615 research outputs found
Development of sensors for ceramic components in advanced propulsion systems
The 'Development of Sensors for Ceramics Components in Advanced Propulsion Systems' program was divided into two phases. The objectives of Phase 1 were to analyze, evaluate and recommend sensor concepts for the measurement of surface temperature, strain and heat flux on ceramic components for advanced propulsion systems. The results of this effort were previously published in NASA CR-182111. As a result of Phase 1, three approaches were recommended for further development: pyrometry, thin-film sensors, and thermographic phosphors. The objectives of Phase 2 were to fabricate and conduct laboratory demonstration tests of these systems. A summary report of the Phase 2 effort, together with conclusions and recommendations for each of the categories evaluated, has been submitted to NASA. Emittance tests were performed on six materials furnished by NASA Lewis Research Center. Measurements were made of various surfaces at high temperature using a Thermogage emissometer. This report describes the emittance test program and presents a summary of the results
NASA NDE Applications for Mobile MEMS Devices and Sensors
NASA would like new devices and sensors for performing nondestructive evaluation (NDE) of aerospace vehicles. These devices must be small in size/volume, mass, and power consumption. The devices must be autonomous and mobile so they can access the internal structures of aircraft and spacecraft and adequately monitor the structural health of these craft. The platforms must be mobile in order to transport NDE sensors for evaluating structural integrity and determining whether further investigations will be required. Microelectromechanical systems (MEMS) technology is crucial to the development of the mobile platforms and sensor systems. This paper presents NASA s needs for micro mobile platforms and MEMS sensors that will enable NDE to be performed on aerospace vehicles
Advanced organic chemistry laboratory curricula in Australian universities: Investigating the major topics and approaches to learning
A key goal of tertiary education is to prepare graduates with the training, skills, and knowledge necessary to thrive in the workforce. In chemistry, 50% of undergraduate students from Australia, New Zealand and the UK plan to pursue a career that uses chemistry (Ogunde et al., 2017). However, it has also been noted that there is a mismatch in the skills desired by industry when compared with what is taught to undergraduates (Martin et al., 2011; Yasin & Yueying, 2017). Laboratory work is an essential part of undergraduate programs with the objective of developing practical and interpersonal skills with âreal worldâ engagement in chemistry. It is therefore concerning to note the perception among industry stakeholders that the laboratory skills of high-achieving chemistry graduates do not meet the desired standard (Kirton et al., 2014).
To extend our understanding regarding the importance and value of undergraduate laboratory skills, techniques, and equipment usage; semi-structured interviews were conducted with key external stakeholders, academics, and post-graduate teaching staff. This presentation will discuss the key findings from our perspectives analysis interviews with various organic chemistry experts across the country from both industry and academia. Key findings include the belief: the purpose of second-year laboratory courses is to teach and developing competency with laboratory skills, whilst third-year laboratory courses should build on this with student application of learned skills whether through lab project design or problem-solving tasks/challenges.
REFERENCES
Kirton, S. B., Al-Ahmad, A., & Fergus, S. (2014). Using Structured Chemistry Examinations (SChemEs) As an Assessment Method To Improve Undergraduate Studentsâ Generic, Practical, and Laboratory-Based Skills. Journal of Chemical Education, 91(5), 648-654.
Martin, C. B., Schmidt, M., & Soniat, M. (2011). A Survey of the Practices, Procedures, and Techniques in Undergraduate Organic Chemistry Teaching Laboratories. Journal of Chemical Education, 88(12), 1630-1638.
Ogunde, J. C., Overton, T. L., Thompson, C. D., Mewis, R., & Boniface, S. (2017). Beyond graduation: motivations and career aspirations of undergraduate chemistry students [10.1039/C6RP00248J]. Chemistry Education Research and Practice, 18(3), 457-471.
Yasin, N. Y. B. M., & Yueying, O. (2017). Evaluating the Relevance of the Chemistry Curriculum to the Workplace: Keeping Tertiary Education Relevant. Journal of Chemical Education, 94(10), 1443-1449
Advanced Organic Chemistry laboratory curricula in Australian universities: Investigating the major topics and approaches to learning
A key goal of tertiary education is to prepare graduates with the training, skills, and knowledge necessary to thrive in the workforce. In chemistry, 50% of undergraduate students from Australia, New Zealand and the UK plan to pursue a career that uses chemistry (Ogunde et al., 2017). However, it has also been noted that there is a mismatch in the skills desired by industry when compared with what is taught to undergraduates (Martin et al., 2011; Yasin & Yueying, 2017). Laboratory work is an essential part of undergraduate programs with the objective of developing practical and interpersonal skills with âreal worldâ engagement in chemistry. It is therefore concerning to note the perception among industry stakeholders that the laboratory skills of high-achieving chemistry graduates do not meet the desired standard (Kirton et al., 2014).
This project aims to investigate how we can better develop higher level undergraduate chemistry laboratory programs to improve training and competency with industrially relevant skills. This research will undertake an initial investigation into the current organic chemistry laboratory curricula of second- and third-year courses in Australian universities through content analysis of laboratory manuals and unit outlines. To extend our understanding, semi-structured interviews will be conducted with key external stakeholders, academics, and post-graduate teaching staff. This presentation will introduce the initial stages of this project and expand on our intentions to utilise these data to develop an intervention and set of recommendations for undergraduate laboratories.
REFERENCES
Kirton, S. B., Al-Ahmad, A., & Fergus, S. (2014). Using Structured Chemistry Examinations (SChemEs) as an assessment method to improve undergraduate studentsâ generic, practical, and laboratory-based skills. Journal of Chemical Education, 91(5), 648-654.
Martin, C. B., Schmidt, M., & Soniat, M. (2011). A survey of the practices, procedures, and techniques in undergraduate organic chemistry teaching laboratories. Journal of Chemical Education, 88(12), 1630-1638.
Ogunde, J. C., Overton, T. L., Thompson, C. D., Mewis, R., & Boniface, S. (2017). Beyond graduation: Motivations and career aspirations of undergraduate chemistry students. Chemistry Education Research and Practice, 18(3), 457-471.
Yasin, N. Y. B. M., & Yueying, O. (2017). Evaluating the relevance of the chemistry curriculum to the workplace: Keeping tertiary education relevant. Journal of Chemical Education, 94(10), 1443-1449
Evaluating the GeoSnap 13-m Cut-Off HgCdTe Detector for mid-IR ground-based astronomy
New mid-infrared HgCdTe (MCT) detector arrays developed in collaboration with
Teledyne Imaging Sensors (TIS) have paved the way for improved 10-m
sensors for space- and ground-based observatories. Building on the successful
development of longwave HAWAII-2RGs for space missions such as NEO Surveyor, we
characterize the first 13-m GeoSnap detector manufactured to overcome the
challenges of high background rates inherent in ground-based mid-IR astronomy.
This test device merges the longwave HgCdTe photosensitive material with
Teledyne's 2048x2048 GeoSnap-18 (18-m pixel) focal plane module, which is
equipped with a capacitive transimpedance amplifier (CTIA) readout circuit
paired with an onboard 14-bit analog-to-digital converter (ADC). The final
assembly yields a mid-IR detector with high QE, fast readout (>85 Hz), large
well depth (>1.2 million electrons), and linear readout.
Longwave GeoSnap arrays would ideally be deployed on existing ground-based
telescopes as well as the next generation of extremely large telescopes. While
employing advanced adaptive optics (AO) along with state-of-the-art diffraction
suppression techniques, instruments utilizing these detectors could attain
background- and diffraction-limited imaging at inner working angles <10
, providing improved contrast-limited performance compared to JWST
MIRI while operating at comparable wavelengths. We describe the performance
characteristics of the 13-m GeoSnap array operating between 38-45K,
including quantum efficiency, well depth, linearity, gain, dark current, and
frequency-dependent (1/f) noise profile.Comment: 17 pages, 17 figures. Accepted for publication in special addition of
Astronomische Nachrichten / Astronomical Notes as a contribution to SDW202
The Report of the American Heart Association Task Force on Strategies to Increase Federal Research Funding
Questioning the rise of gelatinous zooplankton in the World's oceans
During the past several decades, high numbers of gelatinous zooplankton species have been reported in many estuarine and coastal ecosystems. Coupled with media-driven public perception, a paradigm has evolved in which the global ocean ecosystems are thought to be heading toward being dominated by ânuisanceâ jellyfish. We question this current paradigm by presenting a broad overview of gelatinous zooplankton in a historicalcontext to develop the hypothesis that population changes reflect the human-mediated alteration of global ocean ecosystems. To this end, we synthesize information related to the evolutionary context of contemporary gelatinous zooplankton blooms, the human frame of reference forchanges in gelatinous zooplankton populations, and whether sufficient data are available to have established the paradigm. We conclude that the current paradigm in which it is believed that there has been a global increase in gelatinous zooplankton is unsubstantiated, and we develop a strategy for addressing the critical questions about long-term, human-related changes in the sea as they relate to gelatinous zooplankton blooms
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