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1

Testing and evaluation of thermal cameras for absolute temperature measurement  

Microsoft Academic Search

The accuracy of temperature measurement is the most important criterion for the evaluation of thermal cameras used in applications requiring absolute temperature measurement. All the main international metrological organizations currently propose a parameter called uncertainty as a measure of measurement accuracy. We propose a set of parameters for the characterization of thermal measurement cameras. It is shown that if these

Krzysztof Chrzanowski; Joachim Fischer; Robert Matyszkiel

2000-01-01

2

Absolute thermal lens method to determine fluorescence quantum efficiency and concentration quenching of solids  

Microsoft Academic Search

An absolute thermal lens method to determine fluorescence quantum efficiency and concentration quenching of solids is described in this work. The quantum efficiency of low silica calcium aluminate glasses doped with different concentrations of neodymium dioxide and melted under vacuum conditions to remove water has been measured by using mode-mismatched thermal lens spectrometry. It has been shown that the thermal

M. L. Baesso; A. C. Bento; A. A. Andrade; J. A. Sampaio; E. Pecoraro; L. A. O. Nunes; T. Catunda; S. Gama

1998-01-01

3

Nonlinear effects in thermal wave propagation near zero absolute temperature  

Microsoft Academic Search

The nonlinear theory of thermal wave propagation at low temperatures, i.e. in the realm of hyperbolic heat conduction, is discussed with regard to implications of experimental data and numerical calculations. Simplifying assumptions of earlier approaches are replaced by a consequent nonlinear thermodynamics. The effects of nonlinearity on the solution behavior are investigated. In particular, Lax conditions on shock waves are

Vito Antonio Cimmelli; Kurt Frischmuth

2005-01-01

4

Absolute salt dynamics from excess maturity and thermal anomalies  

Microsoft Academic Search

In the Danish North Sea area hydrocarbon occurrences are often related to salt structures. Assessment of the dynamic evolution of salt structures and possible related hydrocarbon traps is therefore important in order to predict the potential of a given structure. A new method for assessing the time of onset of diapirism and salt flow-speed from inversion of thermal indicators and

R. O. Thomsen; J. A. Korstgard; I. Lerche

1991-01-01

5

A Simple Relation Between Thermal Conductivity, Specific Heat and Absolute Temperature  

Microsoft Academic Search

A relation of the form kaC=K1T+K2, between thermal conductivity k, atomic heat (aC), and absolute temperature T, is shown to hold for zinc, sodium, lithium, copper, lead, aluminum and mercury. The possibility is indicated of an equation of this sort based on the assumption of a double mechanism of heat conduction-an atomic lattice along which energy is transmitted as elastic

C. C. Bidwell

1928-01-01

6

Absolute thermal fission yields for ²³⁵U  

Microsoft Academic Search

Absolute ²³⁵U thermal fission yields are given for the stable and long-lived isotopes of krypton, rubidium, strontium, zirconium, molybdenum, ruthenium, xenon, cesium, barium, lanthanum, cerium, neodymium, and samarium. The principal measurement technique for the fission product isotopes was isotope-dilution mass spectrometry. The number of fissions was established by summing the number of fission product atoms in the heavy mass peak.

W. J. Maeck; W. A. Emel; F. A. Duce; R. L. Tromp; J. W. Meteer

1978-01-01

7

ELECTROMOTIVE FORCE, EMF (CELLS)  

SciTech Connect

The voltage or electric potential difference across the terminals of a cell when no current is drawn from it. The emf of a cell is the sum of the electric potential differences (PDs) produced by a separation of charges (electrons or ions) that can occur at each phase boundary (or interface) in the cell. The magnitude of each PD depends on the chemical nature of the two contacting phases. Thus, at the interface between two different metals, some electrons will have moved from the metal with a higher free energy of electrons to the metal with a lower free energy of electrons. The resultant charge separation will produce a PD (just as charge separation produces a voltage across a capacitor) that, at equilibrium, exactly opposes further electron flow. Similarly, PDs can be produced when electrons partition across a metal/solution interface or metal/solid interface, and when ions partition across a solution/membrane/solution interface.

Archer, M.D.; Feldberg, S.W.

1998-09-16

8

Photo Induced-EMF Sensor Shield.  

National Technical Information Service (NTIS)

A photo-EMF detector including a shield to prevent a portion of the detector from illumination. The shield prevents the generation of unwanted noise-currents, thus increasing the performance of the photo-EMF detector.

G. J. Dunning M. Sokolich D. Vogel D. M. Pepper

2004-01-01

9

EMF and the public health  

SciTech Connect

The availability of reasonably priced electric power underpins the American standard of living, the nation`s industrial strength, and even our creature comforts. Utility experts estimate that by the end of this century electric utility infrastructure such as transmission lines, distribution lines, substations, and the like will expand by as much as 15 percent to serve increased customer demands for power. The electric utility industry today, however, is faced with an unanticipated consequence of its own success as health questions have been raised regarding electric and magnetic fields (EMF or EMR). These fields are created whenever electric current passes through power lines or electrical equipment. While people are exposed to EMF from electrical appliances, household wiring, and even household water pipes to which the home electrical system has been grounded, most of the attention has centered on high-voltage transmission lines and, to a lesser extent, neighborhood distribution lines. The scientific debate has been fueled by epidemiological studies. Epidemiology, which is the study of the distribution of diseases in the human population, is useful in identifying statistical associations that may reflect a causal relationship between an exposure and a disease. Some EMF epidemiological studies have reported positive statistical associations between residential and occupational exposures to EMF and certain childhood and adult cancers, including leukemia, brain cancer, lymphoma, and breast cancer. While scientists debate the meaning of these studies and conduct further studies, the debate is now moving into America`s courtrooms as private litigants seek compensation for physical harm and damage to property values.

Krieger, R.W. [Krieger & Associates, Washington, DC (United States); Withey, M.E. [Shroeter, Goldmark & Bender, Seattle, WA (United States)

1994-12-31

10

EMF Responses in Farm Animals  

SciTech Connect

Relatively few studies have been performed investigating the effects of EMF exposure on farm animals. Most of those that have been described in the literature are of surveys of animals living in the vicinity of power transmission lines. Even fewer studies have been conducted in large animals under controlled laboratory conditions. Results generally provide little evidence that electric and/or magnetic fields at environmental levels (under transmission lines up to 1000 kV) affect farm animals. There is limited evidence that cows exposed to EMF may exhibit slight changes in length of estrous cycle, although associated hormones (eg. progesterone) appear to be unaffected. The effects of electric fields on development in swine (some increase in birth defects and malformations) exposed to high strength electric fields were not consistent across generations nor supported by comparable rodent studies. Finally, electrical currents and"stray voltages", parameters associated with EMF, are found on some farms above perception levels. These voltages and currents can produce behavioral changes in farm animals and may impact production or health of the animals.

Anderson, Larry E. (BATTELLE (PACIFIC NW LAB)); R Matthes, JH Bernhardt, and MH Repacholi

1999-10-19

11

Containing the costs of the EMF problem  

SciTech Connect

The uncertainty surrounding possible health effects of power-frequency electric and magnetic fields (EMF's) is fueling a costly controversy over the safety of high voltage transmission lines, neighborhood power-distribution circuits, home and office wiring, elelctrical appliances, and office equipment. Mounting public concerns are driven primarily by a number of epidemiological studies that show increased risks of cancer among populations thought to experience unusual patterns of EMF exposure. Because the scientific evidence on EMF bioeffects is both complicated and contradictory, regulatory bodies and scientific standard-setting organizations have been unable to reach consensus on prescriptive approaches to EMF risk management. Although scientific opinion varies widely about whether the EMF-cancer connection is real, public apprehension over potential EMF hazards has prompted a host of political, legal, and market reactions.

Florig, H.K. (Resources for the Future, Washington, DC (United States))

1992-07-24

12

Absolute magnitudes of asteroids and a revision of asteroid albedo estimates from WISE thermal observations  

NASA Astrophysics Data System (ADS)

We obtained estimates of the Johnson V absolute magnitudes (H) and slope parameters (G) for 583 main-belt and near-Earth asteroids observed at Ond?ejov and Table Mountain Observatory from 1978 to 2011. Uncertainties of the absolute magnitudes in our sample are <0.21 mag, with a median value of 0.10 mag. We compared the H data with absolute magnitude values given in the MPCORB, Pisa AstDyS and JPL Horizons orbit catalogs. We found that while the catalog absolute magnitudes for large asteroids are relatively good on average, showing only little biases smaller than 0.1 mag, there is a systematic offset of the catalog values for smaller asteroids that becomes prominent in a range of H greater than 10 and is particularly big above H 12. The mean (Hcatalog - H) value is negative, i.e., the catalog H values are systematically too bright. This systematic negative offset of the catalog values reaches a maximum around H = 14 where the mean (Hcatalog - H) is -0.4 to -0.5. We found also smaller correlations of the offset of the catalog H values with taxonomic types and with lightcurve amplitude, up to 0.1 mag or less. We discuss a few possible observational causes for the observed correlations, but the reason for the large bias of the catalog absolute magnitudes peaking around H = 14 is unknown; we suspect that the problem lies in the magnitude estimates reported by asteroid surveys. With our photometric H and G data, we revised the preliminary WISE albedo estimates made by Masiero et al. (Masired, J.R. et al. [2011]. Astrophys. J. 741, 68-89) and Mainzer et al. (Mainzer, A. et al. [2011b]. Astrophys. J. 743, 156-172) for asteroids in our sample. We found that the mean geometric albedo of Tholen/Bus/DeMeo C/G/B/F/P/D types with sizes of 25-300 km is pV = 0.057 with the standard deviation (dispersion) of the sample of 0.013 and the mean albedo of S/A/L types with sizes 0.6-200 km is 0.197 with the standard deviation of the sample of 0.051. The standard errors of the mean albedos are 0.002 and 0.006, respectively; systematic observational or modeling errors can predominate over the quoted formal errors. There is apparent only a small, marginally significant difference of 0.031 0.011 between the mean albedos of sub-samples of large and small (divided at diameter 25 km) S/A/L asteroids, with the smaller ones having a higher albedo. The difference will have to be confirmed and explained; we speculate that it may be either a real size dependence of surface properties of S type asteroids or a small size-dependent bias in the data (e.g., a bias towards higher albedos in the optically-selected sample of asteroids). A trend of the mean of the preliminary WISE albedo estimates increasing with asteroid size decreasing from D 30 down to 5 km (for S types) showed in Mainzer et al. (Mainzer, A. et al. [2011a]. Astrophys. J. 741, 90-114) appears to be mainly due to the systematic bias in the MPCORB absolute magnitudes that progressively increases with H in the corresponding range H = 10-14.

Pravec, Petr; Harris, Alan W.; Kunirk, Peter; Gald, Adrin; Hornoch, Kamil

2012-09-01

13

A Simple Demonstration of Back emf  

ERIC Educational Resources Information Center

|In discussing motors, one college textbook says, "As the coil (of a motor) rotates in a magnetic field, a back emf is generated that tends to counter the emf that supplies the current." This is a true statement, but it does little to enhance student understanding of how and why it is created. In this paper, I will explain how to take students

Turner, Lou

2009-01-01

14

A Simple Demonstration of Back emf  

ERIC Educational Resources Information Center

In discussing motors, one college textbook says, "As the coil (of a motor) rotates in a magnetic field, a back emf is generated that tends to counter the emf that supplies the current." This is a true statement, but it does little to enhance student understanding of how and why it is created. In this paper, I will explain how to take students step

Turner, Lou

2009-01-01

15

Securing insurance coverage for EMF claims  

SciTech Connect

When confronted with lawsuits resulting from EMF-related claims, utilities must aggressively work to ensure that they receive the full protection and defense due them by their insurance companies. Within the last two years, electric utilities have been increasingly subject to claims alleging that plaintiffs have suffered bodily injury as a result of exposure to electromagnetic fields (EMF) and that this exposure has caused everything from emotional distress to cancer. The plaintiffs generally claim that EMF exposure has also caused property damage - usually in the fourth of a reduction in the value of their residence. Claims have also been made on the grounds that EMF constitutes a tresspass and nuisance, which has prevented plaintiffs from using their property to the fullest extent. While utilities may debate the degree of harm, if any, caused by exposure to EMF, one thing is certain: The current EMF claims are only the tip of the iceberg and are not likely to dissipate any time soon. As a result, utilities must example their insurance coverage to determine whether any existing or future EMF claims are covered under the company's policies. Such insurance would most likely help pay for the cost of defending against EMF lawsuits and indemnify the company if any liability is assessed.

Meyer, K.A. (Paul, Hatings, Janofsky Walker, Los Angeles, CA (United States))

1992-02-15

16

The absolute chronology and thermal processing of solids in the solar protoplanetary disk.  

PubMed

Transient heating events that formed calcium-aluminum-rich inclusions (CAIs) and chondrules are fundamental processes in the evolution of the solar protoplanetary disk, but their chronology is not understood. Using U-corrected Pb-Pb dating, we determined absolute ages of individual CAIs and chondrules from primitive meteorites. CAIs define a brief formation interval corresponding to an age of 4567.30 0.16 million years (My), whereas chondrule ages range from 4567.32 0.42 to 4564.71 0.30 My. These data refute the long-held view of an age gap between CAIs and chondrules and, instead, indicate that chondrule formation started contemporaneously with CAIs and lasted ~3 My. This time scale is similar to disk lifetimes inferred from astronomical observations, suggesting that the formation of CAIs and chondrules reflects a process intrinsically linked to the secular evolution of accretionary disks. PMID:23118187

Connelly, James N; Bizzarro, Martin; Krot, Alexander N; Nordlund, ke; Wielandt, Daniel; Ivanova, Marina A

2012-11-01

17

LVI. The thermal conductivity of potassium chrome alum at temperatures below one degree absolute  

Microsoft Academic Search

An account is given of measurements of the thermal conductivity of potassium chrome alum made between 014 and 030 K., from which it is concluded that the mean free path of the phonons in the crystal is about 1\\/2 mm. In the method employed, a long single crystal of the salt, isolated from the outside world, is demagnetized to a

C. G. B. Garett

1950-01-01

18

High-Throughput Omics Technologies: Potential Tools for the Investigation of Influences of EMF on Biological Systems  

PubMed Central

The mode of action of a huge amount of agents on biological systems is still unknown. One example where more questions than answers exist is covered by the term electromagnetic fields (EMF). Use of wireless communication, e.g. mobile phones, has been escalated in the last few years. Due to this fact, a lot of discussions dealt with health consequences of EMF emitted by these devices and led to an increased investigation of their effects to biological systems, mainly by using traditional methods. Omics technologies have the advantage to contain methods for investigations on DNA-, RNA- and protein level as well as changes in the metabolism. This literature survey is an overview of the available scientific publications regarding biological and health effects of EMF and the application of new high-throughput technologies. The aim of the study was to analyse the amount and the distribution of these technologies and to evaluate their relevance to the risk analysis of EMF. At present, only transcriptomics is able to analyse almost all of the specific molecules. In comparison to ionising radiation, fewer articles dealt with health effects of EMF. Interestingly, most of the EMF articles came from European institutions. Although omics techniques allow exact and simultaneous examinations of thousands of genes, proteins and metabolites in high-throughput technologies, it will be an absolute prerequisite to use standardised protocols and to independently validate the results for comparability and eventually for sound standing statements concerning possible effects of agents like EMF on biological systems.

Blankenburg, M; Haberland, L; Elvers, H.-D; Tannert, C; Jandrig, B

2009-01-01

19

Autism and EMF? Plausibility of a pathophysiological link - Part I.  

PubMed

Although autism spectrum conditions (ASCs) are defined behaviorally, they also involve multileveled disturbances of underlying biology that find striking parallels in the physiological impacts of electromagnetic frequency and radiofrequency exposures (EMF/RFR). Part I of this paper will review the critical contributions pathophysiology may make to the etiology, pathogenesis and ongoing generation of core features of ASCs. We will review pathophysiological damage to core cellular processes that are associated both with ASCs and with biological effects of EMF/RFR exposures that contribute to chronically disrupted homeostasis. Many studies of people with ASCs have identified oxidative stress and evidence of free radical damage, cellular stress proteins, and deficiencies of antioxidants such as glutathione. Elevated intracellular calcium in ASCs may be due to genetics or may be downstream of inflammation or environmental exposures. Cell membrane lipids may be peroxidized, mitochondria may be dysfunctional, and various kinds of immune system disturbances are common. Brain oxidative stress and inflammation as well as measures consistent with blood-brain barrier and brain perfusion compromise have been documented. Part II of this paper will review how behaviors in ASCs may emerge from alterations of electrophysiological oscillatory synchronization, how EMF/RFR could contribute to these by de-tuning the organism, and policy implications of these vulnerabilities. Changes in brain and autonomic nervous system electrophysiological function and sensory processing predominate, seizures are common, and sleep disruption is close to universal. All of these phenomena also occur with EMF/RFR exposure that can add to system overload ('allostatic load') in ASCs by increasing risk, and worsening challenging biological problems and symptoms; conversely, reducing exposure might ameliorate symptoms of ASCs by reducing obstruction of physiological repair. Various vital but vulnerable mechanisms such as calcium channels may be disrupted by environmental agents, various genes associated with autism or the interaction of both. With dramatic increases in reported ASCs that are coincident in time with the deployment of wireless technologies, we need aggressive investigation of potential ASC - EMF/RFR links. The evidence is sufficient to warrant new public exposure standards benchmarked to low-intensity (non-thermal) exposure levels now known to be biologically disruptive, and strong, interim precautionary practices are advocated. PMID:24095003

Herbert, Martha R; Sage, Cindy

2013-10-04

20

Autism and EMF? Plausibility of a pathophysiological link part II.  

PubMed

Autism spectrum conditions (ASCs) are defined behaviorally, but they also involve multileveled disturbances of underlying biology that find striking parallels in the physiological impacts of electromagnetic frequency and radiofrequency radiation exposures (EMF/RFR). Part I (Vol 776) of this paper reviewed the critical contributions pathophysiology may make to the etiology, pathogenesis and ongoing generation of behaviors currently defined as being core features of ASCs. We reviewed pathophysiological damage to core cellular processes that are associated both with ASCs and with biological effects of EMF/RFR exposures that contribute to chronically disrupted homeostasis. Many studies of people with ASCs have identified oxidative stress and evidence of free radical damage, cellular stress proteins, and deficiencies of antioxidants such as glutathione. Elevated intracellular calcium in ASCs may be due to genetics or may be downstream of inflammation or environmental exposures. Cell membrane lipids may be peroxidized, mitochondria may be dysfunctional, and various kinds of immune system disturbances are common. Brain oxidative stress and inflammation as well as measures consistent with blood-brain barrier and brain perfusion compromise have been documented. Part II of this paper documents how behaviors in ASCs may emerge from alterations of electrophysiological oscillatory synchronization, how EMF/RFR could contribute to these by de-tuning the organism, and policy implications of these vulnerabilities. It details evidence for mitochondrial dysfunction, immune system dysregulation, neuroinflammation and brain blood flow alterations, altered electrophysiology, disruption of electromagnetic signaling, synchrony, and sensory processing, de-tuning of the brain and organism, with autistic behaviors as emergent properties emanating from this pathophysiology. Changes in brain and autonomic nervous system electrophysiological function and sensory processing predominate, seizures are common, and sleep disruption is close to universal. All of these phenomena also occur with EMF/RFR exposure that can add to system overload ('allostatic load') in ASCs by increasing risk, and can worsen challenging biological problems and symptoms; conversely, reducing exposure might ameliorate symptoms of ASCs by reducing obstruction of physiological repair. Various vital but vulnerable mechanisms such as calcium channels may be disrupted by environmental agents, various genes associated with autism or the interaction of both. With dramatic increases in reported ASCs that are coincident in time with the deployment of wireless technologies, we need aggressive investigation of potential ASC-EMF/RFR links. The evidence is sufficient to warrant new public exposure standards benchmarked to low-intensity (non-thermal) exposure levels now known to be biologically disruptive, and strong, interim precautionary practices are advocated. PMID:24113318

Herbert, Martha R; Sage, Cindy

2013-10-08

21

Absolute Zero  

Microsoft Academic Search

Absolute Zero is a two hour PBS special attempting to bring to the general public some of the advances made in 400 years of thermodynamics. It is based on the book ``Absolute Zero and the Conquest of Cold'' by Tom Shachtman. Absolute Zero will call long-overdue attention to the remarkable strides that have been made in low-temperature physics, a field

Russell J. Donnelly; D. Sheibley; M. Belloni; D. Stamper-Kurn; W. F. Vinen

2006-01-01

22

Latest on the absolute age of the Paleocene-Eocene Thermal Maximum (PETM): New insights from exact stratigraphic position of key ash layers + 19 and - 17  

NASA Astrophysics Data System (ADS)

We constructed a precise early Eocene orbital cyclostratigraphy for DSDP Site 550 (Leg 80, Goban Spur, North Atlantic) utilizing precession related cycles as represented in a high-resolution X-ray fluorescence based barium core log. Based on counting of those cycles, we constrain the exact timing of two volcanic ash layers in Site 550 which correlate to ashes + 19 and - 17 of the Fur Formation in Denmark. The ashes, relative to the onset of the Paleocene-Eocene Thermal Maximum (PETM), are offset by 862 kyr and 672 kyr, respectively. When combined with published absolute ages for ash - 17, the absolute age for the onset of the PETM is consistent with astronomically calibrated ages. Using the current absolute age of 28.02 Ma for the Fish Canyon Tuff (FCT) standard for calibrating the absolute age of ash - 17 is consistent with tuning option 2 in the astronomically calibrated Paleocene time scale of Westerhold et al. (2008) [Westerhold, T., Rhl, U., Raffi, I., Fornaciari, E., Monechi, S., Reale, V., Bowles, J., and Evans, H.F., 2008, Astronomical calibration of the Paleocene time: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 257, p. 377-403]. Using the recently recalibrated absolute age of 28.201 Ma for the FCT standard is consistent with tuning option 3 in the astronomically calibrated Paleocene time scale. The new results do not support the existence of any additional 405-kyr cycle in the early Paleocene astronomically tuned time scale.

Westerhold, Thomas; Rhl, Ursula; McCarren, Heather K.; Zachos, James C.

2009-10-01

23

An Improved Application of the Transient Hot-Wire Technique for the Absolute Accurate Measurement of the Thermal Conductivity of Pyroceram 9606 up to 420 K  

NASA Astrophysics Data System (ADS)

This article describes the final refinements of a novel application of the transient hot-wire technique developed for the absolute, accurate measurements of the thermal conductivity of solids. Although the technique was originally developed five years ago, these new refinements allow a full understanding of the method and hence the performance of measurements with an absolute uncertainty of less than 1 %. New measurements of Pyroceram 9606 up to 420 K are reported. The maximum deviation of the present measurements is 0.54 %, while their standard deviation at the 95 % confidence level is 0.25 %. Since May 2007, Pyroceram 9606 is a European Commission certified thermal-conductivity reference material, designated as BCR-724, with an uncertainty of 6.5 % at the 95 % confidence level.

Assael, M. J.; Antoniadis, K. D.; Kakosimos, K. E.; Metaxa, I. N.

2008-04-01

24

EMF Genes Maintain Vegetative Development by Repressing the Flower Program in Arabidopsis  

Microsoft Academic Search

The EMBRYONIC FLOWER ( EMF ) genes EMF1 and EMF2 are required to maintain vegetative development and repress flower development. EMF1 encodes a putative transcriptional regulator, and EMF2 encodes a Polycomb group protein ho- molog. We examined expression profiles of emf mutants using GeneChip technology. The high degree of overlap in expres- sion changes from the wild type among the

Yong-Hwan Moon; Lingjing Chen; Hur-Song Chang; Tong Zhu; Daniel M. Maffeo; Z. Renee Sung

2003-01-01

25

Analysis of the induced EMF in permanent magnet brushless motors  

Microsoft Academic Search

The performance of permanent magnet brushless DC motors depends on their winding and magnetic designs. The conductor distribution and flux density distribution profiles determine the shape of induced EMF waveform. The shape of the induced EMF of the machine can be used to predict its torque performance. This paper presents a new method to analyze the induced EMF of the

Tahir Izhar; Arif Malik

2008-01-01

26

Health risk assessment in occupational EMF exposure  

Microsoft Academic Search

In our study we tried to evaluate the health estate of physiotherapists in relationship with occupational exposure. EMF measurements were made in workplaces, we applied special questionnaires, performed micronucleus test from lymfocytes, and urinary thioethers assay. The results were compared to those of a control group by statistical analytical methods like logistic regression. We found an overexposure of this profession

D. C. Dabala; Didi Surcel; Csaba Szanto

2009-01-01

27

Children's health and RF EMF exposure  

Microsoft Academic Search

The present report documents a dialogue between scientists reviewing the currently available scientific evidence with respect to the effects of RF EMF exposure on children. The focus was directed towards a transparent and comprehensible characterization of the findings and conclusions for the evaluation of the relationship between mobile phone communication and childrens health. The now available report, based on the

Peter Wiedemann; Holger Schutz; Franziska Borner; Gabriele Berg-Beckhoff; Rodney J Croft; Alexander Lerchl; Luc Martens; Georg Neubauer; Sabine Regel; Michael Repacholi

2009-01-01

28

Defending against EMF property devaluation cases  

SciTech Connect

Late last year, New York`s highest court, the Court of Appeals, ruled that the owner of property adjacent to a utility`s high-power electrical transmission lines could seek damages for a decrease in the market value of the property caused by the fear that the power lines might cause cancer, even if such a fear was not medically or scientifically reasonable. That decision has already begun to change the outlook on electromagnetic field (EMF) litigation for utilities.

Brandon, G. [Milbank, Tweed, Hadley & McCloy, New York, NY (United States)

1995-02-01

29

60 Hz EMF health effects-a scientific uncertainty  

Microsoft Academic Search

Extensive epidemiological and laboratory research has been conducted over the last 15 years on the biological and health consequences of exposure to ELF EMFs. Some epidemiological studies have found weak associations between exposure to power-frequency EMFs and some forms of cancer, such as leukemia; while other studies have failed to find such associations. The primary limitation with most epidemiological studies

Stephan P. Albert Bren

1995-01-01

30

Analysis of induced EMF in vibrating-sample magnetometers  

Microsoft Academic Search

The theoretical induced EMF for vibrating-sample magnetometers is derived. Assuming a point magnetic dipole sample, located in a general position with respect to a single-turn circular pickup coil, the instantaneous flux cutting the coil and the induced EMF due to sample motion are found to be linear combinations of elliptic integrals of the first and second kind. An alternative representation

E. E. Bragg; M. S. Seehra

1976-01-01

31

Absolute thermal expansion measurements of single-crystal silicon in the range 3001300 K with an interferometric dilatometer  

Microsoft Academic Search

The thermal expansion coefficient of single-crystal silicon has been measured in the range 3001300 K using an interferometric dilatometer. The measurement system consists of a double-path optical heterodyne interferometer and a radiant image furnace with a quartz vacuum tube, which provides both accuracy and rapidity of measurement. The uncertainties in length and temperature determination are within 4 nm and 0.4

M. Okaji

1988-01-01

32

Absolute thermal expansion measurements of single-crystal silicon in the range 300 1300 K with an interferometric dilatometer  

NASA Astrophysics Data System (ADS)

The thermal expansion coefficient of single-crystal silicon has been measured in the range 300 1300 K using an interferometric dilatometer. The measurement system consists of a double-path optical heterodyne interferometer and a radiant image furnace with a quartz vacuum tube, which provides both accuracy and rapidity of measurement. The uncertainties in length and temperature determination are within 4 nm and 0.4 K, respectively. A high-purity dislocation-free FZ silicon single crystal was used in the study. Thermal expansion coefficients of silicon oriented in the [111] direction have been determined over the temperature range from 300 to 1300 K. The standard deviation of the measurement data from the best fitting for the fifth-order polynomial in temperature is 2.110-8 K-1. The present value for the thermal expansion coefficient agrees within 910-8K-1 with the interferometric measurement of polycrystalline pure silicon by Roberts (1981) between 300 and 800 K and within 1.2 10-7 K-1 with the single-crystal X-ray diffractometric measurement by Okada and Tokumaru (1984) between 300 and 1300 K.

Okaji, M.

1988-11-01

33

Development of an EMF Measurements Database, EMF Rapid Program, Project #5, Interim Report: April 1995-December 1996  

SciTech Connect

The EMF measurement data sets in existence today were compiled with varying goals and techniques. Consequently, they have different information content as well as varying logical and physical structure. Future studies will continue to pursue varying goals and utilize techniques that cannot be known in advance. Primary goals for the EMF Measurements Database developed under the Department of Energy EMF RAPID Program are to develop a database structure that can accommodate the diversity of EMF data sets, provide guidance for production of future EMF data sets, and serve as an accessible repository of EMF measurement data. Specific objectives of the EMF Measurements Database are: o to preserve study descriptions, results and data; o to provide readily accessible, well-documented data; and o to facilitate communication among researchers. In addition, the EMF Measurements Database will encourage additional analysis of existing data sets, facilitate analysis of data from multiple projects, support design of new studies, and permit future issues in EMF exposure assessment to be addressed with existing data. Preservation of study descriptions and data is accomplished with a formal, but open, structure. Specifications have been developed for the various elements of the database. Each data set in the database is formally described by a metadata file. The structured metadata file describes the origin, development, logical and physical structure and distribution mechanism for each data set. The metadata for each data set is generated according to a specification developed for the EMF Measurements Database. The actual measurement data is contained in data Products for each data set. The number and type of data product will vary by data set. Most of the data products in the possession of the EMF Measurements Database are available for download from an Internet site. For some data sets, the data products will be maintained by other parties who may have their own access procedures. In addition, data set contributors or users can provide reports that describe results of the study and analysis of the data with text and figures. Guidelines have been developed for preparation of reports. Access to the EMF Measurements Database is provided via an Internet site (http://www.emf-data. erg). The site provides descriptive information in a home page, . . access to data products with a file transfer protocol (ftp) address, and links to other EMF-related sites.

T. Dan Bracken, Inc.

1997-04-01

34

EMF-cancer links: Yes, no, and maybe  

SciTech Connect

The controversy over whether or not low-level electromagnetic fields (EMF) can cause cancer has been smoldering for 15 years. This month it got a little hotter -- but there's still more smoke than fire. At the beginning of October, writer and EMF gadfly Paul Brodeur brought out his latest book exposing a purported EMF-cancer connection, entitled The Great Power-line Cover-up. Right on his heels, however, on 9 October, the British Medical Journal weighed in with two serious scientific assessments of the cancer risk. Unfortunately for those who long for a conclusive answer, one study found only a slight positive association between EMF and cancer, and the other found no link at all. Together the studies [open quotes]artfully provide middle-of-the-road type of evidence,[close quotes] says Dimitrios Trichopoulos, chairman of the epidemiology department at the Harvard School of Public Health.

Taubes, G.

1993-10-29

35

EMF in its infancy: A call for openness  

SciTech Connect

The author feels we are still in the awareness stage of EMF; the public is, for the most part, receptive to information and there is no real consus. He notes that it is this that shapes the approach of his company, PSI Energy, to public concerns about EMF: (1) when someone calls about EMF, they may just have heard about the subject; (2) someone concerned about EMF may or may not turn immediately to their local utility for information; and (3) PSI feels that, wherever a person turns, he or she should get good, factual information that permits an informed judgment. Those beliefs led directly to an important part of PSI's communications strategy: networking. Basically, networking is getting the information reprints, brochures, etc. - into the hands of the media, association's, state boards of health, etc. so that point (3) above can be handled for an anxious inquirer.

Norris, R.E.

1991-05-01

36

A novel line-to-line back EMF calculation for sensorless brushless DC motor drives  

Microsoft Academic Search

This paper proposes a novel line-to-line back EMF detection method for sensorless brushless DC (BLDC) motor drives. The actual phase back EMF signal can be indirectly obtained from the line-to-line back EMF. F function constructed based on line-to-line back EMF is calculated for commutation estimation. Compared to the traditional back EMF method, this scheme is simple to implement without the

Zicheng Li; Shanmei Cheng; Yi Qin; Kai Cai

2008-01-01

37

The design of Brushless DC motor Back-EMF control  

Microsoft Academic Search

The method of detecting the phase terminal voltages without current is to realize Back-EMF zero crossing. MC9S12XDP256 of dual CPU core completed the brushless DC motor. The function it possessed will completely achieve the task of controlling the Brushless DC motor. This paper discusses the theory of Back-EMF and the method of using S12X MCU to control Brushless DC motor

Xiong Hui; Xue YanBo

2010-01-01

38

Human health effects of EMFs: The cost of doing nothing  

NASA Astrophysics Data System (ADS)

Everyone is exposed to electromagnetic fields (EMFs) from electricity (extremely low frequency, ELF), communication frequencies and wireless devices (radiofrequency, RF), as well as naturally occurring EMFs. Concern of health hazards from EMFs has increased as the use of mobile phones and other wireless devices has grown in all segments of the population, especially children. While there has been strong evidence for an association between leukemia and residential or occupational exposure to ELF EMFs for many years, the standards in existence are not sufficiently stringent to protect from an increased risk of cancer. ELF EMFs also increase risk of at least two types of neurodegenerative diseases. For RF EMFs, standards are set at levels designed to avoid tissue heating, in spite of many reports of biological effects at intensities too low to cause significant heating. Recent evidence demonstrates elevations in risk of brain cancer and acoustic neuroma only on the side of the head where individuals used their mobile phone. Individuals who begin exposure at younger ages are more vulnerable. These data indicate that the existing standards for radiofrequency exposure are not adequate. While there are many unanswered questions, the cost of doing nothing may result in an increasing number of people, many of them young, developing these diseases.

Carpenter MD, David O.

2010-04-01

39

Measurements of linear thermal expansion coefficients of copper SRM 736 and some commercially available coppers in the temperature range 20300 K by means of an absolute interferometric dilatometer  

Microsoft Academic Search

The thermal expansivities of several grades of copper were measured in the temperature range 20300 K by means of an absolute laser interferometric dilatometer. The present results for copper standard reference material (NIST; SRM 736) and three commercially available kinds of copper, such as a high-purity copper (99.999% purity), an oxygen-free high-conductivity copper and a tough-pitch copper, show good agreement

M. Okaji; N. Yamada; H. Kato; K. Nara

1997-01-01

40

Review of Electromagnetic Frequency (EMF) Safety Program for Homestead ARB, FL.  

National Technical Information Service (NTIS)

A review of the electromagnetic frequency (EMF) safety program at Homestead ARB was conducted. Additionally, a survey of two previously unassessed emitters was performed. USAFSAM personnel identified and corrected deficiencies in the existing base EMF saf...

M. Ames S. Ortiz Z. Sulaiman

2012-01-01

41

Assessment of the Genotoxic Effects of High Peak-Power Pulsed Electromagnetic Fields (EMFs).  

National Technical Information Service (NTIS)

This report results from a contract tasking Russian Academy of Sciences as follows: Because of the widespread increase in man-made sources of electromagnetic fields (EMFs), including high peak-power pulsed EMF (HPPP EMF), it has become important to study ...

N. Chemeris

2003-01-01

42

Cascaded EMF and speed sliding mode observer for the nonsalient PMSM  

Microsoft Academic Search

The paper presents an EMF and speed estimator for the nonsalient permanent magnet synchronous motor (PMSM). The method uses two cascaded sliding mode (SM) observers and is realized using only the measured voltages and currents of the motor. A first SM observer estimates the EMFs of the machine in the stationary reference frame. These EMFs are passed as inputs to

Mihai Comanescu

2010-01-01

43

INVITED EDITORIAL: Do we know enough about EMF-induced health effects?  

Microsoft Academic Search

Responsible Officer, International EMF Project, World Health Organization, 1211 Geneva 27, Switzerland In this issue Dr Zenon Sienkiewicz summarises the biological effects of exposure to electromagnetic fields (EMF). He concludes that there are few established consequences of EMF exposure at levels normally encountered by members of the general public, and that any health risk from these fields is likely to

Michael H. Repacholi

1998-01-01

44

Contribution of the Boundary Layer EMF to Magnetospheric Substorms.  

National Technical Information Service (NTIS)

The magnetospheric substorm process has been discussed from two different standpoints; As a result of a directly driven process powered by the cross-tail electromotive force (EMF), or as a release of magnetic energy stored in the magnetospheric tail. Out ...

R. Lundin I. Sandahl J. Woch R. Elphinstone

1991-01-01

45

A precautionary tale: the British response to cell phone EMF  

Microsoft Academic Search

The UK led the campaign for precautionary responses to cell phone EMF. The experience which informed this approach was BSE, a disease that originated and had greatest impact in the UK. Unsurprisingly, British politicians have responded even more directly than the EU to the cell phone issue, seeking to prove that they have \\

Adam Burgess

2002-01-01

46

Teaching Absolute Value Meaningfully  

ERIC Educational Resources Information Center

|What is the meaning of absolute value? And why do teachers teach students how to solve absolute value equations? Absolute value is a concept introduced in first-year algebra and then reinforced in later courses. Various authors have suggested instructional methods for teaching absolute value to high school students (Wei 2005; Stallings-Roberts

Wade, Angela

2012-01-01

47

Absolute refractive indices and thermal coefficients of CaF2, SrF2, BaF2, and LiF near 157 nm.  

PubMed

We present high-accuracy measurements for wavelengths near 157 nm of the absolute index of refraction, the index dispersion, and the temperature dependence of the index for the ultraviolet optical materials with cubic symmetry: CaF2, SrF2, BaF2, and LiF. Accurate values of these quantities for these materials are needed for designs of the lens systems for F2 excimer-laser-based exposure tools for 157-nm photolithography. These tools are expected to use CaF2 as the primary optical material and possibly one of the others to correct for chromatic aberrations. These optical properties were measured by the minimum deviation method. Absolute refractive indices were obtained with an absolute accuracy of 5 x 10(-6) to 6 x 10(-6). PMID:12009162

Burnett, John H; Gupta, Rajeev; Griesmann, Ulf

2002-05-01

48

Determination of EMF influence on a human exposed to EMF - modeling and methodology.  

PubMed

(Full text is available at http://www.manu.edu.mk/prilozi). The wide use of electric energy in every segment of everyday living demands specific attention be paid to investigations connected with biological effects from the influence of electromagnetic fields on humans and the environment. Investigations connected with electromagnetic influence assessment on human health emphasize the influences of electromagnetic fields in a wide frequency range. Here, the interest in knowing the mechanisms of these interactions and ways of determining them is obvious. The parameters and quantities that describe such influence depend on the frequency of the electromagnetic field source that underlines the importance of their appropriate definition. Induced currents and charges as well as electric field distribution, or SAR, are quantities that represent this influence. Their determination is important for the formulation of norms and standards for human protection from exposure to electromagnetic fields. In this paper, a developed procedure for the determination of electric field distribution in the human body when exposed to EMF influence is presented. Several issues emerge in the course of this, such as finding representative parameters for problem description, modeling of the incident field source, which is obvious in various forms and in a wide frequency range, modeling of the human body, which is complex in geometric aspect and has a wide range of electric characteristics in its parts, developing an appropriate calculation methodology and a suitable presentation of the results. Modeling the incident field form and the human body are in direct correlation with the calculation method developed for determining the electric field distribution. Developed methodology enables the electric field in the humans to be determined, and other parameters such as SAR to be calculated. Having those values, we can discuss the biological effects on humans from such exposure. Key words: Electromagnetic field, electromagnetic influence, human model, induced electric field, SAR. PMID:21258285

Ololoska, L; Janev, Lj; Loskovska, S

2010-12-01

49

Absolute refractive indices and thermal coefficients of CaF2, SrF2, BaF2, and LiF near 157 nm  

Microsoft Academic Search

We present high-accuracy measurements for wavelengths near 157 nm of the absolute index of refraction, the index dispersion, and the temperature dependence of the index for the ultraviolet optical materials with cubic symmetry: CaF2, SrF2, BaF2, and LiF. Accurate values of these quantities for these materials are needed for designs of the lens systems for F2 excimer-laser-based exposure tools for

John H. Burnett; Rajeev Gupta; Ulf Griesmann

2002-01-01

50

Facilities for calibration of dc emf measures and voltmeters  

SciTech Connect

A set of instruments for reproduction and storage of the emf and dc voltage unit and for transferring it directly to the location where measuring instruments (MIs) are used with an accuracy of (3-5) {center_dot} 10{sup {minus}7}, developed at the {open_quotes}VNIIFTRI{close_quotes} Research and Production Association (RPA) is described. The metrological characteristics of the set are investigated.

Gumenyuk, V.S.; Karpov, O.V.; Kutovoi, V.D.; Sarandi, A.E.; Shakirzyanova, F.R.; Shulga, V.M.

1994-06-01

51

Low-level EMFs are transduced like other stimuli  

Microsoft Academic Search

The aims of this study were to test the theory that transduction of low-level electromagnetic fields (EMFs) is mediated like other stimuli, and to determine the false-negative rate of the method used to assess the occurrence of transduction (intra-subject comparison of stimulus and non-stimulus states (ICOS)). A light stimulus was chosen as a basis of comparison because light could be

Andrew A. Marino; Glenn B. Bell; Andrew Chesson

1996-01-01

52

Molten salt EMF cell measurements on UGa alloys  

Microsoft Academic Search

The Gibbs free energies of formation of UGa3, UGa2 and U2Ga3 were determined by using high temperature molten salt galvanic cell measurements. Three cells were assembled and EMFs were measured. The typical cell is as follows: U(s)\\/\\/UCl3inLiClKCl(eutectic)(l)\\/\\/UGa(twophasealloy), where pure uranium is used as one of the electrodes and the other electrode is a two phase UGa alloy. The two phase

B Prabhakara Reddy; R Kandan; K Nagarajan; P. R Vasudeva Rao

2001-01-01

53

Emf, maximum power and efficiency of fuel cells  

SciTech Connect

The ideal voltage of steady-flow fuel cells is usually expressed by Emf = [minus] [Delta]G[degree]/nF where [Delta]G[degree] is the Gibbs free energy of reaction'' for the oxidation of the fuel at the supposed temperature of operation of the cell. Furthermore, the ideal power of the cell is expressed as the product of the fuel flow rate with this emf. Such viewpoints are flawed in several respects. Even if the cell operates isothermally, the use of the conventional [Delta]G[degree] of reaction (a) assumes that the products of reaction leave separately from one another ( and from any unused fuel); and (b) when [Delta]S of reaction is positive, it assumes that a free heat source exists at the operating temperature, whereas if [Delta]S is negative, it neglects the potential power which theoretically could be obtained from the heat released during oxidation. Moreover, (c) the usual cell does not operate isothermally, but (virtually) adiabatically. Comment (a) is often accounted for by employing the Nernst equation to correct for the dilution of reactants and/or products. Nevertheless, comments (b) and (c) remain pertinent. Rather than with emf, the proper starting place is with power output. The ideal power is that which would be obtained if the fuel were oxidized without irreversible entropy generation. Among other factors, this ideal power output depends upon the ratio of oxidant to fuel flow rate (e.g., air-fuel ratio) and the percentage of fuel oxidation. The ideal voltage is deduced from the ideal power. Therefore, (d) ideal power is not equal to the product of emf with current (unless the amount of fuel utilized is infinitesimal). Examples are presented which illustrate such affects and their importance for the evaluation of ideal power and of efficiency.

Gaggioli, R.A.; Dunbar, W.R. (Marquette Univ., Milwaukee, WI (United States))

1993-06-01

54

Sources of EMF in Near Earth and Planetary Environments  

NASA Astrophysics Data System (ADS)

The realization that extensive electrical activates occur in and above the troposphere, extending to the ionosphere and ultimately coupling to the magnetosphere have raised the theoretical and experimental questions regarding the sources of EMF which create the observed effects. The current work has identified 17 Local Electrical Batteries (LEBs), which provide the electrical EMF that can be linked to the observed effects of Sprites, Elves, etc. and which additionally are shown to directly power the tropospheric storm systems and counter-rotating jet streams (rotating in the easterly direction in the northern and southern latitudes and westerly near the equator). The path of these sources of EMF can be followed from the passing solar wind through "tunnels" that end in electrical currents that pass into the atmosphere via the ionosphere to storm cloud systems in the lower atmosphere. These are the sources of electrical energy that power the severe lower atmospheric storm systems such as hurricanes and tornadoes. The model for these storm systems is included. The connection is made theoretically with the solar wind that drives the 17 identified LEBs. The dynamics of small dust particles including water molecules and droplets in the LEB environment shows that these particles become electrically charged and their Debye shielding takes on a new form which is extended from that of the neutral environment typically considered in previous theoretical models. An attempt is made to solve the fundamental problem of the source of energy that drives these systems. Previous meteorological models considered that the energy sources for lightning and other energetic phenomenon came from within the storm systems. The current work shows that the original sources of EMF are actually in the passing solar wind. Additionally, the effects of moons and their positions relative to the planet and solar wind are shown to contribute to the overall discharge phenomenon. A connection is made between these energy sources and earth quake and volcanic "trigger" mechanisms.

McCanney, J. M.

2007-12-01

55

The process of consensus on EMF: SAB review of the EPA draft document on EMF and cancer  

SciTech Connect

The EPA Draft Document on EMF and Cancers grew out of an earlier effort by EPA to track biological effects literature relative to radio-frequency (RF) exposure. Scope of the document was broadened to include extremely low frequency electric and magnetic fields prior to an announcement in 1986 that EPA would formally review the whole area of non-ionizing radiation. An extensive survey of the relevant bioeffects and epidemiologic literature was carried out, and writing on the document began in earnest on the document sometime in 1989. In its draft form, the document reviewed the literature on mechanisms of Interaction between electromagnetic fields and biological tissue, EMF epidemiologic studies, supporting evidence for carcinogenicity and research needs. In the early summer of 1990, a draft of the document was reviewed by some 22 individuals within the EPA and other government agencies. It was also sent out for external review to an additional 9 qualified scientists who had worked in the area and were familiar with EMF-related literature in epidemiology, biology, and physics. Many of the comments sent to EPA from this first review, prior to release of the draft for public comment, were strikingly similar to those resulting from the second (public) review process. Thus, it appears that much of the controversy that was later associated with the document could have been avoided had the authors been diligent in following the recommendations of the initial set of reviewers.

Wilson, B.W.

1992-06-01

56

EMF Study of the Liquid Sb-Sn-Zn Alloys  

Microsoft Academic Search

The measurement of electromotive force (EMF) of concentration cells was applied to obtain zinc activity in ternary liquid\\u000a Sb-Sn-Zn alloys in a Znliq|(KCl-LiCl)eut+ZnCl2|(Sb-Sn-Zn)liq galvanic cell. The measurements were carried out at temperatures from 723 up to 943K for different Zn concentrations X\\u000a Zn and for five constant ratios of Sn to Sb mole fractions, which were 1\\/3, 1, 3, 4

Tomasz Gancarz; W?adys?aw G?sior

57

Negative Absolute Temperatures  

Microsoft Academic Search

It is pointed out that there are a few physical systems whose temperature when measured on an absolute scale can assume negative values. Such temperatures are not colder than absolute zero; a system with a negative temperature can give heat to one at an infinite temperature and is therefore hotter. The mechanism for such negative temperatures is described, the main

Warren G. Proctor

1978-01-01

58

Absolute Lipschitz extendability  

Microsoft Academic Search

A metric space X is said to be absolutely Lipschitz extendable if every Lipschitz function f from X into any Banach space Z can be extended to any containing space Y?X, where the loss in the Lipschitz constant in the extension is independent of Y,Z, and f. We show that various classes of natural metric spaces are absolutely Lipschitz extendable.

James R. Lee; Assar Naor

2004-01-01

59

Environmental Field Surveys, EMF Rapid Program, Engineering Project No.3  

SciTech Connect

The EMF Research and Public Information Dissemination Program (RAPID) includes several engineering research in the area of exposure assessment and source characterization. RAPID engineering project No. 3: ''Environmental Field Surveys'' was performed to obtain information on the levels and characteristics of different environments, for which only limited data were available, especially in comparison to magnetic field data for the residential environment and for electric utility facilities, such as power lines and substations. This project was also to provide information on the contribution of various field sources in the surveyed environments. Magnetic field surveys were performed at four sites for each of five environments: schools, hospitals, office buildings, machine shops, and grocery stores. Of the twenty sites surveyed, 11 were located in the San Francisco Bay Area and 9 in Massachusetts. The surveys used a protocol based on magnetic field measurements and observation of activity patterns, designed to provide estimates of magnetic field exposure by type of people and by type of sources. The magnetic field surveys conducted by this project produced a large amount of data which will form a part of the EMF measurement database Field and exposure data were obtained separately for ''area exposure'' and ''at exposure points''. An exposure point is a location where persons engage in fixed, site specific activities near a local source that creates a significant increase in the area field. The area field is produced by ''area sources'', whose location and field distribution is in general not related to the location of the people in the area.

Enertech Consultants

1996-04-01

60

Discussion of an EMF (electric and magnetic field) protocol  

SciTech Connect

In 1989, three collaborating cancer research agencies initiated large-scale case-control studies of the postulated association between residential exposure to 50/60-Hz electric and magnetic fields and the induction of childhood leukemia. To facilitate design of the exposure assessment component of these studies, the Electric Power Research Institute sponsored a two-day workshop on February 6--8, 1989. The workshop's objective was to develop a detailed state-of-the science'' protocol for direct and/or surrogate measurements of a subject's EMF exposure history. Emphasis was placed on the difficulties inherent in measuring the exposure of small children. Attendees were divided into three working groups, addressing the following questions, respectively: How can historical exposure best be assessed; what should be measured outdoors; and what should be measured indoors Consensus on a single protocol was not found to be possible, given the state of knowledge about EMF exposure and the pathophysiology of childhood leukemia. However, the discussion produced a comprehensive analysis of the issues involved in addressing the crucial questions of who and what should be measured, and when, where and how these measurements should take place. In particular, discussion focused on: personal monitoring versus area measurements; exposure metrics; relevant time periods over the subjects life for measurement; location and duration of measurements; and protocol development considerations. Attendees expressed strong interest in another, similar workshop sometime in the future. 1 tab.

Afifi, A.A.; Banks, R.S.; Kheifets, L.I.; Newman, B. (Banks (Robert S.) Associates, Inc., Minneapolis, MN (USA))

1990-07-01

61

Proposed Experiment to Determine the Effect of Pressure on the emf of Thermocouples  

Microsoft Academic Search

A new experimental procedure to determine the effect of pressure on the emf-vs-temperature behavior of thermocouples has been conceived and tested with simulated data on a computer. An important advantage of this procedure is that the temperature of the hot junction can be accurately evaluated without the necessity of measuring it directly. Instead, the emf of the pressurized thermocouple is

Meyer Waxman; John R. Hastings

1972-01-01

62

Safety of High Speed Guided Ground Transportation Systems: EMF Exposure Environments. Summary Report.  

National Technical Information Service (NTIS)

The paper presents an overview of American exposure assessments for electric and magnetic fields (EMF) in the frequency range from 0 to 3 kHz. The exposure information available is very limited for all but a few occupations and sources of EMF. Much of the...

D. Goellner T. Inge L. Gillette N. Hankin B. Hostage

1993-01-01

63

Retraction: Evaluation of carcinogenic effects of electromagnetic fields (EMF).  

PubMed

The Editor-in-chief of the Bosnian Journal of Basic Medical Sciences has decided to retract the article from Bayazit V et al. [1] entitled as: "Evaluation of carcinogenic effects of electromagnetic fields (EMF)" published in Bosn J Basic Med Sci. 2010 Aug;10(3):245-50. After the editorial office was alerted of possible plagiarism in the article, it conducted thorough investigation and concluded that the article apparently represents plagiarized material from two World Health Organization reports, one European Commission report and other sources. Since this is considered scientific plagiarism and scientific misconduct, Editor-in-chief has decided to withdraw the article. The authors have agreed with the editorial office decision. PMID:21108618

Mehic, Bakir

2010-11-01

64

Sharpening the focus in EMF research. [Electric and Magnetic Fields  

SciTech Connect

Research results have yet to settle whether or not exposure to magnetic fields can adversely affect human health, but recent studies have provided strong pointers to several fertile areas of inquiry. EPRI is planning new studies that will dig deeper into the mysteries of these key focus areas, including questions about what wire code classifications really represent as indicators of residential magnetic field exposure and whether they are appropriate surrogates for actual exposure measurements. Other questions surround the hypothesis that magnetic fields could suppress production of the hormone melatonin, representing a possible mechanism of biological interaction. In addition to health studies, EPRI is continuing work in other parts of its comprehensive EMF research program, which includes identification of significant field sources and investigation of potential field management methods.

Moore, T. (Electric Power Research Inst., Palo Alto, CA (United States))

1992-03-01

65

Idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF): A systematic review of identifying criteria  

PubMed Central

Background Idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) remains a complex and unclear phenomenon, often characterized by the report of various, non-specific physical symptoms (NSPS) when an EMF source is present or perceived by the individual. The lack of validated criteria for defining and assessing IEI-EMF affects the quality of the relevant research, hindering not only the comparison or integration of study findings, but also the identification and management of patients by health care providers. The objective of this review was to evaluate and summarize the criteria that previous studies employed to identify IEI-EMF participants. Methods An extensive literature search was performed for studies published up to June 2011. We searched EMBASE, Medline, Psychinfo, Scopus and Web of Science. Additionally, citation analyses were performed for key papers, reference sections of relevant papers were searched, conference proceedings were examined and a literature database held by the Mobile Phones Research Unit of Kings College London was reviewed. Results Sixty-three studies were included. Hypersensitivity to EMF was the most frequently used descriptive term. Despite heterogeneity, the criteria predominantly used to identify IEI-EMF individuals were: 1. Self-report of being (hyper)sensitive to EMF. 2. Attribution of NSPS to at least one EMF source. 3. Absence of medical or psychiatric/psychological disorder capable of accounting for these symptoms 4. Symptoms should occur soon (up to 24?hours) after the individual perceives an exposure source or exposed area. (Hyper)sensitivity to EMF was either generalized (attribution to various EMF sources) or source-specific. Experimental studies used a larger number of criteria than those of observational design and performed more frequently a medical examination or interview as prerequisite for inclusion. Conclusions Considerable heterogeneity exists in the criteria used by the researchers to identify IEI-EMF, due to explicit differences in their conceptual frameworks. Further work is required to produce consensus criteria not only for research purposes but also for use in clinical practice. This could be achieved by the development of an international protocol enabling a clearly defined case definition for IEI-EMF and a validated screening tool, with active involvement of medical practitioners.

2012-01-01

66

Absolute neutrino mass scale  

NASA Astrophysics Data System (ADS)

Neutrino oscillation experiments firmly established non-vanishing neutrino masses, a result that can be regarded as a strong motivation to extend the Standard Model. In spite of being the lightest massive particles, neutrinos likely represent an important bridge to new physics at very high energies and offer new opportunities to address some of the current cosmological puzzles, such as the matter-antimatter asymmetry of the Universe and Dark Matter. In this context, the determination of the absolute neutrino mass scale is a key issue within modern High Energy Physics. The talks in this parallel session well describe the current exciting experimental activity aiming to determining the absolute neutrino mass scale and offer an overview of a few models beyond the Standard Model that have been proposed in order to explain the neutrino masses giving a prediction for the absolute neutrino mass scale and solving the cosmological puzzles.

Capelli, Silvia; Di Bari, Pasquale

2013-04-01

67

Absolute radiation detector  

NASA Astrophysics Data System (ADS)

An absolute radiation detector (a cryogenic radiometer) is being developed to replace the existing UK primary national standard cryogenic radiometer with an improved uncertainty. The cryogenic radiometer will be capable of measuring black body radiation and laser radiation with an uncertainty approaching 10 ppm. From these measurements it will be possible to determine the fundamental constant, the Stefan Boltzmann constant, confirming the radiometer as an absolute detector, and link this determination to the SI unit of luminous intensity, the candela. Thus detector and source based scales/standards will be tied to an invariant physical quantity ensuring their long-term stability.

Martin, John E.

1996-11-01

68

Precise determination of the absolute isotopic abundance ratio and the atomic weight of chlorine in three international reference materials by the positive thermal ionization mass spectrometer-Cs2Cl+-graphite method.  

PubMed

Because the variation in chlorine isotopic abundances of naturally occurring chlorine bearing substances is significant, the IUPAC Inorganic Chemistry Division, Commission on Isotopic Abundances and Atomic Weights (CIAAW-IUPAC) decided that the uncertainty of atomic weight of chlorine (A(r)(Cl)) should be increased so that the implied range was related to terrestrial variability in 1999 (Coplen, T. B. Atomic weights of the elements 1999 (IUPAC Technical Report), Pure Appl. Chem.2001, 73(4), 667-683; and then, it emphasized that the standard atomic weights of ten elements including chlorine were not constants of nature but depend upon the physical, chemical, and nuclear history of the materials in 2009 (Wieser, M. E.; Coplen, T. B. Pure Appl. Chem.2011, 83(2), 359-396). According to the agreement by CIAAW that an atomic weight could be defined for one specified sample of terrestrial origin (Wieser, M. E.; Coplen, T. B. Pure Appl. Chem.2011, 83(2), 359-396), the absolute isotope ratios and atomic weight of chlorine in standard reference materials (NIST 975, NIST 975a, ISL 354) were accurately determined using the high-precision positive thermal ionization mass spectrometer (PTIMS)-Cs(2)Cl(+)-graphite method. After eliminating the weighing error caused from evaporation by designing a special weighing container and accurately determining the chlorine contents in two highly enriched Na(37)Cl and Na(35)Cl salts by the current constant coulometric titration, one series of gravimetric synthetic mixtures prepared from two highly enriched Na(37)Cl and Na(35)Cl salts was used to calibrate two thermal ionization mass spectrometers in two individual laboratories. The correction factors (i.e., K(37/35) = R(37/35meas)/R(37/35calc)) were obtained from five cycles of iterative calculations on the basis of calculated and determined R((37)Cl/(35)Cl) values in gravimetric synthetic mixtures. The absolute R((37)Cl/(35)Cl) ratios for NIST SRM 975, NIST 975a, and ISL 354 by the precise calibrated isotopic composition measurements are 0.319876 0.000067, 0.319768 0.000187, and 0.319549 0.000044, respectively. As a result, the atomic weights of chlorine in NIST 975, NIST 975a, and ISL 354 are derived as 35.45284(8), 35.45272(21), and 35.45252(2) individually, which are consistent with the issued values of 35.453(2) by IUPAC in 1999. PMID:23088631

Wei, Hai-Zhen; Jiang, Shao-Yong; Xiao, Ying-Kai; Wang, Jun; Lu, Hai; Wu, Bin; Wu, He-Pin; Li, Qing; Luo, Chong-Guang

2012-11-02

69

NOVA: Absolute Zero  

NSDL National Science Digital Library

This NOVA website contains information about the scientific quest to utilize cold and to achieve the lowest temperature possible. Several interactive simulations present topics such as the states of matter, the anatomy of a refrigerator, and a virtual lab to achieve low temperatures. The site also includes articles on absolute hot, ultra-cold atoms, and milestones in cold research.

2008-04-06

70

Relative and Absolute Directions  

NSDL National Science Digital Library

The purpose of this resource is to learn about latitude and longitude while developing math skills. Students begin by asking the simple question: 'Where Am I?' Then they learn about the magnetic Earth and the use of compasses and angles. Students also learn about the difference between relative and absolute locations. Throughout this activity, students practice using a variety of math skills.

The GLOBE Program, University Corporation for Atmospheric Research (UCAR)

2003-08-01

71

Absolute configuration of franganine.  

PubMed

The absolute configuration of franganine (1), a cyclopeptide alkaloid isolated from the methanol root bark extract of Discaria americana, was established on the basis of detailed NMR spectroscopic data and X-ray diffraction analysis of its salt (2). PMID:22680778

Caro, Miguel S B; de Oliveira, Leonardo H; Ilha, Vinicius; Burrow, Robert A; Dalcol, Ionara I; Morel, Ademir F

2012-06-08

72

Study of uranium solubility in gallium-indium eutectic alloy by emf method  

NASA Astrophysics Data System (ADS)

Activity, activity coefficients and solubility of uranium in Ga-In eutectic alloy as well as activity of uranium in U-Ga and U-In alloys were determined between 573 and 1073 K using electromotive force (emf) method.

Volkovich, V. A.; Maltsev, D. S.; Yamshchikov, L. F.; Osipenko, A. G.; Raspopin, S. P.; Kormilitsyn, M. V.

2013-02-01

73

REAL-TIME MEASUREMENT OF BRAIN MICROCIRCULATION DURING RF-EMF EXPOSURE USING AN \\  

Microsoft Academic Search

Aim of present study was to investigate whether radio frequency electromagnetic field (RF-EMF) exposure induces reversible effects on brain microcirculation observable only during exposure. Using our developed ''8''-shaped loop

H. Masuda; A. Ushiyama; S. Hirota; S. Watanabe; Y. Yamanaka; C. Ohkubo

74

Scheme for Incorporating DC Magnetic Fields into Epidemiological Studies of EMF Exposure.  

National Technical Information Service (NTIS)

Experimental data on calcium-ion release in chicken brain tissue suggest that biological effects of electric and magnetic fields (EMFs) are concentrated near certain 'active combinations' of DC magnetic field strength and 'effective' AC magnetic field fre...

C. F. Blackman B. Most

1993-01-01

75

RF-EMF exposure of fetus and mother during magnetic resonance imaging  

Microsoft Academic Search

Magnetic resonance imaging (MRI) avoids risks of genetic damage but may be associated with excess heating of body tissues. To investigate the exposure to MRI radio-frequency (RF) electromagnetic fields (EMF), low-pass and high-pass birdcage coils were simulated and the whole-body pregnant woman model SILVY used to determine local and whole-body specific absorption rates (SAR) in mother and fetus. Resonant RF-EMF

M. Pediaditis; N. Leitgeb; R. Cech

2008-01-01

76

Use of C. Elegans as a model organism for sensing the effects of ELF-EMFs  

Microsoft Academic Search

For the past two decades, there have been concerns and controversy about the effects on human health of the increased exposure to extremely-low-frequency (ELF) electromagnetic fields (EMFs) resulting from electrification, in both residential and industrial settings. Several epidemiological studies have implicated ELF-EMFs averaging 0.4 ?mUTesla (T) or more in increased risk of cancer, especially childhood leukaemia [1,2]; there have also

A H Lacchini; M L Everington; A T Augousti; A J Walker

2007-01-01

77

Use of C. Elegans as a model organism for sensing the effects of ELF-EMFs  

Microsoft Academic Search

For the past two decades, there have been concerns and controversy about the effects on human health of the increased exposure to extremely-low-frequency (ELF) electromagnetic fields (EMFs) resulting from electrification, in both residential and industrial settings. Several epidemiological studies have implicated ELF-EMFs averaging 0.4 mumUTesla (T) or more in increased risk of cancer, especially childhood leukaemia [1,2]; there have also

A. H. Lacchini; M. L. Everington; A. T. Augousti; A. J. Walker

2007-01-01

78

Absolute Neutron Flux of the Agn-201 Reactor.  

National Technical Information Service (NTIS)

Absolute total and thermal neutron flux of the U. S. Naval Postgraduate School's AGN-201 reactor was determined by neutron activation of thin gold foils. Foil activities were measured with a gamma-ray scintillation spectrometer, using methods designed to ...

R. E. Perry

1964-01-01

79

EMF is a serious issue and needs a rational plan  

SciTech Connect

Magnetic fields may be the most serious issue facing the electric utility industry in this decade. The implications that electricity might cause a dread disease in children are profound, since our society has become so dependent of this versatile energy form. Although irrefutable scientific proof has not been obtained showing a definite link between magnetic fields and cancer, there is reasonable cause for concern. Evidence is conflicting. Everyone anxiously waits for the results of the next study. Vigorous debate rages over results, techniques and implications. Many utilities, caught in the middle of this controversy, are taking a proactive role in research and communications with the public. The public, however, is beginning to demand action. They want to know how to make their homes, offices and schools free from this apparently menacing invader. This article describes present research in the field, how research results are presented to and received by the public, and what electric utilities can do to take a proactive stance in the debate over EMF health effects while maintaining good communication and relations with the public.

Young, F.S.

1993-06-01

80

Absolute beam brightness detector  

SciTech Connect

In generally accepted emittance measurement, main attention is concentrated on emittance areas {epsilon}{sub x}, {epsilon}{sub y} occupied by desired part of ion beam in transverse phase space and shape of these areas. The absolute beam phase density (brightness) as usually is not measured directly and the average beam brightness B is calculated from a beam intensity I and the transverse emittances. In the ion source and low energy beam transport (LEBT) optimization, it is important to preserve the beam brightness because some aberration of ion optic and beam instabilities can decrease the brightness of the central part of ion beam significantly. For these brightness measurements, it is convenient to use an absolute beam brightness detector with the brightness determination from one short considered in this article.

Dudnikov, Vadim [Muons, Inc., Batavia, Illinois 60510 (United States)

2012-02-15

81

Absolute E-rings  

Microsoft Academic Search

A ring R with 1 is called an E-ring if EndZR is ring-isomorphic to R under the canonical homomorphism taking the value 1? for any ??EndZR. Moreover R is an absolute E-ring if it remains an E-ring in every generic extension of the universe. E-rings are an important tool for algebraic topology as explained in the introduction. The existence of

Rdiger Gbel; Daniel Herden; Saharon Shelah

2011-01-01

82

Exposure of rats to extremely low-frequency electromagnetic fields (ELF-EMF) alters cytokines production.  

PubMed

Investigations indicate a potential link between exposure to extremely low-frequency electromagnetic field (ELF-EMF) and some cancers. Carcinogenesis of ELF-EMF may be mediated by effect on the immune system. During an immune response, nave T cells differentiate to effector type 1 helper T cells (T(H)1), T(H)2, or T(H)17 subsets according to existence of different cytokines and T(H)1 is important in defense against tumors. Therefore, it will be reasonable to test whether ELF-EMF can change cytokines like interferon gamma (IFN-?), interleukin-4 (IL-4), IL-6, and IL-12 that regulate T(H)1/T(H)2/T(H)17 balance. Forty adult male rats were randomly separated into ELF-EMF-exposed and sham-exposed control groups. The ELF-EMF group was exposed to a flux density of 100?T, frequency 50Hz, 2h/day for 3 months. The controls were placed in identical chamber without ELF-EMF. The results showed there were no significant differences between the mean mass of rats, thymuses, and spleens in ELF-EMF exposed group compared with controls. Serum IL-12 level was decreased from 41847pg/ml in controls to 30023pg/ml (p<0.05) in ELF-EMF-exposed group. Phytohemagglutinin activated of in vitro production of IL-6 by the whole spleen culture (135692pg/ml) and total blood culture (41840pg/ml) of ELF-EMF-exposed rats were higher (p<0.001) comparing with controls (90574pg/ml), (18226pg/ml), respectively. However, the levels of IFN-?, IL-4, and IL-6 of serum and IFN-?, IL-4, and IL-12 in spleen culture and total blood culture of two groups were not significantly different. It seems that ELF-EMF may change T(H)1/T(H)2/T(H)17 balance toward down regulation of T(H)1 and upregulation T(H)17 type responses. PMID:23046051

Salehi, Iraj; Sani, Karim Ghazikhanlou; Zamani, Alireza

2012-10-09

83

Variation in cancer risk estimates for exposure to powerline frequency electromagnetic fields: A meta-analysis comparing EMF measurement methods  

Microsoft Academic Search

We used meta-analysis to synthesize the findings from eleven case-control studies on cancer risks in humans exposed to 50-60 Hertz powerline electromagnetic fields (EMFs). Pooled estimates of risk are derived for different EMF measurement methods and types of cancer. EMF measurement methods are classified as: wiring configuration codes, distance to power distribution equipment, spot measurements of magnetic fields, and calculated

Michelle A. Miller; James R. Murphy; Thomas I Miller; A. J. Ruttenber

1995-01-01

84

Absolute airborne gravimetry  

NASA Astrophysics Data System (ADS)

This work consists of a feasibility study of a first stage prototype airborne absolute gravimeter system. In contrast to relative systems, which are using spring gravimeters, the measurements acquired by absolute systems are uncorrelated and the instrument is not suffering from problems like instrumental drift, frequency response of the spring and possible variation of the calibration factor. The major problem we had to resolve were to reduce the influence of the non-gravitational accelerations included in the measurements. We studied two different approaches to resolve it: direct mechanical filtering, and post-processing digital compensation. The first part of the work describes in detail the different mechanical passive filters of vibrations, which were studied and tested in the laboratory and later in a small truck in movement. For these tests as well as for the airborne measurements an absolute gravimeter FG5-L from Micro-G Ltd was used together with an Inertial navigation system Litton-200, a vertical accelerometer EpiSensor, and GPS receivers for positioning. These tests showed that only the use of an optical table gives acceptable results. However, it is unable to compensate for the effects of the accelerations of the drag free chamber. The second part describes the strategy of the data processing. It is based on modeling the perturbing accelerations by means of GPS, EpiSensor and INS data. In the third part the airborne experiment is described in detail, from the mounting in the aircraft and data processing to the different problems encountered during the evaluation of the quality and accuracy of the results. In the part of data processing the different steps conducted from the raw apparent gravity data and the trajectories to the estimation of the true gravity are explained. A comparison between the estimated airborne data and those obtained by ground upward continuation at flight altitude allows to state that airborne absolute gravimetry is feasible and has a spatial resolution comparable to the one of the relative airborne gravimetry. For a wavelength on the order of 11 km the mean value of the resolution of the estimated gravity is 9.7 mGal. Finally some suggestions are formulated for the improvement of the system which should simplify its use, increase the accuracy and reduce its price.

Baumann, Henri

85

Absolute configuration of odorine  

PubMed Central

The title compound, known as odorine or roxburghiline {systematic name: (S)-N-[(R)-1-cinnamoylpyrrolidin-2-yl]-2-methylbutanamide}, C18H24N2O2, is a nitrogenous compound isolated from the leaves of Aglaia odorata. The absolute configuration was determined by refinement of the Flack parameter with data collected using Cu K? radiation showing positions 2 and 2? to be S and R, respectively. The pyrrolidine ring adopts an envelope conformation. In the crystal, molecules are linked into chains along [010] by intermolecular NH?O hydrogen bonds.

Fun, Hoong-Kun; Chantrapromma, Suchada; Yodsaoue, Orapun; Karalai, Chatchanok

2010-01-01

86

Absolute configuration of odorine.  

PubMed

The title compound, known as odorine or roxburghiline {systematic name: (S)-N-[(R)-1-cinnamoylpyrrolidin-2-yl]-2-methyl-butanamide}, C(18)H(24)N(2)O(2), is a nitro-genous compound isolated from the leaves of Aglaia odorata. The absolute configuration was determined by refinement of the Flack parameter with data collected using Cu K? radiation showing positions 2 and 2' to be S and R, respectively. The pyrrolidine ring adopts an envelope conformation. In the crystal, mol-ecules are linked into chains along [010] by inter-molecular N-H?O hydrogen bonds. PMID:21588760

Fun, Hoong-Kun; Chantrapromma, Suchada; Yodsaoue, Orapun; Karalai, Chatchanok

2010-08-28

87

The absolute isotopic composition of europium  

NASA Astrophysics Data System (ADS)

Calibrated mass spectrometric measurements on highly enriched isotopes of europium in the form of 99.96% pure sesquioxide were carried out with a thermal ionization mass spectrometer, yielding an absolute isotopic composition of 47.810(42) at.% 151Eu and 52.190(42) at.% 153Eu, and the atomic weight of europium as 151.9644(9) with error given as 2[sigma]. No isotopic fractionation was found in terrestrial normal europium materials.

Chang, Tsing Lien; Qian, Qiu-Yu; Zhao, Mo-Tian; Wang, Jun

1994-11-01

88

ABSOLUTE POLARIMETRY AT RHIC.  

SciTech Connect

Precise and absolute beam polarization measurements are critical for the RHIC spin physics program. Because all experimental spin-dependent results are normalized by beam polarization, the normalization uncertainty contributes directly to final physics uncertainties. We aimed to perform the beam polarization measurement to an accuracy Of {Delta}P{sub beam}/P{sub beam} < 5%. The absolute polarimeter consists of Polarized Atomic Hydrogen Gas Jet Target and left-right pairs of silicon strip detectors and was installed in the RHIC-ring in 2004. This system features proton-proton elastic scattering in the Coulomb nuclear interference (CNI) region. Precise measurements of the analyzing power A{sub N} of this process has allowed us to achieve {Delta}P{sub beam}/P{sub beam} = 4.2% in 2005 for the first long spin-physics run. In this report, we describe the entire set up and performance of the system. The procedure of beam polarization measurement and analysis results from 2004-2005 are described. Physics topics of AN in the CNI region (four-momentum transfer squared 0.001 < -t < 0.032 (GeV/c){sup 2}) are also discussed. We point out the current issues and expected optimum accuracy in 2006 and the future.

OKADA; BRAVAR, A.; BUNCE, G.; GILL, R.; HUANG, H.; MAKDISI, Y.; NASS, A.; WOOD, J.; ZELENSKI, Z.; ET AL.

2007-09-10

89

Electromagnetic fields and the public: EMF standards and estimation of risk  

NASA Astrophysics Data System (ADS)

Mobile communications are a relatively new and additional source of electromagnetic exposure for the population. Standard daily mobile-phone use is known to increase RF-EMF (radiofrequency electromagnetic field) exposure to the brains of users of all ages, whilst mobile-phone base stations, and base station units for cordless phones, can regularly increase the exposures of large numbers of the population to RF-EMF radiation in everyday life. The need to determine appropriate standards stipulating the maximum acceptable short-term and long-term RF-EMF levels encountered by the public, and set such levels as general guidelines, is of great importance in order to help preserve the general public's health and that of the next generation of humanity.

Grigoriev, Yury

2010-04-01

90

Standard gibbs energies of formation of the carbides of chromium by emf measurements  

NASA Astrophysics Data System (ADS)

The standard Gibbs energies of formation of Cr3C2, Cr7C3, and Cr23C6 have been determined by electromotive force (emf) measurements using galvanic cells of the type (-) Cr, CrF2, CaF2 // CaF2 // CaF2, CrF2, Cr-C (+) The measurements have been carried out in the temperature range 1002 to 1176 K. The ? G values obtained in the present work are generally in agreement with some of the earlier emf measurements but differ significantly from those obtained by Cr2O3-CO equilibrium studies.

Sichen, Du; Sheetharaman, S.; Staffansson, L.-I.

1989-12-01

91

Melatonin and puberty in female lambs exposed to EMF: A replicate study  

SciTech Connect

In an earlier study, the authors found no effects of 60 Hz electric and magnetic fields (EMF) from a 500 kV transmission line on serum melatonin patterns or on puberty in ten female Suffolk lambs (Ovis aries). The authors conducted a larger replicate study of 15 lambs exposed to a mean electric field of 6.3 kV/m and a mean magnetic field of 3.77 {mu}T and 15 controls exposed to EMF two orders of magnitude weaker than in the line area. The replicate produced essentially the same results as their previous study.

Lee, J.M. Jr. [Bonneville Power Administration, Portland, OR (United States); Stormshak, F.; Thompson, J.M. [Oregon State Univ., Corvallis, OR (United States). Dept. of Animal Sciences; Hess, D.L. [Oregon Regional Primate Research Center, Beaverton, OR (United States); Foster, D.L. [Univ. of Michigan, Ann Arbor, MI (United States)

1995-06-01

92

Electrical conductivity and thermo-emf of melts of the system Tl-Te-Se  

SciTech Connect

A study was made of the temperature dependences of the electrical conductivity and thermo-emf of melts of ternary system Tl-Te-Se from the melting point to 1000 K. Concentration dependences of these parameters were also established. The data obtained were used with data for binary systems to construct isothermal surfaces of electrical conductivity and thermo-emf for the system Tl-Te-Se at T = 750 K. The results show that it is possible to control the electronic properties of melts of complex semiconductor systems having lamination regions.

Kazandzhan, B.I.; Matveev, V.M.; Umarov, A.M.

1988-07-01

93

Is the Risk Comparison Made by the Public Between EMF and Smoking or Asbestos a Valid One?  

Microsoft Academic Search

The possibility of adverse health effects from exposure to extremely low frequency (ELF) electric and magnetic fields (EMF) has caused considerable controversy in the scientific community and has received great attention in the media and among the general public with many comparing ELF EMF with tobacco smoking and asbestos. Although both smoking and asbestos are now classified by the International

Ken K. Karipidis

2007-01-01

94

Effect of pole to slot number ratio on back-EMF constant of BLDC motor with nonoverlapping stator winding  

Microsoft Academic Search

This paper presents a general expression of back-EMF constant of 3-phase permanent magnet brushless DC (BLDC) motor with nonoverlapping stator winding. From the expression, any possible combinations of pole and slot numbers are found and the value of back-EMF constant is compared in the several cases of different pole to slot number ratios and airgap flux density waveforms

Han-Sam Cho; Hyun-Rae Cho; Hae-Seok Lee

1999-01-01

95

Design aspects of a high-speed sensorless brushless dc motor using third harmonic back-emf for sensorless control  

NASA Astrophysics Data System (ADS)

There is increasing interest in high-speed permanent magnet (PM) brushless dc motors for a wide range of applications. Back-emf is often utilized for sensorless operation of permanent magnet brushless dc motors, by detecting the emf zero crossings. However, in high-speed motors, the free-wheeling diode conduction can last more than 30 e deg. This can obscure the zero crossings of the phase EMF; therefore, it is preferable to utilize the third harmonic emf instead of the phase emf. In this paper, some design aspects related to this high-speed sensorless operation are presented, including a special nonoverlapping winding arrangement and magnet segmenting technique. Finally, the experimental results confirmed the validity of the proposed design method.

Wang, Kai; Shen, Jianxin; Zhou, Fengzheng; Fei, Weizhong

2008-04-01

96

The impact of background radiation, illumination and temperature on EMF-induced changes of aqua medium properties.  

PubMed

The effects of extremely low frequency electromagnetic field (ELF EMF) on physicochemical properties of physiological solution at different environmental media were studied. The existence of frequency "windows" at 4 and 8Hz frequencies of ELF EMF having effects on heat fusion period, hydrogen peroxide (H2O2) formation and oxygen (O2) content of water solution and different dependency on temperature, background radiation and illumination was shown. Obtained data allow us to suggest that EMF-induced effect on water physicochemical properties depends on abovementioned environmental factors. As cell bathing medium is a target for biological effects of ELF EMF, the variability of experimental data on biological effects of EMF, obtained in different laboratories, can be explained by different environmental conditions of experiments, which very often are not considered adequately. PMID:23323624

Naira, Baghdasaryan; Yerazik, Mikayelyan; Anna, Nikoghosyan; Sinerik, Ayrapetyan

2013-01-16

97

Relation between surface adsorption states and emf in a solid electrolyte concentration cell during carbon monoxide oxidation on platinum studied by local current measurement  

SciTech Connect

The importance of measuring adsorption during surface catalysis has been emphasized often. This is true for the oxidation of carbon monoxide on a platinum surface. Surface adsorption states during the reaction under steady states can be learned from electromotive force (emf) measurement with appropriate assumptions. Two mechanisms for emf generation have been proposed, one is that only oxygen activity generates emf, the other is that both oxygen and CO adsorption generates emf.

Okamoto, H.; Kawamura, G.; Kudo, T.

1984-04-01

98

Absolute and other tolerances  

SciTech Connect

In a production process it is necessary to specify tolerances for characteristics such as dimensions, within which the measured characteristic must fall in order for the part to be acceptable. This tolerance can be based on both functional requirements and an allowance for measurement error. Sandia National Laboratories has provided general guidance for setting tolerances for its parts in Sandia General Requirements Specification 9900000, Sec. 3.3.2, titled Absolute Tolerance Concept. Implementing this guidance, particularly for parts other than Sandia's, has been a source of controversy, so in 1986 a Working Group of DOE statisticians undertook a study of statistical aspects of tolerance specification. This report presents the Group's analysis and findings. Several measures of consumer's risk were defined and then evaluated with respect to computational convenience, information requirement, rationale, and economic considerations. As an aid in setting tolerances, several cost models were considered and the optimum tolerances derived and compared. Because cost considerations have a major effect on the choice of tolerances, it is recommended that design and production personnel attempt to realistically model the cost of nonconformance in jointly arriving at appropriate measurement tolerances. 9 refs., 4 figs., 4 tabs.

Easterling, R.G.; Johnson, M.E.; Bement, T.R.; Nachtsheim, C.J.

1989-02-01

99

Absolute configuration of isoeichlerialactone.  

PubMed

The title seco-dammarane triterpenoid, C(27)H(42)O(4) (systematic name: 3-{(3S,3aR,5aR,6S,7S,9aR,9bR)-6,9a,9b-trimethyl-3-[(R)-2-methyl-5-oxotetra-hydro-furan-2-yl]-7-(prop-1-en-2-yl)dodeca-hydro-1H-cyclo-penta-[a]naphthalen-6-yl}propanoic acid), has been isolated for the first time from the seeds of Aglaia forbesii. The mol-ecule has three fused rings and all rings are in trans-fused. The two cyclo-hexane rings are in standard chair conformations and the cyclo-pentane ring adopts an envelope conformation. Its absolute configuration was determined by the refinement of the Flack parameter to 0.26?(17). In the crystal, mol-ecules are linked into chains along [010] by O-H?O hydrogen bonds. PMID:21580698

Fun, Hoong-Kun; Joycharat, Nantiya; Voravuthikunchai, Supayang Piyawan; Chantrapromma, Suchada

2010-03-20

100

Absolute configuration of isoeichlerialactone  

PubMed Central

The title seco-dammarane triterpenoid, C27H42O4 (systematic name: 3-{(3S,3aR,5aR,6S,7S,9aR,9bR)-6,9a,9b-trimethyl-3-[(R)-2-methyl-5-oxotetrahydrofuran-2-yl]-7-(prop-1-en-2-yl)dodecahydro-1H-cyclopenta[a]naphthalen-6-yl}propanoic acid), has been isolated for the first time from the seeds of Aglaia forbesii. The molecule has three fused rings and all rings are in trans-fused. The two cyclohexane rings are in standard chair conformations and the cyclopentane ring adopts an envelope conformation. Its absolute configuration was determined by the refinement of the Flack parameter to 0.26?(17). In the crystal, molecules are linked into chains along [010] by OH?O hydrogen bonds.

Fun, Hoong-Kun; Joycharat, Nantiya; Voravuthikunchai, Supayang Piyawan; Chantrapromma, Suchada

2010-01-01

101

Absolute neutrino mass measurements  

SciTech Connect

The neutrino mass plays an important role in particle physics, astrophysics and cosmology. In recent years the detection of neutrino flavour oscillations proved that neutrinos carry mass. However, oscillation experiments are only sensitive to the mass-squared difference of the mass eigenvalues. In contrast to cosmological observations and neutrino-less double beta decay (0v2{beta}) searches, single {beta}-decay experiments provide a direct, model-independent way to determine the absolute neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high accuracy.Currently the best kinematic upper limits on the neutrino mass of 2.2eV have been set by two experiments in Mainz and Troitsk, using tritium as beta emitter. The next generation tritium {beta}-experiment KATRIN is currently under construction in Karlsruhe/Germany by an international collaboration. KATRIN intends to improve the sensitivity by one order of magnitude to 0.2eV. The investigation of a second isotope ({sup 137}Rh) is being pursued by the international MARE collaboration using micro-calorimeters to measure the beta spectrum. The technology needed to reach 0.2eV sensitivity is still in the R and D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2{beta} decay and single {beta}-decay.

Wolf, Joachim [Karlsruhe Institute of Technology (KIT), IEKP, Postfach 3640, 76021 Karlsruhe (Germany)

2011-10-06

102

Absolute Zero: Science Educator's Guide  

NSDL National Science Digital Library

This guide provides recommendations for curricular modules on low temperature physics. Designed for teachers and informal educators of middle school students. this guide complements the Absolute Zero Community Education Outreach Guide. Suggestions on leading discussions, increasing student participation, and the use of inquiry are included. This material is related to a two-part public broadcasting special, Absolute Zero, produced by Meridian Productions and Windfall Films. Absolute Zero is underwritten by the National Science Foundation and the Alfred P. Sloan Foundation and is based largely on Tom Shachtmans acclaimed book, Absolute Zero and the Conquest of Cold.

2008-09-18

103

Electromagnetic fields (EMFs) and adenosine receptors modulate prostaglandin E(2) and cytokine release in human osteoarthritic synovial fibroblasts.  

PubMed

Synovial fibroblasts (SFs) contribute to the development of osteoarthritis (OA) by the secretion of a wide range of pro-inflammatory mediators, including cytokines and lipid mediators of inflammation. Previous studies suggest that electromagnetic fields (EMFs) may represent a potential therapeutic approach to limit cartilage degradation and control inflammation associated to OA, and that they may act through the adenosine pathway. Therefore, we investigated whether EMFs might modulate inflammatory activities of human SFs from OA patients (OASFs) treated with interleukin-1? (IL-1?), and the possible involvement of adenosine receptors (ARs) in mediating EMF effects. EMF exposure induced a selective increase in A(2A) and A(3) ARs. These increases were associated to changes in cAMP levels, indicating that ARs were functionally active also in EMF-exposed cells. Functional data obtained in the presence of selective A(2A) and A(3) adenosine agonists and antagonists showed that EMFs inhibit the release of prostaglandin E(2) (PGE(2)) and the proinflammatory cytokines interleukin-6 (IL-6) and interleukin-8 (IL-8), while stimulating the release of interleukin-10 (IL-10), an antinflammatory cytokine. These effects seem to be mediated by the EMF-induced upregulation of A(2A) and A(3) ARs. No effects of EMFs or ARs have been observed on matrix degrading enzyme production. In conclusion, this study shows that EMFs display anti-inflammatory effects in human OASFs, and that these EMF-induced effects are in part mediated by the adenosine pathway, specifically by the A(2A) and A(3) AR activation. Taken together, these results open new clinical perspectives to the control of inflammation associated to joint diseases. PMID:21830213

Ongaro, A; Varani, K; Masieri, F F; Pellati, A; Massari, L; Cadossi, R; Vincenzi, F; Borea, P A; Fini, M; Caruso, A; De Mattei, M

2012-06-01

104

The opportunities of two-phase hybrid stepping motor back EMF sampling  

Microsoft Academic Search

By counting the step command pulses, stepping motors can be straightforwardly used for open loop positioning. However, open-loop control is often insufficient to guarantee accurate and energy efficient movements. More intelligent stepping motor algorithms can meet these concerns, however, this requires position information. The back EMF signal contains useful information on the rotor position. This information can be used to

S. Derammelaere; L. Carlier; B. Vervisch; C. Debruyne; K. Stockman; P. Cox; L. Vandevelde; G. Van den Abeele

2011-01-01

105

Overview: The emf method as a source of experimental thermodynamic data  

Microsoft Academic Search

The use of galvanic cells to determine the thermodynamic properties of metallic or ceramic materials from electromotive force (emf) measurements is described. Two basic types of the method are distinguished: those employing liquid electrolytes and those based on solid ion-conducting electrolytes. Liquid electrolytes can be aqueous solutions, but for thermodynamic measurements in metallic materials molten salt mixtures with the addition

Herbert Ipser; Adolf Mikula; Iwao Katayama

2010-01-01

106

Online Survey of Children's Understanding of Mobile Phones and EMF: Preliminary Results  

Microsoft Academic Search

An ongoing global online survey was initiated in October 2005 to compile and analyse information on the understanding of mobile phone technology and EMF among school children. Since November 2005 and till July 23, 2006, a total of 1,711 responses were recorded from 60 countries. The number of male respondents (n = 653, 38.2%) roughly equalled the female (n =

N. Adib Kadri; Kwan-Hoong Ng; Li-Kuo Tan; Jin-Wooi Tan; Siew-Eng Lee; Heng-Loke Siow

2006-01-01

107

Can EMF exposure during development leave an imprint later in life?  

PubMed

People in industrialized nations live in an environment of ubiquitous electromagnetic field (EMF) exposure, both natural and anthropogenic. The intensity, variety, and geographic distribution of anthropogenic EMF exposures have grown dramatically since the mid 20th century, with many uses serving, and in close proximity to, human populations, such as electric power distribution, radio and television transmission, and more recently, personal cell phone communication units and transmitting towers. Thus, it is reasonable to ask if this EMF exposure could cause alterations in the physiology of developing organisms, since they are generally assumed to be the most sensitive to chemical stressors. In this report, we review work published beginning in the late 1980s. Initial reports indicated that exposure of chicken eggs during embryonic development to power-line electric fields of 50 and 60 Hz, at 10 V/m in air (which is frequently in locations inhabited by humans), could cause the brain tissues of the hatched chickens to respond differently in a particular test. More recently, an anecdotal report of human sensitivity to EMF has appeared that shows a health-related influence of prior exposure history to particular power-line frequencies in chemically sensitized individuals. These reports open the question of whether the ambient electromagnetic environment can leave an imprint on developing organisms and if such imprint changes have the potential for health consequences. PMID:17178582

Blackman, Carl F

2006-01-01

108

Direct torque control of brushless DC motor with nonideal trapezoidal back EMF  

Microsoft Academic Search

In this paper a method of the torque control attenuating the undesired torque pulsation for brushless DC motor with nonideal trapezoidal back EMF is presented. It is the direct torque control method in which the applied output voltage is calculated from the reference torque and the torque of the previous step in the two-phase conducting period and in the commutation

Seog-Joo Kang; Seung-Ki Sul

1995-01-01

109

Hybrid sensorless control of IPMSM Combining high frequency injection method and back EMF method  

Microsoft Academic Search

This paper introduces a new hybrid sensorless control of interior permanent magnet synchronous machines (IPMSM) combining high frequency injection and back EMF based method. The proposed control system realizes position, speed, and torque control in the entire speed range. Owing to the reliability and the space-saving feature, the sensorless control is applied to direct drive applications with great expectations. As

K. Ide; H. Iura; M. Inazumi

2010-01-01

110

An analytical formula for the back emf of a slotted BLDG motor  

Microsoft Academic Search

The paper presents a completely analytical formula to determine the phase back emf of a slotted BLDC motor with interior or exterior rotor and parallel or radial permanent magnet (PM) magnetization and concentrated winding. The formula is based on integration of an analytical solution for the PM magnetic field in the motor air gap. Six combination of the number of

Miroslav Markovic; Y. Perriard

2007-01-01

111

Response from a MARKAL technology model to the EMF scenario assumptions  

Microsoft Academic Search

This paper describes the modelling effort and analysis undertaken at ECN Policy Studies in the EMF-19 framework by using the Western European MARKAL model. The model structure and the advanced economic feed back formulation used is briefly described. Scenarios introducing carbon emissions reduction targets (by concentration level or by carbon taxes) lead to changes in energy mix, in technology deployment

Koen E. L. Smekens-Ramirez Morales

2004-01-01

112

SCHEME FOR INCORPORATING DC MAGNETIC FIELDS INTO EPIDEMIOLOGICAL STUDIES OF EMF EXPOSURE  

EPA Science Inventory

Experimental data on calcium-ion release in chicken brain tissue suggest that biological effects of electric and magnetic fields (EMFs) are concentrated at certain combinations of DC magnetic field strength and "critical" AC magnetic field frequencies. e hypothesize that "active"...

113

Universal "Imaginary Closed Circuit Method" and Formula for Determination of Direction of Induced EMF/Current  

ERIC Educational Resources Information Center

|Fleming's right-hand rule and the right-flat-hand rule are generally applied for determining the direction of flow of induced emf/current in straight conductors. The right-hand-fingers rule is applied for coils only. The right-hand-thumb rule can be applied for either straight conductors or coils. Different rules have to be applied for different

Atram, Dattatraya Balaram

2011-01-01

114

Absolute Realizability of Predicate Formulas  

NASA Astrophysics Data System (ADS)

The concept of an absolutely realizable predicate formula is introduced. It can be regarded as a certain refinement of the concept of a constructively generally valid formula in predicate logic. It is proved that the class of all absolutely realizable formulas is a \\Pi^1_1-complete set.Bibliography: 16 titles.

Plisko, V. E.

1984-04-01

115

Absolute Identification by Relative Judgment  

ERIC Educational Resources Information Center

In unidimensional absolute identification tasks, participants identify stimuli that vary along a single dimension. Performance is surprisingly poor compared with discrimination of the same stimuli. Existing models assume that identification is achieved using long-term representations of absolute magnitudes. The authors propose an alternative

Stewart, Neil; Brown, Gordon D. A.; Chater, Nick

2005-01-01

116

Motion Parallax and Absolute Distance.  

National Technical Information Service (NTIS)

The accuracy of absolute distance estimation based on monocular motion parallax was determined both before and after specific training. With the usual distance information eliminated, subjects either held their heads stationary or rhythmically rotated the...

S. H. Ferris

1971-01-01

117

Distribution of antibodies against Coxsackie B viruses, arboviruses and Toxoplasma gondii among patients with endomyocardial fibrosis (EMF) compared with normal subjects from EMF endemic and non-endemic zones of Nigeria.  

PubMed

The sera of eight endomyocardial fibrosis (EMF) subjects, 11 siblings of one of them and 16 normal children matched with the EMF patients for age, sex and socio-economic status from Ogunmakin and Shao/Oloru communities (eight each), situated in EMF-endemic and non-endemic areas of Nigeria respectively, were examined for the presence of antibodies against Coxsackie viruses B1-6, 16 arboviruses and Toxoplasma gondii. Sera from 36 other randomly selected normal children from Ogunmakin and 26 other randomly selected children from Shao/Oloru were also tested for the presence of antibodies against Toxoplasma gondii and the 16 arboviruses. None of the eight EMF subjects nor the 11 siblings of one of them had antibodies against any of the Coxsackie viruses B1-6 in their sera. Two of the 16 matched control subjects, one from each community, had positive antibodies, at equivocal titres against Coxsackie B1 (Ogunmakin) and B4 (Shao/Oloru). There was no significant difference in the distribution of antibody titres to the arboviruses between the EMF patients and matched controls. Normal children from the Shao/Oloru community had higher percentage antibody reactions and higher titres to the arboviruses compared with the children from Ogunmakin. All the eight EMF patients had high antibody titres against Toxoplasma gondii. Seven (87.5%) of the matched controls from Ogunmakin were sero-positive for Toxoplasma gondii compared with three (37.5%) of the matched controls from Shao/Oloru. Of the 36 normal children from Ogunmakin, 32 (88.9%) were sero-positive compared with 11 (42.3%) of the 26 normal children from Shao/Oloru. Four (36.4%) of the 11 siblings of one of the EMF patients had weak sero-positivity. It is therefore concluded that further studies are needed to clarify the role, if any, of Toxoplasma gondii in EMF. PMID:2165348

Ijaola, O; Falase, A O

1990-06-01

118

Direct Observation of the Turbulent emf and Transport of Magnetic Field in a Liquid Sodium Experiment  

NASA Astrophysics Data System (ADS)

For the first time, we have directly measured the transport of a vector magnetic field by isotropic turbulence in a high Reynolds number liquid metal flow. In analogy with direct measurements of the turbulent Reynolds stress (turbulent viscosity) that governs momentum transport, we have measured the turbulent electromotive force (emf) by simultaneously measuring three components of velocity and magnetic fields, and computed the correlations that lead to mean-field current generation. Furthermore, we show that this turbulent emf tends to oppose and cancel out the local current, acting to increase the effective resistivity of the medium, i.e., it acts as an enhanced magnetic diffusivity. This has important implications for turbulent transport in astrophysical objects, particularly in dynamos and accretion disks.

Rahbarnia, Kian; Brown, Benjamin P.; Clark, Mike M.; Kaplan, Elliot J.; Nornberg, Mark D.; Rasmus, Alex M.; Zane Taylor, Nicholas; Forest, Cary B.; Jenko, Frank; Limone, Angelo; Pinton, Jean-Franois; Plihon, Nicolas; Verhille, Gautier

2012-11-01

119

EMF measurements on the Li-Al\\/NiS couple in molten salt electrolytes  

Microsoft Academic Search

The (emf) vs. temperature curve for the Li-Al\\/NiS couple was determined in 58.2 mol percen (m\\/o) LiCl-41.8 m\\/o KCl (eutectic electrolyte), 49.1 m\\/o LiCl-50.9 m\\/o KCl (KCl-rich electrolyte), 69.6 m\\/o LiCl-30.4 m\\/o KCl (LiCl-rich electrolyte), and in 22 m\\/o Lif-31 m\\/o LiCl-47 m\\/o LiBr electrolyte. The results indicate that with these electrolytes the emf value of the couple at a

Z. Tomczuk; L. Redey; D. R. Vissers

1983-01-01

120

Standard gibbs energies of formation of the carbides of manganese by emf measurements  

NASA Astrophysics Data System (ADS)

The standard Gibbs energies of formation of Mn7C3, Mn5C2, Mn15C4, and Mn23C6 have been obtained from emf measurements using galvanic cells of the type (-)Mn, MnF2, CaF2//CaF2//CaF2, MnF2, Mn-C(+) The measurements have been carried out in the temperature range 909 to 1247 K. In the case of measurements with Mn-C alloy containing 12.9 wt pct C (Mn7C3-C two-phase region at room temperature), the slope change in the emf-temperature curve at 1181 K suggests the formation of a hitherto unidentified phase above this temperature.

Sichen, Du; Seetharaman, S.; Staffansson, L.-I.

1988-12-01

121

Application of sliding mode observer for induced e.m.f., position and speed estimation of permanent magnet motors  

Microsoft Academic Search

This paper presents a method for speed, position and induced e.m.f. estimation in permanent magnet synchronous machines (PMSM) through application of the sliding mode technique. The electrical dynamic equations of a PMSM are modified to obtain the sliding mode observer model where the induced e.m.f., position and speed are estimated using measured stator currents and voltages. The observer of the

Z. M. A. Peixo; F. M. Freitas Sa; P. F. Seixas; B. R. Menezes; P. C. Cortizo; W. S. Lacerda

1995-01-01

122

Minimization of torque pulsations in a trapezoidal back-EMF permanent magnet brushless DC motor  

Microsoft Academic Search

This paper discusses the different methods used to reduce the torque pulsations (i.e. cogging torque and torque ripple) in a trapezoidal back-EMF permanent magnet (PM) brushless DC motor. The paper covers the design options to reduce both cogging torque and torque ripple. The effect of stator ampere-turns, the influence of rotor magnetization and the effect of the processing of electrical

Sunil Murthy; Benoit Derouane; Buyun Liu; Tomy Sebastian

1999-01-01

123

Sensorless control of ultrahigh-speed PM brushless motor using PLL and third harmonic back EMF  

Microsoft Academic Search

Application-specific integrated circuit (ASIC) ML4425 is often used for sensorless control of permanent-magnet (PM) brushless direct current (BLDC) motor drives. It integrates the terminal voltage of the unenergized winding that contains the back electromotive force (EMF) information and uses a phase-locked loop (PLL) to determine the proper commutation sequence for the BLDC motor. However, even without pulsewidth modulation, the terminal

J. X. Shen; S. Iwasaki

2006-01-01

124

New thermodynamic data for liquid aluminum-magnesium alloys from emf, vapor pressures, and calorimetric studies  

Microsoft Academic Search

Experimental thermodynamic studies of liquid Al-Mg alloys have been performed by several methods resulting in: (1) Mg activities\\u000a from galvanic cells with liquid electrolytes at temperatures from 910 to 1070 K, atX\\u000a Mg = 0.1 to 0.7 and for the dilute range whenX\\u000a Mg = 0.0126 to 0.1430 at 927 K; (2) Mg activities from the emf method with solid

Z. Moser; W. Zakulski; K. Rzyman; W. Gasior; Z. Panek; I. Katayama; T. Matsuda; Y. Fukuda; T. Iida; Z. Zajaczkowski; J. Botor

1998-01-01

125

Study of Mn activities in MnNiC alloys by EMF measurements  

Microsoft Academic Search

The activities of manganese in MnNiC alloys have been studied by solid-state galvanic cell technique with CaF2 as the solid electrolyte. The measurements of electromotive force (EMF) have been carried out in the temperature range 9201240 K. The main phase compositions of the alloys have been analyzed by X-ray diffraction (XRD). It was established that the substitution of Mn by

Lidong Teng; Ragnhild Aune; Seshadri Seetharaman

2003-01-01

126

New Thermodynamic Data for Liquid Aluminum-Magnesium Alloys from emf, Vapor Pressures, and Calorimetric Studies  

Microsoft Academic Search

Experimental thermodynamic studies of liquid Al-Mg alloys have been performed by several methods resulting in: (1) Mg activities\\u000a from galvanic cells with liquid electrolytes at temperatures from\\u000a 910 to 1070 K, at XMg = 0.1 to 0.7 and for the dilute range when XMg = 0.0126 to 0.1430 at 927 K; (2) Mg activities from the emf method with solid

Z. Moser; W. Zakulski; K. Rzyman; W. Gasior; Z. Panek; I. Katayama; T. Matsuda; Y. Fukuda; T. Iida; Z. Zajaczkowski; J. Botor

1998-01-01

127

Direct Torque Control of Brushless DC Motor with Non-sinusoidal Back-EMF  

Microsoft Academic Search

In this paper, a direct torque control (DTC) technique for brushless dc (BLDC) motors with non-sinusoidal back-EMF operating in the constant torque region is presented. This approach introduces a two-phase conduction mode as opposed to the conventional three-phase DTC drives. In this control scheme, only two phases conduct at any instant of time. Unlike conventional six-step PWM current control, by

Salih Baris Ozturk; H. A. Toliyat

2007-01-01

128

Risk governance for mobile phones, power lines, and other EMF technologies.  

PubMed

Power-frequency electric and magnetic fields (EMFs) have been present in industrialized countries since the late 19th century and a considerable amount of knowledge has been accumulated as to potential health effects. The mainstream scientific view is that even if there is a risk, it is unlikely to be of major public-health significance. EMFs from cellular communications and other radio-frequency technologies have increased rapidly in the last decade. This technology is constantly changing, which makes continued research both more urgent and more challenging. While there are no persuasive data suggesting a health risk, research and particularly exposure assessment is still immature. The principal risk-governance issue with power frequencies is how to respond to weak and uncertain scientific evidence that nonetheless causes public concern. For radio-frequency electromagnetic fields, the issue is how to respond to large potential consequences and large public concern where only limited scientific evidence exists. We survey these issues and identify deficits in risk governance. Deficits in problem framing include both overstatement and understatement of the scientific evidence and of the consequences of taking protective measures, limited ability to detect early warnings of risk, and attempted reassurance that has sometimes been counterproductive. Other deficits relate to the limited public involvement mechanisms, and flaws in the identification and evaluation of tradeoffs in the selection of appropriate management strategies. We conclude that risk management of EMFs has certainly not been perfect, but for power frequencies it has evolved and now displays many successful features. Lessons from the power-frequency experience can benefit risk governance of the radio-frequency EMFs and other emerging technologies. PMID:20723143

Kheifets, Leeka; Swanson, John; Kandel, Shaiela; Malloy, Timothy F

2010-10-01

129

Non-thermal effects of EMF upon the mammalian brain: the Lund experience  

Microsoft Academic Search

The environment in which biology exists has dramatically changed during the last decades. Life was formed during billions\\u000a of years, exposed to, and shaped by the original physical forces such as gravitation, cosmic irradiation and the terrestrial\\u000a magnetism. The existing organisms are created to function in harmony with these forces. However, in the late 19th century\\u000a mankind introduced the use

Leif G. Salford; Henrietta Nittby; Arne Brun; Gustav Grafstrm; Jacob L. Eberhardt; Lars Malmgren; Bertil R. R. Persson

2007-01-01

130

Effects of electromagnetic fields (EMF) on the chemiluminescence (CL) of murine peritoneal exudate cells  

SciTech Connect

Stimulated PEC generate microbicidal free oxygen radicals which are potentially mutagenic and possibly carcinogenic. The effects of combined alternating electric and magnetic fields on oxygen radical production were measured in this study. A Helmholtz coil and parallel plate electrodes were utilized to provide uniform field characteristics. Effects were studied at combined field frequencies of 60, 600, and 6,000 Hz. Thioglycollate-elicited PEC were exposed to EMF or placed in a far corner of the lab (controls). Following the addition of zymosan, luminol-enhanced CL was measured. No differences in CL were found for exposures to 60 Hz for 18 hr; 600 Hz for 10 hr; or 6,000 Hz for 0.75 hr. PEC exposed to 6,000 Hz for 11 hr showed a 25% increase in CL over control PEC. At 600 and 6,000 Hz, the temperature of the air and a dish of saline in the EMF apparatus was 26C, vs. 25C where the controls were kept. At 60 Hz, there was no temperature difference. These preliminary experiments indicate that under these conditions, EMF fields do not have a significant effect on this immune function.

Caren, L.D. (California State Univ., Northridge (United States))

1992-02-26

131

RF-EMF exposure of fetus and mother during magnetic resonance imaging  

NASA Astrophysics Data System (ADS)

Magnetic resonance imaging (MRI) avoids risks of genetic damage but may be associated with excess heating of body tissues. To investigate the exposure to MRI radio-frequency (RF) electromagnetic fields (EMF), low-pass and high-pass birdcage coils were simulated and the whole-body pregnant woman model SILVY used to determine local and whole-body specific absorption rates (SAR) in mother and fetus. Resonant RF-EMF of MRI devices were investigated at 0.3, 1, 1.5, 2, 3 and 4 T. Results allow extrapolation also to higher fields. They showed that local SAR in mother's trunk reaches exposure limits first. However, data show that during abdominal MRI meeting exposure limits of the mother is not sufficient to protect the fetus if limits of the general populations are applied to it. In that case fetal whole-body SAR exceeds limits by 7.4-fold. It is up to the physician and/or the ethics commission to decide upon justification for abdominal MRI of pregnant women if limits are exceeded. The results indicate the need for specifically addressing fetal exposure to EMF and elaborating general recommendations by radiation protection bodies.

Pediaditis, M.; Leitgeb, N.; Cech, R.

2008-12-01

132

EMF and public policy: Balancing interests of customers, shareholders, and the public  

SciTech Connect

Regulators and utilities will likely be under increasing pressure in the next few years, pending more conclusive evidence concerning EMF hazards, to establish standards designed to protect the public from harm and/or to protect the utility from future liability. The author noted that 3 conclusions can be drawn: (1) legislation or regulations establishing standards for exposure will not necessarily protect the utility that abides by such standards; (2) it is in the interest of both utilities and regulators to keep the public informed of all developments in the EMF area and to participate actively in research on the issue; and (3) the public may no longer be satisfied with a do nothing approach pending further evidence that EMF are harmful. The public's demand that the burden of proof be shifted to industry to ensure the safety of their products should be reflected in utility and regulators' obligations to respond to the public's demand for safe, as well as reasonably priced, electrical services.

Ross, D.J.

1991-04-01

133

Design and Strength Evaluation of Structural Joint Made by Electro-Magnetic Forming(EMF)  

NASA Astrophysics Data System (ADS)

Recently, weight reduction of vehicles has been of great interest, and consequently, the use of low-density materials in the automotive industry is increasing every year. Materials should not be substituted such a way that material of component parts is simply changed because there is a problem in achieving stiffness and strength. To achieve these requirements, the automobile should be redesigned totally. Aluminum spaceframe is rapidly being adopted as a body structure for accommodating lightness, stiffness and strength requirement. In aluminum spaceframe manufacturing, it is often required to join aluminum tube. But there are few suitable methods for joining aluminum tube, so that much interest has been focused on testing suitable joining methods. Joining by electromagnetic forming(EMF) can be useful method in joining aluminum tube, which offers some advantages compared with the conventional joining method. In this paper, joining by EMF was investigated as a pre-study for applying an automotive spaceframe. Finite element simulations and strength tests were performed to analyze the influence of geometric parameters on joint strength. Based on these results, configurations of axial joint and torque joint were suggested and guidelines for designing EMF joint were established.

Park, Young-Bae; Kim, Heon-Young; Oh, Soo-Ik

2004-06-01

134

Comparative study on electro-microfiltration (EMF) of water containing different carbon nanotubes (CNTs).  

PubMed

Disposal and penetration of carbon nanotubes (CNTs) into the environment have raised increasing concerns over the years. In this study, a laboratory scale electro-microfiltration (EMF) was used to treat water containing single wall carbon nanotubes (SWCNTs) and multi-wall carbon nanotubes (MWCNTs). The goal was to examine and compare the performance during EMF of SWCNT and MWCNT. The results showed that the initial flux was increased as the applied electrical voltage increased. At an applied pressure of 49 kPa, the final flux was comparable to pure water flux when the applied electrical field strength was greater than the critical electrical field strength (Ecritical). In addition, dissolved organic carbon (DOC) removal efficiency increased as the electrical voltage increased. Due to high convective transport of organic matter toward the membrane at 98 kPa, a decrease in DOC removal efficiency with increasing electrical field strength was observed. Overall, the fluxes and DOC removal efficiencies for EMF of SWCNT and MWCNT were not significantly different with a 95% confidence. PMID:23508148

Weng, Yu-Hsiang; Wu, Hsin-Chieh; Li, Kung-Cheh

2013-01-01

135

Accurate absolute magnitudes for Kuiper belt objects and Centaurs  

Microsoft Academic Search

Accurate absolute optical magnitude values (HV and HR) for Kuiper belt objects (KBOs) and Centaurs are becoming increasingly important as observations in other wavelengths, particularly SIRTF thermal infrared measurements, become available for large samples of objects. We present accurate HV and HR values for 90 KBOs and Centaurs, based on our published optical photometry. We find that our HV values

W. Romanishin; S. C. Tegler

2005-01-01

136

Analysis of standard reference materials by absolute INAA  

SciTech Connect

Three standard reference materials, flyash, soil, and ASI 4340 steel, were analyzed by a method of absolute instrumental neutron activation analysis (INAA). Two different light water pool-type reactors were used to produce equivalent analytical results even though the epithermal to thermal flux ratio in one reactor was higher than that in the other by a factor of two.

Heft, R.E.; Koszykowski, R.F.

1981-07-01

137

JWST Absolute Flux Calibration Plan  

NASA Astrophysics Data System (ADS)

The plan for the absolute flux calibration of all JWST instruments will be described. The science goal is to be able to predict the absolute flux of stars for all JWST instruments to sub-1% accuracy. A set of A0V, solar, and hot stars have been picked as a preliminary calibration sample. This calibration sample has been chosen specifically to provide at least 5 stars of each type in all the observing modes of each JWST instrument. In addition to existing Hubble and Spitzer observations, ground-based high-resolution spectroscopy will be obtained to provide strong, independent constraints on the best fitting model stellar atmospheres for each star.

Gordon, Karl D.; Bohlin, R.

2013-01-01

138

Motion parallax and absolute distance  

Microsoft Academic Search

Determined the accuracy of absolute distance estimation based on monocular motion parallax both before and after specific training. With the usual distance information eliminated, 70 Navy enlisted men either held their heads stationary or rhythmically rotated their heads about a vertical axis while judging the distance of stimuli placed 1.22-4.57 m. away. Although distance perception was poor before training, head

Steven H. Ferris

1972-01-01

139

JWST Absolute Flux Calibration Planning  

Microsoft Academic Search

The planning for the absolute flux calibration of all four JWST science instruments will be described. The main goal is to provide a uniform calibration (photometric and spectrophotometric) across all instruments using a common set of calibration stars. These stars will include white dwarfs, A0V, and solar type stars. The combination of these different types of stars will serve to

Karl D. Gordon; R. Bohlin

2011-01-01

140

Safety of high speed guided ground transportation systems. Broadband magnetic fields: Their possible role in EMF-associated bioeffects. Final report, January 1993-June 1993  

SciTech Connect

The report reviews electric and magnetic field (EMF) exposures from electrical transportation systems, including electrically powered rail and magnetic levitation (maglev). Material also covered includes research concerning biological effects of EMF exposure, with special emphasis on broad spectrum or broadband magnetic fields. A primary objective of the report was to consider, based on present knowledge, the potential for adverse health effects from maglev-associated EMF. Because maglev technology is known to generate magnetic fields at a variety of frequencies, the document addresses the broadband EMF frequency characteristics (including pulses, intermittent fields, and other transient phenomena).

Goellner, D.; Wilson, B.; Reiter, R.; Pilla, A.; Hankin, N.

1993-08-01

141

Absolute Radiometric In-Flight Validation of Mid Infrared and Thermal Infrared Data From ASTER and MODIS on the Terra Spacecraft Using the Lake Tahoe, CA\\/NV, USA, Automated Validation Site  

Microsoft Academic Search

In December 1999, the first Moderate Resolution Imaging Spectroradiometer (MODIS) instrument and an Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument were launched into polar orbit on the Terra spacecraft. Both instruments measure surface radiance, which requires that they are calibrated and validated in flight. In-flight validation is essential to independently verify that instrument calibration correctly compensates for any

Simon J. Hook; R. Greg Vaughan; Hideyuki Tonooka; S. Geoffrey Schladow

2007-01-01

142

Photo-EMF sensitivity of porous silicon thin layer-crystalline silicon heterojunction to ammonia adsorption.  

PubMed

A new method of using photo-electromotive force in detecting gas and controlling sensitivity is proposed. Photo-electromotive force on the heterojunction between porous silicon thin layer and crystalline silicon wafer depends on the concentration of ammonia in the measurement chamber. A porous silicon thin layer was formed by electrochemical etching on p-type silicon wafer. A gas and light transparent electrical contact was manufactured to this porous layer. Photo-EMF sensitivity corresponding to ammonia concentration in the range from 10 ppm to 1,000 ppm can be maximized by controlling the intensity of illumination light. PMID:22319353

Vashpanov, Yuriy; Jung, Jae Il; Kwack, Kae Dal

2011-01-25

143

Standard gibbs energies of formation of the carbides of chromium by emf measurements  

Microsoft Academic Search

The standard Gibbs energies of formation of Cr3C2, Cr7C3, and Cr23C6 have been determined by electromotive force (emf) measurements using galvanic cells of the type (?) Cr, CrF2, CaF2 \\/\\/ CaF2 \\/\\/ CaF2, CrF2, Cr?C (+)\\u000a \\u000a The measurements have been carried out in the temperature range 1002 to 1176 K. The ?G? values obtained in the present work are generally

Du Sichen; S. Sheetharaman; L.-I. Staffansson

1989-01-01

144

Standard gibbs energies of formation of the carbides of manganese by emf measurements  

Microsoft Academic Search

The standard Gibbs energies of formation of Mn7C3, Mn5C2, Mn15C4, and Mn23C6 have been obtained from emf measurements using galvanic cells of the type (-)Mn, MnF2, CaF2\\/\\/CaF2\\/\\/CaF2, MnF2, Mn-C(+) The measurements have been carried out in the temperature range 909 to 1247 K. In the case of measurements with\\u000a Mn-C alloy containing 12.9 wt pct C (Mn7C3-C two-phase region at

Du Sichen; S. Seetharaman; L.-I. Staffansson

1988-01-01

145

Entropy equation and absolute temperature  

Microsoft Academic Search

In this paper we consider the equivalence between the heat and the entropy balance laws. These two equations are related by\\u000a an integrating factor, which defines the absolute temperature. This result is obtained applying the thermodynamic laws to\\u000a a perfect fluid. So that, by means of the entropy equation we introduce the Second Law of Thermodynamics. Two particular cases\\u000a of

Giovambattista Amendola; Carlo Banfi; Mauro Fabrizio

2010-01-01

146

Least Absolute Relative Error Estimation  

PubMed Central

Multiplicative regression model or accelerated failure time model, which becomes linear regression model after logarithmic transformation, is useful in analyzing data with positive responses, such as stock prices or life times, that are particularly common in economic/financial or biomedical studies. Least squares or least absolute deviation are among the most widely used criterions in statistical estimation for linear regression model. However, in many practical applications, especially in treating, for example, stock price data, the size of relative error, rather than that of error itself, is the central concern of the practitioners. This paper offers an alternative to the traditional estimation methods by considering minimizing the least absolute relative errors for multiplicative regression models. We prove consistency and asymptotic normality and provide an inference approach via random weighting. We also specify the error distribution, with which the proposed least absolute relative errors estimation is efficient. Supportive evidence is shown in simulation studies. Application is illustrated in an analysis of stock returns in Hong Kong Stock Exchange.

CHEN, Kani; GUO, Shaojun; YING, Zhiliang

2013-01-01

147

Genotoxic effects of exposure to radiofrequency electromagnetic fields (RF-EMF) in HL-60 cells are not reproducible.  

PubMed

Conflicting results have been published regarding the induction of genotoxic effects by exposure to radiofrequency electromagnetic fields (RF-EMF). Various results indicating a genotoxic potential of RF-EMF were reported by the collaborative EU-funded REFLEX (Risk Evaluation of Potential Environmental Hazards From Low Energy Electromagnetic Field Exposure Using Sensitive in vitro Methods) project. There has been a long-lasting scientific debate about the reliability of the reported results and an attempt to reproduce parts of the results obtained with human fibroblasts failed. Another part of the REFLEX study was performed in Berlin with the human lymphoblastoid cell line HL-60; genotoxic effects of RF-EMF were measured by means of the comet assay and the micronucleus test. The plausibility and reliability of these results were also questioned. In order to contribute to a clarification of the biological significance of the reported findings, a repeat study was performed, involving scientists of the original study. Comet-assay experiments and micronucleus tests were performed under the same experimental conditions that had led to genotoxic effects in the REFLEX study. Here we report that the attempts to reproduce the induction of genotoxic effects by RF-EMF in HL-60 cells failed. No genotoxic effects of RF-EMF were measured in the repeat experiments. We could not find an explanation for the conflicting results. However, the negative repeat experiments suggest that the biological significance of genotoxic effects of RF-EMF reported by the REFLEX study should be re-assessed. PMID:23817106

Speit, Gnter; Gminski, Richard; Tauber, Rudolf

2013-06-28

148

Effects of high frequency electromagnetic field (EMF) emitted by mobile phones on the human motor cortex.  

PubMed

We investigated whether the pulsed high frequency electromagnetic field (EMF) emitted by a mobile phone has short term effects on the human motor cortex. We measured motor evoked potentials (MEPs) elicited by single pulse transcranial magnetic stimulation (TMS), before and after mobile phone exposure (active and sham) in 10 normal volunteers. Three sites were stimulated (motor cortex (CTX), brainstem (BST) and spinal nerve (Sp)). The short interval intracortical inhibition (SICI) of the motor cortex reflecting GABAergic interneuronal function was also studied by paired pulse TMS method. MEPs to single pulse TMS were also recorded in two patients with multiple sclerosis showing temperature dependent neurological symptoms (hot bath effect). Neither MEPs to single pulse TMS nor the SICI was affected by 30 min of EMF exposure from mobile phones or sham exposure. In two MS patients, mobile phone exposure had no effect on any parameters of MEPs even though conduction block occurred at the corticospinal tracts after taking a bath. As far as available methods are concerned, we did not detect any short-term effects of 30 min mobile phone exposure on the human motor cortical output neurons or interneurons even though we can not exclude the possibility that we failed to detect some mild effects due to a small sample size in the present study. This is the first study of MEPs after electromagnetic exposure from a mobile phone in neurological patients. PMID:17516508

Inomata-Terada, Satomi; Okabe, Shingo; Arai, Noritoshi; Hanajima, Ritsuko; Terao, Yasuo; Frubayashi, Toshiaki; Ugawa, Yoshikazu

2007-10-01

149

EMF changes of Pt\\/Pd thermocouples in the range from 420\\/spl deg\\/C to 1080\\/spl deg\\/C  

Microsoft Academic Search

Drifts in EMF of Pt\\/Pd thermocouples at Cu, Ag, Al and Zn freezing points were measured. Different heat treatments were applied to thermocouples before the calibrations. The measured results showed that large emf changes appeared at Cu and Ag freezing points, and the magnitude of the drift and inhomogeneity were dependent on the final step of the heat treatment method.

Hideki Ogura; Haruhiko Numajiri; Hirokazu Narushima; Masaya Izuchi; Masaru Arai

2003-01-01

150

Absolute calibration of optical tweezers  

SciTech Connect

As a step toward absolute calibration of optical tweezers, a first-principles theory of trapping forces with no adjustable parameters, corrected for spherical aberration, is experimentally tested. Employing two very different setups, we find generally very good agreement for the transverse trap stiffness as a function of microsphere radius for a broad range of radii, including the values employed in practice, and at different sample chamber depths. The domain of validity of the WKB ('geometrical optics') approximation to the theory is verified. Theoretical predictions for the trapping threshold, peak position, depth variation, multiple equilibria, and 'jump' effects are also confirmed.

Viana, N.B.; Mazolli, A.; Maia Neto, P.A.; Nussenzveig, H.M.; Rocha, M.S.; Mesquita, O.N. [LPO-COPEA and Instituto de Fisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590 (Brazil); Departamento de Fisica, Instituto de Ciencias ExatasUniversidade Federal de Minas Gerais, Belo Horizonte, MG, 30123-970 (Brazil)

2006-03-27

151

Absolute Gravity Changes In Alaska  

NASA Astrophysics Data System (ADS)

Visco-elastic deformation models such as that of Soldati et al. [1999] predict time varying gravity signals associated with post-seismic deformation following the 1964 Prince William Sound earthquake (Mw=9.2). The rates of change are a function of the upper mantle viscosity. Aseismic creep is also a candidate mechanism for the deformation. The models differ in the spatial distribution of gravity changes; visco-elastic signals span a much larger region. Previous absolute gravity measurements have been made in Fairbanks, Alaska and Palmer, Alaska, during 1990-1991. Estimated uncertainties are in the 3-5 uGal range Visco-elastic gravity changes for Palmer are predicted to range from zero to tens of uGal, depending on the model viscosity and thickness parameters. New absolute gravity measurements at these sites are scheduled for September 2001, with 2 uGal estimated uncertainty. We hope to present initial results of the new measurements, with discussion of their implications for model testing. Different time series and instruments will be merged, and necessary corrections will be discussed

Sasagawa, G. S.

2001-12-01

152

Speed control of permanent magnet motors using sliding mode observers for induced EMF position and speed estimation  

Microsoft Academic Search

This paper presents a speed control system for a permanent magnet synchronous motor (PMSM) in which the sliding mode technique is used to estimate the induced EMF, rotor position and speed. The electrical dynamic equations of PMSM are modified to obtain the sliding mode observer model and then the variables are estimated by using only measured stator currents and voltages.

Zelia M. A. Peixoto; Flavia M. F. Sa; P. F. Seixas; Benjamin R. Menezes; Porfirio C. Cortizo

1995-01-01

153

Method of analyzing multiparameter information during the harmonic analysis of the emf of an eddy-current sensor \\/transducer  

Microsoft Academic Search

Arrangements for 'tuning out' interfering factors in the analysis of multidimensional information, expressed as a spectrum comprising the higher harmonics of the secondary emf in an eddy-current sensor (transducer), are described. The possibility of increasing accuracy in the estimation of any desired parameter is established. The necessary conditions for determining the suitability of the detuning channel and for solving systems

Iu. I. Lugovets; G. M. Kurakin

1975-01-01

154

EHS subjects do not perceive RF EMF emitted from smart phones better than non-EHS subjects.  

PubMed

As the use of smart phones increases, social concerns have arisen concerning the possible effects of radio frequency-electromagnetic fields (RF-EMFs) emitted from wideband code division multiple access (WCDMA) mobile phones on human health. The number of people with self-reported electromagnetic hypersensitivity (EHS) who complain of various subjective symptoms, such as headache, insomnia, etc., has also recently increased. However, it is unclear whether EHS subjects can detect RF-EMFs exposure or not. In this double-blind study, two volunteer groups of 17 EHS and 20 non-EHS subjects were investigated in regards to their perception of RF-EMFs with real and sham exposure sessions. Experiments were conducted using a WCDMA module inside a dummy phone with an average power of 24 dBm at 1950 MHz and a specific absorption rate of 1.57 W/kg using a dummy headphone for 32 min. In conclusion, there was no indication that EHS subjects perceive RF-EMFs better than non-EHS subjects. PMID:23366357

Kwon, Min Kyung; Kim, Sung Kean; Koo, Jeong Mo; Choi, Joon Yul; Kim, Deok Won

2012-01-01

155

Bounded variation, absolute continuity and absolute integrability for fuzzy-number-valued functions  

Microsoft Academic Search

In this paper, the concepts of bounded variation and absolute continuity for the fuzzy-number-valued functions are presented and discussed by means of the representation of the absolute value for fuzzy numbers. The relations among bounded variation, absolute continuity, Kaleva's integral and fuzzy Henstock integral are characterized. Especially, the representation of absolute continuous fuzzy valued functions is given by Henstock (Kaleva)

Zengtai Gong; Wu Congxin

2002-01-01

156

Absolute configuration of xerophenone A.  

PubMed

The title compound, C(33)H(42)O(5), known as xerophenone A {systematic name: (1R,3R,4R,6S,8E,10R)-10-hy-droxy-8-[hy-droxy(phen-yl)methyl-ene]-4-methyl-1,6-bis-(3-methyl-but-2-en-1-yl)-3-(3-methyl-but-3-en-1-yl)-11-oxatricyclo-[4.3.1.1(4,10)]undecane-7,9-dione} is a naturally occurring rearranged benzophenone compound which was isolated from the twigs of Garcinia propinqua. The absolute configuration was determined by refining the Flack parameter to 0.18?(16). The absolute configurations at positions 1, 3, 4, 6 and 10 of the xerophenone A are R, R, R, S and R. In the mol-ecule, the cyclo-hexane-1,3-dione, tetra-hydro-2H-pyran and tetra-hydro-furan rings adopt twisted boat, standard chair and envelope conformations, respectively. The 3-methyl-but-3-en-1-yl substituent is disordered over two sets of sites in a 0.771?(11):0.229?(11) ratio. An intra-molecular O-H?O hydrogen bond generates an S(6) ring motif. In the crystal, mol-ecules are linked by O-H?O and weak C-H?O inter-actions into a chain along the a axis. A very weak C-H?? inter-action and C?O short contact [2.989?(2)?] are also present. PMID:22590330

Fun, Hoong-Kun; Tantapakul, Cholpisut; Laphookhieo, Surat; Boonnak, Nawong; Chantrapromma, Suchada

2012-04-21

157

Absolute configuration of xerophenone A  

PubMed Central

The title compound, C33H42O5, known as xerophenone A {systematic name: (1R,3R,4R,6S,8E,10R)-10-hydroxy-8-[hydroxy(phenyl)methylene]-4-methyl-1,6-bis(3-methylbut-2-en-1-yl)-3-(3-methylbut-3-en-1-yl)-11-oxatricyclo[4.3.1.14,10]undecane-7,9-dione} is a naturally occurring rearranged benzophenone compound which was isolated from the twigs of Garcinia propinqua. The absolute configuration was determined by refining the Flack parameter to 0.18?(16). The absolute configurations at positions 1, 3, 4, 6 and 10 of the xerophenone A are R, R, R, S and R. In the molecule, the cyclohexane-1,3-dione, tetrahydro-2H-pyran and tetrahydrofuran rings adopt twisted boat, standard chair and envelope conformations, respectively. The 3-methylbut-3-en-1-yl substituent is disordered over two sets of sites in a 0.771?(11):0.229?(11) ratio. An intramolecular OH?O hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked by OH?O and weak CH?O interactions into a chain along the a axis. A very weak CH?? interaction and C?O short contact [2.989?(2)?] are also present.

Fun, Hoong-Kun; Tantapakul, Cholpisut; Laphookhieo, Surat; Boonnak, Nawong; Chantrapromma, Suchada

2012-01-01

158

Thermodynamic studies on chromium carbides by the electromotive force (emf) method  

Microsoft Academic Search

The Gibbs energies of formation ?fG of the three carbides Cr3C2, Cr7C3 and Cr23C6 existing in the CrC system were re-determined by electromotive force (emf) measurements between 930 and 1120 K using the galvanic cells Cr, CrF2?CaF2?CrF2, CrmCn, CrpCq which give at 1100 K: ?fG ?Cr3C2?=?84.3 kJ\\/mol, ?fG ?Cr7C3?=?177 kJ\\/mol and ?fG ?Cr23C6?=?407 kJ\\/mol. The third-law enthalpies of formation ?fH

Heiko Kleykamp

2001-01-01

159

OPC model prediction capability improvements by accounting for mask 3D-EMF effects  

NASA Astrophysics Data System (ADS)

As mask feature sizes have shrunk well below the exposure wavelength, the thin mask of Kirchhoff approximation breaks down and 3D mask effects contribute significantly to the through-focus CD behavior of specific features. While full-chip rigorous 3D mask modeling is not computationally feasible, approximate simulation methods do enable the 3D mask effects to be represented. The use of such approximations improves model prediction capability. This paper will look at a 28nm darkfield and brightfield layer datasets that were calibrated with a Kirchhoff model and with two different 3D-EMF models. Both model calibration accuracy and verification fitness improvements are realized with the use of 3D models.

Cheng, Jacky; Schramm, Jessy; Zhang, Dong Qing; Foong, Yee Mei; Zuniga, Christian; Do, Thuy; Tejnil, Edita; Sturtevant, John; Chung, Angeline; Jantzen, Kenneth

2012-03-01

160

Cadmium activities of silver-cadmium alloys determined from measurements on emf cells involving displacement reactions  

SciTech Connect

Cadmium activities have been obtained for dilute solutions of silver in cadmium at 776 K from emf measurements using the cell: W-Cd/CdI' + Cd (A/sub Cd/ = 1) parallels CdI'' + AgI + Cd (a/sub Cd/) < 1)/Cd, Ag-W. When the displacement reaction 2Ag + CdI'' i Cd + 2AgI is taken into account, the calculated cadmium activities follow the equation a/sub Cd/ = 1 - N/sub Ab/ - 0.607 N''/sub Ag/ with a standard deviation of 0.00001 for those measurements (taken by the most precise method) used in the least squares fit. The largest deviation from the curve for all points measured was 0.0006 or 0.9 g/cal in G/sub Cd/.

Houseman, B.L.; Conant, D.R.

1984-01-01

161

Insights from EMF Associated Agricultural and Forestry Greenhouse Gas Mitigation Studies  

SciTech Connect

Integrated assessment modeling (IAM) as employed by the Energy Modeling Forum (EMF) generally involves a multi-sector appraisal of greenhouse gas emission (GHGE) mitigation alternatives and climate change effects typically at the global level. Such a multi-sector evaluation encompasses potential climate change effects and mitigative actions within the agricultural and forestry (AF) sectors. In comparison with many of the other sectors covered by IAM, the AF sectors may require somewhat different treatment due to their critical dependence upon spatially and temporally varying resource and climatic conditions. In particular, in large countries like the United States, forest production conditions vary dramatically across the landscape. For example, some areas in the southern US present conditions favorable to production of fast growing, heat tolerant pine species, while more northern regions often favor slower-growing hardwood and softwood species. Moreover, some lands are currently not suitable for forest production (e.g., the arid western plains). Similarly, in agriculture, the US has areas where citrus and cotton can be grown and other areas where barley and wheat are more suitable. This diversity across the landscape causes differential GHGE mitigation potential in the face of climatic changes and/or responses to policy or price incentives. It is difficult for a reasonably sized global IAM system to reflect the full range of sub-national geographic AF production possibilities alluded to above. AF response in the face of climate change altered temperature precipitation regimes or mitigation incentives will likely involve region-specific shifts in land use and agricultural/forest production. This chapter addresses AF sectoral responses in climate change mitigation analysis. Specifically, we draw upon US-based studies of AF GHGE mitigation possibilities that incorporate sub-national detail drawing largely on a body of studies done by the authors in association with EMF activities. We discuss characteristics of AF sectoral responses that could be incorporated in future IAM efforts in climate change policy.

McCarl, Bruce A.; Murray, Brian; Kim, Man-Keun; Lee, Heng-Chi; Sands, Ronald D.; Schneider, Uwe

2007-11-19

162

Lack of an EMF-induced genotoxic effect in the Ames assay  

SciTech Connect

A few epidemiological studies have linked exposure to electromagnetic fields (EMF) and the incidence of cancer. Since many carcinogens are mutagens in the Ames assay, the purpose of this study was to determine if exposure of four tester strains of Salmonella typhimurium (TA97a, TA98, TA100, and TA102) to EMF would increase their rate of mutation. Parallel plate electrodes and Helmholtz coils were used to create uniform field properties 300 coils were used to create uniform field properties (300 V/in., 0.3 mT). Separate and combined alternating electric and magnetic fields effects were studied at a combined field frequency of 60, 600, and 6000 Hz at room temperature. These fields did not elevate the temperature of the culture plates above room temperature. Petri dishes containing each tester strain in top agar were exposed to an electric field (E), magnetic field (M), combined electric and magnetic field (EM), or no additional field above ambient conditions in the lab (control). Four plates containing each strain were exposed in each condition: two plates had the appropriate positive-control mutagen for each strain included in the top agar and two plates did not. Plates were exposed to either E, M, EM, or control conditions at room temperature for 48 hr. and then incubated an additional 24 hr. at 37 deg. C. The plates containing mutagen in the top agar showed an increased number of colonies consistent with mutagenesis. However, the rate of mutation in the S. Typhimurium strains TA97a, TA98, TA100, and TA102 in either the presence or absence of mutagen was not affected by 48 hr. exposure at room temperature to E, M, or EM fields at 60, 600, 94 6000 Hz. 24 refs., 1 fig., 3 tabs.

Morandi, M.A.; Pak, C.M.; Caren, R.P.; Caren, L.D. [California State Univ., Northridge, CA (United States)

1996-12-31

163

Hereditarily Unicoherent Continua and Their Absolute Retracts  

Microsoft Academic Search

We investigate absolute retracts for classes of hereditarily unicoherent continua, tree-like continua, ?- dendroids, dendroids and some other related ones. The main results are: (1) the inverse limits of trees with confluent bond- ing mappings are absolute retracts of hereditarily unicoherent continua; (2) each tree-like continuum is embeddable in a spe- cial way in a tree-like absolute retract for the

Janusz J. Charatonik; W? odzimierz J. Charatonik; Janusz R. Prajs

2004-01-01

164

Measurement of Absolute Magnetic Moment  

NASA Astrophysics Data System (ADS)

In the past NIST has issued a number of magnetic moment and magnetic susceptibility standards. One of the most popular has been the Ni magnetic moment standard in the form a 2.38 mm diameter sphere of annealed, high-purity nickel, issued in 1978. However, the supply of all the magnetic standards has been exhausted for several years now and the equipment used for their certification no longer exists. Currently, NIST is assembling a precision absolute magnetometer closely resembling the force-based system used earlier by Candela and Mundy (G.A. Candela and R.E. Mundy, Rev. Sci. Instr. 32, 1056 (1959).), but which will have improved accuracy. This magnetometer will be used to certify a new series of magnetic standards, the first of which will be a replacement nickel sphere. A sphere has the advantage that it has uniform magnetization and a known demagnetizing factor, and approximates a point dipole. Nickel has the advantage of saturation at low field, a small temperature dependence at room temperature, and a relatively small field dependence. Other standards with smaller moments and other geometries are also being considered. These, and the current state of the equipment development will be described.

Shull, R. D.; Swartzendruber, L. J.

1998-03-01

165

Absolute configuration of strictosidinic acid.  

PubMed

The absolute configuration of strictosidinic acid, (2S,3R,4S)-3-ethenyl-2-(?-D-glucopyranosyloxy)-4-{[(1S)-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-1-yl]methyl}-3,4-dihydro-2H-pyran-5-carboxylate, was determined from its sodium chloride trihydrate, poly[[diaqua((2S,3R,4S)-3-ethenyl-2-(?-D-glucopyranosyloxy)-4-{[(1S)-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-2-ium-1-yl]methyl}-3,4-dihydro-2H-pyran-5-carboxylate)sodium] chloride monohydrate], {[Na(C(26)H(32)N(2)O(9))(H(2)O)(2)]ClH(2)O}(n). The strictosidinic acid molecule participates in intermolecular hydrogen bonds of the O-H...O and O-H...Cl types. The solid-state conformation was observed as a zwitterion, based on a charged pyridine N atom and a carboxylate group, the latter mediating the packing through coordination with the sodium cation. PMID:22476143

Castro, Rosane de P; Matos, Carolina da S; do Nascimento, Cludia A; Oliveira, Ceclia M A; Kato, Luclia; Lio, Luciano M; Sabino, Jos R

2012-03-14

166

A liquid-helium-cooled absolute reference cold load for long-wavelength radiometric calibration  

Microsoft Academic Search

Design, radiometric and thermal performance, and operation of a large diameter (78 cm) liquid-helium-cooled blackbody absolute reference cold load (CL) for the calibration of microwave radiometers is described. CL provides an absolute calibration near the liquid-helium (LHe) boiling point, with total uncertainty in the radiometric temperature of less than 30 mK over the 2.5-23 cm wavelength operating range. CL was

Marc Bensadoun; Chris Witebsky; George Smoot; Giovanni de Amici; Al Kogut; Steve Levin

1992-01-01

167

Thermal electromotive force of cermet films based on borides of rare-earth metals  

SciTech Connect

The thermal emf and electrical conductivity of cermet films comprised of conducting solid solutions of europium and praseodymium borides and a dielectric glass crystalline binder were studied using a combination of temperature and voltage measurements. The dependence of these properties on temperature and the Seebeck coefficient were also determined. Results indicate that the mechanism of charge transfer in these films is ambiguous.

Islamgaliev, R.K.; Zyrin, A.V.; Shulishova, O.I.; Shcherbak, I.A.

1988-04-01

168

MSTAR: a submicrometer absolute metrology system  

NASA Astrophysics Data System (ADS)

The Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor permits absolute distance measurement with subnanometer accuracy, an improvement of 4 orders of magnitude over current techniques. The system uses fast phase modulators to resolve the integer cycle ambiguity of standard interferometers. The concept is described and demonstrated over target distances up to 1 m. The design can be extended to kilometer-scale separations.

Lay, O. P.; Dubovitsky, S.; Peters, R. D.; Burger, J. P.; Ahn, S.-W.; Steier, W. H.; Fetterman, H. R.; Chang, Y.

2003-06-01

169

What is wrong with absolute individual fitness?  

Microsoft Academic Search

One of the most basic facts about evolution is that fitness is a relative concept. It does not matter how well an organism survives and reproduces, only that it does so better than other organisms bearing alternative traits. Nevertheless, many evolutionary arguments are framed in terms of absolute individual fitness. The absolute fitness criterion (AFC) can be justified in terms

David Sloan Wilson

2004-01-01

170

Indistinguishability of absolutely continuous and singular distributions  

Microsoft Academic Search

It is shown that there are no consistent decision rules for the hypothesis testing problem of distinguishing between absolutely continuous and purely singular probability distributions on the real line. In fact, there are no consistent decision rules for distinguishing between absolutely continuous distributions and distributions supported by Borel sets of Hausdorff dimension 0. It follows that there is no consistent

Steven P. Lalley; Andrew Nobel

2003-01-01

171

Absolute fission rates in the FFTF  

Microsoft Academic Search

The part of the FFTF Reactor Characterization Program reported in this paper is a measurement of absolute fission rates of eight major fuel isotopes at two different positions within the reactor. The instruments employed in these tests were fission ionization chambers for which the absolute efficiency and fissionable deposit mass assay have been rigorously established.

D. M. Gilliam; J. L. Fuller; J. A. Grundl; J. A. Rawlins; J. W. Daughtry

1981-01-01

172

Absolute Income, Relative Income, and Happiness  

ERIC Educational Resources Information Center

|This paper uses data from the World Values Survey to investigate how an individual's self-reported happiness is related to (i) the level of her income in absolute terms, and (ii) the level of her income relative to other people in her country. The main findings are that (i) both absolute and relative income are positively and significantly

Ball, Richard; Chernova, Kateryna

2008-01-01

173

Using model organism Saccharomyces cerevisiae to evaluate the effects of ELF-MF and RF-EMF exposure on global gene expression.  

PubMed

The potential health hazard of exposure to electromagnetic fields (EMF) continues to cause public concern. However, the possibility of biological and health effects of exposure to EMF remains controversial and their biophysical mechanisms are unknown. In the present study, we used Saccharomyces cerevisiae to identify genes responding to extremely low frequency magnetic fields (ELF-MF) and to radiofrequency EMF (RF-EMF) exposures. The yeast cells were exposed for 6?h to either 0.4?mT 50?Hz ELF-MF or 1800?MHz RF-EMF at a specific absorption rate of 4.7?W/kg. Gene expression was analyzed by microarray screening and confirmed using real-time reverse transcription-polymerase chain reaction (RT-PCR). We were unable to confirm microarray-detected changes in three of the ELF-MF responsive candidate genes using RT-PCR (P?>?0.05). On the other hand, out of the 40 potential RF-EMF responsive genes, only the expressions of structural maintenance of chromosomes 3 (SMC3) and aquaporin 2 (AQY2 (m)) were confirmed, while three other genes, that is, halotolerance protein 9 (HAL9), yet another kinase 1 (YAK1) and one function-unknown gene (open reading frame: YJL171C), showed opposite changes in expression compared to the microarray data (P?EMF is limited to only a very small number of genes. The possible biological consequences of the gene expression changes induced by RF-EMF await further investigation. PMID:22487891

Chen, Guangdi; Lu, Deqiang; Chiang, Huai; Leszczynski, Dariusz; Xu, Zhengping

2012-04-09

174

Platinum versus palladium thermocouples: an emf-temperature reference function for the range 0 C to 1500 C  

Microsoft Academic Search

We present an emf-temperature reference function for platinum versus palladium (Pt\\/Pd) thermocouples in air for the range 0 C to 1500 C. The reference function is based on the International Temperature Scale of 1990 (ITS-90) and has an expanded uncertainty (coverage factor of two) of less than the equivalent of 11 mK for temperatures up to 1050 C and rising

G W Burns; D C Ripple; M Battuello

1998-01-01

175

Design issues and estimation errors analysis of back-EMF based position and speed observer for SPM synchronous motors  

Microsoft Academic Search

A back-electromotive force (back-EMF) based sensorless technique for surface-mounted permanent magnet synchronous motor (SPMSM) drive systems is considered in this paper. The model of the observer is developed in the Laplace domain and represents an original approach with respect to state-of-art proposals, normally employing a state-state representation. This allows a more intuitive but equivalent design of the observer's gains, based

Silverio Bolognani; Sandro Calligaro; Roberto Petrella

2011-01-01

176

Intracellular Ca2+ Mobilization and Beta-hexosaminidase Release Are Not Influenced by 60 Hz-electromagnetic Fields (EMF) in RBL 2H3 Cells  

PubMed Central

The effects of extremely low frequency electromagnetic fields (EMF) on intracellular Ca2+ mobilization and cellular function in RBL 2H3 cells were investigated. Exposure to EMF (60 Hz, 0.1 or 1 mT) for 4 or 16 h did not produce any cytotoxic effects in RBL 2H3 cells. Melittin, ionomycin and thapsigargin each dose-dependently increased the intracellular Ca2+ concentration. The increase of intracellular Ca2+ induced by these three agents was not affected by exposure to EMF (60 Hz, 1 mT) for 4 or 16 h in RBL 2H3 cells. To investigate the effect of EMF on exocytosis, we measured beta-hexosaminidase release in RBL 2H3 cells. Basal release of beta-hexosaminidase was 12.32.3% in RBL 2H3 cells. Exposure to EMF (60 Hz, 0.1 or 1 mT) for 4 or 16 h did not affect the basal or 1 M melittin-induced beta-hexosaminidase release in RBL 2H3 cells. This study suggests that exposure to EMF (60 Hz, 0.1 or 1 mT), which is the limit of occupational exposure, has no influence on intracellular Ca2+ mobilization and cellular function in RBL 2H3 cells.

Hwang, Yeon Hee; Song, Ho Sun; Kim, Hee Rae; Ko, Myoung Soo; Jeong, Jae Min; Kim, Yong Ho; Ryu, Jeong Soo; Sohn, Uy Dong; Gimm, Yoon-Myoung; Myung, Sung Ho

2011-01-01

177

Synthesis and absolute configuration of (?)-chettaphanin II  

Microsoft Academic Search

An efficient synthesis of chettaphanin II has been achieved from ent-halimic acid. The absolute configuration of the natural product was established and corroborated by X-ray analysis of chettaphanin II.

I. S. Marcos; F. A. Hernndez; M. J. Sexmero; D. D??ez; P. Basabe; A. B. Pedrero; N. Garc??a; F. Sanz; J. G. Urones

2002-01-01

178

The Simplicity Argument and Absolute Morality  

ERIC Educational Resources Information Center

|In this paper the author has maintained that there is a similarity of thought to be found in the writings of Cudworth, Emerson, and Husserl in his investigation of an absolute system of morality. (Author/RK)|

Mijuskovic, Ben

1975-01-01

179

Magnifying absolute instruments for optically homogeneous regions  

SciTech Connect

We propose a class of magnifying absolute optical instruments with a positive isotropic refractive index. They create magnified stigmatic images, either virtual or real, of optically homogeneous three-dimensional spatial regions within geometrical optics.

Tyc, Tomas [Institute of Theoretical Physics and Astrophysics, Masaryk University, Kotlarska 2, CZ-61 137 Brno (Czech Republic)

2011-09-15

180

Absolute calibration technique for spontaneous fission sources  

SciTech Connect

An absolute calibration technique for a spontaneously fissioning nuclide (which involves no arbitrary parameters) allows unique determination of the detector efficiency for that nuclide, hence of the fission source strength.

Zucker, M.S.; Karpf, E.

1984-01-01

181

A New Gimmick for Assigning Absolute Configuration.  

ERIC Educational Resources Information Center

|A five-step procedure is provided to help students in making the assignment absolute configuration less bothersome. Examples for both single (2-butanol) and multi-chiral carbon (3-chloro-2-butanol) molecules are included. (JN)|

Ayorinde, F. O.

1983-01-01

182

A New Gimmick for Assigning Absolute Configuration.  

ERIC Educational Resources Information Center

A five-step procedure is provided to help students in making the assignment absolute configuration less bothersome. Examples for both single (2-butanol) and multi-chiral carbon (3-chloro-2-butanol) molecules are included. (JN)

Ayorinde, F. O.

1983-01-01

183

Sensor of Ratios of Absolute Gas Pressures.  

National Technical Information Service (NTIS)

The article describes a sensor of ratios of absolute gas pressures containing elastic sensitive elements picking up pressures and acting on a compensation spring system transmitting the force onto a tensometric converter which for the purpose of improving...

G. I. Tyukel L. A. Pletnev

1967-01-01

184

Granulocyte Kinetics after Thermal Injury.  

National Technical Information Service (NTIS)

A 30% third-degree burn in rats was used to study granulocyte kinetics after thermal injury. Early postburn leukocytosis, a result of granulocyte demargination and early bone marrow release, was followed by an absolute granulocytopenia, despite elevated c...

K. Eurenius R. O. Brouse

1972-01-01

185

MSTAR: a submicrometer absolute metrology system.  

PubMed

The Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor permits absolute distance measurement with subnanometer accuracy, an improvement of 4 orders of magnitude over current techniques. The system uses fast phase modulators to resolve the integer cycle ambiguity of standard interferometers. The concept is described and demonstrated over target distances up to 1 m. The design can be extended to kilometer-scale separations. PMID:12816236

Lay, O P; Dubovitsky, S; Peters, R D; Burger, J P; Ahn, S W; Steier, W H; Fetterman, H R; Chang, Y

2003-06-01

186

Nonlinear constraints in the absolute coordinate formulation  

Microsoft Academic Search

SummaryThe modeling of deformation in flexible multibody systems is still under intensive investigation. While the floating frame\\u000a of reference formulation has become a standard for the modeling of deformable moving bodies, formulations based on absolute\\u000a coordinates are comparatively new. The recently developed absolute nodal coordinate formulation uses solely nodal position\\u000a and slopes as degrees of freedom for structural elements. The

J. Gerstmayr

2007-01-01

187

Kelvin and the absolute temperature scale  

NASA Astrophysics Data System (ADS)

This paper describes the absolute temperature scale of Kelvin (William Thomson). Kelvin found that Carnot's axiom about heat being a conserved quantity had to be abandoned. Nevertheless, he found that Carnot's fundamental work on heat engines was correct. Using the concept of a Carnot engine Kelvin found that Q1/Q2 = T1/T2. Thermometers are not used to obtain absolute temperatures since they are calculated temperatures.

Erlichson, Herman

2001-07-01

188

Absolute Temperature Monitoring Using RF Radiometry in the MRI Scanner  

PubMed Central

Temperature detection using microwave radiometry has proven value for noninvasively measuring the absolute temperature of tissues inside the body. However, current clinical radiometers operate in the gigahertz range, which limits their depth of penetration. We have designed and built a noninvasive radiometer which operates at radio frequencies (64 MHz) with ?100-kHz bandwidth, using an external RF loop coil as a thermal detector. The core of the radiometer is an accurate impedance measurement and automatic matching circuit of 0.05 ? accuracy to compensate for any load variations. The radiometer permits temperature measurements with accuracy of 0.1K, over a tested physiological range of 28 C40 C in saline phantoms whose electric properties match those of tissue. Because 1.5 T magnetic resonance imaging (MRI) scanners also operate at 64 MHz, we demonstrate the feasibility of integrating our radiometer with an MRI scanner to monitor RF power deposition and temperature dosimetry, obtaining coarse, spatially resolved, absolute thermal maps in the physiological range. We conclude that RF radiometry offers promise as a direct, noninvasive method of monitoring tissue heating during MRI studies and thereby providing an independent means of verifying patient-safe operation. Other potential applications include titration of hyper- and hypo-therapies.

El-Sharkawy, AbdEl-Monem M.; Sotiriadis, Paul P.; Bottomley, Paul A.; Atalar, Ergin

2007-01-01

189

Absolute Temperature Monitoring Using RF Radiometry in the MRI Scanner.  

PubMed

Temperature detection using microwave radiometry has proven value for noninvasively measuring the absolute temperature of tissues inside the body. However, current clinical radiometers operate in the gigahertz range, which limits their depth of penetration. We have designed and built a noninvasive radiometer which operates at radio frequencies (64 MHz) with ?100-kHz bandwidth, using an external RF loop coil as a thermal detector. The core of the radiometer is an accurate impedance measurement and automatic matching circuit of 0.05 ? accuracy to compensate for any load variations. The radiometer permits temperature measurements with accuracy of 0.1K, over a tested physiological range of 28 C-40 C in saline phantoms whose electric properties match those of tissue. Because 1.5 T magnetic resonance imaging (MRI) scanners also operate at 64 MHz, we demonstrate the feasibility of integrating our radiometer with an MRI scanner to monitor RF power deposition and temperature dosimetry, obtaining coarse, spatially resolved, absolute thermal maps in the physiological range. We conclude that RF radiometry offers promise as a direct, noninvasive method of monitoring tissue heating during MRI studies and thereby providing an independent means of verifying patient-safe operation. Other potential applications include titration of hyper- and hypo-therapies. PMID:18026562

El-Sharkawy, Abdel-Monem M; Sotiriadis, Paul P; Bottomley, Paul A; Atalar, Ergin

2006-11-01

190

Validation of the absolute extrinsic Fabry-Perot interferometer for strain measurements  

Microsoft Academic Search

This report presents the results of experiments performed to verify the performance of the fiber-optic absolute extrinsic Fabry-Perot interferometer (AEFPI) for strain measurements. In these experiments, AEFPI sensors are surface mounted and embedded in various materials and subjected to mechanical and thermal strains. Strains measured by the AEFPI are compared to analytical predictions and to metallic foil strain gage measurements

Craig M. Lawrence; Drew V. Nelson

1995-01-01

191

New absolute magnitude calibrations for detached binaries  

NASA Astrophysics Data System (ADS)

Lutz-Kelker bias corrected absolute magnitude calibrations for the detached binary systems with main-sequence components are presented. The absolute magnitudes of the calibrator stars were derived at intrinsic colours of Johnson-Cousins and 2MASS (Two Micron All Sky Survey) photometric systems. As for the calibrator stars, 44 detached binaries were selected from the Hipparcos catalogue, which have relative observed parallax errors smaller than 15% (??/??0.15). The calibration equations which provide the corrected absolute magnitude for optical and near-infrared pass bands are valid for wide ranges of colours and absolute magnitudes: -0.18<(B-V)0<0.91, -1.6absolute magnitude calibrations of this study can be used as a convenient statistical tool to estimate the true distances of detached binaries out of Hipparcos' distance limit.

Bilir, S.; Ak, T.; Soydugan, E.; Soydugan, F.; Yaz, E.; Filiz Ak, N.; Eker, Z.; Demircan, O.; Helvaci, M.

2008-10-01

192

[Dependence of the non-thermal radiofrequency electromagnetic field bioeffects on the typological features of electroencephalogram in humans].  

PubMed

In researches with participation of volunteers bioeffects of short-term non-thermal radiofrequency electromagnetic field (RF EMF) exposure were studied. The basic form of brain's reaction was the amplification of energy in a-range in electroencephalogram (EEG) spectra. Dependence of these changes, not only due to the changes of the exposure parameters, but also due to personal EEG typological features was shown. Moderate degree of the alpha frequencies domination in the background promoted development of reaction of a brain to the RF EMF exposure. To a lesser degree it was shown at hyperactivity of this range and, practically, was absent in the conditions of theta- or beta2-range domination in the EEG background with the open and closed eyes. The combination of RF EMF exposure and monotonous activity has authentically strengthened result, keeping the basic form of reaction (energy amplification in the alpha range of EEG spectrum) and dependence on EEG typological features. PMID:21434398

Luk'ianova, S N; Grigor'ev, Iu G; Grigor'ev, O A; Merkulov, A V

193

A next-generation EMF simulator for EUV lithography based on the pseudo-spectral time-domain method  

NASA Astrophysics Data System (ADS)

The FDTD method has difficulty in modeling buried defects in multilayered EUV masks because of the limitations of grid snapping, large numerical-dispersion errors and rectangular cells that do not fit the non-planar shapes of buried defects easily. In this paper, a rigorous EMF simulator based on the pseudo-spectral time-domain (PSTD) method is discussed. The PSTD method is free from the limitations of FDTD and can model buried defects in EUV masks accurately. Detailed comparison with FDTD is given to demonstrate the accuracy, speed and memory efficiency of PSTD for the rigorous simulation of buried defects in EUV masks.

Yeung, Michael S.

2012-03-01

194

Absolute Zero: Community Education Outreach Guide  

NSDL National Science Digital Library

This guide provides curricular resources for study of the history and science of the quest for ever colder temperature. Designed for teachers and informal educators of middle school students. this guide offers hands-on demonstrations, questions to encourage student participation, suggestions for class activities, and ways to encourage students to continue studying the science. Topics include low-temperature physics and the impact of technologies such as air conditioning, refrigeration and liquefied gases. This material is related to a two-part public broadcasting special, Absolute Zero, produced by Meridian Productions and Windfall Films. Absolute Zero is underwritten by the National Science Foundation and the Alfred P. Sloan Foundation and is based largely on Tom Shachtmans acclaimed book, Absolute Zero and the Conquest of Cold.

2008-09-18

195

Molecular iodine absolute frequencies. Final report  

SciTech Connect

Fifty specified lines of {sup 127}I{sub 2} were studied by Doppler-free frequency modulation spectroscopy. For each line the classification of the molecular transition was determined, hyperfine components were identified, and one well-resolved component was selected for precise determination of its absolute frequency. In 3 cases, a nearby alternate line was selected for measurement because no well-resolved component was found for the specified line. Absolute frequency determinations were made with an estimated uncertainty of 1.1 MHz by locking a dye laser to the selected hyperfine component and measuring its wave number with a high-precision Fabry-Perot wavemeter. For each line results of the absolute measurement, the line classification, and a Doppler-free spectrum are given.

Sansonetti, C.J. [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

1990-06-25

196

Thermodynamic behavior of high-T sub c oxide systems via EMF and related measurements  

SciTech Connect

EMF measurements of oxygen fugacities as a function of stoichiometry have been made in the YBa{sub 2}Cu{sub 3}O{sub x}, and NdBa{sub 2}Cu{sub 3}O{sub x}, and Nd{sub 1.81}Ce{sub 0.19}CuO{sub x} superconducting systems in the temperature range 400--750{degree}C by means of an oxygen titration technique with an yttria-stabilized zirconia electrolyte. The object of our current measurements is to investigate the effect of ionic size of Y, Gd and Nd on the thermodynamic behavior and structural transition in the LnBa{sub 2}Cu{sub 3}O{sub x} system. The shape of the 400{degree}C isotherm for NdBa{sub 2}Cu{sub 3}O{sub x} suggests the presence of a miscibility gap at lower temperatures, at values of x that are higher than those in the YBa{sub 2}Cu{sub 3}O{sub x} system. The locations of the miscibility gaps are consistent with the effects of ionic radii on the composition dependence of {Tc} for these systems. Our results explain the two plateaus in measured value of {Tc} as a function of composition for the YBa{sub 2}Cu{sub 3}O{sub x} system and appear to be consistent with the less pronounced {Tc} plateaus found for the NdBa{sub 2}Cu{sub 3}O{sub x} system higher stoichiometry values. For a given oxygen stoichiometry, partial pressures of oxygen above NdBa{sub 2}Cu{sub 3}O{sub x} are higher than for the YBa{sub 2}Cu{sub 3}O{sub x} system in accord with calculated partial molar thermodynamic quantities. The results of limited measurements on the n-type (electron-doped) superconducting Nd{sub 1.81}Ce{sub 0.19}CuO{sub x} system will be presented. A thermodynamic assessment and intercomparison of our oxygen partial pressure measurements with the results of other measurements will be presented. 34 refs., 9 figs., 1 tab.

Tetenbaum, M.; Tumidajaski, P.; Bloom, I.D.; Brown, D.L.; Blander, M.

1991-01-01

197

Absolute distance measurement with the MSTAR sensor  

NASA Astrophysics Data System (ADS)

The MSTAR sensor (Modulation Sideband Technology for Absolute Ranging) is a new system for measuring absolute distance, capable of resolving the integer cycle ambiguity of standard intrferometers, and making it possible to measure distance with sub-nanometer accuracy. The sensor uses a single laser in conjugation with fast phase modulators and low-frequency detectors. We describe the design of the system - the principle of operation, the metrology source, beam-launching optics, and signal processing - and show results for target distance up to 1 meter. We then demonstrate how the system can be scaled to kilometer-scale distances.

Lay, Oliver P.; Dubovitsky, Serge; Peters, Robert D.; Burger, Johan; Ahn, Seh-Won; Steier, William H.; Fetterman, Harold R.; Chang, Yian

2003-11-01

198

Precise Measurement of the Absolute Fluorescence Yield  

SciTech Connect

We present preliminary results of the absolute yield of fluorescence emission in atmospheric gases. Measurements were performed at the Fermilab Test Beam Facility with a variety of beam particles and gases. Absolute calibration of the fluorescence yield to 5% level was achieved by comparison with two known light sources - the Cherenkov light emitted by the beam particles, and a calibrated nitrogen laser. The uncertainty of the energy scale of current Ultra-High Energy Cosmic Rays experiments will be significantly improved by the AIRFLY measurement.

Ave, M.; Daumiller, K.; Keilhauer, B.; Klages, H.; Salamida, F.; Smida, R. [Karlsruhe Institute of Technology, IK, Postfach 6980, D - 76021 Karlsruhe (Germany); Bohacova, M.; Nozka, L.; Palatka, M.; Ridky, J.; Schovanek, P. [Institute of Physics of the Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-182 21 Praha 8 (Czech Republic); Di Carlo, P.; Iarlori, M.; Petrera, S.; Rizi, V. [Dipartimento di Fisica dell'Universita de l'Aquila and INFN, Via Vetoio, I-67010 Coppito, Aquila (Italy); Di Giulio, C.; Verzi, V. [Dipartimento di Fisica dell'Universita di Roma Tor Vergata and Sezione INFN, Via della Ricerca Scientifica, I-00133 Roma (Italy); San Luis, P. Facal; Monasor, M.; Privitera, P. [University of Chicago, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, 5640 S. Ellis Ave., Chicago, IL 60637 (United States)

2011-09-22

199

Safety of high speed guided ground transportation systems: Review of existing EMF guidelines, standards and regulations. Final report, January-June 1993  

SciTech Connect

Although there are no maglev or other advanced high-speed rail systems currently operating in the United States, EMF exposure is still of concern as it relates top 60 hertz (Hz) power transmission and distribution lines and electrical appliances. The report provides information on existing and proposed EMF guidelines, standards and regulations at the international, national, state, and local levels. It covers fields in the frequency range of 0-100 Ghz and includes EMF exposures for both the general public and workers. Whereas the above frequency range includes radio frequencies and microwave frequencies, the main focus for the United States is on extremely low frequencies (ELF), such as those associated with the use of electric power. However, there is some discussion of regulation of higher frequency ranges in other countries.

Goellner, D.; Wilson, B.; Reiter, R.; Pilla, A.; Hankin, N.

1993-08-01

200

Setting up an off-site emergency mortuary facility (EMF) to deal with a DVI incident: disaster victim management (DVM).  

PubMed

Forensic mortuaries in all Australian jurisdictions are dealing with increasing workloads, with routine cases regularly occupying greater than 50%, and often as much as 85%, of existing cold room body storage capacity, particularly over long weekends and during seasonal increases in respiratory infections. Hence the need to deal with a sudden influx of deceased persons or multiple body parts in a mass fatality incident would overwhelm most Australian forensic mortuaries, thereby requiring other means of body storage and processing. Exercise "Construct" was a joint South Australian Police (SAPol) and Forensic Science South Australia exercise designed to practice the establishment and construction of an emergency mortuary facility (EMF) to deal with a mass fatality incident and the subsequent disaster victim identification process. The aims of the exercise were to test preparedness, activation and construction processes relative to the establishment of an EMF. The exercise provided the opportunity to identify gaps in the capacity to successfully complete the tasks within the allotted time frames. The exercise reinforced the need to have a comprehensive and clearly documented process which must include a current list of suppliers who can deliver goods and services in a timely manner. The aim of this paper is to report on the exercise findings and share the experience with other jurisdictions. It will also provide other jurisdictions with the opportunity to consider whether the South Australian model will be useful to them in improving their own response when confronted with a mass fatality incident that may overwhelm existing local mortuary capacities and capabilities. PMID:22246958

Eitzen, David; Zimmermann, Alex

2012-01-14

201

Estimation of EMI Impact by Cellular Radio on Implantable Cardiac Pacemakers in Elevator Using EMF Distributions Inside Human Body  

NASA Astrophysics Data System (ADS)

The purpose of this study is to estimate the possible effect of cellular radio on implantable cardiac pacemakers in elevators. We previously investigated pacemaker EMI in elevator by examining the E-field distribution of horizontal plane at the height of expected for implanted pacemakers inside elevators. In this paper, we introduce our method for estimating EMI impact to implantable cardiac pacemakers using EMF distributions inside the region of the human body in which pacemakers are implanted. Simulations of a human phantom in an elevator are performed and histograms are derived from the resulting EMF distributions. The computed results of field strengths are compared with a certain reference level determined from experimentally obtained maximum interference distance of implantable cardiac pacemakers. This enables us to carry out a quantitative evaluation of the EMI impact to pacemakers by cellular radio transmission. This paper uses a numerical phantom model developed based on an European adult male. The simulations evaluate EMI on implantable cardiac pacemakers in three frequency bands. As a result, calculated E-field strengths are sufficiently low to cause the pacemaker to malfunction in the region examined.

Kitagawa, Atsushi; Hikage, Takashi; Nojima, Toshio; Simba, Ally Y.; Watanabe, Soichi

202

Simplified Vector Control with Adaptive Back-EMF Parameter Adjustment for Position Sensorless Permanent Magnet Synchronous Motors  

NASA Astrophysics Data System (ADS)

A previously reported vector control method for position sensorless permanent magnet synchronous motors involves the use of controllers with simple block configurations. However, the performance of this method can be affected by the erroneous setting of the motor parameters because a feedback compensator is not used. In this study, the effects of these errors on the steady-state performance of the drive control examined under various error conditions. It was found that the amplitude of the motor current increases when the parameter error is nonzero; the effect of the back-EMF parameter error was especially found to be large. On the basis of this observation, the use of a new compensator named back-EMF parameter adjustment is proposed. Simulation results and experimental results showed that the proposed method can compensate for the increase in the amplitude of the motor current resulting from the occurrence of motor parameter errors. A theoretical analysis showed that the performance of our vector control method, which involves the use of the new compensator, is affected only by errors in the d-axis inductance parameter Ld. Therefore, even if there are errors in the other motor parameters, the motor current for the constant load condition can be minimized by using the proposed method.

Sakamoto, Kiyoshi; Iwaji, Yoshitaka; Kaneko, Daigo; Takeuchi, Toshihiro; Endo, Tsunehiro; Kawamura, Atsuo

203

On Stationary Strategies for Absolutely Continuous Houses  

Microsoft Academic Search

Whether stationary families of strategies are uniformly adequate for a leavable, analytically measurable, nonnegative gambling problem whose optimal return function is everywhere finite is a question which remains open. It is, however, given an affirmative answer if, for example, the fortune space is Euclidean and all nontrivial, available gambles are absolutely continuous with respect to Lebesgue measure.

Lester E. Dubins; William D. Sudderth

1979-01-01

204

Precision absolute positional measurement of laser beams.  

PubMed

We describe an instrument which, coupled with a suitable coordinate measuring machine, facilitates the absolute measurement within the machine frame of the propagation direction of a millimeter-scale laser beam to an accuracy of around 4 ?m in position and 20 ?rad in angle. PMID:23669658

Fitzsimons, Ewan D; Bogenstahl, Johanna; Hough, James; Killow, Christian J; Perreur-Lloyd, Michael; Robertson, David I; Ward, Henry

2013-04-20

205

On the Measurement of Absolute Velocities  

Microsoft Academic Search

Inertial observers can not only measure their absolute velocities but that of light as well, thereby being able to shed insight into the principle of the constancy of light velocity. The light speeds cv, though considered to conflict with this principle, are shown herein to not be true physical entities. Keywords: special relativity theory, time, coordinate systems, relative velocity. Consider

A. C. V. Ceapa

206

Conditions for Equilibrium at Negative Absolute Temperatures  

Microsoft Academic Search

In the classical phenomenological thermodynamic theory of Gibbs, equilibrium is defined as the state of maximum entropy at constant energy, and a theorem is proved (the energy theorem) which asserts that the equilibrium state is the state of minimum energy at fixed entropy. This theorem is not true for systems at negative absolute temperatures. By examining a familiar statistical model

Bernard D. Coleman; Walter Noll

1959-01-01

207

Negative absolute temperatures and rotating temperatures  

Microsoft Academic Search

Although negative absolute temperatures, and rotating temperatures, only arise in certain special situations it is of interest to consider what, if any, changes have to be made in traditional thermodynamics in order to accommodate them. It is found that about the only change required is a slight modification of the Kelvin-Planck formulation of the second law. The terms, hotter, colder,

J. G. Powles

1963-01-01

208

On the absolute configuration of matricin.  

PubMed

The assignment of the absolute configuration of matricin rests on indirect evidence. On the basis of synthetic, NMR and CD studies with its decomposition product, chamazulene carboxylic acid, we were able to firmly establish the accepted 3S,3aR,4S,9R,9aS,9bS configuration of matricin. PMID:11345709

Goeters, S; Imming, P; Pawlitzki, G; Hempel, B

2001-04-01

209

It's Not All Relative: Relative Versus Absolute  

NSDL National Science Digital Library

Learning about the sizes of things and scale engages students in thinking about conceptual benchmarks for sizes. In this investigation, students learn to order objects on a relative scale, as well as to accurately label actual or absolute sizes. In additi

Taylor, Amy R.; Jones, M. G.; Falvo, Michael R.

2009-04-01

210

Absolute Measurement of exp 152 Eu.  

National Technical Information Service (NTIS)

A new method of the absolute measurement for exp 152 Eu was established based on the 4 pi beta - gamma spectroscopic anti-coincidence method. It is a coincidence counting method consisting of a 4 pi beta -counter and a Ge(Li) gamma -ray detector, in which...

H. Baba S. Baba S. Ichikawa T. Sekine I. Ishikawa

1981-01-01

211

Investigation of Absolute Light Output Measurement Techniques  

Microsoft Academic Search

The recently published works on new measurement techniques of the scintillators' absolute light yield triggered our response in the attempt to find out a way to resolve the disagreements between the old, established technique and the emerging, new one. Authors of the new approach argue that the conditions in which the photomultipliers photocathodes quantum efficiencies' characteristics are being determined differ

Marek Moszynski; Antoni Nassalski; Agnieszka Syntfeld-Kazuch; Tomasz Szczesniak; L. Swiderski

2007-01-01

212

Investigation of Absolute Light Output Measurement Techniques  

Microsoft Academic Search

The recently published works on new measurement techniques of the scintillators' absolute light yield triggered our response in the attempt to find out a way to resolve the disagreements between the old, established technique and the emerging, new one. Authors of the new approach argue that the conditions in which the photomultipliers photocathodes quantum efficiencies' characteristics are being determined differ

M. Gierlik; M. Moszynski; A. Nassalski; A. Syntfeld-Kazuch; T. Szczesniak; L. Swiderski

2006-01-01

213

Global absolute sea level: The Hawaiian network  

Microsoft Academic Search

NOAA has begun work on a pilot absolute sea level network in Hawaii. Tide gauge stations on the islands of Hawaii, Maui, Oahu, and Kauai have been upgraded by installing Next Generation Water Level Measurements Systems (NGWLMS). A regular program of monitoring the stability of each tide gauge in the International Earth Rotation Service (IERS) conventional terrestrial reference frame has

William E. Carter; Miranda Chin; J. Ross Mackay; George Peter; Wolfgang Scherer; John Diamante

1988-01-01

214

Direct Measurement of Absolute Thermoelectric Coefficients Through Electronic Fluctuations  

NASA Astrophysics Data System (ADS)

This manuscript focuses on the further development of a novel experimental technique that exploits the fundamental fluctuation spectrum of the electron ensemble in any electrically conductive material. The electronic fluctuation spectrum, when measured in the hydrodynamic regime, carries a great deal of transport property information. Subsequently, Green-Kubo transport theory, which is based upon the correlation function's temporal decay equivalence to transport coefficients, may be applied to the experimental data. The cross-correlation functions of electronic charge and thermal energy allow a direct measurement of the absolute thermoelectric (Seebeck and Peltier) coefficients. The experiment is run on materials in complete energetic equilibrium, i.e., where no thermal or electrical gradients are present. The experimental data result in direct measurements of the electrical resistivity, electronic thermal conductivity, Lorenz number, and Seebeck and Peltier coefficients. Having validated the results on several metals, this work reports further validation of the experimental technique on a baseline semiconductor: 99.999% pure bismuth telluride. The methodology incorporates a double validation technique through comparative measurements against traditional experimental results and accepted results from the literature. Excellent agreement is found, thus lending further validity and understanding to this emerging experimental technique.

Garrity, Patrick L.; Radosti, Whitney V.

2012-06-01

215

Direct observation of solidification microstructures around absolute stability  

SciTech Connect

This paper presents, for the first time, experimental evidence for absolute stability in a transparent alloy. The succinonitrile-argon system was used to investigate the morphological transition from a cellular to a planar solid-liquid interface at high solidification velocities. Directional solidification of the organic contained in thin capillary tubes was observed in situ with an optical microscope. At the maximum interface velocity of 1.5 mm/s, a reduction of the solute content of the alloy resulted in a morphological transition from a cellular to a planar growth front. This transition developed in three stages: (1) transition from deep cylindrical cells to mixed patterns of cylindrical and elongated cells; (ii) transition from cylindrical and elongated cells to low amplitude cells; (iii) transition from low amplitude cells to plane front. Within the limits of uncertainties with respect to the material properties and the thermal gradient, correspondence between the experimental results on plane front transition and linear stability theory exists. It is shown that the transitions observed are located in the region near the limit point of the neutral stability curve on the branch for absolute morphological stability.

Ludwig, A.; Kurz, W. [Swiss Federal Inst. of Tech., Lausanne (Switzerland). Dept. of Materials

1996-09-01

216

Negative absolute temperature for motional degrees of freedom.  

PubMed

Absolute temperature is usually bound to be positive. Under special conditions, however, negative temperatures-in which high-energy states are more occupied than low-energy states-are also possible. Such states have been demonstrated in localized systems with finite, discrete spectra. Here, we prepared a negative temperature state for motional degrees of freedom. By tailoring the Bose-Hubbard Hamiltonian, we created an attractively interacting ensemble of ultracold bosons at negative temperature that is stable against collapse for arbitrary atom numbers. The quasimomentum distribution develops sharp peaks at the upper band edge, revealing thermal equilibrium and bosonic coherence over several lattice sites. Negative temperatures imply negative pressures and open up new parameter regimes for cold atoms, enabling fundamentally new many-body states. PMID:23288533

Braun, S; Ronzheimer, J P; Schreiber, M; Hodgman, S S; Rom, T; Bloch, I; Schneider, U

2013-01-01

217

Absolute measurement of activity of ??Au foils using the 4??-? coincidence counting method and corrections by the Monte Carlo simulation.  

PubMed

The thermal neutron fluence rate is determined by the gold activation method. The absolute activity of the irradiated gold foil is measured by a 4??-? coincidence counter. Using this method, corrections for the detection of conversion electrons and gamma rays by a 4?? counter are very important to obtain accurate absolute activity. In this work, Monte Carlo simulations were performed to derive the correction factor K. The absolute measurement of (198)Au activity for 20-100 ?m thickness Au foils were performed to verify the calculating model of the 4??-? coincidence counting system. PMID:21406431

Nishiyama, Jun; Harano, Hideki; Matsumoto, Tetsuro; Sato, Yasushi; Uritani, Akira; Kudo, Katsuhisa

2011-03-15

218

Thermodynamic stabilities of SrCeO3 and Sr2CeO4 using the fluoride EMF technique  

NASA Astrophysics Data System (ADS)

The standard Gibbs energies of formation of SrCeO3 and Sr2CeO4 were measured by the EMF method using CaF2 as a solid electrolyte. Three fluoride galvanic cells (I III) were constructed in order to determine ?fG? of SrCeO3. The ?fG? of Sr2CeO4 was determined using galvanic cell (IV). The cells used were Pt,O2(g)(1bar),SrO(s),SrF2(s)|CaF2|SrF2(s),CeO2(s),SrCeO3(s),O2(g)(1bar),Pt Pt,O2(g)(1bar),SrO(s),SrF2(s)|SrF2|SrF2(s),CeO2(s),SrCeO3(s),O2(g)(1bar),Pt Pt,O2(g)(1bar),SrF2(s),CeO2(s),SrCeO3(s)|CaF2|CaF2(s),CaO(s),O2(1bar),Pt Pt,O2(g)(1bar),SrO(s),SrF2(s)|CaF2|SrF2(s),SrCeO3(s),Sr2CeO4(s),O2(1bar),Pt The standard Gibbs energy of formation of SrCeO3, derived from the mean of the EMFs of the above galvanic cells (I to III), is given by the following expression: ?fG(SrCeO3)17(kJmol)=-1703+0.327T(K)(788 1142K) By combining this expression with the EMF measured using Cell IV, the following expression was obtained for the temperature dependence of the standard Gibbs energy of formation of Sr2CeO4 ?fG(Sr2CeO4)21(kJmol)=-2307+0.4400T(K)(805 1066K)

Pankajavalli, R.; Ananthasivan, K.; Anthonysamy, S.; Vasudeva Rao, P. R.

2005-02-01

219

Quantum simulators at negative absolute temperatures  

NASA Astrophysics Data System (ADS)

We propose that negative absolute temperatures in ultracold atomic clouds in optical lattices can be used to simulate quantum systems in new regions of phase diagrams. First we discuss how the attractive SU(3) Hubbard model in three dimensions can be realized using repulsively interacting 173Yb atoms, then we consider how an antiferromagnetic S=1 spin chain could be simulated using spinor 87Rb or 23Na atoms. The general idea to achieve negative absolute temperatures is to reverse the sign of the external harmonic potential. Energy conservation in a deep optical lattice imposes a constraint on the dynamics of the cloud, which can relax toward a T<0 state. As the process is strongly nonadiabatic, we estimate the change of the entropy.

Rapp, kos

2012-04-01

220

Absolute calibration of TFTR helium proportional counters  

SciTech Connect

The TFTR helium proportional counters are located in the central five (5) channels of the TFTR multichannel neutron collimator. These detectors were absolutely calibrated using a 14 MeV neutron generator positioned at the horizontal midplane of the TFTR vacuum vessel. The neutron generator position was scanned in centimeter steps to determine the collimator aperture width to 14 MeV neutrons and the absolute sensitivity of each channel. Neutron profiles were measured for TFTR plasmas with time resolution between 5 and 50 ms depending upon count rates. The He detectors were used to measure the burnup of 1 MeV tritons in deuterium plasmas, the transport of tritium in trace tritium experiments, and the residual tritium levels in plasmas following 50:50 DT experiments.

Strachan, J.D.; Barnes, C.W.; Diesso, M.; Jassby, D.; Johnson, L.; Loughlin, M.; McCauley, S.; Munsat, T.; Roquemore, A.L. (Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States))

1995-02-01

221

Absolute calibration of TFTR helium proportional counters  

SciTech Connect

The TFTR helium proportional counters are located in the central five (5) channels of the TFTR multichannel neutron collimator. These detectors were absolutely calibrated using a 14 MeV neutron generator positioned at the horizontal midplane of the TFTR vacuum vessel. The neutron generator position was scanned in centimeter steps to determine the collimator aperture width to 14 MeV neutrons and the absolute sensitivity of each channel. Neutron profiles were measured for TFTR plasmas with time resolution between 5 msec and 50 msec depending upon count rates. The He detectors were used to measure the burnup of 1 MeV tritons in deuterium plasmas, the transport of tritium in trace tritium experiments, and the residual tritium levels in plasmas following 50:50 DT experiments.

Strachan, J.D.; Diesso, M.; Jassby, D.; Johnson, L.; McCauley, S.; Munsat, T.; Roquemore, A.L. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Barnes, C.W. [Princeton Univ., NJ (United States). Plasma Physics Lab.]|[Los Alamos National Lab., NM (United States); Loughlin, M. [Princeton Univ., NJ (United States). Plasma Physics Lab.]|[JET Joint Undertaking, Abingdon (United Kingdom)

1995-06-01

222

Quantifying absolute carbon isotope ratios by AMS  

NASA Astrophysics Data System (ADS)

Our AMS produced a ratio of instrument transmissions for 14C and 13C equal to 13/14 to 0.22 0.06% accuracy at a specific charge-changing energy of 235 keV and giving absolute isotope ratios with that mass correction. The ratio for 13C and 12C transmissions was 12/13 at 215 keV. A differential equation model of energetic ion and atom transport through the gas collision cell was constructed with functions representing experimental cross-sections for all collision effects. This model showed cation yield dependencies that were linear with energy for the monoenergetic isotopic ions at the energies that we measured, explaining the inverse mass dependence. The model predicted multiple lower energies that have this dependence and, more importantly, two low energies at which cation yields were equal for pairs of isotopes, presaging potential absolute isotope ratio measurements at low MS energies.

Vogel, John S.; Giacomo, Jason A.; Dueker, Stephen R.

2013-01-01

223

FOC Absolute Sensitivity (F/48 Relay)  

NASA Astrophysics Data System (ADS)

The absolute DQE for the f/48 camera has not yet been directly measured in orbit. This has been in part due to the absence of faint enough standards. This proposal will attempt to correct this deficiency by observations of UV standard stars with combinations of filters and small formats to achieve count rates that are not seriously nonlinear. Because of the use of small formats, interactive acquisitions will be required as well as special commanding for nonstandard formats. Internal LED exposures will also be necessary to geometrically calibrate the nonstandard format and to tie its absolute response to those of other formats (there is a significant format- dependent response variation for f/48).

Paresce, Francesco

1993-07-01

224

Absolute pitch in autism: A case study  

Microsoft Academic Search

We present the case study of QC, a low-functioning adolescent with autism, who possesses the special ability of absolute pitch. QC participated in an in-depth assessment of pitch perception and processing systems relevant for current cognitive models of autism. Her performance was compared to that of mental age-and chronological age-matched groups of persons with average intelligence, or to that of

L. Mottron; I. Peretz; S. Belleville; N. Rouleau

1999-01-01

225

Absolute Ultraviolet Stellar Irradiances from SORCE SOLSTICE  

Microsoft Academic Search

The SOLar-STellar Irradiance Comparison Experiment (SOLSTICE) on the SOlar Radiation and Climate Experiment (SORCE) spacecraft is a grating spectrometer that has been measuring both solar and stellar fluxes in the 115-300 nm range since 2003. Preflight instrument calibration using the SURF III synchrotron source yields an uncertainty in the absolute stellar irradiances of just a few percent.The SOLSTICE program stars

Martin Snow; W. E. McClintock; T. N. Woods; G. Rottman

2006-01-01

226

The absolute bioavailability of caffeine in man  

Microsoft Academic Search

The absolute bioavailability of orally administered caffeine was investigated in 10 healthy adult male volunteers, aged 18.8 to 30.0 years. The subjects were administered a 5 mg\\/kg dose of caffeine as either an aqueous oral solution or an intravenous infusion, on separate occasions about 1 week apart, in a randomized crossover fashion. Plasma samples were collected over the 24-h period

J. Blanchard; S. J. A. Sawers

1983-01-01

227

Clock retardation, absolute space, and special relativity  

Microsoft Academic Search

We consider a sequence of absolute-space kinematical theories which differ more or less from the special theory of relativity (STR) in the amount of clock retardation which they predict, but which agree with STR with respect to roundtrip light experiments, such as Michelson-Morley and Kennedy-Thorndike. This sequence of theories is imbedded in the synchrony-free formulation of STR developed by Winnie

Carlo Giannoni

1979-01-01

228

Training the absolute identification of pitch  

Microsoft Academic Search

Two methods for training the absolute judgment of pitch, reference training and series training, were studied. Reference training\\u000a concentrated during training on the identification of three reference tones in a set of nine pure tones, while series training\\u000a gave equal weight during training to the identification of all nine tones. Results of pre- and posttraining tests, scored\\u000a for the number

Lola L. Cuddy

1970-01-01

229

[Absolute configuration and enantiomeric purity of celiprolol].  

PubMed

The absolute configuration of (+)-celiprolol ([alpha]D = +6.3 degrees in CHCl3) was established by a 9-step synthesis via the (+) (R)-acetonide of (R)-glyceraldehyde. This result was confirmed by the Cupra-A CD-spectra of the isopropyl and hydroxy analogs. The enantiomeric purity was determined by NMR analysis of the diastereomeric amide esters obtained by reaction of celiprolol with 2 mol of alpha-methoxy-alpha-trifluoromethyl-phenylacetic acid chloride (Mosher's reagent). PMID:2946303

Hofer, O; Schlgl, K

1986-08-01

230

Absolute absorption of ozone in the midinfrared  

SciTech Connect

The absolute absorption of ozone in the midinfrared has been measured relative to 253.7-nm ultraviolet absorption to an accuracy of 1% using a Bruker Fourier transform spectrometer. These new results agree with previous measurements by diode laser measurements after the latter are corrected for more recent infrared calculations and ultraviolet cross sections. They also agree with a determination based on refractive index measurements in the infrared. 16 refs., 4 figs., 3 tabs.

Pickett, H.M.; Peterson, D.B.; Margolis, J.S. (California Inst. of Technology, Pasadena (United States))

1992-12-20

231

Impedance of a Spacecraft-Borne Antenna in the Magnetospheric Plasma and Quasi-Equilibrium Noise EMF in the Lower-Hybrid Frequency Band  

NASA Astrophysics Data System (ADS)

We present analytical and numerical estimations of the value and frequency dependence of the impedance and noise electromotive force (EMF) in the context of the conditions which correspond to the trajectories and parameters of the antennas borne by geophysical monitoring satellites. The estimations were obtained for two circular orbits at altitudes of 600 and 1200 km over the Earth's surface in the frequency range from 20 to 120 kHz, which corresponded to the area of the lower-hybrid resonance, where a higher level of noise emissions is observed at the altitudes under consideration. It is shown that near the lower-hybrid resonance frequency, the real part of the antenna impedance is determined by the resonant "monopole" loss by radiation of quasipotential waves. In the nonresonant frequency band (at the frequencies below the frequency of the lowerhybrid resonance), the antenna reactance is determined by the transit loss, which is, however, low as compared with the resonant loss. When the noise was calculated, the medium was assumed to be a two-temperature plasma. The spectral density of the power of the noise EMF lies in the range and is determined mainly by suprathermal electrons. In the nonresonant frequency band, the efficient temperature of noise radiation is equal to the temperature of the "cold" plasma component, and the antenna reactance is determined by the transit loss, i.e., the level of the noise EMF is low as compared with the EMF in the resonant frequency band.

Chugunov, Yu. V.; Grach, V. S.; Pasmanik, D. L.

2013-07-01

232

Nepal and the Americas: Can Electromagnetic Field (EMF) Signals Be Detected There That Yield Information About Culturally Dictated Spiritual Values, and Can Computers Interface Their Assessment?  

NASA Astrophysics Data System (ADS)

Nepal has a particularly rich tradition of culturally developed views on the material and spiritual worlds, and also has a powerful natural environment that may generate EMFs in conjunction with natural phenomena. We have an interest in determining whether these can be detected by portable technological means, and recording such data on notebook-type computers for analysis and evaluation. One goal is to assess whether historic Native Americans, such as Maine's and New Hampshire's Molly Ockett, may have been motivated in their selection of special, and perhaps, to them, "sacred" sites for their attention and as possible burial sites. Some of these may have been chosen on the basis of the EMFs that seem to emanate from them, and their assessment of what they meant to their worldviews. Do some Amerindians consider the EMF and reincarnation as requiring their rejection of material aspects of existence? Could other traditional cultures, or even suicidal terrorists, be sensitive to "information" they may receive from the EMF?

Aryal, Sanjita; Mc Leod, Roger D.; Mc Leod, David M.

2002-10-01

233

Molten Carbonate Fuel Cell Program. Progress Report for Period January 1-March 31, 1979: EMF And Temperature Relaxation in LiKCO sub 3 Tiles; Transference Cell Measurements.  

National Technical Information Service (NTIS)

Progress has been made in resolving the thermoelectric contributions to the relaxing EMF of electrolyzed LiKCO sub 3 -LiAlO sub 2 tiles in a study of mass transport in molten carbonate fuel cell electrolytes. The thermoelectric effect is a measurable cont...

J. Braunstein H. R. Bronstein A. R. Manner J. Nwalor D. H. Smith

1979-01-01

234

A Cryogenic Radiometer for Absolute Radiometric Measurements  

NASA Astrophysics Data System (ADS)

The adoption in 1979 of a new definition of the candela, which permitted a detector-based approach to the realization of the unit, has emphasized the importance of high-accuracy absolute radiation detectors. This paper describes a new electrical-substitution absolute radiometer operating at 5 K, based on a standard commercial helium cryostat, which has been developed at NPL for optical radiant-power measurements. The principal advantages of operating the radiometer at liquid helium temperatures are that the detector can be a large, highly absorbing cavity (absorptivity 99.998%) and that exact equivalence of electrical and radiant heating can be clearly demonstrated. It will be the primary absolute detector for a new realization of the candela at NPL and will provide the basis for the development of a wider range of radiometric and spectroradiometric standards. The use of the radiometer to measure the radiant power of an intensity-stabilized laser source at the milliwatt level with an uncertainty of 4 parts in 105 is also described, together with its application in the determination of the responsivity of transfer-standard detectors, such as silicon photodiodes.

Martin, J. E.; Fox, N. P.; Key, P. J.

1985-01-01

235

Chemical composition of French mimosa absolute oil.  

PubMed

Since decades mimosa (Acacia dealbata) absolute oil has been used in the flavor and perfume industry. Today, it finds an application in over 80 perfumes, and its worldwide industrial production is estimated five tons per year. Here we report on the chemical composition of French mimosa absolute oil. Straight-chain analogues from C6 to C26 with different functional groups (hydrocarbons, esters, aldehydes, diethyl acetals, alcohols, and ketones) were identified in the volatile fraction. Most of them are long-chain molecules: (Z)-heptadec-8-ene, heptadecane, nonadecane, and palmitic acid are the most abundant, and constituents such as 2-phenethyl alcohol, methyl anisate, and ethyl palmitate are present in smaller amounts. The heavier constituents were mainly triterpenoids such as lupenone and lupeol, which were identified as two of the main components. (Z)-Heptadec-8-ene, lupenone, and lupeol were quantified by GC-MS in SIM mode using external standards and represents 6%, 20%, and 7.8% (w/w) of the absolute oil. Moreover, odorant compounds were extracted by SPME and analyzed by GC-sniffing leading to the perception of 57 odorant zones, of which 37 compounds were identified by their odorant description, mass spectrum, retention index, and injection of the reference compound. PMID:20070087

Perriot, Rodolphe; Breme, Katharina; Meierhenrich, Uwe J; Carenini, Elise; Ferrando, Georges; Baldovini, Nicolas

2010-02-10

236

Absolute Calibration of AXAF Effective Area  

NASA Astrophysics Data System (ADS)

In order to measure the absolute x-ray flux from objects observed by AXAF, the absolute effective area of the telescope must be known. Because there are no standard candles in the x-ray sky, a prelaunch calibration must be done. The overall effective area of the combined optic and focal plane detectors requires a knowledge of the absolute flux in the incident x-ray beam that illuminates them in the X-ray Calibration Facility at Marshall Space Flight Center. In order to calibrate the beam, a standard detector is needed. We report on the approach being developed to calibrate standard detectors to 1% in effective area. Basic data on physical properties of materials, such as the Henke tables, are not adequate. This is true both because of imprecision in the data, and difficulties with designing detectors whose overall efficiency can be synthesized from a knowledge of constituent properties. Therefore, we resort to calibrating the detector against a standard source, the PTB beam lines at the BESSY synchrotron. The PTB white beam line is calibrated to 0.3%, and the monochromatic line to 1% over the lower portion of the AXAF energy range, and to a few percent over the higher energy range. Special precautions are taken to assure that the detectors are stable following calibration at BESSY. These include dealing with condensation of frozen water vapor on a germanium detector, and providing a built-in radioactive source to check stability. The AXAF effective area is sensitive to small changes in particulate and molecular contamination on its x-ray optics. Therefore, the absolute standard established on the ground must be transferred to orbit. To accomplish this, AXAF employs radioactive sources mounted forward of the optic. X-rays from these sources reflected from the optic are detected by a flight focal plane detector. The counting rates from before and after launch can be used to measure any change in the effective area, establishing the on-orbit absolute effective area.

Kellogg, E.; Tsiang, E.; Schwartz, D.; Hughes, J.; Gaetz, T.; Wargelin, B.; Kolodziejczak, J.; Scholze, F.; Ulm, G.; O'dell, S.; Elsner, R.

1995-12-01

237

Dynamic control of adsorption sensitivity for photo-EMF-based ammonia gas sensors using a wireless network.  

PubMed

This paper proposes an adsorption sensitivity control method that uses a wireless network and illumination light intensity in a photo-electromagnetic field (EMF)-based gas sensor for measurements in real time of a wide range of ammonia concentrations. The minimum measurement error for a range of ammonia concentration from 3 to 800 ppm occurs when the gas concentration magnitude corresponds with the optimal intensity of the illumination light. A simulation with LabView-engineered modules for automatic control of a new intelligent computer system was conducted to improve measurement precision over a wide range of gas concentrations. This gas sensor computer system with wireless network technology could be useful in the chemical industry for automatic detection and measurement of hazardous ammonia gas levels in real time. PMID:22346680

Vashpanov, Yuriy; Choo, Hyunseung; Kim, Dongsoo Stephen

2011-11-22

238

Floridas Miami Tequesta Indian Site, Its Calusa Indian Locations, the Matacumbe Keys, and Orlandos Wikiwa Springs Generate Environmentally Significant EMFs.  

NASA Astrophysics Data System (ADS)

Florida purchased the Tequesta ([Langue] doc Christ Spirit-signal) Indian site along the Miami River site that vigorously pulsates with even minor rainstorms entering or leaving the area. Although there is a laughable chimera of a fountain of youth associated with Ponce de Leons discovery of the Florida peninsula in about AD 1513, the Calusa (Royal Christ Jesus Spirit-signal) Indian Nation has an associated significance with EMF signals they possibly monitored throughout their area of activity. Our efforts have also led to the investigation of cultural and other influences implied by the Matacumbe Keys that indicate a shared commonality of awareness with Native Americans of the northeast such as Metacomet, or regions like Maines Grand Lake Matagamon and its associated electromagnetic Spirit Signal. Wikiwa Springs near Orlando shares much with Massachusetts (adherent of serpent Jesus Christ Spirit-signal) Natick, and New Hampshires Naticook Island. These are the locales of environmentally sensitive instrumentation.

Mac Dougall, Jean S.; Mc Leod, Roger D.; Mc Leod, David M.

2003-10-01

239

Dynamic Control of Adsorption Sensitivity for Photo-EMF-Based Ammonia Gas Sensors Using a Wireless Network  

PubMed Central

This paper proposes an adsorption sensitivity control method that uses a wireless network and illumination light intensity in a photo-electromagnetic field (EMF)-based gas sensor for measurements in real time of a wide range of ammonia concentrations. The minimum measurement error for a range of ammonia concentration from 3 to 800 ppm occurs when the gas concentration magnitude corresponds with the optimal intensity of the illumination light. A simulation with LabView-engineered modules for automatic control of a new intelligent computer system was conducted to improve measurement precision over a wide range of gas concentrations. This gas sensor computer system with wireless network technology could be useful in the chemical industry for automatic detection and measurement of hazardous ammonia gas levels in real time.

Vashpanov, Yuriy; Choo, Hyunseung; Kim, Dongsoo Stephen

2011-01-01

240

In-Flight Absolute Radiometric Calibration of the Thematic Mapper.  

National Technical Information Service (NTIS)

The TM multispectral scanner system was calibrated in an absolute manner before launch. To determine the temporal changes of the absolute radiometric calibration of the entire system, spectroradiometric measurements of the ground and the atmosphere were m...

K. R. Castle R. G. Holm C. J. Kastner J. M. Palmer P. N. Slater

1983-01-01

241

A new absolute magnitude calibration for red clump stars  

NASA Astrophysics Data System (ADS)

We present a new MV absolute magnitude calibration for the red clump stars.We used the red clump stars in open and globular clusters.Precise absolute magnitudes can be estimated from the calibration formula.

Bilir, S.; Ak, T.; Ak, S.; Yontan, T.; Bostanc?, Z. F.

2013-10-01

242

Cosmological Frames for Theories with Absolute Parallelism  

NASA Astrophysics Data System (ADS)

The vierbein (tetrad) fields for closed and open Friedmann-Robertson-Walker cosmologies are hard to work out in most of the theories featuring absolute parallelism. The difficulty is traced in the fact that these theories are not invariant under local Lorentz transformations of the vierbein. We illustrate this issue in the framework of f(T) theories and Born-Infeld determinantal gravity. In particular, we show that the early Universe as described by the Born-Infeld scheme is singularity free and naturally inflationary as a consequence of the very nature of Born-Infeld gravitational action.

Fiorini, Franco; Ferraro, Rafael

2011-05-01

243

Absolute calibration of the Auger fluorescence detectors  

SciTech Connect

Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a light source at the telescope aperture. The technique accounts for the combined effects of all detector components in a single measurement. The calibrated 2.5 m diameter light source fills the aperture, providing uniform illumination to each pixel. The known flux from the light source and the response of the acquisition system give the required calibration for each pixel. In the lab, light source uniformity is studied using CCD images and the intensity is measured relative to NIST-calibrated photodiodes. Overall uncertainties are presently 12%, and are dominated by systematics.

Bauleo, P.; Brack, J.; Garrard, L.; Harton, J.; Knapik, R.; Meyhandan, R.; Rovero, A.C.; /Buenos Aires, IAFE; Tamashiro, A.; Warner, D.

2005-07-01

244

Telescope alignment with the absolute distance interferometer  

NASA Astrophysics Data System (ADS)

Achieving optimal performance from a multiple element telescope is critically dependent on an element position sensing and control system. We first discuss the design of a novel absolute distance measuring interferometer with performance suitable for such a sensing system, and secondly describe how it can be simply integrated into the telescope. Features of the interferometer include an extended ambiguity range, high temporal bandwidth, and very high accuracy. The concept for the overall optical alignment system is expected to compensate in part for local atmospheric distortions as well as mechanical vibrations while not interfering with the optical performance of the telescope.

Massie, N. A.; Dunn, M. R.

1982-10-01

245

Continuum limit of electrostatic gyrokinetic absolute equilibrium  

SciTech Connect

Electrostatic gyrokinetic absolute equilibria with continuum velocity field are obtained through the partition function and through the Green function of the functional integral. The new results justify and explain the prescription for quantization/discretization or taking the continuum limit of velocity. The mistakes in the Appendix D of our earlier work [J.-Z. Zhu and G. W. Hammett, Phys. Plasmas 17, 122307 (2010)] are explained and corrected. If the lattice spacing for discretizing velocity is big enough, all the invariants could concentrate at the lowest Fourier modes in a negative-temperature state, which might indicate a possible variation of the dual cascade picture in 2D plasma turbulence.

Zhu Jianzhou [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

2012-06-15

246

Absolute entropies from molecular dynamics simulation trajectories  

NASA Astrophysics Data System (ADS)

A heuristic formula for calculating absolute entropies from the covariance matrix of atom-positional fluctuations was extensively tested. Because of its heuristic nature, the results obtained are compared to analytical expressions for an ensemble of harmonic oscillators, for the ideal gas, and to numerical results obtained from the equation of state for the Lennard-Jones fluid as a means of validation of the approximate formula for the entropy. The formula yields rather accurate results. The removal of translational and rotational rigid body motion and the effect of the various fitting procedures involved are discussed for the more realistic system of a ?-heptapeptide in solution.

Schfer, Heiko; Mark, Alan E.; van Gunsteren, Wilfred F.

2000-11-01

247

Inviscid axisymmetric absolute instability of swirling jets  

NASA Astrophysics Data System (ADS)

The propagation characteristics of inviscid axisymmetric linearized disturbances to swirling jets are investigated for two families of model velocity profiles. Briggs' method is applied to dispersion relations to determine when the basic swirling jets are absolutely or convectively unstable. The method is also applied to the neutral inertial waves used by Benjamin to characterize the subcritical or supercritical nature of the flow. Although these waves are neutral, Briggs' method nonetheless indicates a qualitative change in behaviour at Benjamin's criticality condition. The first model jet has uniform axial velocity, rigid-body rotation and issues into still fluid. A known difficulty in the application of Briggs' method to the analytical dispersion relation for inviscid waves in this flow is resolved. The difficulty is that the pinch point can cross into the left half of the complex-wavenumber plane, where waves grow exponentially with radius and fail to satisfy homogeneous boundary conditions. In this paper the physical consequences of this behaviour are explained. It is shown that if the still fluid is of infinite extent in the radial direction, then the jet is convectively unstable to axisymmetric waves, but if the jet is confined by an outer cylinder concentric with the jet axis, then it becomes absolutely unstable to axisymmetric waves provided that the swirl (ratio of azimuthal to axial velocity) is large enough. This destabilizing effect of confinement occurs however large the radius of the outer cylinder. A second family of model swirling jets with smooth profiles and a finite thickness shear layer at the jet edge is also studied. The inviscid stability equations are solved numerically in this case. The results from the analytical dispersion relations are reproduced as the shear layer thickness tends to zero. However, increasing this thickness acts to destabilize the absolute instability of axisymmetric waves, apparently due to the centrifugal instability present in the shear layer. It is suggested that the transition from convective to absolute instability could be associated with the onset of an unsteady vortex breakdown. The swirl required to produce this transition can be either greater, or less, than the swirl required to produce the transition from supercritical to subcritical flow, depending on the details of the basic velocity profiles. A codimension-two point in parameter space can exist where the unsteady bifurcation associated with the convectivesubcritical transition. Such codimension-two points can control a rich variety of nonlinear dynamical behaviour.

Healey, J. J.

248

Computing absolute and essential spectra using continuation  

NASA Astrophysics Data System (ADS)

A continuation approach to the computation of essential and absolute spectra of differential operators on the real line is presented. The advantages of this approach, compared with direct eigenvalue computations for the discretized operator, are the efficient and accurate computation of selected parts of the spectrum (typically those near the imaginary axis) and the option to compute nonlinear travelling waves and selected eigenvalues or other stability indicators simultaneously in order to locate accurately the onset to instability. We also discuss the implementation and usage of this approach with the software package AUTO and provide example computations for the FitzHugh Nagumo and the complex Ginzburg Landau equation.

Rademacher, Jens D. M.; Sandstede, Bjrn; Scheel, Arnd

2007-05-01

249

Absolute metastable atom-atom collision cross section measurements using a magneto-optical trap.  

PubMed

We present a new technique to measure absolute total collision cross sections from metastable neon atoms. The technique is based on the observation of the decay rate of trapped atoms as they collide with room temperature atoms. We present the first measurement of this kind using trapped neon atoms in the (3)P(2) metastable state colliding with thermal ground state argon. The measured cross section has a value of 556+/-26 A(2). PMID:17672750

Matherson, K J; Glover, R D; Laban, D E; Sang, R T

2007-07-01

250

Absolute metastable atom-atom collision cross section measurements using a magneto-optical trap  

SciTech Connect

We present a new technique to measure absolute total collision cross sections from metastable neon atoms. The technique is based on the observation of the decay rate of trapped atoms as they collide with room temperature atoms. We present the first measurement of this kind using trapped neon atoms in the {sup 3}P{sub 2} metastable state colliding with thermal ground state argon. The measured cross section has a value of 556{+-}26 A ring {sup 2}.

Matherson, K. J.; Glover, R. D.; Laban, D. E.; Sang, R. T. [Centre for Quantum Dynamics, Griffith University, Nathan QLD 4111 (Australia)

2007-07-15

251

Absolute Proper Motions of Southern Globular Clusters  

NASA Astrophysics Data System (ADS)

Our program involves the determination of absolute proper motions with respect to galaxies for a sample of globular clusters situated in the southern sky. The plates cover a 6(deg) x 6(deg) area and are taken with the 51-cm double astrograph at Cesco Observatory in El Leoncito, Argentina. We have developed special methods to deal with the modelling error of the plate transformation and we correct for magnitude equation using the cluster stars. This careful astrometric treatment leads to accuracies of from 0.5 to 1.0 mas/yr for the absolute proper motion of each cluster, depending primarily on the number of measurable cluster stars which in turn is related to the cluster's distance. Space velocities are then derived which, in association with metallicities, provide key information for the formation scenario of the Galaxy, i.e. accretion and/or dissipational collapse. Here we present results for NGC 1851, NGC 6752, NGC 6584, NGC 6362 and NGC 288.

Dinescu, D. I.; Girard, T. M.; van Altena, W. F.

1996-05-01

252

Absolute Cavity Pyrgeometer to Measure the Absolute Outdoor Longwave Irradiance with Traceability to International System of Units, SI  

SciTech Connect

This article describes a method of measuring the absolute outdoor longwave irradiance using an absolute cavity pyrgeometer (ACP), U.S. Patent application no. 13/049, 275. The ACP consists of domeless thermopile pyrgeometer, gold-plated concentrator, temperature controller, and data acquisition. The dome was removed from the pyrgeometer to remove errors associated with dome transmittance and the dome correction factor. To avoid thermal convection and wind effect errors resulting from using a domeless thermopile, the gold-plated concentrator was placed above the thermopile. The concentrator is a dual compound parabolic concentrator (CPC) with 180{sup o} view angle to measure the outdoor incoming longwave irradiance from the atmosphere. The incoming irradiance is reflected from the specular gold surface of the CPC and concentrated on the 11 mm diameter of the pyrgeometer's blackened thermopile. The CPC's interior surface design and the resulting cavitation result in a throughput value that was characterized by the National Institute of Standards and Technology. The ACP was installed horizontally outdoor on an aluminum plate connected to the temperature controller to control the pyrgeometer's case temperature. The responsivity of the pyrgeometer's thermopile detector was determined by lowering the case temperature and calculating the rate of change of the thermopile output voltage versus the changing net irradiance. The responsivity is then used to calculate the absolute atmospheric longwave irradiance with an uncertainty estimate (U{sub 95}) of {+-}3.96 W m{sup 02} with traceability to the International System of Units, SI. The measured irradiance was compared with the irradiance measured by two pyrgeometers calibrated by the World Radiation Center with traceability to the Interim World Infrared Standard Group, WISG. A total of 408 readings were collected over three different nights. The calculated irradiance measured by the ACP was 1.5 W/m{sup 2} lower than that measured by the two pyrgeometers that are traceable to WISG, with a standard deviation of {+-}0.7 W m{sup -2}. These results suggest that the ACP design might be used for addressing the need to improve the international reference for broadband outdoor longwave irradiance measurements.

Reda, I.; Zeng, J.; Scheuch, J.; Hanssen, L.; Wilthan, B.; Myers, D.; Stoffel, T.

2012-03-01

253

Absolute instability of a viscous hollow jet.  

PubMed

An investigation of the spatiotemporal stability of hollow jets in unbounded coflowing liquids, using a general dispersion relation previously derived, shows them to be absolutely unstable for all physical values of the Reynolds and Weber numbers. The roots of the symmetry breakdown with respect to the liquid jet case, and the validity of asymptotic models are here studied in detail. Asymptotic analyses for low and high Reynolds numbers are provided, showing that old and well-established limiting dispersion relations [J. W. S. Rayleigh, The Theory of Sound (Dover, New York, 1945); S. Chandrasekhar, Hydrodynamic and Hydromagnetic Stability (Dover, New York, 1961)] should be used with caution. In the creeping flow limit, the analysis shows that, if the hollow jet is filled with any finite density and viscosity fluid, a steady jet could be made arbitrarily small (compatible with the continuum hypothesis) if the coflowing liquid moves faster than a critical velocity. PMID:17358457

Gan-Calvo, Alfonso M

2007-02-06

254

Absolute Elastic Electron Scattering from Benzene  

NASA Astrophysics Data System (ADS)

Absolute differential cross-sections for vibrationally elastic electron scattering from benzene (C_6H_6) have been measured, for the first time, in the energy range from 4 to 20 eV and for scattering angles between 15^o and 130^o, using a crossed-beam apparatus. The cross-sections are characterised by strong forward-angle scattering due to the large dipole polarizability of the molecule and large-angle oscillations due to the effect of shape resonances. Favourable comparisons are made with a recent theoretical calculation^1 which uses a parameter-free, exact-static-exchange-correlation-polarization (SECP) potential to treat the electron-molecule interaction in all scattering symmetries. To our knowledge, this is the only contemporary calculation of differential elastic electron-C_6H6 scattering. ^1F.A. Gianturco and R.R. Lucchese, J. Chem. Phys. 108 6144, (1998)

Gulley, Robert; Buckman, Stephen

1999-10-01

255

In vivo absorption spectroscopy for absolute measurement  

PubMed Central

In in vivo spectroscopy, there are differences between individual subjects in parameters such as tissue scattering and sample concentration. We propose a method that can provide the absolute value of a particular substance concentration, independent of these individual differences. Thus, it is not necessary to use the typical statistical calibration curve, which assumes an average level of scattering and an averaged concentration over individual subjects. This method is expected to greatly reduce the difficulties encountered during in vivo measurements. As an example, for in vivo absorption spectroscopy, the method was applied to the reflectance measurement in retinal vessels to monitor their oxygen saturation levels. This method was then validated by applying it to the tissue phantom under a variety of absorbance values and scattering efficiencies.

Furukawa, Hiromitsu; Fukuda, Takashi

2012-01-01

256

Effect of a single 30?min UMTS mobile phone-like exposure on the thermal pain threshold of young healthy volunteers.  

PubMed

One of the most frequently investigated effects of radiofrequency electromagnetic fields (RF EMFs) on the behavior of complex biological systems is pain sensitivity. Despite the growing body of evidence of EMF-induced changes in pain sensation, there is no currently accepted experimental protocol for such provocation studies for the healthy human population. In the present study, therefore, we tested the effects of third generation Universal Mobile Telecommunications System (UMTS) RF EMF exposure on the thermal pain threshold (TPT) measured on the surface of the fingers of 20 young adult volunteers. The protocol was initially validated with a topical capsaicin treatment. The exposure time was 30?min and the genuine (or sham) signal was applied to the head through a patch antenna, where RF EMF specific absorption rate (SAR) values were controlled and kept constant at a level of 1.75?W/kg. Data were obtained using randomized, placebo-controlled trials in a double-blind manner. Subjective pain ratings were tested blockwise on a visual analogue rating scale (VAS). Compared to the control and sham conditions, the results provide evidence for intact TPT but a reduced desensitization effect between repeated stimulations within the individual blocks of trials, observable only on the contralateral side for the genuine UMTS exposure. Subjective pain perception (VAS) data indicated marginally decreased overall pain ratings in the genuine exposure condition only. The present results provide pioneering information about human pain sensation in relation to RF EMF exposure and thus may contribute to cover the existing gap between safety research and applied biomedical science targeting the potential biological effects of environmental RF EMFs. Bioelectromagnetics. 34:530-541. 2013 Wiley Periodicals, Inc. PMID:23787775

Vecsei, Zsuzsanna; Csath, Arpd; Thurczy, Gyrgy; Herndi, Istvn

2013-06-20

257

Thermodynamic and nonstoichiometric behavior of promising Hi-Tc cuprate systems via EMF measurements : a short review.  

SciTech Connect

Electromotive force (EMF) measurements of oxygen fugacities as a function of stoichiometry have been made on the YBa{sub 2}Cu{sub 3}O{sub x}, GdBa{sub 2}Cu{sub 3}O{sub x}, NdBa{sub 2}Cu{sub 3}O{sub x} and bismuth cuprate systems in the temperature range {approximately}400-750 C by means of an oxygen titration technique with an yttria-stabilized zirconia electrolyte. The shapes of the 400 C isotherms as a function of oxygen stoichiometry for the Gd and Nd cuprate systems suggest the presence of miscibility gaps at values of x that are higher than those in the YBa{sub 2}Cu{sub 3}O{sub x} system. For a given oxygen stoichiometry, oxygen partial pressures above GdBa{sub 2}Cu{sub 3}O{sub x} and NdBa{sub 2}Cu{sub 3}O{sub x} are higher (above x=6.5) than that for the promising YBa{sub 2}Cu{sub 3}O{sub x} system. A thermodynamic assessment and intercomparison of our partial pressure measurements with the results of related measurements will be presented.

Tetenbaum, M.

1999-02-24

258

Directly Relating Gas-Phase Cluster Measurements to Solution-Phase Hydrolysis, the Absolute Standard Hydrogen Electrode Potential, and the Absolute Proton Solvation Energy  

PubMed Central

Solution-phase, half-cell potentials are measured relative to other half-cell potentials, resulting in a thermochemical ladder that is anchored to the standard hydrogen electrode (SHE), which is assigned an arbitrary value of 0 V. A new method for measuring the absolute SHE potential is demonstrated in which gaseous nanodrops containing divalent alkaline-earth or transition-metal ions are reduced by thermally generated electrons. Energies for the reactions 1) M-(H2O)242+(g)+e?(g)?M(H2O)24+(g) and 2) M(H2O)242+(g)+e?(g)?MOH(H2O)23+(g)+H(g) and the hydrogen atom affinities of MOH(H2O)23+(g) are obtained from the number of water molecules lost through each pathway. From these measurements on clusters containing nine different metal ions and known thermochemical values that include solution hydrolysis energies, an average absolute SHE potential of +4.29 V vs. e?(g) (standard deviation of 0.02 V) and a real proton solvation free energy of ?265 kcal mol?1 are obtained. With this method, the absolute SHE potential can be obtained from a one-electron reduction of nanodrops containing divalent ions that are not observed to undergo one-electron reduction in aqueous solution.

Donald, William A.; Leib, Ryan D.; O'Brien, Jeremy T.; Williams, Evan R.

2009-01-01

259

On-orbit absolute temperature calibration using multiple phase change materials: overview of recent technology advancements  

NASA Astrophysics Data System (ADS)

NASA's anticipated plan for a mission dedicated to Climate (CLARREO) will hinge upon the ability to fly SI traceable standards that provide irrefutable absolute measurement accuracy. As an example, instrumentation designed to measure spectrally resolved infrared radiances will require high-emissivity calibration blackbodies that have absolute temperature uncertainties of better than 0.045K (3 sigma). A novel scheme to provide absolute calibration of temperature sensors onorbit, that uses the transient melt signatures from multiple phase change materials, has been demonstrated in the laboratory at the University of Wisconsin and is now undergoing technology advancement under NASA Instrument Incubator Program funding. Using small quantities of phase change material (less than half of a percent of the mass of the cavity), melt temperature accuracies of better than 10 mK have been demonstrated for mercury, water, and gallium (providing calibration from 233K to 303K). Refinements currently underway focus on ensuring that the melt materials in their sealed confinement housings perform as expected in the thermal and microgravity environment of a multi-year spaceflight mission. Thermal soak and cycling tests are underway to demonstrate that there is no dissolution from the housings into the melt materials that could alter melt temperature, and that there is no liquid metal embrittlement of the housings from the metal melt materials. In addition, NASA funding has been recently secured to conduct a demonstration of this scheme in the microgravity environment of the International Space Station.

Best, Fred A.; Adler, Douglas P.; Pettersen, Claire; Revercomb, Henry E.; Perepezko, John H.

2010-10-01

260

Three-position absolute measurement simulation and error analysis  

NASA Astrophysics Data System (ADS)

To meeting the testing requirements of high-precision optical surfaces, the absolute testing technology was used for the optical testing process. Three-Position absolute measurements with the advantage of few requested testing and testing conditions are often easily satisfaction were used to high-precision spherical surface shape testing. However in the error process of three-position absolute measurements, cat's position error has an important impact on finally measurement results, so three-position absolute measurement simulation and error analysis is necessary. In this paper, optical design software ZEMAX were used to built the model of three-position absolute measurement and three-position absolute sphere testing algorithm was used to get actual surface. Finally, some experiments about how to determine the location of standard cat's eye position were carried on and the experiment's result shows that defocus is the most important factor in cat's eye position measurement.

Yang, Peng; Wu, Fan; Hou, Xi

2011-06-01

261

Absolute luminosity measurements with the LHCb detector at the LHC  

Microsoft Academic Search

Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of

R. Aaij; B. Adeva; M. Adinolfi; C. Adrover; A. Affolder; Z. Ajaltouni; J. Albrecht; F. Alessio; M. Alexander; G. Alkhazov; P. Alvarez Cartelle; A. A. Alves Jr; S. Amato; Y. Amhis; J. Anderson; R. B. Appleby; O. Aquines Gutierrez; F. Archilli; L. Arrabito; A. Artamonov; M. Artuso; E. Aslanides; G. Auriemma; S. Bachmann; J. J. Back; D. S. Bailey; V. Balagura; W. Baldini; R. J. Barlow; C. Barschel; S. Barsuk; W. Barter; A. Bates; C. Bauer; Th. Bauer; A. Bay; I. Bediaga; K. Belous; I. Belyaev; E. Ben-Haim; M. Benayoun; G. Bencivenni; S. Benson; J. Benton; R. Bernet; M van Beuzekom; A. Bien; S. Bifani; A. Bizzeti; P. M. Bjrnstad; T. Blake; F. Blanc; C. Blanks; J. Blouw; S. Blusk; A. Bobrov; V. Bocci; A. Bondar; N. Bondar; W. Bonivento; S. Borghi; A. Borgia; T. J. V. Bowcock; C. Bozzi; T. Brambach; J. van den Brand; J. Bressieux; D. Brett; S. Brisbane; M. Britsch; T. Britton; N. H. Brook; H. Brown; A. Bchler-Germann; I. Burducea; A. Bursche; J. Buytaert; S. Cadeddu; J. M. Caicedo Carvajal; O. Callot; M. Calvi; M. Calvo Gomez; A. Camboni; P. Campana; A. Carbone; G. Carboni; R. Cardinale; A. Cardini; L. Carson; K. Carvalho Akiba; G. Casse; M. Cattaneo; M. Charles; Ph. Charpentier; N. Chiapolini; K. Ciba; X. Cid Vidal; G. Ciezarek; P. E. L. Clarke; M. Clemencic; H. V. Cliff; J. Closier; C. Coca; V. Coco; J. Cogan; P. Collins; F. Constantin; G. Conti; A. Contu; A. Cook; M. Coombes; G A Cowan; R. Currie; B. D'Almagne; C. D'Ambrosio; P. David; I. De Bonis; S. De Capua; M. De Cian; F. De Lorenzi; J. M. De Miranda; L. De Paula; P. De Simone; D. Decamp; M. Deckenhoff; H. Degaudenzi; M. Deissenroth; L. Del Buono; C. Deplano; O. Deschamps; F. Dettori; J. Dickens; H. Dijkstra; P. Diniz Batista; S. Donleavy; F. Dordei; A. Dosil Surez; D. Dossett; A. Dovbnya; F. Dupertuis; R. Dzhelyadin; C. Eames; S. Easo; U. Egede; V. Egorychev; S. Eidelman; D. van Eijk; F. Eisele; S. Eisenhardt; R. Ekelhof; L. Eklund; Ch. Elsasser; D. G. d'Enterria; D. Esperante Pereira; L. Estve; A. Falabella; E. Fanchini; C. Frber; G. Fardell; C. Farinelli; S. Farry; V. Fave; V. Fernandez Albor; M. Ferro-Luzzi; S. Filippov; C. Fitzpatrick; M. Fontana; F. Fontanelli; R. Forty; M. Frank; C. Frei; M. Frosini; S. Furcas; A. Gallas Torreira; D. Galli; M. Gandelman; P. Gandini; Y. Gao; J. C. Garnier; J. Garofoli; J. Garra Tico; L. Garrido; C. Gaspar; N. Gauvin; M. Gersabeck; T. Gershon; Ph. Ghez; V V Gligorov; C. Gbel; D. Golubkov; A. Golutvin; A. Gomes; H. Gordon; M. Grabalosa Gndara; R. Graciani Diaz; L. A. Granado Cardoso; E. Graugs; G. Graziani; A. Grecu; S. Gregson; B. Gui; E. Gushchin; Yu. Guz; T. Gys; G. Haefeli; C. Haen; S. C. Haines; T. Hampson; S. Hansmann-Menzemer; R. Harji; N. Harnew; J. Harrison; P. F. Harrison; J. He; V. Heijne; K. Hennessy; P. Henrard; J. A. Hernando Morata; E. van Herwijnen; E. Hicks; W. Hofmann; K. Holubyev; P. Hopchev; W. Hulsbergen; P. Hunt; T. Huse; R. S. Huston; D. Hutchcroft; D. Hynds; V. Iakovenko; P. Ilten; J. Imong; R. Jacobsson; A. Jaeger; M. Jahjah Hussein; E. Jans; F. Jansen; P. Jaton; B. Jean-Marie; F. Jing; M. John; D. Johnson; C. R. Jones; B. Jost; S. Kandybei; M. Karacson; T. M. Karbach; J. Keaveney; U. Kerzel; T. Ketel; A. Keune; B. Khanji; Y. M. Kim; M. Knecht; S. Koblitz; P. Koppenburg; A. Kozlinskiy; L. Kravchuk; K. Kreplin; M. Kreps; G. Krocker; P. Krokovny; F. Kruse; K. Kruzelecki; M. Kucharczyk; S. Kukulak; R. Kumar; T. Kvaratskheliya; V. N. La Thi; D. Lacarrere; G. Lafferty; A. Lai; D. Lambert; R. W. Lambert; E. Lanciotti; G. Lanfranchi; C. Langenbruch; T. Latham; R. Le Gac; J. van Leerdam; J.-P. Lees; R. Lefvre; A. Leflat; J. Lefranois; O. Leroy; T. Lesiak; L. Li; L. Li Gioi; M. Lieng; M. Liles; R. Lindner; C. Linn; B. Liu; G. Liu; J. H. Lopes; E. Lopez Asamar; N. Lopez-March; J. Luisier; F. Machefert; I. V. Machikhiliyan; F. Maciuc; O. Maev; J. Magnin; S. Malde; R. M. D. Mamunur; G Mancinelli; N. Mangiafave; U. Marconi; R. Mrki; J. Marks; G. Martellotti; A. Martens; L. Martin; A. Martn Snchez; D. Martinez Santos; A. Massafferri; R. Matev; Z. Mathe; C. Matteuzzi; M. Matveev; E. Maurice; B. Maynard; A. Mazurov; G. McGregor; R. McNulty; C. Mclean; M. Meissner; M. Merk; J. Merkel; R. Messi; S. Miglioranzi; D. A. Milanes; M.-N. Minard; S. Monteil; D. Moran; P. Morawski; I. Mous; F. Muheim; K. Mller; R. Muresan; B. Muryn; M. Musy; J. Mylroie-Smith; P. Naik; T. Nakada; R. Nandakumar; J. Nardulli; I. Nasteva; M Needham; N. Neufeld; C. Nguyen-Mau; M. Nicol; S. Nies; V. Niess; N. Nikitin; A. Oblakowska-Mucha; V. Obraztsov; S. Oggero; S. Ogilvy; O. Okhrimenko; R. Oldeman; M. Orlandea; J. M. Otalora Goicochea; P. Owen; B. Pal; J. Palacios; M. Palutan; J. Panman; A. Papanestis; M. Pappagallo; C J Parkinson; G. Passaleva; G. D. Patel; M. Patel; S. K. Paterson; G. N. Patrick; C Pavel-Nicorescu; A. Pazos Alvarez; A. Pellegrino; G. Penso

2011-01-01

262

Antifungal activity of tuberose absolute and some of its constituents.  

PubMed

The antifungal activity of the absolute of tuberose (Polianthes tuberosa ) and some of its constituents were evaluated against the mycelial growth of Colletotrichum gloeosporioides on potato-dextrose-agar medium. Tuberose absolute showed only mild activity at a concentration of 500 mg/L. However, three constituents present in the absolute, namely geraniol, indole and methyl anthranilate exhibited significant activity showing total inhibition of the mycelial growth at this concentration. PMID:16106389

Nidiry, Eugene Sebastian J; Babu, C S Bujji

2005-05-01

263

Phase Theory account of absolutive extraction in Tagalog  

Microsoft Academic Search

In Tagalog, and other syntactically ergative languages, only absolutive DPs are able to undergo A'-movement. This paper proposes a mechanism which correlates this restriction with absolutive case-checking within the theory of Multiple Spell-Out. I propose that T checks absolutive case only in intransitive clauses like antipassives, while v does so in transitive clauses. v is also able to host an

Edith Aldridge

264

Three-position absolute measurement simulation and error analysis  

Microsoft Academic Search

To meeting the testing requirements of high-precision optical surfaces, the absolute testing technology was used for the optical testing process. Three-Position absolute measurements with the advantage of few requested testing and testing conditions are often easily satisfaction were used to high-precision spherical surface shape testing. However in the error process of three-position absolute measurements, cat's position error has an important

Peng Yang; Fan Wu; Xi Hou

2011-01-01

265

Absolute Pitch in Infant Auditory Learning: Evidence for Developmental Reorganization  

Microsoft Academic Search

To what extent do infants represent the absolute pitches of complex auditory stimuli? Two experiments with 8-month-old infants examined the use of absolute and relative pitch cues in a tone-sequence statistical learning task. The results suggest that, given unsegmented stimuli that do not conform to the rules of musical composition, infants are more likely to track patterns of absolute pitches

Jenny R. Saffran; Gregory J. Griepentrog

2001-01-01

266

Gyrokinetic statistical absolute equilibrium and turbulence  

SciTech Connect

A paradigm based on the absolute equilibrium of Galerkin-truncated inviscid systems to aid in understanding turbulence [T.-D. Lee, Q. Appl. Math. 10, 69 (1952)] is taken to study gyrokinetic plasma turbulence: a finite set of Fourier modes of the collisionless gyrokinetic equations are kept and the statistical equilibria are calculated; possible implications for plasma turbulence in various situations are discussed. For the case of two spatial and one velocity dimension, in the calculation with discretization also of velocity v with N grid points (where N+1 quantities are conserved, corresponding to an energy invariant and N entropy-related invariants), the negative temperature states, corresponding to the condensation of the generalized energy into the lowest modes, are found. This indicates a generic feature of inverse energy cascade. Comparisons are made with some classical results, such as those of Charney-Hasegawa-Mima in the cold-ion limit. There is a universal shape for statistical equilibrium of gyrokinetics in three spatial and two velocity dimensions with just one conserved quantity. Possible physical relevance to turbulence, such as ITG zonal flows, and to a critical balance hypothesis are also discussed.

Zhu Jianzhou [Center for Multiscale Plasma Dynamics, University of Maryland, College Park, Maryland 20742-3511 (United States); Hammett, Gregory W. [Princeton Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, New Jersey 08543 (United States)

2010-12-15

267

Relative and Absolute Detection Efficiency of WWLLN  

NASA Astrophysics Data System (ADS)

A recent upgrade to the World Wide Lightning Location Network (WWLLN) allows for the network to measure the far-field VLF radiated power of the detected strokes, this is in addition to the network locating the strokes in space and time. The network consists of 57 VLF antennas spread around the globe and is able to accurately locate most strokes to within ~10km in space, <30?s in time and with an average of 20% uncertainty in power. The capability to measure the radiated stroke power has enabled a first principles based model of the global relative detection efficiency of the network. By utilizing past comparisons of WWLLN to other ground based networks the absolute detection efficiency of the network can be estimated for the entire globe. The results of the relative WWLLN detection efficiency model are used to show the global distribution of strokes as seen by the network if it had uniform global coverage. Similarly the effects of a single VLF detector going offline are investigated for the regimes of sparse and dense detector coverage. The results are also used to show spatial, temporal and power distributions as seen by the detection efficiency corrected WWLLN.

Hutchins, M. L.; Holzworth, R. H.; Rodger, C. J.; Brundell, J. B.; McCarthy, M.

2011-12-01

268

Absolute decay width measurements in 16O  

NASA Astrophysics Data System (ADS)

The reaction 126C(63Li, d)168O* at a 6Li bombarding energy of 42 MeV has been used to populate excited states in 16O. The deuteron ejectiles were measured using the high-resolution Munich Q3D spectrograph. A large-acceptance silicon-strip detector array was used to register the recoil and break-up products. This complete kinematic set-up has enabled absolute ?-decay widths to be measured with high-resolution in the 13.9 to 15.9 MeV excitation energy regime in 16O; many for the first time. This energy region spans the 14.4 MeV four-? breakup threshold. Monte-Carlo simulations of the detector geometry and break-up processes yield detection efficiencies for the two dominant decay modes of 40% and 37% for the ?+12C(g.s.) and a+12C(2+1) break-up channels respectively.

Wheldon, C.; Ashwood, N. I.; Barr, M.; Curtis, N.; Freer, M.; Kokalova, Tz; Malcolm, J. D.; Spencer, S. J.; Ziman, V. A.; Faestermann, Th; Krcken, R.; Wirth, H.-F.; Hertenberger, R.; Lutter, R.; Bergmaier, A.

2012-09-01

269

Absolute-convective instability of coaxial jets  

NASA Astrophysics Data System (ADS)

A well established route for the massive microencapsulation of labile materials, microorganisms, pharmaceutical principles, flavors, or any active ingredients of any kind involves the generation and breakup of coaxial capillary jets. Here, surface tension is the ultimate molding mechanism, and therefore experience teaches that the product quality is optimized within operating condition ranges where Weber and Capillary numbers attain limited values. These ranges allow for a precise control of the product structure. However, surface tension also mandates whether compound capillary jets may form or not: Weber and Capillary numbers maps exhibit ``hard'' boundaries where jets become locally unstable (absolutely unstable) as opposed to convectively unstable, and the product shows dramatic changes in structure (generally a degradation) across these boundaries. In this work we perform a linear spatiotemporal analysis of coaxial capillary jets to provide cartographic maps of viable regions in the Weber and Capillary numbers space. A discussion on the connection of these maps with the morphology of the resulting products is also given, together with comparisons with published experimental literature.

Ferrera, Conrado; Herrada, Miguel A.; Montanero, Jose M.; Ganan-Calvo, Alfonso M.

2008-11-01

270

The Absolute Parallaxes of Four Magnetic CVs  

NASA Astrophysics Data System (ADS)

We have an HST Cycle 9 and 10 program to measure the parallaxes of three magnetic cataclysmic variables (V1223 Sgr, EF Eri, and EX Hya). In addition, we had a Cycle 8 program that has successfully measured the relative parallax of TV Col. In our previous HST parallax program on three dwarf novae (Harrison et al. 1999), we found that the indirect distance estimation techniques failed to produce useful results. When we combined new infrared spectroscopy obtained using CRSP (on the KPNO 2.1 m) with the parallaxes and published optical/IR photometry, we found that the secondary stars in these three systems appeared to be too luminous for their observed spectral types. Our new program is designed to both determine if the secondary stars in magnetic systems are similarly unusual, as well as calorimeter the accretion rates in these four systems. To obtain accurate parallaxes, however, requires that we obtain the mean parallaxes of the reference frames. We request CTIO time to observe the reference stars of these four CV fields to obtain the necessary spectroscopy and photometry to determine the spectroscopic parallax of each reference star. We request two nights on the 0.9 m to obtain UBVRI photometry, and three nights on the 1.5 m to obtain optical spectroscopy for MK classification. We must know the mean parallaxes of the reference frames to determine the absolute parallaxes for these four CVs.

Harrison, Thomas E.; Beuermann, Klaus; Gansicke, Boris; Benedict, Fritz; McArthur, Barbara

2001-02-01

271

A Liquid-Helium-Cooled Absolute Reference Cold Load forLong-Wavelength Radiometric Calibration  

SciTech Connect

We describe a large (78-cm) diameter liquid-helium-cooled black-body absolute reference cold load for the calibration of microwave radiometers. The load provides an absolute calibration near the liquid helium (LHe) boiling point, accurate to better than 30 mK for wavelengths from 2.5 to 25 cm (12-1.2 GHz). The emission (from non-LHe temperature parts of the cold load) and reflection are small and well determined. Total corrections to the LHe boiling point temperature are {le} 50 mK over the operating range. This cold load has been used at several wavelengths at the South Pole and at the White Mountain Research Station. In operation, the average LHe loss rate was {le} 4.4 l/hr. Design considerations, radiometric and thermal performance and operational aspects are discussed. A comparison with other LHe-cooled reference loads including the predecessor of this cold load is given.

Bensadoun, M.; Witebsky, C.; Smoot, George F.; De Amici,Giovanni; Kogut, A.; Levin, S.

1990-05-01

272

Absolute calorimetric calibration of low energy brachytherapy sources  

NASA Astrophysics Data System (ADS)

In the past decade there has been a dramatic increase in the use of permanent radioactive source implants in the treatment of prostate cancer. A small radioactive source encapsulated in a titanium shell is used in this type of treatment. The radioisotopes used are generally 125I or 103Pd. Both of these isotopes have relatively short half-lives, 59.4 days and 16.99 days, respectively, and have low-energy emissions and a low dose rate. These factors make these sources well suited for this application, but the calibration of these sources poses significant metrological challenges. The current standard calibration technique involves the measurement of ionization in air to determine the source air-kerma strength. While this has proved to be an improvement over previous techniques, the method has been shown to be metrologically impure and may not be the ideal means of calbrating these sources. Calorimetric methods have long been viewed to be the most fundamental means of determining source strength for a radiation source. This is because calorimetry provides a direct measurement of source energy. However, due to the low energy and low power of the sources described above, current calorimetric methods are inadequate. This thesis presents work oriented toward developing novel methods to provide direct and absolute measurements of source power for low-energy low dose rate brachytherapy sources. The method is the first use of an actively temperature-controlled radiation absorber using the electrical substitution method to determine total contained source power of these sources. The instrument described operates at cryogenic temperatures. The method employed provides a direct measurement of source power. The work presented here is focused upon building a metrological foundation upon which to establish power-based calibrations of clinical-strength sources. To that end instrument performance has been assessed for these source strengths. The intent is to establish the limits of the current instrument to direct further work in this field. It has been found that for sources with powers above approximately 2 muW the instrument is able to determine the source power in agreement to within less than 7% of what is expected based upon the current source strength standard. For lower power sources, the agreement is still within the uncertainty of the power measurement, but the calorimeter noise dominates. Thus, to provide absolute calibration of lower power sources additional measures must be taken. The conclusion of this thesis describes these measures and how they will improve the factors that limit the current instrument. The results of the work presented in this thesis establish the methodology of active radiometric calorimetey for the absolute calibration of radioactive sources. The method is an improvement over previous techniques in that there is no reliance upon the thermal properties of the materials used or the heat flow pathways on the source measurements. The initial work presented here will help to shape future refinements of this technique to allow lower power sources to be calibrated with high precision and high accuracy.

Stump, Kurt E.

273

Observations of plasma wave turbulence generated around large ionospheric spacecraft: Effects of motionally induced EMF and of electron beam emission  

SciTech Connect

The authors report on observations of plasma wave turbulence generated during electron beam injections, spacecraft potential variations, and neutral gas emissions of the CHARGE 2 sounding rocket experiment. The payload was flown in a mother/daughter configuration, with the two sub-payloads electrically connected by an insulated, conducting tether. While tethered, the two platforms were separated, drifting apart in a direction perpendicular to both the magnetic field and to the spacecraft velocity, reaching a maximum distance of 426 m at the end of the flight. The mother carried a high-voltage (HV) system (0-460 V), biasing the mother negative relative to the daughter. The operation of the HV bias system simulated the motional emf induced in larger orbiting space structures like the Tethered Satellite System 1 (TSS 1) space shuttle mission scheduled for the spring of 1992. In addition, the mother carried an electron beam accelerator (1 keV, 0-46 mA). The daughter diagnostics included wave receivers (400 Hz to 10 MHz) connected to a pair of electric dipole antennas. Broadband ELF/VLF turbulence was generated both during electron beam emissions and when the HV bias system was operated, while turbulence in the HF range was observed only during electron beam emissions. As a result of the electrical connection through the tether, the ELF/VLF wave intensities show little variation with separation distance of the two payloads. Two sources of wave turbulence are proposed to account for the observations: (1) wave turbulence generated by the beam/spacecraft system in particular in the HF range, and (2) electron return currents to the daughter simulating VLF noise during HV operations and electron beam emissions.

Neubert, T.; Gilchrist, B.E.; Banks, P.M. (Univ. of Michigan, Ann Arbor (USA)); Sasaki, S. (Inst. for Space and Astronautical Sciences, Kanagawa (Japan)); Fraser-Smith, A.C. (Stanford Univ., CA (USA)); Raitt, W.J. (Utah State Univ., Logan (USA))

1991-06-01

274

Absolute Rovibrational Intensities for the Chi(sup 1)Sigma(sup +) v=3 <-- 0 Band of (12)C(16)O Obtained with Kitt Peak and BOMEM FTS Instruments.  

National Technical Information Service (NTIS)

This work was initiated to compare absolute line intensities retrieved with the Kitt Peak FTS (Fourier Transform Spectrometer) and Ames BOMEM FTS. Since thermal contaminations can be a problem using the BOMEM instrument if proper precautions are not taken...

C. Chackerian R. J. Kshirsagar L. P. Giver L. R. Brown

1999-01-01

275

Component mode synthesis for multibody systems with absolute coordinates  

Microsoft Academic Search

AbstractIn the present paper, the concept of the float- ing frame of reference is transformed to a description based on absolute coordinates. The equations are linearized for a certain configuration of the body based on a corotational strain tensor. Because of the transformation,to absolute coordinates, the mass matrix is constant and the stiffness matrix can be inverted efficiently. Pairs of

J. Gerstmayr

2007-01-01

276

On the Choice of Absolute or Relative Inequality Measures  

PubMed Central

Context: In a recent article in this journal, Sam Harper and his colleagues (2010) call for increased awareness and open dialogue of moral judgments underlying health inequality measures. They recommend that analysts use relative inequality measures when concerned only about health inequality but use absolute inequality measures when also concerned about other issues, such as the overall level of population health and the level of health for each group in the population. Methods: Using a simple, hypothetical example, this commentary shows that the relationships among inequality, the absolute level for each group, and the overall level in the population are more complex than suggested by the analysis by Harper and his colleagues. Findings: First, analysts must make the choice of absolute or relative inequality measures, separately, for single- and multiple-population cases. Second, in the single-population cases, analysts can use both relative and absolute inequality measures when concerned only about health inequality independent of other considerations. Third, in almost all real-world multiple-population cases, when using either the absolute or relative inequality measure, the assessment of health inequality is influenced by the absolute level of health for each group. Conclusions: The choice between absolute and relative inequality measures is not about the independent normative significance of inequality, as Harper and his colleagues suggest. In choosing between absolute and relative measures, future work needs to integrate an empirical examination of values, a moral assessment of values, and a technical understanding of inequality measures.

Asada, Yukiko

2010-01-01

277

Absolute electronegativity and hardness: application to inorganic chemistry  

Microsoft Academic Search

The recent concepts of absolute electronegativity, \\/chi\\/, and absolute hardness, \\/eta\\/, are briefly reviewed. The operational definitions, \\/chi\\/ = (I + A)\\/2 and \\/eta\\/ = (I - A)\\/2, are used to calculate experimental values for a large number of cations, atoms, radicals, and molecules. The resulting values are shown to be in good agreement with chemical behavior, both as to

Ralph G. Pearson

1988-01-01

278

Absolute Humidity and the Seasonality of Influenza (Invited)  

NASA Astrophysics Data System (ADS)

Much of the observed wintertime increase of mortality in temperate regions is attributed to seasonal influenza. A recent re-analysis of laboratory experiments indicates that absolute humidity strongly modulates the airborne survival and transmission of the influenza virus. Here we show that the onset of increased wintertime influenza-related mortality in the United States is associated with anomalously low absolute humidity levels during the prior weeks. We then use an epidemiological model, in which observed absolute humidity conditions temper influenza transmission rates, to successfully simulate the seasonal cycle of observed influenza-related mortality. The model results indicate that direct modulation of influenza transmissibility by absolute humidity alone is sufficient to produce this observed seasonality. These findings provide epidemiological support for the hypothesis that absolute humidity drives seasonal variations of influenza transmission in temperate regions. In addition, we show that variations of the basic and effective reproductive numbers for influenza, caused by seasonal changes in absolute humidity, are consistent with the general timing of pandemic influenza outbreaks observed for 2009 A/H1N1 in temperate regions. Indeed, absolute humidity conditions correctly identify the region of the United States vulnerable to a third, wintertime wave of pandemic influenza. These findings suggest that the timing of pandemic influenza outbreaks is controlled by a combination of absolute humidity conditions, levels of susceptibility and changes in population mixing and contact rates.

Shaman, J. L.; Pitzer, V.; Viboud, C.; Grenfell, B.; Goldstein, E.; Lipsitch, M.

2010-12-01

279

ABSOLUTE OPTICAL CALIBRATION USING A SIMPLE TUNGSTEN LIGHT BULB: EXPERIMENT  

Microsoft Academic Search

Absolute spectral intensity calibration of optical detectors has always been difficult. Up to now it was only possible through the use of expensive sources, which are cross-calibrated against national standards. At the 28AM optical meeting, a simple theoretical approach to absolute optical calibrations was described using any ordinary tungsten light bulb (1). A key element of the theory is transforming

M. J. Kosch; S. Mkinen; F. Sigernes; O. Harang

280

Comparison and Establishment of Three Absolute Plate Motion Models  

NASA Astrophysics Data System (ADS)

Three absolute models of plate motion: PRF - ITRF2000 derived from assumption that the Pacific ridge was fixed, HS2 - ITRF2000 based on the hotspot data, and NNR - ITRF2000 are presented in this paper. It is suggested that the PRF - ITRF2000 is probably an appropriate absolute reference frame.

Jin, Shuang-Gen; Zhu, Wen-Yao

2002-01-01

281

Robust Algorithm for Least Absolute Deviations Curve Fitting.  

National Technical Information Service (NTIS)

The least absolute deviations criterion, or the l1 norm, is frequently used for approximation where the data may contain outliers or wild points'. One of the most popular methods for solving the least absolute deviations data fitting problem is the Barrod...

D. Lei I. J. Anderson M. G. Cox

2001-01-01

282

Determination of Absolute Zero Using a Computer-Based Laboratory  

ERIC Educational Resources Information Center

We present a simple computer-based laboratory experiment for evaluating absolute zero in degrees Celsius, which can be performed in college and undergraduate physical sciences laboratory courses. With a computer, absolute zero apparatus can help demonstrators or students to observe the relationship between temperature and pressure and use

Amrani, D.

2007-01-01

283

Absolute Intensity Calibration of 1 M Ebert-Fastie Spectrometer.  

National Technical Information Service (NTIS)

An absolute intensity calibration of the 1 m Ebert-Fastie spectrometer in the wavelength region 300 to 800 nm was performed. As a calibration standard an absolutely calibrated quartz-halogen lamp and a freshly smoked Mg0 screen were used. A number of diff...

B. Nilsson J. Stegman

1983-01-01

284

Absolute and convective instabilities in plasmas and solids  

NASA Astrophysics Data System (ADS)

The theory of absolute and convective instabilities in plasmas and solids is examined. Criteria of the absolute and convective instabilities of spatial amplification are derived and used to analyze specific systems in various fields of physics. The systems examined include optical quantum generators, acoustic amplifiers, and acoustic generators, Gunn diode, TWT, BWT, and two-beam amplifiers.

Fedorchenko, A. M.; Kotsarenko, N. Ia.

285

Testing the quasi-absolute method in photon activation analysis  

NASA Astrophysics Data System (ADS)

In photon activation analysis (PAA), relative methods are widely used because of their accuracy and precision. Absolute methods, which are conducted without any assistance from calibration materials, are seldom applied for the difficulty in obtaining photon flux in measurements. This research is an attempt to perform a new absolute approach in PAA - quasi-absolute method - by retrieving photon flux in the sample through Monte Carlo simulation. With simulated photon flux and database of experimental cross sections, it is possible to calculate the concentration of target elements in the sample directly. The QA/QC procedures to solidify the research are discussed in detail. Our results show that the accuracy of the method for certain elements is close to a useful level in practice. Furthermore, the future results from the quasi-absolute method can also serve as a validation technique for experimental data on cross sections. The quasi-absolute method looks promising.

Sun, Z. J.; Wells, D.; Starovoitova, V.; Segebade, C.

2013-04-01

286

Thermal properties measurements in biodiesel oils using photothermal techniques  

NASA Astrophysics Data System (ADS)

In this Letter, thermal lens and open cell photoacoustic techniques are used to measure the thermal properties of biodiesel oils. The absolute values of the thermal effusivity, thermal diffusivity, thermal conductivity and the temperature coefficient of the refractive index were determined for samples obtained from soy, castor bean, sunflower and turnip. The results suggest that the employed techniques may be useful as complementary methods for biodiesel certification.

Castro, M. P. P.; Andrade, A. A.; Franco, R. W. A.; Miranda, P. C. M. L.; Sthel, M.; Vargas, H.; Constantino, R.; Baesso, M. L.

2005-08-01

287

Absolute cross sections for ({gamma},{ital n}) transitions in lead, bismuth, and terbium  

SciTech Connect

Absolute cross sections of ({gamma},{ital n}) transitions in lead, bismuth, and terbium were measured using thermal neutron capture photons, and a high resolution neutron spectrometer. The measured ({gamma},{ital n}) cross sections were compared with predictions of the Direct-Semi-Direct (DSD) and the compound nucleus (CN) models, and were found to be generally underestimated by the DSD calculations and closer to the predictions of the CN models. Some of the ({gamma},{ital n}) cross sections in lead and bismuth were found to be comparable in magnitude to the extrapolation from the tail of the giant dipole resonance.

Birenbaum, Y.; Berant, Z.; Kahane, S.; Wolf, A. [Physics Department, Nuclear Research Center-Negev, Beer-Sheva 84190 (Israel); Moreh, R. [Physics Department, Nuclear Research Center-Negev, Beer-Sheva 84190 (Israel)]|[Ben-Gurion University, Beer-Sheva 84120 (Israel)

1995-06-01

288

Study of BelousovZhabotinsky oscillators in wateracetonitrile medium employing EMF and EPR techniques with o-vanillin, p-vanillin and adrenaline as substrates  

NASA Astrophysics Data System (ADS)

The oscillatory behaviour of three substrates, ortho-vanillin, para-vanillin and adrenaline, in mixed media (water plus 20% acetonitrile) has been investigated using EPR and EMF techniques. All these substrates exhibit two types of oscillation involving Br 2/Br - and Mn(III)/Mn(II) redox couples. From the oscillatory characteristics (total time, number of oscillations and time per oscillation) obtained by employing these techniques, the reactivities of the vanillins have been correlated. The FieldKorosNoyes mechanism, suggested for catalysed systems in pure aqueous medium, is established to be applicable even in mixed media.

Lalitha, P. V.; Ramaswamy, R.; Ramakrishnan, Geetha; Rao, P. Sambasiva

1994-12-01

289

Absolute dose verifications in small photon fields using BANGTM gel  

NASA Astrophysics Data System (ADS)

Polymer gel dosimeters change their magnetic resonance (MR) and optical properties with the absorbed dose when irradiated and are suitable for narrow photon beam dosimetry in radiosurgery. Such dosimeters enable relative and absolute 3D dose verifications in order to check the entire treatment chain from imaging to dose application during commissioning and quality assurance. For absolute 3D dose verifications in radiosurgery using Gamma Knife B, commercially available BANGTM Gels (BANG 25 Gy and BANG 3 Gy) together with dedicated phantoms were chosen in order to determine the potential of absolute gel dosimetry in radiosurgery.

Scheib, S. G.; Schenkel, Y.; Gianolini, S.

2004-01-01

290

Measurement of Disintegration Rates and Absolute {gamma}-ray Intensities  

SciTech Connect

The majority of practical radioactive materials decay by modes that include {gamma}-ray emission. For questions of 'how much' or 'how pure', one must know the absolute intensities of the major radiations. We are using liquid scintillation counting (LSC) to measurements of disintegration rates, coupled with {gamma}-ray spectroscopy to measure absolute {gamma}-ray emission probabilities. Described is a study of the 227Th chain yielding absolute {gamma}-ray intensities with {approx}0.5% accuracy and information on LSC efficiencies.

DeVries, Daniel J.; Griffin, Henry C. [Department of Chemistry, University of Michigan, Ann Arbor, MI 48109 (United States)

2006-03-13

291

ABSOLUTE PROPERTIES OF THE ECCENTRIC ECLIPSING BINARY STAR FT ORIONIS  

SciTech Connect

Accurate absolute properties are determined for the first time for the 3.15 day period eccentric eclipsing binary star FT Ori based on new absolute photometry, five differential light curves, and a radial velocity curve. The stars appear to be normal for their spectral types, A0 + A2. The orbit is highly eccentric (e = 0.409) and shows apsidal motion with a period of 536 years. The absolute properties and the degree of central mass concentration of the stars are consistent with current theoretical models at an age of 190 Myr.

Sabby, Jeffrey A. [Physics Department, Southern Illinois University Edwardsville, Edwardsville, IL 62025 (United States); Lacy, Claud H. Sandberg [Physics Department, University of Arkansas, Fayetteville, AR 72701 (United States); Ibanoglu, Cafer [Astronomy and Space Sciences Department, Science Faculty, Ege University, 35100 Boronova, Izmir (Turkey); Claret, Antonio, E-mail: jsabby@siue.edu, E-mail: clacy@uark.edu, E-mail: cafer.ibanoglu@ege.edu.tr, E-mail: claret@iaa.es [Instituto de Astrofisica de Andalucia, CSIC, Apdo. Postal 3004, E-18080 Granada (Spain)

2011-06-15

292

Ab initio calculation of band absolute intensities in IR spectra  

NASA Astrophysics Data System (ADS)

Ab initio calculations in a harmonic approximation of absorption band absolute intensities in infrared spectra were carried out for 3 hydrocarbons and 14 halogenated hydrocarbons. The calculated data were compared with experimental values of the absolute absorption intensities. It is shown that a Hartree-Fock calculation method overestimates significantly (by an average of 66%) the integrated absolute intensities of the fundamental bands in the region 575-4000 cm-1. The deviation is reduced to 32% in the case of the MP2 method of accounting for electron correlations. Most of the overestimation occurs for bands corresponding to vibrations involving halogen atoms.

Pavlyuchko, A. I.; Vasilyev, E. V.; Gribov, L. A.

2012-01-01

293

An algorithm for estimating Absolute Salinity in the global ocean  

NASA Astrophysics Data System (ADS)

To date, density and other thermodynamic properties of seawater have been calculated from Practical Salinity, S P. It is more accurate however to use Absolute Salinity, S A (the mass fraction of dissolved material in seawater). Absolute Salinity S A can be expressed in terms of Practical Salinity S P as S A=(35.165 04 g kg-1/35)S P+? S A(?, ?, p) where ? S A is the Absolute Salinity Anomaly as a function of longitude ?, latitude ? and pressure. When a seawater sample has standard composition (i.e. the ratios of the constituents of sea salt are the same as those of surface water of the North Atlantic), the Absolute Salinity Anomaly is zero. When seawater is not of standard composition, the Absolute Salinity Anomaly needs to be estimated; this anomaly is as large as 0.025 g kg-1 in the northernmost North Pacific. Here we provide an algorithm for estimating Absolute Salinity Anomaly for any location (?, ?, p) in the world ocean. To develop this algorithm we use the Absolute Salinity Anomaly that is found by comparing the density calculated from Practical Salinity to the density measured in the laboratory. These estimates of Absolute Salinity Anomaly however are limited to the number of available observations (namely 811). To expand our data set we take advantage of approximate relationships between Absolute Salinity Anomaly and silicate concentrations (which are available globally). We approximate the laboratory-determined values of ? S A of the 811 seawater samples as a series of simple functions of the silicate concentration of the seawater sample and latitude; one function for each ocean basin. We use these basin-specific correlations and a digital atlas of silicate in the world ocean to deduce the Absolute Salinity Anomaly globally and this is stored as an atlas, ? S A (?, ?, p). This atlas can be interpolated to the latitude, longitude and pressure of a seawater sample to estimate its Absolute Salinity Anomaly. For the 811 samples studied, ignoring the Absolute Salinity Anomaly results in a standard error in S A of 0.0107 g kg-1. Using our algorithm for ? S A reduces the error to 0.0048 g kg-1, reducing the mean square error by a factor of five. The number of sea water samples used to develop the correlation relationship is limited, and we hope that the algorithm and error can be improved as further data becomes available.

McDougall, T. J.; Jackett, D. R.; Millero, F. J.

2009-02-01

294

An All Fiber White Light Interferometric Absolute Temperature Measurement System  

PubMed Central

Recently the author of this article proposed a new signal processing algorithm for an all fiber white light interferometer. In this article, an all fiber white light interferometric absolute temperature measurement system is presented using the previously proposed signal processing algorithm. Stability and absolute temperature measurement were demonstrated. These two tests demonstrated the feasibility of absolute temperature measurement with an accuracy of 0.015 fringe and 0.0005 fringe, respectively. A hysteresis test from 373K to 873K was also presented. Finally, robustness of the sensor system towards laser diode temperature drift, AFMZI temperature drift and PZT non-linearity was demonstrated.

Kim, Jeonggon Harrison

2008-01-01

295

Incorrect Weighting of Absolute Performance in Self-Assessment  

NASA Astrophysics Data System (ADS)

Students spend much of their life in an attempt to assess their aptitude for numerous tasks. For example, they expend a great deal of effort to determine their academic standing given a distribution of grades. This research finds that students use their absolute performance, or percentage correct as a yardstick for their self-assessment, even when relative standing is much more informative. An experiment shows that this reliance on absolute performance for self-evaluation causes a misallocation of time and financial resources. Reasons for this inappropriate responsiveness to absolute performance are explored.

Jeffrey, Scott A.; Cozzarin, Brian

296

The Seminole Serpent Warrior At Miramar, FL, Shows Settlement Locations Enabled Environmental Monitoring Reminiscent Of the Four-corners Kokopelli-like EMF Phenomena, and Related to Earthquakes, Tornados and Hurricanes.  

NASA Astrophysics Data System (ADS)

Certain Native Americans of the past seem to have correctly deduced that significant survival information for their tradition-respecting cultures resided in EMF-based phenomena that they were monitoring. This is based upon their myths and the place or cult-hero names they bequeathed us. The sites we have located in FL have been detectable by us visually, usually by faint blue light, or by the elicitation of pin-like prickings, by somewhat intense nervous-system response, by EMF interactions with aural electrochemical systems that can elicit tinitus, and other ways. In the northeast, Cautantowit served as a harbinger of Indian summer, and appears to be another alter ego of the EMF. The Miami, FL Tequesta site along the river clearly correlates with tornado, earthquake and hurricane locations. Sites like the Mohave Deserts giant man may have had similar significance.

Balam Matagamon, Chan; Pawa Matagamon, Sagamo

2004-03-01

297

EMF wire code research  

SciTech Connect

This paper examines the results of previous wire code research to determines the relationship with childhood cancer, wire codes and electromagnetic fields. The paper suggests that, in the original Savitz study, biases toward producing a false positive association between high wire codes and childhood cancer were created by the selection procedure.

Jones, T.

1993-11-01

298

Elucidating absolute configuration of unsaturated alcohols via enantioselective acylation reactions.  

PubMed

Enantioselective nucleophilic acylation catalysis provides a simple method of determining absolute configuration for unsaturated alcohols. Extension of this technique to natural products and synthetic compounds, as well as current limitations of this approach, are also described. PMID:23619624

LeGay, Christina M; Boudreau, Colton G; Derksen, Darren J

2013-04-25

299

Examining rounding error in least absolute values regression computations  

Microsoft Academic Search

Two techniques for detecting inaccuracies in least absolute values (LAV) regression computations are presented and discussed. Examples of the use of the methods are given. The techniques are shown to apply to the more general case of M-estimation.

W. J. Kennedy; James E. Gentle

1977-01-01

300

Absolute Magnitudes of Be Stars Based on Hipparcos Parallaxes  

NASA Astrophysics Data System (ADS)

The absolute visual magnitudes of 457 Be stars are determined from Hipparcos parallaxes, subsequently the mean absolute visual magnitudes of Be stars for luminosity classes III, IV and V are obtained. The new Mv calibration is compared with existing calibrations. It is found that Be stars are generally brighter than B stars of the corresponding spectral types, and that there is no direct correlation between absolute magnitudes and the stellar rotational velocity, these results are in agreement with some earlier results. A new and interesting result is that there is no direct correlation between near infrared excess and absolute visual magnitudes for Be stars. Moreover, possible biases, such as the Malmquist bias and the Lutz Kelker bias, are also discussed.

Zhang, P.; Liu, C. Q.; Chen, P. S.

2006-12-01

301

Probative value of absolute and relative judgments in eyewitness identification.  

PubMed

It is well-accepted that eyewitness identification decisions based on relative judgments are less accurate than identification decisions based on absolute judgments. However, the theoretical foundation for this view has not been established. In this study relative and absolute judgments were compared through simulations of the WITNESS model (Clark, Appl Cogn Psychol 17:629-654, 2003) to address the question: Do suspect identifications based on absolute judgments have higher probative value than suspect identifications based on relative judgments? Simulations of the WITNESS model showed a consistent advantage for absolute judgments over relative judgments for suspect-matched lineups. However, simulations of same-foils lineups showed a complex interaction based on the accuracy of memory and the similarity relationships among lineup members. PMID:20953683

Clark, Steven E; Erickson, Michael A; Breneman, Jesse

2011-10-01

302

Aristarchus Crater: Mapping of Impact Melt and Absolute Age Determination  

NASA Astrophysics Data System (ADS)

We report on progress made mapping Aristarchus Crater using high-resolution LROC NAC images. Observations include enigmatic impact melt features and stratified blocks of ejecta. An absolute model age using crater counts was also determined.

Zanetti, M.; Hiesinger, H.; van der Bogert, C. H.; Reiss, D.; Jolliff, B. L.

2011-03-01

303

Aristarchus Crater: Mapping of Impact Melt and Absolute Age Determination  

Microsoft Academic Search

We report on progress made mapping Aristarchus Crater using high-resolution LROC NAC images. Observations include enigmatic impact melt features and stratified blocks of ejecta. An absolute model age using crater counts was also determined.

M. Zanetti; H. Hiesinger; C. H. van der Bogert; D. Reiss; B. L. Jolliff

2011-01-01

304

Preparation of an oakmoss absolute with reduced allergenic potential.  

PubMed

Synopsis Oakmoss absolute, an extract of the lichen Evernia prunastri, is known to cause allergenic skin reactions due to the presence of certain aromatic aldehydes such as atranorin, chloratranorin, ethyl hematommate and ethyl chlorohematommate. In this paper it is shown that treatment of Oakmoss absolute with amino acids such as lysine and/or leucine, lowers considerably the content of these allergenic constituents including atranol and chloratranol. The resulting Oakmoss absolute, which exhibits an excellent olfactive quality, was tested extensively in comparative studies on guinea pigs and on man. The results of the Guinea Pig Maximization Test (GPMT) and Human Repeated Insult Patch Test (HRIPT) indicate that, in comparison with the commercial test sample, the allergenicity of this new quality of Oakmoss absolute was considerably reduced, and consequently better skin tolerance of this fragrance for man was achieved. PMID:19272096

Ehret, C; Maupetit, P; Petrzilka, M; Klecak, G

1992-06-01

305

Absolute pitch in infant auditory learning: evidence for developmental reorganization.  

PubMed

To what extent do infants represent the absolute pitches of complex auditory stimuli? Two experiments with 8-month-old infants examined the use of absolute and relative pitch cues in a tone-sequence statistical learning task. The results suggest that, given unsegmented stimuli that do not conform to the rules of musical composition, infants are more likely to track patterns of absolute pitches than of relative pitches. A 3rd experiment tested adults with or without musical training on the same statistical learning tasks used in the infant experiments. Unlike the infants, adult listeners relied primarily on relative pitch cues. These results suggest a shift from an initial focus on absolute pitch to the eventual dominance of relative pitch, which, it is argued, is more useful for both music and speech processing. PMID:11206435

Saffran, J R; Griepentrog, G J

2001-01-01

306

Methods of calibration of measuring installations containing an absolute blackbody  

NASA Astrophysics Data System (ADS)

A comparative analysis of methods of determination of irradiance values in the plane of location of sensitive elements (SE) of detectors in measuring installations containing an absolutely black body (ABB) was carried out.

Bakumenko, V. L.; Beguchev, V. P.; Degtjaryov, E. V.; Kozhanov, I. A.; Saginov, L. D.; Sviridov, A. N.

2005-06-01

307

Direct and absolute temperature mapping and heat transfer measurements in diode-end-pumped Yb:YAG  

Microsoft Academic Search

We report on direct and absolute temperature measurements in a diode-end-pumped Yb:YAG crystal, using a calibrated infrared camera, with a 60m spatial resolution. The heat transfer coefficient has been measured, for the first time to our knowledge, with four different types of thermal contact (H=0.25, 0.28, 0.9, and 2.0 for bare contact, graphite layer, indium foil, and heat sink grease

Sbastien Chnais; S. Forget; F. Druon; Francois Balembois; Patrick Georges

2004-01-01

308

The absolute configuration of cuauhtemone and related compounds  

Microsoft Academic Search

The absolute configuration of cuauhtemone, a eudesmane-type sesquiterpene isolated from Pluchea species (Asteraceae), has been revised from 1 to 2 by chemical correlation with (R)-(+)-2-methyl-1,2-butanediol 3 through the naturally occurring 2,3-epoxy-2-methylbutanoate derivative 4. The relative stereochemistry of 4 was confirmed by X-ray diffraction analysis. The obtained data are also useful for reconsideration of the absolute configurations of a relevant group

J. Mart??n Torres-Valencia; Dora L. Quintero-Mogica; Guadalupe I. Len; Oscar R. Surez-Castillo; J. Roberto Villagmez-Ibarra; Emma Maldonado; Carlos M. Cerda-Garc??a-Rojas; Pedro Joseph-Nathan

2003-01-01

309

Absolute flux measurement at HIGS using Compton backscattering  

Microsoft Academic Search

The High Intensity gamma-ray Source (HIgammaS) at FELL\\/TUNL is developing a program to study many aspects of nuclear physics presently using 2-to-50 MeV gamma-rays. In many cases these experiments require absolute gamma-flux monitoring and determination. This project presents a technique to indirectly measure the absolute gamma-ray flux by placing a thin scattering foil in the gamma-beam and then detecting the

B. Fallin; M. W. Ahmed; B. Perdue; A. Sabourov; T. Sheard; W. Tornow; A. P. Tonchev; H. R. Weller; J. Li; I. V. Pinaev; Y. Wu; R. M. Prior; M. Spraker; J. Chen; G. Feldman

2003-01-01

310

Absolutely Continuous Spectrum for Multi-type Galton Watson Trees  

NASA Astrophysics Data System (ADS)

We consider multi-type Galton Watson trees that are close to a tree of finite cone type in distribution. Moreover, we impose that each vertex has at least one forward neighbor. Then, we show that the spectrum of the Laplace operator exhibits almost surely a purely absolutely continuous component which is included in the absolutely continuous spectrum of the tree of finite cone type.

Keller, Matthias

2012-12-01

311

An algorithm for estimating Absolute Salinity in the global ocean  

Microsoft Academic Search

To date, density and other thermodynamic properties of seawater have been calculated from Practical Salinity, S P. It is more accurate however to use Absolute Salinity, S A (the mass fraction of dissolved material in seawater). Absolute Salinity S A can be expressed in terms of Practical Salinity S P as S A=(35.165 04 g kg-1\\/35)S P+delta S A(phi, lambda,

T. J. McDougall; D. R. Jackett; F. J. Millero

2009-01-01

312

Simone de Beauvoirs Ethics of Freedom and Absolute Evil  

Microsoft Academic Search

Simone de Beauvoir held that human experience is intrinsically ambiguous and that there are no values extrinsic to experience, but she also designated some actions as absolute evil. This essay explains how Beauvoir utilized an intrinsic absolute value to ground an action-guiding principle of freedom that justifies her notion of evil. Morgan’s analysis counters Robin May Schott’s objections that Beauvoir

Anne Morgan

2008-01-01

313

Absolute branching fraction measurements of exclusive D0 semileptonic decays.  

PubMed

With the first data sample collected by the CLEO-c detector at the psi(3770) resonance we have studied four exclusive semileptonic decays of the D0 meson. Our results include the first observation and absolute branching fraction measurement for D0 --> p-e+ve and improved measurements of the absolute branching fractions for D0 decays to K-e+ve, pi-e+ve, and K*-e+ve. PMID:16383893

Coan, T E; Gao, Y S; Liu, F; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Dambasuren, E; Dorjkhaidav, O; Li, J; Menaa, N; Mountain, R; Nandakumar, R; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Briere, R A; Chen, G P; Chen, J; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Crede, V; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gittelman, B; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krger, H; Meyer, T O; Onyisi, P U E; Patterson, J R; Peterson, D; Pivarski, J; Phillips, E A; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shepherd, M R; Stroiney, S; Sun, W M; Urner, D; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Patel, R; Potlia, V; Stoeck, H; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Gollin, G D; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; Williams, J; Wiss, J; Edwards, K W; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Kubota, Y; Klein, T; Lang, B W; Li, S Z; Poling, R; Scott, A W; Smith, A; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A; Zweber, P; Ernst, J; Mahmood, A H; Severini, H; Asner, D M; Dytman, S A; Love, W; Mehrabyan, S; Mueller, J A; Savinov, V; Li, Z; Lopez, A; Mendez, H; Ramirez, J; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shibata, E I; Shipsey, I P J; Adams, G S; Chasse, M; Cravey, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Muramatsu, H; Park, C S; Park, W; Thorndike, E H

2005-10-24

314

Investigations on DNA damage and frequency of micronuclei in occupational exposure to electromagnetic fields (EMFs) emitted from video display terminals (VDTs)  

PubMed Central

The potential effect of electromagnetic fields (EMFs) emitted from video display terminals (VDTs) to elicit biological response is a major concern for the public. The software professionals are subjected to cumulative EMFs in their occupational environments. This study was undertaken to evaluate DNA damage and incidences of micronuclei in such professionals. To the best of our knowledge, the present study is the first attempt to carry out cytogenetic investigations on assessing bioeffects in personal computer users. The study subjects (n = 138) included software professionals using VDTs for more than 2 years with age, gender, socioeconomic status matched controls (n = 151). DNA damage and frequency of micronuclei were evaluated using alkaline comet assay and cytochalasin blocked micronucleus assay respectively. Overall DNA damage and incidence of micronuclei showed no significant differences between the exposed and control subjects. With exposure characteristics, such as total duration (years) and frequency of use (minutes/day) sub-groups were assessed for such parameters. Although cumulative frequency of use showed no significant changes in the DNA integrity of the classified sub-groups, the long-term users (> 10 years) showed higher induction of DNA damage and increased frequency of micronuclei and micro nucleated cells.

2010-01-01

315

RELATIVE VERSUS ABSOLUTE STIMULUS CONTROL IN THE TEMPORAL BISECTION TASK  

PubMed Central

When subjects learn to associate two sample durations with two comparison keys, do they learn to associate the keys with the short and long samples (relational hypothesis), or with the specific sample durations (absolute hypothesis)? We exposed 16 pigeons to an ABA design in which phases A and B corresponded to tasks using samples of 1 s and 4 s, or 4 s and 16 s. Across phases, we varied the mapping between the samples and the keys. For group Relative, short and long samples were always associated with the same keys (e.g., Phase A: 1s? Left, 4s? Right'; Phase B: 4s? Left, 16s? Right'); for group Absolute, the 4-s sample was associated always with the same key (e.g., Phase A: 1s? Left, 4s? Right'; Phase B: 16s? Left, 4s? Right). If temporal control is relational, group Relative should learn the new task faster than group Absolute, but if temporal control is absolute, the opposite should occur. We compared the results with the predictions of the Learning-to-Time (LeT) model, which accounts for temporal discrimination in terms of absolute stimulus control and stimulus generalization. The acquisition curves of the two groups were generally consistent with LeT and therefore more consistent with the absolute than the relative hypothesis.

Pinheiro de Carvalho, Marilia; Machado, Armando

2012-01-01

316

On-Orbit Absolute Temperature Calibration Using Multiple Phase Change Materials  

NASA Astrophysics Data System (ADS)

NASAs anticipated plan for a mission dedicated to Climate (CLARREO) will hinge upon the ability to fly SI traceable standards that provide irrefutable absolute measurement accuracy. As an example, instrumentation designed to measure spectrally resolved infrared radiances will require high-emissivity calibration blackbodies that have absolute temperature uncertainties of better than 0.045K (3 sigma). A novel scheme to provide absolute calibration of temperature sensors, suitable for CLARREO on-orbit operation, has been demonstrated in the laboratory at the University of Wisconsin, and is now undergoing refinement under NASA Instrument Incubator Program funding. In this scheme, small quantities of reference materials (mercury, water, and gallium) are imbedded into the blackbody cavity wall, in a manner similar to the temperature sensors to be calibrated. As the blackbody cavity is slowly heated through the melt point of each reference material, the transient temperature signature from the imbedded thermistor sensors provides a very accurate indication of the melt temperature. Using small quantities of phase change material (less than half of a percent of the mass of the cavity), melt temperature accuracies of better than 10 mK have been demonstrated for mercury, water, and gallium (providing calibration from 233K to 303K). Refinements currently underway focus on ensuring that the melt materials in their sealed confinement housings perform as expected in the thermal and microgravity environment of a multi-year spaceflight mission. Thermal soak and cycling tests are underway to demonstrate that there is no dissolution from the housings into the melt materials that could alter melt temperature, and that there is no liquid metal embrittlement of the housings from the metal melt materials. In addition, NASA funding has been recently secured to conduct a demonstration of this scheme in the microgravity environment of the International Space Station.

Best, F. A.; Adler, D. P.; Pettersen, C.; Revercomb, H. E.; Perepezko, J. H.

2009-12-01

317

Absolute Neutron Emission Measurement in Burning Plasma Experiments  

SciTech Connect

The absolute measurement of neutron emission rate from the whole plasma is a very important diagnostics as a fusion power monitor in fusion experimental devices with D-T or D-T operations. Here measurement techniques of time-resolved and time-integrated absolute neutron emission on the present tokamaks and ITER are reviewed. In the present tokamaks, fission chamber installed outside the vacuum vessel are very popular in the absolute neutron emission rate measurement. As well as conventional neutron monitors installed outside the vacuum vessel, in-vessel neutron monitors using micro fission chamber are proposed for the absolute neutron emission rate measurement in ITER. The neutron activation system provides time-integrated measurements of the total neutron yield with high accuracy by using well known neutron reaction cross sections, which is useful to maintain a robust measure of fusion energy production with stability and wide dynamic range. The calibration of the relation between the neutron emission rate in the whole plasma and the output of neutron monitor is the most important issue in the absolute neutron emission rate measurements. The calibration of the neutron detectors has been performed by moving a neutron source such as a {sup 252}Cf neutron or a small accelerator-based neutron generator. For the calibration in ITER, the neutron generator with neutron emission rate of 10{sup 11} s{sup -1} or stronger is required to obtain high accuracy.

Nishitani, Takeo; Ishikawa, Masao; Kondoh, Takashi; Kusama, Yoshinori [Japan Atomic Energy Agency, Naka, Ibaraki-ken, 311-0193 (Japan); Asai, Keisuke [Nagoya University, Chikusa-ku, Nagoya, 464-8603 (Japan); Sasao, Mmamiko [Tohoku University, Aoba-ku, Sendai, 980-8579 (Japan)

2008-03-12

318

Absolute irradiance of the Moon for on-orbit calibration  

USGS Publications Warehouse

The recognized need for on-orbit calibration of remote sensing imaging instruments drives the ROLO project effort to characterize the Moon for use as an absolute radiance source. For over 5 years the ground-based ROLO telescopes have acquired spatially-resolved lunar images in 23 VNIR (Moon diameter ???500 pixels) and 9 SWIR (???250 pixels) passbands at phase angles within ??90 degrees. A numerical model for lunar irradiance has been developed which fits hundreds of ROLO images in each band, corrected for atmospheric extinction and calibrated to absolute radiance, then integrated to irradiance. The band-coupled extinction algorithm uses absorption spectra of several gases and aerosols derived from MODTRAN to fit time-dependent component abundances to nightly observations of standard stars. The absolute radiance scale is based upon independent telescopic measurements of the star Vega. The fitting process yields uncertainties in lunar relative irradiance over small ranges of phase angle and the full range of lunar libration well under 0.5%. A larger source of uncertainty enters in the absolute solar spectral irradiance, especially in the SWIR, where solar models disagree by up to 6%. Results of ROLO model direct comparisons to spacecraft observations demonstrate the ability of the technique to track sensor responsivity drifts to sub-percent precision. Intercomparisons among instruments provide key insights into both calibration issues and the absolute scale for lunar irradiance.

Stone, T. C.; Kieffer, H. H.

2002-01-01

319

Absolute and relative family affluence and psychosomatic symptoms in adolescents.  

PubMed

Previous research on the links between income inequality and health and socioeconomic differences in health suggests that relative differences in affluence impact health and well-being more than absolute affluence. This study explored whether self-reported psychosomatic symptoms in adolescents relate more closely to relative affluence (i.e., relative deprivation or rank affluence within regions or schools) than to absolute affluence. Data on family material assets and psychosomatic symptoms were collected from 48,523 adolescents in eight countries (Austria, Belgium, Canada, Norway, Scotland, Poland, Turkey, and Ukraine) as part of the 2009/10 Health Behaviour in School-aged Children study. Multilevel regression analyses of the data showed that relative deprivation (Yitzhaki Index, calculated in regions and in schools) and rank affluence (in regions) (1) related more closely to symptoms than absolute affluence, and (2) related to symptoms after differences in absolute affluence were held constant. However, differences in family material assets, whether they are measured in absolute or relative terms, account for a significant variation in adolescent psychosomatic symptoms. Conceptual and empirical issues relating to the use of material affluence indices to estimate socioeconomic position are discussed. PMID:23849235

Elgar, Frank J; De Clercq, Bart; Schnohr, Christina W; Bird, Phillippa; Pickett, Kate E; Torsheim, Torbjrn; Hofmann, Felix; Currie, Candace

2013-05-10

320

Design and fabrication of a microplatform for the proximity effect study of localized ELF-EMF on the growth of in vitro HeLa and PC-12 cells  

NASA Astrophysics Data System (ADS)

This paper presents a platform technology with experimental results that show the scientists and biologists a way to rapidly investigate and analyze the biological effects of localized extremely low frequency (ELF) electromagnetic field (EMF) on living cells. The proximity effect of the localized ELF-EMF on living cells is revealed using the bio-compatible microplatform on which an on-glass inductive coil array, the source of the localized ELF-EMF in micro scale, is designed, fabricated and operated with a field strength of 1.2 0.1 mT at 60 Hz for cell culturing study. After a 72 h ELF-EMF exposure, HeLa (human cervical cancer) and PC-12 (rat pheochromocytoma) cells exhibit about 18.4% and 12.9% cell proliferation rate reduction, respectively. Furthermore, according to the presented dynamic model, the reduction of the proliferation can be attributed to the interference of signal transduction processes due to the tangential currents induced around the cells.

Chen, Y. C.; Chen, C. C.; Tu, W.; Cheng, Y. T.; Tseng, F. G.

2010-12-01

321

Optimized absolute testing method of shift-rotation.  

PubMed

The absolute testing method of shift-rotation that combines the traditional N-position method and Zernike polynomial fitting has been commonly employed in surface metrology. It preserves the high spatial frequency of the surface deviation with the N-position method to obtain the rotationally asymmetric surface deviation, but it suffers the kN? order angular terms errors missed by the N-position method when it calculates the rotationally symmetric surface deviation with the Zernike rotationally symmetric polynomial fitting method. An optimized absolute testing method of shift-rotation is presented in this paper. It considers the missing kN? order errors when the equations of the rotationally symmetric surface deviation are solved. As a result, it is more accurate than the traditional method. Experimental absolute results of spherical surfaces are given. PMID:24085219

Song, Weihong; Wu, Fan; Hou, Xi; Wan, Yongjian

2013-10-01

322

Absolute electron scattering cross sections for the CF2 radical.  

PubMed

Using a crossed electron-molecular beam experiment, featuring a skimmed nozzle beam with pyrolytic radical production, absolute elastic cross sections for electron scattering from the CF2 molecule have been measured. A new technique for placing measured cross sections on an absolute scale is used for molecular beams produced as skimmed supersonic jets. Absolute differential cross sections for CF2 are reported for incident electron energies of 30-50 eV and over an angular range of 20-135 deg. Integral cross sections are subsequently derived from those data. The present data are compared to new theoretical predictions for the differential and integral scattering cross sections, as calculated with the Schwinger multichannel variational method using the static-exchange and static-exchange plus polarization approximations. PMID:18352469

Maddern, Todd M; Hargreaves, Leigh R; Francis-Staite, Jessica R; Brunger, Michael J; Buckman, Stephen J; Winstead, Carl; McKoy, Vincent

2008-02-14

323

Method for estimating absolute lung volumes at constant inflation pressure.  

PubMed

A method has been devised for measuring functional residual capacity in the intact killed animal or absolute lung volumes in any excised lung preparation without changing the inflation pressure. This is achieved by titrating the absolute pressure of a chamber in which the preparation is compressed until a known volume of air has entered the lungs. This technique was used to estimate the volumes of five intact rabbit lungs and five rigid containers of known dimensions by means of Boyle's law. Results were found to agree to within +/- 1% with values determined by alternative methods. In the discussion the advantage of determining absolute lung volumes at almost any stage in a study of lung mechanics without the determination itself changing inflation pressure and, hence, lung volume is emphasized. PMID:511699

Hills, B A; Barrow, R E

1979-10-01

324

The Absolute Gravimeter FG5 - Adjustment and Residual Data Evaluation  

NASA Astrophysics Data System (ADS)

The most widely used method of direct terrestrial gravity determination is performed by using a ballistic absolute gravimeter. Today, the FG5 (Micro-g LaCoste; Lafayette, CO) is the most common free-fall absolute gravimeter. It uses the Michelson-type interferometer to determine the absolute gravity value with accuracies up to one part- per-billion of g. Furthermore, absolute gravimeter measurements can be used to assist in the validation and interpretation of temporal variations of the global gravity field, e.g. from the GRACE mission. In addition, absolute gravimetry allows for monitoring gravity changes which are caused by subsurface mass redistributions and/or vertical displacements. In this study,adjustment software was developed and applied to the raw data sets of FG5#106 and FG5#236, made available by Natural Resources Canada. Both data sets have been collected at the same time and place which leads to an intercomparison of the instruments performance. The adjustment software was validated against the official FG5 software package developed by Micro-g Lacoste. In order to identify potential environmental or instrument disturbances in the observed time series, a Lomb- Scargle periodogram analysis was employed. The absolute gravimeter FG5 is particularly sensitive to low frequencies between 0-3Hz. Hence, the focus of the analysis is to detect signals in the band of 0-100 Hz. An artificial signal was added to the measurements for demonstration purposes. Both the performance of the adjustment software and the Lomb-Scargle analysis will be discussed.

Orlob, M.; Braun, A.; Henton, J.; Courtier, N.; Liard, J.

2009-05-01

325

Neural Sensitivity to Absolute and Relative Anticipated Reward in Adolescents  

PubMed Central

Adolescence is associated with a dramatic increase in risky and impulsive behaviors that have been attributed to developmental differences in neural processing of rewards. In the present study, we sought to identify age differences in anticipation of absolute and relative rewards. To do so, we modified a commonly used monetary incentive delay (MID) task in order to examine brain activity to relative anticipated reward value (neural sensitivity to the value of a reward as a function of other available rewards). This design also made it possible to examine developmental differences in brain activation to absolute anticipated reward magnitude (the degree to which neural activity increases with increasing reward magnitude). While undergoing fMRI, 18 adolescents and 18 adult participants were presented with cues associated with different reward magnitudes. After the cue, participants responded to a target to win money on that trial. Presentation of cues was blocked such that two reward cues associated with $.20, $1.00, or $5.00 were in play on a given block. Thus, the relative value of the $1.00 reward varied depending on whether it was paired with a smaller or larger reward. Reflecting age differences in neural responses to relative anticipated reward (i.e., reference dependent processing), adults, but not adolescents, demonstrated greater activity to a $1 reward when it was the larger of the two available rewards. Adults also demonstrated a more linear increase in ventral striatal activity as a function of increasing absolute reward magnitude compared to adolescents. Additionally, reduced ventral striatal sensitivity to absolute anticipated reward (i.e., the difference in activity to medium versus small rewards) correlated with higher levels of trait Impulsivity. Thus, ventral striatal activity in anticipation of absolute and relative rewards develops with age. Absolute reward processing is also linked to individual differences in Impulsivity.

Vaidya, Jatin G.; Knutson, Brian; O'Leary, Daniel S.; Block, Robert I.; Magnotta, Vincent

2013-01-01

326

The IUE Absolute Flux Scale (Gonzalez-Riestra+, 2001)  

NASA Astrophysics Data System (ADS)

Tables tablea1 to tablea6 show the absolute fluxes of the IUE standard stars used for the derivation of the cameras Inverse Sensitivity Curves for the IUE Final Archive. The relative fluxes of the standard stars have been derived with the WD model, and the zero point of the scale has been set by OAO-2 observations. These fluxes define the absolute flux scale of IUE. Table tableb1 contains the model fluxes of the White Dwarf G191 B2B scaled to the OAO-2 flux scale. (7 data files).

Gonzalez-Riestra, R.; Cassatella, A.; Wamsteker, W.

2001-05-01

327

Test of relative and absolute price efficiency in regulated utilities  

SciTech Connect

A model for testing all types of relative price inefficiency expands the Averch-Johnson effect and makes it possible to test for absolute price efficiency, which exists if the value of the marginal product for each factor is equated to factor price and implies both cost minimization and production of the optimal quantity of output. Duality theory is used to derive the empirical model using 1973 data for electric utilities. The results indicate that relative and absolute price efficiency were generally not achieved by electric utilities in that year. 36 references, 1 table.

Atkinson, S.E.; Halvorsen, R.

1980-02-01

328

Nonexistence of equilibrium states at absolute negative temperatures  

NASA Astrophysics Data System (ADS)

We show that states of macroscopic systems with purported absolute negative temperatures are not stable under small, yet arbitrary, perturbations. We prove the previous statement using the fact that, in equilibrium, the entropy takes its maximum value. We discuss that, while Ramsey theoretical reformulation of the second law for systems with negative temperatures is logically correct, it must be a priori assumed that those states are in thermodynamic equilibrium. Since we argue that those states cannot occur, reversible processes are impossible, and, thus, Ramsey identification of absolute negative temperatures is untenable.

Romero-Rochn, Vctor

2013-08-01

329

Absolute branching fraction measurements of exclusive D+ semileptonic decays.  

PubMed

Using data collected at the psi(3770) resonance with the CLEO-c detector at the Cornell e+e- storage ring, we present improved measurements of the absolute branching fractions of D+decays to K0e+ve, pi0e+ve, K*0e+ve, and p0e+ve, and the first observation and absolute branching fraction measurement of D+ --> omega e+ve. We also report the most precise tests to date of isospin invariance in semileptonic D0 and D+ decays. PMID:16383892

Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shipsey, I P J; Adams, G S; Chasse, M; Cravey, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Muramatsu, H; Park, C S; Park, W; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Dambasuren, E; Dorjkhaidav, O; Li, J; Menaa, N; Mountain, R; Nandakumar, R; Randrianarivony, K; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Briere, R A; Chen, G P; Chen, J; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Crede, V; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gittelman, B; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krger, H; Meyer, T O; Onyisi, P U E; Patterson, J R; Peterson, D; Phillips, E A; Pivarski, J; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shi, X; Shepherd, M R; Stroiney, S; Sun, W M; Urner, D; Weaver, K M; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Patel, R; Potlia, V; Stoeck, H; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Gollin, G D; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; Williams, J; Wiss, J; Edwards, K W; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Li, S Z; Poling, R; Scott, A W; Smith, A; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A; Zweber, P; Ernst, J; Mahmood, A H; Severini, H; Asner, D M; Dytman, S A; Love, W; Mehrabyan, S; Mueller, J A; Savinov, V; Li, Z; Lopez, A; Mendez, H; Ramirez, J

2005-10-24

330

Remote absolute phase measurement in buried cable systems  

SciTech Connect

The paper presents a method for determining in underground distribution cable systems both phase sequence and absolute phase with respect to a standard which is broadcast over the power company`s cellular-telephone network. The method solves the problem of access to the cable center conductor by using a tool developed by the authors for non-destructive cable status testing. The paper presents some applications in distribution system maintenance and expansion. Limits to the accuracy of absolute phase measurement are discussed.

Horwitz, J. [Accelerated Systems, Danvers, MA (United States); Feldman, J. [Northeastern Univ., Boston, MA (United States). Electrical and Computer Engineering Dept.; Damrell, C.B. [Boston Edison Co., MA (United States); Reinhardt, N.

1995-01-01

331

A very fast and accurate rigorous EMF simulator for EUVL masks based on the pseudo-spectral time-domain method  

NASA Astrophysics Data System (ADS)

Computer simulation can be very useful for developing a better understanding of the printability of buried defects in EUVL masks. At present, the most widely used rigorous methods for this purpose are the finite-difference time-domain (FDTD) and the rigorous coupled wave analysis (RCWA) methods. However, both of these methods require huge computation resources to simulate large 3D EUVL masks accurately. In this paper, a new rigorous EMF simulator based on the pseudo-spectral time-domain (PSTD) method is discussed. PSTD is free from the grid-snapping and numerical-dispersion errors that plague FDTD and has an accuracy equal to that of RCWA. Also, PSTD requires relatively little computer memory and, furthermore, is well suited to parallization on both multi-core CPU and multi-GPU platforms.

Yeung, Michael; Barouch, Eytan

2013-06-01

332

Determination of torque speed current characteristics of a brushless DC motor by utilizing back-EMF of non-energized phase  

NASA Astrophysics Data System (ADS)

This paper presents a method to determine the torque constant and the torque speed current characteristics of a brushless DC (BLDC) motor by utilizing back-EMF variation of nonenergized phase. It also develops a BLDC motor controller with a digital signal processor (DSP) to monitor its current, voltage and speed in real time. Torque speed current characteristics of a BLDC motor are determined by using the proposed method and the developed controller. They are compared with the torque speed current characteristics measured by dynamometer experimentally. This research shows that the proposed method is an effective method to determine the torque constant and the torque speed current characteristics of the BLDC motor without using dynamometer.

Jang, G. H.; Yeom, J. H.; Kim, M. G.

2007-03-01

333

Influence of Inner Transducer Properties on EMF Response and Stability of Solid-Contact Anion Selective Membrane Electrodes Based on Metalloporphyrin Ionophores  

PubMed Central

The performance of solid-contact/coated wire type electrodes with plasticized PVC membranes containing metalloporphyrins as anion selective ionophores is reported. The membranes are deposited on transducers based on graphite pastes and graphite rods. The hydrophobicity of the underlying conductive transducer surface is found to be a key factor that influences the formation of an aqueous layer beneath the polymer film. Elimination of this ill-defined water layer greatly improves the electrochemical properties of the ion-sensors, such as EMF stability and life-time. Only highly lipophilic electrode substrates, namely graphite paste with mineral oil, were shown to prevent the formation of aqueous layer underneath the ion-sensing membrane. The possibility of employing Co(III)-tetraphenylporphyrin both as NO2? selective ionophore and as electron/ion conducting species to ensure ion-to-electron translation was also discussed based on the results of preliminary experiments.

Gorski, Lukasz; Matusevich, Alexey; Pietrzak, Mariusz; Wang, Lin; Meyerhoff, Mark E.; Malinowska, Elzbieta

2010-01-01

334

Proteomics of human primary osteoarthritic chondrocytes exposed to extremely low-frequency electromagnetic fields (ELF EMFs) and to therapeutic application of musically modulated electromagnetic fields (TAMMEF).  

PubMed

Abstract Osteoarthritis (OA) is the most frequent joint disease, characterized by degradation of extracellular matrix and alterations in chondrocyte metabolism. Some authors reported that electromagnetic fields (EMFs) can positively interfere with patients affected by OA, even though the nature of the interaction is still debated. Human primary osteoarthritic chondrocytes isolated from the femoral heads of OA-patients undergoing to total hip replacement, were cultured in vitro and exposed 30?min/day for two weeks to extremely-low-frequency electromagnetic field (ELF) with fixed frequency (100?Hz) and to therapeutic application of musically modulated electromagnetic fields (TAMMEF) with variable frequencies, intensities and waveforms. Sham-exposed (S.E.) cells served as control group. Cell viability was measured at days 2, 7 and 14. After two weeks, cell lysates were processed using a proteomic approach. Chondrocyte exposed to ELF and TAMMEF system demonstrated different viability compared to untreated chondrocytes (S.E.). Proteome analysis of 2D-Electrophoresis and protein identification by mass spectrometry showed different expression of proteins derived from nucleus, cytoplasm and organelles. Function analysis of the identified proteins showed changes in related-proteins metabolism (glyceraldeyde-3-phosphate-dehydrogenase), stress response (Mn-superoxide-dismutase, heat-shock proteins), cytoskeletal regulation (actin), proteinase inhibition (cystatin-B) and inflammation regulatory functions (S100-A10, S100-A11) among the experimental groups (ELF, TAMMEF and S.E.). In conclusion, EMFs do not cause damage to chondrocytes, besides stimulate safely OA-chondrocytes and are responsible of different protein expression among the three groups. Furthermore, protein analysis of OA-chondrocytes treated with ELF and the new TAMMEF systems could be useful to clarify the pathogenetic mechanisms of OA by identifying biomarkers of the disease. PMID:23713417

Corallo, Claudio; Battisti, Emilio; Albanese, Antonietta; Vannoni, Daniela; Leoncini, Roberto; Landi, Giacomo; Gagliardi, Assunta; Landi, Claudia; Carta, Serafino; Nuti, Ranuccio; Giordano, Nicola

2013-05-28

335

Thermal expansion and kinetic coefficients of crystals  

Microsoft Academic Search

Electrical (?) and thermal (W) resistivities and thermal expansion coefficient (?) of Cu, Zn, Al, Pb, Ni, ?-brass, Al2O3, NaCl, Si, SiO2(?), and SiO2(?) were simultaneously measured with standard four-probe, absolute steady-state, and quartz dilatometer techniques. Measurements of Ni and ?-brass were performed at temperatures from 300 to 1100K and measurements of all other samples were made between 90 and

I. M. Abdulagatov; Zh. Kh. Murlieva; D. K. Palchaev; K. K. Kazbekov; M. M. Maangalov

2007-01-01

336

Thermal expansion and kinetic coefficients of crystals  

Microsoft Academic Search

Electrical (rho) and thermal (W) resistivities and thermal expansion coefficient (beta) of Cu, Zn, Al, Pb, Ni, beta-brass, Al2O3, NaCl, Si, SiO2(||), and SiO2(?) were simultaneously measured with standard four-probe, absolute steady-state, and quartz dilatometer techniques. Measurements of Ni and beta-brass were performed at temperatures from 300 to 1100 K and measurements of all other samples were made between 90

I. M. Abdulagatov; Zh. Kh. Murlieva; D. K. Palchaev; K. K. Kazbekov; M. M. Maangalov

2007-01-01

337

Fabricating the Absolute Fake : America in Contemporary Pop Culture  

Microsoft Academic Search

Onze wereld wordt gedomineerd door de Amerikaanse popcultuur. Fabricating the Absolute Fake onderzoekt de dynamiek van Amerikanisering aan de hand van hedendaagse films, televisieprogramma's en popsterren die reflecteren op de vraag wat het betekent om Amerikaan in een mondiale popcultuur te zijn. Jaap Kooijman analyseert zowel Amerikaanse popcultuur (Oprah Winfrey, Ally McBeal, Michael Jackson) als Nederlandse populaire cultuur (Ali B.,

Jaap Kooijman

2008-01-01

338

Norm inequalities for the absolute value of Hilbert space operators  

Microsoft Academic Search

We use norm inequalities for operators, such as CauchySchwarz inequality and Minkowski inequality, to establish sharp norm inequalities for the absolute value of operators. Among other inequalities, it is shown that if A, B and X are operators on a Hilbert space, such that X is self-adjoint, and r ? 1, then This inequality generalizes some earlier related results. Other

Khalid Shebrawi; Hussien Albadawi

2010-01-01

339

Median filter with absolute value norm spatial regularization  

Microsoft Academic Search

We provide a novel formulation for computing median filter with spatial regularization as minimizing a cost function composed of absolute value norms. We turn this cost minimization into an equivalent linear programming (LP) and solve its dual LP as a minimum cost flow (MCF) problem. The MCF is solved over a graph constructed for an input image, and the primal

Nilanjan Ray

2011-01-01

340

Absolute activity measurement of radon gas at IRA-METAS  

Microsoft Academic Search

This paper describes the system of the Swiss national metrological institute (IRA-METAS) for the absolute standardisation of radon gas. This method relies on condensing radon under vacuum conditions within a specified cold area using a cryogenerator, and detecting its alpha particles with an ion-implanted silicon detector, through a very accurately defined solid angle. The accuracy of this defined solid angle

Philippe Spring; Youcef Nedjadi; Claude Bailat; Gilles Triscone; Franois Bochud

2006-01-01

341

Measurement of Absolute Vehicle Speed With a Simplified Inverse Model  

Microsoft Academic Search

This paper presents the study of a sensing technique for the measurement of the absolute speed of railway vehicles, which is achieved by detecting the time shift of the track random excitations between two wheelsets of a bogie (or truck). A simplified inverse model is designed to extract particular features of motion at the wheelsets from two inertial sensors mounted

T. X. Mei; H. Li

2010-01-01

342

Absolute configuration of amino alcohols by 1H-NMR.  

PubMed

A general NMR spectroscopy protocol for determination of absolute configuration of 1,2-amino alcohols, that allows differentiation of the four possible stereoisomers by analysis of the 1H NMR spectra of their bis-MPA derivatives, is described. PMID:16358061

Leiro, Victoria; Freire, Flix; Quio, Emilio; Riguera, Ricardo

2005-10-06

343

Absolute Stereochemistry of Chiral C 60 Fullerene Bis-Adducts  

Microsoft Academic Search

To determine the absolute configuration of chiral fullerene bis-adducts, we have studied the double Bingel reaction of C 60 with chiral tether (2 S ,3 S )-( m )- 9 derived from ( R , R )-(+)-tartaric acid, and have succeeded in isolating two possible chiral bis-adducts 10a (5%) and 10b (2%) in addition to the C s -symmetrically added

Kazuhiro Yoshida; Shuichi Osawa; Kenji Monde; Masataka Watanabe; Nobuyuki Harada

2002-01-01

344

The absolute configuration of (+)- and (-)-erythro-mefloquine.  

PubMed

The controversy over the absolute configuration of (+)-erythro-mefloquine, the less psychosis-causing enantiomer of the anti-malarial drug Lariam, has been resolved by Mosher ester crystallization. The configuration determined previously by physical methods is correct, whereas the configuration determined by three enantioselective syntheses is wrong. PMID:23616269

Mller, Michael; Orben, Claudia M; Schtzenmeister, Nina; Schmidt, Manuel; Leonov, Andrei; Reinscheid, Uwe M; Dittrich, Birger; Griesinger, Christian

2013-04-24

345

Estimation of the absolute surface air temperature of the Earth  

NASA Astrophysics Data System (ADS)

Average temperatures for the hemispheres and the globe are generally expressed as anomalies from a base period. Most users of these data and the underlying constituent gridded datasets do not require the values in absolute degrees, but a number of users might require this additional detail. An example group of users are climate modellers, who want to directly compare their simulations with reality in absolute units. Reanalysis datasets offer opportunities of assessing earlier absolute temperature estimates, but until recently their quality over data-sparse regions of the world was questionable. Here, we assess the latest Reanalysis (ERA-Interim) which is available from 1979 to the present against earlier direct estimates. Globally averaged ERA-Interim and the earlier direct estimates of absolute surface temperatures across the world are about 0.55C different for the 1981-2010 period, with ERA-Interim cooler. The difference is only 0.29C for the Northern Hemisphere, but larger at 0.81C for the Southern Hemisphere. Spatially, the largest differences come from the Polar Regions, particularly the Antarctic.

Jones, P. D.; Harpham, C.

2013-04-01

346

Absolute limit on rotation of gravitationally bound stars.  

National Technical Information Service (NTIS)

The authors seek an absolute limit on the rotational period for a neutron star as a function of its mass, based on the minimal constraints imposed by Einstein's theory of relativity, Le Chatelier's principle, causality and a low-density equation of state,...

N. K. Glendenning

1994-01-01

347

Absolute calibration of Landsat instruments using the moon.  

USGS Publications Warehouse

A lunar observation by Landsat could provide improved radiometric and geometric calibration of both the Thematic Mapper and the Multispectral Scanner in terms of absolute radiometry, determination of the modulation transfer function, and sensitivity to scattered light. A pitch of the spacecraft would be required. -Authors

Kieffer, H. H.; Wildey, R. L.

1985-01-01

348

Space solar patrol absolute measurements of ionizing solar radiation  

Microsoft Academic Search

In 1996 - 2003 the experiment Space Solar Patrol has been built for permanent absolute measurements of the ionizing solar radiation from the full disk of the Sun. Every 72 seconds the solar spectrum from 0.14 nm to 198 nm will be recorded with the resolution of <1.0 nm. The Space Solar Patrol mission consists of the Radiometer and the

S. Avakyan

2004-01-01

349

Absolute negative conductivity of graphene with impurities in magnetic field  

SciTech Connect

Current-voltage and current-field characteristics for graphene with Anderson interaction of conduction and impurity electrons are calculated by the 'average electron' method in the case of low temperatures. These characteristics are analyzed depending on the frequency of an external ac electric field and a magnetic field. A portion with absolute negative conductivity is detected.

Belonenko, M. B. [Volgograd Institute of Business, Laboratory of Nanotechnologies (Russian Federation); Lebedev, N. G.; Yanyushkina, N. N., E-mail: yana@inbox.ru [Volgograd State University (Russian Federation); Shakirzyanov, M. M. [Russian Academy of Sciences, Zavoisky Physicotechnical Institute, Kazan Scientific Center (Russian Federation)

2011-05-15

350

Absolute Temperature Monitoring Using RF Radiometry in the MRI Scanner  

Microsoft Academic Search

Temperature detection using microwave radiometry has proven value for noninvasively measuring the absolute temperature of tissues inside the body. However, current clinical radiometers operate in the gigahertz range, which limits their depth of penetration. We have designed and built a noninvasive radiometer which operates at radio frequencies (64 MHz) with ~100-kHz bandwidth, using an external RF loop coil as a

A.-M. M. El-Sharkawy; Paul P. Sotiriadis; Paul A. Bottomley; Ergin Atalar

2006-01-01

351

An integrated absolute temperature sensor with digital output  

Microsoft Academic Search

A smart temperature sensor is described which provides a pulse rate output and is highly suitable for communication with microprocessors. The temperature sensor generates an absolute-temperature current as well as a temperature-independent reference current. The fully synchronized output signal offers important advantages over asynchronous signals, such as frequency or duty cycle, which are often used. A high digital interference rejection

F. R. Riedijk; J. H. Huijsing

1991-01-01

352

An absolute zero of temperature: Locke's enunciation of the concept  

Microsoft Academic Search

Attention is drawn to a clear statement of the concept of an absolute zero of temperature by John Locke some time between 1698 and 1704. From the writings of Boyle and Newton it seems unlikely that either of them was responsible for providing their friend with this insight.

B. R. Coles

1995-01-01

353

Absolute Time and Temperature in Quantum and Classical Relativistic Mechanics  

Microsoft Academic Search

We present a relativistic quantum mechanics of a point mass with absolute thermodynamic time and temperature, combined to a single complex parameter of evolution. In this theory, the geometric time is introduced as one of space-time coordinates; it does not coincide with the thermodynamic time on the kinematical level. It is established, that the theory allows a consistent dynamics with

Vadim V. Asadov; Oleg V. Kechkin

2007-01-01

354

High accuracy measuring method of absolute temperatures using thermistors  

Microsoft Academic Search

High accuracy measuring techniques presuppose a high standard of quality of all components of a system. Here, the author shows how thermistors are well-suited as resistance sensors for high precision temperature measurements. Multislope analog to digital converters with very high resolution in connection with compensation methods result in the exact determination of absolute temperatures

V. Hans

1992-01-01

355

Torsion wave diffraction by an absolutely rigid body  

Microsoft Academic Search

An approximate method is proposed in this paper for the solution of axisymmetric stationary torsion wave scattering problems by absolutely rigid mobile and fixed inclusions of different shape imbedded in an elastic space. The method is based on applying solutions with a singularity of the type of a center of rotation which are distributed over a segment of the axis

V. A. Starikov

1984-01-01

356

Double Porosity Models for Absolutely Rigid Body via Reiterated Homogenization  

Microsoft Academic Search

Double porosity models for the liquid filtration in an absolutely rigid body is derived from homogenization theory. The governing equations of the fluid dynamics on the microscopic level consist of the Stokes system for a slightly compressible viscous fluid, occupying a crack -- pore space. In turn, this domain is a union of two independent systems of cracks (fissures) and

Anvarbek Meirmanov

2009-01-01

357

Absolute Pitch: Effects of Timbre on Note-Naming Ability  

Microsoft Academic Search

Background: Absolute pitch (AP) is the ability to identify or produce isolated musical tones. It is evident primarily among individuals who started music lessons in early childhood. Because AP requires memory for specific pitches as well as learned associations with verbal labels (i.e., note names), it represents a unique opportunity to study interactions in memory between linguistic and nonlinguistic information.

Patrcia Vanzella; E. Glenn Schellenberg; Dorothy Bishop

2010-01-01

358

Do individuals with Williams syndrome possess absolute pitch?  

Microsoft Academic Search

Although absolute pitch (AP) is a rare skill in typical development, individuals with Williams syndrome (WS) are often referred to as possessing this musical ability. However, there is paucity of research on the topic. In this article, 2 studies were conducted to evaluate AP in WS. In Study 1, seven musically trained individuals with WS, 14 musically trained typically developing

Pastora Martnez-Castilla; Mara Sotillo; Ruth Campos

2011-01-01

359

Optical fibre based absolute extrinsic Fabry - Prot interferometric sensing system  

Microsoft Academic Search

The design and principle of operation of a novel fibre optic sensing system is presented. The absolute extrinsic Fabry - Prot interferometric (AEFPI) system is shown to possess high sensitivity, wide dynamic range and a real-time output signal. Applications of the AEFPI system to high-performance civil structures are suggested. Multiplexing of many such sensors is achieved by employing the path

Vikram Bhatia; Kent A. Murphy; Richard O. Claus; Mark E. Jones; Jennifer L. Grace; Tuan A. Tran; Jonathan A. Greene

1996-01-01

360

An inverse method for estimating absolute velocities of the Kuroshio  

Microsoft Academic Search

An inverse method for estimating absolute velocities of the Kuroshio in the East China Sea and south of Japan was applied using hydrographic section data collected from January 19 to February 27 2006. By assuming the water mass to be conserved in four computational boxes, an undetermined system of linear equations was built. A family of solutions was firstly obtained

Bo Li; Xiao-Hua Zhu

2011-01-01

361

Measurement of the (sup 235) U absolute activity.  

National Technical Information Service (NTIS)

The absolute activity of (sup 235) U contained in a sample was measured utilizing a sum-coincidence circuit which selects only the alpha particles emitted simultaneously with the 143 KeV gamma radiations from the (sup 231) Th (product nucleus). The alpha ...

C. C. Bueno M. D. S. Santos

1993-01-01

362

Absolute Interrogative Intonation Patterns in Buenos Aires Spanish  

ERIC Educational Resources Information Center

In Spanish, each uttered phrase, depending on its use, has one of a variety of intonation patterns. For example, a phrase such as "Maria viene manana" "Mary is coming tomorrow" can be used as a declarative or as an absolute interrogative (a yes/no question) depending on the intonation pattern that a speaker produces. Patterns of usage also

Lee, Su Ar

2010-01-01

363

Determination of absolute right ascensions with small transit instruments  

Microsoft Academic Search

A method is proposed for the determination of stellar absolute right ascensions for studies of earth rotation by the use of small transit instruments. The method involves the simultaneous solution by the least squares method of the differential observation equation for each observatory of a group involved in the observing program. The solution of the equations is simplified by the

S. A. Tolchelnikova-Murri; E. I. Kreinin

1980-01-01

364

High precision levelling supporting the International Comparison of Absolute Gravimeters  

Microsoft Academic Search

High precision levelling is an indispensable method used to monitor benchmark and terrain stability at the Bureau International des Poids et Mesures (BIPM). Associated with the International Comparison of Absolute Gravimeters (ICAG), levelling measurements were carried out repeatedly over the past decades. A local gravity field strongly depends on vertical terrain deformation. 1 cm displacement implies about 2 Gal change

Z Jiang; M Becker; P Jousset; A Coulomb; L Tisserand; P Boulanger; D Lequin; F Lhermitte; J L Houillon; F Dupont

2012-01-01

365

Misalignment model used in three-position absolute measurement  

Microsoft Academic Search

Interferometric measurement, as dominating testing methods, is widely used in the field of optical measurement. Conventional interferometer subjects to many factors which make the measurement accuracy between lambda\\/10 and lambda\\/20, so it's difficult to meet the surface testing requirements of high accuracy. Thus the three-position absolute measurement technique is used to remove the errors which are introduced by reference surface

Peng Yang; Fan Wu; Xi Hou

2010-01-01

366

A Method for Measuring Absolute Reactor Power through Neutron Fluctuation  

Microsoft Academic Search

A new principle is presented for obtaining absolute reactor power by processing the random fluctuation of neutron flux based on the stochastic nature of nuclear reactions. The required combination of instruments to carry out experiments is described, and experimental results obtained in a swimming pool reactor are reported. The power spectral density of the output current of an ion chamber

Eiji SUZUKI

1966-01-01

367

Four Years of Absolute Gravity in the Taiwan Orogen (AGTO)  

NASA Astrophysics Data System (ADS)

AGTO is a scientific project between Taiwanese and French institutes, which aim is to improve tectonic knowledge of Taiwan primarily using absolute gravity measurements and permanent GPS stations. Both tools are indeed useful to study vertical movements and mass transfers involved in mountain building, a major process in Taiwan located at the convergent margin between Philippine Sea plate and Eurasian plate. This convergence results in two subductions north and south of Taiwan (Ryukyu and Manilla trenches, respectively), while the center is experiencing collision. These processes make Taiwan very active tectonically, as illustrated by numerous large earthquakes and rapid uplift of the Central Range. High slopes of Taiwan mountains and heavy rains brought by typhoons together lead to high landslides and mudflows risks. Practically, absolute gravity measurements have been yearly repeated since 2006 along a transect across south Taiwan, from Penghu to Lutao islands, using FG5 absolute gravimeters. This transect contains ten sites for absolute measurements and has been densified in 2008 by incorporating 45 sites for relative gravity measurements with CG5 gravimeters. The last relative and absolute measurements have been performed in November 2009. Most of the absolute sites have been measured with a good accuracy, about 1 or 2 ?Gal. Only the site located in Tainan University has higher standard deviation, due to the city noise. We note that absolute gravity changes seem to follow a trend in every site. However, straightforward tectonic interpretation of these trends is not valuable as many non-tectonic effects are supposed to change g with time, like groundwater or erosion. Estimating and removing these effects leads to a tectonic gravity signal, which has theoretically two origins : deep mass transfers around the site and vertical movements of the station. The latter can be well constrained by permanent GPS stations located close to the measurement pillar. Deep mass transfers, on the contrary, must be evaluated by modelling. Relative gravity, despite lower accuracy, enable us to cover wider area (about 10 000 km2). Our interest is thus to merge both types of measurements to have a large overview of temporal g changes in the south of Taiwan.

Mouyen, Maxime; Masson, Frdric; Hwang, Cheinway; Cheng, Ching-Chung; Le Moigne, Nicolas; Lee, Chiung-Wu; Kao, Ricky; Hsieh, Nicky

2010-05-01

368

How Accurately can we Calculate Thermal Systems?  

Microsoft Academic Search

I would like to determine how accurately a variety of neutron transport code packages (code and cross section libraries) can calculate simple integral parameters, such as K{sub eff}, for systems that are sensitive to thermal neutron scattering. Since we will only consider theoretical systems, we cannot really determine absolute accuracy compared to any real system. Therefore rather than accuracy, it

D Cullen; R N Blomquist; C Dean; D Heinrichs; M A Kalugin; M Lee; Y Lee; R MacFarlan; Y Nagaya; A Trkov

2004-01-01

369

Development of a phase-sensitive absolute radiometer for space and ground-based use  

NASA Astrophysics Data System (ADS)

Absolute radiometers with a phase-sensitive signal analysis are already being used in space successfully (Lawrence et al. (2000)). These instruments are operated with relatively long shutter periods of several minutes. Unfortunately, they have a large thermal capacity and are rather large and heavy and are therefore unsuitable for use on space missions where there is only a limited amount of load capacity available. The aim of our project is to develop a radiometer with a relatively small cavity and thermal capacity, which is based on phase-sensitive signal analysis as well, and which will have a much better accuracy than traditional instruments. With the help of the phase-sensitive analysis, many thermal sources of irritation, such as the so-called non-equivalence of the electric and radiative heating, can be eliminated. We hope to be able to run a radiometer experiment on both Solar Orbiter and Solar Dynamic Observatory (SDO) spacecraft, where the main advantage of reduced weight comes in. As a side effect, radiometers with small shutter periods are suitable for ground-based use as well, as they can handle fast changes in irradiance, i.e. altitude of the sun.

Schlifkowitz, Uwe; Finsterle, Wolfgang; Schmutz, Werner

2005-08-01

370

A new Ultra Precision Interferometer for absolute length measurements down to cryogenic temperatures  

NASA Astrophysics Data System (ADS)

A new Ultra Precision Interferometer (UPI) was built at Physikalisch-Technische Bundesanstalt. As its precursor, the precision interferometer, it was designed for highly precise absolute length measurements of prismatic bodies, e.g. gauge blocks, under well-defined temperature conditions and pressure, making use of phase stepping imaging interferometry. The UPI enables a number of enhanced features, e.g. it is designed for a much better lateral resolution and better temperature stability. In addition to the original concept, the UPI is equipped with an external measurement pathway (EMP) in which a prismatic body can be placed alternatively. The temperature of the EMP can be controlled in a much wider range compared to the temperature of the interferometer's main chamber. An appropriate cryostat system, a precision temperature measurement system and improved imaging interferometry were established to permit absolute length measurements down to cryogenic temperature, demonstrated for the first time ever. Results of such measurements are important for studying thermal expansion of materials from room temperature towards less than 10 K.

Schdel, R.; Walkov, A.; Zenker, M.; Bartl, G.; Mee, R.; Hagedorn, D.; Gaiser, C.; Thummes, G.; Heltzel, S.

2012-09-01

371

The University of Wisconsin Space Science and Engineering Center Absolute Radiance Interferometer (ARI): Radiometric Performance  

NASA Astrophysics Data System (ADS)

Spectrally resolved thermal radiances measured from orbit with extremely high absolute accuracy (< 0.1 K, k = 3, brightness temperature at scene temperature) constitute a critical observation for future climate benchmark missions. The FTS approach is well suited for the combined requirement of ultra high accuracy and broad spectral coverage at high spectral resolution. FTS technology inherently provides broad spectral coverage with a small number of detectors, a very well defined instrument line shape (ILS) that can be easily monitored and measured, and the spectral resolution required for accurate line shape and position determination and to accurately calibrate the spectral scale using well-known atmospheric absorption lines. The challenge in the IR FTS sensor development for a climate benchmark measurement mission is to achieve this ultra-high accuracy with a design that can be flight qualified, has long design life, and is reasonably small, simple, and affordable. In this area, our approach is to make use of components with strong spaceflight heritage (direct analogs with high TRL) combined into a functional package for detailed performance testing. The required simplicity is achievable due to the large differences in the sampling and noise requirements for the benchmark climate measurement from those of the typical remote sensing infrared sounders for weather research or operations. A summary of the radiometric performance of the Absolute Radiance Interferometer (ARI) at the University of Wisconsin Space Science and Engineering Center (UW-SSEC) will be presented.

Taylor, J. K.; Revercomb, H. E.; Buijs, H.; Grandmont, F. J.; Gero, P.; Best, F. A.; Tobin, D. C.; Knuteson, R.; LaPorte, D. D.

2011-12-01

372

Risk Factor Modification and Projections of Absolute Breast Cancer Risk  

PubMed Central

Background Although modifiable risk factors have been included in previous models that estimate or project breast cancer risk, there remains a need to estimate the effects of changes in modifiable risk factors on the absolute risk of breast cancer. Methods Using data from a casecontrol study of women in Italy (2569 case patients and 2588 control subjects studied from June 1, 1991, to April 1, 1994) and incidence and mortality data from the Florence Registries, we developed a model to predict the absolute risk of breast cancer that included five non-modifiable risk factors (reproductive characteristics, education, occupational activity, family history, and biopsy history) and three modifiable risk factors (alcohol consumption, leisure physical activity, and body mass index). The model was validated using independent data, and the percent risk reduction was calculated in high-risk subgroups identified by use of the Lorenz curve. Results The model was reasonably well calibrated (ratio of expected to observed cancers = 1.10, 95% confidence interval [CI] = 0.96 to 1.26), but the discriminatory accuracy was modest. The absolute risk reduction from exposure modifications was nearly proportional to the risk before modifying the risk factors and increased with age and risk projection time span. Mean 20-year reductions in absolute risk among women aged 65 years were 1.6% (95% CI = 0.9% to 2.3%) in the entire population, 3.2% (95% CI = 1.8% to 4.8%) among women with a positive family history of breast cancer, and 4.1% (95% CI = 2.5% to 6.8%) among women who accounted for the highest 10% of the total population risk, as determined from the Lorenz curve. Conclusions These data give perspective on the potential reductions in absolute breast cancer risk from preventative strategies based on lifestyle changes. Our methods are also useful for calculating sample sizes required for trials to test lifestyle interventions.

Decarli, Adriano; Schairer, Catherine; Pfeiffer, Ruth M.; Pee, David; Masala, Giovanna; Palli, Domenico

2011-01-01

373

The EM-POGO: A simple, absolute velocity profiler  

NASA Astrophysics Data System (ADS)

Electromagnetic current instrumentation has been added to the Bathy Systems, Inc. POGO transport sondes to produce a free-falling absolute velocity profiler called EM-POGO. The POGO is a free-fall profiler that measures a depth-averaged velocity using GPS fixes at the beginning and end of a round trip to the ocean floor (or a preset depth). The EM-POGO adds a velocity profile determined from measurements of motionally induced electric fields generated by the ocean current moving through the vertical component of the Earth's magnetic field. In addition to providing information about the vertical structure of the velocity, the depth-dependent measurements improve transport measurements by correcting for the non-constant fall-rate. Neglecting the variable fall rate results in errors O (1 cm s-1). The transition from POGO to EM-POGO included electrically isolating the POGO and electric-field-measuring circuits, installing a functional GPS receiver, finding a pressure case that provided an optimal balance among crush-depth, price and size, and incorporating the electrodes, electrode collar, and the circuitry required for the electric field measurement. The first EM-POGO sea-trial was in July 1999. In August 2006 a refurbished EM-POGO collected 15 absolute velocity profiles; relative and absolute velocity uncertainty was 1cms-1 and 0.5-5 cm s-1, respectively, at a vertical resolution of 25 m. Absolute velocity from the EM-POGO compared to shipboard ADCP measurements differed by 1-2 cm s-1, comparable to the uncertainty in absolute velocity from the ADCP. The EM-POGO is thus a low-cost, easy to deploy and recover, and accurate velocity profiler.

Terker, S. R.; Sanford, T. B.; Dunlap, J. H.; Girton, J. B.

2013-01-01

374

Precision absolute measurements of the radiation flux from the discrete sources Taurus-A and Cassiopeia-A and of the atmospheric absorption of radio waves at ?=5.28 cm  

Microsoft Academic Search

Results are given of absolute measuremenes of the ~adio flux from the discrete sources Taurus-A and Cassiopeia-A at a wavelength of k = 5,28 era. A precision method based on a comparison with the thermal radiation from an absolutely black disk placed in the Frauahofer region of the antenna was used. The fluxes were (6.46  0.3) X X 10

D. A. Dmitrenko; K. M. Strezhneva

1967-01-01

375

Absolute rate constant for the reaction of diphenylcarbene with C[sub 60  

SciTech Connect

In the present work, laser flash photolysis (LFP) technique has been used to measure the absolute rate constant for the reaction of Ph[sub 2]C: with C[sub 60]. This reaction represents the overall process of inflation of buckminsterfullerene C[sub 60] to fulleroid Ph[sub 2]C[sub 61]n. Results of the study show that it is possible that the absorption signal observed following LFP of Ph[sub 2]CN[sub 2] in the presence of C[sub 60], is due to the initial cyclopropane adduct formed by carbene addition; however, the typical instability of norcaradienes and the spectral similarities with the thermally generated product of Ph[sub 2]CN[sub 2] and C[sub 60] strongly suggest that the absorption signal observed following LFP is that of the fulleroid Ph[sub 2]C[sub 61]. 18 refs., 2 figs.

Chateauneuf, J.E. (Univ. of Notre Dame, IN (United States))

1995-03-08

376

Absolute Current Calibrations of 1muA CW Electron Beam  

SciTech Connect

The future experimental program at Jefferson Lab requires an absolute current calibration of a 1{mu}A CW electron beam to better than 1% accuracy. This paper presents the mechanical and electrical design of a Tungsten calorimeter that is being constructed to provide an accurate measurement of the deposited energy. The energy is determined by measuring the change in temperature after beam exposure. Knowledge of the beam energy then yields number of electrons stopped by the calorimeter during the exposure. Simulations show that the energy losses due to electromagnetic and hadronic losses are the dominant uncertainty. Details of the precision thermometry and calibration, mechanical design, thermal simulations and GEANT simulations will be presented.

A. Freyberger, M.E. Bevins, A.R. Day, P. Degtiarenko, A. Saha, S. Slachtouski, R. Gilman

2005-06-06

377

Measurement of the thermal conductivity of two coal liquids from ambient conditions to 220 C and 136 ATM  

Microsoft Academic Search

This paper describes thermal conductivity data obtained for two well characterized coal liquids using a new transient hot wire thermal conductivity instrument. The instrument clearly has the resolution to measure differences in liquid phase thermal conductivity due to the liquid's compressibility. The thermal conductivity measurements are absolute, and the instrument has been verified by a thorough study of toluene from

R. Perkins; M. S. Graboski; E. D. Sloan

1983-01-01

378

Thermal quenching of the fluorescence quantum efficiency in colquiriite crystals measured by thermal lens spectrometry  

NASA Astrophysics Data System (ADS)

The dual-beam mode-mismatched thermal lens technique was used to study the temperature dependence of the absolute fluorescence quantum efficiency (?) of a thermal-quenching fluorescence (TQF) process in Cr3+-doped colquiriite crystals (LiSAF and LiSGaF), from 300 to 450 K. The research was developed at a low excitation-power level in order to eliminate the energy-transfer upconversion effect. The results showed that TQF is the main loss mechanism involved. The thermal diffusivity, the thermal conductivity, and the specific heat of the samples were also measured in the same temperature range.

Pilla, Viviane; Catunda, Tomaz; Lima, Sandro Marcio; Medina, Antonio Neto; Baesso, Mauro Luciano; Jenssen, Hans P.; Cassanho, Arlete

2004-10-01

379

Thermal Sensing.  

National Technical Information Service (NTIS)

In thermal sensing devices, such as for calorimetry, a support layer or central layer can have a thermometer element or other thermal sensor on one side and a thermally conductive structure or component on the other. The thermally conductive structure can...

D. De Bruyker F. E. Torres M. V. Wolkin R. H. Bruce

2005-01-01

380

Absolute calibration for a broad range single shot electron spectrometer  

NASA Astrophysics Data System (ADS)

This article gives a detailed description of a single shot electron spectrometer which was used to characterize electron beams produced by laser-plasma interaction. Contrary to conventional electron sources, electron beams from laser-plasma accelerators can produce a broad range of energies. Therefore, diagnosing these electron spectra requires specific attention and experimental development. Here, we provide an absolute calibration of the Lanex Kodak Fine screen on a laser-triggered radio frequency picosecond electron accelerator. The efficiency of scintillating screens irradiated by electron beams has never been investigated so far. This absolute calibration is then compared to charge measurements from an integrating current transformer for quasimonoenergetic electron spectra from laser-plasma interaction.

Glinec, Y.; Faure, J.; Guemnie-Tafo, A.; Malka, V.; Monard, H.; Larbre, J. P.; de Waele, V.; Marignier, J. L.; Mostafavi, M.

2006-10-01

381

Absolute charge calibration of scintillating screens for relativistic electron detection  

NASA Astrophysics Data System (ADS)

We report on new charge calibrations and linearity tests with high-dynamic range for eight different scintillating screens typically used for the detection of relativistic electrons from laser-plasma based acceleration schemes. The absolute charge calibration was done with picosecond electron bunches at the ELBE linear accelerator in Dresden. The lower detection limit in our setup for the most sensitive scintillating screen (KODAK Biomax MS) was 10 fC/mm2. The screens showed a linear photon-to-charge dependency over several orders of magnitude. An onset of saturation effects starting around 10-100 pC/mm2 was found for some of the screens. Additionally, a constant light source was employed as a luminosity reference to simplify the transfer of a one-time absolute calibration to different experimental setups.

Buck, A.; Zeil, K.; Popp, A.; Schmid, K.; Jochmann, A.; Kraft, S. D.; Hidding, B.; Kudyakov, T.; Sears, C. M. S.; Veisz, L.; Karsch, S.; Pawelke, J.; Sauerbrey, R.; Cowan, T.; Krausz, F.; Schramm, U.

2010-03-01

382

Validation of GOCE by absolute and relative gravimetry  

NASA Astrophysics Data System (ADS)

Absolute gravimetry has been performed in 2011 by FG5 and A10 instruments in selected sites of the Norwegian first order gravity network. These observations are used as reference values to transform a large number of relative gravity values collected in 1968-1972. The outcome is a database at current epoch in a reference frame defined by the absolute gravity values. This constitutes our test field for validation of GOCE results. In the test fields, validation of GOCE-derived gravity anomalies was performed. The spectral enhancement method was applied to avoid the spectral inconsistency between the terrestrial and the satellite data. For this purpose, contributions of the EGM2008 model and a gravitational effect of a residual terrain model were calculated.

Pettersen, B. R.; Sprlak, M.; Lysaker, D. I.; Omang, O. C. D.; Sekowski, M.; Dykowski, P.

2012-04-01

383

Self consistent, absolute calibration technique for photon number resolving detectors.  

PubMed

Well characterized photon number resolving detectors are a requirement for many applications ranging from quantum information and quantum metrology to the foundations of quantum mechanics. This prompts the necessity for reliable calibration techniques at the single photon level. In this paper we propose an innovative absolute calibration technique for photon number resolving detectors, using a pulsed heralded photon source based on parametric down conversion. The technique, being absolute, does not require reference standards and is independent upon the performances of the heralding detector. The method provides the results of quantum efficiency for the heralded detector as a function of detected photon numbers. Furthermore, we prove its validity by performing the calibration of a Transition Edge Sensor based detector, a real photon number resolving detector that has recently demonstrated its effectiveness in various quantum information protocols. PMID:22109203

Avella, A; Brida, G; Degiovanni, I P; Genovese, M; Gramegna, M; Lolli, L; Monticone, E; Portesi, C; Rajteri, M; Rastello, M L; Taralli, E; Traina, P; White, M

2011-11-01

384

Beam energy absolute measurement using K-edge absorption spectrometers  

SciTech Connect

A method is presented of absolute energy measurement with an accuracy of {triangle}{Epsilon} {approximately} 10{sup {minus}4}{Epsilon}{sub o} by direct measurement of the bend angle in a high-precision magnetic dipole using two opposite-direction short (about 2 mm long) high-field-intensity magnets ({bar {Beta}} {sub dipole} {much_lt} {Beta}{sub short mag}) installed at each end and two K-edge absorption spectrometers. Using these spectrometers and the hard x-ray synchrotron radiation created by the short magnets, a bend angle of 4.5 arc deg for the CEBAF energy bandwidth can be measured with an accuracy of a few units of 10{sup {minus}6} rad, and the main sources of systematic errors are the absolute measurement of the field integral and the determination of the centroid of the synchrotron beam at a wavelength equal to the K-edge absorption of the chosen substance.

Karabekov, I.P. [Yerevan Physics Inst., Erevan (Armenia); Neil, G.R. [Continuous Electron Beam Accelerator Facility, Newport News, VA (United States)

1994-05-01

385

Absolute limit on rotation of gravitationally bound stars  

NASA Astrophysics Data System (ADS)

The authors seek an absolute limit on the rotational period for a neutron star as a function of its mass, based on the minimal constraints imposed by Einstein's theory of relativity, Le Chatelier's principle, causality, and a low-density equation of state, uncertainties which can be evaluated as to their effect on the result. This establishes a limiting curve in the mass-period plane below which no pulsar that is a neutron star can lie. For example, the minimum possible Kepler period, which is an absolute limit on rotation below which mass-shedding would occur, is 0.33 ms for a M = 1.442 solar mass neutron star (the mass of PSR1913+16). If the limit were found to be broken by any pulsar, it would signal that the confined hadronic phase of ordinary nucleons and nuclei is only metastable.

Glendenning, N. K.

1994-03-01

386

Absolute bioavailability of letrozole in healthy postmenopausal women.  

PubMed

Letrozole is a new non-steroidal inhibitor of the aromatase enzyme system. It is currently under development for the treatment of postmenopausal women with advanced breast cancer. Absolute bioavailability of letrozole when given orally as one 2.5 mg film-coated tablet in comparison to the same dose given intravenously as a bolus injection was studied in 12 healthy postmenopausal women. Letrozole absolute systemic bioavailability after p.o. administration was 99.9 +/- 16.3%. Elimination of letrozole was slow. Total-body clearance of letrozole from plasma after i.v. administration was low (2.21 L h-1). The calculated distribution volume at steady state (1.87 L kg-1) suggests a rather high tissue distribution. Biotransformation of letrozole is the main elimination mechanism with the glucuronide conjugate of the secondary alcohol metabolite being the predominant species found in urine. The two study treatments were tolerated equally well. PMID:9429742

Sioufi, A; Gauducheau, N; Pineau, V; Marfil, F; Jaouen, A; Cardot, J M; Godbillon, J; Czendlik, C; Howald, H; Pfister, C; Vreeland, F

1997-12-01

387

Absolute charge calibration of scintillating screens for relativistic electron detection  

SciTech Connect

We report on new charge calibrations and linearity tests with high-dynamic range for eight different scintillating screens typically used for the detection of relativistic electrons from laser-plasma based acceleration schemes. The absolute charge calibration was done with picosecond electron bunches at the ELBE linear accelerator in Dresden. The lower detection limit in our setup for the most sensitive scintillating screen (KODAK Biomax MS) was 10 fC/mm{sup 2}. The screens showed a linear photon-to-charge dependency over several orders of magnitude. An onset of saturation effects starting around 10-100 pC/mm{sup 2} was found for some of the screens. Additionally, a constant light source was employed as a luminosity reference to simplify the transfer of a one-time absolute calibration to different experimental setups.

Buck, A.; Popp, A.; Schmid, K.; Karsch, S.; Krausz, F. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany); Ludwig-Maximilians-Universitaet Muenchen, Am Coulombwall 1, D-85748 Garching (Germany); Zeil, K.; Jochmann, A.; Kraft, S. D.; Sauerbrey, R.; Cowan, T.; Schramm, U. [Forschungszentrum Dresden Rossendorf, Bautzner Landstrasse 400, D-01328 Dresden (Germany); Hidding, B.; Kudyakov, T. [Institut fuer Laser und Plasmaphysik, Heinrich-Heine-Universitaet Duesseldorf, Universitaetsstrasse 1, D-40225 Duesseldorf (Germany); Sears, C. M. S.; Veisz, L. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany); Pawelke, J. [Forschungszentrum Dresden Rossendorf, Bautzner Landstrasse 400, D-01328 Dresden (Germany); Oncoray, Technische Universitaet Dresden, Fetscher Strasse 74, D-01307 Dresden (Germany)

2010-03-15

388

Oblique-incidence sounder measurements with absolute propagation delay timing  

SciTech Connect

Timing from the Global Position Satellite (GPS) system has been applied to HF oblique incidence sounder measurements to produce ionograms whose propagation delay time scale is absolutely calibrated. Such a calibration is useful for interpreting ionograms in terms of the electron density true-height profile for the ionosphere responsible for the propagation. Use of the time variations in the shape of the electron density profile, in conjunction with an HF propagation model, is expected to provide better near-term (1-24 hour) HF propagation forecasts than are available from current updating systems, which use only the MUF. Such a capability may provide the basis for HF frequency management techniques which are more efficient than current methods. Absolute timing and other techniques applicable to automatic extraction of the electron-density profile from an ionogram will be discussed.

Daehler, M.

1990-05-03

389

Absolute depth estimation from a single defocused image.  

PubMed

Shape from defocus (SFD) is one of the most popular techniques in monocular 3D vision. While most SFD approaches require two or more images of the same scene captured at a fixed view point, this paper presents an efficient approach to estimate absolute depth from a single defocused image. Instead of directly measuring defocus level of each pixel, we propose to design a sequence of aperture-shape filters to segment a defocused image by defocus level. A boundary-weighted belief propagation algorithm is employed to obtain a smooth depth map. We also give an estimation of depth error. Extensive experiments show that our approach outperforms the state-of-the-art single-image SFD approaches both in precision of the estimated absolute depth and running time. PMID:23893725

Lin, Jingyu; Ji, Xiangyang; Xu, Wenli; Dai, Qionghai

2013-07-23

390

Misalignment model used in three-position absolute measurement  

NASA Astrophysics Data System (ADS)

Interferometric measurement, as dominating testing methods, is widely used in the field of optical measurement. Conventional interferometer subjects to many factors which make the measurement accuracy between ?/10 and ?/20, so it's difficult to meet the surface testing requirements of high accuracy. Thus the three-position absolute measurement technique is used to remove the errors which are introduced by reference surface and interferometer itself. The detailed process and experiment of three-position absolute measurement are given. A misalignment model by rigid body theory is presented, and the corresponding influence on interferometric measurement result is analyzed. The simulation results by the presented model are compared with that of Zemax software. By comparing both simulation results, it confirms the feasibility of the misalignment model.

Yang, Peng; Wu, Fan; Hou, Xi

2010-05-01

391

Intact absolute pitch ability after left temporal lobectomy.  

PubMed

A 17-year old pianist who possessed absolute pitch underwent an anterior left temporal lobectomy for the relief of intractable seizures. Prior to surgery he showed some fluctuation in the pattern of errors in notating single piano tones. Postoperatively he improved on this task, and one year later his performance was essentially perfect. On a short-term retention task given postoperatively he showed the expected effect of a left temporal-lobe and hippocampal lesion: he was impaired in the recall of a three-letter sequence after 18 sec with an interpolated verbal task. In contrast, retention of the names of three piano notes was excellent under the same conditions, as it is for control subjects with absolute pitch. The results are interpreted in terms of the dissociation between verbal mechanisms and those involved in the coding of pitch, and the seeming immunity of many musical abilities to the effects of left-hemisphere lesions. PMID:2612176

Zatorre, R J

1989-12-01

392

Memory for the absolute pitch of familiar songs.  

PubMed

Four experiments were conducted to examine the ability of people without "perfect pitch" to retain the absolute pitch of familiar tunes. In Experiment 1, participants imagined given tunes, and then hummed their first notes four times either between or within sessions. The variability of these productions was very low. Experiment 2 used a recognition paradigm, with results similar to those in Experiment 1 for musicians, but with some additional variability shown for unselected subjects. In Experiment 3, subjects rated the suitability of various pitches to start familiar tunes. Previously given preferred notes were rated high, as were notes three or four semitones distant from the preferred notes, but not notes one or two semitones distant. In Experiment 4, subjects mentally transformed the pitches of familiar tunes to the highest and lowest levels possible. These experiments suggest some retention of the absolute pitch of tunes despite a paucity of verbal or visual cues for the pitch. PMID:2796742

Halpern, A R

1989-09-01

393

The importance and attainment of accurate absolute radiometric calibration  

NASA Astrophysics Data System (ADS)

The importance of accurate absolute radiometric calibration is discussed by reference to the needs of those wishing to validate or use models describing the interaction of electromagnetic radiation with the atmosphere and earth surface features. The in-flight calibration methods used for the Landsat Thematic Mapper (TM) and the Systeme Probatoire d'Observation de la Terre, Haute Resolution visible (SPOT/HRV) systems are described and their limitations discussed. The questionable stability of in-flight absolute calibration methods suggests the use of a radiative transfer program to predict the apparent radiance, at the entrance pupil of the sensor, of a ground site of measured reflectance imaged through a well characterized atmosphere. The uncertainties of such a method are discussed.

Slater, P. N.

1984-01-01

394

Absolute bunch length measurements by incoherent radiation fluctuation analysis  

SciTech Connect

By analyzing the pulse to pulse intensity fluctuations of the radiation emitted by a charge particle in the incoherent part of the spectrum, it is possible to extract information about the spatial distribution of the beam. At the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory, we have developed and successfully tested a simple scheme based on this principle that allows for the absolute measurement of the rms bunch length. A description of the method and the experimental results are presented.

Sannibale, Fernando; Stupakov, Gennady; Zolotorev, Max; Filippetto, Daniele; Jagerhofer, Lukas

2008-09-29

395

Absolute Bunch Length Measurements by Incoherent Radiation Fluctuation Analysis  

SciTech Connect

By analyzing the pulse to pulse intensity fluctuations of the radiation emitted by a charge particle in the incoherent part of the spectrum, it is possible to extract information about the spatial distribution of the beam. At the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory, we have developed and successfully tested a simple scheme based on this principle that allows for the absolute measurement of the rms bunch length. A description of the method and the experimental results are presented.

Sannibale, F.; /LBL, Berkeley; Stupakov, G.V.; /SLAC; Zolotorev, M.S.; /LBL, Berkeley; Filippetto, D.; /INFN, Rome; Jagerhofer, L.; /Vienna, Tech. U.

2009-12-09

396

Least absolute value state estimation with equality and inequality constraints  

SciTech Connect

A least absolute value (LAV) state estimator, which can handle both equality and inequality constraints on measurements, is developed. It is shown that, the use of equality constraints will actually reduce the number of Simplex iterations and thus the overall cpu time. The constraints can be used to enhance the reliability of the state estimator without affecting the computational efficiency of the estimator. The developed estimation program is tested using 14 through 1,000 bus power systems.

Abur, A. (Texas A and M Univ., College Station, TX (United States)); Celik, M.K. (Pacific Gas and Electric Co., San Francisco, CA (United States))

1993-05-01

397

Secular absolute gravity trends in the northern Cascadia Subduction Zone  

Microsoft Academic Search

High-precision absolute gravity (AG) observations are sensitive to vertical motion of the observation site as well as mass redistribution within (and below) the underlying, slowly-deforming crust. The deformation gravity gradient (DGG) may be defined as the ratio of the time rate of change of surface gravity (g-dot) to vertical crustal velocity (h-dot) and provides insight into the deformation process. On

J. A. Henton; A. Lambert; N. Courtier; S. Mazzotti; H. Dragert

2009-01-01

398

Absolute Gravity Measurements in the Cascadia Subduction Zone  

Microsoft Academic Search

Monitoring of temporal gravity change at GPS sites provides an independent means of verifying inter-seismic crustal deformation associated with a locked subduction zone. High-precision gravity measurements are theoretically sensitive to both the vertical displacement of the observation site and mass redistribution in the underlying, slowly-deforming crust. FG5 absolute gravity observations have been carried out a few times per year over

A. Lambert; N. Courtier; H. Dragert; T. S. James; M. Schmidt; K. Wang; J. He

2001-01-01

399

Absolute geostrophic currents in the East Auckland Current region  

Microsoft Academic Search

Absolute geostrophic currents are estimated for the full depth of the water column off the north?east coast of New Zealand for February 1998. This is achieved by objectively?mapping subsurface Acoustic Doppler Current Profiler (ADCP) data using horizontal length scales determined from repeat high?resolution Expendable Bathythermograph (XBT) data and enforcing horizontal non?divergence. The resulting 2?dimensional map of velocity at a single

P. J. H. Sutton; T. K. Chereskin

2002-01-01

400

U.S. Geoscience Community gains an absolute gravimeter  

Microsoft Academic Search

An FG5 absolute gravimeter, which measures the gravitational acceleration of a retroreflector falling freely within an evacuated tube, is now available for use by U.S. university investigators. It will be housed as a National Science Foundation facility at NOAA's Table Mountain Gravity Observatory of the Geosciences Laboratory in Boulder, where similar units are prepared for worldwide deployment.U.S. investigators are invited

Roger Bilham; Glenn Sasagawa

1994-01-01

401

Absolute brightness temperature measurements at 3.5-mm wavelength  

Microsoft Academic Search

Careful observations have been made at 86.1 GHz to derive the absolute brightness temperatures of the sun (7914 + or - 192 K), Venus (357.5 + or - 13.1 K), Jupiter (179.4 + or - 4.7 K), and Saturn (153.4 + or - 4.8 K) with a standard error of about three percent. This is a significant improvement in accuracy

B. L. Ulich; J. H. Davis; P. J. Rhodes; J. M. Hollis

1980-01-01

402

Synthesis and absolute configuration of demethyl (C-11) cezomycin.  

PubMed

The synthesis of (-)-demethyl (C-11) cezomycin was achieved through an efficient route that features the use of a Kulinkovich reaction to couple two multifunctionality-containing fragments and a cascade of ring opening of cyclopropanol/1,5-hydrogen shift/desilylation-oxidation. The hidden yet undeniable problem of irreproducible specific rotation for this family of compounds was solved by sufficient acidification. The absolute configuration for the natural product was thus established as the mirror image of the synthetic sample. PMID:23881716

Li, Shao-Gang; Wu, Yikang

2013-07-23

403

Absolute calibration of imaging plate for GeV electrons  

SciTech Connect

An imaging plate has been used as a useful detector of energetic electrons in laser electron acceleration and laser fusion studies. The absolute sensitivity of an imaging plate was calibrated at 1 GeV electron energy using the injector Linac of SPring-8. The sensitivity curve obtained up to 100 MeV in a previous study was extended successfully to GeV range.

Nakanii, N.; Kondo, K.; Yabuuchi, T.; Tsuji, K.; Tanaka, K. A. [Graduate School of Engineering, Osaka University, 2-1, Yamada-oka, Suita, Osaka 565-0871, Japan, and Institute of Laser Engineering, Osaka University, 2-6, Yamada-oka, Suita, Osaka 565-0871 (Japan); Suzuki, S.; Asaka, T.; Yanagida, K.; Hanaki, H. [Japan Synchrotron Radiation Research Institute/SPring-8, 1-1, Koto 1-chome, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Kobayashi, T.; Makino, K.; Yamane, T. [FUJIFILM Corporation, 798, Miyanodai, Ashigarakami, Kanagawa 258-8538, Japan and FUJIFILM Corporation, 26-30, Nishiazabu 2-chome, Minato-ku, Tokyo 106-8620 (Japan); Miyamoto, S.; Horikawa, K. [Laboratory of Advanced Science and Technology for Industry, University of Hyogo, 1-2, Koto 3-chome, Kamigori-cho, Ako-gun, Hyogo 678-1205 (Japan)

2008-06-15

404

Absolute calibration of imaging plate for GeV electrons.  

PubMed

An imaging plate has been used as a useful detector of energetic electrons in laser electron acceleration and laser fusion studies. The absolute sensitivity of an imaging plate was calibrated at 1 GeV electron energy using the injector Linac of SPring-8. The sensitivity curve obtained up to 100 MeV in a previous study was extended successfully to GeV range. PMID:18601438

Nakanii, N; Kondo, K; Yabuuchi, T; Tsuji, K; Tanaka, K A; Suzuki, S; Asaka, T; Yanagida, K; Hanaki, H; Kobayashi, T; Makino, K; Yamane, T; Miyamoto, S; Horikawa, K

2008-06-01

405

Absolute and relative choreographies in rigid body dynamics  

Microsoft Academic Search

For the classical problem of motion of a rigid body about a fixed point with zero area integral, we present a family of solutions\\u000a that are periodic in the absolute space. Such solutions are known as choreographies. The family includes the well-known Delone\\u000a solutions (for the Kovalevskaya case), some particular solutions for the Goryachev-Chaplygin case, and the Steklov solution.\\u000a The

A. V. Borisov; A. A. Kilin; I. S. Mamaev

2008-01-01

406

Absolute age of volcanogenic formations of the central Siberian Platform  

Microsoft Academic Search

An absolute-age determination of the tuffs, volcanic bombs, re-explosive fragments, lava flows, and extrusive rocks of the Korvunchana series of the central part of the Siberian Platform indicates that most of the volcanics appear to be older (P1-P2) than that assumed up to now (T1). Among the determinations, Late Permian dates predominate. Two determinations gave figures of 190 and 172

V. A. Naumov; A. M. Mukhina

1977-01-01

407

Quantaurus-QY: Absolute photoluminescence quantum yield spectrometer  

NASA Astrophysics Data System (ADS)

Quantaurus-QY was developed as a compact, easy-to-use system with a small footprint based on Hamamatsu's established C9920-02/03 systems for measuring absolute photoluminescence quantum yields. Operating this system is simple: load a sample and press the start button to measure the photoluminescence quantum yields, excitation wavelength dependence, photoluminescence excitation spectrum and other properties in a short period of time.

Suzuki, Kengo

2011-05-01

408

Automated absolute activation analysis with californium-252 sources  

Microsoft Academic Search

A 100-mg ²⁵²Cf neutron activation analysis facility is used routinely at the Savannah River Laboratory for multielement analysis of many solid and liquid samples. An absolute analysis technique converts counting data directly to elemental concentration without the use of classical comparative standards and flux monitors. With the totally automated pneumatic sample transfer system, cyclic irradiation-decay-count regimes can be pre-selected for

K. W. MacMurdo; W. W. Bowman

1978-01-01

409

Absolute spectrophotometry of 22 vulpeculae during the eclipse of 1990  

NASA Astrophysics Data System (ADS)

The results of broadband photometric observations of 22 Vulpeculae (QS Vulpeculae) between 1984 and 1994 have been considered and unified to produce a composite light curve. The spectral types of the binary components and their contributions to the total luminosity of the binary are estimated using the absolute spectrophotometry of 22 Vulpeculae. The absorption in the visible region is taken to be A( V) = 0 m .0.

Burnashev, V. I.; Burnasheva, B. A.

2013-06-01

410

Diagnostic Application of Absolute Neutron Activation Analysis in Hematology  

SciTech Connect

The Absolute Neutron Activation Analysis (ANAA) technique was used to determine element concentrations of Cl and Na in blood of healthy group (male and female blood donators), select from Blood Banks at Sao Paulo city, to provide information which can help in diagnosis of patients. This study permitted to perform a discussion about the advantages and limitations of using this nuclear methodology in hematological examinations.

Zamboni, C.B.; Oliveira, L.C.; Dalaqua, L. Jr.

2004-10-03

411

Absolute partial decay branching-ratios in 16O  

NASA Astrophysics Data System (ADS)

The a-transfer reaction 126C(63Li, d)168O* has been performed at a 6Li bombarding energy of 42 MeV to populate excited states in 13C and 16O. Absolute branching ratios have been unambiguously determined for states in the excitation energy range 13.85 to 15.87 MeV and reduced widths are extracted.

Wheldon, C.; Ashwood, N. I.; Barr, M.; Curtis, N.; Freer, M.; Kokalova, Tz; Malcolm, J. D.; Spencer, S. J.; Ziman, V. A.; Faestermann, Th; Krcken, R.; Wirth, H.-F.; Hertenberger, R.; Lutter, R.; Bergmaier, A.

2013-04-01

412

THE ABSOLUTE MAGNITUDES OF TYPE Ia SUPERNOVAE IN THE ULTRAVIOLET  

SciTech Connect

We examine the absolute magnitudes and light-curve shapes of 14 nearby (redshift z = 0.004-0.027) Type Ia supernovae (SNe Ia) observed in the ultraviolet (UV) with the Swift Ultraviolet/Optical Telescope. Colors and absolute magnitudes are calculated using both a standard Milky Way extinction law and one for the Large Magellanic Cloud that has been modified by circumstellar scattering. We find very different behavior in the near-UV filters (uvw1{sub rc} covering {approx}2600-3300 A after removing optical light, and u {approx} 3000-4000 A) compared to a mid-UV filter (uvm2 {approx}2000-2400 A). The uvw1{sub rc} - b colors show a scatter of {approx}0.3 mag while uvm2-b scatters by nearly 0.9 mag. Similarly, while the scatter in colors between neighboring filters is small in the optical and somewhat larger in the near-UV, the large scatter in the uvm2 - uvw1 colors implies significantly larger spectral variability below 2600 A. We find that in the near-UV the absolute magnitudes at peak brightness of normal SNe Ia in our sample are correlated with the optical decay rate with a scatter of 0.4 mag, comparable to that found for the optical in our sample. However, in the mid-UV the scatter is larger, {approx}1 mag, possibly indicating differences in metallicity. We find no strong correlation between either the UV light-curve shapes or the UV colors and the UV absolute magnitudes. With larger samples, the UV luminosity might be useful as an additional constraint to help determine distance, extinction, and metallicity in order to improve the utility of SNe Ia as standardized candles.

Brown, Peter J.; Roming, Peter W. A.; Ciardullo, Robin; Gronwall, Caryl; Hoversten, Erik A.; Pritchard, Tyler [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Milne, Peter [Steward Observatory, University of Arizona, Tucson, AZ 85719 (United States); Bufano, Filomena; Mazzali, Paolo [INAF-Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, I-35122 Padova (Italy); Elias-Rosa, Nancy [Spitzer Science Center, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Filippenko, Alexei V.; Li Weidong [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Foley, Ryan J.; Hicken, Malcolm; Kirshner, Robert P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Gehrels, Neil; Holland, Stephen T.; Immler, Stefan [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Phillips, Mark M. [Las Campanas Observatory, Casilla 601, La Serena (Chile); Still, Martin, E-mail: pbrown@physics.utah.ed [Mullard Space Science Laboratory, Department of Space and Climate Physics, University College London, Holmbury St. Mary, Dorking, Surrey, RH5 6NT (United Kingdom)

2010-10-01

413

Spatially resolved absolute spectrophotometry of Saturn - 3390 to 8080 A  

Microsoft Academic Search

A series of spatially resolved absolute spectrophotometric measurements of Saturn was conducted for the expressed purpose of calibrating the data obtained with the Imaging Photopolarimeter (IPP) on Pioneer 11 during its recent encounter with Saturn. All observations reported were made at the Mt. Wilson 1.5-m telescope, using a 1-m Ebert-Fastie scanning spectrometer. Spatial resolution was 1.92 arcsec. Photometric errors are

J. T. Bergstralh; G. S. Orton; D. J. Diner; K. H. Baines; J. S. Neff; M. A. Allen

1981-01-01

414

Absolute ionisation functions for electron impact with barium  

Microsoft Academic Search

Absolute ionisation functions sigma n+(E)(n=1,2,3,4) and the total ionisation function sigma tot(E) for electron impact with barium have been determined for energies up to 600 eV. Modified crossed-beam techniques were applied using the excitation function of the light from the resonance transition as a reference standard for the cross sections. A time-of-flight device was used to separate ions with different

J.-M. Dettmann; F. Karstensen

1982-01-01

415

Absolute-gravity stations in Western Dronning Maud Land, Antarctica  

NASA Astrophysics Data System (ADS)

Absolute-gravity stations are an important part of the geodetic infrastructure of the Antarctic. They provide accurate starting values for gravity surveys performed e.g. for the determination of the geoid, for geological studies and for geophysical investigations. The time variation in gravity determined from repeated absolute-gravity measurements provides insights into the Glacial Isostatic Adjustment (GIA) and into solid Earth deformation due to variation in contemporary ice load. Given sufficient joint coverage with International Terrestrial Reference Frame (ITRF) sites, gravity rates in high latitudes could in principle provide an independent check of the geocentricity of the z-dot (velocities in the direction of the rotation axis of the Earth) of the ITRF. We review the absolute gravity stations in Western and Central Dronning Maud Land. The oldest station is at the Finnish base Aboa, with 5 measurements by the Finnish Geodetic Institute (FGI) starting with the FINNARP 1993 expedition. Measurements at Maitri (India) and Novolazarevskaya (Russia) were first performed in 2004 by the National Geophysical Research Institute (NGRI) of India, and by the FGI, respectively. In the season 2010/11 a new station was constructed at Troll (Norway). In the season 2011/12 the aforementioned four sites were occupied by the FG5-221 absolute gravimeter of the FGI. At Sanae IV (South Africa) there are previous occupations by the FG5-221, in 2003/4 and 2005/6. All these bases have continuous GNSS stations. Numerous supporting measurements have been made at the sites: microgravity networks, levelling and GNSS ties to excentres etc., for controlling the stability of the stations. At some sites, nearby glacier elevations were surveyed to monitor the attraction of the variable close-field snow and ice masses. We give a description of the sites and the measurements performed at them. The work has benefited from the co-operation in the COST Action ES0701 "Improved Constraints on Models of GIA".

Mkinen, Jaakko; Rasindra, Ravik; Chand, Uttam; Tiwari, Virendra; Lukin, Valery; Anisimov, Michail; Melvaer, Yngve; Melland, Gudmund; Koivula, Hannu; Nrnen, Jyri; Poutanen, Markku

2013-04-01

416

Absolute GNSS Antenna Calibration at the National Geodetic Survey  

NASA Astrophysics Data System (ADS)

Geodetic GNSS applications routinely demand millimeter precision and extremely high levels of accuracy. To achieve these accuracies, measurement and instrument biases at the centimeter to millimeter level must be understood. One of these biases is the antenna phase center, the apparent point of signal reception for a GNSS antenna. It has been well established that phase center patterns differ between antenna models and manufacturers; additional research suggests that the addition of a radome or the choice of antenna mount can significantly alter those a priori phase center patterns. For the more demanding GNSS positioning applications and especially in cases of mixed-antenna networks, it is all the more important to know antenna phase center variations as a function of both elevation and azimuth in the antenna reference frame and incorporate these models into analysis software. To help meet the needs of the high-precision GNSS community, the National Geodetic Survey (NGS) now operates an absolute antenna calibration facility. Located in Corbin, Virginia, this facility uses field measurements and actual GNSS satellite signals to quantitatively determine the carrier phase advance/delay introduced by the antenna element. The NGS facility was built to serve traditional NGS constituents such as the surveying and geodesy communities, however calibration services are open and available to all GNSS users as the calibration schedule permits. All phase center patterns computed by this facility will be publicly available and disseminated in both the ANTEX and NGS formats. We describe the NGS calibration facility, and discuss the observation models and strategy currently used to generate NGS absolute calibrations. We demonstrate that NGS absolute phase center variation (PCV) patterns are consistent with published values determined by other absolute antenna calibration facilities, and outline future planned refinements to the system.

Mader, G.; Bilich, A.; Geoghegan, C.

2012-04-01

417

Global relative and absolute quantitation in microbial proteomics.  

PubMed

Proteomic studies are designed to yield either qualitative information on proteins (identification, distribution, posttranslational modifications, interactions, structure and function) or quantitative information (abundance, distribution within different localizations, temporal changes in abundance due to synthesis and degradation or both). To this end these studies can draw upon a wide range of qualitative and quantitative gel-based and gel-free techniques. This review summarizes current proteomic workflows for global relative or absolute protein quantitation and their application in microbial physiology. PMID:22445110

Otto, Andreas; Bernhardt, Jrg; Hecker, Michael; Becher, Drte

2012-03-21

418

Stack filters and the mean absolute error criterion  

Microsoft Academic Search

A method to determine the stack filter which minimizes the mean absolute error between its output and a desired signal, given noisy observations of this desired signal, is presented. Specifically, an optimal window-width-b stack filter can be determined with a linear program with O(b2b) variables. This algorithm is efficient since the number of different inputs to a window-width-b filter is

E. J. Coyle; J.-H. Lin

1988-01-01

419

Infrared nondestructive measurement of thermal resistance between liner and engine block: design of experiment  

Microsoft Academic Search

Thermal resistances between liners and engine blocks are nondestructively studied by photothermal infrared thermography. Under controlled sinusoidal light irradiation, the thermal response of the sample is measured by means of an infrared camera. A numerical lock-in procedure yields amplitude and absolute phase maps of the thermal field periodic component. Then, apart from classical qualitative detection of air layers, a quantitative

P. Laloue; C. Bissieux; J.-F. Henry; H. Pron; J. L'Ecolier; F. Nigon

2008-01-01

420

Two-state irreversible thermal denaturation of Euphorbia characias latex amine oxidase  

Microsoft Academic Search

Thermal denaturation of Euphorbia latex amine oxidase (ELAO) has been studied by enzymatic activity, circular dichroism and differential scanning calorimetry. Thermal denaturation of ELAO is shown to be an irreversible process. Checking the validity of two-state it really describes satisfactorily the thermal denaturation of ELAO. Based on this model we obtain the activation energy, parameter T? (the absolute temperature at

Mojtaba Amani; Ali A. Moosavi-Movahedi; Giovanni Floris; Anna Mura; Boris I. Kurganov; Faizan Ahmad; Ali A. Saboury

2007-01-01

421

Rapid and precise absolute distance measurements at long range  

NASA Astrophysics Data System (ADS)

The ability to determine absolute distance to an object is one of the most basic measurements of remote sensing. High-precision ranging has important applications in both large-scale manufacturing and in future tight formation-flying satellite missions, where rapid and precise measurements of absolute distance are critical for maintaining the relative pointing and position of the individual satellites. Using two coherent broadband fibre-laser frequency comb sources, we demonstrate a coherent laser ranging system that combines the advantages of time-of-flight and interferometric approaches to provide absolute distance measurements, simultaneously from multiple reflectors, and at low power. The pulse time-of-flight yields a precision of 3 m with an ambiguity range of 1.5 m in 200 s. Through the optical carrier phase, the precision is improved to better than 5 nm at 60 ms, and through the radio-frequency phase the ambiguity range is extended to 30 km, potentially providing 2 parts in 1013 ranging at long distances.

Coddington, I.; Swann, W. C.; Nenadovic, L.; Newbury, N. R.

2009-06-01

422

Absolutely minimal extensions of functions on metric spaces  

SciTech Connect

Extensions of a real-valued function from the boundary {partial_derivative}X{sub 0} of an open subset X{sub 0} of a metric space (X,d) to X{sub 0} are discussed. For the broad class of initial data coming under discussion (linearly bounded functions) locally Lipschitz extensions to X{sub 0} that preserve localized moduli of continuity are constructed. In the set of these extensions an absolutely minimal extension is selected, which was considered before by Aronsson for Lipschitz initial functions in the case X{sub 0} subset of R{sup n}. An absolutely minimal extension can be regarded as an {infinity}-harmonic function, that is, a limit of p-harmonic functions as p{yields}+{infinity}. The proof of the existence of absolutely minimal extensions in a metric space with intrinsic metric is carried out by the Perron method. To this end, {infinity}-subharmonic, {infinity}-superharmonic, and {infinity}-harmonic functions on a metric space are defined and their properties are established.

Milman, V A [Institute of Technical Cybernetics, National Academy of Sciences of Belarus (Belarus)

1999-06-30

423

Peripheral absolute threshold spectral sensitivity in retinitis pigmentosa.  

PubMed Central

Dark-adapted spectral sensitivities were measured in the peripheral retinas of 38 patients diagnosed as having typical retinitis pigmentosa (RP) and in 3 normal volunteers. The patients included those having autosomal dominant and autosomal recessive inheritance patterns. Results were analysed by comparisons with the CIE standard scotopic spectral visibility function and with Judd's modification of the photopic spectral visibility function, with consideration of contributions from changes in spectral transmission of preretinal media. The data show 3 general patterns. One group of patients had absolute threshold spectral sensitivities that were fit by Judd's photopic visibility curve. Absolute threshold spectral sensitivities for a second group of patients were fit by a normal scotopic spectral visibility curve. The third group of patients had absolute threshold spectral sensitivities that were fit by a combination of scotopic and photopic spectral visibility curves. The autosomal dominant and autosomal recessive modes of inheritance were represented in each group of patients. These data indicate that RP patients have normal rod and/or cone spectral sensitivities, and support the subclassification of patients described previously by Massof and Finkelstein.

Massof, R W; Johnson, M A; Finkelstein, D

1981-01-01

424

Investigating the absolute phase information in acoustic wave resonance scattering.  

PubMed

The aim of this work is to investigate the absolute phase information in resonance acoustic scattering by spheres and cylinders and place this work in the broader context of scattering in which the properties of the magnitude and (processed) phase have been examined in a more general way than in the classical resonance scattering theory (RST). Here, comparisons are made between the classical and modified RST formalisms of acoustic resonance scattering. Experimental and theoretical backscattering form functions are obtained and discussed. It is shown that the magnitude and processed (unwrapped) phase can be correctly obtained through the classical RST, suggesting that the modified RST formalism offers little new practical advantage. Furthermore, the absolute phase is shown to be very sensitive to object's resonances, suggesting that the unwrapped phase may be considered as an efficient tool, along with the magnitude information, to carry out remote (active) classification of targets in underwater acoustics applications. The combination of absolute phase information with the magnitude data offers a complementary advantage in the identification of resonances from cylinders and spheres. PMID:18294670

Mitri, F G; Greenleaf, J F; Fellah, Z E A; Fatemi, M

2008-01-18

425

Absolute cross sections for electron scattering from furan  

NASA Astrophysics Data System (ADS)

We report results of measurements and calculations of absolute cross sections for electron scattering from furan molecules (C4H4O). The experimental absolute differential cross sections (DCSs) for elastic electron scattering were obtained for the incident energies from 50 eV to 300 eV and for scattering angles from 20 to 110, by using a crossed electron-target beam setup and the relative flow technique for calibration to the absolute scale. The calculations of the electron interaction cross sections are based on a corrected form of the independent-atom method, known as the screening corrected additivity rule (SCAR) procedure and using an improved quasifree absorption model. The latter calculations also account for rotational excitations in the approximation of a free electric dipole and were used to obtain elastic DCSs as well as total and integral elastic cross sections which are tabulated in the energy range from 10 to 10 000 eV. All SCAR calculated cross sections agree very well with both the present and previously published experimental results. Additionally, calculations based on the first Born approximation were performed to calculate both elastic and vibrationally inelastic DCSs for all the modes of furane, in the energy range from 50 eV to 300 eV. The ratios of the summed vibrational to elastic DCSs are presented and discussed. Finally, the present results for furan are compared with previously published elastic DCSs for the tetrahydrofuran molecule and discussed.

Maljkovi?, J. B.; Blanco, F.; ?urk, R.; Garca, G.; Marinkovi?, B. P.; Milosavljevi?, A. R.

2012-08-01

426

Measurement of absolute optical thickness by wavelength tuning interferometer  

NASA Astrophysics Data System (ADS)

Absolute optical thickness is a fundamental parameter for the design of optical elements. In semiconductor industry, it is necessary to measure the absolute optical thickness of the central part of the projection lenses with a high accuracy. However, even when the geometrical thickness is perfectly known, a typical refractive index of fused-silica has an ambiguity of 6 10-5 that gives an uncertainty of 180 nm in the optical thickness for a 3 mm-thick plate. Moreover, the optical thickness measured by white light interferometry and wavelength tuning interferometry is an optical thickness with respect to not the ordinary refractive index but the group refractive index. We measured the ordinary optical thickness of a fused silica plate of 6-inch square and 3 mm thickness by a wavelength tuning interferometer with a tunable phase shifting technique. We assumed the typical refractive index and dispersion of the fused silica as approximate values. The absolute interference order for the optical thickness was finally estimated, which gives a measurement resolution of typically 10 nm for the optical thickness.

Hibino, Kenichi; Kim, Yangjin; Bitou, Youichi; Mitsuishi, Mamoru

2011-08-01

427

Thermal quenching of the fluorescence quantum efficiency in colquiriite crystals measured by thermal lens spectrometry  

Microsoft Academic Search

The dual-beam mode-mismatched thermal lens technique was used to study the temperature dependence of the absolute fluorescence quantum efficiency (?) of a thermal-quenching fluorescence (TQF) process in Cr3+-doped colquiriite crystals (LiSAF and LiSGaF), from 300 to 450 K. The research was developed at a low excitation-power level in order to eliminate the energy-transfer upconversion effect. The results showed that TQF

Viviane Pilla; Tomaz Catunda; Sandro Marcio Lima; Antonio Neto Medina; Mauro Luciano Baesso; Hans P. Jenssen; Arlete Cassanho

2004-01-01

428

Can Portable Technology Capture Subtle Phenomena, Related to Quakes, Hurricanes, Tornados, and Volcanoes, Culturally Reported in the Americas by an Equivalent of ``Kokopelli'' or ari Huallac, i.e., the EMF?  

NASA Astrophysics Data System (ADS)

Peruvians who produced the CD ARI HUALAC say this name of their home village represents two of their few original words, meaning ``serpent God.'' Arizona, hurricane, mullah, Molocket, Millinocket and Allagash of Maine, Allahpata, and Apalachicola of FL, and Allegheny of PA are some partial cognates for these ancient words. They are culturally detected aspects of the EMF, like Kokopelli, the ``hunchbacked, flute-playing, dancing around'' icon of our southwest. That aspect of `flutes' indicated by tinnitus, and its co-associated symptoms of Meuniere's syndrome, along with the sensation of `pins and needles', signify the rotation of secondary magnetic poles, stimulating nerve endings with their EMF that technology can detect, here and in Brazil. Can they fool us about some religious concepts?

Ataide, Jade; McLeod, Roger

2006-03-01

429

Extremely low-frequency electromagnetic field (ELF-EMF) does not affect the expression of ?3, ?5 and ?7 nicotinic receptor subunit genes in SH-SY5Y neuroblastoma cell line  

Microsoft Academic Search

Neuronal nicotinic acetylcholine receptors (nAChRs) are involved in a number of functional processes, including cognition, learning and memory, and alterations in their expression and\\/or activity have been implicated in various neurological disorders such as Alzheimer's disease (AD), Parkinson's disease and schizophrenia. Epidemiological studies have shown that exposure to electromagnetic fields (EMF) may contribute to the pathogenesis of neurodegenerative diseases such

Ruth Adele Antonini; Roberta Benfante; Cecilia Gotti; Milena Moretti; Niels Kuster; Juergen Schuderer; Francesco Clementi; Diego Fornasari

2006-01-01

430

Autoimmune processes after long-term low-level exposure to electromagnetic fields (experimental results) part 3. The effect of long-term nonthermal RF EMF exposure on complement-fixation antibodies against homologenous tissue  

Microsoft Academic Search

The effect of long-term nonthermal EMF exposure of 2450 MHz (500 ?W\\/cm2) on the level of antibodies against brain and liver tissues is studied on rats by the complement-fixation test (CFT) in the\\u000a cold. It is found that a statistically significant increase in the level of antibodies against aqueous extracts of brain and\\u000a liver tissues in blood serum is detected

A. A. Ivanov; Y. G. Grigoriev; V. N. Maltsev; A. M. Ulanova; N. M. Stavrakova; V. G. Skachkova; O. A. Grigoriev

2010-01-01

431

Changes in neurite outgrowth but not in cell division induced by low EMF exposure: influence of field strength and culture conditions on responses in rat PC12 pheochromocytoma cells  

Microsoft Academic Search

The effects of low electromagnetic field (EMF) exposure (4.515.8 ?T, 50 Hz AC) on neurite outgrowth and cell division in rat PC12 pheochromocytoma cells were examined. The study involved two separate experimental series in which culture conditions during exposure to the magnetic fields differed. In series 1 (14 experiments in which culture conditions were not strongly conducive to cell differentiation

Elizabeth H McFarlane; Gavin S Dawe; Maureen Marks; Iain C Campbell

2000-01-01

432

Thermo-emf of the phases of the semiconductor eutectic alloys of the systems A/sup III/B/sup V/-Ge(Si) and Te-A/sub 2//sup V/Te/sub 3/  

SciTech Connect

In this work we determined the sign and magnitude of the thermo-emf of the phase of two-phase eutectic ingots Te + Bi/sub 2/Te/sub 3/ and Te + Sb/sub 2/Te/sub 3/. We measured the thermo-emf for ingots of eutectic composition for the systems GaAs-Si, InAs-Ge, GaAs-Ge, GaSb-Ge, InSb-Ge, In/sub x/Ga/sub 1-x/Sb-Ge, In/sub x/Ga/sub 1-x/As-Ge at points along the same line and separated from one another by 5 ..mu..m. The smallest spacing of the inclusions equaled about 10 ..mu..m. It was established based on measurements of the thermo-emf that alloys with the eutectic composition of the systems A/sup III/B/sup V/-Ge(Si) and Te-A/sub 2//sup V/Te/sub 3/ are formed by two solid solution, in which the electric charge density must be taken into account. The type of conductivity of the phases and of the entire alloy in most cases is determined by the conductivity of the matrix phase.

Gantimurova, Z.K.; Leonov, V.V.; Chunarev, E.N.; Chuyashov, K.I.

1988-02-01

433

Improved Strategies and Optimization of Calibration Models for Real-time PCR Absolute Quantification  

EPA Science Inventory

Real-time PCR absolute quantification applications rely on the use of standard curves to make estimates of DNA target concentrations in unknown samples. Traditional absolute quantification approaches dictate that a standard curve must accompany each experimental run. However, t...

434

Bandwidth-Substitution Technique for Absolute Measurement of Power at All Radio Frequencies.  

National Technical Information Service (NTIS)

A highly sensitive technique for making absolute measurements of power at all radio frequencies is described. This technique surmounts the primary shortcomings of the other existing techniques in that it permits absolute measurement of power at all radio ...

A. Singer J. M. Minkowski

1976-01-01

435

Absolute quantification of cell-bound DNA aptamers during SELEX.  

PubMed

In the fields of diagnosis, imaging, regenerative medicine, and drug targeting, aptamers are promising nucleic acid ligands for specific recognition and binding of whole living cells. These aptamers are selected by a combinatorial chemistry technique called cell-SELEX (Systematic Evolution of Ligands by EXponential enrichment). During this iterative procedure of in vitro selection and enzymatic amplification, the enrichment of cell binding aptamers is generally monitored by flow cytometry. This method needs the use of fluorophore-labeled oligonucleotides for detection and allows only the relative evaluation of the aptamer binding compared with the control. Here, we describe the development and validation of a new quantitative real time polymerase chain reaction (qPCR) method for the absolute determination of cell bound aptamers during cell-SELEX. The method is based on SYBR Green I real-time PCR technology and uses an aptamer standard curve to determine the accurate aptamer amount on cells after the incubations. Lysates of cells with bound aptamers were used to identify the absolute amount of aptamers on cells. This method is highly sensitive and allows the detection of very small quantities of aptamers in cell lysate samples. The lower detection limit is 20 fg. The established qPCR method can be used as an additional monitoring tool during cell-SELEX to determine the enrichment of cell binding aptamers on cells, whereby the absolute quantity is determined. Furthermore, the contamination of the amplified aptamer pool with by-products can be prevented by prior determination of bound aptamer amount on cells. PMID:23405949

Avci-Adali, Meltem; Wilhelm, Nadja; Perle, Nadja; Stoll, Heidi; Schlensak, Christian; Wendel, Hans P

2013-02-13

436

Subcortical neural synchrony and absolute thresholds predict frequency discrimination independently.  

PubMed

The neural mechanisms of pitch coding have been debated for more than a century. The two main mechanisms are coding based on the profiles of neural firing rates across auditory nerve fibers with different characteristic frequencies (place-rate coding), and coding based on the phase-locked temporal pattern of neural firing (temporal coding). Phase locking precision can be partly assessed by recording the frequency-following response (FFR), a scalp-recorded electrophysiological response that reflects synchronous activity in subcortical neurons. Although features of the FFR have been widely used as indices of pitch coding acuity, only a handful of studies have directly investigated the relation between the FFR and behavioral pitch judgments. Furthermore, the contribution of degraded neural synchrony (as indexed by the FFR) to the pitch perception impairments of older listeners and those with hearing loss is not well known. Here, the relation between the FFR and pure-tone frequency discrimination was investigated in listeners with a wide range of ages and absolute thresholds, to assess the respective contributions of subcortical neural synchrony and other age-related and hearing loss-related mechanisms to frequency discrimination performance. FFR measures of neural synchrony and absolute thresholds independently contributed to frequency discrimination performance. Age alone, i.e., once the effect of subcortical neural synchrony measures or absolute thresholds had been partialed out, did not contribute to frequency discrimination. Overall, the results suggest that frequency discrimination of pure tones may depend both on phase locking precision and on separate mechanisms affected in hearing loss. PMID:23760984

Marmel, F; Linley, D; Carlyon, R P; Gockel, H E; Hopkins, K; Plack, C J

2013-06-13

437

Absolute dose calculations for Monte Carlo simulations of radiotherapy beams  

NASA Astrophysics Data System (ADS)

Monte Carlo (MC) simulations have traditionally been used for single field relative comparisons with experimental data or commercial treatment planning systems (TPS). However, clinical treatment plans commonly involve more than one field. Since the contribution of each field must be accurately quantified, multiple field MC simulations are only possible by employing absolute dosimetry. Therefore, we have developed a rigorous calibration method that allows the incorporation of monitor units (MU) in MC simulations. This absolute dosimetry formalism can be easily implemented by any BEAMnrc/DOSXYZnrc user, and applies to any configuration of open and blocked fields, including intensity-modulated radiation therapy (IMRT) plans. Our approach involves the relationship between the dose scored in the monitor ionization chamber of a radiotherapy linear accelerator (linac), the number of initial particles incident on the target, and the field size. We found that for a 10 10 cm2 field of a 6 MV photon beam, 1 MU corresponds, in our model, to 8.129 1013 1.0% electrons incident on the target and a total dose of 20.87 cGy 1.0% in the monitor chambers of the virtual linac. We present an extensive experimental verification of our MC results for open and intensity-modulated fields, including a dynamic 7-field IMRT plan simulated on the CT data sets of a cylindrical phantom and of a Rando anthropomorphic phantom, which were validated by measurements using ionization chambers and thermoluminescent dosimeters (TLD). Our simulation results are in excellent agreement with experiment, with percentage differences of less than 2%, in general, demonstrating the accuracy of our Monte Carlo absolute dose calculations.

Popescu, I. A.; Shaw, C. P.; Zavgorodni, S. F.; Beckham, W. A.

2005-07-01

438

Control of absolute negative mobility via noise recycling procedure  

NASA Astrophysics Data System (ADS)

Absolute negative mobility (ANM) is investigated in a spatially-periodic symmetric system under the influence of noise consisting of the superposition of a white Gaussian noise with the same noise delayed by time ?. The effects of the noise intensity ?, the time delay ? and feedback intensity ? in the noise recycling are discussed. It is found that the noise intensity ? and time delay ? can induce the phenomenon of ANM, while the feedback intensity ? can not induce it. This phenomenon of ANM can be tested in the setup consisting of a resistively and capacitively shunted Josephson junction device by using a vertical cavity surface emitting laser to generate the noise recycling procedure.

Zeng, C. H.; Wang, H.; Qing, S.; Hu, J. H.; Li, K. Z.

2012-10-01

439

Measurement of the Absolute Branching Fraction of D0?K-?+  

NASA Astrophysics Data System (ADS)

We measure the absolute branching fraction for D0?K-?+ using partial reconstruction of B0?D*+X?-?? decays, in which only the charged lepton and the pion from the decay D*+?D0?+ are used. Based on a data sample of 230106 BB pairs collected at the ?(4S) resonance with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC, we obtain B(D0?K-?+)=(4.0070.0370.072)%, where the first uncertainty is statistical and the second is systematic.

Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Eigen, G.; Ofte, I.; Stugu, B.; Sun, L.; Abrams, G. S.; Battaglia, M.; Brown, D. N.; Button-Shafer, J.; Cahn, R. N.; Groysman, Y.; Jacobsen, R. G.; Kadyk, J. A.; Kerth, L. T.; Kolomensky, Yu. G.; Kukartsev, G.; Lopes Pegna, D.; Lynch, G.; Mir, L. M.; Orimoto, T. J.; Pripstein, M.; Roe, N. A.; Ronan, M. T.; Tackmann, K.; Wenzel, W. A.; Del Amo Sanchez, P.; Hawkes, C. M.; Watson, A. T.; Held, T.; Koch, H.; Lewandowski, B.; Pelizaeus, M.; Schroeder, T.; Steinke, M.; Cottingham, W. N.; Walker, D.; Asgeirsson, D. J.; Cuhadar-Donszelmann, T.; Fulsom, B. G.; Hearty, C.; Knecht, N. S.; Mattison, T. S.; McKenna, J. A.; Khan, A.; Saleem, M.; Teodorescu, L.; Blinov, V. E.; Bukin, A. D.; Druzhinin, V. P.; Golubev, V. B.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu; Bondioli, M.; Curry, S.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Lund, P.; Mandelkern, M.; Martin, E. C.; Stoker, D. P.; Abachi, S.; Buchanan, C.; Foulkes, S. D.; Gary, J. W.; Liu, F.; Long, O.; Shen, B. C.; Zhang, L.; Paar, H. P.; Rahatlou, S.; Sharma, V.; Berryhill, J. W.; Campagnari, C.; Cunha, A.; Dahmes, B.; Hong, T. M.; Kovalskyi, D.; Richman, J. D.; Beck, T. W.; Eisner, A. M.; Flacco, C. J.; Heusch, C. A.; Kroseberg, J.; Lockman, W. S.; Schalk, T.; Schumm, B. A.; Seiden, A.; Williams, D. C.; Wilson, M. G.; Winstrom, L. O.; Chen, E.; Cheng, C. H.; Dvoretskii, A.; Fang, F.; Hitlin, D. G.; Narsky, I.; Piatenko, T.; Porter, F. C.; Mancinelli, G.; Meadows, B. T.; Mishra, K.; Sokoloff, M. D.; Blanc, F.; Bloom, P. C.; Chen, S.; Ford, W. T.; Hirschauer, J. F.; Kreisel, A.; Nagel, M.; Nauenberg, U.; Olivas, A.; Smith, J. G.; Ulmer, K. A.; Wagner, S. R.; Zhang, J.; Gabareen, A. M.; Soffer, A.; Toki, W. H.; Wilson, R. J.; Winklmeier, F.; Zeng, Q.; Altenburg, D. D.; Feltresi, E.; Hauke, A.; Jasper, H.; Merkel, J.; Petzold, A.; Spaan, B.; Wacker, K.; Brandt, T.; Klose, V.; Lacker, H. M.; Mader, W. F.; Nogowski, R.; Schubert, J.; Schubert, K. R.; Schwierz, R.; Sundermann, J. E.; Volk, A.; Bernard, D.; Bonneaud, G. R.; Latour, E.; Lombardo, V.; Thiebaux, Ch.; Verderi, M.; Clark, P. J.; Gradl, W.; Muheim, F.; Playfer, S.; Robertson, A. I.; Xie, Y.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cecchi, A.; Cibinetto, G.; Franchini, P.; Luppi, E.; Negrini, M.; Petrella, A.; Piemontese, L.; Prencipe, E.; Santoro, V.; Anulli, F.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Pacetti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Buzzo, A.; Contri, R.; Lo Vetere, M.; Macri, M. M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Santroni, A.; Tosi, S.; Chaisanguanthum, K. S.; Morii, M.; Wu, J.; Dubitzky, R. S.; Marks, J.; Schenk, S.; Uwer, U.; Bard, D. J.; Dauncey, P. D.; Flack, R. L.; Nash, J. A.; Nikolich, M. B.; Panduro Vazquez, W.; Behera, P. K.; Chai, X.; Charles, M. J.; Mallik, U.; Meyer, N. T.; Ziegler, V.; Cochran, J.; Crawley, H. B.; Dong, L.; Eyges, V.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gritsan, A. V.; Guo, Z. J.; Lae, C. K.; Denig, A. G.; Fritsch, M.; Schott, G.; Arnaud, N.; Bquilleux, J.; Davier, M.; Grosdidier, G.; Hcker, A.; Lepeltier, V.; Le Diberder, F.; Lutz, A. M.; Pruvot, S.; Rodier, S.; Roudeau, P.; Schune, M. H.; Serrano, J.; Sordini, V.; Stocchi, A.; Wang, W. F.; Wormser, G.; Lange, D. J.; Wright, D. M.; Chavez, C. A.; Forster, I. J.; Fry, J. R.; Gabathuler, E.; Gamet, R.; Hutchcroft, D. E.; Payne, D. J.; Schofield, K. C.; Touramanis, C.; Bevan, A. J.; George, K. A.; di Lodovico, F.; Menges, W.; Sacco, R.; Cowan, G.; Flaecher, H. U.; Hopkins, D. A.; Jackson, P. S.; McMahon, T. R.; Salvatore, F.; Wren, A. C.; Brown, D. N.; Davis, C. L.; Allison, J.; Barlow, N. R.; Barlow, R. J.; Chia, Y. M.; Edgar, C. L.; Lafferty, G. D.; West, T. J.; Yi, J. I.; Anderson, J.; Chen, C.; Jawahery, A.; Roberts, D. A.; Simi, G.; Tuggle, J. M.; Blaylock, G.; Dallapiccola, C.; Hertzbach, S. S.; Li, X.; Moore, T. B.; Salvati, E.; Saremi, S.; Cowan, R.; Fisher, P. H.; Sciolla, G.; Sekula, S. J.; Spitznagel, M.; Taylor, F.; Yamamoto, R. K.; McLachlin, S. E.; Patel, P. M.; Robertson, S. H.; Lazzaro, A.; Palombo, F.; Bauer, J. M.; Cremaldi, L.; Eschenburg, V.; Godang, R.; Kroeger, R.; Sanders, D. A.; Summers, D. J.; Zhao, H. W.; Brunet, S.; Ct, D.; Simard, M.; Taras, P.; Viaud, F. B.; Nicholson, H.; de Nardo, G.; Fabozzi, F.; Lista, L.; Monorchio, D.; Sciacca, C.; Baak, M. A.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Losecco, J. M.; Benelli, G.; Corwin, L. A.; Gan, K. K.; Honscheid, K.; Hufnagel, D.; Kagan, H.; Kass, R.; Morris, J. P.; Rahimi, A. M.

2008-02-01

440

Stability of array spectroradiometers and their suitability for absolute calibrations  

NASA Astrophysics Data System (ADS)

An investigation of the short- and long-term stability of various low-end and high-end array spectroradiometers is presented. Potentially weak points of array spectroradiometers with respect to their suitability for absolute calibrations are pointed out. The influence of ambient conditions on relevant instrumental characteristics and their temporal stability is discussed. It is shown that the temporal stability of some instruments can be significantly affected by high ambient humidity. Most important ambient temperature effects on instrument properties are also discussed.

Nevas, Saulius; Teuber, Annette; Sperling, Armin; Lindemann, Matthias

2012-04-01

441

Absolute calibration in grazing incidence interferometry via rotational averaging  

SciTech Connect

Interferometry in grazing incidence can be used to test cylindrical mantle surfaces. The absolute accuracy of the resulting surface profiles is limited by systematic wavefront aberrations caused in the interferometer, in particular due to an inversion of the test wavefront in an interferometer using diffractive beam splitters. For cylindrical specimens, a calibration method using four positions has therefore been investigated. This test is combined with another method of optical metrology: the rotational averaging procedure. The implementation for grazing incidence is described and measurement results for hollow cylinders are presented. The gain in accuracy is demonstrated.

Mantel, Klaus; Lamprecht, Juergen; Lindlein, Norbert; Schwider, Johannes

2006-06-01

442

Absolute cross-section normalization of magnetic neutron scattering data.  

PubMed

We discuss various methods to obtain the resolution volume for neutron scattering experiments, in order to perform absolute normalization on inelastic magnetic neutron scattering data. Examples from previous experiments are given. We also try to provide clear definitions of a number of physical quantities which are commonly used to describe neutron magnetic scattering results, including the dynamic spin correlation function and the imaginary part of the dynamic susceptibility. Formulas that can be used for general purposes are provided and the advantages of the different normalization processes are discussed. PMID:24007078

Xu, Guangyong; Xu, Zhijun; Tranquada, J M

2013-08-01

443

Precision Absolute Beam Current Measurement of Low Power Electron Beam  

SciTech Connect

Precise measurements of low power CW electron beam current for the Jefferson Lab Nuclear Physics program have been performed using a Tungsten calorimeter. This paper describes the rationale for the choice of the calorimeter technique, as well as the design and calibration of the device. The calorimeter is in use presently to provide a 1% absolute current measurement of CW electron beam with 50 to 500 nA of average beam current and 1-3 GeV beam energy. Results from these recent measurements will also be presented.

M.M. Ali, M.E. Bevins, P. Degtiarenko, A. Freyberger, G.A. Krafft

2012-11-01

444

Electromagnetic hydrophone with tomographic system for absolute velocity field mapping  

NASA Astrophysics Data System (ADS)

The velocity and pressure of an ultrasonic wave can be measured by an electromagnetic hydrophone made of a thin wire and a magnet. The ultrasonic wave vibrates the wire inside a magnetic field, inducing an electrical current. Previous articles reported poor spatial resolution of comparable hydrophones along the axis of the wire. In this study, submillimetric spatial resolution has been achieved by using a tomographic method. Moreover, a physical model is presented for obtaining absolute measurements. A pressure differential of 8% has been found between piezoelectric and electromagnetic hydrophone measurements. These characteristics show this technique as an alternative to standard hydrophones.

Grasland-Mongrain, Pol; Mari, Jean-Martial; Gilles, Bruno; Chapelon, Jean-Yves; Lafon, Cyril

2012-06-01

445

Lens transmission measurement for an absolute radiation thermometer  

NASA Astrophysics Data System (ADS)

The lens transmission for the National Institute of Metrology of China absolute radiation thermometer is measured by a hybrid method. The results of the lens transmission measurements are 99.002% and 86.792% for filter radiometers with center wavelengths 633 nm and 900 nm, respectively. These results, after correcting for diffraction factors and the size-of-source effect when the lens is incorporated within the radiometer, can be used for measurement of thermodynamic temperature. The expanded uncertainty of the lens transmission measurement system has been evaluated. It is 1.310-3 at 633 nm and 900 nm, respectively.

Hao, X.; Yuan, Z.; Lu, X.

2013-09-01

446

Two-mode interference measurement for nanometer accuracy absolute ranging.  

PubMed

We demonstrate a laser ranging scheme that uses a high-frequency modulated beam to achieve subnanometer precision by the combined use of interferometric and time-of-flight measurements. We first describe how the absolute distance is extracted from a two-mode interference signal. In particular, we show that the signal, which presents both optical and synthetic wavelength scales, allows one to achieve nanometer-scale accuracy, despite the significant long-term phase drifts in the 20 GHz detection chains. We present results obtained with the telemeter implemented for a distance of about four meters, obtained by folding the laser beam path to the target. PMID:23381411

Phung, Duy-Ha; Alexandre, Christophe; Lintz, Michel

2013-02-01

447

Determination of Absolute Configuration Using Kinetic Resolution Catalysts  

PubMed Central

A new method was developed to assign the absolute configuration of molecules using kinetic resolution catalysts. Secondary alcohols were acylated in the presence of Birmans S-HBTM and R-HBTM catalysts, and the fast reacting catalyst was identified by NMR analysis of the reaction mixture. A mnemonic was developed to assign configuration based on the identity of the fast-reacting catalyst. The method uses only 13 mg of alcohol, and it is more convenient than the Mosher method. The kinetic resolution strategy may be extended to other classes of molecules.

Wagner, Alexander J.; David, Jonathan G.

2011-01-01

448

Relative and absolute ages of Galactic globular clusters  

NASA Astrophysics Data System (ADS)

We present a review of the latest work concerned with the relative and absolute ages of the Galactic globular clusters (GCs). Relative age-dating techniques generally divide into two types - those that measure a magnitude difference between two features in the color-magnitude diagram (i.e. Vertical Methods) and those that rely on color differences in the color-magnitude diagram (i.e. Horizontal Methods). Both types of diagnostics have been successfully applied and generally reach the same conclusions. Galactic GCs exhibit a mean age range of ~3 Gyr, smaller (or nonexistent) for metal-poor clusters and larger (as much as 6 Gyr) for metal-rich ones. Generally speaking, the inner-halo GCs are older and more uniform in age as compared with those outside of the solar circle. Furthermore, the tendency of GCs with predominantly red horizontal branches (HBs) located in the outer halo to be preferentially younger than those with bluer HBs closer to the Galactic center suggests that age is the second parameter which, in addition to metal abundance, controls the HB morphology. In particular, we present additional compelling evidence supporting this assertion using a detailed examination of new photometry for the classic second-parameter cluster pair NGC 288 and NGC 362. Moving on to the absolute ages, we note that the absolute ages of the most metal-poor Galactic GCs sets a lower limit on the age of the Universe. The preferred age indicator for absolute ages is the luminosity of the main-sequence turnoff because most theoretical models agree on the onset of hydrogen exhaustion in the cores of low-mass stars. Based on the technique of main-sequence fitting to field subdwarfs with Hipparcos parallaxes, we find an age of 11.6+1.4-1.1 Gyr for four metal-poor GCs with deep color-magnitude diagrams on a consistent photometric scale; this age is consistent with the results of a number of previous investigations.

Sarajedini, Ata

2009-06-01

449

Determination of absolute chirality using resonant X-ray diffraction  

NASA Astrophysics Data System (ADS)

We have demonstrated that resonant diffraction experiments using the circularly polarized X-ray beam absolutely determines the crystal chirality. Both berlinite and quartz crystals belonging to space group P3221 show higher azimuth-constant intensity for the negative (-) helicity beam than that for the the positive (+) helicity beam for space-group forbidden reflection 001. The relation is opposite for quartz crystal belonging to space group P3121. Theoretical calculation shows that this relation completely agrees with the experimental findings for the enantiomorphic space-group pair P3121 and P3221. This method is applicable to chiral motifs that occur in biomolecules, liquid crystals, ferroelectrics, and multiferroics, etc.

Tanaka, Y.; Lovesey, S. W.

2012-06-01

450

Absolute ?-to-ground band transition strengths in 154Sm  

NASA Astrophysics Data System (ADS)

Low-lying collective states of 154Sm are studied via the 12C(154Sm,154Sm*) Coulomb excitation reaction at 85% of the Coulomb barrier (570 MeV) using the Gammasphere Ge-detector array. Absolute transition strengths are obtained from the Coulomb excitation cross sections deduced from the relative ?-ray yields. The results include transition strengths for E2 decays of energy levels in the low-spin part of the first excited K?=0+ rotational band of 154Sm. The agreement of these results with the confined ?-soft rotor model predictions establishes the assignment of this band as a ? band.

Mller, T.; Pietralla, N.; Rainovski, G.; Ahn, T.; Bauer, C.; Carpenter, M. P.; Coquard, L.; Janssens, R. V. F.; Leske, J.; Lister, C. J.; McCutchan, E. A.; Mller, O.; Seweryniak, D.; Zhu, S.

2012-09-01

451

Spatially resolved absolute spectrophotometry of Saturn - 3390 to 8080 A  

NASA Astrophysics Data System (ADS)

A series of spatially resolved absolute spectrophotometric measurements of Saturn was conducted for the expressed purpose of calibrating the data obtained with the Imaging Photopolarimeter (IPP) on Pioneer 11 during its recent encounter with Saturn. All observations reported were made at the Mt. Wilson 1.5-m telescope, using a 1-m Ebert-Fastie scanning spectrometer. Spatial resolution was 1.92 arcsec. Photometric errors are considered, taking into account the fixed error, the variable error, and the composite error. The results are compared with earlier observations, as well as with synthetic spectra derived from preliminary physical models, giving attention to the equatorial region and the South Temperate Zone.

Bergstralh, J. T.; Orton, G. S.; Diner, D. J.; Baines, K. H.; Neff, J. S.; Allen, M. A.

1981-04-01

452

Absolute configuration and 1H NMR characterization of rosmaridiphenol diacetate.  

PubMed

The correction of patented structure 1 of rosmaridiphenol, an antioxidant isolated from rosemary, Rosmarinus officinalis, was made recently. The correct structure is proposed as 11,12-dihydroxy-8,11,13-icetexatrien-1-one (2a) based on 2D NMR data. In order to further support the structure, this work reports the single-crystal X-ray analysis, the complete (1)H NMR assignment by full spin-spin simulation, and the absolute configuration of the diacetate 2b derived via vibrational circular dicroism measurements in comparison with density functional theory calculated data. PMID:22424272

Muoz, Marcelo A; Perez-Hernandez, Nury; Pertino, Mariano W; Schmeda-Hirschmann, Guillermo; Joseph-Nathan, Pedro

2012-03-16

453

Absolute magnetic helicity and the cylindrical magnetic field  

SciTech Connect

The different magnetic helicities conserved under conditions of perfect electrical conductivity are expressions of the fundamental property that every evolving fluid surface conserves its net magnetic flux. This basic hydromagnetic point unifies the well known Eulerian helicities with the Lagrangian helicity defined by the conserved fluxes frozen into a prescribed set of disjoint toroidal tubes of fluid flowing as a permanent partition of the entire fluid [B. C. Low, Astrophys. J. 649, 1064 (2006)]. This unifying theory is constructed from first principles, beginning with an analysis of the Eulerian and Lagrangian descriptions of fluids, separating the ideas of fluid and magnetic-flux tubes and removing the complication of the magnetic vector potential's free gauge from the concept of helicity. The analysis prepares for the construction of a conserved Eulerian helicity, without that gauge complication, to describe a 3D anchored flux in an upright cylindrical domain, this helicity called absolute to distinguish it from the well known relative helicity. In a version of the Chandrasekhar-Kendall representation, the evolving field at any instant is a unique superposition of a writhed, untwisted axial flux with a circulating flux of field lines all closed and unlinked within the cylindrical domain. The absolute helicity is then a flux-weighted sum of the writhe of that axial flux and its mutual linkage with the circulating flux. The absolute helicity is also conserved if the frozen-in field and its domain are continuously deformed by changing the separation between the rigid cylinder-ends with no change of cylinder radius. This hitherto intractable cylindrical construction closes a crucial conceptual gap for the fundamentals to be complete at last. The concluding discussion shows the impact of this development on our understanding of helicity, covering (i) the helicities of wholly contained and anchored fields; (ii) the Eulerian and Lagrangian descriptions of field evolution; (iii) twist as a topological property of solenoidal fields versus the linkage properties of open and closed discrete curves treated by Gauss, Caligarneau, Berger, and Prior; and (iv) the change of absolute helicity by resistive diffusion. These are important hydromagnetic properties of twisted magnetic fields in the million-degree hot, highly conducting corona of the Sun.

Low, B. C. [High Altitude Observatory, National Center for Atmospheric Research, Boulder, Colorado 80307 (United States)

2011-05-15

454

Absolute Oxygenation Metabolism Measurements Using Magnetic Resonance Imaging  

PubMed Central

Cerebral oxygen metabolism plays a critical role in maintaining normal function of the brain. It is the primary energy source to sustain neuronal functions. Abnormalities in oxygen metabolism occur in various neuro-pathologic conditions such as ischemic stroke, cerebral trauma, cancer, Alzheimers disease and shock. Therefore, the ability to quantitatively measure tissue oxygenation and oxygen metabolism is essential to the understanding of pathophysiology and treatment of various diseases. The focus of this review is to provide an introduction of various blood oxygenation level dependent (BOLD) contrast methods for absolute measurements of tissue oxygenation, including both magnitude and phase image based approaches. The advantages and disadvantages of each method are discussed.

An, Hongyu; Liu, Qingwei; Eldeniz, Cihat; Lin, Weili

2011-01-01

455

Absolute measurement of hadronic branching fractions of the Ds+ meson.  

PubMed

The branching fractions of D(s)(+/-) meson decays serve to normalize many measurements of processes involving charm quarks. Using 298 pb(-1) of e(+)e(-) collisions recorded at a center of mass energy of 4.17 GeV, we determine absolute branching fractions for eight D(s)(+/-) decays with a double tag technique. In particular we determine the branching fraction B(D(s)(+)-->K(-)K(+}pi(+))=(5.50+/-0.23+/-0.16)%, where the uncertainties are statistical and systematic, respectively. We also provide partial branching fractions for kinematic subsets of the K(-)K(+)pi(+) decay mode. PMID:18518186

Alexander, J P; Berkelman, K; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Mehrabyan, S; Lowrey, N; Selen, M; White, E J; Wiss, J; Mitchell, R E; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A; Libby, J; Powell, A; Wilkinson, G; Ecklund, K M; Love, W; Savinov, V; Lopez, A; Mendez, H; Ramirez, J; Ge, J Y; Miller, D H; Sanghi, B; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Mountain, R; Nisar, S; Randrianarivony, K; Sultana, N; Skwarnicki, T; Stone, S; Wang, J C; Zhang, L M; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Rademacker, J; Asner, D M; Edwards, K W; Naik, P; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L

2008-04-23

456

Self-attraction effect and correction on three absolute gravimeters  

NASA Astrophysics Data System (ADS)

The perturbations of the gravitational field due to the mass distribution of an absolute gravimeter have been studied. The so-called self-attraction effect (SAE) is crucial for the measurement accuracy, especially for International Comparisons, and for the uncertainty budget evaluation. Three instruments have been analysed: MPG-2, FG5-238 and IMGC-02. The SAE has been calculated using a numerical method based on finite element method simulation. The modelled effect has been treated as an additional vertical gravity gradient. The self-attraction correction (SAC) to be applied to the computed g value is of the order of 1 10-8 m s-2.

Biolcati, E.; Svitlov, S.; Germak, A.

2012-08-01

457

Quantum Bath Refrigeration towards Absolute Zero: Challenging the Unattainability Principle  

NASA Astrophysics Data System (ADS)

A minimal model of a quantum refrigerator, i.e., a periodically phase-flipped two-level system permanently coupled to a finite-capacity bath (cold bath) and an infinite heat dump (hot bath), is introduced and used to investigate the cooling of the cold bath towards absolute zero (T=0). Remarkably, the temperature scaling of the cold-bath cooling rate reveals that it does not vanish as T?0 for certain realistic quantized baths, e.g., phonons in strongly disordered media (fractons) or quantized spin waves in ferromagnets (magnons). This result challenges Nernsts third-law formulation known as the unattainability principle.

Kol?, M.; Gelbwaser-Klimovsky, D.; Alicki, R.; Kurizki, G.

2012-08-01

458

Optimized replica gas estimation of absolute integrals and partition functions.  

SciTech Connect

In contrast with most Monte Carlo integration algorithms, which are used to estimate ratios, the replica gas identities recently introduced by Adib enable the estimation of absolute integrals and partition functions using multiple copies of a system and normalized transition functions. Here, an optimized form is presented. After generalizing a replica gas identity with an arbitrary weighting function, we obtain a functional form that has the minimal asymptotic variance for samples from two replicas and is provably good for a larger number. This equation is demonstrated to improve the convergence of partition function estimates in a two-dimensional Ising model.

Minh, D. (Biosciences Division)

2010-01-01

459

Diffractive incremental and absolute coding principle for optical rotary sensors.  

PubMed

Rotary sensors are an essential component in numerous applications where a rotation movement has to be detected. With optical encoders, a high angular resolution can be achieved. As a disadvantage, the resolution enhancement is associated with increasing cost. To overcome this issue, a coding principle is presented that uses a diffractive solid measure on a microstructured plastic disc. Like a DVD, this encoder disc can be manufactured in a cost effective injection molding process. For this approach, a differential incremental code, as well as an absolute code, has been developed. PMID:21947000

Hopp, David; Pruss, Christof; Osten, Wolfgang; Seybold, Jonathan; Fritz, Karl-Peter; Botzelmann, Tim; Mayer, Volker; Kck, Heinz

2011-09-10

460

Thermal engine  

SciTech Connect

A thermal engine utilizing a strip of nitinol material or other thermally responsive shape memory effect material to drive a reciprocating output shaft, said strip of material forming a common wall between two different alternating temperature sources which thermally cycle the material.

Karnes, T.E.; Trupin, R.J.

1984-01-03

461

Excited-state structure and photochemical ring-opening dynamics of 1,3,5-cyclo-octatriene from absolute resonance Raman intensities  

Microsoft Academic Search

Absolute resonance Raman cross sections are measured for 1,3,5-cyclo-octatriene (COT) in cyclohexane with excitation from 325 to 200 nm. These intensities and the absorption spectrum are modeled using a fully thermalized time-correlator theory to quantitate the excited-state equilibrium geometry displacements along 19 Raman-active normal modes. The resonance Raman spectra show significant intensity in low-frequency modes corresponding to planarization of the

Mary K. Lawless; Richard A. Mathies

1994-01-01

462

A large aperture blackbody bath for calibration of thermal imagers  

NASA Astrophysics Data System (ADS)

Thermal imagers are becoming widely used instruments for noncontact absolute temperature measurements as opposed to previous practice when they were mostly used to measure temperature differences. To assure accurate and reliable absolute temperature measurements, a calibration procedure including evaluation of the thermal imager entire field of view (FOV) is needed. The challenge was to construct a large aperture blackbody, covering the complete FOV of the thermal imager and having better stability and non-uniformity than the thermal sensitivity of the imager. The blackbody calibration bath was designed on hypothesis analogous to the multi zone furnace, where the role of electrical heaters was superseded by electrically controlled valves. The experimental work showed that the designed system enables traceable calibration of thermal imagers in the temperature range from 10 to 70 C with the expanded uncertainty of 0.2 C, while further investigations are needed to cover ranges beyond that.

Miklavec, A.; Punik, I.; Batagelj, V.; Drnovek, J.

2013-02-01

463

Highly resolved absolute cross-sections for dissociative electron attachment to SF5CF3  

NASA Astrophysics Data System (ADS)

Using two complementary experimental methods, we have measured partial (mass-resolved) cross-sections for dissociative electron attachment to the molecule trifluoromethyl sulfurpentafluoride (SF5CF3) at the gas temperature TG = 300 K over a broad range of electron energies (E = 0.001-12 eV). The absolute scale for these cross-sections was obtained with reference to the thermal (T = 300 K) rate coefficient for anion formation (8.0(3) 10-8 cm3 s-1). Below 1 eV, SF5- is the dominant product anion and formed through the lowest anion state which cuts the neutral SF5CF3 potential close to the S-C equilibrium distance. The highly resolved laser photoelectron attachment data exhibit a downward Wigner cusp at 86 meV, indicating that the [nu]4(a1) vibrational mode is important for the primary attachment dynamics. Both SF5- and F- anions are formed with similar yields through the first excited resonance located near 3.6 eV. Towards higher energies, the anions CF3-, SF4-, and SF3- are also produced. Summation of the partial cross-sections yields a total absolute cross-section for anion formation over the energy range 0.001-12 eV. This is used to calculate the dependence of the rate coefficient for dissociative electron attachment over a broad range of electron temperatures for the fixed gas temperature TG = 300 K; good agreement is found between the calculated values and those obtained in a drift tube experiment. In addition to the experimental work, semiempirical R-matrix calculations have been carried out for the energy dependence of the cross-section for SF5- formation. The experimental findings are semi-quantitatively recovered.

Graupner, K.; Graham, L. M.; Field, T. A.; Mayhew, C. A.; Fabrikant, I. I.; Miller, T. M.; Braun, M.; Ruf, M. W.; Hotop, H.

2008-11-01

464

Permanent rotations of a heavy rigid body on an absolutely rough horizontal plane  

Microsoft Academic Search

Conditions for the existence and stability of permanent rotations of a heavy rigid body on an absolutely rough horizontal plane are obtained. The present case is compared with that of the permanent rotations of a body on an absolutely smooth plane and of a body with a fixed point. In the case of an absolutely rough plane, a stability of

A. V. Karapetian

1981-01-01

465

New chiral anisotropic reagents for determining the absolute configuration of carboxylic acids  

Microsoft Academic Search

Enantiomers of phenylglycine dimethylamide (PGDA) and phenylglycine methyl ester (PGME) were prepared as the reagents for determining the absolute configuration of carboxyl acids of type I. Each enantiomer of PGDA and PGME was condensed with several carboxylic acids, the absolute configuration of which is known. The absolute configuration of the carboxylic acids, predicted by ?? values (?? = ?S ?

Yuriko Nagai; Takenori Kusumi

1995-01-01

466

Estimation and interpretation of models of absolute risk from epidemiologic data, including family-based studies  

Microsoft Academic Search

Absolute risk is the chance that a person with given risk factors and free of the disease of interest at age a will be diagnosed with that disease in the interval (a, a + ?]. Absolute risk is sometimes called cumulative incidence. Absolute risk is a crude risk because it is reduced by the chance\\u000a that the person will die

Mitchell H. Gail

2008-01-01

467

MSTAR: an absolute metrology system with submicrometer accuracy  

NASA Astrophysics Data System (ADS)

Laser metrology systems are a key component of stellar interferometers, used to monitor path lengths and dimensions internal to the instrument. Most interferometers use 'relative' metrology, in which the integer number of wavelengths along the path is unknown, and the measurement of length is ambiguous. Changes in the path length can be measured relative to an initial calibration point, but interruption of the metrology beam at any time requires a re-calibration of the system. The MSTAR sensor (Modulation Sideband Technology for Absolute Ranging) is a new system for measuring absolute distance, capable of resolving the integer cycle ambiguity of standard interferometers, and making it possible to measure distance with sub-nanometer accuracy. We describe the design of the system, show results for target distances up to 1 meter, and demonstrate how the system can be scaled to kilometer-scale distances. In recent experiments, we have used white light interferometry to augment the 'truth' measurements and validate the zero-point of the system. MSTAR is a general-purpose tool for conveniently measuring length with much greater accuracy than was previously possible, and has a wide range of possible applications.

Lay, Oliver P.; Dubovitsky, Serge; Peters, Robert D.; Burger, Johan; Steier, Willian H.; Ahn, Seh-Won; Fetterman, Harrold R.

2004-10-01

468

Absolute free energies of biomolecules from unperturbed ensembles.  

PubMed

Computing the absolute free energy of a macromolecule's structural state, F, is a challenging problem of high relevance. This study presents a method that computes F using only information from an unperturbed simulation of the macromolecule in the relevant conformational state, ensemble, and environment. Absolute free energies produced by this method, dubbed Valuation of Local Configuration Integral with Dynamics (VALOCIDY), enable comparison of alternative states. For example, comparing explicitly solvated and vaporous states of amino acid side-chain analogs produces solvation free energies in good agreement with experiments. Also, comparisons between alternative conformational states of model heptapeptides (including the unfolded state) produce free energy differences in agreement with data from ?s molecular-dynamics simulations and experimental propensities. The potential of using VALOCIDY in computational protein design is explored via a small design problem of stabilizing a ?-turn structure. When VALOCIDY-based estimation of folding free energy is used as the design metric, the resulting sequence folds into the desired structure within the atomistic force field used in design. The VALOCIDY-based approach also recognizes the distinct status of the native sequence regardless of minor details of the starting template structure, in stark contrast with a traditional fixed-backbone approach. 2013 Wiley Periodicals, Inc. PMID:24132787

Grigoryan, Gevorg

2013-10-16

469

Closed-loop step motor control using absolute encoders  

SciTech Connect

A multi-axis, step motor control system was developed to accurately position and control the operation of a triple axis spectrometer at the High Flux Isotope Reactor (HFIR) located at Oak Ridge National Laboratory. Triple axis spectrometers are used in neutron scattering and diffraction experiments and require highly accurate positioning. This motion control system can handle up to 16 axes of motion. Four of these axes are outfitted with 17-bit absolu