Browsing by Subject "chemistry"
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Item Achieving the Science Standards: A National Study of Inquiry-Based Instruction in High School Science(Center for Applied Research and Educational Improvement, 1999) Huffman, Douglas; Lawrenz, FrancesThe National Science Teachers Association's SS&C(Scope, Sequence & Coordination)project created a new high school science curriculum that coordinated the content in the four basic sciences (life, earth, physics and chemistry) to allow students to study every science every year. The curriculum sequenced activities to encourage teachers to use inquiry-based instruction where students engage in hands-on activities before teachers define concepts.To examine the impact of SS&C, researchers at CAREI designed a comprehensive study comparing students who took SS&C science in 9th and 10th grade to students who did not take the new course. The study used a time-lag design which compares the prior year's science students to the present year's science students. The purpose of the study was to closely examine the effect of the standards-based curriculum on both the classroom learning environment and on students' achievement in the sciences. Thirteen schools implemented the new science course. The schools were located in California, Iowa, Montana, New York, North Carolina, Texas and the District of Columbia and included more than 4,000 ninth graders and 2,500 tenth grade science students.Item Information Circular 2. Chemical Analyses of Igneous Rocks(Minnesota Geological Survey, 1965) Ruotsala, Albert P.; Tufford, Sarah P.The available chemical analyses of igneous rocks of Minnesota are compiled and grouped by rock type in the 10 tables that comprise this report. In each table, analyses appear in chronological order according to date of original publication. The sample locality, the analyst, and the original publication are listed for each analysis. Four of the 232 analyses are unpublished, and were obtained from the files of the Rock Analyses Laboratory of the University of Minnesota, now inactive. Most of the chemical analyses presented here were compiled originally by Ruotsala (unpublished M. S. thesis, University of Minnesota, 1955). All known new analyses have been added, and the tables are believed to include all analyses made before 1965. All totals were checked and corrected. A modal analysis is available for those samples marked by an asterisk.Item Information Circular 22. Analytical Results of the Public Geologic Sample Program, 1983-1985 Biennium(Minnesota Geological Survey, 1985) Morey, G.B.; McSwiggen, Peter L.; Kuhns, Mary Jo P.; Jirsa, Mark A.In 1983 the Minnesota Geological Survey, in conjunction with the Minnesota Department of Natural Resources, Division of Minerals, began a geologic sample program whereby the general public was encouraged to submit samples of geologic material for identification and possible analysis. The program was roughly patterned after a similar program in Finland. The Finnish program has resulted in a heightened public interest in the mineral potential of that country and has resulted in the discovery of several ore deposits. It was for those reasons, as well as the potential increase in geologic knowledge that could result, that a similar program was initiated in Minnesota. As originally conceived, the geologic sample program was to focus on samples submitted to the Minnesota Geological Survey by the general public. As part of its public service function, the Survey was to identify and classify rock or mineral samples that were collected in the state. If any of the samples were thought to have potential scientific or economic interest, they were to be submitted for chemical analyses or other appropriate tests. A copy of a brochure that was prepared to advertise the program is shown in Figure 1, and the sample submittal form that sets forth the operating conditions for the program is shown in Figure 2. The brochure and other publicity about the program led to requests for 238 submittal forms and to approximately 500 walk-in and telephone requests for additional information. Unfortunately, of the more than 700 inquiries, only 9 samples were ultimately judged suitable for additional chemical analysis (Table 1). The "suitability" rate of only slightly more than 1 percent was due to a number of factors. Many people only became aware of the program very late in the biennium. Other people who had samples of scientific or economic interest were unwilling to submit those samples to the Geological Survey for several reasons, including (a) the expense of mailing samples, (b) an unwillingness to part with a "prized" specimen, or (c) a lack of knowledge about mineral rights (i.e., a fear of jeopardizing their rights by revealing the location of a sample). However the great majority of samples were submitted by individuals who simply wanted them identified without concern as to possible scientific or economic value. Because of the sluggish public response, the program was modified in early 1985 to include samples of scientific or economic interest that were submitted by personnel of the Minnesota Department of Natural Resources, Division of Minerals, or the Minnesota Geological Survey. This programmatic change led to the additional analysis of 304 samples from various components of the Early Proterozoic Animikie basin on the Mesabi and Cuyuna ranges and in east-central Minnesota (Tables 2, 3, 4, and 7) and from various poorly known rock units in southwestern (Tables 5 and 8) and southeastern Minnesota (Tables 6 and 9).Item Information Circular 23. Scientific Core Drilling in Central Minnesota: Summary of Lithologic and Geochemical Results(Minnesota Geological Survey, 1986) Southwick, D.L.; Meyer, Gary N.; Mills, Sarah J.In 1980 the Minnesota Geological Survey (MGS) began a program of scientific test drilling for the purpose of acquiring a better understanding of the complex Precambrian bedrock of central Minnesota. The areas investigated in this project contain very few bedrock outcrops; the Precambrian rocks are thickly covered by unconsolidated surficial deposits of Quaternary age, and the only way they can be directly sampled and studied is by core drilling. This circular is an essentially uninterpreted summary of basic lithologic and chemical data derived from the scientific core drilling project.Item Information Circular 25. Analytical Results of the Public Geologic Sample Program, 1985-1987 Biennium(Minnesota Geological Survey, 1987) Morey, G.B.; McDonald, Linda L.In 1983 the Minnesota Geological Survey, in conjunction with the Minnesota Department of Natural Resources, Division of Minerals, began a geologic sample program involving the chemical analysis of geological materials, in part submitted by the general public. This Information Circular summarizes the results of that program during the 1985-1987 biennium. In all, 163 samples were analyzed for a variety of minor and trace elements (Tables 1-6); 111 samples were analyzed for major elements as well as minor and trace elements (Tables 7-12). The tables within those categories are organized by the geological age of the materials analyzed.Item Information Circular 28. Graphite in Early Proterozoic Rocks of East-Central Minnesota(Minnesota Geological Survey, 1989) McSwiggen, Peter L.; Morey, G.B.The Penokean orogen and southern Animikie basin of cast-central Minnesota contain numerous carbonaceous units. The carbon content of these units ranges from as little as 1-2 wt.% to as much as 44 wt.%; the thickness of these units ranges from a few inches to over 500 feet. By using published values for the energy content of some Finnish and Swedish carbonaceous rocks, it is possible to estimate the energy content in samples from this study. These values indicate that a ton of rock with 44 wt.% graphite contains approximately as much energy as one ton of lignite or a half ton of bituminous coal. This suggests that such a rock contains roughly $13.50-19.00/ton worth of energy. In certain localities, the carbonaceous units also contain significant precious and base metal concentrations. Values of as much as 350 ppb gold and 6 ppm silver were recorded.Item Information Circular 29. Analytical Results of the Public Geologic Sample Program, 1987-1989 Biennium(Minnesota Geological Survey, 1989) Morey, G.B.; McDonald, Linda L.In 1983 the Minnesota Geological Survey, in conjunction with the Minnesota Department of Natural Resources, Division of Minerals, began a geologic sample program involving the chemical analysis of geological materials, in part submitted by the general public. This Information Circular summarizes the results of that program during the 1987-1989 biennium. In all, 166 samples were evaluated by Survey geologists as potential candidates. Of that total, 129 samples were rejected because they were not deemed suitable for analysis and 25 samples were rejected because the submitters were unwilling or unable to provide locations as required by the program. In the end, 4 public samples (Tables 1, 4, and 9) were analyzed for a variety of constituents. Additionally, 326 samples submitted by Survey geologists were analyzed for a variety of major, minor, and trace constituents. The analytical results from 10 other miscellaneous samples were also donated to the Survey during the biennium and are included in this report. Tables within those categories are organized by the geological age of the material analyzed.Item Information Circular 38. Analytical Results of the Public Geologic Sample Program, 1989-1991 Biennium(Minnesota Geological Survey, 1992) Morey, G.B.; Day, L.S.In 1983 the Minnesota Geological Survey, in conjunction with the Minnesota Department of Natural Resources, Division of Minerals, began a geologic sample program involving the chemical analysis of geologic materials, in part submitted by the general public. This Information Circular summarizes the results of that program during the 1989-1991 biennium. In all, 106 samples were evaluated by Survey geologists as potential candidates. In addition we received 115 written and phone requests for information about the program. In the end, only one public sample (Table 1 and 7) was analyzed for a variety of constituents. Also, 308 samples of Archean to Quaternary age submitted by Survey geologists were analyzed for a variety of major, minor, and trace constituents. Tables within those categories are organized by the geologic age of the material analyzed. In addition, 39 samples of water derived from the Hinckley-Mt. Simon aquifer of southeastern Minnesota were analyzed for their trace-element contents (Table 13), as were 33 samples for the del S34 content (Table 14). Effective July 1.1989, the program was discontinued; this is the last report in this series.Item Information Circular 41. Geochemical Investigation of Minor and Trace Elements in the Acid-Insoluble Residues of Lower Paleozoic Carbonate and Related Strata, Southeastern Minnesota-The Data Base(Minnesota Geological Survey, 1994) Morey, G.B.; Lively, R.S.; Mossler, John H.; Hauck, S.A.The Upper Mississippi Valley mining district in Iowa, Wisconsin, and Illinois is one of several world-class lead-zinc mineral districts in developed Paleozoic strata of the northern Midcontinent. Although Mississippi Valley-type deposits vary considerably from district to district, they are defined as being predominantly sphalerite-galena replacement and vein deposits-including vug and breccia fillings-in carbonate host rocks. In general, they are restricted to certain formations; as such they are peneconformable but clearly crosscutting. Therefore, Mississippi Valley-type mineral deposits are epigenetic and stratabound, but not stratiform. Minor occurrences of base-metal sulfides also are present in calcareous and, to a lesser extent, in shaly and sandy rocks in a broad zone surrounding the main Upper Mississippi Valley lead-zinc district. These outlying occurrences are of special interest because similarities in form, distinctive mineral paragenesis, and sulfur and lead isotope systematics imply that they were cogenetic with mineralization in the main district. The outlying occurrences may represent remnants of fluid pathways associated with mineralization in the main district. To evaluate the extent of mineralization in southeastern Minnesota, we initiated a geochemical study that focused on the minor-and trace-element content of insoluble residues in carbonate rocks, using samples from drill holes and operating quarries throughout southeastern Minnesota (Fig. 2; Tables 4-52 in appendix). Regional geochemical studies of this kind have revealed, even in rocks that appear to be barren of sulfide ores, a suite of metals characteristic of Mississippi Valley-type mineral deposits. In particular, this suite includes Pb, Zn, As, Cu, Ni, Ca, Ag, and Mo. Geochemical analysis of insoluble residues from Paleozoic carbonate rocks has become an integral part of the assessment of mineral resources in the northern Midcontinent (Erickson and others, 1981, 1983; Mosier and Motooka, 1983; Viets and others, 1983). Insoluble residues are the materials remaining after calcium carbonate has been dissolved in a aqueous solution of 5:1 hydrochloric acid. Measurements of the minor-and trace- element composition of the residues provide a rapid, yet sensitive means of identifying regional ground-water flow patterns of metal-bearing brines. The method also appears to have some applicability in identifying previously unrecognized areas with Mississippi Valley-type lead- zinc deposits and, by extension, providing clues to possible locations of mineral deposits in southeastern Minnesota.Item Modeling the Active Sites of Copper Monooxygenase Enzymes(2017-07) Neisen, BenjaminMechanistic investigation of copper-oxygen intermediates relevant to the oxygenation reactions of copper monooxygenase enzymes is a long-standing goal of bioinorganic chemists. To elucidate and understand the key species in copper monooxygenase pathways, small molecule synthetic chemistry has been employed to discretely generate and characterize individual species of interest. In Chapter 1, previous enzymatic and modeling work with respect to copper monooxygenase chemistry is discussed and current mechanistic proposals are explored in detail. Chapter 2 describes modeling studies of monocopper sites and the influence of secondary sphere hydrogen bonding interactions on their redox behavior. A series of monocopper complexes with secondary sphere hydrogen bond interactions were determined to result in large increases of the electrochemical potentials of the CuIII/CuII redox couple when compared to non-hydrogen bound analogs. The hydrogen bonding model systems provide evidence for the structure-function relationship of secondary coordination influences on metal-containing active sites. Chapter 3 discusses development of a previously undescribed dinucleating macrocyclic ligand, designed to support dicopper-oxygen cores relevant to the enzyme particulate methane monooxygenase (pMMO). Attempts to generate dicopper-hydroxo type cores resulted in hydrolytic products found to be dicopper complexes that were crystallographically characterized. Observed “paddle wheel” type configurations with cis-labile coordination sites in the dicopper complexes represent a class of compounds with diverse coordination chemistry. The final chapter (Chapter 4) describes the synthesis and characterization of a formal CuIII-alkylperoxo core utilizing spectroscopic and computational methods. The CuIII-alkylperoxo complex has been shown to undergo proton-coupled electron-transfer (PCET) reactions with weak O-H bond substrates. The CuIII-alkylperoxo core is considered to be a model system of a CuIII-OOH core, proposed to be a possible reactive intermediate in lytic polysaccharide monooxygenase (LPMO).Item Spring Characterization Methods & Springshed Mapping(Proceedings of the 11th Multidisciplinary Conference on Sinkholes and the Engineering and Environmental Impacts of Karst. © 2008 American Society of Civil Engineers. Published online: June 20, 2012, 2008-09-26) Alexander, Scott C; Luhmann, Andrew J; Alexander Jr., E. Calvin; Green, Jeffrey A; Peters, Andrew JSoutheastern Minnesota's karst lands support numerous trout streams created by coldwater springs emanating from Paleozoic bedrock. While trout streams have been traditionally managed as surface water resources they are fundamentally supported by clear, relatively constant temperature groundwater. In karst areas this groundwater resource is as vulnerable as surface waters to human activities. Designing Best Management Practices (BMPs) to protect groundwater fed springs should improve the overall protection of Minnesota's trout streams. Dye tracing has been the tool of choice for mapping the recharge area or groundwater basin that feed a particular spring. These karst groundwater basins have been termed "springsheds". In order to accelerate springshed mapping, a two~year study was funded by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR). To improve the effectiveness of dye tracing we are applying a variety of new tools to increase our knowledge of the underlying karst systems. Techniques being investigated include temperature and discharge monitoring, detailed structural mapping of the aquifers, unit hydrographs, chemical and isotopic studies. These new methods to define the size and geometry of springsheds can be tested against basins previously defined by dye tracing. In previously untraced basins these predictive tools can be used to design more efficient tracing programs. The following paper demonstrates the application of structural mapping to dye tracing.