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1

The study on fishing ground of neon flying squid, Ommastrephes bartrami, and ocean environment based on remote sensing data in the Northwest Pacific Ocean  

NASA Astrophysics Data System (ADS)

The relationships between the neon flying squid, Ommastrephes bartrami, and the relative ocean environmental factors are analyzed. The environmental factors collected are sea surface temperature (SST), chlorophyll concentration (Chl- a) and sea surface height (SSH) from NASA, as well as the yields of neon flying squid in the North Pacific Ocean. The results show that the favorable temperature for neon flying squid living is 10°C-22°C and the favorite temperature is between 15°C-17°C. The Chl- a concentration is 0.1-0.6 mg/m3. When Chl- a concentration changes to 0.12-0.14 mg/m3, the probability of forming fishing ground becomes very high. In most fishing grounds, the SSH is higher than the mean SSH. The generalized additive model (GAM) was applied to analyze the correlations between neon flying squid and ocean environmental factors. Every year, squids migrate northward from June to August and return southward during October-November, and the characteristics of the both migrations are very different. When squids migrate to the north, most relationships between the yields and SST are positive. The relationships are negative when squids move to southward. The relationships between the yields and Chl- a concentrations are negative from June to October, and insignificant in November. There is no obvious correlation between the catches of squid and longitude, but good with latitude.

Fan, Wei; Wu, Yumei; Cui, Xuesen

2009-05-01

2

Age, growth and population structure of the jumbo flying squid Dosidicus gigas in Peruvian waters  

Microsoft Academic Search

Age, growth and population structure of the jumbo flying squid, Dosidicus gigas, from the jig fishery in Peruvian waters in 1992 were determined by reading daily increments in ground and polished sections of statoliths. The squid ranged in size from 192 to 965mm dorsal mantle length (ML) and no squid were older than 1 year. Two size groups were present

J. Argüelles; P. G. Rodhouse; P. Villegas; G. Castillo

2001-01-01

3

Size increment of jumbo flying squid Dosidicus gigas mature females in Peruvian waters, 1989-2004  

NASA Astrophysics Data System (ADS)

Changes in population structure of the jumbo flying squid Dosidicus gigas in Peruvian waters were studied based on size-at-maturity from 1989 to 2004. From 1989 to 1999, mature squid belonging to the medium-sized group prevailed, but from 2001 on, mature squids were larger. This change is not related to the changes in sea surface temperature and we hypothesized that it was caused by the population increase of mesopelagic fishes as prey.

Argüelles, Juan; Tafur, Ricardo; Taipe, Anatolio; Villegas, Piero; Keyl, Friedeman; Dominguez, Noel; Salazar, Martín

2008-10-01

4

Size increment of jumbo flying squid Dosidicus gigas mature females in Peruvian waters, 1989–2004  

Microsoft Academic Search

Changes in population structure of the jumbo flying squid Dosidicus gigas in Peruvian waters were studied based on size-at-maturity from 1989 to 2004. From 1989 to 1999, mature squid belonging to the medium-sized group prevailed, but from 2001 on, mature squids were larger. This change is not related to the changes in sea surface temperature and we hypothesized that it

Juan Argüelles; Ricardo Tafur; Anatolio Taipe; Piero Villegas; Friedeman Keyl; Noel Dominguez; Martín Salazar

2008-01-01

5

Age, Growth and Population Structure of Jumbo Flying Squid, Dosidicus Gigas, Based on Statolith Microstructure Off the Exclusive Economic Zone of Chilean Waters  

Microsoft Academic Search

The jumbo flying squid, Dosidicus gigas, support an important squid fishery off the Exclusive Economic Zone of Chilean waters. However, we only have limited information about their biology. In this study, age, growth and population structure of D. gigas were studied using statoliths from 333 specimens (386 females and 147 males) randomly sampled in the Chinese squid jigging surveys from

X. J. Chen; H. J. Lu; B. L. Liu; Yong Chen

2011-01-01

6

Fishery biology of jumbo flying squid Dosidicus gigas off Costa Rica Dome  

NASA Astrophysics Data System (ADS)

The jumbo flying squid ( Dosidicus gigas) population was surveyed with the help of Chinese squid jigging vessels off the Costa Rica Dome (4°-11°N, 90°-100°W) in 2009 and 2010. The daily catch of D. gigas in the two survey cruises ranged from 0 to 5.5 t and was mostly obtained from the areas bounded by 6°-9°N and 91°-94°W and by 6°30'-7°30'N and 96°-97°W. The sea surface temperature in the areas yielding the most catch ranged from 27.5 to 29°C. The sex ratio of the total catch was 3.75:1 (female: male). The mantle length of the squid ranged from 211 to 355 mm (male) and from 204 to 429 mm (female) with an average of 297.9 and 306.7 mm, respectively. In the relationship of the mantle length (mm) and body weight (g) of the squid, there was no significant difference between sexes. The female and male were at a similar maturity, and most individuals are maturing or have matured with a few females being spent. The size (mantle length) and age at the first sexual maturity were 297 mm and 195 d in females, and less than 211 mm and 130 d in males, respectively. Most of the sampled stomachs (70.6%) had no food remains. The major preys of the squids were fish, cephalopods and crustaceans, with the most abundant Myctophum orientale and D. gigas. The preys in more than 65% of the non-empty sampled stomachs evidenced the cannibalism of D. gigas. The results improved current understanding of the fishery biology of D. gigas off the Costa Rica Dome, which may facilitate the assessment and management of relative fishery resources.

Chen, Xinjun; Li, Jianghua; Liu, Bilin; Li, Gang; Lu, Huajie

2014-06-01

7

Distribution and concentrations of jumbo flying squid ( Dosidicus gigas) off the Peruvian coast between 1991 and 1999  

Microsoft Academic Search

Seasonal changes in the distribution and concentration of jumbo flying squid (Dosidicus gigas) off the Peruvian coast were assessed using catch and effort data from the jigging vessels that worked within the area between 1991 and 1999. The results showed a wide distribution of D. gigas along the coast, the highest concentrations occurred along the coast of northern Peru, from

Anatolio Taipe; Carmen Yamashiro; Luis Mariategui; Pablo Rojas; Cecilia Roque

2001-01-01

8

Age and growth of the neon flying squid, Ommastrephes bartrami, in the North Pacific ocean  

Microsoft Academic Search

Longitudinal sections of statoliths were observed by light microscopy on 237 individuals (158–510 mm mantle length, ML) of Ommastrephes bartrami, obtained from the North Pacific (26 °–46 °N, 143 °E–149 °W) during 1991–1994. The width of each increment sharply decreased from 5–7 ?m to about 1–2 ?m between the 80th and 100th increment, with a transition zone where increments were

Akihiko Yatsu; Satoshi Midorikawa; Takahiro Shimada; Yuji Uozumi

1997-01-01

9

Influence of oceanological conditions on the distribution and biological features of the mass squid species in the South Kuril region  

NASA Astrophysics Data System (ADS)

The distribution of the three mass commercial cephalopod species (the Japanese common squid Todarodes pacificus, the neon flying squid Ommastrephes bartramii, and the boreal clubhook squid Onychoteuthis borealijaponica) on the Pacific side of the South Kuril Islands is analyzed in relation to oceanological conditions using the data of scientific catches of squids and oceanographic observations obtained by Japanese and Russians research vessels in August September of 1994 1999. With respect to the extension of the waters of subtropical origin, three types of oceanological conditions are distinguished: the “conventionally cold” (1996, 1997), “conventionally warm” (1998, 1999) and “conventionally normal” (1994, 1995) conditions. It is shown that conventionally cold years are more favorable for the fishery of the Japanese common squid and the boreal clubhook squid and conventionally normal years are favorable for the fishery of all three squid species, while conventionally cold years are only favorable for the fishery of the neon flying squid. Particular features of the distribution and biology of each of the squid species considered are discussed.

Novikov, Yu. V.; Slobodskoy, E. V.; Shevtsov, G. A.

2007-04-01

10

Giant Squid  

NSDL National Science Digital Library

How do you get two dead Giant Squid the size of a school bus from a fishing boat in Spain to a museum in Washington, DC, USA? Call in the Navy! Find out how Operation Calamari unfolded and how the museum managed to put their new Giant Squid on display. Also included is a Learn More section that provides background information on the scientists recorded in the podcast, lessons, images, and cool facts.

2009-01-01

11

Squid rocket science: How squid launch into air  

NASA Astrophysics Data System (ADS)

Squid not only swim, they can also fly like rockets, accelerating through the air by forcefully expelling water out of their mantles. Using available lab and field data from four squid species, Sthenoteuthis pteropus, Dosidicus gigas, Illex illecebrosus and Loligo opalescens, including sixteen remarkable photographs of flying S. pteropus off the coast of Brazil, we compared the cost of transport in both water and air and discussed methods of maximizing power output through funnel and mantle constriction. Additionally we found that fin flaps develop at approximately the same size range as flight behaviors in these squids, consistent with previous hypotheses that flaps could function as ailerons whilst aloft. S. pteropus acceleration in air (265 body lengths [BL]/s2; 24.5m/s2) was found to exceed that in water (79BL/s2) three-fold based on estimated mantle length from still photos. Velocities in air (37BL/s; 3.4m/s) exceed those in water (11BL/s) almost four-fold. Given the obvious advantages of this extreme mode of transport, squid flight may in fact be more common than previously thought and potentially employed to reduce migration cost in addition to predation avoidance. Clearly squid flight, the role of fin flaps and funnel, and the energetic benefits are worthy of extended investigation.

O'Dor, Ron; Stewart, Julia; Gilly, William; Payne, John; Borges, Teresa Cerveira; Thys, Tierney

2013-10-01

12

NEON Airborne Remote Sensing of Terrestrial Ecosystems  

NASA Astrophysics Data System (ADS)

The National Ecological Observatory Network (NEON) is the continental-scale research platform that will collect information on ecosystems across the United States to advance our understanding and ability to forecast environmental change at the continental scale. One of NEON's observing systems, the Airborne Observation Platform (AOP), will fly an instrument suite consisting of a high-fidelity visible-to-shortwave infrared imaging spectrometer, a full waveform small footprint LiDAR, and a high-resolution digital camera on a low-altitude aircraft platform. NEON AOP is focused on acquiring data on several terrestrial Essential Climate Variables including bioclimate, biodiversity, biogeochemistry, and land use products. These variables are collected throughout a network of 60 sites across the Continental United States, Alaska, Hawaii and Puerto Rico via ground-based and airborne measurements. Airborne remote sensing plays a critical role by providing measurements at the scale of individual shrubs and larger plants over hundreds of square kilometers. The NEON AOP plays the role of bridging the spatial scales from that of individual organisms and stands to the scale of satellite-based remote sensing. NEON is building 3 airborne systems to facilitate the routine coverage of NEON sites and provide the capacity to respond to investigator requests for specific projects. The first NEON imaging spectrometer, a next-generation VSWIR instrument, was recently delivered to NEON by JPL. This instrument has been integrated with a small-footprint waveform LiDAR on the first NEON airborne platform (AOP-1). A series of AOP-1 test flights were conducted during the first year of NEON's construction phase. The goal of these flights was to test out instrument functionality and performance, exercise remote sensing collection protocols, and provide provisional data for algorithm and data product validation. These test flights focused the following questions: What is the optimal remote sensing data collection protocol to meet NEON science requirements? How do aircraft altitude, spatial sampling, spatial resolution, and LiDAR instrument configuration affect data retrievals? What are appropriate algorithms to derive ECVs from AOP data? What methodology should be followed to validate AOP remote sensing products and how should ground truth data be collected? Early test flights were focused on radiometric and geometric calibration as well as processing from raw data to Level-1 products. Subsequent flights were conducted focusing on collecting vegetation chemistry and structure measurements. These test flights that were conducted during 2012 have proved to be extremely valuable for verifying instrument functionality and performance, exercising remote sensing collection protocols, and providing data for algorithm and science product validation. Results from these early flights are presented, including the radiometric and geometric calibration of the AOP instruments. These 2012 flight campaigns are just the first of a series of test flights that will take place over the next several years as part of the NEON observatory construction. Lessons learned from these early campaigns will inform both airborne and ground data collection methodologies for future campaigns as well as guide the AOP sampling strategy before NEON enters full science operations.

Kampe, T. U.; Leisso, N.; Krause, K.; Karpowicz, B. M.

2012-12-01

13

Science Nation: Glowing Squid  

NSDL National Science Digital Library

In deep ocean waters, it's sometimes difficult to hide from predators. That's why so many sea creatures have evolved extraordinary methods of disguise. Cephalopods, such as octopus, squid and cuttlefish, are big on camouflage, by day or night. In fact, the Hawaiian bobtail squid has several means of stealthy self- preservation. With support from the National Science Foundation (NSF), a team from the University of Wisconsin-Madison study one bobtail squid camouflage scheme; one that glows in the dark!

14

Crustal neon - A striking uniformity  

Microsoft Academic Search

As part of the effort to characterize terrestrial fluid reservoirs in terms of their noble gas content, several methane-rich natural gases collected throughout Alberta (Canada) and the Tucamari and San Juan Basins of New Mexico (USA) were analyzed. A well-defined nucleogenic (crustal) neon component was identified. This neon component was produced from (alpha, n) and (n, alpha) nuclear interactions involving

B. M. Kennedy; H. Hiyagon; J. H. Reynolds

1990-01-01

15

Future Medicine From Squid  

NSDL National Science Digital Library

This news article reports an exciting discovery about a toxic molecule found in both humans and in the Hawaiian bobtail squid that may hold the medical key for critical organ development and the immune system. Margaret McFall-Ngai, funded by the National Institute of Health, is studying the toxic molecule that causes tissue damage in human diseases such as whooping cough and gonorrhea and, is found to generate the light-producing organ in the Hawaiian bobtail squid.

Millot, Charmaine; Times, The E.

16

Crustal neon - A striking uniformity  

NASA Astrophysics Data System (ADS)

As part of the effort to characterize terrestrial fluid reservoirs in terms of their noble gas content, several methane-rich natural gases collected throughout Alberta (Canada) and the Tucamari and San Juan Basins of New Mexico (USA) were analyzed. A well-defined nucleogenic (crustal) neon component was identified. This neon component was produced from (alpha, n) and (n, alpha) nuclear interactions involving nuclei of O and F, as was shown by Wetherill (1954). The inferred upper limit isotopic composition is Ne-21/Ne-22 = 0.47 + or - 0.01, for the case of Ne-20/Ne-22 = 0.0. The composition is distinct from the air neon and from neon observed in MORB basalts.

Kennedy, B. M.; Hiyagon, H.; Reynolds, J. H.

1990-06-01

17

Subranging scheme for SQUID sensors  

NASA Technical Reports Server (NTRS)

A readout scheme for measuring the output from a SQUID-based sensor-array using an improved subranging architecture that includes multiple resolution channels (such as a coarse resolution channel and a fine resolution channel). The scheme employs a flux sensing circuit with a sensing coil connected in series to multiple input coils, each input coil being coupled to a corresponding SQUID detection circuit having a high-resolution SQUID device with independent linearizing feedback. A two-resolution configuration (course and fine) is illustrated with a primary SQUID detection circuit for generating a fine readout, and a secondary SQUID detection circuit for generating a course readout, both having feedback current coupled to the respective SQUID devices via feedback/modulation coils. The primary and secondary SQUID detection circuits function and derive independent feedback. Thus, the SQUID devices may be monitored independently of each other (and read simultaneously) to dramatically increase slew rates and dynamic range.

Penanen, Konstantin I. (Inventor)

2008-01-01

18

SQUID linear amplifier circuit simulations  

SciTech Connect

This paper presents numerical simulations of a single stage of a linear SQUID amplifier. The amplifier stage is fabricated in thin film technology, and consists of two asymmetric SQUIDs placed in the push-pull configuration. It was found that the Q of the tank circuit formed by SQUID inductance and a parasitic strip-line capacitance must be reduced to unity to avoid hysteretic operation. A load line analysis has determined the amplifier operating point and SQUID inductance which yield optimum linearity.

Gershenson, M.; Hastings, R.; Schneider, R.; Sorensen, E.; Sweeny, M.

1983-09-01

19

Geophysical applications of squids  

SciTech Connect

Present and potential geophysical applications of Superconducting Quantum Interference Devices (SQUIDs) include remote reference magnetotellurics, controlledsource electromagnetic sounding, airborne gradiometry, gravity gradiometers, rock magnetism, paleomagnetism, piezomagnetism, tectonomagnetism, the location of hydrofractures for hot dry rock geothermal energy and enhanced oil and gas recovery, the detection of internal ocean waves, and underwater magnetotellurics.

Clarke, J.

1983-05-01

20

Low-noise SQUID  

DOEpatents

The present invention comprises a high-transition-temperature superconducting device having low-magnitude low-frequency noise-characteristics in magnetic fields comprising superconducting films wherein the films have a width that is less than or equal to a critical width, w.sub.C, which depends on an ambient magnetic field. For operation in the Earth's magnetic field, the critical width is about 6 micrometers (.mu.m). When made with film widths of about 4 .mu.m an inventive high transition-temperature, superconducting quantum interference device (SQUID) excluded magnetic flux vortices up to a threshold ambient magnetic field of about 100 microTesla (.mu.T). SQUIDs were fabricated having several different film strip patterns. When the film strip width was kept at about 4 .mu.m, the SQUIDs exhibited essentially no increase in low-frequency noise, even when cooled in static magnetic fields of magnitude up to 100 .mu.T. Furthermore, the mutual inductance between the inventive devices and a seven-turn spiral coil was at least 85% of that for inductive coupling to a conventional SQUID.

Dantsker, Eugene (Torrance, CA); Clarke, John (Berkeley, CA)

2000-01-01

21

Neon colors illuminate reading units.  

PubMed

The effect of syllable-size reading units on neon color was investigated in 6 experiments. The stimuli consisted of 5- or 7-letter words or pseudowords with a syllable break either just before or just after the middle (target) letter. The target letter was overlaid with a plaid of red and green lines that gave it an ambiguous neon color. The letters preceding the target were overlaid with a monochromatic grid (red or green), and the letters following the target were overlaid with the other color. Ss were significantly more likely to judge the target as more similar to the color of other letters within its syllable than colors of letters outside that unit. The effect was shown not to be an artifact of guessing strategy or eye movements. Word structure determined by orthography and morphology affected neon colors, but no effect was found for purely phonological units. PMID:2144573

Prinzmetal, W

1990-08-01

22

Solar Helium and Neon in the Earth.  

National Technical Information Service (NTIS)

Neon isotopic compositions in mantle-derived samples commonly are enriched in (20)Ne and (21)Ne relative to (22)Ne compared with atmospheric neon ((20)Ne/(22)Ne and (21)Ne/(22)Ne ratios in atmospheric neon are 9.8 and 0.029, respectively), together with s...

M. Honda I. Mcdougall D. B. Patterson

1994-01-01

23

Dissect Your Squid and Eat It Too!  

ERIC Educational Resources Information Center

Introduces a science lab activity in which students dissect fresh squids in groups of four and observe the anatomy. Parent volunteers cook the squid mantle for kids to taste. Includes directions for squid dissection. (YDS)

McGinnis, Patricia

2001-01-01

24

Code-division SQUID multiplexing  

NASA Astrophysics Data System (ADS)

Multiplexed superconducting quantum interference device (SQUID) readout systems are critical for measuring large arrays of superconducting transition-edge sensors (TES). We demonstrate a code-division SQUID multiplexing (CDM) architecture that is modulated by Walsh codes. Measurements and simulations of a prototype multiplexer show that this modulation scheme is not degraded by SQUID-noise aliasing, suppresses parasitic pickup, and has low levels of crosstalk. These properties enable this architecture to scale to large TES arrays. Furthermore, CDM modulation suppresses the 1/f knee in the noise to below 20 mHz, suggesting the use of this circuit for low-frequency-noise mitigation in more general SQUID applications.

Niemack, M. D.; Beyer, J.; Cho, H. M.; Doriese, W. B.; Hilton, G. C.; Irwin, K. D.; Reintsema, C. D.; Schmidt, D. R.; Ullom, J. N.; Vale, L. R.

2010-04-01

25

Neon isotopes in submarine basalts  

Microsoft Academic Search

Very large neon isotopic anomalies have been accurately measured in mid-ocean ridge basalt glassy samples from diverse locations worldwide. Values for 20Ne\\/22Ne range up to ~ 13 and 21Ne\\/22Ne values range up to ~ 0.07 (present atmospheric values are 20Ne\\/22Ne = 9.8 and 21Ne\\/22Ne = 0.029). The data are highly correlated in the 20Ne\\/22Ne-21Ne\\/22Ne diagram, independent of sample location. Loihi

Philippe Sarda; Thomas Staudacher; Claude J. Allègre

1988-01-01

26

In Search of the Giant Squid  

NSDL National Science Digital Library

The truth about this mysterious giant based on the exhibit by the National Museum of Natural History. A complete guide to the giant squid, including the different species of squid, how squid move, eat, and defend themselves, as well as photographs from the exhibit. Features also include information on the vessels and equipment used to investigate the giant squid, the locations where the giant squid were searched for, and a daily journal of the expedition.

27

Graphoepitaxial high-Tc SQUIDs  

NASA Astrophysics Data System (ADS)

The fabrication process and physical properties of graphoepitaxially engineered high-Tc direct current superconducting quantum interferometer devices (DC SQUIDs) are studied. Double buffer layers, each comprising a graphoepitaxial seed layer of YBa2Cu3O7?x and an epitaxial blocking layer of SrTiO3, were deposited over textured step edges on (001) surfaces of MgO substrates. Scanning electron microscopy and high-resolution transmission electron microscopy were used to investigate the microstructural properties of DC SQUIDs with graphoepitaxial Josephson junctions. Both direct coupled and inductively coupled high-Tc DC SQUIDs with graphoepitaxial step edge junctions and flux transformers were studied.

Faley, M. I.; Meertens, D.; Poppe, U.; Dunin-Borkowski, R. E.

2014-05-01

28

Tracking Electromagnetic Energy With SQUIDs.  

National Technical Information Service (NTIS)

A superconducting quantum interference device (SQUID) is a gadget used to measure extremely weak signals, specifically magnetic flux. It can detect subtle changes in energy, up to 100 billion times weaker than the electromagnetic energy required to move a...

2005-01-01

29

Neon Ion Beam Lithography (NIBL).  

PubMed

Existing techniques for electron- and ion-beam lithography, routinely employed for nanoscale device fabrication and mask/mold prototyping, do not simultaneously achieve efficient (low fluence) exposure and high resolution. We report lithography using neon ions with fluence <1 ion/nm(2), ?1000× more efficient than using 30 keV electrons, and resolution down to 7 nm half-pitch. This combination of resolution and exposure efficiency is expected to impact a wide array of fields that are dependent on beam-based lithography. PMID:21899279

Winston, Donald; Manfrinato, Vitor R; Nicaise, Samuel M; Cheong, Lin Lee; Duan, Huigao; Ferranti, David; Marshman, Jeff; McVey, Shawn; Stern, Lewis; Notte, John; Berggren, Karl K

2011-10-12

30

Small scale demand type neon liquefaction plant  

NASA Technical Reports Server (NTRS)

Low-temperature measurement of the thermal conductivity of insulating materials is generally made using a boil-off calorimetry technique involving liquid hydrogen (LH2). Liquid neon (LNe) has nearly the same normal boiling point as LH2, but has a much larger heat of vaporization, allowing extended run times. The main drawback of using LNe has been its excessive cost; $170.00 versus $1.50/l for LH2 (1989 prices). A neon liquefaction plant has been designed and constructed to capture, purify, and refrigerate the neon boil-off from calorimetry experiments. Recycling the neon reduces operating costs to approximately $20/l. The system consists of a purification section, a heat exchanger, LNe and LH2 storage dewars, and a fully automated control system. After purification, neon is liquified in the heat exchanger by LH2 flowing countercurrently through stainless steel cooling coils. Hydrogen flow is automatically adjusted to keep the neon at its normal saturation temperature, 27 K. The liquid neon is then stored in a dewar placed directly below the heat exchanger.

Dube, W. P.; Slifka, A. J.; Bitsy, R. M.; Sparks, L. L.; Johnson, K. B.

1990-01-01

31

Small scale demand type neon liquefaction plant  

NASA Astrophysics Data System (ADS)

Low-temperature measurement of the thermal conductivity of insulating materials is generally made using a boil-off calorimetry technique involving liquid hydrogen (LH2). Liquid neon (LNe) has nearly the same normal boiling point as LH2, but has a much larger heat of vaporization, allowing extended run times. The main drawback of using LNe has been its excessive cost; $170.00 versus $1.50/l for LH2 (1989 prices). A neon liquefaction plant has been designed and constructed to capture, purify, and refrigerate the neon boil-off from calorimetry experiments. Recycling the neon reduces operating costs to approximately $20/l. The system consists of a purification section, a heat exchanger, LNe and LH2 storage dewars, and a fully automated control system. After purification, neon is liquified in the heat exchanger by LH2 flowing countercurrently through stainless steel cooling coils. Hydrogen flow is automatically adjusted to keep the neon at its normal saturation temperature, 27 K. The liquid neon is then stored in a dewar placed directly below the heat exchanger.

Dube, W. P.; Slifka, A. J.; Bitsy, R. M.; Sparks, L. L.; Johnson, K. B.

32

Flying wings / flying fuselages.  

National Technical Information Service (NTIS)

The present paper has documented the historical relationships between various classes of all lifting vehicles, which includes the flying wing, all wing, tailless, lifting body, and lifting fuselage. The diversity in vehicle focus was to ensure that all ve...

R. M. Wood S. X. S. Bauer

2001-01-01

33

NEON Citizen Science: Planning and Prototyping  

NASA Astrophysics Data System (ADS)

The National Ecological Observatory Network (NEON) will be a national resource for ecological research and education. NEON citizen science projects are being designed to increase awareness and educate citizen scientists about the impacts of climate change, land-use change, and invasive species on continental-scale ecological processes as well as expand NEON data collection capacity by enabling laypersons to collect geographically distributed data. The citizen science area of the NEON web portal will enable citizen scientists to collect, contribute, interpret, and visualize scientific data, as well as access training modules, collection protocols and targeted learning experiences related to citizen science project topics. For NEON, citizen science projects are a means for interested people to interact with and contribute to NEON science. Investigations at vast spatial and temporal scales often require rapid acquisition of large amounts of data from a geographically distributed population of "human sensors." As a continental-scale ecological observatory, NEON is uniquely positioned to develop strategies to effectively integrate data collected by non-scientists into scientific databases. Ultimately, we plan to work collaboratively to transform the practice of science to include "citizens" or non-scientists in the process. Doing science is not limited to scientists, and breaking down the barriers between scientists and citizens will help people better understand the power of using science in their own decision making. In preparation for fully developing the NEON citizen science program, we are partnering with Project BudBurst (PBB), a citizen science project focused on monitoring plant phenology. The educational goals of PBB are to: (1) increase awareness of climate change, (2) educate citizen scientists about the impacts of climate change on plants and the environment, and (3) increase science literacy by engaging participants in the scientific process. Phenology was chosen as the focus of this citizen science campaign because it is a visible and comprehensible way of demonstrating the effects of climate change. In addition, plants are readily accessible in nearly every neighborhood and park, and wild area across the continent, so people can make observations whether they live near an inner city park or in the rural countryside. Recently, NEON developed data visualization tools for Project BudBurst to engage citizen science participants in "doing science" beyond data collection. By prototyping NEON citizen science through Project BudBurst, NEON is developing a better understanding of how to build a citizen science program that addresses areas of awareness, mastery, and leadership of scientific information like that which NEON will produce over the next 30 years.

Newman, S. J.; Henderson, S.; Gardiner, L. S.; Ward, D.; Gram, W.

2011-12-01

34

SQUID magnetometers for low-frequency applications  

Microsoft Academic Search

We present a novel formulation for SQUID operation, which enables us to evaluate and compare the sensitivity and applicability of different devices. SQUID magnetometers for low-frequency applications are analyzed, taking into account the coupling circuits and electronics. We discuss nonhysteretic and hysteretic single-junction rf SQUIDs, but the main emphasis is on the dynamics, sensitivity, and coupling considerations of dc-SQUID magnetometers.

Tapani Ryhänen; Heikki Seppä; Risto Ilmoniemi; Jukka Knuutila

1989-01-01

35

Spanish Market for U.S. Squid.  

National Technical Information Service (NTIS)

Spain is the eighth largest consumer of fishery products in the world and second, behind Japan, in the consumption of squid and squid products. In recent years, the Spanish squid catch has shifted from species found in the waters off North Africa and Nort...

W. Folsom M. Miller

1987-01-01

36

Simple, Low-Noise uhf Squid Magnetometer.  

National Technical Information Service (NTIS)

The development of a smiple, rugged, low-noise SQUID magnetometer, biased in the UHF range, and constructed around the extensively used two-hole SQUID ring. This design is novel, both in the manner in which rf is coupled to the SQUID ring, and in the abil...

L. D. Jackel, T. D. Clark

1975-01-01

37

A 37 channel DC SQUID magnetometer system  

Microsoft Academic Search

A 37-channel DC SQUID magnetometer system has been built for biomagnetic studies. The SQUID loop of each magnetometer serves as the active sensing element, thereby eliminating the need for flux coupling circuits. The magnetometers are located ≃3 cm above the outer dewar bottom. The SQUIDs are directly coupled to a highly simplified readout electronics using only five wires per channel;

H. Koch; R. Cantor; D. Drung; S. N. Erne; K. P. Matthies; M. Peters; T. Ryhanen; H. J. Scheer; H. D. Hahlbohm

1991-01-01

38

REVIEW ARTICLE: SQUIDs for nondestructive evaluation  

Microsoft Academic Search

We attempt a comprehensive review of all published research in nondestructive evaluation (NDE) performed with the superconducting quantum interference device (SQUID) magnetometer since the first work was reported in the mid-1980s. The SQUID is the most sensitive detector of magnetic flux known. The energy sensitivity of the SQUID may make it the most sensitive detector of any kind. The research

W. G. Jenks; S. S. H. Sadeghi; J. P. Wikswo Jr.

1997-01-01

39

Squid technology and brain research  

NASA Astrophysics Data System (ADS)

Since 1968, SQUIDs have been used in many low temperature laboratories as ultrasensitive detectors of magnetic flux. Multi-SQUID applications, however, have materialized only recently. Neuromagnetometers are now available covering the whole head in a helmet-like fashion with over 100 superconducting sensors. These instruments are used in magnetoencephalography (MEG) for recording the very weak fields, on the order of 100 fT, which are produced by electrical currents flowing in the brain's neural networks. From the externally measured magnetic field distribution it is possible to calculate the active sites in the cortex. The spatial resolution of MEG is, under favorable conditions, 4-5 mm and the temporal accuracy is better than 1 ms. The method can thus be employed for noninvasive studies of basic neurophysiological functions and information processing in the human brain. Clinical applications are emerging as well. Two examples of recent work using our 122-SQUID magnetometer are discussed.

Lounasma, Olli V.; Knuutila, Jukka; Salmelin, Riitta

1994-03-01

40

Solar helium and neon in the Earth  

NASA Technical Reports Server (NTRS)

Neon isotopic compositions in mantle-derived samples commonly are enriched in (20)Ne and (21)Ne relative to (22)Ne compared with atmospheric neon ((20)Ne/(22)Ne and (21)Ne/(22)Ne ratios in atmospheric neon are 9.8 and 0.029, respectively), together with significant primordial (3)He. Such results have been obtained on MORB's, intraplate plume-related oceanic island basalts, backarc basin basalts, mantle xenoliths, ancient diamonds and CO2 well gases (e.g., 1 - 8). The highest (20)Ne/(22)Ne ratio observed in MORB glasses (= 13.6 plus or minus 1.3 is close to the solar value (= 13.6, as observed in solar wind). In order to explain the enrichment of (20)Ne and (21)Ne relative to atmospheric neon for samples derived from the mantle, it is necessary to postulate the presence of at least two distinct non-atmospheric components. The two most likely candidates are solar and nucleogenic ((20)Ne/(22)Ne solar = 13.6 (21)Ne/(22)Ne solar = 0.032, (20)Ne/(22)Ne nucleogenic = 2.5 and (21)Ne/(22)Ne nucleogenic = 32). This is because solar neon is the only known component with a (20)Ne/(22)Ne ratio greater than both the atmospheric value and that observed in samples derived from the mantle. Nucleogenic neon is well known to elevate (21)Ne/(22)Ne ratios. Neon isotopic signatures observed in mantle-derived samples can be accounted for by mixing of the three neon end members: solar, nucleogenic and atmospheric.

Honda, M.; Mcdougall, I.; Patterson, D. B.

1994-01-01

41

Solar helium and neon in the Earth  

NASA Astrophysics Data System (ADS)

Neon isotopic compositions in mantle-derived samples commonly are enriched in (20)Ne and (21)Ne relative to (22)Ne compared with atmospheric neon ((20)Ne/(22)Ne and (21)Ne/(22)Ne ratios in atmospheric neon are 9.8 and 0.029, respectively), together with significant primordial (3)He. Such results have been obtained on MORB's, intraplate plume-related oceanic island basalts, backarc basin basalts, mantle xenoliths, ancient diamonds and CO2 well gases (e.g., 1 - 8). The highest (20)Ne/(22)Ne ratio observed in MORB glasses (= 13.6 plus or minus 1.3 is close to the solar value (= 13.6, as observed in solar wind). In order to explain the enrichment of (20)Ne and (21)Ne relative to atmospheric neon for samples derived from the mantle, it is necessary to postulate the presence of at least two distinct non-atmospheric components. The two most likely candidates are solar and nucleogenic ((20)Ne/(22)Ne solar = 13.6 (21)Ne/(22)Ne solar = 0.032, (20)Ne/(22)Ne nucleogenic = 2.5 and (21)Ne/(22)Ne nucleogenic = 32). This is because solar neon is the only known component with a (20)Ne/(22)Ne ratio greater than both the atmospheric value and that observed in samples derived from the mantle. Nucleogenic neon is well known to elevate (21)Ne/(22)Ne ratios. Neon isotopic signatures observed in mantle-derived samples can be accounted for by mixing of the three neon end members: solar, nucleogenic and atmospheric.

Honda, M.; McDougall, I.; Patterson, D. B.

42

Flying wings / flying fuselages  

NASA Technical Reports Server (NTRS)

The present paper has documented the historical relationships between various classes of all lifting vehicles, which includes the flying wing, all wing, tailless, lifting body, and lifting fuselage. The diversity in vehicle focus was to ensure that all vehicle types that map have contributed to or been influenced by the development of the classical flying wing concept was investigated. The paper has provided context and perspective for present and future aircraft design studies that may employ the all lifting vehicle concept. The paper also demonstrated the benefit of developing an understanding of the past in order to obtain the required knowledge to create future concepts with significantly improved aerodynamic performance.

Wood, Richard M.; Bauer, Steven X. S.

2001-01-01

43

Cold SQUIDs and hot samples  

SciTech Connect

Low transition temperature (low-{Tc}) and high-{Tc} Superconducting QUantum Interference Devices (SQUIDs) have been used to perform high-resolution magnetic measurements on samples whose temperatures are much higher than the operating temperatures of the devices. Part 1 of this work focuses on measurements of the rigidity of flux vortices in high-{Tc} superconductors using two low-{Tc} SQUIDs, one on either side of a thermally-insulated sample. The correlation between the signals of the SQUIDs is a direct measure of the extent of correlation between the movements of opposite ends of vortices. These measurements were conducted under the previously-unexplored experimental conditions of nominally-zero applied magnetic field, such that vortex-vortex interactions were unimportant, and with zero external current. At specific temperatures, the authors observed highly-correlated noise sources, suggesting that the vortices moved as rigid rods. At other temperatures, the noise was mostly uncorrelated, suggesting that the relevant vortices were pinned at more than one point along their length. Part 2 describes the design, construction, performance, and applications of a scanning high-{Tc} SQUID microscope optimized for imaging room-temperature objects with very high spatial resolution and magnetic source sensitivity.

Lee, T.S.C. [Univ. of California, Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley national Lab., CA (United States). Materials Sciences Div.

1997-05-01

44

Bright Squid Found In Hawaii  

NSDL National Science Digital Library

This 2004 CBS news article gives a brief summary of the initial discovery of a Hawaiian bobtail squid with reflective plates that form a built-in light, which is thought to confuse predators. The article also discusses possible mechanisms for the light production.

Schmid, Randolph E.; News, Cbs

45

Helium and Neon in Comets  

NASA Technical Reports Server (NTRS)

Two comets were observed with EUVE in late 1994. Both comet Mueller and comet Borrelly are short-period comets having well established orbital elements and accurate ephemerides. Spectra of 40 ksec were taken of each. No evidence for emission lines from either Helium or Neon was detected. We calculated limits on the production rates of these atoms (relative to solar) assuming a standard isotropic outflow model, with a gas streaming speed of 1 km/s. The 3-sigma (99.7% confidence) limits (1/100,000 for He, 0.8 for Ne) are based on a conservative estimate of the noise in the EUVE spectra. They are also weakly dependent on the precise pointing and tracking of the EUVE field of view relative to the comet during the integrations. These limits are consistent with ice formation temperatures T greater than or equal to 30 K, as judged from the gas trapping experiments of Bar-Nun. For comparison, the solar abundances of these elements are He/O = 110, Ne/O = 1/16. Neither limit was as constraining as we had initially hoped, mainly because comets Mueller and Borrelly were intrinsically less active than anticipated.

Jewitt, David

1996-01-01

46

Bulk excitons in solid neon: Theory  

Microsoft Academic Search

In a recent paper Saile and Koch present a detailed experimental reinvestigation of the excitonic spectrum of solid neon. With respect to a previous work, relevant corrections are introduced in the case of the n=1 excitonic transitions. Saile and Koch compare their results with theoretical studies which were, however, based on the previous data. Other relevant theoretical works have been

L. Resca; R. Resta

1980-01-01

47

SQUID multiplexers for transition-edge sensors  

Microsoft Academic Search

We review the superconducting quantum interface device (SQUID) multiplexer schemes that are being developed to instrument large-format arrays of superconducting transition-edge sensors. We discuss the choice of an orthogonal basis set to represent the multiplexed signal (such as time or frequency) and the practical issues of implementation, including bandwidth-limiting filters, SQUID noise, and power dissipation.

K. D. Irwin

2002-01-01

48

Magnetoencephalography with an Array of Squid Sensors.  

National Technical Information Service (NTIS)

A novel installation was developed for unshielded measurements of the neuromagnetic field near the scape with a cryogenic system incorporating nine SQUID sensors in a single dewar. Five dc-SQUIDs measure the field of interest sensed by a radial array of f...

S. J. Williamson M. Pelizzone Y. Okada L. Kaufman D. B. Crum

1984-01-01

49

ASA's Chandra Neon Discovery Solves Solar Paradox  

NASA Astrophysics Data System (ADS)

NASA's Chandra X-ray Observatory survey of nearby sun-like stars suggests there is nearly three times more neon in the sun and local universe than previously believed. If true, this would solve a critical problem with understanding how the sun works. "We use the sun to test how well we understand stars and, to some extent, the rest of the universe," said Jeremy Drake of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "But in order to understand the sun, we need to know exactly what it is made of," he added. It is not well known how much neon the sun contains. This is critical information for creating theoretical models of the sun. Neon atoms, along with carbon, oxygen and nitrogen, play an important role in how quickly energy flows from nuclear reactions in the sun's core to its edge, where it then radiates into space. Chandra X-ray Spectrum of II Pegasi Chandra X-ray Spectrum of II Pegasi The rate of this energy flow determines the location and size of a crucial stellar region called the convection zone. The zone extends from near the sun's surface inward approximately 125,000 miles. The zone is where the gas undergoes a rolling, convective motion much like the unstable air in a thunderstorm. "This turbulent gas has an extremely important job, because nearly all of the energy emitted at the surface of the sun is transported there by convection," Drake said. The accepted amount of neon in the sun has led to a paradox. The predicted location and size of the solar convection zone disagree with those deduced from solar oscillations. Solar oscillations is a technique astronomers previously relied on to probe the sun's interior. Several scientists have noted the problem could be fixed if the abundance of neon is in fact about three times larger than currently accepted. Attempts to measure the precise amount of neon in the Sun have been frustrated by a quirk of nature; neon atoms in the Sun give off no signatures in visible light. However, in a gas heated to millions of degrees, neon shines brightly in X-rays. Stars like the sun are covered in this super-heated gas that is betrayed by the white corona around them during solar eclipses. However, observations of the sun's corona are very difficult to analyze. Labeled Illustration of Convection in Sun-like Star Labeled Illustration of Convection in Sun-like Star To probe the neon content, Drake and his colleague Paola Testa of the Massachusetts Institute of Technology in Cambridge, Mass., observed 21 sun-like stars within a distance of 400 light years from Earth. These local stars and the sun should contain about the same amount of neon when compared to oxygen. However, these close stellar kin were found to contain on average almost three times more neon than is believed for the sun. "Either the sun is a freak in its stellar neighborhood, or it contains a lot more neon than we think," Testa said. These Chandra results reassured astronomers the detailed physical theory behind the solar model is secure. Scientists use the model of the sun as a basis for understanding the structure and evolution of other stars, as well as many other areas of astrophysics. "If the higher neon abundance measured by Drake and Testa is right, then it is a simultaneous triumph for Chandra and for the theory of how stars shine," said John Bahcall of the Institute for Advanced Study, Princeton, N.J. Bahcall is an expert in the field who was not involved in the Chandra study. Drake is lead author of the study published in this week's issue of the journal Nature. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the agency's Science Mission Directorate. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass. Additional information and images are available at: http://chandra.harvard.edu and http://chandra.nasa.gov

2005-07-01

50

Aperture effects in squid jet propulsion.  

PubMed

Squid are the largest jet propellers in nature as adults, but as paralarvae they are some of the smallest, faced with the inherent inefficiency of jet propulsion at a low Reynolds number. In this study we describe the behavior and kinematics of locomotion in 1 mm paralarvae of Dosidicus gigas, the smallest squid yet studied. They swim with hop-and-sink behavior and can engage in fast jets by reducing the size of the mantle aperture during the contraction phase of a jetting cycle. We go on to explore the general effects of a variable mantle and funnel aperture in a theoretical model of jet propulsion scaled from the smallest (1 mm mantle length) to the largest (3 m) squid. Aperture reduction during mantle contraction increases propulsive efficiency at all squid sizes, although 1 mm squid still suffer from low efficiency (20%) because of a limited speed of contraction. Efficiency increases to a peak of 40% for 1 cm squid, then slowly declines. Squid larger than 6 cm must either reduce contraction speed or increase aperture size to maintain stress within maximal muscle tolerance. Ecological pressure to maintain maximum velocity may lead them to increase aperture size, which reduces efficiency. This effect might be ameliorated by nonaxial flow during the refill phase of the cycle. Our model's predictions highlight areas for future empirical work, and emphasize the existence of complex behavioral options for maximizing efficiency at both very small and large sizes. PMID:24501132

Staaf, Danna J; Gilly, William F; Denny, Mark W

2014-05-01

51

First demonstration of transcontinental SQUID magnetometry (Invited)  

NASA Astrophysics Data System (ADS)

We present the first simultaneous measurements from an ultra-sensitive dual-node transcontinental SQUID magnetometer network, available in real time on the internet. A three-axis low temperature SQUID sensor at LSBB Underground Research Laboratory, Rustrel, France (43.841 N, 5.484 E) and a two-axis high temperature SQUID sensor at SANSA Space Science in Hermanus, South Africa (34.424 S, 19.223 E), form the sensitive nodes of the network. Data are measured and GPS time stamped continuously at 125 Hz. The low-Tc SQUID at LSBB URL (known as a [SQUID]2 system) is inside a shielded steel capsule underneath 500 meters of karstic rock, which allows a low magnetic noise floor. The less sensitive high-Tc SQUID at SANSA Space Science is completely unshielded, and housed only in a magnetically neutral hut, 50 metres from a calibrated fluxgate node of the INTERMAGNET network, to protect it against the weather. The network, which is more sensitive than observatory fluxgate magnetometers, detects Earth's magnetosphere pulsations, Schumann waves, mesopause resonance, breathing modes of the Earth and oceanic swell. Our goal is further to extract directional or polarization information if earthquake precursors are observed again, as with the Sichuan-Wenchuan earthquake on 12 May 2008. In the medium term, we are exploring the possibility to extend the network with more spatially distributed SQUID sensors, such as at the South African National Antarctic Expedition's SANAE IV base in Antarctica.

Fourie, C.; Febvre, P.; Pozzo di Borgo, E.; Waysand, G.; Gouws, D.; Saunderson, E.; Henry, S.; Gaffet, S.; Janse van Vuuren, L.; Lochner, E. T.; Matladi, T.; Kwisanga, C.

2013-12-01

52

Diffusion of neon in white dwarf stars.  

PubMed

Sedimentation of the neutron rich isotope 22Ne may be an important source of gravitational energy during the cooling of white dwarf stars. This depends on the diffusion constant for 22Ne in strongly coupled plasma mixtures. We calculate self-diffusion constants D(i) from molecular dynamics simulations of carbon, oxygen, and neon mixtures. We find that D(i) in a mixture does not differ greatly from earlier one component plasma results. For strong coupling (coulomb parameter ?> few), D(i) has a modest dependence on the charge Z(i) of the ion species, D(i)?Z(i)(-2/3). However, D(i) depends more strongly on Z(i) for weak coupling (smaller ?). We conclude that the self-diffusion constant D(Ne) for 22Ne in carbon, oxygen, and neon plasma mixtures is accurately known so that uncertainties in D(Ne) should be unimportant for simulations of white dwarf cooling. PMID:21230741

Hughto, J; Schneider, A S; Horowitz, C J; Berry, D K

2010-12-01

53

Powering neon lamps through piezoelectric transformers  

Microsoft Academic Search

An investigation of the piezoelectric high-voltage ratio transformer as a potential component for powering neon lamps is discussed. The attractiveness of the piezoelectric technology is primarily the extreme simplicity of the resulting components, which are easy to reproduce in mass production, compared to the widely-used wire-wound ferrite transformers. Furthermore, on account of the electric network behaviour of a piezotransformer, the

P. J. M. Smidt; J. L. Duarte

1996-01-01

54

Dynamic optogalvanic effect in a neon plasma  

SciTech Connect

The authors construct a model of the dynamic optogalvanic effect. On the basis of this model they then analyze the experimental data obtained in a neon glow-discharge plasma whose excited states are generated by collisional and ionizational determinants and by dye laser pulsed resonant radiation. Equations are given for population inversions, processes of spontaneous decay including radiative capture, and transitions between neighboring states due to atom-atom and electron-atom collisions.

Zaitsev, N.K.; Pushkarev, V.A.; Shaparev, N.Ya.

1987-08-01

55

Binary collision model for neon Auger spectra from neon ion bombardment of the aluminum surface  

NASA Astrophysics Data System (ADS)

A model is developed to account for the angle-resolved Auger spectra from neon ion bombardment of the aluminum surface recently obtained by Pepper and Aron. The neon is assumed to be excited in a single asymmetric neon-aluminum collision and scattered back into the vacuum where it emits an Auger electron. The velocity of the Auger electron acquires a Doppler shift by virtue of the emission from a moving source. The dependence of the Auger peak shape and energy on the incident ion energy, angle of incidence and on the angle of Auger electron emission with respect to the surface is presented. Satisfactory agreement with the angle resolved experimental observations is obtained. The dependence of the angle-integrated Auger yield on the incident ion energy and angle of incidence is also obtained and shown to be in satisfactory agreement with available experimental evidence.

Pepper, Stephen V.

1986-04-01

56

Binary collision model for neon Auger spectra from neon ion bombardment of the aluminum surface  

NASA Technical Reports Server (NTRS)

A model is developed to account for the angle-resolved Auger spectra from neon ion bombardment of the aluminum surface recently obtained by Pepper and Aron. The neon is assumed to be excited in a single asymmetric neon-aluminum-collision and scattered back into the vacuum where it emits an Auger electron. The velocity of the Auger electron acquires a Doppler shift by virtue of the emission from a moving source. The dependence of the Auger peak shape and energy on the incident ion energy, angle of incidence and on the angle of Auger electron emission with respect to the surface is presented. Satisfactory agreement with the angle resolved experimental observations is obtained. The dependence of the angle-integrated Auger yield on the incident ion energy and angle of incidence is also obtained and shown to be in satisfactory agreement with available experimental evidence.

Pepper, S. V.

1986-01-01

57

The neon gas field ion source—a first characterization of neon nanomachining properties  

NASA Astrophysics Data System (ADS)

At the Charged Particle Optics Conference (CPO7) in 2006, a novel trimer based helium gas field ion source (GFIS) was introduced for use in a new helium ion microscope (HIM), demonstrating the novel source performance attributes and unique imaging applications of the HIM (Hill et al., 2008 [1]; Livengood et al., 2008 [2]). Since that time there have been numerous enhancements to the HIM source and platform demonstrating resolution scaling into the sub 0.5 nm regime (Scipioni et al., 2009 [3]; Pickard et al., 2010 [4]). At this Charged Particle Optics Conference (CPO8) we will be introducing a neon version of the trimer-GFIS co-developed by Carl Zeiss SMT and Intel Corporation. The neon source was developed as a possible supplement to the gallium liquid metal ion source (LMIS) used today in most focused ion beam (FIB) systems (Abramo et al., 1994 [5]; Young et al.,1998 [6]). The neon GFIS source has low energy spread (˜1 eV) and a small virtual source size (sub-nanometer), similar to that of the helium GFIS. However neon does differ from the helium GFIS in two significant ways: neon ions have high sputtering yields (e.g. 1 Si atom per incident ion at 20 keV); and have relatively shallow implant depth (e.g. 46 nm in silicon at 20 keV). Both of these are limiting factors for helium in many nanomachining applications. In this paper we will present both simulation and experimental results of the neon GFIS used for imaging and nanomachining applications.

Livengood, Richard H.; Tan, Shida; Hallstein, Roy; Notte, John; McVey, Shawn; Faridur Rahman, F. H. M.

2011-07-01

58

Biochemical Properties of Squid Axon Membranes.  

National Technical Information Service (NTIS)

Biochemical and physiological studies in the giant axons of the Chilean squid Dosidicus Gigas were carried out in order to correlate metabolic dependent sodium transport and the enzymic profile of nerve membranes. Membrane fractions were isolated from the...

M. Canessa F. Vargas C. Hidalgo V. Riveros I. Zamudio

1966-01-01

59

Fly School  

NSDL National Science Digital Library

The processes used by humans to perform certain forms of learning are the same as those in many other species. Even the humble fruit fly is an excellent model of how genes affect our ability to learn.

2009-04-14

60

Flying Cars  

NASA Technical Reports Server (NTRS)

Flying cars have nearly mythical appeal to nonpilots, a group that includes almost the whole human race. The appeal resides in the perceived utility of flying cars, vehicles that offer portal-to-portal transportation, yet break the bonds of road and traffic and travel freely through the sky at the drivers will. Part of the appeal is an assumption that flying cars can be as easy to fly as to drive. Flying cars have been part of the dream of aviation since the dawn of powered flight. Glenn Curtiss built, displayed, and maybe even flew a flying car in 1917, the Curtiss Autoplane. Many roadable airplanes were built in the 1930's, like the Waterman Arrowbile and the Fulton Airphibian. Two flying cars came close to production in the early 1950's. Ted Hall built a series of flying cars culminating in the Convaircar, sponsored by Consolidated Vultee, General Motors, and Hertz. Molt Taylor built and certified his Aerocar, and Ford came close to producing them. Three Aerocars are still flyable, two in museums in Seattle and Oshkosh, and the third owned and flown by Ed Sweeny. Flying cars do have problems, which so far have prevented commercial success. An obvious problem is complexity of the vehicle, the infrastructure, or both. Another is the difficulty of matching low power for normal driving with high power in flight. An automobile uses only about 20 hp at traffic speeds, while a personal airplane needs about 160 hp at speeds typical of flight. Many automobile engines can deliver 160 hp, but not for very long. A more subtle issue involves the drag of automobiles and airplanes. A good personal airplane can fly 30 miles per gallon of fuel at 200 mph. A good sports car would need 660 hp at the same speed and would travel only 3 miles per gallon. The difference is drag area, about 4.5 sq ft for the automobile and 1.4 sq ft for the airplane. A flying car better have the drag area of the airplane, not the car!

Crow, Steven

1996-01-01

61

A Closed Neon Liquefier System for Testing Superconducting Devices  

Microsoft Academic Search

A Neon liquefier system has been developed by Southampton University (UK) and EDISON (Italy) with the aim to provide a facility for testing HTS superconducting devices using Magnesium Diboride materials, in the range 25-30K. The system consists of a liquid Neon cryostat coupled to a two stages cryocooler and a recovery system. The first stage of the cryocooler is connected

M. Bianchetti; M. K. Al-Mosawi; Y. Yang; C. Beduz; G. Giunchi

2006-01-01

62

Scattering of electrons from neon atoms  

NASA Technical Reports Server (NTRS)

Scattering of electrons from neon atoms is investigated by the polarized-orbital method. The perturbed orbitals calculated with use of the Sternheimer approximation lead to the polarizability 2.803 a(0)-cube in fairly good agreement with the experimental value 2.66 a(0)-cube. Phase shifts for various partial waves are calculated in the exchange, exchange-adiabatic, and polarized-orbital approximations. They are compared with the previous results. The calculated elastic differential, total, and momentum-transfer cross sections are compared with the experimental results. The polarized-orbital approximation yields results which show general improvement over the exchange-adiabatic approximation.

Dasgupta, A.; Bhatia, A. K.

1984-01-01

63

Multipole polarizabilities and London dispersion forces between neon and helium atoms using double perturbation theory  

Microsoft Academic Search

Using an interchange theorem the polarizability of the neon atom at imaginary frequencies is calculated correct to first order in electron correlation. These results are then used to evaluate the long-range dispersion interactions between two neon atoms and between neon and helium atoms. For neon-neon interactions we find ?(5.308 ? R6) [1+(11.53 ? R2) + (189.5 ? R4)], while for

J. T. Broussard; Neil R. Kestner

1973-01-01

64

Analysis of a Digital SQUID Magnetometer Utilizing a Direct Coupled DC SQUID for Improved Magnetic Field Resolution  

Microsoft Academic Search

Magnetometers utilizing digital SQUIDs are good candidates for high sensitive measurements of rapidly varying magnetic fields in a wide range. The association of its very large dynamic range together with the very high field resolution of an analog SQUID leads to new generation of SQUID sensors. This paper describes a hybrid magnetometer system, which is designed for applications in unshielded

Torsten Reich; Thomas Ortlepp; F. Hermann Uhlmann

2007-01-01

65

Time Flies  

NSDL National Science Digital Library

This news article from the National Physical Laboratory describes how physicists updated an experimental test of special and general relativity by flying atomic clocks around the world. The article includes an image of the data, clearly illustrating the result, and also a photo of the traveling clocks.

2011-10-15

66

Pop Fly  

NSDL National Science Digital Library

In this design challenge activity, learners invent a way to send a Ping-Pong ball flying high enough to catch it - like football with a twist! Learners use paint stirrers, a wooden spool, tape, and their feet to launch the ball. This fun hands-on activity introduces learners to the design process while exploring levers.

Wgbh

2010-01-01

67

Comprehensive Testing of a Neon Cryogenic Capillary Pumped Loop  

NASA Technical Reports Server (NTRS)

This paper describes a comprehensive test program of a cryogenic capillary pumped loop (CCPL) using neon as the working fluid in the temperature range between 30 K and 40 K. The test article was originally designed to be used with nitrogen in the 70 K to 100 K temperature range, and was refurbished for testing with neon. Tests performed included start up from a supercritical state, power cycle, sink temperature cycle, heat transport limit, low power limit, reservoir set point change and long duration operation. The neon CCPL has demonstrated excellent performance under various conditions.

Kobel, Mark C.; Ku, Jentung; Obenschain, Arthur F. (Technical Monitor)

2001-01-01

68

Microwave oscillators based on dc SQUIDs  

NASA Astrophysics Data System (ADS)

We have fabricated lumped-element microwave oscillators consisting of a dc SQUID with submicron Al-AlOx-Al junctions shunted with a capacitor formed from superconducting layers. These circuits resonate in the range of several GHz. Adjusting the current through on-chip bias lines changes the Josephson inductance of the SQUID junctions, thus varying the resonance frequency. We discuss the prospects for time-domain monitoring of the ring-down oscillations following a bias current pulse in these circuits. The discrimination of ring-down signals for different flux bias forms the basis for employing these devices in a possible new readout scheme for superconducting flux qubits.

Bhupathi, P.; Defeo, M. P.; Song, C.; Plourde, B. L. T.

2010-03-01

69

Magnetism in SQUIDs at millikelvin temperatures.  

PubMed

We have characterized the temperature dependence of the flux threading dc SQUIDs cooled to millikelvin temperatures. The flux increases as 1/T as temperature is lowered; moreover, the flux change is proportional to the density of trapped vortices. The data are compatible with the thermal polarization of surface spins in the trapped fields of the vortices. In the absence of trapped flux, we observe evidence of spin-glass freezing at low temperature. These results suggest an explanation for the universal 1/f flux noise in SQUIDs and superconducting qubits. PMID:18643451

Sendelbach, S; Hover, D; Kittel, A; Mück, M; Martinis, John M; McDermott, R

2008-06-01

70

Design of a hysteretic SQUID as the readout for a dc SQUID  

SciTech Connect

This paper present a design for an optimal hysteretic SQUID readout circuit for a DC SQUID, thus eliminating the need for bulky output transformers or resonance matching circuits. The hysteretic readout system, which is based in part on standard sampling theory, is compared to another similar system and shown to be superior in terms of slew rate and immunity of electromagnetic interference. The circuit will be useful in optimizing the performance of biomagnetic systems.

Gershenson, M. (Naval Coastal Systems Center, Panama City, FL (United States))

1991-03-01

71

8. DETAIL OF NORTHEAST ELEVATION SHOWING NEON TWA SIGN AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. DETAIL OF NORTHEAST ELEVATION SHOWING NEON TWA SIGN AND ROOF MASTS. LOOKING SOUTHWEST. - TWA Maintenance Hangar, South side of Tinicum Island Road, Philadelphia International Airport, Philadelphia, Philadelphia County, PA

72

NEON's Mobile Deployment Platform: Seeking Input on a Community Resource  

NASA Astrophysics Data System (ADS)

We seek input from the AGU community on the National Ecological Observatory Network's (NEON) PI and agency requestable Mobile Deployment Platform (MDP). The NEON MDPs will provide the means to observe stochastic or spatially important events, gradients, or quantities that cannot be reliably observed using fixed location sampling (e.g. fires and floods). Due to the transient temporal and spatial nature of such events, the MDPs will be designed to accommodate rapid deployment for time periods up to ~ 1 year. Broadly, the MDPs will be comprised of infrastructure and instrumentation capable of functioning individually or in conjunction with one another to support observations of ecological change, as well as education, training and outreach. We aim to glean input on selecting infrastructure and instrumentation relevant to meeting the needs of NEON and the broader scientific community. This poster will be formatted to allow for direct commentary on the MDP. Comments will be compiled and made available on the NEON website for further discussion.

SanClements, M.; Loescher, H. W.

2012-12-01

73

A determination of the neon isotopic composition of the mantle  

Microsoft Academic Search

From the analysis of mantle-derived samples, several authors have proposed that the neon isotopic composition of the mantle was close to solar (21{Ne}\\/22{Ne}=13.8) (Marty, 1989, Honda et al., 1991), with additional nucleogenic 21{Ne} and possibly 22{Ne} due to Wethrlill reactions. This interpretation has been challenged by Trieloff et al. (2000; 2002) who claimed that the primitive mantle neon is different

R. Yokochi; B. Marty

2003-01-01

74

3 kHz SQUID Receiver Development.  

National Technical Information Service (NTIS)

A model was designed and tested for a 3 kHz receiver using a superconducting antenna circuit and a SQUID (Superconducting QUantum Interference Device) amplifier. Q factors as high as 6400 have been demonstrated for the resonant antenna, giving it an extre...

M. B. Simmonds W. A. Fertig R. P. Giffard

1978-01-01

75

Squid Dissection: From Pen to Ink.  

ERIC Educational Resources Information Center

Introduces students to dissection, which is an important part of scientific discovery. Students not only gain an understanding of the anatomy of a squid, but also develop a sense of responsibility and respect for the animal that they are using as a learning tool. (Author/SOE)

Brown, Cindy; Kisiel, Jim

2003-01-01

76

One Period of Exploration with the Squid.  

ERIC Educational Resources Information Center

Presents a lab that can be offered after students have learned the basic anatomy and physiology of the various phyla, the primary objective of which is to explore and apply their acquired knowledge to a new situation. Involves exploring the anatomy and life-style of the squid. (JRH)

Bradley, James V.; Ng, Andrew

1997-01-01

77

Multichannel SQUID systems for brain research  

SciTech Connect

This paper reviews basis principles of magnetoencephalography (MEG) and neuromagnetic instrumentation. The authors' 24-channel system, based on planar gradiometer coils and dc-SQUIDs, is then described. Finally, recent MEG-experiments on human somatotopy and focal epilepsy, carried out in the authors' laboratory, are presented.

Ahonen, A.I.; Hamalainen, M.S.; Kajola, M.J.; Knuutila, J.E.F.; Lounasmaa, O.V.; Simola, J.T.; Vilkman, V.A. (Helsinki Univ. of Technology, Espoo (Finland). Low Temperature Lab.); Tesche, C.D. (International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center)

1991-03-01

78

Fly Ash  

Microsoft Academic Search

\\u000a  The fly ash, also known as pulverised fuel ash, is produced from burning pulverized coal in electric power generating plants. During\\u000a combustion, mineral impurities in the coal (clay, feldspar, quartz, and shale) fuse in suspension and float out of the combustion\\u000a chamber along with exhaust gases. As the fused material rises, it cools and solidifies into spherical glassy particles called

Rafat Siddique; Mohammad Iqbal Khan

79

Interactive Fly  

NSDL National Science Digital Library

This site is award-winning and comprehensive. It thoroughly discusses genes, tissues, biochemical paths, and developmental processes in the fruit fly, Drosophila. Its gene index identifies genes with their functions, maternal and zygotically transcribed genes, genes important to behavior and genes in conserved pathways. Its tissue and organ development section shows stages and an atlas, as well as genes and processes in gastrulation, histogenesis, morphogenesis, organogenesis, imaginal discs, adult formation, oogenesis and spermatogenesis.

PhD Thomas B Brody (NIH Laboratory of Neurochemistry)

2005-09-13

80

Acceleration of neon pellets to high speeds for fusion applications  

SciTech Connect

The injection of impurity pellets into the plasmas of tokamak fusion reactors has been proposed as a technique to lessen the deleterious effects of plasma disruptions. Equipment and techniques that were previously developed for pneumatic hydrogen pellet injection systems and used for plasma fueling applications were employed for a limited experimental study with neon pellets. Isotopic hydrogen pellets doped with neon have previously been used for injection into fusion plasmas to study impurity particle transport, and pure neon pellets are applicable for disruption studies. Using a repeating pneumatic injector in the laboratory, it was found that the formation and acceleration of 2.7-mm-diam neon pellets were relatively straightforward; reliable operation was demonstrated with both a single- and a two-stage light gas gun, including velocities of {approximately}700 m/s with a single-stage injector and up to 1740 m/s with a two-stage injector. Based on the operating sequences and successful tests demonstrated in the laboratory experiments, a three-barrel repeating pneumatic injector installed on the DIII-D tokamak was equipped with the necessary components for neon operation and has been used in initial disruption experiments with 1.8-mm-diam neon pellets. {copyright} {ital 1996 American Institute of Physics.}

Combs, S.K.; Love, T.L.; Jernigan, T.C.; Milora, S.L. [Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831-8071 (United States)] [Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831-8071 (United States); Frattolillo, A.; Migliori, S. [ENEA, Centro Ricerche Energia Frascati, Frascati, Rome (Italy)] [ENEA, Centro Ricerche Energia Frascati, Frascati, Rome (Italy)

1996-03-01

81

A neon-E-rich phase in the Orgueil carbonaceous chondrite  

NASA Technical Reports Server (NTRS)

Attention is given to a procedure for separating a silicate fraction which contains large amounts of neon-E from the carbonaceous chondrite Orgueil. In this fraction a 20Ne/22Ne ratio of 4.56 is measured. The obtained data support the hypothesis that neon-E might be associated with interstellar dust grains of the type not fully homogenized with the solar system and which retain some of their trapped neon. Neon results in a three-isotope diagram are presented.

Eberhardt, P.

1974-01-01

82

Electron Impact Excitation and Ionization of Neon  

NASA Astrophysics Data System (ADS)

We have further developed the B-Spline R-matrix (BSR) code [1] to allow for a large number of pseudo-states in the close-coupling expansion. In the present work, the BSRMPS approach [2] was employed to perform semi-relativistic (Breit-Pauli) close-coupling calculations for elastic scattering, excitation, and ionization of neon from both the ground state and the metastable excited states. Coupling to the ionization continuum through the pseudo-states is important for low-energy elastic scattering (to represent polarizability effects), for excitation in the ``intermediate'' energy regime of about 1-5 times the ionization potential, and to allow for the calculation of ionization processes by transforming the results obtained for excitation of the positive-energy pseudo-states. The current results represent a significant extension of our earlier near-threshold work [3] and previous non-relativistic RMPS calculations [4,5].[4pt] [1] O. Zatsarinny, Comp. Phys. Commun. 174 (2006) 273.[0pt] [2] O. Zatsarinny and K. Bartschat, Phys. Rev. Lett. 107 (2011) 023203.[0pt] [3] O. Zatsarinny and K. Bartschat, J. Phys. B 37 (2004) 2173.[0pt] [4] C. P. Ballance and D. C. Griffin, J. Phys. B 37 (2004) 2943.[0pt] [5] C. P. Ballance et al., J. Phys. B 37 (2004) 4779.

Zatsarinny, Oleg; Bartschat, Klaus

2012-10-01

83

Coupled Serial and Parallel Non-uniform SQUIDs  

NASA Astrophysics Data System (ADS)

In this work we numerical model series and parallel non-uniform superconducting quantum interference device (SQUID) array. Previous work has shown that series SQUID array constructed with a random distribution of loop sizes, (i.e. different areas for each SQUID loop) there exists a unique `anti-peak' at the zero magnetic field for the voltage versus applied magnetic field (V-B). Similar results extend to a parallel SQUID array where the difference lies in the arrangement of the Josephson junctions. Other system parameter such as bias current, the number of loops, and mutual inductances are varied to demonstrate the change in dynamic range and linearity of the V-B response. Application of the SQUID array as a low noise amplifier (LNA) would increase link margins and affect the entire communication system. For unmanned aerial vehicles (UAVs), size, weight and power are limited, the SQUID array would allow use of practical `electrically small' antennas that provide acceptable gain.

Longhini, Patrick; Berggren, Susan; Palacios, Antonio; de Escobar, Anna Leese; in, Visarath

2011-04-01

84

Biomagnetism using SQUIDs: status and perspectives  

NASA Astrophysics Data System (ADS)

Biomagnetism involves the measurement and analysis of very weak local magnetic fields of living organisms and various organs in humans. Such fields can be of physiological origin or due to magnetic impurities or markers. This paper reviews existing and prospective applications of biomagnetism in clinical research and medical diagnostics. Currently, such applications require sensitive magnetic SQUID sensors and amplifiers. The practicality of biomagnetic methods depends especially on techniques for suppressing the dominant environmental electromagnetic noise, and on suitable nearly real-time data processing and interpretation methods. Of the many biomagnetic methods and applications, only the functional studies of the human brain (magnetoencephalography) and liver susceptometry are in clinical use, while functional diagnostics of the human heart (magnetocardiography) approaches the threshold of clinical acceptance. Particularly promising for the future is the ongoing research into low-field magnetic resonance anatomical imaging using SQUIDs.

Sternickel, Karsten; Braginski, Alex I.

2006-03-01

85

Protecting SQUID metamaterials against stray magnetic fields  

NASA Astrophysics Data System (ADS)

Using superconducting quantum interference devices (SQUIDs) as the basic, low-loss elements of thin-film metamaterials has one main advantage: their resonance frequency is easily tunable by applying a weak magnetic field. The downside, however, is a strong sensitivity to stray and inhomogeneous magnetic fields. In this work, we demonstrate that even small magnetic fields from electronic components destroy the collective, resonant behaviour of the SQUID metamaterial. We also show how the effect of these fields can be minimized. As a first step, magnetic shielding decreases any initially present fields, including the earth’s magnetic field. However, further measures such as improvements in the sample geometry have to be taken to avoid the trapping of Abrikosov vortices.

Butz, S.; Jung, P.; Filippenko, L. V.; Koshelets, V. P.; Ustinov, A. V.

2013-09-01

86

Investigation of noise sources in SQUID electronics  

SciTech Connect

The performance of SQUID-based electronics outside a laboratory-controlled environment may be degraded from that found in laboratory operation. Investigations on superconducting tubes, wires, and sheets have been conducted to identify contributions to such noise. Results have been obtained for bulk and thin film samples utilizing both the conventional low temperature materials, as well as the new high temperature oxide materials. Experiments have been conducted to quantify flux redistribution and flux motion in superconducting samples subjected to temperature changes, temperature gradients, and magnetic field gradients. These investigations have been conducted at magnetic fields typical of many SQUID applications, with field intensities much smaller than the critical values H/sub cl/. Penetration depth effects, flux pinning effects, and flux motion effects have been observed. The various types of experiments conducted along with specific results are described.

Clem, T.R.; Goldstein, M.J.; Purpura, J.W.; Allen, L.H.; Claassen, J.H.; Gubser, D.U.; Wolf, S.A.

1989-03-01

87

SQUID applications to geophysics. Final report  

SciTech Connect

No alternatives to liquid-helium cryostats for SQUID geomagnetic measurements are presently available, but micro-miniature Joule-Thomson and low-power nonmagnetic Stirling cryocoolers are being developed for this and similar purposes. With increasing interest and experimental work on the subject during the past year or two, it is likely that demonstrations of feasibility will occur in the moderately near future, and perhaps even a suitable commercial cryocooler in the next few years.

Zimmerman, J.E.; Weinstock, H.; Overton, W.C.

1981-01-01

88

SQUID-based high-resolution thermometer  

NASA Astrophysics Data System (ADS)

High-resolution thermometers (HRTs) based on the detection of magnetization changes of a magnetic material using very sensitive superconducting quantum interference device (SQUID) have routinely achieved temperature resolution of 0.1 nK/ Hz at temperatures below 4 K in several laboratories. The resolution of these thermometers has reached the fundamental limit imposed by thermodynamic fluctuations. The principle of operation as well as the theory of the noise are presented. Some recent discoveries using HRT are discussed.

Chui, Talso C. P.

2001-05-01

89

Digital filter design approach for SQUID gradiometers  

SciTech Connect

A review of the traditional method for designing gradiometers is made. A nonrecursive digital filter model for the gradiometer is presented, giving a new set of parameters for the gradiometer identification. Some designs are analyzed using the proposed set. As an example, a true differentiator is designed to be used as the SQUID input coil. It is shown that the differentiator has the same noise rejection as the conventional gradiometer but provides more signal sensitivity.

Bruno, A.C.; Ribeiro, P.C.

1988-04-15

90

Odorant Responsiveness of Squid Olfactory Receptor Neurons  

PubMed Central

In the olfactory organ of the squid, Lolliguncula brevis there are five morphological types of olfactory receptor neurons (ORNs). Previous work to characterize odor sensitivity of squid ORNs was performed on only two of the five types in dissociated primary cell cultures. Here we sought to establish the odorant responsiveness of all five types. We exposed live squid or intact olfactory organs to excitatory odors plus the activity marker, agmatine (AGB), an arginine derivative that enters cells through non-selective cation channels. An antibody against AGB was used to identify odorant-activated neurons. We were able to determine the ORN types of AGB-labeled cells based on their location in the epithelium, morphology and immunolabeling by a set of metabolites: arginine, aspartate, glutamate, glycine and glutathione. Of 389 neurons identified from metabolite-labeled tissue, 3% were type 1, 32% type 2, 33% type 3, 15% type 4 and 17% type 5. Each ORN type had different odorant specificity with type 3 cells showing the highest percentages of odorant-stimulated AGB labeling. Type 1 cells were rare and none of the identified type 1 cells responded to the tested odorants, which included glutamate, alanine and AGB. Glutamate is a behaviorally attractive odorant and elicited AGB labeling in types 2 and 3. Glutamate-activated AGB labeling was significantly reduced in the presence of the adenylate cyclase inhibitor, SQ22536 (80 ?M). These data suggest that the five ORN types differ in their relative abundance and odor responsiveness and that the adenylate cyclase pathway is involved in squid olfactory transduction.

Mobley, Arie Sitthichai; Michel, William C.; Lucero, Mary T.

2008-01-01

91

Development of airborne remote sensing instrumentations for NEON  

NASA Astrophysics Data System (ADS)

Airborne remote sensing plays a critical role in the scaling strategy underpinning the National Ecological Observatory Network (NEON) design. Airborne spectroscopy and waveform LiDAR will quantify plant species type and function, and vegetation structure and heterogeneity at the scale of individual shrubs and larger plants (1-3 meters) over hundreds of square kilometers. Panchromatic photography at better than 30 cm resolution will retrieve fine-scale information regarding land use, roads, impervious surfaces, and built structures. NEON will build three airborne systems to allow for routine coverage of NEON sites (60 sites nationally) and the capacity to respond to investigator requests for specific projects. The system design achieves a balance between performance, and development cost and risk. The approach takes full advantage of existing commercial airborne LiDAR and camera components. However, requirements for the spectrometer represent a significant advancement in technology. A pushbroom imaging spectrometer design is being proposed to simultaneously achieve high spatial, spectral and signal-to-noise ratio and a high degree of uniformity in response across wavelength and a wide field of view. To reduce risk during NEON construction, a spectrometer design verification unit is under development by the Jet Propulsion Laboratory to demonstrate that the design and component technologies meet operational and performance requirements. This paper presents an overview of system design, key requirements and development status of the NEON airborne instrumentation.

Johnson, Brian R.; Kampe, Thomas U.; Kuester, Michele

2010-08-01

92

Low field SQUID MRI devices, components and methods  

NASA Technical Reports Server (NTRS)

Low field SQUID MRI devices, components and methods are disclosed. They include a portable low field (SQUID)-based MRI instrument and a portable low field SQUID-based MRI system to be operated under a bed where a subject is adapted to be located. Also disclosed is a method of distributing wires on an image encoding coil system adapted to be used with an NMR or MRI device for analyzing a sample or subject and a second order superconducting gradiometer adapted to be used with a low field SQUID-based MRI device as a sensing component for an MRI signal related to a subject or sample.

Penanen, Konstantin I. (Inventor); Eom, Byeong H (Inventor); Hahn, Inseob (Inventor)

2010-01-01

93

Recent experimental work on point-contact dc squid  

NASA Astrophysics Data System (ADS)

A toroidal point-contact dc SQUID has been successfully operated. A large input coil with L i = 64 ?H was coupled with ?2 = 0.34 without creasing the rf inductance of the dc SQUID by means of “capacitive shunt.” The observed values of I cR = 200 ?V, | {? V}/{??}| ? 400? {V}/{?}o and {R}/{Lrf}? 3 x 10 11s-1 are close to those required for quantum-limited limited sensitivity. Noise characteristics of this SQUID are being investigated using an rf SQUID readout.

Castellano, M. G.; Paik, H. J.

1981-08-01

94

Low field SQUID MRI devices, components and methods  

NASA Technical Reports Server (NTRS)

Low field SQUID MRI devices, components and methods are disclosed. They include a portable low field (SQUID)-based MRI instrument and a portable low field SQUID-based MRI system to be operated under a bed where a subject is adapted to be located. Also disclosed is a method of distributing wires on an image encoding coil system adapted to be used with an NMR or MRI device for analyzing a sample or subject and a second order superconducting gradiometer adapted to be used with a low field SQUID-based MRI device as a sensing component for an MRI signal related to a subject or sample.

Penanen, Konstantin I. (Inventor); Eom, Byeong H. (Inventor); Hahn, Inseob (Inventor)

2011-01-01

95

Fly Ash and Fly Ash Concrete.  

National Technical Information Service (NTIS)

Fly ash is a residue that results from the combustion of ground or powdered coal. Historically, fly ash has been referred to as a pozzolan and is used to reduce the amount of portland cement in concrete. However, in many Western States fly ashes have ceme...

E. R. Dunstan

1984-01-01

96

NEON INSIGHTS FROM OLD SOLAR X-RAYS: A PLASMA TEMPERATURE DEPENDENCE OF THE CORONAL NEON CONTENT  

SciTech Connect

An analysis using modern atomic data of fluxes culled from the literature for O VIII and Ne IX lines observed in solar active regions by the P78 and Solar Maximum Mission satellites confirms that the coronal Ne/O abundance ratio varies by a factor of two or more, and finds an increase in Ne/O with increasing active region plasma temperature. The latter is reminiscent of evidence for increasing Ne/O with stellar activity in low-activity coronae that reaches a 'neon saturation' in moderately active stars at approximately twice the historically accepted solar value of about 0.15 by number. We argue that neon saturation represents the underlying stellar photospheric compositions, and that low-activity coronae, including that of the Sun, are generally depleted in neon. The implication would be that the solar Ne/O abundance ratio should be revised upward by a factor of about two to n(Ne)/n(O) {approx} 0.3. Diverse observations of neon in the local cosmos provide some support for such a revision. Neon would still be of some relevance for reconciling helioseismology with solar models computed using recently advocated chemical mixtures with lower metal content.

Drake, Jeremy J., E-mail: jdrake@cfa.harvard.edu [Smithsonian Astrophysical Observatory, MS-3, 60 Garden Street, Cambridge, MA 02138 (United States)

2011-12-10

97

Helium and neon isotopes in deep Pacific Ocean sediments  

NASA Technical Reports Server (NTRS)

Helium and neon concentration measurements, along with isotope ratio determinations, have been made for particles collected in the deep Pacific with a magnetic sled, and they are believed to be of extraterrestrial origin. Analyses were made for samples consisting of composites of many extremely fine particles and for several individual particles large enough to contain sufficient gas for analysis but small enough to escape melting in their passage through the atmosphere. Step-heating was employed to extract the gas. Cosmic-ray spallation products or solar-wind helium and neon, if present, were not abundant enough to account for the isotopic compositions measured. In the case of the samples of magnetic fines, the low temperature extractions provided elemental and isotopic ratios in the general range found for the primordial gas in carbonaceous chondrites and gas-rich meteorites. The isotopic ratios found in the high temperature extractions suggest the presence of solar-flare helium and neon.

Nier, A. O.; Schlutter, D. J.; Brownlee, D. E.

1990-01-01

98

Fast Imaging of Intact and Shattered Cryogenic Neon Pellets  

SciTech Connect

Compact condensed-matter injection technologies are increasingly used in magnetic fusion. One recent application is in disruption mitigation. An imaging system with less-than-100- m- and sub- s-resolution is described and used to characterize intact and shattered cryogenic neon pellets. Shattered pellets contain fine particles ranging from tens of m to about 7 mm. Time-of-flight analyses indicate that pellets could slow down if hitting the wall of the guide tube. Fast high-resolution imaging systems are thus useful to neon and other condensed-matter injector development.

Wang, Zhehui [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Combs, Stephen Kirk [ORNL] [ORNL; Baylor, Larry R [ORNL] [ORNL; Foust, Charles R [ORNL] [ORNL; Lyttle, Mark S [ORNL] [ORNL; Meitner, Steven J [ORNL] [ORNL; Rasmussen, David A [ORNL] [ORNL

2014-01-01

99

The isotopic composition of solar flare accelerated neon  

NASA Technical Reports Server (NTRS)

The individual isotopes of neon in energetic solar-flare particles have been clearly resolved with a rms mass resolution of 0.20 amu. The ratios found are Ne-20/Ne-22 = 7.6 (+2.0, -1.8) and Ne-21/Ne-22 of no more than about 0.11 in the 11-26 MeV per nucleon interval. This isotopic composition is essentially the same as that of meteoritic planetary neon-A and is significantly different from that of the solar wind.

Mewaldt, R. A.; Spalding, J. D.; Stone, E. C.; Vogt, R. E.

1979-01-01

100

Fly on the Ceiling  

NSDL National Science Digital Library

In this math lesson, learners play two different games to help them understand coordinates. First, learners read the book, "The Fly on the Ceiling," by Julie Glass. Then, learners play "Fly Tic-Tac-Toe," a game similar to tic-tac-toe but with coordinates, and "Swat the Flies," a game similar to Battleship but with flies. Each game requires two players.

Lessonplans, Utah

2012-10-30

101

Neon diffusion kinetics in olivine, pyroxene and feldspar: Retentivity of cosmogenic and nucleogenic neon  

NASA Astrophysics Data System (ADS)

We performed stepwise degassing experiments by heating single crystals of neutron- or proton-irradiated olivine, pyroxene and feldspar to study diffusion kinetics of neon. This is important in evaluating the utility of these minerals for cosmogenic 21Ne measurements and, potentially, for Ne thermochronometry. Degassing patterns are only partially explained by simple Arrhenius relationships; most samples do not exhibit a precisely-determined activation energy in an individual diffusion domain. Regardless, we find clear differences in diffusion kinetics among these minerals. Based on sub-selected data, our estimates for neon diffusion kinetics (activation energy Ea and pre-exponential factor Do, assuming the analyzed fragments approximate the diffusion domain) in each mineral are as follows: for the feldspars, Ea ranges from ˜65 to 115 kJ/mol and Do from 3.9 × 10-3 to 7.1 × 102 cm2s-1; for the pyroxenes, Ea ranges from ˜292 to 480 kJ/mol and Do from 1.6 × 102 to 2.9 × 1011 cm2s-1; for the olivines, Ea ranges from ˜360 to 370 kJ/mol and Do from 1.5 × 106 to 5.0 × 106 cm2s-1. Differences in these parameters are broadly consistent with the expected effect of structural differences between feldspar, and olivine and pyroxene. These results indicate that cosmogenic 21Ne will be quantitatively retained within olivine and pyroxene at Earth surface temperatures over geological timescales. The diffusion kinetics for feldspars, on the other hand, predicts that 21Ne retention at Earth surface temperatures will vary significantly with domain size, crystal microtexture, surface temperature, and exposure duration. Quantitative retention is expected only in favorable conditions. This conclusion is reinforced by additional measurements of cosmogenic 21Ne in coexisting quartz and feldspar from naturally irradiated surface samples; sanidine from a variety of rhyolitic ignimbrites exhibits quantitative retention, whereas alkali-feldspar from several granites does not.

Gourbet, Loraine; Shuster, David L.; Balco, Greg; Cassata, William S.; Renne, Paul R.; Rood, Dylan

2012-06-01

102

Broadband SQUID NMR with Room-Temperature Samples  

Microsoft Academic Search

Superconducting quantum interference devices (SQUIDs) are the most sensitive detectors of magnetic fields. We have used an untuned broadband SQUID detector to detect transverse nuclear magnetic-resonance signals from samples of mineral oil, salt water, and animal tissue at room temperature. Proton NMR signals have been detected from about 20 to 450 kHz. We have also detected fluorine, sodium, and possibly

S. Kumar; B. D. Thorson; W. F. Avrin

1995-01-01

103

Modelling environmental influences on squid life history, distribution, and abundance  

Microsoft Academic Search

Following Caddy and Gulland's (1983) classification, squid populations can be described as displaying irregular or spasmodic abundance fluctuations, as opposed to steady or cyclical patterns. Squid are short-lived, fast growing marine animals, thought to be especially sensitive to environmental influences (Coelho, 1985). Because generations are essentially non-overlapping, modelling of population dynamics reduces to predicting recruitment success (Caddy, 1983; Pierce and

Graham J. Pierce; M. Begoña Santos; Colin D. MacLeod; Jianjun Wang; Vasilis Valavanis; Alain F. Zuur

104

Read-out electronics for DC squid magnetic measurements  

DOEpatents

Read-out electronics for DC SQUID sensor systems, the read-out electronics incorporating low Johnson noise radio-frequency flux-locked loop circuitry and digital signal processing algorithms in order to improve upon the prior art by a factor of at least ten, thereby alleviating problems caused by magnetic interference when operating DC SQUID sensor systems in magnetically unshielded environments.

Ganther, Jr., Kenneth R. (Olathe, KS); Snapp, Lowell D. (Independence, MO)

2002-01-01

105

SQUID magnetometry from nanometer to centimeter length scales  

SciTech Connect

The development of Superconducting QUantum Interference Device (SQUID)-based magnetometer for two applications, in vivo prepolarized, ultra-low field MRI of humans and dispersive readout of SQUIDs for micro- and nano-scale magnetometery, are the focus of this thesis.

Hatridge, Michael J.

2010-06-28

106

A modular 31-channel SQUID system for biomagnetic measurements  

Microsoft Academic Search

A modular multichannel superconducting quantum interference device (SQUID) system, in which every channel can be optimized or replaced individually, was further improved. The number of channels was increased to 31. The noise level is better than 10 fT\\/?Hz. A novel way of RF shielding using conductive paint avoids degradation of the SQUID characteristics due to RF interference without introducing significant

O. Dossel; B. David; M. Fuchs; J. Kruger; K.-M. Ludeke; H.-A. Wischmann

1993-01-01

107

Detection of subsurface flaws using SQUID eddy current technique  

Microsoft Academic Search

Subsurface flaws in electrically conducting components are not easy to detect by conventional eddy current techniques because the skin depth (delta) decreases at high frequencies, while the signal decreases at low frequencies. However, SQUID magnetometers are capable of measuring dc and low frequency magnetic fields, and have been used for imaging current distributions. We have now extended SQUID NDE by

Yu P. Ma; John P. Wikswo

1993-01-01

108

Heritability and fitness-related consequences of squid personality traits  

Microsoft Academic Search

Dumpling squid, Euprymna tasmanica, show consistent individual differences in behaviour that can be classified according to indices reflecting shy-bold, activity and reactivity responses. Using crosses of wild-caught single males to multiple females with known behavioural phenotypes, this study estimated patterns of additive genetic and residual variance in these behavioural traits from offspring of squid in two contexts, a threat (antipredator)

D. L. SINN; L. A. APIOLAZA; N. A. MOLTSCHANIWSKYJ

2006-01-01

109

Virtual fly  

NSDL National Science Digital Library

3D virtual image of a blow fly (Family Calliphoridae). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the ÃÂHelpÃÂ page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

0002-11-30

110

Elemental abundances of flaring solar plasma - Enhanced neon and sulfur  

NASA Technical Reports Server (NTRS)

Elemental abundances of two flares observed with the SMM Flat Crystal Spectrometer are compared and contrasted. The first had a gradual rise and a slow decay, while the second was much more impulsive. Simultaneous spectra of seven bright soft X-ray resonance lines provide information over a broad temperature range and are available throughout both flares, making these events unique in the SMM data base. For the first flare, the plasma seemed to be characterized by coronal abundances but, for the second, the plasma composition could not be coronal, photospheric, or a linear combination of both. A good differential emission measure fit required enhanced neon such that Ne/O = 0.32 +/- 0.02, a value which is inconsistent with the current models of coronal abundances based on the elemental first-ionization potential. Similar values of enhanced neon are found for flaring plasma observed by the SMM gamma-ray spectrometer, in (He-3)-rich solar energetic particle events, and in the decay phase of several long duration soft X-ray events. Sulfur is also enhanced in the impulsive flare, but not as dramatically as neon. These events are compared with two models which attempt to explain the enhanced values of neon and sulfur.

Schmelz, J. T.

1993-01-01

111

Neon and CO2 adsorption on open carbon nanohorns.  

PubMed

We present the results of a thermodynamics and kinetics study of the adsorption of neon and carbon dioxide on aggregates of chemically opened carbon nanohorns. Both the equilibrium adsorption characteristics, as well as the dependence of the kinetic behavior on sorbent loading, are different for these two adsorbates. For neon the adsorption isotherms display two steps before reaching the saturated vapor pressure, corresponding to adsorption on strong and on weak binding sites; the isosteric heat of adsorption is a decreasing function of sorbent loading (this quantity varies by about a factor of 2 on the range of loadings studied), and the speed of the adsorption kinetics increases with increasing loading. By contrast, for carbon dioxide there are no substeps in the adsorption isotherms; the isosteric heat is a nonmonotonic function of loading, the value of the isosteric heat never differs from the bulk heat of sublimation by more than 15%, and the kinetic behavior is opposite to that of neon, with equilibration times increasing for higher sorbent loadings. We explain the difference in the equilibrium properties observed for neon and carbon dioxide in terms of differences in the relative strengths of adsorbate-adsorbate to adsorbate-sorbent interaction for these species. PMID:23802764

Krungleviciute, Vaiva; Ziegler, Carl A; Banjara, Shree R; Yudasaka, Masako; Iijima, S; Migone, Aldo D

2013-07-30

112

Cosmogenic neon from precompaction irradiation of Kapoeta and Murchison  

NASA Technical Reports Server (NTRS)

Neon from hand-picked Murchison and Kapoeta grains, selected on the basis of the presence or absence of solar flare particle tracks, was analyzed in order to delineate the precompaction history of this material. The irradiated grains showed large enrichments of cosmogenic neon relative to the unirradiated grains. Galactic cosmic ray (GCR) exposure ages for the unirradiated grains yield the nominal values reported for the recent exposure history of these meteorites. Apparent minimum precompaction galactic exposure ages of 28 m.y. and 56 m.y. would have been obtained for Murchison and Kapoeta, respectively, if the cosmogenic effects in the irradiated grains were due to GCR irradiation. Since this seems unreasonably long, the cosmogenic neon in the irradiated grains may be due to spallation by solar cosmic rays. This, however, would require a more active early sun. The isotopic composition of the cosmogenic neon in these grains suggests a harder energy spectrum than is characteristic of present solar flares. Lack of apparent solar wind effects may require some kind of shielding, such as nebular gas.

Caffee, M. W.; Hohenberg, C. M.; Swindle, T. D.; Goswami, J. N.

1983-01-01

113

Functional theory of illusory conjunctions and neon colors  

Microsoft Academic Search

Illusory conjunctions are the incorrect perceptual combination of briefly presented colors and shapes. In the neon colors illusion, achromatic figures take on the color of an overlaid grid of colored lines. Both illusions are explained by a theory that assumes (a) poor location information or poor spatial resolution for some aspects of visual information and (b) that the spatial location

William Prinzmetal; Boaz Keysar

1989-01-01

114

A portable iodine stabilized helium-neon laser  

Microsoft Academic Search

A newly designed iodine stabilized helium-neon (He-Ne) laser is described which is stable to 3 x 10 to the -13th (1000-s sample time) but which exhibits an intensity dependent shift of about 8 kHz\\/W-sq cm. Closer agreement between dissimilar lasers is attained when the internal power densities are approximately equal.

Howard P. Layer

1980-01-01

115

Infrared absorption spectra of methylidene radicals in solid neon.  

PubMed

Infrared absorption lines of methylidene - (12)C(1)H, (13)C(1)H, and (12)C(2)H - dispersed in solid neon at 3 K, recorded after photolysis of methane precursors with vacuum-ultraviolet light at 121.6 nm, serve as signatures of these trapped radicals. PMID:24912563

Lu, Hsiao-Chi; Lo, Jen-Iu; Lin, Meng-Yeh; Peng, Yu-Chain; Chou, Sheng-Lung; Cheng, Bing-Ming; Ogilvie, J F

2014-06-26

116

Helium, neon, and argon in meteorites - A data compilation  

NASA Astrophysics Data System (ADS)

Tables are presented of data on helium, neon, and argon contents in 1158 individual meteorites, compiled from 393 different references. This compilation, which is an update of the Schultz and Kruse (1983) compilation, incorporates a total of 4127 analyses and missing classifications. The errors and misprints of the earlier compilation are eliminated.

Schultz, Ludolf; Kruse, Hartwig

1989-09-01

117

Molecular Iodine Fluorescence Using a Green Helium-Neon Laser  

ERIC Educational Resources Information Center

Excitation of molecular iodine vapor with a green (543.4 nm) helium-neon laser produces a fluorescence spectrum that is well suited for the upper-level undergraduate physical chemistry laboratory. Application of standard evaluation techniques to the spectrum yields ground electronic-state molecular parameters in good agreement with literature…

Williamson, J. Charles

2011-01-01

118

Comprehensive Testing of a Neon Cryogenic Capillary Pumped Loop.  

National Technical Information Service (NTIS)

This paper describes a comprehensive test program of a cryogenic capillary pumped loop (CCPL) using neon as the working fluid in the temperature range between 30 K and 40 K. The test article was originally designed to be used with nitrogen in the 70 K to ...

M. C. Kobel J. Ku

2001-01-01

119

Direct detection of dark matter with liquid argon and neon  

NASA Astrophysics Data System (ADS)

There is a great deal of observational evidence across a wide variety of scales that a large fraction of the universe and most of the matter in the universe is made up of some form of non-baryonic, dark matter. The most prominent candidate for dark matter is the weakly interacting massive particle or WIMP, with a mass between 1 GeV to a few TeV, and there are many current experiments aiming to detect these particles directly. The DEAP/CLEAN program seeks to detect dark matter and pp-solar neutrinos using liquid argon and liquid neon as targets. When ionizing radiation interacts in these liquids, scintillation light is produced. The timing or pulse shape of scintillation provides pulse shape discrimination (PSD) with which to identify the type of recoil that occurred in the liquid. As WIMP-nucleus scattering events would produce nuclear recoils but most of the backgrounds produce electronic recoils, PSD provides background rejection, allowing liquid argon- and neon-based detectors to achieve excellent sensitivity to dark matter. In this work, I describe the evidence for dark matter and review the state of current detection efforts. I then discuss observations of scintillation in liquid argon and liquid neon performed in prototype detectors at Yale and underground at SNOLAB in Ontario, Canada, focusing on measurements of PSD, the nuclear recoil scintillation efficiency and alpha backgrounds in these detectors. I describe the implications of these measurements for both the argon and neon components of the DEAP/CLEAN program, including simulations of a possible 10-tonne liquid neon detector. In the first appendix, I describe efforts at Yale to build a thermal column for the separation of isotopes, with applications to both dark matter and neutrinoless double-beta decay searches. In the second appendix, I describe operation of an evaporator system.

Lippincott, W. Hugh

2010-12-01

120

Cross-linking Chemistry of Squid Beak*  

PubMed Central

In stark contrast to most aggressive predators, Dosidicus gigas (jumbo squids) do not use minerals in their powerful mouthparts known as beaks. Their beaks instead consist of a highly sclerotized chitinous composite with incremental hydration from the tip to the base. We previously reported l-3,4-dihydroxyphenylalanine (dopa)-histidine (dopa-His) as an important covalent cross-link providing mechanical strengthening to the beak material. Here, we present a more complete characterization of the sclerotization chemistry and describe additional cross-links from D. gigas beak. All cross-links presented in this report share common building blocks, a family of di-, tri-, and tetra-histidine-catecholic adducts, that were separated by affinity chromatography and high performance liquid chromatography (HPLC) and identified by tandem mass spectroscopy and proton nuclear magnetic resonance (1H NMR). The data provide additional insights into the unusually high cross-link density found in mature beaks. Furthermore, we propose both a low molecular weight catechol, and peptidyl-dopa, to be sclerotization agents of squid beak. This appears to represent a new strategy for forming hard tissue in animals. The interplay between covalent cross-linking and dehydration on the graded properties of the beaks is discussed.

Miserez, Ali; Rubin, Daniel; Waite, J. Herbert

2010-01-01

121

Application of SQUID to magnetic contaminant detection  

NASA Astrophysics Data System (ADS)

We have developed a magnetic metallic contaminant detector using a high-temperature superconducting quantum interference device (HTS-SQUID) gradiometer for industrial products such as lithium ion batteries. Finding ultrasmall metallic contaminants is a critical issue for manufacturers producing commercial products such as lithium ion batteries. When contamination occurs, the manufacturer incurs a great loss in recalling the tainted products. We employed a permanent ring magnet for magnetizing the products in order to generate remnant fields only at the ends of the products, thereby reducing their impact in masking the field from a contaminant. For practical applications, the detection width of a sensor must be sufficiently large to identify an inclusion from above the product during inspection. Here, we made a large SQUID gradiometer 8 mm in width and compared its detection width with that of a conventional small sensor 3 mm wide. We found that the effective detection width of the 8 mm sensor was 11.6 mm. It was 1.8 times larger than that of the small sensor. Finally, a test of the system’s performance revealed that iron particles as small as 50 ?m × 50 ?m on the electrode of a lithium ion battery could be detected clearly.

Tanaka, S.; Akai, T.; Takemoto, M.; Hatsukade, Y.; Ohtani, T.; Ikeda, Y.; Suzuki, S.; Adachi, S.; Tanabe, K.

2010-11-01

122

Cross-linking chemistry of squid beak.  

PubMed

In stark contrast to most aggressive predators, Dosidicus gigas (jumbo squids) do not use minerals in their powerful mouthparts known as beaks. Their beaks instead consist of a highly sclerotized chitinous composite with incremental hydration from the tip to the base. We previously reported l-3,4-dihydroxyphenylalanine (dopa)-histidine (dopa-His) as an important covalent cross-link providing mechanical strengthening to the beak material. Here, we present a more complete characterization of the sclerotization chemistry and describe additional cross-links from D. gigas beak. All cross-links presented in this report share common building blocks, a family of di-, tri-, and tetra-histidine-catecholic adducts, that were separated by affinity chromatography and high performance liquid chromatography (HPLC) and identified by tandem mass spectroscopy and proton nuclear magnetic resonance ((1)H NMR). The data provide additional insights into the unusually high cross-link density found in mature beaks. Furthermore, we propose both a low molecular weight catechol, and peptidyl-dopa, to be sclerotization agents of squid beak. This appears to represent a new strategy for forming hard tissue in animals. The interplay between covalent cross-linking and dehydration on the graded properties of the beaks is discussed. PMID:20870720

Miserez, Ali; Rubin, Daniel; Waite, J Herbert

2010-12-01

123

The curvy photonics of squid camouflage  

NASA Astrophysics Data System (ADS)

Cephalopods (squids and octopuses) ubiquitously possess reflective structures in their skin composed of ``reflectin'' proteins. Although a few simple laminar, Bragg-stack type optical structures have been known in a handful of common squid species for some time, our extensive survey of optically active tissues of exotic deep-sea species has revealed complex, extended curvatures and topologies in dermal reflectors of these rarely-studied animals. Molecular deep-sequencing has revealed these structures also to be composed of reflectin-like proteins. Here we show a survey of some of these deep-sea reflector structures, and present evidence that each novel structure may be a transform of the radiance in the optical niche in the ocean where each of these species live, such that light reflecting off the sides of these animals in their specific ocean habitat resembles the light that would be transmitted through the animals if they were transparent, from many different viewing angles and possible ocean depths.

Sweeney, Alison; Holt, Amanda; Daniel, Morse; Stramski, Dariusz

2013-03-01

124

Sodium Extrusion by Internally Dialyzed Squid Axons  

PubMed Central

A method has been developed which allows a length of electrically excitable squid axon to be internally dialyzed against a continuously flowing solution of defined composition. Tests showed that diffusional exchange of small molecules in the axoplasm surrounding the dialysis tube occurred with a half-time of 2–5 min, and that protein does not cross the wall of the dialysis tube. The composition of the dialysis medium was (mM): K isethionate 151, K aspartate 151, taurine 275, MgCI2 4–10, NaCl 80, KCN 2, EDTA 0.1, ATP 5–10, and phosphoarginine 0–10. The following measurements were made: resting Na influx 57 pmole/cm2sec (n = 8); resting potassium efflux 59 pmole/ cm2sec (n = 4); stimulated Na efflux 3.1 pmole/cm2imp (n = 9); stimulated K efflux 2.9 pmole/cm2imp (n = 3); resting Na efflux 48 pmole/cm2sec (n = 18); Q10 Na efflux 2.2 (n = 5). Removal of ATP and phosphoarginine from the dialysis medium (n = 4) or external application of strophanthidin (n = 1) reversibly reduced Na efflux to 10–13 pmole/cm2sec. A general conclusion from the study is that dialyzed squid axons have relatively normal passive permeability properties and that a substantial fraction of the Na efflux is under metabolic control although the Na extrusion mechanism may not be working perfectly.

Brinley, F. J.; Mullins, L. J.

1967-01-01

125

35 ℏ two-stage SQUID system for gravity wave detection  

Microsoft Academic Search

We have designed, built and tested a two-stage SQUID measuring system which is primarily intended for use in a 50 mK omnidirectional gravity wave detection system. We fabricated three Nb-Al\\/AlOx-Nb trilayer SQUIDs on a single chip: there is one sensor SQUID and two readout SQUIDs which amplify the output of the sensor SQUID. At a temperature of 90 mK, we

I. Jin; A. Amar; T. R. Stevenson; F. C. Wellstood; A. Morse; W. W. Johnson

1997-01-01

126

High speed non-latching squid binary ripple counter  

SciTech Connect

High speed, single flux quantum (SFQ) binary scalers are important components in superconducting analog-to-digital converters (ADC). This paper reviews the concept for a SQUID ADC and the design of an SFQ binary ripple counter, and reports the simulation of key components, and fabrication and performance of non-latching SQUID scalers and SFQ binary ripple counters. The SQUIDs were fabricated with Nb/Nb/sub 2/O/sub 5//PbIn junctions and interconnected by monolithic superconducting transmission lines and isolation resistors. Each SQUID functioned as a bistable flip-flop with the input connected to the center of the device and the output across one junction. All junctions were critically damped to optimize the pulse response. Operation was verified by observing the dc I-V curves of successive SQUIDs driven by a cw pulse train generated on the same chip. Each SQUID exhibited constant-voltage current steps at 1/2 the voltage of the preceding device as expected from the Josephson voltage-to-frequency relation. Steps were observed only for the same voltage polarity of successive devices and for proper phase bias of the SQUID. Binary frequency division was recorded up to 40GHz for devices designed to operate to 28GHz.

Silver, A.H.; Phillips, R.R.; Sandell, R.D.

1985-03-01

127

Multistability and self-organization in disordered SQUID metamaterials  

NASA Astrophysics Data System (ADS)

Planar arrays of magnetoinductively coupled rf SQUIDs (Superconducting QUantum Interference Devices) belong to the emergent class of superconducting metamaterials that encompass the Josephson effect. These SQUID-based metamaterials acquire their electromagnetic properties from the resonant characteristics of their constitutive elements, i.e., the individual rf SQUIDs. In its simplest version, an rf SQUID consists of a superconducting ring interrupted by a Josephson junction. We investigate numerically the response of a two-dimensional rf SQUID metamaterial with respect to the driving frequency of an externally applied alternating magnetic field in the presence of disorder arising from critical current fluctuations of the Josephson elements; in effect, the resonance frequencies of individual SQUIDs are distributed randomly around a mean value. Bistability is observed in the current amplitude-frequency curves both in ordered and disordered SQUID metamaterials; moreover, bistability is favored by disorder through the improvement of synchronization between SQUID oscillators. Relatively weak disorder widens significantly the bistability region by helping the system to self-organize and leads to nearly homogeneous states that change smoothly with varying driving frequency. Also, the total current of the metamaterial is enhanced, compared with that of uncoupled SQUIDs, through the synergetic action of coupling and synchronization. The existence of simultaneously stable states that provide either high or low total current, allows the metamaterial to exhibit different magnetic responses that correspond to different values of the effective magnetic permeability. At low power of the incident field, high current amplitude states exhibit extreme diamagnetic properties corresponding to negative magnetic permeability in a narrow frequency interval.

Lazarides, N.; Tsironis, G. P.

2013-08-01

128

Fractionation of terrestrial neon by hydrodynamic hydrogen escape from ancient steam atmospheres  

NASA Technical Reports Server (NTRS)

Atmospheric neon is isotopically heavier than mantle neon. By contrast, nonradiogenic mantle Ar, Kr, and Xe are not known to differ from the atmosphere. These observations are most easily explained by selective neon loss to space; however, neon is much too massive to escape from the modern atmosphere. Steam atmospheres are a likely, if intermittent, feature of the accreting Earth. They occur because, on average, the energy liberated during accretion places Earth above the runaway greenhouse threshold, so that liquid water is not stable at the surface. It is found that steam atmospheres should have lasted some ten to fifty million years. Hydrogen escape would have been vigorous, but abundant heavy constituents would have been retained. There is no lack of plausible candidates; CO2, N2, or CO could all suffice. Neon can escape because it is less massive than any of the likely pollutants. Neon fractionation would have been a natural byproduct. Assuming that the initial Ne-20/Ne-22 ratio was solar, it was found that it would have taken some ten million years to effect the observed neon fractionation in a 30 bar steam atmosphere fouled with 10 bars of CO. Thicker atmospheres would have taken longer; less CO, shorter. This mechanism for fractionating neon has about the right level of efficiency. Because the lighter isotope escapes much more readily, total neon loss is pretty minimal; less than half of the initial neon endowment escapes.

Zahnle, K.

1991-01-01

129

A SQUID Bootstrap Circuit with a Large Parameter Tolerance  

NASA Astrophysics Data System (ADS)

The voltage biased (SQUID) bootstrap circuit (SBC) was recently introduced as an effective means to reduce the preamplifier noise contribution. We analyze the tolerances of the SBC noise suppression performance to spreads in SQUID and SBC circuit parameters. It is found that the tolerance to spread mainly caused by the integrated circuit fabrication process could be extended by a one-time adjustable current feedback. A helium-cooled niobium SQUID with a loop inductance of 350 pH is employed to experimentally verify the analysis. From this work, design criteria for fully integrated SBC devices with a high yield can be derived.

Zhang, Guo-Feng; Zhang, Yi; Hans-Joachim, Krause; Kong, Xiang-Yan; Andreas, Offenhäusser; Xie, Xiao-Ming

2013-01-01

130

HTS ion damage Josephson junction technology for SQUID arrays  

NASA Astrophysics Data System (ADS)

The high temperature superconducting (HTS) Josephson Junction (JJ) ion damage technology we are developing is well suited for making large SQUID arrays. We have studied arrays of similar SQUIDs together with large SQIFs (Superconducting Quantum Interference Filter) with 2000 SQUIDs of different loop areas. Magnetic field sensitivity has been measured in both types of devices as a function of bias current and temperature. The effects of the barrier thickness (from 20 to 80 nm) and JJ length (2 or 5 ?m) on characteristics have been investigated.

Ouanani, S.; Kermorvant, J.; Crété, D.-G.; Lemaître, Y.; Mage, J.-C.; Marcilhac, B.; Bergeal, N.; Malnou, M.; Lesueur, J.; Mailly, D.; Ulysse, C.

2014-05-01

131

Two junction effects in dc SQUID phase qubit  

NASA Astrophysics Data System (ADS)

The dc SQUID phase qubit was designed to allow one isolation junction to filter bias current noise from a second junction operating as a single junction phase qubit. As junctions shrink to minimize dielectric loss, the Josephson inductances of each junction approach the coupling loop inductance and this single junction picture appears inadequate. We consider a two-junction model of the dc SQUID phase qubit, where the qubit now corresponds to one of the normal oscillatory modes of the full SQUID. We discuss applications of this model to sweet spots in various control parameters and unusual behavior in the tunneling state measurement.

Cooper, B. K.; Kwon, H.; Przybysz, A. J.; Budoyo, R.; Anderson, J. R.; Lobb, C. J.; Wellstood, F. C.

2011-03-01

132

Autonomous Flying Controls Testbed.  

National Technical Information Service (NTIS)

The Flying Controls Testbed (FLiC) is a relatively small and inexpensive unmanned aerial vehicle developed specifically to test highly experimental flight control approaches. The most recent version of the FLiC is configured with 16 independent aileron se...

M. A. Motter

2005-01-01

133

Flying wires at Fermilab  

Microsoft Academic Search

Transverse beam profile measurement systems called flying wires have been installed and made operational in the Fermilab Main Ring and Tevatron accelerators. A flying wire is a device that passes (flies) a 25-?m carbon filament through a particle beam, transversely, at a constant velocity of between 2 and 5 m\\/s. Collisions between the beam particles and the wire produce secondary

J. Gannon; C. Crawford; D. Finley; R. Flora; T. Groves; M. MacPherson

1989-01-01

134

Glycine fluxes in squid giant axons.  

PubMed

1. The influx of a number of amino acids into squid giant axons has been studied. Particular emphasis has been placed on glycine and to a lesser extent glutamate. 2. To facilitate the study of the uptake of 14C-labelled amino acids a technique was devised in which the 14C taken up was measured directly in the intact axon with a glass scintillator fibre. This technique gave results similar to the usual technique in which the axoplasm was extruded for the assay of radioactivity. 3. The changes in glycine influx with extracellular glycine concentration suggests that two saturating components are present, one with high affinity and one with low affinity. 4. The glycine influx does not seem normally to be sensitive to the removal of extracellular sodium by replacement with choline. A Na-sensitive component appeared, however, after a period of immersion in artificial sea water. There was also some depression of glycine influx if Na were replaced by Li. 5. Glutamate uptake was greatly reduced by removal of extracellular Na in confirmation of work by Baker & Potashner (1973). Orthophosphate uptake was also greatly reduced by removal of extracellular Na. 6. CN reversibly inhibited glycine uptake after a delay, indicating that part of the uptake mechanism may require ATP. 7. 14C-labelled glycine injected into squid axons was found not to exchange to any serious extent with other compounds over periods of a few hours. The glycine efflux could therefore be studied. This was found to be markedly increased by extracellular glycine and by certain other neutral amino acids applied extracellularly in the artificial sea water. 8. The enhanced glycine efflux in extracellular glycine was not affected by ouabain and CN. 9. It is suggested that glycine uptake in squid axons involves two components. One is sensitive to CN and ouabain and probably derives energy from ATP break-down. The other is probably an ATP independent exchange diffusion system in which other amino acids as well as glycine can exchange for glycine. Both these systems are independent of extracellular Na concentration. A third Na-dependent system may appear under certain conditions. PMID:671272

Caldwell, P C; Lea, T J

1978-05-01

135

Glycine fluxes in squid giant axons.  

PubMed Central

1. The influx of a number of amino acids into squid giant axons has been studied. Particular emphasis has been placed on glycine and to a lesser extent glutamate. 2. To facilitate the study of the uptake of 14C-labelled amino acids a technique was devised in which the 14C taken up was measured directly in the intact axon with a glass scintillator fibre. This technique gave results similar to the usual technique in which the axoplasm was extruded for the assay of radioactivity. 3. The changes in glycine influx with extracellular glycine concentration suggests that two saturating components are present, one with high affinity and one with low affinity. 4. The glycine influx does not seem normally to be sensitive to the removal of extracellular sodium by replacement with choline. A Na-sensitive component appeared, however, after a period of immersion in artificial sea water. There was also some depression of glycine influx if Na were replaced by Li. 5. Glutamate uptake was greatly reduced by removal of extracellular Na in confirmation of work by Baker & Potashner (1973). Orthophosphate uptake was also greatly reduced by removal of extracellular Na. 6. CN reversibly inhibited glycine uptake after a delay, indicating that part of the uptake mechanism may require ATP. 7. 14C-labelled glycine injected into squid axons was found not to exchange to any serious extent with other compounds over periods of a few hours. The glycine efflux could therefore be studied. This was found to be markedly increased by extracellular glycine and by certain other neutral amino acids applied extracellularly in the artificial sea water. 8. The enhanced glycine efflux in extracellular glycine was not affected by ouabain and CN. 9. It is suggested that glycine uptake in squid axons involves two components. One is sensitive to CN and ouabain and probably derives energy from ATP break-down. The other is probably an ATP independent exchange diffusion system in which other amino acids as well as glycine can exchange for glycine. Both these systems are independent of extracellular Na concentration. A third Na-dependent system may appear under certain conditions.

Caldwell, P C; Lea, T J

1978-01-01

136

A Cyberinfrastructure for the National Ecological Observatory Network (NEON).  

NASA Astrophysics Data System (ADS)

The National Ecological Observatory Network (NEON) is an NSF-funded project designed to provide physical and information infrastructure to support the development of continental-scale, quantitative ecological sciences. The network consists of sixty sites located in the continental US, Alaska, Hawaii, and Puerto Rico, each site hosting terrestrial and aquatic sensors and observational apparati that acquire data across multiple ecoclimatic domains. As well, an airborne remote sensing platform provides spectral and LiDAR data, and acquisition of data sets from external agencies allows for land-use studies. Together, this data is ingested, vetted, processed, and curated by a standards-based, provenance-driven, metadata-rich cyberinfrastructure, which will provide not only access to but discovery and manipulation of NEON data, and the construction of integrative data products and inputs for ecological forecasting that address fundamental processual questions in climate change, land use change, and invasive species.

Schimel, D.; Berukoff, S. J.

2011-12-01

137

Discovery of solar wind neon in the Allende meteorite  

NASA Technical Reports Server (NTRS)

Insert gases have been measured in seven sieve fractions of a disaggregated sample of the Allende meteorite. The disaggregation was done by ultrasonic treatment in water and by freeze-thawing. This sample consititutes the first gas-rich portion known to occur in the Allende meteorite. The composition of the trapped neon is solar, i.e., Neon-B, and the gas-rich samples contain more trapped Ne-20 than Ar-36. The set of sieve fractions show an anticorrelation of Ne-20 content and grain size. Gas-richness seems to be quite common among the CV3 meteorites with Allende added to the earlier known cases of Mokoia, Vigarano, and Efremovka.

Heymann, D.; Palma, R. L.

1986-01-01

138

Heteronuclear collisions between laser-cooled metastable neon atoms  

NASA Astrophysics Data System (ADS)

We investigate heteronuclear collisions in isotope mixtures of laser-cooled metastable (3P2) neon. Experiments are performed with spin-polarized atoms in a magnetic trap for all two-isotope combinations of the stable neon isotopes 20Ne, 21Ne, and 22Ne. We determine the rate coefficients for heteronuclear ionizing collisions to ?21,20=(3.9±2.7)×10-11 cm3/s, ?22,20=(2.6±0.7)×10-11 cm3/s, and ?21,22=(3.9±1.9)×10-11 cm3/s. We also study heteronuclear elastic collision processes and give upper bounds for heteronuclear thermal relaxation cross sections. This work significantly extends the limited available experimental data on heteronuclear ionizing collisions for laser-cooled atoms involving one or more rare gas atoms in a metastable state.

Schütz, Jan; Feldker, Thomas; John, Holger; Birkl, Gerhard

2012-08-01

139

Cation Interdiffusion in Squid Giant Axons  

PubMed Central

Radiotracer techniques were used to study the influxes and effluxes of various univalent cations in internally perfused squid giant axons. Membrane currents and conductances were determined by the voltage-clamp technique under analogous internal and external conditions. Both sodium-containing and sodium-free internal and external media were studied. Membrane impedance was measured with an ac impedance bridge to determine the general magnitude and time course of the impedance loss which accompanied the excitation process in both varieties of external media. Maximum transmembrane currents were found to be of comparable magnitude to the charge transfer associated with the peak interdiffusion flux measured under the same conditions. The product of the membrane resistance and the interdiffusion flux remained constant over a wide range of resistance and flux values, both at rest and during activity, both in sodium-containing and sodium-free media. The implications of these findings for excitation theory are discussed.

Tasaki, Ichiji; Singer, Irwin; Watanabe, Akira

1967-01-01

140

Reducing decoherence in dc SQUID phase qubits  

NASA Astrophysics Data System (ADS)

This thesis examines sources of dissipation and dephasing in a dc SQUID phase qubit. Coupling of the qubit to the bias lines and lossy dielectrics causes the qubit to lose quantum information through a process known generally as decoherence. Using knowledge of the possible sources of decoherence, a dc SQUID phase qubit is designed with parameters that should have made it resistant to dissipation and dephasing from those sources. Device PB9 was a dc SQUID with one small area 0.23 (mum)2 Josephson junction with a critical current of 130 nA, which was meant to be the qubit junction, and a larger area 5 (mum)2 junction with a critical current of 8.6 muA, which acted as part of an inductive isolation network. The qubit junction was shunted by a 1.5 pF low-loss interdigitated capacitor. The dc current bias line had an on-chip LC filter with a cutoff frequency of 180 MHz. The other control lines were also designed to minimize coupling of dissipative elements to the qubit. According to a theoretical model of the dissipation and dephasing, the qubit was expected to have an energy relaxation T1 ? 8.4 mus and dephasing time To ˜ 1 mus. Because of the relatively high Josephson inductance of the qubit junction, the device did not act perform like a conventional isolated single-junction phase qubit. Instead, the resonant modes that I observed were the normal modes of the entire SQUID. At 20 mK and a frequency of 4.047 GHz, the maximum energy relaxation time of the device was found to be 350 +/- 70 ns, despite the optimized design. Through a study of T1 versus applied flux, T1 was found to depend on the strength of the coupling of the microwave drive line to the qubit. When the line was more coupled, T1 was shorter. This was evidence that the microwave line was overcoupled to the qubit, and was limiting the lifetime of the excited state T1. Through a study of the spectroscopic coherence time T2* , which measured the effects of low-frequency inhomogeneous broadening and higher frequency dephasing from noise, I discovered that device PB9 has several sweet spots. In particular, the presence of a sweet spot with respect to critical current fluctuations allowed me to identify critical current noise as a major source of broadening and dephasing in the qubit. From the spectroscopy I estimated the 1/f critical current noise power density at 1 Hz was SI01 (1Hz) ? 10 (nA) 2/Hz and the 1/f flux noise power spectral density at 1 Hz was Sphi (1Hz) ? (110 muphi 0)2/Hz. Both of these values were quite high, possibly due to switching of the device between measurements.

Przybysz, Anthony J.

141

Development and Characteristic Evaluation of High Resolution SQUID Magnetometer  

NASA Astrophysics Data System (ADS)

High resolution SQUID magnetometers had previously been developed which was designed for nerves, muscles, slices of brain tissue and small animals. In these SQUID system, diameters of the pickup coil were a few mm and the distances between the pickup coil and the outside surface of the dewer was a few mm. In this study, we developed a super high resolution SQUID magnetometer having higher spatial resolution than previous systems. In this system, diameter of the pickup coil is 200 µm, the distance between the pickup coil and the outside surface of the dewar is 800 µm. The typical system noise in the magnetic shielded room is 2.7pT/?Hz in the frequency from 1Hz to 10kHz. We discuss features of the measurement system and the spatial resolution of this SQUID system using a current source model. It can be discriminated extreme of magnetic field pattern obtained from the meander line of 500 µm interval.

Kobayashi, Koichiro; Hashimoto, Hidehito; Kawakatsu, Masaki; Uchikawa, Yoshinori

142

Weld quality evaluation using a high temperature SQUID array  

SciTech Connect

This paper presents preliminary data for evaluating weld quality using high temperature SQUIDS. The SQUIDS are integrated into an instrument known as the SQUID Array Microscope, or SAMi. The array consists of ll SQUIDs evenly distributed over an 8.25 mm baseline. Welds are detected using SAMi by using an on board coil to induce eddy currents in a conducting sample and measuring the resulting magnetic fields. The concept is that the induced magnetic fields will differ in parts of varying weld quality. The data presented here was collected from three stainless steel parts using SAMi. Each part was either solid, included a good weld, or included a bad weld. The induced magnetic field's magnitude and phase relative to the induction signal were measured. For each sample considered, both the magnitude and phase data were measurably different than the other two samples. These results indicate that it is possible to use SAMi to evaluate weld quality.

Clark, D. D. (David D.); Espy, M. A. (Michelle A.); Kraus, Robert H., Jr.; Matlachov, A. N. (Andrei N.); Lamb, J. S. (Jessica S.)

2002-01-01

143

Electrophoretic and Immunological Studies of Squid Axoplasm Proteins.  

National Technical Information Service (NTIS)

By disc electrophoresis of the axoplasm of Dosidicus gigas, 14 protein bands have been resolved. Antibodies to the intra-axonal proteins and to squid blood proteins were produced in rabbits. By Ouchterlony's technique, six antigenic components can be demo...

F. Huneeus-Cox

1964-01-01

144

Squid as nutrient vectors linking Southwest Atlantic marine ecosystems  

NASA Astrophysics Data System (ADS)

Long-term investigations of three abundant nektonic squid species from the Southwest Atlantic, Illex argentinus, Doryteuthis gahi and Onykia ingens, permitted to estimate important population parameters including individual growth rates, duration of ontogenetic phases and mortalities. Using production model, the productivity of squid populations at different phases of their life cycle was assessed and the amount of biomass they convey between marine ecosystems as a result of their ontogenetic migrations was quantified. It was found that squid are major nutrient vectors and play a key role as transient 'biological pumps' linking spatially distinct marine ecosystems. I. argentinus has the largest impact in all three ecosystems it encounters due to its high abundance and productivity. The variable nature of squid populations increases the vulnerability of these biological conveyers to overfishing and environmental change. Failure of these critical biological pathways may induce irreversible long-term consequences for biodiversity, resource abundance and spatial availability in the world ocean.

Arkhipkin, Alexander I.

2013-10-01

145

MicroSQUID Force Microscopy in a Dilution Refrigerator  

NASA Astrophysics Data System (ADS)

We present a new generation of a scanning microSQUID microscope operating in an inverted dilution refrigerator. The microSQUIDs have a size of 1.21m and a magnetic flux sensitivity of 120 and thus a field sensitivity of 550. The scan range at low temperatures is about 80 m and a coarse displacement of 5 mm in x and y direction has been implemented. The microSQUID-to-sample distance is regulated using a tuning fork based force detection. A microSQUID-to-sample distance of 420 nm has been obtained. The reliable knowledge of this distance is necessary to obtain a trustworthy estimate of the absolute value of the superconducting penetration depth. An outlook will be given on the ongoing direction of development.

Hykel, D. J.; Wang, Z. S.; Castellazzi, P.; Crozes, T.; Shaw, G.; Schuster, K.; Hasselbach, K.

2014-06-01

146

Magnetoencephalography using a Multilayer hightc DC SQUID Magnetometer  

NASA Astrophysics Data System (ADS)

We describe tests of the use of a multilayer highTc DC SQUID magnetometer for magnetoencephalography (MEG) and compare our measurements with results obtained using a lowTc SQUID sensor. The integration of bias reversal readout electronics for highTc DC SQUID magnetometry into a commercial MEG data acquisition system is demonstrated. Results of measurements performed on a salinefilled head phantom are shown and the detection of an auditory evoked magnetic response of the human cortex elicited by a stimulus is illustrated. Future modifications of highTc DC SQUID sensors for applications in MEG, in order to reach a resolution of 1 fT/?Hz at 77.5 K over a wide frequency band, are outlined.

Faley, M. I.; Poppe, U.; Borkowski, R. E. Dunin; Schiek, M.; Boers, F.; Chocholacs, H.; Dammers, J.; Eich, E.; Shah, N. J.; Ermakov, A. B.; Slobodchikov, V. Yu.; Maslennikov, Yu. V.; Koshelets, V. P.

147

MicroSQUID Force Microscopy in a Dilution Refrigerator  

NASA Astrophysics Data System (ADS)

We present a new generation of a scanning microSQUID microscope operating in an inverted dilution refrigerator. The microSQUIDs have a size of 1.21 \\upmu m2 and a magnetic flux sensitivity of 120 \\upmu ? 0 / ?{Hz} and thus a field sensitivity of 550 \\upmu G/ ?{Hz} . The scan range at low temperatures is about 80 \\upmu m and a coarse displacement of 5 mm in x and y direction has been implemented. The microSQUID-to-sample distance is regulated using a tuning fork based force detection. A microSQUID-to-sample distance of 420 nm has been obtained. The reliable knowledge of this distance is necessary to obtain a trustworthy estimate of the absolute value of the superconducting penetration depth. An outlook will be given on the ongoing direction of development.

Hykel, D. J.; Wang, Z. S.; Castellazzi, P.; Crozes, T.; Shaw, G.; Schuster, K.; Hasselbach, K.

2014-04-01

148

HTS SQUIDs for the nondestructive evaluation of composite structures  

NASA Astrophysics Data System (ADS)

While LTS and HTS SQUIDs have successfully been applied in the detection of flaws in aircraft grade aluminium structures for well over a decade, interest has recently spread to a type of new material, namely composites. One example, carbon fibre reinforced polymer (CFRP), is increasingly being favoured by the aircraft industry because of its strength to weight ratio and the fact that it is corrosion-resistant. Material and defect characterization using SQUIDs is still at an early stage, but due to expected rapid expansion in the use of such materials, there is ample scope for the application of HTS SQUIDs. Here we have applied HTS SQUID single-layer gradiometers to investigate artificially created defects in CFRP samples.

Carr, Chris; Graham, David; Macfarlane, John C.; Donaldson, Gordon B.

2003-12-01

149

High-T(c) SQUIDs: Noise and Applications.  

National Technical Information Service (NTIS)

A major challenge in the design and operation of high transition temperature (Tc) Superconducting Quantum Interference Devices (SQUIDs) is their potential to exhibit substantially higher levels of noise at low frequency f when exposed to earths magnetic f...

H. M. Cho

2001-01-01

150

Electron-impact excitation cross sections of neon  

Microsoft Academic Search

To determine the direct electron-impact excitation cross sections with the optical method, one must measure all transitions out of a level, as well as the cascade into the level of interest from higher-lying energy levels. Considered here are the ten levels of the 2p53p configuration of neon, whose emissions to lower levels fall within a range of 540-810 nm. This

J. Ethan Chilton; M. D. Stewart; Chun C. Lin

2000-01-01

151

Multilayer Adsorption of Neon, Hydrogens, and Carbon Monoxide on Graphite  

Microsoft Academic Search

Multilayer adsorption of neon, hydrogens (H _2, HD, and D_2), and carbon monoxide on graphite have been investigated using ellipsometric-coverage vapor-pressure isotherm measurements. Chemical potentials at layer condensations and widths of the layer condensation steps were tabulated, and layer critical points were determined from the temperature dependence of the widths for all five adsorbates. In Ne we do not find

Hong Wu

1995-01-01

152

Deep mantle origin of kimberlite magmas revealed by neon isotopes  

Microsoft Academic Search

We measured noble gases in olivines extracted from alteration-free samples of the Udachnaya-East kimberlite pipe, eastern Siberia. Neon isotope ratios indicate that the kimberlite has a less nucleogenic Ne signature than a typical mid-ocean ridge basalt (MORB) source, which is consistent with the less radiogenic 40Ar\\/36Ar ratio compared to MORB and subcontinental lithospheric mantle (SCLM) sources. Based on He-Ne systematics,

Hirochika Sumino; Ichiro Kaneoka; Kyosuke Matsufuji; Alexander V. Sobolev

2006-01-01

153

Helium–neon systematics and the structure of the mantle  

Microsoft Academic Search

We present here a comparison of helium and neon isotopes in the mantle. These two elements provide important constraints on the structure of the mantle and the exchange between the upper and the lower mantle. Using two low 4He\\/3He on-ridge hotspots located in the south Atlantic we observe that radiogenic He correlates with nucleogenic Ne. Using data from Loihi seamount

Manuel Moreira; Claude Jean Allègre

1998-01-01

154

Equation of state for solid neon from quantum theory  

Microsoft Academic Search

The equation of state P(V,T) for solid neon is obtained from a quantum theoretical treatment using two- and three-body forces, and an anharmonic treatment for lattice vibrations and temperature effects within the Einstein approximation. Our results are in excellent agreement with experiment for the pressure and temperature range of up to 200 GPa and 900 K. The calculated equation of

P. Schwerdtfeger; Andreas Hermann

2009-01-01

155

Charge radii of neon isotopes across the sd neutron shell  

SciTech Connect

We report on the changes in mean square charge radii of unstable neon nuclei relative to the stable {sup 20}Ne, based on the measurement of optical isotope shifts. The studies were carried out using collinear laser spectroscopy on a fast beam of neutral neon atoms. High sensitivity on short-lived isotopes was achieved thanks to nonoptical detection based on optical pumping and state-selective collisional ionization, which was complemented by an accurate determination of the beam kinetic energy. The new results provide information on the structural changes in the sequence of neon isotopes all across the neutron sd shell, ranging from the proton drip line nucleus and halo candidate {sup 17}Ne up to the neutron-rich {sup 28}Ne in the vicinity of the ''island of inversion.'' Within this range the charge radius is smallest for {sup 24}Ne with N=14 corresponding to the closure of the neutron d{sub 5/2} shell, while it increases toward both neutron shell closures, N=8 and N=20. The general trend of the charge radii correlates well with the deformation effects which are known to be large for several neon isotopes. In the neutron-deficient isotopes, structural changes arise from the onset of proton-halo formation for {sup 17}Ne, shell closure in {sup 18}Ne, and clustering effects in {sup 20,21}Ne. On the neutron-rich side the transition to the island of inversion plays an important role, with the radii in the upper part of the sd shell confirming the weakening of the N=20 magic number. The results add new information to the radii systematics of light nuclei where data are scarce because of the small contribution of nuclear-size effects to the isotope shifts which are dominated by the finite-mass effect.

Marinova, K. [Institut fuer Physik, Universitaet Mainz, D-55099 Mainz (Germany); Laboratory of Nuclear Reactions, Joint Institute of Nuclear Research, 141980 Dubna (Russian Federation); Geithner, W.; Kappertz, S.; Kloos, S.; Kotrotsios, G.; Neugart, R.; Wilbert, S. [Institut fuer Physik, Universitaet Mainz, D-55099 Mainz (Germany); Kowalska, M.; Keim, M. [Physics Department, CERN, CH-1211 Geneva 23 (Switzerland); Blaum, K. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Lievens, P. [Laboratorium voor Vaste-Stoffysica en Magnetisme, K.U.Leuven, B-3001 Leuven (Belgium); Simon, H. [Institut fuer Kernphysik, TU Darmstadt, D-64289 Darmstadt (Germany)

2011-09-15

156

FMR study of neon implanted LPE grown garnet layers  

Microsoft Academic Search

The results of a study on the effects of neon implantation into bubble films are presented. Epitaxial films of composition La, Ga:YIG and Tm, Ca, Ge:YIG were implanted with 300 keV, 1014 Ne+ ions\\/cm2. The films were studied by ferromagnetic resonance (FMR) and by double crystal X-ray diffraction. The FMR spectra of the ion-implanted films exhibit an additional set of

H. A. Algra; W. de Roode; R. A. Henskens; J. M. Robertson

1981-01-01

157

Double Auger Decay following K-Shell Photoionization of Neon  

Microsoft Academic Search

Using a COLTRIMS setup at LBNL-ASL, our group photoionized Neon just above the K-ionization threshold. The measurement allows us to investigate a simultaneous angular and energy correlation between the three continuum electrons of the subsequent double Auger decay pathway: Ne(1s-1)^+ + e^-photo -> Ne^3+ + e^-photo + e^-Auger + e^-Auger, where we measure two of the electrons directly and infer

M. P. Jones; M. Schoffler; T. Jahnke; K. Kreidi; J. Titze; R. Dorner; C. Stuck; Th. Weber; A. Belkacem; A. Landers

2010-01-01

158

Frequency-domain SQUID multiplexing of transition-edge sensors  

Microsoft Academic Search

We describe our frequency-domain readout multiplexer for transition-edge sensor (TES) bolometers and present measurements of an eight-channel multiplexer. Each sensor is biased with a sinusoidal bias at a distinct frequency. As the sensor absorbs power, it amplitude-modulates its sinusoidal bias. Sensor currents are summed and measured with a single superconducting quantum interference device (SQUID) array. The SQUID array consists of

T. M. Lanting; Hsiao-Mei Cho; J. Clarke; M. A. Dobbs; W. L. Holzapfel; A. T. Lee; M. Lueker; P. L. Richards; A. D. Smith; H. G. Spieler

2005-01-01

159

SQUID sensor application for small metallic particle detection  

Microsoft Academic Search

High-Tc superconducting quantum interference device (SQUID) is an ultra-sensitive magnetic sensor. Since the performance of the SQUID is improved and stabilized, now it is ready for application. One strong candidate for application is a detection system of magnetic foreign matters in industrial products or beverages. There is a possibility that ultra-small metallic foreign matter has been accidentally mixed with industrial

Saburo Tanaka; Yoshimi Hatsukade; Takeyoshi Ohtani; Shuichi Suzuki

2009-01-01

160

High Tc SQUID Detector for Magnetic Metallic Particles in Products  

Microsoft Academic Search

High-Tc superconducting quantum interference device (SQUID) is an ultra-sensitive magnetic sensor. After the discovery of the high-Tc superconducting materials, the performance of the high-Tc SQUID has been improved and stabilized. One strong candidate for application is a detection system of magnetic foreign matters in industrial products. There is a possibility that ultra-small metallic foreign matter has been accidentally mixed with

Saburo Tanaka; Tomonori Akai; Yoshimi Hatsukade; Shuichi Suzuki

2009-01-01

161

An Efficient Superconducting Transformer Design for SQUID Magnetometry  

NASA Astrophysics Data System (ADS)

We describe a novel superconducting transformer design for the efficient transfer of magnetic flux from a macroscopic pickup coil to a low-inductance SQUID. A large number of highly-efficient one-to-one transformer elements are wired in series and in parallel, for the primary and secondary of the transformer, respectively. This transformer coupling allows us to isolate the SQUID from the microwave resonances inherent in high-inductance coils.

Mates, J. A. B.; Irwin, K. D.; Vale, L. R.; Hilton, G. C.; Cho, H. M.

2014-08-01

162

Highly Sensitive and Easy-to-Use SQUID Sensors  

Microsoft Academic Search

We have developed a novel family of low-noise superconducting quantum interference devices (SQUIDs) to cover a wide range of applications. These sensors are robust and easy to use without compromising noise performance. They are optimized for operation with our high-speed direct-coupled flux-locked loop (FLL) electronics XXF-1. For the readout of cryogenic detectors, series arrays of 16 SQUIDs with 3 nH

D.. Drung; C.. Assmann; J.. Beyer; A.. Kirste; M.. Peters; F.. Ruede; T.. Schurig

2007-01-01

163

ELECTROPHORETIC AND IMMUNOLOGICAL STUDIES OF SQUID AXOPLASM PROTEINS.  

PubMed

By disc electrophoresis of the axoplasm of Dosidicus gigas, 14 protein bands have been resolved. Anti-bodies to the intra-axonal proteins and to squid blood proteins were produced in rabbits. By Ouchterlony's technique, six antigenic components can be demonstrated in axoplasm; the combined use of disc electrophoresis and immune diflusion in agar resolves seven antigenic components in axoplasm; none of these components is detectable in squid blood. PMID:14107426

HUNEEUS-COX, F

1964-03-01

164

SQUID magnetometry applied as non-invasive electroanalytic chemical technique  

SciTech Connect

This paper reports on a SQUID magnetometer, employed as a highly sensitive ammeter, used to perform standard electroanalytic chemical measurements non- invasively. Specifically, the magnetic fields generated by the net ionic movement in the solution of a driven electrochemical system is detected by the gradiometer coils. The SQUID signal can then be compared to conventional current measurements. One such standard measurement investigated is Cyclic Voltametry (CV) which determines the I-V characteristics of an electrochemical system yielding critical kinetic parameters.

Jette, B.D.; MacVicar, M.L.A. (Specialty Materials Lab., Massachusetts Inst. of Technology, Cambridge, MA (US))

1991-03-01

165

PROTEIN SOLUBILITY AND PRODUCTION OF GELS FROM JUMBO SQUID  

Microsoft Academic Search

Solubility at several ionic strengths (0 to 1.0 M), pH (2 to 13) and gelling capacity of jumbo squid Dosidicus gigas muscle proteins were evaluated. Protein recovery was >90% at pH 9-12. Autohydrolysis was evaluated and affected only sarcoplasmic proteins. Folding score was 5 on all gels. Strength was higher for thermal gels prepared from squid fin (50.2 1.2 N)

GABRIELA DE LA FUENTE-BETANCOURT; FERNANDO GARCÍA-CARREÑO; M. A. NAVARRETE DEL TORO; JULIO H. CÓRDOVA-MURUETA; MARÍA ELENA LUGO-SÁNCHEZ

2009-01-01

166

An Economical Magnetocardiogram System Based on High-Tc SQUIDs  

Microsoft Academic Search

An economical magnetocardiogram (MCG) system is built in our laboratory. It mainly consists of a MCG data acquisition stage equipped with two high-Tc superconducting quantum interference device (SQUID) magnetometers, a data processing stage with digital filtering and a one-layer mu-metal magnetically shielded room in conjunction with a high-Tc SQUID based active compensation. Experimental results show that a noise level of

Zhuo Li; Xue-Min Zhu; Li-Hua Zhang; Xu-Guang Huang; Yu-Feng Ren; Geng-Hua Chen; Qian-Sheng Yang; Ji Feng

2006-01-01

167

Nova LMC 1990 no. 1: The first extragalactic neon nova  

NASA Technical Reports Server (NTRS)

International Ultraviolet Explorer (IUE) observations of nova LMC (Large Magellanic Cloud) 1990 No. 1, the first neon (or ONeMg) nova observed outside the Galaxy are presented. The observations were obtained from 17 Jan. to Mar. 1990, with especially dense coverage during the first 25 days of the outburst. (The neon nova categorization is based on the detection of forbidden Ne 3-4 lines in optical spectra; the ultraviolet neon lines were not detected.) During the first 30 days of the outburst, the radiative losses were dominated by the N 5 delta 1240 and C 4 delta 1550 lines. The maximum ejection velocity was approximately 8000 km/s, based on the blue absorption edge of the C 4 P-Cygni profile. Early in the outburst of Nova LMC 1990 No. 1 the UV luminosity alone was approximately 3 times 10 to the 38th power erg/sec, implying that the bolometric luminosity was well in excess of the Eddington luminosity for a one solar mass object.

Sonneborn, George; Shore, Steven N.; Starrfield, Sumner G.

1990-01-01

168

Presence of mature eggs in olive fruit fly, Bactrocera oleae (Diptera Tephritidae), at different constant photoperiods and at two temperatures  

Microsoft Academic Search

The effect of the constant photoperiod on presence of mature eggs in olive fruit fly was investigated. Adults of B. oleae were submitted to different photoperiodic treatments (LL:DD), at temperature of 20 °C: 9:15, 10:14, 12:12, 15:9, 16:8, continuous light (LL) and continuous dark (DD). Light was obtained from neon tubes and the light intensity, estimated inside the plexiglas cage,

Alfio RASPI; Angelo CANALE; Augusto LONI

169

Isotopically anomalous neon in meteoritic nanodiamonds: Formation during type II supernova explosions  

NASA Astrophysics Data System (ADS)

We hypothesize the formation of neon associated with isotopically anomalous xenon (Xe-HL) in meteoritic nanodiamonds and designated as Ne-X through the mixing of the Ne-HL and Ne-S subcomponents. The Ne-HL subcomponent is neon from the helium (He/C) zone of a type II supernova or a mixture of neon from this zone and its hydrogen zone, while the Ne-S subcomponent is spallation neon formed during a supernova explosion in nuclear spallation reactions induced by high-energy protons. Based on this hypothesis and the presumed abundances of neon isotopes in the zones of a high-mass (25 M ?) supernova after its explosion, we have calculated the abundances of neon components in nanodiamond separates and its grain-size fractions. Our calculations have shown the following. (1) The main source of Ne-HL is neon from the helium zone of the supernova; as a result, the 20Ne/22Ne and 21Ne/22Ne ratios for Ne-X are 0.26 ± 0.03 and 0.19 ± 0.04, respectively. The isotopic composition of Ne-X is identical to that for Ne-A2 if Ne-HL is produced by the mixing of neon from the helium and hydrogen zones in proportion 1: 1.06. (2) In meteoritic nanodiamonds, the main neon abundance is determined by neon of the P3 component (Ne-P3). Ne-P3 is retained during thermal metamorphism, because it is sited in traps of the crystal lattice of diamond with a high energy of its activation. (3) The Ne-X/Ne-P3 ratio increases with nanodiamond grain size; as a result, there is no need to invoke an additional neon component (Ne-P6) to interpret the data on neon in meteoritic nanodiamonds.

Fisenko, A. V.; Semenova, L. F.

2008-09-01

170

[Biochemistry and functional characterization of squid mantle meat (Dosidicus gigas)].  

PubMed

A study for the characterization of frozen giant squid mantle (meat) protein stored at -25 degrees C for 8 month was started. In the present research, the following functional properties were investigate: emulsifying, water holding and gel forming capacities. Optimal conditions for the separation and differentiation of miofibrillar and sarcoplasmatic proteins were also studied. It was found that the unfrozen giant squid mantle meat es capable of emulifying 2.817,4 g of oil/g of protein and holding capacity was 3.64 g of water/g of protein. Related to the gel forming capacity, it was not obtain, probably due to excessive storage of the meat. With regard to miofibrilar protein obtention of the squid mantle meat, it was found that two low ionic strength washings (I = 0.05), the sarcoplasmic proteins were practically eliminated from the protein matrix. The differentiation of miofibrilar and sarcoplasmatic proteins was obtained by PAGE-SDS of the squid mantle meat extracted at two different ionic strength (I = 0.05 and I = 0.5). This work demonstrates that the giant squid mantle protein has a high emulsifying and water holding capacity, and it can be used, as a raw material, for the improvement of sausage products. About the gelling products, more studies will be necessary with fresh squid mantle meat to conclude about this functional property. PMID:11464670

Abugoch, L; Guarda, A; María Pérez, L; Isabel Donghi, M

2000-12-01

171

On the mechanism of populating 3p levels of neon under pumping by a hard ioniser  

SciTech Connect

The effect of quenching additives on the luminescence properties of helium - neon mixtures under pumping by {alpha} particles emitted from {sup 210}Po atoms is considered. It is concluded that, under excitation by a heavy charged particle, the population of the 3p'[1/2]{sub 0} level of neon is not related to the dissociative recombination of molecular ions. It is suggested that the most likely channels for populating the 3p level are the excitation transfer from metastable helium atoms to neon atoms and direct excitation of neon by nuclear particles and secondary electrons. (lasers and active media)

Khasenov, M U [Fotonika LLC, ul. Utegen batyra 112, 050062 Almaty (Kazakhstan)

2011-03-31

172

A Slice of Apple Fly  

NSDL National Science Digital Library

In this activity, learners build an instrument for catching and observing flies. Learners act as entomologists, attract flies into a jar using a slice of apple, and then observe the flies' behavior. Learners distinguish between male and female flies and study fly reproduction. The learning time for this activity can vary significantly, depending on how long learners want to observe the flies. Learners release the flies outside at the end of the activity.

Bill Nye And Nye Labs, Llc

2001-01-01

173

Fly ash carbon passivation  

DOEpatents

A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

La Count, Robert B; Baltrus, John P; Kern, Douglas G

2013-05-14

174

Nuclear magnetic resonance experiments with dc SQUID amplifiers  

SciTech Connect

The development and fabrication of dc SQUIDs (Superconducting QUantum Interference Devices) with Nb/Al{sub 2}O{sub 3}/Nb Josephson junctions is described. A theory of the dc SQUID as a radio-frequency amplifier is presented, with an optimization strategy that accounts for the loading and noise contributions of the postamplifier and maximizes the signal-to-noise ratio of the total system. The high sensitivity of the dc SQUID is extended to high field NMR. A dc SQUID is used as a tuned radio-frequency amplifier to detect pulsed nuclear magnetic resonance at 32 MHz from a metal film in a 3.5 Tesla static field. A total system noise temperature of 11 K has been achieved, at a bath temperature of 4.2 K. The minimum number of nuclear Bohr magnetons observable from a free precession signal after a single pulse is about 2 {times} 10{sup 17} in a bandwidth of 25 kHz. In a separate experiment, a dc SQUID is used as a rf amplifier in a NQR experiment to observe a new resonance response mechanism. The net electric polarization of a NaClO{sub 3} crystal due to the precessing electric quadrupole moments of the Cl nuclei is detected at 30 MHz. The sensitivity of NMR and NQR spectrometers using dc SQUID amplifiers is compared to the sensitivity of spectrometers using conventional rf amplifiers. A SQUID-based spectrometer has a voltage sensitivity which is comparable to the best achieved by a FET-based spectrometer, at these temperatures and operating frequencies.

Heaney, M.B. (California Univ., Berkeley, CA (USA). Dept. of Physics Lawrence Berkeley Lab., CA (USA))

1990-11-01

175

Sodium Movements in Perfused Squid Giant Axons  

PubMed Central

Sodium movements in internally perfused giant axons from the squid Dosidicus gigas were studied with varying internal sodium concentrations and with fluoride as the internal anion. It was found that as the internal concentration of sodium was increased from 2 to 200 mM the resting sodium efflux increased from 0.09 to 34.0 pmoles/cm2sec and the average resting sodium influx increased from 42.9 to 64.5 pmoles/cm2sec but this last change was not statistically significant. When perfusing with a mixture of 500 mM K glutamate and 100 mM Na glutamate the resting efflux was 10 ± 3 pmoles/cm2sec and 41 ± 10 pmoles/cm2sec for sodium influx. Increasing the internal sodium concentration also increased both the extra influx and the extra efflux of sodium due to impulse propagation. At any given internal sodium concentration the net extra influx was about 5 pmoles/cm2impulse. This finding supports the notion that the inward current generated in a propagated action potential can be completely accounted for by movements of sodium.

Rojas, Eduardo; Canessa-Fischer, Mitzy

1968-01-01

176

SQUIDs Fabrication with the Weak Links  

NASA Astrophysics Data System (ADS)

We present a new technique to fabricate SQUIDs nanobridges as the weak links. We have shown that these chemical-mechanical polishing based process has minimal impact on Al and Nb superconducting properties as demonstrated on long microstructures. This process allows realizing ``2D nanobridges'' formed of the same material as the electrodes and with same thickness. The Nb nanobridges are approximately 100 nm wide and long and 20 nm thick. Similar structures have been fabricated in Ti and Al. We are working at increasing the quality of the deposited films especially in the initial phase for this is the material that remains after CMP and forms these very thin nanobridges. In these very thin structures, it is critical to have high quality material being deposited from the very start of the deposition process as it is those initial layers that are left as a device after CMP [1]. Also allows producing ``3D structures'' with nanobridges thinner (e.g. 20 nm) than the leads (e.g. 100 nm) in a single lithography step. In this case, we also show that the nanobridge can be made of a material other than the leads thus allow SS'S or SNS type of weak links.[4pt] [1] A. Ramzi et al., Physics Procedia, Volume 36, (2012), 211--216.

Ramzi, Abdelaziz; Charlebois, Serge A.

2013-03-01

177

Using NEON to Measure Adaptation of Vegetation to Changes in Environmental Forcing  

NASA Astrophysics Data System (ADS)

The National Ecological Observatory Network (NEON) is a national-scale research platform for documenting and analyzing the impacts of climate change, land-use change, and invasive species on ecology. NEON features sensor networks and experiments linked by cyberinfrastructure to record and archive ecological data for at least 30 years. NEON partitions the United States into 20 ecoclimatic domains. Each domain hosts one fully instrumented core site in a wildland area and two re-locatable sites, which aims to capture ecologically significant gradients (e.g. landuse). Using standardized protocols and an open data policy, NEON data will be gathered from the level of the gene and organism to populations and communities, with extrapolations to the continental scale. In conjunction with environmental data, NEON will conduct field observations and analyses of biological specimens to track biodiversity, population dynamics, productivity, phenology, infectious disease, biogeochemistry and ecohydrology. Here we present a few examples of the type of research NEON will enable using this data. The NEON network will measure and scale many environmental factors that affect vegetation, e.g. temperature, precipitation, and nutrient availability. Direct monitoring of vegetation will enable the study of acclimatory and adaptive changes in vegetation properties over different time scales. Such data will improve the representation of vegetation responses to environmental change in models. The vision behind NEON aims to advance our ability to quantitatively predict ecological change.

Martin, P. H.; Kao, R.; Gibson, C.

2009-12-01

178

Interactions of 10.5 Gev/C Pions with Neon Nuclei.  

National Technical Information Service (NTIS)

The interactions of 10.5-GeV/c pions with neon nuclei were studied and compared with pi p interactions. The average number of charged pions from neon interactions is 3.45 +- .03; of nucleons, 4.45 +- .13. The charged pion multiplicity distribution for neo...

W. M. Yeager

1976-01-01

179

The solubility of neon, nitrogen and argon in distilled water and seawater  

Microsoft Academic Search

Large discrepancies in published neon and nitrogen solubility data limit the interpretation of oceanic measurements of these gases. We present new solubility measurements for neon, nitrogen and argon in distilled water and seawater, over a temperature range of 1–30?C. Water was equilibrated with air at measured temperatures, salinities and pressures. Dissolved Ne concentrations were then determined by isotope dilution using

Roberta C. Hamme; Steven R. Emerson

2004-01-01

180

Development of a Neon Cryogenic TurboExpander with Magnetic Bearings  

Microsoft Academic Search

A cryogenic turbo-expander with active magnetic bearings was made and tested in a reverse-Brayton cycle refrigerator using neon as working fluid. Turbine isentropic efficiency is a very important factor for the refrigerator since it affects the performance of the refrigerator significantly. Properties of neon are suitable for the working fluid in a refrigerator to cool HTS (High Temperature Superconducting) applications.

H. Hirai; M. Hirokawa; S. Yoshida; Y. Kamioka; A. Takaike; H. Hayashi; H. Okamoto; Y. Shiohara

2010-01-01

181

Prospects for Imaging Magnetic Nanoparticles Using a Scanning Squid Microscope  

NASA Astrophysics Data System (ADS)

Magnetic nanoparticles have a number of present and proposed uses: in the fields of nanobiotechnology for magnetic separation, magnetic manipulation, magnetic sensing, and in situ heating; for high density storage in both conventional and patterned media; and for spintronic devices. Although there are well established techniques for measuring the magnetic properties of large numbers of particles, it is desirable to magnetically image individual nanoparticles and clusters with small numbers of nanoparticles to determine such properties as their coercive fields, magnetic moments, and anisotropy energies. Wernsdorfer and co-workers [1] have shown that the magnetic reversal fields of small magnetic particles can be determined using a nanoSQUID. However, in these experiments nanoparticles were deposited directly on the SQUID. Such a technique would be difficult to use for the determination of, for example, the distribution in particle properties of a collection of particles. Woods and coworkers [2] determined the anisotropy energy of a film of magnetic particles from SQUID microscope measurements of the magnetic noise. In these experiments a large number of particles were included in the region sensed by the SQUID pickup loop, so that only average properties were determined. Measurement of the magnetic properties of individual nanoparticles is a challenge using any scanning probe microscopy, but is possible with the scanning SQUID microscope. In this talk I will describe different modes for imaging magnetic nanoparticles, present simple calculations of the size of signal expected for these modes as a function of such parameters as the size and saturation magnetization of the particles, the size of the pickup loop, and the spacing between the SQUID pickup loop and the nanoparticle, and compare these signals with the noise currently and ultimately available in scanning SQUID sensors [3]. I conclude that such measurements should be possible with the very small pickup loop (0.6 ?m diameter) nanoSQUIDs that have now been demonstrated [4]. We have built and operated a high spatial resolution, variable sample temperature scanning SQUID microscope for imaging magnetic nanoparticles. I will describe this microscope and present results on imaging magnetic nanoparticles. * Work done in collaboration with Beena Kalisky, Lisa Qian, and Kathryn Moler. [4pt] [1] W. Wernsdorfer et al. Phys. Rev. Lett. 78, 1791 (1997). [0pt] [2] S.I. Woods, J.R. Kirtley, S. Sun, and R.H. Koch, Phys. Rev. Lett. 87, 137205 (2001). [0pt] [3] J.R. Kirtley, Supercond. Sci. Technol. 22, 064008 (2009). [0pt] [4] N.C. Koshnick, M.E. Huber, J.A. Bert, C.W. Hicks, J. Large, H. Edwards, and K.A. Moler, Appl. Phys. Lett. 93, 243101 (2007).

Kirtley, John

2010-03-01

182

Microwave SQUID multiplexers for low-temperature detectors  

NASA Astrophysics Data System (ADS)

We report on the development of a SQUID multiplexer operated at microwave frequencies. This multiplexer can accommodate any detector that can be read out with SQUIDs, including transition-edge sensors, magnetic calorimeters, and superconductor-insulator-superconductor tunnel junction detectors. The total bandwidth, which is set by the HEMT amplifier, can be as high as 5 GHz, allowing the readout of 103-104 low-bandwidth detectors into one coaxial cable. Alternatively, in a low-Q circuit each SQUID can have a bandwidth as high as 100-200 MHz, allowing multiplexing of high-bandwidth sensors, such as optical TES photon detectors and antenna-coupled hot-electron TES bolometers. Each SQUID must be flux biased at a sensitive point on its response curve. We describe a multiplexed flux biasing scheme that makes it possible to flux bias a large array of SQUIDs with only one additional coaxial cable. We further present a hybrid "TDMA" multiplexer optimized for the high dynamic range and slew rate of fast X-ray calorimeters.

Irwin, K. D.; Beall, J. A.; Doriese, W. B.; Duncan, W. D.; Hilton, G. C.; Mates, J. A. B.; Reintsema, C. D.; Schmidt, D. R.; Ullom, J. N.; Vale, L. R.; Zink, B. L.; Lehnert, K. W.

2006-04-01

183

Coupled non-uniform bi-squid: A numerical investigation  

NASA Astrophysics Data System (ADS)

This work investigates through numerical simulations a novel device that improvesdynamic range and linearity. The standard DC SQUID can increase in linearity by adding athird junction, changing to a device known as the bi-SQUID. It is known that the dynamicrange can increase by connecting SQUIDs in series, and it has been shown that nonuniformityin the loops sizes in arrays of SQUIDs can produce a unique 'anti'-peak at thezero magnetic flux (device know as a SQIF). Thus, combining these ideas we can improvethe dynamic range and design a highly linear device with a unique 'anti'-peak. Hence, this device can be referred to as a bi-SQIF or non-uniform bi-SQUID array. Results have shown that the maximum voltage swing increase proportional to N, where N is the number of loops connected in series. The spur free dynamic range also improves as N increases, which is directly related to the linearity of the device. Therefore, we have designed a device which can lead to improvements which can be applicable to low noise amplifier (LNA), and provide a platform for creating "electrically" small antennas.

Longhini, Patrick; Berggren, Susan; Palacios, Antonio; In, Visarath; Leese de Escobar, Anna

2012-06-01

184

Collagen from diamondback squid (Thysanoteuthis rhombus) outer skin.  

PubMed

Collagens (acid-solubilized and pepsin-solubilized collagens) were prepared from diamondback squid outer skin and partially characterized. The yields of acid-solubilized and pepsin-solubilized collagens were about 1.3 and 35.6%, respectively, on a dry weight basis. Pepsin-solubilized collagen was heterotrimer with a chain composition of ala2a3. The patterns of peptide fragments were different from that of porcine skin collagen. Denaturation temperature was 27.5 degrees C, about 10 degrees C lower than that of porcine collagen. The amino acid composition of pepsin-solubilized collagen from diamondback squid outer skin was similar to that from cuttlefish outer skin. This squid is big among squid species, and its skin is thick. It is clear that diamondback squid outer skin has a potential as an alternative source of collagen to bovine skin and bone. At present, collagen using aquatic materials such as skin (cod and a deep-sea fish) and scale (sea bream and anchovy) is the development stage in the related industries. Unless the problem of BSE infection in land animals is resolved aquatic materials as an alternative source of collagen will attract much attention in the cosmetic and medical fields. PMID:15241939

Nagai, Takeshi

2004-01-01

185

Calibration of SQUID vector magnetometers in full tensor gradiometry systems  

NASA Astrophysics Data System (ADS)

Measurement of magnetic vector or tensor quantities, namely of field or field gradient, delivers more details of the underlying geological setting in geomagnetic prospection than a scalar measurement of a single component or of the scalar total magnetic intensity. Currently, highest measurement resolutions are achievable with superconducting quantum interference device (SQUID)-based systems. Due to technological limitations, it is necessary to suppress the parasitic magnetic field response from the SQUID gradiometer signals, which are a superposition of one tensor component and all three orthogonal magnetic field components. This in turn requires an accurate estimation of the local magnetic field. Such a measurement can itself be achieved via three additional orthogonal SQUID reference magnetometers. It is the calibration of such a SQUID reference vector magnetometer system that is the subject of this paper. A number of vector magnetometer calibration methods are described in the literature. We present two methods that we have implemented and compared, for their suitability of rapid data processing and integration into a full tensor magnetic gradiometry, SQUID-based, system. We conclude that the calibration routines must necessarily model fabrication misalignments, field offset and scale factors, and include comparison with a reference magnetic field. In order to enable fast processing on site, the software must be able to function as a stand-alone toolbox.

Schiffler, M.; Queitsch, M.; Stolz, R.; Chwala, A.; Krech, W.; Meyer, H.-G.; Kukowski, N.

2014-08-01

186

Environmental effects on recreational squid jigging fishery catches  

NASA Astrophysics Data System (ADS)

Experimental fishing sessions simulating the operating procedures of the recreational fishery for the European squid that operates at inshore Palma Bay (Balearic Islands, Spain) were conducted to investigate the effects of environmental variables on squid catches. The catch per unit of effort (cpue) of recreational-like jigging sessions showed a seasonal pattern (higher cpue during colder months). Two alternative hypotheses can explain such a pattern. First, squid could migrate inshore during colder months to seek spatio-temporal windows within which the sea temperature maximize spawning success. Second, the timing of the seasonal reproductive peak and the growth rate of any given cohort would result in a higher percentage of squid whose body size is greater than the gear-specific vulnerability threshold during the colder months. The combination of environmental variables that maximized cpue was a low sea surface temperature, a low windspeed, low atmospheric pressure, and days close to the new moon. A specific period of the day, narrowly around sunset, favoured the catches. Within this narrow period, the sunlight is still sufficient to allow the recreational fishing lures to be effective, and the squid have already shifted to a more active pattern of movement characteristic of the night-time period.

Cabanellas-Reboredo, Miguel; Alós, Josep; Palmer, Miquel; Morales-Nin, Beatriz

2012-08-01

187

Mobile HTS SQUID System for Nondestructive Evaluation of Aircraft Structures  

NASA Astrophysics Data System (ADS)

For the detection of deep-lying flaws in aircraft structures, a mobile eddy-current system is being developed in conjunction with a high-temperature superconductor (Yba_2Cu_3O_7) thin-film HTS SQUID gradiometer. The challenge is to operate the SQUID sensor during movement in strong ambient fields, independent of orientation. A planar rf double hole gradiometer with a gradient sensitivity of 500 fT/(cm ?Hz) was designed for that purpose. Two different cooling concepts were successfully implemented: the SQUID operation in the vacuum region of a lightweight nitrogen cryostat, constructed for operation in any orientation, and the use of a commercial Joule-Thomson cryocooler for liquid-nitrogen-free SQUID cooling. With a SQUID integration scheme using a sapphire cold finger, motion-related additional noise is nearly eliminated. Using a system equipped with a differential eddy current excitation, two-dimensional scans were performed to find fatigue cracks and corrosion pits hidden below several layers of aluminum. For demonstration in the Lufthansa maintenance facility at Frankfurt Airport, the system was used to detect flaws in aircraft wheels. Work in progress includes developing longer base gradiometers for detection of deep flaws.

Krause, Hans-Joachim; Hohmann, Rainer; Grueneklee, Michael; Zhang, Yi; Braginski, Alex I.

1997-03-01

188

Low pressure broadening and shift of the 2 p 53 p-2 p 56 s neon spectral lines  

Microsoft Academic Search

The broadening and shift of four spectral lines arising from the 2 p 53 p-2 p 56 s transitions of neon emitted from a low pressure glow discharge in pure neon and a neon-helium mixture have been measured. The values of the pressure broadening and shift coefficients are determined. The results are interpreted in terms of the impact theory assuming

A. Bielski; K. Bryl; W. Dokurno; E. Lisicki

1981-01-01

189

Fluorescence of protonated pyrene and coronene in neon matrices  

NASA Astrophysics Data System (ADS)

Fluorescence spectra of protonated pyrene and coronene in solid neon have been observed. Laser excitation of the Sn ? S0 transitions of the cations results in an extended, vibrationally-resolved S1 ? S0 fluorescence with onset at 487.8 and 695.4 nm for protonated pyrene and coronene, respectively. Vibrational assignment of the spectra has been made on the basis of the calculated frequencies of normal modes in the ground electronic state. The astrophysical relevance of the frequencies inferred for these protonated cations is discussed.

Garkusha, Iryna; Fulara, Jan; Maier, John P.

2012-10-01

190

The study of photoionization of neon-like Ar IX  

NASA Astrophysics Data System (ADS)

The photoionization of the ground state of neon-like is investigated and the autoionizing spectrum of 2 s22 p52P 1/2ns, nd and 2 s2 p62S 1/2np Rydberg series of Ar IX are studied by using the Breit-Pauli Hamiltonian within the R-matrix theory combine with the QB method of Quigly-Berrington [L. Quigley, K.A. Berrington, J. Pelan, Comput. Phys. Commun. 144 (1998) 225]. We predict the energies and widths of four Rydberg series of Ar IX.

Liang, Liang; Chao, Zhou; Xie, Zun-Xian

2009-02-01

191

The abundances of neon, sulfur, and argon in planetary nebulae  

NASA Technical Reports Server (NTRS)

New infrared observations of Ne II, Ar III, and S IV are used in optical observations of other ionization states of the considered elements to evaluate the abundances of neon, argon, and sulfur in 18 planetary nebulae. Attention is also given to one or more of the infrared lines in 18 other nebulae. It is pointed out that S IV was detected in approximately 90% of the observed objects, while Ar III was found in about 80%, and Ne II in roughly one-third. It is noted that optical observations typically include only a limited region of the nebula, while the infrared measurements frequently involve integration over the entire nebular image.

Beck, S. C.; Lacy, J. H.; Townes, C. H.; Aller, L. H.; Geballe, T. R.; Baas, F.

1981-01-01

192

Expected intensities of solar neon-like ions  

NASA Technical Reports Server (NTRS)

A study of the expected intensities of the stronger solar neon-like ion emission lines, some not yet observed, is carried out to compare with the observational situation. The potential usefulness of the 2p5 3s(3P2) - 2p6 forbidden line as a density diagnostic is discussed, and new electric quadrupole lines in the soft X-ray range are noted. 'Observability diagrams' are presented as a convenient overview of the known and unobserved lines. The S VII resonance lines appear to have anomalous intensities.

Bhatia, A. K.; Kastner, S. O.

1985-01-01

193

In situ measurements of neon in the thermosphere  

NASA Technical Reports Server (NTRS)

The open source neutral mass spectrometer on the Atmosphere Explorer-C satellite has measured neon in the thermosphere. The absolute density of Ne is close to that predicted by using the ground level fraction by volume of Ne along with the assumption of diffusive equilibrium above 100 km. Data is presented for both geomagnetically quiet and disturbed circular orbits. At 290 km, a typical low latitude value of Ne is 3.0 x 10 to the 4th/cu cm. At this altitude Ne appears to be predominantly controlled by temperature except during magnetic disturbances, when offsetting forces due to wind systems may be present.

Potter, W. E.; Kayser, D. C.

1976-01-01

194

Optimizing Sampling Efficiency for Biomass Estimation Across NEON Domains  

NASA Astrophysics Data System (ADS)

Over the course of 30 years, the National Ecological Observatory Network (NEON) will measure plant biomass and productivity across the U.S. to enable an understanding of terrestrial carbon cycle responses to ecosystem change drivers. Over the next several years, prior to operational sampling at a site, NEON will complete construction and characterization phases during which a limited amount of sampling will be done at each site to inform sampling designs, and guide standardization of data collection across all sites. Sampling biomass in 60+ sites distributed among 20 different eco-climatic domains poses major logistical and budgetary challenges. Traditional biomass sampling methods such as clip harvesting and direct measurements of Leaf Area Index (LAI) involve collecting and processing plant samples, and are time and labor intensive. Possible alternatives include using indirect sampling methods for estimating LAI such as digital hemispherical photography (DHP) or using a LI-COR 2200 Plant Canopy Analyzer. These LAI estimations can then be used as a proxy for biomass. The biomass estimates calculated can then inform the clip harvest sampling design during NEON operations, optimizing both sample size and number so that standardized uncertainty limits can be achieved with a minimum amount of sampling effort. In 2011, LAI and clip harvest data were collected from co-located sampling points at the Central Plains Experimental Range located in northern Colorado, a short grass steppe ecosystem that is the NEON Domain 10 core site. LAI was measured with a LI-COR 2200 Plant Canopy Analyzer. The layout of the sampling design included four, 300 meter transects, with clip harvests plots spaced every 50m, and LAI sub-transects spaced every 10m. LAI was measured at four points along 6m sub-transects running perpendicular to the 300m transect. Clip harvest plots were co-located 4m from corresponding LAI transects, and had dimensions of 0.1m by 2m. We conducted regression analyses with LAI and clip harvest data to determine whether LAI can be used as a suitable proxy for aboveground standing biomass. We also compared optimal sample sizes derived from LAI data, and clip-harvest data from two different size clip harvest areas (0.1m by 1m vs. 0.1m by 2m). Sample sizes were calculated in order to estimate the mean to within a standardized level of uncertainty that will be used to guide sampling effort across all vegetation types (i.e. estimated within × 10% with 95% confidence). Finally, we employed a Semivariogram approach to determine optimal sample size and spacing.

Abercrombie, H. H.; Meier, C. L.; Spencer, J. J.

2013-12-01

195

Melting curves for neon calculated from pure theory  

NASA Astrophysics Data System (ADS)

The melting curve of neon is determined from nonequilibrium molecular dynamics simulations performed at constant pressure, using ab initio pair potentials. The effects of various approximations on the predicted melting points are investigated through the use of pair potentials calculated at different levels of accuracy, and the inclusion of quantum effects on the motion via a Wigner-Kirkwood quantum effective potential. To avoid superheating of the model crystal, nucleation sites for melting are provided by creating clusters of void defects in the crystal prior to heating. The calculated melting curves are shown to be in good agreement with experimental measurements. Comparisons are made with similar calculations previously carried out for argon.

Solca, Jan; Dyson, Anthony J.; Steinebrunner, Gerold; Kirchner, Barbara; Huber, Hanspeter

1998-03-01

196

Adsorption of nitrogen, argon, and neon on sintered copper and of neon on argon-coated sintered copper at low temperatures  

Microsoft Academic Search

The results of measurements of adsorption isotherms are given for nitrogen, argon, and neon on bare sintered copper and on sintered copper covered with a monolayer of argon. The temperatures employed where 77.3 K for the N2 and argon, and 17.26, 20.22, 22.64, 25.71, and 27.00 K for the neon, and the pressure range was from 0.25 to 200 Torr.

E. Lerner; J. G. Daunt

1972-01-01

197

NMR of room temperature samples with a flux-locked dc SQUID  

Microsoft Academic Search

Superconducting quantum interference devices (SQUIDs) are the most sensitive detectors of magnetic fields. Since SQUIDs detect the magnetic flux rather than its rate of change, they can be used to great advantage to measure nuclear magnetic resonance (NMR) signals at low fields and frequencies. We have used a dc (direct-current) SQUID operated in flux-locked mode to significantly improve upon our

S. Kumar; W. F. Avrin; B. R. Whitecotton

1996-01-01

198

RANGE EXPANSION AND TROPHIC INTERACTIONS OF THE JUMBO SQUID, DOSIDICUS GIGAS, IN THE CALIFORNIA CURRENT  

Microsoft Academic Search

Although jumbo squid (Dosidicus gigas) have been oc- casional visitors to the California Current over the last century, their abundance and distribution increased be- tween 2002 and 2006. We report several time series of jumbo squid relative abundance from commercial and recreational fisheries as well as resource surveys and food habits studies. To evaluate the trophic relationships of jumbo squid,

JOHN C. FIELD; KEN BALTZ; A. JASON PHILLIPS

199

Simulating the indirect handline jigging effects on the European squid Loligo vulgaris in captivity  

Microsoft Academic Search

The European squid Loligo vulgaris is an important target species of commercial and recreational fisheries in the NW Mediterranean. Handline jigging is one of the most common fishing gears used by both of these fisheries to catch squid, which are trapped when they try to seize the lure with their tentacles. An unknown but possibly significant number of squid are

Miguel Cabanellas-Reboredo; Josep Alós; Miquel Palmer; Roman Grädel; Beatriz Morales-Nin

2011-01-01

200

The fine magnetic image of a high TC SQUID probe microscope  

Microsoft Academic Search

We have developed a high TC SQUID probe microscope. A high permeability probe was used as a flux guide to improve its spatial resolution. The SQUID head with the flux guide makes it possible to measure samples with high spatial resolution in air at room temperature. The end of the flux guide and the SQUID were in vacuum with a

Tadayuki Hayashi; Hideo Itozaki

2005-01-01

201

1\\/f noise in radio frequency SQUIDs made of niobium thin films  

Microsoft Academic Search

Applications of Superconducting Quantum Interference Devices (SQUIDs) usually require high sensitivity at relatively low frequencies, often down to 1 Hz or lower. Excess noise, typically with a spectral density scaling inversely as the frequency, can substantially reduce the sensitivity of SQUIDs at low frequencies. We have studied 1\\/f noise in niobium rf-SQUIDs in some detail. To reduce any noise contribution

Michael Mueck; John Clarke; Christoph Heiden

1994-01-01

202

Activation of fly ash  

DOEpatents

Fly ash is activated by heating a screened magnetic fraction of the ash in a steam atmosphere and then reducing, oxidizing and again reducing the hydrothermally treated fraction. The activated fly ash can be used as a carbon monoxide disproportionating catalyst useful in the production of hydrogen and methane.

Corbin, D.R.; Velenyi, L.J.; Pepera, M.A.; Dolhyj, S.R.

1986-08-19

203

Ever Fly a Tetrahedron?  

ERIC Educational Resources Information Center

Few things capture the spirit of spring like flying a kite. Watching a kite dance and sail across a cloud spotted sky is not only a visually appealing experience it also provides a foundation for studies in science and mathematics. Put simply, a kite is an airfoil surface that flies when the forces of lift and thrust are greater than the forces of…

King, Kenneth

2004-01-01

204

A Flying Summer Camp  

ERIC Educational Resources Information Center

Describes a five-day summer camp which provided 12 children, ages 9-14, with a complete flying experience. The training consisted of ground school and one hour actual flying time, including the basics of aircraft control and a flight prepared and executed by the students. (MLH)

Mercurio, Frank X.

1975-01-01

205

A Better Fly Trap  

NSDL National Science Digital Library

In this activity, learners observe fly behavior and then build a flytrap. They make more observations, compare the effectiveness of different traps, and modify their traps to increase their effectiveness. In doing so, learners consider what variables make for an effective trap as well as learning how to study the behavior of an animal. Even pesky flies provide an interesting challenge.

Science, Lawrence H.

1979-01-01

206

Mutant Fruit Flies  

NSDL National Science Digital Library

A general audience discussion of common fruit fly mutations. The site includes simplified illustrations, and a discussion of fruit fly chromosomes. Presented by Exploratorium at the museum of science art and human perception at the Palace of Fine Arts San Francisco.

0002-11-30

207

Activation of fly ash  

DOEpatents

Fly ash is activated by heating a screened magnetic fraction of the ash in a steam atmosphere and then reducing, oxidizing and again reducing the hydrothermally treated fraction. The activated fly ash can be used as a carbon monoxide disproportionating catalyst useful in the production of hydrogen and methane.

Corbin, David R. (New Castle, DE); Velenyi, Louis J. (Lyndhurst, OH); Pepera, Marc A. (Northfield, OH); Dolhyj, Serge R. (Parma, OH)

1986-01-01

208

NMR/MRI with hyperpolarized gas and high Tc SQUID  

DOEpatents

A method and apparatus for the detection of nuclear magnetic resonance (NMR) signals and production of magnetic resonance imaging (MRI) from samples combines the use of hyperpolarized inert gases to enhance the NMR signals from target nuclei in a sample and a high critical temperature (Tc) superconducting quantum interference device (SQUID) to detect the NMR signals. The system operates in static magnetic fields of 3 mT or less (down to 0.1 mT), and at temperatures from liquid nitrogen (77K) to room temperature. Sample size is limited only by the size of the magnetic field coils and not by the detector. The detector is a high Tc SQUID magnetometer designed so that the SQUID detector can be very close to the sample, which can be at room temperature.

Schlenga, Klaus (Eggenstein, DE); de Souza, Ricardo E. (Recife, BR); Wong-Foy, Annjoe (Berkeley, CA); Clarke, John (Berkeley, CA); Pines, Alexander (Berkeley, CA)

2000-01-01

209

Microwave SQUID Multiplexer for the Readout of Metallic Magnetic Calorimeters  

NASA Astrophysics Data System (ADS)

We have realized a frequency-domain multiplexing technique for the readout of large metallic magnetic calorimeter detector arrays. It is based on non-hysteretic single-junction SQUIDs and allows for a simultaneous readout of hundreds or thousands of detectors by using a single cryogenic high electron mobility transistor amplifier and two coaxial cables that are routed from room-temperature to the detector array. We discuss the working principle of the multiplexer and present details about our prototype multiplexer design. We show that fabricated devices are fully operational and that characteristic SQUID parameters such as the input sensitivity of the SQUID or the resonance frequency of the readout circuit can be predicted with confidence. Our best device so far has shown a magnetic flux white noise level of 1.4 m which can in future be reduced by an optimization of the fabrication processes as well as an improved microwave readout system.

Kempf, S.; Gastaldo, L.; Fleischmann, A.; Enss, C.

2014-06-01

210

Application of SQUIDs for registration of biomagnetic signals  

NASA Astrophysics Data System (ADS)

Supersensitive magnetometric systems based on low-temperature SQUIDs have been designed to conduct research in cardiology (magnetocardiography) and to examine distribution of magnetic nanoparticles in biologic objects. Such SQUID magnetometric systems are distinguished by their noise immunity enabling research in nonscreened rooms. High repeatability of research outcomes has been confirmed. The use of magnetocardiographic systems has permitted a new screening information technology to be developed to diagnose heart diseases at early stages. Magnetic imaging of heart's action currents is an ideal way to test local electrical heterogeneity of myocardium. It is shown that magnetocardiography has a significant potential for both basic science of analysis of heart's biosignals and clinical cardiologic practice. A SQUID magnetometric system measuring magnetic signals radiated by the organs of laboratory animals is described. Information technology for automatic recording and transforming magnetometric data has been developed; the measurement of signals over rats' livers while injecting intravenously the nanoparticles of iron oxides and lead solutions are presented.

Voitovych, I. D.; Primin, M. A.; Sosnytskyy, V. N.

2012-04-01

211

FlyNome  

NSDL National Science Digital Library

FlyNome is the brainchild of _Drosophila_ researcher, Christopher Yohn, of the Skirball Institute in New York City. Yohn created this Web site out of the frustration involved in trying to find the stories behind the names of fruit fly genes. New to the Scout Report, FlyNome "is intended to be a resource for the _Drosophila_ community by serving as a reliable tool to which fly researchers can refer and contribute." Users may search the database by gene symbol, full gene name, name of contributor, or simply browse all entries. FlyNome will also track down stories (by request) for genes not currently in the database. The site also includes useful Web links and a FAQ page.

212

Ionized calcium concentrations in squid axons  

PubMed Central

Values for ionized [Ca] in squid axons were obtained by measuring the light emission from a 0.1-mul drop of aequorin confined to a plastic dialysis tube of 140-mum diameter located axially. Ionized Ca had a mean value of 20 x 10(-9) M as judged by the subsequent introduction of CaEGTA/EGTA buffer (ratio ca. 0.1) into the axoplasm, and light measurement on a second aequorin drop. Ionized Ca in axoplasma was also measured by introducing arsenazo dye into an axon by injection and measuring the Ca complex of such a dye by multichannel spectrophotometry. Values so obtained were ca. 50 x 10(-9) M as calibrated against CaEGTA/EGTA buffer mixtures. Wth a freshly isolated axon in 10 mM Ca seawater, the aequorin glow invariably increased with time; a seawater [Ca] of 2-3 mM allowed a steady state with respect to [Ca]. Replacement of Na+ in seawater with choline led to a large increase in light emission from aequorin. Li seawater partially reversed this change and the reintroduction of Na+ brought light levels back to their initial value. Stimulation at 60/s for 2-5 min produced an increase in aequorin glow about 0.1% of that represented by the known Ca influx, suggesting operationally the presence of substantial Ca buffering. Treatment of an axon with CN produced a very large increase in aequorin glow and in Ca arsenazo formation only if the external seawater contained Ca.

1976-01-01

213

Primitive neon isotopes in Terceira Island (Azores archipelago) [rapid communication  

NASA Astrophysics Data System (ADS)

We present the first neon data, as well as new helium data, on Terceira Island (Azores archipelago, Portugal). Clear 20Ne and 21Ne excesses compared to air are observed ( 20Ne/ 22Ne > 11.2) and moreover, the samples show a more primitive 21Ne/ 22Ne ratio than MORB, confirming that the Azores hotspot can be considered as sampling a "primitive", relatively undegassed, reservoir. Most 4He/ 3He isotopic ratios range between 80,000 and 63,500 (˜ 9 to 11.5 R/Ra), being similar to those previously reported by [1] [M. Moreira, R. Doucelance, B. Dupré, M. Kurz, C.J. Allègre, Helium and lead isotope geochemistry in the Azores archipelago, Earth Planet. Sci. Lett. 169 (1999) 189-205] . A more primitive 4He/ 3He ratio of ˜ 50,000 (R/Ra ˜ 15) was obtained in one sample, but we cannot completely exclude the possibility of a cosmogenic 3He contribution for this sample. Our study illustrates that the neon systematics can be more capable than helium to constrain the ultimate origin of hotspots in geodynamic settings dominated by plume-ridge interaction.

Madureira, Pedro; Moreira, Manuel; Mata, João; Allègre, Claude Jean

2005-05-01

214

Helium-neon laser treatment transforms fibroblasts into myofibroblasts  

SciTech Connect

The differentiation of myofibroblastic cells from normal human gingival fibroblasts in vitro has been established by transmission electron microscopy and quantitated by immunohistochemistry, using antigelsolin monoclonal antibodies. Untreated control cultures were compared to cultures exposed to Helium-Neon (He-Ne) laser irradiation. A direct and massive transformation of the cultured fibroblasts into myofibroblasts was observed as early as 24 hours after laser treatment, whereas control cultures were comprised of only resting fibroblasts and active fibroblasts. This in vitro induction of myofibroblasts may be analogous to that which occurs in vivo. Therefore we undertook a similar study using biopsies from gingival tissues after wisdom tooth extraction. Myofibroblasts were present in the connective tissue of laser-treated gums 48 hours after irradiation, but not in untreated contralateral control tissues. These data provide evidence that the primary biologic effect of the Helium-Neon laser on connective tissue is the rapid generation of myofibroblasts from fibroblasts. The induction of a phenotype with contractile properties may have clinical significance in the acceleration of the wound-healing process.

Pourreau-Schneider, N.; Ahmed, A.; Soudry, M.; Jacquemier, J.; Kopp, F.; Franquin, J.C.; Martin, P.M. (CNRS Unite 1175, Marseille (France))

1990-07-01

215

Electronic energies for Neon dimer dication radiative charge transfer  

NASA Astrophysics Data System (ADS)

This research was conducted to find the shape of the potential energy surfaces for the Neon dimer dication, designated Ne2(+2), to include all symmetries which dissociate to two ground state Ne(+) ions or a ground state Ne atom and Ne(+2) ion. The motivation is to investigate whether there is a minimum in the upper level, the Ne(+2) and Ne level, located in such a way that populations of bound dimer molecules can be built up without dissociating or transitioning to the lower level other than by radiative charge transfer. It is also of interest to show that the ground state is dissociative, that is that its energy is monotonically decreasing with increasing nuclear separation. Calculations were completed using programs known as Gaussian-86, and Diatom. Diatom produced excellent results for the He2(+2)test case. Ne2(+2) calculations were not as accurate as He2(+2), but results did indicate that bound upper level states exist which can only undergo charge transfer radiatively. This research computed Neon dimer dication potential energies for nuclear separations from 0.9 to 20 a.u. of Ne2(+2) sigma, pi, and delta states.

Deemer, Roger Alan

1989-12-01

216

Squid detected NMR and MRI at ultralow fields  

DOEpatents

Nuclear magnetic resonance (NMR) signals are detected in microtesla fields. Prepolarization in millitesla fields is followed by detection with an untuned dc superconducting quantum interference device (SQUID) magnetometer. Because the sensitivity of the SQUID is frequency independent, both signal-to-noise ratio (SNR) and spectral resolution are enhanced by detecting the NMR signal in extremely low magnetic fields, where the NMR lines become very narrow even for grossly inhomogeneous measurement fields. MRI in ultralow magnetic field is based on the NMR at ultralow fields. Gradient magnetic fields are applied, and images are constructed from the detected NMR signals.

Clarke, John (Berkeley, CA); Pines, Alexander (Berkeley, CA); McDermott, Robert F. (Monona, WI); Trabesinger, Andreas H. (London, GB)

2008-12-16

217

Squid detected NMR and MRI at ultralow fields  

DOEpatents

Nuclear magnetic resonance (NMR) signals are detected in microtesla fields. Prepolarization in millitesla fields is followed by detection with an untuned dc superconducting quantum interference device (SQUID) magnetometer. Because the sensitivity of the SQUID is frequency independent, both signal-to-noise ratio (SNR) and spectral resolution are enhanced by detecting the NMR signal in extremely low magnetic fields, where the NMR lines become very narrow even for grossly inhomogeneous measurement fields. MRI in ultralow magnetic field is based on the NMR at ultralow fields. Gradient magnetic fields are applied, and images are constructed from the detected NMR signals.

Clarke, John (Berkeley, CA); McDermott, Robert (Louisville, CO); Pines, Alexander (Berkeley, CA); Trabesinger, Andreas Heinz (CH-8006 Zurich, CH)

2007-05-15

218

Effects of Storage Temperature on the Quality of Frozen Squid  

NASA Astrophysics Data System (ADS)

Squid ( Todarodes pacificus) , which is one of the main Japanzse coastal fish , was frozen under commercial condition after catch immediately and stored at -18 , -23 , -30 °C and 40 °C for 12 months. During storage the quality was measured by determining amount of free drip , water-holding capacity of muscle , weight ratio of cooking loss , histoligical feature of frozen and thawed muscle , and organoleptic test at regular intervals , each 2 months. Storage life of frozen squid was 12 months at below -18 °C.

Kozima, Tsuneo; Ohtaka, Tateo

219

NEON: Transforming Environmental Data into Free, Open Information  

NASA Astrophysics Data System (ADS)

The National Ecological Observatory Network (NEON) will collect data across the United States on the impacts of climate change, land use change and invasive species on natural resources and biodiversity. NEON is a project of the U.S. National Science Foundation (NSF), with many other U.S. agencies and NGOs cooperating. The Observatory’s construction plans call for 60 sites distributed across 20 ecoclimatic Domains. Data will be collected from strategically selected sites within each Domain and synthesized into information products that can be used to describe changes in the nation’s ecosystem through space and time. Sites are arrayed across different land-use types in order to understand large-scale environmental drivers affect biodiversity, ecohydrology, biogeochemistry, and disease ecology across the US continent. NEON is an instrument that listens to the pulse of the US continental ecosystem: infrastructure deployed at these sites will collect an average of over 500 primary measurements at each site, including annual high-resolution airborne LiDAR and hyperspectral data. These primary measurements will be transformed by a state-of-the-art cyberinfrastruture into over 100 higher-order data products. All measurements, data products, algorithms used to compute the data products, and protocols used to collect the primary measurements will be freely available to the public and assessable over the internet. The information products, including selected socio-economic datasets from cooperating Federal agencies, will be served in standard formats, grid-sizes, and geographical projections. This type of information is anticipated to have a wide range of uses, including ecological forecasting, education, public engagement, socio-economic analyses, decision support for climate-change adaptation and mitigation, resource management, and environmental risk management. Open data, interoperability, an open and integrated observation infrastructure, public engagement, and a deliberate approach to making sure that research data can be repurposed for operational purposes are the cornerstones of the NEON strategy: they facilitate the repurposing of credible, reliable data and information for multiple purposes. Often, the same data is useful in an undergraduate course on correlations as it is for public discourse on the effects of increased precipitation on stream water quality. This suggests a strategy for evolving an ecosystem of institutions whose primary responsibility is contributing to an open information commons that creates and curates credible sources of data and information products with clearly documented provenance, quality protocols, uncertainty estimates, and other qualitative descriptors. This information commons is deliberately designed to be tapped by another ecosystem of institutions whose individual missions revolve around some combination of discovery (e.g. research, forecasting, innovation), learning (e.g. public engagement, informal and formal learning, education research), and solutions (e.g. science and technology policy). This talk explores how the NEON information commons is envisioned to interact with this other community of institutions, and how the cornerstone principles enable that community to better focus their creative capabilities around their respective core missions.

Wee, B.

2010-12-01

220

Laser ablation of silicon in neon gas: Study of excitation mechanism of neon neutrals by ablated silicon ions  

SciTech Connect

The excitation mechanism of buffer gas in the laser-ablation process was investigated by time- and space-resolved emission spectroscopies. A silicon disk was ablated in neon gas at a pressure of 1 torr by the fundamental beam output of a Nd: yttrium aluminum garnet laser (1064 nm). The time-resolved emission spectra showed the generation of excited silicon ions Si{sup n+}*(n=1-3) and excited neon neutrals Ne* to the 2p{sub 1} level immediately after laser irradiation. Excitation of Ne to the 2p{sub n}(n=2-10) levels was delayed by 150 ns. The temporal evolutions of the space-resolved emission from Ne* indicated excitation by fast (<100 ns) and/or slow (<300 ns) processes. The slow process contributed to all 2p{sub n} levels, while the fast process was observed only in excitation to the 2p{sub 1} level. This means that the fast process involves level-selective excitation. Based on temporal evolutions, the energy levels, and the collision cross sections of Ne and Si{sup n+}, we assigned the fast and slow processes to excitations by electronic-to-electronic energy transfer from Si{sup 2+}* and translational-to-electronic energy transfer from Si{sup +}, respectively.

Saeki, Morihisa; Hirata, Kohichi; Sakka, Tetsuo; Ohba, Hironori; Yokoyama, Atsushi [Department of Materials Science, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011 (Japan); Department of Materials Science, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan)

2005-08-15

221

Predicting helium and neon adsorption and separation on carbon nanotubes by Monte Carlo simulation.  

PubMed

The adsorption of helium and neon mixtures on single-walled carbon nanotubes (SWCNTs) was investigated at various temperatures (subcritical and supercritical) and pressures using canonical Monte Carlo (CMC) simulation. Adsorption isotherms were obtained at different temperatures (4, 40, 77 and 130 K) and pressures ranging from 1 to 16 MPa. Separation factors and isosteric enthalpies of adsorption were also calculated. Moreover, the adsorption isotherms were obtained at constant specific temperatures (4 and 40 K) and pressures (0.2 and 1.0 MPa) as a function of the amount adsorbed. All of the adsorption isotherms for an equimolar mixture of helium and neon have a Langmuir shape, indicating that no capillary condensation occurs. Both the helium and the neon adsorption isotherms exhibit similar behavior, and slightly more of the helium and neon mixture is adsorbed on the inner surfaces of the SWCNTs than on their outer surfaces. More neon is adsorbed than helium within the specified pressure range. The data obtained show that the isosteric enthalpies for the adsorption of neon are higher than those for helium under the same conditions, which means that adsorption of neon preferentially occurs by (15, 15) SWCNTs. Furthermore, the isosteric enthalpies of adsorption of both gases decrease with increasing temperature. PMID:20559855

Bolboli Nojini, Zabiollah; Abbas Rafati, Amir; Majid Hashemianzadeh, Seyed; Samiee, Sepideh

2011-04-01

222

Fruit Fly Phlebotomy  

NSDL National Science Digital Library

The tiny fruit fly is a popular guinea pig for genetic research but just try strapping one of them down for a blood sample. Until now, researchers have had to squeeze dozens of flies at once to get enough blood to study. But now, scientists at the University of Illinois at Chicago have extracted blood from a single fruit fly larva, collecting as little as 50 billionths of a liter with an ultra-thin vacuum tube. Analytical chemist Scott Shippy says the technique could help scientists study human tissue as well, like the retinal cells in the eye.

Science Update (AAAS;)

2008-04-21

223

Mechanism of the tunable structural color of neon tetra  

NASA Astrophysics Data System (ADS)

Many examples of the structural color can be found in butterfly wings, beetle's elytra and bird feathers. Since the color-producing microstructures of these examples mainly consist of stable materials, for example, dried cuticles in insects and keratin and melanin granules in bird feathers, it is impossible to actively change the microstructure. On the other hand, some fish have the tunability in their structural colors. For example, a small tropical fish, neon tetra, has a longitudinal stripe that looks blue-green in the day time, while it changes into deep violet at night. This fact clearly indicates the variability in the microstructure. It is known that the iridophore of the stripe part of neon tetra contains two stacks of thin light-reflecting platelets that are made of guanine crystal. Since the arrangement of the platelets is observed periodic, the stack is thought to cause the structural color through the multilayer thin-film interference. Consequently, the variability in the color is thought to originate from the variation in the distance between the platelets. Two explanations have been proposed so far for the distance variation. Lythoge and Shand considered that the distance is controlled by osmotic pressure that induces the inflow of the water into the iridophore[1]. On the other hand, Nagaishi et al. proposed a different model, called Venetian blind model, in which the inclination angle of the platelets is varied, resulting in the change in the distance[2]. Recently, we have performed detailed optical measurements on the iridophore of neon tetra. We have paid particular attention to the direction of the reflected light, since the Venetian blind model expects that the direction varies with the color change owing to the tilt of the platelets. We present the experimental results and quantitatively discuss the validity of the Venetian blind model. [4pt] [1] J. N. Lythgoe, and J. Shand, J Physiol. 325, 23-34 (1982). [0pt] [2] H. Nagaishi, N. Oshima, and R. Fujii, Comp. Biochem. Physiol. 95A, 337-341 (1990).

Yoshioka, Shinya

2010-03-01

224

Imaging of the structure of the argon and neon dimer, trimer, and tetramer.  

PubMed

We Coulomb explode argon and neon dimers, trimers, and tetramers by multiple ionization in an ultrashort 800 nm laser pulse. By measuring all momentum vectors of the singly charged ions in coincidence, we determine the ground state nuclear wave function of the dimer, trimer, and tetramer. Furthermore we retrieve the bond angles of the trimer in position space by applying a classical numerical simulation. For the argon and neon trimer, we find a structure close to the equilateral triangle. The width of the distribution around the equilateral triangle is considerably wider for neon than for argon. PMID:21413773

Ulrich, B; Vredenborg, A; Malakzadeh, A; Schmidt, L Ph H; Havermeier, T; Meckel, M; Cole, K; Smolarski, M; Chang, Z; Jahnke, T; Dörner, R

2011-06-30

225

Use of activated charcoal for the purification of neon in the CLEAN experiment  

NASA Astrophysics Data System (ADS)

Passage of neon gas through activated charcoal is planned to be the primary method of removing impurities from the liquid neon scintillator in the CLEAN experiment. In order to quantify this technique, the breakout curves for hydrogen, nitrogen, argon and krypton impurities in neon-saturated activated charcoal were measured. Adsorption coefficients and the number of theoretical stages were measured for hydrogen in the temperature range between 300 and 80 K, nitrogen between 300 and 200 K, and argon between 300 and 190 K. The adsorption coefficient for krypton was measured at 300 K.

Harrison, M. K.; Lippincott, W. H.; McKinsey, D. N.; Nikkel, J. A.

2007-01-01

226

Application of high performance LTS SQUID systems in gravitational experiments  

Microsoft Academic Search

The design of a Galilean-type free-fall experiment to test Einstein's equivalence principle at an improved level of sensitivity is described. Two test bodies of different material fall down from a height of 109 m inside of an evacuated drop tube (Drop Tower Facility Bremen, Germany). Their possible relative displacement is measured using LTS DC SQUID based position sensors. Experiences and

W. Vodel; H. Koch; S. Nietzsche; J. V. Z. Glyscinski; R. Neubert; M. Pilz; H. Dittus; S. Lochmann; C. Mehls; D. Lockowandt

1999-01-01

227

Quality of Squid, 'Illex illecebrosus', Mantles Canned in Oil.  

National Technical Information Service (NTIS)

Squid, Illex illecebrosus, mantles with skin removed were canned in oil, using quarter-pound aluminum sardine cans. The product had a good appearance, a mild flavor, and a firm texture; however, the mantles required blanching prior to canning. Ten minute ...

B. M. Slabyj G. E. Ramsdell R. H. True

1981-01-01

228

Absolute Power Measurement with Transition Edge Sensors and SQUID amplifier  

Microsoft Academic Search

We have developed a new cryogenic radiometer for determining absolute power. This instrument is composed of a superconducting transition edge sensor as a thermometer, a silicon substrate as a heat absorber, and a SQUID amplifier as a readout. The input power is measured with electrical substitution of a heater on the device. By using very sharp transition of the thermometer,

D Fukuda; N Zen; M Ohkubo; K Amemiya; S Kimura; M Ukibe; H Takahashi; M Nakazawa

2006-01-01

229

SQUID readout multiplexers for transition-edge sensor arrays  

Microsoft Academic Search

Two classes of SQUID multiplexer are being developed for large arrays of cryogenic sensors, distinguished by their operation in either the time domain or frequency domain. Several systems optimized for use with Transition-Edge Sensors (TES) are reaching a high level of maturity, and will be deployed on funded astrophysics experiments in the next several years. A useful technical figure of

Adrian T. Lee

2006-01-01

230

Diffuse white structural coloration from multilayer reflectors in a squid.  

PubMed

The white stripes of the pyjama squid (Sepioloidea lineolata) contain multilayer reflectors with an unordered plate arrangement, enabling reflectance of diffuse white light over a range of viewing angles. Ultrastructural analysis and mathematical modeling are employed to elucidate functional mechanisms of diffuse reflectance. This optical system may provide a bio-inspired template for low-energy, reflectance-based synthetic displays. PMID:24789321

Bell, George R R; Mäthger, Lydia M; Gao, Meng; Senft, Stephen L; Kuzirian, Alan M; Kattawar, George W; Hanlon, Roger T

2014-07-01

231

SQUID-based nondestructive evaluation of carbon fiber reinforced polymer  

Microsoft Academic Search

Recent work with HTS SQUIDs in nondestructive evaluation has concentrated on the detection of flaws in aircraft-grade aluminum, with particular emphasis on surface-breaking tears beside rivets. More complex materials are now also being used in aircraft manufacture, with carbon fiber reinforced polymer (CFRP) being one of the most common. Existing technologies such as ultrasound are particularly well suited to the

C. Carr; D. Graham; J. C. Macfarlane; G. B. Donaldson

2003-01-01

232

Redox absorption spectra from single pigment cells of squid.  

PubMed

Single pigment cells from the squid Loligo forbesi have been studied by microspectrophotometry. The absorption spectra obtained show characteristic changes on reduction and oxidation which are compatible with those found in ommochromes. The presence of melanoid substances, however, cannot be excluded. PMID:13635002

BAYER, M; MEYER-ARENDT, J

1959-03-01

233

The winnowing: establishing the squid–vibrio symbiosis  

Microsoft Academic Search

Most symbiotic associations between animals and microorganisms are horizontally transmitted — the microorganisms are acquired from the environment by each generation of the host. How are exclusive partnerships established in the context of the thousands of other microbial species that are present in the environment? Similar to winnowing during a harvest, the symbiosis between the squid Euprymna scolopes and its

Spencer V. Nyholm; Margaret McFall-Ngai

2004-01-01

234

New perspectives on collagen fibers in the squid mantle.  

PubMed

The squid mantle is a complex structure which, in conjunction with a highly sensitive sensory system, provides squid with a wide variety of highly controlled movements. This article presents a model describing systems of collagen fibers that give the mantle its shape and mechanical properties. The validity of the model is verified by comparing predicted optimal fiber angles to actual fiber angles seen in squid mantle. The model predicts optimal configurations for multiple fiber systems. It is found that the tunic fibers (outer collagen layers) provide optimal jetting characteristics when oriented at 31°, which matches empirical data from previous studies. The model also predicted that a set of intramuscular fibers (IM-1) are oriented relative to the longitudinal axis to provide optimal energy storage capacity within the limiting physical bounds of the collagen fibers themselves. In addition, reasons for deviations from the predicted values are analyzed. This study illustrates how the squid's reinforcing collagen fibers are aligned to provide several locomotory advantages and demonstrates how this complex biological process can be accurately modeled with several simplifying assumptions. PMID:22252976

Krieg, Michael; Mohseni, Kamran

2012-06-01

235

High-Tc SQUID Microscopy of Magnetotactic Bacteria  

NASA Astrophysics Data System (ADS)

We present experiments performed on live magnetotactic bacteria (Magnetospirillum magnetotacticum) using a SQUID microscope. Inside a vacuum can, a high-Tc SQUID is mounted on the end of a sapphire rod in thermal contact with a liquid N2 reservoir. A 3?m SiN membrane serves as a vacuum window, 20-30?m above the SQUID. Three layers of mu-metal shield out environmental magnetic fields. Bacteria in growth solution are placed inside a Si well on top of the SiN membrane, where they are detected by the SQUID. Two measurements characterize the bacteria and their dynamics: the magnetic flux noise spectral density due to the motions of the ensemble, and the magnetization of the solution in a uniform magnetic field. Such measurements, carried out on dead bacteria, provide their distributions of sizes and dipole moments. Flux noise data on live bacteria reflect their more complicated dynamics. Features at 25 and 75Hz are vibrations and precessions of the bacteria due to flagellar rotation. Noise at low frequencies is related to the ``run and tumble" motion by which the bacteria swim.

Chemla, Y. R.; Grossman, H. L.; Lee, T. S.; Clarke, John; Adamkiewicz, M.; Buchanan, R.

1998-03-01

236

High-Resolution Displacement Sensor Using a SQUID Array Amplifier  

NASA Technical Reports Server (NTRS)

Improvement in the measurement of displacement has profound implications for both exploration technologies and fundamental physics. For planetary exploration, the new SQUID-based capacitive displacement sensor will enable a more sensitive gravity gradiometer for mapping the interior of planets and moons. A new concept of a superfluid clock to be reported by Penanen and Chui at this workshop is also based on a high-resolution displacement sensor. Examples of high-impact physics projects that can benefit from a better displacement sensor are: detection of gravitational waves, test of the equivalence principle, search for the postulated "axion" particle, and test of the inverse square law of gravity. We describe the concept of a new displacement sensor that makes use of a recent development in the Superconducting Quantum Interference Device (SQUID) technology. The SQUID array amplifier, invented by Welty and Martinis (IEEE Trans. Appl. Superconductivity 3, 2605, 1993), has about the same noise as a conventional SQUID; however, it can work at a much higher frequency of up to 5 MHz. We explain how the higher bandwidth can be translated into higher resolution using a bridge-balancing scheme that can simultaneously balance out both the carrier signal at the bridge output and the electrostatic force acting on the test mass.

Chui, Talso; Penanen, Konstantin; Barmatz, M.; Paik, Ho Jung

2004-01-01

237

Superconducting magnetic shield for high-Tc squid  

Microsoft Academic Search

We describe the processing of the high temperature superconducting magnetic shield and the investigation of its screening properties. The superconducting quantum interference device (SQUID) magnetometer measurements of remnant magnetization clearly show that the magnetic field penetration into the sample starts from low fields. The maximal magnetic field obtained in the frame of Bean critical state model depends on the screen

V. Kantser; L. Konopko; G. Panaitov

1997-01-01

238

High-Tc SQUID magnetometer system with active cancellation  

NASA Astrophysics Data System (ADS)

Recent developments of high-Tc SQUIDs have enabled high sensitivity magnetometers to be used in wide range of places, such as laboratory and outdoor fields. At the early stage of developing multichannel system for measurement of magnetocardiogram (MCG) in clinical application, we have fabricated a single channel high-Tc SQUID magnetometer system. The system includes a direct-coupled SQUID with slot structure, a simple magnetically shielded room (MSR), and some active compensation electronics for the purpose of reducing various environmental field noises. A novel active noise cancellation was made by using a combination of a normal conducting detection coil that was horizontally wound in the middle height of the MSR, and two compensation coils that were wound at the top and bottom of the MSR. In addition, adaptive noise cancellation was supplemented by means of adaptive digital filter that was implemented in a digital signal processor. A total noise field attenuation of 50-60 dB was attained at 0.5-100 Hz. Low noise signals from the human heart were measured with a high-Tc SQUID in the noise reduced space in the MSR. .

Kuriki, S.; Oyama, H.; Hayashi, A.; Washio, T.; Fujita, M.; Hirata, Y.

2002-05-01

239

Vampire squid: detritivores in the oxygen minimum zone  

PubMed Central

Vampire squid (Vampyroteuthis infernalis) are considered phylogenetic relics with cephalopod features of both octopods and squids. They lack feeding tentacles, but in addition to their eight arms, they have two retractile filaments, the exact functions of which have puzzled scientists for years. We present the results of investigations on the feeding ecology and behaviour of Vampyroteuthis, which include extensive in situ, deep-sea video recordings from MBARI's remotely operated vehicles (ROVs), laboratory feeding experiments, diet studies and morphological examinations of the retractile filaments, the arm suckers and cirri. Vampire squid were found to feed on detrital matter of various sizes, from small particles to larger marine aggregates. Ingested items included the remains of gelatinous zooplankton, discarded larvacean houses, crustacean remains, diatoms and faecal pellets. Both ROV observations and laboratory experiments led to the conclusion that vampire squid use their retractile filaments for the capture of food, supporting the hypothesis that the filaments are homologous to cephalopod arms. Vampyroteuthis' feeding behaviour is unlike any other cephalopod, and reveals a unique adaptation that allows these animals to spend most of their life at depths where oxygen concentrations are very low, but where predators are few and typical cephalopod food is scarce.

Hoving, Hendrik J. T.; Robison, Bruce H.

2012-01-01

240

Vampire squid: detritivores in the oxygen minimum zone.  

PubMed

Vampire squid (Vampyroteuthis infernalis) are considered phylogenetic relics with cephalopod features of both octopods and squids. They lack feeding tentacles, but in addition to their eight arms, they have two retractile filaments, the exact functions of which have puzzled scientists for years. We present the results of investigations on the feeding ecology and behaviour of Vampyroteuthis, which include extensive in situ, deep-sea video recordings from MBARI's remotely operated vehicles (ROVs), laboratory feeding experiments, diet studies and morphological examinations of the retractile filaments, the arm suckers and cirri. Vampire squid were found to feed on detrital matter of various sizes, from small particles to larger marine aggregates. Ingested items included the remains of gelatinous zooplankton, discarded larvacean houses, crustacean remains, diatoms and faecal pellets. Both ROV observations and laboratory experiments led to the conclusion that vampire squid use their retractile filaments for the capture of food, supporting the hypothesis that the filaments are homologous to cephalopod arms. Vampyroteuthis' feeding behaviour is unlike any other cephalopod, and reveals a unique adaptation that allows these animals to spend most of their life at depths where oxygen concentrations are very low, but where predators are few and typical cephalopod food is scarce. PMID:23015627

Hoving, Hendrik J T; Robison, Bruce H

2012-11-22

241

Practical DC SQUIDS with extremely low 1\\/F noise  

Microsoft Academic Search

A large number of highly robust and reliable thin film DC SQUIDs have been designed and fabricated which have excellent low frequency noise properties. Measurements performed on isolated devices have yielded a limit on the low frequency (1\\/f) flux noise component which is at least a factor of 60 below the average value reported for devices of this kind. The

C. D. Tesche; K. H. Brown; A. C. Callegari; M. M. Chen; J. H. Greiner; H. C. Jones; M. Ketchen; K. Kim; A. Kleinsasser; H. Notarys; G. Proto; R. Wang; T. Yogi

1985-01-01

242

Venus fly trap  

NSDL National Science Digital Library

Time-lapse photos or video show progressions from the start of an event to the end of the event. These time-lapse photos illustrate the growth of a single Venus fly trap. Biological processes require time.

Paul Lenz (None;)

2006-01-26

243

Instrument Flying Handbook.  

National Technical Information Service (NTIS)

Is an Instrument Rating Necessary. The answer to this question depends entirely upon individual needs. Pilots may not need an instrument rating if they fly in familiar uncongested areas, stay continually alert to weather developments, and accept an altern...

2009-01-01

244

Operation MexFly  

NSDL National Science Digital Library

This activity is an environmental study of the effects of spraying malathion on Mexican fruit flies. In 1990, the city of El Cajon experienced an infestation of Mexican fruit flies, necessitating an aerial spraying of the insecticide malathion. The local community had a varied and wide-spread reaction to the procedure. A colleague and I collaborated to create a series of lessons about the Mexican fruit fly, the insecticide malathion and risk assessment. It was an opportunity to do cross disciplinary teaching, enabling students to see interrelationships between biology, chemistry and local government. The lesson includes background reading for discussion on the Mexican fruit fly, insecticides, and LD-50s. Students complete a short lab on serial dilutions, with risk analysis application problems and a Town Hall meeting to decide if the spraying should take place or develop alternatives.

BEGIN:VCARD VERSION:2.1 FN:Susan E. Emerson N:E. Emerson;Susan ORG:Grossmont High School REV:2005-04-11 END:VCARD

1995-06-30

245

Autonomous Martian flying rover  

NASA Technical Reports Server (NTRS)

A remotely programmable, autonomous flying rover is proposed to extensively survey the Martian surface environment. A Mach .3, solar powered, modified flying wing could cover roughly a 2000 mile range during Martian daylight hours. Multiple craft launched from an orbiting mother ship could provide near-global coverage. Each craft is envisioned to fly at about 1 km above the surface and measure atmospheric composition, pressure and temperature, map surface topography, and remotely penetrate the near subsurface looking for water (ice) and perhaps evidence of life. Data collected are relayed to Earth via the orbiting mother ship. Near surface guidance and control capability is an adaptation of current cruise missile technology. A solar powered aircraft designed to fly in the low temperature, low density, carbon dioxide Martian atmosphere near the surface appears feasible.

1990-01-01

246

Magnetic biosensor using a high transition temperature SQUID  

NASA Astrophysics Data System (ADS)

A high transition temperature (Tc) Superconducting QUantum Interference Device (SQUID) is used to detect magnetically-labeled microorganisms. The targets are identified and quantified by means of magnetic relaxation measurements, with no need for unbound magnetic labels to be washed away. The binding rate between antibody-linked magnetic particles and targets can be measured with this technique. Installed in a "SQUID microscope," a YBa2Cu 3O7-delta SQUID is mounted on a sapphire rod thermally linked to a liquid nitrogen can; these components are enclosed in a fiberglass vacuum chamber. A thin window separates the vacuum chamber from the sample, which is at room temperature and atmospheric pressure. In one mode of the experiment, targets are immobilized on a substrate and immersed a suspension of ˜50 nm diameter superparamagnetic particles, coated with antibodies. A pulsed magnetic field aligns the magnetic dipole moments, and the SQUID measures the magnetic relaxation signal each time the field is turned off. Unbound particles relax within ˜50 mus by Brownian rotation, too fast for the SQUID system to measure. In contrast, particles bound to targets have their Brownian motion inhibited. These particles relax in ˜1 s by rotation of the internal dipole moment, and this Neel relaxation process is detected by the SQUID. This assay is demonstrated with a model system of liposomes carrying the FLAG epitope; the detection limit is (2.7 +/- 0.2) x 105 particles. The replacement of the SQUID with a gradiometer improves the detection limit to (7.0 +/- 0.7) x 103 particles. In an alternate mode of the experiment, freely suspended targets (larger than ˜1 mum diameter) are detected. Since the Brownian relaxation time of the targets is longer than the measurement time, particles bound to targets are effectively immobilized and exhibit Neel relaxation. Listeria monocytogenes are detected using this method; the sensitivity is (1.1 +/- 0.2) x 105 bacteria in 20 muL. For a 1 nL sample volume, the detection limit is expected to be 230 +/- 40 bacteria. Time-resolved measurements, which yield the binding rate between particles and bacteria, are reported. Also, potential improvements to the system and possible applications are discussed.

Grossman, Helene Lila

247

SQUID-detected NMR and MRI in microtesla magnetic fields  

NASA Astrophysics Data System (ADS)

A low transition temperature do Superconducting QUantum Interference Device (low-Tc do SQUID) was used to perform liquid-state nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) experiments in magnetic fields from microtesla to tens of microtesla, corresponding to proton Larmor frequencies from tens of Hz to kHz. The spins were polarized in a magnetic field of the order of millitesla. Upon turnoff of the polarizing field, precession was induced in the much weaker measurement field. Because the SQUID magnetometer was operated with an untuned, superconducting, input circuit, the integrated intensity of the NMR lines was independent of the strength of the measurement field. On the other hand, the NMR linewidth scaled linearly with the measurement field strength. Narrowing of the NMR signal bandwidth through reduction of the strength of the measurement field led to an enhancement of both spectral resolution and signal-to-noise ratio (SNR). A novel cryogenic insert was constructed to allow SQUID measurement of NMR signals from room temperature samples with high filling factor. From samples with volume of a few milliliters and thermal polarization of order 10 -8, SNR of a few tens were achieved in a single shot. Heteronuclear scalar couplings were resolved in 1H-31P and 1H-13C systems. Furthermore, the frequency-independent sensitivity of the untuned SQUID magnetometer allowed simultaneous detection of NMR signals from nuclei with different magnetogyric ratios. A system based on a low-Tc SQUID gradiometer was used to acquire MRIs from distilled water and mineral oil phantoms in microtesla fields. The bandwidth-narrowing technique was exploited to enhance spatial resolution for a fixed strength of the encoding gradients. With magnetic field gradients of the order of tens of microtesla per meter, images with spatial resolution of a millimeter were achieved. The techniques described in this thesis could readily be adapted for use with multichannel SQUID systems designed for biomagnetic measurements at low frequency, and represent a first step toward the development of low cost, portable NMR and MRI scanners based on untuned SQUID magnetometers.

McDermott, Robert Francis

248

Design a Flying Machine  

NSDL National Science Digital Library

The purpose of this activity is for the students to draw a design for their own flying machine. They will apply their knowledge of aircraft design and the forces acting on them. The students will start with a brainstorming activity where they come up with creative uses for every day objects. They will then use their creativity and knowledge of airplanes to design their own flying machine.

Integrated Teaching And Learning Program

249

Water depth measurement using an airborne pulsed neon laser system  

NASA Technical Reports Server (NTRS)

The paper presents the water depth measurement using an airborne pulsed neon laser system. The results of initial base-line field test results of NASA airborne oceanographic lidar in the bathymetry mode are given, with water-truth measurements of depth and beam attenuation coefficients by boat taken at the same time as overflights to aid in determining the system's operational performance. The nadir-angle tests and field-of-view data are presented; this laser bathymetry system is an improvement over prior models in that (1) the surface-to-bottom pulse waveform is digitally recorded on magnetic tape, and (2) wide-swath mapping data may be routinely acquired using a 30 deg full-angle conical scanner.

Hoge, F. E.; Swift, R. N.; Frederick, E. B.

1980-01-01

250

The infrared spectrum of HOOH+ trapped in solid neon  

NASA Astrophysics Data System (ADS)

When a Ne:H2O2 mixture is codeposited at 4.3 K with a beam of neon atoms that have been excited in a microwave discharge, three new, photosensitive absorptions appear which can be assigned to the three infrared-active vibrational fundamentals of trans-HOOH+. When the Ne:H2O2 deposition system is pretreated with the vapors of D2O, the product absorptions include new peaks which can be attributed to vibrational fundamentals of trans-HOOD+ and trans-DOOD+. Density functional calculations of the vibrational fundamentals of the three hydrogen peroxide cation isotopologues support the proposed assignments. Broad, photosensitive product absorptions also appear near the positions of vibrational transitions of O3-, and may be contributed by a weakly bound complex of that species with H2O.

Thompson, Warren E.; Lugez, Catherine L.; Jacox, Marilyn E.

2012-10-01

251

Deformation of silica aerogels during adsorption of helium and neon  

NASA Astrophysics Data System (ADS)

Fluids confined in aerogel, especially ^3He and ^4He, have been intensely studied for over a decade. Because of the low surface tensions of these fluids, capillary forces are small and the resulting deformation of the aerogel is usually neglected. However, high porosity aerogels are very compressible and large volume changes have been seen^1 during adsorption of nitrogen, which has a much higher surface tension. We have used a linear variable differential transformer (LVDT) to measure the deformation of aerogels as fluids capillary condense within them. Our measurements are taken along isotherms near the critical points of neon and helium and show small volume changes in the aerogel during adsorption and desorption. 1. G. Reichenauer and G.W. Scherer, J. Non-Cryst. Solids 277 (2000) 162.

Herman, Tobias; Beamish, John

2004-03-01

252

Solid neon moderated electrostatic or magnetic positron beam  

SciTech Connect

A high intensity variable energy positron beam has been constructed at Brookhaven National Laboratory (BNL). Positrons from a 97mCi {sup 22}Na source are moderated by a thin layer of solid neon. A magnetic guiding system delivered up to 5{times}10{sup 6}e{sup +}/sec to an experiment. Currently tests are under way to facilitate the operation with the magnetic guiding system or -- for other experimental sites -- with an electrostatic beam transport. The electrostatic lenses are fabricated from {mu}-metal. No compensation of the earth magnetic field is required. Several experiments can utilize the beam on a time sharing basis. In the near future the source will be replaced by {sup 64}Cu which has a much higher activity. Beam intensities up to 10{sup 9}e{sup +}/sec are expected.

Weber, M.; Schwab, A. [Bielefeld Univ. (Germany). Fakultaet fuer Physik; Becker, D.; Lynn, K.G. [Brookhaven National Lab., Upton, NY (United States)

1991-12-31

253

Solid neon moderated electrostatic or magnetic positron beam  

SciTech Connect

A high intensity variable energy positron beam has been constructed at Brookhaven National Laboratory (BNL). Positrons from a 97mCi {sup 22}Na source are moderated by a thin layer of solid neon. A magnetic guiding system delivered up to 5{times}10{sup 6}e{sup +}/sec to an experiment. Currently tests are under way to facilitate the operation with the magnetic guiding system or -- for other experimental sites -- with an electrostatic beam transport. The electrostatic lenses are fabricated from {mu}-metal. No compensation of the earth magnetic field is required. Several experiments can utilize the beam on a time sharing basis. In the near future the source will be replaced by {sup 64}Cu which has a much higher activity. Beam intensities up to 10{sup 9}e{sup +}/sec are expected.

Weber, M.; Schwab, A. (Bielefeld Univ. (Germany). Fakultaet fuer Physik); Becker, D.; Lynn, K.G. (Brookhaven National Lab., Upton, NY (United States))

1991-01-01

254

Paleointensity of the Martian field from SQUID Microscopy  

NASA Astrophysics Data System (ADS)

Crustal magnetic anomalies in the southern Martian hemisphere have intensities an order of magnitude larger than typical crustal anomalies on Earth. Two possible explanations for this difference are that compared to the present-day Earth, Mars has either (i) larger amounts of crustal ferromagnetic minerals or (ii) the crust was magnetized by a larger paleofield. ALH84001, the only pre-Amazonian Martian meteorite, possesses a stable magnetization dating to 4 Ga or earlier. Previous paleomagnetic studies with SQUID moment magnetometers on bulk ALH84001 grains have estimated that the paleointensity of the field which magnetized the meteorite was between 0.1-1 times that of the Earth's present field. However, these estimates may be lower limits on the true paleointensity because the orientation of the magnetization in ALH84001 is spatially heterogeneous on the submillimeter scale. This complication could have profound implications for hypothesis (ii) above. Here we first demonstrate that superconducting quantum interference device (SQUID) microscopy can recover the same magnetization intensity and direction of a well characterized modern-day terrestrial basalt as that measured with a 2G Enterprises SQUID moment magnetometer. A SQUID microscope paleointensity analysis of this basalt gives the expected present day field intensity of a few tens of microtesla. We further show that our new high resolution SQUID microscopy study of ALH84001, which has mapped its heterogeneous magnetization with the highest resolution yet (0.1 mm), favors the upper range of previous paleointensity estimates for the 4 Ga Martian paleofield (e.g., within a factor of several of that of the present-day Earth). However, this field, were it dynamo in origin, is still too weak to easily explain the intensity of the Martian magnetic anomalies.

Weiss, B. P.; Fong, L. E.; Lima, E. A.; Baudenbacher, F. J.; Vali, H.

2005-12-01

255

SQUID Microscopy: Magnetic Images of Room Temperature Samples  

NASA Astrophysics Data System (ADS)

We use a microscope based on a high-Tc Superconducting Quantum Interference Device (SQUID) to study room temperature samples. The SQUID, which measures magnetic flux, is mounted on a sapphire rod and maintained at 77 K inside a vacuum chamber. A sample, separated from the vacuum chamber by a window, is placed above the SQUID, and the entire microscope is enclosed within a magnetic shield. The sample can be scanned over the SQUID to obtain a magnetic image. We have used the microscope to study magnetotactic bacteria, which have a permanent magnetic dipole moment of about 1.5 x 10-16 Am^2. The bacteria, suspended in an aqueous medium, are placed in a cell which is separated from the vacuum chamber by a 3 micron thick SiN membrane. The sample is brought as close as 15 micron to the SQUID, and the magnetic flux noise from the motion of the bacteria is measured. Data from non-motile cells, which undergo Brownian motion, give us information about the distribution of lengths of the bacteria. By applying a magnetic field, we can determine the average dipole moment. Noise measurements of the live bacteria give us the rates of flagellar rotation and body-roll, as well as the amplitudes of the vibrational and precessional motions. Another application of the microscope is non-destructive evaluation of steel. We have investigated the effects of both thermal and mechanical stresses on the remnant magnetization of steel. A third application of the microscope is in studying the properties of ferromagnetic nanocrystals of Co and Fe_3O_4.

Grossman, Helene

1998-10-01

256

The Microstrip SQUID Amplifier: Searching for the Axion  

NASA Astrophysics Data System (ADS)

The axion detector [1] at LLNL requires a very low noise amplifier in the 1-GHz frequency range. In the first generation detector, the cavity was cooled to 1.5 K and the amplifier was a HEMT (High Electron Mobility Transistor) with a noise temperature TN of 1.7 K. Thus, the system noise temperature Ts was 3.2 K. In an attempt to achieve significantly lower noise temperatures, we fabricated amplifiers based on the dc SQUID [2] (Superconducting QUantum Interference Device). The theory [3] for SQUID amplifiers with a resonant input circuit predicts that an optimized device at sufficiently low temperatures should be quantum limited, that is, TN = hf/k at frequency f. To extend the operating frequency to the gigahertz range, we developed the Microstrip SQUID Amplifier (MSA) in which the input coil forms a microstrip with the SQUID washer [4, 5]. When the length of the coil corresponds to a half-wavelength of the signal, the gain is typically 20 dB. We measured the gain and noise [6] of an MSA in which the resistive shunts of the junctions were coupled to cooling fins to reduce hot electron effects [7]. At 0.62 GHz, we achieved a minimum noise temperature TN = 48+/-5mK for a bath temperature of 50 mK and at a frequency below resonance, as predicted. The quantum limit is 30 mK. Since the time for the axion detector to scan a given frequency range scales as Ts2, replacing the HEMT with a SQUID and cooling the cavity to 50 mK potentially reduces the scan time by three orders of magnitude.

Clarke, John

2009-12-01

257

Design, optimization and construction of a dc-SQUID with complete flux transformer circuits  

NASA Astrophysics Data System (ADS)

The design of a complete dc Superconducting Quantum Interference Device (SQUID) with a flux transformer input circuit is described. The flux coupling circuits introduce a substantial capacitance across the SQUID and give rise to many resonances which may couple strongly to the SQUID dynamics. Both effects lead to multiple modes in the SQUID dynamics and, consequently, to excess noise. For a low-noise SQUID with smooth characteristics, the analysis and practical considerations suggest signal coupling via an intermediary transformer. The method allows simultaneous optimization of the SQUID parameters, minimizing the parasitic capacitance, control over the resonances, and good inductance matching to practical magnetometer coils. A model is developed to optimize the structure; it describes the whole circuit with the help of a suitably modified autonomous SQUID, provided that the system is free from multiple modes due to resonances or large parasitic capacitance. Following these design principles, a dc SQUID was built. The fabrication of the SQUID and the high-quality electronics especially suitable for multiple-SQUID devices is presented.

Knuutila, J.; Kajola, M.; Seppae, H.; Multikainen, R.; Salmi, J.

1987-10-01

258

Development of Robust HTS-SQUID for Non-destructive Inspection System in Unshielded Environment  

NASA Astrophysics Data System (ADS)

Cross-shaped YBa2Cu3O7?x (YBCO) film was overlapped on directly-coupled multi-pickup-coil HTS-dc-SQUID magnetometer in flip-chip configuration as a superconducting shield, and the characterestics of the SQUID were examined in DC and AC magnetic fields. We created slots in the YBCO film and pickup-coil of HTS-SQUID magnetometer for suppression of flux trapping. In low magnetic field environment, we measured the characteristics of the SQUID without and with HTS film. The most of the parameters were same with and without the HTS films, while S1/2phi with the HTS film was a bit smaller than that of the bare SQUID. In the DC field, Ic of the HTS-SQUID covered with the HTS film did not change until a DC field over 140 ?T was applied to the SQUID, while the bare SQUID's Ic decreased with the increase of the applied DC field. In the AC fields at 10 MHz, the SQUID with the HTS film showed degradation of the parameters such as Vpp and S12phi at lower field amplitude than the bare SQUID.

Yoshida, K.; Kage, T.; Suzuki, T.; Hatsukade, Y.; Tanaka, S.

2014-05-01

259

Erosion in the DIII-D divertor by neon-detached plasmas  

NASA Astrophysics Data System (ADS)

We report the first measurements of erosion of divertor materials by plasmas detached by neon injection. Neon injection cooled the plasma edge by radiation, reduced the temperature and increased the density of the divertor plasma, and reduced the peak heat flux onto the divertor plate, while maintaining good H-mode energy confinement and purity of core plasma. The rate of carbon erosion at the outer strike point was very high (˜15 nm/s), in contrast to the absence of erosion from plasmas detached by deuterium injection observed in previous experiments. The erosion rate for tungsten and vanadium remained low for neon-detached plasma. A likely cause of the high net carbon erosion rate is physical sputtering by neon, chemically enhanced by the formation of hydrocarbons.

Wampler, W. R.; Whyte, D. G.; Wong, C. P. C.; West, W. P.

2003-03-01

260

Effects of Basis Set Contraction in Relativistic Calculations on Neon, Argon and Germanium.  

National Technical Information Service (NTIS)

Calculations on neon, argon, and germanium have been performed with basis sets of contracted and uncontracted Gaussian-type functions. Both relativistic and non-relativistic Hartree-Fock and many-body perturbation theory calculations have been performed w...

Y. Ishikawa H. Sekino R. C. Binning

1990-01-01

261

Laser optogalvanic wavelength calibration with a commercial hollow cathode iron - neon discharge lamp  

NASA Technical Reports Server (NTRS)

351 optogalvanic transitions have been observed in the 337 - 598 nm wavelength region using an iron - neon hollow cathode discharge lamp and a pulsed tunable dye laser. 223 of these have been identified as transitions associated with neon energy levels. These optogalvanic transitions have allowed, in conjunction with interference fringes recorded concomitantly with an etalon, the calibration of the dye laser wavelength with 0.3/cm accuracy.

Zhu, Xinming; Nur, Abdullahi H.; Misra, Prabhakar

1994-01-01

262

Production of nucleogenic neon in the Earth from natural radioactive decay  

Microsoft Academic Search

Nucleogenic neon isotope production resulting from alpha decay of naturally occurring U and Th was calculated for typical compositions of the mantle and crust using a simple non-Monte Carlo code for neutron transport. The (alpha,n), (alpha,p), and (n,alpha) reactions, leading to the production of neon isotopes in the outgoing reaction channel, are taken into account in the calculations. In the

Igor Yatsevich; Masahiko Honda

1997-01-01

263

Preservation of near-solar neon isotopic ratios in Icelandic basalts  

Microsoft Academic Search

Neon isotopic ratios measured in olivine and basaltic glass from Iceland are the most primitive observed so far in terrestrial mantle-derived samples. Ratios were measured in gas released from olivine and basaltic glass from a total of 10 samples from the Reykjanes Peninsula, Iceland, and one sample from central Iceland. The neon isotopic ratios include solar-like, mid-ocean ridge basalt (MORB)-like

Eleanor T. Dixon; Masahiko Honda; Ian McDougall; Ian H. Campbell; Ingvar Sigurdsson

2000-01-01

264

X-ray diffraction and equation of state of solid neon to 110 GPa  

Microsoft Academic Search

Solid neon was compressed under static conditions at 300 K to pressures in the 100 GPa (megabar) range using diamond-anvil cell techniques. The crystal structure and P-V equation of state were determined by energy-dispersive x-ray diffraction with microcollimated synchrotron radiation. Pressures were determined from ruby fluorescence spectra and from x-ray diffraction of tungsten powder contained within the sample. Solid neon

R. J. Hemley; C. S. Zha; A. P. Jephcoat; H. K. Mao; L. W. Finger; D. E. Cox

1989-01-01

265

Emission anomalous optical magnetic resonances in a mixture of even neon isotopes  

SciTech Connect

Unusual resonances have been detected in the dependence of the discharge glow in neon on the longitudinal magnetic field. The resonances appear in fairly high magnetic fields and are observed only at low gas pressures and exclusively in a mixture of {sup 20}Ne and {sup 22}Ne isotopes. This phenomenon is an evidence of collective resonant radiation processes involving atoms of different neon isotopes.

Saprykin, E. G.; Sorokin, V. A., E-mail: Vlad_sorokin@ngs.ru; Shalagin, A. M. [Siberian Branch, Russian Academy of Sciences, Institute of Automation and Electrometry (Russian Federation)

2013-04-15

266

Method and apparatus for cooling high temperature superconductors with neon-nitrogen mixtures  

DOEpatents

Apparatus and methods for cooling high temperature superconducting materials (HTSC) to superconductive temperatures within the range of 27.degree. K. to 77.degree. K. using a mixed refrigerant consisting of liquefied neon and nitrogen containing up to about ten mole percent neon by contacting and surrounding the HTSC material with the mixed refrigerant so that free convection or forced flow convection heat transfer can be effected.

Laverman, Royce J. (South Holland, IL); Lai, Ban-Yen (Hinsdale, IL)

1993-01-01

267

Monte Carlo simulations of neon versus helium ion beam induced deposition, sputtering and etching  

NASA Astrophysics Data System (ADS)

The ion beam induced nanoscale synthesis of PtCx (where x ˜ 5) using the trimethyl (methylcyclopentadienyl)platinum(IV) (MeCpPt^IVMe3) precursor is investigated by performing Monte Carlo simulations of helium and neon ions. The helium beam leads to more lateral growth relative to the neon beam because of its larger interaction volume. The lateral growth of the nanopillars is dominated by molecules deposited via secondary electrons in the both simulations. Notably, the helium pillars are dominated by SE-I electrons whereas the neon pillars by SE-II electrons. Using a low precursor residence time of 70?s resulting in an equilibrium coverage of ˜ 4%, the neon simulation has a lower deposition efficiency (3.5%) compared to that of the helium simulation (6.5%). At larger residence time (10ms) and consequently larger equilibrium coverage (85%) the deposition efficiencies of helium and neon increased to 49% and 21%, respectively; which is dominated by increased lateral growth rates leading to broader pillars. The nanoscale growth is further studied by varying the ion beam diameter at 10 ms precursor residence time. The study shows that total SE yield decreases with increasing beam diameters for the both ion types. However, the helium has the larger SE yield as compared to that of neon in the both low and high precursor residence time, and thus pillars are wider in all the simulations studied.

Timilsina, Rajendra; Smith, Daryl; Rack, Philip

2013-03-01

268

A comparison of neon versus helium ion beam induced deposition via Monte Carlo simulations  

NASA Astrophysics Data System (ADS)

The ion beam induced nanoscale synthesis of PtCx (where x ˜ 5) using the trimethyl (methylcyclopentadienyl)platinum(IV) (MeCpPtIVMe3) precursor is investigated by performing Monte Carlo simulations of helium and neon ions. The helium beam leads to more lateral growth relative to the neon beam because of its larger interaction volume. The lateral growth of the nanopillars is dominated by molecules deposited via secondary electrons in both the simulations. Notably, the helium pillars are dominated by SE-I electrons whereas the neon pillars are dominated by SE-II electrons. Using a low precursor residence time of 70 ?s, resulting in an equilibrium coverage of ˜4%, the neon simulation has a lower deposition efficiency (3.5%) compared to that of the helium simulation (6.5%). At larger residence time (10 ms) and consequently larger equilibrium coverage (85%) the deposition efficiencies of helium and neon increased to 49% and 21%, respectively; which is dominated by increased lateral growth rates leading to broader pillars. The nanoscale growth is further studied by varying the ion beam diameter at 10 ms precursor residence time. The study shows that total SE yield decreases with increasing beam diameters for both the ion types. However, helium has the larger SE yield as compared to that of neon in both the low and high precursor residence time, and thus pillars are wider in all the simulations studied.

Timilsina, Rajendra; Smith, Daryl A.; Rack, Philip D.

2013-03-01

269

Some phenomena due to SQUID input properties when local feedback is present  

NASA Astrophysics Data System (ADS)

We have constructed a two-stage SQUID amplifier, in which series-mixing local feedback has been used to screen the SQUID input inductances and hence to boost the power gain of the amplifier. 2.9 pA/Hz1/2 current noise and 2.9 nH input inductance of the lower SQUID stage imply energy resolution of 18 times Planck constant at 4.2 K, which, arguably, can be further improved by input inductance screening. The upper stage consists of a 184-series 4-parallel SQUID array, which, when used alone, shows lower than 0.03 ??0/Hz2 flux noise, but which as a part of the two-stage amplifier is operated at a higher flux noise level to provide robust, EMI-tolerant output signal. The series-mixing feedback also facilitates negative SQUID input impedance, which would allow self-oscillating SQUID-based frequency domain multiplexing.

Kiviranta, Mikko; Grönberg, Leif; Beev, Nikolai; van der Kuur, Jan

2014-05-01

270

Autonomous Flying Controls Testbed  

NASA Technical Reports Server (NTRS)

The Flying Controls Testbed (FLiC) is a relatively small and inexpensive unmanned aerial vehicle developed specifically to test highly experimental flight control approaches. The most recent version of the FLiC is configured with 16 independent aileron segments, supports the implementation of C-coded experimental controllers, and is capable of fully autonomous flight from takeoff roll to landing, including flight test maneuvers. The test vehicle is basically a modified Army target drone, AN/FQM-117B, developed as part of a collaboration between the Aviation Applied Technology Directorate (AATD) at Fort Eustis,Virginia and NASA Langley Research Center. Several vehicles have been constructed and collectively have flown over 600 successful test flights.

Motter, Mark A.

2005-01-01

271

Flies and the mouth.  

PubMed

Oral infections caused by flies are rarely encountered in clinical practice, and consequently, there is a paucity of information in the medical and dental literature about these conditions. In the present article, we present a concise review on oral myiasis or fly-blown disease. A variety of fly species can infest the oral tissues and produce an exotic clinical picture. Oral myiasis is mainly encountered in the tropics and subtropics, but can also be encountered in the western part of the world due to the increase of globalization, immigration, and global warming. Commonly-reported symptoms of oral myiasis include pain, swelling, itchy sensation, and feeling of something moving in the mouth. The surgical debridement of infected tissue with the removal of maggots is the treatment of choice in most cases of oral myiasis. PMID:24574273

Hassona, Yazan; Scully, Crispian; Aguida, Miranda; de Almeida, Oslei Paes

2014-05-01

272

Single fly tethered paradigms.  

PubMed

The most successful approaches for studying visual perception and visual learning in Drosophila have been single fly paradigms in which tethered individuals respond to different visual stimuli, as described here. The equipment and protocols involved are quite sophisticated and differ depending on whether behavior or electrophysiology will be pursued. For either approach, flies must first be secured to a metal wire. This is typically performed by first cooling flies down to 4°C and then gluing them to a copper or tungsten wire with ultraviolet (UV)-activated cement. For electrophysiology, tethering requires a few extra steps to accommodate the placement of electrodes. Prepared individuals are then placed inside a cylindrical arena where images can be presented, or in front of a computer screen or even in front of a laptop. Flight dynamics or brain activity in response to visual stimuli is recorded by using a variety of specialized and/or commercially available electronic devices. PMID:22135659

van Swinderen, Bruno

2011-12-01

273

Low pressure broadening and shift of the 2 p 5 3 p -2 p 5 6 s neon spectral lines  

Microsoft Academic Search

The broadening and shift of four spectral lines arising from the 2p53p-2p56s transitions of neon emitted from a low pressure glow discharge in pure neon and a neon-helium mixture have been measured. The values of the pressure broadening and shift coefficients are determined. The results are interpreted in terms of the impact theory assuming the Lennard-Jones potential. Results obtained in

A. Bielski; K. Bryl; W. Dokurno; E. Lisicki

1981-01-01

274

Dc and un-SQUIDs for readout of ac-biased transition-edge sensors  

Microsoft Academic Search

We have developed a set of SQUIDs optimized for readout of ac-biased transition edge sensors. Junction shunts are made of Pd and attached to cooling fins to facilitate low-noise operation at sub-kelvin temperatures. SQUID's have a low loop inductance in order to reach a large natural dynamic range even without negative feedback. The SQUIDs are intended to be used for

Mikko Kiviranta; Jari S. Penttilä; Leif Grönberg; Heikki Seppä; Ilkka Suni

2003-01-01

275

Investigation of Low-Frequency Excess Flux Noise in DC SQUIDs at mK Temperatures  

Microsoft Academic Search

The excess low-frequency flux noise in dc super- conducting quantum interference devices (SQUIDs) operated at ultra-low temperatures was studied. A large number of single SQUIDs as well as SQUID arrays from 16 wafers fabricated over a period of six years were characterized at 4.2 K and 320 mK. Considering the large spread in the low-frequency noise at 4.2 K, there

Dietmar Drung; Jörn Beyer; Jan-Hendrik Storm; Margret Peters; Thomas Schurig

2011-01-01

276

Operation of HTS dc-SQUID sensors in high magnetic fields  

Microsoft Academic Search

For HTS dc-SQUID sensors operating in high magnetic fields we have used quasiplanar HTS Josephson junctions, HTS films prepared at optimized conditions with a high oxygen pressure dc-sputtering technique, a capsulation with a heater, and a proper dc-SQUID layouts. DC-SQUIDs tested in magnetic fields up to about 1 kG demonstrate no reduction of the critical current. A model is proposed,

M. I. Faley; U. Poppe; K. Urban; E. Zimmermann; W. Glaas; H. Halling; M. Bick; H.-J. Krause; D. N. Paulson; T. Starr; R. L. Fagaly

1999-01-01

277

Study on nondestructive inspection using HTS-SQUID for friction stir welding between dissimilar metals  

Microsoft Academic Search

We have developed an SQUID-NDI technique for evaluation of friction stir welding (FSW) between aluminum alloy A6063 and stainless steel SUS304 from the electric conductivities in board specimens bonded by FSW. A SQUID-NDI system employing an HTS-SQUID gradiometer was constructed to measure current distribution in the FSW specimens by applying voltage to the specimen. By measuring field gradients dBz\\/dy and

Y. Hatsukade; T. Takahashi; T. Yasui; M. Tsubaki; M. Fukumono; S. Tanaka

2007-01-01

278

Apparatus for detecting a magnetic anomaly contiguous to remote location by SQUID gradiometer and magnetometer systems  

SciTech Connect

A superconducting quantum interference device (SQUID) magnetic detection apparatus detects magnetic fields, signals, and anomalies at remote locations. Two remotely rotatable SQUID gradiometers may be housed in a cryogenic environment to search for and locate unambiguously magnetic anomalies. The SQUID magnetic detection apparatus can be used to determine the azimuth of a hydrofracture by first flooding the hydrofracture with a ferrofluid to create an artificial magnetic anomaly therein.

Overton, W.C. Jr.; Steyert, W.A. Jr.

1984-03-13

279

Liquid helium cryostat for SQUID-based MRI receivers  

NASA Astrophysics Data System (ADS)

We describe a liquid helium cryostat, developed to cool SQUID-based receivers in low field MRI systems. The cryostat has a 4 L liquid helium capacity, a hold time of over 3 days and accommodates 10 cm diameter receiver coils. New vacuum insulation methods reduce the noise level by at least an order of magnitude compared to existing commercial designs. The minimum detectable field at 425 kHz, with a 5 cm diameter circular coil, was estimated to be 0.018 fT/Hz 1/2 from Q-factor measurements and 0.035 fT/Hz 1/2 by direct measurement with a SQUID amplifier. Further measurements indicated that most of this field noise probably originates with dielectric losses in the cryostat's fibreglass shells.

Seton, H. C.; Hutchison, J. M. S.; Bussell, D. M.

2005-05-01

280

Reducing systematic errors in measurements made by a SQUID magnetometer  

NASA Astrophysics Data System (ADS)

A simple method is described which reduces those systematic errors of a superconducting quantum interference device (SQUID) magnetometer that arise from possible radial displacements of the sample in the second-order gradiometer superconducting pickup coil. By rotating the sample rod (and hence the sample) around its axis into a position where the best fit is obtained to the output voltage of the SQUID as the sample is moved through the pickup coil, the accuracy of measuring magnetic moments can be increased significantly. In the cases of an examined Co1.9Fe1.1Si Heusler alloy, pure iron and nickel samples, the accuracy could be increased over the value given in the specification of the device. The suggested method is only meaningful if the measurement uncertainty is dominated by systematic errors - radial displacement in particular - and not by instrumental or environmental noise.

Kiss, L. F.; Kaptás, D.; Balogh, J.

2014-11-01

281

Medical applications of SQUIDs in neuro- and cardiomagnetism  

NASA Astrophysics Data System (ADS)

Magnetoencephalography (MEG) and magnetocardiography (MCG) are two completely non-invasive imaging techniques, suitable for basic and clinical studies of human subjects. Large SQUID arrays, operating at liquid helium temperatures, are employed for detecting and localizing magnetically the active regions, modelled by current dipoles, in the working brain or heart. The measurements must be performed in magnetically shielded rooms. Time resolution of both methods is 0.5 ms and spatial accuracy 5-6mm. Commercial multi-SQUID instruments are now available from several manufacturers. An adequate account of the theory and practice of both techniques is given. Three examples of brain studies and two investigations of the heart are described. The advantages and drawbacks of modern imaging techniques, including MRI and PET, are compared and the future of MEG and MCG is discussed.

Lounasmaa, Olli V.

1996-01-01

282

Establishment of 37 channel SQUID system for magnetocardiography  

NASA Astrophysics Data System (ADS)

We report the development of a thirty seven channel SQUID based Magnetocardiography (MCG) system for the measurement of biomagnetic fields originating from the human heart. These fields are extremely weak and can be non-invasively measured only by using SQUID sensors. The system can simultaneously record biomagnetic signals at thirty seven spatial locations on the chest with a total coverage area of 300 cm2. The typical noise level of the system is measured to be about 2.5 fTrms/cm/?Hz for most gradiometer channels and around 7.3 fTrms/?Hz for magnetometer channels. The measurement of Magnetocardiogram (MCG) from human heart carried out using this system is shown.

Parasakthi, C.; Patel, Rajesh; Sengottuvel, S.; Mariyappa, N.; Gireesan, K.; Janawadkar, M. P.; Radhakrishnan, T. S.

2012-06-01

283

Low noise LTS SQUIDs for application in gravitational experiments  

Microsoft Academic Search

The Weak Principle of Equivalence (WEP) is proved up to now with an accuracy of 1×10-12. Short range free fall experiments attained an accuracy of 5×10-10 only. Microgravity facilities such as the “Drop Tower Bremen” enables long range free fall experiments which may improve the accuracy of free fall tests to <10-12 using high performance SQUID measuring technique. In this

W. Vodel; H. Koch; S. Nietzsche; J. V. Zameck Glyscinski; H. Dittus; S. Lochmann; C. Mehls

1997-01-01

284

ASSOCIATION OF CALCIUM WITH MEMBRANES OF SQUID GIANT AXON  

PubMed Central

Giant axons from the squid, Loligo pealei, were fixed in glutaraldehyde and postfixed in osmium tetroxide. Calcium chloride (5 mM/liter) was added to all aqueous solutions used for tissue processing. Electron-opaque deposits were found along the axonal plasma membranes, within mitochondria, and along the basal plasma membranes of Schwann cells. X-ray microprobe analysis (EMMA-4) yielded signals for calcium and phosphorus when deposits were probed, whereas these elements were not detected in the axoplasm.

Oschman, J. L.; Hall, T. A.; Peters, P. D.; Wall, B. J.

1974-01-01

285

PERMEABILITY OF SQUID AXON MEMBRANE TO VARIOUS IONS  

Microsoft Academic Search

The permeability of the squid axon membrane to Na²², Br⁸², ; Rb⁸⁶, Cs¹³⁴, and Cs¹³⁷ was determined. Effluxes of these ; isotopes were measured mainly by the method of intracellular injection. ; Measurements of influxes were carried out under continuous intracellular ; perfusion with an isotonic solution of potassium sulfate. The Na²⁴ ; permeability of the resting (excitable) axonal membrane

ICHIJI TASAKI

1963-01-01

286

The Winnowing: Establishing the Squid-Vibrio Symbiosis  

NSDL National Science Digital Library

This Nature Reviews Microbiology article examines the symbiosis between the squid Euprymna scolopes and its luminous bacterial symbiont, Vibrio fischeri. Using image-rich illustrations, it depicts the progression of light-organ colonization as a series of steps and discusses the advent of genomic approaches used to study this model system. A subscription is required to access the full-text version of this article.

Nyholm, Spencer V.; Mcfall-Ngai, Margaret; Microbiology, Nature R.

287

Squid's Built-In Light to Inspire New Gadgets?  

NSDL National Science Digital Library

This National Geographic news article describes a type of nocturnal squid found in the ocean around Hawaii which mates using a built-in flashlight to hide its shadow from predatory fish on the seafloor. Its unique light organ - composed of stacks of silvery reflector plates that surround colonies of luminescent, symbiotic bacteria - may inspire a new generation of high-tech miniature gadgets. This 2-page article includes links to related articles and additional National Geographic resources.

Roach, John

2009-06-26

288

Practical dc SQUIDs with extremely low 1\\/f noise  

Microsoft Academic Search

A large number of highly robust and reliable thin-film dc SQUIDs have been designed and fabricated which have excellent low-frequency noise properties. Measurements performed on isolated devices have yielded a limit on the low-frequency (1\\/f) flux noise component which is at least a factor of 60 below the average value reported for devices of this kind. The corresponding energy factor

C. D. Tesche; K. H. Brown; A. C. Callegari; M. M. Chen; J. H. Greiner; H. C. Jones; M. B. Ketchen; K. K. Kim; A. W. Kleinsasser; H. A. Notarys

1985-01-01

289

Interactive Fly: Maternally transcribed genes  

NSDL National Science Digital Library

The maternally transcribed genes section of the award-winning and comprehensive site: Interactive fly. It thoroughly discusses genes, tissues, biochemical paths, and developmental processes in the fruit fly, Drosophila.

PhD Thomas B Brody (NIH Laboratory of Neurochemistry)

2006-11-13

290

Numerical studies on dc-SQUID sensors with tightly coupled input coil  

NASA Astrophysics Data System (ADS)

We investigated the behavior of two low-Tc direct current superconducting quantum interference device (dc-SQUID) sensors with integrated input coil. A model including the capacitance of the Josephson junctions, thermal noise of the integrated shunt- and damping-resistors as well as a frequency dependent inductance of the SQUID loop was determined and numerically simulated. The SQUID inductance is found to be mainly influenced by parasitic elements introduced by the integrated coils. The simulated characteristics of the examined SQUIDs show many features also seen in experiments, including a hysteresis due to the frequency dependent washer impedance. The measured sensitivity of one of the designs fits well to the simulated value.

Pleikies, J.; Usenko, O.; Flokstra, J.

2008-02-01

291

Statistical characterization of voltage-biased SQUIDs with weakly damped junctions  

NASA Astrophysics Data System (ADS)

Recently, it has been shown that voltage-biased readout of SQUIDs with weakly damped junctions (large Stewart-McCumber parameter ?c, due to high shunt resistance) is useful for suppression of preamplifier noise. We experimentally studied the characteristics of 53 planar niobium-SQUID magnetometers with junction shunt resistors RJ nominally of 30 ? fabricated on 5 × 5 mm2 chips. The field-to-flux transfer coefficient ?B/?? of the magnetometers was 1.5 nT/?0, with a SQUID loop inductance Ls of about 350 pH. The distributions of important SQUID parameters, such as the current swing Iswing, the dynamic resistance Rd, and the flux-to-voltage transfer coefficient ?V/??, are given. Nearly all the SQUIDs could be stably operated in the voltage bias mode and their ?V/?? reached a large mean value of 380 ?V/?0. In this case, the SQUIDs can be read out directly by a commercial operational amplifier without any additional means to suppress preamplifier noise. The mean flux noise of the SQUIDs was found to be 4.5 ??0 Hz-1/2, corresponding to a field resolution of 7 fT Hz-1/2. To demonstrate the applicability of these SQUIDs in the direct readout scheme, a simple four-channel SQUID gradiometer system was set up to perform magnetocardiography and magnetoencephalography measurements in a magnetically shielded room.

Liu, Chao; Zhang, Yi; Mück, Michael; Zhang, Shulin; Krause, Hans-Joachim; Braginski, Alex I.; Zhang, Guofeng; Wang, Yongliang; Kong, Xiangyan; Xie, Xiaoming; Offenhäusser, Andreas; Jiang, Mianheng

2013-06-01

292

High Tc SQUID Detector for Magnetic Metallic Particles in Products  

NASA Astrophysics Data System (ADS)

High-Tc superconducting quantum interference device (SQUID) is an ultra-sensitive magnetic sensor. After the discovery of the high-Tc superconducting materials, the performance of the high-Tc SQUID has been improved and stabilized. One strong candidate for application is a detection system of magnetic foreign matters in industrial products. There is a possibility that ultra-small metallic foreign matter has been accidentally mixed with industrial products such as lithium ion batteries. If this happens, the manufacturer of the product suffers a great loss recalling products. The outer dimension of metallic particles less than 100 micron cannot be detected using X-ray imaging, which is commonly used for the inspection. Therefore a highly sensitive system for small foreign matters is required. We developed detection systems based on high-Tc SQUID for industrial products. We could successfully detect small iron particles of less than 50 micron on a belt conveyer. These detection levels were hard to be achieved using conventional X-ray detection or other methods.

Tanaka, Saburo; Akai, Tomonori; Hatsukade, Yoshimi; Suzuki, Shuichi

293

SQUID sensor application for small metallic particle detection  

NASA Astrophysics Data System (ADS)

High-Tc superconducting quantum interference device (SQUID) is an ultra-sensitive magnetic sensor. Since the performance of the SQUID is improved and stabilized, now it is ready for application. One strong candidate for application is a detection system of magnetic foreign matters in industrial products or beverages. There is a possibility that ultra-small metallic foreign matter has been accidentally mixed with industrial products such as lithium ion batteries. If this happens, the manufacturer of the product suffers a great loss recalling products. The outer dimension of metallic particles less than 100 ?m cannot be detected by an X-ray imaging, which is commonly used for the inspection. Ionization of the material is also a big issue for beverages in the case of the X-ray imaging. Therefore a highly sensitive and safety detection system for small foreign matters is required. We developed detection systems based on high-Tc SQUID with a high-performance magnetic shield. We could successfully measure small iron particles of 100 ?m on a belt conveyer and stainless steel balls of 300 ?m in water. These detection levels were hard to be achieved by a conventional X-ray detection or other methods.

Tanaka, Saburo; Hatsukade, Yoshimi; Ohtani, Takeyoshi; Suzuki, Shuichi

2009-04-01

294

A micro SQUID using ultra-small tunnel junctions  

NASA Astrophysics Data System (ADS)

Basic characteristics of micro-SQUIDs (superconducting quantum interference devices) with very small tunnel junctions are presented. Through electron-beam lithography, angled deposition and lift-off, we have made aluminum SQUIDs, the loop size of which was from 2?m to 20?m. The Al-AlOx-Al tunnel junctions were 0.15 ?m× 0.15 ?m in size and the parallel resistance was of the order of 10 k? Transport measurement at low temperatures down to 30 mK reveals the following features of the device: (1) It does not show dissipationless supercurrent, i.e. the zero-bias resistance remains finite even at the lowest temperature. (2) The resistance varies periodically as a function of the magnetic fields. When the field is perpendicular to the SQUID loop plane, the period corresponds to one flux quantum through the loop. (3) In almost-parallel magnetic fields, the resistance oscillations continue up to about 0.9T, though the amplitude diminishes with the magnetic field. Thus, the device is applicable for the magnetic sensing in moderate magnetic fields. Noteworthy feature is that the power dissipation necessary for operation is extremely small, i.e., of the order of 1 fW.

Ootuka, Youiti; Yamagishi, Toru; Suzuki, Kazuya; Miyagawa, Yoshiko; Maekawa, Tadashi; Kanda, Akibobu

2009-02-01

295

Fabrication and characterization of shunted μ-SQUID  

NASA Astrophysics Data System (ADS)

In order to eliminate hysteresis, we have fabricated and characterized niobium based shunted micron size superconducting quantum interference devices (?-SQUIDs). We find a wide temperature range where these ?-SQUIDs are non-hysteretic in nature and show a very good Ic vs. B oscillations in hysteretic regime and V vs. B oscillations in non-hysteretic regime. Here we report the characteristics of a shunted- ?-SQUID (Wf38LS72D5). In this device we have achieved a large voltage modulation, in non-hysteretic regime, at various temperatures including such as 1.1 mV at 6.62 K with a transfer function V? = 7.2mV/?0. The figures within the original article PDF file, as supplied to AIP Publishing, were affected by a PDF-processing error. Consequently, the article re-flowed and pagination increased from 3 to 4 pages. This article was updated on 14 May 2014 to correct the PDF-processing error, with the scientific content remaining unchanged. Readers are advised that the replacement article PDF file contains an additional blank page to preserve the original pagination.

Kumar, Nikhil; Fournier, T.; Courtois, H.; Gupta, Anjan K.

2014-04-01

296

Low-frequency nuclear quadrupole resonance with a dc SQUID  

SciTech Connect

Conventional pure nuclear quadrupole resonance (NQR) is a technique well suited for the study of very large quadrupolar interactions. Numerous nuclear magnetic resonance (NMR) techniques have been developed for the study of smaller quadrupolar interactions. However, there are many nuclei which have quadrupolar interactions of intermediate strength. Quadrupolar interactions in this region have traditionally been difficult or unfeasible to detect. This work describes the development and application of a SQUID NQR technique which is capable of measuring intermediate strength quadrupolar interactions, in the range of a few hundred kilohertz to several megahertz. In this technique, a dc SQUID (Superconducting QUantum Interference Device) is used to monitor the longitudinal sample magnetization, as opposed to the transverse magnetization, as a rf field is swept in frequency. This allows the detection of low-frequency nuclear quadrupole resonances over a very wide frequency range with high sensitivity. The theory of this NQR technique is discussed and a description of the dc SQUID system is given. In the following chapters, the spectrometer is discussed along with its application to the study of samples containing half-odd-integer spin quadrupolar nuclei, in particular boron-11 and aluminum-27. The feasibility of applying this NQR technique in the study of samples containing integer spin nuclei is discussed in the last chapter. 140 refs., 46 figs., 6 tabs.

Chang, J.W.

1991-07-01

297

Fly a Leaf  

NSDL National Science Digital Library

In this outdoor, windy day activity, learners "fly" and race leaves along a line to discover which types of leaves catch the most wind. Which leaves are the best fliers? Why? Learners think about wind as an important environmental and physical factor, and how plants must adapt to its influence. What a fun way to take advantage of a windy day!

Science, Lawrence H.

1982-01-01

298

Go Fly a Kite  

ERIC Educational Resources Information Center

This article describes an "art kite" activity. The idea is to construct and decorate a non-flying kite that they could display for an art exhibit. Through the activity, students learn to give and take suggestions from one another, improve the quality of their work and set a wonderful atmosphere of collaboration. (Contains 1 online resource.)

Klopack, Ken

2009-01-01

299

Toward indoor flying robots  

Microsoft Academic Search

Developing a research autonomous plane for flying in a laboratory space is a challenge that forces one to understand the specific aerodynamic, power and construction constraints. In order to obtain a very slow flight while maintaining a high maneuverability, ultralight structures and adequate components are required. In this paper we analyze the wing, propeller and motor characteristics and propose a

Jean-D. Nicoud; J.-C. Zufferey

2002-01-01

300

Flying the Desk  

Microsoft Academic Search

The terminology ``flying the desk'' has had a bad connotation for aviators over the years, inferring that a pilot has been relegated from the aircraft cockpit to an earthbound office. A unique advanced transport flight station design, described in this paper, could change that implication. The Lockheed-Georgia Company, in a joint project with NASA, has designed, developed, and fabricated a

George A. Sexton

1986-01-01

301

Flying Boat Construction  

NASA Technical Reports Server (NTRS)

Technicians are pictured installing flaps and wiring on a flying-boat model, circa 1944 (page 47). Photograph published in Winds of Change, 75th Anniversary NASA publication, by James Schultz. Photograph also published in Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917-1958 by James R. Hansen (page 209).

1946-01-01

302

Cockroaches, House flies  

NSDL National Science Digital Library

Chapters 5-10 of a World Health Organization PDF on medical pests of importance in PDF format. Chatpers 5,6 cover Cockroaches and House flies respectively, remaining chapters go on to discuss guinea worm, fresh water snails, and proper pesticide application. These are extremely thorough control strategy texts with a great deal of information.

0002-11-30

303

Fruit Fly Trap!  

NSDL National Science Digital Library

In this activity, compare the effectiveness of different traps to catch fruit flies. Is apple cider vinegar or white vinegar better at trapping these little insects? Use this activity to practice the scientific method or as a science fair project. This activity guide includes a step-by-step instructional video.

Center, Saint L.

2013-01-17

304

Flying High with Spring.  

ERIC Educational Resources Information Center

Presents an art activity for first grade that uses multicolor scratch paper. Explains that students make scratch-drawings of bird nests, then, as a class, discuss types of birds and bird positions (such as sitting or flying), and finally each creates a bird to add to the nest. (CMK)

Harrington, Carolyn Lang

2000-01-01

305

FireFly `Spinthariscope'  

Microsoft Academic Search

IT must be well known that the lantern of a firefly, teased by being held with the fingers, emits irregular flashes from minute point-sources in the lantern which follow the normal flash, the light of which fills the entire lantern. I am wondering, however, if the very astonishing spectacle presented by a fly which has been bitten by a spider

R. W. Wood

1939-01-01

306

Time delays for attosecond streaking in photoionization of neon  

NASA Astrophysics Data System (ADS)

We revisit the time-resolved photoemission in neon atoms as probed by attosecond streaking. We calculate streaking time shifts for the emission of 2p and 2s electrons and compare the relative delay as measured in a recent experiment by Schultze et al. [Science 328, 1658 (2010), 10.1126/science.1189401]. The B-spline R-matrix method is employed to calculate accurate Eisenbud-Wigner-Smith time delays from multielectron dipole transition matrix elements for photoionization. The additional laser field-induced time shifts in the exit channel are obtained from separate, time-dependent simulations of a full streaking process by solving the time-dependent Schrödinger equation on the single-active-electron level. The resulting accurate total relative streaking time shifts between 2s and 2p emission lie well below the experimental data. We identify the presence of unresolved shake-up satellites in the experiment as a potential source of error in the determination of streaking time shifts.

Feist, Johannes; Zatsarinny, Oleg; Nagele, Stefan; Pazourek, Renate; Burgdörfer, Joachim; Guan, Xiaoxu; Bartschat, Klaus; Schneider, Barry I.

2014-03-01

307

Single-particle kinetic energies in solid neon  

SciTech Connect

Inelastic-eV-neutron-scattering experiments have been performed on solid natural neon at five temperatures between 4.7 and 26.4 K and at pressures between equilibrium vapor pressure and 17.6 MPa. Measurements of atomic-recoil line broadening were made within the impulse approximation. Average single-particle kinetic energies {l angle}{ital E}{sub {ital k}}{r angle} have been obtained by assuming a Gaussian atomic momentum distribution. A ground-state kinetic-energy value of 49.1{plus minus}2.8 K is found and the temperature variation of {l angle}{ital E}{sub {ital k}}{r angle} is determined. Comparisons are made to somewhat restricted deductions of {l angle}{ital E}{sub {ital k}}{r angle} from previous experiments on neutron-phonon scattering and heat capacity. Comparisons with existing theoretical calculations show that none of them predicts the observed ground-state kinetic energy, although cell-model variational calculations and self-consistent harmonic calculations in the literature find that the ground-state kinetic energy is substantially larger than the ground-state potential energy, in agreement with our results.

Peek, D.A.; Fujita, I.; Schmidt, M.C.; Simmons, R.O. (Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States))

1992-05-01

308

Multilayer Adsorption of Neon, Hydrogens, and Carbon Monoxide on Graphite.  

NASA Astrophysics Data System (ADS)

Multilayer adsorption of neon, hydrogens (H _2, HD, and D_2), and carbon monoxide on graphite have been investigated using ellipsometric-coverage vapor-pressure isotherm measurements. Chemical potentials at layer condensations and widths of the layer condensation steps were tabulated, and layer critical points were determined from the temperature dependence of the widths for all five adsorbates. In Ne we do not find evidence for reentrant first -order layering, which was previously found in Ar, Kr, and Xe. The adsorption behavior on graphite of H_2, HD, and D_2 is very similar. We observed temperature-dependent splitting and hysteresis in the fourth, fifth, and sixth layers in all three adsorbates. This may suggest structure changes, possibly between face-centered cubic and hexagonal closed-packed stacking, in these layers. In CO, below the bulk alpha- beta transition temperature, we have seen incomplete wetting with a series of layer-appearance transitions from the third to the tenth layer. Above the alpha-beta transition temperature, the thickness of the film remains around 11 layers. We observed reentrant first-order layering in the condensation of the fourth layer in CO. But the broadening feature is much weaker compared to Ar, Kr, and Xe, and is not observed at all in the higher layers.

Wu, Hong

309

Metal atom (Zn, Cd and Mg) luminescence in solid neon  

NASA Astrophysics Data System (ADS)

Luminescence spectroscopy of the metal atoms Mg, Zn and Cd isolated in solid neon is recorded using pulsed synchrotron radiation excitation of the ns1np1 1P1-ns2 1S0 resonance (n = 3, 4 and 5 respectively) transitions. Two features, a dominant band and a red-shoulder, are identified in the UV absorption spectra of Zn/Ne and Cd/Ne. Excitation of these features yields distinct emission bands with the red-shoulder absorption producing the smaller, Stokes-shifted emission. Nanosecond decaytime measurements, made with the time correlated single photon counting technique indicate the emission bands arise from the spin singlet 1P1-->1S0 transition. Hence, it is concluded that the duplication of absorption and emission features in the Cd/Ne and Zn/Ne systems arises from metal atom occupancy in two distinct sites. In contrast, Mg/Ne luminescence consists of single excitation and emission bands, indicative of occupancy in just one site. The occurrence of distinct photophysical characteristics of the linewidths, Stokes shift and lifetimes in the Mg/Ne system, compared with those recorded for Zn/Ne and Cd/Ne, is rationalized in terms of a different site occupancy for atomic Mg. Accurate interaction potentials for the ground states of the M . Ne diatomics are used to analyse site occupancies and interpret this contrasting behavior.

Healy, Brendan; Kerins, Paul; McCaffrey, John G.

2012-08-01

310

Interstellar oxygen, nitrogen and neon in the heliosphere  

NASA Technical Reports Server (NTRS)

Oxygen, nitrogen and neon pick-up ions of interstellar origin were detected for the first time with the Solar Wind Ion Spectrometer (SWICS) on board Ulysses. The interstellar origin of these ions is established by the following criteria: (a) they are singly charged, (b) they have the broad velocity distributions characteristic of pick-up ions, with an upper limit of twice the solar wind speed, (c) their relative abundance as a function of distance from the sun corresponds to the theoretical expectation, and (d) there is no relation to a planetary or cometary source. The interstellar abundance ratios He(+)/O(+), N(+)/O(+), Ne(+)/O(+) were investigated. At approximately 5.25 AU in the outermost part of Ulysses' trajectory He(+)/O(+) = 175(sup +70 sub -50) N(+)/O(+) = 0.13(sup +0.05 sub -0.05) and Ne(+)/O(+) = 0.18(sup +0.10 sub -0.07) were determined. For the interstellar gas passing through the termination region and entering the heliosphere (He/O)(sub 0) = 290(sup +190 sub -100), (N/O)(sub 0) = 0.13(sup +0.06 sub -0.06) and (Ne/O)(sub 0) = 0.20(sup +0.12 sub -0.09) were obtained from the pick-up ion measurements. Upper limits for the relative abundances of C(+) and C were also determined.

Geiss, J.; Gloeckler, G.; Mall, U.; Von Steiger, R.; Galvin, A. B.; Ogilvie, K. W.

1994-01-01

311

Helium and neon in lunar ilmenites of different antiquities  

NASA Technical Reports Server (NTRS)

Helium and neon were extracted from individual lunar ilmenite grains, approximately 100 micrometers in diameter, using a pulsed step-heating technique. Grains from lunar samples 71501 and 79035, believed to have been exposed to solar corpuscular radiation at greatly different times, were studied. The results found were consistent with the hypothesis that in addition to solar-wind-implanted gas, a second more deeply implanted component was present in both species of grains. Average isotopic ratios were determined giving equal weight to each of the particles. As found in depth studies employing chemical etching, both the He-3/He-4 and Ne-20/Ne-22 ratios were lower in the more deeply implanted gas than in the solar wind component. The He-3/He-4 ratio in the solar wind component of the more ancient grains was lower than that in the more recently exposed ones, whereas no difference was found for the more deeply embedded He. In the deeply embedded component of the ancient grains, the He-4/Ne-20 ratio was approx. 2x that found in the more recently exposed grains. In the shallowly implanted component, the ratio varied greatly from grain to grain, preventing comparison with the solar wind elemental composition.

Nier, A. O.; Schlutter, D. J.

1994-01-01

312

Isotopes of cosmic ray elements from neon to nickel  

NASA Technical Reports Server (NTRS)

Results obtained from a balloon exposure of a cosmic ray detector flown in 1977 are reported. The charge resolution ranged from 0.19 to 0.21 charge units between neon and nickel and the mass resolution for nuclei stopped in the emulsions ranged from 0.40 to 0.70 amu for A between 20 and 60 amu. This was enough to correctly identify almost all nuclei, but not to uniquely resolve neighboring mass peaks. Both Ne and Mg show evidence for neutron enrichment relative to the solar system abundance. Si and S are consistent with solar abundances, while Ar has no significant source abundances. P, Cl and K have essentially no primary component and the isotopic distribution observed is quite consistent with that expected from propagation. An excess of Ca-44 at the source is shown, indicating high metallicity in the source. The abundance of Fe-58 is nine percent or less, and Ni shows a one-to-one ratio for Ni-58 to 60, implying intermediate metallicity.

Waddington, C. J.; Freier, P. S.; Fickle, R. K.; Brewster, N. R.

1981-01-01

313

Strange particle production in neutrino-neon charged current interactions  

SciTech Connect

Neutral strange particle production in charged-current muon-neutrino interactions have been studied in the Fermilab 15-foot neon bubble chamber. Associated production is expected to be the major source of strange particles in charged-current neutrino interactions. sigma-neutral and xi-minus production by neutrinos was observed. The dependence on various leptonic and hadronic variables is investigated. A fit to single and associated production of s, s/anti-s, and c quarks is described based on the number of single and double strange particle production events. Inclusive neutral strange particle decays (V/sup 0/) production rates as a fraction of all charged-current events are measured and are tabulated. The lambda/K ratio is found to be 0.39 +- 0.04 and the fraction of lambda coming from sigma-neutral is (16 +- 5)%. The single- and double V/sup 0/ production was used to determine the associated s anti-s production rate and single s-quark production rate. 13 refs., 7 figs., 3 tabs. (LEW)

Plano, R.; Baker, N.J.; Connolly, P.L.; Kahn, S.A.; Murtagh, M.J.; Palmer, R.B.; Samios, N.P.; Tanaka, M.; Baltay, C.; Bregman, M.

1986-01-01

314

Quantum scattering of neon from a nanotextured surface.  

PubMed

Phonon exchange is the usual cause of decoherence in atom-surface scattering. By including quantum effects in the treatment of Debye-Waller scattering, we show that phonon exchange becomes ineffective when the relevant phonon frequencies are high. The result explains the surprising observation of strong elastic scattering of Ne from a Cu(100) surface nanotextured with a c(2 × 2) Li adsorbate structure. We extend a previous model to describe the phonon spectra by an Einstein oscillator component with an admixture of a Debye spectrum. The Einstein oscillator represents the dominant, high frequency vibration of the adsorbate, normal to the surface, while the Debye spectrum represents the substrate contribution. Neon scattering is so slow that exciting the adsorbate mode has a low probability and is impossible if the incident energy is below the threshold. Thus, adsorbate vibrations are averaged out. A theoretical discussion and calculation shows that under such circumstances the vibrations of a light adsorbate do not contribute to the Debye-Waller effect, with the result that Ne scattering at thermal energies is quantum mechanical and largely elastic, explaining the high reflectivity and the diffraction peaks observed experimentally. PMID:21715773

Levi, A C; Huang, C; Allison, W; Maclaren, D A

2009-06-01

315

The isotopes of neon in the galactic cosmic rays  

NASA Technical Reports Server (NTRS)

The paper examines the results obtained by the University of Chicago instrument on board the IMP 7 satellite used to measure the abundances of Ne-20 and Ne-22 in the galactic cosmic rays during 1973-1977, over the general energy range of 60-230 MeV per nucleon. It is reported that the instrument shows a mass resolution of 0.7 amu(sigma) which was confirmed by calibrating a backup instrument at the LBL Bevalac with separated beams of neon isotopes. Through the use of standard solar modulation and cosmic-ray propagation models, the cosmic-ray source ratio inferred is Ne-22/Ne-20 = 0.38 = or -0.07 which is significantly greater than the present solar system ratio. It is concluded that propagation effects or cross-section uncertainties cannot account for such a large abundance of Ne-22, and thus this measurement provides evidence that the cosmic rays come from a source region where the Ne-22 abundance is substantially greater than in solar system material.

Garcia-Munoz, M.; Simpson, J. A.; Wefel, J. P.

1979-01-01

316

Neon turbo-Brayton cycle refrigerator for HTS power machines  

NASA Astrophysics Data System (ADS)

We developed a prototype turbo-Brayton refrigerator whose working fluid is neon gas. The refrigerator is designed for a HTS (High Temperature Superconducting) power transformer and its cooling power is more than 2 kW at 65 K. The refrigerator has a turboexpander and a turbo-compressor, which utilize magnetic bearings. These rotational machines have no rubbing parts and no oil-components. Those make a long maintenance interval of the refrigerator. The refrigerator is very compact because our newly developed turbo-compressor is volumetrically smaller than a displacement type compressor in same operating specification. Another feature of the refrigerator is a wide range operation capability for various heat-loads. Cooling power is controlled by the input-power of the turbo-compressor instead of the conventional method of using an electric heater. The rotational speed of the compressor motor is adjusted by an inverter. This system is expected to be more efficient. We show design details, specification and cooling test results of the new refrigerator in this paper.

Hirai, Hirokazu; Hirokawa, M.; Yoshida, Shigeru; Nara, N.; Ozaki, S.; Hayashi, H.; Okamoto, H.; Shiohara, Y.

2012-06-01

317

Electron-impact excitation of neon at intermediate energies  

NASA Astrophysics Data System (ADS)

Large-scale R matrix with pseudostates calculations for electron collisions with neon atoms, using a recently developed parallel version of our B-spline R-matrix code, are reported. The calculations were carried out in the jK-coupling scheme. They are intended to provide converged (with respect to the number of coupled states) results for electron impact excitation of individual target states with dominant configurations 2p53s, 2p53p, and 2p53d for incident electron energies from threshold to 300 eV. The close-coupling expansion includes 457 target states, with the lowest 87 states representing the bound spectrum and the remaining 370 the ionization continuum. The results reveal dramatic reductions of the predicted excitation cross sections at intermediate energies due to a strong influence of coupling to the target continuum and the higher-lying Rydberg states. Comparison with available experimental data for the excitation of the 2p53s and 2p53p states raises questions about the absolute normalization in the measurements. Considerable improvement over previous work is obtained in the agreement between experiment and theory for the angle-differential cross sections. In particular, a long-standing discrepancy regarding the angular dependence for excitation of the metastable 2p53s levels is resolved.

Zatsarinny, Oleg; Bartschat, Klaus

2012-08-01

318

The thermal conductivity of neon, methane and tetrafluoromethane  

NASA Astrophysics Data System (ADS)

New, absolute measurements of the thermal conductivity of neon (Ne), methane (CH 4) and tetrafluoromethane (CF 4) are reported for the temperature range 308 to 428 K at pressures up to 10 MPa. The data have an estimated accuracy of ±0.3%. A statistical analysis of the density dependence of the thermal conductivity has been employed to deduce the thermal conductivity of the gases in the limit of zero density and the firt density coefficient. For methane the first density coefficient is well represented by a correlation based on data for monatomic gases whereas for tetrafluoromethane the same correlation greatly underestimates the same coefficient. The thermal conductivity in the limit of zero density has been used in conjuction with other transport property data to deduce a consistent set of effective cross-sections for the two gases over all the range of temperature studied, based entirely on experiment. Among other quantities the collision number for rotational relaxation has been deduced and is shown to be significantly different between the two gases. Although the Mason-Monchick approximation is inappropriate for the evaluation of some of the effective cross-sections for the gases, a recent, very simple formulation of the kinetic theory of polyatomic gases provides a satisfactory description of the thermal conductivity data.

Millat, J.; Ross, M.; Wakeham, W. A.; Zalaf, M.

1988-02-01

319

Diagnostics of APG discharge in neon with a small admixture of hydrogen  

NASA Astrophysics Data System (ADS)

The aim of this work is to study the atmospheric pressure glow discharge (APG discharge) in neon. The discharge was generated between two metal electrodes, which were covered with an alumina layer. A small admixture of hydrogen could be added to neon. The type of the discharge (as concerning filamentary or glow discharge) was mainly derived from electrical measurements. The light emitted by the discharge was studied by means of optical emission spectroscopy (OES) with a temporal and spatial resolution. The results confirm that in neon the same type of diffuse dielectric-barrier discharge can be generated as in helium, namely a transient sub-normal glow discharge. This regime was also observed if up to 1% of hydrogen was added to neon. In general the recorded spectra consisted of atomic spectral lines of neon, as well as hydrogen atomic lines and molecular bands of N2 and OH due to external admixture or impurities in the carrier gas. When the amount of impurities was low enough, a continuous spectrum probably belonging to bremsstrahlung of electrons on neutral atoms was observed.

Navrátil, Z.; Trunec, D.; Brablec, A.; St'ahel, P.; Brandenburg, R.; Wagner, H.-E.

2004-03-01

320

SQUIDS: Interactive Deformation of Superquadrics for Model Matching in Virtual Environments  

Microsoft Academic Search

This paper presents work-in-progress on SQUIDS, a system for the interactive creation and deformation of superquadric shapes in virtual environments. SQUIDS is one component of a prototype system for semi-automatically creating realistic virtual environments, based on image data captured from real-world scenes.

James Sinnott; Toby Howard

2000-01-01

321

Removal of sodium channel inactivation in squid axon by the oxidant chloramine-T  

Microsoft Academic Search

We have investigated the effects of a mild oxidant, chloramine- T (CT), on the sodium and potassium currents of squid axons under voltage- clamp conditions . Sodium channel inactivation of squid giant axons can be completely removed by CT at neutral pH . Internal and external CT treatment are both effective . CT apparently removes inactivation in an irreversible, all-

GING KUO WANG; MALCOLM S. BRODWICK; DOUGLAS C. EATON

1985-01-01

322

A high-Tc flip-chip SQUID gradiometer for mobile underwater magnetic sensing  

Microsoft Academic Search

We report on the development of a magnetic gradient tensor sensor based on high- Tc SQUIDs for marine surveying applications. The proposed system uses six planar gradiometers incorporated into a hexagonal pyramid structure where the combined output will provide a measure of the gradient tensor. This report focuses on the development and characterization of long baseline high- Tc SQUID gradiometers

S. T. Keenan; J. A. Young; C. P. Foley; J. Du

2010-01-01

323

Electromagnetic nondestructive evaluation: moving HTS SQUIDs, inducing field nulling and dual frequency measurements  

Microsoft Academic Search

We have previously shown that simple, single layer HTS SQUIDs can be used effectively in electromagnetic nondestructive evaluation (NDE) using eddy current techniques in a magnetically unshielded environment. HTS SQUID systems for NDE applications are expected to be small and portable allowing non-stationary measurements to be carried out in the Earth's field above a stationary sample. Here we present application-oriented

C. Carr; D. Mc A. McKirdy; E. J. Romans; G. B. Donaldson; A. Cochran

1997-01-01

324

JUMBO SQUID ( DOSIDICUS GIGAS ) BIOMASS OFF CENTRAL CHILE: EFFECTS ON CHILEAN HAKE ( MERLUCCIUS GAY I)  

Microsoft Academic Search

Jumbo squid ( Dosidicus gigas ) off central Chile (32 ?00'S-41 ?30'S) was estimated using data collected from July to November during 2005 and 2006 on board the commercial bottom trawl fleet, where D. gigas is part of the bycatch. A geostatistical approach was ap - plied to estimate the jumbo squid biomass in Chilean hake ( Merluccius gay i)

RUBEN ALARCÓN-MUÑOZ; LUIS CUBILLOS; CLAUDIO GATICA

2008-01-01

325

A review of the biology of the jumbo squid Dosidicus gigas (Cephalopoda: Ommastrephidae)  

Microsoft Academic Search

The taxonomy, functional morphology, evolutionary biology and ecology of the jumbo squid, Dosidicus gigas, were reviewed using the data from many Soviet\\/Russian expeditions and all available literature. D. gigas is one of the largest and most abundant of the nektonic squid in the epipelagic zone of the world Ocean. It occurs in the eastern Pacific with its species range limited

Ch. M. Nigmatullin; K. N. Nesis; A. I. Arkhipkin

2001-01-01

326

Predatory strategies of squid (Illex illecebrosus) attacking small and large fish  

Microsoft Academic Search

Feeding strategies are different when adult Illex illecebrosus prey on large (trout) and small fish (mummichogs). Attacks on trout are characterized by (1) rotation as the squid changes from tail?first to head?first swimming; (2) an approach phase involving rapid acceleration towards the prey; (3) a tracking phase where the squid slowly follows the trout; (4) the capture phase. No tracking

Timothy P. Foyle; Ronald K. Odor

1988-01-01

327

The locomotory function of the fins in the squid Loligo pealei  

Microsoft Academic Search

Kinematic data of high spatial and temporal resolution, acquired from image sequences of adult long-finned squid, Loligo pealei, during steady swimming in a flume, were used to examine the role of fins and the coordination between fin and jet propulsion in squid locomotion. Fin shape and body outlines were digitized and used to calculate fin wave speed, amplitude, frequency, angle

Erik J. Anderson; M. Edwin Demont

2005-01-01

328

Multiplexed Readout of MMC Detector Arrays Using Non-hysteretic rf-SQUIDs  

NASA Astrophysics Data System (ADS)

Metallic magnetic calorimeters (MMCs) are widely used for various experiments in fields ranging from atomic and nuclear physics to X-ray spectroscopy, laboratory astrophysics or material science. Whereas in previous experiments single pixel detectors or small arrays have been used, for future applications large arrays are needed. Therefore, suitable multiplexing techniques for MMC arrays are currently under development. A promising approach for the readout of large arrays is the microwave SQUID multiplexer that employs non-hysteretic rf-SQUIDs to create a frequency shift of high resonators that is in accordance with the detector signal and that can be monitored by using standard microwave measurement techniques. In this paper we discuss the design of a recently developed and fabricated 64 pixel detector array with integrated microwave SQUID multiplexer that was produced to test the suitability of this readout technique. The characterization of dc-SQUIDs with virtually identical washer design compared to the rf-SQUIDs of the SQUID multiplexer revealed that the crucial SQUID parameters such as the critical current of the Josephson junctions or the washer inductance are close to the design values and anticipates a successful operation of the SQUID multiplexer.

Kempf, S.; Wegner, M.; Gastaldo, L.; Fleischmann, A.; Enss, C.

2014-08-01

329

Evaluation of joint interface of friction stir welding between dissimilar metals using HTS-SQUID gradiometer  

Microsoft Academic Search

In this study, we investigated conductive properties of joint interfaces of friction stir welding (FSW) between dissimilar metals, stainless steel SUS304 and aluminum A6063, using a SQUID nondestructive evaluation (NDE) system. With current injection method, the current maps above the FSW specimens jointed under various conditions were measured by a HTS-SQUID gradiometer. The conductivities of the joint interfaces, which were

Y. Mashiko; Y. Hatsukade; T. Yasui; H. Takenaka; Y. Todaka; M. Fukumoto; S. Tanaka

2010-01-01

330

Spatial and temporal variation in elemental signatures of statoliths from the Patagonian longfin squid ( Loligo gahi )  

Microsoft Academic Search

Abstract: We quantified elemental signatures in statoliths of 718 Patagonian longfin squid ( Loligo gahi) collected in the vicinity of the Falkland Islands (southwest Atlantic) and at sites on the Patagonian Shelf and coastal Peru. All squid were assigned to a spawning cohort by size, spawning condition, and back-calculated spawning date based on daily increments in statoliths. The remaining statolith

Alexander I. Arkhipkin; Steven E. Campana; Jennifer FitzGerald; Simon R. Thorrold

2004-01-01

331

Single-particle kinetic energies in liquid neon  

SciTech Connect

High-energy neutron-scattering experiments are reported on three samples of liquid natural neon. One was at 25.8 K at low pressure and two near 35 K were pressurized to densities differing by 9%. Measurements were made at wave-vector transfers {ital Q} in the range 200--280 nm{sup {minus}1}, within the impulse approximation, with accounting for spectrometer resolution and multiple-scattering effects. Single-particle kinetic energies, {l angle}{ital E}{sub {ital k}}{r angle}, were determined by assuming a Gaussian atomic momentum distribution. The value {l angle}{ital E}{sub {ital k}}{r angle}/{ital k}{sub {ital B}}=52.8{plus minus}3.7 K at 25.8 K is found to be somewhat larger than a deduction in the literature from experimental work at {ital Q} values below 100 nm{sup {minus}1}. The difference between current measurements and the previous deduction can be attributed to the failure of previous measurements to operate within the impulse approximation. Our two values of {l angle}{ital E}{sub {ital k}}{r angle} near 35 K differ by (4{plus minus}0.3)%, a small relative difference. A comparison of the present results for {l angle}{ital E}{sub {ital k}}{r angle} with calculated values dependent upon {ital S}({ital Q}) measurements (and inferred pair-correlation functions) shows only qualitative agreement, as does a comparison with a published Wigner-Kirkwood expansion of the density matrix, using a Lennard-Jones potential.

Peek, D.A.; Schmidt, M.C.; Fujita, I.; Simmons, R.O. (Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States))

1992-05-01

332

Nuclear Moments and Differences in Mean Square Charge Radii of Short-Lived Neon Isotopes by Collinear Laser Spectroscopy  

Microsoft Academic Search

The nuclear moments and charge radii of short-lived neon isotopes were measured by the use of collinear laser spectroscopy at the on-line mass separator ISOLDE at CERN. After a general introduction the semiclassical theory of atomic spectra is given and the relevant properties are calculated for neon. The atomic physics section is followed by a description of the experimental setup

R W Geithner; R Neugart

2002-01-01

333

Origami Flying Disk  

NSDL National Science Digital Library

In this three-part activity, learners use paper to explore Bernoulli's Principle â fast-moving air has lower pressure than non-moving air. First, learners observe what happens when they hold a paper strip between their lips and blow. Then, learners conduct another test to examine how airplane wings provide lift. Finally, learners make an origami flying disc using only paper, tape, and their newfound knowledge of Bernoulli's Principle.

Tymony, Cy

2011-01-01

334

Angle-resolved auger electron spectra induced by neon ion impact on aluminum  

NASA Astrophysics Data System (ADS)

Auger electron emission from aluminum bombarded with 1 to 5 keV neon ions was studied by angle-resolved electron spectroscopy. EN( E) spectra were acquired by a cylindrical mirror analyzer with a rotatable aperture in the entrance annulus. Auger signals from both neon and aluminum atoms were obtained. The position and shape of the spectral features depended on the incident ion energy, angle of ion incidence, and electron take-off angle with respect to the aluminum surface. These spectral dependencies were interpreted in terms of the Doppler shift given to the Auger electron velocity by the excited atom ejected into the vacuum. For oblique ion incidence it is concluded that a flux of high energy atoms are ejected in a direction close to the projection of the ion beam on the target surface. In addition, a new spectral feature was found and identified as due to Auger emission from excited neon in the aluminum matrix.

Pepper, Stephen V.; Aron, Paul R.

1986-04-01

335

Photochemistry of the ozone-water complex in cryogenic neon, argon, and krypton matrixes.  

PubMed

The photochemistry of ozone-water complexes and the wavelength dependence of the reactions were studied by matrix isolation FTIR spectrometry in neon, argon, and krypton matrixes. Hydrogen peroxide was formed upon the irradiation of UV light below 355 nm. Quantitative analyses of the reactant and product were performed to evaluate the matrix cage effect of the photoreaction. In argon and krypton matrixes, a bimolecular O((1)D) + H2O ? H2O2 reaction was found to occur to form hydrogen peroxide, where the O((1)D) atom generated by the photolysis of ozone diffused in the cryogenic solids to encounter water. In a neon matrix, hydrogen peroxide was generated through intracage photoreaction of the ozone-water complex, indicating that a neon matrix medium is most appropriate to study the photochemistry of the ozone-water complex. PMID:24252115

Tsuge, Masashi; Tsuji, Kazuhide; Kawai, Akio; Shibuya, Kazuhiko

2013-12-12

336

Nova LMC (Large Magellanic Cloud) 1990 No. 1: The first extragalactic neon Nova  

SciTech Connect

IUE observations of Nova LMC 1990 No. 1, the first neon (or ONeMg) nova observed outside the Galaxy, were obtained from 17 January 1990 through March 1990, with especially dense coverage during the first 25 days of the outburst. (The neon'' nova categorization is based on the detection of forbidden Ne III-V lines in optical spectra; the ultraviolet neon lines were not detected.) During the first 30 days of the outburst, the radiative losses were dominated by the N V {lambda}1240 and C IV {lambda}1550 lines. The maximum ejection velocity was approximately 8000 km/s, based on the blue absorption edge of the C IV P-Cygni profile. Early in the outburst of Nova LMC 1990 No. 1 the UV luminosity alone was {approximately} 3 {times} 10{sup 38} erg/sec, implying that the bolometric luminosity was well in excess of the Eddington luminosity for a one solar mass object. 9 refs., 4 figs.

Sonneborn, G. (National Aeronautics and Space Administration, Greenbelt, MD (USA). Goddard Space Flight Center Colorado Univ., Boulder, CO (USA). IUE Regional Data Analysis Facility); Shore, S.N. (Computer Sciences Corp., El Segundo, CA (USA) Colorado Univ., Boulder, CO (USA). IUE Regional Data Analysis Facility); Starrfield, S.G. (Arizona State Univ., Tempe, AZ (USA). Dept. of Physics and Astron

1990-01-01

337

Highly sensitive miniature SQUID magnetometer fabricated with cross-type Josephson tunnel junctions  

NASA Astrophysics Data System (ADS)

We report on a new method suitable for the fabrication of highly sensitive SQUID magnetometers exhibiting very small effective areas. In contrast to commonly used approaches, which mostly make use of constrictions in a superconducting material to form the Josephson junctions, we have been able to fabricate such sensors with SIS cross-type Josephson tunnel junctions in an Nb/AlOx/Nb trilayer process. The small junction size and vanishing idle region of our cross-type junctions and a therefore very low capacitance lead to a high sensitivity of the resulting SQUIDs. First results on fabricated miniature SQUID magnetometer within this technology are shown. We found, that even with SQUID loop dimensions of about 10 × 10 ?m2 very low flux noise levels could be achieved, which clearly demonstrate the high potential of our approach. Furthermore we estimate the required SQUID parameter which may allow the detection of single electron spin-flips with such devices in the future.

Schmelz, M.; Stolz, R.; Zakosarenko, V.; Anders, S.; Fritzsch, L.; Roth, H.; Meyer, H.-G.

2012-06-01

338

Technical and commerical challenges in high Tc SQUIDs and their industrial applications  

NASA Technical Reports Server (NTRS)

A SQUID is the most sensitive device for measuring changes in magnetic flux. Since its discovery in the sixties, scientists have made consistent efforts to apply SQUID's to various applications. Instruments that are the most sensitive in their respective categories have been built, such as SQUID DC susceptometer that is now manufactured by Quantum Design, pico-voltmeter which could measure 10(exp -14) volts, and gravitational wave detectors. One of the most successful applications of SQUID's is in magnetoencephalography, a non-invasive technique for investigating neuronal activity in the living human brain. This technique employs a multi-channel SQUID magnetometer that maps the weak magnetic field generated by small current when information is processed in brain, and its performance is marvelous.

Lu, D. F.

1995-01-01

339

Solar noble gases in the Earth: The systematics of helium-neon isotopes in mantle derived samples  

NASA Astrophysics Data System (ADS)

Primordial 3He, together with neon showing enrichment in 20Ne and 21Ne relative to 22Ne compared with atmospheric values, have been identified in many samples derived from the Earth's mantle. To explain the enrichment of 21Ne and 20Ne in the mantle source regions for these samples, it is necessary to mix at least two distinct non-atmospheric neon components. The two most likely candidates are nucleogenic and solar neon. Nucleogenic 21Ne, produced by local decay of U and Th, elevates {21Ne }/{22Ne } ratios. Solar neon is the only known component which has a {20Ne }/{22Ne } ratio greater than both the atmospheric value and the {20Ne }/{22Ne } ratios observed in terrestrial samples. We suggest, therefore, as a working hypothesis to account for the observed non-atmospheric neon, that there has been mixing of two neon components, solar and nucleogenic, in the mantle. If the Earth's primordial composition was solar, then we expect to see a correlation between the helium and neon isotope systematics. This is because primordial helium and neon would all be solar, and variations in the observed {3He }/{4He } and {21Ne }/{22Ne } ratios in the mantle would be due to the time integrated ingrowth of radiogenic 4He ( 4He ?) and nucleogenic 21Ne ( 21Ne ?), having a constant {4He ?}/{21Ne ?} production ratio. This relationship can be explicitly stated as: {21Ne ?}/{22Ne s}=}( {4He }/{3He }) Mantle - ( {4He }/{3He }) s} {21Ne ?}/{4He ?}( {3He }/{22Ne }) s, where subscript S denotes the solar composition. Using the above equation we can calculate hypothetical {3He }/{4He } ratios related to the neon isotopic compositions in the mantle sources. We are able to correlate the observed {3He }/{4He } ratios of all available samples having non-atmospheric neon isotopic ratios with the slopes of neon mixing lines between mantle and present-day atmospheric neon in {20Ne }/{22Ne }- {21Ne }/{22Ne } space. Thus, the helium and neon isotopic signatures in the mantle can be explained by mixing of a primordial solar component, different fractions of radiogenic and nucleogenic components produced by radioactive processes inside the Earth, and a present-day atmospheric component. The correlation between observed helium and neon isotopic ratios in samples derived from the mantle provides strong support for the notion that a significant primordial noble gas component in the Earth was of solar composition. This provides a critical boundary condition for models regarding how and when the Earth acquired its volatiles, and how its atmosphere evolved.

Honda, Masahiko; McDougall, Ian; Patterson, Desmond

1993-09-01

340

SQUID magnetometry from nanometer to centimeter length scales  

NASA Astrophysics Data System (ADS)

Information stored in magnetic fields plays an important role in everyday life. This information exists over a remarkably wide range of sizes, so that magnetometry at a variety of length scales can extract useful information. Examples at centimeter to millimeter length scales include measurement of spatial and temporal character of fields generated in the human brain and heart, and active manipulation of spins in the human body for non-invasive magnetic resonance imaging (MRI). At micron length scales, magnetometry can be used to measure magnetic objects such as flux qubits; at nanometer length scales it can be used to study individual magnetic domains, and even individual spins. The development of Superconducting QUantum Interference Device (SQUID) based magnetometer for two such applications, in vivo prepolarized, ultra-low field MRI of humans and dispersive readout of SQUIDs for micro- and nanoscale magnetometry, are the focus of this thesis. Conventional MRI has developed into a powerful clinical tool for imaging the human body. This technique is based on nuclear magnetic resonance of protons with the addition application of three-dimensional magnetic field gradients to encode spatial information. Most clinical MRI systems involve magnetic fields generated by superconducting magnets, and the current trend is to higher magnetic fields than the widely used 1.5-T systems. Nonetheless, there is ongoing interest in the development of less expensive imagers operating at lower fields. The prepolarized, SQUID detected ultra-low field MRI (ULF MRI) developed by the Clarke group allows imaging in very weak fields (typically 132 muT, corresponding to a resonant frequency of 5.6 kHz). At these low field strengths, there is enhanced contrast in the longitudinal relaxation time of various tissue types, enabling imaging of objects which are not visible to conventional MRI, for instance prostate cancer. We are currently investigating the contrast between normal and cancerous prostate tissue in ex vivo prostate specimens in collaboration with the UCSF Genitourinary Oncology/Prostate SPORE Tissue Core. In characterizing pairs of nominally normal and cancerous tissue, we measure a marked difference in the longitudinal relaxation times, with an average value of cancerous tissue 0.66 times shorter than normal prostate tissue. However, in vivo imaging is required to definitively demonstrate the feasibility of ULF MR imaging of prostate cancer. To that end, we have worked to improve the performance of the system to facilitate human imaging. This is accomplished by increasing the prepolarizing field amplitude, and minimizing magnetic noise in the SQUID detector. We have achieved polarizing fields as high as 150 mT and SQUID effective field noise below 1 fT Hz-1/2, enabling us to demonstrate proof-of-principle in vivo images of the human forearm with 2 x 2 x 10 mm3 resolution in 6 minutes. On a much smaller spatial scale, there is currently fundamental and technological interest in measuring and manipulating nanoscale magnets, particularly in the quantum coherent regime. The observation of the dynamics of such systems requires a magnetometer with not only exceptional sensitivity but also high gain, wide bandwidth and low backaction. We demonstrate a dispersive magnetometer consisting of a two-junction SQUID in parallel with an integrated, lumped-element capacitor. Input flux signals are encoded as a phase modulation of the microwave drive tone applied to the magnetometer, resulting in a single quadrature voltage signal. For strong drive power, the nonlinearity of the resonator results in quantum limited, phase sensitive parametric amplification of this signal. We have achieved a bandwidth of 20 MHz---approximately two orders of magnitude higher than dispersive devices of comparable sensitivity---with an effective flux noise of 0.29 muphi0 Hz-12 . This performance is in excellent agreement with our theoretical model.

Hatridge, Michael Jonathan

341

Production of nucleogenic neon in the Earth from natural radioactive decay  

NASA Astrophysics Data System (ADS)

Nucleogenic neon isotope production resulting from ? decay of naturally occurring U and Th was calculated for typical compositions of the mantle and crust using a simple non-Monte Carlo code for neutron transport. The (?,n), (?,p), and (n, ?) reactions, leading to the production of neon isotopes in the outgoing reaction channel, are taken into account in the calculations. In the first stage of calculation, neon production from (?,n) and (?,p)reactions on 17O, 18O, and 19F is considered, and the neutron energy spectrum from (?,n) reactions on the major elements is derived. This spectrum is further used for calculation of the neon isotope yield from the reactions 24Mg (n,?)21Ne, 25Mg(n,?)22Ne, and 23Na(n,?)20Ne. The calculated production of nucleogenic neon is dominated by (?,n) reactions with oxygen in the Earth's mantle and crust. The present calculations give 21Ne/4He production ratios that are approximately half those of the previous estimates by Rison [1980] and Kyser and Rison [1982]. The present study also has shown that the nucleogenic 21Ne production from the 24Mg(n,?) reaction is only about one-fifth the previous estimate. The contribution of nucleogenic 21Ne from the 24Mg(n,?) reaction is insignificant compared with nucleogenic 21Ne production from 18O(?,n). Our estimate of the nucleogenic 21Ne/radiogenic 4He production ratio both in the mantle and in the crust is 4.5×10-8. This production ratio is quite consistent with nucleogenic 21Ne/radiogenic 4He ratios actually observed in crustal fluid samples ((4.6±0.8) ×10-8). The error in calculation of the nucleogenic neon production, resulting from a random statistical variation of the entry neutron yields and cross sections, is estimated to be less than 5%.

Yatsevich, Igor; Honda, Masahiko

1997-05-01

342

Multiplexing of Hot-Electron Nanobolometers Using Microwave SQUIDs  

NASA Astrophysics Data System (ADS)

We have obtained the first data on the multiplexed operation of titanium hot-electron bolometers (HEB). Because of their low thermal conductance and small electron heat capacity nanobolometers are particularly interesting as sensors for far-infrared spectroscopy and mid- and near-IR calorimetry. However, the short time constant of these devices (~?s at 300-400 mK) makes time domain or audio-frequency domain multiplexing impractical. The Microwave SQUID (MSQUID) approach pursued in this work uses dc SQUIDs coupled to X-band microresonators which are, in turn, coupled to a transmission line. We used a 4-element array of Ti HEBs operated at 415 mK in a He3 dewar with an optical fiber access. The microwave signal exhibited 10-MHz wide resonances at individual MSQUD frequencies between 9 GHz and 10 GHz. The resonance depth is modulated by the current through the bolometer via a change of the SQUID flux state. The transmitted signal was amplified by a cryogenic amplifier and downconverted to baseband using an IQ mixer. A 1-dB per ?0/2 responsivity was sufficient for keeping the system noise at the level of ~2 pA/Hz1/2. This is more than an order of magnitude smaller than phonon noise in the HEB. The devices were able to detect single near-IR photons (1550 nm) with a time constant of 3.5 ?s. Follow-on work will scale the array to larger size and will address the microwave frequency signal generation and processing using a digital transceiver.

Karasik, Boris S.; Day, Peter K.; Kawamura, Jonathan H.; Bumble, Bruce; Leduc, Henry G.

2009-12-01

343

A scanning SQUID microscope for imaging high-frequency magnetic fields  

NASA Astrophysics Data System (ADS)

This thesis examines the design and operation of a large-bandwidth scanning SQUID microscope for spatially imaging high frequency magnetic fields. Towards this end, I present results on a cryo-cooled 4.2 K scanning SQUID microscope with a bandwidth of dc to 2 GHz and a sensitivity of about 52.4 nT per sample. By using a thin-film hysteretic Nb dc-SQUID and a pulsed sampling technique, rather than a non-hysteretic SQUID and a flux-locked loop, the bandwidth limitation of existing scanning SQUID microscopes is overcome. The microscope allows for non-contact images of time-varying magnetic field to be taken of room-temperature samples with time steps down to 50 ps and spatial resolution ultimately limited by the size of the SQUID to about 10 mum. The new readout scheme involves repeatedly pulsing the bias current to the dc SQUID while the voltage across the SQUID is monitored. Using a fixed pulse amplitude and applying a fixed dc magnetic flux allows the SQUID to measure the applied magnetic flux with a sampling time set by the pulse length of about 400 ps. To demonstrate the capabilities of the microscope, I imaged magnetic fields from 0 Hz (static fields) up to 4 GHz. Samples included a magnetic loop, microstrip transmission lines, and microstrip lines with a break in order to identify and isolate electrical opens in circuits. Finally, I discuss the operation and modeling of the SQUID and how to further increase the bandwidth of the microscope to allow bandwidth of upwards of 10 GHz.

Vlahacos, Constantine P.

344

Removal of Potassium Negative Resistance in Perfused Squid Giant Axons  

PubMed Central

Squid giant axons, internally and externally perfused with solutions having potassium as the only cation, exhibit an approximately linear steady-state current-voltage relation. When small amounts of calcium and magnesium are present in the external potassium solution, the current-voltage curve is markedly nonlinear, exhibiting the rectification and negative resistance which have been observed for intact axons in isosmotic potassium solutions. The effects of perfusion and removal of external divalent cations are interpreted in terms of two components of current, a linear component and a nonlinear time-varying component. The former is increased and the latter diminished by the removal of the external divalent cations.

Lecar, Harold; Ehrenstein, Gerald; Binstock, Leonard; Taylor, Robert E.

1967-01-01

345

Sensitive RF-SQUIDs and magnetometers operating at 77 K  

Microsoft Academic Search

Large 6-mm×6-mm and 8-mm×8-mm flux-focusing washer structures with inductances LS between 25 pH and 500 pH were fabricated from epitaxial, c-axis YBa2Cu3O7 films. Double step-edge junctions having a low 1\\/f noise were incorporated in these washers to form RF-SQUIDs (superconducting quantum interference devices). A high tank circuit frequency near 150 MHz was chosen to reduce noise and improve the sensitivity

Y. Zhang; M. Miick; K. Herrmann; W. Zander; A. i. Braginski; C. Heiden

1993-01-01

346

In a Tiny Squid, Bacterial Toxin Governs Organ Development  

NSDL National Science Digital Library

This EurekAlert! kids news article features information about the toxic molecule, tracheal cytotoxin, which is responsible for forming a light producing organ in the Bobtail squid-bacteria symbiosis. This toxin has been discovered to have both good and bad effects depending on the type of bacteria and host involved in the symbiosis: on one hand, it could cause disease and massive tissue damage, while on the other, it is vitally important in organ development. These recently discovered effects may force biologists to re-think the relationship between the world's many microorganisms and their host plants/animals.

EurekAlert!; American Association for the Advancement of Science (AAAS)

347

A 5MHz bandwidth SQUID magnetometer with additional positive feedback  

Microsoft Academic Search

A fast SQUID (superconducting quantum interference device) magnetometer system using the latest multiloop magnetometer W7A with additional positive feedback has been built. A 3-dB bandwidth of 5 MHz has been achieved in a simple direct-coupled flux-locked loop. The feedback range is ±620 &Fgr;0 or ±290 nT, the white-noise level 3.4×10?6 &Fgr;0\\/&sqrt;Hz or 1.6 fT\\/&sqrt;Hz, and the 1\\/ f corner frequency

D. Drung; H. Matz; H. Koch

1995-01-01

348

Sub-10 nm nanofabrication with the helium and neon ions in ORION NanoFab  

NASA Astrophysics Data System (ADS)

With the advancement of scientific research, nanofabrication is continually being pushed to its limits. For rapid prototyping and fast turnaround, gallium focused ion beam (FIB) based instruments are often used. These charged particle instruments offer great flexibility and high throughput for prototyping customized devices for research and development as well as industrial applications. A new entrant in the field of nanofabrication using charged particle beams is the ORION NanoFab made by Carl Zeiss. In ORION NanoFab, helium and neon ions can be used to produce features as small as few nanometers. In this article, we will describe the advantages and limitations of helium and neon ion based nanofabrication.

Singh, Bipin

2013-04-01

349

Spitzer finds cosmic neon's and sulfur's sweet spot: part III, NGC 6822  

NASA Astrophysics Data System (ADS)

We observed several H ii regions in the dwarf irregular galaxy NGC 6822 using the infrared spectrograph on the Spitzer Space Telescope. Our aim is twofold: first, to examine the neon to sulfur abundance ratio in order to determine how much it may vary and whether or not, it is fairly ‘universal’ second, to discriminate and test the predicted ionizing spectral energy distribution between various stellar atmosphere models by comparing with our derivation of the ratio of fractional ionizations involving neon and sulfur. This work extends our previous similar studies of H ii regions in M83 and M33 to lower metallicities.

Rubin, R. H.; McNabb, I. A.; Simpson, J. P.; Dufour, R. J.; Pauldrach, A. W. A.; Colgan, S. W. J.; Craven, T. W.; Gitterman, E. D.; Lo, C. C.

2010-03-01

350

Pest Control on the "Fly"  

NASA Technical Reports Server (NTRS)

FlyCracker(R), a non-toxic and environmentally safe pesticide, can be used to treat and control fly problems in closed environments such as milking sheds, cattle barns and hutches, equine stables, swine pens, poultry plants, food-packing plants, and even restaurants, as well as in some outdoor animal husbandry environments. The product can be applied safely in the presence of animals and humans, and was recently permitted for use on organic farms as livestock production aids. FlyCracker's carbohydrate technology kills fly larvae within 24 hours. By killing larvae before they reach the adult stages, FlyCracker eradicates another potential breeding population. Because the process is physical-not chemical-flies and other insects never develop resistance to the treatment, giving way to unlimited use of product, while still keeping the same powerful effect.

2002-01-01

351

Build a Fruit Fly Trap  

NSDL National Science Digital Library

In this construction activity, students use a 2-liter bottle to build a fly trap. There is not much supporting information besides the directions, but the trap can be used to examine fly behavior, and it might also be redesigned by students. In the construction part of the activity, younger learners will need help and supervision from an older learner or adult, but any age learner can do independent observation of fly behavior once insects are inside the trap.

Wisconsin-Madison, Universitiy O.

2007-01-01

352

[Medical supply of long flies].  

PubMed

The article presents a characteristics of main negative factors, disimproving a functional condition and working capacity of airmen in long flies: long stay in a working pose, necessity of using of summer form, of defense form and oxygen-breath means, peculiarities of eating in fly, solving of nature-imposed necessity, relative sensor deprivation, sameliness of environment, high level of noise, hypokinesia, high nervous-emotional tension in conditions of air refueling, temperature fall, difference of barometric pressure, desynchronisms. Were given practical recommendations on maintenance of functional and working capacity of members of flying staff, realizing long flies. PMID:20698321

Belevitin, A B; Tsygan, V N; Blagitin, A A; Lizogub, I N

2010-05-01

353

Neural control of tuneable skin iridescence in squid  

PubMed Central

Fast dynamic control of skin coloration is rare in the animal kingdom, whether it be pigmentary or structural. Iridescent structural coloration results when nanoscale structures disrupt incident light and selectively reflect specific colours. Unlike animals with fixed iridescent coloration (e.g. butterflies), squid iridophores (i.e. aggregations of iridescent cells in the skin) produce dynamically tuneable structural coloration, as exogenous application of acetylcholine (ACh) changes the colour and brightness output. Previous efforts to stimulate iridophores neurally or to identify the source of endogenous ACh were unsuccessful, leaving researchers to question the activation mechanism. We developed a novel neurophysiological preparation in the squid Doryteuthis pealeii and demonstrated that electrical stimulation of neurons in the skin shifts the spectral peak of the reflected light to shorter wavelengths (greater than 145 nm) and increases the peak reflectance (greater than 245%) of innervated iridophores. We show ACh is released within the iridophore layer and that extensive nerve branching is seen within the iridophore. The dynamic colour shift is significantly faster (17 s) than the peak reflectance increase (32 s), revealing two distinct mechanisms. Responses from a structurally altered preparation indicate that the reflectin protein condensation mechanism explains peak reflectance change, while an undiscovered mechanism causes the fast colour shift.

Wardill, T. J.; Gonzalez-Bellido, P. T.; Crook, R. J.; Hanlon, R. T.

2012-01-01

354

SQUID-Detected In Vivo MRI at Microtesla Magnetic Fields  

SciTech Connect

We use a low transition temperature (T{sub c}) Super-conducting Quantum Interference Device (SQUID) to perform in vivo magnetic resonance imaging (MRI) at magnetic fields around 100 microtesla, corresponding to proton Larmor frequencies of about 5 kHz. In such low fields, broadening of the nuclear magnetic resonance lines due to inhomogeneous magnetic fields and susceptibility variations of the sample are minimized, enabling us to obtain high quality images. To reduce environmental noise the signal is detected by a second-order gradiometer, coupled to the SQUID, and the experiment is surrounded by a 3-mm thick Al shield. To increase the signal-to-noise ratio (SNR), we prepolarize the samples in a field up to 100 mT. Three-dimensional images are acquired in less than 6 minutes with a standard spin-echo phase-encoding sequence. Using encoding gradients of {approx}100 {micro}T/m we obtain three-dimensional images of bell peppers with a resolution of 2 x 2 x 8 mm{sup 3}. Our system is ideally suited to acquiring images of small, peripheral parts of the human body such as hands and arms. In vivo images of an arm, acquired at 132 {micro}T, show 24-mm sections of the forearm with a resolution of 3 x 3 mm{sup 2} and a SNR of 10. We discuss possible applications of MRI at these low magnetic fields.

Moble, Michael; Myers, Whittier R; Lee, SeungKyun; Kelso, Nathan; Hatridge, Michael; Pines, Alexander; Clarke, John

2005-06-01

355

Integrated Directly-Coupled SQUID Magnetometer and Gradiometer  

NASA Astrophysics Data System (ADS)

In this work, we investigated the directly-coupled superconducting quantum interference device (SQUID) magnetometer and gradiometer with integrated pickup loops. To prepare the structures, we fabricated the YBa2Cu3O7-x thin films on strontium titanate (SrTiO3) substrates by magnetron rf sputtering. The devices were patterned by ultraviolet photolithography followed by a three-step wet etching process. The circular and differential modulation coils for the magnetometer and gradiometer, respectively, were wound on bakelite frames attached to the back of the chip mount. The voltage-current and voltage-flux characteristics of option SQUIDs on the chip, which was put in a switching-channel electrical cryostat, were characterized by using the low-noise preamplifier, the homemade currentwaveform generator, and the computer-based data acquisition unit. The magnetometer and the gradiometer can be operated simultaneously by independent flux-locked loops. The proposed sensor can be applied to the nondestructive evaluation and biomagnetic imaging, for example, magnetocardiogram.

Chang, Chan-Yao; Hsu, Chi-Ming; Jeng, Jen-Tzong

356

Hierarchical, self-similar structure in native squid pen.  

PubMed

The structure of native squid pen (gladius) was investigated in two different species on different length scales. By combining microscopy, atomic force microscopy (AFM), and X-ray diffraction, the experiments probed length scales from millimetres down to nanometres. The gladii showed a hierarchical, self-similar structure in the optical experiments with fibres of different size oriented along the long axis of the gladius. The fibre-like structure was reproduced at the nanoscale in AFM measurements and fibres with diameters of 500 ?m, 100 ?m, 10 ?m, 2 ?m and 0.2 ?m were observed. Their molecular structure was determined using X-ray diffraction. In the squid gladius, the chitin molecules are known to form nano-crystallites of monoclinic lattice symmetry wrapped in a protein layer, resulting in ?-chitin nano-fibrils. Signals corresponding to the ?-coil protein phase and ?-chitin crystallites were observed in the X-ray experiments and their orientation with respect to the fibre-axis was determined. The size of a nano-fibril was estimated from the X-ray experiments to be about 150 × 300 Å. About 100 of these nano-fibrils are needed to form a 0.2 ?m thick micro-fibre. We found that the molecular structure is highly anisotropic with ?90% of the ?-coils and ?-chitin crystallites oriented along the fibre-axis, indicating a strong correlation between the macroscale structure and molecular orientation. PMID:24957525

Yang, Fei-Chi; Peters, Robert D; Dies, Hannah; Rheinstädter, Maikel C

2014-07-01

357

Impact of SQUIDs on functional imaging in neuroscience  

NASA Astrophysics Data System (ADS)

This paper provides an overview on the basic principles and applications of magnetoencephalography (MEG), a technique that requires the use of many SQUIDs and thus represents one of the most important applications of superconducting electronics. Since the development of the first SQUID magnetometers, it was clear that these devices could be used to measure the ultra-low magnetic signals associated with the bioelectric activity of the neurons of the human brain. Forty years on from the first measurement of magnetic alpha rhythm by David Cohen, MEG has become a fundamental tool for the investigation of brain functions. The simple localization of cerebral sources activated by sensory stimulation performed in the early years has been successively expanded to the identification of the sequence of neuronal pool activations, thus decrypting information of the hierarchy underlying cerebral processing. This goal has been achieved thanks to the development of complex instrumentation, namely whole head MEG systems, allowing simultaneous measurement of magnetic fields all over the scalp with an exquisite time resolution. The latest trends in MEG, such as the study of brain networks, i.e. how the brain organizes itself in a coherent and stable way, are discussed. These sound applications together with the latest technological developments aimed at implementing systems able to record MEG signals and magnetic resonance imaging (MRI) of the head with the same set-up pave the way to high performance systems for brain functional investigation in the healthy and the sick population.

Della Penna, Stefania; Pizzella, Vittorio; Romani, Gian Luca

2014-04-01

358

Flux noise in SQUIDs: calculations of geometrical dependence  

NASA Astrophysics Data System (ADS)

Low frequency (1/f) magnetic flux noise in SQUIDs is understood to arise from the random reversal of electron spins localized at the surface of the superconducting film. Analytical results^1 that assume independent electron spins predict that the spectral density at 1 Hz scales with the washer geometry approximately as R/W in the limit R/W1. Here, R is the outer radius and W is the linewidth. We present numerical calculations that reproduce the analytical result in the appropriate limit and extend these results to arbitrary values of R/W. In addition, a logarithmic dependence on W, evident when R/W is fixed and W is varied, is reproduced and discussed. The contribution of spins at the edge of the film is also computed. We compare the predicted geometrical scaling to our recent measurements of several SQUIDs with varying geometries. Our calculation that is valid for all values of R/W enables us to investigate a possible breakdown of the independent spin model in our experimental data. ^1R. C. Bialczak et al., Phys. Rev. Lett. 99, 187006 (2007).

O'Kelley, Sean; Pepper, Keenan; Anton, Steven; Birenbaum, Jeffrey; Clarke, John

2012-02-01

359

[Otorhinolaryngologic diseases and flying].  

PubMed

Physiological and pathological aspects of pressure changes, noise, acceleration, variation of temperature, low humidity, stress and time differences in flight passengers and aircrew are discussed. Typical ear, nose, and throat clinic (ENT)-cases such as tubal function disturbances, barotrauma, hypacusis, sudden hearing loss, tinnitus, acute and chronic middle ear diseases, post ear surgery conditions, hearing aids, vertigo and motion sickness are described. The influence on flying of acute and chronic affections of the paranasal sinuses, nasal septal deviation and allergy are listed. The problem of transport of ENT-incapacitated passengers in commercial aircrafts and ambulance jets are dealt with. PMID:12385068

Moser, M

2002-01-01

360

NOVA: Spies that Fly  

NSDL National Science Digital Library

Spies that Fly is a NOVA episode that originally aired in January 2003. This page of the television broadcast's online companion provides a fascinating historical account of unmanned aerial vehicles (UAV's). It will probably come as a surprise that the earliest UAV listed on this site was flown over four decades before the first manned airplane took off. From their modest beginnings, UAV's have evolved into extremely high tech instruments; the six-inch Black Widow UAV is one of the most extraordinary items described online. The Web site also shows some of the records for UAV technology.

361

Robber Flies (Asilidae)  

NSDL National Science Digital Library

This Web site focuses on "one of the largest and most abundant families of present day insects" -- the Robber Flies. Maintained by Fritz Geller-Grimm of the Museum Wiesbaden in Germany and Cornell University graduate student Torsten Dikow, the site includes a variety of information on many aspects of these insects. The Asilidae section contains many resources that are most appropriate for an advanced or research audience, including identification keys, species and distribution databases, and literature references. The Dipterology and Entomology sections include plenty of more general information suitable for a variety of audiences.

2008-09-15

362

Flying wires at Fermilab  

SciTech Connect

Transverse beam profile measurement systems called ''Flying Wires'' have been installed and made operational in the Fermilab Main Ring and Tevatron accelerators. These devices are used routinely to measure the emittance of both protons and antiprotons throughout the fill process, and for emittance growth measurements during stores. In the Tevatron, the individual transverse profiles of six proton and six antiproton bunches are obtained simultaneously, with a single pass of the wire through the beam. Essential features of the hardware, software, and system operation are explained in the rest of the paper. 3 refs., 4 figs.

Gannon, J.; Crawford, C.; Finley, D.; Flora, R.; Groves, T.; MacPherson, M.

1989-03-01

363

Fly like a fly [micro-air vehicle  

Microsoft Academic Search

A team of scientists has built a fly-size flight simulator in an attempt to understand flight control from the perspective of the common housefly. Results so far have shown, and further tests are expected to confirm, that the fly uses a flight control paradigm that is completely different from that of a fighter jet. Whereas the F-35 Joint Strike Fighter

R. Zbikowski

2005-01-01

364

Development of an image processing system in splendid squid quality classification  

NASA Astrophysics Data System (ADS)

Agricultural products typically exhibit high variance in quality characteristics. To assure customer satisfaction and control manufacturing productivity, quality classification is necessary to screen off defective items and to grade the products. This article presents an application of image processing techniques on squid grading and defect discrimination. A preliminary study indicated that surface color was an efficient determinant to justify quality of splendid squids. In this study, a computer vision system (CVS) was developed to examine the characteristics of splendid squids. Using image processing techniques, squids could be classified into three different quality grades as in accordance with an industry standard. The developed system first sifted through squid images to reject ones with black marks. Qualified squids were graded on a proportion of white, pink, and red regions appearing on their bodies by using fuzzy logic. The system was evaluated on 100 images of squids at different quality levels. It was found that accuracy obtained by the proposed technique was 95% compared with sensory evaluation of an expert.

Masunee, Niyada; Chaiprapat, Supapan; Waiyagan, Kriangkrai

2013-07-01

365

An Operation Circuit of a Micro-SQUID Magnetometer below 1 K  

NASA Astrophysics Data System (ADS)

We have been developing a micro superconducting quantum interference device ( ?-SQUID) magnetometer for the study of quantum effects in ?m- or nm-sized magnetic materials. In the ?-SQUID magnetometer, the sample is placed on the SQUID loop directly and the flux is detected by the loop itself. The close proximity between the sample and the SQUID loop is of great advantage for highly sensitive detection of magnetization from the tiny magnetic materials. However, the heat release during the operation of the SQUID could cause a great problem in experiments below 1 K because of the close proximity of the SQUID and sample. Here we report a digital circuit for the ?-SQUID magnetometer which can reduce the heat release in the low temperature operation and whose parts are commercially available. The circuit consists of a FPGA-digital board with analog-to-digital and digital-to-analog converters, and an independent pre-amplifier. By using this circuit we succeeded in measuring quantum tunneling of magnetization in the single molecule magnet, Mn12Ph at 0.7 K.

Yamaguchi, A.; Wada, M.; Tani, R.; Takeda, K.; Matsumoto, T.; Kashiwaya, H.; Motoyama, G.; Kashiwaya, S.; Ohkoshi, S.; Sumiyama, A.

2011-03-01

366

Influence of squid liver powder on accumulation of cadmium in serum, kidney and liver of mice.  

PubMed

In this study, the effect of squid liver powder intake on accumulation of cadmium in mice was investigated. Subjects were divided into 4 groups including the control group (CON), squid liver powder group with lipids not removed (SLP100), and squid liver powder groups with lipids removed (LFSLP50 and LFSLP100). Feed intake and food efficiency ratio of squid liver powder groups was significantly higher than the CON. As a result of investigating cadmium content in hair, serum, liver, and kidney during intake of squid liver powder, all groups showed increase in cadmium accumulation through consistent, long-term intake. Especially, cadmium content in liver and kidney of LFSLP100 was significantly higher than the content of SLP100 and CON. As a result of pathological observation on liver and kidney tissues according to squid liver powder diet, LFSLP100 showed most serious pathological symptoms. In case of kidney tissues, degeneration was significantly more severe in LFSLP100 compared to other groups. Such results suggest that cadmium concentration in human body can be increased by ingestion of whole squid including internal organs and that tissues can be damaged by increased cadmium concentration. More specific and systematic studies are deemed necessary. PMID:24471103

Kim, Byoung-Mok; Lee, Soo-Young; Jeong, In-Hak

2013-03-01

367

A path integral Monte Carlo study of liquid neon and the quantum effective pair potential  

Microsoft Academic Search

The path integral Monte Carlo (PIMC) method is used to simulate liquid neon at T=40 K. It is shown that quantum effects are not negligible and that when the quantum effective pair potential is used in a classical molecular dynamics simulation the results obtained for the radial distribution function agrees with that predicted by a full path integral Monte Carlo

D. Thirumalai; Randall W. Hall; B. J. Berne

1984-01-01

368

Neural Dynamics of Form Perception: Boundary Completion, Illusory Figures, and Neon Color Spreading  

Microsoft Academic Search

A real-time visual processing theory is used to analyze real and illusory contour formation, contour and brightness interactions, neon color spreading, complementary color induction, and filling-in of discounted illuminants and scotomas. The theory also physically interprets and generalizes Land's retinex theory. These phenomena are traced to adaptive processes that overcome limitations of visual uptake to synthesize informative visual representations of

Stephen Grossberg; Ennio Mingolla

1985-01-01

369

A Redetermination of the Relative Abundances of the Isotopes of Neon, Krypton, Rubidium, Xenon, and Mercury  

Microsoft Academic Search

A careful redetermination of isotopic abundance ratios in neon, krypton, rubidium, xenon, and mercury has been made. The mass spectrometer employed was calibrated for mass discriminative effects with a synthetic argon isotope mixture made from essentially pure samples of A36 and A40. The present results together with those obtained from an earlier study on carbon, nitrogen, oxygen, argon, and potassium

Alfred O. Nier

1950-01-01

370

Capture Cross Sections of the Neon Isotopes and the S-Process Neutron Balance.  

National Technical Information Service (NTIS)

The neutron capture cross sections of the three stable neon isotopes have been measured by the time-of-flight method in the energy range from 5 to 200 keV, using hydrogen free fast liquid scintillator detectors and the Maier-Leibnitz pulse height weightin...

J. Almeida

1982-01-01

371

Studium der Stationären und Laufenden Schichtung in der Entladung in Neon Mit Hilfe eines Lokalen Hochfrequenzfeldes  

Microsoft Academic Search

Zusammenfassung Es wurde ein Verfahren zur Erregung von stationären Schichten, der Schichtungswelle und der laufenden Schichten in der Gleichstromentladung ausgearbeitet, das auf der Einwirkung eines Hochfrequenzfeldes auf einen kurzen Abschnitt der positiven Säule beruht. Dieses Verfahren wurde zum Studium aller drei angeführten Schichtungsarten in Neon benützt, insbesondere jedoch zum Studium des Zusammenhanges zwischen den laufenden und den stationären Schichten.

M. Šícha; V. Veselý; J. Studnicka; J. Prostejovský; M. Novák

1962-01-01

372

A Magnus opus: Helium, neon, and argon isotopes in a North Sea oilfield  

Microsoft Academic Search

This study of the Magnus oilfield, located in the East Shetland Basin, northern North Sea, represents the most detailed investigation of noble gas isotope systematics in a liquid hydrocarbon reservoir yet undertaken. Samples from nine producing wells across this Middle Jurassic field were taken and the helium, neon, and argon isotopic ratios and abundances in the oil were determined. Both

C. J. Ballentine; M. L. Coleman

1996-01-01

373

Cross-Relaxation Effects in the Saturation of the 6328-Å Neon-Laser Line  

Microsoft Academic Search

We report experiments which show that saturation of the inhomogeneously broadened 6328-Å neon-laser line is strongly affected by cross relaxation which tends to redistribute the excited atoms over the Maxwellian velocity distribution and thus leads to partially homogeneous line saturation. Our results for Ne20 discharges agree well with theoretical calculations based on a \\

P. W. Smith; R. Hänsch

1971-01-01

374

Mechanisms controlling the global oceanic distribution of the inert gases argon, nitrogen and neon  

Microsoft Academic Search

Dissolved inert gas measurements in the ocean yield important information about processes that occur during water mass formation. We present argon, nitrogen, and neon data from the subtropical and subpolar North Pacific and the subtropical North Atlantic. All three gases were supersaturated at the surface. In the deep ocean, Ar and N2 were undersaturated while Ne re- mained supersaturated. All

Roberta C. Hamme; Steven R. Emerson

2002-01-01

375

Reprint of: Neon interatomic potentials from scattering data and crystalline properties  

NASA Astrophysics Data System (ADS)

Interatomic potentials for Ne2 derived from recent differential elastic scattering cross section measurements and properties of solid neon are presented. Cross sections and second virial coefficients are calculated with the proposed potentials and comparisons with experiment are made. The Ne2 potential derived from scattering data only is shown to provide a good fit to the solid state data.

Farrar, J. M.; Lee, Y. T.; Goldman, V. V.; Klein, M. L.

2013-12-01

376

The Negative Glow and Faraday Dark Space in Near-Normal Neon Discharges.  

National Technical Information Service (NTIS)

Radial and axial electrostatic probe measurements have been made of the negative glow and Faraday dark space of some weakly 'anomalous' cold cathode discharges in neon at pressures near 1 torr. These have been analyzed and discussed with the aim of extend...

R. M. Reynolds W. B. Montgomery K. G. Emeleus G. A. Woolsey

1969-01-01

377

AM and FM Modulation of a Helium-Neon Laser Beam Using Acousto-Optica; Interaction.  

National Technical Information Service (NTIS)

Acoustical amplitude and frequency modulation techniques of a CW helium-neon laser beam are presented. tThe communication possibilities of this beam for both cases (AM and FM) are verified. Theories are discussed for the acoustooptical modulator and the p...

O. Unlu

1972-01-01

378

A Micro-Analysis of the Helium and Neon Contents of Air  

Microsoft Academic Search

The first part of the paper deals with the quantitative separation of gases by fractional adsorption, the theoretical conditions of which had to be investigated before a really accurate helium analysis could be undertaken. The second part describes the micro-method and apparatus used for the determination of the helium and neon contents of atmospheric air, and discusses questions affecting the

E. Gluckauf

1946-01-01

379

Heat Capacity of Submonolayers of 3He Adsorbed on Solid Neon.  

National Technical Information Service (NTIS)

The heat capacity of 3He adsorbed on solid neon was measured for coverages from 1% of monolayer capacity to a complete monolayer with high resolution. Results show that the desorption heat capacity has a maximum at 7 K. At predesorption temperatures the h...

P. Wennerstroem A. Toerne T. Lindqvist

1978-01-01

380

Acoustic Interaction with the Positive Column of a Neon Glow Discharge.  

National Technical Information Service (NTIS)

Compressive acoustic pulses were produced by an impulsive abnormal-glow discharge and the interaction of these pulses with the positive column of a dc neon glow discharge was studied. The acoustic pulses are analyzed and are found to be infinitesimal ampl...

R. D. S. Melville

1967-01-01

381

Inclusive study of 200 GeV/c pi-neon interactions  

SciTech Connect

200 GeV/c pi-neon interactions are studied in the Fermilab 30 inch bubble chamber which was filled with a neon - hydrogen mixture (31 molar % neon). Scan results and measurements of a representative event sample yield proton, gamma and pion multiplicities and single particle spectra. R was measured to be 1.21 +- 0.05 for both pi +- and pi/sup 0/. Nearly identical to lower energy measurements, R is strongly dependent on the number of observed protons in the event. KNO scaling is observed for the corrected multiplicity distributions. Scaling, however, appears violated if events with a fixed number of protons are considered. Study of the pion single particle spectra show the excess particle production of the neon target over that of hydrogen is largest in the target fragmentation region and nearly constant (1.28 +- 0.02) in the central production region. The dependence of the pion rapidity distribution on the number of protons is consistent with collisions on either one or two nucleons. The s/sup - 1/2/ dependence of the P/sub parallel/ spectra is very similar to that seen in hydrogen, with limiting fragmentation reached only for beam energies much greater than 200 GeV/c. The proton momentum distribution is energy independent with the protons carrying proportionally less of the bombarding energy as s increases.

Band, H R

1980-01-01

382

Spitzer finds cosmic neon's and sulfur's sweet spot: part III, NGC 6822  

Microsoft Academic Search

We observed several H ii regions in the dwarf irregular galaxy NGC 6822 using the infrared spectrograph on the Spitzer Space Telescope. Our aim is twofold: first, to examine the neon to sulfur abundance ratio in order to determine how much it may vary and whether or not, it is fairly `universal' second, to discriminate and test the predicted ionizing

R. H. Rubin; I. A. McNabb; J. P. Simpson; R. J. Dufour; A. W. A. Pauldrach; S. W. J. Colgan; T. W. Craven; E. D. Gitterman; C. C. Lo

2010-01-01

383

Simultaneous determination of radiative and nonradiative decay channels in the neon K shell  

Microsoft Academic Search

The photoelectron-photoion coincidence method is shown to be very successful for the quantitative investigation of the ratio of radiative to nonradiative transitions and for the ratio of single to double Auger transitions. These decay probabilities are important parameters for analytical methods as well as for theoretical descriptions. The method is demonstrated for the neon 1s decay. Especially the fluorescence yield

B. Kanngießer; M. Jainz; S. Brünken; W. Benten; Ch. Gerth; K. Godehusen; K. Tiedtke; P. van Kampen; A. Tutay; P. Zimmermann; V. F. Demekhin; A. G. Kochur

2000-01-01

384

Kinetic energy release in exciton-driven metastable decay of neon cluster ions  

Microsoft Academic Search

We analyze metastable fragmentation of mass selected neon cluster ions, produced by electron impact ionization of a neutral cluster beam under conditions that lead to isolated electronically excited species (excitons) within the cluster. We have determined metastable fractions for parent ions up to Ne20+. Moreover, the average kinetic energy of the fragment ions has been measured. The kinetic energy obtained

O. Echt; R. Parajuli; S. Matt; A. Stamatovic; P. Scheier; T. D. Märk

2002-01-01

385

Sodium-neon resonant photoexcitation soft x-ray laser experiments on Saturn  

SciTech Connect

This paper summarizes progress made at Sandia Laboratories on x-ray lasers. Experiments have demonstrated two main requirements necessary for constructing a radiation pumped soft x-ray laser: (1) a source of sufficient intensity to produce high grain and (2) creation of a significant population of neon ions close to the pump. (FSD) 11 figs.

Porter, J.; Spielman, R.; Matzen, K.; McGuire, G.; Hussey, T.

1990-01-01

386

Connected Triple Excitations in Coupled-Cluster Calculations of Hyperpolarizabilities: Neon.  

National Technical Information Service (NTIS)

We have calculated the second hyperpolarizability gamma of neon using the CCSD(T) method. The accuracy of the CCSD(T) approach has been established by explicit comparison with the single, double and triple excitation coupled-cluster (CCSDT) method using e...

J. E. Rice G. E. Scuseria T. J. Lee P. R. Taylor J. Almloef

1992-01-01

387

NEON Collaborative Data Collection Campaign at Pacific South West Site in California  

NASA Astrophysics Data System (ADS)

The National Ecological Observatory Network (NEON) is a continental-scale observatory that will collect biological, chemical and geophysical data over the continental United States in order to study biodiversity, landcover change, climate change and invasive species. In June 2013, a large-scale data collection took place over NEON's Pacific South West (PSW) site 17 in CA, USA. Data were collected in the San Joaquin Experimental Range and the Sierra National Forest. NEON's AOP (Airborne Observation Platform) acquired high spatial resolution hyperspectral data (~1m pixels), waveform lidar, discrete lidar, and RGB imagery over all three sites. A field team simultaneously collected atmospheric and vegetation inventory data, including tree locations, height, diameter-at-breast-height (DBH), species, and spectral data. The NEON collect was centered within a collaboration of multiple research entities, including NASA, Rochester Institute of Technology (RIT), University of Massachusetts (Boston; UMB, and Lowell; UML), Boston University (BU), and the University of Wisconsin, Madison (UWM). NASA's AVIRIS and MASTER sensors were flown over a wider area encompassing the NEON sites, with AVIRIS acquiring hyperspectral data (224 bands) at approximately 30m spatial resolution, and MASTER acquiring multispectral thermal data (50 bands) at approximately 50m spatial resolution. These data will be downscaled to approximate theoretical HyspIRI data (60m spatial resolution) as part of a large collection of preparatory research. Concurrently, a variety of university teams were active in the field: RIT collected ground-based lidar, leaf area index (LAI), herbaceous biomass measurements, wide-angle photographs, and spectral measurements. Data were collected over 20 80x80m sites, centered on existing 20x20m NEON sites. This data set will be used to inform synthetic scene design and to study the impact of sub-pixel structural variation on pixel-level spectral response; The BU, UMB, and UML team surveyed three sites in the Sierras with their terrestrial waveform lidar (DWEL) and collected Trac measurements of LAI, while UMB collected additional discrete ground-based lidar scans and additional forestry measures at San Joaquin and the Sierras; A team from the UWM collected leaf-level reflectance and transmission spectra and measured leaf-level gas exchange and chlorophyll fluorescence. This multifaceted collaboration, funded by the NSF NEON and NASA HyspIRI Preparatory Science programs, will support key scientific developments by combining the expertise from multiple sensing modalities. This experiment highlights the advantages of data and skills sharing in remote sensing applications. An overview of the larger effort and individual early science will be presented.

Kampe, T. U.; Leisso, N.; Krause, K.; Musinsky, J.; Petroy, S. B.; Wasser, L. A.; Cawse-Nicholson, K.; van Aardt, J. A.; Schaaf, C.; Strahler, A. H.; Serbin, S. P.

2013-12-01

388

Belowground Biomass Sampling to Estimate Fine Root Mass across NEON Sites  

NASA Astrophysics Data System (ADS)

Production of belowground biomass is an important and relatively uncharacterized component of the net primary productivity (NPP) of ecosystems. Fine root productivity makes up a significant portion of total belowground production because fine roots turn over rapidly, and therefore contribute disproportionately to annual estimates of belowground net primary productivity (BNPP). One of the major goals of the National Ecological Observatory Network (NEON) is to quantify above- and below-ground NPP at 60 sites within 20 different eco-climactic regions. NEON's Terrestrial Observation System will carry out belowground biomass sampling throughout the life of the observatory to estimate fine root production. However, belowground biomass sampling during NEON operations will be constrained to a maximum depth of 50cm. This limited depth range leaves the question of what proportion of total fine root mass is being collected and how to optimally characterize belowground biomass given sampling depth limitations. During the construction period, NEON is characterizing fine root biomass distribution at depth down to 2m at each site, as well as physical and chemical properties in each soil horizon. Each sampling unit is a pit (2m deep and approximately 1.5m wide), dug in the site's dominant vegetation type where fine root biomass sampling will also occur during Operations. To sample fine root biomass in each pit, soil samples of a known volume are taken from three vertical profiles down the face of the pit. Samples are then wet sieved to extract fine root mass, and roots are dried at 65°C for 48 hours and then weighed. The soil pit data are used to estimate the proportion of total fine root biomass from each site as a function of depth. Non-linear curves are fitted to the data to calculate total fine root mass at depth and to provide estimates of the proportion of the total fine root mass that is sampled at each site during NEON's 30 year operational sampling. The belowground biomass sampling effort during construction informs logistical constraints of sampling and generates a baseline estimate for belowground biomass across all NEON sites. In addition to informing NEON's sampling design, this continental-scale dataset will be available to the public, along with the per-horizon soil physical and chemical data. Independent researchers could use this novel resource, for example, in quantifying the contribution of fine root mass to NPP or provide insight into the relationship between soil's physical and chemical properties and belowground biomass.

Spencer, J. J.; Meier, C. L.; Abercrombie, H.; Everhart, J. C.

2013-12-01

389

The Flying University  

NASA Astrophysics Data System (ADS)

The Flying University is solo theater performance framed as an academic lecture about Marie Curie and her discovery of radium, delivered to a group of women who have gathered in secret to further their education. As the lecture proceeds, the professor brings in her own research based on a study of Esther Horsch (1905-1991) who lived on a farm in central Illinois. She introduces data from Esther's journals, personal memories, and dreams about Esther's life. The professor's investigation of radium plays at the intersections of magical and mundane, decay and the transformation of life, and the place of ambition in these two women's lives. The intention of this piece is to explore these themes, which are full of mystery, through the traces of the daily lives of Mme. Curie and Esther. Their words and photos are used as roots from which to imagine the things that echo beyond their familiar work; elemental and also fantastically radiant. The Flying University was written and performed by Catherine Friesen April 27-29, 2012 in the Center for Performance Experiment at Hamilton College as part of the University of South Carolina MFA Acting Class of 2013 showcase, Pieces of Eight.

Friesen, Catherine

390

The Light-Organ Symbiosis of Vibrio fischeri and the Hawaiian squid, Euprymna scolopes  

NSDL National Science Digital Library

This informational web page features the luminescent bacteria that live within the light organs of the bobtailed squid and the Hawaiian squid. The page includes a discussion of how symbionts and host influence each others development, bacterial genes required to successfully colonize the squid, the "venting" microenvironment, evidence for oxidative stress occurring inside the light organ, initiation of symbiosis, and the investigators who study the V. fischeri-E. scolopes symbiosis. It also features color images and links to selected reviews and research publications.

Graf, Joerg; Connecticut, University O.

391

Towards a dc SQUID read-out for the normal metal hot-electron microbolometer  

NASA Astrophysics Data System (ADS)

A prototype of SQUID read-out for current measurements at the output of a normal metal hot-electron microbolometer has been developed and tested. The system is based on serial VTT dc SQUID and input ?-metal core solenoid transformer. The achieved current resolution is 300 fA/Hz 1/2. Johnson noise of metal resistor and shot noise of tunnel junction were used for current calibration of SQUID read-out. The current noise spectra of 35 k ? SIN tunnel junction measured at different bias voltages are presented.

Tarasov, M.; Gudoshnikov, S.; Kalabukhov, A.; Seppa, H.; Kiviranta, M.; Kuzmin, L.

2002-03-01

392

14N nuclear quadrupole resonance of p-nitrotoluene using a high-Tc rf SQUID  

NASA Astrophysics Data System (ADS)

Using a high-Tc radio-frequency superconducting quantum interference device (rf SQUID), we successfully detected nuclear quadrupole resonance (NQR) at about 887 kHz for 14N in p-nitrotoluene (PNT). A normal metal transformer made of copper wire was used to improve the sensitivity of the high-Tc rf SQUID and pulse-controlled rf switches and cross diodes were inserted in the transformer to reduce the influence of the strong excitation field. The preliminary results for NQR detection using the high-Tc SQUID had a similar signal-to-noise ratio to that of using a low noise preamplifier.

He, D. F.; Tachiki, M.; Itozaki, H.

2007-03-01

393

Poisoning from “Spanish fly” (cantharidin)  

Microsoft Academic Search

Cantharidin, known popularly as Spanish fly, has been used for millennia as a sexual stimulant. The chemical is derived from blister beetles and is notable for its vesicant properties. While most commonly available preparations of Spanish fly contain cantharidin in negligible amounts, if at all, the chemical is available illicitly in concentrations capable of causing severe toxicity. Symptoms of cantharidin

David J Karras; Susan E Farrell; Richard A Harrigan; Frederick M Henretig; Laura Gealt

1996-01-01

394

Exploding Foil Flying Plate Generator,  

National Technical Information Service (NTIS)

This paper reports on work done at MRL to generate and use high velocity flying plates. The plates are generated by the pressure from an electrically burst metal foil. We examine some of the important design characteristics of the flying plate generator. ...

D. D. Richardson E. D. Northeast P. F. Ryan

1988-01-01

395

Multielemental analysis of purpleback flying squad using high resolution inductively coupled plasma-mass spectrometry (HR ICP-MS).  

PubMed

Forty-four elements were analyzed in 21 tissues of purpleback flying squid, Sthenoteuthis oualaniensis, by high resolution inductively coupled plasma-mass spectrometry (HR ICP-MS) and inductively coupled plasma atomic emission spectrophotometry (ICP-AES). Greater concentrations of V, Fe, Co, Ni, Cu, Ag, Cd, Pb, and Bi were found in liver, pancreas, and ink sac than in other tissues. Ink sac concentrated remarkable levels of Ca and Sr in addition to the above-mentioned elements. Several alkalis, alkaline earth, and rare earth elements preferentially accumulated in muscle. Among the hard tissues, accumulation of V and U in beak, Ni, Zn, and Cd in gladius and Cr in skin was prominent. K, Rb, Cs, Pb, Bi and some transition elements (V, Co, Cu, Zn, Ag, Cd) were significantly (p < 0.05) higher in the livers of adult than in juvenile squids. Sodium, alkaline earth, and rare earth elements were higher in the livers of juveniles than in adult squids. PMID:11505984

Ichihashi, H; Kohno, H; Kannan, K; Tsumura, A; Yamasaki, S I

2001-08-01

396

The set-up of a high temperature superconductor radio-frequency SQUID microscope for magnetic nanoparticle detection  

NASA Astrophysics Data System (ADS)

SQUID (superconducting quantum interference device) microscopes are versatile instruments for biosensing applications, in particular for magnetic nanoparticle detection in immunoassay experiments. We are developing a SQUID microscope based on an HTS rf SQUID magnetometer sensor with a substrate resonator. For the cryogenic set-up, a configuration was realized in which the cryostat is continuously refilled and kept at a constant liquid nitrogen level by an isolated tube connection to a large liquid nitrogen reservoir. The SQUID is mounted on top of a sapphire finger, connected to the inner vessel of the stainless steel cryostat. The vacuum gap between the cold SQUID and room temperature sample is adjusted by the precise approach of a 50 µm thin sapphire window using a single fine thread wheel. We investigated possible sensing tip configurations and different sensor integration techniques in order to achieve an optimized design. A new scheme of coupling the rf SQUID from its back to a SrTiO3 substrate resonator was adopted for the purpose of minimization of the sensor-to-sample spacing. By SQUID substrate thinning and washer size reduction, the optimum coupling conditions for back coupling were determined for different rf SQUID magnetometers prepared on LaAlO3 and SrTiO3 substrates. The SQUID microscope system is characterized with respect to its spatial resolution and its magnetic field noise. The SQUID microscope instrument will be used for magnetic nanoparticle marker detection.

Schmidt, M.; Krause, H.-J.; Banzet, M.; Lomparski, D.; Schubert, J.; Zander, W.; Zhang, Y.; Akram, R.; Fardmanesh, M.

2006-05-01

397

Resonant effects in a SQUID qubit subjected to nonadiabatic changes  

NASA Astrophysics Data System (ADS)

By quickly modifying the shape of the effective potential of a double SQUID flux qubit from a single-well to a double-well condition, we experimentally observe an anomalous behavior, namely, an alternation of resonance peaks, in the probability to find the qubit in a given flux state. The occurrence of Landau-Zener transitions as well as resonant tunneling between degenerate levels in the two wells may be invoked to partially justify the experimental results. A quantum simulation of the time evolution of the system indeed suggests that the observed anomalous behavior can be imputable to quantum coherence effects. The interplay among all these mechanisms has a practical implication for quantum computing purposes, giving a direct measurement of the limits on the sweeping rates possible for a correct manipulation of the qubit state by means of fast flux pulses, avoiding transitions to noncomputational states.

Chiarello, F.; Spilla, S.; Castellano, M. G.; Cosmelli, C.; Messina, A.; Migliore, R.; Napoli, A.; Torrioli, G.

2014-04-01

398

The transition from stiff to compliant materials in squid beaks.  

PubMed

The beak of the Humboldt squid Dosidicus gigas represents one of the hardest and stiffest wholly organic materials known. As it is deeply embedded within the soft buccal envelope, the manner in which impact forces are transmitted between beak and envelope is a matter of considerable scientific interest. Here, we show that the hydrated beak exhibits a large stiffness gradient, spanning two orders of magnitude from the tip to the base. This gradient is correlated with a chemical gradient involving mixtures of chitin, water, and His-rich proteins that contain 3,4-dihydroxyphenyl-L-alanine (dopa) and undergo extensive stabilization by histidyl-dopa cross-link formation. These findings may serve as a foundation for identifying design principles for attaching mechanically mismatched materials in engineering and biological applications. PMID:18369144

Miserez, Ali; Schneberk, Todd; Sun, Chengjun; Zok, Frank W; Waite, J Herbert

2008-03-28

399

The Transition from Stiff to Compliant Materials in Squid Beaks  

NASA Astrophysics Data System (ADS)

The beak of the Humboldt squid Dosidicus gigas represents one of the hardest and stiffest wholly organic materials known. As it is deeply embedded within the soft buccal envelope, the manner in which impact forces are transmitted between beak and envelope is a matter of considerable scientific interest. Here, we show that the hydrated beak exhibits a large stiffness gradient, spanning two orders of magnitude from the tip to the base. This gradient is correlated with a chemical gradient involving mixtures of chitin, water, and His-rich proteins that contain 3,4-dihydroxyphenyl-L-alanine (dopa) and undergo extensive stabilization by histidyl-dopa cross-link formation. These findings may serve as a foundation for identifying design principles for attaching mechanically mismatched materials in engineering and biological applications.

Miserez, Ali; Schneberk, Todd; Sun, Chengjun; Zok, Frank W.; Waite, J. Herbert

2008-03-01

400

Coupling of Retinal, Protein, and Water Dynamics in Squid Rhodopsin  

PubMed Central

The light-induced isomerization of the retinal from 11-cis to all-trans triggers changes in the conformation of visual rhodopsins that lead to the formation of the activated state, which is ready to interact with the G protein. To begin to understand how changes in the structure and dynamics of the retinal are transmitted to the protein, we performed molecular dynamics simulations of squid rhodopsin with 11-cis and all-trans retinal, and with two different force fields for describing the retinal molecule. The results indicate that structural rearrangements in the binding pocket, albeit small, propagate toward the cytoplasmic side of the protein, and affect the dynamics of internal water molecules. The sensitivity of the active-site interactions on the retinal force-field parameters highlights the coupling between the retinal molecule and its immediate protein environment.

Jardon-Valadez, Eduardo; Bondar, Ana-Nicoleta; Tobias, Douglas J.

2010-01-01

401

The Transition from Stiff to Compliant Materials in Squid Beaks  

PubMed Central

The beak of the Humboldt squid Dosidicus gigas represents one of the hardest and stiffest wholly organic materials known. As it is deeply embedded within the soft buccal envelope, the manner in which impact forces are transmitted between beak and envelope is a matter of considerable scientific interest. Here, we show that the hydrated beak exhibits a large stiffness gradient, spanning two orders of magnitude from the tip to the base. This gradient is correlated with a chemical gradient involving mixtures of chitin, water, and His-rich proteins that contain 3,4-dihydroxyphenyl-l-alanine (dopa) and undergo extensive stabilization by histidyl-dopa cross-link formation. These findings may serve as a foundation for identifying design principles for attaching mechanically mismatched materials in engineering and biological applications.

Miserez, Ali; Schneberk, Todd; Sun, Chengjun; Zok, Frank W.; Waite, J. Herbert

2009-01-01

402

A phase qubit coupled to an RF-SQUID resonator  

NASA Astrophysics Data System (ADS)

We have coupled a tunable cavity (an RF-SQUID resonator) to a phase qubit. The resonator can be used both for state transfer experiments as well as a measurement/readout device for the qubit. Specifically, it can be used in three different ways to help interrogate the state of the qubit. First, changes in the resonator frequency can be monitored in order to read out the qubit state after a conventional fast measure pulse is applied to the qubit bias flux. Second, we can perform a linear dispersive measurement of the qubit state using the coupled interaction between the qubit and the resonator. Here, the resonator will have a qubit-state dependent frequency shift. Finally, we can exploit the nonlinearity of the resonator by driving it into the bifurcated regime and performing a single- shot measurement of the state of the qubit. I will discuss the design, fabrication, and operation of this system.

Whittaker, Jed; Allman, Shane; Cicak, Katarina; Nguyen, Francois; Sirois, Adam; Teufel, John; Zakka-Bajjani, Eva; Simmonds, Raymond

2011-03-01

403

Multichannel DC SQUID sensor array for biomagnetic applications  

SciTech Connect

This paper reports on a biomagnetic multichannel system for medical diagnosis of brain and heart KRENIKON has been developed. 37 axial 2st order gradiometers - manufactured as flexible superconducting printed circuits - are arranged in a circular flat array of 19 cm diameter. Additionally, 3 orthogonal magnetometers are provided. The DC SQUIDs are fabricated in all-Nb technology, ten on a chip. The sensor system is operated in a shielded room with two layers of soft magnetic material and one layer of Al. The every day noise level is 10 fT/Hz{sup 1/2} at frequencies above 10 Hz. Within 2 years of operation in a normal urban surrounding, useful clinical applications have been demonstrated (e.g. for epilepsy and heart arrhythmias).

Hoenig, H.E.; Daalmans, G.M.; Bar, L.; Bommel, F.; Paulus, A.; Uhl, D.; Weisse, H.J. (Siemens Corp. Research, P.O. Box 3220, D8520 Eriangen (DE)); Schneider, S.; Seifert, H.; Reichenberger, H.; Abraham-Fuchs, K. (Siemens Medical Engineering Group, D8520 Eriangen (DE))

1991-03-01

404

A digital filtering scheme for SQUID based magnetocardiography  

NASA Astrophysics Data System (ADS)

Considering the properties of slow change and quasi-periodicity of magnetocardiography (MCG) signal, we use an integrated technique of adaptive and low-pass filtering in dealing with two-channel MCG data measured by high Tc SQUIDs. The adaptive filter in the time domain is based on a noise feedback normalized least-mean-square (NLMS) algorithm and the low-pass filter with a cutoff at 100Hz in the frequency domain characterized by Gaussian functions is combined with a notch at the power line frequency. In this way, both relevant and irrelevant noises in original MCG data are largely eliminated. The method may also be useful for other slowly varying quasi-periodical signals.

Zhu, Xue-Min; Ren, Yu-Feng; Yu, Hong-Wei; Zhao, Shi-Ping; Chen, Geng-Hua; Zhang, Li-Hua; Yang, Qian-Sheng

2006-01-01

405

A magnetic shield around the flux guide in a SQUID probe microscope with finite element simulation  

NASA Astrophysics Data System (ADS)

In a superconducting quantum interference device (SQUID) probe microscope, the existence of a needle with high permeability as a flux guide can increase the spatial resolution. Also, the flux guide makes it possible to measure the samples in air at room temperature. Using a finite element method (FEM), we analyzed the property of a magnetic shielding cylinder with high permeability Permalloy around the needle. Simulation results show that a cylindrical shield around the flux guide can increase the spatial resolution of the SQUID probe microscope. Also, a model of a small SQUID has been designed and the calculated result shows that the spatial resolution is higher than a SQUID with the flux guide and the shield around it.

Kong, X. Y.; Sakuta, K.; Itozaki, H.

2007-12-01

406

Bi-SQUIDs with submicron cross-type Josephson tunnel junctions  

NASA Astrophysics Data System (ADS)

We present and discuss results for the experimental evaluation of bi-SQUIDs with shunted submicron cross-type Josephson tunnel junctions characterized by low capacitance. Such a technology, meant for SQUID sensors, was developed to enable unshielded operation of the sensors and to avoid unwanted flux trapping. The obtained voltage response swing is as high as 60 µV. The observed differences between the measured and theoretically predicted voltage responses are analyzed and the possible ways to approach a triangular voltage response shape are discussed. An improved design of such bi-SQUIDs with gradiometric topology is suggested to compensate for the influence of the sizable parasitic three-junction loop, which is the main drawback of the implemented bi-SQUID topology.

Sharafiev, A.; Soloviev, I.; Kornev, V.; Schmelz, M.; Stolz, R.; Zakosarenko, V.; Anders, S.; Meyer, H.-G.

2012-04-01

407

Nanoscale multifunctional sensor formed by a Ni nanotube and a scanning Nb nanoSQUID  

NASA Astrophysics Data System (ADS)

Nanoscale magnets might form the building blocks of next generation memories. To explore their functionality, magnetic sensing at the nanoscale is key. We present a multifunctional combination of a nanometer-sized superconducting quantum interference device (nanoSQUID) and a Ni nanotube attached to an ultrasoft cantilever as a magnetic tip. By scanning the Nb nanoSQUID with respect to the Ni tube, we map out and analyze their magnetic coupling, demonstrate the imaging of an Abrikosov vortex trapped in the SQUID structure — which is important in ruling out spurious magnetic signals — and reveal the high potential of the nanoSQUID as an ultrasensitive displacement detector. Our results open a new avenue for fundamental studies of nanoscale magnetism and superconductivity.

Nagel, J.; Buchter, A.; Xue, F.; Kieler, O. F.; Weimann, T.; Kohlmann, J.; Zorin, A. B.; Rüffer, D.; Russo-Averchi, E.; Huber, R.; Berberich, P.; Fontcuberta i Morral, A.; Grundler, D.; Kleiner, R.; Koelle, D.; Poggio, M.; Kemmler, M.

2013-08-01

408

Effect of Specific Antibodies on the Excitability of Internally Perfused Squid Axons.  

National Technical Information Service (NTIS)

Giant axons from the squid Dosidicus gigas were internally perfused with rabbit antiaxoplasma antibodies and their effect upon the action potential and the membrane potential was studied. Necessary requirements for the antibodies to affect these parameter...

F. C. Huneeus H. L. Fernandez

1967-01-01

409

Properties of the Atpase System from the Sheath of Squid Giant Axons.  

National Technical Information Service (NTIS)

Membrane fractions have been isolated from the axon sheath of the squid Dosidicus gigas by differential centrifugation of hypotonic homogenates. The 100,000 g pellet, which contains disintegrated cell membranes, displayed a high Mg-, Na-, K-activated ATPa...

M. Canessa-Fischer F. Zambrano V. Riveros-Moreno

1967-01-01

410

A shot in the dark: same-sex sexual behaviour in a deep-sea squid.  

PubMed

Little is known about the reproductive habits of deep-living squids. Using remotely operated vehicles in the deep waters of the Monterey Submarine Canyon, we have found evidence of mating, i.e. implanted sperm packages, on similar body locations in males and females of the rarely seen mesopelagic squid Octopoteuthis deletron. Equivalent numbers of both sexes were found to have mated, indicating that male squid routinely and indiscriminately mate with both males and females. Most squid species are short-lived, semelparous (i.e. with a single, brief reproductive period) and promiscuous. In the deep, dark habitat where O. deletron lives, potential mates are few and far between. We suggest that same-sex mating behaviour by O. deletron is part of a reproductive strategy that maximizes success by inducing males to indiscriminately and swiftly inseminate every conspecific that they encounter. PMID:21937492

Hoving, Hendrik J T; Bush, Stephanie L; Robison, Bruce H

2012-04-23

411

Bipolar Quantum Voltage Generator Based on Zero Crossing Shapiro Steps in Asymmetric 2J-SQUIDs  

NASA Astrophysics Data System (ADS)

On an asymmetric two-junction superconducting quantum interference device (2J-SQUID) driven by one sinusoidal rf signal, the observation of zero-crossing Shapiro steps have been reported. In this paper, the loop inductance, L and the ratio of critical currents of Josephson junctions of the 2J-SQUID were optimized by a simulation. Using three voltage states those this asymmetric 2J-SQUID has, the bipolar quantum voltage generator that has three asymmetric 2J-SQUIDs and two control lines, was designed based on obtained parameters. Within the bias current -voltage curves with seven different combinations of the control currents, seven quantized voltages were obtained at the zero bias current.

Moriya, Masataka; Kondo, Naoki; Mizugaki, Yoshinao

412

Magnetoencephalography - the Use of Multi-SQUID Systems for Noninvasive Brain Research  

NASA Astrophysics Data System (ADS)

Some of the basic concepts of magnetoencephalography (MEG) and neuromagnetic instrumentation are reviewed. Examples of multichannel SQUID magnetometers and results of measurements with them are presented. Current trends in MEG instrument development are discussed.

Knuutila, Jukka

1988-01-01

413

Analytical Calculation of Gain and Noise of DC Squid Microwave Amplifier  

NASA Astrophysics Data System (ADS)

The dc SQUID microwave amplifier, based on Josephson junctions, is employed in a wide spectrum of applications ranging from dark matter detection to the readout of superconducting qubits. A crucial advantage offered by this device is the separation of input and output channels, unlike conventional Josephson parametric amplifiers, so that it does not require a nonreciprocal device such as a circulator for its operation. The mechanism underlying the directional gain in the SQUID microwave amplifier, however, has so far remained elusive. We present a first principles, analytical calculation, based on scattering theory, of a practical SQUID amplifier which elucidates the underlying nonlinear mode mixing responsible for the directional operation of the device. The gain and quantum noise characteristics of a SQUID operated as a microwave voltage amplifier are discussed. Work supported by IARPA and ARO (AK, MHD and JC) and NSF (AK and MHD).

Kamal, Archana; Devoret, Michel; Clarke, John

2012-02-01

414

Advances in the Measurement of rf Power and Attenuation Using SQUIDS.  

National Technical Information Service (NTIS)

Stable SQUIDs were developed with preset junctions which survive thermal cycling and mechanical shock. Further work is required to arrive at a version suitable for precise rf measurements. A 'breadboard' system was assembled capable of measuring rf power ...

R. A. Kamper M. B. Simmonds R. T. Adair C. A. Hoer

1974-01-01

415

Features governing symbiont persistence in the squid-vibrio association.  

PubMed

Experimental studies of the interaction between host and symbiont in a maturing symbiotic organ have presented a challenge for most animal-bacterial associations. Advances in the rearing of the host squid Euprymna scolopes have enabled us to explore the relationship between a defect in symbiont light production and late-stage development (e.g. symbiont persistence and tissue morphogenesis) by experimental colonization with specific strains of the symbiont Vibrio fischeri. During the first 4 weeks postinoculation of juvenile squid, the population of wild-type V. fischeri increased 100-fold; in contrast, a strain defective in light production (?lux) colonized normally the first day, but exhibited an exponential decline to undetectable levels over subsequent weeks. Co-colonization of organs by both strains affected neither the trajectory of colonization by wild type nor the decline of ?lux levels. Uninfected animals retained the ability to be colonized for at least 2 weeks posthatch. However, once colonized by the wild-type strain for 5 days, a subsequent experimentally induced loss of the symbionts could not be followed by a successful recolonization, indicating the host's entry into a refractory state. However, animals colonized by the ?lux before the loss of their symbionts were receptive to recolonization. Analyses of animals colonized with either a wild-type or a ?lux strain revealed slight, if any, differences in the developmental regression of the ciliated light-organ tissues that facilitate the colonization process. Thus, some other feature(s) of the ?lux strain's defect also may be responsible for its inability to persist, and its failure to induce a refractory state in the host. PMID:24118200

Koch, Eric J; Miyashiro, Tim; McFall-Ngai, Margaret J; Ruby, Edward G

2014-03-01

416

Ontogenetic changes in fibrous connective tissue organization in the oval squid, Sepioteuthis lessoniana Lesson, 1830.  

PubMed

Ontogenetic changes in the organization and volume fraction of collagenous connective tissues were examined in the mantle of Sepioteuthis lessoniana, the oval squid. Outer tunic fiber angle (the angle of a tunic collagen fiber relative to the long axis of the squid) decreased from 33.5 degrees in newly hatched animals to 17.7 degrees in the largest animals studied. The arrangement of intramuscular collagen fiber systems 1 (IM-1) and 2 (IM-2) also changed significantly during ontogeny. Because of the oblique trajectory of the IM-1 collagen fibers, two fiber angles were needed to describe their organization: (1) IM-1(SAG), the angle of an IM-1 collagen fiber relative to the squid's long axis when viewed from a sagittal plane and (2) IM-1(TAN), the angle of an IM-1 collagen fiber relative to the squid's long axis when viewed from a plane tangential to the outer curvature of the mantle. The sagittal component (IM-1(SAG)) of the IM-1 collagen fiber angle was lowest in hatchling squid (32.7 degrees ) and increased exponentially during growth to 43 degrees in squid with a dorsal mantle length (DML) of 15 mm. In squid larger than 15 mm DML, IM-1(SAG) fiber angle did not change. The tangential component (IM-1(TAN)) of IM-1 collagen fiber angle was highest in hatchling squid (39 degrees ) and decreased to 32 degrees in the largest squid examined. IM-2 collagen fiber angle (the angle of an IM-2 collagen fiber relative to the outer surface of the mantle) was lowest in hatchling squid (34.6 degrees ) and increased exponentially to about 50 degrees in 15-mm DML animals. In squid larger than 15 mm DML, IM-2 fiber angle increased slightly with size. The volume fraction of collagen in IM-1 and IM-2 increased 68 and 36 times, respectively, during growth. The ontogenetic changes in the organization of collagen fibers in the outer tunic, IM-1, and IM-2 may lead to ontogenetic differences in the kinematics of mantle movement and in elastic energy storage during jet locomotion. PMID:11687386

Thompson, J T; Kier, W M

2001-10-01

417

Investigation of Helium-Cooled Planar Transformer-Coupled SQUID Magnetometer  

NASA Astrophysics Data System (ADS)

We investigated helium-cooled planar transformer-coupled SQUID magnetometers with regard to their field resolution ?B by varying the SQUID loop inductance Ls, input coils and the pick-up loop Lp. It was found that the pick-up-loop area Ap is the most important parameter for ?B of transformer-coupled magnetometers. ?B with Ap = 10 × 10 mm2 reached about 3 fTA/squareHz, even using direct readout scheme without any feedback circuitries.

Zeng, Jia; Zhang, Yi; Mück, Michael; Liu, Chao; Krause, Hans-Joachim; Kong, Xiangyan; Xie, Xiaoming; Offenhäusser, Andreas

2014-05-01

418

HTS SQUID system with Joule-Thomson cryocooler for eddy current nondestructive evaluation of aircraft structures  

Microsoft Academic Search

For the detection of deep-lying flaws in aircraft structures, an eddy current system in conjunction with a planar SQUID gradiometer is being developed. The need for a mobile system imposes additional requirements on cooling regarding mobility, operation independent of spatial orientation, and handling. We present results on the operation of HTS SQUIDs with the commercial Joule-Thomson-cryocooler KC 100 (“cryotiger”) by

R. Hohmann; H.-J. Krause; H. Soltner; H. Zhang; C. A. Copetti; H. Bousack; A. I. Braginski; M. I. Faley

1997-01-01

419

SQUID gradiometer for ultra-low temperature magnetic micro-calorimeter  

Microsoft Academic Search

First-order integrated planar SQUID gradiometers with pick-up loops of 40 µm in diameter and a baseline of 200 µm were designed specially for the readout of signals from magnetic micro-calorimeters. The SQUID has to operate in magnetic fields up to 5 mT and at temperatures down to 7 mK. The design is a first step to develop a multi-pixel x-ray

V. Zakosarenko; R. Stolz; L. Fritzsch; H.-G. Meyer; A. Fleischmann; C. Enns

2003-01-01

420

Understanding the accumulation features of POPs in squid from the offshore waters of southeast Korea  

Microsoft Academic Search

In this study we investigated the current contamination status and accumulation features of POPs in Korean offshore waters\\u000a using Japanese common squid as a biomonitoring organism. Concentrations of organochlorine compounds (OCs), such as polychlorinated\\u000a biphenyls (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), chlordane compounds (CHLs), and hexachlorocyclohexanes\\u000a (HCHs) were determined in different organs of squid of both sexes and of

Jong Ho Won; Sang Hee Hong; Won Joon Shim; Un Hyuk Yim; Gi Beum Kim

2010-01-01

421

EFFECT OF pH AND TEMPERATURE ON JUMBO SQUID PROTEINS  

Microsoft Academic Search

Evaluation of the effect of pH (2 to 13) and temperature (0 to 50C) on functional properties of jumbo squid proteins was performed, followed by a 2 ¥ 3 factorial design for producing squid protein hydrolysates bearing useful functional properties. In particular, the effects of pH (8, 9 and 10) and tem- perature (30, 35, 40C) were evaluated. Alcalase and

G. DE LA FUENTE-BETANCOURT; F. GARCÍA-CARREÑO; M. A. NAVARRETE DEL TORO; J. H. CÓRDOVA-MURUETA

2009-01-01

422

Contribution of pilA to Competitive Colonization of the Squid Euprymna scolopes by Vibrio fischeri  

Microsoft Academic Search

Vibrio fischeri colonizes the squid Euprymna scolopes in a mutualistic symbiosis. Hatchling squid lack these bacterial symbionts, and V. fischeri strains must compete to occupy this privileged niche. We cloned a V. fischeri gene, designated pilA, that contributes to colonization competitiveness and encodes a protein similar to type IV-A pilins. Unlike its closest known relatives, Vibrio cholerae mshA and vcfA,

Eric V. Stabb; Edward G. Ruby

2003-01-01

423

Characterization of the Bacterial Diversity in Indo-West Pacific Loliginid and Sepiolid Squid Light Organs  

PubMed Central

Loliginid and sepiolid squid light organs are known to host a variety of bacterial species from the family Vibrionaceae, yet little is known about the species diversity and characteristics among different host squids. Here we present a broad-ranging molecular and physiological analysis of the bacteria colonizing light organs in loliginid and sepiolid squids from various field locations of the Indo-West Pacific (Australia and Thailand). Our PCR-RFLP analysis, physiological characterization, carbon utilization profiling, and electron microscopy data indicate that loliginid squid in the Indo-West Pacific carry a consortium of bacterial species from the families Vibrionaceae and Photobacteriaceae. This research also confirms our previous report of the presence of Vibrio harveyi as a member of the bacterial population colonizing light organs in loliginid squid. pyrH sequence data were used to confirm isolate identity, and indicates that Vibrio and Photobacterium comprise most of the light organ colonizers of squids from Australia, confirming previous reports for Australian loliginid and sepiolid squids. In addition, combined phylogenetic analysis of PCR-RFLP and 16S rDNA data from Australian and Thai isolates associated both Photobacterium and Vibrio clades with both loliginid and sepiolid strains, providing support that geographical origin does not correlate with their relatedness. These results indicate that both loliginid and sepiolid squids demonstrate symbiont specificity (Vibrionaceae), but their distribution is more likely due to environmental factors that are present during the infection process. This study adds significantly to the growing evidence for complex and dynamic associations in nature and highlights the importance of exploring symbiotic relationships in which non-virulent strains of pathogenic Vibrio species could establish associations with marine invertebrates.

Guerrero-Ferreira, Ricardo; Gorman, Clayton; Chavez, Alba A.; Willie, Shantell

2013-01-01

424

Application of an RF-SQUID to Detect Magnetic Particles Used in Immunoassays  

Microsoft Academic Search

We developed a detection system for magnetic particles based on a two-hole bulk RF-SQUID. In this system, the particles were detected by measuring the magnetic flux change caused by the displacement of magnetized samples across the SQUID hole. Commercial silica coated magnetic particles of iron oxide were used in the experiments. Dilutions from a 50 micrograms\\/milliliter dispersion of particles were

H. R. Carvalho; A. C. Bruno; S. R. W. Louro; P. Costa Ribeiro

2007-01-01

425

The potential impacts of climate change on inshore squid: biology, ecology and fisheries  

Microsoft Academic Search

Squid are important components of many marine ecosystems from the poles to the equator, serving as both important predators\\u000a and prey. Novel aspects of their growth and reproduction mean that they are likely to play an important role in the changing\\u000a oceans due to climate change. Virtually every facet of squid life-history examined thus far has revealed an incredible capacity

Gretta T. Pecl; George D. Jackson

2008-01-01

426

A SQUID biomagnetometer system for measurement of spinal cord evoked magnetic fields  

NASA Astrophysics Data System (ADS)

We developed a 24-channel superconducting quantum interference devices (SQUIDs) biomagnetometer system for the measurement of the evoked magnetic field from stimulated spinal cords. The system uses composite LTc SQUID gradiometers and can observe the three-dimensional components of the magnetic field. With the system, we could successfully record the evoked magnetic fields corresponding to neuronal signals transmitting in the spinal cord of a cat.

Adachi, Y.; Uehara, G.; Kawai, J.; Kawabata, S.; Okubo, H.; Komori, H.; Kado, H.

2001-12-01

427

The Application of a Helium-Neon Laser to the Measurement of Surface Displacement, Surface Vibration, and Random Surface Motion.  

National Technical Information Service (NTIS)

Applications of helium-neon lasers to holographic interferometry for vibration mode measurement and nondestructive surface control are discussed. The direct recording of velocity and displacement of a surface with respect to a reference point is described...

T. J. Struys

1971-01-01

428

Development of a HTS SQUID module for use with an external pickup coil  

NASA Astrophysics Data System (ADS)

We have developed HTS SQUID modules applicable to various systems, such as nondestructive evaluation and low-field NMR/MRI systems. The SQUID module consists of a directly coupled HTS planar gradiometer and a HTS multi-turn input coil, which are fabricated on separate substrates and stacked with a flip-chip configuration. Two types of input coils, 26-turns and 59-turns, are fabricated. The SQUID module is mounted on a printed circuit board with large electrodes for soldering to the external pickup coil. The mutual inductances between the input coil and SQUID varied from 0.5 to 2.3 nH, depending on the number of turns of the input coil and the inductance of the SQUID. The SQUID modules with an external pickup coil made of normal metal showed a lower cut-off frequency of 45 Hz and a field noise as low as 35 fT Hz-1/2 (>4 kHz).

Tsukamoto, A.; Adachi, S.; Oshikubo, Y.; Tanabe, K.; Enpuku, K.

2013-01-01

429

Nano-sized SQUID-on-tip for scanning probe microscopy  

NASA Astrophysics Data System (ADS)

We present a SQUID of novel design, which is fabricated on the tip of a pulled quartz tube in a simple 3-step evaporation process without need for any additional processing, patterning, or lithography. The resulting devices have SQUID loops with typical diameters in the range 75-300 nm. They operate in magnetic fields up to 0.6 T and have flux sensitivity of 1.8 ??0/Hz1/2 and magnetic field sensitivity of 10-7 T/Hz1/2, which corresponds to a spin sensitivity of 65 ?B/Hz1/2 for aluminum SQUIDs. The shape of the tip and the small area of the SQUID loop, together with its high sensitivity, make our device an excellent tool for scanning SQUID microscopy: With the SQUID-on-tip glued to a tine of a quartz tuning fork, we have succeeded in obtaining magnetic images of a patterned niobium film and of vortices in a superconducting film in a magnetic field.

Finkler, A.; Vasyukov, D.; Segev, Y.; Neeman, L.; Anahory, Y.; Myasoedov, Y.; Rappaport, M. L.; Huber, M. E.; Martin, J.; Yacoby, A.; Zeldov, E.

2012-12-01

430

Noise characteristics of a dc SQUID with a resistively shunted inductance. II. Optimum damping  

SciTech Connect

Effects of a damping resistance on noise characteristics of a dc SQUID are studied theoretically, where the damping resistance is in shunt with a loop inductance of the SQUID. An analytical expression for the energy resolution of the SQUID is obtained, with which the relation between the damping resistance and the energy resolution is studied in detail. It is shown that an optimum value of the damping resistance exists, which is determined by the tradeoff between the improvement of the transfer function and the additional noise due to the damping resistance. Optimum values of the damping resistance are about twice the shunt resistance of the SQUID and vary slightly with SQUID modulation parameter ..beta... For optimum damping, the energy resolution is improved, compared with the case without the damping resistance. This means that the SQUID with large ..beta.. can be used without significant degradation of the performance, i.e., the previous restriction of ..beta.. = 1 can be loosened. The analytical results agree quantitatively with numerical ones.

Enpuku, K.; Yoshida, K.; Kohjiro, S.

1986-12-15

431

Dependence of low frequency flux noise on SQUID-washer dimensions  

NASA Astrophysics Data System (ADS)

The 1/f spectral density of low frequency magnetic flux noise at 1 Hz in dc SQUIDs and qubits varies slowly with the dimensions of the superconducting loop, in reasonably good agreement with predictions. Previous measurements on SQUIDs fabricated from a variety of superconductors under different conditions and in a variety of geometries, however, showed that the slope of the power spectrum varied considerably. We report flux noise measurements on six resistively-shunted dc SQUIDs fabricated simultaneously on a single Si chip using a Nb-trilayer process. The noise spectra of all six devices were measured using a SQUID in a single cool-down of our dilution refrigerator. The linewidths of the SQUID loops were varied systematically by a factor of more than 30. The variation in noise power at 1 Hz was small compared with the variation in line width, while the slope varied significantly, from approximately -0.5 to -1. Furthermore, for a given SQUID, the slope depended on temperature.

Birenbaum, J.; Anton, S. M.; Fefferman, A. D.; O'Kelley, S. R.; Clarke, J.; Cho, H.-M.; Hilton, G. C.; Irwin, K. D.; Wellstood, F. C.

2011-03-01

432

Measurement of electron-impact excitation cross sections out of the neon 3P2 metastable level  

Microsoft Academic Search

We have measured cross sections for the electron-impact excitation out of the metastable levels of neon into the ten levels of the 2p53p configuration. Two sources of metastable neon atoms were used, a hollow-cathode discharge and a fast beam formed via near-resonant charge exchange. Both sources produce a mixed target of Ne in both (3P0 and 3P2) metastable levels. For

John B. Boffard; M. L. Keeler; Garrett A. Piech; L. W. Anderson; Chun C. Lin

2001-01-01

433

Helium–Neon Laser Irradiation Stimulates Migration and Proliferation in Melanocytes and Induces Repigmentation in Segmental-Type Vitiligo  

Microsoft Academic Search

Low-energy helium–neon lasers (632.8 nm) have been employed in a variety of clinical treatments including vitiligo management. Light-mediated reaction to low-energy laser irradiation is referred to as biostimulation rather than a thermal effect. This study sought to determine the theoretical basis and clinical evidence for the effectiveness of helium–neon lasers in treating vitiligo. Cultured keratinocytes and fibroblasts were irradiated with

Hsin-Su Yu; Chieh-Shan Wu; Chia-Li Yu; Ying-Hsien Kao; Min-Hsi Chiou

2003-01-01

434

Laser optogalvanic spectroscopy of neon in a discharge plasma and modeling and analysis of rocket plume RF-line emissions  

Microsoft Academic Search

The Optogalvanic Effect (OGE) of neon in a hollow cathode discharge lamp has been investigated both experimentally and theoretically. A tunable dye laser was tuned to several 1si -- 2pj neon transitions and the associated time--resolved optogalvanic (OG) spectral waveforms recorded corresponding to the DeltaJ = DeltaK = 0, +\\/-1 selection rules and modeled using a semi-empirical model. Decay rate

Kayode I. Ogungbemi

2010-01-01

435

Leaching of saltstones containing fly ash  

Microsoft Academic Search

Two types of fly ash were incorporated in saltstones designed for potential encapsulation of Savannah River Plant low level defense waste. These fly ashes have some cementitious properties while at the same time their presence in substitution for cement slows early hydration. Class C fly ash has a high calcium content and is considered cementitious; Class F fly ash has

M. W. Barnes; D. M. Roy; C. A. Langton

1985-01-01

436

Dewatered sewage biosolids provide a productive larval habitat for stable flies and house flies (Diptera: Muscidae).  

PubMed

Species diversity and seasonal abundance of muscoid flies (Diptera: Muscidae) developing in biosolid cake (dewatered biosolids) stored at a wastewater treatment facility in northeastern Kansas were evaluated. Emergence traps were deployed 19 May through 20 October 2009 (22 wk) and 27 May through 18 November 2010 (25 wk). In total, 11,349 muscoid flies were collected emerging from the biosolid cake. Stable flies (Stomoxys calcitrans (L.)) and house flies (Musca domestica (L.)), represented 80 and 18% of the muscoid flies, respectively. An estimated 550 stable flies and 220 house flies per square-meter of surface area developed in the biosolid cake annually producing 450,000 stable flies and 175,000 house flies. Stable fly emergence was seasonally bimodal with a primary peak in mid-July and a secondary peak in late August. House fly emergence peaked with the first stable fly emergence peak and then declined gradually for the remainder of the year. House flies tended to emerge from the biosolid cake sooner after its deposition than did stable flies. In addition, house fly emergence was concentrated around midsummer whereas stable fly emergence began earlier in the spring and continued later into the fall. Biosolid age and temperature were the most important parameters affecting emergence for house flies and stable flies, whereas precipitation was not important for either species. This study highlights the importance of biosolid cake as a larval developmental habitat for stable flies and house flies. PMID:22493845

Doud, C W; Taylor, D B; Zurek, L

2012-03-01

437

Detection of internal cracks and delamination in carbon-fiber-reinforced plastics using SQUID-NDI system  

Microsoft Academic Search

Recently, thick boards of carbon-fiber-reinforced plastic (CFRP) are often used in space crafts and space structures. Nondestructive inspection (NDI) using superconducting quantum interference device (SQUID) is a prospective NDI method for the thick CFRP materials. To estimate the potential of SQUID-NDI for detection of deep-lying defects in CFRP, the skin effect must be clarified. So we applied a SQUID-NDI method

Y. Hatsukade; N. Kasai; M. Kurosawa; R. Kawai; H. Takashima; F. Kojima; A. Ishiyama

2002-01-01

438

A digital flux-locked loop for high temperature SQUID magnetometer and gradiometer systems with field cancellation  

SciTech Connect

The SQUID sensor is typically operated in a null detector mode where an analogue flux-locked-loop, FLL, provides a negative feedback to maintain linear operation. The modulated SQUID signal is amplified, filtered, demodulated, and integrated in the FLL. The resulting analog signal is a measure of the magnetic field and noise at the SQUID and is also fed back to the modulation and feedback (M & F) coil to null the flux at the SQUID to maintain the linear operating point. Thus, the FLL output signal is proportional to the change in magnetic field at the SQUID pickup coil, provided the slew rate and dynamic range of the SQUID and FLL system are not exceeded. The goal of the work is to advance technologies needed for a practical fieldable SQUID biomagnetic sensor. We used HTC SQUIDs to realize the benefits noted above. We also implemented the FLL algorithm on a digital-signal-processor (DSP) to realize a number of benefits including (1) software control of noise filtering and background rejection to enable unshielded use of SQUID sensors, (2) flux quanta countin and resetting SQUID operating point to increase system slew rate and dynamic range, (3) programmable FLL adaptable to numerous specific applications, (4) digital signal output (up to 32-bit precision), and (5) reduced FLL package cost. This paper presents results of external signal rejection for a sensor system using HTC SQUIDs, preamplifier circuit, and DSP FLL designed and built at our laboratory. We also note a companion paper in these proceedings and other references to the use of DSP in SQUID applications.

Kraus, R.H. Jr.; Bracht, R.; Flynn, E.R. [and others

1996-12-01

439

Studies of Phlebotomine Sand Flies.  

National Technical Information Service (NTIS)

Psychodid sand flies in the subfamily Phlebotominae are medically important, hematophagus insects which are widely distributed and often abundant in the tropics. About 550 species in six genera are known with over half occurring in the New World. The lite...

D. G. Young G. B. Fairchild

1973-01-01

440

Interactive Fly: CNS Expression Images  

NSDL National Science Digital Library

In situ images from an award-winning and comprehensive site, The Interactive Fly. Entering through an expression pattern, this site thoroughly discusses each genes and shows its expression relative to other genes at this stage.

PhD Thomas B Brody (NIH Laboratory of Neurochemistry)

2006-12-12

441

Interactive Fly: Germ Band Extension  

NSDL National Science Digital Library

In situ images from an award-winning and comprehensive site, The Interactive Fly. Entering through an expression pattern, this site thoroughly discusses each genes and shows its expression relative to other genes at this stage.

PhD Thomas B Brody (NIH Laboratory of Neurochemistry)

2006-12-12

442

Mediterranean Fruit Fly Action Plan.  

National Technical Information Service (NTIS)

This action plan provides guidelines and actions for the eradication of a Mediterranean fruit fly (Medfly) infestation. This action plan supplements information contained in the Medfly Program Manual, Plant Protection and Quarantine (PPQ) Treatment Manual...

2004-01-01

443

Managing the Fruit Fly Experiment.  

ERIC Educational Resources Information Center

Describes a sophisticated version of the fruit fly experiment for teaching concepts about genetics to biology students. Provides students with the opportunity to work with live animals over an extended period. (JRH)

Jeszenszky, Arleen W.

1997-01-01

444

Monocular Diplopia in Flying Personnel.  

National Technical Information Service (NTIS)

Fifteen cases of monocular diplopia or polyopia in US Air Force flying personnel are reported. All appear due to optical abberations or physiologic variations within the refracting elements of the eye. In most cases this symptom was compatible with excell...

K. A. Stampfer T. J. Tredici

1974-01-01

445

Symposium on Unidentified Flying Objects.  

National Technical Information Service (NTIS)

The document is comprised of the proceedings of hearings before the U. S. House of Representatives Committee on Science and Astronautics, held on 29 July 1968, concerning physical, psychological, sociological, and technical aspects of unidentified flying ...

1968-01-01

446

Spectroscopy of High-L N = 10 Rydberg States of Carbon, Oxygen, and Neon.  

NASA Astrophysics Data System (ADS)

The high angular momentum fine structure of the n = 10 to 27 transitons in neutral Carbon, Oxygen, and Neon has been measured using Resonant Excitation Stark Ionization Spectroscopy (RESIS). This structure has been interpreted in terms of an effective polarization potential model to allow extraction of the quadrupole moments and dipole polarizibilities of the singly charged ion in each species to a precision of 0.2%. Further radio frequency studies in n = 10 Oxygen and Neon have directly determined the relative energies of high angular momentum fine structure levels to a precision of better than 0.3 MHz, allowing for greater precision in extraction of these core parameters. The RF data also allows the first test of predicted geometric phase effects in Rydberg atoms with a P-state core.

Ward, Ralph Franklin, Jr.

447

The infrared spectrum of NN···CO+ trapped in solid neon.  

PubMed

Codeposition of a Ne:N(2):CO = 200:1:1 mixture at 4.3 K with a beam of very pure neon atoms excited to their energy levels between 16.6 and 16.85 eV leads to stabilization in the resulting solid of sufficient NNCO(+) for detection of its NN- and CO-stretching vibration fundamentals. Detailed isotopic substitution studies and density functional calculations for the various isotopologues support the identification of NNCO(+) and permit estimation of the positions of two of its low-frequency fundamentals. A sufficient concentration of NOCN is also stabilized in the neon matrix for detection of its NO-stretching vibrational fundamental. PMID:22168694

Thompson, Warren E; Jacox, Marilyn E

2011-12-14

448

[Reactivation of superoxide dismutase by the helium-neon laser irradiation].  

PubMed

When incubating SOD for two hours in the buffer with pH 6.0 practically complete loss of the activity of enzyme was observed at insignificant changes of the absorption spectra in the region of 450 and 680 nm. Irradiation of SOD solution with helium-neon laser resulted in the dose-dependent reduction of spectral and enzymic properties. Similar effect of the red light was also observed when SOD was inactivated with hydrogen peroxide: laser irradiation brought about the reduction of initial absorption spectrum of the enzyme. One can believe that the therapeutic effect of helium-neon laser radiation is conditioned, at least partially, by photochemical reactivation of SOD inactivated under pathological conditions (inflammation, hypoxia) in the tissues. PMID:3191186

Gorbatenkova, E A; Azizova, O A; Vladimirov, Iu A

1988-01-01

449

Angle-resolved Auger electron spectra induced by neon ion impact on aluminum  

NASA Technical Reports Server (NTRS)

Auger electron emission from aluminum bombarded with 1 to 5 keV neon ions was studied by angle-resolved electron spectroscopy. The position and shape of the spectral features depended on the incident ion energy, angle of ion incidence, and electron take-off angle with respect to the aluminum surface. These spectral dependencies were interpreted in terms of the Doppler shift given to the Auger electron velocity by the excited atom ejected into the vacuum. For oblique ion incidence it is concluded that a flux of high energy atoms are ejected in a direction close to the projection of the ion beam on the target surface. In addition, a new spectral feature was found and identified as due to Auger emission from excited neon in the aluminum matrix.

Pepper, S. V.; Aron, P. R.

1986-01-01

450

Prediction of thermal acoustic oscillations (TAOs) in the CLAES solid CO2/neon system  

NASA Technical Reports Server (NTRS)

Results are presented of a study initiated to investigate the possibility that the existence of thermal acoustic oscillations (TAOs) in the Cryogenic Limb Atmospheric Etalon Spectrometer (CLAES) neon plumbing system ground configuration could be the cause of higher-than-predicted heat rates measured during thermal ground testing. Tests were conducted between warm boundary temperatures ranging from 40 to 100 K, which simulated the actual test conditions of the CLAES CO2/neon system. TAOs were observed between 6 and 106 Torr, which agreed with the analytical predictions, and verified the possible existence of TAOs in the CLAES system during ground testing. The presence of TAOs was eventually confirmed in the CLAES system during a subsequent thermal test and were determined to have caused the higher heat rates measured during the prior thermal test.

Spradley, I. E.; Yuan, S. W. K.

1991-01-01

451

Evidence of strong projectile-target-core interaction in single ionization of neon by electron impact  

SciTech Connect

The momentum distributions of recoil ions were measured in the single ionization of neon by electron impact at incident energies between 80 and 2300 eV. It was found that there are a noticeable number of recoil ions carrying large momenta, and the relative contributions of these ions becomes more pronounced with the further decrease of incident electron energy. These observed behaviors indicate that there is a strong projectile-target-core interaction in the single-ionization reaction. By comparing our results with those of electron-neon elastic scattering, we concluded that the elastic scattering of the projectile electron on the target core plays an important role at low and intermediate collision energies.

Yan, S.; Zhang, P.; Xu, S. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Graduate School of Chinese Academy of Sciences, Beijing 100049 (China); Ma, X.; Zhang, S. F.; Zhu, X. L.; Feng, W. T.; Liu, H. P. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

2010-11-15

452

The isotopic and elemental abundances of neon nuclei accelerated in solar flares  

NASA Technical Reports Server (NTRS)

The relative isotopic abundances of Ne-20 and Ne-22 in seven solar flares were determined from measurements of the satellite IMP 8, yielding the ratio Ne-20/Ne-22 = 7.7 (+2.3, -1.5) for solar chromospheric matter. This value is in agreement with the ratio for the component neon-A (the 'primordial' component) found in carbonaceous chondrites. An elemental abundance ratio Ne/O = 0.14 + or - 0.01 also has been obtained which agrees closely with earlier reported measurements. It is shown that the effects of preferential acceleration relative to solar-system abundances with increasing charge number observed for some solar flares - though biasing the elemental ratio - does not appear to influence the neon isotopic abundances.

Dietrich, W. F.; Simpson, J. A.

1979-01-01

453

Crystal structure and encapsulation dynamics of ice II-structured neon hydrate.  

PubMed

Neon hydrate was synthesized and studied by in situ neutron diffraction at 480 MPa and temperatures ranging from 260 to 70 K. For the first time to our knowledge, we demonstrate that neon atoms can be enclathrated in water molecules to form ice II-structured hydrates. The guest Ne atoms occupy the centers of D2O channels and have substantial freedom of movement owing to the lack of direct bonding between guest molecules and host lattices. Molecular dynamics simulation confirms that the resolved structure where Ne dissolved in ice II is thermodynamically stable at 480 MPa and 260 K. The density distributions indicate that the vibration of Ne atoms is mainly in planes perpendicular to D2O channels, whereas their distributions along the channels are further constrained by interactions between adjacent Ne atoms. PMID:25002464

Yu, Xiaohui; Zhu, Jinlong; Du, Shiyu; Xu, Hongwu; Vogel, Sven C; Han, Jiantao; Germann, Timothy C; Zhang, Jianzhong; Jin, Changqing; Francisco, Joseph S; Zhao, Yusheng

2014-07-22

454

Tempus Fugit: Time Flies  

NSDL National Science Digital Library

This online exhibit from a prominent American museum explores the character of time -- its impact on our daily lives and its ability to shape and reform human consciousness. Tempus Fugit: Time Flies is a superb exhibit from the Nelson Atkins Museum of Art that uses items from the museum to exemplify different understandings of time. The exhibit features sections on 20th Century Time, World Times, and Conservation Time. Twentieth-century time considers the changing nature of time in the technological age by examining the innovations in graphic and plastic arts inspired by an altered sense of time. The exhibit includes works by Muybridge, Edward Hopper, Salvador Dali, Kandinsky, Rothko, Roy Lichtenstein, and others. The second section, World Times, focuses on the different conceptions of time embodied in art from primitive times to the present and ranges from ancient Native American to Medieval Europe to ancestral Africa to the deeply cosmological perceptions of time in ancient Indian civilizations. Conservation Time takes visitors behind the scenes to see how conservation science can uncover the history of a work's composition and the changes wrought upon it over the course of its lifetime. The Website also offers ideas for teaching using the exhibits. In sum, this is an elegantly constructed and intelligent Website. To be sure, users will want to set aside some time for it as the graphics enforce their own meditative pace upon the viewer.

455

Lattice dynamics of solid neon at 6.5 and 23.7 K  

Microsoft Academic Search

The low-frequency phonons of fcc neon have been studied along the high-symmetry directions at both 6.5 and 23.7 K (melting point, 24.6 K) using inelastic neutron scattering on a stress-free single crystal grown at a pressure near one bar. At 23.7 K the zero-sound-wave velocities are approximately 2.5% larger than the first-sound-wave velocities measured by Brillouin scattering. The sign of

Y. Endoh; G. Shirane; J. Skalyo Jr.

1975-01-01

456

Nuclear attenuation of fast hadrons produced in charged-current ? and interactions in neoninteractions in neon  

Microsoft Academic Search

The production of hadrons in charged-current (anti)neutrino interactions is studied with the bubble chamber BEBC exposed to\\u000a the CERN (anti)neutrino wide-band beam. Fast-hadron production in a neon target is found to be attenuated as compared to that\\u000a in a hydrogen target. This feature is discussed within theoretical models based on the idea of a hadron formation length.\\u000a The experimental results

W. Burkot; T. Coghen; J. Czy?ewski; W. Wittek; M. Aderholz; J. Guy; G. T. Jones; U. F. Katz; P. Marage; D. R. O. Morrison; G. Myatt; N. Schmitz; W. Venus

1996-01-01

457

Nuclear Attenuation of Fast Hadrons Produced in Charged-Current Neutrino and Antineutrino Interactions in Neon  

Microsoft Academic Search

The production of hadrons in charged-current (anti)neutrino interactions is studied with the bubble chamber BEBC exposed ot the CERN (anti)neutrino wide-band beam. Fast-hadron production in a neon target is found to be attennuated as compared to that in a hydrogen target. This feature is discussed within the theoretical models based on the idea of a hadron formation length. The experimental

T. Coghen; J. Czyzewski; W. Wittek; Michael Aderholz; J. Guy; G. T. Jones; U. F. Katz; P. Marage; Douglas Robert Ogston Morrison; Gerald Myatt; N. Schmitz; W A Venus

1996-01-01

458

Neon and xenon isotopes in MORB: implications for the earth-atmosphere evolution  

Microsoft Academic Search

The isotopic composition of neon and xenon measured in MORB glasses confirm significant deviations from atmospheric values. These are (1) 21Ne excesses which are attributed to nucleogenic reactions in the mantle: (2) 20Ne\\/22Ne ratios higher than the air ratio interpreted as an evidence for the occurrence of solar-type Ne at depth: (3) 129Xe and 131-136Xe excesses, attributed to both extinct

Bernard Marty

1989-01-01

459

Predicting helium and neon adsorption and separation on carbon nanotubes by Monte Carlo simulation  

Microsoft Academic Search

The adsorption of helium and neon mixtures on single-walled carbon nanotubes (SWCNTs) was investigated at various temperatures\\u000a (subcritical and supercritical) and pressures using canonical Monte Carlo (CMC) simulation. Adsorption isotherms were obtained\\u000a at different temperatures (4, 40, 77 and 130 K) and pressures ranging from 1 to 16 MPa. Separation factors and isosteric enthalpies\\u000a of adsorption were also calculated. Moreover, the adsorption

Zabiollah Bolboli Nojini; Amir Abbas Rafati; Seyed Majid Hashemianzadeh; Sepideh Samiee

2011-01-01

460

X-ray diffraction and equation of state of solid neon to 110 GPa  

Microsoft Academic Search

Solid neon was compressed under static conditions at 300 K to pressures in the 100 GPa (megabar) range using diamond-anvil cell techniques. The crystal structure and \\/ital P\\/-\\/ital V\\/ equation of state were determined by energy-dispersive x-ray diffraction with microcollimated synchrotron radiation. Pressures were determined from ruby fluorescence spectra and from x-ray diffraction of tungsten powder contained within the sample.

R. J. Hemley; C. S. Zha; A. P. Jephcoat; H. K. Mao; L. W. Finger; D. E. Cox

1989-01-01

461

Helium-neon laser irradiation inhibits the growth of kidney epithelial cells in culture  

Microsoft Academic Search

We have investigated the in vitro action of helium-neon (He-Ne) laser light on the cell cycle and the growth of rat kidney epithelial cell cultures. Dose-response studies showed that repeated He-Ne irradiation (dose rate 40 mW\\/cm2) once a day in a dose range between 11.9 and 142 J\\/cm2 significantly inhibited cell growth, while daily irradiation with 4.7 J\\/cm2 had no

Andreas J. Gross; Wolfgang Jelkmann

1990-01-01

462

Drift Velocities of Slow Electrons in Helium, Neon, Argon, Hydrogen, and Nitrogen  

Microsoft Academic Search

The drift velocities of electrons in helium, neon, argon, hydrogen, and nitrogen have been measured for Ep values between 10-4 and 10 volt\\/cm-mm Hg at temperatures between 77°K and 373°K. The data were obtained from measurements of electron transit time in an improved version of the double-shutter tube developed by Bradbury and Nielsen. By applying sufficiently small voltage pulses to

J. L. Pack; A. V. Phelps

1961-01-01

463

Metastable and charged particle decay in neon afterglow studied by the breakdown time delay measurements  

SciTech Connect

Memory effect--the long time variation of the electrical breakdown time delay on the relaxation time t{sub d}({tau}) in neon--was explained by the Ne({sup 3}P{sub 2}) (1s{sub 5}) metastable state remaining from the preceding glow [Dj. A. Bosan, M. K. Radovic, and Dj. M. Krmpotic, J. Phys. D 19, 2343 (1986)]. However, the authors neglected the quenching processes that reduce the effective lifetime of metastable states several orders of magnitude below that of the memory effect observations. In this paper the time delay measurements were carried out in neon at the pressure of 6.6 mbar in a gas tube with gold-plated copper cathode, and the approximate and exact numerical models are developed in order to study the metastable and charged particle decay in afterglow. It was found that the metastable hypothesis completely failed to explain the afterglow kinetics, which is governed by the decay of molecular neon ions and molecular nitrogen ions produced in Ne{sub 2}{sup +} collisions with nitrogen impurities; i.e., Ne{sub 2}{sup +}+N{sub 2}{yields}N{sub 2}{sup +}+2Ne. Charged particle decay is followed up to hundreds of milliseconds in afterglow, from ambipolar to the free diffusion limit. After that, the late afterglow kinetics in neon can be explained by the nitrogen atoms recombining on the cathode surface and providing secondary electrons that determine the breakdown time delay down to the cosmic rays and natural radioactivity level.

Markovic, V. Lj.; Gocic, S. R.; Stamenkovic, S. N.; Petrovic, Z. Lj. [Department of Physics, University of Nis, P.O. Box 224, 18001 Nis (Serbia); Institute of Physics, P.O. Box 68, 11000 Belgrade (Serbia and Montenegro)

2007-10-15

464

Numerical model of an ac plasma display panel cell in neon-xenon mixtures  

Microsoft Academic Search

We present a self-consistent 1D model of the discharge initiated in an ac plasma display panel cell. The model is based on a two-moments fluid description of electron and ion transport, coupled with Poisson’s equation, and with a set of kinetic equations characterizing the evolution of the population of excited states leading to UV emission in neon-xenon mixtures. Results are

J. Meunier; Ph. Belenguer; J. P. Boeuf

1995-01-01

465

Low-Energy Helium-Neon Laser Irradiation Increases the Motility of Cultured Human Keratinocytes  

Microsoft Academic Search

Helium-neon (HeNe) laser irradiation is known to stimulate wound healing. We investigated whether the biostimulatory effects of HeNe irradiation result from enhancement of keratinocyte proliferation or motility. HeNe effects on keratinocyte motility were evaluated by irradiating a “wounded” culture with 0.8 J\\/cm2 3 times over a 20-h period. At 20 h post-irradiation, videocinemicroscopy and sequential quantitative measurements of the leading

Ann F. Haas; R. Rivkah Isseroff; Ronald G. Wheeland; Pamela A. Rood; Phillip J. Graves

1990-01-01

466

Isotopic composition of solar wind neon measured by CELIAS\\/MTOF on board SOHO  

Microsoft Academic Search

We present first results taken from the high-resolution mass time-of-flight spectrometer (MTOF) of the charge, element, and isotope analysis system (CELIAS) experiment on board the Solar and Heliospheric Observatory (SOHO) spacecraft launched in December 1995, concerning the abundance ratios of neon isotopes in the solar wind. We obtain the isotopic ratios 20Ne\\/22Ne=(13.8+\\/-0.7) and 20Ne\\/21Ne=(440+\\/-110), which agree with the values obtained

R. Kallenbach; F. M. Ipavich; P. Bochsler; S. Hefti; D. Hovestadt; H. Grünwaldt; M. Hilchenbach; W. I. Axford; H. Balsiger; A. Bürgi; M. A. Coplan; A. B. Galvin; J. Geiss; F. Gliem; G. Gloeckler; K. C. Hsieh; B. Klecker; M. A. Lee; S. Livi; G. G. Managadze; E. Marsch; E. Möbius; M. Neugebauer; K.-U. Reiche; M. Scholer; M. I. Verigin; B. Wilken; P. Wurz

1997-01-01

467

Effect of Helium-Neon Laser Irradiation on Hair Follicle Growth Cycle of Swiss Albino Mice  

Microsoft Academic Search

We report the results of a study carried out to investigate the effect of helium-neon (He-Ne) laser (632.8 nm) irradiation on the hair follicle growth cycle of testosterone-treated and untreated mice. Both histology and optical coherence tomography (OCT) were used for the measurement of hair follicle length and the relative percentage of hair follicles in different growth phases. A positive

S. Shukla; K. Sahu; Y. Verma; K. D. Rao; A. Dube; P. K. Gupta

2010-01-01

468

University of Virginia Physical Science SOL Activities: Neon Bulbs & Motion of Charge  

NSDL National Science Digital Library

This item is a lesson plan featuring the neon bulb, an object that can be lighted either by electric current or by static charge. Accompanied by detailed background information, this lesson promotes conceptual understanding of electron transfer. It includes printable data sheets for use in the physics classroom. No math is required. This lesson is part of a larger collection generated by the University of Virginia Department of Physics outreach program.

Morse, Robert

2006-11-07

469

Probabilities of double Auger processes upon the decay of the K-vacancy in neon  

Microsoft Academic Search

Probabilities of double Auger processes upon the decay of the K-vacancy in the neon atom are calculated. The final-state correlations of core electrons and correlations of core electrons with Auger electrons are found to be the principal contributors to the double Auger processes. Calculated total probability of double Auger processes upon the decay of the K-vacancy in Ne is 5.39%

A. G. Kochur; V. L. Sukhorukov; V. F. Demekhin

2004-01-01

470

Population genetic structure of the neon damselfish ( Pomacentrus coelestis ) in the northwestern Pacific Ocean  

Microsoft Academic Search

The population genetic structure of the neon damselfish (Pomacentrus coelestis) in the northwestern Pacific Ocean was revealed by the hypervariable control region of the mitochondrial gene (343 bp). In\\u000a total, 170 individuals were sampled from 8 localities distributed between Taiwan and Japan, and 71 haplotypes were obtained\\u000a through sequence alignment. High haplotype diversity (h = 0.956 ± 0.008) with low nucleotide diversity (? = 0.010 ± 0.006) was observed,

Shang-Yin V. Liu; Tomoyuki Kokita; Chang-Feng Dai

2008-01-01

471

PRESOLAR GRAINS FROM NOVAE: EVIDENCE FROM NEON AND HELIUM ISOTOPES IN COMET DUST COLLECTIONS  

SciTech Connect

Presolar grains in meteorites and interplanetary dust particles carry non-solar isotopic signatures pointing to origins in supernovae, giant stars, and possibly other stellar sources. There have been suggestions that some of these grains condensed in the ejecta of classical nova outbursts, but the evidence is ambiguous. We report neon and helium compositions in particles captured on stratospheric collectors flown to sample materials from comets 26P/Grigg-Skjellerup and 55P/Tempel-Tuttle that point to condensation of their gas carriers in the ejecta of a neon (ONe) nova. The absence of detectable {sup 3}He in these particles indicates space exposure to solar wind irradiation of a few decades at most, consistent with origins in cometary dust streams. Measured {sup 4}He/{sup 20}Ne, {sup 20}Ne/{sup 22}Ne, {sup 21}Ne/{sup 22}Ne, and {sup 20}Ne/{sup 21}Ne isotope ratios, and a low upper limit on {sup 3}He/{sup 4}He, are in accord with calculations of nucleosynthesis in neon nova outbursts. Of these, the uniquely low {sup 4}He/{sup 20}Ne and high {sup 20}Ne/{sup 22}Ne ratios are the most diagnostic, reflecting the large predicted {sup 20}Ne abundances in the ejecta of such novae. The correspondence of measured Ne and He compositions in cometary matter with theoretical predictions is evidence for the presence of presolar grains from novae in the early solar system.

Pepin, Robert O.; Palma, Russell L. [Department of Physics, University of Minnesota, Minneapolis, MN 55455 (United States); Gehrz, Robert D. [Department of Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Starrfield, Sumner, E-mail: pepin001@umn.edu [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States)

2011-12-01

472