WorldWideScience
1

X-ray photoelectron spectroscopy and x-ray excited Auger spectroscopy studies of manganese thiophosphate intercalated with sodium ions  

Science.gov (United States)

Polycrystalline powders of Na{sub 2x}Mn{sub 1-x}PS{sub 3} have been synthesized from layered MnPS{sub 3} material by successive ion-exchange intercalation of potassium and sodium ions. Their x-ray photoelectron spectroscopy (XPS) and x-ray excited Auger spectroscopy spectra have been measured at room temperature using Mg K{alpha} (1253.6 eV) x-ray source. In particular, the Mn, P, and S 2p and Na 1s and 2p core-level regions and the Na Auger KL{sub 23}L{sub 23} transition have been investigated. All the analyzed XPS core-level spectra display a single-peak structure, suggesting the absence of nonequivalent atoms of Na, Mn, P, and S. The manganese XPS spectrum shows, as observed in MnPS{sub 3} and in its cesium and potassium intercalation compounds, typical shake-up satellites, suggesting that the Mn-S bond is yet mainly ionic in nature. The comparison with the ...

2008-12-15

2

Rubidium 5"2P fine-structure transitions induced by collisions with potassium and caesium atoms  

International Nuclear Information System (INIS)

A diode-laser fluorescence experiment was performed in order to study fine-structure transitions between 5"2P states of rubidium atoms colliding with ground-state potassium or caesium atoms. The Rb(5"2P_3_/_2) state was optically excited and the intensity ratio of sensitized to direct fluorescence was measured. (author).

3

Electron impact excitation of lithium-like iron  

Energy Technology Data Exchange (ETDEWEB)

Calculations of total and angle-differential excitation cross sections for the electron impact excitation of lithium-like iron were performed with the R-matrix formulation. The alignments of the excited states 1s{sup 2}np {sup 2}P{sub 3/2} are also presented for n=3 and 4 along with the angular photon distribution from these states to the ground state. Relativistic effects were included in the present calculations by the Breit-Pauli Hamiltonian.

1996-05-01

4

Calculation of the contributions from high-n dielectronic satellites to the K{alpha} resonance line in helium-like iron  

Energy Technology Data Exchange (ETDEWEB)

A simplified relativistic configuration interaction method is used to study the dielectronic satellite transition processes. In this method, the infinite resonant doubly excited states can be calculated, and furthermore, the whole high-n dielectronic satellite transition processes can be treated conveniently by interpolation (rather than extrapolation) in the frame of quantum defect theory. As an example, we calculate the contributions from high-n dielectronic satellites to the K{alpha} resonance line in helium-like iron, and the results are in good agreement with the experimental measurements. (orig.) 39 refs.

1999-02-01

5

Excitation cross sections of Cd"+ ions for the upper and lower states of the Cd II 441.6-nm laser line by electron impact  

International Nuclear Information System (INIS)

The excitation cross sections by electron impact from the Cd II ground state to the laser upper state 5s_2 _2D/sub 5/2/ (Beutler state) and the laser lower state 5p _2P/sub 3/2/ (resonance state) have been measured by using a crossed-beam method of electrons and Cd"+ ions and a photon-counting method. The electron-energy region investigated was from the threshold energy (5.8 eV) for the excitation of the 5p _2P/sub 3/2/ state to 20 eV. It has been shown that the excitation cross section for the ionic Beutler state 5s_2 _2D/sub 5/2/ is of the order of 10"-_1_5 cm_2 and has a sharp peak near the threshold energy for the excitation. The excitation cross section for the resonance state 5p _2P/sub 3/2/ has also been of the order of 10"-_1_5 cm_2 and has a ...

6

Carvedilol targets human K2P3.1 (TASK1) K+ leak channels  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE Human K2P3.1 (TASK1) channels represent potential targets for pharmacological management of atrial fibrillation. K2P channels control excitability by stabilizing membrane potential and by expediting repolarization. In the heart, inhibition of K2P currents by class III antiarrhythmic drugs results in action potential prolongation and suppression of electrical automaticity. Carvedilol exerts antiarrhythmic activity and suppresses atrial fibrillation following cardiac surgery or cardioversion. The objective of this study was to investigate acute effects of carvedilol on human K2P3.1 (hK2P3.1) channels. EXPERIMENTAL APPROACH Two-electrode voltage clamp and whole-cell patch clamp electrophysiology was used to record ...

2011-01-01

7

Cross sections for electron scattering by atomic potassium  

International Nuclear Information System (INIS)

Electron elastic and collisional excitation cross sections from the ground state of potassium are calculated using the noniterative integral-equation method of Henry, Rountree, and Smith [Comput. Phys. Commun. 23, 233 (1981)] in the electron energy range 4#<=#E#<=#200 eV. Configuration-interaction target wave functions that take account of correlation and polarization effects are used to represent the ground state and the six lowest excited states 4p "2P degree, 5s "2S, 3d "2D, 5p "2P degree, 4d "2D, and 6s "2S. Elastic and discrete excitation cross sections are obtained in a seven-state close-coupling (7CC) approximation. The 7CC elastic and excitation cross sections are compared and contrasted. Near threshold the elastic cross section dominates the resonance, 4s "2S#->#4p ...

8

SRS conversion of XeCl laser radiation into shifted Stokes components  

International Nuclear Information System (INIS)

An experimental study and a theoretical simulation were made of stimulated Raman scattering (SRS) conversion into shifted components. It was found that there were optimal values of the pressure and focal distance for conversion into the first 'blue' satellite of the first Stokes component. A study was made of the spatial and temporal dynamics of SRS conversion, which took into account generation of the shifted components. It was demonstrated theoretically and experimentally that the satellite intensity could be enhanced significantly by additional electron-collision excitation of the vibrational levels in the conversion medium or by the application of pairs of pump pulses. The maximum efficiency of conversion to the first 'blue' satellite of the first Stokes component was 10% and the satellite intensity reached one-third of the intensity of the main Stokes line. (nonlinear optical ...

1998-01-31

9

Fine structure excitation transfer between the potassium 4"2P states induced by collisions with caesium atoms  

International Nuclear Information System (INIS)

Applying diode-laser resonant fluorescence method, the cross sections for the excitation energy transfer of the collisional process K"*(4"2P_1_/_2)+Cs(6"2S_1_/_2)#reversible#K"*(4"2P_3_/_2)+Cs(6"2S_1_/_2) have been measured. The values we have obtained are #sigma#(1/2#->#3/2)=77 A"2 and #sigma#(3/2#->#1/2)=48 A"2. These results complete the sequence of data for the fine-structure mixing of the first-resonance states of alkali atoms colliding with the ground-state caesium atoms. (orig.).

10

Time-resolved Fourier transform emission spectroscopy of A2P-X2+ infrared transition of the CN radical  

British Library Electronic Table of Contents (United Kingdom)

The A2P-X2+Dv=-3 bands of the 12C14N radical have been observed by time-resolved Fourier transform spectroscopy in the 1850-3100cm-1 region with a wavenumber resolution of 0.025cm-1. The radical was produced in a pulsed positive column discharge in a cyanogene and helium mixture. Seven bands of v=0-3, 1-4, 2-5, 3-6, 4-7, 5-8, and 6-9 were analyzed to give the molecular constants of each state by least-squares fitting of 801 lines. The pulsed discharge was found to be efficient for production of CN in the excited A2P state. The vibrational excitation temperature was determined to be 6680+-835K and 6757+-534K for the A2P and X2+ states, respectively. The population of the A2P was found to be 4% of that of the X2+ state in the time after turning off the discharge.

2008-01-01

11

Electron impact excitation cross sections in F-like selenium  

Science.gov (United States)

Cross sections for excitation induced by electron collision between low-lying 1s{sup 2}2s{sup 2}2p{sup 5} and 1s{sup 2}2s2p{sup 6} states of f-like selenium and from these states to singly excited states with the excited electron occupying the M shell have been calculated by relativistic distorted-wave Born procedures. The GRASP{sup 2} code was used for the atomic structure calculations. The continuum orbitals for the construction of continuum states were computed in the distorted-wave approximation, in which the distorted-wave potential used was the spherically averaged potential of the nucleus plus the potential of the bound electrons of the bound state. The cross sections for excitations were computed first by a 233-level multiconfiguration Dirac-Fock (MCDF) configuration expansion and then by a 279-level MCDF ...

1998-09-01

12

Absolute cross sections for near-threshold electron-impact excitation of the 2s"2S#->#2p"2P transition in C"3"+  

International Nuclear Information System (INIS)

Absolute total cross sections for electron-impact excitation of the 2s"2S#->#2p"2P transition in C"3"+ were measured from 7.35 eV to 8.45 eV using the merged electron-ion-beams energy-loss technique. The results settle the discrepancy between two previous experiments using the crossed-beams fluorescence method, being in very good agreement with the older results [P. O. Taylor, D. Gregory, G. H. Dunn, R. A. Phaneuf, and D. H. Crandall, Phys. Rev. Lett. 39, 1256 (1977)] but less so with the more recent ones [D. W. Savin, L. D. Gardner, D. B. Reisenfeld, A. R. Young, and J. L. Kohl, Phys. Rev. A 51, 2162 (1995)]. The present measurements are also in good agreement with unitarized Coulomb-Born and close-coupling calculations. copyright 1998 The American Physical Society.

13

Absolute, cascade-free cross sections for the "2S#->#"2P transition in Zn"+ using electron-energy-loss and merged-beams methods  

International Nuclear Information System (INIS)

Absolute, cascade-free excitation cross sections in an ion have been measured for the resonance "2S#->#"2P transition in Zn"+ using electron-energy-loss and merged electron-ion beams methods. Measurements were carried out at electron energies of below threshold to 6 times threshold. Comparisons are made with 2-, 5-, and 15-state close-coupling and distorted-wave theories. There is good agreement between experiment and the 15-state close-coupling cross sections over the energy range of the calculations.

14

Absolute electron scattering cross sections for the "2S#->#"2P transition in Zn"+ using energy-loss and merged-beams methods  

International Nuclear Information System (INIS)

Using the electron energy-loss method in a merged electron-ion beams geometry absolute, cascade-free excitation cross sections have been measured for the resonance "2S#->#"2P transition in Zn"+. Measurements were carried out at electron energies of below threshold (threshold at 6.011 eV) to 40 eV. Results are in very good agreement with close-coupling calculations and, away from threshold, lie below absolute line-emission cross sections which include effects of cascade into the "2P state from higher levels.

1991-02-20

15

Merged-beams energy-loss technique for electron-ion excitation: Absolute total cross sections for O"5"+(2s#->#2p)  

International Nuclear Information System (INIS)

A merged-beams electron-energy-loss technique is described, by which absolute cross sections can be measured for near-threshold electron-impact excitation of multipy charged ions. Results are reported here for absolute total electron-impact excitation cross sections for the O"5"+(2s#->#2p) transition from below threshold to 1.6 eV above threshold. The experimental data are in good agremeent with a seven-state close-coupling calculation throughout the energy range of the experiment. Results agree with calculations showing that more than 90% of the electrons causing excitation are ejected in the backward direction in the center-of-mass frame. This backscattering is shown in both quantum-mechanical and semiclassical calculations. Evidence is observed for high-lying metastable autoionizing states with a lifetime of approximately 0.9 #mu#s which are made to ionize by electron impact.

16

Ab initio relativistic many-body calculation of hyperfine splitting of ^{113}Cd^+  

CERN Document Server

This work presents accurate ab initio determination of the hyperfine splitting for the ground state and few low-lying excited states of 113Cd+; important candidates for the frequency standard in the microwave region, using coupled-cluster theory (CC) in the relativistic framework. The calculated hyperfine splitting are well in agreement with recent experimental results. We have also carried out the lifetimes of the 5p2P1=2 and 5p2P3=2 states, which are in well agreement with recent experimental result (Moehring et al., PRA 73 023413, 2006). The roles of different electron correlation effects in the determination of these quantities are discussed and their contributions are presented in the CC terms.

2007-01-01

17

RESULTS FROM THE YOHKOH SATELLITE  

KoreaScience (Korea)

Full Text Available

1996-12-01

18

Non-equilibrium reaction mechanism in alpha-particle induced excitation function for sup 209 Bi up to 60 MeV  

Energy Technology Data Exchange (ETDEWEB)

Excitation functions ({alpha},3n) and ({alpha},4n) for {sup 209}Bi have been measured up to 60 MeV {alpha}-particle energy. The excitation functions are measured at 15{alpha}-particle energies by a stack foil technique in two steps. Excitation functions for the above two reactions have been reported for the first time in the energy range from 40 to 60 MeV. The measured experimental values are compared with the geometry-dependent hybrid (GDH) model in which the emission of particles prior to the equilibrium decay is taken into account whenever the interaction of projectile with the target nucleus is considered. It is found that the compound nucleus decay mechanism alone is unable to explain the experimental trend of our data. The initial exciton number 4 with different configurations has been tested and it is concluded that the configuration (2n + 2p + 0h) gives the best fit to the ...

1990-01-01

19

Non-equilibrium reaction mechanism in alpha-particle induced excitation function for "2"0"9Bi up to 60 MeV  

International Nuclear Information System (INIS)

Excitation functions (#alpha#,3n) and (#alpha#,4n) for "2"0"9Bi have been measured up to 60 MeV #alpha#-particle energy. The excitation functions are measured at 15#alpha#-particle energies by a stack foil technique in two steps. Excitation functions for the above two reactions have been reported for the first time in the energy range from 40 to 60 MeV. The measured experimental values are compared with the geometry-dependent hybrid (GDH) model in which the emission of particles prior to the equilibrium decay is taken into account whenever the interaction of projectile with the target nucleus is considered. It is found that the compound nucleus decay mechanism alone is unable to explain the experimental trend of our data. The initial exciton number 4 with different configurations has been tested and it is concluded that the configuration (2n + 2p + 0h) gives the best fit to the ...

20

Excitation cross sections for the ns "2S#->#np "2P resonance transitions in Mg"+ (n=3) and Zn"+ (n=4) using electron-energy-loss and merged-beams methods  

International Nuclear Information System (INIS)

Electron-excitation cross sections are reported for the 3s "2S#->#3p "2P(h,k) resonance transition in Mg"+ at energies from threshold (4.43 eV) to approximately 9 times threshold (40.0 eV). The electron-energy-loss merged-beams technique used in these measurements is described in detail. In addition, the method of separating contributions of the elastically scattered (Coulomb) and the inelastically scattered electrons in the present Mg"+ case and previously reported Zn"+ results [Phys. Rev. Lett. 67, 30 (1991)] is described. Comparisons in the experimental energy range are made for Mg"+ with the two five-state close-coupling theoretical calculations carried out herein, and with other published close-coupling, distorted-wave, and semiempirical calculations. The present Mg"+ cross sections and Zn"+ cross sections from earlier measurements are tabulated.

21

Electron-impact excitation of multiply-charged ions using energy loss in merged beams: e+Si"3"+(3s"2S_1_/_2)#->#e+Si"3"+(3p"2P_1_/_2_,_3_/_2)  

International Nuclear Information System (INIS)

For the first time absolute total cross sections for electron-impact excitation of a multiply-charged ion have been measured using an electron-energy-loss technique. Measurements were made near threshold for the process e + Si"3"+(3s"2S_1_/_2) #-># e+Si"3"+(3p"2P_1_/_2_,_3_/_2)-8.88 eV. The 10"-"1"5 cm"2 measured cross section agrees with results of 7-state close coupling calculations to better than the #+-#20% (90% CL) total uncertainty of the measurements. Convoluting the theoretical curve with a Gaussian energy distribution indicates an energy width of 0.15 < or approx. #DELTA#E < or approx. 0.20 eV. (orig.).

22

Resonant neutralization of He ions into excited states at Cu(110) and Ni(110) surfaces  

Energy Technology Data Exchange (ETDEWEB)

He ions incident at grazing angles on Cu(110) and Ni(110) surfaces are neutralised into triplet and singlet states, of which the 3p, 3d and 4d upper states are accessible to optical spectroscopy. In the energy range from 500 eV to 15 keV no significant energy dependence of the relative intensities of singlet and triplet lines was observed for scattering on Cu(110). The intensities from Ni(110) are higher and the singlet to triplet intensity ratio of the 3d to 2p transition is about 6% smaller than that from Cu(110). The results can be explained well by assuming resonant charge capture into excited He and intermediate formation of negative He/sup -/ states.

1984-03-01

23

Resonant neutralization of He ions into excited states at Cu(110) and Ni(110) surfaces  

International Nuclear Information System (INIS)

He ions incident at grazing angles on Cu(110) and Ni(110) surfaces are neutralised into triplet and singlet states, of which the 3p, 3d and 4d upper states are accessible to optical spectroscopy. In the energy range from 500 eV to 15 keV no significant energy dependence of the relative intensities of singlet and triplet lines was observed for scattering on Cu(110). The intensities from Ni(110) are higher and the singlet to triplet intensity ratio of the 3d to 2p transition is about 6% smaller than that from Cu(110). The results can be explained well by assuming resonant charge capture into excited He and intermediate formation of negative He"- states. (orig.).

1983-07-01

24

Electron-impact excitation of Si"3"+(3s#->#3p) using a merged-beam electron-energy-loss technique  

International Nuclear Information System (INIS)

For the first time, absolute cross sections for electron-impact excitation of a multiply charged ion have been measured using an electron-energy-loss technique. Cross sections for e+Si"3"+(3s "2S_1_/_2)#->#e+Si"3"+(3p "2P_1_/_2_,_3_/_2)-8.88 eV have been measured with an accuracy of #+-#20% (at 90% confidence level) over a narrow energy range (#+-#0.6 eV) about the threshold energy with an energy resolution of 0.2 eV. Results are in good agreement with close-coupling calculations.

25

Neutron-hole strengths and core coupling in /sup 87/Sr via the /sup 88/Sr("3He,#alpha#)/sup 87/Sr reaction  

International Nuclear Information System (INIS)

Neutron-hole states in /sup 87/Sr were studied by means of the /sup 88/Sr("3He,#alpha#)/sup 87/Sr reaction at 36 MeV. Angular distribution measurements were carried out from 3"0 to 41"0 (lab) and analyzed with the zero-range distorted-wave Born approximation method. Spectroscopic factors have been determined for about 50 discrete levels in /sup 87/Sr located below 6 MeV excitation energy and for the three lowest isobaric analog states 2p(3/2, 1f(5/2, and 2p(1/2 observed around 11 MeV. Many l = 1 and l = 3 discrete levels are observed in the 3--6 MeV excitation energy range. In addition, a large part of the 1f-2p strength is found to lie in the higher-lying continuum up to 13 MeV (about 10% and 40% for the l = 1 and 3 contributions, respectively). The distribution of the 1f-2p ...

26

Observation of high-lying weak autoionizing resonances of Ne, and Mg atoms by charge-separated photoion-yield method  

Energy Technology Data Exchange (ETDEWEB)

Doubly-excited 2s{sup -1}2p{sup -1}3pnp autoionizing resonance series of Ne atom as well as autoionizing resonances in the 2s region of Na and Mg atoms have been studied with monochromatized synchrotron radiation. Use of charge-separated photoion-yield method allowed us to detect these weak resonances in a clarified way in the yield curves of doubly-charged ions. The observed resonance states have been interpreted with the help of MCDF calculations, and the decay processes of these resonance states are discussed briefly.

2007-03-01

27

Observation of a surface peak in low energy implant depth profiles in silicon  

Energy Technology Data Exchange (ETDEWEB)

In situ Auger sputter depth profiles of saturation implants of 3 keV N/sub 2//sup +/ in silicon at room temperature exhibit a sharp peak in the nitrogen concentration in the outermost layers, followed by a monotonic decrease. No broad plateau was observed. The energy of the Auger line corresponding to the Si(2p) core electron excitation, monitored throughout the profiling, exhibits a chemical shift of up to 7 eV at the surface peak concentration. Inert gas ion post-bombardment of unsaturated implants significantly modifies the profile, and supports the suggestion that the surface peak arises through radiation enhanced diffusion of implanted atoms.

1984-03-01

28

Solar Radiation Pressure Binning for the Geosynchronous Orbit  

Science.gov (United States)

Orbital maintenance parameters for individual satellites or groups of satellites have traditionally

2011-01-01

29

Electron momentum spectroscopy of H_2 and D_2: Ionization to ground and excited final states  

International Nuclear Information System (INIS)

The symmetric noncoplanar (e,2e) cross sections (momentum profiles) of H_2 and D_2 for the transitions to the 2p#sigma#_u and 2s#sigma#_g excited ion states have been measured, relative to the ground-state ion transition, using a high-sensitivity multichannel momentum-dispersive electron momentum spectrometer (EMS) at an impact energy of 1200 eV. Newly calculated plane-wave impulse approximation (PWIA) cross sections, based on a full-configuration-interaction H_2 wave function, are compared to the experimental results. These calculations are in better agreement with the experimental results for the transition to the 2s#sigma#_g ion state than the earlier theoretical work of Liu and Smith, Jr. [Phys. Rev. A 31, 3003 (1985)] which has been found to be in error. Nevertheless, significant discrepancies between the relative experimental and theoretical cross sections are observed for the transitions to ...

30

Combining Satellite and in Situ Data with Models to Support Climate Data Records in Ocean Biology  

Science.gov (United States)

The satellite ocean color data record spans multiple decades and, like most long-term satellite

2011-01-01

31

Transformational Satellite (TSAT) Communications Systems. ...  

Science.gov (United States)

... The seven existing space/airborne programs are the Defense Satellite Com- munications System (DSCS), Milstar, communications re- lay ...

2007-07-01

32

SPACE FLIGHT 1999 - NASA  

Science.gov (United States)

Mission losses were incurred by an early warning satellite and a Milstar-2 communications satellite when their launch vehicles malfunctioned, the first, ...

33

A Secure and Efficient Communications Architecture for ...  

Science.gov (United States)

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

2008-06-19

34

Cu adatom interactions with single- and polycrystalline Bi_2Ca/sub 1+//sub x/Sr/sub 2-//sub x/Cu_2O/sub 8+//sub y/ and YBa_2Cu_3O/sub 7-//sub x/  

International Nuclear Information System (INIS)

The electronic structure and surface interactions vapor-deposited Cu on single-crystal and polycrystalline Bi_2Ca/sub 1+//sub x//sub Sr>2-//sub x//sub Cu>2/O/sub 8+//sub y/ were studied using x-ray photoelectron spectroscopy. The results are compared to the Cu/YBa_2Cu_3O/sub 7-//sub x/ interface. Changes in the Cu 2p satellite emission indicate that the Cu adatoms do not disrupt Bi_2Ca/sub 1+//sub x/Sr/sub 2-//sub x/Cu_2O/sub 8+//sub y/ as extensively as YBa_2Cu_3O/sub 7-//sub x/. However, deposition of Cu induces changes in the Bi environment in the superconductor, and surface segregation of Bi metal was observed at high coverages. Core-level attenuation results suggests minimal outdiffusion of oxygen, in contrast with what is observed for Cu/YBa_2Cu_3O/sub 7-//sub x/.

5545-01-01

35

Measurement and analysis of alpha particle induced reactions on praseodymium  

International Nuclear Information System (INIS)

Excitation functions (EFs) for the reaction "1"4"1Pr(#alpha#, n)"1"4"4Pm and "1"4"1Pr(#alpha#, 2n)"1"4"3Pm have been measured using "1"4"1Pr as a target up to 50 MeV #alpha#-particle energy. Stacked foil activation technique and #gamma#-ray spectroscopy using 100 cm"3 Ge (Li) detector, has been used. Excitation functions are also calculated theoretically using Blann's geometry dependent hybrid (GDH) model code ALICE-91, with and without inclusion of pre-equilibrium particle emission. It has been observed that high-energy tails of the EFs are dominated by pre-equilibrium reaction mechanism. With the accepted set of input parameter, initial exciton number n_0=4 (2p + 2n + 0h), a good qualitative agreement is found. However, quantitative agreement for this magic nucleus"1"4"1Pr is also good when theoretical calculations are normalized by a multiple factor of 0.5. (author)

2005-04-01

36

Muscle satellite cell proliferation and association: new insights from myofiber time-lapse imaging  

UK PubMed Central (United Kingdom)

BackgroundAs the resident stem cells of skeletal muscle, satellite cells are activated by extracellular cues associated with local damage. Once activated, satellite cells will re-enter...Full Text Available

37

METEOROLOGICAL SATELLITES - NASA's History Office  

Science.gov (United States)

Study of cloud pictures taken from rockets, such as figure 1, indicates that it is .... One might visualize a "Satellite Weather Data Center" where incoming data would ... about 300 miles; satellite packaging, containing the sensors, storage, power, ...

38

VIBRATION ISOLATION OF SATELLITE TAPE RECORDERS  

Science.gov (United States)

A standardized method of shock and vibration isolation for satellite tape recorders has been developed. Using readily avail- able components, the isolators ...

39

United States Space Activities - NASA  

Science.gov (United States)

Mission losses were incurred by an early warning satellite and a Milstar-2 communications satellite when their launch vehicles malfunctioned, the first, ...

40

The NASA Ames Small Satellite Program - Goddard Engineering ...  

Science.gov (United States)

He commanded the 50th Space Wing, which is responsible for 60 satellites. ... to produce space systems and launchers capable of tailored military effects on ...

41

The Current Status of Russian/CIS Communication Satellites  

Science.gov (United States)

... 4302, and to the Office of Management and Budget, Paper-work ... link coverage areas, so it is possible to receive your own ... mestic Ku-band satellite. ...

1994-09-01

42

Satellite Calibration Data. Annual Data Report - 1977  

Science.gov (United States)

... in Taylor and Williamson.* Most satellite sensors cannot be ... The coordinates of the rocket Ii ... I - Incoming Global Radiant Flux between 0.285 and ...

1979-08-01

43

SPACEWARN Bulletin 579 - the NSSDC! - NASA  

Science.gov (United States)

Mar 5, 2003 ... The 4545 kg, 5 kW satellite belongs to the fleet of Milstar 2 satellites ... Being the fifth in the Milstar 2 series, it also carries the ...

44

NASA Satellite Measures Deforestation : Image of the Day  

Science.gov (United States)

Sep 14, 2005 ... For decades, the Brazilian government has been basing estimates of Amazon deforestation on high-resolution Landsat satellite data. Having ...

45

Environmental Impact Analysis Process. Final Environmental ...  

Science.gov (United States)

... Abstract : The United States Air Force (USAF) currently operates the Milstar satellite system to provide Military Satellite Communication Systems ...

2001-02-15

46

Contamination Effects of Satellite Material Outgassing ...  

Science.gov (United States)

... A detailed analysis of QCM errors is ... Surface Effects of Satellite Outgassing Products." AIAA Journal ... 9. Rauschenbach, H. S. Solar Cell Array Design ...

1990-12-01

47

A Notional Battlespace for Simulating and Testing Dynamic ...  

Science.gov (United States)

... 23 Milstar 25 A Notional Battlespace For Dynamic Wireless Network Simulation/Testing ... Figure 16: GPS Satellite 23 Figure 17: Milstar Satellite 25 ...

2006-06-01

48

Extended observation and analysis of the first overtone spectrum of solid parahydrogen  

Energy Technology Data Exchange (ETDEWEB)

The first overtone spectrum of solid parahydrogen with various low ortho impurity levels has been studied in detail using a White-type external multireflection system. For the Q{sub 2{l_arrow}0}(0) transition the authors have observed the fully resolved threefold splitting due to the crystal field effect. Furthermore, the authors have obtained a rich satellite spectrum associated with the transitions Q{sub 2{l_arrow}0}(0) and Q{sub 2{l_arrow}0}(1) at different ortho-H{sub 2} contents revealing information about the ortho-H{sub 2} pair interaction in the second vibrationally excited state of the hydrogen molecule. A preliminary analysis and assignment of these satellite transitions will be presented. Another point of study was the spectral region around 8300 cm{sup -1}, where the double transitions of the type Q{sub 1{l_arrow}0}(n) + Q{sub 1{l_arrow}0}(n{prime}) (n, n{prime} = 0,1) are located. The most remarkable features ...

1996-12-31

49

Ultraviolet upconversion luminescence enhancement in Yb3+/Er3+-codoped Y2O3 nanocrystals induced by tridoping with Li+ ions  

International Nuclear Information System (INIS)

Ultraviolet (UV) upconversion (UC) luminescence in Yb3+/Er3+-codoped yttrium oxide (Y2O3) nanocrystals can be enhanced by orders of magnitude via tridoping further with Li+ ions under diode laser excitation of 970 nm. Sensitized three-photon UC radiations at 390 and 409 nm, corresponding to the 4G11/2?4I15/2 and 4H9/2?4I15/2 of Er3+ ions, respectively, present an enhancement time of about 33 times, which is larger than the 24 times enhancement for the UC green radiation. The UV UC radiation at 320 nm that corresponds to the 2P3/2?4I15/2 of Er3+ ions has also been greatly enhanced. Theoretical calculations interpret that all the observed enhancement times of UV UC radiations arise from the prolonged lifetimes of their intermediate states.

2009-03-01

50

Excitonic transitions in InGaP/InAlGaP strained quantum wells  

International Nuclear Information System (INIS)

Excitonic transitions in metalorganic vapor phase epitaxially grown In_xGa_1_-_xP/In_0_._4_8(Al_0_._7Ga_0_._3)_0_._5_2P strained single quantum-well structures are characterized using low-temperature photoluminescence and photoluminescence excitation (PLE) spectroscopies. The structures consist of several uncoupled quantum wells with thicknesses between 1.2 and 11.3 nm, and compositions x of 0.48 (nominally lattice matched) and 0.56 (#approx#0.6% biaxial compressive strain). The photoluminescence spectra exhibit intense peaks over the wavelength range 550--650 nm, with linewidths between 7 and 23 meV depending on the well thickness. The PLE spectra reveal strong heavy-hole and light-hole transitions, as well as higher-order (n=2) transitions in the thicker wells. The heavy-hole/light-hole splitting shows little dependence on well thickness in the strained structures, indicating a relatively large conduction band offset of ...

51

Testing of solar cells for communication satellites  

International Nuclear Information System (INIS)

... cadmium sulfides communications electrons performance testing physical

56

Small-satellite technology and applications III  

Energy Technology Data Exchange (ETDEWEB)

This third conference on small-satellite applications has combined a number of significant and timely presentations on the status, in the US and on the international front, of this emerging industry. Presentations by all of the major Department of Defense activities in this field, including an overview of the ARPA CAMEO multispectral remote sensing satellite program, space activities at the Air Force Phillips Laboratory, and a space systems capabilities overview of the Naval Research Laboratory, are complemented by presentations from several international activities on their accomplishments and progress in the development of remote sensing satellite programs. For example: Spar Aerospace of Canada presented an overview of the progress they have made in establishing a space program through the use of small satellites, and the University of Surrey and Spar Aerospace provided an overview of the application ...

1993-01-01

57

Conference excitement recalled by "CERN courier" report  

CERN Multimedia

Conference excitement recalled by "CERN courier" report

1962-01-01

58

Hydrogen production for better nuclear utilization  

International Nuclear Information System (INIS)

... no. 2) p. 27-28. economics hydrogen power reactors nonmetals (ELEMENTS

1972-08-22

59

Constituents isolated of Maytenus truncata Reiss leaves  

International Nuclear Information System (INIS)

Portuguese 2006 [2 p.] Brazil Salazar, Gloria Del Carmen Melendez .

2006-05-19

60

Automatic Extraction of Open Space Area from High Resolution Urban Satellite Imagery  

CERN Document Server

In the 21st century, Aerial and satellite images are information rich. They are also complex to analyze. For GIS systems, many features require fast and reliable extraction of open space area from high resolution satellite imagery. In this paper we will study efficient and reliable automatic extraction algorithm to find out the open space area from the high resolution urban satellite imagery. This automatic extraction algorithm uses some filters and segmentations and grouping is applying on satellite images. And the result images may use to calculate the total available open space area and the built up area. It may also use to compare the difference between present and past open space area using historical urban satellite images of that same projection

2011-01-01

61

Satellite power systems (SPS) concept definition study (exhibit d). Volume 4: operations analyses. Final report  

Energy Technology Data Exchange (ETDEWEB)

Using a coplanar, end-mounted antenna as a baseline, various configuration trades were performed to select a preferred solid state concept. The increase in efficiency that could be realized by use of multi bandgap solar cells, either with klystron or solid state antenna was evaluated. Satellite configurations were developed to exploit the sandwich antenna concept wherein solar cells are located on one side of the antenna panel and solid state dc/RF converters on the other side. These concepts entailed various primary and secondary reflector arrangements for directing solar energy to the solar cell side of the antenna with higher concentration ratios than used on the coplanar configurations. Operations analysis included development of a satellite construction scenario, a concept for the SCB, a top-level satellite construction operation, construction operation, construction timelines and crew sizes, mass flows to orbit, and a ...

1981-03-01

62

Medical image transmission via communication satellite. Evaluation of bone scintigraphy  

International Nuclear Information System (INIS)

As compared with terrestrial circuits, the communication satellite possesses superior characteristics such as wide area coverage, broadcasting, high capacity, and robustness to disasters. Utilizing the narrow band channel (64 kbps) of the geostationary satellite JCSAT 1 located at the altitude of 36,000 km above the equator, the authors investigated satellite-relayed medical imagings by video signals, with bone scintigraphy as a model. Each bone scintigraphy was taken by a handy-video camera, digitalized and transmitted from faculty of technology located at 25 kilometers apart from our department. Clear bone scintigraphy was obtained via satellite, as seen on the view box. Eight nuclear physicians evaluated 20 cases of bone scintigraphy. ROC (Receiver Operating Characteristic) analysis was performed between the scintigraphies on view box and via satellite by the rating method. The ...

63

Comparison of the UHF Follow-on and MILSTAR Satellite Communication Systems.  

Science.gov (United States)

The author compares the UHF Follow-on and MILSTAR satellite communication systems. The comparison uses an analytical hierarchy process. Although the two systems have been tasked with different missions, a comparison of cost, capability, and orbit is condu...

1991-01-01

64

Can satellites deliver substructures and black holes to inner halo by dynamical friction?  

CERN Document Server

Dynamical friction, or the rate for a satellite to decay its orbit in a host galaxy halo, is often severely overestimated when applying the ChandraSekhar's formula without correcting for the tidal loss of the satellite and the adiabactic growth of the host galaxy potential over the Hubble time. As a satellite decays to the inner and denser region of the host galaxy, the high ambient density boosts the exchange of energy and angular momentum between the satellite and the host, but on the other hand shrinks the Roche lobe of the satellite by tides. Eventually the processes of orbital decay and tidal stripping hang up altogether once the satellite is light enough. These competing processes can be modeled analytically for a satellite if we parametrize the massloss history by an empirical formula. We also take into account the adiabatic ...

2003-01-01

65

Superconducting Switchable Circulator  

Science.gov (United States)

... as time delay shifters for large-area phased arrays in military (MILSTAR) as well as commercial (Sky phone and other satellite communication) systems, ...

66

Satellite imagery as verification tool for safeguards  

International Nuclear Information System (INIS)

... Formosat (Taiwan, China) 2m WorldView-1 (US) 0.5m The SIAU is using

2009-02-03

67

Milstar Quicklook  

Science.gov (United States)

Milstar picture Milstar is a series of advanced US military communications satellites designed to provide global jam-resistant communications for military users. ...

68

Mike Dickerson - NASA Quest  

Science.gov (United States)

Before working at JPL he was the Chief Engineer for the Milstar Satellite Avionics and several Military space programs. His technical background is in ...

69

Forging Space Warriors  

Science.gov (United States)

... These three roles are critical to de- fending the Nation through the control Milstar satellite on Titan IV at Cape Canaveral. ...

2011-05-15

70

Florida State University - Explores! World Headquarters  

Science.gov (United States)

EXPLORES! (EXPloring and Learning the Operations and Resources of Environmental Satellites!) is an educational outreach program developed at Florida State University with the intention of introducing weather satellite receiving technology into the primary and secondary school classrooms. The website furnishes real time high resolution imagery and tropical updates. Visitors can find historical accounts of the civilian weather satellites launched by the United States. Educators can discover kindergarten through twelfth grade resources and curriculum. Users can learn how to become a part of the WXSAT-L community email list where weather satellite professionals, amateurs, and hobbyists converse about scientific, tracking, launching, and operations information.

71

Downlink Acquisition and Tracking Procedures for the ...  

Science.gov (United States)

... terminal capable of operating from 75 to 2,400 bps with low inclination, geosynchronous FLTSAT EHF package and Milstar satellites. ...

1993-09-14

72

Carbon Fiber Reinforced Glass Matrix Composites for Satellite ...  

Science.gov (United States)

... The ultimate compressive strength (UCS) for the HMU/BSG composite is essentially equivalent to the tensile strength exhibited by this system. ...

1992-06-01

73

Heterodifunctional ligands derived from monooxidized Bis(phosphino)amines. Synthesis and transition metal (Molybdenum(0), Tungsten(0), Rhodium(I), Palladium(II), and Platinum(II)) complexes of (Diphenylphosphino)(diphenylphosphinothioyl)- and (Diphenylphosphino) (diphenylphosphinoselenoyl)phenylamine, Ph[sub 2]PN(Ph)P(E)PH[sub 2] (E = S, Se). Crystal and molecular structure of the Pt(II) Complex [Cl[sub 2]P[ovr tPPh[sub 2]N(Ph)P(S)]Ph[sub 2  

Energy Technology Data Exchange (ETDEWEB)

Bis(diphenylphosphino)phenylamine can be selectivity oxidized by S or Se in toluene or hexane solvents to the monooxidized thioyl or selenoyl products Ph[sub 2]PN(PH)PPh[sub 2]=E, (E = S, Se). These compounds act as bidentate chelate ligands toward metal complexes forming (CO)[sub 4]M(LL) (M = Mo, W), CO(Cl)Rh(LL), and Cl[sub 2]M(LL), (M = Pt, Pd) where (LL) is the thioyl or selenoyl derivative of the aminobis(phosphine). IR and NMR data are given for all complexes. The carbonyl infrared stretching frequencies show that the chelates form with the phosphine cis to any CO which is present. The [sup 31]P NMR of all complexes of two doublets except for the Rh complexes wherein the Rh spin also couples to phosphorous to produce two doublets of doublets. The [sup 2]J[sub PP] values range from 56 to 112 Hz. [sup 1]J[sub PSe] coupling provide valuable assistance for the assignment of the phosphorus resonances which range widely from 55 to 126 ppm for P[sup III] and from 60 to 80 ppm for the ...

1993-12-08

75

Two- and three-phonon states in "8"8Sr  

International Nuclear Information System (INIS)

... de-excitation excited states gamma radiation inelastic scattering mev range

77

Theoretical determination of 1H e 13C shielding constants of thymol  

International Nuclear Information System (INIS)

Portuguese 2004 2 p. Brazil Resende, Jarbas Magalhaes Vieira, Gessy

2004-07-27

78

SiAlON polytypoids in polymer-filler derived ceramics  

International Nuclear Information System (INIS)

English 2006 2 p. Brazil Rocha, RM Centro Tecnico Aeroespacial, Sao

80

Dayside auroral activity and magnetospheric boundary layer phenomena  

Energy Technology Data Exchange (ETDEWEB)

Selected case studies of auroral structure/activity observed at different local times on the dayside are presented and discussed in the context of electrodynamic coupling between the different magnetospheric boundary regions and the ionosphere. The first case addresses the question of the auroral signatures of the two boundary regions referred to as cusp and cleft/LLBL. Combined ground-based and satellite data reveal the different latitudinal zones of auroral forms/particle precipitation/field-aligned current and the relationship with the respective magnetospheric plasma populations, i.e. CPS, BPS, LLBL, and the plasma mantle. Midday auroral breakup events and the related ionospheric ion drift and magnetic observations show many of the features that have been predicted to be ionospheric signatures of flux transfer events. An alternative explanation that has been proposed by others, i.e. ionospheric effect of magnetopause perturbations excited ...

1990-07-01

81

Satellite remote sensing of Spratly Islands using SAR  

British Library Electronic Table of Contents (United Kingdom)

Spratly Islands, located in the southern part of the South China Sea (SCS), consist of more than 100 small islands, coral reefs and banks. Remote sensing is the only way to obtain a synoptic view of all of the islands in such a large area. It has been demonstrated that satellite synthetic aperture radar (SAR) imagery is a very powerful tool for monitoring meso-scale and small-scale ocean processes in a large area. In this study, satellite SAR images were used to study the ocean environment in the area of Spratly Islands. The aim was to understand the capability of satellite remote sensing to monitor ocean processes and provide information for future field studies. Two sets of high-resolution European Remote Sensing satellite (ERS)-2 SAR images over the entire Spratly Islands area were coll...

2008-01-01

82

Numerical modeling of a Global Navigation Satellite System in a general relativistic framework  

CERN Document Server

In this article we model a Global Navigation Satellite System (GNSS) in a Schwarzschild space-time, as a first approximation of the relativistic geometry around the Earth. The closed time-like and scattering light-like geodesics are obtained analytically, describing respectively trajectories of satellites and electromagnetic signals. We implement an algorithm to calculate Schwarzschild coordinates of a GNSS user who receives proper times sent by four satellites, knowing their orbital parameters; the inverse procedure is implemented to check for consistency. The constellation of satellites therefore realizes a geocentric inertial reference system with no \\emph{a priori} realization of a terrestrial reference frame. We show that the calculation is very fast and could be implemented in a real GNSS, as an alternative to usual post-Newtonian corrections. Effects of non-gravitational perturbations on ...

2010-01-01

83

Magnetic moment of the three-quasiparticle state in "1"7"7Ta  

International Nuclear Information System (INIS)

An experimental investigation was made of the #gamma#-transitions feeding or de-exciting the 1355 keV isomeric state in "1"7"7Ta. The E2/M1 mixing ratios for the 311 keV interband transition from the isomer and for the 271 keV and the 295 keV intraband transitions within the rotational band on the isomer were determined to be delta = 0.29sup(+0.11)sub(-0.06), 0.25sup(+0.05)sub(-0.03) and 0.30sup(+0.06)sub(-0.08), respectively, employing combined measurements of the linear polarization and angular distribution of the #gamma#-ray with the aid of conversion electron measurements. Spin and parity assignments of the isomer were confirmed to be 21/2"-. The half-life of the isomer was remeasured to be Tsub(1/2) = 5.0 +- 0.2 #mu#s and the magnetic moment was found to be #mu# = 0.080 +- 0.014 #mu#sub(N). The gsub(K) and gsub(R) factors for the band on the isomer were deduced separately to be gsub(K=21/2"-) = 0.062sup(+0.011)sub(-0.008) and gsub(R) = ...

84

Crystal and electronic structures, luminescence properties of Eu2+-doped Si6-zAlzOzN8-z and MySi6-zAlz-yOz+yN8-z-y (M=2Li, Mg, Ca, Sr, Ba)  

International Nuclear Information System (INIS)

The crystal structure, electronic structure, and photoluminescence properties of EuxSi6-zAlz-xOz+xN8-z-x (x=0-0.1, 0xMySi6-zAlz-x-yOz+x+yN8-z-x-y (M=2Li, Mg, Ca, Sr, Ba) have been studied. Single-phase EuxSi6-zAlz-xOz+xN8-z-x can be obtained in very narrow ranges of x?0.06 (z=0.15) and z2+ ions can be incorporated into nitrogen-rich Si6-zAlzOzN8-z. The Eu2+ ion is found to occupy the 2b site in a hexagonal unit cell (P63/m) and directly connected by six adjacent nitrogen/oxygen atoms ranging 2.4850-2.5089 A. The calculated host band gaps by the relativistic DV-X? method are about 5.55 and 5.45 eV (without Eu2+ 4f5d levels) for x=0 and 0.013 in EuxSi6-zAlz-xOz+xN8-z-x (z=0.15), in which the top of the 5d orbitals overlap with the Si-3s3p and N-2p orbitals within the bottom of the conduction band of the host. EuxSi6-zAlz-xOz+xN8-z-x shows a strong green emission with a broad Eu2+ band centered at about 530 nm under UV to near-UV ...

2008-12-01

85

Recent Korean R&D in Satellite Communications  

Science.gov (United States)

The R&D in satellite communications in Korea has been driven mainly by KCC (Korea Communications Commission) but in a small scale compared to Korea space development program organized by MEST (Ministry of Education, Science and Technology). Public and civilian satcom sector R&D has been led mainly by ETRI with small/medium companies contrary to rare investment in private sector while military sector R&D has been orchestrated by ADD with defense industry. By the COMS (Communication, Ocean and Meteorological Satellite) experimental Ka-band payload, Korea pursues a space qualification of own technology for national infrastructure evolution as well as industrialization of space R&D results. Once COMS launched and space qualified in 2009, subsequent application experiments and new technology R&D like UHDTV will entail service and industry promotion. The payload technology is expected for the next Korean commercial ...

2009-01-01

86

European Space Agency announces contest to "Name the Cluster Quartet"  

Science.gov (United States)

1. Contest rules The European Space Agency (ESA) is launching a public competition to find the most suitable names for its four Cluster II space weather satellites. The quartet, which are currently known as flight models 5, 6, 7 and 8, are scheduled for launch from Baikonur Space Centre in Kazakhstan in June and July 2000. Professor Roger Bonnet, ESA Director of Science Programme, announced the competition for the first time to the European Delegations on the occasion of the Science Programme Committee (SPC) meeting held in Paris on 21-22 February 2000. The competition is open to people of all the ESA member states (*). Each entry should include a set of FOUR names (places, people, or things from history, mythology, or fiction, but NOT living persons). Contestants should also describe in a few sentences why their chosen names would be appropriate for the four Cluster II satellites. The winners will be those which are considered most suitable ...

2000-02-01

87

contents - NASA History Office  

Science.gov (United States)

David N. Spires and Rick W. Sturdevant, "From Advent to Milstar: The United States Air Force and the Challenges of Military Satellite Communications. Chapter 8 ...

88

Worldwide Report, Telecommunications Policy, Research and ...  

Science.gov (United States)

... 80 Briefs New Television Transmitter 81 Matadi Satellite Earth Station Inaugurated (Kinshasa AZAP, various dates) 82 Ramazani Marks Opening ...

1985-12-31

89

Workshop Agenda - Applied Science and Technology Project Office - NASA  

Science.gov (United States)

Purpose: Assess the feasibility of using NASA satellite data to monitor persistent saltwater intrusion in coastal marshes. End User: USGS National Wetlands ...

90

Visible Earth: Haitian Deforestation - Visible Earth - NASA  

Science.gov (United States)

Jun 8, 2006 ... It also reflects the large amount of deforestation that has occurred on the Haitian side of the border. One can easily see from satellite imagery ...

91

UARS Particle Environment Monitor (PEM) Level 3AT - Mirador - NASA  

Science.gov (United States)

May 11, 2011 ... The Particle Environment Monitor (PEM) on NASA's Upper Atmosphere Research Satellite (UARS) measures the type, amount, energy, and ...

92

UARS PEM Level 2 VMAG AC - Mirador - NASA  

Science.gov (United States)

May 11, 2011 ... The Particle Environment Monitor (PEM) on NASA's Upper Atmosphere Research Satellite (UARS) measures the type, amount, energy, and ...

93

Typhoon Aere : Image of the Day - NASA Earth Observatory  

Science.gov (United States)

Aug 25, 2004 ... The Tropical Rainfall Measuring Mission or TRMM satellite provided this image of Typhoon Aere over the western Philippine Sea as it was ...

94

The restructured Milstar program  

Science.gov (United States)

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

1992-03-01

95

The Limits of Spacepower  

Science.gov (United States)

... to light-light a laser or directed energy weapon would ... space-based components... .the most likely threats are direct ascent anti-satellite weapons; ...

2001-05-18

96

SPACEWARN Bulletin 682 - the NSSDC! - NASA  

Science.gov (United States)

Oct 1, 2010 ... AEHF 1 is the first of four Advanced Extremely High Frequency (AEHF) satellites that will replace the earlier Milstar system. The AEHF ...

97

PolyRAD Space Radiation Shield for Commercial-Off-The  

Science.gov (United States)

Defense satellites, including the next generation GPS and MILSTAR, continue to require TID well above that of most COTS silicon. ...

98

Nor'easter Floods  

National Aeronautics and Space Administration (NASA)

This video of GOES satellite imagery was created from data compiled March 8 through 16, 2010. It shows flooding rains from a Nor'easter that soaked the U.S. Northeast.

2010-03-24

99

News - NASA Earth Observatory  

Science.gov (United States)

Satellite Observations of the Southeast Pacific Intertropical Convergence Zone During 1993-1998, Halpern, D.; Hung, C.-W., Journal of Geophysical Research ? ...

100

NTC Information  

Science.gov (United States)

602-906-5555 Important Links Electronic Reading Room HazMat Mgrs Tools Satellite Network Security Procedures Staff Directory Links - Partners Restricted access BLM NTC INTRANET...

2011-10-15

101

NEX - Analysis of ENSO Dynamics and ThermoDynamics in the ... - NASA  

Science.gov (United States)

Analysis of ENSO Dynamics and ThermoDynamics in the Western Pacific Warm Pool - An Application of Multi-Sensor Satellite Observations. ...

102

NASA - Pico-Satellite Solar Cell Experiment (PSSC)  

Science.gov (United States)

Jun 10, 2011 ... The PSSC is a picosatellite designed to test the space environment by providing a testbed to gather data on new solar cell technologies.

103

N95- 19645 - NASA Technical Report Server (NTRS)  

Science.gov (United States)

Milstar is a flexible, robust satellite communications ... of the Milstar system includes services capable of supporting status reporting, ...

104

Monte Carlo simulations of precise timekeeping in the Milstar communication satellite system  

Science.gov (United States)

The Milstar communications satellite system will provide secure antijam communication capabilities for DOD operations into the next century. In order to accomplish this task, the Milstar system will employ precise timekeeping on its satellites and at its ground control stations. The constellation will consist of four satellites in geosynchronous orbit, each carrying a set of four rubidium (Rb) atomic clocks. Several times a day, during normal operation, the Mission Control Element (MCE) will collect timing information from the constellation, and after several days use this information to update the time and frequency of the satellite clocks. The MCE will maintain precise time with a cesium (Cs) atomic clock, synchronized to UTC(USNO) via a GPS receiver. We have developed a Monte Carlo simulation of Milstar's space segment timekeeping. The simulation includes the effects of: uplink/downlink time transfer ...

1995-05-01

105

Modeling the AIM-9 Sidewinder Repair Line through Discrete ...  

Science.gov (United States)

... of electronic systems (satellite terminals, radio and ... helps organizations investigate the stochastic nature of ... cycle time, maximum queue lengths, and ...

2009-06-01

106

INTERPRETATION OF RADAR DATA FROM THE ICY GALILEAN SATELLITES AND ...  

Science.gov (United States)

(1989], however, we modeled the phase using a sum of simple power law terms. We. chose to do our work on Triton's atmosphere using the exponential functions ...

107

Human Interfaces for Robotic Satellite Servicing  

Science.gov (United States)

... of China Lake Naval Weapons Center, California. ... Figure 4: The Space-Based Laser cleaning ... of Aeronautics and Astronautics (AIAA) Space 2001 ...

2011-05-13

109

Exoplanet Community Report - Exoplanet Exploration Program - NASA  

Science.gov (United States)

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

110

EHF Satellite Communications-on-the-Move Blockage ...  

Science.gov (United States)

... Wheeled Vehicle) equipped with a MILSTAR terminal was driven ... textbooks including Ronald W. Wolff, Stochastic Modeling and The ... Queue Length ...

2004-11-02

111

Deformation and seismicity of Taiwan  

UK PubMed Central (United Kingdom)

14C-dated Holocene coastal uplift, conventional and satellite geodetic measurements, and coseismic and aseismic fault slip reveal the pattern of distributed deformation at Taiwan resulting...Full Text Available

2000-10-10

112

Deep Space Probe Science Experiment  

Science.gov (United States)

Briefly, 48 MOS microparticle sensors (essentially the same as those flown on .... at the Naval Research Lab to interpret the polarization of the incoming radio .... Adapter Satellite, to be published in Journal of Spacecraft and Rockets, 1994. ...

113

Cisco Presentation Guide - NASA  

Science.gov (United States)

MilStar,. Globalstar,. Others. DVB. Satellite. Internet. Home Agent. Foreign Agent. Foreign Agent . Reparenting the HA. Primary. Home Agent. Secondary ...

114

Benthic Habitat of Oahu Derived From IKONOS and Quick Bird Satellite Imagery, 2004-2006  

Science.gov (United States)

... Coastal Monitoring and Assessment, the University of Hawaii, BAE Systems Spectral Solutions and Analytical Laboratories of Hawaii, LLC. ... ...

115

Automated Pharmacy Patient Medication Profiling System  

UK PubMed Central (United Kingdom)

The Systems Development Group and the Pharmacy Service of the Washington D.C. VAMC are involved in automating the administrative and clinical data requirements of a satellite out-patient pharmacy....Full Text Available

1981-11-04

116

Adhoc Wireless Network Control: Energy Efficiency and ...  

Science.gov (United States)

... 3 Illustration of the hidden terminal problem in ... satellite downlink subject to stochastic power demands ... be immediately served, queueing effects are ...

2009-12-01

117

Intercombination transitions in beryllium-like and boron-like iron  

Energy Technology Data Exchange (ETDEWEB)

Beam-foil spectroscopy techniques have been used to study intercombination transitions in Be-like Fe{sup 22+} and B-like Fe{sup 21+}. The method of time delayed spectroscopy was used to identify the Be-like 2s{sup 2} {sup 1}S{sub 0}-2s2p {sup 3}P{sub 1} and B-like 2s{sup 2}2p {sup 2}P{sub 3/2}-2s2p{sup 2} {sup 4}P{sub 5/2} transitions. Intensity decay curves for these transitions were recorded and level lifetimes were obtained. The latter were found to be 17.5 {+-} 1.5 ns for the Be-like 2s2p {sup 3}P{sub 1} level and 14.8 {+-} 1.0 ns for the B-like 2s2p{sup 2} {sup 4}P{sub 5/2} level. (orig.).

1997-04-01

118

Inner-shell excitation of intrinsic luminescence and resonantly excited X-ray fluorescence at Be 1s edge in oriented BeO crystals  

International Nuclear Information System (INIS)

The results of studies of the time-resolved luminescence of self-trapped excitons (STE) with different multiplicity as well as the X-ray emission in oriented BeO crystals under excitation in the vicinity of the 1 s Be photoabsorption edge are presented. The branching of the electronic excitations relaxation depends strongly on the crystal orientation after the inner-shell excitation. The common features between the processes of the STE luminescence and resonantly excited X-ray fluorescence have been discussed.

2007-05-21

119

np-nh bands in the N=28 isotones  

CERN Document Server

The existence of n-particle n-hole deformed yrare bands in the N=28 isotones is explored using full pf-shell diagonalizations and the Lanczos Strength Function method. We find different 2p-2h and 4p-4h collective bands that, when allowed to mix, more often disappear. Only the 2p-2h yrare band in Cr-52 and the 4p-4h yrare band in Ni-56 survive, and only in this latter case, due to the reduced density of 2p-2h states, can the band be seen as a gamma-cascade.

2002-01-01

120

Three-particle and anomalous excited states of "1"0"1Tc nucleus  

International Nuclear Information System (INIS)

... energy levels excited states gamma spectra internal conversion li-drifted ge

1973-01-29

122

Radionuclide X-ray fluorescence analysis. 1: Excitation of X-ray fluorescense radiation by nuclear radiation  

Science.gov (United States)

The principles of radionuclide excitation of X-ray fluorescence radiation and its application in

1972-01-01

126

Fixation of CO_2 and export of photosynthate by the carpel in Pisum sativum  

International Nuclear Information System (INIS)

... School of Plant Biology. v. 23(2) p. 316-322. carbon dioxide absorption carbon

1970-01-01

129

Single-event burnout of power MOSFET devices for satellite application  

International Nuclear Information System (INIS)

Single-event burnout (SEB) sensitivity was tested for power MOSFET devices, JTMCS081 and JTMCS062, which were made in Institute of Microelectronics, Chinese Academy of Sciences, using californium-252 simulation source. SEB voltage threshold was found for devices under test (DUT). It is helpful for engineers to choose devices used in satellites. (authors)

2008-12-01

130

Satellite power systems (sps) concept definition study (Exhibit d). Volume 6, Part 1: cost and programmatics. Final report  

Energy Technology Data Exchange (ETDEWEB)

A summary of the cost data reviewed as well as conclusions and recommendations are presented. Cost and programmatic aspects of Rockwell's SPS CR-2 reference configuration were based on the results of several contracts with NASA and independent company-sponsored activities by the Space Operations and Satellite Systems Division of Rockwell International.

1981-01-01

131

Satellite power systems (SPS) concept definition study (Exhibit D). Volume 4, Part 2: cost and programmatics appendix. Final report  

Energy Technology Data Exchange (ETDEWEB)

Cost and programmatic aspects of a recommended satellite power system are documented. Computer generated summaries are presented, and the detailed computer runs structured in a Work Breakdown Structure are given. The six configurations developed during the study period are summarized.

1981-03-01

132

Satellite power systems (SPS) concept definition study (Exhibit D). Solid-state amplifier investigation. Final report  

Energy Technology Data Exchange (ETDEWEB)

Data resulting from a continuing effort to provide system/subsystem definition data to aid in the evaluation of the SPS program concept is presented. The specific data described relate to the proposed use of solid state devices as microwave power amplifiers in the satellite microwave power transmission subsystem.

1981-04-01

133

Remote sensing of mine waste. Information Circular/1987  

Energy Technology Data Exchange (ETDEWEB)

The report summarizes five separate Bureau of Mines contract studies on the use of aerial photogrammetry, satellite transmission of in situ instrumentation information, and satellite imagery to monitor and update mine waste embankment data. The equipment used, methods applied, results, recommendations, and cost analyses are presented along with a bibliography of related investigations.

1987-01-01

134

MILSTAR/FEP (FLTSATCOM EHF package) emphemeris package  

Science.gov (United States)

Design constraints require that as Earth terminal attempting communications with a FLTSATCOM EHF Package (FEP) located onboard a FLTSATCOM satellite be provided with an accurate FEP package. To be precise, the terminal is provided with a coefficient element set from which the ephemeris of a satellite may be computed. This report describes the operation of a user friendly computer program that produces the above mentioned coefficient set so as to provide reference benchmarks from which the ephemeris related operations of the terminal can be judged.

1986-08-01

135

Guarantee outline of radiation hardening for satellite  

International Nuclear Information System (INIS)

The Guarantee Outline presents the technical demands of design and contents of assessment for radiation hardening in satellite engineering in China. It includes the basis of design in space environment of polar orbit, the contents of design for general radiation hardening, the requirements and assessments of the single-board computer, the requirements of design for circuits (including hardware and software), the choices and assessments for devices, and the primary stipulations for the requirements of design and assessments against the phenomenon of charge and discharge.

136

5f-electron localization in uranium compounds  

International Nuclear Information System (INIS)

Observed 7-eV satellites in the XPS spectra of UGa_2 and other B-group compounds are shown to be due to two-hole final states as confirmed by existing Auger data. The presence of these satellites is an indication for a weak fd hybridization and, when compared to uranium--transition-metal compounds, increased 5f localization.

137

Physical characteristics of geosynchronous high power communications satellites  

International Nuclear Information System (INIS)

With the advent of the Information Superhighway, many organizations have been spurred into re-examining current spacecraft architectures to determine how the significantly higher communications capacities of the future will be accommodated. Opinion is divided on many issues in this arena, and none more so than the discussion that revolves around whether several large satellites in Geosynchronous Orbit (GEO) offer a better all-round service to the user community than a fleet of small satellites in Low Earth Orbit (LEO). Although this paper does not attempt to debate this particular issue, a clear finding of the work carried out by the author and others, was that considerable growth potential exists by simply increasing the physical size and capacity of conventional geosynchronous satellites while causing a minimal impact on existing ground systems and infrastructures. The work described here forms part of a power systems ...

138

Pair excitation in "9"0Zr  

International Nuclear Information System (INIS)

... 3 reactions mev range 10-100 neutron spectra neutrons nuclear reaction

139

Magnetic excitations in amorphous ferromagnets  

Science.gov (United States)

Neutron scattering techniques have been used to measure the static structure and magnetic excitations in amorphous magnets. Sum rules and computer models are used to discuss the relationship between the static disorder and the shape of the excitation spectrum. Polarized beam measurements of chi''(Q,E) are compared to analytical theories and computer calculations for the magnetic excitations in amorphous ferromagnets.

1978-03-01

141

Excited leptons and quarks at #gamma##gamma#/#gamma#e colliders  

International Nuclear Information System (INIS)

We discuss the search of excited leptons and quarks with spin 1/2 at #gamma##gamma# and at #gamma#e colliders. We show that #gamma##gamma# colliders have important advantages for the observation of excited leptons and quarks in comparison with ee, ep, and pp colliders discussed in previous papers. These collisions give a simple test for the chirality of the l"*l#gamma# transition. The anomalous magnetic moment of excited leptons can be observed when its value is not too small. (orig.).

146

Levels in "7"2Se observed via in-beam gamma-ray spectroscopy in the "5"8Ni("1"6O,2p) reaction  

International Nuclear Information System (INIS)

Levels in "7"2Se were observed via in-beam gamma spectroscopy following the "5"8Ni("1"6O,2p) reaction. Spectra and partial energy level schemes are shown. (3 figures) (U.S.).

1975-05-01

147

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

148

Collisional excitation transfer between lithium isotopes  

Energy Technology Data Exchange (ETDEWEB)

Excitation transfer between the 3S[sub 1/2] states of the lithium isotopes [sup 6]Li and [sup 7]Li is measured in a thermionic diode. The 3S level is excited by off-resonant two-photon transitions with a single mode cw laser. The relative densities of the directly excited and collisionally populated levels are probed by further laser excitation to the 12P levels. An energy transfer cross section of 585 A[sup 2] [+-] 160 A[sup 2] is found at the experimental temperature of about 850 K. A simple semiclassical calculation yields a cross section of 450 A[sup 2]. (orig.)

1995-01-01

149

Who's In The Dark: Satellite Based Estimates Of Electrification Rates  

Energy Technology Data Exchange (ETDEWEB)

A technique has been developed to estimate the percent population having electric power access based on the presence of satellite detected nighttime lighting. A global survey was conducted for the year 2006 using nighttime lights collected by the U.S. Air Force Defense Meteorological Satellite Program (DMSP) in combination with the U.S. Department of Energy Landscan population dataset. The survey includes results for 229 countries and more than 2000 subnational units. The results are compared to reported electrification rates for 87 countries compiled from a variety of sources by the International Energy Agency. The DMSP derived estimate of number of people worldwide who lack access to electricity is 1.62 billion, only slightly larger than the 1.58 billion estimated by the International Energy Agency.

2011-01-01

150

The Authenticated Tracking and Monitoring System (ATMS) concept  

Energy Technology Data Exchange (ETDEWEB)

The Authenticated Tracking and Monitoring System (ATMS) has been designed to address the need for global monitoring of the status and location of proliferation-sensitive items. Conceived to utilize the proposed Global Verification and Location System (GVLS) satellite link, ATMS could use the existing International Maritime Satellite commercial communication system until GVLS is operational. The ATMS concept uses sensor packs to monitor items and environmental conditions, collects a variety of events data through a sensor processing unit, and transmits the data to a satellite, which then sends data to ground stations. Authentication and encryption algorithms will be used to secure the data. A typical ATMS application would be to track and monitor the safety and security of a number of items in transit along a scheduled shipping route. This paper also discusses a possible proof-of-concept system demonstration.

1993-08-01

151

Land cover change of watersheds in Southern Guam from 1973 to 2001  

British Library Electronic Table of Contents (United Kingdom)

Land cover change can be caused by human-induced activities and natural forces. Land cover change in watershed level has been a main concern for a long time in the world since watersheds play an important role in our life and environment. This paper is focused on how to apply Landsat Multi-Spectral Scanner (MSS) satellite image of 1973 and Landsat Thematic Mapper (TM) satellite image of 2001 to determine the land cover changes of coastal watersheds from 1973 to 2001. GIS and remote sensing are integrated to derive land cover information from Landsat satellite images of 1973 and 2001. The land cover classification is based on supervised classification method in remote sensing software ERDAS IMAGINE. Historical GIS data is used to replace the areas covered by clouds or shadows in the image o...

2011-01-01

152

Analyses and monitoring of lignite mining lakes in Eastern Germany with spectral signatures of Landsat TM satellite data  

British Library Electronic Table of Contents (United Kingdom)

Coal mining activities cause an increased acidity and an associated decrease of the pH-value in mine waters. This process is also known as acid mine drainage (AMD). Due to AMD, lakes that were formed in the post mining landscapes in the lignite mining area of Central Germany are characterized by specific limnological development changes. Remote sensing is a time and cost saving technique that enables the observation of the hydrological and limnological development of the lakes ranging from a small to a mid size scale. The current research was based on Landsat TM5/ETM+7 satellite data collected between 1999 and 2004. In combination of satellite data, surface waters of the post mining lakes in Central Germany were sampled and analyzed for their physicochemical properties. The objective of th...

2011-01-01

153

A satellite born charged particles telescope for the study of cosmic ray nuclei  

Energy Technology Data Exchange (ETDEWEB)

The description of the high energy particle telescope NINA for the study of cosmic ray nuclei is presented. The instrument will be installed on board of the Resource 01 satellite and will fly on a polar orbit at 690 Km. The telescope consists on a pile of 16 detecting planes each of them is composed by two silicon strip detectors with perpendicular strips and has a total area of 60x60mm{sup 2}. The experiment goals are the study of cosmic ray protons and nuclei in the energy range 12-100 MeV/amu. It will be sensitive to the anomalous component and will also make the observation of the large solar flare events and geophysical phenomena as well. This experiment is the first step of the program RIM whose goal is the satellite study of anti particles in primary cosmic rays.

1995-09-01

154

A comparison of the UHF Follow-On and MILSTAR satellite communication systems  

Science.gov (United States)

The author compares the UHF Follow-On and MILSTAR satellite communication systems. The comparison uses an analytical hierarchy process. Although the two systems have been tasked with different missions, a comparison of cost, capability, and orbit is conducted. UFO provides many of the same capabilities as MILSTAR, but on a smaller scale. Since UFO is also a new space system acquisition, it is used to compare dollars spent to field a viable communication system. A review of frequency bands, losses, and problems is conducted to establish the relationship. Cost data is provided to establish the major difference in the systems. While MILSTAR does possess more total capability than UFO, it is 10 times more costly. Additionally, UFO is a satellite that will evolve with new technology while MILSTAR is built to full capability immediately. In the author's opinion, the incremental performance of MILSTAR does not justify its incremental cost.

1991-09-01

155

Experience with the identification and tuning of excitation system parameters at the second nuclear power plant of Taiwan Power Company  

Energy Technology Data Exchange (ETDEWEB)

Experience with the identification and tuning of exciter constants for a generating unit as the Second Nuclear Power Plant of Taiwan Power Company is reported. Field test is first performed on the excitation system with the generator open-circuited. Since the field test results differ from the computer simulation results using manufacturer`s constants, the authors first modify the manufacturer`s constants based on their previous experience to reach a preliminary set of parameters for the excitation system. Then a hybrid nonlinear simulation-sensitivity matrix method is developed to further refine the excitation system parameters. The exciter constants are tuned in order to give better dynamic response before a power system stabilizer is applied to the generator. Field tests are then performed in order to compare the dynamic response of the generator without and with power system ...

1996-05-01

156

Experience with the identification and tuning of excitation system parameters at the second nuclear power plant of Taiwan Power Company  

International Nuclear Information System (INIS)

Experience with the identification and tuning of exciter constants for a generating unit as the Second Nuclear Power Plant of Taiwan Power Company is reported. Field test is first performed on the excitation system with the generator open-circuited. Since the field test results differ from the computer simulation results using manufacturer's constants, the authors first modify the manufacturer's constants based on their previous experience to reach a preliminary set of parameters for the excitation system. Then a hybrid nonlinear simulation-sensitivity matrix method is developed to further refine the excitation system parameters. The exciter constants are tuned in order to give better dynamic response before a power system stabilizer is applied to the generator. Field tests are then performed in order to compare the dynamic response of the generator without and with power system ...

1995-07-23

157

the earth observer - Earth Observing System - NASA  

Science.gov (United States)

of satellite, aircraft and ground-based observations. In ..... swarm traps by Utah Department of Food and Agriculture (DAF) personnel. Preliminary Results ..... the 150th anniversary of the book's publication and the 200th anniversary of Darwin's birth. ...... cold war submarine missions to find that Arctic Ocean ...

158

The Harris M. Schurmeier Collection, 1970-1986 3.0 cubic ... - NASA  

Science.gov (United States)

SDI was a space-based defense system designed to ... satellites that could detect a massive nuclear launch within seconds, orbiting laser weapons to destroy the ..... AIAA Washington Conference, memorandum from T. W. Hamilton to H. ...

159

The Effect of Lunar-like Satellites on the Orbital Infrared Light Curves of Earth-analog Planets  

CERN Document Server

We investigate the influence of lunar-like satellites on the infrared orbital light curves of Earth-analog extra-solar planets. Such light curves will be obtained by NASA's Terrestrial Planet Finder (TPF) and ESA's Darwin missions as a consequence of repeat observations to confirm the companion status of a putative planet. We use an energy balance model to calculate disk-averaged infrared (bolometric) fluxes from planet-satellite systems over a full orbital period (one year). The satellites are assumed to lack an atmosphere, have a low thermal inertia like that of the Moon and span a range of plausible radii. The planets are assumed to have thermal and orbital properties that mimic those of the Earth while their obliquities and orbital longitudes of inferior conjunction remain free parameters. Even if the gross thermal properties of the planet can be independently constrained (e.g. via spectroscopy or visible-wavelength ...

2008-01-01

160

THEMIS-D - SPASE Resource Description  

Science.gov (United States)

Feb 23, 2011 ... THEMIS-D: The Solid State Telescope (SST) measures the incoming ... Each single sensor covers an angle of 36 degrees. .... The five small satellites were launched together on a Delta II rocket and they carry identical ...

161

THE STRUCTURE AND FUNCTION OF CENTRIOLES AND THEIR SATELLITES IN THE JELLYFISH PHIALIDIUM GREGARIUM  

UK PubMed Central (United Kingdom)

Testes of jellyfish Phialidium gregarium were fixed in 2 per cent OsO4 in Veronal-acetate buffer at pH 7.4. Thin sections showed that in young spermatids the spindle fibers...Full Text Available

1964-06-01

162

System Design and Applications of the Ultra Small ... - GLTRS - NASA  

Science.gov (United States)

The advanced technologies of Ka-Band systems such as high gain spot .... sometimes used based on link requirements for a specific application. .... received at NASA LeRC from a Ku-band satellite and retransmitted to the USAT at Ka-Band. .... and to the Office of Management and Budget, Paperwork Reduction Project ...

163

Sodium sulphur starts to deliver. [High power density battery  

Energy Technology Data Exchange (ETDEWEB)

The development of a high power density sodium sulphur battery with a five-year maintenance-free life is described. These batteries are likely to be used in industrial trucks, milk floats, electric cars, storing power station output and power for satellites. (U.K.).

1985-10-03

164

Satellite imagery in the study and forecast of malaria  

UK PubMed Central (United Kingdom)

More than 30 years ago, human beings looked back from the Moon to see the magnificent spectacle of Earth-rise. The technology that put us into space has since been used to assess the damage...Full Text Available

2002-02-07

165

SPASE Resource Description - the VMO - NASA  

Science.gov (United States)

THEMIS-A: The Solid State Telescope (SST) measures the incoming intensity ... units (heads), each SST unit has two pairs of opposing ion and electron sensors. .... The five small satellites were launched together on a Delta II rocket and they ...

166

Propagation Effects Handbook for Satellite Systems - DESCANSO - NASA  

Science.gov (United States)

time as well, due to the complex patterns of air movement taking place within cumulus clouds. ...... cumulative distribution of XPD, for rain and ice-particle induced ...... CCIR (1986f), Attenuation by Hydrometeors, In Particular ...

167

Prediction of a Rift Valley fever outbreak  

UK PubMed Central (United Kingdom)

El Niño/Southern Oscillation related climate anomalies were analyzed by using a combination of satellite measurements of elevated sea-surface temperatures and subsequent elevated rainfall and...Full Text Available

2009-01-20

168

Position-sensitive proportional counter for space-based X-ray imaging studies  

International Nuclear Information System (INIS)

ASTROSAT, India's first dedicated astronomy satellite is slated for launch in 2007. The primary science objective of ASTROSAT is to explore the Universe using broad-band instruments covering optical, UV, soft X-ray and hard X-ray studies

2005-03-01

169

PSDE/SAT-2: Communication system architecture study, executive summary  

Science.gov (United States)

The PSDE/SAT-2 multimission satellite designed to offer a flight opportunity to different experimental communication payloads and verify the feasibility of advanced space technologies is described. It was conceived for expriment in the framework of the European DRS (Data Relay Satellite) program thus providing intersatellite and interorbit communication links, but also experimental and preoperative services. Payloads include optical communication single access payload (LSA); S-Band single access payload; S-Band multiple access payload; land mobile experimental payload; navigation payload; 40/50 GHz communication payload; and millimeter wave propagation payload. The orbital slot and interference analysis identified a limited number of orbital positions for the mission interleaved between Eutelsat satellites (i.e., 14 deg 30 min E and 17 deg 30 min E). A coordination is required in Ku-Band with Eutelsat ...

1988-01-01

170

Multiplicity distribution of charged particles in cosmic-ray proton induced nuclear reaction  

International Nuclear Information System (INIS)

The measured result of charged multiplicity in cosmic-ray proton induced nuclear reaction from Chinese satellite emulsion is reported. The correlation of shower and heavy particles is discussed and compared with p-emulsion interactions.

1993-01-01

171

Merging of airborne gravity and gravity derived from satellite altimetry: Test cases along the coast of greenland  

DEFF Research Database (Denmark)

The National Survey and Cadastre - Denmark (KMS) has for several years produced gravity anomaly maps over the oceans derived from satellite altimetry. During the last four years, KMS has also conducted airborne gravity surveys along the coast of Greenland dedicated to complement the existing onshore gravity coverage and fill in new data in the very-near coastal area, where altimetry data may contain gross errors. The airborne surveys extend from the coastline to approximately 100 km offshore, along 6000 km of coastline. An adequate merging of these different data sources is important for the use of gravity data especially, when computing geoid models in coastal regions. The presence of reliable marine gravity data for independent control offers an opportunity to study procedures for the merging of airborne and satellite data around Greenland. Two different merging techniques, both based on collocation, are investigated in this paper. ...

2002-01-01

172

Global Environmental Data for Mapping Infectious Disease Distribution  

UK PubMed Central (United Kingdom)

This contribution documents the satellite data archives, data processing methods and temporal Fourier analysis (TFA) techniques used to create the remotely sensed datasets on the DVD distributed...Full Text Available

2006-01-01

173

GOES-12 Observes Flooding in Northeastern U.S.  

National Aeronautics and Space Administration (NASA)

This video compiles 10 days' worth of observations from the GOES-12 satellite and shows the storms that dumped heavy rainfall on the Northeastern United States in the latter part of March 2010.

2010-04-02

174

Epilogue - GES DISC - NASA  

Science.gov (United States)

Sep 9, 2009... a French Ariane rocket successfully launched a new Earth-observing satellite ... The payload is a pair of identical sensors known as "high-resolution ... the resulting image) are activated simultaneously by incoming radiation; ...

175

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

Science.gov (United States)

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

1986-01-01

176

Civil and Military Satellite Communications: A Systems ...  

Science.gov (United States)

... to-noise density than the uplink budget has (74.2 ... in heav:, point-to-point link applications with ... 11.7 Expanded bands allocated (Ku band) (500 MHz ...

1991-02-01

177

Warm waters, bleached corals  

Science.gov (United States)

Two researchers, Tom Goreau of the Discovery Laboratory in Jamaica and Raymond Hayes of Howard University, claim that they have evidence that nearly clinches the temperature connection to the bleached corals in the Caribbean and that the coral bleaching is an indication of Greenhouse warming. The incidents of scattered bleaching of corals, which have been reported for decades, are increasing in both intensity and frequency. The researchers based their theory on increased temperature of the seas measured by satellites. However, some other scientists feel that the satellites measure the temperature of only the top few millimeters of the water and that since corals lie on reefs perhaps 60 to 100 feet below the ocean surface, the elevated temperatures are not significant.

1990-10-12

178

Non-gravitational perturbations and satellite geodesy  

Energy Technology Data Exchange (ETDEWEB)

This book presents the basic ideas of the physics of non-gravitational perturbations and the mathematics required to compute their orbital effects. It conveys the relevance of the different problems that must be solved to achieve a given level of accuracy in orbit determination and in recovery of geophysically significant parameters. Selected Contents are: Orders of Magnitude of the Perturbing Forces, Tides and Apparent Forces, Tools from Celestial Mechanics, Solar Radiation Pressure-Direct Effects: Satellite-Solar Radiation Interaction, Long-Term Effects on Semi-Major Axis, Radiation Pressure-Indirect Effects: Earth-Reflected Radiation Pressure, Anisotropic Thermal Emission, Drag: Orbital Perturbations by a Drag-Like Force, and Charged Particle Drag.

1987-01-01

179

NPOESS Interface Data Processing Segment (IDPS) Hardware  

Science.gov (United States)

The National Oceanic and Atmospheric Administration (NOAA), Department of Defense (DoD), and National Aeronautics and Space Administration (NASA) are jointly acquiring the next-generation weather and environmental satellite system; the National Polar-orbiting Operational Environmental Satellite System (NPOESS). NPOESS replaces the current Polar-orbiting Operational Environmental Satellites (POES) managed by NOAA and the Defense Meteorological Satellite Program (DMSP) managed by the DoD. The NPOESS satellites carry a suite of sensors that collect meteorological, oceanographic, climatological, and solar-geophysical observations of the earth, atmosphere, and space. The NPOESS design allows centralized mission management and delivers high quality environmental products to military, civil and scientific users. The ground data processing segment for NPOESS is the Interface Data Processing ...

2008-12-01

180

Theoretical Study of Tautomerization Reactions for the Ground and First Excited Electronic States of Adenine.  

Science.gov (United States)

Geometrical structures and energetic properties for different tautomers of adenine are calculated in this study, using multi-configurational wave functions. Both the ground and the lowest singlet excited state potential energy surfaces are studied. Four t...

2002-01-01

181

Study of the reactions "1"0"4Ru(d,p)"1"0"5Ru and "1"0"0Mo(d,p)"1"0"1Mo  

International Nuclear Information System (INIS)

... reactions differential cross sections dwba excitation excited states mev range

1975-04-07

182

Rate of allosteric change in hemoglobin measured by modulated excitation using fluorescence detection.  

UK PubMed Central (United Kingdom)

We have measured the forward and reverse rates of the allosteric transition of hemoglobin A with three CO molecules bound by using modulated excitation coupled with fluorescence quenching of the DPG...Full Text Available

1989-10-01

183

Cells navigate with a local-excitation, global-inhibition-biased excitable network  

UK PubMed Central (United Kingdom)

Cells have an internal compass that enables them to move along shallow chemical gradients. As amoeboid cells migrate, signaling events such as Ras and PI3K activation occur spontaneously on pseudopodia....Full Text Available

2010-10-05

184

Acoustic transducer for acoustic microscopy  

Energy Technology Data Exchange (ETDEWEB)

A shear acoustic transducer-lens system in which a shear polarized piezoelectric material excites shear polarized waves at one end of a buffer rod having a lens at the other end which excites longitudinal waves in a coupling medium by mode conversion at selected locations on the lens.

1990-01-01

185

Rai1 duplication causes physical and behavioral phenotypes in a mouse model of dup(17)(p11.2p11.2)  

UK PubMed Central (United Kingdom)

Genomic disorders are conditions that result from DNA rearrangements, such as deletions or duplications. The identification of the dosage-sensitive gene(s) within the rearranged genomic interval is...Full Text Available

2006-11-01

186

Nrf2 increases survival and attenuates alveolar growth inhibition in neonatal mice exposed to hyperoxia  

UK PubMed Central (United Kingdom)

Increased oxidative stress is associated with perinatal asphyxia and respiratory distress in the newborn period. Induction of nuclear factor erythroid 2 p45-related factor (Nrf2) has been shown to decrease...Full Text Available

2009-04-01

187

Manufacture of PLZT Bonded Lens Assemblies.  

Science.gov (United States)

Two manufacturing processes have been developed for fabricating PLZT bonded lens assemblies (BLA's) for the USAF EEU-2/P Thermal/Flash Protective Goggle. One process utilizes thin Sylgard spacers which remain in the BLA to establish bond thickness between...

1979-01-01

188

Improving yield of industrial biomass propagation by increasing the Trx2p dosage  

UK PubMed Central (United Kingdom)

The beneficial effect of improving yeast redox response by increasing thioredoxin levels has been shown. Decreased lipid and protein oxidation is reflected in an increased biomass yield. In addition,...Full Text Available

2010-09-01

189

Acute atrial arrhythmogenicity and altered Ca2+ homeostasis in murine RyR2-P2328S hearts  

UK PubMed Central (United Kingdom)

AimsThe experiments explored for atrial arrhythmogenesis and its possible physiological background in recently developed hetero-(RyR2+/S) and homozygotic...Full Text Available

2011-03-01

190

Transition probabilities of rotational levels in "1"7"7Ta  

International Nuclear Information System (INIS)

... capture radioisotopes energy levels excited states intermediate mass nuclei

191

Spectroscopy of "1"0"1Mo by sub-Coulomb stripping  

International Nuclear Information System (INIS)

... deuteron beams differential cross sections dwba excitation functions mev range

194

RXTE Catches Morphing Magnetar  

Science.gov (United States)

This exciting new development in neutron star evolution was presented at the Winter 2004 AAS Meeting in Atlantia,Georgia. ...

195

Nuclear moments of the 11/2"- isomer in "1"8"7Ir  

International Nuclear Information System (INIS)

... excited states iridium 187 isomeric nuclei magnetic fields nuclear electric

196

Multistep contributions in "8"8Sr(h,t)"8"8Y  

International Nuclear Information System (INIS)

... mixing coupled channel theory differential cross sections excited states helium

197

Mechanism of thermal excitation of the electron states of diatomic molecules behind a shock wave front  

Energy Technology Data Exchange (ETDEWEB)

Alternative mechanisms of electron state excitation in diatomic molecules are examined with reference to CN and C2 molecules forming in chemical reactions behind strong shock wave fronts in a CO(CO2)-N2 gas mixture. The temperature range considered is 4000-8000 K. An effective excitation mechanism is proposed which involves rapid vibration-rotation excitation at all electron states and nonradiative transitions between perturbed electron states induced by collisions with the ambient gas particles.

1981-03-01

198

Investigation of W"1"7"7 decay scheme by #gamma##gamma#-coincidence method  

International Nuclear Information System (INIS)

... coincidence spectrometry decay excited states gamma spectra half-life

1973-01-29

199

Investigation of "8"8Sr by (e,e') and (p,p') reactions  

International Nuclear Information System (INIS)

... bcs theory electron reactions excited states form factors inelastic scattering

200

Excited leptons and quarks at. gamma. gamma. /. gamma. e colliders  

Energy Technology Data Exchange (ETDEWEB)

We discuss the search of excited leptons and quarks with spin 1/2 at {gamma}{gamma} and at {gamma}e colliders. We show that {gamma}{gamma} colliders have important advantages for the observation of excited leptons and quarks in comparison with ee, ep, and pp colliders discussed in previous papers. These collisions give a simple test for the chirality of the l{sup *}l{gamma} transition. The anomalous magnetic moment of excited leptons can be observed when its value is not too small. (orig.).

1992-02-06

201

Excitation Energy Transfer Study of the Spatial Relationship ...  

Science.gov (United States)

... closely correlated to the amount of re- centration. The molar extinction coefficients were agent added to the enzyme. The naphtha- ...

1988-02-15

202

Electron-induced luminescence and x-ray spectrometer development: progress report  

Science.gov (United States)

The progress in the development of a surface analysis tool based on the excitation of characteristic

2003-01-01

203

Electromagnetic excitations in nuclei: From photon scattering to photo-dissociation  

International Nuclear Information System (INIS)

... 98 target molybdenum 99 niobium 91 photoneutrons photonuclear reactions

2006-03-20

204

Duality picture between antiferromagnetism and d-wave superconductivity in t-J model at two dimensions  

Energy Technology Data Exchange (ETDEWEB)

The author shows in this paper an interesting relation between elementary and topological excitations in the antiferromagnetic and d-wave superconducting phases of the t-J model at two dimensions. The topological spin and charge excitations in one phase have the same dynamics as elementary excitations in the other phase, except the appearance of energy gaps. Moreover, the transition from one phase to another can be described as a quantum disordering transition associated with the topological excitations. Based on the above picture, a plausible phase diagram of t-J model is constructed.

2000-02-10

205

Concentrated particle-hole strength observed in 0h#omega# stretched-state excitations  

International Nuclear Information System (INIS)

The wide-angle spectra of the 134-MeV (p,n) reaction on "4"8Ca, "5"4Fe, "8"8Sr, and "2"0"8Pb are each dominated by the excitation of a single state at low excitation energy. These excitations correspond to the ''0h#omega#'' stretched states and are seen to be fragmented much less than ''1h#omega#'' stretched states in medium- and heavy-mass nuclei. The normalization factors required for comparison with distorted-wave impulse-approximation calculations are >0.50 and indicate that these are the purest particle-hole states known in these nuclei.

206

#beta#-delayed proton decays of "8"1Zr and "8"5Mo  

International Nuclear Information System (INIS)

... RADIATION PHYSICS beta decay delayed protons excited states experimental

207

The use of the isotope "3"2P in the study of some ecological aspects of a laboratory stream ecosystem  

International Nuclear Information System (INIS)

A laboratory stream consisting of two stream sections interrupted by two pools was filled with a mixture of tap water and organically enriched water from rivers nearby. Bottom sediment material, Potamogeton pectinatus, macro-invertebrate organisms, as well as the mosquito fish, Aplocheilichthys johnstonii were collected from rivers around Johannesburg and introduced into the laboratory stream. After initial acclimatization, the distribution of the isotope "3"2P through this laboratory stream was followed. Absorption of this isotope by benthic algae, Potamogeton pectinatus, several macro-invertebrate organisms as well as Aplocheilichthys johnstonii was recorded.

208

The 2s{sup 1}2p{sup 4} autodetachment resonance in the C{sup -} negative ion  

Energy Technology Data Exchange (ETDEWEB)

The calculations of the photodetachment cross section for the C{sup -} negative ion has been performed within the newly-developed many-body theory method, the RPAE interchannel interaction and dynamic relaxation and polarization corrections being included. The 2s{sup 1}2p{sup 4} shape resonance is shifted to a higher photon energy and broadens as compared to the resonance parameters determined earlier within the RPAE, which is consistent with the experimental evidence and the recent R-matrix calculations. (orig.) 18 refs.

1998-08-10

209

Serial multivibrator on field effect transistors  

International Nuclear Information System (INIS)

An operating cycle of a serial multivibrator carried out on the base of field-effect transistors has been analyzed. Calculation relations for the main multivibrator parameters have been obtained, and conditions of self-excitation has been determined. Experimental data for determination of the self-oscillation excitation region have been presented. These results are in a good agreement with the experiment. The analysis of the data obtained has shown that the serial multivibrator on field-effect transistors has comparatively narrow excitation region and requires an accurate turning.

210

Photoaffinity labeling of ATP and NAD"+ binding sites on recombinant human interleukin 2  

International Nuclear Information System (INIS)

Interleukin 2 (IL-2) is a T-cell-derived lymphokine critical in the activation and proliferation of T cells, B cells, and lymphokine-activated killer cells. It is a glycoprotein of #approx#15,500 daltons that is synthesized and secreted after activation by antigen or mitogen. By using the analogs 8-azidoadensoine 5'-[#gamma#-"3"2P]triphosphate ([#gamma#-"3"2P]8N_3ATP) and nicotinamide 2-azidoadenine [adenylate-"3"2P]dinucleotide ([#alpha#-"3"2P]2N_3NAD"+) as photoaffinity probes, the authors have detected specific, metal ion-requiring nucleotide binding sites on recombinant human IL-2 (rhIL-2). The specificity of these nucleotide interactions with rhIL-2 was demonstrated by saturation effects and by competition by the parent nucleotides at physiologically relevant concentrations. Saturation of photoinsertion into rhIL-2 ...

211

ALOS satellite imagery utilizations for safeguards  

International Nuclear Information System (INIS)

This paper introduces examples of satellite imageries analysis and utilizations for safeguards activities. Recently, many kinds of satellite imageries are available in the world i.e., high-spatial resolution, multi- and hyper-spectral, multi-function, and multi-polarization radars. The problem is that how to obtain the required information from these digital images. The Japan Aerospace Exploration Agency (JAXA) has successfully launched the Advanced Land Observing Satellite (ALOS, the nickname is 'Daichi') on 24th January, 2006. The mission objectives are cartography, regional observation, disaster monitoring etc. ALOS has three instruments, PRISM, AVNIR-2, and PALSAR, to achieve these objectives. An overview of ALOS is provided. ALOS follows the Japanese Earth Resources Satellite- 1 (JERS-1) and the Advanced Earth Observing Satellite (ADEOS) and utilizes advanced land-observing ...

2006-10-16

212

Up-conversion luminescence saturation under pulsed excitation of erbium-doped, SiO_2-TiO_2 sol-gel powders  

International Nuclear Information System (INIS)

The intensity of erbium up-conversion luminescence could be limited by a saturation effect due to increased pump power. We studied the luminescence saturation of the 550 nm emission on erbium-doped, SiO_2-TiO_2 sol-gel powders under pulsed excitation at 979 and 1532 nm. From the latter, the up-converted luminescence intensity decreased with increasing excitation power, whereas no saturation was observed at 979 nm excitation. We proposed that the saturation effect is determined by the pump power, the erbium content and the lifetime of the corresponding first excited states at different pumping schemes.

2010-12-01

213

Influence of excited molecules on electron swarm transport coefficients and gas discharge kinetics  

Energy Technology Data Exchange (ETDEWEB)

In this paper we study different effects of excited molecules on swarm parameters, electron energy distribution functions and gas discharge modeling. First we discuss a possible experiment in parahydrogen to resolve the discrepancy in hydrogen vibrational excitation cross section data. Negative differential conductivity (NDC) is a kinetic phenomenon which manifests itself in a particular dependence of the drift velocity on E=N and it is affected by superelastic collisions with excited states. A complete kinetic scheme for argon required to model excited state densities in gas discharges is also described. These results are used to explain experiments in capacitively and inductively coupled RF plasmas used for processing. The paper illustrates the application of atomic and molecular collision data, swarm data and the theoretical techniques in modeling of gas discharges with large abundances of ...

1997-09-01

214

An analysis strategy for safeguards use of optical satellite imagery  

International Nuclear Information System (INIS)

This paper outlines conceptual framework for safeguards remote sensing, and suggests a strategy for overcoming the challenges to full exploitation of all types of optical satellite imagery. Since the introduction of commercial open-source high-resolution satellite imagery in 1999, it has become an important tool for verification of declarations, baseline mapping, detection and monitoring of changes and investigation of undeclared activities. Its use is still relatively restricted, but there is a growing demand for wider satellite reconnaissance support, and the Satellite Image Analysis Unit (SIAU) has recently been expanded in response. For a number of reasons, IAEA safeguards use of satellite imagery is largely based on visual interpretation by experienced image analysts of high-resolution monochromatic imagery to monitor and characterize buildings and structures on safeguards ...

2006-10-16

215

Design and integration of a solar AMTEC power system with an advanced global positioning satellite  

Energy Technology Data Exchange (ETDEWEB)

A 1,200-W solar AMTEC (alkali metal thermal-to-electric conversion) power system concept was developed and integrated with an advanced global positioning system (GPS) satellite. The critical integration issues for the SAMTEC with the GPS subsystems included (1) packaging within the Delta 2 launch vehicle envelope, (2) deployment and start-up operations for the SAMTEC, (3) SAMTEC operation during all mission phases, (4) satellite field of view restrictions with satellite operations, and (5) effect of the SAMTEC requirements on other satellite subsystems. The SAMTEC power system was compared with a conventional planar solar array/battery power system to assess the differences in system weight, size, and operations. Features of the design include the use of an advanced multitube, vapor anode AMTEC cell design with 24% conversion efficiency, and a direct solar insolation receiver design with integral LiF ...

1996-12-31

216

Photodissociation dynamics of doubly excited Rydberg states of molecular hydrogen  

International Nuclear Information System (INIS)

We have applied photofragment ion imaging to investigate the dissociation dynamics of low-lying, doubly excited states of molecular hydrogen. A doubly excited electronic state is one in which both of the hydrogen electrons reside in excited molecular orbitals. Two-step, two-color multiphoton excitation of H_2, first via 201.8 nm, two-photon excitation into the E, F "1#SIGMA#"+_g(v_E=0, J=1) state, followed by #approx#563 nm, 1+m (m=1, 2) excitation through the B double-prime "1#SIGMA#"+_u(v=0, J=0, 2), D "1#PI#_u(v=2, J=1, 2), and B' "1#SIGMA#"+_u(v=4, J=0, 2) states provides a ready means of populating several low-lying doubly excited states of H_2 at increasing internuclear separations. From these doubly excited repulsive states, both dissociation and autoionization processes are possible. Because the ...

217

Mapping of the nucleotide-binding sites in the ADP/ATP carrier of beef heart mitochondria by photolabeling with 2-azido[#alpha#-"3"2P]adenosine diphosphate  

International Nuclear Information System (INIS)

2-Azido[#alpha#-"3"2P]adenosine diphosphate (2-azido[#alpha#-"3"2P]ADP) has been used to photolabel the ADP/ATP carrier in beef heart mitochondria. In reversible binding assays carried out in the dark, this photoprobe was found to inhibit ADP/ATP transport in beef heart mitochondria and to bind to two types of specific sites of the ADP/ATP carrier characterized by high-affinity binding (K/sub d/ = 20 #mu#M) and low-affinity binding (K/sub d/ = 400 #mu#M). In contrast, it was unable to bind to specific carrier sites in inverted submitochondrial particles. Upon photoirradiation of beef heart mitochondria in the presence of 2-azido[#alpha#-"3"2P]ADP, the ADP/ATP carrier was covalently labeled. After purification, the photolabeled carrier protein was cleaved chemically by acidolysis or cyanogen bromide and enzymatically with the Staphylococcus aureus V8 protease. In ...

218

The Pamela Cosmic Ray Space Observatory: Detector, Objectives and First Results  

CERN Document Server

PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature in a wide energy range (protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50 MeV-270 GeV) and search for antimatter with a precision of the order of $10^{-8}$). The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June, 15 2006 in a $350\\times 600 km$ orbit with an inclination of 70 degrees. The detector is composed of a series of scintillator counters arranged at the extremities of a permanent magnet spectrometer to provide charge, Time-of-Flight and rigidity information. Lepton/hadron identification is performed by a Silicon-Tungsten calorimeter and a Neutron detector placed at the bottom of the device. An Anticounter system is used offline to reject false triggers coming from the ...

2009-01-01

219

Mid-latitude scintillation model. Technical report, 1 November 1985-31 October 1986  

Energy Technology Data Exchange (ETDEWEB)

Radiowave scintillation in the presence of ionospheric disturbances has the potential to disrupt numerous transionospheric radio and radar systems. This report describes development of a model characterizing the plasma density irregularities that produce scintillation in the naturally disturbed mid-latitude F layer. The model will be incorporated into Program WBMOD, which includes subroutines for computing both link geometry and scintillation indices, the latter by means of phase screen diffraction theory. Earlier versions of WBMOD, were based on extensive analysis of scintillation data collected in the auroral and equatorial zones in Wideband Satellite Mission. The model described herein is based on similarly extensive analysis of Wideband data from one mid latitude station and of data collected from HiLat satellite at another mid latitude station. The model describes irregularities at an effective height of 350 km that are isotropic across ...

1986-10-31

220

Local Group Dwarf Galaxies: Nature And Nurture  

CERN Document Server

We investigate the formation and evolution of dwarf galaxies in a high resolution, hydrodynamical cosmological simulation of a Milky Way sized halo and its environment. Our simulation includes gas cooling, star formation, supernova feedback, metal enrichment and UV heating. In total, 90 satellites and more than 400 isolated dwarf galaxies are formed in the simulation, allowing a systematic study of the internal and environmental processes that determine their evolution. We find that 95% of satellite galaxies are gas-free at z=0, and identify three mechanisms for gas loss: supernova feedback, tidal stripping, and photo-evaporation due to re-ionization. Gas-rich satellite galaxies are only found with total masses above ~ 5x10^9 solar masses. In contrast, for isolated dwarf galaxies, a total mass of ~ 10^9 solar masses constitutes a sharp transition; less massive galaxies are predominantly gas-free at z=0, more massive, ...

2011-01-01

221

Launch of the Space experiment PAMELA  

CERN Document Server

PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature in a wide energy range protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50 MeV-270 GeV) and search for antimatter with a precision of the order of 10^-8). The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June, 15, 2006 in a 350*600 km orbit with an inclination of 70 degrees. The detector is composed of a series of scintillator counters arranged at the extremities of a permanent magnet spectrometer to provide charge, Time-of-Flight and rigidity information. Lepton/hadron identification is performed by a Silicon-Tungsten calorimeter and a Neutron detector placed at the bottom of the device. An Anticounter system is used offline to reject false triggers coming from the ...

2007-01-01

222

He-like ions as practical astrophysical plasma diagnostics: From stellar coronae to active galactic nuclei  

CERN Document Server

We review X-ray plasma diagnostics based on the line ratios of He-like ions. Triplet/singlet line intensities can be used to determine electronic temperature and density, and were first developed for the study of the solar corona. Since the launches of the X-ray satellites Chandra and XMM-Newton, these diagnostics have been extended and used (from CV to Si XIII) for a wide variety of astrophysical plasmas such as stellar coronae, supernova remnants, solar system objects, active galactic nuclei, and X-ray binaries. Moreover, the intensities of He-like ions can be used to determine the ionization process(es) at work, as well as the distance between the X-ray plasma and the UV emission source for example in hot stars. In the near future thanks to the next generation of X-ray satellites (e.g., Astro-H and IXO), higher-Z He-like lines (e.g., iron) will be resolved, allowing plasmas with higher temperatures and densities to be probed. Moreover, the ...

2011-01-01

223

Zone mapping application for precision-farming: a decision support tool for variable rate application  

British Library Electronic Table of Contents (United Kingdom)

A web-based decision support tool, zone mapping application for precision farming (ZoneMAP, External Reference Not Shown ), has been developed to automatically determine the optimal number of management zones and delineate them using satellite imagery and field data provided by users. Application rates, such as of fertilizer, can be prescribed for each zone and downloaded in a variety of formats to ensure compatibility with GPS-enabled farming equipment. ZoneMAP is linked to Digital Northern Great Plains, a web-based application which hosts an archive of satellite imagery, as well as high resolution imagery from airborne sensors. Management zones created by ZoneMAP mapped natural variation of the soil organic matter and other nutrients relatively well and were consistent with zone maps cre...

2010-01-01

224

Two years of flight of the Pamela experiment: results and perspectives  

CERN Document Server

PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature in a wide energy range (protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50 MeV-270 GeV) and search for antinuclei with a precision of the order of $10^{-8}$). The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June, $15^{th}$ 2006 in a $350\\times 600 km$ orbit with an inclination of 70 degrees. In this work we describe the scientific objectives and the performance of PAMELA in its first two years of operation. Data on protons of trapped, secondary and galactic nature - as well as measurements of the December $13^{th}$ 2006 Solar Particle Event - are also provided.

2008-01-01

225

The PAMELA space experiment: first year of operation  

Energy Technology Data Exchange (ETDEWEB)

On the 15th of June 2006 the PAMELA experiment, mounted on the Resurs DK1 satellite, was launched from the Baikonur cosmodrome and it has been collecting data since July 2006. PAMELA is a satellite-borne apparatus designed to study charged particles in the cosmic radiation, to investigate the nature of dark matter, measuring the cosmic-ray antiproton and positron spectra over the largest energy range ever achieved, and to search for antinuclei with unprecedented sensitivity. The apparatus comprises a time-of-flight system, a silicon-microstrip magnetic spectrometer, a silicon-tungsten electromagnetic calorimeter, an anticoincidence system, a shower tail catcher scintillator and a neutron detector. The combination of these devices allows charged particle identification over a wide energy range.

2008-05-15

226

Satellite-based estimates of groundwater storage variations in large drainage basins with extensive floodplains  

British Library Electronic Table of Contents (United Kingdom)

This study presents monthly estimates of groundwater anomalies in a large river basin dominated by extensive floodplains, the Negro River Basin, based on the synergistic analysis using multisatellite observations and hydrological models. For the period 2003-2004, changes in water stored in the aquifer is isolated from the total water storage measured by GRACE by removing contributions of both the surface reservoir, derived from satellite imagery and radar altimetry, and the root zone reservoir simulated by WGHM and LaD hydrological models. The groundwater anomalies show a realistic spatial pattern compared with the hydrogeological map of the basin, and similar temporal variations to local in situ groundwater observations and altimetry-derived level height measurements. Results highlight th...

2011-01-01

227

Satellite power study (SPS) concept definition study (exhibit D). Volume 1: executive summary. Final report  

Energy Technology Data Exchange (ETDEWEB)

Efforts concentrated on updating of the Rockwell reference concept, definition of new system options, studies of special emphasis topics, further definition of the transportation system, and further program definition. The Rockwell reference satellite concept has a gallium arsenide (GaAs) solar cell array having flat concentrators with an effective concentration ratio of 1.83at end of life. Alternatives to this concept includes solid state power amplifiers or magnetrons for dc/RF conversion and multibandgap solar cells for solar to dc energy conversion. Two solid state concepts were studied. It was determined that the magnetron approach was the lowest mass and cost system.

1981-03-01

228

Satellite monitoring of climatic factors regulating phytoplankton variability in the Arabian (Persian) Gulf  

British Library Electronic Table of Contents (United Kingdom)

Possible factors regulating phytoplankton variability in the Arabian (Persian) Gulf were analyzed on the basis of satellite observations and meteorological data (1997-2009), including remotely-sensed chlorophyll a concentration (CHL), sea surface temperature, wind, solar radiation, precipitation, and aerosols. Shallow waters of northwestern Gulf influenced by Shatt Al-Arab River discharge were more productive than open Gulf waters, although seasonal CHL patterns in this and other shallow regions looked unrealistic likely because the CHL signal was obscured by bottom reflection. Therefore our further analyses focused on the open Gulf waters, which show a subtropical seasonal CHL cycle with maximum in winter and minimum in spring-summer. This cycle, however, was decoupled from the seasonal e...

2010-01-01

229

Proceedings of the 23rd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting  

Energy Technology Data Exchange (ETDEWEB)

A compilation of technical papers, from the 23rd annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting, is presented. Papers were given in the following categories: (1) developments in rubidium, cesium, and hydrogen-based frequency standards, and in cryogenic and trapped-ion technology; (2) international and transnational applications of PTTI technology with emphasis on satellite laser tracking networks, GLONASS timing, comparison of national time scales and international communications; (3) applications of PTTI technology to the telecommunications, power distribution, platform positioning, and geophysical survey industries; (4) applications of PTTI technology to evolving military communications and navigation systems; and (5) dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, Loran, and synchronous communications satellites.

1992-07-01

230

Particle and X-ray damage in pn-CCDs  

Energy Technology Data Exchange (ETDEWEB)

The fully depleted pn-junction charge coupled device (pn-CCD) has been developed as a detector for X-ray imaging and high-resolution spectroscopy for the X-ray satellite missions XMM and ABRIXAS. If the detector is exposed to a particle radiation environment, the energy resolution is degraded due to charge transfer losses and a dark current increase. In a first experiment, prototype devices were irradiated with 10 MeV protons. After completion of the detector development, the proton irradiation was repeated for a quantitative study of the radiation damage, relevant for the satellite missions. The irradiation test was extended by a 5.5 MeV {alpha}-particle and a 6 keV X-ray exposure of the pn-CCD, including the CAMEX preamplifier chip.

2000-01-11

231

Multiphase origin of the Cu-Co ore deposits in the western part of the Lufilian fold-and-thrust belt, Katanga (Democratic Republic of Congo)  

British Library Electronic Table of Contents (United Kingdom)

A multiphase origin of the Cu-Co ores in the western part of the Lufilian fold-and-thrust belt in Central Africa is proposed based on literature, satellite image interpretations and petrographic and fluid inclusion analyses on samples from the stratiform mineralization of Kamoto and Musonoi (DR Congo). The various mineral occurrences in the Katanga Copperbelt can be classified in distinct categories: stratiform, supergene enrichment and vein-type. The stratiform mineralization form the largest group and can be found mainly in Lower Roan (R-2) rocks, which can be identified as ridges on satellite imagery. Ore deposits outside the R-2 occur along lineaments and result often from supergene enrichment.The main phase of the stratiform mineralization in the Katanga Copperbelt occurred during dia...

2006-01-01

232

Monitoring environmental impacts of surface coal mining  

Energy Technology Data Exchange (ETDEWEB)

Coal mining generates a number of significant environmental impacts. Due to its synoptic coverage and repetitive data acquisition capabilities, remote sensing has been extensively used to monitor effects of surface mining. Availability of low cost and high resolution data in recent years has focused increased attention on the use of satellite data for monitoring surface mining activity. This article presents an overview of some of the important studies that have used satellite and airborne remote sensing data to assess environmental impacts of coal mining and to monitor reclamation activities. Detection and delineation of subsurface coal mine fires using remotely-sensed thermal data is also briefly discussed. The utility of interfacing remote sensing and Geographic Information Systems for effective environmental management of mining areas has been emphasized.

1993-04-01

233

Investigation of GPS/IMU Positioning System for Mining Equipment  

Energy Technology Data Exchange (ETDEWEB)

The objective of this project is to investigate the applicability of a combined Global Positioning System and Inertial Measurement Unit (GPS/IMU) for information based displays on earthmoving machines and for automated earthmoving machines in the future. This technology has the potential of allowing an information-based product like Caterpillar's Computer Aided Earthmoving System (CAES) to operate in areas with satellite shading. Satellite shading is an issue in open pit mining because machines are routinely required to operate close to high walls, which reduces significantly the amount of the visible sky to the GPS antenna mounted on the machine. An inertial measurement unit is a product, which provides data for the calculation of position based on sensing accelerations and rotation rates of the machine's rigid body. When this information is coupled with GPS it results in a positioning system that can maintain positioning ...

2006-09-13

234

Emerging trends in information and communication technology in mine safety and disaster management  

British Library Electronic Table of Contents (United Kingdom)

There is tremendous growth in the use of Geographic Information Systems (GIS), Global Positioning Systems (GPS), Remote Sensing, Satellite Communication, and Modeling & Simulation techniques. These tools and techniques helps significantly in characterizing infrastructure, risk area and disaster zones, planning and implementation of hazards reduction measures etc. Communication satellites becomes vital for providing emergency communication and timely relief measures. Integration of space technology inputs into natural disaster monitoring and mitigation mechanisms is critical for hazard reduction. This paper mainly focused on all the issues described above. Major emphasis had been given to the recent developments in information & communication technology enabled tools and their applications ...

2010-01-01

235

Combining satellite data and models to estimate cloud radiative effect at the surface and in the atmosphere  

British Library Electronic Table of Contents (United Kingdom)

Abstract Satellite measurements and numerical forecast model reanalysis data are used to compute an updated estimate of the cloud radiative effect on the global multi-annual mean radiative energy budget of the atmosphere and surface. The cloud radiative cooling effect through reflection of short wave radiation dominates over the long wave heating effect, resulting in a net cooling of the climate system of - 21 Wm-2. The short wave radiative effect of cloud is primarily manifest as a reduction in the solar radiation absorbed at the surface of - 53 Wm-2. Clouds impact long wave radiation by heating the moist tropical atmosphere (up to around 40 Wm-2 for global annual means) while enhancing the radiative cooling of the atmosphere over other regions, in particular higher latitudes and sub-trop...

2011-01-01

236

Bioinformatic analysis of BBTV satellite DNA in Hainan  

British Library Electronic Table of Contents (United Kingdom)

Banana bunchy top virus (BBTV), family Nanaviridae, genus Babuvirus, is a single stranded DNA virus (ssDNA) that causes banana bunchy top disease (BBTD) in banana plants. It is the most common and most destructive of all viruses in these plants and is widespread throughout the Asia-Pacific region. In this study we isolated, cloned and sequenced a BBTV sample from Hainan Island, China. The results from sequencing and bioinformatics analysis indicate this isolate represents a satellite DNA component with 12 DNA sequences motifs. We also predicted the physical and chemical properties, structure, signal peptide, phosphorylation, secondary structure, tertiary structure and functional domains of its encoding protein, and compare them with the corresponding quantities in the replication initiatio...

2011-01-01

237

A new strategy of counterattacking anti-satellite based on motion camouflage  

Science.gov (United States)

Motion Camouflage (MC) is illuminated as a novel strategy in counterattacking anti-satellite by way of stealth trajectory scheduling. The dynamics model of MC in space is developed and a quadratic function with three boundary constraints is employed for trajectory determination. Based on the model a scenario is set to run the simulation. The results indicate given the designed acceleration input, the predator will be moved following a prescribed route, which precisely locates the predator between two objects at each time instant. In the last approaching phase, the motion is achieved with a big bumping rate which guarantees the power of this striking. Methods for deriving minimum fuel cost in the fixed approaching duration and the minimum approaching duration in limited acceleration input are proposed and are verified in the simulation. At last, camouflage is recognized as a multi-faceted affair, in which stealth trajectory design is considered an effective ...

2010-08-01

238

1982 International Geoscience and Remote Sensing Symposium, Munich, West Germany, June 1-4, 1982, Digest. Volumes 1 and 2  

Energy Technology Data Exchange (ETDEWEB)

Theoretical and experimental data which have defined and/or extended the effectiveness of remote sensing operations are explored, with consideration given to both scientific and commercial activities. The remote sensing of soil moisture, the sea surface, and oil slicks is discussed, as are programs using satellites for studying geodynamics and geodesy, currents and waves, and coastal zones. NASA, Canadian, and Japanese radar and microwave passive and active systems are described, together with algorithms and techniques for image processing and classification. The SAR-580 project is outlined, and attention is devoted to satellite applications in investigations of the structure of the atmosphere, agriculture and land use, and geology. Design and performance features of various optical scanner, radar, and multispectral data processing systems and procedures are detailed.

1982-01-01

239

A Robust and Efficient Trust Management Scheme for Peer-to-Peer Networks  

CERN Document Server

Studies on the large scale peer-to-peer (P2P) network like Gnutella have shown the presence of large number of free riders. Moreover, the open and decentralized nature of P2P network is exploited by malicious users who distribute unauthentic or harmful contents. Despite the existence of a number of trust management schemes in the literature for combating against free riding and distribution of malicious files, these mechanisms are not scalable due to their high computational, communication and storage overhead. These schemes also do not consider effect of trust management on quality-of-service (QoS) of the search. This paper presents a trust management scheme for P2P networks that minimizes distribution of spurious files by a novel technique called topology adaptation. It also reduces search time since most of the queries are resolved within the community of ...

2010-01-01

240

Vortex-Excited Vibrations of Uniform Pivoted Cylinders in Uniform and Shear Flow  

Science.gov (United States)

The vortex-excited dynamics of a uniform pivoted cylinder in uniform and sheared flow was investigated experimentally. The experiments were numerically simulated using a diffusive Van der Pol oscillator model developed by Balasubramanian & Skop recently. Salient features of the experimental investigations and the numerical simulations are presented here. Comparisons between the experimentally recorded and numerically predicted structural response to vortex-excited vibrations, power spectral density measurements of near-wake velocity fluctuations and lock-in ranges are made. A comparison of the numerical predictions and the experimental data reveals good agreement.

2000-01-01

241

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

242

Study of d+#ALPHA# system in kinematically complete experiment at 27,2 MeV #alpha#-particle energy  

International Nuclear Information System (INIS)

The "2H(#alpha#,p#alpha#)n reaction was investigated in a kinematically complete experiment with a #alpha#-beam at energy 27.2 MeV.The "5He excited state was observed and its parameters were determinate.Coincidence spectra were fitted by contribution of sequential decay through the "5He ground and excited states.The best agreement with the data was obtained assuming the following "5He excited state parameters: E_a_n=2.8 MeV #GAMMA#=2.5 MeV.

243

Signal simulator for the calibration of eddy current probes  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a signal simulator which is designed to calibrate eddy current probes. By using simultaneously an excitation coil and an electrically conducting plane, the simulator can emulate signals which correspond to spot welds with different flaws. The presence of a conducting plane allows a wide variation of the amplitude and phase of the excitation coil voltage during the calibration of a probe. A mathematical model for the simulator is derived and used to study the variation of the impedance change upon the parameters of the probe. Numerical computation shows that the impedance change depends in an important way on the frequency of the excitation coil current.

1994-01-01

244

Response of a magneto-rheological fluid damper subjected to periodic forcing in a high frequency limit  

British Library Electronic Table of Contents (United Kingdom)

We have explored vibrations of a single-degree of freedom oscillator with a magneto-rheological damper subjected to kinematic excitations in a high frequency limit. Using fast and slow scales decoupling procedure we derived an effective damping coefficient in the limit of high frequency excitation. Damping characteristics, as functions of velocity, change considerably especially by terminating the singular non-smoothness points. This effect was more transparent for a larger control parameter which was defined as the product of the excitation amplitude and its frequency.

2008-01-01

245

Plasma Dynamics in the Vicinity of the Local Plasma resonance Point Excited by Pumping Electric Field or Modulated Electron Beam  

International Nuclear Information System (INIS)

Excitation of the HF electric field in the local plasma resonance region (LPRR) of inhomogeneous plasma by pumping electric field or modulated electron beam results to appearance of the ponderomotive force that presses plasma out of this region. Density cavity is formed in the LPRR due to this field. Further dynamics in this region depends on the plasma properties. For plasma with hot electrons ion-acoustic pulses run away from the cavity. at the local density maximum the new peak of electric field is excited. It results to the formation of new density cavity, etc. For isothermal plasma the density jump is formed.

2006-01-01

246

Phonon damping by and Raman scattering from interband electronic excitations in normal and superconducting A-15 compounds  

International Nuclear Information System (INIS)

Raman scattering measurements of the Esub(g) and Tsub(2g) optical phonons in V"3Si, Nb"3Sn, V"3Ge, Cr"3Si, V"3Pt, and Nb"3Pt are presented and discussed in terms of interaction with interband electronic excitations. Data on superconducting Nb"3Sn is presented and modifications to the phonon spectral function and the spectrum of Raman active interband electronic excitations in the superconducting state are discussed. (orig.).

247

Optical properties of excitation spectra of (Ca,Y)-#alpha#-SiAlON:Eu yellow phosphors  

International Nuclear Information System (INIS)

Elemental substitution of Ca by Y was investigated for Ca-#alpha#-SiAlON:Eu yellow phosphors, which is useful for the white light-emitting diode lamps of phosphor conversion type. Depending on the ratio of the elemental substitution, not only the red shift of emission in wavelength occurred but also the figure of the excitation spectra changed. Their excitation band widths and flatness were discussed. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

2006-09-01

248

On some mechanisms of 27.2 MeV #alpha#-particle interaction with carbon nuclei  

International Nuclear Information System (INIS)

Using U-120 cyclotron in the course of correlation experiment one studied mechanisms of excitation and decay of "1"2C nucleus states resulting from irradiation of deuterium-polyethylene target by 27.2 MeV energy #alpha#-particle beam via recording of #alpha#-#alpha#-coincidence simultaneously with investigations of #alpha# + d-interactions. Production of "1"2C excited states decaying with the escape of #alpha#-particle and "8Be nucleus in the ground and the excited states is the basic mechanism of the studied #alpha# + "1"2C interaction

2001-05-01

249

Measurements of "8"8Sr(p,n) to the ground state and low-lying excited states of "8"8Y  

International Nuclear Information System (INIS)

The (p,n) cross section on "8"8Sr was measured for proton energies between 5.75 and 11 MeV. Overall resolution was sufficient to separate the "8"8Y ground state (J/sup #pi#/ = 4"-), the first excited state (J/sup #pi#/ = 5"-) at 0.232 MeV, and the second excited state (J/sup #pi#/ = 1"+) at 0.393 MeV. A Legendre polynomial fit was made to the angular distributions and the resulting integrated cross sections are shown. 1 figure.

1980-03-13

250

K_#beta#/K_#alpha# X-ray intensity ratio following K-electron capture and radioisotope excitation  

International Nuclear Information System (INIS)

The K_#beta#/K_#alpha# X-ray intensity ratios are measured for Mn and Fe and for six other elements with Z lying in the range 49<=Z<=82 following electron capture decay and photon excitation using "2"4"1Am and "5"7Co sources. High-resolution Si(Li) and HpGe detector systems were used in the experiments. The dependence of K_#beta#/K_#alpha# values on the mode of excitation in the case of Mn and Fe is attribuited to the chemical effects, while no such dependence is found for the high-Z elements.

1987-01-01

251

Excitation of 1/sup +/ states in /sup 88/Sr by proton inelastic scattering  

Energy Technology Data Exchange (ETDEWEB)

In a (p,p') study of /sup 88/Sr at Esub(p) = 201 MeV both a large resonance centered at 9.4 MeV excitation energy and the known 1/sup +/ state at 3.486 MeV are excited. Several discrete states are observed in the resonance. The cross section of the whole resonance is 27% of a simple particle-hole prediction. The strength of the low-lying 1/sup +/ state is only about 15% of that calculated from a wave function including core-polarization contributions, whereas (e,e') scattering finds about 50%.

1985-06-10

252

Excitation of 1"+ states in "8"8Sr by proton inelastic scattering  

International Nuclear Information System (INIS)

In a (p,p') study of "8"8Sr at Esub(p) = 201 MeV both a large resonance centered at 9.4 MeV excitation energy and the known 1"+ state at 3.486 MeV are excited. Several discrete states are observed in the resonance. The cross section of the whole resonance is 27% of a simple particle-hole prediction. The strength of the low-lying 1"+ state is only about 15% of that calculated from a wave function including core-polarization contributions, whereas (e,e') scattering finds about 50%. (orig.).

253

Emission and excitation spectra of feldspar inclusions within quartz  

Energy Technology Data Exchange (ETDEWEB)

Emission spectra obtained for three irradiated granular quartz samples under 1.43 eV excitation exhibited the 2.2 and 3.1 eV emission bands characteristic of feldspars. Excitation spectra of these same samples and several others show the 1.44 eV resonance typical of feldspars. This provides convincing evidence that the 2.2 and 3.1 eV infrared stimulated luminescence observed in these granular quartz samples arises from feldspar inclusions.

2004-02-01

254

Collective charge excitation of Sr_1_4_-_xCa_xCu_2_4O_4_1. A fingerprint of novel charge ordered state?  

International Nuclear Information System (INIS)

We review recent progress on experimental studies of collective charge excitations in hole-doped spin ladder system Sr_1_4_-_xCa_xCu_2_4O_4_1, focusing on anomalous features of phase excitation. We also discuss possible candidates for related charge ordered state, together with a controversial issue of the hole density transferred from spin chain layers to spin ladder layers. (author)

2007-04-01

255

Two and 8-azido photoaffinity probes. 1. Enzymatic synthesis, characterization, and biological properties of 2- and 8-azido photoprobes of 2-5A and photolabeling of 2-5A binding proteins  

International Nuclear Information System (INIS)

The 2- and 8-azido trimer 5'-triphosphate photoprobes of 2-5A have been enzymatically synthesized from [#gamma#-"3"2P]2-azidoATP and [#alpha#-"3"2P]8-azidoAPT by 2-5A synthetase from rabbit reticulocyte lysates. Identification and structural determination of the 2- and 8-azido adenylate trimer 5'-triphosphates were accomplished by enzymatic hydrolyses with T2 RNase, snake venom phosphodiesterase, and bacterial alkaline phosphatase. Hydrolysis products were identified by HPLC and PEI-cellulose TLC analyses. The 8-azido photoprobe of 2-5A displaces p_3A_4["3"2P]pCp from RNase L with affinity equivalent to p_3A_3. The 8-azido photoprobe also activates RNase L to hydrolyze poly(U)["3"2P]pCp 50% at 7 /times/ 10/sup /minus/9/ M in core-cellulose assays. The 2- and 8-azido photoprobes and authentic p_3A_3 activate RNase L to ...

256

x - NASA Technical Reports Server  

Science.gov (United States)

Mar 1, 2011 ... Radionuclide X-ray fluorescence analysis. 2: Detection of the X-ray fluorescence radiation excited by radionuclide radiation ...

257

Vibratory Dynamics of Flow-Excited Struts in Water  

Science.gov (United States)

... The lateral cross spectral density measurements are normalized on the autospectrum. Frequency is normalized on r3 , and we take Uc _" 0.7 U0 . ...

1973-12-01

258

Upper bound for a three-photon excitation cross section in atomic argon in the ultraviolet regime  

International Nuclear Information System (INIS)

A scheme of evaluating a generalized three-photon excitation cross section #sigma#/sub (3)/ in neutral atomic argon at 3144.67 A is outlined. Three photons at this wavelength can excite the neutral argon atoms from the ground 3p"6 "1S_0 state to the 3p"54s'[1/2]_1"0 state. The fourth photon will ionize the argon atoms. Assuming linear polarization of the incident laser radiation, contributions from several channels in various energy-level schemes are summed in the evaluation of the transition probability. For a laser linewidth of #DELTA##lambda#/sub L/ = 1 A, our maximum numerical value of the computed result for the three-photon excitation cross section is #sigma#/sub (3)/ = 1.414 x 10/sup -80/ cm"6 s"2. .AE.

8800-01-01

259

Unraveling mechanisms of homeostatic synaptic plasticity  

UK PubMed Central (United Kingdom)

SUMMARYHomeostatic synaptic plasticity is a negative feedback mechanism neurons use to offset excessive excitation or inhibition by adjusting their synaptic strengths. Recent...Full Text Available

2010-05-13

260

Tunable Gas Lasers Utilizing Ground State Dissociation  

Science.gov (United States)

... the effective lifetime of the excited states against spontaneous radiation is only a fe- times the natural lifetime and collisional destruction by ...

1972-09-15

261

Spitzer Mid-infrared Study of Compact HII Regions in the Magellanic Clouds  

CERN Document Server

We present a study of the mid-infrared properties and dust content of a sample of 27 HII ``blobs'', a rare class of compact HII regions in the Magellanic Clouds. A unique feature of this sample is that even though these HII regions are of high and low excitation they have nearly the same physical sizes ~1.5-3 pc. We base our analysis on archival 3-8 microns infrared imagery obtained with the Infrared Array Camera (IRAC) on board the Spitzer Space Telescope. We find that despite their youth, sub-solar metallicity and varied degrees of excitation, the mid-infrared colors of these regions are similar to those of typical HII regions. Higher excitation ``blobs'' (HEBs) display stronger 8 micron emission and redder colors than their low-excitation counterparts (LEBs).

2008-01-01

262

Radionuclide X-ray fluorescence analysis. 2: Detection of the X-ray fluorescence radiation excited by radionuclide radiation  

Science.gov (United States)

This investigation describes the technique for the detection of the X-ray fluorescent radiation

1972-01-01

263

RXTE GOF: News Archive 2004 - HEASARC - NASA  

Science.gov (United States)

May 18, 2007 ... This exciting new development in neutron star evolution was presented at the Winter 2004 AAS Meeting in Atlanta, Georgia. ...

267

Onclas U9800 - NASA Technical Report Server (NTRS)  

Science.gov (United States)

the probability of its spontaneous radiation de-excitation increases. ... consider spontaneous radiation transitions. We will examine the ...

268

On-line nuclear orientation  

Energy Technology Data Exchange (ETDEWEB)

This report discusses: shape coexistence in {sup 184}Pt; nuclear structure of {sup 187}Ir; g-factors of excited states; OLNO-2; and refrigerator development.

1992-01-01

269

On-line nuclear orientation  

International Nuclear Information System (INIS)

This report discusses: shape coexistence in "1"8"4Pt; nuclear structure of "1"8"7Ir; g-factors of excited states; OLNO-2; and refrigerator development.

271

NASA Technical Reports Server - Radionuclide X-ray fluorescence ...  

Science.gov (United States)

Aug 1, 1972 ... The principles of radionuclide excitation of X-ray fluorescence radiation and its application in analytic chemistry are discussed.

272

Microwave excitation of a CO/sub 2/ laser. Master's thesis  

Energy Technology Data Exchange (ETDEWEB)

A flowing carbon dioxide laser was operated at low pressures up to 4 torr. Excitation of the laser was provided using various combinations of direct current (DC), pulsed microwave, and continuous wave (CW) microwave excitation. The microwaves were in the 2.45 GHz band and were coupled into the gas using a slow-wave interdigital transmission line. Laser output of 25 milliwatts (mw) was achieved using a DC discharge only. A combination of a DC discharge and pulsed microwaves doubled the output and resulted in some modulation. Changing the laser gas mixture and pulsed microwave field characteristics allowed some flexibility in the modulation. Lasing was not achieved with excitation from the CW microwaves alone due to the formation of localized discharges. Using pulsed microwaves to sustain the discharge and CW microwaves to pump the laser, a quasi-CW output of 55 mw was achieved.

1983-12-01

273

Levels in "9"7Tc, "9"9Tc, "1"0"1Tc and "1"0"1Ru  

International Nuclear Information System (INIS)

... Thesis (Ph.D.). coincidence spectrometry excited states gamma spectra internal

275

High resolution (p,p') reactions on "8"7Sr and "8"8Sr  

International Nuclear Information System (INIS)

... levels excited states mev range 10-100 proton reactions proton spectra protons

276

Gamma-spectroscopy of "6"4Mn_3_9 and "6"6Mn_4_1 decays  

International Nuclear Information System (INIS)

... v. 33(4). beta-minus decay de-excitation delayed gamma radiation iron 64

277

Excited states of "1"8"7 Ir and "1"8"9Ir  

International Nuclear Information System (INIS)

... ground states iridium 187 iridium 189 beta decay radioisotopes days living

1974-08-01

278

Excited states in electronic structure calculations  

Energy Technology Data Exchange (ETDEWEB)

A first-principles quasiparticle approach to the electronic excitation energies in crystals and at surfaces is described. The quasiparticle energies are calculated within the GW approximation for comparison with photoemission and other spectroscopic experiments. Applications of the method to bulk semiconductors and the Si(111)2[times]l, Ge(111)2[times]l. and H/Si(III) surfaces are presented. In both cases, significant self-energy corrections arising from many-electron effects to the excitation energies are found. Using atomic positions from total energy minimization, the calculated excitation energies explain quantitatively the experimental spectra. This approach thus provides an ab initio means for analyzing and predicting results from spectroscopic probes.

1992-07-01

280

Excitation of global Alfven Eigenmodes by RF heating in JET  

Energy Technology Data Exchange (ETDEWEB)

The alpha-particle confinement of future D-T experiments at JET can be severely degraded by Global Alfven Eigenmodes (AE). Scenarios for the excitation of Alfven Eigenmodes in usual (e.g. D-D) plasmas are proposed, which provide a MHD diagnostic and allow the study of the transport of super-Alfvenic ions. Active studies with separate control of TAE amplitude and energetic particle destabilization, measuring the plasma response, give more information than passive studies, in particular concerning the damping mechanisms. The TAE excitation can be achieved by means of the saddle coil and the ICRH antenna. The experimental method is introduced together with a theoretical model for RF excitation. (authors). 6 refs., 3 figs.

1994-07-01

281

Electron-induced luminescence and x-ray spectrometer development  

Science.gov (United States)

Jan 22, 2011 ... dc.description.abstract, The progress in the development of a surface analysis tool based on the excitation of characteristic luminescence ...

282

Dissociative electron attachment to rovibrationally excited molecules. Annual technical report no. 1, 1 August 1984-30 September 1985  

Energy Technology Data Exchange (ETDEWEB)

The aim of this project is to investigate the dependence of the cross sections for dissociative electron attachment to a molecule on the initial rovibrational state of the molecule. An enhancement of the cross section results in the enhancement of the rate of production of negative ion beams. Preliminary investigations reveal that for lithium dimers, Li/sub 2/, the peak attachment cross sections can increase by almost an order of magnitude if the molecule is initially vibrationally excited to the v = 1 level. Excitation to higher vibrational levels would result in further enhancement of the attachment rates. As part of present investigations, the cross sections for vibrational excitation of various molecules, using both resonant and nonresonant mechanisms is calculated.

1985-09-30

283

Are transition nuclei "1"8"9Ir and "1"8"7Ir triaxial  

International Nuclear Information System (INIS)

... band theory excited states iridium 187 iridium 189 beta decay radioisotopes

1975-06-30

284

Absolute cross sections for near-threshold electron-impact excitation of the 3s"2"1S#->#3s3p"1P and 3s"2"1S#->#3s3p"3P transitions in Si"2"+  

International Nuclear Information System (INIS)

Absolute total cross sections for electron-impact excitation of the 3s"2"1S#->#3s3p"3P and 3s"2"1S#->#3s3p"1P transitions in Si"2"+ were measured using the merged electron-ion beams energy-loss technique. The results are compared to R-matrix close-coupling theory, which predicts a strong resonance enhancement of the cross section near the threshold for excitation of the "3P state and this is confirmed by the experiments. The observed disagreement between theory and experiment for the dipole excitation is suggested to be due to resonance interference. copyright 1997 The American Physical Society.

285

A Magnetic Suspension and Excitation System for Spin Vibration ...  

Science.gov (United States)

High Cycle Fatigue Initiative Workshop -Active Vibration. Control/Engine. Health Monitoring Session December 10,. 1996. The presentation was titled "Active ...

286

Is the 4.742 MeV state in "8"8Sr the 1"- two-phonon state?  

International Nuclear Information System (INIS)

A nuclear resonance fluorescence experiment on "8"8Sr has been performed with bremsstrahlung of 6.7 MeV endpoint energy. The #gamma#-ray linear polarisation has been measured with a EUROBALL CLUSTER detector used as a Compton polarimeter. The results indicate positive parity for the J=1 state at 4.742 MeV in "8"8Sr, in contrast to the previous interpretation as a 1"- two-phonon (2"+_1 x 3"-_1) state and in conflict with the predictions of the quasiparticle-phonon model. On the basis of such calculations the 1"+ state at 3.486 MeV may be considered as the 1"+_1 one-phonon state and the very strong 1"+_1#->#0"+_1 deexcitation as proton spin-flip 2p_1_/_2#->#2p_3_/_2 transition. (orig.)

2000-01-01

287

Exploring the potential energy surface for proton transfer in acetylacetone  

Energy Technology Data Exchange (ETDEWEB)

The portion of the potential energy surface (PES) of acetylacetone relevant for the intramolecular proton transfer reaction is studied using ab initio and DFT methods. The best estimate of the barrier governing proton transfer was found to be 3.4 kcal mol{sup -1} at the MP4(FC)/6-311 + G(2d,2p)//MP2(FC)/6-311 + G(2d,2p) level of theory. Six stationary points on the PES were characterized as well as the reaction paths connecting these points. Special attention paid to the pathway of intramolecular proton transfer reveals that the internal rotation of the methyl group adjacent to the carbonyl group and the proton transfer reaction are consecutive processes.

2004-11-15

288

Cholera toxin can catalyze ADP-ribosylation of cytoskeletal proteins  

International Nuclear Information System (INIS)

Cholera toxin catalyzes transfer of radiolabel from ["3"2P]NAD"+ to several peptides in particulate preparations of human foreskin fibroblasts. Resolution of these peptides by two-dimensional gel electrophoresis allowed identification of two peptides of M/sub r/ = 42,000 and 52,000 as peptide subunits of a regulatory component of adenylate cyclase. The radiolabeling of another group of peptides (M/sub r/ = 50,000 to 65,000) suggested that cholera toxin could catalyze ADP-ribosylation of cytoskeletal proteins. This suggestion was confirmed by showing that incubation with cholera toxin and ["3"2P]NAD"+ caused radiolabeling of purified microtubule and intermediate filament proteins.

1981-01-01

289

Wireless Sensor Network based Future of Telecom Applications  

CERN Document Server

A system and method for enabling human beings to communicate by way of their monitored brain activity. The brain activity of an individual is monitored and transmitted to a remote location (e.g. by satellite). At the remote location, the monitored brain activity is compared with pre-recorded normalized brain activity curves, waveforms, or patterns to determine if a match or substantial match is found. If such a match is found, then the computer at the remote location determines that the individual was attempting to communicate the word, phrase, or thought corresponding to the matched stored normalized signal.

2010-01-01

290

Wind energy mapping of coastal zones by synthetic aperture radar (SAR) for siting potential windmill locations  

Energy Technology Data Exchange (ETDEWEB)

The authors propose using synthetic aperture radar(SAR) for wind energy mapping of coastal zones. The SAR equipment is located on the European Space Agency ERS-1 and 2 and the RADARSAT satellites. Examples of wind energy maps and evaluations of their applications are given for the Norwegian west coast.

2000-07-01

291

Vehicle tracking systems  

Energy Technology Data Exchange (ETDEWEB)

Several systems have been developed to accomplish vehicle location. The systems consist of three types: Dead Reckoning, Satellite, and LORAN C. If the information is to be sent back to a central location, some type of radiocommunication system is needed. One can use the existing voice radio or add a radio system just for transmitting the data.

1987-01-01

292

Third SEI Technical Interchange: Proceedings. [Space Exploration Initiative  

Science.gov (United States)

Given here are the proceedings of the 3rd Space Exploration Initiative (SEI) Technical Interchange. Topics covered include the First Lunar Outpost (FLO), the Lunar Resource Mapper, lunar rovers, lunar habitat concepts, lunar shelter construction analysis, thermoelectric nuclear power systems for SEI, cryogenic storage, a space network for lunar communications, the moon as a solar power satellite, and off-the-shelf avionics for future SEI missions.

1992-01-01

293

The issues in electronics hardening  

International Nuclear Information System (INIS)

This paper addresses the background and the continuously evolving topics of hardening and electronic components. Typical radiation environments from 1960 are described. Examples of a civilian satellite and of future particle physics colliders help illustrate hardening problems. Effects in components, limits of shielding, and three methods of providing components are described. The authors conclude by focusing on both future trends of radiation environments and anticipated progress in electronics. (authors). 10 refs., 9 figs., 4 tabs.

294

The PAMELA space mission  

Energy Technology Data Exchange (ETDEWEB)

The PAMELA (a Payload for Antimatter-Matter Exploration and Light-nuclei Astrophysics) space mission has been launched on-board the Resurs-DK1 satellite on June 15{sup th} 2006 from the Baikonur cosmodrome, in Kazakhstan. PAMELA is a particle spectrometer designed to study charged particles in the cosmic radiation with special focus on the investigation of the nature of dark matter, by mean of the measure of the cosmic-ray antiproton and positron spectra over the largest energy range ever achieved.

2009-03-15

295

Soviet military strategy in space  

Energy Technology Data Exchange (ETDEWEB)

This book examines the Soviet military space effort from its infancy in the 1950s to the spy craft and anti-satellite systems of today. It describes in detail the Soviet equivalents of the U.S. Star Wars program and explains technical and political issues in laymen's terms. A full text of major arms control agreements completes the volume.

1987-01-01

296

Solar effects on communications  

International Nuclear Information System (INIS)

This paper focuses on potential effects of solar phenomena on communication systems used by the electric utility industry. It begins with a discussion of solar phenomena fundamentals and discussion of the interaction between solar emissions and the earth's ionosphere and magnetosphere. It continues with a discussion of the resulting impacts on communication systems including radio, satellite, wireline, fiber optic, and powerline systems and concludes with a discussion of mitigation techniques and a call for observers to report suspected solar impact experiencexperiences.

297

Satellite power systems (SPS). LSST systems and integration task for SPS flight test article. Final report  

Energy Technology Data Exchange (ETDEWEB)

This research activity emphasizes the systems definition and resulting structural requirements for the primary structure of two potential SPS large space structure test articles. These test articles represent potential steps in the SPS research and technology development.

1981-02-01

298

Report on the special program 78 satellite geodesy of the technical university of Munich  

Energy Technology Data Exchange (ETDEWEB)

Various topics include: (1) direction finding, (2) range finding, (3) Doppler measurements, (4) construction of a receiver for radio interferometry, (5) mobile laser range finding system, (6) figure-and field parameter determination/geopotential, (7) dynamics of the Earth-Moon system, and (8) kinematics of geodetic point fields.

1981-01-01

299

Repetitive satellite-like sequences are present within or upstream from 3 avian protein-coding genes.  

UK PubMed Central (United Kingdom)

Peculiar DNA sequences made up by the tandem repetition of a 5 bp unit have been identified within or upstream from three avian protein-coding genes. One sequence is located within an intron of the...Full Text Available

1983-03-11

300

Proton transport, an examination of model and experimental data for space environment protons; Blindage aux protons, comparaison entre modele et donnees experimentales pour les protons du rayonnement spatial  

Energy Technology Data Exchange (ETDEWEB)

We will examine modeling data for various orbits using modeling software and compare this with actual satellite flight result. In particular, we will discuss the contributions of trapped protons to total dose and the effectiveness of shielding.

1999-07-01

301

Particulate air pollution and chronic ischemic heart disease in the eastern United States: a county level ecological study using satellite aerosol data  

UK PubMed Central (United Kingdom)

BackgroundThere are several known factors that cause ischemic heart disease. However, the part played by air pollution still remains something of a mystery. Recent attention has...Full Text Available

302

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

Science.gov (United States)

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

1987-01-01

303

Neutrons in Biology. A satellite meeting of the IUPAB/EBSA biophysics congress  

Energy Technology Data Exchange (ETDEWEB)

This meeting focussed on the study of the structure and dynamics of biological molecules, with particular emphasis on neutron and complementary methods as well as related enabling technologies. The program covered biological problems that are being addressed by neutron scattering and those where there is the potential to do so in the future. This document provides the abstracts of the different presentations. (A.L.B.)

2005-07-01

304

Heat pipes and two-phase loops with capillary pumping; Caloducs et boucles diphasiques a pompage capillaire  

Energy Technology Data Exchange (ETDEWEB)

This workshop on heat pipes and two-phase capillary pumping loops was organized by the French society of thermal engineers. The 11 papers presented during this workshop deal with the study of thermal performances of heat pipes and on their applications in power electronics (cooling of components), and their use in satellites, aircrafts and trains. (J.S.)

1996-12-31

305

Estimating Regional Spatial and Temporal Variability of PM2.5 Concentrations Using Satellite Data, Meteorology, and Land Use Information  

UK PubMed Central (United Kingdom)

BackgroundStudies of chronic health effects due to exposures to particulate matter with aerodynamic diameters ≤ 2.5 μm (PM2.5) are often limited by sparse...Full Text Available

2009-06-01

306

Environmental assessment of coal waste mounds in Japan using remote sensing techniques  

Energy Technology Data Exchange (ETDEWEB)

Focuses on the application of remote sensing techniques to the study of coal waste mounds. The situation at the coal waste mounds in Fukuoka, Japan is cited. Guidelines on film parameters, photographic keys and tasks required to inventory, monitor and manage coal waste mounds in Japan are addressed. Application of photogrammetry, remote sensing, aerial photography and satellite imagery techniques in monitoring spoil banks is reviewed. Applicability of the techniques is discussed. 24 refs.

1993-01-01

307

Detecting mining subsidence from space  

Energy Technology Data Exchange (ETDEWEB)

The aim is to provide accurate data on elevation change due to mining activity, via the application of interferometry with ERS SAR data. Ultimately, these elevation changes can then be fed into subsidence models. Interferometry results are presented showing initial evidence of subsidence occurring within the 35 day repeat orbit period of the ERS satellites. The result of extending the monitoring period beyond 35 days is also shown.

1999-04-01

308

BUBL LINK: Oceanographic data  

Wastenet

...6 Resource type: reference data Global Change Master Directory An extensive source of information about satellite and in situ Earth science data, with broad coverage of the atmosphere, hydrosphere, oceans, solid earth, and biosphere. Author: NASA Subjects: climatology, global change, oceanographic data DeweyClass: 551.6 Resource type: documents, news International ...

309

Assimilation of Remote Sensing Data into Shelf Sea Hydrodynamic Models  

Environmental Research Database

DescriptionRemote sensing of the sea surface from satellites in near-polar orbits has contributed greatly to our understanding of the links between physical and biological processes in marine systems. However most of this progress has been made in open oceanic waters or major upwelling areas, and many unresolved problems are encountered in coastal regions and shelf seas. In these optically complex waters, quantitative remote sensing requires a more sophisticated interpretation strategy than that implemente [continued...

310

Analysis and Assessment of Land Use Change in Alexandria, Egypt Using Satellite Images, GIS, and Modelling Techniques  

International Nuclear Information System (INIS)

Alexandria is the second largest urban governorate in Egypt and has seen significant urban growth in its modern and contemporary history. This study investigates the urban growth phenomenon in Alexandria, Egypt, using the integration of remote sensing and GIS. The urban physical expansion and change were detected using Landsat satellite images. The satellite images of years 1984 and 1993 were first geo referenced, achieving a very small RMSE that provided high accuracy data for satellite image analysis. Then, the images were classified using a tailored classification scheme with accuracy of 93.82% and 95.27% for 1984 and 1993 images respectively. This high accuracy enabled detecting land use/land cover changes with high confidence using a post-classification comparison method. One of the most important findings here is the loss of cultivated land in favour of urban expansion. If the current loss rates continued, 75% of ...

311

A magneto-electric quantum wheel  

CERN Document Server

Here we show that self-propulsion in quantum vacuum may be achieved by rotating or aggregating magneto-electric nano-particles. The back-action follows from changes in momentum of electro-magnetic zero-point fluctuations, generated in magneto-electric materials. This effect may provide new tools for investigation of the quantum nature of our world. It might also serve in the future as a "quantum wheel" to correct satellite orientation in space.

2009-01-01

312

On the Resolving Power of a Single Exact-Repeat Altimetric Satellite or a Coordinated Constellation of Satellites  

Science.gov (United States)

It is proved that the mid-point grid, which is composed of samples obtained at ground track locations midway between crossover points (thus a subset of the full sampling), has the same resolving power as the full set; i.e., they resolve the same three-dimensional spectral space. The resolving power of the mid-point grid as derived previously by Tai (1995, 1998) is characterized by the Nyquist frequency ? c=? /T (where T is the repeat period of the exact-repeat satellite), and by (in local Cartesian coordinates) the zonal and meridional Nyquist wavenumber kc=2? /X and lc=2? /Y respectively (where X and Y are the east-west and north-south separation between adjacent parallel ground tracks). Here we re-derive this result in simplified terms. First, it is shown through the sampling theorem as demonstrated previously by Tai (1999) that even though samples of the real mid-point grid are not taken simultaneously, they resolve the same frequency range as that of a ...

2001-12-01

313

Working group report on electron-impact processes: Recommended database for electron impact excitation and ionization  

International Nuclear Information System (INIS)

The cross section database for electron impact excitation and electron impact ionization for hydrogen beam kinetic energies greater than 100 eV was considered, giving for each particular process a reference to a recommended publication of cross sections, as well as the accuracy or estimated accuracy. The work is motivated by the application of neutral beam injection in magnetic confinement devices, such as large tokamaks. 9 refs, 2 figs.

1989-07-01

314

Transient enhanced diffusion of oxygen in Fe mediated by large electronic excitation  

International Nuclear Information System (INIS)

Contrary to the electronic excitation induced phenomena of desorption and sputtering, we observed incorporation of oxygen in a thin Fe film during its irradiation with swift heavy ions. It is observed that the adsorbed oxygen diffuses in to the Fe film. The incorporation of oxygen and its diffusion in the bulk of the film is a manifestation of extremely large electronic energy deposition by the incident ions. It is shown that the experimentally observed high diffusivity of oxygen in Fe during irradiation is due to the existence of transient melt phase of Fe.

2003-10-15

315

Topological excitations and second order transitions in 3D O(N) models  

Energy Technology Data Exchange (ETDEWEB)

I discuss several examples of critical phenomena in O(N) models where topological excitations play an important role at criticality. I focus particular attention on the O(2) model in 3D, where recent measurements of the vortex string length distribution in equilibrium suggest the existence of a quantitative picture of the critical behavior in terms of defects. The compatibility of this perspective with renormalization group predictions is examined.

2001-01-01

316

Theory of isomer ratios of shape isomers in heavy ion induced reactions  

Science.gov (United States)

A method for the calculation of excitation functions and isomer ratios, for shape isomers, in heavy ion induced reactions is proposed. The calculated values of excitation functions and isomer ratios agree very well with the experimental values for the reaction /sup 238/U(/sup 11/B, alpha 3n)/sup 242/Am. (auth)

1973-11-12

317

One-photon two-electron processes in helium close to the double ionization threshold; Diexcitation electronique de l'helium par un photon au voisinage du seuil de double ionisation  

Energy Technology Data Exchange (ETDEWEB)

This work presents a study of the {sup 1}P{sup 0} excited states of He that can be reached by absorption of a single photon carrying an energy close to the double ionization threshold (DIT) (79 eV). Above the DIT, these states are the double continuum states; below, they are the double excited states. These two types of states are tightly coupled to the single continuum states with or without excitation of the residual ion He{sup +}, owing to their degeneracy in energy. In a one-photon process, these states can only be formed owing to the electronic correlations in the system which must be well described to obtain quantitative good results. Our study is a part of the work which aims at a united description of all these doubly excited, ionized-excited, and double continuum states. We use the Hyperspherical R-Matrix with Semiclassical Outgoing Waves (HRM-SOW) method, initially ...

2007-04-15

318

Muon induced fission in high threshold nuclei  

International Nuclear Information System (INIS)

Muon captures by nucleon pairs via meson-exchange currents produce a high energy excitation tail in heavy nuclei. The muon induced fission by these excitations is calculated in several subactinide nuclei with high threshold fission barriers. The probability for delayed fission ranges from 4 x 10"-"5 to 4 x 10"-"3 for the isotopes considered. (orig.).

319

Magnetic excitations in the antiferromagnetic Kondo compound CePd_2Si_2  

International Nuclear Information System (INIS)

The magnetic excitations of the Kondo compound CePd_2Si_2 below its Neel temperature (T_N = 10 K) have been studied by inelastic neutron scattering. At T = 1.6 K the data are best represented by two dispersive inelastic modes. Their linewidth (#propor to# 0.5 meV) indicates substantial broadening, which is ascribed to Kondo-type local fluctuations. (orig.).

320

Intrinsic and extrinsic crossluminescence in ionic crystals  

Energy Technology Data Exchange (ETDEWEB)

Intrinsic crossluminescence (CRL) of CsBr, CsCl, and of BaF{sub 2} was investigated with electron-beam and synchrotron radiation excitation. From the CRL spectra, the excitation spectra and the reflectivity, energy level schemes were deduced. Extrinsic CRL was observed changing either the initial (CsCl:Br{sup -}) or the final (RbCl:Cs{sup +}; KCl:Cs{sup +}) state of CRL by doping. (author).

1991-01-01

321

Intrinsic and extrinsic crossluminescence in ionic crystals  

International Nuclear Information System (INIS)

Intrinsic crossluminescence (CRL) of CsBr, CsCl, and of BaF_2 was investigated with electron-beam and synchrotron radiation excitation. From the CRL spectra, the excitation spectra and the reflectivity, energy level schemes were deduced. Extrinsic CRL was observed changing either the initial (CsCl:Br"-) or the final (RbCl:Cs"+; KCl:Cs"+) state of CRL by doping. (author).

1990-09-03

322

Electromagnetic effects in relativistic electron beam plasma interactions  

Energy Technology Data Exchange (ETDEWEB)

Electromagnetic effects excited by intense relativistic electron beams in plasmas are investigated using a two-dimensional particle code. The simulations with dense beams show large magnetic fields excited by the Weibel instability as well as sizeable electromagnetic radiation over a significant range of frequencies. The possible relevance of beam plasma instabilities to the laser acceleration of particles is briefly discussed. 6 refs., 4 figs.

1985-02-13

323

EXCITATION OF ISOBARIC ANALOG STATES IN $sup 89$Y AND $sup 90$Zr  

Science.gov (United States)

The excitation of compound-nucleus resonances in Y/sup 89/ and Zr/sup 90/ by proton bombardment at 4 to 5.5 Mev of Sr/sup 88/ and Y/sup 89/, respectively, is reported. Shell-model corfigurations were used to interpret the results. (R.E.U.)

1964-02-24

324

Differences of the deformation parameter #beta# for 2"+_1 states of even-even spherical nuclei from electromagnetic excitation and proton scattering  

International Nuclear Information System (INIS)

Differences of the deformation parameters for the 2"+_1 states of even-even spherical nuclei extracted from electromagnetic excitation #beta#sup(em)_2 and from proton scattering #beta#sup(pp')_2 are discussed. It is found that the ratio #beta#sup(pp')_2/#beta#sup(em)_2 is equal to about unity and that there is a small isotope dependence for several incomplete shell nuclei. (orig.).

325

Closed smooth strings on a torus  

Energy Technology Data Exchange (ETDEWEB)

The free energy of a gas of closed strings with extrinsic curvature (smooth strings) is evaluated on a torus. This is compared with the free energy of a collection of free particles, and hence the mass spectrum of excitations of the smooth strings is deduced. It is found that above a critical value of the coupling constant of the curvature term the spectrum is free of tachyons. Furthermore, there are no massless spin-2 excitations. The absence of massless spin-2 fields is a consequence of the fact that the smooth-string theory is not modular invariant.

1988-02-15

326

Application of isotope-excitation x-ray fluorescence (XRF) analysis for aluminium production  

International Nuclear Information System (INIS)

An energy sensitive Si(Li) detector XRF analyzer built by ATOMKI, Hungary, has been applied for various analytical purposes in alumina production at the Almasfuezitoe Alumina Company, Hungary. Specifically, the CaO content in red mud was determined by the new XRF technique using isotope excitation sources. The analysis of other components is under way. (R.P.).

328

Alpha particle induced excitation functions with "1"4"1Pr  

International Nuclear Information System (INIS)

In the present work the excitation functions for the reactions "1"4"1Pr(#alpha#,n)"1"4"4Pm and "1"4"1Pr(#alpha#,2n)"1"4"3Pm have been measured experimentally below 50 MeV #alpha#-particle

1998-12-01

329

(Photoexcited charge pair escape and recombination)  

Science.gov (United States)

Progress in four research areas on this project are summarized under the following topics: (1) Geminate charge pair recombination in hexane; (2) Fast current measurements resulting from excitation of charge transfer (CT) states; (3) Measurement of the dipole moment of excited states by DC conductivity; and (4) Charge separation at macroscopic interfaces between electron donor and acceptor solids. In a final section, personnel who have contributed to the project during the past budget period are described.

1990-01-01

330

Two and 8-azido photoaffinity probes. 2. Studies on the binding process of 2-5A synthetase by photosensitive ATP analogues  

International Nuclear Information System (INIS)

The photoaffinity probes [#gamma#-"3"2P]2-azidoATP (2-N_3ATP) and [#alpha#-"3"2P]8-azido-ATP (8-N_3ATP) were used to investigate the binding of ATP to highly purified 2-5A synthetase. 2-N_3APT and 8-N_3ATP are substrates for 2-5A synthetase. In this study the authors show that 2- and 8-N_3ATP are competitive inhibitors of the enzymatic conversion of ATP to 2-5A. Ultraviolet irradiation results in the photoinsertion of 2-N_3ATP and 8-N_3ATP into the enzyme. The covalent photoinsertion of [#alpha#-"3"2P]8-N_3ATP into the 2-5A synthetase is proportional to the inactivation of the enzyme as UV irradiation is increased. Photolabeling of 2-5A synthetase is saturated at 1.5 mM 2-N_3ATP and 2.0 mM 8-N_3ATP. Computer analysis of the curvilinear Scatchard plots of the 2-5A synthetase suggest the presence of high-affinity and low-affinity binding sites that may correspond ...

331

Selective control of amino acid metabolism by the GCN2 eIF2 kinase pathway in Saccharomyces cerevisiae  

UK PubMed Central (United Kingdom)

BackgroundWhen eukaryotic cells are deprived of amino acids, uncharged tRNAs accumulate and activate the conserved GCN2 protein kinase. Activated Gcn2p up-regulates the general amino...Full Text Available

332

Radiochemistry of lead-203 for radiolabelling antibody conjugates  

International Nuclear Information System (INIS)

Lead-203 [52.1 h, 279 (80.1%) KeV] has been recognized as a potentially useful tracer for tumor specific radiopharmaceuticals due to its favorable nuclear and chemical properties. This paper reports the cyclotron production of lead-203 and the labelling of monoclonal antibody B72.3, conjugated with 2-(p-isothiocyanatobenzyl)DOTA, with lead-203 in 30% yield. In vivo biodistribution and stability studies in mice are being conducted.

1990-06-24

333

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

334

Comparative transcriptional pathway bioinformatic analysis of dietary restriction, Sir2, p53 and resveratrol life span extension in Drosophila  

UK PubMed Central (United Kingdom)

A multiple comparison approach using whole genome transcriptional arrays was used to identify genes and pathways involved in calorie restriction/dietary restriction (DR) life span extension in Drosophila....Full Text Available

2011-03-15

335

Reduction of nitrogen oxides (NO{sub x}) production in a liquid fuel-oil diffusion flame by acoustic excitation; Reduction de la production des oxydes d`azote (NO{sub x}) dans une flamme de diffusion a fioul liquide par excitation acoustique  

Energy Technology Data Exchange (ETDEWEB)

The control of nitrogen oxides (NO{sub x}) emissions will become a major challenge in the forthcoming years, in the domain of automotive industry or industrial burners. Pulsed combustion offers an imaginative solution which does not affect the combustion efficiency. In this paper, the efficiency of this method is demonstrated using the burner of a 20 kW domestic boiler. The actuator is simply installed on the air intake. Two types of actuators have been tested successfully: a loudspeaker and a rotative valve. Both can produce 100 to 1000 Hz frequencies and can lead to a reduction of 20% of NO{sub x} emissions. The feasibility of the concept is also demonstrated on a 840 kW liquid fuel-oil burner. The mechanisms involved during an excitation are explained using the CH{sup *} radical imaging. Results show an important reorganization of the flow and of the flame structure. During each excitation cycle, an annular swirl occurs at the leading edge ...

1996-12-31

336

On the temperature dependence of the magnetic excitations  

International Nuclear Information System (INIS)

We compare experimental data for temperature dependence of the magnetic order parameter and the magnetic excitations (spin waves) in materials with a quenched orbital moment and a well-defined spin quantum number. It is observed that the thermal decrease of the two quantities proceeds according to the same analytical function of the type y(T)=1-cT"#epsilon# with an identical exponent #epsilon#. This power function applies not only asymptotically for T->0 but holds over a wide temperature range. The exponent #epsilon# is universal, i.e. independent of spin order type and lattice symmetry and depends only on the dimensionality of the relevant interactions and on whether the spin quantum number is integer or half-integer. The different T"#epsilon# functions are identified as representations of stable universality classes. The fact that order parameter and magnetic excitations follow the same T"#epsilon# function shows that the two quantities ...

2005-07-15

337

Luminescence properties of europium and terbium activated yttrium niobium/tantalate phosphors under VUV-UV excitation  

International Nuclear Information System (INIS)

Various compositions of Y(Ta,Nb)O4:Eu3+,Tb3+ with different Nb and activator concentrations have been investigated under UV and VUV excitation. Some compounds with very strong emission under VUV excitation were found. Such phosphors could be proposed as very good emissive materials for Displays and Lightings. The growing interest in luminescence spectroscopy of rare earth ions in the vacuum ultraviolet (VUV) and the visible (VIS) spectral range is due to industrial demands for new applications. YTaO4 and YNbO4 phosphors are a perspective class of efficient materials that are generally used in X-ray intensifying screens. These phosphors exhibit satisfying luminescence whenever excited by UV light, cathode radiation or X ray. However, to our knowledge, no work has been published on the VUV-excited luminescence for Eu3+ and Tb3+ double activated yttrium niobate and yttrium tantalate based phosphors. In ...

338

Inelastic-energy-loss measurements of multiple N- and M-shell excitations in 0.3- to 1.2-MeV Xe"+-Xe collisions  

International Nuclear Information System (INIS)

The inelastic energy losses for single collisions of Xe"+ ions with Xe targets have been measured for incident ion energies from 0.3 to 1.2 MeV and for scattering angles from 3"0 to 20"0. The energy losses were found to range from 1 to 11 keV with distinct steps at distances of closest approach of 0.22 and 0.12 A. By comparing these data with earlier ionization data by the same authors these steps are shown to be caused by M-shell excitation. Other excitations observed in the ionization data may be attributed to N-shell excitation. The distances of closest approach at which these excitations occur agree well with calculations by Eichler and Wille and co-workers, giving further evidence of the usefulness of Fano and Lichten's one-electron molecular model and these calculations.

339

Extended Gas in Seyfert Galaxies Near Infrared Observations of NGC 2110 and Circinus  

CERN Document Server

We present results of near--IR long-slit spectroscopy in the J and K bands of the Seyfert 2 galaxies NGC 2110 and Circinus, investigating the gaseous distribution, excitation, reddening and kinematics. In NGC 2110, the emission line ratio [FeII]/Pa beta increases towards the nucleus (to ~ 7). The nuclear [Fe II]1.257 (microns) and Pa beta lines are broader (FWHM ~ 500 km/s) than the H2 (2.121) line (FWHM ~ 300 km/s). Both these results suggest that shocks, driven by the radio jet, are an important source of excitation of [Fe II]. The H2 excitation appears to be dominated by X-rays from the nucleus. In Circinus, both [FeII]/Pa beta and H2/Br gamma decrease from ~ 2 at 4 arcsec from the nucleus to nuclear values of ~ 0.6 and ~ 1, respectively, suggesting that the starburst dominates the nuclear excitation, while the AGN dominates the excitation further out (r > 2 arcsec). For both ...

1998-01-01

340

Decay of "1"7"7T_a composite nucleus. Comparison of excitation functions for the reaction residues occurring in "1"2C + "1"6"5H_0 and "1"4N + "1"6"3D_y reactions  

International Nuclear Information System (INIS)

The experimental has been performed with a view to studying complete and incomplete fusion in "1"4N + "1"6"3D_y system below 7 MeV/nucleon. The excitation functions for several reactions have been measured using the activation technique and compared with the theoretical predictions based on statistical models. The codes ALICE-91 and CASCADE used earlier for the analysis of excitation functions in case of "1"2C + "1"6"5H_0 system have been used here also with the same set of input parameters. It has been observed that the theoretical calculations do not match with the experimental excitation functions well but the overall shape of the excitation function is reproduced satisfactorily. The composite nucleus ("1"7"7T_a) formed in this ("1"4N + "1"6"3D_y) case is the same as the one formed in "1"2C + "1"6"5H_0 system studied earlier. Measured excitation functions for the same decay ...

2002-10-01

341

Three-dimensional particle simulation of plasma instabilities and collisionless reconnection in a current sheet  

Energy Technology Data Exchange (ETDEWEB)

Generation of anomalous resistivity and dynamical development of collisionless reconnection in the vicinity of a magnetically neutral sheet are investigated by means of a three-dimensional particle simulation. For no external driving source, two different types of plasma instabilities are excited in the current layer. The lower hybrid drift instability (LHDI) is observed to grow in the periphery of current layer in an early period, while a drift kink instability (DKI) is triggered at the neutral sheet in a late period as a result of the nonlinear deformation of the current sheet by the LHDI. A reconnection electric field grows at the neutral sheet in accordance with the excitation of the DKI. When an external driving field exists, the convective electric field penetrates into the current layer through the particle kinetic effect and collisionless reconnection is triggered by the convective electric field earlier than the DKI is ...

1999-06-01

342

The influence of chemically active gas on the light emission of metallic targets bombarded by positive ions  

International Nuclear Information System (INIS)

The introduction of oxygen in the vicinity of a metallic target surface, bombarded with positive argon ions of twenty kiloelectron-volts, increases the number of sputtered atoms in the excited state. This phenomenon of exaltation, very sensitive in the case of nickel and aluminium, is much less marked in the case of molybdenum. Moreover, the emission of excited particles coming from the beam's ions is not modified. A quantum-mechanical model of a kinetic emission process, which permits the interpretation of the clean metallic target's emission phenomena, seems insufficient to explain all of the results obtained in the presence of oxygen. In this last case one can therfore use a thermodynamic model in which excited metallic particles can be formed directly by chemical surface reactions of neutralization or reduction. (orig.).

343

Spontaneous excitation of an accelerated atom in a spacetime with a reflecting plane boundary  

Science.gov (United States)

We study a two-level atom in interaction with a real massless scalar quantum field in a spacetime with a reflecting boundary. The presence of the boundary modifies the quantum fluctuations of the scalar field, which in turn modifies the radiative properties of atoms. We calculate the rate of change of the mean atomic energy of the atom for both inertial motion and uniform acceleration. It is found that the modifications induced by the presence of a boundary make the spontaneous radiation rate of an excited inertial atom oscillate near the boundary and this oscillatory behavior may offer a possible opportunity for experimental tests for geometrical (boundary) effects in flat spacetime. While for accelerated atoms, the transitions from ground states to excited states are found to be possible even in a vacuum due to changes in the vacuum fluctuations induced by both the presence of the boundary and the acceleration of atoms, and this can be ...

2005-09-15

344

Relativistic distorted-wave results for nickel-like gadolinium  

Science.gov (United States)

Electron collisional data are required for population kinetics modeling and spectral predictions of highly ionized ions in high-temperature plasmas. Nickel-like ions are especially interesting for their potential use in soft X-ray laser schemes pumped by electron collisional excitation and recombination. For highly stripped ions of moderate to high Z, relativistic effects begin to play a role in the atomic-physics calculations. A relativistic multiconfigurational distored-wave model has been used for the calculation of electron excitation cross sections and rate coefficients between the 3s2 3p6 3d10 Ni-like Gd ground state and the singly excited states with an N-shell electron.

1986-08-01

345

Optical properties and up-conversion of Pr"3"+ doped CdS nanoparticles in sol-gel glasses  

International Nuclear Information System (INIS)

Silica glasses containing Pr"3"+ with and without CdS nanoparticles were prepared by sol-gel technique. The influence of CdS nanoparticles on Pr"3"+ doped glass was studied by absorption, photoluminescence and up-conversion. From the measured intensities of various absorption bands of these glasses, the Judd-Ofelt parameters ?_2, ?_4 and ?_6 have been evaluated. The radiative transition probability (A), radiative lifetime (?_R), branching ratio (?_R) and integrated emission cross-section (?_P) were calculated from excited states of "3P_1 and "3P_0 levels. The up-conversion emissions were found in the green, orange and red regions under 800 nm excitation with peaks 559, 612 and 688 nm respectively. On excitation with 370 nm also leads to similar green, orange and red regions.

2010-10-01

346

Measurements of vibrational excitation of N_2, CO, and NO by low energy proton impact  

International Nuclear Information System (INIS)

Differential scattering experiments are reported for proton impact on N_2, CO, and NO in the energy range E/sub lab/=30--80 eV. The measurements include the range of very small scattering angles around 0"0 as well as the rainbow region. The vibrationally resolved energy-loss spectra show a relatively low vibrational inelasticity for all three systems. Differential cross sections, transition probabilities, and the mean vibrational energy transfer are presented. Rotational excitation is indicated by the broadening of the energy-loss peaks which is most significant for H"+--NO. The small-angle scattering data for vibrational excitation in CO show good agreement with the impact parameter theory using the known long-range interactions for this system.

1979-07-01

347

Luminescence spectroscopy of Er3+-doped and Er3+, Yb3+-codoped LaPO4 single crystals  

International Nuclear Information System (INIS)

LaPO4 single crystals lightly doped with Er3+, and codoped with Er3+ and Yb3+ have been grown by spontaneous nucleation in a lead phosphate flux. Absorption and luminescence spectra have been measured in the visible and near-IR regions and the excited state dynamics has been studied upon pulsed laser excitation. The obtained results have allowed the evaluation of the effective emission cross-sections around 1.5 ?m, that have been found to be similar to important oxide laser crystals doped with Er3+. Efficient visible upconversion has been observed upon excitation at 980 nm in the codoped crystals. This behaviour is attributed to Yb3+-Er3+ energy transfer processes.

2009-05-01

348

Laser-Cooling of Liquid Water by the Ar-Xe Laser Radiation  

CERN Document Server

An effect of laser-cooling of water was observed for the first time with a temperature decrease dT = -2.2 K after irradiation of liquid water surface by a powerful Ar-Xe pulse laser with a pulse energy of about 1 J and wavelength L = 1.73, 2.63 and 2.65 um. The discovered effect can apparently be ascribed to the optical excitation of vibrational states of H2O molecules followed by an endothermic consolidation of chemically active excited molecules into a quasi-stable cluster-like structure. The measured time dependences of the cooling effect show that a typical life time of the new state of water amounts to hours. It has also been shown that the life time of the excited vibrational molecular states due to a radiation trapping effect can be estimated to at least hundreds of seconds.

2010-01-01

349

K/sub. beta. //K/sub. cap alpha. / X-ray intensity ratio following K-electron capture and radioisotope excitation  

Energy Technology Data Exchange (ETDEWEB)

The K/sub ..beta..//K/sub ..cap alpha../ X-ray intensity ratios are measured for Mn and Fe and for six other elements with Z lying in the range 49 less than or equal to Z less than or equal to 82 following electron capture decay and photon excitation using /sup 241/Am and /sup 57/Co sources. High-resolution Si(Li) and HpGe detector systems were used in the experiments. The dependence of K/sub ..beta..//K/sub ..cap alpha../ values on the mode of excitation in the case of Mn and Fe is attributed to chemical effects, while no such dependence is found for the high-Z elements.

1987-01-01

350

Identification of model parameters of excitation system and power system stabilizer of Mingtan{number_sign}6 via finalization field tests  

Energy Technology Data Exchange (ETDEWEB)

Experiences with the model parameter identification of the excitation system (EXS) and the power system stabilizer (PSS) for Mingtan{number_sign}6 pumped storage generation unit of Taiwan Power System are presented in this paper. The input-output data corresponding to each block of the EXS and PSS were obtained when the finalization tests of this unit were performed. The generalized least squares (GLS) approach is introduced and employed to identify the desired parameters of the noisy excitation system and PSS models. In this method, the reduction technique of biased estimates due to the non-white (correlated) identification residual is also applied to improve the accuracy of identification. The results of the parameter estimation are satisfactory. The GLS parameter identification method using the measured data at finalization tests is then suggested from the viewpoint of economy and engineering.

1995-05-01

351

High-resolution spectroscopy of Er{sup 3+} ions in 6H SiC  

Energy Technology Data Exchange (ETDEWEB)

In this work, we present results of a systematic study of optical properties of Er{sup 3+} ions in 6H SiC. The role of N-donors played in activation of photoluminescence (PL) of erbium at 1.5 {mu}m was investigated. We have confirmed that N-donors are necessary for activation of the Er PL on one hand, whereas on the other we present evidence that N-donors compete for excitation with Er centres. The high-resolution measurements of the Er{sup 3+} PL were performed aiming at determination of crystal field split levels of the {sup 4}I{sub 15/2} ground and {sup 4}I{sub 13/2} first excited multiplet of Er{sup 3+} ions. Careful analysis of temperature evolution of individual PL lines allowed proposing energy level schemes for the ground and first excited states.

2003-12-15

352

High-resolution spectroscopy of Er"3"+ ions in 6H SiC  

International Nuclear Information System (INIS)

In this work, we present results of a systematic study of optical properties of Er"3"+ ions in 6H SiC. The role of N-donors played in activation of photoluminescence (PL) of erbium at 1.5 #mu#m was investigated. We have confirmed that N-donors are necessary for activation of the Er PL on one hand, whereas on the other we present evidence that N-donors compete for excitation with Er centres. The high-resolution measurements of the Er"3"+ PL were performed aiming at determination of crystal field split levels of the "4I_1_5_/_2 ground and "4I_1_3_/_2 first excited multiplet of Er"3"+ ions. Careful analysis of temperature evolution of individual PL lines allowed proposing energy level schemes for the ground and first excited states.

2003-12-15

353

Excitation of ''M1 transitions'' in inelastic proton scattering  

Energy Technology Data Exchange (ETDEWEB)

The high selectivity of 201 MeV inelastic proton scattering at forward angles for exciting ..delta..L=0 spin flip transitions is outlined by comparison with (e,e') and 65 MeV (p,p') measurements. A summary of the results obtained on the calcium isotopes, the N=28 isotones, /sup 88/Sr and /sup 90/Zr is presented. The differences in the relative M1 strength distributions between the (p,p') and the (e,e') results are discussed. Preliminary results on /sup 208/Pb are given; the ''isoscalar'' 1/sup +/ state at 5.846 MeV is excited.

1984-03-01

354

Excitation functions and yields of the (d,p) reactions on natural molybdenum for deuteron energies less than 13 MeV  

International Nuclear Information System (INIS)

The excitation functions of the reactions "9"8Mo(d,p)"9"9Mo and "1"0"0Mo(d,p)"1"0"1Mo have been determined by irradiation of stacked foils with deuterons of energies less than 13 MeV and non-destructive determination of the absolute activity of the Mo radioisotopes by semiconductor #gamma#-ray spectrometry. From the excitation functions, the thick-target yields and the saturation production rates of "9"9Mo and "1"0"1Mo for deuteron energies of 13.0 MeV and 11.7 MeV have been calculated. Implications for the production of "9"9Mo for generators of sup(99m)Tc are discussed. (author).

355

An analytical study on excitation of nuclear-coupled thermal hydraulic instability due to seismically induced resonance in BWR  

Energy Technology Data Exchange (ETDEWEB)

A core-wide in-phase neutron flux oscillation, which took place, for example, at LaSalle-2 in the USA in 1988, is one of the nuclear-coupled thermal hydraulic instabilities in boiling water reactors (BWRs). In this study, an analysis has been performed focusing on the excitation of this type of instability in BWRs due to seismically induced resonance, within the scope of a point kinetics model. For this purpose, the TRAC-BF1 code has been modified to take into account the external acceleration in addition to gravity. As a result of this analysis, it is shown that reactivity insertion can occur accompanied by in-surge of the coolant into the core resulting from excitation. It is also shown that the amount of reactivity inserted largely depends on the degree of stability of the initial state and the amplitude of the seismic wave, whose frequency is the same as the characteristic frequency of the instability. (orig.).

1996-04-01

356

An analytical study on excitation of nuclear-coupled thermal hydraulic instability due to seismically induced resonance in BWR  

International Nuclear Information System (INIS)

A core-wide in-phase neutron flux oscillation, which took place, for example, at LaSalle-2 in the USA in 1988, is one of the nuclear-coupled thermal hydraulic instabilities in boiling water reactors (BWRs). In this study, an analysis has been performed focusing on the excitation of this type of instability in BWRs due to seismically induced resonance, within the scope of a point kinetics model. For this purpose, the TRAC-BF1 code has been modified to take into account the external acceleration in addition to gravity. As a result of this analysis, it is shown that reactivity insertion can occur accompanied by in-surge of the coolant into the core resulting from excitation. It is also shown that the amount of reactivity inserted largely depends on the degree of stability of the initial state and the amplitude of the seismic wave, whose frequency is the same as the characteristic frequency of the instability. (orig.).

1996-01-01

357

Alpha-induced reactions in iridium  

Energy Technology Data Exchange (ETDEWEB)

The excitation function of ({alpha},{ital xn}) reactions on {sup 191}Ir (abundance 37.3%) and on {sup 193}Ir (abundance 62.7%) has been measured for the 17--55 MeV alpha-particle bombarding energy range. The stacked foil activation technique and {gamma}-ray spectroscopy were used to determine the cross sections. The experimental data were compared with calculated values obtained by means of a geometry-dependent hybrid model. The initial exciton number {ital n}{sub 0}=4 with {ital n}=2, {ital p}=2, and {ital h}=0 gives the best agreements with the presently measured results. To calculate the excitation function theoretically a computer code was used. This set of excitation functions provides a data basis for probing the validity of combined equilibrium and preequilibrium reaction models in a considerable energy range.

1992-05-01

358

Using ERS-2 SAR images for routine observation of marine pollution in European coastal waters  

Energy Technology Data Exchange (ETDEWEB)

More than 660 synthetic aperture radar (SAR) images acquired over the southern Baltic Sea, the North Sea, and the Gulf of Lyon in the Mediterranean Sea by the Second European Remote Sensing Satellite (ERS-2) have been analyzed since December 1996 with respect to radar signatures of marine pollution and other phenomena causing similar signatures. First results of our analysis reveal that the seas are most polluted along the main shipping routes. SAR images acquired during descending (morning) and ascending (evening) satellite passes show different percentages of oil pollution, because most of this pollution occurs during night time and is still visible on the SAR images acquired in the morning time. Moreover, we found a higher amount of oil spills on SAR images acquired during summer (April-September) than on SAR images acquired during winter (October-March). We attribute this finding to the higher mean wind speed encountered in all three test ...

1999-09-30

359

Scattered Light from Close-in Extrasolar Planets: Prospects of Detection with the MOST Satellite  

CERN Document Server

The ultra-precise photometric space satellite MOST (Microvariability and Oscillations of STars) will provide the first opportunity to measure the albedos and scattered light curves from known short-period extrasolar planets. Due to the changing phases of an extrasolar planet as it orbits its parent star, the combined light of the planet-star system will vary on the order of tens of micromagnitudes. The amplitude and shape of the resulting light curve is sensitive to the planet's radius and orbital inclination, as well as the composition and size distribution of the scattering particles in the planet's atmosphere. To predict the capabilities of MOST and other planned space missions, we have constructed a series of models of such light curves, improving upon earlier work by incorporating more realistic details such as: limb darkening of the star, intrinsic granulation noise in the star itself, tidal distortion and back-heating, higher angular resolution of the light ...

2003-01-01

360

Regular frequency patterns in the classical delta Scuti star HD 144277 observed by the MOST satellite  

CERN Document Server

We present high-precision time-series photometry of the classical delta Scuti star HD 144277 obtained with the MOST (Microvariability and Oscillations of STars) satellite in two consecutive years. The observed regular frequency patterns are investigated asteroseismologically. HD 144277 is a hot A-type star that is located on the blue border of the classical instability strip. While we mostly observe low radial order modes in classical delta Scuti stars, HD 144277 presents a different case. Its high observed frequencies, i.e., between 59.9c/d (693.9 microHz) and 71.1c/d (822.8microHz), suggest higher radial orders. We examine the progression of the regular frequency spacings from the low radial order to the asymptotic frequency region. Frequency analysis was performed using Period04 and SigSpec. The results from the MOST observing runs in 2009 and 2010 were compared to each other. The resulting frequencies were submitted to asteroseismic analysis. HD 144277 was ...

2011-01-01

361

NMR study of Ba2"+ ion motion in one-dimensional ionic conductor with hollandite-type structure  

International Nuclear Information System (INIS)

Ionic motion of a divalent cation, Ba"2"+, in a single crystal of Ba-Al-priderite was studied using "2"7Al as an NMR probe. Several pairs of satellite peaks due to electric quadrupole interaction were observed superposed on broad satellite tails on both sides of the main peak of "2"7Al. These peak pairs indicate the existence of some stable three-dimensional configurations of Ba"2"+ ions in the structure, and the broad shoulders show a random substitution of Al"3"+ for Ti"4"+ sites. The temperature dependence of the spin-lattice relaxation time T"*_l measured in the temperature range from 161 to 1176 K was analyzed by a curve fitting method on the assumption that there are two types of Ba"2"+ ions. An activation energy of 0.47 eV was obtained for the motion of Ba"2"+ ions which are easy to move, and a broad distribution of activation energies spread over a range from 0.95 to 2.45 eV was obtained for the motion of Ba"2"+ ions which form a ...

362

Monitoring the Effect of Longwall Mining on Agricultural Environments - Interim Report  

Energy Technology Data Exchange (ETDEWEB)

The project was designed to quantify the impacts of longwall mine subsidence (LWMS) on the production and quality of agricultural vegetated environments. This project utilised a variety of traditional ground based sampling techniques including biomass harvests and estimates, leaf area index (LAI), pasture height, species composition and soil sampling along with proximal sensor data capture using a Crop Circle{trademark} and an EM38. Satellite imagery was collected using the Quickbird satellite and the high resolution imagery was used to monitor large areas of LWMS affected areas and adjacent un-mined land. Two landscapes were investigated using a whole of mine site technique including remote sensing, ground survey and traditional agricultural monitoring methods. The landscapes were at the Kestrel site in Emerald, QLD including a forage sorghum and an improved pasture and at Beltana in the Hunter Valley, NSW including an irrigated lucerne ...

2009-06-15

363

Binaries migrating in a gaseous disk: Where are the Galactic center binaries?  

CERN Document Server

The massive stars in the Galactic center inner arcsecond share analogous properties with the so-called Hot Jupiters. Most of these young stars have highly eccentric orbits, and were probably not formed in-situ. It has been proposed that these stars acquired their current orbits from the tidal disruption of compact massive binaries scattered toward the proximity of the central supermassive black hole. Assuming a binary star formed in a thin gaseous disk beyond 0.1 pc from the central object, we investigate the relevance of disk-satellite interactions to harden the binding energy of the binary, and to drive its inward migration. A massive, equal-mass binary star is found to become more tightly wound as it migrates inwards toward the central black hole. The migration timescale is very similar to that of a single-star satellite of the same mass. The binary's hardening is caused by the formation of spiral tails lagging the stars inside the binary's ...

2010-01-01

364

Application of space imagery for the study of anthropogenic pollution and its impact on the environment  

Energy Technology Data Exchange (ETDEWEB)

The implementation of satellite remote sensing data for monitoring anthropogenic pollution in the USSR is described. Space-based monitoring systems offer the opportunity to identify pollution sources, track the spread of pollutants on the surface and in the air, and characterize land use patterns that cause erosion. Furthermore, vegetation under attack by polluting agents can be recognized by color changes, and water pollution in lakes, coastal zones, and in rivers near industrial areas and ports can be measured for the total affected area. The data have thus far been taken with instrumentation on board the Salyut space station, the Meteor-Priroda satellite, and from the Landsat MSS scanner. It is noted that the transboarder transport of pollutants necessitates sharing data with agencies of other nations, and that a data base must be developed to define procedures and instrumentation for given pollutants, algorithms for processing the data, and ...

1983-01-01

365

An Upper Limit on the Albedo of HD 209458b: Direct Imaging Photometry with the MOST Satellite  

CERN Document Server

We present space-based photometry of the transiting exoplanetary system HD 209458 obtained with the MOST (Microvariablity and Oscillations of STars) satellite, spanning 14 days and covering 4 transits and 4 secondary eclipses. The HD 209458 photometry was obtained in MOST's lower-precision Direct Imaging mode, which is used for targets in the brightness range $6.5 < V < 13$. We describe the photometric reduction techniques for this mode of observing, in particular the corrections for stray Earthshine. We do not detect the secondary eclipse in the MOST data, to a limit in depth of 0.053 mmag (1 \\sigma). We set a 1 \\sigma upper limit on the planet-star flux ratio of 4.88 x 10^-5 corresponding to a geometric albedo upper limit in the MOST bandpass (400 to 700 nm) of 0.25. The corresponding numbers at the 3 \\sigma level are 1.34 x 10^-4 and 0.68 respectively. HD 209458b is half as bright as Jupiter in the MOST bandpass. This low geometric albedo value is an ...

2006-01-01

366

The AMPTE program's contribution to studies of the solar wind-magnetosphere-ionosphere interaction  

Energy Technology Data Exchange (ETDEWEB)

The Active Magnetospheric Particle Tracer Explorers (AMPTE) program provided important information on the behavior of clouds of plasma artificially injected into the solar wind and the earth's magnetosphere. Now that the releases are over, data from the satellites are being analyzed to investigate the processes by which the ambient solar wind mass, momentum, and energy are transferred to the magnetosphere. Work in progress at APL indicates that the solar wind is much more inhomogeneous than previously believed, that the solar wind constantly buffets the magnetosphere, and that ground observers may remotely sense these interactions as geomagnetic pulsations. 8 refs.

1990-12-01

367

Solid-state ozone synthesis by energetic ions  

International Nuclear Information System (INIS)

We have synthesized ozone by irradiating thin solid films of oxygen and oxygen-water mixtures with 100 keV protons, motivated by recent reports of condensed O_3 on icy satellites in the outer Solar system. We measured the depth of the Hartley absorption band in the ultraviolet by reflectance spectroscopy and used it to quantify the column density of ozone. We analyzed the results using a three-component (O, O_2 and O_3) model that successfully explains the fluence dependence of ozone production.

1999-08-02

368

Satellite power systems (SPS) concept definition study (exhibit d). Volume 3: transportation analysis. Final report  

Energy Technology Data Exchange (ETDEWEB)

Additional analyses and investigations were conducted to further define transportation system concepts that will be needed for the developmental and operational phases of an SPS program. To accomplish these objectives, transportation systems such as the Shuttle and its derivatives were identified new heavy lift launch vehicle (HLLV) concepts, cargo and personnel orbital transfer vehicles (EOTV and POTV), and intraorbit transfer vehicle (IOTV) concepts were evaluated and, to a limited degree, the program implications of their operations and costs were assessed. The results of these analyses were integrated into other elements of the overall SPS concept definition studies.

1981-03-01

369

Satellite power systems (SPS) concept definition study (exhibit D). Volume 5: systems engineering/integration research and technology. Final report  

Energy Technology Data Exchange (ETDEWEB)

Guidelines and ground rules followed in the development of requirements for the SPS are presented. Development planning objectives are specified in each of these areas, and evolutionary SPS program scenarios are described for the various concepts studied during the past one year contract. Program descriptions are presented as planning packages of technical tasks, and schedule phasing. Each package identifies the ground based technology effort that will facilitate SPS definitions, designs, development, and operations.

1981-03-01

370

Rocket borne solar eclipse experiment to measure the temperature structure of the solar corona via lyman-. cap alpha. line profile observations  

Energy Technology Data Exchange (ETDEWEB)

A rocket borne experiment to measure the temperature structure of the inner solar corona via the doppler broadening of the resonance hydrogen Lyman-..cap alpha.. (lambda1216A) radiation scattered by ambient neutral hydrogen atoms was attempted during the 16 Feb 1980 solar eclipse. Two Nike-Black Brant V sounding rockets carrying instrumented payloads were launched into the path of the advancing eclipse umbra from the San Marco satellite launch platform 3 miles off the east coast of Kenya.

1981-01-01

371

Report on scientific research in geodesy 1987-1991. Soobshchenie o nauchnykh rabotakh po geodezii 1987-1991  

Energy Technology Data Exchange (ETDEWEB)

The symposium reports results of investigations in geodesy conducted between 1987 and 1991 in the Soviet Union. The five sections of the report deal with several aspects of physical geodesy, with particular attention given to studies of the earth's gravitational field; geodetic positioning and geodetic networks; gravimetry, including high-precision gravimetry, marine gravimetry, and nontidal gravity variations; satellite geodesy; and recent crustal movements. Each section is supplied with a detailed bibliography.

1991-01-01

372

RAPID DAMAGE ASSESSMENT FROM HIGH RESOLUTION IMAGERY  

Energy Technology Data Exchange (ETDEWEB)

Disaster impact modeling and analysis uses huge volumes of image data that are produced immediately following a natural or an anthropogenic disaster event. Rapid damage assessment is the key to time critical decision support in disaster management to better utilize available response resources and accelerate recovery and relief efforts. But exploiting huge volumes of high resolution image data for identifying damaged areas with robust consistency in near real time is a challenging task. In this paper, we present an automated image analysis technique to identify areas of structural damage from high resolution optical satellite data using features based on image content.

2008-07-01

373

PAMELA results on the cosmic-ray antiproton flux from 60 MeV to 180 GeV in kinetic energy  

CERN Document Server

The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray antiproton flux and the antiproton-to-proton flux ratio which extends previously published measurements down to 60 MeV and up to 180 GeV in kinetic energy. During 850 days of data acquisition approximately 1500 antiprotons were observed. The measurements are consistent with purely secondary production of antiprotons in the galaxy. More precise secondary production models are required for a complete interpretation of the results.

2010-01-01

374

Localization of highly repetitive, species-specific EcoRI elements from 'Lupinus luteus' L  

International Nuclear Information System (INIS)

Using Southern, dot-blot and 'in situ' hybridization, molecular and cytological localization of repetitive 'Lupinus lueteus' DNA sequence was shown. Under CsCl gradient centrifugation conditions CG-rich satellite fraction appeared. Dot-blot hybridization clearly indicated that 1070bp repetitive element being a member of previously described EcoRI fragments family appeared only in the main band. The use of that DNA fragment as an 'in situ' hybridization signal in the euchromatin area. (author). 26 refs, 3 figs.

375

Financing `Orbital Power and Light Inc`  

Energy Technology Data Exchange (ETDEWEB)

Financing space solar power generation programmes has several inherent difficulties. Such large-scale projects are usually easily defined with an expected economic return, construction time, useful service life and defined management structure. As yet, solar power satellites for power generation possess none of these as the idea exists conceptually and the technology still needs to be developed. Methods for overcoming these uncertainties and securing financial backing are described. Venture capital could finance a research/marketing firm. US Government support through a cost plus short-term monopoly to facilitate private debt financing could provide an answer. (UK)

1998-06-01

376

FORTE antenna element and release mechanism design  

Energy Technology Data Exchange (ETDEWEB)

The Fast On-Orbit Recording of Transient Events (FORTE) satellite being built by Los Alamos National Laboratory (LANL) and Sandia National Laboratories (SNL) has as its most prominent feature a large deployable (11 m by 5 m) log periodic antenna to monitor emissions from electrical storms on the Earth. This paper describes the antenna and the design for the long elements and explains the dynamics of their deployment and the damping system employed. It also describes the unique paraffin-actuated reusable tie-down and release mechanism employed in the system.

1995-02-01

377

Development of ARIES Baker-Nunn camera to a wide-field Imaging Telescope with CCD  

CERN Document Server

ARIES Baker-Nunn Schmidt telescope project is converting a Baker-Nunn satellite tracking camera for Astronomical research. Original Baker-Nunn camera produces an extremely large (5X30 degree) curved focal plane at the prime focus for photographic imaging. We present here the re-designing of the camera produces a wide (4 X 4 degree) flat field of view for CCD imaging observations, which have many scientific potentials in Astronomy. Imaging performance of the CCD camera is also estimated.

2009-01-01

378

Computer vision approaches to medical image analysis. Revised papers  

Energy Technology Data Exchange (ETDEWEB)

This book constitutes the thoroughly refereed post proceedings of the international workshop Computer Vision Approaches to Medical Image Analysis, CVAMIA 2006, held in Graz, Austria in May 2006 as a satellite event of the 9th European Conference on Computer Vision, EECV 2006. The 10 revised full papers and 11 revised poster papers presented together with 1 invited talk were carefully reviewed and selected from 38 submissions. The papers are organized in topical sections on clinical applications, image registration, image segmentation and analysis, and the poster session. (orig.)

2006-07-01

379

Computer model of high-latitude scintillation. [WBMOD program  

Energy Technology Data Exchange (ETDEWEB)

The DNA Wideband satellite experiment provided extensive data on scintillation produced in high-altitude structured plasmas. A computer program, WBMOD, is being developed to summarize those data in an applications-oriented way. The program contains the phase-screen scattering theory of Rino and a morphological description of ionospheric irregularities (thus far only at auroral latitudes) based on Wideband observations. It permits a user to compute scintillation indices for both phase and intensity as a function of system operating parameters and solar-ionospheric disturbance level. Correction is made for multiple scatter, and the user may choose either one-way (communication) or two-way (radar) propagation.

1982-01-01

380

Computer model of high-latitude scintillation  

International Nuclear Information System (INIS)

The DNA Wideband satellite experiment provided extensive data on scintillation produced in high-altitude structured plasmas. A computer program, WBMOD, is being developed to summarize those data in an applications-oriented way. The program contains the phase-screen scattering theory of Rino and a morphological description of ionospheric irregularities (thus far only at auroral latitudes) based on Wideband observations. It permits a user to compute scintillation indices for both phase and intensity as a function of system operating parameters and solar-ionospheric disturbance level. Correction is made for multiple scatter, and the user may choose either one-way (communication) or two-way (radar) propagation.

381

Assessing NDVI Spatial Pattern as Related to Irrigation and Soil Salinity Management in Al-Hassa Oasis, Saudi Arabia  

British Library Electronic Table of Contents (United Kingdom)

Sustainability of irrigated agriculture in arid and semi arid lands depends, mainly on the level of soil salinity and the quality of irrigation water. Remotely sensed data can provide information about the extent of vegetated irrigated areas. Al-Hassa oasis, Saudi Arabia is probably the largest oasis in the world depends mostly on tapped ground water to irrigate mainly date palm groves for its economic survival. This study tried to investigate the extent of soil salinity and the quality of irrigation water and the relationship with vegetation growth, employing NDVI derived from Landsat satellite imagery.

2011-01-01

382

Aerosol Properties Over the United Arab Emirates and Arabian Gulf from MISR Multi-angle Satellite Imaging  

Science.gov (United States)

The MISR instrument aboard NASA's Terra satellite participated in the UAE-2 campaign, August-October 2004. This campaign represented a unique opportunity to study the complex aerosol situation in the Arabian Gulf region, in the context of a first-rate collection of aircraft and surface-based instruments, giving us the opportunity to do some groundbreaking satellite aerosol validation work. We aimed (1) to validate MISR aerosol retrieval results for dust and pollution particles over dark and light surfaces, and (2) to contribute regional maps of aerosol optical thickness (AOT) and particle micro-physical properties, giving spatial context to the field-instrument measurements, and moving toward a satellite-based regional aerosol climatology. The validation effort benefited from the combination of an instrumented aircraft and a regional network of surface-based sun photometers. We obtained high-quality sub-orbital data ...

2005-12-01

383

The Infrared Camera (IRC) for the ASTRO-F infrared astronomical satellite  

Science.gov (United States)

The Infrared Camera (IRC) is one of the scientific focal plane instruments on board the ASTRO-F infrared astronomical satellite. The IRC is designed for wide field imaging and slit-less spectroscopic observations at near- and mid-infrared wavelengths. The IRC consists of three channels; NIR, MIR-S and MIR-L, each of which covers wavelengths of 2-5, 5-12 and 12-26 micron, respectively. All channels adopt compact refractive optical designs. Large format array detectors (a InSb 512 x 412 array and two Si:As IBC 256 x 256 arrays) are employed. Each channel has 10 x 10 arcminutes wide FOV with diffraction-limited angular resolution of 70cm aperture of the liquid helium cooled telescope at wavelengths over 5 micron. A 6-position filter wheel is placed at the aperture stop in each channel, and has three band-pass filters, two grisms/prisms and a mask for dark current measurements. The 5 sigma sensitivity of one pointed observation is estimated to be 2, 11 and 62 micro-Jy ...

2004-01-01

384

Secure data communication for safeguards implementation  

International Nuclear Information System (INIS)

Full text: Secure, reliable and cost-effective communications are becoming an increasingly important tool for safeguards verification. This trend began with the initiation of remote monitoring implementation, where secure and cost effective data communications were required both to satisfy the confidentiality requirements of Member States and in order to meet the rigorous data authenticity requirements which allow the International Atomic Energy Agency (IAEA) to draw credible and independent conclusions. In addition, the implementation of additional protocols and integrated safeguards increases the importance of information (obtained in the course of an inspection, visit, complementary access or design information verification) being analyzed and corroborated with other information sources stored at IAEA Headquarters or Regional Offices, often while the inspector is still on-site. This requires the capability of enabling the inspector, wherever he is in the field, to communicate with ...

2006-10-16

385

GOCE, Satellite Gravimetry and Antarctic Mass Transports  

Science.gov (United States)

In 2009 the European Space Agency satellite mission GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) was launched. Its objectives are the precise and detailed determination of the Earth's gravity field and geoid. Its core instrument, a three axis gravitational gradiometer, measures the gravity gradient components V xx , V yy , V zz and V xz (second-order derivatives of the gravity potential V) with high precision and V xy , V yz with low precision, all in the instrument reference frame. The long wavelength gravity field is recovered from the orbit, measured by GPS (Global Positioning System). Characteristic elements of the mission are precise star tracking, a Sun-synchronous and very low (260 km) orbit, angular control by magnetic torquing and an extremely stiff and thermally stable instrument environment. GOCE is complementary to GRACE (Gravity Recovery and Climate Experiment), another satellite gravity mission, ...

2011-03-01

386

White luminescence of Tm-Dy ions co-doped aluminoborosilicate glasses under UV light excitation  

International Nuclear Information System (INIS)

Tm3+ and Dy3+ ions co-doped aluminoborosilicate glasses were prepared in this study. The luminescence properties of the glasses were analyzed. A combination of blue, green, yellow, and red emission bands was shown for these glasses, and white light emission could be observed under UV light excitation. White light luminescence color could be changed by varying the excitation wavelength. Concentration quenching effect was investigated in this paper. Furthermore, the dependence of luminescence properties on glass compositions was studied. Results showed that the luminescence intensity changed with different network modifier oxides, while the white color luminescence was not affected significantly. - Graphical abstract: Tm3+ and Dy3+ ions co-doped aluminoborosilicate glasses, which emit white light under UV light excitation, were prepared. The dependence of luminescence properties on glass compositions was studied, and results ...

2008-10-01

387

Upper bound for a three-photon excitation cross section in atomic argon in the ultraviolet regime  

Energy Technology Data Exchange (ETDEWEB)

A scheme of evaluating a generalized three-photon excitation cross section sigma/sub (3)/ in neutral atomic argon at 3144.67 A is outlined. Three photons at this wavelength can excite the neutral argon atoms from the ground 3p/sup 6/ /sup 1/S/sub 0/ state to the 3p/sup 5/4s'(1/2)/sub 1//sup 0/ state. The fourth photon will ionize the argon atoms. Assuming linear polarization of the incident laser radiation, contributions from several channels in various energy-level schemes are summed in the evaluation of the transition probability. For a laser linewidth of ..delta..lambda/sub L/ = 1 A, our maximum numerical value of the computed result for the three-photon excitation cross section is sigma/sub (3)/ = 1.414 x 10/sup -80/ cm/sup 6/ s/sup 2/. .AE

1989-04-15

388

Statistical treatment of the inner M-shell excitation in heavy ion-atom collisions  

Energy Technology Data Exchange (ETDEWEB)

A statistical treatment has been applied to interpret the experimental data on the Xe M-shell vacancy production in slow 1.05 MeV Xe-Xe collisions and is shown to give better agreement with experiment than that of the molecular-orbital models.

1983-06-27

389

Simulation study of chiral two dimensional ultraviolet (2DUV) spectroscopy of the protein backbone  

UK PubMed Central (United Kingdom)

Amide n –π* and π-π* excitations around 200 nm are prominent spectroscopic...Full Text Available

2010-06-09

390

Selected results in hadron structure from lattice QCD  

Energy Technology Data Exchange (ETDEWEB)

I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method.

2006-03-15

391

Selected results in hadron structure from lattice QCD  

International Nuclear Information System (INIS)

I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method.

2006-03-01

392

Protracted withdrawal from alcohol and drugs of abuse impairs long-term potentiation of intrinsic excitability in the juxtacapsular bed nucleus of the stria terminalis  

UK PubMed Central (United Kingdom)

The juxtacapsular BNST (jcBNST) is activated in response to basolateral amygdala (BLA) inputs through the stria terminalis and projects back to the anterior BLA and to the central nucleus of...Full Text Available

2009-04-29

393

Photochemistry and charge transfer chemistry of the platinum group elements  

Energy Technology Data Exchange (ETDEWEB)

During the past 3 years, progress was made in elucidating the excited state structures of Pt(diimine)(dithiolate) complexes, while more recent efforts focused on the photochemistry of these complexes and electronic structure of other dithiolate systems. A carbonyl-Ir-maleonitrile dithiolate complex is also studied.

1992-12-01

394

On-line nuclear orientation. Progress report, April 1, 1991--March 31, 1992  

Energy Technology Data Exchange (ETDEWEB)

This report discusses: shape coexistence in {sup 184}Pt; nuclear structure of {sup 187}Ir; g-factors of excited states; OLNO-2; and refrigerator development.

1992-06-01

395

Nucleon resonance studies in phenomenological analysis of the CLAS  

Energy Technology Data Exchange (ETDEWEB)

First comprehensive data on the evolution of nucleon resonance photocouplings with photon virtuality Q{sup 2} are presented for excited proton states in the mass range from 1.4 to 2.0 GeV.

2006-07-01

396

Modular control of human walking: Adaptations to altered mechanical demands  

UK PubMed Central (United Kingdom)

Studies have shown that the nervous system may adopt a control scheme in which synergistic muscle groups are controlled by common excitation patters, or modules, to simplify the coordination...Full Text Available

2010-02-10

397

Measurements of the Alfven wave spectrum in TCA  

International Nuclear Information System (INIS)

The modular and periodic antenna structure in TCA is shown to produce an extremely pure spectrum of excited waves. This purity, together with precise measurements of the antenna loading in different parts of the spectrum, has allowed us to demonstrate that it is essential to include both toroidal coupling and the Hall effect (#omega#/#omega#/sub c//sub i/not =0) in order to explain our results. We show that toroidicity produces coupling from the directly excited Vertical BarmVertical Bar = 1 wave to Vertical BarmVertical Bar = 0,2 waves. Discrete Alfven Waves are also seen for Vertical BarmVertical Bar = 0,2 in addition to the directly driven Vertical BarmVertical Bar = 1. The importance of the Hall effect is most visible when a travelling wave is excited, in which case the antenna loading depends on the direction of the wave imposed. We present the antenna loading found with different excitation ...

1985-05-13

398

Magnetic excitations studied with time-of-flight spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

An introduction to time-of-flight neutron spectroscopy is presented in the context of the study of magnetic materials. Examples are taken from the class of rare earth and actinide magnetic materials known as `strongly correlated electron` systems. (author) 11 figs., 24 refs.

1996-11-01

399

Long-term synaptic transformation of hippocampal CA1 gamma-aminobutyric acid synapses and the effect of anandamide.  

UK PubMed Central (United Kingdom)

Evidence is presented for a distinctive type of hippocampal synaptic modification [previously described for a molluscan gamma-aminobutyric acid (GABA) synapse after paired pre- and postsynaptic excitation]:...Full Text Available

1995-10-24

400

Long-lived quantum coherence in photosynthetic complexes at physiological temperature  

UK PubMed Central (United Kingdom)

Photosynthetic antenna complexes capture and concentrate solar radiation by transferring the excitation to the reaction center that stores energy from the photon in chemical bonds. This process occurs...Full Text Available

2010-07-20

401

LED Arrays as Cost Effective and Efficient Light Sources for Widefield Microscopy  

UK PubMed Central (United Kingdom)

New developments in fluorophores as well as in detection methods have fueled the rapid growth of optical imaging in the life sciences. Commercial widefield microscopes generally use arc lamps, excitation/emission...Full Text Available

402

Isotopic analysis of lithium by hollow cathode excitation  

Energy Technology Data Exchange (ETDEWEB)

A method for quick, high-accuracy measurement of lithium isotopes has become necessary in carrying out research on the separation and concentration of lithium isotopes by ion exchange. The present report focuses on the application of a hollow cathode, as excitation source, to emission spectral analysis for lithium isotope measurement. The grating monochromator used incorporates a pressure scanned etalon. With decreased Doppler broadening and pressure broadening, the hollow cathode, used as excitation source, can give narrow spectral lines, permitting good separation among them. To achieve a high accuracy, the emission intensity of the hollow cathode should be maintained as stable as possible relative to time. In particular, the stability of a light source can be affected significantly by the chemical form of the sample. A study is also made here to identify a condition where lithium acetate effluent as-obtained from an ion exchange column can ...

1990-04-01

403

Investigation of novel organic n-type semiconductors in photovoltaic bulk heterojunction  

Energy Technology Data Exchange (ETDEWEB)

Two novel organic n-type semiconductors are investigated due to their function as electron acceptor for applications in organic electronic devices to widen the knowledge of how molecule structure influences the excitation processes in organic electronics. Bispyrenylfullerene and Octadecyl-Capronacidesterfullerene are C{sub 60} derivates with sidechains more featured compared to the commonly used[6,6] phenyl-C{sub 61}-butyric acid methyl ester (PCBM). In bulk heterojunction devices regioregular poly(3-hexylthiophene) (P3HT) was used as donor. The materials, pristine and in blend, were studied in view of light absorption, their quenching abilities of the P3HT photoluminescence as well as excited states. Furthermore, the spin state of the excited states was determined by light-induced electron spin resonance. Combining these complimentary experimental techniques, we obtained information on the generation of ...

2009-07-01

404

Initial Development and Characterization of PLGA Nanospheres Containing Ropivacaine  

UK PubMed Central (United Kingdom)

Local anesthetics are able to induce pain relief by binding to the sodium channels of excitable membranes, blocking the influx of sodium ions and the propagation of the nervous impulse. Ropivacaine...Full Text Available

2007-12-01

405

Images of photoreceptors in living primate eyes using adaptive optics two-photon ophthalmoscopy  

UK PubMed Central (United Kingdom)

In vivo two-photon imaging through the pupil of the primate eye has the potential to become a useful tool for functional imaging of the retina. Two-photon excited fluorescence images...Full Text Available

406

Homeostasis of intrinsic excitability in hippocampal neurones: dynamics and mechanism of the response to chronic depolarization  

UK PubMed Central (United Kingdom)

In order to maintain stable functionality in the face of continually changing input, neurones in the CNS must dynamically modulate their electrical characteristics. It has been hypothesized that in...Full Text Available

2010-01-01

407

Heat Transfer Augmentation in Turbulent Impinging Jets.  

Science.gov (United States)

Heating and cooling by impinging jets is widely used in various engineering applications, due to the high heat transfer rates prevailing in the vicinity of the stagnation point. The authors have been able to utilize acoustically excited turbulence for the...

1979-01-01

408

Generalized ladder operators for the Dirac-Coulomb problem via SUSY QM  

Energy Technology Data Exchange (ETDEWEB)

The supersymmetry in quantum mechanics and shape invariance condition are applied as an algebraic method to solving the Dirac-Coulomb problem. The ground state and the excited states are investigated via new generalized ladder operators. (author)

2003-12-15

409

Excitations and electromagnetic transitions for /sup 88/Sr and /sup 90/Zr  

Energy Technology Data Exchange (ETDEWEB)

In this letter we report the outcome for the microscopic approach for the semi-magic nuclei /sup 88/Sr and /sup 90/Zr. For comparison, we have also treated the semi-phenomenological version for the Migdal and SDI force.

1981-10-10

410

Excitations and electromagnetic transitions for /sup 88/Sr and /sup 90/Zr  

Energy Technology Data Exchange (ETDEWEB)

An application of the renormalized random phase approximation to nuclear structure is presented for the semi-magic nuclei /sup 88/Sr and /sup 90/Zr. It is reported the outcome for the microscopic approach in comparison with the semiphenomenological version for the particle-hole forces.

1981-10-10

411

Effects of Naja nivea venom on nerve, cardiac and skeletal muscle activity of the frog  

UK PubMed Central (United Kingdom)

1. The effects of 1 mg/ml whole Naja nivea (Cape cobra) venom, and of three different toxins isolated from it, on spinal reflex excitability and cardiac and skeletal muscle activity...Full Text Available

1973-03-01

412

Dendritic Signals Command Firing Dynamics in a Mathematical Model of Cerebellar Purkinje Cells  

UK PubMed Central (United Kingdom)

AbstractDendrites of cerebellar Purkinje cells (PCs) respond to brief excitations from parallel fibers with lasting plateau depolarizations. It is unknown whether these plateaus are local...Full Text Available

2010-07-21

413

Age-dependent changes in Ca2+ homeostasis in peripheral neurones: implications for changes in function  

UK PubMed Central (United Kingdom)

Calcium ions represent universal second messengers within neuronal cells integrating multiple cellular functions, such as release of neurotransmitters, gene expression, proliferation, excitability,...Full Text Available

2007-06-01

414

Steady-state levels of G-protein beta-subunit expression are regulated by treatment of cells with bacterial toxins  

International Nuclear Information System (INIS)

Cultures of 3T3-L1 cells were incubated with either 10 ng/ml cholera toxin or 10 ng/ml pertussis toxin from 4 days prior to the initiation of differentiation and throughout the subsequent incubation. Toxin concentrations were sufficient to completely prevent the labelling of alpha-subunits with ["3"2P]NAD"+ and pertussis toxin and to prevent by more than 90% the labelling with ["3"2P]NAD"+ and cholera toxin in membranes prepared from these cells. Neither toxin prevented the differentiation to the adipocyte phenotype. Neither toxin prevented the increases in the relative amounts of G-proteins which occur upon differentiation. Both toxins dramatically decreased the amount of beta-subunits. As measured by quantitative immunoblotting with antisera specific for both the 35 kDa and 36 kDa beta-subunits, levels of beta-subunit were decreased by more than 50% of steady-state level of control cells. Thus, ...

1987-06-07

415

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 ...

2009-05-01

416

NMR in highly correlated superconductors  

International Nuclear Information System (INIS)

Results of our systematic NMR study in high T_c cuprates are reviewed. The antiferromagnetic spin fluctuations (AFSF) decrease in the order of La_1_._8_5Sr_0_._1_5CuO_4. YBa_2Cu_3O_7 and Tl_2Ba_2CuO_6_+_y. 1/T_1 of "6"3Cu in the CuO_2 plane in the normal state follows essentially a Curie-Weiss law at high temperature and T_1T = const. law at low temperature. The temperature dependence of 1/T_1 and the Knight shift together with their impurity effect in the superconducting state strongly suggest d-wave pairing implying the AFSF to be responsible for the occurrence of superconductivity. From the NQR frequency measurement the density of Cu 3d and O 2p holes decreases and increases, respectively, in the order of La, Y and Tl compounds, which is consistent with the change of AFSF. The relation between T_c and #nu#_Q, and their pressure dependence suggest that there exists and optimum value of the ratio of Cu 3d and O ...

1992-08-01

417

Is the 4.742 MeV state in {sup 88}Sr the 1{sup -} two-phonon state?  

Energy Technology Data Exchange (ETDEWEB)

A nuclear resonance fluorescence experiment on {sup 88}Sr has been performed with bremsstrahlung of 6.7 MeV endpoint energy. The {gamma}-ray linear polarisation has been measured with a EUROBALL CLUSTER detector used as a Compton polarimeter. The results indicate positive parity for the J=1 state at 4.742 MeV in {sup 88}Sr, in contrast to the previous interpretation as a 1{sup -} two-phonon (2{sup +}{sub 1} x 3{sup -}{sub 1}) state and in conflict with the predictions of the quasiparticle-phonon model. On the basis of such calculations the 1{sup +} state at 3.486 MeV may be considered as the 1{sup +}{sub 1} one-phonon state and the very strong 1{sup +}{sub 1}{yields}0{sup +}{sub 1} deexcitation as proton spin-flip 2p{sub 1/2}{yields}2p{sub 3/2} transition. (orig.)

2000-01-01

418

Differentiation to adipocytes in accompanied by an increase in the amounts of Gi- and Go-proteins in 3T3-L1 cells  

International Nuclear Information System (INIS)

Treatment of cultures of 3T3-L1 cells with methylisobutyl-xanthine and dexamethasone has been shown to result in accumulation of lipid and conversion to the morphology of adipocytes in more than 90% of the cells. The status of the stimulatory (Gs), inhibitory (Gi) and Go-proteins during the course of 3T3-L1 differentiation was examined. The amount of alpha subunit of Gs (#alpha#Gs), assayed by radiolabeling in the presence of cholera toxin and ["3"2P]NAD"+, increased upon differentiation as previously described by others. The amounts of #alpha#Gi and #alpha#Go assayed by radiolabeling in the presence of pertussis toxin and ["3"2P]NAD"+ increased 3-fold upon differentiation. Immunoblots of cell membranes subjected to gel electrophoresis in sodium dodecyl sulfate were probed with two rabbit antisera raised against bovine brain #alpha#Go and with one raised against the#beta#-subunit of the bovine ...

1986-06-08

419

Decay of the Ar 2s"-"1 and 2p"-"1 and Kr 3p"-"1 and 3d"-"1 hole states studied by photoelectron-ion coincidence spectroscopy  

International Nuclear Information System (INIS)

The decay channels of the Ar 2s"-"1 and 2p"-"1 and Kr 3p"-"1 and 3d"-"1 electronic hole states have been investigated by means of photoelectron-photoion coincidence measurements following innershell ionization using synchrotron radiation. With the method of final ion-charge resolving electron spectroscopy it has become possible to disentangle different contributions to the electron spectrum and to determine the decay probabilities P(nl"-"1#->#n+) of the above-mentioned hole states (nl"-"1) to the final ionic charge states n+. A high correlation with threefold or even fourfold charged ions has been found in all cases. Possible decay routes, via cascade or direct double Auger processes, are discussed on the basis of energy-level schemes calculated with the Hartree-Fock method. Special emphasis is laid on the examination of the Kr 3p"-"1 decay process, where the two fine-structure components (j=1/2,3/2) exhibit noticeably different decay ...

2002-04-01

420

Crystalline O,O'-di-sec-butyl and O,O'-diethyl dithiophosphate platinum(II) complexes: Synthesis, 13C and 31P CP/MAS NMR, single crystal X-ray diffraction studies and thermal behaviour  

British Library Electronic Table of Contents (United Kingdom)

Crystalline bis(O,O'-di-sec-butyldithiophosphato)platinum(II) was prepared and studied by means of 13C, 31P CP/MAS NMR spectroscopy and single-crystal X-ray diffraction. The unit cell of the platinum(II) compound is comprised of one centrosymmetric mononuclear molecule [Pt{S2P(O-sec-C4H9)2}2], in which the dithiophosphate groups display structural equivalence in both 31P NMR and XRD data. A pair of the dithiophosphate ligands exhibit the same S,S'-bidentate chelating structural function and form two planar four-membered chelate rings, [PtS2P], in this molecule. The planar configuration of the [PtS4] chromophore in structure 1 is governed by the dsp2-hybrid state of platinum(II). The structural states of the dithiophosphate groups in two different samples of complex 1 (one crystallised from...

2011-01-01

421

Spectroscopy of light exotic nuclei  

International Nuclear Information System (INIS)

Neutron-rich He-, Li-, and Be-isotopes in the vicinity of the drip-line have been studied by "1"2C- and "1"4C-induced multi-nucleon transfer reactions on "1"0Be and "1"3","1"4C-targets. This study revealed unknown excited states in "8","1"0He, "1"0","1"1Li and in "1"3","1"4Be. Both excitation energies and widths have been measured. In some cases most probable spins and parities could be assigned to the particle-unstable states observed. (orig.).

1996-01-15

422

Simulation of statistical {gamma}-spectra of highly excited rare earth nuclei  

Energy Technology Data Exchange (ETDEWEB)

The statistical {gamma}-spectra of highly excited even-even rare earth nuclei are simulated applying appropriate level density and strength function to a given nucleus. Hindrance effects due to K-conservation are taken into account. Simulations are compared to experimental data from the {sup 163}Dy({sup 3}He,{alpha}){sup 162}Dy and {sup 173}Yb({sup 3}He,{alpha}){sup 172}Yb reactions. The influence of the K quantum number at higher energies is discussed. 21 refs., 7 figs., 2 tabs.

1997-05-01

423

Quenching of the electron scattering form factor of the 1/sup +/ state at 3. 48 MeV in /sup 88/Sr and the influence of the. delta. (1232)-isobar  

Energy Technology Data Exchange (ETDEWEB)

The form factor for excitation of the 1/sup +/ state at 3.48 MeV in /sup 88/Sr by inelastic electron scattering has been measured for momentum transfers q = 0.24-0.62 fm/sup -1/. Neither its magnitude nor shape can be described employing the best available nuclear wave functions. We demonstrate with a schematic model that the observed reduction of the form factor may be understood by taking into account a renormalization of the M1-operator due to virtual ..delta..-hole excitations.

1982-04-01

424

Quenching of the electron scattering form factor of the 1"+ state at 3.48 MeV in "8"8Sr and the influence of the #DELTA#(1232)-isobar  

International Nuclear Information System (INIS)

The form factor for excitation of the 1"+ state at 3.48 MeV in "8"8Sr by inelastic electron scattering has been measured for momentum transfers q = 0.24-0.62 fm"-"1. Neither its magnitude nor shape can be described employing the best available nuclear wave functions. We demonstrate with a schematic model that the observed reduction of the form factor may be understood by taking into account a renormalization of the M1-operator due to virtual #DELTA#-hole excitations. (orig.).

425

Quantum electrodynamic and semiclassical interference effects in spontaneous radiation  

International Nuclear Information System (INIS)

The theory of spontaneous decay is studied using both quantum electrodynamics (QED) and semiclassical theories of radiation. There are qualitative differences between the theories in the prediction of interference phenomena. In QED, systems which were excited with pulsed laser light do not exhibit quantum interference effects associated with lower state splittings. On the other hand, semiclassical treatments of spontaneous decay do indicate the existence of interference effects not present in QED. In addition to this, differences are found between the predictions of fluorescence intensity in the presence of lower-state level crossings under continuous excitation. (U.S.).

1975-01-01

426

Possible influence of vacuum polarization on Q/sub 1//sub //sub s/ in muon catalyzed D-T fusion  

Energy Technology Data Exchange (ETDEWEB)

The vacuum polarization splitting of the M-shell states in muonic hydrogen can have a profound influence on the muonit de-excitation cascade in deuterium and tritium targets. The cascade also shows sensitive dependence on the precise rate of transfer processes between certain excited muonic deuterium and tritium atoms. Recent experimental data, where a much greater population of the (d..mu..) qs state (1/sub 1//sub //sub s/) was found than previously predicted, can be explained if the transfer rates from the (d..mu..) M-shell are assumed to be strongly suppressed.

1988-12-27

427

Particle-hole excitations in N=50 nuclei  

Energy Technology Data Exchange (ETDEWEB)

Energy levels in N=50 nuclei are calculated allowing single-particle excitations from the p{sub 1/2} and g{sub 9/2} shells into the d{sub 5/2}, s{sub 1/2}, d{sub 3/2}, and g{sub 7/2} shells. Important parts of the interaction are determined by least-squares fits to known levels. Agreement with experiment is very good. The high-spin particle-hole states appear to be mainly yrast levels in mass 93 and higher, but are not in {sup 90}Zr. {copyright} {ital 1997} {ital The American Physical Society}

1997-03-01

428

Optogalvanic isotope enrichment of Cu ions in Cu-Ne positive column discharges  

Energy Technology Data Exchange (ETDEWEB)

The isotopic enrichment of copper ions in a positive column Cu-Nu discharge using optogalvanic excitation is analyzed with a rate equation model With excitation at 510.6 nm, the fraction of the ions belonging to the 63-amu isotope of copper is enriched relative to the neutral abundance. Enrichment as large as 10% is calculated when the initial abundance of the neutral isotope is small (< or =0.1) and the discharge current density is large (> or =75 mA/cm/sup 2/). The degree of enrichment is examined as a function of the initial abundance, discharge current, the rate of charge exchange, and the diameter of the discharge tube.

1983-07-01

429

On vortices heating biological excitable media  

International Nuclear Information System (INIS)

An extension of the Hodgkin-Huxley mathematical model for the propagation of nerve signal which takes into account dynamical heat transfer in biological tissue is derived and fine tuned with existing experimental data. The medium is heated by Joule's effect associated with action potential propagation, leading to characteristic thermal patterns in association with spiral and scroll waves. The introduction of heat transfer-necessary on physical grounds-provides a novel way to directly observe the movement, regular or chaotic, of the tip of spiral waves in numerical simulations and possibly in experiments regarding different biological excitable media.

2009-11-30

430

Occurrence of magnetism in superconductors  

Science.gov (United States)

We discuss how magnetic phenomena affect superconductivity in simple metals, transition metals and alloys thereof, and dilute Rare-Earth alloys. It is shown both qualitatively and quantitatively that superconductors are sensitive probes for studying itinerant spin excitations, local spin excitations associated with nearly magnetic impurities, the effect of the atomic environment on the stability of local magnetic moments, and the nature of the spin order in Rare-Earth alloys. Also, we discuss how magnetic impurities can be used to study the electronic configuration which is responsible for superconductivity in Laves-phase crystals like A-15 compounds and ..beta..-W crystals, for example.

1970-12-14

431

Nonlinear vibrations and chaos in electrostatic torsional actuators  

British Library Electronic Table of Contents (United Kingdom)

Electrostatic torsional micro-mirrors have wide spread use in different industries for diverse purposes. This paper investigates the development of superharmonics and chaotic responses in electrostatic torsional micro-mirrors near the pull-in condition. Appearance of nonlinear phenomena is investigated in models accounting for and disregarding the coupling of torsional and flexural deflections. Analysis of the system response to step and harmonic excitation reveals the appearance of DC and AC symmetry breaking. Increasing the amplitude of harmonic excitation, the response in the form of distinct superharmonics changes to a broad band response, where there is loss of periodicity and the response becomes chaotic. Accounting for flexural deflections in coupled model reduces the voltage thresh...

2011-01-01

432

Modular symmetry in parametrically excited quantum oscillators  

Energy Technology Data Exchange (ETDEWEB)

It is shown that when a quantum mechanical oscillator is parametrically excited there are special values of the parameters for which the system will pass periodically through a lattice of coherent states associated with the modular group [Gamma]. It is shown that these [Gamma] transits can be used to determine unknown parameters. A method is given for detecting the transits experimentally and is made possible by the existence of three families of states associated with modular forms that are orthogonal to the lattice. For isotropic states the three families occur in [ital D]-mode systems with [ital D][gt]10, 14, and 26.

1993-11-29

433

Measurement of liquid xenon scintillation from heavy ions using a silicon photodiode  

Energy Technology Data Exchange (ETDEWEB)

Scintillation light in liquid xenon excited by 100 MeV/n Al ions was detected with a home-made silicon photodiode. The diameter of the photodiode was 2 inch. The effective quantum efficiency was observed to be 22% for the wavelength of liquid xenon scintillation light (170 nm), while the effective quantum efficiency for 5.486 MeV alpha-particle excitation was 44%. An energy resolution of 0.5% rms was achieved for the energy deposition of 2.5 GeV in liquid xenon using a fast preamplifier ({approx equal} 20 ns). (orig.).

1991-11-15

434

Magnetic excitations in the antiferromagnetic Kondo compound CePd sub 2 Si sub 2  

Energy Technology Data Exchange (ETDEWEB)

The magnetic excitations of the Kondo compound CePd{sub 2}Si{sub 2} below its Neel temperature (T{sub N} = 10 K) have been studied by inelastic neutron scattering. At T = 1.6 K the data are best represented by two dispersive inelastic modes. Their linewidth ({proportional to} 0.5 meV) indicates substantial broadening, which is ascribed to Kondo-type local fluctuations. (orig.).

1992-02-01

435

Level density parameter and fission probability calculations in heavy-ion-induced fission reactions  

International Nuclear Information System (INIS)

Based on the single-particle levels given by Nilsson, the intrinsic and effective (with collective effects) level density parameters as a function of the excitation energy for the "1"8"6Os, "1'8"7Ir, "1"8"9Os and "1"9"3Au deformation nuclei have been calculated in the range of the excitation energy up to 150 MeV. The calculated fission probabilities P_f (U) are consistent satisfactorily with the experimental data when a nonadiabatic estimation of the collective effects was used to calculated the nuclear level density parameters.

436

Ionization and recombination rates in non-Maxwellian plasmas  

Science.gov (United States)

The ionization, excitation, and radiative recombination rates for highly stripped ions are cal- culated with Maxwellian and non-Maxwellian electron distribution functions of the type Cmexp(-vm/wm) (2<=m<=5) as encountered in laser-heated plasmas and certain types of turbulent plasmas. The direct-radiative-recombination rates are found to decrease by at most 30% as m is increased from 2 to 5. On the other hand, the ionization and excitation rates are found to be strongly reduced if the transition energy ? exceeds twice the local temperature kBTe. The effect of this on the distribution of energy levels and degrees of ionization in laser-produced plasmas could be important.

1986-08-01

437

Influence of UMTS mobile phone microwave fields on the muscular system; Einfluss von Mikrowellenfeldern des UMTS Mobilfunks auf das muskulaere System  

Energy Technology Data Exchange (ETDEWEB)

Two hypotheses are in the centre of this investigation, on the one hand the question, whether microwaves as exogenous fields alone are able to stimulate human muscle cells above-threshold, and on the other hand, whether microwaves as conditioning to cathodical electrical pulses can modify the excitation threshold and form. No excitation through the application of microwaves alone can be introduced at any subject. The conditioning of above-threshold cathodical electrical pulses with UMTS-microwaves leads not to a transgression of the threshold or the electrical muscle response (EMG) depending on the amplitude, the duration or the dose rate. (orig.)

2004-07-01

438

Excitation of the 2_1"+ and 2_2"+ states in the "8"8Sr(p,p') reaction at 25 and 31 MeV: A look behind the nuclear surface  

International Nuclear Information System (INIS)

Data for the excitation of the 2_1"+ and 2_2"+ states in the "8"8Sr(p,p') reaction at 25 and 31 MeV indicate sustantial contributions from the interior of the nucleus, Microscopic DWBA calculations reproduce this and yield a fair description of the data. A detailed description, especially of the 2_2"+ state, is sensitive to the effective nucleon-nucleon interaction used and the non-locality of the optical potential, which are insufficiently known at present. (orig.).

439

Excitation of the 2/sub 1//sup +/ and 2/sub 2//sup +/ states in the /sup 88/Sr(p,p') reaction at 25 and 31 MeV: A look behind the nuclear surface  

Energy Technology Data Exchange (ETDEWEB)

Data for the excitation of the 2/sub 1//sup +/ and 2/sub 2//sup +/ states in the /sup 88/Sr(p,p') reaction at 25 and 31 MeV indicate sustantial contributions from the interior of the nucleus, Microscopic DWBA calculations reproduce this and yield a fair description of the data. A detailed description, especially of the 2/sub 2//sup +/ state, is sensitive to the effective nucleon-nucleon interaction used and the non-locality of the optical potential, which are insufficiently known at present.

1986-07-03

440

Excitation of Plasma Fluctuations near ion Giro frequencies during RF Plasma Heating in URAGAN-3M Torsatron  

International Nuclear Information System (INIS)

Currentless plasma in Uragan-3M (U-3M) is produced and heated by absorption of RF power in the region of Alfven waves (AW). The process of plasma heating was explained in (2) as a result of Cherenkov absorption of energy of the fast (EM) and slow (kinetic Alfven) waves by electrons and turbulent ion heating due to excitation of short wave ion Bernstein waves (IBW). In this report we present results of studies of plasma density fluctuations showing existence of a narrow bands near the frequencies of ? ? n?ci (n=1,2,3).

2006-01-01

441

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

Energy Technology Data Exchange (ETDEWEB)

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

1984-07-23

442

Electro-excitation of the 1/sup +/ state at 3,486 MeV in /sup 88/Sr  

Energy Technology Data Exchange (ETDEWEB)

The form factor for excitation of 1/sup +/ state at 3.846 MeV in /sup 88/Sr by inelastic electron scattering has been measured for q=0.22-2.57 fm/sup -1/. Both nuclear core polarization and ..delta..-hole polarization seem to be necessary to describe the observed reduction of the B(M1)-value and data at low q and the peculiar shape of the form factor at intermediate values of q.

1984-03-01

443

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

International Nuclear Information System (INIS)

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

444

Direct observation of intraionic and interconfigurational excitations in an intermediate-valence compound by Raman spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

Intraionic spin-orbit--split multiplet levels have been observed by electronic Raman scattering in the intermediate-valence compound EuPd/sub 2/Si/sub 2/. From the temperature dependence of the Raman peak positions and widths the interconfigurational excitation energy E/sub x/ and an upper limit of the interconfigurational mixing width T/sub f/, respectively, have been obtained. This is the first spectroscopic support for the underlying assumptions of the ionic interconfigurational fluctuation model that has been proposed to describe intermediate valence.

1985-01-21

445

Direct observation of intraionic and interconfigurational excitations in an intermediate-valence compound by Raman spectroscopy  

International Nuclear Information System (INIS)

Intraionic spin-orbit--split multiplet levels have been observed by electronic Raman scattering in the intermediate-valence compound EuPd_2Si_2. From the temperature dependence of the Raman peak positions and widths the interconfigurational excitation energy E/sub x/ and an upper limit of the interconfigurational mixing width T/sub f/, respectively, have been obtained. This is the first spectroscopic support for the underlying assumptions of the ionic interconfigurational fluctuation model that has been proposed to describe intermediate valence.

446

Decay of "1"7"7Ta composite system: comparison of excitation functions for the reaction residues occurring in "1"2C + "1"6"5Ho and "1"4N + "1"6"3Dy reactions  

International Nuclear Information System (INIS)

In the reactions induced by heavy ions, the study of breakup of heavy ions followed by the fusion of one of the fragments with the target has been of great interest. The present experiments has been performed with a view to compare the measured excitation functions for the same decay channels in "1"2C + "1"6"5Ho and "1"4N + "1"6"3Dy systems

2000-12-01

447

Collectivity at N=40 in neutron-rich "6"4Cr  

International Nuclear Information System (INIS)

"9Be-induced inelastic scattering of "6"2","6"4","6"6Fe and "6"0","6"2","6"4Cr was performed at intermediate beam energies. Excited states in "6"4Cr were measured for the first time. Energies and population patterns of excited states in these neutron-rich Fe and Cr nuclei are compared and interpreted in the framework of large-scale shell-model calculations in different model spaces. Evidence for increased collectivity and for distinct structural changes between the neighboring Fe and Cr isotopic chains near N=40 is presented.

2010-05-01

448

Coincidence measurements of M-shell excitation in slow Xe-Xe collisions  

Energy Technology Data Exchange (ETDEWEB)

Ion-photon and ion-Auger-electron coincidence measurements have been performed to study the impact parameter dependence of Xe M-shell excitation in 1.05 MeV Xe/sup 3 +/-Xe collisions. The experimental results are found to be consistent with the prediction of the molecular orbital model of atomic collisions. The average fluorescence yield for the Xe M shell is found to be strongly dependent on the impact parameter. This is ascribed to the production of highly charged Xe ions in close collisions.

1982-07-14

449

A traveling wave direct energy converter for a D-"3He fusion reactor  

International Nuclear Information System (INIS)

A concept of a traveling wave direct energy converter (TWDEC) is developed for 14.7-MeV fusion protons based on the principle of a backward wave oscillator. Separation of fusion protons from thermal ions is accomplished by using ExB ion drift. Energy conversion rate up to 0.87 is attained by applying three-stage modulation of the proton beam. A one-dimensional particle-circuit code is developed to examine self-excitation of the traveling wave and its stability under loading. Electrostatic wave with a fixed frequency is excited spontaneously, and stability of the wave is ensured under loading. (author).

450

A phenomenological Landau theory for electromagnons in cubic spinel multiferroic CoCr_2O_4  

International Nuclear Information System (INIS)

Non-anisotropic free energy is considered which under minimization yields two magnetic phases: a conical spin density wave and a low temperature conical cycloid. Using equations of motion, the excitation spectrum is studied. Knowing the nature of these excitations, the dielectric function as well as the fluctuation specific heat is computed and compared with the experimental spectrum. Due to the electromagnon going soft, the dielectric function (imaginary part) as well as the specific heat capacity show peaks at the temperature where ferroelectricity appears in the system.

2010-06-09

451

A measurement of the cross section for electron impact ionization of Ar"2"+, Kr"2"+ and Xe"2"+  

International Nuclear Information System (INIS)

The crossed electron-ion beams technique was used to measure absolute cross sections for single ionization of Ar"2"+, Kr"2"+ and Xe"2"+ ions at electron energies ranging from threshold to 2000 eV. In contrast to some previous measurements, the metastable contents of the ion beams were small even in the case of Xe"2"+. All measured cross section curves show significant contributions from excitation-autoionization and possibly direct ionization of inner-shell electrons. There is evidence for resonance-excitation-double-autoionization in the case of Xe"2"+. (author).

452

Investigations of electronic transitions and photodissociation of the bromine molecule  

Science.gov (United States)

The electronic transitions and photodissociation of the bromine molecule were studied in the visible-near UV continuum using dynamic simulation. The molar extinction coefficients in this study were obtained in numerical calculations. The quantum yields of the spin-orbit Br*(2 P 1/2) product at different photon frequencies were determined. Time-dependent density functional theory was used to analyze the highest five occupied and lowest five unoccupied Br2 orbitals. The transition to the 1? u state was found to be most probable in the visible-near UV absorption range.

2008-12-01

453

Enzymatic synthesis of N- and O-linked glycopeptides  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the study of kinetically controlled enzymatic coupling of N- and O-glycopeptide fragments using subtilisin BPN' and two of its variants developed for use in high concentrations of dimethylformamide and in aqueous solution, respectively. Glycosyl amino acids were exploited as the P[sub 1], P[sub 2], P[sub 3], P'[sub 1], P'[sub 2], or P'[sub 3] residue in the enzymatic coupling. Glycosyltransferase-mediated glycosylation of the glycopeptide fragments obtained prior to or after enzymatic peptide bond formation is demonstrated. 19 refs., 5 figs., 1 tab.

1993-07-14

454

(/sup 3/He,n) reaction in the Aapprox. =100 region  

Energy Technology Data Exchange (ETDEWEB)

The available experimental data on the (/sup 3/He,n) reaction between the ground states of even-even nuclei and lowest 1/2/sup -/ levels of odd-A nuclei in the Aapprox.=100 region are analyzed in a systematic way by the DWBA. The deduced relative intensities of these two-proton transfers, and their uncertainties, are compared to the predictions of various nuclear models. In particular, the influence of the finite dimension of the configuration space available to the transferred protons, and of the blocking effect of a 2p1/2/sup -/ proton, are examined. (orig.).

1986-03-01

455

Surface excitation correction of the inelastic mean free path in selected conducting polymers  

International Nuclear Information System (INIS)

In earlier works, the inelastic mean free path (IMFP) of electrons was determined by elastic peak electron spectroscopy (EPES) using Ni and Ag reference standard samples, but fully neglecting surface excitation. Surface excitation that is characterized by the surface excitation parameter (SEP), and may affect considerably the elastic peak for the sample and the reference material. The SEP parameters of selected conducting polymers (polythiophenes, polyaniline and polyethylene) were determined by EPES using Si and Ge reference samples. Experiments were made with a hemispherical analyzer of energy resolution 100-200 meV in the E = 0.2-2.0 keV energy range. The composition of the sample surfaces was determined by in situ XPS, their surface roughness by AFM. The experimental SEP parameter data of eight polymer samples were determined by our new procedure, using the formulae of Chen and Werner et al. in the E = 0.2-2.0 keV ...

2006-05-15

456

3D time-of-flight MR angiography of the intracranial vessels: optimization of the technique with water excitation, parallel acquisition, eight-channel phased-array head coil and low-dose contrast administration  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study is three folds: to compare the eight-channel phased-array and standard circularly polarized (CP) head coils in visualiazation of the intracranial vessels, to compare the three-dimentional (3D) time-of-flight (TOF) MR angiography (MRA) techniques, and to define the effects of parallel imaging in 3D TOF MRA. Fifteen healthy volunteers underwent 3D TOF MRA of the intracranial vessels using eight-channel phased-array and CP standard head coils. The following MRA techniques were obtained on each volunteer: (1) conventional 3D TOF MRA with magnetization transfer; (2) 3D TOF MRA with water excitation for background suppression; and (3) low-dose (0.5 ml) gadolinium-enhanced 3D TOF MRA with water excitation. Results are demonstrating that water excitation is a valuable background suppression technique, especially when applied with an eight-channel phased-array head coil. For central and proximal portions of the ...

2004-11-01

457

Ab initio calculations of the electronic structure of the silver palladium oxide Ag_2PdO_2  

International Nuclear Information System (INIS)

Ab initio calculations of the electronic structure were performed for the silver palladium oxide, Ag_2PdO_2, by the full potential mixed linearized augmented plane wave and augmented plane wave plus local orbitals method (mixed LAPW/APW+lo) within the density functional theory and using the generalized gradient approximation (GGA96, Phys. Rev. Lett. 77 (1996) 3865) for the exchange-correlation potential. The lattice parameters were calculated from the ground-state total energy versus volume curve, and are in good agreement with the available experimental results. Our calculations of band structure predicted that the compound Ag_2PdO_2 has indirect band gap, and the Pd 4d states strongly hybridize with the O 2p states all over the valence bands and conduction bands. The valence bands are composed mainly of Ag, Pd 4d states and O 2p states, while the conduction bands consist mainly of the Pd 4d states and ...

2003-09-01

458

Low power cross-flow atmospheric pressure Ar + He plasma jet  

International Nuclear Information System (INIS)

A cross-flow atmospheric plasma jet with distilled water or analyte solution nebulization has been investigated. The plasma gas flows perpendicularly to the RF powered electrode (11.21 MHz) and a grounded electrode was added for plasma stabilization. The working parameters of the plasma generator can be controlled in order to maximize either the plasma power (75 W) or the voltage on the RF powered electrode (plasma power, 40 W). The plasma gas, pure argon (0.4 l min-1) or a mixture of argon (0.3-0.4 l min-1) and helium (0-0.2 l min-1), was also used for liquid nebulization. Optical emission of the plasma, collected in the normal viewing mode, was used for plasma diagnostics and for evaluating its excitation capabilities. The influence of helium content in the mixed-gas plasma on the plasma characteristics and on the emission axial profiles of the plasma gas constituents and of the analytes originate from the wet aerosol was studied. The addition of helium to the ...

2010-04-01

459

Decay of {sup 177}T{sub a} composite nucleus. Comparison of excitation functions for the reaction residues occurring in {sup 12}C + {sup 165}H{sub 0} and {sup 14}N + {sup 163}D{sub y} reactions  

Energy Technology Data Exchange (ETDEWEB)

The experimental has been performed with a view to studying complete and incomplete fusion in {sup 14}N + {sup 163}D{sub y} system below 7 MeV/nucleon. The excitation functions for several reactions have been measured using the activation technique and compared with the theoretical predictions based on statistical models. The codes ALICE-91 and CASCADE used earlier for the analysis of excitation functions in case of {sup 12}C + {sup 165}H{sub 0} system have been used here also with the same set of input parameters. It has been observed that the theoretical calculations do not match with the experimental excitation functions well but the overall shape of the excitation function is reproduced satisfactorily. The composite nucleus ({sup 177}T{sub a}) formed in this ({sup 14}N + {sup 163}D{sub y}) case is the same as the one formed in {sup 12}C + {sup 165}H{sub 0} system studied earlier. Measured ...

2002-10-01

460

Infrared stimulated luminescence and phosphorescence spectra of irradiated feldspars  

International Nuclear Information System (INIS)

A new high-sensitivity wide-bandwidth 1.25-5.5 eV (225-1000 nm) spectrometer has been constructed to measure luminescence emission spectra of minerals that are of interest for optical dating. Spectra of emission resulting from 1.43 eV (IR) excitation after #gamma#-irradiation are reported for 13 cut rock feldspars and 20 feldspar separates. Also reported are phosphorescence spectra following #gamma#-irradiation, and after 1.4 eV excitation. The main differences between the infrared stimulated luminescence spectra and the phosphorescence is the almost complete absence of the violet, 3.1 eV, and yellow-green, 2.2 eV, bands in the phosphorescence, and the presence of a green emission band centred at 2.7 eV in the phosphorescence following #gamma#-irradiation (but absent in the phosphorescence following 1.4 eV excitation). The red, 1.7 eV, band is present in all the phosphorescence spectra but is not always seen during 1.4 eV ...

2003-11-26

461

Phase 2 Final Report. IAEA Safeguards: Implementation blueprint of commercial satellite imagery  

International Nuclear Information System (INIS)

This document - IAEA Safeguards: Implementation Blueprint of Commercial Satellite Imagery - constitutes the second report from SSC Satellitbild giving a structured view and solid guidelines on how to proceed with a conceivable implementation of satellite imagery to support Safeguards activities of the Agency. This Phase 2 report presents a large number of concrete recommendations regarding suggested management issues, work organisation, imagery purchasing and team building. The study has also resulted in several lists of actions and preliminary project plans with GANT schedules concerning training, hardware and software, as well as for the initial pilot studies. In both the Phase 1 and Phase 2 studies it is confirmed that the proposed concept of a relatively small Imagery Unit using high-resolution data will be a sound and feasible undertaking. Such a unit capable of performing advanced image processing as a tool for various safeguard tasks ...

1989-08-01

462

THE CHEMICAL EVOLUTION OF THE URSA MINOR DWARF SPHEROIDAL GALAXY  

International Nuclear Information System (INIS)

We present an abundance analysis based on high-resolution spectra of 10 stars selected to span the full range in metallicity in the Ursa Minor (UMi) dwarf spheroidal (dSph) galaxy. We find that [Fe/H] for the sample stars ranges from -1.35 to -3.10 dex. Combining our sample with previously published work for a total of 16 luminous UMi giants, we establish the trends of abundance ratios [X/Fe] as functions of [Fe/H] for 15 elements. In key cases, particularly for the #alpha#-elements, these trends resemble those for stars in the outer part of the Galactic halo, especially at the lowest metallicities probed. The neutron-capture elements show an r-process distribution over the full range of Fe metallicity reached in this dSph galaxy. This suggests that the duration of star formation in the UMi dSph was shorter than in other dSph galaxies. The derived ages for a larger sample of UMi stars with more uncertain metallicities also suggest a population dominated by uniformly old (#approx#13 ...

2010-08-10

463

Wetlands mapping with spot multispectral scanner data  

Energy Technology Data Exchange (ETDEWEB)

Government facilities such as the US Department of Energy's Savannah River Plant (SRP) near Aiken, South Carolina, often use remote sensing data to assist in environmental management. Airborne multispectral scanner (MSS) data have been acquired at SRP since 1981. Various types of remote sensing data have been used to map and characterize wetlands. Regional Landsat MSS and TM satellite data have been used for wetlands mapping by various government agencies and private organizations. Furthermore, SPOT MSS data are becoming available and provide opportunities for increased spacial resolution and temporal coverage for wetlands mapping. This paper summarizes the initial results from using five dates of SPOT MSS data from April through October, 1987, as a means to monitor seasonal wetland changes in freshwater wetlands of the SRP. 11 refs., 4 figs.

1989-01-01

464

Viewpoint: Space System Negation in the Context of Space Policy and Law  

British Library Electronic Table of Contents (United Kingdom)

For 21st century warfare, space is the unquestioned new high ground for military operations. The United States (U.S.) has relied on satellites for significant support to military operations and activities since Desert Storm in 1991. Indeed, the U.S. enjoys an asymmetric advantage in modern warfare utilizing our space capabilities. States with interests hostile to the U.S. believe that the significant dependence on space assets by the U.S. military could become its "Achilles heel" in future combat operations. What are the legal and policy bases for the U.S. to respond to threats to space systems that provide support to our military forces? Should the U.S. rely on space arms control initiatives to ensure security in space? This Viewpoint analyzes the international space law regime and U.S. N...

2007-01-01

465

VLF wave stimulation by pulsed electron beams injected from the space shuttle  

International Nuclear Information System (INIS)

Among the investigations conducted on the space shuttle flight STS 3 March 1982 was an experiment in which a 1-keV, 100-mA electron gun was pulsed at 3.25 and 4.87 kHz. The resultant waves were measured with a broadband plasma wave receiver. At the time of flight the experimental setup was unique in that the electron beam was square wave modulated and that the shuttle offered relatively long times for in situ measurements of the ionospheric plasma response to the VLF pulsing sequences. In addition to electromagnetic response at the pulsing frequencies the waves exhibited various spectral harmonics as well as the unexpected occurrence of satellite lines around those harmonics. Both phenomena occurred with a variety of different characteristics for different pulsing sequences.

466

Upper Limits from HESS Observations of AGN in 2005-2007  

CERN Document Server

Very high energy (VHE; >100 GeV) observations of a sample of selected active galactic nuclei (AGN) were performed between January 2005 and April 2007 with the High Energy Stereoscopic System (HESS), an array of imaging atmospheric-Cherenkov telescopes. Significant detections are reported elsewhere for many of these objects. Here, integral flux upper limits for twelve candidate very high energy (VHE; >100 GeV) gamma-ray emitters are presented. In addition, results from HESS observations of four known VHE-bright AGN are given although no significant signal is measured. For three of these AGN (1ES 1101-232, 1ES 1218+304, and Mkn 501) simultaneous data were taken with the Suzaku X-ray satellite.

2007-01-01

467

Three-dimensional elastic lidar winds  

Energy Technology Data Exchange (ETDEWEB)

Maximum cross-correlation techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum cross-correlation technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a function of range and altitude from incoherent elastic backscatter lidar data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three- dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain following winds in the Rio Grande valley.

1996-07-01

468

Thermal impact analysis of discharge of circulating cooling water at Daya Bay Nuclear Power Station (GNPS) and Ling'ao Nuclear Power Station (LNPS)  

International Nuclear Information System (INIS)

The circulating cooling water flowrate of GNPS and LNPS is totally about 190 m"3/s. Both stations are located on the western coast of semi-closed Daya Bay. A lot of studies concerning thermal impact of GNPS and LNPS have been carried out since 1987, including mathematical model, physical model, on-site survey and satellite remote sensing, etc. This paper describes the hydrological features of Daya Bay and discharge characteristics of circulating water of GNPS and LNPS, estimates the actual thermal impact of GNPS and LNPS, and indicates that it is advantageous for the dilution of circulating water while the two discharge channels of GNPS and LNPS are combined together towards east

2004-05-01

469

The impact of solar flares and magnetic storms on humans  

International Nuclear Information System (INIS)

Three classes of solar emanations, namely, photon radiation from solar flares, solar energetic particles, and inhomogeneities in the solar wind that drive magnetic storms, are examined, and their effects on humans and technological systems are discussed. Solar flares may disrupt radio communications in the HF and VLF ranges. Energetic particles pose a special hazard at low-earth orbit and above, where they can penetrate barriers such as spacesuits and aluminum and destroy cells and solid state electronics. Energetic solar particles also influence terrestrial radio waves propagating through polar regions. Magnetic storms may disturb the operation of navigation instruments, power lines and pipelines, and satellites; they give rise to ionospheric storms which affect radio communication at all latitudes. There is also a growing body of evidence that changes in the geomagnetic field affect biological systems. 3 refs.

470

The Planck-ATCA Coeval Observations project: the faint sample  

British Library Electronic Table of Contents (United Kingdom)

Abstract The Planck-ATCA Coeval Observations (PACO) project collected data between 4.5 and 40 GHz for 482 sources selected within the Australia Telescope 20 GHz (AT20G) catalogue and observed with the Australia Telescope Compact Array. Observations were done almost simultaneously with the-Planck-satellite, in the period between 2009 July and 2010 August. In this paper, we present and discuss the data for the complete sample of 159 sources with-SAT20G > 200-mJy in the South Ecliptic Pole region. The Planck Early Release Compact Source Catalogue (ERCSC) contains 57 of our sources. A comparison between the PACO catalogue and the ERCSC confirms that the reliability of the latter is better than 95-per cent. The missing ERCSC sources are typically associated with the Large Magellanic Cloud, the ...

2011-01-01

471

The Assisi landslide monitoring: a multi-year activity based on geomatic techniques  

British Library Electronic Table of Contents (United Kingdom)

A wide area of the Assisi town, in Umbria (central Italy), is interested since its first edification (1950?1960) by an extensive landslide. The rate of motion is very slow (around 1?cm/year), but the deformations accumulated for almost 60?years have produced considerable damage to many private and public buildings, including the civic hospital and an important Franciscan monastery. The University of Perugia established in 1995 a geodetic monitoring network over the Assisi landslide, connecting a number of control points inside the moving area to an external reference network with markers placed on stable geological formations. The monitoring has been based since the beginning on GPS satellite positioning with static observations, aiming to obtain a three-dimensional accuracy of about 1?cm ...

2011-01-01

472

TOA/FOA geolocation error analysis.  

Energy Technology Data Exchange (ETDEWEB)

This paper describes how confidence intervals can be calculated for radiofrequency emitter position estimates based on time-of-arrival and frequency-of-arrival measurements taken at several satellites. These confidence intervals take the form of 50th and 95th percentile circles and ellipses to convey horizontal error and linear intervals to give vertical error. We consider both cases where an assumed altitude is and is not used. Analysis of velocity errors is also considered. We derive confidence intervals for horizontal velocity magnitude and direction including the case where the emitter velocity is assumed to be purely horizontal, i.e., parallel to the ellipsoid. Additionally, we derive an algorithm that we use to combine multiple position fixes to reduce location error. The algorithm uses all available data, after more than one location estimate for an emitter has been made, in a mathematically optimal way.

2008-08-01

473

Simulation study of the influence of the ionospheric layer height in the thin layer ionospheric model  

British Library Electronic Table of Contents (United Kingdom)

This work aims to contribute to the understanding of the influence of the ionospheric layer height (ILH) on the thin layer ionospheric model (TLIM) used to retrieve ionospheric information from the GNSS observations. Particular attention is paid to the errors caused on the estimation of the vertical total electron content (vTEC) and the GNSS satellites and receivers inter-frequency biases (IFB), by the use of an inappropriate ILH. The work relies upon numerical simulations performed with an empirical model of the Earth?s ionosphere: the model is used to create realistic but controlled ionospheric scenarios and the errors are evaluated after recovering those scenarios with the TLIM. The error assessment is performed in the Central and the northern part of the South American continents, a re...

2011-01-01

474

Satellite power system (SPS) concept definition study (Exhibit D). Volume 2: systems/subsystems analyses. Final report  

Energy Technology Data Exchange (ETDEWEB)

Modifications to the reference concept were studied and the best approaches defined. The impact of the high efficiency multibandgap solar array on the reference concept design is considered. System trade studies for several solid state concepts, including the sandwich concept and a separate antenna/solar concept, are described. Two solid state concepts were selected and a design definition is presented for each. Magnetrons as an alternative to the reference klystrons for dc/rf conversion are evaluated. System definitions are presented for the preferred klystron and solid state concepts. Supporting systems are analyzed, with major analysis in the microwave, structures, and power distribution areas. Results of studies for thermal control, attitude control, stationkeeping, and details of a multibandgap solar cell study are included. Advanced laser concepts and the meteorological effects of a laser beam power transmission concept are considered.

1981-01-01

475

Rondonia Deforestation (WMS)  

Science.gov (United States)

Throughout much of the 1980s, deforestation in Brazil eliminated more than 15,000 square kilometers (9000 square miles) of forest per year. Data gathered by several satellites in the Landsat series of spacecraft shows enormous tracts of forest disappearing in Rondonia, Brazil from 1975 through 2001. The human phenomenon of deforestation starts, especially in the dense tropical forests of Brazil, when systematic cutting of a road opens new territory to potential deforestation by penetrating into new areas. Clearing of vegetation along the sides of those roads then tends to fan out to create a pattern akin to a fish skeleton. As new paths appear in the woods, more areas become vulnerable. Finally, the spaces between the skeletal bones fall to defoliation.

2005-02-17

476

Remote sensing; Fernerkundung  

Energy Technology Data Exchange (ETDEWEB)

The potential of different multitemporal and multispectral airborne and spaceborne remote sensing methods for assessment and monitoring of the lignite open-cast mining areas are discussed in this chapter. Emphasis is placed on the successful use of different remote sensing data in variable vegetation structures for dumped sediments with different mineralogical and geochemical properties and for hydrochemical properties of the residual lakes. Multiple remote sensing data are a cost and time efficient tool for the assessment of environmental impacts, supervising of reclamation activities as well as for long term monitoring of the mining area. The airborne data are well suited for large scale detailed research and mapping in smaller sites and the satellite data for the overview scale 1:50 000. An integrated remote sensing-GIS-system including all field and lab data, DTM and other graphical data, improve the results of the remote sensing data classification for the ...

2001-07-01

477

Remote sensing analysis of rainstorm effects on sediment concentrations in Apalachicola Bay, USA  

British Library Electronic Table of Contents (United Kingdom)

Remote sensing of total suspended solids (TSS) by satellite techniques in estuaries and bays plays an important role in monitoring water quality over a large area. It is valuable to the management of coastal water environment and ecosystems. In this study, remote sensing mapping of TSS was conducted to investigate the effects of rainstorm events on Apalachicola Bay. A rainstorm event (October 7-8, 2008) was selected for a period when wind speeds were weak and the river inflow was almost steady. TSS mapping of MODIS images before and after the rainstorm event showed substantial increase of TSS induced by the rainstorm. Using an image during low river discharge before the rainstorm as a reference, TSS distribution was mapped by an improved regression model using MODIS image after a rainstorm...

2011-01-01

478

Performance of a low cost solar paraboloidal dish steam generating system  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the design, development and performance characteristics of a low cost solar steam generating system which incorporates recent design and materials innovations of parabolic dish technology. The concentrator is a deep dish of rather imperfect optics, made of silvered polymer reflectors fitted in the aluminum frame of a satellite communication dish. Conventional cavity receivers tend to be inadequate for this concentrator. Semi-cavity and modified cavity receivers, thermally optimised, with the fuzzy focal image have, therefore, been investigated. Preliminary field measurements and cost, as well as performance analyses of the system, indicate a solar to steam conversion efficiency of 70-80% at 450{sup o}C and a collector system cost of Rs 8000-9000/m{sup 2} (1 US dollar = Rs, 40.0). (author)

2000-05-01

479

Morphological characteristics and medium-term evolution of the beaches between Ceuta and Cabo Negro (Morocco)  

British Library Electronic Table of Contents (United Kingdom)

This work presents the results of a combined study on the beach morphology and the evolution at short- and medium-term of the littoral between Ceuta and Cabo Negro (Morocco). It is an interesting sector showing a great increase of human occupation and coastal structures. The monitoring program allowed for the reconstruction of the beach morphological behavior and the seasonal changes. The studied beaches presented reflective profiles recording little seasonality, with the most notable morphological changes being strictly related to storms. Surf Similarity and Surf Scaling parameters highlighted the existence of intermediate and reflective beach states, characterized by plunging breakers. Aerial photographs and a satellite image have been geo-referenced and elaborated with GIS tools to reco...

2007-01-01

480

Modeling and numerical simulation of linear and nonlinear spacecraft attitude dynamics and gravity gradient moments: A comparative study  

British Library Electronic Table of Contents (United Kingdom)

In this paper linear and nonlinear models of spacecraft attitude dynamics equations and gravity gradient moments are investigated. In addition, effects of gravity gradient moments on attitude dynamics of the satellite are studied. The purpose of this paper is to present a comparison between nonlinear and linear models of spacecraft attitude dynamics and gravity gradient moments in order to determine divergence of linear approximation from the nonlinear model. Simulation results indicate that designer of spacecraft attitude control subsystem should be meticulous in applying linear approximation of equations especially in low earth orbits. Consequently, finding an upper bound for small angle to keep the linear model valid and precise enough would be a vital part of using linear approximation...

2012-01-01

481

Model of coral population response to accelerated bleaching and mass mortality in a changing climate  

British Library Electronic Table of Contents (United Kingdom)

We model coral community response to bleaching and mass mortality events which are predicted to increase in frequency with climate change. The model was parameterized for the Arabian/Persian Gulf, but is generally applicable. We assume three species groups (Acropora, faviids, and Porites) in two life-stages each where the juveniles are in competition but the adults can enter a size-refuge in which they cannot be competitively displaced. An aggressive group (Acropora species) dominates at equilibrium, which is not reached due to mass mortality events that primarily disadvantage this group (compensatory mortality, >90% versus 25% in faviids and Porites) roughly every 15 years. Population parameters (N individuals, carrying capacity) were calculated from satellite imagery and in situ transect...

2009-01-01

482

Metazoa parasites of the invasive round goby Apollonia melanostoma (Neogobius melanostomus) (Pallas) (Gobiidae: Osteichthyes) in the Gulf of Gda?sk, Baltic Sea, Poland: a comparison with the Black Sea  

British Library Electronic Table of Contents (United Kingdom)

The known metazoa parasite fauna of the invasive round goby Apollonia melanostoma (formerly Neogobius melanostomus) consists of 12 species. The core of the parasite fauna comprises two species: Cryptocotyle concavum and Diplostomum spathaceum; secondary species are absent; satellite species include Cercariae gen. sp. and Ergasilus sieboldi; rare species are Acanthocephalus lucii, Anguillicola crassus, Bothriocephalus sp., Dichelyne minutus, Hysterothylacium aduncum, Pomphorhynchus laevis, Piscicola geometra, and Tylodelphys clavata. Fifty percent of metazoa parasites that occurred in the invasive round goby in the Gulf of Gda?sk (an invasion that was first detected in 1990) are also typically found in the native Gulf of Gda?sk gobiids. The round goby hosts common fish parasite species: C. ...

2007-01-01

483

Hazardous-waste disposal and the clinical laboratory. Final report, May-December 1989  

Energy Technology Data Exchange (ETDEWEB)

Negligent hazardous waste management has resulted in real threats to public health. The Federal Government has responded to the situation with laws and regulations aimed at the producers of hazardous waste, including clinical laboratories. The Resources Conservation and Recovery Act (RCRA) imposes controls on hazardous waste management through the Code of Federal Regulations (CFR). The Environmental Protection Agency (EPA) and the Department of Transportation (DOT) regulate these activities through 40 CFR and 49 CFR. Most clinical laboratories can operate satellite accumulation points and accumulate, store, transport, and dispose of waste in accordance with EPA and DOT regulations. Regulations pertaining to infectious waste, sure to affect many clinical laboratories, are being developed now by he EPA. The cradle to grave tracking system mandated by the Federal Government can be supplemented by state and local authorities and poses a significant regulatory challenge ...

1990-01-01

484

Geospatial tools for assessing land degradation in Budgam district, Kashmir Himalaya, India  

British Library Electronic Table of Contents (United Kingdom)

Land degradation reduces the ability of the land to perform many biophysical and chemical functions. The main aim of this study was to determine the status of land degradation in the Budgam area of Kashmir Himalaya using remote sensing and geographic information system. The satellite data together with other geospatial datasets were used to quantify different categories of land degradation. The results were validated in the field and an accuracy of 85% was observed. Land use/land cover of the study area was determined in order to know the effect of land use on the rate of land degradation. Normalized differential vegetation index (NDVI) and slope of the area were determined using LANDSAT-enhanced thematic mapper plus (ETM+) data, advanced space borne thermal emission and reflection radiome...

2011-01-01

485

GPM on The High Capapcity Centrifuge  

National Aeronautics and Space Administration (NASA)

GPM moves from the clean room to the test chamber on a dolly without wheels. Compressed air is pumped out under airpads that float the Spacecraft on a bed of air. nThe wind generated when the centrifuge moves at its maximum speed are more than 200 mph - that's tornado speed. But since they move with the centrifuge the satellites tested only feel 20 mph winds. nLeaning outward at 45 degrees for one test orientation, GPM comes within 28 inches of the wall. When lifted onto the platform it cleared the ceiling by only five inches. nNatural audio only. nVideo Credit: Brooke Harris n

2011-10-19

486

Five Special Types of Orbits Around Mars  

CERN Document Server

The abstract is additional with repect to the paper published in JGCD. Ordinary Earth satellites are usually placed into five categories of special orbits: sun-synchronous orbits, orbits at the critical inclination, frozen orbits, repeating ground track orbits, and geostationary orbits. This paper investigates their counterparts around Mars and examines the basic nature of these orbits, which are of special interest for missions conducted around Mars, including Mars reconnaissance. Mars' gravity field is much more complicated, with relatively smaller J2, compared to Earth's, which makes the behaviors of these Martian orbits different from those of Earth. Analytical formulations and numerical simulations are used to analyze these Martian orbits and compare them with their Earth counterparts. First, mean element theory is employed to describe variations of orbital elements and give the constraint conditions for achieving these special orbits. Then, numerical ...

2011-01-01

487

FUV and X-ray absorption in the Warm-Hot Intergalactic Medium  

CERN Document Server

The Warm-Hot Intergalactic Medium (WHIM) arises from shock-heated gas collapsing in large-scale filaments and probably harbours a substantial fraction of the baryons in the local Universe. Absorption-line measurements in the ultraviolet (UV) and in the X-ray band currently represent the best method to study the WHIM at low redshifts. We here describe the physical properties of the WHIM and the concepts behind WHIM absorption line measurements of H I and high ions such as O VI, O VII, and O VIII in the far-ultraviolet and X-ray band. We review results of recent WHIM absorption line studies carried out with UV and X-ray satellites such as FUSE, HST, Chandra, and XMM-Newton and discuss their implications for our knowledge of the WHIM.

2008-01-01

488

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

489

Energy balance of the area influenced by brown coal mining in three phases  

Science.gov (United States)

The change in the energy flow on land used for brown coal mining is examined. Terrain mapping was used to obtain land use data for a 14 km{sup 2} mining area and its surroundings. The focus is on the proportion of incident solar energy that is changed to latent heat during evapotranspiration. Each land use unit was assigned an average value for evapotranspiration for the growing season. Satellite data of surface temperature and surface wetness values show incident radiation converted to heat. Relationships between evapotranspiration and surface temperature and between wetness index and evapotranspiration were verified. The results confirm the hypothesis that changes in land use can have a significant effect on total average evapotranspiration. 18 refs., 5 figs., 3 tabs.

2005-07-01

490

Effects of wildfires on environmental variability: a comparative analysis using different spectral indices, patch metrics and thematic resolutions  

British Library Electronic Table of Contents (United Kingdom)

Knowledge on environmental variability and how it is affected by disturbances is crucial for understanding patterns of biodiversity and determining adequate conservation strategies. The aim of this study is to assess environmental variability in patches undergoing post-fire vegetation recovery, identifying trends of change and their relevant drivers. We particularly evaluate: the value of three spectral indices derived from Landsat satellite data [Normalized Burn Ratio (NBR), Normalized Difference Vegetation Index (NDVI) and Wetness Component of the Tasseled Cap Transformation (TCW)] for describing secondary succession; the effectiveness of three metrics (diversity, evenness and richness) as indicators of patch variability; and how thematic resolution can affect the perception of environme...

2010-01-01

491

Discovery of a Red Giant with Solar-like Oscillations in an Eclipsing Binary System from Kepler Space-based Photometry  

DEFF Research Database (Denmark)

Oscillating stars in binary systems are among the most interesting stellar laboratories, as these can provide information on the stellar parameters and stellar internal structures. Here we present a red giant with solar-like oscillations in an eclipsing binary observed with the NASA Kepler satellite. We compute stellar parameters of the red giant from spectra and the asteroseismic mass and radius from the oscillations. Although only one eclipse has been observed so far, we can already determine that the secondary is a main-sequence F star in an eccentric orbit with a semi-major axis larger than 0.5 AU and orbital period longer than 75 days.

2010-01-01

492

Crystal structure of the human centromeric nucleosome containing CENP-A  

British Library Electronic Table of Contents (United Kingdom)

In eukaryotes, accurate chromosome segregation during mitosis and meiosis is coordinated by kinetochores, which are unique chromosomal sites for microtubule attachment. Centromeres specify the kinetochore formation sites on individual chromosomes, and are epigenetically marked by the assembly of nucleosomes containing the centromere-specific histone H3 variant, CENP-A. Although the underlying mechanism is unclear, centromere inheritance is probably dictated by the architecture of the centromeric nucleosome. Here we report the crystal structure of the human centromeric nucleosome containing CENP-A and its cognate ?-satellite DNA derivative (147 base pairs). In the human CENP-A nucleosome, the DNA is wrapped around the histone octamer, consisting of two each of histones H2A, H2B, H4 and CENP...

2011-01-01

493

Cosmological model selection  

CERN Document Server

Model selection aims to determine which theoretical models are most plausible given some data, without necessarily asking about the preferred values of the model parameters. A common model selection question is to ask when new data require introduction of an additional parameter, describing a newly-discovered physical effect. We review several model selection statistics, and then focus on use of the Bayesian evidence, which implements the usual Bayesian analysis framework at the level of models rather than parameters. We describe our CosmoNest code, which is the first computationally-efficient implementation of Bayesian model selection in a cosmological context. We apply it to recent WMAP satellite data, examining the need for a perturbation spectral index differing from the scale-invariant (Harrison-Zel'dovich) case.

2006-01-01

494

Analysis of Ground Deformation Detected Using the SBAS-DInSAR Technique in Umbria, Central Italy  

British Library Electronic Table of Contents (United Kingdom)

Ground deformation affecting the Umbria region (central Italy) in the 9-year period from 1992 to 2000 was investigated through multi-temporal Differential Synthetic Aperture Radar Interferometry (DInSAR). For the purpose, the Small BAseline Subset (SBAS) technique was adopted, which allows studying the temporal evolution of the detected deformation at two spatial scales: a low-resolution (regional) scale, and a full-resolution (local) scale. For the analysis, SAR data acquired by the European Remote Sensing (ERS-1/2) satellites along ascending and descending orbits were used. The detected deformation was analysed to investigate its relevance to geophysical, geomorphologic, and human-induced processes that may result in hazardous conditions to the population of Umbria. Low-resolution deform...

2009-01-01

495

A combined interpretation of cosmic ray and antiproton high energy measurements  

Energy Technology Data Exchange (ETDEWEB)

In the last months several ballon and satellite experiments improved significantly our knowledge of cosmic ray (CR) spectra at high energy. In particular CREAM allowed to measure B/C, C/O and N/O ratios up to 1 TeV/n and PAMELA the anti p/p ratio up to 100 GeV with unprecedented accuracy. These measurements offer a valuable probe of CR propagation properties. We performed a statistical analysis to test the compatibility of these results, as well as other most significant experimental data, with the predictions of a new numerical CR diffusion package (DRAGON). We found that above 1 GeV/n all data are consistent with a plain diffusion scenario and point to well defined ranges for the normalization and energy dependence of the diffusion coefficient. (orig.)

2009-09-15

496

Yield and excitation function measurements of some nuclear reactions on natural thallium induced by protons leading to the production of medical radioisotopes {sup 201}Tl and {sup 203}Pb  

Energy Technology Data Exchange (ETDEWEB)

Excitation functions for {sup 201}Pb, {sup 202m}Pb, {sup 203}Pb and {sup 204m}Pb radionuclides which are formed via proton induced reactions with natural thallium target have been measured from their respective threshold (E{sub thr}) to 27.5 MeV using activation technique. Natural copper foils were used to monitor the cyclotron beam. The integral yields (MBq/{mu}A h) of the produced radionuclides were calculated from the measured excitation functions. The optimum proton energy range for the production of {sup 203}Pb with low amount of impurities is (16-10 MeV) after 5 h of EOB. The experimental cross-sections for {sup nat}Tl(p,xn) reactions were compared with the cross-sections recommended by the IAEA and with earlier published data when it was possible. (orig.)

2007-07-01

497

Search for excited and exotic muons in the mu gamma decay channel in p anti-p collisions at s**(1/2) = 1.96-TeV  

Energy Technology Data Exchange (ETDEWEB)

The authors present a search for excited and exotic muon states {mu}*, conducted using an integrated luminosity of 371 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV at the Tevatron with the CDF II detector. They search for associated production of {mu}{mu}* followed by the decay {mu}* {yields} {mu}{gamma}, resulting in the {mu}{mu}{gamma} final state. They compare the data to model predictions as a function of the mass of the excited muon M{sub {mu}*}, the compositeness energy scale {Lambda}, and the gauge coupling factor f. No signal above the standard model expectation is observed in the {mu}{gamma} mass spectrum. In the contact interaction model, they exclude 107 < M{sub {mu}*} < 853 GeV/c{sup 2} for {Lambda} = M{sub {mu}*}; in the gauge-mediated model, they exclude 100 < M{sub {mu}*} < 410 GeV/c{sup 2} for f/{Lambda} = 10{sup -2} GeV{sup -1}. These 95% confidence level exclusions ...

2006-06-01

498

New high-spin isomer and quasiparticle-vibration coupling in "1"8"7Ir  

International Nuclear Information System (INIS)

The high-spin structure of the Z=77 nucleus "1"8"7Ir has been studied using the fusion-evaporation reaction "1"8"6W("7Li6n) at a beam energy of 59 MeV. The excitation scheme of this nucleus has been extended by more than 110 new states, including extensions of all previously established rotational bands. The band crossing region of the h_9_/_2 negative-parity yrast band has been revised and new intrinsic high-K states have been identified. In particular, a 29/2"- isomeric state [T_1_/_2=1.8(5)#mu#s] at an excitation energy of 2487 keV has been observed for the first time, and on top of it, a rich level scheme reaching up to spin (59/2"-) and excitation energies around 7 MeV has been established.

2010-05-01

499

Coulomb gauge QCD as a tool for the excited spectrum  

CERN Document Server

A distinct feature of Coulomb gauge QCD is that it can be formulated in terms of physical, transverse gluons and quarks alone. The state-counting is then transparent, and the gauge is suited for studies of the excited spectrum. Leaving aside exotic spectroscopy, which has been the subject of other publications, in this note I call attention on two recent applications. One is that the running quark mass in the mid-infrared can be probed from excited baryons thanks to parity doubling, a consequence of insensitivity to chiral symmetry breaking. Fast quarks are asymptotically free and behave as massless, so hadrons containing fast quarks decouple from the condensate. Their (power-law) rate of decoupling reflects on the rate of decreasing parity splittings, which can be measured. The second is that, in analogy with the Franck-Condon principle of molecular physics, the velocity distribution of the heavy quarks inside a heavy hadron can be mapped out ...

2010-01-01

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Action Potentials in a Giant Algal Cell: A Comparative Approach to Mechanisms and Evolution of Excitability  

Science.gov (United States)

The giant alga Chara corallina generates action potentials (APs) in response to mechanical stimulation, injury, or direct electrical stimulation. Students examine the waveform characteristics of these APs using standard intracellular recording techniques. Intracellular recording is easier than with neurons because of the large size of the Chara cell. Students observe very negative resting potentials (up to -250 mV), large AP amplitudes with depolarizing peaks approaching 0 mV, AP durations of seconds, and refractory periods up to several minutes. Students calculate Nernst potentials for the ions distributed across the Chara cell membrane to hypothesize the ions responsible for the resting potential and for the depolarizing phase of the AP. These calculations suggest that K+ is responsible for the resting potential and that Ca2+ influx and Ca2+-activated Cl- efflux are responsible for depolarizing phases of the AP, which they are. Comparison of the Chara AP characteristics with animal ...

2008-06-11