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In order to preserve groundwater as a viable source of drinking water, remedial measures must be applied where appropriate. The application of the various remedial technologies is site and contaminant dependent. Differing geology, subsurface soil, groundwater geochemistry, type of contaminant present, cost and even accessibility to the site are all considerations when selecting an appropriate remedial system. At many sites oxygen is a limiting factor for aerobic degradation of many organic compounds like methyl tert butyl ether (MTBE) and hydrocarbons found in diesel and fuel oil, etc. (Nyer et al, 2002). Mechanisms limiting the success of getting the oxygen out of the passive release well include: · Slow chemical diffusion of oxygen in water; · Limited cross section of the groundwater flowing into the well and advecting oxygenated water back into the aquifer; and · Generally weak transverse dispersion, both horizontal and vertical, during subsequent advection of the oxygenated water in the porous media. These issues must be recognized even in the design of a passive release well remediation system. For example, a typical remedial objective is to deliver dissolved oxygen across the width and vertical extent of a contaminant zone in an aquifer. The width of the oxygen plume around the injection well defines how many oxygen-release wells are required to create a curtain of oxygen. Cost-effective design dictates fewer wells, while effective coverage may dictate more wells placed closer together. Thus, understanding the transverse width over which significant oxygen is passively released to the aquifer (the “radius of influence”) is a critical design parameter and the focus of this thesis. Due to the difficulty in getting a passively released dissolved oxygen plume to transversely encompass the total width of a contaminant plume, other more efficient means of introducing oxygen into the subsurface are required. Injecting amended water directly into a release well would increase the transverse distance in which dissolved oxygen would spread. A series of experiments were conducted at CFB Borden to assess the efficacy of an oxygen releasing technology called the iSOC™. The experiments were all conducted in the same manner, by connecting a tank of oxygen to the iSOC™ unit, which then was placed in a release well and allowed to run in experiment 1 for 103 days, experiment 2 for 132 days and experiment 3 for 29 days. iv Dissolved oxygen concentrations were measured at varying time intervals throughout each experiment using an Orion dissolved oxygen probe. Results of each of the three experiments were very similar in that dissolved oxygen was only detected in a very narrow plume (10 cm to 25 cm in width) within 1 m of the release well. The presence of BTEX, BOD and COD within the groundwater and soil at the site were investigated to assess if presented a significant enough sink for the oxygen and thereby limiting the transverse growth of the dissolved oxygen plume. Groundwater results indicated that while dissolved oxygen was utilized for BTEX degradation and to overcome the natural oxygen demand (both BOD and COD) at the site, the amount of oxygen released into the aquifer would have satisfied both of these processes. The COD of the soil at the site presented a higher oxygen demand than the groundwater and presented a greater limiting factor to the transverse growth of the oxygen plume. By releasing oxygen passively with the iSOC™ only a small transverse portion of the Borden aquifer was likely influenced. This limitation has been noted in general for passive release technologies (Wilson & Mackay, 1995). While the iSOCÔ technology develops very high oxygen levels in the groundwater in the release well, it does not overcome the hydrogeological constraint of limited transverse dispersion. Thus, a high oxygen concentration is delivered to a very narrow segment of the aquifer. Overall, transverse dispersion has a minimal impact on a passively release oxygen plume, particularly in close proximity to the release well, but once the plume has migrated a distance away from the release well the effect of transverse dispersion increases. The oxygen demand of an aquifer can also limit the effect of transverse and longitudinal dispersion. If a site has a high chemical or biological oxygen demand the released gas will be consumed before dispersion can have an effect on the plume. By injecting nutrient rich water into a release well the water will forcibly overcome any influence transverse dispersion will have in and around a release well, thereby relying on longitudinal dispersion to create a larger area for contaminant degradation to occur.

In order to preserve groundwater as a viable source of drinking water, remedial measures must be applied where appropriate. The application of the various remedial technologies is site and contaminant dependent. Differing geology, subsurface soil, groundwater geochemistry, type of contaminant present, cost and even accessibility to the site are all considerations when selecting an appropriate remedial system. At many sites oxygen is a limiting factor for aerobic degradation of many organic compounds like methyl tert butyl ether (MTBE) and hydrocarbons found in diesel and fuel oil, etc. (Nyer et al, 2002). Mechanisms limiting the success of getting the oxygen out of the passive release well include: · Slow chemical diffusion of oxygen in water; · Limited cross section of the groundwater flowing into the well and advecting oxygenated water back into the aquifer; and · Generally weak transverse dispersion, both horizontal and vertical, during subsequent advection of the oxygenated water in the porous media. These issues must be recognized even in the design of a passive release well remediation system. For example, a typical remedial objective is to deliver dissolved oxygen across the width and vertical extent of a contaminant zone in an aquifer. The width of the oxygen plume around the injection well defines how many oxygen-release wells are required to create a curtain of oxygen. Cost-effective design dictates fewer wells, while effective coverage may dictate more wells placed closer together. Thus, understanding the transverse width over which significant oxygen is passively released to the aquifer (the “radius of influence”) is a critical design parameter and the focus of this thesis. Due to the difficulty in getting a passively released dissolved oxygen plume to transversely encompass the total width of a contaminant plume, other more efficient means of introducing oxygen into the subsurface are required. Injecting amended water directly into a release well would increase the transverse distance in which dissolved oxygen would spread. A series of experiments were conducted at CFB Borden to assess the efficacy of an oxygen releasing technology called the iSOC™. The experiments were all conducted in the same manner, by connecting a tank of oxygen to the iSOC™ unit, which then was placed in a release well and allowed to run in experiment 1 for 103 days, experiment 2 for 132 days and experiment 3 for 29 days. iv Dissolved oxygen concentrations were measured at varying time intervals throughout each experiment using an Orion dissolved oxygen probe. Results of each of the three experiments were very similar in that dissolved oxygen was only detected in a very narrow plume (10 cm to 25 cm in width) within 1 m of the release well. The presence of BTEX, BOD and COD within the groundwater and soil at the site were investigated to assess if presented a significant enough sink for the oxygen and thereby limiting the transverse growth of the dissolved oxygen plume. Groundwater results indicated that while dissolved oxygen was utilized for BTEX degradation and to overcome the natural oxygen demand (both BOD and COD) at the site, the amount of oxygen released into the aquifer would have satisfied both of these processes. The COD of the soil at the site presented a higher oxygen demand than the groundwater and presented a greater limiting factor to the transverse growth of the oxygen plume. By releasing oxygen passively with the iSOC™ only a small transverse portion of the Borden aquifer was likely influenced. This limitation has been noted in general for passive release technologies (Wilson & Mackay, 1995). While the iSOCÔ technology develops very high oxygen levels in the groundwater in the release well, it does not overcome the hydrogeological constraint of limited transverse dispersion. Thus, a high oxygen concentration is delivered to a very narrow segment of the aquifer. Overall, transverse dispersion has a minimal impact on a passively release oxygen plume, particularly in close proximity to the release well, but once the plume has migrated a distance away from the release well the effect of transverse dispersion increases. The oxygen demand of an aquifer can also limit the effect of transverse and longitudinal dispersion. If a site has a high chemical or biological oxygen demand the released gas will be consumed before dispersion can have an effect on the plume. By injecting nutrient rich water into a release well the water will forcibly overcome any influence transverse dispersion will have in and around a release well, thereby relying on longitudinal dispersion to create a larger area for contaminant degradation to occur.

Various methods, programs, and efforts to educate students in effective and efficient ways have been employed and studied for many years in the United States. Many teachers, administrators, and communities seek to gain a better understanding of and implement programs that will help achieve the academic goals of their respective organizations. Previous research indicates a correlation between some types of classes, programs, and characteristics of students and their academic achievement. Data indicating academic information for three hundred and fifty suburban secondary school students were collected and analyzed to support or refute previous research in this area of study. Grade point averages of these students were analyzed based on the characteristics of gender, age, core and non-core course selection, and enrollment in released-time religious education (RTRE) courses. Results indicated that selected characteristics of students were positively correlated with increased academic achievement. Such characteristics included: involvement in RTRE, the number of non-core courses taken, and the number of core courses taken. Students who were enrolled in fewer courses generally exhibited higher grade point averages. Results also indicated that the age and gender of students had little if any effect on their academic performance. (52 pages)

Throughout their lives, prey organisms must balance the tradeoff between fitness-related activities and the risk of predation. To successfully mediate such tradeoffs, prey must have an accurate method to gauge current predation risk. For many aquatic organisms, the use of chemosensory information has been shown to be a ubiquitous and useful tool in mediating predation risk. The chemical cues to which aquatic organisms respond include the odour of known predators and the odour of a damaged conspecific or known or closely related heterospecific. In fishes, the response to damage-released cues from conspecifics or closely related heterospecifics has been shown to be innate, while the response to distantly related unknown heterospecific cues are likely learned. In a series of laboratory and field studies I examined the role of learning in the ability of fathead minnows to respond to damage-released cues of brook stickleback as an indication of predation risk. My results indicate that minnows from a population without stickleback do not recognize stickleback cues as dangerous. However, following the introduction of stickleback, minnows learn to recognize stickleback cues as dangerous. Further study indicated a low ratio of stickleback to minnows in a given population will decrease the likelihood of learning when compared with a similar sized population containing a higher ratio of stickleback to minnows. I also demonstrated that an increase in habitat complexity decreases the ability of minnows to learn to recognize stickleback cues. Studies have further demonstrated that in the face of predation (as indicated by chemical cues from minnows and stickleback) minnows will decrease their antipredator response when in the presence of a fish shoal, especially a shoal of conspecifics. Finally, an examination of the effects of a minnows length, body condition and breeding status indicate that morphological parameters can play a significant role in the intensity of response to heterospecific and conspecific damage-released cues. Previous works have demonstrated that behavioural responses to heterospecific damage-released cues increase the probability of the receiver surviving a predation event. This has important implications for predator/prey interactions and consequently factors affecting the learning and use of such cues deserve increasing attention from ecologists.

Throughout their lives, prey organisms must balance the tradeoff between fitness-related activities and the risk of predation. To successfully mediate such tradeoffs, prey must have an accurate method to gauge current predation risk. For many aquatic organisms, the use of chemosensory information has been shown to be a ubiquitous and useful tool in mediating predation risk. The chemical cues to which aquatic organisms respond include the odour of known predators and the odour of a damaged conspecific or known or closely related heterospecific. In fishes, the response to damage-released cues from conspecifics or closely related heterospecifics has been shown to be innate, while the response to distantly related unknown heterospecific cues are likely learned. In a series of laboratory and field studies I examined the role of learning in the ability of fathead minnows to respond to damage-released cues of brook stickleback as an indication of predation risk. My results indicate that minnows from a population without stickleback do not recognize stickleback cues as dangerous. However, following the introduction of stickleback, minnows learn to recognize stickleback cues as dangerous. Further study indicated a low ratio of stickleback to minnows in a given population will decrease the likelihood of learning when compared with a similar sized population containing a higher ratio of stickleback to minnows. I also demonstrated that an increase in habitat complexity decreases the ability of minnows to learn to recognize stickleback cues. Studies have further demonstrated that in the face of predation (as indicated by chemical cues from minnows and stickleback) minnows will decrease their antipredator response when in the presence of a fish shoal, especially a shoal of conspecifics. Finally, an examination of the effects of a minnows length, body condition and breeding status indicate that morphological parameters can play a significant role in the intensity of response to heterospecific and conspecific damage-released cues. Previous works have demonstrated that behavioural responses to heterospecific damage-released cues increase the probability of the receiver surviving a predation event. This has important implications for predator/prey interactions and consequently factors affecting the learning and use of such cues deserve increasing attention from ecologists.

Contamination of soil/groundwater supplies by gasoline and other petroleum-derived hydrocarbons released from underground storage tanks (USTs) is a serious and widespread environmental problem. Corrosion, ground movement, and poor sealing can cause leaks in tanks and associated piping. Petroleum hydrocarbons contain methyl tertiary-butyl ether (MTBE) (a fuel oxygenate), benzene, toluene, ethylbenzene, and xylene isomers (BTEX), the major components of gasoline, which are hazardous substances regulated by many nations.The objective of this proposed study is to assess the potential of using a passive in situ oxidation barrier system. This passive active barrier system has advantages over conventional systems including less maintenance, cost-effectiveness, no above-ground facilities, no groundwater pumping and reinjection, and groundwater remediation in situ. The oxidation barrier system included a persulfate-releasing barrier, which contains persulfate-releasing materials. The slow-released persulfate would oxidize MTBE and benzene in aquifer. The persulfate-releasing materials would release persulfate when contacts with groundwater, thus oxidizes the MTBE and benzene. In the first part of this study, bench scale experiment was also performed to produce the persulfate-releasing materials high persulfate-releasing rate. The components of the persulfate-releasing materials and optimal concentrations of those components were determined in this study. Results indicate that the highest persulfate releasing rate can be obtained when the mass ratio of cement/sand/water was 1.4/0/0.7. Result obtained from the persulfate-releasing materials test and bench-scale were used for the design and operation of the following column experiments. Results from the column experiment indicate that approximately 98% of MTBE and 99% of benzene could be removed during the early persulfate-releasing stage. Results also reveal that the produced oxidation byproducts of MTBE, tert-butyl formate (TBF) and tert-butyl alcohol (TBA), can also be produce an acetone. Results from this study suggest that extra Fe(II) would cause the decrease in oxidation rates due to the reaction of sulfate with Fe(II). Results show that the parameters, which would affect the oxidation rate include persulfate concentration, oxidant reduction potential (ORP), conductivity, sulfate concentration, and contaminant concentration. The proposed treatment scheme would be expected to provide a more cost-effective alternative to remediate MTBE and other petroleum-hydrocarbon contaminated aquifers. Knowledge obtained from this study will aid in designing a persulfate oxidation system for site remediation.

The subject of this master thesis is a released share. The paper is divided into 2 main parts which correspond with 2 main goals of this thesis - a detailed analysis of general provisions on a released share and analysis of the collision of provisions governing the released share and a share pledge. In the general part of the thesis, the released share is described thoroughly, as well as the process of how the companies have to deal with it. The structure of the general part follows the structure of the Business Corporations Act. Firstly, the released share is described, followed by the sale of released share with all its problems, settlement share and the process the company follows after the settlement share is paid out, i.e. the transfer of the released share to the remaining members or reduction of registered capital. In the general part of the thesis I also compare the effective legislation and the amendment of Business Corporations Act which is being prepared at the time of writing this paper and which could bring solutions to many problems arising out of the effective legislation. In the special part, which I assume to be the key part of this paper, I analyse the collision of regulations of released share and share pledge. To begin with, I describe the rights of the pledgee to the released pledged...

<p>Urea has been widely used as a crop fertilizer to increase crop yield. The low nutrient use efficiency (NUE) of urea, however, is a challenge. Coated fertilizers are considered a solution not only for enhancing the NUE but also for alleviating soil and water pollution. In this paper, the physical properties of coated fertilizers were analyzed, including their particle size distribution, fracture force, thermal behavior, envelope density, and apparent density (regular fertilizer: pure urea and the Anderson 12-6-6; slow release fertilizer: Osmocote 14-14-14, the Anderson 18-6-12; controlled release fertilizer: Environmentally smart nitrogen (ESN), Florikan 14-14-14, Everris 17-3-6). The granules’ closed and open pore number, pore volume, and total porosity were analyzed using X-ray micro-tomography (XRCT). The results demonstrated that pure urea and Florikan have a similar median particle size, around 4 mm, while ESN and Osmocote have a similar median particle size of around 3 mm. Finally, Everris, the Andersons 18-6-12, and the Andersons 12-6-6, have a similar median particle size of roughly 2.5 mm. The fracture pressure of ESN (4.58±0.98 MPa) and the NPK combination fertilizers (Florikan: 9.40±1.46 MPa and Osmocote: 8.94±2.09 MPa) were higher than pure urea. The envelope and apparent density of pure urea (envelope: 1.22±0.02 kg/m³ and apparent: 1.27±0.01 kg/m³) and ESN (envelope: 1.26±0.03 kg/m³ and apparent: 1.27±0.00 kg/m³) are similar, while all NPK fertilizers have a significantly higher density (envelope: 1.68–1.87 kg/m³ and apparent: 1.83–2.09 kg/m³). ESN had higher internal pore space and a higher total pore volume than pure urea, while NPK combination fertilizer showed lesser pores and significantly smaller pore volumes. The physical properties were also significantly different when comparing urea and NPK compound fertilizers, mainly because of the differences in their nutrient coatings and manufacturing methods. The coating of the urea increases the granule strength but does not alter the thermal properties; however, the overall porosity of the granules is influenced by the coating. In this thesis core, different binders were used to alter the internal structure of the urea granule to control the dissolution behavior and to make it a slow-release fertilizer. The layered agglomeration technique was used to manufacture the granules. The core of the granule was made by granulating technical urea powder in a drum granulator, with corn starch as the binder. A second layer of urea was added to the core by drum granulation in order to obtain a nutrient release pattern that matches with the crop demand. Corn starch, PEG 4000, and corn starch hydrogel were used as binders for the second layer. The density, thermal properties, strength, and internal porosity were measured to compare with market urea and coated slow-release fertilizer granules. All the dissolution rates of the double layer granules were slower than for market urea. Among these granule types, the dissolution rate curve of the granule with starch hydrogel in the second layer better matched the crop demand curve than those of the other two types of granules. Moreover, the strength of the double layer granules with hydrogel was the greatest of the three double layer granules. So, overall, the double layer granule manufactured with corn starch in the core and starch hydrogel in the second layer performed the best. Although the pattern of dissolution of the double layer granule was similar to the crop nitrate demand curve, a soil-based study is needed to verify the nitrate release characteristics.<br></p><ul> </ul>

This qualitative study examined the relationship between Utah public high schools and Latter-day Saint (LDS) released-time seminaries through the perspectives and practices of principals from both institutions. The study followed methods consistent with phenomenological research. Data were analyzed through a theory of social exchange. Sites and participants were purposefully selected using a criterion phenomenal variation strategy. Sites included six Utah public high schools with LDS seminaries adjacent. Participants included the public school and seminary principals at those sites. The overarching question that guided the study was: How is the professional relationship between the public schools and LDS seminaries in Utah perceived and practiced by principals of both institutions? The three subquestions used to support the central question were: (1) What are principals’ perceptions of the relationship? (2) How is the relationship maintained? (3) Why is the relationship maintained? Findings from the study suggested that public school and seminary principals, for the most part, perceived the public school-LDS seminary relationship to be: (a) working well; (b) valuable and mutually beneficial; and (c) equitable. Findings further suggested that the relationships were maintained: (a) through reciprocal efforts to accommodate, support, and show appreciation for each other; (b) by following historically established norms; and (c) by being sensitive to legal parameters established for the relationship. Findings also suggested that the relationships were maintained because: (a) each institution has become dependent upon the other; (b) the relationship benefits both parties; (c) the benefits received outweigh any challenges that result from the relationship; (d) the relationship has become an expectation and ingrained part of the culture of the state; (e) positive emotions result from the relationship; and (f) the relationship is beneficial to the students.