726 research outputs found
Circular 16
Edda, an introduction from Sweden, was recommended
for the first tim e in 195 I for all barley-growing
areas of Alaska. About 200 bushels of this new barley
variety were available for distribution to Alaska growers
in 195 I through the Alaska Agricultural Experiment
Station. Because Edda is early, stiff-strawed, highyielding,
and of good quality it is expected to have an
im portant place in the production of feed and seed in
the Territory. A nalytical chemical determ inations
suggest that Edda is at least equal in feeding value to
similar varieties grown in Alaska and to Stateside barleys.In cooperation with the United States Department of Agriculture, Agricultural Research Administratio
A Microfluidic Method to Measure Diffusion in Hydrogels
A novel microfluidic method is proposed for studying diffusion of small molecules in a hydrogel. Microfluidic devices were prepared with semi-permeable microchannels defined by crosslinked poly(ethylene glycol) (PEG). Uptake of dye molecules from aqueous solutions flowing through the microchannels was observedoptically and diffusion of the dye into the hydrogel was quantified. To complement the diffusion measurements from the microfluidic studies, nuclear magnetic resonance(NMR) characterization of the diffusion of dye in the PEG hydrogels was performed. The diffusion of small molecules in a hydrogel is relevant to applications such asdrug delivery and modeling transport for tissue-engineering applications. The diffusion of small molecules in a hydrogel is dependent on the extent of crosslinking within the gel, gel structure, and interactions between the diffusive species and the hydrogel network. These effects were studied in a model environment (semi-infinite slab) at the hydrogelfluid boundary in a microfluidic device. The microfluidic devices containing PEG microchannels were fabricated using photolithography. The unsteady diffusion of small molecules (dyes) within the microfluidic device was monitored and recorded using a digital microscope. The information was analyzed with techniques drawn from digital microscopy and image analysis to obtain concentration profiles with time. Using a diffusion model to fit this concentration vs. position data, a diffusion coefficient was obtained. This diffusion coefficient was compared to those from complementary NMR analysis. A pulsed field gradient (PFG) method was used to investigate and quantify small molecule diffusion in gradient (PFG) method was used to investigate and quantify small molecule diffusion in hydrogels. There is good agreement between the diffusion coefficients obtained from the microfluidic methods and those found from the NMR studies. The microfluidic approachused in this research enables the study of diffusion at length scales that approach those of vasculature, facilitating models for studying drug elution from hydrogels in blood-contacting applications
Inheritance of resistance to specific races of crown and stem rust, to Helminthosporium blight, and of certain agronomic characters of oats
Observed segregation for reaction to stem rust in several oat crosses was on a monohybrid basis except in the cross Sac x Hajira-Joanette where segregation was observed to be on a three-factor basis. A mesothetic type of reaction to the composite of races 2 and 8 was observed in seedling plants classified as susceptible in two crosses, Mindo x Tama and Sac x Hajira-Joanette. Since no segregation was observed for reaction to race 2 in either of the two crosses, one factor pair for resistance to race 8 must be allelic to the one governing resistance to race 2 possessed by Tama and Hajira x Joanette.
Segregation for reaction to races 1 and 45 of crown rust was on a monogenic, digenic or trigenic basis in different crosses investigated. Five different factors for resistance to crown rust were identified in this study: A and B, complementary dominant factors which give the Bond type (type 0) of resistance of race 1; L, a simple dominant which gives the Landhafer type of resistance (type 0-1) to races 1 and 45; S, a simple dominant from Santa Fe which governs resistance (type 0) to races 1 and 45; and V, a simple dominant of the hypersensitive type (type 2) from Victoria which also governs resistance to races 1 and 45. The factor from Santa Fe (S) appears to be of great promise as a source of resistance to the relatively prevalent race 45. Many desirable agronomic progenies possessing resistance to races 1 and 45 from the cross of Santa Fe x Clinton have been selected for further testing. Very few selections have been made from Mindo x Landhafer for testing in F4. The L factor does not appear to be too satisfactory under the conditions of this experiment for resistance in the mature plant stage
Rheological study of kaolin clay slurries
Concentrated kaolin clay slurries are found in a number of industrial operations including mine tailings surface disposal, underground paste backfill, and riverbed dredging. An understanding of the impact of solids concentration and addition of chemical species on slurry rheology is of importance to designers of pipeline transport and waste disposal systems. A project to determine the rheology of an idealized industrial kaolin clay slurry using a concentric cylinder viscometer and an experimental pipeline loop was undertaken. Additional laboratory test work including particle size analysis, slurry pH, calcium ion concentration in the slurry supernatant and particle electrophoretic mobility measurements were completed to aid in the understanding of their effects on the slurry rheology.
The slurries were prepared in varying kaolin clay solids concentrations with reverse osmosis water. A flocculant, dihydrated calcium chloride (CaCl2 ¡¤ 2H2O), was added to the reverse osmosis water in concentrations equivalent to those found in typical industrial hard water supply. A dispersant, tetra-sodium pyrophosphate (TSPP, Na4P2O7) was used to disperse the clay particles for selected slurries.
It was found that the kaolin clay slurries, in the absence of TSPP, exhibited yield stresses and could be characterized with either the two-parameter Bingham or Casson continuum flow models. Increasing the clay concentration in the slurry, while keeping the mass ratio of flocculant to kaolin constant, increased both the yield and plastic viscosity parameters. There was generally good agreement between the rheological parameters obtained in the Couette flow viscometer and that in the pipeline loop.
In slurries for which it was possible to obtain turbulent flow, the transition to turbulent flow was predicted accurately by the Wilson & Thomas method for both Bingham and Casson models.
It was possible to eliminate the yield stress of a slurry with the addition of the dispersing agent TSPP. The calcium ion content of the supernatant extracted from the slurries proved to be a indicator of the degree of flocculation.
When exposed to extended periods of high shear conditions in the pipeline loop, slurries with clay concentrations of 17% by volume solids or greater exhibited an irreversible increase in apparent viscosity with time. An attempt was made to investigate this irreversible thickening characteristic. Laboratory tests did not reveal any appreciable differences in particle size, electrophoretic mobility, calcium ion concentration or pH with this irreversible change. The shear duration test shows the importance of using the appropriate shear environment when testing high solids concentration kaolin clay slurrie
Sexual Orientation and Family Development: Introduction
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72859/1/h0085089.pd
Impact of traffic management on black carbon emissions: a microsimulation study
This paper investigates the effectiveness of traffic management tools, includ- ing traffic signal control and en-route navigation provided by variable message signs (VMS), in reducing traffic congestion and associated emissions of CO2, NOx, and black carbon. The latter is among the most significant contributors of climate change, and is associated with many serious health problems. This study combines traffic microsimulation (S-Paramics) with emission modeling (AIRE) to simulate and predict the impacts of different traffic management measures on a number traffic and environmental Key Performance Indicators (KPIs) assessed at different spatial levels. Simulation results for a real road network located in West Glasgow suggest that these traffic management tools can bring a reduction in travel delay and BC emission respectively by up to 6 % and 3 % network wide. The improvement at local levels such as junctions or corridors can be more significant. However, our results also show that the potential benefits of such interventions are strongly dependent on a number of factors, including dynamic demand profile, VMS compliance rate, and fleet composition. Extensive discussion based on the simulation results as well as managerial insights are provided to support traffic network operation and control with environmental goals. The study described by this paper was conducted under the support of the FP7-funded CARBOTRAF project
Environmental impact of combined ITS traffic management strategies
Transport was responsible for 20% of the total greenhouse gas emissions in Europe during 2011 (European Environmental Agency 2013) with road transport being the key contributor. To tackle this, targets have been established in Europe and worldwide to curb transport emissions. This poses a significant challenge on Local Government and transport operators who need to identify a set of effective measures to reduce the environmental impact of road transport and at the same time keep the traffic smooth. Of the road transport pollutants, this paper considers NOx, CO2 and black carbon (BC). A particular focus is put on black carbon, which is formed through incomplete combustion of carboneous materials, as it has a significant impact on the Earth’s climate system. It absorbs solar radiation, influences cloud processes, and alters the melting of snow and ice cover (Bond et al. 2013). BC also causes serious health concerns: black carbon is associated with asthma and other respiratory problems, heart attacks and lung cancer (Sharma 2010; United States Environmental Protection Agency 2012). Since BC emissions are mainly produced during the decelerating and accelerating phases (Zhang et al. 2009), ITS actions able to reduce stop&go phases have the potential to reduce BC emissions. This paper investigates the effectiveness of combined ITS actions in urban context in reducing CO2 and BC emissions and improving traffic conditions
The role of episcopal theology and administration in the implementation of the settlement of religion, 1559-c. 1575
The term, Elizabethan Settlement, when applied solely to the adoption of the Prayer Book in 1559 or the Thirty-nine Articles in 1563, is misleading. The final form of the Settlement was the result of a creative struggle which involved Elizabeth and her advisers, together with the bishops and the local populace. The bishops introduced the Settlement in their dioceses and began a process of change which involved the laity and the local clergy. Through the ensuing implementation process the ultimate form of religion in England was defined
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