Design, fabrication and testing of subscale propellant tanks with capillary traps Final report, 26 Jun. 1967 - 15 Mar. 1968

Hyrostatic stability characteristics of perforated plates and square-weave screens for fluid control during low-G operatio

A new economical storage technique for strawberry (Fragaria × ananassa Duch.) in vitro

Strawberry plants grown in vitro are typically stored and maintained on agar containing Murashige and Skoog (MS) media and sucrose as a carbohydrate source. This method of storing strawberry plants in vitro is expensive and time consuming, requiring sub-culturing onto fresh media every 2 to 3 mo. This study aimed to establish the viability of using a substrate alternative as an economical replacement for MS media, for both long-term storage in vitro and ease of transfer (ex vitro). A protocol was developed for strawberry in vitro using commercially available sterilized peat pellets (Jiffy-7® pellets), to optimize culture conditions and tissue culture practices. Suitability of the peat substrate was measured by the plant’s overall response to culture in vitro and subsequent health and survival ex vitro following deflasking. Included in this study was a comparison of the use of vented vs non-vented tissue culture vessels for their effect on plant development and survival in vitro and ex vitro. The results show that strawberry plants can be grown and stored under in vitro conditions in vented vessels without sub-culturing for up to 3 yr or more. This equates to an approximately eightfold more efficient technique, significantly decreasing cost of storing and maintaining strawberry plants in vitro. Furthermore, plants grown in the peat substrate did not multiply, and had more established secondary roots than those grown in the conventional MS media

Developing knowledge and management of Strawberry Red Leaf Disorder

This research project conducted by the Department of Agriculture and Fisheries (DAF) and the University of Queensland (UQ), and co-funded through Hort Innovation, has led to the identification of potential causal agents of the strawberry Red Leaf Disorder (RLD). A better understanding of the spread and economic impact RLD has on the commercial Queensland (QLD) strawberry industry has resulted. RLD is characterised by reddish/maroon interveinal discolouration of the leaves and typically reduces plant vigour and yield. RLD is currently limiting the fruiting productivity and plant health of the major cultivars grown in QLD. Investigations into potential causes of RLD by DAF and UQ, have found no obvious single causal agent, suggesting that the disorder and mechanisms behind its transmission may be quite complex

An Examination of Middle School Students’ Attitudes Toward Science

For more than 40 years, researchers have been studying the persistent underrepresentation of women in science. Today, the gender gap has narrowed in some, but not all, disciplines of science. To better understand the impetus of this continuing problem, the attitudes of middle school students toward science were examined using a causal-comparative design based on biological sex across four attitude constructs: attitudes toward school science, desire to become a scientist, value of science to society, and perceptions of scientists. A sample of 450 sixth-, seventh-, and eighth-grade science students located in suburban, central New Jersey responded to Likert-type items on the My Attitudes Toward Science (MATS) survey during their regularly scheduled science class periods. Data analysis was performed through a multivariate analysis of variance. The findings indicated no statistically significant differences in middle school students’ attitudes toward school science, desire to become a scientist, value of science to society, and perceptions of scientists based on biological sex of the students. Implications for the findings are discussed

Moisture Meter Performance I. Corn Over Five Crop Years

The long-term accuracy of the 1981 Iowa-Illinois moisture-meter calibrations was evaluated by meter-to-oven comparisons on 2999 samples from the 1979-1983 crop years. Although the five-year average accuracy of the trade meters Steinlite SS250, Dickey-john GACII, and Motomco 919 was ±0.5 percentage point relative to the air-oven up to 25% moisture (wb), there was up to ± 0.7 point accuracy variation among crop years. A year-to-year component was added to the previously published variance model; this component represents about 35% of total variance of a meter test relative to an oven test

Experimental investigation of the effects of load path on the life of fretting fatigue contacts

Slip and changes to stresses within a load cycle both contribute to damage in fretting contacts. By considering conditions for slip in normal-bulk loaded fretting contacts, experiments were performed wherein the contact slip varied, whilst changes to stress were modest. This was achieved by keeping the load endpoints constant but altering the load path. Experiments showed stark contrast in life between tests permitting slip and those prohibiting it. FE models were used to plot slip and stress components, revealing that the differences in life were due to a combination of slip and changes in shear traction. A method is presented by which the crack position can be measured, by adding a feature to the pad to produce a datum mark

Regional Advisory Councils to Support Nascent Rural Entrepreneurs

Traditional economic development efforts have been unable to address the nuances of rural communities. Entrepreneurship can be an important process and a vital component for building rural resiliency. As part of RISE29, a grant funded program, regional advisory councils have been established an act as a crucial extension tool for East Carolina University. The goal of these councils is to incorporate the narrative and discourse of the importance of entrepreneurship as a part of inclusive rural economic development strategies

Storage Device Sizing for a Hybrid Railway Traction System by Means of Bicausal Bond Graphs

In this paper, the application of bicausal bond graphs for system design in electrical engineering is emphasized. In particular, it is shown how this approach is very useful for model inversion and parameter dimensioning. To illustrate these issues, a hybrid railway traction device is considered as a case study. The synthesis of a storage device (a supercapacitor) included in this system is then discussed

Superfluid Helium Tanker (SFHT) study

Replenishment of superfluid helium (SFHe) offers the potential of extending the on-orbit life of observatories, satellite instruments, sensors and laboratories which operate in the 2 K temperature regime. A reference set of resupply customers was identified as representing realistic helium servicing requirements and interfaces for the first 10 years of superfluid helium tanker (SFHT) operations. These included the Space Infrared Telescope Facility (SIRTF), the Advanced X-ray Astrophysics Facility (AXAF), the Particle Astrophysics Magnet Facility (Astromag), and the Microgravity and Materials Processing Sciences Facility (MMPS)/Critical Point Phenomena Facility (CPPF). A mixed-fleet approach to SFHT utilization was considered. The tanker permits servicing from the Shuttle cargo bay, in situ when attached to the OMV and carried to the user spacecraft, and as a depot at the Space Station. A SFHT Dewar ground servicing concept was developed which uses a dedicated ground cooling heat exchanger to convert all the liquid, after initial fill as normal fluid, to superfluid for launch. This concept permits the tanker to be filled to a near full condition, and then cooled without any loss of fluid. The final load condition can be saturated superfluid with any desired ullage volume, or the tank can be totally filed and pressurized. The SFHT Dewar and helium plumbing system design has sufficient component redundancy to meet fail-operational, fail-safe requirements, and is designed structurally to meet a 50 mission life usage requirement. Technology development recommendations were made for the selected SFHT concept, and a Program Plan and cost estimate prepared for a phase C/D program spanning 72 months from initiation through first launch in 1997