Science.gov

Sample records for lubbockihexapoda diplura high

  1. The mitochondrial genomes of Campodea fragilis and C. lubbocki(Hexapoda: Diplura): high genetic divergence in a morphologically uniformtaxon

    SciTech Connect

    Podsiadlowski, L.; Carapelli, A.; Nardi, F.; Dallai, R.; Koch,M.; Boore, J.L.; Frati, F.

    2005-12-01

    Mitochondrial genomes from two dipluran hexapods of the genus Campodea have been sequenced. Gene order is the same as in most other hexapods and crustaceans. Secondary structures of tRNAs reveal specific structural changes in tRNA-C, tRNA-R, tRNA-S1 and tRNA-S2. Comparative analyses of nucleotide and amino acid composition, as well as structural features of both ribosomal RNA subunits, reveal substantial differences among the analyzed taxa. Although the two Campodea species are morphologically highly uniform, genetic divergence is larger than expected, suggesting a long evolutionary history under stable ecological conditions.

  2. Brain anatomy in Diplura (Hexapoda)

    PubMed Central

    2012-01-01

    Background In the past decade neuroanatomy has proved to be a valuable source of character systems that provide insights into arthropod relationships. Since the most detailed description of dipluran brain anatomy dates back to Hanström (1940) we re-investigated the brains of Campodea augens and Catajapyx aquilonaris with modern neuroanatomical techniques. The analyses are based on antibody staining and 3D reconstruction of the major neuropils and tracts from semi-thin section series. Results Remarkable features of the investigated dipluran brains are a large central body, which is organized in nine columns and three layers, and well developed mushroom bodies with calyces receiving input from spheroidal olfactory glomeruli in the deutocerebrum. Antibody staining against a catalytic subunit of protein kinase A (DC0) was used to further characterize the mushroom bodies. The japygid Catajapyx aquilonaris possesses mushroom bodies which are connected across the midline, a unique condition within hexapods. Conclusions Mushroom body and central body structure shows a high correspondence between japygids and campodeids. Some unique features indicate that neuroanatomy further supports the monophyly of Diplura. In a broader phylogenetic context, however, the polarization of brain characters becomes ambiguous. The mushroom bodies and the central body of Diplura in several aspects resemble those of Dicondylia, suggesting homology. In contrast, Archaeognatha completely lack mushroom bodies and exhibit a central body organization reminiscent of certain malacostracan crustaceans. Several hypotheses of brain evolution at the base of the hexapod tree are discussed. PMID:23050723

  3. First Alaskan records and a significant northern range extension for two species of Diplura (Diplura, Campodeidae)

    PubMed Central

    Sikes, Derek S.; Allen, Robert T.

    2016-01-01

    Abstract Species in the class Diplura are recorded from Alaska for the first time. Two species, Tricampa rileyi Silvestri from Dall and Prince of Wales Islands in the Alexander Archipelago of Southeast Alaska and Metriocampa allocerca Conde & Geeraert from near Quartz Lake, southeast of Fairbanks, both in the family Campodeidae, are documented based on recently collected specimens deposited in the University of Alaska Museum Insect Collection. A brief review of the history of the documentation of the Alaskan soil microarthropod fauna is provided, as well as discussion of possible glacial refugia. PMID:27047242

  4. New Species of Campodeidae (Diplura) from Mexican caves.

    PubMed

    Sendra, Alberto; Palacios, Jose; Garcia, Arturo; Montejo, Maira

    2016-01-01

    Six new taxa of Campodeidae (Diplura) are described in the genera Litocampa, Juxtlacampa, Oncinocampa, and Tachycampa. We also redescribe the interesting species Juxtlacampa juxtlahucensis Wygodzinsky, 1944 from Juxtlahuaca cave in Guerrero, Mexico. All of these taxa are cave-dwelling species with more or less noticeable troglobiomorphic features They inhabit the subterranean ecosystem in six limestone massifs and one lava tube cave in the central states of Mexico. Four of these species are included in the "tachycampoide" group and one species in the "podocampoide" group (sensu Bareth & Conde). Nine species already known in Central and South America of the "tachycampoide" group, in such poorly-sampled regions compared with the eight species in the well-sampled Mediterranean region (Ibero-Sardinia and north Africa), suggest an American origin for this group. PMID:27395944

  5. Comparative Analysis of Mitochondrial Genomes in Diplura (Hexapoda, Arthropoda): Taxon Sampling Is Crucial for Phylogenetic Inferences

    PubMed Central

    Chen, Wan-Jun; Koch, Markus; Mallatt, Jon M.; Luan, Yun-Xia

    2014-01-01

    Two-pronged bristletails (Diplura) are traditionally classified into three major superfamilies: Campodeoidea, Projapygoidea, and Japygoidea. The interrelationships of these three superfamilies and the monophyly of Diplura have been much debated. Few previous studies included Projapygoidea in their phylogenetic considerations, and its position within Diplura still is a puzzle from both morphological and molecular points of view. Until now, no mitochondrial genome has been sequenced for any projapygoid species. To fill in this gap, we determined and annotated the complete mitochondrial genome of Octostigma sinensis (Octostigmatidae, Projapygoidea), and of three more dipluran species, one each from the Campodeidae, Parajapygidae, and Japygidae. All four newly sequenced dipluran mtDNAs encode the same set of genes in the same gene order as shared by most crustaceans and hexapods. Secondary structure truncations have occurred in trnR, trnC, trnS1, and trnS2, and the reduction of transfer RNA D-arms was found to be taxonomically correlated, with Campodeoidea having experienced the most reduction. Partitioned phylogenetic analyses, based on both amino acids and nucleotides of the protein-coding genes plus the ribosomal RNA genes, retrieve significant support for a monophyletic Diplura within Pancrustacea, with Projapygoidea more closely related to Campodeoidea than to Japygoidea. Another key finding is that monophyly of Diplura cannot be recovered unless Projapygoidea is included in the phylogenetic analyses; this explains the dipluran polyphyly found by past mitogenomic studies. Including Projapygoidea increased the sampling density within Diplura and probably helped by breaking up a long-branch-attraction artifact. This finding provides an example of how proper sampling is significant for phylogenetic inference. PMID:24391151

  6. Redescription of arenicolous dipluran Parajapyx pauliani (Diplura, Parajapygidae) and DNA barcoding analyses of Parajapyx from China

    PubMed Central

    Bu, Yun; Gao, Yan; Potapov, Mikhail B.; Luan, Yun-Xia

    2012-01-01

    Abstract Littoral dipluran Parajapyx pauliani Pagés, 1959 was redescribed based on the specimens collected in Hainan Island, South China. The littoral habitat was confirmed for the species, as the first report of arenicolous dipluran in China. DNA barcoding fragment was sequenced for five Parajapyx species (18 individuals) from China, and this is the first report on DNA barcodes used for dipluran identification. The mean intra- and interspecific divergencesare 1.9% and 19.1% respectively. Synonymy of Parajapyx paucidentis and Parajapyx isabellae was confirmed. PMID:23129979

  7. High Tech High.

    ERIC Educational Resources Information Center

    Hardy, Lawrence

    2001-01-01

    In an era of high-stakes testing and prescriptive teaching styles, a San Diego charter high school embraces project learning, multilevel classrooms, and video portfolios of student work. The school lacks dining, music, and athletic facilities, but features hefty teacher salaries, student freedom, and real-world problem solving. (MLH)

  8. High arch

    MedlinePlus

    ... is on the back and balls of the foot (metatarsals head). Your health care provider will check to see if the high ... Call your health care provider if you suspect you are having foot pain related to high arches.

  9. High PRF high current switch

    DOEpatents

    Moran, Stuart L.; Hutcherson, R. Kenneth

    1990-03-27

    A triggerable, high voltage, high current, spark gap switch for use in pu power systems. The device comprises a pair of electrodes in a high pressure hydrogen environment that is triggered by introducing an arc between one electrode and a trigger pin. Unusually high repetition rates may be obtained by undervolting the switch, i.e., operating the trigger at voltages much below the self-breakdown voltage of the device.

  10. High arch

    MedlinePlus

    Pes cavus; High foot arch ... High foot arches are much less common than flat feet. They are more likely to be caused by a ... stress is placed on the section of the foot between the ankle and toes (metatarsals). This condition ...

  11. High Class

    ERIC Educational Resources Information Center

    Waldecker, Mark

    2005-01-01

    Education administrators make buying decisions for furniture based on many factors. Cost, durability, functionality, safety and aesthetics represent just a few. Those issues always will be important, but gaining greater recognition in recent years has been the role furniture plays in creating positive, high-performance learning environments. The…

  12. Flying High

    ERIC Educational Resources Information Center

    Litvin, Margaret

    2000-01-01

    Nearly a decade ago, the Montreal School of Aerospace Trades became part of a massive education reform that takes most career education in the province out of comprehensive high schools and invests millions of dollars in specialized vocational schools. Through education-industry partnerships, these schools helping to change the image of vocational…

  13. High Stakes

    ERIC Educational Resources Information Center

    Elgin, Catherine Z.

    2004-01-01

    I discuss the contributions of Harvey Siegel, Francis Schrag and Randall Curren to this volume. Their articles cast in bold relief the relation of High Stakes Testing to the goals of education, the nature of mind and the demands of justice. I argue that the connections are deep, but that the considerations these authors raise do not show that High…

  14. Highly dominating, highly authoritarian personalities.

    PubMed

    Altemeyer, Bob

    2004-08-01

    The author considered the small part of the population whose members score highly on both the Social Dominance Orientation scale and the Right-Wing Authoritarianism scale. Studies of these High SDO-High RWAs, culled from samples of nearly 4000 Canadian university students and over 2600 of their parents and reported in the present article, reveal that these dominating authoritarians are among the most prejudiced persons in society. Furthermore, they seem to combine the worst elements of each kind of personality, being power-hungry, unsupportive of equality, manipulative, and amoral, as social dominators are in general, while also being religiously ethnocentric and dogmatic, as right-wing authoritarians tend to be. The author suggested that, although they are small in number, such persons can have considerable impact on society because they are well-positioned to become the leaders of prejudiced right-wing political movements. PMID:15279331

  15. High Poverty, High Performing Schools. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1997

    1997-01-01

    This theme issue includes four articles on high performance by poor Texas schools. In "Principal of National Blue Ribbon School Says High Poverty Schools Can Excel" (interview with Robert Zarate by Christie L. Goodman), the principal of Mary Hull Elementary School (San Antonio, Texas) describes how the high-poverty, high-minority school…

  16. Project Georgia High School/High Tech

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Georgia High School/High Tech has been developing a suggested curriculum for use in its programs. The purpose of this instructional material is to provide a basic curriculum format for teachers of High School/High Tech students. The curriculum is designed to implement QCC classroom instruction that encourages career development in technological fields through post-secondary education, paid summer internships, and exposure to experiences in high technology.

  17. High Blood Pressure (Hypertension)

    MedlinePlus

    ... Print Page Text Size: A A A Listen High Blood Pressure (Hypertension) Nearly 1 in 3 American adults has high ... weight. How Will I Know if I Have High Blood Pressure? High blood pressure is a silent problem — you ...

  18. Highly Anisotropic, Highly Transparent Wood Composites.

    PubMed

    Zhu, Mingwei; Song, Jianwei; Li, Tian; Gong, Amy; Wang, Yanbin; Dai, Jiaqi; Yao, Yonggang; Luo, Wei; Henderson, Doug; Hu, Liangbing

    2016-07-01

    For the first time, two types of highly anisotropic, highly transparent wood composites are demonstrated by taking advantage of the macro-structures in original wood. These wood composites are highly transparent with a total transmittance up to 90% but exhibit dramatically different optical and mechanical properties. PMID:27147136

  19. Project Georgia High School/High Tech

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The High School/High Tech initiative of the President's Committee on Employment of Disabilities, Georgia's application of the collaborative "Georgia Model" and NASA's commitment of funding have shown that opportunities for High School/High Tech students are unlimited. In Georgia, the partnership approach to meeting the needs of this program has opened doors previously closed. As the program grows and develops, reflecting the needs of our students and the marketplace, more opportunities will be available. Our collaboratives are there to provide these opportunities and meet the challenge of matching our students with appropriate education and career goals. Summing up the activities and outcomes of Project Georgia High School/High Tech is not difficult. Significant outcomes have already occurred in the Savannah area as a result of NASA's grant. The support of NASA has enabled Georgia Committee to "grow" High School/High Tech throughout the region-and, by example, the state. The success of the Columbus pilot project has fostered the proliferation of projects, resulting in more than 30 Georgia High School High Tech programs-with eight in the Savannah area.

  20. High Blood Pressure

    MedlinePlus

    ... version of this page please turn Javascript on. High Blood Pressure What Is High Blood Pressure? High blood pressure is a common disease in ... the heart, kidneys, brain, and eyes. Types of High Blood Pressure There are two main types of high blood ...

  1. High Blood Pressure

    MedlinePlus

    ... version High Blood Pressure Overview What is blood pressure? Blood pressure is the amount of force that your ... called your blood pressure. What is high blood pressure? High blood pressure (also called hypertension) occurs when your blood ...

  2. High blood pressure - infants

    MedlinePlus

    National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents. The fourth report on the diagnosis, evaluation, and treatment of high blood pressure in children and adolescents. Pediatrics . ...

  3. High blood sugar

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000332.htm High blood sugar To use the sharing features on this page, ... later when energy is needed. Symptoms of High Blood Sugar Symptoms of high blood sugar can include: Being ...

  4. High Blood Pressure

    MedlinePlus

    ... normal blood pressure 140/90 or higher is high blood pressure Between 120 and 139 for the top number, ... prehypertension. Prehypertension means you may end up with high blood pressure, unless you take steps to prevent it. High ...

  5. High Performance Networks for High Impact Science

    SciTech Connect

    Scott, Mary A.; Bair, Raymond A.

    2003-02-13

    This workshop was the first major activity in developing a strategic plan for high-performance networking in the Office of Science. Held August 13 through 15, 2002, it brought together a selection of end users, especially representing the emerging, high-visibility initiatives, and network visionaries to identify opportunities and begin defining the path forward.

  6. High strength high modulus ceramic fiber

    NASA Technical Reports Server (NTRS)

    Fetterolf, R. N.

    1972-01-01

    Low cost method was developed for producing high strength, high modulus, continuous ceramic oxide fibers. Process transforms inexpensive metallic salts into syrup-like liquids that can be fiberized at room temperatures. Resulting salt fibers are then converted to oxides by calcination at relatively low temperatures.

  7. High-Flying High-Poverty Schools

    ERIC Educational Resources Information Center

    American Educator, 2013

    2013-01-01

    In discussing socioeconomic integration before audiences, the author is frequently asked: What about high-poverty schools that do work? Don't they suggest that economic segregation isn't much of a problem after all? High-poverty public schools that beat the odds paint a heartening story that often attracts considerable media attention. In 2000,…

  8. Development of high strength, high temperature ceramics

    NASA Technical Reports Server (NTRS)

    Hall, W. B.

    1982-01-01

    Improvement in the high-pressure turbopumps, both fuel and oxidizer, in the Space Shuttle main engine were considered. The operation of these pumps is limited by temperature restrictions of the metallic components used in these pumps. Ceramic materials that retain strength at high temperatures and appear to be promising candidates for use as turbine blades and impellers are discussed. These high strength materials are sensitive to many related processing parameters such as impurities, sintering aids, reaction aids, particle size, processing temperature, and post thermal treatment. The specific objectives of the study were to: (1) identify and define the processing parameters that affect the properties of Si3N4 ceramic materials, (2) design and assembly equipment required for processing high strength ceramics, (3) design and assemble test apparatus for evaluating the high temperature properties of Si3N4, and (4) conduct a research program of manufacturing and evaluating Si3N4 materials as applicable to rocket engine applications.

  9. High pressure, high current, low inductance, high reliability sealed terminals

    DOEpatents

    Hsu, John S [Oak Ridge, TN; McKeever, John W [Oak Ridge, TN

    2010-03-23

    The invention is a terminal assembly having a casing with at least one delivery tapered-cone conductor and at least one return tapered-cone conductor routed there-through. The delivery and return tapered-cone conductors are electrically isolated from each other and positioned in the annuluses of ordered concentric cones at an off-normal angle. The tapered cone conductor service can be AC phase conductors and DC link conductors. The center core has at least one service conduit of gate signal leads, diagnostic signal wires, and refrigerant tubing routed there-through. A seal material is in direct contact with the casing inner surface, the tapered-cone conductors, and the service conduits thereby hermetically filling the interstitial space in the casing interior core and center core. The assembly provides simultaneous high-current, high-pressure, low-inductance, and high-reliability service.

  10. High Blood Pressure

    MedlinePlus

    ... page from the NHLBI on Twitter. Description of High Blood Pressure Español High blood pressure is a common disease ... defines high blood pressure severity levels. Stages of High Blood Pressure in Adults Stages Systolic (top number) Diastolic (bottom ...

  11. Bumball: Highly Engaging, Highly Inclusive, and Highly Entertaining

    ERIC Educational Resources Information Center

    Hall, Amber; Barney, David; Wilkinson, Carol

    2014-01-01

    Physical educators are always looking for new and exciting games and activities in which students can participate. This article describes Bumball, a high-intensity game that provides the opportunity for students to use many common game skills, such as hand-eye coordination, passing to a target, running, playing defense, and getting to an open…

  12. High-current, high-frequency capacitors

    NASA Technical Reports Server (NTRS)

    Renz, D. D.

    1983-01-01

    The NASA Lewis high-current, high-frequency capacitor development program was conducted under a contract with Maxwell Laboratories, Inc., San Diego, California. The program was started to develop power components for space power systems. One of the components lacking was a high-power, high-frequency capacitor. Some of the technology developed in this program may be directly usable in an all-electric airplane. The materials used in the capacitor included the following: the film is polypropylene, the impregnant is monoisopropyl biphenyl, the conductive epoxy is Emerson and Cuming Stycast 2850 KT, the foil is aluminum, the case is stainless steel (304), and the electrode is a modified copper-ceramic.

  13. High strength and high toughness steel

    DOEpatents

    Parker, Earl R.; Zackay, Victor F.

    1979-01-01

    A structural steel which possess both high strength and high toughness and has particular application of cryogenic uses. The steel is produced by the utilization of thermally induced phase transformation following heating in a three-phase field in iron-rich alloys of the Fe-Ni-Ti system, with a preferred composition of 12% nickel, 0.5% titanium, the remainder being iron.

  14. High strength, high ductility low carbon steel

    DOEpatents

    Koo, Jayoung; Thomas, Gareth

    1978-01-01

    A high strength, high ductility low carbon steel consisting essentially of iron, 0.05-0.15 wt% carbon, and 1-3 wt% silicon. Minor amounts of other constituents may be present. The steel is characterized by a duplex ferrite-martensite microstructure in a fibrous morphology. The microstructure is developed by heat treatment consisting of initial austenitizing treatment followed by annealing in the (.alpha. + .gamma.) range with intermediate quenching.

  15. High temperature, high power piezoelectric composite transducers.

    PubMed

    Lee, Hyeong Jae; Zhang, Shujun; Bar-Cohen, Yoseph; Sherrit, Stewart

    2014-01-01

    Piezoelectric composites are a class of functional materials consisting of piezoelectric active materials and non-piezoelectric passive polymers, mechanically attached together to form different connectivities. These composites have several advantages compared to conventional piezoelectric ceramics and polymers, including improved electromechanical properties, mechanical flexibility and the ability to tailor properties by using several different connectivity patterns. These advantages have led to the improvement of overall transducer performance, such as transducer sensitivity and bandwidth, resulting in rapid implementation of piezoelectric composites in medical imaging ultrasounds and other acoustic transducers. Recently, new piezoelectric composite transducers have been developed with optimized composite components that have improved thermal stability and mechanical quality factors, making them promising candidates for high temperature, high power transducer applications, such as therapeutic ultrasound, high power ultrasonic wirebonding, high temperature non-destructive testing, and downhole energy harvesting. This paper will present recent developments of piezoelectric composite technology for high temperature and high power applications. The concerns and limitations of using piezoelectric composites will also be discussed, and the expected future research directions will be outlined. PMID:25111242

  16. High Temperature, High Power Piezoelectric Composite Transducers

    PubMed Central

    Lee, Hyeong Jae; Zhang, Shujun; Bar-Cohen, Yoseph; Sherrit, StewarT.

    2014-01-01

    Piezoelectric composites are a class of functional materials consisting of piezoelectric active materials and non-piezoelectric passive polymers, mechanically attached together to form different connectivities. These composites have several advantages compared to conventional piezoelectric ceramics and polymers, including improved electromechanical properties, mechanical flexibility and the ability to tailor properties by using several different connectivity patterns. These advantages have led to the improvement of overall transducer performance, such as transducer sensitivity and bandwidth, resulting in rapid implementation of piezoelectric composites in medical imaging ultrasounds and other acoustic transducers. Recently, new piezoelectric composite transducers have been developed with optimized composite components that have improved thermal stability and mechanical quality factors, making them promising candidates for high temperature, high power transducer applications, such as therapeutic ultrasound, high power ultrasonic wirebonding, high temperature non-destructive testing, and downhole energy harvesting. This paper will present recent developments of piezoelectric composite technology for high temperature and high power applications. The concerns and limitations of using piezoelectric composites will also be discussed, and the expected future research directions will be outlined. PMID:25111242

  17. Structural mouthpart interaction evolved already in the earliest lineages of insects

    PubMed Central

    Blanke, Alexander; Rühr, Peter T.; Mokso, Rajmund; Villanueva, Pablo; Wilde, Fabian; Stampanoni, Marco; Uesugi, Kentaro; Machida, Ryuichiro; Misof, Bernhard

    2015-01-01

    In butterflies, bees, flies and true bugs specific mouthparts are in close contact or even fused to enable piercing, sucking or sponging of particular food sources. The common phenomenon behind these mouthpart types is a complex composed of several consecutive mouthparts which structurally interact during food uptake. The single mouthparts are thus only functional in conjunction with other adjacent mouthparts, which is fundamentally different to biting–chewing. It is, however, unclear when structural mouthpart interaction (SMI) evolved since this principle obviously occurred multiple times independently in several extant and extinct winged insect groups. Here, we report a new type of SMI in two of the earliest wingless hexapod lineages—Diplura and Collembola. We found that the mandible and maxilla interact with each other via an articulatory stud at the dorsal side of the maxillary stipes, and they are furthermore supported by structures of the hypopharynx and head capsule. These interactions are crucial stabilizing elements during food uptake. The presence of SMI in these ancestrally wingless insects, and its absence in those crustacean groups probably ancestral to insects, indicates that SMI is a groundplan apomorphy of insects. Our results thus contradict the currently established view of insect mouthpart evolution that biting–chewing mouthparts without any form of SMI are the ancestral configuration. Furthermore, SMIs occur in the earliest insects in a high anatomical variety. SMIs in stemgroup representatives of insects may have triggered efficient exploitation and fast adaptation to new terrestrial food sources much earlier than previously supposed. PMID:26203002

  18. Structural mouthpart interaction evolved already in the earliest lineages of insects.

    PubMed

    Blanke, Alexander; Rühr, Peter T; Mokso, Rajmund; Villanueva, Pablo; Wilde, Fabian; Stampanoni, Marco; Uesugi, Kentaro; Machida, Ryuichiro; Misof, Bernhard

    2015-08-01

    In butterflies, bees, flies and true bugs specific mouthparts are in close contact or even fused to enable piercing, sucking or sponging of particular food sources. The common phenomenon behind these mouthpart types is a complex composed of several consecutive mouthparts which structurally interact during food uptake. The single mouthparts are thus only functional in conjunction with other adjacent mouthparts, which is fundamentally different to biting-chewing. It is, however, unclear when structural mouthpart interaction (SMI) evolved since this principle obviously occurred multiple times independently in several extant and extinct winged insect groups. Here, we report a new type of SMI in two of the earliest wingless hexapod lineages--Diplura and Collembola. We found that the mandible and maxilla interact with each other via an articulatory stud at the dorsal side of the maxillary stipes, and they are furthermore supported by structures of the hypopharynx and head capsule. These interactions are crucial stabilizing elements during food uptake. The presence of SMI in these ancestrally wingless insects, and its absence in those crustacean groups probably ancestral to insects, indicates that SMI is a groundplan apomorphy of insects. Our results thus contradict the currently established view of insect mouthpart evolution that biting-chewing mouthparts without any form of SMI are the ancestral configuration. Furthermore, SMIs occur in the earliest insects in a high anatomical variety. SMIs in stemgroup representatives of insects may have triggered efficient exploitation and fast adaptation to new terrestrial food sources much earlier than previously supposed. PMID:26203002

  19. High assurance SPIRAL

    NASA Astrophysics Data System (ADS)

    Franchetti, Franz; Sandryhaila, Aliaksei; Johnson, Jeremy R.

    2014-06-01

    In this paper we introduce High Assurance SPIRAL to solve the last mile problem for the synthesis of high assurance implementations of controllers for vehicular systems that are executed in today's and future embedded and high performance embedded system processors. High Assurance SPIRAL is a scalable methodology to translate a high level specification of a high assurance controller into a highly resource-efficient, platform-adapted, verified control software implementation for a given platform in a language like C or C++. High Assurance SPIRAL proves that the implementation is equivalent to the specification written in the control engineer's domain language. Our approach scales to problems involving floating-point calculations and provides highly optimized synthesized code. It is possible to estimate the available headroom to enable assurance/performance trade-offs under real-time constraints, and enables the synthesis of multiple implementation variants to make attacks harder. At the core of High Assurance SPIRAL is the Hybrid Control Operator Language (HCOL) that leverages advanced mathematical constructs expressing the controller specification to provide high quality translation capabilities. Combined with a verified/certified compiler, High Assurance SPIRAL provides a comprehensive complete solution to the efficient synthesis of verifiable high assurance controllers. We demonstrate High Assurance SPIRALs capability by co-synthesizing proofs and implementations for attack detection and sensor spoofing algorithms and deploy the code as ROS nodes on the Landshark unmanned ground vehicle and on a Synthetic Car in a real-time simulator.

  20. High-Altitude Illness

    MedlinePlus

    ... altitude illness: Acute mountain sickness High-altitude pulmonary edema (also called HAPE), which affects the lungs High-altitude cerebral edema (also called HACE), which affects the brain These ...

  1. High blood pressure

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/000468.htm High blood pressure To use the sharing features on ... body. Hypertension is the term used to describe high blood pressure. Blood pressure readings are given as ...

  2. High Speed data acquisition

    SciTech Connect

    Cooper, Peter S.

    1998-02-01

    A general introduction to high Speed data acquisition system techniques in modern particle physics experiments is given. Examples are drawn from the SELEX(E781) high statistics charmed baryon production and decay experiment now taking data at Fermilab.

  3. High potassium level

    MedlinePlus

    High potassium level is a problem in which the amount of potassium in the blood is higher than normal. The medical ... There are often no symptoms with a high level of potassium. When symptoms do occur, they may ...

  4. Cleaning Up High.

    ERIC Educational Resources Information Center

    Rittner-Heir, Robbin M.

    2001-01-01

    Discusses cleaning techniques and equipment for areas in a school that are hard to reach, such as the high spacious ceilings, the tall windows of a school atrium, and high points in gymnasiums and auditoriums. (GR)

  5. High blood pressure - infants

    MedlinePlus

    Hypertension - infants ... and blood vessels The health of the kidneys High blood pressure in infants may be due to kidney or ... Bronchopulmonary dysplasia Renal artery stenosis In newborn babies, high blood pressure is often caused by a blood clot in ...

  6. High energy neutron radiography

    SciTech Connect

    Gavron, A.; Morley, K.; Morris, C.; Seestrom, S.; Ullmann, J.; Yates, G.; Zumbro, J.

    1996-06-01

    High-energy spallation neutron sources are now being considered in the US and elsewhere as a replacement for neutron beams produced by reactors. High-energy and high intensity neutron beams, produced by unmoderated spallation sources, open potential new vistas of neutron radiography. The authors discuss the basic advantages and disadvantages of high-energy neutron radiography, and consider some experimental results obtained at the Weapons Neutron Research (WNR) facility at Los Alamos.

  7. Tunable high pressure lasers

    NASA Technical Reports Server (NTRS)

    Hess, R. V.

    1976-01-01

    Atmospheric transmission of high energy CO2 lasers is considerably improved by high pressure operation which, due to pressure broadening, permits tuning the laser lines off atmospheric absorption lines. Pronounced improvement is shown for horizontal transmission at altitudes above several kilometers and for vertical transmission through the entire atmosphere. Applications of tunable high pressure CO2 lasers to energy transmission and to remote sensing are discussed along with initial efforts in tuning high pressure CO2 lasers.

  8. High power microwave generator

    DOEpatents

    Ekdahl, C.A.

    1983-12-29

    A microwave generator efficiently converts the energy of an intense relativistic electron beam (REB) into a high-power microwave emission using the Smith-Purcell effect which is related to Cerenkov radiation. Feedback for efficient beam bunching and high gain is obtained by placing a cylindrical Smith-Purcell transmission grating on the axis of a toroidal resonator. High efficiency results from the use of a thin cold annular highly-magnetized REB that is closely coupled to the resonant structure.

  9. High power microwave generator

    DOEpatents

    Ekdahl, Carl A.

    1986-01-01

    A microwave generator efficiently converts the energy of an intense relativistic electron beam (REB) into a high-power microwave emission using the Smith-Purcell effect which is related to Cerenkov radiation. Feedback for efficient beam bunching and high gain is obtained by placing a cylindrical Smith-Purcell transmission grating on the axis of a toroidal resonator. High efficiency results from the use of a thin cold annular highly-magnetized REB that is closely coupled to the resonant structure.

  10. High performance systems

    SciTech Connect

    Vigil, M.B.

    1995-03-01

    This document provides a written compilation of the presentations and viewgraphs from the 1994 Conference on High Speed Computing given at the High Speed Computing Conference, {open_quotes}High Performance Systems,{close_quotes} held at Gleneden Beach, Oregon, on April 18 through 21, 1994.

  11. High speed civil transport

    NASA Technical Reports Server (NTRS)

    Mcknight, R. L.

    1992-01-01

    The design requirements of the High Speed Civil Transport (HSCT) are discussed. The following design concerns are presented: (1) environmental impact (emissions and noise); (2) critical components (the high temperature combustor and the lightweight exhaust nozzle); and (3) advanced materials (high temperature ceramic matrix composites (CMC's)/intermetallic matrix composites (IMC's)/metal matrix composites (MMC's)).

  12. High Technology Partnership Project.

    ERIC Educational Resources Information Center

    Francis Tuttle Vo-Tech Center, Oklahoma City, OK.

    The High Technology Center at Francis Tuttle Vo-Tech Center in Oklahoma City conducted an 18-month demonstration program, beginning in January 1989, to train or retrain average workers, unemployed because of cutbacks in their field or lack of marketable skills, for careers in high technology. The High Technology Center offered adults training in…

  13. High Technology Needs Assessment.

    ERIC Educational Resources Information Center

    Southeastern Louisiana Univ., Hammond.

    A project produced a high technology status report providing needs assessment data for educational planning. The purpose was to determine the impact and future of high technology in Louisiana. Information was obtained from 68 Louisiana manufacturing industries by mailed questionnaire. Data indicated that 45 industries were involved in high tech. A…

  14. Early College High Schools

    ERIC Educational Resources Information Center

    Dessoff, Alan

    2011-01-01

    For at-risk students who stand little chance of going to college, or even finishing high school, a growing number of districts have found a solution: Give them an early start in college while they still are in high school. The early college high school (ECHS) movement that began with funding from the Bill and Melinda Gates Foundation 10 years ago…

  15. Evaluating High School IT

    ERIC Educational Resources Information Center

    Thompson, Brett A.

    2004-01-01

    Since its inception in 1997, Cisco's curriculum has entered thousands of high schools across the U.S. and around the world for two reasons: (1) Cisco has a large portion of the computer networking market, and thus has the resources for and interest in developing high school academies; and (2) high school curriculum development teams recognize the…

  16. High Tech High: Cruising on the Internet.

    ERIC Educational Resources Information Center

    Wilson, Thomas F.

    1995-01-01

    A "driver's license" at one suburban Minnesota high school is a free round-trip ticket to the world. The Internet allows students to stroll through the Louvre, tour the White House, or examine current satellite weather photos at NASA's computer center. Students are developing friendships, exploring different cultures, and learning foreign…

  17. High power, high beam quality regenerative amplifier

    DOEpatents

    Hackel, Lloyd A.; Dane, Clifford B.

    1993-01-01

    A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

  18. High power, high beam quality regenerative amplifier

    DOEpatents

    Hackel, L.A.; Dane, C.B.

    1993-08-24

    A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

  19. High performance polymer development

    NASA Technical Reports Server (NTRS)

    Hergenrother, Paul M.

    1991-01-01

    The term high performance as applied to polymers is generally associated with polymers that operate at high temperatures. High performance is used to describe polymers that perform at temperatures of 177 C or higher. In addition to temperature, other factors obviously influence the performance of polymers such as thermal cycling, stress level, and environmental effects. Some recent developments at NASA Langley in polyimides, poly(arylene ethers), and acetylenic terminated materials are discussed. The high performance/high temperature polymers discussed are representative of the type of work underway at NASA Langley Research Center. Further improvement in these materials as well as the development of new polymers will provide technology to help meet NASA future needs in high performance/high temperature applications. In addition, because of the combination of properties offered by many of these polymers, they should find use in many other applications.

  20. High modulus high temperature glass fibers

    NASA Technical Reports Server (NTRS)

    Bacon, J. F.

    1973-01-01

    The search for a new high-modulus, high-temperature glass fiber involved the preparation of 500 glass compositions lying in 12 glass fields. These systems consisted primarily of low atomic number oxides and rare-earth oxides. Direct optical measurements of the kinetics of crystallization of the cordierite-rare earth system, for example, showed that the addition of rare-earth oxides decreased the rate of formation of cordierite crystals. Glass samples prepared from these systems proved that the rare-earth oxides made large specific contributions to the Young's modulus of the glasses. The best glasses have moduli greater than 21 million psi, the best glass fibers have moduli greater than 18 million psi, and the best glass fiber-epoxy resin composites have tensile strengths of 298,000 psi, compressive strengths of at least 220,000 psi, flexural strengths of 290,000 psi, and short-beam shear strengths of almost 17,000 psi.

  1. High pressure and high temperature apparatus

    DOEpatents

    Voronov, Oleg A.

    2005-09-13

    A design for high pressure/high temperature apparatus and reaction cell to achieve .about.30 GPa pressure in .about.1 cm volume and .about.100 GPa pressure in .about.1 mm volumes and 20-5000.degree. C. temperatures in a static regime. The device includes profiled anvils (28) action on a reaction cell (14, 16) containing the material (26) to be processed. The reaction cell includes a heater (18) surrounded by insulating layers and screens. Surrounding the anvils are cylindrical inserts and supporting rings (30-48) whose hardness increases towards the reaction cell. These volumes may be increased considerably if applications require it, making use of presses that have larger loading force capability, larger frames and using larger anvils.

  2. High Resolution, High Frame Rate Video Technology

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Papers and working group summaries presented at the High Resolution, High Frame Rate Video (HHV) Workshop are compiled. HHV system is intended for future use on the Space Shuttle and Space Station Freedom. The Workshop was held for the dual purpose of: (1) allowing potential scientific users to assess the utility of the proposed system for monitoring microgravity science experiments; and (2) letting technical experts from industry recommend improvements to the proposed near-term HHV system. The following topics are covered: (1) State of the art in the video system performance; (2) Development plan for the HHV system; (3) Advanced technology for image gathering, coding, and processing; (4) Data compression applied to HHV; (5) Data transmission networks; and (6) Results of the users' requirements survey conducted by NASA.

  3. A simple, high efficiency, high resolution spectropolarimeter

    NASA Astrophysics Data System (ADS)

    Barden, Samuel C.

    2012-09-01

    A simple concept is described that uses volume phase holographic gratings as polarizing dispersers for a high efficiency, high resolution spectropolarimeter. Although the idea has previously been mentioned in the literature as possible, such a concept has not been explored in detail. Performance analysis is presented for a VPHG spectropolarimeter concept that could be utilized for both solar and night-time astronomy. Instrumental peak efficiency can approach 100% with spectral dispersions permitting R~200,000 spectral resolution with diffraction limited telescopes. The instrument has 3-channels: two dispersed image planes with orthogonal polarization and an undispersed image plane. The concept has a range of versatility where it could be configured (with appropriate half-wave plates) for slit-fed spectroscopy or without slits for snapshot/hyperspectral/tomographic spectroscopic imaging. Multiplex gratings could also be used for the simultaneous recording of two separate spectral bands or multiple instruments could be daisy chained with beam splitters for further spectral coverage.

  4. HIGH VOLTAGE, HIGH CURRENT SPARK GAP SWITCH

    DOEpatents

    Dike, R.S.; Lier, D.W.; Schofield, A.E.; Tuck, J.L.

    1962-04-17

    A high voltage and current spark gap switch comprising two main electrodes insulatingly supported in opposed spaced relationship and a middle electrode supported medially between the main electrodes and symmetrically about the median line of the main electrodes is described. The middle electrode has a perforation aligned with the median line and an irradiation electrode insulatingly supported in the body of the middle electrode normal to the median line and protruding into the perforation. (AEC)

  5. High energy high brightness thin disk laser

    NASA Astrophysics Data System (ADS)

    Nixon, Matthew D.; Cates, Michael C.

    2012-11-01

    Boeing has been developing solid state lasers for high energy applications since 2004 using Yb:YAG thin disk lasers as pioneered by A. Giesen1 and commercialized by Trumpf Laser GmbH.2 In this paper, we report results of our second generation design and status of a third generation we are currently developing, which will produce 35 kW and a beam quality <2.

  6. High frequency, high power capacitor development

    NASA Technical Reports Server (NTRS)

    White, C. W.; Hoffman, P. S.

    1983-01-01

    A program to develop a special high energy density, high power transfer capacitor to operate at frequency of 40 kHz, 600 V rms at 125 A rms plus 600 V dc bias for space operation. The program included material evaluation and selection, a capacitor design was prepared, a thermal analysis performed on the design. Fifty capacitors were manufactured for testing at 10 kHz and 40 kHz for 50 hours at Industrial Electric Heating Co. of Columbus, Ohio. The vacuum endurance test used on environmental chamber and temperature plate furnished by Maxwell. The capacitors were energized with a special power conditioning apparatus developed by Industrial Electric Heating Co. Temperature conditions of the capacitors were monitored by IEHCo test equipment. Successful completion of the vacuum endurance test series confirmed achievement of the main goal of producing a capacitor or reliable operation at high frequency in an environment normally not hospitable to electrical and electronic components. The capacitor developed compared to a typical commercial capacitor at the 40 kHz level represents a decrease in size and weight by a factor of seven.

  7. High output lamp with high brightness

    DOEpatents

    Kirkpatrick, Douglas A.; Bass, Gary K.; Copsey, Jesse F.; Garber, Jr., William E.; Kwong, Vincent H.; Levin, Izrail; MacLennan, Donald A.; Roy, Robert J.; Steiner, Paul E.; Tsai, Peter; Turner, Brian P.

    2002-01-01

    An ultra bright, low wattage inductively coupled electrodeless aperture lamp is powered by a solid state RF source in the range of several tens to several hundreds of watts at various frequencies in the range of 400 to 900 MHz. Numerous novel lamp circuits and components are disclosed including a wedding ring shaped coil having one axial and one radial lead, a high accuracy capacitor stack, a high thermal conductivity aperture cup and various other aperture bulb configurations, a coaxial capacitor arrangement, and an integrated coil and capacitor assembly. Numerous novel RF circuits are also disclosed including a high power oscillator circuit with reduced complexity resonant pole configuration, parallel RF power FET transistors with soft gate switching, a continuously variable frequency tuning circuit, a six port directional coupler, an impedance switching RF source, and an RF source with controlled frequency-load characteristics. Numerous novel RF control methods are disclosed including controlled adjustment of the operating frequency to find a resonant frequency and reduce reflected RF power, controlled switching of an impedance switched lamp system, active power control and active gate bias control.

  8. High speed handpieces

    PubMed Central

    Bhandary, Nayan; Desai, Asavari; Shetty, Y Bharath

    2014-01-01

    High speed instruments are versatile instruments used by clinicians of all specialties of dentistry. It is important for clinicians to understand the types of high speed handpieces available and the mechanism of working. The centers for disease control and prevention have issued guidelines time and again for disinfection and sterilization of high speed handpieces. This article presents the recent developments in the design of the high speed handpieces. With a view to prevent hospital associated infections significant importance has been given to disinfection, sterilization & maintenance of high speed handpieces. How to cite the article: Bhandary N, Desai A, Shetty YB. High speed handpieces. J Int Oral Health 2014;6(1):130-2. PMID:24653618

  9. Highly directional thermal emitter

    DOEpatents

    Ribaudo, Troy; Shaner, Eric A; Davids, Paul; Peters, David W

    2015-03-24

    A highly directional thermal emitter device comprises a two-dimensional periodic array of heavily doped semiconductor structures on a surface of a substrate. The array provides a highly directional thermal emission at a peak wavelength between 3 and 15 microns when the array is heated. For example, highly doped silicon (HDSi) with a plasma frequency in the mid-wave infrared was used to fabricate nearly perfect absorbing two-dimensional gratings structures that function as highly directional thermal radiators. The absorption and emission characteristics of the HDSi devices possessed a high degree of angular dependence for infrared absorption in the 10-12 micron range, while maintaining high reflectivity of solar radiation (.about.64%) at large incidence angles.

  10. High lift selected concepts

    NASA Technical Reports Server (NTRS)

    Henderson, M. L.

    1979-01-01

    The benefits to high lift system maximum life and, alternatively, to high lift system complexity, of applying analytic design and analysis techniques to the design of high lift sections for flight conditions were determined and two high lift sections were designed to flight conditions. The influence of the high lift section on the sizing and economics of a specific energy efficient transport (EET) was clarified using a computerized sizing technique and an existing advanced airplane design data base. The impact of the best design resulting from the design applications studies on EET sizing and economics were evaluated. Flap technology trade studies, climb and descent studies, and augmented stability studies are included along with a description of the baseline high lift system geometry, a calculation of lift and pitching moment when separation is present, and an inverse boundary layer technique for pressure distribution synthesis and optimization.

  11. High-altitude headache.

    PubMed

    Marmura, Michael J; Hernandez, Pablo Bandres

    2015-05-01

    High-altitude headache is one of many neurological symptoms associated with the ascent to high altitudes. Cellular hypoxia due to decreased barometric pressure seems to be the common final pathway for headache as altitude increases. Susceptibility to high-altitude headache depends on genetic factors, history of migraine, and acclimatization, but symptoms of acute mountain sickness are universal at very high altitudes. This review summarizes the pathophysiology of acute mountain sickness and high-altitude headache as well as the evidence for treatment and prevention with different drugs and devices which may be useful for regular and novice mountaineers. This includes an examination of other headache disorders which may mimic high-altitude headache. PMID:25795155

  12. High-Temperature Superconductivity

    NASA Astrophysics Data System (ADS)

    Tanaka, Shoji

    2006-12-01

    A general review on high-temperature superconductivity was made. After prehistoric view and the process of discovery were stated, the special features of high-temperature superconductors were explained from the materials side and the physical properties side. The present status on applications of high-temperature superconductors were explained on superconducting tapes, electric power cables, magnets for maglev trains, electric motors, superconducting quantum interference device (SQUID) and single flux quantum (SFQ) devices and circuits.

  13. High redshift GRBs

    NASA Astrophysics Data System (ADS)

    Gehrels, Neil; Cannizzo, John K.

    2012-09-01

    The Swift mission has opened a new, high redshift window on the universe. In this review we provide an overview of gamma-ray burst (GRB) science, describe the Swift mission, discuss high-z GRBs and tools for high-z studies, and look forward at future capabilities. A new mission concept - Lobster - is described that would monitor the X-ray sky at order of magnitude higher sensitivity than current missions.

  14. High Redshift GRBs

    NASA Technical Reports Server (NTRS)

    Gehrels, Neil; Cannizzo, John K.

    2012-01-01

    The Swift mission has opened a new, high redshift window on the universe. In this review we provide an overview of gamma-ray burst (GRB) science, describe the Swift mission, discuss high-z GRBs and tools for high-z studies, and look forward at future capabilities. A new mission concept - Lobster - is described that would monitor the X-ray sky at order of magnitude higher sensitivity than current missions.

  15. High temperature furnace

    DOEpatents

    Borkowski, Casimer J.

    1976-08-03

    A high temperature furnace for use above 2000.degree.C is provided that features fast initial heating and low power consumption at the operating temperature. The cathode is initially heated by joule heating followed by electron emission heating at the operating temperature. The cathode is designed for routine large temperature excursions without being subjected to high thermal stresses. A further characteristic of the device is the elimination of any ceramic components from the high temperature zone of the furnace.

  16. High temperature refrigerator

    DOEpatents

    Steyert, Jr., William A.

    1978-01-01

    A high temperature magnetic refrigerator which uses a Stirling-like cycle in which rotating magnetic working material is heated in zero field and adiabatically magnetized, cooled in high field, then adiabatically demagnetized. During this cycle said working material is in heat exchange with a pumped fluid which absorbs heat from a low temperature heat source and deposits heat in a high temperature reservoir. The magnetic refrigeration cycle operates at an efficiency 70% of Carnot.

  17. High Reynolds Number Research

    NASA Technical Reports Server (NTRS)

    Baals, D. D. (Editor)

    1977-01-01

    Fundamental aerodynamic questions for which high Reynolds number experimental capability is required are discussed. The operational characteristics and design features of the National Transonic Facility are reviewed.

  18. High altitude decelerator systems

    NASA Technical Reports Server (NTRS)

    Silbert, Mendel N.; Moltedo, A. David; Gilbertson, Gaylord S.

    1989-01-01

    High Altitude Decelerator Systems are used to provide a stable descending platform when deployed from a sounding rocket at altitudes greater than 40 kilometers allowing a scientific mission to be conducted in a specific altitude region. The High Altitude Decelerator is designed to provide a highly stable, high drag area system packed in a minimum volume to deploy successfully from a sounding rocket. Deployment altitudes greater than 100 kilometers have been successfully demonstrated at dynamic pressures as low as 0.004 pounds per square foot.

  19. High power, high frequency helix TWT's

    NASA Astrophysics Data System (ADS)

    Sloley, H. J.; Willard, J.; Paatz, S. R.; Keat, M. J.

    The design and performance characteristics of a 34-GHz pulse tube capable of 75 W peak power output at 30 percent duty cycle and a broadband CW tube are presented. Particular attention is given to the engineering problems encountered during the development of the tubes, including the suppression of backward wave oscillation, the design of electron guns for small-diameter high-current beams, and the thermal capability of small helix structures. The discussion also covers the effects of various design parameters and choice of engineering materials on the ultimate practical limit of power and gain at the operating frequencies. Measurements are presented for advanced experimental tubes.

  20. High power, high frequency, vacuum flange

    DOEpatents

    Felker, B.; McDaniel, M.R.

    1993-03-23

    An improved waveguide flange is disclosed for high power operation that helps prevent arcs from being initiated at the junctions between waveguide sections. The flanges at the end of the waveguide sections have counter bores surrounding the waveguide tubes. When the sections are bolted together the counter bores form a groove that holds a fully annealed copper gasket. Each counterbore has a beveled step that is specially configured to insure the gasket forms a metal-to-metal vacuum seal without gaps or sharp edges. The resultant inner surface of the waveguide is smooth across the junctions between waveguide sections, and arcing is prevented.

  1. High power, high frequency, vacuum flange

    DOEpatents

    Felker, Brian; McDaniel, Michael R.

    1993-01-01

    An improved waveguide flange is disclosed for high power operation that helps prevent arcs from being initiated at the junctions between waveguide sections. The flanges at the end of the waveguide sections have counterbores surrounding the waveguide tubes. When the sections are bolted together the counterbores form a groove that holds a fully annealed copper gasket. Each counterbore has a beveled step that is specially configured to insure the gasket forms a metal-to-metal vacuum seal without gaps or sharp edges. The resultant inner surface of the waveguide is smooth across the junctions between waveguide sections, and arcing is prevented.

  2. High performance, high density hydrocarbon fuels

    NASA Technical Reports Server (NTRS)

    Frankenfeld, J. W.; Hastings, T. W.; Lieberman, M.; Taylor, W. F.

    1978-01-01

    The fuels were selected from 77 original candidates on the basis of estimated merit index and cost effectiveness. The ten candidates consisted of 3 pure compounds, 4 chemical plant streams and 3 refinery streams. Critical physical and chemical properties of the candidate fuels were measured including heat of combustion, density, and viscosity as a function of temperature, freezing points, vapor pressure, boiling point, thermal stability. The best all around candidate was found to be a chemical plant olefin stream rich in dicyclopentadiene. This material has a high merit index and is available at low cost. Possible problem areas were identified as low temperature flow properties and thermal stability. An economic analysis was carried out to determine the production costs of top candidates. The chemical plant and refinery streams were all less than 44 cent/kg while the pure compounds were greater than 44 cent/kg. A literature survey was conducted on the state of the art of advanced hydrocarbon fuel technology as applied to high energy propellents. Several areas for additional research were identified.

  3. Highly Parallel, High-Precision Numerical Integration

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2005-04-22

    This paper describes a scheme for rapidly computing numerical values of definite integrals to very high accuracy, ranging from ordinary machine precision to hundreds or thousands of digits, even for functions with singularities or infinite derivatives at endpoints. Such a scheme is of interest not only in computational physics and computational chemistry, but also in experimental mathematics, where high-precision numerical values of definite integrals can be used to numerically discover new identities. This paper discusses techniques for a parallel implementation of this scheme, then presents performance results for 1-D and 2-D test suites. Results are also given for a certain problem from mathematical physics, which features a difficult singularity, confirming a conjecture to 20,000 digit accuracy. The performance rate for this latter calculation on 1024 CPUs is 690 Gflop/s. We believe that this and one other 20,000-digit integral evaluation that we report are the highest-precision non-trivial numerical integrations performed to date.

  4. The American High School

    ERIC Educational Resources Information Center

    Ediger, Marlow

    2008-01-01

    Of all levels of schooling, the high school receives by far the most criticism. There are continuous innovations recommended in journal articles, textbooks, and speeches at state/national conventions on ways to improve the secondary level of schooling. At one teacher education convention, the speaker was criticizing the American high school and…

  5. High-Stakes Testing.

    ERIC Educational Resources Information Center

    Nieto, Sonia; Irizarry, Jason G.; Luna, Cathy

    2002-01-01

    Discusses four books that provide critical information about the nature of high-stakes tests; the impact of these tests on teaching, learning, and students; the political issues surrounding high-stakes testing; and ways that educators can take informed action to appropriately respond to these tests. (SG)

  6. High School Gifted.

    ERIC Educational Resources Information Center

    Drum, Jean, Ed.

    1993-01-01

    This theme issue on gifted high school students presents several feature articles, a California legislative update, and an editorial. In "Summer Seminar '93--California in the 21st Century," Janis Van Dreal describes a 2-week residential program in which gifted high school students examined California's future. "Visiting a Gifted Program in…

  7. High School Oceanography.

    ERIC Educational Resources Information Center

    Falmouth Public Schools, MA.

    This book is a compilation of a series of papers designed to aid high school teachers in organizing a course in oceanography for high school students. It consists of twelve papers, with references, covering each of the following: (1) Introduction to Oceanography, (2) Geology of the Ocean, (3) The Continental Shelves, (4) Physical Properties of Sea…

  8. High Blood Pressure (Hypertension)

    MedlinePlus

    ... For Consumers Consumer Information by Audience For Women High Blood Pressure (Hypertension) Share Tweet Linkedin Pin it More sharing options ... En Español Who is at risk? How is high blood pressure treated? Understanding your blood pressure: What do the ...

  9. High-Conflict Divorce.

    ERIC Educational Resources Information Center

    Johnston, Janet R.

    1994-01-01

    Reviews available research studies of high-conflict divorce and its effects on children. Factors believed to contribute to high-conflict divorce are explored, and a model of their interrelationships is proposed. Dispute resolution, intervention, and prevention programs are discussed, and implications for social policy are outlined. (SLD)

  10. High Involvement Work Teams.

    ERIC Educational Resources Information Center

    1996

    These three papers were presented at a symposium on high-involvement work teams moderated by Michael Leimbach at the 1996 conference of the Academy of Human Resource Development. "Beyond Training to the New Learning Environment: Workers on the High-Involvement Frontline" (Joseph Anthony Ilacqua, Carol Ann Zulauf) shows the link between an…

  11. High School Chemistry.

    ERIC Educational Resources Information Center

    Journal of Chemical Education, 1983

    1983-01-01

    Preparation for college or life, working conditions and continuing education for high school chemistry teachers, and form/function of high school chemistry textbooks were addressed in presentations at the Seventh Biennial Conference on Chemical Education (Stillwater, Oklahoma 1982). Workshops, lectures, and demonstrations were also presented to…

  12. High Speed data acquisition

    SciTech Connect

    Cooper, P.S.

    1998-02-01

    A general introduction to high Speed data acquisition system techniques in modern particle physics experiments is given. Examples are drawn from the SELEX(E781) high statistics charmed baryon production and decay experiment now taking data at Fermilab. {copyright} {ital 1998 American Institute of Physics.}

  13. High temperature sensor

    DOEpatents

    Tokarz, Richard D.

    1982-01-01

    A high temperature sensor includes a pair of electrical conductors separated by a mass of electrical insulating material. The insulating material has a measurable resistivity within the sensor that changes in relation to the temperature of the insulating material within a high temperature range (1,000 to 2,000 K.). When required, the sensor can be encased within a ceramic protective coating.

  14. High coking value pitch

    DOEpatents

    Miller, Douglas J.; Chang, Ching-Feng; Lewis, Irwin C.; Lewis, Richard T.

    2014-06-10

    A high coking value pitch prepared from coal tar distillate and has a low softening point and a high carbon value while containing substantially no quinoline insolubles is disclosed. The pitch can be used as an impregnant or binder for producing carbon and graphite articles.

  15. High School Programming.

    ERIC Educational Resources Information Center

    Update on Gifted Education, 1992

    1992-01-01

    This theme issue covers "High School Programming" and approaches to meeting the needs of gifted high school students in Texas. The first article is "Thematic Interdisciplinary Curricula for Secondary Gifted Students in English and Social Studies" (Joel E. McIntosh and April W. Meacham). This approach is contrasted with the traditional curriculum…

  16. High energy forming facility

    NASA Technical Reports Server (NTRS)

    Ciurlionis, B.

    1967-01-01

    Watertight, high-explosive forming facility, 25 feet in diameter and 15 feet deep, withstands repeated explosions of 10 pounds of TNT equivalent. The shell is fabricated of high strength steel and allows various structural elements to deform or move elastically and independently while retaining structural integrity.

  17. High School: Erasing Borders

    ERIC Educational Resources Information Center

    Wright, Dianne; Bogotch, Ira

    2006-01-01

    Over the last several years there have been numerous calls for reforming high school to college transitions. In 2000-2001, the American Youth Policy Forum (AYPF) and the National Commission on the High School Senior Year respectively called for a re-thinking of how students moved from secondary to postsecondary education. A widely-discussed…

  18. Reforming Underperforming High Schools

    ERIC Educational Resources Information Center

    MDRC, 2013

    2013-01-01

    Urban high schools are in trouble--high dropout rates, low student academic achievement, and graduates who are unprepared for college are just some of the disappointing indicators. However, recent research points to a select number of approaches to improving student outcomes and reforming underperforming schools--from particular ways of creating…

  19. High and Dry

    ERIC Educational Resources Information Center

    Johnson, Robert L.

    2005-01-01

    High-performance schools are facilities that improve the learning environment while saving energy, resources and money. Creating a high-performance school requires an integrated design approach. Key systems--including lighting, HVAC, electrical and plumbing--must be considered from the beginning of the design process. According to William H.…

  20. High current high accuracy IGBT pulse generator

    SciTech Connect

    Nesterov, V.V.; Donaldson, A.R.

    1995-05-01

    A solid state pulse generator capable of delivering high current triangular or trapezoidal pulses into an inductive load has been developed at SLAC. Energy stored in a capacitor bank of the pulse generator is switched to the load through a pair of insulated gate bipolar transistors (IGBT). The circuit can then recover the remaining energy and transfer it back to the capacitor bank without reversing the capacitor voltage. A third IGBT device is employed to control the initial charge to the capacitor bank, a command charging technique, and to compensate for pulse to pulse power losses. The rack mounted pulse generator contains a 525 {mu}F capacitor bank. It can deliver 500 A at 900V into inductive loads up to 3 mH. The current amplitude and discharge time are controlled to 0.02% accuracy by a precision controller through the SLAC central computer system. This pulse generator drives a series pair of extraction dipoles.

  1. High redshift quasars and high metallicities

    NASA Technical Reports Server (NTRS)

    Ferland, Gary J.

    1997-01-01

    A large-scale code called Cloudy was designed to simulate non-equilibrium plasmas and predict their spectra. The goal was to apply it to studies of galactic and extragalactic emission line objects in order to reliably deduce abundances and luminosities. Quasars are of particular interest because they are the most luminous objects in the universe and the highest redshift objects that can be observed spectroscopically, and their emission lines can reveal the composition of the interstellar medium (ISM) of the universe when it was well under a billion years old. The lines are produced by warm (approximately 10(sup 4)K) gas with moderate to low density (n less than or equal to 10(sup 12) cm(sup -3)). Cloudy has been extended to include approximately 10(sup 4) resonance lines from the 495 possible stages of ionization of the lightest 30 elements, an extension that required several steps. The charge transfer database was expanded to complete the needed reactions between hydrogen and the first four ions and fit all reactions with a common approximation. Radiative recombination rate coefficients were derived for recombination from all closed shells, where this process should dominate. Analytical fits to Opacity Project (OP) and other recent photoionization cross sections were produced. Finally, rescaled OP oscillator strengths were used to compile a complete set of data for 5971 resonance lines. The major discovery has been that high redshift quasars have very high metallicities and there is strong evidence that the quasar phenomenon is associated with the birth of massive elliptical galaxies.

  2. High-pressure microfluidics

    NASA Astrophysics Data System (ADS)

    Hjort, K.

    2015-03-01

    When using appropriate materials and microfabrication techniques, with the small dimensions the mechanical stability of microstructured devices allows for processes at high pressures without loss in safety. The largest area of applications has been demonstrated in green chemistry and bioprocesses, where extraction, synthesis and analyses often excel at high densities and high temperatures. This is accessible through high pressures. Capillary chemistry has been used since long but, just like in low-pressure applications, there are several potential advantages in using microfluidic platforms, e.g., planar isothermal set-ups, large local variations in geometries, dense form factors, small dead volumes and precisely positioned microstructures for control of reactions, catalysis, mixing and separation. Other potential applications are in, e.g., microhydraulics, exploration, gas driven vehicles, and high-pressure science. From a review of the state-of-art and frontiers of high pressure microfluidics, the focus will be on different solutions demonstrated for microfluidic handling at high pressures and challenges that remain.

  3. High Power Hall Thrusters

    NASA Technical Reports Server (NTRS)

    Jankovsky, Robert; Tverdokhlebov, Sergery; Manzella, David

    1999-01-01

    The development of Hall thrusters with powers ranging from tens of kilowatts to in excess of one hundred kilowatts is considered based on renewed interest in high power. high thrust electric propulsion applications. An approach to develop such thrusters based on previous experience is discussed. It is shown that the previous experimental data taken with thrusters of 10 kW input power and less can be used. Potential mass savings due to the design of high power Hall thrusters are discussed. Both xenon and alternate thruster propellant are considered, as are technological issues that will challenge the design of high power Hall thrusters. Finally, the implications of such a development effort with regard to ground testing and spacecraft intecrati'on issues are discussed.

  4. High-mix insulins

    PubMed Central

    Kalra, Sanjay; Farooqi, Mohammad Hamed; El-Houni, Ali E.

    2015-01-01

    Premix insulins are commonly used insulin preparations, which are available in varying ratios of different molecules. These drugs contain one short- or rapid-acting, and one intermediate- or long-acting insulin. High-mix insulins are mixtures of insulins that contain 50% or more than 50% of short-acting insulin. This review describes the clinical pharmacology of high-mix insulins, including data from randomized controlled trials. It suggests various ways, in which high-mix insulin can be used, including once daily, twice daily, thrice daily, hetero-mix, and reverse regimes. The authors provide a rational framework to help diabetes care professionals, identify indications for pragmatic high-mix use. PMID:26425485

  5. Hypertension (High Blood Pressure)

    MedlinePlus

    ... pressure to live. Without it, blood can't flow through our bodies and carry oxygen to our vital organs. But when blood pressure gets too high — a condition called hypertension — it can lead to ...

  6. Diamond Ranch High School.

    ERIC Educational Resources Information Center

    Betsky, Aaron

    2000-01-01

    Highlights award-winning Diamond Ranch High School (California) that was designed and built on a steep site around Los Angeles considered unsatisfactory for building due to its unstable soils. Building organization is discussed, and photos are provided. (GR)

  7. High pressure furnace

    DOEpatents

    Morris, D.E.

    1993-09-14

    A high temperature high pressure furnace has a hybrid partially externally heated construction. A metallic vessel fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum)). The disclosed alloy is fabricated into 11/4 or 2 inch, 32 mm or 50 mm bar stock and has a length of about 22 inches, 56 cm. This bar stock has an aperture formed therein to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the vessel is provided with a small blind aperture into which a thermocouple can be inserted. The closed end of the vessel is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior. 19 figures.

  8. High pressure furnace

    DOEpatents

    Morris, Donald E.

    1993-01-01

    A high temperature high pressure furnace has a hybrid partially externally heated construction. A metallic vessel fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 or 2 inch, 32 mm or 50 mm bar stock and has a length of about 22 inches, 56 cm. This bar stock has an aperture formed therein to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the vessel is provided with a small blind aperture into which a thermocouple can be inserted. The closed end of the vessel is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior.

  9. High blood pressure medicines

    MedlinePlus

    Hypertension - medicines ... blood vessel diseases. You may need to take medicines to lower your blood pressure if lifestyle changes ... blood pressure to the target level. WHEN ARE MEDICINES FOR HIGH BLOOD PRESSURE USED Most of the ...

  10. High-Temperature Lubricants

    NASA Technical Reports Server (NTRS)

    1984-01-01

    In the early 1980's, Lewis Research Center began a program to develop high-temperature lubricants for use on future aircraft flying at three or more times the speed of sound, which can result in vehicle skin temperatures as high as 1,600 degrees Fahrenheit. A material that emerged from this research is a plasma-sprayed, self-lubricating metal- glass-fluoride coating able to reduce oxidation at very high temperatures. Technology is now in commercial use under the trade name Surf-Kote C-800, marketed by Hohman Plating and Manufacturing Inc. and manufactured under a patent license from NASA. Among its uses are lubrication for sliding contact bearings, shaft seals for turbopumps, piston rings for high performance compressors and hot glass processing machinery; it is also widely used in missile and space applications.

  11. High Redshift Quasars

    NASA Technical Reports Server (NTRS)

    Elvis, Martin S.

    1996-01-01

    The report for this period includes three papers: 'Associated Absorption at Low and High Redshift'; 'Strong X-ray Absorption in a Broad Absorption Line Quasar: PHL5200'; and 'ASCA and ROSAT X-ray Spectra of High-Redshift Radio-Loud Quasars'. The first gives examples from both low and high redshift for combining information on absorbing material in active galactic nuclei from both x-ray and the UV. The second presents ASCA observations of the z = 1.98 prototype broad absorption line quasar (BALQSO): PHL 5200, detected with both the solid-state imaging spectrometers and the gas imaging spectometers. The third paper presents results on the x-ray properties of 9 high-redshift radio-loud quasars observed by ASCA and ROSAT, including ASCA observations of S5 0014+81 (z = 3.38) and S5 0836+71 (z = 2.17) and ROSAT observations of PKS 2126-158.

  12. High-Temperature Superconductivity

    SciTech Connect

    Peter Johnson

    2008-11-05

    Like astronomers tweaking images to gain a more detailed glimpse of distant stars, physicists at Brookhaven National Laboratory have found ways to sharpen images of the energy spectra in high-temperature superconductors — materials that carry electrical c

  13. Highly Autonomous Systems Workshop

    NASA Technical Reports Server (NTRS)

    Doyle, R.; Rasmussen, R.; Man, G.; Patel, K.

    1998-01-01

    It is our aim by launching a series of workshops on the topic of highly autonomous systems to reach out to the larger community interested in technology development for remotely deployed systems, particularly those for exploration.

  14. High-Temperature Superconductivity

    ScienceCinema

    Peter Johnson

    2010-01-08

    Like astronomers tweaking images to gain a more detailed glimpse of distant stars, physicists at Brookhaven National Laboratory have found ways to sharpen images of the energy spectra in high-temperature superconductors ? materials that carry electrical c

  15. High School Parking Lots.

    ERIC Educational Resources Information Center

    Neff, Thomas G.

    2002-01-01

    Describes the reorganization of the site of Ben Davis High School in Wayne Township, Indiana as an example of improvements to school parking lot design and vehicle/pedestrian traffic flow and security. Includes design drawings. (EV)

  16. High blood cholesterol levels

    MedlinePlus

    ... gov/ency/article/000403.htm High blood cholesterol levels To use the sharing features on this page, ... called "bad" cholesterol For many people, abnormal cholesterol levels are partly due to an unhealthy lifestyle. This ...

  17. Hyperglycemia (High Blood Glucose)

    MedlinePlus Videos and Cool Tools

    ... and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High ... prediabetes, and no one is excused. Take the test. Know where you stand. sticky en -- Chef Ronaldo's ...

  18. High pressure oxygen furnace

    DOEpatents

    Morris, Donald E.

    1992-01-01

    A high temperature high pressure oxygen furnace having a hybrid partially externally heated construction is disclosed. A metallic bar fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 inch bar stock and has a length of about 17 inches. This bar stock is gun drilled for over 16 inches of its length with 0.400 inch aperture to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the bar is provided with a small support aperture into which both a support and a thermocouple can be inserted. The closed end of the gun drilled bar is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior.

  19. High pressure oxygen furnace

    DOEpatents

    Morris, D.E.

    1992-07-14

    A high temperature high pressure oxygen furnace having a hybrid partially externally heated construction is disclosed. A metallic bar fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized, the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 inch bar stock and has a length of about 17 inches. This bar stock is gun drilled for over 16 inches of its length with 0.400 inch aperture to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the bar is provided with a small support aperture into which both a support and a thermocouple can be inserted. The closed end of the gun drilled bar is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior. 5 figs.

  20. High Velocity Gas Gun

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A video tape related to orbital debris research is presented. The video tape covers the process of loading a High Velocity Gas Gun and firing it into a mounted metal plate. The process is then repeated in slow motion.

  1. High Speed Research Program

    NASA Technical Reports Server (NTRS)

    Anderson, Robert E.; Corsiglia, Victor R.; Schmitz, Frederic H. (Technical Monitor)

    1994-01-01

    An overview of the NASA High Speed Research Program will be presented from a NASA Headquarters perspective. The presentation will include the objectives of the program and an outline of major programmatic issues.

  2. High Blood Pressure

    MedlinePlus

    ... Division of Geriatrics and Clinical Gerontology Division of Neuroscience FAQs Funding Opportunities Intramural Research Program Office of ... to major health problems. Make a point of learning what blood pressure should be. And, remember: High ...

  3. High Efficiency, High Performance Clothes Dryer

    SciTech Connect

    Peter Pescatore; Phil Carbone

    2005-03-31

    This program covered the development of two separate products; an electric heat pump clothes dryer and a modulating gas dryer. These development efforts were independent of one another and are presented in this report in two separate volumes. Volume 1 details the Heat Pump Dryer Development while Volume 2 details the Modulating Gas Dryer Development. In both product development efforts, the intent was to develop high efficiency, high performance designs that would be attractive to US consumers. Working with Whirlpool Corporation as our commercial partner, TIAX applied this approach of satisfying consumer needs throughout the Product Development Process for both dryer designs. Heat pump clothes dryers have been in existence for years, especially in Europe, but have not been able to penetrate the market. This has been especially true in the US market where no volume production heat pump dryers are available. The issue has typically been around two key areas: cost and performance. Cost is a given in that a heat pump clothes dryer has numerous additional components associated with it. While heat pump dryers have been able to achieve significant energy savings compared to standard electric resistance dryers (over 50% in some cases), designs to date have been hampered by excessively long dry times, a major market driver in the US. The development work done on the heat pump dryer over the course of this program led to a demonstration dryer that delivered the following performance characteristics: (1) 40-50% energy savings on large loads with 35 F lower fabric temperatures and similar dry times; (2) 10-30 F reduction in fabric temperature for delicate loads with up to 50% energy savings and 30-40% time savings; (3) Improved fabric temperature uniformity; and (4) Robust performance across a range of vent restrictions. For the gas dryer development, the concept developed was one of modulating the gas flow to the dryer throughout the dry cycle. Through heat modulation in a

  4. Fulminant high altitude blindness.

    PubMed

    Mashkovskiy, Evgeny; Szawarski, Piotr; Ryzhkov, Pavel; Goslar, Tomaz; Mrak, Irena

    2016-06-01

    Prolonged altitude exposure even with acclimatization continues to present a physiological challenge to all organ systems including the central nervous system. We describe a case of a 41-year-old Caucasian female climber who suffered severe visual loss that was due to possible optic nerve pathology occurring during a high altitude expedition in the Himalayas. This case is atypical of classic high altitude cerebral oedema and highlights yet another danger of prolonged sojourn at extreme altitudes. PMID:27601532

  5. High-temperature electronics

    NASA Technical Reports Server (NTRS)

    Matus, Lawrence G.; Seng, Gary T.

    1990-01-01

    To meet the needs of the aerospace propulsion and space power communities, the high temperature electronics program at the Lewis Research Center is developing silicon carbide (SiC) as a high temperature semiconductor material. This program supports a major element of the Center's mission - to perform basic and developmental research aimed at improving aerospace propulsion systems. Research is focused on developing the crystal growth, characterization, and device fabrication technologies necessary to produce a family of SiC devices.

  6. HIGH TEMPERATURE THERMOCOUPLE

    DOEpatents

    Eshayu, A.M.

    1963-02-12

    This invention contemplates a high temperature thermocouple for use in an inert or a reducing atmosphere. The thermocouple limbs are made of rhenium and graphite and these limbs are connected at their hot ends in compressed removable contact. The rhenium and graphite are of high purity and are substantially stable and free from diffusion into each other even without shielding. Also, the graphite may be thick enough to support the thermocouple in a gas stream. (AEC)

  7. High-temperature sensor

    DOEpatents

    Not Available

    1981-01-29

    A high temperature sensor is described which includes a pair of electrical conductors separated by a mass of electrical insulating material. The insulating material has a measurable resistivity within the sensor that changes in relation to the temperature of the insulating material within a high temperature range (1000 to 2000/sup 0/K). When required, the sensor can be encased within a ceramic protective coating.

  8. High efficiency incandescent lighting

    SciTech Connect

    Bermel, Peter; Ilic, Ognjen; Chan, Walker R.; Musabeyoglu, Ahmet; Cukierman, Aviv Ruben; Harradon, Michael Robert; Celanovic, Ivan; Soljacic, Marin

    2014-09-02

    Incandescent lighting structure. The structure includes a thermal emitter that can, but does not have to, include a first photonic crystal on its surface to tailor thermal emission coupled to, in a high-view-factor geometry, a second photonic filter selected to reflect infrared radiation back to the emitter while passing visible light. This structure is highly efficient as compared to standard incandescent light bulbs.

  9. High conductivity composite metal

    DOEpatents

    Zhou, Ruoyi; Smith, James L.; Embury, John David

    1998-01-01

    Electrical conductors and methods of producing them, where the conductors possess both high strength and high conductivity. Conductors are comprised of carbon steel and a material chosen from a group consisting of copper, nickel, silver, and gold. Diffusion barriers are placed between these two materials. The components of a conductor are assembled and then the assembly is subjected to heat treating and mechanical deformation steps.

  10. High conductivity composite metal

    DOEpatents

    Zhou, R.; Smith, J.L.; Embury, J.D.

    1998-01-06

    Electrical conductors and methods of producing them are disclosed, where the conductors possess both high strength and high conductivity. Conductors are comprised of carbon steel and a material chosen from a group consisting of copper, nickel, silver, and gold. Diffusion barriers are placed between these two materials. The components of a conductor are assembled and then the assembly is subjected to heat treating and mechanical deformation steps. 10 figs.

  11. High pressure gas target

    NASA Astrophysics Data System (ADS)

    Gelbart, W.; Johnson, R. R.; Abeysekera, B.

    2012-12-01

    Compact, high pressure, high current gas target features all metal construction and semi-automatic window assembly change. The unique aspect of this target is the domed-shaped window. The Havar alloy window is electron beam welded to a metal ring, thus forming one, interchangeable assembly. The window assembly is sealed by knife-edges locked by a pneumatic toggle allowing a quick, in situ window change.

  12. High beta multipoles

    SciTech Connect

    Prager, S C

    1982-05-01

    Multipoles are being employed as devices to study fusion issues and plasma phenomena at high values of beta (plasma pressure/magnetic pressure) in a controlled manner. Due to their large volume, low magnetic field (low synchrotron radiation) region, they are also under consideration as potential steady state advanced fuel (low neutron yield) reactors. Present experiments are investigating neoclassical (bootstrap and Pfirsch-Schlueter) currents and plasma stability at extremely high beta.

  13. High temperature pressure gauge

    DOEpatents

    Echtler, J. Paul; Scandrol, Roy O.

    1981-01-01

    A high temperature pressure gauge comprising a pressure gauge positioned in fluid communication with one end of a conduit which has a diaphragm mounted in its other end. The conduit is filled with a low melting metal alloy above the diaphragm for a portion of its length with a high temperature fluid being positioned in the remaining length of the conduit and in the pressure gauge.

  14. High Performance Polymers

    NASA Technical Reports Server (NTRS)

    Venumbaka, Sreenivasulu R.; Cassidy, Patrick E.

    2003-01-01

    This report summarizes results from research on high performance polymers. The research areas proposed in this report include: 1) Effort to improve the synthesis and to understand and replicate the dielectric behavior of 6HC17-PEK; 2) Continue preparation and evaluation of flexible, low dielectric silicon- and fluorine- containing polymers with improved toughness; and 3) Synthesis and characterization of high performance polymers containing the spirodilactam moiety.

  15. High performance polymeric foams

    SciTech Connect

    Gargiulo, M.; Sorrentino, L.; Iannace, S.

    2008-08-28

    The aim of this work was to investigate the foamability of high-performance polymers (polyethersulfone, polyphenylsulfone, polyetherimide and polyethylenenaphtalate). Two different methods have been used to prepare the foam samples: high temperature expansion and two-stage batch process. The effects of processing parameters (saturation time and pressure, foaming temperature) on the densities and microcellular structures of these foams were analyzed by using scanning electron microscopy.

  16. High-temperature electronics

    NASA Astrophysics Data System (ADS)

    Matus, Lawrence G.; Seng, Gary T.

    1990-02-01

    To meet the needs of the aerospace propulsion and space power communities, the high temperature electronics program at the Lewis Research Center is developing silicon carbide (SiC) as a high temperature semiconductor material. This program supports a major element of the Center's mission - to perform basic and developmental research aimed at improving aerospace propulsion systems. Research is focused on developing the crystal growth, characterization, and device fabrication technologies necessary to produce a family of SiC devices.

  17. High power density targets

    NASA Astrophysics Data System (ADS)

    Pellemoine, Frederique

    2013-12-01

    In the context of new generation rare isotope beam facilities based on high-power heavy-ion accelerators and in-flight separation of the reaction products, the design of the rare isotope production targets is a major challenge. In order to provide high-purity beams for science, high resolution is required in the rare isotope separation. This demands a small beam spot on the production target which, together with the short range of heavy ions in matter, leads to very high power densities inside the target material. This paper gives an overview of the challenges associated with this high power density, discusses radiation damage issues in targets exposed to heavy ion beams, and presents recent developments to meet some of these challenges through different projects: FAIR, RIBF and FRIB which is the most challenging. Extensive use of Finite Element Analysis (FEA) has been made at all facilities to specify critical target parameters and R&D work at FRIB successfully retired two major risks related to high-power density and heavy-ion induced radiation damage.

  18. High Energy Continuum of High Redshift Quasars

    NASA Technical Reports Server (NTRS)

    Elvis, Martin

    2000-01-01

    Discussion with the RXTE team at GSFC showed that a sufficiently accurate background subtraction procedure had now, been derived for sources at the flux level of PKS 2126-158. However this solution does not apply to observations carried out before April 1997, including our observation. The prospect of an improved solution becoming available soon is slim. As a result the RXTE team agreed to re-observe PKS2126-158. The new observation was carried out in April 1999. Quasi-simultaneous optical observations were obtained, as Service observing., at the 4-meter Anglo-Australian Telescope, and ftp-ed from the AAT on 22April. The RXTE data was processed in late June, arriving at SAO in early July. Coincidentally, our collaborative Beppo-SAX observation of PKS2126-158 was made later in 1999, and a GTO Chandra observation (with which we are involved) was made on November 16. Since this gives us a unique monitoring data for a high redshift quasar over a broad pass-band we are now combining all three observations into a single comprehensive study Final publication of the RXTE data will thus take place under another grant.

  19. High Performance Arcjet Engines

    NASA Technical Reports Server (NTRS)

    Kennel, Elliot B.; Ivanov, Alexey Nikolayevich; Nikolayev, Yuri Vyacheslavovich

    1994-01-01

    This effort sought to exploit advanced single crystal tungsten-tantalum alloy material for fabrication of a high strength, high temperature arcjet anode. The use of this material is expected to result in improved strength, temperature resistance, and lifetime compared to state of the art polycrystalline alloys. In addition, the use of high electrical and thermal conductivity carbon-carbon composites was considered, and is believed to be a feasible approach. Highly conductive carbon-carbon composite anode capability represents enabling technology for rotating-arc designs derived from the Russian Scientific Research Institute of Thermal Processes (NIITP) because of high heat fluxes at the anode surface. However, for US designs the anode heat flux is much smaller, and thus the benefits are not as great as in the case of NIITP-derived designs. Still, it does appear that the tensile properties of carbon-carbon can be even better than those of single crystal tungsten alloys, especially when nearly-single-crystal fibers such as vapor grown carbon fiber (VGCF) are used. Composites fabricated from such materials must be coated with a refractory carbide coating in order to ensure compatibility with high temperature hydrogen. Fabrication of tungsten alloy single crystals in the sizes required for fabrication of an arcjet anode has been shown to be feasible. Test data indicate that the material can be expected to be at least the equal of W-Re-HfC polycrystalline alloy in terms of its tensile properties, and possibly superior. We are also informed by our colleagues at Scientific Production Association Luch (NP0 Luch) that it is possible to use Russian technology to fabricate polycrystalline W-Re-HfC or other high strength alloys if desired. This is important because existing engines must rely on previously accumulated stocks of these materials, and a fabrication capability for future requirements is not assured.

  20. High Beta Tokamaks

    SciTech Connect

    Cowley, S.

    1998-11-14

    Perhaps the ideal tokamak would have high {beta} ({beta} {approx}> 1) and classical confinement. Such a tokamak has not been found, and we do not know if one does exist. We have searched for such a possibility, so far without success. In 1990, we obtained analytic equilibrium solutions for large aspect ratio tokamaks at {beta} {approx} {Omicron}(1) [1]. These solutions and the extension at high {beta} poloidal to finite aspect ratio [2] provided a basis for the study of high {beta} tokamaks. We have shown that these configurations can be stable to short scale MHD modes [3], and that they have reduced neoclassical transport [4]. Microinstabilities (such as the {del}T{sub i} mode) seem to be stabilized at high {beta} [5] - this is due to the large local shear [3] and the magnetic well. We have some concerns about modes associated with the compressional branch which may appear at high {beta}. Bill Dorland and Mike Kotschenreuther have studied this issue and our concerns may be unfounded. It is certainly tantalizing, especially given the lowered neoclassical transport values, that these configurations could have no microinstabilities and, one could assume, no anomalous transport. Unfortunately, while this work is encouraging, the key question for high {beta} tokamaks is the stability to large scale kink modes. The MHD {beta} limit (Troyon limit) for kink modes at large aspect ratio is problematically low. There is ample evidence from computations that the limit exists. However, it is not known if stable equilibria exist at much higher {beta}--none have been found. We have explored this question in the asymptotic high {beta} poloidal limit. Unfortunately, we are unable to find stable equilibrium and also unable to show that they don't exist. The results of these calculations will be published when a more definitive answer is found.

  1. High Temperature Capacitor Development

    SciTech Connect

    John Kosek

    2009-06-30

    The absence of high-temperature electronics is an obstacle to the development of untapped energy resources (deep oil, gas and geothermal). US natural gas consumption is projected to grow from 22 trillion cubic feet per year (tcf) in 1999 to 34 tcf in 2020. Cumulatively this is 607 tcf of consumption by 2020, while recoverable reserves using current technology are 177 tcf. A significant portion of this shortfall may be met by tapping deep gas reservoirs. Tapping these reservoirs represents a significant technical challenge. At these depths, temperatures and pressures are very high and may require penetrating very hard rock. Logistics of supporting 6.1 km (20,000 ft) drill strings and the drilling processes are complex and expensive. At these depths up to 50% of the total drilling cost may be in the last 10% of the well depth. Thus, as wells go deeper it is increasingly important that drillers are able to monitor conditions down-hole such as temperature, pressure, heading, etc. Commercial off-the-shelf electronics are not specified to meet these operating conditions. This is due to problems associated with all aspects of the electronics including the resistors and capacitors. With respect to capacitors, increasing temperature often significantly changes capacitance because of the strong temperature dependence of the dielectric constant. Higher temperatures also affect the equivalent series resistance (ESR). High-temperature capacitors usually have low capacitance values because of these dielectric effects and because packages are kept small to prevent mechanical breakage caused by thermal stresses. Electrolytic capacitors do not operate at temperatures above 150oC due to dielectric breakdown. The development of high-temperature capacitors to be used in a high-pressure high-temperature (HPHT) drilling environment was investigated. These capacitors were based on a previously developed high-voltage hybridized capacitor developed at Giner, Inc. in conjunction with a

  2. High Altitude Medical Problems

    PubMed Central

    Hultgren, Herbert N.

    1979-01-01

    Increased travel to high altitude areas by mountaineers and nonclimbing tourists has emphasized the clinical problems associated with rapid ascent. Acute mountain sickness affects most sojourners at elevations above 10,000 feet. Symptoms are usually worse on the second or third day after arrival. Gradual ascent, spending one to three days at an intermediate altitude, and the use of acetazolamide (Diamox) will prevent or ameliorate symptoms in most instances. Serious and potentially fatal problems, such as high altitude pulmonary edema or cerebral edema, occur in approximately 0.5 percent to 1.0 percent of visitors to elevations above 10,000 feet—especially with heavy physical exertion on arrival, such as climbing or skiing. Early recognition, high flow oxygen therapy and prompt descent are crucially important in management. Our knowledge of the causes of these and other high altitude problems, such as retinal hemorrhage, systemic edema and pulmonary hypertension, is still incomplete. Even less is known of the effect of high altitudes on medical conditions common at sea level or on the action of commonly used drugs. ImagesFigure 2. PMID:483805

  3. HIGH POWER PULSED OSCILLATOR

    DOEpatents

    Singer, S.; Neher, L.K.

    1957-09-24

    A high powered, radio frequency pulse oscillator is described for generating trains of oscillations at the instant an input direct voltage is impressed, or immediately upon application of a light pulse. In one embodiment, the pulse oscillator comprises a photo-multiplier tube with the cathode connected to the first dynode by means of a resistor, and adjacent dynodes are connected to each other through adjustable resistors. The ohmage of the resistors progressively increases from a very low value for resistors adjacent the cathode to a high value adjacent the plate, the last dynode. Oscillation occurs with this circuit when a high negative voltage pulse is applied to the cathode and the photo cathode is bombarded. Another embodiment adds capacitors at the resistor connection points of the above circuit to increase the duration of the oscillator train.

  4. Bioremediation of high explosives

    SciTech Connect

    Kitts, C.L.; Alvarez, M.A.; Hanners, J.L.; Ogden, K.L.; Vanderberg-Twary, L.; Unkefer, P.J.

    1995-09-01

    Manufacture and use of high explosives has resulted in contamination of ground water and soils throughout the world. The use of biological methods for remediation of high explosives contamination has received considerable attention in recent years. Biodegradation is most easily studied using organisms in liquid cultures. Thus, the amount of explosive that can be degraded in liquid culture is quite small. However, these experiments are useful for gathering basic information about the biochemical pathways of biodegradation, identifying appropriate organisms and obtaining rates of degradation. The authors` laboratory has investigated all three major areas of explosives bioremediation: explosives in solution, explosives in soil, and the disposal of bulk explosives from demilitarization operations. They investigated the three explosives most commonly used in modern high explosive formulations: 2,4,6-trinitrotoluene (TNT), hexahydro 1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX).

  5. Highly Thermal Conductive Nanocomposites

    NASA Technical Reports Server (NTRS)

    Sun, Ya-Ping (Inventor); Connell, John W. (Inventor); Veca, Lucia Monica (Inventor)

    2015-01-01

    Disclosed are methods for forming carbon-based fillers as may be utilized in forming highly thermal conductive nanocomposite materials. Formation methods include treatment of an expanded graphite with an alcohol/water mixture followed by further exfoliation of the graphite to form extremely thin carbon nanosheets that are on the order of between about 2 and about 10 nanometers in thickness. Disclosed carbon nanosheets can be functionalized and/or can be incorporated in nanocomposites with extremely high thermal conductivities. Disclosed methods and materials can prove highly valuable in many technological applications including, for instance, in formation of heat management materials for protective clothing and as may be useful in space exploration or in others that require efficient yet light-weight and flexible thermal management solutions.

  6. High level nuclear waste

    SciTech Connect

    Crandall, J L

    1980-01-01

    The DOE Division of Waste Products through a lead office at Savannah River is developing a program to immobilize all US high-level nuclear waste for terminal disposal. DOE high-level wastes include those at the Hanford Plant, the Idaho Chemical Processing Plant, and the Savannah River Plant. Commercial high-level wastes, for which DOE is also developing immobilization technology, include those at the Nuclear Fuel Services Plant and any future commercial fuels reprocessing plants. The first immobilization plant is to be the Defense Waste Processing Facility at Savannah River, scheduled for 1983 project submission to Congress and 1989 operation. Waste forms are still being selected for this plant. Borosilicate glass is currently the reference form, but alternate candidates include concretes, calcines, other glasses, ceramics, and matrix forms.

  7. High brightness electron accelerator

    DOEpatents

    Sheffield, Richard L.; Carlsten, Bruce E.; Young, Lloyd M.

    1994-01-01

    A compact high brightness linear accelerator is provided for use, e.g., in a free electron laser. The accelerator has a first plurality of acclerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electons as the electrons enter the first cavity.

  8. High voltage power supply

    NASA Technical Reports Server (NTRS)

    Ruitberg, A. P.; Young, K. M. (Inventor)

    1985-01-01

    A high voltage power supply is formed by three discrete circuits energized by a battery to provide a plurality of concurrent output signals floating at a high output voltage on the order of several tens of kilovolts. In the first two circuits, the regulator stages are pulse width modulated and include adjustable ressistances for varying the duty cycles of pulse trains provided to corresponding oscillator stages while the third regulator stage includes an adjustable resistance for varying the amplitude of a steady signal provided to a third oscillator stage. In the first circuit, the oscillator, formed by a constant current drive network and a tuned resonant network included a step up transformer, is coupled to a second step up transformer which, in turn, supplies an amplified sinusoidal signal to a parallel pair of complementary poled rectifying, voltage multiplier stages to generate the high output voltage.

  9. High resolution data acquisition

    DOEpatents

    Thornton, Glenn W.; Fuller, Kenneth R.

    1993-01-01

    A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock (38) pulse train (37) and analog circuitry (44) for generating a triangular wave (46) synchronously with the pulse train (37). The triangular wave (46) has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter (18, 32) forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter (26) counts the clock pulse train (37) during the interval to form a gross event interval time. A computer (52) then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.

  10. High resolution data acquisition

    DOEpatents

    Thornton, G.W.; Fuller, K.R.

    1993-04-06

    A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock, pulse train, and analog circuitry for generating a triangular wave synchronously with the pulse train (as seen in diagram on patent). The triangular wave has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter counts the clock pulse train during the interval to form a gross event interval time. A computer then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.

  11. High temperature electronics technology

    NASA Astrophysics Data System (ADS)

    Dening, J. C.; Hurtle, D. E.

    1984-03-01

    This report summarizes the barrier metallization developments accomplished in a program intended to develop 300 C electronic controls capability for potential on-engine aircraft engine application. In addition, this report documents preliminary life test results at 300 C and above and discusses improved design practices required for high temperature integrated injection logic semiconductors. Previous Phase 1 activities focused on determining the viability of operating silicon semiconductor devices over the -55 C to +300 C temperature range. This feasibility was substantiated but the need for additional design work and process development was indicated. Phase 2 emphasized the development of a high temperature metallization system as the primary development need for high temperature silicon semiconductor applications.

  12. High temperature interface superconductivity

    NASA Astrophysics Data System (ADS)

    Gozar, A.; Bozovic, I.

    2016-02-01

    High-Tc superconductivity at interfaces has a history of more than a couple of decades. In this review we focus our attention on copper-oxide based heterostructures and multi-layers. We first discuss the technique, atomic layer-by-layer molecular beam epitaxy (ALL-MBE) engineering, that enabled High-Tc Interface Superconductivity (HT-IS), and the challenges associated with the realization of high quality interfaces. Then we turn our attention to the experiments which shed light on the structure and properties of interfacial layers, allowing comparison to those of single-phase films and bulk crystals. Both 'passive' hetero-structures as well as surface-induced effects by external gating are discussed. We conclude by comparing HT-IS in cuprates and in other classes of materials, especially Fe-based superconductors, and by examining the grand challenges currently laying ahead for the field.

  13. High Performance, Dependable Multiprocessor

    NASA Technical Reports Server (NTRS)

    Ramos, Jeremy; Samson, John R.; Troxel, Ian; Subramaniyan, Rajagopal; Jacobs, Adam; Greco, James; Cieslewski, Grzegorz; Curreri, John; Fischer, Michael; Grobelny, Eric; George, Alan; Aggarwal, Vikas; Patel, Minesh; Some, Raphael

    2006-01-01

    With the ever increasing demand for higher bandwidth and processing capacity of today's space exploration, space science, and defense missions, the ability to efficiently apply commercial-off-the-shelf (COTS) processors for on-board computing is now a critical need. In response to this need, NASA's New Millennium Program office has commissioned the development of Dependable Multiprocessor (DM) technology for use in payload and robotic missions. The Dependable Multiprocessor technology is a COTS-based, power efficient, high performance, highly dependable, fault tolerant cluster computer. To date, Honeywell has successfully demonstrated a TRL4 prototype of the Dependable Multiprocessor [I], and is now working on the development of a TRLS prototype. For the present effort Honeywell has teamed up with the University of Florida's High-performance Computing and Simulation (HCS) Lab, and together the team has demonstrated major elements of the Dependable Multiprocessor TRLS system.

  14. High-conflict divorce.

    PubMed

    Johnston, J R

    1994-01-01

    This article reviews available research studies of high-conflict divorce and its effects on children. Interparental conflict after divorce (defined as verbal and physical aggression, overt hostility, and distrust) and the primary parent's emotional distress are jointly predictive of more problematic parent-child relationships and greater child emotional and behavioral maladjustment. As a group, children of high-conflict divorce as defined above, especially boys, are two to four times more likely to be clinically disturbed in emotions and behavior compared with national norms. Court-ordered joint physical custody and frequent visitation arrangements in high-conflict divorce tend to be associated with poorer child outcomes, especially for girls. Types of intervention programs and social policy appropriate for these kinds of families are presented. PMID:7922278

  15. High temperature interface superconductivity

    DOE PAGESBeta

    Gozar, A.; Bozovic, I.

    2016-01-20

    High-Tc superconductivity at interfaces has a history of more than a couple of decades. In this review we focus our attention on copper-oxide based heterostructures and multi-layers. We first discuss the technique, atomic layer-by-layer molecular beam epitaxy (ALL-MBE) engineering, that enabled High-Tc Interface Superconductivity (HT-IS), and the challenges associated with the realization of high quality interfaces. Then we turn our attention to the experiments which shed light on the structure and properties of interfacial layers, allowing comparison to those of single-phase films and bulk crystals. Both ‘passive’ hetero-structures as well as surface-induced effects by external gating are discussed. Here, wemore » conclude by comparing HT-IS in cuprates and in other classes of materials, especially Fe-based superconductors, and by examining the grand challenges currently laying ahead for the field.« less

  16. High-energy detector

    DOEpatents

    Bolotnikov, Aleksey E.; Camarda, Giuseppe; Cui, Yonggang; James, Ralph B.

    2011-11-22

    The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.

  17. High School Principals and the High School Journalism Program.

    ERIC Educational Resources Information Center

    Peterson, Jane W.

    A study asked selected high school principals to respond to statements about the value of high school journalism to the high school student and about the rights and responsibilities of the high school journalist. These responses were then checked against such information as whether or not the high school principal had worked on a high school…

  18. High temperature electronics

    NASA Astrophysics Data System (ADS)

    Seng, Gary T.

    1991-03-01

    In recent years, the aerospace propulsion and space power communities have acknowledged a growing need for electronic devices that are capable of sustained high-temperature operation. Aeropropulsion applications for high-temperature electronic devices include engine ground test instrumentation such as multiplexers, analog-to-digital converters, and telemetry systems capable of withstanding hot section engine temperatures in excess of 600 C. Uncooled operation of control and condition monitoring systems in advanced supersonic aircraft would subject the electronics to temperatures in excess of 300 C. Similarly, engine-mounted integrated electronic sensors could reach temperatures which exceed 500 C. In addition to aeronautics, there are many other areas that could benefit from the existence of high-temperature electronic devices. Space applications include power electronic devices for space platforms and satellites. Since power electronics require radiators to shed waste heat, electronic devices that operate at higher temperatures would allow a reduction in radiator size. Terrestrial applications include deep-well drilling instrumentation, high power electronics, and nuclear reactor instrumentation and control. To meet the needs of the applications mentioned previously, the high-temperature electronics (HTE) program at the Lewis Research Center is developing silicon carbide (SiC) as a high-temperature semiconductor material. Research is focused on developing the crystal growth, growth modeling, characterization, and device fabrication technologies necessary to produce a family of SiC devices. Interest in SiC has grown dramatically in recent years due to solid advances in the technology. Much research remains to be performed, but SiC appears ready to emerge as a useful semiconductor material.

  19. High Performance FORTRAN

    NASA Technical Reports Server (NTRS)

    Mehrotra, Piyush

    1994-01-01

    High performance FORTRAN is a set of extensions for FORTRAN 90 designed to allow specification of data parallel algorithms. The programmer annotates the program with distribution directives to specify the desired layout of data. The underlying programming model provides a global name space and a single thread of control. Explicitly parallel constructs allow the expression of fairly controlled forms of parallelism in particular data parallelism. Thus the code is specified in a high level portable manner with no explicit tasking or communication statements. The goal is to allow architecture specific compilers to generate efficient code for a wide variety of architectures including SIMD, MIMD shared and distributed memory machines.

  20. High Brightness Test Stand

    SciTech Connect

    Birx, D.L.; Caporaso, G.J.; Boyd, J.K.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L.; Rogers, D. Jr.; Smith, M.W.

    1985-08-07

    The High Brightness Test Stand is a 2 MeV, less than or equal to 10 kA electron accelerator module. This accelerator module, designed as an upgrade prototype for the Advanced Test Accelerator (ATA), combines solid state nonlinear magnetic drives with state-of-the-art induction linac technology. The facility serves a dual role, as it not only provides a test bed for this new technology, but is used to develop high brightness electron optics. We will both further describe the accelerator, as well as present some of the preliminary electron optics measurements.

  1. Highly compliant transparent electrodes

    NASA Astrophysics Data System (ADS)

    Shian, Samuel; Diebold, Roger M.; McNamara, Alena; Clarke, David R.

    2012-08-01

    Adaptive optical devices based on electric field induced deformation of dielectric elastomers require transparent and highly compliant electrodes to conform to large shape changes. Electrical, optical, and actuation properties of acrylic elastomer electrodes fabricated with single-walled carbon nanotubes (SWCNTs) and silver nanowires (AgNWs) have been evaluated. Based on these properties, a figure of merit is introduced for evaluating the overall performance of deformable transparent electrodes. This clearly indicates that SWCNTs outperform AgNWs. Under optimal conditions, optical transparency as high as 91% at 190% maximum actuation strain is readily achievable using SWCNT electrodes.

  2. High Availability Electronics Standards

    SciTech Connect

    Larsen, R.S.; /SLAC

    2006-12-13

    Availability modeling of the proposed International Linear Collider (ILC) predicts unacceptably low uptime with current electronics systems designs. High Availability (HA) analysis is being used as a guideline for all major machine systems including sources, utilities, cryogenics, magnets, power supplies, instrumentation and controls. R&D teams are seeking to achieve total machine high availability with nominal impact on system cost. The focus of this paper is the investigation of commercial standard HA architectures and packaging for Accelerator Controls and Instrumentation. Application of HA design principles to power systems and detector instrumentation are also discussed.

  3. High Energy Astrophysics Program

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This report reviews activities performed by members of the USRA (Universities Space Research Association) contract team during the six months during the reporting period (10/95 - 3/96) and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, within the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics. Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA), X-ray Timing Experiment (XTE), X-ray Spectrometer (XRS), Astro-E, High Energy Astrophysics Science, Archive Research Center (HEASARC), and others.

  4. High Energy Astrophysics Program

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This report reviews activities performed-by members of the USRA contract team during the six months of the reporting period and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, visiting the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics. Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA); X-ray Timing Experiment (XTE); X-ray Spectrometer (XRS); Astro-E; High Energy Astrophysics Science Archive Research Center (HEASARC), and others.

  5. High strength alloys

    SciTech Connect

    Maziasz, Phillip James; Shingledecker, John Paul; Santella, Michael Leonard; Schneibel, Joachim Hugo; Sikka, Vinod Kumar; Vinegar, Harold J.; John, Randy Carl; Kim, Dong Sub

    2012-06-05

    High strength metal alloys are described herein. At least one composition of a metal alloy includes chromium, nickel, copper, manganese, silicon, niobium, tungsten and iron. System, methods, and heaters that include the high strength metal alloys are described herein. At least one heater system may include a canister at least partially made from material containing at least one of the metal alloys. At least one system for heating a subterranean formation may include a tublar that is at least partially made from a material containing at least one of the metal alloys.

  6. High strength alloys

    SciTech Connect

    Maziasz, Phillip James; Shingledecker, John Paul; Santella, Michael Leonard; Schneibel, Joachim Hugo; Sikka, Vinod Kumar; Vinegar, Harold J; John, Randy Carl; Kim, Dong Sub

    2010-08-31

    High strength metal alloys are described herein. At least one composition of a metal alloy includes chromium, nickel, copper, manganese, silicon, niobium, tungsten and iron. System, methods, and heaters that include the high strength metal alloys are described herein. At least one heater system may include a canister at least partially made from material containing at least one of the metal alloys. At least one system for heating a subterranean formation may include a tubular that is at least partially made from a material containing at least one of the metal alloys.

  7. Delirium at high altitude.

    PubMed

    Basnyat, Buddha

    2002-01-01

    A 35-year-old man on a trek to the Mount Everest region of Nepal presented with a sudden, acute confusional state at an altitude of about 5000 m. Although described at higher altitudes, delirium presenting alone has not been documented at 5000 m or at lower high altitudes. The differential diagnosis which includes acute mountain sickness and high altitude cerebral edema is discussed. Finally, the importance of travelling with a reliable partner and using proper insurance is emphasized in treks to the Himalayas. PMID:12006167

  8. High intensity hadron accelerators

    SciTech Connect

    Teng, L.C.

    1989-05-01

    This rapporteur report consists mainly of two parts. Part I is an abridged review of the status of all High Intensity Hadron Accelerator projects in the world in semi-tabulated form for quick reference and comparison. Part II is a brief discussion of the salient features of the different technologies involved. The discussion is based mainly on my personal experiences and opinions, tempered, I hope, by the discussions I participated in in the various parallel sessions of the workshop. In addition, appended at the end is my evaluation and expression of the merits of high intensity hadron accelerators as research facilities for nuclear and particle physics.

  9. High Median Nerve Injuries.

    PubMed

    Isaacs, Jonathan; Ugwu-Oju, Obinna

    2016-08-01

    The median nerve serves a crucial role in extrinsic and intrinsic motor and sensory function to the radial half of the hand. High median nerve injuries, defined as injuries proximal to the anterior interosseous nerve origin, therefore typically result in significant functional loss prompting aggressive surgical management. Even with appropriate recognition and contemporary nerve reconstruction, however, motor and sensory recovery may be inadequate. With isolated persistent high median nerve palsies, a variety of available tendon transfers can improve key motor functions and salvage acceptable use of the hand. PMID:27387077

  10. Prevention of High Blood Pressure

    MedlinePlus

    ... page from the NHLBI on Twitter. Prevention of High Blood Pressure Healthy lifestyle habits, proper use of medicines, and ... prevent high blood pressure or its complications. Preventing High Blood Pressure Onset Healthy lifestyle habits can help prevent high ...

  11. High Blood Pressure in Pregnancy

    MedlinePlus

    ... The Health Information Center High Blood Pressure in Pregnancy What Is High Blood Pressure? Blood pressure is ... Are the Effects of High Blood Pressure in Pregnancy? Although many pregnant women with high blood pressure ...

  12. High speed door assembly

    DOEpatents

    Shapiro, Carolyn

    1993-01-01

    A high speed door assembly, comprising an actuator cylinder and piston rods, a pressure supply cylinder and fittings, an electrically detonated explosive bolt, a honeycomb structured door, a honeycomb structured decelerator, and a structural steel frame encasing the assembly to close over a 3 foot diameter opening within 50 milliseconds of actuation, to contain hazardous materials and vapors within a test fixture.

  13. High speed door assembly

    DOEpatents

    Shapiro, C.

    1993-04-27

    A high speed door assembly is described, comprising an actuator cylinder and piston rods, a pressure supply cylinder and fittings, an electrically detonated explosive bolt, a honeycomb structured door, a honeycomb structured decelerator, and a structural steel frame encasing the assembly to close over a 3 foot diameter opening within 50 milliseconds of actuation, to contain hazardous materials and vapors within a test fixture.

  14. High surface area calcite

    NASA Astrophysics Data System (ADS)

    Schultz, L. N.; Andersson, M. P.; Dalby, K. N.; Müter, D.; Okhrimenko, D. V.; Fordsmand, H.; Stipp, S. L. S.

    2013-05-01

    Calcite (CaCO3) is important in many fields—in nature, because it is a component of aquifers, oil reservoirs and prospective CO2 storage sites, and in industry, where it is used in products as diverse as paper, toothpaste, paint, plastic and aspirin. It is difficult to obtain high purity calcite with a high surface area but such material is necessary for industrial applications and for fundamental calcite research. Commercial powder is nearly always contaminated with growth inhibitors such as sugars, citrate or pectin and most laboratory synthesis methods deliver large precipitates, often containing vaterite or aragonite. To address this problem, we (i) adapted the method of carbonating a Ca(OH)2 slurry with CO2 gas to develop the first simple, cheap, safe and reproducible procedure using common laboratory equipment, to obtain calcite that reproducibly had a surface area of 14-17 m2/g and (ii) conducted a thorough characterization of the product. Scanning electron microscopy (SEM) revealed nanometer scale, rhombohedral crystals. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR) confirmed highly crystalline, pure calcite that more closely resembles the dimensions of the biogenic calcite produced by algae in coccoliths than other methods for synthesizing calcite. We suggest that this calcite is useful when purity and high surface area are important.

  15. High Temperature Piezoelectric Drill

    NASA Technical Reports Server (NTRS)

    Bao, Xiaoqi; Scott, James; Boudreau, Kate; Bar-Cohen, Yoseph; Sherrit, Stewart; Badescu, Mircea; Shrout, Tom; Zhang, Shujun

    2009-01-01

    The current NASA Decadal mission planning effort has identified Venus as a significant scientific target for a surface in-situ sampling/analyzing mission. The Venus environment represents several extremes including high temperature (460 deg C), high pressure (9 MPa), and potentially corrosive (condensed sulfuric acid droplets that adhere to surfaces during entry) environments. This technology challenge requires new rock sampling tools for these extreme conditions. Piezoelectric materials can potentially operate over a wide temperature range. Single crystals, like LiNbO3, have a Curie temperature that is higher than 1000 deg C and the piezoelectric ceramics Bismuth Titanate higher than 600 deg C. A study of the feasibility of producing piezoelectric drills that can operate in the temperature range up to 500 deg C was conducted. The study includes the high temperature properties investigations of engineering materials and piezoelectric ceramics with different formulas and doping. The drilling performances of a prototype Ultrasonic/Sonic Drill/Corer (USDC) using high temperate piezoelectric ceramics and single crystal were tested at temperature up to 500 deg C. The detailed results of our study and a discussion of the future work on performance improvements are presented in this paper.

  16. Thinking Big, Aiming High

    ERIC Educational Resources Information Center

    Berkeley, Viv

    2010-01-01

    What do teachers, providers and policymakers need to do in order to support disabled learners to "think big and aim high"? That was the question put to delegates at NIACE's annual disability conference. Some clear themes emerged, with delegates raising concerns about funding, teacher training, partnership-working and employment for disabled…

  17. Executive High School Internships

    ERIC Educational Resources Information Center

    Hirsch, Sharlene Pearlman

    1974-01-01

    The Executive High School Internships Program enables juniors and seniors to take a one-semester sabbatical from their studies to serve as special assistants to executives in government, business, non-profit organizations, and civic organizations. They perform a variety of duties, earning full academic credit for their participation. (AG)

  18. Naperville High School

    ERIC Educational Resources Information Center

    Robert Wood Johnson Foundation, 2012

    2012-01-01

    In a political climate where most public schools have reduced or eliminated P.E. entirely in response to budget cuts and increased pressure to improve academic test scores, Naperville High School in Illinois stands out as an anomaly. The school's already robust daily P.E. program is specifically designed around the notion that physical activity…

  19. Saving America's High Schools

    ERIC Educational Resources Information Center

    Smerdon, Becky, Ed.; Borman, Kathryn M., Ed.

    2009-01-01

    Our educational system is in a continuous state of reform, yet outcomes are nowhere near what we can accept. Though the search for answers is perpetual, many efforts over the past decade have homed in on one feature of high schools--their size. If we simply reduce school size, the argument goes, students will gain a safer environment that can…

  20. High School Press Pressures.

    ERIC Educational Resources Information Center

    Rogers, Luella P.

    History shows that the high school press suffers through cycles that reflect economic factors and cultural climates within communities, states, and the nation. The direction of that cycle in the 1960s and early 1970s was toward more open, free-flowing information by a vigorous student press, but those economic and cultural signs now are pointing…

  1. High energy particle astronomy.

    NASA Technical Reports Server (NTRS)

    Buffington, A.; Muller, R. A.; Smith, L. H.; Smoot, G. F.

    1972-01-01

    Discussion of techniques currently used in high energy particle astronomy for measuring charged and neutral cosmic rays and their isotope and momentum distribution. Derived from methods developed for accelerator experiments in particle physics, these techniques help perform important particle astronomy experiments pertaining to nuclear cosmic ray and gamma ray research, electron and position probes, and antimatter searches.

  2. Highly oxidized superconductors

    DOEpatents

    Morris, D.E.

    1994-09-20

    Novel superconducting materials in the form of compounds, structures or phases are formed by performing otherwise known synthesis in a highly oxidizing atmosphere rather than that created by molecular oxygen at atmospheric pressure or below. This leads to the successful synthesis of novel superconducting compounds which are thermodynamically stable at the conditions under which they are formed. 16 figs.

  3. HIGH VOLTAGE REGULATOR

    DOEpatents

    Wright, B.T.

    1959-06-01

    A high voltage regulator for use with calutrons is described which rapidly restores accelerating voltage after a sudden drop such as is caused by sparking. The rapid restoration characteristic prevents excessive contamination of lighter mass receiver pockets by the heavier mass portion of the beam. (T.R.H.)

  4. High purity tungsten targets

    NASA Technical Reports Server (NTRS)

    1975-01-01

    High purity tungsten, which is used for targets in X-ray tubes was considered for space processing. The demand for X-ray tubes was calculated using the growth rates for dental and medical X-ray machines. It is concluded that the cost benefits are uncertain.

  5. High School & Youth Trends

    ERIC Educational Resources Information Center

    National Institute on Drug Abuse (NIDA), 2006

    2006-01-01

    Since 1975, the Monitoring the Future (MTF) survey has annually studied the extent of drug use among high school 12th-graders. The survey was expanded in 1991 to include 8th- and 10th graders. It is funded by the National Institute on Drug Abuse (NIDA) and is conducted by the University of Michigan's Institute for Social Research. The goal of…

  6. Compact high voltage battery

    SciTech Connect

    Kinsman, G.F.; Land, E.H.

    1980-03-18

    A high voltage, low impedance laminar battery comprising a stack of series connected cells confined under pressure in a housing is described. The cells comprise laminar anodes, cathodes and separators. The cells are connected in series by laminar conductive intercell connectors. An annular spacer is associated with each cell. The spacers are separated by interdigitated ones of the separators and intercell connectors.

  7. PRODUCING HIGH CORN YIELDS.

    ERIC Educational Resources Information Center

    Illinois Univ., Urbana. Coll. of Agriculture.

    RESOURCE MATERIAL ON CORN PRODUCTION FOR HIGH SCHOOL VOCATIONAL AGRICULTURE AND ADULT FARMER CLASSES WAS DESIGNED BY A STATE LEVEL GROUP OF SUBJECT MATTER SPECIALISTS, TEACHER EDUCATORS, SUPERVISORS, AND TEACHERS TO HELP SOLVE PROBLEMS THAT CONFRONT CORN PRODUCERS AT PLANTING TIME. THE SUBJECT MATTER CONCERNS PLANTING TIME, DEPTH, ROW WIDTH,…

  8. High School's New Face

    ERIC Educational Resources Information Center

    Furger, Roberta

    2004-01-01

    No longer limited to the classroom, educators move to close the gap between school and the real world. Transforming high schools has been likened to turning an ocean liner around: It involves slow progress seemingly measured in inches, rather than yards or miles. This report discusses how educators move to close to gap between school and the real…

  9. High Impact Instruction

    ERIC Educational Resources Information Center

    Knight, Jim

    2013-01-01

    The key to improving student achievement isn't more teacher time--it's more teacher impact. But how do you decide which instructional practices will deliver the most bang for your buck? In this handbook, written for teachers but suitable for use by principals and instructional coaches, best-selling author Jim Knight presents the high-leverage…

  10. Reshaping High School English.

    ERIC Educational Resources Information Center

    Pirie, Bruce

    This book takes up the question of what shape high school English studies should take in the coming years. It describes an English program that blends philosophical depth with classroom practicality. Drawing examples from commonly taught texts such as "Macbeth,""To Kill a Mockingbird," and "Lord of the Flies," the book places literary analysis…

  11. The Runner's High.

    ERIC Educational Resources Information Center

    Sachs, Michael L.

    Research concerning the euphoric state known as "the runner's high" is reviewed in an attempt to determine psychological factors behind the experience. Possible factors include cerebral dominance, relaxation, environmental influences, time and/or distance of run, and absence of personal problems. A list of references and several descriptions of…

  12. Investing in High School

    ERIC Educational Resources Information Center

    Green, Daniel G.

    2012-01-01

    Strapped for cash, a Massachusetts high school creates its own venture capital fund to incentivize teachers to create programs that improve student learning. The result has been higher test scores and higher job satisfaction. One important program is credited with helping close the achievement gap at the school, while others have helped ambitious…

  13. High Relief Block Printing.

    ERIC Educational Resources Information Center

    Foster, Michael

    1989-01-01

    Explains a method of block printing using styrofoam shapes to make high relief. Describes the creation of the block design as well as the actual printing process. Uses a range of paper types for printing so children can see the results of using different media. (LS)

  14. Maintaining High Expectations

    ERIC Educational Resources Information Center

    Williams, Roger; Williams, Sherry

    2014-01-01

    Author and husband, Roger Williams, is hearing and signs fluently, and author and wife, Sherry Williams, is deaf and uses both speech and signs, although she is most comfortable signing. As parents of six children--deaf and hearing--they are determined to encourage their children to do their best, and they always set their expectations high. They…

  15. Becoming "Highly Qualified"

    ERIC Educational Resources Information Center

    Quigley, Kimberly; Gomez, Cristina

    2006-01-01

    The Data Analysis for Teachers course helps teachers to learn instructional strategies, and make them "highly qualified" to teach mathematics for understanding. Going through the process of asking statistical questions, collecting appropriate data, analyzing the data, and interpreting the data was very exciting and students responded well when…

  16. CSTI High Capacity Power

    NASA Technical Reports Server (NTRS)

    Winter, Jerry M.

    1989-01-01

    The SP-100 program was established in 1983 by DOD, DOE, and NASA as a joint program to develop the technology necessary for space nuclear power systems for military and civil application. During FY-86 and 87, the NASA SP-100 Advanced Technology Program was devised to maintain the momentum of promising technology advancement efforts started during Phase 1 of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for future space applications. In FY-88, the Advanced Technology Program was incorporated into NASA's new Civil Space Technology Initiative (CSTI). The CSTI Program was established to provide the foundation for technology development in automation and robotics, information, propulsion, and power. The CSTI High Capacity Power Program builds on the technology efforts of the SP-100 program, incorporates the previous NASA SP-100 Advanced Technology project, and provides a bridge to NASA Project Pathfinder. The elements of CSTI High Capacity Power development include Conversion Systems, Thermal Management, Power Management, System Diagnostics, and Environmental Interactions. Technology advancement in all areas, including materials, is required to assure the high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall program will develop and demonstrate the technology base required to provide a wide range of modular power systems as well as allowing mission independence from solar and orbital attitude requirements. Several recent advancements in CSTI High Capacity power development will be discussed.

  17. [Senior High School Program.

    ERIC Educational Resources Information Center

    Wisconsin Univ. - Stout, Menomonie. Center for Vocational, Technical and Adult Education.

    This student directed document contains five activity packages, a proposed curriculum, and a set of transparency masters; all pertain to field objectives 1, 4, or 5 of the Wisconsin Guide to Local Curriculum Improvement in Industrial Education, K-12. Geared to the junior and senior high school level, the packages are entitled: Co-op Program…

  18. Saving One High School.

    ERIC Educational Resources Information Center

    Noah, Timothy

    1988-01-01

    Describes the improved learning environment at Orangeburg-Wilkinson High School in South Carolina and gives credit to Principal Melvin Smoak. Discusses such topics as discipline policy, teacher evaluation, and remedial programs. States that, although more students are acquiring basic skills, the school has no resources to challenge the brightest…

  19. High expression Zymomonas promoters

    DOEpatents

    Viitanen, Paul V.; Tao, Luan; Zhang, Yuying; Caimi, Perry G.; McCole, Laura : Zhang, Min; Chou, Yat-Chen; McCutchen, Carol M.; Franden, Mary Ann

    2011-08-02

    Identified are mutants of the promoter of the Z. mobilis glyceraldehyde-3-phosphate dehydrogenase gene, which direct improved expression levels of operably linked heterologous nucleic acids. These are high expression promoters useful for expression of chimeric genes in Zymomonas, Zymobacter, and other related bacteria.

  20. Stony Pont High School.

    ERIC Educational Resources Information Center

    Design Cost Data, 2001

    2001-01-01

    Includes information about the building site, architectural design, master plan, materials, costs, scheduling, specifications, and square footage for the 86-acre Stony Point High School in Round Rock, Texas. Includes floor plan, general description, photos, and a list of manufacturers and suppliers used for the project. (GR)

  1. High-School Village.

    ERIC Educational Resources Information Center

    Cotton, Bob

    2002-01-01

    Portrays the Sandra Day O'Connor High School in Helotes, Texas, whose architectural design, materials, and building forms reflect a rural Texas setting and a community wish that the large campus not overpower the nearby town. Includes photographs and a site plan. (GR)

  2. High performance parallel architectures

    SciTech Connect

    Anderson, R.E. )

    1989-09-01

    In this paper the author describes current high performance parallel computer architectures. A taxonomy is presented to show computer architecture from the user programmer's point-of-view. The effects of the taxonomy upon the programming model are described. Some current architectures are described with respect to the taxonomy. Finally, some predictions about future systems are presented. 5 refs., 1 fig.

  3. Highly oxidized superconductors

    DOEpatents

    Morris, Donald E.

    1994-01-01

    Novel superconducting materials in the form of compounds, structures or phases are formed by performing otherwise known syntheses in a highly oxidizing atmosphere rather than that created by molecular oxygen at atmospheric pressure or below. This leads to the successful synthesis of novel superconducting compounds which are thermodynamically stable at the conditions under which they are formed.

  4. Carthage High School Baseball.

    ERIC Educational Resources Information Center

    Woodfin, Samantha, Ed.

    1995-01-01

    This is the third issue of the magazine to focus on baseball in Panola County (Texas). The issue salutes the Carthage High School baseball program during two periods of its history. The first period was the early 1940's under Coach E. B. Morrison, whose teams were State Finalists in 1941 and 1942. The second period covered is the era of Coach…

  5. High-Performance Happy

    ERIC Educational Resources Information Center

    O'Hanlon, Charlene

    2007-01-01

    Traditionally, the high-performance computing (HPC) systems used to conduct research at universities have amounted to silos of technology scattered across the campus and falling under the purview of the researchers themselves. This article reports that a growing number of universities are now taking over the management of those systems and…

  6. High-Sensitivity Spectrophotometry.

    ERIC Educational Resources Information Center

    Harris, T. D.

    1982-01-01

    Selected high-sensitivity spectrophotometric methods are examined, and comparisons are made of their relative strengths and weaknesses and the circumstances for which each can best be applied. Methods include long path cells, noise reduction, laser intracavity absorption, thermocouple calorimetry, photoacoustic methods, and thermo-optical methods.…

  7. High-Stakes Trouble.

    ERIC Educational Resources Information Center

    Howe, Harold II

    2000-01-01

    Critiquing Nina and Sol Horowitz's article advocating high-stakes tests, the author deplores deleterious effects of too-rigorous standards on poor students and recent immigrants. Without large-scale initiatives to affect their lives out of school, urban youngsters' prospects are dim. A National Research Council report offers testing guidelines.…

  8. High Power Cryogenic Targets

    SciTech Connect

    Gregory Smith

    2011-08-01

    The development of high power cryogenic targets for use in parity violating electron scattering has been a crucial ingredient in the success of those experiments. As we chase the precision frontier, the demands and requirements for these targets have grown accordingly. We discuss the state of the art, and describe recent developments and strategies in the design of the next generation of these targets.

  9. High strength composites evaluation

    SciTech Connect

    Marten, S.M.

    1992-02-01

    A high-strength, thick-section, graphite/epoxy composite was identified. The purpose of this development effort was to evaluate candidate materials and provide LANL with engineering properties. Eight candidate materials (Samples 1000, 1100, 1200, 1300, 1400, 1500, 1600, and 1700) were chosen for evaluation. The Sample 1700 thermoplastic material was the strongest overall.

  10. High-resolution echocardiography

    NASA Technical Reports Server (NTRS)

    Nathan, R.

    1979-01-01

    High resolution computer aided ultrasound system provides two-and three-dimensional images of beating heart from many angles. System provides means for determining whether small blood vessels around the heart are blocked or if heart wall is moving normally without interference of dead and noncontracting muscle tissue.

  11. Revisiting High School Visits

    ERIC Educational Resources Information Center

    Flagel, Andrew

    2012-01-01

    NACAC's anniversary is a great time to follow up on an article on high school visits, a topic of ongoing discussion in every admission and guidance office. The article highlights a variety of potential good outcomes that can be derived from collaborative interactions. Sadly, however, admission representatives are apt to be described by the…

  12. High Energy Astronomy Observatory

    NASA Technical Reports Server (NTRS)

    1980-01-01

    An overview of the High Energy Astronomy Observatory 2 contributions to X-ray astronomy is presented along with a brief description of the satellite and onboard telescope. Observations relating to galaxies and galactic clusters, black holes, supernova remnants, quasars, and cosmology are discussed.

  13. High-resolution headlamp

    NASA Astrophysics Data System (ADS)

    Gut, Carsten; Cristea, Iulia; Neumann, Cornelius

    2016-04-01

    The following article shall describe how human vision by night can be influenced. At first, front lighting systems that are already available on the market will be described, followed by their analysis with respect to the positive effects on traffic safety. Furthermore, how traffic safety by night can be increased since the introduction of high resolution headlamps shall be discussed.

  14. High Power Proton Facilities

    NASA Astrophysics Data System (ADS)

    Nagaitsev, Sergei

    2015-04-01

    This presentation will provide an overview of the capabilities and challenges of high intensity proton accelerators, such as J-PARC, Fermilab MI, SNS, ISIS, PSI, ESS (in the future) and others. The presentation will focus on lessons learned, new concepts, beam loss mechanisms and methods to mitigate them.

  15. Nongrading the High School.

    ERIC Educational Resources Information Center

    Jenkins, John M.

    1998-01-01

    Reviews the history of nongraded high schools, from Preston Search's pioneering efforts in Pueblo, Colorado, to early 1900s Dalton and Winnetka Plans and midcentury continuous-progress plans. Competency, not age, already determines participation in band, orchestra, choir, and athletics. Curricula should be based on the structure, methodology, and…

  16. Recovery High Schools

    ERIC Educational Resources Information Center

    Vogel, Carl

    2009-01-01

    This article discusses recovery high schools which are designed specifically to serve students who have been through a professional substance abuse treatment program and are working to stay away from drugs and alcohol. The schools typically serve multiple districts and are funded from both the per-pupil state funds that follow a student and what…

  17. High-fiber foods

    MedlinePlus

    Dietary fiber - self-care ... Dietary fiber adds bulk to your diet. Because it makes you feel full faster, it can help you ... Grains are another important source of dietary fiber. Eat more: ... Whole-grain breads Brown rice Popcorn High-fiber cereals, such ...

  18. High efficiency RCCI combustion

    NASA Astrophysics Data System (ADS)

    Splitter, Derek A.

    An experimental investigation of the pragmatic limits of Reactivity Controlled Compression Ignition (RCCI) engine efficiency was performed. The study utilized engine experiments combined with zero-dimensional modeling. Initially, simulations were used to suggest conditions of high engine efficiency with RCCI. Preliminary simulations suggested that high efficiency could be obtained by using a very dilute charge with a high compression ratio. Moreover, the preliminary simulations further suggested that with simultaneous 50% reductions in heat transfer and incomplete combustion, 60% gross thermal efficiency may be achievable with RCCI. Following the initial simulations, experiments to investigate the combustion process, fuel effects, and methods to reduce heat transfer and incomplete combustion reduction were conducted. The results demonstrated that the engine cycle and combustion process are linked, and if high efficiency is to be had, then the combustion event must be tailored to the initial cycle conditions. It was found that reductions to engine heat transfer are a key enabler to increasing engine efficiency. In addition, it was found that the piston oil jet gallery cooling in RCCI may be unnecessary, as it had a negative impact on efficiency. Without piston oil gallery cooling, it was found that RCCI was nearly adiabatic, achieving 95% of the theoretical maximum cycle efficiency (air standard Otto cycle efficiency).

  19. CSTI high capacity power

    SciTech Connect

    Winter, J.M.

    1994-09-01

    The SP-100 program was established in 1983 by DOD, DOE, and NASA as a joint program to develop the technology necessary for space nuclear power systems for military and civil application. During FY86 and 87, the NASA SP-100 Advanced Technology Program was devised to maintain the momentum of promising technology advancement efforts started during Phase I of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for future space applications. In FY88, the Advanced Technology Program was incorporated into NASA`s new Civil Space Technology Initiative (CSTI). The CSTI Program was established to provide the foundation for technology development in automation and robotics, information, propulsion, and power. The CSTI High Capacity Power Program builds on the technology efforts of the SP-100 program, incorporates the previous NASA SP-100 Advanced Technology project, and provides a bridge to NASA Project Pathfinder. The elements of CSTI High Capacity Power development include Conversion Systems, Thermal Management, Power Management, System Diagnostics, and Environmental Interactions. Technology advancement in all areas, including materials, is required to assure the high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall program will develop and demonstrate the technology base required to provide a wide range of modular power systems as well as allowing mission independence from solar and orbital attitude requirements. Several recent advancements in CSTI High Capacity power development will be discussed.

  20. High resolution drift chambers

    SciTech Connect

    Va'vra, J.

    1985-07-01

    High precision drift chambers capable of achieving less than or equal to 50 ..mu..m resolutions are discussed. In particular, we compare so called cool and hot gases, various charge collection geometries, several timing techniques and we also discuss some systematic problems. We also present what we would consider an ''ultimate'' design of the vertex chamber. 50 refs., 36 figs., 6 tabs.

  1. High School Projects.

    ERIC Educational Resources Information Center

    Learning By Design, 2002

    2002-01-01

    Describes the buildings of 30 high schools, including the educational context and design goals. Includes information on the architects and design team, a general building description, and general construction costs and specifications. Also provides a rough site plan and photographs. (EV)

  2. High Selectivity Oxygen Delignification

    SciTech Connect

    Arthur J. Ragauskas Lucian A. Lucia Hasan Jameel

    2005-09-30

    The overall objective of this program was to develop improved extended oxygen delignification (EOD) technologies for current U.S. pulp mill operations. This was accomplished by: (1) Identifying pulping conditions that optimize O and OO performance; (2) Identifying structural features of lignin that enhance reactivity towards EOD of high kappa pulps; (3) Identifying factors minimizing carbohydrate degradation and improve pulp strength of EOD high kappa pulps; (4) Developing a simple, reproducible method of quantifying yield gains from EOD; and (5) Developing process conditions that significantly reduce the capital requirements of EOD while optimizing the yield benefits. Key research outcomes included, demonstrating the use of a mini-O sequence such as (E+O)Dkf:0.05(E+O) or Dkf:0.05(E+O)(E+O) without interstage washing could capture approximately 60% of the delignification efficiency of a conventional O-stage without the major capital requirements associated with an O-stage for conventional SW kraft pulps. The rate of formation and loss of fiber charge during an O-stage stage can be employed to maximize net fiber charge. Optimal fiber charge development and delignification are two independent parameters and do not parallel each other. It is possible to utilize an O-stage to enhance overall cellulosic fiber charge of low and high kappa SW kraft pulps which is beneficial for physical strength properties. The application of NIR and multi-variant analysis was developed into a rapid and simple method of determining the yield of pulp from an oxygen delignification stage that has real-world mill applications. A focus point of this program was the demonstration that Kraft pulping conditions and oxygen delignification of high and low-kappa SW and HW pulps are intimately related. Improved physical pulp properties and yield can be delivered by controlling the H-factor and active alkali charge. Low AA softwood kraft pulp with a kappa number 30 has an average improvement of 2% in

  3. High mass stars: starbursts

    NASA Astrophysics Data System (ADS)

    González Delgado, R. M.

    2006-08-01

    Starbursts are the preferred place where massive stars form; the main source of thermal and mechanical heating in the interstellar medium, and the factory where the heavy elements form. Thus, starbursts play an important role in the origin and evolution of galaxies. Starbursts are bright at ultraviolet (UV) wavelengths, and after the pioneering IUE program, high spatial and spectral resolution UV observations of local starburst galaxies, mainly taken with HST and FUSE, have made relevant contributions to the following issues: a) The determination of the initial mass function in violent star forming systems in low and high metallicity environments, and in dense (e.g. in stellar clusters) and diffuse environments. b) The modes of star formation: Starburst clusters are an important mode of star formation. c) The role of starbursts in AGN. d) The interaction between massive stars and the interstellar and intergalactic media. e) The contribution of starbursts to the reionization of the universe. Despite the very significant progress obtained over the past two decades of UV observations of starbursts, there are important problems that still need to be solved. High-spatial resolution UV observations of nearby starbursts are crucial to further progress in understanding the violent star formation processes in galaxies, the interaction between the stellar clusters and the interstellar medium, and the variation of the IMF. Thus, a new UV mission furnished with an intermediate spectral resolution long-slit spectrograph with high spatial resolution and high UV sensitivity is required to further progress in the study of starburst galaxies and their impact on the evolution of galaxies.

  4. High Voltage Seismic Generator

    NASA Astrophysics Data System (ADS)

    Bogacz, Adrian; Pala, Damian; Knafel, Marcin

    2015-04-01

    This contribution describes the preliminary result of annual cooperation of three student research groups from AGH UST in Krakow, Poland. The aim of this cooperation was to develop and construct a high voltage seismic wave generator. Constructed device uses a high-energy electrical discharge to generate seismic wave in ground. This type of device can be applied in several different methods of seismic measurement, but because of its limited power it is mainly dedicated for engineering geophysics. The source operates on a basic physical principles. The energy is stored in capacitor bank, which is charged by two stage low to high voltage converter. Stored energy is then released in very short time through high voltage thyristor in spark gap. The whole appliance is powered from li-ion battery and controlled by ATmega microcontroller. It is possible to construct larger and more powerful device. In this contribution the structure of device with technical specifications is resented. As a part of the investigation the prototype was built and series of experiments conducted. System parameter was measured, on this basis specification of elements for the final device were chosen. First stage of the project was successful. It was possible to efficiently generate seismic waves with constructed device. Then the field test was conducted. Spark gap wasplaced in shallowborehole(0.5 m) filled with salt water. Geophones were placed on the ground in straight line. The comparison of signal registered with hammer source and sparker source was made. The results of the test measurements are presented and discussed. Analysis of the collected data shows that characteristic of generated seismic signal is very promising, thus confirms possibility of practical application of the new high voltage generator. The biggest advantage of presented device after signal characteristics is its size which is 0.5 x 0.25 x 0.2 m and weight approximately 7 kg. This features with small li-ion battery makes

  5. High voltage pulse generator

    DOEpatents

    Fasching, George E.

    1977-03-08

    An improved high-voltage pulse generator has been provided which is especially useful in ultrasonic testing of rock core samples. An N number of capacitors are charged in parallel to V volts and at the proper instance are coupled in series to produce a high-voltage pulse of N times V volts. Rapid switching of the capacitors from the paralleled charging configuration to the series discharging configuration is accomplished by using silicon-controlled rectifiers which are chain self-triggered following the initial triggering of a first one of the rectifiers connected between the first and second of the plurality of charging capacitors. A timing and triggering circuit is provided to properly synchronize triggering pulses to the first SCR at a time when the charging voltage is not being applied to the parallel-connected charging capacitors. Alternate circuits are provided for controlling the application of the charging voltage from a charging circuit to be applied to the parallel capacitors which provides a selection of at least two different intervals in which the charging voltage is turned "off" to allow the SCR's connecting the capacitors in series to turn "off" before recharging begins. The high-voltage pulse-generating circuit including the N capacitors and corresponding SCR's which connect the capacitors in series when triggered "on" further includes diodes and series-connected inductors between the parallel-connected charging capacitors which allow sufficiently fast charging of the capacitors for a high pulse repetition rate and yet allow considerable control of the decay time of the high-voltage pulses from the pulse-generating circuit.

  6. START High Performance Discharges

    NASA Astrophysics Data System (ADS)

    Gates, D. A.

    1997-11-01

    Improvements to START (Small Tight Aspect Ratio Tokamak), the first spherical tokamak in the world to achieve high plasma temperature with both a significant pulse length and confinement time, have been ongoing since 1991. Recent modifications include: expansion of the existing capacitor banks allowing plasma currents as high as 300kA, an increase in the available neutral beam heating power ( ~ 500kW), and improvements to the vacuum system. These improvements have led to the achievement of the world record plasma β (≡ 2μ_0 /B^2) of ~ 30% in a tokamak. The normalised β ( βN ≡ β aB/I_p) reached 4.5 with q_95 = 2.3. Properties of the reconstructed equilibrium will be discussed in detail. The theoretical limit to β is higher in a spherical tokamak than in a conventional machine, due to the higher values of normalised current (IN ≡ I_p/aB) achievable at low aspect ratio. The record β was achieved with IN ~ 8 while conventional tokamaks are limited to IN ~ 3, or less. Calculations of the ideal MHD stability of the record discharge indicate high β low-n kink modes are stable, but that the entire profile is at or near marginal stability for high-n ballooning modes. The phenomenology of the events leading up to the plasma termination is discussed. An important aspect of the START program is to explore the physics of neutral beam absorption at low aspect ratio. A passive neutral particle analyser has been used to study the temporal and spatial dependence of the fast hydrogen beam ions. These measurements have been used in conjunction with a single particle orbit code to estimate the fast ion losses due to collisions with slow neutrals from the plasma edge. Numerical analysis of neutral beam power deposition profiles are compared with the data from an instrumented beam stop. The global energy confinement time τE in beam heated discharges on START is similar to that obtained in Ohmic discharges, even though the input power has roughly doubled over the Ohmic case

  7. High resolution analysis

    NASA Technical Reports Server (NTRS)

    Robinove, C. J.

    1982-01-01

    The possibilities for the use of high spectral resolution analysis in the field of hydrology and water resources are examined. Critical gaps in scientific knowledge that must be filled before technology can be evaluated involve the spectral response of water, substances dissolved and suspended in water, and substances floating on water. The most complete mapping of oil slicks can be done in the ultraviolet region. A mean of measuring the ultraviolet reflection at the surface from satellite altitudes needs to be determined. The use of high spectral resolution sensors in a reasonable number of narrow bands may be able to sense the reflectance or emission characteristics of water and its contained materials that can be correlated with commonly used water quality variables. Technological alternative available to experiment with problems of sensing water quality are to use existing remote sensing instrumentation in an empirical mode and to develop instruments for either testing hypoteses or conducting empirical experiments.

  8. High energy beam lines

    NASA Astrophysics Data System (ADS)

    Marchetto, M.; Laxdal, R. E.

    2014-01-01

    The ISAC post accelerator comprises an RFQ, DTL and SC-linac. The high energy beam lines connect the linear accelerators as well as deliver the accelerated beams to two different experimental areas. The medium energy beam transport (MEBT) line connects the RFQ to the DTL. The high energy beam transport (HEBT) line connects the DTL to the ISAC-I experimental stations (DRAGON, TUDA-I, GPS). The DTL to superconducting beam (DSB) transport line connects the ISAC-I and ISAC-II linacs. The superconducting energy beam transport (SEBT) line connects the SC linac to the ISAC-II experimental station (TUDA-II, HERACLES, TIGRESS, EMMA and GPS). All these lines have the function of transporting and matching the beams to the downstream sections by manipulating the transverse and longitudinal phase space. They also contain diagnostic devices to measure the beam properties.

  9. High Efficiency Cell Development

    NASA Technical Reports Server (NTRS)

    Carbajal, B. G.

    1979-01-01

    The specific activity was to improve the tandem junction Cell (TJC) as a high efficiency solar cell. The TJC development was to be consistent with module assembly and should contribute to the overall goals of the Low-Cost Solar Array Project. During 1978, TJC efficiency improved from approximately 11 percent to approximately 16 percent (AMI). Photogenerated current densities in excess of 42 mA/sq cm were observed at AMO. Open circuit voltages as high as 0.615 V were measured at AMO. Fill factor was only 0.68 - 0.75 due to a nonoptimum metal contact design. A device model was conceived in which the solar cell is modelled as a transitor. There are virtually no interconnect or packaging factor systems and the TJC is compatible with all conventional module fabrication systems. A modification of the TJC, the Front Surface Field (FSF) cell, was also explored.

  10. Prospects at high energies

    SciTech Connect

    Quigg, C.

    1988-11-01

    I discuss some possibilities for neutrino experiments in the fixed-target environment of the SPS, Tevatron, and UNK, with their primary proton beams of 0.4, 0.9, and 3.0 TeV. The emphasis is on unfinished business: issues that have been recognized for some time, but not yet resolved. Then I turn to prospects for proton-proton colliders to explore the 1-TeV scale. I review the motivation for new physics in the neighborhood of 1 TeV and mention some discovery possibilities for high-energy, high-luminosity hadron colliders and the implications they would have for neutrino physics. I raise the possibility of the direct study of neutrino interactions in hadron colliders. I close with a report on the status of the SSC project. 38 refs., 17 figs.

  11. High Latitude Polygons

    NASA Technical Reports Server (NTRS)

    2005-01-01

    26 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows polygonal patterned ground on a south high-latitude plain. The outlines of the polygons, like the craters and hills in this region, are somewhat enhanced by the presence of bright frost left over from the previous winter. On Earth, polygons at high latitudes would usually be attributed to the seasonal freezing and thawing cycles of ground ice. The origin of similar polygons on Mars is less certain, but might also be an indicator of ground ice.

    Location near: 75.3oS, 113.2oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  12. High temperature future

    SciTech Connect

    Sheinkopf, K.

    1994-09-01

    During the past few years, there have been dramatic accomplishments and success of high temperature solar thermal systems and significant development of these systems. High temperature technologies, about 500 F and higher, such as dish engines, troughs, central receiver power towers and solar process heat systems, have been tested, demonstrated and used in an array of applications, including many cost-effective utility bulk power production and demand side supply projects in the United States. Large systems provide power and hot water to prisons, schools, nursing homes and other institutions. Joint ventures with industry, utility projects, laboratory design assistance and other activities are building a solid industry of US solar thermal systems ready for use today.

  13. [High frequency ultrasound].

    PubMed

    Sattler, E

    2015-07-01

    Diagnostic ultrasound has become a standard procedure in clinical dermatology. Devices with intermediate high frequencies of 7.5-15 MHz are used in dermato-oncology for the staging and postoperative care of skin tumor patients and in angiology for improved vessel diagnostics. In contrast, the high frequency ultrasound systems with 20-100 MHz probes offer a much higher resolution, yet with a lower penetration depth of about 1 cm. The main indications are the preoperative measurements of tumor thickness in malignant melanoma and other skin tumors and the assessment of inflammatory and soft tissue diseases, offering information on the course of these dermatoses and allowing therapy monitoring. This article gives an overview on technical principles, devices, mode of examination, influencing factors, interpretation of the images, indications but also limitations of this technique. PMID:25636803

  14. High temperature probe

    DOEpatents

    Swan, Raymond A.

    1994-01-01

    A high temperature probe for sampling, for example, smokestack fumes, and is able to withstand temperatures of 3000.degree. F. The probe is constructed so as to prevent leakage via the seal by placing the seal inside the water jacket whereby the seal is not exposed to high temperature, which destroys the seal. The sample inlet of the probe is also provided with cooling fins about the area of the seal to provide additional cooling to prevent the seal from being destroyed. Also, a heated jacket is provided for maintaining the temperature of the gas being tested as it passes through the probe. The probe includes pressure sensing means for determining the flow velocity of an efficient being sampled. In addition, thermocouples are located in various places on the probe to monitor the temperature of the gas passing there through.

  15. High temperature measuring device

    DOEpatents

    Tokarz, Richard D.

    1983-01-01

    A temperature measuring device for very high design temperatures (to 2,000.degree. C.). The device comprises a homogenous base structure preferably in the form of a sphere or cylinder. The base structure contains a large number of individual walled cells. The base structure has a decreasing coefficient of elasticity within the temperature range being monitored. A predetermined quantity of inert gas is confined within each cell. The cells are dimensionally stable at the normal working temperature of the device. Increases in gaseous pressure within the cells will permanently deform the cell walls at temperatures within the high temperature range to be measured. Such deformation can be correlated to temperature by calibrating similarly constructed devices under known time and temperature conditions.

  16. High energy from space

    NASA Technical Reports Server (NTRS)

    Margon, Bruce; Canizares, Claude; Catura, Richard C.; Clark, George W.; Fichtel, Carl E.; Friedman, Herbert; Giacconi, Riccardo; Grindlay, Jonathan E.; Helfand, David J.; Holt, Stephen S.

    1991-01-01

    The following subject areas are covered: (1) important scientific problems for high energy astrophysics (stellar activity, the interstellar medium in galaxies, supernovae and endpoints of stellar evolution, nucleosynthesis, relativistic plasmas and matter under extreme conditions, nature of gamma-bursts, identification of black holes, active nuclei, accretion physics, large-scale structures, intracluster medium, nature of dark matter, and the X- and gamma-ray background); (2) the existing experimental programs (Advanced X-Ray Astrophysics Facility (AXAF), Gamma Ray Observatory (GRO), X-Ray Timing Explorer (XTE), High Energy Transient Experiment (HETE), U.S. participation in foreign missions, and attached Shuttle and Space Station Freedom payloads); (3) major missions for the 1990's; (4) a new program of moderate missions; (5) new opportunities for small missions; (6) technology development issues; and (7) policy issues.

  17. High temperature structural silicides

    SciTech Connect

    Petrovic, J.J.

    1997-03-01

    Structural silicides have important high temperature applications in oxidizing and aggressive environments. Most prominent are MoSi{sub 2}-based materials, which are borderline ceramic-intermetallic compounds. MoSi{sub 2} single crystals exhibit macroscopic compressive ductility at temperatures below room temperature in some orientations. Polycrystalline MoSi{sub 2} possesses elevated temperature creep behavior which is highly sensitive to grain size. MoSi{sub 2}-Si{sub 3}N{sub 4} composites show an important combination of oxidation resistance, creep resistance, and low temperature fracture toughness. Current potential applications of MoSi{sub 2}-based materials include furnace heating elements, molten metal lances, industrial gas burners, aerospace turbine engine components, diesel engine glow plugs, and materials for glass processing.

  18. Highly directional acoustic receivers.

    PubMed

    Cray, Benjamin A; Evora, Victor M; Nuttall, Albert H

    2003-03-01

    The theoretical directivity of a single combined acoustic receiver, a device that can measure many quantities of an acoustic field at a collocated point, is presented here. The formulation is developed using a Taylor series expansion of acoustic pressure about the origin of a Cartesian coordinate system. For example, the quantities measured by a second-order combined receiver, denoted a dyadic sensor, are acoustic pressure, the three orthogonal components of acoustic particle velocity, and the nine spatial gradients of the velocity vector. The power series expansion, which can be of any order, is cast into an expression that defines the directivity of a single receiving element. It is shown that a single highly directional dyadic sensor can have a directivity index of up to 9.5 dB. However, there is a price to pay with highly directive sensors; these sensors can be significantly more sensitive to nonacoustic noise sources. PMID:12656387

  19. High voltage isolation transformer

    NASA Technical Reports Server (NTRS)

    Clatterbuck, C. H.; Ruitberg, A. P. (Inventor)

    1985-01-01

    A high voltage isolation transformer is provided with primary and secondary coils separated by discrete electrostatic shields from the surfaces of insulating spools on which the coils are wound. The electrostatic shields are formed by coatings of a compound with a low electrical conductivity which completely encase the coils and adhere to the surfaces of the insulating spools adjacent to the coils. Coatings of the compound also line axial bores of the spools, thereby forming electrostatic shields separating the spools from legs of a ferromagnetic core extending through the bores. The transformer is able to isolate a high constant potential applied to one of its coils, without the occurrence of sparking or corona, by coupling the coatings, lining the axial bores to the ferromagnetic core and by coupling one terminal of each coil to the respective coating encasing the coil.

  20. High frequency reference electrode

    DOEpatents

    Kronberg, J.W.

    1994-05-31

    A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or halo' at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes. 4 figs.

  1. High Temperature Thermosets

    NASA Technical Reports Server (NTRS)

    Hergenrother, Paul M.

    1999-01-01

    A thermoset or network polymer is an organic material where the molecules are tied together through chemical bonds (crosslinks) and therefore they cannot move past one another. As a result, these materials exhibit a certain degree of dimensional stability. The chemical composition and the degree of crosslink density of the thermoset have a pronounced effect upon the properties. High temperature thermosets offer a favorable combination of properties that makes them attractive for many applications. Their most important features are the excellent processability particularly of the low molecular weight precusor forms, the chemical and solvent resistance and the dimensional stability. The market for high temperature thermosets will increase as new uses for them are uncovered and new thermosets with better combinations of properties are developed.

  2. High Temperature ESP Monitoring

    SciTech Connect

    Jack Booker; Brindesh Dhruva

    2011-06-20

    The objective of the High Temperature ESP Monitoring project was to develop a downhole monitoring system to be used in wells with bottom hole well temperatures up to 300°C for measuring motor temperature, formation pressure, and formation temperature. These measurements are used to monitor the health of the ESP motor, to track the downhole operating conditions, and to optimize the pump operation. A 220 ºC based High Temperature ESP Monitoring system was commercially released for sale with Schlumberger ESP motors April of 2011 and a 250 ºC system with will be commercially released at the end of Q2 2011. The measurement system is now fully qualified, except for the sensor, at 300 °C.

  3. High frequency reference electrode

    DOEpatents

    Kronberg, James W.

    1994-01-01

    A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or "halo" at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes.

  4. High energy transients

    NASA Technical Reports Server (NTRS)

    Woosley, S. E.

    1984-01-01

    A meeting was convened on the campus of the University of California at Santa Cruz during the two-week interval July 11 through July 22, 1983. Roughly 100 participants were chosen so as to give broad representation to all aspects of high energy transients. Ten morning review sessions were held in which invited speakers discussed the current status of observations and theory of the above subjects. Afternoon workshops were also held, usually more than one per day, to informally review various technical aspects of transients, confront shortcomings in theoretical models, and to propose productive courses for future research. Special attention was also given to the instrumentation used to study high energy transient and the characteristics and goals of a dedicated space mission to study transients in the next decade were determined. A listing of articles written by various members of the workshop is included.

  5. High voltage pulse conditioning

    DOEpatents

    Springfield, Ray M.; Wheat, Jr., Robert M.

    1990-01-01

    Apparatus for conditioning high voltage pulses from particle accelerators in order to shorten the rise times of the pulses. Flashover switches in the cathode stalk of the transmission line hold off conduction for a determinable period of time, reflecting the early portion of the pulses. Diodes upstream of the switches divert energy into the magnetic and electrostatic storage of the capacitance and inductance inherent to the transmission line until the switches close.

  6. Insulators for high voltages

    SciTech Connect

    Looms, J.S.T.

    1987-01-01

    This book describes electrical insulators for high voltage applications. Topics considered include the insulating materials, the manufacture of wet process porcelain, the manufacture of tempered glass, the glass-fibre core, the polymeric housing, the common problem - terminating an insulator, mechanical constraints, the physics of pollution flashover, the physics of contamination, testing of insulators, conclusions from testing, remedies for flashover, insulators for special cases, interference and noise, and the insulator of the future.

  7. High speed door assembly

    SciTech Connect

    Shapiro, C.

    1991-12-31

    This invention is comprised of a high speed door assembly, comprising an actuator cylinder and piston rods, a pressure supply cylinder and fittings, an electrically detonated explosive bolt, a honeycomb structured door, a honeycomb structured decelerator, and a structural steel frame encasing the assembly to close over a 3 foot diameter opening within 50 milliseconds of actuation, to contain hazardous materials and vapors within a test fixture.

  8. High density circuit technology

    NASA Technical Reports Server (NTRS)

    Wade, T. E.

    1979-01-01

    Polyimide dielectric materials were acquired for comparative and evaluative studies in double layer metal processes. Preliminary experiments were performed. Also, the literature indicates that sputtered aluminum films may be successfully patterned using the left-off technique provided the substrate temperature remains low and the argon pressure in the chamber is relatively high at the time of sputtering. Vendors associated with dry processing equipment are identified. A literature search relative to future trends in VLSI fabrication techniques is described.

  9. Ultra high resolution tomography

    SciTech Connect

    Haddad, W.S.

    1994-11-15

    Recent work and results on ultra high resolution three dimensional imaging with soft x-rays will be presented. This work is aimed at determining microscopic three dimensional structure of biological and material specimens. Three dimensional reconstructed images of a microscopic test object will be presented; the reconstruction has a resolution on the order of 1000 A in all three dimensions. Preliminary work with biological samples will also be shown, and the experimental and numerical methods used will be discussed.

  10. High Temperature Structural Foam

    NASA Technical Reports Server (NTRS)

    Weiser, Erik S.; Baillif, Faye F.; Grimsley, Brian W.; Marchello, Joseph M.

    1997-01-01

    The Aerospace Industry is experiencing growing demand for high performance polymer foam. The X-33 program needs structural foam insulation capable of retaining its strength over a wide range of environmental conditions. The High Speed Research Program has a need for low density core splice and potting materials. This paper reviews the state of the art in foam materials and describes experimental work to fabricate low density, high shear strength foam which can withstand temperatures from -220 C to 220 C. Commercially available polymer foams exhibit a wide range of physical properties. Some with densities as low as 0.066 g/cc are capable of co-curing at temperatures as high as 182 C. Rohacell foams can be resin transfer molded at temperatures up to 180 C. They have moduli of elasticity of 0.19 MPa, tensile strengths of 3.7 Mpa and compressive strengths of 3.6 MPa. The Rohacell foams cannot withstand liquid hydrogen temperatures, however Imi-Tech markets Solimide (trademark) foams which withstand temperatures from -250 C to 200 C, but they do not have the required structural integrity. The research activity at NASA Langley Research Center focuses on using chemical blowing agents to produce polyimide thermoplastic foams capable of meeting the above performance requirements. The combination of blowing agents that decompose at the minimum melt viscosity temperature together with plasticizers to lower the viscosity has been used to produce foams by both extrusion and oven heating. The foams produced exhibit good environmental stability while maintaining structural properties.