WorldWideScience
1

Palladium-catalyzed carbonylative coupling of benzyl chlorides with terminal alkynes to give 1,4-diaryl-3-butyn-2-ones and related furanones.  

Science.gov (United States)

A general palladium-catalyzed carbonylative Sonogashira coupling of benzyl chlorides with terminal acetylenes has been established. Depending on the alkyne 1,4-diaryl-3-butyn-2-ones or substituted furanones are obtained in moderate to good yields. Best catalytic performance is achieved applying a mixed Pd(PPh(3))Cl(2)/P(OPh)(3) catalyst system. PMID:21968528

2011-10-01

2

Palladium-catalyzed Heck-type reaction of oxime ether bearing a pendant vinyl iodide moiety.  

Science.gov (United States)

A Pd(0)-catalyzed intramolecular Heck-type reaction of oxime ether has been developed, providing convenient access to heterocyclic oximes. PMID:21964259

2011-10-01

3

tiAtiA ,', - NASA Technical Report Server (NTRS)  

Science.gov (United States)

the nozzle ring, the collector cup, and the impeller fuel-distribution ... sity of the vaned collector cup and the fuel-transfer passages ..... closure ...

4

Efficient synthesis of unsymmetric diarylalkynes from decarboxylative coupling in a continuous flow reaction system  

British Library Electronic Table of Contents (United Kingdom)

Unsymmetric diaryl alkynes were synthesized from the palladium-catalyzed decarboxylative coupling of aryl halides and propiolic acid using a continuous flow reaction system. This flow chemistry system continuously gave the desired products in moderate to good yields, and produced less byproduct than was formed in the batch reaction.

2011-01-01

5

Laparoscopic Orchiectomy and Subsequent Internal Ring Closure for Extra-abdominal Testicular Nubbin in Children  

British Library Electronic Table of Contents (United Kingdom)

Objectives To present our preliminary experience with laparoscopic groin exploration and subsequent laparoscopic orchiectomy and internal ring closure for testicular nubbin in children and discuss the usefulness of our new treatment strategy. The advantages of laparoscopic orchiopexy for intra-abdominal testis are the ability to start treatment as soon as a diagnosis has been made and to permit minimally invasive surgery. These advantages can apply to laparoscopic orchiectomy for a testicular nubbin. Methods A total of 6 boys with a testicular nubbin (age range 14-76 months, mean age 27.3 months) underwent laparoscopic orchiectomy at our institution from June 2007 to June 2008. We opened the posterior parietal peritoneum by incising the peritoneum lateral to the spermatic vessel, distal to...

2009-01-01

6

Closure of Off-Site Telnet  

CERN Document Server

Closure of Off-Site Telnet

2002-01-01

7

Palladium-catalyzed combustion of methane: Simulated gas turbine combustion at atmospheric pressure  

Energy Technology Data Exchange (ETDEWEB)

Atmospheric pressure tests were performed in which a palladium catalyst ignites and stabilizes the homogeneous combustion of methane. Palladium exhibited a reversible deactivation at temperatures above 750 C, which acted to ``self-regulate`` its operating temperature. A properly treated palladium catalyst could be employed to preheat a methane/air mixture to temperatures required for ignition of gaseous combustion (ca. 800 C) without itself being exposed to the mixture adiabatic flame temperature. The operating temperature of the palladium was found to be relatively insensitive to the methane fuel concentration or catalyst inlet temperature over a wide range of conditions. Thus, palladium is well suited for application in the ignition and stabilization of methane combustion.

1995-04-01

8

FULL CLOSURE MOTOR FOR DRIVING VEHICLE  

J-STORE (Japan)

Full Text Available

2007-11-02

9

Echocardiographic assessment and percutaneous closure of multiple atrial septal defects  

UK PubMed Central (United Kingdom)

Atrial septal defect closure is now routinely performed using a percutaneous approach under echocardiographic guidance. Centrally located, secundum defects are ideal for device closure but there is...Full Text Available

10

The synthesis of 5-[1-"1"1C]ethyl barbiturates from labelled malonic esters  

International Nuclear Information System (INIS)

The synthesis of ["1"1C]phenobarbital, ["1"1C]pentobarbital and["1"1C]amobarbital labelled in the 5-[1-"1"1C]ethyl position is reported. The malonic esters R- CH(CO_2Et)_2 [R phenyl-, 1-methylbutyl-, and 3- methylbutyl- were alkylated with [1-"1"1C]ethyl iodide prepared from ["1"1C]carbon dioxide. Ring closure of the 2-[1-"1"1C]ethyl-labelled malonic esters with urea afforded 5-[1-"1"1C]ethyl-phenobarbital,-phenobarbital, -pentobarbital and -amobarbital synthesis times of 42-47 min, counted from ["1"1C] carbon dioxide. In typical syntheses starting with 3 GBq pentobarbitol and (81 mCi) ["1"1C]carbon dioxide, 150-215 MBq (4-6 mCi) were produced in 25-30% decay corrected -amobarbital radiochemical yields with radiochemical purities greater than 98%. (author).

11

Effect of Stress and Strain Path on Cavity Closure During Hot ...  

Science.gov (United States)

... CLOSURE DURING HOT WORKING OF AN ALPHA/BETA TITANIUM ALLOY (PREPRINT) ... HOT WORKING OF AN ALPHA/BETA TITANIUM ALLOY ...

2007-07-01

14

Newly developed control and stop valves  

International Nuclear Information System (INIS)

... bwr type reactors closures fluidic control devices operation performance pwr

18

Operating Characteristics of a Three-Piece-Inner-Ring Large-Bore ...  

Science.gov (United States)

roller bearing with a one-piece inner ring. The lubricant experimental data on high-speed roller .... roller bearing. The outer ring of the test bearing was ...

20

Saturn's Recycling Rings - Cassini Solstice Mission - NASA  

Science.gov (United States)

Dec 12, 2007 ... This is an artist concept of a close-up view of Saturn's ring particles.

21

Alternative Loop Rings  

CERN Document Server

For the past ten years, alternative loop rings have intrigued mathematicians from a wide cross-section of modern algebra. As a consequence, the theory of alternative loop rings has grown tremendously. One of the main developments is the complete characterization of loops which have an alternative but not associative, loop ring. Furthermore, there is a very close relationship between the algebraic structures of loop rings and of group rings over 2-groups. Another major topic of research is the study of the unit loop of the integral loop ring. Here the interaction between loop rings and group ri

1996-01-01

22

Conventional Linear versus Purse-string Skin Closure after Loop Ileostomy Reversal: Comparison of Wound Infection Rates and Operative Outcomes  

UK PubMed Central (United Kingdom)

PurposeWound infection after an ileostomy reversal is a common problem. To reduce wound-related complications, purse-string skin closure was introduced as an alternative to conventional...Full Text Available

2011-04-01

23

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

24

The closure operator in a multivalued logic based on functional equations  

British Library Electronic Table of Contents (United Kingdom)

An operator of FE-closure is introduced on the set of functions of a multivalued logic based on the systems of functional equations. It is proved that, for every k ? 2, the FE-closure operator generates a finite classification on the set P k of functions of k-valued logic. The least class in this classification is shown to be the class H k of all homogeneous functions. Also a series of corollaries are obtained concerning the finite FE-generating sets in the FE-closed classes.

2011-01-01

25

Amchitka Mud Pit Sites 2006 Post-Closure Monitoring and Inspection Report, Amchitka Island, Alaska, Rev. No.: 0  

Energy Technology Data Exchange (ETDEWEB)

In 2001, the U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA/NSO) remediated six areas associated with Amchitka mud pit release sites located on Amchitka Island, Alaska. This included the construction of seven closure caps. To ensure the integrity and effectiveness of remedial action, the mud pit sites are to be inspected every five years as part of DOE's long-term monitoring and surveillance program. In August of 2006, the closure caps were inspected in accordance with the ''Post-Closure Monitoring and Inspection Plan for Amchitka Island Mud Pit Release Sites'' (Rev. 0, November 2005). This post-closure monitoring report provides the 2006 cap inspection results.

2006-09-01

26

JHK and 3.3um PAH Imaging of the Starburst Ring in the Type I Seyfert Galaxy NGC 7469  

Science.gov (United States)

Imaging of NGC 7469 in the J, H, & K bands shows that the starburst 'ring' is a tight inner

1993-01-01

27

Military Base Closures and Affected Defense Department Civil ...  

Science.gov (United States)

... System (CSRS) and the Federal Employees Retirement System (FERS). ... retirement, thrift savings plan, annual and sick leave, severance pay and ...

2006-03-07

28

Laser Surface Mapping of the Failed FB-Line Bagless Canister Closure Weld  

Energy Technology Data Exchange (ETDEWEB)

This report details the laser surface mapping activity as described in technical tasks and QA plan 22751-TTQAP-LM.

2000-06-27

29

EUROPEAN SPACE AGENCY Extension of the SOHO Mission  

Science.gov (United States)

closure of the BISON network, GOLF and VIRGO will remain the only instruments ...... Faraday Cup solar wind instrument as described in Ipavich et al (1998). ...

33

Transesophageal echo to help percutaneous closure of ventricular septal defect post acute myocardial infarction  

British Library Electronic Table of Contents (United Kingdom)

Ventricular septal defect after acute myocardial infarction (AMI) is a complication associated with poor outcome in the absence of intervention. We report a case of successful TEE guided transcatheter closure of a post myocardial infarction (MI) ventricular septal defect (VSD) with an Amplatzer occluder in a 79 years old male with cardiogenic shock.

2011-01-01

34

The Risk of Paradoxical Embolism (RoPE) Study: Developing risk models for application to ongoing randomized trials of percutaneous patent foramen ovale closure for cryptogenic stroke  

UK PubMed Central (United Kingdom)

BackgroundDespite the diffusion into practice of percutaneous closure of a patent foramen ovale (PFO) in patients with cryptogenic stroke (CS), the benefits have not been demonstrated,...Full Text Available

35

Interim safety basis for fuel supply shutdown facility  

Energy Technology Data Exchange (ETDEWEB)

This ISB in conjunction with the new TSRs, will provide the required basis for interim operation or restrictions on interim operations and administrative controls for the Facility until a SAR is prepared in accordance with the new requirements. It is concluded that the risk associated with the current operational mode of the Facility, uranium closure, clean up, and transition activities required for permanent closure, are within Risk Acceptance Guidelines. The Facility is classified as a Moderate Hazard Facility because of the potential for an unmitigated fire associated with the uranium storage buildings.

1995-05-23

36

Effects of Temperature on H+ Secretion and Uptake by Excised Flexor Cells during Dark-Induced Closure of Samanea Leaflets 1  

UK PubMed Central (United Kingdom)

Previous studies reveal that dark-induced closure of Samanea leaflets is accompanied by H+ secretion from flexor motor cells. We now report that flexor tissue excised in...Full Text Available

1987-11-01

37

Inner ring structures in galaxies as distance indicators. I. Dimensionless systematics of inner rings  

International Nuclear Information System (INIS)

Inner ring structures are observed in about one quarter of all lenticular or spiral galaxies. Statistics of the relative frequencies of the pure ring (r) and broken ring (rs) varieties in the Second Reference Catalogue (RC2) among the different families (A, AB, B) of lenticular (L) and spiral (S) galaxies at different stages (T) along the revised Hubble sequence are presented; selection effects dependent on classification weight, apparent diameter and axis ratio are discussed. Comparisons of ring diameters D/sub r/ listed in the (First) Reference Catalogue (RC1) with independent measurements of 43 barred systems by Kormendy show good systematic agreement with a standard deviation sigma_1_2(D/sub r/) = 0'.10 and individual relative mean errors sigma(D/sub r/)/ < D/sub r/ > approx. = 5%. Axis ratios are also in good agreement with sigma_1_2(b/a) = 0.06. Comparisons of axis ratios of ...

38

Streamlined Approach for Environmental Restoration (SAFER) Plan for Corrective Action Unit 118: Area 27 Super Kukla Facility, Nevada Test Site, Nevada, Rev. No.: 1  

Energy Technology Data Exchange (ETDEWEB)

This Streamlined Approach for Environmental Restoration (SAFER) plan addresses closure for Corrective Action Unit (CAU) 118, Area 27 Super Kukla Facility, identified in the ''Federal Facility Agreement and Consent Order''. Corrective Action Unit 118 consists of one Corrective Action Site (CAS), 27-41-01, located in Area 27 of the Nevada Test Site. Corrective Action Site 27-41-01 consists of the following four structures: (1) Building 5400A, Reactor High Bay; (2) Building 5400, Reactor Building and access tunnel; (3) Building 5410, Mechanical Building; and (4) Wooden Shed, a.k.a. ''Brock House''. This plan provides the methodology for field activities needed to gather the necessary information for closing the CAS. There is sufficient information and process knowledge from historical documentation and site confirmation data collected in 2005 and 2006 to recommend closure of ...

2006-09-01

39

Studies of accelerated compact toruses  

Energy Technology Data Exchange (ETDEWEB)

In an earlier publication we considered acceleration of plasma rings (Compact Torus). Several possible accelerator configurations were suggested and the possibility of focusing the accelerated rings was discussed. In this paper we consider one scheme, acceleration of a ring between coaxial electrodes by a B/sub theta/ field as in a coaxial rail-gun. If the electrodes are conical, a ring accelerated towards the apex of the cone undergoes self-similar compression (focusing) during acceleration. Because the allowable acceleration force, F/sub a/ = kappaU/sub m//R where (kappa < 1), increases as R/sup -2/, the accelerating distance for conical electrodes is considerably shortened over that required for coaxial electrodes. In either case, however, since the accelerating flux can expand as the ring moves, most of the accelerating field energy can be converted into kinetic energy of the ...

1983-01-04

40

Stability of the viscously spreading ring  

CERN Document Server

We study analytically and numerically the stability of the pressure-less, viscously spreading accretion ring. We show that the ring is unstable to small non-axisymmetric perturbations. To perform the perturbation analysis of the ring we use a stretching transformation of the time coordinate. We find that to 1st order, one-armed spiral structures, and to 2nd order additionally two-armed spiral features may appear. Furthermore, we identify a dispersion relation determining the instability of the ring. The theoretical results are confirmed in several simulations, using two different numerical methods. These computations prove independently the existence of a secular spiral instability driven by viscosity, which evolves into persisting leading and trailing spiral waves. Our results settle the question whether the spiral structures found in earlier simulations of the spreading ring are ...

2003-01-01

41

COSY synchrotron and storage ring for medium energy physics  

Energy Technology Data Exchange (ETDEWEB)

At present the cooler synchrotron COSY a synchrotron and storage ring for medium energy physics is being commissioned at Juelich. The construction of the ring was finished during September 1992. The cooler ring will deliver protons in the momentum range from 270 to 3300 MeV/c. The phase density of the circulating protons will be increased with electron cooling at injection and with stochastic cooling at momenta between 1500 and 3300 MeV/c. High luminosity internal experiments as well as high resolution external experiments will be possible. Details of the lattice, to match the different ion optical requirements for cooling, acceleration, internal experiments and ultra-slow extraction will be discussed. An overview of the performance of the ion sources, the injector cyclotron, the ring, the injection beamline are given. The realization status of the extraction beamlines to the external experimental area ...

1993-01-01

42

Combined bony closure of oroantral fistula and sinus lift with mandibular bone grafts for subsequent dental implant placement  

British Library Electronic Table of Contents (United Kingdom)

Sinus lifting and reconstruction of localized alveolar defects are often required after closure of a large oroantral fistula (OAF) to allow for subsequent implant installation. This study describes a combined surgical technique that involves sinus lifting, bony closure, and reconstruction of the alveolar defect at the site of an OAF. The sinus membrane was reconstructed as a continuous layer by combining the residual sinus membrane with a rotated part of oral mucosa around the OAF. Autogenous bone from the chin and/or ramus was grafted into the prepared sinus space and alveolar defect, and the graft was covered by a buccal advancement flap. This technique was used to treat 8 patients who had large OAFs in the posterior maxillary region. The treatment was successful in all cases, and the te...

2011-01-01

43

Xylem Embolism in Response to Freeze-Thaw Cycles and Water Stress in Ring-Porous, Diffuse-Porous, and Conifer Species 1  

UK PubMed Central (United Kingdom)

Vulnerability to xylem embolism by freeze-thaw cycles and water stress was quantified in ring-porous (Quercus gambelii Nutt.), diffuse-porous (Populus tremuloides Michx.,...Full Text Available

1992-10-01

44

Ring opening reaction dynamics of a photochromic diarylethene derivative dye  

International Nuclear Information System (INIS)

Ring opening dynamics of diarylethene derivative (BTF6) in n-hexane are studied by femtosecond transient absorption and time resolved spontaneous fluorescence techniques. Cyclo-reversion time constant is obtained.

2001-11-01

45

Resonance Raman enhancement of phenyl ring vibrational modes in phenyl iron complex of myoglobin.  

UK PubMed Central (United Kingdom)

Resonance Raman spectra are reported for the organometallic phenyl-FeIII complexes of horse heart myoglobin. We observed the resonance enhancement of the ring vibrational modes of the bound phenyl group....Full Text Available

1990-04-01

46

Proton storage ring (PSR) diagnostics and control system  

Energy Technology Data Exchange (ETDEWEB)

When any new accelerator or storage ring is built that advances the state of the art, the diagnostic system becomes extremely important in tuning the facility to full specification. This paper will discuss the various diagnostic devices planned or under construction for the PSR and their connection into the control system.

1983-01-01

47

Electron Flux - 8.0 keV - ISWA wiki - ISWA - NASA  

Science.gov (United States)

Nov 14, 2009 ... Ring Current electrons from the Fok Ring Current Model are computed using plasma and magnetic field values from the SWMF magnetosphere ...

48

Electron Flux - 4.7 keV - ISWA wiki - NASA  

Science.gov (United States)

Nov 14, 2009 ... Ring Current electrons from the Fok Ring Current Model are computed using plasma and magnetic field values from the SWMF magnetosphere ...

49

Electron Flux - 179 keV - ISWA wiki - ISWA - NASA  

Science.gov (United States)

Nov 14, 2009 ... Ring Current electrons from the Fok Ring Current Model are computed using plasma and magnetic field values from the SWMF magnetosphere ...

50

Algebraic Structure of Linear Dynamical Systems. III. Realization Theory Over a Commutative Ring  

UK PubMed Central (United Kingdom)

The realization theory linear dynamical systems, previously developed over a field, are extended to a large class of commutative rings. The principal result is that the existence criterion for a finite...Full Text Available

1972-11-01

51

Gunsof - NASA  

Science.gov (United States)

end of the barrel. The petal valve and ring seal are inserted behind it, and the gun barrel assembly and HP section are clamped together with hydraulic collars. ...

52

FINITE ELEMENT OPTIMIZATION OF FIELD ...  

Science.gov (United States)

... Title : FINITE ELEMENT OPTIMIZATION OF FIELD CONFIGURATION FOR THE EDDY CURRENT TESTING OF ROLLER BEARING RIB RINGS. ...

1988-04-01

53

Developing methods for testing and monitoring packing, detachable connections used in well geophysical apparatus. O razrabotke metodov ispytaniy i kontrolya uplotnitel'nykh raz''yemnykh soyedineniy, primenyayemykh v skvazhinnoy geofizicheskoy apparature  

Energy Technology Data Exchange (ETDEWEB)

Development of surface monitoring of the quality of round rubber packing rings for well instruments is discussed. A method is shown for testing the rings under conditions which simulate the operating conditions. A method is proposed for rapid monitoring of the conditions for vulcanization of the rings by the method of determining the ''ring modulus.''

1983-01-01

54

Successful Treatment of Anterior Tracheal Necrosis after Total Thyroidectomy Using Vacuum-Assisted Closure Therapy  

UK PubMed Central (United Kingdom)

Total thyroidectomy involving the adjacent structures of the trachea can cause tracheal damage such as early tracheal necrosis. The authors describe the first case of anterior tracheal necrosis following...Full Text Available

2012-01-01

55

Relationship of Xylem Embolism to Xylem Pressure Potential, Stomatal Closure, and Shoot Morphology in the Palm Rhapis excelsa1  

UK PubMed Central (United Kingdom)

Xylem failure via gas embolism (cavitation) induced by water stress was investigated in the palm Rhapis excelsa (Thumb.) Henry. Xylem embolism in excised stems and petioles was detected...Full Text Available

1986-01-01

56

Prostaglandin-mediated closure of paracellular pathway and not restitution is the primary determinant of barrier recovery in acutely injured porcine ileum  

UK PubMed Central (United Kingdom)

SUMMARYSmall bowel epithelium is at the frontline of intestinal barrier function. Restitution is considered to be the major determinant of epithelial repair as function recovers...Full Text Available

2003-11-01

57

Over-the-scope clip closure of two chronic fistulas after gastric band penetration  

UK PubMed Central (United Kingdom)

Gastrointestinal perforations are conservatively managed at endoscopy by through-the-scope endoclips and covered self expandable stents, according to the size and tissue features of the perforation....Full Text Available

2010-04-07

58

On the internal perceptual structure of distinctive features: The [voice] contrast  

UK PubMed Central (United Kingdom)

Several fixed classification experiments test the hypothesis that F1, f0, and closure voicing covary between intervocalic stops contrasting...Full Text Available

2008-01-01

59

Hanford facility dangerous waste permit application, general information portion  

Energy Technology Data Exchange (ETDEWEB)

The `Hanford Facility Dangerous Waste Permit Application` is considered to be a single application organized into a General Information Portion (this document, DOE/RL-91-28) and a Unit- Specific Portion. The scope of the General Information Portion includes information that could be used to discuss operating units, units undergoing closure, or units being dispositioned through other options. Documentation included in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units. A checklist indicating where information is contained in the General Information Portion, in relation to the Washington State Department of Ecology guidance documentation, is located in the Contents Section. The intent of the General Information Portion is: (1) to provide an overview of the Hanford Facility; and (2) to assist in streamlining efforts associated with treatment, storage, and/or disposal unit-specific Part B permit ...

1996-07-29

60

FFTF reactor assembly system technology  

Science.gov (United States)

An overview is presented of the FFTF reactor and plant together with descriptions of core components, core internals, core system, primary and secondary control rod system, reactor instrumentation, reactor vessel and closure head, and supporting test programs. (DG)

1975-11-13

61

FFTF reactor assembly system technology  

International Nuclear Information System (INIS)

An overview is presented of the FFTF reactor and plant together with descriptions of core components, core internals, core system, primary and secondary control rod system, reactor instrumentation, reactor vessel and closure head, and supporting test programs.

1976-03-13

62

Effect of the ASARCO smelter shutdown on the acidity of rainfall in the Puget sound area  

Science.gov (United States)

The influence of the sulfur dioxide emissions from a large copper smelter in Tacoma, Washington, USA, was studied by measuring the chemical composition of rainwater collected upwind and downwind of the source, before and after permanent closure of the smelter in 1985. Data analysis was based on a statistical model that accounted for variability associated with location of 25 sampling sites within three geographic regions, smelter operation, ten individual rain events observed over 2 years, and measurement uncertainty. After smelter closure, the upwind-downwind differences in mean hydrogen ion and excess sulfate ion concentrations within a 600 km/sup 2/ region extending to 25 km downwind of the source had decreased significantly compared to the pre-closure value. No significant decreases in mean ion concentrations were observed farther downwind in the Seattle, urban area. During five events sampled prior to smelter ...

1988-04-01

63

A late presenting congenital diaphragmatic hernia misdiagnosed as spontaneous pneumothorax  

UK PubMed Central (United Kingdom)

Congenital diaphragmatic hernia (CDH) is described as (1) failure of diaphragmatic closure at development, (2) presence of herniated abdominal contents into chest and (3) pulmonary hypoplasia. Usually,...Full Text Available

2010-09-01

64

{Beta} decay and isomeric properties of neutron-rich Ca and Sc isotopes.  

Energy Technology Data Exchange (ETDEWEB)

The isomeric and {beta}-decay properties of neutron-rich {sup 53-57}Sc and {sup 53,54}Ca nuclei near neutron number N = 32 are reported, and the low-energy level schemes of {sup 53,54,56}Sc and {sup 53-57}Ti are presented. The low-energy level structures of the {sub 21}Sc isotopes are discussed in terms of the coupling of the valence 1f{sub 7/2} proton to states in the corresponding {sub 20}Ca cores. Implications with respect to the robustness of the N = 32 subshell closure are discussed, as well as the repercussions for a possible N = 34 subshell closure.

2010-07-21

65

Two-proton excitations at the Z=38 and Z=40 sub-shell closures  

International Nuclear Information System (INIS)

The "8"6Kr("3He,n)"8"8Sr and "8"8Sr("3He,n)"9"0Zr reactions were studied to determine whether significant excited 0"+ strength was observed or whether these nuclei exhibited absence of excited state strength generally seen away from shell closures. Various properties of the levels are considered including angular distributions, spins, parities, interference, and enhancement. It is concluded that neither "8"8Sr nor "9"0Zr exhibit the strong proton pairing vibration expected for a closed proton shell nucleus.

1977-11-01

66

Persistence of the N=28 shell closure far from stability  

Science.gov (United States)

The masses of 16 neutron-rich nuclei in the mass range from 35 to 45 have been measured using a direct time of flight technique following the fragmentation of a {sup 48}Ca beam at 60 MeV/nucleon. The masses of {sup 35,36}Mg, {sup 38}Al, {sup 39,40}Si, {sup 42,43}P and {sup 43,44}S are reported for the first time. Preliminary analysis shows that the N=28 shell closure persists, even if weakened by the large neutron excess.

1998-12-21

67

Persistence of the N=28 shell closure far from stability  

International Nuclear Information System (INIS)

The masses of 16 neutron-rich nuclei in the mass range from 35 to 45 have been measured using a direct time of flight technique following the fragmentation of a "4"8Ca beam at 60 MeV/nucleon. The masses of "3"5","3"6Mg, "3"8Al, "3"9","4"0Si, "4"2","4"3P and "4"3","4"4S are reported for the first time. Preliminary analysis shows that the N=28 shell closure persists, even if weakened by the large neutron excess.

1998-12-21

68

? decay and isomeric properties of neutron-rich Ca and Sc isotopes  

International Nuclear Information System (INIS)

The isomeric and ?-decay properties of neutron-rich 53-57Sc and 53,54Ca nuclei near neutron number N=32 are reported, and the low-energy level schemes of 53,54,56Sc and 53-57Ti are presented. The low-energy level structures of the 21Sc isotopes are discussed in terms of the coupling of the valence 1f7/2 proton to states in the corresponding 20Ca cores. Implications with respect to the robustness of the N=32 subshell closure are discussed, as well as the repercussions for a possible N=34 subshell closure.

2010-07-01

69

Closure Report for Corrective Action Unit 543: Liquid Disposal Units, Nevada Test Site, Nevada  

Energy Technology Data Exchange (ETDEWEB)

This Closure Report (CR) documents closure activities for Corrective Action Unit (CAU) 543, Liquid Disposal Units, according to the Federal Facility Agreement and Consent Order (FFACO, 1996) and the Corrective Action Plan (CAP) for CAU 543 (U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office [NNSA/NSO], 2007). CAU 543 is located at the Nevada Test Site (NTS), Nevada (Figure 1), and consists of the following seven Corrective Action Sites (CASs): CAS 06-07-01, Decon Pad; CAS 15-01-03, Aboveground Storage Tank; CAS 15-04-01, Septic Tank; CAS 15-05-01, Leachfield; CAS 15-08-01, Liquid Manure Tank; CAS 15-23-01, Underground Radioactive Material Area; CAS 15-23-03, Contaminated Sump, Piping; and CAS 06-07-01 is located at the Decontamination Facility in Area 6, adjacent to Yucca Lake. The remaining CASs are located at the former U.S. Environmental Protection Agency (EPA) Farm in Area 15. The purpose of this CR is to ...

2008-01-01

70

Tunable erbium-doped fiber ring laser for applications of infrared absorption spectroscopy  

British Library Electronic Table of Contents (United Kingdom)

We fabricate a low noise erbium-doped fiber ring laser that can be continuously tuned over 102nm by insertion of the fiber Fabry-Perot tunable filter (FFP-TF) in the ring cavity with a novel cavity structure and the optimal gain medium length. As an application of this fiber ring laser, we performed the absorption spectroscopy of acetylene (13C2H2) and hydrogen cyanide (H13C14N) and measure the absorption spectra of more than 50 transition lines of these gases with an excellent signal to noise ratio (SNR). The pressure broadening coefficients of four acetylene transition lines are obtained using this fiber ring laser and an external cavity laser diode.

2007-01-01

71

Syzygy Theorems via comparison of order ideals on a hypersurface  

British Library Electronic Table of Contents (United Kingdom)

We introduce a weak order ideal property that suffices for establishing the Evans-Griffith Syzygy Theorem. We study this weak order ideal property in settings that allow for comparison between homological algebra over a local ring R versus a hypersurface ring R =R/(x^n). Consequently we solve some relevant cases of the Evans-Griffith syzygy conjecture over local rings of unramified mixed characteristic p, with the case of syzygies of prime ideals of Cohen-Macaulay local rings of unramified mixed characteristic being noted. We reduce the remaining considerations to modules annihilated by p^s, s>0, that have finite projective dimension over a hypersurface ring.

2012-01-01

72

Effect of the repulsive core on the exciton spectrum in a quantum ring  

Energy Technology Data Exchange (ETDEWEB)

A theoretical study of an exciton confined in a quantum ring is presented. The quantum ring is described as a two-dimensional circular quantum dot with a repulsive core, which is modelled with the help of two Gaussian functions. We have applied the variational method and investigated the evolution of the low-energy exciton spectrum with the change of the confinement potential. The calculations have been performed for the recently produced self-assembled ring-shaped InGaAs quantum dots. We have shown that the repulsive core strongly increases the radiative transition probability from the exciton ground state at the expense of the decreasing probability of the transitions from the excited states. This effect results from the orthogonality properties of the exciton wavefunctions, which are specific to the quantum-ring confinement potential. We have studied the characteristic features of the exciton ...

2002-01-14

73

Are the delay images necessary to evaIuate the liver metastatic lesions on mangafodipir trisodium enhanced liver MRI?: comparison with hepatocellular carcinomas  

Energy Technology Data Exchange (ETDEWEB)

To assess whether ring enhancements of liver metastases on Mn-DPDP enhanced, early MR images were well visualized on delayed images, as compared with those of hepatocellular carcinomas (HCC), and to investigate the detection accuracy and conspicuity of each tumor. Twenty patients with liver metastases and 15 with HCC were studied by Mn-DPDP enhanced, T1-weighted MR images. Peripheral ring enhancement and conspicuity were investigated. Differences in detection accuracy and frequency of ring enhancement in liver metastases and HCC were assessed. In liver metastases (n= 69), 44 cases (63.8%) without ring enhancement and 25 (36.2%) with were noted on early images. Sixteen cases (23.2%) without ring enhancement, 38 (55.1%) with ring enhancement similar to the early images, and 15 (21.7%) with prominent ring enhancement were noted on delayed ...

2004-09-01

74

A multi-wavelength scattered light analysis of the dust grain population in the GG Tau circumbinary ring  

Energy Technology Data Exchange (ETDEWEB)

We present the first 3.8 {micro}m image of the dusty ring surrounding the young binary system GG Tau, obtained with the W. M. Keck II 10m telescope's adaptive optics system. THis is the longest wavelength at which the ring has been detected in scattered light so far, allowing a multi-wavelength analysis of the scattering proiperties of the dust grains present in this protoplanetary disk in combination with previous, shorter wavelengths, HST images. We find that the scattering phase function of the dust grains in the disk is only weakly dependent on the wavelength. This is inconsistent with dust models inferred from observations of the interstellar medium or dense molecular clouds. In particular, the strongly forward-throwing scattering phase function observed at 3.8 {micro}m implies a significant increase in the population of large ({approx}> 1 {micro}m) grains, which provides direct evidence for grain growth in the ...

2004-02-04

75

Interactions of Jet Fuels with Nitrile O-Rings: Petroleum-Derived versus Synthetic Fuels  

Energy Technology Data Exchange (ETDEWEB)

A transition from petroleum~derived jet fuels to blends with Fischer-Tropsch (F~T) fuels, and ultimately fully synthetic hydro-isomerized F-T fuels has raised concern about the fate of plasticizers in nitrile-butadiene rubber a-rings that are contacted by the fuels as this transition occurs. The partitioning of plasticizers and fuel molecules between nitrile a-rings and petroleum-derived, synthetic, and additized-synthetic jet fuels has been measured. Thermal desorption of o-rings soaked in the various jet fuels followed by gas chromatographic analysis with a mass spectrometric detector showed many of the plasticizer and stabilizer compounds were removed from the o-rings regardless of the contact fuel. Fuel molecules were observed to migrate into the o-rings for the petroleum-derived fuel as did both the fuel and additive for a synthetic F-T jet fuel additized with benzyl alcohol, ...

2009-01-01

76

IN VACUUM UNDULATOR TASK FORCE REPORT  

Energy Technology Data Exchange (ETDEWEB)

The Green-Chasman lattice, which is the basis for both NSLS storage rings, was conceived with insertion devices in mind. Long, field-free straight sections were provided in the design. The electron optics were chosen so that these sections had zero dispersion and the effects of new magnetic structures placed in these regions would have minimal effect on the emittance of the electron beam. This design concept has been followed by all high-brightness rings which were built subsequent to the NSLS. The X-Ray Ring straight sections also have a very small vertical {beta} function, in addition to the zero dispersion. This was done to optimize the brightness of wiggler sources. There is a further benefit however. The {beta} function determines the beam size and divergence at a particular point in the storage ring lattice. The size is proportional to {radical}{beta} and the divergence is proportional to ...

1998-06-01

77

Unitizations of double-ring structure and Erbium-doped waveguide amplifier for stable and tunable fiber laser  

British Library Electronic Table of Contents (United Kingdom)

We propose and demonstrate experimentally a singlelongitudinal-mode (SLM) fiber double-ring laser using an Erbium-doped waveguide amplifier (EDWA), polarization controller (PC), and a fiber Fabry-Perot tunable filter (FFP-TF) into the ring cavity. In addition, the output power, side-mode suppression ratio (SMSR), and the stabilities of power and wavelength of the laser also are investigated. (Copyright 2007 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA)

2007-01-01

78

Thermal-hydraulics performance optimization of Candu fuel using Assert subchannel code  

Energy Technology Data Exchange (ETDEWEB)

An optimization of fuel bundle geometry using the subchannel code ASSERT is performed in support of Candu fuel design to enhance the thermohydraulics performance. The new bundle design is based on a reference CANFLEX bundle with changes to the centre and inner-ring element diameters and pitch-circle diameters (PCDs) of various element rings. Different methods of varying the PCDs for reaching the optimized geometry are considered in an attempt to minimize the optimization effort. The optimized geometry in the present analysis is the one that maximizes the dryout power and that has simultaneous CHF (critical heat flux) initiation involving more than one subchannel rings. (authors)

2007-07-01

79

REQUIREMENTS AND GUIDELINES FOR NSLS EXPERIMENTAL BEAM LINE VACUUM SYSTEMS-REVISION B.  

Energy Technology Data Exchange (ETDEWEB)

Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas after a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic ...

1999-05-01

80

Entangled quantum currents in distant mesoscopic Josephson junctions  

Energy Technology Data Exchange (ETDEWEB)

Two mesoscopic SQUID rings which are far from each other are considered. A source of two-mode nonclassical microwaves irradiates the two rings with correlated photons. The Josephson currents are in this case quantum mechanical operators, and their expectation values with respect to the density matrix of the microwaves yield the experimentally observed currents. Classically correlated (separable) and quantum mechanically correlated (entangled) microwaves are considered, and their effect on the Josephson currents is quantified. Results for two different examples that involve microwaves in number states and coherent states are derived. It is shown that the quantum statistics of the tunnelling electron pairs through the Josephson junctions in the two rings are correlated.

2004-12-22

81

Effect of mean stress (stress ratio) and aging on fatigue-crack growth in a metastable beta titanium alloy, Ti-10V-2Fe-3Al  

International Nuclear Information System (INIS)

The effect of mean stress, or the stress ratio (R), on the fatigue-crack growth (FCG) behavior of #alpha#-aged and #omega#-aged microstructures of the beta titanium alloy Ti-10V-2Fe-3Al was investigated. While the mean stress had a negligible effect on the FCG behavior of the #alpha#-aged microstructure, a strong effect was observed in the #omega#-aged microstructure. In particular, the values of the threshold stress-intensity range (#DELTA#K_t_h) exhibited a strong dependence on R in the #omega#-aged microstructure, while this dependence was weak in the #alpha#-aged microstructure. These effects seem to arise primarily from fracture-surface roughness-induced crack closure. The crack closure levels for the #alpha#-aged microstructure were found to be very low compared to those for the #omega#-aged microstructure. Transmission electron microscopy and scanning electron microscopy studies of microstructures and fracture surfaces were performed to ...

2000-03-01

83

Study of free electron laser (FEL) using the electron storage ring 'NIJI-IV'  

International Nuclear Information System (INIS)

We have constructed a racetrack-type compact electron storage ring 'NIJI-IV' for UV FEL. The ring has a hexagonal configuration with two 7.25 m-long straight sections, though its circumference is 29.6 m. A 6.3 m optical klystron (OK) for high FEL gain was installed in one of the long straight sections. The experimental setup for FEL lasing was started at the end of April 1992. The setup on the ring with the OK and the cavity mirror alignment have been completed. The FEL lasings using the NIJI-IV were accomplished at 595-589 nm on August 18, 1992 and at 488 nm on September 18, 1992. The final development target is stable FEL lasing in the UV range. (author).

84

NASA - Act of Creation  

Science.gov (United States)

Act of Creation. 01.08.07. Act of Creation. Prometheus dips into the inner F ring at its farthest point from Saturn in its orbit, creating a dark gore and a ...

85

Helium/solid powder O-ring leakage correlation experiments using a radiotracer  

Energy Technology Data Exchange (ETDEWEB)

UO/sub 2/ definitely leaked past the O-ring in three of the tests confirming the major results of the previous work. Continuous leakage at these levels may require additional precautions under present regulatory policies. The mechanism and the time and particle size dependence for the leakage are not known, but there is some indication leakage is more likely at low temperatures. It is possible leakage is due to movement of the O-ring during temperature or pressure cycling at the beginning or end of a test. The radiotracer method involves less labor and is much less susceptible to contamination than the previous method. Future work will investigate leakage past lubricated O-rings and time dependence of leakage. 1 reference, 1 table.

1984-01-01

86

Extending the service life and power of a gas laser with a coaxial continuous cathode  

Energy Technology Data Exchange (ETDEWEB)

A continuous gas laser may be operated reliably with an increased pressure level and current level without significant cathode sputtering. This increases the service life and the specific power of the laser. The design eliminates the formation of arcs in operational conditions, which also has a positive influence on laser operation. The proposed laser is used successfully in modern interferometry, in geodesy and in materials analysis. The laser design is characterized by the presence of separation rings inside the coaxial cathode. The separation rings are fastened to the anode. The anode is a perforated tube that is connected to two final protective rings. Electrodes from the housing pass through the final rings. In order to increase laser power, two or more lasers of such design are used and are positioned on the same axis in a single housing.

1983-12-31

87

ENGIN\\EE=RING  

Science.gov (United States)

Graphitized thermal carbon black has also been reported by Kalaschinikova et al. (11) to have excellent adsorption properties for CI-C6 alkanes, ...

88

Development of a 2-Aza-Cope-[3+2] Dipolar Cycloaddition Strategy for the Synthesis of Quaternary Proline Scaffolds  

UK PubMed Central (United Kingdom)

A one-pot multicomponent procedure for the synthesis of highly functionalized pyrrolidine rings through a domino...Full Text Available

2010-09-03

89

Conceptual Design of a Support Structure and an Assemble of Detectors Inside a Large Solenoid  

CERN Document Server

In this note we describe a support structure which will hold detector systems (ITS, TPC, TOF) inside the large solenoid. An overall view of ALICE detector is shown on Fig.1. The support structure consists of 2 rings which fixed to an iron yoke and spokes which connect TPC and TOF to these rings. The ITS is connected by spokes to TPC end caps. Between coils there are 7cm spacings which will allow to fix rings to the yoke this support structure will allow to assemble ITS, TPC and TOF together (Fig.2) somewhere on the surface and then transport to the pit and install in the magnet. Two rings (1) are connected with four bars (2). On the bottom bars there are rolls (3) which will allow smoothly insert detectors into the magnet. Spokes (4) are uniformly distributed.

1993-01-01

90

Shipping container response to three severe railway accident scenarios  

Energy Technology Data Exchange (ETDEWEB)

The probability of damage and the potential resulting hazards are analyzed for a representative rail shipping container for three severe rail accident scenarios. The scenarios are: (1) the rupture of closure bolts and resulting opening of closure lid due to a severe impact, (2) the puncture of container by an impacting rail-car coupler, and (3) the yielding of container due to side impact on a rigid uneven surface. The analysis results indicate that scenario 2 is a physically unreasonable event while the probabilities of a significant loss of containment in scenarios 1 and 3 are extremely small. Before assessing the potential risk for the last two scenarios, the uncertainties in predicting complex phenomena for rare, high- consequence hazards needs to be addressed using a rigorous methodology.

1998-04-01

91

Goal-based waste management strategy to reduce persistence of contaminants in leachate at municipal solid waste landfills  

British Library Electronic Table of Contents (United Kingdom)

The required minimum 30-year post-closure care period for municipal solid waste (MSW) landfills can be shortened by reducing or eliminating of MSW components with long-terms effect in gas and leachate. The objectives of this study were to evaluate the relative persistence of landfill gas, leachate quantity, and selected leachate parameters using post-closure monitoring data from a case study landfill in south Florida. The relative persistence of selected decomposition byproducts in leachate were evaluated by both zero order and first order models based on monitoring data from the case study landfill. The analyses show that although gas and leachate production rates diminish very quickly, some contaminants remain in leachate as the decomposition process continues at a slower rate. For the c...

2011-01-01

92

Forward on the N=Z line with GASP  

Energy Technology Data Exchange (ETDEWEB)

The experimental study of the proton-rich nuclei close to the N=Z line is a constant challenge for nuclear spectroscopy, mainly due to the difficulty to produce them with the currently available beam/target combinations. Significant advances on this direction were obtained from experiments performed with the GASP array during the last two years: the yrast line of {sup 84}Mo was extended up to 10{sup +}, {sup 88}Ru observed for the first time, and the N=Z+1 line was mapped from {sup 81}Zr to {sup 95}Ag. These new results allow us to have a more complete image of the transition from the well-deformed shell closure at N,Z=40 to the spherical-shell closure at N,Z=50, and highlights some particular effects that can be observed only in the vicinity of the N=Z line. (orig.)

2004-04-01

93

Forward on the N=Z line with GASP  

International Nuclear Information System (INIS)

The experimental study of the proton-rich nuclei close to the N=Z line is a constant challenge for nuclear spectroscopy, mainly due to the difficulty to produce them with the currently available beam/target combinations. Significant advances on this direction were obtained from experiments performed with the GASP array during the last two years: the yrast line of "8"4Mo was extended up to 10"+, "8"8Ru observed for the first time, and the N=Z+1 line was mapped from "8"1Zr to "9"5Ag. These new results allow us to have a more complete image of the transition from the well-deformed shell closure at N,Z=40 to the spherical-shell closure at N,Z=50, and highlights some particular effects that can be observed only in the vicinity of the N=Z line. (orig.)

2004-04-01

94

Environmental information document: Savannah River Laboratory Seepage Basins  

Energy Technology Data Exchange (ETDEWEB)

This document provides environmental information on postulated closure options for the Savannah River Laboratory Seepage Basins at the Savannah River Plant and was developed as background technical documentation for the Department of Energy`s proposed Environmental Impact Statement (EIS) on waste management activities for groundwater protection at the plant. The results of groundwater and atmospheric pathway analyses, accident analysis, and other environmental assessments discussed in this document are based upon a conservative analysis of all foreseeable scenarios as defined by the National Environmental Policy Act (CFR, 1986). The scenarios do not necessarily represent actual environmental conditions. This document is not meant to be used as a closure plan or other regulatory document to comply with required federal or state environmental regulations.

1987-03-01

95

Containment closure time following loss of cooling under shutdown conditions of YGN units 3 and 4  

Energy Technology Data Exchange (ETDEWEB)

The YGN Units 3 and 4 plant conditions during shutdown operation were reviewed to identify the possible event scenarios following the loss of shutdown cooling. The thermal hydraulic analyses were performed for the five cases of RCS configurations under the worst event scenario, unavailable secondary cooling and no RCS inventory makeup, using the RELAP5/MOD3.2 code to investigate the plant behavior. From the analyses results, times to boil, times to core uncovery and times to core heat up were estimated to determine the containment closure time to prevent the uncontrolled release of fission products to atmosphere. These data provide useful information to the abnormal procedure to cope with the event. 6 refs., 7 figs., 2 tabs. (Author)

1998-12-31

96

Structural intermediates in the assembly of taxoid-induced microtubules and GDP-tubulin double rings: time-resolved X-ray scattering.  

UK PubMed Central (United Kingdom)

We have studied the self-association reactions of purified GDP-liganded tubulin into double rings and taxoid-induced microtubules, employing synchrotron time-resolved x-ray solution scattering. The...Full Text Available

1996-05-01

97

Morphological survey of bar, lens, and ring components in galaxies: Secular evolution in galaxy structure  

International Nuclear Information System (INIS)

A morphological survey of barred galaxies is made to investigate the frequency of occurrence, nature, and size distributions of bars, lenses, inner and outer rings, and global spiral structure. The 121 brightest available barred galaxies are examined on Sky Survey copy plates, and on deeper and larger-scale plates, with the following main results.1. Lenses and inner rings are components of major importance in barred galaxies, occurring, respectively, in 54% of SBO--SBa, and 76% of SBab--SBc galaxies. Few early-type galaxies have rings; almost no late-type ones have lenses.2. There is an intimate connection between bars and lenses: in 17 of 20 galaxies with both components, the bar exactly fills the lens in one dimension.3. We suggest that lenses originate as bars, through an unknown process which makes some bars evolve away to a nearly axisymmetric state. Several properties of the proposed process are deduced. We emphasize ...

98

Dimensional metrology and positioning operations: basics for a spatial layout analysis of measurement systems  

CERN Document Server

Dimensional metrology and positioning operations are used in many fields of particle accelerator projects. This lecture gives the basic tools to designers in the field of measure by analysing the spatial layout of measurement systems since it is central to dimensional metrology as well as positioning operations. In a second part, a case study dedicated to a synchrotron storage ring is proposed from the detection of the magnetic centre of quadrupoles to the orbit definition of the ring.

2010-01-01

99

Cyclopeptide alkaloids. Synthesis of the ring system and its ion affinity  

International Nuclear Information System (INIS)

Several examples of the 14-membered, para-bridged ring system of the cyclopeptide alkaloids have been synthesized via an active ester cyclization. The yield of monomeric cyclopeptide varied from 1 to 33% and was affected by the amino acid substitution pattern and amide conformation of the linear peptide precursors. Both the synthetic models and a naturally occurring cyclopeptide alkaloid, ceanothine B, bind monovalent (Li"+) and divalent (Ca"2"+, Mg"2"+) cations. 4 figures, 1 table.

100

Replacement of nickel sealing rings by expanded graphite sealing rings -upgrading of SG primary collector flange connection  

Energy Technology Data Exchange (ETDEWEB)

One of the most loaded parts of a steam generator of VVER 440 MW type are the bolts and thread holes of the primary collector cover sealing set. The strength calculations and tensometric measurings performed during operation proved the high degree of a load on the bolts. The conditions of the stress limitation are not met in some cases according to the pertinent standards. The untightnesses at nickel rings occurred during putting the units of Jaslovske Bohunice and Dukovany nuclear power stations into operation. With regard to improve the reliability, the producer has taken measures to improve the quality of the rings and users have introduced more strict regulations for bolts tightening. Due to these measures the high reliability of the set has been obtained from point of view of the tightness, but substantial reduction of bolts and holes threads loading have not been obtained. Several years operation experience proved relatively low service ...

1997-12-31

101

Gravitational Lensing and Structural Stability of Dark Matter Caustic Rings  

CERN Document Server

Gravitational lensing by the dual cusp catastrophes of the cold dark matter (CDM) caustic rings at cosmological distances may provide the tantalizing opportunity to detect CDM indirectly, and discriminate between axions and weakly interacting massive particles (WIMPs). Caustics are places where the CDM particles are naturally focussed. Our focus is upon the caustic rings which are closed tubes whose cross-section is an elliptic umbilic catastrophe with three dual cusps. A caustic ring has a specific density profile, a specific geometry and, therefore, precisely calculable gravitational lensing signatures. The magnification monotonically increases as the line of sight approaches to the cusps where it diverges in the limit of zero velocity dispersion. In this limit, we find 37% magnification at a sample point near the outer cusps of the CDM caustic rings at cosmological distances. In the presence of ...

2005-01-01

102

Characteristic Of Induction Magnetic Field On The Laboratory Scale Superconducting Fault Current Limiter Circuit  

International Nuclear Information System (INIS)

Model construction of the laboratory scale superconducting fault current limiter circuit (SFCL) has been performed. The SFCL is fault current limiter and used as electric network security. It mainly consists of a copper coil, a superconducting ring and an iron core that are concentrically arranged. The SFCL circuit is essentially a transformer where the secondary windings are being replaced by the ring of YBa_2Cu_3O_7_-_x superconductor (HTS). The ring has critical transition temperature Tc = 92 K and critical current Ic = 3.61 A. Characterization of the SFCL circuit is simulated by ANSYS version 5.4 software. The SFCL circuit consists of load and transformer impedances. The results show that the inductions of magnet field flux in the iron core of primer windings and ring disappear to one other before fault state. It means that impedance of the transformer is zero. After the condition a ...

2004-06-01

103

A fluorescent aminolipid from a green photosynthetic bacterium  

Energy Technology Data Exchange (ETDEWEB)

A preliminary chemical characterization is presented of phosphate-free aminolipids isolation from Chlorobium limicola f. thiosulfatophilum. The lipid contains no phosphorus, glycerol, sugar, ornithine, or lysine. Ultraviolet absorption and fluorescence spectra indicate that the amino moiety of the lipid is an aromatic heterocyclic compound. Infrared spectra indicate that the lipid is a secondary or tertiary amide, and gas chromatograhic analysis of the hydrolyzed lipid shows that for each 1100 g of lipid, 1 mol of myristic acid (C/sub 14:0/) is linked in an amide bond. Acid hydrolysis of the lipid yields two fluorescent substances, A (ninhydrine positive) and B (negative), in addition to myristic acid. Proton nuclear magnetic resonance (NMR) studies indicate that substance A contains a butyl groups attached to a conjugated ring carbon, two equivalent ethyl groups attached to one or two nitrogen atoms, and two downfield protons (8.4 ppm), perhaps attached to a ...

1983-04-12

104

Quenching of the 2psub(1/2)-2psub(3/2) proton spin-orbit splitting in the Sr-Zr region  

Energy Technology Data Exchange (ETDEWEB)

The constancy in excitation energy of the lowest 2/sup +/ state in the Sr isotopes across the N=56 subshell closure is shown to result from a reduction in the 2psub(1/2)-2psub(3/2) proton spin-orbit splitting as the 2dsub(5/2) neutron orbital is filled.

1984-06-14

105

Interim Safety Basis for Fuel Supply Shutdown Facility  

Energy Technology Data Exchange (ETDEWEB)

This ISB, in conjunction with the IOSR, provides the required basis for interim operation or restrictions on interim operations and administrative controls for the facility until a SAR is prepared in accordance with the new requirements or the facility is shut down. It is concluded that the risks associated with tha current and anticipated mode of the facility, uranium disposition, clean up, and transition activities required for permanent closure, are within risk guidelines.

2000-09-07

106

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

107

Heterogeneous mechanism of nucleation in a superheated cryogenic fluid flow  

Energy Technology Data Exchange (ETDEWEB)

A model of heterogeneous mechanism of nucleation on impurity particles in a fluid volume is proposed. The particle spectrum is reproduced by solving the ''inverse'' problems on stationary outflow of a boiling parahydrogen with the use of experimental data of authors. A relation for a closure of the equation system describing a non-equilibrium outflow is obtained. It is shown that within the investigated parameter range one manages to calculate the characteristics of a stationary outflow with a satisfactory accuracy.

1984-03-01

108

Foshan. A fast track combined cycle for Guangdong  

Energy Technology Data Exchange (ETDEWEB)

To meet growth in the fast developing Pearl River Delta economic zone in China`s Guangdong province, a 270 MW oil-fired combined cycle at Foshan was built and commissioned in only 22 months from financial closure. This article describes the Foshan power station, specifications, design, procurement, construction and operating concerns. 5 figs.

1995-03-01

109

Closure of Off-Site FTP  

CERN Multimedia

To reduce the number of regular break-ins on CERN machines due to passwords exposed on the network in clear text, OFF-SITE FTP ACCESS TO CERN WILL BE BLOCKED in the CERN firewall from: Tuesday 20th January 2004 If you use ftp to access CERN computers from outside CERN then please see the link below for alternative access means and further advice: http://cern.ch/security/ftp Denise Heagerty, CERN Computer Security officer, Computer.Security@cern.ch

2004-01-01

110

Closure of Off-Site FTP  

CERN Document Server

To reduce the number of regular break-ins on CERN machines due to passwords exposed on the network in clear text, OFF-SITE FTP ACCESS TO CERN WILL BE BLOCKED in the CERN firewall from: Tuesday 20th January 2004 If you use ftp to access CERN computers from outside CERN then please see the link below for alternative access means and further advice: http://cern.ch/security/ftp Denise Heagerty, CERN Computer Security officer, Computer.Security@cern.ch

2003-01-01

111

ATP Hydrolysis in Eg5 Kinesin Involves a Catalytic Two-water Mechanism*?  

UK PubMed Central (United Kingdom)

Motor proteins couple steps in ATP binding and hydrolysis to conformational switching both in and remote from the active site. In our kinesin·AMPPPNP crystal structure, closure of the active...Full Text Available

2010-02-19

112

A comprehensive understanding of the efficacy of N-Ring hardening methodologies in SiGe HBTs  

International Nuclear Information System (INIS)

We investigate the efficacy of mitigating radiation-based single event effects (SEE) within circuits incorporating SiGe heterojunction bipolar transistors (HBTs) built with an N-Ring, a transistor-level layout-based radiation hardened by design (RHBD) technique. Previous work of single-device ion-beam induced charge collection (IBICC) studies has demonstrated significant reductions in peak collector charge collection and sensitive area for charge collection; however, few circuit studies using this technique have been performed. Transient studies performed with Sandia National Laboratory's (SNL) 36 MeV 16O microbeam on voltage references built with N-Ring SiGe HBTs have shown mixed results, with reductions in the number of large voltage disruptions in addition to new sensitive areas of low-level output voltage disturbances. Similar discrepancies between device-level IBICC results and circuit measurements are found for the case of digital shift ...

2010-07-19

113

U Orionis: the evolution and proper motion of the OH maser envelope  

International Nuclear Information System (INIS)

The Jodrell Bank MERLIN array was used to map the OH 1665-and 1667-MHz masers in the circumstellar envelope of U Orionis in 1984, 1986 and 1987. The OH masers lie within a region of extent 130 x 180 AU"2, and have complex distribtuions which are different for each line and polarization. The masers show clumpy structures with a typical clump size of #approx# 25 AU. The strongest emission is from a ring of radius 60 AU which we interpret as part of an expanding, tilted torus. Proper motions have been measured for the OH masers on the ring. The ring has a proper motion of 5.4#+-#1.4 mass yr"-"1 corresponding to a transverse expansion velocity of #approx# 7 km s"-"1 for the period-luminosity distance of U Orionis of 260 pc. (author).

114

The duke XUV FEL storage ring facility  

Energy Technology Data Exchange (ETDEWEB)

In this paper we present status and developments of the Duke storage ring facility. The Duke storage ring facility provides the unique combination of phase-locked light sources ranging from high power OK-4 XUV FEL to quasimonochromatic {gamma}-ray beam and IR/X-ray spontaneous radiation. The XUV OK-4 FEL, which is collaborative project with BlNP, Novosibirsk, is in operation since November, 1996. The OK-4 UV FEL is also used for production of nearly monochromatic {gamma}-ray s with tunable energy. We present the results of UV lasing with the OK4 FEL and selected results of its applications. We will discuss our future plans for extension of this source and status of the construction of dedicated used facility adjacent to the FEL building. (author)

1998-11-01

115

The controlled creation of a maximally entangled state between a SQUID ring and a single electromagnetic field mode  

International Nuclear Information System (INIS)

We consider a SQUID ring inductively coupled to an electromagnetic field mode, both treated quantum mechanically. We demonstrate a method for creating a maximally entangled state between the ring and the field mode. Our method utilises a non-adiabatic external magnetic flux pulse to move into and out of a transition region. Hence, our approach is fundamentally different to techniques based on Landau-Zener tunnelling that can also be used to achieve similar results. Our analysis is extended to include the effects of coupling the system to a dissipative environment. With this model we show that although such an environment makes a noticeable difference to the time evolution of the system, it need not destroy the entanglement of this coupled system over time scales required for quantum technologies.

2010-07-01

116

The cohomology ring of the GKM graph of a flag manifold of classical type  

CERN Document Server

If a closed smooth manifold $M$ with an action of a torus $T$ satisfies certain conditions, then a labeled graph $\\mG_M$ with labeling in $H^2(BT)$ is associated with $M$, which encodes a lot of geometrical information on $M$. For instance, the "cohomology" ring $\\mHT^*(\\mG_M)$ of $\\mG_M$ is defined to be a subring of $\\bigoplus_{v\\in V(\\mG_M)}H^*(BT)$, where $V(\\mG_M)$ is the set of vertices of $\\mG_M$, and is known to be often isomorphic to the equivariant cohomology $H^*_T(M)$ of $M$. In this paper, we determine the ring structure of $\\mHT^*(\\mG_M)$ when $M$ is a flag manifold of classical type directly without using the fact that $\\mHT^*(\\mG_M)$ is isomorphic to $H^*_T(M)$.

2011-01-01

117

Simulation of a storage ring Free Electron Laser with mapping algorithm for distribution functions  

International Nuclear Information System (INIS)

A model for the simulation of the time dependent behavior and the analysis of the equilibrium of the coupled system of storage ring and Free Electron Laser (FEL) is presented. The analysis comprises both amplifier and oscillator FEL. Bunch lengthening and energy widening due to wake forces are taken into account in a self-consistent way. The method is based on a mapping algorithm for means and correlations of the electron distribution function, pioneered by K. Hirata. The evolution of the laser field in the oscillator FEL is described by K. Hirata. The evolution of the laser field in the oscillator FEL is described by supermodes. The model is used to simulate an FEL in a small 500 MeV storage ring with 100 m circumference. Typical values for the output power, spatial, and spectral characteristics of the emitted radiation are presented.

1991-05-06

118

Nuclei with protrusions - tailed nuclei - and radiation cytogenetic markers in X-irradiated lymphocytes in vitro  

International Nuclear Information System (INIS)

The results of an investigation into tailed nuclei (TN) and features of dose dependence on frequency of the binuclear cells with TN in human lymphocyte cultures by cytogenetic block method upon X-ray radiation dose are presented. The frequencies of metaphases with dicentric and ring chromosomes are investigated concurrent with TN formed upon completion of first postradiation mitosis. Frequency of the appearance of binuclear cells with nuclei having outgrowth into the cytoplasmic space and arises after first mitosis in human lymphocyte culture is linear-square dependent on the X-irradiation at doses from 0.0 to 4.0 Gy. Positive correlation between frequency of cells with tailed nuclei and frequency of metaphases of first mitosis having dicentric and rings was established. Apparently, formation such TN is connected with dicentric and rings

119

Five centuries of Central European temperature extremes reconstructed from tree-ring density and documentary evidence  

British Library Electronic Table of Contents (United Kingdom)

Future climate change will likely influence the frequency and intensity of weather extremes. As such events are by definition rare, long records are required to understand their characteristics, drivers, and consequences on ecology and society. Herein we provide a unique perspective on regional-scale temperature extremes over the past millennium, using three tree-ring maximum latewood density (MXD) chronologies from higher elevations in the European Alps. We verify the tree-ring-based extremes using documentary evidences from Switzerland, the Czech Republic, and Central Europe that allowed the identification of 44 summer extremes over the 1550-2003 period. These events include cold temperatures in 1579, 1628, 1675, and 1816, as well as warm ones in 1811 and 2003. Prior to 1550, we provide ...

2010-01-01

120

Challenges for Lithuania: Ignalina NPP Early Closure  

International Nuclear Information System (INIS)

As a condition of accession into the European Union (EU), Lithuania is committed to the closure and decommissioning of Ignalina NPP comprising two RBMK-1500 reactor units (Fig. 1). It was agreed in a special protocol to the Accession Treaty that, in return for adequate EU financial assistance, Unit 1 would be closed before 2005 and Unit 2 by the end of 2009. The first unit was duly shut down on December 31, 2004. Lithuania, which has borders with Russia (Kaliningrad territory), Poland, Latvia and Belarus, spent fifty years as part of the Soviet Union and was deeply integrated into its economy and electrical infrastructure. At the break-up of the USSR, Lithuania inherited electricity generating capacity designed to supply the north-west region including ownership of Ignalina NPP located in the north-east of the country. Ignalina NPP Unit 1 was commissioned in 1983, Unit 2 in 1987; the planned lifespan of each unit was 30 years. Construction of a third unit was ...

2008-01-01

121

The Dixmier-Moeglin equivalence and a Gel'fand-Kirillov problem for Poisson polynomial algebras  

CERN Document Server

The structure of Poisson polynomial algebras of the type obtained as semiclassical limits of quantized coordinate rings is investigated. Sufficient conditions for a rational Poisson action of a torus on such an algebra to leave only finitely many Poisson prime ideals invariant are obtained. Combined with previous work of the first-named author, this establishes the Poisson Dixmier-Moeglin equivalence for large classes of Poisson polynomial rings, such as semiclassical limits of quantum matrices, quantum symplectic and euclidean spaces, quantum symmetric and antisymmetric matrices. For a similarly large class of Poisson polynomial rings, it is proved that the quotient field of the algebra (respectively, of any Poisson prime factor ring) is a rational function field $F(x_1,...,x_n)$ over the base field (respectively, over an extension field of the base field) with $\\{x_i,x_j\\}= \\lambda_{ij} x_ix_j$ for ...

2007-01-01

122

Simulations of a ring resonator free-electron laser  

International Nuclear Information System (INIS)

In this paper, a relatively high gain (#approx =# 25 to 40 percent) free-electron laser (FEL) with an optical ring resonator is simulated using the code FELEX. The laser system corresponds to the ''burst mode'' FEL scheduled for operation at Boeing Aerospace Company in 1988. The ring consists of paraboloids, grazing incidence by hyperboloids, and a grating rhomb. The wiggler is 5 m in length and has an adjustable taper, while the electron beam is produced by an RF linac. The optical elements of the ring together with the FEL interaction in the wiggler are modeled in three spatial dimensions to investigate the system from start-up to saturation. Both single frequency and finite pulse simulations are performed. The study illustrates the necessity of mode matching the loaded resonator to maximize the extraction efficiency. The mode matching is necessary because the FEL interaction significantly alters the optical beam focus ...

124

Reading strategies in Stargardt's disease with foveal sparing  

UK PubMed Central (United Kingdom)

BackgroundSubjects with a ring scotoma can use two retinal loci, a foveal and a peripheral, for reading. Our aim was to investigate the relative use of both retinal loci as a function...Full Text Available

125

ROMP from ROMP: A New Approach to Graft Copolymer Synthesis  

UK PubMed Central (United Kingdom)

A new strategy is presented for the synthesis of graft copolymers using only the ring-opening metathesis polymerization (ROMP). From a ROMP-derived main chain, pendant maleimide functional groups...Full Text Available

2009-06-23

126

Potassium deposition on a thiophene-terminated alkanethiol monolayer  

International Nuclear Information System (INIS)

Potassium deposition in ultrahigh vacuum on 12-(3-thienyl)dodecanethiol monolayers assembled on gold surfaces has been investigated using X-ray and ultraviolet photoelectron spectroscopies (XPS and UPS). Angle-resolved XPS indicates that initially deposited potassium penetrates the self-assembled monolayer (SAM) and diffuses to the SAM/Au interface. Even after large metal doses, the presence of thiophene ring valence electronic states in the UPS spectra confirms that most of the thiophene rings (at the SAM/vacuum interface) are not covered by potassium. The binding energy shifts of the thiophene ring valence states and the C1s and thiophene S2p peaks, referenced to the Fermi level, are due to the work function changes of the gold substrate. This indicates that these electronic states are pinned to the vacuum level, in contrast to the thiolate S2p orbital, which is pinned to the Fermi level. For large potassium doses, the ...

2009-05-01

127

Performance of Buried Pipe Installations, Summary.  

Science.gov (United States)

The goal of this research project was to determine the eff ects of geometric and mechanical parameters characterizing the soil-structure interaction developed in a buried pipe installation. Parameters such as pipe ring stiff ness, bedding thickness, trenc...

2010-01-01

128

PHARMACOLOGICAL TREATMENTS FOR TINNITUS: NEW AND OLD  

UK PubMed Central (United Kingdom)

Subjective tinnitus, the phantom ringing or buzzing sensation that occurs in the absence of sound, affects 12–14% of adults; in some cases the tinnitus is so severe or disabling that...Full Text Available

2009-01-01

129

On the bending response of Kevlar 49/epoxy beams and rings  

Energy Technology Data Exchange (ETDEWEB)

Kevlar 49/epoxy laminates often exhibit substantial material nonlinearity when subjected to bending. This is a consequence of the yeild-like behavior of a Kevlar 49/epoxy lamina in fiber-directed compression. In this paper, analyses that utilize a simple idealization of compressive yielding are described and calculated results for Kevlar 49 reinforced beams and rings are compared with available data. First, results of a finite element analysis of a thin, unidirectionally reinforced ring subjected to diametral compression are presented. This analysis uses beam elements that incorporate linear tensile and elastic-perfectly plastic compressive behavior. Then a method used to analyze quasi-isotropic beams tested in four-point bending is discussed. This finite element analysis uses a layered shell element with a lamina constitutive model that permits elastic-perfectly plastic response to fiber-directed compression, but otherwise assumes linear ...

1988-05-01

130

NASA Aeronautical Engineenng Aera 3ring Aeronautical Engineenng  

Science.gov (United States)

for an Air Force Manufacturing technology program whose aim is the establishment of organic matrix ...... display considerations for advanced energy/flight management sys- ...... Future System - The Roadmap of the System of the Future - ...... data storage units, pilot's guidance indicators, and a quick look ...

131

Minimizing energy consumption of accelerators and storage ring facilities  

Science.gov (United States)

The discussion of energy usage falls naturally into three parts. The first is a review of what the problem is, the second is a description of steps that can be taken to conserve energy at existing facilities, and the third is a review of the implications of energy consumption on future facilities.

132

Metallic seals offer improved resilience  

International Nuclear Information System (INIS)

Metallic O-ring or Helicoflex seals can prevent relaxation and provide greater resilience than composite seals, helping to keep joints leaktight. Their characteristics and applications in the nuclear industry are outlined. (Author).

133

Mechanism of the dissolution of coals in a mixture of concentrated sulfuric and nitric acids  

British Library Electronic Table of Contents (United Kingdom)

In this work, coals of various ranks were dissolved in an acid melange. With the use of IR spectroscopy, it was found that the mechanism of coal dissolution consists in the grafting of polar groups to the peripheral benzene rings of graphite-like systems.

2011-01-01

134

Impact of the 3,6,9-Trioxadecyloxy Group on Desazadesferrithiocin Analogue Iron Clearance and Organ Distribution  

UK PubMed Central (United Kingdom)

The impact of introducing a 3,6,9-trioxadecyloxyl group at various positions of the desazadesferrithiocin (DADFT) aromatic ring on iron clearance and organ distribution is described. Three DADFT...Full Text Available

2007-07-12

135

I. Cyclopeptide Alkaloids; II. Phycocyanobilipeptides.  

Science.gov (United States)

Several examples of the 14-membered, para-bridged ring system of the cyclopeptide alkaloids have been synthesized via an active ester cyclization. The yield of monomeric cyclopeptide varied from 1 to 33% and was affected by the amino acid substitution pat...

1979-01-01

136

Hydroxylation of 3-Nitrotyrosine and Its Derivatives by Gamma Irradiation  

Science.gov (United States)

... the hydroxyl group with the benzene ring. The molar extinction coefficients for the various species at their respective absorption ... Glya Recorded by 1H-NMR Spectroscopy TABLE 2 Molar Extinction Coeff...

137

Episodic mass loss in binary evolution to the Wolf-Rayet phase: Keck and HST proper motions of RY Scuti's nebula  

CERN Document Server

Binary mass transfer via Roche-lobe overflow (RLOF) is a key channel for producing stripped-envelope Wolf-Rayet (WR) stars and may be critical to account for SN Ib/c progenitors. RY Scuti is an extremely rare example of a massive binary star caught in this brief but important phase. Its toroidal nebula indicates equatorial mass loss during RLOF, while the mass-gaining star is apparently embedded in an opaque accretion disk. RY Scuti's toroidal nebula has two components: an inner ionised double-ring system, and an outer dust torus that is twice the size of the ionised rings. We present two epochs of Lband Keck NGS-AO images of the dust torus, plus three epochs of HST images of the ionised gas rings. Proper motions show that the inner ionised rings and the outer dust torus came from two separate ejection events roughly 130 and 250 yr ago. This suggests that RLOF in massive contact binaries can be ...

2011-01-01

138

Environment influences on the aromatic character of nucleobases and amino acids  

UK PubMed Central (United Kingdom)

Geometric (HOMA) and magnetic (NICS) indices of aromaticity were estimated for aromatic rings of amino acids and nucleobases. Cartesian coordinates were taken directly either from PDB files deposited...Full Text Available

2010-11-01

139

Emergency core cooling device  

International Nuclear Information System (INIS)

Purpose: To effectively cool the reactor core in a steam atmosphere by upwardly directing several of spray nozzles attached to a ring header thereby increasing the flying distance of the spray. Constitution: Ring headers in two upper and lower stages are disposed above the outer circumference of a reactor core and each of the ring headers is mounted with spray nozzles. Among the spray nozzles, at least several nozzles mounted to the ring header at the lower stage are directed such that the center axis for each of the nozzle is raised above the horizontal axis and other several nozzles are mounted with the nozzle center axis directed downwardly from the horizontal axis. Accordingly, even if collapsing phenomenon occurs in the jetting stream due to the condensation in the steams that forms the operation atmosphere of the reactor core spray cooling device, a sufficient amount of emergency cooling water can ...

1983-03-09

140

Biphasic targeting and cleavage furrow ingression directed by the tail of a myosin II  

UK PubMed Central (United Kingdom)

Cytokinesis in animal and fungal cells utilizes a contractile actomyosin ring (AMR). However, how myosin II is targeted to the division site and promotes AMR assembly, and how the AMR coordinates with...Full Text Available

2010-12-27

141

Using ICCD as a fast optical switch to measure harmonic super-radiation from an optical klystron in a storage ring  

International Nuclear Information System (INIS)

An optical klystron is built in the 800 MeV electron storage ring at University of Science and Technology of China for harmonic super-radiation generation. In single bunch operation mode the repetition rate of the spontaneous radiation pulses is about 4.533 MHz, and the repetition rate of the seed laser pulses is about 3 Hz, while the radiation pulse duration is 300 ps. For measuring harmonic radiation a high on/off ratio ICCD is used as an optical switch to reject spontaneous radiation pulses of high repetition rate

2001-07-01

142

Ultrasensitive laser isotope analysis in an ion-storage ring  

Energy Technology Data Exchange (ETDEWEB)

We propose a novel method for ultrasensitive isotope analysis that combines magnetic mass selection, resonant charge-exchange neutralization, and resonant laser ionizaion. Our method attains high isotopic abundance selectivity by means of continuous multistage separation of ions stored in a small ring. For the environmentally interesting case of /sup 90/Sr versus /sup 88/Sr we estimate that sensitivity better than 10/sup -15/ for a throughput of 10/sup 13/ atoms/sec and an efficiency (after the ion source) greater than 10% are readily achievable.

1985-09-01

143

Third harmonic lasing in a storage ring free-electron laser  

International Nuclear Information System (INIS)

We report the first experimental achievement of a storage ring free-electron laser (FEL) oscillation on the third harmonic in the near-infrared region. The FEL gain was evaluated as 0.029% per mA. The measured linewidth of the third-harmonic FEL was less than that of the fundamental FEL, and the measured pulse width of the third-harmonic FEL was wider than that of the fundamental FEL. A higher-harmonic FEL should be developed not only to enhance the wavelength region of the FEL but also to vary the characteristics of an FEL micropulse. (author)

2010-09-01

144

Solution conformations of CaCl sub 2 and Ca(NO sub 3 ) sub 2 complexes of chiral tetramethyl 18-crown-6 macrocycles: A 1D and 2D sup 1 H and sup 13 C NMR investigation  

Energy Technology Data Exchange (ETDEWEB)

One- and two-dimensional NMR techniques have been used to investigate the solution structures of (2S,6S,11S,15S)-2,6,11,15-tetramethyl-1,4,7,10,13,16-hexaoxacyclooctadecane (I) and (2R,3R,11R,12R)-2,3,11,12-tetramethyl-1,4,7,10,13,16-hexaoxyacyclooctadecane (II) macrocycle complexes of CaCl{sub 2} and Ca(NO{sub 3}){sub 2} in CDCl{sub 3}. Previous chiroptical studies of these and similar crown complexes by circularly polarized luminescence (CPL), total luminescence (TL), and circular dichroism (CD) spectroscopy have shown that the macrocycle asymmetric carbons in these complexes constrain the ring such that the sense of the ring twist in the S chiral ring complexes is opposite to that in the R chiral ring complexes. These studies have also shown that there is an added chirality element in the di- and trivalent (alkaline earth and lanthanide metal, respectively) nitrate complexes of I and II associated ...

1989-10-04

145

Proceedings of the impedance and bunch instability workshop  

Energy Technology Data Exchange (ETDEWEB)

This report discusses the following topics: impedance and bunch lengthening; single bunch stability in the ESRF; a longitudinal mode-coupling instability model for bunch lengthening; high-frequency behavior of longitudinal coupling impedance; beam-induced energy spreads at beam-pipe transitions; on the calculation of wake functions using MAFIA-T3 code; preliminary measurements of the bunch length and the impedance of LEP; measurements and simulations of collective effects in the CERN SPS; bunch lengthening in the SLC damping rings; and status of impedance measurements for the spring-8 storage ring.

1990-04-01

146

Perturbing the ground ring of 2D string theory  

Energy Technology Data Exchange (ETDEWEB)

In this paper, the authors use free field techniques in D = 2 string theory t calculate the perturbation of the special state algebras when the cosmological constant is turned on. In particular, the authors find that the 'ground cone' preserved by the ring structure is promoted to a three-dimensional hyperboloid as conjectured by Witten. On the other hand, the perturbed (1,1) current algebra of moduli deformations is computed completely, and no simple geometrical interpretation is found. The authors also quote some facts concerning the Liouville matrix a model dictionary in this class of theories.

1992-12-10

147

Lasing below 200 nm in the NIJI-IV compact storage-ring-based free electron laser  

International Nuclear Information System (INIS)

Laser gain of the NIJI-IV compact storage-ring-based Free Electron Laser (FEL) system at AIST reached #approx#9% at 200 nm for an average beam current of 16.3 mA. In addition to such a drastic gain enhancement, improvement of the laser-cavity performance has led to successful FEL lasing in the vacuum ultraviolet below 200 nm even in a compact system. Temporal and spectral characteristics of the NIJI-IV FEL were examined around 200 nm. FEL performance will be briefly discussed from the application point of view.

2004-08-01

148

Inner ring structures in galaxies as distance indicators. III. Distances to 453 spiral and lenticular galaxies  

International Nuclear Information System (INIS)

The diameters d/sub r/ of inner ring structures in disk galaxies are used as geometric distance indicators to derive the distances of 453 spiral and lenticular galaxies, mainly in the distance interval 4<#delta#<63 Mpc. The diameters are weighted means from the catalogs to Kormendy, Pedreros and Madore, and the authors. The distances are calculated by means of the two- and three-parameter formulae of Paper II; the adopted mean distance moduli #mu#"0(r) have mean errors from all sources of 0.6--0.7 mag for the well-observed galaxies.

149

Free relations for matrix invariants in the modular case  

British Library Electronic Table of Contents (United Kingdom)

A classical linear group GJ between the graded ring S= d=0^~Sd, where Sd is the character group of the symmetric group Sd, and the inverse limit J with respect to n of rings of symmetric polynomials in n variables. As a consequence, we complete the description of relations between generators for O(n)-invariants as well as the description of relations for invariants of mixed representations of quivers. We also obtain an independent proof of the result that the ideal of free relations for GL(n)-invariants is zero, which was proved by Donkin in [S. Donkin, Invariant functions on matrices, Math. Proc. Cambridge Philos. Soc. 113 (1993) 23-43].

2012-01-01

150

Experience in use of thermal insulation compounds produced by NPP Tekhmet at Ruspolimet  

British Library Electronic Table of Contents (United Kingdom)

Pilot industrial-scale testing of TSK-25 and TSK-10 compounds produced by NPP Tekhmet has been performed at Ruspolimet for siphon casting of 0.7?1.5-metric-ton ingots which are broader on the top (?flowers??) used for production of all-rolled rings; this is as an alternative to the existing process of pouring the steel into molds lubricated with petrolatum. The evaluation tests led to recommendation of the TSK-10 compound for industrial-scale testing; use of this compound enabled the petrolatum-lubricated steel casting process to be abandoned, thereby improving working conditions, and reducing rejects of the all-rolled ring products.

2009-01-01

151

Summary of the Waste Management Programs at uranium recovery facilities as they relate to the 40 CFR Part 192 standards  

International Nuclear Information System (INIS)

This study evaluates the degree to which surface impoundments at licensed facilities comply with significant changes in NRC requirements initiated by enactment of EPA's final environmental standards for uranium recovery facilities (40 CFR Part 192). Impoundment liner requirements, ground-water protection standards, ground-water monitoring and corrective action programs, and site closure standards are the most significant regulatory modifications. The compliance status of 30 conventional mills and 31 in-situ mines is determined from a review of Nuclear Regulatory Commission and agreement state docket files through November, 1983. Results of this review show that a majority of conventional uranium mill tailings management systems are deficient with respect to liner requirements for new impoundments or proposed expansions to existing impoundments, as well as with respect to some aspects of ground-water monitoring and compliance programs. Furthermore, the status of ...

152

RCRA closure of the Building 3001 Storage Canal  

Energy Technology Data Exchange (ETDEWEB)

The 3001 Storage Canal is located under portions of Buildings 3001 and 3019 at Oak Ridge National Laboratory (ORNL) and has a capacity of approximately 62,000 gallons of water. The term canal has historically been used to identify this structure, however, the canal is an in-ground reinforced concrete structure satisfying the regulatory definition of a tank. From 1943 through 1963, the canal in Building 3001 was designed to be an integral part of the system for handling irradiated fuel from the Oak Ridge Graphite Reactor. Because one of the main initial purposes of the reactor was to produce plutonium for the chemical processing pilot plant in Building 3019, the canal was designed to be the connecting link between the reactor and the pilot plant. During the war years, natural uranium slugs were irradiated in the reactor and then pushed out of the graphite matrix into the system of diversion plates and chutes which directed the fuel into the deep pit of the canal. After shutdown of the ...

1992-09-01

153

Temporary endovascular control of a bleeding aortoenteric fistula by transcatheter coil embolization.  

Science.gov (United States)

A 67-year-old man presented with gastrointestinal bleeding resulting from a fistula between the aortic stump and the fourth part of the duodenum 14 months after an axillobifemoral bypass, graft excision, and aortic stump closure for aortic graft infection. The patient initially refused any attempt at definitive surgical treatment so coil embolization of the aortic stump was performed via a brachial approach. Coil embolization may be a useful adjunct in the management of such difficult problems. This approach may buy time and allow careful planning of a definitive treatment or may serve as a palliative procedure in inoperable patients. PMID:15947052

2005-06-01

154

Radiological criteria, potential and limitations of ADTT at closing nuclear fuel cycle  

International Nuclear Information System (INIS)

Closure of nuclear fuel cycle is considered as a way to reduce the hazards of nuclear power industry waste. The potential and prospects of different technologies and installations including ADTT in solving this problem are discussed. A new relative criterion is proposed to assess the dangers of the waste. Equilibrium mode approximation is used in the estimates. It is shown that irretrievable losses of actinides do not depend on relative intensity of burning. Neutron economy of accelerator-driven blankets is considered and an expression is derived for transmutation value of 'external' neutrons. 8 refs., 2 tabs.

1996-06-01

155

Modeling of feed water check valves using RELAP5; Modellierung von Speisewasserrueckschlagventilen in RELAP5  

Energy Technology Data Exchange (ETDEWEB)

Westinghouse Electric Germany GmbH has developed fluid dynamic models for medium-actuated armatures using the thermal hydraulic code RELAP5 in order to reach a more realistic description of the armature behavior including fluid-structure interactions in case of transient flow conditions in piping systems. The contribution is concerned with the modeling of damped check valves. The model allows the description of the behavior during opening and closure of a check armature. The calculated results show good agreement with the available measured data.

2009-07-01

156

Grid-controlled plasma cathodes  

International Nuclear Information System (INIS)

Experiments are described on a plasma cathode with biased grids to prevent entry of ions into the electron extraction gap. The cathode has potential applications to the generation of high-current pulsed electron beams. Operation at 20 A/cm"2 is theoretically possible. The source combines the low average power consumption of a plasma cathode with many of the attractive features of thermionic cathodes, such as space-charge-limited extractor gap electron flow, fast turn-on, and no diode closure. Initial experiments are reported at the 2 A/cm"2 level for pulse lengths to 160 #mu#s.

157

Correction of skeletal Class II-anterior deep bite and prominent chin by forced surgical rotation of the mandible  

British Library Electronic Table of Contents (United Kingdom)

The purpose of this paper is to describe a technique of forced surgical rotation of the mandible used in skeletal Class II patients with deep bite and prominent chin. Posterior occlusal composite onlays combined with preoperative orthodontic treatment without anterior intrusion increase the posterior rotational component of the surgical mandibular advancement, when removed during operation. This manoeuvre allows for the surgical closure of the posterior open bite, while anteriorly the deep bite is opened. This technique avoids bimaxillary rotation surgery with dorsal impaction in mild to moderate cases. In any case, a chin setback osteotomy with compromised aesthetics can be avoided.

2010-01-01

158

Aluminum hydroxide issue closure package  

Energy Technology Data Exchange (ETDEWEB)

Aluminum hydroxide coatings on fuel elements stored in aluminum canisters in K West Basin were measured in July and August 1998. Good quality data was produced that enabled statistical analysis to determine a bounding value for aluminum hydroxide at a 99% confidence level. The updated bounding value is 10.6 kg per Multi-Canister Overpack (MCO), compared to the previously estimated bounding value of 8 kg/MCO. Thermal analysis using the updated bounding value, shows that the MCO generates oxygen concentrate that are below the lower flammability limits during the 40-year interim storage period and are, therefore, acceptable.

1998-08-26

159

A study on the design method of multi tunnels in geological disposal facility  

International Nuclear Information System (INIS)

In the geological disposal facility of the high-level radioactive waste, a group of galleries is designed in parallel at the depth of more than 300 m below surface. This is an unprecedented structure in the field of conventional engineering, and it is necessary to take this characteristic into consideration in the design of the galleries. In the geological disposal facility, as well as ensuring the dynamic stability of the gallery during construction and operational periods, it is necessary to evaluate the EDZ adequately for long-term stability after the closure. In this study, analysis of the 'multi tunnels model' which represents the whole gallery group was performed and the results about the outbreak behavior of EDZ were summarized. (author)

2008-01-01

160

Modeling of turbulent bubbly flows; Modelisation des ecoulements turbulents a bulles  

Energy Technology Data Exchange (ETDEWEB)

The two-phase flows involve interfacial interactions which modify significantly the structure of the mean and fluctuating flow fields. The design of the two-fluid models adapted to industrial flows requires the taking into account of the effect of these interactions in the closure relations adopted. The work developed in this thesis concerns the development of first order two-fluid models deduced by reduction of second order closures. The adopted reasoning, based on the principle of decomposition of the Reynolds stress tensor into two statistically independent contributions turbulent and pseudo-turbulent parts, allows to preserve the physical contents of the second order relations closure. Analysis of the turbulence structure in two basic flows: homogeneous bubbly flows uniform and with a constant shear allows to deduce a formulation of the two-phase turbulent viscosity involving the characteristic scales of bubbly ...

2005-03-15

161

Laparoscopic classification and treatment of the impalpable testis.  

Science.gov (United States)

Laparoscopic orchiopexy has gained popularity in recent years. However, the decision when to perform one-stage laparoscopic orchiopexy without division of the spermatic vessels versus initial ligation of the spermatic vessels followed later by orchiopexy is not clear. A new laparoscopic classification to facilitate decision-making during laparoscopy, according to the position of the impalpable testis and the relation of the spermatic vessels and vas deferens to the internal ring, with a management protocol based on this classification is presented. Over a 2-year period, a total of 37 boys with 52 impalpable gonads underwent a laparoscopic procedure. Four laparoscopic types of testis were noted: type I: no testis visualized; type II: a testis seen at the internal ring with the vas and vessels looping to the internal ring; type III: testis at the internal ring, with vas and vessels going to the testis ...

1999-01-01

162

Effects of ligation type and method on the resistance to sliding of novel orthodontic brackets with second-order angulation in the dry and wet states.  

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 ...

2003-08-01

163

ESR study of the aziridine and azetidine radical cations: evidence for the C...C ring-opened aziridine radical cation  

International Nuclear Information System (INIS)

The radical cations from aziridine and azetidine have been characterized by ESR spectroscopy following their generation in the solid state by #gamma# irradiation of dilute solutions of the parent compounds in the CFCl_3 matrix at 77 K. The ESR parameters of the azetidine radical cation are typical of those for nitrogen-centered amine radical cations such as Me_2NH*"+. On the other hand, the radical cation formed from aziridine has very different ESR parameters that compare closely to those for the isoelectronic C...C ring-opened form of the oxirane radical cation and the allyl radical. The radical cation formed from azetidine is therefore assigned a ring-closed structure with the unpaired electron in a 2p/sub z/ orbital on nitrogen perpendicular to the ring plane, whereas the cation from aziridine is an allylic C...C ring-opened planar isomer with the unpaired electron in a nonbonding #pi# orbital ...

164

ESR study of the aziridine and azetidine radical cations: evidence for the C. C ring-opened aziridine radical cation  

Energy Technology Data Exchange (ETDEWEB)

The radical cations from aziridine and azetidine have been characterized by ESR spectroscopy following their generation in the solid state by ..gamma.. irradiation of dilute solutions of the parent compounds in the CFCl/sub 3/ matrix at 77 K. The ESR parameters of the azetidine radical cation are typical of those for nitrogen-centered amine radical cations such as Me/sub 2/NH*/sup +/. On the other hand, the radical cation formed from aziridine has very different ESR parameters that compare closely to those for the isoelectronic C...C ring-opened form of the oxirane radical cation and the allyl radical. The radical cation formed from azetidine is therefore assigned a ring-closed structure with the unpaired electron in a 2p/sub z/ orbital on nitrogen perpendicular to the ring plane, whereas the cation from aziridine is an allylic C...C ring-opened planar isomer with the unpaired electron in a nonbonding ...

1986-05-22

165

The potential of the baobab (Adansonia digitata L.) as a proxy climate archive  

Energy Technology Data Exchange (ETDEWEB)

The large girth and immense size of the baobab has caused many to speculate about its age. Unfortunately reliable age estimates cannot be determined from growth rates as the girth varies in response to different moisture regimes. In a similar way, ages cannot be determined from ring-width measurements or X-ray densitometry as the absorbent nature of the soft fibrous wood and distortion upon drying prevent the application of these techniques. The Southern Hemisphere bomb radiocarbon curve was used to demonstrate that the rings of a recently-fallen baobab (Adansonia digitata L.) from Kruger National Park appear to be annual. The detrended C isotope values of finely-ground wholewood from another baobab specimen were found to be highly associated with January precipitation (r = 0.72; p < 0.01). This study demonstrates that high resolution information about past climates may be obtained by analysing the C isotope values from baobab samples ...

2006-10-15

166

The potential of the baobab (Adansonia digitata L.) as a proxy climate archive  

International Nuclear Information System (INIS)

The large girth and immense size of the baobab has caused many to speculate about its age. Unfortunately reliable age estimates cannot be determined from growth rates as the girth varies in response to different moisture regimes. In a similar way, ages cannot be determined from ring-width measurements or X-ray densitometry as the absorbent nature of the soft fibrous wood and distortion upon drying prevent the application of these techniques. The Southern Hemisphere bomb radiocarbon curve was used to demonstrate that the rings of a recently-fallen baobab (Adansonia digitata L.) from Kruger National Park appear to be annual. The detrended C isotope values of finely-ground wholewood from another baobab specimen were found to be highly associated with January precipitation (r = 0.72; p < 0.01). This study demonstrates that high resolution information about past climates may be obtained by analysing the C isotope values from baobab samples even ...

2006-10-01

167

The Bunch Injection Controller for the PEP-II Storage Rings  

CERN Document Server

The PEP-II storage rings at SLAC each have 3492 'buckets' into which electrons and positrons can be injected into the high- and low-energy rings. Equipment to measure the currents of all the individual buckets was originally provided by the Lawrence Berkeley Laboratory and is implemented in VXI-based hardware. Data from this equipment as well as high precision direct current measurement provide the hard data for the Bunch Injection Controller. A large number of parameters determined by injection design considerations as well as set by operators for different circumstances are also used by the software algorithms to determine the desired bucket injection order and charge quantity for each injection pulse. These requests are then passed on to the venerable SLAC master pattern generator, which provides beams for other applications as well. This highly visible and highly successful system is implemented using the EPICS toolkit, and fits well into ...

2001-01-01

168

Study on wavelength shortening and upgrading of the free electron laser (FEL)  

International Nuclear Information System (INIS)

This study is a task of ''Comprehensive study'' in ''nuclear energy basic technology research'', which is promoted under cooperation of four research institutes. The Electrotechnical Laboratory conducted, in 1991 in the first period of colaboration, on successful oscillation at visible region (598 nm) as the first case in Japan, construction of small type accumulation ring NIJI-IV for FEL, successful oscillation of visible range from 595 to 488 nm by installing optical krystron with maximum frequency in the world, and successful emittance lowering of accumulation beam by wide improvement of the ring. In the optical resonator, studies on minute loss measuring technique and on recovery from mirror deterioration were promoted. In the second period started from fiscal year of 1994, studies on FEL oscillation technique in short wavelength and upgrading of FEL corresponding to a frontier area were started, to succeed an oscillation experiment at 350 ...

169

Rotation seismic sensor and its calibration; Kaiten seibun jishinkei no shisaku to kando no kentei  

Energy Technology Data Exchange (ETDEWEB)

Sensor has been developed for the measurement of seismic wave rotary components. The vertical axis rotary component sensor is constituted of four L22Ds, similar to each other in performance, fixed in a ring formation on a metal bed. The ring is 22cm in diameter, and the four coils are connected so that their outputs will be added up. A horizontal axis rotary component sensor is built in the similar way. The rotary component sensors are all connected to a spectrum analyzer for the measurement of micromotions. It is found that the four-L22D combination can detect a rotary component of 335mV/deg/s. The sensor can detect both vertical and horizontal components with roughly the same sensitivity. A ring-form combination of conventional electromagnetic seismometers, though only as a temporary expedient, can perform high-resolution detection of rotary components and determine the absolute values of earthquakes or noise levels. In ...

1997-05-27

170

Radioisotopic techniques for noninvasive detection of platelet deposition in bovine-tissue mitral-valve prostheses and in vitro quantification of visceral microembolism in dogs  

International Nuclear Information System (INIS)

Platelet deposition on bovine pericardial-tissue mitral-valve prostheses in 11 dogs was observed noninvasively by use of "1"1"1In-labeled platelets and quantified after sacrifice at one (n . 3), 14 (n . 3), and 30 (n . 5) days postimplantation (300-400 microCi of labeled platelets having been injected 24 hours previously). Thrombosis on the sewing ring and pericardial leaflets at one and 14 days and on the leaflets at 30 days was delineated in scintiphotos. In vitro quantification (% injected dose) indicated that the leaflets, sewing ring, and perivalvular tissue retained 0.904% of labeled platelets at one day postimplantation, 0.198% at 14 days, and 0.040% at 30 days. Platelet half-life was reduced to 38 hours at 21 days postimplantation but returned toward the normal (50 hours) with fibrous ingrowth in the sewing ring. Microembolism in lung and kidney, as measured by tissue/blood radioactivity ratio, also was decreased ...

171

Plasma jet ignition device  

Energy Technology Data Exchange (ETDEWEB)

An ignition device of the plasma jet type is disclosed. The device has a cylindrical cavity formed in insulating material with an electrode at one end. The other end of the cylindrical cavity is closed by a metal plate with a small orifice in the center which plate serves as a second electrode. An arc jumping between the first electrode and the orifice plate causes the formation of a highly-ionized plasma in the cavity which is ejected through the orifice into the engine cylinder area to ignite the main fuel mixture. Two improvements are disclosed to enhance the operation of the device and the length of the plasma plume. One improvement is a metal hydride ring which is inserted in the cavity next to the first electrode. During operation, the high temperature in the cavity and the highly excited nature of the plasma breaks down the metal hydride, liberating hydrogen which acts as an additional fuel to help plasma formation. A second improvement consists of a cavity ...

1985-01-15

172

Mode-locked YAG-Nd ring laser with unidirectional stimulated emission  

Energy Technology Data Exchange (ETDEWEB)

The traveling-wave mode in ring lasers is achieved by two methods: by a reversing mirror, and by using an intracavity nonreciprocal device. This paper is devoted to realization of the traveling-wave mode in a mode-locked YAG-Nd ring laser by a method proposed by Tomov et al. This method uses two intracavity Q-switches. In mode-locked operation, pulses are generated that can be considered short compared with the period of modulation T = L/C (where L is the length of the perimeter of the cavity). Analysis shows that if the shift of the switching signals corresponds to the time of travel of a light pulse between Q-switches, the pulse in one direction will pass the Q-switches at instants of zero losses, while losses in the other direction will be maximized for a distance between Q-switches of L/4, and will be zero for a distance L/2. Experimental verification of the proposed method gave unidirectional lasing with an intensity ratio in the two ...

1981-05-01

173

Magnetic Fields in Massive Stars. II. The Buoyant Rise of Magnetic Flux Tubes Through the Radiative Interior  

CERN Document Server

We present results from an investigation of the dynamical behavior of buoyant magnetic flux rings in the radiative interior of a uniformly rotating early-type star. Our physical model describes a thin, axisymmetric, toroidal flux tube that is released from the outer boundary of the convective core, and is acted upon by buoyant, centrifugal, Coriolis, magnetic tension, and aerodynamic drag forces. We find that rings emitted in the equatorial plane can attain a stationary equilibrium state that is stable with respect to small displacements in radius, but is unstable when perturbed in the meridional direction. Rings emitted at other latitudes travel toward the surface along trajectories that largely parallel the rotation axis of the star. Over much of the ascent, the instantaneous rise speed is determined by the rate of heating by the absorption of radiation that diffuses into the tube from the external medium. Since the time ...

2003-01-01

174

Lubrication of an 85-mm ball bearing with RP-1  

Energy Technology Data Exchange (ETDEWEB)

A parametric experimental investigation of an 85 millimeter bore angular contact ball bearing running in RP-1 fuel was performed at speeds of 10,000 to 24,000 rpm. Thrust loads were varied from 4450 to 17,800 Newtons (1000 to 4000 lbs.). Radial loads were varied from 1335 to 13,350 Newtons (300 to 3000 lbs.). RP-1 lubrication for the bearing was provided through a stationary jet ring located adjacent to the test bearing outer ring. Increases in both the thrust and radial loads resulted in increased bearing temperature, while increases in shaft speed resulted in much more dramatic increases in bearing temperature. These trends are typical for ball bearings operating under these types of conditions. Results are given for outer ring temperatures of the test bearing at the various test conditions employed. In addition, the heat energy removed from the bearing by the RP-1 was determined by measuring the increase in temperature ...

1993-01-01

175

Influence of catalytic activity and reaction conditions on the product distribution in coal liquefaction; Sekitan ekikayu no seiseibutsu bunpu ni taisuru shokubai kassei oyobi hanno joken no eikyo  

Energy Technology Data Exchange (ETDEWEB)

The NiMo sulfide supported on Ketjen Black (KB) was more effective and yielded lighter oil products containing light fractions with their boiling point below 300{degree}C during the two stage liquefaction combining low temperature and high temperature hydrogenation the conventional NiMo/alumina catalyst and FeS2 catalyst. Although the NiMo/alumina yielded increased oil products during the two stage liquefaction, the lighter oil fractions did not increase and the heavier fractions increased mainly. This suggests that the hydrogenation of aromatic rings and successive cleavage of the rings are necessary for producing the light oil, which is derived from the sufficient hydrogenation of aromatic rings using catalysts. For the two stage reaction with NiMo/KB catalyst, it was considered that sufficient hydrogen was directly transferred to coal molecules at the first stage of the low temperature reaction, which promoted the ...

1996-10-28

176

Evidence for divided automatic attention  

Scientific Electronic Library Online (English)

Abstract in english A long-standing debate in the literature is whether attention can form two or more independent spatial foci in addition to the well-known unique spatial focus. There is evidence that voluntary visual attention divides in space. The possibility that this also occurs for automatic visual attention was investigated here. Thirty-six female volunteers were tested. In each trial, a prime stimulus was presented in the left or right visual hemifield. This stimulus was characteriz (more) ed by the blinking of a superior, middle or inferior ring, the blinking of all these rings, or the blinking of the superior and inferior rings. A target stimulus to which the volunteer should respond with the same side hand or a target stimulus to which she should not respond was presented 100 ms later in a primed location, a location between two primed locations or a location in the contralateral hemifield. Reaction time to the ...

2008-02-01

177

Evaluation of selected elastomer O-ring pump seals for service at the Wilsonville, Alabama, Advanced Coal Liquefaction Research and Development Facility. [Ethylenepropylenediene monomer compounds  

Energy Technology Data Exchange (ETDEWEB)

Previous laboratory tests of elastomer O-rings in coal liquefaction solvents conducted at L'Garde, Inc., indicated that certain ethylenepropylenediene monomer (EPDM) compounds provided the best performance when a backup ring was used to limit swelling. Before service testing in a pump at the Wilsonville, Alabama, Advanced Coal Liquefaction Research and Development Facility, tests of six selected elastomers in the appropriate Wilsonville-produced solvent were conducted at Oak Ridge National Laboratory (ORNL). The ORNL tests measured the elastomers' changes in cross section, weight, density, and relative flexibility. Although two perfluoroelastomers showed less degradation of most properties during these tests, it was decided to proceed with service testing of two EPDM elastomers because of their much lower cost. 5 refs., 14 figs., 7 tabs.

1986-08-01

178

Evaluation of paramagnetic species in coals with iodine doping technique; Yoso tenkaho wo mochiita sekitanchu no jojiseishu no hyoka  

Energy Technology Data Exchange (ETDEWEB)

Electron paramagnetic resonance (EPR) of coals was considered by using iodine doping technique. Sub-bituminous coal (WA) and bituminous coal (UF) were used to observe EPR spectra using microwaves. With the UF coal, strength of the narrow component of the spectra was found constant regardless of amount of the doped iodine, wherein radicals without interaction with iodine were detected. Strength of the broad component increased with the iodine doping amount, where in deviation of {pi} electrons was detected, which have been generated as a result of interaction between aromatic rings and iodine in the coals. Spin concentration of the WA coal with low coalification degree is constant regardless of the iodine doping amount, and the interaction of the iodine with the aromatic rings was found small. The higher the coalification degree, the more the aromatic ring structure grows, and electron donor capability for the iodine ...

1996-10-28

179

Environmental distribution and behavior of 3H and 14C around Wolsong Nuclear Power Plants.  

Science.gov (United States)

To estimate of the dispersion trend of 3H and 14C discharged from the Wolsung Nuclear Power Plants, the present level of 3H and 14C in environmental samples in the vicinity of the Wolsong site was studied. Tree-ring cellulose analyses were carried out for retrospective evaluation of 3H and 14C in the environment around the Wolsong Nuclear Power Plants. 3H released from the Wolsong Nuclear Power Plants has affected an area up to a 25-km radius from the site, while almost all 14C was deposited within a 2-km radius, reaching to a natural level over 2 km. Organically bound tritium concentrations in tree rings were strongly correlated with the gaseous tritium discharge rate, while delta14C (excess) in tree rings ranged from 204 per thousand to 460 per thousand, which did not significantly vary with year. PMID:10832930

2000-06-01

180

Damping the. pi. -mode instability in the SLC damping rings with a passive cavity  

Energy Technology Data Exchange (ETDEWEB)

Operating the Stanford Linear Collider (SLC) at 120Hz repetition rate requires the presence of two bunches in both the electron and the positron damping ring. The {pi}-mode instability, a coupled bunch instability where the two bunches oscillate with a phase difference of 180{degrees}, had been observed in both rings with low current thresholds of 7{sup *}10{sup 9} particles per bunch. To avoid the instability, the RF system had to be operated in ways which in general reduced the cavity gap voltages and required constant operational attention. For the 1992 running cycle a passive cavity was installed and successfully tested. It is tuned to the frequency of the lower synchrotron oscillation sideband of an odd revolution harmonic. The impedance of the cavity then damps {pi}-mode oscillations very similar to the Robinson damping provided by the main RF cavities which damps O-mode synchrotron oscillations. In this report we describe the motivation ...

1992-07-01

181

Damping the {pi}-mode instability in the SLC damping rings with a passive cavity  

Energy Technology Data Exchange (ETDEWEB)

Operating the Stanford Linear Collider (SLC) at 120Hz repetition rate requires the presence of two bunches in both the electron and the positron damping ring. The {pi}-mode instability, a coupled bunch instability where the two bunches oscillate with a phase difference of 180{degrees}, had been observed in both rings with low current thresholds of 7{sup *}10{sup 9} particles per bunch. To avoid the instability, the RF system had to be operated in ways which in general reduced the cavity gap voltages and required constant operational attention. For the 1992 running cycle a passive cavity was installed and successfully tested. It is tuned to the frequency of the lower synchrotron oscillation sideband of an odd revolution harmonic. The impedance of the cavity then damps {pi}-mode oscillations very similar to the Robinson damping provided by the main RF cavities which damps O-mode synchrotron oscillations. In this report we describe the motivation ...

1992-07-01

182

Chemistry and morphology of coal liquefaction. Quarterly report, January 1, 1986-March 31, 1986. [1,2,3,4 tetrahydroquinoline, 2-propylaniline, quinoline cyclohexylamine and propylbenzene  

Science.gov (United States)

Having recently discovered that polynuclear heteroaromatic nitrogen compounds can be selectively reduced only at the nitrogen containing ring, we have now turned our attention towards the cleavage of the carbon nitrogen bonds in this reduced ring. Highlights for this reporting period are: (1) Studies with the 50% nickel oxide catalyst clearly show that 1,2,3,4-tetrahydroquinoline(THQ) provides approximately 20% more liquid product that does quinoline. Thus a first step selective hydrogenation to 1,2,3,4-THQ would enhance the overall HDN reaction to provide a more substantial conversion to substituted benzene and aniline derivatives. (2) The dramatic effect of the nitrogen atom is to inhibit aromatic ring hydrogenation and, to some extent, carbon-carbon bond hydrogenolysis reactivity. This is shown with proplybenzene as the substrate, where only methane gas is produced in the HDN reaction with the 50% nickel oxide catalyst. ...

1986-03-01

183

Behavior of the positron beam of the Super-ACO storage ring in response to a modification of the RF frequency for free-electron laser experiments  

International Nuclear Information System (INIS)

The macrotemporal structure of the Super-ACO Storage ring free-electron laser (FEL) can be either continuous, pulsed, or chaotic, and can present some rapid fluctuations. The temporal evolution of a storage ring FEL involves both the longitudinal motion of the positron beam (especially the synchrotron oscillations) and the FEL dynamics, as in a coupled system. Studies on the dynamics of the positron beam are performed here, in the goal to have a stable source for FEL applications, and to determine the conditions for a stable Q-switching experiment. The employed method is to study the influence of a controlled change of the radio frequency (RF) (modulation or frequency jump) on the beam. A simple theoretical model taking into account the perturbed RF system is presented to help the understanding of the experimental data. The different methods of measurement are described. Then, the results are given for several experimental conditions and the ...

184

An Investigation of the Relationship Between Tritium in Groundwater and the Dendrochronology of Tritium in Trees at the Savannah River Site. Final report  

Energy Technology Data Exchange (ETDEWEB)

This project was supported through ERDA to demonstrate that the temporal distribution of tritium can be documented by the analysis of bound hydrogen in annual tree-ring samples. The project focuses on two sample locations at the Savannah River Site (SRS), a nuclear material production facility located in Aiken, SC. The SRS provided samples of cross-sections from a single tree that were to be pooled together for analysis. Annual tree-rings were identified in each cross-section sample and separated for the period 1954 to 1993. These annual samples were ground and chemically treated to separate the hollocellulose fraction of the wood, then subsequently combusted and the resulting water counting using low-level liquid scintillation counting equipment. Additionally, the ground annual tree-rings were gamma-counted to determine any temporal variation in radionuclide activity and analyzed with x-ray fluorescence to find any ...

1995-03-21

185

What are $E_{\\infty}$ ring spaces good for?  

CERN Document Server

Infinite loop space theory, both additive and multiplicative, arose largely from two basic motivations. One was to solve calculational questions in geometric topology. The other was to better understand algebraic K-theory. The Adams conjecture is intrinsic to the first motivation, and Quillen's proof of that led directly to his original, calculationally accessible, definition of algebraic K-theory. In turn, the infinite loop understanding of algebraic K-theory feeds back into the calculational questions in geometric topology. For example, use of infinite loop space theory leads to a method for determining the characteristic classes for topological bundles (at odd primes) in terms of the cohomology of finite groups. We explain just a little about how all that works, focusing on the central role played by E infinity ring spaces.

2009-01-01

186

Valued Graphs and the Representation Theory of Lie Algebras  

CERN Document Server

Quivers (directed graphs) and species (a generalization of quivers) and their representations play a key role in many areas of mathematics including combinatorics, geometry, and algebra. Their importance is especially apparent in their applications to the representation theory of associative algebras, Lie algebras, and quantum groups. In this paper, we discuss the most important results in the representation theory of species, such as Dlab and Ringel's extension of Gabriel's theorem, which classifies all species of finite and tame representation type. We also explain the link between species and K-species (where K is a field). Namely, we show that the category of K-species can be viewed as a subcategory of the category of species. Furthermore, we prove two results about the structure of the tensor ring of a species containing no oriented cycles that do not appear in the literature. Specifically, we prove that two such species have isomorphic tensor ...

2011-01-01

187

Synthesis and investigation of #pi#-conjugated azomethine self-assembled multilayers by layer-by-layer growth  

International Nuclear Information System (INIS)

Layer-by-layer formation for #pi#-conjugated azomethine multilayers bonded on substrates was investigated. The multilayers were synthesized using ethanol (EtOH) and dichloromethane (DCM) as reaction solvents. The multilayer characteristics were analyzed using UV-vis absorption spectroscopy, ellipsometric thickness, and atomic force microscopy. The absorption spectra and ellipsometric thicknesses of multilayers formed using EtOH and DCM were compared. The results indicate that EtOH is more suitable than DCM for such layer-by-layer formation. In addition, bandgaps estimated from the absorption edge of multilayers were investigated. The results indicate that the bandgap decreases as the number of benzene rings contained in the molecular chain of the multilayer increases. Also, a multilayer with four benzene rings bonded on a substrate had a bandgap close to that of a polymer with a similar chemical structure.

2010-07-01

188

Recent progress in the storage ring NIJI-IV free electron laser  

International Nuclear Information System (INIS)

A compact storage ring NIJI-IV free electron laser (FEL) is being developed as a tunable light source which covers a wide wavelength range from the VUV to the IR. To shorten the FEL wavelength in the VUV region, the optical cavity mirror was improved and the original loss of Al_2O_3/SiO_2 multilayer mirror around 195nm was decreased 30% compared with that of the previous one. New optical cavity system equipped with two remotely interchangeable mirrors was installed for the UV/VUV FEL to stabilize the laser and also to extend the tuning range. As for construction of the IR FEL, modification of the beam transport system to make space for installation of the optical cavity was completed. (author)

2006-08-01

189

Performance of ceramics in ring/cylinder applications  

Energy Technology Data Exchange (ETDEWEB)

In support of the efforts to apply ceramics to advanced heat engines, a study is being performed of the performance of ceramics at the ring/cylinder interface of advanced (low heat rejection) engines. The objective of the study, managed by the Oak Ridge National Laboratory, is to understand the basic mechanisms controlling the wear of ceramics and thereby identify means for applying ceramics effectively. Attempts to operate three different zirconias, silicon carbide, silicon nitride, and plasma-sprayed ceramic coatings without lubrication have not been successful because of excessive friction and high wear rates. Silicon carbide and silicon nitride perform well at ambient temperatures with fully formulated mineral oil lubrication, but are limited to temperatures of 500F because of the lack of suitable liquid lubricants for higher temperatures.

1987-01-01

190

Mineralization and volatilization of ring labelled "1"4C-2,4-D in three different soils  

International Nuclear Information System (INIS)

Mineralization and volatilization of ring labelled "1"4C-2,4-dichlorophenoxyacetic acid in soil was studied over a period of six weeks under laboratory conditions at 25 deg. C in three different soils collected from three sites, Delhi, Jaipur and Ludhiana. A very slow rate of both mineralization and volatilization was observed in all the three soils. The observed mineralization, was highest for the Delhi soil, 0.93%, followed by the Ludhiana soil, 0.73% and the Jaipur soil 0.14% in 42 days. The extent of volatilization was 0.46% for the Jaipur soil, 0.37% for the Ludhiana soil and 0.32% for the Delhi soil. (author)

2001-11-01

191

Ligand Tuning in Asymmetric Hydrovinylation of 1,3-Dienes. A Stereoselective Route to either Steroid-C20 (S) or -C20 (R) Derivatives  

Science.gov (United States)

1,3-Dienes derived from steroidal D-ring C17-ketones undergo Ni(II)-catalyzed hydrovinylation to give 1,2- or 1,4-addition of ethylene. Using finely tuned phosphoramidite ligands it is possible to synthesize either the C20 (R)- or the C20 (S)-derivatives without mutual contamination. The proportion of the 1,4-adduct, which is also formed stereoselectively, can be minimized by optimizing the reaction conditions. Since the two alkenes in the resultant dienes have differing steric demands for many potential reactions, and are ideally juxtaposed for further D-ring functionalization, these intermediates could be useful for the preparation of biologically important compounds such as vitamin D analogs and various antitumor steroidal glycosides.

2008-06-21

192

Gamma rays produced by inverse Compton scattering in the super-ACO storage ring free electron laser  

International Nuclear Information System (INIS)

The inverse Compton scattering between positron bunches and the Free Electron Laser (FEL) of the SuperAco storage ring generates a collimated and tunable gamma-ray beam. The use of the FEL instead of a conventional laser, automatically provides the transverse alignment and synchronisation of the electron and optical beams. The Super-ACO FEL is operated in the 300-430 nm range at 800 MeV with a high repetition rate (8 MHz) and an average transmitted power of 300 mW at 350 nm. High energy gamma rays of 35 MeV are produced with a rate of 1.5 10 7 photons/second and good monocromaticity (about 10%). Applications of the SuperAco FEL installation for diamond irradiation and biological studies are envisaged. (author)

2000-06-05

193

Full-scale model of cooling and heating system for JT-60 vacuum vessel  

Science.gov (United States)

A full-scale model of a rigid sectorial ring and a set of bellows which was covered with a temperature control layer and a coolant supply equipment was constructed to verify the adequacy of the heating and cooling system designed for JT-60. To cool and heat it effectively and to decrease the temperature differences among the various parts in the vacuum vessel, heater units and cooling pipes were located on the surface of the ring. The temperature control layer is to heat the vessel to 500/degree/sub //C within 70 hours and to maintain it at the temperature for 48 hours for simulating the state of bakeout. Subsequently the vessel is cooled down within about the same time as in heating. Prior to the series of tests, numerical analyses were performed to predict the cooling and heating efficiencies on the model and to examine the method of the temperature regulation.

1981-01-01

194

Energy saver A-sector power test results  

Energy Technology Data Exchange (ETDEWEB)

The superconducting magnets and associated cryogenic components in A-sector represent the initial phase of installation of the Fermilab superconducting accelerator, designed to accelerate proton beams to energies of 1 TeV. Installation of the magnets, comprising one-eighth of the ring, was completed in December, 1981. Cooldown and power tests took place in the first half of 1982, concurrent with main ring use for 400 GeV high energy physics. The tests described in this paper involved 151 cryogenic components in the tunnel: 94 dipoles, 24 quadrupoles, 25 spool pieces, 3 feed cans, 4 turn-around boxes and 1 bypass. Refrigeration was supplied by three satellite refrigerators, the Central Helium Liquefier, and two compressor buildings. The magnets were powered by a single power supply.

1982-09-15

195

Effects of carbon fiber surface treatment on the tribological properties of 2D woven carbon fabric/polyimide composites  

British Library Electronic Table of Contents (United Kingdom)

Polyacrylonitrile (PAN)-based carbon fabric (CF) was modified with strong HNO3 oxidation and then introduced into polyimide (PI) composites. The friction and wear properties of the carbon fabric reinforced polyimide composites (CFRP), sliding against GCr15 stainless steel rings, were investigated on an M-2000 model ring-on-block test rig under dry sliding. Experimental results revealed that the carbon fiber surface treatment largely reduced the friction and wear of the CFRP. Compared with the untreated ones, the surface-modified CF can enhance the tribological properties of CFRP efficiently due to the improved adhesion between the CF and the PI matrix. Scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) study of the carbon fiber surface showed that the fiber surfa...

2009-01-01

196

Effect of carbon fibers surface treatment on tribological performance of polyurethane (PU) composite coating  

British Library Electronic Table of Contents (United Kingdom)

The carbon fibers (CF) were pre-treated in two different ways: no pre-treatment, and activation in HNO3 plus application of toluene-2,4-diisocyanate (TDI). Carbon fibers have been introduced into polyurethane (PU) composite coatings. The tribological behaviors of the polyurethane composite coating filled with CF or TDI-modified CF (TDI-CF) were studied using a ring-on-block wear tester under dry sliding, and the worn surfaces of the filled PU coatings and transfer films formed on the surface of the counterpart ring sliding against the PU coating were investigated by SEM and optical microscope (OM), respectively. Owing to the effective improvement of the interfacial adhesion between the CF and polyurethane matrix, compared with the cases of untreated CF, the employment of low content TDI-CF...

2008-01-01

197

Effect of carbon fiber surface treatments on the flexural strength and tribological properties of short carbon fiber/polyimide composites  

British Library Electronic Table of Contents (United Kingdom)

Pitch-based short carbon fibers (CFs) were treated by air oxidation and cryogenic nitrogen, respectively. Thereafter the treated and untreated CFs were incorporated into polyimide (PI) matrix to form composites. The CFs before and after treatment were examined by XPS and SEM.The flexural strength of the specimen was determined in a three-point test machine and the tribological properties of PI composites sliding against GCr15 steel rings were evaluated on an M-2000 model ring-on-block test rig. The results show that the surface of the treated CFs became rougher. Lots of active groups formed on the CF surface after air oxidation.The treatment can effectively improve the mechanical and tribological properties in their PI composites due to the enhanced fiber-matrix interfacial bonding. Copyri...

2008-01-01

198

Development of ball bearings with solid film for high-vacuum, high-temperature, high-speed application  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the experimental results of long-life solid lubricated ball bearings tested under high-vacuum of 10 exp -4 Pa, high-temperature of 300 C, and high-speed (9000 rpm) conditions. For full ball-type bearings, the thin soft metals, either Ag or Pb, which were coated on the races and balls, appeared to have good torque properties. However, the durability of such bearings was less than 300 hours. The transfer films from the lamellar solid MoS2 and metal composite retainers improved the torque and wear properties. For ceramic, i.e., silicon nitride, balls used with steel rings, wear occurred on the inner rings. All ceramic bearings with composite retainers showed improved torque and wear properties. 18 refs.

1993-04-01

199

Damping Ring to Interaction Point Beam Transport Issues  

CERN Document Server

One of the major challenges facing the proposed high-energy linear e^+e^ colliders is the preservation of the extremely small vertical emittance from the damping rings to the interaction point (IP). This emittance must be transported through bunch compression sections, the main linac and finally through the beam delivery system to the IP. Historically, the beam dynamics issues of each subsystem have been studied quasi-independently, with the beam conditions and tolerances being specified at the boundaries. As part of the recent International Linear Collider Technical Review Committee, new simulation tools have been developed to simulate the beam transport through the integrated system, including static and dynamic errors, stabilization systems, and tuning algorithms.

2003-01-01

200

Consistency conditions in the chiral ring of super Yang-Mills theories  

CERN Document Server

Starting from the generalized Konishi anomaly equations at the non-perturbative level, we demonstrate that the algebraic consistency of the quantum chiral ring of the N=1 super Yang-Mills theory with gauge group U(N), one adjoint chiral superfield X and N_f<=2N flavours of quarks implies that the periods of the meromorphic one-form Tr dz/(z-X) must be quantized. This shows in particular that identities in the open string description of the theory, that follow from the fact that gauge invariant observables are expressed in terms of gauge variant building blocks, are mapped onto non-trivial dynamical equations in the closed string description.

2007-01-01

201

Chiral Rings, Mirror Symmetry and the Fate of Localized Tachyons  

Energy Technology Data Exchange (ETDEWEB)

We study the localized tachyon condensation of non-supersymmetric orbifold backgrounds in their mirror Landau-Ginzburg picture. We first show that the R-charges of chiral primaries increase under the process of condensing the tachyon in the same chiral ring. Then, utilizing the existence of four copies of (2,2) worldsheet supersymmetry, we show that the minimal tachyon mass in twisted sectors increases in CFT and type 0 string and it plays the role of the c-function of the twisted sectors. We also study the GSO projection in detail and show that type II decays to only to type II while type 0 can mix with type 0 and II under the RG-flow.

2003-03-20

202

A new model for precision control of the radius in in-plane roll-bending of strip considering rolls and stand deflections  

British Library Electronic Table of Contents (United Kingdom)

The rolls and stand deflections induced by rolling force lead to a significant decrease in the radius prediction accuracy of the ring product in the in-plane roll-bending of strip. To precisely predict the deflections and control the radius, a new analytical model is developed. Numerical implementation is presented to solve the theoretical rolling force, the deflections as well as the inherent force-deflection relationship considering the interactions of the strip workpiece, the rolls and the stand. A series of profile measurements of the formed ring parts are made to assess the accuracy of the predicted deflections. Different control approaches are used in the experiments to validate the radius control model. The experimental results show that the model is reliable to control the radii wi...

2011-01-01

203

Surge-line thermal stratification: Displacements and fatigue damage computations  

Energy Technology Data Exchange (ETDEWEB)

Slow, unexpected displacements have been experienced in most pressurized water reactor (PWR) surge lines. Sometimes, these displacement lead to gap closure at the pipe whip restraints. These movements occur because of thermal stratification. This movement has the potential to increase stresses to valves, which may exceed the material yield stress. To understand this phenomenon, Framatome, Commissariat a l'Energie Atomique, and Electricite de France have undertaken large programs for the study of (1) thermal-hydraulic tests with a half-scale Plexiglas surge line, (2) thermal-hydraulic computations of permanent states and transients with a two-dimensional model, and (3) mechanical analysis of displacements and computation of fatigue damage due to stratification. This paper deals with the last subject. Avoiding stratification in piping by process modifications is difficult because of the high flow rate needed. Alternative solutions for coping with ...

1989-01-01

204

Phase chemistry and radionuclide retention of high level radioactive waste tank sludges  

Energy Technology Data Exchange (ETDEWEB)

The US Department of Energy (DOE) has millions of gallons of high level nuclear waste stored in underground tanks at Hanford, Washington and Savannah River, South Carolina. These tanks will eventually be emptied and decommissioned. This will leave a residue of sludge adhering to the interior tank surfaces that may contaminate groundwaters with radionuclides and RCRA metals. Experimentation on such sludges is both dangerous and prohibitively expensive so there is a great advantage to developing artificial sludges. The US DOE Environmental Management Science Program (EMSP) has funded a program to investigate the feasibility of developing such materials. The following text reports on the success of this program, and suggests that much of the radioisotope inventory left in a tank will not move out into the surrounding environment. Ultimately, such studies may play a significant role in developing safe and cost effective tank closure strategies.

2000-05-19

205

Omental pedicle flap used to treat a bronchopleural fistula after diaphragma--pericardio-pleuropneumonectomy.  

Science.gov (United States)

In a 47-year-old male patient a bronchopleural fistula was apparent 22 days after extended right-sided diaphragma-pericardio-pleuro-pneumonectomy for pleuramesothelioma. The thoracic cavity was infected. Rethoracotomy was performed and the fistula was closed using an omental pedicle flap. The bronchial stump became tight and the cavity fluid became sterile. No abdominal complications were seen. The patient died 8 months later from malignant pericardial infiltration. The ability of greater omentum to revascularize ischemic tissue, to absorb fluid and to resist local infection is proved and used in several subspecialities of surgery. Nevertheless the use of the greater omentum in the management of bronchopleural fistula has been rarely published. The reported case shows that the closure of a large bronchopleural fistula is possible by using the attributes of the omental tissue. PMID:2264043

1990-10-01

206

Effects of size and spacing of uniformly distributed pearlite particles on fatigue crack growth behavior of ferrite pearlite steels  

British Library Electronic Table of Contents (United Kingdom)

Fatigue crack growth tests of three ferrite-pearlite steels with different size and spacing of pearlite particles, which were uniformly distributed in the ferrite matrix, were carried out to investigate the effect of microstructure on fatigue crack growth behavior in the Paris regime. The fatigue crack growth rates for the three materials did not coincide with each other, even when the crack growth curves were arranged by the effective stress intensity factor range. From in situ observations, crack tip stress shielding phenomena, such as interlocking and branching, were found on the crack wake, which enhanced fatigue crack growth resistance. A small size and spacing of pearlite particle seemed to induce small but frequent crack deflections, which resulted in crack closure phenomena. On the...

2010-01-01

207

Economic-impact analysis of effluent limitations and standards for the battery-manufacturing industry  

Energy Technology Data Exchange (ETDEWEB)

The report identifies and analyzes the economic impacts of water pollution control regulations on the battery manufacturing industry. These regulations include effluent limitations and standards based on BPT (best practical control technology currently available), BAT (best available technology economically achievable), PSES (pretreatment standards existing sources), NSPS (new source performance standards), and PSNS (pretreatment standards new sources), that have been promulgated under authority of Sections 301, 304, 306, 307, 308, and 501 of the Federal Water Pollution Control Act, as Amended (the Clean Water Act). The primary economic impact variables of interest include price changes, plant closures, substitution effects, changes in employment, shifts in the balance of foreign trade, changes in industry profitability, structure, and competition, and impacts on small business.

1984-01-01

208

Economic impact analysis of proposed effluent limitations and standards for the gold placer mining industry  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the study is to analyze the economic impacts that are likely to result from promulgation of the proposed best practicable control technology (BPT), best available technology economically achievable (BAT) and Best Conventional Technology (BCT) effluent limitations and standards on placer mining in the United States. The results of the economic impact analysis will help establish pollution control regulations that are economically achievable. The analysis examines how each of four alternative pollution control technologies affects the financial viability of placer mines in the United States. The impacts examined include reduced profitability, production cutbacks, mine closures, and employment and earning losses, as well as impacts to the local economies.

1985-08-01

209

Decay of very neutron-rich Mn nuclides and vanishing of the N=40 subshell closure in {sup 66}Fe  

Science.gov (United States)

The use of chemically selective laser ionization combined with beta-delayed neutron counting at ISOLDE has permitted identification and half-life measurements for {sup 61}Mn up through {sup 69}Mn. The 14(4)-ms half life for {sup 69}Mn is one of the shortest determined for any nuclide beyond the sd shell. Gamma-ray singles and coincidence spectra have been determined for the decays of {sup 64,66}Mn to levels of {sup 64,66}Fe, revealing strong deformation and vanishing of the N=40 subshell in the Fe isotopes. {copyright} {ital 1998 American Institute of Physics.}

1998-12-01

210

Decay of very neutron-rich Mn nuclides and vanishing of the N=40 subshell closure in "6"6Fe  

International Nuclear Information System (INIS)

The use of chemically selective laser ionization combined with beta-delayed neutron counting at ISOLDE has permitted identification and half-life measurements for "6"1Mn up through "6"9Mn. The 14(4)-ms half life for "6"9Mn is one of the shortest determined for any nuclide beyond the sd shell. Gamma-ray singles and coincidence spectra have been determined for the decays of "6"4","6"6Mn to levels of "6"4","6"6Fe, revealing strong deformation and vanishing of the N=40 subshell in the Fe isotopes.

1998-12-21

211

Cosmic-ray antiprotons, positrons, and gamma rays from halo dark matter annihilation  

Energy Technology Data Exchange (ETDEWEB)

The subject of cosmic ray antiproton production is reexamined by considering other choices for the nature of the Majorana fermion chi other than the photino considered in a previous article. The calculations are extended to include cosmic-ray positrons and cosmic gamma rays as annihilation products. Taking chi to be a generic higgsino or simply a heavy Majorana neutrino with standard couplings to the Z-zero boson allows the previous interpretation of the cosmic antiproton data to be maintained. In this case also, the annihilation cross section can be calculated independently of unknown particle physics parameters. Whereas the relic density of photinos with the choice of parameters in the previous paper turned out to be only a few percent of the closure density, the corresponding value for Omega in the generic higgsino or Majorana case is about 0.2, in excellent agreement with the value associated with galaxies and one which is sufficient to give the halo mass. 52 ...

1988-02-01

212

Circular map for supercavitating flow in a multiply connected domain  

British Library Electronic Table of Contents (United Kingdom)

A nonlinear free boundary-value problem of supercavitating flow past n + 1 hydrofoils is analyzed. To describe the cavities' closure mechanism, the Tulin-Terentev single-spiral-vortex model is employed. The flow domain is considered as the image of an (n + 1)-connected circular domain. The conformal map is constructed in terms of the solutions to two Riemann-Hilbert problems of the theory of symmetric automorphic functions. One of the problems is homogeneous and its coefficients are continuous functions while the second problem is inhomogeneous and has discontinuous coefficients. The exact solutions to the problems are found by using quasiautomorphic and quasimultiplicative analogs of the Cauchy kernel. The case of a single plate is considered in detail and the numerical results are report...

2009-01-01

213

CLOSURE OF THE FAST FLUX TEST FACILITY (FFTF) HISTORY & STATUS & FUTURE PLANS  

Energy Technology Data Exchange (ETDEWEB)

In 1993, the US Department of Energy (DOE) decided to shut down the Fast Flux Test Facility (FFTF) due to lack of national missions that justified the annual operating budget of approximately $88M/year. The initial vision was to ''deactive'' the facility to an industrially and radiologically safe condition to allow long-term, minimal surveillance storage until approximately 2045. This approach would minimize near term cash flow and allow the radioactive decay of activated components. The final decontamination and decommissioning (D and D) would then be performed using then-current methodology in a safe and efficient manner. the philosophy has now changed to close coupling the initial deactivation with final D and D. This paper presents the status of the facility and focuses on the future challenge of sodium removal.

2006-02-24

214

A numerical study on the long term thermo-poroelastic effects of cold water injection into naturally fractured geothermal reservoirs  

British Library Electronic Table of Contents (United Kingdom)

The residing fracture system and the prevailing in situ stresses have a significant impact on fluid flow and heat transfer in crystalline rocks. The long term response of fracture systems to changes in effective stresses, in particular the long term geo-mechanical effects of thermal stresses on reservoir characteristics is of particular interest to the geothermal industry.In this paper, a geothermal reservoir model is presented, in which a thermo-poroelastic finite element module is coupled to a fracture geomechanical module. This describes fracture closure as a function of effective stress and the changes in parameters, such as effective permeability, porosity and discrete fracture apertures. The novelty of this approach lies in its dynamic treatment of the characteristic properties of in...

2011-01-01

215

Top physics at the Tevatron Collider  

Energy Technology Data Exchange (ETDEWEB)

The top quark has been discovered in 1995 at the CDF and DO experiments located in the Tevatron ring at the Fermilab laboratory. After more than a decade the Tevatron collider, with its center-of-mass energy collisions of 1.96 TeV, is still the only machine capable of producing such exceptionally heavy particle. Here I present a selection of the most recent CDF and DO measurements performed analyzing {approx} 1 fb{sup -1} of integrated luminosity.

2007-10-01

216

The metabolism of L-tryptophan by isolated rat liver cells. Effect of albumin binding and amino acid competition on oxidatin of tryptophan by tryptophan 2,3-dioxygenase.  

UK PubMed Central (United Kingdom)

1. Novel methods, using L-[ring-2-14C]tryptophan, are described for the measurement of tryptophan 2,3-dioxygenase activity and tryptophan accumulation in isolated rat liver cells. 2. The effects of...Full Text Available

1980-03-15

217

The influence of the nonhomogeneous temperature field on the optimal winding prestress of the compound pressure vessel  

Energy Technology Data Exchange (ETDEWEB)

The completed ribbon-winding theory, including temperature loading of the high-pressure compound vessel, was proposed. The influence of the bending stress in the wound ribbon is taken into account. Internal core of the compound vessel consists of matrix and ring, made of different materials. The relations were derived in analytical form, describing the radial distribution of necessary tangential prestressing.

1996-11-01

218

The effects of diphenyleneiodonium on mitochondrial reactions. Relation of binding of diphenylene[125I]iodonium to mitochondria to the extent of inhibition of oxygen uptake.  

UK PubMed Central (United Kingdom)

1. Several ring-substituted derivatives of diphenyleneiodonium catalyse the exchange of Cl- and OH- ions across the inner membrane of rat liver mitochondria. They also inhibit state 3 and state 3u oxidations...Full Text Available

1976-08-15

219

Super-ACO free-electron laser (FEL) operation with a reduced momentum compaction factor  

International Nuclear Information System (INIS)

A new optics providing an emittance close to the minimum theoretical value has been proposed for the Super-ACO storage ring with a reduced value of the momentum compaction factor and non-zero dispersive function in the Free-Electron Laser (FEL) section. It has been adapted to the FEL operation mode, with two RF cavities at 100 and 500 MHz. The obtained results concerning this new optics and the FEL oscillation are presented.

2002-05-01

220

Rising Total Hadron-Hadron Cross Sections  

CERN Document Server

A historical summary is made on the measurements concerning the rising total hadron-hadron cross sections at high energies. The first part of this paper concerns the total cross section measurements performed at the Brookhaven, Serpukhov and Fermilab fixed target accelerators; then the measurements at the CERN Intersecting Storage Rings (ISR), and at the CERN and at the Tevatron Fermilab proton-antiproton colliders; finally the cosmic ray measurements at even higher energies. A short discussion on Conclusions and Perspectives follows.

2007-01-01

221

Real time closed orbit correction system  

Energy Technology Data Exchange (ETDEWEB)

We describe a global closed orbit feedback experiment, based upon a real time harmonic analysis of both the orbit movement and the correction magnetic fields. The feedback forces the coefficients of a few harmonics near the betatron tune to vanish, and significantly improves the global orbit stability. We present the results of the experiment in the UV ring using 4 detectors and 4 trims, in which maximum observed displacement was reduced by a factor of between 3 and 4. 4 refs., 3 figs.

1989-01-01

222

Reaction of ethyl azidoformate with acenaphthylene: isolation and structure of an acenaphthylene-pyridinium-2,6 betaine adduct  

International Nuclear Information System (INIS)

Ethyl azidoformate reacts, on thermolysis with acenaphthylene, to give a 1:2 adduct involving sequential aziridine formation, ring-opening to a 1,3-dipolar pyridinium-2,6-betaine, and trapping of the dipole with acenaphthylene. The structure of the adduct was confirmed by X-ray crystallography.

223

Raman Under Nitrogen. The High-Resolution Raman Spectroscopy of Crystalline Uranocene, Thorocene, and Ferrocene  

Science.gov (United States)

The utility of recording Raman spectroscopy under liquid nitrogen, a technique we call Raman Under Nitrogen (RUN), is demonstrated for ferrocene, uranocene and thorocene. Using RUN, low temperature (liquid nitrogen cooled) Raman spectra for these compounds exhibit higher resolution than previous studies and new vibrational features are reported. The first Raman spectra of crystalline uranocene at 77 K are reported using excitation from argon (5145 ) and krypton (6764 ) ion lasers. The spectra obtained showed bands corresponding to vibrational transitions at 212, 236, 259, 379, 753, 897, 1500, and 3042 cm-1 , assigned to ring-metal-ring stretching, ring-metal tilting, out-of-plane CCC bending, in-plane CCC bending, ring-breathing, C-H bending, CC stretching and CH stretching, respectively. The assigned vibrational bands are compared to those of uranocene in THF and thorocene. All vibrational frequencies of the ligands, ...

2004-02-08

224

Raman Under Nitrogen. The High-Resolution Raman Spectroscopy of Crystalline Uranocene, Thorocene, and Ferrocene  

International Nuclear Information System (INIS)

The utility of recording Raman spectroscopy under liquid nitrogen, a technique we call Raman Under Nitrogen (RUN), is demonstrated for ferrocene, uranocene and thorocene. Using RUN, low temperature (liquid nitrogen cooled) Raman spectra for these compounds exhibit higher resolution than previous studies and new vibrational features are reported. The first Raman spectra of crystalline uranocene at 77 K are reported using excitation from argon (5145 ) and krypton (6764 ) ion lasers. The spectra obtained showed bands corresponding to vibrational transitions at 212, 236, 259, 379, 753, 897, 1500, and 3042 cm-1 , assigned to ring-metal-ring stretching, ring-metal tilting, out-of-plane CCC bending, in-plane CCC bending, ring-breathing, C-H bending, CC stretching and CH stretching, respectively. The assigned vibrational bands are compared to those of uranocene in THF and thorocene. All vibrational frequencies of the ligands, ...

2004-02-08

225

Preparation and Properties of Antibodies against Indoleacetic Acid (IAA)-C5-BSA, a Novel Ring-Coupled IAA Antigen, as Compared to Two Other Types of IAA-Specific Antibodies 1  

UK PubMed Central (United Kingdom)

Two types of indoleacetic acid (IAA) antigens have been described in the literature which show marked differences with respect to antibody specificity. In this communication an alternative antigen design...Full Text Available

1989-04-01

226

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

227

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

228

Photon storage cavities  

Energy Technology Data Exchange (ETDEWEB)

A general analysis is presented of a photon storage cavity, coupled to free-electron laser (FEL) cavity. It is shown that if the coupling between the FEL cavity and the storage cavity is unidirectional (for example, a ring resonator storage cavity) then storage is possible, but that if the coupling is bi-directional then storage is not possible. Parameters are presented for an infra-red FEL storage cavity giving an order of magnitude increase in the instantaneous photon power within the storage cavity. 4 refs., 3 figs.

1991-08-01

229

P and e identification capabilities CAPRICE  

Energy Technology Data Exchange (ETDEWEB)

The cosmic antiparticle ring imaging Cherenkov experiment (CAPRICE) flew on a stratospheric balloon 8-9 August 1994 over northern Canada and collected data for more than 21 hours with less than 5 g/cm{sup 2} of residual atmosphere. The instrument includes a solid radiator RICH detector and an electromagnetic calorimeter for particle identification in the magnetic spectrometer. Preliminary antiproton and positron identification capabilities are presented.

1995-09-01

230

News from Smithers Rapra  

Wastenet

...of Mixing Sections 9 Interacting Rotor/Stator Mixers 10 Floating Ring Mixing Devices 11 Static (or Motionless) Mixers 12 Incorporation of Liquid Additives and Dispersions by Direct Addition 13 Dispersive Mixing of Fillers and Pigments 14 Dispersive Mixing Applied to Polymer Blending 15 Compounding with Single Screw Extruders Appendix - Preparation of Microtome Sections for Assessment of Dispersive In order to get a feel for this book, you can view Chapter 1 now, simply follow the link ...

231

Nanophotonic components utilizing channel plasmon polaritons  

Science.gov (United States)

Channel plasmon polaritons (CPPs) propagating along the bottom of subwavelength grooves cut into a metal surface were recently shown to exhibit strong confinement combined with low propagation loss, a feature that makes this guiding configuration very promising for the realisation of ultra-compact photonic components. Here, the results of our investigations of CPP guiding by V-grooves cut into gold are presented, demonstrating efficient large-angle bending and splitting of radiation as well as waveguide-ring resonators and Bragg grating filters.

2008-08-01

232

Multi-mirror system, 2. Application of inverse Compton Scattering for lithography X-ray sources  

Energy Technology Data Exchange (ETDEWEB)

A brilliant X ray source is proposed for lithography instruments with use of a multi-mirror system. The inverse Compton scattering between the stored electron beam in the storage ring and the stored photon beam in the multi-mirror system, is applied for the X-ray generation. (author)

2000-07-01

233

Metabolism of 4-chloro-2-methylphenoxyacetate by a soil pseudomonad. Ring-fission, lactonizing and delactonizing enzymes  

UK PubMed Central (United Kingdom)

1. A cell-free system, prepared from Pseudomonas N.C.I.B. 9340 grown on 4-chloro-2-methylphenoxyacetate (MCPA) was shown to catalyse the reaction sequence: 5-chloro-3-methylcatechol...Full Text Available

1971-05-01

234

Measurements of Cabibbo Suppressed Hadronic Decay Fractions of Charmed D0 and D+ Mesons  

CERN Document Server

Using data collected with the BESII detector at $e^{+}e^{-}$ storage ring Beijing Electron Positron Collider, the measurements of relative branching fractions for seven Cabibbo suppressed hadronic weak decays $D^0 \\to K^- K^+$, $\\pi^+ \\pi^-$, $K^- K^+ \\pi^+ \\pi^-$ and $\\pi^+ \\pi^+ \\pi^- \\pi^-$, $D^+ \\to \\bar{K^0} K^+$, $K^- K^+ \\pi^+$ and $\\pi^- \\pi^+ \\pi^+$ are presented.

2005-01-01

235

Laser-induced fluorescence measurement of sup(6,7)lithium isotope shift  

Energy Technology Data Exchange (ETDEWEB)

Values of frequency splittings in the lithium isotopes have been determined with the aid of laser-induced fluorescene in a supersonic beam, perpendicularly irradiated by a CW ring dye laser. The residual 2s-2p isotope shift has been found to bw 4721.8 +- 2.0 MHz, leading to a specific mass shift for the 2p level of -3610.8 +- 5 MHz.

1986-07-01

236

Incidental Findings in Genetics Research Using Archived DNA  

UK PubMed Central (United Kingdom)

You were a patient at Hospital A several years ago when you were suffering from disease X, which has long since resolved. You have just arrived home from a long day's work when the phone rings....Full Text Available

2008-01-01

237

Hyperbolicity of Semigroup Algebras II  

CERN Document Server

In 1996 Jespers and Wang classified finite semigroups whose integral semigroup ring has finitely many units. In a recent paper, Iwaki-Juriaans-Souza Filho continued this line of research by partially classifying the finite semigroups whose rational semigroup algebra %over a field of characteristic zero, contains a ${\\mathbb{Z}}$-order with hyperbolic unit group. In this paper we complete this classification by handling the case in which the semigroup is semi-simple.

2008-01-01

238

HELIUM FLOW INDUCED ORBIT JITTER AT RHIC.  

Energy Technology Data Exchange (ETDEWEB)

Horizontal beam orbit jitter at frequencies around 10 Hz has been observed in RHIC for several years. The distinct frequencies of this jitter have been found at superconducting low-beta quadrupole triplets around the ring, where they coincide with mechanical modes of the cold masses. Recently, we have identified liquid helium flow as the driving force of these oscillations.

2005-05-16

239

Forschungszentrum Juelich, Institut fuer Kernphysik. Annual report 1994  

Energy Technology Data Exchange (ETDEWEB)

This volume contains the annual report describing the work carried out at COSY (Cooled Synchrotron Storage Ring at KFA Juelich). The results in both machine and physics program are presented on the main topics experimental nuclear physics, theoretical nuclear physics, accelerator developments and technical developments. (MSA)

1995-02-01

240

Domain structure of ferrite-garnet crystalline plates (111) with uniaxial anisotropy  

Energy Technology Data Exchange (ETDEWEB)

Magnetic field, thickness and magnetic forming effect on general mode and quantitative parameters of the domain structure (DS) of ferrite-garnet (EuEr)/sub 3/(FeGa)/sub 5/O/sub 12/ monocrystalline plates (111) is investigated. Field interval of circle (cone) and ring domain stability is determined. It is shown that DS of ferrite-garnet crystals with uniaxial an6sotropy has some peculiarities, that can be explained by cubic anisotropy effect.

1982-03-01

241

Disk's Spiral Arms Point to Possible Planets  

National Aeronautics and Space Administration (NASA)

Simulations of young stellar systems suggest that planets embedded in a circumstellar disk can produce many distinctive structures, including rings, gaps and spiral arms. This video compares computer simulations of hypothetical systems to an image of system SAO 206462 taken by the Subaru Telescope and its HiCIAO instrument. n nCredit: NASA Goddard Space Flight Center/NCSA

2011-10-18

242

Digital signal processing for beam position feedback  

Energy Technology Data Exchange (ETDEWEB)

Stabilization of the particle beam position with respect to the focusing optics in the third generation synchrotron light sources is crucial to achieving low emittance and high brightness. For this purpose, global and local beam orbit correction feedbacks will be implemented in the APS storage ring. In this article, the authors discuss application of digital signal processing to particle/photon beam position feedback using the PID (proportional, integral, and derivative) control algorithm.

1992-04-01

243

Details about emission sources for IMF's in heavy ion collisions  

International Nuclear Information System (INIS)

A large IMF- and event characterizing multidetector system (CHICSI) is under development for storage ring experiments. In ''test'' experiments with telescopes of CHICSI type the IMF production has been measured for "1"4N induced reactions at 14A and 32A MeV. Detailed information about the emission sources, particularly from the IMF yield in reactions with isotope separated targets and from isobaric yield ratios in the sub-Coulomb region is discussed. (orig.).

1994-01-17

244

Container for the long-term storage of radioactive substances with a lid tightening device  

International Nuclear Information System (INIS)

The invention concerns a container for the long term storage of irradiated nuclear reactor fuel elements, which consists mainly of a basic body, at least one lid and an outside ring shaped lid tightening device, which acts on the basic body and the lid and holds the contact surface of the lid tight against the contact surface of the basic body, where the basic body, lid and the lid tightening device consist of corrosion-proof materials. (orig./HP).

1983-09-24

245

Coal liquefaction catalzsed by iron ores. Catalytic activities of laterite ores  

Energy Technology Data Exchange (ETDEWEB)

The catalytic activities of various iron ores were investigated in the search for a high-activity catalyst for direct coal liquefaction. Laterite ores were shown to have a high catalytic activity in this process. Comparison of the ore with red mud in hydrocracking of 1-methylnaphthalene showed that the ore had higher activity in the hydrogenation of aromatic rings and in hydrocracking of alkylaromatics.

1984-10-01

246

Calcium fluoride window mounting  

International Nuclear Information System (INIS)

A technique has been developed for joining a large calcium fluoride crystal to a stainless-steel flange by means of a silver transition ring. The process involves both vacuum brazing using a copper-silver alloy and air brazing using silver chloride. This paper describes the procedure used in fabricating a high-vacuum leak-tight calcium fluoride window assembly.

247

An improved method for hyaluronic acid radioiodination  

Energy Technology Data Exchange (ETDEWEB)

A simple procedure is described for preparing {sup 125}I-labelling hyluronan of high molecular weight. The reducing terminal group of hyaluronic acid was derivatized with tyramine through the formation of a Schiff base which was subsequently reduced with sodium cyanoborohydride. By radioiodination of the aromatic ring, {sup 125}I-labelled hyaluronic acid was obtained in high yield (40%) and high specific activity, 555 GBq/mmol (15 Ci/mmol). (Author).

1995-09-01

248

A new species of Demidospermus (Platyhelminthes, Monogenea, Ancyrocephalidae) from the catfish Parapimelodus valenciennis in Samboromb?n Bay, Argentina  

British Library Electronic Table of Contents (United Kingdom)

Demidospermus annulus sp. nov. (Platyhelminthes, Monogenea, Ancyrocephalidae) is described from the gills of the catfish Parapimelodus valenciennis L?tken collected in Samboromb?n Bay, Argentina. The new species differs from all congeneric species mainly by the structure of the accessory piece of the male copulatory organ, the sclerotized ring-shaped vaginal aperture and the dorsal bar articulation.

2011-01-01

249

Surface and subsurface analysis of Sheep Mountain anticline, Wyoming  

Energy Technology Data Exchange (ETDEWEB)

The Sheep Mountain area, in the southwest Wind River Basin, is the up plunge closure of the Derby Dome-Winkleman Dome producing trend of an echelon folds which comprise the first line of folding down the northeast flank of the Wind River Mountains. The structural style exposed in the Palozoic reservoir rocks of Sheep Mountain may serve as a model for the other structural features in the Wind River Basin. As in the case of the Derby Dome and Winkleman Dome, Sheep Mountain is typically asymmetric to the southwest. Local east-directed thrusts exposed in the core of the anticline place Pennsylvania over Permian age rocks. A major change in the trend of the anticlinal crest within Sheep Mountain, suggests development of separate left-stepping en echelon closures at depth. The northwest end of Sheep Mountain also forms a left-stepping en echelon pattern with Derby Dome. The northwest plunge of Sheep Mountain is facilitated by compartmentalization ...

1988-01-01

250

Resource Conservation and Recovery Act corrective measures study: Area 6 decontamination pond facility, corrective action unit no. 92  

Energy Technology Data Exchange (ETDEWEB)

Corrective Action Unit (CAU) No. 92, the Area 6 Decontamination Pond Facility (DPF), is an historic disposal unit located at the Nevada Test Site (NTS) in Nye County, Nevada (Figures 1 - 1, 1-2, and 1-3). The NTS is operated by the U.S. Department of Energy, Nevada Operations Office (DOE/NV), which has been required by the Nevada Division of Environmental Protection (NDEP) to characterize the DPF under the requirements of the Resource Conservation and Recovery Act (RCRA) Part A Permit (NDEP, 1995) for the NTS and Title 40 Code of Federal Regulations (CFR) Part 265 (1996c). The DPF is prioritized in the Federal Facility Agreement and Consent Order (FFACO, 1996) but is governed by the permit. The DPF was characterized through sampling events in 1994, 1996, and 1997. The results of these sampling events are contained in the Final Resource Conservation and Recovery Act Industrial Site Environmental Restoration Site Characterization Report, Area 6 Decontamination Pond Facility, Revision I ...

1997-10-01

251

ESTABLISHING FINAL END STATE FOR A RETIRED NUCLEAR WEAPONS PRODUCTION REACTOR; COLLABORATION BETWEEN STAKEHOLDERS, REGULATORS, AND THE FEDERAL GOVERNMENT - 11052  

Science.gov (United States)

The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River (SRS) near Aiken, South Carolina. Nuclear weapons material production began in the early 1950s, utilizing five production reactors. In the early 1990s all SRS production reactor operations were terminated. The first reactor closure end state declaration was recently institutionalized in a Comprehensive Environmental Response and Compensation and Liability Act (CERCLA) Early Action Record of Decision. The decision for the final closure of the 318,000 square foot 105-P Reactor was determined to be in situ decommissioning (ISD). ISD is an acceptable and cost effective alternative to off-site disposal for the reactor building, which will allow for consolidation of remedial action wastes generated from other cleanup activities within the P Area. ISD is considered protective by the regulators, U. S. Environmental ...

2010-11-17

252

Disorders of brain development and phakomatosis  

International Nuclear Information System (INIS)

Full text: Disorders of brain development and phakomatosis are resulting from disturbed embryonic-foetal development One third of all major embryological anomalies involve CNS, and over 2000 different anomalies have been described. Anomalies of the brain often cause foetal and neonatal death, and mental and physical retardation in pediatric group. The majority of disorders of brain development and phakomatosis are idiopathic, and most of them are not hereditary or familial. Ultrasonography plays the important role in screening foetal and neonatal brain, but after closure of fontanels it is difficult to find the acoustic window. CT has limited contrast resolution, and disadvantage exposing infant to ionizing radiation. It is helpful to demonstrate the presence of calcifications. MR imaging has proved to be a diagnostic tool of major importance in children with disorders of brain development and phakomatosis. The excellent grey/white matter differentiation and ...

253

Closure relations for the multi-species Euler system. Construction and study of relaxation schemes for the multi-species and multi-components Euler systems; Relations de fermeture pour le systeme des equations d'Euler multi-especes. Construction et etude de schemas de relaxation en multi-especes et en multi-constituants  

Energy Technology Data Exchange (ETDEWEB)

After having recalled the formal convergence of the semi-classical multi-species Boltzmann equations toward the multi-species Euler system (i.e. mixture of gases having the same velocity), we generalize to this system the closure relations proposed by B. Despres and by F. Lagoutiere for the multi-components Euler system (i.e. mixture of non miscible fluids having the same velocity). Then, we extend the energy relaxation schemes proposed by F. Coquel and by B. Perthame for the numerical resolution of the mono-species Euler system to the multi-species isothermal Euler system and to the multi-components isobar-isothermal Euler system. This allows to obtain a class of entropic schemes under a CFL criteria. In the multi-components case, this class of entropic schemes is perhaps a way for the treatment of interface problems and, then, for the treatment of the numerical mixture area by using a Lagrange + projection scheme. Nevertheless, we have to find a good projection ...

2001-07-01

254

Nuclear structure of light Ca and heavy Cr isotopes  

Energy Technology Data Exchange (ETDEWEB)

In the present thesis, the shell structure in exotic nuclei has been investigated. The focus of the work was on finding new experimental data in neutron-rich Cr and proton-rich Ca isotopes. The investigation of light Ca isotopes concentrated on the nucleus {sup 36}Ca which was produced in a knockout reaction from a radioactive {sup 37}Ca beam. For {sup 36}Ca, the excitation energy of the first 2{sup +} state has been measured for the first time. Furthermore, momentum distributions were analyzed using a Monte-Carlo simulation of the knockout reaction. This analysis yielded the contributions of neutrons from individual orbitals to the total knockout cross section. In principle, these may be used to calculate spectroscopic factors, but such a calculation is hampered by difficulties of present knockout-reaction models in predicting precise single-particle cross sections. The measured branching ratio to the ground and excited states, on the other hand, is close to the predicted value. A ...

2007-07-01

255

Van Der Pol model of a Cerenkov maser  

Energy Technology Data Exchange (ETDEWEB)

A non-linear analysis of a Cerenkov maser is presented. The system consists of a ring configuration of a cylindrical waveguide filled with a dielectric material. A single transverse-magnetic mode is assumed to propagate in the system. A low-density pencil electron beam travels in part of the ring, confined by a strong axial magnetic field. Using the single-particle description for the beam and the wave equation for the field, we obtain a set of two coupled non-linear differential equations describing the slowly varying amplitude and phase of the electromagnetic mode. The gain per path is assumed to be small and the spatial growth of the field is neglected. The resulting time dependent amplitude includes the exponential gain of the linear stage and the saturation to its maximum value. The time dependent frequency is also calculated. The two equations are combined to a single Van Der Pol equation with a non-linear restoring force. This ...

1995-12-31

256

UHRF1, a modular multi-domain protein, regulates replication-coupled crosstalk between DNA methylation and histone modifications  

Science.gov (United States)

Cytosine methylation in DNA is a major epigenetic signal, and plays a central role in propagating chromatin status during cell division. However the mechanistic links between DNA methylation and histone methylation are poorly understood. A multi-domain protein UHRF1 (ubiquitin-like, containing PHD and RING finger domains 1) is required for DNA CpG maintenance methylation at replication forks, and mouse UHRF1-null cells show enhanced susceptibility to DNA replication arrest and DNA damaging agents. Recent data demonstrated that the SET and RING associated (SRA) domain of UHRF1 binds hemimethylated CpG and flips 5-methylcytosine out of the DNA helix, whereas its tandom tudor domain and PHD domain bind the tail of histone H3 in a highly methylation sensitive manner. We hypothesize that UHRF1 brings the two components (histones and DNA) carrying appropriate markers (on the tails of H3 and hemimethylated CpG sites) ready to be assembled into a ...

2009-01-01

257

The viscous overstability, nonlinear wavetrains, and finescale structure in dense planetary rings  

CERN Document Server

This paper addresses the fine-scale axisymmetric structure exhibited in Saturn's A and B-rings. We aim to explain both the periodic microstructure on 150-220m, revealed by the Cassini UVIS and RSS instruments, and the irregular variations in brightness on 1-10km, reported by the Cassini ISS. We propose that the former structures correspond to the peaks and troughs of the nonlinear wavetrains that form naturally in a viscously overstable disk. The latter variations on longer scales may correspond to modulations and defects in the wavetrains' amplitudes and wavelength. We explore these ideas using a simple hydrodynamical model which captures the correct qualitative behaviour of a disk of inelastically colliding particles, while also permitting us to make progress with analytic and semi-analytic techniques. Specifically, we calculate a family of travelling nonlinear density waves and determine their stability properties. Detailed numerical simulations that confirm our ...

2009-01-01

258

Si3C2-rings: from a nonconjugated trisilacyclopentadiene to an aromatic trisilacyclopentadienide and cyclic disilenide.  

Science.gov (United States)

1,2,3-Trisilacyclopenta-1,4-diene 2, featuring three skeletal Si atoms in the five-membered ring, was synthesized by the thermolysis of the 1,2,3-trisilabicyclo[1.1.0]butane derivative 1 at 130 degrees C in the presence of hex-3-yne. Possessing the properties of nonconjugated cyclopentadiene, 2 readily underwent reduction with KC(8), which was followed by treatment with LiBr to form the lithium salt of 1,2,3-trisilacyclopentadienide 3(-)*[Li(+)(thf)], from which the ketone-coordinated derivative 3(-)*[Li(+)(O=C(t)Bu(2))] was prepared. Both 3(-)*[Li(+)(L)] (L = thf, O=C(t)Bu(2)) are classified as novel 6pi-electron aromatic systems based on their characteristic X-ray crystal and NMR spectral data. Addition of 12-crown-4 to 3(-)*[Li(+)(thf)] resulted in the unexpected formation of 4(-)*[Li(+)(12-crown-4)(2)], featuring the unprecedented cyclic disilenide ion 4(-). PMID:19378994

2009-05-13

259

Rice RING protein OsBBI1 with E3 ligase activity confers broad-spectrum resistance against Magnaporthe oryzae by modifying the cell wall defence  

British Library Electronic Table of Contents (United Kingdom)

Emerging evidence suggests that E3 ligases play critical roles in diverse biological processes, including innate immune responses in plants. However, the mechanism of the E3 ligase involvement in plant innate immunity is unclear. We report that a rice gene, OsBBI1, encoding a RING finger protein with E3 ligase activity, mediates broad-spectrum disease resistance. The expression of OsBBI1 was induced by rice blast fungus Magnaporthe oryzae, as well as chemical inducers, benzothiadiazole and salicylic acid. Biochemical analysis revealed that OsBBI1 protein possesses E3 ubiquitin ligase activity in vitro. Genetic analysis revealed that the loss of OsBBI1 function in a Tos17-insertion line increased susceptibility, while the overexpression of OsBBI1 in transgenic plants conferred enhanced resi...

2011-01-01

260

Retuning the APS storage ring for better chromaticity correction.  

Energy Technology Data Exchange (ETDEWEB)

When the APS storage ring was retuned to provide smaller {beta}{sub y} values in the insertion straight sections, it was necessary to increase the vertical tune by at least two units. Since the design values for the horizontal and vertical tunes are 35.22 and 16.30, respectively, this put the tunes dangerously close to the sextupole 2v{sub y}-v{sub x} coupling resonance. The large injection horizontal oscillations could couple to the vertical plane and exceed the 5-mm vertical apertures that exist in some of the insertion straight sections. To avoid this resonance, the vertical tune was raised beyond the resonance to 19.30. The result was a reduction in the ability of the chromaticity sextuples to correct the chromaticity. Recent investigation has shown that the chromaticity correction capability of the sextuples can be greatly increased by a modest increase in the horizontal tune. Increasing the horizontal tune by one unit and reducing the vertical tune by three ...

1999-09-11

261

Platelet thrombosis in cardiac-valve prostheses  

International Nuclear Information System (INIS)

The contribution of platelets and clotting factors in thrombosis on cardiovascular prostheses had been quantified with several tracers. Thrombus formation in vivo could be measured semiquantitatively in animal models and patients with indium-111, Technetium-99m labeled platelets, iodine-123, iodine-131 labeled fibrinogen, and In-111 and Tc-99m labeled antibody to the fibrinogen-receptor on the platelet- membrane, or fibrin. The early studies demonstrated that certain platelet-inhibitors, e.g. sulfinpyrazone, aspirin or aspirin- persantine increased platelet survival time with mechanical valves implanted in the baboon model and patients. Thrombus localization by imaging is possible for large thrombus on thrombogenic surface of prosthesis in the acute phase. The majority of thrombus was found in the sewing ring (Dacron) in the acute phase in both the mechanical and tissue valves. The amount of retained thrombus in both mechanical and tissue valves in our one-day ...

1989-06-08

262

Performance of hybrid ball bearings in oil and jet fuel  

Energy Technology Data Exchange (ETDEWEB)

A 308-size hybrid ball bearing, with ceramic balls and steel rings, was tested using a diester oil and gas turbine fuel as lubricants at several speeds and loads. Heat generation data from this test work was then correlated with the heat generation model from a widely used computer code. The ability of this hybrid split inner ring bearing design to endure thrust reversals, which are expected in many turbine applications, was demonstrated. Finally, the bearing was successfully endurance tested in JP-10 fuel for 25 hours at 7560 N axial load and 36,000 rpm. This work has successfully demonstrated the technology necessary to use fuel-lubricated hybrid bearings in limited-life gas turbine engine applications such as missiles, drones, and other unmanned air vehicles (UAVs). In addition, it has provided guidance for use in designing such bearing systems. As a result, the benefits of removing the conventional oil lubricant system, i.e., design ...

1992-07-01

263

On the application of Allan variance method for Ring Laser Gyro performance characterization  

Energy Technology Data Exchange (ETDEWEB)

This report describes the method of Allan variance and its application to the characterization of a Ring Laser Gyro`s (RLG) performance. Allan variance, a time domain analysis technique, is an accepted IEEE standard for gyro specifications. The method was initially developed by David Allan of the National Bureau of Standards to quantify the error statistics of a Cesium beam frequency standard employed as the US Frequency Standards in 1960`s. The method can, in general, be applied to analyze the error characteristics of any precision measurement instrument. The key attribute of the method is that it allows for a finer, easier characterization and identification of error sources and their contribution to the overall noise statistics. This report presents an overview of the method, explains the relationship between Allan variance and power spectral density distribution of underlying noise sources, describes the batch and recursive implementation approaches, validates ...

1993-10-15

264

Longitudinal and transverse dynamics of a free electron laser based on a storage ring of second and third generation  

International Nuclear Information System (INIS)

This work aims at improving the understanding of the dynamics of a Free Electron Laser (FEL) based on a storage ring. A new phenomenon of saturation by the electron bunch transverse dimensions is pointed out, during the FEL operation with a magnetic optics ''low emittance''. A part of this thesis work concerns the study of the longitudinal dynamics of the FEL depending on a parameter: the detuning between the pass frequency of the electrons and the back and return frequency of the laser pulse in the optical cavity. This study shows that the FEL presents a pulsed or a steady state behavior depending on the detuning. Besides, a spectro-temporal behavior of the FEL is pointed out showing the FEL pulse substructures and holes in the spectrum. Another part of this work concerns the response of the resonant FEL system, when a perturbation is applied on the gain. Under the effect of a modulation, the FEL can present a periodic or chaotic regime. The analysis of these ...

265

Influence of some processing factors on susceptibility to caustic stress corrosion cracking of modified alloy 800  

International Nuclear Information System (INIS)

The influence of some processing factors such as cold work and heat treatment on the susceptibility to caustic stress corrosion cracking (SCC) of modified alloy 800, referred to alloy 800 M, in a boiling solution of 50%NaOH + 0.3%SiO_2+0.3%Na_2S_2O_3 was investigated by means of microstructure examination, tensile test, stress analysis, SCC test of C-rings, Auger electron spectroscopy (AES) and corrosion mode. Cold work led to lengthening of grains, decrease in ductility, increase in strength, residential stress and susceptibility to SCC. With increasing temperature of heat treatment on alloy 800 M after cold work, grains became bigger, ductility increased but strength, residential stress and susceptibility to SCC decreased. SCC cracks on C-ring specimens initiated from pitting and propagated along grain boundaries. AES analysis indicates that the surface films on alloy 800M are enriched in nickel and depleted in iron and chromium. (authors)

2005-07-01

266

Fine-ceramic anitifriction bearings  

Energy Technology Data Exchange (ETDEWEB)

Ceramic antifriction bearings were introduced in excellent characterics and application. In main shaft use bearings of the machine tool, to be heightened in efficiency and accuracy by the heightening in speed, centrifugal load to the outer ring is not negligible to shorten the bearing in life. Also ball bearings with a contact angle are easily corroded by a very strong revolution slide due to the gyromoment. The use of such light weight material as silicon nitride's can design the lengthening in life. Also the utilization of high rigidity can prevent the inner ring from expanding by centrifugal force and enable the machining to be with a high accuracy. Ceramic rolling element is excellent also in backing resistant property and effective on the oily film cut. With heat resistant property, it maintains hardness even at high temperature. Such excellent characteristics being utilized, the fine ceramic antifriction bearing is used for the ...

1989-08-01

267

Experimental investigation of the thermal contact resistance of a space-use deep groove ball bearing. Uchuyo fukamizo tamajikuukenai no sesshoku netsu teiko ni kansuru jikkenteki kento  

Energy Technology Data Exchange (ETDEWEB)

The thermal contact resistance between balls and inner and outer rings of thermally steady space-use deep groove ball bearings was studied experimentally to verify the validity of the previously proposed calculation method for the resistance. The 440C stainless steel single row bearing was used for measuring its steady state temperature distributions in a vacuum environment under axial, radial and combined load conditions. As a result, the experimental results of the resistance well agreed with calculated ones under each load condition resulting in the sufficient validity at nearly the same surface roughness. It was necessary to apply a static equivalent radial load to calculation under the combined load that a contact angle is larger than the angle of resultant force dependent on both load components. In experiments under only radial load, measurement of outer ring temperatures was necessary at some points with no contact with balls to avoid ...

1992-12-05

268

Electron beam qualities with and without free electron laser oscillations in the compact storage ring NIJI-IV  

International Nuclear Information System (INIS)

The electron-beam qualities with and without free electron laser (FEL) oscillations were investigated in the compact storage ring NIJI-IV. The peak-electron density in a bunch was suppressed by beam instabilities, so that it was limited to about 1.0 x 10"1"7 m"-"3. The maximum FEL gain estimated for 215 and 300 nm using a well-known one-dimension theory was about 2.8% and 4.6%. The cavity loss at 300 nm was evaluated to be about 2% from the threshold beam current. The bunch length and energy spread with FEL oscillations increased by 1.3 times or more due to bunch heating. The ratio of the FEL gain to a cavity loss estimated from the beam qualities with and without FEL oscillations was almost in accord with the ratio evaluated directly with the measured data of the FEL gain and the cavity loss. (author)

2003-09-01

269

Effects of DC plasma nitriding parameters on microstructure and properties of 304L stainless steel  

International Nuclear Information System (INIS)

A wear-resistant nitrided layer was formed on a 304L austenitic stainless steel substrate by DC plasma nitriding. Effects of DC plasma nitriding parameters on the structural phases, micro-hardness and dry-sliding wear behavior of the nitrided layer were investigated by optical microscopy, X-ray diffraction, scanning electron microscopy, micro-hardness testing and ring-on-block wear testing. The results show that the highest surface hardness over a case depth of about 10 #mu#m is obtained after nitriding at 460 deg. C. XRD indicated a single expanded austenite phase and a single CrN nitride phase were formed at 350 deg. C and 480 deg. C, respectively. In addition, the S-phase layers formed on the samples provided the best dry-sliding wear resistance under the ring-on-block contact configuration test.

2009-03-01

270

Detection and classification of bearing flaking using kullback discrimination information; Kullback shikibetsu johoryo (KDI) wo mochiita jikuuke no tendomen hakuri no kenchi to shikibetsu  

Energy Technology Data Exchange (ETDEWEB)

Since bearing is in wide use as basic parts for rotary machines, detection and diagnosis of its defects are important in practical use. To discriminate defect portions by early detection of roller bearing flaking, the conventional parameter method using peakedness is poor. Thus to directly obtain difference in waveform, the new method was applied to such detection which uses KDI as the scale of a difference in waveform, and a most neighborhood classification rule based on KDI. The detection and discrimination abilities of this method was studied mainly in experiment. The experiment used a bench scale rotor and a supporting bearing, and attempted detection and discrimination of no flaking, outer ring flaking and inner ring flaking. As a result, this method could detect and discriminate fine flaking which was never detected by conventional method. Since selection of standard data is essential for this method, a distance ratio was introduced as ...

1998-06-15

271

Cyclopalladated 2-phenyldihydrooxazole complexes with ethylenediamine, 2,2?-bipyridine, and bridging acetate ligands  

British Library Electronic Table of Contents (United Kingdom)

The 1H NMR, electronic absorption, and luminescence spectra, as well as voltammograms of the reduction and oxidation of the complexes [Pd(C?N)(N?N)]ClO4 and [Pd(C?N)(?-OOCCH3)]2 [where (C?N)? is deprotonated 2-phenyl-4,5-dihydro-1,3-oxazole, and N?N is ethylenediamine or 2,2?-bipyridine (bpy)] were compared. Magnetic nonequivalence of protons in the dihydrooxazole ring and upfield shift of the corresponding signals were observed as a result of anisotropic effect of the ring current in palladated phenyl substituents in the [Pd(C?N)(?-OOCCH3)]2 complex having a C 2 symmetry. One-electron reduction wave of [Pd(C?N)bpy]+ was assigned to ligand-centered electron transfer to the ?* orbital of 2,2?-bipyridine, and two oxidation waves of [Pd(C?N)(?-OOCCH3)]2 were attributed to successive one-elect...

2011-01-01

272

Crystal structures of two novel sulfonylurea herbicides in complex with Arabidopsis thaliana acetohydroxyacid synthase  

Energy Technology Data Exchange (ETDEWEB)

Acetohydroxyacid synthase (AHAS; EC 2.2.1.6) is the first enzyme in the biosynthetic pathway of the branched-chain amino acids. It catalyzes the conversion of two molecules of pyruvate into 2-acetolactate or one molecule of pyruvate and one molecule of 2-ketobutyrate into 2-aceto-2-hydroxybutyrate. AHAS requires the cofactors thiamine diphosphate (ThDP), Mg{sup 2+} and FAD for activity. The herbicides that target this enzyme are effective in protecting a broad range of crops from weed species. However, resistance in the field is now a serious problem worldwide. To address this, two new sulfonylureas, monosulfuron and monosulfuron ester, have been developed as commercial herbicides in China. These molecules differ from the traditional sulfonylureas in that the heterocyclic ring attached to the nitrogen atom of the sulfonylurea bridge is monosubstituted rather than disubstituted. The structures of these compounds in complex with the catalytic subunit of Arabidopsis ...

2009-08-17

273

Collection and analysis of particulate from the DIII-D Tokamak  

International Nuclear Information System (INIS)

Particulate (i.e. tokamak dust) has been collected from the DIII-D tokamak located at General Atomics in San Diego, CA, USA. Two methods were used to collect particulate with the goal of preserving the particle size distribution and physical characteristics of the particulate. Vacuum collection on substrates and adhesion removal with metallurgical replicating tape were chosen as non-intrusive sampling methods. Sampling was completed in four toroidal locations of the machine; the 0-90 area, the 90-180 area, the 180-270 area, and the 270-360 area. The 0 direction designates the north side of the DIII-D machine. Four tiles in each area were sampled; the first vertical tile above the floor on the centerpost, a floor tile next to the center post, a tile on the isolated ring, and the first tile up from the isolated ring on the divertor. In addition, samples were collected from underneath the floor tiles at the 275 and the 75 locations. The count ...

1998-09-01

274

Beam stabilization in SPring-8 linac for top-up injections into storage rings  

International Nuclear Information System (INIS)

The SPring-8 linac has been improved to realize stable top-up injection into the SPring-8 and the NewSUBARU storage rings. The beam energy instability of 0.02% rms in the long term was achieved by means of reducing RF variations, providing beam energy compensation, reinforcement of monitor systems and introduction of beam feedback controls: Variations in the RF power and phase have been reduced by improving the voltage regulation system for the klystron modulator, and by stabilizing the temperature drift of the atmosphere and cooling water in order to reduce the phase variation. A new synchronous oscillator synchronizes a beam trigger pulse and a 2856 MHz reference signal, reducing variation in the beam charge. A beam energy compression system (ECS) was installed to compensate for accidental energy variation and reduce the energy spread. Beam feedback controls compensate for residual long-term variations of beam trajectory and energy. (author)

2006-03-01

275

An immunochemical approach to the study of DNA damage and repair. Technical progress report, May 1, 1989--April 30, 1992  

Energy Technology Data Exchange (ETDEWEB)

The overall objective of this project has been to develop immunochemical methods to quantitate unique DNA base damages in order to facilitate studies on radiation-induced damage production and repair. Specifically, we have been using antibodies raised to damaged bases to quantitate unique lesions in model systems in order to evaluate their potential biological consequences. Our approach has been to synthesize modified nucleotides or nucleosides, conjugate them to protein carriers, and use the conjugates as immunogens in rabbits or to prepare monoclonal antibodies. We have been studying damages that are stable radiolysis products found in X-irradiated DNA and thus of potential biological consequence. Our aim is to build an in vitro and in vivo data base on the interactions between model DNA lesions and such cellular enzymes as DNA polymerases and repair endonucleases. Initial studies have focused on pyrimidine ring saturation products (thymine glycol.and ...

1992-05-01

276

An immunochemical approach to the study of DNA damage and repair  

Energy Technology Data Exchange (ETDEWEB)

The overall objective of this project has been to develop immunochemical methods to quantitate unique DNA base damages in order to facilitate studies on radiation-induced damage production and repair. Specifically, we have been using antibodies raised to damaged bases to quantitate unique lesions in model systems in order to evaluate their potential biological consequences. Our approach has been to synthesize modified nucleotides or nucleosides, conjugate them to protein carriers, and use the conjugates as immunogens in rabbits or to prepare monoclonal antibodies. We have been studying damages that are stable radiolysis products found in X-irradiated DNA and thus of potential biological consequence. Our aim is to build an in vitro and in vivo data base on the interactions between model DNA lesions and such cellular enzymes as DNA polymerases and repair endonucleases. Initial studies have focused on pyrimidine ring saturation products (thymine glycol.and ...

1992-05-01

277

Aluminum siting in mordenite and dealumination mechanism  

Science.gov (United States)

The dealumination of mordenite by acidification (HCl, HNO/sub 3/) and by SiCl/sub 4/ and steaming treatments is followed by high-resolution magic-angle-spinning solid-state /sup 29/Si and /sup 27/Al NMR spectroscopy. The combined use of these techniques leads to the determination of the silicon-aluminum ordering. It is demonstrated that aluminum atoms preferentially occupy tetrahedral positions in the four-membered rings of the mordenite structure. In addition, a mechanism of dealumination can be inferred, consisting in removing the aluminum atoms two by two from the four-membered rings. It is also possible to compute the number of SiOH groups left in the unit cell after the progressive removal of aluminum atoms: four groups per extracted Al atom are generated in the beginning of dealumination and this number gradually decreases to two, suggesting that a structural reorganization must necessarily occur for substantial dealumination. These ...

1986-10-09

278

3. 3-Bis (azidomethyl) oxetane (BAMO)-based propellants. (1). ; Synthesis and characterizatio of BAMO-based polymers. BAMO kei suishin yaku no kenkyu. (1). ; BAMO kei jugotai no gosei to tokusei hyoka  

Energy Technology Data Exchange (ETDEWEB)

Concerning high performance composite solid propellant BAMO and BAMO-based copolymers, synthetic method and properties of them were studied. Comparison graph of theoretical specific impulse for various propellants were shown, by that, reason why highest specific impulse BAMO was selected as direction of the study. As the orientation of synthesis, those were indicated that radicals at both ends should be hydroxyl so as urethane bonding was available, that liquid at normal temperature was required for easy handling, and that glass transition temperature is required to be low enough. Synthesis was conducted by ring-opening polymerization of ring ether detail procedures of which were explained. Measurements of properties was performed for thermochemical properties, thermal decomposition, combution heat, and friction sensitivity test to confirm safety. As the result, those were understood that thermal decomposition was divided into two phases, rapid ...

1990-08-31

279

Wear resistance of a laser surface alloyed Ti-6Al-4V alloy  

Energy Technology Data Exchange (ETDEWEB)

Laser surface alloying with gaseous nitrogen was utilized to improve the wear resistance of a Ti-6Al-4V alloy. Wear-resistant composite coatings reinforced by hard TiN dendrites were produced 'in-situ' on a substrate of a Ti-6Al-4V alloy. The hardness and wear resistance of the laser alloyed coating under two-body abrasive and block-on-ring full-sliding wear conditions were significantly enhanced. (orig.)

2000-08-01

280

Structure, reactivity, and biological properties of hidantoines; Estrutura, reatividade e propriedades biologicas de hidantoinas  

Energy Technology Data Exchange (ETDEWEB)

Hydantoin (imidazolidine-2,4-dione) is a 2,4-diketotetrahydroimidazole discovered by Baeyer in 1861. Thiohydantoins and derivatives were prepared, having chemical properties similar to the corresponding carbonyl compounds. Some biological activities (antimicrobial, anticonvulsant, schistosomicidal) are attributed to the chemical reactivity and consequent affinity of hydantoinic rings towards biomacromolecules. Therefore, knowledge about the chemistry of hydantoins has increased enormously. In this review, we present important aspects such as reactivity of hydantoins, acidity of hydantoins, spectroscopy and crystallographic properties, and biological activities of hydantoin and its derivatives. (author)

2008-07-01

281

String theory, black holes, and SL(2,R) current algebra  

International Nuclear Information System (INIS)

We analyse in detail the SL(2, R) black hole by extending standard techniques of Kac-Moody current algebra to the non-compact case. We construct the elements of the ground ring and exhibit W_#infinity# type structure in the fusion algebra of the discrete states. As a consequence, we can identify some of the exactly marginal deformations of the black hole. We show that these deformations alter not only the spacetime metric but also turn on non-trivial backgrounds for the tachyon and all of the massive modes of the string. (orig.).

1993-05-01

282

Steady-state neutronic investigations to the accident of water ingress in systems with pebble-bed high-temperature gas-cooled reactor fuel  

Energy Technology Data Exchange (ETDEWEB)

For light water reactors, loss of coolant is an important point in safety analysis, whereas for gas-cooled reactors the ingress of water into the core region is an incident of safety relevance. The applicability of the computer code system GAMTEREX to pebble beds of spherical high-temperature gas-cooled reactor fuel elements with simulated water ingress is verified by experiment. The measurements were performed at a Siemens-Argonaut reactor, using its ring core as a driver zone for a pebble-bed core in the center of the reactor.

1987-09-01

283

Stability against temperature variations at the ALS  

Energy Technology Data Exchange (ETDEWEB)

We have studied the effects of temperature fluctuations on the Advanced Light Source (ALS). By modeling the storage ring support structure, we find that fluctuations of {plus minus}2 to 3deg C in the tunnel will cause photon beam motion of the order of the beam size. Temperature stabilization at this level will allow the residual motion of the photon beams to be reduced by a second level of active feedback, operating on signals from photon beam position monitors. Air temperature in the experimental area and the temperature of cooling water serving the beamlines should be constant to {plus minus}1deg C. This will provide a suitable environment for experiments. (orig.).

1990-05-20

284

Review of ion accelerators  

Energy Technology Data Exchange (ETDEWEB)

The field of ion acceleration to higher energies has grown rapidly in the last years. Many new facilities as well as substantial upgrades of existing facilities have extended the mass and energy range of available beams. Perhaps more significant for the long-term development of the field has been the expansion in the applications of these beams, and the building of facilities dedicated to areas outside of nuclear physics. This review will cover many of these new developments. Emphasis will be placed on accelerators with final energies above 50 MeV/amu. Facilities such as superconducting cyclotrons and storage rings are adequately covered in other review papers, and so will not be covered here.

1990-06-01

285

Requirements and guidelines for NSLS experimental beam line vacuum systems: Revision A  

Energy Technology Data Exchange (ETDEWEB)

Requirements are provided for NSLS beam line front ends and vacuum interlocks. Guidelines are provided for UHV beam line vacuum systems, including materials, vacuum hardware (pumps, valves, and flanges), acoustic delay lines and beam line fast valves, instrumentation, fabrication and testing, and the NSLS cleaning facility. Also discussed are the design review for experimenters' equipment that would be connected to the NSLS and acceptance tests for any beam line to be connected with the ring vacuum. Also appended are a description of the acoustic delay line as well as the NSLS vacuum standards and NSLS procedures. (LEW)

1986-10-01

286

Real time neutron diffraction study on the intercalation of deuterobenzene into RbC/sub 24/  

Energy Technology Data Exchange (ETDEWEB)

The reaction of RbC/sub 24/ with C/sub 6/D/sub 6/ vapour was studied by neutron diffraction on a time scale of 5 min/spectrum. As for the reaction of KC/sub 24/, a second stage phase RbC/sub 24/(C/sub 6/D/sub 6/)sub(y) is initially formed and subsequently transformed into a first stage phase. Model calculations indicate that the benzene rings are canted against the graphite planes both in the first and in the second stage phase.

1983-11-01

287

Quantum theory of the interaction of Josephson junctions with non-classical microwaves  

Energy Technology Data Exchange (ETDEWEB)

We present a study of the interaction between Josephson junctions in circular superconducting rings and non-classical microwaves, treating both quantum mechanically. A Hamiltonian that describes both inductive and capacitive coupling between the two systems is derived within the external field approximation. Other Hamiltonians which go beyond the external field approximation, and describe explicitly the interaction of the quantum circuit that produces the non-classical microwaves with the Josephson junction circuit, are also presented. A comparison between current experiments which use classical electromagnetic fields and the proposed experiments that use non-classical microwaves, is made. (orig.) With 6 figs., 32 refs.

1997-01-01

288

Progress in construction of the LHC  

CERN Document Server

The Large Hadron Collider (LHC) project, approved by the CERN Council in December 1994, has now fully entered its construction phase, with the detailed technical definition of the major systems, and the adjudication of a number of large procurement contracts. We first recall the main features and characteristics of the LHC, report on the advances in definition of the layout and optics as well as on preparation of the injector complex, and review recent progress in the key technical systems of the main ring: magnets, cryogenics and vacuum, as well as civil construction, which has started following acceptance by authorities in the Host States.

1998-01-01

289

Polarizing a stored proton beam by spin flip?  

International Nuclear Information System (INIS)

We discuss polarizing a proton beam in a storage ring, either by selective removal or by spin flip of the stored ions. Prompted by recent, conflicting calculations, we have carried out a measurement of the spin-flip cross section in low-energy electron-proton scattering. The experiment uses the cooling electron beam at COSY as an electron target. The measured cross sections are too small for making spin flip a viable tool in polarizing a stored beam. This invalidates a recent proposal to use co-moving polarized positrons to polarize a stored antiproton beam.

2009-04-27

290

Performance Comparisons of PSO based Clustering  

CERN Document Server

In this paper we have investigated the performance of PSO Particle Swarm Optimization based clustering on few real world data sets and one artificial data set. The performances are measured by two metric namely quantization error and inter-cluster distance. The K means clustering algorithm is first implemented for all data sets, the results of which form the basis of comparison of PSO based approaches. We have explored different variants of PSO such as gbest, lbest ring, lbest vonneumann and Hybrid PSO for comparison purposes. The results reveal that PSO based clustering algorithms perform better compared to K means in all data sets.

2010-01-01

291

Operational Experience with LHC Collimation  

CERN Document Server

A first sub-set of the collimation system has been installed for the 2008 first beam commissioning of the LHC. It included 88 collimators around the ring and the two injection lines. Each collimator has two jaws for which must be controlled and monitored with high precision. The LHC collimation system was put into operation from July to October 2008. The installed system is described and first results from system operation without and with beam are presented. It is shown that the LHC collimation system achieved the specified accuracy and reproducibility of jaw positioning. Next steps in collimation commissioning are described and planned system upgrades for high beam intensities are outlined.

2009-01-01

292

Nondestructive testing of metal coating thickness and control of chemical composition using radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

The principle is described of a method using low-activity emitters as the primary radiation source for analysis. The selection of the radiation source and the detection methods including the assessment of the applicability of various radiation detectors are discussed. The benefits and the constraints of the method are considered. Practical examples are presented showing the application possibilities of the method for testing the thickness of bearing layers, piston ring coats, lead layers, etc. The possibility is shown of applying the rapid test for the composition of tungsten and chromium alloyed metal materials in testing complex systems. (J.K.).

1974-12-03

293

Mechanism of biodegradation of paraquat by Lipomyces starkeyi  

Energy Technology Data Exchange (ETDEWEB)

The biodegradation of ring-/sup 14/C- and methyl-/sup 14/C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO/sub 2/. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.

1985-05-01

294

Mechanism of biodegradation of paraquat by Lipomyces starkeyi  

International Nuclear Information System (INIS)

The biodegradation of ring-"1"4C- and methyl-"1"4C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO_2. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.

295

Interactive Orbit Control in MATLAB  

Energy Technology Data Exchange (ETDEWEB)

Recent advances in steering algorithms have made it possible to accurately control electron beam position in storage rings, implement fast and slow feedback systems, and in some cases detect hardware errors. In practice, however, the program operator would like to reduce the overhead of selecting variables and constraints and to easily view the data. To simplify the process, we constructed an interactive orbit control program in MATLAB [1]. The program modules are easily adapted to new algorithms or beam lines. This paper describes the program functionality and architecture.

2001-07-06

296

Improved beam confinement in the modified betatron with strong focusing  

International Nuclear Information System (INIS)

The lifetime of the circulating electron beam in the Naval Research Laboratory modified betatron has been increased by more than 2 orders of magnitude with the addition of strong focusing windings to the device. The injected beam consistently spirals from the injector to the minor axis and is trapped. The #approx#0.5-kA trapped electron ring has been accelerated above 10 MeV from the injection energy of 0.5 to 0.6 MeV. The beam acceleration has been confirmed not only by the x-ray attenuation technique but also with the detection of photoneutrons.

297

Freezing phenomena in ice-water systems  

Energy Technology Data Exchange (ETDEWEB)

The characteristics of solidification and melting are reviewed. The properties of water and ice and the phase diagram of water are discussed with special emphasis on ice density. A concise account of the freezing process and the Stefan problem is presented. To this end, the four stages of freezing are identified, supercooling, nucleation and the formation of dendritic ice, the growth of concentric rings of solid ice at 0{sup o}C and the final cooling of the solid ice are treated in some detail. The subject of bursting of pipes is given particular emphasis. Attention is drawn to a common misconception on pipe bursting and to misleading relationships for the computation of freezing time for ice blockage. Several current applications of melting and freezing systems are outlined. (author)

2002-09-01

298

First results from the Lund NMP particle detector system  

International Nuclear Information System (INIS)

The design and first results from a Double Sided Silicon Strip Detector (DSSSD) recently installed at the Lund Nuclear Microprobe facility (NMP) are presented. The detector has 64 sector strips and 32 ring strips, which in combination give more than 2000 detector cells, each with characteristics comparable with a standard surface barrier detector (SBD). The detector has been tested both with radioactive sources and with different ion beams and energies. The most striking features are the high rate virtually pile-up free operation and also the possibility of detailed measurement of angular distributions.

2009-06-15

299

First results from the Lund NMP particle detector system  

British Library Electronic Table of Contents (United Kingdom)

The design and first results from a Double Sided Silicon Strip Detector (DSSSD) recently installed at the Lund Nuclear Microprobe facility (NMP) are presented. The detector has 64 sector strips and 32 ring strips, which in combination give more than 2000 detector cells, each with characteristics comparable with a standard surface barrier detector (SBD). The detector has been tested both with radioactive sources and with different ion beams and energies. The most striking features are the high rate virtually pile-up free operation and also the possibility of detailed measurement of angular distributions.

2009-01-01

300

Final design and manufacturing of the Cryolegs of the W7-X-superconducting coil support system  

Energy Technology Data Exchange (ETDEWEB)

One of the most complicated tasks during the assembly of the Wendelstein W7-X is the installation of the superconductive coil system. The entire magnet system is enclosed between the Outer Vessel and the plasma vessel in high vacuum at 4 K. The coils are supported by a support structure, the Central Support Structure (CSS). The CSS carries all 70 coils, and it is designed as a closed ring made of 5 modules (10 half modules). The whole structure is supported by 10 Cryolegs which rest on the machine base. This paper describes the final design and manufacture of these Cryolegs.

2008-12-15

301

Engineering electromagnetic response of composite terahertz metamaterial with broken symmetry  

Science.gov (United States)

We proposed and numerically investigated the influence of spatial symmetry on the terahertz frequency region response of composite planar metamaterials based on deformed split ring resonators. Compared with the original simple structures, the composite metamaterials with different spatial symmetries exhibited exotic electromagnetic properties. The electromagnetic response of a specific configuration with C4 symmetry was identical to the structure with simple lattice. Especially, for configurations with broken symmetry, very sharp Drude-like resonances with high quality factor were observed. The electric field and current distribution associated the resonances were analyzed for deep understanding of the underlying physical properties.

2011-09-01

302

Effect of Cl substituent in the aromatic tetracycline ring on its reactivity with solvated electrons  

Energy Technology Data Exchange (ETDEWEB)

Decomposition yields of tetracycline hydrochloride (TC.HCl) and chlorotetracycline hydrochloride (ClTC.HCl) in methanol solution saturated with Ar or N/sub 2/O were determined. Rate constants of the reaction esub(s)/sup -/ with some antibiotics were obtained. It was demonstrated by /sup 1/H NMR that the radical formed by degradation of 7-C-Cl group is recombined with the H atoms leading to ClTC.HCl being converted into tetracycline hydrochloride (TC.HCl).

1984-09-18

303

Childhood neuroborreliosis: clinicoradiological correlation  

Energy Technology Data Exchange (ETDEWEB)

We report the cranial CT and MRI findings in three children with Lyme disease (neuroborreliosis). The neuroimaging findings in children have been rarely reported. We found cranial MRI far superior to cranial CT. Ring-enhancing lesions have been described in acute disseminating encephalomyelitis and multiple sclerosis but not in neuroborreliosis. Although other infectious and inflammatory diseases cannot be excluded, Lyme disease should be included in the differential diagnosis and put forward as being the most likely diagnosis in the appropriate clinical setting. Gadopentetate dimeglumine is helpful in assessing the response to antibiotic treatment. (orig.)

1995-10-01

304

A study of aging effects in gas proportional detectors at the BAC calorimeter of the ZEUS experiment  

Energy Technology Data Exchange (ETDEWEB)

The multicell proportional chambers at the backing calorimeter of the ZEUS experiment at the storage ring HERA are supplied with a gas mixture of Ar/CO[sub 2] by an open gas system. Flow proportional counters with the build-up [sup 55]Fe sources are used as gas system monitoring detectors. The ZEUS experiment is planned to collect data for about 10 years. Therefore, the lifetime of the Ar/CO[sub 2] mixture should be known. In this paper, the results of laboratory tests and preliminary measurements of the aging effects for monitoring counters are presented. ((orig.))

1994-09-01

305

A real time neutron diffraction study on the intercalation of deuterobenzene into RbC_2_4  

International Nuclear Information System (INIS)

The reaction of RbC_2_4 with C_6D_6 vapour was studied by neutron diffraction on a time scale of 5 min/spectrum. As for the reaction of KC_2_4, a second stage phase RbC_2_4(C_6D_6)sub(y) is initially formed and subsequently transformed into a first stage phase. Model calculations indicate that the benzene rings are canted against the graphite planes both in the first and in the second stage phase. (Auth.).

1983-01-01

306

A correlation between electrochemical parameters and stress corrosion cracking of alloy 600 in high temperature caustic solution  

International Nuclear Information System (INIS)

The properties of the passive films formed on Alloy 600 at different applied potentials in 10% NaOH solution at 315 .deg. C was studied using in situ AC impedance and polarization measurements. The results were correlated with the stress corrosion cracking (SCC) behavior obtained from the C-ring tests in the same conditions. The change of the semiconductive property and the peak of relaxation time were observed at 0.2 V where the SCC rate showed a maximum. These results were also consistent with the prediction parameter for SCC obtained from fast and slow polarization scans.

2001-10-01

307

A combinatorial spanning tree model for knot Floer homology  

CERN Document Server

We iterate Manolescu's unoriented skein exact triangle in knot Floer homology with coefficients in the fraction field of the group ring (Z/2Z)[Z]. The result is a spectral sequence which converges to a stabilized version of delta-graded knot Floer homology. The (E_2,d_2) page of this spectral sequence is an algorithmically computable chain complex expressed in terms of spanning trees, and we show that there are no higher differentials. This gives the first combinatorial spanning tree model for knot Floer homology.

2011-01-01

308

Two-fluid modeling of condensation in the presence of noncondensables in two-phase channel flows  

Energy Technology Data Exchange (ETDEWEB)

Condensing two-phase channel flow occurs in many industrial applications, including heating and refrigeration systems. It can also occur in certain nuclear reactor accidents. For example, during a small-break loss-of-coolant accident in a pressurized water reactor, following the partial depletion of the primary coolant, condensation of steam on the primary side of the steam generator tubes can provide a heat sink for disposal of the decay heat generated in the reactor core. Condensing two-phase flow can also play an important role in the operation of the passive emergency cooling system in the advanced simplified boiling water reactor. Here, steady-state condensation in the presence of a noncondensable in a concurrent two-phase channel flow is analyzed using a two-fluid model. The effect of noncondensables on the combined heat transfer at the liquid-gas mixture interphase is accounted for by using the stagnant film model, and closure relations relevant to the ...

1995-01-01

309

Theoretical and scaling factors methods to calculate the radioactivity in operational waste streams from Unit 1 at Cernavoda NPP  

International Nuclear Information System (INIS)

The main goal of this paper is to present a methodology for calculating the radioactivity in the moderator and heat transport systems of Cernavoda NPP Unit 1, with the intention to improve the knowledge on the radionuclides inventories in the operational waste streams, and to aid the licensing process of new near surface repository. In the present paper we describe our methodology for estimating H-3 and C-14 production rates in the heavy-water moderator and heat transport systems using the capacity factors from 1997 to 2007 years. The radioactivity of the difficult-to-measure nuclides is predicted by scaling method using measured concentration in reference CANDU 6 reactor Gentilly-2. The difficult-to-measure radionuclides of primary interest in this study were those with long half-lives which have a significant role for post-closure safety assessment. The equation used to scale fission products (parents and daughters) is based on the equilibrium solution of the ...

2009-05-27

310

The prevalence, management and outcome for acute wounds identified in a wound care survey within one English health care district  

British Library Electronic Table of Contents (United Kingdom)

This paper reports the characteristics and local management of 826 acute wounds identified during an audit across all health care providers serving the population of Bradford, UK. Of the wounds encountered 303 were traumatic wounds and 237 primary closures with smaller numbers of other acute wound types. Of the 303 traumatic wounds 174 occurred in women (57.4%). Men predominated in the under 45s (65M:26F), this being largely accounted for by hand and finger trauma (n=62) particularly in patients of working age (M32:F12). Women predominated in the over 65s (50M:130F), this being largely accounted for by lower limb traumatic wounds (M24:F91), the majority of these being in patients 65 and over (M14:F82). In this sub-group of 96 patients 25 had wounds of 6 weeks or longer duration, only 3 had...

2009-01-01

311

Research on Dynamic Neutron Radiography in HANARO  

Energy Technology Data Exchange (ETDEWEB)

Neutron radiography is a non-destructive test method to examine a material by using the dependency of neutron attenuation on the nuclear characteristics of the atoms composing the object material. There are two categories of neutron radiography; static neutron radiography and dynamic neutron radiography. The static neutron radiography is a technique to observe a standing object by using a camera or a film cassette. The dynamic neutron radiography(DNR) is a technique to observe a moving object usually by using a camera. Depending on the camera frame rate, the dynamic neutron radiography is categorized into the real time neutron radiography(RTNR) and the high speed neutron radiography(HSNR). The frame rate for RTNR is 30 frames/s and that for HSNR is usually more that 500 frames/sec. Thus, RTNR is good for observing time-averaged phenomena and HSNR is good for observing instantaneous phenomena. DNR is a powerful tool for fluid visualization as well as the multi-phase flow research. This ...

2005-07-01

312

Research on Dynamic Neutron Radiography in HANARO  

International Nuclear Information System (INIS)

Neutron radiography is a non-destructive test method to examine a material by using the dependency of neutron attenuation on the nuclear characteristics of the atoms composing the object material. There are two categories of neutron radiography; static neutron radiography and dynamic neutron radiography. The static neutron radiography is a technique to observe a standing object by using a camera or a film cassette. The dynamic neutron radiography(DNR) is a technique to observe a moving object usually by using a camera. Depending on the camera frame rate, the dynamic neutron radiography is categorized into the real time neutron radiography(RTNR) and the high speed neutron radiography(HSNR). The frame rate for RTNR is 30 frames/s and that for HSNR is usually more that 500 frames/sec. Thus, RTNR is good for observing time-averaged phenomena and HSNR is good for observing instantaneous phenomena. DNR is a powerful tool for fluid visualization as well as the multi-phase flow research. This ...

2005-10-27

313

Regulatory view of the close-out of the uranium ore mine Zirovski Vrh  

International Nuclear Information System (INIS)

The production of the uranium mine Zirovski Vrh ceased in 1990. The main remaining problem of the remadiation are mine and mill tailings. The uranium mine Zirovski Vrh has one mill tailings site Borst and one waste pile Jazbec. According to the Act on protection against ionising radiation and nuclear safety which was adopted by the Parliament in 2002, they are classified as radiation facilities. Slovenian Nuclear Safety Administration (SNSA) is authorised for issuing a mandatory consent to mining work. The SNSA prepared the initial proposal of content of the safety report for the mine waste pile Jazbec. In 2005, according to the detailed content of this document, the public company Zirovski Vrh Ltd prepared the safety report which was examined by an authorised expert for radiation and nuclear safety. After a careful revision of the safety evaluation report, the consensus for mining work shall be issued by the SNSA. After finishing the mining works the SNSA shall also issue a licence ...

2005-09-05

314

Nuclear waste treatment program: Annual report for FY 1987  

Energy Technology Data Exchange (ETDEWEB)

Two of the US Department of Energy's (DOE) nuclear waste management-related goals are to ensure that waste management is not an obstacle to the further development of light-water reactors and the closure of the nuclear fuel cycle and to fulfill its institutional responsibility for providing safe storage and disposal of existing and future nuclear wastes. As part of its approach to achieving these goals, the Office of Remedial Action and Waste Technology of DOE established what is now called the Nuclear Waste Treatment Program (NWTP) at the Pacific Northwest Laboratory during the second half of FY 1982. To support DOE's attainment of its goals, the NWTP is to provide technology necessary for the design and operation of nuclear waste treatment facilities by commercial enterprises as part of a licensed waste management system and problem-specific treatment approaches, waste form and treatment process adaptations, equipment designs, and ...

1988-09-01

315

Nuclear mass prediction as an image reconstruction problem: can observed pattern determine mass values?  

Energy Technology Data Exchange (ETDEWEB)

Theoretical prediction of nuclear masses is analyzed as a pattern recognition problem on the N-Z plane. A global pattern is observed by plotting the differences between measured masses and Liquid Drop Model (LDM) predictions. After unfolding the data by removing the smooth LDM mass contributions, the remaining microscopic effects have proved difficult to model, although they display a striking pattern. These deviations carry information related to shell closures, nuc]ear deformation and the residual nuclear interactions. In the present work the more than 2000 known nuclear masses are studied as an array in the N-Z plane viewed through a mask, behind which the approximately 7000 unknown unstable nuclei that can exist between the proton and neutron drip lines are hidden. We show here that employing a Fourier transform deconvolution method these by masses can be predicted with similar accuracy than standard methods. We believe that a more general approach needs to be ...

2006-07-01

316

Nuclear mass prediction as an image reconstruction problem: can observed pattern determine mass values?  

International Nuclear Information System (INIS)

Theoretical prediction of nuclear masses is analyzed as a pattern recognition problem on the N-Z plane. A global pattern is observed by plotting the differences between measured masses and Liquid Drop Model (LDM) predictions. After unfolding the data by removing the smooth LDM mass contributions, the remaining microscopic effects have proved difficult to model, although they display a striking pattern. These deviations carry information related to shell closures, nuc]ear deformation and the residual nuclear interactions. In the present work the more than 2000 known nuclear masses are studied as an array in the N-Z plane viewed through a mask, behind which the approximately 7000 unknown unstable nuclei that can exist between the proton and neutron drip lines are hidden. We show here that employing a Fourier transform deconvolution method these by masses can be predicted with similar accuracy than standard methods. We believe that a more general approach needs to be ...

317

News from the world; Echos du monde  

Energy Technology Data Exchange (ETDEWEB)

This document gathers a series of very short articles concerning nuclear industry around the world. Areva company is investing 30 million euros in its Chalon-Saint-Marcel plant, it is the consequence of the extension of service life of nuclear power plants in the Usa. Areva holds 40% of the American market concerning the replacement of steam generators and 50% of that concerning the replacement of closure heads. The Obrigheim nuclear power plant was definitely closed down on may 2004, this decommissioning is a step forward in the German policy of progressively stepping out of nuclear energy. Chinese authorities are willing to construct 40 nuclear reactors in 15 years, despite that, the contribution of nuclear energy to the generation of electricity will reach only 4% in 2020. In 2007 Cea will begin the construction works of a new research reactor (Jules Horowitz reactor) in the Cadarache site. Prices of the yellow cake have been going up during the last years: from ...

2005-04-01

318

Mine stability evaluation of panel 1 during waste emplacement operations at WIPP  

Energy Technology Data Exchange (ETDEWEB)

The specific objectives of the work were defined by the Environmental Evaluation Group (EEG) as follows: (1) assess the stability of panel 1 during the proposed operation of waste emplacement; (2) estimate the amount of time before room closure would be expected to transfer rock loads to the waste packages. The work consisted of (1) an analysis of geotechnical data and a review of the Department of Energy`s (DOE) plans for waste emplacement in panel 1, (2) an evaluation of ground conditions based on data analysis and observations of changes in ground conditions since the first evaluation in 1993 (USBM 1993), and (3) preparation of a report and presentation of the results to EEG staff. Excluded from this study are radiological safety issues and policies. The study is based on data provided by DOE and Westinghouse Electric Corporation (operator of the site) and conversations with DOE and Westinghouse personnel. MTI cannot independently verify the accuracy of the data ...

1998-07-01

319

Integral severe accident analysis of light water nuclear power plants by IMPACT-SAMPSON code  

Energy Technology Data Exchange (ETDEWEB)

The NUclear Power Engineering Corporation (NUPEC) has developed IMPACT-SAMPSON code to analyze integral behavior of light water nuclear power plants under severe accident conditions. IMPACT-SAMPSON's distinguishing features include interconnected hierarchical modules and mechanistic models covering a wide spectrum of scenarios ranging from normal operation to severe accident events, and high-speed simulation on parallel processing computers. The integral plant behaviors of typical PWR and BWR under severe accident conditions have been analyzed with the IMPACT-SAMPSON code. The PWR plant analyzed was the three-loop, steel-dry containment type with 2,440 MWt. The AE accident scenario was supposed, that is, LOCA by 6-inch hot leg failure followed by accumulated water injection, but no ECCS and containment spray activation. The BWR plant analyzed was the 3,293 MWt BWR-5, Mark-II containment type. The TQUV accident scenario was supposed, that is, reactor scram by MSIV ...

2003-07-01

320

Incorporation of Reaction Kinetics into a Multiphase, Hydrodynamic Model of a Fischer Tropsch Slurry Bubble Column Reactor  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the development of a computational multiphase fluid dynamics (CMFD) model of the Fischer Tropsch (FT) process in a Slurry Bubble Column Reactor (SBCR). The CMFD model is fundamentally based which allows it to be applied to different industrial processes and reactor geometries. The NPHASE CMFD solver [1] is used as the robust computational platform. Results from the CMFD model include gas distribution, species concentration profiles, and local temperatures within the SBCR. This type of model can provide valuable information for process design, operations and troubleshooting of FT plants. An ensemble-averaged, turbulent, multi-fluid solution algorithm for the multiphase, reacting flow with heat transfer was employed. Mechanistic models applicable to churn turbulent flow have been developed to provide a fundamentally based closure set for the equations. In this four-field model formulation, two of the fields are used to track the gas phase (i.e., ...

2008-11-01

321

Imaging magnetic domain structure in sub-500 nm thin film elements  

Energy Technology Data Exchange (ETDEWEB)

Magnetic imaging in the transmission electron microscope (TEM) has been used to examine submicron elements with the aim of discovering down to what element size complex domain patterns can form. The elements were squares, circles, triangles, and pentagons in the size range 100{endash}500 nm and were made from 36 nm Co films or 8 nm Ni{sub 80}Fe{sub 20} (NiFe) with in-plane magnetization. The magnetic domain structures in these elements were imaged at high resolution using the differential phase contrast imaging mode in a TEM. Nonuniform magnetization structures were seen in the images. Vortices were present at remanence in all shapes of 36-nm-thick Co elements down to 100 nm size and in circular NiFe elements down to 116 nm diameter. Triangular NiFe elements did not have a vortex state at remanence, instead the magnetization curved round within the element but did not achieve complete flux closure. In simulations of square and circular NiFe elements, it was found ...

2001-06-01

322

Hydrocarbon potential of offshore South Florida basin  

Energy Technology Data Exchange (ETDEWEB)

The results of an extensive, detailed geologic and geophysical evaluation of the offshore South Florida basin show this area to have considerable hydrocarbon exploration potential. Geophysical mapping on six key horizons identified numerous structural closures at Dollar Bay through Bone Island mapping levels. Geologic evaluation indicated at least four viable potential reservoir horizons, including the Sunniland formation - the main producing unit onshore in what is called the Sunniland trend. Mature, organic rich carbonate source rocks are found in several stratigraphic intervals throughout the basin, and extensively developed seals consisting of micritic limestones and anhydrites are also common in the stratigraphic section. All the critical factors for hydrocarbon accumulation - source, reservoir, trap, and seal - appear to be present in the offshore Pulley ridge area of the South Florida basin. Using high-resolution seismic data, additional evaluation of land ...

1986-05-01

323

Groundwater quality assessment plan for single-shell tank waste management Area U at the Hanford Site  

Energy Technology Data Exchange (ETDEWEB)

Waste Management Area U (WMA U) includes the U Tank Farm, is currently regulated under RCRA interim-status regulations, and is scheduled for closure probably post-2030. Groundwater monitoring has been under an evaluation program that compared general contaminant indicator parameters from downgradient wells to background values established from upgradient wells. One of the indicator parameters, specific conductance, exceeded its background value in one downgradient well triggering a change from detection monitoring to a groundwater quality assessment program. The objective of the first phase of this assessment program is to determine whether the increased concentrations of nitrate and chromium in groundwater are from WMA U or from an upgradient source. Based on the results of the first determination, if WMA U is not the source of contamination, then the site will revert to detection monitoring. If WMA U is the source, then a second part of the groundwater quality ...

2000-03-21

324

Ground-state properties of exotic nuclei near Z=40 in the relativistic mean-field theory  

International Nuclear Information System (INIS)

Study of the ground-state properties of Kr, Sr and Zr isotopes has been performed in the framework of the relativistic mean-field (RMF) theory using the recently proposed relativistic parameter set NL-SH. It is shown that the RMF theory provides an unified and excellent description of the binding energies, isotope shifts and deformation properties of nuclei over a large range of isospin in the Z=40 region. It is observed that the RMF theory with the force NL-SH is able to describe the anomalous kinks in isotope shifts in Kr and Sr nuclei, the problem which has hitherto remained unresolved. This is in contrast with the density-dependent Skyrme-Hartree-Fock approach which does not reproduce the behaviour of the isotope shifts about shell closure. On the Zr chain we predict that the isotope shifts exhibit a trend similar to that of the Kr and Sr nuclei. The RMF theory also predicts shape coexistence in heavy Sr isotopes. Several dramatic shape transitions in the ...

325

Generalized Gas Dynamic Equations for Microflows  

CERN Document Server

n an early approach, we proposed a kinetic model with multiple translational temperature [K. Xu, H. Liu and J. Jiang, Phys. Fluids {\\bf 19}, 016101 (2007)], to simulate non-equilibrium flows. In this paper, instead of using three temperatures in $x-$, $y-$, and $z$-directions, we are going to further define the translational temperature as a second-order symmetric tensor. Based on a multiple stage BGK-type collision model and the Chapman-Enskog expansion, the corresponding macroscopic gas dynamics equations in three-dimensional space will be derived. The zeroth-order expansion gives the 10 moment closure equations of Levermore [C.D. Levermore, J. Stat. Phys {\\bf 83}, pp.1021 (1996)]. To the 1st-order expansion, the derived gas dynamic equations can be considered as a regularization of Levermore's 10 moments equations. The new gas dynamic equations have the same structure as the Navier-Stokes equations, but the stress strain relationship in the Navier-Stokes ...

2008-01-01

326

Fuzzy multi-objective decision making on a low and intermediate level waste repository safety assessment  

Energy Technology Data Exchange (ETDEWEB)

Low and intermediate waste disposal facilities safety assessment is comprised of several steps from site selection , construction and operation to post-closure performance assessment. This is a multidisciplinary and complex task , and can not be analyzed by one expert only. This high complexity can lead to ambiguity and vagueness in information and consequently in the decision making process. In order to make the decision process clear and objective, there is the need to provide the decision makers with a clear and comprehensive picture of the whole process and, at the same time, simple and easily understandable by the public. This paper suggests the development of an inference system based on fuzzy decision making methodology. Fuzzy logic tools are specially suited to deal with ambiguous data by using language expressions. This process would be capable of integrating knowledge from various fields of environmental sciences. It has an advantage of keeping record of ...

2002-07-01

327

Fuel cycle options and sustainability for new nuclear build in the UK  

International Nuclear Information System (INIS)

After a long period of stagnation in the UK, Europe and the USA, there is now a real expectation that new nuclear plants will be under construction shortly. Several factors have contributed to this change of position in the UK: the growing realisation that effective action is needed to offset greenhouse gas emissions; higher prices for fossil fuels; increasing reliance on overseas supplies of oil and gas; the limitations of wind and wave power and distribution; security of supply; the gradual realisation in the deregulated electricity generation market that nuclear power is competitive and the pending closure of most of the UK's nuclear fleet within less than 15 years. All these factors have led to a reversal of the UK Government's attitude to nuclear power, which has now ruled in favour of allowing a new generation of nuclear plants being built. This paper summarises some of the arguments that have led to this decision and the ramifications of it. In particular, ...

2008-09-14

328

Fluid dynamics analysis of a Ranque-Hilsch vortex tube  

International Nuclear Information System (INIS)

Fluid dynamic analysis of a commercial, counter-flow Ranque-Hilsch Vortex Tube (Rh vt), Ex air 25 s cfm, has been performed in this work both experimentally and numerically; in particular Rh vt cooling power and temperature separation performances have been tested in both direct cooling employment (jet impingement) and indirect cooling employment (supplying cold plates). Experimental techniques, used in this work, revealed several difficulties to produce detailed information about velocity and temperature fields inside the tube and at both the exits. Hence numerical simulation of the flow inside the tube has been conducted using the commercial Cfd code Fluent 6.3.26. Compressible, turbulent, high swirling flow inside Rh vt has been simulated by using both Rans and Les approaches. In particular several turbulence closures have been used in the Rans simulations and results have been compared with Les ones. Large Eddy Simulations have been performed using Smagorinsky ...

2008-05-01

329

Effects of morpho dynamics in shallow waters over pipeline facilities; Efeitos da morfodinamica em aguas rasas sobre instalacoes de dutos  

Energy Technology Data Exchange (ETDEWEB)

The success in developing of the oil industry operating in offshore-onshore terminals, connected by pipelines with the facilities of the coastal zone, can be attributed partially to the beach morpho dynamic monitoring. This study represents a solution to the concerns of the technical operations in coastal zones because it minimizes the impact of the petroleum production and it assures the environmental protection associated to the risks of the pipelines breaking. This impact type results mainly of the vertical and horizontal displacements of the beach, from the coastal dunes to the shore face. The mobility of the profile is associated to the magnitude of the sedimentary processes, which reproduce naturally or not, in scale of time that can vary among few days, years or decades. For the monitoring and interpretation of the beach profile mobility the following methods are recommended: calculation of the closure depth with base in the wave data; bathymetric survey ...

2003-07-01

330

Effect of drought and abscisic acid application on the osmotic adjustment of four wheat cultivars  

International Nuclear Information System (INIS)

The accumulation of osmolytes in leaf tissues and the abscisic acid-induced stomatal closure are well-recognized mechanisms associated with drought tolerance in crop plants. We determine the response in terms of osmotic potential and the contents of leaf proline, glycine betaine and soluble sugar at booting and grain filling stages of four wheat (Triticum aestivum L.) cultivars to drought and exogenously applied abscisic acid (ABA) in a pot study. Leaf sample were collected 3, 6 and 9 days after drought induction and at 48 and 72 h of re-watering (recovery). Marked decreases in osmotic potential associated with the accumulation of proline, glycine betaine and soluble sugars occurred under conditions of drought stress Accession 011320 was most sensitive to drought and showed the largest decrease in osmotic potential and least accumulation of proline, sugar and glycine betaine The inhibitory effects of drought stress were ameliorated by exogenous application of ABA. ...

2010-02-01

331

Demonstration of innovative monitoring technologies at the Savannah River Integrated Demonstration Site  

Energy Technology Data Exchange (ETDEWEB)

The Department of Energy`s Office of Technology Development initiated an Integrated Demonstration Program at the Savannah River Site in 1989. The objective of this program is to develop, demonstrate, and evaluate innovative technologies that can improve present-day environmental restoration methods. The Integrated Demonstration Program at SRS is entitled ``Cleanup of Organics in Soils and Groundwater at Non-Arid Sites.`` New technologies in the areas of drilling, characterization, monitoring, and remediation are being demonstrated and evaluated for their technical performance and cost effectiveness in comparison with baseline technologies. Present site characterization and monitoring methods are costly, time-consuming, overly invasive, and often imprecise. Better technologies are required to accurately describe the subsurface geophysical and geochemical features of a site and the nature and extent of contamination. More efficient, nonintrusive characterization and monitoring techniques ...

1993-12-31

332

Crack tip oxidation of a superalloy in molten nitrate salt  

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been proposed for use in the receiver tube panel arrays of advanced solar central receiver (SCR) designs. In this application the alloy will be exposed to a molten mixture of sodium and potassium nitrate salts at temperatures ranging up to approximately 600/sup 0/C While these salts are routinely used in a variety of applications including metal heat treating and process heat transfer, common industrial experience has been limited to maximum temperatures of 400/sup 0/C - 450/sup 0/C. There is, therefore, considerable interest in the compatibility of these salts with containment alloys at the higher temperatures associated with SCR designs. Additionally, the containment alloy may be subject to thermally induced fatigue damage resulting from intermittent cloud cover and diurnal cycling. Previous work has found that slower near-threshold fatigue crack growth rates (FCGR) in Alloy 800 result when it is tested in molten nitrate salt at 600/sup 0/C (relative to air). This ...

1983-04-01

333

Consistency of the phenomenological theories of wave-type heat transport with the hydrodynamics of a phonon gas  

International Nuclear Information System (INIS)

Various phenomenological theories of wave-type heat transport, which can be interpreted as the models of an isotropic rigid heat conductor with an internal vector state variable, have been proposed in the literature with the objective to describe the second sound propagation in dielectric crystals. The aim of this paper is to analyze the relation between these phenomenological approaches and the phonon gas hydrodynamics. The four-moment phonon gas hydrodynamics based on the maximum entropy closure of the moment equations with nonlinear isotropic phonon dispersion relation is considered for this purpose. We reformulate the equations of this hydrodynamics in terms of energy and quasi-momentum as the primitive fields and subsequently demonstrate that, from the macroscopic point of view, they can be understood as describing the reference model of an isotropic rigid heat conductor with quasi-momentum playing the role of the internal vector state variable. This model is ...

2010-09-24

334

CT appearances of unilateral cleft palate 20 years after bone graft surgery  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To describe CT appearances in patients with unilateral cleft lip and palate (CLP) 20 years after bone graft surgery. Material and Methods: Eighteen consecutive patients with unilateral CLP were examined. All patients had been treated with primary closure, both in infancy and early childhood, supplemented with bone grafting at the age of around 10 years. The CT examination of the upper jaw included a dental CT program. The CT appearances of the cleft side were compared with those of the untreated non-cleft side. Results: Abnormal CT appearances included skew nasal aperture (n=17), nasal septal deviation (n=17), low floor of nasal aperture (n=15) at or towards the cleft side, and deviation of anterior nasal spine towards the non-cleft side (n=18). The posterior part of the bone cleft was visible in all patients, and the dental arch was V-shaped in 8. Conclusion: Although adherence to the present treatment protocol is considered to give satisfactory ...

2002-11-01

335

CT appearances of unilateral cleft palate 20 years after bone graft surgery  

International Nuclear Information System (INIS)

Purpose: To describe CT appearances in patients with unilateral cleft lip and palate (CLP) 20 years after bone graft surgery. Material and Methods: Eighteen consecutive patients with unilateral CLP were examined. All patients had been treated with primary closure, both in infancy and early childhood, supplemented with bone grafting at the age of around 10 years. The CT examination of the upper jaw included a dental CT program. The CT appearances of the cleft side were compared with those of the untreated non-cleft side. Results: Abnormal CT appearances included skew nasal aperture (n=17), nasal septal deviation (n=17), low floor of nasal aperture (n=15) at or towards the cleft side, and deviation of anterior nasal spine towards the non-cleft side (n=18). The posterior part of the bone cleft was visible in all patients, and the dental arch was V-shaped in 8. Conclusion: Although adherence to the present treatment protocol is considered to give satisfactory ...

2002-11-01

336

BWR containment vessel drywell head bolt de-tensioning during noble metal chemical application  

Energy Technology Data Exchange (ETDEWEB)

Implementation of Noble Metal Chemical Application (NMCA) in a Boiling Water Reactor (BWR) requires injection of a noble metal compound while the reactor is idle at hot shutdown conditions. In order to minimize outage time, utilities are very pro-actively finding ways to reduce the number of critical path tasks. One of these tasks is to remove some containment vessel drywell head bolts during the NMCA idle time. This, thereby, saves the utilities outage time, or they can perform other tasks as desired. Using design basis conditions and state-of-the-art analytical techniques, detailed finite element stress analyses of the closure region are performed. Two acceptance criteria are evaluated. The first is that contained within Section III of the ASME Code for allowable stresses. The second relates to leak tightness, i.e., with bolt removal the joint must still remain leak tight. This paper describes the activities performed to justify bolt removal during the noble ...

2001-07-01

337

Accident impact of a spent fuel dry storage package: Analytical/experimental comparison  

Energy Technology Data Exchange (ETDEWEB)

Packages used for the storage and transportation of radioactive spent fuel must demonstrate the ability to withstand severe impact scenarios such as those established by the Atomic Energy Control Board (AECB) in Canada and the International Atomic Energy Agency (IAEA). One such package is the Dry Storage Container (DSC) for transporting and storing used fuel. The DSC model is comprised of several interactive components with materials such as high density concrete and polyurethane foam. To accurately model these materials, experimental studies were performed in order to provide material properties for the in-house finite element analysis code used. Structural assessments of the package design subject to postulated impact scenarios included a 9 meter center of gravity over corner drop, a 1 meter pin drop over the welded lid closure and a 1 meter center of gravity over lid pin drop. Simulations were carried out using full scale analytical models with validation by a ...

1996-12-31

338

A new visitor centre for CMS  

CERN Multimedia

At the inauguration of the new CMS visitor centre. The CMS experiment inaugurated a new visitor centre at its Cessy site on 14 June. This will allow the thousands of people who come to CERN each year to follow the construction of one the Laboratory's flagship experiments first-hand. CERN receives over 20,000 visitors each year. Until recently, many of them were taken on a guided tour of one of the LEP experiments. With the closure of LEP, however, trips underground are no longer possible, and the Visits' Service has put in place a number of other itineraries (Bulletin 46/2000). Since the CMS detector will be almost entirely constructed in a surface hall, it is now taking a big share of the limelight. The CMS visitor centre has been built on a platform overlooking CMS construction. It contains a set of clear descriptive posters describing the experiment, along with a video projection showing animations and movies about CMS construction. In the coming weeks, a ...

2001-01-01

339

Wear mechanism and wear prevention in coal-fueled diesel engines. Task 3, Traditional approaches to wear prevention  

Energy Technology Data Exchange (ETDEWEB)

Contamination of the lube-oil with hard abrasive particles leads to a three-body abrasive wear mechanism that highly accelerates piston ring/cylinder liner wear in coal-fueled diesel engines. One approach to reducing that wear is to modify the size and orientation of surface asperities on the cylinder to enhance the formation of a hydrodynamic film, and to provide avenues of escape for particles that would otherwise be trapped in the wear zone. Another approach is to introduce additives into the contaminated lube-oil that further enhance hydrodynamic film formation, form chemical films on the wearing surfaces, or form films on the contaminant particles. This work focuses on defining the effects of cylinder liner surface finish, various configurations of slots in the cylinder liner surface, and various additives in the contaminated lube-oil on the wear process. Wear tests were initiated in a bench apparatus using coal-ash contaminated lube-oil to test the various ...

1991-06-01

340

Wear mechanism and wear prevention in coal-fueled diesel engines  

Energy Technology Data Exchange (ETDEWEB)

Contamination of the lube-oil with hard abrasive particles leads to a three-body abrasive wear mechanism that highly accelerates piston ring/cylinder liner wear in coal-fueled diesel engines. One approach to reducing that wear is to modify the size and orientation of surface asperities on the cylinder to enhance the formation of a hydrodynamic film, and to provide avenues of escape for particles that would otherwise be trapped in the wear zone. Another approach is to introduce additives into the contaminated lube-oil that further enhance hydrodynamic film formation, form chemical films on the wearing surfaces, or form films on the contaminant particles. This work focuses on defining the effects of cylinder liner surface finish, various configurations of slots in the cylinder liner surface, and various additives in the contaminated lube-oil on the wear process. Wear tests were initiated in a bench apparatus using coal-ash contaminated lube-oil to test the various ...

1991-06-01

341

The Advanced Photon Source injection timing system  

Energy Technology Data Exchange (ETDEWEB)

The Advanced Photon Source consists of five accelerators. The injection timing system provides the signals required to cause a bunch emitted from the electron gun to navigate through intermediate accelerators to a specific bucket (1 out of 1296) within the storage ring. Two linacs and a positron accumulator ring operate at 60Hz while a booster synchrotron ramps and injects into the storage ring at 2Hz. The distributed, modular VME/VXI-based injection timing system is controlled by two EPICS-based input/output controllers (IOCs). Over 40 VME/VXI cards have been developed to implement the system. Card types range from 352MHz VXI timing modules to VME-based fiber optic fanouts and logic translators/drivers. All timing is distributed with fiber optics. Timing references are derived directly from machine low-level rf of 9.77MHz and 352MHz. The timing references provide triggers to programmable delay generators. Three grades of ...

1995-12-31

342

Studies of dynamic contact of ceramics and alloys for advanced heat engines: Final report  

Energy Technology Data Exchange (ETDEWEB)

In support of the efforts to apply ceramics in advanced heat engines, a study was made of the sliding performance of ceramics at the ring/cylinder interface of low heat rejection engines. The objective was to understand the basic mechanisms controlling the wear of candidate ceramics and thereby identify means for applying these ceramics effectively. Attempts to operate three different zirconias, silicon carbide, silicon nitride, and several plasma-sprayed ceramic coatings without lubrication were unsuccessful because of high friction and high wear rates. Experiments using a polyalphaolefin lubricant at temperatures to 260 C identified several combinations having wear rates in the general range likely to be acceptable for engines. Plasma-sprayed coatings of chromium oxide and hypersonic powder flame sprayed coatings of cobalt-bonded tungsten carbide performed particularly well as ring coatings. Similar performance was obtained with these ...

1988-03-01

343

Steroidal hydrocarbons of the Kishenehn Formation, northwest Montana  

Energy Technology Data Exchange (ETDEWEB)

The Oligocene Kishenehn Formation of northwest Montana and southeast British Columbia consists of fluvial and lacustrine sediments (marlstones, lignites and oil shales) deposited in an elongate, intermontane half-graben. The petroleum source rock potential and steroidal hydrocarbon distribution of selected shales of the Kishenehn Formation were examined. Several steroidal hydrocarbon series were documented, including 4-desmethylsteranes, 4-methylsteranes, sterenes, diasterenes, spirosterenes, C-ring monoaromatic steroids and B-ring monoaromatic anthrasteroids. Non-steroid hydrocarbons present include hopenes, ..beta beta..-hopanes, moretanes, perylene, botryococcane, a series of alkylcyclohexanes, and a fused-ring aromatic tentatively identified as a tetrahydrochrysene. Source rock analysis indicates that the Kishenehn Formation possesses excellent petroleum source potential. Conventional thermal maturity parameters, as ...

1987-01-01

344

Prostaglandin (PG) E3 synthesis elicted by adrenergic stimuli in guinea-pig trachea (GPT) is mediated primarily by B2 adrenergic receptors  

Science.gov (United States)

The purpose of this study was to examine arachidonic acid (AA) metabolism and to characterize the type of adrenergic receptor (AR) involved in the production of the major metabolite of this fatty acid. ({sup 14}C)AA was incubated with GPT-rings and the radiolabelled products were extracted and separated by TLC method. The medium was also assayed for radiolabelled immunoreactive PG's (iPG's) and leukotrienes (LT) B4 and C4 by RIA or Enzyme immunoassay (EIA) after exposure to various AR agonists. ({sup 14}C)AA was incorporated into GPT-rings and metabolized mainly into iPGE2 and smaller amounts into PGF2{alpha}. Trace amounts of PGD2 and 6-keto-PGF1{alpha} but not LTB4 or LTC4 were detected by RIA and/or EIA. Incubation of GPT rings for 15 minutes with isoproterenol and salbutamol resulted in a significant increase of PGE2 synthesis (optimum conc: 10{sup {minus}7}, 10{sup {minus}7}M respectively). In ...

1990-02-26

345

Prostaglandin (PG) E3 synthesis elicted by adrenergic stimuli in guinea-pig trachea (GPT) is mediated primarily by B2 adrenergic receptors  

International Nuclear Information System (INIS)

The purpose of this study was to examine arachidonic acid (AA) metabolism and to characterize the type of adrenergic receptor (AR) involved in the production of the major metabolite of this fatty acid. ["1"4C]AA was incubated with GPT-rings and the radiolabelled products were extracted and separated by TLC method. The medium was also assayed for radiolabelled immunoreactive PG's (iPG's) and leukotrienes (LT) B4 and C4 by RIA or Enzyme immunoassay (EIA) after exposure to various AR agonists. ["1"4C]AA was incorporated into GPT-rings and metabolized mainly into iPGE2 and smaller amounts into PGF2#alpha#. Trace amounts of PGD2 and 6-keto-PGF1#alpha# but not LTB4 or LTC4 were detected by RIA and/or EIA. Incubation of GPT rings for 15 minutes with isoproterenol and salbutamol resulted in a significant increase of PGE2 synthesis (optimum conc: 10"-"7, 10"-"7M respectively). In contrast, dobutamine, norepinephrine, phenylnephrine ...

1991-04-21

346

Basic study of entire whole-body PET scanners based on the OpenPET geometry  

International Nuclear Information System (INIS)

A conventional PET scanner has a 15-25 cm axial field-of-view (FOV) and images a whole body using about six bed positions. An OpenPET geometry can extend the axial FOV with a limited number of detectors. The entire whole-body PET scanner must be able to process a large amount of data effectively. In this work, we study feasibility of the fully 3D entire whole-body PET scanner using the GATE simulation. The OpenPET has 12 block detector rings with the ring diameter of 840 mm and each block detector ring consists of 48 depth-of-interaction (DOI) detectors. The OpenPET has the axial length of 895.95 mm with five parts of 58.95 mm open gaps. The OpenPET has higher single data loss than a conventional PET scanner at grouping circuits. NECR of the OpenPET decreases by single data loss. But single data loss is mitigated by separating the axially arranged detector into two parts. Also, multiple coincidences are found to be ...

2010-09-01

347

Corrective Action Decision Document/Closure Report for Corrective Action Unit 409: Other Waste Sites, Tonopah Test Range, Nevada (Rev. No.: 0, June 2001)  

Energy Technology Data Exchange (ETDEWEB)

This Corrective Action Decision Document/Closure Report (CADD/CR) has been prepared for Corrective Action Unit (CAU) 409: Other Waste Sites, Tonopah Test Range (TTR), Nevada, in accordance with the Federal Facility Agreement and Consent Order. Located near Area 3 on the TTR approximately 140 miles northwest of Las Vegas, Nevada, CAU 409 is comprised of three Corrective Action Sites (CASs): CAS RG-24-001-RGCR, Battery Dump Site; CAS TA-53-001-TAB2, Septic Sludge Disposal Pit (referred to as Septic Sludge Disposal Pit No.1); CAS TA-53-002-TAB2, Septic Sludge Disposal Pit (referred to as Septic Sludge Disposal Pit No.2). This CADD/CR identifies and rationalizes the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Operations Office's (NNSA/NV's) recommendation that no corrective action is deemed necessary for CAU 409. The CADD/CR have been combined into one report based on sample data collected during the field ...

2001-06-12

348

Comprehensive Approaches to Multiphase Flows in Geophysics - Application to nonisothermal, nonhomogenous, unsteady, large-scale, turbulent dusty clouds I. Hydrodynamic and Thermodynamic RANS and LES Models  

Energy Technology Data Exchange (ETDEWEB)

The objective of this manuscript is to fully derive a geophysical multiphase model able to ''accommodate'' different multiphase turbulence approaches; viz., the Reynolds Averaged Navier-Stokes (RANS), the Large Eddy Simulation (LES), or hybrid RANSLES. This manuscript is the first part of a larger geophysical multiphase project--lead by LANL--that aims to develop comprehensive modeling tools for large-scale, atmospheric, transient-buoyancy dusty jets and plume (e.g., plinian clouds, nuclear ''mushrooms'', ''supercell'' forest fire plumes) and for boundary-dominated geophysical multiphase gravity currents (e.g., dusty surges, diluted pyroclastic flows, dusty gravity currents in street canyons). LES is a partially deterministic approach constructed on either a spatial- or a temporal-separation between the large and small scales of the flow, whereas RANS is an entirely probabilistic ...

2005-09-05

349

Wear and friction coefficient of particle reinforced Ti-alloys  

Energy Technology Data Exchange (ETDEWEB)

Particulate Reinforced Titanium matrix composites (PRTi) exhibit some improved specific mechanical properties in comparison with those of unreinforced titanium alloys as a result of the combination of the high strength and stiffness of ceramic particles with the toughness and damage tolerance provided by the metal matrix. The poor tribological properties of the titanium exclude titanium alloys from applications where wear resistance is required (brakes, rotating parts, sliding parts). The addition of ceramic particles improves the tribological properties of metals sensitive to adhesive and /or abrasive wear significantly. In this work, the wear resistance and the friction coefficient of Ti6Al-6V-2Sn reinforced with TiC particles and Ti6Al-4V reinforced with SiC particles (prototype material) are compared with the unreinforced alloys. Pin on disc and pin on ring tests were carried out against standard steel (100Cr6) as a function of pressure, speed and temperature. ...

2004-11-01

350

Interrelation between grain boundary characteristics and intergranular stress corrosion cracking of thermally treated alloy 690 and shot peened alloy 800 in high temperature acidic and alkaline solution  

Energy Technology Data Exchange (ETDEWEB)

To clarify the acidic and alkaline Intergranular Stress Corrosion Cracking (IGSCC) mechanism of thermally treated alloy 690 (alloy 690 TT) and shot peened alloy 800 (alloy 800 SP), C-ring tests were conducted in deaerated HCl solutions and in deaerated NaOH solutions at 350degC, compared with the acidic and the alkaline IGSCC susceptibilities of mill-annealed alloy 600 (alloy 600 MA), full-sensitized one (alloy 600 FS) and thermally treated one (alloy 600 TT). Grain boundary characteristics, such as chromium depleted zone and chromium carbide precipitation, were examined using modified Huey test and Transmission Electron Microscopy. Potential-pH diagram for Ni, Cr, Fe-H{sub 2}O system at 350degC was constructed and the solubilities of NiO, Cr{sub 2}O{sub 3} and Fe{sub 3}O{sub 4} were also calculated to evaluate the stability of oxide films which were formed on the surfaces of alloy 690, 800 and 600. Under the acidic condition, the IGSCC susceptibility of alloy 800 ...

2001-05-01

351

Interrelation between grain boundary characteristics and intergranular stress corrosion cracking of thermally treated alloy 690 and shot peened alloy 800 in high temperature acidic and alkaline solution  

International Nuclear Information System (INIS)

To clarify the acidic and alkaline Intergranular Stress Corrosion Cracking (IGSCC) mechanism of thermally treated alloy 690 (alloy 690 TT) and shot peened alloy 800 (alloy 800 SP), C-ring tests were conducted in deaerated HCl solutions and in deaerated NaOH solutions at 350degC, compared with the acidic and the alkaline IGSCC susceptibilities of mill-annealed alloy 600 (alloy 600 MA), full-sensitized one (alloy 600 FS) and thermally treated one (alloy 600 TT). Grain boundary characteristics, such as chromium depleted zone and chromium carbide precipitation, were examined using modified Huey test and Transmission Electron Microscopy. Potential-pH diagram for Ni, Cr, Fe-H_2O system at 350degC was constructed and the solubilities of NiO, Cr_2O_3 and Fe_3O_4 were also calculated to evaluate the stability of oxide films which were formed on the surfaces of alloy 690, 800 and 600. Under the acidic condition, the IGSCC susceptibility of alloy 800 SP was high. The ...

2001-05-01

352

XENON-POISONING COMPUTER  

Science.gov (United States)

A computer was built for use with the NRU reactor to solve the problem of Xe/sup 135/ concentrations. The effect of any changes in reactor on Xe/sup 135/ concentration can be predicted and steps taken to avoid poisoning out. An electromechanical system was used for the computer to avoid the inherent disadvantages that electronic analog computers present for problems of very long solution times. The electromechanical analog computer has a high order of reliability and contains no vaccum tubes, commutators, slip rings, relays, or aluminum electrolytic capacitors. It is insensitive to transient disturbarce. In the event of failure of components or interruption of line voltage, it will retain existing information. The computer was designed for ~ 1% accuracy in Xe/ sup 135/ concentration readings. (W.D.M.)

1958-05-01

353

Wear modes active in angular contact ball bearings operating in liquid oxygen environment of the Space Shuttle turbopumps  

Energy Technology Data Exchange (ETDEWEB)

Extensive experimental investigation has been carried out on used flight bearings of the high pressure oxidizer turbopumps (HPOTP) of the space shuttle main engine (SSME) in order to determine the dominant wear modes, their extent, and causes. The paper presents the methodology, various surface analysis techniques used, results, and discussion. The mode largely responsible for premature bearing wear has been identified as adhesive/shear peeling of the upper layers of bearing balls and rings. This mode relies upon the mechanisms of scale formation, breakdown, and removal, all of which are greatly enhanced by the heavy oxidation environment of the HPOTP. Major causes of the high wear rates appear to be lubrication and cooling, both inadequate for the imposed conditions of operation. Numerous illustrations and evidence are provided. 22 refs.

1993-04-01

354

Transmission electron microscopy of undermined passive films on stainless steel  

Energy Technology Data Exchange (ETDEWEB)

A study has been made of the passive film remaining over pits on stainless steel using a high resolution transmission electron microscope. Type 305 stainless steel was passivated in a borate buffer solution and pitted in ferric chloride. Passive films formed at 0.2 V relative to a saturated calomel electrode were found to be amorphous. Films formed at higher potentials showed only broad diffraction rings. The passive film was found to cover a remnant lacy structure formed over pits passivated at 0.8 V. The metallic strands of the lace were roughly hemitubular in shape with the curved surface facing the center of the pit.

1999-06-01

355

Total synthesis of solanoeclepin A  

British Library Electronic Table of Contents (United Kingdom)

Cyst nematodes are troublesome parasites that live on, and destroy, a range of important host vegetable plants. Damage caused by the potato cyst nematode has now been reported in over 50 countries. One approach to eliminating the problem is to stimulate early hatching of the nematodes, but key hatching stimuli are not naturally available in sufficient quantities to do so. Here, we report the first chemical synthesis of solanoeclepin A, the key hatch-stimulating substance for potato cyst nematode. The crucial steps in our synthesis are an intramolecular cyclization reaction for construction of the highly strained tricyclo[5.2.1.01,6]decane skeleton (DEF ring system) and an intramolecular Diels???Alder reaction of a furan derivative for the synthesis of the ABC carbon framework. The present ...

2011-01-01

356

The minimal series of N=1 and N=2 superconformal topological field theory  

International Nuclear Information System (INIS)

We obtain conformal invariant topological field theories with N = 2 supersymmetry by twisting Sevrin, Troost and Van Proeyen's SU(2) x SU(2) x U(1) extended N = 4 superconformal field theories. We expect that the number of physical states is finite although the original N = 4 theories have continuous spectra. It is shown that the number of physical states is actually finite when the central charge c < 6 in the corresponding N = 4 theories. The physical states inherit the structure of the chiral ring in N = 2 superconformal minimal series which is obtained by the reduction from N = 4 theories. We also show that the algebra contains the topological N = 4 superconformal algebra as subalgebra. Therefore a closed set of a finite number of physical states in the topological N = 1 superconformal algebra can also be obtained. (orig.).

1991-06-01

357

The liquefaction of clayey soils under cyclic loading  

British Library Electronic Table of Contents (United Kingdom)

This paper seeks to investigate the liquefaction of clayey soils, a phenomenon that has been the trigger for many natural disasters in the last few decades, including landslides. Research was conducted on artificial clay?sand mixtures and natural clayey soils collected from the sliding surfaces of earthquake-induced landslides. The undrained response of normally consolidated clayey soils to cyclic loading was studied by means of a ring-shear apparatus. For the artificial clay?sand mixtures, it was found that the presence of a small amount of bentonite (?7%) would cause rapid liquefaction, while a further increase in bentonite content (?11%) produced the opposite effect of raising soil resistance to liquefaction by a significant degree. It was demonstrated that the bentonite?sand mixture wa...

2006-01-01

358

Synthetic enantiopure aziridinomitosenes: preparation, reactivity, and DNA alkylation studies.  

Science.gov (United States)

An enantiocontrolled route to aziridinomitosenes had been developed from l-serine methyl ester hydrochloride. The tetracyclic target ring system was assembled by an internal azomethine ylide cycloaddition reaction based on silver ion-assisted intramolecular oxazole alkylation and cyanide-induced ylide generation via a labile oxazoline intermediate (62 to 66). Other key steps include reductive detritylation of 26, methylation of the N-H aziridine 56, oxidation of the sensitive cyclohexenedione 68 to quinone 70, and carbamoylation using Fmoc-NCO. Although the aziridinomitosene tetracycle is sensitive, a range of protecting group manipulations and redox chemistry can be performed if suitable precautions are taken. A study of DNA alkylation by the first C-6,C-7-unsubstituted aziridinomitosene 11a has been carried out, and evidence for DNA cross-link formation involving nucleophilic addition to the quinone subunit is described. PMID:14677970

2003-12-24

359

Spin transition in octahedral metal complexes containing tetraazamacrocyclic ligands  

British Library Electronic Table of Contents (United Kingdom)

This review focusses on spin crossover complexes with octahedral metal ions which are bound to a tetraazamacrocyclic ligand and additionally either to two monodentate ligands or to one bidentate ligand. Macrocyclic ligands with a sufficiently large ring size prefer to coordinate to metal ions in an equatorial fashion yielding trans-octahedral coordination environments. In contrast, twelve-membered tetraazamacrocycles with high steric rigidity, such as 2,11-diaza[3.3](2,6)pyridinophanes or 2,11-dithia[3.3](2,6)pyridinophane, are prone to form cis-octahedral complexes. While the electronic and the steric properties of the coordinated tetraazamacrocycle in trans-octahedral complexes are very likely responsible for the paucity of observed spin transitions, the cis-octahedral coordination mode ...

2009-01-01

360

Solar energy modulator  

Energy Technology Data Exchange (ETDEWEB)

A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror thereby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.

1981-07-01

361

Simulation study of feedback systems based on a two-tap FIR filter. Under beam-beam collisions  

Energy Technology Data Exchange (ETDEWEB)

The performance of bunch-feedback systems based on two-tap FIR filters is discussed, particularly for transverse cases. Since they are the simplest type of FIR digital filters, the two-tap FIR filters should be suited to systems that require a very fast processing speed. However, in these feedback systems, a bunch must turn along a ring several times from the position-measurement to feedback kicking. Within these turns, irregular phase-jumps in the betatron motion can occur, due to several causes, such as the wake forces and beam-beam force. The discussion given in this paper is focussed on the effect of beam-beam collisions on these feedback systems. Based on linear theory and simulation studies, it has been found that these feedback systems can work with good performance, even under the influence of a strong beam-beam force. (author)

1998-04-01

362

Simulation on Impact of Information Guidance on Regional Traffic Flow  

British Library Electronic Table of Contents (United Kingdom)

The traffic flow information guidance can improve the operating efficiency of regional traffic. On the basis of the information guidance model and survey data, this paper takes advantage of the VISSIM software to simulate the traffic in a region within the Southwest Second Ring of Beijing constructed by six roads and six intersections and makes a comparative evaluation on the operation of the regional road traffic flow before and after the implementation of the traffic flow information guidance measures. The analysis of five different guided flow cases shows that if the guided left-turn traffic flows in southbound I.A increases from 10% to 30%, the travel time of the left-turn traffic flow in southbound I.A has a reduction from 18% to 42%, and its delay also reduces from 234 s to 164 s. In...

2008-01-01

363

Selected topics in particle accelerators: Proceedings of the CAP meetings. Volume 5  

Energy Technology Data Exchange (ETDEWEB)

This Report includes copies of transparencies and notes from the presentations made at the Center for Accelerator Physics at Brookhaven National Laboratory Editing and changes to the authors` contributions in this Report were made only to fulfill the publication requirements. This volume includes notes and transparencies on nine presentations: ``The Energy Exchange and Efficiency Consideration in Klystrons``, ``Some Properties of Microwave RF Sources for Future Colliders + Overview of Microwave Generation Activity at the University of Maryland``, ``Field Quality Improvements in Superconducting Magnets for RHIC``, ``Hadronic B-Physics``, ``Spiking Pulses from Free Electron Lasers: Observations and Computational Models``, ``Crystalline Beams in Circular Accelerators``, ``Accumulator Ring for AGS & Recent AGS Performance``, ``RHIC Project Machine Status``, and ``Gamma-Gamma Colliders.``

1995-10-01

364

Secondary electron yield measurements from thin surface coatings for NLC electron cloud reduction  

CERN Document Server

In the beam pipe of the positron damping ring of the Next Linear Collider, electrons will be created by beam interaction with the surrounding vacuum chamber wall and give rise to an electron cloud. Several solutions are possible for avoiding the electron cloud, without changing the bunch structure or the diameter of the vacuum chamber. Some of the currently available solutions for preventing this spurious electron load include reducing residual gas ionization by the beam, minimizing beam photon-induced electron production, and lowering the secondary electron yield (SEY) of the chamber wall. We will report on recent SEY measurements performed at SLAC on TiN coatings and TiZrV non-evaporable getter thin films.

2004-01-01

365

Scuffing behavior of gray iron and 1080 steel in reciprocating and rotational sliding  

British Library Electronic Table of Contents (United Kingdom)

Scuffing damage is catastrophic and typically not self-healing. It severely affects the life and reliability of engineering components, such as cams, roller bearings, piston rings, cylinder bores and gears. Gray iron and 1080 steel are important materials for these extremely demanding structural components. There have been several scuffing studies done in the past with various types of steel and cast iron. However, in these studies there was no attempt to compare the scuffing resistance of cast iron and steel materials with similar matrices. In the present study, scuffing tests were performed with the matrices of gray iron and 1080 steel being fully pearlitic. This allows for a direct evaluation of the effect of the graphite flakes on scuffing resistance. The scuffing behavior for these ma...

2011-01-01

366

Retention of ring structure in cyclopentane and alkylcyclopentane molecular cations  

Energy Technology Data Exchange (ETDEWEB)

All measurements were made with the NBS high-pressure photoionization mass spectrometer. The fractional of C/sub 5/H/sub 10//sup +/ions in a cyclopentane-cyclohexane mixture were determined as a function of pressure in order to define the fraction of the ions which did charge exchange with cyclohexane; i.e. the fraction which remained cyclic after ionization. The data for mixtures of various compositions (2.5 to 10% cyclohexane) are summarized for measurements performed at 10.62 eV: (a) 292K, > 96% cyclic; 347 K, greater than or equal to 94% cyclic; 386 K, 84 +- 4% cyclic; and 412 K, 78 +- 6% cyclic; entropy, enthalpy, and activation energy were determined; 10.49 eV was obtained as the ionization potential of cyclopentane. 1 figure.

1980-01-01

367

Resonance Raman and photophysical studies of transition metal complexes in solution and entrapped in zeolites  

Science.gov (United States)

We have obtained convincing evidence for localization of the optical electron on a single-ring fragment of a chelated bipyridine-like'' ligand (ie., pyridylpyrazine or 4-Methyl-bipyridine). In addition we have completed studies of Ru(bipyrazine){sub 3}{sup 2+} in aqueous sulfuric acid (0--98% by weight) and find clear evidence for sequential addition of six-protons to the six peripheral nitrogen atoms. Studies of zeolite-entrapped complexes are continuing and a series of homo- and heteroleptic complexes have been prepared and characterized. Finally, the synthesis of zeolite-entrapped metallophthalocyanines has now been developed and the copper and cobalt analogues synthesized. The characterization of these materials is now in progress.

1992-03-31

368

Recycler model magnet test on temperature compensation for strontium ferrite  

Energy Technology Data Exchange (ETDEWEB)

The Recycler ring magnet will be made of Strontium ferrite permanent magnets. A strontium ferrite permanent magnet without compensation has a temperature coefficient of -0.2 % in dB/dT. To compensate this effect, we are utilizing 30 % Ni 70 % Fe alloy, a temperature compensation ferromagnetic material with a low Curie point. To search for optimum commercially available material and optimum condition, we made a couple of simple model magnets, and tested with several different compensating material. The test results are reported and its optimal conditions are shown. Several different configurations were tested including a possible 2 kG magnet configuration.

1995-10-01

369

Photodegradation of flupentixol in aqueous solution under irradiation at 254nm: Identification of the photoproducts generated  

British Library Electronic Table of Contents (United Kingdom)

After irradiation at 254nm of aqueous solutions of the antipsychotic drug flupentixol, the structures of the photodegradation products were determined by ultra high performance liquid-chromatography linked to mass spectrometry. Fragmentation patterns of the parent ions were established on a hybrid linear ion trap-orbitrap mass spectrometer allowing accurate mass measurements of both parent and daughter ions. This allowed to propose plausible structures for the main photolysis products of flupentixol. A total of nine photoproducts were detected after irradiation of the drug. The main photoproduct is generated following the addition of a hydroxyl group on the double bond adjacent to the thioxanthene ring. Secondary photoproducts were also observed.

2010-01-01

370

New advances and applications in pulsed-plasma nitriding of gear and power train systems; Neue Erkenntnisse und Anwendungen der Puls-Plasma-Nitriertechnik im Bereich Getriebe- und Antriebstechnik  

Energy Technology Data Exchange (ETDEWEB)

Due to size and costs of big slewing rings, the common methods of experimental trial and error together with destructive test methods for verification of the inductive hardening process are limited. Thereby it is essential to simulate the hardening process in addition to the tests. With these simulations, it should be possible to get conclusions for the hardening pattern, the residual stress and distortion. With actually existing methods a fully three dimensional simulation is extremely time consuming. For that reason, a new method was developed that combines two dimensional with three dimensional simulation to shorten the time for calculation tremendously. (orig.)

2010-09-15

371

Muon physics with the proposed Pulsed Lepton Source at LAMPF  

Energy Technology Data Exchange (ETDEWEB)

The Pulsed Lepton Source (PLS) project opens some exciting possibilities for muon and neutrino physics . The PLS would use the 0.25 4s proton pulses from the upgraded Proton Storage Ring (PSR) at LAMPF to create short, intense bursts of muons and neutrinos. The neutrino beam would be used for a few fundamentally important weak interaction physics experiments. The muon beams would find a wide variety of applications in both fundamental and applied'' muon physics areas. After a brief discussion of the physical layouts of the PSR and the proposed PLS in Sec. 2 and muon area in Sec. 3, we note some of the muon physics experiments and areas that could advantageously be addressed at the PLS in Secs. 4 and 5, and conclude in Sec. 6.

1992-01-01

372

Mismatch measurement and correction tools for the PS-SPS transfer of the 26GeV/C LHC beam  

CERN Document Server

TRANSVERSE EMITTANCE PRESERVATION IS A MAJOR CONCERN OF THE LHC INJECTOR CHAIN. MINIMISATION OF THE BLOW-UP DUE TO MISMATCH AT INJECTION INTO THE SPS IS THEREFORE MANDATORY. WHILE THE TRANSVERSE POSITIONN OF THE BEAM IN THE SPS INJECTION LINE IS MONITORED BUNCH BY BUNCH BY AN OTR (OPTICAL TRANSITION RADIATION) SCREEN AND A FAST CCD (CHARGED COUPLED DEVICE) CAMERA, THE PHASE SPACE MATCHING AT INJECTION IS MONITORED BY AN OTR BASED MISMATCH MONITOR IN THE SPS RING. ORTHOGONAL TUNING KNOBS WERE DEVELOPED TO TUNE INDEPENDENTLY TWISS PARAMETERS, DISPERSION AND DISPERSION DERIVATIVE. IN THIS PAPER WE DESCRIBE THE MISMATCH CORRECTION MECHANISM AS WELL AS THE TWO MONITORING SYSTEMS. WE REPORT ON FIRST MEASUREMENTS WHICH WERE CARRIED OUT DURING THE 1998 SPS RUN.

1999-01-01

373

Minimal Neutrino Beta Beam for Large theta_13  

CERN Document Server

We discuss the minimum requirements for a neutrino beta beam if theta_13 is discovered by an upcoming reactor experiment, such as Double Chooz or Daya Bay. We require that both neutrino mass hierarchy and leptonic CP violation can be measured to competitive precisions with a single-baseline experiment in the entire remaining theta_13 range. We find that for very high isotope production rates, such as they might be possible using a production ring, a (B,Li) beta beam with a gamma as low as 60 could already be sufficient to perform all of these measurements. If only the often used nominal source luminosities can be achieved, for example, a (Ne,He) beta beam from Fermilab to a possibly existing water Cherenkov detector at Homestake with gamma \\sim 190-350 (depending on the Double Chooz best-fit) could outperform practically any other beam technology including wide-band beam and neutrino factory.

2008-01-01

374

Mechanism of filler action in reducing the wear of PTFE polymer by differential scanning calorimetry  

British Library Electronic Table of Contents (United Kingdom)

Two types of representative nanometer materials, i.e., fibroid nanometer attapulgite and approximate spherical ultrafine diamond, were selected as fillers of polytetrafluoroethylene (PTFE) to study the mechanism of the wear-reducing actions of the fillers in PTFE composites. The friction and wear tests were performed on a block-on-ring wear tester under dry sliding conditions. Differential scanning calorimetry (DSC) was used to investigate material microstructure and to examine modes of failure. No significant change in coefficient of friction was found, but the wear rate of PTFE composites was orders of magnitude less than that of pure PTFE. DSC analysis revealed that nanometer attapulgite and ultrafine diamond played a heterogeneous nucleation role in PTFE matrix and consequently resulte...

2007-01-01

375

Linac automated beam phase control system.  

Energy Technology Data Exchange (ETDEWEB)

Adjustment of the rf phase in a linear accelerator is crucial for maintaining optimal performance. If phasing is incorrect, the beam will in general have an energy error and increased energy spread. While an energy error can be readily detected and corrected using position readings from beam position monitors at dispersion locations, this is not helpful for correcting energy spread in a system with many possible phase errors. Uncorrected energy spread results in poor capture efficiency in downstream accelerators, such as the Advanced Photon Source's (APS's) particle accumulator ring (PAR) or booster synchrotron. To address this issue, APS has implemented beam-to-rf phase detectors in the linac, along with software for automatic correction of phase errors. We discuss the design, implementation, and performance of these detectors and how they improved APS top-up operations.

2006-01-01

376

Ionized gas and radio emission in the barred Seyfert galaxy NGC 5728  

International Nuclear Information System (INIS)

This paper reports extensive new optical and radio observations of NGC 5728, emphasizing the central regions. Deep photographs revealing detail in the faint spiral arms are briefly discussed. Broad-band UBV CCD images obtained to examine the colors of the stellar populations that comprise the bar and central ring are presented. The velocity field and emission maps obtained from imaging spectroscopic measurements in the H-alpha emission line are discussed. Conventional long-slit spectra covering the ionized gas in the nuclear region are described. Detailed maps of the radio emission in the central regions of NGC 5728 are presented. These combined data provide considerable evidence for the inflow of gas into the nuclear region, in response to the nonaxisymmetric gravitational potential of the bar. The possible relation of this phenomenon to the Seyfert nature of NGC 5728 is also considered. 48 references.

377

Investigation of the removal efficiency of gasborne particles in a scrubber column  

Energy Technology Data Exchange (ETDEWEB)

Tests on the scrubbing column have led to the following results: Use of a scrubbing column with Raschig rings is only meaningful for the sedimentation of particles exceeding diameters of 0.5 ..mu..m; drops of diameter size 1.5 ..mu..m are formed in the column; more efficient drop precipitators in the column air flow ease the load on subsequent suspended material filters thereby contributing to a longer life of these filters even at higher sodium ion concentrations in the washing water; with distillate of an 8% rather than 0.8% salt solution a decontamination factor greater than 10 can be calculated since larger particles precipitate more readily. This only applies, however, under the condition that the washing water is renewed regularly, if necessary daily where higher aerosol concentrations are present. If not, the decontamination factor will be reduced through the salt-containing secondary aerosols from the washing water.

1983-01-01

378

Investigation of the removal efficiency of gasborne particles in a scrubber column  

International Nuclear Information System (INIS)

Tests on the scrubbing column have led to the following results: Use of a scrubbing column with Raschig rings is only meaningful for the sedimentation of particles exceeding diameters of 0.5 #mu#m; drops of diameter size 1.5 #mu#m are formed in the column; more efficient drop precipitators in the column air flow ease the load on subsequent suspended material filters thereby contributing to a longer life of these filters even at higher sodium ion concentrations in the washing water; with distillate of an 8% rather than 0.8% salt solution a decontamination factor greater than 10 can be calculated since larger particles precipitate more readily. This only applies, however, under the condition that the washing water is renewed regularly, if necessary daily where higher aerosol concentrations are present. If not, the decontamination factor will be reduced through the salt-containing secondary aerosols from the washing water. (orig.).

379

Investigation of Tumor-Peritoneal Interactions in the Pathogenesis of Peritoneal Metastases using a Novel Ex Vivo Peritoneal Model1  

British Library Electronic Table of Contents (United Kingdom)

BackgroundPeritoneal metastasis occurs in up to 30% of patients with gastric cancer. The aim of this experimental study is to develop and validate a novel ex vivo model of the human peritoneum to better identify factors involved in the development of peritoneal metastasis in order to improve its management and prognosis. MethodsPeritoneal discs harvested from hernia sacs obtained at inguinal hernia surgery were suspended in media using Teflon rings. Viability of the tissue was investigated using MTS assay, light and scanning electron microscopy (LM and SEM) over 72 h. To assess validity of the model, phenotypic changes in tumor cells were investigated. Changes in matrix metalloproteinases (MMP)-2 and -9 activities in HGC and AGS gastric adenocarcinoma cells after co-culture were investigat...

2010-01-01

380

Innovating methodologies brought into operation by Framatome for the Phenix control; Methodologies innovatrices mises en oeuvre par Framatome pour le controle de Phenix  

Energy Technology Data Exchange (ETDEWEB)

The renovation programme of the Phenix nuclear power plant (fast neutrons reactor situated at Marcoule) has for objective to ensure the reactor operation lengthening. In this frame, expertise and monitoring operation in situ of materials have been started. The presence of sodium and a temperature at the cold breakdown of the primary circuit between 150 and 180 degrees (Celsius) imply, for fast reactors, very special conditions. In this context, Framatome has realised three intervening in the area of nondestructive testing: the inspection of the cone-shaped support ring, the monitoring of the upper part of the primary vessel and the monitoring of the intermediary exchanger equipment. (N.C.)

2000-06-01

381

Hydrogen-atom attack on methyl viologen in aqueous solution studied by pulse radiolysis  

International Nuclear Information System (INIS)

Using hydrogen at high pressures of up to 150 bar as an OH scavenger in aqueous MV"2"+ solutions (pH 1) it is possible to differentiate between two kinds of transient formed simultaneously by H-atom attack on methyl viologen. One of them is assigned to an H adduct on the N atom, MV"+H"+, with absorption bands identical to those of the radical cation, MV"+. The MV"+H"+ species deprotonates forming the long-lived radical cation, MV"+. The second type of transient produced is attributed to an H-adduct on the ring carbon, MV"2"+H, decaying by second-order kinetics. The formation of MV"+ by electron transfer from the propan-2-ol radical has been reinvestigated (pH 0 to 7); its absorption spectrum does not change in this pH range. Rate constants and molar extinction coefficients are presented. (U.K.).

1984-01-01

382

High-tension corona controlled ozone generator for environment protection  

International Nuclear Information System (INIS)

Engineering details of a high voltage driven corona-plasma ozone generator are described. The plasma diode of generator has coaxial cylindrical geometry with cathode located inside anode. Cathode is made of a large number of radial gas nozzles arranged on central tubular mast which admits oxygen gas. The sharp endings of the nozzles along with a set of corona rings create the high electric field at the cathode required for formation of dense corona plume responsible for O_3 evolution. A model of coronal plasma generation and ozone production is presented. The plasma formation is strongly dependent on the electric field and temperature in side diode where a high electron density in a low temperature negative corona is suited for high ozone yields. These are established by suitable regulation of A-K gap, voltage, oxygen pressure, and cathode-nozzle population.

2010-02-01

383

High-Resolution Optical Coherence Tomography Findings in Solar Maculopathy and the Differential Diagnosis of Outer Retinal Holes  

British Library Electronic Table of Contents (United Kingdom)

PurposeTo characterize the morphology of outer retinal holes caused by solar maculopathy, using spectral-domain optical coherence tomography (SD-OCT). DesignThis study is an observational case series. MethodsThe SD-OCT findings of 3 patients (6 eyes) with chronic solar maculopathy are presented. ResultsSD-OCT demonstrates a characteristic appearance of partial-thickness hole(s) in the outer retina at the fovea. In 3 of 6 eyes, there is 1 hole directly beneath the umbo. In the remaining 3 eyes, there are multifocal holes spread across the fovea. Holes in more restricted layers, as had been previously reported with time-domain OCT, were not seen. In addition, advanced visualization of SD-OCT data demonstrates a hyperreflective ring around the outer retinal hole. ConclusionsSD-OCT can be used...

2011-01-01

384

High-Gain Lasing and Polarization Switch with a Distributed Optical-Klystron Free-Electron Laser  

International Nuclear Information System (INIS)

This Letter reports the first experimental results from the world's first distributed optical-klystron (DOK) free-electron laser (FEL), the DOK-1 FEL, at Duke University. The DOK-1 FEL is a hybrid system, comprised of four wigglers: two horizontal and two helical. With the DOK-1 FEL, we have obtained the highest FEL gain among all storage ring based FELs at 47.8% (#+-#2.7%) per pass. We have also demonstrated that the FEL gain can be enhanced by increasing electron bunching using wigglers with a different polarization. Furthermore, we have realized controlled polarization switches of the FEL beam by a nonoptical means through the manipulation of a buncher magnet.

2006-06-09

385

Gross decontamination experiment report  

International Nuclear Information System (INIS)

A Gross Decontamination Experiment was conducted on various levels and surfaces of the TMI - Unit 2 reactor building in March 1982. The polar crane, D-rings, missile shields, refueling canals, refueling bridges, equipment, and elevations 305' and 347'-6'' were flushed with low pressure water. Additionally, floor surfaces on elevation 305' and floor surfaces and major pieces of equipment on elevation 347'-6'' were sprayed with high pressure water. Selective surfaces were decontaminated with a mechanical scrubber and chemicals. Strippable coating was tested and evaluated on equipment and floor surfaces. The effectiveness, efficiency, and safety of several decontamination techniques were established for the large, complex decontamination effort. Various decontamination equipment was evaluated and its effectiveness was documented. Decontamination training and procedures were documented and evaluated, as were the support system and organization for the experiment.

386

Geometry effects in the pulsed magnetization of high-temperature superconductor bulk parts  

International Nuclear Information System (INIS)

The dynamic response of cylindrical and ring-shaped YBaCuO bulk parts to pulsed magnetic fields is calculated by using small sets of finite elements. Some comparisons with experimental results are provided, and they give confidence in the modelling of the superconducting properties. Transient magnetizations as a function of time and space as well as shapes and absolute values of trapped magnetic flux profiles are presented. The influence of the sample geometry is investigated for different millisecond pulsed magnetization processes. Results are reported for different radial thicknesses and heights, different pulse durations, peak magnetic fields and pulse sequences with and without stepwise cooling. Comparisons concerning the achievable trapped magnetic field and flux are made, and implications for the use of high-temperature superconductor bulk parts as cryo-permanent magnets in potential applications like electric machinery are discussed.

2005-02-01

387

Gamma-ray spectrometric analysis of nuclides formed in thorium by neutron irradiation  

International Nuclear Information System (INIS)

Gamma-ray spectrometric analysis was employed to determine the nuclides formed in thorium by neutron irradiation. Thorium sample was irradiated by neutron from a pure thermal neutron field, neutron field of Cd ratio of about 4, and epithermal neutron field, respectively. The former irradiation was carried out in a thermal neutron column provided for medical uses of neutrons, and the latters were done in the F-ring position of TRIGA II research reactor of Musashi Institute of Technology. The gamma-ray spectra were obtained and analyzed by employing a fully automatic gamma-ray analysis system named ''GAMA: giant frog:-SYSTEM'' developped by Musashi Institute of Technology. The formation of Pa-233 (U-233) was discussed quantitatively with respect to the difference of the neutron field. (author).

1985-02-01

388

Fundamental limits on beam stability at the advanced photon source  

International Nuclear Information System (INIS)

Orbit correction is now routinely performed at the few-micron level in the Advanced Photon Source (APS) storage ring. Three diagnostics are presently in use to measure and control both AC and DC orbit motions: broad-band turn-by-turn rf beam position monitors (BPMs), narrow-band switched heterodyne receivers, and photoemission-style x-ray beam position monitors. Each type of diagnostic has its own set of systematic error effects that place limits on the ultimate pointing stability of x-ray beams supplied to users at the APS. Limiting sources of beam motion at present are magnet power supply noise, girder vibration, and thermal timescale vacuum chamber and girder motion. This paper will investigate the present limitations on orbit correction, and will delve into the upgrades necessary to achieve true sub-micron beam stability.

1998-12-10

389

First observation of excited states in the T_z=1/2 nucleus "8"5Mo  

International Nuclear Information System (INIS)

Excited states in the T_z=(1/2) nucleus "8"5Mo have been observed for the first time with the reaction "5"8Ni("3"2S,#alpha#n#gamma#) at 105 MeV. #gamma#-ray transitions in this nucleus have been assigned unambiguously by combining the information from the GASP #gamma#-ray array, the ISIS silicon ball, and the n-Ring neutron detector. Two band structures have been observed in this nucleus; they continue the smooth evolution of the known bands from the lighter N=43 isotones and have been tentatively assigned spins and parity on this basis. After reaching a maximum of collectivity at "8"3Zr, the trend with increasing mass is reversed, showing a smaller collectivity at "8"5Mo. The rotational behavior of the observed bands is discussed on the basis of the projected shell model calculations.

2002-03-01

390

Excess and deviation properties for the binary mixtures of methylcyclohexane with benzene, toluene, p-xylene, mesitylene, and anisole at T = (298.15, 303.15, and 308.15) K  

International Nuclear Information System (INIS)

Experimental data on density, viscosity, and refractive index at T = (298.15, 303.15, and 308.15) K, while speed of sound values at T = 298.15 K are presented for the binary mixtures of (methylcyclohexane + benzene), methylbenzene (toluene), 1,4-dimethylbenzene (p-xylene), 1,3,5-trimethylbenzene (mesitylene), and methoxybenzene (anisole). From these data of density, viscosity, and refractive index, the excess molar volume, the deviations in viscosity, molar refraction, speed of sound, and isentropic compressibility have been calculated. The computed values have been fitted to Redlich-Kister polynomial equation to derive the coefficients and estimate the standard errors. Variations in the calculated excess quantities for these mixtures have been studied in terms of molecular interactions between the component liquids and the effects of methyl and methoxy group substitution on benzene ring.

2006-12-01

391

Effects of carbon fiber surface treatment on the friction and wear behavior of 2D woven carbon fabric/phenolic composites  

British Library Electronic Table of Contents (United Kingdom)

To improve the friction and wear behavior of carbon fabric reinforced polymer composites (CFRP), nano-SiO2 was deposited on the fabric surface. The friction and wear behavior of the resulting composites were investigated on a model ring-on-block test rig. Experimental results revealed that fiber surface treatment contributed to largely improve the tribological properties of the CFRP composites. Scanning electron microscope (SEM) investigation showed that the worn surface of the surface modified CFRP composite was smoother under given load and sliding rate. Field emission scanning electron microscopy (FESEM), FTIR and X-ray photoelectron spectroscopy (XPS) studies of the carbon fiber surface showed that nanostructured Sio2 thin film can be obtained by SiO2 sols deposition, which improved th...

2009-01-01

392

Diesel exhaust inhalation induces heat shock protein 70 expression in vivo  

British Library Electronic Table of Contents (United Kingdom)

Exposure to urban air pollution is an independent risk factor for increased cardiovascular diseases. Heat shock protein 70 (HSP70) has been implicated in the pathogenesis of vascular dysfunction and cardiovascular diseases. This study has been designed to determine whether inhalation of urban air induces HSP70 expression in the lung and blood as well as the association of HSP70 and air pollution-induced vascular dysfunction. Apolipoprotein E (Apo-E) deficient mice were exposed to diesel exhaust (DE) either acutely (3 days, 200 or 400 g/m3 for 6 h/day) or chronically (7 weeks, 200 or 400 g/m3 for 6 h/day). HSP70 was measured in the lung using immunohistochemistry, and in the plasma by ELISA. Abdominal aorta rings were used to determine vascular functional responses. Chronic DE-exposure incr...

2011-01-01

393

Design of a far-infrared CHI wiggler free-electron laser  

Energy Technology Data Exchange (ETDEWEB)

The preliminary design of a far-infrared free-electron laser with a Coaxial Hybrid Iron (CHI) wiggler is presented. The CHI wiggler consists of a central rod and outer ring of alternating ferrite and dielectric spacers. A periodic wiggler field is produced when the CHI structure is immersed in an axial magnetic field. The design under investigation makes use of 1A, 1MV annular electron beam interacting with the TE{sub 01} coaxial waveguide mode at approximately 1 THz ({lambda} = 300 {mu}m). The nominal wiggler period is 0.5 cm and the inner and outer waveguide radii are 0.4 and 0.8 cm, respectively. An axial guide field of 5-10 kG is used. The device performance is modeled with slow-time-scale nonlinear code. Self fields and axial velocity spread are included in the model. Theoretical results will be presented.

1995-12-31

394

Design considerations for the magnetic system of a prototype x-ray free electron laser  

Energy Technology Data Exchange (ETDEWEB)

A number of difficult technical challenges need to be solved in the fields of accelerator and free-electron laser (FEL) technologies in order to build an X-ray FEL. One of the tasks well suited to the Advanced Photon Source Low Energy Undulator Test Line (LEUTL) is to take the intermediate step of solving some of the problems of single-pass FEL operation in the ultraviolet range. The existing Advanced Photon Source (APS) linac, in addition to its role of supply positrons for the APS storage ring, will also be used to generate the particle beam for the LEUTL. Here, the design of the magnetic system for the high gain soft x-ray free electron laser is described.

1997-04-01

395

Depth-profiling of vertical sidewall nanolayers on structured wafers by grazing incidence X-ray flourescence  

British Library Electronic Table of Contents (United Kingdom)

The Physikalisch-Technische Bundesanstalt (PTB), Germany's national metrology institute, developed an alignment strategy to specify elemental depth profiling in vertical sidewall layers on structured wafers. For this purpose, PTB's irradiation chamber for 200?mm and 300?mm silicon wafers was used to combine total-reflection X-ray fluorescence (TXRF) and grazing incidence XRF (GIXRF) techniques by employing monochromatized undulator radiation of the BESSY II electron storage ring. 3-D test structures were fabricated to develop an optimal alignment strategy allowing for depth profiling in such nanolayers. The test structures consisted of silicon bars with widths/spacings either in the ?m or in the nm range. In order to be able to differentiate the sidewalls more easily from the remainder of ...

2008-01-01

396

Demonstration of a Tunable-Bandwidth White Light Interferometer using Anomalous Dispersion in Atomic Vapor  

CERN Document Server

The concept of the 'white-light cavity' has recently generated considerable research interest in the context of gravitational wave detection. Cavity designs are proposed using negative (or anomalous) dispersion in an intracavity medium to make the cavity resonate over a large range of frequencies and still maintain a high cavity build-up. This paper presents the first experimental attempt and demonstration of white-light effect in a meter long ring cavity using an intracavity atomic medium. The medium's negative dispersion is caused by bi-frequency Raman gain in an atomic vapor cell. Although the white light condition was not perfectly achieved and improvements in experimental control are still desirable, significantly broad cavity response over bandwidth greater than 20 MHz has been observed. These devices will have potential applications in new generation laser interferometer gravitational wave detectors.

2006-01-01

397

Control of cooling during spray forming of bearing steel billets  

Energy Technology Data Exchange (ETDEWEB)

In an effort to minimize the distortion of bearing steel rings during the production process, 100Cr6 steel billets are spray formed with a unique cooling control system to control the cooling and solidification behavior of the deposits. Effects of heating around the deposits, gas cooling at the substrate bottom and the gas flow over the deposits are investigated both by numerical simulation and experiment. Porosity profiles and microstructures of spray formed bearing steel are examined and evaluated. The investigation results show that the thermal boundary conditions of the deposits play important roles on the cooling and solidification behavior of the deposits, especially at the deposit periphery. Porosity in the 100Cr6 bearing steel deposit can be reduced significantly with the special cooling control system.

2004-10-10

398

Coalification by clay-catalyzed oligomerization of plant monomers. [Methyleugenol  

Science.gov (United States)

During this report period, we have obtained a model of montmorillonite clay, and this model has been of great assistance in visualizing how the chemistry of substrate molecules might be altered as it occurs on the surface of the clay. A stereochemical representation of this montmorillonite model is shown. Of particular significance, this model indicates that hydroxyl groups are located in the center of each siloxane ring on the surface of the montmorillonite clay. These hydroxyl groups might serve to bond substrate molecules to the surface of the clay. The next step in our systematic examination of the radical cation-initiated dimerization of plant monomers from the C{sub 6}-C{sub 3} pool of shikimic acid metabolites was to study the dimerization of cinnamic acid and its derivatives. In the next block of research, we examined the reaction of montmorillonite clay (K-10) with methyleugenol. 2 refs.

1990-01-01

399

Characteristics of wave-particle interaction in a hydrogen plasma  

International Nuclear Information System (INIS)

We study the characteristics of cyclotron wave-particle interaction in a typical hydrogen plasma. The numerical calculations of minimum resonant energy Emin, resonant wave frequency ?, and pitch angle diffusion coefficient D?? for interactions between R-mode/L-mode and electrons/protons are presented. It is found that Emin decreases with ? for R-mode/electron, L-mode/proton and L-mode/electron interactions, but increase with ? for R-mode/proton interaction. It is shown that both R-mode and L-mode waves can efficiently scatter energetic (10 keV-100 keV) electrons and protons and cause precipitation loss at L=4, indicating that perhaps wave-particle interaction is a serious candidate for the ring current decay. (authors)

2008-09-01

400

Catalyzed oxidative degradation of methylene blue by in situ generated cobalt (II)-bicarbonate complexes with hydrogen peroxide  

British Library Electronic Table of Contents (United Kingdom)

Oxidative degradation of methylene blue (MB) by Co^2^+-HCO3^- system with H2O2 in aqueous solution was studied. Nearly complete decolorization of the dye was obtained in less than 50min in diluted NaHCO3 solution (25mM) in the presence of only 20mM Co^2^+ ions. Meanwhile, the conjugated structure and phenyl rings of the MB molecule were destroyed or even broken down into small organic acids and inorganic ions, as indicated by FT-IR spectra and ion-chromatography. Photoluminescence probing and radical scavenging technologies suggested that the reaction of MB degradation in this system mainly involved the generation and participation of hydroxyl radicals. Furthermore, by cyclovoltammetric measurements, the in situ formed different complexes between Co^2^+ and HCO3^- were observed at differen...

2011-01-01

401

Casimir repulsion beyond the dipole regime  

CERN Document Server

We extend a previous result [Phys. Rev. Lett. 105, 090403 (2010)] on Casimir repulsion between a plate with a hole and a cylinder centered above it to geometries in which the central object can no longer be treated as a point dipole. We show through numerical calculations that as the distance between the plate and central object decreases, there is an intermediate regime in which the repulsive force increases dramatically. Beyond this, the force rapidly switches over to attraction as the separation decreases further to zero, in line with the proximity force approximation. We demonstrate that this effect can be understood as a competition between an increased repulsion due to a larger polarizability of the central object interacting with increased fringing fields near the edge of the plate, and attractive forces due primarily to the nonzero thickness of the plate. In comparison with our previous work, we find that using the same plate geometry but replacing the single cylinder with a ...

2011-01-01

402

Calculation of 3-D free electron laser gain: Comparison with simulation and generalization to elliptical cross section  

Energy Technology Data Exchange (ETDEWEB)

In the previous paper, we have derived a dispersion relation for the free electron laser (FEL) gain in the exponential regime taking account the diffraction and electron`s betatron oscillation. Here, we compare the growth rates obtained by solving the dispersion relation with those obtained by simulation calculation for the waterbag and the Gaussian models for the electron`s transverse phase space distribution. The agreement is found to be good except for the limiting case where the Rayleigh length is much longer than the gain length (1-D limit). We also generalize the analysis to the case where the electron beam cross section is elliptical as is usually the case in storage rings, and derive the first-order dispersion relation.

1992-08-01

403

CT findings of malignant lymphoma of the anterior mediastinum. Differentiation from invasive thymoma  

Energy Technology Data Exchange (ETDEWEB)

CT findings were compared retrospectively between 9 cases with malignant lymphoma of the anterior mediastinum and 8 cases with invasive thymoma. CT findings of malignant lymphoma were as follows: (1) The majority of the tumors were bilateral and extended beyond the anterior mediastinum to the other mediastinum compartments. (2) Their margin was either smooth or lobulated. (3) Their density was either homogeneous or heterogeneous. In the case with heterogeneous density, ring, triangle and/or band-like low density areas, just like interspace of fused lymph nodes, were demonstrated. Calcification or cysts could not be shown. (4) Patent inherent vessels without deviation were occasionally demonstrated running through the tumors. (5) The tumors faced and contacted widely to anterior chest wall and often pressed the lung laterally at the anterior parietomediastinal pleural reflection. (6) Pleural implants were not demonstrated. (author).

1989-04-01

404

Banana peel extract mediated synthesis of gold nanoparticles  

British Library Electronic Table of Contents (United Kingdom)

Gold nanoparticles were synthesized by using banana peel extract (BPE) as a simple, non-toxic, eco-friendly 'green material'. The boiled, crushed, acetone precipitated, air-dried peel powder was used to reduce chloroauric acid. A variety of nanoparticles were formed when the reaction conditions were altered with respect to pH, BPE content, chloroauric acid concentration and temperature of incubation. The reaction mixtures displayed vivid colors and UV-vis spectra characteristic of gold nanoparticles. Dynamic light scattering (DLS) studies revealed that the average size of the nanoparticles under standard synthetic conditions was around 300nm. Scanning electron microscopy and energy dispersive spectrometry (EDS) confirmed these results. A coffee ring phenomenon, led to the aggregation of th...

2010-01-01

405

BPS Condensates, Matrix Models and Emergent String Theory  

CERN Document Server

A prescription is given for computing anomalous dimensions of single trace operators in SYM at strong coupling and large $N$ using a reduced model of matrix quantum mechanics. The method involves treating some parts of the operators as "BPS condensates" which, in certain limit, have a dual description as null geodesics on the $S^5$. In the gauge theory, the condensate is similar to a representative of the chiral ring and it is described by a background of commuting matrices. Excitations around these condensates correspond to excitations around this background and take the form of ``string bits" which are dual to the "giant magnons" of Hofman and Maldacena. In fact, the matrix model approach gives a {\\it quantum} description of these string configurations and explains why the infinite momentum limit suppresses the quantum effects. This method allows, not only to derive part of the classical sigma model Hamiltonian of the dual string (in the infinite momentum ...

2007-01-01

406

Approach to the homoerythrina alkaloids using a tandem N-alkylation/azomethine ylide cycloaddition.  

Science.gov (United States)

Synthetic efforts toward the homoerythrina alkaloids 1-3 are described. Two separate model systems guided the pivotal [3 + 2] azomethine ylide cycloaddition cascade to form the A-C rings of these alkaloids. The cycloaddition precursors 63 and 68, prepared in nine and ten steps, respectively, from alkyne 47, each contain an enolizable ketone, a tethered electrophile, and an electron-poor dipolarophile. Heating 63 and 68 with the stannyl amine 17 generated demethoxyschelhammeridine 65 and demethoxyschelhammericine 70, the products of intramolecular azomethine ylide cycloadditions. Subsequent attempts to install the C-3 methoxy group of 1-3 are also described. PMID:17465572

2007-04-28

407

Antioxidant properties of 4-methylcoumarins in in vitro cell-free systems  

British Library Electronic Table of Contents (United Kingdom)

4-Methylcoumarins that possess two hydroxyl groups ortho to each other in the benzenoid ring have shown to have excellent antioxidant and radical-scavenging properties in different experimental models. Furthermore, they cannot be metabolized by the liver P450 monoxygenases and thus cannot form 3,4-coumarin epoxides, which are believed to be mutagenic. Herein, we present a study on the structure activity relationship of eight synthetic 4-methylcoumarins, carried out by employing a series of different chemical cell-free tests. These compounds were tested by means of three assays involving one redox reaction with the oxidant (DPPH assay, ABTS+ assay and FRAP). Other assays were employed to evaluate the antioxidant properties of the coumarins under investigation against NO, O2- and HClO, which...

2010-01-01

408

Annihilation of antiprotons in light nuclei  

CERN Document Server

CR-39 detectors have been exposed to a 5.9-MeV antiproton beam using the low energy antiproton ring (LEAR) facility at CERN. At this energy, tracks of antiprotons appear in a CR-39 detector after 135 min of etching in 6 M NaOH at 70C. Fluence of the antiproton beam has been determined using track density. We have also found tracks in the etched CR-39 detector at different depths (250-500 mum). These tracks have resulted from the annihilation of antiprotons with the constituents (H, C and O) of the CR-39 detector. The goal of the experiment is to develop a simple and low-cost method to study properties of antiparticles and those formed after annihilation of these particles with the target matter.

2006-01-01

409

Age determination of large live trees with inner cavities: radiocarbon dating of Platland tree, a giant African baobab  

British Library Electronic Table of Contents (United Kingdom)

? Introduction For large trees without a continuous sequence of growth rings in their trunk, such as the African baobab (Adansonia digitata L.), the only accurate method for age determination is radiocarbon dating. As of today, this method was limited to dating samples collected from the remains of dead specimens. ? Methods Our research extends significantly the dating of such trees to large live specimens with inner cavities. The new approach is based on collecting samples from the cavities and their subsequent radiocarbon dating. ? Results The giant two-stemmed Platland tree, also known as Sunland baobab, was investigated by using this new approach. AMS radiocarbon dates of the oldest sample segments originating from the two inner cavities indicate that the large stem I (364.5?m3) is 750...

2011-01-01

410

Activities on free electron laser in Japan  

International Nuclear Information System (INIS)

The free-electron laser (FEL) projects that are currently in progress in Japan are discussed. Particular attention is given to the storage ring FELs at the Electrotechnical Laboratory, the Institute for Molecular Physics, and the Kyushu University; the superconducting linear accelerator (SC linac) FELs being developed at the Japan Atomic Energy Research Institute; and the RF-linac FEL being developed by the Nuclear Engineering Research Laboratory of the University of Tokyo, the Institute of Scientific and Industrial Research of Osaka University, the Mitsubishi Electric Company, and Tokyo Institute of Technology. Consideration is also given to the microtron FEL being constructed at the Nihon University; the induction-linac and pulseline FELs of the Institute of Laser Engineering of Osaka University, the Institute of Physical and Chemical Research, the National Laboratory for High-Energy Physics, and ISAS; and the Smith-Purcell-effect FEL developed by Tohoku ...

1989-04-24

411

Performance Assessment Monitoring Plan for the Hanford Site Low-Level Burial Grounds  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy Order 435.1, Radioactive Waste Management, requires a disposal authorization statement authorizing operation (or continued operation) for low-level waste disposal facilities. In fulfillment of these requirements, a disposal authorization statement was issued on October 25, 1999, authorizing the Hanford Site to transfer, receive, possess, and dispose of low-level radioactive waste at the 200 East Area burial grounds and the 200 West Area burial grounds. One of the conditions is that monitoring plans for the 200 East Area and 200 West Area low-level burial grounds be written and approved by the Richland Operations Office. As a result of a record of decision for the Hanford Site Solid Waste Program and acceptance of the Hanford Site Solid Waste Environmental Impact Statement, the use of the low-level burial ground (LLBG) as a disposal facility for low-level and mixed low-level wastes has been restricted to lined trenches and the Navy reactor-compartment ...

2006-03-30

412

The crystal structure of YPdSi, the isotopic compounds LnPdSi (Ln=Gd-Lu), and their structural relation to some other equiatomic compounds of the rare earth and transition metals with main group elements  

International Nuclear Information System (INIS)

The nine title compounds were prepared from the elements by arc-melting and subsequent heat treatment in resistance and high-frequency furnaces. The crystal structure of these isotypic compounds was determined for YPdSi from single-crystal X-ray diffractometer data: Pmmn, a = 430.8(1) pm, b = 1391.2(1) pm, c = 743.1(1) pm, Z = 8, R = 0.024 for 417 structure factors and 40 variable parameters. The crystal structures of the isotypic compounds GdPdSi and ErPdSi were also refined from single-crystal data. The structure is of a new type. It consists of condensed, six-membered rings of alternating palladium and silicon atoms with Pd-Si bond distances varying between 249.6 and 258.8 pm. These two-dimensionally infinite nets are connected to each other via weak Pd-Si and Si-Si bonds with bond distances of 276.3 and 259.5 pm. The rare earth atoms are situated above and below the six-membered palladium-silicon rings in a manner as it is known for the ...

413

Synthesis, structural characterization, and performance evaluation of resorcinol-formaldehyde (R-F) ion-exchange resin  

International Nuclear Information System (INIS)

The 177 underground storage tanks at the DOE's Hanford Site contain an estimated 180 million tons of high-level radioactive wastes. It is desirable to remove and concentrate the highly radioactive fraction of the tank wastes for vitrification. Resorcinol-formaldehyde (R-F) resin, an organic ion-exchange resin with high selectivity and capacity for the cesium ion, which is a candidate ion-exchange material for use in remediation of tank wastes. The report includes information on the structure/function analysis of R-F resin and the synthetic factors that affect performance of the resin. CS-100, a commercially available phenol-formaldehyde (P-F) resin, and currently the baseline ion-exchanger for removal of cesium ion at Hanford, is compared with the R-F resin. The primary structural unit of the R-F resin was determined to consist of a 1,2,3,4-tetrasubstituted resorcinol ring unit while CS-100, was composed mainly of a 1,2,4-trisubstituted ring. ...

2004-09-10

414

Space charge field in a FEL with axially symmetric electron beam  

Energy Technology Data Exchange (ETDEWEB)

Nonlinear two-dimensional theory of the space charge of an axially symmetric electron beam propagating in combined right-hand polarized wiggler and uniform axial guide fields in a presence of high-frequency electromagnetic wave is presented. The well-known TE{sub 01} mode in a cylindrical waveguide for the model of radiation fields and paraxial approximation for the wiggler field are used. Space charge field components are written in the Lagrange coordinates by the twice averaged Green`s functions of two equally charged infinitely thin discs. For that {open_quotes}compensating charges{close_quotes} method is applied in which an electron ring model is substituted by one with two different radii and signs discs. On this approach the initial Green`s functions peculiarities are eliminated and all calculations are considerably simplified. Coefficients of a twice averaged Green`s function expansion into a Fourier series are obtained by use of corresponding expansion ...

1995-12-31

415

Radioiodination of 3-quinuclidinyl benzilate using a no-carrier-added concentration of iodine-125/sodium-iodine  

Energy Technology Data Exchange (ETDEWEB)

3-Quinuclidinyl benzilate (QNB) is a potent muscarinic antagonist that binds to muscarinic acetylcholine receptors. Iodination of QNB is difficult because it contains rings that are deactivated, while phenol rings are activated. The purpose of this research is to develop an appropriate method for the iodination of QNB at no-carrier-added concentrations of /sup 125/I/NaI. Phenol was chose as the test compound for direct iodination by adding chloramine T and nonradioactive sodium iodide to the phenol in a phosphate buffer and methanol system. A simple method to radioiodinate QNB at several concentrations was developed in situ in the presence of QNB, thallic trifluoroacetate /sup 125/I/NaI, /sup 127/I/NaI, and aluminium chloride. Using milligram amounts of QNB (7.12 x 10/sup -6/ moles), three reaction steps were involved: QNB was reacted with thallic trifluoroacetate at 60/sup 0/C for 24 hours, then radioactive /sup 125/I/NaI and aluminium ...

1986-01-01

416

Photographic surface photometry of NGC 2855 and NGC 6771 galaxies  

International Nuclear Information System (INIS)

Photographic surface photometry in the BV system was carried out two Southern SO's galaxies, NGC 2855 and NGC 6771. B and V isophote maps were obtained as well as geometric and integrated parameters as position angles, inclination, diameters, magnitudes and integrated colors. Each luminosity profile was decomposed into bulge and disk contributions, each component being fitted to convenient laws. For NGC 2855 de Vaucouleurs law described well the bulge whereas the disk showed an exponential distribution. For NGC 6771 the barred nuclear bulge as well as the disk was best fitted by exponential laws. Additional luminosity components due to an inner fragmented ring were identified in NGC 2855 and due to both a quite prominent lens and well defined ring in NGC 6771. In this galaxy the minor axis, oriented almost edge-on, present clues of another luminosity component besides the bulge and the thin disk. For both galaxies the disk central surface ...

2009-05-10

417

Construction and alignment experience of Indus-1 SRS in C.A.T  

International Nuclear Information System (INIS)

A 450 MeV Synchrotron Radiation Source, Indus-1 is being constructed at Centre for Advanced Technology at Indore in central India. This paper narrates our experience in construction and alignment of synchrotron machines which was first of its kind for most of us. Careful design, planning and execution of the work yielded modest results so that alignment accuracies between 0.1 to 0.3 mm could be achieved (in booster synchrotron) and, which have proved to be adequate up till now. The building of the SRS complex was constructed such that machine rings have their foundations isolated from rest of the building. A number of 100 x 150 mm size steel plates were embedded in the concrete of floor and walls to serve as base for reference surveying marks which were established later. The pre-injector and booster ring are enclosed in a radiation shielding zone with separate ventilation system. Dipoles, quadrupoles and a few sextupoles were fiducialised ...

1996-01-01

418

Characterization and properties of monoammine nitroimidazole complexes of platinum (PtCl sub 2 (NH sub 3 )(NO sub 2 Im)). Crystal and molecular structure of cis-Amminedichloro(1-((((2-hydroxyethyl)amino)carbonyl)methyl)-2-nitroimidazole)platinum(II)  

Energy Technology Data Exchange (ETDEWEB)

The characterization of monoammine(nitroimidazole)platinum(II) complexes of structure (PtCl{sub 2}(NH{sub 3})(NO{sub 2}Im)) (NO{sub 2}Im = 1-((((2-hydroxyethyl)amino)carbonyl)methyl)-2-nitroimidazole, Etanidazole (I), 1-(2-nitro-1-imidazolyl)-3-methoxy2-propanol, Misonidazole (II), and 1-(2-hydroxyethyl)-2-methyl-5-nitroimidazole, Metronidazole (III)) is reported. Both is cis and trans isomers may be isolated for II and III. The crystal structure of cis-amminedichloro(1-((((2-hydroxyethyl)amino)carbonyl)methyl)-2-nitroimidazole)platinum(II) has been determined by X-ray diffraction. The crystals are orthorhombic, space group Pnab with cell dimensions a = 14.867 (7) {angstrom}, b = 9.915 (5) {angstrom}, c = 19.015 (9) {angstrom}, and Z = 8. The structure was refined to R = 0.062 and R{sub w} = 0.052. Platinum has the expected square-planar coordination. The Pt-Cl bond trans to the nitroimidazole ligand is shorter (2.269 (3) {angstrom}) than normal. The dihedral angle between the platinum ...

1991-11-27

419

Cerenkov ring imaging and spectroscopy of charged KSTAR interactions at 11 GeV/c  

Energy Technology Data Exchange (ETDEWEB)

The physics and technology of this new Cerenkov detector are discussed, including materials studies, construction techniques, and resolution measurements. Sources of resolution error are individually identified and measured where possible. The results of all studied indicate that the measurement resolution is understood. This work has led to the adoption of a large scale ring imaging detector as part of a new high energy physics spectrometer, the SLD, at the Stanford Linear Accelerator Center. Results from an amplitude analysis of strange meson final states in K/sup /minus//p ..-->.. /ovr K/sub 0//..pi../sup /minus//p interactions are presented. The data derive from a 4 event/nb exposure of the LASS (large Aperture Superconducting Solenoid) spectrometer to an 11 GeV/c K/sup /minus// beam. The data sample consists of /approximately/100,000 vents distributed over the Dalitz plot of the channel. The process is observed to be dominated by the production and decay of ...

1988-11-01

420

Application of the Green's function method to some nonlinear problems of an electron storage ring: Part 1, The Green's function for the Fokker-Planck equation  

Energy Technology Data Exchange (ETDEWEB)

For an electron storage ring the beam size evaluation including beam-beam interaction gives an example of such a problem. Another good example is finding the beam size for a nonlinear machine. The present work gives a way to solve some of these problems, at least in principle. The approach described here is an application of the well known Green's function method, which in this case is applied to the Fokker-Planck equation governing the distribution function in the phase space of particle motion. The new step made in this paper is to consider the particle motion in two degrees of freedom rather than in one dimension, a characteristic of all the previous work. This step seems to be necessary for an adequate description of the problem, at least for the class of problems which are considered below. This work consists of the formal solution of the Fokker-Planck equation in terms of its Green's function and describing the Green's function ...

1982-07-01

421

Accelerators for proton and heavy ion radiotherapy  

Energy Technology Data Exchange (ETDEWEB)

The construction of Heavy Ion Medical Accelerator in Chiba (HIMAC) at the National Institute of Radiological Sciences was completed in December 1993. HIMAC consists of an injector linac, two synchrotron rings, a high energy beam transport system and a beam irradiation system. Its accelerator parameters are based on the medical requirement, and helium, carbon, neon, silicon and argon were selected as the accelerated ion species. It has 3 therapy rooms (A{approx}C). Room A has a vertical irradiation system, Room C horizontal and Room B both vertical and horizontal. Two rings can supply beams independently to the vertical and horizontal irradiation systems. Clinical trial started on June 21 1994, after several basic biological and physics experiments lasting about 2 months. Cancer is the top cause of death in Japan since 1981, and people expect good treatment results at HIMAC. Proton and heavy ion radiotherapy has the advantage of dose ...

1995-03-01

422

Accelerator technology program. Progress report, April-December 1978  

Science.gov (United States)

This report presents highlights of activities in the Acceleartor Technology (AT) Division from April through December 1978. The report is divided into 10 sections to cover work done by the four groups that make up AT Division (AT-1, AT-2, AT-3, and AT-4). Section I is a brief summary of the whole report. Sections II through VI describe work done by At-1, the Linac Technology Group. Subjects covered are the Pion Generation for Medical Irradiation Program, the Electronuclear Fuel-Producing Accelerator Program, the Gyrocon rf Amplifier Program, the Electron Linear Accelerator Program, and the Free Electron Laser Program. Section VII covers the Linear Accelerator Beam Dynamics development, and Sec. VIII deals with work with the H/sup -/ Ion Source. Most of the work in Secs. VII and VIII was done by AT-2, the Special Projects Group, although work on factors influencing emittance growth was done by MP-9, and results on emittance growth in the new European Council for Nuclear Research (CERN) ...

1980-05-01

423

The Waste Isolation Pilot Plant: A Success Story with International Cooperation  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy (DOE) Carlsbad Field Office (CBFO) administers and operates the Waste Isolation Pilot Plant (WIPP) site, which hosts a deep geologic repository for safe disposal of U.S. defense-related TRU waste and is located 42 kilometers (km) east of Carlsbad, New Mexico. CBFO also manages the National Transuranic Waste Program (NTP), which oversees TRU waste management from generation to disposal. The WIPP began receiving waste in March 1999. In some areas of broad international interest, the CBFO has developed a leading expertise through its 25-year WIPP repository and TRU waste characterization activities. In addition to participating in relevant and beneficial experiments, the CBFO will provide the international community convenient access to this information by sponsoring and hosting symposia and workshops on relevant topics and by participation in international waste management organizations and topical meetings. In recognition of the successes at WIPP, the Inter ...

2002-02-26

424

The Two-Column Aerosol Project (TCAP) Science Plan  

Energy Technology Data Exchange (ETDEWEB)

The Two-Column Aerosol Project (TCAP) field campaign will provide a detailed set of observations with which to (1) perform radiative and cloud condensation nuclei (CCN) closure studies, (2) evaluate a new retrieval algorithm for aerosol optical depth (AOD) in the presence of clouds using passive remote sensing, (3) extend a previously developed technique to investigate aerosol indirect effects, and (4) evaluate the performance of a detailed regional-scale model and a more parameterized global-scale model in simulating particle activation and AOD associated with the aging of anthropogenic aerosols. To meet these science objectives, the Atmospheric Radiation Measurement (ARM) Climate Research Facility will deploy the ARM Mobile Facility (AMF) and the Mobile Aerosol Observing System (MAOS) on Cape Cod, Massachusetts, for a 12-month period starting in the summer of 2012 in order to quantify aerosol properties, radiation, and cloud characteristics at a location subject ...

2011-07-27

425

Spectroscopy of /sup 87,88,89/Sr with (n,. gamma. ) and (d,p) reactions  

Science.gov (United States)

Over the recent years the nuclear structure around the N = 50 shell closure, which is very pronounced in the strontium and zirconium isotopes, has been the subject of extensive experimental and theoretical work. On the proton side Z = 38 and Z = 40 provide fairly closed sub-shells. In the strontium isotopes the lg/sub 9/2/ neutron shell is closed at /sup 88/Sr, supplying relatively pure neutron-hole and neutron-particle states with large spectroscopic factors in /sup 87/Sr and /sup 89/Sr, as well as core-coupled states. The mass region is thus ideally suited to examine the transition from a correlated to an uncorrelated (chaotic.) excitational behavior. These two types are characterized e.g. by the density of excited states, the transition strengths, and the spectroscopic factors observed in transfer reactions. We conducted (n,..gamma..) and (d,p) reactions leading to /sup 87,88,89/Sr in addition to /sup 88/Sr(d,t)/sup 87/Sr and 24 keV neutron capture in /sup ...

1988-01-01

426

Spectroscopy of /sup 87,88,89/Sr with (n,#gamma#) and (d,p) reactions  

International Nuclear Information System (INIS)

Over the recent years the nuclear structure around the N = 50 shell closure, which is very pronounced in the strontium and zirconium isotopes, has been the subject of extensive experimental and theoretical work. On the proton side Z = 38 and Z = 40 provide fairly closed sub-shells. In the strontium isotopes the lg/sub 9/2/ neutron shell is closed at "8"8Sr, supplying relatively pure neutron-hole and neutron-particle states with large spectroscopic factors in "8"7Sr and "8"9Sr, as well as core-coupled states. The mass region is thus ideally suited to examine the transition from a correlated to an uncorrelated (chaotic?) excitational behavior. These two types are characterized e.g. by the density of excited states, the transition strengths, and the spectroscopic factors observed in transfer reactions. We conducted (n,#gamma#) and (d,p) reactions leading to /sup 87,88,89/Sr in addition to "8"8Sr(d,t)"8"7Sr and 24 keV neutron capture in "8"8Sr. The vast amounts of data ...

1988-04-24

427

Some important aspects of fragment angular momentum in medium energy fission of {sup 238}U  

Energy Technology Data Exchange (ETDEWEB)

Independent isomeric yield ratios of {sup 131}Te, {sup 133}Te and {sup 134}I have been determined at five different energies in the range of 25-44 MeV alpha particle induced fission of {sup 238}U using radiochemical and gamma spectrometric techniques. From the independent isomeric yield ratios, fragment angular momenta (J{sub rms}) have been deduced using a statistical model analysis. The J{sub rms} were also calculated theoretically based on thermal equilibration of various collective modes after considering the occurrence of multichance fission. These data and the literature data for various fragments in the mass region 126-136 in {sup 238}U ({alpha},f), {sup 238}U (p,f) and {sup 238}U ({gamma},f) show the following important features: (i) Both the entrance channel excitation energy and input angular momentum affect the fragment angular momentum in the exit channel. (ii) There are two groups of fission products from the point of view of change of fragment angular momentum with ...

1999-03-15

428

Penning trap mass spectrometry of neutron-rich Fe and Co isotopes around N=40 with the LEBIT mass spectrometer  

International Nuclear Information System (INIS)

Penning trap mass spectrometry is presented as a complementary tool to nuclear spectroscopy experiments for the study of nuclear structure in the vicinity of N=40, Z=28. High-precision mass measurements of the "6"3"-"6"6Fe and "6"4"-"6"7Co isotopes have been carried out with the Low Energy Beam and Ion Trap (LEBIT) Penning trap mass spectrometer. The newly obtained mass values for "6"6Fe and "6"7Co are presented, together with the previously reported LEBIT mass measurements in this region. In the case of "6"5Fe the existence of a new isomer is reported, and an isomer recently discovered by decay spectroscopy in "6"7Co is confirmed. Relative mass uncertainties as low as 4x10"-"8 are obtained. All mass values are found to be in good agreement with previous experimental results with the exception of "6"4Co, where a 5#sigma# deviation is observed. Using these data the two neutron separation energies S_2_n are calculated. However, the large error bars in the mass values of the neighbor Fe ...

2010-04-01

429

Nuclear Waste Management - A Need to Ensure that the Waste Decays While the Knowledge Does Not  

International Nuclear Information System (INIS)

The unique time scales associated with nuclear waste management require active work to preserve the knowledge associated with programs that can often span long time frames. For example, repository programs are designed and developed for the safe containment of radionuclides with half-lives on the order of 24,000 years (for Pu-239). Performance assessment studies are required to show, by predictive modeling, that these repositories can safely contain the waste for tens of thousands of years, with one million years a reality in the debate. Development of successful repository programs can span several decades. Once operational, a repository is expected to function until closure for a period of 30 to 40 years. Yet, the decision makers at all levels in such a repository program exert influence and authority over much shorter periods of time (e.g., four years for executive appointments). A discontinuous decision-making process and the associated potential for loss of ...

430

Joining of zirconium alloys  

International Nuclear Information System (INIS)

Alloys of zirconium are widely used in various core components of power reactors. Nuclear assemblies require high degree of reliability and integrity for performing in radiation and corrosive atmosphere. The hostile environments of reactor core and inaccessibility for repairs make it mandatory to select only those joining techniques which produce not only superior quality but are also amenable to NDT methods and such other techniques which ensure acceptable performance. The author has worked on various types of welding of zirconium alloys for different applications. Modern techniques in electron beam (EB) welding, resistance welding, GTAW welding and laser welding have been developed for joining Zr alloys components for different types of reactors. Many of these have been standardized and successfully used in production. Several advancements have been made in the welding technologies towards achieving high productivity and increased reliability with economy and adaptability. EB, laser, ...

2002-09-11

431

Horizontal Steam Generator Thermal-Hydraulics at Various Steady-State Power Levels  

Science.gov (United States)

Three-dimensional computer simulation and analyses of the horizontal steam generator thermal-hydraulics of the WWER 1000 nuclear power plant have been performed for 50% and 75% partial loads, 100% nominal load and 110% over-load. Presented results show water and steam mass flow rate vectors, steam void fraction spatial distribution, recirculation zones, swell level position, water mass inventory on the shell side, and other important thermal-hydraulic parameters. The simulations have been performed with the computer code 3D ANA, based on the 'two-fluid' model approach. Steam-water interface transport processes, as well as tube bundle flow resistance, energy transfer, and steam generation within tube bundles are modelled with {sup c}losure laws{sup .} Applied approach implies non-equilibrium thermal and flow conditions. The model is solved by the control volume procedure, which has been extended in order to take into account the 3D flow of liquid ...

2002-07-01

432

Horizontal Steam Generator Thermal-Hydraulics at Various Steady-State Power Levels  

International Nuclear Information System (INIS)

Three-dimensional computer simulation and analyses of the horizontal steam generator thermal-hydraulics of the WWER 1000 nuclear power plant have been performed for 50% and 75% partial loads, 100% nominal load and 110% over-load. Presented results show water and steam mass flow rate vectors, steam void fraction spatial distribution, recirculation zones, swell level position, water mass inventory on the shell side, and other important thermal-hydraulic parameters. The simulations have been performed with the computer code 3D ANA, based on the 'two-fluid' model approach. Steam-water interface transport processes, as well as tube bundle flow resistance, energy transfer, and steam generation within tube bundles are modelled with "closure laws". Applied approach implies non-equilibrium thermal and flow conditions. The model is solved by the control volume procedure, which has been extended in order to take into account the 3D flow of liquid and gas phase. The ...

2002-04-14

433

High-field MR imaging in the follow-up of patients with valvular and composite tubular aortic prostheses  

International Nuclear Information System (INIS)

Eleven patients who had undergone cardiac surgery were studied by means of high-field MR imaging (1.5 T). Six patients had aortic root and valve replaced with a Bjork-Shiley (BS) composite tubular aortic graft prosthesis for acute dissection of ascending aorta. In the other 5 patients with rheumatic calcific aortic disease, the valve had been replaced with a BS prosthesis. As a whole, MR studies were 14. Previous evaluations of magnetic field effects had seem carried out ex vivo on both BS valves and BS composite prostheses, on surgical ligation clips (Tantalium and Stainless) and on stainless wires for sternal closure. In 4 patients (2 BS composite grafts, and 2 BS valves) MRI diagnosed chronic dissection of both arch and descending aorta. In 1 of them, with a bs valve, associated localized acute dissection of ascending aorta was observed. In 3 patients with BS composite grafts, MRI revealed pseudo-aneurysms (including a thrombosed one) at the graft level. In one ...

434

Ground penetrating radar and direct current resistivity evaluation of the desiccation test cap, Savannah River Site  

Energy Technology Data Exchange (ETDEWEB)

The Savannah River Site (SRS) has a variety of waste units that may be temporarily or permanently stabilized by closure using an impermeable cover to prevent groundwater infiltration. The placement of an engineered kaolin clay layer over a waste unit is an accepted and economical technique for providing an impermeable cover but the long term stability and integrity of the clay in non-arid conditions is unknown. A simulated kaolin cap has been constructed at the SRA adjacent to the Burial Ground Complex. The cap is designed to evaluate the effects of desiccation on clay integrity, therefore half of the cap is covered with native soil to prevent drying, while the remainder of the cap is exposed. Measurements of the continuing impermeability of a clay cap are difficult because intrusive techniques may locally compromise the structure. Point measurements made to evaluate clay integrity, such as those from grid sampling or coring and made through a soil cover, may miss ...

1996-04-01

435

F-Area Seepage Basins groundwater monitoring report -- third and fourth quarters 1993. Volume 1  

Energy Technology Data Exchange (ETDEWEB)

During the second half of 1993, the groundwater at the F-Area Seepage Basins (FASB) was monitored in compliance with Module 3, Section C, of South Carolina Hazardous Waste Permit SC1-890-008-989, effective November 2, 1992. The monitoring well network is composed of 87 FSB wells screened in the three hydrostratigraphic units that make up the uppermost aquifer beneath the FASB. A detailed description of the uppermost aquifer is included in the Resource Conservation and Recovery Act Part B post-closure care permit application for the F-Area Hazardous Waste Management Facility submitted to the South Carolina Department of Health and Environmental Control (SCDHEC) in December 1990. Beginning in the first quarter of 1993, the standard for comparison became the SCDHEC Groundwater Protection Standard (GWPS) specified in the approved F-Area Seepage Basins Part B permit. Currently and historically, gross alpha, nitrate, nonvolatile beta, and tritium are among the primary ...

1994-03-01

436

Ecological risk assessments for protected migratory birds and marine species at Midway Atoll  

Energy Technology Data Exchange (ETDEWEB)

In June 1997, the US Navy plans to close its Naval Air Facility on Sand Island and transfer the atoll to the US Fish and Wildlife Service for use as a National Wildlife Refuge. Midway provides breeding and feeding habitat for migratory seabirds, terrestrial and marine mammals, sea turtles and other reptiles, and a variety of reef fishes and invertebrates. As part of the base closure and transfer process, 36 sites of potential environmental concern were identified on Sand and Eastern islands. These sites include landfills and uncontrolled disposal areas, hazardous materials storage areas, abandoned transformers, sewer outfalls, and other potential hazardous waste sites. Potential contaminants include pesticides, PAHs, PCBs, and heavy metals. A screening ecological risk assessment was performed at each site with a goal of determining whether contaminants could pose any current or future risks to protected migratory bird or marine mammal wildlife species. Specific ...

1995-12-31

437

Development of the Decontamination Approach for the West Valley Demonstration Project Decontamination Project Plan  

Energy Technology Data Exchange (ETDEWEB)

This paper details the development of a decontamination approach for the West Valley Demonstration Project (WVDP), Decontamination Project Plan (Plan). The WVDP is operated by West Valley Nuclear Services Company (WVNSCO), a subsidiary of Westinghouse Government and Environmental Services, and its parent companies Washington Group International and British Nuclear Fuels Limited (BNFL). The WVDP is a waste management effort being conducted by the United States Department of Energy (DOE) at the site of the only commercial nuclear fuel reprocessing facility to have operated in the United States. This facility is part of the Western New York Nuclear Service Center (WNYNSC), which is owned by the New York State Energy Research and Development Authority (NYSERDA). As authorized by Congress in 1980 through the West Valley Demonstration Project Act (WVDP Act, Public Law 96-368), the DOE's primary mission at the WVDP is to solidify high-level liquid nuclear waste safely; transport the ...

2002-02-25

438

Development of a system model for the postclosure assessment of a concept for geological disposal of Canada`s nuclear fuel waste  

Energy Technology Data Exchange (ETDEWEB)

Atomic Energy of Canada has recently submitted for regulatory and public review an Environmental Impact Statement (EIS) on a concept for disposal of Canada`s nuclear fuel waste. The EIS is supported by nine primary references that summarize major aspects of the concept, including a postclosure environmental and safety assessment. The scope of the postclosure assessment is largely determined by the requirements of the Atomic Energy Control Board (AECB) of Canada. These requirements include a quantitative estimate of the annual effective dose equivalent to an individual in the most exposed group of people (the critical group) for 10,000 years following closure of the disposal facility, and a radiological risk criterion with an associated dose rate limit of 0.05 mSv/a. Over this long time frame, a quantitative assessment cannot be based on actual observations, and thus we use scientific arguments and simulations with mathematical models to infer long-term behavior and ...

1995-12-01

439

Description of work vadose drilling at the 1301-N and 1325-N facilities, 100-NR-1 operable unit  

Energy Technology Data Exchange (ETDEWEB)

This description of work (DOW) details the field activities associated with the sampling of the vadose zone soils beneath the 1301-N and 1325-N cribs and trenches and will serve as a field guide for those performing the work. These activities are undertaken pursuant to the Hanford Federal Facility Agreement and Consent Order (Ecology et al., 1994a) Milestone M-16-94-01H-Tl and the June 30, 1994 Milestone Change Request M-16-94-02 (Ecology et al., 1994b). Three vadose zone borings, 1301-N-1, 1301-N-2, and 1325-N-1, will be constructed to investigate the vertical and horizontal distribution of radionuclide contamination in sediments beneath the cribs and trenches. The boreholes are also intended to intersect subsurface areas that may have been contaminated by dangerous wastes, i.e., metals, in effluent disposed during past operation of the facilities. This limited field investigation will provide data for the evaluation of remedial alternatives. Data from the investigation are expected ...

1994-08-01

440

Data of spleen-scintiscanning after splenectomy  

International Nuclear Information System (INIS)

In 65 adult rabbits of both sexes (2.5 to 6 kg) the following salvaging procedures were performed after simulated trauma: (1) Continuous suture line; (2) closure with fibrin sealant after temporary clamping; (3) hemisplenectomy with omental wrap; (4) suture fixation of fragments and slices of spleen tissue to the peritoneum; (5) suture fixation of spleen fragments to the omentum; (6) extraperitoneal subcutaneous transposition of spleen cubes. In addition, the likelihood of spontaneous splenosis was examined in a preliminary study involving 5 animals by introducing unattached spleen meal and fragments. Scanning was repeated 4 to 12 weeks postoperatively. The functional competence of minor parenchymal islands was also investigated with well counter measurements of organ and muscle tissue homogenates. Spontaneous splenosis after abdominal injuries was not found to be the rule. Salvaging procedures at the natural vascular hilus by sutures, fibrin sealant and ...

441

Characterization of the corrosion behavior of the carbon steel liner in Hanford Site single-shell tanks  

Energy Technology Data Exchange (ETDEWEB)

Six safety initiatives have been identified for accelerating the resolution of waste tank safety issues and closure of unreviewed safety questions. Safety Initiative 5 is to reduce safety and environmental risk from tank leaks. Item d of Safety Initiative 5 is to complete corrosion studies of single-shell tanks to determine failure mechanisms and corrosion control options to minimize further degradation by June 1994. This report has been prepared to fulfill Safety Initiative 5, Item d. The corrosion mechanisms that apply to Hanford Site single-shell tanks are stress corrosion cracking, pitting/crevice corrosion, uniform corrosion, hydrogen embrittlement, and microbiologically influenced corrosion. The corrosion data relevant to the single-shell tanks dates back three decades, when results were obtained from in-situ corrosion coupons in a few single-shell tanks. Since that time there have been intertank transfers, evaporation, and chemical alterations of the waste. ...

1994-06-01

442

Chalon/Saint-Marcel manufacturing plant; L'usine de Chalon/Saint-Marcel  

Energy Technology Data Exchange (ETDEWEB)

AREVA is the world leader in the design and construction of nuclear power plants, the manufacture of heavy components, and the supply of nuclear fuel and nuclear services such as maintenance and inspection. The Equipment Division provides the widest range of nuclear components and equipment, manufactured at its two facilities in Jeumont, northern France, and St. Marcel, in Burgundy. The St. Marcel plant, set on 35 ha (87.5 acres) near Chalon-sur-Saone, was established in 1973 in a region with a long history of specialized metalworking and mechanical activities to meet the demand for non-military nuclear requirements in France. The site offers two advantages: - excellent facilities for loading and transporting heavy components on the Saone river, - it's proximity to other group sites. Since its completion in 1975, the Chalon/St. Marcel facility has manufactured all the heavy components for French pressurized water reactors (PWRs) ranging from 900 MW to 1500 MW. It has also ...

2008-07-01

443

CFD simulation of steam generator tube rupture thermal-hydraulics  

Energy Technology Data Exchange (ETDEWEB)

Several steam generator tube rupture accidents have occurred at plants in the past. In this paper the Computational Multi-Fluid Dynamics (CMFD) investigation of the horizontal steam generator thermal-hydraulics during the tube rupture accident is performed. A guillotine of a steam generator U-tube is assumed with choked flow from the primary to the secondary side of the steam generator. We have computed water and steam velocity fields, steam volume fraction distribution on the steam generator secondary (shell) side, as well as the swell level increase. The simulation results are a support to the safety analyses of the steam generator tube rupture accident. Numerical simulation is performed with the multidimensional multi-fluid modelling approach. The two-phase flow around steam generator tubes in the bundle is modelled by the porous media approach. Interfacial mass, momentum and energy transfer are modelled with the closure laws. The governing equations are solved ...

2004-07-01

444

A simulation of the transport and fate of radon-222 derived from thorium-230 low-level waste in the near-surface zone of the Radioactive Waste Management Site in Area 5 of the Nevada Test Site  

Energy Technology Data Exchange (ETDEWEB)

US Department of Energy (DOE) Order 5820.2A (DOE, 1988) requires performance assessments on all new and existing low-level radioactive waste (LLW) disposal sites. An integral part of performance assessment is estimating the fluxes of radioactive gases such as radon-220 and radon-222. Data needs pointed out by mathematical models drive site characterization. They provide a logical means of performing the required flux estimations. Thorium-230 waste, consisting largely of thorium hydroxide and thorium oxides, has been approved for disposal in shallow trenches and pits at the LLW Radioactive Waste Management Site in Area 5 of the Nevada Test Site. A sophisticated gas transport model, CASCADR8 (Lindstrom et al., 1992b), was used to simulate the transport and fate of radon-222 from its source of origin, nine feet below a closure cap of native soil, through the dry alluvial earth, to its point of release into the atmosphere. CASCADR8 is an M-chain gas-phase radionuclide ...

1993-12-01

445

A complete algorithm for synthesizing modular fixtures for polygonal parts  

Energy Technology Data Exchange (ETDEWEB)

Commercially-available nuclear fixturing systems typically include a square lattice of tapped and bushed holes with precision locating and clamping elements that can be rigidly attached to the lattice using dowel pins or expanding mandrels. Currently, human expertise is required to synthesize a suitable arrangements of these elements to hold a given part. Besides being time consuming, if the set of alternatives is not systematically explored, the designer may fail to find an acceptable fixture or may settle upon a suboptimal fixture. We consider a class of modular fixtures that prevent a part from translating or rotting in the plane using four point contacts on the part`s boundary. These fixtures are based on three round locators, each centered on a lattice point, and one translating clamp. We present an algorithm that accepts a polygonal part shape as input and synthesizes the set of all fixture designs that achieve form closure for the given part. The algorithm ...

1993-11-01

446

Triassic petroleum geology, Western Canada Basin and neighbouring Yukon Territory and American regions: Bibliography and summary  

Energy Technology Data Exchange (ETDEWEB)

In the Western Canada Basin, Triassic sedimentary rocks were deposited as a northeasterly-tapering wedge of sediment on the Triassic cratonic Interior Platform and adjacent miogeoclinal areas and occurring within the present day Interior Plains and Rocky Mountain Foothills and Front Ranges of Manitoba, Saskatchewan, Alberta and northeastern British Columbia. Continued drilling activity and recent significant discoveries such as the Spirit River, Brassey, Ring-Pedigree ('Border'), Sukunka, Bullmoose West fields, and new unnamed fields in the Brazion-Monkman area, confirm the petroleum potential of Triassic rocks in this basin. A bibliography of 382 publications and a short test that summarizes the regional setting, stratigraphy and petroleum geology of these Triassic rocks, are provided. This paper is designed to help explorationists or geological researchers become more familiar with Western Canada Basin Triassic rocks and relevant literature. The ...

1993-12-01

447

Thermal analysis of spent fuel in shuttle station during dry transfer under abnormal cooling conditions for TAPS - 4  

International Nuclear Information System (INIS)

A pair of bundles is placed in a shuttle tube, which is enclosed by a carriage tube kept inside the Shuttle Transfer Station (STS). It takes about 90 minutes for the spent fuel bundles to travel from the reactor channel to Transfer Magazine (TM). Subsequently, the dry transfer operation takes about 4 minutes. An emergency air cooling flow rate of 600 m3/hr is supplied to cool the spent fuel bundles after they reach the STS, following lapse of 4 minutes of spent fuel dry transfer, in case the bundles are not submerged in the light water in STS. A thermal and hydraulic safety analysis has been done to estimate the maximum sheath temperature, if the spent fuel bundles are stuck at a location of 30 mm below the normal location aligned to the TM port. This position of the spent fuel will have least cooling from the emergency cooling airflow. At the same time, the shuttle tube carrying the spent fuel bundle is just above the water. From the analysis it has been concluded that peak clad ...

2006-11-13

448

The synthesis of (1',3'- sup 3 H)4-(4'-azido-5',6',7',8'-tetrahydro-5',5',8',8'-tetramethyl -2'-anthracenyl)benzoic acid as a probe of the retinoic acid receptor  

Energy Technology Data Exchange (ETDEWEB)

The synthesis of (1',3'-{sup 3}H)4-(4'-azido-5',6',7',8'-tetrahydro-5'5'8',8'-tetramethyl-2'-anthracenyl)benzoic acid is described. This retinoid was designed as a photoaffinity probe of the receptor sites of cellular retinoic acid-binding protein and the nuclear retinoic acid receptor protein. The ({sup 3}H)azidoretinoid was prepared from 1,2,3,4-tetrahydro-1,1,4,4-tetra-methyl-7-(4-methylphenyl)-5-nitroanthracene in five steps in 15% yield (89% radiochemical purity by HPLC). {sup 1}H and {sup 3}H NMR was used to confirm the sites of {sup 3}H substitution on the ring. (author).

1990-01-01

449

The jet-powered optical nebula of Cygnus X-1  

CERN Document Server

We present H-alpha and [O III] (5007 Angstroms) images of the nebula powered by the jet of the black hole candidate and microquasar Cygnus X-1, observed with the 2.5m Isaac Newton Telescope (INT). The ring-like structure is luminous in [O III] and there exists a thin outer shell with a high [O III] / H-alpha flux ratio. This outer shell probably originates in the collisionally excited atoms close to the front of the bow shock. Its presence indicates that the gas is shock excited as opposed to photoionised, supporting the jet-powered scenario. The shock velocity was previously constrained at 20 = 100 km/s (1 sigma confidence) based on a comparison of the observed [O III] / H-alpha ratio in the bow shock with a number of radiative shock models. From this we further constrain the time-averaged power of the jet: P_Jet = (4 - 14)*10^36 erg/s. The H-alpha flux behind the shock front is typically 4*10^-15 erg/s/cm^2/arcsec^2, and we estimate an upper limit of ~8*10^-15 ...

2007-01-01

450

Synthesis of alkylated deoxyno irimycin and 1,5-dideoxy-1,5-iminoxylitol analogues: : Polar side-chain modification, sulfonium and selenonium heteroatom variants, conformational analysis, and evaluation as glycosidase inhibitors  

DEFF Research Database (Denmark)

The syntheses of N-alkylated deoxynojirimycin and 1,5-dideoxy-1,5-iminoxylitol derivatives having either a D- or an L-erythritol-3-sulfate functionalized N-substituent are reported. The alkylating agent used was a cyclic sulfate derivative, whereby selective attack of the nitrogen atom at the least hindered primary center afforded the desired ammonium salt. In aqueous solution, these salts were configurationally labile at the ammonium center. Sulfonium and/or selenonium analogues of the ammonium salts were prepared by analogous reactions. The chalcogen salts were obtained as mixtures of diastereomers, separable in some cases, differing only in the stereochemistry at the configurationally stable sulfur or selenium atoms. Proof of configuration and conformation of each compound was obtained by detailed NMR experiments. The compounds are six-membered ring analogues of salacinol, a known sulfonium-salt glucosidase inhibitor. Evaluation of the target compounds for ...

2004-01-01

451

Study of e{sup +}e{sup -}{yields}pp using initial state radiation with BABAR  

Science.gov (United States)

The e{sup +}e{sup -}{yields}pp cross section is determined over a range of pp masses, from threshold to 4.5 GeV/c{sup 2}, by studying the e{sup +}e{sup -}{yields}pp{gamma} process. The data set corresponds to an integrated luminosity of 232 fb{sup -1}, collected with the BABAR detector at the PEP-II storage ring, at an e{sup +}e{sup -} center-of-mass energy of 10.6 GeV. The mass dependence of the ratio of electric and magnetic form factors, G{sub E}/G{sub M}, is measured for pp masses below 3 GeV/c{sup 2}; its value is found to be significantly larger than 1 for masses up to 2.2 GeV/c{sup 2}. We also measure J/{psi}{yields}pp and {psi}(2S){yields}pp branching fractions and set an upper limit on Y(4260){yields}pp production and decay.

2006-01-01

452

Structure-retention correlations of hydrocarbons in gas-liquid and gas-solid chromatography. Cycloalkenes and cycloalkadienes  

Energy Technology Data Exchange (ETDEWEB)

The retention indices of cycloalkenes and cycloalkadienes with C/sub 6/-C/sub 13/ rings are determined by gas-liquid chromatography (GLC) on glass capillary columns coated with OV-1 and Ucon LB 550X and by gas-solid chromatrography (GSC) on a microcolumn packed with uncoated graphitized thermal carbon black (GTCB). Structure-retention correlations are derived on using index differences such as H/sup OV/, H/sup GTCB/ and ..delta..I values, considering the differences in the stereochemistry of these compounds. It is shown that the combined application of index increments obtained in GLC and GSC provides more detaled structure informations. The value of the retention index units agree with the most stable conformations of the alicyclic compounds. The high value for the energy equivalent to an index unit (..delta..G/sub I.U./ = 4.18 kJ/mol) confirms that graphitized thermal carbon black causes much stronger dispersive interactions than any nonpolar liquid phase.

1987-08-01

453

Status of 4-cm-aperture, 17-m-long SSC dipole magnet R D program at BNL  

Energy Technology Data Exchange (ETDEWEB)

Over the last year-and-a-half, several 4-cm-aperture, 17-m-long dipole magnet prototypes were built by Brookhaven National Laboratory (BNL) under contract with the Superconducting Super Collider (SSC) Laboratory. These prototypes are the last phase of a half-decade-long R D program, carried out in collaboration with Fermi National Accelerator Laboratory and Lawrence Berkeley Laboratory, and aimed at demonstrating the feasibility of the SSC main ring dipole magnets. They also prepare the way of the 5-cm-aperture dipole magnet program to be started soon. In this paper, we analyze the mechanical behavior of the BNL prototypes during cool-down and excitation, and we attempt to relate this behavior to the magnet features. The data reveal that the mechanical behavior is sensitive to the vertical collar-yoke interference, and that the magnets exhibited somewhat erratic changes in coil end-loading during cool-down. 9 refs., 6 figs.

1991-06-01

454

Stability study of a gyrotron-traveling-wave amplifier based on a lossy dielectric-loaded mode-selective circuit  

Science.gov (United States)

The millimeter microwave source of gyrotron-traveling-wave amplifier (gyro-TWT) is capable of generating high power coherent radiation in a broad bandwidth, while its performance is severely deteriorated by the stability problems. This paper focuses on modeling and the stability analysis of the Naval Research Laboratory (NRL) Ka-band TE{sub 01} mode gyro-TWT based on an interaction circuit alternately loaded with lossy ceramic shells and metal rings. The propagation characteristics of the interaction circuit is analyzed first, based on which the boundary impedance method is employed to build an equivalent uniform lossy circuit. Then the stability of the interaction system is studied using linear and nonlinear theories. The analysis reveals that, due to the special waveguide structure and the dielectric loss, the propagation characteristics of the complex waveguide are similar to that of a uniform lossy circuit. The analysis of the absolute instabilities ...

2009-07-15

455

Stability study of a gyrotron-traveling-wave amplifier based on a lossy dielectric-loaded mode-selective circuit  

International Nuclear Information System (INIS)

The millimeter microwave source of gyrotron-traveling-wave amplifier (gyro-TWT) is capable of generating high power coherent radiation in a broad bandwidth, while its performance is severely deteriorated by the stability problems. This paper focuses on modeling and the stability analysis of the Naval Research Laboratory (NRL) Ka-band TE01 mode gyro-TWT based on an interaction circuit alternately loaded with lossy ceramic shells and metal rings. The propagation characteristics of the interaction circuit is analyzed first, based on which the boundary impedance method is employed to build an equivalent uniform lossy circuit. Then the stability of the interaction system is studied using linear and nonlinear theories. The analysis reveals that, due to the special waveguide structure and the dielectric loss, the propagation characteristics of the complex waveguide are similar to that of a uniform lossy circuit. The analysis of the absolute instabilities characterizes the ...

2009-07-01

456

Short wave length and high qualification of free-electron laser  

International Nuclear Information System (INIS)

The oscillation experiment of free-electron laser (FEL) was carried at the wave length 488 nm. The space and time properties and power of FEL were investigated. The typical macropulse structure indicated the time interval 20 ms and the pulse width 2 to 3 ms. About 1 ns was necessary to build up FEL. The space distribution of FEL showed beautiful TEM_0_0 mode, TEM_0_1 and TEM_0_2 mode. On the basis of data, 39 #mu#W average power was calculated at 2.9 mA accumulated current per bunch by integrating each response of pixel of CCD camera. The peak power was 1.2 W. In the oscillator, FEL power was average 1.2 W, peak 38 kW. On the electron beam, the stability of head tail was controlled by 6-pole-Quadrupole-6-pole (SQS) system made by an experimental basis. We succeeded the single set test, setting up single set in the ring. The characteristic properties of electron beam evaporation mirror of photo oscillator were studied and then new type photo oscillator to obtain ...

1998-02-01

457

Sealing of nuclear plant electrical equipment: Final report  

International Nuclear Information System (INIS)

The nuclear power industry has many applications where electrical equipment is required to operate in environments which contain high relative humidity, steam and water or chemical sprays. Equipment is susceptible to these environments by moisture entering through inherent design provisions such as O-rings and through the electrical interface. The objective of this research is to review electrical interface sealing techniques and to recommend methods for providing effective electrical interface sealing. The most common methods of sealing are the use of electrical fittings containing sealants, add-on assemblies and hardware changeout. The experience gained in several years of testing electrical interface seals on such devices as limit switches, solenoid valves and transmitters is presented to provide information on seal effectiveness and preferred application. The effectiveness of various sealing methods is discussed, each of which is dependent upon the device being ...

458

Results of surface activity and radiation field measurements made during surface decontamination experiments conducted at TMI-2  

International Nuclear Information System (INIS)

The Gross Decontamination Experiment was conducted on various levels and surfaces of the TMI-2 Reactor Building during February and March 1982 and was designed to investigate the effectiveness of various surface decontamination techniques. The polar crane, D-rings, missile shields, refueling canal, fueling bridge, major equipment, floors and some walls were flushed with low pressure water. Water lances were directed manually and applied water at temperatures between ambient and 60"0C at a flow rate of about 95 liters per minute. In addition, floor surfaces on the 305-ft elevation and floor surfaces and major equipment on the 347-ft elevation were sprayed with high pressure water (floors in the Reactor Building are designated by their elevations above sea level). The water pressure in this case varied between 13.8 and 41.4 mPa and water temperature was at a maximum 60"0C. Certain surfaces were also decontaminated using either strippable coatings or a mechanical ...

1984-07-15

459

Remote replacement of TF (toroidal field) and PF (poloidal field) coils for the compact ignition tokamak  

Energy Technology Data Exchange (ETDEWEB)

The use of deuterium-tritium fuel in the Compact Ignition Tokamak will require applying remote handling technology for ex-vessel maintenance and replacement of machine components. Highly activated and contaminated components of the fusion devices auxiliary systems, such as diagnostics and RF heating, must be replaced using remotely operated maintenance equipment in the test cell. In-vessel remote maintenance included replacement of divertor and first wall hardware, faraday shields, and for an in-vessel inspection system. Provision for remote replacement of a vacuum vessel sector, toroidal field coil or poloidal field ring coil was not included in the project baseline. As a result of recent coil failures experienced at a number of facilities, the CIT project decided to reconsider the question of remote recovery from a coil failure and, in January of 1990, initiated a coil replacement study. This study focused on the technical requirements and impact on fusion ...

1990-01-01

460

Relaxant effects of hexosamines on isolated small human placental arteries  

DEFF Research Database (Denmark)

Wharton's jelly contains large amounts of hyaluronic acid, and glucosamine is an important constituent of this macromolecule. In order to evaluate the placental vascular effects of this aminosugar, small chorionic and stem villous arteries were dissected from placental specimens obtained at normal term vaginal deliveries (n = 15). Ring preparations were mounted in organ baths, and isometric wall tensions were measured. Glucosamine and its epimer galactosamine (5 X 10(-4) to 10(-2) M) produced marked relaxation of contractions induced by PGF2 alpha (10(-5) M) in both chorionic and stem villous arteries. The effect was unchanged after pretreatment with atropin, propranolol and indomethacin. The relaxant effect of the neutral sugar mannose was less pronounced compared with that of the hexosamines. Total tissue concentrations of placental hexosamines have been reported within the range needed to produce placental vascular relaxation in the present study. However, the ...

1987-01-01

461

Radiation-induced reduction of ditetrazolium salt in aqueous solutions  

Energy Technology Data Exchange (ETDEWEB)

Color formation in aqueous solutions of the ditetrazolium salt blue tetrazolium (BT{sup 2+}) in the absence or presence of oxygen is a complex radiation chemical reaction. The final stable product is the poorly soluble diformazan violet to blue pigment having a broad spectral absorption band ({lambda}{sub max}=552 nm). The reaction of BT{sup 2+} with the hydrated electron proceeds by rapid reduction of BT{sup 2+} followed by protonation at the nitrogen closest to the unsubstituted phenyl group, via the two intermediate tetrazolinyl radicals shared by the ditetrazole ring nitrogens. The effect of solution pH, N{sub 2}O saturation, and the presence of the reducing agent dextrose are examined. The system serves as a radiochromic sensor and a dosimeter of ionizing radiations. Solutions of 5 mmol l{sup -1} BT{sup 2+} at pH 7.3 serve as dosimeters over an absorbed-dose range of approximately 0.2-6 kGy (dearated, with a range of 1-8 mmol l{sup -1} dextrose) and of about ...

2002-04-01

462

Post-machining thermal treatment after surface finishing of hardened steels: Kinetics of XRD line width reduction and improvement in rolling contact lifetime under mixed friction conditions  

Energy Technology Data Exchange (ETDEWEB)

Hard surface finishing represents the final manufacturing step for functional areas of machine elements in state-of-the-art production. Raceways of rolling bearing rings are ground and honed to the required low roughness. Plastic deformation is restricted to a narrow edge zone of the hardened steel. Reheating of the machined components below the martensite tempering or bainite transformation temperature results in a marked decrease of the XRD line width on the surface. The investigated samples are made of through-hardened standard bearing steel 100Cr6 (international denotation: SAE 52100). On the basis of a material model that explains the effect as a complex diffusion process of dislocational carbon segregation, i.e. static strain aging, the measured kinetics of the XRD line width reduction is simulated by an Arrhenius-type equation, which describes the rate-controlling reaction step of temper carbide dissolution. The formation of a small white-etching surface ...

2008-07-01

463

Pilot-scale testing of pyrolysis for the volume reduction of organic waste  

Energy Technology Data Exchange (ETDEWEB)

Pilot-scale pyrolysis units have been in operation since 1980 to test the efficiency of thermal treatment of transuranic (TRU) solid waste to retrieve the TRUs and to reduce the volume of wastes such as spent solvent, spent resin, and others. These wastes are generated by reprocessing, fuel production, and utilities. NUKEM has developed a criticality-safe, ring-slab reactor to decompose solid TRU waste. The plant processes 25 kg/h with a polyvinyl chloride content up to 70%. The overall throughput (inactive) up to the spring of 1982 was 2000 kg. The decontamination factor for the reactor itself is 1000. The liquid wastes, mainly spent solvent, are cracked under nitrogen at 400 to 700/sup 0/C in a reactor that is filled by a packed bed kept in motion by a specially designed agitator. This unit was built for 15 kg/h water equivalent evaporation. Up to 1982 the unit processed 2000 kg of spent solvent (simulated) overall. The decontamination factor is similar to the ...

1982-11-01

464

Pilot-scale testing of pyrolysis for the volume reduction of organic waste  

International Nuclear Information System (INIS)

Pilot-scale pyrolysis units have been in operation since 1980 to test the efficiency of thermal treatment of transuranic (TRU) solid waste to retrieve the TRUs and to reduce the volume of wastes such as spent solvent, spent resin, and others. These wastes are generated by reprocessing, fuel production, and utilities. NUKEM has developed a criticality-safe, ring-slab reactor to decompose solid TRU waste. The plant processes 25 kg/h with a polyvinyl chloride content up to 70%. The overall throughput (inactive) up to the spring of 1982 was 2000 kg. The decontamination factor for the reactor itself is 1000. The liquid wastes, mainly spent solvent, are cracked under nitrogen at 400 to 700"0C in a reactor that is filled by a packed bed kept in motion by a specially designed agitator. This unit was built for 15 kg/h water equivalent evaporation. Up to 1982 the unit processed 2000 kg of spent solvent (simulated) overall. The decontamination factor is similar to the figures ...

465

Particle physics -- Future directions  

Energy Technology Data Exchange (ETDEWEB)

Wonderful opportunities await particle physics over the next decade, with the coming of the Large Hadron Collider at CERN to explore the 1-TeV scale (extending efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry breaking) and many initiatives to develop our understanding of the problem of identity: what makes a neutrino a neutrino and a top quark a top quark. Here I have in mind the work of the B factories and the Tevatron collider on CP violation and the weak interactions of the b quark; the wonderfully sensitive experiments at Brookhaven, CERN, Fermilab, and Frascati on CP violation and rare decays of kaons; the prospect of definitive accelerator experiments on neutrino oscillations and the nature of the neutrinos; and a host of new experiments on the sensitivity frontier. We might even learn to read experiment for clues about the dimensionality of spacetime. If we are inventive enough, we may be able to follow this rich menu with the physics opportunities ...

2001-11-29

466

Ozone production at the National Synchrotron Light Source  

International Nuclear Information System (INIS)

Ozone production by synchrotron radiation as a function of power density in air was investigated using a white beam at the BNL National Synchrotron Light Source (NSLS) x-ray ring. Power densities were calculated from the energy spectrum at 2.52 GeV. Ozone concentrations in small beam pipes were measured for power densities between I = 10"1"2 and 10"1"5 eV . cm"-"3 . sec"-"1. The measured ozone half-life was 37 +- 2 min. The measured G-value was 2.69 +- 0.14 mol/100 eV and the ozone destruction factor k was less than 7 x 10"-"1"9 cm"3 . eV"-"1. The random uncertainties stated are approximately one standard error. The large departure of the values for G and k from previous values suggest that some undiscovered systematic error may exist in the experiment. Ozone concentration in excess of the 0.1 ppM ACGIH TLV can be generated in the experimental hutches but can readily be controlled. Industrial hygiene aspects of operation and possible control measures will be ...

1998-09-20

467

Ozone production at NSLS  

International Nuclear Information System (INIS)

Ozone production by synchrotron radiation as a function of power density in air was investigated using a white beam at the BNL National Synchrotron Light Source (NSLS) x-ray ring. Power densities were calculated from the energy spectrum at 2.52 GeV. Ozone concentrations in small beam pipes were measured for power densities between I = 10/sup 12/ and 10/sup 15/ eV/sup . /cm/sup -3 . /sec/sup -1/. The measured ozone half-life was 37+-2 min. The measured G-value was 2.69+-0.14 mol/100 eV and the ozone destruction factor k was less than 5 x 10/sup -19/cm/sup 3//eV. The random uncertainties stated are approximately one standard error. The large departure of the values for G and k from previous values suggest that some undiscovered systematic error may exist in the experiment. Ozone concentration in excess of the 0.1 ppm ACGIH TLV can be generated in the experimental hutches but can readily be controlled. Industrial hygiene aspects of operation and possible control ...

468

Novel non-discoid chiral copper(II)-salen type [N2O2] donor Schiff base complexes with a cyclohexane diamine spacer: synthesis, electrochemistry, columnar mesomorphism and DFT study  

British Library Electronic Table of Contents (United Kingdom)

A series of new non-discoid chiral copper(ii)-salen type complexes, [Cu((4-CnH2n+1O)2salen)], n = 14, 16, 18 and salen = N,N'-cyclohexane bis (salicylideneiminato), containing 4-substituted alkoxy tails in the side aromatic rings and a cyclohexane spacer, have been prepared and their mesogenic properties investigated. The compounds were characterised by Fourier transform infra-red spectroscopy, 1H and 13C nuclear magnetic resonance spectroscopy, UV-vis spectroscopy and fast atom bombardment mass spectrometry. Mesomorphic properties of these compounds were studied by polarising optical microscopy, differential scanning calorimetry and X-ray diffraction (XRD). The ligands are non-mesogenic but the complexes exhibited enantiotropic rectangular columnar mesophases (Colr) with extended temperat...

2011-01-01

469

Netware-Specific Network Security.  

Science.gov (United States)

This paper focuses on practical and cost-effective NetWare-specific approaches to information systems and computer security. A series of real world experiences is presented that illustrate fundamental information systems and security concepts. A NetWare network is a client-server network which uses a file server to share files while client workstations access the file server via some network typology (usually ethernet or token ring). Passwords are used to authenticate users; thus, password protection is a cornerstone of network security. Passwords can be encrypted, but this feature can be disabled. The bindery, which stores information about users, groups, and printers, is critical to the network and must be backed up. Trade secrets can be hidden from users by restructuring menus. Login scripts should be protected and not used for security purposes. Guest account access should be restricted or removed. Finally, the "security.exe" program can be used to find ...

1994-12-01

470

Metallic implants and exposure to radiofrequency radiation  

International Nuclear Information System (INIS)

There is increasing use of radiofrequency radiation (RFR) in industry for communications, welding, security, radio, medicine, navigation etc. It has been recognised for some years that RFR may interact with cardiac pacemakers and steps have been taken to prevent this interference. It is less well recognised that other metallic implants may also act as antennas in an RFR field and possibly cause adverse health effects by heating local tissues. There are a large and increasing number of implants having metal components which may be found in RFR workers. These implants include artificial joints, rods and plates used in orthopaedics, rings in heart valves, wires in sutures, bionic ears, subcutaneous infusion systems and (external) transdermal drug delivery patches"1. The physician concerned with job placement of such persons requires information on the likelihood of an implant interacting with RFR so as to impair health. The following outlines the approach developed in ...

471

IC 4767 (the X-galaxy) - the missing link for understanding galaxies with peanut-shaped bulges?  

International Nuclear Information System (INIS)

Photometric and kinematic observations of the peculiar S0 galaxy IC 4767, the X-galaxy, are presented. At various intensities the bulge of this galaxy looks like a normal spheroidal system with elliptical isophotes, a well-defined rectangle, and a peanut-shaped or X-shaped structure with components aligned at oblique angles to the major axis. The observations reveal a rapidly rotating inner disk of gas and dust which is nearly aligned with the major axis. The presence of gaseous emission alone suggests an accretion event. The stars in the outer regions of the X-component are rotating nearly as rapidly as the gas in the main disk, indicating that they are in relatively circular orbits. The five most prominent peanut-shaped bulges all have several nearby companions, evidence that the peanut deformity is due to interaction between galaxies. An analogy with the formation mechanism proposed for polar-ring galaxies suggests how an X-shaped component could develop from ...

1988-01-01

472

Highly specific antiserum for arginine vasopressin  

International Nuclear Information System (INIS)

A high sensitivity (titer 60-150,000) radioimmunoassay for arginine vasopressin (AVP) has been developed using synthetic AVP as antigen and standard. The specificity of the antiserum has been characterized in detail by measuring the relative binding affinities of 29 analogs and fragments of AVP. In general, single amino acid substitution or deletion in the AVP molecule caused a reduction in binding to the antiserum; binding was further impaired for analogs which had multiple substitutions. ''Ring'' and ''tail'' fragments of the neurohypophysial hormones did not bind to the antiserum, and the only analog which the antiserum could not differentiate from AVP was deamino-AVP. More specifically, the antiserum exhibited the following properties: position 1, no requirement for a position charge at "1/_2 Cys; positions 2 and 3, requirements for #pi#-#pi# interacting pair of aromatic side chains and for Tyr at position 2; position 4, requirement for Gln (>Thr > Val); ...

473

High temperature friction and wear characteristics of superalloys X-750 and 188 for use in low heat rejection engines  

Energy Technology Data Exchange (ETDEWEB)

Engineering materials for use in low heat rejection engines are required to function under stringent tribological conditions. Severe wear damage and high friction between the components of the tribosystem limit the number of potential materials suitable for such application conditions. The superalloys X-750 and 188 are composed of alloying elements that not only promote a high mechanical and chemical stability but may also result in a reduced wear rate and friction coefficient at elevated temperatures. As a part of the DOE-ECUT Tribology program at Argonne, the present study was undertaken to evaluate the tribological characteristics of these alloys that will also be utilized as the substrates for ion beam deposited lubricous coatings. A wear test rig that crudely simulated the sliding conditions between a piston ring and a cylinder liner in an operating engine was utilized for friction and wear studies. The test results indicated that the wear and friction ...

1988-01-01

474

Gulf of Mexico petroleum accumulations a review of recent studies on sources of the oils, modes of source rock maturation and oil migration  

Energy Technology Data Exchange (ETDEWEB)

Recent organic geochemical studies differ radically in their interpretation of the origin of the Gulf coast oils. However all studies since (and including) Thompson, et al. 1989, emphasize the considerable geographic variation in genetic oil types and are in generalized agreement as to the genetic oil types present and their spatial and stratigraphic relationships. In particular it is accepted that the Gulf rim (both north and south) is encircled by a ring of Mesozoic carbonate-sourced oils and that there is also at least one major deep water trend of carbonate-sourced oils in the northern Gulf. It is also generally agreed that many of the Gulf rim oils are of Oxfordian-Kimmeridgian age, though some, like the Sunniland oils of Florida, are of lower Cretaceous origin. Major disagreement still occurs over the sources of the Louisiana offshore oils and onshore Wilcox reservoired oils. One {open_quotes}school of thought{close_quotes} assigns all these oils to Mesozoic ...

1996-09-01

475

Full scale testing of wind turbine blade to failure - flapwise loading  

Energy Technology Data Exchange (ETDEWEB)

A 25m wind turbine blade was tested to failure when subjected to a flapwise load. With the test setup, it was possible to test the blade to failure at three diffe-rent locations. The objective of these tests is to learn about how a wind turbine blade fails when exposed to a large flapwise load and how failures propagate. The report shows also results from ultra sonic scan of the surface of the blade and it is seen to be very useful for the detection of defects, especially in the layer between the skin laminate and the load carrying main spar. Acoustic emission was successfully used as sensor for the detection of damages in the blade during the test. The report contains measurements of the total deflection of the blade, the local deflection of the skin and the load carrying main spar and also measurement of strain all as a function of the applied load and up to failure of the blade. The 'post mortem' analysis and description of how the damages propagate ...

2004-06-01

476

Free electron laser facilities employing a 150-MeV linac injector for Saga synchrotron light source  

International Nuclear Information System (INIS)

Free electron laser (FEL) facilities as the FELI FEL Facility are proposed, for which a 150-MeV linac type injector for a Saga synchrotron light source (SLS) is employed in FEL mode. The linac has two operating modes; short macropulse mode a 1 #mu#s at 150 MeV for injection to a 1 - 1.3-GeV third generation type storage ring and long macropulse mode of 12 #mu#s at 100 MeV for four FEL Facilities. The macropulse beam consists of a train of several ps, 0.6 nC microbunches (peak current 100 A) repeating at 89.25 MHz. We are aiming to supply high power level photon beams covering an attractive wavelength range from 0.05 nm (25 keV) to 200 #mu#m (0.006 eV) for scientific researches, bio-medical and industrial applications, using the Saga third generation type SLS with a superconducting wiggler and the proposed four FEL Facilities. (author)

1999-12-01

477

Free electron laser and accelerator  

International Nuclear Information System (INIS)

The present report addresses several aspects of the free electron laser (FEL) and accelerator, including their features, potentials, mechanisms, beams emitted from undulator, FEL produced by helical mangnetic field, major problems with FEL, etc. In FEL, relativistic electron beams interact with an electromagnetic field with periodically changing intensity to produce coherent electromagnetic waves with variable wavelength. The capability of varying its wavelength represents the greatest advantage over conventional lasers. Any periodic magnetic field can serve as a wiggler. A wiggler can be used both in an amplifier and oscillator. A periodic magnetic field used may be either of a parallel type or of a helical type. The polarization of emitted beams depends on the shape of the magnet regardless of whether its field is parallel or helical. An equation is derived in the report which expresses the wavelength of an electromagnetic wave produced by an undulator. An analysis is made of FEL ...

1988-08-01

478

Effects of extreme pressure additive chemistry on rolling element bearing surface durability  

Energy Technology Data Exchange (ETDEWEB)

Lubricant additives have been known to affect rolling element bearing surface durability for many years. Tapered roller bearings were used in fatigue testing of lubricants formulated with gear oil type additive systems. These systems have sulfur- and phosphoruscontaining compounds used for gear protection as well as bearing lubrication. Several variations of a commercially available base additive formulation were tested having modified sulfur components. The variations represent a range of ''active'' extreme pressure (EP) chemistries. The bearing fatigue test results were compared with respect to EP formulation and test conditions. Inner ring near-surface material in selected test bearings was evaluated on two scales: the micrometer scale using optical metallography and the nanometer scale using transmission electron microscopy (TEM). Focused-ion beam (FIB) techniques were used for TEM specimen preparation. Imaging and chemical ...

2007-08-01

479

Effect of surface treatemnts on stress corrosion cracking of alloy 800 in alkaline solutions. Alloy 800 no alkaline yoekichu no ouryoku fushoku ware ni oyobosu hyomenkako no eikyo  

Energy Technology Data Exchange (ETDEWEB)

Effect of the coverage of shot peening, the surface roughness and shot shape, etc. on the stress corrosion cracking (SCC) of Alloy 800 in alkaline solutions was studied. Alloy 800 specimens were cracked in boiling alkaline solutions at the potntial range of {minus} 100 to 0mV in the boiling 50%NaOH+0.3%SiO {sub 2} solution. U bend specimens were tested under the polarized condition at the controlled potential to 0mV, showing that shot peened specimens cracked more easily. Tests of specimens with the same hardness showed that specimens hardened by cold working showed the higher susceptivity than that of surface hardened specimens. In these connections, U bend specimens of higher shot peened coverage were cracked at conditions of 593K and 10%NaOH solution. O-ring specimens of smaller stress level did not show any cracks independent of surface treatments. 8 refs., 9 figs., 5 tabs.

1990-03-15

480

Effect of processing on pirimiphos-methyl residues in stored peanuts  

International Nuclear Information System (INIS)

Peanut grains (1500g) were placed in a jute sack which was sprayed with "1"4C- pirimiphos-methyl [0-2-diethylamino-6-methylpyrimidin-4-yl-O, O-dimethylphosphorothiate, "1"4C-labelled in the 2-position of the pyrimidine ring]; total dose 5.55 MBq + 22.5 mg cold insecticide. As in practice, the sack was stored under local conditions for 36 weeks. The grain was crushed, dried at 50 deg. C for 2 hours and soxhlet extracted with chloroform-methanol (1:1). The crude oil was then subjected to sequential processes of alkali treatment, bleaching and deodorization. The initial residue concentration in the crude oil (5.66 ppm) was reduced to 4.50 ppm through alkali treatment and declined further to 3.78 ppm after bleaching. Deodorization removed a substantial amount of "1"4C-residues leaving 1.35 ppm in the refined oil. It may be concluded that simulated commercial processing of crude oil were capable of removing 76% of pirimiphos-methyl and/or products. The most efficient ...

1995-08-01

481

Effect of crevice environment PH on corrosion damage of horizontal steam generator tubes  

Energy Technology Data Exchange (ETDEWEB)

In support of a project on lifetime calculation experiments were carried out to evaluate the resistance to environmentally assisted cracking (EAC) of steam generator tubes during operation. Estimations of the incubation period for crack initiation and the threshold K value, K{sup Iscc}, and the crack growth rate were made to predict evolution of damage in tube walls. The paper summarizes results of experiments of C ring specimen for the initiation testing and results of SENT (single edge notch tensile) specimen for the crack growth rate (CGR) testing. The specimens were exposed to concentrated environments at elevated temperatures simulating crevice environments in secondary side crevices in horizontal steam generators. The results show that the material of SG tubes is sensitive to transgranular environmentally assisted cracking in the three basic concentrated environments used, alkaline, neutral and acid. The most corrosive medium was the acid environment. The ...

2002-07-01

482

Effect of crevice environment PH on corrosion damage of horizontal steam generator tubes  

International Nuclear Information System (INIS)

In support of a project on lifetime calculation experiments were carried out to evaluate the resistance to environmentally assisted cracking (EAC) of steam generator tubes during operation. Estimations of the incubation period for crack initiation and the threshold K value, K"I"s"c"c, and the crack growth rate were made to predict evolution of damage in tube walls. The paper summarizes results of experiments of C ring specimen for the initiation testing and results of SENT (single edge notch tensile) specimen for the crack growth rate (CGR) testing. The specimens were exposed to concentrated environments at elevated temperatures simulating crevice environments in secondary side crevices in horizontal steam generators. The results show that the material of SG tubes is sensitive to transgranular environmentally assisted cracking in the three basic concentrated environments used, alkaline, neutral and acid. The most corrosive medium was the acid environment. The crack ...

2002-05-05

483

Dynamical evolution driven by bars and interactions Input from numerical simulations  

CERN Document Server

We discuss the evolution of a disc galaxy due to the formation of a bar and, subsequently, a peanut. After the formation stage there is still considerable evolution, albeit slower. In purely stellar cases the pattern speed of the bar decreases with time, while its amplitude grows. However, if a considerable gaseous component is present in the disc, the pattern speed may increase with time, while the bar strength may decrease. In some cases the gas can be brought sufficiently close to the center to create a strong central concentration, which, in turn, may modify the properties of the bar. More violent evolution can take place during interactions, so that some disc substructures can be either formed or destroyed in a time scale which is small compared to a Hubble time. These include spirals, bars, bridges, tails, rings, thick discs and bulges. In some cases interactions may lead to mergings. We briefly review comparisons of the properties of merger remnants with ...

2002-01-01

484

Device for removing drilling fines from a well head  

Energy Technology Data Exchange (ETDEWEB)

The device for removing drilling fines from the well head includes a support disk encompassing the sucker rod of the drilling machine with frame made in the form of a dish with inner conical surface, and overturned truncated cone located in the dish of the support disk with the formation between them of a ring guide slit. In order to improve the effectiveness of removing the drilling fines and convenience of operation by excluding heavy manual auxiliary operations to clean the well head and to move the device from one well to another, it is equipped with a mechanism for suspension with a drive. The inner conical surface of the dish is equipped with slide blocks, while the overturned truncated cone is equipped with projections. The suspension mechanism is made in the form of a hydrocylinder and two pairs of levers connected in pairs by means of hinges. The hinges of each pair of levers are connected to the hydrocylinder, and the levers are hinged to the machine ...

1982-01-01

485

Development of advanced residential cooktop burner with low NO/sub x/ emissions. Annual report Feb 82-Jan 83  

Science.gov (United States)

This report describes the results of work conducted during February 1982 - January 1983. A literature search was initiated to identify the state-of-the-art of NOx (NO + NO/sub 2/) reduction technologies, including NOx measurement methodologies, air infiltration and ventilation trends, the impact of NOx (NO/sub 2/) emissions on health, and air quality standards. As a result of the literature search NOx (NO/sub 2/) reduction goals were established for the project and technologies to achieve these goals identified. This report also covers the development of a prototype burner which examined flue gas recirculation, burner designs, secondary air baffling and flame inserts as potential technologies to reduce NOx (NO/sub 2/). Because of their potential for NOx (NO/sub 2/) reduction shown by initial experiments, an in-depth analysis of ring insert configurations was conducted. These results, along with other technological experiments, are presented in this report.

1983-02-28

486

Crystalline beam ground state  

Energy Technology Data Exchange (ETDEWEB)

In order to employ molecular dynamics (MD) methods, commonly used in condensed matter physics, we have derived the equations of motion for a beam of charged particles in the rotating rest frame of the reference particle. We include in the formalism that the particles are confined by the guiding and focusing magnetic fields, and that they are confined in a conducting vacuum pipe while interacting with each other via a Coulomb force. Numerical simulations using MD methods has been performed to obtain the equilibrium crystalline beam structure. The effect of the shearing force, centrifugal force, and azimuthal variation of the focusing strength are investigated. It is found that a constant gradient storage ring can not give a crystalline beam, but that an alternating-gradient (AG) structure can. In such a machine the ground state is, except for one-dimensional (1-D) crystals, time dependent. The ground state is a zero entropy state, despite the time-dependent, ...

1993-06-11

487

Correlated charge-changing ion-atom collisions. Progress report, February 16, 1990--February 15, 1993  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the progress and accomplishments in accelerator atomic physics research supported by DOE grant DE-FG02-87ER13778 from February 16, 1990 through February 15, 1993. This work involves the experimental investigation of atomic interactions in collisions of charged projectiles with neutral targets or electrons, with particular emphasis on two-electron interactions and electron-correlation effects. The processes studied are of interest both from fundamental and applied points of view. In the latter case, results are obtained which are relevant to the understanding of laboratory and astrophysical plasmas, highly-excited (Rydberg) and continuum states of atoms and ions, atomic structure effects, the interaction of ions with surfaces, and the development of heavy-ion storage-rings. The results obtained have provided the basis for several M.A. thesis projects at Western Michigan and several Ph.D. dissertation projects are currently underway. Summaries ...

1993-02-01

488

Cold gas & mergers: fundamental difference in HI properties of different types of radio galaxies?  

CERN Document Server

We present results of a study of large-scale neutral hydrogen (HI) gas in nearby radio galaxies. We find that the early-type host galaxies of different types of radio sources (compact, FR-I and FR-II) appear to contain fundamentally different large-scale HI properties: enormous regular rotating disks and rings are present around the host galaxies of a significant fraction of low power compact radio sources, while no large-scale HI is detected in low power, edge-darkened FR-I radio galaxies. Preliminary results of a study of nearby powerful, edge-brightened FR-II radio galaxies show that these systems generally contain significant amounts of large-scale HI, often distributed in tail- or bridge-like structures, indicative of a recent galaxy merger or collision. Our results suggest that different types of radio galaxies may have a different formation history, which could be related to a difference in the triggering mechanism of the radio source. If confirmed by larger ...

2008-01-01

489

Chemo-enzymatic epoxidation of olefins by carboxylic acid esters and hydrogen peroxide  

Energy Technology Data Exchange (ETDEWEB)

Ethylen and, recently, butadiene can be epoxidized directly with oxygen and for the epoxidation of propylene, the use of heterogeneous transition metals and organic peroxides (Halcon-Process) is the major player. But, beside from those notable exceptions, all other epoxidations, including large ones like the epoxidation of plant oils as PVC-stabilizers (about 200.000 t/year), are carried out with peroxy acids. Because mcpba is far to expensive for most applications, short chain peracids like peracetic acid are used. Being much less stable than mcpba and thus risky handled in large amounts and high concentrations, these peroxy acids were preferably prepared in-situ. However, conventional in-situ formation of peracids has the serious drawback, that a strong acid is necessary to catalyze peroxy acid formation from the carboxylic acid and hydrogen peroxide. The presence of a strong acid in the reaction mixture often results in decreased selectivity because of the formation of undesired ...

1998-12-31

490

Characterisation of polynuclear aromatic sulfur-heterocycles in a coal extract by GC/MS  

Energy Technology Data Exchange (ETDEWEB)

Polynuclear aromatic sulphur heterocycles (PASHs) were isolated from a coal extract by two-step separation method using silica gel column chromatography and ligand exchanges thin layer chromatography (PdCl{sub 2}/SiO{sub 2}). The subfraction was examined by capillary column gas chromatography with flame ionization detector and flame photometric detector and gas chromatography - mass spectrometry. Identification was accomplished by comparison of chromatographic retention indices and mass spectra of compounds with those reported in the literature. It was found that the principal structures of the sulphur-containing fraction of Guiding coal extract have 3-4 aromatic rings. Dibenzothiophene, C{sub 1} - C{sub 3} alkylated dibenzothiophenes, benzonaphthothiophene and its alkylated derivatives were the main compounds. Only a few other polynuclear sulfur heterocycles were detected. No benzothiophene and its derivatives were presented. 8 refs., 2 figs., 3 tabs.

1994-06-01

491

BWNT assessment of TRAC/PF1-MOD2  

International Nuclear Information System (INIS)

The TRAC/PFI-MOD2 Version 5.3 code was assessed against six FLECHT-SEASET forced reflood tests (31504, 31203, 31302, 31701, 34209, and 31922) and two cylindrical core test facility (CCTF) tests [C1-19 and C2-6]. The objective of this study was to evaluate the clad thermal response predictive capabilities of the code with the newly added reflood model under large-break loss-of-coolant accident (LOCA) conditions in a pressurized water reactor (PWR). The TRAC model for the FLECHT-SEASET test facility was developed from a RELAP5 model. The test section was modeled using a vessel component with 23 axial levels, 1 radial ring, and 1 azimuthal cell. Test inlet and exit conditions were modeled using fill and break components, respectively. The measured lower and upper plenum test conditions were input to the model. The electrically heated rod was modeled using a rod component with 22 axial mesh points. The axial boundary of each mesh point coincided with a fluid cell ...

1993-11-14

492

Aspects of Stability Related to the Colliding Beam Fusion = Reactor  

Science.gov (United States)

Recent experiments with TFTR, D-III-D and JET involving the injection and trapping of low density beams of high energy large orbit ions indicate that large orbit non-adiabatic ions slow down and diffuse classically in the presence of anomalous fluctuations and transport of adiabatic majority particles. Accordingly, we consider conceptual fusion reactors(N. Rostoker, M.W. Binderbauer and H.J. Monkhorst, Science) 278, 1419 (1997). based on classical confinement of fuel ions and fusion products(M.W. Binderbauer and N. Rostoker, J. Plasma Phys.) 56, 451 (1996).. The magnetic confinement geometry of the proposed designs is a Field Reversed Configuration. A survey of experimental results on instabilities and their characteristics as related to these reactor concepts is presented. Particular focus will be given to long wavelength (as compared to gyro-radius) and low frequency (?<< c/r_o, r_o=3D major radius of annular current ring) instabilities as they are most ...

1998-11-01

493

Analysis of high turbulence combustion in a direct-injection diesel engine with high squish combustion chamber; CFD ni yoru ko squish nenshoshitsunai koranryu diesel nensho no kaiseki  

Energy Technology Data Exchange (ETDEWEB)

Simultaneous reduction of NO{sub x} and particulate emissions in a direct-injection diesel engine has been realized experimentally with a high squish combustion chamber. The purpose of this study is to investigate the effects of high squish combustion chamber on combustion process in detail. Engine CFD code FREC was used for the analysis. The results show the followings. (1) Compared with standard toroidal chamber, high squish chamber generates high turbulence due to strong squish and large expansion flow is caused in the cavity. (2) Rich and high-turbulence combustion, which forms ring area in the cavity under squish lip, continues during the combustion. (3) The high squish combustion chamber keeps fuel long in the cavity and less hid spreads out to the cold clearance volume. (4) For the condition of retarded injection timing, the effect of high squish is mainly observed at initial combustion and high swirl is more effective at diffusion combustion. (author)

1999-08-25

494

Acidic and neutral polar NSO compounds in Smackover oils of different thermal maturity revealed by electrospray high field Fourier transform ion cyclotron resonance mass spectrometry  

Energy Technology Data Exchange (ETDEWEB)

Negative ion electrospray ionization (ESI) coupled with high field Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) allows for the direct detection of acidic NSO compounds in petroleum. The technique requires no chromatographic separation, is able to distinguish 18 different compound classes (e.g., neutral nitrogen, carboxylic acids and oxygenates), and can identify {approx}14,000 distinct masses by ultra-high mass resolution and mass accuracy. We previously studied three crude oils from different geological origins [Organic Geochemistry 33 (2002b) 743-759]. Here, we expand our research by comparing two source-equivalent Smackover oils of different levels of thermal maturity. We observe clear differences in the distribution of NSO compound classes, types (number of rings plus double bonds within a class), and number of alkyl carbons. With increasing thermal stress, the relative amount of sulfur and oxygen containing compounds decreases, ...

2004-07-01