New Techniques for Thermo-electrochemical Analysis of Lithium-ion Batteries for Space Applications

The overall goal of this study was achieved: Replicated the numerical assessment performed by Chen et. al. (2005). Displayed the ability of Thermal Desktop to be coupled with thermo-electrochemical analysis techniques. such that the local heat generated on the cells is a function of the model itself using logic blocks and arrays. Differences in the TD temperature vs. depth of discharge profiles and Chen's was most likely due to differences in two primary areas: Contact regions and conductance values. Differences in density and specific heat values. center dot The model results are highly dependent on the accuracy of the material properties with respect to the multiple layers of an individual cell

Preliminary Investigation of the Occurrence and Distribution of Azotobacter on the Soils in Iowa

Berthelot in 1888 was the first to suggest that nitrogen may be added to field soils through the activity of microorganisms. In 1901 Beijerinck isolated a non-symbiotic, aerobic, nitrogen-fixing organism which he called Azotobacter chroococcum. Since this time five other species belonging to this genus have been isolated and likewise have been found capable of fixing atmospheric nitrogen

The occurrence of Azotobacter in Iowa soils and factors affecting their distribution

1. Two hundred eighty-seven Iowa soils representing 52 soil types and 37 soil series and distributed in the five soil areas of the state -the Wisconsin drift, the Iowan drift, the Missouri loess, the Southern Iowa loess and the Mississippi loess - were examined for the presence of Azotobacter. 2. The presence of the Azotobacter was determined in these soils by the Winogradsky soil plaque and the selective culture agar-plate methods using mannitol as the energy source. 3. Of the 287 samples collected, 101 or 35.2 percent contained Azotobacter. 4. The virgin, high-lime Knox soils of the Missouri loess soil area, the Webster soils of the Wisconsin drift soil area, the Clyde-Floyd soils of the Iowan drift soil area and the bottomland soils were generally positive with 100, 91.7, 71.4 and 76.4 per.cent, respectively, of the samples of these soils containing the bacteria. 5. The Clarion samples of the Wisconsin drift soil area and the terrace soils contained Azotobacter in only about one-third of the samples; the loessial soils, with the exception of the Knox, and the remaining drift samples only occasionally showed any growth of the organisms. 6. The samples were classified according to their topographic position which showed that the more depressed the position, the greater the percentage of samples which contained Azotobacter. 7. An analysis of the samples for pH, content of available phosphate, total nitrogen and calcium carbonate and a calculation of the ratio of carbonate to phosphate was made in order to determine whether or not any relation existed between the presence of the Azotobacter and anyone or all of these soil constituents. 8. A multiple correlation of the data arbitrarily summarized on the basis of pH showed that the presence of the Azotobacter in Iowa soils was closely associated with the pH and available phosphate content of the samples and associated very little with the total nitrogen content, the calcium carbonate content or the carbonate-phosphate ratio. The association with pH was closer than that with available phosphate. 9. A study of the limiting pH and available phosphate content values for Azotobacter in Iowa soils led to the conclusion that soils with pH values from about pH 5.42, the limiting value obtained by an extrapolation of the simple regression equation, to pH 6.0, below which only one sample contained the bacteria, and available phosphate contents less than 35 pounds per acre would probably not contain the bacteria. 10. A method recently developed by Fisher (12) was used to determine whether or not the pH, available phosphate content and total nitrogen content of the soils would serve to differentiate between the samples which contained Azotobacter and those which did not contain the organisms. It was found that these variables did significantly differentiate the two groups. The pH had the greatest influence in this respect, the available phosphate content the next greatest and the total nitrogen content had the least influence as a differentiating factor. These conclusions are in agreement with those obtained by the multiple correlation method. 11. The presence or absence of the Azotobacter in the principal soil series of Iowa may be largely explained on the basis of the characteristic pH and the content of available phosphate of the samples in each series. 12. In addition to the determination of factors which limited the occurrence of the Azotobacter in Iowa soils, a study was made of the factors which influenced the amount of growth which the Azotobacter would make in the soil. For this study only those samples were considered which contained the bacteria. 13. The available phosphate content of the samples which contained Azotobacter did not appear to be associated with the amount of Azotobacter growth. 14. The results for pH showed that an increase in the pH of the sample did improve conditions so that the Azotobacter could make a better growth. 15. The results for total nitrogen indicated that this variable exerted the greatest influence upon the amount of growth which the Azotobacter would make in the soil, when other factors were not unfavorable. 16. Some experimental plots were sampled to determine whether or not soils which did not originally contain the organisms could be treated with lime and rock phosphate to correct the acidity and deficiency in available phosphate and thus be put into condition to support a flora of Azotobacter. The results showed that the addition of lime to these soils had improved conditions so that the organisms were detected. Where rock phosphate was added in addition to the lime, a better growth of the organisms was not obtained. 17. A group of experimental plots on high-lime soils which contained large amounts of organic matter, as indicated by total nitrogen determinations, contained a vigorous growth of the Azotobacter as expected

Polymeric Bladder for Storing Liquid Oxygen

A proposed system for storing oxygen in liquid form and dispensing it in gaseous form is based on (1) initial subcooling of the liquid oxygen; (2) containing the liquid oxygen in a flexible vessel; (3) applying a gas spring to the flexible vessel to keep the oxygen compressed above the saturation pressure and, thus, in the liquid state; and (4) using heat leakage into the system for vaporizing the oxygen to be dispensed. In a typical prior system based on these principles, the flexible vessel is a metal bellows housed in a rigid tank, and the gas spring consists of pressurized helium in the tank volume surrounding the bellows. Unfortunately, the welds in the bellows corrugations are subject to fatigue, and, because bellows have large ullage, a correspondingly large fraction of the oxygen content cannot be expelled. In the proposed system, the flexible vessel would be a bladder made of a liquid- crystal polymer (LCP). (LCPs are strong and compatible with liquid oxygen.) In comparison with a metal bellows, a polymeric bladder would have less ullage and would weigh less. In experiments involving fatigue cycling at liquid-nitrogen temperatures, two LCPs were found to be suitable for this application

Blood immunoglobulins, complement and TNF receptor following minimally invasive surgery in patients undergoing pulmonary lobectomy

The reasons for improved survival following minimally invasive surgery remain elusive. Circulating mediators link surgical trauma, vascular and tissue homeostasis. Acute phase reactants, leukocytes and leukocyte Reactive Oxygen Species (ROS) are affected differentially by minimally invasive video-assisted thoracic surgery (VATS). Also, immunoglobulins, complement, TNF receptor and P-selectin changes have been observed, but the influence of minimally invasive surgery on these opsonins is less well defined. In this prospective randomised trial, 41 patients were randomly assigned to minimally invasive or open thoracic surgery, and immunoglobulins and vascular endothelial damage biomarkers were analysed. Humoral mediators (blood IgG, IgM, IgA; complement fragments C3, C4, and complement haemolytic index of activation CH50; TNF receptors I, II and P-selectin) were analysed before and 2, 5 and 7 days after surgery. Post-surgical changes in individual patients were determined. Substantial immunoglobulin decreases followed minimally invasive and open surgery. Decreased IgG, IgM and IgE were detected 2 days after surgery, and IgG and IgM after 7 days. These changes were greater than haemodilution, reaching greater significance in open surgery patients. Immunoglobulin decreases followed lymphocyte decreases. In contrast, increased complement and inflammatory endothelial cell signals (C3 and C4, soluble TNFR-II) were detected 7 days after surgery. In both groups, increased C3 and TNFR-II followed early acute phase reactants CRP, IL-6 and ROS. Acute phase reactants and CD4/CD8 lymphocytes were factors most attenuated in patients undergoing minimally invasive thoracic surgery (VATS). This study suggests local trauma mediators are better biomarkers than circulating opsonins in defining the response to minimally invasive surgery, and a systems approach, comparing individual metabolic responses, is effective in small patient groups

Frameworks to Develop Integrated STEM Curricula

Research-based frameworks can help K-12 schools develop integrated STEM curricula. Two frameworks are presented that describe the characteristics of effective integrated STEM lessons and effective engineering education. The second framework is a modification of the first. Modifications were made to align the framework to a school that was new to integrated STEM. The frameworks have promise for K-12 schools who wish to develop and implement an integrated STEM curriculum that may have different levels of experience and different types of support

Faculty Observables and Self-Reported Responsiveness to Academic Dishonesty

Prior to 2009, a mid-sized public institution in the southeast had a faculty-driven honor policy characterized by little education about the policy and no tracking of repeat offenders. An updated code, implemented in August of 2009, required that students sign an honor pledge, created a formal student honor board, and developed a process to track and hold accountable, repeat offenders. Self-reported data on faculty vigilance to detect and punish cheating is collected both prior to and after a change in the honor code at a mid-sized public institution in the southeast. We find that, at the time of the first survey, full professors and faculty with a longer duration of employment were more likely to claim vigilance in cheating detection and harshness in punishing cheaters than newer, untenured faculty. The relationship between these factors and detection and harshness diminished when the honor code was enhanced