaos in brane-world cosmology  

Energy Technology Data Exchange (ETDEWEB)

We discuss the asymptotic dynamical evolution of spatially homogeneous brane-world cosmological models close to the initial singularity. We find that generically the cosmological singularity is isotropic in Bianchi type IX brane-world models and consequently these models do not exhibit Mixmaster or chaotic-like behaviour close to the initial singularity. We argue that this is typical of more general cosmological models in the brane-world scenario. In particular, we show that an isotropic singularity is a past-attractor in all orthogonal Bianchi models and is a local past-attractor in a class of inhomogeneous brane-world models. (letter to the editor)

2002-04-21

362

Nanocrystallization of the amorphous Fe_1_4Ni_4_0Zr_7B_1_2 alloys studied by the Moessbauer spectroscopy  

International Nuclear Information System (INIS)

Formation of the soft magnetic nanostructure in amorphous Fe_1_4Ni_4_0Zr_7B_1_2 alloy due to heat treatment is studied by the Moessbauer, differential scanning calorimetry, and X-ray diffraction techniques. Annealing at temperatures 520-580 "oC leads to the formation of extremely soft nanocrystalline alloy as revealed by the rf-Moessbauer measurements. The superparamagnetic behaviour was observed for the alloy annealed at 620-640 "oC. At higher annealing temperatures good soft magnetic properties deteriorate. (author)

2001-09-23

363

Modeling of an electrically rechargeable alkaline zinc-air battery  

Energy Technology Data Exchange (ETDEWEB)

A numerical model has been developed to simulate the charging and discharge behaviour of an electrically rechargeable alkaline zinc-air battery. Further a galvanostatic experiment including three charge/discharge cycles has been performed. The cell voltages, the Zn electrode potentials versus a Zn reference, and the O{sub 2} electrode potentials versus a Zn reference calculated with the model are in fairly good agreement with the corresponding experimental data. The model is expected to be useful for zinc-air battery design and for analysis of experimental data. (author)

2003-03-01

364

Mixed structures in continuously cooled low-carbon automotive steels  

Energy Technology Data Exchange (ETDEWEB)

Mixed microstructures have been studied in low- carbon microalloyed steels suitable for automotive applications, after continuous cooling from the hot-rolled condition. Microstructural features such as polygonal ferrite, bainitic and acicular ferrite and microphase constituent are identified using transmission electron microscopy. The influence of these mixed structures on the tensile strength, impact toughness and fracture behaviour is examined. It is found that improvements in impact toughness as compared with microalloyed medium- carbon ferrite/pearlite steels can be achieved from these predominantly acicular structures developed by controlling alloy composition and continuous cooling of these lower carbon steels. (orig.).

1993-11-01

365

Mixed structures in continuously cooled low-carbon automotive steels  

International Nuclear Information System (INIS)

Mixed microstructures have been studied in low- carbon microalloyed steels suitable for automotive applications, after continuous cooling from the hot-rolled condition. Microstructural features such as polygonal ferrite, bainitic and acicular ferrite and microphase constituent are identified using transmission electron microscopy. The influence of these mixed structures on the tensile strength, impact toughness and fracture behaviour is examined. It is found that improvements in impact toughness as compared with microalloyed medium- carbon ferrite/pearlite steels can be achieved from these predominantly acicular structures developed by controlling alloy composition and continuous cooling of these lower carbon steels. (orig.).

1993-06-01

366

Minimal Polynomials of Some Matrices Via Quaternions  

CERN Document Server

This work provides explicit characterizations and formulae for the minimal polynomials of a wide variety of structured $4\\times 4$ matrices. These include symmetric, Hamiltonian and orthogonal matrices. Applications such as the complete determination of the Jordan structure of skew-Hamiltonian matrices and the computation of the Cayley transform are given. Some new classes of matrices are uncovered, whose behaviour insofar as minimal polynomials are concerned, is remarkably similar to those of skew-Hamiltonian and Hamiltonian matrices. The main technique is the invocation of the associative algebra isomorphism between the tensor product of the quaternions with themselves and the algebra of real $4\\times 4$ matrices.

2010-01-01

367

Magnetization reversal phenomena and domain wall behaviours in nanostructured magnetic systems  

International Nuclear Information System (INIS)

Several recent experiments on micro- (or nano-) structured samples of ferromagnetic materials are introduced. Magnetization reversal phenomena are investigated on submicron wire samples of trilayer structure using the giant magnetoresistance effect. Domain wall movements are sensitively monitored by resistivity measurements and the velocity of propagation is determined. The contribution of domain wall to the resistivity is argued from the results on artificially designed samples of a spring-magnet system. In circular dots of permalloy, the existence of vortex magnetization is confirmed and the reversal of the vortex core magnetization is studied from magnetic force microscopy measurements. (author)

2001-09-23

368

Magnetic properties of glasses from geothite industrial wastes recycling (FeOOH)  

International Nuclear Information System (INIS)

It has been carried out the magnetic properties determination for high iron oxide content glasses series obtained from a geothite red mud waste from the zinc hydrometallurgy and dolomite and glass cullet as main raw materials. It has been determined the magnetic susceptibility and magnetization values for the glasses here investigated. The results suggest that the magnetic behaviour are depending on the glass chemical composition, so that glasses can be differently classified like ferrimagnetic, ferromagnetic, superparamagnetic and paramagnetic. (Author) 6 refs.

369

Lack of awareness of symptoms in people with dementia: the structural and functional basis  

British Library Electronic Table of Contents (United Kingdom)

AbstractObjective To review studies investigating the brain correlates of unawareness of cognitive and behavioural symptoms in people with dementia. Design A detailed search of the literature was conducted to include all the peer-reviewed studies published in English aimed at identifying the structural or functional brain correspondents of unawareness in dementia patients. Their results were interpreted in relation to the methodological differences in terms of type of dementia studied, the protocol adopted to measure lack of awareness, the imaging techniques employed, the experimental designs and statistical analyses performed. Results Eighteen studies undertaken to explore the functional and structural correlates of unawareness of cognitive symptoms in dementia were identified. Although t...

2011-01-01

370

JOINT PROBABILITIES FOE ENVIRONMENTAL LOADS (OCE 90)  

Environmental Research Database

ObjectivesObjectives Not AvailableDescriptionThis proposal seeks to extend what is currently the most comprehensive offshore environmental data collection programme at a platform on the UKGS involving continuous collection of wave height and direction, wind speed and direction, current and wave particle kinematics. Data has been collected with this system since 1994 and the proposal is to extend this until 1999 thus providing an extensive set of storm data collected at 5Hz which will allow examination of the joint behaviour of wave, wind [continued...

1998-01-16

371

Investigation of FP paths during hypothetical severe accident as a result of Small Break LOCA of WWER-1000 reactor type  

International Nuclear Information System (INIS)

Modelling the behaviour of fission product (FP) in a nuclear reactor coolant system (RCS) undergoing a hypothetical severe accident is an important step in the evaluation of radioactive release outside a nuclear power plant. This paper scrutinize Small Break LOCA sequence for WWER1000 reactor in order to investigate the possible paths for release of FP from fuel pallets to the reactor containment. Contemporaneous computer code for simulation of RCS will be use for the analysis. The results from analysis of fuel damage and release of FP trough the break of cold leg are present. (author)

2006-04-01

372

Inorganic astatine chemistry: Formation of complexes of astatine  

Energy Technology Data Exchange (ETDEWEB)

The nature and properties of inorganic /sup 211/At-species formed in aqueous solutions under alkaline, neutral, acidic and oxidative conditions are studied through extraction of At with a variety of organic solvents, followed by the determination of the chromatographic, re-extraction and interaction behaviour of the extracted activity. It is concluded from the Rsub(f) values (on SiO/sub 2/) and the different affinities for a large amount of additives, that the extracted activity - formerly denoted as At-zero - exists of AtX compounds that may form AtXLsub(u) complexes, depending on the kind of solvent (L) used.

1983-01-01

373

Inorganic astatine chemistry: Formation of complexes of astatine  

International Nuclear Information System (INIS)

The nature and properties of inorganic "2"1"1At-species formed in aqueous solutions under alkaline, neutral, acidic and oxidative conditions are studied through extraction of At with a variety of organic solvents, followed by the determination of the chromatographic, re-extraction and interaction behaviour of the extracted activity. It is concluded from the Rsub(f) values (on SiO_2) and the different affinities for a large amount fo additives, that the extracted activity - formerly denoted as At-zero - exists of AtX compounds that may form AtXLsub(u) complexes, depending on the kind of solvent (L) used. (orig.).

374

Immersions of Einstein-Riemann spacetimes in six-dimensional flat spaces  

International Nuclear Information System (INIS)

Each choice of an arbitrary nonzero function f of the four immersion parameters is shown to determine 16N[f] distinguishable classes of two-parameter families of immersions of Einstein-Riemann spacetimes in six-dimensional flat spaces, where N[f] is the number of regular immersion parameter domains. The metric tensors, curvature tensors and the immersion loci are calculated in a closed form, and these calculations involve only finitely many algebraic operations. The presence of the arbitrary function provides the opportunity for study of the behaviour of multiple isolated singularities and/or 'shape' functions in general relativity.

2002-09-21

375

Fourth international seminar on horizontal steam generators  

Energy Technology Data Exchange (ETDEWEB)

The general objective of the International Seminars of Horizontal Steam Generator Modelling has been the improvement in understanding of realistic thermal hydraulic behaviour of the generators when performing safety analyses for VVER reactors. The main topics presented in the fourth seminar were: thermal hydraulic experiments and analyses, primary collector integrity, feedwater distributor replacement, management of primary-to-secondary leakage accidents and new developments in the VVER safety technology. The number of participants, representing designers and manufacturers of the horizontal steam generators, plant operators, engineering companies, research organizations, universities and regulatory authorities, was 70 from 10 countries.

1997-12-31

376

Flatte-like distributions and the a{sub 0}(980)/f{sub 0}(980) mesons  

Energy Technology Data Exchange (ETDEWEB)

We explore the features of Flatte-like parametrizations. In particular, we demonstrate that the large variation in the absolute values of the coupling constants to the {pi}{eta} (or {pi}{pi}) and K anti K channels for the a{sub 0}(980) and f{sub 0}(980) mesons that one can find in the literature can be explained by a specific scaling behaviour of the Flatte amplitude for energies near the K anti K threshold. We argue that the ratio of the coupling constants can be much better determined from a fit to experimental data. (orig.)

2005-03-01

377

Electro-excitation of the 1/sup +/ state at Esub(x)= 3. 486 MeV in /sup 88/Sr  

Energy Technology Data Exchange (ETDEWEB)

The differential cross section for excitation of the 1/sup +/ state at Esub(x)=3.486 MeV in /sup 88/Sr by inealstic electron scattering has been measured for values of the momentum transfer q between 0.22 and 2.57 fm/sup -1/. Both nuclear core polarization and ..delta..-hole polarization seem to be necessary to describe the observed reduction of the B(M1) value and data at low q and the behaviour of the cross section at intermediate values of q. 42 references.

1984-07-23

378

Electro-excitation of the 1"+ state at Esub(x)= 3.486 MeV in "8"8Sr  

International Nuclear Information System (INIS)

The differential cross section for excitation of the 1"+ state at Esub(x)=3.486 MeV in "8"8Sr by inealstic electron scattering has been measured for values of the momentum transfer q between 0.22 and 2.57 fm"-"1. Both nuclear core polarization and #DELTA#-hole polarization seem to be necessary to describe the observed reduction of the B(M1) value and data at low q and the behaviour of the cross section at intermediate values of q. (orig.).

379

Effects of carbocalcitonin treatment on PAGET's disease assessed by quantitative bone scintigraphy  

International Nuclear Information System (INIS)

Sixteen patients with PAGET's disease of bone underwent quantitative bone scintigraphy with "9"9"mTc-MDP before and after a long-term treatment with carbocalcitonin, a synthetic analogue of eel calcitonin. The radionuclide study consisted in the blood pool and bone uptake measurement and in the bone avidity calculation (bone uptake - blood pool ratio). In our patients, a significant decrease in bone uptake and bone avidity was found, whereas the blood pool remained statistically unchanged. This behaviour could be accounted for the shift of the compact bone to a lamellar pattern. (orig.).

380

Effects of carbocalcitonin treatment on PAGET's disease assessed by quantitative bone scintigraphy  

Energy Technology Data Exchange (ETDEWEB)

Sixteen patients with PAGET's disease of bone underwent quantitative bone scintigraphy with /sup 99m/Tc-MDP before and after a long-term treatment with carbocalcitonin, a synthetic analogue of eel calcitonin. The radionuclide study consisted in the blood pool and bone uptake measurement and in the bone avidity calculation (bone uptake - blood pool ratio). In our patients, a significant decrease in bone uptake and bone avidity was found, whereas the blood pool remained statistically unchanged. This behaviour could be accounted for the shift of the compact bone to a lamellar pattern.

1988-06-01

381

Dynamics of the Edge Transport Barrier at Plasma Biasing on the Castor Tokamak  

International Nuclear Information System (INIS)

A clear and reproducible transition to a regime with an improved particle confinement is routinely observed on the CASTOR tokamak, if the biasing electrode is inserted deep enough into the plasma (r/a?0.5) and biased up to +250 V. The steepening of the radial profiles of the plasma density and potential demonstrate the formation of a transport barrier just inside the last closed flux surface. Fast relaxations of the edge plasma parameters, with a frequency of about 10 kHz, are observed when the average radial electric field within the barrier prevails values of about 20 kV/m. A detailed analysis of the spatial-temporal behaviour of these relaxations is presented.

2006-01-01

382

Dry aerosol resuspension after a hydrogen deflagration in the containment  

International Nuclear Information System (INIS)

During a hypothetical severe incident in a nuclear power plant with core meltdown a large part of radioactive material is present as aerosol particles in the reactor containment. In current severe accident containment codes the potential influences of hydrogen combustions on the behaviour of aerosols are not considered. Among other effects dry resuspension can increase the aerosol concentration in the atmosphere. Already deposited aerosol material can be re-released into the containment atmosphere by atmospheric currents induced by hydrogen deflagrations or by other phenomena like steam explosions. The objective is to assess the possible influence of this dry resuspension effect on the radioactive source term. (author)

2007-09-10

383

Dirac equation on a G_2 manifold  

CERN Document Server

We find a large family of solutions to the Dirac equation on a manifold of $G_2$ holonomy asymptotic to a cone over $S^3 \\times S^3$, including all radial solutions. The behaviour of these solutions is studied as the manifold developes a conical singularity. None of the solutions found are both localised and square integrable at the origin. This result suggests that M-theory on the conifold over $S^3\\times S^3$ does not produce a chiral theory. The approach here is complementary to previous analyses using dualities and anomaly cancellation which found chiral fermions on all known $G_2$ conifolds except that over $S^3\\times S^3$.

2002-01-01

384

Determination of charge carrier mobility in poly(3hexylthiophene) with different current transient measurement techniques  

Energy Technology Data Exchange (ETDEWEB)

The carrier mobility in organic disordered materials, such as conjugated polymers, plays an important role in understanding the behaviour of organic electronic devices. We investigated the mobility of charge carriers in poly(3-hexylthiophene) (P3HT) using different current transient measurement methods. Besides the conventional transient photoconductivity experiment, time-of-flight (TOF), we used extraction current transient techniques, such as charge carrier extraction by linearly increasing voltage (CELIV), probing equilibrium carriers instead. The field and temperature dependence of the mobility are discussed in view of hopping transport in a Gaussian density of states distribution.

2007-07-01

385

Design parameters for tube cavity receivers in solar power plants  

Energy Technology Data Exchange (ETDEWEB)

The design of a solar heated cavity receiver transferring 60 MW of thermal energy to the working medium (air) for a closed-cycle gas turbine is described. The gas turbine plant with its cycle layout is presented. Then the tubes for the receiver are designed taking into account thermal and mechanical loads. It is shown how the occurring stresses are influenced by the destribution of the locally absorbed hat flux. Calculations for an existing coal fired air heater of a closed-cycle gas turbine give a first impression of the long-term behaviour to be expected of the receiver tubes.

1981-01-01

386

Dark matter in the universe  

International Nuclear Information System (INIS)

Until recently little more was known than that dark matter appears to exist; there was little systematic information about its properties. Only in the past several years was progress made to the point where dark matter density distributions can be measured. For example, with accurate rotation curves extending over large ranges in radius, decomposing the effects of visible and dark matter to measure dark matter density profiles can be tried. Some regularities in dark matter behaviour have already turned up. This volume includes review and invited papers, poster papers, and the two general discussions. (Auth.).

1985-06-24

387

Damping measurements of the magnesium wrought alloys AZ31, AZ61 and AZ80 after indirect and hydrostatic extrusion  

Energy Technology Data Exchange (ETDEWEB)

Magnesium cast parts as well as indirectly and hydrostatically extruded profiles were used in order to investigate the influence of different microstructures on the damping behaviour of magnesium AZ-alloys. Especially, hydrostatic extrusion leads to a significant grain refinement in the extruded profile compared to indirect extrusion. Strain dependent damping measurements were carried out at room temperature using alloys AZ31, AZ61 and AZ80. Damping was determined as the logarithmic decrement of free bending beam vibrations. The results of these measurements after indirect and hydrostatic extrusion are shown and discussed. (orig.)

2005-07-01

388

Conversion of steam turbines for new ideas of use. Umbau von Dampfturbinen fuer neue Einsatzkonzeptionen  

Energy Technology Data Exchange (ETDEWEB)

The invention concerns the conversion of steam turbines, particularly condensation turbines, for the economic coupling of process steam and heating steam. The conversion occurs by retaining the basic construction of foundations, housing and bearings as support group and coupling member and matching the specially developed construction for the idea of use into the existing housing, and inserting the rotor into the shaft unit. By having the unchanged supports of the housing and the bearings of the shaft unit, the elasticity in expansion and the vibration behaviour of the turbine are retained and the conversion costs can be lowered.

1992-08-20

389

Computer-aided diagnosis of bone tumours and tumour-like skeletal abnormalities in childhood  

Energy Technology Data Exchange (ETDEWEB)

The method, use and results of computer-aided diagnosis of bone tumours and tumour-like skeletal abnormalities in childhood are described. One hundred and twentyone histologically verified cases were analysed and subjected to computer-aided diagnosis. Statistical methods were used, resulting in an accuracy of 96.7% and 91.7% respectively. In order to obtain additional confirmation of the diagnosis, a so-called growth rate was calculated by the computer. This proved to be a reliable criterion for evaluating the biological behaviour of tumours, irrespective of the histological diagnosis. The reasons for misdiagnosis were discussed. Attention is drawn to the importance of an accurate analysis of the radiographs and its input into the computer.

1982-06-01

390

Complex radiation degradation behaviour of PVC materials under accelerated aging conditions  

International Nuclear Information System (INIS)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the levelling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests. (author).

1982-10-01

391

Comparison of the green- and infrared-stimulated luminescence of feldspar  

Energy Technology Data Exchange (ETDEWEB)

The differences are highlighted of various aspects of behaviour of the luminescence signal from feldspar when stimulated by green light and when stimulated by infrared radiation. In respect of bleaching, a comparison is made of the influence of white light (daylight) on the two stimulated luminescence signals, as well as a comparison of the influence of infrared exposure on the green-stimulated signal with the influence of green exposure on the infrared-stimulated signal. The influence of preheating on the two stimulated signals is also compared. Light-emitting diode systems were used for both green and infrared stimulation. The observations are considered in relation to the mechanism relevant to green- and infrared-stimulated luminescence from feldspar. (author).

1994-04-01

392

Comparison of the green- and infrared-stimulated luminescence of feldspar  

International Nuclear Information System (INIS)

The differences are highlighted of various aspects of behaviour of the luminescence signal from feldspar when stimulated by green light and when stimulated by infrared radiation. In respect of bleaching, a comparison is made of the influence of white light (daylight) on the two stimulated luminescence signals, as well as a comparison of the influence of infrared exposure on the green-stimulated signal with the influence of green exposure on the infrared-stimulated signal. The influence of preheating on the two stimulated signals is also compared. Light-emitting diode systems were used for both green and infrared stimulation. The observations are considered in relation to the mechanism relevant to green- and infrared-stimulated luminescence from feldspar. (author).

1993-07-01

393

Assessment of RELAP5/MOD2 against a natural circulation experiment in Nuclear Power Plant Borssele. International Agreement Report  

Energy Technology Data Exchange (ETDEWEB)

As part of the ICAP (International Code Assessment and Applications Program) agreement between ECN (Netherlands Energy Research Foundation) and USNRC, ECN has performed a number of assessment calculations for the thermohydraulic system analysis code RELAP5/MOD2/36.05. This document describes the assessment of this computer program versus a natural circulation experiment as conducted at the Borssele Nuclear Power Plant. The results of this comparison show that the code RELAP5/MOD2 predicts well the natural circulation behaviour of Nuclear Power Plant Borssele.

1993-07-01

394

Application of neutron radiography to visualization of multiphase flows  

Energy Technology Data Exchange (ETDEWEB)

Visualizations by real-time neutron radiography are demonstrated of various flow patterns of nitrogen gas-water two-phase flow in a stainless-steel tube, water inverted annular flow in a stainless-steel tube, flashing flow in an aluminium nozzle and fluidized bed in aluminium tube and vessels. Photographs every 1/60 s are presented by an image processing method to show the dynamic behaviours of the various flow patterns. It is shown that this visualization method can be applied efficiently to multiphase flow researches and will be applicable to multiphase flows in industrial machines. (author).

1990-04-01

395

Application of neutron radiography to visualization of multiphase flows  

International Nuclear Information System (INIS)

Visualizations by real-time neutron radiography are demonstrated of various flow patterns of nitrogen gas-water two-phase flow in a stainless-steel tube, water inverted annular flow in a stainless-steel tube, flashing flow in an aluminium nozzle and fluidized bed in aluminium tube and vessels. Photographs every 1/60 s are presented by an image processing method to show the dynamic behaviours of the various flow patterns. It is shown that this visualization method can be applied efficiently to multiphase flow researches and will be applicable to multiphase flows in industrial machines. (author).

1990-01-01

396

A percolation process on the binary tree where large finite clusters are frozen  

CERN Document Server

We study a percolation process on the planted binary tree, where clusters freeze as soon as they become larger than some fixed parameter N. We show that as N goes to infinity, the process converges in some sense to the frozen percolation process introduced by Aldous. In particular, our results show that the asymptotic behaviour differs substantially from that on the square lattice, on which a similar process has been studied recently by van den Berg, de Lima and Nolin.

2011-01-01

397

A dependence of cumulative pion production cross sections in proton-nuclear interactions at high energies  

International Nuclear Information System (INIS)

The A dependence of cumulative pion production yield cross sections on the basis of the comparison of the data on relative pion yields on Be,C,Al,Ti,Mo and W nuclei at the 159 deg angle laboratory system for the incident proton energy E_0 from 25 to 62 GeV is considered. The regular A dependence on cumulative variable X is noted. The results are compared with the data at E_0< 10 GeV. A possible interpretation of the observed behaviour on the basis of the hypothesis of the flucton mechanism of the pion production in the cumulative region is discussed. 15 refs.; 4 figs.

398

Visual search behaviour in skeletal radiographs: a cross-speciality study  

Energy Technology Data Exchange (ETDEWEB)

Aim: To determine whether experience improves the consistency of visual search behaviour in fracture identification in plain radiographs, and the effect of specialization. Material and methods: Twenty-five observers consisting of consultant radiologists, consultant orthopaedic surgeons, orthopaedic specialist registrars, orthopaedic senior house officers, and accident and emergency senior house officers examined 33 skeletal radiographs (shoulder, hand, and knee). Eye movement data were collected using a Tobii 1750 eye tracker with levels of diagnostic confidence collected simultaneously. Kullback-Leibler (KL) divergence and Gaussian mixture model fitting of fixation distance-to-fracture were used to calculate the consistency and the relationship between discovery and reflective visual search phases among different observer groups. Results: Total time spent studying the radiograph was not significantly different between the groups. However, the expert groups had a ...

2007-11-15

399

Tribological behaviour of Ti-Al-B-N-based PVD coatings  

Energy Technology Data Exchange (ETDEWEB)

PVD-coatings based on TiB{sub 2} are expected to show high wear resistance and low tendency of adhesion on metal forming tools. Coating adhesion and morphology can be modified over a wide range by varying the content of nitrogen (N{sub 2}) and the deposition parameters power and bias voltage. All coatings were deposited using commercial unbalanced magnetron equipment, the deposition was homogeneous in a volume of 400 x 400 x 400 mm{sup 3}. Hipped and hot pressed TiB{sub 2}-targets were used, nitrogen (N{sub 2}) was added as gas, Ti and Al by a solid Ti-Al-target. The tribological behaviour was tested by a pin-on-disc wear test. The coatings investigated were TiB{sub 2}, TiAlB(N), TiAl(N) and TiB{sub 2}/TiAl(N). As counterpart in the pin-on-disc wear test, 6 mm diameter spheres of steel (100Cr6), aluminium, brass and bronze were used. The experiments showed a non-uniform wear behaviour. For the combinations TiAlB(N) and TiB{sub 2} versus ...

1996-12-15

400

The effects of helium on the embrittlement and hardening of boron doped EUROFER97 steels  

International Nuclear Information System (INIS)

The role of helium in a process of embrittlement and hardening of RAFM steels was investigated in EUROFER97 based experimental heats, ADS2, ADS3 and ADS4, that were doped with different contents of natural B and the separated 10B-isotope (0.008-0.112 wt.%). The neutron irradiation of the boron doped and the reference RAFM steels was performed in the Petten High Flux Reactor up to 16.3 dpa at different temperatures between 250 and 450 deg. C. The embrittlement behaviour and hardening was investigated by instrumented Charpy-V tests with subsize specimens. Irradiation lead to generation of 84, 432 and 5580 appm He in ADS2, ADS3 and ADS4 steels, respectively. At irradiation temperatures Tirr ? 350 deg. C the boron doped steals show progressive embrittlement and reduction of toughness with increasing helium amount. The analysis of the hardening vs. embrittlement behaviour at Tirr ? 350 deg. C reveals hardening nature of embrittlement for helium ...

2008-12-01

401

Study of the rheological behaviour of corium/concrete mixtures; Etude du comportement rheologique de melanges issus de l'interaction corium/beton  

Energy Technology Data Exchange (ETDEWEB)

In the hypothetical event of a severe accident in a Light Water Reactor, scenarios in which the reactor pressure vessel (RPV) fails and the core melt mixture (called corium) relocates into the reactor cavity, cannot be excluded. The viscosity (in fact, corium rheological behaviour) plays a major role in many phenomena such as core melt down, discharge from reactor pressure vessel, interaction with structural materials (concrete,...) and spreading in a core-catcher. For these reasons, it is important to be able to predict the rheological behaviour of corium melts of different compositions (essentially based on UO{sub 2}, ZrO{sub 2}, Fe{sub x}O{sub y} and Fe for in-vessel scenarios, plus SiO{sub 2} and CaO for ex-vessel scenarios) at temperatures above solidus temperature. In the case of corium-concrete mixtures, the increase of viscosity depends not only on the increase of particles in the melts but also on the increase of the residual liquid ...

1999-09-24

402

Spin freezing in the re-entrant spin glass FeNiMn close to the frustration limit  

Energy Technology Data Exchange (ETDEWEB)

In the invar alloy (Fe{sub 0.65}Ni{sub 0.35}){sub 1-} {sub x} Mn {sub x} we measured the magnetic form factor s(Q) and the intermediate scattering function s(Q,t) for a sample close to the critical Mn concentration (x {sub c}=0.139), at which the sample turns to a re-entrant spin glass phase. The aim was to check whether the magnetic behaviour would approach the Q-independent relaxation behaviour of a classical spin glass when x=x {sub c}. The experiment showed a quite similar spin freezing as for a more ferromagnetic sample with x=0.113. The intermediate scattering function and the form factor were determined by paramagnetic NSE. The normalized scattering function S(Q,t)=s(Q,t)/s(Q)=exp[(-{gamma}t) {sup n}] was fitted by stretched exponential decay. As a function of temperature T<200 K the inverse time constant {gamma} showed the change of more than four orders of magnitude from frozen spin glass (T=60 K to T=100 K), where the ...

2007-07-15

403

Radionuclide release from irradiated Th-Pu mox fuel  

International Nuclear Information System (INIS)

Plutonium and minor actinides produced as by-products of the UO_2 nuclear cycle could be considered as waste or energy source depending on the strategy selected in the nuclear energy programme. Considering Pu and Minor Actinides as a source, they can be burned in existing water reactor for diminishing the radiotoxicity of the spent fuel, it is necessary to use 'inactive' materials as matrix like ThO_2. ThO_2 matrix has demonstrated its Pu burning efficiency and higher corrosion resistance than UO_2. Uranium-plutonium mixed oxide (MOX) fuel efficiency is low because the presence of U in MOX results in the creation of some new Pu under irradiation. The dissolution behaviour of irradiated (Th,Pu)O_2 pellets with burn-up of 38.8 MWd/kg Th has been studied in carbonated (20 mM HCO_3"-), deionised and granite ground water solution in a hot cell. The dissolution behaviour of Th, Pu, U and Np was studied in order to find out whether radionuclides ...

404

Quantum molecular dynamics and molecular interactions studied by NMR and INS[Nuclear magnetic resonance; Proton tunnelling; Hydrogen bond  

Energy Technology Data Exchange (ETDEWEB)

The wavefunction of a particle extends into the classically forbidden barrier region of the potential energy surface. The consequence of this partial delocalisation is the phenomenon of quantum tunnelling, an effect which enables a particle to penetrate a potential barrier of magnitude greater than the energy of the particle. The tunnelling probability is an exponential function of the particle mass. The effect is therefore an important contribution to the behaviour of light atoms, in particular the proton. The hydrogen bond has long been appreciated to be an essential component of many biological and chemical systems, and the proton transfer reaction in the hydrogen bond is fundamental to many of these processes. The proton behaviour in the hydrogen bonds of benzoic acid, acetylacetone and calix-4-arene has been studied. A variety of techniques, both experimental and computational, were adopted for the study of the three hydrogen bonded ...

2002-07-01

405

Index analysis and numerical solution of a large scale nonlinear PDAE system describing the dynamical behaviour of molten carbonate fuel cells  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with the efficient simulation of the dynamical behaviour of molten carbonate fuel cells (MCFCs). MCFCs allow an efficient and environmentally friendly energy production via electrochemical reactions. Their dynamics can be described by large scale systems of up to currently 22 nonlinear partial differential algebraic equations (PDAE). The paper also serves as a basis for later parameter identification and optimal control purposes. Therefore, the numerical simulations are particularly based on hierarchically embedded systems of PDAE, first of all in one space dimension. The PDAE are of mixed parabolic-hyperbolic type and are completed by nonlinear initial and boundary conditions of mixed type. For a series of embedded models in one space dimension, the vertical method of lines (MOL) is used throughout this paper. For the semi-discretization in space appropriate difference schemes are applied depending on the type of equations. The resulting system of ...

2005-02-01

406

Grazing incidence X-ray diffraction and neutron reflection studies of semi-crystalline polymer surfaces and interfaces[Polymers; Crystallisation behaviour  

Energy Technology Data Exchange (ETDEWEB)

This thesis is concerned with the crystallisation behaviour of polymers near to a free surface or a buried interface. The properties of polymers are expected to differ significantly near to an interface (either with air or another polymer), due to the contributions of (a) chain configurations induced at the interface, and (b) different mobilities between interfacial regions and the bulk of the sample. For a semi-crystalline polymer, properties such as the degree of crystallinity and the crystallisation kinetics may be enhanced near to a free surface. Grazing incidence x--ray diffraction (GIXD) is used to investigate such effects in poly(ethylene terphthalate) (PET), showing that a lower crystallisation temperature is obtained at the surface, and the crystallisation kinetics are faster at the surface for all temperatures. It is proposed that in thin films of PET, this surface-induced ordering provides nucleation sites for crystallisation in the bulk. GIXD is also ...

2002-07-01

407

Crack growth in welded turbine materials at elevated temperatures  

International Nuclear Information System (INIS)

Due to thermal gradients and load changes steam-turbine casings suffer combined creep-fatigue loading. Creep and fatigue portions depend on service conditions. Special interest is focused on the behaviour of creep-fatigue cracks, originated from potential defects due to construction and manufacturing weldments, on residual lifetime assessment. The project deals with the crack-growth behaviour at 530deg C and r.t. of welded and unwelded heat-resistant cast steels: 1% CrMoV-cast (GS-17 CrMoV 5 11, two melts: low and high V-content) and 12% CrMoV-cast (G-X 22 CrMoV 12 1). The crack planes of CT-specimens investigated, taken from manual arc-welded plates, were situated in the heat-affected zone (HAZ). The fatigue, creep and combined creep-fatigue crack-growth behaviour was investigated by means of low-frequency (0.5 and 0.05 Hz) tests, holding-time (20 min) tests and constant load tests up to about 5 000 h. Metallographic ...

1989-12-01

408

Gastric stromal tumors. CT findings; Tumori stromali gastrici. Aspetti con Tomografia Computerizzata  

Energy Technology Data Exchange (ETDEWEB)

Gastric stromal tumors are an ill-defined group of lesions arising from muscle wall cells and characterized by extremely variable biological patterns. Thanks to modern immunohistochemical and ultrastructural techniques, four main classes of these lesions have been identified, namely: (1) tumors with differentiation toward smooth muscle cells; (2) tumors with differentiation toward neural elements; (3) tumors with differentiation toward neural elements; (3) tumors with dual differentiation toward either cell type. It was investigated the yield of CT in diagnosing and characterizing gastric stromal tumors. It was retrospectively reviewed the CT findings of 38 patients (15 men and 23 women; mean age 51 years) with pathologically proven gastric stromal tumors, namely 31 of myoid origin, 4 of neural origin, 2 with both muscle and neural differentiation, 1 lacking differentiation with either cell type. The myoid tumors involved gastric fundus in 9/13 and 5/7 benign ...

2000-02-01

409

Mechanodynamical analysis of nickel-titanium alloys for orthodontics application; Analise mecanodinamica de ligas de niquel-titanio para aplicacao ortodontica  

Energy Technology Data Exchange (ETDEWEB)

Nickel-titanium alloys may coexist in more than one crystalline structure. There is a high temperature phase, austenite, and a low temperature phase, martensite. The metallurgical basis for the superelasticity and the shape memory effect relies in the ability of these alloys to transform easily from one phase to another. There are three essential factors for the orthodontist to understand nickel-titanium alloys behaviour: stress; deflection; and temperature. These three factors are related to each other by the stress-deflection, stress-temperature and deflection-temperature diagrams. This work was undertaken with the objective to analyse commercial nickel-titanium alloys for orthodontics application, using the dynamical mechanical analyser - DMA. Four NiTi 0,017 X 0,025'' archwires were studied. The archwires were Copper NiTi 35 deg C (Ormco), Neo Sentalloy F200 (GAC), Nitinol Superelastic (Unitek) and NiTi (GAC). The different mechanodynamical ...

2002-07-01

410

Crack growth behaviour of low alloy steels for pressure boundary components under transient light water reactor operating conditions (CASTOC)  

Energy Technology Data Exchange (ETDEWEB)

The CASTOC project addresses environmentally assisted cracking (EAC) phenomena in low alloy steels used for pressure boundary components in both Western type boiling water reactors (BWR) and Russian type pressurised water reactors (VVER). It comprises the four work packages (WP): inter-laboratory comparison test (WP1); EAC behaviour under static load (WP2), EAC behaviour under cyclic load and load transients (WP3); evaluation of the results with regard to their relevance for components in practice (WP4). The use of sophisticated test facilities and measurement techniques for the on-line detection of crack advances have provided a more detailed understanding of the mechanisms of environmentally assisted cracking and provided quantitative data of crack growth rates as a function of loading events and time, respectively. The effect of several major parameters controlling EAC was investigated with particular emphasis on the transferability of the ...

2004-07-01

411

Coupled effects of the precipitation of secondary species on the mechanical behaviour and chemical degradation of concretes; Les effets couples de la precipitation d'especes secondaires sur le comportement mecanique et la degradation chimique des betons  

Energy Technology Data Exchange (ETDEWEB)

Sulfate attack of cement-based materials remains an important problem for the durability assessment of containers and disposal engineering barriers dedicated to the long-term storage of radioactive wastes since underground water which may reach these elements contains small quantities of sulfates (7-31 mmol/1). This work contributes to the study of sulfate-induced damage mechanisms, to their understanding and modelling. The experimental phases of this study aimed at the understanding of the different physico-chemical phenomena involved during an external sulfate attack at following their evolution and their impact on the transport and mechanical properties of the material. Leaching experiments in pure water and in a solution of sodium sulfate (with a sulfate content of 15 mmol/1), have been performed simultaneously on OPC paste (w/c 0,4)in order to allow a comparison of test results. The frequent analysis of the leachant has shown a consumption of sulfate ions by the matrix, ...

2002-06-01

412

Workshop on dense granular flows  

Environmental Research Database

ObjectivesThe objective of this meeting will be to interface the two ends of the particulate flow spectrum - those working to understand the fundamentals of granular flows and those attempting to control particulate flows in an industrial setting - to develop solutions to the complex problems presented by dense granular flows. We will aim~%~~%~to provide a forum for the interface between practical users of particulate technology and the developers of theories for understanding granular flow;~%~to present [continued...]DescriptionIn practical situations such as those met in industry where segregation and mixing are important, understanding particulate flows is complex due to the presence of polydispersity, anisotropy and complex grain morphology. In attempting to model such systems, many of these features are generally ignored, except perhaps through empirical parameter fitting. Developing a theory to include these effects is a considerable challenge, and made more ...

2009-01-08

413

Weathering behaviour and construction suitability of dimension stones from the Drei Gleichen area (Thuringia, Germany)  

British Library Electronic Table of Contents (United Kingdom)

The construction suitability of a dimension stone depends on its weathering properties along with the petrology and the petrophysical properties. The aim of this study was to evaluate the suitability of the dimension stones from the ?Drei Gleichen? area for construction and replacement purposes. In total, six sandstones (Ingersleben, Wachsenburg, Hindfelden, Seeberg, R?hnberg, Gleichenberg; Upper Triassic) as well as two carbonates (Wachsenburg sinter; Quaternary, Wandersleben dolomite; Middle Triassic) were analysed. The results from our laboratory and on-site studies of the dimension stones show that rocks from the same stratigraphic layer, like the sandstones from the upper Triassic, can show major differences in their petrophysical and weathering properties. These differences are attri...

2011-01-01

414

Waste and dust utilisation in shaft furnaces  

Energy Technology Data Exchange (ETDEWEB)

Wastes and dusts from steel industry, non-ferrous metallurgy and other branches can be utilised e.g. in agglomeration processes (sintering, pelletising or briquetting) and by injection into shaft furnaces. This paper deals with the second way. Combustion and reduction behaviour of iron- and carbon-rich metallurgical dusts and sludges containing lead, zinc and alkali as well as other wastes with and without pulverised coal (PC) has been studied when injecting into shaft furnaces. Following shaft furnaces have been examined: blast furnace, cupola furnace, OxiCup furnace and imperial-smelting furnace. Investigations have been done at laboratory and industrial scale. Some dusts and wastes under certain conditions can be not only reused but can also improve combustion efficiency at the tuyeres as well as furnace performance and productivity.

2005-07-01

415

Virtual reality in acquired brain injury upper limb rehabilitation: Evidence-based evaluation of clinical research  

British Library Electronic Table of Contents (United Kingdom)

Primary objective: Acquired brain injury (ABI) is associated with significant cognitive, behavioural, psychological and physical impairment. Hence, it has been important to leverage assessment approaches in rehabilitation by using current and emerging technologies, including virtual reality (VR). A number of VR rehabilitation programmes have been designed in recent years, mainly to improve upper limb function. However, before this technology gains widespread use, evaluation of the scientific evidence supporting VR-assisted rehabilitation is needed. The present review aimed to assess the rationale, design and methodology of research investigating the clinical impact of VR on ABI upper-limb rehabilitation. Research design: A total of 22 studies were surveyed using a Cochrane-style review. Re...

2009-01-01

416

Thermal diffusivity of homogeneous SBR MOX fuel with a burn-up of 35 MWd/kgHM  

International Nuclear Information System (INIS)

The effect of burn-up on the thermal conductivity of homogeneous SBR MOX fuel is investigated and compared with standard UO_2 LWR fuel. New thermal diffusivity results obtained on SBR MOX fuel with a pellet burn-up of 35 MWd/kgHM are reported. The thermal diffusivity measurements were carried out at three radial positions using a shielded 'laser-flash' device and show that the thermal diffusivity increases from the pellet periphery to the centre. The fuel thermal conductivity was found to be in the same range as for UO_2 of similar burn-up. The annealing behaviour was characterized in order to identify the degradation due to the out-of-pile auto-irradiation.

2010-05-31

417

The relationship between periodontitis and metabolic syndrome among a Korean nationally representative sample of adults  

British Library Electronic Table of Contents (United Kingdom)

Abstract Aims: The aim of this study was to examine whether metabolic syndrome (MS) is associated with periodontitis in a representative sample of Korean adults, who were involved in the Fourth Korea National Health and Nutrition Examination Survey (KNHANES). Materials and Methods: A total of 7178 subjects over the age of 19 years who participated in KNHANES were examined. MS was defined as the definition proposed by the National Cholesterol Education Program Adult Treatment Panel III and the abdominal obesity cut-off line based on Korean Society for the Study of Obesity. The periodontal status was assessed by the Community Periodontal Index. Multivariate logistic regression analysis was carried out adjusting for the sociodemographics, oral health behaviours and status, and health behaviou...

2011-01-01

418

The novel 'OLGA' technology for complete tar removal from biomass producer gas  

Energy Technology Data Exchange (ETDEWEB)

A new process for the removal of tar from biosyngas, OLGA (Oil and Gas Washer), is presented. This gas cleaning technology is based on physical principles and is designed to eliminate tar problems that relate to fouling and er pollution. The applied principles are confirmed by experimental validation. OLGA can be operated without suffering from harmful effects on important gasification characteristics as cold gas efficiency, gasifier simplicity, and feedstock flexibility. Some fundamental considerations in the development of OLGA are discussed. Amongst these is a different approach to the tar problem. This approach does not consider the total tar content as decisive in the evaluation of gas cleaning equipment. Instead, evaluation is focussed on whether tar properties as condensation behaviour and water solubility can still occur. A biosyngas free of tar should therefore be synonymous to a biosyngas that is free of tar related problems.

2002-10-14

419

The effect of trace elements on the fatigue behaviour of a carbide-hardened Fe-Ni-Cr alloy. Der Effekt von Spurenelementen auf das Zeitstandverhalten einer karbidverfestigten Fe-Ni-Cr-Legierung  

Energy Technology Data Exchange (ETDEWEB)

Fatigue tests were accomplished with a series of specimens doped with trace elements of a hardened Fe-Ni-Cr alloy, cast and hardened with intermetallic phases for determining the influence of these elements on the high temperature strength properties. The results of extensive fatigue tests show that even small contents of Te, Bi, Se, Pb, Tl and Zn considerably influence the life and creep processes especially after longer running periods, when added individually or combinedly. In contrast to this, the fatigue ductility is reduced by trace element additions even with short running periods. The order in which the metallic trace elements influence the fatigue properties nearly correlates with earlier work concerning Ni- and Co-superalloys. (orig.)

1993-01-01

420

The compatibility of alloy 800 in HTR atmospheres  

International Nuclear Information System (INIS)

A thermodynamic analysis of the behaviour of Alloy 800 in helium based atmospheres relevant to the High Temperature Gas Cooled Reactor indicates that, depending upon the precise gas composition, oxidation and carburisation, or carburisation alone may be expected. The prime influence appears to be the moisture level. The morphology and structure of the reaction products are discussed. It is shown that the 'reactive' elements chromium, manganese, titanium and silicon are concentrated in the oxide scale which is normally duplex in structure. Aluminium oxide is formed at grain boundaries and in an internal oxidation zone together with titanium and sometimes silicon. In carburising conditions, mixed titanium-chromium carbides are formed. When this occurs, intergranular penetration is maximised. Weight gain data are assessed and briefly described and a tentative model for the mechanism of corrosion of Alloy 800 in HTR helium is proposed. Areas for further work are ...

421

The ageing of CANDU steam generator due to localized corrosion  

International Nuclear Information System (INIS)

The Steam Generator (SG) tubing degradation caused by corrosion and other age-related mechanisms continues to be a significant safety and cost concern for many Nuclear Power Plants (NPP). The understanding of the steam generator ageing mechanisms is the key to effective management of steam generator ageing and consists of the knowledge of steam generator materials and these one properties, stressors and operating conditions, like degradation sites and wear mechanisms. The principal types of corrosion are presented which can occur in CANDU steam generator. There are also presented the operation conditions, the specifications referring to the water chemistry and the construction materials of Steam Generator, the factors that have a great influence on the corrosion behaviour during the whole exploitation period of this equipment. (R.P.)

2001-09-17

422

The PANDA facility and first test results  

International Nuclear Information System (INIS)

The PANDA test facility at the Paul Scherrer Institute is used to study the long-term performance of the Simplified Boiling Water Reactor's passive containment cooling system. The PANDA tests demonstrate performance on a larger scale than previous tests and examine the effects of any non-uniform spatial distributions of steam and non-condensable gases in the system. The facility is in 1:1 vertical scale and 1:25 scale for volume, power etc. Extensive facility characterization tests and steady-state passive containment condenser performance tests are presented. The results of the base case test of a series of transient system behaviour tests are reviewed. The first PANDA tests exhibited reproducibility, and indicated that the Simplified Boiling Water Reactor's containment is likely to be favorably responsive and highly robust to changes in the thermal transport patterns. (orig.).

423

The NCRP wound model: development and application.  

Science.gov (United States)

The US National Council on Radiation Protection and Measurements, in collaboration with the International Commission on Radiological Protection, has been developing a biokinetic and dosimetric model for radionuclide-contaminated wounds. The finalised model is described briefly in this paper, together with the scientific basis and application. The multicompartment model uses first-order linear biokinetics to describe the retention and clearance of a radionuclide deposited in a wound site using seven default retention categories. Examples using plutonium nitrate in colloidal form and uranium in metal fragments show the behaviour of the less soluble forms of radionuclides in wounds, in which long-term retention is predicted. Using uranium as an example, the wound model is coupled to a uranium International Commission on Radiological Protection systemic model to predict urinary excretion patterns for different physicochemical forms of uranium. The latter application is ...

2007-08-31

424

Teaching medicine and allied disciplines in the 21st century--lessons from Ireland on the continuing need for reform  

Energy Technology Data Exchange (ETDEWEB)

This article identifies the imperatives behind the need to move away from teaching based on the transmission of a lot of facts to teaching that enables students to become lifelong learners. It reminds us that the over-riding goal is an education process that maximizes the ability of teachers to teach well and of students to learn effectively. It argues that the necessary reform process can only be successful if the three components of an education programme--the curriculum, teaching strategies and assessment--are reformed simultaneously to ensure that each is designed to produce more effective teaching and learning. It points to the literature that tells us what we know about factors affecting student behaviour and, in particular, notes the crucial factor of student perception of the requirement of the assessment regime. It recommends that Biggs' model of constructive alignment is used as the organizing principle of continuing reform.

2005-02-01

425

Tachyons in gravitational field  

International Nuclear Information System (INIS)

Behaviour of tachyons in gravitational field has been investigated by using imaginary as well as real superluminal Lorentz transformations. Using real superluminal transformations in four- and six-dimensional space-time, an expression for the gravitational force acting on a tachyon, moving along the tachyon corridor constructed to follow the tachyon geodesic, has been derived. The motion of a tachyon through a black hole has also been discussed and it is shown that the black hole acts like a gravitational tunnel for tachyons and the transition between the regions inside and outside the horizon can be understood as real superluminal transformations transforming a R"4=(r,t) world into a T"4=(t,r) world. 36 refs.. (author).

426

Surface effects of total coal-seam extraction by underground mining methods  

Energy Technology Data Exchange (ETDEWEB)

The paper gives a detailed overview of the history of subsidence engineering in South African collieries. Surface displacements resulting from total-seam extraction are discussed, and the important role of local geology is highlighted. It is shown that the differences in subsidence behaviour between South African and European collieries can be attributed to the presence of competent strata in the overburden of South African coal seams. Criteria are given for the prediction of the most important subsidence parameters, and a new model for the simulation of surface subsidence above total-extraction panels is introduced. The final section of the paper deals with the damage to surface structures caused by total-seam extraction. A brief summary of the most important undermining experiments in South African collieries is given, and it is concluded that local experiences of damage compare with those in Europe. 32 refs., 9 figs., 3 tabs.

1991-07-01

427

Study of oxygen diffusion in YBaCuO by isothermal internal friction. Etude par frottement interieur isotherme de la diffusion de l'oxygene dans YBaCuO  

Energy Technology Data Exchange (ETDEWEB)

The elastic behaviour of YBaCuO specimens has been studied by very low-frequency isothermal internal-friction measurements. A relaxation peak is observed which is attributed to oxygen atom jumps, between A(1/2 0 0) and B(0 1/2 0) sites, in the CuO planes of the orthorhombic phase. A limit relaxation time {tau}{sub 0}, 2.6 {center dot} 10{sup -15}s, and an activation energy, 1.3eV, have been obtained from the shift of the maximum damping frequency observed when the measurement temperature is changed. The proposed values for the limit relaxation time and the activation energy are in good agreement with those previously proposed in the literature.

1992-02-07

428

Structural and spectroscopic behaviour of YSr{sub 2}Cu{sub 3-x}M{sub x}O{sub 7{+-}y} phases with M=Ti,Fe,Co,Al,Ga,Pb  

Energy Technology Data Exchange (ETDEWEB)

A number of materials of composition YSr{sub 2}Cu{sub 3-x}MxO{sub 7{+-}y} with M = Ti, Fe, Co, Al, Ga and Pb were prepared by solid state reactions. They belong to the tetragonal P4/mmm space group and their unit cell parameters were determined and refined from X-ray powder data. The infrared spectra of the compounds were also recorded and are briefly discussed on the basis of their structural characteristics and by comparison with those of related materials. (orig.) 23 refs.

1998-12-01

429

Strings and QCD  

Energy Technology Data Exchange (ETDEWEB)

We point out that the occurrence of a large-distance ''Coulomb'' term in the static quark-antiquark potential is related to tachyons in the underlying string model. Thus, the tachyon contents determine the coefficient of the ''Coulomb'' term. For a scalar string, one has Luescher's result -(d-2) /24R, for a Neveu-Schwarz string one obtains -(d-2) /16R, whereas for the Ramond string (and strings without tachyons) the ''Coulomb'' term vanishes. Monte Carlo data for QCD prefers a ''Coulomb'' term. This is not inconsistent with the tachyonic origin of this term, since the large-distance behaviour of string models is consistent even with tachyons. Also, critical dimensions are not necessary at large distances.

1985-10-03

430

Status of PACTEL facility  

Energy Technology Data Exchange (ETDEWEB)

Since 1976, the Nuclear Engineering Laboratory of the Technical Research Centre of Finland and Lappeenranta University of Technology have cooperated in the field of nuclear reactor thermal-hydraulics. During these years, a series of experimental facilities (REWET-I, -II, -III, VEERA) simulating pressurized water reactors (PWRs) have been built. The newest facility, PACTEL (Parallel Channel Test Loop), is an experimental out-of-pile facility designed to simulate the major components and system behaviour of a commercial PWR during postulated small and medium size break loss-of-coolant accidents (LOCAs), natural circulation and operational transients. A PACTEL natural circulation experiment has been carried out as an OECD/NEA international standard problem ISP 33. (2 refs., 3 figs., 2 tabs.).

1993-12-31

431

Spin dynamics in Ho{sub 2}Ru{sub 2}O{sub 7}  

Energy Technology Data Exchange (ETDEWEB)

The spin relaxation processes within the pyrochlore Ho{sub 2}Ru{sub 2}O{sub 7} have been investigated by neutron scattering and bulk property techniques. A single-ion process, that is thermally activated, dominates the spin-spin relaxation spectrum above 2 K. Assuming Arrhenius behaviour, we found an activation energy {delta} = (329 {+-} 6) K and characteristic relaxation time {tau}{sub 0} (5.2 {+-} 0.3) x 10{sup -12} s in the paramagnetic state, akin to those found in the spin ice, Ho{sub 2}Ti{sub 2}O{sub 7}. Atlow temperature (T<95 K) the activation energy lowers and below 20 K the entropy and ac susceptibility are similar to that observed in other spin ice compounds within a 10 kOe field.

2005-11-09

432

Spin dynamics in Ho_2Ru_2O_7  

International Nuclear Information System (INIS)

The spin relaxation processes within the pyrochlore Ho_2Ru_2O_7 have been investigated by neutron scattering and bulk property techniques. A single-ion process, that is thermally activated, dominates the spin-spin relaxation spectrum above 2 K. Assuming Arrhenius behaviour, we found an activation energy #DELTA# = (329 #+-# 6) K and characteristic relaxation time #tau#_0 (5.2 #+-# 0.3) x 10"-"1"2 s in the paramagnetic state, akin to those found in the spin ice, Ho_2Ti_2O_7. Atlow temperature (T<95 K) the activation energy lowers and below 20 K the entropy and ac susceptibility are similar to that observed in other spin ice compounds within a 10 kOe field.

2005-11-09

433

Simulation of a flowing bed kiln for the production of uranium tetrafluoride; Simulation d'un four a lit coulant pour la production de tetrafluorure d'uranium  

Energy Technology Data Exchange (ETDEWEB)

A flowing bed kiln is a gas-solid reactor used in the civil nuclear fuel cycle for the successive conversion of uranium trioxide (UO{sub 3}) into uranium dioxide (UO{sub 2}) and then into uranium tetrafluoride (UF{sub 4}). A numerical model is developed which simulate the behaviour of this reactor in permanent regime. This model describes the physico-chemical phenomena involved, and combines a mechanistic approach in the vertical area of the kiln (resolution by the finite volumes method) and a systemic approach in the horizontal area, like in the model of cascade mixers. The first results have been obtained for reference operating conditions of the industrial kiln. Some possible improvements of the optimum temperature progression inside the kiln are evoked. (J.S.)

2001-07-01

434

Short-term under/overreaction, anticipation or uncertainty avoidance? Evidence from India  

British Library Electronic Table of Contents (United Kingdom)

We examine the short-term price behaviour of three, size-conditioned Indian stock market indices, in response to informational shocks. A standard mean-adjusted returns model as well as the GJR-GARCH specification point towards underreaction to negative events in the medium and small capitalization indices. Also, the pre-event coefficients are generally negative and statistically significant, regardless of the sign of the shock, thus ruling out information leaks. We uncover a stable abnormal volatility pattern which increases monotonically a few days before the shock before suddenly decreasing in magnitude on the event day and beyond. We suggest uncertainty avoidance as a potential explanation of these features. The results are fairly robust across alternative event selection procedures, ti...

2011-01-01

435

Shape of tachyons  

Energy Technology Data Exchange (ETDEWEB)

We study some aspects of the experimental behaviour of tachyons, in particular by finding out their <> shape. A Superluminal particle, which in its own rest frame is spherical or ellipsoidal (and with an infinite lifetime), would <> to a laboratory frame as occupying the whole region of space bound by a double cone and a two sheeted hyperboloid. Such a structure (the tachyon <>) rigidly travels with the speed of the tachyon. However, if the Superluminal particle has a finite lifetime in its rest frame, then in the laboratory frame it gets a finite space extension. As a by-product, we are able to interpret physically the imaginary units entering - as is well known - the transverse co-ordinates in the Superluminal Lorentz transformations. The various particular or limiting cases of the tachyon shape are thoroughly considered. Finally, some brief considerations concerning possible experiments to look for ...

1982-10-21

436

SPH simulations of accretion flow via Roche lobe overflow and via mass transfer from Be disk  

CERN Document Server

We compare the accretion flow onto the neutron star induced by Roche lobe overflow with that by the overflow from the Be disk, in a zero eccentricity, short period binary with the same mass transfer rate, performing three-dimensional Smoothed Particle Hydrodynamics simulations. We find that a persistent accretion disk is formed around the neutron star in both cases. The circularization radius of the material transferred via Roche lobe overflow is larger than that of the material transfered from the Be disk. Thus, the growth of the accretion disk in the former case becomes significantly slower than in the latter case. In both cases, the mass accretion rate is very small and varies little with orbital phase, which is consistent with the observed X-ray behaviour of Be/X-ray binaries with circular orbits (e.g. XTE J1543-568).

2005-01-01

437

SIMS imaging studies of the corrosion of alloy 800 and alloy 600 surfaces under secondary side boiler conditions  

Energy Technology Data Exchange (ETDEWEB)

The nickel-rich superalloys Alloy 600 and Alloy 800 have been corroded in mildly alkaline deuterated aqueous conditions typical of secondary coolant circuits in a nuclear power station. The oxide films and substrates of these alloys have been analysed by imaging SIMS depth profiling, which makes it possible to describe elemental distribution in all three dimensions. The measurement of the distribution of the secondary ions NiO[sup -], FeO[sup -] and CrO[sup -] appears useful for detailing the behaviour of nickel, iron and chromium within oxidized phases. The measurement of D[sup -] distribution outlines the extent of oxide hydration. For Alloy 800, evidence of sodium migration into the grain boundaries of the alloy substrate is found. For Alloy 600, no grain boundary sodium ingress can be identified under comparable corrosion conditions. (author).

1992-08-01

438

SIMS imaging studies of the corrosion of alloy 800 and alloy 600 surfaces under secondary side boiler conditions  

International Nuclear Information System (INIS)

The nickel-rich superalloys Alloy 600 and Alloy 800 have been corroded in mildly alkaline deuterated aqueous conditions typical of secondary coolant circuits in a nuclear power station. The oxide films and substrates of these alloys have been analysed by imaging SIMS depth profiling, which makes it possible to describe elemental distribution in all three dimensions. The measurement of the distribution of the secondary ions NiO"-, FeO"- and CrO"- appears useful for detailing the behaviour of nickel, iron and chromium within oxidized phases. The measurement of D"- distribution outlines the extent of oxide hydration. For Alloy 800, evidence of sodium migration into the grain boundaries of the alloy substrate is found. For Alloy 600, no grain boundary sodium ingress can be identified under comparable corrosion conditions. (author).

439

SAXS studies on added-salt species dependence of conformation of fully-charged poly(L-glutamate) in aqueous solutions  

Energy Technology Data Exchange (ETDEWEB)

The effect of counter-ion species on the local conformation of fully-charged poly(L-glutamate) in added-salt aqueous solutions were studied by small-angle X-ray scattering(SAXS). In the case of presence of monovalent counter-ion, the scattering behaviour could be explained by taking into consideration the excluded volume effect and intermolecular-interface interaction on the scattering function of wormlike chain. On the other hand, since SAXS profile of the solution in the presence of divalent counter-ion well fitted to the scattering function of dendrimer, it suggested that the conformation of polymer chain in such solution would be more compact conformation than that of presence of monovalent ion.

2010-10-01

440

Reversing flow catalytic converter for a natural gas/diesel dual fuel engine  

Energy Technology Data Exchange (ETDEWEB)

An experimental and modelling study was performed for a reverse flow catalytic converter attached to a natural gas/diesel dual fuel engine. The catalytic converter had a segmented ceramic monolith honeycomb substrate and a catalytic washcoat containing a predominantly palladium catalyst. A one-dimensional single channel model was used to simulate the operation of the converter. The kinetics of the CO and methane oxidation followed first-order behaviour. The activation energy for the oxidation of methane showed a change with temperature, dropping from a value of 129 to 35 kJ/mol at a temperature of 874 K. The reverse flow converter was able to achieve high reactor temperature under conditions of low inlet gas temperature, provided that the initial reactor temperature was sufficiently high. (author)

2001-07-01

441

Responses of the blister beetle Hycleus apicicornis to visual stimuli  

British Library Electronic Table of Contents (United Kingdom)

Insect attraction to host plants may be partly mediated by visual stimuli. In the present study, the responses of adult Hycleus apicicornis (Gur.) (Coleoptera: Meloidae) to plant models of different colours, different combinations of two colours, or three hues of blue of different shapes are compared. Single-colour models comprised the colours sky blue, bright green, yellow, red, white and black. Sky blue (reflecting light in the 440-500 nm region) is the most attractive, followed by white, which reflects light over a broader range (400-700 nm). On landing on sky blue targets, beetles exhibit feeding behaviour immediately. When different hues of blue (of different shapes) are compared, sky blue is preferred over turquoise, followed by dark blue, indicating that H. apicicornis is more attra...

2011-01-01

442

Reactive blending of poly(ethylene 2,6-naphthalate) and Vectra A  

British Library Electronic Table of Contents (United Kingdom)

In situ composites based on poly(ethylene 2,6-naphthalate) (PEN) and a thermotropic liquid crystal polymer (Vectra A950) were prepared by melt blending under different processing conditions. Thermal behaviour, mechanical and physical properties and morphology of the blends were investigated. The DSC analysis indicates that, as expected, Vectra enhances the crystallization process of PEN. Moreover, mechanical and thermal tests evidence the significant role of 20wt% Vectra on increasing the material performances; tensile properties, coupled with SEM, show that strength and modulus of PEN are significantly improved when Vectra domains are long and continuous fibrils. The overall results can be attributed to the compatibilisation of the system induced by the mixing conditions that affect the e...

2009-01-01

443

Radiative properties of a solar cavity receiver/reactor with quartz window  

British Library Electronic Table of Contents (United Kingdom)

An energy transfer and conversion model for high-temperature solar cavity receivers has been developed using the transport behaviour of solar radiation as described by the spectral radiative exchange factors. A Monte-Carlo ray-tracing method coupled with optical properties was adopted, to predict radiation characteristics of the solar collector system by calculating radiative exchange factors. A cavity receiver with a plano-convexo quartz window was proposed, based upon the directional characteristics of the focal flux and the redistribution effect of the quartz window. Parametric studies on the windowed receiver provided a more uniform flux distribution, higher efficiency and lower loss than the windowless receivers. The predicted results serve as a design reference for the solar receiver...

2011-01-01

444

Processing and characterization of chitosan microspheres to be used as templates for layer-by-layer assembly  

British Library Electronic Table of Contents (United Kingdom)

Chitosan (Ch) microspheres have been developed by precipitation method, cross-linked with glutaraldehyde and used as a template for layer-by-layer (LBL) deposition of two natural polyelectrolytes. Using a LBL methodology, Ch microspheres were alternately coated with hyaluronic acid (HA) and Ch under mild conditions. The roughness of the Ch-based crosslinked microspheres was characterized by atomic force microscopy (AFM). Morphological characterization was performed by environmental scanning electron microscopy (ESEM), scanning electron microscopy (SEM) and stereolight microscopy. The swelling behaviour of the microspheres demonstrated that the ones with more bilayers presented the highest water uptake and the uncoated cross-linked Ch microspheres showed the lowest uptake capability. Micros...

2010-01-01

445

Preparation and characterization of polyamide 6/polyethylene blend-clay nanocomposites in the presence of compatibilisers and stabilizing system  

British Library Electronic Table of Contents (United Kingdom)

Several compatibilising systems were added to high-density polyethylene (HDPE) and polyamide 6 (PA6) blends in the presence of an organically modified montmorillonite (OMM). All the blends were prepared by using a co-rotating twin-screw extruder and characterized by SEM, TEM and XRD analyses. In addition, the rheological behaviour and the mechanical properties - tensile and impact - were evaluated. The presence of OMM affects the dimensions of the polymeric phases in the blend but not their mutual adhesion, granted only by the compatibilisers. TEM, SEM and XRD analyses indicated that there is a strict correlation between the compatibilisation level and the final interlayer distance achieved by OMM. Even if some filled compatibilised blends showed a fairly good morphology - in terms of phas...

2010-01-01

446

Photodegradation of polypropylene/polystyrene blends: Styrene-butadiene-styrene compatibilisation effect  

British Library Electronic Table of Contents (United Kingdom)

The mutual influence between the PP/PS polymer blend components during UV photodegradation was studied. Polypropylene (PP) and polystyrene (PS) have different photodegradation mechanisms, due to the larger UV absorption of polystyrene and formation of more stable tertiary carbon radicals. To compare the stabilities the kinetics of carbonyl formation was measured in different blend compositions. The results show that polystyrene presented a faster carbonyl formation than polypropylene, while the blends display faster kinetics than the isolated components. The kinetics of carbonyl formation of the blends was a function of polypropylene content. This result is unexpected if one considers the behaviour of each component alone. The kinetics and mechanism of UV degradation can be only explained ...

2008-01-01

447

PVT-apparatus for measurements on gas/oil solutions up to 2000 bar and 440 K  

Energy Technology Data Exchange (ETDEWEB)

A high pressure piezometer is described with which pVT-measurements on solutions of gases in liquids like oils can be performed at pressures and temperatures up to 2000 bar and 440 K, respectively. The present investigations deal mainly with the system squalaneCO/sub 2/ at different mole fractions, but also with squalaneN/sub 2/. The high accuracy of the measurements reveals a pronounced structure of the pV-curves in dependence on temperature and mole fraction. At larger mole fractions is the unequivocal assignment of the phases ambiguous, and the representation of the experimental data in terms of an equation of state not possible for the whole pressure and temperature range. However, for solutions with lower mole fractions could be determined the saturation pressures and the isothermal compressibility in the unsaturated region. Furthermore, the molar excess volumes of the mixture have been calculated and the phase behaviour has been discussed briefly. (orig.)

1982-11-01

448

Optimized zinc electrode for the rechargeable zinc-air battery  

Energy Technology Data Exchange (ETDEWEB)

For the development of a long-lived, electrically rechargeable zinc-air battery the structure and wettability of pasted zinc electrodes were optimized. Pasted zinc electrodes containing 1 to 10% cellulose, but having almost the same nominal capacities, were prepared and tested in zinc/oxygen cells. The effect of discharge rate on cell voltage and delivered capacity, as well as the maximum power, were measured. Furthermore, cell charge-discharge behaviour and cycle life were examined. After different times of operation, the porosity and the pore size distribution of the pasted zinc electrodes were measured by means of mercury porosimetry. The life cycle and peak power drain capability of the Zn/oxygen battery could be substantially improved by the addition of 10 wt% cellulose to the pasted zinc electrode. (author)

1998-09-01

449

On the sensitivity of coastal quasigeostrophic edge wave interaction to bottom boundary characteristics: possible implications for eddy parameterizations  

CERN Document Server

The Eady problem of baroclinic instability as applicable to quasi-geostrophic oceanic flows with zero internal PV gradients is revisited by introducing a mild slope and Ekman pumping on the lower boundary. The solution behaviour is determined by the isopycnal slope relative to either the bottom slope or the ratio of Ekman depth to horizontal wavenumber. Attention is paid to the physical interpretation of the growing, decaying and stable disturbances, with emphasis on the intimate connection between the quasigeostrophic edge waves and Eady waves, and the role of the isopycnal slope for the stability properties as opposed to the bottom density gradient. The disturbance structure is found to be strongly influenced by the boundary conditions. For a sloping bottom boundary, the growth rate is enhanced for the most unstable waves if the isopycnals tilt in the same direction as the bottom, but in general non-standard boundary conditions tend to retard the growth of ...

2004-01-01

450

Nondestructive techniques for the control of conditioned radioactive wastes  

International Nuclear Information System (INIS)

The final product of the radwaste conditioning process must satisfy certain requirments and physico-chemical properties in order to assure its safe long-term behaviour. Of course, the foreseen quality assurance and quality control should be conducted by means of non-destructive techniques. This work presents an over-view of various applicable non-destructive methods of analysis, showing their fields of investigation in testing waste packages, together with some arising practical problems. The most promising methods, such as eddy current testing, ultrasonic testing, #gamma#-scanning, #gamma#-spectroscopy, neutron counting and computerized tomography, are treated more deeply and some applications are presented. Particular attention is devoted to the development of a device based on computerized tomography; its essential components are reported and some design problems are also discussed.

2005-09-01

451

Nomographs for the optimum solar pond driven LiBr/ZnBr sub 2 /CH sub 3 OH absorption-refrigeration system  

Energy Technology Data Exchange (ETDEWEB)

The paper presents a procedure for the calculation of an absorption-refrigeration plant that uses an LiBr/ZnBr{sub 2}/CH{sub 3}OH solution and is driven throughout the year by heat received from a solar pond. The calculations for the solar pond are based on a finite-difference solution of the transient heat conduction differential equation during the year, and the operation of the refrigeration unit is simulated by the use of functions describing the thermodynamic behaviour of the working medium. On the basis of the procedure devised, correlations and nomographs are developed that describe the seasonally optimum operation of the proposed composite system. The nomographs may be employed for a first estimation in the design of such systems. (Author).

1992-07-01

452

New [{sup 99m}Tc]-cytectrene amine compounds as specific brain imaging agents  

Energy Technology Data Exchange (ETDEWEB)

Lipophilic tertiary amines attached to cylcopentadienyl technetium-99m tricarbonyl (cytectrene) have been prepared with high radiochemical yield and purity. Biodistribution studies in mice showed that [{sup 99m}Tc]-cytectrenes, containing in their structure an N-methylpiperidine, were accumulated in the brain up to 2.8% of injected dose with high brain-to-blood ratios at 15 min p.i. They therefore indicate some potential as brain imaging agents. It has to be pointed out that the N-methylpiperidine ester showed similar biological behaviour as the keto derivatives. This indicates that the conversion to polar metabolite(s) via hydrolysis of the ester group - as described for [{sup 99m}Tc]-ECD -is not essential for brain retention. (Author).

1995-02-01

453

New ["9"9"mTc]-cytectrene amine compounds as specific brain imaging agents  

International Nuclear Information System (INIS)

Lipophilic tertiary amines attached to cylcopentadienyl technetium-99m tricarbonyl (cytectrene) have been prepared with high radiochemical yield and purity. Biodistribution studies in mice showed that ["9"9"mTc]-cytectrenes, containing in their structure an N-methylpiperidine, were accumulated in the brain up to 2.8% of injected dose with high brain-to-blood ratios at 15 min p.i. They therefore indicate some potential as brain imaging agents. It has to be pointed out that the N-methylpiperidine ester showed similar biological behaviour as the keto derivatives. This indicates that the conversion to polar metabolite(s) via hydrolysis of the ester group - as described for ["9"9"mTc]-ECD -is not essential for brain retention. (Author).

454

Neutron powder diffraction and solid-state deuterium NMR studies of Ca{sub 2}RuD{sub 6} and the stability of transition metal hexahydride salts  

Energy Technology Data Exchange (ETDEWEB)

The crystal structure of Ca{sub 2}RuD{sub 6} has been determined by neutron powder diffraction: space group Fm3m, K{sub 2}PtCl{sub 6} structure, as found for other hexahydride salts of group 8 metals with alkaline earth or lanthanide counter ions. No structural phase transition was observed between 340 K and 50 K. The deuterium nuclear quadrupole coupling constant, 54.7 kHz, leads to an ionic character of the Ru-D bond of 76%. The known trends in the behaviour of A{sub 2}MH{sub 6} salts are interpreted in terms of the ionization energies of the cation and the central metal atom.

2008-07-28

455

Neutron powder diffraction and solid-state deuterium NMR studies of Ca2RuD6 and the stability of transition metal hexahydride salts  

British Library Electronic Table of Contents (United Kingdom)

The crystal structure of Ca2RuD6 has been determined by neutron powder diffraction: space group Fm3m, K2PtCl6 structure, as found for other hexahydride salts of group 8 metals with alkaline earth or lanthanide counter ions. No structural phase transition was observed between 340K and 50K. The deuterium nuclear quadrupole coupling constant, 54.7kHz, leads to an ionic character of the Ru-D bond of 76%. The known trends in the behaviour of A2MH6 salts are interpreted in terms of the ionization energies of the cation and the central metal atom.

2008-01-01

456

Modelling of two-phase natural circulation in a WWER-plant: PMK experimental results  

International Nuclear Information System (INIS)

Experiments have been performed with the PMK integral-type facility, a model of WWER-440 type PWRs, to investigate two-phase natural circulation behaviour. The phenomena to be expected in this reactor type are different from those in PWRs with vertical steam generators mainly due to the loop seal in the hot leg and the horizontal layout of the steam generator heat transfer tubes. The experiments showed that the system is repressurized when the water level drops to the hot leg elevation due to the effect of the loop seal. Opening of the loop seal can be smooth, but may lead to oscillations depending on the power and the mass inventory. Natural circulation recovers after the hot leg loop seal is opened, but then decreases with further mass inventory decrease. (orig.).

457

Metal dusting behaviour of welded Ni-base alloys with different surface finish  

Energy Technology Data Exchange (ETDEWEB)

Welded Ni-base alloys and Alloy 800 were exposed under metal dusting conditions at 600 C and 650 C for up to 6000 hours. Alloy 800 was attacked very strongly already in the first days and Alloy 600 also rather soon and widespread, on both materials attack started mainly in the heat affected zone. Several surface states of Alloy 600: brushed, ground, sand-blasted and pickled were tried only grinding caused a modest delay and decrease of metal dusting attack. Generally the attack was less widespread but deeper at 650 C than at 600 C, also for Alloy 601 and 602. The latter alloys show minor, mainly local attack, but especially the welds are affected. TIG welding led to better resistance than hand-welding. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

2003-10-01

458

Mechanistic Investigations of Surface Modification of Carbon Black and Silica by Plasma Polymerisation  

British Library Electronic Table of Contents (United Kingdom)

Carbon black is widely used as an active filler in the rubber industry to improve the physical properties of rubber. The surface energy of carbon black is high compared to that of various elastomers like styrene?butadiene rubber (SBR), butadiene rubber (BR) and ethylene?propylene?diene rubber (EPDM). The work aims at reducing the surface energy of carbon black by modifying its surface for application especially in rubber blends. The present paper looks into the possibility of using plasma polymerisation of acetylene as a surface modification technique for carbon black in comparison with silica. Thermogravimetric analysis, wetting behaviour with various liquids of known surface tension and time of flight secondary ion mass spectrometry (ToF-SIMS) were used to characterise the carbon black b...

2008-01-01

459

Market based pollution abatement measures and creation of internal environmental diseconomies  

Energy Technology Data Exchange (ETDEWEB)

New market based approaches are becoming increasingly important as instruments of environmental policy. The two main market approaches, i.e., transferable pollution permits (experimented in America), and 'green' energy surcharges (European philosophy), are described and discussed. An analysis of information on their state of implementation shows that, in the case of the former method, the greatest sources of difficulty arise in the determination of acceptable ceiling levels of emissions, in the distribution of permits among the various polluting firms, and in the legality of granting rights to pollute. Instead, the European experience has evidenced that energy surcharges motivated by environmental policy cannot have an appreciable positive impact on consumers or the economic system in general unless they are accompanied by well defined measures geared towards the promotion or creation of alternative solutions such as to stimulate radical change in social ...

1991-09-01

460

Manufacturing of Austenitic Stainless Steel-Zirconia Composites by Infiltration  

British Library Electronic Table of Contents (United Kingdom)

Abstract Within the framework of the CRC 799 -TRIP-Matrix-Composites- at the TU Bergakademie Freiberg new composite materials consisting of TRIP steel and zirconium dioxide ceramics are designed in a powder route and a casting route. To manufacture faultless samples basic investigations of the feeding and infiltration behaviour within macro porous ceramics such as filters were needed. The effects of bottom pouring and top pouring were investigated as well as the effects of different preheating temperatures, contents of phosphorous in the steel and flow trough rates. Bottom pouring corrupts the feeding mainly of filters with high ppi (pores per inch). Top pouring improves the feeding, but generates inhomogeneous infiltration qualities, which can affected and enhanced by a increasing preheat...

2011-01-01

461

Magnetism of DyPd_2Si_2 and ErPd_2Si_2  

International Nuclear Information System (INIS)

Neutron diffraction and magnetometric measurements on polycrystalline samples of DyPd_2Si_2 and ErPd_2Si_2 were carried out in the temperature range from 2 to 293 K. Both compounds show tetragonal ThCr_2Si_2 type crystal structure and order at 12 K in a sine modulated magnetic structure with propagation vectors k=[0.609,0,0.155] and [0.575, 0, 0.083] respectively. The oscillatory character of magnetic order found in RPd_2Si_2 (R=Tb-Er) compounds suggests exchange interaction described by the RKKY model to be dominant, but the non-monotonic dependence of respective Neel temperatures on the number of f-electrons indicates the influence of a crystalline electric field (CEF) on the magnetic behaviour in this series. (orig.).

462

Magnetic and magnetostrictive properties of manganese substituted cobalt ferrite  

International Nuclear Information System (INIS)

The magnetic and magnetostrictive properties of polycrystalline Co1-xMnxFe2O4 (0 ? x ? 0.4) have been studied. Although the Curie temperature decreases continuously with increasing concentration of Mn, the magnetization remains high up to x = 0.3 and unexpectedly low coercivity is observed for this composition showing an unusual magnetostrictive behaviour. This composition shows a relatively larger magnetostriction at low fields. Moreover, the strain derivative which is the slope of the magnetostriction curve at low magnetic fields is almost doubled and the field at which maximum magnetostriction is observed is reduced to almost half for 30% of Mn substitution. The results show that x ? 0.3 in Co1-xMnxFe2O4 is an optimum composition with superior magnetostrictive properties for many applications.

2007-06-07

463

Lithium carbon batteries with solid polymer electrolyte; Accumulateur lithium carbone a electrolyte solide polymere  

Energy Technology Data Exchange (ETDEWEB)

The lithium carbon batteries studied in this paper use plasticized polymer electrolytes made with passive polymer matrix swollen by a liquid electrolyte with a high ionic conductivity (> 10{sup -3} S/cm at 25 deg. C). The polymers used to prepare the gels are polyacrylonitrile (PAN) and vinylidene poly-fluoride (PVdF). The electrochemical and physical properties of these materials are analyzed according to their composition. The behaviour of solid electrolytes with different materials of lithium ion insertion (graphite and LiNiO{sub 2}) are studied and compared to liquid electrolytes. The parameters taken into account are the reversible and irreversible capacities, the cycling performance and the admissible current densities. Finally, complete lithium ion batteries with gelled electrolytes were manufactured and tested. (J.S.) 2 refs.

1996-12-31

464

Jets and accretion processes in Active Galactic Nuclei further clues  

CERN Document Server

We present evidence in favour of a link between the luminosity radiatively dissipated in the central engine of radio-loud Active Galactic Nuclei and the kinetic power in their jets. This piece of evidence is based on the relation we find between the luminosity in broad emission lines and the kinetic power in pc-scale radio jets, for a sample of radio-loud quasars for which suitable data are available in the literature. We find that the ionizing luminosity and the kinetic one are of the same order of magnitude, suggesting that the processes responsible for them are somehow related. A strong magnetic field in equipartition with the radiation field could be responsible for regulating both processes. BL Lac objects seem to follow a similar behaviour, but with comparatively fainter broad line emission.

1996-01-01

465

Investigations for judging the working behaviour of components made of alloy 800 and alloy 617 under creep stress. Untersuchungen zur Beurteilung des Betriebsverhaltens kriechbeanspruchter Bauteile aus Alloy 800 und Alloy 617  

Energy Technology Data Exchange (ETDEWEB)

The program introduced here for determining and describing the multi-axial creep of pipes is based, on the one hand, on the results of the nuclear process heat prototype plant material program and, on the other hand, on the possible load conditions which arise for evaluating accidents or extreme working situations. The basis of a theoretical description of multi-axial creep is the invariant theory in which both the von Mises configuration change hypothesis and the Norton creep law are included. Combined tension and torsion are also considered in detail, the superimposition of cyclic stresses in the tensile threshold area is discussed and cases of partial relaxation are explained. Experimental results for the discussed loads are introduced, which have led to satisfactory agreement between theory and experiment. (orig./MM).

1987-01-01

466

Investigations for judging the working behaviour of components made of alloy 800 and alloy 617 under creep stress  

International Nuclear Information System (INIS)

The program introduced here for determining and describing the multi-axial creep of pipes is based, on the one hand, on the results of the nuclear process heat prototype plant material program and, on the other hand, on the possible load conditions which arise for evaluating accidents or extreme working situations. The basis of a theoretical description of multi-axial creep is the invariant theory in which both the von Mises configuration change hypothesis and the Norton creep law are included. Combined tension and torsion are also considered in detail, the superimposition of cyclic stresses in the tensile threshold area is discussed and cases of partial relaxation are explained. Experimental results for the discussed loads are introduced, which have led to satisfactory agreement between theory and experiment. (orig./MM).

1987-11-27

467

Influence of fluorine on the simulation of the transient enhanced diffusion of 15 keV BF_2"+ ion implantation into silicon  

International Nuclear Information System (INIS)

We have simulated the transient enhanced diffusion (TED) of boron fluoride (BF_2"+) implanted in crystalline and germanium amorphized silicon. Based on recently published models, the effect of fluorine on boron diffusion in silicon has been introduced and a modelling has been suggested. In order to simulate the boron experimental profiles, we have assumed that fluorine forms clusters involving interstitial boron which reduces the junction depth. Experimental results indicate that fluorine behaviour depends on amorphization energy. Moreover, even no germanium preamorphization is performed, silicon is still amorphized by fluorine species. Hence, BF_2"+ implantation leads to an amorphous/crystalline (a/c) interface near the surface. An improvement of published models is suggested taking into account fluorine effects. The simulations satisfactory reproduce the SIMS experimental profiles for a large scale of experimental conditions.

2002-01-01

468

Hydro cyclone. Dimensioning and operation; Hidrociclon. Dimensionado y operacion  

Energy Technology Data Exchange (ETDEWEB)

The hydro cyclone is a piece of equipment for separating and/or classifying solids/liquids with a wide variety of applications in different industrial sectors. This article describes the construction and operation of a hydro cyclone to verify the influence of the main size parameters and variables on its concentrating behaviour. The industrial-sized model which was built does not correspond exactly to the engineering designs. During operation, there was a load loss, which did not exceed 30 kPa, as a results of the fact that the suspension flow was unable to circulate with the original dimensions. However, when, for various reasons, the lower diameter was reduced, it proved possible to achieve an efficiency rate of over 95% in the concentration circuit. (Author) 23 refs.

2007-07-01

469

Hybrid Composites Made from Oil Palm Empty Fruit Bunches/Jute Fibres: Water Absorption, Thickness Swelling and Density Behaviours  

British Library Electronic Table of Contents (United Kingdom)

In this research, hybrid composite materials were prepared from combination of oil palm Empty fruit bunches (EFB) fibre and jute fibre as reinforcement, epoxy as polymer matrix. This study intended to investigate the effect of jute fiber hybridization and different layering pattern on the physical properties of oil palm EFB-Epoxy composites. Water absorption and thickness swelling test reveal that hybrid composite shows a moderate water absorption which is 11.20% for hybrid EFB/Jute/EFB composite and 6.08% for hybrid Jute/EFB/Jute composite. The thickness swelling and water absorption of the hybrid composites slightly increased as the layering pattern of hybrid composites changed. Hybrid composites are more water resistance and dimensional stable compare to the pure EFB composites. This is...

2011-01-01

470

High capacity orthorhombic LiMnO{sub 2} phases: role of piling up defects; Phases LiMnO{sub 2} orthorhombiques a haute capacite: role des defauts d`empilement  

Energy Technology Data Exchange (ETDEWEB)

The electrochemical performances of orthorhombic LiMnO{sub 2} compounds are analyzed in order to find a structural and/or morphological origin to the differences of electrochemical behaviours observed in compounds with different size of crystallites and different amounts of lattice defects. Energy capacity performances of 200 Ah/kg are reached for materials with crystallites of about 10{sup 7} Angstrom{sup 3} and with about 7% of defects, while energy capacities of only 80 Ah/kg are obtained for materials with ten times bigger crystallites. (J.S.) 3 refs.

1996-12-31

471

Graphite as negative electrode in Li-ion batteries; Le graphite comme electrode negative dans les accumulateurs Li-ion  

Energy Technology Data Exchange (ETDEWEB)

The last developments in lithium batteries design have demonstrated the advantages of graphite: competitive cost, flat output curve, high capacity thanks to the obtention of a final compound close to LiC{sub 6}, good behaviour during cycling and a high mass energy. However, these advantages are slightly tarnished by parasite secondary reactions during the evolution of the element. Two different cases are encountered: the formation of a passivation layer (loss of Li ions and formation of irreversible bounds) and the formation of a passivation layer with a reaction between graphite and the solvent (partial destruction of the graphite crystal lattice). In the first case, the theoretical graphite insertion capacity remains at 372 mAh/g while in the second case the insertion capacity is greatly reduced. Abstract only. (J.S.)

1996-12-31

472

Friction in ultra-thin conjunction of valve seals of pressurised metered dose inhalers  

British Library Electronic Table of Contents (United Kingdom)

In many drug dispensing devices, such as syringes and inhalers, an elatomeric gasket is used to prevent the formulation from leaking from the chamber. During device actuation, the seal is subjected to friction, which in turn causes its deformation and can cause unintentional leakage, thus dose variability. Additionally, friction of seal is responsible for a host of potential problems such undue effort required for actuation and potential wear. The mechanism of friction generation in the seal conjunction is complex, arising from adhesion of rubber in contact with the moving interface, viscous action of a thin film of fluid and deformation of seal asperities. Therefore, the first step in understanding the conjunctional behaviour of rubber seals is a fundamental study of mechanisms of frictio...

2010-01-01

473

Experimental investigation and modelling of heat capacity, heat of fusion and melting interval of rocks  

Energy Technology Data Exchange (ETDEWEB)

The heat capacity and heat of fusion were measured for a number of minerals using differential scanning calorimetry (DSC). The DSC measurements showed that the heat of fusion for the minerals is very low compared to the heat of fusion for pure crystalline phases reported elsewhere. A model for the melting behaviour of mineral materials in terms of melting interval, heat capacities and heat of fusion has been developed. The only model input is the chemical composition of the mineral material. The model was developed to be implemented in a detailed model of a cupola furnace, thus the focus for the development was not only precision but also to obtain a model that was continuous and differentiable. The model is based on several different submodels that each covers a part of the heating and melting of rocks. Each submodel is based on large amounts of empirical data. Comparison of the model and the DSC measurements showed reasonable agreement for the model to be used ...

2003-11-28

474

Experimental and analytical study of saturation current density of laser-doped phosphorus emitters for silicon solar cells  

British Library Electronic Table of Contents (United Kingdom)

Heavily doped emitters with low saturation current density are of particular interest for selective emitter solar cells. These emitters can be obtained by laser doping through the phosphosilicate glass layer formed after thermal diffusion from POCl3 gas. The experimental results show that in contrast to purely POCl3 furnace-diffused emitters, the saturation current density of laser-doped emitters does not increase linearly as sheet resistance decreases, but rather features two distinct regimes. In one of these regimes, the saturation current density is found to decrease as the sheet resistance decreases, reaching values lower than those of furnace emitters. This peculiar behaviour was explained by both qualitative analysis and numerical simulations.

2011-01-01

475

Evaluation of Meta scheduler Architectures and Task assignment Policies for High throughput Computing  

CERN Document Server

In this paper we present a model and simulator for many clusters of heterogeneous PCs belonging to a local network. These clusters are assumed to be connected to each other through a global network and each cluster is managed via a local scheduler which is shared by many users. We validate our simulator by comparing the experimental and analytical results of a M/M/4 queuing system. These studies indicate that the simulator is consistent. Next, we do the comparison with a real batch system and we obtain an average error of 10.5\\% for the response time and 12\\% for the makespan. We conclude that the simulator is realistic and well describes the behaviour of a large-scale system. Thus we can study the scheduling of our system called \\dirac in a high throughput context. We justify our decentralized, adaptive and opportunistic approach in comparison to a centralized approach in such a context.

2006-01-01

476

Epigenetic regulation of autosomal gene expression by sex chromosomes  

British Library Electronic Table of Contents (United Kingdom)

Males and females display differences in physiology, behaviour and susceptibility to many diseases. Genome-wide transcription profiling studies have uncovered large-scale sex differences in autosomal gene expression in somatic tissues that are thought to underlie such 'sexual dimorphisms'. Because males and females differ genetically mainly in their sex chromosome complement, most sex differences can be traced back to the X and Y chromosomes. Although sex hormones are usually considered the main architects of sexual dimorphisms, recent studies have demonstrated that sex chromosomes can also induce sex differences in somatic gene expression in the absence of hormonal differences. The recent discovery of epigenetic sex differences that are not hormone-induced brings us closer to understandin...

2011-01-01

477

Effect of weld heat input and creep strain on the elevated temperature and crack growth properties of austenitic steels  

International Nuclear Information System (INIS)

The potential material class for use at 600"0C and more, e.g. for steam turbines with improved thermal efficiency, are austenitic steels. Using these steels with welded joints, it is to be considered that, by superposition of weld residual stresses and service stresses, extensive creep strains - and in the worst case crack formation - can occur locally. To assess the influence of these effects on service behaviour, different material states of CrNi-steels and Incoloy 800 were investigated with respect to strength, ductility and, especially, to crack and creep crack growth in the temperature range around 600"0C. It is shown that creep embrittlement, not microstructural changes as effected by weld heat input, causes heat affected zone (HAZ)-reheat cracking. Creep embrittlement can be avoided by special design and fabrication rules. (orig.).

478

Effect of different formulations on tebuconazole residues in stone fruits  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND: The correlation between pesticide residue levels and formulation of an active substance is often not considered, even if it is reasonable to expect some differences arising from behaviour during dilution and spraying, from adhesion to plant and from degradation. An experimental study to investigate the magnitude of tebuconazole residues as a function of different tebuconazole formulated products was carried out in Italy. The fungicide was applied as wettable powder (WP) and water-dispersible granule (WG) formulations to peach, plum, apricot and nectarine orchards, on four different sites. The fruit samples gained from the field trials were quantitatively analysed by gas chromatography with a nitrogen phosphorus detector (GC/NPD) for tebuconazole residues. RESULTS: Tebuconazole ...

2009-01-01

479

Effect of Coating of Ammonium Perchlorate with Fluorocarbon on Ballistic and Sensitivity Properties of AP/Al/HTPB Propellant  

British Library Electronic Table of Contents (United Kingdom)

Fluorocarbon polymers are used to enhance thermal stability and electrostatic protection of composite propellant compositions. A precipitation technique has been developed to coat ammonium perchlorate (AP) using a copolymer of hexafluoropropylene and vinylidene fluoride (HFP-VF) with the help of solvent-counter solvent method. The coated AP has been used to prepare propellant compositions in different ratio based on hydroxyl terminated polybutadiene (HTPB), aluminium powder along with uncoated AP and studied for viscosity build-up and visco-elastic behaviour as well as mechanical, ballistic, thermal and sensitivity properties keeping 86% solid loading. The data on viscosity build-up indicate that as the percentage of viton coated AP increases end of mix viscosity and viscosity build-up inc...

2009-01-01

480

Dose dependence of semiconductor material conductivity as a means of high fluence dosimetry  

Energy Technology Data Exchange (ETDEWEB)

Dose dependences of conductivity at a temperature of 78 K for InSb and InAs single crystals under reactor fast neutron, 50 MeV proton and 80 MeV alpha particle irradiation up to fluence of 10{sup 17} cm{sup -2} are considered. Special attention is given to non-trivial, but little known semi-conductor characteristics in terms of {sigma}(F) dependence at large fluences, and also to the versatility of such dependence for all semiconductors. The behaviour of semiconductor materials conductivity dependence on fluence presented here may be used for semiconductor dosemeters characterisitic variation forecasting under large fluence measurements and in radiation emergency dosimetry. (author).

1996-12-31

481

Does the online channel pay? A comparison of online versus offline information search on physical store spend  

British Library Electronic Table of Contents (United Kingdom)

The Internet has transformed consumer behaviour, particularly the manner in which consumers search for information prior to making a purchase. However, we know relatively little about the relationship between consumer information search strategies prior to visiting a physical retail store and the amount of money spent on product purchases. This raises an important question for retailers; does the online channel pay? We test this notion in a study of 1275 consumers across the four retail categories of Clothing and Footwear, Beauty and Skincare, DIY Hardware, and Kitchen and Bathroom Renovations. We find that in all categories, except for Clothing and Footwear, consumers who used the Internet to search for product information prior to making a physical store purchase, spent more money when p...

2010-01-01

482

Dielectric and thermal characteristics of gel grown single crystals of ytterbium tartrate trihydrate  

British Library Electronic Table of Contents (United Kingdom)

Dielectric and thermal characteristics of gel grown single crystals of ytterbium tartrate trihydrate have been carried out. The dielectric constant has been measured as a function of frequency in the range 2?kHz?1?MHz and temperature range 30?300??C. The dielectric constant increases with temperature, attains a peak near 215??C, and then decreases as the temperature exceeds 215??C. The dielectric anomaly at 215??C is suggested to be due to phase transition brought about in the material. The dielectric behaviour of the material is correlated with the results on thermal analysis. Thermogravimetric and differential thermal analysis have been used to study the thermal characteristics of the material. The experimental results show that the material is thermally stable up to 200??C. The decompos...

2007-01-01

483

Development of engineering technology basis for pyrometallurgical reprocessing: development of transport technology and pyro-process equipments  

International Nuclear Information System (INIS)

Development of the engineering technology basis of pyrometallurgical reprocessing is a key issue for industrialization. For development of the transport technologies of molten salt and liquid cadmium at around 773 K, a salt transport test rig and a metal transport test rig were newly installed in an Ar glove box. Function of the salt transport test rig was confirmed with LiCl-KCl molten salt, and the transport behaviour of molten salt was found to follow that of water. The molten salt/liquid metal contactor for Ln/An separation was newly designed and installed. The test with a single-stage contactor was successful with simulated elements, and a three-stage contactor is now under development. A large-scale electro-refiner with a function to transport molten salt and liquid cadmium were newly designed, and to be installed for demonstration test with simulated materials. (authors)

2006-09-25

484

Design and characterization of a lamellar nanostructure in a low C steel  

British Library Electronic Table of Contents (United Kingdom)

A fully lamellar ferrite/cementite nanostructure was designed in a low C steel by using a specific thermal treatment. The strengthening of such microstructure has been investigated as a function of prestrain by rolling up to a deformation of 300%. As in usual pearlitic structure, its work-hardening shows no saturation and its elongation to fracture remains rather constant instead of decreasing drastically as conventional steels. The hardening by a similitude effect is thus not the privilege of pearlitic steels. Nevertheless, its lower initial work-hardening rate at low strain compared to an equivalent pearlitic steel and a lower hardening potential at high strain let us suspect major differences in the nature and the behaviour of ferrite channels in relation to the morphogenesis of the mic...

2011-01-01

485

Corrosion and scale processes and their inhibition in simulated cooling water systems by monosaccharides derivatives  

British Library Electronic Table of Contents (United Kingdom)

A study of the ordinary mild steel/cooling water interface, with and without inhibitor, was carried out using electrochemical impedance spectroscopy (EIS). EIS spectra in uninhibited medium reveal that a layer of corrosion and scale products is formed naturally and evolves with the immersion time. Monosaccharides derivatives were used as corrosion inhibitors. Most of them exhibit good behaviour against corrosion of ordinary steel in simulated water systems. Their inhibiting efficiency increases with concentration rise and depends on molecular structure especially -OH groups' position on two adjacent carbons and their number. In addition, the effect of MoO4^2^- on the corrosion inhibition in the presence of the best inhibitor was also studied by EIS. The addition of MoO4^2^- enhanced the in...

2009-01-01

486

Complexity of chaotic fields and standard model parameters  

CERN Document Server

In order to understand the parameters of the standard model of electroweak and strong interactions (coupling constants, masses, mixing angles) one needs to embed the standard model into some larger theory that accounts for the observed values. This means some additional sector is needed that fixes and stabilizes the values of the fundamental constants of nature. In these lecture notes we describe in nontechnical terms how such a sector can be constructed. Our additional sector is based on rapidly fluctuating scalar fields that, although completely deterministic, evolve in the strongest possible chaotic way and exhibit complex behaviour. These chaotic fields generate potentials for moduli fields, which ultimately fix the fundamental parameters. The chaotic dynamics can be physically interpreted in terms of vacuum fluctuations. These vacuum fluctuations are different from those of QED or QCD but coupled with the same moduli fields as QED and QCD are. The vacuum ...

2007-01-01

487

Characterisation and use of biomass fly ash in cement-based materials  

British Library Electronic Table of Contents (United Kingdom)

This paper presents results about the characterisation of the biomass fly ashes sourced from a thermal power plant and from a co-generation power plant located in Portugal, and the study of new cement formulations incorporated with the biomass fly ashes. The study includes a comparative analysis of the phase formation, setting and mechanical behaviour of the new cement-fly ash formulations based on these biomass fly ashes. Techniques such as X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), thermal gravimetric and differential thermal analysis (TG/DTA), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and environmental scanning electron spectroscopy (ESEM) were used to determine the structure and composition of the formulations. Fly ash F1 from the t...

2009-01-01

488

Business opportunities with international financial institutions  

Energy Technology Data Exchange (ETDEWEB)

The marketing strategy developed for use in international markets by the S. M. Group International of Longueuil, Quebec, a company with interest and well-developed expertise in the environmental and energy sector, was described. The strategy is designed to aid in the selection of countries or regions of interest, in determining the sector of activity to be emphasized, in selecting a local partner or local business representatives, and in making contact locally with the people responsible for the development banks in the target countries in an effort to create awareness of the company. The company also tries, wherever possible, to promote its services to local governmental agencies through the industrial cooperation program of CIDA. Since development banks have a very conservative behaviour, past performances and constant provision of high quality services are of prime importance.

1994-12-31

489

Bulk amorphous and nanocrystalline Al83Fe17 alloys prepared by consolidation of mechanically alloyed amorphous powder  

British Library Electronic Table of Contents (United Kingdom)

In the present work, bulk amorphous and nanocrystalline Al83Fe17 alloys were obtained by consolidation of mechanically alloyed powders. Mechanical alloying of Al-17% Fe powder mixture yielded powder with an amorphous structure. Thermal behaviour of the milling product was examined using differential scanning calorimetry. This investigation revealed that the amorphous phase crystallised above 380^oC. The amorphous powder was compacted under a pressure of 7.7GPa in different conditions: at 380^oC for 600s and at 1000^oC for 180s. Structural investigations of the bulk material revealed that the amorphous structure was retained after consolidation process applied at 380^oC. Compaction under high pressure at 1000^oC caused crystallisation of the amorphous phase and appearance of metastable nano...

2010-01-01

490

BMBF status seminar: Bodies of landfills. Vol. 1. Conference report; BMBF-Statusseminar: Deponiekoerper. Bd. 1. Tagungsband  

Energy Technology Data Exchange (ETDEWEB)

This conference report contains the lectures presented at the BMBF status seminar on the cooperative project ``Bodies of landfills``, which took place at Wuppertal on 25th and 26th April 1995. The cooperative project was started in autumn 1993 and studies the long-term behaviour of wastes deposited at landfills in general. Inorganic and municipal wastes are studied separately. (orig./SR) [Deutsch] Der vorliegende Tagungsband enthaelt die Vortraege des BMBF-Statusseminars zum Verbundvorhaben `Deponiekoerper` vom 25. und 26. April 1995 in Wuppertal. Das Verbundvorhaben `Deponiekoerper` wurde im Herbst 1993 begonnen und befasst sich ganz generell mit dem langfristigen Deponieverhalten von Abfaellen. Es ist unterteilt in die Untersuchung von anorganischen Abfaellen und von Siedlungsabfaellen. (orig./SR)

1995-12-31

491

Autonomous multi-sensor micro-system for measurement of ocean water salinity  

British Library Electronic Table of Contents (United Kingdom)

This paper describes the design, fabrication and application of a micro-fabricated salinity sensor system. The theoretical electrochemical behaviour is described using electrical equivalent diagrams and simple scaling properties are investigated analytically and numerically using finite element method (FEM). The chip design and fabrication is described and measurement results of two different electrode designs are presented. The 4mm Formula Not Shown 4mm multi-sensor allows for salinity determination with an accuracy of Formula Not Shown 0.5psu through determination of the electrical conductivity, temperature and pressure with accuracies of Formula Not Shown 0.6mS, Formula Not Shown 0.065 Formula Not Shown C and Formula Not Shown 0.05bar, respectively.

2008-01-01

492

Ar/sup +/ ion beam induced silicide formation mechanism at the Pf-Si interface  

Energy Technology Data Exchange (ETDEWEB)

Evaporated palladium films of 45 nm thickness on Si(111) were irradiated using 78 keV Ar/sup +/ ions with doses in the range of 1 x 10/sup 15/ to 1.5 x 10/sup 16/ cm/sup -2/ for the purpose of studying silicide formation. Rutherford backscattering analysis shows that intermixing has occurred across the Pd-Si interface at room temperature. The mixing behaviour increases with increasing dose of the bombarding ions, which agrees well with a theoretical model of isotropic cascade mixing for palladium, and radiation-enhanced diffusion associated with an interstitial mechanism for silicon.

1989-01-01

493

Application of alloy 800 in PWRs  

International Nuclear Information System (INIS)

Alloy 800 has been used by Siemens since 1968 and is now used by KWU for U-tubed steam generators in PWR's. The particular grade of alloy 800 that is used is within the ASTM-Specification B 163, but there have been modifications in composition to improve the corrosion resistance. First the permitted upper limit of carbon was reduced to 0.04% and was then further reduced to 0.03% and a stabilisation ratio of Ti : C >= 12 and Ti : C + N >= 8 was specified. The minimum permitted chromium and nickel levels were increased to 20% and 32% respectively. The maximum permitted levels of other elements or impurities were reduced. At the final fabrication stage peening with glass beads on the outer surface was specified to introduce a compressive stress to depth greater than that allowed for production flaws. An account is given of the behaviour of the alloy in service in four power plants already in operation, and future developments are discussed. (author).

494

Angular momentum dependence in 22 MeV alpha-particle elastic scattering by light nuclei  

International Nuclear Information System (INIS)

Elastic scattering of 22 MeV alpha particles by "2"3Na, sup(24-25-26)Mg, "2"7Al and "2"8Si has been measured between 24"0 and 174"0 lab. Partial angular distributions, from 120"0 to 174"0, were also measured at incident energies of 18.4 and 20.7 MeV for "2"4Mg, and 18.9 and 20.5 MeV for "2"8Si. The most striking feature of the data is the large angle behaviour: spin-zero nuclei display more pronounced backward oscillations and the cross section rises more steeply towards 180"0 for 4n nuclei than for the others. (Z.M.).

495

Analytical examination of the preignition processes within homogeneous mixtures of a gaseous fuel and air in a motored engine  

Energy Technology Data Exchange (ETDEWEB)

Examination is made of the main features of the physical and chemical preignition processes within homogeneous mixtures of air and gaseous fuels, such as propane, methane and hydrogen in a motored engine, while employing detailed chemical kinetics in a one zone analytical model. The changes in the compression temperature and pressure due to the admission of gaseous fuels, energy release during the preingition reactions and the contributions of heat transfer and residual gases to the preignition reaction activity were followed over a number of consecutive cycles until the occurrence of autoignition. Some of the observed differences in engine behaviour when operating on methane, propane and hydrogen were discussed with particular reference to the observed trends in dual fuel engine operation. Calculated results showed good agreement with some corresponding experimental trends. 14 refs., 9 figs.

1994-10-01

496

Analysis of the operating conditions influence on PEM fuel cell performances by means of a novel semi-empirical model  

British Library Electronic Table of Contents (United Kingdom)

The present paper concerns the development of a polymer electrolyte membrane (PEM) fuel cells model in order to analyse the behaviour of the cell varying its operating parameters such as temperature (70-120 ^oC), pressure (1-3 atm), relative humidity (35-100%) and CO content (0-200 ppm) in the feeding gas. The voltage output and the relative current of a generic PEM fuel cell has been predicted through a mathematical method based on semi-empirical correlations derived from the experimental data available in literature. The model has been implemented in a commercial process simulator (AspenPlus) and it has been validated by comparing the obtained results with further experimental data (not utilized for the model development). The comparison has underlined a good agreement with the experimen...

2011-01-01

497

Alloy 800: New stress rupture and creep data for pressurised components in high-temperature reactors  

International Nuclear Information System (INIS)

A new evaluation of the 1% time strain limit for creep strength and the isochronous stress/strain relationship was to be undertaken for the type 800 alloy, based on up to date experimental data. After the evaluation of the 1% time strain limit curves and time fracture curves of individual melts, multilinear regression analyses were made to clear up the relationship between parameters of the creep behaviour such as creep strength, 1% time strain limit and time fracture strain on the one hand and metallurgical parameters such as C, Ti, Al, Ni, Cr contents or grain size and type of manufacture, on the other hand. Based on the knowledge gained from these calculations, new limits were determined for HTR material specifications for variants of the 800 alloy of the Rk, NT, DE, and HT type. (orig./DG).

1988-10-06

498

A model-theory for Tachyons in two dimensions  

International Nuclear Information System (INIS)

The subject of Tachyons, even if still speculative, may deserve some attention for reasons that can be divided into a few categories, two of which are as follows: The larger scheme, to build up in order to incorporate space-like objects in the relativistic theories. These allow better understanding of many aspects of the ordinary relativistic physics, even if Tachyons would not exist in our cosmos as ''asymptotically free'' objects; superliminal classical objects can have a role in elementary particle interactions (perhaps even in astrophysics) and possible verification of the reproduction of quantum-like behaviour at a classical level when taking into account the possible existence of faster-than-light classical particles. This paper shows that Special Relativity - even without tachyons - can be given a form which describes both particles and anti-particles. This paper also is confined only to a ''model theory'' of Tachyons in two dimensions.

499

A Late Holocene explosive mafic eruption of Villarrica volcano, Southern Andes: The Chaimilla deposit  

British Library Electronic Table of Contents (United Kingdom)

Villarrica (Chile) is one of the most active volcanoes in South America having erupted about 60 times in the last 460years. Although its historical eruptive activity has been mainly effusive and weakly explosive, it had strong explosive behaviour in postglacial times. Chaimilla (<3.1ka) is one of the best exposed and widely dispersed pyroclastic deposits, related to both fall and flow activity. The deposit is dispersed over an area of 250km^2 and consists of 8 units (A-H) which were grouped into four sequences. Stratigraphic data suggest that the eruption had a relatively short duration and evolved from i) an Opening phase, dispersing ash, lapilli clasts, accretionary lapilli, blocks and bombs, to ii) a Pulsatory phase, originating a series of magmatic explosions, to iii) a Collapsing phas...

2011-01-01

500

5f electron localization-delocalization transition from UPd_3 to UPt_3  

International Nuclear Information System (INIS)

The electronic structures of URh_3, UPd_3, UPt_3 and UAu_3 are calculated with the self-interaction-corrected local-spin-density approximation. We find that only in URh_3 the f-electrons are fully delocalized. UPt_3 has one f-electron localized at each U site, whilst a localized f"2 configuration of the U-ion is found for UPd_3. It is predicted that upon application of pressure, UPd_3 will acquire the f"1 configuration and possibly exhibit heavy-fermion behaviour. We find that UAu_3 is characterized by the same mixed localized-delocalized f-electron manifold as UPd_3. (author)

2002-07-01