British Library Electronic Table of Contents (United Kingdom)

Epitaxial thin films of nanotwinned face-centered cubic metals such as Cu possess an unprecedented combination of high hardness and high electrical conductivity due to the unique structure of nanometer-spaced coherent twin boundaries. Recent studies of in-situ nanoindentation in a transmission electron microscope have provided new insights on the deformation behavior of nanotwins that are reviewed here. In particular, two unit processes are highlighted: first, stress-induced migration of ?3 {112} incoherent twin boundary that leads to de-twinning of nanotwins; second, twinning dislocation can be multiplied at ?3 {111} coherent twin boundary.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

The grain size dependence of the tensile properties and the deformation mechanisms responsible for those properties are examined for Mg alloy, AZ31B, sheet. Specifically, the Hall-Petch effect and strain anisotropy (r-value) are characterized experimentally, and interpreted using polycrystal plasticity modeling. {1 0 . 2} extension twins, {1 0 . 1} contraction twins, and so-called 'double-twins' are observed via microscopy and diffraction-based techniques, and the amount of twinning is found to increase with increasing grain size. For the sheet texture and tensile loading condition examined, {1 0 . 2} extension twinning is not expected, yet the polycrystal plasticity model predicts the observed behavior, including this 'anomalous' tensile twinning. The analysis shows that the Hall-Petch strength dependence, of the polycrystal as a whole, is primarily determined ...

Energy Technology Data Exchange (ETDEWEB)

The microstructural development inside the stress induced martensite (SIM) variants in Ti-Ni-Nb alloy with various degrees of deformation have been revealed by electron microscopic observations. The orientation relationship between the SIM and the parent phase has been found: [1{bar 1}0]{sub M}{parallel}[11{bar 1}]{sub B2}, (001){sub M} 5{degree} away from (101){sub B2}. The lattice invariant shear of the SIM variants at the slightly deformed stage is dominantly (11{bar 1}) Type I twin. Besides the ordinary slip, the adjustment and development of the internal secondary twinning from (11{bar 1}) Type I twin to {l_angle}011{r_angle} Type II/ or (011) Type I twin, (001)compound twin and (111) Type I twin happen concurrently or in combination inside the SIM variants with the further deformation. The corresponding deformation mechanisms include stress induced ...

International Nuclear Information System (INIS)

A study was performed to investigate the degree of similarities and differences in components of craniofacial complex between Korean twins and normal children by lateral cephalometric analysis. Dimensions of S-N, S-Ba, N-Ba, Go-Me, Ar-Go and Ar-Me were plotted against linear measurement and angles of N-S-Ba and gonial against angular measurement in twins and control groups. The lateral cephalograms of twin were composed of 88 twins aged from 7 to 12:44 males aged 10.65 and 44 females aged 9. 55, while those of 50 normalities were composed of 25 male and 25 female aged 10.9 respectively. In order to analyze growth proportion and sexual differences, twins were divided into 3 groups according to two year age intervals and the author compared male with female in 3 groups. For the purpose of observing similarities and differences in twins and normalities by sex, ...

International Nuclear Information System (INIS)

Phase and structural transformations in a multicomponent (5.05 mas.% Mo-4.95V-3.00Cr-3.05Al) metastable #beta#-titanium alloy on aging after plastic deformation are studied using methods of electron microscopy and X-ray diffraction analysis. The alloy is deformed by twinning in a #left brace#332#right brace# system, and even at initial stages the formation of a twin skeleton takes place in the structure, on further loading the deformation of the skeleton is by secondary twinning resulting in a high plasticity of the alloy. On annealing mechanical twins transform into #alpha#-phase - a ductile twin skeleton is replaced by a rigid skeleton of #alpha#-phase plates. The aging enhances the yield strength of the alloy but decreases sharply its plasticity

Science.gov (United States)

Models are proposed which explain the mechanism of action on a molecular level for the initiation of cancer by electrons or alpha particles. (ACR)

Energy Technology Data Exchange (ETDEWEB)

The development of a twinned microstructure in hexagonal close-packed rolled magnesium compressed in the in-plane direction has been monitored in situ with neutron diffraction. The continuous conversion of the parent to daughter microstructure is tracked through the variation of diffraction peak intensities corresponding to each. Approximately 80% of the parent microstructure twins by 8% compression. Elastic lattice strain measurements indicate that the stress in the newly formed twins (daughters) is relaxed relative to the stress field in the surrounding matrix. However, since the daughters are in a plastically 'hard' deformation orientation, they quickly accumulate elastic strain as surrounding grains deform plastically. Polycrystal modeling of the deformation process provides insight about the crystallographic deformation mechanism involved.

British Library Electronic Table of Contents (United Kingdom)

Background Previous reports in adults have suggested that the effects experienced after cannabis use can be described in terms of positive and negative subtypes that are heritable and are associated with abuse and dependence. This study extends existing research by inclusion of adolescents and young adults in an offspring of twins design which makes it possible to take into account genetic and environmental risks for substance use disorder. Methods Data were collected from 725 twin members of the Vietnam Era Twin Registry, 839 of their 12-32 year old biological offspring and 427 mothers. Offspring who had ever used cannabis (n=464) were asked the degree to which they typically experienced 13 subjective effects shortly after using cannabis. Latent class analysis (LCA) was used to derive sub...

British Library Electronic Table of Contents (United Kingdom)

Smoothed Particle Hydrodynamics (SPH) is a Lagrangian, particle-based method that is well suited to industrial mixing simulations. Mass transport is simply the motion of the particles, and its grid-free nature means that it can easily accommodate complicated geometries involving moving parts and sharp corners. This article describes 2D SPH simulations of a Twin Cam mixer and compares the results against experimental data and results from two published finite element method (FEM) simulations. To analyze the mixing processes in the Twin Cam mixer, we present a method for calculating the Finite-Time Lyapunov Exponent (FTLE) using SPH particle data. The FTLEs can be used to locate the unstable and stable manifolds in the flow and indicate where mixing is either promoted or inhibited in the flo...

Science.gov (United States)

The progress made during the first two years of a program to study the migration of grain boundaries in ceramic oxides is reported. The principal results of the program are concerned with the structure of grain boundaries in ..cap alpha..-Al/sub 2/O/sub 3/, although important new information has also been obtained on grain boundaries in spinels and both germanlum and silicon. Attention is focused on the basal twin boundary in ..cap alpha..-Al/sub 2/O/sub 3/ which had been identified as a model interface in early work. A series of new grain boundaries exemplified by the (11anti23) twin are also discussed briefly as is the rhombohedral twin interface. Earlier results on the first-order (..sigma..=3) twin in spinel have been extended with the development of models for the computer-simulation of high-resolution TEM images of these interfaces. A study of low-angle grain boundaries in spinel is giving new ...

Energy Technology Data Exchange (ETDEWEB)

To test the assumption underlying every morphometric twin study that the brains of monozygotic twins are almost identical. Methods: High resolution MRI of the neurocranium of 26 monozygotic twin pairs were acquired and the volumes of 36 cerebral structures were measured. The same twins served as control group after rear-ranging them into non-related pairs of same sex and matching them for age, body height and body weight. Results: For most of the examined structures the correlations within the twins were significant (R = 0,97-0,59). Except for total forebrain volume the controls showed no significant similarity. Conclusions: For almost every measured cerebral structure the assumption, that significant similarities exist between healthy monozygotic twins is correct. Therefore discordant monozygotic twins represent an excellent sample when ...

British Library Electronic Table of Contents (United Kingdom)

Previous family and twin studies have indicated that Graves' disease has a heritable component. Family studies have also shown that some autoimmune disease cluster in families and genetic studies have been able to show shared susceptibility genes. In the present nation-wide study we describe familial risk for Graves' disease among parents and offspring, singleton siblings, twins and spouses with regard to age of onset, gender and number and type of affected family members. Additionally familial association of Graves' disease with any of 33 other autoimmune and related conditions was analyzed. The Swedish Multigeneration Register on 0-75-year-old subjects was linked to the Hospital Discharge Register from years 1987-2007. Standardized incidence ratios (SIRs) were calculated for individuals ...

Energy Technology Data Exchange (ETDEWEB)

As a continuation of our previous study, further experiments were performed on Li[sub 3]PO[sub 4]-Li[sub 2]S-SiS[sub 2] lithium ion conductive glass. In the present study, we employed a twin roller for quenching process instead of liquid nitrogen. We found that the glass forming region expands by twin roller technique and conductivity up to 1.5x10[sup -3] S/cm was achieved. Structural analysis on the glass revealed that Li[sub 3]PO[sub 4] doping changes the glass structure of Li[sub 2]S-SiS[sub 2], thereby enhancing the electrical conductivity

Energy Technology Data Exchange (ETDEWEB)

Large single crystals of PETN, RDX, and TNT can be grown easily from evaporating ethyl acetate solutions. The crystals all share a similar type of defect that may not be commonly recognized. The defect generates conical faces ideally mosaic crystals, and may account for the polymorphs'' of TNT and detonator grades of PETN. TATB crystals manufactured by the amination of trichlorotrinitrobenzene in dry toluene entrain two forms of ammonium chloride. One of these forms causes worm holes'' in the TATB crystals that may be the reason for its unusually low failure diameters. Strained HMX crystals form mechanical twins that can spontaneously revert back to the untwinned form when the straining force is removed. Large strains or temperatures above 100[degrees]C lock in the mechanical twins.

British Library Electronic Table of Contents (United Kingdom)

The grain morphology developed during solidification of an Al-4.5% Cu alloy is represented generally by columnar or equiaxed dendrites. Twinned feathery grains are found in the structure formed under certain heat and flow conditions during solidification. In this work, these conditions were achieved during solidification in a cavity under forced flow. Feathery grain formation is studied by means of fluid dynamics simulations with solidification included and by experiments. In order to determine the crystallographic orientation of feathery grains, electron backscattered diffraction measurements were performed. The growth features of feathery grains were analyzed by observations made normal and parallel to the growth direction. Some correlations between twinned feathery morphology, flow and ...

CERN Document Server

The Large Hadron Collider (LHC) will be equipped with several thousands of superconducting corrector magnets. Among the largest ones are the superconducting trim quadrupoles (MQTL). These twin-aperture magnets with a total mass of up to 1700 kg have a nominal gradient of 129 T/m at 1.9 K and a magnetic length of 1.3 m. Sixty MQTL are required for the LHC, 36 operating at 1.9 K in and 24 operating at 4.5 K. The paper describes the design features, and reports the measured quench performance and magnetic field quality of the production magnets. The MQTL magnet production is shared between CERN and industry. This sharing is simplified due to the modular construction, common to all twin-aperture correctors.

Science.gov (United States)

Rectangular stainless steel (SS) archwires were coupled with four SS bracket designs: Mini Diamond Twin, which was a conventional twin bracket; VersaT, which had bumps along the slot floor and rounded slot walls; Shoulder, which had bosses outside the tie-wings to lift the ligation off the archwire; and Synergy, which had bosses between the outer and inner tie-wings, bumps along the slot floor, and rounded slot walls. For all designs, the values of resistance to sliding (RS) were measured at five normal forces and 32 second-order angulations in the dry and wet (saliva) states. RS values at these same angles and states were also measured for the following: Mini Diamond Twin brackets ligated with rings and SS ligature wires; VersaT brackets ligated with rings; Shoulder brackets ligated with rings in a figure-8 and a figure-O around the tie-wings; and Synergy brackets ligated with rings around the outer tie-wings and around ...

Energy Technology Data Exchange (ETDEWEB)

This Phase IV Remedial Design/Remedial Action Work Plan addresses the remediation of areas with the potential for UXO at the Idaho National Laboratory. These areas include portions of the Naval Proving Ground, the Arco High-Altitude Bombing Range, and the Twin Buttes Bombing Range. Five areas within the Naval Proving Ground that are known to contain UXO include the Naval Ordnance Disposal Area, the Mass Detonation Area, the Experimental Field Station, The Rail Car Explosion Area, and the Land Mine Fuze Burn Area. The Phase IV remedial action will be concentrated in these five areas. For other areas, such as the Arco High-Altitude Bombing Range and the Twin Buttes Bombing Range, ordnance has largely consisted of sand-filled practice bombs that do not pose an explosion risk. Ordnance encountered in these areas will be addressed under the Phase I Operations and Maintenance Plan that allows for the recovery and disposal of ordnance that poses an ...

Energy Technology Data Exchange (ETDEWEB)

In the last few years the supercharging of Otto-cycle-engines has regained popularity, as demonstrated by a number of series-production engines. After listing the aims to be met by a modern supercharger the paper describes the technical status of mass-produced or close to production superchargers. This is followed by a comparative evaluation of the systems, enabling the reader to select possible solutions for a projected supercharger-engine-system by means of a comparison chart. The paper is concluded by a list of possible directions for further development and additional potential for twin-screw superchargers. (orig.) [German] In neuerer Zeit hat die Aufladung von Ottomotoren wieder ein verstaerktes Interesse gefunden, das sich auch in einer Anzahl serienmaessig gefertigter aufgeladener Motortypen wiederspiegelt. Der vorliegende Beitrag beschreibt, nach einer Darstellung der Anforderungen an ein modernes Aufladegeraet, den Stand der Technik bei serienmaessigen ...

British Library Electronic Table of Contents (United Kingdom)

This study examined the relationship between the 1997 UPE policy and regional educational and poverty inequality and its impact on lifelong learning through a one-year field based critical ethnography in Uganda, between June 2007 and May 2008. It drew on the Government's assumption that through UPE the twin goals of the universalisation of primary education and lifelong learning would be attained. This led to the concentration of resources away from higher education, secondary education, and lifelong learning to primary education. This 'UPE centric' approach ignored the precarious situation of the large number of illiterate children, youths and adults who have never accessed UPE or dropped out without attaining literacy and numeracy skills. This paper will clarify the relationship between ...

British Library Electronic Table of Contents (United Kingdom)

It is necessary to remove chlorine efficiently from municipal waste plastics (MWP) that contain polyvinyl chloride (PVC) and other plastics containing chlorine. In this article we consider thermal degradation liquefaction technology. In Japan, the chlorine content of reclamation oil products must be kept below 100 ppm owing to the quality standard for pyrolysis oil. Liquefaction dechlorination technology for MWP is still an important issue to study. The twin-screw extruder that has been developed as dechlorination technology for blast furnaces and coke ovens has a shorter residence time for dechlorination than other dechlorination technologies. In this article, we used a single-screw extruder for the dechlorination process because it also has a short residence time. Experiments on the dech...

British Library Electronic Table of Contents (United Kingdom)

This work deals with a new route to modify polymer blend morphology in order to improve the porosity of gas diffusion layers (GDLs) for proton exchange membrane fuel cells (PEMFCs). First, electrically conductive polymer-based blends were carefully formulated using a twin-screw extrusion process. Blend electrical conductivity was ensured by the addition of high specific surface area carbon black and synthetic graphite flakes. Final GDL porosity, in particular its macroporosity, was generated by melt blending polyamide 11 (PA11) matrix with polystyrene (PS) followed by PS extraction with tetrahydrofuran (THF) solvent at room temperature. In order to improve GDL porosity by the optimisation of PS dispersion in the PA11 matrix, PA11/PS blends were compatibilised by the addition of 2 wt.-% of ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Preparation of antibacterial alginate films incorporating extruded white ginseng (EWG) extracts was attempted. The antibacterial effect of EWG extract on six selected food pathogenic bacteria was compared with the effect of red ginseng (RG) and white ginseng (WG) extracts. The EWG was processed in a twin-screw extruder with feed moisture of 20% and barrel temperature of 115 and 130C. The data obtained by agar diffusion assay demonstrated that the film containing 1-g/mL of EWG at barrel temperatures of 115 (EWG-115) and 130C (EWG-130) exhibited stronger antibacterial activity against the four strains of bacteria than the other extracts RG and WG. All films sampled showed reduction in bacteria cell counts (log cycle) compared with the control. After 24-h of incubation, Pseudomonas a...

Energy Technology Data Exchange (ETDEWEB)

The microstructure of the layers produced by plasma nitriding austenitic stainless steel at different treatment temperatures (400 and 500 C) were studied by transmission electron microscopy (TEM) together with X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the microstructures were composed of 'expanded austenite' ({gamma}{sub N}) and {alpha}(ferrite)+CrN following plasma nitriding at lower and higher treatment temperatures, respectively. The former contains stacking faults and deformed twin substructures, while the latter is made up of colonies displaying a lamellar structure. Kurdjumov-Sachs or Nishiyama-Wassermann orientation relationships between the {alpha} and CrN layer were observed. (orig.)

International Nuclear Information System (INIS)

The microstructure of commercial rolled magnesium alloy AZ31B (nominal composition Mg-3Al-0.9Zn-0.15Mn in wt.%) was investigated with the help of light microscopy, electron backscatter diffraction (EBSD) and X-ray diffraction technique after annealing in the temperature range from room temperature (RT) to 400 deg. C. Tensile tests at RT were performed to show the influence of the microstructure on mechanical properties. Static recrystallization (SRX) was observed during annealing of as-received alloy at and above 150 deg. C. Twins play an important role during SRX and serve as nucleation sites and preferred paths for growth of grains. The strong basal texture caused by rolling was weakened by SRX. Significant differences in the stress strain curves were observed for as-received and annealed specimens.

Energy Technology Data Exchange (ETDEWEB)

This Field Sampling Plan outlines the collection and analysis of samples in support of Phase IV of the Waste Area Group 10, Operable Units 6-05 and 10-04 remedial action. Phase IV addresses the remedial actions to areas with the potential for unexploded ordnance at the Idaho National Laboratory Site. These areas include portions of the Naval Proving Ground, the Arco High-Altitude Bombing Range, and the Twin Buttes Bombing Range. The remedial action consists of removal and disposal of ordnance by high-order detonation, followed by sampling to determine the extent, if any, of soil that might have been contaminated by the detonation activities associated with the disposal of ordnance during the Phase IV activities and explosives during the Phase II activities.

Energy Technology Data Exchange (ETDEWEB)

The relativistic time dilation is reviewed in a cosmological context. We show that a clock or twin paradox does not arise if cosmic time is properly taken into account. The receding galaxy background provides a unique frame of reference, and the proper times of geodesic as well as accelerated observers can be linked to the universal cosmic time parameter. This suggests to compare the proper time differentials of the respective observers by determining their state of motion in the galaxy grid. In this way, each observer can figure out whether his proper time is dilated or contracted relative to any other. In particular one can come to unambiguous conclusions on the aging of uniformly moving observers, without reference to asymmetries in measurement procedures or accelerations they may have undergone.

International Nuclear Information System (INIS)

Dosimetry is evaluated for live-line workers exposed to 50 Hz non-uniform magnetic fields from typical high-voltage transmission lines in the United Kingdom. The configurations involve twin-, triple- and quadruple-conductor transmission line bundles. Scenarios include three worker postures for the twin and triple bundles, and four postures for the quadruple bundle. The postures are selected to simulate worst case scenarios representative of work practices and result in highest values of dosimetric measures in critical organs. Only single-phase bundles are considered, as adjacent bundles of differing phase result only in a small reduction of the dosimetric measures. Reported data include various measures of the electric field and current density induced in tissues, as well as of the current density averaged over 1 cm"2 areas normal to the current flow. A value of this latter quantity of 10 mA m"-"2 is suggested as a threshold for neural tissue ...

Energy Technology Data Exchange (ETDEWEB)

This paper introduces recent instances of polymerizers for highly viscous liquid needed in the field of synthetic resin and synthetic fiber. A horizontal twin-shaft type polymerizer has two horizontally rotating shafts with stirring blades of spectacle-shaped type, which are arranged at a 90 [degree] phase difference. As they rotate, they scrape highly viscous liquid sticking to the surface inside the polymerizer and on the rotating shafts. This polymerizer is capable of processing highly viscous liquid up to about 2000 Pa[center dot]s. A lattice-type twisting blade polymerizer is a vertical-type reactor and features a special stirring blade capable of stirring highly viscous liquid up to 5000 Pa[center dot]s This polymerizer has no central rotating shaft so that highly viscous liquid does not stick on it. A sloped blade-type thin-film evaporator has spiral blades in the longitudinal direction of the rotor. Process liquid pushed to the inner wall of the vessel by ...

Energy Technology Data Exchange (ETDEWEB)

ANCAP (Government's Oil Company of Uruguay) owns a 4000 DWT oil coastal tanker which is mainly used for oil transport in the River Plate, Uruguay and Parana rivers. Availability of the ship is critical because of shortage of available vessels in the region. Full maximum draught of the vessel is 4m , so it can navigate in very shallow waters as it is the case of some places in the Uruguay and Parana rivers. Although the ship was built in 1979, it is a complete double hull, powered by two twin main engines and propellers. Since 1994, several changes in maintenance management have been introduced, in order to increase the availability, thus increasing the total oil volume yearly transported. These changes affected several maintenance items and they also included a modification in the design of part of the cargo tank floors of the ship. As a result of these changes, an increase of 60% of the oil derivatives volume transported yearly was achieved. In this ...

Energy Technology Data Exchange (ETDEWEB)

As need for development of marginal and deepwater oil fields grows, demand increases for floating production vessels (FPVs) such as floating production, storage and offloading (FPSO) units; spread-moored production semi-submersibles; and turret-moored production vessels. The FPV may be purpose-built; or an existing vessel such as an exploration drilling semi-sub or ship-shape vessel may be modified to suit the purpose. In either case, requirements for tensioning systems for the mooring lines on the FPV are quite unique, and are not without the potential for problems when traditional chain windlasses or wire rope systems are employed. This two-part article discusses the range of available technologies and systems for tensioning mooring lines on FPVs. It examines problems of size, weight and safety associated with some available designs; and it considers in detail a specific family of new units. Part 1, presented here, discusses the FPV market, worldwide potential locations and different ...

DEFF Research Database (Denmark)

Repetitive hydatidiform mole was observed in four pregnancies. The pregnancies presented with heavy bleeding and vomiting, but the post-evacuation courses were uncomplicated, with rapid regression of serum hCG levels. Cytogenetic investigations, analyses of restriction fragment length polymorphisms, and flow cytometry in three pregnancies were consistent with diploid, biparental conception as the origin of fetal tissue and molar and nonmolar villi. In one pregnancy, the analyses of cytogenetic markers suggested the coexistence of two different cell lines of dizygotic, biparental origin, whereas DNA analysis was consistent with a single conception. With incomplete genetic information, a hydatidiform mole with coexistent normal fetus is generally considered to result from dizygous twinning comprising an androgenetic complete mole and a normal conception. In the present gestations, the results based on several techniques applied on numerous samples from different ...

Energy Technology Data Exchange (ETDEWEB)

The deformation behavior and structure changes of magnesium alloy AZ31 were studied in compression at temperatures ranging from 523 K to 673 K and at a strain rate of 3 x 10{sup -3} s{sup -1}. They depend sensitively on deformation temperature. At high temperatures, grain fragmentation takes place due to frequent formation of kink bands initially at corrugated grain boundaries and then in grain interiors, followed by full development of new grains in high strain. At lower temperatures, in contrast, twinning takes place in rather coarse grains and kink bands are formed mainly in finer original ones in low strain. It is concluded that new grain evolution can be controlled by a deformation-induced continuous reaction resulting in grain fragmentation by kink bands, i.e. continuous dynamic recrystallization (cDRX). The latter is discussed comparing with conventional, i.e. discontinuous, DRX. (orig.)

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the work on high field superconducting materials and processes performed at the Materials and Molecular Research Division of the Lawrence Berkeley Laboratory. Two major interrelated focal points characterize this research. One was the decision to restrict the effort to A-15 compounds because of their superior critical temperatures and critical fields. The inherent brittleness of these compounds along with the requirement for a filamentary morphology led to the second focal point: a heavy reliance on a powder approach for the fabrication of superconducting tapes and wires. There have been exceptions to the use of powder techniques where special circumstances such as the nature of a particular alloy system suggested on alternative approach. The quench-age technique described herein is an example of a non-powder approach. Here the niobium-aluminum system is involved and the methodology is based on the fact that in a certain composition range a solid solution of ...

Energy Technology Data Exchange (ETDEWEB)

The use of a non-dedicated GPS receiver system for attitude determination was assessed in airborne mode through a test conducted at Sandia National Laboratories. Four independent NovAtel GPSCard{trademark} receivers were installed in Sandia`s Twin Engine Otter with two antennas mounted on the fuselage and two on the wing tips at separations of 6 to 18 m. A strapdown INS was also on board the aircraft in order to provide an independent attitude reference at rates between 4 and 10 Hz. During the multi-day test, GPS measurements were recorded between 1 and 10 Hz. Carrier phase measurements were post-processed using a double difference approach developed at The University of Calgary in which integer ambiguities were resolved in seconds using the known antenna separations as constraints. The tracking capability of the system is demonstrated under dynamics consisting of roll and pitch angles up to 45 and 12 degrees, respectively. Comparisons between the GPS and INS ...

Energy Technology Data Exchange (ETDEWEB)

Attention deficit disorder (ADHD) is a complex biobehavioral phenotype which affects up to 8% of the general population and often impairs social, academic, and job performance. Its origins are heterogeneous, but a significant genetic component is suggested by family and twin studies. The murine strain, coloboma, displays a spontaneously hyperactive phenotype that is responsive to dextroamphetamine and has been proposed as a genetic model for ADHD. Coloboma is a semi-dominant mutation that is caused by a hemizygous deletion of the SNAP-25 and other genes on mouse chromosome 2q. To test the possibility that the human homolog of the mouse coloboma gene(s) could be responsible for ADHD, we have carried out linkage studies with polymorphic markers in the region syntenic to coloboma (20p11-p12). Five families in which the pattern of inheritance of ADHD appears to be autosomal dominant were studied. Segregation analysis of the traits studied suggested that the best ...

Science.gov (United States)

The twin-cities of El Paso and Juarez share the water resources of the Hueco Bolson aquifer and overlying Rio Grande aquifer. Both aquifers span the international border between Mexico and the United States. Salinity in the Rio Grande aquifer varies widely, some parts of the shallow aquifer containing less than 1,000 mg/L total dissolved solids (TDS), other parts of the aquifer exceeding 5,000 mg/L TDS. One sizable part of the "Lower Valley" area, approximately 45 km below El Paso contains very dilute water near the outer edge of the floodplain. Historically it had been thought that the dilute waters in this location were derived from recharge from arroyos that drained proximal parts of the Hueco Bolson. Instead, our hydrogen and oxygen isotope data and carbon-14 data indicate that these dilute waters were derived from pre-dam infiltration of the Rio Grande. Relatively light and slightly evaporated pre-dam waters (-11.5 del O18) at the arroyos are also ...

Science.gov (United States)

Evidence from twin, adoption, and family studies suggests that there is strong aggregation of suicidal behaviors in some families. By comparison, the role of social modeling through peers has yet to be convincingly established. This paper uses data from four large studies (the WHO/EURO Multicentre Study on Suicidal Behaviour, the WHO/SUPRE-MISS, the CASE study, and the Queensland Suicide Register) to compare the effects of exposure to fatal and nonfatal suicidal behavior in family members and nonfamilial associates on the subsequent suicidal behavior of male and female respondents of different ages. Across all studies, we found that prior suicidal behaviors among respondents' social groups were more important predictors of suicidal behavior in the respondents themselves than previous research had indicated. Community-based suicide attempters in the WHO SUPRE-MISS had higher rates of exposure to prior suicide in nonfamilial associates than in family members. In an ...

International Nuclear Information System (INIS)

Radiation hardening in austenitic stainless steels is shown to modify deformation characteristics and correlate well with an increased susceptibility to intergranular stress corrosion cracking (IGSCC). Available data on neutron-irradiated materials have been analyzed and correlations developed between fluence, yield strength and cracking susceptibility in high-temperature water environments. Large heat-to-heat differences in the critical fluence (0.2 to 2.5 x10"2"1 n/cm"2) for IGSCC are documented. In many cases, this variability is consistent with yield strength differences among irradiated materials. IGSCC correlates better to yield strength than to fluence for most heats suggesting a possible role of radiation-induced hardening and microstructure on cracking. Microstructural evolution during proton and heavy-ion irradiation has been characterized in low-carbon 304SSs. Hardening results from a dispersion of dislocation loops in the matrix which increase in density and size with ...

Energy Technology Data Exchange (ETDEWEB)

The corrosion and passivation behaviour of bulk polycrystalline martensite Ni{sub 50}Mn{sub 30}Ga{sub 20} and austenite Ni{sub 48}Mn{sub 30}Ga{sub 22} alloys was compared in electrolytes with different pH values. Linear anodic and cyclic potentiodynamic polarisation methods and anodic current transient measurements have been conducted for the alloys and their constituents to analyze free corrosion, anodic dissolution and passive layer formation processes. Electrochemically treated alloy surfaces were characterized with scanning electron microscopy (SEM) and angle-resolved x-ray photoelectron spectroscopy (XPS). The electrochemical response of both alloys is in principal similar and is dominated by the Ni oxidation. In acidic solutions (pH 0.5 and 5) a slightly higher reactivity is detectable for the martensitic alloy which is mainly attributed to enhanced dissolution processes at the multiple twin boundaries. In weakly acidic to strongly alkaline solutions (pH ...

Energy Technology Data Exchange (ETDEWEB)

COGNIS TERRAMET{reg_sign} soil leaching and Bescorp soil washing systems have been successfully combined to remediate an ammunition test burn area at the Twin Cities Army Ammunition Plant (TCAAP), New Brighton, MN. This cleanup is the first in the country to combine these two technologies, and this approach offers a permanent remedial solution. In Fall 1993, 1,600 tons of soil were remediated with an additional 10,000+ tons treated in 1994. The cleaned soil remained on-site, and the heavy metal contaminants were removed, recovered, and recycled. Eight heavy metals were removed from the contaminated soil achieving the very stringent cleanup criteria of <175 ppm for residual lead and achieving background concentrations for seven other heavy metals (antimony, cadmium, chromium, copper, mercury, nickel, and silver). In addition, both live and spent ordnance had to be removed in the soil treatment plant to meet the cleanup criteria. No hazardous waste requiring ...

Energy Technology Data Exchange (ETDEWEB)

The kraft recovery boiler is of critical importance for the paper and pulp industry. From only energy point of view, kraft recovery boilers supply more than 50% of total thermal energy consumed in the paper and pulp industry. A kraft recovery boiler has two main functions: firstly to recover the inorganic cooking chemicals in the black liquor for reuse in the pulping process, and secondly to make use of the chemical energy in the organic portion of the black liquor to generate super-heated steam for the plant. The twin objectives of recovering chemicals and energy makes the recovery boiler design and operation more complex than virtually any other boiler application. Thus there is a demand for development of an analytical tool that can be used to predict the performance of a kraft recovery boiler. This paper presents the results achieved from a project jointly financed by Swedish National Energy Administration and the industry (Iggesund Paperboard). In this ...