Design and Development of a SNAP-8 Mercury Pump Motor Assembly

Design and performance of mercury pump motor for SNAP 8 electrical generato

Aircraft scanner data availability via the version 0 Information Management System

As part of the Earth Observing System Data and Information System (EOSDIS) development, NASA and other government agencies have developed an operational prototype of the Information Management System (IMS). The IMS provides access to the data archived at the Distributed Active Archive Centers (DAAC's) that allows users to search through metadata describing the (image) data. Criteria based on sensor name or type, date and time, and geographic location are used to search the archive. Graphical representations of coverage and browse images are available to further refine a user's selection. previously, the EROS Data Center (EDC) DAAC had identified the Advanced SOlid-state Array Spectrometer (ASAS), Airborne Visible and infrared Imaging Spectrometer (AVIRIS), NS-001, and Thermal Infrared Multispectral Scanner (TIMS) as precursor data sets similar to those the DAAC will handle in the Earth Observing System era. Currently, the EDC DAAC staff, in cooperation with NASA, has transcribed TIMS, NS-001, and Thematic Mapper Simulation (TMS) data from Ames Research Center and also TIMS data from Stennis Space Center. During the transcription process, the IMS metadata and browse images were created to populate the inventory at the EDC DAAC. These data sets are now available in the IMS and may be requested from the any of the DAAC's via the IMS

AVIRIS and TIMS data processing and distribution at the land processes distributed active archive center

The U.S. Government has initiated the Global Change Research program, a systematic study of the Earth as a complete system. NASA's contribution of the Global Change Research Program is the Earth Observing System (EOS), a series of orbital sensor platforms and an associated data processing and distribution system. The EOS Data and Information System (EOSDIS) is the archiving, production, and distribution system for data collected by the EOS space segment and uses a multilayer architecture for processing, archiving, and distributing EOS data. The first layer consists of the spacecraft ground stations and processing facilities that receive the raw data from the orbiting platforms and then separate the data by individual sensors. The second layer consists of Distributed Active Archive Centers (DAAC) that process, distribute, and archive the sensor data. The third layer consists of a user science processing network. The EOSDIS is being developed in a phased implementation. The initial phase, Version 0, is a prototype of the operational system. Version 0 activities are based upon existing systems and are designed to provide an EOSDIS-like capability for information management and distribution. An important science support task is the creation of simulated data sets for EOS instruments from precursor aircraft or satellite data. The Land Processes DAAC, at the EROS Data Center (EDC), is responsible for archiving and processing EOS precursor data from airborne instruments such as the Thermal Infrared Multispectral Scanner (TIMS), the Thematic Mapper Simulator (TMS), and Airborne Visible and Infrared Imaging Spectrometer (AVIRIS). AVIRIS, TIMS, and TMS are flown by the NASA-Ames Research Center ARC) on an ER-2. The ER-2 flies at 65000 feet and can carry up to three sensors simultaneously. Most jointly collected data sets are somewhat boresighted and roughly registered. The instrument data are being used to construct data sets that simulate the spectral and spatial characteristics of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument scheduled to be flown on the first EOS-AM spacecraft. The ASTER is designed to acquire 14 channels of land science data in the visible and near-IR (VNIR), shortwave-IR (SWIR), and thermal-IR (TIR) regions from 0.52 micron to 11.65 micron at high spatial resolutions of 15 m to 90 m. Stereo data will also be acquired in the VNIR region in a single band. The AVIRIS and TMS cover the ASTER VNIR and SWIR bands, and the TIMS covers the TIR bands. Simulated ASTER data sets have been generated over Death Valley, California, Cuprite, Nevada, and the Drum Mountains, Utah using a combination of AVIRIS, TIMS, amd TMS data, and existing digital elevation models (DEM) for the topographic information

The AGRHYMET data communications project

The U.S. Geological Survey (USGS) and the U.S. Agency for International Development (USAID) are providing technical assistance to the AGRHYMET program in West Africa. AGRHYMET staff use remote sensing technology to produce satellite image maps of the Sahel region of West Africa. These image maps may show vegetation greenness, sea surface temperatures, or processed weather satellite imagery. The image maps must be distributed from the AGRHYMET Regional Center in Niger to national AGRHYMET centers in the member countries of Burkina Faso, Cape Verde, Chad, Gambia, Guinea-Bissau, Mali, Mauritania, Niger, and Senegal. After consideration of a number of land- and space-based solutions for image map distribution, the best solution was determined to be use of International Maritime Satellite Organization (INMARSAT) land-based terminals. In April 1992, a field test and proof-of-concept demonstration using land-mobile terminals produced favorable results. The USGS and USAID are setting up a wide area network using INMARSAT terminals to link the AGRHYMET sites for image data transfer. The system is in the procurement and installation phase and initial opening capability may be operational for the 1993 growing season, starting in May 1993

Separation of microplastics from water using superhydrophobic silane-coupling-agent-modified geopolymer foam

Microplastics are a topical environmental problem that requires urgent solutions. They are ubiquitously present in various wastewaters and are discharged into aquatic environments because of difficulties in their removal. In this study, a novel filtration medium, superhydrophobic geopolymer foam, was prepared and investigated for the separation of microplastics from water. The foam was prepared using metakaolin, sodium silicate, sodium hydroxide, hydrogen peroxide, and Triton X-100 surfactant as raw materials and superhydrophobized with a silane coupling agent, triethoxy(octyl)silane. The purpose of the superhydrophobization was to improve the attachment of hydrophobic microplastic particles to the foam surface via chemical interactions. The modified geopolymer foam exhibited a water contact angle of 152°, and the presence of octyl chains on its surface was confirmed using Fourier transform infrared and X-ray photoelectron spectroscopies. When applied as a filter, the modified foam separated 53-63-µm sized polyethylene microspheres with ∼99 % removal efficiency, and no change in its separation efficiency was observed for ∼200 bed volumes of treated water. A comparison with an unmodified foam filter confirmed that the removal mechanism was not based on physical separation at higher flow rates, because the performance of the unmodified foam began to degrade after treating ∼5 bed volumes of wastewater. The performance of the modified foam was also validated with laundry washing effluents (particle size of microplastics varied roughly within 2–2000 μm), achieving ∼84 % separation efficiency for ∼50 bed volumes of wastewater. This study provides proof of concept of using superhydrophobic geopolymers as efficient, easy-to-prepare, and potentially low-cost separation media for microplastics from water effluents

Water Oxidation by a Cytochrome P450: Mechanism and Function of the Reaction

P450cam (CYP101A1) is a bacterial monooxygenase that is known to catalyze the oxidation of camphor, the first committed step in camphor degradation, with simultaneous reduction of oxygen (O2). We report that P450cam catalysis is controlled by oxygen levels: at high O2 concentration, P450cam catalyzes the known oxidation reaction, whereas at low O2 concentration the enzyme catalyzes the reduction of camphor to borneol. We confirmed, using 17O and 2H NMR, that the hydrogen atom added to camphor comes from water, which is oxidized to hydrogen peroxide (H2O2). This is the first time a cytochrome P450 has been observed to catalyze oxidation of water to H2O2, a difficult reaction to catalyze due to its high barrier. The reduction of camphor and simultaneous oxidation of water are likely catalyzed by the iron-oxo intermediate of P450cam, and we present a plausible mechanism that accounts for the 1:1 borneol:H2O2 stoichiometry we observed. This reaction has an adaptive value to bacteria that express this camphor catabolism pathway, which requires O2, for two reasons: 1) the borneol and H2O2 mixture generated is toxic to other bacteria and 2) borneol down-regulates the expression of P450cam and its electron transfer partners. Since the reaction described here only occurs under low O2 conditions, the down-regulation only occurs when O2 is scarce

Design of a pulse power supply unit for micro-ECM

Electrochemical micro-machining (μECM) requires a particular pulse power supply unit (PSU) to be developed in order to achieve desired machining performance. This paper summarises the development of a pulse PSU meeting the requirements of μECM. The pulse power supply provides tens of nanosecond pulse duration, positive and negative bias voltages and a polarity switching functionality. It fulfils the needs for tool preparation with reversed pulsed ECM on the machine. Moreover, the PSU is equipped with an ultrafast overcurrent protection which prevents the tool electrode from being damaged in case of short circuits. The developed pulse PSU was used to fabricate micro-tools out of 170 μm WC-Co alloy shafts via micro-electrochemical turning and drill deep holes via μECM in a disk made of 18NiCr6. The electrolyte used for both processes was a mixture of sulphuric acid and NaNO3 aqueous solutions.The research reported in this paper is supported by the European Commission within the project “Minimizing Defects in Micro-Manufacturing Applications (MIDEMMA)” (FP7-2011-NMP-ICT-FoF-285614

Living Walls in The City: Community Values and Expectations

There is an increasing interest in living walls in the urban environment, particularly when linked into green infrastructure for urban heat island mitigation. However, the social acceptance of such systems in Australia is largely untested. To address this knowledge gap, a survey of nineteen local government authorities and twenty living wall owners and managers was conducted. The survey participants included commercial and residential buildings. The survey was used to study living wall owners’ motivations and expectations of living walls as well as the social values attached to the installed infrastructure. This study related the experiences of living wall owners to the current technical knowledge of living walls and contextualised the benefits and costs of living walls for Australian homes and buildings within the public attitudes and motivations for installing such infrastructure. The survey found that social acceptance and the aesthetic values placed on living walls and greenery more broadly represented a substantial advantage for living walls

Living Walls in The City: Community Values and Expectations

There is an increasing interest in living walls in the urban environment, particularly when linked into green infrastructure for urban heat island mitigation. However, the social acceptance of such systems in Australia is largely untested. To address this knowledge gap, a survey of nineteen local government authorities and twenty living wall owners and managers was conducted. The survey participants included commercial and residential buildings. The survey was used to study living wall owners’ motivations and expectations of living walls as well as the social values attached to the installed infrastructure. This study related the experiences of living wall owners to the current technical knowledge of living walls and contextualised the benefits and costs of living walls for Australian homes and buildings within the public attitudes and motivations for installing such infrastructure. The survey found that social acceptance and the aesthetic values placed on living walls and greenery more broadly represented a substantial advantage for living walls

The Effects of Cognitive Stress on Asthma Exacerbations among University Students

Introduction: Many asthmatics complain of worsening respiratory symptoms during periods of stress.This study evaluated the relationship among asthma symptoms, lung physiology, inflammatory parametersand perceived cognitive stress and quality of life in healthy adult students. This relationship was assessedat two time points: a time of normal activity and at a time of cognitive stress during academic examinations. Methods: Subjects attended the University of Alberta Hospital for a screening visit, which included aclinical exam, spirometry, methacholine challenge, allergen skin tests to assess atopy status and MiniInternational Neuropsychiatric Interview (MINI). Eligible subjects returned for a low stress visit (LSV) atleast 14 days prior to an exam and a high stress visit (HSV) within 24 hours of an exam. Spirometry, andmethacholine challenge were performed during both LSV and HSV along with the collection of urine (testedfor cortisol), and the administration of 4 questionnaires to assess perceived stress and quality of life. Results: Subjects showed no significant change in psychosocial or quality of life questionnaires betweenLSV and HSV. No significant change was noted in lung function or urine cortisol. There was an unexpectedhigh rate of pre-existing psychiatric comorbidities in this population (based on the MINI screen failure rate).Conclusion: We did not find a significant change in quality of life, psychosocial wellbeing or pulmonaryfunction or inflammation, measured by urine cortisol, during a high stress period. The high rate ofcomorbidities would be important to consider as part of evaluation used in clinical asthma studies in the future