Science.gov

Sample records for absorption gsa system

  1. a Gsa-Svm Hybrid System for Classification of Binary Problems

    NASA Astrophysics Data System (ADS)

    Sarafrazi, Soroor; Nezamabadi-pour, Hossein; Barahman, Mojgan

    2011-06-01

    This paperhybridizesgravitational search algorithm (GSA) with support vector machine (SVM) and made a novel GSA-SVM hybrid system to improve the classification accuracy in binary problems. GSA is an optimization heuristic toolused to optimize the value of SVM kernel parameter (in this paper, radial basis function (RBF) is chosen as the kernel function). The experimental results show that this newapproach can achieve high classification accuracy and is comparable to or better than the particle swarm optimization (PSO)-SVM and genetic algorithm (GA)-SVM, which are two hybrid systems for classification.

  2. GSA-Tuning IPD Control of a Field-Sensed Magnetic Suspension System

    PubMed Central

    Li, Jen-Hsing; Chiou, Juing-Shian

    2015-01-01

    The purpose of this paper is to propose a GSA-tuning IPD control technique for magnetic suspension systems. An educational demonstration on a magnetic-field sensed magnetic suspension system is examined for effectiveness. For the magnetic-field sensed magnetic suspension system (FSMSS), the current transducer is employed for measuring the electromagnetic coil current, and a Hall effect device is used for detecting the position of the suspended object. To achieve optimal performance, the gravitational search algorithm (GSA) is adopted for tuning the integral-proportional-derivative (IPD) controller. The IPD control includes the specified PD controller and an integrator. The specified PD control is employed for stabilizing the inherently unstable FSMSS, whereas the integral control is utilized for eliminating the steady-state error. The GSA can tune the IPD control parameters to enable optimal FSMSS performance. We achieved excellent results from the simulations and hands-on experiments for the proposed control strategies and structures. PMID:26694404

  3. 41 CFR 105-64.106 - What is GSA's policy on information accuracy in a system of records?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Responsibilities § 105-64.106 What is GSA's policy on information accuracy in a system of records? System managers... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What is GSA's policy on information accuracy in a system of records? 105-64.106 Section 105-64.106 Public Contracts and...

  4. 41 CFR 105-64.103 - What is GSA's policy on collecting and using information in a system of records?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Responsibilities § 105-64.103 What is GSA's policy on collecting and using information in a system of records... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What is GSA's policy on collecting and using information in a system of records? 105-64.103 Section 105-64.103 Public Contracts...

  5. 41 CFR 105-64.102 - What is GSA's policy on disclosure of information in a system of records?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Responsibilities § 105-64.102 What is GSA's policy on disclosure of information in a system of records? No... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What is GSA's policy on disclosure of information in a system of records? 105-64.102 Section 105-64.102 Public Contracts and...

  6. 41 CFR 102-118.170 - Will GSA continue to maintain a centralized numbering system for Government transportation...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Will GSA continue to maintain a centralized numbering system for Government transportation documents? 102-118.170 Section 102... centralized numbering system for Government transportation documents? Yes, GSA will maintain a...

  7. 41 CFR 102-118.170 - Will GSA continue to maintain a centralized numbering system for Government transportation...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Will GSA continue to maintain a centralized numbering system for Government transportation documents? 102-118.170 Section 102... centralized numbering system for Government transportation documents? Yes, GSA will maintain a...

  8. 41 CFR 102-118.170 - Will GSA continue to maintain a centralized numbering system for Government transportation...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Will GSA continue to maintain a centralized numbering system for Government transportation documents? 102-118.170 Section 102... centralized numbering system for Government transportation documents? Yes, GSA will maintain a...

  9. 41 CFR 102-118.170 - Will GSA continue to maintain a centralized numbering system for Government transportation...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Will GSA continue to maintain a centralized numbering system for Government transportation documents? 102-118.170 Section 102... centralized numbering system for Government transportation documents? Yes, GSA will maintain a...

  10. 41 CFR 102-118.170 - Will GSA continue to maintain a centralized numbering system for Government transportation...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... maintain a centralized numbering system for Government transportation documents? 102-118.170 Section 102-118.170 Public Contracts and Property Management Federal Property Management Regulations System... centralized numbering system for Government transportation documents? Yes, GSA will maintain a...

  11. Zone Level Occupant-Responsive Building Energy Systems at the GSA

    SciTech Connect

    Robinson, Alastair

    2014-03-01

    The General Services Administration (GSA) partnered with the U.S. Department of Energy (DOE) to develop and implement building energy system retrofits, aiming to reduce energy consumption of at least two building systems by a total of 30 percent or more, as part of DOE’s Commercial Building Partnership (CBP) Program. Lawrence Berkeley National Laboratory (LBNL) provided technical expertise in support of this DOE program, working with the GSA and a team of consultants. This case study reports expected energy savings from appropriate energy efficient design and operations modifications to lighting and heating, ventilating and air conditioning (HVAC) systems at the selected study sites. These retrofits comprised installation of new lighting systems with dimming capability and occupancy-sensor control at the individual light fixture level, and utilized lighting system occupancy sensor signals to continually readjust zone-level ventilation airflow according to the number of people present, down to minimum rates when vacant.

  12. 41 CFR 101-30.603 - GSA Supply Catalog.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false GSA Supply Catalog. 101... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.6-GSA Section of the Federal Supply Catalog § 101-30.603 GSA Supply Catalog. (a) The GSA...

  13. 41 CFR 101-30.603 - GSA Supply Catalog.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true GSA Supply Catalog. 101... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.6-GSA Section of the Federal Supply Catalog § 101-30.603 GSA Supply Catalog. (a) The GSA...

  14. 41 CFR 101-30.603-2 - GSA Supply Catalog.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true GSA Supply Catalog. 101... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.6-GSA Section of the Federal Supply Catalog § 101-30.603-2 GSA Supply Catalog. The GSA...

  15. 41 CFR 101-30.603-2 - GSA Supply Catalog.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true GSA Supply Catalog. 101... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.6-GSA Section of the Federal Supply Catalog § 101-30.603-2 GSA Supply Catalog. The GSA...

  16. 41 CFR 101-30.603 - GSA Supply Catalog.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 2 2011-07-01 2007-07-01 true GSA Supply Catalog. 101... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.6-GSA Section of the Federal Supply Catalog § 101-30.603 GSA Supply Catalog. (a) The GSA...

  17. 41 CFR 101-30.603-2 - GSA Supply Catalog.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 2 2011-07-01 2007-07-01 true GSA Supply Catalog. 101... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.6-GSA Section of the Federal Supply Catalog § 101-30.603-2 GSA Supply Catalog. The GSA...

  18. 41 CFR 101-30.603 - GSA Supply Catalog.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true GSA Supply Catalog. 101... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.6-GSA Section of the Federal Supply Catalog § 101-30.603 GSA Supply Catalog. (a) The GSA...

  19. 41 CFR 101-30.603-2 - GSA Supply Catalog.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false GSA Supply Catalog. 101... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.6-GSA Section of the Federal Supply Catalog § 101-30.603-2 GSA Supply Catalog. The GSA...

  20. 41 CFR 101-30.603-2 - GSA Supply Catalog.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true GSA Supply Catalog. 101... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.6-GSA Section of the Federal Supply Catalog § 101-30.603-2 GSA Supply Catalog. The GSA...

  1. 41 CFR 101-30.603 - GSA Supply Catalog.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true GSA Supply Catalog. 101... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.6-GSA Section of the Federal Supply Catalog § 101-30.603 GSA Supply Catalog. (a) The GSA...

  2. Absorption heat pump system

    DOEpatents

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  3. Absorption heat pump system

    DOEpatents

    Grossman, Gershon

    1984-01-01

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  4. Optical absorption measurement system

    DOEpatents

    Draggoo, Vaughn G.; Morton, Richard G.; Sawicki, Richard H.; Bissinger, Horst D.

    1989-01-01

    The system of the present invention contemplates a non-intrusive method for measuring the temperature rise of optical elements under high laser power optical loading to determine the absorption coefficient. The method comprises irradiating the optical element with a high average power laser beam, viewing the optical element with an infrared camera to determine the temperature across the optical element and calculating the absorption of the optical element from the temperature.

  5. Absorption heat pump system

    DOEpatents

    Grossman, Gershon; Perez-Blanco, Horacio

    1984-01-01

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  6. Solar-energy-system performance evaluation update: GSA/Federal Youth Center, Bastrop, Texas, October 1982-April 1983

    SciTech Connect

    Logee, T.L.

    1983-01-01

    This report is the second in a series of performance evaluation reports on the GSA/Federal Youth Center located in Bastrop, Texas. The GSA/Federal Youth Center is a federal correctional institute for youthful, male offenders in Bastrop, Texas. The active solar energy system is equipped with: 21,760 square feet of single-glazed, liquid flat-plate collectors manufactured by Cole Solar Systems. The storage consists of 40,000 gallons of insulated outdoor water tanks. Two 100-horsepower boilers and one 30-horsepower boiler burning natural gas with the capability to use Number 2 diesel fuel make up the auxiliary system. Solar energy is used to supply the hot water and space heating loads of the dormitory, offices, cafeteria, and hospital. During the summer, solar energy can also be used to supply some of the cooling load. The solar energy system at this Federal Correctional Institute operated well from October 1982 through April 1983. The solar system provided an estimated 12% or 866 million of the estimated total load of 7600 million Btu. There were 10 days of downtime in April caused by a failure of the collector pump. However, the collector pump high-speed motor had started to fail earlier in November. There were no other unusual solar system maintenance requirements during this period. The system performance during the monitoring period was 39% of the expected annual design performance, based on a proportional number of months.

  7. Support and Dissemination of Teacher-Authored Lesson Plans: a Digital Library for Earth System Education (DLESE) and Geological Society of America (GSA) Collaboration

    NASA Astrophysics Data System (ADS)

    Devaul, H.; Pandya, R. E.; McLelland, C. V.

    2003-12-01

    The Digital Library for Earth System Education (www.dlese.org) and the Geological Society of America (www.geosociety.org) are working together to publish and disseminate teacher-authored Earth science lesson plans. DLESE is a community-based effort involving teachers, students, and scientists working together to create a library of educational resources and services to support Earth system science education. DLESE offers free access to electronic resources including lesson plans, maps, images, data sets, visualizations, and assessment activities. A number of thematic collections have recently been accessioned, which has substantially increased library holdings. Working in concert with GSA, a non-profit organization dedicated to the advancement of the geosciences, small-scale resource creators such as classroom teachers without access to a web server can also share educational resources of their own design. Following a two-step process, lesson plans are submitted to the GSA website, reviewed and posted to the K-12 resource area: http://www.geosociety.org/educate/resources.htm. These resources are also submitted to the DLESE Community Collection using a simple cataloging tool. In this way resources are available to other teachers via the GSA website as well as via the DLESE collection. GSA provides a template for lesson plan developers which assists in providing the necessary information to help users find and understand the intent of the activity when searching in DLESE. This initial effort can serve as a prototype for important services allowing individual community members to contribute their work to DLESE with little technical overhead.

  8. 41 CFR 105-64.106 - What is GSA's policy on information accuracy in a system of records?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Regional Offices-General Services Administration 64-GSA PRIVACY ACT RULES 64.1-Policies and... will ensure that all Privacy Act records are accurate, relevant, necessary, timely, and complete. All...) are reviewed to ensure they are relevant, necessary, accurate, up-to-date, and covered by...

  9. 41 CFR 105-64.106 - What is GSA's policy on information accuracy in a system of records?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Regional Offices-General Services Administration 64-GSA PRIVACY ACT RULES 64.1-Policies and... will ensure that all Privacy Act records are accurate, relevant, necessary, timely, and complete. All...) are reviewed to ensure they are relevant, necessary, accurate, up-to-date, and covered by...

  10. Absorption-heat-pump system

    DOEpatents

    Grossman, G.; Perez-Blanco, H.

    1983-06-16

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  11. 41 CFR 101-1.4902-2053 - GSA Form 2053, Agency Consolidated Requirements for GSA Regulations and Other External Issuances.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-2053 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS GENERAL 1-INTRODUCTION 1.49-Illustrations of Forms § 101-1.4902-2053 GSA... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true GSA Form 2053,...

  12. 41 CFR 101-30.101-10 - GSA section of the Federal Supply Catalog.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Federal Supply Catalog. 101-30.101-10 Section 101-30.101-10 Public Contracts and Property Management... PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.1-General § 101-30.101-10 GSA section of the Federal Supply Catalog. GSA section of the Federal Supply Catalog means a series of supply catalogs issued by GSA as...

  13. 41 CFR 101-30.101-10 - GSA section of the Federal Supply Catalog.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Federal Supply Catalog. 101-30.101-10 Section 101-30.101-10 Public Contracts and Property Management... PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.1-General § 101-30.101-10 GSA section of the Federal Supply Catalog. GSA section of the Federal Supply Catalog means a series of supply catalogs issued by GSA as...

  14. 41 CFR 101-30.101-10 - GSA section of the Federal Supply Catalog.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Federal Supply Catalog. 101-30.101-10 Section 101-30.101-10 Public Contracts and Property Management... PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.1-General § 101-30.101-10 GSA section of the Federal Supply Catalog. GSA section of the Federal Supply Catalog means a series of supply catalogs issued by GSA as...

  15. 41 CFR 101-30.101-10 - GSA section of the Federal Supply Catalog.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Federal Supply Catalog. 101-30.101-10 Section 101-30.101-10 Public Contracts and Property Management... PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.1-General § 101-30.101-10 GSA section of the Federal Supply Catalog. GSA section of the Federal Supply Catalog means a series of supply catalogs issued by GSA as...

  16. 41 CFR 101-30.101-10 - GSA section of the Federal Supply Catalog.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Federal Supply Catalog. 101-30.101-10 Section 101-30.101-10 Public Contracts and Property Management... PROCUREMENT 30-FEDERAL CATALOG SYSTEM 30.1-General § 101-30.101-10 GSA section of the Federal Supply Catalog. GSA section of the Federal Supply Catalog means a series of supply catalogs issued by GSA as...

  17. Adaptive GSA-based optimal tuning of PI controlled servo systems with reduced process parametric sensitivity, robust stability and controller robustness.

    PubMed

    Precup, Radu-Emil; David, Radu-Codrut; Petriu, Emil M; Radac, Mircea-Bogdan; Preitl, Stefan

    2014-11-01

    This paper suggests a new generation of optimal PI controllers for a class of servo systems characterized by saturation and dead zone static nonlinearities and second-order models with an integral component. The objective functions are expressed as the integral of time multiplied by absolute error plus the weighted sum of the integrals of output sensitivity functions of the state sensitivity models with respect to two process parametric variations. The PI controller tuning conditions applied to a simplified linear process model involve a single design parameter specific to the extended symmetrical optimum (ESO) method which offers the desired tradeoff to several control system performance indices. An original back-calculation and tracking anti-windup scheme is proposed in order to prevent the integrator wind-up and to compensate for the dead zone nonlinearity of the process. The minimization of the objective functions is carried out in the framework of optimization problems with inequality constraints which guarantee the robust stability with respect to the process parametric variations and the controller robustness. An adaptive gravitational search algorithm (GSA) solves the optimization problems focused on the optimal tuning of the design parameter specific to the ESO method and of the anti-windup tracking gain. A tuning method for PI controllers is proposed as an efficient approach to the design of resilient control systems. The tuning method and the PI controllers are experimentally validated by the adaptive GSA-based tuning of PI controllers for the angular position control of a laboratory servo system. PMID:25330468

  18. Landing gear energy absorption system

    NASA Technical Reports Server (NTRS)

    Hansen, Christopher P. (Inventor)

    1994-01-01

    A landing pad system is described for absorbing horizontal and vertical impact forces upon engagement with a landing surface where circumferentially arranged landing struts respectively have a clevis which receives a slidable rod member and where the upper portion of a slidable rod member is coupled to the clevis by friction washers which are force fit onto the rod member to provide for controlled constant force energy absorption when the rod member moves relative to the clevis. The lower end of the friction rod is pivotally attached by a ball and socket to a support plate where the support plate is arranged to slide in a transverse direction relative to a housing which contains an energy absorption material for absorbing energy in a transverse direction.

  19. Backscatter absorption gas imaging system

    DOEpatents

    McRae, T.G. Jr.

    A video imaging system for detecting hazardous gas leaks. Visual displays of invisible gas clouds are produced by radiation augmentation of the field of view of an imaging device by radiation corresponding to an absorption line of the gas to be detected. The field of view of an imager is irradiated by a laser. The imager receives both backscattered laser light and background radiation. When a detectable gas is present, the backscattered laser light is highly attenuated, producing a region of contrast or shadow on the image. A flying spot imaging system is utilized to synchronously irradiate and scan the area to lower laser power requirements. The imager signal is processed to produce a video display.

  20. Backscatter absorption gas imaging system

    DOEpatents

    McRae, Jr., Thomas G.

    1985-01-01

    A video imaging system for detecting hazardous gas leaks. Visual displays of invisible gas clouds are produced by radiation augmentation of the field of view of an imaging device by radiation corresponding to an absorption line of the gas to be detected. The field of view of an imager is irradiated by a laser. The imager receives both backscattered laser light and background radiation. When a detectable gas is present, the backscattered laser light is highly attenuated, producing a region of contrast or shadow on the image. A flying spot imaging system is utilized to synchronously irradiate and scan the area to lower laser power requirements. The imager signal is processed to produce a video display.

  1. Clean Coal Technology III: 10 MW Demonstration of Gas Suspension Absorption final project performance and economics report

    SciTech Connect

    Hsu, F.E.

    1995-08-01

    The 10 MW Demonstration of the Gas Suspension Absorption (GSA) program is a government and industry co-funded technology development. The objective of the project is to demonstrate the performance of the GSA system in treating a 10 MW slipstream of flue gas resulting from the combustion of a high sulfur coal. This project involves design, fabrication, construction and testing of the GSA system. The Project Performance and Economics Report provides the nonproprietary information for the ``10 MW Demonstration of the Gas Suspension Absorption (GSA) Project`` installed at Tennessee Valley Authority`s (TVA) Shawnee Power Station, Center for Emissions Research (CER) at Paducah, Kentucky. The program demonstrated that the GSA flue-gas-desulfurization (FGD) technology is capable of achieving high SO{sub 2} removal efficiencies (greater than 90%), while maintaining particulate emissions below the New Source Performance Standards (NSPS), without any negative environmental impact (section 6). A 28-day test demonstrated the reliability and operability of the GSA system during continuous operation. The test results and detailed discussions of the test data can be obtained from TVA`s Final Report (Appendix A). The Air Toxics Report (Appendix B), prepared by Energy and Environmental Research Corporation (EERC) characterizes air toxic emissions of selected hazardous air pollutants (HAP) from the GSA process. The results of this testing show that the GSA system can substantially reduce the emission of these HAP. With its lower capital costs and maintenance costs (section 7), as compared to conventional semi-dry scrubbers, the GSA technology commands a high potential for further commercialization in the United States. For detailed information refer to The Economic Evaluation Report (Appendix C) prepared by Raytheon Engineers and Constructors.

  2. 41 CFR 105-64.110 - When may GSA establish computer matching programs?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... computer matching programs? 105-64.110 Section 105-64.110 Public Contracts and Property Management Federal... GSA establish computer matching programs? (a) System managers will establish computer matching... direction of the GSA Data Integrity Board that will be established when and if computer matching...

  3. 41 CFR 105-64.110 - When may GSA establish computer matching programs?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... computer matching programs? 105-64.110 Section 105-64.110 Public Contracts and Property Management Federal... GSA establish computer matching programs? (a) System managers will establish computer matching... direction of the GSA Data Integrity Board that will be established when and if computer matching...

  4. 41 CFR 105-64.110 - When may GSA establish computer matching programs?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... computer matching programs? 105-64.110 Section 105-64.110 Public Contracts and Property Management Federal... GSA establish computer matching programs? (a) System managers will establish computer matching... direction of the GSA Data Integrity Board that will be established when and if computer matching...

  5. 41 CFR 105-64.110 - When may GSA establish computer matching programs?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... computer matching programs? 105-64.110 Section 105-64.110 Public Contracts and Property Management Federal... GSA establish computer matching programs? (a) System managers will establish computer matching... direction of the GSA Data Integrity Board that will be established when and if computer matching...

  6. 41 CFR 105-64.110 - When may GSA establish computer matching programs?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... computer matching programs? 105-64.110 Section 105-64.110 Public Contracts and Property Management Federal... GSA establish computer matching programs? (a) System managers will establish computer matching... direction of the GSA Data Integrity Board that will be established when and if computer matching...

  7. The Clean Coal Technology Program 100 MWe demonstration of gas suspension absorption for flue gas desulfurization

    SciTech Connect

    Hsu, F.E.; Hedenhag, J.G.; Marchant, S.K.; Pukanic, G.W.; Norwood, V.M.; Burnett, T.A.

    1997-12-31

    AirPol Inc., with the cooperation of the Tennessee Valley Authority (TVA) under a Cooperative Agreement with the United States Department of Energy, installed and tested a 10 MWe Gas Suspension Absorption (GSA) Demonstration system at TVA`s Shawnee Fossil Plant near Paducah, Kentucky. This low-cost retrofit project demonstrated that the GSA system can remove more than 90% of the sulfur dioxide from high-sulfur coal-fired flue gas, while achieving a relatively high utilization of reagent lime. This paper presents a detailed technical description of the Clean Coal Technology demonstration project. Test results and data analysis from the preliminary testing, factorial tests, air toxics texts, 28-day continuous demonstration run of GSA/electrostatic precipitator (ESP), and 14-day continuous demonstration run of GSA/pulse jet baghouse (PJBH) are also discussed within this paper.

  8. Plasmon absorption modulator systems and methods

    DOEpatents

    Kekatpure, Rohan Deodatta; Davids, Paul

    2014-07-15

    Plasmon absorption modulator systems and methods are disclosed. A plasmon absorption modulator system includes a semiconductor substrate, a plurality of quantum well layers stacked on a top surface of the semiconductor substrate, and a metal layer formed on a top surface of the stack of quantum well layers. A method for modulating plasmonic current includes enabling propagation of the plasmonic current along a metal layer, and applying a voltage across the stack of quantum well layers to cause absorption of a portion of energy of the plasmonic current by the stack of quantum well layers. A metamaterial switching system includes a semiconductor substrate, a plurality of quantum well layers stacked on a top surface of the semiconductor substrate, and at least one metamaterial structure formed on a top surface of the stack of quantum well layers.

  9. 48 CFR 41.204 - GSA areawide contracts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false GSA areawide contracts. 41.204 Section 41.204 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL... entire geographical area covered by an areawide contract, although it may be available at...

  10. 41 CFR 101-30.705 - GSA assistance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true GSA assistance. 101-30.705 Section 101-30.705 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM...

  11. 41 CFR 101-30.705 - GSA assistance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false GSA assistance. 101-30.705 Section 101-30.705 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM...

  12. 41 CFR 101-30.705 - GSA assistance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 2 2011-07-01 2007-07-01 true GSA assistance. 101-30.705 Section 101-30.705 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM...

  13. 41 CFR 101-30.705 - GSA assistance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true GSA assistance. 101-30.705 Section 101-30.705 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM...

  14. 41 CFR 101-30.705 - GSA assistance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true GSA assistance. 101-30.705 Section 101-30.705 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 30-FEDERAL CATALOG SYSTEM...

  15. Potassium emission absorption system. Topical report 12

    SciTech Connect

    Bauman, L.E.

    1995-04-01

    The Potassium Emission Absorption System is one of the advanced optical diagnostics developed at Mississippi State University to provide support for the demonstration of prototype-scale coal-fired combustion magnetohydrodynamic (MHD) electrical power generation. Intended for application in the upstream of an MHD flow, the system directly measures gas temperature and neutral potassium atom number density through spectroscopic emission absorption techniques. From these measurements the electron density can be inferred from a statistical equilibrium calculation and the electron conductivity in the MHD channel found by use of an electron mobility model. The instrument has been utilized for field test measurements on MHD facilities for almost a decade and has been proven to provide useful measurements as designed for MHD nozzle, channel, and diffuser test sections. The theory of the measurements, a system description, its capabilities, and field test measurement results are reported here. During the development and application of the instrument several technical issues arose which when addressed advanced the state of the art in emission absorption measurement. Studies of these issues are also reported here and include: two-wavelength measurements for particle-laden flows, potassium D-line far wing absorption coefficient, bias in emission absorption measurements arising from dirty windows and misalignments, non-coincident multiwavelength emission absorption sampling errors, and lineshape fitting for boundary layer flow profile information. Although developed for NLHD application, the instrument could be applied to any high temperature flow with a resonance line in the 300 to 800 nm range, for instance other types of flames, rocket plumes or low temperature plasmas.

  16. Plug-Load Control and Behavioral Change Research in GSA Office Buildings

    SciTech Connect

    Metzger, I.; Cutler, D.; Sheppy, M.

    2012-10-01

    The U.S. General Services Administration (GSA) owns and leases over 354 million square feet (ft2) of space in over 9,600 buildings [1]. GSA is a leader among federal agencies in aggressively pursuing energy efficiency (EE) opportunities for its facilities and installing renewable energy (RE) systems to provide heating, cooling, and power to these facilities. According to several energy assessments of GSA's buildings conducted by the National Renewable Energy Laboratory (NREL), plug-loads account for approximately 21% of the total electricity consumed within a standard GSA Region 3 office building. This study aims to provide insight on how to effectively manage plug-load energy consumption and attain higher energy and cost savings for plug-loads. As GSA improves the efficiency of its building stock, plug-loads will become an even greater portion of its energy footprint.

  17. 41 CFR 101-1.4902 - GSA forms.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true GSA forms. 101-1.4902 Section 101-1.4902 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS GENERAL 1-INTRODUCTION 1.49-Illustrations of Forms §...

  18. 41 CFR 101-27.504 - Notice to GSA.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Notice to GSA. 101-27.504 Section 101-27.504 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 27-INVENTORY MANAGEMENT 27.5-Return of...

  19. Corrosion inhibitor for aqueous ammonia absorption system

    DOEpatents

    Phillips, B.A.; Whitlow, E.P.

    1998-09-22

    A method is described for inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425 F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25 C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425 F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer. 5 figs.

  20. Corrosion inhibitor for aqueous ammonia absorption system

    DOEpatents

    Phillips, Benjamin A.; Whitlow, Eugene P.

    1998-09-22

    A method of inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425.degree. F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25.degree. C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425.degree. F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer.

  1. Dilution cycle control for an absorption refrigeration system

    DOEpatents

    Reimann, Robert C.

    1984-01-01

    A dilution cycle control system for an absorption refrigeration system is disclosed. The control system includes a time delay relay for sensing shutdown of the absorption refrigeration system and for generating a control signal only after expiration of a preselected time period measured from the sensed shutdown of the absorption refrigeration system, during which the absorption refrigeration system is not restarted. A dilution cycle for the absorption refrigeration system is initiated in response to generation of a control signal by the time delay relay. This control system is particularly suitable for use with an absorption refrigeration system which is frequently cycled on and off since the time delay provided by the control system prevents needless dilution of the absorption refrigeration system when the system is turned off for only a short period of time and then is turned back on.

  2. 75 FR 28253 - Federal Management Regulation (FMR); Notice of GSA Bulletin FMR B-26

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-20

    ... to work with the Comptroller General and other executive agencies to develop accounting systems for... From the Federal Register Online via the Government Publishing Office GENERAL SERVICES... Governmentwide Policy, General Services Administration (GSA). ACTION: Notice of a bulletin. SUMMARY: This...

  3. Counterflow absorber for an absorption refrigeration system

    DOEpatents

    Reimann, Robert C.

    1984-01-01

    An air-cooled, vertical tube absorber for an absorption refrigeration system is disclosed. Strong absorbent solution is supplied to the top of the absorber and refrigerant vapor is supplied to the bottom of the absorber to create a direct counterflow of refrigerant vapor and absorbent solution in the absorber. The refrigeration system is designed so that the volume flow rate of refrigerant vapor in the tubes of the absorber is sufficient to create a substantially direct counterflow along the entire length of each tube in the absorber. This provides several advantages for the absorber such as higher efficiency and improved heat transfer characteristics, and allows improved purging of non-condensibles from the absorber.

  4. Spray generators for absorption refrigeration systems

    DOEpatents

    Sibley, Howard W.

    1979-06-19

    A spray generator for an absorption refrigeration system that includes a heat exchanger comprised of a multiplicity of variably spaced heat exchange tubes. The tubes are spaced close together near the top of the heat exchanger and spaced more widely apart near the bottom of the heat exchanger. Dilute absorbent solution is sprayed down through the heat exchanger. The close nesting of the tubes in the top portion of the heat exchanger retards liquid flow and aids heating of the solution. The wide spacing of the tubes in the lower section of the heat exchanger facilitate vapor flow out of the heat exchanger and eliminates liquid "blow-off". The top tubes are covered by a baffle to prevent the liquid solution from splashing out of the heat exchanger off of these top tubes.

  5. Heat exchanger bypass system for an absorption refrigeration system

    DOEpatents

    Reimann, Robert C.

    1984-01-01

    A heat exchanger bypass system for an absorption refrigeration system is disclosed. The bypass system operates to pass strong solution from the generator around the heat exchanger to the absorber of the absorption refrigeration system when strong solution builds up in the generator above a selected level indicative of solidification of strong solution in the heat exchanger or other such blockage. The bypass system includes a bypass line with a gooseneck located in the generator for controlling flow of strong solution into the bypass line and for preventing refrigerant vapor in the generator from entering the bypass line during normal operation of the refrigeration system. Also, the bypass line includes a trap section filled with liquid for providing a barrier to maintain the normal pressure difference between the generator and the absorber even when the gooseneck of the bypass line is exposed to refrigerant vapor in the generator. Strong solution, which may accumulate in the trap section of the bypass line, is diluted, to prevent solidification, by supplying weak solution to the trap section from a purge system for the absorption refrigeration system.

  6. Cloud Absorption Radiometer Autonomous Navigation System - CANS

    NASA Technical Reports Server (NTRS)

    Kahle, Duncan; Gatebe, Charles; McCune, Bill; Hellwig, Dustan

    2013-01-01

    CAR (cloud absorption radiometer) acquires spatial reference data from host aircraft navigation systems. This poses various problems during CAR data reduction, including navigation data format, accuracy of position data, accuracy of airframe inertial data, and navigation data rate. Incorporating its own navigation system, which included GPS (Global Positioning System), roll axis inertia and rates, and three axis acceleration, CANS expedites data reduction and increases the accuracy of the CAR end data product. CANS provides a self-contained navigation system for the CAR, using inertial reference and GPS positional information. The intent of the software application was to correct the sensor with respect to aircraft roll in real time based upon inputs from a precision navigation sensor. In addition, the navigation information (including GPS position), attitude data, and sensor position details are all streamed to a remote system for recording and later analysis. CANS comprises a commercially available inertial navigation system with integral GPS capability (Attitude Heading Reference System AHRS) integrated into the CAR support structure and data system. The unit is attached to the bottom of the tripod support structure. The related GPS antenna is located on the P-3 radome immediately above the CAR. The AHRS unit provides a RS-232 data stream containing global position and inertial attitude and velocity data to the CAR, which is recorded concurrently with the CAR data. This independence from aircraft navigation input provides for position and inertial state data that accounts for very small changes in aircraft attitude and position, sensed at the CAR location as opposed to aircraft state sensors typically installed close to the aircraft center of gravity. More accurate positional data enables quicker CAR data reduction with better resolution. The CANS software operates in two modes: initialization/calibration and operational. In the initialization/calibration mode

  7. Design for Manufacturing for Energy Absorption Systems

    SciTech Connect

    Del Prete, A.; Primo, T.; Papadia, G.; Manisi, B.

    2011-05-04

    In the typical scenario of a helicopter crash, impact with the ground is preceded by a substantially vertical drop, with the result that a seated occupant of a helicopter experiences high spinal loads and pelvic deceleration during such crash due to the sudden arresting of vertical downward motion. It has long been recognized that spinal injuries to occupants of helicopters in such crash scenario can be minimized by seat arrangements which limit the deceleration to which the seated occupant is subjected, relative to the helicopter, to a predetermined maximum, by allowing downward movement of the seated occupant relative to the helicopter, at the time of impact with the ground, under a restraining force which, over a limited range of such movement, is limited to a predetermined maximum. In practice, significant benefits, in the way of reduced injuries and reduced seriousness of injuries, can be afforded in this way in such crash situations even where the extent of such controlled vertical movement permitted by the crashworthy seat arrangement is quite limited. Important increase of accident safety is reached with the installation of crashworthy shock absorbers on the main landing gear, but this solution is mostly feasible on military helicopters with long fixed landing gear. Seats can then give high contribution to survivability. Commonly, an energy absorber is a constant load device, if one excludes an initial elastic part of the load-stroke curve. On helicopter seats, this behavior is obtained by plastic deformation of a metal component or scraping of material. In the present work the authors have studied three absorption systems, which differ in relation to their shape, their working conditions and their constructive materials. All the combinations have been analyzed for applications in VIP helicopter seats.

  8. Nanofibrous membrane-based absorption refrigeration system

    SciTech Connect

    Isfahani, RN; Sampath, K; Moghaddam, S

    2013-12-01

    This paper presents a study on the efficacy of highly porous nanofibrous membranes for application in membrane-based absorbers and desorbers. Permeability studies showed that membranes with a pore size greater than about one micron have a sufficient permeability for application in the absorber heat exchanger. Membranes with smaller pores were found to be adequate for the desorber heat exchanger. The membranes were implemented in experimental membrane-based absorber and desorber modules and successfully tested. Parametric studies were conducted on both absorber and desorber processes. Studies on the absorption process were focused on the effects of water vapor pressure, cooling water temperature, and the solution velocity on the absorption rate. Desorption studies were conducted on the effects of wall temperature, vapor and solution pressures, and the solution velocity on the desorption rate. Significantly higher absorption and desorption rates than in the falling film absorbers and desorbers were achieved. Published by Elsevier Ltd.

  9. 41 CFR 105-56.016 - GSA participation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....S.C. 5514(a)(1), GSA must participate at least annually in centralized salary offset computer... delinquent for more than 180 days for purposes of administrative offset, as required under 31 U.S.C. 3716(c... within ten years after GSA's right of action accrues; (3) GSA has complied with the provisions of 31...

  10. Dust in MG II Absorption Systems

    NASA Astrophysics Data System (ADS)

    Malhotra, S.

    The dust absorption feature at 2175 AA is detected in a composite spectrum of Mg II absorbers. The composite absorber spectrum is obtained by taking the geometric mean of 92 quasar spectra after aligning them in the rest-frame of 96 absorbers. By aligning the spectra according to absorber redshifts we reinforce the spectral features of the absorbers, and smooth over possible bumps and wiggles in the emission spectra. The width of the observed absorption feature is 200-300 AA (FWHM), or 0.4-0.6 microns^{-1} and the central wavelength is 2240 AA. The Galactic dust feature has a central wavelength of 2176 AA and FWHM = 0.8-1.25 microns^{-1}. Simulations show that this discrepancy between the properties of the 2175 AA feature in Mg II absorbers and Galactic ISM can be mostly explained by the different methods used to measure them (cf. Malhotra 1997).

  11. 25. View down launch tube, showing shock absorption system. Lyon ...

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

    25. View down launch tube, showing shock absorption system. Lyon - Whiteman Air Force Base, Minuteman Missile Launch Facility Trainer T-12, Northeast of Oscar-01 Missile Alert Facility, Knob Noster, Johnson County, MO

  12. Electromagnetically induced absorption in a three-resonator metasurface system

    PubMed Central

    Zhang, Xueqian; Xu, Ningning; Qu, Kenan; Tian, Zhen; Singh, Ranjan; Han, Jiaguang; Agarwal, Girish S.; Zhang, Weili

    2015-01-01

    Mimicking the quantum phenomena in metamaterials through coupled classical resonators has attracted enormous interest. Metamaterial analogs of electromagnetically induced transparency (EIT) enable promising applications in telecommunications, light storage, slow light and sensing. Although the EIT effect has been studied extensively in coupled metamaterial systems, excitation of electromagnetically induced absorption (EIA) through near-field coupling in these systems has only been sparsely explored. Here we present the observation of the EIA analog due to constructive interference in a vertically coupled three-resonator metamaterial system that consists of two bright and one dark resonator. The absorption resonance is one of the collective modes of the tripartite unit cell. Theoretical analysis shows that the absorption arises from a magnetic resonance induced by the near-field coupling of the three resonators within the unit cell. A classical analog of EIA opens up opportunities for designing novel photonic devices for narrow-band filtering, absorptive switching, optical modulation, and absorber applications. PMID:26023061

  13. Christiansen effect in disperse systems with resonant absorption

    SciTech Connect

    Zimnyakov, D A; Isaeva, Elmira A; Isaeva, A A

    2012-01-31

    We discuss the results of experimental studies of competition of absorption and scattering of laser radiation propagating in dispersive media with resonant absorption. As media under study, use is made of a suspension of polystyrene particles in solutions of rhodamine 6G in ethylene glycol probed by laser light with a wavelength of 532 nm. It is found that an increase in the dye concentration leads to an increase in optical transmittance of suspensions and an increase in speckle modulation of the forward-scattered radiation. We interpret these features as a manifestation of Christiansen effect in disperse systems with resonance absorption.

  14. 48 CFR 515.209-70 - Examination of records by GSA clause.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Examination of records by GSA clause. 515.209-70 Section 515.209-70 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Solicitation and Receipt...

  15. 41 CFR 101-26.4902-1781 - GSA Form 1781, Motor Vehicle Requisition-Delivery Order.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true GSA Form 1781, Motor Vehicle Requisition-Delivery Order. 101-26.4902-1781 Section 101-26.4902-1781 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT...

  16. 41 CFR 101-26.4902-1781 - GSA Form 1781, Motor Vehicle Requisition-Delivery Order.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true GSA Form 1781, Motor Vehicle Requisition-Delivery Order. 101-26.4902-1781 Section 101-26.4902-1781 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT...

  17. 41 CFR 101-26.4902-1781 - GSA Form 1781, Motor Vehicle Requisition-Delivery Order.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false GSA Form 1781, Motor Vehicle Requisition-Delivery Order. 101-26.4902-1781 Section 101-26.4902-1781 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT...

  18. 41 CFR 101-26.4902-1398 - GSA Form 1398: Motor vehicle purchase and inspection label.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false GSA Form 1398: Motor vehicle purchase and inspection label. 101-26.4902-1398 Section 101-26.4902-1398 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT...

  19. 41 CFR 101-26.4902-1398 - GSA Form 1398: Motor vehicle purchase and inspection label.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 2 2011-07-01 2007-07-01 true GSA Form 1398: Motor vehicle purchase and inspection label. 101-26.4902-1398 Section 101-26.4902-1398 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT...

  20. 41 CFR 101-26.4902-1398 - GSA Form 1398: Motor vehicle purchase and inspection label.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true GSA Form 1398: Motor vehicle purchase and inspection label. 101-26.4902-1398 Section 101-26.4902-1398 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT...

  1. 41 CFR 101-26.4902-1781 - GSA Form 1781, Motor Vehicle Requisition-Delivery Order.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 2 2011-07-01 2007-07-01 true GSA Form 1781, Motor Vehicle Requisition-Delivery Order. 101-26.4902-1781 Section 101-26.4902-1781 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT...

  2. 41 CFR 101-26.4902-1398 - GSA Form 1398: Motor vehicle purchase and inspection label.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true GSA Form 1398: Motor vehicle purchase and inspection label. 101-26.4902-1398 Section 101-26.4902-1398 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT...

  3. 41 CFR 105-62.103 - Access to GSA-originated materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... of General Services in 41 CFR part 105-61. (e) Access by the General Accounting Office and... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Access to GSA-originated... Management Regulations System (Continued) GENERAL SERVICES ADMINISTRATION Regional Offices-General...

  4. 41 CFR 105-62.103 - Access to GSA-originated materials.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... of General Services in 41 CFR part 105-61. (e) Access by the General Accounting Office and... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Access to GSA-originated... Management Regulations System (Continued) GENERAL SERVICES ADMINISTRATION Regional Offices-General...

  5. 41 CFR 105-62.103 - Access to GSA-originated materials.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... of General Services in 41 CFR part 105-61. (e) Access by the General Accounting Office and... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Access to GSA-originated... Management Regulations System (Continued) GENERAL SERVICES ADMINISTRATION Regional Offices-General...

  6. 41 CFR 105-60.305-3 - GSA records available without charge.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false GSA records available without charge. 105-60.305-3 Section 105-60.305-3 Public Contracts and Property Management Federal Property Management Regulations System (Continued) GENERAL SERVICES ADMINISTRATION Regional...

  7. 48 CFR 552.219-75 - GSA Mentor-Protégé Program.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false GSA Mentor-ProtégÃ... Mentor-ProtéGé Program (SEP 2009) (a) Prime contractors, including small businesses, are encouraged to.... (b) The Program consists of: (1) Mentor firms are large prime contractors with at least one...

  8. Middle infrared optoelectronic absorption systems for monitoring physiological glucose solutions

    NASA Astrophysics Data System (ADS)

    Martin, W. Blake

    Tight monitoring of the glucose levels for diabetic individuals is essential to control long-term complications. A definitive diabetes management system has yet to be developed for the diabetic. This research investigates the application of middle infrared absorption frequencies for monitoring glucose levels in biological solutions. Three frequencies were identified using a Fourier transform infrared spectrometer and correlated to changes in glucose concentrations. The 1035 +/- 1 cm-1 frequency was determined to be the best representative frequency. Other biological molecules contributed no significant interference to monitoring glucose absorption. A second frequency at 1193 cm-1 was suggested as a representative background absorption frequency, which could be used for more accurate glucose absorption values. Next, a quantum cascade laser optoelectronic absorption system was designed and developed to monitor glucose. After careful alignment and design, the system was used to monitor physiological glucose concentrations. Correlation at 1036 cm-1 with glucose changes was comparable to the previous results. The use of the background absorption frequency was verified. This frequency essentially acts as a calibrating frequency to adjust in real-time to any changes in the background absorption that may alter the accuracy of the predicted glucose value. An evanescent wave cavity ring-down spectroscopy technique was explored to monitor molecules in a biological solution. Visible light at 425 nm was used to monitor hemoglobin in control urine samples. An adsorption isotherm for hemoglobin was detectable to limit of 5.8 nM. Evanescent wave cavity ring-down spectroscopy would be useful for a glucose solution. Given an equivalent system designed for the middle infrared, the molar extinction coefficient of glucose allows for a detectable limit of 45 mg/dl for a free-floating glucose solution, which is below normal physiological concentrations. The future use of a hydrophobic

  9. Theoretical Study of New Combined Absorption-Ejector Refrigeration System

    NASA Astrophysics Data System (ADS)

    Abed, A. M.; Sopian, K.; Alghoul, M. A.; Al-Shamani, A. N.; Ruslan, M. H.; Mat, S.

    2015-09-01

    An improved system of the new combined single stage absorption cycle operated with NH3/H2O as working fluid was performed. In order to enhance performance the cycle a new configuration of absorption system was utilized. The performances of two configurations of the combined absorption cycle were compared; a) with common solution heat exchanger and b) divided the streamline of solution heat exchanger to recover the internal heat. Based on the analysis, it has been shown that the second configuration a significant reduction of the required generator and absorber loads by about 20% and 17% respectively, with increased coefficient of performance (COP) about 12% compared to the first configuration. This improvement in the overall COP is found due to improve energy utilization efficiency significantly.

  10. Waste heat driven absorption refrigeration process and system

    DOEpatents

    Wilkinson, William H.

    1982-01-01

    Absorption cycle refrigeration processes and systems are provided which are driven by the sensible waste heat available from industrial processes and other sources. Systems are disclosed which provide a chilled water output which can be used for comfort conditioning or the like which utilize heat from sensible waste heat sources at temperatures of less than 170.degree. F. Countercurrent flow equipment is also provided to increase the efficiency of the systems and increase the utilization of available heat.

  11. 41 CFR 105-56.026 - GSA participation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Offset (CSO) Procedures-GSA as Paying Agency § 105-56.026 GSA participation. (a) As required under 5 U.S... computer matching. To meet this requirement, creditor agencies will notify FMS of all past-due, legally... 31 U.S.C. 3716(c)(6). Additionally, creditor agencies may notify FMS of past-due, legally...

  12. 41 CFR 101-25.203 - Centralized purchases by GSA.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Centralized purchases by...-Interagency Purchase Assignments § 101-25.203 Centralized purchases by GSA. GSA will exclusively, or with specified limited exceptions, make purchases and contracts on a continuing basis for articles and...

  13. 32 CFR 644.344 - Coordination with GSA.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Coordination with GSA. 644.344 Section 644.344 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearances-Army Military Real Property § 644.344 Coordination with GSA. At...

  14. 78 FR 79460 - Notification of GSA Strategic Plan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-30

    ... ADMINISTRATION Notification of GSA Strategic Plan AGENCY: Office of the Chief Financial Officer, U.S. General... announcing the availability of the Draft FY 2014-2018 GSA Strategic Plan for public review and comment, as... Act of 2010. The agency anticipates the final Strategic Plan will be submitted to Congress with...

  15. 41 CFR 101-27.209-1 - GSA stock items.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true GSA stock items. 101-27.209-1 Section 101-27.209-1 Public Contracts and Property Management Federal Property Management...-Management of Shelf-Life Materials § 101-27.209-1 GSA stock items. Shelf-life items that meet the...

  16. 41 CFR 101-25.203 - Centralized purchases by GSA.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 2 2011-07-01 2007-07-01 true Centralized purchases by...-Interagency Purchase Assignments § 101-25.203 Centralized purchases by GSA. GSA will exclusively, or with specified limited exceptions, make purchases and contracts on a continuing basis for articles and...

  17. 32 CFR 644.344 - Coordination with GSA.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Coordination with GSA. 644.344 Section 644.344 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearances-Army Military Real Property § 644.344 Coordination with GSA. At...

  18. The distribution of absorptive power dissipation in irradiated nanoparticulate system

    NASA Astrophysics Data System (ADS)

    Li, Jiayu; Yang, Jian; Gu, Xiaobing

    2016-10-01

    The knowledge of local radiant absorption is important to the nanostructure optimization, it is beneficial to the applications in energy harvesting, optical heating, photocatalysis, etc. In this paper, FDTD model is constructed for the distribution of absorptive power dissipation in irradiated nanoparticulate system. The theoretical model extended from Mie theory is used to examine the FDTD model, the parameters and conditions set for FDTD simulation are confirmed based on the comparison. Then, the influence of Ag nanoparticle on the absorptive properties of nearby TiO2 nanoparticle is investigated by FDTD simulation at the wavelength of 0.25 μm. It is indicated that suitable distance between TiO2 and Ag particles is beneficial to the spectral radiant absorption of TiO2 particle. Considering the agglomeration of nanoparticles and the oxidation at the TiO2-Ag interface, the Ag core coated with Al2O3 shell is suggested, and the simulated results indicated that the shell thickness and the Ag core size need to be optimized for enhancing the radiant absorption of TiO2 particle.

  19. Backscatter absorption gas imaging systems and light sources therefore

    DOEpatents

    Kulp, Thomas Jan; Kliner, Dahv A. V.; Sommers, Ricky; Goers, Uta-Barbara; Armstrong, Karla M.

    2006-12-19

    The location of gases that are not visible to the unaided human eye can be determined using tuned light sources that spectroscopically probe the gases and cameras that can provide images corresponding to the absorption of the gases. The present invention is a light source for a backscatter absorption gas imaging (BAGI) system, and a light source incorporating the light source, that can be used to remotely detect and produce images of "invisible" gases. The inventive light source has a light producing element, an optical amplifier, and an optical parametric oscillator to generate wavelength tunable light in the IR. By using a multi-mode light source and an amplifier that operates using 915 nm pump sources, the power consumption of the light source is reduced to a level that can be operated by batteries for long periods of time. In addition, the light source is tunable over the absorption bands of many hydrocarbons, making it useful for detecting hazardous gases.

  20. Transient absorption measurement system using pulsed energetic ion

    NASA Astrophysics Data System (ADS)

    Taguchi, Mitsumasa; Baldacchino, Gérard; Kurashima, Satoshi; Kimura, Atsushi; Sugo, Yumi; Katsumura, Yosuke; Hirota, Koichi

    2009-12-01

    This article reports a highly sensitive transient absorbance measurement system using pulsed energetic ions. The ions were pulsed by a beam chopper, which was synchronized with the cyclotron, and accelerated to the desired energy around 18 MeV/u. H, He, C and Ne ions can be used for the transient absorption measurement. The optical system can measure an absorbance smaller than 1.0×10 -4 in the wavelength range of 400-740 nm.

  1. Differential absorption lidar system for routine monitoring of tropospheric ozone.

    PubMed

    Sunesson, J A; Apituley, A; Swart, D P

    1994-10-20

    A differential absorption lidar system for routine profiling of tropospheric ozone for daytime and nighttime operation is described. The system uses stimulated Raman scattering in hydrogen and deuterium of 266-nm radiation from a quadrupled Nd:YAG laser. Ozone profiles from altitudes of 600 m to approximately 5 km have been obtained with analog detection. Implementing corrections for differential Rayleigh scattering, differential absorption from oxygen, sulphur dioxide, and nitrogen dioxide, and differential aerosol extinction and backscatter can reduce the total system inaccuracy to 5-15% for a clear day and 20-30% for a hazy day, except at the top of the mixed layer. Photon counting must be installed to increase the measurement range from 5 to 15 km. An example of an application of routine measurements of tropospheric ozone profiles is given.

  2. NASA three-laser airborne differential absorption lidar system electronics

    NASA Technical Reports Server (NTRS)

    Allen, R. J.; Copeland, G. D.

    1984-01-01

    The system control and signal conditioning electronics of the NASA three laser airborne differential absorption lidar (DIAL) system are described. The multipurpose DIAL system was developed for the remote measurement of gas and aerosol profiles in the troposphere and lower stratosphere. A brief description and photographs of the majority of electronics units developed under this contract are presented. The precision control system; which includes a master control unit, three combined NASA laser control interface/quantel control units, and three noise pulse discriminator/pockels cell pulser units; is described in detail. The need and design considerations for precision timing and control are discussed. Calibration procedures are included.

  3. Stabilized master laser system for differential absorption lidar.

    PubMed

    Dinovitser, Alex; Hamilton, Murray W; Vincent, Robert A

    2010-06-10

    Wavelength accuracy and stability are key requirements for differential absorption lidar (DIAL). We present a control and timing design for the dual-stabilized cw master lasers in a pulsed master-oscillator power-amplifier configuration, which forms a robust low-cost water-vapor DIAL transmitter system. This design operates at 823 nm for water-vapor spectroscopy using Fabry-Perot-type laser diodes. However, the techniques described could be applied to other laser technologies at other wavelengths. The system can be extended with additional off-line or side-line wavelengths. The on-line master laser is locked to the center of a water absorption line, while the beat frequency between the on-line and the off-line is locked to 16 GHz using only a bandpass microwave filter and low-frequency electronics. Optical frequency stabilities of the order of 1 MHz are achieved.

  4. High Performance Drying System Using Absorption Temperature Amplifier

    NASA Astrophysics Data System (ADS)

    Nomura, Tomohiro; Nishimura, Nobuya; Yabushita, Akihiro; Kashiwagi, Takao

    It is highly essential to create a high performance drying technology from the viewpoint of energy conservation. Recently the drying process using superheated steam has received a great attention for improving the energy efficiency of the conventional air drying processes. Many other advantages of this superheated steam drying include its inert atmosphere, enhanced drying rate, improved product quality and easier control. This study presents a new concept of superheated steam drying in which the absorption temperature amplifier is effectively applied in order to recover the waste heat with high efficiency. A feature of this new drying system is that, owing to a closed circuit dryer, the consumption of heating energy decreases by approximately 50% of the conventional noncirculated one, and the superheated steam conventionally discharged so as to maintain the pressure of the dryer at an atmospheric one can be reused as heating energy for the generator of the absorption temperature amplifier. In the 1st report, thermal performances of this proposed system have been analyzed by a computer simulation developed for the solar-assisted absorption heat transformer model at the steady-state operating condition. It may be fair to conclude that this drying system satisfies the desired operating conditions, although it involves some problems to be solved further in detail in future.

  5. Triple loop heat exchanger for an absorption refrigeration system

    DOEpatents

    Reimann, Robert C.

    1984-01-01

    A triple loop heat exchanger for an absorption refrigeration system is disclosed. The triple loop heat exchanger comprises portions of a strong solution line for conducting relatively hot, strong solution from a generator to a solution heat exchanger of the absorption refrigeration system, conduit means for conducting relatively cool, weak solution from the solution heat exchanger to the generator, and a bypass system for conducting strong solution from the generator around the strong solution line and around the solution heat exchanger to an absorber of the refrigeration system when strong solution builds up in the generator to an undesirable level. The strong solution line and the conduit means are in heat exchange relationship with each other in the triple loop heat exchanger so that, during normal operation of the refrigeration system, heat is exchanged between the relatively hot, strong solution flowing through the strong solution line and the relatively cool, weak solution flowing through the conduit means. Also, the strong solution line and the bypass system are in heat exchange relationship in the triple loop heat exchanger so that if the normal flow path of relatively hot, strong solution flowing from the generator to an absorber is blocked, then this relatively, hot strong solution which will then be flowing through the bypass system in the triple loop heat exchanger, is brought into heat exchange relationship with any strong solution which may have solidified in the strong solution line in the triple loop heat exchanger to thereby aid in desolidifying any such solidified strong solution.

  6. Absorption and adsorption chillers applied to air conditioning systems

    NASA Astrophysics Data System (ADS)

    Kuczyńska, Agnieszka; Szaflik, Władysław

    2010-07-01

    This work presents an application possibility of sorption refrigerators driven by low temperature fluid for air conditioning of buildings. Thermodynamic models were formulated and absorption LiBr-water chiller with 10 kW cooling power as well as adsorption chiller with silica gel bed were investigated. Both of them are using water for desorption process with temperature Tdes = 80 °C. Coefficient of performance (COP) for both cooling cycles was analyzed in the same conditions of the driving heat source, cooling water Tc = 25 °C and temperature in evaporator Tevap = 5 °C. In this study, the computer software EES was used to investigate the performance of absorption heat pump system and its behaviour in configuration with geothermal heat source.

  7. High Performance Drying System Using Absorption Temperature Amplifier

    NASA Astrophysics Data System (ADS)

    Nishimura, Nobuya; Nomura, Tomohiro; Yabushita, Akihiro; Kashiwagi, Takao

    A computer simulation has been developed on transient drying process in order to predict the dynamic thermal performance of a new superheated steam drying system using an absorption type temperature amplifier as a steam superheater. A feature of this drying system is that one can reuse the exhausted superheated stream conventionally discharged from the dryer as a driving heat source for the generator in this heat pump. But in the transient drying process, the evaporation of moisture sharply decreases. Accordingly, it is hardly expected to reuse an exhausted superheated steam as heating source for the generator. 80 the effects of this exhausted superheated steam and of changes in hot water and the cooling water temperatures were mainly investigated checking whether this drying system can be driven directly by the low level energy of sun or waste heat. Furthermore, the system performances of this drying system were evaluated on a qualitative-basis by using the exergy efficiency. The results show that, under the transient drying conditions, the temperature boost of superheated steam is possible at a high temperature and thus the absorption type temperature amplifier can be an effective steam superheater system.

  8. System Analysis on Absorption Chiller Utilizing Intermediate Wasted Heat

    NASA Astrophysics Data System (ADS)

    Yamada, Miki; Suzuki, Hiroshi; Usui, Hiromoto

    A system analysis has been performed for the multi-effect absorption chiller (MEAC) applied as a bottoming system of 30kW class hybrid system including micro gas turbine (MGT) and solid oxide fuel cell (SOFC) hybrid system. In this paper, an intermediate wasted heat utilization (IWHU) system is suggested for lifting up the energy efficiency of the whole system and coefficient of performance (COP) of MEAC. From the results, the suggested IWHU system was found to show the very high energy efficiency compared with a terminal wasted heat utilization (TWHU) system that uses only the heat exhausted from the terminal of MGT/SOFC system. When TWHU system is applied for MEAC, the utilized heat from the MGT/SOFC system is found to remain low because the temperature difference between the high temperature generator and the wasted heat becomes small. Then, the energy efficiency does not become high in spite of high COP of MEAC. On the other hand, the IWHU system could increase the utilized heat for MEAC as performs effectively. The exergy efficiency of IWHU system is also revealed to be higher than that of a direct gas burning system of MEAC, because the wasted heat is effectively utilized in the IWHU system.

  9. Laser absorption spectroscopy system for vaporization process characterization and control

    NASA Astrophysics Data System (ADS)

    Galkowski, Joseph J.; Hagans, Karla G.

    1994-03-01

    In support of the Lawrence Livermore National Laboratory's (LLNL's) Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) Program, a laser atomic absorption spectroscopy (LAS) system has been developed. This multilaser system is capable of simultaneously measuring the line densities of 238U ground and metastable states, 235U ground and metastable states, iron, and ions at up to nine locations within the separator vessel. Supporting enrichment experiments that last over one hundred hours, this laser spectroscopy system is employed to diagnose and optimize separator system performance, control the electron beam vaporizer and metal feed systems, and provide physics data for the validation of computer models. As a tool for spectroscopic research, vapor plume characterization, vapor deposition monitoring, and vaporizer development, LLNL's LAS laboratory with its six argon-ion-pumped ring dye lasers and recently added Ti:Sapphire and external-cavity diode- lasers has capabilities far beyond the requirements of its primary mission.

  10. GSA committees: Progress through service the Annual Program Committee

    USGS Publications Warehouse

    Costa, J.E.

    2007-01-01

    The GSA's Annual Program Committee (APC) is directly responsible for the GSA's meeting and other responsibilities especially before the main event. It decides on the locations, the number and content of the technical sessions, annual membership surveys, hospitality for the guests, field trips and more. In addition, it pays significant attention to creative thinking about geoscience discoveries and directions as well as identify new and emerging areas of earth science. APC is also looking for new ideas, approaches and directions.

  11. 48 CFR 552.212-71 - Contract Terms and Conditions Applicable to GSA Acquisition of Commercial Items.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Contract Terms and Conditions Applicable to GSA Acquisition of Commercial Items. 552.212-71 Section 552.212-71 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and...

  12. 48 CFR 52.211-1 - Availability of Specifications Listed in the GSA Index of Federal Specifications, Standards and...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Availability of Specifications Listed in the GSA Index of Federal Specifications, Standards and Commercial Item Descriptions, FPMR Part 101-29. 52.211-1 Section 52.211-1 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND...

  13. 48 CFR 52.211-1 - Availability of Specifications Listed in the GSA Index of Federal Specifications, Standards and...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Availability of Specifications Listed in the GSA Index of Federal Specifications, Standards and Commercial Item Descriptions, FPMR Part 101-29. 52.211-1 Section 52.211-1 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND...

  14. 48 CFR 52.211-3 - Availability of Specifications Not Listed in the GSA Index of Federal Specifications, Standards...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Availability of Specifications Not Listed in the GSA Index of Federal Specifications, Standards and Commercial Item Descriptions. 52.211-3 Section 52.211-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND FORMS...

  15. 48 CFR 52.211-4 - Availability for Examination of Specifications Not Listed in the GSA Index of Federal...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Availability for Examination of Specifications Not Listed in the GSA Index of Federal Specifications, Standards and Commercial Item Descriptions. 52.211-4 Section 52.211-4 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND...

  16. 48 CFR 52.211-3 - Availability of Specifications Not Listed in the GSA Index of Federal Specifications, Standards...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Availability of Specifications Not Listed in the GSA Index of Federal Specifications, Standards and Commercial Item Descriptions. 52.211-3 Section 52.211-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND FORMS...

  17. 48 CFR 52.211-4 - Availability for Examination of Specifications Not Listed in the GSA Index of Federal...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Availability for Examination of Specifications Not Listed in the GSA Index of Federal Specifications, Standards and Commercial Item Descriptions. 52.211-4 Section 52.211-4 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND...

  18. 48 CFR 52.211-4 - Availability for Examination of Specifications Not Listed in the GSA Index of Federal...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Availability for Examination of Specifications Not Listed in the GSA Index of Federal Specifications, Standards and Commercial Item Descriptions. 52.211-4 Section 52.211-4 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND...

  19. 48 CFR 52.211-3 - Availability of Specifications Not Listed in the GSA Index of Federal Specifications, Standards...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Availability of Specifications Not Listed in the GSA Index of Federal Specifications, Standards and Commercial Item Descriptions. 52.211-3 Section 52.211-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND FORMS...

  20. 48 CFR 52.211-1 - Availability of Specifications Listed in the GSA Index of Federal Specifications, Standards and...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Availability of Specifications Listed in the GSA Index of Federal Specifications, Standards and Commercial Item Descriptions, FPMR Part 101-29. 52.211-1 Section 52.211-1 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND...

  1. Tunable Optomechanically Induced Absorption in a Hybrid Optomechanical System

    NASA Astrophysics Data System (ADS)

    Wang, Qiong; Zhao, Yun-Hui; He, Zhi; Yao, Chun-Mei

    2016-03-01

    We study the tunable optomechanically induced absorption (OMIA) with the quantized field in the system, which consists of a driven cavity and a mechanical resonator with a super-conducting charge qubit via Jaynes-Cummings interaction. Such a OMIA can be achieved by controlling the strength of the Jaynes-Cummings interaction. Moreover, our work shows this OMIA for the quantized fields can be robust against cavity decay in somehow. With the combination of optomechanically induced transparency (OMIT), our proposal may have paved a new avenue towards quantum photon router.

  2. Pulsed laser linescanner for a backscatter absorption gas imaging system

    DOEpatents

    Kulp, Thomas J.; Reichardt, Thomas A.; Schmitt, Randal L.; Bambha, Ray P.

    2004-02-10

    An active (laser-illuminated) imaging system is described that is suitable for use in backscatter absorption gas imaging (BAGI). A BAGI imager operates by imaging a scene as it is illuminated with radiation that is absorbed by the gas to be detected. Gases become "visible" in the image when they attenuate the illumination creating a shadow in the image. This disclosure describes a BAGI imager that operates in a linescanned manner using a high repetition rate pulsed laser as its illumination source. The format of this system allows differential imaging, in which the scene is illuminated with light at least 2 wavelengths--one or more absorbed by the gas and one or more not absorbed. The system is designed to accomplish imaging in a manner that is insensitive to motion of the camera, so that it can be held in the hand of an operator or operated from a moving vehicle.

  3. Clean Coal Technology III (CCT III): 10 MW demonstration of gas suspension absorption. Technical progress report, fourth quarter, FY 1991 (10/01/91--12/31/91)

    SciTech Connect

    1995-05-01

    In response to the third Clean Coal Technology Program solicitation, AirPol Inc. submitted a proposal for the design, installation and testing of the Gas Suspension Absorption (GSA) system at Tennessee Valley Authority`s (TVA) Shawnee Test Facility (STF). This low-cost retrofit project will demonstrate the GSA system which is expected to remove more than 90% of the SO{sub 2} from coal-fired flue gas, while achieving a high utilization of reagent lime. The host site facility will be the STF located at the Shawnee Fossil Plant in West Paducah, Kentucky. Over the past 15 years, the STF has served as a testground for flue gas desulfurization (FGD) systems. At the present time a semi-dry process employing 10 MW capacity spray dryer is being tested at the facility. Upon completion of the current spray dryer test, the GSA system will be tested for a period of eleven months. The GSA system brings coal combustion gases into contact with a suspended mixture of solids, including sulfur-absorbing lime. After the lime absorbs the sulfur pollutants, the solids are separated from the gases in a cyclone device and recirculated back into the system where they capture additional sulfur pollutant. The cleaned flue gases are sent through a dust collector before being released into the atmosphere. The key to the system`s superior economic performance with high sulfur coals is the recirculation of solids. Typically, a solid particle will pass through the system about one hundred times before leaving the system. Another advantage of the GSA system is that a single spray nozzle is used to inject fresh lime slurry.

  4. INTERSTELLAR SILICATE DUST IN FIVE QUASAR ABSORPTION SYSTEMS

    SciTech Connect

    Kulkarni, Varsha P.; Torres-Garcia, Legna M.; Som, Debopam; York, Donald G.; Welty, Daniel E.; Vladilo, Giovanni

    2011-01-01

    We report on a study of interstellar silicate dust in five quasar absorption systems at 0.44 < z{sub abs} < 1.31 toward quasars Q0235+164, 3C196, Q0852+3435, Q0937+5628, and Q1203+0634, using data from the Infrared Spectrograph on board the Spitzer Space Telescope. In the absorbers toward Q0235+164, 3C196, Q0852+3435, and Q0937+5628, the 9.7 {mu}m silicate feature is detected in absorption at {approx}5{sigma}-10{sigma} significance, with rest-frame equivalent widths of {approx}0.2-0.5 {mu}m. For Q1203+0634, the noisy data allow us to make only a 3.6{sigma} detection of absorption at 10 {mu}m. Fits to the redshifted 9.7 {mu}m features with four possible template profiles indicate that the laboratory amorphous olivine profile generally provides the best fit, with inferred peak optical depths of {tau}{sub 9.7} {approx} 0.08-0.18. For three of the quasars with optical spectra available from the Sloan Digital Sky Survey, the Large Magellanic Cloud supershell extinction curve provides the best formal fits, with E(B - V) of 0.34-0.54 mag. A 2175 A extinction bump at the absorber redshift (known to exist in Q0235+164) appears to be present at >2.8{sigma} level in Q0852+3435, >2.5{sigma} level in Q1203+0634, and marginally at nearly 2{sigma} level in Q0937+5628. We briefly explore possible correlations between {tau}{sub 9.7} and the color excess, the strength of the 2175 A bump, and the metallicity (which appears to be relatively high for these absorbers, in the range of {approx}>0.1 solar to supersolar). While our measurements are consistent with a linear relation between {tau}{sub 9.7} and E(B - V), the {tau}{sub 9.7}/E(B - V) ratios for these quasar absorbers appear to be higher than those for diffuse interstellar clouds in the Milky Way, closer to values observed for the Galactic center. Some of these quasar sightlines may trace regions in the bulges of the galaxies responsible for the absorption systems.

  5. Evaluation of absorption cycle for space station environmental control system application

    NASA Technical Reports Server (NTRS)

    Sims, W. H.; Oneill, M. J.; Reid, H. C.; Bisenius, P. M.

    1972-01-01

    The study to evaluate an absorption cycle refrigeration system to provide environmental control for the space stations is reported. A zero-gravity liquid/vapor separator was designed and tested. The results were used to design a light-weight, efficient generator for the absorption refrigeration system. It is concluded that absorption cycle refrigeration is feasible for providing space station environmental control.

  6. 41 CFR 102-118.25 - Does GSA still require my agency to submit its overall transportation policies for approval?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION TRANSPORTATION 118-TRANSPORTATION PAYMENT AND AUDIT General Introduction... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Does GSA still...

  7. 41 CFR 102-118.615 - Will GSA notify a TSP if they internally offset a payment?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Will GSA notify a TSP if they internally offset a payment? 102-118.615 Section 102-118.615 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION TRANSPORTATION 118-TRANSPORTATION PAYMENT AND...

  8. 41 CFR 102-36.55 - What is GSA's role in the disposition of excess personal property?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What is GSA's role in the disposition of excess personal property? 102-36.55 Section 102-36.55 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION...

  9. 41 CFR 102-192.90 - What must we include in our annual mail management report to GSA?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... service provider to ship parts and supplies from a materiel distribution center (see the definition of... publication called “Marketips,” which provides information about supplies and services available through GSA... Systems Manager, Executive Mail Center Manager, Mailpiece Quality Control Specialist, Certified...

  10. 41 CFR 102-118.530 - Will GSA instruct my agency's disbursing offices to offset unpaid TSP billings?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION TRANSPORTATION 118-TRANSPORTATION PAYMENT AND AUDIT Claims and Appeal Procedures... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Will GSA instruct...

  11. 41 CFR 102-118.510 - Can my agency revise or alter a GSA Form 7931, Certificate of Settlement?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Can my agency revise or... Information for All Claims § 102-118.510 Can my agency revise or alter a GSA Form 7931, Certificate...

  12. 41 CFR 105-64.111 - What is GSA's policy on directives that may conflict with this part?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What is GSA's policy on directives that may conflict with this part? 105-64.111 Section 105-64.111 Public Contracts and Property Management Federal Property Management Regulations System (Continued) GENERAL SERVICES...

  13. Simulation of Absorption Systems in Flexible and Modular Form

    1994-09-23

    The computer code has been developed for simulation of absorption systems at steady-state in a flexible and modular form, making it possible to investigate various cycle configurations with different working fluids. The code is based on unit subroutines containing the governing equations for the system''s components. When all the equations have been established, a mathematical solver routine is employed to solve them simultaneously. Property subroutines contained in a separate data base serve to provide thermodynamicmore » properties of the working fluids. The code is user-oriented and requires a relatively simple input containing the given operating conditions and the working fluid at each state point. the user conveys to the computer an image of the cycle by specifying the different components and their interconnections. Based on this information, the program calculates the temperature, flowrate, concentration, pressure and vapor fraction at each state point in the system and the heat duty at each unit, from which the coefficient of performance may be determined. A graphical user-interface is provided to facilitate interactive input and study of the output.« less

  14. A joint model for the emission and absorption properties of damped Lyα absorption systems

    NASA Astrophysics Data System (ADS)

    Barnes, Luke A.; Haehnelt, Martin G.

    2009-07-01

    The recently discovered population of ultra-faint extended line emitters, with fluxes of a few times 10-18ergs-1cm-2 at z ~ 3, can account for the majority of the incidence rate of damped Lyα systems (DLAs) at this redshift if the line emission is interpreted as Lyα. We show here that a model similar to that proposed by Haehnelt, Steinmetz & Rauch (2000), which reproduces the incidence rate and kinematics of DLAs in the context of Λ cold dark matter models for structure formation, also reproduces the size distribution of the new population of faint Lyα emitters for plausible parameters. This lends further support to the interpretation of the emission as Lyα, as well as the identification of the emitters with the hitherto elusive population of DLA host galaxies. The observed incidence rate of DLAs together with the observed space density and size distribution of the emitters suggest a duty cycle of ~0.2-0.4 for the Lyα emission from DLA host galaxies. We further show that Lyα cooling is expected to contribute little to the Lyα emission for the majority of emitters. This leaves centrally concentrated star formation at a rate of a few tenths Msolaryr-1, surrounded by extended Lyα haloes with radii up to 30-50 kpc, as the most plausible explanation for the origin of the emission. Both the luminosity function of Lyα emission and the velocity width distribution of low ionization absorption require that galaxies inside dark matter (DM) haloes with virial velocities <~50-70kms-1 contribute little to the incidence rate of DLAs at z ~ 3, suggesting that energy and momentum input due to star formation efficiently removes gas from these haloes. Galaxies with DM haloes with virial velocities of 100-150kms-1 appear to account for the majority of DLA host galaxies. DLA host galaxies at z ~ 3 should thus become the building blocks of typical present-day galaxies like our Milky Way.

  15. GSA's Green Proving Ground: Identifying, Testing and Evaluating Innovative Technologies (Presentation)

    SciTech Connect

    Kandt, A.; Lowell, M.

    2012-05-01

    GSA's Green Proving Ground (GPG) program utilizes GSA's real estate portfolio to test and evaluate innovative and underutilized sustainable building technologies and practices. Findings are used to support the development of GSA performance specifications and inform decision making within GSA, other federal agencies, and the real estate industry. The program aims to drive innovation in environmental performance in federal buildings and help lead market transformation through deployment of new technologies.

  16. Rapidly reconfigurable slow-light system based on off-resonant Raman absorption

    NASA Astrophysics Data System (ADS)

    Vudyasetu, Praveen K.; Camacho, Ryan M.; Howell, John C.

    2010-11-01

    We present a slow-light system based on dual Raman absorption resonances in warm rubidium vapor. Each Raman absorption resonance is produced by a control beam in an off-resonant Λ system. This system combines all optical control of the Raman absorption and the low-dispersion broadening properties of the double Lorentzian absorption slow light. The bandwidth, group delay, and central frequency of the slow-light system can all be tuned dynamically by changing the properties of the control beam. We demonstrate multiple pulse delays with low distortion and show that such a system has fast switching dynamics and thus fast reconfiguration rates.

  17. 41 CFR 102-37.490 - When must a SASP coordinate with GSA on compliance actions?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false When must a SASP coordinate with GSA on compliance actions? 102-37.490 Section 102-37.490 Public Contracts and Property... SASP coordinate with GSA on compliance actions? You must coordinate with GSA before selling...

  18. 41 CFR 101-28.202 - GSA/DOD cross-servicing agreement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true GSA/DOD cross-servicing... DISTRIBUTION 28.2-Interagency Cross-Servicing in Storage Activities § 101-28.202 GSA/DOD cross-servicing agreement. An agreement between GSA and DOD has established procedures to be followed in the...

  19. 41 CFR 101-28.202 - GSA/DOD cross-servicing agreement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false GSA/DOD cross-servicing... DISTRIBUTION 28.2-Interagency Cross-Servicing in Storage Activities § 101-28.202 GSA/DOD cross-servicing agreement. An agreement between GSA and DOD has established procedures to be followed in the...

  20. 41 CFR 101-28.202 - GSA/DOD cross-servicing agreement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true GSA/DOD cross-servicing... DISTRIBUTION 28.2-Interagency Cross-Servicing in Storage Activities § 101-28.202 GSA/DOD cross-servicing agreement. An agreement between GSA and DOD has established procedures to be followed in the...

  1. 41 CFR 101-28.202 - GSA/DOD cross-servicing agreement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true GSA/DOD cross-servicing... DISTRIBUTION 28.2-Interagency Cross-Servicing in Storage Activities § 101-28.202 GSA/DOD cross-servicing agreement. An agreement between GSA and DOD has established procedures to be followed in the...

  2. 41 CFR 101-28.202 - GSA/DOD cross-servicing agreement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 2 2011-07-01 2007-07-01 true GSA/DOD cross-servicing... DISTRIBUTION 28.2-Interagency Cross-Servicing in Storage Activities § 101-28.202 GSA/DOD cross-servicing agreement. An agreement between GSA and DOD has established procedures to be followed in the...

  3. 41 CFR 102-71.20 - What definitions apply to GSA's real property policies?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... to GSA's real property policies? 102-71.20 Section 102-71.20 Public Contracts and Property Management...-GENERAL § 102-71.20 What definitions apply to GSA's real property policies? The following definitions apply to GSA's real property policies: Airport means any area of land or water that is used, or...

  4. 75 FR 13131 - General Services Administration Acquisition Regulation; Submission for OMB Review; GSA Advantage...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-18

    ...! and Electronic Commerce- FACNET AGENCY: Office of the Chief Acquisition Officer, GSA. ACTION: Notice... collection requirement regarding GSA Advantage! and Electronic Commerce-FACNET. A request for public comments..., Washington, DC 20405. Please cite OMB Control No. 3090-00XX, GSA Advantage! and Electronic...

  5. 41 CFR 102-118.340 - How does my agency contact the GSA Audit Division?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... contact the GSA Audit Division? 102-118.340 Section 102-118.340 Public Contracts and Property Management... Approved Program § 102-118.340 How does my agency contact the GSA Audit Division? Your agency may contact the GSA Audit Division by writing to: General Services Administration, Transportation Audit...

  6. 41 CFR 102-33.380 - Who must report information to GSA on Government aircraft?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-33.380 Who must report information to GSA on Government aircraft? You must report information to GSA... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Who must report information to GSA on Government aircraft? 102-33.380 Section 102-33.380 Public Contracts and...

  7. 41 CFR 102-33.380 - Who must report information to GSA on Government aircraft?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...-33.380 Who must report information to GSA on Government aircraft? You must report information to GSA... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Who must report information to GSA on Government aircraft? 102-33.380 Section 102-33.380 Public Contracts and...

  8. 41 CFR 102-33.380 - Who must report information to GSA on Government aircraft?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...-33.380 Who must report information to GSA on Government aircraft? You must report information to GSA... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Who must report information to GSA on Government aircraft? 102-33.380 Section 102-33.380 Public Contracts and...

  9. 41 CFR 102-33.380 - Who must report information to GSA on Government aircraft?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...-33.380 Who must report information to GSA on Government aircraft? You must report information to GSA... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Who must report information to GSA on Government aircraft? 102-33.380 Section 102-33.380 Public Contracts and...

  10. Leveraging Lighting for Energy Savings: GSA Northwest/Artic Region

    SciTech Connect

    2016-01-01

    Case study describes how the Northwest/Arctic Region branch of the General Services Administration (GSA) improved safety and energy efficiency in its Fairbanks Federal Building parking garage used by federal employees, U.S. Marshals, and the District Court. A 74% savings was realized by replacing 220 high-pressure sodium fixtures with 220 light-emitting diode fixtures.

  11. 48 CFR 41.204 - GSA areawide contracts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... entire geographical area covered by an areawide contract, although it may be available at specific... information copy furnished to GSA at the address in 41.301(a). (2) Each areawide contract includes an... administrative requirements of the agency, applicable rate schedules, technical information and detailed maps...

  12. 48 CFR 41.204 - GSA areawide contracts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... entire geographical area covered by an areawide contract, although it may be available at specific... information copy furnished to GSA at the address in 41.301(a). (2) Each areawide contract includes an... administrative requirements of the agency, applicable rate schedules, technical information and detailed maps...

  13. 48 CFR 41.204 - GSA areawide contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... entire geographical area covered by an areawide contract, although it may be available at specific... information copy furnished to GSA at the address in 41.301(a). (2) Each areawide contract includes an... administrative requirements of the agency, applicable rate schedules, technical information and detailed maps...

  14. Membrane-Based Absorption Refrigeration Systems: Nanoengineered Membrane-Based Absorption Cooling for Buildings Using Unconcentrated Solar & Waste Heat

    SciTech Connect

    2010-09-01

    BEETIT Project: UFL is improving a refrigeration system that uses low quality heat to provide the energy needed to drive cooling. This system, known as absorption refrigeration system (ARS), typically consists of large coils that transfer heat. Unfortunately, these large heat exchanger coils are responsible for bulkiness and high cost of ARS. UFL is using new materials as well as system design innovations to develop nanoengineered membranes to allow for enhanced heat exchange that reduces bulkiness. UFL’s design allows for compact, cheaper and more reliable use of ARS that use solar or waste heat.

  15. CO Emission from Low-Redshift QSO Absorption Line Systems

    NASA Astrophysics Data System (ADS)

    Walker, C. E.; Bechtold, J.; Black, J. H.

    1994-12-01

    By studying the physical conditions in galaxies at different redshifts, we can begin to understand the evolutionary process of starformation from early epochs to the present. Such studies have been performed at optical and centimeter wavelengths for a number of years. Due to advances in receiver and telescope technology at millimeter and submillimeter wavelengths, molecular line studies have recently been performed toward high redshift absorption line systems. Observations of the mm/submm CO lines in these very young galaxies provide a way to investigate abundances of and conditions in potential starforming material. CO provides some of the strongest emission lines associated with star formation in nearby disk galaxies. Here we report the detection of CO in emission toward 4 galaxies at redshifts of 0.02 to 0.40. From these observations we are able to compute the molecular mass of the starforming material. Studies of starformation in galaxies at low to mid-redshift ranges are important, because these systems represent a transitional phase between starformation at early epochs and the present. Our recent detections of CO emission indicate total molecular masses in three of the galaxies to be a few times 10(9) Msun, using the ``standard conversion factor'' for molecular hydrogen column density to integrated CO intensity ratio (N(H_2)/Ico) and an H_o=75km/s/Mpc and q_o= 0.5. The fourth system, the z=0.40 21 cm absorber toward PKS 1229-021, has a molecular mass of ~ 10(11) M_sunh(-2) . Together with data at other wavelengths, the z=0.40 absorber may be a in pre-starburst phase. All four of our sources were selected to be metal line systems (with high HI column densities) and possess strong FIR fluxes detected by IRAS at 60 and/or 100{microns }. The source possessing the brightest FIR emission among the four is the z=0.05 21 cm absorber toward S4 0248+43. The total observed FIR luminosity for this source is LFIR =3.0x10E11 Lsun. Taking into account its luminosity and

  16. 41 CFR 302-1.102 - Are agencies required to report their employee relocation activities to GSA?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... report their employee relocation activities to GSA? 302-1.102 Section 302-1.102 Public Contracts and... employee relocation activities to GSA? Yes, every agency that spends more than $5 million a year on travel... survey year, must annually report their employee relocation activities to GSA. GSA works with...

  17. 41 CFR 302-1.102 - Are agencies required to report their employee relocation activities to GSA?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... report their employee relocation activities to GSA? 302-1.102 Section 302-1.102 Public Contracts and... employee relocation activities to GSA? Yes, every agency that spends more than $5 million a year on travel... survey year, must annually report their employee relocation activities to GSA. GSA works with...

  18. 41 CFR 102-85.215 - What if another customer agency forces a GSA customer to move?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What if another customer... § 102-85.215 What if another customer agency forces a GSA customer to move? If a GSA customer agency, or GSA, forces the relocation of another GSA customer agency prior to the expiration of the customer's...

  19. 41 CFR 102-75.1150 - What happens to the gift if GSA determines it to be acceptable?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... if GSA determines it to be acceptable? 102-75.1150 Section 102-75.1150 Public Contracts and Property...-75.1150 What happens to the gift if GSA determines it to be acceptable? When GSA determines that the gift is acceptable and can be accepted and used in the form in which it was offered, GSA must...

  20. Photoacoustic Experimental System to Confirm Infrared Absorption Due to Greenhouse Gases

    ERIC Educational Resources Information Center

    Kaneko, Fumitoshi; Monjushiro, Hideaki; Nishiyama, Masayoshi; Kasai, Toshio; Harris, Harold H.

    2010-01-01

    An experimental system for detecting infrared absorption using the photoacoustic (PA) effect is described. It is aimed for use at high-school level to illustrate the difference in infrared (IR) absorption among the gases contained in the atmosphere in connection with the greenhouse effect. The experimental system can be built with readily…

  1. The effect of age on systemic absorption and systemic disposition of bupivacaine after subarachnoid administration

    SciTech Connect

    Veering, B.T.; Burm, A.G.; Vletter, A.A.; van den Hoeven, R.A.; Spierdijk, J. )

    1991-02-01

    In order to evaluate the role of the pharmacokinetics of the age-related changes in the clinical profile of spinal anesthesia with bupivacaine, we studied the influence of age on the systemic absorption and systemic disposition of bupivacaine after subarachnoid administration in 20 male patients (22-81 yr), ASA Physical Status 1 or 2, by a stable isotope method. After subarachnoid administration of 3 ml 0.5% bupivacaine in 8% glucose, a deuterium-labeled analog (13.4 mg) was administered intravenously. Blood samples were collected for 24 h. Plasma concentrations of unlabeled and deuterium-labeled bupivacaine were determined with a combination of gas chromatography and mass fragmentography. Biexponential functions were fitted to the plasma concentration-time data of the deuterium-labeled bupivacaine. The systemic absorption was evaluated by means of deconvolution. Mono- and biexponential functions were fitted to the data of fraction absorbed versus time. The maximal height of analgesia and the duration of analgesia at T12 increased with age (r = 0.715, P less than 0.001; r = 0.640, P less than 0.01, respectively). In 18 patients the systemic absorption of bupivacaine was best described by a biexponential equation. The half-life of the slow systemic absorption process (r = -0.478; P less than 0.05) and the mean absorption time (r = -0.551; P less than 0.02) decreased with age. The total plasma clearance decreased with age (r = -0.650, P less than 0.002), whereas the mean residence time and terminal half-life increased with age (r = 0.597, P less than 0.01; r = 0.503, P less than 0.05).

  2. Nanocavity absorption enhancement for two-dimensional material monolayer systems.

    PubMed

    Song, Haomin; Jiang, Suhua; Ji, Dengxin; Zeng, Xie; Zhang, Nan; Liu, Kai; Wang, Chu; Xu, Yun; Gan, Qiaoqiang

    2015-03-23

    Here we propose a strategy to enhance the light-matter interaction of two-dimensional (2D) material monolayers based on strong interference effect in planar nanocavities, and overcome the limitation between optical absorption and the atomically-thin thickness of 2D materials. By exploring the role of spacer layers with different thicknesses and refractive indices, we demonstrate that a nanocavity with an air spacer layer placed between a graphene monolayer and an aluminum reflector layer will enhance the exclusive absorption in the graphene monolayer effectively, which is particularly useful for the development of atomically-thin energy harvesting/conversion devices.

  3. The -145 km/S Absorption System of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Vieira, G.; Gull, T. R.; Danks, A.; Johansson, S.

    2002-01-01

    With the STIS E230H mode (R-118,000) , we have identified about twenty absorption components in line of sight from Eta Carinae. Two components, one at -513 km/s and another at -145 W s , are quite different in character from the others, mostly at intermediate velocities. The -145 km/s component is significantly wider in fwhm, is seen in many more species, and the lower level can be above 20,000/cm, well above the 2000/cm noted in the -513 km/s component. In the spectral region from 2400 to 3160A, approximately 500 absorption lines have been identified. In this poster, we will present line identifications and atomic parameters of the measured lines, hopefully providing insight as to what levels are being excited and by what processes.

  4. The -145 km/s Absorption System of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Vieira, G.; Gull, Theodore R.; Danks, A.; Johansson, S.

    2002-01-01

    With the STIS E230H mode (R approx. 118,000), we have identified about twenty absorption components in line of sight from Eta Carinae. Two components, one at -513 km/s and another at -145 km/s, are quite different in character from the others, mostly at intermediate velocities. The -145 km/s component is significantly wider in fwhm, is seen in many more species, and the lower level can be above 20,000/cm, well above the 2000/cm noted in the -513 km/s component. In the spectral region from 2400 to 3160A, approximately 500 absorption lines have been identified. In this poster, we will present line identifications and atomic parameters of the measured lines, hopefully providing insight as to what levels are being excited and by what processes. Observations were accomplished through STScI under proposal 9242. Funding is through the STIS GTO resources.

  5. GSAFold: a new application of GSA to protein structure prediction.

    PubMed

    Melo, Marcelo C R; Bernardi, Rafael C; Fernandes, Tácio V A; Pascutti, Pedro G

    2012-08-01

    The folding process defines three-dimensional protein structures from their amino acid chains. A protein's structure determines its activity and properties; thus knowing such conformation on an atomic level is essential for both basic and applied studies of protein function and dynamics. However, the acquisition of such structures by experimental methods is slow and expensive, and current computational methods mostly depend on previously known structures to determine new ones. Here we present a new software called GSAFold that applies the generalized simulated annealing (GSA) algorithm on ab initio protein structure prediction. The GSA is a stochastic search algorithm employed in energy minimization and used in global optimization problems, especially those that depend on long-range interactions, such as gravity models and conformation optimization of small molecules. This new implementation applies, for the first time in ab initio protein structure prediction, an analytical inverse for the Visitation function of GSA. It also employs the broadly used NAMD Molecular Dynamics package to carry out energy calculations, allowing the user to select different force fields and parameterizations. Moreover, the software also allows the execution of several simulations simultaneously. Applications that depend on protein structures include rational drug design and structure-based protein function prediction. Applying GSAFold in a test peptide, it was possible to predict the structure of mastoparan-X to a root mean square deviation of 3.00 Å. PMID:22622959

  6. Contract and beyond GEMnet status and accomplishments: GSA's energy and maintenance network

    SciTech Connect

    Piette, Mary Ann; Kinney, Satkartar; Levi, Mark; McBride, David; May, Stephen

    2002-05-01

    The U.S. General Services Administration Pacific Rim Region (Region 9), manages over 20 million gross square feet of federally owned office space, plus additional leased office space, for the federal government in California, Nevada, Arizona, Hawaii and the Pacific territories. To assist in this real estate management the Pacific Rim Region is developing the GSA Energy and Maintenance Network, or GEMnet. GEMnet is a collection of information technology initiatives, including remote monitoring and control to reduce operational costs by improving energy efficiency, reducing peak demand, and optimizing maintenance in buildings. Ultimately the various systems use a common database platform. This paper describes the status and plans for GEMnet, focusing on how it compares with related monitoring and information technology currently used in nonresidential buildings. This paper will also report on recent activities within the GEMnet purview, demand-shedding and retro-commissioning. For example, two large GSA office buildings in the San Francisco Bay Area participated in the California Independent System Operator (ISO) demand relief program (DRP) during the summer of 2001, shedding nearly 1 MW when called upon. In conjunction with the fielding of GEMnet related programs, a series of retro-commissioning projects is being implemented, scoped to the needs of particular buildings. Details on the BAS retro-commissioning at one building is presented.

  7. The -145 km/s Absorption System of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Vieira, G. L.; Gull, T. R.; Danks, A. C.; Johansson, S.

    2002-12-01

    With the STIS E230H mode (R 118,000), we have identified about twenty absorption components in line of sight from Eta Carinae. Two components, one at -513 km/s and another at -145 km/s, are quite different in character from the others, mostly at intermediate velocities (See adjacent posters by T. Gull and A. Danks). The -145 km/s component is significantly wider in fwhm, is seen in many more species, and the lower level can be above 20,000 cm-1, well above the 2000 cm-1 noted in the -513 km/s component. In the spectral region from 2400 to 3160A, approximately 500 absorption lines have been identified. In this poster, we will present line identifications and atomic parameters of the measured lines, hopefully providing insight as to what levels are being excited and by what processes. Observations were accomplished through STScI under proposal 9242 (Danks, P.I.). Funding is through the STIS GTO resources.

  8. 41 CFR 102-34.335 - How do I submit information to the General Services Administration (GSA) for the Federal Fleet...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... through the Federal Automotive Statistical Tool (FAST), an Internet-based reporting tool. To find out how to submit motor vehicle data to GSA through FAST, consult the instructions from your agency fleet...; and (5) Fuel used. Note to § 102-34.335: The FAST system is also used by agency Fleet Managers...

  9. 41 CFR 102-34.220 - What does GSA do if it learns of unofficial use of a Government motor vehicle?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE MANAGEMENT Official Use of Government Motor Vehicles § 102-34... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false What does GSA do if...

  10. 41 CFR 300-90.5 - What factors will GSA consider in approving a request for a telework travel test program?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... consider in approving a request for a telework travel test program? 300-90.5 Section 300-90.5 Public Contracts and Property Management Federal Travel Regulation System GENERAL AGENCY REQUIREMENTS 90-TELEWORK TRAVEL EXPENSES TEST PROGRAMS § 300-90.5 What factors will GSA consider in approving a request for...

  11. Organic Carbon and Light Absorption Analysis of Los Angeles Aerosols through an Online Sampling System

    NASA Astrophysics Data System (ADS)

    Hartley, M. K.; Hawkins, L. N.

    2013-12-01

    Brown carbon is a comprehensive term for organic compounds with wavelength dependent light absorption. Common sources of brown carbon include fossil fuel combustion, biomass burning and aqueous reactions in cloud and fog water. Nitrophenols have been proposed as one source of brown carbon in the Los Angeles area. In this work, we are interested in the relative strengths of each of these sources within Los Angeles. We have implemented a continuous online system of collection and analysis within our lab. The system consists of a particle into liquid sampler (PILS), a liquid waveguide capillary cell (LWCC) and a total organic carbon analyzer (TOC). Online analysis of organic carbon content and UV-Vis absorption has allowed us to study the ratio of the two as an intrinsic property of the aerosol particles, called the 'absorption coefficient.' Using a rearrangement of Beer's Law, we have analyzed the relationship: ɛ = A / C (where ɛ is the absorption coefficient, A is the light absorption of the sample and C is the concentration of organic carbon in the sample). Using our continuous online system, we have collected absorption spectra and total organic carbon measurements over several weeks and in varying environmental conditions. Our work has shown that different weather conditions, along with fog or cloud formation, can affect the absorption coefficient of the brown carbon compounds in the air.

  12. In vitro and in vivo percutaneous absorption of retinol from cosmetic formulations: Significance of the skin reservoir and prediction of systemic absorption

    SciTech Connect

    Yourick, Jeffrey J. Jung, Connie T.; Bronaugh, Robert L.

    2008-08-15

    The percutaneous absorption of retinol (Vitamin A) from cosmetic formulations was studied to predict systemic absorption and to understand the significance of the skin reservoir in in vitro absorption studies. Viable skin from fuzzy rat or human subjects was assembled in flow-through diffusion cells for in vitro absorption studies. In vivo absorption studies using fuzzy rats were performed in glass metabolism cages for collection of urine, feces, and body content. Retinol (0.3%) formulations (hydroalcoholic gel and oil-in-water emulsion) containing {sup 3}H-retinol were applied and absorption was measured at 24 or 72 h. All percentages reported are % of applied dose. In vitro studies using human skin and the gel and emulsion vehicles found 0.3 and 1.3% retinol, respectively, in receptor fluid at 24 h. Levels of absorption in the receptor fluid increased over 72 h with the gel and emulsion vehicles. Using the gel vehicle, in vitro rat skin studies found 23% in skin and 6% in receptor fluid at 24 h, while 72-h studies found 18% in skin and 13% in receptor fluid. Thus, significant amounts of retinol remained in rat skin at 24 h and decreased over 72 h, with proportional increases in receptor fluid. In vivo rat studies with the gel found 4% systemic absorption of retinol after 24 h and systemic absorption did not increase at 72 h. Retinol remaining in rat skin after in vivo application was 18% and 13% of the applied dermal dose after 24 and 72 h, respectively. Similar observations were made with the oil-in water emulsion vehicle in the rat. Retinol formed a reservoir in rat skin both in vivo and in vitro. Little additional retinol was bioavailable after 24 h. Comparison of these in vitro and in vivo results for absorption through rat skin indicates that the 24-h in vitro receptor fluid value accurately estimated 24-h in vivo systemic absorption. Therefore, the best single estimate of retinol systemic absorption from in vitro human skin studies is the 24-h receptor

  13. High frequency ultrasonic-assisted CO2 absorption in a high pressure water batch system.

    PubMed

    Tay, W H; Lau, K K; Shariff, A M

    2016-11-01

    Physical absorption process is always nullified by the presence of cavitation under low frequency ultrasonic irradiation. In the present study, high frequency ultrasonic of 1.7MHz was used for the physical absorption of CO2 in a water batch system under elevated pressure. The parameters including ultrasonic power and initial feed pressure for the system have been varied from 0 to 18W and 6 to 41bar, respectively. The mass transfer coefficient has been determined via the dynamic pressure-step method. Besides, the actual ultrasonic power that transmitted to the liquid was measured based on calorimetric method prior to the absorption study. Subsequently, desorption study was conducted as a comparison with the absorption process. The mechanism for the ultrasonic assisted absorption has also been discussed. Based on the results, the mass transfer coefficient has increased with the increasing of ultrasonic power. It means that, the presence of streaming effect and the formation of liquid fountain is more favorable under high frequency ultrasonic irradiation for the absorption process. Therefore, high frequency ultrasonic irradiation is suggested to be one of the potential alternatives for the gas separation process with its promising absorption enhancement and compact design. PMID:27245970

  14. High frequency ultrasonic-assisted CO2 absorption in a high pressure water batch system.

    PubMed

    Tay, W H; Lau, K K; Shariff, A M

    2016-11-01

    Physical absorption process is always nullified by the presence of cavitation under low frequency ultrasonic irradiation. In the present study, high frequency ultrasonic of 1.7MHz was used for the physical absorption of CO2 in a water batch system under elevated pressure. The parameters including ultrasonic power and initial feed pressure for the system have been varied from 0 to 18W and 6 to 41bar, respectively. The mass transfer coefficient has been determined via the dynamic pressure-step method. Besides, the actual ultrasonic power that transmitted to the liquid was measured based on calorimetric method prior to the absorption study. Subsequently, desorption study was conducted as a comparison with the absorption process. The mechanism for the ultrasonic assisted absorption has also been discussed. Based on the results, the mass transfer coefficient has increased with the increasing of ultrasonic power. It means that, the presence of streaming effect and the formation of liquid fountain is more favorable under high frequency ultrasonic irradiation for the absorption process. Therefore, high frequency ultrasonic irradiation is suggested to be one of the potential alternatives for the gas separation process with its promising absorption enhancement and compact design.

  15. A study of energy absorption rate in a quantum dot and metallic nanosphere hybrid system.

    PubMed

    Schindel, Daniel; Singh, Mahi R

    2015-09-01

    We have studied energy absorption rate in a quantum dot-metallic nanosphere system embedded on a dielectric substrate. We applied a control field to induce dipole moments in the quantum dot and the metal nanosphere, and monitored the energy absorption using a probe field. These external fields induce dipole moments in the metal nanosphere and the quantum dot, and these two structures interact with one another via the dipole-dipole interaction. The density matrix method was used to evaluate the absorption, indicating that it can be shifted by moving the metal nanosphere close to the quantum dot. Also, absorption efficiency can either be quenched or enhanced by the addition of a metal nanosphere. This hybrid system can be used to create ultrafast switching and sensing nanodevices.

  16. A study of energy absorption rate in a quantum dot and metallic nanosphere hybrid system

    NASA Astrophysics Data System (ADS)

    Schindel, Daniel; Singh, Mahi R.

    2015-09-01

    We have studied energy absorption rate in a quantum dot-metallic nanosphere system embedded on a dielectric substrate. We applied a control field to induce dipole moments in the quantum dot and the metal nanosphere, and monitored the energy absorption using a probe field. These external fields induce dipole moments in the metal nanosphere and the quantum dot, and these two structures interact with one another via the dipole-dipole interaction. The density matrix method was used to evaluate the absorption, indicating that it can be shifted by moving the metal nanosphere close to the quantum dot. Also, absorption efficiency can either be quenched or enhanced by the addition of a metal nanosphere. This hybrid system can be used to create ultrafast switching and sensing nanodevices.

  17. Software system for numerical simulation of minor gas constituents lidar sensing by the differential absorption method

    NASA Astrophysics Data System (ADS)

    Bochkovskii, D. A.; Matvienko, G. G.; Romanovskii, O. A.; Kharchenko, O. V.; Yakovlev, S. V.

    2014-11-01

    This paper reports the development of LIDAS (LIdar Differential Absorption Sensing) program-algorithmic system for laser remote sensing of minor gas constituents (MGCs) of the atmosphere by the differential absorption method (DIAL). The system includes modules for the search of wavelengths informative for laser gas analysis by the differential absorption method, for numerical simulation of lidar sensing of atmospheric MGCs, and for calculation of errors of methodical, atmospheric, spectral, and instrumental origin. Lidar sensing of gas constituents by the differential absorption method as applied to problems of sensing of atmospheric MGCs is simulated numerically. Results of experiments on remote sensing of gas constituents of the atmosphere with the use of RO laser are presented.

  18. Transient dispersion and absorption in a V-shaped atomic system

    NASA Astrophysics Data System (ADS)

    Sahrai, M.; Maleki, A.; Hemmati, R.; Mahmoudi, M.

    2010-01-01

    We investigate the dynamical behavior of the dispersion and the absorption in a V-type three level atomic system. It is shown that in the presence of decay-induced interference the probe dispersion and absorption are phase dependent. We find that an incoherent pumping field provides an additional control parameter for switching the group velocity of a light pulse. The required switching times for switching the group velocity of a probe field from subluminal to superluminal pulse propagation is then discussed.

  19. 41 CFR 102-192.90 - What must we include in our annual mail management report to GSA?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... publication called “Marketips,” which provides information about supplies and services available through GSA... regard. Note to § 102-192.90: GSA is launching a long-term initiative to improve the usefulness of...

  20. 41 CFR 101-26.4902-1781 - GSA Form 1781, Motor Vehicle Requisition-Delivery Order.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true GSA Form 1781, Motor Vehicle Requisition-Delivery Order. 101-26.4902-1781 Section 101-26.4902-1781 Public Contracts and... GSA Form 1781, Motor Vehicle Requisition—Delivery Order. Note: The form illustrated in §...

  1. 41 CFR 102-35.15 - What are the goals of GSA's personal property regulations?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What are the goals of... PROPERTY 35-DISPOSITION OF PERSONAL PROPERTY § 102-35.15 What are the goals of GSA's personal property regulations? The goals of GSA's personal property regulations are to: (a) Improve the identification...

  2. 45 CFR 12a.5 - Real property reported excess to GSA.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... determine interest in the property in accordance with current regulations. (See 41 CFR 101-47.203-5, 101-47... protect and maintain any property which is reported excess to GSA as provided in 41 CFR 101-47.402. ... in § 12a.5(e). In lieu of the above, GSA may submit a new checklist to HUD and follow the...

  3. 24 CFR 581.5 - Real property reported excess to GSA.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... property in accordance with current regulations. (See 41 CFR 101-47.203-5, 101-47.204-1 and 101-47.303-2... property which is reported excess to GSA as provided in 41 CFR 101-47.402. ... above, GSA may submit a new checklist to HUD and follow the procedures in § 581.5(c) through §...

  4. 24 CFR 581.5 - Real property reported excess to GSA.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... property in accordance with current regulations. (See 41 CFR 101-47.203-5, 101-47.204-1 and 101-47.303-2... property which is reported excess to GSA as provided in 41 CFR 101-47.402. ... above, GSA may submit a new checklist to HUD and follow the procedures in § 581.5(c) through §...

  5. 45 CFR 12a.5 - Real property reported excess to GSA.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... determine interest in the property in accordance with current regulations. (See 41 CFR 101-47.203-5, 101-47... protect and maintain any property which is reported excess to GSA as provided in 41 CFR 101-47.402. ... in § 12a.5(e). In lieu of the above, GSA may submit a new checklist to HUD and follow the...

  6. 41 CFR 102-37.90 - What are GSA's responsibilities in the donation of surplus property?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... responsibilities in the donation of surplus property? 102-37.90 Section 102-37.90 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY General Services Administration (GSA) § 102-37.90 What are GSA's responsibilities in the donation of surplus property? The General Services...

  7. 77 FR 15759 - Information Collection; Federal Management Regulation; GSA Form 3040, State Agency Monthly...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-16

    ... Donation Report of Surplus Property AGENCY: Federal Acquisition Service, GSA. ACTION: Notice of request for... regarding GSA Form 3040, State Agency Monthly Donation Report of Surplus Property. Public comments are..., State Agency Monthly Donation Report of Surplus Personal Property by any of the following...

  8. 41 CFR 102-37.90 - What are GSA's responsibilities in the donation of surplus property?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... responsibilities in the donation of surplus property? 102-37.90 Section 102-37.90 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY General Services Administration (GSA) § 102-37.90 What are GSA's responsibilities in the donation of surplus property? The General Services...

  9. 41 CFR 102-75.299 - What are landholding agencies' responsibilities if GSA conducts the disposal?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... agencies' responsibilities if GSA conducts the disposal? 102-75.299 Section 102-75.299 Public Contracts and... REGULATION REAL PROPERTY 75-REAL PROPERTY DISPOSAL Surplus Real Property Disposal Designation of Disposal Agencies § 102-75.299 What are landholding agencies' responsibilities if GSA conducts the...

  10. 41 CFR 101-26.503 - Multiple award schedule purchases made by GSA supply distribution facilities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Multiple award schedule... Multiple award schedule purchases made by GSA supply distribution facilities. GSA supply distribution... items. Stocking a variety of commercial, high-demand items purchased from FSS multiple award...

  11. 41 CFR 105-60.305-4 - GSA records available at a fee.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false GSA records available at a fee. 105-60.305-4 Section 105-60.305-4 Public Contracts and Property Management Federal Property..., Orders, Policies, Interpretations, Manuals, and Instructions § 105-60.305-4 GSA records available at...

  12. 41 CFR 102-33.40 - What are GSA's responsibilities for Federal aviation management?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... responsibilities for Federal aviation management? 102-33.40 Section 102-33.40 Public Contracts and Property... GSA's responsibilities for Federal aviation management? Under OMB Circular A-126, “Improving the.../omb), GSA's chief responsibilities for Federal aviation management are to maintain— (a) A...

  13. 41 CFR 102-33.40 - What are GSA's responsibilities for Federal aviation management?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... responsibilities for Federal aviation management? 102-33.40 Section 102-33.40 Public Contracts and Property... GSA's responsibilities for Federal aviation management? Under OMB Circular A-126, “Improving the.../omb), GSA's chief responsibilities for Federal aviation management are to maintain— (a) A...

  14. 41 CFR 102-33.40 - What are GSA's responsibilities for Federal aviation management?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... responsibilities for Federal aviation management? 102-33.40 Section 102-33.40 Public Contracts and Property... GSA's responsibilities for Federal aviation management? Under OMB Circular A-126, “Improving the.../omb), GSA's chief responsibilities for Federal aviation management are to maintain— (a) A...

  15. 41 CFR 102-33.40 - What are GSA's responsibilities for Federal aviation management?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... responsibilities for Federal aviation management? 102-33.40 Section 102-33.40 Public Contracts and Property... GSA's responsibilities for Federal aviation management? Under OMB Circular A-126, “Improving the.../omb), GSA's chief responsibilities for Federal aviation management are to maintain— (a) A...

  16. 41 CFR 102-33.40 - What are GSA's responsibilities for Federal aviation management?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... responsibilities for Federal aviation management? 102-33.40 Section 102-33.40 Public Contracts and Property... GSA's responsibilities for Federal aviation management? Under OMB Circular A-126, “Improving the.../omb), GSA's chief responsibilities for Federal aviation management are to maintain— (a) A...

  17. 41 CFR 102-36.275 - May we dispose of excess personal property without GSA approval?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...) You may dispose of excess personal property without going through GSA when such disposal is authorized..., you may not dispose of excess personal property without GSA approval except under the following limited situations: (a) You may transfer to another federal agency excess personal property that has...

  18. 41 CFR 102-36.275 - May we dispose of excess personal property without GSA approval?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) You may dispose of excess personal property without going through GSA when such disposal is authorized..., you may not dispose of excess personal property without GSA approval except under the following limited situations: (a) You may transfer to another federal agency excess personal property that has...

  19. 41 CFR 102-36.275 - May we dispose of excess personal property without GSA approval?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) You may dispose of excess personal property without going through GSA when such disposal is authorized..., you may not dispose of excess personal property without GSA approval except under the following limited situations: (a) You may transfer to another federal agency excess personal property that has...

  20. 41 CFR 102-36.275 - May we dispose of excess personal property without GSA approval?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) You may dispose of excess personal property without going through GSA when such disposal is authorized..., you may not dispose of excess personal property without GSA approval except under the following limited situations: (a) You may transfer to another federal agency excess personal property that has...

  1. 41 CFR 102-36.275 - May we dispose of excess personal property without GSA approval?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) You may dispose of excess personal property without going through GSA when such disposal is authorized..., you may not dispose of excess personal property without GSA approval except under the following limited situations: (a) You may transfer to another federal agency excess personal property that has...

  2. 78 FR 22880 - Privacy Act of 1974; Notice of cancellation of System of Record Notice (SORN)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-17

    ... (SAM). The (SORN) was published in the Federal Register at 73 FR 22374 on Friday, April 25, 2008. Dated... Services Administration (GSA). ACTION: Withdrawal of GSA/GOV-8 Excluded Parties List System (EPLS) System...: GSA/GOV-8 Excluded Parties List System (EPLS). DATES: Effective Date: April 17, 2013. FOR...

  3. [The Research for Trace Ammonia Escape Monitoring System Based on Tunable Diode Laser Absorption Spectroscopy].

    PubMed

    Zhang, Li-fang; Wang, Fei; Yu, Li-bin; Yan, Jian-hua; Cen, Ke-fa

    2015-06-01

    In order to on-line measure the trace ammonia slip of the commercial power plant in the future, this research seeks to measure the trace ammonia by using tunable diode laser absorption spectroscopy under ambient temperature and pressure, and at different temperatures, and the measuring temperature is about 650 K in the power plant. In recent years lasers have become commercially available in the near-infrared where the transitions are much stronger, and ammonia's spectroscopy is pretty complicated and the overlapping lines are difficult to resolve. A group of ammonia transitions near 4 433.5 cm(-1) in the v2 +v3 combination band have been thoroughly selected for detecting lower concentration by analyzing its absorption characteristic and considering other absorption interference in combustion gases where H2O and CO2 mole fraction are very large. To illustrate the potential for NH3 concentration measurements, predictions for NH3, H2O and CO2 are simultaneously simulated, NH3 absorption lines near 4 433.5 cm(-1) wavelength meet weaker H2O absorption than the commercial NH3 lines, and there is almost no CO2 absorption, all the parameters are based on the HITRAN database, and an improved detection limit was obtained for interference-free NH3 monitoring, this 2.25 μm band has line strengths several times larger than absorption lines in the 1.53 μm band which was often used by NH3 sensors for emission monitoring and analyzing. The measurement system was developed with a new Herriott cell and a heated gas cell realizing fast absorption measurements of high resolution, and combined with direct absorption and wavelenguh modulation based on tunable diode laser absorption spectroscopy at different temperatures. The lorentzian line shape is dominant at ambient temperature and pressure, and the estimated detectivity is approximately 0.225 x 10(-6) (SNR = 1) for the directed absorption spectroscopy, assuming a noise-equivalent absorbance of 1 x 10(-4). The heated cell

  4. Energy Savings from GSA's National Deep Retrofit Program

    SciTech Connect

    Shonder, John A

    2014-09-01

    Under its National Deep Energy Retrofit (NDER) program, the U.S. General Services Administration (GSA) awarded 10 ESPC projects with the objectives of using innovative technologies and renewable energy technologies, and moving buildings toward net zero energy consumption. This report analyzes data on energy savings from the 10 NDER projects, and compares them with the savings of a sample of other recently awarded Federal ESPC projects. It is shown that by emphasizing the need for deeper energy savings, and by the establishment of a central Project Management Office (PMO) to provide authoritative contracting, technical and pricing assistance, the NDER projects achieved an average level of savings more than twice that of the other Federal ESPC projects. The level of savings achieved in each project seems to be dependent more on the availability of ECMs at the site than on energy price, energy cost per square foot, pre-retrofit EUI or the length of the contract term. This suggests that GSA can achieve similar results in a wide variety of building

  5. Load-limiting landing gear footpad energy absorption system

    NASA Technical Reports Server (NTRS)

    Hansen, Chris; Tsai, Ted

    1994-01-01

    As a precursor to future manned missions to the moon, an inexpensive, unmanned vehicle that could carry small, scientific payloads to the lunar surface was studied by NASA. The vehicle, called the Common Lunar Lander, required extremely optimized structural systems to increase the potential payload mass. A lightweight energy-absorbing system (LAGFEAS), which also acts as a landing load-limiter was designed to help achieve this optimized structure. Since the versatile and easily tailored system is a load-limiter, it allowed for the structure to be designed independently of the ever-changing landing energy predictions. This paper describes the LAGFEAS system and preliminary verification testing performed at NASA's Johnson Space Center for the Common Lunar Lander program.

  6. Optimal extraction of quasar Lyman limit absorption systems from the IUE archive

    NASA Technical Reports Server (NTRS)

    Tytler, David

    1992-01-01

    The IUE archive contains a wealth of information on Lyman limit absorption systems (LLS) in quasar spectra. QSO spectra from the IUE data base were optimally extracted, coadded, and analyzed to yield a homogeneous samples of LLS at low red shifts. This sample comprise 36 LLS, twice the number previously analyzed low z samples. These systems are ideal for the determination of the origin, redshift evolution, ionization, velocity dispersions and the metal abundances of absorption systems. Two of them are also excellent targets for the primordial Deuterium to Hydrogen ratio.

  7. Analysis of a solar heat pipe heating and absorption cooling system

    NASA Astrophysics Data System (ADS)

    Munje, S. R.

    A new concept which combines a flat-plate heat-pipe solar collector for daytime solar water heating by evaporation of a refrigerant and night-time water chilling by absorption refrigeration was analyzed. A comprehensive survey of literature was completed to establish the existing state of knowledge on intermittent absorption refrigeration, flat-plate solar heat collectors and night sky radiation cooling. The literature survey showed that the idea of using a passive device such as a heat pipe with the absorption refrigeration principle for both heating and cooling is relatively new. A mathematical model for the heat-pipe flat-plate collector and the absorption refrigeration process was developed. A cost-effectiveness study was also carried out to find the optimum thickness of the collector plate. The optimum plate thickness was used in the parametric study of the system.

  8. 41 CFR 102-73.85 - Can agencies with independent statutory authority to lease space have GSA perform the leasing...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... independent statutory authority to lease space have GSA perform the leasing functions? 102-73.85 Section 102...-73.85 Can agencies with independent statutory authority to lease space have GSA perform the leasing functions? Yes, upon request, GSA may perform, on a reimbursable basis, all functions of leasing...

  9. 77 FR 38064 - Public Buildings Service; Information Collection; GSA Form 3453, Application/Permit for Use of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-26

    ... Space in Public Buildings and Grounds AGENCY: Public Buildings Service, GSA. ACTION: Notice of request... requirement regarding GSA Form 3453, Application/Permit for Use of Space in Public Buildings and Grounds... Information Collection 3090- 0044, GSA Form 3453, Application/Permit for Use of Space in Public Buildings...

  10. 48 CFR 339.7001 - Request for approval to make an award to other than a GSA BPA holder.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... make an award to other than a GSA BPA holder. 339.7001 Section 339.7001 Federal Acquisition Regulations... Services 339.7001 Request for approval to make an award to other than a GSA BPA holder. The Contracting... micro-purchase threshold, that obtaining the required services from a source other than a GSA BPA...

  11. 48 CFR 339.7001 - Request for approval to make an award to other than a GSA BPA holder.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... make an award to other than a GSA BPA holder. 339.7001 Section 339.7001 Federal Acquisition Regulations... Services 339.7001 Request for approval to make an award to other than a GSA BPA holder. The Contracting... micro-purchase threshold, that obtaining the required services from a source other than a GSA BPA...

  12. 48 CFR 339.7001 - Request for approval to make an award to other than a GSA BPA holder.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... make an award to other than a GSA BPA holder. 339.7001 Section 339.7001 Federal Acquisition Regulations... Services 339.7001 Request for approval to make an award to other than a GSA BPA holder. The Contracting... micro-purchase threshold, that obtaining the required services from a source other than a GSA BPA...

  13. 48 CFR 339.7001 - Request for approval to make an award to other than a GSA BPA holder.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... make an award to other than a GSA BPA holder. 339.7001 Section 339.7001 Federal Acquisition Regulations... Services 339.7001 Request for approval to make an award to other than a GSA BPA holder. The Contracting... micro-purchase threshold, that obtaining the required services from a source other than a GSA BPA...

  14. 48 CFR 339.7001 - Request for approval to make an award to other than a GSA BPA holder.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... make an award to other than a GSA BPA holder. 339.7001 Section 339.7001 Federal Acquisition Regulations... Services 339.7001 Request for approval to make an award to other than a GSA BPA holder. The Contracting... micro-purchase threshold, that obtaining the required services from a source other than a GSA BPA...

  15. 41 CFR 102-117.35 - What are the advantages and disadvantages of using GSA's tender of service?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What are the advantages...-117.35 What are the advantages and disadvantages of using GSA's tender of service? (a) It is an advantage to use GSA's tender of service when you want to: (1) Use GSA's authority to negotiate on behalf...

  16. 41 CFR 102-73.85 - Can agencies with independent statutory authority to lease space have GSA perform the leasing...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... lease space. However, GSA reserves the right to accept or reject reimbursable leasing service requests... independent statutory authority to lease space have GSA perform the leasing functions? 102-73.85 Section 102...-73.85 Can agencies with independent statutory authority to lease space have GSA perform the...

  17. Bicycle shock absorption systems and energy expended by the cyclist.

    PubMed

    Nielens, Henri; Lejeune, Thierry

    2004-01-01

    Bicycle suspension systems have been designed to improve bicycle comfort and handling by dissipating terrain-induced energy. However, they may also dissipate the cyclist's energy through small oscillatory movements, often termed 'bobbing', that are generated by the pedalling movements. This phenomenon is a major concern for competitive cyclists engaged in events where most of the time is spent climbing, e.g. off-road cross-country races. An acceptable method to assess the overall efficacy of suspension systems would be to evaluate energy consumed by cyclists using different types of suspension systems. It could be assumed that any system that reduces metabolic expenditure for the cyclist would automatically lead to performance improvement. Unfortunately, only a limited number of studies have been conducted on that subject. Moreover, the conclusions that can be drawn from most of them are limited due to unsatisfactory statistical power, experimental protocols, measuring techniques and equipment. This review presents and discusses the most relevant results of studies that focused on mechanical simulations as well as on energy expenditure in relation to off-road bicycle suspension systems. Evidence in the literature suggests that cyclist-generated power that is dissipated by suspensions is minimal and probably negligible on most terrains. However, the scarce studies on the topic as well as the limitations in the conclusions that can be drawn from most of them indicate that we should remain cautious before supporting the use of dual suspension bicycles on all course types and for all cyclists. For example, it should be kept in mind that most cross-country racers still use front suspension bicycles. This might be explained by excessive cyclist-generated power dissipation at the high mechanical powers developed by elite cross-country cyclists that have not been studied in the literature. Finally, suspended bicycles are more comfortable. Moreover, the fact that suspension

  18. Prototype explosives detection system based on nuclear resonance absorption in nitrogen

    SciTech Connect

    Morgado, R.E.; Arnone, G.; Cappiello, C.C.; Gardner, S.D.; Hollas, C.L.; Ussery, L.E.; White, J.M.; Zahrt, J.D.; Krauss, R.A.

    1993-12-01

    A-prototype explosives detection system that was developed for experimental evaluation of a nuclear resonance absorption techniques is described. The major subsystems are a proton accelerator and beam transport, high-temperature proton target, an airline-luggage tomographic inspection station, and an image-processing/detection- alarm subsystem. The detection system performance, based on a limited experimental test, is reported.

  19. Prototype explosives-detection system based on nuclear-resonance absorption in nitrogen

    SciTech Connect

    Morgado, R.E.; Arnone, G.; Cappiello, C.C.; Gardner, S.D.; Hollas, C.L.; Ussery, L.E.; White, J.M.; Zahrt, J.D.; Krauss, R.A.

    1994-06-01

    A prototype explosives-detection system (EDS) that was developed for experimental evaluation of a nuclear-resonance absorption technique is described. The major subsystems are a proton accelerator and beam transport, high-temperature proton target, an airline-luggage tomographic inspection station, and an image-processing/detection-alarm subsystem. The detection system performance, based on a limited experimental test, is reported.

  20. Temperature fields of an absorptive medium in a radiating system of arbitrary configuration (the spatial problem)

    NASA Technical Reports Server (NTRS)

    Surinov, Y. A.

    1975-01-01

    A generalized zonal method based on systems of linear algebraic equations is used to determine the temperature fields in an absorptive grey medium filling a closed radiation system that consists of three boundary zones, of which one is adiabatic and the other two are isothermal. The example calculation considers the case of a solenoidal radiation field of local radiative equilibrium.

  1. Thermodynamics and Kinetics of Deuterium Absorption in Scandium System

    NASA Astrophysics Data System (ADS)

    Wu, Qingying; Bing, Wenzeng; Long, Xinggui; Zhou, Xiaosong; Liu, Jinhua; Luo, Shunzhong

    2013-02-01

    Thermodynamic and kinetic characteristics of the Sc-D system are investigated as a complement to the earlier studies of the Sc-H system. A Sieverts apparatus is employed to conduct the measurements. The Sc-D system is characterized by two phase regions: the metal-rich and the deuteride phases. The equilibrium plateau relationships in the two-phase regions are determined from the Van't Hoff plots and found to be: . The enthalpy and entropy of reaction are calculated to be (-136.14 ± 1.57) kJ mol-1 D2 and (-100.06 ± 1.50) J mol-1 K-1 D2, respectively. From the relationship of ln[(P0-Pf)/(P-Pf)] and time t, the reaction of the Sc-D system is confirmed to be a first-order reaction in the temperature range of 923-1,073 K. The temperature has a negative effect on the reaction rate (ka), which decreases from 0.0717 to 0.0130 s-1 with the temperature increasing from 923 to 1,073 K. In addition, a minus activation energy of (-93.87 ± 6.22) kJ.mol-1 is acquired. However, once increasing temperature up to 1,123 K, the relationship of ln[(P0-Pf)/(P-Pf)] and time t firstly satisfies an exponential equation of y = -0.5471exp(-x/9.1879) + 0.00272. After 50 s, it begins fitting a linear equation again, indicating the various reaction mechanisms.

  2. Prototype explosives detection system based on nuclear resonance absorption in nitrogen

    SciTech Connect

    Morgado, R.E.; Arnone, G.J.; Cappiello, C.C.

    1996-05-01

    A laboratory prototype system has been developed for the experimental evaluation of an explosives detection technique based on nuclear resonance absorption of gamma rays in nitrogen. Major subsystems include a radiofrequency quadrupole proton accelerator and associated beam transport system, a high-power gamma-ray production target, an airline-luggage tomographic inspection system, and an image- processing/detection-alarm subsystem. The detection system performance, based on a limited experimental test, is reported.

  3. One- and two-photon absorption of a spiropyran-merocyanine system: experimental and theoretical studies.

    PubMed

    Matczyszyn, Katarzyna; Olesiak-Banska, Joanna; Nakatani, Keitaro; Yu, Pei; Murugan, N Arul; Zaleśny, Robert; Roztoczyńska, Agnieszka; Bednarska, Joanna; Bartkowiak, Wojciech; Kongsted, Jacob; Ågren, Hans; Samoć, Marek

    2015-01-29

    We report on the nonlinear optical properties measurements and quantum-chemical calculations of a well-known photochromic system consisting of spiropyran and the merocyanine photoproduct. The study of nonlinear absorption and refraction properties of the molecules dissolved in chloroform were performed with the Z-scan technique, using femtosecond pulses in a wide range of wavelengths. Maxima in the two-photon absorption spectrum at 700 and 1050 nm were found for the merocyanine form, and the corresponding two-photon absorption cross section is 80 GM and 20 GM, respectively. The latter feature does not vanish completely in the nonlinear spectrum of the spiropyran form, possibly because of the existence of some photoconversion caused by the laser beam during the measurements. A nonlinear absorption peak at 900 nm is found in the spiropyran form with an effective cross section of about 20 GM; it is likely due to three-photon absorption or to absorption by some intermediate species. The experimental data are supported by calculations performed with the use of a hybrid quantum mechanics-molecular mechanics approach. PMID:25531561

  4. Intestinal triacylglycerol synthesis in fat absorption and systemic energy metabolism.

    PubMed

    Yen, Chi-Liang Eric; Nelson, David W; Yen, Mei-I

    2015-03-01

    The intestine plays a prominent role in the biosynthesis of triacylglycerol (triglyceride; TAG). Digested dietary TAG is repackaged in the intestine to form the hydrophobic core of chylomicrons, which deliver metabolic fuels, essential fatty acids, and other lipid-soluble nutrients to the peripheral tissues. By controlling the flux of dietary fat into the circulation, intestinal TAG synthesis can greatly impact systemic metabolism. Genes encoding many of the enzymes involved in TAG synthesis have been identified. Among TAG synthesis enzymes, acyl-CoA:monoacylglycerol acyltransferase 2 and acyl-CoA:diacylglycerol acyltransferase (DGAT)1 are highly expressed in the intestine. Their physiological functions have been examined in the context of whole organisms using genetically engineered mice and, in the case of DGAT1, specific inhibitors. An emerging theme from recent findings is that limiting the rate of TAG synthesis in the intestine can modulate gut hormone secretion, lipid metabolism, and systemic energy balance. The underlying mechanisms and their implications for humans are yet to be explored. Pharmacological inhibition of TAG hydrolysis in the intestinal lumen has been employed to combat obesity and associated disorders with modest efficacy and unwanted side effects. The therapeutic potential of inhibiting specific enzymes involved in intestinal TAG synthesis warrants further investigation. PMID:25231105

  5. Intestinal triacylglycerol synthesis in fat absorption and systemic energy metabolism

    PubMed Central

    Yen, Chi-Liang Eric; Nelson, David W.; Yen, Mei-I

    2015-01-01

    The intestine plays a prominent role in the biosynthesis of triacylglycerol (triglyceride; TAG). Digested dietary TAG is repackaged in the intestine to form the hydrophobic core of chylomicrons, which deliver metabolic fuels, essential fatty acids, and other lipid-soluble nutrients to the peripheral tissues. By controlling the flux of dietary fat into the circulation, intestinal TAG synthesis can greatly impact systemic metabolism. Genes encoding many of the enzymes involved in TAG synthesis have been identified. Among TAG synthesis enzymes, acyl-CoA:monoacylglycerol acyltransferase 2 and acyl-CoA:diacylglycerol acyltransferase (DGAT)1 are highly expressed in the intestine. Their physiological functions have been examined in the context of whole organisms using genetically engineered mice and, in the case of DGAT1, specific inhibitors. An emerging theme from recent findings is that limiting the rate of TAG synthesis in the intestine can modulate gut hormone secretion, lipid metabolism, and systemic energy balance. The underlying mechanisms and their implications for humans are yet to be explored. Pharmacological inhibition of TAG hydrolysis in the intestinal lumen has been employed to combat obesity and associated disorders with modest efficacy and unwanted side effects. The therapeutic potential of inhibiting specific enzymes involved in intestinal TAG synthesis warrants further investigation. PMID:25231105

  6. Intestinal triacylglycerol synthesis in fat absorption and systemic energy metabolism.

    PubMed

    Yen, Chi-Liang Eric; Nelson, David W; Yen, Mei-I

    2015-03-01

    The intestine plays a prominent role in the biosynthesis of triacylglycerol (triglyceride; TAG). Digested dietary TAG is repackaged in the intestine to form the hydrophobic core of chylomicrons, which deliver metabolic fuels, essential fatty acids, and other lipid-soluble nutrients to the peripheral tissues. By controlling the flux of dietary fat into the circulation, intestinal TAG synthesis can greatly impact systemic metabolism. Genes encoding many of the enzymes involved in TAG synthesis have been identified. Among TAG synthesis enzymes, acyl-CoA:monoacylglycerol acyltransferase 2 and acyl-CoA:diacylglycerol acyltransferase (DGAT)1 are highly expressed in the intestine. Their physiological functions have been examined in the context of whole organisms using genetically engineered mice and, in the case of DGAT1, specific inhibitors. An emerging theme from recent findings is that limiting the rate of TAG synthesis in the intestine can modulate gut hormone secretion, lipid metabolism, and systemic energy balance. The underlying mechanisms and their implications for humans are yet to be explored. Pharmacological inhibition of TAG hydrolysis in the intestinal lumen has been employed to combat obesity and associated disorders with modest efficacy and unwanted side effects. The therapeutic potential of inhibiting specific enzymes involved in intestinal TAG synthesis warrants further investigation.

  7. The Hubble Space Telescope Quasar Absorption Line Key Project: The Unusual Absorption-Line System in the Spectrum of PG 2302+029--Ejected or Intervening?

    NASA Technical Reports Server (NTRS)

    Jannuzi, B. T.; Hartig, G. F.; Kirhakos, S.; Sargent, W. L. W.; Turnshek, D. A.; Weymann, R. J.; Bahcall, J. N.; Bergeron, J.; Boksenberg, A.; Savage, B. D.; Schneider, D. P.; Wolfe, A. M.

    1996-01-01

    We report the discovery of a high-ionization broad absorption line system at a redshift of z(sub abs) = 0.695 in the spectrum of the z(sub em) = 1.052 radio-quiet quasar PG 2302+029. Broad absorption with FWHM from 3000 to 5000 km/s is detected from C iv, N v, and O vi in Hubble Space Telescope (HST) Faint Object Spectrograph spectra of the quasar. A narrow-line system (FWHM approx. 250 km/s) at z(sub abs) = 0.7016 is resolved from the broad blend and includes absorption by Ly alpha and the C iv, N v, and O vi doublets. No absorption by low-ionization metal species (e.g., Si II and Mg II) is detected in the HST or ground-based spectra for either the broad or the narrow system. The centroids of the broad system lines are displaced by approx. 56,000 km/s to the blue of the quasar's broad emission lines. The reddest extent of the broad-line absorption is more than 50,000 km/s from the quasar. The properties of this system are unprecedented, whether it is an intervening or an ejected system.

  8. Coherent perfect absorption in an electromagnetically induced transparency-like (EIT-like) system

    NASA Astrophysics Data System (ADS)

    Zhu, Lei; Guo, Jing; Dong, Liang; Meng, Fan-Yi; Wu, Qun

    2016-09-01

    We propose a scheme for realizing the coherent perfect absorption (CPA) by exploiting the moderate coupling between the electric and magnetic resonators in an electromagnetically induced transparency-like (EIT-like) system. Moreover, the ideal parity-time (PT) symmetry can be established in such a passive system by precisely engineering the rate between the scattering and dissipative losses of resonators as well as their coupling. Specifically, by controlling the phase difference between two incident waves, the absorption ratio of CPA at the peak frequency can be dynamically modulated from 1 to 0. Such a scheme provides an effective route to construct absorbing devices.

  9. Magellan LDSS3 emission confirmation of galaxies hosting metal-rich Lyman α absorption systems

    NASA Astrophysics Data System (ADS)

    Straka, Lorrie A.; Johnson, Sean; York, Donald G.; Bowen, David V.; Florian, Michael; Kulkarni, Varsha P.; Lundgren, Britt; Péroux, Celine

    2016-06-01

    Using the Low Dispersion Survey Spectrograph 3 at the Magellan II Clay Telescope, we target candidate absorption host galaxies detected in deep optical imaging (reaching limiting apparent magnitudes of 23.0-26.5 in g, r, i, and z filters) in the fields of three QSOs, each of which shows the presence of high metallicity, high N_{H I} absorption systems in their spectra (Q0826-2230: zabs = 0.9110, Q1323-0021: zabs = 0.7160, Q1436-0051: zabs = 0.7377, 0.9281). We confirm three host galaxies at redshifts 0.7387, 0.7401, and 0.9286 for two of the Lyman α absorption systems (one with two galaxies interacting). For these systems, we are able to determine the star formation rates (SFRs); impact parameters (from previous imaging detections); the velocity shift between the absorption and emission redshifts; and, for one system, also the emission metallicity. Based on previous photometry, we find these galaxies have L > L*. The [O II] SFRs for these galaxies are in the range 11-25 M⊙ yr-1 (uncorrected for dust), while the impact parameters lie in the range 35-54 kpc. Despite the fact that we have confirmed galaxies at 50 kpc from the QSO, no gradient in metallicity is indicated between the absorption metallicity along the QSO line of sight and the emission line metallicity in the galaxies. We confirm the anticorrelation between impact parameter and N_{H I} from the literature. We also report the emission redshift of five other galaxies: three at zem > zQSO, and two (L < L*) at zem < zQSO not corresponding to any known absorption systems.

  10. Electronic absorption spectra of cryogenic systems with hydrogen bonds

    NASA Astrophysics Data System (ADS)

    Meister, T. G.; Zelikina, G. Ya.; Artamonova, O. M.

    1989-05-01

    The thermodynamic equilibrium ? has been studied by recording the 1Lb band of benzene and toluene (YR 2) dissolved in liquid Kr and CF 4 (toluene was also dissolved in liquid Ar), with addition of CHF 3(R 1XH) in a broad temperature range for each of the systems. The narrowness of the vibronic components (VC) of the 1Lb band in cryogenic solvents, i.e. liquified gases, made it possible to work with the separate vibronic components 6 10( A00) for benzene and 0-0 for toluene. The values of the equilibrium constant K were obtained by measuring the integrated intensities of the VCs of the 1Lb band of the complex and of the monomer. The enthalpy Wg  |Δ Hg| of the unexcited complex R 1XH⋯YR 2 formation was obtained from the temperature dependence of the K values; the enthalpy change Δ W due to the electronic excitation in YR 2 was obtained from the spectral shift due to the H-bond formation; therefore the enthalpy We  |Δ He| of formation of the excited complex R 1XH⋯(YE) 2* was calculated: We = Wg - Δ W. For both complexes in all the solvents used the following enthalpy values were obtained: Wg = 2.4±0.4 kcal mol -1; We = 1.6±0.5 kcal mol -1.

  11. LiCl Dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery

    DOEpatents

    Ko, Suk M.

    1980-01-01

    This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system.

  12. Continuous hyperspectral absorption measurements of colored dissolved organic material in aquatic systems

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, Gary J.; Orrico, Cristina; Moline, Mark A.; Oliver, Matthew; Schofield, Oscar M.

    2003-11-01

    The majority of organic carbon in the oceans is present as dissolved organic matter (DOM) therefore understanding the distribution and dynamics of DOM is central to understanding global carbon cycles. Describing the time-space variability in colored dissolved organic matter (CDOM) has been difficult, as standard spectrophotometric methods for CDOM determination are laborious and susceptible to methodological biases. Previously, measurements of CDOM absorption in discrete water samples by use of a liquid-waveguide capillary cell (LWCC) compared favorably with measurements made with a benchtop spectrophotometer. Given this, we focused on automating the LWCC technique to improve our spatial and temporal sampling capabilities for CDOM. We found strong correlations between CDOM absorption spectra collected from discrete water samples using standard methods and selected corresponding CDOM spectra collected by the automated LWCC system. The near-continuous measurements by the LWCC system made it possible to map the temporal, spatial, and spectral variability of CDOM absorption along the ship track.

  13. Real-time atmospheric absorption spectra for in-flight tuning of an airborne dial system

    NASA Technical Reports Server (NTRS)

    Dombrowski, M.; Walden, H.; Schwemmer, G. K.; Milrod, J.; Korb, C. L.

    1986-01-01

    Real-time measurements of atmospheric absorption spectra are displayed and used to precisely calibrate and fix the frequency of an Alexandrite laser to specific oxygen absorption features for airborne Differential Absorption Lidar (DIAL) measurements of atmospheric pressure and temperature. The DIAL system used contains two narrowband tunable Alexandrite lasers: one is electronically scanned to tune to oxygen absorption features for on-line signals while the second is used to obtain off-line (nonabsorbed) atmospheric return signals. The lidar operator may select the number of shots to be averaged, the altitude, and altitude interval over which the signals are averaged using single key stroke commands. The operator also determines exactly which oxygen absorption lines are scanned by comparing the line spacings and relative strengths with known line parameters, thus calibrating the laser wavelength readout. The system was used successfully to measure the atmospheric pressure profile on the first flights of this lidar, November 20, and December 9, 1985, aboard the NASA Wallops Electra aircraft.

  14. Airborne differential absorption lidar system for measurements of atmospheric water vapor and aerosols

    NASA Technical Reports Server (NTRS)

    Carter, Arlen F.; Allen, Robert J.; Mayo, M. Neale; Butler, Carolyn F.; Grossman, Benoist E.; Ismail, Syed; Grant, William B.; Browell, Edward V.; Higdon, Noah S.; Mayor, Shane D.; Ponsardin, Patrick; Hueser, Alene W.

    1994-01-01

    An airborne differential absorption lidar (DIAL) system has been developed at the NASA Langley Research Center for remote measurements of atmospheric water vapor (H2O) and aerosols. A solid-state alexandrite laser with a 1-pm linewidth and greater than 99.85% spectral purity was used as the on-line transmitter. Solid-state avalanche photodiode detector technology has replaced photomultiplier tubes in the receiver system, providing an average increase by a factor of 1.5-2.5 in the signal-to-noise ratio of the H2O measurement. By incorporating advanced diagnostic and data-acquisition instrumentation into other subsystems, we achieved additional improvements in system operational reliability and measurement accuracy. Laboratory spectroscopic measurements of H2O absorption-line parameters were performed to reduce the uncertainties in our knowledge of the absorption cross sections. Line-center H2O absorption cross sections were determined, with errors of 3-6%, for more than 120 lines in the 720-nm region. Flight tests of the system were conducted during 1989-1991 on the NASA Wallops Flight Facility Electra aircraft, and extensive intercomparison measurements were performed with dew-point hygrometers and H2O radiosondes. The H2O distributions measured with the DIAL system differed by less than 10% from the profiles determined with the in situ probes in a variety of atmospheric conditions.

  15. Airborne differential absorption lidar system for measurements of atmospheric water vapor and aerosols.

    PubMed

    Higdon, N S; Browell, E V; Ponsardin, P; Grossmann, B E; Butler, C F; Chyba, T H; Mayo, M N; Allen, R J; Heuser, A W; Grant, W B; Ismail, S; Mayor, S D; Carter, A F

    1994-09-20

    An airborne differential absorption lidar (DIAL) system has been developed at the NASA Langley Research Center for remote measurements of atmospheric water vapor (H(2)O) and aerosols. A solid-state alexandrite laser with a 1-pm linewidth and > 99.85% spectral purity was used as the on-line transmitter. Solid-state avalanche photodiode detector technology has replaced photomultiplier tubes in the receiver system, providing an average increase by a factor of 1.5-2.5 in the signal-to-noise ratio of the H(2)O measurement. By incorporating advanced diagnostic and data-acquisition instrumentation into other subsystems, we achieved additional improvements in system operational reliability and measurement accuracy. Laboratory spectroscopic measurements of H(2)O absorption-line parameters were perfo med to reduce the uncertainties in our knowledge of the absorption cross sections. Line-center H(2)O absorption cross sections were determined, with errors of 3-6%, for more than 120 lines in the 720-nm region. Flight tests of the system were conducted during 1989-1991 on the NASA Wallops Flight Facility Electra aircraft, and extensive intercomparison measurements were performed with dew-point hygrometers and H(2)O radiosondes. The H(2)O distributions measured with the DIAL system differed by ≤ 10% from the profiles determined with the in situ probes in a variety of atmospheric conditions.

  16. Airborne differential absorption lidar system for measurements of atmospheric water vapor and aerosols.

    PubMed

    Higdon, N S; Browell, E V; Ponsardin, P; Grossmann, B E; Butler, C F; Chyba, T H; Mayo, M N; Allen, R J; Heuser, A W; Grant, W B; Ismail, S; Mayor, S D; Carter, A F

    1994-09-20

    An airborne differential absorption lidar (DIAL) system has been developed at the NASA Langley Research Center for remote measurements of atmospheric water vapor (H(2)O) and aerosols. A solid-state alexandrite laser with a 1-pm linewidth and > 99.85% spectral purity was used as the on-line transmitter. Solid-state avalanche photodiode detector technology has replaced photomultiplier tubes in the receiver system, providing an average increase by a factor of 1.5-2.5 in the signal-to-noise ratio of the H(2)O measurement. By incorporating advanced diagnostic and data-acquisition instrumentation into other subsystems, we achieved additional improvements in system operational reliability and measurement accuracy. Laboratory spectroscopic measurements of H(2)O absorption-line parameters were perfo med to reduce the uncertainties in our knowledge of the absorption cross sections. Line-center H(2)O absorption cross sections were determined, with errors of 3-6%, for more than 120 lines in the 720-nm region. Flight tests of the system were conducted during 1989-1991 on the NASA Wallops Flight Facility Electra aircraft, and extensive intercomparison measurements were performed with dew-point hygrometers and H(2)O radiosondes. The H(2)O distributions measured with the DIAL system differed by ≤ 10% from the profiles determined with the in situ probes in a variety of atmospheric conditions. PMID:20941181

  17. A nonlinear screen as an element for sound absorption and frequency conversion systems

    NASA Astrophysics Data System (ADS)

    Rudenko, O. V.

    2016-01-01

    The paper discusses a model for a screen with dissipative and nonlinear elastic properties that can be used in acoustic sound absorption and frequency conversion systems. Calculation and estimation schemes are explained that are necessary for understanding the functional capabilities of the device. Examples of the nonlinear elements in the screen and promising applications are described.

  18. Portable Instrument to Measure CDOM Light Absorption in Aquatic Systems: WPI Success Story

    NASA Technical Reports Server (NTRS)

    2001-01-01

    World Precision Instruments, Inc. (WPI), of Sarasota, FL, in collaboration with NASA's John C. Stennis Space Center, has developed an innovative instrument to accurately measure Colored Dissolved Organic Matter (CDOM) absorption in the field. This successful collaboration has culminated in an exciting new device, called the UltraPath, now commercially available through WPI. Traditional methods of measuring absorption of dissolved materials require special handling and storage prior to measurement. Use of laboratory spectrophotometers as the measuring devices have proven time consuming, cumbersome, and delicate to handle. The UltraPath provides a low-cost, highly sensitive, rugged, portable system that is capable of high sensitivity measurements in widely divergent waters.

  19. Coherent manipulation of absorption by intense fields in four level ladder system

    NASA Astrophysics Data System (ADS)

    Kumar, Pardeep; Dasgupta, Shubhrangshu

    2016-05-01

    Nonlinear optical processes attributed to the dependence of the susceptibility of the medium on the input fluence can be remarkably manipulated by the quantum interference and coherence. One of these processes, the optical bistability (OB), that refers to the possibilities of two stable outputs for the same input fields, can also be modified by quantum coherence. Further, the nonlinear dependence of the absorption on the power of the input light gives rise to interesting processes like saturable absorption (SA) and reverse saturable absorption (RSA). While the SA corresponds to the decrease in the absorption coefficient with the increase of intensity of input light, the RSA corresponds to otherwise, that finds applications in optical limiting. We show, using a four-level Ladder system, how a control field manipulates these processes for an intense probe field applied in the excited state transition. The nonlinear absorption increases whereas the threshold of OB decreases in presence of a control field. We further delineates how the control field and the decay rates modifies SA and RSA. The control of these processes find applications in optical switching, optical limiting and optical communications.

  20. Separation of scattering and absorption contributions in UV/visible spectra of resonant systems.

    PubMed

    Micali, N; Mallamace, F; Castriciano, M; Romeo, A; Scolaro, L M

    2001-10-15

    Resonance light scattering (RLS) is a phenomenon due to an enhancement of the scattered light in close proximity to an absorption band. The effect is easily detectable in the case of strongly absorbing chromophores, which are able to interact, thus leading to large aggregates (Pasternack, R. F.; Collings, P. J. Science 1995, 269, 935). The measurement of absorption spectra from solutions containing such resonant systems can lead to misleading results. In this paper, a simple method is described to obtain absorption spectra of aggregated species with a fairly good correction of the scattering component. The RLS spectrum, obtained using a common spectrofluorimeter, is correlated to the extinction spectrum of the same sample, allowing for an estimation of the scattering contribution to the total extinction spectrum. The method has been successfully applied both on real samples containing aggregated chromophores, such as porphyrins, chlorophyll a and gold colloids, and by simulating extinction spectra.

  1. Analytical and experimental evaluation of solar absorption and vapor compression residential cooling systems

    SciTech Connect

    Darkazalli, G.; Lawley, T.J.

    1981-01-01

    Results from the University of Texas at Arlington/Solar Energy Research Facility (UTA/SERF) analytical and experimental study on residential solar heating and cooling systems are given. A description of the 145 m/sup 2/ solar residence, its basic components, operation, and controls of various combinations of system components is presented. A comparison of solar powered absorption cooling and solar assisted electric powered heat pump cooling for a single family residence is also presented. 2 refs.

  2. Dust depletion of Ca and Ti in QSO absorption-line systems

    NASA Astrophysics Data System (ADS)

    Guber, C. R.; Richter, P.

    2016-06-01

    Aims: To explore the role of titanium- and calcium-dust depletion in gas in and around galaxies, we systematically study Ti/Ca abundance ratios in intervening absorption-line systems at low and high redshift. Methods: We investigate high-resolution optical spectra obtained by the UVES instrument at the Very Large Telescope (VLT) and spectroscopically analyze 34 absorption-line systems at z ≤ 0.5 to measure column densities (or limits) for Ca ii and Ti ii. We complement our UVES data set with previously published absorption-line data on Ti/Ca for redshifts up to z ~ 3.8. Our absorber sample contains 110 absorbers including damped Lyman α systems (DLAs), sub-DLAs, and Lyman-Limit systems (LLS). We compare our Ti/Ca findings with results from the Milky Way and the Magellanic Clouds and discuss the properties of Ti/Ca absorbers in the general context of quasar absorption-line systems. Results: Our analysis indicates that there are two distinct populations of absorbers with either high or low Ti/Ca ratios with a separation at [Ti/Ca] ≈ 1. While the calcium-dust depletion in most of the absorbers appears to be severe, the titanium depletions are mild in systems with high Ti/Ca ratios. The derived trend indicates that absorbers with high Ti/Ca ratios have dust-to-gas ratios that are substantially lower than in the Milky Way. We characterize the overall nature of the absorbers by correlating Ti/Ca with other observables (e.g., metallicity, velocity-component structure) and by modeling the ionization properties of singly-ionized Ca and Ti in different environments. Conclusions: We conclude that Ca ii and Ti ii bearing absorption-line systems trace predominantly neutral gas in the disks and inner halo regions of galaxies, where the abundance of Ca and Ti reflects the local metal and dust content of the gas. Our study suggests that the Ti/Ca ratio represents a useful measure for the gas-to-dust ratio and overall metallicity in intervening absorption-line systems.

  3. 20. INTERIOR, COAL CHUTES (G.S.A. PHOTOCOPY, N.D.) (4 x 5 ...

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

    20. INTERIOR, COAL CHUTES (G.S.A. PHOTOCOPY, N.D.) (4 x 5 NEGATIVE) - U.S. General Services Administration, Central Heating Plant, C & D Streets between Twelfth & Thirteenth Streets Southwest, Washington, District of Columbia, DC

  4. 19. INTERIOR, 'CHILLER NO. 2' (G.S.A. PHOTOCOPY, N.D.) (4 x ...

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

    19. INTERIOR, 'CHILLER NO. 2' (G.S.A. PHOTOCOPY, N.D.) (4 x 5 NEGATIVE) - U.S. General Services Administration, Central Heating Plant, C & D Streets between Twelfth & Thirteenth Streets Southwest, Washington, District of Columbia, DC

  5. 18. INTERIOR, CATWALK AND PIPES (G.S.A. PHOTOCOPY, N.D.) (4 x ...

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

    18. INTERIOR, CATWALK AND PIPES (G.S.A. PHOTOCOPY, N.D.) (4 x 5 NEGATIVE) - U.S. General Services Administration, Central Heating Plant, C & D Streets between Twelfth & Thirteenth Streets Southwest, Washington, District of Columbia, DC

  6. 77 FR 5020 - General Services Administration Acquisition Regulation; Information Collection; GSA Form 527...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-01

    ... ADMINISTRATION General Services Administration Acquisition Regulation; Information Collection; GSA Form 527... and Financial Information'' on your attached document. Fax: (202) 501-4067. Mail: General Services... provided. SUPPLEMENTARY INFORMATION: A. Purpose The General Services Administration will be requesting...

  7. 77 FR 31016 - General Services Administration Acquisition Regulation; Submission for OMB Review; GSA Mentor...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-24

    ... Manual (GSAM). A notice was published in the Federal Register at 77 FR 9659, on February 17, 2012. No... First Street NE., Washington, DC 20417. ATTN: Hada Flowers/IC 3090-0286, GSA Mentor-Prot g...

  8. 41 CFR 102-117.350 - How will GSA use reports I submit?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... transportation related services will provide GSA with: (1) The ability to assess the magnitude and key... addition, this information will assist you in showing your management the magnitude of your...

  9. 41 CFR 102-117.350 - How will GSA use reports I submit?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... transportation related services will provide GSA with: (1) The ability to assess the magnitude and key... addition, this information will assist you in showing your management the magnitude of your...

  10. 41 CFR 102-117.350 - How will GSA use reports I submit?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... transportation related services will provide GSA with: (1) The ability to assess the magnitude and key... addition, this information will assist you in showing your management the magnitude of your...

  11. Solar Absorption Refrigeration System for Air-Conditioning of a Classroom Building in Northern India

    NASA Astrophysics Data System (ADS)

    Agrawal, Tanmay; Varun; Kumar, Anoop

    2015-10-01

    Air-conditioning is a basic tool to provide human thermal comfort in a building space. The primary aim of the present work is to design an air-conditioning system based on vapour absorption cycle that utilizes a renewable energy source for its operation. The building under consideration is a classroom of dimensions 18.5 m × 13 m × 4.5 m located in Hamirpur district of Himachal Pradesh in India. For this purpose, cooling load of the building was calculated first by using cooling load temperature difference method to estimate cooling capacity of the air-conditioning system. Coefficient of performance of the refrigeration system was computed for various values of strong and weak solution concentration. In this work, a solar collector is also designed to provide required amount of heat energy by the absorption system. This heat energy is taken from solar energy which makes this system eco-friendly and sustainable. A computer program was written in MATLAB to calculate the design parameters. Results were obtained for various values of solution concentrations throughout the year. Cost analysis has also been carried out to compare absorption refrigeration system with conventional vapour compression cycle based air-conditioners.

  12. Systems having optical absorption layer for mid and long wave infrared and methods for making the same

    DOEpatents

    Kuzmenko, Paul J

    2013-10-01

    An optical system according to one embodiment includes a substrate; and an optical absorption layer coupled to the substrate, wherein the optical absorption layer comprises a layer of diamond-like carbon, wherein the optical absorption layer absorbs at least 50% of mid wave infrared light (3-5 .mu.m wavelength) and at least 50% of long wave infrared light (8-13 .mu.m wavelength). A method for applying an optical absorption layer to an optical system according to another embodiment includes depositing a layer of diamond-like carbon of an optical absorption layer above a substrate using plasma enhanced chemical vapor deposition, wherein the optical absorption layer absorbs at least 50% of mid wave infrared light (3-5 .mu.m wavelength) and at least 50% of long wave infrared light (8-13 .mu.m wavelength). Additional systems and methods are also presented.

  13. Origins of Absorption Systems of Classical Nova V2659 Cyg (Nova Cyg 2014)

    NASA Astrophysics Data System (ADS)

    Arai, A.; Kawakita, H.; Shinnaka, Y.; Tajitsu, A.

    2016-10-01

    We report on high-dispersion spectroscopy results of a classical nova V2659 Cyg (Nova Cyg 2014) that are taken 33.05 days after the V-band maximum. The spectrum shows two distinct blueshifted absorption systems originating from H i, Fe ii, Ca ii, etc. The radial velocities of the absorption systems are ‑620 km s‑1, and ‑1100 to ‑1500 km s‑1. The higher velocity component corresponds to the P-Cygni absorption features frequently observed in low-resolution spectra. Much larger numbers of absorption lines are identified at the lower velocity. These mainly originate from neutral or singly ionized Fe-peak elements (Fe i, Ti ii, Cr ii, etc.). Based on the results of our spectroscopic observations, we discuss the structure of the ejecta of V2659 Cyg. We conclude that the low- and high-velocity components are likely to be produced by the outflow wind and the ballistic nova ejecta, respectively.

  14. Field demonstration of the combined effects of absorption and evapotranspiration on septic system drainfield capacity.

    PubMed

    Rainwater, Ken; Jackson, Andrew; Ingram, Wesley; Lee, Chang Yong; Thompson, David; Mollhagen, Tony; Ramsey, Heyward; Urban, Lloyd

    2005-01-01

    Drainfields for disposal of septic tank effluents are typically designed by considering the loss of water by either upward evapotranspiration into the atmosphere or lateral and downward absorption into the adjacent soil. While this approach is appropriate for evapotranspiration systems, absorption systems allow water loss by both mechanisms. It was proposed that, in areas where high evapotranspiration rates coincide with permeable soils, drainfield sizes could be substantially reduced by accounting for both mechanisms. A two-year field demonstration was conducted to determine appropriate design criteria for areas typical of the Texas High Plains. The study consisted of evaluating the long-term acceptance rates for three different drainfield configurations: evapotranspiration only, absorption only, and combined conditions. A second field demonstration repeated the experiments for additional observation of the combined evapotranspiration and absorption and achieved similar results as the first study. The field tests indicated that the current design loading criteria may be increased by at least a factor of two for the Texas High Plains region and other Texas areas with similar soil composition and evapotranspiration rates, while still retaining a factor of safety of two.

  15. Spectral control of an alexandrite laser for an airborne water-vapor differential absorption lidar system

    NASA Technical Reports Server (NTRS)

    Ponsardin, Patrick; Grossmann, Benoist E.; Browell, Edward V.

    1994-01-01

    A narrow-linewidth pulsed alexandrite laser has been greatly modified for improved spectral stability in an aircraft environment, and its operation has been evaluated in the laboratory for making water-vapor differential absorption lidar measurements. An alignment technique is described to achieve the optimum free spectral range ratio for the two etalons inserted in the alexandrite laser cavity, and the sensitivity of this ratio is analyzed. This technique drastically decreases the occurrence of mode hopping, which is commonly observed in a tunable, two-intracavity-etalon laser system. High spectral purity (greater than 99.85%) at 730 nm is demonstrated by the use of a water-vapor absorption line as a notch filter. The effective cross sections of 760-nm oxygen and 730-nm water-vapor absorption lines are measured at different pressures by using this laser, which has a finite linewidth of 0.02 cm(exp -1) (FWHM). It is found that for water-vapor absorption linewidths greater than 0.04 cm(exp -1) (HWHM), or for altitudes below 10 km, the laser line can be considered monochromatic because the measured effective absorption cross section is within 1% of the calculated monochromatic cross section. An analysis of the environmental sensitivity of the two intracavity etalons is presented, and a closed-loop computer control for active stabilization of the two intracavity etalons in the alexandrite laser is described. Using a water-vapor absorption line as a wavelength reference, we measure a long-term frequency drift (approximately 1.5 h) of less than 0.7 pm in the laboratory.

  16. Assessment of absorption potential of poorly water-soluble drugs by using the dissolution/permeation system.

    PubMed

    Kataoka, Makoto; Yano, Koji; Hamatsu, Yoriko; Masaoka, Yoshie; Sakuma, Shinji; Yamashita, Shinji

    2013-11-01

    This study aims to assess the absorption potential of oral absorption of poorly water-soluble drugs by using the dissolution/permeation system (D/P system). The D/P system can be used to perform analysis of drug permeation under dissolution process and can predict the fraction of absorbed dose in humans. When celecoxib at 1/100 of a clinical dose was applied to the D/P system, percentage of dose dissolved and permeated significantly decreased with an increase in the applied amount, resulting in the oral absorption being predicted to be 22-55%. Whereas similar dissolution and permeation profiles of montelukast sodium were observed, estimated absorption (69-85%) was slightly affected. Zafirlukast absorption (33-36%) was not significantly affected by the dose, although zafirlukast did not show complete dissolution. The relationship between clinical dose and predicted oral absorption of drugs corresponded well to clinical observations. The limiting step of the oral absorption of celecoxib and montelukast sodium was solubility, while that of zafirlukast was dissolution rate. However, due to high permeability of montelukast, oral absorption was not affected by dose. Therefore, the D/P system is a useful tool to assess the absorption potential of poorly water-soluble drugs for oral use.

  17. Assessment of absorption potential of poorly water-soluble drugs by using the dissolution/permeation system.

    PubMed

    Kataoka, Makoto; Yano, Koji; Hamatsu, Yoriko; Masaoka, Yoshie; Sakuma, Shinji; Yamashita, Shinji

    2013-11-01

    This study aims to assess the absorption potential of oral absorption of poorly water-soluble drugs by using the dissolution/permeation system (D/P system). The D/P system can be used to perform analysis of drug permeation under dissolution process and can predict the fraction of absorbed dose in humans. When celecoxib at 1/100 of a clinical dose was applied to the D/P system, percentage of dose dissolved and permeated significantly decreased with an increase in the applied amount, resulting in the oral absorption being predicted to be 22-55%. Whereas similar dissolution and permeation profiles of montelukast sodium were observed, estimated absorption (69-85%) was slightly affected. Zafirlukast absorption (33-36%) was not significantly affected by the dose, although zafirlukast did not show complete dissolution. The relationship between clinical dose and predicted oral absorption of drugs corresponded well to clinical observations. The limiting step of the oral absorption of celecoxib and montelukast sodium was solubility, while that of zafirlukast was dissolution rate. However, due to high permeability of montelukast, oral absorption was not affected by dose. Therefore, the D/P system is a useful tool to assess the absorption potential of poorly water-soluble drugs for oral use. PMID:23811221

  18. [Signal analysis and spectrum distortion correction for tunable diode laser absorption spectroscopy system].

    PubMed

    Bao, Wei-Yi; Zhu, Yong; Chen, Jun; Chen, Jun-Qing; Liang, Bo

    2011-04-01

    In the present paper, the signal of a tunable diode laser absorption spectroscopy (TDLAS) trace gas sensing system, which has a wavelength modulation with a wide range of modulation amplitudes, is studied based on Fourier analysis method. Theory explanation of spectrum distortion induced by laser intensity amplitude modulation is given. In order to rectify the spectrum distortion, a method of synchronous amplitude modulation suppression by a variable optical attenuator is proposed. To validate the method, an experimental setup is designed. Absorption spectrum measurement experiments on CO2 gas were carried out. The results show that the residual laser intensity modulation amplitude of the experimental system is reduced to -0.1% of its original value and the spectrum distortion improvement is 92% with the synchronous amplitude modulation suppression. The modulation amplitude of laser intensity can be effectively reduced and the spectrum distortion can be well corrected by using the given correction method and system. By using a variable optical attenuator in the TDLAS (tunable diode laser absorption spectroscopy) system, the dynamic range requirements of photoelectric detector, digital to analog converter, filters and other aspects of the TDLAS system are reduced. This spectrum distortion correction method can be used for online trace gas analyzing in process industry.

  19. Average Extinction Curves and Abundances at 1Absorption Systems

    NASA Astrophysics Data System (ADS)

    Vanden Berk, D. E.; York, D. G.; Khare, P.; Kulkarni, V. P.; Crotts, A. P. S.; Lauroesch, J. T.; Richards, G. T.; Yip, C.-W.; Schneider, D. P.; Welty, D.; Alsayyad, Y.; Shanidze, N.; Vanlandingham, J.; Tumlinson, J.; Kumar, A.; Lundgren, B.; Baugher, B.; Hall, P. B.; Jenkins, E. B.; Menard, B.; Rao, S.; Turnshek, D.; Brinkman, J.; SDSS Collaboration

    2005-12-01

    We present average extinction curves and relative abundance measurements for a sample of 809 MgII absorption line systems, with 1.0 < zabs < 1.86, identified in the spectra of SDSS quasars. Extinction curves for numerous sub-samples were generated by comparing geometric mean absorber-frame spectra with those of matching quasar spectra without absorbers. There is clear evidence for the presence of dust in the intervening systems. All of the extinction curves are similar to the SMC extinction curve, and the 2175{Å} absorption feature is not detectable in the curves of any of the sub-samples. Quasars with absorbers are at least three times as likely to have highly reddened spectra, compared to quasars without detected absorption systems. The average absorber-frame color excess, E(B-V), ranges from <0.001 to 0.085, and depends on the properties of the absorbers in the sub-samples. The column densities of numerous first ions do not show as correspondingly large a variation as the color excess. The depletion pattern in the high E(B-V) samples is similar to that of Galactic halo clouds, and is consistent with those found for individual damped Ly α systems. Funding for the Sloan Digital Sky Survey (SDSS) has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Aeronautics and Space Administration, the National Science Foundation, the U.S. Department of Energy, the Japanese Monbukagakusho, the Max Planck Society, and the HEFCE.

  20. The flow of baryons: the origin of metal absorption systems at z > 3

    NASA Astrophysics Data System (ADS)

    Díaz, C. G.; Ryan-Weber, E. V.; Cooke, J. D.; Crighton, N. H.; Díaz, R. J.

    2016-08-01

    The chemical enrichment of the Universe refers to the cosmic build-up of chemical elements produced by stars (metals) that disperse them to the interstellar medium during their life and dead. The enriched material can reach intergalactic distances helped by galactic-scale winds and, eventually, can flow back to a galaxy. These metals are crucial ingredients for star formation because they provide a cooling mechanism for the gas. Therefore, understanding the flow of baryons to and from galaxies is fundamental for galaxy formation and evolution. Our work aims at testing the origin of metal absorption systems in the spectra of background quasars, by studying the environment of these absorption systems and the galaxies that produce them. In particular, we search for galaxies near triply-ionized carbon (Civ) systems at redshift . In this contribution, we present recent results that suggest that the mechanisms of dispersal of metals could have been more efficient at than at . We discuss the limitations of the result and present the current status of our search for the origin of Civ absorption systems.

  1. Energy cost of riding bicycles with shock absorption systems on a flat surface.

    PubMed

    Nielens, H; Lejeune, T M

    2001-08-01

    Bike shock absorption systems reduce the energy variation induced by terrain irregularities, leading to a greater comfort. However, they may also induce an increase in energy expenditure for the rider. More specifically, cross-country racers claim that rear shock absorption systems generate significant energy loss. The energy losses caused by such systems may be divided in terrain-induced or rider-induced. This study aims at evaluating the rider-induced energy loss of modern suspended bicycles riding on a flat surface. Twelve experienced competitive racers underwent three multistage gradational tests (50 to 250 W) on a cross-country bicycle mounted on an electromagnetically braked cycle ergometer. Three different tests were performed on a fully suspended bike, front suspended and non-suspended bicycle, respectively. The suspension mode has no significant effect on VO2. The relative difference of VO2 between the front-suspended or full-suspended bike and the rigid bike reaches a non significant maximum of only 3%. The claims of many competitors who still prefer front shock absorption systems could be related to a possible significant energy loss that could be present at powers superior to 250 W or when they stand on the pedals. It could also be generated by terrain-induced energy loss.

  2. Determining CDOM Absorption Spectra in Diverse Aquatic Environments Using a Multiple Pathlength, Liquid Core Waveguide System

    NASA Technical Reports Server (NTRS)

    Miller, Richard L.; Belz, Mathias; DelCastillo, Carlos; Trzaska, Rick

    2001-01-01

    We evaluated the accuracy, sensitivity and precision of a multiple pathlength, liquid core waveguide (MPLCW) system for measuring colored dissolved organic matter (CDOM) absorption in the UV-visible spectral range (370-700 nm). The MPLCW has four optical paths (2.0, 9.8, 49.3, and 204 cm) coupled to a single Teflon AF sample cell. Water samples were obtained from inland, coastal and ocean waters ranging in salinity from 0 to 36 PSU. Reference solutions for the MPLCW were made having a refractive index of the sample. CDOM absorption coefficients, aCDOM, and the slope of the log-linearized absorption spectra, S, were compared with values obtained using a dual-beam spectrophotometer. Absorption of phenol red secondary standards measured by the MPLCW at 558 nm were highly correlated with spectrophotometer values and showed a linear response across all four pathlengths. Values of aCDOM measured using the MPLCW were virtually identical to spectrophotometer values over a wide range of concentrations. The dynamic range of aCDOM for MPLCW measurements was 0.002 - 231.5 m-1. At low CDOM concentrations spectrophotometric aCDOM were slightly greater than MPLCW values and showed larger fluctuations at longer wavelengths due to limitations in instrument precision. In contrast, MPLCW spectra followed an exponential to 600 nm for all samples.

  3. Use of absorption refrigerating machines in mine air-conditioning systems

    SciTech Connect

    Duganov, G.V.; Rozhko, V.F.; Shtompel, A.I.; Timofeevskii, L.S.

    1984-07-01

    This article describes lithium bromide absorption refrigerating machines (LBARMs) designed for use in mine air-conditioning systems (MACS). The application of LBARMs in MACS is difficult due to the elevation of temperature of the cold carrier when supplied to the mine air refrigerants. A thermodynamic and thermoeconomic analysis was conducted to determine the principal lines of LBARM design for creating a suitable microclimate in underground mines. The MACS will maintain the temperature in the mines at a horizon of 913 m at 24-26/sup 0/C. A scheme is proposed for stage-by-stage cooling by connecting two machines in succession. It is concluded that the use of absorption refrigerating machines in coal mine air-conditioning systems facilitates the integrated and economic use of heat energy as well as of secondary heat resources for cold generation.

  4. Cascade Reverse Osmosis Air Conditioning System: Cascade Reverse Osmosis and the Absorption Osmosis Cycle

    SciTech Connect

    2010-09-01

    BEETIT Project: Battelle is developing a new air conditioning system that uses a cascade reverse osmosis (RO)-based absorption cycle. Analyses show that this new cycle can be as much as 60% more efficient than vapor compression, which is used in 90% of air conditioners. Traditional vapor-compression systems use polluting liquids for a cooling effect. Absorption cycles use benign refrigerants such as water, which is absorbed in a salt solution and pumped as liquid—replacing compression of vapor. The refrigerant is subsequently separated from absorbing salt using heat for re-use in the cooling cycle. Battelle is replacing thermal separation of refrigerant with a more efficient reverse osmosis process. Research has shown that the cycle is possible, but further investment will be needed to reduce the number of cascade reverse osmosis stages and therefore cost.

  5. Conversion between electromagnetically induced absorption and transparency in a four-level system

    NASA Astrophysics Data System (ADS)

    Sarkisyan, D.; Sargsyan, A.; Wilson-Gordon, A. D.; Cartaleva, S.

    2015-01-01

    A narrowband R-type resonance is formed in a Λ-system, on the D1 line of Rb atomic vapor using two continuous diode lasers with λ=795 nm. A 8mm- long cell filled with the Rb vapor and 20 Torr neon gas has been used. We have shown that use of an additional (3rd) laser which is resonant with the Rb D2 line (λ=780 nm) makes it possible to control the amplitude and sign of the R -type resonance, i.e. to convert a resonance which demonstrates increase in absorption into one which demonstrates reduction in absorption. The good signal/noise ratio of the observed resonance allows us to follow its behavior in an applied magnetic field from several gauss to several hundred gauss. A description in terms of double-Λ systems allows us to explain the experimental results in a simple manner.

  6. Observing Superexcited State Dynamics in Atomic and Molecular Systems by Attosecond Transient Absorption

    NASA Astrophysics Data System (ADS)

    Liao, Chen-Ting; Li, Xuan; Haxton, Daniel; Lucchese, Robert; McCurdy, C. William; Sandhu, Arvinder

    2016-05-01

    The electron dynamics of superexcited atomic and molecular states are studied experimentally and theoretically. For atomic systems, such as 3 s 3p6 5 p autoionizing state in argon, delay-dependent optical density (OD) only shows positive changes. However, molecular system such as Oxygen shows positive OD in the case of nsσg and nsπg autoionizing states of oxygen and negative OD for ndσg states. The negative OD change corresponds to the reduced absorption comparing to the static continuum background. We investigated this electron symmetry dependent effect in depth experimentally by attosecond transient absorption spectroscopy, and theoretically by multiconfiguration time-dependent Hartree-Fock (MCTDHF) method.

  7. Development of Cellular Absorptive Tracers (CATs) for a Quantitative Characterization of Microbial Mass in Flow Systems

    SciTech Connect

    Saripalli, Prasad; Brown, Christopher F.; Lindberg, Michael J.

    2005-03-16

    We report on a new Cellular Absorptive Tracers (CATs) method, for a simple, non-destructive characterization of bacterial mass in flow systems. Results show that adsorption of a CAT molecule into the cellular mass results in its retardation during flow, which is a good, quantitative measure of the biomass quantity and distribution. No such methods are currently available for a quantitative characterization of cell mass.

  8. The capability of fluoroscopic systems to determine differential Roentgen-ray absorption

    NASA Technical Reports Server (NTRS)

    Baily, N. A.; Crepeau, R. L.

    1975-01-01

    A clinical fluoroscopic unit used in conjunction with a TV image digitization system was investigated to determine its capability to evaluate differential absorption between two areas in the same field. Fractional contrasts and minimum detectability for air, several concentrations of Renografin-60, and aluminum were studied using phantoms of various thicknesses. Results showed that the videometric response, when treated as contrast, shows a linear response with absorber thickness up to considerable thicknesses.

  9. Triple-effect absorption refrigeration system with double-condenser coupling

    DOEpatents

    DeVault, Robert C.; Biermann, Wendell J.

    1993-01-01

    A triple effect absorption refrigeration system is provided with a double-condenser coupling and a parallel or series circuit for feeding the refrigerant-containing absorbent solution through the high, medium, and low temperature generators utilized in the triple-effect system. The high temperature condenser receiving vaporous refrigerant from the high temperature generator is double coupled to both the medium temperature generator and the low temperature generator to enhance the internal recovery of heat within the system and thereby increase the thermal efficiency thereof.

  10. Triple-effect absorption refrigeration system with double-condenser coupling

    DOEpatents

    DeVault, R.C.; Biermann, W.J.

    1993-04-27

    A triple effect absorption refrigeration system is provided with a double-condenser coupling and a parallel or series circuit for feeding the refrigerant-containing absorbent solution through the high, medium, and low temperature generators utilized in the triple-effect system. The high temperature condenser receiving vaporous refrigerant from the high temperature generator is double coupled to both the medium temperature generator and the low temperature generator to enhance the internal recovery of heat within the system and thereby increase the thermal efficiency thereof.

  11. Automated system for x-ray absorption spectroscopy of nanoparticle nucleation and growth

    SciTech Connect

    Calvin, S.; Carpenter, E.E.; Cestone, V.; Kurihara, L.K.; Harris, V.G.; Brown, E.C.

    2005-01-01

    X-ray absorption spectroscopy (XAS) is a useful tool for studying nanoparticle synthesis and growth. Described here is a system for automating synthesis and data collection, allowing time-resolved XAS measurements at a synchrotron to be accurately combined with measurements made under identical conditions elsewhere, and promising the ability to use XAS with experiments in combinatorial chemistry. The primary components of this system are a commercial parallel processor and a custom flow cell. The system has been used to collect data on the synthesis of iron oxides from iron(II) acetylacetonate.

  12. Observation of low field microwave absorption in co-doped ZnO system

    NASA Astrophysics Data System (ADS)

    Mahule, Tebogo S.; Srinivasu, Vijaya V.; Das, Jayashree

    2016-10-01

    Room temperature low field microwave absorption (LFMA) in magnetic materials find application in microwave absorbers and low field sensors. However not all the magnetic materials show LFMA and the phenomenon is not fully understood. We report on the observation of low field microwave absorption (LFMA) or the non-resonant microwave absorption (NRMA) in the transition metal (TM) co-doped ZnO samples of the composition Zn1-x(TM:TM)xO synthesized by solid state reaction technique. LFMA peaks and hysteresis matches very well with that of the magnetization hysteresis loop and the anisotropy fields at room temperature similar to the reports in the literature for other magnetic systems. However we show through our careful experiments that such a correlation between LFMA and the magnetization does not survive at low temperatures and particularly at 10 K the LFMA hysteresis collapses in our TM co-doped ZnO system; whereas the magnetization hysteresis loop becomes very big and anisotropy field becomes bigger in the range of kOe. We interpret the LFMA as field dependent surface impedance or eddy current losses, in terms of a possible role of anomalous hall resistivity that follows magnetization and the ordinary hall resistivity that only follows the applied field. We then argue that LFMA accordingly follows magnetization or applied field when AHE or OHE dominates respectively. Also we confirm the absence of LFMA signals in the rare earth co-doped ZnO system.

  13. Enhancement of oral absorption of curcumin by self-microemulsifying drug delivery systems.

    PubMed

    Cui, Jing; Yu, Bo; Zhao, Yu; Zhu, Weiwei; Li, Houli; Lou, Hongxiang; Zhai, Guangxi

    2009-04-17

    Curcumin is a poorly water-soluble drug and its oral bioavailability is very low. A new self-microemulsifying drug delivery system (SMEDDS) has been successfully developed to improve the solubility and oral absorption of curcumin. Suitable compositions of SMEDDS formulation were screened via solubility studies of curcumin and compatibility tests. The formulation of curcumin-loaded SMEDDS was optimized by a simplex lattice experiment design. The optimal formulation of SMEDDS was comprised of 57.5% surfactant (emulsifier OP:Cremorphor EL = 1:1), 30.0% co-surfactant (PEG 400) and 12.5% oil (ethyl oleate). The solubility of curcumin (21 mg/g) significantly increased in SMEDDS. The average particle size of SMEDDS-containing curcumin was about 21 nm when diluted in water. No significant variations in particle size and curcumin content in SMEDDS were observed over a period of 3 months at 4 degrees C. The spherical shape of microemulsion droplet was observed under TEM. The dissolution study in vitro showed that more than 95% of curcumin in SMEDDS could be dissolved in pH 1.2 or pH 6.8 buffer solutions in 20 min, however, less than 2% for crude curcumin in 60 min.The in situ absorption property of curcumin-loaded SMEDDS was evaluated in intestines of rats. The results showed the absorption of curcumin in SMEDDS was via passive transfer by diffusion across the lipid membranes. The results of oral absorption experiment in mice showed that SMEDDS could significantly increase the oral absorption of curcumin compared with its suspension. Our study illustrated that the developed SMEDDS formulation held great potential as a possible alternative to traditional oral formulations of curcumin.

  14. QSO Metal Absorption Systems at High Redshift and the Signature of Hierarchical Galaxy Formation

    NASA Astrophysics Data System (ADS)

    Rauch, Michael; Haehnelt, Martin G.; Steinmetz, Matthias

    1997-05-01

    In a hierarchical cosmogony, galaxies build up by continuous merging of smaller structures. At z = 3, the matter content of a typical present-day galaxy is dispersed over several individual clumps embedded in sheetlike structures, often aligned along filaments. We have used hydrodynamical simulations to investigate the spatial distribution and absorption properties of metal-enriched gas in such regions of ongoing galaxy formation. The metal and hydrogen absorption features produced by the collapsing structures closely resemble observed QSO absorption systems over a wide range in H I column density. Strong C II and Si IV absorption occurs for lines of sight passing the densest regions close to the center of the protogalactic clumps, while C IV is a good tracer of the prominent filamentary structures and O VI becomes the strongest absorption feature for lines of sight passing through low-density regions far away from fully collapsed objects. The observed column density ratios of the different ionic species at z = 3 can be well reproduced if a mean metallicity [Z/H] = -2.5, relative abundances as found in metal-poor stars, a UV background with intensity J-22 = 3 at the Lyman limit, and either a power-law spectrum (J ~ ν-1.5) or the spectral shape proposed by Haardt & Madau are assumed. The observed scatter in [C/H] is about a magnitude larger than that in the simulations, which suggests an inhomogeneous metal distribution. Observed and simulated Doppler parameter distributions of H I and C IV absorption lines are in good agreement, which indicates that shock heating due to gravitational collapse is a second important heating agent in addition to photoionization heating. The large velocity spreads seen in some C IV systems may be due to the occasional alignments of the observer's line of sight with expanding large-scale filaments. Both high-ionization multicomponent heavy-element absorbers and damped Lyα systems can arise from groups of moderately sized protogalactic

  15. GAS AND DUST ABSORPTION IN THE DoAr 24E SYSTEM

    SciTech Connect

    Kruger, Andrew J.; Richter, Matthew J.; Seifahrt, Andreas; Carr, John S.; Najita, Joan R.; Moerchen, Margaret M.; Doppmann, Greg W.

    2012-11-20

    We present findings for DoAr 24E, a binary system that includes a classical infrared companion. We observed the DoAr 24E system with the Spitzer Infrared Spectrograph (IRS), with high-resolution, near-infrared spectroscopy of CO vibrational transitions, and with mid-infrared imaging. The source of high extinction toward infrared companions has been an item of continuing interest. Here we investigate the disk structure of DoAr 24E using the column densities, temperature, and velocity profiles of two CO absorption features seen toward DoAr 24Eb. We model the spectral energy distributions found using T-ReCS imaging and investigate the likely sources of extinction toward DoAr 24Eb. We find the lack of silicate absorption and small CO column density toward DoAr 24Eb suggest that the mid-infrared continuum is not as extinguished as the near-infrared, possibly due to the mid-infrared originating from an extended region. This, along with the velocity profile of the CO absorption, suggests that the source of high extinction is likely due to a disk or disk wind associated with DoAr 24Eb.

  16. Standard addition/absorption detection microfluidic system for salt error-free nitrite determination.

    PubMed

    Ahn, Jae-Hoon; Jo, Kyoung Ho; Hahn, Jong Hoon

    2015-07-30

    A continuous-flow microfluidic chip-based standard addition/absorption detection system has been developed for accurate determination of nitrite in water of varying salinity. The absorption detection of nitrite is made via color development using the Griess reaction. We have found the yield of the reaction is significantly affected by salinity (e.g., -12% error for 30‰ NaCl, 50.0 μg L(-1)N-NO2(-) solution). The microchip has been designed to perform standard addition, color development, and absorbance detection in sequence. To effectively block stray light, the microchip made from black poly(dimethylsiloxane) is placed on the top of a compact housing that accommodates a light-emitting diode, a photomultiplier tube, and an interference filter, where the light source and the detector are optically isolated. An 80-mm liquid-core waveguide mounted on the chip externally has been employed as the absorption detection flow cell. These designs for optics secure a wide linear response range (up to 500 μg L(-1)N-NO2(-)) and a low detection limit (0.12 μg L(-1)N-NO2(-) = 8.6 nM N-NO2(-), S/N = 3). From determination of nitrite in standard samples and real samples collected from an estuary, it has been demonstrated that our microfluidic system is highly accurate (<1% RSD, n = 3) and precise (<1% RSD, n = 3). PMID:26320643

  17. Self-consistent continuum solvation for optical absorption of complex molecular systems in solution

    SciTech Connect

    Timrov, Iurii; Biancardi, Alessandro; Andreussi, Oliviero; Marzari, Nicola; Baroni, Stefano

    2015-01-21

    We introduce a new method to compute the optical absorption spectra of complex molecular systems in solution, based on the Liouville approach to time-dependent density-functional perturbation theory and the revised self-consistent continuum solvation model. The former allows one to obtain the absorption spectrum over a whole wide frequency range, using a recently proposed Lanczos-based technique, or selected excitation energies, using the Casida equation, without having to ever compute any unoccupied molecular orbitals. The latter is conceptually similar to the polarizable continuum model and offers the further advantages of allowing an easy computation of atomic forces via the Hellmann-Feynman theorem and a ready implementation in periodic-boundary conditions. The new method has been implemented using pseudopotentials and plane-wave basis sets, benchmarked against polarizable continuum model calculations on 4-aminophthalimide, alizarin, and cyanin and made available through the QUANTUM ESPRESSO distribution of open-source codes.

  18. Phase-dependent multiple optomechanically induced absorption in multimode optomechanical systems with mechanical driving

    NASA Astrophysics Data System (ADS)

    Jiang, Cheng; Cui, Yuanshun; Bian, Xintian; Zuo, Fen; Yu, Hualing; Chen, Guibin

    2016-08-01

    We investigate theoretically the response of the output field from an optomechanical system consisting of N nearly degenerate mechanical resonators each coupled to a common cavity mode. When the cavity is driven simultaneously by a strong control field and a weak probe field and each mechanical resonator is driven by a coherent mechanical pump, we obtain the analytical expression for the probe transmission. We show that the probe transmission spectrum can exhibit multiple optomechanically induced absorption (OMIA) with at most N narrow absorption dips, which can be tuned by the phase and amplitude of the mechanical driving field as well as the control field. Moreover, it is shown that the peak probe transmission can be enhanced or suppressed by increasing the amplitude of the mechanical pump, which depends on the phase difference. This phase-dependent effect plays an important role in controlling the propagation of the probe field between OMIA and parametric amplification.

  19. Self-consistent continuum solvation for optical absorption of complex molecular systems in solution.

    PubMed

    Timrov, Iurii; Andreussi, Oliviero; Biancardi, Alessandro; Marzari, Nicola; Baroni, Stefano

    2015-01-21

    We introduce a new method to compute the optical absorption spectra of complex molecular systems in solution, based on the Liouville approach to time-dependent density-functional perturbation theory and the revised self-consistent continuum solvation model. The former allows one to obtain the absorption spectrum over a whole wide frequency range, using a recently proposed Lanczos-based technique, or selected excitation energies, using the Casida equation, without having to ever compute any unoccupied molecular orbitals. The latter is conceptually similar to the polarizable continuum model and offers the further advantages of allowing an easy computation of atomic forces via the Hellmann-Feynman theorem and a ready implementation in periodic-boundary conditions. The new method has been implemented using pseudopotentials and plane-wave basis sets, benchmarked against polarizable continuum model calculations on 4-aminophthalimide, alizarin, and cyanin and made available through the Quantum ESPRESSO distribution of open-source codes. PMID:25612693

  20. Space Launch System Base Heating Test: Tunable Diode Laser Absorption Spectroscopy

    NASA Technical Reports Server (NTRS)

    Parker, Ron; Carr, Zak; MacLean, Matthew; Dufrene, Aaron; Mehta, Manish

    2016-01-01

    This paper describes the Tunable Diode Laser Absorption Spectroscopy (TDLAS) measurement of several water transitions that were interrogated during a hot-fire testing of the Space Launch Systems (SLS) sub-scale vehicle installed in LENS II. The temperature of the recirculating gas flow over the base plate was found to increase with altitude and is consistent with CFD results. It was also observed that the gas above the base plate has significant velocity along the optical path of the sensor at the higher altitudes. The line-by-line analysis of the H2O absorption features must include the effects of the Doppler shift phenomena particularly at high altitude. The TDLAS experimental measurements and the analysis procedure which incorporates the velocity dependent flow will be described.

  1. Moisture absorption characteristics of the Orbiter thermal protection system and methods used to prevent water ingestion

    NASA Technical Reports Server (NTRS)

    Schomburg, C.; Dotts, R. L.; Tillian, D. J.

    1983-01-01

    The Space Shuttle Orbiter's silica tile Thermal Protection System (TPS) is beset by the moisture absorption problems inherently associated with low density, highly porous insulation systems. Attention is presently given to the comparative success of methods for the minimization and/or prevention of water ingestion by the TPS tiles, covering the development of water-repellent agents and their tile application techniques, flight test program results, and materials improvements. The use of external films for rewaterproofing of the TPS tiles after each mission have demonstrated marginal to unacceptable performance. By contrast, a tile interior waterproofing agent has shown promise.

  2. Intervening O vi Quasar Absorption Systems at Low Redshift: A Significant Baryon Reservoir.

    PubMed

    Tripp; Savage; Jenkins

    2000-05-01

    Far-UV echelle spectroscopy of the radio-quiet QSO H1821+643 (zem=0.297), obtained with the Space Telescope Imaging Spectrograph (STIS) at approximately 7 km s-1 resolution, reveals four definite O vi absorption-line systems and one probable O vi absorber at 0.15systems unrelated to the background QSO. In the case of the strong O vi system at zabs=0.22497, multiple components are detected in Si iii and O vi as well as H i Lyman series lines, and the differing component velocity centroids and b-values firmly establish that this is a multiphase absorption system. A weak O vi absorber is detected at zabs=0.22637, i.e., offset by approximately 340 km s-1 from the zabs=0.22497 system. Lyalpha absorption is detected at zabs=0.22613, but no Lyalpha absorption is significantly detected at 0.22637. Other weak O vi absorbers at zabs=0.24531 and 0.26659 and the probable O vi system at 0.21326 have widely diverse O vi/H i column density ratios with N(O vi)/N(H i) ranging from systems is Omegab(Ovi&parr0; greater, similar0.0008 h-175. With an assumed metallicity of 1/10 solar and a conservative assumption that the fraction of oxygen in the O vi ionization stage is 0.2, we obtain Omegab(Ovi&parr0; greater, similar0.004 h-175. This is comparable to the combined cosmological mass density of stars and cool gas in galaxies and X-ray-emitting gas in galaxy clusters at low redshift.

  3. An In Silico Knockout Model for Gastrointestinal Absorption Using a Systems Pharmacology Approach - Development and Application for Ketones

    PubMed Central

    Shivva, Vittal; Tucker, Ian G.; Duffull, Stephen B.

    2016-01-01

    Gastrointestinal absorption and disposition of ketones is complex. Recent work describing the pharmacokinetics (PK) of d-β-hydroxybutyrate (BHB) following oral ingestion of a ketone monoester ((R)-3-hydroxybutyl (R)-3-hydroxybutyrate) found multiple input sites, nonlinear disposition and feedback on endogenous production. In the current work, a human systems pharmacology model for gastrointestinal absorption and subsequent disposition of small molecules (monocarboxylic acids with molecular weight < 200 Da) was developed with an application to a ketone monoester. The systems model was developed by collating the information from the literature and knowledge gained from empirical population modelling of the clinical data. In silico knockout variants of this systems model were used to explore the mechanism of gastrointestinal absorption of ketones. The knockouts included active absorption across different regions in the gut and also a passive diffusion knockout, giving 10 gut knockouts in total. Exploration of knockout variants has suggested that there are at least three distinct regions in the gut that contribute to absorption of ketones. Passive diffusion predominates in the proximal gut and active processes contribute to the absorption of ketones in the distal gut. Low doses are predominantly absorbed from the proximal gut by passive diffusion whereas high doses are absorbed across all sites in the gut. This work has provided mechanistic insight into the absorption process of ketones, in the form of unique in silico knockouts that have potential for application with other therapeutics. Future studies on absorption process of ketones are suggested to substantiate findings in this study. PMID:27685985

  4. Absorption enhancement in silicon nanowire-optical nanoantenna system for photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Robak, Elżbieta; Grześkiewicz, Bartłomiej; Kotkowiak, Michał

    2014-11-01

    The rapidly growing green energy sector has prompted the search for new solutions to increase the performance of solar cells. In this area there is still room for the silicon-based photovoltaic, although the main problem is to find a way to increase the efficiency of the silicon solar cells, at the lowest possible cost. In this work we investigate the influence of a gold bowtie nanoantenna on the absorption profile of silicon nanowire. Because of the energy band gap and low effective absorption cross section, bulk silicon absorbs rather poorly in longer wavelengths of visible light and near-infrared range. Our calculations with frequency domain solver show the absorption boost in nanowire at long-wavelengths due to the coupling of the large local near-field of metallic bowtie nanoantenna to the semiconductor layer. The enhancement was observed at various levels although it was correlated with the shift of localized surface plasmon resonance thus making it dependent on the bowtie geometry. The results suggest that by incorporating metallic nanostructures as well as nanoparticles to the nanowire system, the performance of photovoltaic device can be improved thanks to greater generation of a electron-hole pairs.

  5. Enhancement of absorption and hepatoprotective potential through soya-phosphatidylcholine-andrographolide vesicular system.

    PubMed

    Jain, Pushpendra Kumar; Khurana, Navneet; Pounikar, Yogesh; Gajbhiye, Asmita; Kharya, Murli Dhar

    2013-06-01

    Andrographis paniculata is a medicinal herb used extensively for various ailments and contains therapeutically active phytoconstituent, andrographolide (AN). Although hepatoprotective activity of AN is established, but their bioavailability is restricted due to its rapid clearance. The aim of this study, therefore, was to formulate AN herbosomes (ANH) through complexation with naturally occurring soya-phosphatidylcholine (SPC), in order to enhance absorption. Prepared andrographolide-soy phosphatidylcholine (AN-SPC) complex prepared was subjected for characterisation of complex and formation of vesicular system known as ANH using rotary evaporation techniques. This complex was subjected to in vitro study using everted small intestine sac technique which showed significantly increased absorption of AN from the ANH as compared to the plain AN. The hepatoprotective potential of ANH and plain AN was evaluated using carbon tetrachloride inducing hepatotoxicity rat model and compared, in which ANH equivalent to 50 mg/kg of plain AN significantly restore serum glutamate oxalacetate transaminase (112.4 ± 9.67 for AN whereas 90.2 ± 4.23 for ANH) and serum glutamate pyruvate transaminase (109.3 ± 7.89 for AN whereas 90.6 ± 4.34 for ANH) level as compared to control group. The ANH showed significantly better absorption than plain AN and this effect of ANH was also comparable to the standard drug (Silymarin). The findings of present study reveal that ANH has better bioavailability as shown by in vitro absorption study and hence improved hepatoprotection as compared to plain AN at equivalent dose.

  6. Oral delivery system prolongs blood circulation of docetaxel nanocapsules via lymphatic absorption.

    PubMed

    Attili-Qadri, Suha; Karra, Nour; Nemirovski, Alina; Schwob, Ouri; Talmon, Yeshayahu; Nassar, Taher; Benita, Simon

    2013-10-22

    An original oral formulation of docetaxel nanocapsules (NCs) embedded in microparticles elicited in rats a higher bioavailability compared with the i.v. administration of the commercial docetaxel solution, Taxotere. In the present study, various animal studies were designed to elucidate the absorption process of docetaxel from such a delivery system. Again, the docetaxel NC formulation elicited a marked enhanced absorption compared with oral Taxotere in minipigs, resulting in relative bioavailability and Cmax values 10- and 8.4-fold higher, respectively, confirming the previous rat study results. It was revealed that orally absorbed NCs altered the elimination and distribution of docetaxel, as shown in the organ biodistribution rat study, due to their reinforced coating, while transiting through the enterocytes by surface adsorption of apoproteins and phospholipids. These findings were demonstrated by the cryogenic-temperature transmission electron microscopy results and confirmed by the use of a chylomicron flow blocker, cycloheximide, that prevented the oral absorption of docetaxel from the NC formulation in an independent pharmacokinetic study. The lipoproteinated NCs reduced the docetaxel release in plasma and its distribution among the organs. The improved anticancer activity compared with i.v. Taxotere, observed in the metastatic lung cancer model in Severe Combined Immune Deficiency-beige (SCID-bg) mice, should be attributed to the extravasation effect, leading to the lipoproteinated NC accumulation in lung tumors, where they exert a significant therapeutic action. To the best of our knowledge, no study has reported that the absorption of NCs was mediated by a lymphatic process and reinforced during their transit.

  7. [Study of the Detecting System of CH4 and SO2 Based on Spectral Absorption Method and UV Fluorescence Method].

    PubMed

    Wang, Shu-tao; Wang, Zhi-fang; Liu, Ming-hua; Wei, Meng; Chen, Dong-ying; Wang, Xing-long

    2016-01-01

    According to the spectral absorption characteristics of polluting gases and fluorescence characteristics, a time-division multiplexing detection system is designed. Through this system we can detect Methane (CH4) and sulfur dioxide (SO2) by using spectral absorption method and the SO2 can be detected by using UV fluorescence method. The system consists of four parts: a combination of a light source which could be switched, the common optical path, the air chamber and the signal processing section. The spectral absorption characteristics and fluorescence characteristics are measured first. Then the experiment of detecting CH4 and SO2 through spectral absorption method and the experiment of detecting SO2 through UV fluorescence method are conducted, respectively. Through measuring characteristics of spectral absorption and fluorescence, we get excitation wavelengths of SO2 and CH4 measured by spectral absorption method at the absorption peak are 280 nm and 1.64 μm, respectively, and the optimal excitation wavelength of SO2 measured by UV fluorescence method is 220 nm. we acquire the linear relation between the concentration of CH4 and relative intensity and the linear relation between the concentration of SO2 and output voltage after conducting the experiment of spectral absorption method, and the linearity are 98.7%, 99.2% respectively. Through the experiment of UV fluorescence method we acquire that the relation between the concentration of SO2 and the voltage is linear, and the linearity is 99.5%. Research shows that the system is able to be applied to detect the polluted gas by absorption spectrum method and UV fluorescence method. Combing these two measurement methods decreases the costing and the volume, and this system can also be used to measure the other gases. Such system has a certain value of application. PMID:27228784

  8. [Study of the Detecting System of CH4 and SO2 Based on Spectral Absorption Method and UV Fluorescence Method].

    PubMed

    Wang, Shu-tao; Wang, Zhi-fang; Liu, Ming-hua; Wei, Meng; Chen, Dong-ying; Wang, Xing-long

    2016-01-01

    According to the spectral absorption characteristics of polluting gases and fluorescence characteristics, a time-division multiplexing detection system is designed. Through this system we can detect Methane (CH4) and sulfur dioxide (SO2) by using spectral absorption method and the SO2 can be detected by using UV fluorescence method. The system consists of four parts: a combination of a light source which could be switched, the common optical path, the air chamber and the signal processing section. The spectral absorption characteristics and fluorescence characteristics are measured first. Then the experiment of detecting CH4 and SO2 through spectral absorption method and the experiment of detecting SO2 through UV fluorescence method are conducted, respectively. Through measuring characteristics of spectral absorption and fluorescence, we get excitation wavelengths of SO2 and CH4 measured by spectral absorption method at the absorption peak are 280 nm and 1.64 μm, respectively, and the optimal excitation wavelength of SO2 measured by UV fluorescence method is 220 nm. we acquire the linear relation between the concentration of CH4 and relative intensity and the linear relation between the concentration of SO2 and output voltage after conducting the experiment of spectral absorption method, and the linearity are 98.7%, 99.2% respectively. Through the experiment of UV fluorescence method we acquire that the relation between the concentration of SO2 and the voltage is linear, and the linearity is 99.5%. Research shows that the system is able to be applied to detect the polluted gas by absorption spectrum method and UV fluorescence method. Combing these two measurement methods decreases the costing and the volume, and this system can also be used to measure the other gases. Such system has a certain value of application.

  9. THE DISAPPEARANCE OF A NARROW Mg II ABSORPTION SYSTEM IN QUASAR SDSS J165501.31+260517.4

    SciTech Connect

    Chen Zhifu; Qin Yiping; Gu Minfeng E-mail: ypqin@126.com

    2013-06-10

    In this paper, we present for the first time the discovery of the disappearance of a narrow Mg II {lambda}{lambda}2796, 2803 absorption system from the spectra of the quasar SDSS J165501.31+260517.4 (z{sub e} = 1.8671). This absorber is located at z{sub abs} = 1.7877 and has a velocity offset of 8423 km s{sup -1} with respect to the quasar. According to the velocity offset and the line variability, this narrow Mg II {lambda}{lambda}2796, 2803 absorption system is likely intrinsic to the quasar. Since the corresponding UV continuum emission and the absorption lines of another narrow Mg II {lambda}{lambda}2796, 2803 absorption system at z{sub abs} = 1.8656 are very stable, we believe that the disappearance of the absorption system is unlikely to be caused by the change in ionization of absorption gas. Instead, it likely arises from the motion of the absorption gas across the line of sight.

  10. The Physical Nature of Weak MgII Quasar Absorption Line Systems.

    NASA Astrophysics Data System (ADS)

    Narayanan, Anand

    2007-12-01

    In a span of four decades, quasar absorption line spectroscopy has emerged as one of the most efficient methods for probing HI gas and associated metals in a wide range of environments, from redshifts corresponding to the most distant quasars up to the present. The connection between strong MgII quasar absorption systems and the disks/halos of galaxies of various morphologies is fairly well established. In contrast, the physical nature of weak MgII absorbers is not sufficiently understood. In this talk, I will present results from my dissertation work, which is a study of weak MgII quasar absorption line systems at 0systems these absorbers might correspond to. A significant population of weak MgII clouds, identified at high redshift (z >1), could be gas clouds in the extended halos of galaxies, analogous to the Milky Way high velocity clouds. The gas might correspond to material expelled from rapidly star-forming galaxies in correlated supernova events. Some fraction of the population of weak MgII clouds can also arise along sight lines that intercept tidally stripped interstellar gas, residing in circumgalactic environments. The `iron-rich’ weak MgII clouds, which are prevalent at lower redshifts (z<1), must be tracing Type Ia enriched gas in sites that have been previously enriched by star formation, most likely in dwarf galaxies. These scenarios will be reviewed in my presentation. This work is supported by NSF. I thankfully acknowledge the Zaccheus Daniel Foundation and Sigma Xi for providing generous travel support.

  11. Implications of a primordial origin for the dispersion in D/H in quasar absorption systems

    PubMed Central

    Copi, Craig J.; Olive, Keith A.; Schramm, David N.

    1998-01-01

    We explore the difficulties with a primordial origin of variations of D/H in quasar absorption systems. In particular we examine options such as a very large-scale inhomogeneity in the baryon content of the universe. We show that very large-scale (much larger than 1 Mpc) isocurvature perturbations are excluded by current cosmic microwave background observations. Smaller-scale ad hoc perturbations (∼1 Mpc) still may lead to a large dispersion in primordial abundances but are subject to other constraints. PMID:9501162

  12. Electromagnetically induced absorption via spontaneously generated coherence of a Λ system

    NASA Astrophysics Data System (ADS)

    Liu, Cheng-pu; Gong, Shang-qing; Fan, Xi-jun; Xu, Zhi-zhan

    2004-02-01

    The effect of spontaneously generated coherence (SGC) on the pump-probe response of a nearly degenerate Λ system is investigated by taking into account the dephasing of the low-frequency coherence. It is found, in the case of small dephasing, that instead of electromagnetically induced transparency (EIT) at resonance, electromagnetically induced absorption (EIA) can occur due to the effect of SGC. We also study the effect of relative phase between the two applied fields and find that EIA and EIT can transform mutually by adjusting the relative phase.

  13. Implications of a primordial origin for the dispersion in D/H in quasar absorption systems.

    PubMed

    Copi, C J; Olive, K A; Schramm, D N

    1998-03-17

    We explore the difficulties with a primordial origin of variations of D/H in quasar absorption systems. In particular we examine options such as a very large-scale inhomogeneity in the baryon content of the universe. We show that very large-scale (much larger than 1 Mpc) isocurvature perturbations are excluded by current cosmic microwave background observations. Smaller-scale ad hoc perturbations (approximately 1 Mpc) still may lead to a large dispersion in primordial abundances but are subject to other constraints.

  14. Transient absorption spectroscopy detection of sensitized delayed fluorescence in chiral benzophenone/naphthalene systems

    NASA Astrophysics Data System (ADS)

    Bonancía, Paula; Jiménez, M. Consuelo; Miranda, Miguel A.

    2011-10-01

    Transient absorption spectroscopy has proven to be a powerful tool to investigate the formation and decay of excited singlet states upon triplet-triplet annihilation, following T-T energy transfer from a selectively excited sensitizer. Thus, upon selective excitation of benzophenone (BZP) by laser flash photolysis (LFP) at λ = 355 nm in the presence of naphthalene (NPT), a negative band centered at 340 nm has been detected, with growth and decay in the microsecond timescale. It has been assigned to the P-type NPT delayed-fluorescence. In the case of chiral BZP/NPT systems, stereodifferentiation has been observed in the kinetics of the involved photophysical processes.

  15. X-ray absorption spectroscopy on magnetic nanoscale systems for modern applications

    NASA Astrophysics Data System (ADS)

    Schmitz-Antoniak, Carolin

    2015-06-01

    X-ray absorption spectroscopy facilitated by state-of-the-art synchrotron radiation technology is presented as a powerful tool to study nanoscale systems, in particular revealing their static element-specific magnetic and electronic properties on a microscopic level. A survey is given on the properties of nanoparticles, nanocomposites and thin films covering a broad range of possible applications. It ranges from the ageing effects of iron oxide nanoparticles in dispersion for biomedical applications to the characterisation on a microscopic level of nanoscale systems for data storage devices. In this respect, new concepts for electrically addressable magnetic data storage devices are highlighted by characterising the coupling in a BaTiO3/CoFe2O4 nanocomposite as prototypical model system. But classical magnetically addressable devices are also discussed on the basis of tailoring the magnetic properties of self-assembled ensembles of FePt nanoparticles for data storage and the high-moment material Fe/Cr/Gd for write heads. For the latter cases, the importance is emphasised of combining experimental approaches in x-ray absorption spectroscopy with density functional theory to gain a more fundamental understanding.

  16. Enhanced dissolution and oral absorption of tacrolimus by supersaturable self-emulsifying drug delivery system

    PubMed Central

    Lee, Dae Ro; Ho, Myoung Jin; Jung, Hyuck Jun; Cho, Ha Ra; Park, Jun Seo; Yoon, Suk-Hyun; Choi, Yong Seok; Choi, Young Wook; Oh, Chung-Hun; Kang, Myung Joo

    2016-01-01

    A new Soluplus (polyvinyl caprolactam–polyvinyl acetate–polyethylene glycol graft copolymer)-based supersaturable self-emulsifying drug delivery system (S-SEDDS) was formulated to enhance oral absorption of tacrolimus (FK506) with minimal use of oil, surfactant, and cosurfactant. A high payload supersaturable system (S-SEDDS) was prepared by incorporating Soluplus, as a precipitation inhibitor, to SEDDS consisting of Capmul MCM, Cremophor EL, and Transcutol (FK506:vehicle:Soluplus =1:15:1). In vitro dissolution profile and in vitro pharmacokinetic aspect of S-SEDDS in rats were comparatively evaluated with those of conventional SEDDS formulas containing four times greater content of vehicle components (FK506:vehicle =1:60). Both formulations formed spherical drug-loaded microemulsion <70 nm in size when in contact with aqueous medium. In an in vitro dissolution test in a nonsink condition, the amphiphilic polymer noticeably retarded drug precipitation and maintained >80% of accumulated dissolution rate for 24 hours, analogous to that from conventional SEDDS. Moreover, pharmacokinetic parameters of the maximum blood concentration and area under the curve from S-SEDDS formula in rats were not statistically different (P>0.05) than those of conventional SEDDS. The results suggest that the Soluplus-based supersaturable system can be an alternative to achieve a comparable in vitro dissolution profile and in vivo oral absorption with conventional SEDDS, with minimal use of vehicle ingredients. PMID:27051286

  17. Enhanced dissolution and oral absorption of tacrolimus by supersaturable self-emulsifying drug delivery system.

    PubMed

    Lee, Dae Ro; Ho, Myoung Jin; Jung, Hyuck Jun; Cho, Ha Ra; Park, Jun Seo; Yoon, Suk-Hyun; Choi, Yong Seok; Choi, Young Wook; Oh, Chung-Hun; Kang, Myung Joo

    2016-01-01

    A new Soluplus (polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer)-based supersaturable self-emulsifying drug delivery system (S-SEDDS) was formulated to enhance oral absorption of tacrolimus (FK506) with minimal use of oil, surfactant, and cosurfactant. A high payload supersaturable system (S-SEDDS) was prepared by incorporating Soluplus, as a precipitation inhibitor, to SEDDS consisting of Capmul MCM, Cremophor EL, and Transcutol (FK506:vehicle:Soluplus =1:15:1). In vitro dissolution profile and in vitro pharmacokinetic aspect of S-SEDDS in rats were comparatively evaluated with those of conventional SEDDS formulas containing four times greater content of vehicle components (FK506:vehicle =1:60). Both formulations formed spherical drug-loaded microemulsion <70 nm in size when in contact with aqueous medium. In an in vitro dissolution test in a nonsink condition, the amphiphilic polymer noticeably retarded drug precipitation and maintained >80% of accumulated dissolution rate for 24 hours, analogous to that from conventional SEDDS. Moreover, pharmacokinetic parameters of the maximum blood concentration and area under the curve from S-SEDDS formula in rats were not statistically different (P>0.05) than those of conventional SEDDS. The results suggest that the Soluplus-based supersaturable system can be an alternative to achieve a comparable in vitro dissolution profile and in vivo oral absorption with conventional SEDDS, with minimal use of vehicle ingredients. PMID:27051286

  18. H I-SELECTED GALAXIES AS A PROBE OF QUASAR ABSORPTION SYSTEMS

    SciTech Connect

    Okoshi, Katsuya; Nagashima, Masahiro; Gouda, Naoteru; Minowa, Yousuke

    2010-02-20

    We investigate the properties of H I-rich galaxies detected in blind radio surveys within the hierarchical structure formation scenario using a semianalytic model of galaxy formation. By drawing a detailed comparison between the properties of H I-selected galaxies and H I absorption systems, we argue a link between the local galaxy population and quasar absorption systems, particularly for damped Lyalpha absorption (DLA) systems and sub-DLA systems. First, we evaluate how many H I-selected galaxies exhibit H I column densities as high as those of DLA systems. We find that H I-selected galaxies with H I masses M{sub H{sub I}} {approx}> 10{sup 8} M{sub sun} have gaseous disks that produce H I column densities comparable to those of DLA systems. We conclude that DLA galaxies where the H I column densities are as high as those of DLA systems, contribute significantly to the population of H I-selected galaxies at M{sub H{sub I}} {approx}> 10{sup 8} M{sub sun}. Second, we find that star formation rates (SFRs) correlate tightly with H I masses (M{sub H{sub I}}) rather than B- (and J-) band luminosities: SFR {proportional_to} M {sup alpha}{sub H{sub I}}, alpha = 1.25-1.40 for 10{sup 6} <= M{sub H{sub I}}/M{sub sun} <= 10{sup 11}. In the low-mass range M{sub H{sub I}} {approx}< 10{sup 8} M{sub sun}, sub-DLA galaxies replace DLA galaxies as the dominant population. The number fraction of sub-DLA galaxies relative to galaxies reaches 40%-60% for M{sub H{sub I}} {approx} 10{sup 8} M{sub sun} and 30%-80% for M{sub H{sub I}} {approx} 10{sup 7} M{sub sun}. The H I-selected galaxies at M{sub H{sub I}} {approx} 10{sup 7} M{sub sun} are a strong probe of sub-DLA systems that place stringent constraints on galaxy formation and evolution.

  19. NEAR-ULTRAVIOLET ABSORPTION, CHROMOSPHERIC ACTIVITY, AND STAR-PLANET INTERACTIONS IN THE WASP-12 SYSTEM

    SciTech Connect

    Haswell, C. A.; Fossati, L.; Holmes, S.; Kolb, U. C.; Busuttil, R.; Carter, A.; Ayres, T.; France, K.; Froning, C. S.; Street, R. A.; Hebb, L.; Cameron, A. Collier; Enoch, B.; Burwitz, V.; Rodriguez, J.; West, R. G.; Pollacco, D.; Wheatley, P. J. E-mail: l.fossati@open.ac.uk E-mail: leslie.hebb@vanderbilt.edu

    2012-11-20

    Extended gas clouds have been previously detected surrounding the brightest known close-in transiting hot Jupiter exoplanets, HD 209458 b and HD 189733 b; we observed the distant but more extreme close-in hot Jupiter system, WASP-12, with Hubble Space Telescope (HST). Near-UV (NUV) transits up to three times deeper than the optical transit of WASP-12 b reveal extensive diffuse gas, extending well beyond the Roche lobe. The distribution of absorbing gas varies between visits. The deepest NUV transits are at wavelength ranges with strong stellar photospheric absorption, implying that the absorbing gas may have temperature and composition similar to those of the stellar photosphere. Our spectra reveal significantly enhanced absorption (greater than 3{sigma} below the median) at {approx}200 individual wavelengths on each of two HST visits; 65 of these wavelengths are consistent between the two visits, using a strict criterion for velocity matching that excludes matches with velocity shifts exceeding {approx}20 km s{sup -1}. Excess transit depths are robustly detected throughout the inner wings of the Mg II resonance lines independently on both HST visits. We detected absorption in Fe II {lambda}2586, the heaviest species yet detected in an exoplanet transit. The Mg II line cores have zero flux, emission cores exhibited by every other observed star of similar age and spectral type are conspicuously absent. WASP-12 probably produces normal Mg II profiles, but the inner portions of these strong resonance lines are likely affected by extrinsic absorption. The required Mg{sup +} column is an order of magnitude greater than expected from the interstellar medium, though we cannot completely dismiss that possibility. A more plausible source of absorption is gas lost by WASP-12 b. We show that planetary mass loss can produce the required column. Our Visit 2 NUV light curves show evidence for a stellar flare. We show that some of the possible transit detections in resonance

  20. Radio line and continuum observations of quasar-galaxy pairs and the origin of low reshift quasar absorption line systems

    NASA Technical Reports Server (NTRS)

    Carilli, C. L.; Vangorkom, J. H.; Hauxthausen, E. M.; Stocke, J. T.; Salzer, J.

    1990-01-01

    There are a number of known quasars for which our line of sight to the high redshift quasar passes within a few Holmberg radii of a low redshift galaxy. In a few of these cases, spectra of the quasar reveal absorption by gas associated with the low redshift galaxy. A number of these pairs imply absorption by gas which lies well outside the optical disk of the associated galaxy, leading to models of galaxies with 'halos' or 'disks' of gas extending to large radii. The authors present observations of 4 such pairs. In three of the four cases, they find that the associated galaxy is highly disturbed, typically due to a gravitational interaction with a companion galaxy, while in the fourth case the absorption can be explained by clouds in the optical disk of the associated galaxy. They are led to an alternative hypothesis concerning the origin of the low redshift absorption line systems: the absorption is by gas clouds which have been gravitationally stripped from the associated galaxy. These galaxies are rapidly evolving, and should not be used as examples of absorption by clouds in halos of field spirals. The authors conclude by considering the role extended gas in interacting systems plays in the origin of higher redshift quasar absorption line systems.

  1. Absorption-line systems in simulated galaxies fed by cold streams

    NASA Astrophysics Data System (ADS)

    Fumagalli, Michele; Prochaska, J. Xavier; Kasen, Daniel; Dekel, Avishai; Ceverino, Daniel; Primack, Joel R.

    2011-12-01

    Hydro-cosmological simulations reveal that massive galaxies at high redshift are fed by long narrow streams of merging galaxies and a smoother component of cold gas. We post-process seven high-resolution simulated galaxies with radiative transfer to study the absorption characteristics of the gas in galaxies and streams, in comparison with the statistics of observed absorption-line systems. We find that much of the stream gas is ionized by UV radiation from background and local stellar sources, but still optically thick (? cm-2) so that the streams appear as Lyman-limit systems (LLSs). At z > 3, the fraction of neutral gas in streams becomes non-negligible, giving rise to damped Lyman α absorbers (DLAs) as well. The gas in the central and incoming galaxies remains mostly neutral, responsible for DLAs. Within one (two) virial radii, the covering factor of optically thick gas is <25 per cent (10 per cent) for LLSs and <5 per cent (1 per cent) for DLAs, slowly declining with time following the universal expansion. Nevertheless, galaxies and their cold streams in the studied mass range, Mvir= 1010-1012 M⊙, account for >30 per cent of the observed absorbers in the foreground of quasars, the rest possibly arising from smaller galaxies or the intergalactic medium. The mean metallicity in the streams is ˜1 per cent solar, much lower than in the galaxies. The simulated galaxies reproduce the Lyα-absorption equivalent widths observed around Lyman-break galaxies, but they severely underpredict the equivalent widths in metal lines, suggesting that the latter may arise from outflows. We conclude that the observed metal-poor LLSs are likely detections of the predicted cold streams. Revised analysis of the observed LLSs kinematics and simulations with more massive outflows in conjunction with the inflows may enable a clearer distinction between the signatures of the various gas modes.

  2. Optical absorption enhancement in a hybrid system photonic crystal - thin substrate for photovoltaic applications.

    PubMed

    Buencuerpo, Jeronimo; Munioz-Camuniez, Luis E; Dotor, Maria L; Postigo, Pablo A

    2012-07-01

    A hybrid approach for light trapping using photonic crystal nanostructures (nanorods, nanopillars or nanoholes) on top of an ultra thin film as a substrate is presented. The combination of a nanopatterned layer with a thin substrate shows an enhanced optical absorption than equivalent films without patterning and can compete in performance with nanostructured systems without a substrate. The designs are tested in four relevant materials: amorphous silicon (a-Si), crystalline silicon (Si), gallium arsenide (GaAs) and indium phosphide (InP). A consistent enhancement is observed for all of the materials when using a thin hybrid system (300 nm) even compared to the non patterned thin film with an anti-reflective coating (ARC). A realistic solar cell structure composed of a hybrid system with a layer of indium tin oxide (ITO) an ARC and a back metal layer is performed, showing an 18% of improvement for the nanostructured device. PMID:22828614

  3. Quick-look system of auroral absorption images by imaging riometer

    NASA Astrophysics Data System (ADS)

    Sato, Mitsugi; Yamagishi, Hisao; Kato, Yasuo; Nishino, Masanori

    1992-07-01

    Imaging riometer of two-dimensional multi-narrow beams is a powerful radio instrument to investigate the structure of CNA (Cosmic Noise Absorption) in the auroral ionosphere caused by the precipitation of energetic electrons. However, the instrument has a demerit of delay-look for imaging because of the use of a large capacity computer for data processing. QL (Quick-Look) system of the imaging riometer was developed by using a personal computer. This system has a function to view the CNA images in real time. QDC's (Quiet Day Curves) which indicate the condition of quiet ionosphere are determined from daily variations of cosmic noise intensity obtained during the initial ten days. Thereafter the QDC's are set into real-time data processing as a reference. The QL system has an advantage for real-time comparison with auroral images by the all-sky TV (Television) camera.

  4. Some heat pump concepts for residual heat utilization. [Absorption-cycle and open-cycle systems

    SciTech Connect

    Perez-Blanco, H.; Chen, F. C.

    1980-01-01

    Large quantities of low temperature heat in the industrial sector are rejected in the cooling water, condensate, and process water streams. While the energy rejected in these streams at temperatures between 40 and 80/sup 0/C amounts to 2.95 x 10/sup 9/ GJ/y, 2.42 x 10/sup 9/ GJ/y of process energy in the form of hot water and steam are needed in the United States. Industrial heat pumps, that recover the low temperature heat energy and upgrade it to a more usable temperature level, may improve the energy supply and demand situation. Two heat activated heat pump concepts - an absorption cycle system and an open cycle system are analyzed from the conceptual systems design and energy savings point of view. The results of the analysis and further research needs are presented.

  5. Optical absorption enhancement in a hybrid system photonic crystal - thin substrate for photovoltaic applications.

    PubMed

    Buencuerpo, Jeronimo; Munioz-Camuniez, Luis E; Dotor, Maria L; Postigo, Pablo A

    2012-07-01

    A hybrid approach for light trapping using photonic crystal nanostructures (nanorods, nanopillars or nanoholes) on top of an ultra thin film as a substrate is presented. The combination of a nanopatterned layer with a thin substrate shows an enhanced optical absorption than equivalent films without patterning and can compete in performance with nanostructured systems without a substrate. The designs are tested in four relevant materials: amorphous silicon (a-Si), crystalline silicon (Si), gallium arsenide (GaAs) and indium phosphide (InP). A consistent enhancement is observed for all of the materials when using a thin hybrid system (300 nm) even compared to the non patterned thin film with an anti-reflective coating (ARC). A realistic solar cell structure composed of a hybrid system with a layer of indium tin oxide (ITO) an ARC and a back metal layer is performed, showing an 18% of improvement for the nanostructured device.

  6. 41 CFR 102-41.205 - Do we report all forfeited distilled spirits, wine, and beer to GSA for disposal?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... forfeited distilled spirits, wine, and beer to GSA for disposal? 102-41.205 Section 102-41.205 Public..., and Beer § 102-41.205 Do we report all forfeited distilled spirits, wine, and beer to GSA for disposal? (a) Yes, except do not report distilled spirits, wine, and beer not fit for human consumption or...

  7. 41 CFR 102-41.205 - Do we report all forfeited distilled spirits, wine, and beer to GSA for disposal?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... forfeited distilled spirits, wine, and beer to GSA for disposal? 102-41.205 Section 102-41.205 Public..., and Beer § 102-41.205 Do we report all forfeited distilled spirits, wine, and beer to GSA for disposal? (a) Yes, except do not report distilled spirits, wine, and beer not fit for human consumption or...

  8. 41 CFR 102-41.205 - Do we report all forfeited distilled spirits, wine, and beer to GSA for disposal?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... forfeited distilled spirits, wine, and beer to GSA for disposal? 102-41.205 Section 102-41.205 Public..., and Beer § 102-41.205 Do we report all forfeited distilled spirits, wine, and beer to GSA for disposal? (a) Yes, except do not report distilled spirits, wine, and beer not fit for human consumption or...

  9. 41 CFR 102-41.205 - Do we report all forfeited distilled spirits, wine, and beer to GSA for disposal?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... forfeited distilled spirits, wine, and beer to GSA for disposal? 102-41.205 Section 102-41.205 Public..., and Beer § 102-41.205 Do we report all forfeited distilled spirits, wine, and beer to GSA for disposal? (a) Yes, except do not report distilled spirits, wine, and beer not fit for human consumption or...

  10. 41 CFR 102-41.205 - Do we report all forfeited distilled spirits, wine, and beer to GSA for disposal?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... forfeited distilled spirits, wine, and beer to GSA for disposal? 102-41.205 Section 102-41.205 Public..., and Beer § 102-41.205 Do we report all forfeited distilled spirits, wine, and beer to GSA for disposal? (a) Yes, except do not report distilled spirits, wine, and beer not fit for human consumption or...

  11. 41 CFR 102-117.340 - What other types of assistance may GSA provide agencies in dealing with regulatory bodies?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... assistance may GSA provide agencies in dealing with regulatory bodies? 102-117.340 Section 102-117.340 Public... MANAGEMENT REGULATION TRANSPORTATION 117-TRANSPORTATION MANAGEMENT Representation Before Regulatory Body... bodies? (a) GSA has oversight of all public utilities used by the Federal Government...

  12. 41 CFR 102-117.340 - What other types of assistance may GSA provide agencies in dealing with regulatory bodies?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... assistance may GSA provide agencies in dealing with regulatory bodies? 102-117.340 Section 102-117.340 Public... MANAGEMENT REGULATION TRANSPORTATION 117-TRANSPORTATION MANAGEMENT Representation Before Regulatory Body... bodies? (a) GSA has oversight of all public utilities used by the Federal Government...

  13. 41 CFR 102-73.85 - Can agencies with independent statutory authority to lease space have GSA perform the leasing...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... independent statutory authority to lease space have GSA perform the leasing functions? 102-73.85 Section 102...-73.85 Can agencies with independent statutory authority to lease space have GSA perform the leasing... space, and land incidental thereto, for Federal agencies possessing independent statutory authority...

  14. 76 FR 13617 - Office of Federal High-Performance Green Buildings (OFHPGB); Notice of GSA Bulletin OFHPGB 2011...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-14

    ... found at http://www.gsa.gov/portal/content/221677 . DATES: Effective March 14, 2011. FOR FURTHER... Buildings.'' Notice 2008-40 can be found at http://www.irs.gov/irb/2008-14_IRB/ar12.html . For clarification... Green Building are located on the Internet at http://www.gsa.gov/portal/content/105239 as...

  15. 41 CFR 102-36.145 - May we obtain excess personal property directly from another Federal agency without GSA approval?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... personal property directly from another Federal agency without GSA approval? 102-36.145 Section 102-36.145... property directly from another Federal agency without GSA approval? Yes, but only under the following... conditions in § 102-36.75(b) applies. (d) You may obtain excess personal property directly from...

  16. 41 CFR 102-36.145 - May we obtain excess personal property directly from another Federal agency without GSA approval?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... personal property directly from another Federal agency without GSA approval? 102-36.145 Section 102-36.145... property directly from another Federal agency without GSA approval? Yes, but only under the following... conditions in § 102-36.75(b) applies. (d) You may obtain excess personal property directly from...

  17. 41 CFR 102-72.105 - What are the requirements for obtaining a utility services delegation of authority from GSA?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... requirements for obtaining a utility services delegation of authority from GSA? 102-72.105 Section 102-72.105....105 What are the requirements for obtaining a utility services delegation of authority from GSA? Executive agencies may be delegated utility services authority when they have the technical expertise...

  18. 41 CFR 102-36.305 - May we abandon or destroy excess personal property without reporting it to GSA?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... destroy excess personal property without reporting it to GSA? 102-36.305 Section 102-36.305 Public... without reporting it to GSA? Yes, you may abandon or destroy excess personal property when you have made a... when it has neither utility nor monetary value (either as an item or as scrap)....

  19. Investigation of absorption and scattering characteristics of kiwifruit tissue using a single integrating sphere system*

    PubMed Central

    Fang, Zhen-huan; Fu, Xia-ping; He, Xue-ming

    2016-01-01

    For a quantitative understanding of light interaction with fruit tissue, it is critical to obtain two fundamental parameters: the absorption coefficient and the scattering coefficient of the tissue. This study was to investigate the optical properties of kiwifruit tissue at the wavelength of 632.8 nm. The total reflectance and total transmittance of kiwifruit tissue from three parts (including the flesh part, the seed part, and the seed-base part) were measured using a single integrating sphere system. Based on the measured spectral signals, the absorption coefficient μ a and the reduced scattering coefficient μ s' of kiwifruit tissue were calculated using the inverse adding-doubling (IAD) method. Phantoms made from Intralipid 20% and India ink as well as a Biomimic solid phantom were used for system validation. The mean values of μ a and μ s' of different parts of the kiwifruit were 0.031–0.308 mm−1 and 0.120–0.946 mm−1, respectively. The results showed significant differences among the μ a and μ s' of the three parts of the kiwifruit. The results of this study confirmed the importance of studying the optical properties for a quantitative understanding of light interaction with fruit tissue. Further investigation of fruit optical properties will be extended to a broader spectral region and different kinds of fruits. PMID:27256682

  20. Investigation of absorption and scattering characteristics of kiwifruit tissue using a single integrating sphere system.

    PubMed

    Fang, Zhen-Huan; Fu, Xia-Ping; He, Xue-Ming

    2016-06-01

    For a quantitative understanding of light interaction with fruit tissue, it is critical to obtain two fundamental parameters: the absorption coefficient and the scattering coefficient of the tissue. This study was to investigate the optical properties of kiwifruit tissue at the wavelength of 632.8 nm. The total reflectance and total transmittance of kiwifruit tissue from three parts (including the flesh part, the seed part, and the seed-base part) were measured using a single integrating sphere system. Based on the measured spectral signals, the absorption coefficient μa and the reduced scattering coefficient μs' of kiwifruit tissue were calculated using the inverse adding-doubling (IAD) method. Phantoms made from Intralipid 20% and India ink as well as a Biomimic solid phantom were used for system validation. The mean values of μa and μs' of different parts of the kiwifruit were 0.031-0.308 mm(-1) and 0.120-0.946 mm(-1), respectively. The results showed significant differences among the μa and μs' of the three parts of the kiwifruit. The results of this study confirmed the importance of studying the optical properties for a quantitative understanding of light interaction with fruit tissue. Further investigation of fruit optical properties will be extended to a broader spectral region and different kinds of fruits. PMID:27256682

  1. The ultraviolet absorption spectrum of the quasar PKS 0405-12 and the local density of Lyman-alpha absorption systems

    NASA Technical Reports Server (NTRS)

    Bahcall, John N.; Jannuzi, Buell T.; Schneider, Donald P.; Hartig, George F.

    1993-01-01

    A sample of 32 absorption lines has been identified in the ultraviolet spectrum of the z = 0.57 quasar PKS 0405-12. Data cover the wavelength range 1190-3260 A. There are 10 extragalactic Ly-alpha absorption lines in the complete sample, all with observed equivalent widths greater than or equal to 0.40 A; three of the Ly-alpha lines have Ly-beta counterparts. The number of Ly-alpha lines observed in the spectrum of PKS 0405-12 is within 1 sigma of the number predicted on the basis of previous HST observations of 3C 273 and of H1821 + 643. Combining the HST observations of 3C 273, H1821 + 643, and PKS 0405-12, we estimate the local number density of Ly-alpha systems with rest equivalent widths larger than 0.32 A to be about 15 +/- 4 Ly-alpha lines per unit redshift. Ground-based images reveal a rich field of galaxies in the direction of PKS 0405-12, including many galaxies with the brightnesses and sizes expected if they belong to a cluster associated with the quasar. The quasar spectrum does not show any evidence for absorption at the redshift of the emission lines, indicating a covering factor of less than unity for the halos of galaxies in the cluster around PKS 0405 - 12.

  2. Development and testing of a frequency-agile optical parametric oscillator system for differential absorption lidar

    NASA Astrophysics Data System (ADS)

    Weibring, P.; Smith, J. N.; Edner, H.; Svanberg, S.

    2003-10-01

    An all-solid-state fast-tuning lidar transmitter for range- and temporally resolved atmospheric gas concentration measurements has been developed and thoroughly tested. The instrument is based on a commercial optical parametric oscillator (OPO) laser system, which has been redesigned with piezoelectric transducers mounted on the wavelength-tuning mirror and on the crystal angle tuning element in the OPO. Piezoelectric transducers similarly control a frequency-mixing stage and doubling stage, which have been incorporated to extend system capabilities to the mid-IR and UV regions. The construction allows the system to be tuned to any wavelength, in any order, in the range of the piezoelectric transducers on a shot-to-shot basis. This extends the measurement capabilities far beyond the two-wavelength differential absorption lidar method and enables simultaneous measurements of several gases. The system performance in terms of wavelength, linewidth, and power stability is monitored in real time by an étalon-based wave meter and gas cells. The tests showed that the system was able to produce radiation in the 220-4300-nm-wavelength region, with an average linewidth better than 0.2 cm-1 and a shot-to-shot tunability up to 160 cm-1 within 20 ms. The utility of real-time linewidth and wavelength measurements is demonstrated by the ability to identify occasional poor quality laser shots and disregard these measurements. Also, absorption cell measurements of methane and mercury demonstrate the performance in obtaining stable wavelength and linewidth during rapid scans in the mid-IR and UV regions.

  3. 41 CFR 102-33.385 - Is any civilian executive agency exempt from the requirement to report information to GSA on...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... executive agency exempt from the requirement to report information to GSA on Government aircraft? 102-33.385... requirement to report information to GSA on Government aircraft? No civilian executive agency is exempt.... intelligence agencies are exempt from the requirement to report to GSA on Government aircraft....

  4. 41 CFR 102-33.385 - Is any civilian executive agency exempt from the requirement to report information to GSA on...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... executive agency exempt from the requirement to report information to GSA on Government aircraft? 102-33.385... requirement to report information to GSA on Government aircraft? No civilian executive agency is exempt.... intelligence agencies are exempt from the requirement to report to GSA on Government aircraft....

  5. 41 CFR 102-33.385 - Is any civilian executive agency exempt from the requirement to report information to GSA on...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... executive agency exempt from the requirement to report information to GSA on Government aircraft? 102-33.385... requirement to report information to GSA on Government aircraft? No civilian executive agency is exempt.... intelligence agencies are exempt from the requirement to report to GSA on Government aircraft....

  6. 41 CFR 102-33.385 - Is any civilian executive agency exempt from the requirement to report information to GSA on...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... executive agency exempt from the requirement to report information to GSA on Government aircraft? 102-33.385... requirement to report information to GSA on Government aircraft? No civilian executive agency is exempt.... intelligence agencies are exempt from the requirement to report to GSA on Government aircraft....

  7. 41 CFR 102-34.220 - What does GSA do if it learns of unofficial use of a Government motor vehicle?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What does GSA do if it learns of unofficial use of a Government motor vehicle? 102-34.220 Section 102-34.220 Public Contracts....220 What does GSA do if it learns of unofficial use of a Government motor vehicle? GSA reports...

  8. 41 CFR 102-34.220 - What does GSA do if it learns of unofficial use of a Government motor vehicle?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What does GSA do if it learns of unofficial use of a Government motor vehicle? 102-34.220 Section 102-34.220 Public Contracts....220 What does GSA do if it learns of unofficial use of a Government motor vehicle? GSA reports...

  9. 41 CFR 102-34.220 - What does GSA do if it learns of unofficial use of a Government motor vehicle?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What does GSA do if it learns of unofficial use of a Government motor vehicle? 102-34.220 Section 102-34.220 Public Contracts....220 What does GSA do if it learns of unofficial use of a Government motor vehicle? GSA reports...

  10. Development and Testing of a Differential Absorption LIDAR system for Greenhouse Gas Measurements

    NASA Astrophysics Data System (ADS)

    Maxwell, S. E.; Douglass, K.; Plusquellic, D.; Whetstone, J. R.

    2013-12-01

    Our objective is to develop accurate and reliable methods for quantifying distributed carbon sources and sinks to support both mitigation efforts and climate change research. We will describe progress toward a field-deployable, eye-safe differential absorption LIDAR system. The current version of our system utilizes a high repetition rate (>200 kHz), 200 ns pulsed fiber amplifier driven by tunable DFB lasers around 1602 nm. Collection is performed using a small (3' diameter) telescope and an avalanche photodiode. We demonstrate a rapid hard target measurement of ambient levels of CO2 in our 100m test facility using low powers from the fiber laser and a highly-retro-reflecting target. We also discuss progress toward a range resolved measurement in the test facility, planned upgrades to the facility, and the development of a low-backscatter beam dump for range-limited applications.

  11. Vibration energy absorption in the whole-body system of a tractor operator.

    PubMed

    Szczepaniak, Jan; Tanaś, Wojciech; Kromulski, Jacek

    2014-01-01

    Many people are exposed to whole-body vibration (WBV) in their occupational lives, especially drivers of vehicles such as tractor and trucks. The main categories of effects from WBV are perception degraded comfort interference with activities-impaired health and occurrence of motion sickness. Absorbed power is defined as the power dissipated in a mechanical system as a result of an applied force. The vibration-induced injuries or disorders in a substructure of the human system are primarily associated with the vibration power absorption distributed in that substructure. The vibration power absorbed by the exposed body is a measure that combines both the vibration hazard and the biodynamic response of the body. The article presents measurement method for determining vibration power dissipated in the human whole body system called Vibration Energy Absorption (VEA). The vibration power is calculated from the real part of the force-velocity cross-spectrum. The absorbed power in the frequency domain can be obtained from the cross-spectrum of the force and velocity. In the context of the vibration energy transferred to a seated human body, the real component reflects the energy dissipated in the biological structure per unit of time, whereas the imaginary component reflects the energy stored/released by the system. The seated human is modeled as a series/parallel 4-DOF dynamic models. After introduction of the excitation, the response in particular segments of the model can be analyzed. As an example, the vibration power dissipated in an operator has been determined as a function of the agricultural combination operating speed 1.39 - 4.16 ms(-1). PMID:24959797

  12. Quantum cascade laser-based multipass absorption system for hydrogen peroxide detection

    NASA Astrophysics Data System (ADS)

    Cao, Yingchun; Sanchez, Nancy P.; Jiang, Wenzhe; Ren, Wei; Lewicki, Rafal; Jiang, Dongfang; Griffin, Robert J.; Tittel, Frank K.

    2015-01-01

    Hydrogen peroxide (H2O2) is a relevant molecular trace gas species, that is related to the oxidative capacity of the atmosphere, the production of radical species such as OH, the generation of sulfate aerosol via oxidation of S(IV) to S(VI), and the formation of acid rain. The detection of atmospheric H2O2 involves specific challenges due to its high reactivity and low concentration (ppbv to sub-ppbv level). Traditional methods for measuring atmospheric H2O2 concentration are often based on wet-chemistry methods that require a transfer from the gas- to liquid-phase for a subsequent determination by techniques such as fluorescence spectroscopy, which can lead to problems such as sampling artifacts and interference by other atmospheric constituents. A quartz-enhanced photoacoustic spectroscopy-based system for the measurement of atmospheric H2O2 with a detection limit of 75 ppb for 1-s integration time was previously reported. In this paper, an updated H2O2 detection system based on long-optical-path-length absorption spectroscopy by using a distributed feedback quantum cascade laser (DFB-QCL) will be described. A 7.73-μm CW-DFB-QCL and a thermoelectrically cooled infrared detector, optimized for a wavelength of 8 μm, are employed for theH2O2 sensor system. A commercial astigmatic Herriott multi-pass cell with an effective optical path-length of 76 m is utilized for the reported QCL multipass absorption system. Wavelength modulation spectroscopy (WMS) with second harmonic detection is used for enhancing the signal-to-noise-ratio. A minimum detection limit of 13.4 ppb is achieved with a 2 s sampling time. Based on an Allan-Werle deviation analysis the minimum detection limit can be improved to 1.5 ppb when using an averaging time of 300 s.

  13. Optimization of A 2-Micron Laser Frequency Stabilization System for a Double-Pulse CO2 Differential Absorption Lidar

    NASA Technical Reports Server (NTRS)

    Chen, Songsheng; Yu, Jirong; Bai, Yingsin; Koch, Grady; Petros, Mulugeta; Trieu, Bo; Petzar, Paul; Singh, Upendra N.; Kavaya, Michael J.; Beyon, Jeffrey

    2010-01-01

    A carbon dioxide (CO2) Differential Absorption Lidar (DIAL) for accurate CO2 concentration measurement requires a frequency locking system to achieve high frequency locking precision and stability. We describe the frequency locking system utilizing Frequency Modulation (FM), Phase Sensitive Detection (PSD), and Proportional Integration Derivative (PID) feedback servo loop, and report the optimization of the sensitivity of the system for the feed back loop based on the characteristics of a variable path-length CO2 gas cell. The CO2 gas cell is characterized with HITRAN database (2004). The method can be applied for any other frequency locking systems referring to gas absorption line.

  14. Realising a quantum absorption refrigerator with an atom-cavity system

    NASA Astrophysics Data System (ADS)

    Mitchison, Mark T.; Huber, Marcus; Prior, Javier; Woods, Mischa P.; Plenio, Martin B.

    2016-03-01

    An autonomous quantum thermal machine comprising a trapped atom or ion placed inside an optical cavity is proposed and analysed. Such a machine can operate as a heat engine whose working medium is the quantised atomic motion or as an absorption refrigerator that cools without any work input. Focusing on the refrigerator mode, we predict that it is possible with state-of-the-art technology to cool a trapped ion almost to its motional ground state using a thermal light source such as sunlight. We nonetheless find that a laser or a similar reference system is necessary to stabilise the cavity frequencies. Furthermore, we establish a direct and heretofore unacknowledged connection between the abstract theory of quantum absorption refrigerators and practical sideband cooling techniques. We also highlight and clarify some assumptions underlying several recent theoretical studies on self-contained quantum engines and refrigerators. Our work indicates that cavity quantum electrodynamics is a promising and versatile experimental platform for the study of autonomous thermal machines in the quantum domain.

  15. Highly efficient SO₂ absorption and its subsequent utilization by weak base/polyethylene glycol binary system.

    PubMed

    Yang, Zhen-Zhen; He, Liang-Nian; Zhao, Ya-Nan; Yu, Bing

    2013-02-01

    A binary system consisting of polyethylene glycol (PEG, proton donor)/PEG-functionalized base with suitable basicity was developed for efficient gas desulfurization (GDS) and can be regarded as an alternative approach to circumvent the energy penalty problem in the GDS process. High capacity for SO(2) capture up to 4.88 mol of SO(2)/mol of base was achieved even under low partial pressure of SO(2). Furthermore, SO(2) desorption runs smoothly under mild conditions (N(2), 25 °C) and no significant drop in SO(2) absorption was observed after five-successive absorption-desorption cycles. On the other hand, the absorbed SO(2) by PEG(150)MeIm/PEG(150), being considered as the activated form of SO(2), can be directly transformed into value-added chemicals under mild conditions, thus eliminating the energy penalty for SO(2) desorption and simultaneously realizing recycle of the absorbents. Thus, this SO(2) capture and utilization (SCU) process offers an alternative way for GDS and potentially enables the SO(2) conversion from flue gas to useful chemicals as a value-added process.

  16. THE PHYSICAL CONDITIONS OF THE INTRINSIC N V NARROW ABSORPTION LINE SYSTEMS OF THREE QUASARS

    SciTech Connect

    Wu Jian; Charlton, Jane C.; Misawa, Toru; Eracleous, Michael; Ganguly, Rajib E-mail: misawatr@shinshu-u.ac.j

    2010-10-20

    We employ detailed photoionization models to infer the physical conditions of intrinsic narrow absorption line systems found in high-resolution spectra of three quasars at z = 2.6-3.0. We focus on a family of intrinsic absorbers characterized by N V lines that are strong relative to the Ly{alpha} lines. The inferred physical conditions are similar for the three intrinsic N V absorbers, with metallicities greater than 10 times the solar value (assuming a solar abundance pattern), and with high ionization parameters (log U {approx} 0). Thus, we conclude that the unusual strength of the N V lines results from a combination of partial coverage, a high ionization state, and high metallicity. We consider whether dilution of the absorption lines by flux from the broad emission line region can lead us to overestimate the metallicities and we find that this is an unlikely possibility. The high abundances that we infer are not surprising in the context of scenarios in which metal enrichment takes place very early on in massive galaxies. We estimate that the mass outflow rate in the absorbing gas (which is likely to have a filamentary structure) is less than a few M{sub sun} yr{sup -1} under the most optimistic assumptions, although it may be embedded in a much hotter, more massive outflow.

  17. Particle extinction measured at ambient conditions with differential optical absorption spectroscopy. 1. system setup and characterization.

    PubMed

    Müller, Thomas; Müller, Detlef; Dubois, René

    2005-03-20

    We describe an instrument for measuring the particle extinction coefficient at ambient conditions in the spectral range from 270 to 1000 nm. It is based on a differential optical absorption spectroscopy (DOAS) system, which was originally used for measuring trace-gas concentrations of atmospheric absorbers in the ultraviolet-visible wavelength range. One obtains the particle extinction spectrum by measuring the total atmospheric extinction and subtracting trace-gas absorption and Rayleigh scattering. The instrument consists of two nested Newton-type telescopes, which are simultaneously used for emitting and detecting light, and two arrays of retroreflectors at the ends of the two light paths. The design of this new instrument solves crucial problems usually encountered in the design of such instruments. The telescope is actively repositioned during the measurement cycle. Particle extinction is simultaneously measured at several wavelengths by the use of two grating spectrometers. Optical turbulence causes lateral movement of the spot of light in the receiver telescope. Monitoring of the return signals with a diode permits correction for this effect. Phase-sensitive detection efficiently suppresses background signals from the atmosphere as well as from the instrument itself. The performance of the instrument was tested during a measurement period of 3 months from January to March 2000. The instrument ran without significant interruption during that period. A mean accuracy of 0.032 km(-1) was found for the extinction coefficient for an 11-day period in March. PMID:15813269

  18. Nature and statistical properties of quasar associated absorption systems in the XQ-100 Legacy Survey

    NASA Astrophysics Data System (ADS)

    Perrotta, S.; D'Odorico, V.; Prochaska, J. X.; Cristiani, S.; Cupani, G.; Ellison, S.; López, S.; Becker, G. D.; Berg, T. A. M.; Christensen, L.; Denney, K. D.; Hamann, F.; Pâris, I.; Vestergaard, M.; Worseck, G.

    2016-11-01

    We statistically study the physical properties of a sample of narrow absorption line (NAL) systems looking for empirical evidences to distinguish between intrinsic and intervening NALs without taking into account any a priori definition or velocity cut-off. We analyse the spectra of 100 quasars with 3.5 < zem < 4.5, observed with X-shooter/Very Large Telescope in the context of the XQ-100 Legacy Survey. We detect an ˜8σ excess in the C IV number density within 10 000 km s- 1 of the quasar emission redshift with respect to the random occurrence of NALs. This excess does not show a dependence on the quasar bolometric luminosity and it is not due to the redshift evolution of NALs. It extends far beyond the standard 5000 km s- 1 cut-off traditionally defined for associated absorption lines. We propose to modify this definition, extending the threshold to 10 000 km s- 1 when weak absorbers (equivalent width < 0.2 Å) are also considered. We infer N V is the ion that better traces the effects of the quasar ionization field, offering the best statistical tool to identify intrinsic systems. Following this criterion, we estimate that the fraction of quasars in our sample hosting an intrinsic NAL system is 33 per cent. Lastly, we compare the properties of the material along the quasar line of sight, derived from our sample, with results based on close quasar pairs investigating the transverse direction. We find a deficiency of cool gas (traced by C II) along the line of sight connected to the quasar host galaxy, in contrast with what is observed in the transverse direction.

  19. 41 CFR 102-3.100 - What are the responsibilities and functions of GSA?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... other administrative guidelines and management controls for advisory committees, and assists other... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What are the responsibilities and functions of GSA? 102-3.100 Section 102-3.100 Public Contracts and Property Management...

  20. 75 FR 1788 - General Services Administration Acquisition Regulation; Submission for OMB Review; GSA Form 1364...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-13

    ... From the Federal Register Online via the Government Publishing Office GENERAL SERVICES ADMINISTRATION General Services Administration Acquisition Regulation; Submission for OMB Review; GSA Form 1364...: Under the provisions of the Paperwork Reduction Act of 1995 (44 U.S.C. Chapter 35), the General...

  1. 41 CFR 102-118.435 - What procedures does GSA use to perform a postpayment audit?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Division has the delegated authority to implement the following procedures: (a) Audit selected TSP bills after payment; (b) Audit selected TSP bills before payment as needed to protect the Government's... Notice of Overcharge is prepared and mailed for each bill; and (g) Issue a GSA Notice of...

  2. 41 CFR 102-118.435 - What procedures does GSA use to perform a postpayment audit?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Division has the delegated authority to implement the following procedures: (a) Audit selected TSP bills after payment; (b) Audit selected TSP bills before payment as needed to protect the Government's... Notice of Overcharge is prepared and mailed for each bill; and (g) Issue a GSA Notice of...

  3. Gay-Straight Alliance (GSA) Members' Engagement with Sex Education in Canadian High Schools

    ERIC Educational Resources Information Center

    Lapointe, Alicia

    2014-01-01

    This paper offers an examination of gay-straight alliance (GSA) members' engagement with sex education, sexual health, and prejudice and discrimination in Canadian public high schools. It explores how five students' (four straight and one gay-identifying) participation in GSAs served as a springboard for learning about and challenging…

  4. 41 CFR 101-26.505-7 - GSA assistance in selection of furniture and furnishings.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true GSA assistance in selection of furniture and furnishings. 101-26.505-7 Section 101-26.505-7 Public Contracts and Property..., upon request, furnish agencies with information on the types, styles, finishes, coverings, and...

  5. 41 CFR 101-26.505-7 - GSA assistance in selection of furniture and furnishings.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true GSA assistance in selection of furniture and furnishings. 101-26.505-7 Section 101-26.505-7 Public Contracts and Property..., upon request, furnish agencies with information on the types, styles, finishes, coverings, and...

  6. GSA Advisors' Self-Efficacy Related to LGBT Youth of Color and Transgender Youth

    ERIC Educational Resources Information Center

    Poteat, V. Paul; Scheer, Jillian R.

    2016-01-01

    Gay-Straight Alliances (GSAs) serve lesbian, gay, bisexual, transgender (LGBT) and heterosexual youth from diverse backgrounds. Although some attention has been given to youth members in general, little attention has been given to adult advisors. Among 47 GSA advisors from 33 high schools (39 cisgender female, 8 cisgender male), the authors…

  7. 41 CFR 105-64.108 - How does GSA safeguard personal information?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... incorporate security controls such as password protection, verification of identity of authorized users... Services Administration 64-GSA PRIVACY ACT RULES 64.1-Policies and Responsibilities § 105-64.108 How does... physical safeguards to ensure the security and confidentiality of records, protect the records...

  8. 32 CFR 644.314 - Rules and regulations of the General Services Administration (GSA).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Rules and regulations of the General Services Administration (GSA). 644.314 Section 644.314 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal § 644.314 Rules and regulations...

  9. 32 CFR 644.314 - Rules and regulations of the General Services Administration (GSA).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Rules and regulations of the General Services Administration (GSA). 644.314 Section 644.314 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal § 644.314 Rules and regulations...

  10. 41 CFR 105-54.310 - Advisory committee duties of the GSA Committee Management Officer.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Committees. (c) Guidelines on committee management operations and procedures as maintained and updated; and... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Advisory committee duties of the GSA Committee Management Officer. 105-54.310 Section 105-54.310 Public Contracts...

  11. 41 CFR 102-117.350 - How will GSA use reports I submit?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... transportation related services will provide GSA with: (1) The ability to assess the magnitude and key characteristics of transportation within the Government (e.g., how much agencies spend; what type of commodity is... procedures to improve Government transportation; and (3) A better understanding of how your activity...

  12. 41 CFR 102-117.350 - How will GSA use reports I submit?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... transportation related services will provide GSA with: (1) The ability to assess the magnitude and key characteristics of transportation within the Government (e.g., how much agencies spend; what type of commodity is... procedures to improve Government transportation; and (3) A better understanding of how your activity...

  13. Interactions between angiotensin peptides and the sympathetic nervous system mediating intestinal sodium and water absorption in the rat.

    PubMed Central

    Levens, N R; Peach, M J; Carey, R M

    1981-01-01

    The purpose of this study was to determine the locus of interaction of angiotensin peptides with the sympathetic nervous system leading to alterations in jejunal sodium and water transport. At low physiological doses, angiotensin II (AII) stimulates jejunal sodium and water absorption, while at high doses peptide inhibits absorption and/or stimulates secretion. Both the stimulation of jejunal transport and the inhibition of absorption were expressed in adrenalectomized rats. However, the stimulation of jejunal water absorption was abolished and a potentiated inhibition of transport was expressed in peripherally sympathectomized rats (intact adrenal medulla) and in normal rats after administration of guanethadine, phentolamine, and prazosin. The angiotensin analog (Sar1 Leu8)-AII has low efficacy and is a potent competitive antagonist of the parent peptide in pressor and myotropic systems, but is a full agonist with even greater potency than AII in stimulating jejunal transport. The increased water transport in response to (Sar1 Leu8)-AII is not secondary to enhanced renal renin release, as the analog also stimulated jejunal transport in the presence of captopril and after bilateral nephrectomy. The stimulation of absorption in response to (Sar1 Leu8)-AII alone or together with AII was abolished by phentolamine. These data demonstrate that AII-increased intestinal absorption is secondary to the release of norepinephrine from nerve endings in the jejunum and that AII inhibition of absorption is not mediated by the sympathetic nervous system. The analog (Sar1 Leu8)-AII is a full agonist in the stimulation of jejunal transport (increased norepinephrine release), but antagonizes the inhibitory response to high doses of AII. Angiotensin peptides are potent modulators of intestinal sodium and water absorption. PMID:7204574

  14. Thermodynamic optimization of a solar system for cogeneration of water heating/purification and absorption cooling

    NASA Astrophysics Data System (ADS)

    Hovsapian, Zohrob O.

    This dissertation presents a contribution to understanding the behavior of solar powered air conditioning and refrigeration systems with a view to determining the manner in which refrigeration rate; mass flows, heat transfer areas, and internal architecture are related. A cogeneration system consisting of a solar concentrator, a cavity-type receiver, a gas burner, and a thermal storage reservoir is devised to simultaneously produce water heating/purification and cooling (absorption refrigerator system). A simplified mathematical model, which combines fundamental and empirical correlations, and principles of classical thermodynamics, mass and heat transfer, is developed. An experimental setup was built to adjust and validate the numerical results obtained with the mathematical model. The proposed model is then utilized to simulate numerically the system transient and steady state response under different operating and design conditions. A system global optimization for maximum performance (or minimum exergy destruction) in the search for minimum pull-down and pull-up times, and maximum system second law efficiency is performed with low computational time. Appropriate dimensionless groups are identified and the results presented in normalized charts for general application. The numerical results show that the three way maximized system second law efficiency, etaII,max,max,max, occurs when three system characteristic mass flow rates are optimally selected in general terms as dimensionless heat capacity rates, i.e., (Psisps , Psiwxwx, PsiHs)opt ≅ (1.43, 0.17, 0.19). The minimum pull-down and pull-up times, and maximum second law efficiencies found with respect to the optimized operating parameters are sharp and, therefore important to be considered in actual design. As a result, the model is expected to be a useful tool for simulation, design, and optimization of solar energy systems in the context of distributed power generation.

  15. A novel control system for automatically locking a diode laser frequency to a selected gas absorption line

    NASA Astrophysics Data System (ADS)

    Dong, Lei; Yin, Wangbao; Ma, Weiguang; Jia, Suotang

    2007-05-01

    A novel control system has been developed for avoiding manual operation during traditional frequency locking. The control system uses a computer with a commercial data acquisition card. This accomplishes the whole operation of frequency locking, including generating ramp, searching locking point, engaging a proportional-integral-differential (PID) regulator at the proper time and outputting PID compensation signal. Moreover, a new method has also been employed to make the novel control system accurately identify the locking points of all absorption lines within the scanning range, so that the laser frequency can be automatically firmly brought onto any selected absorption line centre without any adjusting time. The operation of the system, the ability to identify absorption lines and the performance of the frequency locking were discussed in detail. Successful tests were made with two different lasers: external cavity diode lasers and distributed feedback diode lasers.

  16. Method for Direct Measurement of Cosmic Acceleration by 21-cm Absorption Systems

    NASA Astrophysics Data System (ADS)

    Yu, Hao-Ran; Zhang, Tong-Jie; Pen, Ue-Li

    2014-07-01

    So far there is only indirect evidence that the Universe is undergoing an accelerated expansion. The evidence for cosmic acceleration is based on the observation of different objects at different distances and requires invoking the Copernican cosmological principle and Einstein's equations of motion. We examine the direct observability using recession velocity drifts (Sandage-Loeb effect) of 21-cm hydrogen absorption systems in upcoming radio surveys. This measures the change in velocity of the same objects separated by a time interval and is a model-independent measure of acceleration. We forecast that for a CHIME-like survey with a decade time span, we can detect the acceleration of a ΛCDM universe with 5σ confidence. This acceleration test requires modest data analysis and storage changes from the normal processing and cannot be recovered retroactively.

  17. A computer model for simulation of absorption systems in flexible and modular form

    SciTech Connect

    Grossman, G; Gommed, K; Gadoth, D

    1991-08-01

    A computer code in a flexible and modular form developed for simulation of absorption systems makes it possible to investigate various cycle configurations with different working fluids. The code is based on unit subroutines containing the governing equations for the system's components. The equations are linked by a main program according to the user's specifications to form the complete system. The equations are solved simultaneously, and fluid properties are taken from a property data base. The code is user oriented and requires a relatively simple input containing the given operating conditions and the working fluid at each state point. The user conveys to the computer an image of his or her cycle by specifying the different subunits and their interconnection. Based on this information, the program calculates (1) the temperature, flow rate, concentration, pressure, and vapor fraction at each state point in the system and (2) the heat duty at each unit, from which the coefficient of performance may be determined. The program has been used successfully to simulate a variety of single-stage, double-stage, and dual-loop heat pumps and heat transformers, with the working fluids LiBr-H{sup 2}O,H{sub 2}O-NH{sub 3}, LiBr/H{sub 2}O-NH{sub 3}, LiBr/ZnBr{sub 2}-CH{sub 3}OH, and more. 23 refs., 10 figs., 13 tabs.

  18. Broadband near total light absorption in non-PT-symmetric waveguide-cavity systems.

    PubMed

    Huang, Yin; Min, Changjun; Veronis, Georgios

    2016-09-19

    We introduce broadband waveguide absorbers with near unity absorption. More specifically, we propose a compact non-parity-time-symmetric perfect absorber unit cell, consisting of two metal-dielectric-metal (MDM) stub resonators with unbalanced gain and loss side-coupled to a MDM waveguide, based on unidirectional reflectionlessness at exceptional points. With proper design, light can transport through the perfect absorber unit cell with reflection close to zero in a broad wavelength range. By cascading multiple unit cell structures, the overall absorption spectra are essentially the superposition of the absorption spectra of the individual perfect absorber unit cells, and absorption of ~ 100% is supported in a wide range of frequencies.

  19. Local chemical potentials and pressures in heterogeneous systems: Adsorptive, absorptive, interfaces

    NASA Astrophysics Data System (ADS)

    Tovbin, Yu. K.

    2016-07-01

    Equations self-consistently describing chemical and mechanical equilibria in heterogeneous systems are derived. The equations are based on the lattice gas model using discrete distributions of molecules in space (on a scale comparable to molecular size) and continuum distributions of molecules (at short distances inside the cells) during their translational and vibrational motions. It is shown that the theory provides a unified description of the equilibrium distributions of molecules in three aggregate states and at their interfaces. Potential functions of intermolecular interactions (such as Mie pair potentials) in several coordination spheres that determine the compressibility of the lattice structure are considered. For simplicity, it is assumed that differences between the sizes of mixture components are small. Expressions for the local components of the pressure tensor inside multicomponent solid phases and heterogeneous systems (adsorptive, absorptive, and interfaces) are obtained. It is established that they can be used to calculate the lattice parameters of deforming phases and the thermodynamic characteristics of interfaces, including surface tension. The tensor nature of the chemical potential in heterogeneous systems is discussed.

  20. Advanced Sine Wave Modulation of Continuous Wave Laser System for Atmospheric CO2 Differential Absorption Measurements

    NASA Technical Reports Server (NTRS)

    Campbell, Joel F.; Lin, Bing; Nehrir, Amin R.

    2014-01-01

    NASA Langley Research Center in collaboration with ITT Exelis have been experimenting with Continuous Wave (CW) laser absorption spectrometer (LAS) as a means of performing atmospheric CO2 column measurements from space to support the Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) mission.Because range resolving Intensity Modulated (IM) CW lidar techniques presented here rely on matched filter correlations, autocorrelation properties without side lobes or other artifacts are highly desirable since the autocorrelation function is critical for the measurements of lidar return powers, laser path lengths, and CO2 column amounts. In this paper modulation techniques are investigated that improve autocorrelation properties. The modulation techniques investigated in this paper include sine waves modulated by maximum length (ML) sequences in various hardware configurations. A CW lidar system using sine waves modulated by ML pseudo random noise codes is described, which uses a time shifting approach to separate channels and make multiple, simultaneous online/offline differential absorption measurements. Unlike the pure ML sequence, this technique is useful in hardware that is band pass filtered as the IM sine wave carrier shifts the main power band. Both amplitude and Phase Shift Keying (PSK) modulated IM carriers are investigated that exibit perfect autocorrelation properties down to one cycle per code bit. In addition, a method is presented to bandwidth limit the ML sequence based on a Gaussian filter implemented in terms of Jacobi theta functions that does not seriously degrade the resolution or introduce side lobes as a means of reducing aliasing and IM carrier bandwidth.

  1. A population pharmacokinetic model for the complex systemic absorption of ropivacaine after femoral nerve block in patients undergoing knee surgery.

    PubMed

    Gaudreault, François; Drolet, Pierre; Fallaha, Michel; Varin, France

    2012-12-01

    Because of its slow systemic absorption and flip-flop kinetics, ropivacaine's pharmacokinetics after a peripheral nerve block has never been thoroughly characterized. The purpose of this study was to develop a population pharmacokinetic model for ropivacaine after loco-regional administration and to identify patient characteristics that may influence the drug's absorption and disposition. Frequent plasma samples were taken up to 93 h after a 100 mg dose given as femoral block for postoperative analgesia in 15 orthopedic patients. Ropivacaine plasma concentration-time data were analyzed using a nonlinear mixed effects modeling method. A one-compartment model with parallel inverse Gaussian and time-dependent inputs best described ropivacaine plasma concentration-time curves. Ropivacaine systemic absorption was characterized by a rapid phase (mean absorption time of 25 ± 4.8 min) followed by a much slower phase (half-life of 3.9 ± 0.65 h). Interindividual variability (IIV) for these parameters, 58 and 9 %, indicated that the initial absorption phase was more variable. The apparent volume of distribution (V/F = 77.2 ± 11.5 L, IIV = 26 %) was influenced by body weight (Δ 1.49 % per kg change) whereas the absorption rate constant (slower phase) of ropivacaine was affected by age (Δ 2.25 % per year change). No covariate effects were identified for the apparent clearance of the drug (CL/F =10.8 ± 1.0 L/h, 34  IIV = 34 %). These findings support our hypothesis that modeling a complex systemic absorption directly from plasma concentration-time curves exhibiting flip-flop kinetics is possible. Only the age-effect was considered as relevant for possible dosing adjustments.

  2. A search for ultraviolet circumstellar gas absorption features in alpha Piscis Austrinus (Fomalhaut), a possible Beta Pictoris-like system

    NASA Technical Reports Server (NTRS)

    Cheng, K.-P.; Bruhweiler, Fred C.; Kondo, Yoji

    1994-01-01

    Archival high-dispersion International Ultraviolet Explorer (IUE) spectra have been used to search for circumstellar gas absorption features in alpha PsA (A3 V), a nearby (6.7 pc) proto-planetary system candidate. Recent sub-millimeter mapping observations around the region of alpha PsA indicate a spatially resolved dust disk like the one seen around Beta Pic. To determine how closely this putative disk resembles that of Beta Pic, we have searched for signatures of circumstellar gaseous absorption in all the available IUE high-dispersion data of alpha PsA. Examination of co-added IUE spectra shows weak circumstellar absorptions from excited levels in the resonance multiplet of Fe II near 2600 A. We also conclude that the sharp C I feature near 1657 A, previously identified as interstellar absorption toward alpha PsA, likely has a circumstellar origin. However, because the weakness of these absorption features, we will consider the presence of circumstellar gas as tentative and should be verified by using the Goddard High-Resolution Spectrograph aboard the Hubble Space Telescope. No corresponding circumstellar absorption is detected in higher ionization Fe III and Al III. Since the collisionally ionized nonphotospheric Al III resonance absorption seen in Beta Pic is likely formed close to the stellar surface, its absence in the UV spectra of alpha PsA could imply that, in contrast with Beta Pic, there is no active gaseous disk infall onto the central star. In the alpha PsA gaseous disk, if we assume a solar abundance for iron and all the iron is in the form of Fe II, plus a disk temperature of 5000 K, the Fe II UV1 absorption at 2611.8743 A infers a total hydrogen column density along the line of sight through the circumstellar disk of N(H) approximately equals 3.8 x 10(exp 17)/cm.

  3. Phase-dependent high refractive index without absorption in a four-level inverted-Y atomic system

    SciTech Connect

    Zhi-Qiang Zeng; Fu-Ti Liu; Yu-Ping Wang; Zeng-Hui Gao

    2015-01-31

    We consider a closed four-level inverted-Y system in the presence and the absence of a microwave field. It is found that due to the quantum coherence between the two lower levels, either induced by the spontaneous decay or by the microwave field, the refraction – absorption properties of the system can be modulated by controlling the relative phase of the applied fields in both driven ways. In particular, by properly setting the values of the relative phase, the desirable high index of refraction without absorption can be achieved. (nonlinear optical phenomena)

  4. COMPONENTS OF LASER SYSTEMS AND STABILITY PROBLEMS: Residual infrared absorption in metal mirrors

    NASA Astrophysics Data System (ADS)

    Vinogradov, Aleksandr V.; Tolstikhin, O. I.

    1988-08-01

    An analysis is made of the physical factors that limit the reflectivity of mirrors in the infrared range. It is shown that the mechanism responsible for the finite residual absorption is the electron-phonon interaction in the presence of a photon (Holstein-Gurzhi effect). A study is also made of the influence of the surface roughness on the absorptivity of mirrors.

  5. A multi-channel monolithic Ge detector system for fluorescence x-ray absorption spectroscopy

    SciTech Connect

    Bucher, J.J.; Allen, P.G.; Edelstein, N.M.; Shuh, D.K.; Madden, N.W.; Cork, C.; Luke, P.; Pehl, D.; Malone, D.

    1995-03-01

    Construction and performance of a monolithic quad-pixel Ge detector for fluorescence x-ray absorption spectroscopy (XAS) at synchrotron radiation sources are described. The detector semiconductor element has an active surface area of 4.0 cm{sup 2} which is electrically separated into four 1.0 cm{sup 2} pixels, with little interfacial dead volume. Spatial response of the array shows that cross-talk between adjacent pixels is < 10% for 5.9 keV photons that fall within 0.5 mm of the pixel boundaries. The detector electronics system uses pre-amplifiers built at LBNL with commercial Tennelec Model TC 244 amplifiers. Using an {sup 55}Fe test source (MnK{sub {alpha}}, 5.9 keV), energy resolution of better than 200 eV is achieved with a 4 {mu}sec peaking time. At 0.5 {mu}sec peaking time, pulse pileup results in a 75% throughput efficiency for an incoming count rate of 100 kHz. Initial XAS fluoresncece measurements at the beamline 4 wiggler end stations at SSRL show that the detector system has several advantages over commercial x-ray spectrometers for low-concentration counting.

  6. Nonlinear absorption and photoluminescence emission in nanocomposite films of Fuchsine Basic dye-polymer system

    NASA Astrophysics Data System (ADS)

    Sreekumar, G.; Louie Frobel, P. G.; Sreeja, S.; Suresh, S. R.; Mayadevi, S.; Muneera, C. I.; Suchand Sandeep, C. S.; Philip, Reji; Mukharjee, Chandrachur

    2011-04-01

    Fuchsine Basic dye-polyvinyl alcohol composite films were fabricated and their structure, nonlinear absorption as well as linear absorption and photoluminescence properties were investigated. Switchover from saturable absorption to two-photon assisted excited state absorption with increase in intensity was observed in the open aperture Z-scan study (Nd:YAG, 532 nm, 7 ns). The effective two-photon absorption coefficient β was found to be several orders higher than that reported for rhodamine B. The dye-polymer films were characterized as nanocomposites with dye microdomains encapsulated between molecules of the amorphous polymer and having average surface roughness as low as ≈0.46 nm. The samples also exhibited intense photoluminescence emission when excited with 534 nm radiation.

  7. Method of analyzing multiple sample simultaneously by detecting absorption and systems for use in such a method

    DOEpatents

    Yeung, Edward S.; Gong, Xiaoyi

    2004-09-07

    The present invention provides a method of analyzing multiple samples simultaneously by absorption detection. The method comprises: (i) providing a planar array of multiple containers, each of which contains a sample comprising at least one absorbing species, (ii) irradiating the planar array of multiple containers with a light source and (iii) detecting absorption of light with a detetion means that is in line with the light source at a distance of at leaat about 10 times a cross-sectional distance of a container in the planar array of multiple containers. The absorption of light by a sample indicates the presence of an absorbing species in it. The method can further comprise: (iv) measuring the amount of absorption of light detected in (iii) indicating the amount of the absorbing species in the sample. Also provided by the present invention is a system for use in the abov metho.The system comprises; (i) a light source comrnpising or consisting essentially of at leaat one wavelength of light, the absorption of which is to be detected, (ii) a planar array of multiple containers, and (iii) a detection means that is in line with the light source and is positioned in line with and parallel to the planar array of multiple contiainers at a distance of at least about 10 times a cross-sectional distance of a container.

  8. 41 CFR 102-41.30 - What is GSA's role in the disposition of property covered by this part?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the United States, it may be returned to the claimant. (b) Forfeited, voluntarily abandoned, or... seizing agency files a request for the property for its official use, the GSA Region 3/National...

  9. 41 CFR 102-41.140 - When do we report to GSA unclaimed personal property not retained for official use?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... has filed a claim for it, the title to the property vests in the Government. If you decide not to retain the property for official use, report it as excess to GSA in accordance with part 102-36 of...

  10. Saturable and Reverse Saturable Absorption in Nanocomposite Films of Naphthol Green B Dye-polymer System

    NASA Astrophysics Data System (ADS)

    Devi, S. Maya; Sreeja, S.; Frobel, P. G. Louie; Suresh, S. R.; Muneera, C. I.

    2011-10-01

    Naphthol Green B dye-polyvinyl alcohol composite films were fabricated and their nonlinear absorption properties were investigated using the Z-scan technique under excitation with 5ns laser light pulses at 532 nm. The samples displayed a switchover from saturable absorption to reverse saturable absorption with increase in either intensity or concentration. The measured values of β and IS were found to be of the order of 10-7 cm/W and 109 W/cm2 respectively. The atomic force microscopic analysis of the composite films revealed homogeneous distribution of aggregated nanoclusters marked by a low average surface roughness ≈1.8 nm.

  11. Effects of absorption on high-latitude meteor scatter communication systems

    SciTech Connect

    Ostergaard, J.C.; Weitzen, J.A.; Kossey, P.A.; Bailey, A.D.; Bench, P.M. USAF, Geophysics Laboratory, Hanscom AFB, MA )

    1991-08-01

    Propagation data covering the solar disturbances of March and August 1989, acquired with the Geophysical Laboratory's High-Latitude Meteor Scatter Test-Bed, are presented and are examined as a function of frequency. It was found that the two solar-disturbance events were very different. The August event was dominated by ionospheric absorption which affected meteor arrival rates and duty cycles primarily at 35 and 45 MHz, while the March event combined weak ionospheric absorption with large solar noise burst. The absorption was frequency dependent during both events. 21 refs.

  12. Germanium determination by flame atomic absorption spectrometry: an increased vapor pressure-chloride generation system.

    PubMed

    Kaya, Murat; Volkan, Mürvet

    2011-03-15

    A new chloride generation system was designed for the direct, sensitive, rapid and accurate determination of the total germanium in complex matrices. It was aimed to improve the detection limit of chloride generation technique by increasing the vapor pressure of germanium tetrachloride (GeCl(4)). In order to do so, a novel joint vapor production and gas-liquid separation unit equipped with a home-made oven was incorporated to an ordinary nitrous oxide-acetylene flame atomic absorption spectrometer. Several variables such as reaction time, temperature and acid concentration have been investigated. The linear range for germanium determination was 0.1-10 ng mL(-1) for 1 mL sampling volume with a detection limit (3s) of 0.01 ng mL(-1). The relative standard deviation (RSD) was 2.4% for nine replicates of a 1 ng mL(-1) germanium solution. The method was validated by the analysis of one non-certified and two certified geochemical reference materials, respectively, CRM GSJ-JR-2 (Rhyolite), and GSJ-JR-1 (Rhyolite), and GBW 07107 (Chinese Rock). Selectivity of the method was investigated for Cd(2+), Co(2+), Cu(2+), Fe(3+), Ga(3+), Hg(2+), Ni(2+), Pb(2+), Sn(2+), and Zn(2+) ions and ionic species of As(III), Sb(III), Te(IV), and Se(IV). PMID:21315908

  13. Two-photon absorption cross section measurement in the gamma band system of nitric oxide

    SciTech Connect

    Burris, J.F. Jr.

    1982-01-01

    A dye laser with a single longitudinal mode and very stable spatial mode structure has been constructed. With this laser system a four-wave mixing experiment was done in the gamma bands of nitric oxide using two photon resonance. Another four-wave mixing experiment was done in nitrogen using coherent anti-Stokes Raman scattering (CARS) and the two signals ratioed. Using accurately known values of the Raman scattering cross section, the third order susceptibility in NO was determined without needing to know the spatial and temporal properties of the dye lasers. From this susceptibility, the two photon absorption cross section was calculated with the explicit dependence of sigma/sup (2)/ upon X/sup (3)/ shown. For the R/sub 22/ + S/sub 12/(J'' = 9 1/2) (A/sup 2/..sigma..+(v' = 0) -- X/sup 2/..pi..(v'' = 0)) line, sigma/sup (2)/ = (1.0 +/- 0.6) x 10/sup -38/cm/sup 4/g(2/sub 1/-Vertical Barsub f/ is the normalized lineshape. Branching ratios for the A/sup 2/..sigma..+(v' = n) ..-->.. X/sup 2/..omega..(v'' = n)(n = o,...9) transitions of NO were also measured, Franck-Condon factors calculated and the lifetime of the A state determined.

  14. Germanium determination by flame atomic absorption spectrometry: an increased vapor pressure-chloride generation system.

    PubMed

    Kaya, Murat; Volkan, Mürvet

    2011-03-15

    A new chloride generation system was designed for the direct, sensitive, rapid and accurate determination of the total germanium in complex matrices. It was aimed to improve the detection limit of chloride generation technique by increasing the vapor pressure of germanium tetrachloride (GeCl(4)). In order to do so, a novel joint vapor production and gas-liquid separation unit equipped with a home-made oven was incorporated to an ordinary nitrous oxide-acetylene flame atomic absorption spectrometer. Several variables such as reaction time, temperature and acid concentration have been investigated. The linear range for germanium determination was 0.1-10 ng mL(-1) for 1 mL sampling volume with a detection limit (3s) of 0.01 ng mL(-1). The relative standard deviation (RSD) was 2.4% for nine replicates of a 1 ng mL(-1) germanium solution. The method was validated by the analysis of one non-certified and two certified geochemical reference materials, respectively, CRM GSJ-JR-2 (Rhyolite), and GSJ-JR-1 (Rhyolite), and GBW 07107 (Chinese Rock). Selectivity of the method was investigated for Cd(2+), Co(2+), Cu(2+), Fe(3+), Ga(3+), Hg(2+), Ni(2+), Pb(2+), Sn(2+), and Zn(2+) ions and ionic species of As(III), Sb(III), Te(IV), and Se(IV).

  15. OBSERVING THE END OF COLD FLOW ACCRETION USING HALO ABSORPTION SYSTEMS

    SciTech Connect

    Stewart, Kyle R.; Kaufmann, Tobias; Bullock, James S.; Barton, Elizabeth J.; Maller, Ariyeh H.; Diemand, Juerg; Wadsley, James

    2011-07-01

    We use cosmological smoothed particle hydrodynamic simulations to study the cool, accreted gas in two Milky Way size galaxies through cosmic time to z = 0. We find that gas from mergers and cold flow accretion results in significant amounts of cool gas in galaxy halos. This cool circum-galactic component drops precipitously once the galaxies cross the critical mass to form stable shocks, M{sub vir} = M{sub sh} {approx} 10{sup 12} M{sub sun}. Before reaching M{sub sh}, the galaxies experience cold mode accretion (T < 10{sup 5} K) and show moderately high covering fractions in accreted gas: f{sub c} {approx} 30%-50% for R < 50 comoving kpc and N{sub Hi}>10{sup 16} cm{sup -2}. These values are considerably lower than observed covering fractions, suggesting that outflowing gas (not included here) is important in simulating galaxies with realistic gaseous halos. Within {approx}500 Myr of crossing the M{sub sh} threshold, each galaxy transitions to hot mode gas accretion, and f{sub c} drops to {approx}5%. The sharp transition in covering fraction is primarily a function of halo mass, not redshift. This signature should be detectable in absorption system studies that target galaxies of varying host mass, and may provide a direct observational tracer of the transition from cold flow accretion to hot mode accretion in galaxies.

  16. Theory of the electronic states and absorption spectrum of the LiCl:Ag+ impurity system

    NASA Astrophysics Data System (ADS)

    Jackson, Koblar A.; Lin, Chun C.

    1990-01-01

    The impurity absorption spectra of Ag+ and Cu+ impurities in alkali halide hosts show characteristically different features, despite the similar nature of the corresponding free ions. We use the self-interaction-corrected local-spin-density (SIC-LSD) theory to calculate the electronic structure of the ground state (4d) and the 5s and 5p excited states of the LiCl:Ag+ impurity ion. The method of linear combinations of atomic orbitals is used to determine the wave functions and energy levels. By comparing with previous calculations for LiCl:Cu+, we are able to attribute the differences in the d-->s and d-->p transitions in the ultraviolet spectra of these systems to the increased bonding between host crystal and impurity orbitals in LiCl:Ag+, due to the more extensive nature of the Ag+ 4d orbitals. A modification of the earlier SIC-LSD impurity-crystal procedure is introduced to treat the strongly mixed impurity states.

  17. Hydrogeologic implications of increased septic-tank-soil-absorption system density, Ogden Valley, Weber County, Utah

    USGS Publications Warehouse

    Lowe, Mike; Miner, Michael L.

    1990-01-01

    Ground water in Ogden Valley occurs in perched, confined, and unconfined aquifers in the valley fill to depths of 600 feet and more. The confined aquifer, which underlies only the western portion of the valley, is overlain by cleyey silt lacustrine sediments probably deposited during the Bonneville Basin's Little Valley lake cycle sometime between 90,000 and 150,000 years ago. The top of this cleyey silt confining layer is generally 25 to 60 feet below the ground surface. Unconfined conditions occur above and beyond the outer margin of the confining layer. The sediments overlying the confining layer are primarily Lake Bonneville deposits. Water samples from springs, streams, and wells around Pineview Reservoir, and from the reservoir itself, were collected and analyzed. These samples indicate that water quality in Ogden Valley is presently good. Average nitrate concentrations in the shallow unconfined aquifer increase toward the center of Ogden Valley. This trend was not observed in the confined aquifer. There is no evidence, however, of significant water-quality deterioration, even in the vicinity of Huntsville, a town that has been densely developed using septic-tank-soil-absorption systems for much of the time since it was founded in 1860.

  18. Clean Coal Technology III (CCT III) 10 MW demonstration of gas suspension absorption

    SciTech Connect

    Not Available

    1992-02-07

    The Gas Suspension Absorber (GSA) system brings coal combustion gases into contact with a suspended mixture of solids, including sulfur-absorbing lime. After the lime absorbs the sulfur pollutants, the solids are separated from the gases in a cyclone device and recirculated back into the system where they capture additional sulfur pollutant. The cleaned flue gases are sent through a dust collector before being released into the atmosphere. The key to the system's superior economic performance with high sulfur coals is the recirculation of solids. Typically, a solid particle will pass through the system about one hundred times before leaving the system. Another advantage of the GSA system is that a single spray nozzle is used to inject fresh lime slurry. The GSA system is expected to be the answer to the need of the US industry for an effective, economic and space efficient solution to the SO{sub 2} pollution problem.

  19. GSA's Green Proving Ground: Identifying, Testing and Evaluating Innovative Technologies; Preprint

    SciTech Connect

    Kandt, A.; Lowell, M.

    2012-05-01

    This paper will provide an overview of the GPG program and its objectives as well as a summary and status update of the 16 technologies selected for enhanced testing and evaluation in 2011. The federal government's General Services Administration's (GSA) Public Buildings Service (PBS) acquires space on behalf of the federal government through new construction and leasing, and acts as a caretaker for federal properties across the country. PBS owns or leases 9,624 assets and maintains an inventory of more than 370.2 million square feet of workspace, and as such has enormous potential for implementing energy efficient and renewable energy technologies to reduce energy and water use and associated emissions. The Green Proving Ground (GPG) program utilizes GSA's real estate portfolio to test and evaluate innovative and underutilized sustainable building technologies and practices. Findings are used to support the development of GSA performance specifications and inform decision making within GSA, other federal agencies, and the real estate industry. The program aims to drive innovation in environmental performance in federal buildings and help lead market transformation through deployment of new technologies. In 2011, the GPG program selected 16 technologies or practices for rigorous testing and evaluation. Evaluations are currently being performed in collaboration with the Department of Energy's National Laboratories, and a steady stream of results will be forthcoming throughout 2012. This paper will provide an overview of the GPG program and its objectives as well as a summary and status update of the 16 technologies selected for enhanced testing and evaluation in 2011. Lastly, it provides a general overview of the 2012 program.

  20. Aspinall Courthouse: GSA's Historic Preservation and Net-Zero Renovation Case Study

    SciTech Connect

    Chang, R.; Hayter, S.; Hotchkiss, E.; Pless, S.; Sielcken, J.; Smith-Larney, C.

    2014-10-01

    The federal government is mandated with improving efficiency of buildings, incorporating renewable energy, and achieving net-zero energy operations where possible. These challenges led GSA to consider aligning historic preservation renovations with net-zero energy goals. The Wayne N. Aspinall Federal Building and U.S. Courthouse (Aspinall Courthouse), in Grand Junction, Colorado, is an example of a renovation project that aimed to accomplish both historic preservation and net-zero energy goals.

  1. Low-Dimensional Water on Ru(0001); Model System for X-ray Absorption Spectroscopy Studies of Liquid Water

    SciTech Connect

    Nordlund, D.; Ogasawara, H.; Andersson, K.J.; Tatarkhanov, M.; Salmeron, M.; Pettersson, L. G. M.; Nilsson, A.

    2009-05-11

    We present an x-ray absorption spectroscopy results for fully broken to a complete H-bond network of water molecules on Ru(0001) by varying the morphology from isolated water molecules via two-dimensional clusters to a fully covered monolayer as probed by scanning tunneling microscopy. The sensitivity of x-ray absorption to the symmetry of H-bonding is further elucidated for the amino (-NH{sub 2}) group in glycine adsorbed on Cu(110) where the E-vector is parallel either to the NH donating an H-bond or to the non-H-bonded NH. The results give further evidence for the interpretation of the various spectral features of liquid water and for the general applicability of x-ray absorption spectroscopy to analyze H-bonded systems.

  2. Low-Dimensional Water on Ru(0001)Model System for X-ray Absorption Spectroscopy Studies of Liquid Water

    SciTech Connect

    Nordlund, D

    2012-02-14

    We present an x-ray absorption spectroscopy results for fully broken to a complete H-bond network of water molecules on Ru(0001) by varying the morphology from isolated water molecules via two-dimensional clusters to a fully covered monolayer as probed by scanning tunneling microscopy. The sensitivity of x-ray absorption to the symmetry of H-bonding is further elucidated for the amino (-NH{sub 2}) group in glycine adsorbed on Cu(110) where the E-vector is parallel either to the NH donating an H-bond or to the non-H-bonded NH. The results give further evidence for the interpretation of the various spectral features of liquid water and for the general applicability of x-ray absorption spectroscopy to analyze H-bonded systems.

  3. Broadband near total light absorption in non-PT-symmetric waveguide-cavity systems.

    PubMed

    Huang, Yin; Min, Changjun; Veronis, Georgios

    2016-09-19

    We introduce broadband waveguide absorbers with near unity absorption. More specifically, we propose a compact non-parity-time-symmetric perfect absorber unit cell, consisting of two metal-dielectric-metal (MDM) stub resonators with unbalanced gain and loss side-coupled to a MDM waveguide, based on unidirectional reflectionlessness at exceptional points. With proper design, light can transport through the perfect absorber unit cell with reflection close to zero in a broad wavelength range. By cascading multiple unit cell structures, the overall absorption spectra are essentially the superposition of the absorption spectra of the individual perfect absorber unit cells, and absorption of ~ 100% is supported in a wide range of frequencies. PMID:27661956

  4. The origin of the excess transit absorption in the HD 189733 system: planet or star?

    NASA Astrophysics Data System (ADS)

    Barnes, J. R.; Haswell, C. A.; Staab, D.; Anglada-Escudé, G.

    2016-10-01

    We have detected excess absorption in the emission cores of Ca II H&K during transits of HD 189733b for the first time. Using observations of three transits, we investigate the origin of the absorption, which is also seen in Hα and the Na I D lines. Applying differential spectrophotometry methods to the Ca II H and Ca II K lines combined, using respective passband widths of Δλ = 0.4 and 0.6 Å yields excess absorption of td = 0.0074 ± 0.0044 (1.7σ; Transit 1) and 0.0214 ± 0.0022 (9.8σ; Transit 2). Similarly, we detect excess Hα absorption in a passband of width Δλ = 0.7 Å, with td = 0.0084 ± 0.0016 (5.2σ) and 0.0121 ± 0.0012 (9.9σ). For both lines, Transit 2 is thus significantly deeper. Combining all three transits for the Na I D lines yields excess absorption of td = 0.0041 ± 0.0006 (6.5σ). By considering the time series observations of each line, we find that the excess apparent absorption is best recovered in the stellar reference frame. These findings lead us to postulate that the main contribution to the excess transit absorption in the differential light curves arises because the normalizing continuum bands form in the photosphere, whereas the line cores contain a chromospheric component. We cannot rule out that part of the excess absorption signature arises from the planetary atmosphere, but we present evidence which casts doubt on recent claims to have detected wind motions in the planet's atmosphere in these data.

  5. Simple system for measuring tritium Ad/absorption using a 2. pi. counter and thermal desorption spectrometer

    SciTech Connect

    Miyake, H.; Matsuyama, M.; Watanabe, K. ); Cowgill, D.F. )

    1992-03-01

    In this paper, the authors develop a simple system using tritium tracer and thermal desorption techniques to measure the tritium adsorption and/or absorption on/in a material having typical surface conditions: namely, not cleaned surface. The tritium counting devices used were a 2{pi} counter and conventional proportional counter. With this system, the amounts of ad/absorption could be measured without exposing the samples to air after exposing them to tritium gas. The overall efficiency (F) of the 2{pi} counter was described at F = exp({minus}2.64h), where h is the distance from the sample to the detector. Ad/absorption measurements were carried out for several materials used for fabricating conventional vacuum systems. The results were, in the order of decreasing amounts of ad/absorption, as (fiber reinforced plastics(FRP)) {gt} (nickel(Ni), molybdenum disulfide(MoS{sub 2})) {gt} (stainless steel (SS304), iron(Fe), aluminum alloy(A2219)) {gt} (boron nitride(h-BN), silicon carbide (SiC), SS304 passivated by anodic oxidation layers(ASS) and that by boron nitride segregation layers (BSS)). The relative amounts were abut 100 for Ni and 0.1 for ASS and BSS, being normalized to Fe = 1.

  6. Increased systemic exposure to rhizoma coptidis alkaloids in lipopolysaccharide-pretreated rats attributable to enhanced intestinal absorption.

    PubMed

    Ma, Bing-Liang; Yao, Meng-Kan; Zhong, Jie; Ma, Yue-Ming; Gao, Cheng-Lu; Wu, Jia-Sheng; Qiu, Fu-Rong; Wang, Chang-Hong; Wang, Xin-Hong

    2012-02-01

    Rhizoma coptidis is a rhizome commonly used in traditional Chinese medicine. After oral administration of rhizoma coptidis extract, the plasma concentrations of its effective alkaloid constituents are so low that their systemic therapeutic actions cannot be explained. This study aimed to investigate the influence of lipopolysaccharide (LPS) on the pharmacokinetics of the rhizoma coptidis alkaloids. Pharmacokinetic experiments were performed with rats; both in vitro absorption and efflux experiments were carried out with everted rat gut sacs, whereas in vitro metabolism experiments were conducted with rat liver microsomes and intestinal S9 fractions. Mucosal changes were evaluated with light microscopy and transmission electron microscopy. The results showed that, in rat plasma, LPS pretreatment increased systemic alkaloid exposure. LPS pretreatment increased the in vitro absorption of the alkaloids and decreased their efflux. The efflux of vinblastine and rhodamine 123, P-glycoprotein substrates, also was decreased. The absorption of fluorescein isothiocyanate-labeled dextran (average molecular mass, 4 kDa), a gut paracellular permeability probe, was not influenced. Obvious damage was observed in the mucosa, but the tight junctions between epithelial cells remained intact. Intestinal, rather than hepatic, alkaloid metabolism was decreased. These findings indicated that LPS pretreatment increased systemic exposure to the alkaloids through enhancement of their absorption, which was related to decreased intestinal efflux and metabolism. The results add to the understanding of why rhizoma coptidis is active despite the low plasma concentrations of the rhizoma coptidis alkaloids measured in normal subjects and experimental animals.

  7. Infrared Imaging of the Galaxies Responsible for z ~ 0.5O VI Absorption Systems

    NASA Astrophysics Data System (ADS)

    Prochaska, Jason X.; Chen, Hsiao-Wen; Mulchaey, John

    2001-02-01

    A comparison of the baryonic mass density inferred from BBN with a census of visible baryonic components (i.e. galaxies, clusters, HI gas) indicates a significant fraction of the universe's baryons are hidden in a dark component. Theoretical investigations into these 'missing' baryons suggest the majority lie in a hot (T ~ 10^6 K), low density medium which can only be efficiently detected through surveys for O VI absorption. Interestingly, recent STIS and FUSE searches for O VI are consistent with this gas comprising a significant fraction of the missing baryons. Establishing the physical nature of these O VI absorbers, therefore, may have large impact on our understanding of the distribution of baryons in the universe. In particular, it is important to determine if these systems arise in individual galactic halos, the intragroup or intracluster medium, the low density 'cosmic web' which connects collapsed objects, or a different region of the universe altogether. We are currently pursuing a program to search for galaxies associated with O VI absorbers at moderate redshift (z ~ 0.5). To accomplish this project, we must estimate photometric redshifts of the galaxies in the field (~ 8' × 8') surrounding the O VI absorbers in order to efficiently select candidates for follow-up spectroscopy. To this end, near-IR images are essential. With this proposal, we intend to obtain J and H band images of three fields surrounding four O VI absorbers in one night of observation with the Flamingos instrument. The results of this pilot program will help us to refine and focus our survey as well as double the number of O VI systems previously observed at z > 0.5.

  8. Optimal design of solid oxide fuel cell, ammonia-water single effect absorption cycle and Rankine steam cycle hybrid system

    NASA Astrophysics Data System (ADS)

    Mehrpooya, Mehdi; Dehghani, Hossein; Ali Moosavian, S. M.

    2016-02-01

    A combined system containing solid oxide fuel cell-gas turbine power plant, Rankine steam cycle and ammonia-water absorption refrigeration system is introduced and analyzed. In this process, power, heat and cooling are produced. Energy and exergy analyses along with the economic factors are used to distinguish optimum operating point of the system. The developed electrochemical model of the fuel cell is validated with experimental results. Thermodynamic package and main parameters of the absorption refrigeration system are validated. The power output of the system is 500 kW. An optimization problem is defined in order to finding the optimal operating point. Decision variables are current density, temperature of the exhaust gases from the boiler, steam turbine pressure (high and medium), generator temperature and consumed cooling water. Results indicate that electrical efficiency of the combined system is 62.4% (LHV). Produced refrigeration (at -10 °C) and heat recovery are 101 kW and 22.1 kW respectively. Investment cost for the combined system (without absorption cycle) is about 2917 kW-1.

  9. Large-scale environment of z ˜ 5.7 C IV absorption systems -II. Spectroscopy of Lyman α emitters

    NASA Astrophysics Data System (ADS)

    Díaz, C. Gonzalo; Ryan-Weber, Emma V.; Cooke, Jeff; Koyama, Yusei; Ouchi, Masami

    2015-04-01

    The flow of baryons to and from a galaxy, which is fundamental for galaxy formation and evolution, can be studied with galaxy-metal absorption system pairs. Our search for galaxies around C IV absorption systems at z ˜ 5.7 showed an excess of photometric Lyman α emitter (LAE) candidates in the fields J1030+0524 and J1137+3549. Here, we present spectroscopic follow-up of 33 LAEs in both fields. In the first field, three out of the five LAEs within 10h-1 projected comoving Mpc from the C IV system are within ±500 km s-1 from the absorption at z_{C IV}=5.7242± 0.0001. The closest candidate (LAE 103027+052419) is robustly confirmed at 212.8^{+14}_{-0.4}h^{-1} physical kpc from the C IV system. In the second field, the LAE sample is selected at a lower redshift (Δz ˜ 0.04) than the C IV absorption system as a result of the filter transmission and, thus, do not trace its environment. The observed properties of LAE 103027+052419 indicate that it is near the high-mass end of the LAE distribution, probably having a large H I column density and large-scale outflows. Therefore, our results suggest that the C IV system is likely produced by a star-forming galaxy which has been injecting metals into the intergalactic medium since z > 6. Thus, the C IV system is either produced by LAE 103027+052419, implying that outflows can enrich larger volumes at z > 6 than at z ˜ 3.5, or an undetected dwarf galaxy. In either case, C IV systems like this one trace the ionized intergalactic medium at the end of cosmic hydrogen reionization and may trace the sources of the ionizing flux density.

  10. Evaluation of knit glove fabrics as barriers to dermal absorption of organophosphorus insecticides using an in vitro test system.

    PubMed

    Keeble, V B; Correll, L; Ehrich, M

    1993-08-27

    Cotton and synthetic knit glove fabrics in combination with an in vitro skin model were used to examine the capability of fabric to decrease the dermal absorption of the organophosphorus insecticides azinphos-methyl, paraoxon, and malathion. Capability for inhibition of acetylcholinesterase was determined in samples of media taken from under the skin barrier after the skin model, with or without fabric protection, had been exposed to the test compounds for 4 h. Acetylcholinesterase inhibitions caused by the direct addition of organophosphorus insecticide to the media were also included in the comparison. Results indicated that the skin model system alone had some capability to serve as a barrier to the transfer of organophosphates. Fabric covering used on the test model increased the barrier between insecticide application and resultant acetylcholinesterase inhibition. The all-cotton, 7-cut knit was especially effective in preventing the absorption of azinphos-methyl, as this organophosphorus insecticide had no capability to cause acetylcholinesterase inhibition when this fabric was used to protect the skin model. Knit glove materials of 100% cotton were demonstrated to be effective in preventing the absorption of paraoxon and malathion. These studies indicate that an in vitro model system can be used in combination with fabrics to study the relationship between clothing and skin as barriers to the absorption of organophosphorus insecticides.

  11. Determining CDOM Absorption Spectra in Diverse Coastal Environments Using a Multiple Pathlength, Liquid Core Waveguide System. Measuring the Absorption of CDOM in the Field Using a Multiple Pathlength Liquid Waveguide System

    NASA Technical Reports Server (NTRS)

    Miller, Richard L.; Belz, Mathias; DelCastillo, Carlos; Trzaska, Rick

    2000-01-01

    We evaluated the accuracy, sensitivity and precision of a multiple pathlength, liquid core waveguide (MPLCW) system for measuring colored dissolved organic matter (CDOM) absorption in the UV-visible spectral range (370-700 nm). The MPLCW has four optical paths (2.0, 9.8, 49.3, and 204 cm) coupled to a single Teflon AF sample cell. Water samples were obtained from inland, coastal and ocean waters ranging in salinity from 0 to 36 PSU. Reference solutions for the MPLCW were made having a refractive index of the sample. CDOM absorption coefficients, a(sub CDOM), and the slope of the log-linearized absorption spectra, S, were compared with values obtained using a dual-beam spectrophotometer. Absorption of phenol red secondary standards measured by the MPLCW at 558 nm were highly correlated with spectrophotometer values (r > 0.99) and showed a linear response across all four pathlengths. Values of a(sub CDOM) measured using the MPLCW were virtually identical to spectrophotometer values over a wide range of concentrations. The dynamic range of a(sub CDOM) for MPLCW measurements was 0.002 - 231.5/m. At low CDOM concentrations (a(sub 370) < 0.1/m) spectrophotometric a(sub CDOM) were slightly greater than MPLCW values and showed larger fluctuations at longer wavelengths due to limitations in instrument precision. In contrast, MPLCW spectra followed an exponential to 600 nm for all samples. The maximum deviation in replicate MPLCW spectra was less than 0.001 absorbance units. The portability, sampling, and optical characteristics of a MPLCW system provide significant enhancements for routine CDOM absorption measurements in a broad range of natural waters.

  12. Effluent Storage and Biomat Occurrence among Septic System Absorption Field Architectures in a Typic Fragiudult.

    PubMed

    Prater, N J M; Brye, K R; Dunn, S; Soerens, T S; Sharpley, A N; Mason, E; Gbur, E E

    2013-07-01

    On-site wastewater treatment systems (OWTSs) are commonly used by households in areas of low population density to treat household wastewater and recycle it back to the environment. However, new absorption field products of differing architecture types have recently become available. A 3-yr field study was conducted in Bethel Heights, northwest Arkansas to assess several newer architecture types (i.e., chambers, polystyrene-aggregate, and gravel-less pipe) relative to the traditional pipe-and-gravel design under wet- and dry-soil conditions. Thirteen products of four different architecture types were installed in 46-cm-deep trenches in a Captina silt loam (fine-silty, siliceous, active, mesic Typic Fragiudult). Products were evaluated based on in-trench solution storage measured with an electronic water-level sensor approximately weekly from January 2009 through January 2012. Between May 2010 and January 2012, the thickness of any biomat formation was measured approximately weekly by insertion of a wooden dowel through in-trench monitoring ports. Architecture type alone did not affect ( > 0.05) in-trench solution storage. However, solution storage among individual products differed under wet- and dry-soil conditions ( < 0.05). When present, biomat thickness differed significantly ( < 0.05) among all four architecture types, ranging from 1.4 to 6.2 cm thick on average in the pipe-and-aggregate and polystyrene-aggregate types, respectively. Regression analyses showed that biomat thickness increased in three products, did not change in nine products, and decreased in one product over time. Results showed that several currently approved alternative products had similar in-trench solution storage but that several alternative products also had greater solution storage than that of the traditional pipe-and-gravel system. With no observed effluent surfacing, the soil morphology approach appears to be adequate and appropriately environmentally conservative for assigning

  13. Measured performance of a 3-ton LiBr absorption water chiller and its effect on cooling system operation

    NASA Technical Reports Server (NTRS)

    Namkoong, D.

    1976-01-01

    A 3-ton lithium bromide absorption water chiller was tested for a number of conditions involving hot-water input, chilled water, and the cooling water. The primary influences on chiller capacity were the hot water inlet temperature and the cooling water inlet temperature. One combination of these two parameters extended the output to as much as 125% of design capacity, but no combination could lower the capacity to below 60% of design. A cooling system was conceptually designed so that it could provide several modes of operation. Such flexibility is needed for any solar cooling system to be able to accommodate the varying solar energy collection and the varying building demand. It is concluded that a 3-ton absorption water chiller with the kind of performance that was measured can be incorporated into a cooling system such as that proposed, to provide efficient cooling over the specified ranges of operating conditions.

  14. Measured performance of a 3 ton LiBr absorption water chiller and its effect on cooling system operation

    NASA Technical Reports Server (NTRS)

    Namkoong, D.

    1976-01-01

    A three ton lithium bromide absorption water chiller was tested for a number of conditions involving hot water input, chilled water, and the cooling water. The primary influences on chiller capacity were the hot water inlet temperature and the cooling water inlet temperature. One combination of these two parameters extended the output to as much as 125% of design capacity, but no combination could lower the capacity to below 60% of design. A cooling system was conceptually designed so that it could provide several modes of operation. Such flexibility is needed for any solar cooling system to be able to accommodate the varying solar energy collection and the varying building demand. It was concluded that a three-ton absorption water chiller with the kind of performance that was measured can be incorporated into a cooling system such as that proposed, to provide efficient cooling over the specified ranges of operating conditions.

  15. Quasars as the formation sites of high-redshift ellipticals: a signature in the `associated' absorption-line systems?

    NASA Astrophysics Data System (ADS)

    Franceschini, A.; Gratton, R.

    1997-03-01

    Published data on the average metallicities and abundance ratios for absorption-line systems in high-redshift quasars suggest that a dichotomy may exist between the chemical composition of damped Lyman alpha (Lyalpha) systems (interpreted as intervening galaxies in the QSO line of sight) and the z_abs~=z_em absorption- line systems associated with the quasar. Intervening systems have smaller than solar metallicities, whereas associated absorbers have solar or greater than solar metallicities and small N/C ratios. While these results have to be confirmed by more precise abundance determinations, we argue that they may be explained by an early phase of efficient metal enrichment occurring only in the close environment of high-z QSOs, and characterized by an excess type-II supernova (SNII) activity. This is reminiscent of the SNII phase required to explain the abundance ratios (favouring alpha- over Fe-group elements) observed in the intracluster (IC) medium of local galaxy clusters. We explore the following scenario, to be tested by forthcoming observations of QSO absorption lines using very large optical telescopes. (a) Well-studied damped- Lyalpha, Lyalpha and metal lines in intervening systems trace only part of the history of metal production in the Universe - the one concerning slowly star-forming discs or dwarf irregulars. (b) The complementary class of early-type and bulge-dominated galaxies formed quickly (at z>~4-5) through a huge episode of star formation favouring high-mass stars. (c) The nucleus of the latter is the site of the subsequent formation of a quasar, which partly hides from view the dimmer host galaxy. (d) The products of a galactic wind, following the violent episode of star formation in the host galaxy and metal pollution of the IC medium in the forming cluster, could be directly observable in the z_abs~=z_em associated absorption systems on the QSO line of sight.

  16. [Development of a photoacoustic spectroscopy system for the measurement of absorption coefficient of atmospheric aerosols].

    PubMed

    Liu, Qiang; Niu, Ming-Sheng; Wang, Gui-Shi; Cao, Zhen-Song; Liu, Kun; Chen, Wei-Dong; Gao, Xiao-Ming

    2013-07-01

    In the present paper, the authors focus on the effect of the resonance frequency shift due to the changes in temperature and humidity on the PA signal, present several methods to control the noise derived form gas flow and vibration from the sampling pump. Based on the efforts mentioned above, a detection limit of 1.4 x 10(-8) W x cm(-1) x Hz(-1/2) was achieved for the measurement of atmospheric aerosols absorption coefficient. During the experiments, the PA cell was calibrated with the absorption of standard NO2 gas at 532 nm and the atmospheric aerosols were measured continuously. The measurement results show that the PAS is suitable for the real-time measurement of the absorption coefficient of atmospheric aerosols in their natural suspended state. PMID:24059163

  17. Gastrointestinal absorption of lead in chicks: involvement of the cholecalciferol endocrine system

    SciTech Connect

    Edelstein, S.; Fullmer, C.S.; Wasserman, R.H.

    1984-04-01

    The role of dietary calcium and phosphorus in modifying the intestinal absorption of lead and also the effect of lead ingestion on the metabolism of cholecalciferol were studied in chicks. The efficiency of absorption of /sup 203/Pb and /sup 47/Ca was increased when the animals were fed a low calcium diet and treated with cholecalciferol. The synthesis of the vitamin D-induced calcium-binding protein (CaBP) was correspondingly increased. When the chicks were depleted of vitamin D and repleted with 1,25-dihydroxycholecalciferol (1,25(OH)/sub 2/D/sub 3/) as their only source of the vitamin, the absorption of both /sup 47/Ca and /sup 203/Pb was unaffected by dietary calcium levels, and no change in CaBP levels occurred. Low dietary intake of phosphorus resulted in an increase in /sup 47/Ca and /sup 203/Pb absorption and in CaBP synthesis when the animals were treated with cholecalciferol. However, when the birds were repleted with 1,25(OH)/sub 2/D/sub 3/, the intestinal absorption of /sup 47/Ca and of /sup 203/Pb was increased, as well as the intestinal CaBP levels. Intracardial injection of increasing doses of 1,25(OH)/sub 2/D/sub 3/ to rachitic chicks resulted in a concomitant increase in /sup 203/Pb absorption in a manner that correlated with the degree of synthesis of CaBP. Ingestion of lead by the chicks was found to impair growth and renal production of 1,25(OH)/sub 2/D/sub 3/, resulting in lowered circulating and intestinal content of the hydroxylated metabolites of cholecalciferol.

  18. The Large Bright QSO Survey for Damped LY alpha Absorption Systems

    NASA Astrophysics Data System (ADS)

    Wolfe, Arthur M.; Lanzetta, Kenneth M.; Foltz, Craig B.; Chaffee, Frederic H.

    1995-12-01

    We present a new survey for damped Lyα systems with redshifts z ~ 1.6-3.0. The survey is based on a sample of 228 QSOs drawn from the Large Bright QSO Survey (LBQS). We find a total of 20 candidate damped Lyα lines with rest frame equivalent widths determined from low- resolution spectroscopy of W >= 10 A. Using intermediate-resolution spectroscopy, we and other workers confirm 12 of these candidates and an additional candidate with W < 10 A as damped Lyα systems with H I column densities N(H I) >= 2 x 10^20^ cm^-2^. All the systems were drawn from a redshift path {DELTA}z = 121.0 along which it is possible to detect damped Lyα candidates with W >= 5 A at 5 σ, statistical significance. We combine the results of the LBQS damped survey with results of previous surveys for damped systems to form a "statistical sample" of 62 damped Lyα systems with N(H I) >= 2 x 10^20^ cm^-2^ These systems are drawn from a total redshift path {DELTA}z = 323.8. A list of 18 additional damped Lyα systems not found in systematic surveys is also presented. Therefore, we are aware of 80 damped Lyα absorption systems at the time of writing (1995 March) with N(H I) >= 2 x 10^20^ cm^-2^. The following is a summary of results based on the "statistical sample." 1. The LBQS damped survey increases the sensitivity for finding damped Lyα systems in the redshift interval z ~ 1.6-2.5. 2. Using the "statistical sample," we find that the quantity n(z), the number of absorbers per unit redshift interval with N(H I) >= 2 x 10^20^ cm^-2^, shows no evidence for intrinsic evolution. The new n(z) exhibits little scatter around a systematic increase of n(z) with z and is in excellent agreement with our previous determination of n(z). 3. Our determination of {OMEGA}_g_(z), the comoving mass density of neutral gas at redshift z, shows a monotonically increasing form of {OMEGA}_g_(z) with z for the first time. The new data support and strengthen the earlier conclusion that the comoving density of

  19. Broadband and wide angle light absorption for an aluminum nanorod array in a prism-coupling system

    NASA Astrophysics Data System (ADS)

    Jen, Yi-Jun; Dai, Jia-Wei; Chao, Jung-Hui

    2013-09-01

    Traditional optical thin films exhibit low absorption when light is incident obliquely because the optical path decreases with increasing angle of incidence [1]. A thin film absorber is also a challenge to perform high absorption at oblique incidence. Under the condition of total reflection, a thin metal film with thickness around 40nm in a Kretschmann configuration (prism / metal film / air) enables to absorb light at an extremely small angle range by exciting surface plasmon at the interface of metal/air [2]. In this work, a metamaterial thin film composed of aluminum nanorods is fabricated and used to absorb light in high efficiency. An aluminum nanorod array (Al NRA) deposited obliquely is arranged in a prism-coupling system to observed the reflection under the condition of total reflection of the system: BK7 prism/ Al NRA/ Air. The Al NRA is 184nm thick and tilted at an angle of 35° with respect to the surface normal. The deposition plane defined by the directions of rod and surface normal is orientated at angles of φ=0° and φ=180° with respect to the plane of incidence to measure the reflectance versus incident angles from 45° to 70° and wavelengths from 400nm to 700nm. The definition of the NRAs orientation is shown in Fig. 3. When the deposition plane is the same with the plane of incidence, the reflectance spectra indicate that the Al NRA exhibits strong absorptance over 80% at angles of incidence from 45° to 55° for both p-polarization and s-polarization. The enhanced p-polarized absorptance is extended from 45° to 70°. At φ=90°, the absorptance is weaker at angles of incidence from 55° to 70° compared with other two cases measured at φ=0° and φ=180°°.

  20. Influence of food on the absorption of metoprolol administered as an Oros drug delivery system to man.

    PubMed

    Lecaillon, J B; Massias, P; Schoeller, J P; Abadie, F

    1985-01-01

    The influence of food on the release, absorption and metabolism of metoprolol has been studied after single administration of a 19/190 Oros system to eight healthy volunteers on four occasions, once after an overnight fast, and just before each of three daily meals (breakfast, lunch and dinner). The plasma concentration-time profiles under the four test conditions were virtually identical, and no statistically significant differences in mean areas under the curves between 0 and 32 h, peak concentrations, or times to peak, were detected. The absorption of metoprolol was unaffected by food intake, with 80-90% of the amount absorbed reaching the systemic circulation within 10 h. The ratios of areas under the curve for alpha-hydroxymetoprolol to its parent drug were in the same range for the four treatments, and similar to those reported after conventional tablets. The in vivo release and absorption of drug from the Oros system and its systemic availability, were not influenced by concomitant ingestion of food.

  1. Third-order nonlinear optical properties of colloidal Au nanorods systems: saturable and reverse-saturable absorption.

    PubMed

    García-Ramírez, E V; Almaguer-Valenzuela, S; Sánchez-Dena, O; Baldovino-Pantaleón, O; Reyes-Esqueda, J A

    2016-01-25

    In this work, we present a study of the nonlinear absorption properties from different gold nanorod (NR) systems in aqueous suspension. The NRs were obtained with the bottom-up protocol by the seed-mediated growth method (SMG), using Ag(+) ions at different concentrations, and CTAB as surfactant. By using this method, aspect ratios between 2 and 5 were obtained. The transverse surface plasmons (TSP) are located between 514 - 535 nm, while the longitudinal surface plasmons (LSP) are between 639 - 921 nm, for the different samples studied. The Z-scan technique was implemented for open (OA) and closed (CA) aperture at 532 and 1064 nm, with laser pulses of 26 ps, for vertical and horizontal polarizations, with respect to the incidence plane (horizontal). At 532 nm all samples showed saturable absorption (SA), while for samples with LSP near 1064 nm, such effect was observed only at low-energy pulse experimental conditions. In the high-energy pulse regime, an apparent reverse-saturable absorption (RSA) was observed for both wavelengths. However for 532 nm, it was possible to determine that this effect results from structural changes in the samples, which are manifested through the behavior of nonlinear absorption and refraction curves. These results were used to determine the irradiances to which NRs can be modified by photodegradation. PMID:26832569

  2. Mode of oral iron administration and the amount of iron habitually consumed do not affect iron absorption, systemic iron utilisation or zinc absorption in iron-sufficient infants: a randomised trial.

    PubMed

    Szymlek-Gay, Ewa A; Domellöf, Magnus; Hernell, Olle; Hurrell, Richard F; Lind, Torbjörn; Lönnerdal, Bo; Zeder, Christophe; Egli, Ines M

    2016-09-01

    Different metabolic pathways of supplemental and fortification Fe, or inhibition of Zn absorption by Fe, may explain adverse effects of supplemental Fe in Fe-sufficient infants. We determined whether the mode of oral Fe administration or the amount habitually consumed affects Fe absorption and systemic Fe utilisation in infants, and assessed the effects of these interventions on Zn absorption, Fe and Zn status, and growth. Fe-sufficient 6-month-old infants (n 72) were randomly assigned to receive 6·6 mg Fe/d from a high-Fe formula, 1·3 mg Fe/d from a low-Fe formula or 6·6 mg Fe/d from Fe drops and a formula with no added Fe for 45 d. Fractional Fe absorption, Fe utilisation and fractional Zn absorption were measured with oral (57Fe and 67Zn) and intravenous (58Fe and 70Zn) isotopes. Fe and Zn status, infection and growth were measured. At 45 d, Hb was 6·3 g/l higher in the high-Fe formula group compared with the Fe drops group, whereas serum ferritin was 34 and 35 % higher, respectively, and serum transferrin 0·1 g/l lower in the high-Fe formula and Fe drops groups compared with the low-Fe formula group (all P<0·05). No intervention effects were observed on Fe absorption, Fe utilisation, Zn absorption, other Fe status indices, plasma Zn or growth. We concluded that neither supplemental or fortification Fe nor the amount of Fe habitually consumed altered Fe absorption, Fe utilisation, Zn absorption, Zn status or growth in Fe-sufficient infants. Consumption of low-Fe formula as the only source of Fe was insufficient to maintain Fe stores.

  3. Mode of oral iron administration and the amount of iron habitually consumed do not affect iron absorption, systemic iron utilisation or zinc absorption in iron-sufficient infants: a randomised trial.

    PubMed

    Szymlek-Gay, Ewa A; Domellöf, Magnus; Hernell, Olle; Hurrell, Richard F; Lind, Torbjörn; Lönnerdal, Bo; Zeder, Christophe; Egli, Ines M

    2016-09-01

    Different metabolic pathways of supplemental and fortification Fe, or inhibition of Zn absorption by Fe, may explain adverse effects of supplemental Fe in Fe-sufficient infants. We determined whether the mode of oral Fe administration or the amount habitually consumed affects Fe absorption and systemic Fe utilisation in infants, and assessed the effects of these interventions on Zn absorption, Fe and Zn status, and growth. Fe-sufficient 6-month-old infants (n 72) were randomly assigned to receive 6·6 mg Fe/d from a high-Fe formula, 1·3 mg Fe/d from a low-Fe formula or 6·6 mg Fe/d from Fe drops and a formula with no added Fe for 45 d. Fractional Fe absorption, Fe utilisation and fractional Zn absorption were measured with oral (57Fe and 67Zn) and intravenous (58Fe and 70Zn) isotopes. Fe and Zn status, infection and growth were measured. At 45 d, Hb was 6·3 g/l higher in the high-Fe formula group compared with the Fe drops group, whereas serum ferritin was 34 and 35 % higher, respectively, and serum transferrin 0·1 g/l lower in the high-Fe formula and Fe drops groups compared with the low-Fe formula group (all P<0·05). No intervention effects were observed on Fe absorption, Fe utilisation, Zn absorption, other Fe status indices, plasma Zn or growth. We concluded that neither supplemental or fortification Fe nor the amount of Fe habitually consumed altered Fe absorption, Fe utilisation, Zn absorption, Zn status or growth in Fe-sufficient infants. Consumption of low-Fe formula as the only source of Fe was insufficient to maintain Fe stores. PMID:27546308

  4. Properties of the Carrol system and a machine design for solar-powered, air cooled, absorption space cooling

    NASA Astrophysics Data System (ADS)

    1981-05-01

    The name Carrol was selected as a convenient shorthand designation for a prime candidate chemical system comprising ethylene glycol-lithium bromide as an absorbent mixture with water as a refrigerant. The instrumentation, methods of handling data and numerical results from a systematic determination of Carrol property data required to design an air cooled absorption machine based on this chemical system are described. These data include saturation temperature, relative enthalpy, density, specific heat capacity, thermal conductivity, viscosity and absorber film heat transfer coefficient as functions of solution temperature and Carrol concentration over applicable ranges. For each of the major components of the absorption chiller, i.e., generator, chiller, absorber, condenser, heat exchanger, purge and controls, the report contains an assembly drawing and the principal operating characteristics of that component.

  5. On Different Absorption Components in the X-ray Spectra of the Intermediate Polar Systems

    NASA Astrophysics Data System (ADS)

    Balman, S.; Okcu, B.

    2014-07-01

    We present orbital phase-resolved spectroscopy of the Intermediate polars (IP) AO Psc, HT Cam, V1223 Sgr and XSS J0056+4548 using the XMM-Newton EPIC pn data. We detect increase of absorption by neutral hydrogen column density N_{H} during the phases corresponding to the orbital minima in a range ˜ (1.0-2.0)× 10^{22} cm^{-2}. AO Psc indicates spectral hardening in the soft plasma emission component. HT Cam, reveals an increase of N_{H} at the orbital minimum from 0.05× 10^{22} cm^{-2} to 0.13× 10^{22} cm^{-2}. These high N_{H} values are most likely a result of absorption by the bulge material at the accretion impact zone. We discuss implications of this interms of warmabsorbers in IPs and bulge temperatures. The four IPs reveal a second high absorption component that is constant over the orbital phase in a range (5.0-11.0)× 10^{22} cm^{-2}. We attribute this component to the accretion column/curtain. These results are in accordance with the orbital phase-resolved analysis presented in Pekon & Balman (2011) for EX Hya and (2012) for FO Aqr. We strongly suggest that absorption by the bulge at the accretion impact zone is a distinct component in the IP X-ray spectra.

  6. Development and operation of a real-time data acquisition system for the NASA-LaRC differential absorption lidar

    NASA Technical Reports Server (NTRS)

    Butler, C.

    1985-01-01

    Computer hardware and software of the NASA multipurpose differential absorption lidar (DIAL) sysatem were improved. The NASA DIAL system is undergoing development and experimental deployment for remote measurement of atmospheric trace gas concentration from ground and aircraft platforms. A viable DIAL system was developed with the capability of remotely measuring O3 and H2O concentrations from an aircraft platform. Test flights were successfully performed on board the NASA/Goddard Flight Center Electra aircraft from 1980 to 1984. Improvements on the DIAL data acquisition system (DAS) are described.

  7. Intranasal administration of neuropeptide Y in man: systemic absorption and functional effects.

    PubMed Central

    Lacroix, J. S.; Ricchetti, A. P.; Morel, D.; Mossimann, B.; Waeber, B.; Grouzmann, E.

    1996-01-01

    1. Exogenous neuropeptide Y (NPY, 10 nmol, 50 nmol and 100 nmol) and its vehicle (NaCl 0.9%) were administered in a double blind, randomized and controlled manner by intranasal spray in 7 healthy volunteers. Variations of plasma NPY concentration over time were measured during 120 min. Forty min after the administration of 50 nmol and 100 nmol of exogenous NPY, plasma NPY increased from 5.5 +/- 1.1 pM to 9.8 +/- 2.3 pM (P < 0.05) and from 9.06 +/- 5.1 pM to 20.8 +/- 6.16 pM (P < 0.001), respectively. There was no significant modification of the mean arterial blood pressure and no subjective discomfort was reported. 2. Nasal airway resistance (NAR) was measured by anterior rhinomanometry and was reduced by 25 +/- 3% and 32 +/- 5% after the spray of 50 nmol and 100 nmol, respectively, for about 90 min. 3. Double-blind, randomized, placebo-controlled and 3-way crossover design experiments were performed in 8 healthy volunteers to evaluate the influence of intranasal pretreatment with NPY (20 nmol) and the mixed alpha 1/alpha 2-adrenoceptor agonist oxymetazoline (20 nmol) on the functional effects of subsequent local irritation evoked by capsaicin (3.3 x 10(-4) mol). Subjective evaluation of NAR and local intensity of discomfort were evaluated by means of a visual analogue scale. Nasal secretions were collected and objective NAR was recorded by rhinomanometry. 4. Subjective NAR, nasal secretions and rhinomanometry recordings were not modified by intranasal application of saline, NPY or oxymetazoline. Subjective nasal obstruction, local discomfort, nasal secretions and NAR increase evoked by capsaicin were markedly reduced by NPY pretreatment (P < 0.05) when compared to saline or oxymetazoline. 5. It is concluded that intranasal application of exogenous NPY has very low systemic absorption but induced long lasting nasal vasoconstriction without cardiovascular effects. Pretreatment of the nasal mucosa with exogenous NPY reduces both secretagogue and vasodilator responses

  8. An instrumented pendulum system for measuring energy absorption during fracture insult to large animal joints in vivo.

    PubMed

    Diestelmeier, B W; Rudert, M J; Tochigi, Y; Baer, T E; Fredericks, D C; Brown, T D

    2014-06-01

    For systematic laboratory studies of bone fractures in general and intra-articular fractures in particular, it is often necessary to control for injury severity. Quantitatively, a parameter of primary interest in that regard is the energy absorbed during the injury event. For this purpose, a novel technique has been developed to measure energy absorption in experimental impaction. The specific application is for fracture insult to porcine hock (tibiotalar) joints in vivo, for which illustrative intra-operative data are reported. The instrumentation allowed for the measurement of the delivered kinetic energy and of the energy passed through the specimen during impaction. The energy absorbed by the specimen was calculated as the difference between those two values. A foam specimen validation study was first performed to compare the energy absorption measurements from the pendulum instrumentation versus the work of indentation performed by an MTS machine. Following validation, the pendulum apparatus was used to measure the energy absorbed during intra-articular fractures created in 14 minipig hock joints in vivo. The foam validation study showed close correspondence between the pendulum-measured energy absorption and MTS-performed work of indentation. In the survival animal series, the energy delivered ranged from 31.5 to 48.3 Js (41.3±4.0, mean±s.d.) and the proportion of energy absorbed to energy delivered ranged from 44.2% to 64.7% (53.6%±4.5%). The foam validation results support the reliability of the energy absorption measure provided by the instrumented pendulum system. Given that a very substantial proportion of delivered energy passed--unabsorbed--through the specimens, the energy absorption measure provided by this novel technique arguably provides better characterization of injury severity than is provided simply by energy delivery.

  9. Förster resonance energy transfer, absorption and emission spectra in multichromophoric systems. III. Exact stochastic path integral evaluation

    SciTech Connect

    Moix, Jeremy M.; Ma, Jian; Cao, Jianshu

    2015-03-07

    A numerically exact path integral treatment of the absorption and emission spectra of open quantum systems is presented that requires only the straightforward solution of a stochastic differential equation. The approach converges rapidly enabling the calculation of spectra of large excitonic systems across the complete range of system parameters and for arbitrary bath spectral densities. With the numerically exact absorption and emission operators, one can also immediately compute energy transfer rates using the multi-chromophoric Förster resonant energy transfer formalism. Benchmark calculations on the emission spectra of two level systems are presented demonstrating the efficacy of the stochastic approach. This is followed by calculations of the energy transfer rates between two weakly coupled dimer systems as a function of temperature and system-bath coupling strength. It is shown that the recently developed hybrid cumulant expansion (see Paper II) is the only perturbative method capable of generating uniformly reliable energy transfer rates and emission spectra across a broad range of system parameters.

  10. The spatial and kinematic structure of QSO metal-line absorption systems

    NASA Technical Reports Server (NTRS)

    Lanzetta, Kenneth M.

    1992-01-01

    Recent attempts to infer the spatial and kinematic distributions of the material responsible for absorption lines observed in the spectra of background QSOs are presented. Current models of the absorbing regions are compared, and initial observational results are described. This research is expected to lead eventually to a detailed picture of the extended gaseous halo regions of galaxies at early evolutionary stages and to an understanding of the physical processes at work in these halos.

  11. Three dimensional mapping of absorption defects at 355 nm for potassium dihydrogen phosphate (KDP) used in high power laser systems

    NASA Astrophysics Data System (ADS)

    Chen, Jian; Dong, Jingtao; Zhang, Qi; Wu, Zhouling

    2014-10-01

    Potassium dihydrogen phosphate (KDP) is commonly used for frequency conversion and optical switching applications in many high-power laser systems. Such applications require high damage threshold of KDP crystals. Damage behavior of KDP has been investigated for many years, and the results show that intrinsic or extrinsic defects are responsible for highly localized absorption in KDP materials, and that in turn will cause the laser damage. In this paper, we studied the absorption properties of KDP crystals at wavelengths of 355 nm by using a three-dimensional (3D) photothermal microscope. Several 3D images of the bulk defects were obtained. The results indicated that both surface defects and bulk defects can be determined and analyzed using the 3-D photothermal microscope. Our results indicate that 3D photothermal microscopy is a powerful tool for defect characterization of optical materials for high power laser applications.

  12. The Hubble Space Telescope quasar absorption line key project. 6: Properties of the metal-rich systems

    NASA Technical Reports Server (NTRS)

    Bergeron, Jacqueline; Petitjean, Patrick; Sargent, W. L. W.; Bahcall, John N.; Boksenberg, Alec; Hartig, George F.; Jannuzi, Buell T.; Kirhakos, Sofia; Savage, Blair D.; Schneider, Donald P.

    1994-01-01

    We present an analysis of the properties of a sample of 18 metal-rich, low-redshift z(sub abs) much less than z(sub em) absorbers seen in low- and medium-resolution spectra obtained for the Quasar Absorption Line Key Project with the Hubble Space Telescope Faint Object Spectrograph (HST/FOS). For most of the C IV and Lyman-limit systems, observations in the optical wavelength range of the expected associated Mg II absorption are available. As at high redshift (z approximately 2), there are two subclasses of absorbers which are characterized by the presence or absence of MG II absorption. However, some low-redshift Mg II and Fe absorptions originate from regions optically thin to UV ionizing photons and thus, at low redshift, the low-ionization systems do not always trace high opacities, as is the case at high redshift. This implies that the mean ionization state of metal-rich, optically thin absorbing clouds falls with decreasing redshift, which is consistent with the hypothesis that the gas is photoionized by the metagalactic UV background radiation field. Two main constraints are derived from the analysis of the Lyman-limit sample, assuming photoionization models are valid. First, a low opacity to ionizing photons (tau(sub LL) approximately less than 1), as observed for several Mg II-Fe II systems at z approximately 0.5, sets limits on the ionization level of hydrogen, thus on the total hydrogen column density and the heavy element abundances, (Z/H) approximately -0.5 to -0.3. Second, the dimensions of individual Mg II clouds are smaller than at high redshift by a factor 3-10. At z approximately greater than 0.6, the O VI absorption doublet is detected in four of the five z(sub abs) much less than z(sub em) systems for which the O VI wavelength range has been observed, whereas the associated N V doublet is detected in only two cases. This suggests that the presence of a high-ionization O VI phase is a general property of z approximately 0.6-1 absorption systems

  13. 41 CFR 102-37.535 - What information must FAA provide to GSA on its administration of the public airport donation...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... FAA provide to GSA on its administration of the public airport donation program? 102-37.535 Section... (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY Donations to Public Airports § 102-37.535 What information must FAA provide to GSA on its administration...

  14. 41 CFR 102-2.100 - Must agencies provide GSA with a follow-up analysis of their experience in deviating from the FMR?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... GSA with a follow-up analysis of their experience in deviating from the FMR? 102-2.100 Section 102-2... § 102-2.100 Must agencies provide GSA with a follow-up analysis of their experience in deviating from... the Regulatory Secretariat's address (see § 102-2.90) to describe their experiences in using...

  15. 77 FR 5252 - Federal Travel Regulation; GSA E-Gov Travel Service (ETS) Transition to E-Gov Travel Service 2...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-02

    ... ADMINISTRATION Federal Travel Regulation; GSA E-Gov Travel Service (ETS) Transition to E-Gov Travel Service 2... of a bulletin. SUMMARY: The attached bulletin announces GSA ETS Transition to ETS2. DATES: Effective.... Frank Robinson, ETS Program Manager Center for Travel Management (QMCD), Office of Travel...

  16. 41 CFR 102-34.335 - How do I submit information to the General Services Administration (GSA) for the Federal Fleet...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... information to the General Services Administration (GSA) for the Federal Fleet Report (FFR)? 102-34.335... (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE MANAGEMENT Federal Fleet Report... Fleet Report (FFR)? (a) Annually, agencies must submit to GSA the information needed to produce the...

  17. Proposed draft document for GSA office waste removal and procurement of densified refuse derived fuel for use as a supplemental fuel in GAS operated boilers

    NASA Astrophysics Data System (ADS)

    Campbell, J. A.

    1981-09-01

    A contract specifying waste collection and disposal from buildings managed by Government Services Administration (GSA) in the Washington, D. C. area and the production and delivery of pelletized fuel for burning with coal in one or two GSA steam generating plants is given.

  18. 41 CFR 300-80.5 - What factors will GSA consider in approving a request for a relocation expenses test program?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 4 2012-07-01 2012-07-01 false What factors will GSA... EXPENSES TEST PROGRAMS § 300-80.5 What factors will GSA consider in approving a request for a relocation expenses test program? The following factors will be considered: (a) Potential savings to the...

  19. 41 CFR 102-37.535 - What information must FAA provide to GSA on its administration of the public airport donation...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What information must FAA provide to GSA on its administration of the public airport donation program? 102-37.535 Section... Donations to Public Airports § 102-37.535 What information must FAA provide to GSA on its administration...

  20. Förster resonance energy transfer, absorption and emission spectra in multichromophoric systems. I. Full cumulant expansions and system-bath entanglement

    SciTech Connect

    Ma, Jian; Cao, Jianshu

    2015-03-07

    We study the Förster resonant energy transfer rate, absorption and emission spectra in multichromophoric systems. The multichromophoric Förster theory (MCFT) is determined from an overlap integral of generalized matrices related to the donor’s emission and acceptor’s absorption spectra, which are obtained via a full 2nd-order cumulant expansion technique developed in this work. We calculate the spectra and MCFT rate for both localized and delocalized systems, and calibrate the analytical 2nd-order cumulant expansion with the exact stochastic path integral method. We present three essential findings: (i) The role of the initial entanglement between the donor and its bath is found to be crucial in both the emission spectrum and the MCFT rate. (ii) The absorption spectra obtained by the cumulant expansion method are nearly identical to the exact spectra for both localized and delocalized systems, even when the system-bath coupling is far from the perturbative regime. (iii) For the emission spectra, the cumulant expansion can give reliable results for localized systems, but fail to provide reliable spectra of the high-lying excited states of a delocalized system, when the system-bath coupling is large and the thermal energy is small. This paper also provides a simple golden-rule derivation of the MCFT, reviews existing methods, and motivates further developments in the subsequent papers.

  1. Ca II AND Na I QUASAR ABSORPTION-LINE SYSTEMS IN AN EMISSION-SELECTED SAMPLE OF SDSS DR7 GALAXY/QUASAR PROJECTIONS. I. SAMPLE SELECTION

    SciTech Connect

    Cherinka, B.; Schulte-Ladbeck, R. E.

    2011-10-15

    The aim of this project is to identify low-redshift host galaxies of quasar absorption-line systems by selecting galaxies that are seen in projection onto quasar sightlines. To this end, we use the Seventh Data Release of the Sloan Digital Sky Survey to construct a parent sample of 97,489 galaxy/quasar projections at impact parameters of up to 100 kpc to the foreground galaxy. We then search the quasar spectra for absorption-line systems of Ca II and Na I within {+-}500 km s{sup -1} of the galaxy's velocity. This yields 92 Ca II and 16 Na I absorption systems. We find that most of the Ca II and Na I systems are sightlines through the Galactic disk, through high-velocity cloud complexes in our halo, or Virgo Cluster sightlines. Placing constraints on the absorption line rest equivalent width significance ({>=}3.0{sigma}), the local standard of rest velocity along the sightline ({>=}345 km s{sup -1}), and the ratio of the impact parameter to the galaxy optical radius ({<=}5.0), we identify four absorption-line systems that are associated with low-redshift galaxies at high confidence, consisting of two Ca II systems (one of which also shows Na I) and two Na I systems. These four systems arise in blue, {approx}L*{sub r} galaxies. Tables of the 108 absorption systems are provided to facilitate future follow-up.

  2. Effect on the Gastrointestinal Absorption of Drugs from Different Classes in the Biopharmaceutics Classification System, When Treating with Liraglutide.

    PubMed

    Malm-Erjefält, Monika; Ekblom, Marianne; Vouis, Jan; Zdravkovic, Milan; Lennernäs, Hans

    2015-11-01

    Like other GLP-1 receptor agonists used for treatment of type 2 diabetes, liraglutide delays gastric emptying. In this clinical absorption study, the primary objective was to investigate the effect of liraglutide (at steady state) on the rate and/or extent of gastrointestinal (GI) absorption of concomitantly orally taken drugs from three classes of the Biopharmaceutics Classification System (BCS). To provide a general prediction on liraglutide drug-drug absorption interaction, single-dose pharmacokinetics of drugs representing BCS classes II (low solubility-high permeability; atorvastatin 40 mg and griseofulvin 500 mg), III (high solubility-low permeability; lisinopril 20 mg), and IV (low solubility-low permeability; digoxin 1 mg) were studied in healthy subjects at steady state of liraglutide 1.8 mg, or placebo, in a two-period crossover design. With liraglutide, the oral drugs atorvastatin, lisinopril, and digoxin showed delayed tmax (by ≤2 h) and did not meet the criterion for bioequivalence for Cmax (reduced Cmax by 27-38%); griseofulvin had similar tmax and 37% increased Cmax. Although the prespecified bioequivalence criterion was not met by all drugs, the overall plasma exposure (AUC) of griseofulvin, atorvastatin, lisinopril, and digoxin only exhibited minor changes and was not considered to be of clinical relevance.

  3. The mechanism and properties of bio-photon emission and absorption in protein molecules in living systems

    NASA Astrophysics Data System (ADS)

    Pang, Xiao-feng

    2012-05-01

    The mechanism and properties of bio-photon emission and absorption in bio-tissues were studied using Pang's theory of bio-energy transport, in which the energy spectra of protein molecules are obtained from the discrete dynamic equation. From the energy spectra, it was determined that the protein molecules could both radiate and absorb bio-photons with wavelengths of <3 μm and 5-7 μm, consistent with the energy level transitions of the excitons. These results were consistent with the experimental data; this consisted of infrared absorption data from collagen, bovine serum albumin, the protein-like molecule acetanilide, plasma, and a person's finger, and the laser-Raman spectra of acidity I-type collagen in the lungs of a mouse, and metabolically active Escherichia coli. We further elucidated the mechanism responsible for the non-thermal biological effects produced by the infrared light absorbed by the bio-tissues, using the above results. No temperature rise was observed; instead, the absorbed infrared light promoted the vibrations of amides as well the transport of the bio-energy from one place to other in the protein molecules, which changed their conformations. These experimental results, therefore, not only confirmed the validity of the mechanism of bio-photon emission, and the newly developed theory of bio-energy transport mentioned above, but also explained the mechanism and properties of the non-thermal biological effects produced by the absorption of infrared light by the living systems.

  4. QSO ABSORPTION SYSTEMS DETECTED IN Ne VIII: HIGH-METALLICITY CLOUDS WITH A LARGE EFFECTIVE CROSS SECTION

    SciTech Connect

    Meiring, J. D.; Tripp, T. M.; Werk, J. K.; Prochaska, J. X.; Howk, J. C.; Jenkins, E. B.; Lehner, N.; Sembach, K. R.

    2013-04-10

    Using high-resolution, high signal-to-noise ultraviolet spectra of the z{sub em} = 0.9754 quasar PG1148+549 obtained with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope, we study the physical conditions and abundances of Ne VIII+O VI absorption line systems at z{sub abs} = 0.68381, 0.70152, 0.72478. In addition to Ne VIII and O VI, absorption lines from multiple ionization stages of oxygen (O II, O III, O IV) are detected and are well aligned with the more highly ionized species. We show that these absorbers are multiphase systems including hot gas (T Almost-Equal-To 10{sup 5.7} K) that produces Ne VIII and O VI, and the gas metallicity of the cool phase ranges from Z = 0.3 Z{sub Sun} to supersolar. The cool ( Almost-Equal-To 10{sup 4} K) phases have densities n{sub H} Almost-Equal-To 10{sup -4} cm{sup -3} and small sizes (<4 kpc); these cool clouds are likely to expand and dissipate, and the Ne VIII may be within a transition layer between the cool gas and a surrounding, much hotter medium. The Ne VIII redshift density, dN/dz{approx}7{sup +7}{sub -3}, requires a large number of these clouds for every L > 0.1 L* galaxy and a large effective absorption cross section ({approx}> 100 kpc), and indeed, we find a star-forming {approx}L {sup *} galaxy at the redshift of the z{sub abs} = 0.72478 system, at an impact parameter of 217 kpc. Multiphase absorbers like these Ne VIII systems are likely to be an important reservoir of baryons and metals in the circumgalactic media of galaxies.

  5. GSA's Teacher Advocate Program - getting teachers to be advocates for Earth Science

    NASA Astrophysics Data System (ADS)

    Lewis, G. B.

    2011-12-01

    After parents, teachers are they most influential people when it comes to students leaning about their world. However, when it comes to Earth science, the vast majority of our teachers have little to no Earth science training and lack the resources to run exciting and challenging classes on Earth science topics for their students. The Geological Society of America (GSA) is committed to reversing that trend by developing easy to use resources and training teachers on how to use them in their classrooms. Through a program called the Teacher Advocate Program (TAP), GSA has already had teachers using Earth science materials with over 6 million students (1.3 million a year). Formally established in 2003, TAP aims to raise the number of teachers who are advocates for geoscience in their classrooms, schools and school districts by providing those teachers with: Low cost teaching resources that provide them with teaching notes, teaching materials (images, models etc) and usable class room activities. Low cost training opportunities for teachers on how to use TAP materials. In-field experiences for teachers to provide them with teaching materials and insights.

  6. Critical coupling and coherent perfect absorption for ranges of energies due to a complex gain and loss symmetric system

    SciTech Connect

    Hasan, Mohammad; Ghatak, Ananya; Mandal, Bhabani Prasad

    2014-05-15

    We consider a non-Hermitian medium with a gain and loss symmetric, exponentially damped potential distribution to demonstrate different scattering features analytically. The condition for critical coupling (CC) for unidirectional wave and coherent perfect absorption (CPA) for bidirectional waves are obtained analytically for this system. The energy points at which total absorption occurs are shown to be the spectral singular points for the time reversed system. The possible energies at which CC occurs for left and right incidence are different. We further obtain periodic intervals with increasing periodicity of energy for CC and CPA to occur in this system. -- Highlights: •Energy ranges for CC and CPA are obtained explicitly for complex WS potential. •Analytical conditions for CC and CPA for PT symmetric WS potential are obtained. •Conditions for left and right CC are shown to be different. •Conditions for CC and CPA are shown to be that of SS for the time reversed system. •Our model shows the great flexibility of frequencies for CC and CPA.

  7. Using global sensitivity analysis to understand higher order interactions in complex models: an application of GSA on the Revised Universal Soil Loss Equation (RUSLE) to quantify model sensitivity and implications for ecosystem services management in Costa Rica

    NASA Astrophysics Data System (ADS)

    Fremier, A. K.; Estrada Carmona, N.; Harper, E.; DeClerck, F.

    2011-12-01

    Appropriate application of complex models to estimate system behavior requires understanding the influence of model structure and parameter estimates on model output. To date, most researchers perform local sensitivity analyses, rather than global, because of computational time and quantity of data produced. Local sensitivity analyses are limited in quantifying the higher order interactions among parameters, which could lead to incomplete analysis of model behavior. To address this concern, we performed a GSA on a commonly applied equation for soil loss - the Revised Universal Soil Loss Equation. USLE is an empirical model built on plot-scale data from the USA and the Revised version (RUSLE) includes improved equations for wider conditions, with 25 parameters grouped into six factors to estimate long-term plot and watershed scale soil loss. Despite RUSLE's widespread application, a complete sensitivity analysis has yet to be performed. In this research, we applied a GSA to plot and watershed scale data from the US and Costa Rica to parameterize the RUSLE in an effort to understand the relative importance of model factors and parameters across wide environmental space. We analyzed the GSA results using Random Forest, a statistical approach to evaluate parameter importance accounting for the higher order interactions, and used Classification and Regression Trees to show the dominant trends in complex interactions. In all GSA calculations the management of cover crops (C factor) ranks the highest among factors (compared to rain-runoff erosivity, topography, support practices, and soil erodibility). This is counter to previous sensitivity analyses where the topographic factor was determined to be the most important. The GSA finding is consistent across multiple model runs, including data from the US, Costa Rica, and a synthetic dataset of the widest theoretical space. The three most important parameters were: Mass density of live and dead roots found in the upper inch

  8. Detection of the 2175 Å Dust Feature in Mg II Absorption Systems

    NASA Astrophysics Data System (ADS)

    Malhotra, Sangeeta

    1997-10-01

    The broad absorption bump at 2175 Å due to dust, which is ubiquitous in the Galaxy and is seen in the Magellanic clouds, is also seen in a composite spectrum of Mg II absorbers. The composite absorber spectrum is obtained by taking the geometric mean of 92 quasar spectra after aligning them in the rest frame of 96 absorbers. By aligning the spectra according to absorber redshifts, we reinforce the spectral features of the absorbers and smooth over possible bumps and wiggles in the emission spectra as well as small features in the flat-fielding of the spectra. The width of the observed absorption feature is 200-300 Å (FWHM), or 0.4-0.6 μm-1, and the central wavelength is 2240 Å. These are somewhat different from the central wavelength of 2176 Å and FWHM = 0.8-1.25 μm-1 found in the Galaxy. Simulations show that this discrepancy between the properties of the 2175 Å feature in Mg II absorbers and the Galactic interstellar medium can be mostly explained by the different methods used to measure them.

  9. On the cosmic evolution of Fe/Mg in QSO absorption line systems

    NASA Astrophysics Data System (ADS)

    Dey, Arjun; Torrey, Paul; Rubin, Kate H. R.; Zhu, Guangtun Ben; Suresh, Joshua

    2015-08-01

    We investigate the variation of the ratio of the equivalent widths of the Fe II λ2600 line to the Mg II λλ2796, 2803 doublet as a function of redshift in a large sample of absorption lines drawn from the Johns Hopkins University - Sloan Digital Sky Survey Absorption Line Catalog. We find that despite large scatter, the observed ratio shows a trend where the equivalent width ratio R≡ W_{Fe II}/W_{Mg II} decreases monotonically with increasing redshift z over the range 0.55 ≤ z ≤ 1.90. Selecting the subset of absorbers where the signal-to-noise ratio of the Mg II equivalent width W_{Mg II} is ≥ 3 and modelling the equivalent width ratio distribution as a Gaussian, we find that the mean of the Gaussian distribution varies as R∝ (-0.045± 0.005)z. We discuss various possible reasons for the trend. A monotonic trend in the Fe/Mg abundance ratio is predicted by a simple model where the abundances of Mg and Fe in the absorbing clouds are assumed to be the result of supernova (SN) ejecta and where the cosmic evolution in the SNIa and core-collapse SN rates is related to the cosmic star formation rate. If the trend in R reflects the evolution in the abundances, then it is consistent with the predictions of the simple model.

  10. Performance evaluation of an active solar cooling system utilizing low cost plastic collectors and an evaporatively-cooled absorption chiller

    NASA Astrophysics Data System (ADS)

    Lof, G. O.; Westhoff, M. A.; Karaki, S.

    1984-02-01

    During the summer of 1982, air conditioning in Solar House 3 at Colorado State University was provided by an evaporatively-cooled absorption chiller. The single-effect lithium bromide chiller is an experimental three-ton unit from which heat is rejected by direct evaporative cooling of the condenser and absorber walls, thereby eliminating the need for a separate cooling tower. Domestic hot water was also provided by use of a double-walled heat exchanger and 80-gal hot water tank. A schematic of the system is given. Objectives of the project were: (1) evaluation of system performance over the course of one cooling season in Fort Collins, Colorado; (2) optimization of system operation and control; (3) development of a TRNSYS compatible model of the chiller; and (4) determination of cooling system performance in several U.S. climates by use of the model.

  11. A system coefficient approach for quantitative assessment of the solvent effects on membrane absorption from chemical mixtures.

    PubMed

    Xia, X R; Baynes, R E; Monteiro-Riviere, N A; Riviere, J E

    2007-01-01

    A system coefficient approach is proposed for quantitative assessment of the solvent effects on membrane absorption from chemical mixtures. The complicated molecular interactions are dissected into basic molecular interaction forces via Abraham's linear solvation energy relationship (LSER). The molecular interaction strengths of a chemical are represented by a set of solute descriptors, while those of a membrane/chemical mixture system are represented by a set of system coefficients. The system coefficients can be determined by using a set of probe compounds with known solute descriptors. Polydimethylsiloxane (PDMS) membrane-coated fibres and 32 probe compounds were used to demonstrate the proposed approach. When a solvent was added into the chemical mixture, the system coefficients were altered and detected by the system coefficient approach. The system coefficients of the PDMS/water system were (0.09, 0.49, -1.11, -2.36, -3.78, 3.50). When 25% ethanol was added into the PDMS/water system, the system coefficients were altered significantly (0.38, 0.41, -1.18, -2.07, -3.40, 2.81); and the solvent effect was quantitatively described by the changes in the system coefficients (0.29, -0.08, -0.07, 0.29, 0.38, -0.69). The LSER model adequately described the experimental data with a correlation coefficient (r(2)) of 0.995 and F-value of 1056 with p-value less than 0.0001.

  12. Optical systems modeling and experimental realization of pump and probe technique: investigation of nonlinear absorption in colloidal quantum dots

    NASA Astrophysics Data System (ADS)

    Smirnov, A.; Golinskaya, A.; Ezhova, K.; Kozlova, M.; Dneprovskii, V.

    2016-04-01

    Two optical systems modeling of laser and broadband radiation focusing, that is necessary for realization of the pump and probe method, was carried out in this work. Modeling was utilized to construct experimental setup for transmission spectra measuring of studied sample by probe nanosecond broadband radiation (coumarin photoluminescence) depending on the intensity of the nanosecond laser pump pulses. The saturation effect of absorption and the induced charge Stark-effect coexistence and predominate issue of these effects are determined by power of optical excitation. In dependence of tuning of excitation radiation frequency from basic exciton transition frequency nonlinear effects in colloidal CdSe/ZnS quantum dots has been investigated.

  13. Absorption Coefficients of the Methane-Nitrogen Binary Ice System: Implications for Pluto

    NASA Astrophysics Data System (ADS)

    Protopapa, Silvia; Grundy, W.; Tegler, S.; Bergonio, J.; Boehnhardt, H.; Barrera, L.

    2013-10-01

    Near infrared spectroscopic measurements of Pluto display methane (CH4) ice absorption bands shifted toward shorter wavelengths compared to the central wavelengths of pure CH4 obtained in the laboratory. This shift, described by Schmitt and Quirico (1992), occurs when CH4 is dissolved at low concentrations in a matrix of solid N2, and the magnitude of the shift varies from one CH4 band to another. This is the main argument behind the modeling analysis of Pluto’s spectra available in literature, employing pure CH4 and CH4 diluted at low concentrations in N2. However, the nitrogen-methane binary phase diagram generated from X-ray diffraction studies by Prokhvatilov & Yantsevich (1983) indicates that at temperatures relevant to the surfaces of icy dwarf planets, like Pluto, two phases contribute to the absorptions: methane ice saturated with nitrogen and nitrogen ice saturated with methane. No optical constants are available so far for the latter component, limiting this way the knowledge of the methane-nitrogen mixing ratio across and into the surface of Pluto and other dwarf planets. New infrared absorption coefficient spectra of CH4-I diluted in β-N2 and β-N2 diluted in CH4-I were measured at temperatures between 40 and 90 K, in the wavelength range 0.8-2.5 μm at different mixing ratios. The spectra were derived from transmission measurements of crystals grown from the liquid phase in closed cells. In particular, a systematic study of the changes in CH4:N2 mixtures spectral behavior with mixing ratio is presented for the first time, in order to understand whether the peak frequencies of the CH4-ice bands correlate with the amount of N2-ice. We report a linear trend of the blueshifts of the CH4-ice bands vs CH4 abundance. This trend varies from band to band, while it is fairly constant with temperature. These data are applied to interpret unpublished high dispersion H and K bands spectra of Pluto acquired with the NACO instrument at the ESO VLT on 27 June 2008

  14. A Ground-Based Profiling Differential Absorption LIDAR System for Measuring CO2 in the Planetary Boundary Layer

    NASA Technical Reports Server (NTRS)

    Andrews, Arlyn E.; Burris, John F.; Abshire, James B.; Krainak, Michael A.; Riris, Haris; Sun, Xiao-Li; Collatz, G. James

    2002-01-01

    Ground-based LIDAR observations can potentially provide continuous profiles of CO2 through the planetary boundary layer and into the free troposphere. We will present initial atmospheric measurements from a prototype system that is based on components developed by the telecommunications industry. Preliminary measurements and instrument performance calculations indicate that an optimized differential absorption LIDAR (DIAL) system will be capable of providing continuous hourly averaged profiles with 250m vertical resolution and better than 1 ppm precision at 1 km. Precision increases (decreases) at lower (higher) altitudes and is directly proportional to altitude resolution and acquisition time. Thus, precision can be improved if temporal or vertical resolution is sacrificed. Our approach measures absorption by CO2 of pulsed laser light at 1.6 microns backscattered from atmospheric aerosols. Aerosol concentrations in the planetary boundary layer are relatively high and are expected to provide adequate signal returns for the desired resolution. The long-term goal of the project is to develop a rugged, autonomous system using only commercially available components that can be replicated inexpensively for deployment in a monitoring network.

  15. Using Observations of Deep Convective Systems to Constrain Atmospheric Column Absorption of Solar Radiation in the Optically Thick Limit

    NASA Technical Reports Server (NTRS)

    Dong, Xiquan; Wielicki, Bruce A.; Xi, Baike; Hu, Yongxiang; Mace, Gerald G.; Benson, Sally; Rose, Fred; Kato, Seiji; Charlock, Thomas; Minnis, Patrick

    2008-01-01

    Atmospheric column absorption of solar radiation A(sub col) is a fundamental part of the Earth's energy cycle but is an extremely difficult quantity to measure directly. To investigate A(sub col), we have collocated satellite-surface observations for the optically thick Deep Convective Systems (DCS) at the Department of Energy Atmosphere Radiation Measurement (ARM) Tropical Western Pacific (TWP) and Southern Great Plains (SGP) sites during the period of March 2000 December 2004. The surface data were averaged over a 2-h interval centered at the time of the satellite overpass, and the satellite data were averaged within a 1 deg X 1 deg area centered on the ARM sites. In the DCS, cloud particle size is important for top-of-atmosphere (TOA) albedo and A(sub col) although the surface absorption is independent of cloud particle size. In this study, we find that the A(sub col) in the tropics is approximately 0.011 more than that in the middle latitudes. This difference, however, disappears, i.e., the A(sub col) values at both regions converge to the same value (approximately 0.27 of the total incoming solar radiation) in the optically thick limit (tau greater than 80). Comparing the observations with the NASA Langley modified Fu_Liou 2-stream radiative transfer model for optically thick cases, the difference between observed and model-calculated surface absorption, on average, is less than 0.01, but the model-calculated TOA albedo and A(sub col) differ by 0.01 to 0.04, depending primarily on the cloud particle size observation used. The model versus observation discrepancies found are smaller than many previous studies and are just within the estimated error bounds. We did not find evidence for a large cloud absorption anomaly for the optically thick limit of extensive ice cloud layers. A more modest cloud absorption difference of 0.01 to 0.04 cannot yet be ruled out. The remaining uncertainty could be reduced with additional cases, and by reducing the current

  16. Systemic Absorption of Catechins after Intraruminal or Intraduodenal Application of a Green Tea Extract in Cows

    PubMed Central

    Wein, Silvia; Beyer, Birgit; Gohlke, Annika; Blank, Ralf; Metges, Cornelia C.; Wolffram, Siegfried

    2016-01-01

    Green tea catechins have various potential health benefits in humans including anti-inflammatory, anti-oxidative and hepato-protective effects. If present in the circulation, they might have similar effects in ruminants, which are exposed to oxidative stress and fatty liver disease such as dairy cows during the periparturient phase. However, the bioavailability of a substance is a prerequisite for any post absorptive effect in vivo. This study aimed to investigate the appearance of catechins from a green tea extract (GTE) in cattle plasma after intraruminal and intraduodenal administration because absorption is of major importance regarding the bioavailability of catechins. The studies were performed in 5 rumen-fistulated non-lactating heifers and 6 duodenally fistulated lactating dairy cows, respectively, equipped with indwelling catheters placed in a jugular vein. The GTE was applied intraruminally (10 and 50 mg/kg BW, heifers) or duodenally (10, 20 and 30 mg/kg BW, dairy cows) in a cross‐over design with a 2 d washout period between different dosages. Blood samples were drawn following the GTE administration at various pre-defined time intervals. The concentration of the major GTE catechins (gallocatechin, epigallocatechin, catechin, epicatechin, epigallocatechin-gallate, epicatechin-gallate) in plasma samples were analysed by HPLC with electrochemical detection. Irrespective of the dose, almost none of the catechins originally contained in the GTE were detected in plasma samples after intraruminal application. In contrast, intraduodenal administration of GTE resulted in increased plasma concentrations of epicatechin, epigallocatechin, epigallocatechin gallate in a dose‐dependent manner. Thus, we can conclude that intraruminally or orally administered catechins are intensively metabolized by ruminal microorganisms. PMID:27427946

  17. Systemic Absorption of Catechins after Intraruminal or Intraduodenal Application of a Green Tea Extract in Cows.

    PubMed

    Wein, Silvia; Beyer, Birgit; Gohlke, Annika; Blank, Ralf; Metges, Cornelia C; Wolffram, Siegfried

    2016-01-01

    Green tea catechins have various potential health benefits in humans including anti-inflammatory, anti-oxidative and hepato-protective effects. If present in the circulation, they might have similar effects in ruminants, which are exposed to oxidative stress and fatty liver disease such as dairy cows during the periparturient phase. However, the bioavailability of a substance is a prerequisite for any post absorptive effect in vivo. This study aimed to investigate the appearance of catechins from a green tea extract (GTE) in cattle plasma after intraruminal and intraduodenal administration because absorption is of major importance regarding the bioavailability of catechins. The studies were performed in 5 rumen-fistulated non-lactating heifers and 6 duodenally fistulated lactating dairy cows, respectively, equipped with indwelling catheters placed in a jugular vein. The GTE was applied intraruminally (10 and 50 mg/kg BW, heifers) or duodenally (10, 20 and 30 mg/kg BW, dairy cows) in a cross-over design with a 2 d washout period between different dosages. Blood samples were drawn following the GTE administration at various pre-defined time intervals. The concentration of the major GTE catechins (gallocatechin, epigallocatechin, catechin, epicatechin, epigallocatechin-gallate, epicatechin-gallate) in plasma samples were analysed by HPLC with electrochemical detection. Irrespective of the dose, almost none of the catechins originally contained in the GTE were detected in plasma samples after intraruminal application. In contrast, intraduodenal administration of GTE resulted in increased plasma concentrations of epicatechin, epigallocatechin, epigallocatechin gallate in a dose-dependent manner. Thus, we can conclude that intraruminally or orally administered catechins are intensively metabolized by ruminal microorganisms. PMID:27427946

  18. Absorption-ablation-excitation mechanism of laser-cluster interactions in a nanoaerosol system.

    PubMed

    Ren, Yihua; Li, Shuiqing; Zhang, Yiyang; Tse, Stephen D; Long, Marshall B

    2015-03-01

    The absorption-ablation-excitation mechanism in laser-cluster interactions is investigated by measuring Rayleigh scattering of aerosol clusters along with atomic emission from phase-selective laser-induced breakdown spectroscopy. For 532 nm excitation, as the laser intensity increases beyond 0.16  GW/cm^{2}, the scattering cross section of TiO_{2} clusters begins to decrease, concurrent with the onset of atomic emission of Ti, indicating a scattering-to-ablation transition and the formation of nanoplasmas. With 1064 nm laser excitation, the atomic emissions are more than one order of magnitude weaker than that at 532 nm, indicating that the thermal effect is not the main mechanism. To better clarify the process, time-resolved measurements of scattering signals are examined for different excitation laser intensities. For increasing laser intensity, the cross section of clusters decreases during a single pulse, evincing the shorter ablation delay time and larger ratios of ablation clusters. Assessment of the electron energy distribution during the ablation process is conducted by nondimensionalizing the Fokker-Planck equation, with analogous Strouhal Sl_{E}, Peclet Pe_{E}, and Damköhler Da_{E} numbers defined to characterize the laser-induced aerothermochemical environment. For conditions where Sl_{E}≫1, Pe_{E}≫1, and Da_{E}≪1, the electrons are excited to the conduction band by two-photon absorption, then relax to the bottom of the conduction band by electron energy loss to the lattice, and finally serve as the energy transfer media between laser field and lattice. The relationship between delay time and excitation intensity is well correlated by this simplified model with quasisteady assumption.

  19. Absorption-Ablation-Excitation Mechanism of Laser-Cluster Interactions in a Nanoaerosol System

    NASA Astrophysics Data System (ADS)

    Ren, Yihua; Li, Shuiqing; Zhang, Yiyang; Tse, Stephen D.; Long, Marshall B.

    2015-03-01

    The absorption-ablation-excitation mechanism in laser-cluster interactions is investigated by measuring Rayleigh scattering of aerosol clusters along with atomic emission from phase-selective laser-induced breakdown spectroscopy. For 532 nm excitation, as the laser intensity increases beyond 0.16 GW /cm2 , the scattering cross section of TiO2 clusters begins to decrease, concurrent with the onset of atomic emission of Ti, indicating a scattering-to-ablation transition and the formation of nanoplasmas. With 1064 nm laser excitation, the atomic emissions are more than one order of magnitude weaker than that at 532 nm, indicating that the thermal effect is not the main mechanism. To better clarify the process, time-resolved measurements of scattering signals are examined for different excitation laser intensities. For increasing laser intensity, the cross section of clusters decreases during a single pulse, evincing the shorter ablation delay time and larger ratios of ablation clusters. Assessment of the electron energy distribution during the ablation process is conducted by nondimensionalizing the Fokker-Planck equation, with analogous Strouhal SlE , Peclet PeE , and Damköhler DaE numbers defined to characterize the laser-induced aerothermochemical environment. For conditions where SlE≫1 , PeE≫1 , and DaE≪1 , the electrons are excited to the conduction band by two-photon absorption, then relax to the bottom of the conduction band by electron energy loss to the lattice, and finally serve as the energy transfer media between laser field and lattice. The relationship between delay time and excitation intensity is well correlated by this simplified model with quasisteady assumption.

  20. Absorption-ablation-excitation mechanism of laser-cluster interactions in a nanoaerosol system.

    PubMed

    Ren, Yihua; Li, Shuiqing; Zhang, Yiyang; Tse, Stephen D; Long, Marshall B

    2015-03-01

    The absorption-ablation-excitation mechanism in laser-cluster interactions is investigated by measuring Rayleigh scattering of aerosol clusters along with atomic emission from phase-selective laser-induced breakdown spectroscopy. For 532 nm excitation, as the laser intensity increases beyond 0.16  GW/cm^{2}, the scattering cross section of TiO_{2} clusters begins to decrease, concurrent with the onset of atomic emission of Ti, indicating a scattering-to-ablation transition and the formation of nanoplasmas. With 1064 nm laser excitation, the atomic emissions are more than one order of magnitude weaker than that at 532 nm, indicating that the thermal effect is not the main mechanism. To better clarify the process, time-resolved measurements of scattering signals are examined for different excitation laser intensities. For increasing laser intensity, the cross section of clusters decreases during a single pulse, evincing the shorter ablation delay time and larger ratios of ablation clusters. Assessment of the electron energy distribution during the ablation process is conducted by nondimensionalizing the Fokker-Planck equation, with analogous Strouhal Sl_{E}, Peclet Pe_{E}, and Damköhler Da_{E} numbers defined to characterize the laser-induced aerothermochemical environment. For conditions where Sl_{E}≫1, Pe_{E}≫1, and Da_{E}≪1, the electrons are excited to the conduction band by two-photon absorption, then relax to the bottom of the conduction band by electron energy loss to the lattice, and finally serve as the energy transfer media between laser field and lattice. The relationship between delay time and excitation intensity is well correlated by this simplified model with quasisteady assumption. PMID:25793812

  1. Quantum phase diagram and time-of-flight absorption pictures of an ultracold Bose system in a square optical superlattice

    NASA Astrophysics Data System (ADS)

    Wei, Fan; Zhang, Jun; Jiang, Ying

    2016-01-01

    In this letter, by the use of the generalized effective potential theory, with the help of the process chain approach under the framework of the Kato formulation of the perturbation expansion, we calculate out the quantum phase diagram up to the 8th order for an ultracold Bose system in a square optical superlattice. Based on these perturbative data, with the help of the linear fit extrapolation technique, more accurate results are obtained, which are in excellent agreement with recent Monte Carlo numerical results. Moreover, by employing the generalized re-summed Green's function method and cumulant expansion, the momentum distribution function of the system is also calculated analytically and the time-of-flight absorption pictures of the system are plotted.

  2. A census of quasar-intrinsic absorption in the Hubble Space Telescope archive: systems from high-resolution echelle spectra

    NASA Astrophysics Data System (ADS)

    Ganguly, Rajib; Lynch, Ryan S.; Charlton, Jane C.; Eracleous, Michael; Tripp, Todd M.; Palma, Christopher; Sembach, Kenneth R.; Misawa, Toru; Masiero, Joseph R.; Milutinovic, Nikola; Lackey, Benjamin D.; Jones, Therese M.

    2013-10-01

    We present a census of zabs ≲ 2 intrinsic (those showing partial coverage) and associated (zabs ˜ zem) quasar absorption-line systems detected in the Hubble Space Telescope archive of Space Telescope Imaging Spectrograph echelle spectra. This work complements the Misawa et al. survey of 2 < zem < 4 quasars that selects systems using similar techniques. We confirm the existence of so-called strong N V intrinsic systems (where the equivalent width of H I Lyα is small compared to N V λ1238) presented in that work, but find no convincing cases of `strong C IV' intrinsic systems at low redshift/luminosity. Moreover, we also report on the existence of `strong O VI' systems. From a comparison of partial coverage results as a function of ion, we conclude that systems selected by the N V ion have the highest probability of being intrinsic. By contrast, the C IV and O VI ions are poor selectors. Of the 30 O VI systems tested, only two of the systems in the spectrum on 3C 351 show convincing evidence for partial coverage. However, there is an ˜3σ excess in the number of absorbers near the quasar redshift (|Δv| ≤ 5000 km s-1) over absorbers at large redshift differences. In at least two cases, the associated O VI systems are known not to arise close to the accretion disc of the quasar.

  3. 41 CFR 102-37.100 - What factors will GSA consider in allocating surplus property among SASPs?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-generated property to be allocated through a SASP for donation to a specific service educational activity. (c) Need and usability of property, as reflected by requests from SASPs. GSA will also give special... property among the SASPs on a fair and equitable basis using the following factors: (a) Extraordinary...

  4. 41 CFR 102-37.100 - What factors will GSA consider in allocating surplus property among SASPs?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...-generated property to be allocated through a SASP for donation to a specific service educational activity. (c) Need and usability of property, as reflected by requests from SASPs. GSA will also give special... property among the SASPs on a fair and equitable basis using the following factors: (a) Extraordinary...

  5. 41 CFR 102-37.100 - What factors will GSA consider in allocating surplus property among SASPs?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...-generated property to be allocated through a SASP for donation to a specific service educational activity. (c) Need and usability of property, as reflected by requests from SASPs. GSA will also give special... property among the SASPs on a fair and equitable basis using the following factors: (a) Extraordinary...

  6. Hidden drivers of low-dose pharmaceutical pollutant mixtures revealed by the novel GSA-QHTS screening method

    PubMed Central

    Rodea-Palomares, Ismael; Gonzalez-Pleiter, Miguel; Gonzalo, Soledad; Rosal, Roberto; Leganes, Francisco; Sabater, Sergi; Casellas, Maria; Muñoz-Carpena, Rafael; Fernández-Piñas, Francisca

    2016-01-01

    The ecological impacts of emerging pollutants such as pharmaceuticals are not well understood. The lack of experimental approaches for the identification of pollutant effects in realistic settings (that is, low doses, complex mixtures, and variable environmental conditions) supports the widespread perception that these effects are often unpredictable. To address this, we developed a novel screening method (GSA-QHTS) that couples the computational power of global sensitivity analysis (GSA) with the experimental efficiency of quantitative high-throughput screening (QHTS). We present a case study where GSA-QHTS allowed for the identification of the main pharmaceutical pollutants (and their interactions), driving biological effects of low-dose complex mixtures at the microbial population level. The QHTS experiments involved the integrated analysis of nearly 2700 observations from an array of 180 unique low-dose mixtures, representing the most complex and data-rich experimental mixture effect assessment of main pharmaceutical pollutants to date. An ecological scaling-up experiment confirmed that this subset of pollutants also affects typical freshwater microbial community assemblages. Contrary to our expectations and challenging established scientific opinion, the bioactivity of the mixtures was not predicted by the null mixture models, and the main drivers that were identified by GSA-QHTS were overlooked by the current effect assessment scheme. Our results suggest that current chemical effect assessment methods overlook a substantial number of ecologically dangerous chemical pollutants and introduce a new operational framework for their systematic identification. PMID:27617294

  7. Hidden drivers of low-dose pharmaceutical pollutant mixtures revealed by the novel GSA-QHTS screening method.

    PubMed

    Rodea-Palomares, Ismael; Gonzalez-Pleiter, Miguel; Gonzalo, Soledad; Rosal, Roberto; Leganes, Francisco; Sabater, Sergi; Casellas, Maria; Muñoz-Carpena, Rafael; Fernández-Piñas, Francisca

    2016-09-01

    The ecological impacts of emerging pollutants such as pharmaceuticals are not well understood. The lack of experimental approaches for the identification of pollutant effects in realistic settings (that is, low doses, complex mixtures, and variable environmental conditions) supports the widespread perception that these effects are often unpredictable. To address this, we developed a novel screening method (GSA-QHTS) that couples the computational power of global sensitivity analysis (GSA) with the experimental efficiency of quantitative high-throughput screening (QHTS). We present a case study where GSA-QHTS allowed for the identification of the main pharmaceutical pollutants (and their interactions), driving biological effects of low-dose complex mixtures at the microbial population level. The QHTS experiments involved the integrated analysis of nearly 2700 observations from an array of 180 unique low-dose mixtures, representing the most complex and data-rich experimental mixture effect assessment of main pharmaceutical pollutants to date. An ecological scaling-up experiment confirmed that this subset of pollutants also affects typical freshwater microbial community assemblages. Contrary to our expectations and challenging established scientific opinion, the bioactivity of the mixtures was not predicted by the null mixture models, and the main drivers that were identified by GSA-QHTS were overlooked by the current effect assessment scheme. Our results suggest that current chemical effect assessment methods overlook a substantial number of ecologically dangerous chemical pollutants and introduce a new operational framework for their systematic identification.

  8. 75 FR 6032 - Property Obtained Through the Use of Charge Cards; Notice of GSA Bulletin FMR B-25

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-05

    ... ADMINISTRATION Property Obtained Through the Use of Charge Cards; Notice of GSA Bulletin FMR B-25 AGENCY: Office... guidance to all agencies acquiring property using the government charge card. DATES: The bulletin announced.... SUPPLEMENTARY INFORMATION: A. Background Although charge cards provide a great benefit in...

  9. Hidden drivers of low-dose pharmaceutical pollutant mixtures revealed by the novel GSA-QHTS screening method

    PubMed Central

    Rodea-Palomares, Ismael; Gonzalez-Pleiter, Miguel; Gonzalo, Soledad; Rosal, Roberto; Leganes, Francisco; Sabater, Sergi; Casellas, Maria; Muñoz-Carpena, Rafael; Fernández-Piñas, Francisca

    2016-01-01

    The ecological impacts of emerging pollutants such as pharmaceuticals are not well understood. The lack of experimental approaches for the identification of pollutant effects in realistic settings (that is, low doses, complex mixtures, and variable environmental conditions) supports the widespread perception that these effects are often unpredictable. To address this, we developed a novel screening method (GSA-QHTS) that couples the computational power of global sensitivity analysis (GSA) with the experimental efficiency of quantitative high-throughput screening (QHTS). We present a case study where GSA-QHTS allowed for the identification of the main pharmaceutical pollutants (and their interactions), driving biological effects of low-dose complex mixtures at the microbial population level. The QHTS experiments involved the integrated analysis of nearly 2700 observations from an array of 180 unique low-dose mixtures, representing the most complex and data-rich experimental mixture effect assessment of main pharmaceutical pollutants to date. An ecological scaling-up experiment confirmed that this subset of pollutants also affects typical freshwater microbial community assemblages. Contrary to our expectations and challenging established scientific opinion, the bioactivity of the mixtures was not predicted by the null mixture models, and the main drivers that were identified by GSA-QHTS were overlooked by the current effect assessment scheme. Our results suggest that current chemical effect assessment methods overlook a substantial number of ecologically dangerous chemical pollutants and introduce a new operational framework for their systematic identification.

  10. 41 CFR 102-71.5 - What is the scope and philosophy of the General Services Administration's (GSA) real property...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false What is the scope and philosophy of the General Services Administration's (GSA) real property policies? 102-71.5 Section 102-71.5...) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 71-GENERAL § 102-71.5 What is the scope and philosophy of...

  11. 41 CFR 102-71.5 - What is the scope and philosophy of the General Services Administration's (GSA) real property...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false What is the scope and philosophy of the General Services Administration's (GSA) real property policies? 102-71.5 Section 102-71.5...) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 71-GENERAL § 102-71.5 What is the scope and philosophy of...

  12. 41 CFR 102-71.5 - What is the scope and philosophy of the General Services Administration's (GSA) real property...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What is the scope and philosophy of the General Services Administration's (GSA) real property policies? 102-71.5 Section 102-71.5...) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 71-GENERAL § 102-71.5 What is the scope and philosophy of...

  13. 41 CFR 102-75.945 - What is GSA's policy concerning the physical care, handling, protection, and maintenance of...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... related personal property? 102-75.945 Section 102-75.945 Public Contracts and Property Management Federal... related personal property? GSA's policy is to— (a) Manage excess and surplus real property, including related personal property, by providing only those minimum services necessary to preserve the...

  14. 41 CFR 102-36.305 - May we abandon or destroy excess personal property without reporting it to GSA?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... destroy excess personal property without reporting it to GSA? 102-36.305 Section 102-36.305 Public... MANAGEMENT REGULATION PERSONAL PROPERTY 36-DISPOSITION OF EXCESS PERSONAL PROPERTY Disposition of Excess Personal Property Abandonment/destruction § 102-36.305 May we abandon or destroy excess personal...

  15. 41 CFR 102-118.335 - What does the GSA Audit Division consider when verifying an agency prepayment audit program?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What does the GSA Audit Division consider when verifying an agency prepayment audit program? 102-118.335 Section 102-118.335 Public... positive improvements, as well as adherence to the guidelines listed in this part....

  16. 5 CFR 6701.104 - Prohibited purchases of real estate by certain GSA employees involved in the acquisition or...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Prohibited purchases of real estate by certain GSA employees involved in the acquisition or disposal of real estate. 6701.104 Section 6701.104 Administrative Personnel GENERAL SERVICES ADMINISTRATION SUPPLEMENTAL STANDARDS OF ETHICAL CONDUCT FOR EMPLOYEES OF THE GENERAL...

  17. 41 CFR 101-26.4902-2891 - GSA Form 2891: Instructions to Users of Federal Supply Schedules.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: Instructions to Users of Federal Supply Schedules. 101-26.4902-2891 Section 101-26.4902-2891 Public Contracts....4902-2891 GSA Form 2891: Instructions to Users of Federal Supply Schedules. Note: The form illustrated... Register or the Code of Federal Regulations....

  18. 41 CFR 101-26.104 - End-of-year submission of requisitions for action by GSA.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... required to reflect the applicable appropriation or fiscal year funds to be charged. The fund code entry on... to be chargeable to appropriations expiring the last day of the fiscal year are submitted in sufficient time for GSA to consummate the necessary action before the end of the fiscal year....

  19. 41 CFR 102-118.260 - Must my agency send all quotations, tenders, or contracts with a TSP to GSA?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Regulation parts 102-117 and 102-118 (41 CFR parts 102-117 and 102-118), and the TSP(s) hold(s) the required... execution to—General Services Administration, Transportation Audit Division (QMCA), Crystal Plaza 4, Room 300, 2200 Crystal Drive, Arlington, VA 22202, www.gsa.gov/transaudits. (b) Tenders must be...

  20. 41 CFR 102-118.260 - Must my agency send all quotations, tenders, or contracts with a TSP to GSA?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Regulation parts 102-117 and 102-118 (41 CFR parts 102-117 and 102-118), and the TSP(s) hold(s) the required... execution to—General Services Administration, Transportation Audit Division (QMCA), Crystal Plaza 4, Room 300, 2200 Crystal Drive, Arlington, VA 22202, www.gsa.gov/transaudits. (b) Tenders must be...

  1. 41 CFR 102-118.260 - Must my agency send all quotations, tenders, or contracts with a TSP to GSA?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Regulation parts 102-117 and 102-118 (41 CFR parts 102-117 and 102-118), and the TSP(s) hold(s) the required... execution to—General Services Administration, Transportation Audit Division (QMCA), Crystal Plaza 4, Room 300, 2200 Crystal Drive, Arlington, VA 22202, www.gsa.gov/transaudits. (b) Tenders must be...

  2. 41 CFR 102-118.260 - Must my agency send all quotations, tenders, or contracts with a TSP to GSA?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Regulation parts 102-117 and 102-118 (41 CFR parts 102-117 and 102-118), and the TSP(s) hold(s) the required... execution to—General Services Administration, Transportation Audit Division (QMCA), Crystal Plaza 4, Room 300, 2200 Crystal Drive, Arlington, VA 22202, www.gsa.gov/transaudits. (b) Tenders must be...

  3. 41 CFR 102-192.90 - What must we include in our annual mail management report to GSA?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... annual mail management report to GSA? Your annual report must— (a) Identify your agency mail manager; in addition you must promptly report the name of the agency mail manager whenever there is a change of the... accomplishments and plans to improve the economy and efficiency of mail operations in the current and future...

  4. 41 CFR 102-192.90 - What must we include in our annual mail management report to GSA?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... annual mail management report to GSA? Your annual report must— (a) Identify your agency mail manager; in addition you must promptly report the name of the agency mail manager whenever there is a change of the... accomplishments and plans to improve the economy and efficiency of mail operations in the current and future...

  5. 41 CFR 102-118.260 - Must my agency send all quotations, tenders, or contracts with a TSP to GSA?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Regulation parts 102-117 and 102-118 (41 CFR parts 102-117 and 102-118), and the TSP(s) hold(s) the required... execution to—General Services Administration, Transportation Audit Division (QMCA), Crystal Plaza 4, Room 300, 2200 Crystal Drive, Arlington, VA 22202, www.gsa.gov/transaudits. (b) Tenders must be...

  6. 41 CFR 102-71.5 - What is the scope and philosophy of the General Services Administration's (GSA) real property...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What is the scope and philosophy of the General Services Administration's (GSA) real property policies? 102-71.5 Section 102-71.5...) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 71-GENERAL § 102-71.5 What is the scope and philosophy of...

  7. 41 CFR 102-71.5 - What is the scope and philosophy of the General Services Administration's (GSA) real property...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What is the scope and philosophy of the General Services Administration's (GSA) real property policies? 102-71.5 Section 102-71.5...) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 71-GENERAL § 102-71.5 What is the scope and philosophy of...

  8. Hidden drivers of low-dose pharmaceutical pollutant mixtures revealed by the novel GSA-QHTS screening method.

    PubMed

    Rodea-Palomares, Ismael; Gonzalez-Pleiter, Miguel; Gonzalo, Soledad; Rosal, Roberto; Leganes, Francisco; Sabater, Sergi; Casellas, Maria; Muñoz-Carpena, Rafael; Fernández-Piñas, Francisca

    2016-09-01

    The ecological impacts of emerging pollutants such as pharmaceuticals are not well understood. The lack of experimental approaches for the identification of pollutant effects in realistic settings (that is, low doses, complex mixtures, and variable environmental conditions) supports the widespread perception that these effects are often unpredictable. To address this, we developed a novel screening method (GSA-QHTS) that couples the computational power of global sensitivity analysis (GSA) with the experimental efficiency of quantitative high-throughput screening (QHTS). We present a case study where GSA-QHTS allowed for the identification of the main pharmaceutical pollutants (and their interactions), driving biological effects of low-dose complex mixtures at the microbial population level. The QHTS experiments involved the integrated analysis of nearly 2700 observations from an array of 180 unique low-dose mixtures, representing the most complex and data-rich experimental mixture effect assessment of main pharmaceutical pollutants to date. An ecological scaling-up experiment confirmed that this subset of pollutants also affects typical freshwater microbial community assemblages. Contrary to our expectations and challenging established scientific opinion, the bioactivity of the mixtures was not predicted by the null mixture models, and the main drivers that were identified by GSA-QHTS were overlooked by the current effect assessment scheme. Our results suggest that current chemical effect assessment methods overlook a substantial number of ecologically dangerous chemical pollutants and introduce a new operational framework for their systematic identification. PMID:27617294

  9. Re-Assessing Green Building Performance: A Post Occupancy Evaluation of 22 GSA Buildings

    SciTech Connect

    Fowler, Kimberly M.; Rauch, Emily M.; Henderson, Jordan W.; Kora, Angela R.

    2010-06-01

    2nd report on the performance of GSA's sustainably designed buildings. The purpose of this study was to provide an overview of measured whole building performance as it compares to GSA and industry baselines. The PNNL research team found the data analysis illuminated strengths and weaknesses of individual buildings as well as the portfolio of buildings. This section includes summary data, observations that cross multiple performance metrics, discussion of lessons learned from this research, and opportunities for future research. The summary of annual data for each of the performance metrics is provided in Table 25. The data represent 1 year of measurements and are not associated with any specific design features or strategies. Where available, multiple years of data were examined and there were minimal significant differences between the years. Individually focused post occupancy evaluation (POEs) would allow for more detailed analysis of the buildings. Examining building performance over multiple years could potentially offer a useful diagnostic tool for identifying building operations that are in need of operational changes. Investigating what the connection is between the building performance and the design intent would offer potential design guidance and possible insight into building operation strategies. The 'aggregate operating cost' metric used in this study represents the costs that were available for developing a comparative industry baseline for office buildings. The costs include water utilities, energy utilities, general maintenance, grounds maintenance, waste and recycling, and janitorial costs. Three of the buildings that cost more than the baseline in Figure 45 have higher maintenance costs than the baseline, and one has higher energy costs. Given the volume of data collected and analyzed for this study, the inevitable request is for a simple answer with respect to sustainably designed building performance. As previously stated, compiling the

  10. Development of an in-situ structure/photo-absorption coincident measurement system for precise structure-optical property relationship research at SPring-8

    NASA Astrophysics Data System (ADS)

    Kim, Jungeun; Kato, Kenichi; Moritomo, Yutaka; Takata, Masaki

    2010-06-01

    We have developed the structure and optical property coincident measurement system equipped with the photo-absorption system to the Large Debye-Scherrer Camera at BL44B2 of the SPring-8. Both photo-absorption detecting systems, the Si pin-photo diode for a 532 nm CW laser and the absorption spectrum covered the range of UV-IR (200˜1400 nm) for a white beam, are adopted. In order to verify the coincident measurement system, the X-ray powder diffraction and photo-absorption with the cyanide complex were performed individually and simultaneously under the temperature changes. As a result, the coincident measurement system performed successfully the one-to-one corresponding measurement between X-ray diffraction and photo-absorption. In addition, the monitoring of the photo-absorption informed us the property change of the material for the measurement condition and the sample transformation by temperature, laser etc. as well as damage by high-brilliance synchrotron radiation X-ray beam.

  11. 76 FR 49484 - Privacy Act of 1974; Notice of New System of Records

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ... authentication to access Google Apps for Government implementation used by the GSA. Dated: July 26, 2011. Cheryl... system contains information needed to utilize two factor authentication to access Google Apps for... to access Google Apps for Government implementation used by the GSA. ROUTINE USES OF...

  12. 77 FR 63316 - Privacy Act of 1974; Notice of New System of Records

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-16

    ... application environment and the Google Apps for Government platform used by the GSA. Dated: October 4, 2012... Organization of Google Applications for Government and SalesForce.com for Government. SYSTEM LOCATION... part of GSA's implementation of Google Apps for Government and Salesforce.com for Government....

  13. First calibration measurements of an FTIR absorption spectroscopy system for liquid hydrogen isotopologues for the isotope separation system of fusion power plants

    SciTech Connect

    Groessle, R.; Beck, A.; Bornschein, B.; Fischer, S.; Kraus, A.; Mirz, S.; Rupp, S.

    2015-03-15

    Fusion facilities like ITER and DEMO will circulate huge amounts of deuterium and tritium in their fuel cycle with an estimated throughput of kg per hour. One important capability of these fuel cycles is to separate the hydrogen isotopologues (H{sub 2}, D{sub 2}, T{sub 2}, HD, HT, DT). For this purpose the Isotope Separation System (ISS), using cryogenic distillation, as part of the Tritium Enrichment Test Assembly (TRENTA) is under development at Tritium Laboratory Karlsruhe. Fourier transform infrared absorption spectroscopy (FTIR) has been selected to prove its capability for online monitoring of the tritium concentration in the liquid phase at the bottom of the distillation column of the ISS. The actual research-development work is focusing on the calibration of such a system. Two major issues are the identification of appropriate absorption lines and their dependence on the isotopic concentrations and composition. For this purpose the Tritium Absorption IR spectroscopy experiment has been set up as an extension of TRENTA. For calibration a Raman spectroscopy system is used. First measurements, with equilibrated mixtures of H{sub 2}, D{sub 2} and HD demonstrate that FTIR can be used for quantitative analysis of liquid hydro-gen isotopologues and reveal a nonlinear dependence of the integrated absorbance from the D{sub 2} concentration in the second vibrational branch of D{sub 2} FTIR spectra. (authors)

  14. Determination of water absorption and water holding capacities of different soil mixtures with MINIDRAIN system to enhance the plant growth

    NASA Astrophysics Data System (ADS)

    Sudan Acharya, Madhu; Rauchecker, Markus; Wu, Wei

    2014-05-01

    Soil water holding capacity is the amount of water that a given soil can hold against the force of gravity. Soil texture and organic matter are the key components that determine soil water holding capacity. Soils with smaller particle sizes, such as silt and clay have larger surface area can hold more water compared to sand which has large particle sizes which results in smaller surface area. A study report showed that 1% increase in soil humus will result in a 4% increase in stored soil water (Morris, 2004) and 1 part humus holds 4 parts of water (Wheeler and Ward, 1998). Therefore, the more humus that can be added to the soil, the greater the water holding capacity of the soil. As the level of organic matter increases in a soil, the water holding capacity also increases due to the affinity of organic matter for water. The water holding capacity of the soil is determined by the amount of water held in the soil sample vs. the dry weight of the sample. MINIDRAIN is a patented system made of geo-fabric (fleece) or combination of geosynthetics and humus. MINIDRAIN and vegetation nets developed by the company ÖKO-TEX (Linz, Austria) will improve the distribution of water and air in the soils, increase the growth of vegetation and reduce the soil erosion. Depending on the physical configuration, there are four different combinations of MINIDRAIN systems developed by ÖKO-TEX. a) Geotextile (fleece) strips of different sizes (e.g. 5x10x250 mm) b) Net formed strips (drainage nets) of different sizes c) Multilayer geotextile mats with humus, seeds or compost of different sizes (e.g. 10x30x200 mm) d) Multilayer geotextile net formed mats with humus, seeds or compost This paper describes the experimental results of the water absorption and water holding capacity of different forms of MINIDRAIN under different soil mixes. In this experiment, potting soil, coarse sand and LECA (Light weight clay aggregates) balls are mixed with different proportion of MINIDRAIN systems and

  15. Using Softer X-ray Absorption Spectroscopy to Probe Biological Systems

    SciTech Connect

    Akabayov,B.; Doonan, C.; Pickering, I.; George, G.; Sagi, I.

    2005-01-01

    Many inorganic species are now recognized as being essential for life, including many forms of sulfur, phosphate and numerous classes of metal ions. For example, recent progress in the fields of biochemistry and biology has pointed out the critical importance of sulfur in the biosynthesis of vital cofactors and active sites in proteins, and in the complex reaction mechanisms often involved. Special attention has also been drawn to the diverse roles of alkaline (Na{sup +}, K{sup +}) and alkaline earth (Mg{sup 2+}, Ca{sup 2+}) metal ions in mediating the activity of RNA, proteins and many processes in living cells. While the general effect of these ions in biology is mostly understood, information on their detailed role is deficient. Here the application of softer X-ray absorption spectroscopy (XAS) to probe the local structural and electronic environment of such ions within their biological complexes and during physiological reactions is discussed. In addition, the required experimental set-up and the difficulties associated with conducting softer XAS experiments on biological samples are presented.

  16. Absorption coefficients of the methane-nitrogen binary ice system: Implications for Pluto

    NASA Astrophysics Data System (ADS)

    Protopapa, S.; Grundy, W. M.; Tegler, S. C.; Bergonio, J. M.

    2015-06-01

    The methane-nitrogen phase diagram of Prokhvatilov and Yantsevich (1983. Sov. J. Low Temp. Phys. 9, 94-98) indicates that at temperatures relevant to the surfaces of icy dwarf planets like Pluto, two phases contribute to the methane absorptions: nitrogen saturated with methane N2 ‾ :CH4 and methane saturated with nitrogen CH4 ‾ :N2 . No optical constants are available so far for the latter component limiting construction of a proper model, in compliance with thermodynamic equilibrium considerations. New optical constants for solid solutions of methane diluted in nitrogen (N2 :CH4) and nitrogen diluted in methane (CH4 :N2) are presented at temperatures between 40 and 90 K, in the wavelength range 1.1-2.7 μm at different mixing ratios. These optical constants are derived from transmission measurements of crystals grown from the liquid phase in closed cells. A systematic study of the changes of methane and nitrogen solid mixtures spectral behavior with mixing ratio and temperature is presented.

  17. Mid-infrared carbon monoxide detection system using differential absorption spectroscopy technique

    NASA Astrophysics Data System (ADS)

    Dong, Ming; Sui, Yue; Li, Guo-lin; Zheng, Chuan-tao; Chen, Mei-mei; Wang, Yi-ding

    2015-11-01

    A differential carbon monoxide (CO) concentration sensing device using a self-fabricated spherical mirror (e.g. light-collector) and a multi-pass gas-chamber is presented in this paper. Single-source dual-channel detection method is adopted to suppress the interferences from light source, optical path and environmental changes. Detection principle of the device is described, and both the optical part and the electrical part are developed. Experiments are carried out to evaluate the sensing performance on CO concentration. The results indicate that at 1.013×105 Pa and 298 K, the limit of detection (LoD) is about 11.5 mg/m3 with an absorption length of 40 cm. As the gas concentration gets larger than 115 mg/m3 (1.013×105 Pa, 298 K), the relative detection error falls into the range of -1.7%—+1.9%. Based on 12 h long-term measurement on the 115 mg/m3 and 1 150 mg/m3 CO samples, the maximum detection errors are about 0.9% and 5.5%, respectively. Due to the low cost and competitive characteristics, the proposed device shows potential applications in CO detection in the circumstances of coal-mine production and environmental protection.

  18. Design of a simple cryogenic system for ultraviolet-visible absorption spectroscopy with a back-reflectance fiber optic probe.

    PubMed

    Vinyard, Andrew; Hansen, Kaj A; Byrd, Ross; Stuart, Douglas A; Hansen, John E

    2014-01-01

    We report a convenient and inexpensive technique for the rapid acquisition of absorption spectra from small samples at cryogenic temperatures using a home built cryostat with novel collection optics. A cylindrical copper block was constructed with a coaxial bore to hold a 4.00 mm diameter electron paramagnetic resonance (EPR) tube and mounted on a copper feed in thermal contact with liquid nitrogen. A 6.35 mm diameter hole was bored into the side of the cylinder so a fiber optic cable bundle could be positioned orthogonally to the EPR tube. The light passing through the sample is reflected off of the opposing surfaces of the EPR tube and surrounding copper, back through the sample. The emergent light is then collected using the fiber optic bundle and analyzed using a dispersive spectrometer. Absorption spectra for KMnO4 were measured between 400 and 700 nm. Absorption intensity at 506, 525, 545, and 567 nm was found to be proportional to concentration, displaying Beer's law-like behavior. The EPR tube had an internal diameter of 3.2 mm; the double pass of the probe beam through the sample affords a central path length of about 6.4 mm. Comparing these measurements with those recorded on a conventional tabletop spectrometer using a cuvette with a 10.00 mm path length, we consistently found a ratio between intensities of 0.58 rather than the anticipated 0.64. These 6% smaller values we attribute to the curvature of the EPR tube and transmission/reflection losses. This system is particularly well-suited to studying the kinetics and dynamics of chemical reactions at cryogenic temperatures. The rapid response (100 ms) and multiplex advantage provided the opportunity of recording simultaneous time courses at several wavelengths following initiation of a chemical reaction with a pulsed laser source. PMID:24405962

  19. Physiologically Based In vitro Models to Predict the Oral Dissolution and Absorption of a Solid Drug Delivery System.

    PubMed

    Li, Ziqiang; He, Xin

    2015-01-01

    To understand the sophisticated dynamic behaviors of drug elution and permeation in the gastrointestinal tract (GIT), researchers have tried to reemerge it by employing various in vitro experimental models. However, official in vitro apparatuses routinely used for quality control purposes, employ simple, non-physiologic buffers, and hydrodynamics conditions, and can not accurately perform continuous, dynamic in vivo pharmacokinetics (PK) behaviors. Therefore, different angles of GI physiology information are incorporate into novel models to forecast the dissolution and permeation of drug solid dosage forms. This review, in general, discusses some related studies of physiologically-based mechanical models to predict human absorption following oral administration in four sections. First the GIT, taken out of a complex physiological environment, where the drug is absorbed, distributed, metabolized and excreted (ADME) in the human body, is considered as the physiological basis for active pharmaceutics ingredients (API) dissolved and permeated through the epithelial cell. The second part embodies the theoretical foundation of in vitro models to predict human absorption and the corresponding in vitro.in vivo correlations (IVIVC). The third section summarizes physiologically based dissolution models developed recently, ranging from dynamic compartmental dissolution models, to biorelevant dissolution models based on certain physiological factors, to biphasic dissolution models. The last part is devoted to combined dissolution and absorption models that can be employed to simulate the continuous, dynamic behavior of oral drug delivery being dissolved and subsequently permeated across the GIT. Along with physiologically-based mechanically models spring up, pharmaceutical researchers will harvest better level A IVIVC for oral drug delivery systems, especially for sustained and controlled release preparations. On the other way hand, it will successively promote more effective

  20. Mechanism of enhanced oral absorption of morin by phospholipid complex based self-nanoemulsifying drug delivery system.

    PubMed

    Zhang, Jinjie; Li, Jianbo; Ju, Yuan; Fu, Yao; Gong, Tao; Zhang, Zhirong

    2015-02-01

    Phospholipid complex (PLC) based self-nanoemulsifying drug delivery system (PLC-SNEDDS) has been developed for efficient delivery of drugs with poor solubility and low permeability. In the present study, a BCS class IV drug and a P-glycoprotein (P-gp) substrate, morin, was selected as the model drug to elucidate the oral absorption mechanism of PLC-SNEDDS. PLC-SNEDDS was superior to PLC in protecting morin from degradation by intestinal enzymes in vitro. In situ perfusion study showed increased intestinal permeability by PLC was duodenum-specific. In contrast, PLC-SNEDDS increased morin permeability in all intestinal segments and induced a change in the main absorption site of morin from colon to ileum. Moreover, ileum conducted the lymphatic transport of PLC-SNEDDS, which was proven by microscopic intestinal visualization of Nile red labeled PLC-SNEDDS and lymph fluids in vivo. Low cytotoxicity and increased Caco-2 cell uptake suggested a safe and efficient delivery of PLC-SNEDDS. The increased membrane fluidity and disrupted actin filaments were closely associated with the increased cell uptake of PLC-SNEDDS. PLC-SNEDDS could be internalized into enterocytes as an intact form in a cholesterol-dependent manner via clathrin-mediated endocytosis and macropinocytosis. The enhanced oral absorption of morin was attributed to the P-gp inhibition by Cremophor RH and the intact internalization of M-PLC-SNEDDS into Caco-2 cells bypassing P-gp recognition. Our findings thus provide new insights into the development of novel nanoemulsions for poorly absorbed drugs.

  1. GcoGSA-BA: a global core genome SNP analysis for Bacillus anthracis.

    PubMed

    Yamashita, Akifmi; Sekizuka, Tsuyoshi; Kuroda, Makoto

    2015-01-01

    As an issue of biosecurity, it is important to identify the origin of a suspected sample to distinguish whether it originated from the release of a bioterrorism agent or from environmental contamination with a virulent agent. Here we have developed an analytical pipeline that can infer the phylogenetic position of Bacillus cereus group species, including B. anthracis, from next-generation sequencing reads without extensive genomics skills. GcoGSA-BA can also detect the existence of anthrax plasmid pXO1 carrying 3 anthrax toxins (lethal factor, edema factor, and protective antigen). This pipeline can also be used to correctly infer the phylogenetic position and to detect the suspected isolate carrying anthrax toxins among B. cereus group.

  2. Asymmetric absorption and emission of energy by a macroscopic mechanical oscillator in a microwave circuit optomechanical system

    NASA Astrophysics Data System (ADS)

    Harlow, Jennifer; Palomaki, Tauno; Kerckhoff, Joseph; Teufel, John; Simmonds, Raymond; Lehnert, Konrad

    2012-02-01

    We measure the asymmetry in rates for emission and absorption of mechanical energy in an electromechanical system composed of a macroscopic suspended membrane coupled to a high-Q, superconducting microwave resonant circuit. This asymmetry is inherently quantum mechanical because it arises from the inability to annihilate the mechanical ground state. As such, it is only appreciable when the average mechanical occupancy approaches one. This measurement is now possible due to the recent achievement of ground state cooling of macroscopic mechanical oscillators [1,2]. Crucially, we measure the thermal cavity photon occupancy and account for it in our analysis. Failure to correctly account for the interference of these thermal photons with the mechanical signal can lead to a misinterpretation of the data and an overestimate of the emission/absorption asymmetry. [4pt] [1] J. D. Teufel, T. Donner, Dale Li, J. W. Harlow, M. S. Allman, K. Cicak, A. J. Sirois, J. D. Whittaker, K. W. Lehnert, R. W. Simmonds, ``Sideband Cooling Micromechanical Motion to the Quantum Ground State,'' Nature, 475, 359-363 (2011).[0pt] [2] Jasper Chan, et al, ``Laser cooling of a nanomechanical oscillator into its quantum ground state,'' Nature, 478, 89-92 (2011).

  3. In operando observation system for electrochemical reaction by soft X-ray absorption spectroscopy with potential modulation method

    SciTech Connect

    Nagasaka, Masanari Kosugi, Nobuhiro; Yuzawa, Hayato; Horigome, Toshio

    2014-10-15

    In order to investigate local structures of electrolytes in electrochemical reactions under the same scan rate as a typical value 100 mV/s in cyclic voltammetry (CV), we have developed an in operando observation system for electrochemical reactions by soft X-ray absorption spectroscopy (XAS) with a potential modulation method. XAS spectra of electrolytes are measured by using a transmission-type liquid flow cell with built-in electrodes. The electrode potential is swept with a scan rate of 100 mV/s at a fixed photon energy, and soft X-ray absorption coefficients at different potentials are measured at the same time. By repeating the potential modulation at each fixed photon energy, it is possible to measure XAS of electrochemical reaction at the same scan rate as in CV. We have demonstrated successful measurement of the Fe L-edge XAS spectra of aqueous iron sulfate solutions and of the change in valence of Fe ions at different potentials in the Fe redox reaction. The mechanism of these Fe redox processes is discussed by correlating the XAS results with those at different scan rates.

  4. Demonstration of an on-site PAFC cogeneration system with waste heat utilization by a new gas absorption chiller

    SciTech Connect

    Urata, Tatsuo

    1996-12-31

    Analysis and cost reduction of fuel cells is being promoted to achieve commercial on-site phosphoric acid fuel cells (on-site FC). However, for such cells to be effectively utilized, a cogeneration system designed to use the heat generated must be developed at low cost. Room heating and hot-water supply are the most simple and efficient uses of the waste heat of fuel cells. However, due to the short room-heating period of about 4 months in most areas in Japan, the sites having demand for waste heat of fuel cells throughout the year will be limited to hotels and hospitals Tokyo Gas has therefore been developing an on-site FC and the technology to utilize tile waste heat of fuel cells for room cooling by means of an absorption refrigerator. The paper describes the results of fuel cell cogeneration tests conducted on a double effect gas absorption chiller heater with auxiliary waste heat recovery (WGAR) that Tokyo Gas developed in its Energy Technology Research Laboratory.

  5. Detection of gastrointestinal cancer by elastic scattering and absorption spectroscopies with the Los Alamos Optical Biopsy System

    SciTech Connect

    Mourant, J.R.; Boyer, J.; Johnson, T.M.; Lacey, J.; Bigio, I.J.; Bohorfoush, A.; Mellow, M.

    1995-03-01

    The Los Alamos National Laboratory has continued the development of the Optical Biopsy System (OBS) for noninvasive, real-time in situ diagnosis of tissue pathologies. In proceedings of earlier SPIE conferences we reported on clinical measurements in the bladder, and we report here on recent results of clinical tests in the gastrointestinal tract. With the OBS, tissue pathologies are detected/diagnosed using spectral measurements of the elastic optical transport properties (scattering and absorption) of the tissue over a wide range of wavelengths. The use of elastic scattering as the key to optical tissue diagnostics in the OBS is based on the fact that many tissue pathologies, including a majority of cancer forms, exhibit significant architectural changes at the cellular and sub-cellular level. Since the cellular components that cause elastic scattering have dimensions typically on the order of visible to near-IR wavelengths, the elastic (Mie) scattering properties will be wavelength dependent. Thus, morphology and size changes can be expected to cause significant changes m an optical signature that is derived from the wavelength-dependence of elastic scattering. Additionally, the optical geometry of the OBS beneficially enhances its sensitivity for measuring absorption bands. The OBS employs a small fiber-optic probe that is amenable to use with any endoscope or catheter, or to direct surface examination, as well as interstitial needle insertion. Data acquistion/display time is <1 second.

  6. Clean Coal Technology III (CCT III) 10 MW demonstration of gas suspension absorption. Fourth quarterly technical progress report, July 1, 1991--September 30, 1991

    SciTech Connect

    Not Available

    1992-02-07

    The Gas Suspension Absorber (GSA) system brings coal combustion gases into contact with a suspended mixture of solids, including sulfur-absorbing lime. After the lime absorbs the sulfur pollutants, the solids are separated from the gases in a cyclone device and recirculated back into the system where they capture additional sulfur pollutant. The cleaned flue gases are sent through a dust collector before being released into the atmosphere. The key to the system`s superior economic performance with high sulfur coals is the recirculation of solids. Typically, a solid particle will pass through the system about one hundred times before leaving the system. Another advantage of the GSA system is that a single spray nozzle is used to inject fresh lime slurry. The GSA system is expected to be the answer to the need of the US industry for an effective, economic and space efficient solution to the SO{sub 2} pollution problem.

  7. Study on erythrosine-phen-Cd(II) systems by resonance Rayleigh scattering, absorption spectra and their analytical applications

    NASA Astrophysics Data System (ADS)

    Tian, Jing; Zhang, Qiqi; Liu, Shaopu; Yang, Jidong; Teng, Ping; Zhu, Jinghui; Qiao, Man; Shi, Ying; Duan, Ruilin; Hu, Xiaoli

    2015-04-01

    In pH 7.0-8.0 KH2PO4-Na2HPO4 buffer solution, Cd(II) reacted with 1,10-phenanthroline to form chelate cation [Cd(phen)3]2+, which further reacted with anion of erythrosine to form ternary ion-association complex through electrostatic attraction and hydrophobic effect. This process could result in remarkable absorption spectra change and produce obvious fading reaction at 528 nm. Absorbance change (ΔA) of system was directly proportional to the concentration of Cd(II). Hereby, a highly sensitive spectrophotometric method for the determination of Cd(II) was established. The molar absorption coefficient was 2.29 × 105 L mol-1 cm-1 and the detection limit of Cd(II) was 26.5 ng mL-1. Furthermore, the resonance Rayleigh scattering (RRS) of this system with two peaks located at 371 and 590 nm enhanced significantly, and second-order scattering (SOS) and frequence doubling scattering (FDS) of this system changed notably at 640 and 350 nm, respectively. Under the optimum conditions, the scattering intensities (ΔIRRS, ΔIDWO-RRS, ΔISOS and ΔIFDS) had good linear relationship with the concentration of Cd(II) in certain ranges. The detection limits of Cd(II) were 1.27 ng mL-1, 1.39 ng mL-1, 4.03 ng mL-1, 5.92 ng mL-1 and 14.7 ng mL-1 for dual-wavelength overlapping resonance Rayleigh scattering (DWO-RRS), RRS (371 nm), RRS (590 nm), SOS and FDS, respectively. In addition, the suitable reaction conditions and effects of coexisting substances were investigated. The methods had been successfully applied to the determination of Cd(II) in environmental water samples. The recovery range was between 93.0% and 103.0% and the relative standard deviation (RSD) was between 2.5% and 4.3%. The results were in agreement with those obtained from atomic absorption spectroscopy.

  8. Improved oral absorption of dutasteride via Soluplus®-based supersaturable self-emulsifying drug delivery system (S-SEDDS).

    PubMed

    Lee, Dong Hoon; Yeom, Dong Woo; Song, Ye Seul; Cho, Ha Ra; Choi, Yong Seok; Kang, Myung Joo; Choi, Young Wook

    2015-01-15

    A novel supersaturable self-emulsifying drug delivery system (S-SEDDS) was formulated to improve the oral absorption of dutasteride (DTS), a 5α-reductase inhibitor that is poorly water-soluble. A supersaturable system was prepared by employing Soluplus(®) (polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer) as a precipitation inhibitor with a conventional SEDDS vehicle consisted of Capryol™ 90, Cremophor(®) EL and Transcutol(®) HP (DTS:SEDDS vehicle:Soluplus(®)=1.0:67.6:10.0 w/v/w). In an in vitro dissolution test in a non-sink condition, the drug dissolution rate from SEDDS was rapidly increased to 72% for an initial period of 5min, but underwent rapid drug precipitation within 2h, decreasing the amount of drug dissolved to one-seventh of its original amount. On the other hand, S-SEDDS resulted in a slower crystallization of DTS by virtue of a precipitation inhibitor, maintaining a 3 times greater dissolution rate after 2h compared to SEDDS. In an in vivo pharmacokinetic study in rats, the S-SEDDS formulation exhibited 3.9-fold greater area-under-curve value than that of the drug suspension and 1.3-fold greater than that of SEDDS. The maximum plasma concentration of S-SEDDS was 5.6- and 2.0-fold higher compared to drug suspension and SEDDS, respectively. The results of this study suggest that the novel supersaturable system may be a promising tool for improving the physicochemical property and oral absorption of the 5α-reductase inhibitor. PMID:25437113

  9. Design of Advanced Atmospheric Water Vapor Differential Absorption Lidar (DIAL) Detection System

    NASA Technical Reports Server (NTRS)

    Refaat, Tamer F.; Luck, William S., Jr.; DeYoung, Russell J.

    1999-01-01

    The measurement of atmospheric water vapor is very important for understanding the Earth's climate and water cycle. The lidar atmospheric sensing experiment (LASE) is an instrument designed and operated by the Langley Research Center for high precision water vapor measurements. The design details of a new water vapor lidar detection system that improves the measurement sensitivity of the LASE instrument by a factor of 10 are discussed. The new system consists of an advanced, very low noise, avalanche photodiode (APD) and a state-of-the-art signal processing circuit. The new low-power system is also compact and lightweight so that it would be suitable for space flight and unpiloted atmospheric vehicles (UAV) applications. The whole system is contained on one small printed circuit board (9 x 15 sq cm). The detection system is mounted at the focal plane of a lidar receiver telescope, and the digital output is read by a personal computer with a digital data acquisition card.

  10. Thermal design of lithium bromide-water solution vapor absorption cooling system for indirect evaporative cooling for IT pod

    NASA Astrophysics Data System (ADS)

    Sawant, Digvijay Ramkrishna

    Nowadays with increase use of internet, mobile there is increase in heat which ultimately increases the efficient cooling system of server room or IT POD. Use of traditional ways of cooling system has ultimately increased CO2 emission and depletion of CFC's are serious environmental issues which led scientific people to improve cooling techniques and eliminate use of CFC's. To reduce dependency on fossil fuels and 4environmental friendly system needed to be design. For being utilizing low grade energy source such as solar collector and reducing dependency on fossil fuel vapour absorption cooling system has shown a great driving force in today's refrigeration systems. This LiBr-water aabsorption cooling consists of five heat exchanger namely: Evaporator, Absorber, Solution Heat Exchanger, Generator, Condenser. The thermal design was done for a load of 23 kW and the procedure was described in the thesis. There are 120 servers in the IT POD emitting 196 W of heat each on full load and some of the heat was generated by the computer placed inside the IT POD. A detailed procedure has been discussed. A excel spreadsheet was to prepared with varying tube sizes to see the effect on flows and ultimately overall heat transfer coefficient.

  11. An Ozone Differential Absorption Lidar (DIAL) Receiver System for Use on Unpiloted Atmospheric Vehicles

    NASA Technical Reports Server (NTRS)

    DeYoung, Russell J.; Goldschmidt, Soenke

    1999-01-01

    Measurements of global atmosphere ozone concentrations call for flexible lidar systems that can be operated from an unpiloted atmospheric vehicle (UAV) to reduce the cost of measurement missions. A lidar receiver system consisting of a fiber-optic-coupled telescope has been designed and tested for this purpose. The system weight is 13 kg and its volume of 0.06 m 3 would fit into the payload compartment of a Perseus B UAV. The optical efficiency of the telescope is 37 percent at 288 nm and 64 percent at 300 nm. Atmospheric measurements with a DIAL laser system have been performed, and the measured ozone density has matched the data from ozonesondes to an altitude of 7 km.

  12. Real-time intraoperative fluorescence imaging system using light-absorption correction

    NASA Astrophysics Data System (ADS)

    Themelis, George; Yoo, Jung Sun; Soh, Kwang-Sup; Schulz, Ralf; Ntziachristos, Vasilis

    2009-11-01

    We present a novel fluorescence imaging system developed for real-time interventional imaging applications. The system implements a correction scheme that improves the accuracy of epi-illumination fluorescence images for light intensity variation in tissues. The implementation is based on the use of three cameras operating in parallel, utilizing a common lens, which allows for the concurrent collection of color, fluorescence, and light attenuation images at the excitation wavelength from the same field of view. The correction is based on a ratio approach of fluorescence over light attenuation images. Color images and video is used for surgical guidance and for registration with the corrected fluorescence images. We showcase the performance metrics of this system on phantoms and animals, and discuss the advantages over conventional epi-illumination systems developed for real-time applications and the limits of validity of corrected epi-illumination fluorescence imaging.

  13. Emittance and absorptance of NASA ceramic thermal barrier coating system. [for turbine cooling

    NASA Technical Reports Server (NTRS)

    Liebert, C. H.

    1978-01-01

    Spectral emittance measurements were made on a two-layer ceramic thermal barrier coating system consisting of a metal substrate, a NiCrAly bond coating and a yttria-stabilized zirconia ceramic coating. Spectral emittance data were obtained for the coating system at temperatures of 300 to 1590 K, ceramic thickness of zero to 0.076 centimeter, and wavelengths of 0.4 to 14.6 micrometers. The data were transformed into total hemispherical emittance values and correlated with respect to ceramic coating thickness and temperature using multiple regression curve fitting techniques. The results show that the ceramic thermal barrier coating system is highly reflective and significantly reduces radiation heat loads on cooled gas turbine engine components. Calculation of the radiant heat transfer within the nonisothermal, translucent ceramic coating material shows that the gas-side ceramic coating surface temperature can be used in heat transfer analysis of radiation heat loads on the coating system.

  14. Design of mini-multi-gas monitoring system based on IR absorption

    NASA Astrophysics Data System (ADS)

    Tan, Qiu-lin; Zhang, Wen-dong; Xue, Chen-yang; Xiong, Ji-jun; Ma, You-chun; Wen, Fen

    2008-07-01

    In this paper, a novel non-dispersive infrared ray (IR) gas detection system is described. Conventional devices typically include several primary components: a broadband source (usually an incandescent filament), a rotating chopper shutter, a narrow-band filter, a sample tube and a detector. But we mainly use the mini-multi-channel detector, electrical modulation means and mini-gas-cell structure. To solve the problems of gas accidents in coal mines, and for family safety that results from using gas, this new IR detection system with integration, miniaturization and non-moving parts has been developed. It is based on the principle that certain gases absorb infrared radiation at specific (and often unique) wavelengths. The infrared detection optics principle used in developing this system is mainly analyzed. The idea of multi-gas detection is introduced and guided through the analysis of the single-gas detection. Through researching the design of cell structure, a cell with integration and miniaturization has been devised. By taking a single-chip microcomputer (SCM) as intelligence handling, the functional block diagram of a gas detection system is designed with the analyzing and devising of its hardware and software system. The way of data transmission on a controller area network (CAN) bus and wireless data transmission mode is explained. This system has reached the technology requirement of lower power consumption, mini-volume, wide measure range, and is able to realize multi-gas detection.

  15. Depolarisation of light scattered by disperse systems of low-dimensional potassium polytitanate nanoparticles in the fundamental absorption band

    SciTech Connect

    Zimnyakov, D A; Yuvchenko, S A; Pravdin, A B; Kochubey, V I; Gorokhovsky, A V; Tretyachenko, E V; Kunitsky, A I

    2014-07-31

    The results of experimental studies of depolarising properties of disperse systems on the basis of potassium polytitanate nanoplatelets and nanoribbons in the visible and near-UV spectral regions are presented. It is shown that in the fundamental absorption band of the nanoparticle material the increase in the depolarisation factor takes place for the radiation scattered perpendicularly to the direction of the probing beam. For nanoribbons a pronounced peak of depolarisation is observed, which is caused by the essential anisotropy of the particles shape and the peculiarities of the behaviour of the material dielectric function. The empirical data are compared with the theoretical results for 'nanodiscs' and 'nanoneedles' with the model dielectric function, corresponding to that obtained from optical constants of the titanium dioxide dielectric function. (laser biophotonics)

  16. Clues to the nature of high-redshift O vi absorption systems from their lack of small-scale structure

    NASA Astrophysics Data System (ADS)

    Lopez, S.; Ellison, S.; D'Odorico, S.; Kim, T.-S.

    2007-07-01

    We present results of the first survey of high-redshift (< z>˜ 2.3) O VI absorption systems along parallel lines of sight toward two lensed QSOs. After a careful and well-defined search, we find ten intervening O VI systems - identified by the presence of the λλ1031, 1037 doublet lines, H I, and in most cases C IV, Si IV, and C III - and eight candidate systems for which we do not detect H I nor other metals. We assess the veracity of these systems by applying a classification scheme. Within the errors, all O VI systems appear at the same redshift and have similar line strengths in front of both QSO images, whereas in most cases C IV or Si IV show more differences across the lines of sight, either in radial velocity or line strength. We conclude that (1) the coherence length of O VI must be much larger than ≈ 1 h70-1 kpc, and (2) an important fraction of the C IV absorbers may not reside in the same volume as O VI. Given the inhomogeneous character of the data - different S/N ratios and degrees of blending - we pay special attention to the observational errors and their impact on the above conclusions. Since Doppler parameters are consistent with photoionization, we propose a model in which V IV occurs in two different photoionized phases, one large, with characteristic sizes of a few hundred kpc and bearing O VI, and another one a factor of ten smaller and containing C III. This model is able to explain the various transverse differences observed in column density and kinematics. We apply the model successfully to 2 kinds of absorbers, with low and high metallicity. In the low-metallicity regime, [C/H]~ -2, we find that [C/O] ≈ -0.7 is required to explain the observations, which hints at late (z⪉ 6) rather than early metal enrichment. In the high-metallicity regime, the observed dissociation between O VI and C IV gas might be produced by galactic outflows. Altogether, the relative abundances, inhomogeneous C IV and featureless O VI are consistent with gas

  17. Modulated Sine Waves for Differential Absorption Measurements Using a CW Laser System

    NASA Technical Reports Server (NTRS)

    Campbell, Joel F. (Inventor); Lin, Bing (Inventor); Nehrir, Amin R. (Inventor)

    2015-01-01

    A continuous wave Light Detection and Ranging (CW LiDAR) system utilizes two or more laser frequencies and time or range shifted pseudorandom noise (PN) codes to discriminate between the laser frequencies. The performance of these codes can be improved by subtracting out the bias before processing. The CW LiDAR system may be mounted to an artificial satellite orbiting the earth, and the relative strength of the return signal for each frequency can be utilized to determine the concentration of selected gases or other substances in the atmosphere.

  18. In-situ liquid storage capacity measurement of subsurface wastewater absorption system products.

    PubMed

    Quisenberry, Virgil; Brown, Philip; Smith, Bill; Hallahan, Dennis F

    2006-11-01

    A method is presented for measuring the in-situ liquid storage capacity of subsurface wastewater infiltration system (SWIS) products. While these products vary in composition, geometry, and porosity, they all have the same function: to provide a conduit for the flow of effluent from a septic tank to and through a trench so that infiltration into the soil can occur. A functional SWIS must also provide temporary liquid storage. Storage is necessary for periods when discharge from the septic tank exceeds the infiltration rate of the soil. Storage is also important during times when the soil in and around the trench is saturated. Many states now have regulatory requirements pertaining to storage volume, and these requirements commonly establish the traditional gravel-pipe system as the standard for minimally acceptable volume. Raliable comparisons between various alternative products and gravel have been difficult or impossible, because there has been no standard method for measuring storage volume. Some products have been evaluated under realistic field conditions; others have been evaluated under theoretical or ideal conditions. The protocol developed by the study reported here can serve as a common, accurate basis for comparisons. A 3-foot-deep trench was excavated, and the bottom was leveled. Markers (nails or rods) were attached to the products to indicate the invert and full-volume heights. The products were then enclosed in plastic, placed in a trench, and covered with soil. A 4-inch-diameter pipe extended from the product to the surface to allow metered additions of water into the products and precise determinations when the systems had been filled to capacity. Four plastic chambers, three expanded polystyrene (ESP) products, two multipipe arrangements, and a standard gravel-pipe system were evaluated. The standard gravel-pipe system held 10.2 gal/ft Three of the four plastic chambers stored from 100 to 130 percent of what the standard system held. The

  19. Development of a single-family absorption chiller for use in a solar heating and cooling system, phase 3, volume 2

    NASA Astrophysics Data System (ADS)

    Reimann, R. C.; Biermann, W. J.

    1984-10-01

    Supporting information is presented on: properties of a chemical system for solar fired, air-cooled absorption equipment, air-side performance of a one-inch tube, absorber plate-fin coil, listings of the programs used for simulation and data reduction, and evaluation of the Carrier three-tone chiller in an integrated heating and cooling system.

  20. Ab-initio calculations of the hydrogen-uranium system. Part I: Surface phenomena, absorption, transport and trapping

    SciTech Connect

    Taylor, Christopher D; Lillard, R Scott

    2009-01-01

    Density functional theory was applied to the initial steps of uranium hydriding: surface phenomena, absorption, bulk transport and trapping. H adsorbs exothermically to the (0 0 1) surface, yet H absorption into the bulk is endothermic, with off-center octahedral absorption having the lowest absorption energy of 0.39 eV, relative to molecular H{sub 2}. H absorption in interstitial sites causes a local softening of the bulk modulus. Diffusion of H in unstrained {alpha}-U has a barrier of 0.6 eV. The energy of H absorption adjacent to the chemical impurities C, S, Si was lowered by an amount proportional to the size of the impurity atom, and the resulting lattice strain Si > S > C. Thus, impurities may promote hydriding by providing surfaces or prestrained zones for H uptake.